diff options
| -rw-r--r-- | fs/notify/fanotify/fanotify.c | 103 | ||||
| -rw-r--r-- | fs/notify/inotify/inotify_fsnotify.c | 28 | ||||
| -rw-r--r-- | fs/notify/inotify/inotify_user.c | 11 | ||||
| -rw-r--r-- | fs/notify/notification.c | 42 | ||||
| -rw-r--r-- | include/linux/fsnotify_backend.h | 12 |
5 files changed, 101 insertions, 95 deletions
diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c index bbcfccd4a8ea..f3c40c0e2b86 100644 --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -30,65 +30,58 @@ static bool should_merge(struct fsnotify_event *old, struct fsnotify_event *new) return false; } -/* Note, if we return an event in *arg that a reference is being held... */ -static int fanotify_merge(struct list_head *list, - struct fsnotify_event *event, - void **arg) +/* and the list better be locked by something too! */ +static struct fsnotify_event *fanotify_merge(struct list_head *list, + struct fsnotify_event *event) { struct fsnotify_event_holder *test_holder; - struct fsnotify_event *test_event; + struct fsnotify_event *test_event = NULL; struct fsnotify_event *new_event; - struct fsnotify_event **return_event = (struct fsnotify_event **)arg; - int ret = 0; pr_debug("%s: list=%p event=%p\n", __func__, list, event); - *return_event = NULL; - - /* and the list better be locked by something too! */ list_for_each_entry_reverse(test_holder, list, event_list) { - test_event = test_holder->event; - if (should_merge(test_event, event)) { - fsnotify_get_event(test_event); - *return_event = test_event; - - ret = -EEXIST; - /* if they are exactly the same we are done */ - if (test_event->mask == event->mask) - goto out; - - /* - * if the refcnt == 1 this is the only queue - * for this event and so we can update the mask - * in place. - */ - if (atomic_read(&test_event->refcnt) == 1) { - test_event->mask |= event->mask; - goto out; - } - - /* can't allocate memory, merge was no possible */ - new_event = fsnotify_clone_event(test_event); - if (unlikely(!new_event)) { - ret = 0; - goto out; - } - - /* we didn't return the test_event, so drop that ref */ - fsnotify_put_event(test_event); - /* the reference we return on new_event is from clone */ - *return_event = new_event; - - /* build new event and replace it on the list */ - new_event->mask = (test_event->mask | event->mask); - fsnotify_replace_event(test_holder, new_event); - + if (should_merge(test_holder->event, event)) { + test_event = test_holder->event; break; } } -out: - return ret; + + if (!test_event) + return NULL; + + fsnotify_get_event(test_event); + + /* if they are exactly the same we are done */ + if (test_event->mask == event->mask) + return test_event; + + /* + * if the refcnt == 2 this is the only queue + * for this event and so we can update the mask + * in place. + */ + if (atomic_read(&test_event->refcnt) == 2) { + test_event->mask |= event->mask; + return test_event; + } + + new_event = fsnotify_clone_event(test_event); + + /* done with test_event */ + fsnotify_put_event(test_event); + + /* couldn't allocate memory, merge was not possible */ + if (unlikely(!new_event)) + return ERR_PTR(-ENOMEM); + + /* build new event and replace it on the list */ + new_event->mask = (test_event->mask | event->mask); + fsnotify_replace_event(test_holder, new_event); + + /* we hold a reference on new_event from clone_event */ + return new_event; } #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS @@ -123,7 +116,7 @@ static int fanotify_get_response_from_access(struct fsnotify_group *group, static int fanotify_handle_event(struct fsnotify_group *group, struct fsnotify_event *event) { - int ret; + int ret = 0; struct fsnotify_event *notify_event = NULL; BUILD_BUG_ON(FAN_ACCESS != FS_ACCESS); @@ -138,13 +131,9 @@ 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, fanotify_merge, - (void **)¬ify_event); - /* -EEXIST means this event was merged with another, not that it was an error */ - if (ret == -EEXIST) - ret = 0; - if (ret) - goto out; + notify_event = fsnotify_add_notify_event(group, event, NULL, fanotify_merge); + if (IS_ERR(notify_event)) + return PTR_ERR(notify_event); #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS if (event->mask & FAN_ALL_PERM_EVENTS) { @@ -155,9 +144,9 @@ static int fanotify_handle_event(struct fsnotify_group *group, struct fsnotify_e } #endif -out: if (notify_event) fsnotify_put_event(notify_event); + return ret; } diff --git a/fs/notify/inotify/inotify_fsnotify.c b/fs/notify/inotify/inotify_fsnotify.c index 906b72761b17..73a1106b3542 100644 --- a/fs/notify/inotify/inotify_fsnotify.c +++ b/fs/notify/inotify/inotify_fsnotify.c @@ -68,13 +68,11 @@ static bool event_compare(struct fsnotify_event *old, struct fsnotify_event *new return false; } -static int inotify_merge(struct list_head *list, - struct fsnotify_event *event, - void **arg) +static struct fsnotify_event *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); @@ -82,11 +80,13 @@ static int inotify_merge(struct list_head *list, 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; + fsnotify_get_event(last_event); + else + last_event = NULL; spin_unlock(&event->lock); - return ret; + return last_event; } static int inotify_handle_event(struct fsnotify_group *group, struct fsnotify_event *event) @@ -96,7 +96,8 @@ static int inotify_handle_event(struct fsnotify_group *group, struct fsnotify_ev struct inode *to_tell; struct inotify_event_private_data *event_priv; struct fsnotify_event_private_data *fsn_event_priv; - int wd, ret; + struct fsnotify_event *added_event; + int wd, ret = 0; pr_debug("%s: group=%p event=%p to_tell=%p mask=%x\n", __func__, group, event, event->to_tell, event->mask); @@ -120,14 +121,13 @@ 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, inotify_merge, NULL); - if (ret) { + added_event = fsnotify_add_notify_event(group, event, fsn_event_priv, inotify_merge); + if (added_event) { inotify_free_event_priv(fsn_event_priv); - /* EEXIST says we tail matched, EOVERFLOW isn't something - * to report up the stack. */ - if ((ret == -EEXIST) || - (ret == -EOVERFLOW)) - ret = 0; + if (!IS_ERR(added_event)) + fsnotify_put_event(added_event); + else + ret = PTR_ERR(added_event); } if (fsn_mark->mask & IN_ONESHOT) diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c index 1068e1ca9cb0..a4cd227c4c76 100644 --- a/fs/notify/inotify/inotify_user.c +++ b/fs/notify/inotify/inotify_user.c @@ -516,7 +516,7 @@ void inotify_ignored_and_remove_idr(struct fsnotify_mark *fsn_mark, struct fsnotify_group *group) { struct inotify_inode_mark *i_mark; - struct fsnotify_event *ignored_event; + struct fsnotify_event *ignored_event, *notify_event; struct inotify_event_private_data *event_priv; struct fsnotify_event_private_data *fsn_event_priv; int ret; @@ -538,9 +538,14 @@ void inotify_ignored_and_remove_idr(struct fsnotify_mark *fsn_mark, fsn_event_priv->group = group; event_priv->wd = i_mark->wd; - ret = fsnotify_add_notify_event(group, ignored_event, fsn_event_priv, NULL, NULL); - if (ret) + notify_event = fsnotify_add_notify_event(group, ignored_event, fsn_event_priv, NULL); + if (notify_event) { + if (IS_ERR(notify_event)) + ret = PTR_ERR(notify_event); + else + fsnotify_put_event(notify_event); inotify_free_event_priv(fsn_event_priv); + } skip_send_ignore: diff --git a/fs/notify/notification.c b/fs/notify/notification.c index e6dde25fb99b..f39260f8f865 100644 --- a/fs/notify/notification.c +++ b/fs/notify/notification.c @@ -137,16 +137,14 @@ struct fsnotify_event_private_data *fsnotify_remove_priv_from_event(struct fsnot * 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, - int (*merge)(struct list_head *, - struct fsnotify_event *, - void **arg), - void **arg) +struct fsnotify_event *fsnotify_add_notify_event(struct fsnotify_group *group, struct fsnotify_event *event, + struct fsnotify_event_private_data *priv, + struct fsnotify_event *(*merge)(struct list_head *, + struct fsnotify_event *)) { + struct fsnotify_event *return_event = NULL; struct fsnotify_event_holder *holder = NULL; struct list_head *list = &group->notification_list; - int rc = 0; pr_debug("%s: group=%p event=%p priv=%p\n", __func__, group, event, priv); @@ -162,27 +160,37 @@ int fsnotify_add_notify_event(struct fsnotify_group *group, struct fsnotify_even alloc_holder: holder = fsnotify_alloc_event_holder(); if (!holder) - return -ENOMEM; + return ERR_PTR(-ENOMEM); } mutex_lock(&group->notification_mutex); if (group->q_len >= group->max_events) { event = q_overflow_event; - rc = -EOVERFLOW; + + /* + * we need to return the overflow event + * which means we need a ref + */ + fsnotify_get_event(event); + return_event = event; + /* sorry, no private data on the overflow event */ priv = NULL; } if (!list_empty(list) && merge) { - int ret; + struct fsnotify_event *tmp; - ret = merge(list, event, arg); - if (ret) { + tmp = merge(list, event); + if (tmp) { mutex_unlock(&group->notification_mutex); + + if (return_event) + fsnotify_put_event(return_event); if (holder != &event->holder) fsnotify_destroy_event_holder(holder); - return ret; + return tmp; } } @@ -197,6 +205,12 @@ alloc_holder: * event holder was used, go back and get a new one */ spin_unlock(&event->lock); mutex_unlock(&group->notification_mutex); + + if (return_event) { + fsnotify_put_event(return_event); + return_event = NULL; + } + goto alloc_holder; } @@ -211,7 +225,7 @@ alloc_holder: mutex_unlock(&group->notification_mutex); wake_up(&group->notification_waitq); - return rc; + return return_event; } /* diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h index a83859d7d36e..564b5ea4a831 100644 --- a/include/linux/fsnotify_backend.h +++ b/include/linux/fsnotify_backend.h @@ -379,13 +379,11 @@ 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, - int (*merge)(struct list_head *, - struct fsnotify_event *, - void **), - void **arg); +extern struct fsnotify_event *fsnotify_add_notify_event(struct fsnotify_group *group, + struct fsnotify_event *event, + struct fsnotify_event_private_data *priv, + struct fsnotify_event *(*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 */ |