[PATCH] IB: Add the kernel CM implementation

Add the kernel CM implementation

Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Hal Rosenstock <halr@voltaire.com>
Cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

3 files changed, 4147 insertions, 1 deletions

diff --git a/drivers/infiniband/core/Makefile b/drivers/infiniband/core/Makefile
index 96b8eba9584..216cb281abd 100644
--- a/drivers/infiniband/core/Makefile
+++ b/drivers/infiniband/core/Makefile
@@ -1,6 +1,7 @@
 EXTRA_CFLAGS += -Idrivers/infiniband/include
 
-obj-$(CONFIG_INFINIBAND) +=		ib_core.o ib_mad.o ib_sa.o ib_umad.o
+obj-$(CONFIG_INFINIBAND) +=		ib_core.o ib_mad.o ib_sa.o \
+					ib_cm.o ib_umad.o
 obj-$(CONFIG_INFINIBAND_USER_VERBS) +=	ib_uverbs.o
 
 ib_core-y :=			packer.o ud_header.o verbs.o sysfs.o \
@@ -10,6 +11,8 @@ ib_mad-y :=			mad.o smi.o agent.o mad_rmpp.o
 
 ib_sa-y :=			sa_query.o
 
+ib_cm-y :=			cm.o
+
 ib_umad-y :=			user_mad.o
 
 ib_uverbs-y :=			uverbs_main.o uverbs_cmd.o uverbs_mem.o
diff --git a/drivers/infiniband/core/cm.c b/drivers/infiniband/core/cm.c
new file mode 100644
index 00000000000..403ed125d8f
--- /dev/null
+++ b/drivers/infiniband/core/cm.c
@@ -0,0 +1,3324 @@
+/*
+ * Copyright (c) 2004, 2005 Intel Corporation.  All rights reserved.
+ * Copyright (c) 2004 Topspin Corporation.  All rights reserved.
+ * Copyright (c) 2004, 2005 Voltaire Corporation.  All rights reserved.
+ * Copyright (c) 2005 Sun Microsystems, Inc. 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.
+ *
+ * $Id: cm.c 2821 2005-07-08 17:07:28Z sean.hefty $
+ */
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/idr.h>
+#include <linux/interrupt.h>
+#include <linux/pci.h>
+#include <linux/rbtree.h>
+#include <linux/spinlock.h>
+#include <linux/workqueue.h>
+
+#include <ib_cache.h>
+#include <ib_cm.h>
+#include "cm_msgs.h"
+
+MODULE_AUTHOR("Sean Hefty");
+MODULE_DESCRIPTION("InfiniBand CM");
+MODULE_LICENSE("Dual BSD/GPL");
+
+static void cm_add_one(struct ib_device *device);
+static void cm_remove_one(struct ib_device *device);
+
+static struct ib_client cm_client = {
+	.name   = "cm",
+	.add    = cm_add_one,
+	.remove = cm_remove_one
+};
+
+static struct ib_cm {
+	spinlock_t lock;
+	struct list_head device_list;
+	rwlock_t device_lock;
+	struct rb_root listen_service_table;
+	u64 listen_service_id;
+	/* struct rb_root peer_service_table; todo: fix peer to peer */
+	struct rb_root remote_qp_table;
+	struct rb_root remote_id_table;
+	struct rb_root remote_sidr_table;
+	struct idr local_id_table;
+	struct workqueue_struct *wq;
+} cm;
+
+struct cm_port {
+	struct cm_device *cm_dev;
+	struct ib_mad_agent *mad_agent;
+	u8 port_num;
+};
+
+struct cm_device {
+	struct list_head list;
+	struct ib_device *device;
+	u64 ca_guid;
+	struct cm_port port[0];
+};
+
+struct cm_av {
+	struct cm_port *port;
+	union ib_gid dgid;
+	struct ib_ah_attr ah_attr;
+	u16 pkey_index;
+	u8 packet_life_time;
+};
+
+struct cm_work {
+	struct work_struct work;
+	struct list_head list;
+	struct cm_port *port;
+	struct ib_mad_recv_wc *mad_recv_wc;	/* Received MADs */
+	u32 local_id;				/* Established / timewait */
+	u32 remote_id;
+	struct ib_cm_event cm_event;
+	struct ib_sa_path_rec path[0];
+};
+
+struct cm_timewait_info {
+	struct cm_work work;			/* Must be first. */
+	struct rb_node remote_qp_node;
+	struct rb_node remote_id_node;
+	u64 remote_ca_guid;
+	u32 remote_qpn;
+	u8 inserted_remote_qp;
+	u8 inserted_remote_id;
+};
+
+struct cm_id_private {
+	struct ib_cm_id	id;
+
+	struct rb_node service_node;
+	struct rb_node sidr_id_node;
+	spinlock_t lock;
+	wait_queue_head_t wait;
+	atomic_t refcount;
+
+	struct ib_mad_send_buf *msg;
+	struct cm_timewait_info *timewait_info;
+	/* todo: use alternate port on send failure */
+	struct cm_av av;
+	struct cm_av alt_av;
+
+	void *private_data;
+	u64 tid;
+	u32 local_qpn;
+	u32 remote_qpn;
+	u32 sq_psn;
+	u32 rq_psn;
+	int timeout_ms;
+	enum ib_mtu path_mtu;
