ksmbd: call ib_drain_qp when disconnected

When disconnected, call ib_drain_qp to cancel all pending work requests
and prevent ksmbd_conn_handler_loop from waiting for a long time
for those work requests to compelete.
Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Reviewed-by: Tom Talpey <tom@talpey.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

fs/ksmbd/transport_rdma.c

@@ -1527,6 +1527,8 @@ static int smb_direct_cm_handler(struct rdma_cm_id *cm_id,
 	}
 	case RDMA_CM_EVENT_DEVICE_REMOVAL:
 	case RDMA_CM_EVENT_DISCONNECTED: {
+		ib_drain_qp(t->qp);
+
 		t->status = SMB_DIRECT_CS_DISCONNECTED;
 		wake_up_interruptible(&t->wait_status);
 		wake_up_interruptible(&t->wait_reassembly_queue);