IB: IP address based RDMA connection manager

Kernel connection management agent over InfiniBand that connects based
on IP addresses.  The agent defines a generic RDMA connection
abstraction to support clients wanting to connect over different RDMA
devices.

The agent also handles RDMA device hotplug events on behalf of clients.

Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

2 files changed, 1931 insertions, 2 deletions

diff --git a/drivers/infiniband/core/Makefile b/drivers/infiniband/core/Makefile
index 05095919d16..68e73ec2d1f 100644
--- a/drivers/infiniband/core/Makefile
+++ b/drivers/infiniband/core/Makefile
@@ -1,7 +1,7 @@
-addr_trans-$(CONFIG_INFINIBAND_ADDR_TRANS) := ib_addr.o
+infiniband-$(CONFIG_INFINIBAND_ADDR_TRANS)	:= ib_addr.o rdma_cm.o
 
 obj-$(CONFIG_INFINIBAND) +=		ib_core.o ib_mad.o ib_sa.o \
-					ib_cm.o $(addr_trans-y)
+					ib_cm.o $(infiniband-y)
 obj-$(CONFIG_INFINIBAND_USER_MAD) +=	ib_umad.o
 obj-$(CONFIG_INFINIBAND_USER_ACCESS) +=	ib_uverbs.o ib_ucm.o
 
@@ -14,6 +14,8 @@ ib_sa-y :=			sa_query.o
 
 ib_cm-y :=			cm.o
 
+rdma_cm-y :=			cma.o
+
 ib_addr-y :=			addr.o
 
 ib_umad-y :=			user_mad.o
diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
new file mode 100644
index 00000000000..a76834edf60
--- /dev/null
+++ b/drivers/infiniband/core/cma.c
@@ -0,0 +1,1927 @@
+/*
+ * Copyright (c) 2005 Voltaire Inc.  All rights reserved.
+ * Copyright (c) 2002-2005, Network Appliance, Inc. All rights reserved.
+ * Copyright (c) 1999-2005, Mellanox Technologies, Inc. All rights reserved.
+ * Copyright (c) 2005-2006 Intel Corporation.  All rights reserved.
+ *
+ * This Software is licensed under one of the following licenses:
+ *
+ * 1) under the terms of the "Common Public License 1.0" a copy of which is
+ *    available from the Open Source Initiative, see
+ *    http://www.opensource.org/licenses/cpl.php.
+ *
+ * 2) under the terms of the "The BSD License" a copy of which is
+ *    available from the Open Source Initiative, see
+ *    http://www.opensource.org/licenses/bsd-license.php.
+ *
+ * 3) under the terms of the "GNU General Public License (GPL) Version 2" a
+ *    copy of which is available from the Open Source Initiative, see
+ *    http://www.opensource.org/licenses/gpl-license.php.
+ *
+ * Licensee has the right to choose one of the above licenses.
+ *
+ * Redistributions of source code must retain the above copyright
+ * notice and one of the license notices.
+ *
+ * Redistributions in binary form must reproduce both the above copyright
+ * notice, one of the license notices in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ */
+
+#include <linux/completion.h>
+#include <linux/in.h>
+#include <linux/in6.h>
+#include <linux/mutex.h>
+#include <linux/random.h>
+#include <linux/idr.h>
+
+#include <net/tcp.h>
+
+#include <rdma/rdma_cm.h>
+#include <rdma/rdma_cm_ib.h>
+#include <rdma/ib_cache.h>
+#include <rdma/ib_cm.h>
+#include <rdma/ib_sa.h>
+
+MODULE_AUTHOR("Sean Hefty");
+MODULE_DESCRIPTION("Generic RDMA CM Agent");
+MODULE_LICENSE("Dual BSD/GPL");
+
+#define CMA_CM_RESPONSE_TIMEOUT 20
+#define CMA_MAX_CM_RETRIES 3
+
+static void cma_add_one(struct ib_device *device);
+static void cma_remove_one(struct ib_device *device);
+
+static struct ib_client cma_client = {
+	.name   = "cma",
+	.add    = cma_add_one,
+	.remove = cma_remove_one
+};
+
+static LIST_HEAD(dev_list);
+static LIST_HEAD(listen_any_list);
+static DEFINE_MUTEX(lock);
+static struct workqueue_struct *cma_wq;
+static DEFINE_IDR(sdp_ps);
+static DEFINE_IDR(tcp_ps);
+
+struct cma_device {
+	struct list_head	list;
+	struct ib_device	*device;
+	__be64			node_guid;
+	struct completion	comp;
+	atomic_t		refcount;
+	struct list_head	id_list;
+};
+
+enum cma_state {
+	CMA_IDLE,
+	CMA_ADDR_QUERY,
+	CMA_ADDR_RESOLVED,
+	CMA_ROUTE_QUERY,
+	CMA_ROUTE_RESOLVED,
+	CMA_CONNECT,
+	CMA_DISCONNECT,
+	CMA_ADDR_BOUND,
+	CMA_LISTEN,
+	CMA_DEVICE_REMOVAL,
+	CMA_DESTROYING
+};
+
+struct rdma_bind_list {
+	struct idr		*ps;
+	struct hlist_head	owners;
+	unsigned short		port;
+};
+
+/*
+ * Device removal can occur at anytime, so we need extra handling to
+ * serialize notifying the user of device removal with other callbacks.
+ * We do this by disabling removal notification while a callback is in process,
+ * and reporting it after the callback completes.
+ */
+struct rdma_id_private {
+	struct rdma_cm_id	id;
+
+	struct rdma_bind_list	*bind_list;
+	struct hlist_node	node;
+	struct list_head	list;
+	struct list_head	listen_list;
+	struct cma_device	*cma_dev;
+
+	enum cma_state		state;
+	spinlock_t		lock;
+	struct completion	comp;
+	atomic_t		refcount;
+	wait_queue_head_t	wait_remove;
+	atomic_t		dev_remove;
+
+	int			backlog;
+	int			timeout_ms;
+	struct ib_sa_query	*query;
+	int			query_id;
+	union {
+		struct ib_cm_id	*ib;
+	} cm_id;
+
+	u32			seq_num;
+	u32			qp_num;
+	enum ib_qp_type		qp_type;
+	u8			srq;
+};
+
+struct cma_work {
+	struct work_struct	work;
+	struct rdma_id_private	*id;
+	enum cma_state		old_state;
+	enum cma_state		new_state;
+	struct rdma_cm_event	event;
+};
+
+union cma_ip_addr {
+	struct in6_addr ip6;
+	struct {
+		__u32 pad[3];
+		__u32 addr;
+	} ip4;
+};
+
+struct cma_hdr {
+	u8 cma_version;
+	u8 ip_version;	/* IP version: 7:4 */
+	__u16 port;
+	union cma_ip_addr src_addr;
+	union cma_ip_addr dst_addr;
+};
+
+struct sdp_hh {
+	u8 bsdh[16];
+	u8 sdp_version; /* Major version: 7:4 */
+	u8 ip_version;	/* IP version: 7:4 */
+	u8 sdp_specific1[10];
+	__u16 port;
+	__u16 sdp_specific2;
+	union cma_ip_addr src_addr;
+	union cma_ip_addr dst_addr;
+};
+
+struct sdp_hah {
+	u8 bsdh[16];
+	u8 sdp_version;
+};
+
+#define CMA_VERSION 0x00
+#define SDP_MAJ_VERSION 0x2
+
+static int cma_comp(struct rdma_id_private *id_priv, enum cma_state comp)
+{
+	unsigned long flags;
+	int ret;
+
+	spin_lock_irqsave(&id_priv->lock, flags);
+	ret = (id_priv->state == comp);
+	spin_unlock_irqrestore(&id_priv->lock, flags);
+	return ret;
+}
+
+static int cma_comp_exch(struct rdma_id_private *id_priv,
+			 enum cma_state comp, enum cma_state exch)
+{
+	unsigned long flags;
+	int ret;
+
+	spin_lock_irqsave(&id_priv->lock, flags);
+	if ((ret = (id_priv->state == comp)))
+		id_priv->state = exch;
+	spin_unlock_irqrestore(&id_priv->lock, flags);
+	return ret;
+}
+
+static enum cma_state cma_exch(struct rdma_id_private *id_priv,
+			       enum cma_state exch)
+{
+	unsigned long flags;
+	enum cma_state old;
+
+	spin_lock_irqsave(&id_priv->lock, flags);
