1 files changed, 629 insertions, 249 deletions

diff --git a/drivers/infiniband/ulp/iser/iser_verbs.c b/drivers/infiniband/ulp/iser/iser_verbs.c
index 993f0a8ff28..ea01075f9f9 100644
--- a/drivers/infiniband/ulp/iser/iser_verbs.c
+++ b/drivers/infiniband/ulp/iser/iser_verbs.c
@@ -1,6 +1,7 @@
 /*
  * Copyright (c) 2004, 2005, 2006 Voltaire, Inc. All rights reserved.
  * Copyright (c) 2005, 2006 Cisco Systems.  All rights reserved.
+ * Copyright (c) 2013-2014 Mellanox Technologies. 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
@@ -29,20 +30,17 @@
  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
- *
- * $Id: iser_verbs.c 7051 2006-05-10 12:29:11Z ogerlitz $
  */
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/slab.h>
 #include <linux/delay.h>
-#include <linux/version.h>
 
 #include "iscsi_iser.h"
 
 #define ISCSI_ISER_MAX_CONN	8
-#define ISER_MAX_CQ_LEN		((ISER_QP_MAX_RECV_DTOS + \
-				ISER_QP_MAX_REQ_DTOS) *   \
-				 ISCSI_ISER_MAX_CONN)
+#define ISER_MAX_RX_CQ_LEN	(ISER_QP_MAX_RECV_DTOS * ISCSI_ISER_MAX_CONN)
+#define ISER_MAX_TX_CQ_LEN	(ISER_QP_MAX_REQ_DTOS  * ISCSI_ISER_MAX_CONN)
 
 static void iser_cq_tasklet_fn(unsigned long data);
 static void iser_cq_callback(struct ib_cq *cq, void *cq_context);
@@ -57,6 +55,13 @@ static void iser_qp_event_callback(struct ib_event *cause, void *context)
 	iser_err("got qp event %d\n",cause->event);
 }
 
+static void iser_event_handler(struct ib_event_handler *handler,
+				struct ib_event *event)
+{
+	iser_err("async event %d on device %s port %d\n", event->event,
+		event->device->name, event->element.port_num);
+}
+
 /**
  * iser_create_device_ib_res - creates Protection Domain (PD), Completion
  * Queue (CQ), DMA Memory Region (DMA MR) with the device associated with
@@ -66,24 +71,78 @@ static void iser_qp_event_callback(struct ib_event *cause, void *context)
  */
 static int iser_create_device_ib_res(struct iser_device *device)
 {
+	struct iser_cq_desc *cq_desc;
+	struct ib_device_attr *dev_attr = &device->dev_attr;
+	int ret, i, j;
+
+	ret = ib_query_device(device->ib_device, dev_attr);
+	if (ret) {
+		pr_warn("Query device failed for %s\n", device->ib_device->name);
+		return ret;
+	}
+
+	/* Assign function handles  - based on FMR support */
+	if (device->ib_device->alloc_fmr && device->ib_device->dealloc_fmr &&
+	    device->ib_device->map_phys_fmr && device->ib_device->unmap_fmr) {
+		iser_info("FMR supported, using FMR for registration\n");
+		device->iser_alloc_rdma_reg_res = iser_create_fmr_pool;
+		device->iser_free_rdma_reg_res = iser_free_fmr_pool;
+		device->iser_reg_rdma_mem = iser_reg_rdma_mem_fmr;
+		device->iser_unreg_rdma_mem = iser_unreg_mem_fmr;
+	} else
+	if (dev_attr->device_cap_flags & IB_DEVICE_MEM_MGT_EXTENSIONS) {
+		iser_info("FastReg supported, using FastReg for registration\n");
+		device->iser_alloc_rdma_reg_res = iser_create_fastreg_pool;
+		device->iser_free_rdma_reg_res = iser_free_fastreg_pool;
+		device->iser_reg_rdma_mem = iser_reg_rdma_mem_fastreg;
+		device->iser_unreg_rdma_mem = iser_unreg_mem_fastreg;
+	} else {
+		iser_err("IB device does not support FMRs nor FastRegs, can't register memory\n");
+		return -1;
+	}
+
+	device->cqs_used = min(ISER_MAX_CQ, device->ib_device->num_comp_vectors);
+	iser_info("using %d CQs, device %s supports %d vectors\n",
+		  device->cqs_used, device->ib_device->name,
+		  device->ib_device->num_comp_vectors);
+
+	device->cq_desc = kmalloc(sizeof(struct iser_cq_desc) * device->cqs_used,
+				  GFP_KERNEL);
+	if (device->cq_desc == NULL)
+		goto cq_desc_err;
+	cq_desc = device->cq_desc;
+
 	device->pd = ib_alloc_pd(device->ib_device);
 	if (IS_ERR(device->pd))
 		goto pd_err;
 
-	device->cq = ib_create_cq(device->ib_device,
-				  iser_cq_callback,
-				  iser_cq_event_callback,
-				  (void *)device,
-				  ISER_MAX_CQ_LEN, 0);
-	if (IS_ERR(device->cq))
-		goto cq_err;
+	for (i = 0; i < device->cqs_used; i++) {
+		cq_desc[i].device   = device;
+		cq_desc[i].cq_index = i;
+
+		device->rx_cq[i] = ib_create_cq(device->ib_device,
+					  iser_cq_callback,
+					  iser_cq_event_callback,
+					  (void *)&cq_desc[i],
+					  ISER_MAX_RX_CQ_LEN, i);
+		if (IS_ERR(device->rx_cq[i]))
+			goto cq_err;
+
+		device->tx_cq[i] = ib_create_cq(device->ib_device,
+					  NULL, iser_cq_event_callback,
+					  (void *)&cq_desc[i],
+					  ISER_MAX_TX_CQ_LEN, i);
 
-	if (ib_req_notify_cq(device->cq, IB_CQ_NEXT_COMP))
-		goto cq_arm_err;
+		if (IS_ERR(device->tx_cq[i]))
+			goto cq_err;
 
-	tasklet_init(&device->cq_tasklet,
-		     iser_cq_tasklet_fn,
-		     (unsigned long)device);
+		if (ib_req_notify_cq(device->rx_cq[i], IB_CQ_NEXT_COMP))
+			goto cq_err;
+
+		tasklet_init(&device->cq_tasklet[i],
+			     iser_cq_tasklet_fn,
+			(unsigned long)&cq_desc[i]);
+	}
 
 	device->mr = ib_get_dma_mr(device->pd, IB_ACCESS_LOCAL_WRITE |
 				   IB_ACCESS_REMOTE_WRITE |
@@ -91,15 +150,29 @@ static int iser_create_device_ib_res(struct iser_device *device)
 	if (IS_ERR(device->mr))
 		goto dma_mr_err;
 
+	INIT_IB_EVENT_HANDLER(&device->event_handler, device->ib_device,
+				iser_event_handler);
+	if (ib_register_event_handler(&device->event_handler))
+		goto handler_err;
+
 	return 0;
 
