Merge git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending

Pull SCSI target fixes from Nicholas Bellinger:
 "This includes a iser-target series from Jenny + Sagi @ Mellanox that
  addresses the few remaining active I/O shutdown bugs, along with a
  patch to support zero-copy for immediate data payloads that gives a
  nice performance improvement for small block WRITEs.

  Also included are some recent >= v4.2 regression bug-fixes.  The most
  notable is a RCU conversion regression for SPC-3 PR registrations, and
  recent removal of obsolete RFC-3720 markers that introduced a login
  regression bug with MSFT iSCSI initiators.

  Thanks to everyone who has been testing + reporting bugs for v4.x"

* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
  iscsi-target: Avoid OFMarker + IFMarker negotiation
  target: Make TCM_WRITE_PROTECT failure honor D_SENSE bit
  target: Fix target_sense_desc_format NULL pointer dereference
  target: Propigate backend read-only to core_tpg_add_lun
  target: Fix PR registration + APTPL RCU conversion regression
  iser-target: Skip data copy if all the command data comes as immediate
  iser-target: Change the recv buffers posting logic
  iser-target: Fix pending connections handling in target stack shutdown sequnce
  iser-target: Remove np_ prefix from isert_np members
  iser-target: Remove unused variables
  iser-target: Put the reference on commands waiting for unsol data
  iser-target: remove command with state ISTATE_REMOVE

9 files changed, 299 insertions, 166 deletions

diff --git a/drivers/infiniband/ulp/isert/ib_isert.c b/drivers/infiniband/ulp/isert/ib_isert.c
index 403bd29443b8..aa59037d7504 100644
--- a/drivers/infiniband/ulp/isert/ib_isert.c
+++ b/drivers/infiniband/ulp/isert/ib_isert.c
@@ -238,8 +238,6 @@ isert_alloc_rx_descriptors(struct isert_conn *isert_conn)
 		rx_sg->lkey = device->pd->local_dma_lkey;
 	}
 
-	isert_conn->rx_desc_head = 0;
-
 	return 0;
 
 dma_map_fail:
@@ -634,7 +632,7 @@ static void
 isert_init_conn(struct isert_conn *isert_conn)
 {
 	isert_conn->state = ISER_CONN_INIT;
-	INIT_LIST_HEAD(&isert_conn->accept_node);
+	INIT_LIST_HEAD(&isert_conn->node);
 	init_completion(&isert_conn->login_comp);
 	init_completion(&isert_conn->login_req_comp);
 	init_completion(&isert_conn->wait);
@@ -762,28 +760,15 @@ isert_connect_request(struct rdma_cm_id *cma_id, struct rdma_cm_event *event)
 	ret = isert_rdma_post_recvl(isert_conn);
 	if (ret)
 		goto out_conn_dev;
-	/*
-	 * Obtain the second reference now before isert_rdma_accept() to
-	 * ensure that any initiator generated REJECT CM event that occurs
-	 * asynchronously won't drop the last reference until the error path
-	 * in iscsi_target_login_sess_out() does it's ->iscsit_free_conn() ->
-	 * isert_free_conn() -> isert_put_conn() -> kref_put().
-	 */
-	if (!kref_get_unless_zero(&isert_conn->kref)) {
-		isert_warn("conn %p connect_release is running\n", isert_conn);
-		goto out_conn_dev;
-	}
 
 	ret = isert_rdma_accept(isert_conn);
 	if (ret)
 		goto out_conn_dev;
 
-	mutex_lock(&isert_np->np_accept_mutex);
-	list_add_tail(&isert_conn->accept_node, &isert_np->np_accept_list);
-	mutex_unlock(&isert_np->np_accept_mutex);
+	mutex_lock(&isert_np->mutex);
+	list_add_tail(&isert_conn->node, &isert_np->accepted);
+	mutex_unlock(&isert_np->mutex);
 
-	isert_info("np %p: Allow accept_np to continue\n", np);
-	up(&isert_np->np_sem);
 	return 0;
 
 out_conn_dev:
@@ -831,13 +816,21 @@ 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);
-	if (isert_conn->state != ISER_CONN_FULL_FEATURE)
-		isert_conn->state = ISER_CONN_UP;
+	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
@@ -903,14 +896,14 @@ isert_np_cma_handler(struct isert_np *isert_np,
 
 	switch (event) {
 	case RDMA_CM_EVENT_DEVICE_REMOVAL:
-		isert_np->np_cm_id = NULL;
+		isert_np->cm_id = NULL;
 		break;
 	case RDMA_CM_EVENT_ADDR_CHANGE:
-		isert_np->np_cm_id = isert_setup_id(isert_np);
-		if (IS_ERR(isert_np->np_cm_id)) {
+		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->np_cm_id));
-			isert_np->np_cm_id = NULL;
+				  isert_np, PTR_ERR(isert_np->cm_id));
+			isert_np->cm_id = NULL;
 		}
 		break;
 	default:
@@ -929,7 +922,7 @@ isert_disconnected_handler(struct rdma_cm_id *cma_id,
 	struct isert_conn *isert_conn;
 	bool terminating = false;
 
