exportfs: more detailed comment for path_reconnect

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
J. Bruce Fields 2013-10-22 20:59:19 -04:00 committed by Al Viro
parent 854ff5caab
commit 78cee9a8e4

View File

@ -93,7 +93,19 @@ find_disconnected_root(struct dentry *dentry)
/*
* Make sure target_dir is fully connected to the dentry tree.
*
* It may already be, as the flag isn't always updated when connection happens.
* On successful return, DCACHE_DISCONNECTED will be cleared on
* target_dir, and target_dir->d_parent->...->d_parent will reach the
* root of the filesystem.
*
* Whenever DCACHE_DISCONNECTED is unset, target_dir is fully connected.
* But the converse is not true: target_dir may have DCACHE_DISCONNECTED
* set but already be connected. In that case we'll verify the
* connection to root and then clear the flag.
*
* Note that target_dir could be removed by a concurrent operation. In
* that case reconnect_path may still succeed with target_dir fully
* connected, but further operations using the filehandle will fail when
* necessary (due to S_DEAD being set on the directory).
*/
static int
reconnect_path(struct vfsmount *mnt, struct dentry *target_dir, char *nbuf)