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 /* SPDX-License-Identifier: GPL-2.0-or-later */ /* * ALSA sequencer Memory Manager * Copyright (c) 1998 by Frank van de Pol <fvdpol@coil.demon.nl> */ #ifndef __SND_SEQ_MEMORYMGR_H #define __SND_SEQ_MEMORYMGR_H #include <sound/seq_kernel.h> #include <linux/poll.h> struct snd_info_buffer; /* container for sequencer event (internal use) */ struct snd_seq_event_cell { struct snd_seq_event event; struct snd_seq_pool *pool; /* used pool */ struct snd_seq_event_cell *next; /* next cell */ }; /* design note: the pool is a contiguous block of memory, if we dynamicly want to add additional cells to the pool be better store this in another pool as we need to know the base address of the pool when releasing memory. */ struct snd_seq_pool { struct snd_seq_event_cell *ptr; /* pointer to first event chunk */ struct snd_seq_event_cell *free; /* pointer to the head of the free list */ int total_elements; /* pool size actually allocated */ atomic_t counter; /* cells free */ int size; /* pool size to be allocated */ int room; /* watermark for sleep/wakeup */ int closing; /* statistics */ int max_used; int event_alloc_nopool; int event_alloc_failures; int event_alloc_success; /* Write locking */ wait_queue_head_t output_sleep; /* Pool lock */ spinlock_t lock; }; void snd_seq_cell_free(struct snd_seq_event_cell *cell); int snd_seq_event_dup(struct snd_seq_pool *pool, struct snd_seq_event *event, struct snd_seq_event_cell **cellp, int nonblock, struct file *file, struct mutex *mutexp); /* return number of unused (free) cells */ static inline int snd_seq_unused_cells(struct snd_seq_pool *pool) { return pool ? pool->total_elements - atomic_read(&pool->counter) : 0; } /* return total number of allocated cells */ static inline int snd_seq_total_cells(struct snd_seq_pool *pool) { return pool ? pool->total_elements : 0; } /* init pool - allocate events */ int snd_seq_pool_init(struct snd_seq_pool *pool); /* done pool - free events */ void snd_seq_pool_mark_closing(struct snd_seq_pool *pool); int snd_seq_pool_done(struct snd_seq_pool *pool); /* create pool */ struct snd_seq_pool *snd_seq_pool_new(int poolsize); /* remove pool */ int snd_seq_pool_delete(struct snd_seq_pool **pool); /* polling */ int snd_seq_pool_poll_wait(struct snd_seq_pool *pool, struct file *file, poll_table *wait); void snd_seq_info_pool(struct snd_info_buffer *buffer, struct snd_seq_pool *pool, char *space); #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 /* SPDX-License-Identifier: GPL-2.0-or-later */ /* Red Black Trees (C) 1999 Andrea Arcangeli <andrea@suse.de> (C) 2002 David Woodhouse <dwmw2@infradead.org> (C) 2012 Michel Lespinasse <walken@google.com> linux/include/linux/rbtree_augmented.h */ #ifndef _LINUX_RBTREE_AUGMENTED_H #define _LINUX_RBTREE_AUGMENTED_H #include <linux/compiler.h> #include <linux/rbtree.h> #include <linux/rcupdate.h> /* * Please note - only struct rb_augment_callbacks and the prototypes for * rb_insert_augmented() and rb_erase_augmented() are intended to be public. * The rest are implementation details you are not expected to depend on. * * See Documentation/core-api/rbtree.rst for documentation and samples. */ struct rb_augment_callbacks { void (*propagate)(struct rb_node *node, struct rb_node *stop); void (*copy)(struct rb_node *old, struct rb_node *new); void (*rotate)(struct rb_node *old, struct rb_node *new); }; extern void __rb_insert_augmented(struct rb_node *node, struct rb_root *root, void (*augment_rotate)(struct rb_node *old, struct rb_node *new)); /* * Fixup the rbtree and update the augmented information when rebalancing. * * On insertion, the user must update the augmented information on the path * leading to the inserted node, then call rb_link_node() as usual and * rb_insert_augmented() instead of the usual rb_insert_color() call. * If rb_insert_augmented() rebalances the rbtree, it will callback into * a user provided function to update the augmented information on the * affected subtrees. */ static inline void rb_insert_augmented(struct rb_node *node, struct rb_root *root, const struct rb_augment_callbacks *augment) { __rb_insert_augmented(node, root, augment->rotate); } static inline void rb_insert_augmented_cached(struct rb_node *node, struct rb_root_cached *root, bool newleft, const struct rb_augment_callbacks *augment) { if (newleft) root->rb_leftmost = node; rb_insert_augmented(node, &root->rb_root, augment); } /* * Template for declaring augmented rbtree callbacks (generic case) * * RBSTATIC: 'static' or empty * RBNAME: name of the rb_augment_callbacks structure * RBSTRUCT: struct type of the tree nodes * RBFIELD: name of struct rb_node field within RBSTRUCT * RBAUGMENTED: name of field within RBSTRUCT holding data for subtree * RBCOMPUTE: name of function that recomputes the RBAUGMENTED data */ #define RB_DECLARE_CALLBACKS(RBSTATIC, RBNAME, \ RBSTRUCT, RBFIELD, RBAUGMENTED, RBCOMPUTE) \ static inline void \ RBNAME ## _propagate(struct rb_node *rb, struct rb_node *stop) \ { \ while (rb != stop) { \ RBSTRUCT *node = rb_entry(rb, RBSTRUCT, RBFIELD); \ if (RBCOMPUTE(node, true)) \ break; \ rb = rb_parent(&node->RBFIELD); \ } \ } \ static inline void \ RBNAME ## _copy(struct rb_node *rb_old, struct rb_node *rb_new) \ { \ RBSTRUCT *old = rb_entry(rb_old, RBSTRUCT, RBFIELD); \ RBSTRUCT *new = rb_entry(rb_new, RBSTRUCT, RBFIELD); \ new->RBAUGMENTED = old->RBAUGMENTED; \ } \ static void \ RBNAME ## _rotate(struct rb_node *rb_old, struct rb_node *rb_new) \ { \ RBSTRUCT *old = rb_entry(rb_old, RBSTRUCT, RBFIELD); \ RBSTRUCT *new = rb_entry(rb_new, RBSTRUCT, RBFIELD); \ new->RBAUGMENTED = old->RBAUGMENTED; \ RBCOMPUTE(old, false); \ } \ RBSTATIC const struct rb_augment_callbacks RBNAME = { \ .propagate = RBNAME ## _propagate, \ .copy = RBNAME ## _copy, \ .rotate = RBNAME ## _rotate \ }; /* * Template for declaring augmented rbtree callbacks, * computing RBAUGMENTED scalar as max(RBCOMPUTE(node)) for all subtree nodes. * * RBSTATIC: 'static' or empty * RBNAME: name of the rb_augment_callbacks structure * RBSTRUCT: struct type of the tree nodes * RBFIELD: name of struct rb_node field within RBSTRUCT * RBTYPE: type of the RBAUGMENTED field * RBAUGMENTED: name of RBTYPE field within RBSTRUCT holding data for subtree * RBCOMPUTE: name of function that returns the per-node RBTYPE scalar */ #define RB_DECLARE_CALLBACKS_MAX(RBSTATIC, RBNAME, RBSTRUCT, RBFIELD, \ RBTYPE, RBAUGMENTED, RBCOMPUTE) \ static inline bool RBNAME ## _compute_max(RBSTRUCT *node, bool exit) \ { \ RBSTRUCT *child; \ RBTYPE max = RBCOMPUTE(node); \ if (node->RBFIELD.rb_left) { \ child = rb_entry(node->RBFIELD.rb_left, RBSTRUCT, RBFIELD); \ if (child->RBAUGMENTED > max) \ max = child->RBAUGMENTED; \ } \ if (node->RBFIELD.rb_right) { \ child = rb_entry(node->RBFIELD.rb_right, RBSTRUCT, RBFIELD); \ if (child->RBAUGMENTED > max) \ max = child->RBAUGMENTED; \ } \ if (exit && node->RBAUGMENTED == max) \ return true; \ node->RBAUGMENTED = max; \ return false; \ } \ RB_DECLARE_CALLBACKS(RBSTATIC, RBNAME, \ RBSTRUCT, RBFIELD, RBAUGMENTED, RBNAME ## _compute_max) #define RB_RED 0 #define RB_BLACK 1 #define __rb_parent(pc) ((struct rb_node *)(pc & ~3)) #define __rb_color(pc) ((pc) & 1) #define __rb_is_black(pc) __rb_color(pc) #define __rb_is_red(pc) (!__rb_color(pc)) #define rb_color(rb) __rb_color((rb)->__rb_parent_color) #define rb_is_red(rb) __rb_is_red((rb)->__rb_parent_color) #define rb_is_black(rb) __rb_is_black((rb)->__rb_parent_color) static inline void rb_set_parent(struct rb_node *rb, struct rb_node *p) { rb->__rb_parent_color = rb_color(rb) | (unsigned long)p; } static inline void rb_set_parent_color(struct rb_node *rb, struct rb_node *p, int color) { rb->__rb_parent_color = (unsigned long)p | color; } static inline void __rb_change_child(struct rb_node *old, struct rb_node *new, struct rb_node *parent, struct rb_root *root) { if (parent) { if (parent->rb_left == old) WRITE_ONCE(parent->rb_left, new); else WRITE_ONCE(parent->rb_right, new); } else WRITE_ONCE(root->rb_node, new); } static inline void __rb_change_child_rcu(struct rb_node *old, struct rb_node *new, struct rb_node *parent, struct rb_root *root) { if (parent) { if (parent->rb_left == old) rcu_assign_pointer(parent->rb_left, new); else rcu_assign_pointer(parent->rb_right, new); } else rcu_assign_pointer(root->rb_node, new); } extern void __rb_erase_color(struct rb_node *parent, struct rb_root *root, void (*augment_rotate)(struct rb_node *old, struct rb_node *new)); static __always_inline struct rb_node * __rb_erase_augmented(struct rb_node *node, struct rb_root *root, const struct rb_augment_callbacks *augment) { struct rb_node *child = node->rb_right; struct rb_node *tmp = node->rb_left; struct rb_node *parent, *rebalance; unsigned long pc; if (!tmp) { /* * Case 1: node to erase has no more than 1 child (easy!) * * Note that if there is one child it must be red due to 5) * and node must be black due to 4). We adjust colors locally * so as to bypass __rb_erase_color() later on. */ pc = node->__rb_parent_color; parent = __rb_parent(pc); __rb_change_child(node, child, parent, root); if (child) { child->__rb_parent_color = pc; rebalance = NULL; } else rebalance = __rb_is_black(pc) ? parent : NULL; tmp = parent; } else if (!child) { /* Still case 1, but this time the child is node->rb_left */ tmp->__rb_parent_color = pc = node->__rb_parent_color; parent = __rb_parent(pc); __rb_change_child(node, tmp, parent, root); rebalance = NULL; tmp = parent; } else { struct rb_node *successor = child, *child2; tmp = child->rb_left; if (!tmp) { /* * Case 2: node's successor is its right child * * (n) (s) * / \ / \ * (x) (s) -> (x) (c) * \ * (c) */ parent = successor; child2 = successor->rb_right; augment->copy(node, successor); } else { /* * Case 3: node's successor is leftmost under * node's right child subtree * * (n) (s) * / \ / \ * (x) (y) -> (x) (y) * / / * (p) (p) * / / * (s) (c) * \ * (c) */ do { parent = successor; successor = tmp; tmp = tmp->rb_left; } while (tmp); child2 = successor->rb_right; WRITE_ONCE(parent->rb_left, child2); WRITE_ONCE(successor->rb_right, child); rb_set_parent(child, successor); augment->copy(node, successor); augment->propagate(parent, successor); } tmp = node->rb_left; WRITE_ONCE(successor->rb_left, tmp); rb_set_parent(tmp, successor); pc = node->__rb_parent_color; tmp = __rb_parent(pc); __rb_change_child(node, successor, tmp, root); if (child2) { rb_set_parent_color(child2, parent, RB_BLACK); rebalance = NULL; } else { rebalance = rb_is_black(successor) ? parent : NULL; } successor->__rb_parent_color = pc; tmp = successor; } augment->propagate(tmp, NULL); return rebalance; } static __always_inline void rb_erase_augmented(struct rb_node *node, struct rb_root *root, const struct rb_augment_callbacks *augment) { struct rb_node *rebalance = __rb_erase_augmented(node, root, augment); if (rebalance) __rb_erase_color(rebalance, root, augment->rotate); } static __always_inline void rb_erase_augmented_cached(struct rb_node *node, struct rb_root_cached *root, const struct rb_augment_callbacks *augment) { if (root->rb_leftmost == node) root->rb_leftmost = rb_next(node); rb_erase_augmented(node, &root->rb_root, augment); } #endif /* _LINUX_RBTREE_AUGMENTED_H */
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2821 2822 2823 2824 2825 2826 2827 2828 2829 2830 2831 2832 2833 2834 2835 2836 2837 2838 2839 2840 2841 2842 2843 2844 2845 2846 2847 2848 2849 2850 2851 2852 2853 2854 2855 2856 2857 2858 2859 2860 2861 2862 2863 2864 2865 2866 2867 2868 2869 2870 2871 2872 2873 2874 2875 2876 2877 2878 2879 2880 2881 2882 2883 2884 2885 2886 2887 2888 2889 2890 2891 2892 2893 2894 2895 2896 2897 2898 2899 2900 2901 2902 2903 2904 2905 2906 2907 2908 2909 2910 2911 2912 2913 2914 2915 2916 2917 2918 2919 2920 2921 2922 2923 2924 2925 2926 2927 2928 2929 2930 2931 2932 2933 2934 2935 2936 2937 2938 2939 2940 2941 2942 2943 2944 2945 2946 2947 2948 2949 2950 2951 2952 2953 2954 2955 2956 2957 2958 2959 2960 2961 2962 2963 // SPDX-License-Identifier: GPL-2.0-or-later /* * Kernel Probes (KProbes) * kernel/kprobes.c * * Copyright (C) IBM Corporation, 2002, 2004 * * 2002-Oct Created by Vamsi Krishna S <vamsi_krishna@in.ibm.com> Kernel * Probes initial implementation (includes suggestions from * Rusty Russell). * 2004-Aug Updated by Prasanna S Panchamukhi <prasanna@in.ibm.com> with * hlists and exceptions notifier as suggested by Andi Kleen. * 2004-July Suparna Bhattacharya <suparna@in.ibm.com> added jumper probes * interface to access function arguments. * 2004-Sep Prasanna S Panchamukhi <prasanna@in.ibm.com> Changed Kprobes * exceptions notifier to be first on the priority list. * 2005-May Hien Nguyen <hien@us.ibm.com>, Jim Keniston * <jkenisto@us.ibm.com> and Prasanna S Panchamukhi * <prasanna@in.ibm.com> added function-return probes. */ #include <linux/kprobes.h> #include <linux/hash.h> #include <linux/init.h> #include <linux/slab.h> #include <linux/stddef.h> #include <linux/export.h> #include <linux/moduleloader.h> #include <linux/kallsyms.h> #include <linux/freezer.h> #include <linux/seq_file.h> #include <linux/debugfs.h> #include <linux/sysctl.h> #include <linux/kdebug.h> #include <linux/memory.h> #include <linux/ftrace.h> #include <linux/cpu.h> #include <linux/jump_label.h> #include <linux/perf_event.h> #include <linux/static_call.h> #include <asm/sections.h> #include <asm/cacheflush.h> #include <asm/errno.h> #include <linux/uaccess.h> #define KPROBE_HASH_BITS 6 #define KPROBE_TABLE_SIZE (1 << KPROBE_HASH_BITS) static int kprobes_initialized; /* kprobe_table can be accessed by * - Normal hlist traversal and RCU add/del under kprobe_mutex is held. * Or * - RCU hlist traversal under disabling preempt (breakpoint handlers) */ static struct hlist_head kprobe_table[KPROBE_TABLE_SIZE]; static struct hlist_head kretprobe_inst_table[KPROBE_TABLE_SIZE]; /* NOTE: change this value only with kprobe_mutex held */ static bool kprobes_all_disarmed; /* This protects kprobe_table and optimizing_list */ static DEFINE_MUTEX(kprobe_mutex); static DEFINE_PER_CPU(struct kprobe *, kprobe_instance) = NULL; static struct { raw_spinlock_t lock ____cacheline_aligned_in_smp; } kretprobe_table_locks[KPROBE_TABLE_SIZE]; kprobe_opcode_t * __weak kprobe_lookup_name(const char *name, unsigned int __unused) { return ((kprobe_opcode_t *)(kallsyms_lookup_name(name))); } static raw_spinlock_t *kretprobe_table_lock_ptr(unsigned long hash) { return &(kretprobe_table_locks[hash].lock); } /* Blacklist -- list of struct kprobe_blacklist_entry */ static LIST_HEAD(kprobe_blacklist); #ifdef __ARCH_WANT_KPROBES_INSN_SLOT /* * kprobe->ainsn.insn points to the copy of the instruction to be * single-stepped. x86_64, POWER4 and above have no-exec support and * stepping on the instruction on a vmalloced/kmalloced/data page * is a recipe for disaster */ struct kprobe_insn_page { struct list_head list; kprobe_opcode_t *insns; /* Page of instruction slots */ struct kprobe_insn_cache *cache; int nused; int ngarbage; char slot_used[]; }; #define KPROBE_INSN_PAGE_SIZE(slots) \ (offsetof(struct kprobe_insn_page, slot_used) + \ (sizeof(char) * (slots))) static int slots_per_page(struct kprobe_insn_cache *c) { return PAGE_SIZE/(c->insn_size * sizeof(kprobe_opcode_t)); } enum kprobe_slot_state { SLOT_CLEAN = 0, SLOT_DIRTY = 1, SLOT_USED = 2, }; void __weak *alloc_insn_page(void) { return module_alloc(PAGE_SIZE); } void __weak free_insn_page(void *page) { module_memfree(page); } struct kprobe_insn_cache kprobe_insn_slots = { .mutex = __MUTEX_INITIALIZER(kprobe_insn_slots.mutex), .alloc = alloc_insn_page, .free = free_insn_page, .sym = KPROBE_INSN_PAGE_SYM, .pages = LIST_HEAD_INIT(kprobe_insn_slots.pages), .insn_size = MAX_INSN_SIZE, .nr_garbage = 0, }; static int collect_garbage_slots(struct kprobe_insn_cache *c); /** * __get_insn_slot() - Find a slot on an executable page for an instruction. * We allocate an executable page if there's no room on existing ones. */ kprobe_opcode_t *__get_insn_slot(struct kprobe_insn_cache *c) { struct kprobe_insn_page *kip; kprobe_opcode_t *slot = NULL; /* Since the slot array is not protected by rcu, we need a mutex */ mutex_lock(&c->mutex); retry: rcu_read_lock(); list_for_each_entry_rcu(kip, &c->pages, list) { if (kip->nused < slots_per_page(c)) { int i; for (i = 0; i < slots_per_page(c); i++) { if (kip->slot_used[i] == SLOT_CLEAN) { kip->slot_used[i] = SLOT_USED; kip->nused++; slot = kip->insns + (i * c->insn_size); rcu_read_unlock(); goto out; } } /* kip->nused is broken. Fix it. */ kip->nused = slots_per_page(c); WARN_ON(1); } } rcu_read_unlock(); /* If there are any garbage slots, collect it and try again. */ if (c->nr_garbage && collect_garbage_slots(c) == 0) goto retry; /* All out of space. Need to allocate a new page. */ kip = kmalloc(KPROBE_INSN_PAGE_SIZE(slots_per_page(c)), GFP_KERNEL); if (!kip) goto out; /* * Use module_alloc so this page is within +/- 2GB of where the * kernel image and loaded module images reside. This is required * so x86_64 can correctly handle the %rip-relative fixups. */ kip->insns = c->alloc(); if (!kip->insns) { kfree(kip); goto out; } INIT_LIST_HEAD(&kip->list); memset(kip->slot_used, SLOT_CLEAN, slots_per_page(c)); kip->slot_used[0] = SLOT_USED; kip->nused = 1; kip->ngarbage = 0; kip->cache = c; list_add_rcu(&kip->list, &c->pages); slot = kip->insns; /* Record the perf ksymbol register event after adding the page */ perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_OOL, (unsigned long)kip->insns, PAGE_SIZE, false, c->sym); out: mutex_unlock(&c->mutex); return slot; } /* Return 1 if all garbages are collected, otherwise 0. */ static int collect_one_slot(struct kprobe_insn_page *kip, int idx) { kip->slot_used[idx] = SLOT_CLEAN; kip->nused--; if (kip->nused == 0) { /* * Page is no longer in use. Free it unless * it's the last one. We keep the last one * so as not to have to set it up again the * next time somebody inserts a probe. */ if (!list_is_singular(&kip->list)) { /* * Record perf ksymbol unregister event before removing * the page. */ perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_OOL, (unsigned long)kip->insns, PAGE_SIZE, true, kip->cache->sym); list_del_rcu(&kip->list); synchronize_rcu(); kip->cache->free(kip->insns); kfree(kip); } return 1; } return 0; } static int collect_garbage_slots(struct kprobe_insn_cache *c) { struct kprobe_insn_page *kip, *next; /* Ensure no-one is interrupted on the garbages */ synchronize_rcu(); list_for_each_entry_safe(kip, next, &c->pages, list) { int i; if (kip->ngarbage == 0) continue; kip->ngarbage = 0; /* we will collect all garbages */ for (i = 0; i < slots_per_page(c); i++) { if (kip->slot_used[i] == SLOT_DIRTY && collect_one_slot(kip, i)) break; } } c->nr_garbage = 0; return 0; } void __free_insn_slot(struct kprobe_insn_cache *c, kprobe_opcode_t *slot, int dirty) { struct kprobe_insn_page *kip; long idx; mutex_lock(&c->mutex); rcu_read_lock(); list_for_each_entry_rcu(kip, &c->pages, list) { idx = ((long)slot - (long)kip->insns) / (c->insn_size * sizeof(kprobe_opcode_t)); if (idx >= 0 && idx < slots_per_page(c)) goto out; } /* Could not find this slot. */ WARN_ON(1); kip = NULL; out: rcu_read_unlock(); /* Mark and sweep: this may sleep */ if (kip) { /* Check double free */ WARN_ON(kip->slot_used[idx] != SLOT_USED); if (dirty) { kip->slot_used[idx] = SLOT_DIRTY; kip->ngarbage++; if (++c->nr_garbage > slots_per_page(c)) collect_garbage_slots(c); } else { collect_one_slot(kip, idx); } } mutex_unlock(&c->mutex); } /* * Check given address is on the page of kprobe instruction slots. * This will be used for checking whether the address on a stack * is on a text area or not. */ bool __is_insn_slot_addr(struct kprobe_insn_cache *c, unsigned long addr) { struct kprobe_insn_page *kip; bool ret = false; rcu_read_lock(); list_for_each_entry_rcu(kip, &c->pages, list) { if (addr >= (unsigned long)kip->insns && addr < (unsigned long)kip->insns + PAGE_SIZE) { ret = true; break; } } rcu_read_unlock(); return ret; } int kprobe_cache_get_kallsym(struct kprobe_insn_cache *c, unsigned int *symnum, unsigned long *value, char *type, char *sym) { struct kprobe_insn_page *kip; int ret = -ERANGE; rcu_read_lock(); list_for_each_entry_rcu(kip, &c->pages, list) { if ((*symnum)--) continue; strlcpy(sym, c->sym, KSYM_NAME_LEN); *type = 't'; *value = (unsigned long)kip->insns; ret = 0; break; } rcu_read_unlock(); return ret; } #ifdef CONFIG_OPTPROBES /* For optimized_kprobe buffer */ struct kprobe_insn_cache kprobe_optinsn_slots = { .mutex = __MUTEX_INITIALIZER(kprobe_optinsn_slots.mutex), .alloc = alloc_insn_page, .free = free_insn_page, .sym = KPROBE_OPTINSN_PAGE_SYM, .pages = LIST_HEAD_INIT(kprobe_optinsn_slots.pages), /* .insn_size is initialized later */ .nr_garbage = 0, }; #endif #endif /* We have preemption disabled.. so it is safe to use __ versions */ static inline void set_kprobe_instance(struct kprobe *kp) { __this_cpu_write(kprobe_instance, kp); } static inline void reset_kprobe_instance(void) { __this_cpu_write(kprobe_instance, NULL); } /* * This routine is called either: * - under the kprobe_mutex - during kprobe_[un]register() * OR * - with preemption disabled - from arch/xxx/kernel/kprobes.c */ struct kprobe *get_kprobe(void *addr) { struct hlist_head *head; struct kprobe *p; head = &kprobe_table[hash_ptr(addr, KPROBE_HASH_BITS)]; hlist_for_each_entry_rcu(p, head, hlist, lockdep_is_held(&kprobe_mutex)) { if (p->addr == addr) return p; } return NULL; } NOKPROBE_SYMBOL(get_kprobe); static int aggr_pre_handler(struct kprobe *p, struct pt_regs *regs); /* Return true if the kprobe is an aggregator */ static inline int kprobe_aggrprobe(struct kprobe *p) { return p->pre_handler == aggr_pre_handler; } /* Return true(!0) if the kprobe is unused */ static inline int kprobe_unused(struct kprobe *p) { return kprobe_aggrprobe(p) && kprobe_disabled(p) && list_empty(&p->list); } /* * Keep all fields in the kprobe consistent */ static inline void copy_kprobe(struct kprobe *ap, struct kprobe *p) { memcpy(&p->opcode, &ap->opcode, sizeof(kprobe_opcode_t)); memcpy(&p->ainsn, &ap->ainsn, sizeof(struct arch_specific_insn)); } #ifdef CONFIG_OPTPROBES /* NOTE: change this value only with kprobe_mutex held */ static bool kprobes_allow_optimization; /* * Call all pre_handler on the list, but ignores its return value. * This must be called from arch-dep optimized caller. */ void opt_pre_handler(struct kprobe *p, struct pt_regs *regs) { struct kprobe *kp; list_for_each_entry_rcu(kp, &p->list, list) { if (kp->pre_handler && likely(!kprobe_disabled(kp))) { set_kprobe_instance(kp); kp->pre_handler(kp, regs); } reset_kprobe_instance(); } } NOKPROBE_SYMBOL(opt_pre_handler); /* Free optimized instructions and optimized_kprobe */ static void free_aggr_kprobe(struct kprobe *p) { struct optimized_kprobe *op; op = container_of(p, struct optimized_kprobe, kp); arch_remove_optimized_kprobe(op); arch_remove_kprobe(p); kfree(op); } /* Return true(!0) if the kprobe is ready for optimization. */ static inline int kprobe_optready(struct kprobe *p) { struct optimized_kprobe *op; if (kprobe_aggrprobe(p)) { op = container_of(p, struct optimized_kprobe, kp); return arch_prepared_optinsn(&op->optinsn); } return 0; } /* Return true(!0) if the kprobe is disarmed. Note: p must be on hash list */ static inline int kprobe_disarmed(struct kprobe *p) { struct optimized_kprobe *op; /* If kprobe is not aggr/opt probe, just return kprobe is disabled */ if (!kprobe_aggrprobe(p)) return kprobe_disabled(p); op = container_of(p, struct optimized_kprobe, kp); return kprobe_disabled(p) && list_empty(&op->list); } /* Return true(!0) if the probe is queued on (un)optimizing lists */ static int kprobe_queued(struct kprobe *p) { struct optimized_kprobe *op; if (kprobe_aggrprobe(p)) { op = container_of(p, struct optimized_kprobe, kp); if (!list_empty(&op->list)) return 1; } return 0; } /* * Return an optimized kprobe whose optimizing code replaces * instructions including addr (exclude breakpoint). */ static struct kprobe *get_optimized_kprobe(unsigned long addr) { int i; struct kprobe *p = NULL; struct optimized_kprobe *op; /* Don't check i == 0, since that is a breakpoint case. */ for (i = 1; !p && i < MAX_OPTIMIZED_LENGTH; i++) p = get_kprobe((void *)(addr - i)); if (p && kprobe_optready(p)) { op = container_of(p, struct optimized_kprobe, kp); if (arch_within_optimized_kprobe(op, addr)) return p; } return NULL; } /* Optimization staging list, protected by kprobe_mutex */ static LIST_HEAD(optimizing_list); static LIST_HEAD(unoptimizing_list); static LIST_HEAD(freeing_list); static void kprobe_optimizer(struct work_struct *work); static DECLARE_DELAYED_WORK(optimizing_work, kprobe_optimizer); #define OPTIMIZE_DELAY 5 /* * Optimize (replace a breakpoint with a jump) kprobes listed on * optimizing_list. */ static void do_optimize_kprobes(void) { lockdep_assert_held(&text_mutex); /* * The optimization/unoptimization refers online_cpus via * stop_machine() and cpu-hotplug modifies online_cpus. * And same time, text_mutex will be held in cpu-hotplug and here. * This combination can cause a deadlock (cpu-hotplug try to lock * text_mutex but stop_machine can not be done because online_cpus * has been changed) * To avoid this deadlock, caller must have locked cpu hotplug * for preventing cpu-hotplug outside of text_mutex locking. */ lockdep_assert_cpus_held(); /* Optimization never be done when disarmed */ if (kprobes_all_disarmed || !kprobes_allow_optimization || list_empty(&optimizing_list)) return; arch_optimize_kprobes(&optimizing_list); } /* * Unoptimize (replace a jump with a breakpoint and remove the breakpoint * if need) kprobes listed on unoptimizing_list. */ static void do_unoptimize_kprobes(void) { struct optimized_kprobe *op, *tmp; lockdep_assert_held(&text_mutex); /* See comment in do_optimize_kprobes() */ lockdep_assert_cpus_held(); /* Unoptimization must be done anytime */ if (list_empty(&unoptimizing_list)) return; arch_unoptimize_kprobes(&unoptimizing_list, &freeing_list); /* Loop free_list for disarming */ list_for_each_entry_safe(op, tmp, &freeing_list, list) { /* Switching from detour code to origin */ op->kp.flags &= ~KPROBE_FLAG_OPTIMIZED; /* Disarm probes if marked disabled */ if (kprobe_disabled(&op->kp)) arch_disarm_kprobe(&op->kp); if (kprobe_unused(&op->kp)) { /* * Remove unused probes from hash list. After waiting * for synchronization, these probes are reclaimed. * (reclaiming is done by do_free_cleaned_kprobes.) */ hlist_del_rcu(&op->kp.hlist); } else list_del_init(&op->list); } } /* Reclaim all kprobes on the free_list */ static void do_free_cleaned_kprobes(void) { struct optimized_kprobe *op, *tmp; list_for_each_entry_safe(op, tmp, &freeing_list, list) { list_del_init(&op->list); if (WARN_ON_ONCE(!kprobe_unused(&op->kp))) { /* * This must not happen, but if there is a kprobe * still in use, keep it on kprobes hash list. */ continue; } free_aggr_kprobe(&op->kp); } } /* Start optimizer after OPTIMIZE_DELAY passed */ static void kick_kprobe_optimizer(void) { schedule_delayed_work(&optimizing_work, OPTIMIZE_DELAY); } /* Kprobe jump optimizer */ static void kprobe_optimizer(struct work_struct *work) { mutex_lock(&kprobe_mutex); cpus_read_lock(); mutex_lock(&text_mutex); /* * Step 1: Unoptimize kprobes and collect cleaned (unused and disarmed) * kprobes before waiting for quiesence period. */ do_unoptimize_kprobes(); /* * Step 2: Wait for quiesence period to ensure all potentially * preempted tasks to have normally scheduled. Because optprobe * may modify multiple instructions, there is a chance that Nth * instruction is preempted. In that case, such tasks can return * to 2nd-Nth byte of jump instruction. This wait is for avoiding it. * Note that on non-preemptive kernel, this is transparently converted * to synchronoze_sched() to wait for all interrupts to have completed. */ synchronize_rcu_tasks(); /* Step 3: Optimize kprobes after quiesence period */ do_optimize_kprobes(); /* Step 4: Free cleaned kprobes after quiesence period */ do_free_cleaned_kprobes(); mutex_unlock(&text_mutex); cpus_read_unlock(); /* Step 5: Kick optimizer again if needed */ if (!list_empty(&optimizing_list) || !list_empty(&unoptimizing_list)) kick_kprobe_optimizer(); mutex_unlock(&kprobe_mutex); } /* Wait for completing optimization and unoptimization */ void wait_for_kprobe_optimizer(void) { mutex_lock(&kprobe_mutex); while (!list_empty(&optimizing_list) || !list_empty(&unoptimizing_list)) { mutex_unlock(&kprobe_mutex); /* this will also make optimizing_work execute immmediately */ flush_delayed_work(&optimizing_work); /* @optimizing_work might not have been queued yet, relax */ cpu_relax(); mutex_lock(&kprobe_mutex); } mutex_unlock(&kprobe_mutex); } static bool optprobe_queued_unopt(struct optimized_kprobe *op) { struct optimized_kprobe *_op; list_for_each_entry(_op, &unoptimizing_list, list) { if (op == _op) return true; } return false; } /* Optimize kprobe if p is ready to be optimized */ static void optimize_kprobe(struct kprobe *p) { struct optimized_kprobe *op; /* Check if the kprobe is disabled or not ready for optimization. */ if (!kprobe_optready(p) || !kprobes_allow_optimization || (kprobe_disabled(p) || kprobes_all_disarmed)) return; /* kprobes with post_handler can not be optimized */ if (p->post_handler) return; op = container_of(p, struct optimized_kprobe, kp); /* Check there is no other kprobes at the optimized instructions */ if (arch_check_optimized_kprobe(op) < 0) return; /* Check if it is already optimized. */ if (op->kp.flags & KPROBE_FLAG_OPTIMIZED) { if (optprobe_queued_unopt(op)) { /* This is under unoptimizing. Just dequeue the probe */ list_del_init(&op->list); } return; } op->kp.flags |= KPROBE_FLAG_OPTIMIZED; /* On unoptimizing/optimizing_list, op must have OPTIMIZED flag */ if (WARN_ON_ONCE(!list_empty(&op->list))) return; list_add(&op->list, &optimizing_list); kick_kprobe_optimizer(); } /* Short cut to direct unoptimizing */ static void force_unoptimize_kprobe(struct optimized_kprobe *op) { lockdep_assert_cpus_held(); arch_unoptimize_kprobe(op); op->kp.flags &= ~KPROBE_FLAG_OPTIMIZED; } /* Unoptimize a kprobe if p is optimized */ static void unoptimize_kprobe(struct kprobe *p, bool force) { struct optimized_kprobe *op; if (!kprobe_aggrprobe(p) || kprobe_disarmed(p)) return; /* This is not an optprobe nor optimized */ op = container_of(p, struct optimized_kprobe, kp); if (!kprobe_optimized(p)) return; if (!list_empty(&op->list)) { if (optprobe_queued_unopt(op)) { /* Queued in unoptimizing queue */ if (force) { /* * Forcibly unoptimize the kprobe here, and queue it * in the freeing list for release afterwards. */ force_unoptimize_kprobe(op); list_move(&op->list, &freeing_list); } } else { /* Dequeue from the optimizing queue */ list_del_init(&op->list); op->kp.flags &= ~KPROBE_FLAG_OPTIMIZED; } return; } /* Optimized kprobe case */ if (force) { /* Forcibly update the code: this is a special case */ force_unoptimize_kprobe(op); } else { list_add(&op->list, &unoptimizing_list); kick_kprobe_optimizer(); } } /* Cancel unoptimizing for reusing */ static int reuse_unused_kprobe(struct kprobe *ap) { struct optimized_kprobe *op; /* * Unused kprobe MUST be on the way of delayed unoptimizing (means * there is still a relative jump) and disabled. */ op = container_of(ap, struct optimized_kprobe, kp); WARN_ON_ONCE(list_empty(&op->list)); /* Enable the probe again */ ap->flags &= ~KPROBE_FLAG_DISABLED; /* Optimize it again (remove from op->list) */ if (!kprobe_optready(ap)) return -EINVAL; optimize_kprobe(ap); return 0; } /* Remove optimized instructions */ static void kill_optimized_kprobe(struct kprobe *p) { struct optimized_kprobe *op; op = container_of(p, struct optimized_kprobe, kp); if (!list_empty(&op->list)) /* Dequeue from the (un)optimization queue */ list_del_init(&op->list); op->kp.flags &= ~KPROBE_FLAG_OPTIMIZED; if (kprobe_unused(p)) { /* Enqueue if it is unused */ list_add(&op->list, &freeing_list); /* * Remove unused probes from the hash list. After waiting * for synchronization, this probe is reclaimed. * (reclaiming is done by do_free_cleaned_kprobes().) */ hlist_del_rcu(&op->kp.hlist); } /* Don't touch the code, because it is already freed. */ arch_remove_optimized_kprobe(op); } static inline void __prepare_optimized_kprobe(struct optimized_kprobe *op, struct kprobe *p) { if (!kprobe_ftrace(p)) arch_prepare_optimized_kprobe(op, p); } /* Try to prepare optimized instructions */ static void prepare_optimized_kprobe(struct kprobe *p) { struct optimized_kprobe *op; op = container_of(p, struct optimized_kprobe, kp); __prepare_optimized_kprobe(op, p); } /* Allocate new optimized_kprobe and try to prepare optimized instructions */ static struct kprobe *alloc_aggr_kprobe(struct kprobe *p) { struct optimized_kprobe *op; op = kzalloc(sizeof(struct optimized_kprobe), GFP_KERNEL); if (!op) return NULL; INIT_LIST_HEAD(&op->list); op->kp.addr = p->addr; __prepare_optimized_kprobe(op, p); return &op->kp; } static void init_aggr_kprobe(struct kprobe *ap, struct kprobe *p); /* * Prepare an optimized_kprobe and optimize it * NOTE: p must be a normal registered kprobe */ static void try_to_optimize_kprobe(struct kprobe *p) { struct kprobe *ap; struct optimized_kprobe *op; /* Impossible to optimize ftrace-based kprobe */ if (kprobe_ftrace(p)) return; /* For preparing optimization, jump_label_text_reserved() is called */ cpus_read_lock(); jump_label_lock(); mutex_lock(&text_mutex); ap = alloc_aggr_kprobe(p); if (!ap) goto out; op = container_of(ap, struct optimized_kprobe, kp); if (!arch_prepared_optinsn(&op->optinsn)) { /* If failed to setup optimizing, fallback to kprobe */ arch_remove_optimized_kprobe(op); kfree(op); goto out; } init_aggr_kprobe(ap, p); optimize_kprobe(ap); /* This just kicks optimizer thread */ out: mutex_unlock(&text_mutex); jump_label_unlock(); cpus_read_unlock(); } static void optimize_all_kprobes(void) { struct hlist_head *head; struct kprobe *p; unsigned int i; mutex_lock(&kprobe_mutex); /* If optimization is already allowed, just return */ if (kprobes_allow_optimization) goto out; cpus_read_lock(); kprobes_allow_optimization = true; for (i = 0; i < KPROBE_TABLE_SIZE; i++) { head = &kprobe_table[i]; hlist_for_each_entry(p, head, hlist) if (!kprobe_disabled(p)) optimize_kprobe(p); } cpus_read_unlock(); printk(KERN_INFO "Kprobes globally optimized\n"); out: mutex_unlock(&kprobe_mutex); } #ifdef CONFIG_SYSCTL static void unoptimize_all_kprobes(void) { struct hlist_head *head; struct kprobe *p; unsigned int i; mutex_lock(&kprobe_mutex); /* If optimization is already prohibited, just return */ if (!kprobes_allow_optimization) { mutex_unlock(&kprobe_mutex); return; } cpus_read_lock(); kprobes_allow_optimization = false; for (i = 0; i < KPROBE_TABLE_SIZE; i++) { head = &kprobe_table[i]; hlist_for_each_entry(p, head, hlist) { if (!kprobe_disabled(p)) unoptimize_kprobe(p, false); } } cpus_read_unlock(); mutex_unlock(&kprobe_mutex); /* Wait for unoptimizing completion */ wait_for_kprobe_optimizer(); printk(KERN_INFO "Kprobes globally unoptimized\n"); } static DEFINE_MUTEX(kprobe_sysctl_mutex); int sysctl_kprobes_optimization; int proc_kprobes_optimization_handler(struct ctl_table *table, int write, void *buffer, size_t *length, loff_t *ppos) { int ret; mutex_lock(&kprobe_sysctl_mutex); sysctl_kprobes_optimization = kprobes_allow_optimization ? 1 : 0; ret = proc_dointvec_minmax(table, write, buffer, length, ppos); if (sysctl_kprobes_optimization) optimize_all_kprobes(); else unoptimize_all_kprobes(); mutex_unlock(&kprobe_sysctl_mutex); return ret; } #endif /* CONFIG_SYSCTL */ /* Put a breakpoint for a probe. Must be called with text_mutex locked */ static void __arm_kprobe(struct kprobe *p) { struct kprobe *_p; /* Check collision with other optimized kprobes */ _p = get_optimized_kprobe((unsigned long)p->addr); if (unlikely(_p)) /* Fallback to unoptimized kprobe */ unoptimize_kprobe(_p, true); arch_arm_kprobe(p); optimize_kprobe(p); /* Try to optimize (add kprobe to a list) */ } /* Remove the breakpoint of a probe. Must be called with text_mutex locked */ static void __disarm_kprobe(struct kprobe *p, bool reopt) { struct kprobe *_p; /* Try to unoptimize */ unoptimize_kprobe(p, kprobes_all_disarmed); if (!kprobe_queued(p)) { arch_disarm_kprobe(p); /* If another kprobe was blocked, optimize it. */ _p = get_optimized_kprobe((unsigned long)p->addr); if (unlikely(_p) && reopt) optimize_kprobe(_p); } /* TODO: reoptimize others after unoptimized this probe */ } #else /* !CONFIG_OPTPROBES */ #define optimize_kprobe(p) do {} while (0) #define unoptimize_kprobe(p, f) do {} while (0) #define kill_optimized_kprobe(p) do {} while (0) #define prepare_optimized_kprobe(p) do {} while (0) #define try_to_optimize_kprobe(p) do {} while (0) #define __arm_kprobe(p) arch_arm_kprobe(p) #define __disarm_kprobe(p, o) arch_disarm_kprobe(p) #define kprobe_disarmed(p) kprobe_disabled(p) #define wait_for_kprobe_optimizer() do {} while (0) static int reuse_unused_kprobe(struct kprobe *ap) { /* * If the optimized kprobe is NOT supported, the aggr kprobe is * released at the same time that the last aggregated kprobe is * unregistered. * Thus there should be no chance to reuse unused kprobe. */ printk(KERN_ERR "Error: There should be no unused kprobe here.\n"); return -EINVAL; } static void free_aggr_kprobe(struct kprobe *p) { arch_remove_kprobe(p); kfree(p); } static struct kprobe *alloc_aggr_kprobe(struct kprobe *p) { return kzalloc(sizeof(struct kprobe), GFP_KERNEL); } #endif /* CONFIG_OPTPROBES */ #ifdef CONFIG_KPROBES_ON_FTRACE static struct ftrace_ops kprobe_ftrace_ops __read_mostly = { .func = kprobe_ftrace_handler, .flags = FTRACE_OPS_FL_SAVE_REGS, }; static struct ftrace_ops kprobe_ipmodify_ops __read_mostly = { .func = kprobe_ftrace_handler, .flags = FTRACE_OPS_FL_SAVE_REGS | FTRACE_OPS_FL_IPMODIFY, }; static int kprobe_ipmodify_enabled; static int kprobe_ftrace_enabled; /* Must ensure p->addr is really on ftrace */ static int prepare_kprobe(struct kprobe *p) { if (!kprobe_ftrace(p)) return arch_prepare_kprobe(p); return arch_prepare_kprobe_ftrace(p); } /* Caller must lock kprobe_mutex */ static int __arm_kprobe_ftrace(struct kprobe *p, struct ftrace_ops *ops, int *cnt) { int ret = 0; ret = ftrace_set_filter_ip(ops, (unsigned long)p->addr, 0, 0); if (ret) { pr_debug("Failed to arm kprobe-ftrace at %pS (%d)\n", p->addr, ret); return ret; } if (*cnt == 0) { ret = register_ftrace_function(ops); if (ret) { pr_debug("Failed to init kprobe-ftrace (%d)\n", ret); goto err_ftrace; } } (*cnt)++; return ret; err_ftrace: /* * At this point, sinec ops is not registered, we should be sefe from * registering empty filter. */ ftrace_set_filter_ip(ops, (unsigned long)p->addr, 1, 0); return ret; } static int arm_kprobe_ftrace(struct kprobe *p) { bool ipmodify = (p->post_handler != NULL); return __arm_kprobe_ftrace(p, ipmodify ? &kprobe_ipmodify_ops : &kprobe_ftrace_ops, ipmodify ? &kprobe_ipmodify_enabled : &kprobe_ftrace_enabled); } /* Caller must lock kprobe_mutex */ static int __disarm_kprobe_ftrace(struct kprobe *p, struct ftrace_ops *ops, int *cnt) { int ret = 0; if (*cnt == 1) { ret = unregister_ftrace_function(ops); if (WARN(ret < 0, "Failed to unregister kprobe-ftrace (%d)\n", ret)) return ret; } (*cnt)--; ret = ftrace_set_filter_ip(ops, (unsigned long)p->addr, 1, 0); WARN_ONCE(ret < 0, "Failed to disarm kprobe-ftrace at %pS (%d)\n", p->addr, ret); return ret; } static int disarm_kprobe_ftrace(struct kprobe *p) { bool ipmodify = (p->post_handler != NULL); return __disarm_kprobe_ftrace(p, ipmodify ? &kprobe_ipmodify_ops : &kprobe_ftrace_ops, ipmodify ? &kprobe_ipmodify_enabled : &kprobe_ftrace_enabled); } #else /* !CONFIG_KPROBES_ON_FTRACE */ static inline int prepare_kprobe(struct kprobe *p) { return arch_prepare_kprobe(p); } static inline int arm_kprobe_ftrace(struct kprobe *p) { return -ENODEV; } static inline int disarm_kprobe_ftrace(struct kprobe *p) { return -ENODEV; } #endif /* Arm a kprobe with text_mutex */ static int arm_kprobe(struct kprobe *kp) { if (unlikely(kprobe_ftrace(kp))) return arm_kprobe_ftrace(kp); cpus_read_lock(); mutex_lock(&text_mutex); __arm_kprobe(kp); mutex_unlock(&text_mutex); cpus_read_unlock(); return 0; } /* Disarm a kprobe with text_mutex */ static int disarm_kprobe(struct kprobe *kp, bool reopt) { if (unlikely(kprobe_ftrace(kp))) return disarm_kprobe_ftrace(kp); cpus_read_lock(); mutex_lock(&text_mutex); __disarm_kprobe(kp, reopt); mutex_unlock(&text_mutex); cpus_read_unlock(); return 0; } /* * Aggregate handlers for multiple kprobes support - these handlers * take care of invoking the individual kprobe handlers on p->list */ static int aggr_pre_handler(struct kprobe *p, struct pt_regs *regs) { struct kprobe *kp; list_for_each_entry_rcu(kp, &p->list, list) { if (kp->pre_handler && likely(!kprobe_disabled(kp))) { set_kprobe_instance(kp); if (kp->pre_handler(kp, regs)) return 1; } reset_kprobe_instance(); } return 0; } NOKPROBE_SYMBOL(aggr_pre_handler); static void aggr_post_handler(struct kprobe *p, struct pt_regs *regs, unsigned long flags) { struct kprobe *kp; list_for_each_entry_rcu(kp, &p->list, list) { if (kp->post_handler && likely(!kprobe_disabled(kp))) { set_kprobe_instance(kp); kp->post_handler(kp, regs, flags); reset_kprobe_instance(); } } } NOKPROBE_SYMBOL(aggr_post_handler); static int aggr_fault_handler(struct kprobe *p, struct pt_regs *regs, int trapnr) { struct kprobe *cur = __this_cpu_read(kprobe_instance); /* * if we faulted "during" the execution of a user specified * probe handler, invoke just that probe's fault handler */ if (cur && cur->fault_handler) { if (cur->fault_handler(cur, regs, trapnr)) return 1; } return 0; } NOKPROBE_SYMBOL(aggr_fault_handler); /* Walks the list and increments nmissed count for multiprobe case */ void kprobes_inc_nmissed_count(struct kprobe *p) { struct kprobe *kp; if (!kprobe_aggrprobe(p)) { p->nmissed++; } else { list_for_each_entry_rcu(kp, &p->list, list) kp->nmissed++; } return; } NOKPROBE_SYMBOL(kprobes_inc_nmissed_count); static void recycle_rp_inst(struct kretprobe_instance *ri) { struct kretprobe *rp = ri->rp; /* remove rp inst off the rprobe_inst_table */ hlist_del(&ri->hlist); INIT_HLIST_NODE(&ri->hlist); if (likely(rp)) { raw_spin_lock(&rp->lock); hlist_add_head(&ri->hlist, &rp->free_instances); raw_spin_unlock(&rp->lock); } else kfree_rcu(ri, rcu); } NOKPROBE_SYMBOL(recycle_rp_inst); static void kretprobe_hash_lock(struct task_struct *tsk, struct hlist_head **head, unsigned long *flags) __acquires(hlist_lock) { unsigned long hash = hash_ptr(tsk, KPROBE_HASH_BITS); raw_spinlock_t *hlist_lock; *head = &kretprobe_inst_table[hash]; hlist_lock = kretprobe_table_lock_ptr(hash); /* * Nested is a workaround that will soon not be needed. * There's other protections that make sure the same lock * is not taken on the same CPU that lockdep is unaware of. * Differentiate when it is taken in NMI context. */ raw_spin_lock_irqsave_nested(hlist_lock, *flags, !!in_nmi()); } NOKPROBE_SYMBOL(kretprobe_hash_lock); static void kretprobe_table_lock(unsigned long hash, unsigned long *flags) __acquires(hlist_lock) { raw_spinlock_t *hlist_lock = kretprobe_table_lock_ptr(hash); /* * Nested is a workaround that will soon not be needed. * There's other protections that make sure the same lock * is not taken on the same CPU that lockdep is unaware of. * Differentiate when it is taken in NMI context. */ raw_spin_lock_irqsave_nested(hlist_lock, *flags, !!in_nmi()); } NOKPROBE_SYMBOL(kretprobe_table_lock); static void kretprobe_hash_unlock(struct task_struct *tsk, unsigned long *flags) __releases(hlist_lock) { unsigned long hash = hash_ptr(tsk, KPROBE_HASH_BITS); raw_spinlock_t *hlist_lock; hlist_lock = kretprobe_table_lock_ptr(hash); raw_spin_unlock_irqrestore(hlist_lock, *flags); } NOKPROBE_SYMBOL(kretprobe_hash_unlock); static void kretprobe_table_unlock(unsigned long hash, unsigned long *flags) __releases(hlist_lock) { raw_spinlock_t *hlist_lock = kretprobe_table_lock_ptr(hash); raw_spin_unlock_irqrestore(hlist_lock, *flags); } NOKPROBE_SYMBOL(kretprobe_table_unlock); static struct kprobe kprobe_busy = { .addr = (void *) get_kprobe, }; void kprobe_busy_begin(void) { struct kprobe_ctlblk *kcb; preempt_disable(); __this_cpu_write(current_kprobe, &kprobe_busy); kcb = get_kprobe_ctlblk(); kcb->kprobe_status = KPROBE_HIT_ACTIVE; } void kprobe_busy_end(void) { __this_cpu_write(current_kprobe, NULL); preempt_enable(); } /* * This