+	u8 private_data_len;
+	u8 max_cm_retries;
+	u8 peer_to_peer;
+	u8 responder_resources;
+	u8 initiator_depth;
+	u8 local_ack_timeout;
+	u8 retry_count;
+	u8 rnr_retry_count;
+	u8 service_timeout;
+
+	struct list_head work_list;
+	atomic_t work_count;
+};
+
+static void cm_work_handler(void *data);
+
+static inline void cm_deref_id(struct cm_id_private *cm_id_priv)
+{
+	if (atomic_dec_and_test(&cm_id_priv->refcount))
+		wake_up(&cm_id_priv->wait);
+}
+
+static int cm_alloc_msg(struct cm_id_private *cm_id_priv,
+			struct ib_mad_send_buf **msg)
+{
+	struct ib_mad_agent *mad_agent;
+	struct ib_mad_send_buf *m;
+	struct ib_ah *ah;
+
+	mad_agent = cm_id_priv->av.port->mad_agent;
+	ah = ib_create_ah(mad_agent->qp->pd, &cm_id_priv->av.ah_attr);
+	if (IS_ERR(ah))
+		return PTR_ERR(ah);
+
+	m = ib_create_send_mad(mad_agent, 1, cm_id_priv->av.pkey_index,
+			       ah, 0, sizeof(struct ib_mad_hdr),
+			       sizeof(struct ib_mad)-sizeof(struct ib_mad_hdr),
+			       GFP_ATOMIC);
+	if (IS_ERR(m)) {
+		ib_destroy_ah(ah);
+		return PTR_ERR(m);
+	}
+
+	/* Timeout set by caller if response is expected. */
+	m->send_wr.wr.ud.retries = cm_id_priv->max_cm_retries;
+
+	atomic_inc(&cm_id_priv->refcount);
+	m->context[0] = cm_id_priv;
+	*msg = m;
+	return 0;
+}
+
+static int cm_alloc_response_msg(struct cm_port *port,
+				 struct ib_mad_recv_wc *mad_recv_wc,
+				 struct ib_mad_send_buf **msg)
+{
+	struct ib_mad_send_buf *m;
+	struct ib_ah *ah;
+
+	ah = ib_create_ah_from_wc(port->mad_agent->qp->pd, mad_recv_wc->wc,
+				  mad_recv_wc->recv_buf.grh, port->port_num);
+	if (IS_ERR(ah))
+		return PTR_ERR(ah);
+
+	m = ib_create_send_mad(port->mad_agent, 1, mad_recv_wc->wc->pkey_index,
+			       ah, 0, sizeof(struct ib_mad_hdr),
+			       sizeof(struct ib_mad)-sizeof(struct ib_mad_hdr),
+			       GFP_ATOMIC);
+	if (IS_ERR(m)) {
+		ib_destroy_ah(ah);
+		return PTR_ERR(m);
+	}
+	*msg = m;
+	return 0;
+}
+
+static void cm_free_msg(struct ib_mad_send_buf *msg)
+{
+	ib_destroy_ah(msg->send_wr.wr.ud.ah);
+	if (msg->context[0])
+		cm_deref_id(msg->context[0]);
+	ib_free_send_mad(msg);
+}
+
+static void * cm_copy_private_data(const void *private_data,
+				   u8 private_data_len)
+{
+	void *data;
+
+	if (!private_data || !private_data_len)
+		return NULL;
+
+	data = kmalloc(private_data_len, GFP_KERNEL);
+	if (!data)
+		return ERR_PTR(-ENOMEM);
+
+	memcpy(data, private_data, private_data_len);
+	return data;
+}
+
+static void cm_set_private_data(struct cm_id_private *cm_id_priv,
+				 void *private_data, u8 private_data_len)
+{
+	if (cm_id_priv->private_data && cm_id_priv->private_data_len)
+		kfree(cm_id_priv->private_data);
+
+	cm_id_priv->private_data = private_data;
+	cm_id_priv->private_data_len = private_data_len;
+}
+
+static void cm_set_ah_attr(struct ib_ah_attr *ah_attr, u8 port_num,
+			   u16 dlid, u8 sl, u16 src_path_bits)
+{
+	memset(ah_attr, 0, sizeof ah_attr);
+	ah_attr->dlid = be16_to_cpu(dlid);
+	ah_attr->sl = sl;
+	ah_attr->src_path_bits = src_path_bits;
+	ah_attr->port_num = port_num;
+}
+
+static void cm_init_av_for_response(struct cm_port *port,
+				    struct ib_wc *wc, struct cm_av *av)
+{
+	av->port = port;
+	av->pkey_index = wc->pkey_index;
+	cm_set_ah_attr(&av->ah_attr, port->port_num, cpu_to_be16(wc->slid),
+		       wc->sl, wc->dlid_path_bits);
+}
+
+static int cm_init_av_by_path(struct ib_sa_path_rec *path, struct cm_av *av)
+{
+	struct cm_device *cm_dev;
+	struct cm_port *port = NULL;
+	unsigned long flags;
+	int ret;
+	u8 p;
+
+	read_lock_irqsave(&cm.device_lock, flags);
+	list_for_each_entry(cm_dev, &cm.device_list, list) {
+		if (!ib_find_cached_gid(cm_dev->device, &path->sgid,
+					&p, NULL)) {
+			port = &cm_dev->port[p-1];
+			break;
+		}
+	}
+	read_unlock_irqrestore(&cm.device_lock, flags);
+
+	if (!port)
+		return -EINVAL;
+
+	ret = ib_find_cached_pkey(cm_dev->device, port->port_num,
+				  be16_to_cpu(path->pkey), &av->pkey_index);
+	if (ret)