-	if (isert_np->np_cm_id == cma_id)
+	if (isert_np->cm_id == cma_id)
 		return isert_np_cma_handler(cma_id->context, event);
 
 	isert_conn = cma_id->qp->qp_context;
@@ -945,13 +938,13 @@ isert_disconnected_handler(struct rdma_cm_id *cma_id,
 	if (terminating)
 		goto out;
 
-	mutex_lock(&isert_np->np_accept_mutex);
-	if (!list_empty(&isert_conn->accept_node)) {
-		list_del_init(&isert_conn->accept_node);
+	mutex_lock(&isert_np->mutex);
+	if (!list_empty(&isert_conn->node)) {
+		list_del_init(&isert_conn->node);
 		isert_put_conn(isert_conn);
 		queue_work(isert_release_wq, &isert_conn->release_work);
 	}
-	mutex_unlock(&isert_np->np_accept_mutex);
+	mutex_unlock(&isert_np->mutex);
 
 out:
 	return 0;
@@ -962,6 +955,7 @@ isert_connect_error(struct rdma_cm_id *cma_id)
 {
 	struct isert_conn *isert_conn = cma_id->qp->qp_context;
 
+	list_del_init(&isert_conn->node);
 	isert_conn->cm_id = NULL;
 	isert_put_conn(isert_conn);
 
@@ -1006,35 +1000,51 @@ isert_cma_handler(struct rdma_cm_id *cma_id, struct rdma_cm_event *event)
 }
 
 static int
-isert_post_recv(struct isert_conn *isert_conn, u32 count)
+isert_post_recvm(struct isert_conn *isert_conn, u32 count)
 {
 	struct ib_recv_wr *rx_wr, *rx_wr_failed;
 	int i, ret;
-	unsigned int rx_head = isert_conn->rx_desc_head;
 	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[rx_head];
-		rx_wr->wr_id	= (uintptr_t)rx_desc;
-		rx_wr->sg_list	= &rx_desc->rx_sg;
-		rx_wr->num_sge	= 1;
-		rx_wr->next	= rx_wr + 1;
-		rx_head = (rx_head + 1) & (ISERT_QP_MAX_RECV_DTOS - 1);
+		rx_desc = &isert_conn->rx_descs[i];
+		rx_wr->wr_id = (uintptr_t)rx_desc;
+		rx_wr->sg_list = &rx_desc->rx_sg;
+		rx_wr->num_sge = 1;
+		rx_wr->next = rx_wr + 1;
 	}
-
 	rx_wr--;
 	rx_wr->next = NULL; /* mark end of work requests list */
 
 	isert_conn->post_recv_buf_count += count;
 	ret = ib_post_recv(isert_conn->qp, isert_conn->rx_wr,
-				&rx_wr_failed);
+			   &rx_wr_failed);
 	if (ret) {
 		isert_err("ib_post_recv() failed with ret: %d\n", ret);
 		isert_conn->post_recv_buf_count -= count;
-	} else {
-		isert_dbg("Posted %d RX buffers\n", count);
-		isert_conn->rx_desc_head = rx_head;
 	}
+
+	return ret;
+}
+
+static int
+isert_post_recv(struct isert_conn *isert_conn, struct iser_rx_desc *rx_desc)
+{
+	struct ib_recv_wr *rx_wr_failed, rx_wr;
+	int ret;
+
+	rx_wr.wr_id = (uintptr_t)rx_desc;
+	rx_wr.sg_list = &rx_desc->rx_sg;
+	rx_wr.num_sge = 1;
+	rx_wr.next = NULL;
+
+	isert_conn->post_recv_buf_count++;
+	ret = ib_post_recv(isert_conn->qp, &rx_wr, &rx_wr_failed);
+	if (ret) {
+		isert_err("ib_post_recv() failed with ret: %d\n", ret);
+		isert_conn->post_recv_buf_count--;
+	}
+
 	return ret;
 }
 
@@ -1205,7 +1215,8 @@ isert_put_login_tx(struct iscsi_conn *conn, struct iscsi_login *login,
 			if (ret)
 				return ret;
 
-			ret = isert_post_recv(isert_conn, ISERT_MIN_POSTED_RX);
+			ret = isert_post_recvm(isert_conn,
+					       ISERT_QP_MAX_RECV_DTOS);
 			if (ret)
 				return ret;
 
