text: // SPDX-License-Identifier: GPL-2.0-or-later
  /*******************************************************************************
   * This file contains iSCSI extentions for RDMA (iSER) Verbs
   *
   * (c) Copyright 2013 Datera, Inc.
   *
   * Nicholas A. Bellinger <nab@linux-iscsi.org>
   *
   ****************************************************************************/
  
  #include <linux/string.h>
  #include <linux/module.h>
  #include <linux/scatterlist.h>
  #include <linux/socket.h>
  #include <linux/in.h>
  #include <linux/in6.h>
  #include <rdma/ib_verbs.h>
  #include <rdma/ib_cm.h>
  #include <rdma/rdma_cm.h>
  #include <target/target_core_base.h>
  #include <target/target_core_fabric.h>
  #include <target/iscsi/iscsi_transport.h>
  #include <linux/semaphore.h>
  
  #include "ib_isert.h"
  
  #define	ISERT_MAX_CONN		8
  #define ISER_MAX_RX_CQ_LEN	(ISERT_QP_MAX_RECV_DTOS * ISERT_MAX_CONN)
  #define ISER_MAX_TX_CQ_LEN \
  	((ISERT_QP_MAX_REQ_DTOS + ISCSI_DEF_XMIT_CMDS_MAX) * ISERT_MAX_CONN)
  #define ISER_MAX_CQ_LEN		(ISER_MAX_RX_CQ_LEN + ISER_MAX_TX_CQ_LEN + \
  				 ISERT_MAX_CONN)
  
  static int isert_debug_level;
  module_param_named(debug_level, isert_debug_level, int, 0644);
  MODULE_PARM_DESC(debug_level, "Enable debug tracing if > 0 (default:0)");
  
  static DEFINE_MUTEX(device_list_mutex);
  static LIST_HEAD(device_list);
  static struct workqueue_struct *isert_comp_wq;
  static struct workqueue_struct *isert_release_wq;
  
  static int
  isert_put_response(struct iscsi_conn *conn, struct iscsi_cmd *cmd);
  static int
  isert_login_post_recv(struct isert_conn *isert_conn);
  static int
  isert_rdma_accept(struct isert_conn *isert_conn);
  struct rdma_cm_id *isert_setup_id(struct isert_np *isert_np);
  
  static void isert_release_work(struct work_struct *work);
  static void isert_recv_done(struct ib_cq *cq, struct ib_wc *wc);
  static void isert_send_done(struct ib_cq *cq, struct ib_wc *wc);
  static void isert_login_recv_done(struct ib_cq *cq, struct ib_wc *wc);
  static void isert_login_send_done(struct ib_cq *cq, struct ib_wc *wc);
  
  static inline bool
  isert_prot_cmd(struct isert_conn *conn, struct se_cmd *cmd)
  {
  	return (conn->pi_support &&
  		cmd->prot_op != TARGET_PROT_NORMAL);
  }
  
  
  static void
  isert_qp_event_callback(struct ib_event *e, void *context)
  {
  	struct isert_conn *isert_conn = context;
  
  	isert_err("%s (%d): conn %p\n",
  		  ib_event_msg(e->event), e->event, isert_conn);
  
  	switch (e->event) {
  	case IB_EVENT_COMM_EST:
  		rdma_notify(isert_conn->cm_id, IB_EVENT_COMM_EST);
  		break;
  	case IB_EVENT_QP_LAST_WQE_REACHED:
  		isert_warn("Reached TX IB_EVENT_QP_LAST_WQE_REACHED\n");
  		break;
  	default:
  		break;
  	}
  }
  
  static struct isert_comp *
  isert_comp_get(struct isert_conn *isert_conn)
  {
  	struct isert_device *device = isert_conn->device;
  	struct isert_comp *comp;
  	int i, min = 0;
  
  	mutex_lock(&device_list_mutex);
  	for (i = 0; i < device->comps_used; i++)
  		if (device->comps[i].active_qps <
  		    device->comps[min].active_qps)
  			min = i;
  	comp = &device->comps[min];
  	comp->active_qps++;
  	mutex_unlock(&device_list_mutex);
  
  	isert_info("conn %p, using comp %p min_index: %d\n",
  		   isert_conn, comp, min);
  
  	return comp;
  }
  
  static void
  isert_comp_put(struct isert_comp *comp)
  {
  	mutex_lock(&device_list_mutex);
  	comp->active_qps--;
  	mutex_unlock(&device_list_mutex);
  }
  
  static struct ib_qp *
  isert_create_qp(struct isert_conn *isert_conn,
  		struct isert_comp *comp,
  		struct rdma_cm_id *cma_id)
  {
  	struct isert_device *device = isert_conn->device;
  	struct ib_qp_init_attr attr;
  	int ret;
  
  	memset(&attr, 0, sizeof(struct ib_qp_init_attr));
  	attr.event_handler = isert_qp_event_callback;
  	attr.qp_context = isert_conn;
  	attr.send_cq = comp->cq;
  	attr.recv_cq = comp->cq;
  	attr.cap.max_send_wr = ISERT_QP_MAX_REQ_DTOS + 1;
  	attr.cap.max_recv_wr = ISERT_QP_MAX_RECV_DTOS + 1;
  	attr.cap.max_rdma_ctxs = ISCSI_DEF_XMIT_CMDS_MAX;
  	attr.cap.max_send_sge = device->ib_device->attrs.max_send_sge;
  	attr.cap.max_recv_sge = 1;
  	attr.sq_sig_type = IB_SIGNAL_REQ_WR;
  	attr.qp_type = IB_QPT_RC;
  	if (device->pi_capable)
  		attr.create_flags |= IB_QP_CREATE_INTEGRITY_EN;
  
  	ret = rdma_create_qp(cma_id, device->pd, &attr);
  	if (ret) {
  		isert_err("rdma_create_qp failed for cma_id %d\n", ret);
  		return ERR_PTR(ret);
  	}
  
  	return cma_id->qp;
  }
  
  static int
  isert_conn_setup_qp(struct isert_conn *isert_conn, struct rdma_cm_id *cma_id)
  {
  	struct isert_comp *comp;
  	int ret;
  
  	comp = isert_comp_get(isert_conn);
  	isert_conn->qp = isert_create_qp(isert_conn, comp, cma_id);
  	if (IS_ERR(isert_conn->qp)) {
  		ret = PTR_ERR(isert_conn->qp);
  		goto err;
  	}
  
  	return 0;
  err:
  	isert_comp_put(comp);
  	return ret;
  }
  
  static int
  isert_alloc_rx_descriptors(struct isert_conn *isert_conn)
  {
  	struct isert_device *device = isert_conn->device;
  	struct ib_device *ib_dev = device->ib_device;
  	struct iser_rx_desc *rx_desc;
  	struct ib_sge *rx_sg;
  	u64 dma_addr;
  	int i, j;
  
  	isert_conn->rx_descs = kcalloc(ISERT_QP_MAX_RECV_DTOS,
  				       sizeof(struct iser_rx_desc),
  				       GFP_KERNEL);
  	if (!isert_conn->rx_descs)
  		return -ENOMEM;
  
  	rx_desc = isert_conn->rx_descs;
  
  	for (i = 0; i < ISERT_QP_MAX_RECV_DTOS; i++, rx_desc++)  {
  		dma_addr = ib_dma_map_single(ib_dev, (void *)rx_desc,
  					ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
  		if (ib_dma_mapping_error(ib_dev, dma_addr))
  			goto dma_map_fail;
  
  		rx_desc->dma_addr = dma_addr;
  
  		rx_sg = &rx_desc->rx_sg;
  		rx_sg->addr = rx_desc->dma_addr;
  		rx_sg->length = ISER_RX_PAYLOAD_SIZE;
  		rx_sg->lkey = device->pd->local_dma_lkey;
  		rx_desc->rx_cqe.done = isert_recv_done;
  	}
  
  	return 0;
  
  dma_map_fail:
  	rx_desc = isert_conn->rx_descs;
  	for (j = 0; j < i; j++, rx_desc++) {
  		ib_dma_unmap_single(ib_dev, rx_desc->dma_addr,
  				    ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
  	}
  	kfree(isert_conn->rx_descs);
  	isert_conn->rx_descs = NULL;
  	isert_err("conn %p failed to allocate rx descriptors\n", isert_conn);
  	return -ENOMEM;
  }
  
  static void
  isert_free_rx_descriptors(struct isert_conn *isert_conn)
  {
  	struct ib_device *ib_dev = isert_conn->device->ib_device;
  	struct iser_rx_desc *rx_desc;
  	int i;
  
  	if (!isert_conn->rx_descs)
  		return;
  
  	rx_desc = isert_conn->rx_descs;
  	for (i = 0; i < ISERT_QP_MAX_RECV_DTOS; i++, rx_desc++)  {
  		ib_dma_unmap_single(ib_dev, rx_desc->dma_addr,
  				    ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
  	}
  
  	kfree(isert_conn->rx_descs);
  	isert_conn->rx_descs = NULL;
  }
  
  static void
  isert_free_comps(struct isert_device *device)
  {
  	int i;
  
  	for (i = 0; i < device->comps_used; i++) {
  		struct isert_comp *comp = &device->comps[i];
  
  		if (comp->cq)
  			ib_free_cq(comp->cq);
  	}
  	kfree(device->comps);
  }
  
  static int
  isert_alloc_comps(struct isert_device *device)
  {
  	int i, max_cqe, ret = 0;
  
  	device->comps_used = min(ISERT_MAX_CQ, min_t(int, num_online_cpus(),
  				 device->ib_device->num_comp_vectors));
  
  	isert_info("Using %d CQs, %s supports %d vectors support "
  		   "pi_capable %d\n",
  		   device->comps_used, dev_name(&device->ib_device->dev),
  		   device->ib_device->num_comp_vectors,
  		   device->pi_capable);
  
  	device->comps = kcalloc(device->comps_used, sizeof(struct isert_comp),
  				GFP_KERNEL);
  	if (!device->comps)
  		return -ENOMEM;
  
  	max_cqe = min(ISER_MAX_CQ_LEN, device->ib_device->attrs.max_cqe);
  
  	for (i = 0; i < device->comps_used; i++) {
  		struct isert_comp *comp = &device->comps[i];
  
  		comp->device = device;
  		comp->cq = ib_alloc_cq(device->ib_device, comp, max_cqe, i,
  				IB_POLL_WORKQUEUE);
  		if (IS_ERR(comp->cq)) {
  			isert_err("Unable to allocate cq\n");
  			ret = PTR_ERR(comp->cq);
  			comp->cq = NULL;
  			goto out_cq;
  		}
  	}
  
  	return 0;
  out_cq:
  	isert_free_comps(device);
  	return ret;
  }
  
  static int
  isert_create_device_ib_res(struct isert_device *device)
  {
  	struct ib_device *ib_dev = device->ib_device;
  	int ret;
  
  	isert_dbg("devattr->max_send_sge: %d devattr->max_recv_sge %d\n",
  		  ib_dev->attrs.max_send_sge, ib_dev->attrs.max_recv_sge);
  	isert_dbg("devattr->max_sge_rd: %d\n", ib_dev->attrs.max_sge_rd);
  
  	ret = isert_alloc_comps(device);
  	if (ret)
  		goto out;
  
  	device->pd = ib_alloc_pd(ib_dev, 0);
  	if (IS_ERR(device->pd)) {
  		ret = PTR_ERR(device->pd);
  		isert_err("failed to allocate pd, device %p, ret=%d\n",
  			  device, ret);
  		goto out_cq;
  	}
  
  	/* Check signature cap */
  	device->pi_capable = ib_dev->attrs.device_cap_flags &
  			     IB_DEVICE_INTEGRITY_HANDOVER ? true : false;
  
  	return 0;
  
  out_cq:
  	isert_free_comps(device);
  out:
  	if (ret > 0)
  		ret = -EINVAL;
  	return ret;
  }
  
  static void
  isert_free_device_ib_res(struct isert_device *device)
  {
  	isert_info("device %p\n", device);
  
  	ib_dealloc_pd(device->pd);
  	isert_free_comps(device);
  }
  
  static void
  isert_device_put(struct isert_device *device)
  {
  	mutex_lock(&device_list_mutex);
  	device->refcount--;
  	isert_info("device %p refcount %d\n", device, device->refcount);
  	if (!device->refcount) {
  		isert_free_device_ib_res(device);
  		list_del(&device->dev_node);
  		kfree(device);
  	}
  	mutex_unlock(&device_list_mutex);
  }
  
  static struct isert_device *
  isert_device_get(struct rdma_cm_id *cma_id)
  {
  	struct isert_device *device;
  	int ret;
  
  	mutex_lock(&device_list_mutex);
  	list_for_each_entry(device, &device_list, dev_node) {
  		if (device->ib_device->node_guid == cma_id->device->node_guid) {
  			device->refcount++;
  			isert_info("Found iser device %p refcount %d\n",
  				   device, device->refcount);
  			mutex_unlock(&device_list_mutex);
  			return device;
  		}
  	}
  
  	device = kzalloc(sizeof(struct isert_device), GFP_KERNEL);
  	if (!device) {
  		mutex_unlock(&device_list_mutex);
  		return ERR_PTR(-ENOMEM);
  	}
  