+handler_err:
+	ib_dereg_mr(device->mr);
 dma_mr_err:
-	tasklet_kill(&device->cq_tasklet);
-cq_arm_err:
-	ib_destroy_cq(device->cq);
+	for (j = 0; j < device->cqs_used; j++)
+		tasklet_kill(&device->cq_tasklet[j]);
 cq_err:
+	for (j = 0; j < i; j++) {
+		if (device->tx_cq[j])
+			ib_destroy_cq(device->tx_cq[j]);
+		if (device->rx_cq[j])
+			ib_destroy_cq(device->rx_cq[j]);
+	}
 	ib_dealloc_pd(device->pd);
 pd_err:
+	kfree(device->cq_desc);
+cq_desc_err:
 	iser_err("failed to allocate an IB resource\n");
 	return -1;
 }
@@ -110,43 +183,45 @@ pd_err:
  */
 static void iser_free_device_ib_res(struct iser_device *device)
 {
+	int i;
 	BUG_ON(device->mr == NULL);
 
-	tasklet_kill(&device->cq_tasklet);
+	for (i = 0; i < device->cqs_used; i++) {
+		tasklet_kill(&device->cq_tasklet[i]);
+		(void)ib_destroy_cq(device->tx_cq[i]);
+		(void)ib_destroy_cq(device->rx_cq[i]);
+		device->tx_cq[i] = NULL;
+		device->rx_cq[i] = NULL;
+	}
 
+	(void)ib_unregister_event_handler(&device->event_handler);
 	(void)ib_dereg_mr(device->mr);
-	(void)ib_destroy_cq(device->cq);
 	(void)ib_dealloc_pd(device->pd);
 
+	kfree(device->cq_desc);
+
 	device->mr = NULL;
-	device->cq = NULL;
 	device->pd = NULL;
 }
 
 /**
- * iser_create_ib_conn_res - Creates FMR pool and Queue-Pair (QP)
+ * iser_create_fmr_pool - Creates FMR pool and page_vector
  *
- * returns 0 on success, -1 on failure
+ * returns 0 on success, or errno code on failure
  */
-static int iser_create_ib_conn_res(struct iser_conn *ib_conn)
+int iser_create_fmr_pool(struct iser_conn *ib_conn, unsigned cmds_max)
 {
-	struct iser_device	*device;
-	struct ib_qp_init_attr	init_attr;
-	int			ret;
+	struct iser_device *device = ib_conn->device;
 	struct ib_fmr_pool_param params;
+	int ret = -ENOMEM;
 
-	BUG_ON(ib_conn->device == NULL);
-
-	device = ib_conn->device;
+	ib_conn->fmr.page_vec = kmalloc(sizeof(*ib_conn->fmr.page_vec) +
+					(sizeof(u64)*(ISCSI_ISER_SG_TABLESIZE + 1)),
+					GFP_KERNEL);
+	if (!ib_conn->fmr.page_vec)
+		return ret;
 
-	ib_conn->page_vec = kmalloc(sizeof(struct iser_page_vec) +
-				    (sizeof(u64) * (ISCSI_ISER_SG_TABLESIZE +1)),
-				    GFP_KERNEL);
-	if (!ib_conn->page_vec) {
-		ret = -ENOMEM;
-		goto alloc_err;
-	}
-	ib_conn->page_vec->pages = (u64 *) (ib_conn->page_vec + 1);
+	ib_conn->fmr.page_vec->pages = (u64 *)(ib_conn->fmr.page_vec + 1);
 
 	params.page_shift        = SHIFT_4K;
 	/* when the first/last SG element are not start/end *
@@ -154,78 +229,290 @@ static int iser_create_ib_conn_res(struct iser_conn *ib_conn)
 	params.max_pages_per_fmr = ISCSI_ISER_SG_TABLESIZE + 1;
 	/* make the pool size twice the max number of SCSI commands *
 	 * the ML is expected to queue, watermark for unmap at 50%  */
-	params.pool_size	 = ISCSI_DEF_XMIT_CMDS_MAX * 2;
-	params.dirty_watermark	 = ISCSI_DEF_XMIT_CMDS_MAX;
+	params.pool_size	 = cmds_max * 2;
+	params.dirty_watermark	 = cmds_max;
 	params.cache		 = 0;
 	params.flush_function	 = NULL;
 	params.access		 = (IB_ACCESS_LOCAL_WRITE  |
 				    IB_ACCESS_REMOTE_WRITE |
 				    IB_ACCESS_REMOTE_READ);
 
