tree da4ab8077cc3d9dce5b6ec2d003074cba3841446
parent 50ee93afcaa970620d1fb5a9894109a2ab152868
author Miklos Szeredi <mszeredi@suse.cz> 1337614219 +0200
committer Al Viro <viro@zeniv.linux.org.uk> 1338567121 -0400

vfs: retry last component if opening stale dentry

NFS optimizes away d_revalidates for last component of open.  This means that
open itself can find the dentry stale.

This patch allows the filesystem to return EOPENSTALE and the VFS will retry the
lookup on just the last component if possible.

If the lookup was done using RCU mode, including the last component, then this
is not possible since the parent dentry is lost.  In this case fall back to
non-RCU lookup.  Currently this is not used since NFS will always leave RCU
mode.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>