diff options
Diffstat (limited to 'fs/notify/fanotify/fanotify.c')
| -rw-r--r-- | fs/notify/fanotify/fanotify.c | 40 |
1 files changed, 33 insertions, 7 deletions
diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c index 43a606f15370..50b3abc06215 100644 --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -149,12 +149,15 @@ static bool fanotify_should_merge(struct fanotify_event *old, } /* and the list better be locked by something too! */ -static int fanotify_merge(struct list_head *list, struct fsnotify_event *event) +static int fanotify_merge(struct fsnotify_group *group, + struct fsnotify_event *event) { - struct fsnotify_event *test_event; struct fanotify_event *old, *new = FANOTIFY_E(event); + unsigned int bucket = fanotify_event_hash_bucket(group, new); + struct hlist_head *hlist = &group->fanotify_data.merge_hash[bucket]; - pr_debug("%s: list=%p event=%p\n", __func__, list, event); + pr_debug("%s: group=%p event=%p bucket=%u\n", __func__, + group, event, bucket); /* * Don't merge a permission event with any other event so that we know @@ -164,8 +167,7 @@ static int fanotify_merge(struct list_head *list, struct fsnotify_event *event) if (fanotify_is_perm_event(new->mask)) return 0; - list_for_each_entry_reverse(test_event, list, list) { - old = FANOTIFY_E(test_event); + hlist_for_each_entry(old, hlist, merge_list) { if (fanotify_should_merge(old, new)) { old->mask |= new->mask; return 1; @@ -203,8 +205,11 @@ static int fanotify_get_response(struct fsnotify_group *group, return ret; } /* Event not yet reported? Just remove it. */ - if (event->state == FAN_EVENT_INIT) + if (event->state == FAN_EVENT_INIT) { fsnotify_remove_queued_event(group, &event->fae.fse); + /* Permission events are not supposed to be hashed */ + WARN_ON_ONCE(!hlist_unhashed(&event->fae.merge_list)); + } /* * Event may be also answered in case signal delivery raced * with wakeup. In that case we have nothing to do besides @@ -679,6 +684,24 @@ static __kernel_fsid_t fanotify_get_fsid(struct fsnotify_iter_info *iter_info) return fsid; } +/* + * Add an event to hash table for faster merge. + */ +static void fanotify_insert_event(struct fsnotify_group *group, + struct fsnotify_event *fsn_event) +{ + struct fanotify_event *event = FANOTIFY_E(fsn_event); + unsigned int bucket = fanotify_event_hash_bucket(group, event); + struct hlist_head *hlist = &group->fanotify_data.merge_hash[bucket]; + + assert_spin_locked(&group->notification_lock); + + pr_debug("%s: group=%p event=%p bucket=%u\n", __func__, + group, event, bucket); + + hlist_add_head(&event->merge_list, hlist); +} + static int fanotify_handle_event(struct fsnotify_group *group, u32 mask, const void *data, int data_type, struct inode *dir, @@ -749,7 +772,9 @@ static int fanotify_handle_event(struct fsnotify_group *group, u32 mask, } fsn_event = &event->fse; - ret = fsnotify_add_event(group, fsn_event, fanotify_merge); + ret = fsnotify_add_event(group, fsn_event, fanotify_merge, + fanotify_is_hashed_event(mask) ? + fanotify_insert_event : NULL); if (ret) { /* Permission events shouldn't be merged */ BUG_ON(ret == 1 && mask & FANOTIFY_PERM_EVENTS); @@ -772,6 +797,7 @@ static void fanotify_free_group_priv(struct fsnotify_group *group) { struct user_struct *user; + kfree(group->fanotify_data.merge_hash); user = group->fanotify_data.user; atomic_dec(&user->fanotify_listeners); free_uid(user); |