+		return ret;
+
+	av->port = port;
+	cm_set_ah_attr(&av->ah_attr, av->port->port_num, path->dlid,
+		       path->sl, path->slid & 0x7F);
+	av->packet_life_time = path->packet_life_time;
+	return 0;
+}
+
+static int cm_alloc_id(struct cm_id_private *cm_id_priv)
+{
+	unsigned long flags;
+	int ret;
+
+	do {
+		spin_lock_irqsave(&cm.lock, flags);
+		ret = idr_get_new_above(&cm.local_id_table, cm_id_priv, 1,
+					(int *) &cm_id_priv->id.local_id);
+		spin_unlock_irqrestore(&cm.lock, flags);
+	} while( (ret == -EAGAIN) && idr_pre_get(&cm.local_id_table, GFP_KERNEL) );
+	return ret;
+}
+
+static void cm_free_id(u32 local_id)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&cm.lock, flags);
+	idr_remove(&cm.local_id_table, (int) local_id);
+	spin_unlock_irqrestore(&cm.lock, flags);
+}
+
+static struct cm_id_private * cm_get_id(u32 local_id, u32 remote_id)
+{
+	struct cm_id_private *cm_id_priv;
+
+	cm_id_priv = idr_find(&cm.local_id_table, (int) local_id);
+	if (cm_id_priv) {
+		if (cm_id_priv->id.remote_id == remote_id)
+			atomic_inc(&cm_id_priv->refcount);
+		else
+			cm_id_priv = NULL;
+	}
+
+	return cm_id_priv;
+}
+
+static struct cm_id_private * cm_acquire_id(u32 local_id, u32 remote_id)
+{
+	struct cm_id_private *cm_id_priv;
+	unsigned long flags;
+
+	spin_lock_irqsave(&cm.lock, flags);
+	cm_id_priv = cm_get_id(local_id, remote_id);
+	spin_unlock_irqrestore(&cm.lock, flags);
+
+	return cm_id_priv;
+}
+
+static struct cm_id_private * cm_insert_listen(struct cm_id_private *cm_id_priv)
+{
+	struct rb_node **link = &cm.listen_service_table.rb_node;
+	struct rb_node *parent = NULL;
+	struct cm_id_private *cur_cm_id_priv;
+	u64 service_id = cm_id_priv->id.service_id;
+	u64 service_mask = cm_id_priv->id.service_mask;
+
+	while (*link) {
+		parent = *link;
+		cur_cm_id_priv = rb_entry(parent, struct cm_id_private,
+					  service_node);
+		if ((cur_cm_id_priv->id.service_mask & service_id) ==
+		    (service_mask & cur_cm_id_priv->id.service_id))
+			return cm_id_priv;
+		if (service_id < cur_cm_id_priv->id.service_id)
+			link = &(*link)->rb_left;
+		else
+			link = &(*link)->rb_right;
+	}
+	rb_link_node(&cm_id_priv->service_node, parent, link);
+	rb_insert_color(&cm_id_priv->service_node, &cm.listen_service_table);
+	return NULL;
+}
+
+static struct cm_id_private * cm_find_listen(u64 service_id)
+{
+	struct rb_node *node = cm.listen_service_table.rb_node;
+	struct cm_id_private *cm_id_priv;
+
+	while (node) {
+		cm_id_priv = rb_entry(node, struct cm_id_private, service_node);
+		if ((cm_id_priv->id.service_mask & service_id) ==
+		    (cm_id_priv->id.service_mask & cm_id_priv->id.service_id))
+			return cm_id_priv;
+		if (service_id < cm_id_priv->id.service_id)
+			node = node->rb_left;
+		else
+			node = node->rb_right;
+	}
+	return NULL;
+}
+
+static struct cm_timewait_info * cm_insert_remote_id(struct cm_timewait_info
+						     *timewait_info)
+{
+	struct rb_node **link = &cm.remote_id_table.rb_node;
+	struct rb_node *parent = NULL;
+	struct cm_timewait_info *cur_timewait_info;
+	u64 remote_ca_guid = timewait_info->remote_ca_guid;
+	u32 remote_id = timewait_info->work.remote_id;
+
+	while (*link) {
+		parent = *link;
+		cur_timewait_info = rb_entry(parent, struct cm_timewait_info,
+					     remote_id_node);
+		if (remote_id < cur_timewait_info->work.remote_id)
+			link = &(*link)->rb_left;
+		else if (remote_id > cur_timewait_info->work.remote_id)
+			link = &(*link)->rb_right;
+		else if (remote_ca_guid < cur_timewait_info->remote_ca_guid)
+			link = &(*link)->rb_left;
+		else if (remote_ca_guid > cur_timewait_info->remote_ca_guid)
+			link = &(*link)->rb_right;
+		else
+			return cur_timewait_info;
+	}
+	timewait_info->inserted_remote_id = 1;
+	rb_link_node(&timewait_info->remote_id_node, parent, link);
+	rb_insert_color(&timewait_info->remote_id_node, &cm.remote_id_table);
+	return NULL;
+}
+
+static struct cm_timewait_info * cm_find_remote_id(u64 remote_ca_guid,
