From 7a89f9c626e337ba6528d8a2829b228c933877fb Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Wed, 29 Jun 2016 13:53:43 -0400 Subject: xprtrdma: Honor ->send_request API contract Commit c93c62231cf5 ("xprtrdma: Disconnect on registration failure") added a disconnect for some RPC marshaling failures. This is needed only in a handful of cases, but it was triggering for simple stuff like temporary resource shortages. Try to straighten this out. Fix up the lower layers so they don't return -ENOMEM or other error codes that the RPC client's FSM doesn't explicitly recognize. Also fix up the places in the send_request path that do want a disconnect. For example, when ib_post_send or ib_post_recv fail, this is a sign that there is a send or receive queue resource miscalculation. That should be rare, and is a sign of a software bug. But xprtrdma can recover: disconnect to reset the transport and start over. Signed-off-by: Chuck Lever Tested-by: Steve Wise Signed-off-by: Anna Schumaker --- net/sunrpc/xprtrdma/transport.c | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-) (limited to 'net/sunrpc/xprtrdma/transport.c') diff --git a/net/sunrpc/xprtrdma/transport.c b/net/sunrpc/xprtrdma/transport.c index 4c8e7f11b906..be4dd2c7c680 100644 --- a/net/sunrpc/xprtrdma/transport.c +++ b/net/sunrpc/xprtrdma/transport.c @@ -558,7 +558,6 @@ out_sendbuf: out_fail: rpcrdma_buffer_put(req); - r_xprt->rx_stats.failed_marshal_count++; return NULL; } @@ -590,8 +589,19 @@ xprt_rdma_free(void *buffer) rpcrdma_buffer_put(req); } -/* +/** + * xprt_rdma_send_request - marshal and send an RPC request + * @task: RPC task with an RPC message in rq_snd_buf + * + * Return values: + * 0: The request has been sent + * ENOTCONN: Caller needs to invoke connect logic then call again + * ENOBUFS: Call again later to send the request + * EIO: A permanent error occurred. The request was not sent, + * and don't try it again + * * send_request invokes the meat of RPC RDMA. It must do the following: + * * 1. Marshal the RPC request into an RPC RDMA request, which means * putting a header in front of data, and creating IOVs for RDMA * from those in the request. @@ -600,7 +610,6 @@ xprt_rdma_free(void *buffer) * the request (rpcrdma_ep_post). * 4. No partial sends are possible in the RPC-RDMA protocol (as in UDP). */ - static int xprt_rdma_send_request(struct rpc_task *task) { @@ -630,11 +639,12 @@ xprt_rdma_send_request(struct rpc_task *task) return 0; failed_marshal: - r_xprt->rx_stats.failed_marshal_count++; dprintk("RPC: %s: rpcrdma_marshal_req failed, status %i\n", __func__, rc); if (rc == -EIO) - return -EIO; + r_xprt->rx_stats.failed_marshal_count++; + if (rc != -ENOTCONN) + return rc; drop_connection: xprt_disconnect_done(xprt); return -ENOTCONN; /* implies disconnect */ -- cgit v1.2.3