[dpdk-dev] [PATCH 3/3] vdpa/mlx5: recreate a virtq becoming enabled

[Matan Azrad <matan@mellanox.com>]

The virtq configurations may be changed when it moves from disabled
state to enabled state.

Listen to the state callback even if the device is not configured.
Recreate the virtq when it moves from disabled state to enabled state
and when the device is configured.

Signed-off-by: Matan Azrad <matan@mellanox.com>
Acked-by: Viacheslav Ovsiienko <viacheslavo@mellanox.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
---
 drivers/vdpa/mlx5/mlx5_vdpa.c       | 12 +++--
 drivers/vdpa/mlx5/mlx5_vdpa.h       | 39 +++++++++++++++--
 drivers/vdpa/mlx5/mlx5_vdpa_lm.c    | 17 +++++---
 drivers/vdpa/mlx5/mlx5_vdpa_steer.c | 87 ++++++++++++++++++-------------------
 drivers/vdpa/mlx5/mlx5_vdpa_virtq.c | 59 ++++++++++++++++++++++---
 5 files changed, 146 insertions(+), 68 deletions(-)

diff --git a/drivers/vdpa/mlx5/mlx5_vdpa.c b/drivers/vdpa/mlx5/mlx5_vdpa.c
index 70327df..9f7353d 100644
--- a/drivers/vdpa/mlx5/mlx5_vdpa.c
+++ b/drivers/vdpa/mlx5/mlx5_vdpa.c
@@ -121,13 +121,11 @@
 		DRV_LOG(ERR, "Invalid device id: %d.", did);
 		return -EINVAL;
 	}
-	if (!priv->configured || vring >= RTE_MIN((int)priv->nr_virtqs,
-	    (int)priv->caps.max_num_virtio_queues * 2) ||
-	    !priv->virtqs[vring].virtq) {
-		DRV_LOG(ERR, "Invalid or unconfigured vring id: %d.", vring);
-		return -EINVAL;
+	if (vring >= (int)priv->caps.max_num_virtio_queues * 2) {
+		DRV_LOG(ERR, "Too big vring id: %d.", vring);
+		return -E2BIG;
 	}
-	return mlx5_vdpa_virtq_enable(&priv->virtqs[vring], state);
+	return mlx5_vdpa_virtq_enable(priv, vring, state);
 }
 
 static int
@@ -206,7 +204,7 @@
 	if (priv->configured)
 		ret |= mlx5_vdpa_lm_log(priv);
 	mlx5_vdpa_cqe_event_unset(priv);
-	ret |= mlx5_vdpa_steer_unset(priv);
+	mlx5_vdpa_steer_unset(priv);
 	mlx5_vdpa_virtqs_release(priv);
 	mlx5_vdpa_event_qp_global_release(priv);
 	mlx5_vdpa_mem_dereg(priv);
diff --git a/drivers/vdpa/mlx5/mlx5_vdpa.h b/drivers/vdpa/mlx5/mlx5_vdpa.h
index 0edd688..fcc216a 100644
--- a/drivers/vdpa/mlx5/mlx5_vdpa.h
+++ b/drivers/vdpa/mlx5/mlx5_vdpa.h
@@ -127,6 +127,24 @@ struct mlx5_vdpa_priv {
 	struct mlx5_vdpa_virtq virtqs[];
 };
 
+/*
+ * Check whether virtq is for traffic receive.
+ * According to VIRTIO_NET Spec the virtqueues index identity its type by:
+ * 0 receiveq1
+ * 1 transmitq1
+ * ...
+ * 2(N-1) receiveqN
+ * 2(N-1)+1 transmitqN
+ * 2N controlq
+ */
+static inline uint8_t
+is_virtq_recvq(int virtq_index, int nr_vring)
+{
+	if (virtq_index % 2 == 0 && virtq_index != nr_vring - 1)
+		return 1;
+	return 0;
+}
+
 /**
  * Release all the prepared memory regions and all their related resources.
  *
@@ -223,15 +241,17 @@ int mlx5_vdpa_event_qp_create(struct mlx5_vdpa_priv *priv, uint16_t desc_n,
 /**
  * Enable\Disable virtq..
  *
- * @param[in] virtq
- *   The vdpa driver private virtq structure.
+ * @param[in] priv
+ *   The vdpa driver private structure.
+ * @param[in] index
+ *   The virtq index.
  * @param[in] enable
  *   Set to enable, otherwise disable.
  *
  * @return
  *   0 on success, a negative value otherwise.
  */
-int mlx5_vdpa_virtq_enable(struct mlx5_vdpa_virtq *virtq, int enable);
+int mlx5_vdpa_virtq_enable(struct mlx5_vdpa_priv *priv, int index, int enable);
 
