text: /*
   * Copyright (c) 2004-2007 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.
   */
  
  #include <linux/completion.h>
  #include <linux/dma-mapping.h>
  #include <linux/device.h>
  #include <linux/module.h>
  #include <linux/err.h>
  #include <linux/idr.h>
  #include <linux/interrupt.h>
  #include <linux/random.h>
  #include <linux/rbtree.h>
  #include <linux/spinlock.h>
  #include <linux/slab.h>
  #include <linux/sysfs.h>
  #include <linux/workqueue.h>
  #include <linux/kdev_t.h>
  #include <linux/etherdevice.h>
  
  #include <rdma/ib_cache.h>
  #include <rdma/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;
  	__be32 random_id_operand;
  	struct list_head timewait_list;
  	struct workqueue_struct *wq;
  } cm;
  
  /* Counter indexes ordered by attribute ID */
  enum {
  	CM_REQ_COUNTER,
  	CM_MRA_COUNTER,
  	CM_REJ_COUNTER,
  	CM_REP_COUNTER,
  	CM_RTU_COUNTER,
  	CM_DREQ_COUNTER,
  	CM_DREP_COUNTER,
  	CM_SIDR_REQ_COUNTER,
  	CM_SIDR_REP_COUNTER,
  	CM_LAP_COUNTER,
  	CM_APR_COUNTER,
  	CM_ATTR_COUNT,
  	CM_ATTR_ID_OFFSET = 0x0010,
  };
  
  enum {
  	CM_XMIT,
  	CM_XMIT_RETRIES,
  	CM_RECV,
  	CM_RECV_DUPLICATES,
  	CM_COUNTER_GROUPS
  };
  
  static char const counter_group_names[CM_COUNTER_GROUPS]
  				     [sizeof("cm_rx_duplicates")] = {
  	"cm_tx_msgs", "cm_tx_retries",
  	"cm_rx_msgs", "cm_rx_duplicates"
  };
  
  struct cm_counter_group {
  	struct kobject obj;
  	atomic_long_t counter[CM_ATTR_COUNT];
  };
  
  struct cm_counter_attribute {
  	struct attribute attr;
  	int index;
  };
  
  #define CM_COUNTER_ATTR(_name, _index) \
  struct cm_counter_attribute cm_##_name##_counter_attr = { \
  	.attr = { .name = __stringify(_name), .mode = 0444 }, \
  	.index = _index \
  }
  
  static CM_COUNTER_ATTR(req, CM_REQ_COUNTER);
  static CM_COUNTER_ATTR(mra, CM_MRA_COUNTER);
  static CM_COUNTER_ATTR(rej, CM_REJ_COUNTER);
  static CM_COUNTER_ATTR(rep, CM_REP_COUNTER);
  static CM_COUNTER_ATTR(rtu, CM_RTU_COUNTER);
  static CM_COUNTER_ATTR(dreq, CM_DREQ_COUNTER);
  static CM_COUNTER_ATTR(drep, CM_DREP_COUNTER);
  static CM_COUNTER_ATTR(sidr_req, CM_SIDR_REQ_COUNTER);
  static CM_COUNTER_ATTR(sidr_rep, CM_SIDR_REP_COUNTER);
  static CM_COUNTER_ATTR(lap, CM_LAP_COUNTER);
  static CM_COUNTER_ATTR(apr, CM_APR_COUNTER);
  
  static struct attribute *cm_counter_default_attrs[] = {
  	&cm_req_counter_attr.attr,
  	&cm_mra_counter_attr.attr,
  	&cm_rej_counter_attr.attr,
  	&cm_rep_counter_attr.attr,
  	&cm_rtu_counter_attr.attr,
  	&cm_dreq_counter_attr.attr,
  	&cm_drep_counter_attr.attr,
  	&cm_sidr_req_counter_attr.attr,
  	&cm_sidr_rep_counter_attr.attr,
  	&cm_lap_counter_attr.attr,
  	&cm_apr_counter_attr.attr,
  	NULL
  };
  
  struct cm_port {
  	struct cm_device *cm_dev;
  	struct ib_mad_agent *mad_agent;
  	struct kobject port_obj;
  	u8 port_num;
  	struct cm_counter_group counter_group[CM_COUNTER_GROUPS];
  };
  
  struct cm_device {
  	struct list_head list;
  	struct ib_device *ib_device;
  	struct device *device;
  	u8 ack_delay;
  	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 timeout;
  	u8  valid;
  	u8  smac[ETH_ALEN];
  };
  
  struct cm_work {
  	struct delayed_work work;
  	struct list_head list;
  	struct cm_port *port;
  	struct ib_mad_recv_wc *mad_recv_wc;	/* Received MADs */
  	__be32 local_id;			/* Established / timewait */
  	__be32 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 list_head list;
  	struct rb_node remote_qp_node;
  	struct rb_node remote_id_node;
  	__be64 remote_ca_guid;
  	__be32 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;	/* Do not acquire inside cm.lock */
  	struct completion comp;
  	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;
  	struct ib_cm_compare_data *compare_data;
  
  	void *private_data;
  	__be64 tid;
  	__be32 local_qpn;
  	__be32 remote_qpn;
  	enum ib_qp_type qp_type;
  	__be32 sq_psn;
  	__be32 rq_psn;
  	int timeout_ms;
  	enum ib_mtu path_mtu;
  	__be16 pkey;
  	u8 private_data_len;
  	u8 max_cm_retries;
  	u8 peer_to_peer;
  	u8 responder_resources;
  	u8 initiator_depth;
  	u8 retry_count;
  	u8 rnr_retry_count;
  	u8 service_timeout;
  	u8 target_ack_delay;
  
  	struct list_head work_list;
  	atomic_t work_count;
  };
  
  static void cm_work_handler(struct work_struct *work);
  
  static inline void cm_deref_id(struct cm_id_private *cm_id_priv)
  {
  	if (atomic_dec_and_test(&cm_id_priv->refcount))
  		complete(&cm_id_priv->comp);
  }
  
  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, cm_id_priv->id.remote_cm_qpn,
  			       cm_id_priv->av.pkey_index,
  			       0, IB_MGMT_MAD_HDR, IB_MGMT_MAD_DATA,
  			       GFP_ATOMIC);
  	if (IS_ERR(m)) {
  		ib_destroy_ah(ah);
  		return PTR_ERR(m);
  	}
  
  	/* Timeout set by caller if response is expected. */
  	m->ah = ah;
  	m->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,
  			       0, IB_MGMT_MAD_HDR, IB_MGMT_MAD_DATA,
  			       GFP_ATOMIC);
  	if (IS_ERR(m)) {
  		ib_destroy_ah(ah);
  		return PTR_ERR(m);
  	}
  	m->ah = ah;
  	*msg = m;
  	return 0;
  }
  
  static void cm_free_msg(struct ib_mad_send_buf *msg)
  {
  	ib_destroy_ah(msg->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 = kmemdup(private_data, private_data_len, GFP_KERNEL);
  	if (!data)
  		return ERR_PTR(-ENOMEM);
  
  	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_init_av_for_response(struct cm_port *port, struct ib_wc *wc,
  				    struct ib_grh *grh, struct cm_av *av)
  {
  	av->port = port;
  	av->pkey_index = wc->pkey_index;
  	ib_init_ah_from_wc(port->cm_dev->ib_device, port->port_num, wc,
  			   grh, &av->ah_attr);
  }
  
  int ib_update_cm_av(struct ib_cm_id *id, const u8 *smac, const u8 *alt_smac)
  {
  	struct cm_id_private *cm_id_priv;
  
  	cm_id_priv = container_of(id, struct cm_id_private, id);
  
  	if (smac != NULL)
  		memcpy(cm_id_priv->av.smac, smac, sizeof(cm_id_priv->av.smac));
  
  	if (alt_smac != NULL)
  		memcpy(cm_id_priv->alt_av.smac, alt_smac,
  		       sizeof(cm_id_priv->alt_av.smac));
  
  	return 0;
  }
  EXPORT_SYMBOL(ib_update_cm_av);
  
  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->ib_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->ib_device, port->port_num,
  				  be16_to_cpu(path->pkey), &av->pkey_index);
  	if (ret)
  		return ret;
  
  	av->port = port;
  	ib_init_ah_from_path(cm_dev->ib_device, port->port_num, path,
  			     &av->ah_attr);
  	av->timeout = path->packet_life_time + 1;
  	memcpy(av->smac, path->smac, sizeof(av->smac));
  
  	av->valid = 1;
  	return 0;
  }
  
  static int cm_alloc_id(struct cm_id_private *cm_id_priv)
  {
  	unsigned long flags;
  	int id;
  
  	idr_preload(GFP_KERNEL);
  	spin_lock_irqsave(&cm.lock, flags);
  
  	id = idr_alloc_cyclic(&cm.local_id_table, cm_id_priv, 0, 0, GFP_NOWAIT);
  
  	spin_unlock_irqrestore(&cm.lock, flags);
  	idr_preload_end();
  
  	cm_id_priv->id.local_id = (__force __be32)id ^ cm.random_id_operand;
  	return id < 0 ? id : 0;
  }
  
  static void cm_free_id(__be32 local_id)
  {
  	spin_lock_irq(&cm.lock);
  	idr_remove(&cm.local_id_table,
  		   (__force int) (local_id ^ cm.random_id_operand));
  	spin_unlock_irq(&cm.lock);
  }
  
  static struct cm_id_private * cm_get_id(__be32 local_id, __be32 remote_id)
  {
  	struct cm_id_private *cm_id_priv;
  
  	cm_id_priv = idr_find(&cm.local_id_table,
  			      (__force int) (local_id ^ cm.random_id_operand));
  	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(__be32 local_id, __be32 remote_id)
  {
  	struct cm_id_private *cm_id_priv;
  
  	spin_lock_irq(&cm.lock);
  	cm_id_priv = cm_get_id(local_id, remote_id);
  	spin_unlock_irq(&cm.lock);
  
  	return cm_id_priv;
  }
  
  static void cm_mask_copy(u8 *dst, u8 *src, u8 *mask)
  {
  	int i;
  
  	for (i = 0; i < IB_CM_COMPARE_SIZE / sizeof(unsigned long); i++)
  		((unsigned long *) dst)[i] = ((unsigned long *) src)[i] &
  					     ((unsigned long *) mask)[i];
  }
  
  static int cm_compare_data(struct ib_cm_compare_data *src_data,
  			   struct ib_cm_compare_data *dst_data)
  {
  	u8 src[IB_CM_COMPARE_SIZE];
  	u8 dst[IB_CM_COMPARE_SIZE];
  
  	if (!src_data || !dst_data)
  		return 0;
  
  	cm_mask_copy(src, src_data->data, dst_data->mask);
  	cm_mask_copy(dst, dst_data->data, src_data->mask);
  	return memcmp(src, dst, IB_CM_COMPARE_SIZE);
  }
  
  static int cm_compare_private_data(u8 *private_data,
  				   struct ib_cm_compare_data *dst_data)
  {
  	u8 src[IB_CM_COMPARE_SIZE];
  
  	if (!dst_data)
  		return 0;
  
  	cm_mask_copy(src, private_data, dst_data->mask);
  	return memcmp(src, dst_data->data, IB_CM_COMPARE_SIZE);
  }
  
  /*
   * Trivial helpers to strip endian annotation and compare; the
   * endianness doesn't actually matter since we just need a stable
   * order for the RB tree.
   */
  static int be32_lt(__be32 a, __be32 b)
  {
  	return (__force u32) a < (__force u32) b;
  }
  
  static int be32_gt(__be32 a, __be32 b)
  {
  	return (__force u32) a > (__force u32) b;
  }
  
  static int be64_lt(__be64 a, __be64 b)
  {
  	return (__force u64) a < (__force u64) b;
  }
  
  static int be64_gt(__be64 a, __be64 b)
  {
  	return (__force u64) a > (__force u64) b;
  }
  
  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;
  	__be64 service_id = cm_id_priv->id.service_id;
  	__be64 service_mask = cm_id_priv->id.service_mask;
  	int data_cmp;
  
  	while (*link) {
  		parent = *link;
  		cur_cm_id_priv = rb_entry(parent, struct cm_id_private,
  					  service_node);
  		data_cmp = cm_compare_data(cm_id_priv->compare_data,
  					   cur_cm_id_priv->compare_data);
  		if ((cur_cm_id_priv->id.service_mask & service_id) ==
  		    (service_mask & cur_cm_id_priv->id.service_id) &&
  		    (cm_id_priv->id.device == cur_cm_id_priv->id.device) &&
  		    !data_cmp)
  			return cur_cm_id_priv;
  
  		if (cm_id_priv->id.device < cur_cm_id_priv->id.device)
  			link = &(*link)->rb_left;
  		else if (cm_id_priv->id.device > cur_cm_id_priv->id.device)
  			link = &(*link)->rb_right;
  		else if (be64_lt(service_id, cur_cm_id_priv->id.service_id))
  			link = &(*link)->rb_left;
  		else if (be64_gt(service_id, cur_cm_id_priv->id.service_id))
  			link = &(*link)->rb_right;
  		else if (data_cmp < 0)
  			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(struct ib_device *device,
  					     __be64 service_id,
  					     u8 *private_data)
  {
  	struct rb_node *node = cm.listen_service_table.rb_node;
  	struct cm_id_private *cm_id_priv;
  	int data_cmp;
  
  	while (node) {
  		cm_id_priv = rb_entry(node, struct cm_id_private, service_node);
  		data_cmp = cm_compare_private_data(private_data,
  						   cm_id_priv->compare_data);
  		if ((cm_id_priv->id.service_mask & service_id) ==
  		     cm_id_priv->id.service_id &&
  		    (cm_id_priv->id.device == device) && !data_cmp)
  			return cm_id_priv;
  
  		if (device < cm_id_priv->id.device)
  			node = node->rb_left;
  		else if (device > cm_id_priv->id.device)
  			node = node->rb_right;
  		else if (be64_lt(service_id, cm_id_priv->id.service_id))
  			node = node->rb_left;
  		else if (be64_gt(service_id, cm_id_priv->id.service_id))
  			node = node->rb_right;
  		else if (data_cmp < 0)
  			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;
  	__be64 remote_ca_guid = timewait_info->remote_ca_guid;
  	__be32 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 (be32_lt(remote_id, cur_timewait_info->work.remote_id))
  			link = &(*link)->rb_left;
  		else if (be32_gt(remote_id, cur_timewait_info->work.remote_id))
  			link = &(*link)->rb_right;
  		else if (be64_lt(remote_ca_guid, cur_timewait_info->remote_ca_guid))
  			link = &(*link)->rb_left;
  		else if (be64_gt(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(__be64 remote_ca_guid,
  						   __be32 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 (be32_lt(remote_id, timewait_info->work.remote_id))
  			node = node->rb_left;
  		else if (be32_gt(remote_id, timewait_info->work.remote_id))
  			node = node->rb_right;
  		else if (be64_lt(remote_ca_guid, timewait_info->remote_ca_guid))
  			node = node->rb_left;
  		else if (be64_gt(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;
  	__be64 remote_ca_guid = timewait_info->remote_ca_guid;
  	__be32 remote_qpn = timewait_info->remote_qpn;
  
  	while (*link) {
  		parent = *link;
  		cur_timewait_info = rb_entry(parent, struct cm_timewait_info,
  					     remote_qp_node);
  		if (be32_lt(remote_qpn, cur_timewait_info->remote_qpn))
  			link = &(*link)->rb_left;
  		else if (be32_gt(remote_qpn, cur_timewait_info->remote_qpn))
  			link = &(*link)->rb_right;
  		else if (be64_lt(remote_ca_guid, cur_timewait_info->remote_ca_guid))
  			link = &(*link)->rb_left;
  		else if (be64_gt(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;
  	__be32 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 (be32_lt(remote_id, cur_cm_id_priv->id.remote_id))
  			link = &(*link)->rb_left;
  		else if (be32_gt(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(struct ib_device *device,
  				 ib_cm_handler cm_handler,
  				 void *context)
  {
  	struct cm_id_private *cm_id_priv;
  	int ret;
  
  	cm_id_priv = kzalloc(sizeof *cm_id_priv, GFP_KERNEL);
  	if (!cm_id_priv)
  		return ERR_PTR(-ENOMEM);
  
  	cm_id_priv->id.state = IB_CM_IDLE;
  	cm_id_priv->id.device = device;
  	cm_id_priv->id.cm_handler = cm_handler;
  	cm_id_priv->id.context = context;
  	cm_id_priv->id.remote_cm_qpn = 1;
  	ret = cm_alloc_id(cm_id_priv);
  	if (ret)
  		goto error;
  
  	spin_lock_init(&cm_id_priv->lock);
  	init_completion(&cm_id_priv->comp);
  	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);
  }
  
