1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 /* SPDX-License-Identifier: GPL-2.0 */ #ifndef _SCSI_SCSI_REQUEST_H #define _SCSI_SCSI_REQUEST_H #include <linux/blk-mq.h> #define BLK_MAX_CDB 16 struct scsi_request { unsigned char __cmd[BLK_MAX_CDB]; unsigned char *cmd; unsigned short cmd_len; int result; unsigned int sense_len; unsigned int resid_len; /* residual count */ int retries; void *sense; }; static inline struct scsi_request *scsi_req(struct request *rq) { return blk_mq_rq_to_pdu(rq); } static inline void scsi_req_free_cmd(struct scsi_request *req) { if (req->cmd != req->__cmd) kfree(req->cmd); } void scsi_req_init(struct scsi_request *req); #endif /* _SCSI_SCSI_REQUEST_H */
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ #ifndef _UAPI_LINUX_SWAB_H #define _UAPI_LINUX_SWAB_H #include <linux/types.h> #include <linux/compiler.h> #include <asm/bitsperlong.h> #include <asm/swab.h> /* * casts are necessary for constants, because we never know how for sure * how U/UL/ULL map to __u16, __u32, __u64. At least not in a portable way. */ #define ___constant_swab16(x) ((__u16)( \ (((__u16)(x) & (__u16)0x00ffU) << 8) | \ (((__u16)(x) & (__u16)0xff00U) >> 8))) #define ___constant_swab32(x) ((__u32)( \ (((__u32)(x) & (__u32)0x000000ffUL) << 24) | \ (((__u32)(x) & (__u32)0x0000ff00UL) << 8) | \ (((__u32)(x) & (__u32)0x00ff0000UL) >> 8) | \ (((__u32)(x) & (__u32)0xff000000UL) >> 24))) #define ___constant_swab64(x) ((__u64)( \ (((__u64)(x) & (__u64)0x00000000000000ffULL) << 56) | \ (((__u64)(x) & (__u64)0x000000000000ff00ULL) << 40) | \ (((__u64)(x) & (__u64)0x0000000000ff0000ULL) << 24) | \ (((__u64)(x) & (__u64)0x00000000ff000000ULL) << 8) | \ (((__u64)(x) & (__u64)0x000000ff00000000ULL) >> 8) | \ (((__u64)(x) & (__u64)0x0000ff0000000000ULL) >> 24) | \ (((__u64)(x) & (__u64)0x00ff000000000000ULL) >> 40) | \ (((__u64)(x) & (__u64)0xff00000000000000ULL) >> 56))) #define ___constant_swahw32(x) ((__u32)( \ (((__u32)(x) & (__u32)0x0000ffffUL) << 16) | \ (((__u32)(x) & (__u32)0xffff0000UL) >> 16))) #define ___constant_swahb32(x) ((__u32)( \ (((__u32)(x) & (__u32)0x00ff00ffUL) << 8) | \ (((__u32)(x) & (__u32)0xff00ff00UL) >> 8))) /* * Implement the following as inlines, but define the interface using * macros to allow constant folding when possible: * ___swab16, ___swab32, ___swab64, ___swahw32, ___swahb32 */ static inline __attribute_const__ __u16 __fswab16(__u16 val) { #if defined (__arch_swab16) return __arch_swab16(val); #else return ___constant_swab16(val); #endif } static inline __attribute_const__ __u32 __fswab32(__u32 val) { #if defined(__arch_swab32) return __arch_swab32(val); #else return ___constant_swab32(val); #endif } static inline __attribute_const__ __u64 __fswab64(__u64 val) { #if defined (__arch_swab64) return __arch_swab64(val); #elif defined(__SWAB_64_THRU_32__) __u32 h = val >> 32; __u32 l = val & ((1ULL << 32) - 1); return (((__u64)__fswab32(l)) << 32) | ((__u64)(__fswab32(h))); #else return ___constant_swab64(val); #endif } static inline __attribute_const__ __u32 __fswahw32(__u32 val) { #ifdef __arch_swahw32 return __arch_swahw32(val); #else return ___constant_swahw32(val); #endif } static inline __attribute_const__ __u32 __fswahb32(__u32 val) { #ifdef __arch_swahb32 return __arch_swahb32(val); #else return ___constant_swahb32(val); #endif } /** * __swab16 - return a byteswapped 16-bit value * @x: value to byteswap */ #ifdef __HAVE_BUILTIN_BSWAP16__ #define __swab16(x) (__u16)__builtin_bswap16((__u16)(x)) #else #define __swab16(x) \ (__builtin_constant_p((__u16)(x)) ? \ ___constant_swab16(x) : \ __fswab16(x)) #endif /** * __swab32 - return a byteswapped 32-bit value * @x: value to byteswap */ #ifdef __HAVE_BUILTIN_BSWAP32__ #define __swab32(x) (__u32)__builtin_bswap32((__u32)(x)) #else #define __swab32(x) \ (__builtin_constant_p((__u32)(x)) ? \ ___constant_swab32(x) : \ __fswab32(x)) #endif /** * __swab64 - return a byteswapped 64-bit value * @x: value to byteswap */ #ifdef __HAVE_BUILTIN_BSWAP64__ #define __swab64(x) (__u64)__builtin_bswap64((__u64)(x)) #else #define __swab64(x) \ (__builtin_constant_p((__u64)(x)) ? \ ___constant_swab64(x) : \ __fswab64(x)) #endif static __always_inline unsigned long __swab(const unsigned long y) { #if __BITS_PER_LONG == 64 return __swab64(y); #else /* __BITS_PER_LONG == 32 */ return __swab32(y); #endif } /** * __swahw32 - return a word-swapped 32-bit value * @x: value to wordswap * * __swahw32(0x12340000) is 0x00001234 */ #define __swahw32(x) \ (__builtin_constant_p((__u32)(x)) ? \ ___constant_swahw32(x) : \ __fswahw32(x)) /** * __swahb32 - return a high and low byte-swapped 32-bit value * @x: value to byteswap * * __swahb32(0x12345678) is 0x34127856 */ #define __swahb32(x) \ (__builtin_constant_p((__u32)(x)) ? \ ___constant_swahb32(x) : \ __fswahb32(x)) /** * __swab16p - return a byteswapped 16-bit value from a pointer * @p: pointer to a naturally-aligned 16-bit value */ static __always_inline __u16 __swab16p(const __u16 *p) { #ifdef __arch_swab16p return __arch_swab16p(p); #else return __swab16(*p); #endif } /** * __swab32p - return a byteswapped 32-bit value from a pointer * @p: pointer to a naturally-aligned 32-bit value */ static __always_inline __u32 __swab32p(const __u32 *p) { #ifdef __arch_swab32p return __arch_swab32p(p); #else return __swab32(*p); #endif } /** * __swab64p - return a byteswapped 64-bit value from a pointer * @p: pointer to a naturally-aligned 64-bit value */ static __always_inline __u64 __swab64p(const __u64 *p) { #ifdef __arch_swab64p return __arch_swab64p(p); #else return __swab64(*p); #endif } /** * __swahw32p - return a wordswapped 32-bit value from a pointer * @p: pointer to a naturally-aligned 32-bit value * * See __swahw32() for details of wordswapping. */ static inline __u32 __swahw32p(const __u32 *p) { #ifdef __arch_swahw32p return __arch_swahw32p(p); #else return __swahw32(*p); #endif } /** * __swahb32p - return a high and low byteswapped 32-bit value from a pointer * @p: pointer to a naturally-aligned 32-bit value * * See __swahb32() for details of high/low byteswapping. */ static inline __u32 __swahb32p(const __u32 *p) { #ifdef __arch_swahb32p return __arch_swahb32p(p); #else return __swahb32(*p); #endif } /** * __swab16s - byteswap a 16-bit value in-place * @p: pointer to a naturally-aligned 16-bit value */ static inline void __swab16s(__u16 *p) { #ifdef __arch_swab16s __arch_swab16s(p); #else *p = __swab16p(p); #endif } /** * __swab32s - byteswap a 32-bit value in-place * @p: pointer to a naturally-aligned 32-bit value */ static __always_inline void __swab32s(__u32 *p) { #ifdef __arch_swab32s __arch_swab32s(p); #else *p = __swab32p(p); #endif } /** * __swab64s - byteswap a 64-bit value in-place * @p: pointer to a naturally-aligned 64-bit value */ static __always_inline void __swab64s(__u64 *p) { #ifdef __arch_swab64s __arch_swab64s(p); #else *p = __swab64p(p); #endif } /** * __swahw32s - wordswap a 32-bit value in-place * @p: pointer to a naturally-aligned 32-bit value * * See __swahw32() for details of wordswapping */ static inline void __swahw32s(__u32 *p) { #ifdef __arch_swahw32s __arch_swahw32s(p); #else *p = __swahw32p(p); #endif } /** * __swahb32s - high and low byteswap a 32-bit value in-place * @p: pointer to a naturally-aligned 32-bit value * * See __swahb32() for details of high and low byte swapping */ static inline void __swahb32s(__u32 *p) { #ifdef __arch_swahb32s __arch_swahb32s(p); #else *p = __swahb32p(p); #endif } #endif /* _UAPI_LINUX_SWAB_H */
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 // SPDX-License-Identifier: GPL-2.0 /* * Helper routines for building identity mapping page tables. This is * included by both the compressed kernel and the regular kernel. */ static void ident_pmd_init(struct x86_mapping_info *info, pmd_t *pmd_page, unsigned long addr, unsigned long end) { addr &= PMD_MASK; for (; addr < end; addr += PMD_SIZE) { pmd_t *pmd = pmd_page + pmd_index(addr); if (pmd_present(*pmd)) continue; set_pmd(pmd, __pmd((addr - info->offset) | info->page_flag)); } } static int ident_pud_init(struct x86_mapping_info *info, pud_t *pud_page, unsigned long addr, unsigned long end) { unsigned long next; for (; addr < end; addr = next) { pud_t *pud = pud_page + pud_index(addr); pmd_t *pmd; next = (addr & PUD_MASK) + PUD_SIZE; if (next > end) next = end; if (info->direct_gbpages) { pud_t pudval; if (pud_present(*pud)) continue; addr &= PUD_MASK; pudval = __pud((addr - info->offset) | info->page_flag); set_pud(pud, pudval); continue; } if (pud_present(*pud)) { pmd = pmd_offset(pud, 0); ident_pmd_init(info, pmd, addr, next); continue; } pmd = (pmd_t *)info->alloc_pgt_page(info->context); if (!pmd) return -ENOMEM; ident_pmd_init(info, pmd, addr, next); set_pud(pud, __pud(__pa(pmd) | info->kernpg_flag)); } return 0; } static int ident_p4d_init(struct x86_mapping_info *info, p4d_t *p4d_page, unsigned long addr, unsigned long end) { unsigned long next; int result; for (; addr < end; addr = next) { p4d_t *p4d = p4d_page + p4d_index(addr); pud_t *pud; next = (addr & P4D_MASK) + P4D_SIZE; if (next > end) next = end; if (p4d_present(*p4d)) { pud = pud_offset(p4d, 0); result = ident_pud_init(info, pud, addr, next); if (result) return result; continue; } pud = (pud_t *)info->alloc_pgt_page(info->context); if (!pud) return -ENOMEM; result = ident_pud_init(info, pud, addr, next); if (result) return result; set_p4d(p4d, __p4d(__pa(pud) | info->kernpg_flag)); } return 0; } int kernel_ident_mapping_init(struct x86_mapping_info *info, pgd_t *pgd_page, unsigned long pstart, unsigned long pend) { unsigned long addr = pstart + info->offset; unsigned long end = pend + info->offset; unsigned long next; int result; /* Set the default pagetable flags if not supplied */ if (!info->kernpg_flag) info->kernpg_flag = _KERNPG_TABLE; /* Filter out unsupported __PAGE_KERNEL_* bits: */ info->kernpg_flag &= __default_kernel_pte_mask; for (; addr < end; addr = next) { pgd_t *pgd = pgd_page + pgd_index(addr); p4d_t *p4d; next = (addr & PGDIR_MASK) + PGDIR_SIZE; if (next > end) next = end; if (pgd_present(*pgd)) { p4d = p4d_offset(pgd, 0); result = ident_p4d_init(info, p4d, addr, next); if (result) return result; continue; } p4d = (p4d_t *)info->alloc_pgt_page(info->context); if (!p4d) return -ENOMEM; result = ident_p4d_init(info, p4d, addr, next); if (result) return result; if (pgtable_l5_enabled()) { set_pgd(pgd, __pgd(__pa(p4d) | info->kernpg_flag)); } else { /* * With p4d folded, pgd is equal to p4d. * The pgd entry has to point to the pud page table in this case. */ pud_t *pud = pud_offset(p4d, 0); set_pgd(pgd, __pgd(__pa(pud) | info->kernpg_flag)); } } return 0; }
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 /* SPDX-License-Identifier: GPL-2.0 */ #undef TRACE_SYSTEM #define TRACE_SYSTEM workqueue #if !defined(_TRACE_WORKQUEUE_H) || defined(TRACE_HEADER_MULTI_READ) #define _TRACE_WORKQUEUE_H #include <linux/tracepoint.h> #include <linux/workqueue.h> struct pool_workqueue; /** * workqueue_queue_work - called when a work gets queued * @req_cpu: the requested cpu * @pwq: pointer to struct pool_workqueue * @work: pointer to struct work_struct * * This event occurs when a work is queued immediately or once a * delayed work is actually queued on a workqueue (ie: once the delay * has been reached). */ TRACE_EVENT(workqueue_queue_work, TP_PROTO(unsigned int req_cpu, struct pool_workqueue *pwq, struct work_struct *work), TP_ARGS(req_cpu, pwq, work), TP_STRUCT__entry( __field( void *, work ) __field( void *, function) __field( void *, workqueue) __field( unsigned int, req_cpu ) __field( unsigned int, cpu ) ), TP_fast_assign( __entry->work = work; __entry->function = work->func; __entry->workqueue = pwq->wq; __entry->req_cpu = req_cpu; __entry->cpu = pwq->pool->cpu; ), TP_printk("work struct=%p function=%ps workqueue=%p req_cpu=%u cpu=%u", __entry->work, __entry->function, __entry->workqueue, __entry->req_cpu, __entry->cpu) ); /** * workqueue_activate_work - called when a work gets activated * @work: pointer to struct work_struct * * This event occurs when a queued work is put on the active queue, * which happens immediately after queueing unless @max_active limit * is reached. */ TRACE_EVENT(workqueue_activate_work, TP_PROTO(struct work_struct *work), TP_ARGS(work), TP_STRUCT__entry( __field( void *, work ) ), TP_fast_assign( __entry->work = work; ), TP_printk("work struct %p", __entry->work) ); /** * workqueue_execute_start - called immediately before the workqueue callback * @work: pointer to struct work_struct * * Allows to track workqueue execution. */ TRACE_EVENT(workqueue_execute_start, TP_PROTO(struct work_struct *work), TP_ARGS(work), TP_STRUCT__entry( __field( void *, work ) __field( void *, function) ), TP_fast_assign( __entry->work = work; __entry->function = work->func; ), TP_printk("work struct %p: function %ps", __entry->work, __entry->function) ); /** * workqueue_execute_end - called immediately after the workqueue callback * @work: pointer to struct work_struct * @function: pointer to worker function * * Allows to track workqueue execution. */ TRACE_EVENT(workqueue_execute_end, TP_PROTO(struct work_struct *work, work_func_t function), TP_ARGS(work, function), TP_STRUCT__entry( __field( void *, work ) __field( void *, function) ), TP_fast_assign( __entry->work = work; __entry->function = function; ), TP_printk("work struct %p: function %ps", __entry->work, __entry->function) ); #endif /* _TRACE_WORKQUEUE_H */ /* This part must be outside protection */ #include <trace/define_trace.h>
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 /* SPDX-License-Identifier: GPL-2.0 */ #undef TRACE_SYSTEM #define TRACE_SYSTEM tcp #if !defined(_TRACE_TCP_H) || defined(TRACE_HEADER_MULTI_READ) #define _TRACE_TCP_H #include <linux/ipv6.h> #include <linux/tcp.h> #include <linux/tracepoint.h> #include <net/ipv6.h> #include <net/tcp.h> #include <linux/sock_diag.h> #define TP_STORE_V4MAPPED(__entry, saddr, daddr) \ do { \ struct in6_addr *pin6; \ \ pin6 = (struct in6_addr *)__entry->saddr_v6; \ ipv6_addr_set_v4mapped(saddr, pin6); \ pin6 = (struct in6_addr *)__entry->daddr_v6; \ ipv6_addr_set_v4mapped(daddr, pin6); \ } while (0) #if IS_ENABLED(CONFIG_IPV6) #define TP_STORE_ADDRS(__entry, saddr, daddr, saddr6, daddr6) \ do { \ if (sk->sk_family == AF_INET6) { \ struct in6_addr *pin6; \ \ pin6 = (struct in6_addr *)__entry->saddr_v6; \ *pin6 = saddr6; \ pin6 = (struct in6_addr *)__entry->daddr_v6; \ *pin6 = daddr6; \ } else { \ TP_STORE_V4MAPPED(__entry, saddr, daddr); \ } \ } while (0) #else #define TP_STORE_ADDRS(__entry, saddr, daddr, saddr6, daddr6) \ TP_STORE_V4MAPPED(__entry, saddr, daddr) #endif /* * tcp event with arguments sk and skb * * Note: this class requires a valid sk pointer; while skb pointer could * be NULL. */ DECLARE_EVENT_CLASS(tcp_event_sk_skb, TP_PROTO(const struct sock *sk, const struct sk_buff *skb), TP_ARGS(sk, skb), TP_STRUCT__entry( __field(const void *, skbaddr) __field(const void *, skaddr) __field(int, state) __field(__u16, sport) __field(__u16, dport) __array(__u8, saddr, 4) __array(__u8, daddr, 4) __array(__u8, saddr_v6, 16) __array(__u8, daddr_v6, 16) ), TP_fast_assign( struct inet_sock *inet = inet_sk(sk); __be32 *p32; __entry->skbaddr = skb; __entry->skaddr = sk; __entry->state = sk->sk_state; __entry->sport = ntohs(inet->inet_sport); __entry->dport = ntohs(inet->inet_dport); p32 = (__be32 *) __entry->saddr; *p32 = inet->inet_saddr; p32 = (__be32 *) __entry->daddr; *p32 = inet->inet_daddr; TP_STORE_ADDRS(__entry, inet->inet_saddr, inet->inet_daddr, sk->sk_v6_rcv_saddr, sk->sk_v6_daddr); ), TP_printk("sport=%hu dport=%hu saddr=%pI4 daddr=%pI4 saddrv6=%pI6c daddrv6=%pI6c state=%s", __entry->sport, __entry->dport, __entry->saddr, __entry->daddr, __entry->saddr_v6, __entry->daddr_v6, show_tcp_state_name(__entry->state)) ); DEFINE_EVENT(tcp_event_sk_skb, tcp_retransmit_skb, TP_PROTO(const struct sock *sk, const struct sk_buff *skb), TP_ARGS(sk, skb) ); /* * skb of trace_tcp_send_reset is the skb that caused RST. In case of * active reset, skb should be NULL */ DEFINE_EVENT(tcp_event_sk_skb, tcp_send_reset, TP_PROTO(const struct sock *sk, const struct sk_buff *skb), TP_ARGS(sk, skb) ); /* * tcp event with arguments sk * * Note: this class requires a valid sk pointer. */ DECLARE_EVENT_CLASS(tcp_event_sk, TP_PROTO(struct sock *sk), TP_ARGS(sk), TP_STRUCT__entry( __field(const void *, skaddr) __field(__u16, sport) __field(__u16, dport) __array(__u8, saddr, 4) __array(__u8, daddr, 4) __array(__u8, saddr_v6, 16) __array(__u8, daddr_v6, 16) __field(__u64, sock_cookie) ), TP_fast_assign( struct inet_sock *inet = inet_sk(sk); __be32 *p32; __entry->skaddr = sk; __entry->sport = ntohs(inet->inet_sport); __entry->dport = ntohs(inet->inet_dport); p32 = (__be32 *) __entry->saddr; *p32 = inet->inet_saddr; p32 = (__be32 *) __entry->daddr; *p32 = inet->inet_daddr; TP_STORE_ADDRS(__entry, inet->inet_saddr, inet->inet_daddr, sk->sk_v6_rcv_saddr, sk->sk_v6_daddr); __entry->sock_cookie = sock_gen_cookie(sk); ), TP_printk("sport=%hu dport=%hu saddr=%pI4 daddr=%pI4 saddrv6=%pI6c daddrv6=%pI6c sock_cookie=%llx", __entry->sport, __entry->dport, __entry->saddr, __entry->daddr, __entry->saddr_v6, __entry->daddr_v6, __entry->sock_cookie) ); DEFINE_EVENT(tcp_event_sk, tcp_receive_reset, TP_PROTO(struct sock *sk), TP_ARGS(sk) ); DEFINE_EVENT(tcp_event_sk, tcp_destroy_sock, TP_PROTO(struct sock *sk), TP_ARGS(sk) ); DEFINE_EVENT(tcp_event_sk, tcp_rcv_space_adjust, TP_PROTO(struct sock *sk), TP_ARGS(sk) ); TRACE_EVENT(tcp_retransmit_synack, TP_PROTO(const struct sock *sk, const struct request_sock *req), TP_ARGS(sk, req), TP_STRUCT__entry( __field(const void *, skaddr) __field(const void *, req) __field(__u16, sport) __field(__u16, dport) __array(__u8, saddr, 4) __array(__u8, daddr, 4) __array(__u8, saddr_v6, 16) __array(__u8, daddr_v6, 16) ), TP_fast_assign( struct inet_request_sock *ireq = inet_rsk(req); __be32 *p32; __entry->skaddr = sk; __entry->req = req; __entry->sport = ireq->ir_num; __entry->dport = ntohs(ireq->ir_rmt_port); p32 = (__be32 *) __entry->saddr; *p32 = ireq->ir_loc_addr; p32 = (__be32 *) __entry->daddr; *p32 = ireq->ir_rmt_addr; TP_STORE_ADDRS(__entry, ireq->ir_loc_addr, ireq->ir_rmt_addr, ireq->ir_v6_loc_addr, ireq->ir_v6_rmt_addr); ), TP_printk("sport=%hu dport=%hu saddr=%pI4 daddr=%pI4 saddrv6=%pI6c daddrv6=%pI6c", __entry->sport, __entry->dport, __entry->saddr, __entry->daddr, __entry->saddr_v6, __entry->daddr_v6) ); #include <trace/events/net_probe_common.h> TRACE_EVENT(tcp_probe, TP_PROTO(struct sock *sk, struct sk_buff *skb), TP_ARGS(sk, skb), TP_STRUCT__entry( /* sockaddr_in6 is always bigger than sockaddr_in */ __array(__u8, saddr, sizeof(struct sockaddr_in6)) __array(__u8, daddr, sizeof(struct sockaddr_in6)) __field(__u16, sport) __field(__u16, dport) __field(__u32, mark) __field(__u16, data_len) __field(__u32, snd_nxt) __field(__u32, snd_una) __field(__u32, snd_cwnd) __field(__u32, ssthresh) __field(__u32, snd_wnd) __field(__u32, srtt) __field(__u32, rcv_wnd) __field(__u64, sock_cookie) ), TP_fast_assign( const struct tcphdr *th = (const struct tcphdr *)skb->data; const struct inet_sock *inet = inet_sk(sk); const struct tcp_sock *tp = tcp_sk(sk); memset(__entry->saddr, 0, sizeof(struct sockaddr_in6)); memset(__entry->daddr, 0, sizeof(struct sockaddr_in6)); TP_STORE_ADDR_PORTS(__entry, inet, sk); /* For filtering use */ __entry->sport = ntohs(inet->inet_sport); __entry->dport = ntohs(inet->inet_dport); __entry->mark = skb->mark; __entry->data_len = skb->len - __tcp_hdrlen(th); __entry->snd_nxt = tp->snd_nxt; __entry->snd_una = tp->snd_una; __entry->snd_cwnd = tp->snd_cwnd; __entry->snd_wnd = tp->snd_wnd; __entry->rcv_wnd = tp->rcv_wnd; __entry->ssthresh = tcp_current_ssthresh(sk); __entry->srtt = tp->srtt_us >> 3; __entry->sock_cookie = sock_gen_cookie(sk); ), TP_printk("src=%pISpc dest=%pISpc mark=%#x data_len=%d snd_nxt=%#x snd_una=%#x snd_cwnd=%u ssthresh=%u snd_wnd=%u srtt=%u rcv_wnd=%u sock_cookie=%llx", __entry->saddr, __entry->daddr, __entry->mark, __entry->data_len, __entry->snd_nxt, __entry->snd_una, __entry->snd_cwnd, __entry->ssthresh, __entry->snd_wnd, __entry->srtt, __entry->rcv_wnd, __entry->sock_cookie) ); #endif /* _TRACE_TCP_H */ /* This part must be outside protection */ #include <trace/define_trace.h>
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 // SPDX-License-Identifier: GPL-2.0 /* * Common header file for probe-based Dynamic events. * * This code was copied from kernel/trace/trace_kprobe.h written by * Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> * * Updates to make this generic: * Copyright (C) IBM Corporation, 2010-2011 * Author: Srikar Dronamraju */ #include <linux/seq_file.h> #include <linux/slab.h> #include <linux/smp.h> #include <linux/tracefs.h> #include <linux/types.h> #include <linux/string.h> #include <linux/ptrace.h> #include <linux/perf_event.h> #include <linux/kprobes.h> #include <linux/stringify.h> #include <linux/limits.h> #include <linux/uaccess.h> #include <linux/bitops.h> #include <asm/bitsperlong.h> #include "trace.h" #include "trace_output.h" #define MAX_TRACE_ARGS 128 #define MAX_ARGSTR_LEN 63 #define MAX_ARRAY_LEN 64 #define MAX_ARG_NAME_LEN 32 #define MAX_STRING_SIZE PATH_MAX /* Reserved field names */ #define FIELD_STRING_IP "__probe_ip" #define FIELD_STRING_RETIP "__probe_ret_ip" #define FIELD_STRING_FUNC "__probe_func" #undef DEFINE_FIELD #define DEFINE_FIELD(type, item, name, is_signed) \ do { \ ret = trace_define_field(event_call, #type, name, \ offsetof(typeof(field), item), \ sizeof(field.item), is_signed, \ FILTER_OTHER); \ if (ret) \ return ret; \ } while (0) /* Flags for trace_probe */ #define TP_FLAG_TRACE 1 #define TP_FLAG_PROFILE 2 /* data_loc: data location, compatible with u32 */ #define make_data_loc(len, offs) \ (((u32)(len) << 16) | ((u32)(offs) & 0xffff)) #define get_loc_len(dl) ((u32)(dl) >> 16) #define get_loc_offs(dl) ((u32)(dl) & 0xffff) static nokprobe_inline void *get_loc_data(u32 *dl, void *ent) { return (u8 *)ent + get_loc_offs(*dl); } static nokprobe_inline u32 update_data_loc(u32 loc, int consumed) { u32 maxlen = get_loc_len(loc); u32 offset = get_loc_offs(loc); return make_data_loc(maxlen - consumed, offset + consumed); } /* Printing function type */ typedef int (*print_type_func_t)(struct trace_seq *, void *, void *); enum fetch_op { FETCH_OP_NOP = 0, // Stage 1 (load) ops FETCH_OP_REG, /* Register : .param = offset */ FETCH_OP_STACK, /* Stack : .param = index */ FETCH_OP_STACKP, /* Stack pointer */ FETCH_OP_RETVAL, /* Return value */ FETCH_OP_IMM, /* Immediate : .immediate */ FETCH_OP_COMM, /* Current comm */ FETCH_OP_ARG, /* Function argument : .param */ FETCH_OP_FOFFS, /* File offset: .immediate */ FETCH_OP_DATA, /* Allocated data: .data */ // Stage 2 (dereference) op FETCH_OP_DEREF, /* Dereference: .offset */ FETCH_OP_UDEREF, /* User-space Dereference: .offset */ // Stage 3 (store) ops FETCH_OP_ST_RAW, /* Raw: .size */ FETCH_OP_ST_MEM, /* Mem: .offset, .size */ FETCH_OP_ST_UMEM, /* Mem: .offset, .size */ FETCH_OP_ST_STRING, /* String: .offset, .size */ FETCH_OP_ST_USTRING, /* User String: .offset, .size */ // Stage 4 (modify) op FETCH_OP_MOD_BF, /* Bitfield: .basesize, .lshift, .rshift */ // Stage 5 (loop) op FETCH_OP_LP_ARRAY, /* Array: .param = loop count */ FETCH_OP_END, FETCH_NOP_SYMBOL, /* Unresolved Symbol holder */ }; struct fetch_insn { enum fetch_op op; union { unsigned int param; struct { unsigned int size; int offset; }; struct { unsigned char basesize; unsigned char lshift; unsigned char rshift; }; unsigned long immediate; void *data; }; }; /* fetch + deref*N + store + mod + end <= 16, this allows N=12, enough */ #define FETCH_INSN_MAX 16 #define FETCH_TOKEN_COMM (-ECOMM) /* Fetch type information table */ struct fetch_type { const char *name; /* Name of type */ size_t size; /* Byte size of type */ int is_signed; /* Signed flag */ print_type_func_t print; /* Print functions */ const char *fmt; /* Fromat string */ const char *fmttype; /* Name in format file */ }; /* For defining macros, define string/string_size types */ typedef u32 string; typedef u32 string_size; #define PRINT_TYPE_FUNC_NAME(type) print_type_##type #define PRINT_TYPE_FMT_NAME(type) print_type_format_##type /* Printing in basic type function template */ #define DECLARE_BASIC_PRINT_TYPE_FUNC(type) \ int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s, void *data, void *ent);\ extern const char PRINT_TYPE_FMT_NAME(type)[] DECLARE_BASIC_PRINT_TYPE_FUNC(u8); DECLARE_BASIC_PRINT_TYPE_FUNC(u16); DECLARE_BASIC_PRINT_TYPE_FUNC(u32); DECLARE_BASIC_PRINT_TYPE_FUNC(u64); DECLARE_BASIC_PRINT_TYPE_FUNC(s8); DECLARE_BASIC_PRINT_TYPE_FUNC(s16); DECLARE_BASIC_PRINT_TYPE_FUNC(s32); DECLARE_BASIC_PRINT_TYPE_FUNC(s64); DECLARE_BASIC_PRINT_TYPE_FUNC(x8); DECLARE_BASIC_PRINT_TYPE_FUNC(x16); DECLARE_BASIC_PRINT_TYPE_FUNC(x32); DECLARE_BASIC_PRINT_TYPE_FUNC(x64); DECLARE_BASIC_PRINT_TYPE_FUNC(string); DECLARE_BASIC_PRINT_TYPE_FUNC(symbol); /* Default (unsigned long) fetch type */ #define __DEFAULT_FETCH_TYPE(t) x##t #define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t) #define DEFAULT_FETCH_TYPE _DEFAULT_FETCH_TYPE(BITS_PER_LONG) #define DEFAULT_FETCH_TYPE_STR __stringify(DEFAULT_FETCH_TYPE) #define __ADDR_FETCH_TYPE(t) u##t #define _ADDR_FETCH_TYPE(t) __ADDR_FETCH_TYPE(t) #define ADDR_FETCH_TYPE _ADDR_FETCH_TYPE(BITS_PER_LONG) #define __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \ {.name = _name, \ .size = _size, \ .is_signed = sign, \ .print = PRINT_TYPE_FUNC_NAME(ptype), \ .fmt = PRINT_TYPE_FMT_NAME(ptype), \ .fmttype = _fmttype, \ } #define _ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \ __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, #_fmttype) #define ASSIGN_FETCH_TYPE(ptype, ftype, sign) \ _ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, ptype) /* If ptype is an alias of atype, use this macro (show atype in format) */ #define ASSIGN_FETCH_TYPE_ALIAS(ptype, atype, ftype, sign) \ _ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, atype) #define ASSIGN_FETCH_TYPE_END {} #define MAX_ARRAY_LEN 64 #ifdef CONFIG_KPROBE_EVENTS bool trace_kprobe_on_func_entry(struct trace_event_call *call); bool trace_kprobe_error_injectable(struct trace_event_call *call); #else static inline bool trace_kprobe_on_func_entry(struct trace_event_call *call) { return false; } static inline bool trace_kprobe_error_injectable(struct trace_event_call *call) { return false; } #endif /* CONFIG_KPROBE_EVENTS */ struct probe_arg { struct fetch_insn *code; bool dynamic;/* Dynamic array (string) is used */ unsigned int offset; /* Offset from argument entry */ unsigned int count; /* Array count */ const char *name; /* Name of this argument */ const char *comm; /* Command of this argument */ char *fmt; /* Format string if needed */ const struct fetch_type *type; /* Type of this argument */ }; struct trace_uprobe_filter { rwlock_t rwlock; int nr_systemwide; struct list_head perf_events; }; /* Event call and class holder */ struct trace_probe_event { unsigned int flags; /* For TP_FLAG_* */ struct trace_event_class class; struct trace_event_call call; struct list_head files; struct list_head probes; struct trace_uprobe_filter filter[]; }; struct trace_probe { struct list_head list; struct trace_probe_event *event; ssize_t size; /* trace entry size */ unsigned int nr_args; struct probe_arg args[]; }; struct event_file_link { struct trace_event_file *file; struct list_head list; }; static inline bool trace_probe_test_flag(struct trace_probe *tp, unsigned int flag) { return !!(tp->event->flags & flag); } static inline void trace_probe_set_flag(struct trace_probe *tp, unsigned int flag) { tp->event->flags |= flag; } static inline void trace_probe_clear_flag(struct trace_probe *tp, unsigned int flag) { tp->event->flags &= ~flag; } static inline bool trace_probe_is_enabled(struct trace_probe *tp) { return trace_probe_test_flag(tp, TP_FLAG_TRACE | TP_FLAG_PROFILE); } static inline const char *trace_probe_name(struct trace_probe *tp) { return trace_event_name(&tp->event->call); } static inline const char *trace_probe_group_name(struct trace_probe *tp) { return tp->event->call.class->system; } static inline struct trace_event_call * trace_probe_event_call(struct trace_probe *tp) { return &tp->event->call; } static inline struct trace_probe_event * trace_probe_event_from_call(struct trace_event_call *event_call) { return container_of(event_call, struct trace_probe_event, call); } static inline struct trace_probe * trace_probe_primary_from_call(struct trace_event_call *call) { struct trace_probe_event *tpe = trace_probe_event_from_call(call); return list_first_entry(&tpe->probes, struct trace_probe, list); } static inline struct list_head *trace_probe_probe_list(struct trace_probe *tp) { return &tp->event->probes; } static inline bool trace_probe_has_sibling(struct trace_probe *tp) { struct list_head *list = trace_probe_probe_list(tp); return !list_empty(list) && !list_is_singular(list); } static inline int trace_probe_unregister_event_call(struct trace_probe *tp) { /* tp->event is unregistered in trace_remove_event_call() */ return trace_remove_event_call(&tp->event->call); } static inline bool trace_probe_has_single_file(struct trace_probe *tp) { return !!list_is_singular(&tp->event->files); } int trace_probe_init(struct trace_probe *tp, const char *event, const char *group, bool alloc_filter); void trace_probe_cleanup(struct trace_probe *tp); int trace_probe_append(struct trace_probe *tp, struct trace_probe *to); void trace_probe_unlink(struct trace_probe *tp); int trace_probe_register_event_call(struct trace_probe *tp); int trace_probe_add_file(struct trace_probe *tp, struct trace_event_file *file); int trace_probe_remove_file(struct trace_probe *tp, struct trace_event_file *file); struct event_file_link *trace_probe_get_file_link(struct trace_probe *tp, struct trace_event_file *file); int trace_probe_compare_arg_type(struct trace_probe *a, struct trace_probe *b); bool trace_probe_match_command_args(struct trace_probe *tp, int argc, const char **argv); #define trace_probe_for_each_link(pos, tp) \ list_for_each_entry(pos, &(tp)->event->files, list) #define trace_probe_for_each_link_rcu(pos, tp) \ list_for_each_entry_rcu(pos, &(tp)->event->files, list) #define TPARG_FL_RETURN BIT(0) #define TPARG_FL_KERNEL BIT(1) #define TPARG_FL_FENTRY BIT(2) #define TPARG_FL_MASK GENMASK(2, 0) extern int traceprobe_parse_probe_arg(struct trace_probe *tp, int i, char *arg, unsigned int flags); extern int traceprobe_update_arg(struct probe_arg *arg); extern void traceprobe_free_probe_arg(struct probe_arg *arg); extern int traceprobe_split_symbol_offset(char *symbol, long *offset); int traceprobe_parse_event_name(const char **pevent, const char **pgroup, char *buf, int offset); extern int traceprobe_set_print_fmt(struct trace_probe *tp, bool is_return); #ifdef CONFIG_PERF_EVENTS extern struct trace_event_call * create_local_trace_kprobe(char *func, void *addr, unsigned long offs, bool is_return); extern void destroy_local_trace_kprobe(struct trace_event_call *event_call); extern struct trace_event_call * create_local_trace_uprobe(char *name, unsigned long offs, unsigned long ref_ctr_offset, bool is_return); extern void destroy_local_trace_uprobe(struct trace_event_call *event_call); #endif extern int traceprobe_define_arg_fields(struct trace_event_call *event_call, size_t offset, struct trace_probe *tp); #undef ERRORS #define ERRORS \ C(FILE_NOT_FOUND, "Failed to find the given file"), \ C(NO_REGULAR_FILE, "Not a regular file"), \ C(BAD_REFCNT, "Invalid reference counter offset"), \ C(REFCNT_OPEN_BRACE, "Reference counter brace is not closed"), \ C(BAD_REFCNT_SUFFIX, "Reference counter has wrong suffix"), \ C(BAD_UPROBE_OFFS, "Invalid uprobe offset"), \ C(MAXACT_NO_KPROBE, "Maxactive is not for kprobe"), \ C(BAD_MAXACT, "Invalid maxactive number"), \ C(MAXACT_TOO_BIG, "Maxactive is too big"), \ C(BAD_PROBE_ADDR, "Invalid probed address or symbol"), \ C(BAD_RETPROBE, "Retprobe address must be an function entry"), \ C(BAD_ADDR_SUFFIX, "Invalid probed address suffix"), \ C(NO_GROUP_NAME, "Group name is not specified"), \ C(GROUP_TOO_LONG, "Group name is too long"), \ C(BAD_GROUP_NAME, "Group name must follow the same rules as C identifiers"), \ C(NO_EVENT_NAME, "Event name is not specified"), \ C(EVENT_TOO_LONG, "Event name is too long"), \ C(BAD_EVENT_NAME, "Event name must follow the same rules as C identifiers"), \ C(EVENT_EXIST, "Given group/event name is already used by another event"), \ C(RETVAL_ON_PROBE, "$retval is not available on probe"), \ C(BAD_STACK_NUM, "Invalid stack number"), \ C(BAD_ARG_NUM, "Invalid argument number"), \ C(BAD_VAR, "Invalid $-valiable specified"), \ C(BAD_REG_NAME, "Invalid register name"), \ C(BAD_MEM_ADDR, "Invalid memory address"), \ C(BAD_IMM, "Invalid immediate value"), \ C(IMMSTR_NO_CLOSE, "String is not closed with '\"'"), \ C(FILE_ON_KPROBE, "File offset is not available with kprobe"), \ C(BAD_FILE_OFFS, "Invalid file offset value"), \ C(SYM_ON_UPROBE, "Symbol is not available with uprobe"), \ C(TOO_MANY_OPS, "Dereference is too much nested"), \ C(DEREF_NEED_BRACE, "Dereference needs a brace"), \ C(BAD_DEREF_OFFS, "Invalid dereference offset"), \ C(DEREF_OPEN_BRACE, "Dereference brace is not closed"), \ C(COMM_CANT_DEREF, "$comm can not be dereferenced"), \ C(BAD_FETCH_ARG, "Invalid fetch argument"), \ C(ARRAY_NO_CLOSE, "Array is not closed"), \ C(BAD_ARRAY_SUFFIX, "Array has wrong suffix"), \ C(BAD_ARRAY_NUM, "Invalid array size"), \ C(ARRAY_TOO_BIG, "Array number is too big"), \ C(BAD_TYPE, "Unknown type is specified"), \ C(BAD_STRING, "String accepts only memory argument"), \ C(BAD_BITFIELD, "Invalid bitfield"), \ C(ARG_NAME_TOO_LONG, "Argument name is too long"), \ C(NO_ARG_NAME, "Argument name is not specified"), \ C(BAD_ARG_NAME, "Argument name must follow the same rules as C identifiers"), \ C(USED_ARG_NAME, "This argument name is already used"), \ C(ARG_TOO_LONG, "Argument expression is too long"), \ C(NO_ARG_BODY, "No argument expression"), \ C(BAD_INSN_BNDRY, "Probe point is not an instruction boundary"),\ C(FAIL_REG_PROBE, "Failed to register probe event"),\ C(DIFF_PROBE_TYPE, "Probe type is different from existing probe"),\ C(DIFF_ARG_TYPE, "Argument type or name is different from existing probe"),\ C(SAME_PROBE, "There is already the exact same probe event"), #undef C #define C(a, b) TP_ERR_##a /* Define TP_ERR_ */ enum { ERRORS }; /* Error text is defined in trace_probe.c */ struct trace_probe_log { const char *subsystem; const char **argv; int argc; int index; }; void trace_probe_log_init(const char *subsystem, int argc, const char **argv); void trace_probe_log_set_index(int index); void trace_probe_log_clear(void); void __trace_probe_log_err(int offset, int err); #define trace_probe_log_err(offs, err) \ __trace_probe_log_err(offs, TP_ERR_##err)
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User should soft dirty the page in the end callback to make * sure that anyone relying on soft dirtyness catch pages that might be written * through non CPU mappings. * * @MMU_NOTIFY_RELEASE: used during mmu_interval_notifier invalidate to signal * that the mm refcount is zero and the range is no longer accessible. * * @MMU_NOTIFY_MIGRATE: used during migrate_vma_collect() invalidate to signal * a device driver to possibly ignore the invalidation if the * migrate_pgmap_owner field matches the driver's device private pgmap owner. */ enum mmu_notifier_event { MMU_NOTIFY_UNMAP = 0, MMU_NOTIFY_CLEAR, MMU_NOTIFY_PROTECTION_VMA, MMU_NOTIFY_PROTECTION_PAGE, MMU_NOTIFY_SOFT_DIRTY, MMU_NOTIFY_RELEASE, MMU_NOTIFY_MIGRATE, }; #define MMU_NOTIFIER_RANGE_BLOCKABLE (1 << 0) struct mmu_notifier_ops { /* * Called either by mmu_notifier_unregister or when the mm is * being destroyed by exit_mmap, always before all pages are * freed. This can run concurrently with other mmu notifier * methods (the ones invoked outside the mm context) and it * should tear down all secondary mmu mappings and freeze the * secondary mmu. If this method isn't implemented you've to * be sure that nothing could possibly write to the pages * through the secondary mmu by the time the last thread with * tsk->mm == mm exits. * * As side note: the pages freed after ->release returns could * be immediately reallocated by the gart at an alias physical * address with a different cache model, so if ->release isn't * implemented because all _software_ driven memory accesses * through the secondary mmu are terminated by the time the * last thread of this mm quits, you've also to be sure that * speculative _hardware_ operations can't allocate dirty * cachelines in the cpu that could not be snooped and made * coherent with the other read and write operations happening * through the gart alias address, so leading to memory * corruption. */ void (*release)(struct mmu_notifier *subscription, struct mm_struct *mm); /* * clear_flush_young is called after the VM is * test-and-clearing the young/accessed bitflag in the * pte. This way the VM will provide proper aging to the * accesses to the page through the secondary MMUs and not * only to the ones through the Linux pte. * Start-end is necessary in case the secondary MMU is mapping the page * at a smaller granularity than the primary MMU. */ int (*clear_flush_young)(struct mmu_notifier *subscription, struct mm_struct *mm, unsigned long start, unsigned long end); /* * clear_young is a lightweight version of clear_flush_young. Like the * latter, it is supposed to test-and-clear the young/accessed bitflag * in the secondary pte, but it may omit flushing the secondary tlb. */ int (*clear_young)(struct mmu_notifier *subscription, struct mm_struct *mm, unsigned long start, unsigned long end); /* * test_young is called to check the young/accessed bitflag in * the secondary pte. This is used to know if the page is * frequently used without actually clearing the flag or tearing * down the secondary mapping on the page. */ int (*test_young)(struct mmu_notifier *subscription, struct mm_struct *mm, unsigned long address); /* * change_pte is called in cases that pte mapping to page is changed: * for example, when ksm remaps pte to point to a new shared page. */ void (*change_pte)(struct mmu_notifier *subscription, struct mm_struct *mm, unsigned long address, pte_t pte); /* * invalidate_range_start() and invalidate_range_end() must be * paired and are called only when the mmap_lock and/or the * locks protecting the reverse maps are held. If the subsystem * can't guarantee that no additional references are taken to * the pages in the range, it has to implement the * invalidate_range() notifier to remove any references taken * after invalidate_range_start(). * * Invalidation of multiple concurrent ranges may be * optionally permitted by the driver. Either way the * establishment of sptes is forbidden in the range passed to * invalidate_range_begin/end for the whole duration of the * invalidate_range_begin/end critical section. * * invalidate_range_start() is called when all pages in the * range are still mapped and have at least a refcount of one. * * invalidate_range_end() is called when all pages in the * range have been unmapped and the pages have been freed by * the VM. * * The VM will remove the page table entries and potentially * the page between invalidate_range_start() and * invalidate_range_end(). If the page must not be freed * because of pending I/O or other circumstances then the * invalidate_range_start() callback (or the initial mapping * by the driver) must make sure that the refcount is kept * elevated. * * If the driver increases the refcount when the pages are * initially mapped into an address space then either * invalidate_range_start() or invalidate_range_end() may * decrease the refcount. If the refcount is decreased on * invalidate_range_start() then the VM can free pages as page * table entries are removed. If the refcount is only * droppped on invalidate_range_end() then the driver itself * will drop the last refcount but it must take care to flush * any secondary tlb before doing the final free on the * page. Pages will no longer be referenced by the linux * address space but may still be referenced by sptes until * the last refcount is dropped. * * If blockable argument is set to false then the callback cannot * sleep and has to return with -EAGAIN if sleeping would be required. * 0 should be returned otherwise. Please note that notifiers that can * fail invalidate_range_start are not allowed to implement * invalidate_range_end, as there is no mechanism for informing the * notifier that its start failed. */ int (*invalidate_range_start)(struct mmu_notifier *subscription, const struct mmu_notifier_range *range); void (*invalidate_range_end)(struct mmu_notifier *subscription, const struct mmu_notifier_range *range); /* * invalidate_range() is either called between * invalidate_range_start() and invalidate_range_end() when the * VM has to free pages that where unmapped, but before the * pages are actually freed, or outside of _start()/_end() when * a (remote) TLB is necessary. * * If invalidate_range() is used to manage a non-CPU TLB with * shared page-tables, it not necessary to implement the * invalidate_range_start()/end() notifiers, as * invalidate_range() alread catches the points in time when an * external TLB range needs to be flushed. For more in depth * discussion on this see Documentation/vm/mmu_notifier.rst * * Note that this function might be called with just a sub-range * of what was passed to invalidate_range_start()/end(), if * called between those functions. */ void (*invalidate_range)(struct mmu_notifier *subscription, struct mm_struct *mm, unsigned long start, unsigned long end); /* * These callbacks are used with the get/put interface to manage the * lifetime of the mmu_notifier memory. alloc_notifier() returns a new * notifier for use with the mm. * * free_notifier() is only called after the mmu_notifier has been * fully put, calls to any ops callback are prevented and no ops * callbacks are currently running. It is called from a SRCU callback * and cannot sleep. */ struct mmu_notifier *(*alloc_notifier)(struct mm_struct *mm); void (*free_notifier)(struct mmu_notifier *subscription); }; /* * The notifier chains are protected by mmap_lock and/or the reverse map * semaphores. Notifier chains are only changed when all reverse maps and * the mmap_lock locks are taken. * * Therefore notifier chains can only be traversed when either * * 1. mmap_lock is held. * 2. One of the reverse map locks is held (i_mmap_rwsem or anon_vma->rwsem). * 3. No other concurrent thread can access the list (release) */ struct mmu_notifier { struct hlist_node hlist; const struct mmu_notifier_ops *ops; struct mm_struct *mm; struct rcu_head rcu; unsigned int users; }; /** * struct mmu_interval_notifier_ops * @invalidate: Upon return the caller must stop using any SPTEs within this * range. This function can sleep. Return false only if sleeping * was required but mmu_notifier_range_blockable(range) is false. */ struct mmu_interval_notifier_ops { bool (*invalidate)(struct mmu_interval_notifier *interval_sub, const struct mmu_notifier_range *range, unsigned long cur_seq); }; struct mmu_interval_notifier { struct interval_tree_node interval_tree; const struct mmu_interval_notifier_ops *ops; struct mm_struct *mm; struct hlist_node deferred_item; unsigned long invalidate_seq; }; #ifdef CONFIG_MMU_NOTIFIER #ifdef CONFIG_LOCKDEP extern struct lockdep_map __mmu_notifier_invalidate_range_start_map; #endif struct mmu_notifier_range { struct vm_area_struct *vma; struct mm_struct *mm; unsigned long start; unsigned long end; unsigned flags; enum mmu_notifier_event event; void *migrate_pgmap_owner; }; static inline int mm_has_notifiers(struct mm_struct *mm) { return unlikely(mm->notifier_subscriptions); } struct mmu_notifier *mmu_notifier_get_locked(const struct mmu_notifier_ops *ops, struct mm_struct *mm); static inline struct mmu_notifier * mmu_notifier_get(const struct mmu_notifier_ops *ops, struct mm_struct *mm) { struct mmu_notifier *ret; mmap_write_lock(mm); ret = mmu_notifier_get_locked(ops, mm); mmap_write_unlock(mm); return ret; } void mmu_notifier_put(struct mmu_notifier *subscription); void mmu_notifier_synchronize(void); extern int mmu_notifier_register(struct mmu_notifier *subscription, struct mm_struct *mm); extern int __mmu_notifier_register(struct mmu_notifier *subscription, struct mm_struct *mm); extern void mmu_notifier_unregister(struct mmu_notifier *subscription, struct mm_struct *mm); unsigned long mmu_interval_read_begin(struct mmu_interval_notifier *interval_sub); int mmu_interval_notifier_insert(struct mmu_interval_notifier *interval_sub, struct mm_struct *mm, unsigned long start, unsigned long length, const struct mmu_interval_notifier_ops *ops); int mmu_interval_notifier_insert_locked( struct mmu_interval_notifier *interval_sub, struct mm_struct *mm, unsigned long start, unsigned long length, const struct mmu_interval_notifier_ops *ops); void mmu_interval_notifier_remove(struct mmu_interval_notifier *interval_sub); /** * mmu_interval_set_seq - Save the invalidation sequence * @interval_sub - The subscription passed to invalidate * @cur_seq - The cur_seq passed to the invalidate() callback * * This must be called unconditionally from the invalidate callback of a * struct mmu_interval_notifier_ops under the same lock that is used to call * mmu_interval_read_retry(). It updates the sequence number for later use by * mmu_interval_read_retry(). The provided cur_seq will always be odd. * * If the caller does not call mmu_interval_read_begin() or * mmu_interval_read_retry() then this call is not required. */ static inline void mmu_interval_set_seq(struct mmu_interval_notifier *interval_sub, unsigned long cur_seq) { WRITE_ONCE(interval_sub->invalidate_seq, cur_seq); } /** * mmu_interval_read_retry - End a read side critical section against a VA range * interval_sub: The subscription * seq: The return of the paired mmu_interval_read_begin() * * This MUST be called under a user provided lock that is also held * unconditionally by op->invalidate() when it calls mmu_interval_set_seq(). * * Each call should be paired with a single mmu_interval_read_begin() and * should be used to conclude the read side. * * Returns true if an invalidation collided with this critical section, and * the caller should retry. */ static inline bool mmu_interval_read_retry(struct mmu_interval_notifier *interval_sub, unsigned long seq) { return interval_sub->invalidate_seq != seq; } /** * mmu_interval_check_retry - Test if a collision has occurred * interval_sub: The subscription * seq: The return of the matching mmu_interval_read_begin() * * This can be used in the critical section between mmu_interval_read_begin() * and mmu_interval_read_retry(). A return of true indicates an invalidation * has collided with this critical region and a future * mmu_interval_read_retry() will return true. * * False is not reliable and only suggests a collision may not have * occured. It can be called many times and does not have to hold the user * provided lock. * * This call can be used as part of loops and other expensive operations to * expedite a retry. */ static inline bool mmu_interval_check_retry(struct mmu_interval_notifier *interval_sub, unsigned long seq) { /* Pairs with the WRITE_ONCE in mmu_interval_set_seq() */ return READ_ONCE(interval_sub->invalidate_seq) != seq; } extern void __mmu_notifier_subscriptions_destroy(struct mm_struct *mm); extern void __mmu_notifier_release(struct mm_struct *mm); extern int __mmu_notifier_clear_flush_young(struct mm_struct *mm, unsigned long start, unsigned long end); extern int __mmu_notifier_clear_young(struct mm_struct *mm, unsigned long start, unsigned long end); extern int __mmu_notifier_test_young(struct mm_struct *mm, unsigned long address); extern void __mmu_notifier_change_pte(struct mm_struct *mm, unsigned long address, pte_t pte); extern int __mmu_notifier_invalidate_range_start(struct mmu_notifier_range *r); extern void __mmu_notifier_invalidate_range_end(struct mmu_notifier_range *r, bool only_end); extern void __mmu_notifier_invalidate_range(struct mm_struct *mm, unsigned long start, unsigned long end); extern bool mmu_notifier_range_update_to_read_only(const struct mmu_notifier_range *range); static inline bool mmu_notifier_range_blockable(const struct mmu_notifier_range *range) { return (range->flags & MMU_NOTIFIER_RANGE_BLOCKABLE); } static inline void mmu_notifier_release(struct mm_struct *mm) { if (mm_has_notifiers(mm)) __mmu_notifier_release(mm); } static inline int mmu_notifier_clear_flush_young(struct mm_struct *mm, unsigned long start, unsigned long end) { if (mm_has_notifiers(mm)) return __mmu_notifier_clear_flush_young(mm, start, end); return 0; } static inline int mmu_notifier_clear_young(struct mm_struct *mm, unsigned long start, unsigned long end) { if (mm_has_notifiers(mm)) return __mmu_notifier_clear_young(mm, start, end); return 0; } static inline int mmu_notifier_test_young(struct mm_struct *mm, unsigned long address) { if (mm_has_notifiers(mm)) return __mmu_notifier_test_young(mm, address); return 0; } static inline void mmu_notifier_change_pte(struct mm_struct *mm, unsigned long address, pte_t pte) { if (mm_has_notifiers(mm)) __mmu_notifier_change_pte(mm, address, pte); } static inline void mmu_notifier_invalidate_range_start(struct mmu_notifier_range *range) { might_sleep(); lock_map_acquire(&__mmu_notifier_invalidate_range_start_map); if (mm_has_notifiers(range->mm)) { range->flags |= MMU_NOTIFIER_RANGE_BLOCKABLE; __mmu_notifier_invalidate_range_start(range); } lock_map_release(&__mmu_notifier_invalidate_range_start_map); } static inline int mmu_notifier_invalidate_range_start_nonblock(struct mmu_notifier_range *range) { int ret = 0; lock_map_acquire(&__mmu_notifier_invalidate_range_start_map); if (mm_has_notifiers(range->mm)) { range->flags &= ~MMU_NOTIFIER_RANGE_BLOCKABLE; ret = __mmu_notifier_invalidate_range_start(range); } lock_map_release(&__mmu_notifier_invalidate_range_start_map); return ret; } static inline void mmu_notifier_invalidate_range_end(struct mmu_notifier_range *range) { if (mmu_notifier_range_blockable(range)) might_sleep(); if (mm_has_notifiers(range->mm)) __mmu_notifier_invalidate_range_end(range, false); } static inline void mmu_notifier_invalidate_range_only_end(struct mmu_notifier_range *range) { if (mm_has_notifiers(range->mm)) __mmu_notifier_invalidate_range_end(range, true); } static inline void mmu_notifier_invalidate_range(struct mm_struct *mm, unsigned long start, unsigned long end) { if (mm_has_notifiers(mm)) __mmu_notifier_invalidate_range(mm, start, end); } static inline void mmu_notifier_subscriptions_init(struct mm_struct *mm) { mm->notifier_subscriptions = NULL; } static inline void mmu_notifier_subscriptions_destroy(struct mm_struct *mm) { if (mm_has_notifiers(mm)) __mmu_notifier_subscriptions_destroy(mm); } static inline void mmu_notifier_range_init(struct mmu_notifier_range *range, enum mmu_notifier_event event, unsigned flags, struct vm_area_struct *vma, struct mm_struct *mm, unsigned long start, unsigned long end) { range->vma = vma; range->event = event; range->mm = mm; range->start = start; range->end = end; range->flags = flags; } static inline void mmu_notifier_range_init_migrate( struct mmu_notifier_range *range, unsigned int flags, struct vm_area_struct *vma, struct mm_struct *mm, unsigned long start, unsigned long end, void *pgmap) { mmu_notifier_range_init(range, MMU_NOTIFY_MIGRATE, flags, vma, mm, start, end); range->migrate_pgmap_owner = pgmap; } #define ptep_clear_flush_young_notify(__vma, __address, __ptep) \ ({ \ int __young; \ struct vm_area_struct *___vma = __vma; \ unsigned long ___address = __address; \ __young = ptep_clear_flush_young(___vma, ___address, __ptep); \ __young |= mmu_notifier_clear_flush_young(___vma->vm_mm, \ ___address, \ ___address + \ PAGE_SIZE); \ __young; \ }) #define pmdp_clear_flush_young_notify(__vma, __address, __pmdp) \ ({ \ int __young; \ struct vm_area_struct *___vma = __vma; \ unsigned long ___address = __address; \ __young = pmdp_clear_flush_young(___vma, ___address, __pmdp); \ __young |= mmu_notifier_clear_flush_young(___vma->vm_mm, \ ___address, \ ___address + \ PMD_SIZE); \ __young; \ }) #define ptep_clear_young_notify(__vma, __address, __ptep) \ ({ \ int __young; \ struct vm_area_struct *___vma = __vma; \ unsigned long ___address = __address; \ __young = ptep_test_and_clear_young(___vma, ___address, __ptep);\ __young |= mmu_notifier_clear_young(___vma->vm_mm, ___address, \ ___address + PAGE_SIZE); \ __young; \ }) #define pmdp_clear_young_notify(__vma, __address, __pmdp) \ ({ \ int __young; \ struct vm_area_struct *___vma = __vma; \ unsigned long ___address = __address; \ __young = pmdp_test_and_clear_young(___vma, ___address, __pmdp);\ __young |= mmu_notifier_clear_young(___vma->vm_mm, ___address, \ ___address + PMD_SIZE); \ __young; \ }) #define ptep_clear_flush_notify(__vma, __address, __ptep) \ ({ \ unsigned long ___addr = __address & PAGE_MASK; \ struct mm_struct *___mm = (__vma)->vm_mm; \ pte_t ___pte; \ \ ___pte = ptep_clear_flush(__vma, __address, __ptep); \ mmu_notifier_invalidate_range(___mm, ___addr, \ ___addr + PAGE_SIZE); \ \ ___pte; \ }) #define pmdp_huge_clear_flush_notify(__vma, __haddr, __pmd) \ ({ \ unsigned long ___haddr = __haddr & HPAGE_PMD_MASK; \ struct mm_struct *___mm = (__vma)->vm_mm; \ pmd_t ___pmd; \ \ ___pmd = pmdp_huge_clear_flush(__vma, __haddr, __pmd); \ mmu_notifier_invalidate_range(___mm, ___haddr, \ ___haddr + HPAGE_PMD_SIZE); \ \ ___pmd; \ }) #define pudp_huge_clear_flush_notify(__vma, __haddr, __pud) \ ({ \ unsigned long ___haddr = __haddr & HPAGE_PUD_MASK; \ struct mm_struct *___mm = (__vma)->vm_mm; \ pud_t ___pud; \ \ ___pud = pudp_huge_clear_flush(__vma, __haddr, __pud); \ mmu_notifier_invalidate_range(___mm, ___haddr, \ ___haddr + HPAGE_PUD_SIZE); \ \ ___pud; \ }) /* * set_pte_at_notify() sets the pte _after_ running the notifier. * This is safe to start by updating the secondary MMUs, because the primary MMU * pte invalidate must have already happened with a ptep_clear_flush() before * set_pte_at_notify() has been invoked. Updating the secondary MMUs first is * required when we change both the protection of the mapping from read-only to * read-write and the pfn (like during copy on write page faults). Otherwise the * old page would remain mapped readonly in the secondary MMUs after the new * page is already writable by some CPU through the primary MMU. */ #define set_pte_at_notify(__mm, __address, __ptep, __pte) \ ({ \ struct mm_struct *___mm = __mm; \ unsigned long ___address = __address; \ pte_t ___pte = __pte; \ \ mmu_notifier_change_pte(___mm, ___address, ___pte); \ set_pte_at(___mm, ___address, __ptep, ___pte); \ }) #else /* CONFIG_MMU_NOTIFIER */ struct mmu_notifier_range { unsigned long start; unsigned long end; }; static inline void _mmu_notifier_range_init(struct mmu_notifier_range *range, unsigned long start, unsigned long end) { range->start = start; range->end = end; } #define mmu_notifier_range_init(range,event,flags,vma,mm,start,end) \ _mmu_notifier_range_init(range, start, end) #define mmu_notifier_range_init_migrate(range, flags, vma, mm, start, end, \ pgmap) \ _mmu_notifier_range_init(range, start, end) static inline bool mmu_notifier_range_blockable(const struct mmu_notifier_range *range) { return true; } static inline int mm_has_notifiers(struct mm_struct *mm) { return 0; } static inline void mmu_notifier_release(struct mm_struct *mm) { } static inline int mmu_notifier_clear_flush_young(struct mm_struct *mm, unsigned long start, unsigned long end) { return 0; } static inline int mmu_notifier_test_young(struct mm_struct *mm, unsigned long address) { return 0; } static inline void mmu_notifier_change_pte(struct mm_struct *mm, unsigned long address, pte_t pte) { } static inline void mmu_notifier_invalidate_range_start(struct mmu_notifier_range *range) { } static inline int mmu_notifier_invalidate_range_start_nonblock(struct mmu_notifier_range *range) { return 0; } static inline void mmu_notifier_invalidate_range_end(struct mmu_notifier_range *range) { } static inline void mmu_notifier_invalidate_range_only_end(struct mmu_notifier_range *range) { } static inline void mmu_notifier_invalidate_range(struct mm_struct *mm, unsigned long start, unsigned long end) { } static inline void mmu_notifier_subscriptions_init(struct mm_struct *mm) { } static inline void mmu_notifier_subscriptions_destroy(struct mm_struct *mm) { } #define mmu_notifier_range_update_to_read_only(r) false #define ptep_clear_flush_young_notify ptep_clear_flush_young #define pmdp_clear_flush_young_notify pmdp_clear_flush_young #define ptep_clear_young_notify ptep_test_and_clear_young #define pmdp_clear_young_notify pmdp_test_and_clear_young #define ptep_clear_flush_notify ptep_clear_flush #define pmdp_huge_clear_flush_notify pmdp_huge_clear_flush #define pudp_huge_clear_flush_notify pudp_huge_clear_flush #define set_pte_at_notify set_pte_at static inline void mmu_notifier_synchronize(void) { } #endif /* CONFIG_MMU_NOTIFIER */ #endif /* _LINUX_MMU_NOTIFIER_H */
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 /* SPDX-License-Identifier: GPL-2.0 */ #ifndef __SOCK_DIAG_H__ #define __SOCK_DIAG_H__ #include <linux/netlink.h> #include <linux/user_namespace.h> #include <net/net_namespace.h> #include <net/sock.h> #include <uapi/linux/sock_diag.h> struct sk_buff; struct nlmsghdr; struct sock; struct sock_diag_handler { __u8 family; int (*dump)(struct sk_buff *skb, struct nlmsghdr *nlh); int (*get_info)(struct sk_buff *skb, struct sock *sk); int (*destroy)(struct sk_buff *skb, struct nlmsghdr *nlh); }; int sock_diag_register(const struct sock_diag_handler *h); void sock_diag_unregister(const struct sock_diag_handler *h); void sock_diag_register_inet_compat(int (*fn)(struct sk_buff *skb, struct nlmsghdr *nlh)); void sock_diag_unregister_inet_compat(int (*fn)(struct sk_buff *skb, struct nlmsghdr *nlh)); u64 __sock_gen_cookie(struct sock *sk); static inline u64 sock_gen_cookie(struct sock *sk) { u64 cookie; preempt_disable(); cookie = __sock_gen_cookie(sk); preempt_enable(); return cookie; } int sock_diag_check_cookie(struct sock *sk, const __u32 *cookie); void sock_diag_save_cookie(struct sock *sk, __u32 *cookie); int sock_diag_put_meminfo(struct sock *sk, struct sk_buff *skb, int attr); int sock_diag_put_filterinfo(bool may_report_filterinfo, struct sock *sk, struct sk_buff *skb, int attrtype); static inline enum sknetlink_groups sock_diag_destroy_group(const struct sock *sk) { switch (sk->sk_family) { case AF_INET: if (sk->sk_type == SOCK_RAW) return SKNLGRP_NONE; switch (sk->sk_protocol) { case IPPROTO_TCP: return SKNLGRP_INET_TCP_DESTROY; case IPPROTO_UDP: return SKNLGRP_INET_UDP_DESTROY; default: return SKNLGRP_NONE; } case AF_INET6: if (sk->sk_type == SOCK_RAW) return SKNLGRP_NONE; switch (sk->sk_protocol) { case IPPROTO_TCP: return SKNLGRP_INET6_TCP_DESTROY; case IPPROTO_UDP: return SKNLGRP_INET6_UDP_DESTROY; default: return SKNLGRP_NONE; } default: return SKNLGRP_NONE; } } static inline bool sock_diag_has_destroy_listeners(const struct sock *sk) { const struct net *n = sock_net(sk); const enum sknetlink_groups group = sock_diag_destroy_group(sk); return group != SKNLGRP_NONE && n->diag_nlsk && netlink_has_listeners(n->diag_nlsk, group); } void sock_diag_broadcast_destroy(struct sock *sk); int sock_diag_destroy(struct sock *sk, int err); #endif
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 /* SPDX-License-Identifier: GPL-2.0 */ #ifndef _LINUX_SCATTERLIST_H #define _LINUX_SCATTERLIST_H #include <linux/string.h> #include <linux/types.h> #include <linux/bug.h> #include <linux/mm.h> #include <asm/io.h> struct scatterlist { unsigned long page_link; unsigned int offset; unsigned int length; dma_addr_t dma_address; #ifdef CONFIG_NEED_SG_DMA_LENGTH unsigned int dma_length; #endif }; /* * Since the above length field is an unsigned int, below we define the maximum * length in bytes that can be stored in one scatterlist entry. */ #define SCATTERLIST_MAX_SEGMENT (UINT_MAX & PAGE_MASK) /* * These macros should be used after a dma_map_sg call has been done * to get bus addresses of each of the SG entries and their lengths. * You should only work with the number of sg entries dma_map_sg * returns, or alternatively stop on the first sg_dma_len(sg) which * is 0. */ #define sg_dma_address(sg) ((sg)->dma_address) #ifdef CONFIG_NEED_SG_DMA_LENGTH #define sg_dma_len(sg) ((sg)->dma_length) #else #define sg_dma_len(sg) ((sg)->length) #endif struct sg_table { struct scatterlist *sgl; /* the list */ unsigned int nents; /* number of mapped entries */ unsigned int orig_nents; /* original size of list */ }; /* * Notes on SG table design. * * We use the unsigned long page_link field in the scatterlist struct to place * the page pointer AND encode information about the sg table as well. The two * lower bits are reserved for this information. * * If bit 0 is set, then the page_link contains a pointer to the next sg * table list. Otherwise the next entry is at sg + 1. * * If bit 1 is set, then this sg entry is the last element in a list. * * See sg_next(). * */ #define SG_CHAIN 0x01UL #define SG_END 0x02UL /* * We overload the LSB of the page pointer to indicate whether it's * a valid sg entry, or whether it points to the start of a new scatterlist. * Those low bits are there for everyone! (thanks mason :-) */ #define sg_is_chain(sg) ((sg)->page_link & SG_CHAIN) #define sg_is_last(sg) ((sg)->page_link & SG_END) #define sg_chain_ptr(sg) \ ((struct scatterlist *) ((sg)->page_link & ~(SG_CHAIN | SG_END))) /** * sg_assign_page - Assign a given page to an SG entry * @sg: SG entry * @page: The page * * Description: * Assign page to sg entry. Also see sg_set_page(), the most commonly used * variant. * **/ static inline void sg_assign_page(struct scatterlist *sg, struct page *page) { unsigned long page_link = sg->page_link & (SG_CHAIN | SG_END); /* * In order for the low bit stealing approach to work, pages * must be aligned at a 32-bit boundary as a minimum. */ BUG_ON((unsigned long) page & (SG_CHAIN | SG_END)); #ifdef CONFIG_DEBUG_SG BUG_ON(sg_is_chain(sg)); #endif sg->page_link = page_link | (unsigned long) page; } /** * sg_set_page - Set sg entry to point at given page * @sg: SG entry * @page: The page * @len: Length of data * @offset: Offset into page * * Description: * Use this function to set an sg entry pointing at a page, never assign * the page directly. We encode sg table information in the lower bits * of the page pointer. See sg_page() for looking up the page belonging * to an sg entry. * **/ static inline void sg_set_page(struct scatterlist *sg, struct page *page, unsigned int len, unsigned int offset) { sg_assign_page(sg, page); sg->offset = offset; sg->length = len; } static inline struct page *sg_page(struct scatterlist *sg) { #ifdef CONFIG_DEBUG_SG BUG_ON(sg_is_chain(sg)); #endif return (struct page *)((sg)->page_link & ~(SG_CHAIN | SG_END)); } /** * sg_set_buf - Set sg entry to point at given data * @sg: SG entry * @buf: Data * @buflen: Data length * **/ static inline void sg_set_buf(struct scatterlist *sg, const void *buf, unsigned int buflen) { #ifdef CONFIG_DEBUG_SG BUG_ON(!virt_addr_valid(buf)); #endif sg_set_page(sg, virt_to_page(buf), buflen, offset_in_page(buf)); } /* * Loop over each sg element, following the pointer to a new list if necessary */ #define for_each_sg(sglist, sg, nr, __i) \ for (__i = 0, sg = (sglist); __i < (nr); __i++, sg = sg_next(sg)) /* * Loop over each sg element in the given sg_table object. */ #define for_each_sgtable_sg(sgt, sg, i) \ for_each_sg((sgt)->sgl, sg, (sgt)->orig_nents, i) /* * Loop over each sg element in the given *DMA mapped* sg_table object. * Please use sg_dma_address(sg) and sg_dma_len(sg) to extract DMA addresses * of the each element. */ #define for_each_sgtable_dma_sg(sgt, sg, i) \ for_each_sg((sgt)->sgl, sg, (sgt)->nents, i) static inline void __sg_chain(struct scatterlist *chain_sg, struct scatterlist *sgl) { /* * offset and length are unused for chain entry. Clear them. */ chain_sg->offset = 0; chain_sg->length = 0; /* * Set lowest bit to indicate a link pointer, and make sure to clear * the termination bit if it happens to be set. */ chain_sg->page_link = ((unsigned long) sgl | SG_CHAIN) & ~SG_END; } /** * sg_chain - Chain two sglists together * @prv: First scatterlist * @prv_nents: Number of entries in prv * @sgl: Second scatterlist * * Description: * Links @prv@ and @sgl@ together, to form a longer scatterlist. * **/ static inline void sg_chain(struct scatterlist *prv, unsigned int prv_nents, struct scatterlist *sgl) { __sg_chain(&prv[prv_nents - 1], sgl); } /** * sg_mark_end - Mark the end of the scatterlist * @sg: SG entryScatterlist * * Description: * Marks the passed in sg entry as the termination point for the sg * table. A call to sg_next() on this entry will return NULL. * **/ static inline void sg_mark_end(struct scatterlist *sg) { /* * Set termination bit, clear potential chain bit */ sg->page_link |= SG_END; sg->page_link &= ~SG_CHAIN; } /** * sg_unmark_end - Undo setting the end of the scatterlist * @sg: SG entryScatterlist * * Description: * Removes the termination marker from the given entry of the scatterlist. * **/ static inline void sg_unmark_end(struct scatterlist *sg) { sg->page_link &= ~SG_END; } /** * sg_phys - Return physical address of an sg entry * @sg: SG entry * * Description: * This calls page_to_phys() on the page in this sg entry, and adds the * sg offset. The caller must know that it is legal to call page_to_phys() * on the sg page. * **/ static inline dma_addr_t sg_phys(struct scatterlist *sg) { return page_to_phys(sg_page(sg)) + sg->offset; } /** * sg_virt - Return virtual address of an sg entry * @sg: SG entry * * Description: * This calls page_address() on the page in this sg entry, and adds the * sg offset. The caller must know that the sg page has a valid virtual * mapping. * **/ static inline void *sg_virt(struct scatterlist *sg) { return page_address(sg_page(sg)) + sg->offset; } /** * sg_init_marker - Initialize markers in sg table * @sgl: The SG table * @nents: Number of entries in table * **/ static inline void sg_init_marker(struct scatterlist *sgl, unsigned int nents) { sg_mark_end(&sgl[nents - 1]); } int sg_nents(struct scatterlist *sg); int sg_nents_for_len(struct scatterlist *sg, u64 len); struct scatterlist *sg_next(struct scatterlist *); struct scatterlist *sg_last(struct scatterlist *s, unsigned int); void sg_init_table(struct scatterlist *, unsigned int); void sg_init_one(struct scatterlist *, const void *, unsigned int); int sg_split(struct scatterlist *in, const int in_mapped_nents, const off_t skip, const int nb_splits, const size_t *split_sizes, struct scatterlist **out, int *out_mapped_nents, gfp_t gfp_mask); typedef struct scatterlist *(sg_alloc_fn)(unsigned int, gfp_t); typedef void (sg_free_fn)(struct scatterlist *, unsigned int); void __sg_free_table(struct sg_table *, unsigned int, unsigned int, sg_free_fn *); void sg_free_table(struct sg_table *); int __sg_alloc_table(struct sg_table *, unsigned int, unsigned int, struct scatterlist *, unsigned int, gfp_t, sg_alloc_fn *); int sg_alloc_table(struct sg_table *, unsigned int, gfp_t); struct scatterlist *__sg_alloc_table_from_pages(struct sg_table *sgt, struct page **pages, unsigned int n_pages, unsigned int offset, unsigned long size, unsigned int max_segment, struct scatterlist *prv, unsigned int left_pages, gfp_t gfp_mask); int sg_alloc_table_from_pages(struct sg_table *sgt, struct page **pages, unsigned int n_pages, unsigned int offset, unsigned long size, gfp_t gfp_mask); #ifdef CONFIG_SGL_ALLOC struct scatterlist *sgl_alloc_order(unsigned long long length, unsigned int order, bool chainable, gfp_t gfp, unsigned int *nent_p); struct scatterlist *sgl_alloc(unsigned long long length, gfp_t gfp, unsigned int *nent_p); void sgl_free_n_order(struct scatterlist *sgl, int nents, int order); void sgl_free_order(struct scatterlist *sgl, int order); void sgl_free(struct scatterlist *sgl); #endif /* CONFIG_SGL_ALLOC */ size_t sg_copy_buffer(struct scatterlist *sgl, unsigned int nents, void *buf, size_t buflen, off_t skip, bool to_buffer); size_t sg_copy_from_buffer(struct scatterlist *sgl, unsigned int nents, const void *buf, size_t buflen); size_t sg_copy_to_buffer(struct scatterlist *sgl, unsigned int nents, void *buf, size_t buflen); size_t sg_pcopy_from_buffer(struct scatterlist *sgl, unsigned int nents, const void *buf, size_t buflen, off_t skip); size_t sg_pcopy_to_buffer(struct scatterlist *sgl, unsigned int nents, void *buf, size_t buflen, off_t skip); size_t sg_zero_buffer(struct scatterlist *sgl, unsigned int nents, size_t buflen, off_t skip); /* * Maximum number of entries that will be allocated in one piece, if * a list larger than this is required then chaining will be utilized. */ #define SG_MAX_SINGLE_ALLOC (PAGE_SIZE / sizeof(struct scatterlist)) /* * The maximum number of SG segments that we will put inside a * scatterlist (unless chaining is used). Should ideally fit inside a * single page, to avoid a higher order allocation. We could define this * to SG_MAX_SINGLE_ALLOC to pack correctly at the highest order. The * minimum value is 32 */ #define SG_CHUNK_SIZE 128 /* * Like SG_CHUNK_SIZE, but for archs that have sg chaining. This limit * is totally arbitrary, a setting of 2048 will get you at least 8mb ios. */ #ifdef CONFIG_ARCH_NO_SG_CHAIN #define SG_MAX_SEGMENTS SG_CHUNK_SIZE #else #define SG_MAX_SEGMENTS 2048 #endif #ifdef CONFIG_SG_POOL void sg_free_table_chained(struct sg_table *table, unsigned nents_first_chunk); int sg_alloc_table_chained(struct sg_table *table, int nents, struct scatterlist *first_chunk, unsigned nents_first_chunk); #endif /* * sg page iterator * * Iterates over sg entries page-by-page. On each successful iteration, you * can call sg_page_iter_page(@piter) to get the current page. * @piter->sg will point to the sg holding this page and @piter->sg_pgoffset to * the page's page offset within the sg. The iteration will stop either when a * maximum number of sg entries was reached or a terminating sg * (sg_last(sg) == true) was reached. */ struct sg_page_iter { struct scatterlist *sg; /* sg holding the page */ unsigned int sg_pgoffset; /* page offset within the sg */ /* these are internal states, keep away */ unsigned int __nents; /* remaining sg entries */ int __pg_advance; /* nr pages to advance at the * next step */ }; /* * sg page iterator for DMA addresses * * This is the same as sg_page_iter however you can call * sg_page_iter_dma_address(@dma_iter) to get the page's DMA * address. sg_page_iter_page() cannot be called on this iterator. */ struct sg_dma_page_iter { struct sg_page_iter base; }; bool __sg_page_iter_next(struct sg_page_iter *piter); bool __sg_page_iter_dma_next(struct sg_dma_page_iter *dma_iter); void __sg_page_iter_start(struct sg_page_iter *piter, struct scatterlist *sglist, unsigned int nents, unsigned long pgoffset); /** * sg_page_iter_page - get the current page held by the page iterator * @piter: page iterator holding the page */ static inline struct page *sg_page_iter_page(struct sg_page_iter *piter) { return nth_page(sg_page(piter->sg), piter->sg_pgoffset); } /** * sg_page_iter_dma_address - get the dma address of the current page held by * the page iterator. * @dma_iter: page iterator holding the page */ static inline dma_addr_t sg_page_iter_dma_address(struct sg_dma_page_iter *dma_iter) { return sg_dma_address(dma_iter->base.sg) + (dma_iter->base.sg_pgoffset << PAGE_SHIFT); } /** * for_each_sg_page - iterate over the pages of the given sg list * @sglist: sglist to iterate over * @piter: page iterator to hold current page, sg, sg_pgoffset * @nents: maximum number of sg entries to iterate over * @pgoffset: starting page offset (in pages) * * Callers may use sg_page_iter_page() to get each page pointer. * In each loop it operates on PAGE_SIZE unit. */ #define for_each_sg_page(sglist, piter, nents, pgoffset) \ for (__sg_page_iter_start((piter), (sglist), (nents), (pgoffset)); \ __sg_page_iter_next(piter);) /** * for_each_sg_dma_page - iterate over the pages of the given sg list * @sglist: sglist to iterate over * @dma_iter: DMA page iterator to hold current page * @dma_nents: maximum number of sg entries to iterate over, this is the value * returned from dma_map_sg * @pgoffset: starting page offset (in pages) * * Callers may use sg_page_iter_dma_address() to get each page's DMA address. * In each loop it operates on PAGE_SIZE unit. */ #define for_each_sg_dma_page(sglist, dma_iter, dma_nents, pgoffset) \ for (__sg_page_iter_start(&(dma_iter)->base, sglist, dma_nents, \ pgoffset); \ __sg_page_iter_dma_next(dma_iter);) /** * for_each_sgtable_page - iterate over all pages in the sg_table object * @sgt: sg_table object to iterate over * @piter: page iterator to hold current page * @pgoffset: starting page offset (in pages) * * Iterates over the all memory pages in the buffer described by * a scatterlist stored in the given sg_table object. * See also for_each_sg_page(). In each loop it operates on PAGE_SIZE unit. */ #define for_each_sgtable_page(sgt, piter, pgoffset) \ for_each_sg_page((sgt)->sgl, piter, (sgt)->orig_nents, pgoffset) /** * for_each_sgtable_dma_page - iterate over the DMA mapped sg_table object * @sgt: sg_table object to iterate over * @dma_iter: DMA page iterator to hold current page * @pgoffset: starting page offset (in pages) * * Iterates over the all DMA mapped pages in the buffer described by * a scatterlist stored in the given sg_table object. * See also for_each_sg_dma_page(). In each loop it operates on PAGE_SIZE * unit. */ #define for_each_sgtable_dma_page(sgt, dma_iter, pgoffset) \ for_each_sg_dma_page((sgt)->sgl, dma_iter, (sgt)->nents, pgoffset) /* * Mapping sg iterator * * Iterates over sg entries mapping page-by-page. On each successful * iteration, @miter->page points to the mapped page and * @miter->length bytes of data can be accessed at @miter->addr. As * long as an interation is enclosed between start and stop, the user * is free to choose control structure and when to stop. * * @miter->consumed is set to @miter->length on each iteration. It * can be adjusted if the user can't consume all the bytes in one go. * Also, a stopped iteration can be resumed by calling next on it. * This is useful when iteration needs to release all resources and * continue later (e.g. at the next interrupt). */ #define SG_MITER_ATOMIC (1 << 0) /* use kmap_atomic */ #define SG_MITER_TO_SG (1 << 1) /* flush back to phys on unmap */ #define SG_MITER_FROM_SG (1 << 2) /* nop */ struct sg_mapping_iter { /* the following three fields can be accessed directly */ struct page *page; /* currently mapped page */ void *addr; /* pointer to the mapped area */ size_t length; /* length of the mapped area */ size_t consumed; /* number of consumed bytes */ struct sg_page_iter piter; /* page iterator */ /* these are internal states, keep away */ unsigned int __offset; /* offset within page */ unsigned int __remaining; /* remaining bytes on page */ unsigned int __flags; }; void sg_miter_start(struct sg_mapping_iter *miter, struct scatterlist *sgl, unsigned int nents, unsigned int flags); bool sg_miter_skip(struct sg_mapping_iter *miter, off_t offset); bool sg_miter_next(struct sg_mapping_iter *miter); void sg_miter_stop(struct sg_mapping_iter *miter); #endif /* _LINUX_SCATTERLIST_H */
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 /* SPDX-License-Identifier: GPL-2.0 */ #ifndef _ASM_X86_SPECIAL_INSNS_H #define _ASM_X86_SPECIAL_INSNS_H #ifdef __KERNEL__ #include <asm/nops.h> #include <asm/processor-flags.h> #include <linux/irqflags.h> #include <linux/jump_label.h> /* * The compiler should not reorder volatile asm statements with respect to each * other: they should execute in program order. However GCC 4.9.x and 5.x have * a bug (which was fixed in 8.1, 7.3 and 6.5) where they might reorder * volatile asm. The write functions are not affected since they have memory * clobbers preventing reordering. To prevent reads from being reordered with * respect to writes, use a dummy memory operand. */ #define __FORCE_ORDER "m"(*(unsigned int *)0x1000UL) void native_write_cr0(unsigned long val); static inline unsigned long native_read_cr0(void) { unsigned long val; asm volatile("mov %%cr0,%0\n\t" : "=r" (val) : __FORCE_ORDER); return val; } static __always_inline unsigned long native_read_cr2(void) { unsigned long val; asm volatile("mov %%cr2,%0\n\t" : "=r" (val) : __FORCE_ORDER); return val; } static __always_inline void native_write_cr2(unsigned long val) { asm volatile("mov %0,%%cr2": : "r" (val) : "memory"); } static inline unsigned long __native_read_cr3(void) { unsigned long val; asm volatile("mov %%cr3,%0\n\t" : "=r" (val) : __FORCE_ORDER); return val; } static inline void native_write_cr3(unsigned long val) { asm volatile("mov %0,%%cr3": : "r" (val) : "memory"); } static inline unsigned long native_read_cr4(void) { unsigned long val; #ifdef CONFIG_X86_32 /* * This could fault if CR4 does not exist. Non-existent CR4 * is functionally equivalent to CR4 == 0. Keep it simple and pretend * that CR4 == 0 on CPUs that don't have CR4. */ asm volatile("1: mov %%cr4, %0\n" "2:\n" _ASM_EXTABLE(1b, 2b) : "=r" (val) : "0" (0), __FORCE_ORDER); #else /* CR4 always exists on x86_64. */ asm volatile("mov %%cr4,%0\n\t" : "=r" (val) : __FORCE_ORDER); #endif return val; } void native_write_cr4(unsigned long val); #ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS static inline u32 rdpkru(void) { u32 ecx = 0; u32 edx, pkru; /* * "rdpkru" instruction. Places PKRU contents in to EAX, * clears EDX and requires that ecx=0. */ asm volatile(".byte 0x0f,0x01,0xee\n\t" : "=a" (pkru), "=d" (edx) : "c" (ecx)); return pkru; } static inline void wrpkru(u32 pkru) { u32 ecx = 0, edx = 0; /* * "wrpkru" instruction. Loads contents in EAX to PKRU, * requires that ecx = edx = 0. */ asm volatile(".byte 0x0f,0x01,0xef\n\t" : : "a" (pkru), "c"(ecx), "d"(edx)); } static inline void __write_pkru(u32 pkru) { /* * WRPKRU is relatively expensive compared to RDPKRU. * Avoid WRPKRU when it would not change the value. */ if (pkru == rdpkru()) return; wrpkru(pkru); } #else static inline u32 rdpkru(void) { return 0; } static inline void __write_pkru(u32 pkru) { } #endif static inline void native_wbinvd(void) { asm volatile("wbinvd": : :"memory"); } extern asmlinkage void asm_load_gs_index(unsigned int selector); static inline void native_load_gs_index(unsigned int selector) { unsigned long flags; local_irq_save(flags); asm_load_gs_index(selector); local_irq_restore(flags); } static inline unsigned long __read_cr4(void) { return native_read_cr4(); } #ifdef CONFIG_PARAVIRT_XXL #include <asm/paravirt.h> #else static inline unsigned long read_cr0(void) { return native_read_cr0(); } static inline void write_cr0(unsigned long x) { native_write_cr0(x); } static __always_inline unsigned long read_cr2(void) { return native_read_cr2(); } static __always_inline void write_cr2(unsigned long x) { native_write_cr2(x); } /* * Careful! CR3 contains more than just an address. You probably want * read_cr3_pa() instead. */ static inline unsigned long __read_cr3(void) { return __native_read_cr3(); } static inline void write_cr3(unsigned long x) { native_write_cr3(x); } static inline void __write_cr4(unsigned long x) { native_write_cr4(x); } static inline void wbinvd(void) { native_wbinvd(); } #ifdef CONFIG_X86_64 static inline void load_gs_index(unsigned int selector) { native_load_gs_index(selector); } #endif #endif /* CONFIG_PARAVIRT_XXL */ static inline void clflush(volatile void *__p) { asm volatile("clflush %0" : "+m" (*(volatile char __force *)__p)); } static inline void clflushopt(volatile void *__p) { alternative_io(".byte " __stringify(NOP_DS_PREFIX) "; clflush %P0", ".byte 0x66; clflush %P0", X86_FEATURE_CLFLUSHOPT, "+m" (*(volatile char __force *)__p)); } static inline void clwb(volatile void *__p) { volatile struct { char x[64]; } *p = __p; asm volatile(ALTERNATIVE_2( ".byte " __stringify(NOP_DS_PREFIX) "; clflush (%[pax])", ".byte 0x66; clflush (%[pax])", /* clflushopt (%%rax) */ X86_FEATURE_CLFLUSHOPT, ".byte 0x66, 0x0f, 0xae, 0x30", /* clwb (%%rax) */ X86_FEATURE_CLWB) : [p] "+m" (*p) : [pax] "a" (p)); } #define nop() asm volatile ("nop") static inline void serialize(void) { /* Instruction opcode for SERIALIZE; supported in binutils >= 2.35. */ asm volatile(".byte 0xf, 0x1, 0xe8" ::: "memory"); } /* The dst parameter must be 64-bytes aligned */ static inline void movdir64b(void *dst, const void *src) { const struct { char _[64]; } *__src = src; struct { char _[64]; } *__dst = dst; /* * MOVDIR64B %(rdx), rax. * * Both __src and __dst must be memory constraints in order to tell the * compiler that no other memory accesses should be reordered around * this one. * * Also, both must be supplied as lvalues because this tells * the compiler what the object is (its size) the instruction accesses. * I.e., not the pointers but what they point to, thus the deref'ing '*'. */ asm volatile(".byte 0x66, 0x0f, 0x38, 0xf8, 0x02" : "+m" (*__dst) : "m" (*__src), "a" (__dst), "d" (__src)); } /** * enqcmds - Enqueue a command in supervisor (CPL0) mode * @dst: destination, in MMIO space (must be 512-bit aligned) * @src: 512 bits memory operand * * The ENQCMDS instruction allows software to write a 512-bit command to * a 512-bit-aligned special MMIO region that supports the instruction. * A return status is loaded into the ZF flag in the RFLAGS register. * ZF = 0 equates to success, and ZF = 1 indicates retry or error. * * This function issues the ENQCMDS instruction to submit data from * kernel space to MMIO space, in a unit of 512 bits. Order of data access * is not guaranteed, nor is a memory barrier performed afterwards. It * returns 0 on success and -EAGAIN on failure. * * Warning: Do not use this helper unless your driver has checked that the * ENQCMDS instruction is supported on the platform and the device accepts * ENQCMDS. */ static inline int enqcmds(void __iomem *dst, const void *src) { const struct { char _[64]; } *__src = src; struct { char _[64]; } __iomem *__dst = dst; bool zf; /* * ENQCMDS %(rdx), rax * * See movdir64b()'s comment on operand specification. */ asm volatile(".byte 0xf3, 0x0f, 0x38, 0xf8, 0x02, 0x66, 0x90" CC_SET(z) : CC_OUT(z) (zf), "+m" (*__dst) : "m" (*__src), "a" (__dst), "d" (__src)); /* Submission failure is indicated via EFLAGS.ZF=1 */ if (zf) return -EAGAIN; return 0; } #endif /* __KERNEL__ */ #endif /* _ASM_X86_SPECIAL_INSNS_H */
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 /* SPDX-License-Identifier: GPL-2.0 */ #ifndef __NET_FRAG_H__ #define __NET_FRAG_H__ #include <linux/rhashtable-types.h> #include <linux/completion.h> /* Per netns frag queues directory */ struct fqdir { /* sysctls */ long high_thresh; long low_thresh; int timeout; int max_dist; struct inet_frags *f; struct net *net; bool dead; struct rhashtable rhashtable ____cacheline_aligned_in_smp; /* Keep atomic mem on separate cachelines in structs that include it */ atomic_long_t mem ____cacheline_aligned_in_smp; struct work_struct destroy_work; }; /** * fragment queue flags * * @INET_FRAG_FIRST_IN: first fragment has arrived * @INET_FRAG_LAST_IN: final fragment has arrived * @INET_FRAG_COMPLETE: frag queue has been processed and is due for destruction * @INET_FRAG_HASH_DEAD: inet_frag_kill() has not removed fq from rhashtable */ enum { INET_FRAG_FIRST_IN = BIT(0), INET_FRAG_LAST_IN = BIT(1), INET_FRAG_COMPLETE = BIT(2), INET_FRAG_HASH_DEAD = BIT(3), }; struct frag_v4_compare_key { __be32 saddr; __be32 daddr; u32 user; u32 vif; __be16 id; u16 protocol; }; struct frag_v6_compare_key { struct in6_addr saddr; struct in6_addr daddr; u32 user; __be32 id; u32 iif; }; /** * struct inet_frag_queue - fragment queue * * @node: rhash node * @key: keys identifying this frag. * @timer: queue expiration timer * @lock: spinlock protecting this frag * @refcnt: reference count of the queue * @rb_fragments: received fragments rb-tree root * @fragments_tail: received fragments tail * @last_run_head: the head of the last "run". see ip_fragment.c * @stamp: timestamp of the last received fragment * @len: total length of the original datagram * @meat: length of received fragments so far * @flags: fragment queue flags * @max_size: maximum received fragment size * @fqdir: pointer to struct fqdir * @rcu: rcu head for freeing deferall */ struct inet_frag_queue { struct rhash_head node; union { struct frag_v4_compare_key v4; struct frag_v6_compare_key v6; } key; struct timer_list timer; spinlock_t lock; refcount_t refcnt; struct rb_root rb_fragments; struct sk_buff *fragments_tail; struct sk_buff *last_run_head; ktime_t stamp; int len; int meat; __u8 flags; u16 max_size; struct fqdir *fqdir; struct rcu_head rcu; }; struct inet_frags { unsigned int qsize; void (*constructor)(struct inet_frag_queue *q, const void *arg); void (*destructor)(struct inet_frag_queue *); void (*frag_expire)(struct timer_list *t); struct kmem_cache *frags_cachep; const char *frags_cache_name; struct rhashtable_params rhash_params; refcount_t refcnt; struct completion completion; }; int inet_frags_init(struct inet_frags *); void inet_frags_fini(struct inet_frags *); int fqdir_init(struct fqdir **fqdirp, struct inet_frags *f, struct net *net); static inline void fqdir_pre_exit(struct fqdir *fqdir) { fqdir->high_thresh = 0; /* prevent creation of new frags */ fqdir->dead = true; } void fqdir_exit(struct fqdir *fqdir); void inet_frag_kill(struct inet_frag_queue *q); void inet_frag_destroy(struct inet_frag_queue *q); struct inet_frag_queue *inet_frag_find(struct fqdir *fqdir, void *key); /* Free all skbs in the queue; return the sum of their truesizes. */ unsigned int inet_frag_rbtree_purge(struct rb_root *root); static inline void inet_frag_put(struct inet_frag_queue *q) { if (refcount_dec_and_test(&q->refcnt)) inet_frag_destroy(q); } /* Memory Tracking Functions. */ static inline long frag_mem_limit(const struct fqdir *fqdir) { return atomic_long_read(&fqdir->mem); } static inline void sub_frag_mem_limit(struct fqdir *fqdir, long val) { atomic_long_sub(val, &fqdir->mem); } static inline void add_frag_mem_limit(struct fqdir *fqdir, long val) { atomic_long_add(val, &fqdir->mem); } /* RFC 3168 support : * We want to check ECN values of all fragments, do detect invalid combinations. * In ipq->ecn, we store the OR value of each ip4_frag_ecn() fragment value. */ #define IPFRAG_ECN_NOT_ECT 0x01 /* one frag had ECN_NOT_ECT */ #define IPFRAG_ECN_ECT_1 0x02 /* one frag had ECN_ECT_1 */ #define IPFRAG_ECN_ECT_0 0x04 /* one frag had ECN_ECT_0 */ #define IPFRAG_ECN_CE 0x08 /* one frag had ECN_CE */ extern const u8 ip_frag_ecn_table[16]; /* Return values of inet_frag_queue_insert() */ #define IPFRAG_OK 0 #define IPFRAG_DUP 1 #define IPFRAG_OVERLAP 2 int inet_frag_queue_insert(struct inet_frag_queue *q, struct sk_buff *skb, int offset, int end); void *inet_frag_reasm_prepare(struct inet_frag_queue *q, struct sk_buff *skb, struct sk_buff *parent); void inet_frag_reasm_finish(struct inet_frag_queue *q, struct sk_buff *head, void *reasm_data, bool try_coalesce); struct sk_buff *inet_frag_pull_head(struct inet_frag_queue *q); #endif