  	INIT_LIST_HEAD(&device->dev_node);
  
  	device->ib_device = cma_id->device;
  	ret = isert_create_device_ib_res(device);
  	if (ret) {
  		kfree(device);
  		mutex_unlock(&device_list_mutex);
  		return ERR_PTR(ret);
  	}
  
  	device->refcount++;
  	list_add_tail(&device->dev_node, &device_list);
  	isert_info("Created a new iser device %p refcount %d\n",
  		   device, device->refcount);
  	mutex_unlock(&device_list_mutex);
  
  	return device;
  }
  
  static void
  isert_init_conn(struct isert_conn *isert_conn)
  {
  	isert_conn->state = ISER_CONN_INIT;
  	INIT_LIST_HEAD(&isert_conn->node);
  	init_completion(&isert_conn->login_comp);
  	init_completion(&isert_conn->login_req_comp);
  	init_waitqueue_head(&isert_conn->rem_wait);
  	kref_init(&isert_conn->kref);
  	mutex_init(&isert_conn->mutex);
  	INIT_WORK(&isert_conn->release_work, isert_release_work);
  }
  
  static void
  isert_free_login_buf(struct isert_conn *isert_conn)
  {
  	struct ib_device *ib_dev = isert_conn->device->ib_device;
  
  	ib_dma_unmap_single(ib_dev, isert_conn->login_rsp_dma,
  			    ISER_RX_PAYLOAD_SIZE, DMA_TO_DEVICE);
  	kfree(isert_conn->login_rsp_buf);
  
  	ib_dma_unmap_single(ib_dev, isert_conn->login_req_dma,
  			    ISER_RX_PAYLOAD_SIZE,
  			    DMA_FROM_DEVICE);
  	kfree(isert_conn->login_req_buf);
  }
  
  static int
  isert_alloc_login_buf(struct isert_conn *isert_conn,
  		      struct ib_device *ib_dev)
  {
  	int ret;
  
  	isert_conn->login_req_buf = kzalloc(sizeof(*isert_conn->login_req_buf),
  			GFP_KERNEL);
  	if (!isert_conn->login_req_buf)
  		return -ENOMEM;
  
  	isert_conn->login_req_dma = ib_dma_map_single(ib_dev,
  				isert_conn->login_req_buf,
  				ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
  	ret = ib_dma_mapping_error(ib_dev, isert_conn->login_req_dma);
  	if (ret) {
  		isert_err("login_req_dma mapping error: %d\n", ret);
  		isert_conn->login_req_dma = 0;
  		goto out_free_login_req_buf;
  	}
  
  	isert_conn->login_rsp_buf = kzalloc(ISER_RX_PAYLOAD_SIZE, GFP_KERNEL);
  	if (!isert_conn->login_rsp_buf) {
  		ret = -ENOMEM;
  		goto out_unmap_login_req_buf;
  	}
  
  	isert_conn->login_rsp_dma = ib_dma_map_single(ib_dev,
  					isert_conn->login_rsp_buf,
  					ISER_RX_PAYLOAD_SIZE, DMA_TO_DEVICE);
  	ret = ib_dma_mapping_error(ib_dev, isert_conn->login_rsp_dma);
  	if (ret) {
  		isert_err("login_rsp_dma mapping error: %d\n", ret);
  		isert_conn->login_rsp_dma = 0;
  		goto out_free_login_rsp_buf;
  	}
  
  	return 0;
  
  out_free_login_rsp_buf:
  	kfree(isert_conn->login_rsp_buf);
  out_unmap_login_req_buf:
  	ib_dma_unmap_single(ib_dev, isert_conn->login_req_dma,
  			    ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
  out_free_login_req_buf:
  	kfree(isert_conn->login_req_buf);
  	return ret;
  }
  
  static void
  isert_set_nego_params(struct isert_conn *isert_conn,
  		      struct rdma_conn_param *param)
  {
  	struct ib_device_attr *attr = &isert_conn->device->ib_device->attrs;
  
  	/* Set max inflight RDMA READ requests */
  	isert_conn->initiator_depth = min_t(u8, param->initiator_depth,
  				attr->max_qp_init_rd_atom);
  	isert_dbg("Using initiator_depth: %u\n", isert_conn->initiator_depth);
  
  	if (param->private_data) {
  		u8 flags = *(u8 *)param->private_data;
  
  		/*
  		 * use remote invalidation if the both initiator
  		 * and the HCA support it
  		 */
  		isert_conn->snd_w_inv = !(flags & ISER_SEND_W_INV_NOT_SUP) &&
  					  (attr->device_cap_flags &
  					   IB_DEVICE_MEM_MGT_EXTENSIONS);
  		if (isert_conn->snd_w_inv)
  			isert_info("Using remote invalidation\n");
  	}
  }
  
  static int
  isert_connect_request(struct rdma_cm_id *cma_id, struct rdma_cm_event *event)
  {
  	struct isert_np *isert_np = cma_id->context;
  	struct iscsi_np *np = isert_np->np;
  	struct isert_conn *isert_conn;
  	struct isert_device *device;
  	int ret = 0;
  
  	spin_lock_bh(&np->np_thread_lock);
  	if (!np->enabled) {
  		spin_unlock_bh(&np->np_thread_lock);
  		isert_dbg("iscsi_np is not enabled, reject connect request\n");
  		return rdma_reject(cma_id, NULL, 0, IB_CM_REJ_CONSUMER_DEFINED);
  	}
  	spin_unlock_bh(&np->np_thread_lock);
  
  	isert_dbg("cma_id: %p, portal: %p\n",
  		 cma_id, cma_id->context);
  
  	isert_conn = kzalloc(sizeof(struct isert_conn), GFP_KERNEL);
  	if (!isert_conn)
  		return -ENOMEM;
  
  	isert_init_conn(isert_conn);
  	isert_conn->cm_id = cma_id;
  
  	ret = isert_alloc_login_buf(isert_conn, cma_id->device);
  	if (ret)
  		goto out;
  
  	device = isert_device_get(cma_id);
  	if (IS_ERR(device)) {
  		ret = PTR_ERR(device);
  		goto out_rsp_dma_map;
  	}
  	isert_conn->device = device;
  
  	isert_set_nego_params(isert_conn, &event->param.conn);
  
  	ret = isert_conn_setup_qp(isert_conn, cma_id);
  	if (ret)
  		goto out_conn_dev;
  
  	ret = isert_login_post_recv(isert_conn);
  	if (ret)
  		goto out_conn_dev;
  
  	ret = isert_rdma_accept(isert_conn);
  	if (ret)
  		goto out_conn_dev;
  
  	mutex_lock(&isert_np->mutex);
  	list_add_tail(&isert_conn->node, &isert_np->accepted);
  	mutex_unlock(&isert_np->mutex);
  
  	return 0;
  
  out_conn_dev:
  	isert_device_put(device);
  out_rsp_dma_map:
  	isert_free_login_buf(isert_conn);
  out:
  	kfree(isert_conn);
  	rdma_reject(cma_id, NULL, 0, IB_CM_REJ_CONSUMER_DEFINED);
  	return ret;
  }
  
  static void
  isert_connect_release(struct isert_conn *isert_conn)
  {
  	struct isert_device *device = isert_conn->device;
  
  	isert_dbg("conn %p\n", isert_conn);
  
  	BUG_ON(!device);
  
  	isert_free_rx_descriptors(isert_conn);
  	if (isert_conn->cm_id &&
  	    !isert_conn->dev_removed)
  		rdma_destroy_id(isert_conn->cm_id);
  
  	if (isert_conn->qp) {
  		struct isert_comp *comp = isert_conn->qp->recv_cq->cq_context;
  
  		isert_comp_put(comp);
  		ib_destroy_qp(isert_conn->qp);
  	}
  
  	if (isert_conn->login_req_buf)
  		isert_free_login_buf(isert_conn);
  
  	isert_device_put(device);
  
  	if (isert_conn->dev_removed)
  		wake_up_interruptible(&isert_conn->rem_wait);
  	else
  		kfree(isert_conn);
  }
  
  static void
  isert_connected_handler(struct rdma_cm_id *cma_id)
  {
  	struct isert_conn *isert_conn = cma_id->qp->qp_context;
  	struct isert_np *isert_np = cma_id->context;
  
  	isert_info("conn %p\n", isert_conn);
  
  	mutex_lock(&isert_conn->mutex);
  	isert_conn->state = ISER_CONN_UP;
  	kref_get(&isert_conn->kref);
  	mutex_unlock(&isert_conn->mutex);
  
  	mutex_lock(&isert_np->mutex);
  	list_move_tail(&isert_conn->node, &isert_np->pending);
  	mutex_unlock(&isert_np->mutex);
  
  	isert_info("np %p: Allow accept_np to continue\n", isert_np);
  	up(&isert_np->sem);
  }
  
  static void
  isert_release_kref(struct kref *kref)
  {
  	struct isert_conn *isert_conn = container_of(kref,
  				struct isert_conn, kref);
  
  	isert_info("conn %p final kref %s/%d\n", isert_conn, current->comm,
  		   current->pid);
  
  	isert_connect_release(isert_conn);
  }
  
  static void
  isert_put_conn(struct isert_conn *isert_conn)
  {
  	kref_put(&isert_conn->kref, isert_release_kref);
  }
  
  static void
  isert_handle_unbound_conn(struct isert_conn *isert_conn)
  {
  	struct isert_np *isert_np = isert_conn->cm_id->context;
  
  	mutex_lock(&isert_np->mutex);
  	if (!list_empty(&isert_conn->node)) {
  		/*
  		 * This means iscsi doesn't know this connection
  		 * so schedule a cleanup ourselves
  		 */
  		list_del_init(&isert_conn->node);
  		isert_put_conn(isert_conn);
  		queue_work(isert_release_wq, &isert_conn->release_work);
  	}
  	mutex_unlock(&isert_np->mutex);
  }
  
  /**
   * isert_conn_terminate() - Initiate connection termination
   * @isert_conn: isert connection struct
   *
   * Notes:
   * In case the connection state is BOUND, move state
   * to TEMINATING and start teardown sequence (rdma_disconnect).
   * In case the connection state is UP, complete flush as well.
   *
   * This routine must be called with mutex held. Thus it is
   * safe to call multiple times.
   */
  static void
  isert_conn_terminate(struct isert_conn *isert_conn)
  {
  	int err;
  
  	if (isert_conn->state >= ISER_CONN_TERMINATING)
  		return;
  
  	isert_info("Terminating conn %p state %d\n",
  		   isert_conn, isert_conn->state);
  	isert_conn->state = ISER_CONN_TERMINATING;
  	err = rdma_disconnect(isert_conn->cm_id);
  	if (err)
  		isert_warn("Failed rdma_disconnect isert_conn %p\n",
  			   isert_conn);
  }
  
  static int
  isert_np_cma_handler(struct isert_np *isert_np,
  		     enum rdma_cm_event_type event)
  {
  	isert_dbg("%s (%d): isert np %p\n",
  		  rdma_event_msg(event), event, isert_np);
  
  	switch (event) {
  	case RDMA_CM_EVENT_DEVICE_REMOVAL:
  		isert_np->cm_id = NULL;
  		break;
  	case RDMA_CM_EVENT_ADDR_CHANGE:
  		isert_np->cm_id = isert_setup_id(isert_np);
  		if (IS_ERR(isert_np->cm_id)) {
  			isert_err("isert np %p setup id failed: %ld\n",
  				  isert_np, PTR_ERR(isert_np->cm_id));
  			isert_np->cm_id = NULL;
  		}
  		break;
  	default:
  		isert_err("isert np %p Unexpected event %d\n",
  			  isert_np, event);
  	}
  
  	return -1;
  }
  
  static int
  isert_disconnected_handler(struct rdma_cm_id *cma_id,
  			   enum rdma_cm_event_type event)
  {
  	struct isert_conn *isert_conn = cma_id->qp->qp_context;
  
  	mutex_lock(&isert_conn->mutex);
  	switch (isert_conn->state) {
  	case ISER_CONN_TERMINATING:
  		break;
  	case ISER_CONN_UP:
  		isert_conn_terminate(isert_conn);
  		ib_drain_qp(isert_conn->qp);
  		isert_handle_unbound_conn(isert_conn);
  		break;
  	case ISER_CONN_BOUND:
  	case ISER_CONN_FULL_FEATURE: /* FALLTHRU */
  		iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
  		break;
  	default:
  		isert_warn("conn %p terminating in state %d\n",
  			   isert_conn, isert_conn->state);
  	}
  	mutex_unlock(&isert_conn->mutex);
  
