iser-target: Convert to new CQ API

Use the workqueue based CQ type similar to what isert was using previously,
and properly split up the completion handlers.

Note that this also takes special care to handle the magic login WRs
separately, and also renames the submission functions so that it's clear
that they are only to be used for the login buffers.

(Fix up isert_print_wc usage in isert_beacon_done - nab)

Signed-off-by: Christoph Hellwig <hch@lst.de>
[sagig: added iscsi conn reinstatement in non-flush
 error completions and added error completion type print]
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

drivers/infiniband/ulp/isert/ib_isert.c

@@ -59,13 +59,17 @@ isert_reg_rdma(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
 static int
 isert_put_response(struct iscsi_conn *conn, struct iscsi_cmd *cmd);
 static int
-isert_rdma_post_recvl(struct isert_conn *isert_conn);
+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_wait4flush(struct isert_conn *isert_conn);
+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)
@@ -178,12 +182,6 @@ err:
 	return ret;
 }
 
-static void
-isert_cq_event_callback(struct ib_event *e, void *context)
-{
-	isert_dbg("event: %d\n", e->event);
-}
-
 static int
 isert_alloc_rx_descriptors(struct isert_conn *isert_conn)
 {
@@ -213,6 +211,7 @@ isert_alloc_rx_descriptors(struct isert_conn *isert_conn)
 		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;
@@ -251,9 +250,6 @@ isert_free_rx_descriptors(struct isert_conn *isert_conn)
 	isert_conn->rx_descs = NULL;
 }
 
-static void isert_cq_work(struct work_struct *);
-static void isert_cq_callback(struct ib_cq *, void *);
-
 static void
 isert_free_comps(struct isert_device *device)
 {
@@ -262,10 +258,8 @@ isert_free_comps(struct isert_device *device)
 	for (i = 0; i < device->comps_used; i++) {
 		struct isert_comp *comp = &device->comps[i];
 
-		if (comp->cq) {
-			cancel_work_sync(&comp->work);
-			ib_destroy_cq(comp->cq);
-		}
+		if (comp->cq)
+			ib_free_cq(comp->cq);
 	}
 	kfree(device->comps);
 }
@@ -294,28 +288,17 @@ isert_alloc_comps(struct isert_device *device)
 	max_cqe = min(ISER_MAX_CQ_LEN, device->ib_device->attrs.max_cqe);
 
 	for (i = 0; i < device->comps_used; i++) {
-		struct ib_cq_init_attr cq_attr = {};
 		struct isert_comp *comp = &device->comps[i];
 
 		comp->device = device;
-		INIT_WORK(&comp->work, isert_cq_work);
-		cq_attr.cqe = max_cqe;
-		cq_attr.comp_vector = i;
-		comp->cq = ib_create_cq(device->ib_device,
-					isert_cq_callback,
-					isert_cq_event_callback,
-					(void *)comp,
-					&cq_attr);
+		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;
 		}
-
-		ret = ib_req_notify_cq(comp->cq, IB_CQ_NEXT_COMP);
-		if (ret)
-			goto out_cq;
 	}
 
 	return 0;
@@ -726,7 +709,7 @@ isert_connect_request(struct rdma_cm_id *cma_id, struct rdma_cm_event *event)
 	if (ret)
 		goto out_conn_dev;
 
-	ret = isert_rdma_post_recvl(isert_conn);
+	ret = isert_login_post_recv(isert_conn);
 	if (ret)
 		goto out_conn_dev;
 
@@ -984,7 +967,8 @@ isert_post_recvm(struct isert_conn *isert_conn, u32 count)
 
 	for (rx_wr = isert_conn->rx_wr, i = 0; i < count; i++, rx_wr++) {
 		rx_desc = &isert_conn->rx_descs[i];
-		rx_wr->wr_id = (uintptr_t)rx_desc;
+
+		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;
@@ -1006,7 +990,7 @@ 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.wr_cqe = &rx_desc->rx_cqe;
 	rx_wr.sg_list = &rx_desc->rx_sg;
 	rx_wr.num_sge = 1;
 	rx_wr.next = NULL;
@@ -1019,7 +1003,7 @@ isert_post_recv(struct isert_conn *isert_conn, struct iser_rx_desc *rx_desc)
 }
 
