1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Copyright (C) 2008 Red Hat, Inc., Eric Paris <eparis@redhat.com> |
4 | */ |
5 | |
6 | #include <linux/dcache.h> |
7 | #include <linux/fs.h> |
8 | #include <linux/gfp.h> |
9 | #include <linux/init.h> |
10 | #include <linux/module.h> |
11 | #include <linux/mount.h> |
12 | #include <linux/srcu.h> |
13 | |
14 | #include <linux/fsnotify_backend.h> |
15 | #include "fsnotify.h" |
16 | |
17 | /* |
18 | * Clear all of the marks on an inode when it is being evicted from core |
19 | */ |
20 | void __fsnotify_inode_delete(struct inode *inode) |
21 | { |
22 | fsnotify_clear_marks_by_inode(inode); |
23 | } |
24 | EXPORT_SYMBOL_GPL(__fsnotify_inode_delete); |
25 | |
26 | void __fsnotify_vfsmount_delete(struct vfsmount *mnt) |
27 | { |
28 | fsnotify_clear_marks_by_mount(mnt); |
29 | } |
30 | |
31 | /** |
32 | * fsnotify_unmount_inodes - an sb is unmounting. handle any watched inodes. |
33 | * @sb: superblock being unmounted. |
34 | * |
35 | * Called during unmount with no locks held, so needs to be safe against |
36 | * concurrent modifiers. We temporarily drop sb->s_inode_list_lock and CAN block. |
37 | */ |
38 | static void fsnotify_unmount_inodes(struct super_block *sb) |
39 | { |
40 | struct inode *inode, *iput_inode = NULL; |
41 | |
42 | spin_lock(lock: &sb->s_inode_list_lock); |
43 | list_for_each_entry(inode, &sb->s_inodes, i_sb_list) { |
44 | /* |
45 | * We cannot __iget() an inode in state I_FREEING, |
46 | * I_WILL_FREE, or I_NEW which is fine because by that point |
47 | * the inode cannot have any associated watches. |
48 | */ |
49 | spin_lock(lock: &inode->i_lock); |
50 | if (inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) { |
51 | spin_unlock(lock: &inode->i_lock); |
52 | continue; |
53 | } |
54 | |
55 | /* |
56 | * If i_count is zero, the inode cannot have any watches and |
57 | * doing an __iget/iput with SB_ACTIVE clear would actually |
58 | * evict all inodes with zero i_count from icache which is |
59 | * unnecessarily violent and may in fact be illegal to do. |
60 | * However, we should have been called /after/ evict_inodes |
61 | * removed all zero refcount inodes, in any case. Test to |
62 | * be sure. |
63 | */ |
64 | if (!atomic_read(v: &inode->i_count)) { |
65 | spin_unlock(lock: &inode->i_lock); |
66 | continue; |
67 | } |
68 | |
69 | __iget(inode); |
70 | spin_unlock(lock: &inode->i_lock); |
71 | spin_unlock(lock: &sb->s_inode_list_lock); |
72 | |
73 | iput(iput_inode); |
74 | |
75 | /* for each watch, send FS_UNMOUNT and then remove it */ |
76 | fsnotify_inode(inode, FS_UNMOUNT); |
77 | |
78 | fsnotify_inode_delete(inode); |
79 | |
80 | iput_inode = inode; |
81 | |
82 | cond_resched(); |
83 | spin_lock(lock: &sb->s_inode_list_lock); |
84 | } |
85 | spin_unlock(lock: &sb->s_inode_list_lock); |
86 | |
87 | iput(iput_inode); |
88 | } |
89 | |
90 | void fsnotify_sb_delete(struct super_block *sb) |
91 | { |
92 | fsnotify_unmount_inodes(sb); |
93 | fsnotify_clear_marks_by_sb(sb); |
94 | /* Wait for outstanding object references from connectors */ |
95 | wait_var_event(&sb->s_fsnotify_connectors, |
96 | !atomic_long_read(&sb->s_fsnotify_connectors)); |
97 | } |
98 | |
99 | /* |
100 | * Given an inode, first check if we care what happens to our children. Inotify |
101 | * and dnotify both tell their parents about events. If we care about any event |
102 | * on a child we run all of our children and set a dentry flag saying that the |
103 | * parent cares. Thus when an event happens on a child it can quickly tell |
104 | * if there is a need to find a parent and send the event to the parent. |
105 | */ |
106 | void __fsnotify_update_child_dentry_flags(struct inode *inode) |