  	return 0;
  }
  
  static int
  isert_connect_error(struct rdma_cm_id *cma_id)
  {
  	struct isert_conn *isert_conn = cma_id->qp->qp_context;
  
  	ib_drain_qp(isert_conn->qp);
  	list_del_init(&isert_conn->node);
  	isert_conn->cm_id = NULL;
  	isert_put_conn(isert_conn);
  
  	return -1;
  }
  
  static int
  isert_cma_handler(struct rdma_cm_id *cma_id, struct rdma_cm_event *event)
  {
  	struct isert_np *isert_np = cma_id->context;
  	struct isert_conn *isert_conn;
  	int ret = 0;
  
  	isert_info("%s (%d): status %d id %p np %p\n",
  		   rdma_event_msg(event->event), event->event,
  		   event->status, cma_id, cma_id->context);
  
  	if (isert_np->cm_id == cma_id)
  		return isert_np_cma_handler(cma_id->context, event->event);
  
  	switch (event->event) {
  	case RDMA_CM_EVENT_CONNECT_REQUEST:
  		ret = isert_connect_request(cma_id, event);
  		if (ret)
  			isert_err("failed handle connect request %d\n", ret);
  		break;
  	case RDMA_CM_EVENT_ESTABLISHED:
  		isert_connected_handler(cma_id);
  		break;
  	case RDMA_CM_EVENT_ADDR_CHANGE:    /* FALLTHRU */
  	case RDMA_CM_EVENT_DISCONNECTED:   /* FALLTHRU */
  	case RDMA_CM_EVENT_TIMEWAIT_EXIT:  /* FALLTHRU */
  		ret = isert_disconnected_handler(cma_id, event->event);
  		break;
  	case RDMA_CM_EVENT_DEVICE_REMOVAL:
  		isert_conn = cma_id->qp->qp_context;
  		isert_conn->dev_removed = true;
  		isert_disconnected_handler(cma_id, event->event);
  		wait_event_interruptible(isert_conn->rem_wait,
  					 isert_conn->state == ISER_CONN_DOWN);
  		kfree(isert_conn);
  		/*
  		 * return non-zero from the callback to destroy
  		 * the rdma cm id
  		 */
  		return 1;
  	case RDMA_CM_EVENT_REJECTED:
  		isert_info("Connection rejected: %s\n",
  			   rdma_reject_msg(cma_id, event->status));
  		/* fall through */
  	case RDMA_CM_EVENT_UNREACHABLE:
  	case RDMA_CM_EVENT_CONNECT_ERROR:
  		ret = isert_connect_error(cma_id);
  		break;
  	default:
  		isert_err("Unhandled RDMA CMA event: %d\n", event->event);
  		break;
  	}
  
  	return ret;
  }
  
  static int
  isert_post_recvm(struct isert_conn *isert_conn, u32 count)
  {
  	struct ib_recv_wr *rx_wr;
  	int i, ret;
  	struct iser_rx_desc *rx_desc;
  
  	for (rx_wr = isert_conn->rx_wr, i = 0; i < count; i++, rx_wr++) {
  		rx_desc = &isert_conn->rx_descs[i];
  
  		rx_wr->wr_cqe = &rx_desc->rx_cqe;
  		rx_wr->sg_list = &rx_desc->rx_sg;
  		rx_wr->num_sge = 1;
  		rx_wr->next = rx_wr + 1;
  		rx_desc->in_use = false;
  	}
  	rx_wr--;
  	rx_wr->next = NULL; /* mark end of work requests list */
  
  	ret = ib_post_recv(isert_conn->qp, isert_conn->rx_wr, NULL);
  	if (ret)
  		isert_err("ib_post_recv() failed with ret: %d\n", ret);
  
  	return ret;
  }
  
  static int
  isert_post_recv(struct isert_conn *isert_conn, struct iser_rx_desc *rx_desc)
  {
  	struct ib_recv_wr rx_wr;
  	int ret;
  
  	if (!rx_desc->in_use) {
  		/*
  		 * if the descriptor is not in-use we already reposted it
  		 * for recv, so just silently return
  		 */
  		return 0;
  	}
  
  	rx_desc->in_use = false;
  	rx_wr.wr_cqe = &rx_desc->rx_cqe;
  	rx_wr.sg_list = &rx_desc->rx_sg;
  	rx_wr.num_sge = 1;
  	rx_wr.next = NULL;
  
  	ret = ib_post_recv(isert_conn->qp, &rx_wr, NULL);
  	if (ret)
  		isert_err("ib_post_recv() failed with ret: %d\n", ret);
  
  	return ret;
  }
  
  static int
  isert_login_post_send(struct isert_conn *isert_conn, struct iser_tx_desc *tx_desc)
  {
  	struct ib_device *ib_dev = isert_conn->cm_id->device;
  	struct ib_send_wr send_wr;
  	int ret;
  
  	ib_dma_sync_single_for_device(ib_dev, tx_desc->dma_addr,
  				      ISER_HEADERS_LEN, DMA_TO_DEVICE);
  
  	tx_desc->tx_cqe.done = isert_login_send_done;
  
  	send_wr.next	= NULL;
  	send_wr.wr_cqe	= &tx_desc->tx_cqe;
  	send_wr.sg_list	= tx_desc->tx_sg;
  	send_wr.num_sge	= tx_desc->num_sge;
  	send_wr.opcode	= IB_WR_SEND;
  	send_wr.send_flags = IB_SEND_SIGNALED;
  
  	ret = ib_post_send(isert_conn->qp, &send_wr, NULL);
  	if (ret)
  		isert_err("ib_post_send() failed, ret: %d\n", ret);
  
  	return ret;
  }
  
  static void
  __isert_create_send_desc(struct isert_device *device,
  			 struct iser_tx_desc *tx_desc)
  {
  
  	memset(&tx_desc->iser_header, 0, sizeof(struct iser_ctrl));
  	tx_desc->iser_header.flags = ISCSI_CTRL;
  
  	tx_desc->num_sge = 1;
  
  	if (tx_desc->tx_sg[0].lkey != device->pd->local_dma_lkey) {
  		tx_desc->tx_sg[0].lkey = device->pd->local_dma_lkey;
  		isert_dbg("tx_desc %p lkey mismatch, fixing\n", tx_desc);
  	}
  }
  
  static void
  isert_create_send_desc(struct isert_conn *isert_conn,
  		       struct isert_cmd *isert_cmd,
  		       struct iser_tx_desc *tx_desc)
  {
  	struct isert_device *device = isert_conn->device;
  	struct ib_device *ib_dev = device->ib_device;
  
  	ib_dma_sync_single_for_cpu(ib_dev, tx_desc->dma_addr,
  				   ISER_HEADERS_LEN, DMA_TO_DEVICE);
  
  	__isert_create_send_desc(device, tx_desc);
  }
  
  static int
  isert_init_tx_hdrs(struct isert_conn *isert_conn,
  		   struct iser_tx_desc *tx_desc)
  {
  	struct isert_device *device = isert_conn->device;
  	struct ib_device *ib_dev = device->ib_device;
  	u64 dma_addr;
  
  	dma_addr = ib_dma_map_single(ib_dev, (void *)tx_desc,
  			ISER_HEADERS_LEN, DMA_TO_DEVICE);
  	if (ib_dma_mapping_error(ib_dev, dma_addr)) {
  		isert_err("ib_dma_mapping_error() failed\n");
  		return -ENOMEM;
  	}
  
  	tx_desc->dma_addr = dma_addr;
  	tx_desc->tx_sg[0].addr	= tx_desc->dma_addr;
  	tx_desc->tx_sg[0].length = ISER_HEADERS_LEN;
  	tx_desc->tx_sg[0].lkey = device->pd->local_dma_lkey;
  
  	isert_dbg("Setup tx_sg[0].addr: 0x%llx length: %u lkey: 0x%x\n",
  		  tx_desc->tx_sg[0].addr, tx_desc->tx_sg[0].length,
  		  tx_desc->tx_sg[0].lkey);
  
  	return 0;
  }
  
  static void
  isert_init_send_wr(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
  		   struct ib_send_wr *send_wr)
  {
  	struct iser_tx_desc *tx_desc = &isert_cmd->tx_desc;
  
  	tx_desc->tx_cqe.done = isert_send_done;
  	send_wr->wr_cqe = &tx_desc->tx_cqe;
  
  	if (isert_conn->snd_w_inv && isert_cmd->inv_rkey) {
  		send_wr->opcode  = IB_WR_SEND_WITH_INV;
  		send_wr->ex.invalidate_rkey = isert_cmd->inv_rkey;
  	} else {
  		send_wr->opcode = IB_WR_SEND;
  	}
  
  	send_wr->sg_list = &tx_desc->tx_sg[0];
  	send_wr->num_sge = isert_cmd->tx_desc.num_sge;
  	send_wr->send_flags = IB_SEND_SIGNALED;
  }
  
  static int
  isert_login_post_recv(struct isert_conn *isert_conn)
  {
  	struct ib_recv_wr rx_wr;
  	struct ib_sge sge;
  	int ret;
  
  	memset(&sge, 0, sizeof(struct ib_sge));
  	sge.addr = isert_conn->login_req_dma;
  	sge.length = ISER_RX_PAYLOAD_SIZE;
  	sge.lkey = isert_conn->device->pd->local_dma_lkey;
  
  	isert_dbg("Setup sge: addr: %llx length: %d 0x%08x\n",
  		sge.addr, sge.length, sge.lkey);
  
  	isert_conn->login_req_buf->rx_cqe.done = isert_login_recv_done;
  
  	memset(&rx_wr, 0, sizeof(struct ib_recv_wr));
  	rx_wr.wr_cqe = &isert_conn->login_req_buf->rx_cqe;
  	rx_wr.sg_list = &sge;
  	rx_wr.num_sge = 1;
  
  	ret = ib_post_recv(isert_conn->qp, &rx_wr, NULL);
  	if (ret)
  		isert_err("ib_post_recv() failed: %d\n", ret);
  
  	return ret;
  }
  
  static int
  isert_put_login_tx(struct iscsi_conn *conn, struct iscsi_login *login,
  		   u32 length)
  {
  	struct isert_conn *isert_conn = conn->context;
  	struct isert_device *device = isert_conn->device;
  	struct ib_device *ib_dev = device->ib_device;
  	struct iser_tx_desc *tx_desc = &isert_conn->login_tx_desc;
  	int ret;
  
  	__isert_create_send_desc(device, tx_desc);
  
  	memcpy(&tx_desc->iscsi_header, &login->rsp[0],
  	       sizeof(struct iscsi_hdr));
  
  	isert_init_tx_hdrs(isert_conn, tx_desc);
  
  	if (length > 0) {
  		struct ib_sge *tx_dsg = &tx_desc->tx_sg[1];
  
  		ib_dma_sync_single_for_cpu(ib_dev, isert_conn->login_rsp_dma,
  					   length, DMA_TO_DEVICE);
  
  		memcpy(isert_conn->login_rsp_buf, login->rsp_buf, length);
  
  		ib_dma_sync_single_for_device(ib_dev, isert_conn->login_rsp_dma,
  					      length, DMA_TO_DEVICE);
  
  		tx_dsg->addr	= isert_conn->login_rsp_dma;
  		tx_dsg->length	= length;
  		tx_dsg->lkey	= isert_conn->device->pd->local_dma_lkey;
  		tx_desc->num_sge = 2;
  	}
  	if (!login->login_failed) {
  		if (login->login_complete) {
  			ret = isert_alloc_rx_descriptors(isert_conn);
  			if (ret)
  				return ret;
  
  			ret = isert_post_recvm(isert_conn,
  					       ISERT_QP_MAX_RECV_DTOS);
  			if (ret)
  				return ret;
  
  			/* Now we are in FULL_FEATURE phase */
  			mutex_lock(&isert_conn->mutex);
  			isert_conn->state = ISER_CONN_FULL_FEATURE;
  			mutex_unlock(&isert_conn->mutex);
  			goto post_send;
  		}
  
  		ret = isert_login_post_recv(isert_conn);
  		if (ret)
  			return ret;
  	}
  post_send:
  	ret = isert_login_post_send(isert_conn, tx_desc);
  	if (ret)
  		return ret;
  
  	return 0;
  }
  
  static void
  isert_rx_login_req(struct isert_conn *isert_conn)
  {
  	struct iser_rx_desc *rx_desc = isert_conn->login_req_buf;
  	int rx_buflen = isert_conn->login_req_len;
  	struct iscsi_conn *conn = isert_conn->conn;
  	struct iscsi_login *login = conn->conn_login;
  	int size;
  
  	isert_info("conn %p\n", isert_conn);
  
