From: Chuck Lever <chuck.lever@oracle.com>
Date: Fri, 4 May 2018 15:34:37 -0400
Subject: xprtrdma: Try to fail quickly if proto=rdma
Patch-mainline: v4.18-rc1
Git-commit: 52d28fe4f61350baf7e84b3f3f3e34f0fc077ec1
References: bsc#1103992 FATE#326009
rdma_resolve_addr(3) says:
> This call is used to map a given destination IP address to a
> usable RDMA address. The IP to RDMA address mapping is done
> using the local routing tables, or via ARP.
If this can't be done, there's no local device that can be used
to establish an RDMA-capable network path to the remote. In this
case, the RDMA CM very quickly posts an RDMA_CM_EVENT_ADDR_ERROR
upcall.
Currently rpcrdma_conn_upcall() converts RDMA_CM_EVENT_ADDR_ERROR
to EHOSTUNREACH. mount.nfs seems to want to retry EHOSTUNREACH
forever, thinking that this is a temporary situation. This makes
mount.nfs appear to hang if I try to mount with proto=rdma through,
say, a conventional Ethernet device.
If the admin has specified proto=rdma along with a server IP address
that requires a network path that does not support RDMA, instead
let's fail with a permanent error. -EPROTONOSUPPORT is returned when
NFSv4 or one of its minor versions is not supported.
-EPROTO is not (currently) retried by mount.nfs.
There are potentially other similar cases where -EPROTO is an
appropriate return code.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Olga Kornievskaia <kolga@netapp.com>
Tested-by: Anna Schumaker <Anna.Schumaker@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
net/sunrpc/xprtrdma/verbs.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/net/sunrpc/xprtrdma/verbs.c
+++ b/net/sunrpc/xprtrdma/verbs.c
@@ -233,7 +233,7 @@ rpcrdma_conn_upcall(struct rdma_cm_id *i
complete(&ia->ri_done);
break;
case RDMA_CM_EVENT_ADDR_ERROR:
- ia->ri_async_rc = -EHOSTUNREACH;
+ ia->ri_async_rc = -EPROTO;
complete(&ia->ri_done);
break;
case RDMA_CM_EVENT_ROUTE_ERROR:
@@ -264,7 +264,7 @@ rpcrdma_conn_upcall(struct rdma_cm_id *i
connstate = -ENOTCONN;
goto connected;
case RDMA_CM_EVENT_UNREACHABLE:
- connstate = -ENETDOWN;
+ connstate = -ENETUNREACH;
goto connected;
case RDMA_CM_EVENT_REJECTED:
dprintk("rpcrdma: connection to %s:%s rejected: %s\n",