RDMA/ocrdma: Fix to work with even a single MSI-X vector

There are cases like SRIOV where can get only one MSI-X vector
allocated for RoCE.  In that case we need to use the vector for both
data plane and control plane.  We need to use EQ create version V2.
Signed-off-by: Naresh Gottumukkala <bgottumukkala@emulex.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

drivers/infiniband/hw/ocrdma/ocrdma.h

@@ -132,8 +132,7 @@ struct ocrdma_dev {
 	struct ocrdma_cq **cq_tbl;
 	struct ocrdma_qp **qp_tbl;
 
-	struct ocrdma_eq meq;
-	struct ocrdma_eq *qp_eq_tbl;
+	struct ocrdma_eq *eq_tbl;
 	int eq_cnt;
 	u16 base_eqid;
 	u16 max_eq;

drivers/infiniband/hw/ocrdma/ocrdma_hw.c

@@ -364,22 +364,6 @@ static void ocrdma_build_q_pages(struct ocrdma_pa *q_pa, int cnt,
 	}
 }
 
-static void ocrdma_assign_eq_vect_gen2(struct ocrdma_dev *dev,
-				       struct ocrdma_eq *eq)
-{
-	/* assign vector and update vector id for next EQ */
-	eq->vector = dev->nic_info.msix.start_vector;
-	dev->nic_info.msix.start_vector += 1;
-}
-
-static void ocrdma_free_eq_vect_gen2(struct ocrdma_dev *dev)
-{
-	/* this assumes that EQs are freed in exactly reverse order
-	 * as its allocation.
-	 */
-	dev->nic_info.msix.start_vector -= 1;
-}
-
 static int ocrdma_mbx_delete_q(struct ocrdma_dev *dev, struct ocrdma_queue_info *q,
 			       int queue_type)
 {
@@ -420,11 +404,8 @@ static int ocrdma_mbx_create_eq(struct ocrdma_dev *dev, struct ocrdma_eq *eq)
 	memset(cmd, 0, sizeof(*cmd));
 	ocrdma_init_mch(&cmd->req, OCRDMA_CMD_CREATE_EQ, OCRDMA_SUBSYS_COMMON,
 			sizeof(*cmd));
-	if (dev->nic_info.dev_family == OCRDMA_GEN2_FAMILY)
-		cmd->req.rsvd_version = 0;
-	else
-		cmd->req.rsvd_version = 2;
 
+	cmd->req.rsvd_version = 2;
 	cmd->num_pages = 4;
 	cmd->valid = OCRDMA_CREATE_EQ_VALID;
 	cmd->cnt = 4 << OCRDMA_CREATE_EQ_CNT_SHIFT;
@@ -435,12 +416,7 @@ static int ocrdma_mbx_create_eq(struct ocrdma_dev *dev, struct ocrdma_eq *eq)
 				 NULL);
 	if (!status) {
 		eq->q.id = rsp->vector_eqid & 0xffff;
-		if (dev->nic_info.dev_family == OCRDMA_GEN2_FAMILY) {
-			ocrdma_assign_eq_vect_gen2(dev, eq);
-		} else {
 		eq->vector = (rsp->vector_eqid >> 16) & 0xffff;
-			dev->nic_info.msix.start_vector += 1;
-		}
 		eq->q.created = true;
 	}
 	return status;
@@ -483,8 +459,6 @@ static void _ocrdma_destroy_eq(struct ocrdma_dev *dev, struct ocrdma_eq *eq)
 {
 	if (eq->q.created) {
 		ocrdma_mbx_delete_q(dev, &eq->q, QTYPE_EQ);
-		if (dev->nic_info.dev_family == OCRDMA_GEN2_FAMILY)
-			ocrdma_free_eq_vect_gen2(dev);
 		ocrdma_free_q(dev, &eq->q);
 	}
 }
@@ -503,13 +477,12 @@ static void ocrdma_destroy_eq(struct ocrdma_dev *dev, struct ocrdma_eq *eq)
 	_ocrdma_destroy_eq(dev, eq);
 }
 