  	WARN_ON_ONCE(!login);
  
  	if (login->first_request) {
  		struct iscsi_login_req *login_req =
  			(struct iscsi_login_req *)&rx_desc->iscsi_header;
  		/*
  		 * Setup the initial iscsi_login values from the leading
  		 * login request PDU.
  		 */
  		login->leading_connection = (!login_req->tsih) ? 1 : 0;
  		login->current_stage =
  			(login_req->flags & ISCSI_FLAG_LOGIN_CURRENT_STAGE_MASK)
  			 >> 2;
  		login->version_min	= login_req->min_version;
  		login->version_max	= login_req->max_version;
  		memcpy(login->isid, login_req->isid, 6);
  		login->cmd_sn		= be32_to_cpu(login_req->cmdsn);
  		login->init_task_tag	= login_req->itt;
  		login->initial_exp_statsn = be32_to_cpu(login_req->exp_statsn);
  		login->cid		= be16_to_cpu(login_req->cid);
  		login->tsih		= be16_to_cpu(login_req->tsih);
  	}
  
  	memcpy(&login->req[0], (void *)&rx_desc->iscsi_header, ISCSI_HDR_LEN);
  
  	size = min(rx_buflen, MAX_KEY_VALUE_PAIRS);
  	isert_dbg("Using login payload size: %d, rx_buflen: %d "
  		  "MAX_KEY_VALUE_PAIRS: %d\n", size, rx_buflen,
  		  MAX_KEY_VALUE_PAIRS);
  	memcpy(login->req_buf, &rx_desc->data[0], size);
  
  	if (login->first_request) {
  		complete(&isert_conn->login_comp);
  		return;
  	}
  	schedule_delayed_work(&conn->login_work, 0);
  }
  
  static struct iscsi_cmd
  *isert_allocate_cmd(struct iscsi_conn *conn, struct iser_rx_desc *rx_desc)
  {
  	struct isert_conn *isert_conn = conn->context;
  	struct isert_cmd *isert_cmd;
  	struct iscsi_cmd *cmd;
  
  	cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
  	if (!cmd) {
  		isert_err("Unable to allocate iscsi_cmd + isert_cmd\n");
  		return NULL;
  	}
  	isert_cmd = iscsit_priv_cmd(cmd);
  	isert_cmd->conn = isert_conn;
  	isert_cmd->iscsi_cmd = cmd;
  	isert_cmd->rx_desc = rx_desc;
  
  	return cmd;
  }
  
  static int
  isert_handle_scsi_cmd(struct isert_conn *isert_conn,
  		      struct isert_cmd *isert_cmd, struct iscsi_cmd *cmd,
  		      struct iser_rx_desc *rx_desc, unsigned char *buf)
  {
  	struct iscsi_conn *conn = isert_conn->conn;
  	struct iscsi_scsi_req *hdr = (struct iscsi_scsi_req *)buf;
  	int imm_data, imm_data_len, unsol_data, sg_nents, rc;
  	bool dump_payload = false;
  	unsigned int data_len;
  
  	rc = iscsit_setup_scsi_cmd(conn, cmd, buf);
  	if (rc < 0)
  		return rc;
  
  	imm_data = cmd->immediate_data;
  	imm_data_len = cmd->first_burst_len;
  	unsol_data = cmd->unsolicited_data;
  	data_len = cmd->se_cmd.data_length;
  
  	if (imm_data && imm_data_len == data_len)
  		cmd->se_cmd.se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
  	rc = iscsit_process_scsi_cmd(conn, cmd, hdr);
  	if (rc < 0) {
  		return 0;
  	} else if (rc > 0) {
  		dump_payload = true;
  		goto sequence_cmd;
  	}
  
  	if (!imm_data)
  		return 0;
  
  	if (imm_data_len != data_len) {
  		sg_nents = max(1UL, DIV_ROUND_UP(imm_data_len, PAGE_SIZE));
  		sg_copy_from_buffer(cmd->se_cmd.t_data_sg, sg_nents,
  				    &rx_desc->data[0], imm_data_len);
  		isert_dbg("Copy Immediate sg_nents: %u imm_data_len: %d\n",
  			  sg_nents, imm_data_len);
  	} else {
  		sg_init_table(&isert_cmd->sg, 1);
  		cmd->se_cmd.t_data_sg = &isert_cmd->sg;
  		cmd->se_cmd.t_data_nents = 1;
  		sg_set_buf(&isert_cmd->sg, &rx_desc->data[0], imm_data_len);
  		isert_dbg("Transfer Immediate imm_data_len: %d\n",
  			  imm_data_len);
  	}
  
  	cmd->write_data_done += imm_data_len;
  
  	if (cmd->write_data_done == cmd->se_cmd.data_length) {
  		spin_lock_bh(&cmd->istate_lock);
  		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
  		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
  		spin_unlock_bh(&cmd->istate_lock);
  	}
  
  sequence_cmd:
  	rc = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
  
  	if (!rc && dump_payload == false && unsol_data)
  		iscsit_set_unsolicited_dataout(cmd);
  	else if (dump_payload && imm_data)
  		target_put_sess_cmd(&cmd->se_cmd);
  
  	return 0;
  }
  
  static int
  isert_handle_iscsi_dataout(struct isert_conn *isert_conn,
  			   struct iser_rx_desc *rx_desc, unsigned char *buf)
  {
  	struct scatterlist *sg_start;
  	struct iscsi_conn *conn = isert_conn->conn;
  	struct iscsi_cmd *cmd = NULL;
  	struct iscsi_data *hdr = (struct iscsi_data *)buf;
  	u32 unsol_data_len = ntoh24(hdr->dlength);
  	int rc, sg_nents, sg_off, page_off;
  
  	rc = iscsit_check_dataout_hdr(conn, buf, &cmd);
  	if (rc < 0)
  		return rc;
  	else if (!cmd)
  		return 0;
  	/*
  	 * FIXME: Unexpected unsolicited_data out
  	 */
  	if (!cmd->unsolicited_data) {
  		isert_err("Received unexpected solicited data payload\n");
  		dump_stack();
  		return -1;
  	}
  
  	isert_dbg("Unsolicited DataOut unsol_data_len: %u, "
  		  "write_data_done: %u, data_length: %u\n",
  		  unsol_data_len,  cmd->write_data_done,
  		  cmd->se_cmd.data_length);
  
  	sg_off = cmd->write_data_done / PAGE_SIZE;
  	sg_start = &cmd->se_cmd.t_data_sg[sg_off];
  	sg_nents = max(1UL, DIV_ROUND_UP(unsol_data_len, PAGE_SIZE));
  	page_off = cmd->write_data_done % PAGE_SIZE;
  	/*
  	 * FIXME: Non page-aligned unsolicited_data out
  	 */
  	if (page_off) {
  		isert_err("unexpected non-page aligned data payload\n");
  		dump_stack();
  		return -1;
  	}
  	isert_dbg("Copying DataOut: sg_start: %p, sg_off: %u "
  		  "sg_nents: %u from %p %u\n", sg_start, sg_off,
  		  sg_nents, &rx_desc->data[0], unsol_data_len);
  
  	sg_copy_from_buffer(sg_start, sg_nents, &rx_desc->data[0],
  			    unsol_data_len);
  
  	rc = iscsit_check_dataout_payload(cmd, hdr, false);
  	if (rc < 0)
  		return rc;
  
  	/*
  	 * multiple data-outs on the same command can arrive -
  	 * so post the buffer before hand
  	 */
  	rc = isert_post_recv(isert_conn, rx_desc);
  	if (rc) {
  		isert_err("ib_post_recv failed with %d\n", rc);
  		return rc;
  	}
  	return 0;
  }
  
  static int
  isert_handle_nop_out(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
  		     struct iscsi_cmd *cmd, struct iser_rx_desc *rx_desc,
  		     unsigned char *buf)
  {
  	struct iscsi_conn *conn = isert_conn->conn;
  	struct iscsi_nopout *hdr = (struct iscsi_nopout *)buf;
  	int rc;
  
  	rc = iscsit_setup_nop_out(conn, cmd, hdr);
  	if (rc < 0)
  		return rc;
  	/*
  	 * FIXME: Add support for NOPOUT payload using unsolicited RDMA payload
  	 */
  
  	return iscsit_process_nop_out(conn, cmd, hdr);
  }
  
  static int
  isert_handle_text_cmd(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
  		      struct iscsi_cmd *cmd, struct iser_rx_desc *rx_desc,
  		      struct iscsi_text *hdr)
  {
  	struct iscsi_conn *conn = isert_conn->conn;
  	u32 payload_length = ntoh24(hdr->dlength);
  	int rc;
  	unsigned char *text_in = NULL;
  
  	rc = iscsit_setup_text_cmd(conn, cmd, hdr);
  	if (rc < 0)
  		return rc;
  
  	if (payload_length) {
  		text_in = kzalloc(payload_length, GFP_KERNEL);
  		if (!text_in)
  			return -ENOMEM;
  	}
  	cmd->text_in_ptr = text_in;
  
  	memcpy(cmd->text_in_ptr, &rx_desc->data[0], payload_length);
  
  	return iscsit_process_text_cmd(conn, cmd, hdr);
  }
  
  static int
  isert_rx_opcode(struct isert_conn *isert_conn, struct iser_rx_desc *rx_desc,
  		uint32_t read_stag, uint64_t read_va,
  		uint32_t write_stag, uint64_t write_va)
  {
  	struct iscsi_hdr *hdr = &rx_desc->iscsi_header;
  	struct iscsi_conn *conn = isert_conn->conn;
  	struct iscsi_cmd *cmd;
  	struct isert_cmd *isert_cmd;
  	int ret = -EINVAL;
  	u8 opcode = (hdr->opcode & ISCSI_OPCODE_MASK);
  
  	if (conn->sess->sess_ops->SessionType &&
  	   (!(opcode & ISCSI_OP_TEXT) || !(opcode & ISCSI_OP_LOGOUT))) {
  		isert_err("Got illegal opcode: 0x%02x in SessionType=Discovery,"
  			  " ignoring\n", opcode);
  		return 0;
  	}
  
  	switch (opcode) {
  	case ISCSI_OP_SCSI_CMD:
  		cmd = isert_allocate_cmd(conn, rx_desc);
  		if (!cmd)
  			break;
  
  		isert_cmd = iscsit_priv_cmd(cmd);
  		isert_cmd->read_stag = read_stag;
  		isert_cmd->read_va = read_va;
  		isert_cmd->write_stag = write_stag;
  		isert_cmd->write_va = write_va;
  		isert_cmd->inv_rkey = read_stag ? read_stag : write_stag;
  
  		ret = isert_handle_scsi_cmd(isert_conn, isert_cmd, cmd,
  					rx_desc, (unsigned char *)hdr);
  		break;
  	case ISCSI_OP_NOOP_OUT:
  		cmd = isert_allocate_cmd(conn, rx_desc);
  		if (!cmd)
  			break;
  
  		isert_cmd = iscsit_priv_cmd(cmd);
  		ret = isert_handle_nop_out(isert_conn, isert_cmd, cmd,
  					   rx_desc, (unsigned char *)hdr);
  		break;
  	case ISCSI_OP_SCSI_DATA_OUT:
  		ret = isert_handle_iscsi_dataout(isert_conn, rx_desc,
  						(unsigned char *)hdr);
  		break;
  	case ISCSI_OP_SCSI_TMFUNC:
  		cmd = isert_allocate_cmd(conn, rx_desc);
  		if (!cmd)
  			break;
  
  		ret = iscsit_handle_task_mgt_cmd(conn, cmd,
  						(unsigned char *)hdr);
  		break;
  	case ISCSI_OP_LOGOUT:
  		cmd = isert_allocate_cmd(conn, rx_desc);
  		if (!cmd)
  			break;
  
  		ret = iscsit_handle_logout_cmd(conn, cmd, (unsigned char *)hdr);
  		break;
  	case ISCSI_OP_TEXT:
  		if (be32_to_cpu(hdr->ttt) != 0xFFFFFFFF)
  			cmd = iscsit_find_cmd_from_itt(conn, hdr->itt);
  		else
  			cmd = isert_allocate_cmd(conn, rx_desc);
  
  		if (!cmd)
  			break;
  
  		isert_cmd = iscsit_priv_cmd(cmd);
  		ret = isert_handle_text_cmd(isert_conn, isert_cmd, cmd,
  					    rx_desc, (struct iscsi_text *)hdr);
  		break;
  	default:
  		isert_err("Got unknown iSCSI OpCode: 0x%02x\n", opcode);
  		dump_stack();
  		break;
  	}
  
  	return ret;
  }
  
  static void
  isert_print_wc(struct ib_wc *wc, const char *type)
  {
  	if (wc->status != IB_WC_WR_FLUSH_ERR)
  		isert_err("%s failure: %s (%d) vend_err %x\n", type,
  			  ib_wc_status_msg(wc->status), wc->status,
  			  wc->vendor_err);
  	else
  		isert_dbg("%s failure: %s (%d)\n", type,
  			  ib_wc_status_msg(wc->status), wc->status);
  }
  