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 /* SPDX-License-Identifier: GPL-2.0 */ #ifndef _ASM_X86_ATOMIC_H #define _ASM_X86_ATOMIC_H #include <linux/compiler.h> #include <linux/types.h> #include <asm/alternative.h> #include <asm/cmpxchg.h> #include <asm/rmwcc.h> #include <asm/barrier.h> /* * Atomic operations that C can't guarantee us. Useful for * resource counting etc.. */ /** * arch_atomic_read - read atomic variable * @v: pointer of type atomic_t * * Atomically reads the value of @v. */ static __always_inline int arch_atomic_read(const atomic_t *v) { /* * Note for KASAN: we deliberately don't use READ_ONCE_NOCHECK() here, * it's non-inlined function that increases binary size and stack usage. */ return __READ_ONCE((v)->counter); } /** * arch_atomic_set - set atomic variable * @v: pointer of type atomic_t * @i: required value * * Atomically sets the value of @v to @i. */ static __always_inline void arch_atomic_set(atomic_t *v, int i) { __WRITE_ONCE(v->counter, i); } /** * arch_atomic_add - add integer to atomic variable * @i: integer value to add * @v: pointer of type atomic_t * * Atomically adds @i to @v. */ static __always_inline void arch_atomic_add(int i, atomic_t *v) { asm volatile(LOCK_PREFIX "addl %1,%0" : "+m" (v->counter) : "ir" (i) : "memory"); } /** * arch_atomic_sub - subtract integer from atomic variable * @i: integer value to subtract * @v: pointer of type atomic_t * * Atomically subtracts @i from @v. */ static __always_inline void arch_atomic_sub(int i, atomic_t *v) { asm volatile(LOCK_PREFIX "subl %1,%0" : "+m" (v->counter) : "ir" (i) : "memory"); } /** * arch_atomic_sub_and_test - subtract value from variable and test result * @i: integer value to subtract * @v: pointer of type atomic_t * * Atomically subtracts @i from @v and returns * true if the result is zero, or false for all * other cases. */ static __always_inline bool arch_atomic_sub_and_test(int i, atomic_t *v) { return GEN_BINARY_RMWcc(LOCK_PREFIX "subl", v->counter, e, "er", i); } #define arch_atomic_sub_and_test arch_atomic_sub_and_test /** * arch_atomic_inc - increment atomic variable * @v: pointer of type atomic_t * * Atomically increments @v by 1. */ static __always_inline void arch_atomic_inc(atomic_t *v) { asm volatile(LOCK_PREFIX "incl %0" : "+m" (v->counter) :: "memory"); } #define arch_atomic_inc arch_atomic_inc /** * arch_atomic_dec - decrement atomic variable * @v: pointer of type atomic_t * * Atomically decrements @v by 1. */ static __always_inline void arch_atomic_dec(atomic_t *v) { asm volatile(LOCK_PREFIX "decl %0" : "+m" (v->counter) :: "memory"); } #define arch_atomic_dec arch_atomic_dec /** * arch_atomic_dec_and_test - decrement and test * @v: pointer of type atomic_t * * Atomically decrements @v by 1 and * returns true if the result is 0, or false for all other * cases. */ static __always_inline bool arch_atomic_dec_and_test(atomic_t *v) { return GEN_UNARY_RMWcc(LOCK_PREFIX "decl", v->counter, e); } #define arch_atomic_dec_and_test arch_atomic_dec_and_test /** * arch_atomic_inc_and_test - increment and test * @v: pointer of type atomic_t * * Atomically increments @v by 1 * and returns true if the result is zero, or false for all * other cases. */ static __always_inline bool arch_atomic_inc_and_test(atomic_t *v) { return GEN_UNARY_RMWcc(LOCK_PREFIX "incl", v->counter, e); } #define arch_atomic_inc_and_test arch_atomic_inc_and_test /** * arch_atomic_add_negative - add and test if negative * @i: integer value to add * @v: pointer of type atomic_t * * Atomically adds @i to @v and returns true * if the result is negative, or false when * result is greater than or equal to zero. */ static __always_inline bool arch_atomic_add_negative(int i, atomic_t *v) { return GEN_BINARY_RMWcc(LOCK_PREFIX "addl", v->counter, s, "er", i); } #define arch_atomic_add_negative arch_atomic_add_negative /** * arch_atomic_add_return - add integer and return * @i: integer value to add * @v: pointer of type atomic_t * * Atomically adds @i to @v and returns @i + @v */ static __always_inline int arch_atomic_add_return(int i, atomic_t *v) { return i + xadd(&v->counter, i); } #define arch_atomic_add_return arch_atomic_add_return /** * arch_atomic_sub_return - subtract integer and return * @v: pointer of type atomic_t * @i: integer value to subtract * * Atomically subtracts @i from @v and returns @v - @i */ static __always_inline int arch_atomic_sub_return(int i, atomic_t *v) { return arch_atomic_add_return(-i, v); } #define arch_atomic_sub_return arch_atomic_sub_return static __always_inline int arch_atomic_fetch_add(int i, atomic_t *v) { return xadd(&v->counter, i); } #define arch_atomic_fetch_add arch_atomic_fetch_add static __always_inline int arch_atomic_fetch_sub(int i, atomic_t *v) { return xadd(&v->counter, -i); } #define arch_atomic_fetch_sub arch_atomic_fetch_sub static __always_inline int arch_atomic_cmpxchg(atomic_t *v, int old, int new) { return arch_cmpxchg(&v->counter, old, new); } #define arch_atomic_cmpxchg arch_atomic_cmpxchg static __always_inline bool arch_atomic_try_cmpxchg(atomic_t *v, int *old, int new) { return try_cmpxchg(&v->counter, old, new); } #define arch_atomic_try_cmpxchg arch_atomic_try_cmpxchg static __always_inline int arch_atomic_xchg(atomic_t *v, int new) { return arch_xchg(&v->counter, new); } #define arch_atomic_xchg arch_atomic_xchg static __always_inline void arch_atomic_and(int i, atomic_t *v) { asm volatile(LOCK_PREFIX "andl %1,%0" : "+m" (v->counter) : "ir" (i) : "memory"); } static __always_inline int arch_atomic_fetch_and(int i, atomic_t *v) { int val = arch_atomic_read(v); do { } while (!arch_atomic_try_cmpxchg(v, &val, val & i)); return val; } #define arch_atomic_fetch_and arch_atomic_fetch_and static __always_inline void arch_atomic_or(int i, atomic_t *v) { asm volatile(LOCK_PREFIX "orl %1,%0" : "+m" (v->counter) : "ir" (i) : "memory"); } static __always_inline int arch_atomic_fetch_or(int i, atomic_t *v) { int val = arch_atomic_read(v); do { } while (!arch_atomic_try_cmpxchg(v, &val, val | i)); return val; } #define arch_atomic_fetch_or arch_atomic_fetch_or static __always_inline void arch_atomic_xor(int i, atomic_t *v) { asm volatile(LOCK_PREFIX "xorl %1,%0" : "+m" (v->counter) : "ir" (i) : "memory"); } static __always_inline int arch_atomic_fetch_xor(int i, atomic_t *v) { int val = arch_atomic_read(v); do { } while (!arch_atomic_try_cmpxchg(v, &val, val ^ i)); return val; } #define arch_atomic_fetch_xor arch_atomic_fetch_xor #ifdef CONFIG_X86_32 # include <asm/atomic64_32.h> #else # include <asm/atomic64_64.h> #endif #define ARCH_ATOMIC #endif /* _ASM_X86_ATOMIC_H */
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 /* SPDX-License-Identifier: GPL-2.0-only */ #ifndef _NET_ETHTOOL_NETLINK_H #define _NET_ETHTOOL_NETLINK_H #include <linux/ethtool_netlink.h> #include <linux/netdevice.h> #include <net/genetlink.h> #include <net/sock.h> struct ethnl_req_info; int ethnl_parse_header_dev_get(struct ethnl_req_info *req_info, const struct nlattr *nest, struct net *net, struct netlink_ext_ack *extack, bool require_dev); int ethnl_fill_reply_header(struct sk_buff *skb, struct net_device *dev, u16 attrtype); struct sk_buff *ethnl_reply_init(size_t payload, struct net_device *dev, u8 cmd, u16 hdr_attrtype, struct genl_info *info, void **ehdrp); void *ethnl_dump_put(struct sk_buff *skb, struct netlink_callback *cb, u8 cmd); void *ethnl_bcastmsg_put(struct sk_buff *skb, u8 cmd); int ethnl_multicast(struct sk_buff *skb, struct net_device *dev); /** * ethnl_strz_size() - calculate attribute length for fixed size string * @s: ETH_GSTRING_LEN sized string (may not be null terminated) * * Return: total length of an attribute with null terminated string from @s */ static inline int ethnl_strz_size(const char *s) { return nla_total_size(strnlen(s, ETH_GSTRING_LEN) + 1); } /** * ethnl_put_strz() - put string attribute with fixed size string * @skb: skb with the message * @attrype: attribute type * @s: ETH_GSTRING_LEN sized string (may not be null terminated) * * Puts an attribute with null terminated string from @s into the message. * * Return: 0 on success, negative error code on failure */ static inline int ethnl_put_strz(struct sk_buff *skb, u16 attrtype, const char *s) { unsigned int len = strnlen(s, ETH_GSTRING_LEN); struct nlattr *attr; attr = nla_reserve(skb, attrtype, len + 1); if (!attr) return -EMSGSIZE; memcpy(nla_data(attr), s, len); ((char *)nla_data(attr))[len] = '\0'; return 0; } /** * ethnl_update_u32() - update u32 value from NLA_U32 attribute * @dst: value to update * @attr: netlink attribute with new value or null * @mod: pointer to bool for modification tracking * * Copy the u32 value from NLA_U32 netlink attribute @attr into variable * pointed to by @dst; do nothing if @attr is null. Bool pointed to by @mod * is set to true if this function changed the value of *dst, otherwise it * is left as is. */ static inline void ethnl_update_u32(u32 *dst, const struct nlattr *attr, bool *mod) { u32 val; if (!attr) return; val = nla_get_u32(attr); if (*dst == val) return; *dst = val; *mod = true; } /** * ethnl_update_u8() - update u8 value from NLA_U8 attribute * @dst: value to update * @attr: netlink attribute with new value or null * @mod: pointer to bool for modification tracking * * Copy the u8 value from NLA_U8 netlink attribute @attr into variable * pointed to by @dst; do nothing if @attr is null. Bool pointed to by @mod * is set to true if this function changed the value of *dst, otherwise it * is left as is. */ static inline void ethnl_update_u8(u8 *dst, const struct nlattr *attr, bool *mod) { u8 val; if (!attr) return; val = nla_get_u8(attr); if (*dst == val) return; *dst = val; *mod = true; } /** * ethnl_update_bool32() - update u32 used as bool from NLA_U8 attribute * @dst: value to update * @attr: netlink attribute with new value or null * @mod: pointer to bool for modification tracking * * Use the u8 value from NLA_U8 netlink attribute @attr to set u32 variable * pointed to by @dst to 0 (if zero) or 1 (if not); do nothing if @attr is * null. Bool pointed to by @mod is set to true if this function changed the * logical value of *dst, otherwise it is left as is. */ static inline void ethnl_update_bool32(u32 *dst, const struct nlattr *attr, bool *mod) { u8 val; if (!attr) return; val = !!nla_get_u8(attr); if (!!*dst == val) return; *dst = val; *mod = true; } /** * ethnl_update_binary() - update binary data from NLA_BINARY atribute * @dst: value to update * @len: destination buffer length * @attr: netlink attribute with new value or null * @mod: pointer to bool for modification tracking * * Use the u8 value from NLA_U8 netlink attribute @attr to rewrite data block * of length @len at @dst by attribute payload; do nothing if @attr is null. * Bool pointed to by @mod is set to true if this function changed the logical * value of *dst, otherwise it is left as is. */ static inline void ethnl_update_binary(void *dst, unsigned int len, const struct nlattr *attr, bool *mod) { if (!attr) return; if (nla_len(attr) < len) len = nla_len(attr); if (!memcmp(dst, nla_data(attr), len)) return; memcpy(dst, nla_data(attr), len); *mod = true; } /** * ethnl_update_bitfield32() - update u32 value from NLA_BITFIELD32 attribute * @dst: value to update * @attr: netlink attribute with new value or null * @mod: pointer to bool for modification tracking * * Update bits in u32 value which are set in attribute's mask to values from * attribute's value. Do nothing if @attr is null or the value wouldn't change; * otherwise, set bool pointed to by @mod to true. */ static inline void ethnl_update_bitfield32(u32 *dst, const struct nlattr *attr, bool *mod) { struct nla_bitfield32 change; u32 newval; if (!attr) return; change = nla_get_bitfield32(attr); newval = (*dst & ~change.selector) | (change.value & change.selector); if (*dst == newval) return; *dst = newval; *mod = true; } /** * ethnl_reply_header_size() - total size of reply header * * This is an upper estimate so that we do not need to hold RTNL lock longer * than necessary (to prevent rename between size estimate and composing the * message). Accounts only for device ifindex and name as those are the only * attributes ethnl_fill_reply_header() puts into the reply header. */ static inline unsigned int ethnl_reply_header_size(void) { return nla_total_size(nla_total_size(sizeof(u32)) + nla_total_size(IFNAMSIZ)); } /* GET request handling */ /* Unified processing of GET requests uses two data structures: request info * and reply data. Request info holds information parsed from client request * and its stays constant through all request processing. Reply data holds data * retrieved from ethtool_ops callbacks or other internal sources which is used * to compose the reply. When processing a dump request, request info is filled * only once (when the request message is parsed) but reply data is filled for * each reply message. * * Both structures consist of part common for all request types (struct * ethnl_req_info and struct ethnl_reply_data defined below) and optional * parts specific for each request type. Common part always starts at offset 0. */ /** * struct ethnl_req_info - base type of request information for GET requests * @dev: network device the request is for (may be null) * @flags: request flags common for all request types * * This is a common base for request specific structures holding data from * parsed userspace request. These always embed struct ethnl_req_info at * zero offset. */ struct ethnl_req_info { struct net_device *dev; u32 flags; }; /** * struct ethnl_reply_data - base type of reply data for GET requests * @dev: device for current reply message; in single shot requests it is * equal to &ethnl_req_info.dev; in dumps it's different for each * reply message * * This is a common base for request specific structures holding data for * kernel reply message. These always embed struct ethnl_reply_data at zero * offset. */ struct ethnl_reply_data { struct net_device *dev; }; static inline int ethnl_ops_begin(struct net_device *dev) { if (dev && dev->reg_state == NETREG_UNREGISTERING) return -ENODEV; if (dev && dev->ethtool_ops->begin) return dev->ethtool_ops->begin(dev); else return 0; } static inline void ethnl_ops_complete(struct net_device *dev) { if (dev && dev->ethtool_ops->complete) dev->ethtool_ops->complete(dev); } /** * struct ethnl_request_ops - unified handling of GET requests * @request_cmd: command id for request (GET) * @reply_cmd: command id for reply (GET_REPLY) * @hdr_attr: attribute type for request header * @req_info_size: size of request info * @reply_data_size: size of reply data * @allow_nodev_do: allow non-dump request with no device identification * @parse_request: * Parse request except common header (struct ethnl_req_info). Common * header is already filled on entry, the rest up to @repdata_offset * is zero initialized. This callback should only modify type specific * request info by parsed attributes from request message. * @prepare_data: * Retrieve and prepare data needed to compose a reply message. Calls to * ethtool_ops handlers are limited to this callback. Common reply data * (struct ethnl_reply_data) is filled on entry, type specific part after * it is zero initialized. This callback should only modify the type * specific part of reply data. Device identification from struct * ethnl_reply_data is to be used as for dump requests, it iterates * through network devices while dev member of struct ethnl_req_info * points to the device from client request. * @reply_size: * Estimate reply message size. Returned value must be sufficient for * message payload without common reply header. The callback may returned * estimate higher than actual message size if exact calculation would * not be worth the saved memory space. * @fill_reply: * Fill reply message payload (except for common header) from reply data. * The callback must not generate more payload than previously called * ->reply_size() estimated. * @cleanup_data: * Optional cleanup called when reply data is no longer needed. Can be * used e.g. to free any additional data structures outside the main * structure which were allocated by ->prepare_data(). When processing * dump requests, ->cleanup() is called for each message. * * Description of variable parts of GET request handling when using the * unified infrastructure. When used, a pointer to an instance of this * structure is to be added to &ethnl_default_requests array and generic * handlers ethnl_default_doit(), ethnl_default_dumpit(), * ethnl_default_start() and ethnl_default_done() used in @ethtool_genl_ops; * ethnl_default_notify() can be used in @ethnl_notify_handlers to send * notifications of the corresponding type. */ struct ethnl_request_ops { u8 request_cmd; u8 reply_cmd; u16 hdr_attr; unsigned int req_info_size; unsigned int reply_data_size; bool allow_nodev_do; int (*parse_request)(struct ethnl_req_info *req_info, struct nlattr **tb, struct netlink_ext_ack *extack); int (*prepare_data)(const struct ethnl_req_info *req_info, struct ethnl_reply_data *reply_data, struct genl_info *info); int (*reply_size)(const struct ethnl_req_info *req_info, const struct ethnl_reply_data *reply_data); int (*fill_reply)(struct sk_buff *skb, const struct ethnl_req_info *req_info, const struct ethnl_reply_data *reply_data); void (*cleanup_data)(struct ethnl_reply_data *reply_data); }; /* request handlers */ extern const struct ethnl_request_ops ethnl_strset_request_ops; extern const struct ethnl_request_ops ethnl_linkinfo_request_ops; extern const struct ethnl_request_ops ethnl_linkmodes_request_ops; extern const struct ethnl_request_ops ethnl_linkstate_request_ops; extern const struct ethnl_request_ops ethnl_debug_request_ops; extern const struct ethnl_request_ops ethnl_wol_request_ops; extern const struct ethnl_request_ops ethnl_features_request_ops; extern const struct ethnl_request_ops ethnl_privflags_request_ops; extern const struct ethnl_request_ops ethnl_rings_request_ops; extern const struct ethnl_request_ops ethnl_channels_request_ops; extern const struct ethnl_request_ops ethnl_coalesce_request_ops; extern const struct ethnl_request_ops ethnl_pause_request_ops; extern const struct ethnl_request_ops ethnl_eee_request_ops; extern const struct ethnl_request_ops ethnl_tsinfo_request_ops; extern const struct nla_policy ethnl_header_policy[ETHTOOL_A_HEADER_FLAGS + 1]; extern const struct nla_policy ethnl_header_policy_stats[ETHTOOL_A_HEADER_FLAGS + 1]; extern const struct nla_policy ethnl_strset_get_policy[ETHTOOL_A_STRSET_COUNTS_ONLY + 1]; extern const struct nla_policy ethnl_linkinfo_get_policy[ETHTOOL_A_LINKINFO_HEADER + 1]; extern const struct nla_policy ethnl_linkinfo_set_policy[ETHTOOL_A_LINKINFO_TP_MDIX_CTRL + 1]; extern const struct nla_policy ethnl_linkmodes_get_policy[ETHTOOL_A_LINKMODES_HEADER + 1]; extern const struct nla_policy ethnl_linkmodes_set_policy[ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG + 1]; extern const struct nla_policy ethnl_linkstate_get_policy[ETHTOOL_A_LINKSTATE_HEADER + 1]; extern const struct nla_policy ethnl_debug_get_policy[ETHTOOL_A_DEBUG_HEADER + 1]; extern const struct nla_policy ethnl_debug_set_policy[ETHTOOL_A_DEBUG_MSGMASK + 1]; extern const struct nla_policy ethnl_wol_get_policy[ETHTOOL_A_WOL_HEADER + 1]; extern const struct nla_policy ethnl_wol_set_policy[ETHTOOL_A_WOL_SOPASS + 1]; extern const struct nla_policy ethnl_features_get_policy[ETHTOOL_A_FEATURES_HEADER + 1]; extern const struct nla_policy ethnl_features_set_policy[ETHTOOL_A_FEATURES_WANTED + 1]; extern const struct nla_policy ethnl_privflags_get_policy[ETHTOOL_A_PRIVFLAGS_HEADER + 1]; extern const struct nla_policy ethnl_privflags_set_policy[ETHTOOL_A_PRIVFLAGS_FLAGS + 1]; extern const struct nla_policy ethnl_rings_get_policy[ETHTOOL_A_RINGS_HEADER + 1]; extern const struct nla_policy ethnl_rings_set_policy[ETHTOOL_A_RINGS_TX + 1]; extern const struct nla_policy ethnl_channels_get_policy[ETHTOOL_A_CHANNELS_HEADER + 1]; extern const struct nla_policy ethnl_channels_set_policy[ETHTOOL_A_CHANNELS_COMBINED_COUNT + 1]; extern const struct nla_policy ethnl_coalesce_get_policy[ETHTOOL_A_COALESCE_HEADER + 1]; extern const struct nla_policy ethnl_coalesce_set_policy[ETHTOOL_A_COALESCE_RATE_SAMPLE_INTERVAL + 1]; extern const struct nla_policy ethnl_pause_get_policy[ETHTOOL_A_PAUSE_HEADER + 1]; extern const struct nla_policy ethnl_pause_set_policy[ETHTOOL_A_PAUSE_TX + 1]; extern const struct nla_policy ethnl_eee_get_policy[ETHTOOL_A_EEE_HEADER + 1]; extern const struct nla_policy ethnl_eee_set_policy[ETHTOOL_A_EEE_TX_LPI_TIMER + 1]; extern const struct nla_policy ethnl_tsinfo_get_policy[ETHTOOL_A_TSINFO_HEADER + 1]; extern const struct nla_policy ethnl_cable_test_act_policy[ETHTOOL_A_CABLE_TEST_HEADER + 1]; extern const struct nla_policy ethnl_cable_test_tdr_act_policy[ETHTOOL_A_CABLE_TEST_TDR_CFG + 1]; extern const struct nla_policy ethnl_tunnel_info_get_policy[ETHTOOL_A_TUNNEL_INFO_HEADER + 1]; int ethnl_set_linkinfo(struct sk_buff *skb, struct genl_info *info); int ethnl_set_linkmodes(struct sk_buff *skb, struct genl_info *info); int ethnl_set_debug(struct sk_buff *skb, struct genl_info *info); int ethnl_set_wol(struct sk_buff *skb, struct genl_info *info); int ethnl_set_features(struct sk_buff *skb, struct genl_info *info); int ethnl_set_privflags(struct sk_buff *skb, struct genl_info *info); int ethnl_set_rings(struct sk_buff *skb, struct genl_info *info); int ethnl_set_channels(struct sk_buff *skb, struct genl_info *info); int ethnl_set_coalesce(struct sk_buff *skb, struct genl_info *info); int ethnl_set_pause(struct sk_buff *skb, struct genl_info *info); int ethnl_set_eee(struct sk_buff *skb, struct genl_info *info); int ethnl_act_cable_test(struct sk_buff *skb, struct genl_info *info); int ethnl_act_cable_test_tdr(struct sk_buff *skb, struct genl_info *info); int ethnl_tunnel_info_doit(struct sk_buff *skb, struct genl_info *info); int ethnl_tunnel_info_start(struct netlink_callback *cb); int ethnl_tunnel_info_dumpit(struct sk_buff *skb, struct netlink_callback *cb); #endif /* _NET_ETHTOOL_NETLINK_H */
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 /* SPDX-License-Identifier: GPL-2.0-only */ /* * net busy poll support * Copyright(c) 2013 Intel Corporation. * * Author: Eliezer Tamir * * Contact Information: * e1000-devel Mailing List <e1000-devel@lists.sourceforge.net> */ #ifndef _LINUX_NET_BUSY_POLL_H #define _LINUX_NET_BUSY_POLL_H #include <linux/netdevice.h> #include <linux/sched/clock.h> #include <linux/sched/signal.h> #include <net/ip.h> /* 0 - Reserved to indicate value not set * 1..NR_CPUS - Reserved for sender_cpu * NR_CPUS+1..~0 - Region available for NAPI IDs */ #define MIN_NAPI_ID ((unsigned int)(NR_CPUS + 1)) #ifdef CONFIG_NET_RX_BUSY_POLL struct napi_struct; extern unsigned int sysctl_net_busy_read __read_mostly; extern unsigned int sysctl_net_busy_poll __read_mostly; static inline bool net_busy_loop_on(void) { return sysctl_net_busy_poll; } static inline bool sk_can_busy_loop(const struct sock *sk) { return READ_ONCE(sk->sk_ll_usec) && !signal_pending(current); } bool sk_busy_loop_end(void *p, unsigned long start_time); void napi_busy_loop(unsigned int napi_id, bool (*loop_end)(void *, unsigned long), void *loop_end_arg); #else /* CONFIG_NET_RX_BUSY_POLL */ static inline unsigned long net_busy_loop_on(void) { return 0; } static inline bool sk_can_busy_loop(struct sock *sk) { return false; } #endif /* CONFIG_NET_RX_BUSY_POLL */ static inline unsigned long busy_loop_current_time(void) { #ifdef CONFIG_NET_RX_BUSY_POLL return (unsigned long)(local_clock() >> 10); #else return 0; #endif } /* in poll/select we use the global sysctl_net_ll_poll value */ static inline bool busy_loop_timeout(unsigned long start_time) { #ifdef CONFIG_NET_RX_BUSY_POLL unsigned long bp_usec = READ_ONCE(sysctl_net_busy_poll); if (bp_usec) { unsigned long end_time = start_time + bp_usec; unsigned long now = busy_loop_current_time(); return time_after(now, end_time); } #endif return true; } static inline bool sk_busy_loop_timeout(struct sock *sk, unsigned long start_time) { #ifdef CONFIG_NET_RX_BUSY_POLL unsigned long bp_usec = READ_ONCE(sk->sk_ll_usec); if (bp_usec) { unsigned long end_time = start_time + bp_usec; unsigned long now = busy_loop_current_time(); return time_after(now, end_time); } #endif return true; } static inline void sk_busy_loop(struct sock *sk, int nonblock) { #ifdef CONFIG_NET_RX_BUSY_POLL unsigned int napi_id = READ_ONCE(sk->sk_napi_id); if (napi_id >= MIN_NAPI_ID) napi_busy_loop(napi_id, nonblock ? NULL : sk_busy_loop_end, sk); #endif } /* used in the NIC receive handler to mark the skb */ static inline void skb_mark_napi_id(struct sk_buff *skb, struct napi_struct *napi) { #ifdef CONFIG_NET_RX_BUSY_POLL /* If the skb was already marked with a valid NAPI ID, avoid overwriting * it. */ if (skb->napi_id < MIN_NAPI_ID) skb->napi_id = napi->napi_id; #endif } /* used in the protocol hanlder to propagate the napi_id to the socket */ static inline void sk_mark_napi_id(struct sock *sk, const struct sk_buff *skb) { #ifdef CONFIG_NET_RX_BUSY_POLL WRITE_ONCE(sk->sk_napi_id, skb->napi_id); #endif sk_rx_queue_set(sk, skb); } /* variant used for unconnected sockets */ static inline void sk_mark_napi_id_once(struct sock *sk, const struct sk_buff *skb) { #ifdef CONFIG_NET_RX_BUSY_POLL if (!READ_ONCE(sk->sk_napi_id)) WRITE_ONCE(sk->sk_napi_id, skb->napi_id); #endif } #endif /* _LINUX_NET_BUSY_POLL_H */
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 /* SPDX-License-Identifier: GPL-2.0-only */ /* * Fast and scalable bitmaps. * * Copyright (C) 2016 Facebook * Copyright (C) 2013-2014 Jens Axboe */ #ifndef __LINUX_SCALE_BITMAP_H #define __LINUX_SCALE_BITMAP_H #include <linux/kernel.h> #include <linux/slab.h> struct seq_file; /** * struct sbitmap_word - Word in a &struct sbitmap. */ struct sbitmap_word { /** * @depth: Number of bits being used in @word/@cleared */ unsigned long depth; /** * @word: word holding free bits */ unsigned long word ____cacheline_aligned_in_smp; /** * @cleared: word holding cleared bits */ unsigned long cleared ____cacheline_aligned_in_smp; /** * @swap_lock: Held while swapping word <-> cleared */ spinlock_t swap_lock; } ____cacheline_aligned_in_smp; /** * struct sbitmap - Scalable bitmap. * * A &struct sbitmap is spread over multiple cachelines to avoid ping-pong. This * trades off higher memory usage for better scalability. */ struct sbitmap { /** * @depth: Number of bits used in the whole bitmap. */ unsigned int depth; /** * @shift: log2(number of bits used per word) */ unsigned int shift; /** * @map_nr: Number of words (cachelines) being used for the bitmap. */ unsigned int map_nr; /** * @map: Allocated bitmap. */ struct sbitmap_word *map; }; #define SBQ_WAIT_QUEUES 8 #define SBQ_WAKE_BATCH 8 /** * struct sbq_wait_state - Wait queue in a &struct sbitmap_queue. */ struct sbq_wait_state { /** * @wait_cnt: Number of frees remaining before we wake up. */ atomic_t wait_cnt; /** * @wait: Wait queue. */ wait_queue_head_t wait; } ____cacheline_aligned_in_smp; /** * struct sbitmap_queue - Scalable bitmap with the added ability to wait on free * bits. * * A &struct sbitmap_queue uses multiple wait queues and rolling wakeups to * avoid contention on the wait queue spinlock. This ensures that we don't hit a * scalability wall when we run out of free bits and have to start putting tasks * to sleep. */ struct sbitmap_queue { /** * @sb: Scalable bitmap. */ struct sbitmap sb; /* * @alloc_hint: Cache of last successfully allocated or freed bit. * * This is per-cpu, which allows multiple users to stick to different * cachelines until the map is exhausted. */ unsigned int __percpu *alloc_hint; /** * @wake_batch: Number of bits which must be freed before we wake up any * waiters. */ unsigned int wake_batch; /** * @wake_index: Next wait queue in @ws to wake up. */ atomic_t wake_index; /** * @ws: Wait queues. */ struct sbq_wait_state *ws; /* * @ws_active: count of currently active ws waitqueues */ atomic_t ws_active; /** * @round_robin: Allocate bits in strict round-robin order. */ bool round_robin; /** * @min_shallow_depth: The minimum shallow depth which may be passed to * sbitmap_queue_get_shallow() or __sbitmap_queue_get_shallow(). */ unsigned int min_shallow_depth; }; /** * sbitmap_init_node() - Initialize a &struct sbitmap on a specific memory node. * @sb: Bitmap to initialize. * @depth: Number of bits to allocate. * @shift: Use 2^@shift bits per word in the bitmap; if a negative number if * given, a good default is chosen. * @flags: Allocation flags. * @node: Memory node to allocate on. * * Return: Zero on success or negative errno on failure. */ int sbitmap_init_node(struct sbitmap *sb, unsigned int depth, int shift, gfp_t flags, int node); /** * sbitmap_free() - Free memory used by a &struct sbitmap. * @sb: Bitmap to free. */ static inline void sbitmap_free(struct sbitmap *sb) { kfree(sb->map); sb->map = NULL; } /** * sbitmap_resize() - Resize a &struct sbitmap. * @sb: Bitmap to resize. * @depth: New number of bits to resize to. * * Doesn't reallocate anything. It's up to the caller to ensure that the new * depth doesn't exceed the depth that the sb was initialized with. */ void sbitmap_resize(struct sbitmap *sb, unsigned int depth); /** * sbitmap_get() - Try to allocate a free bit from a &struct sbitmap. * @sb: Bitmap to allocate from. * @alloc_hint: Hint for where to start searching for a free bit. * @round_robin: If true, be stricter about allocation order; always allocate * starting from the last allocated bit. This is less efficient * than the default behavior (false). * * This operation provides acquire barrier semantics if it succeeds. * * Return: Non-negative allocated bit number if successful, -1 otherwise. */ int sbitmap_get(struct sbitmap *sb, unsigned int alloc_hint, bool round_robin); /** * sbitmap_get_shallow() - Try to allocate a free bit from a &struct sbitmap, * limiting the depth used from each word. * @sb: Bitmap to allocate from. * @alloc_hint: Hint for where to start searching for a free bit. * @shallow_depth: The maximum number of bits to allocate from a single word. * * This rather specific operation allows for having multiple users with * different allocation limits. E.g., there can be a high-priority class that * uses sbitmap_get() and a low-priority class that uses sbitmap_get_shallow() * with a @shallow_depth of (1 << (@sb->shift - 1)). Then, the low-priority * class can only allocate half of the total bits in the bitmap, preventing it * from starving out the high-priority class. * * Return: Non-negative allocated bit number if successful, -1 otherwise. */ int sbitmap_get_shallow(struct sbitmap *sb, unsigned int alloc_hint, unsigned long shallow_depth); /** * sbitmap_any_bit_set() - Check for a set bit in a &struct sbitmap. * @sb: Bitmap to check. * * Return: true if any bit in the bitmap is set, false otherwise. */ bool sbitmap_any_bit_set(const struct sbitmap *sb); #define SB_NR_TO_INDEX(sb, bitnr) ((bitnr) >> (sb)->shift) #define SB_NR_TO_BIT(sb, bitnr) ((bitnr) & ((1U << (sb)->shift) - 1U)) typedef bool (*sb_for_each_fn)(struct sbitmap *, unsigned int, void *); /** * __sbitmap_for_each_set() - Iterate over each set bit in a &struct sbitmap. * @start: Where to start the iteration. * @sb: Bitmap to iterate over. * @fn: Callback. Should return true to continue or false to break early. * @data: Pointer to pass to callback. * * This is inline even though it's non-trivial so that the function calls to the * callback will hopefully get optimized away. */ static inline void __sbitmap_for_each_set(struct sbitmap *sb, unsigned int start, sb_for_each_fn fn, void *data) { unsigned int index; unsigned int nr; unsigned int scanned = 0; if (start >= sb->depth) start = 0; index = SB_NR_TO_INDEX(sb, start); nr = SB_NR_TO_BIT(sb, start); while (scanned < sb->depth) { unsigned long word; unsigned int depth = min_t(unsigned int, sb->map[index].depth - nr, sb->depth - scanned); scanned += depth; word = sb->map[index].word & ~sb->map[index].cleared; if (!word) goto next; /* * On the first iteration of the outer loop, we need to add the * bit offset back to the size of the word for find_next_bit(). * On all other iterations, nr is zero, so this is a noop. */ depth += nr; while (1) { nr = find_next_bit(&word, depth, nr); if (nr >= depth) break; if (!fn(sb, (index << sb->shift) + nr, data)) return; nr++; } next: nr = 0; if (++index >= sb->map_nr) index = 0; } } /** * sbitmap_for_each_set() - Iterate over each set bit in a &struct sbitmap. * @sb: Bitmap to iterate over. * @fn: Callback. Should return true to continue or false to break early. * @data: Pointer to pass to callback. */ static inline void sbitmap_for_each_set(struct sbitmap *sb, sb_for_each_fn fn, void *data) { __sbitmap_for_each_set(sb, 0, fn, data); } static inline unsigned long *__sbitmap_word(struct sbitmap *sb, unsigned int bitnr) { return &sb->map[SB_NR_TO_INDEX(sb, bitnr)].word; } /* Helpers equivalent to the operations in asm/bitops.h and linux/bitmap.h */ static inline void sbitmap_set_bit(struct sbitmap *sb, unsigned int bitnr) { set_bit(SB_NR_TO_BIT(sb, bitnr), __sbitmap_word(sb, bitnr)); } static inline void sbitmap_clear_bit(struct sbitmap *sb, unsigned int bitnr) { clear_bit(SB_NR_TO_BIT(sb, bitnr), __sbitmap_word(sb, bitnr)); } /* * This one is special, since it doesn't actually clear the bit, rather it * sets the corresponding bit in the ->cleared mask instead. Paired with * the caller doing sbitmap_deferred_clear() if a given index is full, which * will clear the previously freed entries in the corresponding ->word. */ static inline void sbitmap_deferred_clear_bit(struct sbitmap *sb, unsigned int bitnr) { unsigned long *addr = &sb->map[SB_NR_TO_INDEX(sb, bitnr)].cleared; set_bit(SB_NR_TO_BIT(sb, bitnr), addr); } static inline void sbitmap_clear_bit_unlock(struct sbitmap *sb, unsigned int bitnr) { clear_bit_unlock(SB_NR_TO_BIT(sb, bitnr), __sbitmap_word(sb, bitnr)); } static inline int sbitmap_test_bit(struct sbitmap *sb, unsigned int bitnr) { return test_bit(SB_NR_TO_BIT(sb, bitnr), __sbitmap_word(sb, bitnr)); } /** * sbitmap_show() - Dump &struct sbitmap information to a &struct seq_file. * @sb: Bitmap to show. * @m: struct seq_file to write to. * * This is intended for debugging. The format may change at any time. */ void sbitmap_show(struct sbitmap *sb, struct seq_file *m); /** * sbitmap_bitmap_show() - Write a hex dump of a &struct sbitmap to a &struct * seq_file. * @sb: Bitmap to show. * @m: struct seq_file to write to. * * This is intended for debugging. The output isn't guaranteed to be internally * consistent. */ void sbitmap_bitmap_show(struct sbitmap *sb, struct seq_file *m); /** * sbitmap_queue_init_node() - Initialize a &struct sbitmap_queue on a specific * memory node. * @sbq: Bitmap queue to initialize. * @depth: See sbitmap_init_node(). * @shift: See sbitmap_init_node(). * @round_robin: See sbitmap_get(). * @flags: Allocation flags. * @node: Memory node to allocate on. * * Return: Zero on success or negative errno on failure. */ int sbitmap_queue_init_node(struct sbitmap_queue *sbq, unsigned int depth, int shift, bool round_robin, gfp_t flags, int node); /** * sbitmap_queue_free() - Free memory used by a &struct sbitmap_queue. * * @sbq: Bitmap queue to free. */ static inline void sbitmap_queue_free(struct sbitmap_queue *sbq) { kfree(sbq->ws); free_percpu(sbq->alloc_hint); sbitmap_free(&sbq->sb); } /** * sbitmap_queue_resize() - Resize a &struct sbitmap_queue. * @sbq: Bitmap queue to resize. * @depth: New number of bits to resize to. * * Like sbitmap_resize(), this doesn't reallocate anything. It has to do * some extra work on the &struct sbitmap_queue, so it's not safe to just * resize the underlying &struct sbitmap. */ void sbitmap_queue_resize(struct sbitmap_queue *sbq, unsigned int depth); /** * __sbitmap_queue_get() - Try to allocate a free bit from a &struct * sbitmap_queue with preemption already disabled. * @sbq: Bitmap queue to allocate from. * * Return: Non-negative allocated bit number if successful, -1 otherwise. */ int __sbitmap_queue_get(struct sbitmap_queue *sbq); /** * __sbitmap_queue_get_shallow() - Try to allocate a free bit from a &struct * sbitmap_queue, limiting the depth used from each word, with preemption * already disabled. * @sbq: Bitmap queue to allocate from. * @shallow_depth: The maximum number of bits to allocate from a single word. * See sbitmap_get_shallow(). * * If you call this, make sure to call sbitmap_queue_min_shallow_depth() after * initializing @sbq. * * Return: Non-negative allocated bit number if successful, -1 otherwise. */ int __sbitmap_queue_get_shallow(struct sbitmap_queue *sbq, unsigned int shallow_depth); /** * sbitmap_queue_get() - Try to allocate a free bit from a &struct * sbitmap_queue. * @sbq: Bitmap queue to allocate from. * @cpu: Output parameter; will contain the CPU we ran on (e.g., to be passed to * sbitmap_queue_clear()). * * Return: Non-negative allocated bit number if successful, -1 otherwise. */ static inline int sbitmap_queue_get(struct sbitmap_queue *sbq, unsigned int *cpu) { int nr; *cpu = get_cpu(); nr = __sbitmap_queue_get(sbq); put_cpu(); return nr; } /** * sbitmap_queue_get_shallow() - Try to allocate a free bit from a &struct * sbitmap_queue, limiting the depth used from each word. * @sbq: Bitmap queue to allocate from. * @cpu: Output parameter; will contain the CPU we ran on (e.g., to be passed to * sbitmap_queue_clear()). * @shallow_depth: The maximum number of bits to allocate from a single word. * See sbitmap_get_shallow(). * * If you call this, make sure to call sbitmap_queue_min_shallow_depth() after * initializing @sbq. * * Return: Non-negative allocated bit number if successful, -1 otherwise. */ static inline int sbitmap_queue_get_shallow(struct sbitmap_queue *sbq, unsigned int *cpu, unsigned int shallow_depth) { int nr; *cpu = get_cpu(); nr = __sbitmap_queue_get_shallow(sbq, shallow_depth); put_cpu(); return nr; } /** * sbitmap_queue_min_shallow_depth() - Inform a &struct sbitmap_queue of the * minimum shallow depth that will be used. * @sbq: Bitmap queue in question. * @min_shallow_depth: The minimum shallow depth that will be passed to * sbitmap_queue_get_shallow() or __sbitmap_queue_get_shallow(). * * sbitmap_queue_clear() batches wakeups as an optimization. The batch size * depends on the depth of the bitmap. Since the shallow allocation functions * effectively operate with a different depth, the shallow depth must be taken * into account when calculating the batch size. This function must be called * with the minimum shallow depth that will be used. Failure to do so can result * in missed wakeups. */ void sbitmap_queue_min_shallow_depth(struct sbitmap_queue *sbq, unsigned int min_shallow_depth); /** * sbitmap_queue_clear() - Free an allocated bit and wake up waiters on a * &struct sbitmap_queue. * @sbq: Bitmap to free from. * @nr: Bit number to free. * @cpu: CPU the bit was allocated on. */ void sbitmap_queue_clear(struct sbitmap_queue *sbq, unsigned int nr, unsigned int cpu); static inline int sbq_index_inc(int index) { return (index + 1) & (SBQ_WAIT_QUEUES - 1); } static inline void sbq_index_atomic_inc(atomic_t *index) { int old = atomic_read(index); int new = sbq_index_inc(old); atomic_cmpxchg(index, old, new); } /** * sbq_wait_ptr() - Get the next wait queue to use for a &struct * sbitmap_queue. * @sbq: Bitmap queue to wait on. * @wait_index: A counter per "user" of @sbq. */ static inline struct sbq_wait_state *sbq_wait_ptr(struct sbitmap_queue *sbq, atomic_t *wait_index) { struct sbq_wait_state *ws; ws = &sbq->ws[atomic_read(wait_index)]; sbq_index_atomic_inc(wait_index); return ws; } /** * sbitmap_queue_wake_all() - Wake up everything waiting on a &struct * sbitmap_queue. * @sbq: Bitmap queue to wake up. */ void sbitmap_queue_wake_all(struct sbitmap_queue *sbq); /** * sbitmap_queue_wake_up() - Wake up some of waiters in one waitqueue * on a &struct sbitmap_queue. * @sbq: Bitmap queue to wake up. */ void sbitmap_queue_wake_up(struct sbitmap_queue *sbq); /** * sbitmap_queue_show() - Dump &struct sbitmap_queue information to a &struct * seq_file. * @sbq: Bitmap queue to show. * @m: struct seq_file to write to. * * This is intended for debugging. The format may change at any time. */ void sbitmap_queue_show(struct sbitmap_queue *sbq, struct seq_file *m); struct sbq_wait { struct sbitmap_queue *sbq; /* if set, sbq_wait is accounted */ struct wait_queue_entry wait; }; #define DEFINE_SBQ_WAIT(name) \ struct sbq_wait name = { \ .sbq = NULL, \ .wait = { \ .private = current, \ .func = autoremove_wake_function, \ .entry = LIST_HEAD_INIT((name).wait.entry), \ } \ } /* * Wrapper around prepare_to_wait_exclusive(), which maintains some extra * internal state. */ void sbitmap_prepare_to_wait(struct sbitmap_queue *sbq, struct sbq_wait_state *ws, struct sbq_wait *sbq_wait, int state); /* * Must be paired with sbitmap_prepare_to_wait(). */ void sbitmap_finish_wait(struct sbitmap_queue *sbq, struct sbq_wait_state *ws, struct sbq_wait *sbq_wait); /* * Wrapper around add_wait_queue(), which maintains some extra internal state */ void sbitmap_add_wait_queue(struct sbitmap_queue *sbq, struct sbq_wait_state *ws, struct sbq_wait *sbq_wait); /* * Must be paired with sbitmap_add_wait_queue() */ void sbitmap_del_wait_queue(struct sbq_wait *sbq_wait); #endif /* __LINUX_SCALE_BITMAP_H */
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 /* SPDX-License-Identifier: GPL-2.0 */ /* * Because linux/module.h has tracepoints in the header, and ftrace.h * used to include this file, define_trace.h includes linux/module.h * But we do not want the module.h to override the TRACE_SYSTEM macro * variable that define_trace.h is processing, so we only set it * when module events are being processed, which would happen when * CREATE_TRACE_POINTS is defined. */ #ifdef CREATE_TRACE_POINTS #undef TRACE_SYSTEM #define TRACE_SYSTEM module #endif #if !defined(_TRACE_MODULE_H) || defined(TRACE_HEADER_MULTI_READ) #define _TRACE_MODULE_H #include <linux/tracepoint.h> #ifdef CONFIG_MODULES struct module; #define show_module_flags(flags) __print_flags(flags, "", \ { (1UL << TAINT_PROPRIETARY_MODULE), "P" }, \ { (1UL << TAINT_OOT_MODULE), "O" }, \ { (1UL << TAINT_FORCED_MODULE), "F" }, \ { (1UL << TAINT_CRAP), "C" }, \ { (1UL << TAINT_UNSIGNED_MODULE), "E" }) TRACE_EVENT(module_load, TP_PROTO(struct module *mod), TP_ARGS(mod), TP_STRUCT__entry( __field( unsigned int, taints ) __string( name, mod->name ) ), TP_fast_assign( __entry->taints = mod->taints; __assign_str(name, mod->name); ), TP_printk("%s %s", __get_str(name), show_module_flags(__entry->taints)) ); TRACE_EVENT(module_free, TP_PROTO(struct module *mod), TP_ARGS(mod), TP_STRUCT__entry( __string( name, mod->name ) ), TP_fast_assign( __assign_str(name, mod->name); ), TP_printk("%s", __get_str(name)) ); #ifdef CONFIG_MODULE_UNLOAD /* trace_module_get/put are only used if CONFIG_MODULE_UNLOAD is defined */ DECLARE_EVENT_CLASS(module_refcnt, TP_PROTO(struct module *mod, unsigned long ip), TP_ARGS(mod, ip), TP_STRUCT__entry( __field( unsigned long, ip ) __field( int, refcnt ) __string( name, mod->name ) ), TP_fast_assign( __entry->ip = ip; __entry->refcnt = atomic_read(&mod->refcnt); __assign_str(name, mod->name); ), TP_printk("%s call_site=%ps refcnt=%d", __get_str(name), (void *)__entry->ip, __entry->refcnt) ); DEFINE_EVENT(module_refcnt, module_get, TP_PROTO(struct module *mod, unsigned long ip), TP_ARGS(mod, ip) ); DEFINE_EVENT(module_refcnt, module_put, TP_PROTO(struct module *mod, unsigned long ip), TP_ARGS(mod, ip) ); #endif /* CONFIG_MODULE_UNLOAD */ TRACE_EVENT(module_request, TP_PROTO(char *name, bool wait, unsigned long ip), TP_ARGS(name, wait, ip), TP_STRUCT__entry( __field( unsigned long, ip ) __field( bool, wait ) __string( name, name ) ), TP_fast_assign( __entry->ip = ip; __entry->wait = wait; __assign_str(name, name); ), TP_printk("%s wait=%d call_site=%ps", __get_str(name), (int)__entry->wait, (void *)__entry->ip) ); #endif /* CONFIG_MODULES */ #endif /* _TRACE_MODULE_H */ /* This part must be outside protection */ #include <trace/define_trace.h>