@@ -1278,7 +1289,7 @@ isert_rx_login_req(struct isert_conn *isert_conn)
 }
 
 static struct iscsi_cmd
-*isert_allocate_cmd(struct iscsi_conn *conn)
+*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;
@@ -1292,6 +1303,7 @@ static struct iscsi_cmd
 	isert_cmd = iscsit_priv_cmd(cmd);
 	isert_cmd->conn = isert_conn;
 	isert_cmd->iscsi_cmd = cmd;
+	isert_cmd->rx_desc = rx_desc;
 
 	return cmd;
 }
@@ -1303,9 +1315,9 @@ isert_handle_scsi_cmd(struct isert_conn *isert_conn,
 {
 	struct iscsi_conn *conn = isert_conn->conn;
 	struct iscsi_scsi_req *hdr = (struct iscsi_scsi_req *)buf;
-	struct scatterlist *sg;
 	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)
@@ -1314,7 +1326,10 @@ isert_handle_scsi_cmd(struct isert_conn *isert_conn,
 	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;
@@ -1326,13 +1341,20 @@ isert_handle_scsi_cmd(struct isert_conn *isert_conn,
 	if (!imm_data)
 		return 0;
 
-	sg = &cmd->se_cmd.t_data_sg[0];
-	sg_nents = max(1UL, DIV_ROUND_UP(imm_data_len, PAGE_SIZE));
-
-	isert_dbg("Copying Immediate SG: %p sg_nents: %u from %p imm_data_len: %d\n",
-		  sg, sg_nents, &rx_desc->data[0], imm_data_len);
-
-	sg_copy_from_buffer(sg, sg_nents, &rx_desc->data[0], imm_data_len);
+	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;
 
@@ -1407,6 +1429,15 @@ isert_handle_iscsi_dataout(struct isert_conn *isert_conn,
 	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;
 }
 
@@ -1479,7 +1510,7 @@ isert_rx_opcode(struct isert_conn *isert_conn, struct iser_rx_desc *rx_desc,
 
 	switch (opcode) {
 	case ISCSI_OP_SCSI_CMD:
-		cmd = isert_allocate_cmd(conn);
+		cmd = isert_allocate_cmd(conn, rx_desc);
 		if (!cmd)
 			break;
 
@@ -1493,7 +1524,7 @@ isert_rx_opcode(struct isert_conn *isert_conn, struct iser_rx_desc *rx_desc,
 					rx_desc, (unsigned char *)hdr);
 		break;
 	case ISCSI_OP_NOOP_OUT:
-		cmd = isert_allocate_cmd(conn);
+		cmd = isert_allocate_cmd(conn, rx_desc);
 		if (!cmd)
 			break;
 
@@ -1506,7 +1537,7 @@ isert_rx_opcode(struct isert_conn *isert_conn, struct iser_rx_desc *rx_desc,
 						(unsigned char *)hdr);
 		break;
 	case ISCSI_OP_SCSI_TMFUNC:
-		cmd = isert_allocate_cmd(conn);
+		cmd = isert_allocate_cmd(conn, rx_desc);
 		if (!cmd)
 			break;
 
@@ -1514,22 +1545,20 @@ isert_rx_opcode(struct isert_conn *isert_conn, struct iser_rx_desc *rx_desc,
 						(unsigned char *)hdr);
 		break;
 	case ISCSI_OP_LOGOUT:
-		cmd = isert_allocate_cmd(conn);
+		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) {
+		if (be32_to_cpu(hdr->ttt) != 0xFFFFFFFF)
 			cmd = iscsit_find_cmd_from_itt(conn, hdr->itt);
-			if (!cmd)
-				break;
-		} else {
-			cmd = isert_allocate_cmd(conn);
-			if (!cmd)
-				break;
-		}
+		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,
@@ -1589,7 +1618,7 @@ isert_rcv_completion(struct iser_rx_desc *desc,
 	struct ib_device *ib_dev = isert_conn->cm_id->device;
 	struct iscsi_hdr *hdr;
 	u64 rx_dma;
-	int rx_buflen, outstanding;
+	int rx_buflen;
 
 	if ((char *)desc == isert_conn->login_req_buf) {
 		rx_dma = isert_conn->login_req_dma;
@@ -1629,22 +1658,6 @@ isert_rcv_completion(struct iser_rx_desc *desc,
 				      DMA_FROM_DEVICE);
 
 	isert_conn->post_recv_buf_count--;
-	isert_dbg("Decremented post_recv_buf_count: %d\n",
-		  isert_conn->post_recv_buf_count);
-
-	if ((char *)desc == isert_conn->login_req_buf)
-		return;
-
-	outstanding = isert_conn->post_recv_buf_count;
-	if (outstanding + ISERT_MIN_POSTED_RX <= ISERT_QP_MAX_RECV_DTOS) {
-		int err, count = min(ISERT_QP_MAX_RECV_DTOS - outstanding,
-				ISERT_MIN_POSTED_RX);
-		err = isert_post_recv(isert_conn, count);
-		if (err) {
-			isert_err("isert_post_recv() count: %d failed, %d\n",
-			       count, err);
-		}
-	}
 }
 