  static void
  isert_recv_done(struct ib_cq *cq, struct ib_wc *wc)
  {
  	struct isert_conn *isert_conn = wc->qp->qp_context;
  	struct ib_device *ib_dev = isert_conn->cm_id->device;
  	struct iser_rx_desc *rx_desc = cqe_to_rx_desc(wc->wr_cqe);
  	struct iscsi_hdr *hdr = &rx_desc->iscsi_header;
  	struct iser_ctrl *iser_ctrl = &rx_desc->iser_header;
  	uint64_t read_va = 0, write_va = 0;
  	uint32_t read_stag = 0, write_stag = 0;
  
  	if (unlikely(wc->status != IB_WC_SUCCESS)) {
  		isert_print_wc(wc, "recv");
  		if (wc->status != IB_WC_WR_FLUSH_ERR)
  			iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
  		return;
  	}
  
  	rx_desc->in_use = true;
  
  	ib_dma_sync_single_for_cpu(ib_dev, rx_desc->dma_addr,
  			ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
  
  	isert_dbg("DMA: 0x%llx, iSCSI opcode: 0x%02x, ITT: 0x%08x, flags: 0x%02x dlen: %d\n",
  		 rx_desc->dma_addr, hdr->opcode, hdr->itt, hdr->flags,
  		 (int)(wc->byte_len - ISER_HEADERS_LEN));
  
  	switch (iser_ctrl->flags & 0xF0) {
  	case ISCSI_CTRL:
  		if (iser_ctrl->flags & ISER_RSV) {
  			read_stag = be32_to_cpu(iser_ctrl->read_stag);
  			read_va = be64_to_cpu(iser_ctrl->read_va);
  			isert_dbg("ISER_RSV: read_stag: 0x%x read_va: 0x%llx\n",
  				  read_stag, (unsigned long long)read_va);
  		}
  		if (iser_ctrl->flags & ISER_WSV) {
  			write_stag = be32_to_cpu(iser_ctrl->write_stag);
  			write_va = be64_to_cpu(iser_ctrl->write_va);
  			isert_dbg("ISER_WSV: write_stag: 0x%x write_va: 0x%llx\n",
  				  write_stag, (unsigned long long)write_va);
  		}
  
  		isert_dbg("ISER ISCSI_CTRL PDU\n");
  		break;
  	case ISER_HELLO:
  		isert_err("iSER Hello message\n");
  		break;
  	default:
  		isert_warn("Unknown iSER hdr flags: 0x%02x\n", iser_ctrl->flags);
  		break;
  	}
  
  	isert_rx_opcode(isert_conn, rx_desc,
  			read_stag, read_va, write_stag, write_va);
  
  	ib_dma_sync_single_for_device(ib_dev, rx_desc->dma_addr,
  			ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
  }
  
  static void
  isert_login_recv_done(struct ib_cq *cq, struct ib_wc *wc)
  {
  	struct isert_conn *isert_conn = wc->qp->qp_context;
  	struct ib_device *ib_dev = isert_conn->device->ib_device;
  
  	if (unlikely(wc->status != IB_WC_SUCCESS)) {
  		isert_print_wc(wc, "login recv");
  		return;
  	}
  
  	ib_dma_sync_single_for_cpu(ib_dev, isert_conn->login_req_dma,
  			ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
  
  	isert_conn->login_req_len = wc->byte_len - ISER_HEADERS_LEN;
  
  	if (isert_conn->conn) {
  		struct iscsi_login *login = isert_conn->conn->conn_login;
  
  		if (login && !login->first_request)
  			isert_rx_login_req(isert_conn);
  	}
  
  	mutex_lock(&isert_conn->mutex);
  	complete(&isert_conn->login_req_comp);
  	mutex_unlock(&isert_conn->mutex);
  
  	ib_dma_sync_single_for_device(ib_dev, isert_conn->login_req_dma,
  				ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
  }
  
  static void
  isert_rdma_rw_ctx_destroy(struct isert_cmd *cmd, struct isert_conn *conn)
  {
  	struct se_cmd *se_cmd = &cmd->iscsi_cmd->se_cmd;
  	enum dma_data_direction dir = target_reverse_dma_direction(se_cmd);
  
  	if (!cmd->rw.nr_ops)
  		return;
  
  	if (isert_prot_cmd(conn, se_cmd)) {
  		rdma_rw_ctx_destroy_signature(&cmd->rw, conn->qp,
  				conn->cm_id->port_num, se_cmd->t_data_sg,
  				se_cmd->t_data_nents, se_cmd->t_prot_sg,
  				se_cmd->t_prot_nents, dir);
  	} else {
  		rdma_rw_ctx_destroy(&cmd->rw, conn->qp, conn->cm_id->port_num,
  				se_cmd->t_data_sg, se_cmd->t_data_nents, dir);
  	}
  
  	cmd->rw.nr_ops = 0;
  }
  
  static void
  isert_put_cmd(struct isert_cmd *isert_cmd, bool comp_err)
  {
  	struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
  	struct isert_conn *isert_conn = isert_cmd->conn;
  	struct iscsi_conn *conn = isert_conn->conn;
  	struct iscsi_text_rsp *hdr;
  
  	isert_dbg("Cmd %p\n", isert_cmd);
  
  	switch (cmd->iscsi_opcode) {
  	case ISCSI_OP_SCSI_CMD:
  		spin_lock_bh(&conn->cmd_lock);
  		if (!list_empty(&cmd->i_conn_node))
  			list_del_init(&cmd->i_conn_node);
  		spin_unlock_bh(&conn->cmd_lock);
  
  		if (cmd->data_direction == DMA_TO_DEVICE) {
  			iscsit_stop_dataout_timer(cmd);
  			/*
  			 * Check for special case during comp_err where
  			 * WRITE_PENDING has been handed off from core,
  			 * but requires an extra target_put_sess_cmd()
  			 * before transport_generic_free_cmd() below.
  			 */
  			if (comp_err &&
  			    cmd->se_cmd.t_state == TRANSPORT_WRITE_PENDING) {
  				struct se_cmd *se_cmd = &cmd->se_cmd;
  
  				target_put_sess_cmd(se_cmd);
  			}
  		}
  
  		isert_rdma_rw_ctx_destroy(isert_cmd, isert_conn);
  		transport_generic_free_cmd(&cmd->se_cmd, 0);
  		break;
  	case ISCSI_OP_SCSI_TMFUNC:
  		spin_lock_bh(&conn->cmd_lock);
  		if (!list_empty(&cmd->i_conn_node))
  			list_del_init(&cmd->i_conn_node);
  		spin_unlock_bh(&conn->cmd_lock);
  
  		transport_generic_free_cmd(&cmd->se_cmd, 0);
  		break;
  	case ISCSI_OP_REJECT:
  	case ISCSI_OP_NOOP_OUT:
  	case ISCSI_OP_TEXT:
  		hdr = (struct iscsi_text_rsp *)&isert_cmd->tx_desc.iscsi_header;
  		/* If the continue bit is on, keep the command alive */
  		if (hdr->flags & ISCSI_FLAG_TEXT_CONTINUE)
  			break;
  
  		spin_lock_bh(&conn->cmd_lock);
  		if (!list_empty(&cmd->i_conn_node))
  			list_del_init(&cmd->i_conn_node);
  		spin_unlock_bh(&conn->cmd_lock);
  
  		/*
  		 * Handle special case for REJECT when iscsi_add_reject*() has
  		 * overwritten the original iscsi_opcode assignment, and the
  		 * associated cmd->se_cmd needs to be released.
  		 */
  		if (cmd->se_cmd.se_tfo != NULL) {
  			isert_dbg("Calling transport_generic_free_cmd for 0x%02x\n",
  				 cmd->iscsi_opcode);
  			transport_generic_free_cmd(&cmd->se_cmd, 0);
  			break;
  		}
  		/* fall through */
  	default:
  		iscsit_release_cmd(cmd);
  		break;
  	}
  }
  
  static void
  isert_unmap_tx_desc(struct iser_tx_desc *tx_desc, struct ib_device *ib_dev)
  {
  	if (tx_desc->dma_addr != 0) {
  		isert_dbg("unmap single for tx_desc->dma_addr\n");
  		ib_dma_unmap_single(ib_dev, tx_desc->dma_addr,
  				    ISER_HEADERS_LEN, DMA_TO_DEVICE);
  		tx_desc->dma_addr = 0;
  	}
  }
  
  static void
  isert_completion_put(struct iser_tx_desc *tx_desc, struct isert_cmd *isert_cmd,
  		     struct ib_device *ib_dev, bool comp_err)
  {
  	if (isert_cmd->pdu_buf_dma != 0) {
  		isert_dbg("unmap single for isert_cmd->pdu_buf_dma\n");
  		ib_dma_unmap_single(ib_dev, isert_cmd->pdu_buf_dma,
  				    isert_cmd->pdu_buf_len, DMA_TO_DEVICE);
  		isert_cmd->pdu_buf_dma = 0;
  	}
  
  	isert_unmap_tx_desc(tx_desc, ib_dev);
  	isert_put_cmd(isert_cmd, comp_err);
  }
  
  static int
  isert_check_pi_status(struct se_cmd *se_cmd, struct ib_mr *sig_mr)
  {
  	struct ib_mr_status mr_status;
  	int ret;
  
  	ret = ib_check_mr_status(sig_mr, IB_MR_CHECK_SIG_STATUS, &mr_status);
  	if (ret) {
  		isert_err("ib_check_mr_status failed, ret %d\n", ret);
  		goto fail_mr_status;
  	}
  
  	if (mr_status.fail_status & IB_MR_CHECK_SIG_STATUS) {
  		u64 sec_offset_err;
  		u32 block_size = se_cmd->se_dev->dev_attrib.block_size + 8;
  
  		switch (mr_status.sig_err.err_type) {
  		case IB_SIG_BAD_GUARD:
  			se_cmd->pi_err = TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED;
  			break;
  		case IB_SIG_BAD_REFTAG:
  			se_cmd->pi_err = TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
  			break;
  		case IB_SIG_BAD_APPTAG:
  			se_cmd->pi_err = TCM_LOGICAL_BLOCK_APP_TAG_CHECK_FAILED;
  			break;
  		}
  		sec_offset_err = mr_status.sig_err.sig_err_offset;
  		do_div(sec_offset_err, block_size);
  		se_cmd->bad_sector = sec_offset_err + se_cmd->t_task_lba;
  
  		isert_err("PI error found type %d at sector 0x%llx "
  			  "expected 0x%x vs actual 0x%x\n",
  			  mr_status.sig_err.err_type,
  			  (unsigned long long)se_cmd->bad_sector,
  			  mr_status.sig_err.expected,
  			  mr_status.sig_err.actual);
  		ret = 1;
  	}
  
  fail_mr_status:
  	return ret;
  }
  
  static void
  isert_rdma_write_done(struct ib_cq *cq, struct ib_wc *wc)
  {
  	struct isert_conn *isert_conn = wc->qp->qp_context;
  	struct isert_device *device = isert_conn->device;
  	struct iser_tx_desc *desc = cqe_to_tx_desc(wc->wr_cqe);
  	struct isert_cmd *isert_cmd = tx_desc_to_cmd(desc);
  	struct se_cmd *cmd = &isert_cmd->iscsi_cmd->se_cmd;
  	int ret = 0;
  
  	if (unlikely(wc->status != IB_WC_SUCCESS)) {
  		isert_print_wc(wc, "rdma write");
  		if (wc->status != IB_WC_WR_FLUSH_ERR)
  			iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
  		isert_completion_put(desc, isert_cmd, device->ib_device, true);
  		return;
  	}
  
  	isert_dbg("Cmd %p\n", isert_cmd);
  
  	ret = isert_check_pi_status(cmd, isert_cmd->rw.reg->mr);
  	isert_rdma_rw_ctx_destroy(isert_cmd, isert_conn);
  
  	if (ret) {
  		/*
  		 * transport_generic_request_failure() expects to have
  		 * plus two references to handle queue-full, so re-add
  		 * one here as target-core will have already dropped
  		 * it after the first isert_put_datain() callback.
  		 */
  		kref_get(&cmd->cmd_kref);
  		transport_generic_request_failure(cmd, cmd->pi_err);
  	} else {
  		/*
  		 * XXX: isert_put_response() failure is not retried.
  		 */
  		ret = isert_put_response(isert_conn->conn, isert_cmd->iscsi_cmd);
  		if (ret)
  			pr_warn_ratelimited("isert_put_response() ret: %d\n", ret);
  	}
  }
  
  static void
  isert_rdma_read_done(struct ib_cq *cq, struct ib_wc *wc)
  {
  	struct isert_conn *isert_conn = wc->qp->qp_context;
  	struct isert_device *device = isert_conn->device;
  	struct iser_tx_desc *desc = cqe_to_tx_desc(wc->wr_cqe);
  	struct isert_cmd *isert_cmd = tx_desc_to_cmd(desc);
  	struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
  	struct se_cmd *se_cmd = &cmd->se_cmd;
  	int ret = 0;
  
  	if (unlikely(wc->status != IB_WC_SUCCESS)) {
  		isert_print_wc(wc, "rdma read");
  		if (wc->status != IB_WC_WR_FLUSH_ERR)
  			iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
  		isert_completion_put(desc, isert_cmd, device->ib_device, true);
  		return;
  	}
  
  	isert_dbg("Cmd %p\n", isert_cmd);
  
  	iscsit_stop_dataout_timer(cmd);
  
  	if (isert_prot_cmd(isert_conn, se_cmd))
  		ret = isert_check_pi_status(se_cmd, isert_cmd->rw.reg->mr);
  	isert_rdma_rw_ctx_destroy(isert_cmd, isert_conn);
  	cmd->write_data_done = 0;
  
  	isert_dbg("Cmd: %p RDMA_READ comp calling execute_cmd\n", isert_cmd);
  	spin_lock_bh(&cmd->istate_lock);
  	cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
  	cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
  	spin_unlock_bh(&cmd->istate_lock);
  
