[PATCH] SUNRPC: have soft RPC tasks return -ETIMEDOUT instead of -EIO on major connect timeout

[Jeff Layton <jlayton@redhat.com>]

NFSv4 background mounts do not currently work correctly. While we could
try to fix this in userspace, I think it's really a kernel problem...

When a soft RPC tasks experiences a major timeout during a connection
attempt, it does an rpc_exit with a return code of -EIO. For NFSv4
mounts, this makes the mount() syscall return -EIO. mount.nfs4 then
interprets that as a "permanent" error, and won't attempt a background
mount when bg is specified. Fix this by making call_timeout() do the
rpc_exit() with an error of -ETIMEDOUT.

This fixes the background mount issue, but does make other syscalls
on soft mounts return ETIMEDOUT instead of EIO in this situation.

Comments welcome.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
---
 net/sunrpc/clnt.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index 8c6a7f1..b6d409e 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -1162,7 +1162,7 @@ call_timeout(struct rpc_task *task)
 	if (RPC_IS_SOFT(task)) {
 		printk(KERN_NOTICE "%s: server %s not responding, timed out\n",
 				clnt->cl_protname, clnt->cl_server);
-		rpc_exit(task, -EIO);
+		rpc_exit(task, -ETIMEDOUT);
 		return;
 	}
 
-- 
1.5.3.6