function is called from finish_task_switch when task tk becomes dead, * so that we can recycle any function-return probe instances associated * with this task. These left over instances represent probed functions * that have been called but will never return. */ void kprobe_flush_task(struct task_struct *tk) { struct kretprobe_instance *ri; struct hlist_head *head; struct hlist_node *tmp; unsigned long hash, flags = 0; if (unlikely(!kprobes_initialized)) /* Early boot. kretprobe_table_locks not yet initialized. */ return; kprobe_busy_begin(); hash = hash_ptr(tk, KPROBE_HASH_BITS); head = &kretprobe_inst_table[hash]; kretprobe_table_lock(hash, &flags); hlist_for_each_entry_safe(ri, tmp, head, hlist) { if (ri->task == tk) recycle_rp_inst(ri); } kretprobe_table_unlock(hash, &flags); kprobe_busy_end(); } NOKPROBE_SYMBOL(kprobe_flush_task); static inline void free_rp_inst(struct kretprobe *rp) { struct kretprobe_instance *ri; struct hlist_node *next; hlist_for_each_entry_safe(ri, next, &rp->free_instances, hlist) { hlist_del(&ri->hlist); kfree(ri); } } static void cleanup_rp_inst(struct kretprobe *rp) { unsigned long flags, hash; struct kretprobe_instance *ri; struct hlist_node *next; struct hlist_head *head; /* To avoid recursive kretprobe by NMI, set kprobe busy here */ kprobe_busy_begin(); for (hash = 0; hash < KPROBE_TABLE_SIZE; hash++) { kretprobe_table_lock(hash, &flags); head = &kretprobe_inst_table[hash]; hlist_for_each_entry_safe(ri, next, head, hlist) { if (ri->rp == rp) ri->rp = NULL; } kretprobe_table_unlock(hash, &flags); } kprobe_busy_end(); free_rp_inst(rp); } NOKPROBE_SYMBOL(cleanup_rp_inst); /* Add the new probe to ap->list */ static int add_new_kprobe(struct kprobe *ap, struct kprobe *p) { if (p->post_handler) unoptimize_kprobe(ap, true); /* Fall back to normal kprobe */ list_add_rcu(&p->list, &ap->list); if (p->post_handler && !ap->post_handler) ap->post_handler = aggr_post_handler; return 0; } /* * Fill in the required fields of the "manager kprobe". Replace the * earlier kprobe in the hlist with the manager kprobe */ static void init_aggr_kprobe(struct kprobe *ap, struct kprobe *p) { /* Copy p's insn slot to ap */ copy_kprobe(p, ap); flush_insn_slot(ap); ap->addr = p->addr; ap->flags = p->flags & ~KPROBE_FLAG_OPTIMIZED; ap->pre_handler = aggr_pre_handler; ap->fault_handler = aggr_fault_handler; /* We don't care the kprobe which has gone. */ if (p->post_handler && !kprobe_gone(p)) ap->post_handler = aggr_post_handler; INIT_LIST_HEAD(&ap->list); INIT_HLIST_NODE(&ap->hlist); list_add_rcu(&p->list, &ap->list); hlist_replace_rcu(&p->hlist, &ap->hlist); } /* * This is the second or subsequent kprobe at the address - handle * the intricacies */ static int register_aggr_kprobe(struct kprobe *orig_p, struct kprobe *p) { int ret = 0; struct kprobe *ap = orig_p; cpus_read_lock(); /* For preparing optimization, jump_label_text_reserved() is called */ jump_label_lock(); mutex_lock(&text_mutex); if (!kprobe_aggrprobe(orig_p)) { /* If orig_p is not an aggr_kprobe, create new aggr_kprobe. */ ap = alloc_aggr_kprobe(orig_p); if (!ap) { ret = -ENOMEM; goto out; } init_aggr_kprobe(ap, orig_p); } else if (kprobe_unused(ap)) { /* This probe is going to die. Rescue it */ ret = reuse_unused_kprobe(ap); if (ret) goto out; } if (kprobe_gone(ap)) { /* * Attempting to insert new probe at the same location that * had a probe in the module vaddr area which already * freed. So, the instruction slot has already been * released. We need a new slot for the new probe. */ ret = arch_prepare_kprobe(ap); if (ret) /* * Even if fail to allocate new slot, don't need to * free aggr_probe. It will be used next time, or * freed by unregister_kprobe. */ goto out; /* Prepare optimized instructions if possible. */ prepare_optimized_kprobe(ap); /* * Clear gone flag to prevent allocating new slot again, and * set disabled flag because it is not armed yet. */ ap->flags = (ap->flags & ~KPROBE_FLAG_GONE) | KPROBE_FLAG_DISABLED; } /* Copy ap's insn slot to p */ copy_kprobe(ap, p); ret = add_new_kprobe(ap, p); out: mutex_unlock(&text_mutex); jump_label_unlock(); cpus_read_unlock(); if (ret == 0 && kprobe_disabled(ap) && !kprobe_disabled(p)) { ap->flags &= ~KPROBE_FLAG_DISABLED; if (!kprobes_all_disarmed) { /* Arm the breakpoint again. */ ret = arm_kprobe(ap); if (ret) { ap->flags |= KPROBE_FLAG_DISABLED; list_del_rcu(&p->list); synchronize_rcu(); } } } return ret; } bool __weak arch_within_kprobe_blacklist(unsigned long addr) { /* The __kprobes marked functions and entry code must not be probed */ return addr >= (unsigned long)__kprobes_text_start && addr < (unsigned long)__kprobes_text_end; } static bool __within_kprobe_blacklist(unsigned long addr) { struct kprobe_blacklist_entry *ent; if (arch_within_kprobe_blacklist(addr)) return true; /* * If there exists a kprobe_blacklist, verify and * fail any probe registration in the prohibited area */ list_for_each_entry(ent, &kprobe_blacklist, list) { if (addr >= ent->start_addr && addr < ent->end_addr) return true; } return false; } bool within_kprobe_blacklist(unsigned long addr) { char symname[KSYM_NAME_LEN], *p; if (__within_kprobe_blacklist(addr)) return true; /* Check if the address is on a suffixed-symbol */ if (!lookup_symbol_name(addr, symname)) { p = strchr(symname, '.'); if (!p) return false; *p = '\0'; addr = (unsigned long)kprobe_lookup_name(symname, 0); if (addr) return __within_kprobe_blacklist(addr); } return false; } /* * If we have a symbol_name argument, look it up and add the offset field * to it. This way, we can specify a relative address to a symbol. * This returns encoded errors if it fails to look up symbol or invalid * combination of parameters. */ static kprobe_opcode_t *_kprobe_addr(kprobe_opcode_t *addr, const char *symbol_name, unsigned int offset) { if ((symbol_name && addr) || (!symbol_name && !addr)) goto invalid; if (symbol_name) { addr = kprobe_lookup_name(symbol_name, offset); if (!addr) return ERR_PTR(-ENOENT); } addr = (kprobe_opcode_t *)(((char *)addr) + offset); if (addr) return addr; invalid: return ERR_PTR(-EINVAL); } static kprobe_opcode_t *kprobe_addr(struct kprobe *p) { return _kprobe_addr(p->addr, p->symbol_name, p->offset); } /* Check passed kprobe is valid and return kprobe in kprobe_table. */ static struct kprobe *__get_valid_kprobe(struct kprobe *p) { struct kprobe *ap, *list_p; lockdep_assert_held(&kprobe_mutex); ap = get_kprobe(p->addr); if (unlikely(!ap)) return NULL; if (p != ap) { list_for_each_entry(list_p, &ap->list, list) if (list_p == p) /* kprobe p is a valid probe */ goto valid; return NULL; } valid: return ap; } /* Return error if the kprobe is being re-registered */ static inline int check_kprobe_rereg(struct kprobe *p) { int ret = 0; mutex_lock(&kprobe_mutex); if (__get_valid_kprobe(p)) ret = -EINVAL; mutex_unlock(&kprobe_mutex); return ret; } int __weak arch_check_ftrace_location(struct kprobe *p) { unsigned long ftrace_addr; ftrace_addr = ftrace_location((unsigned long)p->addr); if (ftrace_addr) { #ifdef CONFIG_KPROBES_ON_FTRACE /* Given address is not on the instruction boundary */ if ((unsigned long)p->addr != ftrace_addr) return -EILSEQ; p->flags |= KPROBE_FLAG_FTRACE; #else /* !CONFIG_KPROBES_ON_FTRACE */ return -EINVAL; #endif } return 0; } static int check_kprobe_address_safe(struct kprobe *p, struct module **probed_mod) { int ret; ret = arch_check_ftrace_location(p); if (ret) return ret; jump_label_lock(); preempt_disable(); /* Ensure it is not in reserved area nor out of text */ if (!kernel_text_address((unsigned long) p->addr) || within_kprobe_blacklist((unsigned long) p->addr) || jump_label_text_reserved(p->addr, p->addr) || static_call_text_reserved(p->addr, p->addr) || find_bug((unsigned long)p->addr)) { ret = -EINVAL; goto out; } /* Check if are we probing a module */ *probed_mod = __module_text_address((unsigned long) p->addr); if (*probed_mod) { /* * We must hold a refcount of the probed module while updating * its code to prohibit unexpected unloading. */ if (unlikely(!try_module_get(*probed_mod))) { ret = -ENOENT; goto out; } /* * If the module freed .init.text, we couldn't insert * kprobes in there. */ if (within_module_init((unsigned long)p->addr, *probed_mod) && (*probed_mod)->state != MODULE_STATE_COMING) { module_put(*probed_mod); *probed_mod = NULL; ret = -ENOENT; } } out: preempt_enable(); jump_label_unlock(); return ret; } int register_kprobe(struct kprobe *p) { int ret; struct kprobe *old_p; struct module *probed_mod; kprobe_opcode_t *addr; /* Adjust probe address from symbol */ addr = kprobe_addr(p); if (IS_ERR(addr)) return PTR_ERR(addr); p->addr = addr; ret = check_kprobe_rereg(p); if (ret) return ret; /* User can pass only KPROBE_FLAG_DISABLED to register_kprobe */ p->flags &= KPROBE_FLAG_DISABLED; p->nmissed = 0; INIT_LIST_HEAD(&p->list); ret = check_kprobe_address_safe(p, &probed_mod); if (ret) return ret; mutex_lock(&kprobe_mutex); old_p = get_kprobe(p->addr); if (old_p) { /* Since this may unoptimize old_p, locking text_mutex. */ ret = register_aggr_kprobe(old_p, p); goto out; } cpus_read_lock(); /* Prevent text modification */ mutex_lock(&text_mutex); ret = prepare_kprobe(p); mutex_unlock(&text_mutex); cpus_read_unlock(); if (ret) goto out; INIT_HLIST_NODE(&p->hlist); hlist_add_head_rcu(&p->hlist, &kprobe_table[hash_ptr(p->addr, KPROBE_HASH_BITS)]); if (!kprobes_all_disarmed && !kprobe_disabled(p)) { ret = arm_kprobe(p); if (ret) { hlist_del_rcu(&p->hlist); synchronize_rcu(); goto out; } } /* Try to optimize kprobe */ try_to_optimize_kprobe(p); out: mutex_unlock(&kprobe_mutex); if (probed_mod) module_put(probed_mod); return ret; } EXPORT_SYMBOL_GPL(register_kprobe); /* Check if all probes on the aggrprobe are disabled */ static int aggr_kprobe_disabled(struct kprobe *ap) { struct kprobe *kp; lockdep_assert_held(&kprobe_mutex); list_for_each_entry(kp, &ap->list, list) if (!kprobe_disabled(kp)) /* * There is an active probe on the list. * We can't disable this ap. */ return 0; return 1; } /* Disable one kprobe: Make sure called under kprobe_mutex is locked */ static struct kprobe *__disable_kprobe(struct kprobe *p) { struct kprobe *orig_p; int ret; /* Get an original kprobe for return */ orig_p = __get_valid_kprobe(p); if (unlikely(orig_p == NULL)) return ERR_PTR(-EINVAL); if (!kprobe_disabled(p)) { /* Disable probe if it is a child probe */ if (p != orig_p) p->flags |= KPROBE_FLAG_DISABLED; /* Try to disarm and disable this/parent probe */ if (p == orig_p || aggr_kprobe_disabled(orig_p)) { /* * If kprobes_all_disarmed is set, orig_p * should have already been disarmed, so * skip unneed disarming process. */ if (!kprobes_all_disarmed) { ret = disarm_kprobe(orig_p, true); if (ret) { p->flags &= ~KPROBE_FLAG_DISABLED; return ERR_PTR(ret); } } orig_p->flags |= KPROBE_FLAG_DISABLED; } } return orig_p; } /* * Unregister a kprobe without a scheduler synchronization. */ static int __unregister_kprobe_top(struct kprobe *p) { struct kprobe *ap, *list_p; /* Disable kprobe. This will disarm it if needed. */ ap = __disable_kprobe(p); if (IS_ERR(ap)) return PTR_ERR(ap); if (ap == p) /* * This probe is an independent(and non-optimized) kprobe * (not an aggrprobe). Remove from the hash list. */ goto disarmed; /* Following process expects this probe is an aggrprobe */ WARN_ON(!kprobe_aggrprobe(ap)); if (list_is_singular(&ap->list) && kprobe_disarmed(ap)) /* * !disarmed could be happen if the probe is under delayed * unoptimizing. */ goto disarmed; else { /* If disabling probe has special handlers, update aggrprobe */ if (p->post_handler && !kprobe_gone(p)) { list_for_each_entry(list_p, &ap->list, list) { if ((list_p != p) && (list_p->post_handler)) goto noclean; } ap->post_handler = NULL; } noclean: /* * Remove from the aggrprobe: this path will do nothing in * __unregister_kprobe_bottom(). */ list_del_rcu(&p->list); if (!kprobe_disabled(ap) && !kprobes_all_disarmed) /* * Try to optimize this probe again, because post * handler may have been changed. */ optimize_kprobe(ap); } return 0; disarmed: hlist_del_rcu(&ap->hlist); return 0; } static void __unregister_kprobe_bottom(struct kprobe *p) { struct kprobe *ap; if (list_empty(&p->list)) /* This is an independent kprobe */ arch_remove_kprobe(p); else if (list_is_singular(&p->list)) { /* This is the last child of an aggrprobe */ ap = list_entry(p->list.next, struct kprobe, list); list_del(&p->list); free_aggr_kprobe(ap); } /* Otherwise, do nothing. */ } int register_kprobes(struct kprobe **kps, int num) { int i, ret = 0; if (num <= 0) return -EINVAL; for (i = 0; i < num; i++) { ret = register_kprobe(kps[i]); if (ret < 0) { if (i > 0) unregister_kprobes(kps, i); break; } } return ret; } EXPORT_SYMBOL_GPL(register_kprobes); void unregister_kprobe(struct kprobe *p) { unregister_kprobes(&p, 1); } EXPORT_SYMBOL_GPL(unregister_kprobe); void unregister_kprobes(struct kprobe **kps, int num) { int i; if (num <= 0) return; mutex_lock(&kprobe_mutex); for (i = 0; i < num; i++) if (__unregister_kprobe_top(kps[i]) < 0) kps[i]->addr = NULL; mutex_unlock(&kprobe_mutex); synchronize_rcu(); for (i = 0; i < num; i++) if (kps[i]->addr) __unregister_kprobe_bottom(kps[i]); } EXPORT_SYMBOL_GPL(unregister_kprobes); int __weak kprobe_exceptions_notify(struct notifier_block *self, unsigned long val, void *data) { return NOTIFY_DONE; } NOKPROBE_SYMBOL(kprobe_exceptions_notify); static struct notifier_block kprobe_exceptions_nb = { .notifier_call = kprobe_exceptions_notify, .priority = 0x7fffffff /* we need to be notified first */ }; unsigned long __weak arch_deref_entry_point(void *entry) { return (unsigned long)entry; } #ifdef CONFIG_KRETPROBES unsigned long __kretprobe_trampoline_handler(struct pt_regs *regs, void *trampoline_address, void *frame_pointer) { struct kretprobe_instance *ri = NULL, *last = NULL; struct hlist_head *head; struct hlist_node *tmp; unsigned long flags; kprobe_opcode_t *correct_ret_addr = NULL; bool skipped = false; kretprobe_hash_lock(current, &head, &flags); /* * It is possible to have multiple instances associated with a given * task either because multiple functions in the call path have * return probes installed on them, and/or more than one * return probe was registered for a target function. * * We can handle this because: * - instances are always pushed into the head of the list * - when multiple return probes are registered for the same * function, the (chronologically) first instance's ret_addr * will be the real return address, and all the rest will * point to kretprobe_trampoline. */ hlist_for_each_entry(ri, head, hlist) { if (ri->task != current) /* another task is sharing our hash bucket */ continue; /* * Return probes must be pushed on this hash list correct * order (same as return order) so that it can be popped * correctly. However, if we find it is pushed it incorrect * order, this means we find a function which should not be * probed, because the wrong order entry is pushed on the * path of processing other kretprobe itself. */ if (ri->fp != frame_pointer) { if (!skipped) pr_warn("kretprobe is stacked incorrectly. Trying to fixup.\n"); skipped = true; continue; } correct_ret_addr = ri->ret_addr; if (skipped) pr_warn("%ps must be blacklisted because of incorrect kretprobe order\n", ri->rp->kp.addr); if (correct_ret_addr != trampoline_address) /* * This is the real return address. Any other * instances associated with this task are for * other calls deeper on the call stack */ break; } BUG_ON(!correct_ret_addr || (correct_ret_addr == trampoline_address)); last = ri; hlist_for_each_entry_safe(ri, tmp, head, hlist) { if (ri->task != current) /* another task is sharing our hash bucket */ continue; if (ri->fp != frame_pointer) continue; if (ri->rp && ri->rp->handler) { struct kprobe *prev = kprobe_running(); __this_cpu_write(current_kprobe, &ri->rp->kp); ri->ret_addr = correct_ret_addr; ri->rp->handler(ri, regs); __this_cpu_write(current_kprobe, prev); } recycle_rp_inst(ri); if (ri == last) break; } kretprobe_hash_unlock(current, &flags); return (unsigned long)correct_ret_addr; } NOKPROBE_SYMBOL(__kretprobe_trampoline_handler) /* * This kprobe pre_handler is registered with every kretprobe. When probe * hits it will set up the return probe. */ static int pre_handler_kretprobe(struct kprobe *p, struct pt_regs *regs) { struct kretprobe *rp = container_of(p, struct kretprobe, kp); unsigned long hash, flags = 0; struct kretprobe_instance *ri; /* TODO: consider to only swap the RA after the last pre_handler fired */ hash = hash_ptr(current, KPROBE_HASH_BITS); /* * Nested is a workaround that will soon not be needed. * There's other protections that make sure the same lock * is not taken on the same CPU that lockdep is unaware of. */ raw_spin_lock_irqsave_nested(&rp->lock, flags, 1); if (!hlist_empty(&rp->free_instances)) { ri = hlist_entry(rp->free_instances.first, struct kretprobe_instance, hlist); hlist_del(&ri->hlist); raw_spin_unlock_irqrestore(&rp->lock, flags); ri->rp = rp; ri->task = current; if (rp->entry_handler && rp->entry_handler(ri, regs)) { raw_spin_lock_irqsave_nested(&rp->lock, flags, 1); hlist_add_head(&ri->hlist, &rp->free_instances); raw_spin_unlock_irqrestore(&rp->lock, flags); return 0; } arch_prepare_kretprobe(ri, regs); /* XXX(hch): why is there no hlist_move_head? */ INIT_HLIST_NODE(&ri->hlist); kretprobe_table_lock(hash, &flags); hlist_add_head(&ri->hlist, &kretprobe_inst_table[hash]); kretprobe_table_unlock(hash, &flags); } else { rp->nmissed++; raw_spin_unlock_irqrestore(&rp->lock, flags); } return 0; } NOKPROBE_SYMBOL(pre_handler_kretprobe); bool __weak arch_kprobe_on_func_entry(unsigned long offset) { return !offset; } /** * kprobe_on_func_entry() -- check whether given address is function entry * @addr: Target address * @sym: Target symbol name * @offset: The offset from the symbol or the address * * This checks whether the given @addr+@offset or @sym+@offset is on the * function entry address or not. * This returns 0 if it is the function entry, or -EINVAL if it is not. * And also it returns -ENOENT if it fails the symbol or address lookup. * Caller must pass @addr or @sym (either one must be NULL), or this * returns -EINVAL. */ int kprobe_on_func_entry(kprobe_opcode_t *addr, const char *sym, unsigned long offset) { kprobe_opcode_t *kp_addr = _kprobe_addr(addr, sym, offset); if (IS_ERR(kp_addr)) return PTR_ERR(kp_addr); if (!kallsyms_lookup_size_offset((unsigned long)kp_addr, NULL, &offset)) return -ENOENT; if (!arch_kprobe_on_func_entry(offset)) return -EINVAL; return 0; } int register_kretprobe(struct kretprobe *rp) { int ret; struct kretprobe_instance *inst; int i; void *addr; ret = kprobe_on_func_entry(rp->kp.addr, rp->kp.symbol_name, rp->kp.offset); if (ret) return ret; /* If only rp->kp.addr is specified, check reregistering kprobes */ if (rp->kp.addr && check_kprobe_rereg(&rp->kp)) return -EINVAL; if (kretprobe_blacklist_size) { addr = kprobe_addr(&rp->kp); if (IS_ERR(addr)) return PTR_ERR(addr); for (i = 0; kretprobe_blacklist[i].name != NULL; i++) { if (kretprobe_blacklist[i].addr == addr) return -EINVAL; } } if (rp->data_size > KRETPROBE_MAX_DATA_SIZE) return -E2BIG; rp->kp.pre_handler = pre_handler_kretprobe; rp->kp.post_handler = NULL; rp->kp.fault_handler = NULL; /* Pre-allocate memory for max kretprobe instances */ if (rp->maxactive <= 0) { #ifdef CONFIG_PREEMPTION rp->maxactive = max_t(unsigned int, 10, 2*num_possible_cpus()); #else rp->maxactive = num_possible_cpus(); #endif } raw_spin_lock_init(&rp->lock); INIT_HLIST_HEAD(&rp->free_instances); for (i = 0; i < rp->maxactive; i++) { inst = kmalloc(sizeof(struct kretprobe_instance) + rp->data_size, GFP_KERNEL); if (inst == NULL) { free_rp_inst(rp); return -ENOMEM; } INIT_HLIST_NODE(&inst->hlist); hlist_add_head(&inst->hlist, &rp->free_instances); } rp->nmissed = 0; /* Establish function entry probe point */ ret = register_kprobe(&rp->kp); if (ret != 0) free_rp_inst(rp); return ret; } EXPORT_SYMBOL_GPL(register_kretprobe); int register_kretprobes(struct kretprobe **rps, int num) { int ret = 0, i; if (num <= 0) return -EINVAL; for (i = 0; i < num; i++) { ret = register_kretprobe(rps[i]); if (ret < 0) { if (i > 0) unregister_kretprobes(rps, i); break; } } return ret; } EXPORT_SYMBOL_GPL(register_kretprobes); void unregister_kretprobe(struct kretprobe *rp) { unregister_kretprobes(&rp, 1); } EXPORT_SYMBOL_GPL(unregister_kretprobe); void unregister_kretprobes(struct kretprobe **rps, int num) { int i; if (num <= 0) return; mutex_lock(&kprobe_mutex); for (i = 0; i < num; i++) if (__unregister_kprobe_top(&rps[i]->kp) < 0) rps[i]->kp.addr = NULL; mutex_unlock(&kprobe_mutex); synchronize_rcu(); for (i = 0; i < num; i++) { if (rps[i]->kp.addr) { __unregister_kprobe_bottom(&rps[i]->kp); cleanup_rp_inst(rps[i]); } } } EXPORT_SYMBOL_GPL(unregister_kretprobes); #else /* CONFIG_KRETPROBES */ int register_kretprobe(struct kretprobe *rp) { return -ENOSYS; } EXPORT_SYMBOL_GPL(register_kretprobe); int register_kretprobes(struct kretprobe **rps, int num) { return -ENOSYS; } EXPORT_SYMBOL_GPL(register_kretprobes); void unregister_kretprobe(struct kretprobe *rp) { } EXPORT_SYMBOL_GPL(unregister_kretprobe); void unregister_kretprobes(struct kretprobe **rps, int num) { } EXPORT_SYMBOL_GPL(unregister_kretprobes); static int pre_handler_kretprobe(struct kprobe *p, struct pt_regs *regs) { return 0; } NOKPROBE_SYMBOL(pre_handler_kretprobe); #endif /* CONFIG_KRETPROBES */ /* Set the kprobe gone and remove its instruction buffer. */ static void kill_kprobe(struct kprobe *p) { struct kprobe *kp; lockdep_assert_held(&kprobe_mutex); if (WARN_ON_ONCE(kprobe_gone(p))) return; p->flags |= KPROBE_FLAG_GONE; if (kprobe_aggrprobe(p)) { /* * If this is an aggr_kprobe, we have to list all the * chained probes and mark them GONE. */ list_for_each_entry(kp, &p->list, list) kp->flags |= KPROBE_FLAG_GONE; p->post_handler = NULL; kill_optimized_kprobe(p); } /* * Here, we can remove insn_slot safely, because no thread calls * the original probed function (which will be freed soon) any more. */ arch_remove_kprobe(p); /* * The module is going away. We should disarm the kprobe which * is using ftrace, because ftrace framework is still available at * MODULE_STATE_GOING notification. */ if (kprobe_ftrace(p) && !kprobe_disabled(p) && !kprobes_all_disarmed) disarm_kprobe_ftrace(p); } /* Disable one kprobe */ int disable_kprobe(struct kprobe *kp) { int ret = 0; struct kprobe *p; mutex_lock(&kprobe_mutex); /* Disable this kprobe */ p = __disable_kprobe(kp); if (IS_ERR(p)) ret = PTR_ERR(p); mutex_unlock(&kprobe_mutex); return ret; } EXPORT_SYMBOL_GPL(disable_kprobe); /* Enable one kprobe */ int enable_kprobe(struct kprobe *kp) { int ret = 0; struct kprobe *p; mutex_lock(&kprobe_mutex); /* Check whether specified probe is valid. */ p = __get_valid_kprobe(kp); if (unlikely(p == NULL)) { ret = -EINVAL; goto out; } if (kprobe_gone(kp)) { /* This kprobe has gone, we couldn't enable it. */ ret = -EINVAL; goto out; } if (p != kp) kp->flags &= ~KPROBE_FLAG_DISABLED; if (!kprobes_all_disarmed && kprobe_disabled(p)) { p->flags &= ~KPROBE_FLAG_DISABLED; ret = arm_kprobe(p); if (ret) p->flags |= KPROBE_FLAG_DISABLED; } out: mutex_unlock(&kprobe_mutex); return ret; } EXPORT_SYMBOL_GPL(enable_kprobe); /* Caller must NOT call this in usual path. This is only for critical case */ void dump_kprobe(struct kprobe *kp) { pr_err("Dumping kprobe:\n"); pr_err("Name: %s\nOffset: %x\nAddress: %pS\n", kp->symbol_name, kp->offset, kp->addr); } NOKPROBE_SYMBOL(dump_kprobe); int kprobe_add_ksym_blacklist(unsigned long entry) { struct kprobe_blacklist_entry *ent; unsigned long offset = 0, size = 0; if (!kernel_text_address(entry) || !kallsyms_lookup_size_offset(entry, &size, &offset)) return -EINVAL; ent = kmalloc(sizeof(*ent), GFP_KERNEL); if (!ent) return -ENOMEM; ent->start_addr = entry; ent->end_addr = entry + size; INIT_LIST_HEAD(&ent->list); list_add_tail(&ent->list, &kprobe_blacklist); return (int)size; } /* Add all symbols in given area into kprobe blacklist */ int kprobe_add_area_blacklist(unsigned long start, unsigned long end) { unsigned long entry; int ret = 0; for (entry = start; entry < end; entry += ret) { ret = kprobe_add_ksym_blacklist(entry); if (ret < 0) return ret; if (ret == 0) /* In case of alias symbol */ ret = 1; } return 0; } /* Remove all symbols in given area from kprobe blacklist */ static void kprobe_remove_area_blacklist(unsigned long start, unsigned long end) { struct kprobe_blacklist_entry *ent, *n; list_for_each_entry_safe(ent, n, &kprobe_blacklist, list) { if (ent->start_addr < start || ent->start_addr >= end) continue; list_del(&ent->list); kfree(ent); } } static void kprobe_remove_ksym_blacklist(unsigned long entry) { kprobe_remove_area_blacklist(entry, entry + 1); } int __weak arch_kprobe_get_kallsym(unsigned int *symnum, unsigned long *value, char *type, char *sym) { return -ERANGE; } int kprobe_get_kallsym(unsigned int symnum, unsigned long *value, char *type, char *sym) { #ifdef __ARCH_WANT_KPROBES_INSN_SLOT if (!kprobe_cache_get_kallsym(&kprobe_insn_slots, &symnum, value, type, sym)) return 0; #ifdef CONFIG_OPTPROBES if (!kprobe_cache_get_kallsym(&kprobe_optinsn_slots, &symnum, value, type, sym)) return 0; #endif #endif if (!arch_kprobe_get_kallsym(&symnum, value, type, sym)) return 0; return -ERANGE; } int __init __weak arch_populate_kprobe_blacklist(void) { return 0; } /* * Lookup and populate the kprobe_blacklist. * * Unlike the kretprobe blacklist, we'll need to determine * the range of addresses that belong to the said functions, * since a kprobe need not necessarily be at the beginning * of a function. */ static int __init populate_kprobe_blacklist(unsigned long *start, unsigned long *end) { unsigned long entry; unsigned long *iter; int ret; for (iter = start; iter < end; iter++) { entry = arch_deref_entry_point((void *)*iter); ret = kprobe_add_ksym_blacklist(entry); if (ret == -EINVAL) continue; if (ret < 0) return ret; } /* Symbols in __kprobes_text are blacklisted */ ret = kprobe_add_area_blacklist((unsigned long)__kprobes_text_start, (unsigned long)__kprobes_text_end); if (ret) return ret; /* Symbols in noinstr section are blacklisted */ ret = kprobe_add_area_blacklist((unsigned long)__noinstr_text_start, (unsigned long)__noinstr_text_end); return ret ? : arch_populate_kprobe_blacklist(); } static void add_module_kprobe_blacklist(struct module *mod) { unsigned long start, end; int i; if (mod->kprobe_blacklist) { for (i = 0; i < mod->num_kprobe_blacklist; i++) kprobe_add_ksym_blacklist(mod->kprobe_blacklist[i]); } start = (unsigned long)mod->kprobes_text_start; if (start) { end = start + mod->kprobes_text_size; kprobe_add_area_blacklist(start, end); } start = (unsigned long)mod->noinstr_text_start; if (start) { end = start + mod->noinstr_text_size; kprobe_add_area_blacklist(start, end); } } static void remove_module_kprobe_blacklist(struct module *mod) { unsigned long start, end; int i; if (mod->kprobe_blacklist) { for (i = 0; i < mod->num_kprobe_blacklist; i++) kprobe_remove_ksym_blacklist(mod->kprobe_blacklist[i]); } start = (unsigned long)mod->kprobes_text_start; if (start) { end = start + mod->kprobes_text_size; kprobe_remove_area_blacklist(start, end); } start = (unsigned long)mod->noinstr_text_start; if (start) { end = start + mod->noinstr_text_size; kprobe_remove_area_blacklist(start, end); } } /* Module notifier call back, checking kprobes on the module */ static int kprobes_module_callback(struct notifier_block *nb, unsigned long val, void *data) { struct module *mod = data; struct hlist_head *head; struct kprobe *p; unsigned int i; int checkcore = (val == MODULE_STATE_GOING); if (val == MODULE_STATE_COMING) { mutex_lock(&kprobe_mutex); add_module_kprobe_blacklist(mod); mutex_unlock(&kprobe_mutex); } if (val != MODULE_STATE_GOING && val != MODULE_STATE_LIVE) return NOTIFY_DONE; /* * When MODULE_STATE_GOING was notified, both of module .text and * .init.text sections would be freed. When MODULE_STATE_LIVE was * notified, only .init.text section would be freed. We need to * disable kprobes which have been inserted in the sections. */ mutex_lock(&kprobe_mutex); for (i = 0; i < KPROBE_TABLE_SIZE; i++) { head = &kprobe_table[i]; hlist_for_each_entry(p, head, hlist) { if (kprobe_gone(p)) continue; if (within_module_init((unsigned long)p->addr, mod) || (checkcore && within_module_core((unsigned long)p->addr, mod))) { /* * The vaddr this probe is installed will soon * be vfreed buy not synced to disk. Hence, * disarming the breakpoint isn't needed. * * Note, this will also move any optimized probes * that are pending to be removed from their * corresponding lists to the freeing_list and * will not be touched by the delayed * kprobe_optimizer work handler. */ kill_kprobe(p); } } } if (val == MODULE_STATE_GOING) remove_module_kprobe_blacklist(mod); mutex_unlock(&kprobe_mutex); return NOTIFY_DONE; } static struct notifier_block kprobe_module_nb = { .notifier_call = kprobes_module_callback, .priority = 0 }; /* Markers of _kprobe_blacklist section */ extern unsigned long __start_kprobe_blacklist[]; extern unsigned long __stop_kprobe_blacklist[]; void kprobe_free_init_mem(void) { void *start = (void *)(&__init_begin); void *end = (void *)(&__init_end); struct hlist_head *head; struct kprobe *p; int i; mutex_lock(&kprobe_mutex); /* Kill all kprobes on initmem */ for (i = 0; i < KPROBE_TABLE_SIZE; i++) { head = &kprobe_table[i]; hlist_for_each_entry(p, head, hlist) { if (start <= (void *)p->addr && (void *)p->addr < end) kill_kprobe(p); } } mutex_unlock(&kprobe_mutex); } static int __init init_kprobes(void) { int i, err = 0; /* FIXME allocate the probe table, currently defined statically */ /* initialize all list heads */ for (i = 0; i < KPROBE_TABLE_SIZE; i++) { INIT_HLIST_HEAD(&kprobe_table[i]); INIT_HLIST_HEAD(&kretprobe_inst_table[i]); raw_spin_lock_init(&(kretprobe_table_locks[i].lock)); } err = populate_kprobe_blacklist(__start_kprobe_blacklist, __stop_kprobe_blacklist); if (err) { pr_err("kprobes: failed to populate blacklist: %d\n", err); pr_err("Please take care of using kprobes.\n"); } if (kretprobe_blacklist_size) { /* lookup the function address from its name */ for (i = 0; kretprobe_blacklist[i].name != NULL; i++) { kretprobe_blacklist[i].addr = kprobe_lookup_name(kretprobe_blacklist[i].name, 0); if (!kretprobe_blacklist[i].addr) printk("kretprobe: lookup failed: %s\n", kretprobe_blacklist[i].name); } } /* By default, kprobes are armed */ kprobes_all_disarmed = false; #if defined(CONFIG_OPTPROBES) && defined(__ARCH_WANT_KPROBES_INSN_SLOT) /* Init kprobe_optinsn_slots for allocation */ kprobe_optinsn_slots.insn_size = MAX_OPTINSN_SIZE; #endif err = arch_init_kprobes(); if (!err) err = register_die_notifier(&kprobe_exceptions_nb); if (!err) err = register_module_notifier(&kprobe_module_nb); kprobes_initialized = (err == 0); if (!err) init_test_probes(); return err; } early_initcall(init_kprobes); #if defined(CONFIG_OPTPROBES) static int __init init_optprobes(void) { /* * Enable kprobe optimization - this kicks the optimizer which * depends on synchronize_rcu_tasks() and ksoftirqd, that is * not spawned in early initcall. So delay the optimization. */ optimize_all_kprobes(); return 0; } subsys_initcall(init_optprobes); #endif #ifdef CONFIG_DEBUG_FS static void report_probe(struct seq_file *pi, struct kprobe *p, const char *sym, int offset, char *modname, struct kprobe *pp) { char *kprobe_type; void *addr = p->addr; if (p->pre_handler == pre_handler_kretprobe) kprobe_type = "r"; else kprobe_type = "k"; if (!kallsyms_show_value(pi->file->f_cred)) addr = NULL; if (sym) seq_printf(pi, "%px %s %s+0x%x %s ", addr, kprobe_type, sym, offset, (modname ? modname : " ")); else /* try to use %pS */ seq_printf(pi, "%px %s %pS ", addr, kprobe_type, p->addr); if (!pp) pp = p; seq_printf(pi, "%s%s%s%s\n", (kprobe_gone(p) ? "[GONE]" : ""), ((kprobe_disabled(p) && !kprobe_gone(p)) ? "[DISABLED]" : ""), (kprobe_optimized(pp) ? "[OPTIMIZED]" : ""), (kprobe_ftrace(pp) ? "[FTRACE]" : "")); } static void *kprobe_seq_start(struct seq_file *f, loff_t *pos) { return (*pos < KPROBE_TABLE_SIZE) ? pos : NULL; } static void *kprobe_seq_next(struct seq_file *f, void *v, loff_t *pos) { (*pos)++; if (*pos >= KPROBE_TABLE_SIZE) return NULL; return pos; } static void kprobe_seq_stop(struct seq_file *f, void *v) { /* Nothing to do */ } static int show_kprobe_addr(struct seq_file *pi, void *v) { struct hlist_head *head; struct kprobe *p, *kp; const char *sym = NULL; unsigned int i = *(loff_t *) v; unsigned long offset = 0; char *modname, namebuf[KSYM_NAME_LEN]; head = &kprobe_table[i]; preempt_disable(); hlist_for_each_entry_rcu(p, head, hlist) { sym = kallsyms_lookup((unsigned long)p->addr, NULL, &offset, &modname, namebuf); if (kprobe_aggrprobe(p)) { list_for_each_entry_rcu(kp, &p->list, list) report_probe(pi, kp, sym, offset, modname, p); } else report_probe(pi, p, sym, offset, modname, NULL); } preempt_enable(); return 0; } static const struct seq_operations kprobes_sops = { .start = kprobe_seq_start, .next = kprobe_seq_next, .stop = kprobe_seq_stop, .show = show_kprobe_addr }; DEFINE_SEQ_ATTRIBUTE(kprobes); /* kprobes/blacklist -- shows which functions can not be probed */ static void *kprobe_blacklist_seq_start(struct seq_file *m, loff_t *pos) { mutex_lock(&kprobe_mutex); return seq_list_start(&kprobe_blacklist, *pos); } static void *kprobe_blacklist_seq_next(struct seq_file *m, void *v, loff_t *pos) { return seq_list_next(v, &kprobe_blacklist, pos); } static int kprobe_blacklist_seq_show(struct seq_file *m, void *v) { struct kprobe_blacklist_entry *ent = list_entry(v, struct kprobe_blacklist_entry, list); /* * If /proc/kallsyms is not showing kernel address, we won't * show them here either. */ if (!kallsyms_show_value(m->file->f_cred)) seq_printf(m, "0x%px-0x%px\t%ps\n", NULL, NULL, (void *)ent->start_addr); else seq_printf(m, "0x%px-0x%px\t%ps\n", (void *)ent->start_addr, (void *)ent->end_addr, (void *)ent->start_addr); return 0; } static void kprobe_blacklist_seq_stop(struct seq_file *f, void *v) { mutex_unlock(&kprobe_mutex); } static const struct seq_operations kprobe_blacklist_sops = { .start = kprobe_blacklist_seq_start, .next = kprobe_blacklist_seq_next, .stop = kprobe_blacklist_seq_stop, .show = kprobe_blacklist_seq_show, }; DEFINE_SEQ_ATTRIBUTE(kprobe_blacklist); static int arm_all_kprobes(void) { struct hlist_head *head; struct kprobe *p; unsigned int i, total = 0, errors = 0; int err, ret = 0; mutex_lock(&kprobe_mutex); /* If kprobes are armed, just return */ if (!kprobes_all_disarmed) goto already_enabled; /* * optimize_kprobe() called by arm_kprobe() checks * kprobes_all_disarmed, so set kprobes_all_disarmed before * arm_kprobe. */ kprobes_all_disarmed = false; /* Arming kprobes doesn't optimize kprobe itself */ for (i = 0; i < KPROBE_TABLE_SIZE; i++) { head = &kprobe_table[i]; /* Arm all kprobes on a best-effort basis */ hlist_for_each_entry(p, head, hlist) { if (!kprobe_disabled(p)) { err = arm_kprobe(p); if (err) { errors++; ret = err; } total++; } } } if (errors) pr_warn("Kprobes globally enabled, but failed to arm %d out of %d probes\n", errors, total); else pr_info("Kprobes globally enabled\n"); already_enabled: mutex_unlock(&kprobe_mutex); return ret; } static int disarm_all_kprobes(void) { struct hlist_head *head; struct kprobe *p; unsigned int i, total = 0, errors = 0; int err, ret = 0; mutex_lock(&kprobe_mutex); /* If kprobes are already disarmed, just return */ if (kprobes_all_disarmed) { mutex_unlock(&kprobe_mutex); return 0; } kprobes_all_disarmed = true; for (i = 0; i < KPROBE_TABLE_SIZE; i++) { head = &kprobe_table[i]; /* Disarm all kprobes on a best-effort basis */ hlist_for_each_entry(p, head, hlist) { if (!arch_trampoline_kprobe(p) && !kprobe_disabled(p)) { err = disarm_kprobe(p, false); if (err) { errors++; ret = err; } total++; } } } if (errors) pr_warn("Kprobes globally disabled, but failed to disarm %d out of %d probes\n", errors, total); else pr_info("Kprobes globally disabled\n"); mutex_unlock(&kprobe_mutex); /* Wait for disarming all kprobes by optimizer */ wait_for_kprobe_optimizer(); return ret; } /* * XXX: The debugfs bool file interface doesn't allow for callbacks * when the bool state is switched. We can reuse that facility when * available */ static ssize_t read_enabled_file_bool(struct file *file, char __user *user_buf, size_t count, loff_t *ppos) { char buf[3]; if (!kprobes_all_disarmed) buf[0] = '1'; else buf[0] = '0'; buf[1] = '\n'; buf[2] = 0x00; return simple_read_from_buffer(user_buf, count, ppos, buf, 2); } static ssize_t write_enabled_file_bool(struct file *file, const char __user *user_buf, size_t count, loff_t *ppos) { char buf[32]; size_t buf_size; int ret = 0; buf_size = min(count, (sizeof(buf)-1)); if (copy_from_user(buf, user_buf, buf_size)) return -EFAULT; buf[buf_size] = '\0'; switch (buf[0]) { case 'y': case 'Y': case '1': ret = arm_all_kprobes(); break; case 'n': case 'N': case '0': ret = disarm_all_kprobes(); break; default: return -EINVAL; } if (ret) return ret; return count; } static const struct file_operations fops_kp = { .read = read_enabled_file_bool, .write = write_enabled_file_bool, .llseek = default_llseek, }; static int __init debugfs_kprobe_init(void) { struct dentry *dir; dir = debugfs_create_dir("kprobes", NULL); debugfs_create_file("list", 0400, dir, NULL, &kprobes_fops); debugfs_create_file("enabled", 0600, dir, NULL, &fops_kp); debugfs_create_file("blacklist", 0400, dir, NULL, &kprobe_blacklist_fops); return 0; } late_initcall(debugfs_kprobe_init); #endif /* CONFIG_DEBUG_FS */
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 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 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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 // SPDX-License-Identifier: GPL-2.0-or-later /* * Copyright (C) 2008-2014 Mathieu Desnoyers */ #include <linux/module.h> #include <linux/mutex.h> #include <linux/types.h> #include <linux/jhash.h> #include <linux/list.h> #include <linux/rcupdate.h> #include <linux/tracepoint.h> #include <linux/err.h> #include <linux/slab.h> #include <linux/sched/signal.h> #include <linux/sched/task.h> #include <linux/static_key.h> enum tp_func_state { TP_FUNC_0, TP_FUNC_1, TP_FUNC_2, TP_FUNC_N, }; extern tracepoint_ptr_t __start___tracepoints_ptrs[]; extern tracepoint_ptr_t __stop___tracepoints_ptrs[]; DEFINE_SRCU(tracepoint_srcu); EXPORT_SYMBOL_GPL(tracepoint_srcu); enum tp_transition_sync { TP_TRANSITION_SYNC_1_0_1, TP_TRANSITION_SYNC_N_2_1, _NR_TP_TRANSITION_SYNC, }; struct tp_transition_snapshot { unsigned long rcu; unsigned long srcu; bool ongoing; }; /* Protected by tracepoints_mutex */ static struct tp_transition_snapshot tp_transition_snapshot[_NR_TP_TRANSITION_SYNC]; static void tp_rcu_get_state(enum tp_transition_sync sync) { struct tp_transition_snapshot *snapshot = &tp_transition_snapshot[sync]; /* Keep the latest get_state snapshot. */ snapshot->rcu = get_state_synchronize_rcu(); snapshot->srcu = start_poll_synchronize_srcu(&tracepoint_srcu); snapshot->ongoing = true; } static void tp_rcu_cond_sync(enum tp_transition_sync sync) { struct tp_transition_snapshot *snapshot = &tp_transition_snapshot[sync]; if (!snapshot->ongoing) return; cond_synchronize_rcu(snapshot->rcu); if (!poll_state_synchronize_srcu(&tracepoint_srcu, snapshot->srcu)) synchronize_srcu(&tracepoint_srcu); snapshot->ongoing = false; } /* Set to 1 to enable tracepoint debug output */ static const int tracepoint_debug; #ifdef CONFIG_MODULES /* * Tracepoint module list mutex protects the local module list. */ static DEFINE_MUTEX(tracepoint_module_list_mutex); /* Local list of struct tp_module */ static LIST_HEAD(tracepoint_module_list); #endif /* CONFIG_MODULES */ /* * tracepoints_mutex protects the builtin and module tracepoints. * tracepoints_mutex nests inside tracepoint_module_list_mutex. */ static DEFINE_MUTEX(tracepoints_mutex); static struct rcu_head *early_probes; static bool ok_to_free_tracepoints; /* * Note about RCU : * It is used to delay the free of multiple probes array until a quiescent * state is reached. */ struct tp_probes { struct rcu_head rcu; struct tracepoint_func probes[]; }; /* Called in removal of a func but failed to allocate a new tp_funcs */ static void tp_stub_func(void) { return; } static inline void *allocate_probes(int count) { struct tp_probes *p = kmalloc(struct_size(p, probes, count), GFP_KERNEL); return p == NULL ? NULL : p->probes; } static void srcu_free_old_probes(struct rcu_head *head) { kfree(container_of(head, struct tp_probes, rcu)); } static void rcu_free_old_probes(struct rcu_head *head) { call_srcu(&tracepoint_srcu, head, srcu_free_old_probes); } static __init int release_early_probes(void) { struct rcu_head *tmp; ok_to_free_tracepoints = true; while (early_probes) { tmp = early_probes; early_probes = tmp->next; call_rcu(tmp, rcu_free_old_probes); } return 0; } /* SRCU is initialized at core_initcall */ postcore_initcall(release_early_probes); static inline void release_probes(struct tracepoint_func *old) { if (old) { struct tp_probes *tp_probes = container_of(old, struct tp_probes, probes[0]); /* * We can't free probes if SRCU is not initialized yet. * Postpone the freeing till after SRCU is initialized. */ if (unlikely(!ok_to_free_tracepoints)) { tp_probes->rcu.next = early_probes; early_probes = &tp_probes->rcu; return; } /* * Tracepoint probes are protected by both sched RCU and SRCU, * by calling the SRCU callback in the sched RCU callback we * cover both cases. So let us chain the SRCU and sched RCU * callbacks to wait for both grace periods. */ call_rcu(&tp_probes->rcu, rcu_free_old_probes); } } static void debug_print_probes(struct tracepoint_func *funcs) { int i; if (!tracepoint_debug || !funcs) return; for (i = 0; funcs[i].func; i++) printk(KERN_DEBUG "Probe %d : %p\n", i, funcs[i].func); } static struct tracepoint_func * func_add(struct tracepoint_func **funcs, struct tracepoint_func *tp_func, int prio) { struct tracepoint_func *old, *new; int nr_probes = 0; int stub_funcs = 0; int pos = -1; if (WARN_ON(!tp_func->func)) return ERR_PTR(-EINVAL); debug_print_probes(*funcs); old = *funcs; if (old) { /* (N -> N+1), (N != 0, 1) probes */ for (nr_probes = 0; old[nr_probes].func; nr_probes++) { /* Insert before probes of lower priority */ if (pos < 0 && old[nr_probes].prio < prio) pos = nr_probes; if (old[nr_probes].func == tp_func->func && old[nr_probes].data == tp_func->data) return ERR_PTR(-EEXIST); if (old[nr_probes].func == tp_stub_func) stub_funcs++; } } /* + 2 : one for new probe, one for NULL func - stub functions */ new = allocate_probes(nr_probes + 2 - stub_funcs); if (new == NULL) return ERR_PTR(-ENOMEM); if (old) { if (stub_funcs) { /* Need to copy one at a time to remove stubs */ int probes = 0; pos = -1; for (nr_probes = 0; old[nr_probes].func; nr_probes++) { if (old[nr_probes].func == tp_stub_func) continue; if (pos < 0 && old[nr_probes].prio < prio) pos = probes++; new[probes++] = old[nr_probes]; } nr_probes = probes; if (pos < 0) pos = probes; else nr_probes--; /* Account for insertion */ } else if (pos < 0) { pos = nr_probes; memcpy(new, old, nr_probes * sizeof(struct tracepoint_func)); } else { /* Copy higher priority probes ahead of the new probe */ memcpy(new, old, pos * sizeof(struct tracepoint_func)); /* Copy the rest after it. */ memcpy(new + pos + 1, old + pos, (nr_probes - pos) * sizeof(struct tracepoint_func)); } } else pos = 0; new[pos] = *tp_func; new[nr_probes + 1].func = NULL; *funcs = new; debug_print_probes(*funcs); return old; } static void *func_remove(struct tracepoint_func **funcs, struct tracepoint_func *tp_func) { int nr_probes = 0, nr_del = 0, i; struct tracepoint_func *old, *new; old = *funcs; if (!old) return ERR_PTR(-ENOENT); debug_print_probes(*funcs); /* (N -> M), (N > 1, M >= 0) probes */ if (tp_func->func) { for (nr_probes = 0; old[nr_probes].func; nr_probes++) { if ((old[nr_probes].func == tp_func->func && old[nr_probes].data == tp_func->data) || old[nr_probes].func == tp_stub_func) nr_del++; } } /* * If probe is NULL, then nr_probes = nr_del = 0, and then the * entire entry will be removed. */ if (nr_probes - nr_del == 0) { /* N -> 0, (N > 1) */ *funcs = NULL; debug_print_probes(*funcs); return old; } else { int j = 0; /* N -> M, (N > 1, M > 0) */ /* + 1 for NULL */ new = allocate_probes(nr_probes - nr_del + 1); if (new) { for (i = 0; old[i].func; i++) if ((old[i].func != tp_func->func || old[i].data != tp_func->data) && old[i].func != tp_stub_func) new[j++] = old[i]; new[nr_probes - nr_del].func = NULL; *funcs = new; } else { /* * Failed to allocate, replace the old function * with calls to tp_stub_func. */ for (i = 0; old[i].func; i++) if (old[i].func == tp_func->func && old[i].data == tp_func->data) { old[i].func = tp_stub_func; /* Set the prio to the next event. */ if (old[i + 1].func) old[i].prio = old[i + 1].prio; else old[i].prio = -1; } *funcs = old; } } debug_print_probes(*funcs); return old; } /* * Count the number of functions (enum tp_func_state) in a tp_funcs array. */ static enum tp_func_state nr_func_state(const struct tracepoint_func *tp_funcs) { if (!tp_funcs) return TP_FUNC_0; if (!tp_funcs[1].func) return TP_FUNC_1; if (!tp_funcs[2].func) return TP_FUNC_2; return TP_FUNC_N; /* 3 or more */ } static void tracepoint_update_call(struct tracepoint *tp, struct tracepoint_func *tp_funcs) { void *func = tp->iterator; /* Synthetic events do not have static call sites */ if (!tp->static_call_key) return; if (nr_func_state(tp_funcs) == TP_FUNC_1) func = tp_funcs[0].func; __static_call_update(tp->static_call_key, tp->static_call_tramp, func); } /* * Add the probe function to a tracepoint. */ static int tracepoint_add_func(struct tracepoint *tp, struct tracepoint_func *func, int prio, bool warn) { struct tracepoint_func *old, *tp_funcs; int ret; if (tp->regfunc && !static_key_enabled(&tp->key)) { ret = tp->regfunc(); if (ret < 0) return ret; } tp_funcs = rcu_dereference_protected(tp->funcs, lockdep_is_held(&tracepoints_mutex)); old = func_add(&tp_funcs, func, prio); if (IS_ERR(old)) { WARN_ON_ONCE(warn && PTR_ERR(old) != -ENOMEM); return PTR_ERR(old); } /* * rcu_assign_pointer has as smp_store_release() which makes sure * that the new probe callbacks array is consistent before setting * a pointer to it. This array is referenced by __DO_TRACE from * include/linux/tracepoint.h using rcu_dereference_sched(). */ switch (nr_func_state(tp_funcs)) { case TP_FUNC_1: /* 0->1 */ /* * Make sure new static func never uses old data after a * 1->0->1 transition sequence. */ tp_rcu_cond_sync(TP_TRANSITION_SYNC_1_0_1); /* Set static call to first function */ tracepoint_update_call(tp, tp_funcs); /* Both iterator and static call handle NULL tp->funcs */ rcu_assign_pointer(tp->funcs, tp_funcs); static_key_enable(&tp->key); break; case TP_FUNC_2: /* 1->2 */ /* Set iterator static call */ tracepoint_update_call(tp, tp_funcs); /* * Iterator callback installed before updating tp->funcs. * Requires ordering between RCU assign/dereference and * static call update/call. */ fallthrough; case TP_FUNC_N: /* N->N+1 (N>1) */ rcu_assign_pointer(tp->funcs, tp_funcs); /* * Make sure static func never uses incorrect data after a * N->...