  	/*
  	 * transport_generic_request_failure() will drop the extra
  	 * se_cmd->cmd_kref reference after T10-PI error, and handle
  	 * any non-zero ->queue_status() callback error retries.
  	 */
  	if (ret)
  		transport_generic_request_failure(se_cmd, se_cmd->pi_err);
  	else
  		target_execute_cmd(se_cmd);
  }
  
  static void
  isert_do_control_comp(struct work_struct *work)
  {
  	struct isert_cmd *isert_cmd = container_of(work,
  			struct isert_cmd, comp_work);
  	struct isert_conn *isert_conn = isert_cmd->conn;
  	struct ib_device *ib_dev = isert_conn->cm_id->device;
  	struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
  
  	isert_dbg("Cmd %p i_state %d\n", isert_cmd, cmd->i_state);
  
  	switch (cmd->i_state) {
  	case ISTATE_SEND_TASKMGTRSP:
  		iscsit_tmr_post_handler(cmd, cmd->conn);
  		/* fall through */
  	case ISTATE_SEND_REJECT:
  	case ISTATE_SEND_TEXTRSP:
  		cmd->i_state = ISTATE_SENT_STATUS;
  		isert_completion_put(&isert_cmd->tx_desc, isert_cmd,
  				     ib_dev, false);
  		break;
  	case ISTATE_SEND_LOGOUTRSP:
  		iscsit_logout_post_handler(cmd, cmd->conn);
  		break;
  	default:
  		isert_err("Unknown i_state %d\n", cmd->i_state);
  		dump_stack();
  		break;
  	}
  }
  
  static void
  isert_login_send_done(struct ib_cq *cq, struct ib_wc *wc)
  {
  	struct isert_conn *isert_conn = wc->qp->qp_context;
  	struct ib_device *ib_dev = isert_conn->cm_id->device;
  	struct iser_tx_desc *tx_desc = cqe_to_tx_desc(wc->wr_cqe);
  
  	if (unlikely(wc->status != IB_WC_SUCCESS)) {
  		isert_print_wc(wc, "login send");
  		if (wc->status != IB_WC_WR_FLUSH_ERR)
  			iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
  	}
  
  	isert_unmap_tx_desc(tx_desc, ib_dev);
  }
  
  static void
  isert_send_done(struct ib_cq *cq, struct ib_wc *wc)
  {
  	struct isert_conn *isert_conn = wc->qp->qp_context;
  	struct ib_device *ib_dev = isert_conn->cm_id->device;
  	struct iser_tx_desc *tx_desc = cqe_to_tx_desc(wc->wr_cqe);
  	struct isert_cmd *isert_cmd = tx_desc_to_cmd(tx_desc);
  
  	if (unlikely(wc->status != IB_WC_SUCCESS)) {
  		isert_print_wc(wc, "send");
  		if (wc->status != IB_WC_WR_FLUSH_ERR)
  			iscsit_cause_connection_reinstatement(isert_conn->conn, 0);
  		isert_completion_put(tx_desc, isert_cmd, ib_dev, true);
  		return;
  	}
  
  	isert_dbg("Cmd %p\n", isert_cmd);
  
  	switch (isert_cmd->iscsi_cmd->i_state) {
  	case ISTATE_SEND_TASKMGTRSP:
  	case ISTATE_SEND_LOGOUTRSP:
  	case ISTATE_SEND_REJECT:
  	case ISTATE_SEND_TEXTRSP:
  		isert_unmap_tx_desc(tx_desc, ib_dev);
  
  		INIT_WORK(&isert_cmd->comp_work, isert_do_control_comp);
  		queue_work(isert_comp_wq, &isert_cmd->comp_work);
  		return;
  	default:
  		isert_cmd->iscsi_cmd->i_state = ISTATE_SENT_STATUS;
  		isert_completion_put(tx_desc, isert_cmd, ib_dev, false);
  		break;
  	}
  }
  
  static int
  isert_post_response(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd)
  {
  	int ret;
  
  	ret = isert_post_recv(isert_conn, isert_cmd->rx_desc);
  	if (ret) {
  		isert_err("ib_post_recv failed with %d\n", ret);
  		return ret;
  	}
  
  	ret = ib_post_send(isert_conn->qp, &isert_cmd->tx_desc.send_wr, NULL);
  	if (ret) {
  		isert_err("ib_post_send failed with %d\n", ret);
  		return ret;
  	}
  	return ret;
  }
  
  static int
  isert_put_response(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
  {
  	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
  	struct isert_conn *isert_conn = conn->context;
  	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
  	struct iscsi_scsi_rsp *hdr = (struct iscsi_scsi_rsp *)
  				&isert_cmd->tx_desc.iscsi_header;
  
  	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
  	iscsit_build_rsp_pdu(cmd, conn, true, hdr);
  	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
  	/*
  	 * Attach SENSE DATA payload to iSCSI Response PDU
  	 */
  	if (cmd->se_cmd.sense_buffer &&
  	    ((cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
  	    (cmd->se_cmd.se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
  		struct isert_device *device = isert_conn->device;
  		struct ib_device *ib_dev = device->ib_device;
  		struct ib_sge *tx_dsg = &isert_cmd->tx_desc.tx_sg[1];
  		u32 padding, pdu_len;
  
  		put_unaligned_be16(cmd->se_cmd.scsi_sense_length,
  				   cmd->sense_buffer);
  		cmd->se_cmd.scsi_sense_length += sizeof(__be16);
  
  		padding = -(cmd->se_cmd.scsi_sense_length) & 3;
  		hton24(hdr->dlength, (u32)cmd->se_cmd.scsi_sense_length);
  		pdu_len = cmd->se_cmd.scsi_sense_length + padding;
  
  		isert_cmd->pdu_buf_dma = ib_dma_map_single(ib_dev,
  				(void *)cmd->sense_buffer, pdu_len,
  				DMA_TO_DEVICE);
  		if (ib_dma_mapping_error(ib_dev, isert_cmd->pdu_buf_dma))
  			return -ENOMEM;
  
  		isert_cmd->pdu_buf_len = pdu_len;
  		tx_dsg->addr	= isert_cmd->pdu_buf_dma;
  		tx_dsg->length	= pdu_len;
  		tx_dsg->lkey	= device->pd->local_dma_lkey;
  		isert_cmd->tx_desc.num_sge = 2;
  	}
  
  	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
  
  	isert_dbg("Posting SCSI Response\n");
  
  	return isert_post_response(isert_conn, isert_cmd);
  }
  
  static void
  isert_aborted_task(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
  {
  	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
  	struct isert_conn *isert_conn = conn->context;
  
  	spin_lock_bh(&conn->cmd_lock);
  	if (!list_empty(&cmd->i_conn_node))
  		list_del_init(&cmd->i_conn_node);
  	spin_unlock_bh(&conn->cmd_lock);
  
  	if (cmd->data_direction == DMA_TO_DEVICE)
  		iscsit_stop_dataout_timer(cmd);
  	isert_rdma_rw_ctx_destroy(isert_cmd, isert_conn);
  }
  
  static enum target_prot_op
  isert_get_sup_prot_ops(struct iscsi_conn *conn)
  {
  	struct isert_conn *isert_conn = conn->context;
  	struct isert_device *device = isert_conn->device;
  
  	if (conn->tpg->tpg_attrib.t10_pi) {
  		if (device->pi_capable) {
  			isert_info("conn %p PI offload enabled\n", isert_conn);
  			isert_conn->pi_support = true;
  			return TARGET_PROT_ALL;
  		}
  	}
  
  	isert_info("conn %p PI offload disabled\n", isert_conn);
  	isert_conn->pi_support = false;
  
  	return TARGET_PROT_NORMAL;
  }
  
  static int
  isert_put_nopin(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
  		bool nopout_response)
  {
  	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
  	struct isert_conn *isert_conn = conn->context;
  	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
  
  	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
  	iscsit_build_nopin_rsp(cmd, conn, (struct iscsi_nopin *)
  			       &isert_cmd->tx_desc.iscsi_header,
  			       nopout_response);
  	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
  	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
  
  	isert_dbg("conn %p Posting NOPIN Response\n", isert_conn);
  
  	return isert_post_response(isert_conn, isert_cmd);
  }
  
  static int
  isert_put_logout_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
  {
  	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
  	struct isert_conn *isert_conn = conn->context;
  	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
  
  	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
  	iscsit_build_logout_rsp(cmd, conn, (struct iscsi_logout_rsp *)
  				&isert_cmd->tx_desc.iscsi_header);
  	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
  	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
  
  	isert_dbg("conn %p Posting Logout Response\n", isert_conn);
  
  	return isert_post_response(isert_conn, isert_cmd);
  }
  
  static int
  isert_put_tm_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
  {
  	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
  	struct isert_conn *isert_conn = conn->context;
  	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
  
  	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
  	iscsit_build_task_mgt_rsp(cmd, conn, (struct iscsi_tm_rsp *)
  				  &isert_cmd->tx_desc.iscsi_header);
  	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
  	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
  
  	isert_dbg("conn %p Posting Task Management Response\n", isert_conn);
  
  	return isert_post_response(isert_conn, isert_cmd);
  }
  
  static int
  isert_put_reject(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
  {
  	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
  	struct isert_conn *isert_conn = conn->context;
  	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
  	struct isert_device *device = isert_conn->device;
  	struct ib_device *ib_dev = device->ib_device;
  	struct ib_sge *tx_dsg = &isert_cmd->tx_desc.tx_sg[1];
  	struct iscsi_reject *hdr =
  		(struct iscsi_reject *)&isert_cmd->tx_desc.iscsi_header;
  
  	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
  	iscsit_build_reject(cmd, conn, hdr);
  	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
  
  	hton24(hdr->dlength, ISCSI_HDR_LEN);
  	isert_cmd->pdu_buf_dma = ib_dma_map_single(ib_dev,
  			(void *)cmd->buf_ptr, ISCSI_HDR_LEN,
  			DMA_TO_DEVICE);
  	if (ib_dma_mapping_error(ib_dev, isert_cmd->pdu_buf_dma))
  		return -ENOMEM;
  	isert_cmd->pdu_buf_len = ISCSI_HDR_LEN;
  	tx_dsg->addr	= isert_cmd->pdu_buf_dma;
  	tx_dsg->length	= ISCSI_HDR_LEN;
  	tx_dsg->lkey	= device->pd->local_dma_lkey;
  	isert_cmd->tx_desc.num_sge = 2;
  