+	old = id_priv->state;
+	id_priv->state = exch;
+	spin_unlock_irqrestore(&id_priv->lock, flags);
+	return old;
+}
+
+static inline u8 cma_get_ip_ver(struct cma_hdr *hdr)
+{
+	return hdr->ip_version >> 4;
+}
+
+static inline void cma_set_ip_ver(struct cma_hdr *hdr, u8 ip_ver)
+{
+	hdr->ip_version = (ip_ver << 4) | (hdr->ip_version & 0xF);
+}
+
+static inline u8 sdp_get_majv(u8 sdp_version)
+{
+	return sdp_version >> 4;
+}
+
+static inline u8 sdp_get_ip_ver(struct sdp_hh *hh)
+{
+	return hh->ip_version >> 4;
+}
+
+static inline void sdp_set_ip_ver(struct sdp_hh *hh, u8 ip_ver)
+{
+	hh->ip_version = (ip_ver << 4) | (hh->ip_version & 0xF);
+}
+
+static void cma_attach_to_dev(struct rdma_id_private *id_priv,
+			      struct cma_device *cma_dev)
+{
+	atomic_inc(&cma_dev->refcount);
+	id_priv->cma_dev = cma_dev;
+	id_priv->id.device = cma_dev->device;
+	list_add_tail(&id_priv->list, &cma_dev->id_list);
+}
+
+static inline void cma_deref_dev(struct cma_device *cma_dev)
+{
+	if (atomic_dec_and_test(&cma_dev->refcount))
+		complete(&cma_dev->comp);
+}
+
+static void cma_detach_from_dev(struct rdma_id_private *id_priv)
+{
+	list_del(&id_priv->list);
+	cma_deref_dev(id_priv->cma_dev);
+	id_priv->cma_dev = NULL;
+}
+
+static int cma_acquire_ib_dev(struct rdma_id_private *id_priv)
+{
+	struct cma_device *cma_dev;
+	union ib_gid *gid;
+	int ret = -ENODEV;
+
+	gid = ib_addr_get_sgid(&id_priv->id.route.addr.dev_addr);
+
+	mutex_lock(&lock);
+	list_for_each_entry(cma_dev, &dev_list, list) {
+		ret = ib_find_cached_gid(cma_dev->device, gid,
+					 &id_priv->id.port_num, NULL);
+		if (!ret) {
+			cma_attach_to_dev(id_priv, cma_dev);
+			break;
+		}
+	}
+	mutex_unlock(&lock);
+	return ret;
+}
+
+static int cma_acquire_dev(struct rdma_id_private *id_priv)
+{
+	switch (id_priv->id.route.addr.dev_addr.dev_type) {
+	case IB_NODE_CA:
+		return cma_acquire_ib_dev(id_priv);
+	default:
+		return -ENODEV;
+	}
+}
+
+static void cma_deref_id(struct rdma_id_private *id_priv)
+{
+	if (atomic_dec_and_test(&id_priv->refcount))
+		complete(&id_priv->comp);
+}
+
+static void cma_release_remove(struct rdma_id_private *id_priv)
+{
+	if (atomic_dec_and_test(&id_priv->dev_remove))
+		wake_up(&id_priv->wait_remove);
+}
+
+struct rdma_cm_id *rdma_create_id(rdma_cm_event_handler event_handler,
+				  void *context, enum rdma_port_space ps)
+{
+	struct rdma_id_private *id_priv;
+
+	id_priv = kzalloc(sizeof *id_priv, GFP_KERNEL);
+	if (!id_priv)
+		return ERR_PTR(-ENOMEM);
+
+	id_priv->state = CMA_IDLE;
+	id_priv->id.context = context;
+	id_priv->id.event_handler = event_handler;
+	id_priv->id.ps = ps;
+	spin_lock_init(&id_priv->lock);
+	init_completion(&id_priv->comp);
+	atomic_set(&id_priv->refcount, 1);
+	init_waitqueue_head(&id_priv->wait_remove);
+	atomic_set(&id_priv->dev_remove, 0);
+	INIT_LIST_HEAD(&id_priv->listen_list);
+	get_random_bytes(&id_priv->seq_num, sizeof id_priv->seq_num);
+
+	return &id_priv->id;
+}
+EXPORT_SYMBOL(rdma_create_id);
+
+static int cma_init_ib_qp(struct rdma_id_private *id_priv, struct ib_qp *qp)
+{
+	struct ib_qp_attr qp_attr;
+	struct rdma_dev_addr *dev_addr;
+	int ret;
+
+	dev_addr = &id_priv->id.route.addr.dev_addr;
+	ret = ib_find_cached_pkey(id_priv->id.device, id_priv->id.port_num,
+				  ib_addr_get_pkey(dev_addr),
+				  &qp_attr.pkey_index);
+	if (ret)
+		return ret;
+
+	qp_attr.qp_state = IB_QPS_INIT;
+	qp_attr.qp_access_flags = IB_ACCESS_LOCAL_WRITE;
+	qp_attr.port_num = id_priv->id.port_num;
+	return ib_modify_qp(qp, &qp_attr, IB_QP_STATE | IB_QP_ACCESS_FLAGS |
+					  IB_QP_PKEY_INDEX | IB_QP_PORT);
+}
+
+int rdma_create_qp(struct rdma_cm_id *id, struct ib_pd *pd,
+		   struct ib_qp_init_attr *qp_init_attr)
+{
+	struct rdma_id_private *id_priv;
+	struct ib_qp *qp;
+	int ret;
+
+	id_priv = container_of(id, struct rdma_id_private, id);
+	if (id->device != pd->device)
+		return -EINVAL;
+
+	qp = ib_create_qp(pd, qp_init_attr);
+	if (IS_ERR(qp))
+		return PTR_ERR(qp);
+
+	switch (id->device->node_type) {
+	case IB_NODE_CA:
+		ret = cma_init_ib_qp(id_priv, qp);
+		break;
+	default:
+		ret = -ENOSYS;
+		break;
+	}
+
+	if (ret)
+		goto err;
+
+	id->qp = qp;
+	id_priv->qp_num = qp->qp_num;
+	id_priv->qp_type = qp->qp_type;
+	id_priv->srq = (qp->srq != NULL);
+	return 0;
+err:
+	ib_destroy_qp(qp);
+	return ret;
+}
+EXPORT_SYMBOL(rdma_create_qp);
+
+void rdma_destroy_qp(struct rdma_cm_id *id)
+{
+	ib_destroy_qp(id->qp);
+}
+EXPORT_SYMBOL(rdma_destroy_qp);
+
+static int cma_modify_qp_rtr(struct rdma_cm_id *id)
+{
+	struct ib_qp_attr qp_attr;
+	int qp_attr_mask, ret;
+
+	if (!id->qp)
+		return 0;
+
+	/* Need to update QP attributes from default values. */
+	qp_attr.qp_state = IB_QPS_INIT;
+	ret = rdma_init_qp_attr(id, &qp_attr, &qp_attr_mask);
+	if (ret)
+		return ret;
+
+	ret = ib_modify_qp(id->qp, &qp_attr, qp_attr_mask);
+	if (ret)
+		return ret;
+
+	qp_attr.qp_state = IB_QPS_RTR;
+	ret = rdma_init_qp_attr(id, &qp_attr, &qp_attr_mask);
+	if (ret)
+		return ret;
+
+	return ib_modify_qp(id->qp, &qp_attr, qp_attr_mask);
+}
+
+static int cma_modify_qp_rts(struct rdma_cm_id *id)
+{
+	struct ib_qp_attr qp_attr;
+	int qp_attr_mask, ret;
+
+	if (!id->qp)
+		return 0;
+
+	qp_attr.qp_state = IB_QPS_RTS;
+	ret = rdma_init_qp_attr(id, &qp_attr, &qp_attr_mask);
+	if (ret)
+		return ret;
+
+	return ib_modify_qp(id->qp, &qp_attr, qp_attr_mask);
+}
+
+static int cma_modify_qp_err(struct rdma_cm_id *id)
+{
+	struct ib_qp_attr qp_attr;
+
+	if (!id->qp)
+		return 0;
+
+	qp_attr.qp_state = IB_QPS_ERR;
+	return ib_modify_qp(id->qp, &qp_attr, IB_QP_STATE);
+}
+
+int rdma_init_qp_attr(struct rdma_cm_id *id, struct ib_qp_attr *qp_attr,
+		       int *qp_attr_mask)
+{
+	struct rdma_id_private *id_priv;
+	int ret;
+
+	id_priv = container_of(id, struct rdma_id_private, id);
+	switch (id_priv->id.device->node_type) {
+	case IB_NODE_CA:
+		ret = ib_cm_init_qp_attr(id_priv->cm_id.ib, qp_attr,
+					 qp_attr_mask);
+		if (qp_attr->qp_state == IB_QPS_RTR)
+			qp_attr->rq_psn = id_priv->seq_num;
+		break;
+	default:
+		ret = -ENOSYS;
+		break;
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL(rdma_init_qp_attr);
+
+static inline int cma_zero_addr(struct sockaddr *addr)
+{
+	struct in6_addr *ip6;
+
+	if (addr->sa_family == AF_INET)
+		return ZERONET(((struct sockaddr_in *) addr)->sin_addr.s_addr);
+	else {
+		ip6 = &((struct sockaddr_in6 *) addr)->sin6_addr;
+		return (ip6->s6_addr32[0] | ip6->s6_addr32[1] |
+			ip6->s6_addr32[3] | ip6->s6_addr32[4]) == 0;