107 | { |
108 | struct dentry *alias; |
109 | int watched; |
110 | |
111 | if (!S_ISDIR(inode->i_mode)) |
112 | return; |
113 | |
114 | /* determine if the children should tell inode about their events */ |
115 | watched = fsnotify_inode_watches_children(inode); |
116 | |
117 | spin_lock(lock: &inode->i_lock); |
118 | /* run all of the dentries associated with this inode. Since this is a |
119 | * directory, there damn well better only be one item on this list */ |
120 | hlist_for_each_entry(alias, &inode->i_dentry, d_u.d_alias) { |
121 | struct dentry *child; |
122 | |
123 | /* run all of the children of the original inode and fix their |
124 | * d_flags to indicate parental interest (their parent is the |
125 | * original inode) */ |
126 | spin_lock(lock: &alias->d_lock); |
127 | list_for_each_entry(child, &alias->d_subdirs, d_child) { |
128 | if (!child->d_inode) |
129 | continue; |
130 | |
131 | spin_lock_nested(&child->d_lock, DENTRY_D_LOCK_NESTED); |
132 | if (watched) |
133 | child->d_flags |= DCACHE_FSNOTIFY_PARENT_WATCHED; |
134 | else |
135 | child->d_flags &= ~DCACHE_FSNOTIFY_PARENT_WATCHED; |
136 | spin_unlock(lock: &child->d_lock); |
137 | } |
138 | spin_unlock(lock: &alias->d_lock); |
139 | } |
140 | spin_unlock(lock: &inode->i_lock); |
141 | } |
142 | |
143 | /* Are inode/sb/mount interested in parent and name info with this event? */ |
144 | static bool fsnotify_event_needs_parent(struct inode *inode, struct mount *mnt, |
145 | __u32 mask) |
146 | { |
147 | __u32 marks_mask = 0; |
148 | |
149 | /* We only send parent/name to inode/sb/mount for events on non-dir */ |
150 | if (mask & FS_ISDIR) |
151 | return false; |
152 | |
153 | /* |
154 | * All events that are possible on child can also may be reported with |
155 | * parent/name info to inode/sb/mount. Otherwise, a watching parent |
156 | * could result in events reported with unexpected name info to sb/mount. |
157 | */ |
158 | BUILD_BUG_ON(FS_EVENTS_POSS_ON_CHILD & ~FS_EVENTS_POSS_TO_PARENT); |
159 | |
160 | /* Did either inode/sb/mount subscribe for events with parent/name? */ |
161 | marks_mask |= fsnotify_parent_needed_mask(mask: inode->i_fsnotify_mask); |
162 | marks_mask |= fsnotify_parent_needed_mask(mask: inode->i_sb->s_fsnotify_mask); |
163 | if (mnt) |
164 | marks_mask |= fsnotify_parent_needed_mask(mask: mnt->mnt_fsnotify_mask); |
165 | |
166 | /* Did they subscribe for this event with parent/name info? */ |
167 | return mask & marks_mask; |
168 | } |
169 | |
170 | /* |
171 | * Notify this dentry's parent about a child's events with child name info |
172 | * if parent is watching or if inode/sb/mount are interested in events with |
173 | * parent and name info. |
174 | * |
175 | * Notify only the child without name info if parent is not watching and |
176 | * inode/sb/mount are not interested in events with parent and name info. |
177 | */ |
178 | int __fsnotify_parent(struct dentry *dentry, __u32 mask, const void *data, |
179 | int data_type) |
180 | { |
181 | const struct path *path = fsnotify_data_path(data, data_type); |
182 | struct mount *mnt = path ? real_mount(mnt: path->mnt) : NULL; |
183 | struct inode *inode = d_inode(dentry); |
184 | struct dentry *parent; |
185 | bool parent_watched = dentry->d_flags & DCACHE_FSNOTIFY_PARENT_WATCHED; |
186 | bool parent_needed, parent_interested; |
187 | __u32 p_mask; |
188 | struct inode *p_inode = NULL; |
189 | struct name_snapshot name; |
190 | struct qstr *file_name = NULL; |
191 | int ret = 0; |
192 | |
193 | /* |
194 | * Do inode/sb/mount care about parent and name info on non-dir? |
195 | * Do they care about any event at all? |
196 | */ |
197 | if (!inode->i_fsnotify_marks && !inode->i_sb->s_fsnotify_marks && |