  	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
  
  	isert_dbg("conn %p Posting Reject\n", isert_conn);
  
  	return isert_post_response(isert_conn, isert_cmd);
  }
  
  static int
  isert_put_text_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
  {
  	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
  	struct isert_conn *isert_conn = conn->context;
  	struct ib_send_wr *send_wr = &isert_cmd->tx_desc.send_wr;
  	struct iscsi_text_rsp *hdr =
  		(struct iscsi_text_rsp *)&isert_cmd->tx_desc.iscsi_header;
  	u32 txt_rsp_len;
  	int rc;
  
  	isert_create_send_desc(isert_conn, isert_cmd, &isert_cmd->tx_desc);
  	rc = iscsit_build_text_rsp(cmd, conn, hdr, ISCSI_INFINIBAND);
  	if (rc < 0)
  		return rc;
  
  	txt_rsp_len = rc;
  	isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
  
  	if (txt_rsp_len) {
  		struct isert_device *device = isert_conn->device;
  		struct ib_device *ib_dev = device->ib_device;
  		struct ib_sge *tx_dsg = &isert_cmd->tx_desc.tx_sg[1];
  		void *txt_rsp_buf = cmd->buf_ptr;
  
  		isert_cmd->pdu_buf_dma = ib_dma_map_single(ib_dev,
  				txt_rsp_buf, txt_rsp_len, DMA_TO_DEVICE);
  		if (ib_dma_mapping_error(ib_dev, isert_cmd->pdu_buf_dma))
  			return -ENOMEM;
  
  		isert_cmd->pdu_buf_len = txt_rsp_len;
  		tx_dsg->addr	= isert_cmd->pdu_buf_dma;
  		tx_dsg->length	= txt_rsp_len;
  		tx_dsg->lkey	= device->pd->local_dma_lkey;
  		isert_cmd->tx_desc.num_sge = 2;
  	}
  	isert_init_send_wr(isert_conn, isert_cmd, send_wr);
  
  	isert_dbg("conn %p Text Response\n", isert_conn);
  
  	return isert_post_response(isert_conn, isert_cmd);
  }
  
  static inline void
  isert_set_dif_domain(struct se_cmd *se_cmd, struct ib_sig_domain *domain)
  {
  	domain->sig_type = IB_SIG_TYPE_T10_DIF;
  	domain->sig.dif.bg_type = IB_T10DIF_CRC;
  	domain->sig.dif.pi_interval = se_cmd->se_dev->dev_attrib.block_size;
  	domain->sig.dif.ref_tag = se_cmd->reftag_seed;
  	/*
  	 * At the moment we hard code those, but if in the future
  	 * the target core would like to use it, we will take it
  	 * from se_cmd.
  	 */
  	domain->sig.dif.apptag_check_mask = 0xffff;
  	domain->sig.dif.app_escape = true;
  	domain->sig.dif.ref_escape = true;
  	if (se_cmd->prot_type == TARGET_DIF_TYPE1_PROT ||
  	    se_cmd->prot_type == TARGET_DIF_TYPE2_PROT)
  		domain->sig.dif.ref_remap = true;
  };
  
  static int
  isert_set_sig_attrs(struct se_cmd *se_cmd, struct ib_sig_attrs *sig_attrs)
  {
  	memset(sig_attrs, 0, sizeof(*sig_attrs));
  
  	switch (se_cmd->prot_op) {
  	case TARGET_PROT_DIN_INSERT:
  	case TARGET_PROT_DOUT_STRIP:
  		sig_attrs->mem.sig_type = IB_SIG_TYPE_NONE;
  		isert_set_dif_domain(se_cmd, &sig_attrs->wire);
  		break;
  	case TARGET_PROT_DOUT_INSERT:
  	case TARGET_PROT_DIN_STRIP:
  		sig_attrs->wire.sig_type = IB_SIG_TYPE_NONE;
  		isert_set_dif_domain(se_cmd, &sig_attrs->mem);
  		break;
  	case TARGET_PROT_DIN_PASS:
  	case TARGET_PROT_DOUT_PASS:
  		isert_set_dif_domain(se_cmd, &sig_attrs->wire);
  		isert_set_dif_domain(se_cmd, &sig_attrs->mem);
  		break;
  	default:
  		isert_err("Unsupported PI operation %d\n", se_cmd->prot_op);
  		return -EINVAL;
  	}
  
  	if (se_cmd->prot_checks & TARGET_DIF_CHECK_GUARD)
  		sig_attrs->check_mask |= IB_SIG_CHECK_GUARD;
  	if (se_cmd->prot_checks & TARGET_DIF_CHECK_APPTAG)
  		sig_attrs->check_mask |= IB_SIG_CHECK_APPTAG;
  	if (se_cmd->prot_checks & TARGET_DIF_CHECK_REFTAG)
  		sig_attrs->check_mask |= IB_SIG_CHECK_REFTAG;
  
  	return 0;
  }
  
  static int
  isert_rdma_rw_ctx_post(struct isert_cmd *cmd, struct isert_conn *conn,
  		struct ib_cqe *cqe, struct ib_send_wr *chain_wr)
  {
  	struct se_cmd *se_cmd = &cmd->iscsi_cmd->se_cmd;
  	enum dma_data_direction dir = target_reverse_dma_direction(se_cmd);
  	u8 port_num = conn->cm_id->port_num;
  	u64 addr;
  	u32 rkey, offset;
  	int ret;
  
  	if (cmd->ctx_init_done)
  		goto rdma_ctx_post;
  
  	if (dir == DMA_FROM_DEVICE) {
  		addr = cmd->write_va;
  		rkey = cmd->write_stag;
  		offset = cmd->iscsi_cmd->write_data_done;
  	} else {
  		addr = cmd->read_va;
  		rkey = cmd->read_stag;
  		offset = 0;
  	}
  
  	if (isert_prot_cmd(conn, se_cmd)) {
  		struct ib_sig_attrs sig_attrs;
  
  		ret = isert_set_sig_attrs(se_cmd, &sig_attrs);
  		if (ret)
  			return ret;
  
  		WARN_ON_ONCE(offset);
  		ret = rdma_rw_ctx_signature_init(&cmd->rw, conn->qp, port_num,
  				se_cmd->t_data_sg, se_cmd->t_data_nents,
  				se_cmd->t_prot_sg, se_cmd->t_prot_nents,
  				&sig_attrs, addr, rkey, dir);
  	} else {
  		ret = rdma_rw_ctx_init(&cmd->rw, conn->qp, port_num,
  				se_cmd->t_data_sg, se_cmd->t_data_nents,
  				offset, addr, rkey, dir);
  	}
  
  	if (ret < 0) {
  		isert_err("Cmd: %p failed to prepare RDMA res\n", cmd);
  		return ret;
  	}
  
  	cmd->ctx_init_done = true;
  
  rdma_ctx_post:
  	ret = rdma_rw_ctx_post(&cmd->rw, conn->qp, port_num, cqe, chain_wr);
  	if (ret < 0)
  		isert_err("Cmd: %p failed to post RDMA res\n", cmd);
  	return ret;
  }
  
  static int
  isert_put_datain(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
  {
  	struct se_cmd *se_cmd = &cmd->se_cmd;
  	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
  	struct isert_conn *isert_conn = conn->context;
  	struct ib_cqe *cqe = NULL;
  	struct ib_send_wr *chain_wr = NULL;
  	int rc;
  
  	isert_dbg("Cmd: %p RDMA_WRITE data_length: %u\n",
  		 isert_cmd, se_cmd->data_length);
  
  	if (isert_prot_cmd(isert_conn, se_cmd)) {
  		isert_cmd->tx_desc.tx_cqe.done = isert_rdma_write_done;
  		cqe = &isert_cmd->tx_desc.tx_cqe;
  	} else {
  		/*
  		 * Build isert_conn->tx_desc for iSCSI response PDU and attach
  		 */
  		isert_create_send_desc(isert_conn, isert_cmd,
  				       &isert_cmd->tx_desc);
  		iscsit_build_rsp_pdu(cmd, conn, true, (struct iscsi_scsi_rsp *)
  				     &isert_cmd->tx_desc.iscsi_header);
  		isert_init_tx_hdrs(isert_conn, &isert_cmd->tx_desc);
  		isert_init_send_wr(isert_conn, isert_cmd,
  				   &isert_cmd->tx_desc.send_wr);
  
  		rc = isert_post_recv(isert_conn, isert_cmd->rx_desc);
  		if (rc) {
  			isert_err("ib_post_recv failed with %d\n", rc);
  			return rc;
  		}
  
  		chain_wr = &isert_cmd->tx_desc.send_wr;
  	}
  
  	rc = isert_rdma_rw_ctx_post(isert_cmd, isert_conn, cqe, chain_wr);
  	isert_dbg("Cmd: %p posted RDMA_WRITE for iSER Data READ rc: %d\n",
  		  isert_cmd, rc);
  	return rc;
  }
  
  static int
  isert_get_dataout(struct iscsi_conn *conn, struct iscsi_cmd *cmd, bool recovery)
  {
  	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
  	int ret;
  
  	isert_dbg("Cmd: %p RDMA_READ data_length: %u write_data_done: %u\n",
  		 isert_cmd, cmd->se_cmd.data_length, cmd->write_data_done);
  
  	isert_cmd->tx_desc.tx_cqe.done = isert_rdma_read_done;
  	ret = isert_rdma_rw_ctx_post(isert_cmd, conn->context,
  				     &isert_cmd->tx_desc.tx_cqe, NULL);
  
  	isert_dbg("Cmd: %p posted RDMA_READ memory for ISER Data WRITE rc: %d\n",
  		 isert_cmd, ret);
  	return ret;
  }
  
  static int
  isert_immediate_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
  {
  	struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
  	int ret = 0;
  
  	switch (state) {
  	case ISTATE_REMOVE:
  		spin_lock_bh(&conn->cmd_lock);
  		list_del_init(&cmd->i_conn_node);
  		spin_unlock_bh(&conn->cmd_lock);
  		isert_put_cmd(isert_cmd, true);
  		break;
  	case ISTATE_SEND_NOPIN_WANT_RESPONSE:
  		ret = isert_put_nopin(cmd, conn, false);
  		break;
  	default:
  		isert_err("Unknown immediate state: 0x%02x\n", state);
  		ret = -EINVAL;
  		break;
  	}
  
  	return ret;
  }
  
  static int
  isert_response_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
  {
  	struct isert_conn *isert_conn = conn->context;
  	int ret;
  
  	switch (state) {
  	case ISTATE_SEND_LOGOUTRSP:
  		ret = isert_put_logout_rsp(cmd, conn);
  		if (!ret)
  			isert_conn->logout_posted = true;
  		break;
  	case ISTATE_SEND_NOPIN:
  		ret = isert_put_nopin(cmd, conn, true);
  		break;
  	case ISTATE_SEND_TASKMGTRSP:
  		ret = isert_put_tm_rsp(cmd, conn);
  		break;
  	case ISTATE_SEND_REJECT:
  		ret = isert_put_reject(cmd, conn);
  		break;
  	case ISTATE_SEND_TEXTRSP:
  		ret = isert_put_text_rsp(cmd, conn);
  		break;
  	case ISTATE_SEND_STATUS:
  		/*
  		 * Special case for sending non GOOD SCSI status from TX thread
  		 * context during pre se_cmd excecution failure.
  		 */
  		ret = isert_put_response(conn, cmd);
  		break;
  	default:
  		isert_err("Unknown response state: 0x%02x\n", state);
  		ret = -EINVAL;
  		break;
  	}
  
  	return ret;
  }
  
  struct rdma_cm_id *
  isert_setup_id(struct isert_np *isert_np)
  {
  	struct iscsi_np *np = isert_np->np;
  	struct rdma_cm_id *id;
  	struct sockaddr *sa;
  	int ret;
  
  	sa = (struct sockaddr *)&np->np_sockaddr;
  	isert_dbg("ksockaddr: %p, sa: %p\n", &np->np_sockaddr, sa);
  
  	id = rdma_create_id(&init_net, isert_cma_handler, isert_np,
  			    RDMA_PS_TCP, IB_QPT_RC);
  	if (IS_ERR(id)) {
  		isert_err("rdma_create_id() failed: %ld\n", PTR_ERR(id));
  		ret = PTR_ERR(id);
  		goto out;
  	}
  	isert_dbg("id %p context %p\n", id, id->context);
  
  	ret = rdma_bind_addr(id, sa);
  	if (ret) {
  		isert_err("rdma_bind_addr() failed: %d\n", ret);
  		goto out_id;
  	}
  
  	ret = rdma_listen(id, 0);
  	if (ret) {
  		isert_err("rdma_listen() failed: %d\n", ret);
  		goto out_id;
  	}
  
  	return id;
  out_id:
  	rdma_destroy_id(id);
  out:
  	return ERR_PTR(ret);
  }
  
  static int
  isert_setup_np(struct iscsi_np *np,
  	       struct sockaddr_storage *ksockaddr)
  {
  	struct isert_np *isert_np;
  	struct rdma_cm_id *isert_lid;
  	int ret;
  
  	isert_np = kzalloc(sizeof(struct isert_np), GFP_KERNEL);
  	if (!isert_np)
  		return -ENOMEM;
  
  	sema_init(&isert_np->sem, 0);
  	mutex_init(&isert_np->mutex);
  	INIT_LIST_HEAD(&isert_np->accepted);
  	INIT_LIST_HEAD(&isert_np->pending);
  	isert_np->np = np;
  
