NFSv41: Resend on NFS4ERR_RETRY_UNCACHED_REP

Free the slot and resend the RPC with new session <slot#,seq#>.

For nfs4_async_handle_error, return -EAGAIN and set the task->tk_status to 0
to restart the async rpc in the rpc_restart_call_prepare state which resets
the slot.

For nfs4_handle_exception, retrying a call that uses nfs4_call_sync will
reset the slot via nfs41_call_sync_prepare.

For open/close/lock/locku/delegreturn/layoutcommit/unlink/rename/write
cachethis is true, so these operations will not trigger an
NFS4ERR_RETRY_UNCACHED_REP.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

2 files changed, 8 insertions, 0 deletions

diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c
index 6f8192f4cfc7..7841ea603c91 100644
--- a/fs/nfs/nfs4filelayout.c
+++ b/fs/nfs/nfs4filelayout.c
@@ -117,6 +117,8 @@ static int filelayout_async_handle_error(struct rpc_task *task,
         case -EKEYEXPIRED:
                 rpc_delay(task, FILELAYOUT_POLL_RETRY_MAX);
                 break;
+        case -NFS4ERR_RETRY_UNCACHED_REP:
+                break;
         default:
                 dprintk("%s DS error. Retry through MDS %d\n", __func__,
                         task->tk_status);
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 69c0f3c5ee7a..cf1b339c3937 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -300,6 +300,7 @@ static int nfs4_handle_exception(struct nfs_server *server, int errorcode, struc
                         ret = nfs4_delay(server->client, &exception->timeout);
                         if (ret != 0)
                                 break;
+                case -NFS4ERR_RETRY_UNCACHED_REP:
                 case -NFS4ERR_OLD_STATEID:
                         exception->retry = 1;
                         break;
@@ -3695,6 +3696,7 @@ nfs4_async_handle_error(struct rpc_task *task, const struct nfs_server *server,
                         rpc_delay(task, NFS4_POLL_RETRY_MAX);
                         task->tk_status = 0;
                         return -EAGAIN;
+                case -NFS4ERR_RETRY_UNCACHED_REP:
                 case -NFS4ERR_OLD_STATEID:
                         task->tk_status = 0;
                         return -EAGAIN;
@@ -4844,6 +4846,8 @@ static void nfs4_get_lease_time_done(struct rpc_task *task, void *calldata)
                 dprintk("%s Retry: tk_status %d\n", __func__, task->tk_status);
                 rpc_delay(task, NFS4_POLL_RETRY_MIN);
                 task->tk_status = 0;
+                /* fall through */
+        case -NFS4ERR_RETRY_UNCACHED_REP:
                 nfs_restart_rpc(task, data->clp);
                 return;
         }
@@ -5479,6 +5483,8 @@ static int nfs41_reclaim_complete_handle_errors(struct rpc_task *task, struct nf
                 break;
         case -NFS4ERR_DELAY:
                 rpc_delay(task, NFS4_POLL_RETRY_MAX);
+                /* fall through */
+        case -NFS4ERR_RETRY_UNCACHED_REP:
                 return -EAGAIN;
         default:
                 nfs4_schedule_lease_recovery(clp);