+	}
+}
+
+static inline int cma_loopback_addr(struct sockaddr *addr)
+{
+	return LOOPBACK(((struct sockaddr_in *) addr)->sin_addr.s_addr);
+}
+
+static inline int cma_any_addr(struct sockaddr *addr)
+{
+	return cma_zero_addr(addr) || cma_loopback_addr(addr);
+}
+
+static inline int cma_any_port(struct sockaddr *addr)
+{
+	return !((struct sockaddr_in *) addr)->sin_port;
+}
+
+static int cma_get_net_info(void *hdr, enum rdma_port_space ps,
+			    u8 *ip_ver, __u16 *port,
+			    union cma_ip_addr **src, union cma_ip_addr **dst)
+{
+	switch (ps) {
+	case RDMA_PS_SDP:
+		if (sdp_get_majv(((struct sdp_hh *) hdr)->sdp_version) !=
+		    SDP_MAJ_VERSION)
+			return -EINVAL;
+
+		*ip_ver	= sdp_get_ip_ver(hdr);
+		*port	= ((struct sdp_hh *) hdr)->port;
+		*src	= &((struct sdp_hh *) hdr)->src_addr;
+		*dst	= &((struct sdp_hh *) hdr)->dst_addr;
+		break;
+	default:
+		if (((struct cma_hdr *) hdr)->cma_version != CMA_VERSION)
+			return -EINVAL;
+
+		*ip_ver	= cma_get_ip_ver(hdr);
+		*port	= ((struct cma_hdr *) hdr)->port;
+		*src	= &((struct cma_hdr *) hdr)->src_addr;
+		*dst	= &((struct cma_hdr *) hdr)->dst_addr;
+		break;
+	}
+
+	if (*ip_ver != 4 && *ip_ver != 6)
+		return -EINVAL;
+	return 0;
+}
+
+static void cma_save_net_info(struct rdma_addr *addr,
+			      struct rdma_addr *listen_addr,
+			      u8 ip_ver, __u16 port,
+			      union cma_ip_addr *src, union cma_ip_addr *dst)
+{
+	struct sockaddr_in *listen4, *ip4;
+	struct sockaddr_in6 *listen6, *ip6;
+
+	switch (ip_ver) {
+	case 4:
+		listen4 = (struct sockaddr_in *) &listen_addr->src_addr;
+		ip4 = (struct sockaddr_in *) &addr->src_addr;
+		ip4->sin_family = listen4->sin_family;
+		ip4->sin_addr.s_addr = dst->ip4.addr;
+		ip4->sin_port = listen4->sin_port;
+
+		ip4 = (struct sockaddr_in *) &addr->dst_addr;
+		ip4->sin_family = listen4->sin_family;
+		ip4->sin_addr.s_addr = src->ip4.addr;
+		ip4->sin_port = port;
+		break;
+	case 6:
+		listen6 = (struct sockaddr_in6 *) &listen_addr->src_addr;
+		ip6 = (struct sockaddr_in6 *) &addr->src_addr;
+		ip6->sin6_family = listen6->sin6_family;
+		ip6->sin6_addr = dst->ip6;
+		ip6->sin6_port = listen6->sin6_port;
+
+		ip6 = (struct sockaddr_in6 *) &addr->dst_addr;
+		ip6->sin6_family = listen6->sin6_family;
+		ip6->sin6_addr = src->ip6;
+		ip6->sin6_port = port;
+		break;
+	default:
+		break;
+	}
+}
+
+static inline int cma_user_data_offset(enum rdma_port_space ps)
+{
+	switch (ps) {
+	case RDMA_PS_SDP:
+		return 0;
+	default:
+		return sizeof(struct cma_hdr);
+	}
+}
+
+static int cma_notify_user(struct rdma_id_private *id_priv,
+			   enum rdma_cm_event_type type, int status,
+			   void *data, u8 data_len)
+{
+	struct rdma_cm_event event;
+
+	event.event = type;
+	event.status = status;
+	event.private_data = data;
+	event.private_data_len = data_len;
+
+	return id_priv->id.event_handler(&id_priv->id, &event);
+}
+
+static void cma_cancel_route(struct rdma_id_private *id_priv)
+{
+	switch (id_priv->id.device->node_type) {
+	case IB_NODE_CA:
+		if (id_priv->query)
+			ib_sa_cancel_query(id_priv->query_id, id_priv->query);
+		break;
+	default:
+		break;
+	}
+}
+
+static inline int cma_internal_listen(struct rdma_id_private *id_priv)
+{
+	return (id_priv->state == CMA_LISTEN) && id_priv->cma_dev &&
+	       cma_any_addr(&id_priv->id.route.addr.src_addr);
+}
+
+static void cma_destroy_listen(struct rdma_id_private *id_priv)
+{
+	cma_exch(id_priv, CMA_DESTROYING);
+
+	if (id_priv->cma_dev) {
+		switch (id_priv->id.device->node_type) {
+		case IB_NODE_CA:
+	 		if (id_priv->cm_id.ib && !IS_ERR(id_priv->cm_id.ib))
+				ib_destroy_cm_id(id_priv->cm_id.ib);
+			break;
+		default:
+			break;
+		}
+		cma_detach_from_dev(id_priv);
+	}
+	list_del(&id_priv->listen_list);
+
+	cma_deref_id(id_priv);
+	wait_for_completion(&id_priv->comp);
+
+	kfree(id_priv);
+}
+
+static void cma_cancel_listens(struct rdma_id_private *id_priv)
+{
+	struct rdma_id_private *dev_id_priv;
+
+	mutex_lock(&lock);
+	list_del(&id_priv->list);
+
+	while (!list_empty(&id_priv->listen_list)) {
+		dev_id_priv = list_entry(id_priv->listen_list.next,
+					 struct rdma_id_private, listen_list);
+		cma_destroy_listen(dev_id_priv);
+	}
+	mutex_unlock(&lock);
+}
+
+static void cma_cancel_operation(struct rdma_id_private *id_priv,
+				 enum cma_state state)
+{
+	switch (state) {
+	case CMA_ADDR_QUERY:
+		rdma_addr_cancel(&id_priv->id.route.addr.dev_addr);
+		break;
+	case CMA_ROUTE_QUERY:
+		cma_cancel_route(id_priv);
+		break;
+	case CMA_LISTEN:
+		if (cma_any_addr(&id_priv->id.route.addr.src_addr) &&
+		    !id_priv->cma_dev)
+			cma_cancel_listens(id_priv);
+		break;
+	default:
+		break;
+	}
+}
+
+static void cma_release_port(struct rdma_id_private *id_priv)
+{
+	struct rdma_bind_list *bind_list = id_priv->bind_list;
+
+	if (!bind_list)
+		return;
+
+	mutex_lock(&lock);
+	hlist_del(&id_priv->node);
+	if (hlist_empty(&bind_list->owners)) {
+		idr_remove(bind_list->ps, bind_list->port);
+		kfree(bind_list);
+	}
+	mutex_unlock(&lock);
+}
+
+void rdma_destroy_id(struct rdma_cm_id *id)
+{
+	struct rdma_id_private *id_priv;
+	enum cma_state state;
+
+	id_priv = container_of(id, struct rdma_id_private, id);
+	state = cma_exch(id_priv, CMA_DESTROYING);
+	cma_cancel_operation(id_priv, state);
+
+	if (id_priv->cma_dev) {
+		switch (id->device->node_type) {
+		case IB_NODE_CA:
+	 		if (id_priv->cm_id.ib && !IS_ERR(id_priv->cm_id.ib))
+				ib_destroy_cm_id(id_priv->cm_id.ib);
+			break;
+		default:
+			break;
+		}
+	  	mutex_lock(&lock);
+		cma_detach_from_dev(id_priv);
+		mutex_unlock(&lock);
+	}
+
+	cma_release_port(id_priv);
+	cma_deref_id(id_priv);
+	wait_for_completion(&id_priv->comp);
+
+	kfree(id_priv->id.route.path_rec);
+	kfree(id_priv);
+}
+EXPORT_SYMBOL(rdma_destroy_id);
+
+static int cma_rep_recv(struct rdma_id_private *id_priv)
+{
+	int ret;
+
+	ret = cma_modify_qp_rtr(&id_priv->id);
+	if (ret)
+		goto reject;
+
+	ret = cma_modify_qp_rts(&id_priv->id);
+	if (ret)
+		goto reject;
+
+	ret = ib_send_cm_rtu(id_priv->cm_id.ib, NULL, 0);
+	if (ret)
+		goto reject;
+
+	return 0;
+reject:
+	cma_modify_qp_err(&id_priv->id);
+	ib_send_cm_rej(id_priv->cm_id.ib, IB_CM_REJ_CONSUMER_DEFINED,
+		       NULL, 0, NULL, 0);
+	return ret;
+}
+
+static int cma_verify_rep(struct rdma_id_private *id_priv, void *data)
+{
+	if (id_priv->id.ps == RDMA_PS_SDP &&
+	    sdp_get_majv(((struct sdp_hah *) data)->sdp_version) !=
+	    SDP_MAJ_VERSION)
+		return -EINVAL;
+
+	return 0;
+}
+
