Lines Matching full:mark
7 * fsnotify inode mark locking/lifetime/and refcnting
10 * The group->recnt and mark->refcnt tell how many "things" in the kernel
13 * the reference a group and a mark hold to each other.
22 * mark->lock
23 * mark->connector->lock
26 * each mark is hooked via the g_list. It also protects the groups private
29 * mark->lock protects the marks attributes like its masks and flags.
30 * Furthermore it protects the access to a reference of the group that the mark
32 * that is being watched by the mark.
34 * mark->connector->lock protects the list of marks anchored inside an
35 * inode / vfsmount and each mark is hooked via the i_list.
39 * marks in the list and is also protected by fsnotify_mark_srcu. A mark gets
40 * detached from fsnotify_mark_connector when last reference to the mark is
41 * dropped. Thus having mark reference is enough to protect mark->connector
43 * because we remove mark from g_list before dropping mark reference associated
44 * with that, any mark found through g_list is guaranteed to have
45 * mark->connector set until we drop group->mark_mutex.
51 * The inode mark can be cleared for a number of different reasons including:
56 * - The fsnotify_group associated with the mark is going away and all such marks
94 void fsnotify_get_mark(struct fsnotify_mark *mark) in fsnotify_get_mark() argument
96 WARN_ON_ONCE(!refcount_read(&mark->refcnt)); in fsnotify_get_mark()
97 refcount_inc(&mark->refcnt); in fsnotify_get_mark()
130 * iput() outside of spinlocks. This happens when last mark that wanted iref is
144 /* Pin inode if any mark wants inode refcount held */ in fsnotify_update_iref()
148 /* Unpin inode after detach of last mark that wanted iref */ in fsnotify_update_iref()
160 struct fsnotify_mark *mark; in __fsnotify_recalc_mask() local
166 hlist_for_each_entry(mark, &conn->list, obj_list) { in __fsnotify_recalc_mask()
167 if (!(mark->flags & FSNOTIFY_MARK_FLAG_ATTACHED)) in __fsnotify_recalc_mask()
169 new_mask |= fsnotify_calc_mask(mark); in __fsnotify_recalc_mask()
171 !(mark->flags & FSNOTIFY_MARK_FLAG_NO_IREF)) in __fsnotify_recalc_mask()
200 * this by holding a mark->lock or mark->group->mark_mutex for a mark on this
298 static void fsnotify_final_mark_destroy(struct fsnotify_mark *mark) in fsnotify_final_mark_destroy() argument
300 struct fsnotify_group *group = mark->group; in fsnotify_final_mark_destroy()
304 group->ops->free_mark(mark); in fsnotify_final_mark_destroy()
319 void fsnotify_put_mark(struct fsnotify_mark *mark) in fsnotify_put_mark() argument
321 struct fsnotify_mark_connector *conn = READ_ONCE(mark->connector); in fsnotify_put_mark()
328 if (refcount_dec_and_test(&mark->refcnt)) in fsnotify_put_mark()
329 fsnotify_final_mark_destroy(mark); in fsnotify_put_mark()
335 * safely grab mark reference. in fsnotify_put_mark()
337 if (!refcount_dec_and_lock(&mark->refcnt, &conn->lock)) in fsnotify_put_mark()
340 hlist_del_init_rcu(&mark->obj_list); in fsnotify_put_mark()
348 WRITE_ONCE(mark->connector, NULL); in fsnotify_put_mark()
367 list_add(&mark->g_list, &destroy_list); in fsnotify_put_mark()
375 * Get mark reference when we found the mark via lockless traversal of object
376 * list. Mark can be already removed from the list by now and on its way to be
381 static bool fsnotify_get_mark_safe(struct fsnotify_mark *mark) in fsnotify_get_mark_safe() argument
383 if (!mark) in fsnotify_get_mark_safe()
386 if (refcount_inc_not_zero(&mark->refcnt)) { in fsnotify_get_mark_safe()
387 spin_lock(&mark->lock); in fsnotify_get_mark_safe()
388 if (mark->flags & FSNOTIFY_MARK_FLAG_ATTACHED) { in fsnotify_get_mark_safe()
389 /* mark is attached, group is still alive then */ in fsnotify_get_mark_safe()
390 atomic_inc(&mark->group->user_waits); in fsnotify_get_mark_safe()
391 spin_unlock(&mark->lock); in fsnotify_get_mark_safe()
394 spin_unlock(&mark->lock); in fsnotify_get_mark_safe()
395 fsnotify_put_mark(mark); in fsnotify_get_mark_safe()
405 static void fsnotify_put_mark_wake(struct fsnotify_mark *mark) in fsnotify_put_mark_wake() argument
407 if (mark) { in fsnotify_put_mark_wake()
408 struct fsnotify_group *group = mark->group; in fsnotify_put_mark_wake()
410 fsnotify_put_mark(mark); in fsnotify_put_mark_wake()
426 /* This can fail if mark is being removed */ in fsnotify_prepare_user_wait()
459 * Mark mark as detached, remove it from group list. Mark still stays in object
460 * list until its last reference is dropped. Note that we rely on mark being
462 * particular we rely on mark->connector being valid while we hold
463 * group->mark_mutex if we found the mark through g_list.
