[ 108/128] NFSv4.1: Handle NFS4ERR_DELAY when resetting the NFSv4.1 session

Ben Hutchings
2013-02-03T15:04:03Z

From: Trond Myklebust <Trond.Myklebust@netapp.com>

commit c489ee290bdbbace6bb63ebe6ebd4dd605819495 upstream.

NFS4ERR_DELAY is a legal reply when we call DESTROY_SESSION. It
usually means that the server is busy handling an unfinished RPC
request. Just sleep for a second and then retry.
We also need to be able to handle the NFS4ERR_BACK_CHAN_BUSY return
value. If the NFS server has outstanding callbacks, we just want to
similarly sleep & retry.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
fs/nfs/nfs4state.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)

--- a/fs/nfs/nfs4state.c
+++ b/fs/nfs/nfs4state.c
@@ -1583,8 +1583,18 @@ static int nfs4_reset_session(struct nfs

nfs4_begin_drain_session(clp);
status = nfs4_proc_destroy_session(clp->cl_session);
- if (status && status != -NFS4ERR_BADSESSION &&
- status != -NFS4ERR_DEADSESSION) {
+ switch (status) {
+ case 0:
+ case -NFS4ERR_BADSESSION:
+ case -NFS4ERR_DEADSESSION:
+ break;
+ case -NFS4ERR_BACK_CHAN_BUSY:
+ case -NFS4ERR_DELAY:
+ set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
+ status = 0;
+ ssleep(1);
+ goto out;
+ default:
status = nfs4_recovery_handle_error(clp, status);
goto out;
}