  /*
   * calculate: 4.096x2^ack_timeout = 4.096x2^ack_delay + 2x4.096x2^life_time
   * Because of how ack_timeout is stored, adding one doubles the timeout.
   * To avoid large timeouts, select the max(ack_delay, life_time + 1), and
   * increment it (round up) only if the other is within 50%.
   */
  static u8 cm_ack_timeout(u8 ca_ack_delay, u8 packet_life_time)
  {
  	int ack_timeout = packet_life_time + 1;
  
  	if (ack_timeout >= ca_ack_delay)
  		ack_timeout += (ca_ack_delay >= (ack_timeout - 1));
  	else
  		ack_timeout = ca_ack_delay +
  			      (ack_timeout >= (ca_ack_delay - 1));
  
  	return min(31, ack_timeout);
  }
  
  static void cm_cleanup_timewait(struct cm_timewait_info *timewait_info)
  {
  	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;
  	}
  }
  
  static struct cm_timewait_info * cm_create_timewait_info(__be32 local_id)
  {
  	struct cm_timewait_info *timewait_info;
  
  	timewait_info = kzalloc(sizeof *timewait_info, GFP_KERNEL);
  	if (!timewait_info)
  		return ERR_PTR(-ENOMEM);
  
  	timewait_info->work.local_id = local_id;
  	INIT_DELAYED_WORK(&timewait_info->work.work, cm_work_handler);
  	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;
  	unsigned long flags;
  
  	spin_lock_irqsave(&cm.lock, flags);
  	cm_cleanup_timewait(cm_id_priv->timewait_info);
  	list_add_tail(&cm_id_priv->timewait_info->list, &cm.timewait_list);
  	spin_unlock_irqrestore(&cm.lock, flags);
  
  	/*
  	 * 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->av.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)
  {
  	unsigned long flags;
  
  	cm_id_priv->id.state = IB_CM_IDLE;
  	if (cm_id_priv->timewait_info) {
  		spin_lock_irqsave(&cm.lock, flags);
  		cm_cleanup_timewait(cm_id_priv->timewait_info);
  		spin_unlock_irqrestore(&cm.lock, flags);
  		kfree(cm_id_priv->timewait_info);
  		cm_id_priv->timewait_info = NULL;
  	}
  }
  
  static void cm_destroy_id(struct ib_cm_id *cm_id, int err)
  {
  	struct cm_id_private *cm_id_priv;
  	struct cm_work *work;
  
  	cm_id_priv = container_of(cm_id, struct cm_id_private, id);
  retest:
  	spin_lock_irq(&cm_id_priv->lock);
  	switch (cm_id->state) {
  	case IB_CM_LISTEN:
  		cm_id->state = IB_CM_IDLE;
  		spin_unlock_irq(&cm_id_priv->lock);
  		spin_lock_irq(&cm.lock);
  		rb_erase(&cm_id_priv->service_node, &cm.listen_service_table);
  		spin_unlock_irq(&cm.lock);
  		break;
  	case IB_CM_SIDR_REQ_SENT:
  		cm_id->state = IB_CM_IDLE;
  		ib_cancel_mad(cm_id_priv->av.port->mad_agent, cm_id_priv->msg);
  		spin_unlock_irq(&cm_id_priv->lock);
  		break;
  	case IB_CM_SIDR_REQ_RCVD:
  		spin_unlock_irq(&cm_id_priv->lock);
  		cm_reject_sidr_req(cm_id_priv, IB_SIDR_REJECT);
  		break;
  	case IB_CM_REQ_SENT:
  		ib_cancel_mad(cm_id_priv->av.port->mad_agent, cm_id_priv->msg);
  		spin_unlock_irq(&cm_id_priv->lock);
  		ib_send_cm_rej(cm_id, IB_CM_REJ_TIMEOUT,
  			       &cm_id_priv->id.device->node_guid,
  			       sizeof cm_id_priv->id.device->node_guid,
  			       NULL, 0);
  		break;
  	case IB_CM_REQ_RCVD:
  		if (err == -ENOMEM) {
  			/* Do not reject to allow future retries. */
  			cm_reset_to_idle(cm_id_priv);
  			spin_unlock_irq(&cm_id_priv->lock);
  		} else {
  			spin_unlock_irq(&cm_id_priv->lock);
  			ib_send_cm_rej(cm_id, IB_CM_REJ_CONSUMER_DEFINED,
  				       NULL, 0, NULL, 0);
  		}
  		break;
  	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, cm_id_priv->msg);
  		/* Fall through */
  	case IB_CM_MRA_REQ_SENT:
  	case IB_CM_REP_RCVD:
  	case IB_CM_MRA_REP_SENT:
  		spin_unlock_irq(&cm_id_priv->lock);
  		ib_send_cm_rej(cm_id, IB_CM_REJ_CONSUMER_DEFINED,
  			       NULL, 0, NULL, 0);
  		break;
  	case IB_CM_ESTABLISHED:
  		spin_unlock_irq(&cm_id_priv->lock);
  		if (cm_id_priv->qp_type == IB_QPT_XRC_TGT)
  			break;
  		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, cm_id_priv->msg);
  		cm_enter_timewait(cm_id_priv);
  		spin_unlock_irq(&cm_id_priv->lock);
  		break;
  	case IB_CM_DREQ_RCVD:
  		spin_unlock_irq(&cm_id_priv->lock);
  		ib_send_cm_drep(cm_id, NULL, 0);
  		break;
  	default:
  		spin_unlock_irq(&cm_id_priv->lock);
  		break;
  	}
  
  	cm_free_id(cm_id->local_id);
  	cm_deref_id(cm_id_priv);
  	wait_for_completion(&cm_id_priv->comp);
  	while ((work = cm_dequeue_work(cm_id_priv)) != NULL)
  		cm_free_work(work);
  	kfree(cm_id_priv->compare_data);
  	kfree(cm_id_priv->private_data);
  	kfree(cm_id_priv);
  }
  
  void ib_destroy_cm_id(struct ib_cm_id *cm_id)
  {
  	cm_destroy_id(cm_id, 0);
  }
  EXPORT_SYMBOL(ib_destroy_cm_id);
  
  int ib_cm_listen(struct ib_cm_id *cm_id, __be64 service_id, __be64 service_mask,
  		 struct ib_cm_compare_data *compare_data)
  {
  	struct cm_id_private *cm_id_priv, *cur_cm_id_priv;
  	unsigned long flags;
  	int ret = 0;
  
  	service_mask = service_mask ? service_mask : ~cpu_to_be64(0);
  	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);
  	if (cm_id->state != IB_CM_IDLE)
  		return -EINVAL;
  
  	if (compare_data) {
  		cm_id_priv->compare_data = kzalloc(sizeof *compare_data,
  						   GFP_KERNEL);
  		if (!cm_id_priv->compare_data)
  			return -ENOMEM;
  		cm_mask_copy(cm_id_priv->compare_data->data,
  			     compare_data->data, compare_data->mask);
  		memcpy(cm_id_priv->compare_data->mask, compare_data->mask,
  		       IB_CM_COMPARE_SIZE);
  	}
  
  	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 = ~cpu_to_be64(0);
  	} 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;
  		kfree(cm_id_priv->compare_data);
  		cm_id_priv->compare_data = NULL;
  		ret = -EBUSY;
  	}
  	return ret;
  }
  EXPORT_SYMBOL(ib_cm_listen);
  
  static __be64 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) ((__force u32)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,
  			      __be16 attr_id, __be64 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)
  {
  	struct ib_sa_path_rec *pri_path = param->primary_path;
  	struct ib_sa_path_rec *alt_path = param->alternate_path;
  
  	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->id.device->node_guid;
  	cm_req_set_local_qpn(req_msg, cpu_to_be32(param->qp_num));
  	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);
  	req_msg->pkey = param->primary_path->pkey;
  	cm_req_set_path_mtu(req_msg, param->primary_path->mtu);
  	cm_req_set_max_cm_retries(req_msg, param->max_cm_retries);
  
  	if (param->qp_type != IB_QPT_XRC_INI) {
  		cm_req_set_resp_res(req_msg, param->responder_resources);
  		cm_req_set_retry_count(req_msg, param->retry_count);
  		cm_req_set_rnr_retry_count(req_msg, param->rnr_retry_count);
  		cm_req_set_srq(req_msg, param->srq);
  	}
  
  	if (pri_path->hop_limit <= 1) {
  		req_msg->primary_local_lid = pri_path->slid;
  		req_msg->primary_remote_lid = pri_path->dlid;
  	} else {
  		/* Work-around until there's a way to obtain remote LID info */
  		req_msg->primary_local_lid = IB_LID_PERMISSIVE;
  		req_msg->primary_remote_lid = IB_LID_PERMISSIVE;
  	}
  	req_msg->primary_local_gid = pri_path->sgid;
  	req_msg->primary_remote_gid = pri_path->dgid;
  	cm_req_set_primary_flow_label(req_msg, pri_path->flow_label);
  	cm_req_set_primary_packet_rate(req_msg, pri_path->rate);
  	req_msg->primary_traffic_class = pri_path->traffic_class;
  	req_msg->primary_hop_limit = pri_path->hop_limit;
  	cm_req_set_primary_sl(req_msg, pri_path->sl);
  	cm_req_set_primary_subnet_local(req_msg, (pri_path->hop_limit <= 1));
  	cm_req_set_primary_local_ack_timeout(req_msg,
  		cm_ack_timeout(cm_id_priv->av.port->cm_dev->ack_delay,
  			       pri_path->packet_life_time));
  
  	if (alt_path) {
  		if (alt_path->hop_limit <= 1) {
  			req_msg->alt_local_lid = alt_path->slid;
  			req_msg->alt_remote_lid = alt_path->dlid;
  		} else {
  			req_msg->alt_local_lid = IB_LID_PERMISSIVE;
  			req_msg->alt_remote_lid = IB_LID_PERMISSIVE;
  		}
  		req_msg->alt_local_gid = alt_path->sgid;
  		req_msg->alt_remote_gid = alt_path->dgid;
  		cm_req_set_alt_flow_label(req_msg,
  					  alt_path->flow_label);
  		cm_req_set_alt_packet_rate(req_msg, alt_path->rate);
  		req_msg->alt_traffic_class = alt_path->traffic_class;
  		req_msg->alt_hop_limit = alt_path->hop_limit;
  		cm_req_set_alt_sl(req_msg, alt_path->sl);
  		cm_req_set_alt_subnet_local(req_msg, (alt_path->hop_limit <= 1));
  		cm_req_set_alt_local_ack_timeout(req_msg,
  			cm_ack_timeout(cm_id_priv->av.port->cm_dev->ack_delay,
  				       alt_path->packet_life_time));
  	}
  
  	if (param->private_data && param->private_data_len)
  		memcpy(req_msg->private_data, param->private_data,
  		       param->private_data_len);
  }
  
  static 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 &&
  	    param->qp_type != IB_QPT_XRC_INI)
  		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 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)) {
  		ret = PTR_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 = ~cpu_to_be64(0);
  	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;
  	cm_id_priv->pkey = param->primary_path->pkey;
  	cm_id_priv->qp_type = param->qp_type;
  
  	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->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);
  
  	spin_lock_irqsave(&cm_id_priv->lock, flags);
  	ret = ib_post_send_mad(cm_id_priv->msg, NULL);
  	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 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 = cpu_to_be16(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(msg, NULL);
  	if (ret)
  		cm_free_msg(msg);
  
  	return ret;
  }
  
  static inline int cm_is_active_peer(__be64 local_ca_guid, __be64 remote_ca_guid,
  				    __be32 local_qpn, __be32 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 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->rate = cm_req_get_alt_packet_rate(req_msg);
  		alt_path->packet_life_time_selector = IB_SA_EQ;
  		alt_path->packet_life_time =
  			cm_req_get_alt_local_ack_timeout(req_msg);
  		alt_path->packet_life_time -= (alt_path->packet_life_time > 0);
  	}
  }
  
  static void cm_format_req_event(struct cm_work *work,
  				struct cm_id_private *cm_id_priv,
  				struct ib_cm_id *listen_id)
  {
  	struct cm_req_msg *req_msg;
  	struct ib_cm_req_event_param *param;
  
  	req_msg = (struct cm_req_msg *)work->mad_recv_wc->recv_buf.mad;
  	param = &work->cm_event.param.req_rcvd;
  	param->listen_id = listen_id;
  	param->port = cm_id_priv->av.port->port_num;
  	param->primary_path = &work->path[0];
  	if (req_msg->alt_local_lid)
  		param->alternate_path = &work->path[1];
  	else
  		param->alternate_path = NULL;
  	param->remote_ca_guid = req_msg->local_ca_guid;
  	param->remote_qkey = be32_to_cpu(req_msg->local_qkey);
  	param->remote_qpn = be32_to_cpu(cm_req_get_local_qpn(req_msg));
  	param->qp_type = cm_req_get_qp_type(req_msg);
  	param->starting_psn = be32_to_cpu(cm_req_get_starting_psn(req_msg));
  	param->responder_resources = cm_req_get_init_depth(req_msg);
  	param->initiator_depth = cm_req_get_resp_res(req_msg);
  	param->local_cm_response_timeout =
  					cm_req_get_remote_resp_timeout(req_msg);
  	param->flow_control = cm_req_get_flow_ctrl(req_msg);
  	param->remote_cm_response_timeout =
  					cm_req_get_local_resp_timeout(req_msg);
  	param->retry_count = cm_req_get_retry_count(req_msg);
  	param->rnr_retry_count = cm_req_get_rnr_retry_count(req_msg);
  	param->srq = cm_req_get_srq(req_msg);
  	work->cm_event.private_data = &req_msg->private_data;
  }
  
  static void cm_process_work(struct cm_id_private *cm_id_priv,
  			    struct cm_work *work)
  {
  	int ret;
  
  	/* We will typically only have the current event to report. */
  	ret = cm_id_priv->id.cm_handler(&cm_id_priv->id, &work->cm_event);
  	cm_free_work(work);
  
  	while (!ret && !atomic_add_negative(-1, &cm_id_priv->work_count)) {
  		spin_lock_irq(&cm_id_priv->lock);
  		work = cm_dequeue_work(cm_id_priv);
  		spin_unlock_irq(&cm_id_priv->lock);
  		BUG_ON(!work);
  		ret = cm_id_priv->id.cm_handler(&cm_id_priv->id,
  						&work->cm_event);
  		cm_free_work(work);
  	}
  	cm_deref_id(cm_id_priv);
  	if (ret)
  		cm_destroy_id(&cm_id_priv->id, ret);
  }
  
  static void cm_format_mra(struct cm_mra_msg *mra_msg,
  			  struct cm_id_private *cm_id_priv,
  			  enum cm_msg_response msg_mraed, u8 service_timeout,
  			  const void *private_data, u8 private_data_len)
  {
  	cm_format_mad_hdr(&mra_msg->hdr, CM_MRA_ATTR_ID, cm_id_priv->tid);
  	cm_mra_set_msg_mraed(mra_msg, msg_mraed);
  	mra_msg->local_comm_id = cm_id_priv->id.local_id;
  	mra_msg->remote_comm_id = cm_id_priv->id.remote_id;
  	cm_mra_set_service_timeout(mra_msg, service_timeout);
  
  	if (private_data && private_data_len)
  		memcpy(mra_msg->private_data, private_data, private_data_len);
  }
  
  static void cm_format_rej(struct cm_rej_msg *rej_msg,
  			  struct cm_id_private *cm_id_priv,
  			  enum ib_cm_rej_reason reason,
  			  void *ari,
  			  u8 ari_length,
  			  const void *private_data,
  			  u8 private_data_len)
  {
  	cm_format_mad_hdr(&rej_msg->hdr, CM_REJ_ATTR_ID, cm_id_priv->tid);
  	rej_msg->remote_comm_id = cm_id_priv->id.remote_id;
  
  	switch(cm_id_priv->id.state) {
  	case IB_CM_REQ_RCVD:
  		rej_msg->local_comm_id = 0;
  		cm_rej_set_msg_rejected(rej_msg, CM_MSG_RESPONSE_REQ);
  		break;
  	case IB_CM_MRA_REQ_SENT:
  		rej_msg->local_comm_id = cm_id_priv->id.local_id;
  		cm_rej_set_msg_rejected(rej_msg, CM_MSG_RESPONSE_REQ);
  		break;
  	case IB_CM_REP_RCVD:
  	case IB_CM_MRA_REP_SENT:
  		rej_msg->local_comm_id = cm_id_priv->id.local_id;
  		cm_rej_set_msg_rejected(rej_msg, CM_MSG_RESPONSE_REP);
  		break;
  	default:
  		rej_msg->local_comm_id = cm_id_priv->id.local_id;
  		cm_rej_set_msg_rejected(rej_msg, CM_MSG_RESPONSE_OTHER);
  		break;
  	}
  
  	rej_msg->reason = cpu_to_be16(reason);
  	if (ari && ari_length) {
  		cm_rej_set_reject_info_len(rej_msg, ari_length);
  		memcpy(rej_msg->ari, ari, ari_length);
  	}
  
  	if (private_data && private_data_len)
  		memcpy(rej_msg->private_data, private_data, private_data_len);
  }
  
  static void cm_dup_req_handler(struct cm_work *work,
  			       struct cm_id_private *cm_id_priv)
  {
  	struct ib_mad_send_buf *msg = NULL;
  	int ret;
  
  	atomic_long_inc(&work->port->counter_group[CM_RECV_DUPLICATES].
  			counter[CM_REQ_COUNTER]);
  