-	ib_conn->fmr_pool = ib_create_fmr_pool(device->pd, &params);
-	if (IS_ERR(ib_conn->fmr_pool)) {
-		ret = PTR_ERR(ib_conn->fmr_pool);
-		goto fmr_pool_err;
+	ib_conn->fmr.pool = ib_create_fmr_pool(device->pd, &params);
+	if (!IS_ERR(ib_conn->fmr.pool))
+		return 0;
+
+	/* no FMR => no need for page_vec */
+	kfree(ib_conn->fmr.page_vec);
+	ib_conn->fmr.page_vec = NULL;
+
+	ret = PTR_ERR(ib_conn->fmr.pool);
+	ib_conn->fmr.pool = NULL;
+	if (ret != -ENOSYS) {
+		iser_err("FMR allocation failed, err %d\n", ret);
+		return ret;
+	} else {
+		iser_warn("FMRs are not supported, using unaligned mode\n");
+		return 0;
 	}
+}
+
+/**
+ * iser_free_fmr_pool - releases the FMR pool and page vec
+ */
+void iser_free_fmr_pool(struct iser_conn *ib_conn)
+{
+	iser_info("freeing conn %p fmr pool %p\n",
+		  ib_conn, ib_conn->fmr.pool);
+
+	if (ib_conn->fmr.pool != NULL)
+		ib_destroy_fmr_pool(ib_conn->fmr.pool);
+
+	ib_conn->fmr.pool = NULL;
+
+	kfree(ib_conn->fmr.page_vec);
+	ib_conn->fmr.page_vec = NULL;
+}
+
+static int
+iser_create_fastreg_desc(struct ib_device *ib_device, struct ib_pd *pd,
+			 bool pi_enable, struct fast_reg_descriptor *desc)
+{
+	int ret;
+
+	desc->data_frpl = ib_alloc_fast_reg_page_list(ib_device,
+						      ISCSI_ISER_SG_TABLESIZE + 1);
+	if (IS_ERR(desc->data_frpl)) {
+		ret = PTR_ERR(desc->data_frpl);
+		iser_err("Failed to allocate ib_fast_reg_page_list err=%d\n",
+			 ret);
+		return PTR_ERR(desc->data_frpl);
+	}
+
+	desc->data_mr = ib_alloc_fast_reg_mr(pd, ISCSI_ISER_SG_TABLESIZE + 1);
+	if (IS_ERR(desc->data_mr)) {
+		ret = PTR_ERR(desc->data_mr);
+		iser_err("Failed to allocate ib_fast_reg_mr err=%d\n", ret);
+		goto fast_reg_mr_failure;
+	}
+	desc->reg_indicators |= ISER_DATA_KEY_VALID;
+
+	if (pi_enable) {
+		struct ib_mr_init_attr mr_init_attr = {0};
+		struct iser_pi_context *pi_ctx = NULL;
+
+		desc->pi_ctx = kzalloc(sizeof(*desc->pi_ctx), GFP_KERNEL);
+		if (!desc->pi_ctx) {
+			iser_err("Failed to allocate pi context\n");
+			ret = -ENOMEM;
+			goto pi_ctx_alloc_failure;
+		}
+		pi_ctx = desc->pi_ctx;
+
+		pi_ctx->prot_frpl = ib_alloc_fast_reg_page_list(ib_device,
+						    ISCSI_ISER_SG_TABLESIZE);
+		if (IS_ERR(pi_ctx->prot_frpl)) {
+			ret = PTR_ERR(pi_ctx->prot_frpl);
+			iser_err("Failed to allocate prot frpl ret=%d\n",
+				 ret);
+			goto prot_frpl_failure;
+		}
+
+		pi_ctx->prot_mr = ib_alloc_fast_reg_mr(pd,
+						ISCSI_ISER_SG_TABLESIZE + 1);
+		if (IS_ERR(pi_ctx->prot_mr)) {
+			ret = PTR_ERR(pi_ctx->prot_mr);
+			iser_err("Failed to allocate prot frmr ret=%d\n",
+				 ret);
+			goto prot_mr_failure;
+		}
+		desc->reg_indicators |= ISER_PROT_KEY_VALID;
+
+		mr_init_attr.max_reg_descriptors = 2;
+		mr_init_attr.flags |= IB_MR_SIGNATURE_EN;
+		pi_ctx->sig_mr = ib_create_mr(pd, &mr_init_attr);
+		if (IS_ERR(pi_ctx->sig_mr)) {
+			ret = PTR_ERR(pi_ctx->sig_mr);
+			iser_err("Failed to allocate signature enabled mr err=%d\n",
+				 ret);
+			goto sig_mr_failure;
+		}
+		desc->reg_indicators |= ISER_SIG_KEY_VALID;
+	}
+	desc->reg_indicators &= ~ISER_FASTREG_PROTECTED;
+
+	iser_dbg("Create fr_desc %p page_list %p\n",
+		 desc, desc->data_frpl->page_list);
+
+	return 0;
+sig_mr_failure:
+	ib_dereg_mr(desc->pi_ctx->prot_mr);
+prot_mr_failure:
+	ib_free_fast_reg_page_list(desc->pi_ctx->prot_frpl);
+prot_frpl_failure:
+	kfree(desc->pi_ctx);
+pi_ctx_alloc_failure:
+	ib_dereg_mr(desc->data_mr);
+fast_reg_mr_failure:
+	ib_free_fast_reg_page_list(desc->data_frpl);
+
+	return ret;
+}
+
+/**
+ * iser_create_fastreg_pool - Creates pool of fast_reg descriptors
+ * for fast registration work requests.
+ * returns 0 on success, or errno code on failure
+ */
+int iser_create_fastreg_pool(struct iser_conn *ib_conn, unsigned cmds_max)
+{
+	struct iser_device	*device = ib_conn->device;
+	struct fast_reg_descriptor	*desc;
+	int i, ret;
+
+	INIT_LIST_HEAD(&ib_conn->fastreg.pool);
+	ib_conn->fastreg.pool_size = 0;
+	for (i = 0; i < cmds_max; i++) {
+		desc = kzalloc(sizeof(*desc), GFP_KERNEL);
+		if (!desc) {
+			iser_err("Failed to allocate a new fast_reg descriptor\n");
+			ret = -ENOMEM;
+			goto err;
+		}
+
+		ret = iser_create_fastreg_desc(device->ib_device, device->pd,
+					       ib_conn->pi_support, desc);
+		if (ret) {
+			iser_err("Failed to create fastreg descriptor err=%d\n",
+				 ret);
+			kfree(desc);
+			goto err;
+		}
+
+		list_add_tail(&desc->list, &ib_conn->fastreg.pool);
+		ib_conn->fastreg.pool_size++;
+	}
+
+	return 0;
+
+err:
+	iser_free_fastreg_pool(ib_conn);
+	return ret;
+}
+
+/**
+ * iser_free_fastreg_pool - releases the pool of fast_reg descriptors
+ */
+void iser_free_fastreg_pool(struct iser_conn *ib_conn)
+{
+	struct fast_reg_descriptor *desc, *tmp;
+	int i = 0;
+
+	if (list_empty(&ib_conn->fastreg.pool))
+		return;
+
+	iser_info("freeing conn %p fr pool\n", ib_conn);
+
+	list_for_each_entry_safe(desc, tmp, &ib_conn->fastreg.pool, list) {
+		list_del(&desc->list);
+		ib_free_fast_reg_page_list(desc->data_frpl);
+		ib_dereg_mr(desc->data_mr);
+		if (desc->pi_ctx) {
+			ib_free_fast_reg_page_list(desc->pi_ctx->prot_frpl);
+			ib_dereg_mr(desc->pi_ctx->prot_mr);
+			ib_destroy_mr(desc->pi_ctx->sig_mr);
+			kfree(desc->pi_ctx);
+		}
+		kfree(desc);
+		++i;
+	}
+
+	if (i < ib_conn->fastreg.pool_size)
+		iser_warn("pool still has %d regions registered\n",
+			  ib_conn->fastreg.pool_size - i);
+}
+
+/**
+ * iser_create_ib_conn_res - Queue-Pair (QP)
+ *
+ * returns 0 on success, -1 on failure
+ */
+static int iser_create_ib_conn_res(struct iser_conn *ib_conn)
+{
+	struct iser_device	*device;
+	struct ib_qp_init_attr	init_attr;
+	int			ret = -ENOMEM;
+	int index, min_index = 0;
+
+	BUG_ON(ib_conn->device == NULL);
+
+	device = ib_conn->device;
 
 	memset(&init_attr, 0, sizeof init_attr);
 
