[PATCH 5.4 107/203] NFSv4.x: Handle bad/dead sessions correctly in nfs41_sequence_process()

From: Greg Kroah-Hartman
Date: Thu Jan 16 2020 - 18:44:41 EST


From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>

commit 5c441544f045e679afd6c3c6d9f7aaf5fa5f37b0 upstream.

If the server returns a bad or dead session error, the we don't want
to update the session slot number, but just immediately schedule
recovery and allow it to proceed.

We can/should then remove handling in other places

Fixes: 3453d5708b33 ("NFSv4.1: Avoid false retries when RPC calls are interrupted")
Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
fs/nfs/nfs4proc.c | 34 +++++++++++++++++++++++++---------
1 file changed, 25 insertions(+), 9 deletions(-)

--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -521,9 +521,7 @@ static int nfs4_do_handle_exception(stru
case -NFS4ERR_DEADSESSION:
case -NFS4ERR_SEQ_FALSE_RETRY:
case -NFS4ERR_SEQ_MISORDERED:
- dprintk("%s ERROR: %d Reset session\n", __func__,
- errorcode);
- nfs4_schedule_session_recovery(clp->cl_session, errorcode);
+ /* Handled in nfs41_sequence_process() */
goto wait_on_recovery;
#endif /* defined(CONFIG_NFS_V4_1) */
case -NFS4ERR_FILE_OPEN:
@@ -782,6 +780,7 @@ static int nfs41_sequence_process(struct
struct nfs4_session *session;
struct nfs4_slot *slot = res->sr_slot;
struct nfs_client *clp;
+ int status;
int ret = 1;

if (slot == NULL)
@@ -793,8 +792,13 @@ static int nfs41_sequence_process(struct
session = slot->table->session;

trace_nfs4_sequence_done(session, res);
+
+ status = res->sr_status;
+ if (task->tk_status == -NFS4ERR_DEADSESSION)
+ status = -NFS4ERR_DEADSESSION;
+
/* Check the SEQUENCE operation status */
- switch (res->sr_status) {
+ switch (status) {
case 0:
/* Mark this sequence number as having been acked */
nfs4_slot_sequence_acked(slot, slot->seq_nr);
@@ -866,6 +870,10 @@ static int nfs41_sequence_process(struct
*/
slot->seq_nr = slot->seq_nr_highest_sent;
goto out_retry;
+ case -NFS4ERR_BADSESSION:
+ case -NFS4ERR_DEADSESSION:
+ case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
+ goto session_recover;
default:
/* Just update the slot sequence no. */
slot->seq_done = 1;
@@ -876,8 +884,10 @@ out:
out_noaction:
return ret;
session_recover:
- nfs4_schedule_session_recovery(session, res->sr_status);
- goto retry_nowait;
+ nfs4_schedule_session_recovery(session, status);
+ dprintk("%s ERROR: %d Reset session\n", __func__, status);
+ nfs41_sequence_free_slot(res);
+ goto out;
retry_new_seq:
++slot->seq_nr;
retry_nowait:
@@ -2188,7 +2198,6 @@ static int nfs4_handle_delegation_recall
case -NFS4ERR_BAD_HIGH_SLOT:
case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
case -NFS4ERR_DEADSESSION:
- nfs4_schedule_session_recovery(server->nfs_client->cl_session, err);
return -EAGAIN;
case -NFS4ERR_STALE_CLIENTID:
case -NFS4ERR_STALE_STATEID:
@@ -7820,6 +7829,15 @@ nfs41_same_server_scope(struct nfs41_ser
static void
nfs4_bind_one_conn_to_session_done(struct rpc_task *task, void *calldata)
{
+ struct nfs41_bind_conn_to_session_args *args = task->tk_msg.rpc_argp;
+ struct nfs_client *clp = args->client;
+
+ switch (task->tk_status) {
+ case -NFS4ERR_BADSESSION:
+ case -NFS4ERR_DEADSESSION:
+ nfs4_schedule_session_recovery(clp->cl_session,
+ task->tk_status);
+ }
}

static const struct rpc_call_ops nfs4_bind_one_conn_to_session_ops = {
@@ -8867,8 +8885,6 @@ static int nfs41_reclaim_complete_handle
case -NFS4ERR_BADSESSION:
case -NFS4ERR_DEADSESSION:
case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
- nfs4_schedule_session_recovery(clp->cl_session,
- task->tk_status);
break;
default:
nfs4_schedule_lease_recovery(clp);