  	/* Quick state check to discard duplicate REQs. */
  	if (cm_id_priv->id.state == IB_CM_REQ_RCVD)
  		return;
  
  	ret = cm_alloc_response_msg(work->port, work->mad_recv_wc, &msg);
  	if (ret)
  		return;
  
  	spin_lock_irq(&cm_id_priv->lock);
  	switch (cm_id_priv->id.state) {
  	case IB_CM_MRA_REQ_SENT:
  		cm_format_mra((struct cm_mra_msg *) msg->mad, cm_id_priv,
  			      CM_MSG_RESPONSE_REQ, cm_id_priv->service_timeout,
  			      cm_id_priv->private_data,
  			      cm_id_priv->private_data_len);
  		break;
  	case IB_CM_TIMEWAIT:
  		cm_format_rej((struct cm_rej_msg *) msg->mad, cm_id_priv,
  			      IB_CM_REJ_STALE_CONN, NULL, 0, NULL, 0);
  		break;
  	default:
  		goto unlock;
  	}
  	spin_unlock_irq(&cm_id_priv->lock);
  
  	ret = ib_post_send_mad(msg, NULL);
  	if (ret)
  		goto free;
  	return;
  
  unlock:	spin_unlock_irq(&cm_id_priv->lock);
  free:	cm_free_msg(msg);
  }
  
  static struct cm_id_private * cm_match_req(struct cm_work *work,
  					   struct cm_id_private *cm_id_priv)
  {
  	struct cm_id_private *listen_cm_id_priv, *cur_cm_id_priv;
  	struct cm_timewait_info *timewait_info;
  	struct cm_req_msg *req_msg;
  
  	req_msg = (struct cm_req_msg *)work->mad_recv_wc->recv_buf.mad;
  
  	/* Check for possible duplicate REQ. */
  	spin_lock_irq(&cm.lock);
  	timewait_info = cm_insert_remote_id(cm_id_priv->timewait_info);
  	if (timewait_info) {
  		cur_cm_id_priv = cm_get_id(timewait_info->work.local_id,
  					   timewait_info->work.remote_id);
  		spin_unlock_irq(&cm.lock);
  		if (cur_cm_id_priv) {
  			cm_dup_req_handler(work, cur_cm_id_priv);
  			cm_deref_id(cur_cm_id_priv);
  		}
  		return NULL;
  	}
  
  	/* Check for stale connections. */
  	timewait_info = cm_insert_remote_qpn(cm_id_priv->timewait_info);
  	if (timewait_info) {
  		cm_cleanup_timewait(cm_id_priv->timewait_info);
  		spin_unlock_irq(&cm.lock);
  		cm_issue_rej(work->port, work->mad_recv_wc,
  			     IB_CM_REJ_STALE_CONN, CM_MSG_RESPONSE_REQ,
  			     NULL, 0);
  		return NULL;
  	}
  
  	/* Find matching listen request. */
  	listen_cm_id_priv = cm_find_listen(cm_id_priv->id.device,
  					   req_msg->service_id,
  					   req_msg->private_data);
  	if (!listen_cm_id_priv) {
  		cm_cleanup_timewait(cm_id_priv->timewait_info);
  		spin_unlock_irq(&cm.lock);
  		cm_issue_rej(work->port, work->mad_recv_wc,
  			     IB_CM_REJ_INVALID_SERVICE_ID, CM_MSG_RESPONSE_REQ,
  			     NULL, 0);
  		goto out;
  	}
  	atomic_inc(&listen_cm_id_priv->refcount);
  	atomic_inc(&cm_id_priv->refcount);
  	cm_id_priv->id.state = IB_CM_REQ_RCVD;
  	atomic_inc(&cm_id_priv->work_count);
  	spin_unlock_irq(&cm.lock);
  out:
  	return listen_cm_id_priv;
  }
  
  /*
   * Work-around for inter-subnet connections.  If the LIDs are permissive,
   * we need to override the LID/SL data in the REQ with the LID information
   * in the work completion.
   */
  static void cm_process_routed_req(struct cm_req_msg *req_msg, struct ib_wc *wc)
  {
  	if (!cm_req_get_primary_subnet_local(req_msg)) {
  		if (req_msg->primary_local_lid == IB_LID_PERMISSIVE) {
  			req_msg->primary_local_lid = cpu_to_be16(wc->slid);
  			cm_req_set_primary_sl(req_msg, wc->sl);
  		}
  
  		if (req_msg->primary_remote_lid == IB_LID_PERMISSIVE)
  			req_msg->primary_remote_lid = cpu_to_be16(wc->dlid_path_bits);
  	}
  
  	if (!cm_req_get_alt_subnet_local(req_msg)) {
  		if (req_msg->alt_local_lid == IB_LID_PERMISSIVE) {
  			req_msg->alt_local_lid = cpu_to_be16(wc->slid);
  			cm_req_set_alt_sl(req_msg, wc->sl);
  		}
  
  		if (req_msg->alt_remote_lid == IB_LID_PERMISSIVE)
  			req_msg->alt_remote_lid = cpu_to_be16(wc->dlid_path_bits);
  	}
  }
  
  static int cm_req_handler(struct cm_work *work)
  {
  	struct ib_cm_id *cm_id;
  	struct cm_id_private *cm_id_priv, *listen_cm_id_priv;
  	struct cm_req_msg *req_msg;
  	int ret;
  
  	req_msg = (struct cm_req_msg *)work->mad_recv_wc->recv_buf.mad;
  
  	cm_id = ib_create_cm_id(work->port->cm_dev->ib_device, NULL, NULL);
  	if (IS_ERR(cm_id))
  		return PTR_ERR(cm_id);
  
  	cm_id_priv = container_of(cm_id, struct cm_id_private, id);
  	cm_id_priv->id.remote_id = req_msg->local_comm_id;
  	cm_init_av_for_response(work->port, work->mad_recv_wc->wc,
  				work->mad_recv_wc->recv_buf.grh,
  				&cm_id_priv->av);
  	cm_id_priv->timewait_info = cm_create_timewait_info(cm_id_priv->
  							    id.local_id);
  	if (IS_ERR(cm_id_priv->timewait_info)) {
  		ret = PTR_ERR(cm_id_priv->timewait_info);
  		goto destroy;
  	}
  	cm_id_priv->timewait_info->work.remote_id = req_msg->local_comm_id;
  	cm_id_priv->timewait_info->remote_ca_guid = req_msg->local_ca_guid;
  	cm_id_priv->timewait_info->remote_qpn = cm_req_get_local_qpn(req_msg);
  
  	listen_cm_id_priv = cm_match_req(work, cm_id_priv);
  	if (!listen_cm_id_priv) {
  		ret = -EINVAL;
  		kfree(cm_id_priv->timewait_info);
  		goto destroy;
  	}
  
  	cm_id_priv->id.cm_handler = listen_cm_id_priv->id.cm_handler;
  	cm_id_priv->id.context = listen_cm_id_priv->id.context;
  	cm_id_priv->id.service_id = req_msg->service_id;
  	cm_id_priv->id.service_mask = ~cpu_to_be64(0);
  
  	cm_process_routed_req(req_msg, work->mad_recv_wc->wc);
  	cm_format_paths_from_req(req_msg, &work->path[0], &work->path[1]);
  
  	memcpy(work->path[0].dmac, cm_id_priv->av.ah_attr.dmac, ETH_ALEN);
  	work->path[0].vlan_id = cm_id_priv->av.ah_attr.vlan_id;
  	ret = cm_init_av_by_path(&work->path[0], &cm_id_priv->av);
  	if (ret) {
  		ib_get_cached_gid(work->port->cm_dev->ib_device,
  				  work->port->port_num, 0, &work->path[0].sgid);
  		ib_send_cm_rej(cm_id, IB_CM_REJ_INVALID_GID,
  			       &work->path[0].sgid, sizeof work->path[0].sgid,
  			       NULL, 0);
  		goto rejected;
  	}
  	if (req_msg->alt_local_lid) {
  		ret = cm_init_av_by_path(&work->path[1], &cm_id_priv->alt_av);
  		if (ret) {
  			ib_send_cm_rej(cm_id, IB_CM_REJ_INVALID_ALT_GID,
  				       &work->path[0].sgid,
  				       sizeof work->path[0].sgid, NULL, 0);
  			goto rejected;
  		}
  	}
  	cm_id_priv->tid = req_msg->hdr.tid;
  	cm_id_priv->timeout_ms = cm_convert_to_ms(
  					cm_req_get_local_resp_timeout(req_msg));
  	cm_id_priv->max_cm_retries = cm_req_get_max_cm_retries(req_msg);
  	cm_id_priv->remote_qpn = cm_req_get_local_qpn(req_msg);
  	cm_id_priv->initiator_depth = cm_req_get_resp_res(req_msg);
  	cm_id_priv->responder_resources = cm_req_get_init_depth(req_msg);
  	cm_id_priv->path_mtu = cm_req_get_path_mtu(req_msg);
  	cm_id_priv->pkey = req_msg->pkey;
  	cm_id_priv->sq_psn = cm_req_get_starting_psn(req_msg);
  	cm_id_priv->retry_count = cm_req_get_retry_count(req_msg);
  	cm_id_priv->rnr_retry_count = cm_req_get_rnr_retry_count(req_msg);
  	cm_id_priv->qp_type = cm_req_get_qp_type(req_msg);
  
  	cm_format_req_event(work, cm_id_priv, &listen_cm_id_priv->id);
  	cm_process_work(cm_id_priv, work);
  	cm_deref_id(listen_cm_id_priv);
  	return 0;
  
  rejected:
  	atomic_dec(&cm_id_priv->refcount);
  	cm_deref_id(listen_cm_id_priv);
  destroy:
  	ib_destroy_cm_id(cm_id);
  	return ret;
  }
  
  static void cm_format_rep(struct cm_rep_msg *rep_msg,
  			  struct cm_id_private *cm_id_priv,
  			  struct ib_cm_rep_param *param)
  {
  	cm_format_mad_hdr(&rep_msg->hdr, CM_REP_ATTR_ID, cm_id_priv->tid);
  	rep_msg->local_comm_id = cm_id_priv->id.local_id;
  	rep_msg->remote_comm_id = cm_id_priv->id.remote_id;
  	cm_rep_set_starting_psn(rep_msg, cpu_to_be32(param->starting_psn));
  	rep_msg->resp_resources = param->responder_resources;
  	cm_rep_set_target_ack_delay(rep_msg,
  				    cm_id_priv->av.port->cm_dev->ack_delay);
  	cm_rep_set_failover(rep_msg, param->failover_accepted);
  	cm_rep_set_rnr_retry_count(rep_msg, param->rnr_retry_count);
  	rep_msg->local_ca_guid = cm_id_priv->id.device->node_guid;
  
  	if (cm_id_priv->qp_type != IB_QPT_XRC_TGT) {
  		rep_msg->initiator_depth = param->initiator_depth;
  		cm_rep_set_flow_ctrl(rep_msg, param->flow_control);
  		cm_rep_set_srq(rep_msg, param->srq);
  		cm_rep_set_local_qpn(rep_msg, cpu_to_be32(param->qp_num));
  	} else {
  		cm_rep_set_srq(rep_msg, 1);
  		cm_rep_set_local_eecn(rep_msg, cpu_to_be32(param->qp_num));
  	}
  
  	if (param->private_data && param->private_data_len)
  		memcpy(rep_msg->private_data, param->private_data,
  		       param->private_data_len);
  }
  
  int ib_send_cm_rep(struct ib_cm_id *cm_id,
  		   struct ib_cm_rep_param *param)
  {
  	struct cm_id_private *cm_id_priv;
  	struct ib_mad_send_buf *msg;
  	struct cm_rep_msg *rep_msg;
  	unsigned long flags;
  	int ret;
  
  	if (param->private_data &&
  	    param->private_data_len > IB_CM_REP_PRIVATE_DATA_SIZE)
  		return -EINVAL;
  
  	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_REQ_RCVD &&
  	    cm_id->state != IB_CM_MRA_REQ_SENT) {
  		ret = -EINVAL;
  		goto out;
  	}
  
  	ret = cm_alloc_msg(cm_id_priv, &msg);
  	if (ret)
  		goto out;
  
  	rep_msg = (struct cm_rep_msg *) msg->mad;
  	cm_format_rep(rep_msg, cm_id_priv, param);
  	msg->timeout_ms = cm_id_priv->timeout_ms;
  	msg->context[1] = (void *) (unsigned long) IB_CM_REP_SENT;
  
  	ret = ib_post_send_mad(msg, NULL);
  	if (ret) {
  		spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  		cm_free_msg(msg);
  		return ret;
  	}
  
  	cm_id->state = IB_CM_REP_SENT;
  	cm_id_priv->msg = msg;
  	cm_id_priv->initiator_depth = param->initiator_depth;
  	cm_id_priv->responder_resources = param->responder_resources;
  	cm_id_priv->rq_psn = cm_rep_get_starting_psn(rep_msg);
  	cm_id_priv->local_qpn = cpu_to_be32(param->qp_num & 0xFFFFFF);
  
  out:	spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  	return ret;
  }
  EXPORT_SYMBOL(ib_send_cm_rep);
  
  static void cm_format_rtu(struct cm_rtu_msg *rtu_msg,
  			  struct cm_id_private *cm_id_priv,
  			  const void *private_data,
  			  u8 private_data_len)
  {
  	cm_format_mad_hdr(&rtu_msg->hdr, CM_RTU_ATTR_ID, cm_id_priv->tid);
  	rtu_msg->local_comm_id = cm_id_priv->id.local_id;
  	rtu_msg->remote_comm_id = cm_id_priv->id.remote_id;
  
  	if (private_data && private_data_len)
  		memcpy(rtu_msg->private_data, private_data, private_data_len);
  }
  
  int ib_send_cm_rtu(struct ib_cm_id *cm_id,
  		   const void *private_data,
  		   u8 private_data_len)
  {
  	struct cm_id_private *cm_id_priv;
  	struct ib_mad_send_buf *msg;
  	unsigned long flags;
  	void *data;
  	int ret;
  
  	if (private_data && private_data_len > IB_CM_RTU_PRIVATE_DATA_SIZE)
  		return -EINVAL;
  
  	data = cm_copy_private_data(private_data, private_data_len);
  	if (IS_ERR(data))
  		return PTR_ERR(data);
  
