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@xxxxxxxxxx>
---
net/sunrpc/xprtrdma/verbs.c | 66 ++++++++++++++-----------------------------
1 file changed, 21 insertions(+), 45 deletions(-)
diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c
index 61d16c3..d1ee33f 100644
--- a/net/sunrpc/xprtrdma/verbs.c
+++ b/net/sunrpc/xprtrdma/verbs.c
@@ -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 @@
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 @@ static void rpcrdma_destroy_id(struct rdma_cm_id *id)
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 @@ static void rpcrdma_destroy_id(struct rdma_cm_id *id)
}
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;
--
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