1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Filesystem access notification for Linux 4 * 5 * Copyright (C) 2008 Red Hat, Inc., Eric Paris <eparis@redhat.com> 6 */ 7 8 #ifndef __LINUX_FSNOTIFY_BACKEND_H 9 #define __LINUX_FSNOTIFY_BACKEND_H 10 11 #ifdef __KERNEL__ 12 13 #include <linux/idr.h> /* inotify uses this */ 14 #include <linux/fs.h> /* struct inode */ 15 #include <linux/list.h> 16 #include <linux/path.h> /* struct path */ 17 #include <linux/spinlock.h> 18 #include <linux/types.h> 19 #include <linux/atomic.h> 20 #include <linux/user_namespace.h> 21 #include <linux/refcount.h> 22 23 /* 24 * IN_* from inotfy.h lines up EXACTLY with FS_*, this is so we can easily 25 * convert between them. dnotify only needs conversion at watch creation 26 * so no perf loss there. fanotify isn't defined yet, so it can use the 27 * wholes if it needs more events. 28 */ 29 #define FS_ACCESS 0x00000001 /* File was accessed */ 30 #define FS_MODIFY 0x00000002 /* File was modified */ 31 #define FS_ATTRIB 0x00000004 /* Metadata changed */ 32 #define FS_CLOSE_WRITE 0x00000008 /* Writtable file was closed */ 33 #define FS_CLOSE_NOWRITE 0x00000010 /* Unwrittable file closed */ 34 #define FS_OPEN 0x00000020 /* File was opened */ 35 #define FS_MOVED_FROM 0x00000040 /* File was moved from X */ 36 #define FS_MOVED_TO 0x00000080 /* File was moved to Y */ 37 #define FS_CREATE 0x00000100 /* Subfile was created */ 38 #define FS_DELETE 0x00000200 /* Subfile was deleted */ 39 #define FS_DELETE_SELF 0x00000400 /* Self was deleted */ 40 #define FS_MOVE_SELF 0x00000800 /* Self was moved */ 41 #define FS_OPEN_EXEC 0x00001000 /* File was opened for exec */ 42 43 #define FS_UNMOUNT 0x00002000 /* inode on umount fs */ 44 #define FS_Q_OVERFLOW 0x00004000 /* Event queued overflowed */ 45 #define FS_IN_IGNORED 0x00008000 /* last inotify event here */ 46 47 #define FS_OPEN_PERM 0x00010000 /* open event in an permission hook */ 48 #define FS_ACCESS_PERM 0x00020000 /* access event in a permissions hook */ 49 #define FS_OPEN_EXEC_PERM 0x00040000 /* open/exec event in a permission hook */ 50 51 #define FS_EXCL_UNLINK 0x04000000 /* do not send events if object is unlinked */ 52 /* 53 * Set on inode mark that cares about things that happen to its children. 54 * Always set for dnotify and inotify. 55 * Set on inode/sb/mount marks that care about parent/name info. 56 */ 57 #define FS_EVENT_ON_CHILD 0x08000000 58 59 #define FS_DN_RENAME 0x10000000 /* file renamed */ 60 #define FS_DN_MULTISHOT 0x20000000 /* dnotify multishot */ 61 #define FS_ISDIR 0x40000000 /* event occurred against dir */ 62 #define FS_IN_ONESHOT 0x80000000 /* only send event once */ 63 64 #define FS_MOVE (FS_MOVED_FROM | FS_MOVED_TO) 65 66 /* 67 * Directory entry modification events - reported only to directory 68 * where entry is modified and not to a watching parent. 69 * The watching parent may get an FS_ATTRIB|FS_EVENT_ON_CHILD event 70 * when a directory entry inside a child subdir changes. 71 */ 72 #define ALL_FSNOTIFY_DIRENT_EVENTS (FS_CREATE | FS_DELETE | FS_MOVE) 73 74 #define ALL_FSNOTIFY_PERM_EVENTS (FS_OPEN_PERM | FS_ACCESS_PERM | \ 75 FS_OPEN_EXEC_PERM) 76 77 /* 78 * This is a list of all events that may get sent to a parent that is watching 79 * with flag FS_EVENT_ON_CHILD based on fs event on a child of that directory. 80 */ 81 #define FS_EVENTS_POSS_ON_CHILD (ALL_FSNOTIFY_PERM_EVENTS | \ 82 FS_ACCESS | FS_MODIFY | FS_ATTRIB | \ 83 FS_CLOSE_WRITE | FS_CLOSE_NOWRITE | \ 84 FS_OPEN | FS_OPEN_EXEC) 85 86 /* 87 * This is a list of all events that may get sent with the parent inode as the 88 * @to_tell argument of fsnotify(). 