  	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_REP_RCVD &&
  	    cm_id->state != IB_CM_MRA_REP_SENT) {
  		ret = -EINVAL;
  		goto error;
  	}
  
  	ret = cm_alloc_msg(cm_id_priv, &msg);
  	if (ret)
  		goto error;
  
  	cm_format_rtu((struct cm_rtu_msg *) msg->mad, cm_id_priv,
  		      private_data, private_data_len);
  
  	ret = ib_post_send_mad(msg, NULL);
  	if (ret) {
  		spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  		cm_free_msg(msg);
  		kfree(data);
  		return ret;
  	}
  
  	cm_id->state = IB_CM_ESTABLISHED;
  	cm_set_private_data(cm_id_priv, data, private_data_len);
  	spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  	return 0;
  
  error:	spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  	kfree(data);
  	return ret;
  }
  EXPORT_SYMBOL(ib_send_cm_rtu);
  
  static void cm_format_rep_event(struct cm_work *work, enum ib_qp_type qp_type)
  {
  	struct cm_rep_msg *rep_msg;
  	struct ib_cm_rep_event_param *param;
  
  	rep_msg = (struct cm_rep_msg *)work->mad_recv_wc->recv_buf.mad;
  	param = &work->cm_event.param.rep_rcvd;
  	param->remote_ca_guid = rep_msg->local_ca_guid;
  	param->remote_qkey = be32_to_cpu(rep_msg->local_qkey);
  	param->remote_qpn = be32_to_cpu(cm_rep_get_qpn(rep_msg, qp_type));
  	param->starting_psn = be32_to_cpu(cm_rep_get_starting_psn(rep_msg));
  	param->responder_resources = rep_msg->initiator_depth;
  	param->initiator_depth = rep_msg->resp_resources;
  	param->target_ack_delay = cm_rep_get_target_ack_delay(rep_msg);
  	param->failover_accepted = cm_rep_get_failover(rep_msg);
  	param->flow_control = cm_rep_get_flow_ctrl(rep_msg);
  	param->rnr_retry_count = cm_rep_get_rnr_retry_count(rep_msg);
  	param->srq = cm_rep_get_srq(rep_msg);
  	work->cm_event.private_data = &rep_msg->private_data;
  }
  
  static void cm_dup_rep_handler(struct cm_work *work)
  {
  	struct cm_id_private *cm_id_priv;
  	struct cm_rep_msg *rep_msg;
  	struct ib_mad_send_buf *msg = NULL;
  	int ret;
  
  	rep_msg = (struct cm_rep_msg *) work->mad_recv_wc->recv_buf.mad;
  	cm_id_priv = cm_acquire_id(rep_msg->remote_comm_id,
  				   rep_msg->local_comm_id);
  	if (!cm_id_priv)
  		return;
  
  	atomic_long_inc(&work->port->counter_group[CM_RECV_DUPLICATES].
  			counter[CM_REP_COUNTER]);
  	ret = cm_alloc_response_msg(work->port, work->mad_recv_wc, &msg);
  	if (ret)
  		goto deref;
  
  	spin_lock_irq(&cm_id_priv->lock);
  	if (cm_id_priv->id.state == IB_CM_ESTABLISHED)
  		cm_format_rtu((struct cm_rtu_msg *) msg->mad, cm_id_priv,
  			      cm_id_priv->private_data,
  			      cm_id_priv->private_data_len);
  	else if (cm_id_priv->id.state == IB_CM_MRA_REP_SENT)
  		cm_format_mra((struct cm_mra_msg *) msg->mad, cm_id_priv,
  			      CM_MSG_RESPONSE_REP, cm_id_priv->service_timeout,
  			      cm_id_priv->private_data,
  			      cm_id_priv->private_data_len);
  	else
  		goto unlock;
  	spin_unlock_irq(&cm_id_priv->lock);
  
  	ret = ib_post_send_mad(msg, NULL);
  	if (ret)
  		goto free;
  	goto deref;
  
  unlock:	spin_unlock_irq(&cm_id_priv->lock);
  free:	cm_free_msg(msg);
  deref:	cm_deref_id(cm_id_priv);
  }
  
  static int cm_rep_handler(struct cm_work *work)
  {
  	struct cm_id_private *cm_id_priv;
  	struct cm_rep_msg *rep_msg;
  	int ret;
  
  	rep_msg = (struct cm_rep_msg *)work->mad_recv_wc->recv_buf.mad;
  	cm_id_priv = cm_acquire_id(rep_msg->remote_comm_id, 0);
  	if (!cm_id_priv) {
  		cm_dup_rep_handler(work);
  		return -EINVAL;
  	}
  
  	cm_format_rep_event(work, cm_id_priv->qp_type);
  
  	spin_lock_irq(&cm_id_priv->lock);
  	switch (cm_id_priv->id.state) {
  	case IB_CM_REQ_SENT:
  	case IB_CM_MRA_REQ_RCVD:
  		break;
  	default:
  		spin_unlock_irq(&cm_id_priv->lock);
  		ret = -EINVAL;
  		goto error;
  	}
  
  	cm_id_priv->timewait_info->work.remote_id = rep_msg->local_comm_id;
  	cm_id_priv->timewait_info->remote_ca_guid = rep_msg->local_ca_guid;
  	cm_id_priv->timewait_info->remote_qpn = cm_rep_get_qpn(rep_msg, cm_id_priv->qp_type);
  
  	spin_lock(&cm.lock);
  	/* Check for duplicate REP. */
  	if (cm_insert_remote_id(cm_id_priv->timewait_info)) {
  		spin_unlock(&cm.lock);
  		spin_unlock_irq(&cm_id_priv->lock);
  		ret = -EINVAL;
  		goto error;
  	}
  	/* Check for a stale connection. */
  	if (cm_insert_remote_qpn(cm_id_priv->timewait_info)) {
  		rb_erase(&cm_id_priv->timewait_info->remote_id_node,
  			 &cm.remote_id_table);
  		cm_id_priv->timewait_info->inserted_remote_id = 0;
  		spin_unlock(&cm.lock);
  		spin_unlock_irq(&cm_id_priv->lock);
  		cm_issue_rej(work->port, work->mad_recv_wc,
  			     IB_CM_REJ_STALE_CONN, CM_MSG_RESPONSE_REP,
  			     NULL, 0);
  		ret = -EINVAL;
  		goto error;
  	}
  	spin_unlock(&cm.lock);
  
  	cm_id_priv->id.state = IB_CM_REP_RCVD;
  	cm_id_priv->id.remote_id = rep_msg->local_comm_id;
  	cm_id_priv->remote_qpn = cm_rep_get_qpn(rep_msg, cm_id_priv->qp_type);
  	cm_id_priv->initiator_depth = rep_msg->resp_resources;
  	cm_id_priv->responder_resources = rep_msg->initiator_depth;
  	cm_id_priv->sq_psn = cm_rep_get_starting_psn(rep_msg);
  	cm_id_priv->rnr_retry_count = cm_rep_get_rnr_retry_count(rep_msg);
  	cm_id_priv->target_ack_delay = cm_rep_get_target_ack_delay(rep_msg);
  	cm_id_priv->av.timeout =
  			cm_ack_timeout(cm_id_priv->target_ack_delay,
  				       cm_id_priv->av.timeout - 1);
  	cm_id_priv->alt_av.timeout =
  			cm_ack_timeout(cm_id_priv->target_ack_delay,
  				       cm_id_priv->alt_av.timeout - 1);
  
  	/* todo: handle peer_to_peer */
  
  	ib_cancel_mad(cm_id_priv->av.port->mad_agent, cm_id_priv->msg);
  	ret = atomic_inc_and_test(&cm_id_priv->work_count);
  	if (!ret)
  		list_add_tail(&work->list, &cm_id_priv->work_list);
  	spin_unlock_irq(&cm_id_priv->lock);
  
  	if (ret)
  		cm_process_work(cm_id_priv, work);
  	else
  		cm_deref_id(cm_id_priv);
  	return 0;
  
  error:
  	cm_deref_id(cm_id_priv);
  	return ret;
  }
  
  static int cm_establish_handler(struct cm_work *work)
  {
  	struct cm_id_private *cm_id_priv;
  	int ret;
  
  	/* See comment in cm_establish about lookup. */
  	cm_id_priv = cm_acquire_id(work->local_id, work->remote_id);
  	if (!cm_id_priv)
  		return -EINVAL;
  
  	spin_lock_irq(&cm_id_priv->lock);
  	if (cm_id_priv->id.state != IB_CM_ESTABLISHED) {
  		spin_unlock_irq(&cm_id_priv->lock);
  		goto out;
  	}
  
  	ib_cancel_mad(cm_id_priv->av.port->mad_agent, cm_id_priv->msg);
  	ret = atomic_inc_and_test(&cm_id_priv->work_count);
  	if (!ret)
  		list_add_tail(&work->list, &cm_id_priv->work_list);
  	spin_unlock_irq(&cm_id_priv->lock);
  
  	if (ret)
  		cm_process_work(cm_id_priv, work);
  	else
  		cm_deref_id(cm_id_priv);
  	return 0;
  out:
  	cm_deref_id(cm_id_priv);
  	return -EINVAL;
  }
  
  static int cm_rtu_handler(struct cm_work *work)
  {
  	struct cm_id_private *cm_id_priv;
  	struct cm_rtu_msg *rtu_msg;
  	int ret;
  
  	rtu_msg = (struct cm_rtu_msg *)work->mad_recv_wc->recv_buf.mad;
  	cm_id_priv = cm_acquire_id(rtu_msg->remote_comm_id,
  				   rtu_msg->local_comm_id);
  	if (!cm_id_priv)
  		return -EINVAL;
  
  	work->cm_event.private_data = &rtu_msg->private_data;
  
  	spin_lock_irq(&cm_id_priv->lock);
  	if (cm_id_priv->id.state != IB_CM_REP_SENT &&
  	    cm_id_priv->id.state != IB_CM_MRA_REP_RCVD) {
  		spin_unlock_irq(&cm_id_priv->lock);
  		atomic_long_inc(&work->port->counter_group[CM_RECV_DUPLICATES].
  				counter[CM_RTU_COUNTER]);
  		goto out;
  	}
  	cm_id_priv->id.state = IB_CM_ESTABLISHED;
  
  	ib_cancel_mad(cm_id_priv->av.port->mad_agent, cm_id_priv->msg);
  	ret = atomic_inc_and_test(&cm_id_priv->work_count);
  	if (!ret)
  		list_add_tail(&work->list, &cm_id_priv->work_list);
  	spin_unlock_irq(&cm_id_priv->lock);
  
  	if (ret)
  		cm_process_work(cm_id_priv, work);
  	else
  		cm_deref_id(cm_id_priv);
  	return 0;
  out:
  	cm_deref_id(cm_id_priv);
  	return -EINVAL;
  }
  
  static void cm_format_dreq(struct cm_dreq_msg *dreq_msg,
  			  struct cm_id_private *cm_id_priv,
  			  const void *private_data,
  			  u8 private_data_len)
  {
  	cm_format_mad_hdr(&dreq_msg->hdr, CM_DREQ_ATTR_ID,
  			  cm_form_tid(cm_id_priv, CM_MSG_SEQUENCE_DREQ));
  	dreq_msg->local_comm_id = cm_id_priv->id.local_id;
  	dreq_msg->remote_comm_id = cm_id_priv->id.remote_id;
  	cm_dreq_set_remote_qpn(dreq_msg, cm_id_priv->remote_qpn);
  
  	if (private_data && private_data_len)
  		memcpy(dreq_msg->private_data, private_data, private_data_len);
  }
  
  int ib_send_cm_dreq(struct ib_cm_id *cm_id,
  		    const void *private_data,
  		    u8 private_data_len)
  {
  	struct cm_id_private *cm_id_priv;
  	struct ib_mad_send_buf *msg;
  	unsigned long flags;
  	int ret;
  
  	if (private_data && private_data_len > IB_CM_DREQ_PRIVATE_DATA_SIZE)
  		return -EINVAL;
  
  	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_ESTABLISHED) {
  		ret = -EINVAL;
  		goto out;
  	}
  
  	if (cm_id->lap_state == IB_CM_LAP_SENT ||
  	    cm_id->lap_state == IB_CM_MRA_LAP_RCVD)
  		ib_cancel_mad(cm_id_priv->av.port->mad_agent, cm_id_priv->msg);
  
  	ret = cm_alloc_msg(cm_id_priv, &msg);
  	if (ret) {
  		cm_enter_timewait(cm_id_priv);
  		goto out;
  	}
  
  	cm_format_dreq((struct cm_dreq_msg *) msg->mad, cm_id_priv,
  		       private_data, private_data_len);
  	msg->timeout_ms = cm_id_priv->timeout_ms;
  	msg->context[1] = (void *) (unsigned long) IB_CM_DREQ_SENT;
  
  	ret = ib_post_send_mad(msg, NULL);
  	if (ret) {
  		cm_enter_timewait(cm_id_priv);
  		spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  		cm_free_msg(msg);
  		return ret;
  	}
  
  	cm_id->state = IB_CM_DREQ_SENT;
  	cm_id_priv->msg = msg;
  out:	spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  	return ret;
  }
  EXPORT_SYMBOL(ib_send_cm_dreq);
  
  static void cm_format_drep(struct cm_drep_msg *drep_msg,
  			  struct cm_id_private *cm_id_priv,
  			  const void *private_data,
  			  u8 private_data_len)
  {
  	cm_format_mad_hdr(&drep_msg->hdr, CM_DREP_ATTR_ID, cm_id_priv->tid);
  	drep_msg->local_comm_id = cm_id_priv->id.local_id;
  	drep_msg->remote_comm_id = cm_id_priv->id.remote_id;
  
  	if (private_data && private_data_len)
  		memcpy(drep_msg->private_data, private_data, private_data_len);
  }
  
  int ib_send_cm_drep(struct ib_cm_id *cm_id,
  		    const void *private_data,
  		    u8 private_data_len)
  {
  	struct cm_id_private *cm_id_priv;
  	struct ib_mad_send_buf *msg;
  	unsigned long flags;
  	void *data;
  	int ret;
  
  	if (private_data && private_data_len > IB_CM_DREP_PRIVATE_DATA_SIZE)
  		return -EINVAL;
  
  	data = cm_copy_private_data(private_data, private_data_len);
  	if (IS_ERR(data))
  		return PTR_ERR(data);
  
  	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_DREQ_RCVD) {
  		spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  		kfree(data);
  		return -EINVAL;
  	}
  
  	cm_set_private_data(cm_id_priv, data, private_data_len);
  	cm_enter_timewait(cm_id_priv);
  
  	ret = cm_alloc_msg(cm_id_priv, &msg);
  	if (ret)
  		goto out;
  
  	cm_format_drep((struct cm_drep_msg *) msg->mad, cm_id_priv,
  		       private_data, private_data_len);
  
  	ret = ib_post_send_mad(msg, NULL);
  	if (ret) {
  		spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  		cm_free_msg(msg);
  		return ret;
  	}
  
  out:	spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  	return ret;
  }
  EXPORT_SYMBOL(ib_send_cm_drep);
  
  static int cm_issue_drep(struct cm_port *port,
  			 struct ib_mad_recv_wc *mad_recv_wc)
  {
  	struct ib_mad_send_buf *msg = NULL;
  	struct cm_dreq_msg *dreq_msg;
  	struct cm_drep_msg *drep_msg;
  	int ret;
  
  	ret = cm_alloc_response_msg(port, mad_recv_wc, &msg);
  	if (ret)
  		return ret;
  
  	dreq_msg = (struct cm_dreq_msg *) mad_recv_wc->recv_buf.mad;
  	drep_msg = (struct cm_drep_msg *) msg->mad;
  
  	cm_format_mad_hdr(&drep_msg->hdr, CM_DREP_ATTR_ID, dreq_msg->hdr.tid);
  	drep_msg->remote_comm_id = dreq_msg->local_comm_id;
  	drep_msg->local_comm_id = dreq_msg->remote_comm_id;
  
  	ret = ib_post_send_mad(msg, NULL);
  	if (ret)
  		cm_free_msg(msg);
  
  	return ret;
  }
  
  static int cm_dreq_handler(struct cm_work *work)
  {
  	struct cm_id_private *cm_id_priv;
  	struct cm_dreq_msg *dreq_msg;
  	struct ib_mad_send_buf *msg = NULL;
  	int ret;
  
  	dreq_msg = (struct cm_dreq_msg *)work->mad_recv_wc->recv_buf.mad;
  	cm_id_priv = cm_acquire_id(dreq_msg->remote_comm_id,
  				   dreq_msg->local_comm_id);
  	if (!cm_id_priv) {
  		atomic_long_inc(&work->port->counter_group[CM_RECV_DUPLICATES].
  				counter[CM_DREQ_COUNTER]);
  		cm_issue_drep(work->port, work->mad_recv_wc);
  		return -EINVAL;
  	}
  
  	work->cm_event.private_data = &dreq_msg->private_data;
  
  	spin_lock_irq(&cm_id_priv->lock);
  	if (cm_id_priv->local_qpn != cm_dreq_get_remote_qpn(dreq_msg))
  		goto unlock;
  
  	switch (cm_id_priv->id.state) {
  	case IB_CM_REP_SENT:
  	case IB_CM_DREQ_SENT:
  		ib_cancel_mad(cm_id_priv->av.port->mad_agent, cm_id_priv->msg);
  		break;
  	case IB_CM_ESTABLISHED:
  		if (cm_id_priv->id.lap_state == IB_CM_LAP_SENT ||
  		    cm_id_priv->id.lap_state == IB_CM_MRA_LAP_RCVD)
  			ib_cancel_mad(cm_id_priv->av.port->mad_agent, cm_id_priv->msg);
  		break;
  	case IB_CM_MRA_REP_RCVD:
  		break;
  	case IB_CM_TIMEWAIT:
  		atomic_long_inc(&work->port->counter_group[CM_RECV_DUPLICATES].
  				counter[CM_DREQ_COUNTER]);
  		if (cm_alloc_response_msg(work->port, work->mad_recv_wc, &msg))
  			goto unlock;
  
  		cm_format_drep((struct cm_drep_msg *) msg->mad, cm_id_priv,
  			       cm_id_priv->private_data,
  			       cm_id_priv->private_data_len);
  		spin_unlock_irq(&cm_id_priv->lock);
  
  		if (ib_post_send_mad(msg, NULL))
  			cm_free_msg(msg);
  		goto deref;
  	case IB_CM_DREQ_RCVD:
  		atomic_long_inc(&work->port->counter_group[CM_RECV_DUPLICATES].
  				counter[CM_DREQ_COUNTER]);
  		goto unlock;
  	default:
  		goto unlock;
  	}
  	cm_id_priv->id.state = IB_CM_DREQ_RCVD;
  	cm_id_priv->tid = dreq_msg->hdr.tid;
  	ret = atomic_inc_and_test(&cm_id_priv->work_count);
  	if (!ret)
  		list_add_tail(&work->list, &cm_id_priv->work_list);
  	spin_unlock_irq(&cm_id_priv->lock);
  
  	if (ret)
  		cm_process_work(cm_id_priv, work);
  	else
  		cm_deref_id(cm_id_priv);
  	return 0;
  