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 /* SPDX-License-Identifier: GPL-2.0 */ /* * Block data types and constants. Directly include this file only to * break include dependency loop. */ #ifndef __LINUX_BLK_TYPES_H #define __LINUX_BLK_TYPES_H #include <linux/types.h> #include <linux/bvec.h> #include <linux/ktime.h> struct bio_set; struct bio; struct bio_integrity_payload; struct page; struct io_context; struct cgroup_subsys_state; typedef void (bio_end_io_t) (struct bio *); struct bio_crypt_ctx; struct block_device { dev_t bd_dev; int bd_openers; struct inode * bd_inode; /* will die */ struct super_block * bd_super; struct mutex bd_mutex; /* open/close mutex */ void * bd_claiming; void * bd_holder; int bd_holders; bool bd_write_holder; #ifdef CONFIG_SYSFS struct list_head bd_holder_disks; #endif struct block_device * bd_contains; u8 bd_partno; struct hd_struct * bd_part; /* number of times partitions within this device have been opened. */ unsigned bd_part_count; spinlock_t bd_size_lock; /* for bd_inode->i_size updates */ struct gendisk * bd_disk; struct backing_dev_info *bd_bdi; /* The counter of freeze processes */ int bd_fsfreeze_count; /* Mutex for freeze */ struct mutex bd_fsfreeze_mutex; } __randomize_layout; /* * Block error status values. See block/blk-core:blk_errors for the details. * Alpha cannot write a byte atomically, so we need to use 32-bit value. */ #if defined(CONFIG_ALPHA) && !defined(__alpha_bwx__) typedef u32 __bitwise blk_status_t; #else typedef u8 __bitwise blk_status_t; #endif #define BLK_STS_OK 0 #define BLK_STS_NOTSUPP ((__force blk_status_t)1) #define BLK_STS_TIMEOUT ((__force blk_status_t)2) #define BLK_STS_NOSPC ((__force blk_status_t)3) #define BLK_STS_TRANSPORT ((__force blk_status_t)4) #define BLK_STS_TARGET ((__force blk_status_t)5) #define BLK_STS_NEXUS ((__force blk_status_t)6) #define BLK_STS_MEDIUM ((__force blk_status_t)7) #define BLK_STS_PROTECTION ((__force blk_status_t)8) #define BLK_STS_RESOURCE ((__force blk_status_t)9) #define BLK_STS_IOERR ((__force blk_status_t)10) /* hack for device mapper, don't use elsewhere: */ #define BLK_STS_DM_REQUEUE ((__force blk_status_t)11) #define BLK_STS_AGAIN ((__force blk_status_t)12) /* * BLK_STS_DEV_RESOURCE is returned from the driver to the block layer if * device related resources are unavailable, but the driver can guarantee * that the queue will be rerun in the future once resources become * available again. This is typically the case for device specific * resources that are consumed for IO. If the driver fails allocating these * resources, we know that inflight (or pending) IO will free these * resource upon completion. * * This is different from BLK_STS_RESOURCE in that it explicitly references * a device specific resource. For resources of wider scope, allocation * failure can happen without having pending IO. This means that we can't * rely on request completions freeing these resources, as IO may not be in * flight. Examples of that are kernel memory allocations, DMA mappings, or * any other system wide resources. */ #define BLK_STS_DEV_RESOURCE ((__force blk_status_t)13) /* * BLK_STS_ZONE_RESOURCE is returned from the driver to the block layer if zone * related resources are unavailable, but the driver can guarantee the queue * will be rerun in the future once the resources become available again. * * This is different from BLK_STS_DEV_RESOURCE in that it explicitly references * a zone specific resource and IO to a different zone on the same device could * still be served. Examples of that are zones that are write-locked, but a read * to the same zone could be served. */ #define BLK_STS_ZONE_RESOURCE ((__force blk_status_t)14) /* * BLK_STS_ZONE_OPEN_RESOURCE is returned from the driver in the completion * path if the device returns a status indicating that too many zone resources * are currently open. The same command should be successful if resubmitted * after the number of open zones decreases below the device's limits, which is * reported in the request_queue's max_open_zones. */ #define BLK_STS_ZONE_OPEN_RESOURCE ((__force blk_status_t)15) /* * BLK_STS_ZONE_ACTIVE_RESOURCE is returned from the driver in the completion * path if the device returns a status indicating that too many zone resources * are currently active. The same command should be successful if resubmitted * after the number of active zones decreases below the device's limits, which * is reported in the request_queue's max_active_zones. */ #define BLK_STS_ZONE_ACTIVE_RESOURCE ((__force blk_status_t)16) /** * blk_path_error - returns true if error may be path related * @error: status the request was completed with * * Description: * This classifies block error status into non-retryable errors and ones * that may be successful if retried on a failover path. * * Return: * %false - retrying failover path will not help * %true - may succeed if retried */ static inline bool blk_path_error(blk_status_t error) { switch (error) { case BLK_STS_NOTSUPP: case BLK_STS_NOSPC: case BLK_STS_TARGET: case BLK_STS_NEXUS: case BLK_STS_MEDIUM: case BLK_STS_PROTECTION: return false; } /* Anything else could be a path failure, so should be retried */ return true; } /* * From most significant bit: * 1 bit: reserved for other usage, see below * 12 bits: original size of bio * 51 bits: issue time of bio */ #define BIO_ISSUE_RES_BITS 1 #define BIO_ISSUE_SIZE_BITS 12 #define BIO_ISSUE_RES_SHIFT (64 - BIO_ISSUE_RES_BITS) #define BIO_ISSUE_SIZE_SHIFT (BIO_ISSUE_RES_SHIFT - BIO_ISSUE_SIZE_BITS) #define BIO_ISSUE_TIME_MASK ((1ULL << BIO_ISSUE_SIZE_SHIFT) - 1) #define BIO_ISSUE_SIZE_MASK \ (((1ULL << BIO_ISSUE_SIZE_BITS) - 1) << BIO_ISSUE_SIZE_SHIFT) #define BIO_ISSUE_RES_MASK (~((1ULL << BIO_ISSUE_RES_SHIFT) - 1)) /* Reserved bit for blk-throtl */ #define BIO_ISSUE_THROTL_SKIP_LATENCY (1ULL << 63) struct bio_issue { u64 value; }; static inline u64 __bio_issue_time(u64 time) { return time & BIO_ISSUE_TIME_MASK; } static inline u64 bio_issue_time(struct bio_issue *issue) { return __bio_issue_time(issue->value); } static inline sector_t bio_issue_size(struct bio_issue *issue) { return ((issue->value & BIO_ISSUE_SIZE_MASK) >> BIO_ISSUE_SIZE_SHIFT); } static inline void bio_issue_init(struct bio_issue *issue, sector_t size) { size &= (1ULL << BIO_ISSUE_SIZE_BITS) - 1; issue->value = ((issue->value & BIO_ISSUE_RES_MASK) | (ktime_get_ns() & BIO_ISSUE_TIME_MASK) | ((u64)size << BIO_ISSUE_SIZE_SHIFT)); } /* * main unit of I/O for the block layer and lower layers (ie drivers and * stacking drivers) */ struct bio { struct bio *bi_next; /* request queue link */ struct gendisk *bi_disk; unsigned int bi_opf; /* bottom bits req flags, * top bits REQ_OP. Use * accessors. */ unsigned short bi_flags; /* status, etc and bvec pool number */ unsigned short bi_ioprio; unsigned short bi_write_hint; blk_status_t bi_status; u8 bi_partno; atomic_t __bi_remaining; struct bvec_iter bi_iter; bio_end_io_t *bi_end_io; void *bi_private; #ifdef CONFIG_BLK_CGROUP /* * Represents the association of the css and request_queue for the bio. * If a bio goes direct to device, it will not have a blkg as it will * not have a request_queue associated with it. The reference is put * on release of the bio. */ struct blkcg_gq *bi_blkg; struct bio_issue bi_issue; #ifdef CONFIG_BLK_CGROUP_IOCOST u64 bi_iocost_cost; #endif #endif #ifdef CONFIG_BLK_INLINE_ENCRYPTION struct bio_crypt_ctx *bi_crypt_context; #endif union { #if defined(CONFIG_BLK_DEV_INTEGRITY) struct bio_integrity_payload *bi_integrity; /* data integrity */ #endif }; unsigned short bi_vcnt; /* how many bio_vec's */ /* * Everything starting with bi_max_vecs will be preserved by bio_reset() */ unsigned short bi_max_vecs; /* max bvl_vecs we can hold */ atomic_t __bi_cnt; /* pin count */ struct bio_vec *bi_io_vec; /* the actual vec list */ struct bio_set *bi_pool; /* * We can inline a number of vecs at the end of the bio, to avoid * double allocations for a small number of bio_vecs. This member * MUST obviously be kept at the very end of the bio. */ struct bio_vec bi_inline_vecs[]; }; #define BIO_RESET_BYTES offsetof(struct bio, bi_max_vecs) /* * bio flags */ enum { BIO_NO_PAGE_REF, /* don't put release vec pages */ BIO_CLONED, /* doesn't own data */ BIO_BOUNCED, /* bio is a bounce bio */ BIO_WORKINGSET, /* contains userspace workingset pages */ BIO_QUIET, /* Make BIO Quiet */ BIO_CHAIN, /* chained bio, ->bi_remaining in effect */ BIO_REFFED, /* bio has elevated ->bi_cnt */ BIO_THROTTLED, /* This bio has already been subjected to * throttling rules. Don't do it again. */ BIO_TRACE_COMPLETION, /* bio_endio() should trace the final completion * of this bio. */ BIO_CGROUP_ACCT, /* has been accounted to a cgroup */ BIO_TRACKED, /* set if bio goes through the rq_qos path */ BIO_FLAG_LAST }; /* See BVEC_POOL_OFFSET below before adding new flags */ /* * We support 6 different bvec pools, the last one is magic in that it * is backed by a mempool. */ #define BVEC_POOL_NR 6 #define BVEC_POOL_MAX (BVEC_POOL_NR - 1) /* * Top 3 bits of bio flags indicate the pool the bvecs came from. We add * 1 to the actual index so that 0 indicates that there are no bvecs to be * freed. */ #define BVEC_POOL_BITS (3) #define BVEC_POOL_OFFSET (16 - BVEC_POOL_BITS) #define BVEC_POOL_IDX(bio) ((bio)->bi_flags >> BVEC_POOL_OFFSET) #if (1<< BVEC_POOL_BITS) < (BVEC_POOL_NR+1) # error "BVEC_POOL_BITS is too small" #endif /* * Flags starting here get preserved by bio_reset() - this includes * only BVEC_POOL_IDX() */ #define BIO_RESET_BITS BVEC_POOL_OFFSET typedef __u32 __bitwise blk_mq_req_flags_t; /* * Operations and flags common to the bio and request structures. * We use 8 bits for encoding the operation, and the remaining 24 for flags. * * The least significant bit of the operation number indicates the data * transfer direction: * * - if the least significant bit is set transfers are TO the device * - if the least significant bit is not set transfers are FROM the device * * If a operation does not transfer data the least significant bit has no * meaning. */ #define REQ_OP_BITS 8 #define REQ_OP_MASK ((1 << REQ_OP_BITS) - 1) #define REQ_FLAG_BITS 24 enum req_opf { /* read sectors from the device */ REQ_OP_READ = 0, /* write sectors to the device */ REQ_OP_WRITE = 1, /* flush the volatile write cache */ REQ_OP_FLUSH = 2, /* discard sectors */ REQ_OP_DISCARD = 3, /* securely erase sectors */ REQ_OP_SECURE_ERASE = 5, /* write the same sector many times */ REQ_OP_WRITE_SAME = 7, /* write the zero filled sector many times */ REQ_OP_WRITE_ZEROES = 9, /* Open a zone */ REQ_OP_ZONE_OPEN = 10, /* Close a zone */ REQ_OP_ZONE_CLOSE = 11, /* Transition a zone to full */ REQ_OP_ZONE_FINISH = 12, /* write data at the current zone write pointer */ REQ_OP_ZONE_APPEND = 13, /* reset a zone write pointer */ REQ_OP_ZONE_RESET = 15, /* reset all the zone present on the device */ REQ_OP_ZONE_RESET_ALL = 17, /* SCSI passthrough using struct scsi_request */ REQ_OP_SCSI_IN = 32, REQ_OP_SCSI_OUT = 33, /* Driver private requests */ REQ_OP_DRV_IN = 34, REQ_OP_DRV_OUT = 35, REQ_OP_LAST, }; enum req_flag_bits { __REQ_FAILFAST_DEV = /* no driver retries of device errors */ REQ_OP_BITS, __REQ_FAILFAST_TRANSPORT, /* no driver retries of transport errors */ __REQ_FAILFAST_DRIVER, /* no driver retries of driver errors */ __REQ_SYNC, /* request is sync (sync write or read) */ __REQ_META, /* metadata io request */ __REQ_PRIO, /* boost priority in cfq */ __REQ_NOMERGE, /* don't touch this for merging */ __REQ_IDLE, /* anticipate more IO after this one */ __REQ_INTEGRITY, /* I/O includes block integrity payload */ __REQ_FUA, /* forced unit access */ __REQ_PREFLUSH, /* request for cache flush */ __REQ_RAHEAD, /* read ahead, can fail anytime */ __REQ_BACKGROUND, /* background IO */ __REQ_NOWAIT, /* Don't wait if request will block */ /* * When a shared kthread needs to issue a bio for a cgroup, doing * so synchronously can lead to priority inversions as the kthread * can be trapped waiting for that cgroup. CGROUP_PUNT flag makes * submit_bio() punt the actual issuing to a dedicated per-blkcg * work item to avoid such priority inversions. */ __REQ_CGROUP_PUNT, /* command specific flags for REQ_OP_WRITE_ZEROES: */ __REQ_NOUNMAP, /* do not free blocks when zeroing */ __REQ_HIPRI, /* for driver use */ __REQ_DRV, __REQ_SWAP, /* swapping request. */ __REQ_NR_BITS, /* stops here */ }; #define REQ_FAILFAST_DEV (1ULL << __REQ_FAILFAST_DEV) #define REQ_FAILFAST_TRANSPORT (1ULL << __REQ_FAILFAST_TRANSPORT) #define REQ_FAILFAST_DRIVER (1ULL << __REQ_FAILFAST_DRIVER) #define REQ_SYNC (1ULL << __REQ_SYNC) #define REQ_META (1ULL << __REQ_META) #define REQ_PRIO (1ULL << __REQ_PRIO) #define REQ_NOMERGE (1ULL << __REQ_NOMERGE) #define REQ_IDLE (1ULL << __REQ_IDLE) #define REQ_INTEGRITY (1ULL << __REQ_INTEGRITY) #define REQ_FUA (1ULL << __REQ_FUA) #define REQ_PREFLUSH (1ULL << __REQ_PREFLUSH) #define REQ_RAHEAD (1ULL << __REQ_RAHEAD) #define REQ_BACKGROUND (1ULL << __REQ_BACKGROUND) #define REQ_NOWAIT (1ULL << __REQ_NOWAIT) #define REQ_CGROUP_PUNT (1ULL << __REQ_CGROUP_PUNT) #define REQ_NOUNMAP (1ULL << __REQ_NOUNMAP) #define REQ_HIPRI (1ULL << __REQ_HIPRI) #define REQ_DRV (1ULL << __REQ_DRV) #define REQ_SWAP (1ULL << __REQ_SWAP) #define REQ_FAILFAST_MASK \ (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | REQ_FAILFAST_DRIVER) #define REQ_NOMERGE_FLAGS \ (REQ_NOMERGE | REQ_PREFLUSH | REQ_FUA) enum stat_group { STAT_READ, STAT_WRITE, STAT_DISCARD, STAT_FLUSH, NR_STAT_GROUPS }; #define bio_op(bio) \ ((bio)->bi_opf & REQ_OP_MASK) #define req_op(req) \ ((req)->cmd_flags & REQ_OP_MASK) /* obsolete, don't use in new code */ static inline void bio_set_op_attrs(struct bio *bio, unsigned op, unsigned op_flags) { bio->bi_opf = op | op_flags; } static inline bool op_is_write(unsigned int op) { return (op & 1); } /* * Check if the bio or request is one that needs special treatment in the * flush state machine. */ static inline bool op_is_flush(unsigned int op) { return op & (REQ_FUA | REQ_PREFLUSH); } /* * Reads are always treated as synchronous, as are requests with the FUA or * PREFLUSH flag. Other operations may be marked as synchronous using the * REQ_SYNC flag. */ static inline bool op_is_sync(unsigned int op) { return (op & REQ_OP_MASK) == REQ_OP_READ || (op & (REQ_SYNC | REQ_FUA | REQ_PREFLUSH)); } static inline bool op_is_discard(unsigned int op) { return (op & REQ_OP_MASK) == REQ_OP_DISCARD; } /* * Check if a bio or request operation is a zone management operation, with * the exception of REQ_OP_ZONE_RESET_ALL which is treated as a special case * due to its different handling in the block layer and device response in * case of command failure. */ static inline bool op_is_zone_mgmt(enum req_opf op) { switch (op & REQ_OP_MASK) { case REQ_OP_ZONE_RESET: case REQ_OP_ZONE_OPEN: case REQ_OP_ZONE_CLOSE: case REQ_OP_ZONE_FINISH: return true; default: return false; } } static inline int op_stat_group(unsigned int op) { if (op_is_discard(op)) return STAT_DISCARD; return op_is_write(op); } typedef unsigned int blk_qc_t; #define BLK_QC_T_NONE -1U #define BLK_QC_T_SHIFT 16 #define BLK_QC_T_INTERNAL (1U << 31) static inline bool blk_qc_t_valid(blk_qc_t cookie) { return cookie != BLK_QC_T_NONE; } static inline unsigned int blk_qc_t_to_queue_num(blk_qc_t cookie) { return (cookie & ~BLK_QC_T_INTERNAL) >> BLK_QC_T_SHIFT; } static inline unsigned int blk_qc_t_to_tag(blk_qc_t cookie) { return cookie & ((1u << BLK_QC_T_SHIFT) - 1); } static inline bool blk_qc_t_is_internal(blk_qc_t cookie) { return (cookie & BLK_QC_T_INTERNAL) != 0; } struct blk_rq_stat { u64 mean; u64 min; u64 max; u32 nr_samples; u64 batch; }; #endif /* __LINUX_BLK_TYPES_H */
1 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 // SPDX-License-Identifier: GPL-2.0-only #include <linux/fault-inject.h> #include <linux/fault-inject-usercopy.h> static struct { struct fault_attr attr; } fail_usercopy = { .attr = FAULT_ATTR_INITIALIZER, }; static int __init setup_fail_usercopy(char *str) { return setup_fault_attr(&fail_usercopy.attr, str); } __setup("fail_usercopy=", setup_fail_usercopy); #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS static int __init fail_usercopy_debugfs(void) { struct dentry *dir; dir = fault_create_debugfs_attr("fail_usercopy", NULL, &fail_usercopy.attr); if (IS_ERR(dir)) return PTR_ERR(dir); return 0; } late_initcall(fail_usercopy_debugfs); #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */ bool should_fail_usercopy(void) { return should_fail(&fail_usercopy.attr, 1); } EXPORT_SYMBOL_GPL(should_fail_usercopy);
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1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 // SPDX-License-Identifier: GPL-2.0-or-later /* Common capabilities, needed by capability.o. */ #include <linux/capability.h> #include <linux/audit.h> #include <linux/init.h> #include <linux/kernel.h> #include <linux/lsm_hooks.h> #include <linux/file.h> #include <linux/mm.h> #include <linux/mman.h> #include <linux/pagemap.h> #include <linux/swap.h> #include <linux/skbuff.h> #include <linux/netlink.h> #include <linux/ptrace.h> #include <linux/xattr.h> #include <linux/hugetlb.h> #include <linux/mount.h> #include <linux/sched.h> #include <linux/prctl.h> #include <linux/securebits.h> #include <linux/user_namespace.h> #include <linux/binfmts.h> #include <linux/personality.h> /* * If a non-root user executes a setuid-root binary in * !secure(SECURE_NOROOT) mode, then we raise capabilities. * However if fE is also set, then the intent is for only * the file capabilities to be applied, and the setuid-root * bit is left on either to change the uid (plausible) or * to get full privilege on a kernel without file capabilities * support. So in that case we do not raise capabilities. * * Warn if that happens, once per boot. */ static void warn_setuid_and_fcaps_mixed(const char *fname) { static int warned; if (!warned) { printk(KERN_INFO "warning: `%s' has both setuid-root and" " effective capabilities. Therefore not raising all" " capabilities.\n", fname); warned = 1; } } /** * cap_capable - Determine whether a task has a particular effective capability * @cred: The credentials to use * @ns: The user namespace in which we need the capability * @cap: The capability to check for * @opts: Bitmask of options defined in include/linux/security.h * * Determine whether the nominated task has the specified capability amongst * its effective set, returning 0 if it does, -ve if it does not. * * NOTE WELL: cap_has_capability() cannot be used like the kernel's capable() * and has_capability() functions. That is, it has the reverse semantics: * cap_has_capability() returns 0 when a task has a capability, but the * kernel's capable() and has_capability() returns 1 for this case. */ int cap_capable(const struct cred *cred, struct user_namespace *targ_ns, int cap, unsigned int opts) { struct user_namespace *ns = targ_ns; /* See if cred has the capability in the target user namespace * by examining the target user namespace and all of the target * user namespace's parents. */ for (;;) { /* Do we have the necessary capabilities? */ if (ns == cred->user_ns) return cap_raised(cred->cap_effective, cap) ? 0 : -EPERM; /* * If we're already at a lower level than we're looking for, * we're done searching. */ if (ns->level <= cred->user_ns->level) return -EPERM; /* * The owner of the user namespace in the parent of the * user namespace has all caps. */ if ((ns->parent == cred->user_ns) && uid_eq(ns->owner, cred->euid)) return 0; /* * If you have a capability in a parent user ns, then you have * it over all children user namespaces as well. */ ns = ns->parent; } /* We never get here */ } /** * cap_settime - Determine whether the current process may set the system clock * @ts: The time to set * @tz: The timezone to set * * Determine whether the current process may set the system clock and timezone * information, returning 0 if permission granted, -ve if denied. */ int cap_settime(const struct timespec64 *ts, const struct timezone *tz) { if (!capable(CAP_SYS_TIME)) return -EPERM; return 0; } /** * cap_ptrace_access_check - Determine whether the current process may access * another * @child: The process to be accessed * @mode: The mode of attachment. * * If we are in the same or an ancestor user_ns and have all the target * task's capabilities, then ptrace access is allowed. * If we have the ptrace capability to the target user_ns, then ptrace * access is allowed. * Else denied. * * Determine whether a process may access another, returning 0 if permission * granted, -ve if denied. */ int cap_ptrace_access_check(struct task_struct *child, unsigned int mode) { int ret = 0; const struct cred *cred, *child_cred; const kernel_cap_t *caller_caps; rcu_read_lock(); cred = current_cred(); child_cred = __task_cred(child); if (mode & PTRACE_MODE_FSCREDS) caller_caps = &cred->cap_effective; else caller_caps = &cred->cap_permitted; if (cred->user_ns == child_cred->user_ns && cap_issubset(child_cred->cap_permitted, *caller_caps)) goto out; if (ns_capable(child_cred->user_ns, CAP_SYS_PTRACE)) goto out; ret = -EPERM; out: rcu_read_unlock(); return ret; } /** * cap_ptrace_traceme - Determine whether another process may trace the current * @parent: The task proposed to be the tracer * * If parent is in the same or an ancestor user_ns and has all current's * capabilities, then ptrace access is allowed. * If parent has the ptrace capability to current's user_ns, then ptrace * access is allowed. * Else denied. * * Determine whether the nominated task is permitted to trace the current * process, returning 0 if permission is granted, -ve if denied. */ int cap_ptrace_traceme(struct task_struct *parent) { int ret = 0; const struct cred *cred, *child_cred; rcu_read_lock(); cred = __task_cred(parent); child_cred = current_cred(); if (cred->user_ns == child_cred->user_ns && cap_issubset(child_cred->cap_permitted, cred->cap_permitted)) goto out; if (has_ns_capability(parent, child_cred->user_ns, CAP_SYS_PTRACE)) goto out; ret = -EPERM; out: rcu_read_unlock(); return ret; } /** * cap_capget - Retrieve a task's capability sets * @target: The task from which to retrieve the capability sets * @effective: The place to record the effective set * @inheritable: The place to record the inheritable set * @permitted: The place to record the permitted set * * This function retrieves the capabilities of the nominated task and returns * them to the caller. */ int cap_capget(struct task_struct *target, kernel_cap_t *effective, kernel_cap_t *inheritable, kernel_cap_t *permitted) { const struct cred *cred; /* Derived from kernel/capability.c:sys_capget. */ rcu_read_lock(); cred = __task_cred(target); *effective = cred->cap_effective; *inheritable = cred->cap_inheritable; *permitted = cred->cap_permitted; rcu_read_unlock(); return 0; } /* * Determine whether the inheritable capabilities are limited to the old * permitted set. Returns 1 if they are limited, 0 if they are not. */ static inline int cap_inh_is_capped(void) { /* they are so limited unless the current task has the CAP_SETPCAP * capability */ if (cap_capable(current_cred(), current_cred()->user_ns, CAP_SETPCAP, CAP_OPT_NONE) == 0) return 0; return 1; } /** * cap_capset - Validate and apply proposed changes to current's capabilities * @new: The proposed new credentials; alterations should be made here * @old: The current task's current credentials * @effective: A pointer to the proposed new effective capabilities set * @inheritable: A pointer to the proposed new inheritable capabilities set * @permitted: A pointer to the proposed new permitted capabilities set * * This function validates and applies a proposed mass change to the current * process's capability sets. The changes are made to the proposed new * credentials, and assuming no error, will be committed by the caller of LSM. */ int cap_capset(struct cred *new, const struct cred *old, const kernel_cap_t *effective, const kernel_cap_t *inheritable, const kernel_cap_t *permitted) { if (cap_inh_is_capped() && !cap_issubset(*inheritable, cap_combine(old->cap_inheritable, old->cap_permitted))) /* incapable of using this inheritable set */ return -EPERM; if (!cap_issubset(*inheritable, cap_combine(old->cap_inheritable, old->cap_bset))) /* no new pI capabilities outside bounding set */ return -EPERM; /* verify restrictions on target's new Permitted set */ if (!cap_issubset(*permitted, old->cap_permitted)) return -EPERM; /* verify the _new_Effective_ is a subset of the _new_Permitted_ */ if (!cap_issubset(*effective, *permitted)) return -EPERM; new->cap_effective = *effective; new->cap_inheritable = *inheritable; new->cap_permitted = *permitted; /* * Mask off ambient bits that are no longer both permitted and * inheritable. */ new->cap_ambient = cap_intersect(new->cap_ambient, cap_intersect(*permitted, *inheritable)); if (WARN_ON(!cap_ambient_invariant_ok(new))) return -EINVAL; return 0; } /** * cap_inode_need_killpriv - Determine if inode change affects privileges * @dentry: The inode/dentry in being changed with change marked ATTR_KILL_PRIV * * Determine if an inode having a change applied that's marked ATTR_KILL_PRIV * affects the security markings on that inode, and if it is, should * inode_killpriv() be invoked or the change rejected. * * Returns 1 if security.capability has a value, meaning inode_killpriv() * is required, 0 otherwise, meaning inode_killpriv() is not required. */ int cap_inode_need_killpriv(struct dentry *dentry) { struct inode *inode = d_backing_inode(dentry); int error; error = __vfs_getxattr(dentry, inode, XATTR_NAME_CAPS, NULL, 0); return error > 0; } /** * cap_inode_killpriv - Erase the security markings on an inode * @dentry: The inode/dentry to alter * * Erase the privilege-enhancing security markings on an inode. * * Returns 0 if successful, -ve on error. */ int cap_inode_killpriv(struct dentry *dentry) { int error; error = __vfs_removexattr(dentry, XATTR_NAME_CAPS); if (error == -EOPNOTSUPP) error = 0; return error; } static bool rootid_owns_currentns(kuid_t kroot) { struct user_namespace *ns; if (!uid_valid(kroot)) return false; for (ns = current_user_ns(); ; ns = ns->parent) { if (from_kuid(ns, kroot) == 0) return true; if (ns == &init_user_ns) break; } return false; } static __u32 sansflags(__u32 m) { return m & ~VFS_CAP_FLAGS_EFFECTIVE; } static bool is_v2header(size_t size, const struct vfs_cap_data *cap) { if (size != XATTR_CAPS_SZ_2) return false; return sansflags(le32_to_cpu(cap->magic_etc)) == VFS_CAP_REVISION_2; } static bool is_v3header(size_t size, const struct vfs_cap_data *cap) { if (size != XATTR_CAPS_SZ_3) return false; return sansflags(le32_to_cpu(cap->magic_etc)) == VFS_CAP_REVISION_3; } /* * getsecurity: We are called for security.* before any attempt to read the * xattr from the inode itself. * * This gives us a chance to read the on-disk value and convert it. If we * return -EOPNOTSUPP, then vfs_getxattr() will call the i_op handler. * * Note we are not called by vfs_getxattr_alloc(), but that is only called * by the integrity subsystem, which really wants the unconverted values - * so that's good. */ int cap_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc) { int size, ret; kuid_t kroot; u32 nsmagic, magic; uid_t root, mappedroot; char *tmpbuf = NULL; struct vfs_cap_data *cap; struct vfs_ns_cap_data *nscap = NULL; struct dentry *dentry; struct user_namespace *fs_ns; if (strcmp(name, "capability") != 0) return -EOPNOTSUPP; dentry = d_find_any_alias(inode); if (!dentry) return -EINVAL; size = sizeof(struct vfs_ns_cap_data); ret = (int) vfs_getxattr_alloc(dentry, XATTR_NAME_CAPS, &tmpbuf, size, GFP_NOFS); dput(dentry); if (ret < 0 || !tmpbuf) return ret; fs_ns = inode->i_sb->s_user_ns; cap = (struct vfs_cap_data *) tmpbuf; if (is_v2header((size_t) ret, cap)) { root = 0; } else if (is_v3header((size_t) ret, cap)) { nscap = (struct vfs_ns_cap_data *) tmpbuf; root = le32_to_cpu(nscap->rootid); } else { size = -EINVAL; goto out_free; } kroot = make_kuid(fs_ns, root); /* If the root kuid maps to a valid uid in current ns, then return * this as a nscap. */ mappedroot = from_kuid(current_user_ns(), kroot); if (mappedroot != (uid_t)-1 && mappedroot != (uid_t)0) { size = sizeof(struct vfs_ns_cap_data); if (alloc) { if (!nscap) { /* v2 -> v3 conversion */ nscap = kzalloc(size, GFP_ATOMIC); if (!nscap) { size = -ENOMEM; goto out_free; } nsmagic = VFS_CAP_REVISION_3; magic = le32_to_cpu(cap->magic_etc); if (magic & VFS_CAP_FLAGS_EFFECTIVE) nsmagic |= VFS_CAP_FLAGS_EFFECTIVE; memcpy(&nscap->data, &cap->data, sizeof(__le32) * 2 * VFS_CAP_U32); nscap->magic_etc = cpu_to_le32(nsmagic); } else { /* use allocated v3 buffer */ tmpbuf = NULL; } nscap->rootid = cpu_to_le32(mappedroot); *buffer = nscap; } goto out_free; } if (!rootid_owns_currentns(kroot)) { size = -EOVERFLOW; goto out_free; } /* This comes from a parent namespace. Return as a v2 capability */ size = sizeof(struct vfs_cap_data); if (alloc) { if (nscap) { /* v3 -> v2 conversion */ cap = kzalloc(size, GFP_ATOMIC); if (!cap) { size = -ENOMEM; goto out_free; } magic = VFS_CAP_REVISION_2; nsmagic = le32_to_cpu(nscap->magic_etc); if (nsmagic & VFS_CAP_FLAGS_EFFECTIVE) magic |= VFS_CAP_FLAGS_EFFECTIVE; memcpy(&cap->data, &nscap->data, sizeof(__le32) * 2 * VFS_CAP_U32); cap->magic_etc = cpu_to_le32(magic); } else { /* use unconverted v2 */ tmpbuf = NULL; } *buffer = cap; } out_free: kfree(tmpbuf); return size; } static kuid_t rootid_from_xattr(const void *value, size_t size, struct user_namespace *task_ns) { const struct vfs_ns_cap_data *nscap = value; uid_t rootid = 0; if (size == XATTR_CAPS_SZ_3) rootid = le32_to_cpu(nscap->rootid); return make_kuid(task_ns, rootid); } static bool validheader(size_t size, const struct vfs_cap_data *cap) { return is_v2header(size, cap) || is_v3header(size, cap); } /* * User requested a write of security.capability. If needed, update the * xattr to change from v2 to v3, or to fixup the v3 rootid. * * If all is ok, we return the new size, on error return < 0. */ int cap_convert_nscap(struct dentry *dentry, void **ivalue, size_t size) { struct vfs_ns_cap_data *nscap; uid_t nsrootid; const struct vfs_cap_data *cap = *ivalue; __u32 magic, nsmagic; struct inode *inode = d_backing_inode(dentry); struct user_namespace *task_ns = current_user_ns(), *fs_ns = inode->i_sb->s_user_ns; kuid_t rootid; size_t newsize; if (!*ivalue) return -EINVAL; if (!validheader(size, cap)) return -EINVAL; if (!capable_wrt_inode_uidgid(inode, CAP_SETFCAP)) return -EPERM; if (size == XATTR_CAPS_SZ_2) if (ns_capable(inode->i_sb->s_user_ns, CAP_SETFCAP)) /* user is privileged, just write the v2 */ return size; rootid = rootid_from_xattr(*ivalue, size, task_ns); if (!uid_valid(rootid)) return -EINVAL; nsrootid = from_kuid(fs_ns, rootid); if (nsrootid == -1) return -EINVAL; newsize = sizeof(struct vfs_ns_cap_data); nscap = kmalloc(newsize, GFP_ATOMIC); if (!nscap) return -ENOMEM; nscap->rootid = cpu_to_le32(nsrootid); nsmagic = VFS_CAP_REVISION_3; magic = le32_to_cpu(cap->magic_etc); if (magic & VFS_CAP_FLAGS_EFFECTIVE) nsmagic |= VFS_CAP_FLAGS_EFFECTIVE; nscap->magic_etc = cpu_to_le32(nsmagic); memcpy(&nscap->data, &cap->data, sizeof(__le32) * 2 * VFS_CAP_U32); kvfree(*ivalue); *ivalue = nscap; return newsize; } /* * Calculate the new process capability sets from the capability sets attached * to a file. */ static inline int bprm_caps_from_vfs_caps(struct cpu_vfs_cap_data *caps, struct linux_binprm *bprm, bool *effective, bool *has_fcap) { struct cred *new = bprm->cred; unsigned i; int ret = 0; if (caps->magic_etc & VFS_CAP_FLAGS_EFFECTIVE) *effective = true; if (caps->magic_etc & VFS_CAP_REVISION_MASK) *has_fcap = true; CAP_FOR_EACH_U32(i) { __u32 permitted = caps->permitted.cap[i]; __u32 inheritable = caps->inheritable.cap[i]; /* * pP' = (X & fP) | (pI & fI) * The addition of pA' is handled later. */ new->cap_permitted.cap[i] = (new->cap_bset.cap[i] & permitted) | (new->cap_inheritable.cap[i] & inheritable); if (permitted & ~new->cap_permitted.cap[i]) /* insufficient to execute correctly */ ret = -EPERM; } /* * For legacy apps, with no internal support for recognizing they * do not have enough capabilities, we return an error if they are * missing some "forced" (aka file-permitted) capabilities. */ return *effective ? ret : 0; } /* * Extract the on-exec-apply capability sets for an executable file. */ int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data *cpu_caps) { struct inode *inode = d_backing_inode(dentry); __u32 magic_etc; unsigned tocopy, i; int size; struct vfs_ns_cap_data data, *nscaps = &data; struct vfs_cap_data *caps = (struct vfs_cap_data *) &data; kuid_t rootkuid; struct user_namespace *fs_ns; memset(cpu_caps, 0, sizeof(struct cpu_vfs_cap_data)); if (!inode) return -ENODATA; fs_ns = inode->i_sb->s_user_ns; size = __vfs_getxattr((struct dentry *)dentry, inode, XATTR_NAME_CAPS, &data, XATTR_CAPS_SZ); if (size == -ENODATA || size == -EOPNOTSUPP) /* no data, that's ok */ return -ENODATA; if (size < 0) return size; if (size < sizeof(magic_etc)) return -EINVAL; cpu_caps->magic_etc = magic_etc = le32_to_cpu(caps->magic_etc); rootkuid = make_kuid(fs_ns, 0); switch (magic_etc & VFS_CAP_REVISION_MASK) { case VFS_CAP_REVISION_1: if (size != XATTR_CAPS_SZ_1) return -EINVAL; tocopy = VFS_CAP_U32_1; break; case VFS_CAP_REVISION_2: if (size != XATTR_CAPS_SZ_2) return -EINVAL; tocopy = VFS_CAP_U32_2; break; case VFS_CAP_REVISION_3: if (size != XATTR_CAPS_SZ_3) return -EINVAL; tocopy = VFS_CAP_U32_3; rootkuid = make_kuid(fs_ns, le32_to_cpu(nscaps->rootid)); break; default: return -EINVAL; } /* Limit the caps to the mounter of the filesystem * or the more limited uid specified in the xattr. */ if (!rootid_owns_currentns(rootkuid)) return -ENODATA; CAP_FOR_EACH_U32(i) { if (i >= tocopy) break; cpu_caps->permitted.cap[i] = le32_to_cpu(caps->data[i].permitted); cpu_caps->inheritable.cap[i] = le32_to_cpu(caps->data[i].inheritable); } cpu_caps->permitted.cap[CAP_LAST_U32] &= CAP_LAST_U32_VALID_MASK; cpu_caps->inheritable.cap[CAP_LAST_U32] &= CAP_LAST_U32_VALID_MASK; cpu_caps->rootid = rootkuid; return 0; } /* * Attempt to get the on-exec apply capability sets for an executable file from * its xattrs and, if present, apply them to the proposed credentials being * constructed by execve(). */ static int get_file_caps(struct linux_binprm *bprm, struct file *file, bool *effective, bool *has_fcap) { int rc = 0; struct cpu_vfs_cap_data vcaps; cap_clear(bprm->cred->cap_permitted); if (!file_caps_enabled) return 0; if (!mnt_may_suid(file->f_path.mnt)) return 0; /* * This check is redundant with mnt_may_suid() but is kept to make * explicit that capability bits are limited to s_user_ns and its * descendants. */ if (!current_in_userns(file->f_path.mnt->mnt_sb->s_user_ns)) return 0; rc = get_vfs_caps_from_disk(file->f_path.dentry, &vcaps); if (rc < 0) { if (rc == -EINVAL) printk(KERN_NOTICE "Invalid argument reading file caps for %s\n", bprm->filename); else if (rc == -ENODATA) rc = 0; goto out; } rc = bprm_caps_from_vfs_caps(&vcaps, bprm, effective, has_fcap); out: if (rc) cap_clear(bprm->cred->cap_permitted); return rc; } static inline bool root_privileged(void) { return !issecure(SECURE_NOROOT); } static inline bool __is_real(kuid_t uid, struct cred *cred) { return uid_eq(cred->uid, uid); } static inline bool __is_eff(kuid_t uid, struct cred *cred) { return uid_eq(cred->euid, uid); } static inline bool __is_suid(kuid_t uid, struct cred *cred) { return !__is_real(uid, cred) && __is_eff(uid, cred); } /* * handle_privileged_root - Handle case of privileged root * @bprm: The execution parameters, including the proposed creds * @has_fcap: Are any file capabilities set? * @effective: Do we have effective root privilege? * @root_uid: This namespace' root UID WRT initial USER namespace * * Handle the case where root is privileged and hasn't been neutered by * SECURE_NOROOT. If file capabilities are set, they won't be combined with * set UID root and nothing is changed. If we are root, cap_permitted is * updated. If we have become set UID root, the effective bit is set. */ static void handle_privileged_root(struct linux_binprm *bprm, bool has_fcap, bool *effective, kuid_t root_uid) { const struct cred *old = current_cred(); struct cred *new = bprm->cred; if (!root_privileged()) return; /* * If the legacy file capability is set, then don't set privs * for a setuid root binary run by a non-root user. Do set it * for a root user just to cause least surprise to an admin. */ if (has_fcap && __is_suid(root_uid, new)) { warn_setuid_and_fcaps_mixed(bprm->filename); return; } /* * To support inheritance of root-permissions and suid-root * executables under compatibility mode, we override the * capability sets for the file. */ if (__is_eff(root_uid, new) || __is_real(root_uid, new)) { /* pP' = (cap_bset & ~0) | (pI & ~0) */ new->cap_permitted = cap_combine(old->cap_bset, old->cap_inheritable); } /* * If only the real uid is 0, we do not set the effective bit. */ if (__is_eff(root_uid, new)) *effective = true; } #define __cap_gained(field, target, source) \ !cap_issubset(target->cap_##field, source->cap_##field) #define __cap_grew(target, source, cred) \ !cap_issubset(cred->cap_##target, cred->cap_##source) #define __cap_full(field, cred) \ cap_issubset(CAP_FULL_SET, cred->cap_##field) static inline bool __is_setuid(struct cred *new, const struct cred *old) { return !uid_eq(new->euid, old->uid); } static inline bool __is_setgid(struct cred *new, const struct cred *old) { return !gid_eq(new->egid, old->gid); } /* * 1) Audit candidate if current->cap_effective is set * * We do not bother to audit if 3 things are true: * 1) cap_effective has all caps * 2) we became root *OR* are were already root * 3) root is supposed to have all caps (SECURE_NOROOT) * Since this is just a normal root execing a process. * * Number 1 above might fail if you don't have a full bset, but I think * that is interesting information to audit. * * A number of other conditions require logging: * 2) something prevented setuid root getting all caps * 3) non-setuid root gets fcaps * 4) non-setuid root gets ambient */ static inline bool nonroot_raised_pE(struct cred *new, const struct cred *old, kuid_t root, bool has_fcap) { bool ret = false; if ((__cap_grew(effective, ambient, new) && !(__cap_full(effective, new) && (__is_eff(root, new) || __is_real(root, new)) && root_privileged())) || (root_privileged() && __is_suid(root, new) && !__cap_full(effective, new)) || (!__is_setuid(new, old) && ((has_fcap && __cap_gained(permitted, new, old)) || __cap_gained(ambient, new, old)))) ret = true; return ret; } /** * cap_bprm_creds_from_file - Set up the proposed credentials for execve(). * @bprm: The execution parameters, including the proposed creds * @file: The file to pull the credentials from * * Set up the proposed credentials for a new execution context being * constructed by execve(). The proposed creds in @bprm->cred is altered, * which won't take effect immediately. Returns 0 if successful, -ve on error. */ int cap_bprm_creds_from_file(struct linux_binprm *bprm, struct file *file) { /* Process setpcap binaries and capabilities for uid 0 */ const struct cred *old = current_cred(); struct cred *new = bprm->cred; bool effective = false, has_fcap = false, is_setid; int ret; kuid_t root_uid; if (WARN_ON(!cap_ambient_invariant_ok(old))) return -EPERM; ret = get_file_caps(bprm, file, &effective, &has_fcap); if (ret < 0) return ret; root_uid = make_kuid(new->user_ns, 0); handle_privileged_root(bprm, has_fcap, &effective, root_uid); /* if we have fs caps, clear dangerous personality flags */ if (__cap_gained(permitted, new, old)) bprm->per_clear |= PER_CLEAR_ON_SETID; /* Don't let someone trace a set[ug]id/setpcap binary with the revised * credentials unless they have the appropriate permit. * * In addition, if NO_NEW_PRIVS, then ensure we get no new privs. */ is_setid = __is_setuid(new, old) || __is_setgid(new, old); if ((is_setid || __cap_gained(permitted, new, old)) && ((bprm->unsafe & ~LSM_UNSAFE_PTRACE) || !ptracer_capable(current, new->user_ns))) { /* downgrade; they get no more than they had, and maybe less */ if (!ns_capable(new->user_ns, CAP_SETUID) || (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)) { new->euid = new->uid; new->egid = new->gid; } new->cap_permitted = cap_intersect(new->cap_permitted, old->cap_permitted); } new->suid = new->fsuid = new->euid; new->sgid = new->fsgid = new->egid; /* File caps or setid cancels ambient. */ if (has_fcap || is_setid) cap_clear(new->cap_ambient); /* * Now that we've computed pA', update pP' to give: * pP' = (X & fP) | (pI & fI) | pA' */ new->cap_permitted = cap_combine(new->cap_permitted, new->cap_ambient); /* * Set pE' = (fE ? pP' : pA'). Because pA' is zero if fE is set, * this is the same as pE' = (fE ? pP' : 0) | pA'. */ if (effective) new->cap_effective = new->cap_permitted; else new->cap_effective = new->cap_ambient; if (WARN_ON(!cap_ambient_invariant_ok(new))) return -EPERM; if (nonroot_raised_pE(new, old, root_uid, has_fcap)) { ret = audit_log_bprm_fcaps(bprm, new, old); if (ret < 0) return ret; } new->securebits &= ~issecure_mask(SECURE_KEEP_CAPS); if (WARN_ON(!cap_ambient_invariant_ok(new))) return -EPERM; /* Check for privilege-elevated exec. */ if (is_setid || (!__is_real(root_uid, new) && (effective || __cap_grew(permitted, ambient, new)))) bprm->secureexec = 1; return 0; } /** * cap_inode_setxattr - Determine whether an xattr may be altered * @dentry: The inode/dentry being altered * @name: The name of the xattr to be changed * @value: The value that the xattr will be changed to * @size: The size of value * @flags: The replacement flag * * Determine whether an xattr may be altered or set on an inode, returning 0 if * permission is granted, -ve if denied. * * This is used to make sure security xattrs don't get updated or set by those * who aren't privileged to do so. */ int cap_inode_setxattr(struct dentry *dentry, const char *name, const void *value, size_t size, int flags) { struct user_namespace *user_ns = dentry->d_sb->s_user_ns; /* Ignore non-security xattrs */ if (strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) != 0) return 0; /* * For XATTR_NAME_CAPS the check will be done in * cap_convert_nscap(), called by setxattr() */ if (strcmp(name, XATTR_NAME_CAPS) == 0) return 0; if (!ns_capable(user_ns, CAP_SYS_ADMIN)) return -EPERM; return 0; } /** * cap_inode_removexattr - Determine whether an xattr may be removed * @dentry: The inode/dentry being altered * @name: The name of the xattr to be changed * * Determine whether an xattr may be removed from an inode, returning 0 if * permission is granted, -ve if denied. * * This is used to make sure security xattrs don't get removed by those who * aren't privileged to remove them. */ int cap_inode_removexattr(struct dentry *dentry, const char *name) { struct user_namespace *user_ns = dentry->d_sb->s_user_ns; /* Ignore non-security xattrs */ if (strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) != 0) return 0; if (strcmp(name, XATTR_NAME_CAPS) == 0) { /* security.capability gets namespaced */ struct inode *inode = d_backing_inode(dentry); if (!inode) return -EINVAL; if (!capable_wrt_inode_uidgid(inode, CAP_SETFCAP)) return -EPERM; return 0; } if (!ns_capable(user_ns, CAP_SYS_ADMIN)) return -EPERM; return 0; } /* * cap_emulate_setxuid() fixes the effective / permitted capabilities of * a process after a call to setuid, setreuid, or setresuid. * * 1) When set*uiding _from_ one of {r,e,s}uid == 0 _to_ all of * {r,e,s}uid != 0, the permitted and effective capabilities are * cleared. * * 2) When set*uiding _from_ euid == 0 _to_ euid != 0, the effective * capabilities of the process are cleared. * * 3) When set*uiding _from_ euid != 0 _to_ euid == 0, the effective * capabilities are set to the permitted capabilities. * * fsuid is handled elsewhere. fsuid == 0 and {r,e,s}uid!= 0 should * never happen. * * -astor * * cevans - New behaviour, Oct '99 * A process may, via prctl(), elect to keep its capabilities when it * calls setuid() and switches away from uid==0. Both permitted and * effective sets will be retained. * Without this change, it was impossible for a daemon to drop only some * of its privilege. The call to setuid(!