+						   u32 remote_id)
+{
+	struct rb_node *node = cm.remote_id_table.rb_node;
+	struct cm_timewait_info *timewait_info;
+
+	while (node) {
+		timewait_info = rb_entry(node, struct cm_timewait_info,
+					 remote_id_node);
+		if (remote_id < timewait_info->work.remote_id)
+			node = node->rb_left;
+		else if (remote_id > timewait_info->work.remote_id)
+			node = node->rb_right;
+		else if (remote_ca_guid < timewait_info->remote_ca_guid)
+			node = node->rb_left;
+		else if (remote_ca_guid > timewait_info->remote_ca_guid)
+			node = node->rb_right;
+		else
+			return timewait_info;
+	}
+	return NULL;
+}
+
+static struct cm_timewait_info * cm_insert_remote_qpn(struct cm_timewait_info
+						      *timewait_info)
+{
+	struct rb_node **link = &cm.remote_qp_table.rb_node;
+	struct rb_node *parent = NULL;
+	struct cm_timewait_info *cur_timewait_info;
+	u64 remote_ca_guid = timewait_info->remote_ca_guid;
+	u32 remote_qpn = timewait_info->remote_qpn;
+
+	while (*link) {
+		parent = *link;
+		cur_timewait_info = rb_entry(parent, struct cm_timewait_info,
+					     remote_qp_node);
+		if (remote_qpn < cur_timewait_info->remote_qpn)
+			link = &(*link)->rb_left;
+		else if (remote_qpn > cur_timewait_info->remote_qpn)
+			link = &(*link)->rb_right;
+		else if (remote_ca_guid < cur_timewait_info->remote_ca_guid)
+			link = &(*link)->rb_left;
+		else if (remote_ca_guid > cur_timewait_info->remote_ca_guid)
+			link = &(*link)->rb_right;
+		else
+			return cur_timewait_info;
+	}
+	timewait_info->inserted_remote_qp = 1;
+	rb_link_node(&timewait_info->remote_qp_node, parent, link);
+	rb_insert_color(&timewait_info->remote_qp_node, &cm.remote_qp_table);
+	return NULL;
+}
+
+static struct cm_id_private * cm_insert_remote_sidr(struct cm_id_private
+						    *cm_id_priv)
+{
+	struct rb_node **link = &cm.remote_sidr_table.rb_node;
+	struct rb_node *parent = NULL;
+	struct cm_id_private *cur_cm_id_priv;
+	union ib_gid *port_gid = &cm_id_priv->av.dgid;
+	u32 remote_id = cm_id_priv->id.remote_id;
+
+	while (*link) {
+		parent = *link;
+		cur_cm_id_priv = rb_entry(parent, struct cm_id_private,
+					  sidr_id_node);
+		if (remote_id < cur_cm_id_priv->id.remote_id)
+			link = &(*link)->rb_left;
+		else if (remote_id > cur_cm_id_priv->id.remote_id)
+			link = &(*link)->rb_right;
+		else {
+			int cmp;
+			cmp = memcmp(port_gid, &cur_cm_id_priv->av.dgid,
+				     sizeof *port_gid);
+			if (cmp < 0)
+				link = &(*link)->rb_left;
+			else if (cmp > 0)
+				link = &(*link)->rb_right;
+			else
+				return cur_cm_id_priv;
+		}
+	}
+	rb_link_node(&cm_id_priv->sidr_id_node, parent, link);
+	rb_insert_color(&cm_id_priv->sidr_id_node, &cm.remote_sidr_table);
+	return NULL;
+}
+
+static void cm_reject_sidr_req(struct cm_id_private *cm_id_priv,
+			       enum ib_cm_sidr_status status)
+{
+	struct ib_cm_sidr_rep_param param;
+
+	memset(&param, 0, sizeof param);
+	param.status = status;
+	ib_send_cm_sidr_rep(&cm_id_priv->id, &param);
+}
+
+struct ib_cm_id *ib_create_cm_id(ib_cm_handler cm_handler,
+				 void *context)
+{
+	struct cm_id_private *cm_id_priv;
+	int ret;
+
+	cm_id_priv = kmalloc(sizeof *cm_id_priv, GFP_KERNEL);
+	if (!cm_id_priv)
+		return ERR_PTR(-ENOMEM);
+
+	memset(cm_id_priv, 0, sizeof *cm_id_priv);
+	cm_id_priv->id.state = IB_CM_IDLE;
+	cm_id_priv->id.cm_handler = cm_handler;
+	cm_id_priv->id.context = context;
+	ret = cm_alloc_id(cm_id_priv);
+	if (ret)
+		goto error;
+
+	spin_lock_init(&cm_id_priv->lock);
+	init_waitqueue_head(&cm_id_priv->wait);
+	INIT_LIST_HEAD(&cm_id_priv->work_list);
+	atomic_set(&cm_id_priv->work_count, -1);
+	atomic_set(&cm_id_priv->refcount, 1);
+	return &cm_id_priv->id;
+
+error:
+	kfree(cm_id_priv);
+	return ERR_PTR(-ENOMEM);
+}
+EXPORT_SYMBOL(ib_create_cm_id);
+
+static struct cm_work * cm_dequeue_work(struct cm_id_private *cm_id_priv)
+{
+	struct cm_work *work;
+
+	if (list_empty(&cm_id_priv->work_list))
+		return NULL;
