xprtrdma: Handle stale connection rejection

A server rejects a connection attempt with STALE_CONNECTION when a
client attempts to connect to a working remote service, but uses a
QPN and GUID that corresponds to an old connection that was
abandoned. This might occur after a client crashes and restarts.

Fix rpcrdma_conn_upcall() to distinguish between a normal rejection
and rejection of stale connection parameters.

As an additional clean-up, remove the code that retries the
connection attempt with different ORD/IRD values. Code audit of
other ULP initiators shows no similar special case handling of
initiator_depth or responder_resources.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
This commit is contained in:
Chuck Lever 2017-02-08 17:00:35 -05:00 коммит произвёл Anna Schumaker
Родитель 18c0fb31a0
Коммит 0a90487bf7
1 изменённых файлов: 21 добавлений и 45 удалений

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@ -54,6 +54,7 @@
#include <linux/sunrpc/svc_rdma.h>
#include <asm/bitops.h>
#include <linux/module.h> /* try_module_get()/module_put() */
#include <rdma/ib_cm.h>
#include "xprt_rdma.h"
@ -279,7 +280,14 @@ rpcrdma_conn_upcall(struct rdma_cm_id *id, struct rdma_cm_event *event)
connstate = -ENETDOWN;
goto connected;
case RDMA_CM_EVENT_REJECTED:
#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
pr_info("rpcrdma: connection to %pIS:%u on %s rejected: %s\n",
sap, rpc_get_port(sap), ia->ri_device->name,
rdma_reject_msg(id, event->status));
#endif
connstate = -ECONNREFUSED;
if (event->status == IB_CM_REJ_STALE_CONN)
connstate = -EAGAIN;
goto connected;
case RDMA_CM_EVENT_DISCONNECTED:
connstate = -ECONNABORTED;
@ -643,20 +651,21 @@ rpcrdma_ep_destroy(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia)
int
rpcrdma_ep_connect(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia)
{
struct rpcrdma_xprt *r_xprt = container_of(ia, struct rpcrdma_xprt,
rx_ia);
struct rdma_cm_id *id, *old;
struct sockaddr *sap;
unsigned int extras;
int rc = 0;
int retry_count = 0;
if (ep->rep_connected != 0) {
struct rpcrdma_xprt *xprt;
retry:
dprintk("RPC: %s: reconnecting...\n", __func__);
rpcrdma_ep_disconnect(ep, ia);
xprt = container_of(ia, struct rpcrdma_xprt, rx_ia);
id = rpcrdma_create_id(xprt, ia,
(struct sockaddr *)&xprt->rx_data.addr);
sap = (struct sockaddr *)&r_xprt->rx_data.addr;
id = rpcrdma_create_id(r_xprt, ia, sap);
if (IS_ERR(id)) {
rc = -EHOSTUNREACH;
goto out;
@ -711,51 +720,18 @@ retry:
}
wait_event_interruptible(ep->rep_connect_wait, ep->rep_connected != 0);
/*
* Check state. A non-peer reject indicates no listener
* (ECONNREFUSED), which may be a transient state. All
* others indicate a transport condition which has already
* undergone a best-effort.
*/
if (ep->rep_connected == -ECONNREFUSED &&
++retry_count <= RDMA_CONNECT_RETRY_MAX) {
dprintk("RPC: %s: non-peer_reject, retry\n", __func__);
goto retry;
}
if (ep->rep_connected <= 0) {
/* Sometimes, the only way to reliably connect to remote
* CMs is to use same nonzero values for ORD and IRD. */
if (retry_count++ <= RDMA_CONNECT_RETRY_MAX + 1 &&
(ep->rep_remote_cma.responder_resources == 0 ||
ep->rep_remote_cma.initiator_depth !=
ep->rep_remote_cma.responder_resources)) {
if (ep->rep_remote_cma.responder_resources == 0)
ep->rep_remote_cma.responder_resources = 1;
ep->rep_remote_cma.initiator_depth =
ep->rep_remote_cma.responder_resources;
if (ep->rep_connected == -EAGAIN)
goto retry;
}
rc = ep->rep_connected;
} else {
struct rpcrdma_xprt *r_xprt;
unsigned int extras;
dprintk("RPC: %s: connected\n", __func__);
r_xprt = container_of(ia, struct rpcrdma_xprt, rx_ia);
extras = r_xprt->rx_buf.rb_bc_srv_max_requests;
if (extras) {
rc = rpcrdma_ep_post_extra_recv(r_xprt, extras);
if (rc) {
pr_warn("%s: rpcrdma_ep_post_extra_recv: %i\n",
__func__, rc);
rc = 0;
}
}
goto out;
}
dprintk("RPC: %s: connected\n", __func__);
extras = r_xprt->rx_buf.rb_bc_srv_max_requests;
if (extras)
rpcrdma_ep_post_extra_recv(r_xprt, extras);
out:
if (rc)
ep->rep_connected = rc;