[PATCH v3 4/4] smb: client: relax WARN_ON_ONCE(SMBDIRECT_SOCKET_*) checks in recv_done() and smbd_conn_upcall()

[Stefan Metzmacher]

sc->first_error might already be set and sc->status
is thus unexpected, so this should avoid the WARN[_ON]_ONCE()
if sc->first_error is already set and have a usable error path.

While there set sc->first_error as soon as possible.

This is done based on a problem seen in similar places on
the server. And there it was already very useful in order
to find the problem when we have a meaningful WARN_ONCE()
that prints details about the connection.

This is much more useful:

[  309.560973] expected[NEGOTIATE_NEEDED] != RDMA_CONNECT_RUNNING
first_error=0 local=192.168.0.200:445 remote=192.168.0.100:60445
[  309.561034] WARNING: CPU: 2 PID: 78 at transport_rdma.c:643
recv_done+0x2fa/0x3d0 [ksmbd]

than what we had before (only):

[  894.140316] WARNING: CPU: 1 PID: 116 at
fs/smb/server/transport_rdma.c:642 recv_done+0x308/0x360 [ksmbd]

Fixes: 58dfba8a2d4e ("smb: client/smbdirect: replace SMBDIRECT_SOCKET_CONNECTING with more detailed states")
Cc: Steve French <smfrench at gmail.com>
Cc: Tom Talpey <tom at talpey.com>
Cc: Long Li <longli at microsoft.com>
Cc: Namjae Jeon <linkinjeon at kernel.org>
Cc: Paulo Alcantara <pc at manguebit.org>
Cc: linux-cifs at vger.kernel.org
Cc: samba-technical at lists.samba.org
Signed-off-by: Stefan Metzmacher <metze at samba.org>
---
 fs/smb/client/smbdirect.c | 28 +++++++++++++++-------------
 1 file changed, 15 insertions(+), 13 deletions(-)

diff --git a/fs/smb/client/smbdirect.c b/fs/smb/client/smbdirect.c
index c6c428c2e08d..788a0670c4a8 100644
--- a/fs/smb/client/smbdirect.c
+++ b/fs/smb/client/smbdirect.c
@@ -7,6 +7,7 @@
 #include <linux/module.h>
 #include <linux/highmem.h>
 #include <linux/folio_queue.h>
+#define __SMBDIRECT_SOCKET_DISCONNECT(__sc) smbd_disconnect_rdma_connection(__sc)
 #include "../common/smbdirect/smbdirect_pdu.h"
 #include "smbdirect.h"
 #include "cifs_debug.h"
@@ -186,6 +187,9 @@ static void smbd_disconnect_rdma_work(struct work_struct *work)
 	struct smbdirect_socket *sc =
 		container_of(work, struct smbdirect_socket, disconnect_work);
 
+	if (sc->first_error == 0)
+		sc->first_error = -ECONNABORTED;
+
 	/*
 	 * make sure this and other work is not queued again
 	 * but here we don't block and avoid
@@ -197,9 +201,6 @@ static void smbd_disconnect_rdma_work(struct work_struct *work)
 	disable_work(&sc->idle.immediate_work);
 	disable_delayed_work(&sc->idle.timer_work);
 
-	if (sc->first_error == 0)
-		sc->first_error = -ECONNABORTED;
-
 	switch (sc->status) {
 	case SMBDIRECT_SOCKET_NEGOTIATE_NEEDED:
 	case SMBDIRECT_SOCKET_NEGOTIATE_RUNNING:
@@ -242,6 +243,9 @@ static void smbd_disconnect_rdma_work(struct work_struct *work)
 
 static void smbd_disconnect_rdma_connection(struct smbdirect_socket *sc)
 {
+	if (sc->first_error == 0)
+		sc->first_error = -ECONNABORTED;
+
 	/*
 	 * make sure other work (than disconnect_work) is
 	 * not queued again but here we don't block and avoid
@@ -252,9 +256,6 @@ static void smbd_disconnect_rdma_connection(struct smbdirect_socket *sc)
 	disable_work(&sc->idle.immediate_work);
 	disable_delayed_work(&sc->idle.timer_work);
 
