[PATCH v5 6/7] nfsd: handle CB_SEQUENCE NFS4ERR_SEQ_MISORDERED error better

[Jeff Layton]

For NFS4ERR_SEQ_MISORDERED, do one attempt with a seqid of 1, and then
fall back to treating it like a BADSLOT if that fails.

Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
---
 fs/nfsd/nfs4callback.c | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
index 10067a34db3afff8d4e4383854ab9abd9767c2d6..d6e3e8bb2efabadda9f922318880e12e1cb2c23f 100644
--- a/fs/nfsd/nfs4callback.c
+++ b/fs/nfsd/nfs4callback.c
@@ -1393,6 +1393,16 @@ static bool nfsd4_cb_sequence_done(struct rpc_task *task, struct nfsd4_callback
 			goto requeue;
 		rpc_delay(task, 2 * HZ);
 		return false;
+	case -NFS4ERR_SEQ_MISORDERED:
+		/*
+		 * Reattempt once with seq_nr 1. If that fails, treat this
+		 * like BADSLOT.
+		 */
+		if (session->se_cb_seq_nr[cb->cb_held_slot] != 1) {
+			session->se_cb_seq_nr[cb->cb_held_slot] = 1;
+			goto retry_nowait;
+		}
+		fallthrough;
 	case -NFS4ERR_BADSLOT:
 		/*
 		 * BADSLOT means that the client and server are out of sync
@@ -1403,12 +1413,6 @@ static bool nfsd4_cb_sequence_done(struct rpc_task *task, struct nfsd4_callback
 		nfsd4_mark_cb_fault(cb->cb_clp);
 		cb->cb_held_slot = -1;
 		goto retry_nowait;
-	case -NFS4ERR_SEQ_MISORDERED:
-		if (session->se_cb_seq_nr[cb->cb_held_slot] != 1) {
-			session->se_cb_seq_nr[cb->cb_held_slot] = 1;
-			goto retry_nowait;
-		}
-		break;
 	default:
 		nfsd4_mark_cb_fault(cb->cb_clp);
 	}

-- 
2.48.1