  	/*
  	 * Setup the np->np_sockaddr from the passed sockaddr setup
  	 * in iscsi_target_configfs.c code..
  	 */
  	memcpy(&np->np_sockaddr, ksockaddr,
  	       sizeof(struct sockaddr_storage));
  
  	isert_lid = isert_setup_id(isert_np);
  	if (IS_ERR(isert_lid)) {
  		ret = PTR_ERR(isert_lid);
  		goto out;
  	}
  
  	isert_np->cm_id = isert_lid;
  	np->np_context = isert_np;
  
  	return 0;
  
  out:
  	kfree(isert_np);
  
  	return ret;
  }
  
  static int
  isert_rdma_accept(struct isert_conn *isert_conn)
  {
  	struct rdma_cm_id *cm_id = isert_conn->cm_id;
  	struct rdma_conn_param cp;
  	int ret;
  	struct iser_cm_hdr rsp_hdr;
  
  	memset(&cp, 0, sizeof(struct rdma_conn_param));
  	cp.initiator_depth = isert_conn->initiator_depth;
  	cp.retry_count = 7;
  	cp.rnr_retry_count = 7;
  
  	memset(&rsp_hdr, 0, sizeof(rsp_hdr));
  	rsp_hdr.flags = ISERT_ZBVA_NOT_USED;
  	if (!isert_conn->snd_w_inv)
  		rsp_hdr.flags = rsp_hdr.flags | ISERT_SEND_W_INV_NOT_USED;
  	cp.private_data = (void *)&rsp_hdr;
  	cp.private_data_len = sizeof(rsp_hdr);
  
  	ret = rdma_accept(cm_id, &cp);
  	if (ret) {
  		isert_err("rdma_accept() failed with: %d\n", ret);
  		return ret;
  	}
  
  	return 0;
  }
  
  static int
  isert_get_login_rx(struct iscsi_conn *conn, struct iscsi_login *login)
  {
  	struct isert_conn *isert_conn = conn->context;
  	int ret;
  
  	isert_info("before login_req comp conn: %p\n", isert_conn);
  	ret = wait_for_completion_interruptible(&isert_conn->login_req_comp);
  	if (ret) {
  		isert_err("isert_conn %p interrupted before got login req\n",
  			  isert_conn);
  		return ret;
  	}
  	reinit_completion(&isert_conn->login_req_comp);
  
  	/*
  	 * For login requests after the first PDU, isert_rx_login_req() will
  	 * kick schedule_delayed_work(&conn->login_work) as the packet is
  	 * received, which turns this callback from iscsi_target_do_login_rx()
  	 * into a NOP.
  	 */
  	if (!login->first_request)
  		return 0;
  
  	isert_rx_login_req(isert_conn);
  
  	isert_info("before login_comp conn: %p\n", conn);
  	ret = wait_for_completion_interruptible(&isert_conn->login_comp);
  	if (ret)
  		return ret;
  
  	isert_info("processing login->req: %p\n", login->req);
  
  	return 0;
  }
  
  static void
  isert_set_conn_info(struct iscsi_np *np, struct iscsi_conn *conn,
  		    struct isert_conn *isert_conn)
  {
  	struct rdma_cm_id *cm_id = isert_conn->cm_id;
  	struct rdma_route *cm_route = &cm_id->route;
  
  	conn->login_family = np->np_sockaddr.ss_family;
  
  	conn->login_sockaddr = cm_route->addr.dst_addr;
  	conn->local_sockaddr = cm_route->addr.src_addr;
  }
  
  static int
  isert_accept_np(struct iscsi_np *np, struct iscsi_conn *conn)
  {
  	struct isert_np *isert_np = np->np_context;
  	struct isert_conn *isert_conn;
  	int ret;
  
  accept_wait:
  	ret = down_interruptible(&isert_np->sem);
  	if (ret)
  		return -ENODEV;
  
  	spin_lock_bh(&np->np_thread_lock);
  	if (np->np_thread_state >= ISCSI_NP_THREAD_RESET) {
  		spin_unlock_bh(&np->np_thread_lock);
  		isert_dbg("np_thread_state %d\n",
  			 np->np_thread_state);
  		/**
  		 * No point in stalling here when np_thread
  		 * is in state RESET/SHUTDOWN/EXIT - bail
  		 **/
  		return -ENODEV;
  	}
  	spin_unlock_bh(&np->np_thread_lock);
  
  	mutex_lock(&isert_np->mutex);
  	if (list_empty(&isert_np->pending)) {
  		mutex_unlock(&isert_np->mutex);
  		goto accept_wait;
  	}
  	isert_conn = list_first_entry(&isert_np->pending,
  			struct isert_conn, node);
  	list_del_init(&isert_conn->node);
  	mutex_unlock(&isert_np->mutex);
  
  	conn->context = isert_conn;
  	isert_conn->conn = conn;
  	isert_conn->state = ISER_CONN_BOUND;
  
  	isert_set_conn_info(np, conn, isert_conn);
  
  	isert_dbg("Processing isert_conn: %p\n", isert_conn);
  
  	return 0;
  }
  
  static void
  isert_free_np(struct iscsi_np *np)
  {
  	struct isert_np *isert_np = np->np_context;
  	struct isert_conn *isert_conn, *n;
  
  	if (isert_np->cm_id)
  		rdma_destroy_id(isert_np->cm_id);
  
  	/*
  	 * FIXME: At this point we don't have a good way to insure
  	 * that at this point we don't have hanging connections that
  	 * completed RDMA establishment but didn't start iscsi login
  	 * process. So work-around this by cleaning up what ever piled
  	 * up in accepted and pending lists.
  	 */
  	mutex_lock(&isert_np->mutex);
  	if (!list_empty(&isert_np->pending)) {
  		isert_info("Still have isert pending connections\n");
  		list_for_each_entry_safe(isert_conn, n,
  					 &isert_np->pending,
  					 node) {
  			isert_info("cleaning isert_conn %p state (%d)\n",
  				   isert_conn, isert_conn->state);
  			isert_connect_release(isert_conn);
  		}
  	}
  
  	if (!list_empty(&isert_np->accepted)) {
  		isert_info("Still have isert accepted connections\n");
  		list_for_each_entry_safe(isert_conn, n,
  					 &isert_np->accepted,
  					 node) {
  			isert_info("cleaning isert_conn %p state (%d)\n",
  				   isert_conn, isert_conn->state);
  			isert_connect_release(isert_conn);
  		}
  	}
  	mutex_unlock(&isert_np->mutex);
  
  	np->np_context = NULL;
  	kfree(isert_np);
  }
  
  static void isert_release_work(struct work_struct *work)
  {
  	struct isert_conn *isert_conn = container_of(work,
  						     struct isert_conn,
  						     release_work);
  
  	isert_info("Starting release conn %p\n", isert_conn);
  
  	mutex_lock(&isert_conn->mutex);
  	isert_conn->state = ISER_CONN_DOWN;
  	mutex_unlock(&isert_conn->mutex);
  
  	isert_info("Destroying conn %p\n", isert_conn);
  	isert_put_conn(isert_conn);
  }
  
  static void
  isert_wait4logout(struct isert_conn *isert_conn)
  {
  	struct iscsi_conn *conn = isert_conn->conn;
  
  	isert_info("conn %p\n", isert_conn);
  
  	if (isert_conn->logout_posted) {
  		isert_info("conn %p wait for conn_logout_comp\n", isert_conn);
  		wait_for_completion_timeout(&conn->conn_logout_comp,
  					    SECONDS_FOR_LOGOUT_COMP * HZ);
  	}
  }
  
  static void
  isert_wait4cmds(struct iscsi_conn *conn)
  {
  	isert_info("iscsi_conn %p\n", conn);
  
  	if (conn->sess) {
  		target_sess_cmd_list_set_waiting(conn->sess->se_sess);
  		target_wait_for_sess_cmds(conn->sess->se_sess);
  	}
  }
  
  /**
   * isert_put_unsol_pending_cmds() - Drop commands waiting for
   *     unsolicitate dataout
   * @conn:    iscsi connection
   *
   * We might still have commands that are waiting for unsolicited
   * dataouts messages. We must put the extra reference on those
   * before blocking on the target_wait_for_session_cmds
   */
  static void
  isert_put_unsol_pending_cmds(struct iscsi_conn *conn)
  {
  	struct iscsi_cmd *cmd, *tmp;
  	static LIST_HEAD(drop_cmd_list);
  
  	spin_lock_bh(&conn->cmd_lock);
  	list_for_each_entry_safe(cmd, tmp, &conn->conn_cmd_list, i_conn_node) {
  		if ((cmd->cmd_flags & ICF_NON_IMMEDIATE_UNSOLICITED_DATA) &&
  		    (cmd->write_data_done < conn->sess->sess_ops->FirstBurstLength) &&
  		    (cmd->write_data_done < cmd->se_cmd.data_length))
  			list_move_tail(&cmd->i_conn_node, &drop_cmd_list);
  	}
  	spin_unlock_bh(&conn->cmd_lock);
  
  	list_for_each_entry_safe(cmd, tmp, &drop_cmd_list, i_conn_node) {
  		list_del_init(&cmd->i_conn_node);
  		if (cmd->i_state != ISTATE_REMOVE) {
  			struct isert_cmd *isert_cmd = iscsit_priv_cmd(cmd);
  
  			isert_info("conn %p dropping cmd %p\n", conn, cmd);
  			isert_put_cmd(isert_cmd, true);
  		}
  	}
  }
  
  static void isert_wait_conn(struct iscsi_conn *conn)
  {
  	struct isert_conn *isert_conn = conn->context;
  
  	isert_info("Starting conn %p\n", isert_conn);
  
  	mutex_lock(&isert_conn->mutex);
  	isert_conn_terminate(isert_conn);
  	mutex_unlock(&isert_conn->mutex);
  
  	ib_drain_qp(isert_conn->qp);
  	isert_put_unsol_pending_cmds(conn);
  	isert_wait4cmds(conn);
  	isert_wait4logout(isert_conn);
  
  	queue_work(isert_release_wq, &isert_conn->release_work);
  }
  
  static void isert_free_conn(struct iscsi_conn *conn)
  {
  	struct isert_conn *isert_conn = conn->context;
  
  	ib_drain_qp(isert_conn->qp);
  	isert_put_conn(isert_conn);
  }
  
  static void isert_get_rx_pdu(struct iscsi_conn *conn)
  {
  	struct completion comp;
  
  	init_completion(&comp);
  
  	wait_for_completion_interruptible(&comp);
  }
  
  static struct iscsit_transport iser_target_transport = {
  	.name			= "IB/iSER",
  	.transport_type		= ISCSI_INFINIBAND,
  	.rdma_shutdown		= true,
  	.priv_size		= sizeof(struct isert_cmd),
  	.owner			= THIS_MODULE,
  	.iscsit_setup_np	= isert_setup_np,
  	.iscsit_accept_np	= isert_accept_np,
  	.iscsit_free_np		= isert_free_np,
  	.iscsit_wait_conn	= isert_wait_conn,
  	.iscsit_free_conn	= isert_free_conn,
  	.iscsit_get_login_rx	= isert_get_login_rx,
  	.iscsit_put_login_tx	= isert_put_login_tx,
  	.iscsit_immediate_queue	= isert_immediate_queue,
  	.iscsit_response_queue	= isert_response_queue,
  	.iscsit_get_dataout	= isert_get_dataout,
  	.iscsit_queue_data_in	= isert_put_datain,
  	.iscsit_queue_status	= isert_put_response,
  	.iscsit_aborted_task	= isert_aborted_task,
  	.iscsit_get_rx_pdu	= isert_get_rx_pdu,
  	.iscsit_get_sup_prot_ops = isert_get_sup_prot_ops,
  };
  
  static int __init isert_init(void)
  {
  	int ret;
  
  	isert_comp_wq = alloc_workqueue("isert_comp_wq",
  					WQ_UNBOUND | WQ_HIGHPRI, 0);
  	if (!isert_comp_wq) {
  		isert_err("Unable to allocate isert_comp_wq\n");
  		return -ENOMEM;
  	}
  
  	isert_release_wq = alloc_workqueue("isert_release_wq", WQ_UNBOUND,
  					WQ_UNBOUND_MAX_ACTIVE);
  	if (!isert_release_wq) {
  		isert_err("Unable to allocate isert_release_wq\n");
  		ret = -ENOMEM;
  		goto destroy_comp_wq;
  	}
  
  	iscsit_register_transport(&iser_target_transport);
  	isert_info("iSER_TARGET[0] - Loaded iser_target_transport\n");
  
  	return 0;
  
  destroy_comp_wq:
  	destroy_workqueue(isert_comp_wq);
  
  	return ret;
  }
  
  static void __exit isert_exit(void)
  {
  	flush_scheduled_work();
  	destroy_workqueue(isert_release_wq);
  	destroy_workqueue(isert_comp_wq);
  	iscsit_unregister_transport(&iser_target_transport);
  	isert_info("iSER_TARGET[0] - Released iser_target_transport\n");
  }
  
  MODULE_DESCRIPTION("iSER-Target for mainline target infrastructure");
  MODULE_AUTHOR("nab@Linux-iSCSI.org");
  MODULE_LICENSE("GPL");
  
  module_init(isert_init);
  module_exit(isert_exit);
  