=0) would drop all privileges! * Keeping uid 0 is not an option because uid 0 owns too many vital * files.. * Thanks to Olaf Kirch and Peter Benie for spotting this. */ static inline void cap_emulate_setxuid(struct cred *new, const struct cred *old) { kuid_t root_uid = make_kuid(old->user_ns, 0); if ((uid_eq(old->uid, root_uid) || uid_eq(old->euid, root_uid) || uid_eq(old->suid, root_uid)) && (!uid_eq(new->uid, root_uid) && !uid_eq(new->euid, root_uid) && !uid_eq(new->suid, root_uid))) { if (!issecure(SECURE_KEEP_CAPS)) { cap_clear(new->cap_permitted); cap_clear(new->cap_effective); } /* * Pre-ambient programs expect setresuid to nonroot followed * by exec to drop capabilities. We should make sure that * this remains the case. */ cap_clear(new->cap_ambient); } if (uid_eq(old->euid, root_uid) && !uid_eq(new->euid, root_uid)) cap_clear(new->cap_effective); if (!uid_eq(old->euid, root_uid) && uid_eq(new->euid, root_uid)) new->cap_effective = new->cap_permitted; } /** * cap_task_fix_setuid - Fix up the results of setuid() call * @new: The proposed credentials * @old: The current task's current credentials * @flags: Indications of what has changed * * Fix up the results of setuid() call before the credential changes are * actually applied, returning 0 to grant the changes, -ve to deny them. */ int cap_task_fix_setuid(struct cred *new, const struct cred *old, int flags) { switch (flags) { case LSM_SETID_RE: case LSM_SETID_ID: case LSM_SETID_RES: /* juggle the capabilities to follow [RES]UID changes unless * otherwise suppressed */ if (!issecure(SECURE_NO_SETUID_FIXUP)) cap_emulate_setxuid(new, old); break; case LSM_SETID_FS: /* juggle the capabilties to follow FSUID changes, unless * otherwise suppressed * * FIXME - is fsuser used for all CAP_FS_MASK capabilities? * if not, we might be a bit too harsh here. */ if (!issecure(SECURE_NO_SETUID_FIXUP)) { kuid_t root_uid = make_kuid(old->user_ns, 0); if (uid_eq(old->fsuid, root_uid) && !uid_eq(new->fsuid, root_uid)) new->cap_effective = cap_drop_fs_set(new->cap_effective); if (!uid_eq(old->fsuid, root_uid) && uid_eq(new->fsuid, root_uid)) new->cap_effective = cap_raise_fs_set(new->cap_effective, new->cap_permitted); } break; default: return -EINVAL; } return 0; } /* * Rationale: code calling task_setscheduler, task_setioprio, and * task_setnice, assumes that * . if capable(cap_sys_nice), then those actions should be allowed * . if not capable(cap_sys_nice), but acting on your own processes, * then those actions should be allowed * This is insufficient now since you can call code without suid, but * yet with increased caps. * So we check for increased caps on the target process. */ static int cap_safe_nice(struct task_struct *p) { int is_subset, ret = 0; rcu_read_lock(); is_subset = cap_issubset(__task_cred(p)->cap_permitted, current_cred()->cap_permitted); if (!is_subset && !ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) ret = -EPERM; rcu_read_unlock(); return ret; } /** * cap_task_setscheduler - Detemine if scheduler policy change is permitted * @p: The task to affect * * Detemine if the requested scheduler policy change is permitted for the * specified task, returning 0 if permission is granted, -ve if denied. */ int cap_task_setscheduler(struct task_struct *p) { return cap_safe_nice(p); } /** * cap_task_ioprio - Detemine if I/O priority change is permitted * @p: The task to affect * @ioprio: The I/O priority to set * * Detemine if the requested I/O priority change is permitted for the specified * task, returning 0 if permission is granted, -ve if denied. */ int cap_task_setioprio(struct task_struct *p, int ioprio) { return cap_safe_nice(p); } /** * cap_task_ioprio - Detemine if task priority change is permitted * @p: The task to affect * @nice: The nice value to set * * Detemine if the requested task priority change is permitted for the * specified task, returning 0 if permission is granted, -ve if denied. */ int cap_task_setnice(struct task_struct *p, int nice) { return cap_safe_nice(p); } /* * Implement PR_CAPBSET_DROP. Attempt to remove the specified capability from * the current task's bounding set. Returns 0 on success, -ve on error. */ static int cap_prctl_drop(unsigned long cap) { struct cred *new; if (!ns_capable(current_user_ns(), CAP_SETPCAP)) return -EPERM; if (!cap_valid(cap)) return -EINVAL; new = prepare_creds(); if (!new) return -ENOMEM; cap_lower(new->cap_bset, cap); return commit_creds(new); } /** * cap_task_prctl - Implement process control functions for this security module * @option: The process control function requested * @arg2, @arg3, @arg4, @arg5: The argument data for this function * * Allow process control functions (sys_prctl()) to alter capabilities; may * also deny access to other functions not otherwise implemented here. * * Returns 0 or +ve on success, -ENOSYS if this function is not implemented * here, other -ve on error. If -ENOSYS is returned, sys_prctl() and other LSM * modules will consider performing the function. */ int cap_task_prctl(int option, unsigned long arg2, unsigned long arg3, unsigned long arg4, unsigned long arg5) { const struct cred *old = current_cred(); struct cred *new; switch (option) { case PR_CAPBSET_READ: if (!cap_valid(arg2)) return -EINVAL; return !!cap_raised(old->cap_bset, arg2); case PR_CAPBSET_DROP: return cap_prctl_drop(arg2); /* * The next four prctl's remain to assist with transitioning a * system from legacy UID=0 based privilege (when filesystem * capabilities are not in use) to a system using filesystem * capabilities only - as the POSIX.1e draft intended. * * Note: * * PR_SET_SECUREBITS = * issecure_mask(SECURE_KEEP_CAPS_LOCKED) * | issecure_mask(SECURE_NOROOT) * | issecure_mask(SECURE_NOROOT_LOCKED) * | issecure_mask(SECURE_NO_SETUID_FIXUP) * | issecure_mask(SECURE_NO_SETUID_FIXUP_LOCKED) * * will ensure that the current process and all of its * children will be locked into a pure * capability-based-privilege environment. */ case PR_SET_SECUREBITS: if ((((old->securebits & SECURE_ALL_LOCKS) >> 1) & (old->securebits ^ arg2)) /*[1]*/ || ((old->securebits & SECURE_ALL_LOCKS & ~arg2)) /*[2]*/ || (arg2 & ~(SECURE_ALL_LOCKS | SECURE_ALL_BITS)) /*[3]*/ || (cap_capable(current_cred(), current_cred()->user_ns, CAP_SETPCAP, CAP_OPT_NONE) != 0) /*[4]*/ /* * [1] no changing of bits that are locked * [2] no unlocking of locks * [3] no setting of unsupported bits * [4] doing anything requires privilege (go read about * the "sendmail capabilities bug") */ ) /* cannot change a locked bit */ return -EPERM; new = prepare_creds(); if (!new) return -ENOMEM; new->securebits = arg2; return commit_creds(new); case PR_GET_SECUREBITS: return old->securebits; case PR_GET_KEEPCAPS: return !!issecure(SECURE_KEEP_CAPS); case PR_SET_KEEPCAPS: if (arg2 > 1) /* Note, we rely on arg2 being unsigned here */ return -EINVAL; if (issecure(SECURE_KEEP_CAPS_LOCKED)) return -EPERM; new = prepare_creds(); if (!new) return -ENOMEM; if (arg2) new->securebits |= issecure_mask(SECURE_KEEP_CAPS); else new->securebits &= ~issecure_mask(SECURE_KEEP_CAPS); return commit_creds(new); case PR_CAP_AMBIENT: if (arg2 == PR_CAP_AMBIENT_CLEAR_ALL) { if (arg3 | arg4 | arg5) return -EINVAL; new = prepare_creds(); if (!new) return -ENOMEM; cap_clear(new->cap_ambient); return commit_creds(new); } if (((!cap_valid(arg3)) | arg4 | arg5)) return -EINVAL; if (arg2 == PR_CAP_AMBIENT_IS_SET) { return !!cap_raised(current_cred()->cap_ambient, arg3); } else if (arg2 != PR_CAP_AMBIENT_RAISE && arg2 != PR_CAP_AMBIENT_LOWER) { return -EINVAL; } else { if (arg2 == PR_CAP_AMBIENT_RAISE && (!cap_raised(current_cred()->cap_permitted, arg3) || !cap_raised(current_cred()->cap_inheritable, arg3) || issecure(SECURE_NO_CAP_AMBIENT_RAISE))) return -EPERM; new = prepare_creds(); if (!new) return -ENOMEM; if (arg2 == PR_CAP_AMBIENT_RAISE) cap_raise(new->cap_ambient, arg3); else cap_lower(new->cap_ambient, arg3); return commit_creds(new); } default: /* No functionality available - continue with default */ return -ENOSYS; } } /** * cap_vm_enough_memory - Determine whether a new virtual mapping is permitted * @mm: The VM space in which the new mapping is to be made * @pages: The size of the mapping * * Determine whether the allocation of a new virtual mapping by the current * task is permitted, returning 1 if permission is granted, 0 if not. */ int cap_vm_enough_memory(struct mm_struct *mm, long pages) { int cap_sys_admin = 0; if (cap_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN, CAP_OPT_NOAUDIT) == 0) cap_sys_admin = 1; return cap_sys_admin; } /* * cap_mmap_addr - check if able to map given addr * @addr: address attempting to be mapped * * If the process is attempting to map memory below dac_mmap_min_addr they need * CAP_SYS_RAWIO. The other parameters to this function are unused by the * capability security module. Returns 0 if this mapping should be allowed * -EPERM if not. */ int cap_mmap_addr(unsigned long addr) { int ret = 0; if (addr < dac_mmap_min_addr) { ret = cap_capable(current_cred(), &init_user_ns, CAP_SYS_RAWIO, CAP_OPT_NONE); /* set PF_SUPERPRIV if it turns out we allow the low mmap */ if (ret == 0) current->flags |= PF_SUPERPRIV; } return ret; } int cap_mmap_file(struct file *file, unsigned long reqprot, unsigned long prot, unsigned long flags) { return 0; } #ifdef CONFIG_SECURITY static struct security_hook_list capability_hooks[] __lsm_ro_after_init = { LSM_HOOK_INIT(capable, cap_capable), LSM_HOOK_INIT(settime, cap_settime), LSM_HOOK_INIT(ptrace_access_check, cap_ptrace_access_check), LSM_HOOK_INIT(ptrace_traceme, cap_ptrace_traceme), LSM_HOOK_INIT(capget, cap_capget), LSM_HOOK_INIT(capset, cap_capset), LSM_HOOK_INIT(bprm_creds_from_file, cap_bprm_creds_from_file), LSM_HOOK_INIT(inode_need_killpriv, cap_inode_need_killpriv), LSM_HOOK_INIT(inode_killpriv, cap_inode_killpriv), LSM_HOOK_INIT(inode_getsecurity, cap_inode_getsecurity), LSM_HOOK_INIT(mmap_addr, cap_mmap_addr), LSM_HOOK_INIT(mmap_file, cap_mmap_file), LSM_HOOK_INIT(task_fix_setuid, cap_task_fix_setuid), LSM_HOOK_INIT(task_prctl, cap_task_prctl), LSM_HOOK_INIT(task_setscheduler, cap_task_setscheduler), LSM_HOOK_INIT(task_setioprio, cap_task_setioprio), LSM_HOOK_INIT(task_setnice, cap_task_setnice), LSM_HOOK_INIT(vm_enough_memory, cap_vm_enough_memory), }; static int __init capability_init(void) { security_add_hooks(capability_hooks, ARRAY_SIZE(capability_hooks), "capability"); return 0; } DEFINE_LSM(capability) = { .name = "capability", .order = LSM_ORDER_FIRST, .init = capability_init, }; #endif /* CONFIG_SECURITY */
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 /* SPDX-License-Identifier: GPL-2.0-or-later */ /* Red Black Trees (C) 1999 Andrea Arcangeli <andrea@suse.de> linux/include/linux/rbtree.h To use rbtrees you'll have to implement your own insert and search cores. This will avoid us to use callbacks and to drop drammatically performances. I know it's not the cleaner way, but in C (not in C++) to get performances and genericity... See Documentation/core-api/rbtree.rst for documentation and samples. */ #ifndef _LINUX_RBTREE_H #define _LINUX_RBTREE_H #include <linux/kernel.h> #include <linux/stddef.h> #include <linux/rcupdate.h> struct rb_node { unsigned long __rb_parent_color; struct rb_node *rb_right; struct rb_node *rb_left; } __attribute__((aligned(sizeof(long)))); /* The alignment might seem pointless, but allegedly CRIS needs it */ struct rb_root { struct rb_node *rb_node; }; #define rb_parent(r) ((struct rb_node *)((r)->__rb_parent_color & ~3)) #define RB_ROOT (struct rb_root) { NULL, } #define rb_entry(ptr, type, member) container_of(ptr, type, member) #define RB_EMPTY_ROOT(root) (READ_ONCE((root)->rb_node) == NULL) /* 'empty' nodes are nodes that are known not to be inserted in an rbtree */ #define RB_EMPTY_NODE(node) \ ((node)->__rb_parent_color == (unsigned long)(node)) #define RB_CLEAR_NODE(node) \ ((node)->__rb_parent_color = (unsigned long)(node)) extern void rb_insert_color(struct rb_node *, struct rb_root *); extern void rb_erase(struct rb_node *, struct rb_root *); /* Find logical next and previous nodes in a tree */ extern struct rb_node *rb_next(const struct rb_node *); extern struct rb_node *rb_prev(const struct rb_node *); extern struct rb_node *rb_first(const struct rb_root *); extern struct rb_node *rb_last(const struct rb_root *); /* Postorder iteration - always visit the parent after its children */ extern struct rb_node *rb_first_postorder(const struct rb_root *); extern struct rb_node *rb_next_postorder(const struct rb_node *); /* Fast replacement of a single node without remove/rebalance/add/rebalance */ extern void rb_replace_node(struct rb_node *victim, struct rb_node *new, struct rb_root *root); extern void rb_replace_node_rcu(struct rb_node *victim, struct rb_node *new, struct rb_root *root); static inline void rb_link_node(struct rb_node *node, struct rb_node *parent, struct rb_node **rb_link) { node->__rb_parent_color = (unsigned long)parent; node->rb_left = node->rb_right = NULL; *rb_link = node; } static inline void rb_link_node_rcu(struct rb_node *node, struct rb_node *parent, struct rb_node **rb_link) { node->__rb_parent_color = (unsigned long)parent; node->rb_left = node->rb_right = NULL; rcu_assign_pointer(*rb_link, node); } #define rb_entry_safe(ptr, type, member) \ ({ typeof(ptr) ____ptr = (ptr); \ ____ptr ? rb_entry(____ptr, type, member) : NULL; \ }) /** * rbtree_postorder_for_each_entry_safe - iterate in post-order over rb_root of * given type allowing the backing memory of @pos to be invalidated * * @pos: the 'type *' to use as a loop cursor. * @n: another 'type *' to use as temporary storage * @root: 'rb_root *' of the rbtree. * @field: the name of the rb_node field within 'type'. * * rbtree_postorder_for_each_entry_safe() provides a similar guarantee as * list_for_each_entry_safe() and allows the iteration to continue independent * of changes to @pos by the body of the loop. * * Note, however, that it cannot handle other modifications that re-order the * rbtree it is iterating over. This includes calling rb_erase() on @pos, as * rb_erase() may rebalance the tree, causing us to miss some nodes. */ #define rbtree_postorder_for_each_entry_safe(pos, n, root, field) \ for (pos = rb_entry_safe(rb_first_postorder(root), typeof(*pos), field); \ pos && ({ n = rb_entry_safe(rb_next_postorder(&pos->field), \ typeof(*pos), field); 1; }); \ pos = n) /* * Leftmost-cached rbtrees. * * We do not cache the rightmost node based on footprint * size vs number of potential users that could benefit * from O(1) rb_last(). Just not worth it, users that want * this feature can always implement the logic explicitly. * Furthermore, users that want to cache both pointers may * find it a bit asymmetric, but that's ok. */ struct rb_root_cached { struct rb_root rb_root; struct rb_node *rb_leftmost; }; #define RB_ROOT_CACHED (struct rb_root_cached) { {NULL, }, NULL } /* Same as rb_first(), but O(1) */ #define rb_first_cached(root) (root)->rb_leftmost static inline void rb_insert_color_cached(struct rb_node *node, struct rb_root_cached *root, bool leftmost) { if (leftmost) root->rb_leftmost = node; rb_insert_color(node, &root->rb_root); } static inline void rb_erase_cached(struct rb_node *node, struct rb_root_cached *root) { if (root->rb_leftmost == node) root->rb_leftmost = rb_next(node); rb_erase(node, &root->rb_root); } static inline void rb_replace_node_cached(struct rb_node *victim, struct rb_node *new, struct rb_root_cached *root) { if (root->rb_leftmost == victim) root->rb_leftmost = new; rb_replace_node(victim, new, &root->rb_root); } #endif /* _LINUX_RBTREE_H */
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 /* SPDX-License-Identifier: GPL-2.0 */ #ifndef _LINUX_GENHD_H #define _LINUX_GENHD_H /* * genhd.h Copyright (C) 1992 Drew Eckhardt * Generic hard disk header file by * Drew Eckhardt * * <drew@colorado.edu> */ #include <linux/types.h> #include <linux/kdev_t.h> #include <linux/rcupdate.h> #include <linux/slab.h> #include <linux/percpu-refcount.h> #include <linux/uuid.h> #include <linux/blk_types.h> #include <asm/local.h> #define dev_to_disk(device) container_of((device), struct gendisk, part0.__dev) #define dev_to_part(device) container_of((device), struct hd_struct, __dev) #define disk_to_dev(disk) (&(disk)->part0.__dev) #define part_to_dev(part) (&((part)->__dev)) extern const struct device_type disk_type; extern struct device_type part_type; extern struct class block_class; #define DISK_MAX_PARTS 256 #define DISK_NAME_LEN 32 #include <linux/major.h> #include <linux/device.h> #include <linux/smp.h> #include <linux/string.h> #include <linux/fs.h> #include <linux/workqueue.h> #define PARTITION_META_INFO_VOLNAMELTH 64 /* * Enough for the string representation of any kind of UUID plus NULL. * EFI UUID is 36 characters. MSDOS UUID is 11 characters. */ #define PARTITION_META_INFO_UUIDLTH (UUID_STRING_LEN + 1) struct partition_meta_info { char uuid[PARTITION_META_INFO_UUIDLTH]; u8 volname[PARTITION_META_INFO_VOLNAMELTH]; }; struct hd_struct { sector_t start_sect; /* * nr_sects is protected by sequence counter. One might extend a * partition while IO is happening to it and update of nr_sects * can be non-atomic on 32bit machines with 64bit sector_t. */ sector_t nr_sects; #if BITS_PER_LONG==32 && defined(CONFIG_SMP) seqcount_t nr_sects_seq; #endif unsigned long stamp; struct disk_stats __percpu *dkstats; struct percpu_ref ref; struct device __dev; struct kobject *holder_dir; int policy, partno; struct partition_meta_info *info; #ifdef CONFIG_FAIL_MAKE_REQUEST int make_it_fail; #endif struct rcu_work rcu_work; }; /** * DOC: genhd capability flags * * ``GENHD_FL_REMOVABLE`` (0x0001): indicates that the block device * gives access to removable media. * When set, the device remains present even when media is not * inserted. * Must not be set for devices which are removed entirely when the * media is removed. * * ``GENHD_FL_CD`` (0x0008): the block device is a CD-ROM-style * device. * Affects responses to the ``CDROM_GET_CAPABILITY`` ioctl. * * ``GENHD_FL_UP`` (0x0010): indicates that the block device is "up", * with a similar meaning to network interfaces. * * ``GENHD_FL_SUPPRESS_PARTITION_INFO`` (0x0020): don't include * partition information in ``/proc/partitions`` or in the output of * printk_all_partitions(). * Used for the null block device and some MMC devices. * * ``GENHD_FL_EXT_DEVT`` (0x0040): the driver supports extended * dynamic ``dev_t``, i.e. it wants extended device numbers * (``BLOCK_EXT_MAJOR``). * This affects the maximum number of partitions. * * ``GENHD_FL_NATIVE_CAPACITY`` (0x0080): based on information in the * partition table, the device's capacity has been extended to its * native capacity; i.e. the device has hidden capacity used by one * of the partitions (this is a flag used so that native capacity is * only ever unlocked once). * * ``GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE`` (0x0100): event polling is * blocked whenever a writer holds an exclusive lock. * * ``GENHD_FL_NO_PART_SCAN`` (0x0200): partition scanning is disabled. * Used for loop devices in their default settings and some MMC * devices. * * ``GENHD_FL_HIDDEN`` (0x0400): the block device is hidden; it * doesn't produce events, doesn't appear in sysfs, and doesn't have * an associated ``bdev``. * Implies ``GENHD_FL_SUPPRESS_PARTITION_INFO`` and * ``GENHD_FL_NO_PART_SCAN``. * Used for multipath devices. */ #define GENHD_FL_REMOVABLE 0x0001 /* 2 is unused (used to be GENHD_FL_DRIVERFS) */ /* 4 is unused (used to be GENHD_FL_MEDIA_CHANGE_NOTIFY) */ #define GENHD_FL_CD 0x0008 #define GENHD_FL_UP 0x0010 #define GENHD_FL_SUPPRESS_PARTITION_INFO 0x0020 #define GENHD_FL_EXT_DEVT 0x0040 #define GENHD_FL_NATIVE_CAPACITY 0x0080 #define GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE 0x0100 #define GENHD_FL_NO_PART_SCAN 0x0200 #define GENHD_FL_HIDDEN 0x0400 enum { DISK_EVENT_MEDIA_CHANGE = 1 << 0, /* media changed */ DISK_EVENT_EJECT_REQUEST = 1 << 1, /* eject requested */ }; enum { /* Poll even if events_poll_msecs is unset */ DISK_EVENT_FLAG_POLL = 1 << 0, /* Forward events to udev */ DISK_EVENT_FLAG_UEVENT = 1 << 1, }; struct disk_part_tbl { struct rcu_head rcu_head; int len; struct hd_struct __rcu *last_lookup; struct hd_struct __rcu *part[]; }; struct disk_events; struct badblocks; struct blk_integrity { const struct blk_integrity_profile *profile; unsigned char flags; unsigned char tuple_size; unsigned char interval_exp; unsigned char tag_size; }; struct gendisk { /* major, first_minor and minors are input parameters only, * don't use directly. Use disk_devt() and disk_max_parts(). */ int major; /* major number of driver */ int first_minor; int minors; /* maximum number of minors, =1 for * disks that can't be partitioned. */ char disk_name[DISK_NAME_LEN]; /* name of major driver */ unsigned short events; /* supported events */ unsigned short event_flags; /* flags related to event processing */ /* Array of pointers to partitions indexed by partno. * Protected with matching bdev lock but stat and other * non-critical accesses use RCU. Always access through * helpers. */ struct disk_part_tbl __rcu *part_tbl; struct hd_struct part0; const struct block_device_operations *fops; struct request_queue *queue; void *private_data; int flags; unsigned long state; #define GD_NEED_PART_SCAN 0 struct rw_semaphore lookup_sem; struct kobject *slave_dir; struct timer_rand_state *random; atomic_t sync_io; /* RAID */ struct disk_events *ev; #ifdef CONFIG_BLK_DEV_INTEGRITY struct kobject integrity_kobj; #endif /* CONFIG_BLK_DEV_INTEGRITY */ #if IS_ENABLED(CONFIG_CDROM) struct cdrom_device_info *cdi; #endif int node_id; struct badblocks *bb; struct lockdep_map lockdep_map; }; #if IS_REACHABLE(CONFIG_CDROM) #define disk_to_cdi(disk) ((disk)->cdi) #else #define disk_to_cdi(disk) NULL #endif static inline struct gendisk *part_to_disk(struct hd_struct *part) { if (likely(part)) { if (part->partno) return dev_to_disk(part_to_dev(part)->parent); else return dev_to_disk(part_to_dev(part)); } return NULL; } static inline int disk_max_parts(struct gendisk *disk) { if (disk->flags & GENHD_FL_EXT_DEVT) return DISK_MAX_PARTS; return disk->minors; } static inline bool disk_part_scan_enabled(struct gendisk *disk) { return disk_max_parts(disk) > 1 && !(disk->flags & GENHD_FL_NO_PART_SCAN); } static inline dev_t disk_devt(struct gendisk *disk) { return MKDEV(disk->major, disk->first_minor); } static inline dev_t part_devt(struct hd_struct *part) { return part_to_dev(part)->devt; } extern struct hd_struct *__disk_get_part(struct gendisk *disk, int partno); extern struct hd_struct *disk_get_part(struct gendisk *disk, int partno); static inline void disk_put_part(struct hd_struct *part) { if (likely(part)) put_device(part_to_dev(part)); } static inline void hd_sects_seq_init(struct hd_struct *p) { #if BITS_PER_LONG==32 && defined(CONFIG_SMP) seqcount_init(&p->nr_sects_seq); #endif } /* * Smarter partition iterator without context limits. */ #define DISK_PITER_REVERSE (1 << 0) /* iterate in the reverse direction */ #define DISK_PITER_INCL_EMPTY (1 << 1) /* include 0-sized parts */ #define DISK_PITER_INCL_PART0 (1 << 2) /* include partition 0 */ #define DISK_PITER_INCL_EMPTY_PART0 (1 << 3) /* include empty partition 0 */ struct disk_part_iter { struct gendisk *disk; struct hd_struct *part; int idx; unsigned int flags; }; extern void disk_part_iter_init(struct disk_part_iter *piter, struct gendisk *disk, unsigned int flags); extern struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter); extern void disk_part_iter_exit(struct disk_part_iter *piter); extern bool disk_has_partitions(struct gendisk *disk); /* block/genhd.c */ extern void device_add_disk(struct device *parent, struct gendisk *disk, const struct attribute_group **groups); static inline void add_disk(struct gendisk *disk) { device_add_disk(NULL, disk, NULL); } extern void device_add_disk_no_queue_reg(struct device *parent, struct gendisk *disk); static inline void add_disk_no_queue_reg(struct gendisk *disk) { device_add_disk_no_queue_reg(NULL, disk); } extern void del_gendisk(struct gendisk *gp); extern struct gendisk *get_gendisk(dev_t dev, int *partno); extern struct block_device *bdget_disk(struct gendisk *disk, int partno); extern void set_device_ro(struct block_device *bdev, int flag); extern void set_disk_ro(struct gendisk *disk, int flag); static inline int get_disk_ro(struct gendisk *disk) { return disk->part0.policy; } extern void disk_block_events(struct gendisk *disk); extern void disk_unblock_events(struct gendisk *disk); extern void disk_flush_events(struct gendisk *disk, unsigned int mask); bool set_capacity_revalidate_and_notify(struct gendisk *disk, sector_t size, bool update_bdev); /* drivers/char/random.c */ extern void add_disk_randomness(struct gendisk *disk) __latent_entropy; extern void rand_initialize_disk(struct gendisk *disk); static inline sector_t get_start_sect(struct block_device *bdev) { return bdev->bd_part->start_sect; } static inline sector_t get_capacity(struct gendisk *disk) { return disk->part0.nr_sects; } static inline void set_capacity(struct gendisk *disk, sector_t size) { disk->part0.nr_sects = size; } int bdev_disk_changed(struct block_device *bdev, bool invalidate); int blk_add_partitions(struct gendisk *disk, struct block_device *bdev); int blk_drop_partitions(struct block_device *bdev); extern struct gendisk *__alloc_disk_node(int minors, int node_id); extern struct kobject *get_disk_and_module(struct gendisk *disk); extern void put_disk(struct gendisk *disk); extern void put_disk_and_module(struct gendisk *disk); extern void blk_register_region(dev_t devt, unsigned long range, struct module *module, struct kobject *(*probe)(dev_t, int *, void *), int (*lock)(dev_t, void *), void *data); extern void blk_unregister_region(dev_t devt, unsigned long range); #define alloc_disk_node(minors, node_id) \ ({ \ static struct lock_class_key __key; \ const char *__name; \ struct gendisk *__disk; \ \ __name = "(gendisk_completion)"#minors"("#node_id")"; \ \ __disk = __alloc_disk_node(minors, node_id); \ \ if (__disk) \ lockdep_init_map(&__disk->lockdep_map, __name, &__key, 0); \ \ __disk; \ }) #define alloc_disk(minors) alloc_disk_node(minors, NUMA_NO_NODE) int register_blkdev(unsigned int major, const char *name); void unregister_blkdev(unsigned int major, const char *name); void revalidate_disk_size(struct gendisk *disk, bool verbose); bool bdev_check_media_change(struct block_device *bdev); int __invalidate_device(struct block_device *bdev, bool kill_dirty); void bd_set_nr_sectors(struct block_device *bdev, sector_t sectors); /* for drivers/char/raw.c: */ int blkdev_ioctl(struct block_device *, fmode_t, unsigned, unsigned long); long compat_blkdev_ioctl(struct file *, unsigned, unsigned long); #ifdef CONFIG_SYSFS int bd_link_disk_holder(struct block_device *bdev, struct gendisk *disk); void bd_unlink_disk_holder(struct block_device *bdev, struct gendisk *disk); #else static inline int bd_link_disk_holder(struct block_device *bdev, struct gendisk *disk) { return 0; } static inline void bd_unlink_disk_holder(struct block_device *bdev, struct gendisk *disk) { } #endif /* CONFIG_SYSFS */ #ifdef CONFIG_BLOCK void printk_all_partitions(void); dev_t blk_lookup_devt(const char *name, int partno); #else /* CONFIG_BLOCK */ static inline void printk_all_partitions(void) { } static inline dev_t blk_lookup_devt(const char *name, int partno) { dev_t devt = MKDEV(0, 0); return devt; } #endif /* CONFIG_BLOCK */ #endif /* _LINUX_GENHD_H */
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 /* SPDX-License-Identifier: GPL-2.0-or-later */ /* * Definitions for the 'struct skb_array' datastructure. * * Author: * Michael S. Tsirkin <mst@redhat.com> * * Copyright (C) 2016 Red Hat, Inc. * * Limited-size FIFO of skbs. Can be used more or less whenever * sk_buff_head can be used, except you need to know the queue size in * advance. * Implemented as a type-safe wrapper around ptr_ring. */ #ifndef _LINUX_SKB_ARRAY_H #define _LINUX_SKB_ARRAY_H 1 #ifdef __KERNEL__ #include <linux/ptr_ring.h> #include <linux/skbuff.h> #include <linux/if_vlan.h> #endif struct skb_array { struct ptr_ring ring; }; /* Might be slightly faster than skb_array_full below, but callers invoking * this in a loop must use a compiler barrier, for example cpu_relax(). */ static inline bool __skb_array_full(struct skb_array *a) { return __ptr_ring_full(&a->ring); } static inline bool skb_array_full(struct skb_array *a) { return ptr_ring_full(&a->ring); } static inline int skb_array_produce(struct skb_array *a, struct sk_buff *skb) { return ptr_ring_produce(&a->ring, skb); } static inline int skb_array_produce_irq(struct skb_array *a, struct sk_buff *skb) { return ptr_ring_produce_irq(&a->ring, skb); } static inline int skb_array_produce_bh(struct skb_array *a, struct sk_buff *skb) { return ptr_ring_produce_bh(&a->ring, skb); } static inline int skb_array_produce_any(struct skb_array *a, struct sk_buff *skb) { return ptr_ring_produce_any(&a->ring, skb); } /* Might be slightly faster than skb_array_empty below, but only safe if the * array is never resized. Also, callers invoking this in a loop must take care * to use a compiler barrier, for example cpu_relax(). */ static inline bool __skb_array_empty(struct skb_array *a) { return __ptr_ring_empty(&a->ring); } static inline struct sk_buff *__skb_array_peek(struct skb_array *a) { return __ptr_ring_peek(&a->ring); } static inline bool skb_array_empty(struct skb_array *a) { return ptr_ring_empty(&a->ring); } static inline bool skb_array_empty_bh(struct skb_array *a) { return ptr_ring_empty_bh(&a->ring); } static inline bool skb_array_empty_irq(struct skb_array *a) { return ptr_ring_empty_irq(&a->ring); } static inline bool skb_array_empty_any(struct skb_array *a) { return ptr_ring_empty_any(&a->ring); } static inline struct sk_buff *__skb_array_consume(struct skb_array *a) { return __ptr_ring_consume(&a->ring); } static inline struct sk_buff *skb_array_consume(struct skb_array *a) { return ptr_ring_consume(&a->ring); } static inline int skb_array_consume_batched(struct skb_array *a, struct sk_buff **array, int n) { return ptr_ring_consume_batched(&a->ring, (void **)array, n); } static inline struct sk_buff *skb_array_consume_irq(struct skb_array *a) { return ptr_ring_consume_irq(&a->ring); } static inline int skb_array_consume_batched_irq(struct skb_array *a, struct sk_buff **array, int n) { return ptr_ring_consume_batched_irq(&a->ring, (void **)array, n); } static inline struct sk_buff *skb_array_consume_any(struct skb_array *a) { return ptr_ring_consume_any(&a->ring); } static inline int skb_array_consume_batched_any(struct skb_array *a, struct sk_buff **array, int n) { return ptr_ring_consume_batched_any(&a->ring, (void **)array, n); } static inline struct sk_buff *skb_array_consume_bh(struct skb_array *a) { return ptr_ring_consume_bh(&a->ring); } static inline int skb_array_consume_batched_bh(struct skb_array *a, struct sk_buff **array, int n) { return ptr_ring_consume_batched_bh(&a->ring, (void **)array, n); } static inline int __skb_array_len_with_tag(struct sk_buff *skb) { if (likely(skb)) { int len = skb->len; if (skb_vlan_tag_present(skb)) len += VLAN_HLEN; return len; } else { return 0; } } static inline int skb_array_peek_len(struct skb_array *a) { return PTR_RING_PEEK_CALL(&a->ring, __skb_array_len_with_tag); } static inline int skb_array_peek_len_irq(struct skb_array *a) { return PTR_RING_PEEK_CALL_IRQ(&a->ring, __skb_array_len_with_tag); } static inline int skb_array_peek_len_bh(struct skb_array *a) { return PTR_RING_PEEK_CALL_BH(&a->ring, __skb_array_len_with_tag); } static inline int skb_array_peek_len_any(struct skb_array *a) { return PTR_RING_PEEK_CALL_ANY(&a->ring, __skb_array_len_with_tag); } static inline int skb_array_init(struct skb_array *a, int size, gfp_t gfp) { return ptr_ring_init(&a->ring, size, gfp); } static void __skb_array_destroy_skb(void *ptr) { kfree_skb(ptr); } static inline void skb_array_unconsume(struct skb_array *a, struct sk_buff **skbs, int n) { ptr_ring_unconsume(&a->ring, (void **)skbs, n, __skb_array_destroy_skb); } static inline int skb_array_resize(struct skb_array *a, int size, gfp_t gfp) { return ptr_ring_resize(&a->ring, size, gfp, __skb_array_destroy_skb); } static inline int skb_array_resize_multiple(struct skb_array **rings, int nrings, unsigned int size, gfp_t gfp) { BUILD_BUG_ON(offsetof(struct skb_array, ring)); return ptr_ring_resize_multiple((struct ptr_ring **)rings, nrings, size, gfp, __skb_array_destroy_skb); } static inline void skb_array_cleanup(struct skb_array *a) { ptr_ring_cleanup(&a->ring, __skb_array_destroy_skb); } #endif /* _LINUX_SKB_ARRAY_H */
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 /* SPDX-License-Identifier: GPL-2.0-or-later */ #ifndef _LINUX_IO_URING_H #define _LINUX_IO_URING_H #include <linux/sched.h> #include <linux/xarray.h> struct io_identity { struct files_struct *files; struct mm_struct *mm; #ifdef CONFIG_BLK_CGROUP struct cgroup_subsys_state *blkcg_css; #endif const struct cred *creds; struct nsproxy *nsproxy; struct fs_struct *fs; unsigned long fsize; #ifdef CONFIG_AUDIT kuid_t loginuid; unsigned int sessionid; #endif refcount_t count; }; struct io_uring_task { /* submission side */ struct xarray xa; struct wait_queue_head wait; struct file *last; struct percpu_counter inflight; struct io_identity __identity; struct io_identity *identity; atomic_t in_idle; bool sqpoll; }; #if defined(CONFIG_IO_URING) struct sock *io_uring_get_socket(struct file *file); void __io_uring_task_cancel(void); void __io_uring_files_cancel(struct files_struct *files); void __io_uring_free(struct task_struct *tsk); static inline void io_uring_task_cancel(void) { if (current->io_uring && !xa_empty(&current->io_uring->xa)) __io_uring_task_cancel(); } static inline void io_uring_files_cancel(struct files_struct *files) { if (current->io_uring && !xa_empty(&current->io_uring->xa)) __io_uring_files_cancel(files); } static inline void io_uring_free(struct task_struct *tsk) { if (tsk->io_uring) __io_uring_free(tsk); } #else static inline struct sock *io_uring_get_socket(struct file *file) { return NULL; } static inline void io_uring_task_cancel(void) { } static inline void io_uring_files_cancel(struct files_struct *files) { } static inline void io_uring_free(struct task_struct *tsk) { } #endif #endif
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 /* SPDX-License-Identifier: GPL-2.0 */ #ifndef __ASM_X86_XSAVE_H #define __ASM_X86_XSAVE_H #include <linux/uaccess.h> #include <linux/types.h> #include <asm/processor.h> #include <asm/user.h> /* Bit 63 of XCR0 is reserved for future expansion */ #define XFEATURE_MASK_EXTEND (~(XFEATURE_MASK_FPSSE | (1ULL << 63))) #define XSTATE_CPUID 0x0000000d #define FXSAVE_SIZE 512 #define XSAVE_HDR_SIZE 64 #define XSAVE_HDR_OFFSET FXSAVE_SIZE #define XSAVE_YMM_SIZE 256 #define XSAVE_YMM_OFFSET (XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET) #define XSAVE_ALIGNMENT 64 /* All currently supported user features */ #define XFEATURE_MASK_USER_SUPPORTED (XFEATURE_MASK_FP | \ XFEATURE_MASK_SSE | \ XFEATURE_MASK_YMM | \ XFEATURE_MASK_OPMASK | \ XFEATURE_MASK_ZMM_Hi256 | \ XFEATURE_MASK_Hi16_ZMM | \ XFEATURE_MASK_PKRU | \ XFEATURE_MASK_BNDREGS | \ XFEATURE_MASK_BNDCSR) /* All currently supported supervisor features */ #define XFEATURE_MASK_SUPERVISOR_SUPPORTED (XFEATURE_MASK_PASID) /* * A supervisor state component may not always contain valuable information, * and its size may be huge. Saving/restoring such supervisor state components * at each context switch can cause high CPU and space overhead, which should * be avoided. Such supervisor state components should only be saved/restored * on demand. The on-demand dynamic supervisor features are set in this mask. * * Unlike the existing supported supervisor features, a dynamic supervisor * feature does not allocate a buffer in task->fpu, and the corresponding * supervisor state component cannot be saved/restored at each context switch. * * To support a dynamic supervisor feature, a developer should follow the * dos and don'ts as below: * - Do dynamically allocate a buffer for the supervisor state component. * - Do manually invoke the XSAVES/XRSTORS instruction to save/restore the * state component to/from the buffer. * - Don't set the bit corresponding to the dynamic supervisor feature in * IA32_XSS at run time, since it has been set at boot time. */ #define XFEATURE_MASK_DYNAMIC (XFEATURE_MASK_LBR) /* * Unsupported supervisor features. When a supervisor feature in this mask is * supported in the future, move it to the supported supervisor feature mask. */ #define XFEATURE_MASK_SUPERVISOR_UNSUPPORTED (XFEATURE_MASK_PT) /* All supervisor states including supported and unsupported states. */ #define XFEATURE_MASK_SUPERVISOR_ALL (XFEATURE_MASK_SUPERVISOR_SUPPORTED | \ XFEATURE_MASK_DYNAMIC | \ XFEATURE_MASK_SUPERVISOR_UNSUPPORTED) #ifdef CONFIG_X86_64 #define REX_PREFIX "0x48, " #else #define REX_PREFIX #endif extern u64 xfeatures_mask_all; static inline u64 xfeatures_mask_supervisor(void) { return xfeatures_mask_all & XFEATURE_MASK_SUPERVISOR_SUPPORTED; } static inline u64 xfeatures_mask_user(void) { return xfeatures_mask_all & XFEATURE_MASK_USER_SUPPORTED; } static inline u64 xfeatures_mask_dynamic(void) { if (!boot_cpu_has(X86_FEATURE_ARCH_LBR)) return XFEATURE_MASK_DYNAMIC & ~XFEATURE_MASK_LBR; return XFEATURE_MASK_DYNAMIC; } extern u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS]; extern void __init update_regset_xstate_info(unsigned int size, u64 xstate_mask); void *get_xsave_addr(struct xregs_state *xsave, int xfeature_nr); const void *get_xsave_field_ptr(int xfeature_nr); int using_compacted_format(void); int xfeature_size(int xfeature_nr); struct membuf; void copy_xstate_to_kernel(struct membuf to, struct xregs_state *xsave); int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf); int copy_user_to_xstate(struct xregs_state *xsave, const void __user *ubuf); void copy_supervisor_to_kernel(struct xregs_state *xsave); void copy_dynamic_supervisor_to_kernel(struct xregs_state *xstate, u64 mask); void copy_kernel_to_dynamic_supervisor(struct xregs_state *xstate, u64 mask); /* Validate an xstate header supplied by userspace (ptrace or sigreturn) */ int validate_user_xstate_header(const struct xstate_header *hdr); #endif
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 /* SPDX-License-Identifier: GPL-2.0 */ #ifndef _LINUX_MATH64_H #define _LINUX_MATH64_H #include <linux/types.h> #include <vdso/math64.h> #include <asm/div64.h> #if BITS_PER_LONG == 64 #define div64_long(x, y) div64_s64((x), (y)) #define div64_ul(x, y) div64_u64((x), (y)) /** * div_u64_rem - unsigned 64bit divide with 32bit divisor with remainder * @dividend: unsigned 64bit dividend * @divisor: unsigned 32bit divisor * @remainder: pointer to unsigned 32bit remainder * * Return: sets ``*remainder``, then returns dividend / divisor * * This is commonly provided by 32bit archs to provide an optimized 64bit * divide. */ static inline u64 div_u64_rem(u64 dividend, u32 divisor, u32 *remainder) { *remainder = dividend % divisor; return dividend / divisor; } /* * div_s64_rem - signed 64bit divide with 32bit divisor with remainder * @dividend: signed 64bit dividend * @divisor: signed 32bit divisor * @remainder: pointer to signed 32bit remainder * * Return: sets ``*remainder``, then returns dividend / divisor */ static inline s64 div_s64_rem(s64 dividend, s32 divisor, s32 *remainder) { *remainder = dividend % divisor; return dividend / divisor; } /* * div64_u64_rem - unsigned 64bit divide with 64bit divisor and remainder * @dividend: unsigned 64bit dividend * @divisor: unsigned 64bit divisor * @remainder: pointer to unsigned 64bit remainder * * Return: sets ``*remainder``, then returns dividend / divisor */ static inline u64 div64_u64_rem(u64 dividend, u64 divisor, u64 *remainder) { *remainder = dividend % divisor; return dividend / divisor; } /* * div64_u64 - unsigned 64bit divide with 64bit divisor * @dividend: unsigned 64bit dividend * @divisor: unsigned 64bit divisor * * Return: dividend / divisor */ static inline u64 div64_u64(u64 dividend, u64 divisor) { return dividend / divisor; } /* * div64_s64 - signed 64bit divide with 64bit divisor * @dividend: signed 64bit dividend * @divisor: signed 64bit divisor * * Return: dividend / divisor */ static inline s64 div64_s64(s64 dividend, s64 divisor) { return dividend / divisor; } #elif BITS_PER_LONG == 32 #define div64_long(x, y) div_s64((x), (y)) #define div64_ul(x, y) div_u64((x), (y)) #ifndef div_u64_rem static inline u64 div_u64_rem(u64 dividend, u32 divisor, u32 *remainder) { *remainder = do_div(dividend, divisor); return dividend; } #endif #ifndef div_s64_rem extern s64 div_s64_rem(s64 dividend, s32 divisor, s32 *remainder); #endif #ifndef div64_u64_rem extern u64 div64_u64_rem(u64 dividend, u64 divisor, u64 *remainder); #endif #ifndef div64_u64 extern u64 div64_u64(u64 dividend, u64 divisor); #endif #ifndef div64_s64 extern s64 div64_s64(s64 dividend, s64 divisor); #endif #endif /* BITS_PER_LONG */ /** * div_u64 - unsigned 64bit divide with 32bit divisor * @dividend: unsigned 64bit dividend * @divisor: unsigned 32bit divisor * * This is the most common 64bit divide and should be used if possible, * as many 32bit archs can optimize this variant better than a full 64bit * divide. */ #ifndef div_u64 static inline u64 div_u64(u64 dividend, u32 divisor) { u32 remainder; return div_u64_rem(dividend, divisor, &remainder); } #endif /** * div_s64 - signed 64bit divide with 32bit divisor * @dividend: signed 64bit dividend * @divisor: signed 32bit divisor */ #ifndef div_s64 static inline s64 div_s64(s64 dividend, s32 divisor) { s32 remainder; return div_s64_rem(dividend, divisor, &remainder); } #endif u32 iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder); #ifndef mul_u32_u32 /* * Many a GCC version messes this up and generates a 64x64 mult :-( */ static inline u64 mul_u32_u32(u32 a, u32 b) { return (u64)a * b; } #endif #if defined(CONFIG_ARCH_SUPPORTS_INT128) && defined(__SIZEOF_INT128__) #ifndef mul_u64_u32_shr static inline u64 mul_u64_u32_shr(u64 a, u32 mul, unsigned int shift) { return (u64)(((unsigned __int128)a * mul) >> shift); } #endif /* mul_u64_u32_shr */ #ifndef mul_u64_u64_shr static inline u64 mul_u64_u64_shr(u64 a, u64 mul, unsigned int shift) { return (u64)(((unsigned __int128)a * mul) >> shift); } #endif /* mul_u64_u64_shr */ #else #ifndef mul_u64_u32_shr static inline u64 mul_u64_u32_shr(u64 a, u32 mul, unsigned int shift) { u32 ah, al; u64 ret; al = a; ah = a >> 32; ret = mul_u32_u32(al, mul) >> shift; if (ah) ret += mul_u32_u32(ah, mul) << (32 - shift); return ret; } #endif /* mul_u64_u32_shr */ #ifndef mul_u64_u64_shr static inline u64 mul_u64_u64_shr(u64 a, u64 b, unsigned int shift) { union { u64 ll; struct { #ifdef __BIG_ENDIAN u32 high, low; #else u32 low, high; #endif } l; } rl, rm, rn, rh, a0, b0; u64 c; a0.ll = a; b0.ll = b; rl.ll = mul_u32_u32(a0.l.low, b0.l.low); rm.ll = mul_u32_u32(a0.l.low, b0.l.high); rn.ll = mul_u32_u32(a0.l.high, b0.l.low); rh.ll = mul_u32_u32(a0.l.high, b0.l.high); /* * Each of these lines computes a 64-bit intermediate result into "c", * starting at bits 32-95. The low 32-bits go into the result of the * multiplication, the high 32-bits are carried into the next step. */ rl.l.high = c = (u64)rl.l.high + rm.l.low + rn.l.low; rh.l.low = c = (c >> 32) + rm.l.high + rn.l.high + rh.l.low; rh.l.high = (c >> 32) + rh.l.high; /* * The 128-bit result of the multiplication is in rl.ll and rh.ll, * shift it right and throw away the high part of the result. */ if (shift == 0) return rl.ll; if (shift < 64) return (rl.ll >> shift) | (rh.ll << (64 - shift)); return rh.ll >> (shift & 63); } #endif /* mul_u64_u64_shr */ #endif #ifndef mul_u64_u32_div static inline u64 mul_u64_u32_div(u64 a, u32 mul, u32 divisor) { union { u64 ll; struct { #ifdef __BIG_ENDIAN u32 high, low; #else u32 low, high; #endif } l; } u, rl, rh; u.ll = a; rl.ll = mul_u32_u32(u.l.low, mul); rh.ll = mul_u32_u32(u.l.high, mul) + rl.l.high; /* Bits 32-63 of the result will be in rh.l.low. */ rl.l.high = do_div(rh.ll, divisor); /* Bits 0-31 of the result will be in rl.l.low. */ do_div(rl.ll, divisor); rl.l.high = rh.l.low; return rl.ll; } #endif /* mul_u64_u32_div */ u64 mul_u64_u64_div_u64(u64 a, u64 mul, u64 div); #define DIV64_U64_ROUND_UP(ll, d) \ ({ u64 _tmp = (d); div64_u64((ll) + _tmp - 1, _tmp); }) /** * DIV64_U64_ROUND_CLOSEST - unsigned 64bit divide with 64bit divisor rounded to nearest integer * @dividend: unsigned 64bit dividend * @divisor: unsigned 64bit divisor * * Divide unsigned 64bit dividend by unsigned 64bit divisor * and round to closest integer. * * Return: dividend / divisor rounded to nearest integer */ #define DIV64_U64_ROUND_CLOSEST(dividend, divisor) \ ({ u64 _tmp = (divisor); div64_u64((dividend) + _tmp / 2, _tmp); }) /* * DIV_S64_ROUND_CLOSEST - signed 64bit divide with 32bit divisor rounded to nearest integer * @dividend: signed 64bit dividend * @divisor: signed 32bit divisor * * Divide signed 64bit dividend by signed 32bit divisor * and round to closest integer. * * Return: dividend / divisor rounded to nearest integer */ #define DIV_S64_ROUND_CLOSEST(dividend, divisor)( \ { \ s64 __x = (dividend); \ s32 __d = (divisor); \ ((__x > 0) == (__d > 0)) ? \ div_s64((__x + (__d / 2)), __d) : \ div_s64((__x - (__d / 2)), __d); \ } \ ) #endif /* _LINUX_MATH64_H */