 static int
-isert_post_send(struct isert_conn *isert_conn, struct iser_tx_desc *tx_desc)
+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, *send_wr_failed;
@@ -1028,8 +1012,10 @@ isert_post_send(struct isert_conn *isert_conn, struct iser_tx_desc *tx_desc)
 	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_id	= (uintptr_t)tx_desc;
+	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;
@@ -1099,7 +1085,8 @@ isert_init_send_wr(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
 	struct iser_tx_desc *tx_desc = &isert_cmd->tx_desc;
 
 	isert_cmd->rdma_wr.iser_ib_op = ISER_IB_SEND;
-	send_wr->wr_id = (uintptr_t)&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;
@@ -1114,7 +1101,7 @@ isert_init_send_wr(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
 }
 
 static int
-isert_rdma_post_recvl(struct isert_conn *isert_conn)
+isert_login_post_recv(struct isert_conn *isert_conn)
 {
 	struct ib_recv_wr rx_wr, *rx_wr_fail;
 	struct ib_sge sge;
@@ -1128,8 +1115,10 @@ isert_rdma_post_recvl(struct isert_conn *isert_conn)
 	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_id = (uintptr_t)isert_conn->login_req_buf;
+	rx_wr.wr_cqe = &isert_conn->login_req_buf->rx_cqe;
 	rx_wr.sg_list = &sge;
 	rx_wr.num_sge = 1;
 
@@ -1201,12 +1190,12 @@ isert_put_login_tx(struct iscsi_conn *conn, struct iscsi_login *login,
 			goto post_send;
 		}
 
-		ret = isert_rdma_post_recvl(isert_conn);
+		ret = isert_login_post_recv(isert_conn);
 		if (ret)
 			return ret;
 	}
 post_send:
-	ret = isert_post_send(isert_conn, tx_desc);
+	ret = isert_login_post_send(isert_conn, tx_desc);
 	if (ret)
 		return ret;
 
@@ -1549,12 +1538,42 @@ isert_rx_opcode(struct isert_conn *isert_conn, struct iser_rx_desc *rx_desc,
 }
 
 static void
-isert_rx_do_work(struct iser_rx_desc *rx_desc, struct isert_conn *isert_conn)
+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;
+	}
+
+	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) {
@@ -1582,55 +1601,40 @@ isert_rx_do_work(struct iser_rx_desc *rx_desc, struct isert_conn *isert_conn)
 
 	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_rcv_completion(struct iser_rx_desc *desc,
-		     struct isert_conn *isert_conn,
-		     u32 xfer_len)
+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->cm_id->device;
-	struct iscsi_hdr *hdr;
-	u64 rx_dma;
-	int rx_buflen;
-
-	if (desc == isert_conn->login_req_buf) {
-		rx_dma = isert_conn->login_req_dma;
-		rx_buflen = ISER_RX_PAYLOAD_SIZE;
-		isert_dbg("login_buf: Using rx_dma: 0x%llx, rx_buflen: %d\n",
-			 rx_dma, rx_buflen);
-	} else {
-		rx_dma = desc->dma_addr;
-		rx_buflen = ISER_RX_PAYLOAD_SIZE;
-		isert_dbg("req_buf: Using rx_dma: 0x%llx, rx_buflen: %d\n",
-			 rx_dma, rx_buflen);
+
+	if (unlikely(wc->status != IB_WC_SUCCESS)) {
+		isert_print_wc(wc, "login recv");
+		return;
 	}
 
-	ib_dma_sync_single_for_cpu(ib_dev, rx_dma, rx_buflen, DMA_FROM_DEVICE);
+	ib_dma_sync_single_for_cpu(ib_dev, isert_conn->login_req_dma,
+			ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
 
-	hdr = &desc->iscsi_header;
-	isert_dbg("iSCSI opcode: 0x%02x, ITT: 0x%08x, flags: 0x%02x dlen: %d\n",
-		 hdr->opcode, hdr->itt, hdr->flags,
-		 (int)(xfer_len - ISER_HEADERS_LEN));
+	isert_conn->login_req_len = wc->byte_len - ISER_HEADERS_LEN;
 
-	if (desc == isert_conn->login_req_buf) {
-		isert_conn->login_req_len = xfer_len - ISER_HEADERS_LEN;
-		if (isert_conn->conn) {
-			struct iscsi_login *login = isert_conn->conn->conn_login;
+	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);
-	} else {
-		isert_rx_do_work(desc, isert_conn);
+		if (login && !login->first_request)
+			isert_rx_login_req(isert_conn);
 	}
 