466 * reference to the mark or be protected by fsnotify_mark_srcu.
468 void fsnotify_detach_mark(struct fsnotify_mark *mark) in fsnotify_detach_mark() argument
470 fsnotify_group_assert_locked(mark->group); in fsnotify_detach_mark()
472 refcount_read(&mark->refcnt) < 1 + in fsnotify_detach_mark()
473 !!(mark->flags & FSNOTIFY_MARK_FLAG_ATTACHED)); in fsnotify_detach_mark()
475 spin_lock(&mark->lock); in fsnotify_detach_mark()
476 /* something else already called this function on this mark */ in fsnotify_detach_mark()
477 if (!(mark->flags & FSNOTIFY_MARK_FLAG_ATTACHED)) { in fsnotify_detach_mark()
478 spin_unlock(&mark->lock); in fsnotify_detach_mark()
481 mark->flags &= ~FSNOTIFY_MARK_FLAG_ATTACHED; in fsnotify_detach_mark()
482 list_del_init(&mark->g_list); in fsnotify_detach_mark()
483 spin_unlock(&mark->lock); in fsnotify_detach_mark()
485 /* Drop mark reference acquired in fsnotify_add_mark_locked() */ in fsnotify_detach_mark()
486 fsnotify_put_mark(mark); in fsnotify_detach_mark()
490 * Free fsnotify mark. The mark is actually only marked as being freed. The
491 * freeing is actually happening only once last reference to the mark is
494 * Caller must have a reference to the mark or be protected by
497 void fsnotify_free_mark(struct fsnotify_mark *mark) in fsnotify_free_mark() argument
499 struct fsnotify_group *group = mark->group; in fsnotify_free_mark()
501 spin_lock(&mark->lock); in fsnotify_free_mark()
502 /* something else already called this function on this mark */ in fsnotify_free_mark()
503 if (!(mark->flags & FSNOTIFY_MARK_FLAG_ALIVE)) { in fsnotify_free_mark()
504 spin_unlock(&mark->lock); in fsnotify_free_mark()
507 mark->flags &= ~FSNOTIFY_MARK_FLAG_ALIVE; in fsnotify_free_mark()
508 spin_unlock(&mark->lock); in fsnotify_free_mark()
512 * callback to the group function to let it know that this mark in fsnotify_free_mark()
516 group->ops->freeing_mark(mark, group); in fsnotify_free_mark()
519 void fsnotify_destroy_mark(struct fsnotify_mark *mark, in fsnotify_destroy_mark() argument
523 fsnotify_detach_mark(mark); in fsnotify_destroy_mark()
525 fsnotify_free_mark(mark); in fsnotify_destroy_mark()
603 * Get mark connector, make sure it is alive and return with its lock held.
605 * hold reference to a mark on the list may directly lock connector->lock as
630 * Add mark into proper place in given list of marks. These marks may be used
635 static int fsnotify_add_mark_list(struct fsnotify_mark *mark, in fsnotify_add_mark_list() argument
653 spin_lock(&mark->lock); in fsnotify_add_mark_list()
656 spin_unlock(&mark->lock); in fsnotify_add_mark_list()
685 /* is mark the first mark? */ in fsnotify_add_mark_list()
687 hlist_add_head_rcu(&mark->obj_list, &conn->list); in fsnotify_add_mark_list()
691 /* should mark be in the middle of the current list? */ in fsnotify_add_mark_list()
695 if ((lmark->group == mark->group) && in fsnotify_add_mark_list()
697 !(mark->group->flags & FSNOTIFY_GROUP_DUPS)) { in fsnotify_add_mark_list()
702 cmp = fsnotify_compare_groups(lmark->group, mark->group); in fsnotify_add_mark_list()
704 hlist_add_before_rcu(&mark->obj_list, &lmark->obj_list); in fsnotify_add_mark_list()
710 /* mark should be the last entry. last is the current last entry */ in fsnotify_add_mark_list()
711 hlist_add_behind_rcu(&mark->obj_list, &last->obj_list); in fsnotify_add_mark_list()
716 * seeing mark->connector set. in fsnotify_add_mark_list()
718 WRITE_ONCE(mark->connector, conn); in fsnotify_add_mark_list()
721 spin_unlock(&mark->lock); in fsnotify_add_mark_list()
726 * Attach an initialized mark to a given group and fs object.