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 /* SPDX-License-Identifier: GPL-2.0 */ #undef TRACE_SYSTEM #define TRACE_SYSTEM mmap #if !defined(_TRACE_MMAP_H) || defined(TRACE_HEADER_MULTI_READ) #define _TRACE_MMAP_H #include <linux/tracepoint.h> TRACE_EVENT(vm_unmapped_area, TP_PROTO(unsigned long addr, struct vm_unmapped_area_info *info), TP_ARGS(addr, info), TP_STRUCT__entry( __field(unsigned long, addr) __field(unsigned long, total_vm) __field(unsigned long, flags) __field(unsigned long, length) __field(unsigned long, low_limit) __field(unsigned long, high_limit) __field(unsigned long, align_mask) __field(unsigned long, align_offset) ), TP_fast_assign( __entry->addr = addr; __entry->total_vm = current->mm->total_vm; __entry->flags = info->flags; __entry->length = info->length; __entry->low_limit = info->low_limit; __entry->high_limit = info->high_limit; __entry->align_mask = info->align_mask; __entry->align_offset = info->align_offset; ), TP_printk("addr=0x%lx err=%ld total_vm=0x%lx flags=0x%lx len=0x%lx lo=0x%lx hi=0x%lx mask=0x%lx ofs=0x%lx\n", IS_ERR_VALUE(__entry->addr) ? 0 : __entry->addr, IS_ERR_VALUE(__entry->addr) ? __entry->addr : 0, __entry->total_vm, __entry->flags, __entry->length, __entry->low_limit, __entry->high_limit, __entry->align_mask, __entry->align_offset) ); #endif /* This part must be outside protection */ #include <trace/define_trace.h>
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 /* SPDX-License-Identifier: GPL-2.0 */ /* * generic net pointers */ #ifndef __NET_GENERIC_H__ #define __NET_GENERIC_H__ #include <linux/bug.h> #include <linux/rcupdate.h> /* * Generic net pointers are to be used by modules to put some private * stuff on the struct net without explicit struct net modification * * The rules are simple: * 1. set pernet_operations->id. After register_pernet_device you * will have the id of your private pointer. * 2. set pernet_operations->size to have the code allocate and free * a private structure pointed to from struct net. * 3. do not change this pointer while the net is alive; * 4. do not try to have any private reference on the net_generic object. * * After accomplishing all of the above, the private pointer can be * accessed with the net_generic() call. */ struct net_generic { union { struct { unsigned int len; struct rcu_head rcu; } s; void *ptr[0]; }; }; static inline void *net_generic(const struct net *net, unsigned int id) { struct net_generic *ng; void *ptr; rcu_read_lock(); ng = rcu_dereference(net->gen); ptr = ng->ptr[id]; rcu_read_unlock(); return ptr; } #endif
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4573 4574 4575 4576 4577 4578 4579 4580 4581 4582 4583 4584 4585 4586 4587 4588 4589 4590 4591 4592 4593 4594 4595 4596 4597 4598 4599 4600 4601 4602 4603 4604 4605 4606 4607 4608 4609 4610 4611 4612 4613 4614 4615 4616 4617 4618 4619 4620 4621 4622 4623 4624 4625 4626 4627 4628 4629 4630 4631 4632 4633 4634 4635 4636 4637 4638 4639 4640 4641 4642 4643 4644 4645 4646 4647 4648 4649 4650 4651 4652 4653 4654 4655 4656 4657 4658 4659 4660 4661 4662 4663 4664 4665 4666 4667 4668 4669 4670 // SPDX-License-Identifier: GPL-2.0 /* * linux/fs/namei.c * * Copyright (C) 1991, 1992 Linus Torvalds */ /* * Some corrections by tytso. */ /* [Feb 1997 T. Schoebel-Theuer] Complete rewrite of the pathname * lookup logic. */ /* [Feb-Apr 2000, AV] Rewrite to the new namespace architecture. */ #include <linux/init.h> #include <linux/export.h> #include <linux/kernel.h> #include <linux/slab.h> #include <linux/fs.h> #include <linux/namei.h> #include <linux/pagemap.h> #include <linux/fsnotify.h> #include <linux/personality.h> #include <linux/security.h> #include <linux/ima.h> #include <linux/syscalls.h> #include <linux/mount.h> #include <linux/audit.h> #include <linux/capability.h> #include <linux/file.h> #include <linux/fcntl.h> #include <linux/device_cgroup.h> #include <linux/fs_struct.h> #include <linux/posix_acl.h> #include <linux/hash.h> #include <linux/bitops.h> #include <linux/init_task.h> #include <linux/uaccess.h> #include "internal.h" #include "mount.h" /* [Feb-1997 T. Schoebel-Theuer] * Fundamental changes in the pathname lookup mechanisms (namei) * were necessary because of omirr. The reason is that omirr needs * to know the _real_ pathname, not the user-supplied one, in case * of symlinks (and also when transname replacements occur). * * The new code replaces the old recursive symlink resolution with * an iterative one (in case of non-nested symlink chains). It does * this with calls to <fs>_follow_link(). * As a side effect, dir_namei(), _namei() and follow_link() are now * replaced with a single function lookup_dentry() that can handle all * the special cases of the former code. * * With the new dcache, the pathname is stored at each inode, at least as * long as the refcount of the inode is positive. As a side effect, the * size of the dcache depends on the inode cache and thus is dynamic. * * [29-Apr-1998 C. Scott Ananian] Updated above description of symlink * resolution to correspond with current state of the code. * * Note that the symlink resolution is not *completely* iterative. * There is still a significant amount of tail- and mid- recursion in * the algorithm. Also, note that <fs>_readlink() is not used in * lookup_dentry(): lookup_dentry() on the result of <fs>_readlink() * may return different results than <fs>_follow_link(). Many virtual * filesystems (including /proc) exhibit this behavior. */ /* [24-Feb-97 T. Schoebel-Theuer] Side effects caused by new implementation: * New symlink semantics: when open() is called with flags O_CREAT | O_EXCL * and the name already exists in form of a symlink, try to create the new * name indicated by the symlink. The old code always complained that the * name already exists, due to not following the symlink even if its target * is nonexistent. The new semantics affects also mknod() and link() when * the name is a symlink pointing to a non-existent name. * * I don't know which semantics is the right one, since I have no access * to standards. But I found by trial that HP-UX 9.0 has the full "new" * semantics implemented, while SunOS 4.1.1 and Solaris (SunOS 5.4) have the * "old" one. Personally, I think the new semantics is much more logical. * Note that "ln old new" where "new" is a symlink pointing to a non-existing * file does succeed in both HP-UX and SunOs, but not in Solaris * and in the old Linux semantics. */ /* [16-Dec-97 Kevin Buhr] For security reasons, we change some symlink * semantics. See the comments in "open_namei" and "do_link" below. * * [10-Sep-98 Alan Modra] Another symlink change. */ /* [Feb-Apr 2000 AV] Complete rewrite. Rules for symlinks: * inside the path - always follow. * in the last component in creation/removal/renaming - never follow. * if LOOKUP_FOLLOW passed - follow. * if the pathname has trailing slashes - follow. * otherwise - don't follow. * (applied in that order). * * [Jun 2000 AV] Inconsistent behaviour of open() in case if flags==O_CREAT * restored for 2.4. This is the last surviving part of old 4.2BSD bug. * During the 2.4 we need to fix the userland stuff depending on it - * hopefully we will be able to get rid of that wart in 2.5. So far only * XEmacs seems to be relying on it... */ /* * [Sep 2001 AV] Single-semaphore locking scheme (kudos to David Holland) * implemented. Let's see if raised priority of ->s_vfs_rename_mutex gives * any extra contention... */ /* In order to reduce some races, while at the same time doing additional * checking and hopefully speeding things up, we copy filenames to the * kernel data space before using them.. * * POSIX.1 2.4: an empty pathname is invalid (ENOENT). * PATH_MAX includes the nul terminator --RR. */ #define EMBEDDED_NAME_MAX (PATH_MAX - offsetof(struct filename, iname)) struct filename * getname_flags(const char __user *filename, int flags, int *empty) { struct filename *result; char *kname; int len; result = audit_reusename(filename); if (result) return result; result = __getname(); if (unlikely(!result)) return ERR_PTR(-ENOMEM); /* * First, try to embed the struct filename inside the names_cache * allocation */ kname = (char *)result->iname; result->name = kname; len = strncpy_from_user(kname, filename, EMBEDDED_NAME_MAX); if (unlikely(len < 0)) { __putname(result); return ERR_PTR(len); } /* * Uh-oh. We have a name that's approaching PATH_MAX. Allocate a * separate struct filename so we can dedicate the entire * names_cache allocation for the pathname, and re-do the copy from * userland. */ if (unlikely(len == EMBEDDED_NAME_MAX)) { const size_t size = offsetof(struct filename, iname[1]); kname = (char *)result; /* * size is chosen that way we to guarantee that * result->iname[0] is within the same object and that * kname can't be equal to result->iname, no matter what. */ result = kzalloc(size, GFP_KERNEL); if (unlikely(!result)) { __putname(kname); return ERR_PTR(-ENOMEM); } result->name = kname; len = strncpy_from_user(kname, filename, PATH_MAX); if (unlikely(len < 0)) { __putname(kname); kfree(result); return ERR_PTR(len); } if (unlikely(len == PATH_MAX)) { __putname(kname); kfree(result); return ERR_PTR(-ENAMETOOLONG); } } result->refcnt = 1; /* The empty path is special. */ if (unlikely(!len)) { if (empty) *empty = 1; if (!(flags & LOOKUP_EMPTY)) { putname(result); return ERR_PTR(-ENOENT); } } result->uptr = filename; result->aname = NULL; audit_getname(result); return result; } struct filename * getname(const char __user * filename) { return getname_flags(filename, 0, NULL); } struct filename * getname_kernel(const char * filename) { struct filename *result; int len = strlen(filename) + 1; result = __getname(); if (unlikely(!result)) return ERR_PTR(-ENOMEM); if (len <= EMBEDDED_NAME_MAX) { result->name = (char *)result->iname; } else if (len <= PATH_MAX) { const size_t size = offsetof(struct filename, iname[1]); struct filename *tmp; tmp = kmalloc(size, GFP_KERNEL); if (unlikely(!tmp)) { __putname(result); return ERR_PTR(-ENOMEM); } tmp->name = (char *)result; result = tmp; } else { __putname(result); return ERR_PTR(-ENAMETOOLONG); } memcpy((char *)result->name, filename, len); result->uptr = NULL; result->aname = NULL; result->refcnt = 1; audit_getname(result); return result; } void putname(struct filename *name) { BUG_ON(name->refcnt <= 0); if (--name->refcnt > 0) return; if (name->name != name->iname) { __putname(name->name); kfree(name); } else __putname(name); } static int check_acl(struct inode *inode, int mask) { #ifdef CONFIG_FS_POSIX_ACL struct posix_acl *acl; if (mask & MAY_NOT_BLOCK) { acl = get_cached_acl_rcu(inode, ACL_TYPE_ACCESS); if (!acl) return -EAGAIN; /* no ->get_acl() calls in RCU mode... */ if (is_uncached_acl(acl)) return -ECHILD; return posix_acl_permission(inode, acl, mask); } acl = get_acl(inode, ACL_TYPE_ACCESS); if (IS_ERR(acl)) return PTR_ERR(acl); if (acl) { int error = posix_acl_permission(inode, acl, mask); posix_acl_release(acl); return error; } #endif return -EAGAIN; } /* * This does the basic UNIX permission checking. * * Note that the POSIX ACL check cares about the MAY_NOT_BLOCK bit, * for RCU walking. */ static int acl_permission_check(struct inode *inode, int mask) { unsigned int mode = inode->i_mode; /* Are we the owner? If so, ACL's don't matter */ if (likely(uid_eq(current_fsuid(), inode->i_uid))) { mask &= 7; mode >>= 6; return (mask & ~mode) ? -EACCES : 0; } /* Do we have ACL's? */ if (IS_POSIXACL(inode) && (mode & S_IRWXG)) { int error = check_acl(inode, mask); if (error != -EAGAIN) return error; } /* Only RWX matters for group/other mode bits */ mask &= 7; /* * Are the group permissions different from * the other permissions in the bits we care * about? Need to check group ownership if so. */ if (mask & (mode ^ (mode >> 3))) { if (in_group_p(inode->i_gid)) mode >>= 3; } /* Bits in 'mode' clear that we require? */ return (mask & ~mode) ? -EACCES : 0; } /** * generic_permission - check for access rights on a Posix-like filesystem * @inode: inode to check access rights for * @mask: right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC, * %MAY_NOT_BLOCK ...) * * Used to check for read/write/execute permissions on a file. * We use "fsuid" for this, letting us set arbitrary permissions * for filesystem access without changing the "normal" uids which * are used for other things. * * generic_permission is rcu-walk aware. It returns -ECHILD in case an rcu-walk * request cannot be satisfied (eg. requires blocking or too much complexity). * It would then be called again in ref-walk mode. */ int generic_permission(struct inode *inode, int mask) { int ret; /* * Do the basic permission checks. */ ret = acl_permission_check(inode, mask); if (ret != -EACCES) return ret; if (S_ISDIR(inode->i_mode)) { /* DACs are overridable for directories */ if (!(mask & MAY_WRITE)) if (capable_wrt_inode_uidgid(inode, CAP_DAC_READ_SEARCH)) return 0; if (capable_wrt_inode_uidgid(inode, CAP_DAC_OVERRIDE)) return 0; return -EACCES; } /* * Searching includes executable on directories, else just read. */ mask &= MAY_READ | MAY_WRITE | MAY_EXEC; if (mask == MAY_READ) if (capable_wrt_inode_uidgid(inode, CAP_DAC_READ_SEARCH)) return 0; /* * Read/write DACs are always overridable. * Executable DACs are overridable when there is * at least one exec bit set. */ if (!(mask & MAY_EXEC) || (inode->i_mode & S_IXUGO)) if (capable_wrt_inode_uidgid(inode, CAP_DAC_OVERRIDE)) return 0; return -EACCES; } EXPORT_SYMBOL(generic_permission); /* * We _really_ want to just do "generic_permission()" without * even looking at the inode->i_op values. So we keep a cache * flag in inode->i_opflags, that says "this has not special * permission function, use the fast case". */ static inline int do_inode_permission(struct inode *inode, int mask) { if (unlikely(!(inode->i_opflags & IOP_FASTPERM))) { if (likely(inode->i_op->permission)) return inode->i_op->permission(inode, mask); /* This gets set once for the inode lifetime */ spin_lock(&inode->i_lock); inode->i_opflags |= IOP_FASTPERM; spin_unlock(&inode->i_lock); } return generic_permission(inode, mask); } /** * sb_permission - Check superblock-level permissions * @sb: Superblock of inode to check permission on * @inode: Inode to check permission on * @mask: Right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC) * * Separate out file-system wide checks from inode-specific permission checks. */ static int sb_permission(struct super_block *sb, struct inode *inode, int mask) { if (unlikely(mask & MAY_WRITE)) { umode_t mode = inode->i_mode; /* Nobody gets write access to a read-only fs. */ if (sb_rdonly(sb) && (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))) return -EROFS; } return 0; } /** * inode_permission - Check for access rights to a given inode * @inode: Inode to check permission on * @mask: Right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC) * * Check for read/write/execute permissions on an inode. We use fs[ug]id for * this, letting us set arbitrary permissions for filesystem access without * changing the "normal" UIDs which are used for other things. * * When checking for MAY_APPEND, MAY_WRITE must also be set in @mask. */ int inode_permission(struct inode *inode, int mask) { int retval; retval = sb_permission(inode->i_sb, inode, mask); if (retval) return retval; if (unlikely(mask & MAY_WRITE)) { /* * Nobody gets write access to an immutable file. */ if (IS_IMMUTABLE(inode)) return -EPERM; /* * Updating mtime will likely cause i_uid and i_gid to be * written back improperly if their true value is unknown * to the vfs. */ if (HAS_UNMAPPED_ID(inode)) return -EACCES; } retval = do_inode_permission(inode, mask); if (retval) return retval; retval = devcgroup_inode_permission(inode, mask); if (retval) return retval; return security_inode_permission(inode, mask); } EXPORT_SYMBOL(inode_permission); /** * path_get - get a reference to a path * @path: path to get the reference to * * Given a path increment the reference count to the dentry and the vfsmount. */ void path_get(const struct path *path) { mntget(path->mnt); dget(path->dentry); } EXPORT_SYMBOL(path_get); /** * path_put - put a reference to a path * @path: path to put the reference to * * Given a path decrement the reference count to the dentry and the vfsmount. */ void path_put(const struct path *path) { dput(path->dentry); mntput(path->mnt); } EXPORT_SYMBOL(path_put); #define EMBEDDED_LEVELS 2 struct nameidata { struct path path; struct qstr last; struct path root; struct inode *inode; /* path.dentry.d_inode */ unsigned int flags; unsigned seq, m_seq, r_seq; int last_type; unsigned depth; int total_link_count; struct saved { struct path link; struct delayed_call done; const char *name; unsigned seq; } *stack, internal[EMBEDDED_LEVELS]; struct filename *name; struct nameidata *saved; unsigned root_seq; int dfd; kuid_t dir_uid; umode_t dir_mode; } __randomize_layout; static void set_nameidata(struct nameidata *p, int dfd, struct filename *name) { struct nameidata *old = current->nameidata; p->stack = p->internal; p->dfd = dfd; p->name = name; p->total_link_count = old ? old->total_link_count : 0; p->saved = old; current->nameidata = p; } static void restore_nameidata(void) { struct nameidata *now = current->nameidata, *old = now->saved; current->nameidata = old; if (old) old->total_link_count = now->total_link_count; if (now->stack != now->internal) kfree(now->stack); } static bool nd_alloc_stack(struct nameidata *nd) { struct saved *p; p= kmalloc_array(MAXSYMLINKS, sizeof(struct saved), nd->flags & LOOKUP_RCU ? GFP_ATOMIC : GFP_KERNEL); if (unlikely(!p)) return false; memcpy(p, nd->internal, sizeof(nd->internal)); nd->stack = p; return true; } /** * path_connected - Verify that a dentry is below mnt.mnt_root * * Rename can sometimes move a file or directory outside of a bind * mount, path_connected allows those cases to be detected. */ static bool path_connected(struct vfsmount *mnt, struct dentry *dentry) { struct super_block *sb = mnt->mnt_sb; /* Bind mounts can have disconnected paths */ if (mnt->mnt_root == sb->s_root) return true; return is_subdir(dentry, mnt->mnt_root); } static void drop_links(struct nameidata *nd) { int i = nd->depth; while (i--) { struct saved *last = nd->stack + i; do_delayed_call(&last->done); clear_delayed_call(&last->done); } } static void terminate_walk(struct nameidata *nd) { drop_links(nd); if (!(nd->flags & LOOKUP_RCU)) { int i; path_put(&nd->path); for (i = 0; i < nd->depth; i++) path_put(&nd->stack[i].link); if (nd->flags & LOOKUP_ROOT_GRABBED) { path_put(&nd->root); nd->flags &= ~LOOKUP_ROOT_GRABBED; } } else { nd->flags &= ~LOOKUP_RCU; rcu_read_unlock(); } nd->depth = 0; } /* path_put is needed afterwards regardless of success or failure */ static bool __legitimize_path(struct path *path, unsigned seq, unsigned mseq) { int res = __legitimize_mnt(path->mnt, mseq); if (unlikely(res)) { if (res > 0) path->mnt = NULL; path->dentry = NULL; return false; } if (unlikely(!lockref_get_not_dead(&path->dentry->d_lockref))) { path->dentry = NULL; return false; } return !read_seqcount_retry(&path->dentry->d_seq, seq); } static inline bool legitimize_path(struct nameidata *nd, struct path *path, unsigned seq) { return __legitimize_path(path, seq, nd->m_seq); } static bool legitimize_links(struct nameidata *nd) { int i; for (i = 0; i < nd->depth; i++) { struct saved *last = nd->stack + i; if (unlikely(!legitimize_path(nd, &last->link, last->seq))) { drop_links(nd); nd->depth = i + 1; return false; } } return true; } static bool legitimize_root(struct nameidata *nd) { /* * For scoped-lookups (where nd->root has been zeroed), we need to * restart the whole lookup from scratch -- because set_root() is wrong * for these lookups (nd->dfd is the root, not the filesystem root). */ if (!nd->root.mnt && (nd->flags & LOOKUP_IS_SCOPED)) return false; /* Nothing to do if nd->root is zero or is managed by the VFS user. */ if (!nd->root.mnt || (nd->flags & LOOKUP_ROOT)) return true; nd->flags |= LOOKUP_ROOT_GRABBED; return legitimize_path(nd, &nd->root, nd->root_seq); } /* * Path walking has 2 modes, rcu-walk and ref-walk (see * Documentation/filesystems/path-lookup.txt). In situations when we can't * continue in RCU mode, we attempt to drop out of rcu-walk mode and grab * normal reference counts on dentries and vfsmounts to transition to ref-walk * mode. Refcounts are grabbed at the last known good point before rcu-walk * got stuck, so ref-walk may continue from there. If this is not successful * (eg. a seqcount has changed), then failure is returned and it's up to caller * to restart the path walk from the beginning in ref-walk mode. */ /** * try_to_unlazy - try to switch to ref-walk mode. * @nd: nameidata pathwalk data * Returns: true on success, false on failure * * try_to_unlazy attempts to legitimize the current nd->path and nd->root * for ref-walk mode. * Must be called from rcu-walk context. * Nothing should touch nameidata between try_to_unlazy() failure and * terminate_walk(). */ static bool try_to_unlazy(struct nameidata *nd) { struct dentry *parent = nd->path.dentry; BUG_ON(!(nd->flags & LOOKUP_RCU)); nd->flags &= ~LOOKUP_RCU; if (unlikely(!legitimize_links(nd))) goto out1; if (unlikely(!legitimize_path(nd, &nd->path, nd->seq))) goto out; if (unlikely(!legitimize_root(nd))) goto out; rcu_read_unlock(); BUG_ON(nd->inode != parent->d_inode); return true; out1: nd->path.mnt = NULL; nd->path.dentry = NULL; out: rcu_read_unlock(); return false; } /** * unlazy_child - try to switch to ref-walk mode. * @nd: nameidata pathwalk data * @dentry: child of nd->path.dentry * @seq: seq number to check dentry against * Returns: 0 on success, -ECHILD on failure * * unlazy_child attempts to legitimize the current nd->path, nd->root and dentry * for ref-walk mode. @dentry must be a path found by a do_lookup call on * @nd. Must be called from rcu-walk context. * Nothing should touch nameidata between unlazy_child() failure and * terminate_walk(). */ static int unlazy_child(struct nameidata *nd, struct dentry *dentry, unsigned seq) { BUG_ON(!(nd->flags & LOOKUP_RCU)); nd->flags &= ~LOOKUP_RCU; if (unlikely(!legitimize_links(nd))) goto out2; if (unlikely(!legitimize_mnt(nd->path.mnt, nd->m_seq))) goto out2; if (unlikely(!lockref_get_not_dead(&nd->path.dentry->d_lockref))) goto out1; /* * We need to move both the parent and the dentry from the RCU domain * to be properly refcounted. And the sequence number in the dentry * validates *both* dentry counters, since we checked the sequence * number of the parent after we got the child sequence number. So we * know the parent must still be valid if the child sequence number is */ if (unlikely(!lockref_get_not_dead(&dentry->d_lockref))) goto out; if (unlikely(read_seqcount_retry(&dentry->d_seq, seq))) goto out_dput; /* * Sequence counts matched. Now make sure that the root is * still valid and get it if required. */ if (unlikely(!legitimize_root(nd))) goto out_dput; rcu_read_unlock(); return 0; out2: nd->path.mnt = NULL; out1: nd->path.dentry = NULL; out: rcu_read_unlock(); return -ECHILD; out_dput: rcu_read_unlock(); dput(dentry); return -ECHILD; } static inline int d_revalidate(struct dentry *dentry, unsigned int flags) { if (unlikely(dentry->d_flags & DCACHE_OP_REVALIDATE)) return dentry->d_op->d_revalidate(dentry, flags); else return 1; } /** * complete_walk - successful completion of path walk * @nd: pointer nameidata * * If we had been in RCU mode, drop out of it and legitimize nd->path. * Revalidate the final result, unless we'd already done that during * the path walk or the filesystem doesn't ask for it. Return 0 on * success, -error on failure. In case of failure caller does not * need to drop nd->path. */ static int complete_walk(struct nameidata *nd) { struct dentry *dentry = nd->path.dentry; int status; if (nd->flags & LOOKUP_RCU) { /* * We don't want to zero nd->root for scoped-lookups or * externally-managed nd->root. */ if (!(nd->flags & (LOOKUP_ROOT | LOOKUP_IS_SCOPED))) nd->root.mnt = NULL; if (!try_to_unlazy(nd)) return -ECHILD; } if (unlikely(nd->flags & LOOKUP_IS_SCOPED)) { /* * While the guarantee of LOOKUP_IS_SCOPED is (roughly) "don't * ever step outside the root during lookup" and should already * be guaranteed by the rest of namei, we want to avoid a namei * BUG resulting in userspace being given a path that was not * scoped within the root at some point during the lookup. * * So, do a final sanity-check to make sure that in the * worst-case scenario (a complete bypass of LOOKUP_IS_SCOPED) * we won't silently return an fd completely outside of the * requested root to userspace. * * Userspace could move the path outside the root after this * check, but as discussed elsewhere this is not a concern (the * resolved file was inside the root at some point). */ if (!path_is_under(&nd->path, &nd->root)) return -EXDEV; } if (likely(!(nd->flags & LOOKUP_JUMPED))) return 0; if (likely(!(dentry->d_flags & DCACHE_OP_WEAK_REVALIDATE))) return 0; status = dentry->d_op->d_weak_revalidate(dentry, nd->flags); if (status > 0) return 0; if (!status) status = -ESTALE; return status; } static int set_root(struct nameidata *nd) { struct fs_struct *fs = current->fs; /* * Jumping to the real root in a scoped-lookup is a BUG in namei, but we * still have to ensure it doesn't happen because it will cause a breakout * from the dirfd. */ if (WARN_ON(nd->flags & LOOKUP_IS_SCOPED)) return -ENOTRECOVERABLE; if (nd->flags & LOOKUP_RCU) { unsigned seq; do { seq = read_seqcount_begin(&fs->seq); nd->root = fs->root; nd->root_seq = __read_seqcount_begin(&nd->root.dentry->d_seq); } while (read_seqcount_retry(&fs->seq, seq)); } else { get_fs_root(fs, &nd->root); nd->flags |= LOOKUP_ROOT_GRABBED; } return 0; } static int nd_jump_root(struct nameidata *nd) { if (unlikely(nd->flags & LOOKUP_BENEATH)) return -EXDEV; if (unlikely(nd->flags & LOOKUP_NO_XDEV)) { /* Absolute path arguments to path_init() are allowed. */ if (nd->path.mnt != NULL && nd->path.mnt != nd->root.mnt) return -EXDEV; } if (!nd->root.mnt) { int error = set_root(nd); if (error) return error; } if (nd->flags & LOOKUP_RCU) { struct dentry *d; nd->path = nd->root; d = nd->path.dentry; nd->inode = d->d_inode; nd->seq = nd->root_seq; if (unlikely(read_seqcount_retry(&d->d_seq, nd->seq))) return -ECHILD; } else { path_put(&nd->path); nd->path = nd->root; path_get(&nd->path); nd->inode = nd->path.dentry->d_inode; } nd->flags |= LOOKUP_JUMPED; return 0; } /* * Helper to directly jump to a known parsed path from ->get_link, * caller must have taken a reference to path beforehand. */ int nd_jump_link(struct path *path) { int error = -ELOOP; struct nameidata *nd = current->nameidata; if (unlikely(nd->flags & LOOKUP_NO_MAGICLINKS)) goto err; error = -EXDEV; if (unlikely(nd->flags & LOOKUP_NO_XDEV)) { if (nd->path.mnt != path->mnt) goto err; } /* Not currently safe for scoped-lookups. */ if (unlikely(nd->flags & LOOKUP_IS_SCOPED)) goto err; path_put(&nd->path); nd->path = *path; nd->inode = nd->path.dentry->d_inode; nd->flags |= LOOKUP_JUMPED; return 0; err: path_put(path); return error; } static inline void put_link(struct nameidata *nd) { struct saved *last = nd->stack + --nd->depth; do_delayed_call(&last->done); if (!(nd->flags & LOOKUP_RCU)) path_put(&last->link); } int sysctl_protected_symlinks __read_mostly = 0; int sysctl_protected_hardlinks __read_mostly = 0; int sysctl_protected_fifos __read_mostly; int sysctl_protected_regular __read_mostly; /** * may_follow_link - Check symlink following for unsafe situations * @nd: nameidata pathwalk data * * In the case of the sysctl_protected_symlinks sysctl being enabled, * CAP_DAC_OVERRIDE needs to be specifically ignored if the symlink is * in a sticky world-writable directory. This is to protect privileged * processes from failing races against path names that may change out * from under them by way of other users creating malicious symlinks. * It will permit symlinks to be followed only when outside a sticky * world-writable directory, or when the uid of the symlink and follower * match, or when the directory owner matches the symlink's owner. * * Returns 0 if following the symlink is allowed, -ve on error. */ static inline int may_follow_link(struct nameidata *nd, const struct inode *inode) { if (!sysctl_protected_symlinks) return 0; /* Allowed if owner and follower match. */ if (uid_eq(current_cred()->fsuid, inode->i_uid)) return 0; /* Allowed if parent directory not sticky and world-writable. */ if ((nd->dir_mode & (S_ISVTX|S_IWOTH)) != (S_ISVTX|S_IWOTH)) return 0; /* Allowed if parent directory and link owner match. */ if (uid_valid(nd->dir_uid) && uid_eq(nd->dir_uid, inode->i_uid)) return 0; if (nd->flags & LOOKUP_RCU) return -ECHILD; audit_inode(nd->name, nd->stack[0].link.dentry, 0); audit_log_path_denied(AUDIT_ANOM_LINK, "follow_link"); return -EACCES; } /** * safe_hardlink_source - Check for safe hardlink conditions * @inode: the source inode to hardlink from * * Return false if at least one of the following conditions: * - inode is not a regular file * - inode is setuid * - inode is setgid and group-exec * - access failure for read and write * * Otherwise returns true. */ static bool safe_hardlink_source(struct inode *inode) { umode_t mode = inode->i_mode; /* Special files should not get pinned to the filesystem. */ if (!S_ISREG(mode)) return false; /* Setuid files should not get pinned to the filesystem. */ if (mode & S_ISUID) return false; /* Executable setgid files should not get pinned to the filesystem. */ if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) return false; /* Hardlinking to unreadable or unwritable sources is dangerous. */ if (inode_permission(inode, MAY_READ | MAY_WRITE)) return false; return true; } /** * may_linkat - Check permissions for creating a hardlink * @link: the source to hardlink from * * Block hardlink when all of: * - sysctl_protected_hardlinks enabled * - fsuid does not match inode * - hardlink source is unsafe (see safe_hardlink_source() above) * - not CAP_FOWNER in a namespace with the inode owner uid mapped * * Returns 0 if successful, -ve on error. */ int may_linkat(struct path *link) { struct inode *inode = link->dentry->d_inode; /* Inode writeback is not safe when the uid or gid are invalid. */ if (!uid_valid(inode->i_uid) || !gid_valid(inode->i_gid)) return -EOVERFLOW; if (!sysctl_protected_hardlinks) return 0; /* Source inode owner (or CAP_FOWNER) can hardlink all they like, * otherwise, it must be a safe source. */ if (safe_hardlink_source(inode) || inode_owner_or_capable(inode)) return 0; audit_log_path_denied(AUDIT_ANOM_LINK, "linkat"); return -EPERM; } /** * may_create_in_sticky - Check whether an O_CREAT open in a sticky directory * should be allowed, or not, on files that already * exist. * @dir_mode: mode bits of directory * @dir_uid: owner of directory * @inode: the inode of the file to open * * Block an O_CREAT open of a FIFO (or a regular file) when: * - sysctl_protected_fifos (or sysctl_protected_regular) is enabled * - the file already exists * - we are in a sticky directory * - we don't own the file * - the owner of the directory doesn't own the file * - the directory is world writable * If the sysctl_protected_fifos (or sysctl_protected_regular) is set to 2 * the directory doesn't have to be world writable: being group writable will * be enough. * * Returns 0 if the open is allowed, -ve on error. */ static int may_create_in_sticky(umode_t dir_mode, kuid_t dir_uid, struct inode * const inode) { if ((!sysctl_protected_fifos && S_ISFIFO(inode->i_mode)) || (!sysctl_protected_regular && S_ISREG(inode->i_mode)) || likely(!(dir_mode & S_ISVTX)) || uid_eq(inode->i_uid, dir_uid) || uid_eq(current_fsuid(), inode->i_uid)) return 0; if (likely(dir_mode & 0002) || (dir_mode & 0020 && ((sysctl_protected_fifos >= 2 && S_ISFIFO(inode->i_mode)) || (sysctl_protected_regular >= 2 && S_ISREG(inode->i_mode))))) { const char *operation = S_ISFIFO(inode->i_mode) ? "sticky_create_fifo" : "sticky_create_regular"; audit_log_path_denied(AUDIT_ANOM_CREAT, operation); return -EACCES; } return 0; } /* * follow_up - Find the mountpoint of path's vfsmount * * Given a path, find the mountpoint of its source file system. * Replace @path with the path of the mountpoint in the parent mount. * Up is towards /. * * Return 1 if we went up a level and 0 if we were already at the * root. */ int follow_up(struct path *path) { struct mount *mnt = real_mount(path->mnt); struct mount *parent; struct dentry *mountpoint; read_seqlock_excl(&mount_lock); parent = mnt->mnt_parent; if (parent == mnt) { read_sequnlock_excl(&mount_lock); return 0; } mntget(&parent->mnt); mountpoint = dget(mnt->mnt_mountpoint); read_sequnlock_excl(&mount_lock); dput(path->dentry); path->dentry = mountpoint; mntput(path->mnt); path->mnt = &parent->mnt; return 1; } EXPORT_SYMBOL(follow_up); static bool choose_mountpoint_rcu(struct mount *m, const struct path *root, struct path *path, unsigned *seqp) { while (mnt_has_parent(m)) { struct dentry *mountpoint = m->mnt_mountpoint; m = m->mnt_parent; if (unlikely(root->dentry == mountpoint && root->mnt == &m->mnt)) break; if (mountpoint != m->mnt.mnt_root) { path->mnt = &m->mnt; path->dentry = mountpoint; *seqp = read_seqcount_begin(&mountpoint->d_seq); return true; } } return false; } static bool choose_mountpoint(struct mount *m, const struct path *root, struct path *path) { bool found; rcu_read_lock(); while (1) { unsigned seq, mseq = read_seqbegin(&mount_lock); found = choose_mountpoint_rcu(m, root, path, &seq); if (unlikely(!found)) { if (!read_seqretry(&mount_lock, mseq)) break; } else { if (likely(__legitimize_path(path, seq, mseq))) break; rcu_read_unlock(); path_put(path); rcu_read_lock(); } } rcu_read_unlock(); return found; } /* * Perform an automount * - return -EISDIR to tell follow_managed() to stop and return the path we * were called with. */ static int follow_automount(struct path *path, int *count, unsigned lookup_flags) { struct dentry *dentry = path->dentry; /* We don't want to mount if someone's just doing a stat - * unless they're stat'ing a directory and appended a '/' to * the name. * * We do, however, want to mount if someone wants to open or * create a file of any type under the mountpoint, wants to * traverse through the mountpoint or wants to open the * mounted directory. Also, autofs may mark negative dentries * as being automount points. These will need the attentions * of the daemon to instantiate them before they can be used. */ if (!(lookup_flags & (LOOKUP_PARENT | LOOKUP_DIRECTORY | LOOKUP_OPEN | LOOKUP_CREATE | LOOKUP_AUTOMOUNT)) && dentry->d_inode) return -EISDIR; if (count && (*count)++ >= MAXSYMLINKS) return -ELOOP; return finish_automount(dentry->d_op->d_automount(path), path); } /* * mount traversal - out-of-line part. One note on ->d_flags accesses - * dentries are pinned but not locked here, so negative dentry can go * positive right under us. Use of smp_load_acquire() provides a barrier * sufficient for ->d_inode and ->d_flags consistency. */ static int __traverse_mounts(struct path *path, unsigned flags, bool *jumped, int *count, unsigned lookup_flags) { struct vfsmount *mnt = path->mnt; bool need_mntput = false; int ret = 0; while (flags & DCACHE_MANAGED_DENTRY) { /* Allow the filesystem to manage the transit without i_mutex * being held. */ if (flags & DCACHE_MANAGE_TRANSIT) { ret = path->dentry->d_op->d_manage(path, false); flags = smp_load_acquire(&path->dentry->d_flags); if (ret < 0) break; } if (flags & DCACHE_MOUNTED) { // something's mounted on it.. struct vfsmount *mounted = lookup_mnt(path); if (mounted) { // ... in our namespace dput(path->dentry); if (need_mntput) mntput(path->mnt); path->mnt = mounted; path->dentry = dget(mounted->mnt_root); // here we know it's positive flags = path->dentry->d_flags; need_mntput = true; continue; } } if (!(flags & DCACHE_NEED_AUTOMOUNT)) break; // uncovered automount point ret = follow_automount(path, count, lookup_flags); flags = smp_load_acquire(&path->dentry->d_flags); if (ret < 0) break; } if (ret == -EISDIR) ret = 0; // possible if you race with several mount --move if (need_mntput && path->mnt == mnt) mntput(path->mnt); if (!ret && unlikely(d_flags_negative(flags))) ret = -ENOENT; *jumped = need_mntput; return ret; } static inline int traverse_mounts(struct path *path, bool *jumped, int *count, unsigned lookup_flags) { unsigned flags = smp_load_acquire(&path->dentry->d_flags); /* fastpath */ if (likely(!(flags & DCACHE_MANAGED_DENTRY))) { *jumped = false; if (unlikely(d_flags_negative(flags))) return -ENOENT; return 0; } return __traverse_mounts(path, flags, jumped, count, lookup_flags); } int follow_down_one(struct path *path) { struct vfsmount *mounted; mounted = lookup_mnt(path); if (mounted) { dput(path->dentry); mntput(path->mnt); path->mnt = mounted; path->dentry = dget(mounted->mnt_root); return 1; } return 0; } EXPORT_SYMBOL(follow_down_one); /* * Follow down to the covering mount currently visible to userspace. At each * point, the filesystem owning that dentry may be queried as to whether the * caller is permitted to proceed or not. */ int follow_down(struct path *path) { struct vfsmount *mnt = path->mnt; bool jumped; int ret = traverse_mounts(path, &jumped, NULL, 0); if (path->mnt != mnt) mntput(mnt); return ret; } EXPORT_SYMBOL(follow_down); /* * Try to skip to top of mountpoint pile in rcuwalk mode. Fail if * we meet a managed dentry that would need blocking. */ static bool __follow_mount_rcu(struct nameidata *nd, struct path *path, struct inode **inode, unsigned *seqp) { struct dentry *dentry = path->dentry; unsigned int flags = dentry->d_flags; if (likely(!(flags & DCACHE_MANAGED_DENTRY))) return true; if (unlikely(nd->flags & LOOKUP_NO_XDEV)) return false; for (;;) { /* * Don't forget we might have a non-mountpoint managed dentry * that wants to block transit. */ if (unlikely(flags & DCACHE_MANAGE_TRANSIT)) { int res = dentry->d_op->d_manage(path, true); if (res) return res == -EISDIR; flags = dentry->d_flags; } if (flags & DCACHE_MOUNTED) { struct mount *mounted = __lookup_mnt(path->mnt, dentry); if (mounted) { path->mnt = &mounted->mnt; dentry = path->dentry = mounted->mnt.mnt_root; nd->flags |= LOOKUP_JUMPED; *seqp = read_seqcount_begin(&dentry->d_seq); *inode = dentry->d_inode; /* * We don't need to re-check ->d_seq after this * ->d_inode read - there will be an RCU delay * between mount hash removal and ->mnt_root * becoming unpinned. */ flags = dentry->d_flags; continue; } if (read_seqretry(&mount_lock, nd->m_seq)) return false; } return !(flags & DCACHE_NEED_AUTOMOUNT); } } static inline int handle_mounts(struct nameidata *nd, struct dentry *dentry, struct path *path, struct inode **inode, unsigned int *seqp) { bool jumped; int ret; path->mnt = nd->path.mnt; path->dentry = dentry; if (nd->flags & LOOKUP_RCU) { unsigned int seq = *seqp; if (unlikely(!*inode)) return -ENOENT; if (likely(__follow_mount_rcu(nd, path, inode, seqp))) return 0; if (unlazy_child(nd, dentry, seq)) return -ECHILD; // *path might've been clobbered by __follow_mount_rcu() path->mnt = nd->path.mnt; path->dentry = dentry; } ret = traverse_mounts(path, &jumped, &nd->total_link_count, nd->flags); if (jumped) { if (unlikely(nd->flags & LOOKUP_NO_XDEV)) ret = -EXDEV; else nd->flags |= LOOKUP_JUMPED; } if (unlikely(ret)) { dput(path->dentry); if (path->mnt != nd->path.mnt) mntput(path->mnt); } else { *inode = d_backing_inode(path->dentry); *seqp = 0; /* out of RCU mode, so the value doesn't matter */ } return ret; } /* * This looks up the name in dcache and possibly revalidates the found dentry. * NULL is returned if the dentry does not exist in the cache. */ static struct dentry *lookup_dcache(const struct qstr *name, struct dentry *dir, unsigned int flags) { struct dentry *dentry = d_lookup(dir, name); if (dentry) { int error = d_revalidate(dentry, flags); if (unlikely(error <= 0)) { if (!error) d_invalidate(dentry); dput(dentry); return ERR_PTR(error); } } return dentry; } /* * Parent directory has inode locked exclusive. This is one * and only case when ->lookup() gets called on non in-lookup * dentries - as the matter of fact, this only gets called * when directory is guaranteed to have no in-lookup children * at all. */ static struct dentry *__lookup_hash(const struct qstr *name, struct dentry *base, unsigned int flags) { struct dentry *dentry = lookup_dcache(name, base, flags); struct dentry *old; struct inode *dir = base->d_inode; if (dentry) return dentry; /* Don't create child dentry for a dead directory. */ if (unlikely(IS_DEADDIR(dir))) return ERR_PTR(-ENOENT); dentry = d_alloc(base, name); if (unlikely(!dentry)) return ERR_PTR(-ENOMEM); old = dir->i_op->lookup(dir, dentry, flags); if (unlikely(old)) { dput(dentry); dentry = old; } return dentry; } static struct dentry *lookup_fast(struct nameidata *nd, struct inode **inode, unsigned *seqp) { struct dentry *dentry, *parent = nd->path.dentry; int status = 1; /* * Rename seqlock is not required here because in the off chance * of a false negative due to a concurrent rename, the caller is * going to fall back to non-racy lookup. */ if (nd->flags & LOOKUP_RCU) { unsigned seq; dentry = __d_lookup_rcu(parent, &nd->last, &seq); if (unlikely(!dentry)) { if (!try_to_unlazy(nd)) return ERR_PTR(-ECHILD); return NULL; } /* * This sequence count validates that the inode matches * the dentry name information from lookup. */ *inode = d_backing_inode(dentry); if (unlikely(read_seqcount_retry(&dentry->d_seq, seq))) return ERR_PTR(-ECHILD); /* * This sequence count validates that the parent had no * changes while we did the lookup of the dentry above. * * The memory barrier in read_seqcount_begin of child is * enough, we can use __read_seqcount_retry here. */ if (unlikely(__read_seqcount_retry(&parent->d_seq, nd->seq))) return ERR_PTR(-ECHILD); *seqp = seq; status = d_revalidate(dentry, nd->flags); if (likely(status > 0)) return dentry; if (unlazy_child(nd, dentry, seq)) return ERR_PTR(-ECHILD); if (unlikely(status == -ECHILD)) /* we'd been told to redo it in non-rcu mode */ status = d_revalidate(dentry, nd->flags); } else { dentry = __d_lookup(parent, &nd->last); if (unlikely(!dentry)) return NULL; status = d_revalidate(dentry, nd->flags); } if (unlikely(status <= 0)) { if (!status) d_invalidate(dentry); dput(dentry); return ERR_PTR(status); } return dentry; } /* Fast lookup failed, do it the slow way */ static struct dentry *__lookup_slow(const struct qstr *name, struct dentry *dir, unsigned int flags) { struct dentry *dentry, *old; struct inode *inode = dir->d_inode; DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq); /* Don't go there if it's already dead */ if (unlikely(IS_DEADDIR(inode))) return ERR_PTR(-ENOENT); again: dentry = d_alloc_parallel(dir, name, &wq); if (IS_ERR(dentry)) return dentry; if (unlikely(!d_in_lookup(dentry))) { int error = d_revalidate(dentry, flags); if (unlikely(error <= 0)) { if (!error) { d_invalidate(dentry); dput(dentry); goto again; } dput(dentry); dentry = ERR_PTR(error); } } else { old = inode->i_op->lookup(inode, dentry, flags); d_lookup_done(dentry); if (unlikely(old)) { dput(dentry); dentry = old; } } return dentry; } static struct dentry *lookup_slow(const struct qstr *name, struct dentry *dir, unsigned int flags) { struct inode *inode = dir->d_inode; struct dentry *res; inode_lock_shared(inode); res = __lookup_slow(name, dir, flags); inode_unlock_shared(inode); return res; } static inline int may_lookup(struct nameidata *nd) { if (nd->flags & LOOKUP_RCU) { int err = inode_permission(nd->inode, MAY_EXEC|MAY_NOT_BLOCK); if (err != -ECHILD || !try_to_unlazy(nd)) return err; } return inode_permission(nd->inode, MAY_EXEC); } static int reserve_stack(struct nameidata *nd, struct path *link, unsigned seq) { if (unlikely(nd->total_link_count++ >= MAXSYMLINKS)) return -ELOOP; if (likely(nd->depth != EMBEDDED_LEVELS)) return 0; if (likely(nd->stack != nd->internal)) return 0; if (likely(nd_alloc_stack(nd))) return 0; if (nd->flags & LOOKUP_RCU) { // we need to grab link before we do unlazy. And we can't skip // unlazy even if we fail to grab the link - cleanup needs it bool grabbed_link = legitimize_path(nd, link, seq); if (!try_to_unlazy(nd) != 0 || !grabbed_link) return -ECHILD; if (nd_alloc_stack(nd)) return 0; } return -ENOMEM; } enum {WALK_TRAILING = 1, WALK_MORE = 2, WALK_NOFOLLOW = 4}; static const char *pick_link(struct nameidata *nd, struct path *link, struct inode *inode, unsigned seq, int flags) { struct saved *last; const char *res; int error = reserve_stack(nd, link, seq); if (unlikely(error)) { if (!