+static int cma_rtu_recv(struct rdma_id_private *id_priv)
+{
+	int ret;
+
+	ret = cma_modify_qp_rts(&id_priv->id);
+	if (ret)
+		goto reject;
+
+	return 0;
+reject:
+	cma_modify_qp_err(&id_priv->id);
+	ib_send_cm_rej(id_priv->cm_id.ib, IB_CM_REJ_CONSUMER_DEFINED,
+		       NULL, 0, NULL, 0);
+	return ret;
+}
+
+static int cma_ib_handler(struct ib_cm_id *cm_id, struct ib_cm_event *ib_event)
+{
+	struct rdma_id_private *id_priv = cm_id->context;
+	enum rdma_cm_event_type event;
+	u8 private_data_len = 0;
+	int ret = 0, status = 0;
+
+	atomic_inc(&id_priv->dev_remove);
+	if (!cma_comp(id_priv, CMA_CONNECT))
+		goto out;
+
+	switch (ib_event->event) {
+	case IB_CM_REQ_ERROR:
+	case IB_CM_REP_ERROR:
+		event = RDMA_CM_EVENT_UNREACHABLE;
+		status = -ETIMEDOUT;
+		break;
+	case IB_CM_REP_RECEIVED:
+		status = cma_verify_rep(id_priv, ib_event->private_data);
+		if (status)
+			event = RDMA_CM_EVENT_CONNECT_ERROR;
+		else if (id_priv->id.qp && id_priv->id.ps != RDMA_PS_SDP) {
+			status = cma_rep_recv(id_priv);
+			event = status ? RDMA_CM_EVENT_CONNECT_ERROR :
+					 RDMA_CM_EVENT_ESTABLISHED;
+		} else
+			event = RDMA_CM_EVENT_CONNECT_RESPONSE;
+		private_data_len = IB_CM_REP_PRIVATE_DATA_SIZE;
+		break;
+	case IB_CM_RTU_RECEIVED:
+		status = cma_rtu_recv(id_priv);
+		event = status ? RDMA_CM_EVENT_CONNECT_ERROR :
+				 RDMA_CM_EVENT_ESTABLISHED;
+		break;
+	case IB_CM_DREQ_ERROR:
+		status = -ETIMEDOUT; /* fall through */
+	case IB_CM_DREQ_RECEIVED:
+	case IB_CM_DREP_RECEIVED:
+		if (!cma_comp_exch(id_priv, CMA_CONNECT, CMA_DISCONNECT))
+			goto out;
+		event = RDMA_CM_EVENT_DISCONNECTED;
+		break;
+	case IB_CM_TIMEWAIT_EXIT:
+	case IB_CM_MRA_RECEIVED:
+		/* ignore event */
+		goto out;
+	case IB_CM_REJ_RECEIVED:
+		cma_modify_qp_err(&id_priv->id);
+		status = ib_event->param.rej_rcvd.reason;
+		event = RDMA_CM_EVENT_REJECTED;
+		break;
+	default:
+		printk(KERN_ERR "RDMA CMA: unexpected IB CM event: %d",
+		       ib_event->event);
+		goto out;
+	}
+
+	ret = cma_notify_user(id_priv, event, status, ib_event->private_data,
+			      private_data_len);
+	if (ret) {
+		/* Destroy the CM ID by returning a non-zero value. */
+		id_priv->cm_id.ib = NULL;
+		cma_exch(id_priv, CMA_DESTROYING);
+		cma_release_remove(id_priv);
+		rdma_destroy_id(&id_priv->id);
+		return ret;
+	}
+out:
+	cma_release_remove(id_priv);
+	return ret;
+}
+
+static struct rdma_id_private *cma_new_id(struct rdma_cm_id *listen_id,
+					  struct ib_cm_event *ib_event)
+{
+	struct rdma_id_private *id_priv;
+	struct rdma_cm_id *id;
+	struct rdma_route *rt;
+	union cma_ip_addr *src, *dst;
+	__u16 port;
+	u8 ip_ver;
+
+	id = rdma_create_id(listen_id->event_handler, listen_id->context,
+			    listen_id->ps);
+	if (IS_ERR(id))
+		return NULL;
+
+	rt = &id->route;
+	rt->num_paths = ib_event->param.req_rcvd.alternate_path ? 2 : 1;
+	rt->path_rec = kmalloc(sizeof *rt->path_rec * rt->num_paths, GFP_KERNEL);
+	if (!rt->path_rec)
+		goto err;
+
+	if (cma_get_net_info(ib_event->private_data, listen_id->ps,
+			     &ip_ver, &port, &src, &dst))
+		goto err;
+
+	cma_save_net_info(&id->route.addr, &listen_id->route.addr,
+			  ip_ver, port, src, dst);
+	rt->path_rec[0] = *ib_event->param.req_rcvd.primary_path;
+	if (rt->num_paths == 2)
+		rt->path_rec[1] = *ib_event->param.req_rcvd.alternate_path;
+
+	ib_addr_set_sgid(&rt->addr.dev_addr, &rt->path_rec[0].sgid);
+	ib_addr_set_dgid(&rt->addr.dev_addr, &rt->path_rec[0].dgid);
+	ib_addr_set_pkey(&rt->addr.dev_addr, be16_to_cpu(rt->path_rec[0].pkey));
+	rt->addr.dev_addr.dev_type = IB_NODE_CA;
+
+	id_priv = container_of(id, struct rdma_id_private, id);
+	id_priv->state = CMA_CONNECT;
+	return id_priv;
+err:
+	rdma_destroy_id(id);
+	return NULL;
+}
+
+static int cma_req_handler(struct ib_cm_id *cm_id, struct ib_cm_event *ib_event)
+{
+	struct rdma_id_private *listen_id, *conn_id;
+	int offset, ret;
+
+	listen_id = cm_id->context;
+	atomic_inc(&listen_id->dev_remove);
+	if (!cma_comp(listen_id, CMA_LISTEN)) {
+		ret = -ECONNABORTED;
+		goto out;
+	}
+
+	conn_id = cma_new_id(&listen_id->id, ib_event);
+	if (!conn_id) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	atomic_inc(&conn_id->dev_remove);
+	ret = cma_acquire_ib_dev(conn_id);
+	if (ret) {
+		ret = -ENODEV;
+		cma_release_remove(conn_id);
+		rdma_destroy_id(&conn_id->id);
+		goto out;
+	}
+
+	conn_id->cm_id.ib = cm_id;
+	cm_id->context = conn_id;
+	cm_id->cm_handler = cma_ib_handler;
+
+	offset = cma_user_data_offset(listen_id->id.ps);
+	ret = cma_notify_user(conn_id, RDMA_CM_EVENT_CONNECT_REQUEST, 0,
+			      ib_event->private_data + offset,
+			      IB_CM_REQ_PRIVATE_DATA_SIZE - offset);
+	if (ret) {
+		/* Destroy the CM ID by returning a non-zero value. */
+		conn_id->cm_id.ib = NULL;
+		cma_exch(conn_id, CMA_DESTROYING);
+		cma_release_remove(conn_id);
+		rdma_destroy_id(&conn_id->id);
+	}
+out:
+	cma_release_remove(listen_id);
+	return ret;
+}
+
+static __be64 cma_get_service_id(enum rdma_port_space ps, struct sockaddr *addr)
+{
+	return cpu_to_be64(((u64)ps << 16) +
+	       be16_to_cpu(((struct sockaddr_in *) addr)->sin_port));
+}
+
+static void cma_set_compare_data(enum rdma_port_space ps, struct sockaddr *addr,
+				 struct ib_cm_compare_data *compare)
+{
+	struct cma_hdr *cma_data, *cma_mask;
+	struct sdp_hh *sdp_data, *sdp_mask;
+	__u32 ip4_addr;
+	struct in6_addr ip6_addr;
+
+	memset(compare, 0, sizeof *compare);
+	cma_data = (void *) compare->data;
+	cma_mask = (void *) compare->mask;
+	sdp_data = (void *) compare->data;
+	sdp_mask = (void *) compare->mask;
+
+	switch (addr->sa_family) {
+	case AF_INET:
+		ip4_addr = ((struct sockaddr_in *) addr)->sin_addr.s_addr;
+		if (ps == RDMA_PS_SDP) {
+			sdp_set_ip_ver(sdp_data, 4);
+			sdp_set_ip_ver(sdp_mask, 0xF);
+			sdp_data->dst_addr.ip4.addr = ip4_addr;
+			sdp_mask->dst_addr.ip4.addr = ~0;
+		} else {
+			cma_set_ip_ver(cma_data, 4);
+			cma_set_ip_ver(cma_mask, 0xF);
+			cma_data->dst_addr.ip4.addr = ip4_addr;
+			cma_mask->dst_addr.ip4.addr = ~0;
+		}
+		break;
+	case AF_INET6:
+		ip6_addr = ((struct sockaddr_in6 *) addr)->sin6_addr;
+		if (ps == RDMA_PS_SDP) {
+			sdp_set_ip_ver(sdp_data, 6);
+			sdp_set_ip_ver(sdp_mask, 0xF);
+			sdp_data->dst_addr.ip6 = ip6_addr;
+			memset(&sdp_mask->dst_addr.ip6, 0xFF,
+			       sizeof sdp_mask->dst_addr.ip6);
+		} else {
+			cma_set_ip_ver(cma_data, 6);
+			cma_set_ip_ver(cma_mask, 0xF);
+			cma_data->dst_addr.ip6 = ip6_addr;
+			memset(&cma_mask->dst_addr.ip6, 0xFF,