->2->1 (N>1) transition sequence. */ if (tp_funcs[0].data != old[0].data) tp_rcu_get_state(TP_TRANSITION_SYNC_N_2_1); break; default: WARN_ON_ONCE(1); break; } release_probes(old); return 0; } /* * Remove a probe function from a tracepoint. * Note: only waiting an RCU period after setting elem->call to the empty * function insures that the original callback is not used anymore. This insured * by preempt_disable around the call site. */ static int tracepoint_remove_func(struct tracepoint *tp, struct tracepoint_func *func) { struct tracepoint_func *old, *tp_funcs; tp_funcs = rcu_dereference_protected(tp->funcs, lockdep_is_held(&tracepoints_mutex)); old = func_remove(&tp_funcs, func); if (WARN_ON_ONCE(IS_ERR(old))) return PTR_ERR(old); if (tp_funcs == old) /* Failed allocating new tp_funcs, replaced func with stub */ return 0; switch (nr_func_state(tp_funcs)) { case TP_FUNC_0: /* 1->0 */ /* Removed last function */ if (tp->unregfunc && static_key_enabled(&tp->key)) tp->unregfunc(); static_key_disable(&tp->key); /* Set iterator static call */ tracepoint_update_call(tp, tp_funcs); /* Both iterator and static call handle NULL tp->funcs */ rcu_assign_pointer(tp->funcs, NULL); /* * Make sure new static func never uses old data after a * 1->0->1 transition sequence. */ tp_rcu_get_state(TP_TRANSITION_SYNC_1_0_1); break; case TP_FUNC_1: /* 2->1 */ rcu_assign_pointer(tp->funcs, tp_funcs); /* * Make sure static func never uses incorrect data after a * N->...->2->1 (N>2) transition sequence. If the first * element's data has changed, then force the synchronization * to prevent current readers that have loaded the old data * from calling the new function. */ if (tp_funcs[0].data != old[0].data) tp_rcu_get_state(TP_TRANSITION_SYNC_N_2_1); tp_rcu_cond_sync(TP_TRANSITION_SYNC_N_2_1); /* Set static call to first function */ tracepoint_update_call(tp, tp_funcs); break; case TP_FUNC_2: /* N->N-1 (N>2) */ fallthrough; case TP_FUNC_N: rcu_assign_pointer(tp->funcs, tp_funcs); /* * Make sure static func never uses incorrect data after a * N->...->2->1 (N>2) transition sequence. */ if (tp_funcs[0].data != old[0].data) tp_rcu_get_state(TP_TRANSITION_SYNC_N_2_1); break; default: WARN_ON_ONCE(1); break; } release_probes(old); return 0; } /** * tracepoint_probe_register_prio_may_exist - Connect a probe to a tracepoint with priority * @tp: tracepoint * @probe: probe handler * @data: tracepoint data * @prio: priority of this function over other registered functions * * Same as tracepoint_probe_register_prio() except that it will not warn * if the tracepoint is already registered. */ int tracepoint_probe_register_prio_may_exist(struct tracepoint *tp, void *probe, void *data, int prio) { struct tracepoint_func tp_func; int ret; mutex_lock(&tracepoints_mutex); tp_func.func = probe; tp_func.data = data; tp_func.prio = prio; ret = tracepoint_add_func(tp, &tp_func, prio, false); mutex_unlock(&tracepoints_mutex); return ret; } EXPORT_SYMBOL_GPL(tracepoint_probe_register_prio_may_exist); /** * tracepoint_probe_register_prio - Connect a probe to a tracepoint with priority * @tp: tracepoint * @probe: probe handler * @data: tracepoint data * @prio: priority of this function over other registered functions * * Returns 0 if ok, error value on error. * Note: if @tp is within a module, the caller is responsible for * unregistering the probe before the module is gone. This can be * performed either with a tracepoint module going notifier, or from * within module exit functions. */ int tracepoint_probe_register_prio(struct tracepoint *tp, void *probe, void *data, int prio) { struct tracepoint_func tp_func; int ret; mutex_lock(&tracepoints_mutex); tp_func.func = probe; tp_func.data = data; tp_func.prio = prio; ret = tracepoint_add_func(tp, &tp_func, prio, true); mutex_unlock(&tracepoints_mutex); return ret; } EXPORT_SYMBOL_GPL(tracepoint_probe_register_prio); /** * tracepoint_probe_register - Connect a probe to a tracepoint * @tp: tracepoint * @probe: probe handler * @data: tracepoint data * * Returns 0 if ok, error value on error. * Note: if @tp is within a module, the caller is responsible for * unregistering the probe before the module is gone. This can be * performed either with a tracepoint module going notifier, or from * within module exit functions. */ int tracepoint_probe_register(struct tracepoint *tp, void *probe, void *data) { return tracepoint_probe_register_prio(tp, probe, data, TRACEPOINT_DEFAULT_PRIO); } EXPORT_SYMBOL_GPL(tracepoint_probe_register); /** * tracepoint_probe_unregister - Disconnect a probe from a tracepoint * @tp: tracepoint * @probe: probe function pointer * @data: tracepoint data * * Returns 0 if ok, error value on error. */ int tracepoint_probe_unregister(struct tracepoint *tp, void *probe, void *data) { struct tracepoint_func tp_func; int ret; mutex_lock(&tracepoints_mutex); tp_func.func = probe; tp_func.data = data; ret = tracepoint_remove_func(tp, &tp_func); mutex_unlock(&tracepoints_mutex); return ret; } EXPORT_SYMBOL_GPL(tracepoint_probe_unregister); static void for_each_tracepoint_range( tracepoint_ptr_t *begin, tracepoint_ptr_t *end, void (*fct)(struct tracepoint *tp, void *priv), void *priv) { tracepoint_ptr_t *iter; if (!begin) return; for (iter = begin; iter < end; iter++) fct(tracepoint_ptr_deref(iter), priv); } #ifdef CONFIG_MODULES bool trace_module_has_bad_taint(struct module *mod) { return mod->taints & ~((1 << TAINT_OOT_MODULE) | (1 << TAINT_CRAP) | (1 << TAINT_UNSIGNED_MODULE)); } static BLOCKING_NOTIFIER_HEAD(tracepoint_notify_list); /** * register_tracepoint_notifier - register tracepoint coming/going notifier * @nb: notifier block * * Notifiers registered with this function are called on module * coming/going with the tracepoint_module_list_mutex held. * The notifier block callback should expect a "struct tp_module" data * pointer. */ int register_tracepoint_module_notifier(struct notifier_block *nb) { struct tp_module *tp_mod; int ret; mutex_lock(&tracepoint_module_list_mutex); ret = blocking_notifier_chain_register(&tracepoint_notify_list, nb); if (ret) goto end; list_for_each_entry(tp_mod, &tracepoint_module_list, list) (void) nb->notifier_call(nb, MODULE_STATE_COMING, tp_mod); end: mutex_unlock(&tracepoint_module_list_mutex); return ret; } EXPORT_SYMBOL_GPL(register_tracepoint_module_notifier); /** * unregister_tracepoint_notifier - unregister tracepoint coming/going notifier * @nb: notifier block * * The notifier block callback should expect a "struct tp_module" data * pointer. */ int unregister_tracepoint_module_notifier(struct notifier_block *nb) { struct tp_module *tp_mod; int ret; mutex_lock(&tracepoint_module_list_mutex); ret = blocking_notifier_chain_unregister(&tracepoint_notify_list, nb); if (ret) goto end; list_for_each_entry(tp_mod, &tracepoint_module_list, list) (void) nb->notifier_call(nb, MODULE_STATE_GOING, tp_mod); end: mutex_unlock(&tracepoint_module_list_mutex); return ret; } EXPORT_SYMBOL_GPL(unregister_tracepoint_module_notifier); /* * Ensure the tracer unregistered the module's probes before the module * teardown is performed. Prevents leaks of probe and data pointers. */ static void tp_module_going_check_quiescent(struct tracepoint *tp, void *priv) { WARN_ON_ONCE(tp->funcs); } static int tracepoint_module_coming(struct module *mod) { struct tp_module *tp_mod; int ret = 0; if (!mod->num_tracepoints) return 0; /* * We skip modules that taint the kernel, especially those with different * module headers (for forced load), to make sure we don't cause a crash. * Staging, out-of-tree, and unsigned GPL modules are fine. */ if (trace_module_has_bad_taint(mod)) return 0; mutex_lock(&tracepoint_module_list_mutex); tp_mod = kmalloc(sizeof(struct tp_module), GFP_KERNEL); if (!tp_mod) { ret = -ENOMEM; goto end; } tp_mod->mod = mod; list_add_tail(&tp_mod->list, &tracepoint_module_list); blocking_notifier_call_chain(&tracepoint_notify_list, MODULE_STATE_COMING, tp_mod); end: mutex_unlock(&tracepoint_module_list_mutex); return ret; } static void tracepoint_module_going(struct module *mod) { struct tp_module *tp_mod; if (!mod->num_tracepoints) return; mutex_lock(&tracepoint_module_list_mutex); list_for_each_entry(tp_mod, &tracepoint_module_list, list) { if (tp_mod->mod == mod) { blocking_notifier_call_chain(&tracepoint_notify_list, MODULE_STATE_GOING, tp_mod); list_del(&tp_mod->list); kfree(tp_mod); /* * Called the going notifier before checking for * quiescence. */ for_each_tracepoint_range(mod->tracepoints_ptrs, mod->tracepoints_ptrs + mod->num_tracepoints, tp_module_going_check_quiescent, NULL); break; } } /* * In the case of modules that were tainted at "coming", we'll simply * walk through the list without finding it. We cannot use the "tainted" * flag on "going", in case a module taints the kernel only after being * loaded. */ mutex_unlock(&tracepoint_module_list_mutex); } static int tracepoint_module_notify(struct notifier_block *self, unsigned long val, void *data) { struct module *mod = data; int ret = 0; switch (val) { case MODULE_STATE_COMING: ret = tracepoint_module_coming(mod); break; case MODULE_STATE_LIVE: break; case MODULE_STATE_GOING: tracepoint_module_going(mod); break; case MODULE_STATE_UNFORMED: break; } return notifier_from_errno(ret); } static struct notifier_block tracepoint_module_nb = { .notifier_call = tracepoint_module_notify, .priority = 0, }; static __init int init_tracepoints(void) { int ret; ret = register_module_notifier(&tracepoint_module_nb); if (ret) pr_warn("Failed to register tracepoint module enter notifier\n"); return ret; } __initcall(init_tracepoints); #endif /* CONFIG_MODULES */ /** * for_each_kernel_tracepoint - iteration on all kernel tracepoints * @fct: callback * @priv: private data */ void for_each_kernel_tracepoint(void (*fct)(struct tracepoint *tp, void *priv), void *priv) { for_each_tracepoint_range(__start___tracepoints_ptrs, __stop___tracepoints_ptrs, fct, priv); } EXPORT_SYMBOL_GPL(for_each_kernel_tracepoint); #ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS /* NB: reg/unreg are called while guarded with the tracepoints_mutex */ static int sys_tracepoint_refcount; int syscall_regfunc(void) { struct task_struct *p, *t; if (!sys_tracepoint_refcount) { read_lock(&tasklist_lock); for_each_process_thread(p, t) { set_tsk_thread_flag(t, TIF_SYSCALL_TRACEPOINT); } read_unlock(&tasklist_lock); } sys_tracepoint_refcount++; return 0; } void syscall_unregfunc(void) { struct task_struct *p, *t; sys_tracepoint_refcount--; if (!sys_tracepoint_refcount) { read_lock(&tasklist_lock); for_each_process_thread(p, t) { clear_tsk_thread_flag(t, TIF_SYSCALL_TRACEPOINT); } read_unlock(&tasklist_lock); } } #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 // SPDX-License-Identifier: GPL-2.0 /* * The class-specific portions of the driver model * * Copyright (c) 2001-2003 Patrick Mochel <mochel@osdl.org> * Copyright (c) 2004-2009 Greg Kroah-Hartman <gregkh@suse.de> * Copyright (c) 2008-2009 Novell Inc. * Copyright (c) 2012-2019 Greg Kroah-Hartman <gregkh@linuxfoundation.org> * Copyright (c) 2012-2019 Linux Foundation * * See Documentation/driver-api/driver-model/ for more information. */ #ifndef _DEVICE_CLASS_H_ #define _DEVICE_CLASS_H_ #include <linux/kobject.h> #include <linux/klist.h> #include <linux/pm.h> #include <linux/device/bus.h> struct device; struct fwnode_handle; /** * struct class - device classes * @name: Name of the class. * @owner: The module owner. * @class_groups: Default attributes of this class. * @dev_groups: Default attributes of the devices that belong to the class. * @dev_kobj: The kobject that represents this class and links it into the hierarchy. * @dev_uevent: Called when a device is added, removed from this class, or a * few other things that generate uevents to add the environment * variables. * @devnode: Callback to provide the devtmpfs. * @class_release: Called to release this class. * @dev_release: Called to release the device. * @shutdown_pre: Called at shut-down time before driver shutdown. * @ns_type: Callbacks so sysfs can detemine namespaces. * @namespace: Namespace of the device belongs to this class. * @get_ownership: Allows class to specify uid/gid of the sysfs directories * for the devices belonging to the class. Usually tied to * device's namespace. * @pm: The default device power management operations of this class. * @p: The private data of the driver core, no one other than the * driver core can touch this. * * A class is a higher-level view of a device that abstracts out low-level * implementation details. Drivers may see a SCSI disk or an ATA disk, but, * at the class level, they are all simply disks. Classes allow user space * to work with devices based on what they do, rather than how they are * connected or how they work. */ struct class { const char *name; struct module *owner; const struct attribute_group **class_groups; const struct attribute_group **dev_groups; struct kobject *dev_kobj; int (*dev_uevent)(struct device *dev, struct kobj_uevent_env *env); char *(*devnode)(struct device *dev, umode_t *mode); void (*class_release)(struct class *class); void (*dev_release)(struct device *dev); int (*shutdown_pre)(struct device *dev); const struct kobj_ns_type_operations *ns_type; const void *(*namespace)(struct device *dev); void (*get_ownership)(struct device *dev, kuid_t *uid, kgid_t *gid); const struct dev_pm_ops *pm; struct subsys_private *p; }; struct class_dev_iter { struct klist_iter ki; const struct device_type *type; }; extern struct kobject *sysfs_dev_block_kobj; extern struct kobject *sysfs_dev_char_kobj; extern int __must_check __class_register(struct class *class, struct lock_class_key *key); extern void class_unregister(struct class *class); /* This is a #define to keep the compiler from merging different * instances of the __key variable */ #define class_register(class) \ ({ \ static struct lock_class_key __key; \ __class_register(class, &__key); \ }) struct class_compat; struct class_compat *class_compat_register(const char *name); void class_compat_unregister(struct class_compat *cls); int class_compat_create_link(struct class_compat *cls, struct device *dev, struct device *device_link); void class_compat_remove_link(struct class_compat *cls, struct device *dev, struct device *device_link); extern void class_dev_iter_init(struct class_dev_iter *iter, struct class *class, struct device *start, const struct device_type *type); extern struct device *class_dev_iter_next(struct class_dev_iter *iter); extern void class_dev_iter_exit(struct class_dev_iter *iter); extern int class_for_each_device(struct class *class, struct device *start, void *data, int (*fn)(struct device *dev, void *data)); extern struct device *class_find_device(struct class *class, struct device *start, const void *data, int (*match)(struct device *, const void *)); /** * class_find_device_by_name - device iterator for locating a particular device * of a specific name. * @class: class type * @name: name of the device to match */ static inline struct device *class_find_device_by_name(struct class *class, const char *name) { return class_find_device(class, NULL, name, device_match_name); } /** * class_find_device_by_of_node : device iterator for locating a particular device * matching the of_node. * @class: class type * @np: of_node of the device to match. */ static inline struct device * class_find_device_by_of_node(struct class *class, const struct device_node *np) { return class_find_device(class, NULL, np, device_match_of_node); } /** * class_find_device_by_fwnode : device iterator for locating a particular device * matching the fwnode. * @class: class type * @fwnode: fwnode of the device to match. */ static inline struct device * class_find_device_by_fwnode(struct class *class, const struct fwnode_handle *fwnode) { return class_find_device(class, NULL, fwnode, device_match_fwnode); } /** * class_find_device_by_devt : device iterator for locating a particular device * matching the device type. * @class: class type * @devt: device type of the device to match. */ static inline struct device *class_find_device_by_devt(struct class *class, dev_t devt) { return class_find_device(class, NULL, &devt, device_match_devt); } #ifdef CONFIG_ACPI struct acpi_device; /** * class_find_device_by_acpi_dev : device iterator for locating a particular * device matching the ACPI_COMPANION device. * @class: class type * @adev: ACPI_COMPANION device to match. */ static inline struct device * class_find_device_by_acpi_dev(struct class *class, const struct acpi_device *adev) { return class_find_device(class, NULL, adev, device_match_acpi_dev); } #else static inline struct device * class_find_device_by_acpi_dev(struct class *class, const void *adev) { return NULL; } #endif struct class_attribute { struct attribute attr; ssize_t (*show)(struct class *class, struct class_attribute *attr, char *buf); ssize_t (*store)(struct class *class, struct class_attribute *attr, const char *buf, size_t count); }; #define CLASS_ATTR_RW(_name) \ struct class_attribute class_attr_##_name = __ATTR_RW(_name) #define CLASS_ATTR_RO(_name) \ struct class_attribute class_attr_##_name = __ATTR_RO(_name) #define CLASS_ATTR_WO(_name) \ struct class_attribute class_attr_##_name = __ATTR_WO(_name) extern int __must_check class_create_file_ns(struct class *class, const struct class_attribute *attr, const void *ns); extern void class_remove_file_ns(struct class *class, const struct class_attribute *attr, const void *ns); static inline int __must_check class_create_file(struct class *class, const struct class_attribute *attr) { return class_create_file_ns(class, attr, NULL); } static inline void class_remove_file(struct class *class, const struct class_attribute *attr) { return class_remove_file_ns(class, attr, NULL); } /* Simple class attribute that is just a static string */ struct class_attribute_string { struct class_attribute attr; char *str; }; /* Currently read-only only */ #define _CLASS_ATTR_STRING(_name, _mode, _str) \ { __ATTR(_name, _mode, show_class_attr_string, NULL), _str } #define CLASS_ATTR_STRING(_name, _mode, _str) \ struct class_attribute_string class_attr_##_name = \ _CLASS_ATTR_STRING(_name, _mode, _str) extern ssize_t show_class_attr_string(struct class *class, struct class_attribute *attr, char *buf); struct class_interface { struct list_head node; struct class *class; int (*add_dev) (struct device *, struct class_interface *); void (*remove_dev) (struct device *, struct class_interface *); }; extern int __must_check class_interface_register(struct class_interface *); extern void class_interface_unregister(struct class_interface *); extern struct class * __must_check __class_create(struct module *owner, const char *name, struct lock_class_key *key); extern void class_destroy(struct class *cls); /* This is a #define to keep the compiler from merging different * instances of the __key variable */ #define class_create(owner, name) \ ({ \ static struct lock_class_key __key; \ __class_create(owner, name, &__key); \ }) #endif /* _DEVICE_CLASS_H_ */
1 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 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 /* SPDX-License-Identifier: GPL-2.0+ */ /* * Sleepable Read-Copy Update mechanism for mutual exclusion * * Copyright (C) IBM Corporation, 2006 * Copyright (C) Fujitsu, 2012 * * Author: Paul McKenney <paulmck@linux.ibm.com> * Lai Jiangshan <laijs@cn.fujitsu.com> * * For detailed explanation of Read-Copy Update mechanism see - * Documentation/RCU/ *.txt * */ #ifndef _LINUX_SRCU_H #define _LINUX_SRCU_H #include <linux/mutex.h> #include <linux/rcupdate.h> #include <linux/workqueue.h> #include <linux/rcu_segcblist.h> struct srcu_struct; #ifdef CONFIG_DEBUG_LOCK_ALLOC int __init_srcu_struct(struct srcu_struct *ssp, const char *name, struct lock_class_key *key); #define init_srcu_struct(ssp) \ ({ \ static struct lock_class_key __srcu_key; \ \ __init_srcu_struct((ssp), #ssp, &__srcu_key); \ }) #define __SRCU_DEP_MAP_INIT(srcu_name) .dep_map = { .name = #srcu_name }, #else /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */ int init_srcu_struct(struct srcu_struct *ssp); #define __SRCU_DEP_MAP_INIT(srcu_name) #endif /* #else #ifdef CONFIG_DEBUG_LOCK_ALLOC */ #ifdef CONFIG_TINY_SRCU #include <linux/srcutiny.h> #elif defined(CONFIG_TREE_SRCU) #include <linux/srcutree.h> #elif defined(CONFIG_SRCU) #error "Unknown SRCU implementation specified to kernel configuration" #else /* Dummy definition for things like notifiers. Actual use gets link error. */ struct srcu_struct { }; #endif void call_srcu(struct srcu_struct *ssp, struct rcu_head *head, void (*func)(struct rcu_head *head)); void cleanup_srcu_struct(struct srcu_struct *ssp); int __srcu_read_lock(struct srcu_struct *ssp) __acquires(ssp); void __srcu_read_unlock(struct srcu_struct *ssp, int idx) __releases(ssp); void synchronize_srcu(struct srcu_struct *ssp); unsigned long get_state_synchronize_srcu(struct srcu_struct *ssp); unsigned long start_poll_synchronize_srcu(struct srcu_struct *ssp); bool poll_state_synchronize_srcu(struct srcu_struct *ssp, unsigned long cookie); #ifdef CONFIG_DEBUG_LOCK_ALLOC /** * srcu_read_lock_held - might we be in SRCU read-side critical section? * @ssp: The srcu_struct structure to check * * If CONFIG_DEBUG_LOCK_ALLOC is selected, returns nonzero iff in an SRCU * read-side critical section. In absence of CONFIG_DEBUG_LOCK_ALLOC, * this assumes we are in an SRCU read-side critical section unless it can * prove otherwise. * * Checks debug_lockdep_rcu_enabled() to prevent false positives during boot * and while lockdep is disabled. * * Note that SRCU is based on its own statemachine and it doesn't * relies on normal RCU, it can be called from the CPU which * is in the idle loop from an RCU point of view or offline. */ static inline int srcu_read_lock_held(const struct srcu_struct *ssp) { if (!debug_lockdep_rcu_enabled()) return 1; return lock_is_held(&ssp->dep_map); } #else /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */ static inline int srcu_read_lock_held(const struct srcu_struct *ssp) { return 1; } #endif /* #else #ifdef CONFIG_DEBUG_LOCK_ALLOC */ /** * srcu_dereference_check - fetch SRCU-protected pointer for later dereferencing * @p: the pointer to fetch and protect for later dereferencing * @ssp: pointer to the srcu_struct, which is used to check that we * really are in an SRCU read-side critical section. * @c: condition to check for update-side use * * If PROVE_RCU is enabled, invoking this outside of an RCU read-side * critical section will result in an RCU-lockdep splat, unless @c evaluates * to 1. The @c argument will normally be a logical expression containing * lockdep_is_held() calls. */ #define srcu_dereference_check(p, ssp, c) \ __rcu_dereference_check((p), (c) || srcu_read_lock_held(ssp), __rcu) /** * srcu_dereference - fetch SRCU-protected pointer for later dereferencing * @p: the pointer to fetch and protect for later dereferencing * @ssp: pointer to the srcu_struct, which is used to check that we * really are in an SRCU read-side critical section. * * Makes rcu_dereference_check() do the dirty work. If PROVE_RCU * is enabled, invoking this outside of an RCU read-side critical * section will result in an RCU-lockdep splat. */ #define srcu_dereference(p, ssp) srcu_dereference_check((p), (ssp), 0) /** * srcu_dereference_notrace - no tracing and no lockdep calls from here * @p: the pointer to fetch and protect for later dereferencing * @ssp: pointer to the srcu_struct, which is used to check that we * really are in an SRCU read-side critical section. */ #define srcu_dereference_notrace(p, ssp) srcu_dereference_check((p), (ssp), 1) /** * srcu_read_lock - register a new reader for an SRCU-protected structure. * @ssp: srcu_struct in which to register the new reader. * * Enter an SRCU read-side critical section. Note that SRCU read-side * critical sections may be nested. However, it is illegal to * call anything that waits on an SRCU grace period for the same * srcu_struct, whether directly or indirectly. Please note that * one way to indirectly wait on an SRCU grace period is to acquire * a mutex that is held elsewhere while calling synchronize_srcu() or * synchronize_srcu_expedited(). * * Note that srcu_read_lock() and the matching srcu_read_unlock() must * occur in the same context, for example, it is illegal to invoke * srcu_read_unlock() in an irq handler if the matching srcu_read_lock() * was invoked in process context. */ static inline int srcu_read_lock(struct srcu_struct *ssp) __acquires(ssp) { int retval; retval = __srcu_read_lock(ssp); rcu_lock_acquire(&(ssp)->dep_map); return retval; } /* Used by tracing, cannot be traced and cannot invoke lockdep. */ static inline notrace int srcu_read_lock_notrace(struct srcu_struct *ssp) __acquires(ssp) { int retval; retval = __srcu_read_lock(ssp); return retval; } /** * srcu_read_unlock - unregister a old reader from an SRCU-protected structure. * @ssp: srcu_struct in which to unregister the old reader. * @idx: return value from corresponding srcu_read_lock(). * * Exit an SRCU read-side critical section. */ static inline void srcu_read_unlock(struct srcu_struct *ssp, int idx) __releases(ssp) { WARN_ON_ONCE(idx & ~0x1); rcu_lock_release(&(ssp)->dep_map); __srcu_read_unlock(ssp, idx); } /* Used by tracing, cannot be traced and cannot call lockdep. */ static inline notrace void srcu_read_unlock_notrace(struct srcu_struct *ssp, int idx) __releases(ssp) { __srcu_read_unlock(ssp, idx); } /** * smp_mb__after_srcu_read_unlock - ensure full ordering after srcu_read_unlock * * Converts the preceding srcu_read_unlock into a two-way memory barrier. * * Call this after srcu_read_unlock, to guarantee that all memory operations * that occur after smp_mb__after_srcu_read_unlock will appear to happen after * the preceding srcu_read_unlock. */ static inline void smp_mb__after_srcu_read_unlock(void) { /* __srcu_read_unlock has smp_mb() internally so nothing to do here. */ } #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 /* SPDX-License-Identifier: GPL-2.0 */ #ifndef _ASM_X86_ATOMIC64_64_H #define _ASM_X86_ATOMIC64_64_H #include <linux/types.h> #include <asm/alternative.h> #include <asm/cmpxchg.h> /* The 64-bit atomic type */ #define ATOMIC64_INIT(i) { (i) } /** * arch_atomic64_read - read atomic64 variable * @v: pointer of type atomic64_t * * Atomically reads the value of @v. * Doesn't imply a read memory barrier. */ static inline s64 arch_atomic64_read(const atomic64_t *v) { return __READ_ONCE((v)->counter); } /** * arch_atomic64_set - set atomic64 variable * @v: pointer to type atomic64_t * @i: required value * * Atomically sets the value of @v to @i. */ static inline void arch_atomic64_set(atomic64_t *v, s64 i) { __WRITE_ONCE(v->counter, i); } /** * arch_atomic64_add - add integer to atomic64 variable * @i: integer value to add * @v: pointer to type atomic64_t * * Atomically adds @i to @v. */ static __always_inline void arch_atomic64_add(s64 i, atomic64_t *v) { asm volatile(LOCK_PREFIX "addq %1,%0" : "=m" (v->counter) : "er" (i), "m" (v->counter) : "memory"); } /** * arch_atomic64_sub - subtract the atomic64 variable * @i: integer value to subtract * @v: pointer to type atomic64_t * * Atomically subtracts @i from @v. */ static inline void arch_atomic64_sub(s64 i, atomic64_t *v) { asm volatile(LOCK_PREFIX "subq %1,%0" : "=m" (v->counter) : "er" (i), "m" (v->counter) : "memory"); } /** * arch_atomic64_sub_and_test - subtract value from variable and test result * @i: integer value to subtract * @v: pointer to type atomic64_t * * Atomically subtracts @i from @v and returns * true if the result is zero, or false for all * other cases. */ static inline bool arch_atomic64_sub_and_test(s64 i, atomic64_t *v) { return GEN_BINARY_RMWcc(LOCK_PREFIX "subq", v->counter, e, "er", i); } #define arch_atomic64_sub_and_test arch_atomic64_sub_and_test /** * arch_atomic64_inc - increment atomic64 variable * @v: pointer to type atomic64_t * * Atomically increments @v by 1. */ static __always_inline void arch_atomic64_inc(atomic64_t *v) { asm volatile(LOCK_PREFIX "incq %0" : "=m" (v->counter) : "m" (v->counter) : "memory"); } #define arch_atomic64_inc arch_atomic64_inc /** * arch_atomic64_dec - decrement atomic64 variable * @v: pointer to type atomic64_t * * Atomically decrements @v by 1. */ static __always_inline void arch_atomic64_dec(atomic64_t *v) { asm volatile(LOCK_PREFIX "decq %0" : "=m" (v->counter) : "m" (v->counter) : "memory"); } #define arch_atomic64_dec arch_atomic64_dec /** * arch_atomic64_dec_and_test - decrement and test * @v: pointer to type atomic64_t * * Atomically decrements @v by 1 and * returns true if the result is 0, or false for all other * cases. */ static inline bool arch_atomic64_dec_and_test(atomic64_t *v) { return GEN_UNARY_RMWcc(LOCK_PREFIX "decq", v->counter, e); } #define arch_atomic64_dec_and_test arch_atomic64_dec_and_test /** * arch_atomic64_inc_and_test - increment and test * @v: pointer to type atomic64_t * * Atomically increments @v by 1 * and returns true if the result is zero, or false for all * other cases. */ static inline bool arch_atomic64_inc_and_test(atomic64_t *v) { return GEN_UNARY_RMWcc(LOCK_PREFIX "incq", v->counter, e); } #define arch_atomic64_inc_and_test arch_atomic64_inc_and_test /** * arch_atomic64_add_negative - add and test if negative * @i: integer value to add * @v: pointer to type atomic64_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 inline bool arch_atomic64_add_negative(s64 i, atomic64_t *v) { return GEN_BINARY_RMWcc(LOCK_PREFIX "addq", v->counter, s, "er", i); } #define arch_atomic64_add_negative arch_atomic64_add_negative /** * arch_atomic64_add_return - add and return * @i: integer value to add * @v: pointer to type atomic64_t * * Atomically adds @i to @v and returns @i + @v */ static __always_inline s64 arch_atomic64_add_return(s64 i, atomic64_t *v) { return i + xadd(&v->counter, i); } #define arch_atomic64_add_return arch_atomic64_add_return static inline s64 arch_atomic64_sub_return(s64 i, atomic64_t *v) { return arch_atomic64_add_return(-i, v); } #define arch_atomic64_sub_return arch_atomic64_sub_return static inline s64 arch_atomic64_fetch_add(s64 i, atomic64_t *v) { return xadd(&v->counter, i); } #define arch_atomic64_fetch_add arch_atomic64_fetch_add static inline s64 arch_atomic64_fetch_sub(s64 i, atomic64_t *v) { return xadd(&v->counter, -i); } #define arch_atomic64_fetch_sub arch_atomic64_fetch_sub static inline s64 arch_atomic64_cmpxchg(atomic64_t *v, s64 old, s64 new) { return arch_cmpxchg(&v->counter, old, new); } #define arch_atomic64_cmpxchg arch_atomic64_cmpxchg static __always_inline bool arch_atomic64_try_cmpxchg(atomic64_t *v, s64 *old, s64 new) { return try_cmpxchg(&v->counter, old, new); } #define arch_atomic64_try_cmpxchg arch_atomic64_try_cmpxchg static inline s64 arch_atomic64_xchg(atomic64_t *v, s64 new) { return arch_xchg(&v->counter, new); } #define arch_atomic64_xchg arch_atomic64_xchg static inline void arch_atomic64_and(s64 i, atomic64_t *v) { asm volatile(LOCK_PREFIX "andq %1,%0" : "+m" (v->counter) : "er" (i) : "memory"); } static inline s64 arch_atomic64_fetch_and(s64 i, atomic64_t *v) { s64 val = arch_atomic64_read(v); do { } while (!arch_atomic64_try_cmpxchg(v, &val, val & i)); return val; } #define arch_atomic64_fetch_and arch_atomic64_fetch_and static inline void arch_atomic64_or(s64 i, atomic64_t *v) { asm volatile(LOCK_PREFIX "orq %1,%0" : "+m" (v->counter) : "er" (i) : "memory"); } static inline s64 arch_atomic64_fetch_or(s64 i, atomic64_t *v) { s64 val = arch_atomic64_read(v); do { } while (!arch_atomic64_try_cmpxchg(v, &val, val | i)); return val; } #define arch_atomic64_fetch_or arch_atomic64_fetch_or static inline void arch_atomic64_xor(s64 i, atomic64_t *v) { asm volatile(LOCK_PREFIX "xorq %1,%0" : "+m" (v->counter) : "er" (i) : "memory"); } static inline s64 arch_atomic64_fetch_xor(s64 i, atomic64_t *v) { s64 val = arch_atomic64_read(v); do { } while (!arch_atomic64_try_cmpxchg(v, &val, val ^ i)); return val; } #define arch_atomic64_fetch_xor arch_atomic64_fetch_xor #endif /* _ASM_X86_ATOMIC64_64_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 /* SPDX-License-Identifier: GPL-2.0 */ #ifndef __LINUX_PREEMPT_H #define __LINUX_PREEMPT_H /* * include/linux/preempt.h - macros for accessing and manipulating * preempt_count (used for kernel preemption, interrupt count, etc.) */ #include <linux/linkage.h> #include <linux/list.h> /* * We put the hardirq and softirq counter into the preemption * counter. The bitmask has the following meaning: * * - bits 0-7 are the preemption count (max preemption depth: 256) * - bits 8-15 are the softirq count (max # of softirqs: 256) * * The hardirq count could in theory be the same as the number of * interrupts in the system, but we run all interrupt handlers with * interrupts disabled, so we cannot have nesting interrupts. Though * there are a few palaeontologic drivers which reenable interrupts in * the handler, so we need more than one bit here. * * PREEMPT_MASK: 0x000000ff * SOFTIRQ_MASK: 0x0000ff00 * HARDIRQ_MASK: 0x000f0000 * NMI_MASK: 0x00f00000 * PREEMPT_NEED_RESCHED: 0x80000000 */ #define PREEMPT_BITS 8 #define SOFTIRQ_BITS 8 #define HARDIRQ_BITS 4 #define NMI_BITS 4 #define PREEMPT_SHIFT 0 #define SOFTIRQ_SHIFT (PREEMPT_SHIFT + PREEMPT_BITS) #define HARDIRQ_SHIFT (SOFTIRQ_SHIFT + SOFTIRQ_BITS) #define NMI_SHIFT (HARDIRQ_SHIFT + HARDIRQ_BITS) #define __IRQ_MASK(x) ((1UL << (x))-1) #define PREEMPT_MASK (__IRQ_MASK(PREEMPT_BITS) << PREEMPT_SHIFT) #define SOFTIRQ_MASK (__IRQ_MASK(SOFTIRQ_BITS) << SOFTIRQ_SHIFT) #define HARDIRQ_MASK (__IRQ_MASK(HARDIRQ_BITS) << HARDIRQ_SHIFT) #define NMI_MASK (__IRQ_MASK(NMI_BITS) << NMI_SHIFT) #define PREEMPT_OFFSET (1UL << PREEMPT_SHIFT) #define SOFTIRQ_OFFSET (1UL << SOFTIRQ_SHIFT) #define HARDIRQ_OFFSET (1UL << HARDIRQ_SHIFT) #define NMI_OFFSET (1UL << NMI_SHIFT) #define SOFTIRQ_DISABLE_OFFSET (2 * SOFTIRQ_OFFSET) #define PREEMPT_DISABLED (PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED) /* * Disable preemption until the scheduler is running -- use an unconditional * value so that it also works on !PREEMPT_COUNT kernels. * * Reset by start_kernel()->sched_init()->init_idle()->init_idle_preempt_count(). */ #define INIT_PREEMPT_COUNT PREEMPT_OFFSET /* * Initial preempt_count value; reflects the preempt_count schedule invariant * which states that during context switches: * * preempt_count() == 2*PREEMPT_DISABLE_OFFSET * * Note: PREEMPT_DISABLE_OFFSET is 0 for !PREEMPT_COUNT kernels. * Note: See finish_task_switch(). */ #define FORK_PREEMPT_COUNT (2*PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED) /* preempt_count() and related functions, depends on PREEMPT_NEED_RESCHED */ #include <asm/preempt.h> #define hardirq_count() (preempt_count() & HARDIRQ_MASK) #define softirq_count() (preempt_count() & SOFTIRQ_MASK) #define irq_count() (preempt_count() & (HARDIRQ_MASK | SOFTIRQ_MASK \ | NMI_MASK)) /* * Are we doing bottom half or hardware interrupt processing? * * in_irq() - We're in (hard) IRQ context * in_softirq() - We have BH disabled, or are processing softirqs * in_interrupt() - We're in NMI,IRQ,SoftIRQ context or have BH disabled * in_serving_softirq() - We're in softirq context * in_nmi() - We're in NMI context * in_task() - We're in task context * * Note: due to the BH disabled confusion: in_softirq(),in_interrupt() really * should not be used in new code. */ #define in_irq() (hardirq_count()) #define in_softirq() (softirq_count()) #define in_interrupt() (irq_count()) #define in_serving_softirq() (softirq_count() & SOFTIRQ_OFFSET) #define in_nmi() (preempt_count() & NMI_MASK) #define in_task() (!(preempt_count() & \ (NMI_MASK | HARDIRQ_MASK | SOFTIRQ_OFFSET))) /* * The preempt_count offset after preempt_disable(); */ #if defined(CONFIG_PREEMPT_COUNT) # define PREEMPT_DISABLE_OFFSET PREEMPT_OFFSET #else # define PREEMPT_DISABLE_OFFSET 0 #endif /* * The preempt_count offset after spin_lock() */ #define PREEMPT_LOCK_OFFSET PREEMPT_DISABLE_OFFSET /* * The preempt_count offset needed for things like: * * spin_lock_bh() * * Which need to disable both preemption (CONFIG_PREEMPT_COUNT) and * softirqs, such that unlock sequences of: * * spin_unlock(); * local_bh_enable(); * * Work as expected. */ #define SOFTIRQ_LOCK_OFFSET (SOFTIRQ_DISABLE_OFFSET + PREEMPT_LOCK_OFFSET) /* * Are we running in atomic context? WARNING: this macro cannot * always detect atomic context; in particular, it cannot know about * held spinlocks in non-preemptible kernels. Thus it should not be * used in the general case to determine whether sleeping is possible. * Do not use in_atomic() in driver code. */ #define in_atomic() (preempt_count() != 0) /* * Check whether we were atomic before we did preempt_disable(): * (used by the scheduler) */ #define in_atomic_preempt_off() (preempt_count() != PREEMPT_DISABLE_OFFSET) #if defined(CONFIG_DEBUG_PREEMPT) || defined(CONFIG_TRACE_PREEMPT_TOGGLE) extern void preempt_count_add(int val); extern void preempt_count_sub(int val); #define preempt_count_dec_and_test() \ ({ preempt_count_sub(1); should_resched(0); }) #else #define preempt_count_add(val) __preempt_count_add(val) #define preempt_count_sub(val) __preempt_count_sub(val) #define preempt_count_dec_and_test() __preempt_count_dec_and_test() #endif #define __preempt_count_inc() __preempt_count_add(1) #define __preempt_count_dec() __preempt_count_sub(1) #define preempt_count_inc() preempt_count_add(1) #define preempt_count_dec() preempt_count_sub(1) #ifdef CONFIG_PREEMPT_COUNT #define preempt_disable() \ do { \ preempt_count_inc(); \ barrier(); \ } while (0) #define sched_preempt_enable_no_resched() \ do { \ barrier(); \ preempt_count_dec(); \ } while (0) #define preempt_enable_no_resched() sched_preempt_enable_no_resched() #define preemptible() (preempt_count() == 0 && !irqs_disabled()) #ifdef CONFIG_PREEMPTION #define preempt_enable() \ do { \ barrier(); \ if (unlikely(preempt_count_dec_and_test())) \ __preempt_schedule(); \ } while (0) #define preempt_enable_notrace() \ do { \ barrier(); \ if (unlikely(__preempt_count_dec_and_test())) \ __preempt_schedule_notrace(); \ } while (0) #define preempt_check_resched() \ do { \ if (should_resched(0)) \ __preempt_schedule(); \ } while (0) #else /* !CONFIG_PREEMPTION */ #define preempt_enable() \ do { \ barrier(); \ preempt_count_dec(); \ } while (0) #define preempt_enable_notrace() \ do { \ barrier(); \ __preempt_count_dec(); \ } while (0) #define preempt_check_resched() do { } while (0) #endif /* CONFIG_PREEMPTION */ #define preempt_disable_notrace() \ do { \ __preempt_count_inc(); \ barrier(); \ } while (0) #define preempt_enable_no_resched_notrace() \ do { \ barrier(); \ __preempt_count_dec(); \ } while (0) #else /* !CONFIG_PREEMPT_COUNT */ /* * Even if we don't have any preemption, we need preempt disable/enable * to be barriers, so that we don't have things like get_user/put_user * that can cause faults and scheduling migrate into our preempt-protected * region. */ #define preempt_disable() barrier() #define sched_preempt_enable_no_resched() barrier() #define preempt_enable_no_resched() barrier() #define preempt_enable() barrier() #define preempt_check_resched() do { } while (0) #define preempt_disable_notrace() barrier() #define preempt_enable_no_resched_notrace() barrier() #define preempt_enable_notrace() barrier() #define preemptible() 0 #endif /* CONFIG_PREEMPT_COUNT */ #ifdef MODULE /* * Modules have no business playing preemption tricks. */ #undef sched_preempt_enable_no_resched #undef preempt_enable_no_resched #undef preempt_enable_no_resched_notrace #undef preempt_check_resched #endif #define preempt_set_need_resched() \ do { \ set_preempt_need_resched(); \ } while (0) #define preempt_fold_need_resched() \ do { \ if (tif_need_resched()) \ set_preempt_need_resched(); \ } while (0) #ifdef CONFIG_PREEMPT_NOTIFIERS struct preempt_notifier; /** * preempt_ops - notifiers called when a task is preempted and rescheduled * @sched_in: we're about to be rescheduled: * notifier: struct preempt_notifier for the task being scheduled * cpu: cpu we're scheduled on * @sched_out: we've just been preempted * notifier: struct preempt_notifier for the task being preempted * next: the task that's kicking us out * * Please note that sched_in and out are called under different * contexts. sched_out is called with rq lock held and irq disabled * while sched_in is called without rq lock and irq enabled. This * difference is intentional and depended upon by its users. */ struct preempt_ops { void (*sched_in)(struct preempt_notifier *notifier, int cpu); void (*sched_out)(struct preempt_notifier *notifier, struct task_struct *next); }; /** * preempt_notifier - key for installing preemption notifiers * @link: internal use * @ops: defines the notifier functions to be called * * Usually used in conjunction with container_of(). */ struct preempt_notifier { struct hlist_node link; struct preempt_ops *ops; }; void preempt_notifier_inc(void); void preempt_notifier_dec(void); void preempt_notifier_register(struct preempt_notifier *notifier); void preempt_notifier_unregister(struct preempt_notifier *notifier); static inline void preempt_notifier_init(struct preempt_notifier *notifier, struct preempt_ops *ops) { INIT_HLIST_NODE(&notifier->link); notifier->ops = ops; } #endif /** * migrate_disable - Prevent migration of the current task * * Maps to preempt_disable() which also disables preemption. Use * migrate_disable() to annotate that the intent is to prevent migration, * but not necessarily preemption. * * Can be invoked nested like preempt_disable() and needs the corresponding * number of migrate_enable() invocations. */ static __always_inline void migrate_disable(void) { preempt_disable(); } /** * migrate_enable - Allow migration of the current task * * Counterpart to migrate_disable(). * * As migrate_disable() can be invoked nested, only the outermost invocation * reenables migration. * * Currently mapped to preempt_enable(). */ static __always_inline void migrate_enable(void) { preempt_enable(); } #endif /* __LINUX_PREEMPT_H */