-	ib_dma_sync_single_for_device(ib_dev, rx_dma, rx_buflen,
-				      DMA_FROM_DEVICE);
+	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 int
@@ -1879,42 +1883,61 @@ fail_mr_status:
 }
 
 static void
-isert_completion_rdma_write(struct iser_tx_desc *tx_desc,
-			    struct isert_cmd *isert_cmd)
+isert_rdma_write_done(struct ib_cq *cq, struct ib_wc *wc)
 {
-	struct isert_rdma_wr *wr = &isert_cmd->rdma_wr;
-	struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
-	struct se_cmd *se_cmd = &cmd->se_cmd;
-	struct isert_conn *isert_conn = isert_cmd->conn;
+	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 = desc->isert_cmd;
+	struct isert_rdma_wr *wr = &isert_cmd->rdma_wr;
+	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);
+
 	if (wr->fr_desc && wr->fr_desc->ind & ISERT_PROTECTED) {
-		ret = isert_check_pi_status(se_cmd,
-					    wr->fr_desc->pi_ctx->sig_mr);
+		ret = isert_check_pi_status(cmd, wr->fr_desc->pi_ctx->sig_mr);
 		wr->fr_desc->ind &= ~ISERT_PROTECTED;
 	}
 
 	device->unreg_rdma_mem(isert_cmd, isert_conn);
 	wr->rdma_wr_num = 0;
 	if (ret)
-		transport_send_check_condition_and_sense(se_cmd,
-							 se_cmd->pi_err, 0);
+		transport_send_check_condition_and_sense(cmd, cmd->pi_err, 0);
 	else
-		isert_put_response(isert_conn->conn, cmd);
+		isert_put_response(isert_conn->conn, isert_cmd->iscsi_cmd);
 }
 
 static void
-isert_completion_rdma_read(struct iser_tx_desc *tx_desc,
-			   struct isert_cmd *isert_cmd)
+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 = desc->isert_cmd;
 	struct isert_rdma_wr *wr = &isert_cmd->rdma_wr;
 	struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
 	struct se_cmd *se_cmd = &cmd->se_cmd;
-	struct isert_conn *isert_conn = isert_cmd->conn;
-	struct isert_device *device = isert_conn->device;
 	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);
+
 	if (wr->fr_desc && wr->fr_desc->ind & ISERT_PROTECTED) {
 		ret = isert_check_pi_status(se_cmd,
 					    wr->fr_desc->pi_ctx->sig_mr);
@@ -1972,167 +1995,56 @@ isert_do_control_comp(struct work_struct *work)
 }
 
 static void
-isert_response_completion(struct iser_tx_desc *tx_desc,
-			  struct isert_cmd *isert_cmd,
-			  struct isert_conn *isert_conn,
-			  struct ib_device *ib_dev)
+isert_login_send_done(struct ib_cq *cq, struct ib_wc *wc)
 {
-	struct iscsi_cmd *cmd = isert_cmd->iscsi_cmd;
-
-	if (cmd->i_state == ISTATE_SEND_TASKMGTRSP ||
-	    cmd->i_state == ISTATE_SEND_LOGOUTRSP ||
-	    cmd->i_state == ISTATE_SEND_REJECT ||
-	    cmd->i_state == ISTATE_SEND_TEXTRSP) {
-		isert_unmap_tx_desc(tx_desc, ib_dev);
+	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);
 
-		INIT_WORK(&isert_cmd->comp_work, isert_do_control_comp);
-		queue_work(isert_comp_wq, &isert_cmd->comp_work);
-		return;
+	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);
 	}
 
-	cmd->i_state = ISTATE_SENT_STATUS;
-	isert_completion_put(tx_desc, isert_cmd, ib_dev, false);
+	isert_unmap_tx_desc(tx_desc, ib_dev);
 }
 
 static void
-isert_snd_completion(struct iser_tx_desc *tx_desc,
-		      struct isert_conn *isert_conn)
+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->isert_cmd;
-	struct isert_rdma_wr *wr;
 
-	if (!isert_cmd) {
-		isert_unmap_tx_desc(tx_desc, ib_dev);
+	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;
 	}
-	wr = &isert_cmd->rdma_wr;
 
-	isert_dbg("Cmd %p iser_ib_op %d\n", isert_cmd, wr->iser_ib_op);
+	isert_dbg("Cmd %p\n", isert_cmd);
 
