When testing pnfs layout, nfsd got error NFS4ERR_SEQ_MISORDERED.
It is caused by nfs return NFS4ERR_DELAY before validate_seqid(),
don't update the sequnce id, but nfsd updates the sequnce id !!!
According to RFC5661 20.9.3,
" If CB_SEQUENCE returns an error, then the state of the slot
(sequence ID, cached reply) MUST NOT change."
This patch introduce a new helper nfsd4_cb_sequence_done() for
processing more callback errors as client.
v2,
thanks Christoph's advice of adding a helper process errors as client
Signed-off-by: Kinglong Mee <kinglongmee@xxxxxxxxx>
---
fs/nfsd/nfs4callback.c | 122 +++++++++++++++++++++++++++++++++++++------------
fs/nfsd/state.h | 1 +
2 files changed, 93 insertions(+), 30 deletions(-)
diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
index ce8d3f2..6fce478 100644
--- a/fs/nfsd/nfs4callback.c
+++ b/fs/nfsd/nfs4callback.c
@@ -435,12 +435,12 @@ static int decode_cb_sequence4resok(struct xdr_stream *xdr,
*/
status = 0;
out:
- if (status)
- nfsd4_mark_cb_fault(cb->cb_clp, status);
+ cb->cb_seq_status = status;
return status;
out_overflow:
print_overflow_msg(__func__, xdr);
- return -EIO;
+ status = -EIO;
+ goto out;
}
static int decode_cb_sequence4res(struct xdr_stream *xdr,
@@ -451,8 +451,8 @@ static int decode_cb_sequence4res(struct xdr_stream *xdr,
if (cb->cb_minorversion == 0)
return 0;
- status = decode_cb_op_status(xdr, OP_CB_SEQUENCE, &cb->cb_status);
- if (unlikely(status || cb->cb_status))
+ status = decode_cb_op_status(xdr, OP_CB_SEQUENCE, &cb->cb_seq_status);
+ if (unlikely(status || cb->cb_seq_status))
return status;
return decode_cb_sequence4resok(xdr, cb);
@@ -526,7 +526,7 @@ static int nfs4_xdr_dec_cb_recall(struct rpc_rqst *rqstp,
if (cb != NULL) {
status = decode_cb_sequence4res(xdr, cb);
- if (unlikely(status || cb->cb_status))
+ if (unlikely(status || cb->cb_seq_status))
return status;
}
@@ -616,7 +616,7 @@ static int nfs4_xdr_dec_cb_layout(struct rpc_rqst *rqstp,
if (cb) {
status = decode_cb_sequence4res(xdr, cb);
- if (unlikely(status || cb->cb_status))
+ if (unlikely(status || cb->cb_seq_status))
return status;
}
return decode_cb_op_status(xdr, OP_CB_LAYOUTRECALL, &cb->cb_status);
@@ -874,6 +874,11 @@ static void nfsd4_cb_prepare(struct rpc_task *task, void *calldata)
struct nfs4_client *clp = cb->cb_clp;
u32 minorversion = clp->cl_minorversion;
+ /*
+ * cb_seq_status is only set in decode_cb_sequence4res,
+ * and so will remain 1 if an rpc level failure occurs.
+ */
+ cb->cb_seq_status = 1;
cb->cb_status = 0;
cb->cb_minorversion = minorversion;
if (minorversion) {
@@ -883,6 +888,84 @@ static void nfsd4_cb_prepare(struct rpc_task *task, void *calldata)
rpc_call_start(task);
}
+static bool nfsd4_cb_sequence_done(struct rpc_task *task, struct nfsd4_callback *cb)
+{
+ struct nfs4_client *clp = cb->cb_clp;
+ struct nfsd4_session *session = clp->cl_cb_session;
+ bool ret = true;
+
+ if (!clp->cl_minorversion) {
+ /*
+ * If the backchannel connection was shut down while this
+ * task was queued, we need to resubmit it after setting up
+ * a new backchannel connection.
+ *
+ * Note that if we lost our callback connection permanently
+ * the submission code will error out, so we don't need to
+ * handle that case here.