-static void ocrdma_destroy_qp_eqs(struct ocrdma_dev *dev)
+static void ocrdma_destroy_eqs(struct ocrdma_dev *dev)
 {
 	int i;
 
-	/* deallocate the data path eqs */
 	for (i = 0; i < dev->eq_cnt; i++)
-		ocrdma_destroy_eq(dev, &dev->qp_eq_tbl[i]);
+		ocrdma_destroy_eq(dev, &dev->eq_tbl[i]);
 }
 
 static int ocrdma_mbx_mq_cq_create(struct ocrdma_dev *dev,
@@ -598,7 +571,7 @@ static int ocrdma_create_mq(struct ocrdma_dev *dev)
 	if (status)
 		goto alloc_err;
 
-	status = ocrdma_mbx_mq_cq_create(dev, &dev->mq.cq, &dev->meq.q);
+	status = ocrdma_mbx_mq_cq_create(dev, &dev->mq.cq, &dev->eq_tbl[0].q);
 	if (status)
 		goto mbx_cq_free;
 
@@ -1304,19 +1277,19 @@ static u16 ocrdma_bind_eq(struct ocrdma_dev *dev)
 	u16 eq_id;
 
 	mutex_lock(&dev->dev_lock);
-	cq_cnt = dev->qp_eq_tbl[0].cq_cnt;
-	eq_id = dev->qp_eq_tbl[0].q.id;
+	cq_cnt = dev->eq_tbl[0].cq_cnt;
+	eq_id = dev->eq_tbl[0].q.id;
 	/* find the EQ which is has the least number of
 	 * CQs associated with it.
 	 */
 	for (i = 0; i < dev->eq_cnt; i++) {
-		if (dev->qp_eq_tbl[i].cq_cnt < cq_cnt) {
-			cq_cnt = dev->qp_eq_tbl[i].cq_cnt;
-			eq_id = dev->qp_eq_tbl[i].q.id;
+		if (dev->eq_tbl[i].cq_cnt < cq_cnt) {
+			cq_cnt = dev->eq_tbl[i].cq_cnt;
+			eq_id = dev->eq_tbl[i].q.id;
 			selected_eq = i;
 		}
 	}
-	dev->qp_eq_tbl[selected_eq].cq_cnt += 1;
+	dev->eq_tbl[selected_eq].cq_cnt += 1;
 	mutex_unlock(&dev->dev_lock);
 	return eq_id;
 }
@@ -1327,9 +1300,9 @@ static void ocrdma_unbind_eq(struct ocrdma_dev *dev, u16 eq_id)
 
 	mutex_lock(&dev->dev_lock);
 	for (i = 0; i < dev->eq_cnt; i++) {
-		if (dev->qp_eq_tbl[i].q.id != eq_id)
+		if (dev->eq_tbl[i].q.id != eq_id)
 			continue;
-		dev->qp_eq_tbl[i].cq_cnt -= 1;
+		dev->eq_tbl[i].cq_cnt -= 1;
 		break;
 	}
 	mutex_unlock(&dev->dev_lock);
@@ -2434,38 +2407,7 @@ int ocrdma_free_av(struct ocrdma_dev *dev, struct ocrdma_ah *ah)
 	return 0;
 }
 
-static int ocrdma_create_mq_eq(struct ocrdma_dev *dev)
-{
-	int status;
-	int irq;
-	unsigned long flags = 0;
-	int num_eq = 0;
-
-	if (dev->nic_info.intr_mode == BE_INTERRUPT_MODE_INTX) {
-		flags = IRQF_SHARED;
-	} else {
-		num_eq = dev->nic_info.msix.num_vectors -
-				dev->nic_info.msix.start_vector;
-		/* minimum two vectors/eq are required for rdma to work.
-		 * one for control path and one for data path.
-		 */
-		if (num_eq < 2)
-			return -EBUSY;
-	}
-
-	status = ocrdma_create_eq(dev, &dev->meq, OCRDMA_EQ_LEN);
-	if (status)
-		return status;
-	sprintf(dev->meq.irq_name, "ocrdma_mq%d", dev->id);
-	irq = ocrdma_get_irq(dev, &dev->meq);
-	status = request_irq(irq, ocrdma_irq_handler, flags, dev->meq.irq_name,
-			     &dev->meq);
-	if (status)
-		_ocrdma_destroy_eq(dev, &dev->meq);
-	return status;
-}
-
-static int ocrdma_create_qp_eqs(struct ocrdma_dev *dev)
+static int ocrdma_create_eqs(struct ocrdma_dev *dev)
 {
 	int num_eq, i, status = 0;
 	int irq;
@@ -2480,46 +2422,43 @@ static int ocrdma_create_qp_eqs(struct ocrdma_dev *dev)
 		num_eq = min_t(u32, num_eq, num_online_cpus());
 	}
 