198 | (!mnt || !mnt->mnt_fsnotify_marks) && !parent_watched) |
199 | return 0; |
200 | |
201 | parent = NULL; |
202 | parent_needed = fsnotify_event_needs_parent(inode, mnt, mask); |
203 | if (!parent_watched && !parent_needed) |
204 | goto notify; |
205 | |
206 | /* Does parent inode care about events on children? */ |
207 | parent = dget_parent(dentry); |
208 | p_inode = parent->d_inode; |
209 | p_mask = fsnotify_inode_watches_children(inode: p_inode); |
210 | if (unlikely(parent_watched && !p_mask)) |
211 | __fsnotify_update_child_dentry_flags(inode: p_inode); |
212 | |
213 | /* |
214 | * Include parent/name in notification either if some notification |
215 | * groups require parent info or the parent is interested in this event. |
216 | */ |
217 | parent_interested = mask & p_mask & ALL_FSNOTIFY_EVENTS; |
218 | if (parent_needed || parent_interested) { |
219 | /* When notifying parent, child should be passed as data */ |
220 | WARN_ON_ONCE(inode != fsnotify_data_inode(data, data_type)); |
221 | |
222 | /* Notify both parent and child with child name info */ |
223 | take_dentry_name_snapshot(&name, dentry); |
224 | file_name = &name.name; |
225 | if (parent_interested) |
226 | mask |= FS_EVENT_ON_CHILD; |
227 | } |
228 | |
229 | notify: |
230 | ret = fsnotify(mask, data, data_type, dir: p_inode, name: file_name, inode, cookie: 0); |
231 | |
232 | if (file_name) |
233 | release_dentry_name_snapshot(&name); |
234 | dput(parent); |
235 | |
236 | return ret; |
237 | } |
238 | EXPORT_SYMBOL_GPL(__fsnotify_parent); |
239 | |
240 | static int fsnotify_handle_inode_event(struct fsnotify_group *group, |
241 | struct fsnotify_mark *inode_mark, |
242 | u32 mask, const void *data, int data_type, |
243 | struct inode *dir, const struct qstr *name, |
244 | u32 cookie) |
245 | { |
246 | const struct path *path = fsnotify_data_path(data, data_type); |
247 | struct inode *inode = fsnotify_data_inode(data, data_type); |
248 | const struct fsnotify_ops *ops = group->ops; |
249 | |
250 | if (WARN_ON_ONCE(!ops->handle_inode_event)) |
251 | return 0; |
252 | |
253 | if (WARN_ON_ONCE(!inode && !dir)) |
254 | return 0; |
255 | |
256 | if ((inode_mark->flags & FSNOTIFY_MARK_FLAG_EXCL_UNLINK) && |
257 | path && d_unlinked(dentry: path->dentry)) |
258 | return 0; |
259 | |
260 | /* Check interest of this mark in case event was sent with two marks */ |
261 | if (!(mask & inode_mark->mask & ALL_FSNOTIFY_EVENTS)) |
262 | return 0; |
263 | |
264 | return ops->handle_inode_event(inode_mark, mask, inode, dir, name, cookie); |
265 | } |
266 | |
267 | static int fsnotify_handle_event(struct fsnotify_group *group, __u32 mask, |
268 | const void *data, int data_type, |
269 | struct inode *dir, const struct qstr *name, |
270 | u32 cookie, struct fsnotify_iter_info *iter_info) |
271 | { |
272 | struct fsnotify_mark *inode_mark = fsnotify_iter_inode_mark(iter_info); |
273 | struct fsnotify_mark *parent_mark = fsnotify_iter_parent_mark(iter_info); |
274 | int ret; |
275 | |
276 | if (WARN_ON_ONCE(fsnotify_iter_sb_mark(iter_info)) || |
277 | WARN_ON_ONCE(fsnotify_iter_vfsmount_mark(iter_info))) |
278 | return 0; |
279 | |
280 | /* |
281 | * For FS_RENAME, 'dir' is old dir and 'data' is new dentry. |
282 | * The only ->handle_inode_event() backend that supports FS_RENAME is |
283 | * dnotify, where it means file was renamed within same parent. |
284 | */ |
285 | if (mask & FS_RENAME) { |
286 | struct dentry *moved = fsnotify_data_dentry(data, data_type); |
287 | |
288 | if (dir != moved->d_parent->d_inode) |
289 | return 0; |
290 | } |
291 | |
292 | if (parent_mark) { |
293 | ret = fsnotify_handle_inode_event(group, inode_mark: parent_mark, mask, |
294 | data, data_type, dir, name, cookie: 0); |