+			       sizeof cma_mask->dst_addr.ip6);
+		}
+		break;
+	default:
+		break;
+	}
+}
+
+static int cma_ib_listen(struct rdma_id_private *id_priv)
+{
+	struct ib_cm_compare_data compare_data;
+	struct sockaddr *addr;
+	__be64 svc_id;
+	int ret;
+
+	id_priv->cm_id.ib = ib_create_cm_id(id_priv->id.device, cma_req_handler,
+					    id_priv);
+	if (IS_ERR(id_priv->cm_id.ib))
+		return PTR_ERR(id_priv->cm_id.ib);
+
+	addr = &id_priv->id.route.addr.src_addr;
+	svc_id = cma_get_service_id(id_priv->id.ps, addr);
+	if (cma_any_addr(addr))
+		ret = ib_cm_listen(id_priv->cm_id.ib, svc_id, 0, NULL);
+	else {
+		cma_set_compare_data(id_priv->id.ps, addr, &compare_data);
+		ret = ib_cm_listen(id_priv->cm_id.ib, svc_id, 0, &compare_data);
+	}
+
+	if (ret) {
+		ib_destroy_cm_id(id_priv->cm_id.ib);
+		id_priv->cm_id.ib = NULL;
+	}
+
+	return ret;
+}
+
+static int cma_listen_handler(struct rdma_cm_id *id,
+			      struct rdma_cm_event *event)
+{
+	struct rdma_id_private *id_priv = id->context;
+
+	id->context = id_priv->id.context;
+	id->event_handler = id_priv->id.event_handler;
+	return id_priv->id.event_handler(id, event);
+}
+
+static void cma_listen_on_dev(struct rdma_id_private *id_priv,
+			      struct cma_device *cma_dev)
+{
+	struct rdma_id_private *dev_id_priv;
+	struct rdma_cm_id *id;
+	int ret;
+
+	id = rdma_create_id(cma_listen_handler, id_priv, id_priv->id.ps);
+	if (IS_ERR(id))
+		return;
+
+	dev_id_priv = container_of(id, struct rdma_id_private, id);
+
+	dev_id_priv->state = CMA_ADDR_BOUND;
+	memcpy(&id->route.addr.src_addr, &id_priv->id.route.addr.src_addr,
+	       ip_addr_size(&id_priv->id.route.addr.src_addr));
+
+	cma_attach_to_dev(dev_id_priv, cma_dev);
+	list_add_tail(&dev_id_priv->listen_list, &id_priv->listen_list);
+
+	ret = rdma_listen(id, id_priv->backlog);
+	if (ret)
+		goto err;
+
+	return;
+err:
+	cma_destroy_listen(dev_id_priv);
+}
+
+static void cma_listen_on_all(struct rdma_id_private *id_priv)
+{
+	struct cma_device *cma_dev;
+
+	mutex_lock(&lock);
+	list_add_tail(&id_priv->list, &listen_any_list);
+	list_for_each_entry(cma_dev, &dev_list, list)
+		cma_listen_on_dev(id_priv, cma_dev);
+	mutex_unlock(&lock);
+}
+
+static int cma_bind_any(struct rdma_cm_id *id, sa_family_t af)
+{
+	struct sockaddr_in addr_in;
+
+	memset(&addr_in, 0, sizeof addr_in);
+	addr_in.sin_family = af;
+	return rdma_bind_addr(id, (struct sockaddr *) &addr_in);
+}
+
+int rdma_listen(struct rdma_cm_id *id, int backlog)
+{
+	struct rdma_id_private *id_priv;
+	int ret;
+
+	id_priv = container_of(id, struct rdma_id_private, id);
+	if (id_priv->state == CMA_IDLE) {
+		ret = cma_bind_any(id, AF_INET);
+		if (ret)
+			return ret;
+	}
+
+	if (!cma_comp_exch(id_priv, CMA_ADDR_BOUND, CMA_LISTEN))
+		return -EINVAL;
+
+	id_priv->backlog = backlog;
+	if (id->device) {
+		switch (id->device->node_type) {
+		case IB_NODE_CA:
+			ret = cma_ib_listen(id_priv);
+			if (ret)
+				goto err;
+			break;
+		default:
+			ret = -ENOSYS;
+			goto err;
+		}
+	} else
+		cma_listen_on_all(id_priv);
+
+	return 0;
+err:
+	id_priv->backlog = 0;
+	cma_comp_exch(id_priv, CMA_LISTEN, CMA_ADDR_BOUND);
+	return ret;
+}
+EXPORT_SYMBOL(rdma_listen);
+
+static void cma_query_handler(int status, struct ib_sa_path_rec *path_rec,
+			      void *context)
+{
+	struct cma_work *work = context;
+	struct rdma_route *route;
+
+	route = &work->id->id.route;
+
+	if (!status) {
+		route->num_paths = 1;
+		*route->path_rec = *path_rec;
+	} else {
+		work->old_state = CMA_ROUTE_QUERY;
+		work->new_state = CMA_ADDR_RESOLVED;
+		work->event.event = RDMA_CM_EVENT_ROUTE_ERROR;
+	}
+
+	queue_work(cma_wq, &work->work);
+}
+
+static int cma_query_ib_route(struct rdma_id_private *id_priv, int timeout_ms,
+			      struct cma_work *work)
+{
+	struct rdma_dev_addr *addr = &id_priv->id.route.addr.dev_addr;
+	struct ib_sa_path_rec path_rec;
+
+	memset(&path_rec, 0, sizeof path_rec);
+	path_rec.sgid = *ib_addr_get_sgid(addr);
+	path_rec.dgid = *ib_addr_get_dgid(addr);
+	path_rec.pkey = cpu_to_be16(ib_addr_get_pkey(addr));
+	path_rec.numb_path = 1;
+
+	id_priv->query_id = ib_sa_path_rec_get(id_priv->id.device,
+				id_priv->id.port_num, &path_rec,
+				IB_SA_PATH_REC_DGID | IB_SA_PATH_REC_SGID |
+				IB_SA_PATH_REC_PKEY | IB_SA_PATH_REC_NUMB_PATH,
+				timeout_ms, GFP_KERNEL,
+				cma_query_handler, work, &id_priv->query);
+
+	return (id_priv->query_id < 0) ? id_priv->query_id : 0;
+}
+
+static void cma_work_handler(void *data)
+{
+	struct cma_work *work = data;
+	struct rdma_id_private *id_priv = work->id;
+	int destroy = 0;
+
+	atomic_inc(&id_priv->dev_remove);
+	if (!cma_comp_exch(id_priv, work->old_state, work->new_state))
+		goto out;
+
+	if (id_priv->id.event_handler(&id_priv->id, &work->event)) {
+		cma_exch(id_priv, CMA_DESTROYING);
+		destroy = 1;
+	}
+out:
+	cma_release_remove(id_priv);
+	cma_deref_id(id_priv);
+	if (destroy)
+		rdma_destroy_id(&id_priv->id);
+	kfree(work);
+}
+
+static int cma_resolve_ib_route(struct rdma_id_private *id_priv, int timeout_ms)
+{
+	struct rdma_route *route = &id_priv->id.route;
+	struct cma_work *work;
+	int ret;
+
+	work = kzalloc(sizeof *work, GFP_KERNEL);
+	if (!work)
+		return -ENOMEM;
+
+	work->id = id_priv;
+	INIT_WORK(&work->work, cma_work_handler, work);
+	work->old_state = CMA_ROUTE_QUERY;
+	work->new_state = CMA_ROUTE_RESOLVED;
+	work->event.event = RDMA_CM_EVENT_ROUTE_RESOLVED;
+
+	route->path_rec = kmalloc(sizeof *route->path_rec, GFP_KERNEL);
+	if (!route->path_rec) {
+		ret = -ENOMEM;
+		goto err1;
+	}
+
+	ret = cma_query_ib_route(id_priv, timeout_ms, work);
+	if (ret)
+		goto err2;
+
+	return 0;
+err2:
+	kfree(route->path_rec);
+	route->path_rec = NULL;
+err1:
+	kfree(work);
+	return ret;
+}
+
+int rdma_set_ib_paths(struct rdma_cm_id *id,
+		      struct ib_sa_path_rec *path_rec, int num_paths)
+{
+	struct rdma_id_private *id_priv;
+	int ret;
+
+	id_priv = container_of(id, struct rdma_id_private, id);
+	if (!cma_comp_exch(id_priv, CMA_ADDR_RESOLVED, CMA_ROUTE_RESOLVED))
+		return -EINVAL;
+
+	id->route.path_rec = kmalloc(sizeof *path_rec * num_paths, GFP_KERNEL);
+	if (!id->route.path_rec) {
+		ret = -ENOMEM;
+		goto err;
+	}
+
+	memcpy(id->route.path_rec, path_rec, sizeof *path_rec * num_paths);
+	return 0;
+err:
+	cma_comp_exch(id_priv, CMA_ROUTE_RESOLVED, CMA_ADDR_RESOLVED);
+	return ret;
+}
+EXPORT_SYMBOL(rdma_set_ib_paths);
+
+int rdma_resolve_route(struct rdma_cm_id *id, int timeout_ms)
+{
+	struct rdma_id_private *id_priv;
