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-rw-r--r--fs/notify/inotify/inotify_fsnotify.c56
-rw-r--r--fs/notify/inotify/inotify_user.c2
-rw-r--r--fs/notify/notification.c73
-rw-r--r--include/linux/fsnotify_backend.h6
4 files changed, 79 insertions, 58 deletions
diff --git a/fs/notify/inotify/inotify_fsnotify.c b/fs/notify/inotify/inotify_fsnotify.c
index 1f33234cc308..0a0f5d0f0d0a 100644
--- a/fs/notify/inotify/inotify_fsnotify.c
+++ b/fs/notify/inotify/inotify_fsnotify.c
@@ -32,6 +32,60 @@
#include "inotify.h"
+/*
+ * Check if 2 events contain the same information. We do not compare private data
+ * but at this moment that isn't a problem for any know fsnotify listeners.
+ */
+static bool event_compare(struct fsnotify_event *old, struct fsnotify_event *new)
+{
+ if ((old->mask == new->mask) &&
+ (old->to_tell == new->to_tell) &&
+ (old->data_type == new->data_type) &&
+ (old->name_len == new->name_len)) {
+ switch (old->data_type) {
+ case (FSNOTIFY_EVENT_INODE):
+ /* remember, after old was put on the wait_q we aren't
+ * allowed to look at the inode any more, only thing
+ * left to check was if the file_name is the same */
+ if (!old->name_len ||
+ !strcmp(old->file_name, new->file_name))
+ return true;
+ break;
+ case (FSNOTIFY_EVENT_PATH):
+ if ((old->path.mnt == new->path.mnt) &&
+ (old->path.dentry == new->path.dentry))
+ return true;
+ break;
+ case (FSNOTIFY_EVENT_NONE):
+ if (old->mask & FS_Q_OVERFLOW)
+ return true;
+ else if (old->mask & FS_IN_IGNORED)
+ return false;
+ return true;
+ };
+ }
+ return false;
+}
+
+static int inotify_merge(struct list_head *list, struct fsnotify_event *event)
+{
+ struct fsnotify_event_holder *last_holder;
+ struct fsnotify_event *last_event;
+ int ret = 0;
+
+ /* and the list better be locked by something too */
+ spin_lock(&event->lock);
+
+ last_holder = list_entry(list->prev, struct fsnotify_event_holder, event_list);
+ last_event = last_holder->event;
+ if (event_compare(last_event, event))
+ ret = -EEXIST;
+
+ spin_unlock(&event->lock);
+
+ return ret;
+}
+
static int inotify_handle_event(struct fsnotify_group *group, struct fsnotify_event *event)
{
struct fsnotify_mark_entry *entry;
@@ -62,7 +116,7 @@ static int inotify_handle_event(struct fsnotify_group *group, struct fsnotify_ev
fsn_event_priv->group = group;
event_priv->wd = wd;
- ret = fsnotify_add_notify_event(group, event, fsn_event_priv);
+ ret = fsnotify_add_notify_event(group, event, fsn_event_priv, inotify_merge);
if (ret) {
inotify_free_event_priv(fsn_event_priv);
/* EEXIST says we tail matched, EOVERFLOW isn't something
diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
index f2b542479e91..cbe16df326f8 100644
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -531,7 +531,7 @@ void inotify_ignored_and_remove_idr(struct fsnotify_mark_entry *entry,
fsn_event_priv->group = group;
event_priv->wd = ientry->wd;
- ret = fsnotify_add_notify_event(group, ignored_event, fsn_event_priv);
+ ret = fsnotify_add_notify_event(group, ignored_event, fsn_event_priv, NULL);
if (ret)
inotify_free_event_priv(fsn_event_priv);
diff --git a/fs/notify/notification.c b/fs/notify/notification.c
index b34ce7ad0409..6dc96b35e4a7 100644
--- a/fs/notify/notification.c
+++ b/fs/notify/notification.c
@@ -104,7 +104,8 @@ struct fsnotify_event_holder *fsnotify_alloc_event_holder(void)
void fsnotify_destroy_event_holder(struct fsnotify_event_holder *holder)
{
- kmem_cache_free(fsnotify_event_holder_cachep, holder);
+ if (holder)
+ kmem_cache_free(fsnotify_event_holder_cachep, holder);
}
/*
@@ -129,53 +130,17 @@ struct fsnotify_event_private_data *fsnotify_remove_priv_from_event(struct fsnot
}
/*
- * Check if 2 events contain the same information. We do not compare private data
- * but at this moment that isn't a problem for any know fsnotify listeners.