89 * It may include events that can be sent to an inode/sb/mount mark, but cannot 90 * be sent to a parent watching children. 91 */ 92 #define FS_EVENTS_POSS_TO_PARENT (FS_EVENTS_POSS_ON_CHILD) 93 94 /* Events that can be reported to backends */ 95 #define ALL_FSNOTIFY_EVENTS (ALL_FSNOTIFY_DIRENT_EVENTS | \ 96 FS_EVENTS_POSS_ON_CHILD | \ 97 FS_DELETE_SELF | FS_MOVE_SELF | FS_DN_RENAME | \ 98 FS_UNMOUNT | FS_Q_OVERFLOW | FS_IN_IGNORED) 99 100 /* Extra flags that may be reported with event or control handling of events */ 101 #define ALL_FSNOTIFY_FLAGS (FS_EXCL_UNLINK | FS_ISDIR | FS_IN_ONESHOT | \ 102 FS_DN_MULTISHOT | FS_EVENT_ON_CHILD) 103 104 #define ALL_FSNOTIFY_BITS (ALL_FSNOTIFY_EVENTS | ALL_FSNOTIFY_FLAGS) 105 106 struct fsnotify_group; 107 struct fsnotify_event; 108 struct fsnotify_mark; 109 struct fsnotify_event_private_data; 110 struct fsnotify_fname; 111 struct fsnotify_iter_info; 112 113 struct mem_cgroup; 114 115 /* 116 * Each group much define these ops. The fsnotify infrastructure will call 117 * these operations for each relevant group. 118 * 119 * handle_event - main call for a group to handle an fs event 120 * @group: group to notify 121 * @mask: event type and flags 122 * @data: object that event happened on 123 * @data_type: type of object for fanotify_data_XXX() accessors 124 * @dir: optional directory associated with event - 125 * if @file_name is not NULL, this is the directory that 126 * @file_name is relative to 127 * @file_name: optional file name associated with event 128 * @cookie: inotify rename cookie 129 * @iter_info: array of marks from this group that are interested in the event 130 * 131 * handle_inode_event - simple variant of handle_event() for groups that only 132 * have inode marks and don't have ignore mask 133 * @mark: mark to notify 134 * @mask: event type and flags 135 * @inode: inode that event happened on 136 * @dir: optional directory associated with event - 137 * if @file_name is not NULL, this is the directory that 138 * @file_name is relative to. 139 * @file_name: optional file name associated with event 140 * @cookie: inotify rename cookie 141 * 142 * free_group_priv - called when a group refcnt hits 0 to clean up the private union 143 * freeing_mark - called when a mark is being destroyed for some reason. The group 144 * MUST be holding a reference on each mark and that reference must be 145 * dropped in this function. inotify uses this function to send 146 * userspace messages that marks have been removed. 147 */ 148 struct fsnotify_ops { 149 int (*handle_event)(struct fsnotify_group *group, u32 mask, 150 const void *data, int data_type, struct inode *dir, 151 const struct qstr *file_name, u32 cookie, 152 struct fsnotify_iter_info *iter_info); 153 int (*handle_inode_event)(struct fsnotify_mark *mark, u32 mask, 154 struct inode *inode, struct inode *dir, 155 const struct qstr *file_name, u32 cookie); 156 void (*free_group_priv)(struct fsnotify_group *group); 157 void (*freeing_mark)(struct fsnotify_mark *mark, struct fsnotify_group *group); 158 void (*free_event)(struct fsnotify_event *event); 159 /* called on final put+free to free memory */ 160 void (*free_mark)(struct fsnotify_mark *mark); 161 }; 162 163 /* 164 * all of the information about the original object we want to now send to 165 * a group. If you want to carry more info from the accessing task to the 166 * listener this structure is where you need to be adding fields. 