+	int ret;
+
+	id_priv = container_of(id, struct rdma_id_private, id);
+	if (!cma_comp_exch(id_priv, CMA_ADDR_RESOLVED, CMA_ROUTE_QUERY))
+		return -EINVAL;
+
+	atomic_inc(&id_priv->refcount);
+	switch (id->device->node_type) {
+	case IB_NODE_CA:
+		ret = cma_resolve_ib_route(id_priv, timeout_ms);
+		break;
+	default:
+		ret = -ENOSYS;
+		break;
+	}
+	if (ret)
+		goto err;
+
+	return 0;
+err:
+	cma_comp_exch(id_priv, CMA_ROUTE_QUERY, CMA_ADDR_RESOLVED);
+	cma_deref_id(id_priv);
+	return ret;
+}
+EXPORT_SYMBOL(rdma_resolve_route);
+
+static int cma_bind_loopback(struct rdma_id_private *id_priv)
+{
+	struct cma_device *cma_dev;
+	struct ib_port_attr port_attr;
+	union ib_gid *gid;
+	u16 pkey;
+	int ret;
+	u8 p;
+
+	mutex_lock(&lock);
+	list_for_each_entry(cma_dev, &dev_list, list)
+		for (p = 1; p <= cma_dev->device->phys_port_cnt; ++p)
+			if (!ib_query_port (cma_dev->device, p, &port_attr) &&
+			    port_attr.state == IB_PORT_ACTIVE)
+				goto port_found;
+
+	if (!list_empty(&dev_list)) {
+		p = 1;
+		cma_dev = list_entry(dev_list.next, struct cma_device, list);
+	} else {
+		ret = -ENODEV;
+		goto out;
+	}
+
+port_found:
+	gid = ib_addr_get_sgid(&id_priv->id.route.addr.dev_addr);
+	ret = ib_get_cached_gid(cma_dev->device, p, 0, gid);
+	if (ret)
+		goto out;
+
+	ret = ib_get_cached_pkey(cma_dev->device, p, 0, &pkey);
+	if (ret)
+		goto out;
+
+	ib_addr_set_pkey(&id_priv->id.route.addr.dev_addr, pkey);
+	id_priv->id.port_num = p;
+	cma_attach_to_dev(id_priv, cma_dev);
+out:
+	mutex_unlock(&lock);
+	return ret;
+}
+
+static void addr_handler(int status, struct sockaddr *src_addr,
+			 struct rdma_dev_addr *dev_addr, void *context)
+{
+	struct rdma_id_private *id_priv = context;
+	enum rdma_cm_event_type event;
+
+	atomic_inc(&id_priv->dev_remove);
+	if (!id_priv->cma_dev && !status)
+		status = cma_acquire_dev(id_priv);
+
+	if (status) {
+		if (!cma_comp_exch(id_priv, CMA_ADDR_QUERY, CMA_ADDR_BOUND))
+			goto out;
+		event = RDMA_CM_EVENT_ADDR_ERROR;
+	} else {
+		if (!cma_comp_exch(id_priv, CMA_ADDR_QUERY, CMA_ADDR_RESOLVED))
+			goto out;
+		memcpy(&id_priv->id.route.addr.src_addr, src_addr,
+		       ip_addr_size(src_addr));
+		event = RDMA_CM_EVENT_ADDR_RESOLVED;
+	}
+
+	if (cma_notify_user(id_priv, event, status, NULL, 0)) {
+		cma_exch(id_priv, CMA_DESTROYING);
+		cma_release_remove(id_priv);
+		cma_deref_id(id_priv);
+		rdma_destroy_id(&id_priv->id);
+		return;
+	}
+out:
+	cma_release_remove(id_priv);
+	cma_deref_id(id_priv);
+}
+
+static int cma_resolve_loopback(struct rdma_id_private *id_priv)
+{
+	struct cma_work *work;
+	struct sockaddr_in *src_in, *dst_in;
+	int ret;
+
+	work = kzalloc(sizeof *work, GFP_KERNEL);
+	if (!work)
+		return -ENOMEM;
+
+	if (!id_priv->cma_dev) {
+		ret = cma_bind_loopback(id_priv);
+		if (ret)
+			goto err;
+	}
+
+	ib_addr_set_dgid(&id_priv->id.route.addr.dev_addr,
+			 ib_addr_get_sgid(&id_priv->id.route.addr.dev_addr));
+
+	if (cma_zero_addr(&id_priv->id.route.addr.src_addr)) {
+		src_in = (struct sockaddr_in *)&id_priv->id.route.addr.src_addr;
+		dst_in = (struct sockaddr_in *)&id_priv->id.route.addr.dst_addr;
+		src_in->sin_family = dst_in->sin_family;
+		src_in->sin_addr.s_addr = dst_in->sin_addr.s_addr;
+	}
+
+	work->id = id_priv;
+	INIT_WORK(&work->work, cma_work_handler, work);
+	work->old_state = CMA_ADDR_QUERY;
+	work->new_state = CMA_ADDR_RESOLVED;
+	work->event.event = RDMA_CM_EVENT_ADDR_RESOLVED;
+	queue_work(cma_wq, &work->work);
+	return 0;
+err:
+	kfree(work);
+	return ret;
+}
+
+static int cma_bind_addr(struct rdma_cm_id *id, struct sockaddr *src_addr,
+			 struct sockaddr *dst_addr)
+{
+	if (src_addr && src_addr->sa_family)
+		return rdma_bind_addr(id, src_addr);
+	else
+		return cma_bind_any(id, dst_addr->sa_family);
+}
+
+int rdma_resolve_addr(struct rdma_cm_id *id, struct sockaddr *src_addr,
+		      struct sockaddr *dst_addr, int timeout_ms)
+{
+	struct rdma_id_private *id_priv;
+	int ret;
+
+	id_priv = container_of(id, struct rdma_id_private, id);
+	if (id_priv->state == CMA_IDLE) {
+		ret = cma_bind_addr(id, src_addr, dst_addr);
+		if (ret)
+			return ret;
+	}
+
+	if (!cma_comp_exch(id_priv, CMA_ADDR_BOUND, CMA_ADDR_QUERY))
+		return -EINVAL;
+
+	atomic_inc(&id_priv->refcount);
+	memcpy(&id->route.addr.dst_addr, dst_addr, ip_addr_size(dst_addr));
+	if (cma_any_addr(dst_addr))
+		ret = cma_resolve_loopback(id_priv);
+	else
+		ret = rdma_resolve_ip(&id->route.addr.src_addr, dst_addr,
+				      &id->route.addr.dev_addr,
+				      timeout_ms, addr_handler, id_priv);
+	if (ret)
+		goto err;
+
+	return 0;
+err:
+	cma_comp_exch(id_priv, CMA_ADDR_QUERY, CMA_ADDR_BOUND);
+	cma_deref_id(id_priv);
+	return ret;
+}
+EXPORT_SYMBOL(rdma_resolve_addr);
+
+static void cma_bind_port(struct rdma_bind_list *bind_list,
+			  struct rdma_id_private *id_priv)
+{
+	struct sockaddr_in *sin;
+
+	sin = (struct sockaddr_in *) &id_priv->id.route.addr.src_addr;
+	sin->sin_port = htons(bind_list->port);
+	id_priv->bind_list = bind_list;
+	hlist_add_head(&id_priv->node, &bind_list->owners);
+}
+
+static int cma_alloc_port(struct idr *ps, struct rdma_id_private *id_priv,
+			  unsigned short snum)
+{
+	struct rdma_bind_list *bind_list;
+	int port, start, ret;
+
+	bind_list = kzalloc(sizeof *bind_list, GFP_KERNEL);
+	if (!bind_list)
+		return -ENOMEM;
+
+	start = snum ? snum : sysctl_local_port_range[0];
+
+	do {
+		ret = idr_get_new_above(ps, bind_list, start, &port);
+	} while ((ret == -EAGAIN) && idr_pre_get(ps, GFP_KERNEL));
+
+	if (ret)
+		goto err;
+
+	if ((snum && port != snum) ||
+	    (!snum && port > sysctl_local_port_range[1])) {
+		idr_remove(ps, port);
+		ret = -EADDRNOTAVAIL;
+		goto err;
+	}
+
+	bind_list->ps = ps;
+	bind_list->port = (unsigned short) port;
+	cma_bind_port(bind_list, id_priv);
+	return 0;
+err:
+	kfree(bind_list);
+	return ret;
+}
+
+static int cma_use_port(struct idr *ps, struct rdma_id_private *id_priv)
+{
+	struct rdma_id_private *cur_id;
+	struct sockaddr_in *sin, *cur_sin;
+	struct rdma_bind_list *bind_list;
+	struct hlist_node *node;
+	unsigned short snum;
+
+	sin = (struct sockaddr_in *) &id_priv->id.route.addr.src_addr;
+	snum = ntohs(sin->sin_port);
+	if (snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
+		return -EACCES;
+
+	bind_list = idr_find(ps, snum);
+	if (!bind_list)
+		return cma_alloc_port(ps, id_priv, snum);
+
+	/*
+	 * We don't support binding to any address if anyone is bound to
+	 * a specific address on the same port.