 static int
@@ -2156,6 +2169,12 @@ isert_post_response(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd)
 	struct ib_send_wr *wr_failed;
 	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,
 			   &wr_failed);
 	if (ret) {
@@ -2950,6 +2969,12 @@ isert_put_datain(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
 				   &isert_cmd->tx_desc.send_wr);
 		isert_cmd->rdma_wr.s_send_wr.next = &isert_cmd->tx_desc.send_wr;
 		wr->send_wr_num += 1;
+
+		rc = isert_post_recv(isert_conn, isert_cmd->rx_desc);
+		if (rc) {
+			isert_err("ib_post_recv failed with %d\n", rc);
+			return rc;
+		}
 	}
 
 	rc = ib_post_send(isert_conn->qp, wr->send_wr, &wr_failed);
@@ -2999,9 +3024,16 @@ isert_get_dataout(struct iscsi_conn *conn, struct iscsi_cmd *cmd, bool recovery)
 static int
 isert_immediate_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
 {
-	int ret;
+	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;
@@ -3106,10 +3138,10 @@ isert_setup_np(struct iscsi_np *np,
 		isert_err("Unable to allocate struct isert_np\n");
 		return -ENOMEM;
 	}
-	sema_init(&isert_np->np_sem, 0);
-	mutex_init(&isert_np->np_accept_mutex);
-	INIT_LIST_HEAD(&isert_np->np_accept_list);
-	init_completion(&isert_np->np_login_comp);
+	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;
 
 	/*
@@ -3125,7 +3157,7 @@ isert_setup_np(struct iscsi_np *np,
 		goto out;
 	}
 
-	isert_np->np_cm_id = isert_lid;
+	isert_np->cm_id = isert_lid;
 	np->np_context = isert_np;
 
 	return 0;
@@ -3214,7 +3246,7 @@ isert_accept_np(struct iscsi_np *np, struct iscsi_conn *conn)
 	int ret;
 
 accept_wait:
-	ret = down_interruptible(&isert_np->np_sem);
+	ret = down_interruptible(&isert_np->sem);
 	if (ret)
 		return -ENODEV;
 
@@ -3231,15 +3263,15 @@ accept_wait:
 	}
 	spin_unlock_bh(&np->np_thread_lock);
 
-	mutex_lock(&isert_np->np_accept_mutex);
-	if (list_empty(&isert_np->np_accept_list)) {
-		mutex_unlock(&isert_np->np_accept_mutex);
+	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->np_accept_list,
-			struct isert_conn, accept_node);
-	list_del_init(&isert_conn->accept_node);
-	mutex_unlock(&isert_np->np_accept_mutex);
+	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;
@@ -3257,28 +3289,39 @@ isert_free_np(struct iscsi_np *np)
 	struct isert_np *isert_np = np->np_context;
 	struct isert_conn *isert_conn, *n;
 
-	if (isert_np->np_cm_id)
-		rdma_destroy_id(isert_np->np_cm_id);
+	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 np_accept_list.
+	 * up in accepted and pending lists.
 	 */
-	mutex_lock(&isert_np->np_accept_mutex);
-	if (!list_empty(&isert_np->np_accept_list)) {
-		isert_info("Still have isert connections, cleaning up...\n");
+	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->np_accept_list,
-					 accept_node) {
+					 &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->np_accept_mutex);
+	mutex_unlock(&isert_np->mutex);
 
 	np->np_context = NULL;
 	kfree(isert_np);
@@ -3345,6 +3388,41 @@ isert_wait4flush(struct isert_conn *isert_conn)
 	wait_for_completion(&isert_conn->wait_comp_err);
 }
 
+/**
+ * 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;
@@ -3363,8 +3441,9 @@ static void isert_wait_conn(struct iscsi_conn *conn)
 	isert_conn_terminate(isert_conn);
 	mutex_unlock(&isert_conn->mutex);
 
-	isert_wait4cmds(conn);
 	isert_wait4flush(isert_conn);
+	isert_put_unsol_pending_cmds(conn);
+	isert_wait4cmds(conn);
 	isert_wait4logout(isert_conn);
 
 	queue_work(isert_release_wq, &isert_conn->release_work);
diff --git a/drivers/infiniband/ulp/isert/ib_isert.h b/drivers/infiniband/ulp/isert/ib_isert.h
index 6a04ba3c0f72..c5b99bcecbcf 100644
--- a/drivers/infiniband/ulp/isert/ib_isert.h
+++ b/drivers/infiniband/ulp/isert/ib_isert.h
@@ -113,7 +113,6 @@ enum {
 };
 