167 */ 168 struct fsnotify_event { 169 struct list_head list; 170 }; 171 172 /* 173 * A group is a "thing" that wants to receive notification about filesystem 174 * events. The mask holds the subset of event types this group cares about. 175 * refcnt on a group is up to the implementor and at any moment if it goes 0 176 * everything will be cleaned up. 177 */ 178 struct fsnotify_group { 179 const struct fsnotify_ops *ops; /* how this group handles things */ 180 181 /* 182 * How the refcnt is used is up to each group. When the refcnt hits 0 183 * fsnotify will clean up all of the resources associated with this group. 184 * As an example, the dnotify group will always have a refcnt=1 and that 185 * will never change. Inotify, on the other hand, has a group per 186 * inotify_init() and the refcnt will hit 0 only when that fd has been 187 * closed. 188 */ 189 refcount_t refcnt; /* things with interest in this group */ 190 191 /* needed to send notification to userspace */ 192 spinlock_t notification_lock; /* protect the notification_list */ 193 struct list_head notification_list; /* list of event_holder this group needs to send to userspace */ 194 wait_queue_head_t notification_waitq; /* read() on the notification file blocks on this waitq */ 195 unsigned int q_len; /* events on the queue */ 196 unsigned int max_events; /* maximum events allowed on the list */ 197 /* 198 * Valid fsnotify group priorities. Events are send in order from highest 199 * priority to lowest priority. We default to the lowest priority. 200 */ 201 #define FS_PRIO_0 0 /* normal notifiers, no permissions */ 202 #define FS_PRIO_1 1 /* fanotify content based access control */ 203 #define FS_PRIO_2 2 /* fanotify pre-content access */ 204 unsigned int priority; 205 bool shutdown; /* group is being shut down, don't queue more events */ 206 207 /* stores all fastpath marks assoc with this group so they can be cleaned on unregister */ 208 struct mutex mark_mutex; /* protect marks_list */ 209 atomic_t user_waits; /* Number of tasks waiting for user 210 * response */ 211 struct list_head marks_list; /* all inode marks for this group */ 212 213 struct fasync_struct *fsn_fa; /* async notification */ 214 215 struct fsnotify_event *overflow_event; /* Event we queue when the 216 * notification list is too 217 * full */ 218 219 struct mem_cgroup *memcg; /* memcg to charge allocations */ 220 221 /* groups can define private fields here or use the void *private */ 222 union { 223 void *private; 224 #ifdef CONFIG_INOTIFY_USER 225 struct inotify_group_private_data { 226 spinlock_t idr_lock; 227 struct idr idr; 228 struct ucounts *ucounts; 229 } inotify_data; 230 #endif 231 #ifdef CONFIG_FANOTIFY 232 struct fanotify_group_private_data { 233 /* Hash table of events for merge */ 234 struct hlist_head *merge_hash; 235 /* allows a group to block waiting for a userspace response */ 236 struct list_head access_list; 237 wait_queue_head_t access_waitq; 238 int flags; /* flags from fanotify_init() */ 239 int f_flags; /* event_f_flags from fanotify_init() */ 240 struct ucounts *ucounts; 241 } fanotify_data; 242 #endif /* CONFIG_FANOTIFY */ 243 }; 244 }; 245 246 /* When calling fsnotify tell it if the data is a path or inode */ 247 enum fsnotify_data_type { 248 FSNOTIFY_EVENT_NONE, 249 FSNOTIFY_EVENT_PATH, 250 FSNOTIFY_EVENT_INODE, 251 }; 252 253 static inline struct inode *fsnotify_data_inode(const void *data, int data_type) 254 { 255 switch (data_type) { 256 case FSNOTIFY_EVENT_INODE: 257 return (struct inode *)data; 258 case FSNOTIFY_EVENT_PATH: 259 return d_inode(((const struct path *)data)->dentry); 260 default: 261 return NULL; 262 } 263 } 264 265 static inline const struct