+	 */
+	if (cma_any_addr(&id_priv->id.route.addr.src_addr))
+		return -EADDRNOTAVAIL;
+
+	hlist_for_each_entry(cur_id, node, &bind_list->owners, node) {
+		if (cma_any_addr(&cur_id->id.route.addr.src_addr))
+			return -EADDRNOTAVAIL;
+		
+		cur_sin = (struct sockaddr_in *) &cur_id->id.route.addr.src_addr;
+		if (sin->sin_addr.s_addr == cur_sin->sin_addr.s_addr)
+			return -EADDRINUSE;
+	}
+
+	cma_bind_port(bind_list, id_priv);
+	return 0;
+}
+
+static int cma_get_port(struct rdma_id_private *id_priv)
+{
+	struct idr *ps;
+	int ret;
+
+	switch (id_priv->id.ps) {
+	case RDMA_PS_SDP:
+		ps = &sdp_ps;
+		break;
+	case RDMA_PS_TCP:
+		ps = &tcp_ps;
+		break;
+	default:
+		return -EPROTONOSUPPORT;
+	}
+
+	mutex_lock(&lock);
+	if (cma_any_port(&id_priv->id.route.addr.src_addr))
+		ret = cma_alloc_port(ps, id_priv, 0);
+	else
+		ret = cma_use_port(ps, id_priv);
+	mutex_unlock(&lock);
+
+	return ret;
+}
+
+int rdma_bind_addr(struct rdma_cm_id *id, struct sockaddr *addr)
+{
+	struct rdma_id_private *id_priv;
+	int ret;
+
+	if (addr->sa_family != AF_INET)
+		return -EAFNOSUPPORT;
+
+	id_priv = container_of(id, struct rdma_id_private, id);
+	if (!cma_comp_exch(id_priv, CMA_IDLE, CMA_ADDR_BOUND))
+		return -EINVAL;
+
+	if (!cma_any_addr(addr)) {
+		ret = rdma_translate_ip(addr, &id->route.addr.dev_addr);
+		if (!ret)
+			ret = cma_acquire_dev(id_priv);
+		if (ret)
+			goto err;
+	}
+
+	memcpy(&id->route.addr.src_addr, addr, ip_addr_size(addr));
+	ret = cma_get_port(id_priv);
+	if (ret)
+		goto err;
+
+	return 0;
+err:
+	cma_comp_exch(id_priv, CMA_ADDR_BOUND, CMA_IDLE);
+	return ret;
+}
+EXPORT_SYMBOL(rdma_bind_addr);
+
+static int cma_format_hdr(void *hdr, enum rdma_port_space ps,
+			  struct rdma_route *route)
+{
+	struct sockaddr_in *src4, *dst4;
+	struct cma_hdr *cma_hdr;
+	struct sdp_hh *sdp_hdr;
+
+	src4 = (struct sockaddr_in *) &route->addr.src_addr;
+	dst4 = (struct sockaddr_in *) &route->addr.dst_addr;
+
+	switch (ps) {
+	case RDMA_PS_SDP:
+		sdp_hdr = hdr;
+		if (sdp_get_majv(sdp_hdr->sdp_version) != SDP_MAJ_VERSION)
+			return -EINVAL;
+		sdp_set_ip_ver(sdp_hdr, 4);
+		sdp_hdr->src_addr.ip4.addr = src4->sin_addr.s_addr;
+		sdp_hdr->dst_addr.ip4.addr = dst4->sin_addr.s_addr;
+		sdp_hdr->port = src4->sin_port;
+		break;
+	default:
+		cma_hdr = hdr;
+		cma_hdr->cma_version = CMA_VERSION;
+		cma_set_ip_ver(cma_hdr, 4);
+		cma_hdr->src_addr.ip4.addr = src4->sin_addr.s_addr;
+		cma_hdr->dst_addr.ip4.addr = dst4->sin_addr.s_addr;
+		cma_hdr->port = src4->sin_port;
+		break;
+	}
+	return 0;
+}
+
+static int cma_connect_ib(struct rdma_id_private *id_priv,
+			  struct rdma_conn_param *conn_param)
+{
+	struct ib_cm_req_param req;
+	struct rdma_route *route;
+	void *private_data;
+	int offset, ret;
+
+	memset(&req, 0, sizeof req);
+	offset = cma_user_data_offset(id_priv->id.ps);
+	req.private_data_len = offset + conn_param->private_data_len;
+	private_data = kzalloc(req.private_data_len, GFP_ATOMIC);
+	if (!private_data)
+		return -ENOMEM;
+
+	if (conn_param->private_data && conn_param->private_data_len)
+		memcpy(private_data + offset, conn_param->private_data,
+		       conn_param->private_data_len);
+
+	id_priv->cm_id.ib = ib_create_cm_id(id_priv->id.device, cma_ib_handler,
+					    id_priv);
+	if (IS_ERR(id_priv->cm_id.ib)) {
+		ret = PTR_ERR(id_priv->cm_id.ib);
+		goto out;
+	}
+
+	route = &id_priv->id.route;
+	ret = cma_format_hdr(private_data, id_priv->id.ps, route);
+	if (ret)
+		goto out;
+	req.private_data = private_data;
+
+	req.primary_path = &route->path_rec[0];
+	if (route->num_paths == 2)
+		req.alternate_path = &route->path_rec[1];
+
+	req.service_id = cma_get_service_id(id_priv->id.ps,
+					    &route->addr.dst_addr);
+	req.qp_num = id_priv->qp_num;
+	req.qp_type = id_priv->qp_type;
+	req.starting_psn = id_priv->seq_num;
+	req.responder_resources = conn_param->responder_resources;
+	req.initiator_depth = conn_param->initiator_depth;
+	req.flow_control = conn_param->flow_control;
+	req.retry_count = conn_param->retry_count;
+	req.rnr_retry_count = conn_param->rnr_retry_count;
+	req.remote_cm_response_timeout = CMA_CM_RESPONSE_TIMEOUT;
+	req.local_cm_response_timeout = CMA_CM_RESPONSE_TIMEOUT;
+	req.max_cm_retries = CMA_MAX_CM_RETRIES;
+	req.srq = id_priv->srq ? 1 : 0;
+
+	ret = ib_send_cm_req(id_priv->cm_id.ib, &req);
+out:
+	kfree(private_data);
+	return ret;
+}
+
+int rdma_connect(struct rdma_cm_id *id, struct rdma_conn_param *conn_param)
+{
+	struct rdma_id_private *id_priv;
+	int ret;
+
+	id_priv = container_of(id, struct rdma_id_private, id);
+	if (!cma_comp_exch(id_priv, CMA_ROUTE_RESOLVED, CMA_CONNECT))
+		return -EINVAL;
+
+	if (!id->qp) {
+		id_priv->qp_num = conn_param->qp_num;
+		id_priv->qp_type = conn_param->qp_type;
+		id_priv->srq = conn_param->srq;
+	}
+
+	switch (id->device->node_type) {
+	case IB_NODE_CA:
+		ret = cma_connect_ib(id_priv, conn_param);
+		break;
+	default:
+		ret = -ENOSYS;
+		break;
+	}
+	if (ret)
+		goto err;
+
+	return 0;
+err:
+	cma_comp_exch(id_priv, CMA_CONNECT, CMA_ROUTE_RESOLVED);
+	return ret;
+}
+EXPORT_SYMBOL(rdma_connect);
+
+static int cma_accept_ib(struct rdma_id_private *id_priv,
+			 struct rdma_conn_param *conn_param)
+{
+	struct ib_cm_rep_param rep;
+	int ret;
+
+	ret = cma_modify_qp_rtr(&id_priv->id);
+	if (ret)
+		return ret;
+
+	memset(&rep, 0, sizeof rep);