(nd->flags & LOOKUP_RCU)) path_put(link); return ERR_PTR(error); } last = nd->stack + nd->depth++; last->link = *link; clear_delayed_call(&last->done); last->seq = seq; if (flags & WALK_TRAILING) { error = may_follow_link(nd, inode); if (unlikely(error)) return ERR_PTR(error); } if (unlikely(nd->flags & LOOKUP_NO_SYMLINKS) || unlikely(link->mnt->mnt_flags & MNT_NOSYMFOLLOW)) return ERR_PTR(-ELOOP); if (!(nd->flags & LOOKUP_RCU)) { touch_atime(&last->link); cond_resched(); } else if (atime_needs_update(&last->link, inode)) { if (!try_to_unlazy(nd)) return ERR_PTR(-ECHILD); touch_atime(&last->link); } error = security_inode_follow_link(link->dentry, inode, nd->flags & LOOKUP_RCU); if (unlikely(error)) return ERR_PTR(error); res = READ_ONCE(inode->i_link); if (!res) { const char * (*get)(struct dentry *, struct inode *, struct delayed_call *); get = inode->i_op->get_link; if (nd->flags & LOOKUP_RCU) { res = get(NULL, inode, &last->done); if (res == ERR_PTR(-ECHILD) && try_to_unlazy(nd)) res = get(link->dentry, inode, &last->done); } else { res = get(link->dentry, inode, &last->done); } if (!res) goto all_done; if (IS_ERR(res)) return res; } if (*res == '/') { error = nd_jump_root(nd); if (unlikely(error)) return ERR_PTR(error); while (unlikely(*++res == '/')) ; } if (*res) return res; all_done: // pure jump put_link(nd); return NULL; } /* * Do we need to follow links? We _really_ want to be able * to do this check without having to look at inode->i_op, * so we keep a cache of "no, this doesn't need follow_link" * for the common case. */ static const char *step_into(struct nameidata *nd, int flags, struct dentry *dentry, struct inode *inode, unsigned seq) { struct path path; int err = handle_mounts(nd, dentry, &path, &inode, &seq); if (err < 0) return ERR_PTR(err); if (likely(!d_is_symlink(path.dentry)) || ((flags & WALK_TRAILING) && !(nd->flags & LOOKUP_FOLLOW)) || (flags & WALK_NOFOLLOW)) { /* not a symlink or should not follow */ if (!(nd->flags & LOOKUP_RCU)) { dput(nd->path.dentry); if (nd->path.mnt != path.mnt) mntput(nd->path.mnt); } nd->path = path; nd->inode = inode; nd->seq = seq; return NULL; } if (nd->flags & LOOKUP_RCU) { /* make sure that d_is_symlink above matches inode */ if (read_seqcount_retry(&path.dentry->d_seq, seq)) return ERR_PTR(-ECHILD); } else { if (path.mnt == nd->path.mnt) mntget(path.mnt); } return pick_link(nd, &path, inode, seq, flags); } static struct dentry *follow_dotdot_rcu(struct nameidata *nd, struct inode **inodep, unsigned *seqp) { struct dentry *parent, *old; if (path_equal(&nd->path, &nd->root)) goto in_root; if (unlikely(nd->path.dentry == nd->path.mnt->mnt_root)) { struct path path; unsigned seq; if (!choose_mountpoint_rcu(real_mount(nd->path.mnt), &nd->root, &path, &seq)) goto in_root; if (unlikely(nd->flags & LOOKUP_NO_XDEV)) return ERR_PTR(-ECHILD); nd->path = path; nd->inode = path.dentry->d_inode; nd->seq = seq; if (unlikely(read_seqretry(&mount_lock, nd->m_seq))) return ERR_PTR(-ECHILD); /* we know that mountpoint was pinned */ } old = nd->path.dentry; parent = old->d_parent; *inodep = parent->d_inode; *seqp = read_seqcount_begin(&parent->d_seq); if (unlikely(read_seqcount_retry(&old->d_seq, nd->seq))) return ERR_PTR(-ECHILD); if (unlikely(!path_connected(nd->path.mnt, parent))) return ERR_PTR(-ECHILD); return parent; in_root: if (unlikely(read_seqretry(&mount_lock, nd->m_seq))) return ERR_PTR(-ECHILD); if (unlikely(nd->flags & LOOKUP_BENEATH)) return ERR_PTR(-ECHILD); return NULL; } static struct dentry *follow_dotdot(struct nameidata *nd, struct inode **inodep, unsigned *seqp) { struct dentry *parent; if (path_equal(&nd->path, &nd->root)) goto in_root; if (unlikely(nd->path.dentry == nd->path.mnt->mnt_root)) { struct path path; if (!choose_mountpoint(real_mount(nd->path.mnt), &nd->root, &path)) goto in_root; path_put(&nd->path); nd->path = path; nd->inode = path.dentry->d_inode; if (unlikely(nd->flags & LOOKUP_NO_XDEV)) return ERR_PTR(-EXDEV); } /* rare case of legitimate dget_parent()... */ parent = dget_parent(nd->path.dentry); if (unlikely(!path_connected(nd->path.mnt, parent))) { dput(parent); return ERR_PTR(-ENOENT); } *seqp = 0; *inodep = parent->d_inode; return parent; in_root: if (unlikely(nd->flags & LOOKUP_BENEATH)) return ERR_PTR(-EXDEV); dget(nd->path.dentry); return NULL; } static const char *handle_dots(struct nameidata *nd, int type) { if (type == LAST_DOTDOT) { const char *error = NULL; struct dentry *parent; struct inode *inode; unsigned seq; if (!nd->root.mnt) { error = ERR_PTR(set_root(nd)); if (error) return error; } if (nd->flags & LOOKUP_RCU) parent = follow_dotdot_rcu(nd, &inode, &seq); else parent = follow_dotdot(nd, &inode, &seq); if (IS_ERR(parent)) return ERR_CAST(parent); if (unlikely(!parent)) error = step_into(nd, WALK_NOFOLLOW, nd->path.dentry, nd->inode, nd->seq); else error = step_into(nd, WALK_NOFOLLOW, parent, inode, seq); if (unlikely(error)) return error; if (unlikely(nd->flags & LOOKUP_IS_SCOPED)) { /* * If there was a racing rename or mount along our * path, then we can't be sure that ".." hasn't jumped * above nd->root (and so userspace should retry or use * some fallback). */ smp_rmb(); if (unlikely(__read_seqcount_retry(&mount_lock.seqcount, nd->m_seq))) return ERR_PTR(-EAGAIN); if (unlikely(__read_seqcount_retry(&rename_lock.seqcount, nd->r_seq))) return ERR_PTR(-EAGAIN); } } return NULL; } static const char *walk_component(struct nameidata *nd, int flags) { struct dentry *dentry; struct inode *inode; unsigned seq; /* * "." and ".." are special - ".." especially so because it has * to be able to know about the current root directory and * parent relationships. */ if (unlikely(nd->last_type != LAST_NORM)) { if (!(flags & WALK_MORE) && nd->depth) put_link(nd); return handle_dots(nd, nd->last_type); } dentry = lookup_fast(nd, &inode, &seq); if (IS_ERR(dentry)) return ERR_CAST(dentry); if (unlikely(!dentry)) { dentry = lookup_slow(&nd->last, nd->path.dentry, nd->flags); if (IS_ERR(dentry)) return ERR_CAST(dentry); } if (!(flags & WALK_MORE) && nd->depth) put_link(nd); return step_into(nd, flags, dentry, inode, seq); } /* * We can do the critical dentry name comparison and hashing * operations one word at a time, but we are limited to: * * - Architectures with fast unaligned word accesses. We could * do a "get_unaligned()" if this helps and is sufficiently * fast. * * - non-CONFIG_DEBUG_PAGEALLOC configurations (so that we * do not trap on the (extremely unlikely) case of a page * crossing operation. * * - Furthermore, we need an efficient 64-bit compile for the * 64-bit case in order to generate the "number of bytes in * the final mask". Again, that could be replaced with a * efficient population count instruction or similar. */ #ifdef CONFIG_DCACHE_WORD_ACCESS #include <asm/word-at-a-time.h> #ifdef HASH_MIX /* Architecture provides HASH_MIX and fold_hash() in <asm/hash.h> */ #elif defined(CONFIG_64BIT) /* * Register pressure in the mixing function is an issue, particularly * on 32-bit x86, but almost any function requires one state value and * one temporary. Instead, use a function designed for two state values * and no temporaries. * * This function cannot create a collision in only two iterations, so * we have two iterations to achieve avalanche. In those two iterations, * we have six layers of mixing, which is enough to spread one bit's * influence out to 2^6 = 64 state bits. * * Rotate constants are scored by considering either 64 one-bit input * deltas or 64*63/2 = 2016 two-bit input deltas, and finding the * probability of that delta causing a change to each of the 128 output * bits, using a sample of random initial states. * * The Shannon entropy of the computed probabilities is then summed * to produce a score. Ideally, any input change has a 50% chance of * toggling any given output bit. * * Mixing scores (in bits) for (12,45): * Input delta: 1-bit 2-bit * 1 round: 713.3 42542.6 * 2 rounds: 2753.7 140389.8 * 3 rounds: 5954.1 233458.2 * 4 rounds: 7862.6 256672.2 * Perfect: 8192 258048 * (64*128) (64*63/2 * 128) */ #define HASH_MIX(x, y, a) \ ( x ^= (a), \ y ^= x, x = rol64(x,12),\ x += y, y = rol64(y,45),\ y *= 9 ) /* * Fold two longs into one 32-bit hash value. This must be fast, but * latency isn't quite as critical, as there is a fair bit of additional * work done before the hash value is used. */ static inline unsigned int fold_hash(unsigned long x, unsigned long y) { y ^= x * GOLDEN_RATIO_64; y *= GOLDEN_RATIO_64; return y >> 32; } #else /* 32-bit case */ /* * Mixing scores (in bits) for (7,20): * Input delta: 1-bit 2-bit * 1 round: 330.3 9201.6 * 2 rounds: 1246.4 25475.4 * 3 rounds: 1907.1 31295.1 * 4 rounds: 2042.3 31718.6 * Perfect: 2048 31744 * (32*64) (32*31/2 * 64) */ #define HASH_MIX(x, y, a) \ ( x ^= (a), \ y ^= x, x = rol32(x, 7),\ x += y, y = rol32(y,20),\ y *= 9 ) static inline unsigned int fold_hash(unsigned long x, unsigned long y) { /* Use arch-optimized multiply if one exists */ return __hash_32(y ^ __hash_32(x)); } #endif /* * Return the hash of a string of known length. This is carfully * designed to match hash_name(), which is the more critical function. * In particular, we must end by hashing a final word containing 0..7 * payload bytes, to match the way that hash_name() iterates until it * finds the delimiter after the name. */ unsigned int full_name_hash(const void *salt, const char *name, unsigned int len) { unsigned long a, x = 0, y = (unsigned long)salt; for (;;) { if (!len) goto done; a = load_unaligned_zeropad(name); if (len < sizeof(unsigned long)) break; HASH_MIX(x, y, a); name += sizeof(unsigned long); len -= sizeof(unsigned long); } x ^= a & bytemask_from_count(len); done: return fold_hash(x, y); } EXPORT_SYMBOL(full_name_hash); /* Return the "hash_len" (hash and length) of a null-terminated string */ u64 hashlen_string(const void *salt, const char *name) { unsigned long a = 0, x = 0, y = (unsigned long)salt; unsigned long adata, mask, len; const struct word_at_a_time constants = WORD_AT_A_TIME_CONSTANTS; len = 0; goto inside; do { HASH_MIX(x, y, a); len += sizeof(unsigned long); inside: a = load_unaligned_zeropad(name+len); } while (!has_zero(a, &adata, &constants)); adata = prep_zero_mask(a, adata, &constants); mask = create_zero_mask(adata); x ^= a & zero_bytemask(mask); return hashlen_create(fold_hash(x, y), len + find_zero(mask)); } EXPORT_SYMBOL(hashlen_string); /* * Calculate the length and hash of the path component, and * return the "hash_len" as the result. */ static inline u64 hash_name(const void *salt, const char *name) { unsigned long a = 0, b, x = 0, y = (unsigned long)salt; unsigned long adata, bdata, mask, len; const struct word_at_a_time constants = WORD_AT_A_TIME_CONSTANTS; len = 0; goto inside; do { HASH_MIX(x, y, a); len += sizeof(unsigned long); inside: a = load_unaligned_zeropad(name+len); b = a ^ REPEAT_BYTE('/'); } while (!(has_zero(a, &adata, &constants) | has_zero(b, &bdata, &constants))); adata = prep_zero_mask(a, adata, &constants); bdata = prep_zero_mask(b, bdata, &constants); mask = create_zero_mask(adata | bdata); x ^= a & zero_bytemask(mask); return hashlen_create(fold_hash(x, y), len + find_zero(mask)); } #else /* !CONFIG_DCACHE_WORD_ACCESS: Slow, byte-at-a-time version */ /* Return the hash of a string of known length */ unsigned int full_name_hash(const void *salt, const char *name, unsigned int len) { unsigned long hash = init_name_hash(salt); while (len--) hash = partial_name_hash((unsigned char)*name++, hash); return end_name_hash(hash); } EXPORT_SYMBOL(full_name_hash); /* Return the "hash_len" (hash and length) of a null-terminated string */ u64 hashlen_string(const void *salt, const char *name) { unsigned long hash = init_name_hash(salt); unsigned long len = 0, c; c = (unsigned char)*name; while (c) { len++; hash = partial_name_hash(c, hash); c = (unsigned char)name[len]; } return hashlen_create(end_name_hash(hash), len); } EXPORT_SYMBOL(hashlen_string); /* * We know there's a real path component here of at least * one character. */ static inline u64 hash_name(const void *salt, const char *name) { unsigned long hash = init_name_hash(salt); unsigned long len = 0, c; c = (unsigned char)*name; do { len++; hash = partial_name_hash(c, hash); c = (unsigned char)name[len]; } while (c && c != '/'); return hashlen_create(end_name_hash(hash), len); } #endif /* * Name resolution. * This is the basic name resolution function, turning a pathname into * the final dentry. We expect 'base' to be positive and a directory. * * Returns 0 and nd will have valid dentry and mnt on success. * Returns error and drops reference to input namei data on failure. */ static int link_path_walk(const char *name, struct nameidata *nd) { int depth = 0; // depth <= nd->depth int err; nd->last_type = LAST_ROOT; nd->flags |= LOOKUP_PARENT; if (IS_ERR(name)) return PTR_ERR(name); while (*name=='/') name++; if (!*name) return 0; /* At this point we know we have a real path component. */ for(;;) { const char *link; u64 hash_len; int type; err = may_lookup(nd); if (err) return err; hash_len = hash_name(nd->path.dentry, name); type = LAST_NORM; if (name[0] == '.') switch (hashlen_len(hash_len)) { case 2: if (name[1] == '.') { type = LAST_DOTDOT; nd->flags |= LOOKUP_JUMPED; } break; case 1: type = LAST_DOT; } if (likely(type == LAST_NORM)) { struct dentry *parent = nd->path.dentry; nd->flags &= ~LOOKUP_JUMPED; if (unlikely(parent->d_flags & DCACHE_OP_HASH)) { struct qstr this = { { .hash_len = hash_len }, .name = name }; err = parent->d_op->d_hash(parent, &this); if (err < 0) return err; hash_len = this.hash_len; name = this.name; } } nd->last.hash_len = hash_len; nd->last.name = name; nd->last_type = type; name += hashlen_len(hash_len); if (!*name) goto OK; /* * If it wasn't NUL, we know it was '/'. Skip that * slash, and continue until no more slashes. */ do { name++; } while (unlikely(*name == '/')); if (unlikely(!*name)) { OK: /* pathname or trailing symlink, done */ if (!depth) { nd->dir_uid = nd->inode->i_uid; nd->dir_mode = nd->inode->i_mode; nd->flags &= ~LOOKUP_PARENT; return 0; } /* last component of nested symlink */ name = nd->stack[--depth].name; link = walk_component(nd, 0); } else { /* not the last component */ link = walk_component(nd, WALK_MORE); } if (unlikely(link)) { if (IS_ERR(link)) return PTR_ERR(link); /* a symlink to follow */ nd->stack[depth++].name = name; name = link; continue; } if (unlikely(!d_can_lookup(nd->path.dentry))) { if (nd->flags & LOOKUP_RCU) { if (!try_to_unlazy(nd)) return -ECHILD; } return -ENOTDIR; } } } /* must be paired with terminate_walk() */ static const char *path_init(struct nameidata *nd, unsigned flags) { int error; const char *s = nd->name->name; if (!*s) flags &= ~LOOKUP_RCU; if (flags & LOOKUP_RCU) rcu_read_lock(); nd->flags = flags | LOOKUP_JUMPED; nd->depth = 0; nd->m_seq = __read_seqcount_begin(&mount_lock.seqcount); nd->r_seq = __read_seqcount_begin(&rename_lock.seqcount); smp_rmb(); if (flags & LOOKUP_ROOT) { struct dentry *root = nd->root.dentry; struct inode *inode = root->d_inode; if (*s && unlikely(!d_can_lookup(root))) return ERR_PTR(-ENOTDIR); nd->path = nd->root; nd->inode = inode; if (flags & LOOKUP_RCU) { nd->seq = read_seqcount_begin(&nd->path.dentry->d_seq); nd->root_seq = nd->seq; } else { path_get(&nd->path); } return s; } nd->root.mnt = NULL; nd->path.mnt = NULL; nd->path.dentry = NULL; /* Absolute pathname -- fetch the root (LOOKUP_IN_ROOT uses nd->dfd). */ if (*s == '/' && !(flags & LOOKUP_IN_ROOT)) { error = nd_jump_root(nd); if (unlikely(error)) return ERR_PTR(error); return s; } /* Relative pathname -- get the starting-point it is relative to. */ if (nd->dfd == AT_FDCWD) { if (flags & LOOKUP_RCU) { struct fs_struct *fs = current->fs; unsigned seq; do { seq = read_seqcount_begin(&fs->seq); nd->path = fs->pwd; nd->inode = nd->path.dentry->d_inode; nd->seq = __read_seqcount_begin(&nd->path.dentry->d_seq); } while (read_seqcount_retry(&fs->seq, seq)); } else { get_fs_pwd(current->fs, &nd->path); nd->inode = nd->path.dentry->d_inode; } } else { /* Caller must check execute permissions on the starting path component */ struct fd f = fdget_raw(nd->dfd); struct dentry *dentry; if (!f.file) return ERR_PTR(-EBADF); dentry = f.file->f_path.dentry; if (*s && unlikely(!d_can_lookup(dentry))) { fdput(f); return ERR_PTR(-ENOTDIR); } nd->path = f.file->f_path; if (flags & LOOKUP_RCU) { nd->inode = nd->path.dentry->d_inode; nd->seq = read_seqcount_begin(&nd->path.dentry->d_seq); } else { path_get(&nd->path); nd->inode = nd->path.dentry->d_inode; } fdput(f); } /* For scoped-lookups we need to set the root to the dirfd as well. */ if (flags & LOOKUP_IS_SCOPED) { nd->root = nd->path; if (flags & LOOKUP_RCU) { nd->root_seq = nd->seq; } else { path_get(&nd->root); nd->flags |= LOOKUP_ROOT_GRABBED; } } return s; } static inline const char *lookup_last(struct nameidata *nd) { if (nd->last_type == LAST_NORM && nd->last.name[nd->last.len]) nd->flags |= LOOKUP_FOLLOW | LOOKUP_DIRECTORY; return walk_component(nd, WALK_TRAILING); } static int handle_lookup_down(struct nameidata *nd) { if (!(nd->flags & LOOKUP_RCU)) dget(nd->path.dentry); return PTR_ERR(step_into(nd, WALK_NOFOLLOW, nd->path.dentry, nd->inode, nd->seq)); } /* Returns 0 and nd will be valid on success; Retuns error, otherwise. */ static int path_lookupat(struct nameidata *nd, unsigned flags, struct path *path) { const char *s = path_init(nd, flags); int err; if (unlikely(flags & LOOKUP_DOWN) && !IS_ERR(s)) { err = handle_lookup_down(nd); if (unlikely(err < 0)) s = ERR_PTR(err); } while (!(err = link_path_walk(s, nd)) && (s = lookup_last(nd)) != NULL) ; if (!err && unlikely(nd->flags & LOOKUP_MOUNTPOINT)) { err = handle_lookup_down(nd); nd->flags &= ~LOOKUP_JUMPED; // no d_weak_revalidate(), please... } if (!err) err = complete_walk(nd); if (!err && nd->flags & LOOKUP_DIRECTORY) if (!d_can_lookup(nd->path.dentry)) err = -ENOTDIR; if (!err) { *path = nd->path; nd->path.mnt = NULL; nd->path.dentry = NULL; } terminate_walk(nd); return err; } int filename_lookup(int dfd, struct filename *name, unsigned flags, struct path *path, struct path *root) { int retval; struct nameidata nd; if (IS_ERR(name)) return PTR_ERR(name); if (unlikely(root)) { nd.root = *root; flags |= LOOKUP_ROOT; } set_nameidata(&nd, dfd, name); retval = path_lookupat(&nd, flags | LOOKUP_RCU, path); if (unlikely(retval == -ECHILD)) retval = path_lookupat(&nd, flags, path); if (unlikely(retval == -ESTALE)) retval = path_lookupat(&nd, flags | LOOKUP_REVAL, path); if (likely(!retval)) audit_inode(name, path->dentry, flags & LOOKUP_MOUNTPOINT ? AUDIT_INODE_NOEVAL : 0); restore_nameidata(); putname(name); return retval; } /* Returns 0 and nd will be valid on success; Retuns error, otherwise. */ static int path_parentat(struct nameidata *nd, unsigned flags, struct path *parent) { const char *s = path_init(nd, flags); int err = link_path_walk(s, nd); if (!err) err = complete_walk(nd); if (!err) { *parent = nd->path; nd->path.mnt = NULL; nd->path.dentry = NULL; } terminate_walk(nd); return err; } static struct filename *filename_parentat(int dfd, struct filename *name, unsigned int flags, struct path *parent, struct qstr *last, int *type) { int retval; struct nameidata nd; if (IS_ERR(name)) return name; set_nameidata(&nd, dfd, name); retval = path_parentat(&nd, flags | LOOKUP_RCU, parent); if (unlikely(retval == -ECHILD)) retval = path_parentat(&nd, flags, parent); if (unlikely(retval == -ESTALE)) retval = path_parentat(&nd, flags | LOOKUP_REVAL, parent); if (likely(!retval)) { *last = nd.last; *type = nd.last_type; audit_inode(name, parent->dentry, AUDIT_INODE_PARENT); } else { putname(name); name = ERR_PTR(retval); } restore_nameidata(); return name; } /* does lookup, returns the object with parent locked */ struct dentry *kern_path_locked(const char *name, struct path *path) { struct filename *filename; struct dentry *d; struct qstr last; int type; filename = filename_parentat(AT_FDCWD, getname_kernel(name), 0, path, &last, &type); if (IS_ERR(filename)) return ERR_CAST(filename); if (unlikely(type != LAST_NORM)) { path_put(path); putname(filename); return ERR_PTR(-EINVAL); } inode_lock_nested(path->dentry->d_inode, I_MUTEX_PARENT); d = __lookup_hash(&last, path->dentry, 0); if (IS_ERR(d)) { inode_unlock(path->dentry->d_inode); path_put(path); } putname(filename); return d; } int kern_path(const char *name, unsigned int flags, struct path *path) { return filename_lookup(AT_FDCWD, getname_kernel(name), flags, path, NULL); } EXPORT_SYMBOL(kern_path); /** * vfs_path_lookup - lookup a file path relative to a dentry-vfsmount pair * @dentry: pointer to dentry of the base directory * @mnt: pointer to vfs mount of the base directory * @name: pointer to file name * @flags: lookup flags * @path: pointer to struct path to fill */ int vfs_path_lookup(struct dentry *dentry, struct vfsmount *mnt, const char *name, unsigned int flags, struct path *path) { struct path root = {.mnt = mnt, .dentry = dentry}; /* the first argument of filename_lookup() is ignored with root */ return filename_lookup(AT_FDCWD, getname_kernel(name), flags , path, &root); } EXPORT_SYMBOL(vfs_path_lookup); static int lookup_one_len_common(const char *name, struct dentry *base, int len, struct qstr *this) { this->name = name; this->len = len; this->hash = full_name_hash(base, name, len); if (!len) return -EACCES; if (unlikely(name[0] == '.')) { if (len < 2 || (len == 2 && name[1] == '.')) return -EACCES; } while (len--) { unsigned int c = *(const unsigned char *)name++; if (c == '/' || c == '\0') return -EACCES; } /* * See if the low-level filesystem might want * to use its own hash.. */ if (base->d_flags & DCACHE_OP_HASH) { int err = base->d_op->d_hash(base, this); if (err < 0) return err; } return inode_permission(base->d_inode, MAY_EXEC); } /** * try_lookup_one_len - filesystem helper to lookup single pathname component * @name: pathname component to lookup * @base: base directory to lookup from * @len: maximum length @len should be interpreted to * * Look up a dentry by name in the dcache, returning NULL if it does not * currently exist. The function does not try to create a dentry. * * Note that this routine is purely a helper for filesystem usage and should * not be called by generic code. * * The caller must hold base->i_mutex. */ struct dentry *try_lookup_one_len(const char *name, struct dentry *base, int len) { struct qstr this; int err; WARN_ON_ONCE(!inode_is_locked(base->d_inode)); err = lookup_one_len_common(name, base, len, &this); if (err) return ERR_PTR(err); return lookup_dcache(&this, base, 0); } EXPORT_SYMBOL(try_lookup_one_len); /** * lookup_one_len - filesystem helper to lookup single pathname component * @name: pathname component to lookup * @base: base directory to lookup from * @len: maximum length @len should be interpreted to * * Note that this routine is purely a helper for filesystem usage and should * not be called by generic code. * * The caller must hold base->i_mutex. */ struct dentry *lookup_one_len(const char *name, struct dentry *base, int len) { struct dentry *dentry; struct qstr this; int err; WARN_ON_ONCE(!inode_is_locked(base->d_inode)); err = lookup_one_len_common(name, base, len, &this); if (err) return ERR_PTR(err); dentry = lookup_dcache(&this, base, 0); return dentry ? dentry : __lookup_slow(&this, base, 0); } EXPORT_SYMBOL(lookup_one_len); /** * lookup_one_len_unlocked - filesystem helper to lookup single pathname component * @name: pathname component to lookup * @base: base directory to lookup from * @len: maximum length @len should be interpreted to * * Note that this routine is purely a helper for filesystem usage and should * not be called by generic code. * * Unlike lookup_one_len, it should be called without the parent * i_mutex held, and will take the i_mutex itself if necessary. */ struct dentry *lookup_one_len_unlocked(const char *name, struct dentry *base, int len) { struct qstr this; int err; struct dentry *ret; err = lookup_one_len_common(name, base, len, &this); if (err) return ERR_PTR(err); ret = lookup_dcache(&this, base, 0); if (!ret) ret = lookup_slow(&this, base, 0); return ret; } EXPORT_SYMBOL(lookup_one_len_unlocked); /* * Like lookup_one_len_unlocked(), except that it yields ERR_PTR(-ENOENT) * on negatives. Returns known positive or ERR_PTR(); that's what * most of the users want. Note that pinned negative with unlocked parent * _can_ become positive at any time, so callers of lookup_one_len_unlocked() * need to be very careful; pinned positives have ->d_inode stable, so * this one avoids such problems. */ struct dentry *lookup_positive_unlocked(const char *name, struct dentry *base, int len) { struct dentry *ret = lookup_one_len_unlocked(name, base, len); if (!IS_ERR(ret) && d_flags_negative(smp_load_acquire(&ret->d_flags))) { dput(ret); ret = ERR_PTR(-ENOENT); } return ret; } EXPORT_SYMBOL(lookup_positive_unlocked); #ifdef CONFIG_UNIX98_PTYS int path_pts(struct path *path) { /* Find something mounted on "pts" in the same directory as * the input path. */ struct dentry *parent = dget_parent(path->dentry); struct dentry *child; struct qstr this = QSTR_INIT("pts", 3); if (unlikely(!path_connected(path->mnt, parent))) { dput(parent); return -ENOENT; } dput(path->dentry); path->dentry = parent; child = d_hash_and_lookup(parent, &this); if (!child) return -ENOENT; path->dentry = child; dput(parent); follow_down(path); return 0; } #endif int user_path_at_empty(int dfd, const char __user *name, unsigned flags, struct path *path, int *empty) { return filename_lookup(dfd, getname_flags(name, flags, empty), flags, path, NULL); } EXPORT_SYMBOL(user_path_at_empty); int __check_sticky(struct inode *dir, struct inode *inode) { kuid_t fsuid = current_fsuid(); if (uid_eq(inode->i_uid, fsuid)) return 0; if (uid_eq(dir->i_uid, fsuid)) return 0; return !capable_wrt_inode_uidgid(inode, CAP_FOWNER); } EXPORT_SYMBOL(__check_sticky); /* * Check whether we can remove a link victim from directory dir, check * whether the type of victim is right. * 1. We can't do it if dir is read-only (done in permission()) * 2. We should have write and exec permissions on dir * 3. We can't remove anything from append-only dir * 4. We can't do anything with immutable dir (done in permission()) * 5. If the sticky bit on dir is set we should either * a. be owner of dir, or * b. be owner of victim, or * c. have CAP_FOWNER capability * 6. If the victim is append-only or immutable we can't do antyhing with * links pointing to it. * 7. If the victim has an unknown uid or gid we can't change the inode. * 8. If we were asked to remove a directory and victim isn't one - ENOTDIR. * 9. If we were asked to remove a non-directory and victim isn't one - EISDIR. * 10. We can't remove a root or mountpoint. * 11. We don't allow removal of NFS sillyrenamed files; it's handled by * nfs_async_unlink(). */ static int may_delete(struct inode *dir, struct dentry *victim, bool isdir) { struct inode *inode = d_backing_inode(victim); int error; if (d_is_negative(victim)) return -ENOENT; BUG_ON(!inode); BUG_ON(victim->d_parent->d_inode != dir); /* Inode writeback is not safe when the uid or gid are invalid. */ if (!uid_valid(inode->i_uid) || !gid_valid(inode->i_gid)) return -EOVERFLOW; audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE); error = inode_permission(dir, MAY_WRITE | MAY_EXEC); if (error) return error; if (IS_APPEND(dir)) return -EPERM; if (check_sticky(dir, inode) || IS_APPEND(inode) || IS_IMMUTABLE(inode) || IS_SWAPFILE(inode) || HAS_UNMAPPED_ID(inode)) return -EPERM; if (isdir) { if (!d_is_dir(victim)) return -ENOTDIR; if (IS_ROOT(victim)) return -EBUSY; } else if (d_is_dir(victim)) return -EISDIR; if (IS_DEADDIR(dir)) return -ENOENT; if (victim->d_flags & DCACHE_NFSFS_RENAMED) return -EBUSY; return 0; } /* Check whether we can create an object with dentry child in directory * dir. * 1. We can't do it if child already exists (open has special treatment for * this case, but since we are inlined it's OK) * 2. We can't do it if dir is read-only (done in permission()) * 3. We can't do it if the fs can't represent the fsuid or fsgid. * 4. We should have write and exec permissions on dir * 5. We can't do it if dir is immutable (done in permission()) */ static inline int may_create(struct inode *dir, struct dentry *child) { struct user_namespace *s_user_ns; audit_inode_child(dir, child, AUDIT_TYPE_CHILD_CREATE); if (child->d_inode) return -EEXIST; if (IS_DEADDIR(dir)) return -ENOENT; s_user_ns = dir->i_sb->s_user_ns; if (!kuid_has_mapping(s_user_ns, current_fsuid()) || !kgid_has_mapping(s_user_ns, current_fsgid())) return -EOVERFLOW; return inode_permission(dir, MAY_WRITE | MAY_EXEC); } /* * p1 and p2 should be directories on the same fs. */ struct dentry *lock_rename(struct dentry *p1, struct dentry *p2) { struct dentry *p; if (p1 == p2) { inode_lock_nested(p1->d_inode, I_MUTEX_PARENT); return NULL; } mutex_lock(&p1->d_sb->s_vfs_rename_mutex); p = d_ancestor(p2, p1); if (p) { inode_lock_nested(p2->d_inode, I_MUTEX_PARENT); inode_lock_nested(p1->d_inode, I_MUTEX_CHILD); return p; } p = d_ancestor(p1, p2); if (p) { inode_lock_nested(p1->d_inode, I_MUTEX_PARENT); inode_lock_nested(p2->d_inode, I_MUTEX_CHILD); return p; } inode_lock_nested(p1->d_inode, I_MUTEX_PARENT); inode_lock_nested(p2->d_inode, I_MUTEX_PARENT2); return NULL; } EXPORT_SYMBOL(lock_rename); void unlock_rename(struct dentry *p1, struct dentry *p2) { inode_unlock(p1->d_inode); if (p1 != p2) { inode_unlock(p2->d_inode); mutex_unlock(&p1->d_sb->s_vfs_rename_mutex); } } EXPORT_SYMBOL(unlock_rename); int vfs_create(struct inode *dir, struct dentry *dentry, umode_t mode, bool want_excl) { int error = may_create(dir, dentry); if (error) return error; if (!dir->i_op->create) return -EACCES; /* shouldn't it be ENOSYS? */ mode &= S_IALLUGO; mode |= S_IFREG; error = security_inode_create(dir, dentry, mode); if (error) return error; error = dir->i_op->create(dir, dentry, mode, want_excl); if (!error) fsnotify_create(dir, dentry); return error; } EXPORT_SYMBOL(vfs_create); int vfs_mkobj(struct dentry *dentry, umode_t mode, int (*f)(struct dentry *, umode_t, void *), void *arg) { struct inode *dir = dentry->d_parent->d_inode; int error = may_create(dir, dentry); if (error) return error; mode &= S_IALLUGO; mode |= S_IFREG; error = security_inode_create(dir, dentry, mode); if (error) return error; error = f(dentry, mode, arg); if (!error) fsnotify_create(dir, dentry); return error; } EXPORT_SYMBOL(vfs_mkobj); bool may_open_dev(const struct path *path) { return !(path->mnt->mnt_flags & MNT_NODEV) && !(path->mnt->mnt_sb->s_iflags & SB_I_NODEV); } static int may_open(const struct path *path, int acc_mode, int flag) { struct dentry *dentry = path->dentry; struct inode *inode = dentry->d_inode; int error; if (!inode) return -ENOENT; switch (inode->i_mode & S_IFMT) { case S_IFLNK: return -ELOOP; case S_IFDIR: if (acc_mode & MAY_WRITE) return -EISDIR; if (acc_mode & MAY_EXEC) return -EACCES; break; case S_IFBLK: case S_IFCHR: if (!may_open_dev(path)) return -EACCES; fallthrough; case S_IFIFO: case S_IFSOCK: if (acc_mode & MAY_EXEC) return -EACCES; flag &= ~O_TRUNC; break; case S_IFREG: if ((acc_mode & MAY_EXEC) && path_noexec(path)) return -EACCES; break; } error = inode_permission(inode, MAY_OPEN | acc_mode); if (error) return error; /* * An append-only file must be opened in append mode for writing. */ if (IS_APPEND(inode)) { if ((flag & O_ACCMODE) != O_RDONLY && !(flag & O_APPEND)) return -EPERM; if (flag & O_TRUNC) return -EPERM; } /* O_NOATIME can only be set by the owner or superuser */ if (flag & O_NOATIME && !inode_owner_or_capable(inode)) return -EPERM; return 0; } static int handle_truncate(struct file *filp) { const struct path *path = &filp->f_path; struct inode *inode = path->dentry->d_inode; int error = get_write_access(inode); if (error) return error; /* * Refuse to truncate files with mandatory locks held on them. */ error = locks_verify_locked(filp); if (!error) error = security_path_truncate(path); if (!error) { error = do_truncate(path->dentry, 0, ATTR_MTIME|ATTR_CTIME|ATTR_OPEN, filp); } put_write_access(inode); return error; } static inline int open_to_namei_flags(int flag) { if ((flag & O_ACCMODE) == 3) flag--; return flag; } static int may_o_create(const struct path *dir, struct dentry *dentry, umode_t mode) { struct user_namespace *s_user_ns; int error = security_path_mknod(dir, dentry, mode, 0); if (error) return error; s_user_ns = dir->dentry->d_sb->s_user_ns; if (!kuid_has_mapping(s_user_ns, current_fsuid()) || !kgid_has_mapping(s_user_ns, current_fsgid())) return -EOVERFLOW; error = inode_permission(dir->dentry->d_inode, MAY_WRITE | MAY_EXEC); if (error) return error; return security_inode_create(dir->dentry->d_inode, dentry, mode); } /* * Attempt to atomically look up, create and open a file from a negative * dentry. * * Returns 0 if successful. The file will have been created and attached to * @file by the filesystem calling finish_open(). * * If the file was looked up only or didn't need creating, FMODE_OPENED won't * be set. The caller will need to perform the open themselves. @path will * have been updated to point to the new dentry. This may be negative. * * Returns an error code otherwise. */ static struct dentry *atomic_open(struct nameidata *nd, struct dentry *dentry, struct file *file, int open_flag, umode_t mode) { struct dentry *const DENTRY_NOT_SET = (void *) -1UL; struct inode *dir = nd->path.dentry->d_inode; int error; if (nd->flags & LOOKUP_DIRECTORY) open_flag |= O_DIRECTORY; file->f_path.dentry = DENTRY_NOT_SET; file->f_path.mnt = nd->path.mnt; error = dir->i_op->atomic_open(dir, dentry, file, open_to_namei_flags(open_flag), mode); d_lookup_done(dentry); if (!error) { if (file->f_mode & FMODE_OPENED) { if (unlikely(dentry != file->f_path.dentry)) { dput(dentry); dentry = dget(file->f_path.dentry); } } else if (WARN_ON(file->f_path.dentry == DENTRY_NOT_SET)) { error = -EIO; } else { if (file->f_path.dentry) { dput(dentry); dentry = file->f_path.dentry; } if (unlikely(d_is_negative(dentry))) error = -ENOENT; } } if (error) { dput(dentry); dentry = ERR_PTR(error); } return dentry; } /* * Look up and maybe create and open the last component. * * Must be called with parent locked (exclusive in O_CREAT case). * * Returns 0 on success, that is, if * the file was successfully atomically created (if necessary) and opened, or * the file was not completely opened at this time, though lookups and * creations were performed. * These case are distinguished by presence of FMODE_OPENED on file->f_mode. * In the latter case dentry returned in @path might be negative if O_CREAT * hadn't been specified. * * An error code is returned on failure. */ static struct dentry *lookup_open(struct nameidata *nd, struct file *file, const struct open_flags *op, bool got_write) { struct dentry *dir = nd->path.dentry; struct inode *dir_inode = dir->d_inode; int open_flag = op->open_flag; struct dentry *dentry; int error, create_error = 0; umode_t mode = op->mode; DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq); if (unlikely(IS_DEADDIR(dir_inode))) return ERR_PTR(-ENOENT); file->f_mode &= ~FMODE_CREATED; dentry = d_lookup(dir, &nd->last); for (;;) { if (!dentry) { dentry = d_alloc_parallel(dir, &nd->last, &wq); if (IS_ERR(dentry)) return dentry; } if (d_in_lookup(dentry)) break; error = d_revalidate(dentry, nd->flags); if (likely(error > 0)) break; if (error) goto out_dput; d_invalidate(dentry); dput(dentry); dentry = NULL; } if (dentry->d_inode) { /* Cached positive dentry: will open in f_op->open */ return dentry; } /* * Checking write permission is tricky, bacuse we don't know if we are * going to actually need it: O_CREAT opens should work as long as the * file exists. But checking existence breaks atomicity. The trick is * to check access and if not granted clear O_CREAT from the flags. * * Another problem is returing the "right" error value (e.g. for an * O_EXCL open we want to return EEXIST not EROFS). */ if (unlikely(!got_write)) open_flag &= ~O_TRUNC; if (open_flag & O_CREAT) { if (open_flag & O_EXCL) open_flag &= ~O_TRUNC; if (!IS_POSIXACL(dir->d_inode)) mode &= ~current_umask(); if (likely(got_write)) create_error = may_o_create(&nd->path, dentry, mode); else create_error = -EROFS; } if (create_error) open_flag &= ~O_CREAT; if (dir_inode->i_op->atomic_open) { dentry = atomic_open(nd, dentry, file, open_flag, mode); if (unlikely(create_error) && dentry == ERR_PTR(-ENOENT)) dentry = ERR_PTR(create_error); return dentry; } if (d_in_lookup(dentry)) { struct dentry *res = dir_inode->i_op->lookup(dir_inode, dentry, nd->flags); d_lookup_done(dentry); if (unlikely(res)) { if (IS_ERR(res)) { error = PTR_ERR(res); goto out_dput; } dput(dentry); dentry = res; } } /* Negative dentry, just create the file */ if (!dentry->d_inode && (open_flag & O_CREAT)) { file->f_mode |= FMODE_CREATED; audit_inode_child(dir_inode, dentry, AUDIT_TYPE_CHILD_CREATE); if (!dir_inode->i_op->create) { error = -EACCES; goto out_dput; } error = dir_inode->i_op->create(dir_inode, dentry, mode, open_flag & O_EXCL); if (error) goto out_dput; } if (unlikely(create_error) && !dentry->d_inode) { error = create_error; goto out_dput; } return dentry; out_dput: dput(dentry); return ERR_PTR(error); } static const char *open_last_lookups(struct nameidata *nd, struct file *file, const struct open_flags *op) { struct dentry *dir = nd->path.dentry; int open_flag = op->open_flag; bool got_write = false; unsigned seq; struct inode *inode; struct dentry *dentry; const char *res; nd->flags |= op->intent; if (nd->last_type != LAST_NORM) { if (nd->depth) put_link(nd); return handle_dots(nd, nd->last_type); } if (!(open_flag & O_CREAT)) { if (nd->last.name[nd->last.len]) nd->flags |= LOOKUP_FOLLOW | LOOKUP_DIRECTORY; /* we _can_ be in RCU mode here */ dentry = lookup_fast(nd, &inode, &seq); if (IS_ERR(dentry)) return ERR_CAST(dentry); if (likely(dentry)) goto finish_lookup; BUG_ON(nd->flags & LOOKUP_RCU); } else { /* create side of things */ if (nd->flags & LOOKUP_RCU) { if (!try_to_unlazy(nd)) return ERR_PTR(-ECHILD); } audit_inode(nd->name, dir, AUDIT_INODE_PARENT); /* trailing slashes? */ if (unlikely(nd->last.name[nd->last.len])) return ERR_PTR(-EISDIR); } if (open_flag & (O_CREAT | O_TRUNC | O_WRONLY | O_RDWR)) { got_write = !mnt_want_write(nd->path.mnt); /* * do _not_ fail yet - we might not need that or fail with * a different error; let lookup_open() decide; we'll be * dropping this one anyway. */ } if (open_flag & O_CREAT) inode_lock(dir->d_inode); else inode_lock_shared(dir->d_inode); dentry = lookup_open(nd, file, op, got_write); if (!IS_ERR(dentry) && (file->f_mode & FMODE_CREATED)) fsnotify_create(dir->d_inode, dentry); if (open_flag & O_CREAT) inode_unlock(dir->d_inode); else inode_unlock_shared(dir->d_inode); if (got_write) mnt_drop_write(nd->path.mnt); if (IS_ERR(dentry)) return ERR_CAST(dentry); if (file->f_mode & (FMODE_OPENED | FMODE_CREATED)) { dput(nd->path.dentry); nd->path.dentry = dentry; return NULL; } finish_lookup: if (nd->depth) put_link(nd); res = step_into(nd, WALK_TRAILING, dentry, inode, seq); if (unlikely(res)) nd->flags &= ~(LOOKUP_OPEN|LOOKUP_CREATE|LOOKUP_EXCL); return res; } /* * Handle the last step of open() */ static int do_open(struct nameidata *nd, struct file *file, const struct open_flags *op) { int open_flag = op->open_flag; bool do_truncate; int acc_mode; int error; if (!(file->f_mode & (FMODE_OPENED | FMODE_CREATED))) { error = complete_walk(nd); if (error) return error; } if (!(file->f_mode & FMODE_CREATED)) audit_inode(nd->name, nd->path.dentry, 0); if (open_flag & O_CREAT) { if ((open_flag & O_EXCL) && !(file->f_mode & FMODE_CREATED)) return -EEXIST; if (d_is_dir(nd->path.dentry)) return -EISDIR; error = may_create_in_sticky(nd->dir_mode, nd->dir_uid, d_backing_inode(nd->path.dentry)); if (unlikely(error)) return error; } if ((nd->flags & LOOKUP_DIRECTORY) && !d_can_lookup(nd->path.dentry)) return -ENOTDIR; do_truncate = false; acc_mode = op->acc_mode; if (file->f_mode & FMODE_CREATED) { /* Don't check for write permission, don't truncate */ open_flag &= ~O_TRUNC; acc_mode = 0; } else if (d_is_reg(nd->path.dentry) && open_flag & O_TRUNC) { error = mnt_want_write(nd->path.mnt); if (error) return error; do_truncate = true; } error = may_open(&nd->path, acc_mode, open_flag); if (!error && !(file->f_mode & FMODE_OPENED)) error = vfs_open(&nd->path, file); if (!error) error = ima_file_check(file, op->acc_mode); if (!error && do_truncate) error = handle_truncate(file); if (unlikely(error > 0)) { WARN_ON(1); error = -EINVAL; } if (do_truncate) mnt_drop_write(nd->path.mnt); return error; } struct dentry *vfs_tmpfile(struct dentry *dentry, umode_t mode, int open_flag) { struct dentry *child = NULL; struct inode *dir = dentry->d_inode; struct inode *inode; int error; /* we want directory to be writable */ error = inode_permission(dir, MAY_WRITE | MAY_EXEC); if (error) goto out_err; error = -EOPNOTSUPP; if (!dir->i_op->tmpfile) goto out_err; error = -ENOMEM; child = d_alloc(dentry, &slash_name); if (unlikely(!child)) goto out_err; error = dir->i_op->tmpfile(dir, child, mode); if (error) goto out_err; error = -ENOENT; inode = child->d_inode; if (unlikely(!inode)) goto out_err; if (!(open_flag & O_EXCL)) { spin_lock(&inode->i_lock); inode->i_state |= I_LINKABLE; spin_unlock(&inode->i_lock); } ima_post_create_tmpfile(inode); return child; out_err: dput(child); return ERR_PTR(error); } EXPORT_SYMBOL(vfs_tmpfile); static int do_tmpfile(struct nameidata *nd, unsigned flags, const struct open_flags *op, struct file *file) { struct dentry *child; struct path path; int error = path_lookupat(nd, flags | LOOKUP_DIRECTORY, &path); if (unlikely(error)) return error; error = mnt_want_write(path.mnt); if (unlikely(error)) goto out; child = vfs_tmpfile(path.dentry, op->mode, op->open_flag); error = PTR_ERR(child); if (IS_ERR(child)) goto out2; dput(path.dentry); path.dentry = child; audit_inode(nd->name, child, 0); /* Don't check for other permissions, the inode was just created */ error = may_open(&path, 0, op->open_flag); if (error) goto out2; file->f_path.mnt = path.mnt; error = finish_open(file, child, NULL); out2: mnt_drop_write(path.mnt); out: path_put(&path); return error; } static int do_o_path(struct nameidata *nd, unsigned flags, struct file *file) { struct path path; int error = path_lookupat(nd, flags, &path); if (!error) { audit_inode(nd->name, path.dentry, 0); error = vfs_open(&path, file); path_put(&path); } return error; } static struct file *path_openat(struct nameidata *nd, const struct open_flags *op, unsigned flags) { struct file *file; int error; file = alloc_empty_file(op->open_flag, current_cred()); if (IS_ERR(file)) return file; if (unlikely(file->f_flags & __O_TMPFILE)) { error = do_tmpfile(nd, flags, op, file); } else if (unlikely(file->f_flags & O_PATH)) { error = do_o_path(nd, flags, file); } else { const char *s = path_init(nd, flags); while (!