[PATCH 5.4 174/178] xprtrdma: Fix handling of RDMA_ERROR replies

[Sasha Levin]

From: Chuck Lever <chuck.lever@xxxxxxxxxx>

commit 7b2182ec381f8ea15c7eb1266d6b5d7da620ad93 upstream.

The RPC client currently doesn't handle ERR_CHUNK replies correctly.
rpcrdma_complete_rqst() incorrectly passes a negative number to
xprt_complete_rqst() as the number of bytes copied. Instead, set
task->tk_status to the error value, and return zero bytes copied.

In these cases, return -EIO rather than -EREMOTEIO. The RPC client's
finite state machine doesn't know what to do with -EREMOTEIO.

Additional clean ups:
- Don't double-count RDMA_ERROR replies
- Remove a stale comment

Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Anna Schumaker <Anna.Schumaker@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 net/sunrpc/xprtrdma/rpc_rdma.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/net/sunrpc/xprtrdma/rpc_rdma.c b/net/sunrpc/xprtrdma/rpc_rdma.c
index ef5102b605895..c56e6cfc4a623 100644
--- a/net/sunrpc/xprtrdma/rpc_rdma.c
+++ b/net/sunrpc/xprtrdma/rpc_rdma.c
@@ -1246,8 +1246,7 @@ rpcrdma_decode_error(struct rpcrdma_xprt *r_xprt, struct rpcrdma_rep *rep,
 			be32_to_cpup(p), be32_to_cpu(rep->rr_xid));
 	}
 
-	r_xprt->rx_stats.bad_reply_count++;
-	return -EREMOTEIO;
+	return -EIO;
 }
 
 /* Perform XID lookup, reconstruction of the RPC reply, and
@@ -1284,13 +1283,11 @@ void rpcrdma_complete_rqst(struct rpcrdma_rep *rep)
 	spin_unlock(&xprt->queue_lock);
 	return;
 
-/* If the incoming reply terminated a pending RPC, the next
- * RPC call will post a replacement receive buffer as it is
- * being marshaled.
- */
 out_badheader:
 	trace_xprtrdma_reply_hdr(rep);
 	r_xprt->rx_stats.bad_reply_count++;
+	rqst->rq_task->tk_status = status;
+	status = 0;
 	goto out;
 }
 
-- 
2.25.1