fsnotify: use dget_parent
Use dget_parent instead of opencoding it. This simplifies the code, but
more importanly prepares for the more complicated locking for a parent
dget in the dcache scale patch series.
It means we do grab a reference to the parent now if need to be watched,
but not with the specified mask. If this turns out to be a problem
we'll have to revisit it, but for now let's keep as much as possible
dcache internals inside dcache.[ch].
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c
index 3680242..4498a20 100644
--- a/fs/notify/fsnotify.c
+++ b/fs/notify/fsnotify.c
@@ -88,8 +88,6 @@
{
struct dentry *parent;
struct inode *p_inode;
- bool send = false;
- bool should_update_children = false;
if (!dentry)
dentry = path->dentry;
@@ -97,29 +95,12 @@
if (!(dentry->d_flags & DCACHE_FSNOTIFY_PARENT_WATCHED))
return;
- spin_lock(&dentry->d_lock);
- parent = dentry->d_parent;
+ parent = dget_parent(dentry);
p_inode = parent->d_inode;
- if (fsnotify_inode_watches_children(p_inode)) {
- if (p_inode->i_fsnotify_mask & mask) {
- dget(parent);
- send = true;
- }
- } else {
- /*
- * The parent doesn't care about events on it's children but
- * at least one child thought it did. We need to run all the
- * children and update their d_flags to let them know p_inode
- * doesn't care about them any more.
- */
- dget(parent);
- should_update_children = true;
- }
-
- spin_unlock(&dentry->d_lock);
-
- if (send) {
+ if (unlikely(!fsnotify_inode_watches_children(p_inode)))
+ __fsnotify_update_child_dentry_flags(p_inode);
+ else if (p_inode->i_fsnotify_mask & mask) {
/* we are notifying a parent so come up with the new mask which
* specifies these are events which came from a child. */
mask |= FS_EVENT_ON_CHILD;
@@ -130,13 +111,9 @@
else
fsnotify(p_inode, mask, dentry->d_inode, FSNOTIFY_EVENT_INODE,
dentry->d_name.name, 0);
- dput(parent);
}
- if (unlikely(should_update_children)) {
- __fsnotify_update_child_dentry_flags(p_inode);
- dput(parent);
- }
+ dput(parent);
}
EXPORT_SYMBOL_GPL(__fsnotify_parent);