(error = link_path_walk(s, nd)) && (s = open_last_lookups(nd, file, op)) != NULL) ; if (!error) error = do_open(nd, file, op); terminate_walk(nd); } if (likely(!error)) { if (likely(file->f_mode & FMODE_OPENED)) return file; WARN_ON(1); error = -EINVAL; } fput(file); if (error == -EOPENSTALE) { if (flags & LOOKUP_RCU) error = -ECHILD; else error = -ESTALE; } return ERR_PTR(error); } struct file *do_filp_open(int dfd, struct filename *pathname, const struct open_flags *op) { struct nameidata nd; int flags = op->lookup_flags; struct file *filp; set_nameidata(&nd, dfd, pathname); filp = path_openat(&nd, op, flags | LOOKUP_RCU); if (unlikely(filp == ERR_PTR(-ECHILD))) filp = path_openat(&nd, op, flags); if (unlikely(filp == ERR_PTR(-ESTALE))) filp = path_openat(&nd, op, flags | LOOKUP_REVAL); restore_nameidata(); return filp; } struct file *do_file_open_root(struct dentry *dentry, struct vfsmount *mnt, const char *name, const struct open_flags *op) { struct nameidata nd; struct file *file; struct filename *filename; int flags = op->lookup_flags | LOOKUP_ROOT; nd.root.mnt = mnt; nd.root.dentry = dentry; if (d_is_symlink(dentry) && op->intent & LOOKUP_OPEN) return ERR_PTR(-ELOOP); filename = getname_kernel(name); if (IS_ERR(filename)) return ERR_CAST(filename); set_nameidata(&nd, -1, filename); file = path_openat(&nd, op, flags | LOOKUP_RCU); if (unlikely(file == ERR_PTR(-ECHILD))) file = path_openat(&nd, op, flags); if (unlikely(file == ERR_PTR(-ESTALE))) file = path_openat(&nd, op, flags | LOOKUP_REVAL); restore_nameidata(); putname(filename); return file; } static struct dentry *filename_create(int dfd, struct filename *name, struct path *path, unsigned int lookup_flags) { struct dentry *dentry = ERR_PTR(-EEXIST); struct qstr last; int type; int err2; int error; bool is_dir = (lookup_flags & LOOKUP_DIRECTORY); /* * Note that only LOOKUP_REVAL and LOOKUP_DIRECTORY matter here. Any * other flags passed in are ignored! */ lookup_flags &= LOOKUP_REVAL; name = filename_parentat(dfd, name, lookup_flags, path, &last, &type); if (IS_ERR(name)) return ERR_CAST(name); /* * Yucky last component or no last component at all? * (foo/., foo/.., /////) */ if (unlikely(type != LAST_NORM)) goto out; /* don't fail immediately if it's r/o, at least try to report other errors */ err2 = mnt_want_write(path->mnt); /* * Do the final lookup. */ lookup_flags |= LOOKUP_CREATE | LOOKUP_EXCL; inode_lock_nested(path->dentry->d_inode, I_MUTEX_PARENT); dentry = __lookup_hash(&last, path->dentry, lookup_flags); if (IS_ERR(dentry)) goto unlock; error = -EEXIST; if (d_is_positive(dentry)) goto fail; /* * Special case - lookup gave negative, but... we had foo/bar/ * From the vfs_mknod() POV we just have a negative dentry - * all is fine. Let's be bastards - you had / on the end, you've * been asking for (non-existent) directory. -ENOENT for you. */ if (unlikely(!is_dir && last.name[last.len])) { error = -ENOENT; goto fail; } if (unlikely(err2)) { error = err2; goto fail; } putname(name); return dentry; fail: dput(dentry); dentry = ERR_PTR(error); unlock: inode_unlock(path->dentry->d_inode); if (!err2) mnt_drop_write(path->mnt); out: path_put(path); putname(name); return dentry; } struct dentry *kern_path_create(int dfd, const char *pathname, struct path *path, unsigned int lookup_flags) { return filename_create(dfd, getname_kernel(pathname), path, lookup_flags); } EXPORT_SYMBOL(kern_path_create); void done_path_create(struct path *path, struct dentry *dentry) { dput(dentry); inode_unlock(path->dentry->d_inode); mnt_drop_write(path->mnt); path_put(path); } EXPORT_SYMBOL(done_path_create); inline struct dentry *user_path_create(int dfd, const char __user *pathname, struct path *path, unsigned int lookup_flags) { return filename_create(dfd, getname(pathname), path, lookup_flags); } EXPORT_SYMBOL(user_path_create); int vfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) { bool is_whiteout = S_ISCHR(mode) && dev == WHITEOUT_DEV; int error = may_create(dir, dentry); if (error) return error; if ((S_ISCHR(mode) || S_ISBLK(mode)) && !is_whiteout && !capable(CAP_MKNOD)) return -EPERM; if (!dir->i_op->mknod) return -EPERM; error = devcgroup_inode_mknod(mode, dev); if (error) return error; error = security_inode_mknod(dir, dentry, mode, dev); if (error) return error; error = dir->i_op->mknod(dir, dentry, mode, dev); if (!error) fsnotify_create(dir, dentry); return error; } EXPORT_SYMBOL(vfs_mknod); static int may_mknod(umode_t mode) { switch (mode & S_IFMT) { case S_IFREG: case S_IFCHR: case S_IFBLK: case S_IFIFO: case S_IFSOCK: case 0: /* zero mode translates to S_IFREG */ return 0; case S_IFDIR: return -EPERM; default: return -EINVAL; } } static long do_mknodat(int dfd, const char __user *filename, umode_t mode, unsigned int dev) { struct dentry *dentry; struct path path; int error; unsigned int lookup_flags = 0; error = may_mknod(mode); if (error) return error; retry: dentry = user_path_create(dfd, filename, &path, lookup_flags); if (IS_ERR(dentry)) return PTR_ERR(dentry); if (!IS_POSIXACL(path.dentry->d_inode)) mode &= ~current_umask(); error = security_path_mknod(&path, dentry, mode, dev); if (error) goto out; switch (mode & S_IFMT) { case 0: case S_IFREG: error = vfs_create(path.dentry->d_inode,dentry,mode,true); if (!error) ima_post_path_mknod(dentry); break; case S_IFCHR: case S_IFBLK: error = vfs_mknod(path.dentry->d_inode,dentry,mode, new_decode_dev(dev)); break; case S_IFIFO: case S_IFSOCK: error = vfs_mknod(path.dentry->d_inode,dentry,mode,0); break; } out: done_path_create(&path, dentry); if (retry_estale(error, lookup_flags)) { lookup_flags |= LOOKUP_REVAL; goto retry; } return error; } SYSCALL_DEFINE4(mknodat, int, dfd, const char __user *, filename, umode_t, mode, unsigned int, dev) { return do_mknodat(dfd, filename, mode, dev); } SYSCALL_DEFINE3(mknod, const char __user *, filename, umode_t, mode, unsigned, dev) { return do_mknodat(AT_FDCWD, filename, mode, dev); } int vfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) { int error = may_create(dir, dentry); unsigned max_links = dir->i_sb->s_max_links; if (error) return error; if (!dir->i_op->mkdir) return -EPERM; mode &= (S_IRWXUGO|S_ISVTX); error = security_inode_mkdir(dir, dentry, mode); if (error) return error; if (max_links && dir->i_nlink >= max_links) return -EMLINK; error = dir->i_op->mkdir(dir, dentry, mode); if (!error) fsnotify_mkdir(dir, dentry); return error; } EXPORT_SYMBOL(vfs_mkdir); static long do_mkdirat(int dfd, const char __user *pathname, umode_t mode) { struct dentry *dentry; struct path path; int error; unsigned int lookup_flags = LOOKUP_DIRECTORY; retry: dentry = user_path_create(dfd, pathname, &path, lookup_flags); if (IS_ERR(dentry)) return PTR_ERR(dentry); if (!IS_POSIXACL(path.dentry->d_inode)) mode &= ~current_umask(); error = security_path_mkdir(&path, dentry, mode); if (!error) error = vfs_mkdir(path.dentry->d_inode, dentry, mode); done_path_create(&path, dentry); if (retry_estale(error, lookup_flags)) { lookup_flags |= LOOKUP_REVAL; goto retry; } return error; } SYSCALL_DEFINE3(mkdirat, int, dfd, const char __user *, pathname, umode_t, mode) { return do_mkdirat(dfd, pathname, mode); } SYSCALL_DEFINE2(mkdir, const char __user *, pathname, umode_t, mode) { return do_mkdirat(AT_FDCWD, pathname, mode); } int vfs_rmdir(struct inode *dir, struct dentry *dentry) { int error = may_delete(dir, dentry, 1); if (error) return error; if (!dir->i_op->rmdir) return -EPERM; dget(dentry); inode_lock(dentry->d_inode); error = -EBUSY; if (is_local_mountpoint(dentry)) goto out; error = security_inode_rmdir(dir, dentry); if (error) goto out; error = dir->i_op->rmdir(dir, dentry); if (error) goto out; shrink_dcache_parent(dentry); dentry->d_inode->i_flags |= S_DEAD; dont_mount(dentry); detach_mounts(dentry); fsnotify_rmdir(dir, dentry); out: inode_unlock(dentry->d_inode); dput(dentry); if (!error) d_delete(dentry); return error; } EXPORT_SYMBOL(vfs_rmdir); long do_rmdir(int dfd, struct filename *name) { int error = 0; struct dentry *dentry; struct path path; struct qstr last; int type; unsigned int lookup_flags = 0; retry: name = filename_parentat(dfd, name, lookup_flags, &path, &last, &type); if (IS_ERR(name)) return PTR_ERR(name); switch (type) { case LAST_DOTDOT: error = -ENOTEMPTY; goto exit1; case LAST_DOT: error = -EINVAL; goto exit1; case LAST_ROOT: error = -EBUSY; goto exit1; } error = mnt_want_write(path.mnt); if (error) goto exit1; inode_lock_nested(path.dentry->d_inode, I_MUTEX_PARENT); dentry = __lookup_hash(&last, path.dentry, lookup_flags); error = PTR_ERR(dentry); if (IS_ERR(dentry)) goto exit2; if (!dentry->d_inode) { error = -ENOENT; goto exit3; } error = security_path_rmdir(&path, dentry); if (error) goto exit3; error = vfs_rmdir(path.dentry->d_inode, dentry); exit3: dput(dentry); exit2: inode_unlock(path.dentry->d_inode); mnt_drop_write(path.mnt); exit1: path_put(&path); if (retry_estale(error, lookup_flags)) { lookup_flags |= LOOKUP_REVAL; goto retry; } putname(name); return error; } SYSCALL_DEFINE1(rmdir, const char __user *, pathname) { return do_rmdir(AT_FDCWD, getname(pathname)); } /** * vfs_unlink - unlink a filesystem object * @dir: parent directory * @dentry: victim * @delegated_inode: returns victim inode, if the inode is delegated. * * The caller must hold dir->i_mutex. * * If vfs_unlink discovers a delegation, it will return -EWOULDBLOCK and * return a reference to the inode in delegated_inode. The caller * should then break the delegation on that inode and retry. Because * breaking a delegation may take a long time, the caller should drop * dir->i_mutex before doing so. * * Alternatively, a caller may pass NULL for delegated_inode. This may * be appropriate for callers that expect the underlying filesystem not * to be NFS exported. */ int vfs_unlink(struct inode *dir, struct dentry *dentry, struct inode **delegated_inode) { struct inode *target = dentry->d_inode; int error = may_delete(dir, dentry, 0); if (error) return error; if (!dir->i_op->unlink) return -EPERM; inode_lock(target); if (is_local_mountpoint(dentry)) error = -EBUSY; else { error = security_inode_unlink(dir, dentry); if (!error) { error = try_break_deleg(target, delegated_inode); if (error) goto out; error = dir->i_op->unlink(dir, dentry); if (!error) { dont_mount(dentry); detach_mounts(dentry); fsnotify_unlink(dir, dentry); } } } out: inode_unlock(target); /* We don't d_delete() NFS sillyrenamed files--they still exist. */ if (!error && !(dentry->d_flags & DCACHE_NFSFS_RENAMED)) { fsnotify_link_count(target); d_delete(dentry); } return error; } EXPORT_SYMBOL(vfs_unlink); /* * Make sure that the actual truncation of the file will occur outside its * directory's i_mutex. Truncate can take a long time if there is a lot of * writeout happening, and we don't want to prevent access to the directory * while waiting on the I/O. */ long do_unlinkat(int dfd, struct filename *name) { int error; struct dentry *dentry; struct path path; struct qstr last; int type; struct inode *inode = NULL; struct inode *delegated_inode = NULL; unsigned int lookup_flags = 0; retry: name = filename_parentat(dfd, name, lookup_flags, &path, &last, &type); if (IS_ERR(name)) return PTR_ERR(name); error = -EISDIR; if (type != LAST_NORM) goto exit1; error = mnt_want_write(path.mnt); if (error) goto exit1; retry_deleg: inode_lock_nested(path.dentry->d_inode, I_MUTEX_PARENT); dentry = __lookup_hash(&last, path.dentry, lookup_flags); error = PTR_ERR(dentry); if (!IS_ERR(dentry)) { /* Why not before? Because we want correct error value */ if (last.name[last.len]) goto slashes; inode = dentry->d_inode; if (d_is_negative(dentry)) goto slashes; ihold(inode); error = security_path_unlink(&path, dentry); if (error) goto exit2; error = vfs_unlink(path.dentry->d_inode, dentry, &delegated_inode); exit2: dput(dentry); } inode_unlock(path.dentry->d_inode); if (inode) iput(inode); /* truncate the inode here */ inode = NULL; if (delegated_inode) { error = break_deleg_wait(&delegated_inode); if (!error) goto retry_deleg; } mnt_drop_write(path.mnt); exit1: path_put(&path); if (retry_estale(error, lookup_flags)) { lookup_flags |= LOOKUP_REVAL; inode = NULL; goto retry; } putname(name); return error; slashes: if (d_is_negative(dentry)) error = -ENOENT; else if (d_is_dir(dentry)) error = -EISDIR; else error = -ENOTDIR; goto exit2; } SYSCALL_DEFINE3(unlinkat, int, dfd, const char __user *, pathname, int, flag) { if ((flag & ~AT_REMOVEDIR) != 0) return -EINVAL; if (flag & AT_REMOVEDIR) return do_rmdir(dfd, getname(pathname)); return do_unlinkat(dfd, getname(pathname)); } SYSCALL_DEFINE1(unlink, const char __user *, pathname) { return do_unlinkat(AT_FDCWD, getname(pathname)); } int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname) { int error = may_create(dir, dentry); if (error) return error; if (!dir->i_op->symlink) return -EPERM; error = security_inode_symlink(dir, dentry, oldname); if (error) return error; error = dir->i_op->symlink(dir, dentry, oldname); if (!error) fsnotify_create(dir, dentry); return error; } EXPORT_SYMBOL(vfs_symlink); static long do_symlinkat(const char __user *oldname, int newdfd, const char __user *newname) { int error; struct filename *from; struct dentry *dentry; struct path path; unsigned int lookup_flags = 0; from = getname(oldname); if (IS_ERR(from)) return PTR_ERR(from); retry: dentry = user_path_create(newdfd, newname, &path, lookup_flags); error = PTR_ERR(dentry); if (IS_ERR(dentry)) goto out_putname; error = security_path_symlink(&path, dentry, from->name); if (!error) error = vfs_symlink(path.dentry->d_inode, dentry, from->name); done_path_create(&path, dentry); if (retry_estale(error, lookup_flags)) { lookup_flags |= LOOKUP_REVAL; goto retry; } out_putname: putname(from); return error; } SYSCALL_DEFINE3(symlinkat, const char __user *, oldname, int, newdfd, const char __user *, newname) { return do_symlinkat(oldname, newdfd, newname); } SYSCALL_DEFINE2(symlink, const char __user *, oldname, const char __user *, newname) { return do_symlinkat(oldname, AT_FDCWD, newname); } /** * vfs_link - create a new link * @old_dentry: object to be linked * @dir: new parent * @new_dentry: where to create the new link * @delegated_inode: returns inode needing a delegation break * * The caller must hold dir->i_mutex * * If vfs_link discovers a delegation on the to-be-linked file in need * of breaking, it will return -EWOULDBLOCK and return a reference to the * inode in delegated_inode. The caller should then break the delegation * and retry. Because breaking a delegation may take a long time, the * caller should drop the i_mutex before doing so. * * Alternatively, a caller may pass NULL for delegated_inode. This may * be appropriate for callers that expect the underlying filesystem not * to be NFS exported. */ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry, struct inode **delegated_inode) { struct inode *inode = old_dentry->d_inode; unsigned max_links = dir->i_sb->s_max_links; int error; if (!inode) return -ENOENT; error = may_create(dir, new_dentry); if (error) return error; if (dir->i_sb != inode->i_sb) return -EXDEV; /* * A link to an append-only or immutable file cannot be created. */ if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) return -EPERM; /* * Updating the link count will likely cause i_uid and i_gid to * be writen back improperly if their true value is unknown to * the vfs. */ if (HAS_UNMAPPED_ID(inode)) return -EPERM; if (!dir->i_op->link) return -EPERM; if (S_ISDIR(inode->i_mode)) return -EPERM; error = security_inode_link(old_dentry, dir, new_dentry); if (error) return error; inode_lock(inode); /* Make sure we don't allow creating hardlink to an unlinked file */ if (inode->i_nlink == 0 && !(inode->i_state & I_LINKABLE)) error = -ENOENT; else if (max_links && inode->i_nlink >= max_links) error = -EMLINK; else { error = try_break_deleg(inode, delegated_inode); if (!error) error = dir->i_op->link(old_dentry, dir, new_dentry); } if (!error && (inode->i_state & I_LINKABLE)) { spin_lock(&inode->i_lock); inode->i_state &= ~I_LINKABLE; spin_unlock(&inode->i_lock); } inode_unlock(inode); if (!error) fsnotify_link(dir, inode, new_dentry); return error; } EXPORT_SYMBOL(vfs_link); /* * Hardlinks are often used in delicate situations. We avoid * security-related surprises by not following symlinks on the * newname. --KAB * * We don't follow them on the oldname either to be compatible * with linux 2.0, and to avoid hard-linking to directories * and other special files. --ADM */ static int do_linkat(int olddfd, const char __user *oldname, int newdfd, const char __user *newname, int flags) { struct dentry *new_dentry; struct path old_path, new_path; struct inode *delegated_inode = NULL; int how = 0; int error; if ((flags & ~(AT_SYMLINK_FOLLOW | AT_EMPTY_PATH)) != 0) return -EINVAL; /* * To use null names we require CAP_DAC_READ_SEARCH * This ensures that not everyone will be able to create * handlink using the passed filedescriptor. */ if (flags & AT_EMPTY_PATH) { if (!capable(CAP_DAC_READ_SEARCH)) return -ENOENT; how = LOOKUP_EMPTY; } if (flags & AT_SYMLINK_FOLLOW) how |= LOOKUP_FOLLOW; retry: error = user_path_at(olddfd, oldname, how, &old_path); if (error) return error; new_dentry = user_path_create(newdfd, newname, &new_path, (how & LOOKUP_REVAL)); error = PTR_ERR(new_dentry); if (IS_ERR(new_dentry)) goto out; error = -EXDEV; if (old_path.mnt != new_path.mnt) goto out_dput; error = may_linkat(&old_path); if (unlikely(error)) goto out_dput; error = security_path_link(old_path.dentry, &new_path, new_dentry); if (error) goto out_dput; error = vfs_link(old_path.dentry, new_path.dentry->d_inode, new_dentry, &delegated_inode); out_dput: done_path_create(&new_path, new_dentry); if (delegated_inode) { error = break_deleg_wait(&delegated_inode); if (!error) { path_put(&old_path); goto retry; } } if (retry_estale(error, how)) { path_put(&old_path); how |= LOOKUP_REVAL; goto retry; } out: path_put(&old_path); return error; } SYSCALL_DEFINE5(linkat, int, olddfd, const char __user *, oldname, int, newdfd, const char __user *, newname, int, flags) { return do_linkat(olddfd, oldname, newdfd, newname, flags); } SYSCALL_DEFINE2(link, const char __user *, oldname, const char __user *, newname) { return do_linkat(AT_FDCWD, oldname, AT_FDCWD, newname, 0); } /** * vfs_rename - rename a filesystem object * @old_dir: parent of source * @old_dentry: source * @new_dir: parent of destination * @new_dentry: destination * @delegated_inode: returns an inode needing a delegation break * @flags: rename flags * * The caller must hold multiple mutexes--see lock_rename()). * * If vfs_rename discovers a delegation in need of breaking at either * the source or destination, it will return -EWOULDBLOCK and return a * reference to the inode in delegated_inode. The caller should then * break the delegation and retry. Because breaking a delegation may * take a long time, the caller should drop all locks before doing * so. * * Alternatively, a caller may pass NULL for delegated_inode. This may * be appropriate for callers that expect the underlying filesystem not * to be NFS exported. * * The worst of all namespace operations - renaming directory. "Perverted" * doesn't even start to describe it. Somebody in UCB had a heck of a trip... * Problems: * * a) we can get into loop creation. * b) race potential - two innocent renames can create a loop together. * That's where 4.4 screws up. Current fix: serialization on * sb->s_vfs_rename_mutex. We might be more accurate, but that's another * story. * c) we have to lock _four_ objects - parents and victim (if it exists), * and source (if it is not a directory). * And that - after we got ->i_mutex on parents (until then we don't know * whether the target exists). Solution: try to be smart with locking * order for inodes. We rely on the fact that tree topology may change * only under ->s_vfs_rename_mutex _and_ that parent of the object we * move will be locked. Thus we can rank directories by the tree * (ancestors first) and rank all non-directories after them. * That works since everybody except rename does "lock parent, lookup, * lock child" and rename is under ->s_vfs_rename_mutex. * HOWEVER, it relies on the assumption that any object with ->lookup() * has no more than 1 dentry. If "hybrid" objects will ever appear, * we'd better make sure that there's no link(2) for them. * d) conversion from fhandle to dentry may come in the wrong moment - when * we are removing the target. Solution: we will have to grab ->i_mutex * in the fhandle_to_dentry code. [FIXME - current nfsfh.c relies on * ->i_mutex on parents, which works but leads to some truly excessive * locking]. */ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry, struct inode **delegated_inode, unsigned int flags) { int error; bool is_dir = d_is_dir(old_dentry); struct inode *source = old_dentry->d_inode; struct inode *target = new_dentry->d_inode; bool new_is_dir = false; unsigned max_links = new_dir->i_sb->s_max_links; struct name_snapshot old_name; if (source == target) return 0; error = may_delete(old_dir, old_dentry, is_dir); if (error) return error; if (!target) { error = may_create(new_dir, new_dentry); } else { new_is_dir = d_is_dir(new_dentry); if (!(flags & RENAME_EXCHANGE)) error = may_delete(new_dir, new_dentry, is_dir); else error = may_delete(new_dir, new_dentry, new_is_dir); } if (error) return error; if (!old_dir->i_op->rename) return -EPERM; /* * If we are going to change the parent - check write permissions, * we'll need to flip '..'. */ if (new_dir != old_dir) { if (is_dir) { error = inode_permission(source, MAY_WRITE); if (error) return error; } if ((flags & RENAME_EXCHANGE) && new_is_dir) { error = inode_permission(target, MAY_WRITE); if (error) return error; } } error = security_inode_rename(old_dir, old_dentry, new_dir, new_dentry, flags); if (error) return error; take_dentry_name_snapshot(&old_name, old_dentry); dget(new_dentry); if (!is_dir || (flags & RENAME_EXCHANGE)) lock_two_nondirectories(source, target); else if (target) inode_lock(target); error = -EBUSY; if (is_local_mountpoint(old_dentry) || is_local_mountpoint(new_dentry)) goto out; if (max_links && new_dir != old_dir) { error = -EMLINK; if (is_dir && !new_is_dir && new_dir->i_nlink >= max_links) goto out; if ((flags & RENAME_EXCHANGE) && !is_dir && new_is_dir && old_dir->i_nlink >= max_links) goto out; } if (!is_dir) { error = try_break_deleg(source, delegated_inode); if (error) goto out; } if (target && !new_is_dir) { error = try_break_deleg(target, delegated_inode); if (error) goto out; } error = old_dir->i_op->rename(old_dir, old_dentry, new_dir, new_dentry, flags); if (error) goto out; if (!(flags & RENAME_EXCHANGE) && target) { if (is_dir) { shrink_dcache_parent(new_dentry); target->i_flags |= S_DEAD; } dont_mount(new_dentry); detach_mounts(new_dentry); } if (!(old_dir->i_sb->s_type->fs_flags & FS_RENAME_DOES_D_MOVE)) { if (!(flags & RENAME_EXCHANGE)) d_move(old_dentry, new_dentry); else d_exchange(old_dentry, new_dentry); } out: if (!is_dir || (flags & RENAME_EXCHANGE)) unlock_two_nondirectories(source, target); else if (target) inode_unlock(target); dput(new_dentry); if (!error) { fsnotify_move(old_dir, new_dir, &old_name.name, is_dir, !(flags & RENAME_EXCHANGE) ? target : NULL, old_dentry); if (flags & RENAME_EXCHANGE) { fsnotify_move(new_dir, old_dir, &old_dentry->d_name, new_is_dir, NULL, new_dentry); } } release_dentry_name_snapshot(&old_name); return error; } EXPORT_SYMBOL(vfs_rename); static int do_renameat2(int olddfd, const char __user *oldname, int newdfd, const char __user *newname, unsigned int flags) { struct dentry *old_dentry, *new_dentry; struct dentry *trap; struct path old_path, new_path; struct qstr old_last, new_last; int old_type, new_type; struct inode *delegated_inode = NULL; struct filename *from; struct filename *to; unsigned int lookup_flags = 0, target_flags = LOOKUP_RENAME_TARGET; bool should_retry = false; int error; if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT)) return -EINVAL; if ((flags & (RENAME_NOREPLACE | RENAME_WHITEOUT)) && (flags & RENAME_EXCHANGE)) return -EINVAL; if (flags & RENAME_EXCHANGE) target_flags = 0; retry: from = filename_parentat(olddfd, getname(oldname), lookup_flags, &old_path, &old_last, &old_type); if (IS_ERR(from)) { error = PTR_ERR(from); goto exit; } to = filename_parentat(newdfd, getname(newname), lookup_flags, &new_path, &new_last, &new_type); if (IS_ERR(to)) { error = PTR_ERR(to); goto exit1; } error = -EXDEV; if (old_path.mnt != new_path.mnt) goto exit2; error = -EBUSY; if (old_type != LAST_NORM) goto exit2; if (flags & RENAME_NOREPLACE) error = -EEXIST; if (new_type != LAST_NORM) goto exit2; error = mnt_want_write(old_path.mnt); if (error) goto exit2; retry_deleg: trap = lock_rename(new_path.dentry, old_path.dentry); old_dentry = __lookup_hash(&old_last, old_path.dentry, lookup_flags); error = PTR_ERR(old_dentry); if (IS_ERR(old_dentry)) goto exit3; /* source must exist */ error = -ENOENT; if (d_is_negative(old_dentry)) goto exit4; new_dentry = __lookup_hash(&new_last, new_path.dentry, lookup_flags | target_flags); error = PTR_ERR(new_dentry); if (IS_ERR(new_dentry)) goto exit4; error = -EEXIST; if ((flags & RENAME_NOREPLACE) && d_is_positive(new_dentry)) goto exit5; if (flags & RENAME_EXCHANGE) { error = -ENOENT; if (d_is_negative(new_dentry)) goto exit5; if (!d_is_dir(new_dentry)) { error = -ENOTDIR; if (new_last.name[new_last.len]) goto exit5; } } /* unless the source is a directory trailing slashes give -ENOTDIR */ if (!d_is_dir(old_dentry)) { error = -ENOTDIR; if (old_last.name[old_last.len]) goto exit5; if (!(flags & RENAME_EXCHANGE) && new_last.name[new_last.len]) goto exit5; } /* source should not be ancestor of target */ error = -EINVAL; if (old_dentry == trap) goto exit5; /* target should not be an ancestor of source */ if (!(flags & RENAME_EXCHANGE)) error = -ENOTEMPTY; if (new_dentry == trap) goto exit5; error = security_path_rename(&old_path, old_dentry, &new_path, new_dentry, flags); if (error) goto exit5; error = vfs_rename(old_path.dentry->d_inode, old_dentry, new_path.dentry->d_inode, new_dentry, &delegated_inode, flags); exit5: dput(new_dentry); exit4: dput(old_dentry); exit3: unlock_rename(new_path.dentry, old_path.dentry); if (delegated_inode) { error = break_deleg_wait(&delegated_inode); if (!error) goto retry_deleg; } mnt_drop_write(old_path.mnt); exit2: if (retry_estale(error, lookup_flags)) should_retry = true; path_put(&new_path); putname(to); exit1: path_put(&old_path); putname(from); if (should_retry) { should_retry = false; lookup_flags |= LOOKUP_REVAL; goto retry; } exit: return error; } SYSCALL_DEFINE5(renameat2, int, olddfd, const char __user *, oldname, int, newdfd, const char __user *, newname, unsigned int, flags) { return do_renameat2(olddfd, oldname, newdfd, newname, flags); } SYSCALL_DEFINE4(renameat, int, olddfd, const char __user *, oldname, int, newdfd, const char __user *, newname) { return do_renameat2(olddfd, oldname, newdfd, newname, 0); } SYSCALL_DEFINE2(rename, const char __user *, oldname, const char __user *, newname) { return do_renameat2(AT_FDCWD, oldname, AT_FDCWD, newname, 0); } int readlink_copy(char __user *buffer, int buflen, const char *link) { int len = PTR_ERR(link); if (IS_ERR(link)) goto out; len = strlen(link); if (len > (unsigned) buflen) len = buflen; if (copy_to_user(buffer, link, len)) len = -EFAULT; out: return len; } /** * vfs_readlink - copy symlink body into userspace buffer * @dentry: dentry on which to get symbolic link * @buffer: user memory pointer * @buflen: size of buffer * * Does not touch atime. That's up to the caller if necessary * * Does not call security hook. */ int vfs_readlink(struct dentry *dentry, char __user *buffer, int buflen) { struct inode *inode = d_inode(dentry); DEFINE_DELAYED_CALL(done); const char *link; int res; if (unlikely(!(inode->i_opflags & IOP_DEFAULT_READLINK))) { if (unlikely(inode->i_op->readlink)) return inode->i_op->readlink(dentry, buffer, buflen); if (!d_is_symlink(dentry)) return -EINVAL; spin_lock(&inode->i_lock); inode->i_opflags |= IOP_DEFAULT_READLINK; spin_unlock(&inode->i_lock); } link = READ_ONCE(inode->i_link); if (!link) { link = inode->i_op->get_link(dentry, inode, &done); if (IS_ERR(link)) return PTR_ERR(link); } res = readlink_copy(buffer, buflen, link); do_delayed_call(&done); return res; } EXPORT_SYMBOL(vfs_readlink); /** * vfs_get_link - get symlink body * @dentry: dentry on which to get symbolic link * @done: caller needs to free returned data with this * * Calls security hook and i_op->get_link() on the supplied inode. * * It does not touch atime. That's up to the caller if necessary. * * Does not work on "special" symlinks like /proc/$$/fd/N */ const char *vfs_get_link(struct dentry *dentry, struct delayed_call *done) { const char *res = ERR_PTR(-EINVAL); struct inode *inode = d_inode(dentry); if (d_is_symlink(dentry)) { res = ERR_PTR(security_inode_readlink(dentry)); if (!res) res = inode->i_op->get_link(dentry, inode, done); } return res; } EXPORT_SYMBOL(vfs_get_link); /* get the link contents into pagecache */ const char *page_get_link(struct dentry *dentry, struct inode *inode, struct delayed_call *callback) { char *kaddr; struct page *page; struct address_space *mapping = inode->i_mapping; if (!dentry) { page = find_get_page(mapping, 0); if (!page) return ERR_PTR(-ECHILD); if (!PageUptodate(page)) { put_page(page); return ERR_PTR(-ECHILD); } } else { page = read_mapping_page(mapping, 0, NULL); if (IS_ERR(page)) return (char*)page; } set_delayed_call(callback, page_put_link, page); BUG_ON(mapping_gfp_mask(mapping) & __GFP_HIGHMEM); kaddr = page_address(page); nd_terminate_link(kaddr, inode->i_size, PAGE_SIZE - 1); return kaddr; } EXPORT_SYMBOL(page_get_link); void page_put_link(void *arg) { put_page(arg); } EXPORT_SYMBOL(page_put_link); int page_readlink(struct dentry *dentry, char __user *buffer, int buflen) { DEFINE_DELAYED_CALL(done); int res = readlink_copy(buffer, buflen, page_get_link(dentry, d_inode(dentry), &done)); do_delayed_call(&done); return res; } EXPORT_SYMBOL(page_readlink); /* * The nofs argument instructs pagecache_write_begin to pass AOP_FLAG_NOFS */ int __page_symlink(struct inode *inode, const char *symname, int len, int nofs) { struct address_space *mapping = inode->i_mapping; struct page *page; void *fsdata; int err; unsigned int flags = 0; if (nofs) flags |= AOP_FLAG_NOFS; retry: err = pagecache_write_begin(NULL, mapping, 0, len-1, flags, &page, &fsdata); if (err) goto fail; memcpy(page_address(page), symname, len-1); err = pagecache_write_end(NULL, mapping, 0, len-1, len-1, page, fsdata); if (err < 0) goto fail; if (err < len-1) goto retry; mark_inode_dirty(inode); return 0; fail: return err; } EXPORT_SYMBOL(__page_symlink); int page_symlink(struct inode *inode, const char *symname, int len) { return __page_symlink(inode, symname, len, !mapping_gfp_constraint(inode->i_mapping, __GFP_FS)); } EXPORT_SYMBOL(page_symlink); const struct inode_operations page_symlink_inode_operations = { .get_link = page_get_link, }; EXPORT_SYMBOL(page_symlink_inode_operations);
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 /* SPDX-License-Identifier: GPL-2.0 */ #ifndef _LINUX_SCHED_CLOCK_H #define _LINUX_SCHED_CLOCK_H #include <linux/smp.h> /* * Do not use outside of architecture code which knows its limitations. * * sched_clock() has no promise of monotonicity or bounded drift between * CPUs, use (which you should not) requires disabling IRQs. * * Please use one of the three interfaces below. */ extern unsigned long long notrace sched_clock(void); /* * See the comment in kernel/sched/clock.c */ extern u64 running_clock(void); extern u64 sched_clock_cpu(int cpu); extern void sched_clock_init(void); #ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK static inline void sched_clock_tick(void) { } static inline void clear_sched_clock_stable(void) { } static inline void sched_clock_idle_sleep_event(void) { } static inline void sched_clock_idle_wakeup_event(void) { } static inline u64 cpu_clock(int cpu) { return sched_clock(); } static inline u64 local_clock(void) { return sched_clock(); } #else extern int sched_clock_stable(void); extern void clear_sched_clock_stable(void); /* * When sched_clock_stable(), __sched_clock_offset provides the offset * between local_clock() and sched_clock(). */ extern u64 __sched_clock_offset; extern void sched_clock_tick(void); extern void sched_clock_tick_stable(void); extern void sched_clock_idle_sleep_event(void); extern void sched_clock_idle_wakeup_event(void); /* * As outlined in clock.c, provides a fast, high resolution, nanosecond * time source that is monotonic per cpu argument and has bounded drift * between cpus. * * ######################### BIG FAT WARNING ########################## * # when comparing cpu_clock(i) to cpu_clock(j) for i != j, time can # * # go backwards !! # * #################################################################### */ static inline u64 cpu_clock(int cpu) { return sched_clock_cpu(cpu); } static inline u64 local_clock(void) { return sched_clock_cpu(raw_smp_processor_id()); } #endif #ifdef CONFIG_IRQ_TIME_ACCOUNTING /* * An i/f to runtime opt-in for irq time accounting based off of sched_clock. * The reason for this explicit opt-in is not to have perf penalty with * slow sched_clocks. */ extern void enable_sched_clock_irqtime(void); extern void disable_sched_clock_irqtime(void); #else static inline void enable_sched_clock_irqtime(void) {} static inline void disable_sched_clock_irqtime(void) {} #endif #endif /* _LINUX_SCHED_CLOCK_H */
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 /* SPDX-License-Identifier: GPL-2.0 */ #ifndef _LINUX_BYTEORDER_GENERIC_H #define _LINUX_BYTEORDER_GENERIC_H /* * linux/byteorder/generic.h * Generic Byte-reordering support * * The "... p" macros, like le64_to_cpup, can be used with pointers * to unaligned data, but there will be a performance penalty on * some architectures. Use get_unaligned for unaligned data. * * Francois-Rene Rideau <fare@tunes.org> 19970707 * gathered all the good ideas from all asm-foo/byteorder.h into one file, * cleaned them up. * I hope it is compliant with non-GCC compilers. * I decided to put __BYTEORDER_HAS_U64__ in byteorder.h, * because I wasn't sure it would be ok to put it in types.h * Upgraded it to 2.1.43 * Francois-Rene Rideau <fare@tunes.org> 19971012 * Upgraded it to 2.1.57 * to please Linus T., replaced huge #ifdef's between little/big endian * by nestedly #include'd files. * Francois-Rene Rideau <fare@tunes.org> 19971205 * Made it to 2.1.71; now a facelift: * Put files under include/linux/byteorder/ * Split swab from generic support. * * TODO: * = Regular kernel maintainers could also replace all these manual * byteswap macros that remain, disseminated among drivers, * after some grep or the sources... * = Linus might want to rename all these macros and files to fit his taste, * to fit his personal naming scheme. * = it seems that a few drivers would also appreciate * nybble swapping support... * = every architecture could add their byteswap macro in asm/byteorder.h * see how some architectures already do (i386, alpha, ppc, etc) * = cpu_to_beXX and beXX_to_cpu might some day need to be well * distinguished throughout the kernel. This is not the case currently, * since little endian, big endian, and pdp endian machines needn't it. * But this might be the case for, say, a port of Linux to 20/21 bit * architectures (and F21 Linux addict around?). */ /* * The following macros are to be defined by <asm/byteorder.h>: * * Conversion of long and short int between network and host format * ntohl(__u32 x) * ntohs(__u16 x) * htonl(__u32 x) * htons(__u16 x) * It seems that some programs (which? where? or perhaps a standard? POSIX?) * might like the above to be functions, not macros (why?). * if that's true, then detect them, and take measures. * Anyway, the measure is: define only ___ntohl as a macro instead, * and in a separate file, have * unsigned long inline ntohl(x){return ___ntohl(x);} * * The same for constant arguments * __constant_ntohl(__u32 x) * __constant_ntohs(__u16 x) * __constant_htonl(__u32 x) * __constant_htons(__u16 x) * * Conversion of XX-bit integers (16- 32- or 64-) * between native CPU format and little/big endian format * 64-bit stuff only defined for proper architectures * cpu_to_[bl]eXX(__uXX x) * [bl]eXX_to_cpu(__uXX x) * * The same, but takes a pointer to the value to convert * cpu_to_[bl]eXXp(__uXX x) * [bl]eXX_to_cpup(__uXX x) * * The same, but change in situ * cpu_to_[bl]eXXs(__uXX x) * [bl]eXX_to_cpus(__uXX x) * * See asm-foo/byteorder.h for examples of how to provide * architecture-optimized versions * */ #define cpu_to_le64 __cpu_to_le64 #define le64_to_cpu __le64_to_cpu #define cpu_to_le32 __cpu_to_le32 #define le32_to_cpu __le32_to_cpu #define cpu_to_le16 __cpu_to_le16 #define le16_to_cpu __le16_to_cpu #define cpu_to_be64 __cpu_to_be64 #define be64_to_cpu __be64_to_cpu #define cpu_to_be32 __cpu_to_be32 #define be32_to_cpu __be32_to_cpu #define cpu_to_be16 __cpu_to_be16 #define be16_to_cpu __be16_to_cpu #define cpu_to_le64p __cpu_to_le64p #define le64_to_cpup __le64_to_cpup #define cpu_to_le32p __cpu_to_le32p #define le32_to_cpup __le32_to_cpup #define cpu_to_le16p __cpu_to_le16p #define le16_to_cpup __le16_to_cpup #define cpu_to_be64p __cpu_to_be64p #define be64_to_cpup __be64_to_cpup #define cpu_to_be32p __cpu_to_be32p #define be32_to_cpup __be32_to_cpup #define cpu_to_be16p __cpu_to_be16p #define be16_to_cpup __be16_to_cpup #define cpu_to_le64s __cpu_to_le64s #define le64_to_cpus __le64_to_cpus #define cpu_to_le32s __cpu_to_le32s #define le32_to_cpus __le32_to_cpus #define cpu_to_le16s __cpu_to_le16s #define le16_to_cpus __le16_to_cpus #define cpu_to_be64s __cpu_to_be64s #define be64_to_cpus __be64_to_cpus #define cpu_to_be32s __cpu_to_be32s #define be32_to_cpus __be32_to_cpus #define cpu_to_be16s __cpu_to_be16s #define be16_to_cpus __be16_to_cpus /* * They have to be macros in order to do the constant folding * correctly - if the argument passed into a inline function * it is no longer constant according to gcc.. */ #undef ntohl #undef ntohs #undef htonl #undef htons #define ___htonl(x) __cpu_to_be32(x) #define ___htons(x) __cpu_to_be16(x) #define ___ntohl(x) __be32_to_cpu(x) #define ___ntohs(x) __be16_to_cpu(x) #define htonl(x) ___htonl(x) #define ntohl(x) ___ntohl(x) #define htons(x) ___htons(x) #define ntohs(x) ___ntohs(x) static inline void le16_add_cpu(__le16 *var, u16 val) { *var = cpu_to_le16(le16_to_cpu(*var) + val); } static inline void le32_add_cpu(__le32 *var, u32 val) { *var = cpu_to_le32(le32_to_cpu(*var) + val); } static inline void le64_add_cpu(__le64 *var, u64 val) { *var = cpu_to_le64(le64_to_cpu(*var) + val); } /* XXX: this stuff can be optimized */ static inline void le32_to_cpu_array(u32 *buf, unsigned int words) { while (words--) { __le32_to_cpus(buf); buf++; } } static inline void cpu_to_le32_array(u32 *buf, unsigned int words) { while (words--) { __cpu_to_le32s(buf); buf++; } } static inline void be16_add_cpu(__be16 *var, u16 val) { *var = cpu_to_be16(be16_to_cpu(*var) + val); } static inline void be32_add_cpu(__be32 *var, u32 val) { *var = cpu_to_be32(be32_to_cpu(*var) + val); } static inline void be64_add_cpu(__be64 *var, u64 val) { *var = cpu_to_be64(be64_to_cpu(*var) + val); } static inline void cpu_to_be32_array(__be32 *dst, const u32 *src, size_t len) { int i; for (i = 0; i < len; i++) dst[i] = cpu_to_be32(src[i]); } static inline void be32_to_cpu_array(u32 *dst, const __be32 *src, size_t len) { int i; for (i = 0; i < len; i++) dst[i] = be32_to_cpu(src[i]); } #endif /* _LINUX_BYTEORDER_GENERIC_H */
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 /* SPDX-License-Identifier: GPL-2.0 */ #ifndef RQ_QOS_H #define RQ_QOS_H #include <linux/kernel.h> #include <linux/blkdev.h> #include <linux/blk_types.h> #include <linux/atomic.h> #include <linux/wait.h> #include <linux/blk-mq.h> #include "blk-mq-debugfs.h" struct blk_mq_debugfs_attr; enum rq_qos_id { RQ_QOS_WBT, RQ_QOS_LATENCY, RQ_QOS_COST, }; struct rq_wait { wait_queue_head_t wait; atomic_t inflight; }; struct rq_qos { struct rq_qos_ops *ops; struct request_queue *q; enum rq_qos_id id; struct rq_qos *next; #ifdef CONFIG_BLK_DEBUG_FS struct dentry *debugfs_dir; #endif }; struct rq_qos_ops { void (*throttle)(struct rq_qos *, struct bio *); void (*track)(struct rq_qos *, struct request *, struct bio *); void (*merge)(struct rq_qos *, struct request *, struct bio *); void (*issue)(struct rq_qos *, struct request *); void (*requeue)(struct rq_qos *, struct request *); void (*done)(struct rq_qos *, struct request *); void (*done_bio)(struct rq_qos *, struct bio *); void (*cleanup)(struct rq_qos *, struct bio *); void (*queue_depth_changed)(struct rq_qos *); void (*exit)(struct rq_qos *); const struct blk_mq_debugfs_attr *debugfs_attrs; }; struct rq_depth { unsigned int max_depth; int scale_step; bool scaled_max; unsigned int queue_depth; unsigned int default_depth; }; static inline struct rq_qos *rq_qos_id(struct request_queue *q, enum rq_qos_id id) { struct rq_qos *rqos; for (rqos = q->rq_qos; rqos; rqos = rqos->next) { if (rqos->id == id) break; } return rqos; } static inline struct rq_qos *wbt_rq_qos(struct request_queue *q) { return rq_qos_id(q, RQ_QOS_WBT); } static inline struct rq_qos *blkcg_rq_qos(struct request_queue *q) { return rq_qos_id(q, RQ_QOS_LATENCY); } static inline const char *rq_qos_id_to_name(enum rq_qos_id id) { switch (id) { case RQ_QOS_WBT: return "wbt"; case RQ_QOS_LATENCY: return "latency"; case RQ_QOS_COST: return "cost"; } return "unknown"; } static inline void rq_wait_init(struct rq_wait *rq_wait) { atomic_set(&rq_wait->inflight, 0); init_waitqueue_head(&rq_wait->wait); } static inline void rq_qos_add(struct request_queue *q, struct rq_qos *rqos) { /* * No IO can be in-flight when adding rqos, so freeze queue, which * is fine since we only support rq_qos for blk-mq queue. * * Reuse ->queue_lock for protecting against other concurrent * rq_qos adding/deleting */ blk_mq_freeze_queue(q); spin_lock_irq(&q->queue_lock); rqos->next = q->rq_qos; q->rq_qos = rqos; spin_unlock_irq(&q->queue_lock); blk_mq_unfreeze_queue(q); if (rqos->ops->debugfs_attrs) blk_mq_debugfs_register_rqos(rqos); } static inline void rq_qos_del(struct request_queue *q, struct rq_qos *rqos) { struct rq_qos **cur; /* * See comment in rq_qos_add() about freezing queue & using * ->queue_lock. */ blk_mq_freeze_queue(q); spin_lock_irq(&q->queue_lock); for (cur = &q->rq_qos; *cur; cur = &(*cur)->next) { if (*cur == rqos) { *cur = rqos->next; break; } } spin_unlock_irq(&q->queue_lock); blk_mq_unfreeze_queue(q); blk_mq_debugfs_unregister_rqos(rqos); } typedef bool (acquire_inflight_cb_t)(struct rq_wait *rqw, void *private_data); typedef void (cleanup_cb_t)(struct rq_wait *rqw, void *private_data); void rq_qos_wait(struct rq_wait *rqw, void *private_data, acquire_inflight_cb_t *acquire_inflight_cb, cleanup_cb_t *cleanup_cb); bool rq_wait_inc_below(struct rq_wait *rq_wait, unsigned int limit); bool rq_depth_scale_up(struct rq_depth *rqd); bool rq_depth_scale_down(struct rq_depth *rqd, bool hard_throttle); bool rq_depth_calc_max_depth(struct rq_depth *rqd); void __rq_qos_cleanup(struct rq_qos *rqos, struct bio *bio); void __rq_qos_done(struct rq_qos *rqos, struct request *rq); void __rq_qos_issue(struct rq_qos *rqos, struct request *rq); void __rq_qos_requeue(struct rq_qos *rqos, struct request *rq); void __rq_qos_throttle(struct rq_qos *rqos, struct bio *bio); void __rq_qos_track(struct rq_qos *rqos, struct request *rq, struct bio *bio); void __rq_qos_merge(struct rq_qos *rqos, struct request *rq, struct bio *bio); void __rq_qos_done_bio(struct rq_qos *rqos, struct bio *bio); void __rq_qos_queue_depth_changed(struct rq_qos *rqos); static inline void rq_qos_cleanup(struct request_queue *q, struct bio *bio) { if (q->rq_qos) __rq_qos_cleanup(q->rq_qos, bio); } static inline void rq_qos_done(struct request_queue *q, struct request *rq) { if (q->rq_qos) __rq_qos_done(q->rq_qos, rq); } static inline void rq_qos_issue(struct request_queue *q, struct request *rq) { if (q->rq_qos) __rq_qos_issue(q->rq_qos, rq); } static inline void rq_qos_requeue(struct request_queue *q, struct request *rq) { if (q->rq_qos) __rq_qos_requeue(q->rq_qos, rq); } static inline void rq_qos_done_bio(struct request_queue *q, struct bio *bio) { if (q->rq_qos) __rq_qos_done_bio(q->rq_qos, bio); } static inline void rq_qos_throttle(struct request_queue *q, struct bio *bio) { /* * BIO_TRACKED lets controllers know that a bio went through the * normal rq_qos path. */ bio_set_flag(bio, BIO_TRACKED); if (q->rq_qos) __rq_qos_throttle(q->rq_qos, bio); } static inline void rq_qos_track(struct request_queue *q, struct request *rq, struct bio *bio) { if (q->rq_qos) __rq_qos_track(q->rq_qos, rq, bio); } static inline void rq_qos_merge(struct request_queue *q, struct request *rq, struct bio *bio) { if (q->rq_qos) __rq_qos_merge(q->rq_qos, rq, bio); } static inline void rq_qos_queue_depth_changed(struct request_queue *q) { if (q->rq_qos) __rq_qos_queue_depth_changed(q->rq_qos); } voi