[PATCH 2/7] cifs: smbd: Don't destroy transport on RDMA disconnect

[Long Li]

From: Long Li <longli@xxxxxxxxxxxxx>

Now upper layer is handling the transport shutdown and reconnect, remove
the code that handling transport shutdown on RDMA disconnect.

Signed-off-by: Long Li <longli@xxxxxxxxxxxxx>
---
 fs/cifs/cifs_debug.c |   8 ++--
 fs/cifs/smbdirect.c  | 122 ++++-----------------------------------------------
 fs/cifs/smbdirect.h  |   9 ----
 3 files changed, 11 insertions(+), 128 deletions(-)

diff --git a/fs/cifs/cifs_debug.c b/fs/cifs/cifs_debug.c
index e6025e9..0337ee8 100644
--- a/fs/cifs/cifs_debug.c
+++ b/fs/cifs/cifs_debug.c
@@ -214,12 +214,10 @@ static int cifs_debug_data_proc_show(struct seq_file *m, void *v)
 			atomic_read(&server->smbd_conn->send_credits),
 			atomic_read(&server->smbd_conn->receive_credits),
 			server->smbd_conn->receive_credit_target);
-		seq_printf(m, "\nPending send_pending: %x send_payload_pending:"
-			" %x smbd_send_pending: %x smbd_recv_pending: %x",
+		seq_printf(m, "\nPending send_pending: %x "
+			"send_payload_pending: %x",
 			atomic_read(&server->smbd_conn->send_pending),
-			atomic_read(&server->smbd_conn->send_payload_pending),
-			server->smbd_conn->smbd_send_pending,
-			server->smbd_conn->smbd_recv_pending);
+			atomic_read(&server->smbd_conn->send_payload_pending));
 		seq_printf(m, "\nReceive buffers count_receive_queue: %x "
 			"count_empty_packet_queue: %x",
 			server->smbd_conn->count_receive_queue,
diff --git a/fs/cifs/smbdirect.c b/fs/cifs/smbdirect.c
index 1aa2d35..79b025e 100644
--- a/fs/cifs/smbdirect.c
+++ b/fs/cifs/smbdirect.c
@@ -162,95 +162,6 @@ do {									\
 #define log_rdma_mr(level, fmt, args...) \
 		log_rdma(level, LOG_RDMA_MR, fmt, ##args)
 