 struct isert_rdma_wr {
-	struct list_head	wr_list;
 	struct isert_cmd	*isert_cmd;
 	enum iser_ib_op_code	iser_ib_op;
 	struct ib_sge		*ib_sge;
@@ -134,14 +133,13 @@ struct isert_cmd {
 	uint64_t		write_va;
 	u64			pdu_buf_dma;
 	u32			pdu_buf_len;
-	u32			read_va_off;
-	u32			write_va_off;
-	u32			rdma_wr_num;
 	struct isert_conn	*conn;
 	struct iscsi_cmd	*iscsi_cmd;
 	struct iser_tx_desc	tx_desc;
+	struct iser_rx_desc	*rx_desc;
 	struct isert_rdma_wr	rdma_wr;
 	struct work_struct	comp_work;
+	struct scatterlist	sg;
 };
 
 struct isert_device;
@@ -159,11 +157,10 @@ struct isert_conn {
 	u64			login_req_dma;
 	int			login_req_len;
 	u64			login_rsp_dma;
-	unsigned int		rx_desc_head;
 	struct iser_rx_desc	*rx_descs;
-	struct ib_recv_wr	rx_wr[ISERT_MIN_POSTED_RX];
+	struct ib_recv_wr	rx_wr[ISERT_QP_MAX_RECV_DTOS];
 	struct iscsi_conn	*conn;
-	struct list_head	accept_node;
+	struct list_head	node;
 	struct completion	login_comp;
 	struct completion	login_req_comp;
 	struct iser_tx_desc	login_tx_desc;
@@ -222,9 +219,9 @@ struct isert_device {
 
 struct isert_np {
 	struct iscsi_np         *np;
-	struct semaphore	np_sem;
-	struct rdma_cm_id	*np_cm_id;
-	struct mutex		np_accept_mutex;
-	struct list_head	np_accept_list;
-	struct completion	np_login_comp;
+	struct semaphore	sem;
+	struct rdma_cm_id	*cm_id;
+	struct mutex		mutex;
+	struct list_head	accepted;
+	struct list_head	pending;
 };
diff --git a/drivers/target/iscsi/iscsi_target_parameters.c b/drivers/target/iscsi/iscsi_target_parameters.c
index e8a52f7d6204..51d1734d5390 100644
--- a/drivers/target/iscsi/iscsi_target_parameters.c
+++ b/drivers/target/iscsi/iscsi_target_parameters.c
@@ -407,6 +407,7 @@ int iscsi_create_default_params(struct iscsi_param_list **param_list_ptr)
 			TYPERANGE_UTF8, USE_INITIAL_ONLY);
 	if (!param)
 		goto out;
+
 	/*
 	 * Extra parameters for ISER from RFC-5046
 	 */
@@ -496,9 +497,9 @@ int iscsi_set_keys_to_negotiate(
 		} else if (!strcmp(param->name, SESSIONTYPE)) {
 			SET_PSTATE_NEGOTIATE(param);
 		} else if (!strcmp(param->name, IFMARKER)) {
-			SET_PSTATE_NEGOTIATE(param);
+			SET_PSTATE_REJECT(param);
 		} else if (!strcmp(param->name, OFMARKER)) {
-			SET_PSTATE_NEGOTIATE(param);
+			SET_PSTATE_REJECT(param);
 		} else if (!strcmp(param->name, IFMARKINT)) {
 			SET_PSTATE_REJECT(param);
 		} else if (!strcmp(param->name, OFMARKINT)) {
diff --git a/drivers/target/target_core_device.c b/drivers/target/target_core_device.c
index dcc424ac35d4..88ea4e4f124b 100644
--- a/drivers/target/target_core_device.c
+++ b/drivers/target/target_core_device.c
@@ -62,22 +62,13 @@ transport_lookup_cmd_lun(struct se_cmd *se_cmd, u64 unpacked_lun)
 	struct se_session *se_sess = se_cmd->se_sess;
 	struct se_node_acl *nacl = se_sess->se_node_acl;
 	struct se_dev_entry *deve;
+	sense_reason_t ret = TCM_NO_SENSE;
 
 	rcu_read_lock();
 	deve = target_nacl_find_deve(nacl, unpacked_lun);
 	if (deve) {
 		atomic_long_inc(&deve->total_cmds);
 