+	mutex_lock(&ig.connlist_mutex);
+	/* select the CQ with the minimal number of usages */
+	for (index = 0; index < device->cqs_used; index++)
+		if (device->cq_active_qps[index] <
+		    device->cq_active_qps[min_index])
+			min_index = index;
+	device->cq_active_qps[min_index]++;
+	mutex_unlock(&ig.connlist_mutex);
+	iser_info("cq index %d used for ib_conn %p\n", min_index, ib_conn);
+
 	init_attr.event_handler = iser_qp_event_callback;
 	init_attr.qp_context	= (void *)ib_conn;
-	init_attr.send_cq	= device->cq;
-	init_attr.recv_cq	= device->cq;
-	init_attr.cap.max_send_wr  = ISER_QP_MAX_REQ_DTOS;
+	init_attr.send_cq	= device->tx_cq[min_index];
+	init_attr.recv_cq	= device->rx_cq[min_index];
 	init_attr.cap.max_recv_wr  = ISER_QP_MAX_RECV_DTOS;
-	init_attr.cap.max_send_sge = MAX_REGD_BUF_VECTOR_LEN;
-	init_attr.cap.max_recv_sge = 2;
+	init_attr.cap.max_send_sge = 2;
+	init_attr.cap.max_recv_sge = 1;
 	init_attr.sq_sig_type	= IB_SIGNAL_REQ_WR;
 	init_attr.qp_type	= IB_QPT_RC;
+	if (ib_conn->pi_support) {
+		init_attr.cap.max_send_wr = ISER_QP_SIG_MAX_REQ_DTOS;
+		init_attr.create_flags |= IB_QP_CREATE_SIGNATURE_EN;
+	} else {
+		init_attr.cap.max_send_wr  = ISER_QP_MAX_REQ_DTOS;
+	}
 
 	ret = rdma_create_qp(ib_conn->cma_id, device->pd, &init_attr);
 	if (ret)
-		goto qp_err;
+		goto out_err;
 
 	ib_conn->qp = ib_conn->cma_id->qp;
-	iser_err("setting conn %p cma_id %p: fmr_pool %p qp %p\n",
-		 ib_conn, ib_conn->cma_id,
-		 ib_conn->fmr_pool, ib_conn->cma_id->qp);
+	iser_info("setting conn %p cma_id %p qp %p\n",
+		  ib_conn, ib_conn->cma_id,
+		  ib_conn->cma_id->qp);
 	return ret;
 
-qp_err:
-	(void)ib_destroy_fmr_pool(ib_conn->fmr_pool);
-fmr_pool_err:
-	kfree(ib_conn->page_vec);
-alloc_err:
+out_err:
 	iser_err("unable to alloc mem or create resource, err %d\n", ret);
 	return ret;
 }
 
 /**
- * releases the FMR pool, QP and CMA ID objects, returns 0 on success,
+ * releases the QP objects, returns 0 on success,
  * -1 on failure
  */
 static int iser_free_ib_conn_res(struct iser_conn *ib_conn)
 {
+	int cq_index;
 	BUG_ON(ib_conn == NULL);
 
-	iser_err("freeing conn %p cma_id %p fmr pool %p qp %p\n",
-		 ib_conn, ib_conn->cma_id,
-		 ib_conn->fmr_pool, ib_conn->qp);
+	iser_info("freeing conn %p cma_id %p qp %p\n",
+		  ib_conn, ib_conn->cma_id,
+		  ib_conn->qp);
 
 	/* qp is created only once both addr & route are resolved */
-	if (ib_conn->fmr_pool != NULL)
-		ib_destroy_fmr_pool(ib_conn->fmr_pool);
 
-	if (ib_conn->qp != NULL)
-		rdma_destroy_qp(ib_conn->cma_id);
+	if (ib_conn->qp != NULL) {
+		cq_index = ((struct iser_cq_desc *)ib_conn->qp->recv_cq->cq_context)->cq_index;
+		ib_conn->device->cq_active_qps[cq_index]--;
 
-	if (ib_conn->cma_id != NULL)
-		rdma_destroy_id(ib_conn->cma_id);
+		rdma_destroy_qp(ib_conn->cma_id);
+	}
 
-	ib_conn->fmr_pool = NULL;
 	ib_conn->qp	  = NULL;
-	ib_conn->cma_id   = NULL;
-	kfree(ib_conn->page_vec);
 
 	return 0;
 }
@@ -272,7 +559,7 @@ static void iser_device_try_release(struct iser_device *device)
 {
 	mutex_lock(&ig.device_list_mutex);
 	device->refcount--;
-	iser_err("device %p refcount %d\n",device,device->refcount);
+	iser_info("device %p refcount %d\n", device, device->refcount);
 	if (!device->refcount) {
 		iser_free_device_ib_res(device);
 		list_del(&device->ig_list);
@@ -281,17 +568,6 @@ static void iser_device_try_release(struct iser_device *device)
 	mutex_unlock(&ig.device_list_mutex);
 }
 
-int iser_conn_state_comp(struct iser_conn *ib_conn,
-			enum iser_ib_conn_state comp)
-{
-	int ret;
-
-	spin_lock_bh(&ib_conn->lock);
-	ret = (ib_conn->state == comp);
-	spin_unlock_bh(&ib_conn->lock);
-	return ret;
-}
-
 static int iser_conn_state_comp_exch(struct iser_conn *ib_conn,
 				     enum iser_ib_conn_state comp,
 				     enum iser_ib_conn_state exch)
@@ -305,27 +581,46 @@ static int iser_conn_state_comp_exch(struct iser_conn *ib_conn,
 	return ret;
 }
 
+void iser_release_work(struct work_struct *work)
+{
+	struct iser_conn *ib_conn;
+
+	ib_conn = container_of(work, struct iser_conn, release_work);
+
+	/* wait for .conn_stop callback */
+	wait_for_completion(&ib_conn->stop_completion);
+
+	/* wait for the qp`s post send and post receive buffers to empty */
+	wait_event_interruptible(ib_conn->wait,
+				 ib_conn->state == ISER_CONN_DOWN);
+
+	iser_conn_release(ib_conn);
+}
+
 /**
  * Frees all conn objects and deallocs conn descriptor
  */
-static void iser_conn_release(struct iser_conn *ib_conn)
+void iser_conn_release(struct iser_conn *ib_conn)
 {
 	struct iser_device  *device = ib_conn->device;
 
-	BUG_ON(ib_conn->state != ISER_CONN_DOWN);
+	BUG_ON(ib_conn->state == ISER_CONN_UP);
 
 	mutex_lock(&ig.connlist_mutex);
 	list_del(&ib_conn->conn_list);
 	mutex_unlock(&ig.connlist_mutex);
-
+	iser_free_rx_descriptors(ib_conn);
 	iser_free_ib_conn_res(ib_conn);
 	ib_conn->device = NULL;
 	/* on EVENT_ADDR_ERROR there's no device yet for this conn */
 	if (device != NULL)
 		iser_device_try_release(device);
-	if (ib_conn->iser_conn)
-		ib_conn->iser_conn->ib_conn = NULL;
-	kfree(ib_conn);
+	/* if cma handler context, the caller actually destroy the id */
+	if (ib_conn->cma_id != NULL) {
+		rdma_destroy_id(ib_conn->cma_id);
+		ib_conn->cma_id = NULL;
+	}
+	iscsi_destroy_endpoint(ib_conn->ep);
 }
 