-	switch (wr->iser_ib_op) {
-	case ISER_IB_SEND:
-		isert_response_completion(tx_desc, isert_cmd,
-					  isert_conn, ib_dev);
-		break;
-	case ISER_IB_RDMA_WRITE:
-		isert_completion_rdma_write(tx_desc, isert_cmd);
-		break;
-	case ISER_IB_RDMA_READ:
-		isert_completion_rdma_read(tx_desc, isert_cmd);
-		break;
+	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_err("Unknown wr->iser_ib_op: 0x%x\n", wr->iser_ib_op);
-		dump_stack();
+		isert_cmd->iscsi_cmd->i_state = ISTATE_SENT_STATUS;
+		isert_completion_put(tx_desc, isert_cmd, ib_dev, false);
 		break;
 	}
 }
 
-/**
- * is_isert_tx_desc() - Indicate if the completion wr_id
- *     is a TX descriptor or not.
- * @isert_conn: iser connection
- * @wr_id: completion WR identifier
- *
- * Since we cannot rely on wc opcode in FLUSH errors
- * we must work around it by checking if the wr_id address
- * falls in the iser connection rx_descs buffer. If so
- * it is an RX descriptor, otherwize it is a TX.
- */
-static inline bool
-is_isert_tx_desc(struct isert_conn *isert_conn, void *wr_id)
-{
-	void *start = isert_conn->rx_descs;
-	int len = ISERT_QP_MAX_RECV_DTOS * sizeof(*isert_conn->rx_descs);
-
-	if ((wr_id >= start && wr_id < start + len) ||
-	    (wr_id == isert_conn->login_req_buf))
-		return false;
-
-	return true;
-}
-
-static void
-isert_cq_comp_err(struct isert_conn *isert_conn, struct ib_wc *wc)
-{
-	if (wc->wr_id == ISER_BEACON_WRID) {
-		isert_info("conn %p completing wait_comp_err\n",
-			   isert_conn);
-		complete(&isert_conn->wait_comp_err);
-	} else if (is_isert_tx_desc(isert_conn, (void *)(uintptr_t)wc->wr_id)) {
-		struct ib_device *ib_dev = isert_conn->cm_id->device;
-		struct isert_cmd *isert_cmd;
-		struct iser_tx_desc *desc;
-
-		desc = (struct iser_tx_desc *)(uintptr_t)wc->wr_id;
-		isert_cmd = desc->isert_cmd;
-		if (!isert_cmd)
-			isert_unmap_tx_desc(desc, ib_dev);
-		else
-			isert_completion_put(desc, isert_cmd, ib_dev, true);
-	}
-}
-
-static void
-isert_handle_wc(struct ib_wc *wc)
-{
-	struct isert_conn *isert_conn;
-	struct iser_tx_desc *tx_desc;
-	struct iser_rx_desc *rx_desc;
-
-	isert_conn = wc->qp->qp_context;
-	if (likely(wc->status == IB_WC_SUCCESS)) {
-		if (wc->opcode == IB_WC_RECV) {
-			rx_desc = (struct iser_rx_desc *)(uintptr_t)wc->wr_id;
-			isert_rcv_completion(rx_desc, isert_conn, wc->byte_len);
-		} else {
-			tx_desc = (struct iser_tx_desc *)(uintptr_t)wc->wr_id;
-			isert_snd_completion(tx_desc, isert_conn);
-		}
-	} else {
-		if (wc->status != IB_WC_WR_FLUSH_ERR)
-			isert_err("%s (%d): wr id %llx vend_err %x\n",
-				  ib_wc_status_msg(wc->status), wc->status,
-				  wc->wr_id, wc->vendor_err);
-		else
-			isert_dbg("%s (%d): wr id %llx\n",
-				  ib_wc_status_msg(wc->status), wc->status,
-				  wc->wr_id);
-
-		if (wc->wr_id != ISER_FASTREG_LI_WRID)
-			isert_cq_comp_err(isert_conn, wc);
-	}
-}
-
-static void
-isert_cq_work(struct work_struct *work)
-{
-	enum { isert_poll_budget = 65536 };
-	struct isert_comp *comp = container_of(work, struct isert_comp,
-					       work);
-	struct ib_wc *const wcs = comp->wcs;
-	int i, n, completed = 0;
-
-	while ((n = ib_poll_cq(comp->cq, ARRAY_SIZE(comp->wcs), wcs)) > 0) {
-		for (i = 0; i < n; i++)
-			isert_handle_wc(&wcs[i]);
-
-		completed += n;
-		if (completed >= isert_poll_budget)
-			break;
-	}
-
-	ib_req_notify_cq(comp->cq, IB_CQ_NEXT_COMP);
-}
-
-static void
-isert_cq_callback(struct ib_cq *cq, void *context)
-{
-	struct isert_comp *comp = context;
-
-	queue_work(isert_comp_wq, &comp->work);
-}
-
 static int
 isert_post_response(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd)
 {
@@ -2389,7 +2301,8 @@ isert_build_rdma_wr(struct isert_conn *isert_conn, struct isert_cmd *isert_cmd,
 	page_off = offset % PAGE_SIZE;
 