-		if ((se_cmd->data_direction == DMA_TO_DEVICE) &&
-		    (deve->lun_flags & TRANSPORT_LUNFLAGS_READ_ONLY)) {
-			pr_err("TARGET_CORE[%s]: Detected WRITE_PROTECTED LUN"
-				" Access for 0x%08llx\n",
-				se_cmd->se_tfo->get_fabric_name(),
-				unpacked_lun);
-			rcu_read_unlock();
-			return TCM_WRITE_PROTECTED;
-		}
-
 		if (se_cmd->data_direction == DMA_TO_DEVICE)
 			atomic_long_add(se_cmd->data_length,
 					&deve->write_bytes);
@@ -93,6 +84,17 @@ transport_lookup_cmd_lun(struct se_cmd *se_cmd, u64 unpacked_lun)
 
 		percpu_ref_get(&se_lun->lun_ref);
 		se_cmd->lun_ref_active = true;
+
+		if ((se_cmd->data_direction == DMA_TO_DEVICE) &&
+		    (deve->lun_flags & TRANSPORT_LUNFLAGS_READ_ONLY)) {
+			pr_err("TARGET_CORE[%s]: Detected WRITE_PROTECTED LUN"
+				" Access for 0x%08llx\n",
+				se_cmd->se_tfo->get_fabric_name(),
+				unpacked_lun);
+			rcu_read_unlock();
+			ret = TCM_WRITE_PROTECTED;
+			goto ref_dev;
+		}
 	}
 	rcu_read_unlock();
 
@@ -109,12 +111,6 @@ transport_lookup_cmd_lun(struct se_cmd *se_cmd, u64 unpacked_lun)
 				unpacked_lun);
 			return TCM_NON_EXISTENT_LUN;
 		}
-		/*
-		 * Force WRITE PROTECT for virtual LUN 0
-		 */
-		if ((se_cmd->data_direction != DMA_FROM_DEVICE) &&
-		    (se_cmd->data_direction != DMA_NONE))
-			return TCM_WRITE_PROTECTED;
 
 		se_lun = se_sess->se_tpg->tpg_virt_lun0;
 		se_cmd->se_lun = se_sess->se_tpg->tpg_virt_lun0;
@@ -123,6 +119,15 @@ transport_lookup_cmd_lun(struct se_cmd *se_cmd, u64 unpacked_lun)
 
 		percpu_ref_get(&se_lun->lun_ref);
 		se_cmd->lun_ref_active = true;
+
+		/*
+		 * Force WRITE PROTECT for virtual LUN 0
+		 */
+		if ((se_cmd->data_direction != DMA_FROM_DEVICE) &&
+		    (se_cmd->data_direction != DMA_NONE)) {
+			ret = TCM_WRITE_PROTECTED;
+			goto ref_dev;
+		}
 	}
 	/*
 	 * RCU reference protected by percpu se_lun->lun_ref taken above that
@@ -130,6 +135,7 @@ transport_lookup_cmd_lun(struct se_cmd *se_cmd, u64 unpacked_lun)
 	 * pointer can be kfree_rcu() by the final se_lun->lun_group put via
 	 * target_core_fabric_configfs.c:target_fabric_port_release
 	 */
+ref_dev:
 	se_cmd->se_dev = rcu_dereference_raw(se_lun->lun_se_dev);
 	atomic_long_inc(&se_cmd->se_dev->num_cmds);
 
@@ -140,7 +146,7 @@ transport_lookup_cmd_lun(struct se_cmd *se_cmd, u64 unpacked_lun)
 		atomic_long_add(se_cmd->data_length,
 				&se_cmd->se_dev->read_bytes);
 
-	return 0;
+	return ret;
 }
 EXPORT_SYMBOL(transport_lookup_cmd_lun);
 
@@ -427,8 +433,6 @@ void core_disable_device_list_for_node(
 
 	hlist_del_rcu(&orig->link);
 	clear_bit(DEF_PR_REG_ACTIVE, &orig->deve_flags);
-	rcu_assign_pointer(orig->se_lun, NULL);
-	rcu_assign_pointer(orig->se_lun_acl, NULL);
 	orig->lun_flags = 0;
 	orig->creation_time = 0;
 	orig->attach_count--;
@@ -439,6 +443,9 @@ void core_disable_device_list_for_node(
 	kref_put(&orig->pr_kref, target_pr_kref_release);
 	wait_for_completion(&orig->pr_comp);
 
+	rcu_assign_pointer(orig->se_lun, NULL);
+	rcu_assign_pointer(orig->se_lun_acl, NULL);
+
 	kfree_rcu(orig, rcu_head);
 
 	core_scsi3_free_pr_reg_from_nacl(dev, nacl);
diff --git a/drivers/target/target_core_hba.c b/drivers/target/target_core_hba.c
index 9522960c7fdd..22390e0e046c 100644
--- a/drivers/target/target_core_hba.c
+++ b/drivers/target/target_core_hba.c
@@ -187,5 +187,5 @@ core_delete_hba(struct se_hba *hba)
 
 bool target_sense_desc_format(struct se_device *dev)
 {
-	return dev->transport->get_blocks(dev) > U32_MAX;
+	return (dev) ? dev->transport->get_blocks(dev) > U32_MAX : false;
 }
diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c
index 5a9982f5d5d6..0f19e11acac2 100644
--- a/drivers/target/target_core_iblock.c
+++ b/drivers/target/target_core_iblock.c
@@ -105,6 +105,8 @@ static int iblock_configure_device(struct se_device *dev)
 	mode = FMODE_READ|FMODE_EXCL;
 	if (!ib_dev->ibd_readonly)
 		mode |= FMODE_WRITE;
+	else
+		dev->dev_flags |= DF_READ_ONLY;
 