 /**
  * Unset steering and release all its related resources- stop traffic.
@@ -239,7 +259,18 @@ int mlx5_vdpa_event_qp_create(struct mlx5_vdpa_priv *priv, uint16_t desc_n,
  * @param[in] priv
  *   The vdpa driver private structure.
  */
-int mlx5_vdpa_steer_unset(struct mlx5_vdpa_priv *priv);
+void mlx5_vdpa_steer_unset(struct mlx5_vdpa_priv *priv);
+
+/**
+ * Update steering according to the received queues status.
+ *
+ * @param[in] priv
+ *   The vdpa driver private structure.
+ *
+ * @return
+ *   0 on success, a negative value otherwise.
+ */
+int mlx5_vdpa_steer_update(struct mlx5_vdpa_priv *priv);
 
 /**
  * Setup steering and all its related resources to enable RSS traffic from the
diff --git a/drivers/vdpa/mlx5/mlx5_vdpa_lm.c b/drivers/vdpa/mlx5/mlx5_vdpa_lm.c
index 26b7ce1..460e01d 100644
--- a/drivers/vdpa/mlx5/mlx5_vdpa_lm.c
+++ b/drivers/vdpa/mlx5/mlx5_vdpa_lm.c
@@ -19,7 +19,8 @@
 
 	for (i = 0; i < priv->nr_virtqs; ++i) {
 		attr.queue_index = i;
-		if (mlx5_devx_cmd_modify_virtq(priv->virtqs[i].virtq, &attr)) {
+		if (!priv->virtqs[i].virtq ||
+		    mlx5_devx_cmd_modify_virtq(priv->virtqs[i].virtq, &attr)) {
 			DRV_LOG(ERR, "Failed to modify virtq %d logging.", i);
 			return -1;
 		}
@@ -68,7 +69,8 @@
 	attr.dirty_bitmap_mkey = mr->mkey->id;
 	for (i = 0; i < priv->nr_virtqs; ++i) {
 		attr.queue_index = i;
-		if (mlx5_devx_cmd_modify_virtq(priv->virtqs[i].virtq, &attr)) {
+		if (!priv->virtqs[i].virtq ||
+		    mlx5_devx_cmd_modify_virtq(priv->virtqs[i].virtq, &attr)) {
 			DRV_LOG(ERR, "Failed to modify virtq %d for lm.", i);
 			goto err;
 		}
@@ -102,9 +104,14 @@
 	if (!RTE_VHOST_NEED_LOG(features))
 		return 0;
 	for (i = 0; i < priv->nr_virtqs; ++i) {
-		ret = mlx5_vdpa_virtq_stop(priv, i);
-		if (ret) {
-			DRV_LOG(ERR, "Failed to stop virtq %d.", i);
+		if (priv->virtqs[i].virtq) {
+			ret = mlx5_vdpa_virtq_stop(priv, i);
+			if (ret) {
+				DRV_LOG(ERR, "Failed to stop virtq %d.", i);
+				return -1;
+			}
+		} else {
+			DRV_LOG(ERR, "virtq %d is not created.", i);
 			return -1;
 		}
 		rte_vhost_log_used_vring(priv->vid, i, 0,
diff --git a/drivers/vdpa/mlx5/mlx5_vdpa_steer.c b/drivers/vdpa/mlx5/mlx5_vdpa_steer.c
index 96ffc21..406c7be 100644
--- a/drivers/vdpa/mlx5/mlx5_vdpa_steer.c
+++ b/drivers/vdpa/mlx5/mlx5_vdpa_steer.c
@@ -12,10 +12,9 @@
 #include "mlx5_vdpa_utils.h"
 #include "mlx5_vdpa.h"
 