 /**
@@ -345,16 +640,12 @@ void iser_conn_terminate(struct iser_conn *ib_conn)
 	if (err)
 		iser_err("Failed to disconnect, conn: 0x%p err %d\n",
 			 ib_conn,err);
-
-	wait_event_interruptible(ib_conn->wait,
-				 ib_conn->state == ISER_CONN_DOWN);
-
-	iser_conn_release(ib_conn);
 }
 
 static void iser_connect_error(struct rdma_cm_id *cma_id)
 {
 	struct iser_conn *ib_conn;
+
 	ib_conn = (struct iser_conn *)cma_id->context;
 
 	ib_conn->state = ISER_CONN_DOWN;
@@ -377,10 +668,24 @@ static void iser_addr_handler(struct rdma_cm_id *cma_id)
 	ib_conn = (struct iser_conn *)cma_id->context;
 	ib_conn->device = device;
 
+	/* connection T10-PI support */
+	if (iser_pi_enable) {
+		if (!(device->dev_attr.device_cap_flags &
+		      IB_DEVICE_SIGNATURE_HANDOVER)) {
+			iser_warn("T10-PI requested but not supported on %s, "
+				  "continue without T10-PI\n",
+				  ib_conn->device->ib_device->name);
+			ib_conn->pi_support = false;
+		} else {
+			ib_conn->pi_support = true;
+		}
+	}
+
 	ret = rdma_resolve_route(cma_id, 1000);
 	if (ret) {
 		iser_err("resolve route failed: %d\n", ret);
 		iser_connect_error(cma_id);
+		return;
 	}
 }
 
@@ -388,24 +693,24 @@ static void iser_route_handler(struct rdma_cm_id *cma_id)
 {
 	struct rdma_conn_param conn_param;
 	int    ret;
+	struct iser_cm_hdr req_hdr;
 
 	ret = iser_create_ib_conn_res((struct iser_conn *)cma_id->context);
 	if (ret)
 		goto failure;
 
-	iser_dbg("path.mtu is %d setting it to %d\n",
-		 cma_id->route.path_rec->mtu, IB_MTU_1024);
-
-	/* we must set the MTU to 1024 as this is what the target is assuming */
-	if (cma_id->route.path_rec->mtu > IB_MTU_1024)
-		cma_id->route.path_rec->mtu = IB_MTU_1024;
-
 	memset(&conn_param, 0, sizeof conn_param);
 	conn_param.responder_resources = 4;
 	conn_param.initiator_depth     = 1;
 	conn_param.retry_count	       = 7;
 	conn_param.rnr_retry_count     = 6;
 
+	memset(&req_hdr, 0, sizeof(req_hdr));
+	req_hdr.flags = (ISER_ZBVA_NOT_SUPPORTED |
+			ISER_SEND_W_INV_NOT_SUPPORTED);
+	conn_param.private_data		= (void *)&req_hdr;
+	conn_param.private_data_len	= sizeof(struct iser_cm_hdr);
+
 	ret = rdma_connect(cma_id, &conn_param);
 	if (ret) {
 		iser_err("failure connecting: %d\n", ret);
@@ -420,10 +725,15 @@ failure:
 static void iser_connected_handler(struct rdma_cm_id *cma_id)
 {
 	struct iser_conn *ib_conn;
+	struct ib_qp_attr attr;
+	struct ib_qp_init_attr init_attr;
+
+	(void)ib_query_qp(cma_id->qp, &attr, ~0, &init_attr);
+	iser_info("remote qpn:%x my qpn:%x\n", attr.dest_qp_num, cma_id->qp->qp_num);
 
 	ib_conn = (struct iser_conn *)cma_id->context;
-	ib_conn->state = ISER_CONN_UP;
-	wake_up_interruptible(&ib_conn->wait);
+	if (iser_conn_state_comp_exch(ib_conn, ISER_CONN_PENDING, ISER_CONN_UP))
+		wake_up_interruptible(&ib_conn->wait);
 }
 
 static void iser_disconnected_handler(struct rdma_cm_id *cma_id)
@@ -431,17 +741,19 @@ static void iser_disconnected_handler(struct rdma_cm_id *cma_id)
 	struct iser_conn *ib_conn;
 
 	ib_conn = (struct iser_conn *)cma_id->context;
-	ib_conn->disc_evt_flag = 1;
 
 	/* getting here when the state is UP means that the conn is being *
 	 * terminated asynchronously from the iSCSI layer's perspective.  */
 	if (iser_conn_state_comp_exch(ib_conn, ISER_CONN_UP,
-				      ISER_CONN_TERMINATING))
-		iscsi_conn_failure(ib_conn->iser_conn->iscsi_conn,
-				   ISCSI_ERR_CONN_FAILED);
+					ISER_CONN_TERMINATING)){
+		if (ib_conn->iscsi_conn)
+			iscsi_conn_failure(ib_conn->iscsi_conn, ISCSI_ERR_CONN_FAILED);
+		else
+			iser_err("iscsi_iser connection isn't bound\n");
+	}
 
 	/* Complete the termination process if no posts are pending */
-	if ((atomic_read(&ib_conn->post_recv_buf_count) == 0) &&
+	if (ib_conn->post_recv_buf_count == 0 &&
 	    (atomic_read(&ib_conn->post_send_buf_count) == 0)) {
 		ib_conn->state = ISER_CONN_DOWN;
 		wake_up_interruptible(&ib_conn->wait);
@@ -450,9 +762,8 @@ static void iser_disconnected_handler(struct rdma_cm_id *cma_id)
 
 static int iser_cma_handler(struct rdma_cm_id *cma_id, struct rdma_cm_event *event)
 {
-	int ret = 0;
-
-	iser_err("event %d conn %p id %p\n",event->event,cma_id->context,cma_id);
+	iser_info("event %d status %d conn %p id %p\n",
+		  event->event, event->status, cma_id->context, cma_id);
 
 	switch (event->event) {
 	case RDMA_CM_EVENT_ADDR_RESOLVED:
@@ -469,46 +780,34 @@ static int iser_cma_handler(struct rdma_cm_id *cma_id, struct rdma_cm_event *eve
 	case RDMA_CM_EVENT_CONNECT_ERROR:
 	case RDMA_CM_EVENT_UNREACHABLE:
 	case RDMA_CM_EVENT_REJECTED:
-		iser_err("event: %d, error: %d\n", event->event, event->status);
 		iser_connect_error(cma_id);
 		break;
 	case RDMA_CM_EVENT_DISCONNECTED:
-		iser_disconnected_handler(cma_id);
-		break;
 	case RDMA_CM_EVENT_DEVICE_REMOVAL:
-		iser_err("Device removal is currently unsupported\n");
-		BUG();
+	case RDMA_CM_EVENT_ADDR_CHANGE:
+		iser_disconnected_handler(cma_id);
 		break;
 	default:
 		iser_err("Unexpected RDMA CM event (%d)\n", event->event);
 		break;
 	}
-	return ret;
+	return 0;
 }
 
