NFS: Migration support for RELEASE_LOCKOWNER
Currently the Linux NFS client ignores the operation status code for
the RELEASE_LOCKOWNER operation. Like NFSv3's UMNT operation,
RELEASE_LOCKOWNER is a courtesy to help servers manage their
resources, and the outcome is not consequential for the client.
During a migration, a server may report NFS4ERR_LEASE_MOVED, in
which case the client really should retry, since typically
LEASE_MOVED has nothing to do with the current operation, but does
prevent it from going forward.
Also, it's important for a client to respond as soon as possible to
a moved lease condition, since the client's lease could expire on
the destination without further action by the client.
NFS4ERR_DELAY is not included in the list of valid status codes for
RELEASE_LOCKOWNER in RFC 3530bis. However, rfc3530-migration-update
does permit migration-capable servers to return DELAY to clients,
but only in the context of an ongoing migration. In this case the
server has frozen lock state in preparation for migration, and a
client retry would help the destination server purge unneeded state
once migration recovery is complete.
Interestly, NFS4ERR_MOVED is not valid for RELEASE_LOCKOWNER, even
though lock owners can be migrated with Transparent State Migration.
Note that RFC 3530bis section 9.5 includes RELEASE_LOCKOWNER in the
list of operations that renew a client's lease on the server if they
succeed. Now that our client pays attention to the operation's
status code, we can note that renewal appropriately.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 2564e1c..9f2ccf7 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -5800,6 +5800,7 @@
struct nfs_release_lockowner_args args;
struct nfs4_sequence_args seq_args;
struct nfs4_sequence_res seq_res;
+ unsigned long timestamp;
};
static void nfs4_release_lockowner_prepare(struct rpc_task *task, void *calldata)
@@ -5807,12 +5808,27 @@
struct nfs_release_lockowner_data *data = calldata;
nfs40_setup_sequence(data->server,
&data->seq_args, &data->seq_res, task);
+ data->timestamp = jiffies;
}
static void nfs4_release_lockowner_done(struct rpc_task *task, void *calldata)
{
struct nfs_release_lockowner_data *data = calldata;
+ struct nfs_server *server = data->server;
+
nfs40_sequence_done(task, &data->seq_res);
+
+ switch (task->tk_status) {
+ case 0:
+ renew_lease(server, data->timestamp);
+ break;
+ case -NFS4ERR_STALE_CLIENTID:
+ case -NFS4ERR_EXPIRED:
+ case -NFS4ERR_LEASE_MOVED:
+ case -NFS4ERR_DELAY:
+ if (nfs4_async_handle_error(task, server, NULL) == -EAGAIN)
+ rpc_restart_call_prepare(task);
+ }
}
static void nfs4_release_lockowner_release(void *calldata)