  unlock:	spin_unlock_irq(&cm_id_priv->lock);
  deref:	cm_deref_id(cm_id_priv);
  	return -EINVAL;
  }
  
  static int cm_drep_handler(struct cm_work *work)
  {
  	struct cm_id_private *cm_id_priv;
  	struct cm_drep_msg *drep_msg;
  	int ret;
  
  	drep_msg = (struct cm_drep_msg *)work->mad_recv_wc->recv_buf.mad;
  	cm_id_priv = cm_acquire_id(drep_msg->remote_comm_id,
  				   drep_msg->local_comm_id);
  	if (!cm_id_priv)
  		return -EINVAL;
  
  	work->cm_event.private_data = &drep_msg->private_data;
  
  	spin_lock_irq(&cm_id_priv->lock);
  	if (cm_id_priv->id.state != IB_CM_DREQ_SENT &&
  	    cm_id_priv->id.state != IB_CM_DREQ_RCVD) {
  		spin_unlock_irq(&cm_id_priv->lock);
  		goto out;
  	}
  	cm_enter_timewait(cm_id_priv);
  
  	ib_cancel_mad(cm_id_priv->av.port->mad_agent, cm_id_priv->msg);
  	ret = atomic_inc_and_test(&cm_id_priv->work_count);
  	if (!ret)
  		list_add_tail(&work->list, &cm_id_priv->work_list);
  	spin_unlock_irq(&cm_id_priv->lock);
  
  	if (ret)
  		cm_process_work(cm_id_priv, work);
  	else
  		cm_deref_id(cm_id_priv);
  	return 0;
  out:
  	cm_deref_id(cm_id_priv);
  	return -EINVAL;
  }
  
  int ib_send_cm_rej(struct ib_cm_id *cm_id,
  		   enum ib_cm_rej_reason reason,
  		   void *ari,
  		   u8 ari_length,
  		   const void *private_data,
  		   u8 private_data_len)
  {
  	struct cm_id_private *cm_id_priv;
  	struct ib_mad_send_buf *msg;
  	unsigned long flags;
  	int ret;
  
  	if ((private_data && private_data_len > IB_CM_REJ_PRIVATE_DATA_SIZE) ||
  	    (ari && ari_length > IB_CM_REJ_ARI_LENGTH))
  		return -EINVAL;
  
  	cm_id_priv = container_of(cm_id, struct cm_id_private, id);
  
  	spin_lock_irqsave(&cm_id_priv->lock, flags);
  	switch (cm_id->state) {
  	case IB_CM_REQ_SENT:
  	case IB_CM_MRA_REQ_RCVD:
  	case IB_CM_REQ_RCVD:
  	case IB_CM_MRA_REQ_SENT:
  	case IB_CM_REP_RCVD:
  	case IB_CM_MRA_REP_SENT:
  		ret = cm_alloc_msg(cm_id_priv, &msg);
  		if (!ret)
  			cm_format_rej((struct cm_rej_msg *) msg->mad,
  				      cm_id_priv, reason, ari, ari_length,
  				      private_data, private_data_len);
  
  		cm_reset_to_idle(cm_id_priv);
  		break;
  	case IB_CM_REP_SENT:
  	case IB_CM_MRA_REP_RCVD:
  		ret = cm_alloc_msg(cm_id_priv, &msg);
  		if (!ret)
  			cm_format_rej((struct cm_rej_msg *) msg->mad,
  				      cm_id_priv, reason, ari, ari_length,
  				      private_data, private_data_len);
  
  		cm_enter_timewait(cm_id_priv);
  		break;
  	default:
  		ret = -EINVAL;
  		goto out;
  	}
  
  	if (ret)
  		goto out;
  
  	ret = ib_post_send_mad(msg, NULL);
  	if (ret)
  		cm_free_msg(msg);
  
  out:	spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  	return ret;
  }
  EXPORT_SYMBOL(ib_send_cm_rej);
  
  static void cm_format_rej_event(struct cm_work *work)
  {
  	struct cm_rej_msg *rej_msg;
  	struct ib_cm_rej_event_param *param;
  
  	rej_msg = (struct cm_rej_msg *)work->mad_recv_wc->recv_buf.mad;
  	param = &work->cm_event.param.rej_rcvd;
  	param->ari = rej_msg->ari;
  	param->ari_length = cm_rej_get_reject_info_len(rej_msg);
  	param->reason = __be16_to_cpu(rej_msg->reason);
  	work->cm_event.private_data = &rej_msg->private_data;
  }
  
  static struct cm_id_private * cm_acquire_rejected_id(struct cm_rej_msg *rej_msg)
  {
  	struct cm_timewait_info *timewait_info;
  	struct cm_id_private *cm_id_priv;
  	__be32 remote_id;
  
  	remote_id = rej_msg->local_comm_id;
  
  	if (__be16_to_cpu(rej_msg->reason) == IB_CM_REJ_TIMEOUT) {
  		spin_lock_irq(&cm.lock);
  		timewait_info = cm_find_remote_id( *((__be64 *) rej_msg->ari),
  						  remote_id);
  		if (!timewait_info) {
  			spin_unlock_irq(&cm.lock);
  			return NULL;
  		}
  		cm_id_priv = idr_find(&cm.local_id_table, (__force int)
  				      (timewait_info->work.local_id ^
  				       cm.random_id_operand));
  		if (cm_id_priv) {
  			if (cm_id_priv->id.remote_id == remote_id)
  				atomic_inc(&cm_id_priv->refcount);
  			else
  				cm_id_priv = NULL;
  		}
  		spin_unlock_irq(&cm.lock);
  	} else if (cm_rej_get_msg_rejected(rej_msg) == CM_MSG_RESPONSE_REQ)
  		cm_id_priv = cm_acquire_id(rej_msg->remote_comm_id, 0);
  	else
  		cm_id_priv = cm_acquire_id(rej_msg->remote_comm_id, remote_id);
  
  	return cm_id_priv;
  }
  
  static int cm_rej_handler(struct cm_work *work)
  {
  	struct cm_id_private *cm_id_priv;
  	struct cm_rej_msg *rej_msg;
  	int ret;
  
  	rej_msg = (struct cm_rej_msg *)work->mad_recv_wc->recv_buf.mad;
  	cm_id_priv = cm_acquire_rejected_id(rej_msg);
  	if (!cm_id_priv)
  		return -EINVAL;
  
  	cm_format_rej_event(work);
  
  	spin_lock_irq(&cm_id_priv->lock);
  	switch (cm_id_priv->id.state) {
  	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, cm_id_priv->msg);
  		/* fall through */
  	case IB_CM_REQ_RCVD:
  	case IB_CM_MRA_REQ_SENT:
  		if (__be16_to_cpu(rej_msg->reason) == IB_CM_REJ_STALE_CONN)
  			cm_enter_timewait(cm_id_priv);
  		else
  			cm_reset_to_idle(cm_id_priv);
  		break;
  	case IB_CM_DREQ_SENT:
  		ib_cancel_mad(cm_id_priv->av.port->mad_agent, cm_id_priv->msg);
  		/* fall through */
  	case IB_CM_REP_RCVD:
  	case IB_CM_MRA_REP_SENT:
  		cm_enter_timewait(cm_id_priv);
  		break;
  	case IB_CM_ESTABLISHED:
  		if (cm_id_priv->id.lap_state == IB_CM_LAP_UNINIT ||
  		    cm_id_priv->id.lap_state == IB_CM_LAP_SENT) {
  			if (cm_id_priv->id.lap_state == IB_CM_LAP_SENT)
  				ib_cancel_mad(cm_id_priv->av.port->mad_agent,
  					      cm_id_priv->msg);
  			cm_enter_timewait(cm_id_priv);
  			break;
  		}
  		/* fall through */
  	default:
  		spin_unlock_irq(&cm_id_priv->lock);
  		ret = -EINVAL;
  		goto out;
  	}
  
  	ret = atomic_inc_and_test(&cm_id_priv->work_count);
  	if (!ret)
  		list_add_tail(&work->list, &cm_id_priv->work_list);
  	spin_unlock_irq(&cm_id_priv->lock);
  
  	if (ret)
  		cm_process_work(cm_id_priv, work);
  	else
  		cm_deref_id(cm_id_priv);
  	return 0;
  out:
  	cm_deref_id(cm_id_priv);
  	return -EINVAL;
  }
  
  int ib_send_cm_mra(struct ib_cm_id *cm_id,
  		   u8 service_timeout,
  		   const void *private_data,
  		   u8 private_data_len)
  {
  	struct cm_id_private *cm_id_priv;
  	struct ib_mad_send_buf *msg;
  	enum ib_cm_state cm_state;
  	enum ib_cm_lap_state lap_state;
  	enum cm_msg_response msg_response;
  	void *data;
  	unsigned long flags;
  	int ret;
  
  	if (private_data && private_data_len > IB_CM_MRA_PRIVATE_DATA_SIZE)
  		return -EINVAL;
  
  	data = cm_copy_private_data(private_data, private_data_len);
  	if (IS_ERR(data))
  		return PTR_ERR(data);
  
  	cm_id_priv = container_of(cm_id, struct cm_id_private, id);
  
  	spin_lock_irqsave(&cm_id_priv->lock, flags);
  	switch(cm_id_priv->id.state) {
  	case IB_CM_REQ_RCVD:
  		cm_state = IB_CM_MRA_REQ_SENT;
  		lap_state = cm_id->lap_state;
  		msg_response = CM_MSG_RESPONSE_REQ;
  		break;
  	case IB_CM_REP_RCVD:
  		cm_state = IB_CM_MRA_REP_SENT;
  		lap_state = cm_id->lap_state;
  		msg_response = CM_MSG_RESPONSE_REP;
  		break;
  	case IB_CM_ESTABLISHED:
  		if (cm_id->lap_state == IB_CM_LAP_RCVD) {
  			cm_state = cm_id->state;
  			lap_state = IB_CM_MRA_LAP_SENT;
  			msg_response = CM_MSG_RESPONSE_OTHER;
  			break;
  		}
  	default:
  		ret = -EINVAL;
  		goto error1;
  	}
  
  	if (!(service_timeout & IB_CM_MRA_FLAG_DELAY)) {
  		ret = cm_alloc_msg(cm_id_priv, &msg);
  		if (ret)
  			goto error1;
  
  		cm_format_mra((struct cm_mra_msg *) msg->mad, cm_id_priv,
  			      msg_response, service_timeout,
  			      private_data, private_data_len);
  		ret = ib_post_send_mad(msg, NULL);
  		if (ret)
  			goto error2;
  	}
  
  	cm_id->state = cm_state;
  	cm_id->lap_state = lap_state;
  	cm_id_priv->service_timeout = service_timeout;
  	cm_set_private_data(cm_id_priv, data, private_data_len);
  	spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  	return 0;
  
  error1:	spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  	kfree(data);
  	return ret;
  
  error2:	spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  	kfree(data);
  	cm_free_msg(msg);
  	return ret;
  }
  EXPORT_SYMBOL(ib_send_cm_mra);
  
  static struct cm_id_private * cm_acquire_mraed_id(struct cm_mra_msg *mra_msg)
  {
  	switch (cm_mra_get_msg_mraed(mra_msg)) {
  	case CM_MSG_RESPONSE_REQ:
  		return cm_acquire_id(mra_msg->remote_comm_id, 0);
  	case CM_MSG_RESPONSE_REP:
  	case CM_MSG_RESPONSE_OTHER:
  		return cm_acquire_id(mra_msg->remote_comm_id,
  				     mra_msg->local_comm_id);
  	default:
  		return NULL;
  	}
  }
  
  static int cm_mra_handler(struct cm_work *work)
  {
  	struct cm_id_private *cm_id_priv;
  	struct cm_mra_msg *mra_msg;
  	int timeout, ret;
  
  	mra_msg = (struct cm_mra_msg *)work->mad_recv_wc->recv_buf.mad;
  	cm_id_priv = cm_acquire_mraed_id(mra_msg);
  	if (!cm_id_priv)
  		return -EINVAL;
  
  	work->cm_event.private_data = &mra_msg->private_data;
  	work->cm_event.param.mra_rcvd.service_timeout =
  					cm_mra_get_service_timeout(mra_msg);
  	timeout = cm_convert_to_ms(cm_mra_get_service_timeout(mra_msg)) +
  		  cm_convert_to_ms(cm_id_priv->av.timeout);
  
  	spin_lock_irq(&cm_id_priv->lock);
  	switch (cm_id_priv->id.state) {
  	case IB_CM_REQ_SENT:
  		if (cm_mra_get_msg_mraed(mra_msg) != CM_MSG_RESPONSE_REQ ||
  		    ib_modify_mad(cm_id_priv->av.port->mad_agent,
  				  cm_id_priv->msg, timeout))
  			goto out;
  		cm_id_priv->id.state = IB_CM_MRA_REQ_RCVD;
  		break;
  	case IB_CM_REP_SENT:
  		if (cm_mra_get_msg_mraed(mra_msg) != CM_MSG_RESPONSE_REP ||
  		    ib_modify_mad(cm_id_priv->av.port->mad_agent,
  				  cm_id_priv->msg, timeout))
  			goto out;
  		cm_id_priv->id.state = IB_CM_MRA_REP_RCVD;
  		break;
  	case IB_CM_ESTABLISHED:
  		if (cm_mra_get_msg_mraed(mra_msg) != CM_MSG_RESPONSE_OTHER ||
  		    cm_id_priv->id.lap_state != IB_CM_LAP_SENT ||
  		    ib_modify_mad(cm_id_priv->av.port->mad_agent,
  				  cm_id_priv->msg, timeout)) {
  			if (cm_id_priv->id.lap_state == IB_CM_MRA_LAP_RCVD)
  				atomic_long_inc(&work->port->
  						counter_group[CM_RECV_DUPLICATES].
  						counter[CM_MRA_COUNTER]);
  			goto out;
  		}
  		cm_id_priv->id.lap_state = IB_CM_MRA_LAP_RCVD;
  		break;
  	case IB_CM_MRA_REQ_RCVD:
  	case IB_CM_MRA_REP_RCVD:
  		atomic_long_inc(&work->port->counter_group[CM_RECV_DUPLICATES].
  				counter[CM_MRA_COUNTER]);
  		/* fall through */
  	default:
  		goto out;
  	}
  
  	cm_id_priv->msg->context[1] = (void *) (unsigned long)
  				      cm_id_priv->id.state;
  	ret = atomic_inc_and_test(&cm_id_priv->work_count);
  	if (!ret)
  		list_add_tail(&work->list, &cm_id_priv->work_list);
  	spin_unlock_irq(&cm_id_priv->lock);
  
  	if (ret)
  		cm_process_work(cm_id_priv, work);
  	else
  		cm_deref_id(cm_id_priv);
  	return 0;
  out:
  	spin_unlock_irq(&cm_id_priv->lock);
  	cm_deref_id(cm_id_priv);
  	return -EINVAL;
  }
  
  static void cm_format_lap(struct cm_lap_msg *lap_msg,
  			  struct cm_id_private *cm_id_priv,
  			  struct ib_sa_path_rec *alternate_path,
  			  const void *private_data,
  			  u8 private_data_len)
  {
  	cm_format_mad_hdr(&lap_msg->hdr, CM_LAP_ATTR_ID,
  			  cm_form_tid(cm_id_priv, CM_MSG_SEQUENCE_LAP));
  	lap_msg->local_comm_id = cm_id_priv->id.local_id;
  	lap_msg->remote_comm_id = cm_id_priv->id.remote_id;
  	cm_lap_set_remote_qpn(lap_msg, cm_id_priv->remote_qpn);
  	/* todo: need remote CM response timeout */
  	cm_lap_set_remote_resp_timeout(lap_msg, 0x1F);
  	lap_msg->alt_local_lid = alternate_path->slid;
  	lap_msg->alt_remote_lid = alternate_path->dlid;
  	lap_msg->alt_local_gid = alternate_path->sgid;
  	lap_msg->alt_remote_gid = alternate_path->dgid;
  	cm_lap_set_flow_label(lap_msg, alternate_path->flow_label);
  	cm_lap_set_traffic_class(lap_msg, alternate_path->traffic_class);
  	lap_msg->alt_hop_limit = alternate_path->hop_limit;
  	cm_lap_set_packet_rate(lap_msg, alternate_path->rate);
  	cm_lap_set_sl(lap_msg, alternate_path->sl);
  	cm_lap_set_subnet_local(lap_msg, 1); /* local only... */
  	cm_lap_set_local_ack_timeout(lap_msg,
  		cm_ack_timeout(cm_id_priv->av.port->cm_dev->ack_delay,
  			       alternate_path->packet_life_time));
  
  	if (private_data && private_data_len)
  		memcpy(lap_msg->private_data, private_data, private_data_len);
  }
  
  int ib_send_cm_lap(struct ib_cm_id *cm_id,
  		   struct ib_sa_path_rec *alternate_path,
  		   const void *private_data,
  		   u8 private_data_len)
  {
  	struct cm_id_private *cm_id_priv;
  	struct ib_mad_send_buf *msg;
  	unsigned long flags;
  	int ret;
  
  	if (private_data && private_data_len > IB_CM_LAP_PRIVATE_DATA_SIZE)
  		return -EINVAL;
  