 	bd = blkdev_get_by_path(ib_dev->ibd_udev_path, mode, ib_dev);
 	if (IS_ERR(bd)) {
diff --git a/drivers/target/target_core_pr.c b/drivers/target/target_core_pr.c
index 5ab7100de17e..e7933115087a 100644
--- a/drivers/target/target_core_pr.c
+++ b/drivers/target/target_core_pr.c
@@ -618,7 +618,7 @@ static struct t10_pr_registration *__core_scsi3_do_alloc_registration(
 	struct se_device *dev,
 	struct se_node_acl *nacl,
 	struct se_lun *lun,
-	struct se_dev_entry *deve,
+	struct se_dev_entry *dest_deve,
 	u64 mapped_lun,
 	unsigned char *isid,
 	u64 sa_res_key,
@@ -640,7 +640,29 @@ static struct t10_pr_registration *__core_scsi3_do_alloc_registration(
 	INIT_LIST_HEAD(&pr_reg->pr_reg_atp_mem_list);
 	atomic_set(&pr_reg->pr_res_holders, 0);
 	pr_reg->pr_reg_nacl = nacl;
-	pr_reg->pr_reg_deve = deve;
+	/*
+	 * For destination registrations for ALL_TG_PT=1 and SPEC_I_PT=1,
+	 * the se_dev_entry->pr_ref will have been already obtained by
+	 * core_get_se_deve_from_rtpi() or __core_scsi3_alloc_registration().
+	 *
+	 * Otherwise, locate se_dev_entry now and obtain a reference until
+	 * registration completes in __core_scsi3_add_registration().
+	 */
+	if (dest_deve) {
+		pr_reg->pr_reg_deve = dest_deve;
+	} else {
+		rcu_read_lock();
+		pr_reg->pr_reg_deve = target_nacl_find_deve(nacl, mapped_lun);
+		if (!pr_reg->pr_reg_deve) {
+			rcu_read_unlock();
+			pr_err("Unable to locate PR deve %s mapped_lun: %llu\n",
+				nacl->initiatorname, mapped_lun);
+			kmem_cache_free(t10_pr_reg_cache, pr_reg);
+			return NULL;
+		}
+		kref_get(&pr_reg->pr_reg_deve->pr_kref);
+		rcu_read_unlock();
+	}
 	pr_reg->pr_res_mapped_lun = mapped_lun;
 	pr_reg->pr_aptpl_target_lun = lun->unpacked_lun;
 	pr_reg->tg_pt_sep_rtpi = lun->lun_rtpi;
@@ -936,17 +958,29 @@ static int __core_scsi3_check_aptpl_registration(
 		    !(strcmp(pr_reg->pr_tport, t_port)) &&
 		     (pr_reg->pr_reg_tpgt == tpgt) &&
 		     (pr_reg->pr_aptpl_target_lun == target_lun)) {
+			/*
+			 * Obtain the ->pr_reg_deve pointer + reference, that
+			 * is released by __core_scsi3_add_registration() below.
+			 */
+			rcu_read_lock();
+			pr_reg->pr_reg_deve = target_nacl_find_deve(nacl, mapped_lun);
+			if (!pr_reg->pr_reg_deve) {
+				pr_err("Unable to locate PR APTPL %s mapped_lun:"
+					" %llu\n", nacl->initiatorname, mapped_lun);
+				rcu_read_unlock();
+				continue;
+			}
+			kref_get(&pr_reg->pr_reg_deve->pr_kref);
+			rcu_read_unlock();
 
 			pr_reg->pr_reg_nacl = nacl;
 			pr_reg->tg_pt_sep_rtpi = lun->lun_rtpi;
-
 			list_del(&pr_reg->pr_reg_aptpl_list);
 			spin_unlock(&pr_tmpl->aptpl_reg_lock);
 			/*
 			 * At this point all of the pointers in *pr_reg will
 			 * be setup, so go ahead and add the registration.
 			 */
-
 			__core_scsi3_add_registration(dev, nacl, pr_reg, 0, 0);
 			/*
 			 * If this registration is the reservation holder,
@@ -1044,18 +1078,11 @@ static void __core_scsi3_add_registration(
 