+
+	work = list_entry(cm_id_priv->work_list.next, struct cm_work, list);
+	list_del(&work->list);
+	return work;
+}
+
+static void cm_free_work(struct cm_work *work)
+{
+	if (work->mad_recv_wc)
+		ib_free_recv_mad(work->mad_recv_wc);
+	kfree(work);
+}
+
+static inline int cm_convert_to_ms(int iba_time)
+{
+	/* approximate conversion to ms from 4.096us x 2^iba_time */
+	return 1 << max(iba_time - 8, 0);
+}
+
+static void cm_cleanup_timewait(struct cm_timewait_info *timewait_info)
+{
+	unsigned long flags;
+
+	if (!timewait_info->inserted_remote_id &&
+	    !timewait_info->inserted_remote_qp)
+	    return;
+
+	spin_lock_irqsave(&cm.lock, flags);
+	if (timewait_info->inserted_remote_id) {
+		rb_erase(&timewait_info->remote_id_node, &cm.remote_id_table);
+		timewait_info->inserted_remote_id = 0;
+	}
+
+	if (timewait_info->inserted_remote_qp) {
+		rb_erase(&timewait_info->remote_qp_node, &cm.remote_qp_table);
+		timewait_info->inserted_remote_qp = 0;
+	}
+	spin_unlock_irqrestore(&cm.lock, flags);
+}
+
+static struct cm_timewait_info * cm_create_timewait_info(u32 local_id)
+{
+	struct cm_timewait_info *timewait_info;
+
+	timewait_info = kmalloc(sizeof *timewait_info, GFP_KERNEL);
+	if (!timewait_info)
+		return ERR_PTR(-ENOMEM);
+	memset(timewait_info, 0, sizeof *timewait_info);
+
+	timewait_info->work.local_id = local_id;
+	INIT_WORK(&timewait_info->work.work, cm_work_handler,
+		  &timewait_info->work);
+	timewait_info->work.cm_event.event = IB_CM_TIMEWAIT_EXIT;
+	return timewait_info;
+}
+
+static void cm_enter_timewait(struct cm_id_private *cm_id_priv)
+{
+	int wait_time;
+
+	/*
+	 * The cm_id could be destroyed by the user before we exit timewait.
+	 * To protect against this, we search for the cm_id after exiting
+	 * timewait before notifying the user that we've exited timewait.
+	 */
+	cm_id_priv->id.state = IB_CM_TIMEWAIT;
+	wait_time = cm_convert_to_ms(cm_id_priv->local_ack_timeout);
+	queue_delayed_work(cm.wq, &cm_id_priv->timewait_info->work.work,
+			   msecs_to_jiffies(wait_time));
+	cm_id_priv->timewait_info = NULL;
+}
+
+static void cm_reset_to_idle(struct cm_id_private *cm_id_priv)
+{
+	cm_id_priv->id.state = IB_CM_IDLE;
+	if (cm_id_priv->timewait_info) {
+		cm_cleanup_timewait(cm_id_priv->timewait_info);
+		kfree(cm_id_priv->timewait_info);
+		cm_id_priv->timewait_info = NULL;
+	}
+}
+
+void ib_destroy_cm_id(struct ib_cm_id *cm_id)
+{
+	struct cm_id_private *cm_id_priv;
+	struct cm_work *work;
+	unsigned long flags;
+
+	cm_id_priv = container_of(cm_id, struct cm_id_private, id);
+retest:
+	spin_lock_irqsave(&cm_id_priv->lock, flags);
+	switch (cm_id->state) {
+	case IB_CM_LISTEN:
+		cm_id->state = IB_CM_IDLE;
+		spin_unlock_irqrestore(&cm_id_priv->lock, flags);
+		spin_lock_irqsave(&cm.lock, flags);
+		rb_erase(&cm_id_priv->service_node, &cm.listen_service_table);
+		spin_unlock_irqrestore(&cm.lock, flags);
+		break;
+	case IB_CM_SIDR_REQ_SENT:
+		cm_id->state = IB_CM_IDLE;
+		ib_cancel_mad(cm_id_priv->av.port->mad_agent,
+			      (unsigned long) cm_id_priv->msg);
+		spin_unlock_irqrestore(&cm_id_priv->lock, flags);
+		break;
+	case IB_CM_SIDR_REQ_RCVD:
+		spin_unlock_irqrestore(&cm_id_priv->lock, flags);
+		cm_reject_sidr_req(cm_id_priv, IB_SIDR_REJECT);
+		break;
+	case IB_CM_REQ_SENT:
+	case IB_CM_MRA_REQ_RCVD:
+	case IB_CM_REP_SENT:
+	case IB_CM_MRA_REP_RCVD:
+		ib_cancel_mad(cm_id_priv->av.port->mad_agent,
+			      (unsigned long) cm_id_priv->msg);
+		/* Fall through */
+	case IB_CM_REQ_RCVD:
+	case IB_CM_MRA_REQ_SENT:
+	case IB_CM_REP_RCVD:
+	case IB_CM_MRA_REP_SENT:
+		spin_unlock_irqrestore(&cm_id_priv->lock, flags);
+		ib_send_cm_rej(cm_id, IB_CM_REJ_TIMEOUT,
+			       &cm_id_priv->av.port->cm_dev->ca_guid,
+			       sizeof cm_id_priv->av.port->cm_dev->ca_guid,
+			       NULL, 0);
+		break;
+	case IB_CM_ESTABLISHED:
+		spin_unlock_irqrestore(&cm_id_priv->lock, flags);
+		ib_send_cm_dreq(cm_id, NULL, 0);
+		goto retest;