  	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_ESTABLISHED ||
  	    (cm_id->lap_state != IB_CM_LAP_UNINIT &&
  	     cm_id->lap_state != IB_CM_LAP_IDLE)) {
  		ret = -EINVAL;
  		goto out;
  	}
  
  	ret = cm_init_av_by_path(alternate_path, &cm_id_priv->alt_av);
  	if (ret)
  		goto out;
  	cm_id_priv->alt_av.timeout =
  			cm_ack_timeout(cm_id_priv->target_ack_delay,
  				       cm_id_priv->alt_av.timeout - 1);
  
  	ret = cm_alloc_msg(cm_id_priv, &msg);
  	if (ret)
  		goto out;
  
  	cm_format_lap((struct cm_lap_msg *) msg->mad, cm_id_priv,
  		      alternate_path, private_data, private_data_len);
  	msg->timeout_ms = cm_id_priv->timeout_ms;
  	msg->context[1] = (void *) (unsigned long) IB_CM_ESTABLISHED;
  
  	ret = ib_post_send_mad(msg, NULL);
  	if (ret) {
  		spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  		cm_free_msg(msg);
  		return ret;
  	}
  
  	cm_id->lap_state = IB_CM_LAP_SENT;
  	cm_id_priv->msg = msg;
  
  out:	spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  	return ret;
  }
  EXPORT_SYMBOL(ib_send_cm_lap);
  
  static void cm_format_path_from_lap(struct cm_id_private *cm_id_priv,
  				    struct ib_sa_path_rec *path,
  				    struct cm_lap_msg *lap_msg)
  {
  	memset(path, 0, sizeof *path);
  	path->dgid = lap_msg->alt_local_gid;
  	path->sgid = lap_msg->alt_remote_gid;
  	path->dlid = lap_msg->alt_local_lid;
  	path->slid = lap_msg->alt_remote_lid;
  	path->flow_label = cm_lap_get_flow_label(lap_msg);
  	path->hop_limit = lap_msg->alt_hop_limit;
  	path->traffic_class = cm_lap_get_traffic_class(lap_msg);
  	path->reversible = 1;
  	path->pkey = cm_id_priv->pkey;
  	path->sl = cm_lap_get_sl(lap_msg);
  	path->mtu_selector = IB_SA_EQ;
  	path->mtu = cm_id_priv->path_mtu;
  	path->rate_selector = IB_SA_EQ;
  	path->rate = cm_lap_get_packet_rate(lap_msg);
  	path->packet_life_time_selector = IB_SA_EQ;
  	path->packet_life_time = cm_lap_get_local_ack_timeout(lap_msg);
  	path->packet_life_time -= (path->packet_life_time > 0);
  }
  
  static int cm_lap_handler(struct cm_work *work)
  {
  	struct cm_id_private *cm_id_priv;
  	struct cm_lap_msg *lap_msg;
  	struct ib_cm_lap_event_param *param;
  	struct ib_mad_send_buf *msg = NULL;
  	int ret;
  
  	/* todo: verify LAP request and send reject APR if invalid. */
  	lap_msg = (struct cm_lap_msg *)work->mad_recv_wc->recv_buf.mad;
  	cm_id_priv = cm_acquire_id(lap_msg->remote_comm_id,
  				   lap_msg->local_comm_id);
  	if (!cm_id_priv)
  		return -EINVAL;
  
  	param = &work->cm_event.param.lap_rcvd;
  	param->alternate_path = &work->path[0];
  	cm_format_path_from_lap(cm_id_priv, param->alternate_path, lap_msg);
  	work->cm_event.private_data = &lap_msg->private_data;
  
  	spin_lock_irq(&cm_id_priv->lock);
  	if (cm_id_priv->id.state != IB_CM_ESTABLISHED)
  		goto unlock;
  
  	switch (cm_id_priv->id.lap_state) {
  	case IB_CM_LAP_UNINIT:
  	case IB_CM_LAP_IDLE:
  		break;
  	case IB_CM_MRA_LAP_SENT:
  		atomic_long_inc(&work->port->counter_group[CM_RECV_DUPLICATES].
  				counter[CM_LAP_COUNTER]);
  		if (cm_alloc_response_msg(work->port, work->mad_recv_wc, &msg))
  			goto unlock;
  
  		cm_format_mra((struct cm_mra_msg *) msg->mad, cm_id_priv,
  			      CM_MSG_RESPONSE_OTHER,
  			      cm_id_priv->service_timeout,
  			      cm_id_priv->private_data,
  			      cm_id_priv->private_data_len);
  		spin_unlock_irq(&cm_id_priv->lock);
  
  		if (ib_post_send_mad(msg, NULL))
  			cm_free_msg(msg);
  		goto deref;
  	case IB_CM_LAP_RCVD:
  		atomic_long_inc(&work->port->counter_group[CM_RECV_DUPLICATES].
  				counter[CM_LAP_COUNTER]);
  		goto unlock;
  	default:
  		goto unlock;
  	}
  
  	cm_id_priv->id.lap_state = IB_CM_LAP_RCVD;
  	cm_id_priv->tid = lap_msg->hdr.tid;
  	cm_init_av_for_response(work->port, work->mad_recv_wc->wc,
  				work->mad_recv_wc->recv_buf.grh,
  				&cm_id_priv->av);
  	cm_init_av_by_path(param->alternate_path, &cm_id_priv->alt_av);
  	ret = atomic_inc_and_test(&cm_id_priv->work_count);
  	if (!ret)
  		list_add_tail(&work->list, &cm_id_priv->work_list);
  	spin_unlock_irq(&cm_id_priv->lock);
  
  	if (ret)
  		cm_process_work(cm_id_priv, work);
  	else
  		cm_deref_id(cm_id_priv);
  	return 0;
  
  unlock:	spin_unlock_irq(&cm_id_priv->lock);
  deref:	cm_deref_id(cm_id_priv);
  	return -EINVAL;
  }
  
  static void cm_format_apr(struct cm_apr_msg *apr_msg,
  			  struct cm_id_private *cm_id_priv,
  			  enum ib_cm_apr_status status,
  			  void *info,
  			  u8 info_length,
  			  const void *private_data,
  			  u8 private_data_len)
  {
  	cm_format_mad_hdr(&apr_msg->hdr, CM_APR_ATTR_ID, cm_id_priv->tid);
  	apr_msg->local_comm_id = cm_id_priv->id.local_id;
  	apr_msg->remote_comm_id = cm_id_priv->id.remote_id;
  	apr_msg->ap_status = (u8) status;
  
  	if (info && info_length) {
  		apr_msg->info_length = info_length;
  		memcpy(apr_msg->info, info, info_length);
  	}
  
  	if (private_data && private_data_len)
  		memcpy(apr_msg->private_data, private_data, private_data_len);
  }
  
  int ib_send_cm_apr(struct ib_cm_id *cm_id,
  		   enum ib_cm_apr_status status,
  		   void *info,
  		   u8 info_length,
  		   const void *private_data,
  		   u8 private_data_len)
  {
  	struct cm_id_private *cm_id_priv;
  	struct ib_mad_send_buf *msg;
  	unsigned long flags;
  	int ret;
  
  	if ((private_data && private_data_len > IB_CM_APR_PRIVATE_DATA_SIZE) ||
  	    (info && info_length > IB_CM_APR_INFO_LENGTH))
  		return -EINVAL;
  
  	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_ESTABLISHED ||
  	    (cm_id->lap_state != IB_CM_LAP_RCVD &&
  	     cm_id->lap_state != IB_CM_MRA_LAP_SENT)) {
  		ret = -EINVAL;
  		goto out;
  	}
  
  	ret = cm_alloc_msg(cm_id_priv, &msg);
  	if (ret)
  		goto out;
  
  	cm_format_apr((struct cm_apr_msg *) msg->mad, cm_id_priv, status,
  		      info, info_length, private_data, private_data_len);
  	ret = ib_post_send_mad(msg, NULL);
  	if (ret) {
  		spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  		cm_free_msg(msg);
  		return ret;
  	}
  
  	cm_id->lap_state = IB_CM_LAP_IDLE;
  out:	spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  	return ret;
  }
  EXPORT_SYMBOL(ib_send_cm_apr);
  
  static int cm_apr_handler(struct cm_work *work)
  {
  	struct cm_id_private *cm_id_priv;
  	struct cm_apr_msg *apr_msg;
  	int ret;
  
  	apr_msg = (struct cm_apr_msg *)work->mad_recv_wc->recv_buf.mad;
  	cm_id_priv = cm_acquire_id(apr_msg->remote_comm_id,
  				   apr_msg->local_comm_id);
  	if (!cm_id_priv)
  		return -EINVAL; /* Unmatched reply. */
  
  	work->cm_event.param.apr_rcvd.ap_status = apr_msg->ap_status;
  	work->cm_event.param.apr_rcvd.apr_info = &apr_msg->info;
  	work->cm_event.param.apr_rcvd.info_len = apr_msg->info_length;
  	work->cm_event.private_data = &apr_msg->private_data;
  
  	spin_lock_irq(&cm_id_priv->lock);
  	if (cm_id_priv->id.state != IB_CM_ESTABLISHED ||
  	    (cm_id_priv->id.lap_state != IB_CM_LAP_SENT &&
  	     cm_id_priv->id.lap_state != IB_CM_MRA_LAP_RCVD)) {
  		spin_unlock_irq(&cm_id_priv->lock);
  		goto out;
  	}
  	cm_id_priv->id.lap_state = IB_CM_LAP_IDLE;
  	ib_cancel_mad(cm_id_priv->av.port->mad_agent, cm_id_priv->msg);
  	cm_id_priv->msg = NULL;
  
  	ret = atomic_inc_and_test(&cm_id_priv->work_count);
  	if (!ret)
  		list_add_tail(&work->list, &cm_id_priv->work_list);
  	spin_unlock_irq(&cm_id_priv->lock);
  
  	if (ret)
  		cm_process_work(cm_id_priv, work);
  	else
  		cm_deref_id(cm_id_priv);
  	return 0;
  out:
  	cm_deref_id(cm_id_priv);
  	return -EINVAL;
  }
  
  static int cm_timewait_handler(struct cm_work *work)
  {
  	struct cm_timewait_info *timewait_info;
  	struct cm_id_private *cm_id_priv;
  	int ret;
  
  	timewait_info = (struct cm_timewait_info *)work;
  	spin_lock_irq(&cm.lock);
  	list_del(&timewait_info->list);
  	spin_unlock_irq(&cm.lock);
  
  	cm_id_priv = cm_acquire_id(timewait_info->work.local_id,
  				   timewait_info->work.remote_id);
  	if (!cm_id_priv)
  		return -EINVAL;
  
  	spin_lock_irq(&cm_id_priv->lock);
  	if (cm_id_priv->id.state != IB_CM_TIMEWAIT ||
  	    cm_id_priv->remote_qpn != timewait_info->remote_qpn) {
  		spin_unlock_irq(&cm_id_priv->lock);
  		goto out;
  	}
  	cm_id_priv->id.state = IB_CM_IDLE;
  	ret = atomic_inc_and_test(&cm_id_priv->work_count);
  	if (!ret)
  		list_add_tail(&work->list, &cm_id_priv->work_list);
  	spin_unlock_irq(&cm_id_priv->lock);
  
  	if (ret)
  		cm_process_work(cm_id_priv, work);
  	else
  		cm_deref_id(cm_id_priv);
  	return 0;
  out:
  	cm_deref_id(cm_id_priv);
  	return -EINVAL;
  }
  
  static void cm_format_sidr_req(struct cm_sidr_req_msg *sidr_req_msg,
  			       struct cm_id_private *cm_id_priv,
  			       struct ib_cm_sidr_req_param *param)
  {
  	cm_format_mad_hdr(&sidr_req_msg->hdr, CM_SIDR_REQ_ATTR_ID,
  			  cm_form_tid(cm_id_priv, CM_MSG_SEQUENCE_SIDR));
  	sidr_req_msg->request_id = cm_id_priv->id.local_id;
  	sidr_req_msg->pkey = param->path->pkey;
  	sidr_req_msg->service_id = param->service_id;
  
  	if (param->private_data && param->private_data_len)
  		memcpy(sidr_req_msg->private_data, param->private_data,
  		       param->private_data_len);
  }
  
  int ib_send_cm_sidr_req(struct ib_cm_id *cm_id,
  			struct ib_cm_sidr_req_param *param)
  {
  	struct cm_id_private *cm_id_priv;
  	struct ib_mad_send_buf *msg;
  	unsigned long flags;
  	int ret;
  
  	if (!param->path || (param->private_data &&
  	     param->private_data_len > IB_CM_SIDR_REQ_PRIVATE_DATA_SIZE))
  		return -EINVAL;
  
  	cm_id_priv = container_of(cm_id, struct cm_id_private, id);
  	ret = cm_init_av_by_path(param->path, &cm_id_priv->av);
  	if (ret)
  		goto out;
  
  	cm_id->service_id = param->service_id;
  	cm_id->service_mask = ~cpu_to_be64(0);
  	cm_id_priv->timeout_ms = param->timeout_ms;
  	cm_id_priv->max_cm_retries = param->max_cm_retries;
  	ret = cm_alloc_msg(cm_id_priv, &msg);
  	if (ret)
  		goto out;
  
  	cm_format_sidr_req((struct cm_sidr_req_msg *) msg->mad, cm_id_priv,
  			   param);
  	msg->timeout_ms = cm_id_priv->timeout_ms;
  	msg->context[1] = (void *) (unsigned long) IB_CM_SIDR_REQ_SENT;
  
  	spin_lock_irqsave(&cm_id_priv->lock, flags);
  	if (cm_id->state == IB_CM_IDLE)
  		ret = ib_post_send_mad(msg, NULL);
  	else
  		ret = -EINVAL;
  
  	if (ret) {
  		spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  		cm_free_msg(msg);
  		goto out;
  	}
  	cm_id->state = IB_CM_SIDR_REQ_SENT;
  	cm_id_priv->msg = msg;
  	spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  out:
  	return ret;
  }
  EXPORT_SYMBOL(ib_send_cm_sidr_req);
  
  static void cm_format_sidr_req_event(struct cm_work *work,
  				     struct ib_cm_id *listen_id)
  {
  	struct cm_sidr_req_msg *sidr_req_msg;
  	struct ib_cm_sidr_req_event_param *param;
  
  	sidr_req_msg = (struct cm_sidr_req_msg *)
  				work->mad_recv_wc->recv_buf.mad;
  	param = &work->cm_event.param.sidr_req_rcvd;
  	param->pkey = __be16_to_cpu(sidr_req_msg->pkey);
  	param->listen_id = listen_id;
  	param->port = work->port->port_num;
  	work->cm_event.private_data = &sidr_req_msg->private_data;
  }
  
  static int cm_sidr_req_handler(struct cm_work *work)
  {
  	struct ib_cm_id *cm_id;
  	struct cm_id_private *cm_id_priv, *cur_cm_id_priv;
  	struct cm_sidr_req_msg *sidr_req_msg;
  	struct ib_wc *wc;
  
  	cm_id = ib_create_cm_id(work->port->cm_dev->ib_device, NULL, NULL);
  	if (IS_ERR(cm_id))
  		return PTR_ERR(cm_id);
  	cm_id_priv = container_of(cm_id, struct cm_id_private, id);
  