 	__core_scsi3_dump_registration(tfo, dev, nacl, pr_reg, register_type);
 	spin_unlock(&pr_tmpl->registration_lock);
-
-	rcu_read_lock();
-	deve = pr_reg->pr_reg_deve;
-	if (deve)
-		set_bit(DEF_PR_REG_ACTIVE, &deve->deve_flags);
-	rcu_read_unlock();
-
 	/*
 	 * Skip extra processing for ALL_TG_PT=0 or REGISTER_AND_MOVE.
 	 */
 	if (!pr_reg->pr_reg_all_tg_pt || register_move)
-		return;
+		goto out;
 	/*
 	 * Walk pr_reg->pr_reg_atp_list and add registrations for ALL_TG_PT=1
 	 * allocated in __core_scsi3_alloc_registration()
@@ -1075,19 +1102,31 @@ static void __core_scsi3_add_registration(
 		__core_scsi3_dump_registration(tfo, dev, nacl_tmp, pr_reg_tmp,
 					       register_type);
 		spin_unlock(&pr_tmpl->registration_lock);
-
+		/*
+		 * Drop configfs group dependency reference and deve->pr_kref
+		 * obtained from  __core_scsi3_alloc_registration() code.
+		 */
 		rcu_read_lock();
 		deve = pr_reg_tmp->pr_reg_deve;
-		if (deve)
+		if (deve) {
 			set_bit(DEF_PR_REG_ACTIVE, &deve->deve_flags);
+			core_scsi3_lunacl_undepend_item(deve);
+			pr_reg_tmp->pr_reg_deve = NULL;
+		}
 		rcu_read_unlock();
-
-		/*
-		 * Drop configfs group dependency reference from
-		 * __core_scsi3_alloc_registration()
-		 */
-		core_scsi3_lunacl_undepend_item(pr_reg_tmp->pr_reg_deve);
 	}
+out:
+	/*
+	 * Drop deve->pr_kref obtained in __core_scsi3_do_alloc_registration()
+	 */
+	rcu_read_lock();
+	deve = pr_reg->pr_reg_deve;
+	if (deve) {
+		set_bit(DEF_PR_REG_ACTIVE, &deve->deve_flags);
+		kref_put(&deve->pr_kref, target_pr_kref_release);
+		pr_reg->pr_reg_deve = NULL;
+	}
+	rcu_read_unlock();
 }
 
 static int core_scsi3_alloc_registration(
@@ -1785,9 +1824,11 @@ core_scsi3_decode_spec_i_port(
 			dest_node_acl->initiatorname, i_buf, (dest_se_deve) ?
 			dest_se_deve->mapped_lun : 0);
 
-		if (!dest_se_deve)
+		if (!dest_se_deve) {
+			kref_put(&local_pr_reg->pr_reg_deve->pr_kref,
+				 target_pr_kref_release);
 			continue;
-
+		}
 		core_scsi3_lunacl_undepend_item(dest_se_deve);
 		core_scsi3_nodeacl_undepend_item(dest_node_acl);
 		core_scsi3_tpg_undepend_item(dest_tpg);
@@ -1823,9 +1864,11 @@ out:
 
 		kmem_cache_free(t10_pr_reg_cache, dest_pr_reg);
 
-		if (!dest_se_deve)
+		if (!dest_se_deve) {
+			kref_put(&local_pr_reg->pr_reg_deve->pr_kref,
+				 target_pr_kref_release);
 			continue;
-
+		}
 		core_scsi3_lunacl_undepend_item(dest_se_deve);
 		core_scsi3_nodeacl_undepend_item(dest_node_acl);
 		core_scsi3_tpg_undepend_item(dest_tpg);
diff --git a/drivers/target/target_core_tpg.c b/drivers/target/target_core_tpg.c
index 2d0381dd105c..5fb9dd7f08bb 100644
--- a/drivers/target/target_core_tpg.c
+++ b/drivers/target/target_core_tpg.c
@@ -668,7 +668,10 @@ int core_tpg_add_lun(
 	list_add_tail(&lun->lun_dev_link, &dev->dev_sep_list);
 	spin_unlock(&dev->se_port_lock);
 
-	lun->lun_access = lun_access;
+	if (dev->dev_flags & DF_READ_ONLY)
+		lun->lun_access = TRANSPORT_LUNFLAGS_READ_ONLY;
+	else
+		lun->lun_access = lun_access;
 	if (!(dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE))
 		hlist_add_head_rcu(&lun->link, &tpg->tpg_lun_hlist);
 	mutex_unlock(&tpg->tpg_lun_mutex);
diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h
index ac9bf1c0e42d..5f48754dc36a 100644
--- a/include/target/target_core_base.h
+++ b/include/target/target_core_base.h
@@ -730,6 +730,7 @@ struct se_device {
 #define DF_EMULATED_VPD_UNIT_SERIAL		0x00000004
 #define DF_USING_UDEV_PATH			0x00000008
 #define DF_USING_ALIAS				0x00000010
+#define DF_READ_ONLY				0x00000020
 	/* Physical device queue depth */
 	u32			queue_depth;
 	/* Used for SPC-2 reservations enforce of ISIDs */