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3621 3622 3623 3624 3625 3626 3627 3628 3629 3630 3631 3632 3633 3634 3635 3636 3637 3638 3639 3640 3641 3642 3643 3644 3645 3646 3647 3648 3649 3650 3651 3652 3653 3654 3655 3656 3657 3658 3659 3660 3661 3662 3663 3664 3665 3666 3667 3668 3669 3670 3671 3672 3673 3674 3675 3676 3677 3678 3679 3680 3681 3682 3683 3684 3685 3686 3687 3688 3689 3690 3691 3692 3693 3694 3695 3696 3697 3698 3699 3700 3701 3702 3703 3704 3705 3706 3707 3708 3709 3710 3711 3712 3713 3714 3715 3716 3717 3718 3719 3720 3721 3722 3723 3724 3725 3726 3727 3728 3729 3730 3731 3732 3733 3734 3735 3736 3737 3738 3739 3740 3741 3742 3743 3744 3745 3746 3747 3748 3749 3750 3751 3752 3753 3754 3755 3756 3757 3758 3759 3760 3761 3762 3763 3764 // SPDX-License-Identifier: GPL-2.0 /* * event tracer * * Copyright (C) 2008 Red Hat Inc, Steven Rostedt <srostedt@redhat.com> * * - Added format output of fields of the trace point. * This was based off of work by Tom Zanussi <tzanussi@gmail.com>. * */ #define pr_fmt(fmt) fmt #include <linux/workqueue.h> #include <linux/security.h> #include <linux/spinlock.h> #include <linux/kthread.h> #include <linux/tracefs.h> #include <linux/uaccess.h> #include <linux/module.h> #include <linux/ctype.h> #include <linux/sort.h> #include <linux/slab.h> #include <linux/delay.h> #include <trace/events/sched.h> #include <trace/syscall.h> #include <asm/setup.h> #include "trace_output.h" #undef TRACE_SYSTEM #define TRACE_SYSTEM "TRACE_SYSTEM" DEFINE_MUTEX(event_mutex); LIST_HEAD(ftrace_events); static LIST_HEAD(ftrace_generic_fields); static LIST_HEAD(ftrace_common_fields); static bool eventdir_initialized; #define GFP_TRACE (GFP_KERNEL | __GFP_ZERO) static struct kmem_cache *field_cachep; static struct kmem_cache *file_cachep; static inline int system_refcount(struct event_subsystem *system) { return system->ref_count; } static int system_refcount_inc(struct event_subsystem *system) { return system->ref_count++; } static int system_refcount_dec(struct event_subsystem *system) { return --system->ref_count; } /* Double loops, do not use break, only goto's work */ #define do_for_each_event_file(tr, file) \ list_for_each_entry(tr, &ftrace_trace_arrays, list) { \ list_for_each_entry(file, &tr->events, list) #define do_for_each_event_file_safe(tr, file) \ list_for_each_entry(tr, &ftrace_trace_arrays, list) { \ struct trace_event_file *___n; \ list_for_each_entry_safe(file, ___n, &tr->events, list) #define while_for_each_event_file() \ } static struct ftrace_event_field * __find_event_field(struct list_head *head, char *name) { struct ftrace_event_field *field; list_for_each_entry(field, head, link) { if (!strcmp(field->name, name)) return field; } return NULL; } struct ftrace_event_field * trace_find_event_field(struct trace_event_call *call, char *name) { struct ftrace_event_field *field; struct list_head *head; head = trace_get_fields(call); field = __find_event_field(head, name); if (field) return field; field = __find_event_field(&ftrace_generic_fields, name); if (field) return field; return __find_event_field(&ftrace_common_fields, name); } static int __trace_define_field(struct list_head *head, const char *type, const char *name, int offset, int size, int is_signed, int filter_type) { struct ftrace_event_field *field; field = kmem_cache_alloc(field_cachep, GFP_TRACE); if (!field) return -ENOMEM; field->name = name; field->type = type; if (filter_type == FILTER_OTHER) field->filter_type = filter_assign_type(type); else field->filter_type = filter_type; field->offset = offset; field->size = size; field->is_signed = is_signed; list_add(&field->link, head); return 0; } int trace_define_field(struct trace_event_call *call, const char *type, const char *name, int offset, int size, int is_signed, int filter_type) { struct list_head *head; if (WARN_ON(!call->class)) return 0; head = trace_get_fields(call); return __trace_define_field(head, type, name, offset, size, is_signed, filter_type); } EXPORT_SYMBOL_GPL(trace_define_field); #define __generic_field(type, item, filter_type) \ ret = __trace_define_field(&ftrace_generic_fields, #type, \ #item, 0, 0, is_signed_type(type), \ filter_type); \ if (ret) \ return ret; #define __common_field(type, item) \ ret = __trace_define_field(&ftrace_common_fields, #type, \ "common_" #item, \ offsetof(typeof(ent), item), \ sizeof(ent.item), \ is_signed_type(type), FILTER_OTHER); \ if (ret) \ return ret; static int trace_define_generic_fields(void) { int ret; __generic_field(int, CPU, FILTER_CPU); __generic_field(int, cpu, FILTER_CPU); __generic_field(char *, COMM, FILTER_COMM); __generic_field(char *, comm, FILTER_COMM); return ret; } static int trace_define_common_fields(void) { int ret; struct trace_entry ent; __common_field(unsigned short, type); __common_field(unsigned char, flags); __common_field(unsigned char, preempt_count); __common_field(int, pid); return ret; } static void trace_destroy_fields(struct trace_event_call *call) { struct ftrace_event_field *field, *next; struct list_head *head; head = trace_get_fields(call); list_for_each_entry_safe(field, next, head, link) { list_del(&field->link); kmem_cache_free(field_cachep, field); } } /* * run-time version of trace_event_get_offsets_<call>() that returns the last * accessible offset of trace fields excluding __dynamic_array bytes */ int trace_event_get_offsets(struct trace_event_call *call) { struct ftrace_event_field *tail; struct list_head *head; head = trace_get_fields(call); /* * head->next points to the last field with the largest offset, * since it was added last by trace_define_field() */ tail = list_first_entry(head, struct ftrace_event_field, link); return tail->offset + tail->size; } int trace_event_raw_init(struct trace_event_call *call) { int id; id = register_trace_event(&call->event); if (!id) return -ENODEV; return 0; } EXPORT_SYMBOL_GPL(trace_event_raw_init); bool trace_event_ignore_this_pid(struct trace_event_file *trace_file) { struct trace_array *tr = trace_file->tr; struct trace_array_cpu *data; struct trace_pid_list *no_pid_list; struct trace_pid_list *pid_list; pid_list = rcu_dereference_raw(tr->filtered_pids); no_pid_list = rcu_dereference_raw(tr->filtered_no_pids); if (!pid_list && !no_pid_list) return false; data = this_cpu_ptr(tr->array_buffer.data); return data->ignore_pid; } EXPORT_SYMBOL_GPL(trace_event_ignore_this_pid); void *trace_event_buffer_reserve(struct trace_event_buffer *fbuffer, struct trace_event_file *trace_file, unsigned long len) { struct trace_event_call *event_call = trace_file->event_call; if ((trace_file->flags & EVENT_FILE_FL_PID_FILTER) && trace_event_ignore_this_pid(trace_file)) return NULL; local_save_flags(fbuffer->flags); fbuffer->pc = preempt_count(); /* * If CONFIG_PREEMPTION is enabled, then the tracepoint itself disables * preemption (adding one to the preempt_count). Since we are * interested in the preempt_count at the time the tracepoint was * hit, we need to subtract one to offset the increment. */ if (IS_ENABLED(CONFIG_PREEMPTION)) fbuffer->pc--; fbuffer->trace_file = trace_file; fbuffer->event = trace_event_buffer_lock_reserve(&fbuffer->buffer, trace_file, event_call->event.type, len, fbuffer->flags, fbuffer->pc); if (!fbuffer->event) return NULL; fbuffer->regs = NULL; fbuffer->entry = ring_buffer_event_data(fbuffer->event); return fbuffer->entry; } EXPORT_SYMBOL_GPL(trace_event_buffer_reserve); int trace_event_reg(struct trace_event_call *call, enum trace_reg type, void *data) { struct trace_event_file *file = data; WARN_ON(!(call->flags & TRACE_EVENT_FL_TRACEPOINT)); switch (type) { case TRACE_REG_REGISTER: return tracepoint_probe_register(call->tp, call->class->probe, file); case TRACE_REG_UNREGISTER: tracepoint_probe_unregister(call->tp, call->class->probe, file); return 0; #ifdef CONFIG_PERF_EVENTS case TRACE_REG_PERF_REGISTER: return tracepoint_probe_register(call->tp, call->class->perf_probe, call); case TRACE_REG_PERF_UNREGISTER: tracepoint_probe_unregister(call->tp, call->class->perf_probe, call); return 0; case TRACE_REG_PERF_OPEN: case TRACE_REG_PERF_CLOSE: case TRACE_REG_PERF_ADD: case TRACE_REG_PERF_DEL: return 0; #endif } return 0; } EXPORT_SYMBOL_GPL(trace_event_reg); void trace_event_enable_cmd_record(bool enable) { struct trace_event_file *file; struct trace_array *tr; lockdep_assert_held(&event_mutex); do_for_each_event_file(tr, file) { if (!(file->flags & EVENT_FILE_FL_ENABLED)) continue; if (enable) { tracing_start_cmdline_record(); set_bit(EVENT_FILE_FL_RECORDED_CMD_BIT, &file->flags); } else { tracing_stop_cmdline_record(); clear_bit(EVENT_FILE_FL_RECORDED_CMD_BIT, &file->flags); } } while_for_each_event_file(); } void trace_event_enable_tgid_record(bool enable) { struct trace_event_file *file; struct trace_array *tr; lockdep_assert_held(&event_mutex); do_for_each_event_file(tr, file) { if (!(file->flags & EVENT_FILE_FL_ENABLED)) continue; if (enable) { tracing_start_tgid_record(); set_bit(EVENT_FILE_FL_RECORDED_TGID_BIT, &file->flags); } else { tracing_stop_tgid_record(); clear_bit(EVENT_FILE_FL_RECORDED_TGID_BIT, &file->flags); } } while_for_each_event_file(); } static int __ftrace_event_enable_disable(struct trace_event_file *file, int enable, int soft_disable) { struct trace_event_call *call = file->event_call; struct trace_array *tr = file->tr; unsigned long file_flags = file->flags; int ret = 0; int disable; switch (enable) { case 0: /* * When soft_disable is set and enable is cleared, the sm_ref * reference counter is decremented. If it reaches 0, we want * to clear the SOFT_DISABLED flag but leave the event in the * state that it was. That is, if the event was enabled and * SOFT_DISABLED isn't set, then do nothing. But if SOFT_DISABLED * is set we do not want the event to be enabled before we * clear the bit. * * When soft_disable is not set but the SOFT_MODE flag is, * we do nothing. Do not disable the tracepoint, otherwise * "soft enable"s (clearing the SOFT_DISABLED bit) wont work. */ if (soft_disable) { if (atomic_dec_return(&file->sm_ref) > 0) break; disable = file->flags & EVENT_FILE_FL_SOFT_DISABLED; clear_bit(EVENT_FILE_FL_SOFT_MODE_BIT, &file->flags); } else disable = !(file->flags & EVENT_FILE_FL_SOFT_MODE); if (disable && (file->flags & EVENT_FILE_FL_ENABLED)) { clear_bit(EVENT_FILE_FL_ENABLED_BIT, &file->flags); if (file->flags & EVENT_FILE_FL_RECORDED_CMD) { tracing_stop_cmdline_record(); clear_bit(EVENT_FILE_FL_RECORDED_CMD_BIT, &file->flags); } if (file->flags & EVENT_FILE_FL_RECORDED_TGID) { tracing_stop_tgid_record(); clear_bit(EVENT_FILE_FL_RECORDED_TGID_BIT, &file->flags); } call->class->reg(call, TRACE_REG_UNREGISTER, file); } /* If in SOFT_MODE, just set the SOFT_DISABLE_BIT, else clear it */ if (file->flags & EVENT_FILE_FL_SOFT_MODE) set_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags); else clear_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags); break; case 1: /* * When soft_disable is set and enable is set, we want to * register the tracepoint for the event, but leave the event * as is. That means, if the event was already enabled, we do * nothing (but set SOFT_MODE). If the event is disabled, we * set SOFT_DISABLED before enabling the event tracepoint, so * it still seems to be disabled. */ if (!soft_disable) clear_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags); else { if (atomic_inc_return(&file->sm_ref) > 1) break; set_bit(EVENT_FILE_FL_SOFT_MODE_BIT, &file->flags); } if (!(file->flags & EVENT_FILE_FL_ENABLED)) { bool cmd = false, tgid = false; /* Keep the event disabled, when going to SOFT_MODE. */ if (soft_disable) set_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags); if (tr->trace_flags & TRACE_ITER_RECORD_CMD) { cmd = true; tracing_start_cmdline_record(); set_bit(EVENT_FILE_FL_RECORDED_CMD_BIT, &file->flags); } if (tr->trace_flags & TRACE_ITER_RECORD_TGID) { tgid = true; tracing_start_tgid_record(); set_bit(EVENT_FILE_FL_RECORDED_TGID_BIT, &file->flags); } ret = call->class->reg(call, TRACE_REG_REGISTER, file); if (ret) { if (cmd) tracing_stop_cmdline_record(); if (tgid) tracing_stop_tgid_record(); pr_info("event trace: Could not enable event " "%s\n", trace_event_name(call)); break; } set_bit(EVENT_FILE_FL_ENABLED_BIT, &file->flags); /* WAS_ENABLED gets set but never cleared. */ set_bit(EVENT_FILE_FL_WAS_ENABLED_BIT, &file->flags); } break; } /* Enable or disable use of trace_buffered_event */ if ((file_flags & EVENT_FILE_FL_SOFT_DISABLED) != (file->flags & EVENT_FILE_FL_SOFT_DISABLED)) { if (file->flags & EVENT_FILE_FL_SOFT_DISABLED) trace_buffered_event_enable(); else trace_buffered_event_disable(); } return ret; } int trace_event_enable_disable(struct trace_event_file *file, int enable, int soft_disable) { return __ftrace_event_enable_disable(file, enable, soft_disable); } static int ftrace_event_enable_disable(struct trace_event_file *file, int enable) { return __ftrace_event_enable_disable(file, enable, 0); } static void ftrace_clear_events(struct trace_array *tr) { struct trace_event_file *file; mutex_lock(&event_mutex); list_for_each_entry(file, &tr->events, list) { ftrace_event_enable_disable(file, 0); } mutex_unlock(&event_mutex); } static void event_filter_pid_sched_process_exit(void *data, struct task_struct *task) { struct trace_pid_list *pid_list; struct trace_array *tr = data; pid_list = rcu_dereference_raw(tr->filtered_pids); trace_filter_add_remove_task(pid_list, NULL, task); pid_list = rcu_dereference_raw(tr->filtered_no_pids); trace_filter_add_remove_task(pid_list, NULL, task); } static void event_filter_pid_sched_process_fork(void *data, struct task_struct *self, struct task_struct *task) { struct trace_pid_list *pid_list; struct trace_array *tr = data; pid_list = rcu_dereference_sched(tr->filtered_pids); trace_filter_add_remove_task(pid_list, self, task); pid_list = rcu_dereference_sched(tr->filtered_no_pids); trace_filter_add_remove_task(pid_list, self, task); } void trace_event_follow_fork(struct trace_array *tr, bool enable) { if (enable) { register_trace_prio_sched_process_fork(event_filter_pid_sched_process_fork, tr, INT_MIN); register_trace_prio_sched_process_free(event_filter_pid_sched_process_exit, tr, INT_MAX); } else { unregister_trace_sched_process_fork(event_filter_pid_sched_process_fork, tr); unregister_trace_sched_process_free(event_filter_pid_sched_process_exit, tr); } } static void event_filter_pid_sched_switch_probe_pre(void *data, bool preempt, struct task_struct *prev, struct task_struct *next) { struct trace_array *tr = data; struct trace_pid_list *no_pid_list; struct trace_pid_list *pid_list; bool ret; pid_list = rcu_dereference_sched(tr->filtered_pids); no_pid_list = rcu_dereference_sched(tr->filtered_no_pids); /* * Sched switch is funny, as we only want to ignore it * in the notrace case if both prev and next should be ignored. */ ret = trace_ignore_this_task(NULL, no_pid_list, prev) && trace_ignore_this_task(NULL, no_pid_list, next); this_cpu_write(tr->array_buffer.data->ignore_pid, ret || (trace_ignore_this_task(pid_list, NULL, prev) && trace_ignore_this_task(pid_list, NULL, next))); } static void event_filter_pid_sched_switch_probe_post(void *data, bool preempt, struct task_struct *prev, struct task_struct *next) { struct trace_array *tr = data; struct trace_pid_list *no_pid_list; struct trace_pid_list *pid_list; pid_list = rcu_dereference_sched(tr->filtered_pids); no_pid_list = rcu_dereference_sched(tr->filtered_no_pids); this_cpu_write(tr->array_buffer.data->ignore_pid, trace_ignore_this_task(pid_list, no_pid_list, next)); } static void event_filter_pid_sched_wakeup_probe_pre(void *data, struct task_struct *task) { struct trace_array *tr = data; struct trace_pid_list *no_pid_list; struct trace_pid_list *pid_list; /* Nothing to do if we are already tracing */ if (!this_cpu_read(tr->array_buffer.data->ignore_pid)) return; pid_list = rcu_dereference_sched(tr->filtered_pids); no_pid_list = rcu_dereference_sched(tr->filtered_no_pids); this_cpu_write(tr->array_buffer.data->ignore_pid, trace_ignore_this_task(pid_list, no_pid_list, task)); } static void event_filter_pid_sched_wakeup_probe_post(void *data, struct task_struct *task) { struct trace_array *tr = data; struct trace_pid_list *no_pid_list; struct trace_pid_list *pid_list; /* Nothing to do if we are not tracing */ if (this_cpu_read(tr->array_buffer.data->ignore_pid)) return; pid_list = rcu_dereference_sched(tr->filtered_pids); no_pid_list = rcu_dereference_sched(tr->filtered_no_pids); /* Set tracing if current is enabled */ this_cpu_write(tr->array_buffer.data->ignore_pid, trace_ignore_this_task(pid_list, no_pid_list, current)); } static void unregister_pid_events(struct trace_array *tr) { unregister_trace_sched_switch(event_filter_pid_sched_switch_probe_pre, tr); unregister_trace_sched_switch(event_filter_pid_sched_switch_probe_post, tr); unregister_trace_sched_wakeup(event_filter_pid_sched_wakeup_probe_pre, tr); unregister_trace_sched_wakeup(event_filter_pid_sched_wakeup_probe_post, tr); unregister_trace_sched_wakeup_new(event_filter_pid_sched_wakeup_probe_pre, tr); unregister_trace_sched_wakeup_new(event_filter_pid_sched_wakeup_probe_post, tr); unregister_trace_sched_waking(event_filter_pid_sched_wakeup_probe_pre, tr); unregister_trace_sched_waking(event_filter_pid_sched_wakeup_probe_post, tr); } static void __ftrace_clear_event_pids(struct trace_array *tr, int type) { struct trace_pid_list *pid_list; struct trace_pid_list *no_pid_list; struct trace_event_file *file; int cpu; pid_list = rcu_dereference_protected(tr->filtered_pids, lockdep_is_held(&event_mutex)); no_pid_list = rcu_dereference_protected(tr->filtered_no_pids, lockdep_is_held(&event_mutex)); /* Make sure there's something to do */ if (!pid_type_enabled(type, pid_list, no_pid_list)) return; if (!still_need_pid_events(type, pid_list, no_pid_list)) { unregister_pid_events(tr); list_for_each_entry(file, &tr->events, list) { clear_bit(EVENT_FILE_FL_PID_FILTER_BIT, &file->flags); } for_each_possible_cpu(cpu) per_cpu_ptr(tr->array_buffer.data, cpu)->ignore_pid = false; } if (type & TRACE_PIDS) rcu_assign_pointer(tr->filtered_pids, NULL); if (type & TRACE_NO_PIDS) rcu_assign_pointer(tr->filtered_no_pids, NULL); /* Wait till all users are no longer using pid filtering */ tracepoint_synchronize_unregister(); if ((type & TRACE_PIDS) && pid_list) trace_free_pid_list(pid_list); if ((type & TRACE_NO_PIDS) && no_pid_list) trace_free_pid_list(no_pid_list); } static void ftrace_clear_event_pids(struct trace_array *tr, int type) { mutex_lock(&event_mutex); __ftrace_clear_event_pids(tr, type); mutex_unlock(&event_mutex); } static void __put_system(struct event_subsystem *system) { struct event_filter *filter = system->filter; WARN_ON_ONCE(system_refcount(system) == 0); if (system_refcount_dec(system)) return; list_del(&system->list); if (filter) { kfree(filter->filter_string); kfree(filter); } kfree_const(system->name); kfree(system); } static void __get_system(struct event_subsystem *system) { WARN_ON_ONCE(system_refcount(system) == 0); system_refcount_inc(system); } static void __get_system_dir(struct trace_subsystem_dir *dir) { WARN_ON_ONCE(dir->ref_count == 0); dir->ref_count++; __get_system(dir->subsystem); } static void __put_system_dir(struct trace_subsystem_dir *dir) { WARN_ON_ONCE(dir->ref_count == 0); /* If the subsystem is about to be freed, the dir must be too */ WARN_ON_ONCE(system_refcount(dir->subsystem) == 1 && dir->ref_count != 1); __put_system(dir->subsystem); if (!--dir->ref_count) kfree(dir); } static void put_system(struct trace_subsystem_dir *dir) { mutex_lock(&event_mutex); __put_system_dir(dir); mutex_unlock(&event_mutex); } static void remove_subsystem(struct trace_subsystem_dir *dir) { if (!dir) return; if (!--dir->nr_events) { tracefs_remove(dir->entry); list_del(&dir->list); __put_system_dir(dir); } } static void remove_event_file_dir(struct trace_event_file *file) { struct dentry *dir = file->dir; struct dentry *child; if (dir) { spin_lock(&dir->d_lock); /* probably unneeded */ list_for_each_entry(child, &dir->d_subdirs, d_child) { if (d_really_is_positive(child)) /* probably unneeded */ d_inode(child)->i_private = NULL; } spin_unlock(&dir->d_lock); tracefs_remove(dir); } list_del(&file->list); remove_subsystem(file->system); free_event_filter(file->filter); kmem_cache_free(file_cachep, file); } /* * __ftrace_set_clr_event(NULL, NULL, NULL, set) will set/unset all events. */ static int __ftrace_set_clr_event_nolock(struct trace_array *tr, const char *match, const char *sub, const char *event, int set) { struct trace_event_file *file; struct trace_event_call *call; const char *name; int ret = -EINVAL; int eret = 0; list_for_each_entry(file, &tr->events, list) { call = file->event_call; name = trace_event_name(call); if (!name || !call->class || !call->class->reg) continue; if (call->flags & TRACE_EVENT_FL_IGNORE_ENABLE) continue; if (match && strcmp(match, name) != 0 && strcmp(match, call->class->system) != 0) continue; if (sub && strcmp(sub, call->class->system) != 0) continue; if (event && strcmp(event, name) != 0) continue; ret = ftrace_event_enable_disable(file, set); /* * Save the first error and return that. Some events * may still have been enabled, but let the user * know that something went wrong. */ if (ret && !eret) eret = ret; ret = eret; } return ret; } static int __ftrace_set_clr_event(struct trace_array *tr, const char *match, const char *sub, const char *event, int set) { int ret; mutex_lock(&event_mutex); ret = __ftrace_set_clr_event_nolock(tr, match, sub, event, set); mutex_unlock(&event_mutex); return ret; } int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set) { char *event = NULL, *sub = NULL, *match; int ret; if (!tr) return -ENOENT; /* * The buf format can be <subsystem>:<event-name> * *:<event-name> means any event by that name. * :<event-name> is the same. * * <subsystem>:* means all events in that subsystem * <subsystem>: means the same. * * <name> (no ':') means all events in a subsystem with * the name <name> or any event that matches <name> */ match = strsep(&buf, ":"); if (buf) { sub = match; event = buf; match = NULL; if (!strlen(sub) || strcmp(sub, "*") == 0) sub = NULL; if (!strlen(event) || strcmp(event, "*") == 0) event = NULL; } ret = __ftrace_set_clr_event(tr, match, sub, event, set); /* Put back the colon to allow this to be called again */ if (buf) *(buf - 1) = ':'; return ret; } /** * trace_set_clr_event - enable or disable an event * @system: system name to match (NULL for any system) * @event: event name to match (NULL for all events, within system) * @set: 1 to enable, 0 to disable * * This is a way for other parts of the kernel to enable or disable * event recording. * * Returns 0 on success, -EINVAL if the parameters do not match any * registered events. */ int trace_set_clr_event(const char *system, const char *event, int set) { struct trace_array *tr = top_trace_array(); if (!tr) return -ENODEV; return __ftrace_set_clr_event(tr, NULL, system, event, set); } EXPORT_SYMBOL_GPL(trace_set_clr_event); /** * trace_array_set_clr_event - enable or disable an event for a trace array. * @tr: concerned trace array. * @system: system name to match (NULL for any system) * @event: event name to match (NULL for all events, within system) * @enable: true to enable, false to disable * * This is a way for other parts of the kernel to enable or disable * event recording. * * Returns 0 on success, -EINVAL if the parameters do not match any * registered events. */ int trace_array_set_clr_event(struct trace_array *tr, const char *system, const char *event, bool enable) { int set; if (!tr) return -ENOENT; set = (enable == true) ? 1 : 0; return __ftrace_set_clr_event(tr, NULL, system, event, set); } EXPORT_SYMBOL_GPL(trace_array_set_clr_event); /* 128 should be much more than enough */ #define EVENT_BUF_SIZE 127 static ssize_t ftrace_event_write(struct file *file, const char __user *ubuf, size_t cnt, loff_t *ppos) { struct trace_parser parser; struct seq_file *m = file->private_data; struct trace_array *tr = m->private; ssize_t read, ret; if (!cnt) return 0; ret = tracing_update_buffers(); if (ret < 0) return ret; if (trace_parser_get_init(&parser, EVENT_BUF_SIZE + 1)) return -ENOMEM; read = trace_get_user(&parser, ubuf, cnt, ppos); if (read >= 0 && trace_parser_loaded((&parser))) { int set = 1; if (*parser.buffer == '!') set = 0; ret = ftrace_set_clr_event(tr, parser.buffer + !set, set); if (ret) goto out_put; } ret = read; out_put: trace_parser_put(&parser); return ret; } static void * t_next(struct seq_file *m, void *v, loff_t *pos) { struct trace_event_file *file = v; struct trace_event_call *call; struct trace_array *tr = m->private; (*pos)++; list_for_each_entry_continue(file, &tr->events, list) { call = file->event_call; /* * The ftrace subsystem is for showing formats only. * They can not be enabled or disabled via the event files. */ if (call->class && call->class->reg && !(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)) return file; } return NULL; } static void *t_start(struct seq_file *m, loff_t *pos) { struct trace_event_file *file; struct trace_array *tr = m->private; loff_t l; mutex_lock(&event_mutex); file = list_entry(&tr->events, struct trace_event_file, list); for (l = 0; l <= *pos; ) { file = t_next(m, file, &l); if (!file) break; } return file; } static void * s_next(struct seq_file *m, void *v, loff_t *pos) { struct trace_event_file *file = v; struct trace_array *tr = m->private; (*pos)++; list_for_each_entry_continue(file, &tr->events, list) { if (file->flags & EVENT_FILE_FL_ENABLED) return file; } return NULL; } static void *s_start(struct seq_file *m, loff_t *pos) { struct trace_event_file *file; struct trace_array *tr = m->private; loff_t l; mutex_lock(&event_mutex); file = list_entry(&tr->events, struct trace_event_file, list); for (l = 0; l <= *pos; ) { file = s_next(m, file, &l); if (!file) break; } return file; } static int t_show(struct seq_file *m, void *v) { struct trace_event_file *file = v; struct trace_event_call *call = file->event_call; if (strcmp(call->class->system, TRACE_SYSTEM) != 0) seq_printf(m, "%s:", call->class->system); seq_printf(m, "%s\n", trace_event_name(call)); return 0; } static void t_stop(struct seq_file *m, void *p) { mutex_unlock(&event_mutex); } static void * __next(struct seq_file *m, void *v, loff_t *pos, int type) { struct trace_array *tr = m->private; struct trace_pid_list *pid_list; if (type == TRACE_PIDS) pid_list = rcu_dereference_sched(tr->filtered_pids); else pid_list = rcu_dereference_sched(tr->filtered_no_pids); return trace_pid_next(pid_list, v, pos); } static void * p_next(struct seq_file *m, void *v, loff_t *pos) { return __next(m, v, pos, TRACE_PIDS); } static void * np_next(struct seq_file *m, void *v, loff_t *pos) { return __next(m, v, pos, TRACE_NO_PIDS); } static void *__start(struct seq_file *m, loff_t *pos, int type) __acquires(RCU) { struct trace_pid_list *pid_list; struct trace_array *tr = m->private; /* * Grab the mutex, to keep calls to p_next() having the same * tr->filtered_pids as p_start() has. * If we just passed the tr->filtered_pids around, then RCU would * have been enough, but doing that makes things more complex. */ mutex_lock(&event_mutex); rcu_read_lock_sched(); if (type == TRACE_PIDS) pid_list = rcu_dereference_sched(tr->filtered_pids); else pid_list = rcu_dereference_sched(tr->filtered_no_pids); if (!pid_list) return NULL; return trace_pid_start(pid_list, pos); } static void *p_start(struct seq_file *m, loff_t *pos) __acquires(RCU) { return __start(m, pos, TRACE_PIDS); } static void *np_start(struct seq_file *m, loff_t *pos) __acquires(RCU) { return __start(m, pos, TRACE_NO_PIDS); } static void p_stop(struct seq_file *m, void *p) __releases(RCU) { rcu_read_unlock_sched(); mutex_unlock(&event_mutex); } static ssize_t event_enable_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { struct trace_event_file *file; unsigned long flags; char buf[4] = "0"; mutex_lock(&event_mutex); file = event_file_data(filp); if (likely(file)) flags = file->flags; mutex_unlock(&event_mutex); if (!file) return -ENODEV; if (flags & EVENT_FILE_FL_ENABLED && !(flags & EVENT_FILE_FL_SOFT_DISABLED)) strcpy(buf, "1"); if (flags & EVENT_FILE_FL_SOFT_DISABLED || flags & EVENT_FILE_FL_SOFT_MODE) strcat(buf, "*"); strcat(buf, "\n"); return simple_read_from_buffer(ubuf, cnt, ppos, buf, strlen(buf)); } static ssize_t event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { struct trace_event_file *file; unsigned long val; int ret; ret = kstrtoul_from_user(ubuf, cnt, 10, &val); if (ret) return ret; ret = tracing_update_buffers(); if (ret < 0) return ret; switch (val) { case 0: case 1: ret = -ENODEV; mutex_lock(&event_mutex); file = event_file_data(filp); if (likely(file)) ret = ftrace_event_enable_disable(file, val); mutex_unlock(&event_mutex); break; default: return -EINVAL; } *ppos += cnt; return ret ? ret : cnt; } static ssize_t system_enable_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { const char set_to_char[4] = { '?', '0', '1', 'X' }; struct trace_subsystem_dir *dir = filp->private_data; struct event_subsystem *system = dir->subsystem; struct trace_event_call *call; struct trace_event_file *file; struct trace_array *tr = dir->tr; char buf[2]; int set = 0; int ret; mutex_lock(&event_mutex); list_for_each_entry(file, &tr->events, list) { call = file->event_call; if ((call->flags & TRACE_EVENT_FL_IGNORE_ENABLE) || !trace_event_name(call) || !call->class || !call->class->reg) continue; if (system && strcmp(call->class->system, system->name) != 0) continue; /* * We need to find out if all the events are set * or if all events or cleared, or if we have * a mixture. */ set |= (1 << !!(file->flags & EVENT_FILE_FL_ENABLED)); /* * If we have a mixture, no need to look further. */ if (set == 3) break; } mutex_unlock(&event_mutex); buf[0] = set_to_char[set]; buf[1] = '\n'; ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); return ret; } static ssize_t system_enable_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { struct trace_subsystem_dir *dir = filp->private_data; struct event_subsystem *system = dir->subsystem; const char *name = NULL; unsigned long val; ssize_t ret; ret = kstrtoul_from_user(ubuf, cnt, 10, &val); if (ret) return ret; ret = tracing_update_buffers(); if (ret < 0) return ret; if (val != 0 && val != 1) return -EINVAL; /* * Opening of "enable" adds a ref count to system, * so the name is safe to use. */ if (system) name = system->name; ret = __ftrace_set_clr_event(dir->tr, NULL, name, NULL, val); if (ret) goto out; ret = cnt; out: *ppos += cnt; return ret; } enum { FORMAT_HEADER = 1, FORMAT_FIELD_SEPERATOR = 2, FORMAT_PRINTFMT = 3, }; static void *f_next(struct seq_file *m, void *v, loff_t *pos) { struct trace_event_call *call = event_file_data(m->private); struct list_head *common_head = &ftrace_common_fields; struct list_head *head = trace_get_fields(call); struct list_head *node = v; (*pos)++; switch ((unsigned long)v) { case FORMAT_HEADER: node = common_head; break; case FORMAT_FIELD_SEPERATOR: node = head; break; case FORMAT_PRINTFMT: /* all done */ return NULL; } node = node->prev; if (node == common_head) return (void *)FORMAT_FIELD_SEPERATOR; else if (node == head) return (void *)FORMAT_PRINTFMT; else return node; } static int f_show(struct seq_file *m, void *v) { struct trace_event_call *call = event_file_data(m->private); struct ftrace_event_field *field; const char *array_descriptor; switch ((unsigned long)v) { case FORMAT_HEADER: seq_printf(m, "name: %s\n", trace_event_name(call)); seq_printf(m, "ID: %d\n", call->event.type); seq_puts(m, "format:\n"); return 0; case FORMAT_FIELD_SEPERATOR: seq_putc(m, '\n'); return 0; case FORMAT_PRINTFMT: seq_printf(m, "\nprint fmt: %s\n", call->print_fmt); return 0; } field = list_entry(v, struct ftrace_event_field, link); /* * Smartly shows the array type(except dynamic array). * Normal: * field:TYPE VAR * If TYPE := TYPE[LEN], it is shown: * field:TYPE VAR[LEN] */ array_descriptor = strchr(field->type, '['); if (str_has_prefix(field->type, "__data_loc")) array_descriptor = NULL; if (!array_descriptor) seq_printf(m, "\tfield:%s %s;\toffset:%u;\tsize:%u;\tsigned:%d;\n", field->type, field->name, field->offset, field->size, !!field->is_signed); else seq_printf(m, "\tfield:%.*s %s%s;\toffset:%u;\tsize:%u;\tsigned:%d;\n", (int)(array_descriptor - field->type), field->type, field->name, array_descriptor, field->offset, field->size, !!field->is_signed); return 0; } static void *f_start(struct seq_file *m, loff_t *pos) { void *p = (void *)FORMAT_HEADER; loff_t l = 0; /* ->stop() is called even if ->start() fails */ mutex_lock(&event_mutex); if (!event_file_data(m->private)) return ERR_PTR(-ENODEV); while (l < *pos && p) p = f_next(m, p, &l); return p; } static void f_stop(struct seq_file *m, void *p) { mutex_unlock(&event_mutex); } static const struct seq_operations trace_format_seq_ops = { .start = f_start, .next = f_next, .stop = f_stop, .show = f_show, }; static int trace_format_open(struct inode *inode, struct file *file) { struct seq_file *m; int ret; /* Do we want to hide event format files on tracefs lockdown? */ ret = seq_open(file, &trace_format_seq_ops); if (ret < 0) return ret; m = file->private_data; m->private = file; return 0; } static ssize_t event_id_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { int id = (long)event_file_data(filp); char buf[32]; int len; if (unlikely(!id)) return -ENODEV; len = sprintf(buf, "%d\n", id); return simple_read_from_buffer(ubuf, cnt, ppos, buf, len); } static ssize_t event_filter_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { struct trace_event_file *file; struct trace_seq *s; int r = -ENODEV; if (*ppos) return 0; s = kmalloc(sizeof(*s), GFP_KERNEL); if (!s) return -ENOMEM; trace_seq_init(s); mutex_lock(&event_mutex); file = event_file_data(filp); if (file) print_event_filter(file, s); mutex_unlock(&event_mutex); if (file) r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, trace_seq_used(s)); kfree(s); return r; } static ssize_t event_filter_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { struct trace_event_file *file; char *buf; int err = -ENODEV; if (cnt >= PAGE_SIZE) return -EINVAL; buf = memdup_user_nul(ubuf, cnt); if (IS_ERR(buf)) return PTR_ERR(buf); mutex_lock(&event_mutex); file = event_file_data(filp); if (file) err = apply_event_filter(file, buf); mutex_unlock(&event_mutex); kfree(buf); if (err < 0) return err; *ppos += cnt; return cnt; } static LIST_HEAD(event_subsystems); static int subsystem_open(struct inode *inode, struct file *filp) { struct event_subsystem *system = NULL; struct trace_subsystem_dir *dir = NULL; /* Initialize for gcc */ struct trace_array *tr; int ret; if (tracing_is_disabled()) return -ENODEV; /* Make sure the system still exists */ mutex_lock(&event_mutex); mutex_lock(&trace_types_lock); list_for_each_entry(tr, &ftrace_trace_arrays, list) { list_for_each_entry(dir, &tr->systems, list) { if (dir == inode->i_private) { /* Don't open systems with no events */ if (dir->nr_events) { __get_system_dir(dir); system = dir->subsystem; } goto exit_loop; } } } exit_loop: mutex_unlock(&trace_types_lock); mutex_unlock(&event_mutex); if (!system) return -ENODEV; /* Some versions of gcc think dir can be uninitialized here */ WARN_ON(!dir); /* Still need to increment the ref count of the system */ if (trace_array_get(tr) < 0) { put_system(dir); return -ENODEV; } ret = tracing_open_generic(inode, filp); if (ret < 0) { trace_array_put(tr); put_system(dir); } return ret; } static int system_tr_open(struct inode *inode, struct file *filp) { struct trace_subsystem_dir *dir; struct trace_array *tr = inode->i_private; int ret; /* Make a temporary dir that has no system but points to tr */ dir = kzalloc(sizeof(*dir), GFP_KERNEL); if (!dir) return -ENOMEM; ret = tracing_open_generic_tr(inode, filp); if (ret < 0) { kfree(dir); return ret; } dir->tr = tr; filp->private_data = dir; return 0; } static int subsystem_release(struct inode *inode, struct file *file) { struct trace_subsystem_dir *dir = file->private_data; trace_array_put(dir->tr); /* * If dir->subsystem is NULL, then this is a temporary * descriptor that was made for a trace_array to enable * all subsystems. */ if (dir->subsystem) put_system(dir); else kfree(dir); return 0; } static ssize_t subsystem_filter_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { struct trace_subsystem_dir *dir = filp->private_data; struct event_subsystem *system = dir->subsystem; struct trace_seq *s; int r; if (*ppos) return 0; s = kmalloc(sizeof(*s), GFP_KERNEL); if (!s) return -ENOMEM; trace_seq_init(s); print_subsystem_event_filter(system, s); r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, trace_seq_used(s)); kfree(s); return r; } static ssize_t subsystem_filter_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { struct trace_subsystem_dir *dir = filp->private_data; char *buf; int err; if (cnt >= PAGE_SIZE) return -EINVAL; buf = memdup_user_nul(ubuf, cnt); if (IS_ERR(buf)) return PTR_ERR(buf); err = apply_subsystem_event_filter(dir, buf); kfree(buf); if (err < 0) return err; *ppos += cnt; return cnt; } static ssize_t show_header(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { int (*func)(struct trace_seq *s) = filp->private_data; struct trace_seq *s; int r; if (*ppos) return 0; s = kmalloc(sizeof(*s), GFP_KERNEL); if (!s) return -ENOMEM; trace_seq_init(s); func(s); r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, trace_seq_used(s)); kfree(s); return r; } static void ignore_task_cpu(void *data) { struct trace_array *tr = data; struct trace_pid_list *pid_list; struct trace_pid_list *no_pid_list; /* * This function is called by on_each_cpu() while the * event_mutex is held. */ pid_list = rcu_dereference_protected(tr->filtered_pids, mutex_is_locked(&event_mutex)); no_pid_list = rcu_dereference_protected(tr->filtered_no_pids, mutex_is_locked(&event_mutex)); this_cpu_write(tr->array_buffer.data->ignore_pid, trace_ignore_this_task(pid_list, no_pid_list, current)); } static void register_pid_events(struct trace_array *tr) { /* * Register a probe that is called before all other probes * to set ignore_pid if next or prev do not match. * Register a probe this is called after all other probes * to only keep ignore_pid set if next pid matches. */ register_trace_prio_sched_switch(event_filter_pid_sched_switch_probe_pre, tr, INT_MAX); register_trace_prio_sched_switch(event_filter_pid_sched_switch_probe_post, tr, 0); register_trace_prio_sched_wakeup(event_filter_pid_sched_wakeup_probe_pre, tr, INT_MAX); register_trace_prio_sched_wakeup(event_filter_pid_sched_wakeup_probe_post, tr, 0); register_trace_prio_sched_wakeup_new(event_filter_pid_sched_wakeup_probe_pre, tr, INT_MAX); register_trace_prio_sched_wakeup_new(event_filter_pid_sched_wakeup_probe_post, tr, 0); register_trace_prio_sched_waking(event_filter_pid_sched_wakeup_probe_pre, tr, INT_MAX); register_trace_prio_sched_waking(event_filter_pid_sched_wakeup_probe_post, tr, 0); } static ssize_t event_pid_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos, int type) { struct seq_file *m = filp->private_data; struct trace_array *tr = m->private; struct trace_pid_list *filtered_pids = NULL; struct trace_pid_list *other_pids = NULL; struct trace_pid_list *pid_list; struct trace_event_file *file; ssize_t ret; if (!cnt) return 0; ret = tracing_update_buffers(); if (ret < 0) return ret; mutex_lock(&event_mutex); if (type == TRACE_PIDS) { filtered_pids = rcu_dereference_protected(tr->filtered_pids, lockdep_is_held(&event_mutex)); other_pids = rcu_dereference_protected(tr->filtered_no_pids, lockdep_is_held(&event_mutex)); } else { filtered_pids = rcu_dereference_protected(tr->filtered_no_pids, lockdep_is_held(&event_mutex)); other_pids = rcu_dereference_protected(tr->filtered_pids, lockdep_is_held(&event_mutex)); } ret = trace_pid_write(filtered_pids, &pid_list, ubuf, cnt); if (ret < 0) goto out; if (type == TRACE_PIDS) rcu_assign_pointer(tr->filtered_pids, pid_list); else rcu_assign_pointer(tr->filtered_no_pids, pid_list); list_for_each_entry(file, &tr->events, list) { set_bit(EVENT_FILE_FL_PID_FILTER_BIT, &file->flags); } if (filtered_pids) { tracepoint_synchronize_unregister(); trace_free_pid_list(filtered_pids); } else if (pid_list && !other_pids) { register_pid_events(tr); } /* * Ignoring of pids is done at task switch. But we have to * check for those tasks that are currently running. * Always do this in case a pid was appended or removed. */ on_each_cpu(ignore_task_cpu, tr, 1); out: mutex_unlock(&event_mutex); if (ret > 0) *ppos += ret; return ret; } static ssize_t ftrace_event_pid_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { return event_pid_write(filp, ubuf, cnt, ppos, TRACE_PIDS); } static ssize_t ftrace_event_npid_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { return event_pid_write(filp, ubuf, cnt, ppos, TRACE_NO_PIDS); } static int ftrace_event_avail_open(struct inode *inode, struct file *file); static int ftrace_event_set_open(struct inode *inode, struct file *file); static int ftrace_event_set_pid_open(struct inode *inode, struct file *file); static int ftrace_event_set_npid_open(struct inode *inode, struct file *file); static int ftrace_event_release(struct inode *inode, struct file *file); static const struct seq_operations show_event_seq_ops = { .start = t_start, .next = t_next, .show = t_show, .stop = t_stop, }; static const struct seq_operations show_set_event_seq_ops = { .start = s_start, .next = s_next, .show = t_show, .stop = t_stop, }; static const struct seq_operations show_set_pid_seq_ops = { .start = p_start, .next = p_next, .show = trace_pid_show, .stop = p_stop, }; static const struct seq_operations show_set_no_pid_seq_ops = { .start = np_start, .next = np_next, .show = trace_pid_show, .stop = p_stop, }; static const struct file_operations ftrace_avail_fops = { .open = ftrace_event_avail_open, .read = seq_read, .llseek = seq_lseek, .release = seq_release, }; static const struct file_operations ftrace_set_event_fops = { .open = ftrace_event_set_open, .read = seq_read, .write = ftrace_event_write, .llseek = seq_lseek, .release = ftrace_event_release, }; static const struct file_operations ftrace_set_event_pid_fops = { .open = ftrace_event_set_pid_open, .read = seq_read, .write = ftrace_event_pid_write, .llseek = seq_lseek, .release = ftrace_event_release, }; static const struct file_operations ftrace_set_event_notrace_pid_fops = { .open = ftrace_event_set_npid_open, .read = seq_read, .write = ftrace_event_npid_write, .llseek = seq_lseek, .release = ftrace_event_release, }; static const struct file_operations ftrace_enable_fops = { .open = tracing_open_generic, .read = event_enable_read, .write = event_enable_write, .llseek = default_llseek, }; static const struct file_operations ftrace_event_format_fops = { .open = trace_format_open, .read = seq_read, .llseek = seq_lseek, .release = seq_release, }; static const struct file_operations ftrace_event_id_fops = { .read = event_id_read, .llseek = default_llseek, }; static const struct file_operations ftrace_event_filter_fops = { .open = tracing_open_generic, .read = event_filter_read, .write = event_filter_write, .llseek = default_llseek, }; static const struct file_operations ftrace_subsystem_filter_fops = { .open = subsystem_open, .read = subsystem_filter_read, .write = subsystem_filter_write, .llseek = default_llseek, .release = subsystem_release, }; static const struct file_operations ftrace_system_enable_fops = { .open = subsystem_open, .read = system_enable_read, .write = system_enable_write, .llseek = default_llseek, .release = subsystem_release, }; static const struct file_operations ftrace_tr_enable_fops = { .open = system_tr_open, .read = system_enable_read, .write = system_enable_write, .llseek = default_llseek, .release = subsystem_release, }; static const struct file_operations ftrace_show_header_fops = { .open = tracing_open_generic, .read = show_header, .llseek = default_llseek, }; static int ftrace_event_open(struct inode *inode, struct file *file, const struct seq_operations *seq_ops) { struct seq_file *m; int ret; ret = security_locked_down(LOCKDOWN_TRACEFS); if (ret) return ret; ret = seq_open(file, seq_ops); if (ret < 0) return ret; m = file->private_data; /* copy tr over to seq ops */ m->private = inode->i_private; return ret; } static int ftrace_event_release(struct inode *inode, struct file *file) { struct trace_array *tr = inode->i_private; trace_array_put(tr); return seq_release(inode, file); } static int ftrace_event_avail_open(struct inode *inode, struct file *file) { const struct seq_operations *seq_ops = &show_event_seq_ops; /* Checks for tracefs lockdown */ return ftrace_event_open(inode, file, seq_ops); } static int ftrace_event_set_open(struct inode *inode, struct file *file) { const struct seq_operations *seq_ops = &show_set_event_seq_ops; struct trace_array *tr = inode->i_private; int ret; ret = tracing_check_open_get_tr(tr); if (ret) return ret; if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) ftrace_clear_events(tr); ret = ftrace_event_open(inode, file, seq_ops); if (ret < 0) trace_array_put(tr); return ret; } static int ftrace_event_set_pid_open(struct inode *inode, struct file *file) { const struct seq_operations *seq_ops = &show_set_pid_seq_ops; struct trace_array *tr = inode->i_private; int ret; ret = tracing_check_open_get_tr(tr); if (ret) return ret; if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) ftrace_clear_event_pids(tr, TRACE_PIDS); ret = ftrace_event_open(inode, file, seq_ops); if (ret < 0) trace_array_put(tr); return ret; } static int ftrace_event_set_npid_open(struct inode *inode, struct file *file) { const struct seq_operations *seq_ops = &show_set_no_pid_seq_ops; struct trace_array *tr = inode->i_private; int ret; ret = tracing_check_open_get_tr(tr); if (ret) return ret; if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) ftrace_clear_event_pids(tr, TRACE_NO_PIDS); ret = ftrace_event_open(inode, file, seq_ops); if (ret < 0) trace_array_put(tr); return ret; } static struct event_subsystem * create_new_subsystem(const char *name) { struct event_subsystem *system; /* need to create new entry */ system = kmalloc(sizeof(*system), GFP_KERNEL); if (!system) return NULL; system->ref_count = 1; /* Only allocate if dynamic (kprobes and modules) */ system->name = kstrdup_const(name, GFP_KERNEL); if (!system->name) goto out_free; system->filter = NULL; system->filter = kzalloc(sizeof(struct event_filter), GFP_KERNEL); if (!system->filter) goto out_free; list_add(&system->list, &event_subsystems); return system; out_free: kfree_const(system->name); kfree(system); return NULL; } static struct dentry * event_subsystem_dir(struct trace_array *tr, const char *name, struct trace_event_file *file, struct dentry *parent) { struct trace_subsystem_dir *dir; struct event_subsystem *system; struct dentry *entry; /* First see if we did not already create this dir */ list_for_each_entry(dir, &tr->systems, list) { system = dir->subsystem; if (strcmp(system->name, name) == 0) { dir->nr_events++; file->system = dir; return dir->entry; } } /* Now see if the system itself exists. */ list_for_each_entry(system, &event_subsystems, list) { if (strcmp(system->name, name) == 0) break; } /* Reset system variable when not found */ if (&system->list == &event_subsystems) system = NULL; dir = kmalloc(sizeof(*dir), GFP_KERNEL); if (!dir) goto out_fail; if (!system) { system = create_new_subsystem(name); if (!system) goto out_free; } else __get_system(system); dir->entry = tracefs_create_dir(name, parent); if (!dir->entry) { pr_warn("Failed to create system directory %s\n", name); __put_system(system); goto out_free; } dir->tr = tr; dir->ref_count = 1; dir->nr_events = 1; dir->subsystem = system; file->system = dir; entry = tracefs_create_file("filter", 0644, dir->entry, dir, &ftrace_subsystem_filter_fops); if (!entry) { kfree(system->filter); system->filter = NULL; pr_warn("Could not create tracefs '%s/filter' entry\n", name); } trace_create_file("enable", 0644, dir->entry, dir, &ftrace_system_enable_fops); list_add(&dir->list, &tr->systems); return dir->entry; out_free: kfree(dir); out_fail: /* Only print this message if failed on memory allocation */ if (!dir || !system) pr_warn("No memory to create event subsystem %s\n", name); return NULL; } static int event_define_fields(struct trace_event_call *call) { struct list_head *head; int ret = 0; /* * Other events may have the same class. Only update * the fields if they are not already defined. */ head = trace_get_fields(call); if (list_empty(head)) { struct trace_event_fields *field = call->class->fields_array; unsigned int offset = sizeof(struct trace_entry); for (; field->type; field++) { if (field->type == TRACE_FUNCTION_TYPE) { field->define_fields(call); break; } offset = ALIGN(offset, field->align); ret = trace_define_field(call, field->type, field->name, offset, field->size, field->is_signed, field->filter_type); if (WARN_ON_ONCE(ret)) { pr_err("error code is %d\n", ret); break; } offset += field->size; } } return ret; } static int event_create_dir(struct dentry *parent, struct trace_event_file *file) { struct trace_event_call *call = file->event_call; struct trace_array *tr = file->tr; struct dentry *d_events; const char *name; int ret; /* * If the trace point header did not define TRACE_SYSTEM * then the system would be called "TRACE_SYSTEM". */ if (strcmp(call->class->system, TRACE_SYSTEM) != 0) { d_events = event_subsystem_dir(tr, call->class->system, file, parent); if (!d_events) return -ENOMEM; } else d_events = parent; name = trace_event_name(call); file->dir = tracefs_create_dir(name, d_events); if (!file->dir) { pr_warn("Could not create tracefs '%s' directory\n", name); return -1; } if (call->class->reg && !