 	rdma_wr->wr.sg_list = ib_sge;
-	rdma_wr->wr.wr_id = (uintptr_t)&isert_cmd->tx_desc;
+	rdma_wr->wr.wr_cqe = &isert_cmd->tx_desc.tx_cqe;
+
 	/*
 	 * Perform mapping of TCM scatterlist memory ib_sge dma_addr.
 	 */
@@ -2472,6 +2385,8 @@ isert_map_rdma(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
 
 		rdma_wr->wr.send_flags = 0;
 		if (wr->iser_ib_op == ISER_IB_RDMA_WRITE) {
+			isert_cmd->tx_desc.tx_cqe.done = isert_rdma_write_done;
+
 			rdma_wr->wr.opcode = IB_WR_RDMA_WRITE;
 			rdma_wr->remote_addr = isert_cmd->read_va + offset;
 			rdma_wr->rkey = isert_cmd->read_stag;
@@ -2480,6 +2395,8 @@ isert_map_rdma(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
 			else
 				rdma_wr->wr.next = &wr->rdma_wr[i + 1].wr;
 		} else {
+			isert_cmd->tx_desc.tx_cqe.done = isert_rdma_read_done;
+
 			rdma_wr->wr.opcode = IB_WR_RDMA_READ;
 			rdma_wr->remote_addr = isert_cmd->write_va + va_offset;
 			rdma_wr->rkey = isert_cmd->write_stag;
@@ -2511,7 +2428,7 @@ isert_inv_rkey(struct ib_send_wr *inv_wr, struct ib_mr *mr)
 	u32 rkey;
 
 	memset(inv_wr, 0, sizeof(*inv_wr));
-	inv_wr->wr_id = ISER_FASTREG_LI_WRID;
+	inv_wr->wr_cqe = NULL;
 	inv_wr->opcode = IB_WR_LOCAL_INV;
 	inv_wr->ex.invalidate_rkey = mr->rkey;
 
@@ -2567,7 +2484,7 @@ isert_fast_reg_mr(struct isert_conn *isert_conn,
 
 	reg_wr.wr.next = NULL;
 	reg_wr.wr.opcode = IB_WR_REG_MR;
-	reg_wr.wr.wr_id = ISER_FASTREG_LI_WRID;
+	reg_wr.wr.wr_cqe = NULL;
 	reg_wr.wr.send_flags = 0;
 	reg_wr.wr.num_sge = 0;
 	reg_wr.mr = mr;
@@ -2678,7 +2595,7 @@ isert_reg_sig_mr(struct isert_conn *isert_conn,
 
 	memset(&sig_wr, 0, sizeof(sig_wr));
 	sig_wr.wr.opcode = IB_WR_REG_SIG_MR;
-	sig_wr.wr.wr_id = ISER_FASTREG_LI_WRID;
+	sig_wr.wr.wr_cqe = NULL;
 	sig_wr.wr.sg_list = &rdma_wr->ib_sg[DATA];
 	sig_wr.wr.num_sge = 1;
 	sig_wr.access_flags = IB_ACCESS_LOCAL_WRITE;
@@ -2833,14 +2750,18 @@ isert_reg_rdma(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
 	rdma_wr = &isert_cmd->rdma_wr.s_rdma_wr;
 	rdma_wr->wr.sg_list = &wr->s_ib_sge;
 	rdma_wr->wr.num_sge = 1;
-	rdma_wr->wr.wr_id = (uintptr_t)&isert_cmd->tx_desc;
+	rdma_wr->wr.wr_cqe = &isert_cmd->tx_desc.tx_cqe;
 	if (wr->iser_ib_op == ISER_IB_RDMA_WRITE) {
+		isert_cmd->tx_desc.tx_cqe.done = isert_rdma_write_done;
+
 		rdma_wr->wr.opcode = IB_WR_RDMA_WRITE;
 		rdma_wr->remote_addr = isert_cmd->read_va;
 		rdma_wr->rkey = isert_cmd->read_stag;
 		rdma_wr->wr.send_flags = !isert_prot_cmd(isert_conn, se_cmd) ?
 				      0 : IB_SEND_SIGNALED;
 	} else {
+		isert_cmd->tx_desc.tx_cqe.done = isert_rdma_read_done;
+
 		rdma_wr->wr.opcode = IB_WR_RDMA_READ;
 		rdma_wr->remote_addr = isert_cmd->write_va;
 		rdma_wr->rkey = isert_cmd->write_stag;
@@ -3302,15 +3223,27 @@ isert_wait4cmds(struct iscsi_conn *conn)
 	}
 }
 