  	/* Record SGID/SLID and request ID for lookup. */
  	sidr_req_msg = (struct cm_sidr_req_msg *)
  				work->mad_recv_wc->recv_buf.mad;
  	wc = work->mad_recv_wc->wc;
  	cm_id_priv->av.dgid.global.subnet_prefix = cpu_to_be64(wc->slid);
  	cm_id_priv->av.dgid.global.interface_id = 0;
  	cm_init_av_for_response(work->port, work->mad_recv_wc->wc,
  				work->mad_recv_wc->recv_buf.grh,
  				&cm_id_priv->av);
  	cm_id_priv->id.remote_id = sidr_req_msg->request_id;
  	cm_id_priv->tid = sidr_req_msg->hdr.tid;
  	atomic_inc(&cm_id_priv->work_count);
  
  	spin_lock_irq(&cm.lock);
  	cur_cm_id_priv = cm_insert_remote_sidr(cm_id_priv);
  	if (cur_cm_id_priv) {
  		spin_unlock_irq(&cm.lock);
  		atomic_long_inc(&work->port->counter_group[CM_RECV_DUPLICATES].
  				counter[CM_SIDR_REQ_COUNTER]);
  		goto out; /* Duplicate message. */
  	}
  	cm_id_priv->id.state = IB_CM_SIDR_REQ_RCVD;
  	cur_cm_id_priv = cm_find_listen(cm_id->device,
  					sidr_req_msg->service_id,
  					sidr_req_msg->private_data);
  	if (!cur_cm_id_priv) {
  		spin_unlock_irq(&cm.lock);
  		cm_reject_sidr_req(cm_id_priv, IB_SIDR_UNSUPPORTED);
  		goto out; /* No match. */
  	}
  	atomic_inc(&cur_cm_id_priv->refcount);
  	atomic_inc(&cm_id_priv->refcount);
  	spin_unlock_irq(&cm.lock);
  
  	cm_id_priv->id.cm_handler = cur_cm_id_priv->id.cm_handler;
  	cm_id_priv->id.context = cur_cm_id_priv->id.context;
  	cm_id_priv->id.service_id = sidr_req_msg->service_id;
  	cm_id_priv->id.service_mask = ~cpu_to_be64(0);
  
  	cm_format_sidr_req_event(work, &cur_cm_id_priv->id);
  	cm_process_work(cm_id_priv, work);
  	cm_deref_id(cur_cm_id_priv);
  	return 0;
  out:
  	ib_destroy_cm_id(&cm_id_priv->id);
  	return -EINVAL;
  }
  
  static void cm_format_sidr_rep(struct cm_sidr_rep_msg *sidr_rep_msg,
  			       struct cm_id_private *cm_id_priv,
  			       struct ib_cm_sidr_rep_param *param)
  {
  	cm_format_mad_hdr(&sidr_rep_msg->hdr, CM_SIDR_REP_ATTR_ID,
  			  cm_id_priv->tid);
  	sidr_rep_msg->request_id = cm_id_priv->id.remote_id;
  	sidr_rep_msg->status = param->status;
  	cm_sidr_rep_set_qpn(sidr_rep_msg, cpu_to_be32(param->qp_num));
  	sidr_rep_msg->service_id = cm_id_priv->id.service_id;
  	sidr_rep_msg->qkey = cpu_to_be32(param->qkey);
  
  	if (param->info && param->info_length)
  		memcpy(sidr_rep_msg->info, param->info, param->info_length);
  
  	if (param->private_data && param->private_data_len)
  		memcpy(sidr_rep_msg->private_data, param->private_data,
  		       param->private_data_len);
  }
  
  int ib_send_cm_sidr_rep(struct ib_cm_id *cm_id,
  			struct ib_cm_sidr_rep_param *param)
  {
  	struct cm_id_private *cm_id_priv;
  	struct ib_mad_send_buf *msg;
  	unsigned long flags;
  	int ret;
  
  	if ((param->info && param->info_length > IB_CM_SIDR_REP_INFO_LENGTH) ||
  	    (param->private_data &&
  	     param->private_data_len > IB_CM_SIDR_REP_PRIVATE_DATA_SIZE))
  		return -EINVAL;
  
  	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_SIDR_REQ_RCVD) {
  		ret = -EINVAL;
  		goto error;
  	}
  
  	ret = cm_alloc_msg(cm_id_priv, &msg);
  	if (ret)
  		goto error;
  
  	cm_format_sidr_rep((struct cm_sidr_rep_msg *) msg->mad, cm_id_priv,
  			   param);
  	ret = ib_post_send_mad(msg, NULL);
  	if (ret) {
  		spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  		cm_free_msg(msg);
  		return ret;
  	}
  	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->sidr_id_node, &cm.remote_sidr_table);
  	spin_unlock_irqrestore(&cm.lock, flags);
  	return 0;
  
  error:	spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  	return ret;
  }
  EXPORT_SYMBOL(ib_send_cm_sidr_rep);
  
  static void cm_format_sidr_rep_event(struct cm_work *work)
  {
  	struct cm_sidr_rep_msg *sidr_rep_msg;
  	struct ib_cm_sidr_rep_event_param *param;
  
  	sidr_rep_msg = (struct cm_sidr_rep_msg *)
  				work->mad_recv_wc->recv_buf.mad;
  	param = &work->cm_event.param.sidr_rep_rcvd;
  	param->status = sidr_rep_msg->status;
  	param->qkey = be32_to_cpu(sidr_rep_msg->qkey);
  	param->qpn = be32_to_cpu(cm_sidr_rep_get_qpn(sidr_rep_msg));
  	param->info = &sidr_rep_msg->info;
  	param->info_len = sidr_rep_msg->info_length;
  	work->cm_event.private_data = &sidr_rep_msg->private_data;
  }
  
  static int cm_sidr_rep_handler(struct cm_work *work)
  {
  	struct cm_sidr_rep_msg *sidr_rep_msg;
  	struct cm_id_private *cm_id_priv;
  
  	sidr_rep_msg = (struct cm_sidr_rep_msg *)
  				work->mad_recv_wc->recv_buf.mad;
  	cm_id_priv = cm_acquire_id(sidr_rep_msg->request_id, 0);
  	if (!cm_id_priv)
  		return -EINVAL; /* Unmatched reply. */
  
  	spin_lock_irq(&cm_id_priv->lock);
  	if (cm_id_priv->id.state != IB_CM_SIDR_REQ_SENT) {
  		spin_unlock_irq(&cm_id_priv->lock);
  		goto out;
  	}
  	cm_id_priv->id.state = IB_CM_IDLE;
  	ib_cancel_mad(cm_id_priv->av.port->mad_agent, cm_id_priv->msg);
  	spin_unlock_irq(&cm_id_priv->lock);
  
  	cm_format_sidr_rep_event(work);
  	cm_process_work(cm_id_priv, work);
  	return 0;
  out:
  	cm_deref_id(cm_id_priv);
  	return -EINVAL;
  }
  
  static void cm_process_send_error(struct ib_mad_send_buf *msg,
  				  enum ib_wc_status wc_status)
  {
  	struct cm_id_private *cm_id_priv;
  	struct ib_cm_event cm_event;
  	enum ib_cm_state state;
  	int ret;
  
  	memset(&cm_event, 0, sizeof cm_event);
  	cm_id_priv = msg->context[0];
  
  	/* Discard old sends or ones without a response. */
  	spin_lock_irq(&cm_id_priv->lock);
  	state = (enum ib_cm_state) (unsigned long) msg->context[1];
  	if (msg != cm_id_priv->msg || state != cm_id_priv->id.state)
  		goto discard;
  
  	switch (state) {
  	case IB_CM_REQ_SENT:
  	case IB_CM_MRA_REQ_RCVD:
  		cm_reset_to_idle(cm_id_priv);
  		cm_event.event = IB_CM_REQ_ERROR;
  		break;
  	case IB_CM_REP_SENT:
  	case IB_CM_MRA_REP_RCVD:
  		cm_reset_to_idle(cm_id_priv);
  		cm_event.event = IB_CM_REP_ERROR;
  		break;
  	case IB_CM_DREQ_SENT:
  		cm_enter_timewait(cm_id_priv);
  		cm_event.event = IB_CM_DREQ_ERROR;
  		break;
  	case IB_CM_SIDR_REQ_SENT:
  		cm_id_priv->id.state = IB_CM_IDLE;
  		cm_event.event = IB_CM_SIDR_REQ_ERROR;
  		break;
  	default:
  		goto discard;
  	}
  	spin_unlock_irq(&cm_id_priv->lock);
  	cm_event.param.send_status = wc_status;
  
  	/* No other events can occur on the cm_id at this point. */
  	ret = cm_id_priv->id.cm_handler(&cm_id_priv->id, &cm_event);
  	cm_free_msg(msg);
  	if (ret)
  		ib_destroy_cm_id(&cm_id_priv->id);
  	return;
  discard:
  	spin_unlock_irq(&cm_id_priv->lock);
  	cm_free_msg(msg);
  }
  
  static void cm_send_handler(struct ib_mad_agent *mad_agent,
  			    struct ib_mad_send_wc *mad_send_wc)
  {
  	struct ib_mad_send_buf *msg = mad_send_wc->send_buf;
  	struct cm_port *port;
  	u16 attr_index;
  
  	port = mad_agent->context;
  	attr_index = be16_to_cpu(((struct ib_mad_hdr *)
  				  msg->mad)->attr_id) - CM_ATTR_ID_OFFSET;
  
  	/*
  	 * If the send was in response to a received message (context[0] is not
  	 * set to a cm_id), and is not a REJ, then it is a send that was
  	 * manually retried.
  	 */
  	if (!msg->context[0] && (attr_index != CM_REJ_COUNTER))
  		msg->retries = 1;
  
  	atomic_long_add(1 + msg->retries,
  			&port->counter_group[CM_XMIT].counter[attr_index]);
  	if (msg->retries)
  		atomic_long_add(msg->retries,
  				&port->counter_group[CM_XMIT_RETRIES].
  				counter[attr_index]);
  
  	switch (mad_send_wc->status) {
  	case IB_WC_SUCCESS:
  	case IB_WC_WR_FLUSH_ERR:
  		cm_free_msg(msg);
  		break;
  	default:
  		if (msg->context[0] && msg->context[1])
  			cm_process_send_error(msg, mad_send_wc->status);
  		else
  			cm_free_msg(msg);
  		break;
  	}
  }
  
  static void cm_work_handler(struct work_struct *_work)
  {
  	struct cm_work *work = container_of(_work, struct cm_work, work.work);
  	int ret;
  
  	switch (work->cm_event.event) {
  	case IB_CM_REQ_RECEIVED:
  		ret = cm_req_handler(work);
  		break;
  	case IB_CM_MRA_RECEIVED:
  		ret = cm_mra_handler(work);
  		break;
  	case IB_CM_REJ_RECEIVED:
  		ret = cm_rej_handler(work);
  		break;
  	case IB_CM_REP_RECEIVED:
  		ret = cm_rep_handler(work);
  		break;
  	case IB_CM_RTU_RECEIVED:
  		ret = cm_rtu_handler(work);
  		break;
  	case IB_CM_USER_ESTABLISHED:
  		ret = cm_establish_handler(work);
  		break;
  	case IB_CM_DREQ_RECEIVED:
  		ret = cm_dreq_handler(work);
  		break;
  	case IB_CM_DREP_RECEIVED:
  		ret = cm_drep_handler(work);
  		break;
  	case IB_CM_SIDR_REQ_RECEIVED:
  		ret = cm_sidr_req_handler(work);
  		break;
  	case IB_CM_SIDR_REP_RECEIVED:
  		ret = cm_sidr_rep_handler(work);
  		break;
  	case IB_CM_LAP_RECEIVED:
  		ret = cm_lap_handler(work);
  		break;
  	case IB_CM_APR_RECEIVED:
  		ret = cm_apr_handler(work);
  		break;
  	case IB_CM_TIMEWAIT_EXIT:
  		ret = cm_timewait_handler(work);
  		break;
  	default:
  		ret = -EINVAL;
  		break;
  	}
  	if (ret)
  		cm_free_work(work);
  }
  
  static int cm_establish(struct ib_cm_id *cm_id)
  {
  	struct cm_id_private *cm_id_priv;
  	struct cm_work *work;
  	unsigned long flags;
  	int ret = 0;
  
  	work = kmalloc(sizeof *work, GFP_ATOMIC);
  	if (!work)
  		return -ENOMEM;
  
  	cm_id_priv = container_of(cm_id, struct cm_id_private, id);
  	spin_lock_irqsave(&cm_id_priv->lock, flags);
  	switch (cm_id->state)
  	{
  	case IB_CM_REP_SENT:
  	case IB_CM_MRA_REP_RCVD:
  		cm_id->state = IB_CM_ESTABLISHED;
  		break;
  	case IB_CM_ESTABLISHED:
  		ret = -EISCONN;
  		break;
  	default:
  		ret = -EINVAL;
  		break;
  	}
  	spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  
  	if (ret) {
  		kfree(work);
  		goto out;
  	}
  
  	/*
  	 * The CM worker thread may try to destroy the cm_id before it
  	 * can execute this work item.  To prevent potential deadlock,
  	 * we need to find the cm_id once we're in the context of the
  	 * worker thread, rather than holding a reference on it.
  	 */
  	INIT_DELAYED_WORK(&work->work, cm_work_handler);
  	work->local_id = cm_id->local_id;
  	work->remote_id = cm_id->remote_id;
  	work->mad_recv_wc = NULL;
  	work->cm_event.event = IB_CM_USER_ESTABLISHED;
  	queue_delayed_work(cm.wq, &work->work, 0);
  out:
  	return ret;
  }
  
  static int cm_migrate(struct ib_cm_id *cm_id)
  {
  	struct cm_id_private *cm_id_priv;
  	unsigned long flags;
  	int ret = 0;
  
  	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_ESTABLISHED &&
  	    (cm_id->lap_state == IB_CM_LAP_UNINIT ||
  	     cm_id->lap_state == IB_CM_LAP_IDLE)) {
  		cm_id->lap_state = IB_CM_LAP_IDLE;
  		cm_id_priv->av = cm_id_priv->alt_av;
  	} else
  		ret = -EINVAL;
  	spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  
  	return ret;
  }
  
  int ib_cm_notify(struct ib_cm_id *cm_id, enum ib_event_type event)
  {
  	int ret;
  
  	switch (event) {
  	case IB_EVENT_COMM_EST:
  		ret = cm_establish(cm_id);
  		break;
  	case IB_EVENT_PATH_MIG:
  		ret = cm_migrate(cm_id);
  		break;
  	default:
  		ret = -EINVAL;
  	}
  	return ret;
  }
  EXPORT_SYMBOL(ib_cm_notify);
  
  static void cm_recv_handler(struct ib_mad_agent *mad_agent,
  			    struct ib_mad_recv_wc *mad_recv_wc)
  {
  	struct cm_port *port = mad_agent->context;
  	struct cm_work *work;
  	enum ib_cm_event_type event;
  	u16 attr_id;
  	int paths = 0;
  
  	switch (mad_recv_wc->recv_buf.mad->mad_hdr.attr_id) {
  	case CM_REQ_ATTR_ID:
  		paths = 1 + (((struct cm_req_msg *) mad_recv_wc->recv_buf.mad)->
  						    alt_local_lid != 0);
  		event = IB_CM_REQ_RECEIVED;
  		break;
  	case CM_MRA_ATTR_ID:
  		event = IB_CM_MRA_RECEIVED;
  		break;
  	case CM_REJ_ATTR_ID:
  		event = IB_CM_REJ_RECEIVED;
  		break;
  	case CM_REP_ATTR_ID:
  		event = IB_CM_REP_RECEIVED;
  		break;
  	case CM_RTU_ATTR_ID:
  		event = IB_CM_RTU_RECEIVED;
  		break;
  	case CM_DREQ_ATTR_ID:
  		event = IB_CM_DREQ_RECEIVED;
  		break;
  	case CM_DREP_ATTR_ID:
  		event = IB_CM_DREP_RECEIVED;
  		break;
  	case CM_SIDR_REQ_ATTR_ID:
  		event = IB_CM_SIDR_REQ_RECEIVED;
  		break;
  	case CM_SIDR_REP_ATTR_ID:
  		event = IB_CM_SIDR_REP_RECEIVED;
  		break;
  	case CM_LAP_ATTR_ID:
  		paths = 1;
  		event = IB_CM_LAP_RECEIVED;
  		break;
  	case CM_APR_ATTR_ID:
  		event = IB_CM_APR_RECEIVED;
  		break;
  	default:
  		ib_free_recv_mad(mad_recv_wc);
  		return;
  	}
  
  	attr_id = be16_to_cpu(mad_recv_wc->recv_buf.mad->mad_hdr.attr_id);
  	atomic_long_inc(&port->counter_group[CM_RECV].
  			counter[attr_id - CM_ATTR_ID_OFFSET]);
  
  	work = kmalloc(sizeof *work + sizeof(struct ib_sa_path_rec) * paths,
  		       GFP_KERNEL);
  	if (!work) {
  		ib_free_recv_mad(mad_recv_wc);
  		return;
  	}
  