path *fsnotify_data_path(const void *data, 266 int data_type) 267 { 268 switch (data_type) { 269 case FSNOTIFY_EVENT_PATH: 270 return data; 271 default: 272 return NULL; 273 } 274 } 275 276 enum fsnotify_obj_type { 277 FSNOTIFY_OBJ_TYPE_INODE, 278 FSNOTIFY_OBJ_TYPE_PARENT, 279 FSNOTIFY_OBJ_TYPE_VFSMOUNT, 280 FSNOTIFY_OBJ_TYPE_SB, 281 FSNOTIFY_OBJ_TYPE_COUNT, 282 FSNOTIFY_OBJ_TYPE_DETACHED = FSNOTIFY_OBJ_TYPE_COUNT 283 }; 284 285 #define FSNOTIFY_OBJ_TYPE_INODE_FL (1U << FSNOTIFY_OBJ_TYPE_INODE) 286 #define FSNOTIFY_OBJ_TYPE_PARENT_FL (1U << FSNOTIFY_OBJ_TYPE_PARENT) 287 #define FSNOTIFY_OBJ_TYPE_VFSMOUNT_FL (1U << FSNOTIFY_OBJ_TYPE_VFSMOUNT) 288 #define FSNOTIFY_OBJ_TYPE_SB_FL (1U << FSNOTIFY_OBJ_TYPE_SB) 289 #define FSNOTIFY_OBJ_ALL_TYPES_MASK ((1U << FSNOTIFY_OBJ_TYPE_COUNT) - 1) 290 291 static inline bool fsnotify_valid_obj_type(unsigned int type) 292 { 293 return (type < FSNOTIFY_OBJ_TYPE_COUNT); 294 } 295 296 struct fsnotify_iter_info { 297 struct fsnotify_mark *marks[FSNOTIFY_OBJ_TYPE_COUNT]; 298 unsigned int report_mask; 299 int srcu_idx; 300 }; 301 302 static inline bool fsnotify_iter_should_report_type( 303 struct fsnotify_iter_info *iter_info, int type) 304 { 305 return (iter_info->report_mask & (1U << type)); 306 } 307 308 static inline void fsnotify_iter_set_report_type( 309 struct fsnotify_iter_info *iter_info, int type) 310 { 311 iter_info->report_mask |= (1U << type); 312 } 313 314 static inline void fsnotify_iter_set_report_type_mark( 315 struct fsnotify_iter_info *iter_info, int type, 316 struct fsnotify_mark *mark) 317 { 318 iter_info->marks[type] = mark; 319 iter_info->report_mask |= (1U << type); 320 } 321 322 #define FSNOTIFY_ITER_FUNCS(name, NAME) \ 323 static inline struct fsnotify_mark *fsnotify_iter_##name##_mark( \ 324 struct fsnotify_iter_info *iter_info) \ 325 { \ 326 return (iter_info->report_mask & FSNOTIFY_OBJ_TYPE_##NAME##_FL) ? \ 327 iter_info->marks[FSNOTIFY_OBJ_TYPE_##NAME] : NULL; \ 328 } 329 330 FSNOTIFY_ITER_FUNCS(inode, INODE) 331 FSNOTIFY_ITER_FUNCS(parent, PARENT) 332 FSNOTIFY_ITER_FUNCS(vfsmount, VFSMOUNT) 333 FSNOTIFY_ITER_FUNCS(sb, SB) 334 335 #define fsnotify_foreach_obj_type(type) \ 336 for (type = 0; type < FSNOTIFY_OBJ_TYPE_COUNT; type++) 337 338 /* 339 * fsnotify_connp_t is what we embed in objects which connector can be attached 340 * to. fsnotify_connp_t * is how we refer from connector back to object. 341 */ 342 struct fsnotify_mark_connector; 343 typedef struct fsnotify_mark_connector __rcu *fsnotify_connp_t; 344 345 /* 346 * Inode/vfsmount/sb point to this structure which tracks all marks attached to 347 * the inode/vfsmount/sb. The reference to inode/vfsmount/sb is held by this 348 * structure. We destroy this structure when there are no more marks attached 349 * to it. The structure is protected by fsnotify_mark_srcu. 350 */ 351 struct fsnotify_mark_connector { 352 spinlock_t lock; 353 unsigned short type; /* Type of object [lock] */ 354 #define FSNOTIFY_CONN_FLAG_HAS_FSID 0x01 355 unsigned short flags; /* flags [lock] */ 356 __kernel_fsid_t fsid; /* fsid of filesystem containing object */ 357 union { 358 /* Object pointer [lock] */ 359 fsnotify_connp_t *obj; 360 /* Used listing heads to free after srcu period expires */ 361 struct fsnotify_mark_connector *destroy_next; 362 }; 363 struct hlist_head list; 364 }; 365 366 /* 367 * A mark is simply an object attached to an in core inode which allows an 368 * fsnotify listener to indicate they are either no longer interested in events 369 * of a type matching mask or only interested in those events. 