-int iser_conn_init(struct iser_conn **ibconn)
+void iser_conn_init(struct iser_conn *ib_conn)
 {
-	struct iser_conn *ib_conn;
-
-	ib_conn = kzalloc(sizeof *ib_conn, GFP_KERNEL);
-	if (!ib_conn) {
-		iser_err("can't alloc memory for struct iser_conn\n");
-		return -ENOMEM;
-	}
 	ib_conn->state = ISER_CONN_INIT;
 	init_waitqueue_head(&ib_conn->wait);
-	atomic_set(&ib_conn->post_recv_buf_count, 0);
+	ib_conn->post_recv_buf_count = 0;
 	atomic_set(&ib_conn->post_send_buf_count, 0);
+	init_completion(&ib_conn->stop_completion);
 	INIT_LIST_HEAD(&ib_conn->conn_list);
 	spin_lock_init(&ib_conn->lock);
-
-	*ibconn = ib_conn;
-	return 0;
 }
 
  /**
  * starts the process of connecting to the target
- * sleeps untill the connection is established or rejected
+ * sleeps until the connection is established or rejected
  */
 int iser_connect(struct iser_conn   *ib_conn,
 		 struct sockaddr_in *src_addr,
@@ -518,20 +817,20 @@ int iser_connect(struct iser_conn   *ib_conn,
 	struct sockaddr *src, *dst;
 	int err = 0;
 
-	sprintf(ib_conn->name,"%d.%d.%d.%d:%d",
-		NIPQUAD(dst_addr->sin_addr.s_addr), dst_addr->sin_port);
+	sprintf(ib_conn->name, "%pI4:%d",
+		&dst_addr->sin_addr.s_addr, dst_addr->sin_port);
 
 	/* the device is known only --after-- address resolution */
 	ib_conn->device = NULL;
 
-	iser_err("connecting to: %d.%d.%d.%d, port 0x%x\n",
-		 NIPQUAD(dst_addr->sin_addr), dst_addr->sin_port);
+	iser_info("connecting to: %pI4, port 0x%x\n",
+		  &dst_addr->sin_addr, dst_addr->sin_port);
 
 	ib_conn->state = ISER_CONN_PENDING;
 
 	ib_conn->cma_id = rdma_create_id(iser_cma_handler,
 					     (void *)ib_conn,
-					     RDMA_PS_TCP);
+					     RDMA_PS_TCP, IB_QPT_RC);
 	if (IS_ERR(ib_conn->cma_id)) {
 		err = PTR_ERR(ib_conn->cma_id);
 		iser_err("rdma_create_id failed: %d\n", err);
@@ -587,7 +886,7 @@ int iser_reg_page_vec(struct iser_conn     *ib_conn,
 	page_list = page_vec->pages;
 	io_addr	  = page_list[0];
 
-	mem  = ib_fmr_pool_map_phys(ib_conn->fmr_pool,
+	mem  = ib_fmr_pool_map_phys(ib_conn->fmr.pool,
 				    page_list,
 				    page_vec->length,
 				    io_addr);
@@ -602,7 +901,7 @@ int iser_reg_page_vec(struct iser_conn     *ib_conn,
 	mem_reg->rkey  = mem->fmr->rkey;
 	mem_reg->len   = page_vec->length * SIZE_4K;
 	mem_reg->va    = io_addr;
-	mem_reg->is_fmr = 1;
+	mem_reg->is_mr = 1;
 	mem_reg->mem_h = (void *)mem;
 
 	mem_reg->va   += page_vec->offset;
@@ -620,12 +919,18 @@ int iser_reg_page_vec(struct iser_conn     *ib_conn,
 }
 
 /**
- * Unregister (previosuly registered) memory.
+ * Unregister (previosuly registered using FMR) memory.
+ * If memory is non-FMR does nothing.
  */
-void iser_unreg_mem(struct iser_mem_reg *reg)
+void iser_unreg_mem_fmr(struct iscsi_iser_task *iser_task,
+			enum iser_data_dir cmd_dir)
 {
+	struct iser_mem_reg *reg = &iser_task->rdma_regd[cmd_dir].reg;
 	int ret;
 
+	if (!reg->is_mr)
+		return;
+
 	iser_dbg("PHYSICAL Mem.Unregister mem_h %p\n",reg->mem_h);
 
 	ret = ib_fmr_pool_unmap((struct ib_pool_fmr *)reg->mem_h);
@@ -635,185 +940,260 @@ void iser_unreg_mem(struct iser_mem_reg *reg)
 	reg->mem_h = NULL;
 }
 
-/**
- * iser_dto_to_iov - builds IOV from a dto descriptor
- */
-static void iser_dto_to_iov(struct iser_dto *dto, struct ib_sge *iov, int iov_len)
+void iser_unreg_mem_fastreg(struct iscsi_iser_task *iser_task,
+			    enum iser_data_dir cmd_dir)
 {
-	int		     i;
-	struct ib_sge	     *sge;
-	struct iser_regd_buf *regd_buf;
+	struct iser_mem_reg *reg = &iser_task->rdma_regd[cmd_dir].reg;
+	struct iser_conn *ib_conn = iser_task->ib_conn;
+	struct fast_reg_descriptor *desc = reg->mem_h;
 
-	if (dto->regd_vector_len > iov_len) {
-		iser_err("iov size %d too small for posting dto of len %d\n",
-			 iov_len, dto->regd_vector_len);
-		BUG();
-	}
+	if (!reg->is_mr)
+		return;
 
-	for (i = 0; i < dto->regd_vector_len; i++) {
-		sge	    = &iov[i];
-		regd_buf  = dto->regd[i];
+	reg->mem_h = NULL;
+	reg->is_mr = 0;
+	spin_lock_bh(&ib_conn->lock);
+	list_add_tail(&desc->list, &ib_conn->fastreg.pool);
+	spin_unlock_bh(&ib_conn->lock);
+}
 
-		sge->addr   = regd_buf->reg.va;
-		sge->length = regd_buf->reg.len;
-		sge->lkey   = regd_buf->reg.lkey;
+int iser_post_recvl(struct iser_conn *ib_conn)
+{
+	struct ib_recv_wr rx_wr, *rx_wr_failed;
+	struct ib_sge	  sge;
+	int ib_ret;
 
-		if (dto->used_sz[i] > 0)  /* Adjust size */
-			sge->length = dto->used_sz[i];
+	sge.addr   = ib_conn->login_resp_dma;
+	sge.length = ISER_RX_LOGIN_SIZE;
+	sge.lkey   = ib_conn->device->mr->lkey;
 