(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)) trace_create_file("enable", 0644, file->dir, file, &ftrace_enable_fops); #ifdef CONFIG_PERF_EVENTS if (call->event.type && call->class->reg) trace_create_file("id", 0444, file->dir, (void *)(long)call->event.type, &ftrace_event_id_fops); #endif ret = event_define_fields(call); if (ret < 0) { pr_warn("Could not initialize trace point events/%s\n", name); return ret; } /* * Only event directories that can be enabled should have * triggers or filters. */ if (!(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)) { trace_create_file("filter", 0644, file->dir, file, &ftrace_event_filter_fops); trace_create_file("trigger", 0644, file->dir, file, &event_trigger_fops); } #ifdef CONFIG_HIST_TRIGGERS trace_create_file("hist", 0444, file->dir, file, &event_hist_fops); #endif #ifdef CONFIG_HIST_TRIGGERS_DEBUG trace_create_file("hist_debug", 0444, file->dir, file, &event_hist_debug_fops); #endif trace_create_file("format", 0444, file->dir, call, &ftrace_event_format_fops); #ifdef CONFIG_TRACE_EVENT_INJECT if (call->event.type && call->class->reg) trace_create_file("inject", 0200, file->dir, file, &event_inject_fops); #endif return 0; } static void remove_event_from_tracers(struct trace_event_call *call) { struct trace_event_file *file; struct trace_array *tr; do_for_each_event_file_safe(tr, file) { if (file->event_call != call) continue; remove_event_file_dir(file); /* * The do_for_each_event_file_safe() is * a double loop. After finding the call for this * trace_array, we use break to jump to the next * trace_array. */ break; } while_for_each_event_file(); } static void event_remove(struct trace_event_call *call) { struct trace_array *tr; struct trace_event_file *file; do_for_each_event_file(tr, file) { if (file->event_call != call) continue; if (file->flags & EVENT_FILE_FL_WAS_ENABLED) tr->clear_trace = true; ftrace_event_enable_disable(file, 0); /* * The do_for_each_event_file() is * a double loop. After finding the call for this * trace_array, we use break to jump to the next * trace_array. */ break; } while_for_each_event_file(); if (call->event.funcs) __unregister_trace_event(&call->event); remove_event_from_tracers(call); list_del(&call->list); } static int event_init(struct trace_event_call *call) { int ret = 0; const char *name; name = trace_event_name(call); if (WARN_ON(!name)) return -EINVAL; if (call->class->raw_init) { ret = call->class->raw_init(call); if (ret < 0 && ret != -ENOSYS) pr_warn("Could not initialize trace events/%s\n", name); } return ret; } static int __register_event(struct trace_event_call *call, struct module *mod) { int ret; ret = event_init(call); if (ret < 0) return ret; list_add(&call->list, &ftrace_events); call->mod = mod; return 0; } static char *eval_replace(char *ptr, struct trace_eval_map *map, int len) { int rlen; int elen; /* Find the length of the eval value as a string */ elen = snprintf(ptr, 0, "%ld", map->eval_value); /* Make sure there's enough room to replace the string with the value */ if (len < elen) return NULL; snprintf(ptr, elen + 1, "%ld", map->eval_value); /* Get the rest of the string of ptr */ rlen = strlen(ptr + len); memmove(ptr + elen, ptr + len, rlen); /* Make sure we end the new string */ ptr[elen + rlen] = 0; return ptr + elen; } static void update_event_printk(struct trace_event_call *call, struct trace_eval_map *map) { char *ptr; int quote = 0; int len = strlen(map->eval_string); for (ptr = call->print_fmt; *ptr; ptr++) { if (*ptr == '\\') { ptr++; /* paranoid */ if (!*ptr) break; continue; } if (*ptr == '"') { quote ^= 1; continue; } if (quote) continue; if (isdigit(*ptr)) { /* skip numbers */ do { ptr++; /* Check for alpha chars like ULL */ } while (isalnum(*ptr)); if (!*ptr) break; /* * A number must have some kind of delimiter after * it, and we can ignore that too. */ continue; } if (isalpha(*ptr) || *ptr == '_') { if (strncmp(map->eval_string, ptr, len) == 0 && !isalnum(ptr[len]) && ptr[len] != '_') { ptr = eval_replace(ptr, map, len); /* enum/sizeof string smaller than value */ if (WARN_ON_ONCE(!ptr)) return; /* * No need to decrement here, as eval_replace() * returns the pointer to the character passed * the eval, and two evals can not be placed * back to back without something in between. * We can skip that something in between. */ continue; } skip_more: do { ptr++; } while (isalnum(*ptr) || *ptr == '_'); if (!*ptr) break; /* * If what comes after this variable is a '.' or * '->' then we can continue to ignore that string. */ if (*ptr == '.' || (ptr[0] == '-' && ptr[1] == '>')) { ptr += *ptr == '.' ? 1 : 2; if (!*ptr) break; goto skip_more; } /* * Once again, we can skip the delimiter that came * after the string. */ continue; } } } void trace_event_eval_update(struct trace_eval_map **map, int len) { struct trace_event_call *call, *p; const char *last_system = NULL; bool first = false; int last_i; int i; down_write(&trace_event_sem); list_for_each_entry_safe(call, p, &ftrace_events, list) { /* events are usually grouped together with systems */ if (!last_system || call->class->system != last_system) { first = true; last_i = 0; last_system = call->class->system; } /* * Since calls are grouped by systems, the likelyhood that the * next call in the iteration belongs to the same system as the * previous call is high. As an optimization, we skip seaching * for a map[] that matches the call's system if the last call * was from the same system. That's what last_i is for. If the * call has the same system as the previous call, then last_i * will be the index of the first map[] that has a matching * system. */ for (i = last_i; i < len; i++) { if (call->class->system == map[i]->system) { /* Save the first system if need be */ if (first) { last_i = i; first = false; } update_event_printk(call, map[i]); } } } up_write(&trace_event_sem); } static struct trace_event_file * trace_create_new_event(struct trace_event_call *call, struct trace_array *tr) { struct trace_pid_list *no_pid_list; struct trace_pid_list *pid_list; struct trace_event_file *file; file = kmem_cache_alloc(file_cachep, GFP_TRACE); if (!file) return NULL; pid_list = rcu_dereference_protected(tr->filtered_pids, lockdep_is_held(&event_mutex)); no_pid_list = rcu_dereference_protected(tr->filtered_no_pids, lockdep_is_held(&event_mutex)); if (pid_list || no_pid_list) file->flags |= EVENT_FILE_FL_PID_FILTER; file->event_call = call; file->tr = tr; atomic_set(&file->sm_ref, 0); atomic_set(&file->tm_ref, 0); INIT_LIST_HEAD(&file->triggers); list_add(&file->list, &tr->events); return file; } /* Add an event to a trace directory */ static int __trace_add_new_event(struct trace_event_call *call, struct trace_array *tr) { struct trace_event_file *file; file = trace_create_new_event(call, tr); if (!file) return -ENOMEM; if (eventdir_initialized) return event_create_dir(tr->event_dir, file); else return event_define_fields(call); } /* * Just create a decriptor for early init. A descriptor is required * for enabling events at boot. We want to enable events before * the filesystem is initialized. */ static int __trace_early_add_new_event(struct trace_event_call *call, struct trace_array *tr) { struct trace_event_file *file; file = trace_create_new_event(call, tr); if (!file) return -ENOMEM; return event_define_fields(call); } struct ftrace_module_file_ops; static void __add_event_to_tracers(struct trace_event_call *call); /* Add an additional event_call dynamically */ int trace_add_event_call(struct trace_event_call *call) { int ret; lockdep_assert_held(&event_mutex); mutex_lock(&trace_types_lock); ret = __register_event(call, NULL); if (ret >= 0) __add_event_to_tracers(call); mutex_unlock(&trace_types_lock); return ret; } /* * Must be called under locking of trace_types_lock, event_mutex and * trace_event_sem. */ static void __trace_remove_event_call(struct trace_event_call *call) { event_remove(call); trace_destroy_fields(call); free_event_filter(call->filter); call->filter = NULL; } static int probe_remove_event_call(struct trace_event_call *call) { struct trace_array *tr; struct trace_event_file *file; #ifdef CONFIG_PERF_EVENTS if (call->perf_refcount) return -EBUSY; #endif do_for_each_event_file(tr, file) { if (file->event_call != call) continue; /* * We can't rely on ftrace_event_enable_disable(enable => 0) * we are going to do, EVENT_FILE_FL_SOFT_MODE can suppress * TRACE_REG_UNREGISTER. */ if (file->flags & EVENT_FILE_FL_ENABLED) return -EBUSY; /* * The do_for_each_event_file_safe() is * a double loop. After finding the call for this * trace_array, we use break to jump to the next * trace_array. */ break; } while_for_each_event_file(); __trace_remove_event_call(call); return 0; } /* Remove an event_call */ int trace_remove_event_call(struct trace_event_call *call) { int ret; lockdep_assert_held(&event_mutex); mutex_lock(&trace_types_lock); down_write(&trace_event_sem); ret = probe_remove_event_call(call); up_write(&trace_event_sem); mutex_unlock(&trace_types_lock); return ret; } #define for_each_event(event, start, end) \ for (event = start; \ (unsigned long)event < (unsigned long)end; \ event++) #ifdef CONFIG_MODULES static void trace_module_add_events(struct module *mod) { struct trace_event_call **call, **start, **end; if (!mod->num_trace_events) return; /* Don't add infrastructure for mods without tracepoints */ if (trace_module_has_bad_taint(mod)) { pr_err("%s: module has bad taint, not creating trace events\n", mod->name); return; } start = mod->trace_events; end = mod->trace_events + mod->num_trace_events; for_each_event(call, start, end) { __register_event(*call, mod); __add_event_to_tracers(*call); } } static void trace_module_remove_events(struct module *mod) { struct trace_event_call *call, *p; down_write(&trace_event_sem); list_for_each_entry_safe(call, p, &ftrace_events, list) { if (call->mod == mod) __trace_remove_event_call(call); } up_write(&trace_event_sem); /* * It is safest to reset the ring buffer if the module being unloaded * registered any events that were used. The only worry is if * a new module gets loaded, and takes on the same id as the events * of this module. When printing out the buffer, traced events left * over from this module may be passed to the new module events and * unexpected results may occur. */ tracing_reset_all_online_cpus(); } static int trace_module_notify(struct notifier_block *self, unsigned long val, void *data) { struct module *mod = data; mutex_lock(&event_mutex); mutex_lock(&trace_types_lock); switch (val) { case MODULE_STATE_COMING: trace_module_add_events(mod); break; case MODULE_STATE_GOING: trace_module_remove_events(mod); break; } mutex_unlock(&trace_types_lock); mutex_unlock(&event_mutex); return NOTIFY_OK; } static struct notifier_block trace_module_nb = { .notifier_call = trace_module_notify, .priority = 1, /* higher than trace.c module notify */ }; #endif /* CONFIG_MODULES */ /* Create a new event directory structure for a trace directory. */ static void __trace_add_event_dirs(struct trace_array *tr) { struct trace_event_call *call; int ret; list_for_each_entry(call, &ftrace_events, list) { ret = __trace_add_new_event(call, tr); if (ret < 0) pr_warn("Could not create directory for event %s\n", trace_event_name(call)); } } /* Returns any file that matches the system and event */ struct trace_event_file * __find_event_file(struct trace_array *tr, const char *system, const char *event) { struct trace_event_file *file; struct trace_event_call *call; const char *name; list_for_each_entry(file, &tr->events, list) { call = file->event_call; name = trace_event_name(call); if (!name || !call->class) continue; if (strcmp(event, name) == 0 && strcmp(system, call->class->system) == 0) return file; } return NULL; } /* Returns valid trace event files that match system and event */ struct trace_event_file * find_event_file(struct trace_array *tr, const char *system, const char *event) { struct trace_event_file *file; file = __find_event_file(tr, system, event); if (!file || !file->event_call->class->reg || file->event_call->flags & TRACE_EVENT_FL_IGNORE_ENABLE) return NULL; return file; } /** * trace_get_event_file - Find and return a trace event file * @instance: The name of the trace instance containing the event * @system: The name of the system containing the event * @event: The name of the event * * Return a trace event file given the trace instance name, trace * system, and trace event name. If the instance name is NULL, it * refers to the top-level trace array. * * This function will look it up and return it if found, after calling * trace_array_get() to prevent the instance from going away, and * increment the event's module refcount to prevent it from being * removed. * * To release the file, call trace_put_event_file(), which will call * trace_array_put() and decrement the event's module refcount. * * Return: The trace event on success, ERR_PTR otherwise. */ struct trace_event_file *trace_get_event_file(const char *instance, const char *system, const char *event) { struct trace_array *tr = top_trace_array(); struct trace_event_file *file = NULL; int ret = -EINVAL; if (instance) { tr = trace_array_find_get(instance); if (!tr) return ERR_PTR(-ENOENT); } else { ret = trace_array_get(tr); if (ret) return ERR_PTR(ret); } mutex_lock(&event_mutex); file = find_event_file(tr, system, event); if (!file) { trace_array_put(tr); ret = -EINVAL; goto out; } /* Don't let event modules unload while in use */ ret = try_module_get(file->event_call->mod); if (!ret) { trace_array_put(tr); ret = -EBUSY; goto out; } ret = 0; out: mutex_unlock(&event_mutex); if (ret) file = ERR_PTR(ret); return file; } EXPORT_SYMBOL_GPL(trace_get_event_file); /** * trace_put_event_file - Release a file from trace_get_event_file() * @file: The trace event file * * If a file was retrieved using trace_get_event_file(), this should * be called when it's no longer needed. It will cancel the previous * trace_array_get() called by that function, and decrement the * event's module refcount. */ void trace_put_event_file(struct trace_event_file *file) { mutex_lock(&event_mutex); module_put(file->event_call->mod); mutex_unlock(&event_mutex); trace_array_put(file->tr); } EXPORT_SYMBOL_GPL(trace_put_event_file); #ifdef CONFIG_DYNAMIC_FTRACE /* Avoid typos */ #define ENABLE_EVENT_STR "enable_event" #define DISABLE_EVENT_STR "disable_event" struct event_probe_data { struct trace_event_file *file; unsigned long count; int ref; bool enable; }; static void update_event_probe(struct event_probe_data *data) { if (data->enable) clear_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &data->file->flags); else set_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &data->file->flags); } static void event_enable_probe(unsigned long ip, unsigned long parent_ip, struct trace_array *tr, struct ftrace_probe_ops *ops, void *data) { struct ftrace_func_mapper *mapper = data; struct event_probe_data *edata; void **pdata; pdata = ftrace_func_mapper_find_ip(mapper, ip); if (!pdata || !*pdata) return; edata = *pdata; update_event_probe(edata); } static void event_enable_count_probe(unsigned long ip, unsigned long parent_ip, struct trace_array *tr, struct ftrace_probe_ops *ops, void *data) { struct ftrace_func_mapper *mapper = data; struct event_probe_data *edata; void **pdata; pdata = ftrace_func_mapper_find_ip(mapper, ip); if (!pdata || !*pdata) return; edata = *pdata; if (!edata->count) return; /* Skip if the event is in a state we want to switch to */ if (edata->enable == !(edata->file->flags & EVENT_FILE_FL_SOFT_DISABLED)) return; if (edata->count != -1) (edata->count)--; update_event_probe(edata); } static int event_enable_print(struct seq_file *m, unsigned long ip, struct ftrace_probe_ops *ops, void *data) { struct ftrace_func_mapper *mapper = data; struct event_probe_data *edata; void **pdata; pdata = ftrace_func_mapper_find_ip(mapper, ip); if (WARN_ON_ONCE(!pdata || !*pdata)) return 0; edata = *pdata; seq_printf(m, "%ps:", (void *)ip); seq_printf(m, "%s:%s:%s", edata->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR, edata->file->event_call->class->system, trace_event_name(edata->file->event_call)); if (edata->count == -1) seq_puts(m, ":unlimited\n"); else seq_printf(m, ":count=%ld\n", edata->count); return 0; } static int event_enable_init(struct ftrace_probe_ops *ops, struct trace_array *tr, unsigned long ip, void *init_data, void **data) { struct ftrace_func_mapper *mapper = *data; struct event_probe_data *edata = init_data; int ret; if (!mapper) { mapper = allocate_ftrace_func_mapper(); if (!mapper) return -ENODEV; *data = mapper; } ret = ftrace_func_mapper_add_ip(mapper, ip, edata); if (ret < 0) return ret; edata->ref++; return 0; } static int free_probe_data(void *data) { struct event_probe_data *edata = data; edata->ref--; if (!edata->ref) { /* Remove the SOFT_MODE flag */ __ftrace_event_enable_disable(edata->file, 0, 1); module_put(edata->file->event_call->mod); kfree(edata); } return 0; } static void event_enable_free(struct ftrace_probe_ops *ops, struct trace_array *tr, unsigned long ip, void *data) { struct ftrace_func_mapper *mapper = data; struct event_probe_data *edata; if (!ip) { if (!mapper) return; free_ftrace_func_mapper(mapper, free_probe_data); return; } edata = ftrace_func_mapper_remove_ip(mapper, ip); if (WARN_ON_ONCE(!edata)) return; if (WARN_ON_ONCE(edata->ref <= 0)) return; free_probe_data(edata); } static struct ftrace_probe_ops event_enable_probe_ops = { .func = event_enable_probe, .print = event_enable_print, .init = event_enable_init, .free = event_enable_free, }; static struct ftrace_probe_ops event_enable_count_probe_ops = { .func = event_enable_count_probe, .print = event_enable_print, .init = event_enable_init, .free = event_enable_free, }; static struct ftrace_probe_ops event_disable_probe_ops = { .func = event_enable_probe, .print = event_enable_print, .init = event_enable_init, .free = event_enable_free, }; static struct ftrace_probe_ops event_disable_count_probe_ops = { .func = event_enable_count_probe, .print = event_enable_print, .init = event_enable_init, .free = event_enable_free, }; static int event_enable_func(struct trace_array *tr, struct ftrace_hash *hash, char *glob, char *cmd, char *param, int enabled) { struct trace_event_file *file; struct ftrace_probe_ops *ops; struct event_probe_data *data; const char *system; const char *event; char *number; bool enable; int ret; if (!tr) return -ENODEV; /* hash funcs only work with set_ftrace_filter */ if (!enabled || !param) return -EINVAL; system = strsep(&param, ":"); if (!param) return -EINVAL; event = strsep(&param, ":"); mutex_lock(&event_mutex); ret = -EINVAL; file = find_event_file(tr, system, event); if (!file) goto out; enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; if (enable) ops = param ? &event_enable_count_probe_ops : &event_enable_probe_ops; else ops = param ? &event_disable_count_probe_ops : &event_disable_probe_ops; if (glob[0] == '!') { ret = unregister_ftrace_function_probe_func(glob+1, tr, ops); goto out; } ret = -ENOMEM; data = kzalloc(sizeof(*data), GFP_KERNEL); if (!data) goto out; data->enable = enable; data->count = -1; data->file = file; if (!param) goto out_reg; number = strsep(&param, ":"); ret = -EINVAL; if (!strlen(number)) goto out_free; /* * We use the callback data field (which is a pointer) * as our counter. */ ret = kstrtoul(number, 0, &data->count); if (ret) goto out_free; out_reg: /* Don't let event modules unload while probe registered */ ret = try_module_get(file->event_call->mod); if (!ret) { ret = -EBUSY; goto out_free; } ret = __ftrace_event_enable_disable(file, 1, 1); if (ret < 0) goto out_put; ret = register_ftrace_function_probe(glob, tr, ops, data); /* * The above returns on success the # of functions enabled, * but if it didn't find any functions it returns zero. * Consider no functions a failure too. */ if (!ret) { ret = -ENOENT; goto out_disable; } else if (ret < 0) goto out_disable; /* Just return zero, not the number of enabled functions */ ret = 0; out: mutex_unlock(&event_mutex); return ret; out_disable: __ftrace_event_enable_disable(file, 0, 1); out_put: module_put(file->event_call->mod); out_free: kfree(data); goto out; } static struct ftrace_func_command event_enable_cmd = { .name = ENABLE_EVENT_STR, .func = event_enable_func, }; static struct ftrace_func_command event_disable_cmd = { .name = DISABLE_EVENT_STR, .func = event_enable_func, }; static __init int register_event_cmds(void) { int ret; ret = register_ftrace_command(&event_enable_cmd); if (WARN_ON(ret < 0)) return ret; ret = register_ftrace_command(&event_disable_cmd); if (WARN_ON(ret < 0)) unregister_ftrace_command(&event_enable_cmd); return ret; } #else static inline int register_event_cmds(void) { return 0; } #endif /* CONFIG_DYNAMIC_FTRACE */ /* * The top level array and trace arrays created by boot-time tracing * have already had its trace_event_file descriptors created in order * to allow for early events to be recorded. * This function is called after the tracefs has been initialized, * and we now have to create the files associated to the events. */ static void __trace_early_add_event_dirs(struct trace_array *tr) { struct trace_event_file *file; int ret; list_for_each_entry(file, &tr->events, list) { ret = event_create_dir(tr->event_dir, file); if (ret < 0) pr_warn("Could not create directory for event %s\n", trace_event_name(file->event_call)); } } /* * For early boot up, the top trace array and the trace arrays created * by boot-time tracing require to have a list of events that can be * enabled. This must be done before the filesystem is set up in order * to allow events to be traced early. */ void __trace_early_add_events(struct trace_array *tr) { struct trace_event_call *call; int ret; list_for_each_entry(call, &ftrace_events, list) { /* Early boot up should not have any modules loaded */ if (WARN_ON_ONCE(call->mod)) continue; ret = __trace_early_add_new_event(call, tr); if (ret < 0) pr_warn("Could not create early event %s\n", trace_event_name(call)); } } /* Remove the event directory structure for a trace directory. */ static void __trace_remove_event_dirs(struct trace_array *tr) { struct trace_event_file *file, *next; list_for_each_entry_safe(file, next, &tr->events, list) remove_event_file_dir(file); } static void __add_event_to_tracers(struct trace_event_call *call) { struct trace_array *tr; list_for_each_entry(tr, &ftrace_trace_arrays, list) __trace_add_new_event(call, tr); } extern struct trace_event_call *__start_ftrace_events[]; extern struct trace_event_call *__stop_ftrace_events[]; static char bootup_event_buf[COMMAND_LINE_SIZE] __initdata; static __init int setup_trace_event(char *str) { strlcpy(bootup_event_buf, str, COMMAND_LINE_SIZE); ring_buffer_expanded = true; disable_tracing_selftest("running event tracing"); return 1; } __setup("trace_event=", setup_trace_event); /* Expects to have event_mutex held when called */ static int create_event_toplevel_files(struct dentry *parent, struct trace_array *tr) { struct dentry *d_events; struct dentry *entry; entry = tracefs_create_file("set_event", 0644, parent, tr, &ftrace_set_event_fops); if (!entry) { pr_warn("Could not create tracefs 'set_event' entry\n"); return -ENOMEM; } d_events = tracefs_create_dir("events", parent); if (!d_events) { pr_warn("Could not create tracefs 'events' directory\n"); return -ENOMEM; } entry = trace_create_file("enable", 0644, d_events, tr, &ftrace_tr_enable_fops); if (!entry) { pr_warn("Could not create tracefs 'enable' entry\n"); return -ENOMEM; } /* There are not as crucial, just warn if they are not created */ entry = tracefs_create_file("set_event_pid", 0644, parent, tr, &ftrace_set_event_pid_fops); if (!entry) pr_warn("Could not create tracefs 'set_event_pid' entry\n"); entry = tracefs_create_file("set_event_notrace_pid", 0644, parent, tr, &ftrace_set_event_notrace_pid_fops); if (!entry) pr_warn("Could not create tracefs 'set_event_notrace_pid' entry\n"); /* ring buffer internal formats */ entry = trace_create_file("header_page", 0444, d_events, ring_buffer_print_page_header, &ftrace_show_header_fops); if (!entry) pr_warn("Could not create tracefs 'header_page' entry\n"); entry = trace_create_file("header_event", 0444, d_events, ring_buffer_print_entry_header, &ftrace_show_header_fops); if (!entry) pr_warn("Could not create tracefs 'header_event' entry\n"); tr->event_dir = d_events; return 0; } /** * event_trace_add_tracer - add a instance of a trace_array to events * @parent: The parent dentry to place the files/directories for events in * @tr: The trace array associated with these events * * When a new instance is created, it needs to set up its events * directory, as well as other files associated with events. It also * creates the event hierachry in the @parent/events directory. * * Returns 0 on success. * * Must be called with event_mutex held. */ int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr) { int ret; lockdep_assert_held(&event_mutex); ret = create_event_toplevel_files(parent, tr); if (ret) goto out; down_write(&trace_event_sem); /* If tr already has the event list, it is initialized in early boot. */ if (unlikely(!list_empty(&tr->events))) __trace_early_add_event_dirs(tr); else __trace_add_event_dirs(tr); up_write(&trace_event_sem); out: return ret; } /* * The top trace array already had its file descriptors created. * Now the files themselves need to be created. */ static __init int early_event_add_tracer(struct dentry *parent, struct trace_array *tr) { int ret; mutex_lock(&event_mutex); ret = create_event_toplevel_files(parent, tr); if (ret) goto out_unlock; down_write(&trace_event_sem); __trace_early_add_event_dirs(tr); up_write(&trace_event_sem); out_unlock: mutex_unlock(&event_mutex); return ret; } /* Must be called with event_mutex held */ int event_trace_del_tracer(struct trace_array *tr) { lockdep_assert_held(&event_mutex); /* Disable any event triggers and associated soft-disabled events */ clear_event_triggers(tr); /* Clear the pid list */ __ftrace_clear_event_pids(tr, TRACE_PIDS | TRACE_NO_PIDS); /* Disable any running events */ __ftrace_set_clr_event_nolock(tr, NULL, NULL, NULL, 0); /* Make sure no more events are being executed */ tracepoint_synchronize_unregister(); down_write(&trace_event_sem); __trace_remove_event_dirs(tr); tracefs_remove(tr->event_dir); up_write(&trace_event_sem); tr->event_dir = NULL; return 0; } static __init int event_trace_memsetup(void) { field_cachep = KMEM_CACHE(ftrace_event_field, SLAB_PANIC); file_cachep = KMEM_CACHE(trace_event_file, SLAB_PANIC); return 0; } static __init void early_enable_events(struct trace_array *tr, bool disable_first) { char *buf = bootup_event_buf; char *token; int ret; while (true) { token = strsep(&buf, ","); if (!token) break; if (*token) { /* Restarting syscalls requires that we stop them first */ if (disable_first) ftrace_set_clr_event(tr, token, 0); ret = ftrace_set_clr_event(tr, token, 1); if (ret) pr_warn("Failed to enable trace event: %s\n", token); } /* Put back the comma to allow this to be called again */ if (buf) *(buf - 1) = ','; } } static __init int event_trace_enable(void) { struct trace_array *tr = top_trace_array(); struct trace_event_call **iter, *call; int ret; if (!tr) return -ENODEV; for_each_event(iter, __start_ftrace_events, __stop_ftrace_events) { call = *iter; ret = event_init(call); if (!ret) list_add(&call->list, &ftrace_events); } /* * We need the top trace array to have a working set of trace * points at early init, before the debug files and directories * are created. Create the file entries now, and attach them * to the actual file dentries later. */ __trace_early_add_events(tr); early_enable_events(tr, false); trace_printk_start_comm(); register_event_cmds(); register_trigger_cmds(); return 0; } /* * event_trace_enable() is called from trace_event_init() first to * initialize events and perhaps start any events that are on the * command line. Unfortunately, there are some events that will not * start this early, like the system call tracepoints that need * to set the TIF_SYSCALL_TRACEPOINT flag of pid 1. But event_trace_enable() * is called before pid 1 starts, and this flag is never set, making * the syscall tracepoint never get reached, but the event is enabled * regardless (and not doing anything). */ static __init int event_trace_enable_again(void) { struct trace_array *tr; tr = top_trace_array(); if (!tr) return -ENODEV; early_enable_events(tr, true); return 0; } early_initcall(event_trace_enable_again); /* Init fields which doesn't related to the tracefs */ static __init int event_trace_init_fields(void) { if (trace_define_generic_fields()) pr_warn("tracing: Failed to allocated generic fields"); if (trace_define_common_fields()) pr_warn("tracing: Failed to allocate common fields"); return 0; } __init int event_trace_init(void) { struct trace_array *tr; struct dentry *entry; int ret; tr = top_trace_array(); if (!tr) return -ENODEV; entry = tracefs_create_file("available_events", 0444, NULL, tr, &ftrace_avail_fops); if (!entry) pr_warn("Could not create tracefs 'available_events' entry\n"); ret = early_event_add_tracer(NULL, tr); if (ret) return ret; #ifdef CONFIG_MODULES ret = register_module_notifier(&trace_module_nb); if (ret) pr_warn("Failed to register trace events module notifier\n"); #endif eventdir_initialized = true; return 0; } void __init trace_event_init(void) { event_trace_memsetup(); init_ftrace_syscalls(); event_trace_enable(); event_trace_init_fields(); } #ifdef CONFIG_EVENT_TRACE_STARTUP_TEST static DEFINE_SPINLOCK(test_spinlock); static DEFINE_SPINLOCK(test_spinlock_irq); static DEFINE_MUTEX(test_mutex); static __init void test_work(struct work_struct *dummy) { spin_lock(&test_spinlock); spin_lock_irq(&test_spinlock_irq); udelay(1); spin_unlock_irq(&test_spinlock_irq); spin_unlock(&test_spinlock); mutex_lock(&test_mutex); msleep(1); mutex_unlock(&test_mutex); } static __init int event_test_thread(void *unused) { void *test_malloc; test_malloc = kmalloc(1234, GFP_KERNEL); if (!test_malloc) pr_info("failed to kmalloc\n"); schedule_on_each_cpu(test_work); kfree(test_malloc); set_current_state(TASK_INTERRUPTIBLE); while (!kthread_should_stop()) { schedule(); set_current_state(TASK_INTERRUPTIBLE); } __set_current_state(TASK_RUNNING); return 0; } /* * Do various things that may trigger events. */ static __init void event_test_stuff(void) { struct task_struct *test_thread; test_thread = kthread_run(event_test_thread, NULL, "test-events"); msleep(1); kthread_stop(test_thread); } /* * For every trace event defined, we will test each trace point separately, * and then by groups, and finally all trace points. */ static __init void event_trace_self_tests(void) { struct trace_subsystem_dir *dir; struct trace_event_file *file; struct trace_event_call *call; struct event_subsystem *system; struct trace_array *tr; int ret; tr = top_trace_array(); if (!tr) return; pr_info("Running tests on trace events:\n"); list_for_each_entry(file, &tr->events, list) { call = file->event_call; /* Only test those that have a probe */ if (!call->class || !call->class->probe) continue; /* * Testing syscall events here is pretty useless, but * we still do it if configured. But this is time consuming. * What we really need is a user thread to perform the * syscalls as we test. */ #ifndef CONFIG_EVENT_TRACE_TEST_SYSCALLS if (call->class->system && strcmp(call->class->system, "syscalls") == 0) continue; #endif pr_info("Testing event %s: ", trace_event_name(call)); /* * If an event is already enabled, someone is using * it and the self test should not be on. */ if (file->flags & EVENT_FILE_FL_ENABLED) { pr_warn("Enabled event during self test!\n"); WARN_ON_ONCE(1); continue; } ftrace_event_enable_disable(file, 1); event_test_stuff(); ftrace_event_enable_disable(file, 0); pr_cont("OK\n"); } /* Now test at the sub system level */ pr_info("Running tests on trace event systems:\n"); list_for_each_entry(dir, &tr->systems, list) { system = dir->subsystem; /* the ftrace system is special, skip it */ if (strcmp(system->name, "ftrace") == 0) continue; pr_info("Testing event system %s: ", system->name); ret = __ftrace_set_clr_event(tr, NULL, system->name, NULL, 1); if (WARN_ON_ONCE(ret)) { pr_warn("error enabling system %s\n", system->name); continue; } event_test_stuff(); ret = __ftrace_set_clr_event(tr, NULL, system->name, NULL, 0); if (WARN_ON_ONCE(ret)) { pr_warn("error disabling system %s\n", system->name); continue; } pr_cont("OK\n"); } /* Test with all events enabled */ pr_info("Running tests on all trace events:\n"); pr_info("Testing all events: "); ret = __ftrace_set_clr_event(tr, NULL, NULL, NULL, 1); if (WARN_ON_ONCE(ret)) { pr_warn("error enabling all events\n"); return; } event_test_stuff(); /* reset sysname */ ret = __ftrace_set_clr_event(tr, NULL, NULL, NULL, 0); if (WARN_ON_ONCE(ret)) { pr_warn("error disabling all events\n"); return; } pr_cont("OK\n"); } #ifdef CONFIG_FUNCTION_TRACER static DEFINE_PER_CPU(atomic_t, ftrace_test_event_disable); static struct trace_event_file event_trace_file __initdata; static void __init function_test_events_call(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *op, struct pt_regs *pt_regs) { struct trace_buffer *buffer; struct ring_buffer_event *event; struct ftrace_entry *entry; unsigned long flags; long disabled; int cpu; int pc; pc = preempt_count(); preempt_disable_notrace(); cpu = raw_smp_processor_id(); disabled = atomic_inc_return(&per_cpu(ftrace_test_event_disable, cpu)); if (disabled != 1) goto out; local_save_flags(flags); event = trace_event_buffer_lock_reserve(&buffer, &event_trace_file, TRACE_FN, sizeof(*entry), flags, pc); if (!event) goto out; entry = ring_buffer_event_data(event); entry->ip = ip; entry->parent_ip = parent_ip; event_trigger_unlock_commit(&event_trace_file, buffer, event, entry, flags, pc); out: atomic_dec(&per_cpu(ftrace_test_event_disable, cpu)); preempt_enable_notrace(); } static struct ftrace_ops trace_ops __initdata = { .func = function_test_events_call, .flags = FTRACE_OPS_FL_RECURSION_SAFE, }; static __init void event_trace_self_test_with_function(void) { int ret; event_trace_file.tr = top_trace_array(); if (WARN_ON(!event_trace_file.tr)) return; ret = register_ftrace_function(&trace_ops); if (WARN_ON(ret < 0)) { pr_info("Failed to enable function tracer for event tests\n"); return; } pr_info("Running tests again, along with the function tracer\n"); event_trace_self_tests(); unregister_ftrace_function(&trace_ops); } #else static __init void event_trace_self_test_with_function(void) { } #endif static __init int event_trace_self_tests_init(void) { if (!tracing_selftest_disabled) { event_trace_self_tests(); event_trace_self_test_with_function(); } return 0; } late_initcall(event_trace_self_tests_init); #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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 /* SPDX-License-Identifier: GPL-2.0 */ #ifndef BLK_MQ_H #define BLK_MQ_H #include <linux/blkdev.h> #include <linux/sbitmap.h> #include <linux/srcu.h> struct blk_mq_tags; struct blk_flush_queue; /** * struct blk_mq_hw_ctx - State for a hardware queue facing the hardware * block device */ struct blk_mq_hw_ctx { struct { /** @lock: Protects the dispatch list. */ spinlock_t lock; /** * @dispatch: Used for requests that are ready to be * dispatched to the hardware but for some reason (e.g. lack of * resources) could not be sent to the hardware. As soon as the * driver can send new requests, requests at this list will * be sent first for a fairer dispatch. */ struct list_head dispatch; /** * @state: BLK_MQ_S_* flags. Defines the state of the hw * queue (active, scheduled to restart, stopped). */ unsigned long state; } ____cacheline_aligned_in_smp; /** * @run_work: Used for scheduling a hardware queue run at a later time. */ struct delayed_work run_work; /** @cpumask: Map of available CPUs where this hctx can run. */ cpumask_var_t cpumask; /** * @next_cpu: Used by blk_mq_hctx_next_cpu() for round-robin CPU * selection from @cpumask. */ int next_cpu; /** * @next_cpu_batch: Counter of how many works left in the batch before * changing to the next CPU. */ int next_cpu_batch; /** @flags: BLK_MQ_F_* flags. Defines the behaviour of the queue. */ unsigned long flags; /** * @sched_data: Pointer owned by the IO scheduler attached to a request * queue. It's up to the IO scheduler how to use this pointer. */ void *sched_data; /** * @queue: Pointer to the request queue that owns this hardware context. */ struct request_queue *queue; /** @fq: Queue of requests that need to perform a flush operation. */ struct blk_flush_queue *fq; /** * @driver_data: Pointer to data owned by the block driver that created * this hctx */ void *driver_data; /** * @ctx_map: Bitmap for each software queue. If bit is on, there is a * pending request in that software queue. */ struct sbitmap ctx_map; /** * @dispatch_from: Software queue to be used when no scheduler was * selected. */ struct blk_mq_ctx *dispatch_from; /** * @dispatch_busy: Number used by blk_mq_update_dispatch_busy() to * decide if the hw_queue is busy using Exponential Weighted Moving * Average algorithm. */ unsigned int dispatch_busy; /** @type: HCTX_TYPE_* flags. Type of hardware queue. */ unsigned short type; /** @nr_ctx: Number of software queues. */ unsigned short nr_ctx; /** @ctxs: Array of software queues. */ struct blk_mq_ctx **ctxs; /** @dispatch_wait_lock: Lock for dispatch_wait queue. */ spinlock_t dispatch_wait_lock; /** * @dispatch_wait: Waitqueue to put requests when there is no tag * available at the moment, to wait for another try in the future. */ wait_queue_entry_t dispatch_wait; /** * @wait_index: Index of next available dispatch_wait queue to insert * requests. */ atomic_t wait_index; /** * @tags: Tags owned by the block driver. A tag at this set is only * assigned when a request is dispatched from a hardware queue. */ struct blk_mq_tags *tags; /** * @sched_tags: Tags owned by I/O scheduler. If there is an I/O * scheduler associated with a request queue, a tag is assigned when * that request is allocated. Else, this member is not used. */ struct blk_mq_tags *sched_tags; /** @queued: Number of queued requests. */ unsigned long queued; /** @run: Number of dispatched requests. */ unsigned long run; #define BLK_MQ_MAX_DISPATCH_ORDER 7 /** @dispatched: Number of dispatch requests by queue. */ unsigned long dispatched[BLK_MQ_MAX_DISPATCH_ORDER]; /** @numa_node: NUMA node the storage adapter has been connected to. */ unsigned int