370 * 371 * These are flushed when an inode is evicted from core and may be flushed 372 * when the inode is modified (as seen by fsnotify_access). Some fsnotify 373 * users (such as dnotify) will flush these when the open fd is closed and not 374 * at inode eviction or modification. 375 * 376 * Text in brackets is showing the lock(s) protecting modifications of a 377 * particular entry. obj_lock means either inode->i_lock or 378 * mnt->mnt_root->d_lock depending on the mark type. 379 */ 380 struct fsnotify_mark { 381 /* Mask this mark is for [mark->lock, group->mark_mutex] */ 382 __u32 mask; 383 /* We hold one for presence in g_list. Also one ref for each 'thing' 384 * in kernel that found and may be using this mark. */ 385 refcount_t refcnt; 386 /* Group this mark is for. Set on mark creation, stable until last ref 387 * is dropped */ 388 struct fsnotify_group *group; 389 /* List of marks by group->marks_list. Also reused for queueing 390 * mark into destroy_list when it's waiting for the end of SRCU period 391 * before it can be freed. [group->mark_mutex] */ 392 struct list_head g_list; 393 /* Protects inode / mnt pointers, flags, masks */ 394 spinlock_t lock; 395 /* List of marks for inode / vfsmount [connector->lock, mark ref] */ 396 struct hlist_node obj_list; 397 /* Head of list of marks for an object [mark ref] */ 398 struct fsnotify_mark_connector *connector; 399 /* Events types to ignore [mark->lock, group->mark_mutex] */ 400 __u32 ignored_mask; 401 #define FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY 0x01 402 #define FSNOTIFY_MARK_FLAG_ALIVE 0x02 403 #define FSNOTIFY_MARK_FLAG_ATTACHED 0x04 404 unsigned int flags; /* flags [mark->lock] */ 405 }; 406 407 #ifdef CONFIG_FSNOTIFY 408 409 /* called from the vfs helpers */ 410 411 /* main fsnotify call to send events */ 412 extern int fsnotify(__u32 mask, const void *data, int data_type, 413 struct inode *dir, const struct qstr *name, 414 struct inode *inode, u32 cookie); 415 extern int __fsnotify_parent(struct dentry *dentry, __u32 mask, const void *data, 416 int data_type); 417 extern void __fsnotify_inode_delete(struct inode *inode); 418 extern void __fsnotify_vfsmount_delete(struct vfsmount *mnt); 419 extern void fsnotify_sb_delete(struct super_block *sb); 420 extern u32 fsnotify_get_cookie(void); 421 422 static inline __u32 fsnotify_parent_needed_mask(__u32 mask) 423 { 424 /* FS_EVENT_ON_CHILD is set on marks that want parent/name info */ 425 if (!(mask & FS_EVENT_ON_CHILD)) 426 return 0; 427 /* 428 * This object might be watched by a mark that cares about parent/name 429 * info, does it care about the specific set of events that can be 430 * reported with parent/name info? 431 */ 432 return mask & FS_EVENTS_POSS_TO_PARENT; 433 } 434 435 static inline int fsnotify_inode_watches_children(struct inode *inode) 436 { 437 /* FS_EVENT_ON_CHILD is set if the inode may care */ 438 if (!(inode->i_fsnotify_mask & FS_EVENT_ON_CHILD)) 439 return 0; 440 /* this inode might care about child events, does it care about the 441 * specific set of events that can happen on a child? */ 442 return inode->i_fsnotify_mask & FS_EVENTS_POSS_ON_CHILD; 443 } 444 445 /* 446 * Update the dentry with a flag indicating the interest of its parent to receive 447 * filesystem events when those events happens to this dentry->d_inode. 448 */ 449 static inline void fsnotify_update_flags(struct dentry *dentry) 450 { 451 assert_spin_locked(&dentry->d_lock); 452 453 /* 454 * Serialisation of setting PARENT_WATCHED on the dentries is provided 455 * by d_lock. If inotify_inode_watched changes after we have taken 456 * d_lock, the following __fsnotify_update_child_dentry_flags call will 457 * find our entry, so it will spin until we complete here, and update 458 * us with the new state. 