295 | if (ret) |
296 | return ret; |
297 | } |
298 | |
299 | if (!inode_mark) |
300 | return 0; |
301 | |
302 | if (mask & FS_EVENT_ON_CHILD) { |
303 | /* |
304 | * Some events can be sent on both parent dir and child marks |
305 | * (e.g. FS_ATTRIB). If both parent dir and child are |
306 | * watching, report the event once to parent dir with name (if |
307 | * interested) and once to child without name (if interested). |
308 | * The child watcher is expecting an event without a file name |
309 | * and without the FS_EVENT_ON_CHILD flag. |
310 | */ |
311 | mask &= ~FS_EVENT_ON_CHILD; |
312 | dir = NULL; |
313 | name = NULL; |
314 | } |
315 | |
316 | return fsnotify_handle_inode_event(group, inode_mark, mask, data, data_type, |
317 | dir, name, cookie); |
318 | } |
319 | |
320 | static int send_to_group(__u32 mask, const void *data, int data_type, |
321 | struct inode *dir, const struct qstr *file_name, |
322 | u32 cookie, struct fsnotify_iter_info *iter_info) |
323 | { |
324 | struct fsnotify_group *group = NULL; |
325 | __u32 test_mask = (mask & ALL_FSNOTIFY_EVENTS); |
326 | __u32 marks_mask = 0; |
327 | __u32 marks_ignore_mask = 0; |
328 | bool is_dir = mask & FS_ISDIR; |
329 | struct fsnotify_mark *mark; |
330 | int type; |
331 | |
332 | if (!iter_info->report_mask) |
333 | return 0; |
334 | |
335 | /* clear ignored on inode modification */ |
336 | if (mask & FS_MODIFY) { |
337 | fsnotify_foreach_iter_mark_type(iter_info, mark, type) { |
338 | if (!(mark->flags & |
339 | FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY)) |
340 | mark->ignore_mask = 0; |
341 | } |
342 | } |
343 | |
344 | /* Are any of the group marks interested in this event? */ |
345 | fsnotify_foreach_iter_mark_type(iter_info, mark, type) { |
346 | group = mark->group; |
347 | marks_mask |= mark->mask; |
348 | marks_ignore_mask |= |
349 | fsnotify_effective_ignore_mask(mark, is_dir, iter_type: type); |
350 | } |
351 | |
352 | pr_debug("%s: group=%p mask=%x marks_mask=%x marks_ignore_mask=%x data=%p data_type=%d dir=%p cookie=%d\n" , |
353 | __func__, group, mask, marks_mask, marks_ignore_mask, |
354 | data, data_type, dir, cookie); |
355 | |
356 | if (!(test_mask & marks_mask & ~marks_ignore_mask)) |
357 | return 0; |
358 | |
359 | if (group->ops->handle_event) { |
360 | return group->ops->handle_event(group, mask, data, data_type, dir, |
361 | file_name, cookie, iter_info); |
362 | } |
363 | |
364 | return fsnotify_handle_event(group, mask, data, data_type, dir, |
365 | name: file_name, cookie, iter_info); |
366 | } |
367 | |
368 | static struct fsnotify_mark *fsnotify_first_mark(struct fsnotify_mark_connector **connp) |
369 | { |
370 | struct fsnotify_mark_connector *conn; |
371 | struct hlist_node *node = NULL; |
372 | |
373 | conn = srcu_dereference(*connp, &fsnotify_mark_srcu); |
374 | if (conn) |
375 | node = srcu_dereference(conn->list.first, &fsnotify_mark_srcu); |
376 | |
377 | return hlist_entry_safe(node, struct fsnotify_mark, obj_list); |
378 | } |
379 | |
380 | static struct fsnotify_mark *fsnotify_next_mark(struct fsnotify_mark *mark) |
381 | { |
382 | struct hlist_node *node = NULL; |
383 | |
384 | if (mark) |
385 | node = srcu_dereference(mark->obj_list.next, |
386 | &fsnotify_mark_srcu); |
387 | |
388 | return hlist_entry_safe(node, struct fsnotify_mark, obj_list); |
389 | } |
390 | |
391 | /* |
392 | * iter_info is a multi head priority queue of marks. |
393 | * Pick a subset of marks from queue heads, all with the same group |
394 | * and set the report_mask to a subset of the selected marks. |
395 | * Returns false if there are no more groups to iterate. |
396 | */ |
397 | static bool fsnotify_iter_select_report_types( |
