NFSv4: fix delegated locking

Arnaud Giersch reports that NFSv4 locking is broken when we hold a
delegation since commit 8e469ebd6d (NFSv4:
Don't allow posix locking against servers that don't support it).

According to Arnaud, the lock succeeds the first time he opens the file
(since we cannot do a delegated open) but then fails after we start using
delegated opens.

The following patch fixes it by ensuring that locking behaviour is
governed by a per-filesystem capability flag that is initially set, but
gets cleared if the server ever returns an OPEN without the
NFS4_OPEN_RESULT_LOCKTYPE_POSIX flag being set.

Reported-by: Arnaud Giersch <arnaud.giersch@iut-bm.univ-fcomte.fr>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
This commit is contained in:
Trond Myklebust
2010-04-11 16:48:44 -04:00
parent 2c61be0a94
commit 0df5dd4aae
3 changed files with 6 additions and 2 deletions

View File

@@ -1294,7 +1294,8 @@ static int nfs4_init_server(struct nfs_server *server,
/* Initialise the client representation from the mount data */
server->flags = data->flags;
server->caps |= NFS_CAP_ATOMIC_OPEN|NFS_CAP_CHANGE_ATTR;
server->caps |= NFS_CAP_ATOMIC_OPEN|NFS_CAP_CHANGE_ATTR|
NFS_CAP_POSIX_LOCK;
server->options = data->options;
/* Get a client record */