-/*
- * Destroy the transport and related RDMA and memory resources
- * Need to go through all the pending counters and make sure on one is using
- * the transport while it is destroyed
- */
-static void smbd_destroy_rdma_work(struct work_struct *work)
-{
-	struct smbd_response *response;
-	struct smbd_connection *info =
-		container_of(work, struct smbd_connection, destroy_work);
-	unsigned long flags;
-
-	log_rdma_event(INFO, "destroying qp\n");
-	ib_drain_qp(info->id->qp);
-	rdma_destroy_qp(info->id);
-
-	/* Unblock all I/O waiting on the send queue */
-	wake_up_interruptible_all(&info->wait_send_queue);
-
-	log_rdma_event(INFO, "cancelling idle timer\n");
-	cancel_delayed_work_sync(&info->idle_timer_work);
-	log_rdma_event(INFO, "cancelling send immediate work\n");
-	cancel_delayed_work_sync(&info->send_immediate_work);
-
-	log_rdma_event(INFO, "wait for all send to finish\n");
-	wait_event(info->wait_smbd_send_pending,
-		info->smbd_send_pending == 0);
-
-	log_rdma_event(INFO, "wait for all recv to finish\n");
-	wake_up_interruptible(&info->wait_reassembly_queue);
-	wait_event(info->wait_smbd_recv_pending,
-		info->smbd_recv_pending == 0);
-
-	log_rdma_event(INFO, "wait for all send posted to IB to finish\n");
-	wait_event(info->wait_send_pending,
-		atomic_read(&info->send_pending) == 0);
-	wait_event(info->wait_send_payload_pending,
-		atomic_read(&info->send_payload_pending) == 0);
-
-	log_rdma_event(INFO, "freeing mr list\n");
-	wake_up_interruptible_all(&info->wait_mr);
-	wait_event(info->wait_for_mr_cleanup,
-		atomic_read(&info->mr_used_count) == 0);
-	destroy_mr_list(info);
-
-	/* It's not posssible for upper layer to get to reassembly */
-	log_rdma_event(INFO, "drain the reassembly queue\n");
-	do {
-		spin_lock_irqsave(&info->reassembly_queue_lock, flags);
-		response = _get_first_reassembly(info);
-		if (response) {
-			list_del(&response->list);
-			spin_unlock_irqrestore(
-				&info->reassembly_queue_lock, flags);
-			put_receive_buffer(info, response);
-		} else
-			spin_unlock_irqrestore(&info->reassembly_queue_lock, flags);
-	} while (response);
-
-	info->reassembly_data_length = 0;
-
-	log_rdma_event(INFO, "free receive buffers\n");
-	wait_event(info->wait_receive_queues,
-		info->count_receive_queue + info->count_empty_packet_queue
-			== info->receive_credit_max);
-	destroy_receive_buffers(info);
-
-	ib_free_cq(info->send_cq);
-	ib_free_cq(info->recv_cq);
-	ib_dealloc_pd(info->pd);
-	rdma_destroy_id(info->id);
-
-	/* free mempools */
-	mempool_destroy(info->request_mempool);
-	kmem_cache_destroy(info->request_cache);
-
-	mempool_destroy(info->response_mempool);
-	kmem_cache_destroy(info->response_cache);
-
-	info->transport_status = SMBD_DESTROYED;
-	wake_up_all(&info->wait_destroy);
-}
-
-static int smbd_process_disconnected(struct smbd_connection *info)
-{
-	schedule_work(&info->destroy_work);
-	return 0;
-}
-
 static void smbd_disconnect_rdma_work(struct work_struct *work)
 {
 	struct smbd_connection *info =
@@ -317,8 +228,7 @@ static int smbd_conn_upcall(
 		}
 
 		info->transport_status = SMBD_DISCONNECTED;
-		smbd_process_disconnected(info);
-		wake_up(&info->disconn_wait);
+		wake_up_interruptible(&info->disconn_wait);
 		wake_up_interruptible(&info->wait_reassembly_queue);
 		wake_up_interruptible_all(&info->wait_send_queue);
 		break;
@@ -1499,7 +1409,7 @@ void smbd_destroy(struct TCP_Server_Info *server)
 	if (info->transport_status != SMBD_DISCONNECTED) {
 		rdma_disconnect(server->smbd_conn->id);
 		log_rdma_event(INFO, "wait for transport being disconnected\n");
-		wait_event(
+		wait_event_interruptible(
 			info->disconn_wait,
 			info->transport_status == SMBD_DISCONNECTED);
 	}
@@ -1840,12 +1750,6 @@ static struct smbd_connection *_smbd_get_connection(
 	queue_delayed_work(info->workqueue, &info->idle_timer_work,
 		info->keep_alive_interval*HZ);
 
-	init_waitqueue_head(&info->wait_smbd_send_pending);
-	info->smbd_send_pending = 0;
-
-	init_waitqueue_head(&info->wait_smbd_recv_pending);
-	info->smbd_recv_pending = 0;
-
 	init_waitqueue_head(&info->wait_send_pending);
 	atomic_set(&info->send_pending, 0);
 
@@ -1853,7 +1757,6 @@ static struct smbd_connection *_smbd_get_connection(
 	atomic_set(&info->send_payload_pending, 0);
 