- */
-static bool event_compare(struct fsnotify_event *old, struct fsnotify_event *new)
-{
- if ((old->mask == new->mask) &&
- (old->to_tell == new->to_tell) &&
- (old->data_type == new->data_type) &&
- (old->name_len == new->name_len)) {
- switch (old->data_type) {
- case (FSNOTIFY_EVENT_INODE):
- /* remember, after old was put on the wait_q we aren't
- * allowed to look at the inode any more, only thing
- * left to check was if the file_name is the same */
- if (!old->name_len ||
- !strcmp(old->file_name, new->file_name))
- return true;
- break;
- case (FSNOTIFY_EVENT_PATH):
- if ((old->path.mnt == new->path.mnt) &&
- (old->path.dentry == new->path.dentry))
- return true;
- break;
- case (FSNOTIFY_EVENT_NONE):
- if (old->mask & FS_Q_OVERFLOW)
- return true;
- else if (old->mask & FS_IN_IGNORED)
- return false;
- return false;
- };
- }
- return false;
-}
-
-/*
* Add an event to the group notification queue. The group can later pull this
* event off the queue to deal with. If the event is successfully added to the
* group's notification queue, a reference is taken on event.
*/
int fsnotify_add_notify_event(struct fsnotify_group *group, struct fsnotify_event *event,
- struct fsnotify_event_private_data *priv)
+ struct fsnotify_event_private_data *priv,
+ int (*merge)(struct list_head *, struct fsnotify_event *))
{
struct fsnotify_event_holder *holder = NULL;
struct list_head *list = &group->notification_list;
- struct fsnotify_event_holder *last_holder;
- struct fsnotify_event *last_event;
- int ret = 0;
+ int rc = 0;
/*
* There is one fsnotify_event_holder embedded inside each fsnotify_event.
@@ -196,11 +161,23 @@ alloc_holder:
if (group->q_len >= group->max_events) {
event = q_overflow_event;
- ret = -EOVERFLOW;
+ rc = -EOVERFLOW;
/* sorry, no private data on the overflow event */
priv = NULL;
}
+ if (!list_empty(list) && merge) {
+ int ret;
+
+ ret = merge(list, event);
+ if (ret) {
+ mutex_unlock(&group->notification_mutex);
+ if (holder != &event->holder)
+ fsnotify_destroy_event_holder(holder);
+ return ret;
+ }
+ }
+
spin_lock(&event->lock);
if (list_empty(&event->holder.event_list)) {
@@ -215,18 +192,6 @@ alloc_holder:
goto alloc_holder;
}
- if (!list_empty(list)) {
- last_holder = list_entry(list->prev, struct fsnotify_event_holder, event_list);
- last_event = last_holder->event;
- if (event_compare(last_event, event)) {
- spin_unlock(&event->lock);
- mutex_unlock(&group->notification_mutex);
- if (holder != &event->holder)
- fsnotify_destroy_event_holder(holder);
- return -EEXIST;
- }
- }
-
group->q_len++;
holder->event = event;
@@ -238,7 +203,7 @@ alloc_holder:
mutex_unlock(&group->notification_mutex);
wake_up(&group->notification_waitq);
- return ret;
+ return rc;
}
/*
diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h
index 0e0c2b76b067..25789d45fad8 100644
--- a/include/linux/fsnotify_backend.h
+++ b/include/linux/fsnotify_backend.h
@@ -328,8 +328,10 @@ extern struct fsnotify_event_private_data *fsnotify_remove_priv_from_event(struc
struct fsnotify_event *event);
/* attach the event to the group notification queue */
-extern int fsnotify_add_notify_event(struct fsnotify_group *group, struct fsnotify_event *event,
- struct fsnotify_event_private_data *priv);
+extern int fsnotify_add_notify_event(struct fsnotify_group *group,
+ struct fsnotify_event *event,
+ struct fsnotify_event_private_data *priv,
+ int (*merge)(struct list_head *, struct fsnotify_event *));
/* true if the group notification queue is empty */
extern bool fsnotify_notify_queue_is_empty(struct fsnotify_group *group);
/* return, but do not dequeue the first event on the notification queue */
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