459 */ 460 if (fsnotify_inode_watches_children(dentry->d_parent->d_inode)) 461 dentry->d_flags |= DCACHE_FSNOTIFY_PARENT_WATCHED; 462 else 463 dentry->d_flags &= ~DCACHE_FSNOTIFY_PARENT_WATCHED; 464 } 465 466 /* called from fsnotify listeners, such as fanotify or dnotify */ 467 468 /* create a new group */ 469 extern struct fsnotify_group *fsnotify_alloc_group(const struct fsnotify_ops *ops); 470 extern struct fsnotify_group *fsnotify_alloc_user_group(const struct fsnotify_ops *ops); 471 /* get reference to a group */ 472 extern void fsnotify_get_group(struct fsnotify_group *group); 473 /* drop reference on a group from fsnotify_alloc_group */ 474 extern void fsnotify_put_group(struct fsnotify_group *group); 475 /* group destruction begins, stop queuing new events */ 476 extern void fsnotify_group_stop_queueing(struct fsnotify_group *group); 477 /* destroy group */ 478 extern void fsnotify_destroy_group(struct fsnotify_group *group); 479 /* fasync handler function */ 480 extern int fsnotify_fasync(int fd, struct file *file, int on); 481 /* Free event from memory */ 482 extern void fsnotify_destroy_event(struct fsnotify_group *group, 483 struct fsnotify_event *event); 484 /* attach the event to the group notification queue */ 485 extern int fsnotify_add_event(struct fsnotify_group *group, 486 struct fsnotify_event *event, 487 int (*merge)(struct fsnotify_group *, 488 struct fsnotify_event *), 489 void (*insert)(struct fsnotify_group *, 490 struct fsnotify_event *)); 491 /* Queue overflow event to a notification group */ 492 static inline void fsnotify_queue_overflow(struct fsnotify_group *group) 493 { 494 fsnotify_add_event(group, group->overflow_event, NULL, NULL); 495 } 496 497 static inline bool fsnotify_notify_queue_is_empty(struct fsnotify_group *group) 498 { 499 assert_spin_locked(&group->notification_lock); 500 501 return list_empty(&group->notification_list); 502 } 503 504 extern bool fsnotify_notify_queue_is_empty(struct fsnotify_group *group); 505 /* return, but do not dequeue the first event on the notification queue */ 506 extern struct fsnotify_event *fsnotify_peek_first_event(struct fsnotify_group *group); 507 /* return AND dequeue the first event on the notification queue */ 508 extern struct fsnotify_event *fsnotify_remove_first_event(struct fsnotify_group *group); 509 /* Remove event queued in the notification list */ 510 extern void fsnotify_remove_queued_event(struct fsnotify_group *group, 511 struct fsnotify_event *event); 512 513 /* functions used to manipulate the marks attached to inodes */ 514 515 /* Get mask of events for a list of marks */ 516 extern __u32 fsnotify_conn_mask(struct fsnotify_mark_connector *conn); 517 /* Calculate mask of events for a list of marks */ 518 extern void fsnotify_recalc_mask(struct fsnotify_mark_connector *conn); 519 extern void fsnotify_init_mark(struct fsnotify_mark *mark, 520 struct fsnotify_group *group); 521 /* Find mark belonging to given group in the list of marks */ 522 extern struct fsnotify_mark *fsnotify_find_mark(fsnotify_connp_t *connp, 523 struct fsnotify_group *group); 524 /* Get cached fsid of filesystem containing object */ 525 extern int fsnotify_get_conn_fsid(const struct fsnotify_mark_connector *conn, 526 __kernel_fsid_t *fsid); 527 /* attach the mark to the object */ 528 extern int fsnotify_add_mark(struct fsnotify_mark *mark, 529 fsnotify_connp_t *connp, unsigned int