-	if (sc->first_error == 0)
-		sc->first_error = -ECONNABORTED;
-
 	switch (sc->status) {
 	case SMBDIRECT_SOCKET_RESOLVE_ADDR_FAILED:
 	case SMBDIRECT_SOCKET_RESOLVE_ROUTE_FAILED:
@@ -322,27 +323,27 @@ static int smbd_conn_upcall(
 
 	switch (event->event) {
 	case RDMA_CM_EVENT_ADDR_RESOLVED:
-		WARN_ON_ONCE(sc->status != SMBDIRECT_SOCKET_RESOLVE_ADDR_RUNNING);
+		if (SMBDIRECT_CHECK_STATUS_DISCONNECT(sc, SMBDIRECT_SOCKET_RESOLVE_ADDR_RUNNING))
+			break;
 		sc->status = SMBDIRECT_SOCKET_RESOLVE_ROUTE_NEEDED;
 		wake_up(&sc->status_wait);
 		break;
 
 	case RDMA_CM_EVENT_ROUTE_RESOLVED:
-		WARN_ON_ONCE(sc->status != SMBDIRECT_SOCKET_RESOLVE_ROUTE_RUNNING);
+		if (SMBDIRECT_CHECK_STATUS_DISCONNECT(sc, SMBDIRECT_SOCKET_RESOLVE_ROUTE_RUNNING))
+			break;
 		sc->status = SMBDIRECT_SOCKET_RDMA_CONNECT_NEEDED;
 		wake_up(&sc->status_wait);
 		break;
 
 	case RDMA_CM_EVENT_ADDR_ERROR:
 		log_rdma_event(ERR, "connecting failed event=%s\n", event_name);
-		WARN_ON_ONCE(sc->status != SMBDIRECT_SOCKET_RESOLVE_ADDR_RUNNING);
 		sc->status = SMBDIRECT_SOCKET_RESOLVE_ADDR_FAILED;
 		smbd_disconnect_rdma_work(&sc->disconnect_work);
 		break;
 
 	case RDMA_CM_EVENT_ROUTE_ERROR:
 		log_rdma_event(ERR, "connecting failed event=%s\n", event_name);
-		WARN_ON_ONCE(sc->status != SMBDIRECT_SOCKET_RESOLVE_ROUTE_RUNNING);
 		sc->status = SMBDIRECT_SOCKET_RESOLVE_ROUTE_FAILED;
 		smbd_disconnect_rdma_work(&sc->disconnect_work);
 		break;
@@ -428,7 +429,8 @@ static int smbd_conn_upcall(
 					min_t(u8, sp->responder_resources,
 					      peer_responder_resources);
 
-		WARN_ON_ONCE(sc->status != SMBDIRECT_SOCKET_RDMA_CONNECT_RUNNING);
+		if (SMBDIRECT_CHECK_STATUS_DISCONNECT(sc, SMBDIRECT_SOCKET_RDMA_CONNECT_RUNNING))
+			break;
 		sc->status = SMBDIRECT_SOCKET_NEGOTIATE_NEEDED;
 		wake_up(&sc->status_wait);
 		break;
@@ -437,7 +439,6 @@ static int smbd_conn_upcall(
 	case RDMA_CM_EVENT_UNREACHABLE:
 	case RDMA_CM_EVENT_REJECTED:
 		log_rdma_event(ERR, "connecting failed event=%s\n", event_name);
-		WARN_ON_ONCE(sc->status != SMBDIRECT_SOCKET_RDMA_CONNECT_RUNNING);
 		sc->status = SMBDIRECT_SOCKET_RDMA_CONNECT_FAILED;
 		smbd_disconnect_rdma_work(&sc->disconnect_work);
 		break;
@@ -699,7 +700,8 @@ static void recv_done(struct ib_cq *cq, struct ib_wc *wc)
 		negotiate_done =
 			process_negotiation_response(response, wc->byte_len);
 		put_receive_buffer(sc, response);
-		WARN_ON_ONCE(sc->status != SMBDIRECT_SOCKET_NEGOTIATE_RUNNING);
+		if (SMBDIRECT_CHECK_STATUS_WARN(sc, SMBDIRECT_SOCKET_NEGOTIATE_RUNNING))
+			negotiate_done = false;
 		if (!negotiate_done) {
 			sc->status = SMBDIRECT_SOCKET_NEGOTIATE_FAILED;
 			smbd_disconnect_rdma_connection(sc);
-- 
2.43.0