diff options
Diffstat (limited to 'fs/notify')
| -rw-r--r-- | fs/notify/group.c | 28 | ||||
| -rw-r--r-- | fs/notify/inotify/inotify_fsnotify.c | 2 | ||||
| -rw-r--r-- | fs/notify/inotify/inotify_user.c | 1 | ||||
| -rw-r--r-- | fs/notify/mark.c | 24 |
4 files changed, 27 insertions, 28 deletions
diff --git a/fs/notify/group.c b/fs/notify/group.c index 1d57c35f1043..354044c47e23 100644 --- a/fs/notify/group.c +++ b/fs/notify/group.c @@ -33,9 +33,6 @@ */ void fsnotify_final_destroy_group(struct fsnotify_group *group) { - /* clear the notification queue of all events */ - fsnotify_flush_notify(group); - if (group->ops->free_group_priv) group->ops->free_group_priv(group); @@ -43,12 +40,10 @@ void fsnotify_final_destroy_group(struct fsnotify_group *group) } /* - * Trying to get rid of a group. We need to first get rid of any outstanding - * allocations and then free the group. Remember that fsnotify_clear_marks_by_group - * could miss marks that are being freed by inode and those marks could still - * hold a reference to this group (via group->num_marks) If we get into that - * situtation, the fsnotify_final_destroy_group will get called when that final - * mark is freed. + * Trying to get rid of a group. Remove all marks, flush all events and release + * the group reference. + * Note that another thread calling fsnotify_clear_marks_by_group() may still + * hold a ref to the group. */ void fsnotify_destroy_group(struct fsnotify_group *group) { @@ -57,9 +52,10 @@ void fsnotify_destroy_group(struct fsnotify_group *group) synchronize_srcu(&fsnotify_mark_srcu); - /* past the point of no return, matches the initial value of 1 */ - if (atomic_dec_and_test(&group->num_marks)) - fsnotify_final_destroy_group(group); + /* clear the notification queue of all events */ + fsnotify_flush_notify(group); + + fsnotify_put_group(group); } /* @@ -76,7 +72,7 @@ void fsnotify_get_group(struct fsnotify_group *group) void fsnotify_put_group(struct fsnotify_group *group) { if (atomic_dec_and_test(&group->refcnt)) - fsnotify_destroy_group(group); + fsnotify_final_destroy_group(group); } /* @@ -92,11 +88,7 @@ struct fsnotify_group *fsnotify_alloc_group(const struct fsnotify_ops *ops) /* set to 0 when there a no external references to this group */ atomic_set(&group->refcnt, 1); - /* - * hits 0 when there are no external references AND no marks for - * this group - */ - atomic_set(&group->num_marks, 1); + atomic_set(&group->num_marks, 0); mutex_init(&group->notification_mutex); INIT_LIST_HEAD(&group->notification_list); diff --git a/fs/notify/inotify/inotify_fsnotify.c b/fs/notify/inotify/inotify_fsnotify.c index e3cbd746f64a..74977fbf5aae 100644 --- a/fs/notify/inotify/inotify_fsnotify.c +++ b/fs/notify/inotify/inotify_fsnotify.c @@ -118,6 +118,7 @@ static int inotify_handle_event(struct fsnotify_group *group, fsn_event_priv = &event_priv->fsnotify_event_priv_data; + fsnotify_get_group(group); fsn_event_priv->group = group; event_priv->wd = wd; @@ -210,6 +211,7 @@ void inotify_free_event_priv(struct fsnotify_event_private_data *fsn_event_priv) event_priv = container_of(fsn_event_priv, struct inotify_event_private_data, fsnotify_event_priv_data); + fsnotify_put_group(fsn_event_priv->group); kmem_cache_free(event_priv_cachep, event_priv); } diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c index dbafbfc8ceca..246250f1db7a 100644 --- a/fs/notify/inotify/inotify_user.c +++ b/fs/notify/inotify/inotify_user.c @@ -531,6 +531,7 @@ void inotify_ignored_and_remove_idr(struct fsnotify_mark *fsn_mark, fsn_event_priv = &event_priv->fsnotify_event_priv_data; + fsnotify_get_group(group); fsn_event_priv->group = group; event_priv->wd = i_mark->wd; diff --git a/fs/notify/mark.c b/fs/notify/mark.c index f104d565b682..3c7a1699df3d 100644 --- a/fs/notify/mark.c +++ b/fs/notify/mark.c @@ -109,8 +109,11 @@ void fsnotify_get_mark(struct fsnotify_mark *mark) void fsnotify_put_mark(struct fsnotify_mark *mark) { - if (atomic_dec_and_test(&mark->refcnt)) + if (atomic_dec_and_test(&mark->refcnt)) { + if (mark->group) + fsnotify_put_group(mark->group); mark->free_mark(mark); + } } /* @@ -125,12 +128,13 @@ void fsnotify_destroy_mark(struct fsnotify_mark *mark) spin_lock(&mark->lock); + fsnotify_get_group(mark->group); group = mark->group; /* something else already called this function on this mark */ if (!(mark->flags & FSNOTIFY_MARK_FLAG_ALIVE)) { spin_unlock(&mark->lock); - return; + goto put_group; } mark->flags &= ~FSNOTIFY_MARK_FLAG_ALIVE; @@ -177,19 +181,15 @@ void fsnotify_destroy_mark(struct fsnotify_mark *mark) if (inode && (mark->flags & FSNOTIFY_MARK_FLAG_OBJECT_PINNED)) iput(inode); - /* * We don't necessarily have a ref on mark from caller so the above iput * may have already destroyed it. Don't touch from now on. */ - /* - * it's possible that this group tried to destroy itself, but this - * this mark was simultaneously being freed by inode. If that's the - * case, we finish freeing the group here. - */ - if (unlikely(atomic_dec_and_test(&group->num_marks))) - fsnotify_final_destroy_group(group); + atomic_dec(&group->num_marks); + +put_group: + fsnotify_put_group(group); } void fsnotify_set_mark_mask_locked(struct fsnotify_mark *mark, __u32 mask) @@ -234,6 +234,7 @@ int fsnotify_add_mark(struct fsnotify_mark *mark, mark->flags |= FSNOTIFY_MARK_FLAG_ALIVE; + fsnotify_get_group(group); mark->group = group; list_add(&mark->g_list, &group->marks_list); atomic_inc(&group->num_marks); @@ -265,6 +266,7 @@ int fsnotify_add_mark(struct fsnotify_mark *mark, err: mark->flags &= ~FSNOTIFY_MARK_FLAG_ALIVE; list_del_init(&mark->g_list); + fsnotify_put_group(group); mark->group = NULL; atomic_dec(&group->num_marks); @@ -317,6 +319,8 @@ void fsnotify_duplicate_mark(struct fsnotify_mark *new, struct fsnotify_mark *ol assert_spin_locked(&old->lock); new->i.inode = old->i.inode; new->m.mnt = old->m.mnt; + if (old->group) + fsnotify_get_group(old->group); new->group = old->group; new->mask = old->mask; new->free_mark = old->free_mark; |