398 | struct fsnotify_iter_info *iter_info) |
399 | { |
400 | struct fsnotify_group *max_prio_group = NULL; |
401 | struct fsnotify_mark *mark; |
402 | int type; |
403 | |
404 | /* Choose max prio group among groups of all queue heads */ |
405 | fsnotify_foreach_iter_type(type) { |
406 | mark = iter_info->marks[type]; |
407 | if (mark && |
408 | fsnotify_compare_groups(a: max_prio_group, b: mark->group) > 0) |
409 | max_prio_group = mark->group; |
410 | } |
411 | |
412 | if (!max_prio_group) |
413 | return false; |
414 | |
415 | /* Set the report mask for marks from same group as max prio group */ |
416 | iter_info->current_group = max_prio_group; |
417 | iter_info->report_mask = 0; |
418 | fsnotify_foreach_iter_type(type) { |
419 | mark = iter_info->marks[type]; |
420 | if (mark && mark->group == iter_info->current_group) { |
421 | /* |
422 | * FSNOTIFY_ITER_TYPE_PARENT indicates that this inode |
423 | * is watching children and interested in this event, |
424 | * which is an event possible on child. |
425 | * But is *this mark* watching children? |
426 | */ |
427 | if (type == FSNOTIFY_ITER_TYPE_PARENT && |
428 | !(mark->mask & FS_EVENT_ON_CHILD) && |
429 | !(fsnotify_ignore_mask(mark) & FS_EVENT_ON_CHILD)) |
430 | continue; |
431 | |
432 | fsnotify_iter_set_report_type(iter_info, iter_type: type); |
433 | } |
434 | } |
435 | |
436 | return true; |
437 | } |
438 | |
439 | /* |
440 | * Pop from iter_info multi head queue, the marks that belong to the group of |
441 | * current iteration step. |
442 | */ |
443 | static void fsnotify_iter_next(struct fsnotify_iter_info *iter_info) |
444 | { |
445 | struct fsnotify_mark *mark; |
446 | int type; |
447 | |
448 | /* |
449 | * We cannot use fsnotify_foreach_iter_mark_type() here because we |
450 | * may need to advance a mark of type X that belongs to current_group |
451 | * but was not selected for reporting. |
452 | */ |
453 | fsnotify_foreach_iter_type(type) { |
454 | mark = iter_info->marks[type]; |
455 | if (mark && mark->group == iter_info->current_group) |
456 | iter_info->marks[type] = |
457 | fsnotify_next_mark(mark: iter_info->marks[type]); |
458 | } |
459 | } |
460 | |
461 | /* |
462 | * fsnotify - This is the main call to fsnotify. |
463 | * |
464 | * The VFS calls into hook specific functions in linux/fsnotify.h. |
465 | * Those functions then in turn call here. Here will call out to all of the |
466 | * registered fsnotify_group. Those groups can then use the notification event |
467 | * in whatever means they feel necessary. |
468 | * |
469 | * @mask: event type and flags |
470 | * @data: object that event happened on |
471 | * @data_type: type of object for fanotify_data_XXX() accessors |
472 | * @dir: optional directory associated with event - |
473 | * if @file_name is not NULL, this is the directory that |
474 | * @file_name is relative to |
475 | * @file_name: optional file name associated with event |
476 | * @inode: optional inode associated with event - |
477 | * If @dir and @inode are both non-NULL, event may be |
478 | * reported to both. |
479 | * @cookie: inotify rename cookie |
480 | */ |
481 | int fsnotify(__u32 mask, const void *data, int data_type, struct inode *dir, |
482 | const struct qstr *file_name, struct inode *inode, u32 cookie) |
483 | { |
484 | const struct path *path = fsnotify_data_path(data, data_type); |
485 | struct super_block *sb = fsnotify_data_sb(data, data_type); |
486 | struct fsnotify_iter_info iter_info = {}; |
487 | struct mount *mnt = NULL; |
488 | struct inode *inode2 = NULL; |
489 | struct dentry *moved; |
490 | int inode2_type; |
491 | int ret = 0; |
492 | __u32 test_mask, marks_mask; |
493 | |
494 | if (path) |
495 | mnt = real_mount(mnt: path->mnt); |
