1 files changed, 293 insertions, 0 deletions

diff --git a/net/rds/rdma_transport.c b/net/rds/rdma_transport.c
new file mode 100644
index 000000000..6b0f57c83
--- /dev/null
+++ b/net/rds/rdma_transport.c
@@ -0,0 +1,293 @@
+/*
+ * Copyright (c) 2009, 2018 Oracle and/or its affiliates. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer.
+ *
+ *      - Redistributions in binary form must reproduce the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer in the documentation and/or other materials
+ *        provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ */
+#include <linux/module.h>
+#include <rdma/rdma_cm.h>
+
+#include "rds_single_path.h"
+#include "rdma_transport.h"
+#include "ib.h"
+
+/* Global IPv4 and IPv6 RDS RDMA listener cm_id */
+static struct rdma_cm_id *rds_rdma_listen_id;
+#if IS_ENABLED(CONFIG_IPV6)
+static struct rdma_cm_id *rds6_rdma_listen_id;
+#endif
+
+static int rds_rdma_cm_event_handler_cmn(struct rdma_cm_id *cm_id,
+					 struct rdma_cm_event *event,
+					 bool isv6)
+{
+	/* this can be null in the listening path */
+	struct rds_connection *conn = cm_id->context;
+	struct rds_transport *trans;
+	int ret = 0;
+
+	rdsdebug("conn %p id %p handling event %u (%s)\n", conn, cm_id,
+		 event->event, rdma_event_msg(event->event));
+
+	if (cm_id->device->node_type == RDMA_NODE_IB_CA)
+		trans = &rds_ib_transport;
+
+	/* Prevent shutdown from tearing down the connection
+	 * while we're executing. */
+	if (conn) {
+		mutex_lock(&conn->c_cm_lock);
+
+		/* If the connection is being shut down, bail out
+		 * right away. We return 0 so cm_id doesn't get
+		 * destroyed prematurely */
+		if (rds_conn_state(conn) == RDS_CONN_DISCONNECTING) {
+			/* Reject incoming connections while we're tearing
+			 * down an existing one. */
+			if (event->event == RDMA_CM_EVENT_CONNECT_REQUEST)
+				ret = 1;
+			goto out;
+		}
+	}
+
+	switch (event->event) {
+	case RDMA_CM_EVENT_CONNECT_REQUEST:
+		ret = trans->cm_handle_connect(cm_id, event, isv6);
+		break;
+
+	case RDMA_CM_EVENT_ADDR_RESOLVED:
+		/* XXX do we need to clean up if this fails? */
+		ret = rdma_resolve_route(cm_id,
+					 RDS_RDMA_RESOLVE_TIMEOUT_MS);
+		break;
+
+	case RDMA_CM_EVENT_ROUTE_RESOLVED:
+		/* Connection could have been dropped so make sure the
+		 * cm_id is valid before proceeding
+		 */
+		if (conn) {
+			struct rds_ib_connection *ibic;
+
+			ibic = conn->c_transport_data;
+			if (ibic && ibic->i_cm_id == cm_id)
+				ret = trans->cm_initiate_connect(cm_id, isv6);
+			else
+				rds_conn_drop(conn);
+		}
+		break;
+
+	case RDMA_CM_EVENT_ESTABLISHED:
+		trans->cm_connect_complete(conn, event);
+		break;
+
+	case RDMA_CM_EVENT_REJECTED:
+		rdsdebug("Connection rejected: %s\n",
+			 rdma_reject_msg(cm_id, event->status));
+		/* FALLTHROUGH */
+	case RDMA_CM_EVENT_ADDR_ERROR:
+	case RDMA_CM_EVENT_ROUTE_ERROR:
+	case RDMA_CM_EVENT_CONNECT_ERROR:
+	case RDMA_CM_EVENT_UNREACHABLE:
+	case RDMA_CM_EVENT_DEVICE_REMOVAL:
+	case RDMA_CM_EVENT_ADDR_CHANGE:
+		if (conn)
+			rds_conn_drop(conn);
+		break;
+
+	case RDMA_CM_EVENT_DISCONNECTED:
+		rdsdebug("DISCONNECT event - dropping connection "
+			 "%pI6c->%pI6c\n", &conn->c_laddr,
+			 &conn->c_faddr);
+		rds_conn_drop(conn);
+		break;
+
+	case RDMA_CM_EVENT_TIMEWAIT_EXIT:
+		if (conn) {
+			pr_info("RDS: RDMA_CM_EVENT_TIMEWAIT_EXIT event: dropping connection %pI6c->%pI6c\n",
+				&conn->c_laddr, &conn->c_faddr);
+			rds_conn_drop(conn);
+		}
+		break;
+
+	default:
+		/* things like device disconnect? */
+		printk(KERN_ERR "RDS: unknown event %u (%s)!\n",
+		       event->event, rdma_event_msg(event->event));
+		break;
+	}
+
+out:
+	if (conn)
+		mutex_unlock(&conn->c_cm_lock);
+
+	rdsdebug("id %p event %u (%s) handling ret %d\n", cm_id, event->event,
+		 rdma_event_msg(event->event), ret);
+
+	return ret;
+}
+
+int rds_rdma_cm_event_handler(struct rdma_cm_id *cm_id,
+			      struct rdma_cm_event *event)
+{
+	return rds_rdma_cm_event_handler_cmn(cm_id, event, false);
+}
+
+#if IS_ENABLED(CONFIG_IPV6)
+int rds6_rdma_cm_event_handler(struct rdma_cm_id *cm_id,
+			       struct rdma_cm_event *event)
+{
+	return rds_rdma_cm_event_handler_cmn(cm_id, event, true);
+}
+#endif
+
+static int rds_rdma_listen_init_common(rdma_cm_event_handler handler,
+				       struct sockaddr *sa,
+				       struct rdma_cm_id **ret_cm_id)
+{
+	struct rdma_cm_id *cm_id;
+	int ret;
+
+	cm_id = rdma_create_id(&init_net, handler, NULL,
+			       RDMA_PS_TCP, IB_QPT_RC);
+	if (IS_ERR(cm_id)) {
+		ret = PTR_ERR(cm_id);
+		printk(KERN_ERR "RDS/RDMA: failed to setup listener, "
+		       "rdma_create_id() returned %d\n", ret);
+		return ret;
+	}
+
+	/*
+	 * XXX I bet this binds the cm_id to a device.  If we want to support
+	 * fail-over we'll have to take this into consideration.
