diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c index 3ffb9dbcab08..c35c1175c4cf 100644 --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -6,6 +6,45 @@ #include "fanotify.h" +static bool should_merge(struct fsnotify_event *old, struct fsnotify_event *new) +{ + pr_debug("%s: old=%p new=%p\n", __func__, old, new); + + if ((old->mask == new->mask) && + (old->to_tell == new->to_tell) && + (old->data_type == new->data_type)) { + switch (old->data_type) { + case (FSNOTIFY_EVENT_PATH): + if ((old->path.mnt == new->path.mnt) && + (old->path.dentry == new->path.dentry)) + return true; + case (FSNOTIFY_EVENT_NONE): + return true; + default: + BUG(); + }; + } + return false; +} + +static int fanotify_merge(struct list_head *list, struct fsnotify_event *event) +{ + struct fsnotify_event_holder *holder; + struct fsnotify_event *test_event; + + pr_debug("%s: list=%p event=%p\n", __func__, list, event); + + /* and the list better be locked by something too! */ + + list_for_each_entry_reverse(holder, list, event_list) { + test_event = holder->event; + if (should_merge(test_event, event)) + return -EEXIST; + } + + return 0; +} + static int fanotify_handle_event(struct fsnotify_group *group, struct fsnotify_event *event) { int ret; @@ -21,8 +60,10 @@ static int fanotify_handle_event(struct fsnotify_group *group, struct fsnotify_e pr_debug("%s: group=%p event=%p\n", __func__, group, event); - ret = fsnotify_add_notify_event(group, event, NULL, NULL); - + ret = fsnotify_add_notify_event(group, event, NULL, fanotify_merge); + /* -EEXIST means this event was merged with another, not that it was an error */ + if (ret == -EEXIST) + ret = 0; return ret; }