numa_node; /** @queue_num: Index of this hardware queue. */ unsigned int queue_num; /** * @nr_active: Number of active requests. Only used when a tag set is * shared across request queues. */ atomic_t nr_active; /** * @elevator_queued: Number of queued requests on hctx. */ atomic_t elevator_queued; /** @cpuhp_online: List to store request if CPU is going to die */ struct hlist_node cpuhp_online; /** @cpuhp_dead: List to store request if some CPU die. */ struct hlist_node cpuhp_dead; /** @kobj: Kernel object for sysfs. */ struct kobject kobj; /** @poll_considered: Count times blk_poll() was called. */ unsigned long poll_considered; /** @poll_invoked: Count how many requests blk_poll() polled. */ unsigned long poll_invoked; /** @poll_success: Count how many polled requests were completed. */ unsigned long poll_success; #ifdef CONFIG_BLK_DEBUG_FS /** * @debugfs_dir: debugfs directory for this hardware queue. Named * as cpu<cpu_number>. */ struct dentry *debugfs_dir; /** @sched_debugfs_dir: debugfs directory for the scheduler. */ struct dentry *sched_debugfs_dir; #endif /** * @hctx_list: if this hctx is not in use, this is an entry in * q->unused_hctx_list. */ struct list_head hctx_list; /** * @srcu: Sleepable RCU. Use as lock when type of the hardware queue is * blocking (BLK_MQ_F_BLOCKING). Must be the last member - see also * blk_mq_hw_ctx_size(). */ struct srcu_struct srcu[]; }; /** * struct blk_mq_queue_map - Map software queues to hardware queues * @mq_map: CPU ID to hardware queue index map. This is an array * with nr_cpu_ids elements. Each element has a value in the range * [@queue_offset, @queue_offset + @nr_queues). * @nr_queues: Number of hardware queues to map CPU IDs onto. * @queue_offset: First hardware queue to map onto. Used by the PCIe NVMe * driver to map each hardware queue type (enum hctx_type) onto a distinct * set of hardware queues. */ struct blk_mq_queue_map { unsigned int *mq_map; unsigned int nr_queues; unsigned int queue_offset; }; /** * enum hctx_type - Type of hardware queue * @HCTX_TYPE_DEFAULT: All I/O not otherwise accounted for. * @HCTX_TYPE_READ: Just for READ I/O. * @HCTX_TYPE_POLL: Polled I/O of any kind. * @HCTX_MAX_TYPES: Number of types of hctx. */ enum hctx_type { HCTX_TYPE_DEFAULT, HCTX_TYPE_READ, HCTX_TYPE_POLL, HCTX_MAX_TYPES, }; /** * struct blk_mq_tag_set - tag set that can be shared between request queues * @map: One or more ctx -> hctx mappings. One map exists for each * hardware queue type (enum hctx_type) that the driver wishes * to support. There are no restrictions on maps being of the * same size, and it's perfectly legal to share maps between * types. * @nr_maps: Number of elements in the @map array. A number in the range * [1, HCTX_MAX_TYPES]. * @ops: Pointers to functions that implement block driver behavior. * @nr_hw_queues: Number of hardware queues supported by the block driver that * owns this data structure. * @queue_depth: Number of tags per hardware queue, reserved tags included. * @reserved_tags: Number of tags to set aside for BLK_MQ_REQ_RESERVED tag * allocations. * @cmd_size: Number of additional bytes to allocate per request. The block * driver owns these additional bytes. * @numa_node: NUMA node the storage adapter has been connected to. * @timeout: Request processing timeout in jiffies. * @flags: Zero or more BLK_MQ_F_* flags. * @driver_data: Pointer to data owned by the block driver that created this * tag set. * @active_queues_shared_sbitmap: * number of active request queues per tag set. * @__bitmap_tags: A shared tags sbitmap, used over all hctx's * @__breserved_tags: * A shared reserved tags sbitmap, used over all hctx's * @tags: Tag sets. One tag set per hardware queue. Has @nr_hw_queues * elements. * @tag_list_lock: Serializes tag_list accesses. * @tag_list: List of the request queues that use this tag set. See also * request_queue.tag_set_list. */ struct blk_mq_tag_set { struct blk_mq_queue_map map[HCTX_MAX_TYPES]; unsigned int nr_maps; const struct blk_mq_ops *ops; unsigned int nr_hw_queues; unsigned int queue_depth; unsigned int reserved_tags; unsigned int cmd_size; int numa_node; unsigned int timeout; unsigned int flags; void *driver_data; atomic_t active_queues_shared_sbitmap; struct sbitmap_queue __bitmap_tags; struct sbitmap_queue __breserved_tags; struct blk_mq_tags **tags; struct mutex tag_list_lock; struct list_head tag_list; }; /** * struct blk_mq_queue_data - Data about a request inserted in a queue * * @rq: Request pointer. * @last: If it is the last request in the queue. */ struct blk_mq_queue_data { struct request *rq; bool last; }; typedef bool (busy_iter_fn)(struct blk_mq_hw_ctx *, struct request *, void *, bool); typedef bool (busy_tag_iter_fn)(struct request *, void *, bool); /** * struct blk_mq_ops - Callback functions that implements block driver * behaviour. */ struct blk_mq_ops { /** * @queue_rq: Queue a new request from block IO. */ blk_status_t (*queue_rq)(struct blk_mq_hw_ctx *, const struct blk_mq_queue_data *); /** * @commit_rqs: If a driver uses bd->last to judge when to submit * requests to hardware, it must define this function. In case of errors * that make us stop issuing further requests, this hook serves the * purpose of kicking the hardware (which the last request otherwise * would have done). */ void (*commit_rqs)(struct blk_mq_hw_ctx *); /** * @get_budget: Reserve budget before queue request, once .queue_rq is * run, it is driver's responsibility to release the * reserved budget. Also we have to handle failure case * of .get_budget for avoiding I/O deadlock. */ bool (*get_budget)(struct request_queue *); /** * @put_budget: Release the reserved budget. */ void (*put_budget)(struct request_queue *); /** * @timeout: Called on request timeout. */ enum blk_eh_timer_return (*timeout)(struct request *, bool); /** * @poll: Called to poll for completion of a specific tag. */ int (*poll)(struct blk_mq_hw_ctx *); /** * @complete: Mark the request as complete. */ void (*complete)(struct request *); /** * @init_hctx: Called when the block layer side of a hardware queue has * been set up, allowing the driver to allocate/init matching * structures. */ int (*init_hctx)(struct blk_mq_hw_ctx *, void *, unsigned int); /** * @exit_hctx: Ditto for exit/teardown. */ void (*exit_hctx)(struct blk_mq_hw_ctx *, unsigned int); /** * @init_request: Called for every command allocated by the block layer * to allow the driver to set up driver specific data. * * Tag greater than or equal to queue_depth is for setting up * flush request. */ int (*init_request)(struct blk_mq_tag_set *set, struct request *, unsigned int, unsigned int); /** * @exit_request: Ditto for exit/teardown. */ void (*exit_request)(struct blk_mq_tag_set *set, struct request *, unsigned int); /** * @initialize_rq_fn: Called from inside blk_get_request(). */ void (*initialize_rq_fn)(struct request *rq); /** * @cleanup_rq: Called before freeing one request which isn't completed * yet, and usually for freeing the driver private data. */ void (*cleanup_rq)(struct request *); /** * @busy: If set, returns whether or not this queue currently is busy. */ bool (*busy)(struct request_queue *); /** * @map_queues: This allows drivers specify their own queue mapping by * overriding the setup-time function that builds the mq_map. */ int (*map_queues)(struct blk_mq_tag_set *set); #ifdef CONFIG_BLK_DEBUG_FS /** * @show_rq: Used by the debugfs implementation to show driver-specific * information about a request. */ void (*show_rq)(struct seq_file *m, struct request *rq); #endif }; enum { BLK_MQ_F_SHOULD_MERGE = 1 << 0, BLK_MQ_F_TAG_QUEUE_SHARED = 1 << 1, /* * Set when this device requires underlying blk-mq device for * completing IO: */ BLK_MQ_F_STACKING = 1 << 2, BLK_MQ_F_TAG_HCTX_SHARED = 1 << 3, BLK_MQ_F_BLOCKING = 1 << 5, BLK_MQ_F_NO_SCHED = 1 << 6, BLK_MQ_F_ALLOC_POLICY_START_BIT = 8, BLK_MQ_F_ALLOC_POLICY_BITS = 1, BLK_MQ_S_STOPPED = 0, BLK_MQ_S_TAG_ACTIVE = 1, BLK_MQ_S_SCHED_RESTART = 2, /* hw queue is inactive after all its CPUs become offline */ BLK_MQ_S_INACTIVE = 3, BLK_MQ_MAX_DEPTH = 10240, BLK_MQ_CPU_WORK_BATCH = 8, }; #define BLK_MQ_FLAG_TO_ALLOC_POLICY(flags) \ ((flags >> BLK_MQ_F_ALLOC_POLICY_START_BIT) & \ ((1 << BLK_MQ_F_ALLOC_POLICY_BITS) - 1)) #define BLK_ALLOC_POLICY_TO_MQ_FLAG(policy) \ ((policy & ((1 << BLK_MQ_F_ALLOC_POLICY_BITS) - 1)) \ << BLK_MQ_F_ALLOC_POLICY_START_BIT) struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *); struct request_queue *blk_mq_init_queue_data(struct blk_mq_tag_set *set, void *queuedata); struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set, struct request_queue *q, bool elevator_init); struct request_queue *blk_mq_init_sq_queue(struct blk_mq_tag_set *set, const struct blk_mq_ops *ops, unsigned int queue_depth, unsigned int set_flags); void blk_mq_unregister_dev(struct device *, struct request_queue *); int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set); void blk_mq_free_tag_set(struct blk_mq_tag_set *set); void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule); void blk_mq_free_request(struct request *rq); bool blk_mq_queue_inflight(struct request_queue *q); enum { /* return when out of requests */ BLK_MQ_REQ_NOWAIT = (__force blk_mq_req_flags_t)(1 << 0), /* allocate from reserved pool */ BLK_MQ_REQ_RESERVED = (__force blk_mq_req_flags_t)(1 << 1), /* set RQF_PM */ BLK_MQ_REQ_PM = (__force blk_mq_req_flags_t)(1 << 2), }; struct request *blk_mq_alloc_request(struct request_queue *q, unsigned int op, blk_mq_req_flags_t flags); struct request *blk_mq_alloc_request_hctx(struct request_queue *q, unsigned int op, blk_mq_req_flags_t flags, unsigned int hctx_idx); struct request *blk_mq_tag_to_rq(struct blk_mq_tags *tags, unsigned int tag); enum { BLK_MQ_UNIQUE_TAG_BITS = 16, BLK_MQ_UNIQUE_TAG_MASK = (1 << BLK_MQ_UNIQUE_TAG_BITS) - 1, }; u32 blk_mq_unique_tag(struct request *rq); static inline u16 blk_mq_unique_tag_to_hwq(u32 unique_tag) { return unique_tag >> BLK_MQ_UNIQUE_TAG_BITS; } static inline u16 blk_mq_unique_tag_to_tag(u32 unique_tag) { return unique_tag & BLK_MQ_UNIQUE_TAG_MASK; } /** * blk_mq_rq_state() - read the current MQ_RQ_* state of a request * @rq: target request. */ static inline enum mq_rq_state blk_mq_rq_state(struct request *rq) { return READ_ONCE(rq->state); } static inline int blk_mq_request_started(struct request *rq) { return blk_mq_rq_state(rq) != MQ_RQ_IDLE; } static inline int blk_mq_request_completed(struct request *rq) { return blk_mq_rq_state(rq) == MQ_RQ_COMPLETE; } void blk_mq_start_request(struct request *rq); void blk_mq_end_request(struct request *rq, blk_status_t error); void __blk_mq_end_request(struct request *rq, blk_status_t error); void blk_mq_requeue_request(struct request *rq, bool kick_requeue_list); void blk_mq_kick_requeue_list(struct request_queue *q); void blk_mq_delay_kick_requeue_list(struct request_queue *q, unsigned long msecs); void blk_mq_complete_request(struct request *rq); bool blk_mq_complete_request_remote(struct request *rq); bool blk_mq_queue_stopped(struct request_queue *q); void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx); void blk_mq_start_hw_queue(struct blk_mq_hw_ctx *hctx); void blk_mq_stop_hw_queues(struct request_queue *q); void blk_mq_start_hw_queues(struct request_queue *q); void blk_mq_start_stopped_hw_queue(struct blk_mq_hw_ctx *hctx, bool async); void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async); void blk_mq_quiesce_queue(struct request_queue *q); void blk_mq_unquiesce_queue(struct request_queue *q); void blk_mq_delay_run_hw_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs); void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async); void blk_mq_run_hw_queues(struct request_queue *q, bool async); void blk_mq_delay_run_hw_queues(struct request_queue *q, unsigned long msecs); void blk_mq_tagset_busy_iter(struct blk_mq_tag_set *tagset, busy_tag_iter_fn *fn, void *priv); void blk_mq_tagset_wait_completed_request(struct blk_mq_tag_set *tagset); void blk_mq_freeze_queue(struct request_queue *q); void blk_mq_unfreeze_queue(struct request_queue *q); void blk_freeze_queue_start(struct request_queue *q); void blk_mq_freeze_queue_wait(struct request_queue *q); int blk_mq_freeze_queue_wait_timeout(struct request_queue *q, unsigned long timeout); int blk_mq_map_queues(struct blk_mq_queue_map *qmap); void blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, int nr_hw_queues); void blk_mq_quiesce_queue_nowait(struct request_queue *q); unsigned int blk_mq_rq_cpu(struct request *rq); bool __blk_should_fake_timeout(struct request_queue *q); static inline bool blk_should_fake_timeout(struct request_queue *q) { if (IS_ENABLED(CONFIG_FAIL_IO_TIMEOUT) && test_bit(QUEUE_FLAG_FAIL_IO, &q->queue_flags)) return __blk_should_fake_timeout(q); return false; } /** * blk_mq_rq_from_pdu - cast a PDU to a request * @pdu: the PDU (Protocol Data Unit) to be casted * * Return: request * * Driver command data is immediately after the request. So subtract request * size to get back to the original request. */ static inline struct request *blk_mq_rq_from_pdu(void *pdu) { return pdu - sizeof(struct request); } /** * blk_mq_rq_to_pdu - cast a request to a PDU * @rq: the request to be casted * * Return: pointer to the PDU * * Driver command data is immediately after the request. So add request to get * the PDU. */ static inline void *blk_mq_rq_to_pdu(struct request *rq) { return rq + 1; } #define queue_for_each_hw_ctx(q, hctx, i) \ for ((i) = 0; (i) < (q)->nr_hw_queues && \ ({ hctx = (q)->queue_hw_ctx[i]; 1; }); (i)++) #define hctx_for_each_ctx(hctx, ctx, i) \ for ((i) = 0; (i) < (hctx)->nr_ctx && \ ({ ctx = (hctx)->ctxs[(i)]; 1; }); (i)++) static inline blk_qc_t request_to_qc_t(struct blk_mq_hw_ctx *hctx, struct request *rq) { if (rq->tag != -1) return rq->tag | (hctx->queue_num << BLK_QC_T_SHIFT); return rq->internal_tag | (hctx->queue_num << BLK_QC_T_SHIFT) | BLK_QC_T_INTERNAL; } static inline void blk_mq_cleanup_rq(struct request *rq) { if (rq->q->mq_ops->cleanup_rq) rq->q->mq_ops->cleanup_rq(rq); } blk_qc_t blk_mq_submit_bio(struct bio *bio); #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 /* SPDX-License-Identifier: GPL-2.0 */ #ifndef LINUX_MLD_H #define LINUX_MLD_H #include <linux/in6.h> #include <linux/icmpv6.h> /* MLDv1 Query/Report/Done */ struct mld_msg { struct icmp6hdr mld_hdr; struct in6_addr mld_mca; }; #define mld_type mld_hdr.icmp6_type #define mld_code mld_hdr.icmp6_code #define mld_cksum mld_hdr.icmp6_cksum #define mld_maxdelay mld_hdr.icmp6_maxdelay #define mld_reserved mld_hdr.icmp6_dataun.un_data16[1] /* Multicast Listener Discovery version 2 headers */ /* MLDv2 Report */ struct mld2_grec { __u8 grec_type; __u8 grec_auxwords; __be16 grec_nsrcs; struct in6_addr grec_mca; struct in6_addr grec_src[]; }; struct mld2_report { struct icmp6hdr mld2r_hdr; struct mld2_grec mld2r_grec[]; }; #define mld2r_type mld2r_hdr.icmp6_type #define mld2r_resv1 mld2r_hdr.icmp6_code #define mld2r_cksum mld2r_hdr.icmp6_cksum #define mld2r_resv2 mld2r_hdr.icmp6_dataun.un_data16[0] #define mld2r_ngrec mld2r_hdr.icmp6_dataun.un_data16[1] /* MLDv2 Query */ struct mld2_query { struct icmp6hdr mld2q_hdr; struct in6_addr mld2q_mca; #if defined(__LITTLE_ENDIAN_BITFIELD) __u8 mld2q_qrv:3, mld2q_suppress:1, mld2q_resv2:4; #elif defined(__BIG_ENDIAN_BITFIELD) __u8 mld2q_resv2:4, mld2q_suppress:1, mld2q_qrv:3; #else #error "Please fix <asm/byteorder.h>" #endif __u8 mld2q_qqic; __be16 mld2q_nsrcs; struct in6_addr mld2q_srcs[]; }; #define mld2q_type mld2q_hdr.icmp6_type #define mld2q_code mld2q_hdr.icmp6_code #define mld2q_cksum mld2q_hdr.icmp6_cksum #define mld2q_mrc mld2q_hdr.icmp6_maxdelay #define mld2q_resv1 mld2q_hdr.icmp6_dataun.un_data16[1] /* RFC3810, 5.1.3. Maximum Response Code: * * If Maximum Response Code >= 32768, Maximum Response Code represents a * floating-point value as follows: * * 0 1 2 3 4 5 6 7 8 9 A B C D E F * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ * |1| exp | mant | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ */ #define MLDV2_MRC_EXP(value) (((value) >> 12) & 0x0007) #define MLDV2_MRC_MAN(value) ((value) & 0x0fff) /* RFC3810, 5.1.9. QQIC (Querier's Query Interval Code): * * If QQIC >= 128, QQIC represents a floating-point value as follows: * * 0 1 2 3 4 5 6 7 * +-+-+-+-+-+-+-+-+ * |1| exp | mant | * +-+-+-+-+-+-+-+-+ */ #define MLDV2_QQIC_EXP(value) (((value) >> 4) & 0x07) #define MLDV2_QQIC_MAN(value) ((value) & 0x0f) #define MLD_EXP_MIN_LIMIT 32768UL #define MLDV1_MRD_MAX_COMPAT (MLD_EXP_MIN_LIMIT - 1) static inline unsigned long mldv2_mrc(const struct mld2_query *mlh2) { /* RFC3810, 5.1.3. Maximum Response Code */ unsigned long ret, mc_mrc = ntohs(mlh2->mld2q_mrc); if (mc_mrc < MLD_EXP_MIN_LIMIT) { ret = mc_mrc; } else { unsigned long mc_man, mc_exp; mc_exp = MLDV2_MRC_EXP(mc_mrc); mc_man = MLDV2_MRC_MAN(mc_mrc); ret = (mc_man | 0x1000) << (mc_exp + 3); } return ret; } #endif
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2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 /* SPDX-License-Identifier: GPL-2.0-or-later */ /* * Copyright 2003-2005 Red Hat, Inc. All rights reserved. * Copyright 2003-2005 Jeff Garzik * * libata documentation is available via 'make {ps|pdf}docs', * as Documentation/driver-api/libata.rst */ #ifndef __LINUX_LIBATA_H__ #define __LINUX_LIBATA_H__ #include <linux/delay.h> #include <linux/jiffies.h> #include <linux/interrupt.h> #include <linux/dma-mapping.h> #include <linux/scatterlist.h> #include <linux/io.h> #include <linux/ata.h> #include <linux/workqueue.h> #include <scsi/scsi_host.h> #include <linux/acpi.h> #include <linux/cdrom.h> #include <linux/sched.h> #include <linux/async.h> /* * Define if arch has non-standard setup. This is a _PCI_ standard * not a legacy or ISA standard. */ #ifdef CONFIG_ATA_NONSTANDARD #include <asm/libata-portmap.h> #else #define ATA_PRIMARY_IRQ(dev) 14 #define ATA_SECONDARY_IRQ(dev) 15 #endif /* * compile-time options: to be removed as soon as all the drivers are * converted to the new debugging mechanism */ #undef ATA_DEBUG /* debugging output */ #undef ATA_VERBOSE_DEBUG /* yet more debugging output */ #undef ATA_IRQ_TRAP /* define to ack screaming irqs */ #undef ATA_NDEBUG /* define to disable quick runtime checks */ /* note: prints function name for you */ #ifdef ATA_DEBUG #define DPRINTK(fmt, args...) printk(KERN_ERR "%s: " fmt, __func__, ## args) #ifdef ATA_VERBOSE_DEBUG #define VPRINTK(fmt, args...) printk(KERN_ERR "%s: " fmt, __func__, ## args) #else #define VPRINTK(fmt, args...) #endif /* ATA_VERBOSE_DEBUG */ #else #define DPRINTK(fmt, args...) #define VPRINTK(fmt, args...) #endif /* ATA_DEBUG */ #define ata_print_version_once(dev, version) \ ({ \ static bool __print_once; \ \ if (!__print_once) { \ __print_once = true; \ ata_print_version(dev, version); \ } \ }) /* NEW: debug levels */ #define HAVE_LIBATA_MSG 1 enum { ATA_MSG_DRV = 0x0001, ATA_MSG_INFO = 0x0002, ATA_MSG_PROBE = 0x0004, ATA_MSG_WARN = 0x0008, ATA_MSG_MALLOC = 0x0010, ATA_MSG_CTL = 0x0020, ATA_MSG_INTR = 0x0040, ATA_MSG_ERR = 0x0080, }; #define ata_msg_drv(p) ((p)->msg_enable & ATA_MSG_DRV) #define ata_msg_info(p) ((p)->msg_enable & ATA_MSG_INFO) #define ata_msg_probe(p) ((p)->msg_enable & ATA_MSG_PROBE) #define ata_msg_warn(p) ((p)->msg_enable & ATA_MSG_WARN) #define ata_msg_malloc(p) ((p)->msg_enable & ATA_MSG_MALLOC) #define ata_msg_ctl(p) ((p)->msg_enable & ATA_MSG_CTL) #define ata_msg_intr(p) ((p)->msg_enable & ATA_MSG_INTR) #define ata_msg_err(p) ((p)->msg_enable & ATA_MSG_ERR) static inline u32 ata_msg_init(int dval, int default_msg_enable_bits) { if (dval < 0 || dval >= (sizeof(u32) * 8)) return default_msg_enable_bits; /* should be 0x1 - only driver info msgs */ if (!dval) return 0; return (1 << dval) - 1; } /* defines only for the constants which don't work well as enums */ #define ATA_TAG_POISON 0xfafbfcfdU enum { /* various global constants */ LIBATA_MAX_PRD = ATA_MAX_PRD / 2, LIBATA_DUMB_MAX_PRD = ATA_MAX_PRD / 4, /* Worst case */ ATA_DEF_QUEUE = 1, ATA_MAX_QUEUE = 32, ATA_TAG_INTERNAL = ATA_MAX_QUEUE, ATA_SHORT_PAUSE = 16, ATAPI_MAX_DRAIN = 16 << 10, ATA_ALL_DEVICES = (1 << ATA_MAX_DEVICES) - 1, ATA_SHT_EMULATED = 1, ATA_SHT_THIS_ID = -1, /* struct ata_taskfile flags */ ATA_TFLAG_LBA48 = (1 << 0), /* enable 48-bit LBA and "HOB" */ ATA_TFLAG_ISADDR = (1 << 1), /* enable r/w to nsect/lba regs */ ATA_TFLAG_DEVICE = (1 << 2), /* enable r/w to device reg */ ATA_TFLAG_WRITE = (1 << 3), /* data dir: host->dev==1 (write) */ ATA_TFLAG_LBA = (1 << 4), /* enable LBA */ ATA_TFLAG_FUA = (1 << 5), /* enable FUA */ ATA_TFLAG_POLLING = (1 << 6), /* set nIEN to 1 and use polling */ /* struct ata_device stuff */ ATA_DFLAG_LBA = (1 << 0), /* device supports LBA */ ATA_DFLAG_LBA48 = (1 << 1), /* device supports LBA48 */ ATA_DFLAG_CDB_INTR = (1 << 2), /* device asserts INTRQ when ready for CDB */ ATA_DFLAG_NCQ = (1 << 3), /* device supports NCQ */ ATA_DFLAG_FLUSH_EXT = (1 << 4), /* do FLUSH_EXT instead of FLUSH */ ATA_DFLAG_ACPI_PENDING = (1 << 5), /* ACPI resume action pending */ ATA_DFLAG_ACPI_FAILED = (1 << 6), /* ACPI on devcfg has failed */ ATA_DFLAG_AN = (1 << 7), /* AN configured */ ATA_DFLAG_TRUSTED = (1 << 8), /* device supports trusted send/recv */ ATA_DFLAG_DMADIR = (1 << 10), /* device requires DMADIR */ ATA_DFLAG_CFG_MASK = (1 << 12) - 1, ATA_DFLAG_PIO = (1 << 12), /* device limited to PIO mode */ ATA_DFLAG_NCQ_OFF = (1 << 13), /* device limited to non-NCQ mode */ ATA_DFLAG_SLEEPING = (1 << 15), /* device is sleeping */ ATA_DFLAG_DUBIOUS_XFER = (1 << 16), /* data transfer not verified */ ATA_DFLAG_NO_UNLOAD = (1 << 17), /* device doesn't support unload */ ATA_DFLAG_UNLOCK_HPA = (1 << 18), /* unlock HPA */ ATA_DFLAG_NCQ_SEND_RECV = (1 << 19), /* device supports NCQ SEND and RECV */ ATA_DFLAG_NCQ_PRIO = (1 << 20), /* device supports NCQ priority */ ATA_DFLAG_NCQ_PRIO_ENABLE = (1 << 21), /* Priority cmds sent to dev */ ATA_DFLAG_INIT_MASK = (1 << 24) - 1, ATA_DFLAG_DETACH = (1 << 24), ATA_DFLAG_DETACHED = (1 << 25), ATA_DFLAG_DA = (1 << 26), /* device supports Device Attention */ ATA_DFLAG_DEVSLP = (1 << 27), /* device supports Device Sleep */ ATA_DFLAG_ACPI_DISABLED = (1 << 28), /* ACPI for the device is disabled */ ATA_DFLAG_D_SENSE = (1 << 29), /* Descriptor sense requested */ ATA_DFLAG_ZAC = (1 << 30), /* ZAC device */ ATA_DEV_UNKNOWN = 0, /* unknown device */ ATA_DEV_ATA = 1, /* ATA device */ ATA_DEV_ATA_UNSUP = 2, /* ATA device (unsupported) */ ATA_DEV_ATAPI = 3, /* ATAPI device */ ATA_DEV_ATAPI_UNSUP = 4, /* ATAPI device (unsupported) */ ATA_DEV_PMP = 5, /* SATA port multiplier */ ATA_DEV_PMP_UNSUP = 6, /* SATA port multiplier (unsupported) */ ATA_DEV_SEMB = 7, /* SEMB */ ATA_DEV_SEMB_UNSUP = 8, /* SEMB (unsupported) */ ATA_DEV_ZAC = 9, /* ZAC device */ ATA_DEV_ZAC_UNSUP = 10, /* ZAC device (unsupported) */ ATA_DEV_NONE = 11, /* no device */ /* struct ata_link flags */ /* NOTE: struct ata_force_param currently stores lflags in u16 */ ATA_LFLAG_NO_HRST = (1 << 1), /* avoid hardreset */ ATA_LFLAG_NO_SRST = (1 << 2), /* avoid softreset */ ATA_LFLAG_ASSUME_ATA = (1 << 3), /* assume ATA class */ ATA_LFLAG_ASSUME_SEMB = (1 << 4), /* assume SEMB class */ ATA_LFLAG_ASSUME_CLASS = ATA_LFLAG_ASSUME_ATA | ATA_LFLAG_ASSUME_SEMB, ATA_LFLAG_NO_RETRY = (1 << 5), /* don't retry this link */ ATA_LFLAG_DISABLED = (1 << 6), /* link is disabled */ ATA_LFLAG_SW_ACTIVITY = (1 << 7), /* keep activity stats */ ATA_LFLAG_NO_LPM = (1 << 8), /* disable LPM on this link */ ATA_LFLAG_RST_ONCE = (1 << 9), /* limit recovery to one reset */ ATA_LFLAG_CHANGED = (1 << 10), /* LPM state changed on this link */ ATA_LFLAG_NO_DB_DELAY = (1 << 11), /* no debounce delay on link resume */ /* struct ata_port flags */ ATA_FLAG_SLAVE_POSS = (1 << 0), /* host supports slave dev */ /* (doesn't imply presence) */ ATA_FLAG_SATA = (1 << 1), ATA_FLAG_NO_LPM = (1 << 2), /* host not happy with LPM */ ATA_FLAG_NO_LOG_PAGE = (1 << 5), /* do not issue log page read */ ATA_FLAG_NO_ATAPI = (1 << 6), /* No ATAPI support */ ATA_FLAG_PIO_DMA = (1 << 7), /* PIO cmds via DMA */ ATA_FLAG_PIO_LBA48 = (1 << 8), /* Host DMA engine is LBA28 only */ ATA_FLAG_PIO_POLLING = (1 << 9), /* use polling PIO if LLD * doesn't handle PIO interrupts */ ATA_FLAG_NCQ = (1 << 10), /* host supports NCQ */ ATA_FLAG_NO_POWEROFF_SPINDOWN = (1 << 11), /* don't spindown before poweroff */ ATA_FLAG_NO_HIBERNATE_SPINDOWN = (1 << 12), /* don't spindown before hibernation */ ATA_FLAG_DEBUGMSG = (1 << 13), ATA_FLAG_FPDMA_AA = (1 << 14), /* driver supports Auto-Activate */ ATA_FLAG_IGN_SIMPLEX = (1 << 15), /* ignore SIMPLEX */ ATA_FLAG_NO_IORDY = (1 << 16), /* controller lacks iordy */ ATA_FLAG_ACPI_SATA = (1 << 17), /* need native SATA ACPI layout */ ATA_FLAG_AN = (1 << 18), /* controller supports AN */ ATA_FLAG_PMP = (1 << 19), /* controller supports PMP */ ATA_FLAG_FPDMA_AUX = (1 << 20), /* controller supports H2DFIS aux field */ ATA_FLAG_EM = (1 << 21), /* driver supports enclosure * management */ ATA_FLAG_SW_ACTIVITY = (1 << 22), /* driver supports sw activity * led */ ATA_FLAG_NO_DIPM = (1 << 23), /* host not happy with DIPM */ ATA_FLAG_SAS_HOST = (1 << 24), /* SAS host */ /* bits 24:31 of ap->flags are reserved for LLD specific flags */ /* struct ata_port pflags */ ATA_PFLAG_EH_PENDING = (1 << 0), /* EH pending */ ATA_PFLAG_EH_IN_PROGRESS = (1 << 1), /* EH in progress */ ATA_PFLAG_FROZEN = (1 << 2), /* port is frozen */ ATA_PFLAG_RECOVERED = (1 << 3), /* recovery action performed */ ATA_PFLAG_LOADING = (1 << 4), /* boot/loading probe */ ATA_PFLAG_SCSI_HOTPLUG = (1 << 6), /* SCSI hotplug scheduled */ ATA_PFLAG_INITIALIZING = (1 << 7), /* being initialized, don't touch */ ATA_PFLAG_RESETTING = (1 << 8), /* reset in progress */ ATA_PFLAG_UNLOADING = (1 << 9), /* driver is being unloaded */ ATA_PFLAG_UNLOADED = (1 << 10), /* driver is unloaded */ ATA_PFLAG_SUSPENDED = (1 << 17), /* port is suspended (power) */ ATA_PFLAG_PM_PENDING = (1 << 18), /* PM operation pending */ ATA_PFLAG_INIT_GTM_VALID = (1 << 19), /* initial gtm data valid */ ATA_PFLAG_PIO32 = (1 << 20), /* 32bit PIO */ ATA_PFLAG_PIO32CHANGE = (1 << 21), /* 32bit PIO can be turned on/off */ ATA_PFLAG_EXTERNAL = (1 << 22), /* eSATA/external port */ /* struct ata_queued_cmd flags */ ATA_QCFLAG_ACTIVE = (1 << 0), /* cmd not yet ack'd to scsi lyer */ ATA_QCFLAG_DMAMAP = (1 << 1), /* SG table is DMA mapped */ ATA_QCFLAG_IO = (1 << 3), /* standard IO command */ ATA_QCFLAG_RESULT_TF = (1 << 4), /* result TF requested */ ATA_QCFLAG_CLEAR_EXCL = (1 << 5), /* clear excl_link on completion */ ATA_QCFLAG_QUIET = (1 << 6), /* don't report device error */ ATA_QCFLAG_RETRY = (1 << 7), /* retry after failure */ ATA_QCFLAG_FAILED = (1 << 16), /* cmd failed and is owned by EH */ ATA_QCFLAG_SENSE_VALID = (1 << 17), /* sense data valid */ ATA_QCFLAG_EH_SCHEDULED = (1 << 18), /* EH scheduled (obsolete) */ /* host set flags */ ATA_HOST_SIMPLEX = (1 << 0), /* Host is simplex, one DMA channel per host only */ ATA_HOST_STARTED = (1 << 1), /* Host started */ ATA_HOST_PARALLEL_SCAN = (1 << 2), /* Ports on this host can be scanned in parallel */ ATA_HOST_IGNORE_ATA = (1 << 3), /* Ignore ATA devices on this host. */ /* bits 24:31 of host->flags are reserved for LLD specific flags */ /* various lengths of time */ ATA_TMOUT_BOOT = 30000, /* heuristic */ ATA_TMOUT_BOOT_QUICK = 7000, /* heuristic */ ATA_TMOUT_INTERNAL_QUICK = 5000, ATA_TMOUT_MAX_PARK = 30000, /* * GoVault needs 2s and iVDR disk HHD424020F7SV00 800ms. 2s * is too much without parallel probing. Use 2s if parallel * probing is available, 800ms otherwise. */ ATA_TMOUT_FF_WAIT_LONG = 2000, ATA_TMOUT_FF_WAIT = 800, /* Spec mandates to wait for ">= 2ms" before checking status * after reset. We wait 150ms, because that was the magic * delay used for ATAPI devices in Hale Landis's ATADRVR, for * the period of time between when the ATA command register is * written, and then status is checked. Because waiting for * "a while" before checking status is fine, post SRST, we * perform this magic delay here as well. * * Old drivers/ide uses the 2mS rule and then waits for ready. */ ATA_WAIT_AFTER_RESET = 150, /* If PMP is supported, we have to do follow-up SRST. As some * PMPs don't send D2H Reg FIS after hardreset, LLDs are * advised to wait only for the following duration before * doing SRST. */ ATA_TMOUT_PMP_SRST_WAIT = 5000, /* When the LPM policy is set to ATA_LPM_MAX_POWER, there might * be a spurious PHY event, so ignore the first PHY event that * occurs within 10s after the policy change. */ ATA_TMOUT_SPURIOUS_PHY = 10000, /* ATA bus states */ BUS_UNKNOWN = 0, BUS_DMA = 1, BUS_IDLE = 2, BUS_NOINTR = 3, BUS_NODATA = 4, BUS_TIMER = 5, BUS_PIO = 6, BUS_EDD = 7, BUS_IDENTIFY = 8, BUS_PACKET = 9, /* SATA port states */ PORT_UNKNOWN = 0, PORT_ENABLED = 1, PORT_DISABLED = 2, /* encoding various smaller bitmaps into a single * unsigned long bitmap */ ATA_NR_PIO_MODES = 7, ATA_NR_MWDMA_MODES = 5, ATA_NR_UDMA_MODES = 8, ATA_SHIFT_PIO = 0, ATA_SHIFT_MWDMA = ATA_SHIFT_PIO + ATA_NR_PIO_MODES, ATA_SHIFT_UDMA = ATA_SHIFT_MWDMA + ATA_NR_MWDMA_MODES, ATA_SHIFT_PRIO = 6, ATA_PRIO_HIGH = 2, /* size of buffer to pad xfers ending on unaligned boundaries */ ATA_DMA_PAD_SZ = 4, /* ering size */ ATA_ERING_SIZE = 32, /* return values for ->qc_defer */ ATA_DEFER_LINK = 1, ATA_DEFER_PORT = 2, /* desc_len for ata_eh_info and context */ ATA_EH_DESC_LEN = 80, /* reset / recovery action types */ ATA_EH_REVALIDATE = (1 << 0), ATA_EH_SOFTRESET = (1 << 1), /* meaningful only in ->prereset */ ATA_EH_HARDRESET = (1 << 2), /* meaningful only in ->prereset */ ATA_EH_RESET = ATA_EH_SOFTRESET | ATA_EH_HARDRESET, ATA_EH_ENABLE_LINK = (1 << 3), ATA_EH_PARK = (1 << 5), /* unload heads and stop I/O */ ATA_EH_PERDEV_MASK = ATA_EH_REVALIDATE | ATA_EH_PARK, ATA_EH_ALL_ACTIONS = ATA_EH_REVALIDATE | ATA_EH_RESET | ATA_EH_ENABLE_LINK, /* ata_eh_info->flags */ ATA_EHI_HOTPLUGGED = (1 << 0), /* could have been hotplugged */ ATA_EHI_NO_AUTOPSY = (1 << 2), /* no autopsy */ ATA_EHI_QUIET = (1 << 3), /* be quiet */ ATA_EHI_NO_RECOVERY = (1 << 4), /* no recovery */ ATA_EHI_DID_SOFTRESET = (1 << 16), /* already soft-reset this port */ ATA_EHI_DID_HARDRESET = (1 << 17), /* already soft-reset this port */ ATA_EHI_PRINTINFO = (1 << 18), /* print configuration info */ ATA_EHI_SETMODE = (1 << 19), /* configure transfer mode */ ATA_EHI_POST_SETMODE = (1 << 20), /* revalidating after setmode */ ATA_EHI_DID_RESET = ATA_EHI_DID_SOFTRESET | ATA_EHI_DID_HARDRESET, /* mask of flags to transfer *to* the slave link */ ATA_EHI_TO_SLAVE_MASK = ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET, /* max tries if error condition is still set after ->error_handler */ ATA_EH_MAX_TRIES = 5, /* sometimes resuming a link requires several retries */ ATA_LINK_RESUME_TRIES = 5, /* how hard are we gonna try to probe/recover devices */ ATA_PROBE_MAX_TRIES = 3, ATA_EH_DEV_TRIES = 3, ATA_EH_PMP_TRIES = 5, ATA_EH_PMP_LINK_TRIES = 3, SATA_PMP_RW_TIMEOUT = 3000, /* PMP read/write timeout */ /* This should match the actual table size of * ata_eh_cmd_timeout_table in libata-eh.c. */ ATA_EH_CMD_TIMEOUT_TABLE_SIZE = 7, /* Horkage types. May be set by libata or controller on drives (some horkage may be drive/controller pair dependent */ ATA_HORKAGE_DIAGNOSTIC = (1 << 0), /* Failed boot diag */ ATA_HORKAGE_NODMA = (1 << 1), /* DMA problems */ ATA_HORKAGE_NONCQ = (1 << 2), /* Don't use NCQ */ ATA_HORKAGE_MAX_SEC_128 = (1 << 3), /* Limit max sects to 128 */ ATA_HORKAGE_BROKEN_HPA = (1 << 4), /* Broken HPA */ ATA_HORKAGE_DISABLE = (1 << 5), /* Disable it */ ATA_HORKAGE_HPA_SIZE = (1 << 6), /* native size off by one */ ATA_HORKAGE_IVB = (1 << 8), /* cbl det validity bit bugs */ ATA_HORKAGE_STUCK_ERR = (1 << 9), /* stuck ERR on next PACKET */ ATA_HORKAGE_BRIDGE_OK = (1 << 10), /* no bridge limits */ ATA_HORKAGE_ATAPI_MOD16_DMA = (1 << 11), /* use ATAPI DMA for commands not multiple of 16 bytes */ ATA_HORKAGE_FIRMWARE_WARN = (1 << 12), /* firmware update warning */ ATA_HORKAGE_1_5_GBPS = (1 << 13), /* force 1.5 Gbps */ ATA_HORKAGE_NOSETXFER = (1 << 14), /* skip SETXFER, SATA only */ ATA_HORKAGE_BROKEN_FPDMA_AA = (1 << 15), /* skip AA */ ATA_HORKAGE_DUMP_ID = (1 << 16), /* dump IDENTIFY data */ ATA_HORKAGE_MAX_SEC_LBA48 = (1 << 17), /* Set max sects to 65535 */ ATA_HORKAGE_ATAPI_DMADIR = (1 << 18), /* device requires dmadir */ ATA_HORKAGE_NO_NCQ_TRIM = (1 << 19), /* don't use queued TRIM */ ATA_HORKAGE_NOLPM = (1 << 20), /* don't use LPM */ ATA_HORKAGE_WD_BROKEN_LPM = (1 << 21), /* some WDs have broken LPM */ ATA_HORKAGE_ZERO_AFTER_TRIM = (1 << 22),/* guarantees zero after trim */ ATA_HORKAGE_NO_DMA_LOG = (1 << 23), /* don't use DMA for log read */ ATA_HORKAGE_NOTRIM = (1 << 24), /* don't use TRIM */ ATA_HORKAGE_MAX_SEC_1024 = (1 << 25), /* Limit max sects to 1024 */ ATA_HORKAGE_MAX_TRIM_128M = (1 << 26), /* Limit max trim size to 128M */ ATA_HORKAGE_NO_NCQ_ON_ATI = (1 << 27), /* Disable NCQ on ATI chipset */ /* DMA mask for user DMA control: User visible values; DO NOT renumber */ ATA_DMA_MASK_ATA = (1 << 0), /* DMA on ATA Disk */ ATA_DMA_MASK_ATAPI = (1 << 1), /* DMA on ATAPI */ ATA_DMA_MASK_CFA = (1 << 2), /* DMA on CF Card */ /* ATAPI command types */ ATAPI_READ = 0, /* READs */ ATAPI_WRITE = 1, /* WRITEs */ ATAPI_READ_CD = 2, /* READ CD [MSF] */ ATAPI_PASS_THRU = 3, /* SAT pass-thru */ ATAPI_MISC = 4, /* the rest */ /* Timing constants */ ATA_TIMING_SETUP = (1 << 0), ATA_TIMING_ACT8B = (1 << 1), ATA_TIMING_REC8B = (1 << 2), ATA_TIMING_CYC8B = (1 << 3), ATA_TIMING_8BIT = ATA_TIMING_ACT8B | ATA_TIMING_REC8B | ATA_TIMING_CYC8B, ATA_TIMING_ACTIVE = (1 << 4), ATA_TIMING_RECOVER = (1 << 5), ATA_TIMING_DMACK_HOLD = (1 << 6), ATA_TIMING_CYCLE = (1 << 7), ATA_TIMING_UDMA = (1 << 8), ATA_TIMING_ALL = ATA_TIMING_SETUP | ATA_TIMING_ACT8B | ATA_TIMING_REC8B | ATA_TIMING_CYC8B | ATA_TIMING_ACTIVE | ATA_TIMING_RECOVER | ATA_TIMING_DMACK_HOLD | ATA_TIMING_CYCLE | ATA_TIMING_UDMA, /* ACPI constants */ ATA_ACPI_FILTER_SETXFER = 1 << 0, ATA_ACPI_FILTER_LOCK = 1 << 1, ATA_ACPI_FILTER_DIPM = 1 << 2, ATA_ACPI_FILTER_FPDMA_OFFSET = 1 << 3, /* FPDMA non-zero offset */ ATA_ACPI_FILTER_FPDMA_AA = 1 << 4, /* FPDMA auto activate */ ATA_ACPI_FILTER_DEFAULT = ATA_ACPI_FILTER_SETXFER | ATA_ACPI_FILTER_LOCK | ATA_ACPI_FILTER_DIPM, }; enum ata_xfer_mask { ATA_MASK_PIO = ((1LU << ATA_NR_PIO_MODES) - 1) << ATA_SHIFT_PIO, ATA_MASK_MWDMA = ((1LU << ATA_NR_MWDMA_MODES) - 1) << ATA_SHIFT_MWDMA, ATA_MASK_UDMA = ((1LU << ATA_NR_UDMA_MODES) - 1) << ATA_SHIFT_UDMA, }; enum hsm_task_states { HSM_ST_IDLE, /* no command on going */ HSM_ST_FIRST, /* (waiting the device to) write CDB or first data block */ HSM_ST, /* (waiting the device to) transfer data */ HSM_ST_LAST, /* (waiting the device to) complete command */ HSM_ST_ERR, /* error */ }; enum ata_completion_errors { AC_ERR_OK = 0, /* no error */ AC_ERR_DEV = (1 << 0), /* device reported error */ AC_ERR_HSM = (1 << 1), /* host state machine violation */ AC_ERR_TIMEOUT = (1 << 2), /* timeout */ AC_ERR_MEDIA = (1 << 3), /* media error */ AC_ERR_ATA_BUS = (1 << 4), /* ATA bus error */ AC_ERR_HOST_BUS = (1 << 5), /* host bus error */ AC_ERR_SYSTEM = (1 << 6), /* system error */ AC_ERR_INVALID = (1 << 7), /* invalid argument */ AC_ERR_OTHER = (1 << 8), /* unknown */ AC_ERR_NODEV_HINT = (1 << 9), /* polling device detection hint */ AC_ERR_NCQ = (1 << 10), /* marker for offending NCQ qc */ }; /* * Link power management policy: If you alter this, you also need to * alter libata-scsi.c (for the ascii descriptions) */ enum ata_lpm_policy { ATA_LPM_UNKNOWN, ATA_LPM_MAX_POWER, ATA_LPM_MED_POWER, ATA_LPM_MED_POWER_WITH_DIPM, /* Med power + DIPM as win IRST does */ ATA_LPM_MIN_POWER_WITH_PARTIAL, /* Min Power + partial and slumber */ ATA_LPM_MIN_POWER, /* Min power + no partial (slumber only) */ }; enum ata_lpm_hints { ATA_LPM_EMPTY = (1 << 0), /* port empty/probing */ ATA_LPM_HIPM = (1 << 1), /* may use HIPM */ ATA_LPM_WAKE_ONLY = (1 << 2), /* only wake up link */ }; /* forward declarations */ struct scsi_device; struct ata_port_operations; struct ata_port; struct ata_link; struct ata_queued_cmd; /* typedefs */ typedef void (*ata_qc_cb_t) (struct ata_queued_cmd *qc); typedef int (*ata_prereset_fn_t)(struct ata_link *link, unsigned long deadline); typedef int (*ata_reset_fn_t)(struct ata_link *link, unsigned int *classes, unsigned long deadline); typedef void (*ata_postreset_fn_t)(struct ata_link *link, unsigned int *classes); extern struct device_attribute dev_attr_unload_heads; #ifdef CONFIG_SATA_HOST extern struct device_attribute dev_attr_link_power_management_policy; extern struct device_attribute dev_attr_ncq_prio_enable; extern struct device_attribute dev_attr_em_message_type; extern struct device_attribute dev_attr_em_message; extern struct device_attribute dev_attr_sw_activity; #endif enum sw_activity { OFF, BLINK_ON, BLINK_OFF, }; struct ata_taskfile { unsigned long flags; /* ATA_TFLAG_xxx */ u8 protocol; /* ATA_PROT_xxx */ u8 ctl; /* control reg */ u8 hob_feature; /* additional data */ u8 hob_nsect; /* to support LBA48 */ u8 hob_lbal; u8 hob_lbam; u8 hob_lbah; u8 feature; u8 nsect; u8 lbal; u8 lbam; u8 lbah; u8 device; u8 command; /* IO operation */ u32 auxiliary; /* auxiliary field */ /* from SATA 3.1 and */ /* ATA-8 ACS-3 */ }; #ifdef CONFIG_ATA_SFF struct ata_ioports { void __iomem *cmd_addr; void __iomem *data_addr; void __iomem *error_addr; void __iomem *feature_addr; void __iomem *nsect_addr; void __iomem *lbal_addr; void __iomem *lbam_addr; void __iomem *lbah_addr; void __iomem *device_addr; void __iomem *status_addr; void __iomem *command_addr; void __iomem *altstatus_addr; void __iomem *ctl_addr; #ifdef CONFIG_ATA_BMDMA void __iomem *bmdma_addr; #endif /* CONFIG_ATA_BMDMA */ void __iomem *scr_addr; }; #endif /* CONFIG_ATA_SFF */ struct ata_host { spinlock_t lock; struct device *dev; void __iomem * const *iomap; unsigned int n_ports; unsigned int n_tags; /* nr of NCQ tags */ void *private_data; struct ata_port_operations *ops; unsigned long flags; struct kref kref; struct mutex eh_mutex; struct task_struct *eh_owner; struct ata_port *simplex_claimed; /* channel owning the DMA */ struct ata_port *ports[]; }; struct ata_queued_cmd { struct ata_port *ap; struct ata_device *dev; struct scsi_cmnd *scsicmd; void (*scsidone)(struct scsi_cmnd *); struct ata_taskfile tf; u8 cdb[ATAPI_CDB_LEN]; unsigned long flags; /* ATA_QCFLAG_xxx */ unsigned int tag; /* libata core tag */ unsigned int hw_tag; /* driver tag */ unsigned int n_elem; unsigned int orig_n_elem; int dma_dir; unsigned int sect_size; unsigned int nbytes; unsigned int extrabytes; unsigned int curbytes; struct scatterlist sgent; struct scatterlist *sg; struct scatterlist *cursg; unsigned int cursg_ofs; unsigned int err_mask; struct ata_taskfile result_tf; ata_qc_cb_t complete_fn; void *private_data; void *lldd_task; }; struct ata_port_stats { unsigned long unhandled_irq; unsigned long idle_irq; unsigned long rw_reqbuf; }; struct ata_ering_entry { unsigned int eflags; unsigned int err_mask; u64 timestamp; }; struct ata_ering { int cursor; struct ata_ering_entry ring[ATA_ERING_SIZE]; }; struct ata_device { struct ata_link *link; unsigned int devno; /* 0 or 1 */ unsigned int horkage; /* List of broken features */ unsigned long flags; /* ATA_DFLAG_xxx */ struct scsi_device *sdev; /* attached SCSI device */ void *private_data; #ifdef CONFIG_ATA_ACPI union acpi_object *gtf_cache; unsigned int gtf_filter; #endif #ifdef CONFIG_SATA_ZPODD void *zpodd; #endif struct device tdev; /* n_sector is CLEAR_BEGIN, read comment above CLEAR_BEGIN */ u64 n_sectors; /* size of device, if ATA */ u64 n_native_sectors; /* native size, if ATA */ unsigned int class; /* ATA_DEV_xxx */ unsigned long unpark_deadline; u8 pio_mode; u8 dma_mode; u8 xfer_mode; unsigned int xfer_shift; /* ATA_SHIFT_xxx */ unsigned int multi_count; /* sectors count for READ/WRITE MULTIPLE */ unsigned int max_sectors; /* per-device max sectors */ unsigned int cdb_len; /* per-dev xfer mask */ unsigned long pio_mask; unsigned long mwdma_mask; unsigned long udma_mask; /* for CHS addressing */ u16 cylinders; /* Number of cylinders */ u16 heads; /* Number of heads */ u16 sectors; /* Number of sectors per track */ union { u16 id[ATA_ID_WORDS]; /* IDENTIFY xxx DEVICE data */ u32 gscr[SATA_PMP_GSCR_DWORDS]; /* PMP GSCR block */ } ____cacheline_aligned; /* DEVSLP Timing Variables from Identify Device Data Log */ u8 devslp_timing[ATA_LOG_DEVSLP_SIZE]; /* NCQ send and receive log subcommand support */ u8 ncq_send_recv_cmds[ATA_LOG_NCQ_SEND_RECV_SIZE]; u8 ncq_non_data_cmds[ATA_LOG_NCQ_NON_DATA_SIZE]; /* ZAC zone configuration */ u32 zac_zoned_cap; u32 zac_zones_optimal_open; u32 zac_zones_optimal_nonseq; u32 zac_zones_max_open; /* error history */ int spdn_cnt; /* ering is CLEAR_END, read comment above CLEAR_END */ struct ata_ering ering; }; /* Fields between ATA_DEVICE_CLEAR_BEGIN and ATA_DEVICE_CLEAR_END are * cleared to zero on ata_dev_init(). */ #define ATA_DEVICE_CLEAR_BEGIN offsetof(struct ata_device, n_sectors) #define ATA_DEVICE_CLEAR_END offsetof(struct ata_device, ering) struct ata_eh_info { struct ata_device *dev; /* offending device */ u32 serror; /* SError from LLDD */ unsigned int err_mask; /* port-wide err_mask */ unsigned int action; /* ATA_EH_* action mask */ unsigned int dev_action[ATA_MAX_DEVICES]; /* dev EH action */ unsigned int flags; /* ATA_EHI_* flags */ unsigned int probe_mask; char desc[ATA_EH_DESC_LEN]; int desc_len; }; struct ata_eh_context { struct ata_eh_info i; int tries[ATA_MAX_DEVICES]; int cmd_timeout_idx[ATA_MAX_DEVICES] [ATA_EH_CMD_TIMEOUT_TABLE_SIZE]; unsigned int classes[ATA_MAX_DEVICES]; unsigned int did_probe_mask; unsigned int unloaded_mask; unsigned int saved_ncq_enabled; u8 saved_xfer_mode[ATA_MAX_DEVICES]; /* timestamp for the last reset attempt or success */ unsigned long last_reset; }; struct ata_acpi_drive { u32 pio; u32 dma; } __packed; struct ata_acpi_gtm { struct ata_acpi_drive drive[2]; u32 flags; } __packed; struct ata_link { struct ata_port *ap; int pmp; /* port multiplier port # */ struct device tdev; unsigned int active_tag; /* active tag on this link */ u32 sactive; /* active NCQ commands */ unsigned int flags; /* ATA_LFLAG_xxx */ u32 saved_scontrol; /* SControl on probe */ unsigned int hw_sata_spd_limit; unsigned int sata_spd_limit; unsigned int sata_spd; /* current SATA PHY speed */ enum ata_lpm_policy lpm_policy; /* record runtime error info, protected by host_set lock */ struct ata_eh_info eh_info; /* EH context */ struct ata_eh_context eh_context; struct ata_device device[ATA_MAX_DEVICES]; unsigned long last_lpm_change; /* when last LPM change happened */ }; #define ATA_LINK_CLEAR_BEGIN offsetof(struct ata_link, active_tag) #define ATA_LINK_CLEAR_END offsetof(struct ata_link, device[0]) struct ata_port { struct Scsi_Host *scsi_host; /* our co-allocated scsi host */ struct ata_port_operations *ops; spinlock_t *lock; /* Flags owned by the EH context. Only EH should touch these once the port is active */ unsigned long flags; /* ATA_FLAG_xxx */ /* Flags that change dynamically, protected by ap->lock */ unsigned int pflags; /* ATA_PFLAG_xxx */ unsigned int print_id; /* user visible unique port ID */ unsigned int local_port_no; /* host local port num */ unsigned int port_no; /* 0 based port no. inside the host */ #ifdef CONFIG_ATA_SFF struct ata_ioports ioaddr; /* ATA cmd/ctl/dma register blocks */ u8 ctl; /* cache of ATA control register */ u8 last_ctl; /* Cache last written value */ struct ata_link* sff_pio_task_link; /* link currently used */ struct delayed_work sff_pio_task; #ifdef CONFIG_ATA_BMDMA struct ata_bmdma_prd *bmdma_prd; /* BMDMA SG list */ dma_addr_t bmdma_prd_dma; /* and its DMA mapping */ #endif /* CONFIG_ATA_BMDMA */ #endif /* CONFIG_ATA_SFF */ unsigned int pio_mask; unsigned int mwdma_mask; unsigned int udma_mask; unsigned int cbl; /* cable type; ATA_CBL_xxx */ struct ata_queued_cmd qcmd[ATA_MAX_QUEUE + 1]; unsigned long sas_tag_allocated; /* for sas tag allocation only */ u64 qc_active; int nr_active_links; /* #links with active qcs */ unsigned int sas_last_tag; /* track next tag hw expects */ struct ata_link link; /* host default link */ struct ata_link *slave_link; /* see ata_slave_link_init() */ int nr_pmp_links; /* nr of available PMP links */ struct ata_link *pmp_link; /* array of PMP links */ struct ata_link *excl_link; /* for PMP qc exclusion */ struct ata_port_stats stats; struct ata_host *host; struct device *dev; struct device tdev; struct mutex