-		/* offset and length should not exceed the regd buf length */
-		if (sge->length + dto->offset[i] > regd_buf->reg.len) {
-			iser_err("Used len:%ld + offset:%d, exceed reg.buf.len:"
-				 "%ld in dto:0x%p [%d], va:0x%08lX\n",
-				 (unsigned long)sge->length, dto->offset[i],
-				 (unsigned long)regd_buf->reg.len, dto, i,
-				 (unsigned long)sge->addr);
-			BUG();
-		}
+	rx_wr.wr_id   = (unsigned long)ib_conn->login_resp_buf;
+	rx_wr.sg_list = &sge;
+	rx_wr.num_sge = 1;
+	rx_wr.next    = NULL;
 
-		sge->addr += dto->offset[i]; /* Adjust offset */
+	ib_conn->post_recv_buf_count++;
+	ib_ret	= ib_post_recv(ib_conn->qp, &rx_wr, &rx_wr_failed);
+	if (ib_ret) {
+		iser_err("ib_post_recv failed ret=%d\n", ib_ret);
+		ib_conn->post_recv_buf_count--;
 	}
+	return ib_ret;
 }
 
-/**
- * iser_post_recv - Posts a receive buffer.
- *
- * returns 0 on success, -1 on failure
- */
-int iser_post_recv(struct iser_desc *rx_desc)
+int iser_post_recvm(struct iser_conn *ib_conn, int count)
 {
-	int		  ib_ret, ret_val = 0;
-	struct ib_recv_wr recv_wr, *recv_wr_failed;
-	struct ib_sge	  iov[2];
-	struct iser_conn  *ib_conn;
-	struct iser_dto   *recv_dto = &rx_desc->dto;
-
-	/* Retrieve conn */
-	ib_conn = recv_dto->ib_conn;
-
-	iser_dto_to_iov(recv_dto, iov, 2);
+	struct ib_recv_wr *rx_wr, *rx_wr_failed;
+	int i, ib_ret;
+	unsigned int my_rx_head = ib_conn->rx_desc_head;
+	struct iser_rx_desc *rx_desc;
+
+	for (rx_wr = ib_conn->rx_wr, i = 0; i < count; i++, rx_wr++) {
+		rx_desc		= &ib_conn->rx_descs[my_rx_head];
+		rx_wr->wr_id	= (unsigned long)rx_desc;
+		rx_wr->sg_list	= &rx_desc->rx_sg;
+		rx_wr->num_sge	= 1;
+		rx_wr->next	= rx_wr + 1;
+		my_rx_head = (my_rx_head + 1) & ib_conn->qp_max_recv_dtos_mask;
+	}
 
-	recv_wr.next	= NULL;
-	recv_wr.sg_list = iov;
-	recv_wr.num_sge = recv_dto->regd_vector_len;
-	recv_wr.wr_id	= (unsigned long)rx_desc;
+	rx_wr--;
+	rx_wr->next = NULL; /* mark end of work requests list */
 
-	atomic_inc(&ib_conn->post_recv_buf_count);
-	ib_ret	= ib_post_recv(ib_conn->qp, &recv_wr, &recv_wr_failed);
+	ib_conn->post_recv_buf_count += count;
+	ib_ret	= ib_post_recv(ib_conn->qp, ib_conn->rx_wr, &rx_wr_failed);
 	if (ib_ret) {
 		iser_err("ib_post_recv failed ret=%d\n", ib_ret);
-		atomic_dec(&ib_conn->post_recv_buf_count);
-		ret_val = -1;
-	}
-
-	return ret_val;
+		ib_conn->post_recv_buf_count -= count;
+	} else
+		ib_conn->rx_desc_head = my_rx_head;
+	return ib_ret;
 }
 
+
 /**
  * iser_start_send - Initiate a Send DTO operation
  *
  * returns 0 on success, -1 on failure
  */
-int iser_post_send(struct iser_desc *tx_desc)
+int iser_post_send(struct iser_conn *ib_conn, struct iser_tx_desc *tx_desc)
 {
-	int		  ib_ret, ret_val = 0;
+	int		  ib_ret;
 	struct ib_send_wr send_wr, *send_wr_failed;
-	struct ib_sge	  iov[MAX_REGD_BUF_VECTOR_LEN];
-	struct iser_conn  *ib_conn;
-	struct iser_dto   *dto = &tx_desc->dto;
-
-	ib_conn = dto->ib_conn;
 
-	iser_dto_to_iov(dto, iov, MAX_REGD_BUF_VECTOR_LEN);
+	ib_dma_sync_single_for_device(ib_conn->device->ib_device,
+		tx_desc->dma_addr, ISER_HEADERS_LEN, DMA_TO_DEVICE);
 
 	send_wr.next	   = NULL;
 	send_wr.wr_id	   = (unsigned long)tx_desc;
-	send_wr.sg_list	   = iov;
-	send_wr.num_sge	   = dto->regd_vector_len;
+	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 = dto->notify_enable ? IB_SEND_SIGNALED : 0;
+	send_wr.send_flags = IB_SEND_SIGNALED;
 
 	atomic_inc(&ib_conn->post_send_buf_count);
 
 	ib_ret = ib_post_send(ib_conn->qp, &send_wr, &send_wr_failed);
 	if (ib_ret) {
-		iser_err("Failed to start SEND DTO, dto: 0x%p, IOV len: %d\n",
-			 dto, dto->regd_vector_len);
 		iser_err("ib_post_send failed, ret:%d\n", ib_ret);
 		atomic_dec(&ib_conn->post_send_buf_count);
-		ret_val = -1;
 	}
-
-	return ret_val;
+	return ib_ret;
 }
 
-static void iser_handle_comp_error(struct iser_desc *desc)
+static void iser_handle_comp_error(struct iser_tx_desc *desc,
+				struct iser_conn *ib_conn)
 {
-	struct iser_dto  *dto     = &desc->dto;
-	struct iser_conn *ib_conn = dto->ib_conn;
-
-	iser_dto_buffs_release(dto);
-
-	if (desc->type == ISCSI_RX) {
-		kfree(desc->data);
+	if (desc && desc->type == ISCSI_TX_DATAOUT)
 		kmem_cache_free(ig.desc_cache, desc);
-		atomic_dec(&ib_conn->post_recv_buf_count);
-	} else { /* type is TX control/command/dataout */
-		if (desc->type == ISCSI_TX_DATAOUT)
-			kmem_cache_free(ig.desc_cache, desc);
-		atomic_dec(&ib_conn->post_send_buf_count);
-	}
 
-	if (atomic_read(&ib_conn->post_recv_buf_count) == 0 &&
+	if (ib_conn->post_recv_buf_count == 0 &&
 	    atomic_read(&ib_conn->post_send_buf_count) == 0) {
 		/* getting here when the state is UP means that the conn is *
 		 * being terminated asynchronously from the iSCSI layer's   *
 		 * perspective.                                             */
 		if (iser_conn_state_comp_exch(ib_conn, ISER_CONN_UP,
 		    ISER_CONN_TERMINATING))
-			iscsi_conn_failure(ib_conn->iser_conn->iscsi_conn,
+			iscsi_conn_failure(ib_conn->iscsi_conn,
 					   ISCSI_ERR_CONN_FAILED);
 