+	rep.qp_num = id_priv->qp_num;
+	rep.starting_psn = id_priv->seq_num;
+	rep.private_data = conn_param->private_data;
+	rep.private_data_len = conn_param->private_data_len;
+	rep.responder_resources = conn_param->responder_resources;
+	rep.initiator_depth = conn_param->initiator_depth;
+	rep.target_ack_delay = CMA_CM_RESPONSE_TIMEOUT;
+	rep.failover_accepted = 0;
+	rep.flow_control = conn_param->flow_control;
+	rep.rnr_retry_count = conn_param->rnr_retry_count;
+	rep.srq = id_priv->srq ? 1 : 0;
+
+	return ib_send_cm_rep(id_priv->cm_id.ib, &rep);
+}
+
+int rdma_accept(struct rdma_cm_id *id, struct rdma_conn_param *conn_param)
+{
+	struct rdma_id_private *id_priv;
+	int ret;
+
+	id_priv = container_of(id, struct rdma_id_private, id);
+	if (!cma_comp(id_priv, CMA_CONNECT))
+		return -EINVAL;
+
+	if (!id->qp && conn_param) {
+		id_priv->qp_num = conn_param->qp_num;
+		id_priv->qp_type = conn_param->qp_type;
+		id_priv->srq = conn_param->srq;
+	}
+
+	switch (id->device->node_type) {
+	case IB_NODE_CA:
+		if (conn_param)
+			ret = cma_accept_ib(id_priv, conn_param);
+		else
+			ret = cma_rep_recv(id_priv);
+		break;
+	default:
+		ret = -ENOSYS;
+		break;
+	}
+
+	if (ret)
+		goto reject;
+
+	return 0;
+reject:
+	cma_modify_qp_err(id);
+	rdma_reject(id, NULL, 0);
+	return ret;
+}
+EXPORT_SYMBOL(rdma_accept);
+
+int rdma_reject(struct rdma_cm_id *id, const void *private_data,
+		u8 private_data_len)
+{
+	struct rdma_id_private *id_priv;
+	int ret;
+
+	id_priv = container_of(id, struct rdma_id_private, id);
+	if (!cma_comp(id_priv, CMA_CONNECT))
+		return -EINVAL;
+
+	switch (id->device->node_type) {
+	case IB_NODE_CA:
+		ret = ib_send_cm_rej(id_priv->cm_id.ib,
+				     IB_CM_REJ_CONSUMER_DEFINED, NULL, 0,
+				     private_data, private_data_len);
+		break;
+	default:
+		ret = -ENOSYS;
+		break;
+	}
+	return ret;
+}
+EXPORT_SYMBOL(rdma_reject);
+
+int rdma_disconnect(struct rdma_cm_id *id)
+{
+	struct rdma_id_private *id_priv;
+	int ret;
+
+	id_priv = container_of(id, struct rdma_id_private, id);
+	if (!cma_comp(id_priv, CMA_CONNECT) &&
+	    !cma_comp(id_priv, CMA_DISCONNECT))
+		return -EINVAL;
+
+	ret = cma_modify_qp_err(id);
+	if (ret)
+		goto out;
+
+	switch (id->device->node_type) {
+	case IB_NODE_CA:
+		/* Initiate or respond to a disconnect. */
+		if (ib_send_cm_dreq(id_priv->cm_id.ib, NULL, 0))
+			ib_send_cm_drep(id_priv->cm_id.ib, NULL, 0);
+		break;
+	default:
+		break;
+	}
+out:
+	return ret;
+}
+EXPORT_SYMBOL(rdma_disconnect);
+
+static void cma_add_one(struct ib_device *device)
+{
+	struct cma_device *cma_dev;
+	struct rdma_id_private *id_priv;
+
+	cma_dev = kmalloc(sizeof *cma_dev, GFP_KERNEL);
+	if (!cma_dev)
+		return;
+
+	cma_dev->device = device;
+	cma_dev->node_guid = device->node_guid;
+	if (!cma_dev->node_guid)
+		goto err;
+
+	init_completion(&cma_dev->comp);
+	atomic_set(&cma_dev->refcount, 1);
+	INIT_LIST_HEAD(&cma_dev->id_list);
+	ib_set_client_data(device, &cma_client, cma_dev);
+
+	mutex_lock(&lock);
+	list_add_tail(&cma_dev->list, &dev_list);
+	list_for_each_entry(id_priv, &listen_any_list, list)
+		cma_listen_on_dev(id_priv, cma_dev);
+	mutex_unlock(&lock);
+	return;
+err:
+	kfree(cma_dev);
+}
+
+static int cma_remove_id_dev(struct rdma_id_private *id_priv)
+{
+	enum cma_state state;
+
+	/* Record that we want to remove the device */
+	state = cma_exch(id_priv, CMA_DEVICE_REMOVAL);
+	if (state == CMA_DESTROYING)
+		return 0;
+
+	cma_cancel_operation(id_priv, state);
+	wait_event(id_priv->wait_remove, !atomic_read(&id_priv->dev_remove));
+
+	/* Check for destruction from another callback. */
+	if (!cma_comp(id_priv, CMA_DEVICE_REMOVAL))
+		return 0;
+
+	return cma_notify_user(id_priv, RDMA_CM_EVENT_DEVICE_REMOVAL,
+			       0, NULL, 0);
+}
+
+static void cma_process_remove(struct cma_device *cma_dev)
+{
+	struct list_head remove_list;
+	struct rdma_id_private *id_priv;
+	int ret;
+
+	INIT_LIST_HEAD(&remove_list);
+
+	mutex_lock(&lock);
+	while (!list_empty(&cma_dev->id_list)) {
+		id_priv = list_entry(cma_dev->id_list.next,
+				     struct rdma_id_private, list);
+
+		if (cma_internal_listen(id_priv)) {
+			cma_destroy_listen(id_priv);
+			continue;
+		}
+
+		list_del(&id_priv->list);
+		list_add_tail(&id_priv->list, &remove_list);
+		atomic_inc(&id_priv->refcount);
+		mutex_unlock(&lock);
+
+		ret = cma_remove_id_dev(id_priv);
+		cma_deref_id(id_priv);
+		if (ret)
+			rdma_destroy_id(&id_priv->id);
+
+		mutex_lock(&lock);
+	}
+	mutex_unlock(&lock);
+
+	cma_deref_dev(cma_dev);
+	wait_for_completion(&cma_dev->comp);
+}
+
+static void cma_remove_one(struct ib_device *device)
+{
+	struct cma_device *cma_dev;
+
+	cma_dev = ib_get_client_data(device, &cma_client);
+	if (!cma_dev)
+		return;
+
+	mutex_lock(&lock);
+	list_del(&cma_dev->list);
+	mutex_unlock(&lock);
+
+	cma_process_remove(cma_dev);
+	kfree(cma_dev);
+}
+
+static int cma_init(void)
+{
+	int ret;
+
+	cma_wq = create_singlethread_workqueue("rdma_cm_wq");
+	if (!cma_wq)
+		return -ENOMEM;
+
+	ret = ib_register_client(&cma_client);
+	if (ret)
+		goto err;
+	return 0;
+
+err:
+	destroy_workqueue(cma_wq);
+	return ret;
+}
+
+static void cma_cleanup(void)
+{
+	ib_unregister_client(&cma_client);
+	destroy_workqueue(cma_wq);
+	idr_destroy(&sdp_ps);
+	idr_destroy(&tcp_ps);
+}
+
+module_init(cma_init);
+module_exit(cma_cleanup);