+	 */
+	ret = rdma_bind_addr(cm_id, sa);
+	if (ret) {
+		printk(KERN_ERR "RDS/RDMA: failed to setup listener, "
+		       "rdma_bind_addr() returned %d\n", ret);
+		goto out;
+	}
+
+	ret = rdma_listen(cm_id, 128);
+	if (ret) {
+		printk(KERN_ERR "RDS/RDMA: failed to setup listener, "
+		       "rdma_listen() returned %d\n", ret);
+		goto out;
+	}
+
+	rdsdebug("cm %p listening on port %u\n", cm_id, RDS_PORT);
+
+	*ret_cm_id = cm_id;
+	cm_id = NULL;
+out:
+	if (cm_id)
+		rdma_destroy_id(cm_id);
+	return ret;
+}
+
+/* Initialize the RDS RDMA listeners.  We create two listeners for
+ * compatibility reason.  The one on RDS_PORT is used for IPv4
+ * requests only.  The one on RDS_CM_PORT is used for IPv6 requests
+ * only.  So only IPv6 enabled RDS module will communicate using this
+ * port.
+ */
+static int rds_rdma_listen_init(void)
+{
+	int ret;
+#if IS_ENABLED(CONFIG_IPV6)
+	struct sockaddr_in6 sin6;
+#endif
+	struct sockaddr_in sin;
+
+	sin.sin_family = PF_INET;
+	sin.sin_addr.s_addr = htonl(INADDR_ANY);
+	sin.sin_port = htons(RDS_PORT);
+	ret = rds_rdma_listen_init_common(rds_rdma_cm_event_handler,
+					  (struct sockaddr *)&sin,
+					  &rds_rdma_listen_id);
+	if (ret != 0)
+		return ret;
+
+#if IS_ENABLED(CONFIG_IPV6)
+	sin6.sin6_family = PF_INET6;
+	sin6.sin6_addr = in6addr_any;
+	sin6.sin6_port = htons(RDS_CM_PORT);
+	sin6.sin6_scope_id = 0;
+	sin6.sin6_flowinfo = 0;
+	ret = rds_rdma_listen_init_common(rds6_rdma_cm_event_handler,
+					  (struct sockaddr *)&sin6,
+					  &rds6_rdma_listen_id);
+	/* Keep going even when IPv6 is not enabled in the system. */
+	if (ret != 0)
+		rdsdebug("Cannot set up IPv6 RDMA listener\n");
+#endif
+	return 0;
+}
+
+static void rds_rdma_listen_stop(void)
+{
+	if (rds_rdma_listen_id) {
+		rdsdebug("cm %p\n", rds_rdma_listen_id);
+		rdma_destroy_id(rds_rdma_listen_id);
+		rds_rdma_listen_id = NULL;
+	}
+#if IS_ENABLED(CONFIG_IPV6)
+	if (rds6_rdma_listen_id) {
+		rdsdebug("cm %p\n", rds6_rdma_listen_id);
+		rdma_destroy_id(rds6_rdma_listen_id);
+		rds6_rdma_listen_id = NULL;
+	}
+#endif
+}
+
+static int rds_rdma_init(void)
+{
+	int ret;
+
+	ret = rds_ib_init();
+	if (ret)
+		goto out;
+
+	ret = rds_rdma_listen_init();
+	if (ret)
+		rds_ib_exit();
+out:
+	return ret;
+}
+module_init(rds_rdma_init);
+
+static void rds_rdma_exit(void)
+{
+	/* stop listening first to ensure no new connections are attempted */
+	rds_rdma_listen_stop();
+	rds_ib_exit();
+}
+module_exit(rds_rdma_exit);
+
+MODULE_AUTHOR("Oracle Corporation <rds-devel@oss.oracle.com>");
+MODULE_DESCRIPTION("RDS: IB transport");
+MODULE_LICENSE("Dual BSD/GPL");