type, 530 int allow_dups, __kernel_fsid_t *fsid); 531 extern int fsnotify_add_mark_locked(struct fsnotify_mark *mark, 532 fsnotify_connp_t *connp, 533 unsigned int type, int allow_dups, 534 __kernel_fsid_t *fsid); 535 536 /* attach the mark to the inode */ 537 static inline int fsnotify_add_inode_mark(struct fsnotify_mark *mark, 538 struct inode *inode, 539 int allow_dups) 540 { 541 return fsnotify_add_mark(mark, &inode->i_fsnotify_marks, 542 FSNOTIFY_OBJ_TYPE_INODE, allow_dups, NULL); 543 } 544 static inline int fsnotify_add_inode_mark_locked(struct fsnotify_mark *mark, 545 struct inode *inode, 546 int allow_dups) 547 { 548 return fsnotify_add_mark_locked(mark, &inode->i_fsnotify_marks, 549 FSNOTIFY_OBJ_TYPE_INODE, allow_dups, 550 NULL); 551 } 552 553 /* given a group and a mark, flag mark to be freed when all references are dropped */ 554 extern void fsnotify_destroy_mark(struct fsnotify_mark *mark, 555 struct fsnotify_group *group); 556 /* detach mark from inode / mount list, group list, drop inode reference */ 557 extern void fsnotify_detach_mark(struct fsnotify_mark *mark); 558 /* free mark */ 559 extern void fsnotify_free_mark(struct fsnotify_mark *mark); 560 /* Wait until all marks queued for destruction are destroyed */ 561 extern void fsnotify_wait_marks_destroyed(void); 562 /* run all the marks in a group, and clear all of the marks attached to given object type */ 563 extern void fsnotify_clear_marks_by_group(struct fsnotify_group *group, unsigned int type); 564 /* run all the marks in a group, and clear all of the vfsmount marks */ 565 static inline void fsnotify_clear_vfsmount_marks_by_group(struct fsnotify_group *group) 566 { 567 fsnotify_clear_marks_by_group(group, FSNOTIFY_OBJ_TYPE_VFSMOUNT_FL); 568 } 569 /* run all the marks in a group, and clear all of the inode marks */ 570 static inline void fsnotify_clear_inode_marks_by_group(struct fsnotify_group *group) 571 { 572 fsnotify_clear_marks_by_group(group, FSNOTIFY_OBJ_TYPE_INODE_FL); 573 } 574 /* run all the marks in a group, and clear all of the sn marks */ 575 static inline void fsnotify_clear_sb_marks_by_group(struct fsnotify_group *group) 576 { 577 fsnotify_clear_marks_by_group(group, FSNOTIFY_OBJ_TYPE_SB_FL); 578 } 579 extern void fsnotify_get_mark(struct fsnotify_mark *mark); 580 extern void fsnotify_put_mark(struct fsnotify_mark *mark); 581 extern void fsnotify_finish_user_wait(struct fsnotify_iter_info *iter_info); 582 extern bool fsnotify_prepare_user_wait(struct fsnotify_iter_info *iter_info); 583 584 static inline void fsnotify_init_event(struct fsnotify_event *event) 585 { 586 INIT_LIST_HEAD(&event->list); 587 } 588 589 #else 590 591 static inline int fsnotify(__u32 mask, const void *data, int data_type, 592 struct inode *dir, const struct qstr *name, 593 struct inode *inode, u32 cookie) 594 { 595 return 0; 596 } 597 598 static inline int __fsnotify_parent(struct dentry *dentry, __u32 mask, 599 const void *data, int data_type) 600 { 601 return 0; 602 } 603 604 static inline void __fsnotify_inode_delete(struct inode *inode) 605 {} 606 607 static inline void __fsnotify_vfsmount_delete(struct vfsmount *mnt) 608 {} 609 610 static inline void fsnotify_sb_delete(struct super_block *sb) 611 {} 612 613 static inline void fsnotify_update_flags(struct dentry *dentry) 614 {} 615 616 static inline u32 fsnotify_get_cookie(void) 617 { 618 return 0; 619 } 620 621 static inline void fsnotify_unmount_inodes(struct super_block *sb) 622 {} 623 624 #endif /* CONFIG_FSNOTIFY */ 625 626 #endif /* __KERNEL __ */ 627 628 #endif /* __LINUX_FSNOTIFY_BACKEND_H */ 629