scsi_scan_mutex; struct delayed_work hotplug_task; struct work_struct scsi_rescan_task; unsigned int hsm_task_state; u32 msg_enable; struct list_head eh_done_q; wait_queue_head_t eh_wait_q; int eh_tries; struct completion park_req_pending; pm_message_t pm_mesg; enum ata_lpm_policy target_lpm_policy; struct timer_list fastdrain_timer; unsigned long fastdrain_cnt; async_cookie_t cookie; int em_message_type; void *private_data; #ifdef CONFIG_ATA_ACPI struct ata_acpi_gtm __acpi_init_gtm; /* use ata_acpi_init_gtm() */ #endif /* owned by EH */ u8 sector_buf[ATA_SECT_SIZE] ____cacheline_aligned; }; /* The following initializer overrides a method to NULL whether one of * its parent has the method defined or not. This is equivalent to * ERR_PTR(-ENOENT). Unfortunately, ERR_PTR doesn't render a constant * expression and thus can't be used as an initializer. */ #define ATA_OP_NULL (void *)(unsigned long)(-ENOENT) struct ata_port_operations { /* * Command execution */ int (*qc_defer)(struct ata_queued_cmd *qc); int (*check_atapi_dma)(struct ata_queued_cmd *qc); enum ata_completion_errors (*qc_prep)(struct ata_queued_cmd *qc); unsigned int (*qc_issue)(struct ata_queued_cmd *qc); bool (*qc_fill_rtf)(struct ata_queued_cmd *qc); /* * Configuration and exception handling */ int (*cable_detect)(struct ata_port *ap); unsigned long (*mode_filter)(struct ata_device *dev, unsigned long xfer_mask); void (*set_piomode)(struct ata_port *ap, struct ata_device *dev); void (*set_dmamode)(struct ata_port *ap, struct ata_device *dev); int (*set_mode)(struct ata_link *link, struct ata_device **r_failed_dev); unsigned int (*read_id)(struct ata_device *dev, struct ata_taskfile *tf, u16 *id); void (*dev_config)(struct ata_device *dev); void (*freeze)(struct ata_port *ap); void (*thaw)(struct ata_port *ap); ata_prereset_fn_t prereset; ata_reset_fn_t softreset; ata_reset_fn_t hardreset; ata_postreset_fn_t postreset; ata_prereset_fn_t pmp_prereset; ata_reset_fn_t pmp_softreset; ata_reset_fn_t pmp_hardreset; ata_postreset_fn_t pmp_postreset; void (*error_handler)(struct ata_port *ap); void (*lost_interrupt)(struct ata_port *ap); void (*post_internal_cmd)(struct ata_queued_cmd *qc); void (*sched_eh)(struct ata_port *ap); void (*end_eh)(struct ata_port *ap); /* * Optional features */ int (*scr_read)(struct ata_link *link, unsigned int sc_reg, u32 *val); int (*scr_write)(struct ata_link *link, unsigned int sc_reg, u32 val); void (*pmp_attach)(struct ata_port *ap); void (*pmp_detach)(struct ata_port *ap); int (*set_lpm)(struct ata_link *link, enum ata_lpm_policy policy, unsigned hints); /* * Start, stop, suspend and resume */ int (*port_suspend)(struct ata_port *ap, pm_message_t mesg); int (*port_resume)(struct ata_port *ap); int (*port_start)(struct ata_port *ap); void (*port_stop)(struct ata_port *ap); void (*host_stop)(struct ata_host *host); #ifdef CONFIG_ATA_SFF /* * SFF / taskfile oriented ops */ void (*sff_dev_select)(struct ata_port *ap, unsigned int device); void (*sff_set_devctl)(struct ata_port *ap, u8 ctl); u8 (*sff_check_status)(struct ata_port *ap); u8 (*sff_check_altstatus)(struct ata_port *ap); void (*sff_tf_load)(struct ata_port *ap, const struct ata_taskfile *tf); void (*sff_tf_read)(struct ata_port *ap, struct ata_taskfile *tf); void (*sff_exec_command)(struct ata_port *ap, const struct ata_taskfile *tf); unsigned int (*sff_data_xfer)(struct ata_queued_cmd *qc, unsigned char *buf, unsigned int buflen, int rw); void (*sff_irq_on)(struct ata_port *); bool (*sff_irq_check)(struct ata_port *); void (*sff_irq_clear)(struct ata_port *); void (*sff_drain_fifo)(struct ata_queued_cmd *qc); #ifdef CONFIG_ATA_BMDMA void (*bmdma_setup)(struct ata_queued_cmd *qc); void (*bmdma_start)(struct ata_queued_cmd *qc); void (*bmdma_stop)(struct ata_queued_cmd *qc); u8 (*bmdma_status)(struct ata_port *ap); #endif /* CONFIG_ATA_BMDMA */ #endif /* CONFIG_ATA_SFF */ ssize_t (*em_show)(struct ata_port *ap, char *buf); ssize_t (*em_store)(struct ata_port *ap, const char *message, size_t size); ssize_t (*sw_activity_show)(struct ata_device *dev, char *buf); ssize_t (*sw_activity_store)(struct ata_device *dev, enum sw_activity val); ssize_t (*transmit_led_message)(struct ata_port *ap, u32 state, ssize_t size); /* * Obsolete */ void (*phy_reset)(struct ata_port *ap); void (*eng_timeout)(struct ata_port *ap); /* * ->inherits must be the last field and all the preceding * fields must be pointers. */ const struct ata_port_operations *inherits; }; struct ata_port_info { unsigned long flags; unsigned long link_flags; unsigned long pio_mask; unsigned long mwdma_mask; unsigned long udma_mask; struct ata_port_operations *port_ops; void *private_data; }; struct ata_timing { unsigned short mode; /* ATA mode */ unsigned short setup; /* t1 */ unsigned short act8b; /* t2 for 8-bit I/O */ unsigned short rec8b; /* t2i for 8-bit I/O */ unsigned short cyc8b; /* t0 for 8-bit I/O */ unsigned short active; /* t2 or tD */ unsigned short recover; /* t2i or tK */ unsigned short dmack_hold; /* tj */ unsigned short cycle; /* t0 */ unsigned short udma; /* t2CYCTYP/2 */ }; /* * Core layer - drivers/ata/libata-core.c */ extern struct ata_port_operations ata_dummy_port_ops; extern const struct ata_port_info ata_dummy_port_info; static inline bool ata_is_atapi(u8 prot) { return prot & ATA_PROT_FLAG_ATAPI; } static inline bool ata_is_pio(u8 prot) { return prot & ATA_PROT_FLAG_PIO; } static inline bool ata_is_dma(u8 prot) { return prot & ATA_PROT_FLAG_DMA; } static inline bool ata_is_ncq(u8 prot) { return prot & ATA_PROT_FLAG_NCQ; } static inline bool ata_is_data(u8 prot) { return prot & (ATA_PROT_FLAG_PIO | ATA_PROT_FLAG_DMA); } static inline int is_multi_taskfile(struct ata_taskfile *tf) { return (tf->command == ATA_CMD_READ_MULTI) || (tf->command == ATA_CMD_WRITE_MULTI) || (tf->command == ATA_CMD_READ_MULTI_EXT) || (tf->command == ATA_CMD_WRITE_MULTI_EXT) || (tf->command == ATA_CMD_WRITE_MULTI_FUA_EXT); } static inline int ata_port_is_dummy(struct ata_port *ap) { return ap->ops == &ata_dummy_port_ops; } extern int ata_std_prereset(struct ata_link *link, unsigned long deadline); extern int ata_wait_after_reset(struct ata_link *link, unsigned long deadline, int (*check_ready)(struct ata_link *link)); extern int sata_std_hardreset(struct ata_link *link, unsigned int *class, unsigned long deadline); extern void ata_std_postreset(struct ata_link *link, unsigned int *classes); extern struct ata_host *ata_host_alloc(struct device *dev, int max_ports); extern struct ata_host *ata_host_alloc_pinfo(struct device *dev, const struct ata_port_info * const * ppi, int n_ports); extern void ata_host_get(struct ata_host *host); extern void ata_host_put(struct ata_host *host); extern int ata_host_start(struct ata_host *host); extern int ata_host_register(struct ata_host *host, struct scsi_host_template *sht); extern int ata_host_activate(struct ata_host *host, int irq, irq_handler_t irq_handler, unsigned long irq_flags, struct scsi_host_template *sht); extern void ata_host_detach(struct ata_host *host); extern void ata_host_init(struct ata_host *, struct device *, struct ata_port_operations *); extern int ata_scsi_detect(struct scsi_host_template *sht); extern int ata_scsi_ioctl(struct scsi_device *dev, unsigned int cmd, void __user *arg); #ifdef CONFIG_COMPAT #define ATA_SCSI_COMPAT_IOCTL .compat_ioctl = ata_scsi_ioctl, #else #define ATA_SCSI_COMPAT_IOCTL /* empty */ #endif extern int ata_scsi_queuecmd(struct Scsi_Host *h, struct scsi_cmnd *cmd); #if IS_REACHABLE(CONFIG_ATA) bool ata_scsi_dma_need_drain(struct request *rq); #else #define ata_scsi_dma_need_drain NULL #endif extern int ata_sas_scsi_ioctl(struct ata_port *ap, struct scsi_device *dev, unsigned int cmd, void __user *arg); extern bool ata_link_online(struct ata_link *link); extern bool ata_link_offline(struct ata_link *link); #ifdef CONFIG_PM extern int ata_host_suspend(struct ata_host *host, pm_message_t mesg); extern void ata_host_resume(struct ata_host *host); extern void ata_sas_port_suspend(struct ata_port *ap); extern void ata_sas_port_resume(struct ata_port *ap); #else static inline void ata_sas_port_suspend(struct ata_port *ap) { } static inline void ata_sas_port_resume(struct ata_port *ap) { } #endif extern int ata_ratelimit(void); extern void ata_msleep(struct ata_port *ap, unsigned int msecs); extern u32 ata_wait_register(struct ata_port *ap, void __iomem *reg, u32 mask, u32 val, unsigned long interval, unsigned long timeout); extern int atapi_cmd_type(u8 opcode); extern unsigned long ata_pack_xfermask(unsigned long pio_mask, unsigned long mwdma_mask, unsigned long udma_mask); extern void ata_unpack_xfermask(unsigned long xfer_mask, unsigned long *pio_mask, unsigned long *mwdma_mask, unsigned long *udma_mask); extern u8 ata_xfer_mask2mode(unsigned long xfer_mask); extern unsigned long ata_xfer_mode2mask(u8 xfer_mode); extern int ata_xfer_mode2shift(unsigned long xfer_mode); extern const char *ata_mode_string(unsigned long xfer_mask); extern unsigned long ata_id_xfermask(const u16 *id); extern int ata_std_qc_defer(struct ata_queued_cmd *qc); extern enum ata_completion_errors ata_noop_qc_prep(struct ata_queued_cmd *qc); extern void ata_sg_init(struct ata_queued_cmd *qc, struct scatterlist *sg, unsigned int n_elem); extern unsigned int ata_dev_classify(const struct ata_taskfile *tf); extern void ata_dev_disable(struct ata_device *adev); extern void ata_id_string(const u16 *id, unsigned char *s, unsigned int ofs, unsigned int len); extern void ata_id_c_string(const u16 *id, unsigned char *s, unsigned int ofs, unsigned int len); extern unsigned int ata_do_dev_read_id(struct ata_device *dev, struct ata_taskfile *tf, u16 *id); extern void ata_qc_complete(struct ata_queued_cmd *qc); extern u64 ata_qc_get_active(struct ata_port *ap); extern void ata_scsi_simulate(struct ata_device *dev, struct scsi_cmnd *cmd); extern int ata_std_bios_param(struct scsi_device *sdev, struct block_device *bdev, sector_t capacity, int geom[]); extern void ata_scsi_unlock_native_capacity(struct scsi_device *sdev); extern int ata_scsi_slave_config(struct scsi_device *sdev); extern void ata_scsi_slave_destroy(struct scsi_device *sdev); extern int ata_scsi_change_queue_depth(struct scsi_device *sdev, int queue_depth); extern int __ata_change_queue_depth(struct ata_port *ap, struct scsi_device *sdev, int queue_depth); extern struct ata_device *ata_dev_pair(struct ata_device *adev); extern int ata_do_set_mode(struct ata_link *link, struct ata_device **r_failed_dev); extern void ata_scsi_port_error_handler(struct Scsi_Host *host, struct ata_port *ap); extern void ata_scsi_cmd_error_handler(struct Scsi_Host *host, struct ata_port *ap, struct list_head *eh_q); /* * SATA specific code - drivers/ata/libata-sata.c */ #ifdef CONFIG_SATA_HOST extern const unsigned long sata_deb_timing_normal[]; extern const unsigned long sata_deb_timing_hotplug[]; extern const unsigned long sata_deb_timing_long[]; static inline const unsigned long * sata_ehc_deb_timing(struct ata_eh_context *ehc) { if (ehc->i.flags & ATA_EHI_HOTPLUGGED) return sata_deb_timing_hotplug; else return sata_deb_timing_normal; } extern int sata_scr_valid(struct ata_link *link); extern int sata_scr_read(struct ata_link *link, int reg, u32 *val); extern int sata_scr_write(struct ata_link *link, int reg, u32 val); extern int sata_scr_write_flush(struct ata_link *link, int reg, u32 val); extern int sata_set_spd(struct ata_link *link); extern int sata_link_hardreset(struct ata_link *link, const unsigned long *timing, unsigned long deadline, bool *online, int (*check_ready)(struct ata_link *)); extern int sata_link_resume(struct ata_link *link, const unsigned long *params, unsigned long deadline); extern void ata_eh_analyze_ncq_error(struct ata_link *link); #else static inline const unsigned long * sata_ehc_deb_timing(struct ata_eh_context *ehc) { return NULL; } static inline int sata_scr_valid(struct ata_link *link) { return 0; } static inline int sata_scr_read(struct ata_link *link, int reg, u32 *val) { return -EOPNOTSUPP; } static inline int sata_scr_write(struct ata_link *link, int reg, u32 val) { return -EOPNOTSUPP; } static inline int sata_scr_write_flush(struct ata_link *link, int reg, u32 val) { return -EOPNOTSUPP; } static inline int sata_set_spd(struct ata_link *link) { return -EOPNOTSUPP; } static inline int sata_link_hardreset(struct ata_link *link, const unsigned long *timing, unsigned long deadline, bool *online, int (*check_ready)(struct ata_link *)) { if (online) *online = false; return -EOPNOTSUPP; } static inline int sata_link_resume(struct ata_link *link, const unsigned long *params, unsigned long deadline) { return -EOPNOTSUPP; } static inline void ata_eh_analyze_ncq_error(struct ata_link *link) { } #endif extern int sata_link_debounce(struct ata_link *link, const unsigned long *params, unsigned long deadline); extern int sata_link_scr_lpm(struct ata_link *link, enum ata_lpm_policy policy, bool spm_wakeup); extern int ata_slave_link_init(struct ata_port *ap); extern void ata_sas_port_destroy(struct ata_port *); extern struct ata_port *ata_sas_port_alloc(struct ata_host *, struct ata_port_info *, struct Scsi_Host *); extern void ata_sas_async_probe(struct ata_port *ap); extern int ata_sas_sync_probe(struct ata_port *ap); extern int ata_sas_port_init(struct ata_port *); extern int ata_sas_port_start(struct ata_port *ap); extern int ata_sas_tport_add(struct device *parent, struct ata_port *ap); extern void ata_sas_tport_delete(struct ata_port *ap); extern void ata_sas_port_stop(struct ata_port *ap); extern int ata_sas_slave_configure(struct scsi_device *, struct ata_port *); extern int ata_sas_queuecmd(struct scsi_cmnd *cmd, struct ata_port *ap); extern void ata_tf_to_fis(const struct ata_taskfile *tf, u8 pmp, int is_cmd, u8 *fis); extern void ata_tf_from_fis(const u8 *fis, struct ata_taskfile *tf); extern int ata_qc_complete_multiple(struct ata_port *ap, u64 qc_active); extern bool sata_lpm_ignore_phy_events(struct ata_link *link); extern int sata_async_notification(struct ata_port *ap); extern int ata_cable_40wire(struct ata_port *ap); extern int ata_cable_80wire(struct ata_port *ap); extern int ata_cable_sata(struct ata_port *ap); extern int ata_cable_ignore(struct ata_port *ap); extern int ata_cable_unknown(struct ata_port *ap); /* Timing helpers */ extern unsigned int ata_pio_need_iordy(const struct ata_device *); extern u8 ata_timing_cycle2mode(unsigned int xfer_shift, int cycle); /* PCI */ #ifdef CONFIG_PCI struct pci_dev; struct pci_bits { unsigned int reg; /* PCI config register to read */ unsigned int width; /* 1 (8 bit), 2 (16 bit), 4 (32 bit) */ unsigned long mask; unsigned long val; }; extern int pci_test_config_bits(struct pci_dev *pdev, const struct pci_bits *bits); extern void ata_pci_shutdown_one(struct pci_dev *pdev); extern void ata_pci_remove_one(struct pci_dev *pdev); #ifdef CONFIG_PM extern void ata_pci_device_do_suspend(struct pci_dev *pdev, pm_message_t mesg); extern int __must_check ata_pci_device_do_resume(struct pci_dev *pdev); extern int ata_pci_device_suspend(struct pci_dev *pdev, pm_message_t mesg); extern int ata_pci_device_resume(struct pci_dev *pdev); #endif /* CONFIG_PM */ #endif /* CONFIG_PCI */ struct platform_device; extern int ata_platform_remove_one(struct platform_device *pdev); /* * ACPI - drivers/ata/libata-acpi.c */ #ifdef CONFIG_ATA_ACPI static inline const struct ata_acpi_gtm *ata_acpi_init_gtm(struct ata_port *ap) { if (ap->pflags & ATA_PFLAG_INIT_GTM_VALID) return &ap->__acpi_init_gtm; return NULL; } int ata_acpi_stm(struct ata_port *ap, const struct ata_acpi_gtm *stm); int ata_acpi_gtm(struct ata_port *ap, struct ata_acpi_gtm *stm); unsigned long ata_acpi_gtm_xfermask(struct ata_device *dev, const struct ata_acpi_gtm *gtm); int ata_acpi_cbl_80wire(struct ata_port *ap, const struct ata_acpi_gtm *gtm); #else static inline const struct ata_acpi_gtm *ata_acpi_init_gtm(struct ata_port *ap) { return NULL; } static inline int ata_acpi_stm(const struct ata_port *ap, struct ata_acpi_gtm *stm) { return -ENOSYS; } static inline int ata_acpi_gtm(const struct ata_port *ap, struct ata_acpi_gtm *stm) { return -ENOSYS; } static inline unsigned int ata_acpi_gtm_xfermask(struct ata_device *dev, const struct ata_acpi_gtm *gtm) { return 0; } static inline int ata_acpi_cbl_80wire(struct ata_port *ap, const struct ata_acpi_gtm *gtm) { return 0; } #endif /* * EH - drivers/ata/libata-eh.c */ extern void ata_port_schedule_eh(struct ata_port *ap); extern void ata_port_wait_eh(struct ata_port *ap); extern int ata_link_abort(struct ata_link *link); extern int ata_port_abort(struct ata_port *ap); extern int ata_port_freeze(struct ata_port *ap); extern void ata_eh_freeze_port(struct ata_port *ap); extern void ata_eh_thaw_port(struct ata_port *ap); extern void ata_eh_qc_complete(struct ata_queued_cmd *qc); extern void ata_eh_qc_retry(struct ata_queued_cmd *qc); extern void ata_do_eh(struct ata_port *ap, ata_prereset_fn_t prereset, ata_reset_fn_t softreset, ata_reset_fn_t hardreset, ata_postreset_fn_t postreset); extern void ata_std_error_handler(struct ata_port *ap); extern void ata_std_sched_eh(struct ata_port *ap); extern void ata_std_end_eh(struct ata_port *ap); extern int ata_link_nr_enabled(struct ata_link *link); /* * Base operations to inherit from and initializers for sht * * Operations * * base : Common to all libata drivers. * sata : SATA controllers w/ native interface. * pmp : SATA controllers w/ PMP support. * sff : SFF ATA controllers w/o BMDMA support. * bmdma : SFF ATA controllers w/ BMDMA support. * * sht initializers * * BASE : Common to all libata drivers. The user must set * sg_tablesize and dma_boundary. * PIO : SFF ATA controllers w/ only PIO support. * BMDMA : SFF ATA controllers w/ BMDMA support. sg_tablesize and * dma_boundary are set to BMDMA limits. * NCQ : SATA controllers supporting NCQ. The user must set * sg_tablesize, dma_boundary and can_queue. */ extern const struct ata_port_operations ata_base_port_ops; extern const struct ata_port_operations sata_port_ops; extern struct device_attribute *ata_common_sdev_attrs[]; /* * All sht initializers (BASE, PIO, BMDMA, NCQ) must be instantiated * by the edge drivers. Because the 'module' field of sht must be the * edge driver's module reference, otherwise the driver can be unloaded * even if the scsi_device is being accessed. */ #define __ATA_BASE_SHT(drv_name) \ .module = THIS_MODULE, \ .name = drv_name, \ .ioctl = ata_scsi_ioctl, \ ATA_SCSI_COMPAT_IOCTL \ .queuecommand = ata_scsi_queuecmd, \ .dma_need_drain = ata_scsi_dma_need_drain, \ .can_queue = ATA_DEF_QUEUE, \ .tag_alloc_policy = BLK_TAG_ALLOC_RR, \ .this_id = ATA_SHT_THIS_ID, \ .emulated = ATA_SHT_EMULATED, \ .proc_name = drv_name, \ .slave_configure = ata_scsi_slave_config, \ .slave_destroy = ata_scsi_slave_destroy, \ .bios_param = ata_std_bios_param, \ .unlock_native_capacity = ata_scsi_unlock_native_capacity #define ATA_BASE_SHT(drv_name) \ __ATA_BASE_SHT(drv_name), \ .sdev_attrs = ata_common_sdev_attrs #ifdef CONFIG_SATA_HOST extern struct device_attribute *ata_ncq_sdev_attrs[]; #define ATA_NCQ_SHT(drv_name) \ __ATA_BASE_SHT(drv_name), \ .sdev_attrs = ata_ncq_sdev_attrs, \ .change_queue_depth = ata_scsi_change_queue_depth #endif /* * PMP helpers */ #ifdef CONFIG_SATA_PMP static inline bool sata_pmp_supported(struct ata_port *ap) { return ap->flags & ATA_FLAG_PMP; } static inline bool sata_pmp_attached(struct ata_port *ap) { return ap->nr_pmp_links != 0; } static inline bool ata_is_host_link(const struct ata_link *link) { return link == &link->ap->link || link == link->ap->slave_link; } #else /* CONFIG_SATA_PMP */ static inline bool sata_pmp_supported(struct ata_port *ap) { return false; } static inline bool sata_pmp_attached(struct ata_port *ap) { return false; } static inline bool ata_is_host_link(const struct ata_link *link) { return 1; } #endif /* CONFIG_SATA_PMP */ static inline int sata_srst_pmp(struct ata_link *link) { if (sata_pmp_supported(link->ap) && ata_is_host_link(link)) return SATA_PMP_CTRL_PORT; return link->pmp; } /* * printk helpers */ __printf(3, 4) void ata_port_printk(const struct ata_port *ap, const char *level, const char *fmt, ...); __printf(3, 4) void ata_link_printk(const struct ata_link *link, const char *level, const char *fmt, ...); __printf(3, 4) void ata_dev_printk(const struct ata_device *dev, const char *level, const char *fmt, ...); #define ata_port_err(ap, fmt, ...) \ ata_port_printk(ap, KERN_ERR, fmt, ##__VA_ARGS__) #define ata_port_warn(ap, fmt, ...) \ ata_port_printk(ap, KERN_WARNING, fmt, ##__VA_ARGS__) #define ata_port_notice(ap, fmt, ...) \ ata_port_printk(ap, KERN_NOTICE, fmt, ##__VA_ARGS__) #define ata_port_info(ap, fmt, ...) \ ata_port_printk(ap, KERN_INFO, fmt, ##__VA_ARGS__) #define ata_port_dbg(ap, fmt, ...) \ ata_port_printk(ap, KERN_DEBUG, fmt, ##__VA_ARGS__) #define ata_link_err(link, fmt, ...) \ ata_link_printk(link, KERN_ERR, fmt, ##__VA_ARGS__) #define ata_link_warn(link, fmt, ...) \ ata_link_printk(link, KERN_WARNING, fmt, ##__VA_ARGS__) #define ata_link_notice(link, fmt, ...) \ ata_link_printk(link, KERN_NOTICE, fmt, ##__VA_ARGS__) #define ata_link_info(link, fmt, ...) \ ata_link_printk(link, KERN_INFO, fmt, ##__VA_ARGS__) #define ata_link_dbg(link, fmt, ...) \ ata_link_printk(link, KERN_DEBUG, fmt, ##__VA_ARGS__) #define ata_dev_err(dev, fmt, ...) \ ata_dev_printk(dev, KERN_ERR, fmt, ##__VA_ARGS__) #define ata_dev_warn(dev, fmt, ...) \ ata_dev_printk(dev, KERN_WARNING, fmt, ##__VA_ARGS__) #define ata_dev_notice(dev, fmt, ...) \ ata_dev_printk(dev, KERN_NOTICE, fmt, ##__VA_ARGS__) #define ata_dev_info(dev, fmt, ...) \ ata_dev_printk(dev, KERN_INFO, fmt, ##__VA_ARGS__) #define ata_dev_dbg(dev, fmt, ...) \ ata_dev_printk(dev, KERN_DEBUG, fmt, ##__VA_ARGS__) void ata_print_version(const struct device *dev, const char *version); /* * ata_eh_info helpers */ extern __printf(2, 3) void __ata_ehi_push_desc(struct ata_eh_info *ehi, const char *fmt, ...); extern __printf(2, 3) void ata_ehi_push_desc(struct ata_eh_info *ehi, const char *fmt, ...); extern void ata_ehi_clear_desc(struct ata_eh_info *ehi); static inline void ata_ehi_hotplugged(struct ata_eh_info *ehi) { ehi->probe_mask |= (1 << ATA_MAX_DEVICES) - 1; ehi->flags |= ATA_EHI_HOTPLUGGED; ehi->action |= ATA_EH_RESET | ATA_EH_ENABLE_LINK; ehi->err_mask |= AC_ERR_ATA_BUS; } /* * port description helpers */ extern __printf(2, 3) void ata_port_desc(struct ata_port *ap, const char *fmt, ...); #ifdef CONFIG_PCI extern void ata_port_pbar_desc(struct ata_port *ap, int bar, ssize_t offset, const char *name); #endif static inline bool ata_tag_internal(unsigned int tag) { return tag == ATA_TAG_INTERNAL; } static inline bool ata_tag_valid(unsigned int tag) { return tag < ATA_MAX_QUEUE || ata_tag_internal(tag); } #define __ata_qc_for_each(ap, qc, tag, max_tag, fn) \ for ((tag) = 0; (tag) < (max_tag) && \ ({ qc = fn((ap), (tag)); 1; }); (tag)++) \ /* * Internal use only, iterate commands ignoring error handling and * status of 'qc'. */ #define ata_qc_for_each_raw(ap, qc, tag) \ __ata_qc_for_each(ap, qc, tag, ATA_MAX_QUEUE, __ata_qc_from_tag) /* * Iterate all potential commands that can be queued */ #define ata_qc_for_each(ap, qc, tag) \ __ata_qc_for_each(ap, qc, tag, ATA_MAX_QUEUE, ata_qc_from_tag) /* * Like ata_qc_for_each, but with the internal tag included */ #define ata_qc_for_each_with_internal(ap, qc, tag) \ __ata_qc_for_each(ap, qc, tag, ATA_MAX_QUEUE + 1, ata_qc_from_tag) /* * device helpers */ static inline unsigned int ata_class_enabled(unsigned int class) { return class == ATA_DEV_ATA || class == ATA_DEV_ATAPI || class == ATA_DEV_PMP || class == ATA_DEV_SEMB || class == ATA_DEV_ZAC; } static inline unsigned int ata_class_disabled(unsigned int class) { return class == ATA_DEV_ATA_UNSUP || class == ATA_DEV_ATAPI_UNSUP || class == ATA_DEV_PMP_UNSUP || class == ATA_DEV_SEMB_UNSUP || class == ATA_DEV_ZAC_UNSUP; } static inline unsigned int ata_class_absent(unsigned int class) { return !ata_class_enabled(class) && !ata_class_disabled(class); } static inline unsigned int ata_dev_enabled(const struct ata_device *dev) { return ata_class_enabled(dev->class); } static inline unsigned int ata_dev_disabled(const struct ata_device *dev) { return ata_class_disabled(dev->class); } static inline unsigned int ata_dev_absent(const struct ata_device *dev) { return ata_class_absent(dev->class); } /* * link helpers */ static inline int ata_link_max_devices(const struct ata_link *link) { if (ata_is_host_link(link) && link->ap->flags & ATA_FLAG_SLAVE_POSS) return 2; return 1; } static inline int ata_link_active(struct ata_link *link) { return ata_tag_valid(link->active_tag) || link->sactive; } /* * Iterators * * ATA_LITER_* constants are used to select link iteration mode and * ATA_DITER_* device iteration mode. * * For a custom iteration directly using ata_{link|dev}_next(), if * @link or @dev, respectively, is NULL, the first element is * returned. @dev and @link can be any valid device or link and the * next element according to the iteration mode will be returned. * After the last element, NULL is returned. */ enum ata_link_iter_mode { ATA_LITER_EDGE, /* if present, PMP links only; otherwise, * host link. no slave link */ ATA_LITER_HOST_FIRST, /* host link followed by PMP or slave links */ ATA_LITER_PMP_FIRST, /* PMP links followed by host link, * slave link still comes after host link */ }; enum ata_dev_iter_mode { ATA_DITER_ENABLED, ATA_DITER_ENABLED_REVERSE, ATA_DITER_ALL, ATA_DITER_ALL_REVERSE, }; extern struct ata_link *ata_link_next(struct ata_link *link, struct ata_port *ap, enum ata_link_iter_mode mode); extern struct ata_device *ata_dev_next(struct ata_device *dev, struct ata_link *link, enum ata_dev_iter_mode mode); /* * Shortcut notation for iterations * * ata_for_each_link() iterates over each link of @ap according to * @mode. @link points to the current link in the loop. @link is * NULL after loop termination. ata_for_each_dev() works the same way * except that it iterates over each device of @link. * * Note that the mode prefixes ATA_{L|D}ITER_ shouldn't need to be * specified when using the following shorthand notations. Only the * mode itself (EDGE, HOST_FIRST, ENABLED, etc...) should be * specified. This not only increases brevity but also makes it * impossible to use ATA_LITER_* for device iteration or vice-versa. */ #define ata_for_each_link(link, ap, mode) \ for ((link) = ata_link_next(NULL, (ap), ATA_LITER_##mode); (link); \ (link) = ata_link_next((link), (ap), ATA_LITER_##mode)) #define ata_for_each_dev(dev, link, mode) \ for ((dev) = ata_dev_next(NULL, (link), ATA_DITER_##mode); (dev); \ (dev) = ata_dev_next((dev), (link), ATA_DITER_##mode)) /** * ata_ncq_enabled - Test whether NCQ is enabled * @dev: ATA device to test for * * LOCKING: * spin_lock_irqsave(host lock) * * RETURNS: * 1 if NCQ is enabled for @dev, 0 otherwise. */ static inline int ata_ncq_enabled(struct ata_device *dev) { if (!IS_ENABLED(CONFIG_SATA_HOST)) return 0; return (dev->flags & (ATA_DFLAG_PIO | ATA_DFLAG_NCQ_OFF | ATA_DFLAG_NCQ)) == ATA_DFLAG_NCQ; } static inline bool ata_fpdma_dsm_supported(struct ata_device *dev) { return (dev->flags & ATA_DFLAG_NCQ_SEND_RECV) && (dev->ncq_send_recv_cmds[ATA_LOG_NCQ_SEND_RECV_DSM_OFFSET] & ATA_LOG_NCQ_SEND_RECV_DSM_TRIM); } static inline bool ata_fpdma_read_log_supported(struct ata_device *dev) { return (dev->flags & ATA_DFLAG_NCQ_SEND_RECV) && (dev->ncq_send_recv_cmds[ATA_LOG_NCQ_SEND_RECV_RD_LOG_OFFSET] & ATA_LOG_NCQ_SEND_RECV_RD_LOG_SUPPORTED); } static inline bool ata_fpdma_zac_mgmt_in_supported(struct ata_device *dev) { return (dev->flags & ATA_DFLAG_NCQ_SEND_RECV) && (dev->ncq_send_recv_cmds[ATA_LOG_NCQ_SEND_RECV_ZAC_MGMT_OFFSET] & ATA_LOG_NCQ_SEND_RECV_ZAC_MGMT_IN_SUPPORTED); } static inline bool ata_fpdma_zac_mgmt_out_supported(struct ata_device *dev) { return (dev->ncq_non_data_cmds[ATA_LOG_NCQ_NON_DATA_ZAC_MGMT_OFFSET] & ATA_LOG_NCQ_NON_DATA_ZAC_MGMT_OUT); } static inline void ata_qc_set_polling(struct ata_queued_cmd *qc) { qc->tf.ctl |= ATA_NIEN; } static inline struct ata_queued_cmd *__ata_qc_from_tag(struct ata_port *ap, unsigned int tag) { if (ata_tag_valid(tag)) return &ap->qcmd[tag]; return NULL; } static inline struct ata_queued_cmd *ata_qc_from_tag(struct ata_port *ap, unsigned int tag) { struct ata_queued_cmd *qc = __ata_qc_from_tag(ap, tag); if (unlikely(!qc) || !ap->ops->error_handler) return qc; if ((qc->flags & (ATA_QCFLAG_ACTIVE | ATA_QCFLAG_FAILED)) == ATA_QCFLAG_ACTIVE) return qc; return NULL; } static inline unsigned int ata_qc_raw_nbytes(struct ata_queued_cmd *qc) { return qc->nbytes - min(qc->extrabytes, qc->nbytes); } static inline void ata_tf_init(struct ata_device *dev, struct ata_taskfile *tf) { memset(tf, 0, sizeof(*tf)); #ifdef CONFIG_ATA_SFF tf->ctl = dev->link->ap->ctl; #else tf->ctl = ATA_DEVCTL_OBS; #endif if (dev->devno == 0) tf->device = ATA_DEVICE_OBS; else tf->device = ATA_DEVICE_OBS | ATA_DEV1; } static inline void ata_qc_reinit(struct ata_queued_cmd *qc) { qc->dma_dir = DMA_NONE; qc->sg = NULL; qc->flags = 0; qc->cursg = NULL; qc->cursg_ofs = 0; qc->nbytes = qc->extrabytes = qc->curbytes = 0; qc->n_elem = 0; qc->err_mask = 0; qc->sect_size = ATA_SECT_SIZE; ata_tf_init(qc->dev, &qc->tf); /* init result_tf such that it indicates normal completion */ qc->result_tf.command = ATA_DRDY; qc->result_tf.feature = 0; } static inline int ata_try_flush_cache(const struct ata_device *dev) { return ata_id_wcache_enabled(dev->id) || ata_id_has_flush(dev->id) || ata_id_has_flush_ext(dev->id); } static inline unsigned int ac_err_mask(u8 status) { if (status & (ATA_BUSY | ATA_DRQ)) return AC_ERR_HSM; if (status & (ATA_ERR | ATA_DF)) return AC_ERR_DEV; return 0; } static inline unsigned int __ac_err_mask(u8 status) { unsigned int mask = ac_err_mask(status); if (mask == 0) return AC_ERR_OTHER; return mask; } static inline struct ata_port *ata_shost_to_port(struct Scsi_Host *host) { return *(struct ata_port **)&host->hostdata[0]; } static inline int ata_check_ready(u8 status) { if (!(status & ATA_BUSY)) return 1; /* 0xff indicates either no device or device not ready */ if (status == 0xff) return -ENODEV; return 0; } static inline unsigned long ata_deadline(unsigned long from_jiffies, unsigned long timeout_msecs) { return from_jiffies + msecs_to_jiffies(timeout_msecs); } /* Don't open code these in drivers as there are traps. Firstly the range may change in future hardware and specs, secondly 0xFF means 'no DMA' but is > UDMA_0. Dyma ddreigiau */ static inline int ata_using_mwdma(struct ata_device *adev) { if (adev->dma_mode >= XFER_MW_DMA_0 && adev->dma_mode <= XFER_MW_DMA_4) return 1; return 0; } static inline int ata_using_udma(struct ata_device *adev) { if (adev->dma_mode >= XFER_UDMA_0 && adev->dma_mode <= XFER_UDMA_7) return 1; return 0; } static inline int ata_dma_enabled(struct ata_device *adev) { return (adev->dma_mode == 0xFF ? 0 : 1); } /************************************************************************** * PATA timings - drivers/ata/libata-pata-timings.c */ extern const struct ata_timing *ata_timing_find_mode(u8 xfer_mode); extern int ata_timing_compute(struct ata_device *, unsigned short, struct ata_timing *, int, int); extern void ata_timing_merge(const struct ata_timing *, const struct ata_timing *, struct ata_timing *, unsigned int); /************************************************************************** * PMP - drivers/ata/libata-pmp.c */ #ifdef CONFIG_SATA_PMP extern const struct ata_port_operations sata_pmp_port_ops; extern int sata_pmp_qc_defer_cmd_switch(struct ata_queued_cmd *qc); extern void sata_pmp_error_handler(struct ata_port *ap); #else /* CONFIG_SATA_PMP */ #define sata_pmp_port_ops sata_port_ops #define sata_pmp_qc_defer_cmd_switch ata_std_qc_defer #define sata_pmp_error_handler ata_std_error_handler #endif /* CONFIG_SATA_PMP */ /************************************************************************** * SFF - drivers/ata/libata-sff.c */ #ifdef CONFIG_ATA_SFF extern const struct ata_port_operations ata_sff_port_ops; extern const struct ata_port_operations ata_bmdma32_port_ops; /* PIO only, sg_tablesize and dma_boundary limits can be removed */ #define ATA_PIO_SHT(drv_name) \ ATA_BASE_SHT(drv_name), \ .sg_tablesize = LIBATA_MAX_PRD, \ .dma_boundary = ATA_DMA_BOUNDARY extern void ata_sff_dev_select(struct ata_port *ap, unsigned int device); extern u8 ata_sff_check_status(struct ata_port *ap); extern void ata_sff_pause(struct ata_port *ap); extern void ata_sff_dma_pause(struct ata_port *ap); extern int ata_sff_busy_sleep(struct ata_port *ap, unsigned long timeout_pat, unsigned long timeout); extern int ata_sff_wait_ready(struct ata_link *link, unsigned long deadline); extern void ata_sff_tf_load(struct ata_port *ap, const struct ata_taskfile *tf); extern void ata_sff_tf_read(struct ata_port *ap, struct ata_taskfile *tf); extern void ata_sff_exec_command(struct ata_port *ap, const struct ata_taskfile *tf); extern unsigned int ata_sff_data_xfer(struct ata_queued_cmd *qc, unsigned char *buf, unsigned int buflen, int rw); extern unsigned int ata_sff_data_xfer32(struct ata_queued_cmd *qc, unsigned char *buf, unsigned int buflen, int rw); extern void ata_sff_irq_on(struct ata_port *ap); extern void ata_sff_irq_clear(struct ata_port *ap); extern int ata_sff_hsm_move(struct ata_port *ap, struct ata_queued_cmd *qc, u8 status, int in_wq); extern void ata_sff_queue_work(struct work_struct *work); extern void ata_sff_queue_delayed_work(struct delayed_work *dwork, unsigned long delay); extern void ata_sff_queue_pio_task(struct ata_link *link, unsigned long delay); extern unsigned int ata_sff_qc_issue(struct ata_queued_cmd *qc); extern bool ata_sff_qc_fill_rtf(struct ata_queued_cmd *qc); extern unsigned int ata_sff_port_intr(struct ata_port *ap, struct ata_queued_cmd *qc); extern irqreturn_t ata_sff_interrupt(int irq, void *dev_instance); extern void ata_sff_lost_interrupt(struct ata_port *ap); extern void ata_sff_freeze(struct ata_port *ap); extern void ata_sff_thaw(struct ata_port *ap); extern int ata_sff_prereset(struct ata_link *link, unsigned long deadline); extern unsigned int ata_sff_dev_classify(struct ata_device *dev, int present, u8 *r_err); extern int ata_sff_wait_after_reset(struct ata_link *link, unsigned int devmask, unsigned long deadline); extern int ata_sff_softreset(struct ata_link *link, unsigned int *classes, unsigned long deadline); extern int sata_sff_hardreset(struct ata_link *link, unsigned int *class, unsigned long deadline); extern void ata_sff_postreset(struct ata_link *link, unsigned int *classes); extern void ata_sff_drain_fifo(struct ata_queued_cmd *qc); extern void ata_sff_error_handler(struct ata_port *ap); extern void ata_sff_std_ports(struct ata_ioports *ioaddr); #ifdef CONFIG_PCI extern int ata_pci_sff_init_host(struct ata_host *host); extern int ata_pci_sff_prepare_host(struct pci_dev *pdev, const struct ata_port_info * const * ppi, struct ata_host **r_host); extern int ata_pci_sff_activate_host(struct ata_host *host, irq_handler_t irq_handler, struct scsi_host_template *sht); extern int ata_pci_sff_init_one(struct pci_dev *pdev, const struct ata_port_info * const * ppi, struct scsi_host_template *sht, void *host_priv, int hflags); #endif /* CONFIG_PCI */ #ifdef CONFIG_ATA_BMDMA extern const struct ata_port_operations ata_bmdma_port_ops; #define ATA_BMDMA_SHT(drv_name) \ ATA_BASE_SHT(drv_name), \ .sg_tablesize = LIBATA_MAX_PRD, \ .dma_boundary = ATA_DMA_BOUNDARY extern enum ata_completion_errors ata_bmdma_qc_prep(struct ata_queued_cmd *qc); extern unsigned int ata_bmdma_qc_issue(struct ata_queued_cmd *qc); extern enum ata_completion_errors ata_bmdma_dumb_qc_prep(struct ata_queued_cmd *qc); extern unsigned int ata_bmdma_port_intr(struct ata_port *ap, struct ata_queued_cmd *qc); extern irqreturn_t ata_bmdma_interrupt(int irq, void *dev_instance); extern void ata_bmdma_error_handler(struct ata_port *ap); extern void ata_bmdma_post_internal_cmd(struct ata_queued_cmd *qc); extern void ata_bmdma_irq_clear(struct ata_port *ap); extern void ata_bmdma_setup(struct ata_queued_cmd *qc); extern void ata_bmdma_start(struct ata_queued_cmd *qc); extern void ata_bmdma_stop(struct ata_queued_cmd *qc); extern u8 ata_bmdma_status(struct ata_port *ap); extern int ata_bmdma_port_start(struct ata_port *ap); extern int ata_bmdma_port_start32(struct ata_port *ap); #ifdef CONFIG_PCI extern int ata_pci_bmdma_clear_simplex(struct pci_dev *pdev); extern void ata_pci_bmdma_init(struct ata_host *host); extern int ata_pci_bmdma_prepare_host(struct pci_dev *pdev, const struct ata_port_info * const * ppi, struct ata_host **r_host); extern int ata_pci_bmdma_init_one(struct pci_dev *pdev, const struct ata_port_info * const * ppi, struct scsi_host_template *sht, void *host_priv, int hflags); #endif /* CONFIG_PCI */ #endif /* CONFIG_ATA_BMDMA */ /** * ata_sff_busy_wait - Wait for a port status register * @ap: Port to wait for. * @bits: bits that must be clear * @max: number of 10uS waits to perform * * Waits up to max*10 microseconds for the selected bits in the port's * status register to be cleared. * Returns final value of status register. * * LOCKING: * Inherited from caller. */ static inline u8 ata_sff_busy_wait(struct ata_port *ap, unsigned int bits, unsigned int max) { u8 status; do { udelay(10); status = ap->ops->sff_check_status(ap); max--; } while (status != 0xff && (status & bits) && (max > 0)); return status; } /** * ata_wait_idle - Wait for a port to be idle. * @ap: Port to wait for. * * Waits up to 10ms for port's BUSY and DRQ signals to clear. * Returns final value of status register. * * LOCKING: * Inherited from caller. */ static inline u8 ata_wait_idle(struct ata_port *ap) { u8 status = ata_sff_busy_wait(ap, ATA_BUSY | ATA_DRQ, 1000); #ifdef ATA_DEBUG if (status != 0xff && (status & (ATA_BUSY | ATA_DRQ))) ata_port_printk(ap, KERN_DEBUG, "abnormal Status 0x%X\n", status); #endif return status; } #endif /* CONFIG_ATA_SFF */ #endif /* __LINUX_LIBATA_H__ */