730 int fsnotify_add_mark_locked(struct fsnotify_mark *mark, in fsnotify_add_mark_locked() argument
734 struct fsnotify_group *group = mark->group; in fsnotify_add_mark_locked()
742 * mark->lock in fsnotify_add_mark_locked()
743 * mark->connector->lock in fsnotify_add_mark_locked()
745 spin_lock(&mark->lock); in fsnotify_add_mark_locked()
746 mark->flags |= FSNOTIFY_MARK_FLAG_ALIVE | FSNOTIFY_MARK_FLAG_ATTACHED; in fsnotify_add_mark_locked()
748 list_add(&mark->g_list, &group->marks_list); in fsnotify_add_mark_locked()
749 fsnotify_get_mark(mark); /* for g_list */ in fsnotify_add_mark_locked()
750 spin_unlock(&mark->lock); in fsnotify_add_mark_locked()
752 ret = fsnotify_add_mark_list(mark, connp, obj_type, add_flags, fsid); in fsnotify_add_mark_locked()
756 fsnotify_recalc_mask(mark->connector); in fsnotify_add_mark_locked()
760 spin_lock(&mark->lock); in fsnotify_add_mark_locked()
761 mark->flags &= ~(FSNOTIFY_MARK_FLAG_ALIVE | in fsnotify_add_mark_locked()
763 list_del_init(&mark->g_list); in fsnotify_add_mark_locked()
764 spin_unlock(&mark->lock); in fsnotify_add_mark_locked()
766 fsnotify_put_mark(mark); in fsnotify_add_mark_locked()
770 int fsnotify_add_mark(struct fsnotify_mark *mark, fsnotify_connp_t *connp, in fsnotify_add_mark() argument
775 struct fsnotify_group *group = mark->group; in fsnotify_add_mark()
778 ret = fsnotify_add_mark_locked(mark, connp, obj_type, add_flags, fsid); in fsnotify_add_mark()
785 * Given a list of marks, find the mark associated with given group. If found
786 * take a reference to that mark and return it, else return NULL.
792 struct fsnotify_mark *mark; in fsnotify_find_mark() local
798 hlist_for_each_entry(mark, &conn->list, obj_list) { in fsnotify_find_mark()
799 if (mark->group == group && in fsnotify_find_mark()
800 (mark->flags & FSNOTIFY_MARK_FLAG_ATTACHED)) { in fsnotify_find_mark()
801 fsnotify_get_mark(mark); in fsnotify_find_mark()
803 return mark; in fsnotify_find_mark()
815 struct fsnotify_mark *lmark, *mark; in fsnotify_clear_marks_by_group() local
828 * list. And freeing mark requires us to drop mark_mutex. So we can in fsnotify_clear_marks_by_group()
829 * reliably free only the first mark in the list. That's why we first in fsnotify_clear_marks_by_group()
834 list_for_each_entry_safe(mark, lmark, &group->marks_list, g_list) { in fsnotify_clear_marks_by_group()
835 if (mark->connector->type == obj_type) in fsnotify_clear_marks_by_group()
836 list_move(&mark->g_list, &to_free); in fsnotify_clear_marks_by_group()
847 mark = list_first_entry(head, struct fsnotify_mark, g_list); in fsnotify_clear_marks_by_group()
848 fsnotify_get_mark(mark); in fsnotify_clear_marks_by_group()
849 fsnotify_detach_mark(mark); in fsnotify_clear_marks_by_group()
851 fsnotify_free_mark(mark); in fsnotify_clear_marks_by_group()
852 fsnotify_put_mark(mark); in fsnotify_clear_marks_by_group()
860 struct fsnotify_mark *mark, *old_mark = NULL; in fsnotify_destroy_marks() local
870 * list can get modified. However we are holding mark reference and in fsnotify_destroy_marks()
871 * thus our mark cannot be removed from obj_list so we can continue in fsnotify_destroy_marks()
874 hlist_for_each_entry(mark, &conn->list, obj_list) { in fsnotify_destroy_marks()
875 fsnotify_get_mark(mark); in fsnotify_destroy_marks()
879 old_mark = mark; in fsnotify_destroy_marks()
880 fsnotify_destroy_mark(mark, mark->group); in fsnotify_destroy_marks()
885 * mark references get dropped. It would lead to strange results such in fsnotify_destroy_marks()
898 void fsnotify_init_mark(struct fsnotify_mark *mark, in fsnotify_init_mark() argument
901 memset(mark, 0, sizeof(*mark)); in fsnotify_init_mark()
902 spin_lock_init(&mark->lock); in fsnotify_init_mark()
903 refcount_set(&mark->refcnt, 1); in fsnotify_init_mark()
905 mark->group = group; in fsnotify_init_mark()
906 WRITE_ONCE(mark->connector, NULL); in fsnotify_init_mark()
916 struct fsnotify_mark *mark, *next; in fsnotify_mark_destroy_workfn() local
926 list_for_each_entry_safe(mark, next, &private_destroy_list, g_list) { in fsnotify_mark_destroy_workfn()
927 list_del_init(&mark->g_list); in fsnotify_mark_destroy_workfn()
928 fsnotify_final_mark_destroy(mark); in fsnotify_mark_destroy_workfn()