+static void
+isert_beacon_done(struct ib_cq *cq, struct ib_wc *wc)
+{
+	struct isert_conn *isert_conn = wc->qp->qp_context;
+
+	isert_print_wc(wc, "beacon");
+
+	isert_info("conn %p completing wait_comp_err\n", isert_conn);
+	complete(&isert_conn->wait_comp_err);
+}
+
 static void
 isert_wait4flush(struct isert_conn *isert_conn)
 {
 	struct ib_recv_wr *bad_wr;
+	static struct ib_cqe cqe = { .done = isert_beacon_done };
 
 	isert_info("conn %p\n", isert_conn);
 
 	init_completion(&isert_conn->wait_comp_err);
-	isert_conn->beacon.wr_id = ISER_BEACON_WRID;
+	isert_conn->beacon.wr_cqe = &cqe;
 	/* post an indication that all flush errors were consumed */
 	if (ib_post_recv(isert_conn->qp, &isert_conn->beacon, &bad_wr)) {
 		isert_err("conn %p failed to post beacon", isert_conn);

drivers/infiniband/ulp/isert/ib_isert.h

@@ -61,11 +61,10 @@
 				ISERT_MAX_RX_MISC_PDUS)
 
 #define ISER_RX_PAD_SIZE	(ISCSI_DEF_MAX_RECV_SEG_LEN + 4096 - \
-		(ISER_RX_PAYLOAD_SIZE + sizeof(u64) + sizeof(struct ib_sge)))
+		(ISER_RX_PAYLOAD_SIZE + sizeof(u64) + sizeof(struct ib_sge) + \
+		 sizeof(struct ib_cqe)))
 
 #define ISCSI_ISER_SG_TABLESIZE		256
-#define ISER_FASTREG_LI_WRID		0xffffffffffffffffULL
-#define ISER_BEACON_WRID               0xfffffffffffffffeULL
 
 enum isert_desc_type {
 	ISCSI_TX_CONTROL,
@@ -94,20 +93,33 @@ struct iser_rx_desc {
 	char		data[ISCSI_DEF_MAX_RECV_SEG_LEN];
 	u64		dma_addr;
 	struct ib_sge	rx_sg;
+	struct ib_cqe	rx_cqe;
 	char		pad[ISER_RX_PAD_SIZE];
 } __packed;
 
+static inline struct iser_rx_desc *cqe_to_rx_desc(struct ib_cqe *cqe)
+{
+	return container_of(cqe, struct iser_rx_desc, rx_cqe);
+}
+
 struct iser_tx_desc {
 	struct iser_ctrl iser_header;
 	struct iscsi_hdr iscsi_header;
 	enum isert_desc_type type;
 	u64		dma_addr;
 	struct ib_sge	tx_sg[2];
+	struct ib_cqe	tx_cqe;
 	int		num_sge;
 	struct isert_cmd *isert_cmd;
 	struct ib_send_wr send_wr;
 } __packed;
 
+static inline struct iser_tx_desc *cqe_to_tx_desc(struct ib_cqe *cqe)
+{
+	return container_of(cqe, struct iser_tx_desc, tx_cqe);
+}
+
+
 enum isert_indicator {
 	ISERT_PROTECTED		= 1 << 0,
 	ISERT_DATA_KEY_VALID	= 1 << 1,
@@ -217,17 +229,13 @@ struct isert_conn {
  *
  * @device:     pointer to device handle
  * @cq:         completion queue
- * @wcs:        work completion array
  * @active_qps: Number of active QPs attached
  *              to completion context
- * @work:       completion work handle
  */
 struct isert_comp {
 	struct isert_device     *device;
 	struct ib_cq		*cq;
-	struct ib_wc		 wcs[16];
 	int                      active_qps;
-	struct work_struct	 work;
 };
 
 struct isert_device {