496 | |
497 | if (!inode) { |
498 | /* Dirent event - report on TYPE_INODE to dir */ |
499 | inode = dir; |
500 | /* For FS_RENAME, inode is old_dir and inode2 is new_dir */ |
501 | if (mask & FS_RENAME) { |
502 | moved = fsnotify_data_dentry(data, data_type); |
503 | inode2 = moved->d_parent->d_inode; |
504 | inode2_type = FSNOTIFY_ITER_TYPE_INODE2; |
505 | } |
506 | } else if (mask & FS_EVENT_ON_CHILD) { |
507 | /* |
508 | * Event on child - report on TYPE_PARENT to dir if it is |
509 | * watching children and on TYPE_INODE to child. |
510 | */ |
511 | inode2 = dir; |
512 | inode2_type = FSNOTIFY_ITER_TYPE_PARENT; |
513 | } |
514 | |
515 | /* |
516 | * Optimization: srcu_read_lock() has a memory barrier which can |
517 | * be expensive. It protects walking the *_fsnotify_marks lists. |
518 | * However, if we do not walk the lists, we do not have to do |
519 | * SRCU because we have no references to any objects and do not |
520 | * need SRCU to keep them "alive". |
521 | */ |
522 | if (!sb->s_fsnotify_marks && |
523 | (!mnt || !mnt->mnt_fsnotify_marks) && |
524 | (!inode || !inode->i_fsnotify_marks) && |
525 | (!inode2 || !inode2->i_fsnotify_marks)) |
526 | return 0; |
527 | |
528 | marks_mask = sb->s_fsnotify_mask; |
529 | if (mnt) |
530 | marks_mask |= mnt->mnt_fsnotify_mask; |
531 | if (inode) |
532 | marks_mask |= inode->i_fsnotify_mask; |
533 | if (inode2) |
534 | marks_mask |= inode2->i_fsnotify_mask; |
535 | |
536 | |
537 | /* |
538 | * If this is a modify event we may need to clear some ignore masks. |
539 | * In that case, the object with ignore masks will have the FS_MODIFY |
540 | * event in its mask. |
541 | * Otherwise, return if none of the marks care about this type of event. |
542 | */ |
543 | test_mask = (mask & ALL_FSNOTIFY_EVENTS); |
544 | if (!(test_mask & marks_mask)) |
545 | return 0; |
546 | |
547 | iter_info.srcu_idx = srcu_read_lock(ssp: &fsnotify_mark_srcu); |
548 | |
549 | iter_info.marks[FSNOTIFY_ITER_TYPE_SB] = |
550 | fsnotify_first_mark(connp: &sb->s_fsnotify_marks); |
551 | if (mnt) { |
552 | iter_info.marks[FSNOTIFY_ITER_TYPE_VFSMOUNT] = |
553 | fsnotify_first_mark(connp: &mnt->mnt_fsnotify_marks); |
554 | } |
555 | if (inode) { |
556 | iter_info.marks[FSNOTIFY_ITER_TYPE_INODE] = |
557 | fsnotify_first_mark(connp: &inode->i_fsnotify_marks); |
558 | } |
559 | if (inode2) { |
560 | iter_info.marks[inode2_type] = |
561 | fsnotify_first_mark(connp: &inode2->i_fsnotify_marks); |
562 | } |
563 | |
564 | /* |
565 | * We need to merge inode/vfsmount/sb mark lists so that e.g. inode mark |
566 | * ignore masks are properly reflected for mount/sb mark notifications. |
567 | * That's why this traversal is so complicated... |
568 | */ |
569 | while (fsnotify_iter_select_report_types(iter_info: &iter_info)) { |
570 | ret = send_to_group(mask, data, data_type, dir, file_name, |
571 | cookie, iter_info: &iter_info); |
572 | |
573 | if (ret && (mask & ALL_FSNOTIFY_PERM_EVENTS)) |
574 | goto out; |
575 | |
576 | fsnotify_iter_next(iter_info: &iter_info); |
577 | } |
578 | ret = 0; |
579 | out: |
580 | srcu_read_unlock(ssp: &fsnotify_mark_srcu, idx: iter_info.srcu_idx); |
581 | |
582 | return ret; |
583 | } |
584 | EXPORT_SYMBOL_GPL(fsnotify); |
585 | |
586 | static __init int fsnotify_init(void) |
587 | { |
588 | int ret; |
589 | |
590 | BUILD_BUG_ON(HWEIGHT32(ALL_FSNOTIFY_BITS) != 23); |
591 | |
592 | ret = init_srcu_struct(&fsnotify_mark_srcu); |
593 | if (ret) |
594 | panic(fmt: "initializing fsnotify_mark_srcu" ); |
595 | |
596 | fsnotify_mark_connector_cachep = KMEM_CACHE(fsnotify_mark_connector, |
597 | SLAB_PANIC); |
598 | |
599 | return 0; |
600 | } |
601 | core_initcall(fsnotify_init); |
602 | |