  	INIT_DELAYED_WORK(&work->work, cm_work_handler);
  	work->cm_event.event = event;
  	work->mad_recv_wc = mad_recv_wc;
  	work->port = port;
  	queue_delayed_work(cm.wq, &work->work, 0);
  }
  
  static int cm_init_qp_init_attr(struct cm_id_private *cm_id_priv,
  				struct ib_qp_attr *qp_attr,
  				int *qp_attr_mask)
  {
  	unsigned long flags;
  	int ret;
  
  	spin_lock_irqsave(&cm_id_priv->lock, flags);
  	switch (cm_id_priv->id.state) {
  	case IB_CM_REQ_SENT:
  	case IB_CM_MRA_REQ_RCVD:
  	case IB_CM_REQ_RCVD:
  	case IB_CM_MRA_REQ_SENT:
  	case IB_CM_REP_RCVD:
  	case IB_CM_MRA_REP_SENT:
  	case IB_CM_REP_SENT:
  	case IB_CM_MRA_REP_RCVD:
  	case IB_CM_ESTABLISHED:
  		*qp_attr_mask = IB_QP_STATE | IB_QP_ACCESS_FLAGS |
  				IB_QP_PKEY_INDEX | IB_QP_PORT;
  		qp_attr->qp_access_flags = IB_ACCESS_REMOTE_WRITE;
  		if (cm_id_priv->responder_resources)
  			qp_attr->qp_access_flags |= IB_ACCESS_REMOTE_READ |
  						    IB_ACCESS_REMOTE_ATOMIC;
  		qp_attr->pkey_index = cm_id_priv->av.pkey_index;
  		qp_attr->port_num = cm_id_priv->av.port->port_num;
  		ret = 0;
  		break;
  	default:
  		ret = -EINVAL;
  		break;
  	}
  	spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  	return ret;
  }
  
  static int cm_init_qp_rtr_attr(struct cm_id_private *cm_id_priv,
  			       struct ib_qp_attr *qp_attr,
  			       int *qp_attr_mask)
  {
  	unsigned long flags;
  	int ret;
  
  	spin_lock_irqsave(&cm_id_priv->lock, flags);
  	switch (cm_id_priv->id.state) {
  	case IB_CM_REQ_RCVD:
  	case IB_CM_MRA_REQ_SENT:
  	case IB_CM_REP_RCVD:
  	case IB_CM_MRA_REP_SENT:
  	case IB_CM_REP_SENT:
  	case IB_CM_MRA_REP_RCVD:
  	case IB_CM_ESTABLISHED:
  		*qp_attr_mask = IB_QP_STATE | IB_QP_AV | IB_QP_PATH_MTU |
  				IB_QP_DEST_QPN | IB_QP_RQ_PSN;
  		qp_attr->ah_attr = cm_id_priv->av.ah_attr;
  		if (!cm_id_priv->av.valid) {
  			spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  			return -EINVAL;
  		}
  		if (cm_id_priv->av.ah_attr.vlan_id != 0xffff) {
  			qp_attr->vlan_id = cm_id_priv->av.ah_attr.vlan_id;
  			*qp_attr_mask |= IB_QP_VID;
  		}
  		if (!is_zero_ether_addr(cm_id_priv->av.smac)) {
  			memcpy(qp_attr->smac, cm_id_priv->av.smac,
  			       sizeof(qp_attr->smac));
  			*qp_attr_mask |= IB_QP_SMAC;
  		}
  		if (cm_id_priv->alt_av.valid) {
  			if (cm_id_priv->alt_av.ah_attr.vlan_id != 0xffff) {
  				qp_attr->alt_vlan_id =
  					cm_id_priv->alt_av.ah_attr.vlan_id;
  				*qp_attr_mask |= IB_QP_ALT_VID;
  			}
  			if (!is_zero_ether_addr(cm_id_priv->alt_av.smac)) {
  				memcpy(qp_attr->alt_smac,
  				       cm_id_priv->alt_av.smac,
  				       sizeof(qp_attr->alt_smac));
  				*qp_attr_mask |= IB_QP_ALT_SMAC;
  			}
  		}
  		qp_attr->path_mtu = cm_id_priv->path_mtu;
  		qp_attr->dest_qp_num = be32_to_cpu(cm_id_priv->remote_qpn);
  		qp_attr->rq_psn = be32_to_cpu(cm_id_priv->rq_psn);
  		if (cm_id_priv->qp_type == IB_QPT_RC ||
  		    cm_id_priv->qp_type == IB_QPT_XRC_TGT) {
  			*qp_attr_mask |= IB_QP_MAX_DEST_RD_ATOMIC |
  					 IB_QP_MIN_RNR_TIMER;
  			qp_attr->max_dest_rd_atomic =
  					cm_id_priv->responder_resources;
  			qp_attr->min_rnr_timer = 0;
  		}
  		if (cm_id_priv->alt_av.ah_attr.dlid) {
  			*qp_attr_mask |= IB_QP_ALT_PATH;
  			qp_attr->alt_port_num = cm_id_priv->alt_av.port->port_num;
  			qp_attr->alt_pkey_index = cm_id_priv->alt_av.pkey_index;
  			qp_attr->alt_timeout = cm_id_priv->alt_av.timeout;
  			qp_attr->alt_ah_attr = cm_id_priv->alt_av.ah_attr;
  		}
  		ret = 0;
  		break;
  	default:
  		ret = -EINVAL;
  		break;
  	}
  	spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  	return ret;
  }
  
  static int cm_init_qp_rts_attr(struct cm_id_private *cm_id_priv,
  			       struct ib_qp_attr *qp_attr,
  			       int *qp_attr_mask)
  {
  	unsigned long flags;
  	int ret;
  
  	spin_lock_irqsave(&cm_id_priv->lock, flags);
  	switch (cm_id_priv->id.state) {
  	/* Allow transition to RTS before sending REP */
  	case IB_CM_REQ_RCVD:
  	case IB_CM_MRA_REQ_SENT:
  
  	case IB_CM_REP_RCVD:
  	case IB_CM_MRA_REP_SENT:
  	case IB_CM_REP_SENT:
  	case IB_CM_MRA_REP_RCVD:
  	case IB_CM_ESTABLISHED:
  		if (cm_id_priv->id.lap_state == IB_CM_LAP_UNINIT) {
  			*qp_attr_mask = IB_QP_STATE | IB_QP_SQ_PSN;
  			qp_attr->sq_psn = be32_to_cpu(cm_id_priv->sq_psn);
  			switch (cm_id_priv->qp_type) {
  			case IB_QPT_RC:
  			case IB_QPT_XRC_INI:
  				*qp_attr_mask |= IB_QP_RETRY_CNT | IB_QP_RNR_RETRY |
  						 IB_QP_MAX_QP_RD_ATOMIC;
  				qp_attr->retry_cnt = cm_id_priv->retry_count;
  				qp_attr->rnr_retry = cm_id_priv->rnr_retry_count;
  				qp_attr->max_rd_atomic = cm_id_priv->initiator_depth;
  				/* fall through */
  			case IB_QPT_XRC_TGT:
  				*qp_attr_mask |= IB_QP_TIMEOUT;
  				qp_attr->timeout = cm_id_priv->av.timeout;
  				break;
  			default:
  				break;
  			}
  			if (cm_id_priv->alt_av.ah_attr.dlid) {
  				*qp_attr_mask |= IB_QP_PATH_MIG_STATE;
  				qp_attr->path_mig_state = IB_MIG_REARM;
  			}
  		} else {
  			*qp_attr_mask = IB_QP_ALT_PATH | IB_QP_PATH_MIG_STATE;
  			qp_attr->alt_port_num = cm_id_priv->alt_av.port->port_num;
  			qp_attr->alt_pkey_index = cm_id_priv->alt_av.pkey_index;
  			qp_attr->alt_timeout = cm_id_priv->alt_av.timeout;
  			qp_attr->alt_ah_attr = cm_id_priv->alt_av.ah_attr;
  			qp_attr->path_mig_state = IB_MIG_REARM;
  		}
  		ret = 0;
  		break;
  	default:
  		ret = -EINVAL;
  		break;
  	}
  	spin_unlock_irqrestore(&cm_id_priv->lock, flags);
  	return ret;
  }
  
  int ib_cm_init_qp_attr(struct ib_cm_id *cm_id,
  		       struct ib_qp_attr *qp_attr,
  		       int *qp_attr_mask)
  {
  	struct cm_id_private *cm_id_priv;
  	int ret;
  
  	cm_id_priv = container_of(cm_id, struct cm_id_private, id);
  	switch (qp_attr->qp_state) {
  	case IB_QPS_INIT:
  		ret = cm_init_qp_init_attr(cm_id_priv, qp_attr, qp_attr_mask);
  		break;
  	case IB_QPS_RTR:
  		ret = cm_init_qp_rtr_attr(cm_id_priv, qp_attr, qp_attr_mask);
  		break;
  	case IB_QPS_RTS:
  		ret = cm_init_qp_rts_attr(cm_id_priv, qp_attr, qp_attr_mask);
  		break;
  	default:
  		ret = -EINVAL;
  		break;
  	}
  	return ret;
  }
  EXPORT_SYMBOL(ib_cm_init_qp_attr);
  
  static void cm_get_ack_delay(struct cm_device *cm_dev)
  {
  	struct ib_device_attr attr;
  
  	if (ib_query_device(cm_dev->ib_device, &attr))
  		cm_dev->ack_delay = 0; /* acks will rely on packet life time */
  	else
  		cm_dev->ack_delay = attr.local_ca_ack_delay;
  }
  
  static ssize_t cm_show_counter(struct kobject *obj, struct attribute *attr,
  			       char *buf)
  {
  	struct cm_counter_group *group;
  	struct cm_counter_attribute *cm_attr;
  
  	group = container_of(obj, struct cm_counter_group, obj);
  	cm_attr = container_of(attr, struct cm_counter_attribute, attr);
  
  	return sprintf(buf, "%ld\n",
  		       atomic_long_read(&group->counter[cm_attr->index]));
  }
  
  static const struct sysfs_ops cm_counter_ops = {
  	.show = cm_show_counter
  };
  
  static struct kobj_type cm_counter_obj_type = {
  	.sysfs_ops = &cm_counter_ops,
  	.default_attrs = cm_counter_default_attrs
  };
  
  static void cm_release_port_obj(struct kobject *obj)
  {
  	struct cm_port *cm_port;
  
  	cm_port = container_of(obj, struct cm_port, port_obj);
  	kfree(cm_port);
  }
  
  static struct kobj_type cm_port_obj_type = {
  	.release = cm_release_port_obj
  };
  
  static char *cm_devnode(struct device *dev, umode_t *mode)
  {
  	if (mode)
  		*mode = 0666;
  	return kasprintf(GFP_KERNEL, "infiniband/%s", dev_name(dev));
  }
  
  struct class cm_class = {
  	.owner   = THIS_MODULE,
  	.name    = "infiniband_cm",
  	.devnode = cm_devnode,
  };
  EXPORT_SYMBOL(cm_class);
  
  static int cm_create_port_fs(struct cm_port *port)
  {
  	int i, ret;
  
  	ret = kobject_init_and_add(&port->port_obj, &cm_port_obj_type,
  				   &port->cm_dev->device->kobj,
  				   "%d", port->port_num);
  	if (ret) {
  		kfree(port);
  		return ret;
  	}
  
  	for (i = 0; i < CM_COUNTER_GROUPS; i++) {
  		ret = kobject_init_and_add(&port->counter_group[i].obj,
  					   &cm_counter_obj_type,
  					   &port->port_obj,
  					   "%s", counter_group_names[i]);
  		if (ret)
  			goto error;
  	}
  
  	return 0;
  
  error:
  	while (i--)
  		kobject_put(&port->counter_group[i].obj);
  	kobject_put(&port->port_obj);
  	return ret;
  
  }
  
  static void cm_remove_port_fs(struct cm_port *port)
  {
  	int i;
  
  	for (i = 0; i < CM_COUNTER_GROUPS; i++)
  		kobject_put(&port->counter_group[i].obj);
  
  	kobject_put(&port->port_obj);
  }
  
  static void cm_add_one(struct ib_device *ib_device)
  {
  	struct cm_device *cm_dev;
  	struct cm_port *port;
  	struct ib_mad_reg_req reg_req = {
  		.mgmt_class = IB_MGMT_CLASS_CM,
  		.mgmt_class_version = IB_CM_CLASS_VERSION
  	};
  	struct ib_port_modify port_modify = {
  		.set_port_cap_mask = IB_PORT_CM_SUP
  	};
  	unsigned long flags;
  	int ret;
  	u8 i;
  
  	if (rdma_node_get_transport(ib_device->node_type) != RDMA_TRANSPORT_IB)
  		return;
  
  	cm_dev = kzalloc(sizeof(*cm_dev) + sizeof(*port) *
  			 ib_device->phys_port_cnt, GFP_KERNEL);
  	if (!cm_dev)
  		return;
  
  	cm_dev->ib_device = ib_device;
  	cm_get_ack_delay(cm_dev);
  
  	cm_dev->device = device_create(&cm_class, &ib_device->dev,
  				       MKDEV(0, 0), NULL,
  				       "%s", ib_device->name);
  	if (IS_ERR(cm_dev->device)) {
  		kfree(cm_dev);
  		return;
  	}
  
  	set_bit(IB_MGMT_METHOD_SEND, reg_req.method_mask);
  	for (i = 1; i <= ib_device->phys_port_cnt; i++) {
  		port = kzalloc(sizeof *port, GFP_KERNEL);
  		if (!port)
  			goto error1;
  
  		cm_dev->port[i-1] = port;
  		port->cm_dev = cm_dev;
  		port->port_num = i;
  
  		ret = cm_create_port_fs(port);
  		if (ret)
  			goto error1;
  
  		port->mad_agent = ib_register_mad_agent(ib_device, i,
  							IB_QPT_GSI,
  							&reg_req,
  							0,
  							cm_send_handler,
  							cm_recv_handler,
  							port);
  		if (IS_ERR(port->mad_agent))
  			goto error2;
  
  		ret = ib_modify_port(ib_device, i, 0, &port_modify);
  		if (ret)
  			goto error3;
  	}
  	ib_set_client_data(ib_device, &cm_client, cm_dev);
  
  	write_lock_irqsave(&cm.device_lock, flags);
  	list_add_tail(&cm_dev->list, &cm.device_list);
  	write_unlock_irqrestore(&cm.device_lock, flags);
  	return;
  
  error3:
  	ib_unregister_mad_agent(port->mad_agent);
  error2:
  	cm_remove_port_fs(port);
  error1:
  	port_modify.set_port_cap_mask = 0;
  	port_modify.clr_port_cap_mask = IB_PORT_CM_SUP;
  	while (--i) {
  		port = cm_dev->port[i-1];
  		ib_modify_port(ib_device, port->port_num, 0, &port_modify);
  		ib_unregister_mad_agent(port->mad_agent);
  		cm_remove_port_fs(port);
  	}
  	device_unregister(cm_dev->device);
  	kfree(cm_dev);
  }
  
  static void cm_remove_one(struct ib_device *ib_device)
  {
  	struct cm_device *cm_dev;
  	struct cm_port *port;
  	struct ib_port_modify port_modify = {
  		.clr_port_cap_mask = IB_PORT_CM_SUP
  	};
  	unsigned long flags;
  	int i;
  
  	cm_dev = ib_get_client_data(ib_device, &cm_client);
  	if (!cm_dev)
  		return;
  
  	write_lock_irqsave(&cm.device_lock, flags);
  	list_del(&cm_dev->list);
  	write_unlock_irqrestore(&cm.device_lock, flags);
  
  	for (i = 1; i <= ib_device->phys_port_cnt; i++) {
  		port = cm_dev->port[i-1];
  		ib_modify_port(ib_device, port->port_num, 0, &port_modify);
  		ib_unregister_mad_agent(port->mad_agent);
  		flush_workqueue(cm.wq);
  		cm_remove_port_fs(port);
  	}
  	device_unregister(cm_dev->device);
  	kfree(cm_dev);
  }
  
  static int __init ib_cm_init(void)
  {
  	int ret;
  
  	memset(&cm, 0, sizeof cm);
  	INIT_LIST_HEAD(&cm.device_list);
  	rwlock_init(&cm.device_lock);
  	spin_lock_init(&cm.lock);
  	cm.listen_service_table = RB_ROOT;
  	cm.listen_service_id = be64_to_cpu(IB_CM_ASSIGN_SERVICE_ID);
  	cm.remote_id_table = RB_ROOT;
  	cm.remote_qp_table = RB_ROOT;
  	cm.remote_sidr_table = RB_ROOT;
  	idr_init(&cm.local_id_table);
  	get_random_bytes(&cm.random_id_operand, sizeof cm.random_id_operand);
  	INIT_LIST_HEAD(&cm.timewait_list);
  
  	ret = class_register(&cm_class);
  	if (ret) {
  		ret = -ENOMEM;
  		goto error1;
  	}
  
  	cm.wq = create_workqueue("ib_cm");
  	if (!cm.wq) {
  		ret = -ENOMEM;
  		goto error2;
  	}
  
  	ret = ib_register_client(&cm_client);
  	if (ret)
  		goto error3;
  
  	return 0;
  error3:
  	destroy_workqueue(cm.wq);
  error2:
  	class_unregister(&cm_class);
  error1:
  	idr_destroy(&cm.local_id_table);
  	return ret;
  }
  
  static void __exit ib_cm_cleanup(void)
  {
  	struct cm_timewait_info *timewait_info, *tmp;
  
  	spin_lock_irq(&cm.lock);
  	list_for_each_entry(timewait_info, &cm.timewait_list, list)
  		cancel_delayed_work(&timewait_info->work.work);
  	spin_unlock_irq(&cm.lock);
  
  	ib_unregister_client(&cm_client);
  	destroy_workqueue(cm.wq);
  
  	list_for_each_entry_safe(timewait_info, tmp, &cm.timewait_list, list) {
  		list_del(&timewait_info->list);
  		kfree(timewait_info);
  	}
  
  	class_unregister(&cm_class);
  	idr_destroy(&cm.local_id_table);
  }
  
  module_init(ib_cm_init);
  module_exit(ib_cm_cleanup);
  
  