-	dev->qp_eq_tbl = kzalloc(sizeof(struct ocrdma_eq) * num_eq, GFP_KERNEL);
-	if (!dev->qp_eq_tbl)
+	if (!num_eq)
+		return -EINVAL;
+
+	dev->eq_tbl = kzalloc(sizeof(struct ocrdma_eq) * num_eq, GFP_KERNEL);
+	if (!dev->eq_tbl)
 		return -ENOMEM;
 
 	for (i = 0; i < num_eq; i++) {
-		status = ocrdma_create_eq(dev, &dev->qp_eq_tbl[i],
+		status = ocrdma_create_eq(dev, &dev->eq_tbl[i],
 					  OCRDMA_EQ_LEN);
 		if (status) {
 			status = -EINVAL;
 			break;
 		}
-		sprintf(dev->qp_eq_tbl[i].irq_name, "ocrdma_qp%d-%d",
+		sprintf(dev->eq_tbl[i].irq_name, "ocrdma%d-%d",
 			dev->id, i);
-		irq = ocrdma_get_irq(dev, &dev->qp_eq_tbl[i]);
+		irq = ocrdma_get_irq(dev, &dev->eq_tbl[i]);
 		status = request_irq(irq, ocrdma_irq_handler, flags,
-				     dev->qp_eq_tbl[i].irq_name,
-				     &dev->qp_eq_tbl[i]);
-		if (status) {
-			_ocrdma_destroy_eq(dev, &dev->qp_eq_tbl[i]);
-			status = -EINVAL;
-			break;
-		}
+				     dev->eq_tbl[i].irq_name,
+				     &dev->eq_tbl[i]);
+		if (status)
+			goto done;
 		dev->eq_cnt += 1;
 	}
 	/* one eq is sufficient for data path to work */
-	if (dev->eq_cnt >= 1)
 	return 0;
-	ocrdma_destroy_qp_eqs(dev);
+done:
+	ocrdma_destroy_eqs(dev);
 	return status;
 }
 
 int ocrdma_init_hw(struct ocrdma_dev *dev)
 {
 	int status;
-	/* set up control path eq */
-	status = ocrdma_create_mq_eq(dev);
-	if (status)
-		return status;
-	/* set up data path eq */
-	status = ocrdma_create_qp_eqs(dev);
+
+	/* create the eqs  */
+	status = ocrdma_create_eqs(dev);
 	if (status)
 		goto qpeq_err;
 	status = ocrdma_create_mq(dev);
@@ -2542,9 +2481,8 @@ int ocrdma_init_hw(struct ocrdma_dev *dev)
 conf_err:
 	ocrdma_destroy_mq(dev);
 mq_err:
-	ocrdma_destroy_qp_eqs(dev);
+	ocrdma_destroy_eqs(dev);
 qpeq_err:
-	ocrdma_destroy_eq(dev, &dev->meq);
 	pr_err("%s() status=%d\n", __func__, status);
 	return status;
 }
@@ -2553,10 +2491,9 @@ void ocrdma_cleanup_hw(struct ocrdma_dev *dev)
 {
 	ocrdma_mbx_delete_ah_tbl(dev);
 
-	/* cleanup the data path eqs */
-	ocrdma_destroy_qp_eqs(dev);
+	/* cleanup the eqs */
+	ocrdma_destroy_eqs(dev);
 
 	/* cleanup the control path */
 	ocrdma_destroy_mq(dev);
-	ocrdma_destroy_eq(dev, &dev->meq);
 }