+	case IB_CM_DREQ_SENT:
+		ib_cancel_mad(cm_id_priv->av.port->mad_agent,
+			      (unsigned long) cm_id_priv->msg);
+		cm_enter_timewait(cm_id_priv);
+		spin_unlock_irqrestore(&cm_id_priv->lock, flags);
+		break;
+	case IB_CM_DREQ_RCVD:
+		spin_unlock_irqrestore(&cm_id_priv->lock, flags);
+		ib_send_cm_drep(cm_id, NULL, 0);
+		break;
+	default:
+		spin_unlock_irqrestore(&cm_id_priv->lock, flags);
+		break;
+	}
+
+	cm_free_id(cm_id->local_id);
+	atomic_dec(&cm_id_priv->refcount);
+	wait_event(cm_id_priv->wait, !atomic_read(&cm_id_priv->refcount));
+	while ((work = cm_dequeue_work(cm_id_priv)) != NULL)
+		cm_free_work(work);
+	if (cm_id_priv->private_data && cm_id_priv->private_data_len)
+		kfree(cm_id_priv->private_data);
+	kfree(cm_id_priv);
+}
+EXPORT_SYMBOL(ib_destroy_cm_id);
+
+int ib_cm_listen(struct ib_cm_id *cm_id,
+		 u64 service_id,
+		 u64 service_mask)
+{
+	struct cm_id_private *cm_id_priv, *cur_cm_id_priv;
+	unsigned long flags;
+	int ret = 0;
+
+	service_mask = service_mask ? service_mask : ~0ULL;
+	service_id &= service_mask;
+	if ((service_id & IB_SERVICE_ID_AGN_MASK) == IB_CM_ASSIGN_SERVICE_ID &&
+	    (service_id != IB_CM_ASSIGN_SERVICE_ID))
+		return -EINVAL;
+
+	cm_id_priv = container_of(cm_id, struct cm_id_private, id);
+	BUG_ON(cm_id->state != IB_CM_IDLE);
+
+	cm_id->state = IB_CM_LISTEN;
+
+	spin_lock_irqsave(&cm.lock, flags);
+	if (service_id == IB_CM_ASSIGN_SERVICE_ID) {
+		cm_id->service_id = __cpu_to_be64(cm.listen_service_id++);
+		cm_id->service_mask = ~0ULL;
+	} else {
+		cm_id->service_id = service_id;
+		cm_id->service_mask = service_mask;
+	}
+	cur_cm_id_priv = cm_insert_listen(cm_id_priv);
+	spin_unlock_irqrestore(&cm.lock, flags);
+
+	if (cur_cm_id_priv) {
+		cm_id->state = IB_CM_IDLE;
+		ret = -EBUSY;
+	}
+	return ret;
+}
+EXPORT_SYMBOL(ib_cm_listen);
+
+static u64 cm_form_tid(struct cm_id_private *cm_id_priv,
+		       enum cm_msg_sequence msg_seq)
+{
+	u64 hi_tid, low_tid;
+
+	hi_tid   = ((u64) cm_id_priv->av.port->mad_agent->hi_tid) << 32;
+	low_tid  = (u64) (cm_id_priv->id.local_id | (msg_seq << 30));
+	return cpu_to_be64(hi_tid | low_tid);
+}
+
+static void cm_format_mad_hdr(struct ib_mad_hdr *hdr,
+			      enum cm_msg_attr_id attr_id, u64 tid)
+{
+	hdr->base_version  = IB_MGMT_BASE_VERSION;
+	hdr->mgmt_class	   = IB_MGMT_CLASS_CM;
+	hdr->class_version = IB_CM_CLASS_VERSION;
+	hdr->method	   = IB_MGMT_METHOD_SEND;
+	hdr->attr_id	   = attr_id;
+	hdr->tid	   = tid;
+}
+
+static void cm_format_req(struct cm_req_msg *req_msg,
+			  struct cm_id_private *cm_id_priv,
+			  struct ib_cm_req_param *param)
+{
+	cm_format_mad_hdr(&req_msg->hdr, CM_REQ_ATTR_ID,
+			  cm_form_tid(cm_id_priv, CM_MSG_SEQUENCE_REQ));
+
+	req_msg->local_comm_id = cm_id_priv->id.local_id;
+	req_msg->service_id = param->service_id;
+	req_msg->local_ca_guid = cm_id_priv->av.port->cm_dev->ca_guid;
+	cm_req_set_local_qpn(req_msg, cpu_to_be32(param->qp_num));
+	cm_req_set_resp_res(req_msg, param->responder_resources);
+	cm_req_set_init_depth(req_msg, param->initiator_depth);
+	cm_req_set_remote_resp_timeout(req_msg,
+				       param->remote_cm_response_timeout);
+	cm_req_set_qp_type(req_msg, param->qp_type);
+	cm_req_set_flow_ctrl(req_msg, param->flow_control);
+	cm_req_set_starting_psn(req_msg, cpu_to_be32(param->starting_psn));
+	cm_req_set_local_resp_timeout(req_msg,
+				      param->local_cm_response_timeout);
+	cm_req_set_retry_count(req_msg, param->retry_count);
+	req_msg->pkey = param->primary_path->pkey;
+	cm_req_set_path_mtu(req_msg, param->primary_path->mtu);
+	cm_req_set_rnr_retry_count(req_msg, param->rnr_retry_count);
+	cm_req_set_max_cm_retries(req_msg, param->max_cm_retries);
+	cm_req_set_srq(req_msg, param->srq);
+
+	req_msg->primary_local_lid = param->primary_path->slid;
+	req_msg->primary_remote_lid = param->primary_path->dlid;
+	req_msg->primary_local_gid = param->primary_path->sgid;
+	req_msg->primary_remote_gid = param->primary_path->dgid;