+ */
+ if (task->tk_flags & RPC_TASK_KILLED)
+ goto need_restart;
+
+ return true;
+ }
+
+ switch (cb->cb_seq_status) {
+ case 0:
+ /*
+ * No need for lock, access serialized in nfsd4_cb_prepare
+ *
+ * RFC5661 20.9.3
+ * If CB_SEQUENCE returns an error, then the state of the slot
+ * (sequence ID, cached reply) MUST NOT change.
+ */
+ ++session->se_cb_seq_nr;
+ break;
+ case -ESERVERFAULT:
+ ++session->se_cb_seq_nr;
+ case 1:
+ case -NFS4ERR_BADSESSION:
+ nfsd4_mark_cb_fault(cb->cb_clp, cb->cb_seq_status);
+ ret = false;
+ break;
+ case -NFS4ERR_DELAY:
+ if (!rpc_restart_call(task))
+ goto out;
+
+ rpc_delay(task, 2 * HZ);
+ return false;
+ case -NFS4ERR_BADSLOT:
+ goto retry_nowait;
+ case -NFS4ERR_SEQ_MISORDERED:
+ if (session->se_cb_seq_nr != 1) {
+ session->se_cb_seq_nr = 1;
+ goto retry_nowait;
+ }
+ break;
+ default:
+ dprintk("%s: unprocessed error %d\n", __func__,
+ cb->cb_seq_status);
+ }
+
+ clear_bit(0, &clp->cl_cb_slot_busy);
+ rpc_wake_up_next(&clp->cl_cb_waitq);
+ dprintk("%s: freed slot, new seqid=%d\n", __func__,
+ clp->cl_cb_session->se_cb_seq_nr);
+
+ if (task->tk_flags & RPC_TASK_KILLED)
+ goto need_restart;
+out:
+ return ret;
+retry_nowait:
+ if (rpc_restart_call_prepare(task))
+ ret = false;
+ goto out;
+need_restart:
+ task->tk_status = 0;
+ cb->cb_need_restart = true;
+ return false;
+}
+
static void nfsd4_cb_done(struct rpc_task *task, void *calldata)
{
struct nfsd4_callback *cb = calldata;
@@ -891,30 +974,8 @@ static void nfsd4_cb_done(struct rpc_task *task, void *calldata)
dprintk("%s: minorversion=%d\n", __func__,
clp->cl_minorversion);
- if (clp->cl_minorversion) {
- /* No need for lock, access serialized in nfsd4_cb_prepare */
- if (!task->tk_status)
- ++clp->cl_cb_session->se_cb_seq_nr;
- clear_bit(0, &clp->cl_cb_slot_busy);
- rpc_wake_up_next(&clp->cl_cb_waitq);
- dprintk("%s: freed slot, new seqid=%d\n", __func__,
- clp->cl_cb_session->se_cb_seq_nr);
- }
-
- /*
- * If the backchannel connection was shut down while this
- * task was queued, we need to resubmit it after setting up
- * a new backchannel connection.
- *
- * Note that if we lost our callback connection permanently
- * the submission code will error out, so we don't need to
- * handle that case here.
- */
- if (task->tk_flags & RPC_TASK_KILLED) {
- task->tk_status = 0;
- cb->cb_need_restart = true;
+ if (!nfsd4_cb_sequence_done(task, cb))
return;
- }
if (cb->cb_status) {
WARN_ON_ONCE(task->tk_status);
@@ -1090,6 +1151,7 @@ void nfsd4_init_cb(struct nfsd4_callback *cb, struct nfs4_client *clp,
cb->cb_msg.rpc_resp = cb;
cb->cb_ops = ops;
INIT_WORK(&cb->cb_work, nfsd4_run_cb_work);
+ cb->cb_seq_status = 1;
cb->cb_status = 0;
cb->cb_need_restart = false;
}
diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index dbc4f85..d975165 100644
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -67,6 +67,7 @@ struct nfsd4_callback {
struct rpc_message cb_msg;
struct nfsd4_callback_ops *cb_ops;
struct work_struct cb_work;
+ int cb_seq_status;
int cb_status;
bool cb_need_restart;
};
--
2.4.3
--
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