-		/* complete the termination process if disconnect event was delivered *
-		 * note there are no more non completed posts to the QP               */
-		if (ib_conn->disc_evt_flag) {
-			ib_conn->state = ISER_CONN_DOWN;
-			wake_up_interruptible(&ib_conn->wait);
+		/* no more non completed posts to the QP, complete the
+		 * termination process w.o worrying on disconnect event */
+		ib_conn->state = ISER_CONN_DOWN;
+		wake_up_interruptible(&ib_conn->wait);
+	}
+}
+
+static int iser_drain_tx_cq(struct iser_device  *device, int cq_index)
+{
+	struct ib_cq  *cq = device->tx_cq[cq_index];
+	struct ib_wc  wc;
+	struct iser_tx_desc *tx_desc;
+	struct iser_conn *ib_conn;
+	int completed_tx = 0;
+
+	while (ib_poll_cq(cq, 1, &wc) == 1) {
+		tx_desc	= (struct iser_tx_desc *) (unsigned long) wc.wr_id;
+		ib_conn = wc.qp->qp_context;
+		if (wc.status == IB_WC_SUCCESS) {
+			if (wc.opcode == IB_WC_SEND)
+				iser_snd_completion(tx_desc, ib_conn);
+			else
+				iser_err("expected opcode %d got %d\n",
+					IB_WC_SEND, wc.opcode);
+		} else {
+			iser_err("tx id %llx status %d vend_err %x\n",
+				 wc.wr_id, wc.status, wc.vendor_err);
+			if (wc.wr_id != ISER_FASTREG_LI_WRID) {
+				atomic_dec(&ib_conn->post_send_buf_count);
+				iser_handle_comp_error(tx_desc, ib_conn);
+			}
 		}
+		completed_tx++;
 	}
+	return completed_tx;
 }
 
+
 static void iser_cq_tasklet_fn(unsigned long data)
 {
-	 struct iser_device  *device = (struct iser_device *)data;
-	 struct ib_cq	     *cq = device->cq;
+	struct iser_cq_desc *cq_desc = (struct iser_cq_desc *)data;
+	struct iser_device  *device = cq_desc->device;
+	int cq_index = cq_desc->cq_index;
+	struct ib_cq	     *cq = device->rx_cq[cq_index];
 	 struct ib_wc	     wc;
-	 struct iser_desc    *desc;
+	 struct iser_rx_desc *desc;
 	 unsigned long	     xfer_len;
+	struct iser_conn *ib_conn;
+	int completed_tx, completed_rx = 0;
+
+	/* First do tx drain, so in a case where we have rx flushes and a successful
+	 * tx completion we will still go through completion error handling.
+	 */
+	completed_tx = iser_drain_tx_cq(device, cq_index);
 
 	while (ib_poll_cq(cq, 1, &wc) == 1) {
-		desc	 = (struct iser_desc *) (unsigned long) wc.wr_id;
+		desc	 = (struct iser_rx_desc *) (unsigned long) wc.wr_id;
 		BUG_ON(desc == NULL);
-
+		ib_conn = wc.qp->qp_context;
 		if (wc.status == IB_WC_SUCCESS) {
-			if (desc->type == ISCSI_RX) {
+			if (wc.opcode == IB_WC_RECV) {
 				xfer_len = (unsigned long)wc.byte_len;
-				iser_rcv_completion(desc, xfer_len);
-			} else /* type == ISCSI_TX_CONTROL/SCSI_CMD/DOUT */
-				iser_snd_completion(desc);
+				iser_rcv_completion(desc, xfer_len, ib_conn);
+			} else
+				iser_err("expected opcode %d got %d\n",
+					IB_WC_RECV, wc.opcode);
 		} else {
-			iser_err("comp w. error op %d status %d\n",desc->type,wc.status);
-			iser_handle_comp_error(desc);
+			if (wc.status != IB_WC_WR_FLUSH_ERR)
+				iser_err("rx id %llx status %d vend_err %x\n",
+					wc.wr_id, wc.status, wc.vendor_err);
+			ib_conn->post_recv_buf_count--;
+			iser_handle_comp_error(NULL, ib_conn);
 		}
+		completed_rx++;
+		if (!(completed_rx & 63))
+			completed_tx += iser_drain_tx_cq(device, cq_index);
 	}
 	/* #warning "it is assumed here that arming CQ only once its empty" *
 	 * " would not cause interrupts to be missed"                       */
 	ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
+
+	iser_dbg("got %d rx %d tx completions\n", completed_rx, completed_tx);
 }
 
 static void iser_cq_callback(struct ib_cq *cq, void *cq_context)
 {
-	struct iser_device  *device = (struct iser_device *)cq_context;
+	struct iser_cq_desc *cq_desc = (struct iser_cq_desc *)cq_context;
+	struct iser_device  *device = cq_desc->device;
+	int cq_index = cq_desc->cq_index;
+
+	tasklet_schedule(&device->cq_tasklet[cq_index]);
+}
+
+u8 iser_check_task_pi_status(struct iscsi_iser_task *iser_task,
+			     enum iser_data_dir cmd_dir, sector_t *sector)
+{
+	struct iser_mem_reg *reg = &iser_task->rdma_regd[cmd_dir].reg;
+	struct fast_reg_descriptor *desc = reg->mem_h;
+	unsigned long sector_size = iser_task->sc->device->sector_size;
+	struct ib_mr_status mr_status;
+	int ret;
 
-	tasklet_schedule(&device->cq_tasklet);
+	if (desc && desc->reg_indicators & ISER_FASTREG_PROTECTED) {
+		desc->reg_indicators &= ~ISER_FASTREG_PROTECTED;
+		ret = ib_check_mr_status(desc->pi_ctx->sig_mr,
+					 IB_MR_CHECK_SIG_STATUS, &mr_status);
+		if (ret) {
+			pr_err("ib_check_mr_status failed, ret %d\n", ret);
+			goto err;
+		}
+
+		if (mr_status.fail_status & IB_MR_CHECK_SIG_STATUS) {
+			sector_t sector_off = mr_status.sig_err.sig_err_offset;
+
+			do_div(sector_off, sector_size + 8);
+			*sector = scsi_get_lba(iser_task->sc) + sector_off;
+
+			pr_err("PI error found type %d at sector %llx "
+			       "expected %x vs actual %x\n",
+			       mr_status.sig_err.err_type,
+			       (unsigned long long)*sector,
+			       mr_status.sig_err.expected,
+			       mr_status.sig_err.actual);
+
+			switch (mr_status.sig_err.err_type) {
+			case IB_SIG_BAD_GUARD:
+				return 0x1;
+			case IB_SIG_BAD_REFTAG:
+				return 0x3;
+			case IB_SIG_BAD_APPTAG:
+				return 0x2;
+			}
+		}
+	}
+
+	return 0;
+err:
+	/* Not alot we can do here, return ambiguous guard error */
+	return 0x1;
 }