+	cm_req_set_primary_flow_label(req_msg, param->primary_path->flow_label);
+	cm_req_set_primary_packet_rate(req_msg, param->primary_path->rate);
+	req_msg->primary_traffic_class = param->primary_path->traffic_class;
+	req_msg->primary_hop_limit = param->primary_path->hop_limit;
+	cm_req_set_primary_sl(req_msg, param->primary_path->sl);
+	cm_req_set_primary_subnet_local(req_msg, 1); /* local only... */
+	cm_req_set_primary_local_ack_timeout(req_msg,
+		min(31, param->primary_path->packet_life_time + 1));
+
+	if (param->alternate_path) {
+		req_msg->alt_local_lid = param->alternate_path->slid;
+		req_msg->alt_remote_lid = param->alternate_path->dlid;
+		req_msg->alt_local_gid = param->alternate_path->sgid;
+		req_msg->alt_remote_gid = param->alternate_path->dgid;
+		cm_req_set_alt_flow_label(req_msg,
+					  param->alternate_path->flow_label);
+		cm_req_set_alt_packet_rate(req_msg, param->alternate_path->rate);
+		req_msg->alt_traffic_class = param->alternate_path->traffic_class;
+		req_msg->alt_hop_limit = param->alternate_path->hop_limit;
+		cm_req_set_alt_sl(req_msg, param->alternate_path->sl);
+		cm_req_set_alt_subnet_local(req_msg, 1); /* local only... */
+		cm_req_set_alt_local_ack_timeout(req_msg,
+			min(31, param->alternate_path->packet_life_time + 1));
+	}
+
+	if (param->private_data && param->private_data_len)
+		memcpy(req_msg->private_data, param->private_data,
+		       param->private_data_len);
+}
+
+static inline int cm_validate_req_param(struct ib_cm_req_param *param)
+{
+	/* peer-to-peer not supported */
+	if (param->peer_to_peer)
+		return -EINVAL;
+
+	if (!param->primary_path)
+		return -EINVAL;
+
+	if (param->qp_type != IB_QPT_RC && param->qp_type != IB_QPT_UC)
+		return -EINVAL;
+
+	if (param->private_data &&
+	    param->private_data_len > IB_CM_REQ_PRIVATE_DATA_SIZE)
+		return -EINVAL;
+
+	if (param->alternate_path &&
+	    (param->alternate_path->pkey != param->primary_path->pkey ||
+	     param->alternate_path->mtu != param->primary_path->mtu))
+		return -EINVAL;
+
+	return 0;
+}
+
+int ib_send_cm_req(struct ib_cm_id *cm_id,
+		   struct ib_cm_req_param *param)
+{
+	struct cm_id_private *cm_id_priv;
+	struct ib_send_wr *bad_send_wr;
+	struct cm_req_msg *req_msg;
+	unsigned long flags;
+	int ret;
+
+	ret = cm_validate_req_param(param);
+	if (ret)
+		return ret;
+
+	/* Verify that we're not in timewait. */
+	cm_id_priv = container_of(cm_id, struct cm_id_private, id);
+	spin_lock_irqsave(&cm_id_priv->lock, flags);
+	if (cm_id->state != IB_CM_IDLE) {
+		spin_unlock_irqrestore(&cm_id_priv->lock, flags);
+		ret = -EINVAL;
+		goto out;
+	}
+	spin_unlock_irqrestore(&cm_id_priv->lock, flags);
+
+	cm_id_priv->timewait_info = cm_create_timewait_info(cm_id_priv->
+							    id.local_id);
+	if (IS_ERR(cm_id_priv->timewait_info))
+		goto out;
+
+	ret = cm_init_av_by_path(param->primary_path, &cm_id_priv->av);
+	if (ret)
+		goto error1;
+	if (param->alternate_path) {
+		ret = cm_init_av_by_path(param->alternate_path,
+					 &cm_id_priv->alt_av);
+		if (ret)
+			goto error1;
+	}
+	cm_id->service_id = param->service_id;
+	cm_id->service_mask = ~0ULL;
+	cm_id_priv->timeout_ms = cm_convert_to_ms(
+				    param->primary_path->packet_life_time) * 2 +
+				 cm_convert_to_ms(
+				    param->remote_cm_response_timeout);
+	cm_id_priv->max_cm_retries = param->max_cm_retries;
+	cm_id_priv->initiator_depth = param->initiator_depth;
+	cm_id_priv->responder_resources = param->responder_resources;
+	cm_id_priv->retry_count = param->retry_count;
+	cm_id_priv->path_mtu = param->primary_path->mtu;
+
+	ret = cm_alloc_msg(cm_id_priv, &cm_id_priv->msg);
+	if (ret)
+		goto error1;
+
+	req_msg = (struct cm_req_msg *) cm_id_priv->msg->mad;
+	cm_format_req(req_msg, cm_id_priv, param);
+	cm_id_priv->tid = req_msg->hdr.tid;
+	cm_id_priv->msg->send_wr.wr.ud.timeout_ms = cm_id_priv->timeout_ms;
+	cm_id_priv->msg->context[1] = (void *) (unsigned long) IB_CM_REQ_SENT;