 	INIT_WORK(&info->disconnect_work, smbd_disconnect_rdma_work);
-	INIT_WORK(&info->destroy_work, smbd_destroy_rdma_work);
 	INIT_WORK(&info->recv_done_work, smbd_recv_done_work);
 	INIT_WORK(&info->post_send_credits_work, smbd_post_send_credits);
 	info->new_credits_offered = 0;
@@ -1947,11 +1850,6 @@ static int smbd_recv_buf(struct smbd_connection *info, char *buf,
 	int rc;
 
 again:
-	if (info->transport_status != SMBD_CONNECTED) {
-		log_read(ERR, "disconnected\n");
-		return -ENODEV;
-	}
-
 	/*
 	 * No need to hold the reassembly queue lock all the time as we are
 	 * the only one reading from the front of the queue. The transport
@@ -2067,6 +1965,11 @@ static int smbd_recv_buf(struct smbd_connection *info, char *buf,
 	if (rc)
 		return -ENODEV;
 
+	if (info->transport_status != SMBD_CONNECTED) {
+		log_read(ERR, "disconnected\n");
+		return 0;
+	}
+
 	goto again;
 }
 
@@ -2114,8 +2017,6 @@ int smbd_recv(struct smbd_connection *info, struct msghdr *msg)
 	unsigned int to_read;
 	int rc;
 
-	info->smbd_recv_pending++;
-
 	switch (msg->msg_iter.type) {
 	case READ | ITER_KVEC:
 		buf = msg->msg_iter.kvec->iov_base;
@@ -2133,12 +2034,9 @@ int smbd_recv(struct smbd_connection *info, struct msghdr *msg)
 		/* It's a bug in upper layer to get there */
 		cifs_dbg(VFS, "CIFS: invalid msg type %d\n",
 			msg->msg_iter.type);
-		rc = -EIO;
+		rc = -EINVAL;
 	}
 
-	info->smbd_recv_pending--;
-	wake_up(&info->wait_smbd_recv_pending);
-
 	/* SMBDirect will read it all or nothing */
 	if (rc > 0)
 		msg->msg_iter.count = 0;
@@ -2163,7 +2061,6 @@ int smbd_send(struct smbd_connection *info, struct smb_rqst *rqst)
 	struct kvec *iov;
 	int rc;
 
-	info->smbd_send_pending++;
 	if (info->transport_status != SMBD_CONNECTED) {
 		rc = -ENODEV;
 		goto done;
@@ -2319,9 +2216,6 @@ int smbd_send(struct smbd_connection *info, struct smb_rqst *rqst)
 	wait_event(info->wait_send_payload_pending,
 		atomic_read(&info->send_payload_pending) == 0);
 
-	info->smbd_send_pending--;
-	wake_up(&info->wait_smbd_send_pending);
-
 	return rc;
 }
 
diff --git a/fs/cifs/smbdirect.h b/fs/cifs/smbdirect.h
index 7849989..4563c0c 100644
--- a/fs/cifs/smbdirect.h
+++ b/fs/cifs/smbdirect.h
@@ -70,13 +70,11 @@ struct smbd_connection {
 	int ri_rc;
 	struct completion ri_done;
 	wait_queue_head_t conn_wait;
-	wait_queue_head_t wait_destroy;
 	wait_queue_head_t disconn_wait;
 
 	struct completion negotiate_completion;
 	bool negotiate_done;
 
-	struct work_struct destroy_work;
 	struct work_struct disconnect_work;
 	struct work_struct recv_done_work;
 	struct work_struct post_send_credits_work;
@@ -124,13 +122,6 @@ struct smbd_connection {
 	wait_queue_head_t wait_for_mr_cleanup;
 
 	/* Activity accoutning */
-	/* Pending reqeusts issued from upper layer */
-	int smbd_send_pending;
-	wait_queue_head_t wait_smbd_send_pending;
-
-	int smbd_recv_pending;
-	wait_queue_head_t wait_smbd_recv_pending;
-
 	atomic_t send_pending;
 	wait_queue_head_t wait_send_pending;
 	atomic_t send_payload_pending;
-- 
2.7.4