1 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 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 /* SPDX-License-Identifier: GPL-2.0 */ /* * Variant of atomic_t specialized for reference counts. * * The interface matches the atomic_t interface (to aid in porting) but only * provides the few functions one should use for reference counting. * * Saturation semantics * ==================== * * refcount_t differs from atomic_t in that the counter saturates at * REFCOUNT_SATURATED and will not move once there. This avoids wrapping the * counter and causing 'spurious' use-after-free issues. In order to avoid the * cost associated with introducing cmpxchg() loops into all of the saturating * operations, we temporarily allow the counter to take on an unchecked value * and then explicitly set it to REFCOUNT_SATURATED on detecting that underflow * or overflow has occurred. Although this is racy when multiple threads * access the refcount concurrently, by placing REFCOUNT_SATURATED roughly * equidistant from 0 and INT_MAX we minimise the scope for error: * * INT_MAX REFCOUNT_SATURATED UINT_MAX * 0 (0x7fff_ffff) (0xc000_0000) (0xffff_ffff) * +--------------------------------+----------------+----------------+ * <---------- bad value! ----------> * * (in a signed view of the world, the "bad value" range corresponds to * a negative counter value). * * As an example, consider a refcount_inc() operation that causes the counter * to overflow: * * int old = atomic_fetch_add_relaxed(r); * // old is INT_MAX, refcount now INT_MIN (0x8000_0000) * if (old < 0) * atomic_set(r, REFCOUNT_SATURATED); * * If another thread also performs a refcount_inc() operation between the two * atomic operations, then the count will continue to edge closer to 0. If it * reaches a value of 1 before /any/ of the threads reset it to the saturated * value, then a concurrent refcount_dec_and_test() may erroneously free the * underlying object. * Linux limits the maximum number of tasks to PID_MAX_LIMIT, which is currently * 0x400000 (and can't easily be raised in the future beyond FUTEX_TID_MASK). * With the current PID limit, if no batched refcounting operations are used and * the attacker can't repeatedly trigger kernel oopses in the middle of refcount * operations, this makes it impossible for a saturated refcount to leave the * saturation range, even if it is possible for multiple uses of the same * refcount to nest in the context of a single task: * * (UINT_MAX+1-REFCOUNT_SATURATED) / PID_MAX_LIMIT = * 0x40000000 / 0x400000 = 0x100 = 256 * * If hundreds of references are added/removed with a single refcounting * operation, it may potentially be possible to leave the saturation range; but * given the precise timing details involved with the round-robin scheduling of * each thread manipulating the refcount and the need to hit the race multiple * times in succession, there doesn't appear to be a practical avenue of attack * even if using refcount_add() operations with larger increments. * * Memory ordering * =============== * * Memory ordering rules are slightly relaxed wrt regular atomic_t functions * and provide only what is strictly required for refcounts. * * The increments are fully relaxed; these will not provide ordering. The * rationale is that whatever is used to obtain the object we're increasing the * reference count on will provide the ordering. For locked data structures, * its the lock acquire, for RCU/lockless data structures its the dependent * load. * * Do note that inc_not_zero() provides a control dependency which will order * future stores against the inc, this ensures we'll never modify the object * if we did not in fact acquire a reference. * * The decrements will provide release order, such that all the prior loads and * stores will be issued before, it also provides a control dependency, which * will order us against the subsequent free(). * * The control dependency is against the load of the cmpxchg (ll/sc) that * succeeded. This means the stores aren't fully ordered, but this is fine * because the 1->0 transition indicates no concurrency. * * Note that the allocator is responsible for ordering things between free() * and alloc(). * * The decrements dec_and_test() and sub_and_test() also provide acquire * ordering on success. * */ #ifndef _LINUX_REFCOUNT_H #define _LINUX_REFCOUNT_H #include <linux/atomic.h> #include <linux/bug.h> #include <linux/compiler.h> #include <linux/limits.h> #include <linux/spinlock_types.h> struct mutex; /** * struct refcount_t - variant of atomic_t specialized for reference counts * @refs: atomic_t counter field * * The counter saturates at REFCOUNT_SATURATED and will not move once * there. This avoids wrapping the counter and causing 'spurious' * use-after-free bugs. */ typedef struct refcount_struct { atomic_t refs; } refcount_t; #define REFCOUNT_INIT(n) { .refs = ATOMIC_INIT(n), } #define REFCOUNT_MAX INT_MAX #define REFCOUNT_SATURATED (INT_MIN / 2) enum refcount_saturation_type { REFCOUNT_ADD_NOT_ZERO_OVF, REFCOUNT_ADD_OVF, REFCOUNT_ADD_UAF, REFCOUNT_SUB_UAF, REFCOUNT_DEC_LEAK, }; void refcount_warn_saturate(refcount_t *r, enum refcount_saturation_type t); /** * refcount_set - set a refcount's value * @r: the refcount * @n: value to which the refcount will be set */ static inline void refcount_set(refcount_t *r, int n) { atomic_set(&r->refs, n); } /** * refcount_read - get a refcount's value * @r: the refcount * * Return: the refcount's value */ static inline unsigned int refcount_read(const refcount_t *r) { return atomic_read(&r->refs); } static inline __must_check bool __refcount_add_not_zero(int i, refcount_t *r, int *oldp) { int old = refcount_read(r); do { if (!old) break; } while (!atomic_try_cmpxchg_relaxed(&r->refs, &old, old + i)); if (oldp) *oldp = old; if (unlikely(old < 0 || old + i < 0)) refcount_warn_saturate(r, REFCOUNT_ADD_NOT_ZERO_OVF); return old; } /** * refcount_add_not_zero - add a value to a refcount unless it is 0 * @i: the value to add to the refcount * @r: the refcount * * Will saturate at REFCOUNT_SATURATED and WARN. * * Provides no memory ordering, it is assumed the caller has guaranteed the * object memory to be stable (RCU, etc.). It does provide a control dependency * and thereby orders future stores. See the comment on top. * * Use of this function is not recommended for the normal reference counting * use case in which references are taken and released one at a time. In these * cases, refcount_inc(), or one of its variants, should instead be used to * increment a reference count. * * Return: false if the passed refcount is 0, true otherwise */ static inline __must_check bool refcount_add_not_zero(int i, refcount_t *r) { return __refcount_add_not_zero(i, r, NULL); } static inline void __refcount_add(int i, refcount_t *r, int *oldp) { int old = atomic_fetch_add_relaxed(i, &r->refs); if (oldp) *oldp = old; if (unlikely(!old)) refcount_warn_saturate(r, REFCOUNT_ADD_UAF); else if (unlikely(old < 0 || old + i < 0)) refcount_warn_saturate(r, REFCOUNT_ADD_OVF); } /** * refcount_add - add a value to a refcount * @i: the value to add to the refcount * @r: the refcount * * Similar to atomic_add(), but will saturate at REFCOUNT_SATURATED and WARN. * * Provides no memory ordering, it is assumed the caller has guaranteed the * object memory to be stable (RCU, etc.). It does provide a control dependency * and thereby orders future stores. See the comment on top. * * Use of this function is not recommended for the normal reference counting * use case in which references are taken and released one at a time. In these * cases, refcount_inc(), or one of its variants, should instead be used to * increment a reference count. */ static inline void refcount_add(int i, refcount_t *r) { __refcount_add(i, r, NULL); } static inline __must_check bool __refcount_inc_not_zero(refcount_t *r, int *oldp) { return __refcount_add_not_zero(1, r, oldp); } /** * refcount_inc_not_zero - increment a refcount unless it is 0 * @r: the refcount to increment * * Similar to atomic_inc_not_zero(), but will saturate at REFCOUNT_SATURATED * and WARN. * * Provides no memory ordering, it is assumed the caller has guaranteed the * object memory to be stable (RCU, etc.). It does provide a control dependency * and thereby orders future stores. See the comment on top. * * Return: true if the increment was successful, false otherwise */ static inline __must_check bool refcount_inc_not_zero(refcount_t *r) { return __refcount_inc_not_zero(r, NULL); } static inline void __refcount_inc(refcount_t *r, int *oldp) { __refcount_add(1, r, oldp); } /** * refcount_inc - increment a refcount * @r: the refcount to increment * * Similar to atomic_inc(), but will saturate at REFCOUNT_SATURATED and WARN. * * Provides no memory ordering, it is assumed the caller already has a * reference on the object. * * Will WARN if the refcount is 0, as this represents a possible use-after-free * condition. */ static inline void refcount_inc(refcount_t *r) { __refcount_inc(r, NULL); } static inline __must_check bool __refcount_sub_and_test(int i, refcount_t *r, int *oldp) { int old = atomic_fetch_sub_release(i, &r->refs); if (oldp) *oldp = old; if (old == i) { smp_acquire__after_ctrl_dep(); return true; } if (unlikely(old < 0 || old - i < 0)) refcount_warn_saturate(r, REFCOUNT_SUB_UAF); return false; } /** * refcount_sub_and_test - subtract from a refcount and test if it is 0 * @i: amount to subtract from the refcount * @r: the refcount * * Similar to atomic_dec_and_test(), but it will WARN, return false and * ultimately leak on underflow and will fail to decrement when saturated * at REFCOUNT_SATURATED. * * Provides release memory ordering, such that prior loads and stores are done * before, and provides an acquire ordering on success such that free() * must come after. * * Use of this function is not recommended for the normal reference counting * use case in which references are taken and released one at a time. In these * cases, refcount_dec(), or one of its variants, should instead be used to * decrement a reference count. * * Return: true if the resulting refcount is 0, false otherwise */ static inline __must_check bool refcount_sub_and_test(int i, refcount_t *r) { return __refcount_sub_and_test(i, r, NULL); } static inline __must_check bool __refcount_dec_and_test(refcount_t *r, int *oldp) { return __refcount_sub_and_test(1, r, oldp); } /** * refcount_dec_and_test - decrement a refcount and test if it is 0 * @r: the refcount * * Similar to atomic_dec_and_test(), it will WARN on underflow and fail to * decrement when saturated at REFCOUNT_SATURATED. * * Provides release memory ordering, such that prior loads and stores are done * before, and provides an acquire ordering on success such that free() * must come after. * * Return: true if the resulting refcount is 0, false otherwise */ static inline __must_check bool refcount_dec_and_test(refcount_t *r) { return __refcount_dec_and_test(r, NULL); } static inline void __refcount_dec(refcount_t *r, int *oldp) { int old = atomic_fetch_sub_release(1, &r->refs); if (oldp) *oldp = old; if (unlikely(old <= 1)) refcount_warn_saturate(r, REFCOUNT_DEC_LEAK); } /** * refcount_dec - decrement a refcount * @r: the refcount * * Similar to atomic_dec(), it will WARN on underflow and fail to decrement * when saturated at REFCOUNT_SATURATED. * * Provides release memory ordering, such that prior loads and stores are done * before. */ static inline void refcount_dec(refcount_t *r) { __refcount_dec(r, NULL); } extern __must_check bool refcount_dec_if_one(refcount_t *r); extern __must_check bool refcount_dec_not_one(refcount_t *r); extern __must_check bool refcount_dec_and_mutex_lock(refcount_t *r, struct mutex *lock); extern __must_check bool refcount_dec_and_lock(refcount_t *r, spinlock_t *lock); extern __must_check bool refcount_dec_and_lock_irqsave(refcount_t *r, spinlock_t *lock, unsigned long *flags); #endif /* _LINUX_REFCOUNT_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 /* SPDX-License-Identifier: GPL-2.0 */ #ifndef _LINUX_NSPROXY_H #define _LINUX_NSPROXY_H #include <linux/spinlock.h> #include <linux/sched.h> struct mnt_namespace; struct uts_namespace; struct ipc_namespace; struct pid_namespace; struct cgroup_namespace; struct fs_struct; /* * A structure to contain pointers to all per-process * namespaces - fs (mount), uts, network, sysvipc, etc. * * The pid namespace is an exception -- it's accessed using * task_active_pid_ns. The pid namespace here is the * namespace that children will use. * * 'count' is the number of tasks holding a reference. * The count for each namespace, then, will be the number * of nsproxies pointing to it, not the number of tasks. * * The nsproxy is shared by tasks which share all namespaces. * As soon as a single namespace is cloned or unshared, the * nsproxy is copied. */ struct nsproxy { atomic_t count; struct uts_namespace *uts_ns; struct ipc_namespace *ipc_ns; struct mnt_namespace *mnt_ns; struct pid_namespace *pid_ns_for_children; struct net *net_ns; struct time_namespace *time_ns; struct time_namespace *time_ns_for_children; struct cgroup_namespace *cgroup_ns; }; extern struct nsproxy init_nsproxy; /* * A structure to encompass all bits needed to install * a partial or complete new set of namespaces. * * If a new user namespace is requested cred will * point to a modifiable set of credentials. If a pointer * to a modifiable set is needed nsset_cred() must be * used and tested. */ struct nsset { unsigned flags; struct nsproxy *nsproxy; struct fs_struct *fs; const struct cred *cred; }; static inline struct cred *nsset_cred(struct nsset *set) { if (set->flags & CLONE_NEWUSER) return (struct cred *)set->cred; return NULL; } /* * the namespaces access rules are: * * 1. only current task is allowed to change tsk->nsproxy pointer or * any pointer on the nsproxy itself. Current must hold the task_lock * when changing tsk->nsproxy. * * 2. when accessing (i.e. reading) current task's namespaces - no * precautions should be taken - just dereference the pointers * * 3. the access to other task namespaces is performed like this * task_lock(task); * nsproxy = task->nsproxy; * if (nsproxy != NULL) { * / * * * work with the namespaces here * * e.g. get the reference on one of them * * / * } / * * * NULL task->nsproxy means that this task is * * almost dead (zombie) * * / * task_unlock(task); * */ int copy_namespaces(unsigned long flags, struct task_struct *tsk); void exit_task_namespaces(struct task_struct *tsk); void switch_task_namespaces(struct task_struct *tsk, struct nsproxy *new); void free_nsproxy(struct nsproxy *ns); int unshare_nsproxy_namespaces(unsigned long, struct nsproxy **, struct cred *, struct fs_struct *); int __init nsproxy_cache_init(void); static inline void put_nsproxy(struct nsproxy *ns) { if (atomic_dec_and_test(&ns->count)) { free_nsproxy(ns); } } static inline void get_nsproxy(struct nsproxy *ns) { atomic_inc(&ns->count); } #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 /* SPDX-License-Identifier: GPL-2.0 */ /* * descriptor table internals; you almost certainly want file.h instead. */ #ifndef __LINUX_FDTABLE_H #define __LINUX_FDTABLE_H #include <linux/posix_types.h> #include <linux/compiler.h> #include <linux/spinlock.h> #include <linux/rcupdate.h> #include <linux/nospec.h> #include <linux/types.h> #include <linux/init.h> #include <linux/fs.h> #include <linux/atomic.h> /* * The default fd array needs to be at least BITS_PER_LONG, * as this is the granularity returned by copy_fdset(). */ #define NR_OPEN_DEFAULT BITS_PER_LONG #define NR_OPEN_MAX ~0U struct fdtable { unsigned int max_fds; struct file __rcu **fd; /* current fd array */ unsigned long *close_on_exec; unsigned long *open_fds; unsigned long *full_fds_bits; struct rcu_head rcu; }; static inline bool close_on_exec(unsigned int fd, const struct fdtable *fdt) { return test_bit(fd, fdt->close_on_exec); } static inline bool fd_is_open(unsigned int fd, const struct fdtable *fdt) { return test_bit(fd, fdt->open_fds); } /* * Open file table structure */ struct files_struct { /* * read mostly part */ atomic_t count; bool resize_in_progress; wait_queue_head_t resize_wait; struct fdtable __rcu *fdt; struct fdtable fdtab; /* * written part on a separate cache line in SMP */ spinlock_t file_lock ____cacheline_aligned_in_smp; unsigned int next_fd; unsigned long close_on_exec_init[1]; unsigned long open_fds_init[1]; unsigned long full_fds_bits_init[1]; struct file __rcu * fd_array[NR_OPEN_DEFAULT]; }; struct file_operations; struct vfsmount; struct dentry; #define rcu_dereference_check_fdtable(files, fdtfd) \ rcu_dereference_check((fdtfd), lockdep_is_held(&(files)->file_lock)) #define files_fdtable(files) \ rcu_dereference_check_fdtable((files), (files)->fdt) /* * The caller must ensure that fd table isn't shared or hold rcu or file lock */ static inline struct file *__fcheck_files(struct files_struct *files, unsigned int fd) { struct fdtable *fdt = rcu_dereference_raw(files->fdt); if (fd < fdt->max_fds) { fd = array_index_nospec(fd, fdt->max_fds); return rcu_dereference_raw(fdt->fd[fd]); } return NULL; } static inline struct file *fcheck_files(struct files_struct *files, unsigned int fd) { RCU_LOCKDEP_WARN(!rcu_read_lock_held() && !lockdep_is_held(&files->file_lock), "suspicious rcu_dereference_check() usage"); return __fcheck_files(files, fd); } /* * Check whether the specified fd has an open file. */ #define fcheck(fd) fcheck_files(current->files, fd) struct task_struct; struct files_struct *get_files_struct(struct task_struct *); void put_files_struct(struct files_struct *fs); void reset_files_struct(struct files_struct *); int unshare_files(struct files_struct **); struct files_struct *dup_fd(struct files_struct *, unsigned, int *) __latent_entropy; void do_close_on_exec(struct files_struct *); int iterate_fd(struct files_struct *, unsigned, int (*)(const void *, struct file *, unsigned), const void *); extern int __alloc_fd(struct files_struct *files, unsigned start, unsigned end, unsigned flags); extern void __fd_install(struct files_struct *files, unsigned int fd, struct file *file); extern int __close_fd(struct files_struct *files, unsigned int fd); extern int __close_range(unsigned int fd, unsigned int max_fd, unsigned int flags); extern int __close_fd_get_file(unsigned int fd, struct file **res); extern int unshare_fd(unsigned long unshare_flags, unsigned int max_fds, struct files_struct **new_fdp); extern struct kmem_cache *files_cachep; #endif /* __LINUX_FDTABLE_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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 /* SPDX-License-Identifier: GPL-2.0-or-later */ /* * Definitions for the 'struct ptr_ring' datastructure. * * Author: * Michael S. Tsirkin <mst@redhat.com> * * Copyright (C) 2016 Red Hat, Inc. * * This is a limited-size FIFO maintaining pointers in FIFO order, with * one CPU producing entries and another consuming entries from a FIFO. * * This implementation tries to minimize cache-contention when there is a * single producer and a single consumer CPU. */ #ifndef _LINUX_PTR_RING_H #define _LINUX_PTR_RING_H 1 #ifdef __KERNEL__ #include <linux/spinlock.h> #include <linux/cache.h> #include <linux/types.h> #include <linux/compiler.h> #include <linux/slab.h> #include <linux/mm.h> #include <asm/errno.h> #endif struct ptr_ring { int producer ____cacheline_aligned_in_smp; spinlock_t producer_lock; int consumer_head ____cacheline_aligned_in_smp; /* next valid entry */ int consumer_tail; /* next entry to invalidate */ spinlock_t consumer_lock; /* Shared consumer/producer data */ /* Read-only by both the producer and the consumer */ int size ____cacheline_aligned_in_smp; /* max entries in queue */ int batch; /* number of entries to consume in a batch */ void **queue; }; /* Note: callers invoking this in a loop must use a compiler barrier, * for example cpu_relax(). * * NB: this is unlike __ptr_ring_empty in that callers must hold producer_lock: * see e.g. ptr_ring_full. */ static inline bool __ptr_ring_full(struct ptr_ring *r) { return r->queue[r->producer]; } static inline bool ptr_ring_full(struct ptr_ring *r) { bool ret; spin_lock(&r->producer_lock); ret = __ptr_ring_full(r); spin_unlock(&r->producer_lock); return ret; } static inline bool ptr_ring_full_irq(struct ptr_ring *r) { bool ret; spin_lock_irq(&r->producer_lock); ret = __ptr_ring_full(r); spin_unlock_irq(&r->producer_lock); return ret; } static inline bool ptr_ring_full_any(struct ptr_ring *r) { unsigned long flags; bool ret; spin_lock_irqsave(&r->producer_lock, flags); ret = __ptr_ring_full(r); spin_unlock_irqrestore(&r->producer_lock, flags); return ret; } static inline bool ptr_ring_full_bh(struct ptr_ring *r) { bool ret; spin_lock_bh(&r->producer_lock); ret = __ptr_ring_full(r); spin_unlock_bh(&r->producer_lock); return ret; } /* Note: callers invoking this in a loop must use a compiler barrier, * for example cpu_relax(). Callers must hold producer_lock. * Callers are responsible for making sure pointer that is being queued * points to a valid data. */ static inline int __ptr_ring_produce(struct ptr_ring *r, void *ptr) { if (unlikely(!r->size) || r->queue[r->producer]) return -ENOSPC; /* Make sure the pointer we are storing points to a valid data. */ /* Pairs with the dependency ordering in __ptr_ring_consume. */ smp_wmb(); WRITE_ONCE(r->queue[r->producer++], ptr); if (unlikely(r->producer >= r->size)) r->producer = 0; return 0; } /* * Note: resize (below) nests producer lock within consumer lock, so if you * consume in interrupt or BH context, you must disable interrupts/BH when * calling this. */ static inline int ptr_ring_produce(struct ptr_ring *r, void *ptr) { int ret; spin_lock(&r->producer_lock); ret = __ptr_ring_produce(r, ptr); spin_unlock(&r->producer_lock); return ret; } static inline int ptr_ring_produce_irq(struct ptr_ring *r, void *ptr) { int ret; spin_lock_irq(&r->producer_lock); ret = __ptr_ring_produce(r, ptr); spin_unlock_irq(&r->producer_lock); return ret; } static inline int ptr_ring_produce_any(struct ptr_ring *r, void *ptr) { unsigned long flags; int ret; spin_lock_irqsave(&r->producer_lock, flags); ret = __ptr_ring_produce(r, ptr); spin_unlock_irqrestore(&r->producer_lock, flags); return ret; } static inline int ptr_ring_produce_bh(struct ptr_ring *r, void *ptr) { int ret; spin_lock_bh(&r->producer_lock); ret = __ptr_ring_produce(r, ptr); spin_unlock_bh(&r->producer_lock); return ret; } static inline void *__ptr_ring_peek(struct ptr_ring *r) { if (likely(r->size)) return READ_ONCE(r->queue[r->consumer_head]); return NULL; } /* * Test ring empty status without taking any locks. * * NB: This is only safe to call if ring is never resized. * * However, if some other CPU consumes ring entries at the same time, the value * returned is not guaranteed to be correct. * * In this case - to avoid incorrectly detecting the ring * as empty - the CPU consuming the ring entries is responsible * for either consuming all ring entries until the ring is empty, * or synchronizing with some other CPU and causing it to * re-test __ptr_ring_empty and/or consume the ring enteries * after the synchronization point. * * Note: callers invoking this in a loop must use a compiler barrier, * for example cpu_relax(). */ static inline bool __ptr_ring_empty(struct ptr_ring *r) { if (likely(r->size)) return !r->queue[READ_ONCE(r->consumer_head)]; return true; } static inline bool ptr_ring_empty(struct ptr_ring *r) { bool ret; spin_lock(&r->consumer_lock); ret = __ptr_ring_empty(r); spin_unlock(&r->consumer_lock); return ret; } static inline bool ptr_ring_empty_irq(struct ptr_ring *r) { bool ret; spin_lock_irq(&r->consumer_lock); ret = __ptr_ring_empty(r); spin_unlock_irq(&r->consumer_lock); return ret; } static inline bool ptr_ring_empty_any(struct ptr_ring *r) { unsigned long flags; bool ret; spin_lock_irqsave(&r->consumer_lock, flags); ret = __ptr_ring_empty(r); spin_unlock_irqrestore(&r->consumer_lock, flags); return ret; } static inline bool ptr_ring_empty_bh(struct ptr_ring *r) { bool ret; spin_lock_bh(&r->consumer_lock); ret = __ptr_ring_empty(r); spin_unlock_bh(&r->consumer_lock); return ret; } /* Must only be called after __ptr_ring_peek returned !NULL */ static inline void __ptr_ring_discard_one(struct ptr_ring *r) { /* Fundamentally, what we want to do is update consumer * index and zero out the entry so producer can reuse it. * Doing it naively at each consume would be as simple as: * consumer = r->consumer; * r->queue[consumer++] = NULL; * if (unlikely(consumer >= r->size)) * consumer = 0; * r->consumer = consumer; * but that is suboptimal when the ring is full as producer is writing * out new entries in the same cache line. Defer these updates until a * batch of entries has been consumed. */ /* Note: we must keep consumer_head valid at all times for __ptr_ring_empty * to work correctly. */ int consumer_head = r->consumer_head; int head = consumer_head++; /* Once we have processed enough entries invalidate them in * the ring all at once so producer can reuse their space in the ring. * We also do this when we reach end of the ring - not mandatory * but helps keep the implementation simple. */ if (unlikely(consumer_head - r->consumer_tail >= r->batch || consumer_head >= r->size)) { /* Zero out entries in the reverse order: this way we touch the * cache line that producer might currently be reading the last; * producer won't make progress and touch other cache lines * besides the first one until we write out all entries. */ while (likely(head >= r->consumer_tail)) r->queue[head--] = NULL; r->consumer_tail = consumer_head; } if (unlikely(consumer_head >= r->size)) { consumer_head = 0; r->consumer_tail = 0; } /* matching READ_ONCE in __ptr_ring_empty for lockless tests */ WRITE_ONCE(r->consumer_head, consumer_head); } static inline void *__ptr_ring_consume(struct ptr_ring *r) { void *ptr; /* The READ_ONCE in __ptr_ring_peek guarantees that anyone * accessing data through the pointer is up to date. Pairs * with smp_wmb in __ptr_ring_produce. */ ptr = __ptr_ring_peek(r); if (ptr) __ptr_ring_discard_one(r); return ptr; } static inline int __ptr_ring_consume_batched(struct ptr_ring *r, void **array, int n) { void *ptr; int i; for (i = 0; i < n; i++) { ptr = __ptr_ring_consume(r); if (!ptr) break; array[i] = ptr; } return i; } /* * Note: resize (below) nests producer lock within consumer lock, so if you * call this in interrupt or BH context, you must disable interrupts/BH when * producing. */ static inline void *ptr_ring_consume(struct ptr_ring *r) { void *ptr; spin_lock(&r->consumer_lock); ptr = __ptr_ring_consume(r); spin_unlock(&r->consumer_lock); return ptr; } static inline void *ptr_ring_consume_irq(struct ptr_ring *r) { void *ptr; spin_lock_irq(&r->consumer_lock); ptr = __ptr_ring_consume(r); spin_unlock_irq(&r->consumer_lock); return ptr; } static inline void *ptr_ring_consume_any(struct ptr_ring *r) { unsigned long flags; void *ptr; spin_lock_irqsave(&r->consumer_lock, flags); ptr = __ptr_ring_consume(r); spin_unlock_irqrestore(&r->consumer_lock, flags); return ptr; } static inline void *ptr_ring_consume_bh(struct ptr_ring *r) { void *ptr; spin_lock_bh(&r->consumer_lock); ptr = __ptr_ring_consume(r); spin_unlock_bh(&r->consumer_lock); return ptr; } static inline int ptr_ring_consume_batched(struct ptr_ring *r, void **array, int n) { int ret; spin_lock(&r->consumer_lock); ret = __ptr_ring_consume_batched(r, array, n); spin_unlock(&r->consumer_lock); return ret; } static inline int ptr_ring_consume_batched_irq(struct ptr_ring *r, void **array, int n) { int ret; spin_lock_irq(&r->consumer_lock); ret = __ptr_ring_consume_batched(r, array, n); spin_unlock_irq(&r->consumer_lock); return ret; } static inline int ptr_ring_consume_batched_any(struct ptr_ring *r, void **array, int n) { unsigned long flags; int ret; spin_lock_irqsave(&r->consumer_lock, flags); ret = __ptr_ring_consume_batched(r, array, n); spin_unlock_irqrestore(&r->consumer_lock, flags); return ret; } static inline int ptr_ring_consume_batched_bh(struct ptr_ring *r, void **array, int n) { int ret; spin_lock_bh(&r->consumer_lock); ret = __ptr_ring_consume_batched(r, array, n); spin_unlock_bh(&r->consumer_lock); return ret; } /* Cast to structure type and call a function without discarding from FIFO. * Function must return a value. * Callers must take consumer_lock. */ #define __PTR_RING_PEEK_CALL(r, f) ((f)(__ptr_ring_peek(r))) #define PTR_RING_PEEK_CALL(r, f) ({ \ typeof((f)(NULL)) __PTR_RING_PEEK_CALL_v; \ \ spin_lock(&(r)->consumer_lock); \ __PTR_RING_PEEK_CALL_v = __PTR_RING_PEEK_CALL(r, f); \ spin_unlock(&(r)->consumer_lock); \ __PTR_RING_PEEK_CALL_v; \ }) #define PTR_RING_PEEK_CALL_IRQ(r, f) ({ \ typeof((f)(NULL)) __PTR_RING_PEEK_CALL_v; \ \ spin_lock_irq(&(r)->consumer_lock); \ __PTR_RING_PEEK_CALL_v = __PTR_RING_PEEK_CALL(r, f); \ spin_unlock_irq(&(r)->consumer_lock); \ __PTR_RING_PEEK_CALL_v; \ }) #define PTR_RING_PEEK_CALL_BH(r, f) ({ \ typeof((f)(NULL)) __PTR_RING_PEEK_CALL_v; \ \ spin_lock_bh(&(r)->consumer_lock); \ __PTR_RING_PEEK_CALL_v = __PTR_RING_PEEK_CALL(r, f); \ spin_unlock_bh(&(r)->consumer_lock); \ __PTR_RING_PEEK_CALL_v; \ }) #define PTR_RING_PEEK_CALL_ANY(r, f) ({ \ typeof((f)(NULL)) __PTR_RING_PEEK_CALL_v; \ unsigned long __PTR_RING_PEEK_CALL_f;\ \ spin_lock_irqsave(&(r)->consumer_lock, __PTR_RING_PEEK_CALL_f); \ __PTR_RING_PEEK_CALL_v = __PTR_RING_PEEK_CALL(r, f); \ spin_unlock_irqrestore(&(r)->consumer_lock, __PTR_RING_PEEK_CALL_f); \ __PTR_RING_PEEK_CALL_v; \ }) /* Not all gfp_t flags (besides GFP_KERNEL) are allowed. See * documentation for vmalloc for which of them are legal. */ static inline void **__ptr_ring_init_queue_alloc(unsigned int size, gfp_t gfp) { if (size > KMALLOC_MAX_SIZE / sizeof(void *)) return NULL; return kvmalloc_array(size, sizeof(void *), gfp | __GFP_ZERO); } static inline void __ptr_ring_set_size(struct ptr_ring *r, int size) { r->size = size; r->batch = SMP_CACHE_BYTES * 2 / sizeof(*(r->queue)); /* We need to set batch at least to 1 to make logic * in __ptr_ring_discard_one work correctly. * Batching too much (because ring is small) would cause a lot of * burstiness. Needs tuning, for now disable batching. */ if (r->batch > r->size / 2 || !r->batch) r->batch = 1; } static inline int ptr_ring_init(struct ptr_ring *r, int size, gfp_t gfp) { r->queue = __ptr_ring_init_queue_alloc(size, gfp); if (!r->queue) return -ENOMEM; __ptr_ring_set_size(r, size); r->producer = r->consumer_head = r->consumer_tail = 0; spin_lock_init(&r->producer_lock); spin_lock_init(&r->consumer_lock); return 0; } /* * Return entries into ring. Destroy entries that don't fit. * * Note: this is expected to be a rare slow path operation. * * Note: producer lock is nested within consumer lock, so if you * resize you must make sure all uses nest correctly. * In particular if you consume ring in interrupt or BH context, you must * disable interrupts/BH when doing so. */ static inline void ptr_ring_unconsume(struct ptr_ring *r, void **batch, int n, void (*destroy)(void *)) { unsigned long flags; int head; spin_lock_irqsave(&r->consumer_lock, flags); spin_lock(&r->producer_lock); if (!r->size) goto done; /* * Clean out buffered entries (for simplicity). This way following code * can test entries for NULL and if not assume they are valid. */ head = r->consumer_head - 1; while (likely(head >= r->consumer_tail)) r->queue[head--] = NULL; r->consumer_tail = r->consumer_head; /* * Go over entries in batch, start moving head back and copy entries. * Stop when we run into previously unconsumed entries. */ while (n) { head = r->consumer_head - 1; if (head < 0) head = r->size - 1; if (r->queue[head]) { /* This batch entry will have to be destroyed. */ goto done; } r->queue[head] = batch[--n]; r->consumer_tail = head; /* matching READ_ONCE in __ptr_ring_empty for lockless tests */ WRITE_ONCE(r->consumer_head, head); } done: /* Destroy all entries left in the batch. */ while (n) destroy(batch[--n]); spin_unlock(&r->producer_lock); spin_unlock_irqrestore(&r->consumer_lock, flags); } static inline void **__ptr_ring_swap_queue(struct ptr_ring *r, void **queue, int size, gfp_t gfp, void (*destroy)(void *)) { int producer = 0; void **old; void *ptr; while ((ptr = __ptr_ring_consume(r))) if (producer < size) queue[producer++] = ptr; else if (destroy) destroy(ptr); if (producer >= size) producer = 0; __ptr_ring_set_size(r, size); r->producer = producer; r->consumer_head = 0; r->consumer_tail = 0; old = r->queue; r->queue = queue; return old; } /* * Note: producer lock is nested within consumer lock, so if you * resize you must make sure all uses nest correctly. * In particular if you consume ring in interrupt or BH context, you must * disable interrupts/BH when doing so. */ static inline int ptr_ring_resize(struct ptr_ring *r, int size, gfp_t gfp, void (*destroy)(void *)) { unsigned long flags; void **queue = __ptr_ring_init_queue_alloc(size, gfp); void **old; if (!queue) return -ENOMEM; spin_lock_irqsave(&(r)->consumer_lock, flags); spin_lock(&(r)->producer_lock); old = __ptr_ring_swap_queue(r, queue, size, gfp, destroy); spin_unlock(&(r)->producer_lock); spin_unlock_irqrestore(&(r)->consumer_lock, flags); kvfree(old); return 0; } /* * Note: producer lock is nested within consumer lock, so if you * resize you must make sure all uses nest correctly. * In particular if you consume ring in interrupt or BH context, you must * disable interrupts/BH when doing so. */ static inline int ptr_ring_resize_multiple(struct ptr_ring **rings, unsigned int nrings, int size, gfp_t gfp, void (*destroy)(void *)) { unsigned long flags; void ***queues; int i; queues = kmalloc_array(nrings, sizeof(*queues), gfp); if (!queues) goto noqueues; for (i = 0; i < nrings; ++i) { queues[i] = __ptr_ring_init_queue_alloc(size, gfp); if (!queues[i]) goto nomem; } for (i = 0; i < nrings; ++i) { spin_lock_irqsave(&(rings[i])->consumer_lock, flags); spin_lock(&(rings[i])->producer_lock); queues[i] = __ptr_ring_swap_queue(rings[i], queues[i], size, gfp, destroy); spin_unlock(&(rings[i])->producer_lock); spin_unlock_irqrestore(&(rings[i])->consumer_lock, flags); } for (i = 0; i < nrings; ++i) kvfree(queues[i]); kfree(queues); return 0; nomem: while (--i >= 0) kvfree(queues[i]); kfree(queues); noqueues: return -ENOMEM; } static inline void ptr_ring_cleanup(struct ptr_ring *r, void (*destroy)(void *)) { void *ptr; if (destroy) while ((ptr = ptr_ring_consume(r))) destroy(ptr); kvfree(r->queue); } #endif /* _LINUX_PTR_RING_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 /* SPDX-License-Identifier: GPL-2.0 */ /* * fs-verity: read-only file-based authenticity protection * * This header declares the interface between the fs/verity/ support layer and * filesystems that support fs-verity. * * Copyright 2019 Google LLC */ #ifndef _LINUX_FSVERITY_H #define _LINUX_FSVERITY_H #include <linux/fs.h> #include <uapi/linux/fsverity.h> /* Verity operations for filesystems */ struct fsverity_operations { /** * Begin enabling verity on the given file. * * @filp: a readonly file descriptor for the file * * The filesystem must do any needed filesystem-specific preparations * for enabling verity, e.g. evicting inline data. It also must return * -EBUSY if verity is already being enabled on the given file. * * i_rwsem is held for write. * * Return: 0 on success, -errno on failure */ int (*begin_enable_verity)(struct file *filp); /** * End enabling verity on the given file. * * @filp: a readonly file descriptor for the file * @desc: the verity descriptor to write, or NULL on failure * @desc_size: size of verity descriptor, or 0 on failure * @merkle_tree_size: total bytes the Merkle tree took up * * If desc == NULL, then enabling verity failed and the filesystem only * must do any necessary cleanups. Else, it must also store the given * verity descriptor to a fs-specific location associated with the inode * and do any fs-specific actions needed to mark the inode as a verity * inode, e.g. setting a bit in the on-disk inode. The filesystem is * also responsible for setting the S_VERITY flag in the VFS inode. * * i_rwsem is held for write, but it may have been dropped between * ->begin_enable_verity() and ->end_enable_verity(). * * Return: 0 on success, -errno on failure */ int (*end_enable_verity)(struct file *filp, const void *desc, size_t desc_size, u64 merkle_tree_size); /** * Get the verity descriptor of the given inode. * * @inode: an inode with the S_VERITY flag set * @buf: buffer in which to place the verity descriptor * @bufsize: size of @buf, or 0 to retrieve the size only * * If bufsize == 0, then the size of the verity descriptor is returned. * Otherwise the verity descriptor is written to 'buf' and its actual * size is returned; -ERANGE is returned if it's too large. This may be * called by multiple processes concurrently on the same inode. * * Return: the size on success, -errno on failure */ int (*get_verity_descriptor)(struct inode *inode, void *buf, size_t bufsize); /** * Read a Merkle tree page of the given inode. * * @inode: the inode * @index: 0-based index of the page within the Merkle tree * @num_ra_pages: The number of Merkle tree pages that should be * prefetched starting at @index if the page at @index * isn't already cached. Implementations may ignore this * argument; it's only a performance optimization. * * This can be called at any time on an open verity file, as well as * between ->begin_enable_verity() and ->end_enable_verity(). It may be * called by multiple processes concurrently, even with the same page. * * Note that this must retrieve a *page*, not necessarily a *block*. * * Return: the page on success, ERR_PTR() on failure */ struct page *(*read_merkle_tree_page)(struct inode *inode, pgoff_t index, unsigned long num_ra_pages); /** * Write a Merkle tree block to the given inode. * * @inode: the inode for which the Merkle tree is being built * @buf: block to write * @index: 0-based index of the block within the Merkle tree * @log_blocksize: log base 2 of the Merkle tree block size * * This is only called between ->begin_enable_verity() and * ->end_enable_verity(). * * Return: 0 on success, -errno on failure */ int (*write_merkle_tree_block)(struct inode *inode, const void *buf, u64 index, int log_blocksize); }; #ifdef CONFIG_FS_VERITY static inline struct fsverity_info *fsverity_get_info(const struct inode *inode) { /* * Pairs with the cmpxchg_release() in fsverity_set_info(). * I.e., another task may publish ->i_verity_info concurrently, * executing a RELEASE barrier. We need to use smp_load_acquire() here * to safely ACQUIRE the memory the other task published. */ return smp_load_acquire(&inode->i_verity_info); } /* enable.c */ int fsverity_ioctl_enable(struct file *filp, const void __user *arg); /* measure.c */ int fsverity_ioctl_measure(struct file *filp, void __user *arg); /* open.c */ int fsverity_file_open(struct inode *inode, struct file *filp); int fsverity_prepare_setattr(struct dentry *dentry, struct iattr *attr); void fsverity_cleanup_inode(struct inode *inode); /* verify.c */ bool fsverity_verify_page(struct page *page); void fsverity_verify_bio(struct bio *bio); void fsverity_enqueue_verify_work(struct work_struct *work); #else /* !CONFIG_FS_VERITY */ static inline struct fsverity_info *fsverity_get_info(const struct inode *inode) { return NULL; } /* enable.c */ static inline int fsverity_ioctl_enable(struct file *filp, const void __user *arg) { return -EOPNOTSUPP; } /* measure.c */ static inline int fsverity_ioctl_measure(struct file *filp, void __user *arg) { return -EOPNOTSUPP; } /* open.c */ static inline int fsverity_file_open(struct inode *inode, struct file *filp) { return IS_VERITY(inode) ? -EOPNOTSUPP : 0; } static inline int fsverity_prepare_setattr(struct dentry *dentry, struct iattr *attr) { return IS_VERITY(d_inode(dentry)) ? -EOPNOTSUPP : 0; } static inline void fsverity_cleanup_inode(struct inode *inode) { } /* verify.c */ static inline bool fsverity_verify_page(struct page *page) { WARN_ON(1); return false; } static inline void fsverity_verify_bio(struct bio *bio) { WARN_ON(1); } static inline void fsverity_enqueue_verify_work(struct work_struct *work) { WARN_ON(1); } #endif /* !CONFIG_FS_VERITY */ /** * fsverity_active() - do reads from the inode need to go through fs-verity? * @inode: inode to check * * This checks whether ->i_verity_info has been set. * * Filesystems call this from ->readpages() to check whether the pages need to * be verified or not. Don't use IS_VERITY() for this purpose; it's subject to * a race condition where the file is being read concurrently with * FS_IOC_ENABLE_VERITY completing. (S_VERITY is set before ->i_verity_info.) * * Return: true if reads need to go through fs-verity, otherwise false */ static inline bool fsverity_active(const struct inode *inode) { return fsverity_get_info(inode) != NULL; } #endif /* _LINUX_FSVERITY_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 #ifndef _LINUX_GENERIC_RADIX_TREE_H #define _LINUX_GENERIC_RADIX_TREE_H /** * DOC: Generic radix trees/sparse arrays * * Very simple and minimalistic, supporting arbitrary size entries up to * PAGE_SIZE. * * A genradix is defined with the type it will store, like so: * * static GENRADIX(struct foo) foo_genradix; * * The main operations are: * * - genradix_init(radix) - initialize an empty genradix * * - genradix_free(radix) - free all memory owned by the genradix and * reinitialize it * * - genradix_ptr(radix, idx) - gets a pointer to the entry at idx, returning * NULL if that entry does not exist * * - genradix_ptr_alloc(radix, idx, gfp) - gets a pointer to an entry, * allocating it if necessary * * - genradix_for_each(radix, iter, p) - iterate over each entry in a genradix * * The radix tree allocates one page of entries at a time, so entries may exist * that were never explicitly allocated - they will be initialized to all * zeroes. * * Internally, a genradix is just a radix tree of pages, and indexing works in * terms of byte offsets. The wrappers in this header file use sizeof on the * type the radix contains to calculate a byte offset from the index - see * __idx_to_offset. */ #include <asm/page.h> #include <linux/bug.h> #include <linux/kernel.h> #include <linux/log2.h> struct genradix_root; struct __genradix { struct genradix_root *root; }; /* * NOTE: currently, sizeof(_type) must not be larger than PAGE_SIZE: */ #define __GENRADIX_INITIALIZER \ { \ .tree = { \ .root = NULL, \ } \ } /* * We use a 0 size array to stash the type we're storing without taking any * space at runtime - then the various accessor macros can use typeof() to get * to it for casts/sizeof - we also force the alignment so that storing a type * with a ridiculous alignment doesn't blow up the alignment or size of the * genradix. */ #define GENRADIX(_type) \ struct { \ struct __genradix tree; \ _type type[0] __aligned(1); \ } #define DEFINE_GENRADIX(_name, _type) \ GENRADIX(_type) _name = __GENRADIX_INITIALIZER /** * genradix_init - initialize a genradix * @_radix: genradix to initialize * * Does not fail */ #define genradix_init(_radix) \ do { \ *(_radix) = (typeof(*_radix)) __GENRADIX_INITIALIZER; \ } while (0) void __genradix_free(struct __genradix *); /** * genradix_free: free all memory owned by a genradix * @_radix: the genradix to free * * After freeing, @_radix will be reinitialized and empty */ #define genradix_free(_radix) __genradix_free(&(_radix)->tree) static inline size_t __idx_to_offset(size_t idx, size_t obj_size) { if (__builtin_constant_p(obj_size)) BUILD_BUG_ON(obj_size > PAGE_SIZE); else BUG_ON(obj_size > PAGE_SIZE); if (!is_power_of_2(obj_size)) { size_t objs_per_page = PAGE_SIZE / obj_size; return (idx / objs_per_page) * PAGE_SIZE + (idx % objs_per_page) * obj_size; } else { return idx * obj_size; } } #define __genradix_cast(_radix) (typeof((_radix)->type[0]) *) #define __genradix_obj_size(_radix) sizeof((_radix)->type[0]) #define __genradix_idx_to_offset(_radix, _idx) \ __idx_to_offset(_idx, __genradix_obj_size(_radix)) void *__genradix_ptr(struct __genradix *, size_t); /** * genradix_ptr - get a pointer to a genradix entry * @_radix: genradix to access * @_idx: index to fetch * * Returns a pointer to entry at @_idx, or NULL if that entry does not exist. */ #define genradix_ptr(_radix, _idx) \ (__genradix_cast(_radix) \ __genradix_ptr(&(_radix)->tree, \ __genradix_idx_to_offset(_radix, _idx))) void *__genradix_ptr_alloc(struct __genradix *, size_t, gfp_t); /** * genradix_ptr_alloc - get a pointer to a genradix entry, allocating it * if necessary * @_radix: genradix to access * @_idx: index to fetch * @_gfp: gfp mask * * Returns a pointer to entry at @_idx, or NULL on allocation failure */ #define genradix_ptr_alloc(_radix, _idx, _gfp) \ (__genradix_cast(_radix) \ __genradix_ptr_alloc(&(_radix)->tree, \ __genradix_idx_to_offset(_radix, _idx), \ _gfp)) struct genradix_iter { size_t offset; size_t pos; }; /** * genradix_iter_init - initialize a genradix_iter * @_radix: genradix that will be iterated over * @_idx: index to start iterating from */ #define genradix_iter_init(_radix, _idx) \ ((struct genradix_iter) { \ .pos = (_idx), \ .offset = __genradix_idx_to_offset((_radix), (_idx)),\ }) void *__genradix_iter_peek(struct genradix_iter *, struct __genradix *, size_t); /** * genradix_iter_peek - get first entry at or above iterator's current * position * @_iter: a genradix_iter * @_radix: genradix being iterated over * * If no more entries exist at or above @_iter's current position, returns NULL */ #define genradix_iter_peek(_iter, _radix) \ (__genradix_cast(_radix) \ __genradix_iter_peek(_iter, &(_radix)->tree, \ PAGE_SIZE / __genradix_obj_size(_radix))) static inline void __genradix_iter_advance(struct genradix_iter *iter, size_t obj_size) { iter->offset += obj_size; if (!is_power_of_2(obj_size) && (iter->offset & (PAGE_SIZE - 1)) + obj_size > PAGE_SIZE) iter->offset = round_up(iter->offset, PAGE_SIZE); iter->pos++; } #define genradix_iter_advance(_iter, _radix) \ __genradix_iter_advance(_iter, __genradix_obj_size(_radix)) #define genradix_for_each_from(_radix, _iter, _p, _start) \ for (_iter = genradix_iter_init(_radix, _start); \ (_p = genradix_iter_peek(&_iter, _radix)) != NULL; \ genradix_iter_advance(&_iter, _radix)) /** * genradix_for_each - iterate over entry in a genradix * @_radix: genradix to iterate over * @_iter: a genradix_iter to track current position * @_p: pointer to genradix entry type * * On every iteration, @_p will point to the current entry, and @_iter.pos * will be the current entry's index. */ #define genradix_for_each(_radix, _iter, _p) \ genradix_for_each_from(_radix, _iter, _p, 0) int __genradix_prealloc(struct __genradix *, size_t, gfp_t); /** * genradix_prealloc - preallocate entries in a generic radix tree * @_radix: genradix to preallocate * @_nr: number of entries to preallocate * @_gfp: gfp mask * * Returns 0 on success, -ENOMEM on failure */ #define genradix_prealloc(_radix, _nr, _gfp) \ __genradix_prealloc(&(_radix)->tree, \ __genradix_idx_to_offset(_radix, _nr + 1),\ _gfp) #endif /* _LINUX_GENERIC_RADIX_TREE_H */
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1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 // SPDX-License-Identifier: GPL-2.0 /* * linux/fs/file.c * * Copyright (C) 1998-1999, Stephen Tweedie and Bill Hawes * * Manage the dynamic fd arrays in the process files_struct. */ #include <linux/syscalls.h> #include <linux/export.h> #include <linux/fs.h> #include <linux/kernel.h> #include <linux/mm.h> #include <linux/sched/signal.h> #include <linux/slab.h> #include <linux/file.h> #include <linux/fdtable.h> #include <linux/bitops.h> #include <linux/spinlock.h> #include <linux/rcupdate.h> #include <linux/close_range.h> #include <net/sock.h> unsigned int sysctl_nr_open __read_mostly = 1024*1024; unsigned int sysctl_nr_open_min = BITS_PER_LONG; /* our min() is unusable in constant expressions ;-/ */ #define __const_min(x, y) ((x) < (y) ? (x) : (y)) unsigned int sysctl_nr_open_max = __const_min(INT_MAX, ~(size_t)0/sizeof(void *)) & -BITS_PER_LONG; static void __free_fdtable(struct fdtable *fdt) { kvfree(fdt->fd); kvfree(fdt->open_fds); kfree(fdt); } static void free_fdtable_rcu(struct rcu_head *rcu) { __free_fdtable(container_of(rcu, struct fdtable, rcu)); } #define BITBIT_NR(nr) BITS_TO_LONGS(BITS_TO_LONGS(nr)) #define BITBIT_SIZE(nr) (BITBIT_NR(nr) * sizeof(long)) /* * Copy 'count' fd bits from the old table to the new table and clear the extra * space if any. This does not copy the file pointers. Called with the files * spinlock held for write. */ static void copy_fd_bitmaps(struct fdtable *nfdt, struct fdtable *ofdt, unsigned int count) { unsigned int cpy, set; cpy = count / BITS_PER_BYTE; set = (nfdt->max_fds - count) / BITS_PER_BYTE; memcpy(nfdt->open_fds, ofdt->open_fds, cpy); memset((char *)nfdt->open_fds + cpy, 0, set); memcpy(nfdt->close_on_exec, ofdt->close_on_exec, cpy); memset((char *)nfdt->close_on_exec + cpy, 0, set); cpy = BITBIT_SIZE(count); set = BITBIT_SIZE(nfdt->max_fds) - cpy; memcpy(nfdt->full_fds_bits, ofdt->full_fds_bits, cpy); memset((char *)nfdt->full_fds_bits + cpy, 0, set); } /* * Copy all file descriptors from the old table to the new, expanded table and * clear the extra space. Called with the files spinlock held for write. */ static void copy_fdtable(struct fdtable *nfdt, struct fdtable *ofdt) { size_t cpy, set; BUG_ON(nfdt->max_fds < ofdt->max_fds); cpy = ofdt->max_fds * sizeof(struct file *); set = (nfdt->max_fds - ofdt->max_fds) * sizeof(struct file *); memcpy(nfdt->fd, ofdt->fd, cpy); memset((char *)nfdt->fd + cpy, 0, set); copy_fd_bitmaps(nfdt, ofdt, ofdt->max_fds); } static struct fdtable * alloc_fdtable(unsigned int nr) { struct fdtable *fdt; void *data; /* * Figure out how many fds we actually want to support in this fdtable. * Allocation steps are keyed to the size of the fdarray, since it * grows far faster than any of the other dynamic data. We try to fit * the fdarray into comfortable page-tuned chunks: starting at 1024B * and growing in powers of two from there on. */ nr /= (1024 / sizeof(struct file *)); nr = roundup_pow_of_two(nr + 1); nr *= (1024 / sizeof(struct file *)); /* * Note that this can drive nr *below* what we had passed if sysctl_nr_open * had been set lower between the check in expand_files() and here. Deal * with that in caller, it's cheaper that way. * * We make sure that nr remains a multiple of BITS_PER_LONG - otherwise * bitmaps handling below becomes unpleasant, to put it mildly... */ if (unlikely(nr > sysctl_nr_open)) nr = ((sysctl_nr_open - 1) | (BITS_PER_LONG - 1)) + 1; fdt = kmalloc(sizeof(struct fdtable), GFP_KERNEL_ACCOUNT); if (!fdt) goto out; fdt->max_fds = nr; data = kvmalloc_array(nr, sizeof(struct file *), GFP_KERNEL_ACCOUNT); if (!data) goto out_fdt; fdt->fd = data; data = kvmalloc(max_t(size_t, 2 * nr