+
+	cm_id_priv->local_qpn = cm_req_get_local_qpn(req_msg);
+	cm_id_priv->rq_psn = cm_req_get_starting_psn(req_msg);
+	cm_id_priv->local_ack_timeout =
+				cm_req_get_primary_local_ack_timeout(req_msg);
+
+	spin_lock_irqsave(&cm_id_priv->lock, flags);
+	ret = ib_post_send_mad(cm_id_priv->av.port->mad_agent,
+				&cm_id_priv->msg->send_wr, &bad_send_wr);
+	if (ret) {
+		spin_unlock_irqrestore(&cm_id_priv->lock, flags);
+		goto error2;
+	}
+	BUG_ON(cm_id->state != IB_CM_IDLE);
+	cm_id->state = IB_CM_REQ_SENT;
+	spin_unlock_irqrestore(&cm_id_priv->lock, flags);
+	return 0;
+
+error2:	cm_free_msg(cm_id_priv->msg);
+error1:	kfree(cm_id_priv->timewait_info);
+out:	return ret;
+}
+EXPORT_SYMBOL(ib_send_cm_req);
+
+static int cm_issue_rej(struct cm_port *port,
+			struct ib_mad_recv_wc *mad_recv_wc,
+			enum ib_cm_rej_reason reason,
+			enum cm_msg_response msg_rejected,
+			void *ari, u8 ari_length)
+{
+	struct ib_mad_send_buf *msg = NULL;
+	struct ib_send_wr *bad_send_wr;
+	struct cm_rej_msg *rej_msg, *rcv_msg;
+	int ret;
+
+	ret = cm_alloc_response_msg(port, mad_recv_wc, &msg);
+	if (ret)
+		return ret;
+
+	/* We just need common CM header information.  Cast to any message. */
+	rcv_msg = (struct cm_rej_msg *) mad_recv_wc->recv_buf.mad;
+	rej_msg = (struct cm_rej_msg *) msg->mad;
+
+	cm_format_mad_hdr(&rej_msg->hdr, CM_REJ_ATTR_ID, rcv_msg->hdr.tid);
+	rej_msg->remote_comm_id = rcv_msg->local_comm_id;
+	rej_msg->local_comm_id = rcv_msg->remote_comm_id;
+	cm_rej_set_msg_rejected(rej_msg, msg_rejected);
+	rej_msg->reason = reason;
+
+	if (ari && ari_length) {
+		cm_rej_set_reject_info_len(rej_msg, ari_length);
+		memcpy(rej_msg->ari, ari, ari_length);
+	}
+
+	ret = ib_post_send_mad(port->mad_agent, &msg->send_wr, &bad_send_wr);
+	if (ret)
+		cm_free_msg(msg);
+
+	return ret;
+}
+
+static inline int cm_is_active_peer(u64 local_ca_guid, u64 remote_ca_guid,
+				    u32 local_qpn, u32 remote_qpn)
+{
+	return (be64_to_cpu(local_ca_guid) > be64_to_cpu(remote_ca_guid) ||
+		((local_ca_guid == remote_ca_guid) &&
+		 (be32_to_cpu(local_qpn) > be32_to_cpu(remote_qpn))));
+}
+
+static inline void cm_format_paths_from_req(struct cm_req_msg *req_msg,
+					    struct ib_sa_path_rec *primary_path,
+					    struct ib_sa_path_rec *alt_path)
+{
+	memset(primary_path, 0, sizeof *primary_path);
+	primary_path->dgid = req_msg->primary_local_gid;
+	primary_path->sgid = req_msg->primary_remote_gid;
+	primary_path->dlid = req_msg->primary_local_lid;
+	primary_path->slid = req_msg->primary_remote_lid;
+	primary_path->flow_label = cm_req_get_primary_flow_label(req_msg);
+	primary_path->hop_limit = req_msg->primary_hop_limit;
+	primary_path->traffic_class = req_msg->primary_traffic_class;
+	primary_path->reversible = 1;
+	primary_path->pkey = req_msg->pkey;
+	primary_path->sl = cm_req_get_primary_sl(req_msg);
+	primary_path->mtu_selector = IB_SA_EQ;
+	primary_path->mtu = cm_req_get_path_mtu(req_msg);
+	primary_path->rate_selector = IB_SA_EQ;
+	primary_path->rate = cm_req_get_primary_packet_rate(req_msg);
+	primary_path->packet_life_time_selector = IB_SA_EQ;
+	primary_path->packet_life_time =
+		cm_req_get_primary_local_ack_timeout(req_msg);
+	primary_path->packet_life_time -= (primary_path->packet_life_time > 0);
+
+	if (req_msg->alt_local_lid) {
+		memset(alt_path, 0, sizeof *alt_path);
+		alt_path->dgid = req_msg->alt_local_gid;
+		alt_path->sgid = req_msg->alt_remote_gid;
+		alt_path->dlid = req_msg->alt_local_lid;
+		alt_path->slid = req_msg->alt_remote_lid;
+		alt_path->flow_label = cm_req_get_alt_flow_label(req_msg);
+		alt_path->hop_limit = req_msg->alt_hop_limit;
+		alt_path->traffic_class = req_msg->alt_traffic_class;
+		alt_path->reversible = 1;
+		alt_path->pkey = req_msg->pkey;
+		alt_path->sl = cm_req_get_alt_sl(req_msg);
+		alt_path->mtu_selector = IB_SA_EQ;
+		alt_path->mtu = cm_req_get_path_mtu(req_msg);
+		alt_path->rate_selector = IB_SA_EQ;
+		alt_path->