-int
-mlx5_vdpa_steer_unset(struct mlx5_vdpa_priv *priv)
+static void
+mlx5_vdpa_rss_flows_destroy(struct mlx5_vdpa_priv *priv)
 {
-	int ret __rte_unused;
 	unsigned i;
 
 	for (i = 0; i < RTE_DIM(priv->steer.rss); ++i) {
@@ -40,6 +39,12 @@
 			priv->steer.rss[i].matcher = NULL;
 		}
 	}
+}
+
+void
+mlx5_vdpa_steer_unset(struct mlx5_vdpa_priv *priv)
+{
+	mlx5_vdpa_rss_flows_destroy(priv);
 	if (priv->steer.tbl) {
 		claim_zero(mlx5_glue->dr_destroy_flow_tbl(priv->steer.tbl));
 		priv->steer.tbl = NULL;
@@ -52,27 +57,13 @@
 		claim_zero(mlx5_devx_cmd_destroy(priv->steer.rqt));
 		priv->steer.rqt = NULL;
 	}
-	return 0;
 }
 
+#define MLX5_VDPA_DEFAULT_RQT_SIZE 512
 /*
- * According to VIRTIO_NET Spec the virtqueues index identity its type by:
- * 0 receiveq1
- * 1 transmitq1
- * ...
- * 2(N-1) receiveqN
- * 2(N-1)+1 transmitqN
- * 2N controlq
+ * Return the number of queues configured to the table on success, otherwise
+ * -1 on error.
  */
-static uint8_t
-is_virtq_recvq(int virtq_index, int nr_vring)
-{
-	if (virtq_index % 2 == 0 && virtq_index != nr_vring - 1)
-		return 1;
-	return 0;
-}
-
-#define MLX5_VDPA_DEFAULT_RQT_SIZE 512
 static int
 mlx5_vdpa_rqt_prepare(struct mlx5_vdpa_priv *priv)
 {
@@ -83,7 +74,7 @@
 						      + rqt_n *
 						      sizeof(uint32_t), 0);
 	uint32_t k = 0, j;
-	int ret = 0;
+	int ret = 0, num;
 
 	if (!attr) {
 		DRV_LOG(ERR, "Failed to allocate RQT attributes memory.");
@@ -92,11 +83,15 @@
 	}
 	for (i = 0; i < priv->nr_virtqs; i++) {
 		if (is_virtq_recvq(i, priv->nr_virtqs) &&
-		    priv->virtqs[i].enable) {
+		    priv->virtqs[i].enable && priv->virtqs[i].virtq) {
 			attr->rq_list[k] = priv->virtqs[i].virtq->id;
 			k++;
 		}
 	}
+	if (k == 0)
+		/* No enabled RQ to configure for RSS. */
+		return 0;
+	num = (int)k;
 	for (j = 0; k != rqt_n; ++k, ++j)
 		attr->rq_list[k] = attr->rq_list[j];
 	attr->rq_type = MLX5_INLINE_Q_TYPE_VIRTQ;
@@ -114,26 +109,7 @@
 			DRV_LOG(ERR, "Failed to modify RQT.");
 	}
 	rte_free(attr);
-	return ret;
-}
-
-int
-mlx5_vdpa_virtq_enable(struct mlx5_vdpa_virtq *virtq, int enable)
-{
-	struct mlx5_vdpa_priv *priv = virtq->priv;
-	int ret = 0;
-
-	DRV_LOG(INFO, "Update virtq %d status %sable -> %sable.", virtq->index,
-		virtq->enable ? "en" : "dis", enable ? "en" : "dis");
-	if (virtq->enable == !!enable)
-		return 0;
-	virtq->enable = !!enable;
-	if (is_virtq_recvq(virtq->index, priv->nr_virtqs)) {
-		ret = mlx5_vdpa_rqt_prepare(priv);
-		if (ret)
-			virtq->enable = !enable;
-	}
-	return ret;
+	return ret ? -1 : num;
 }
 
 static int __rte_unused
@@ -262,11 +238,32 @@
 }
 
 int
+mlx5_vdpa_steer_update(struct mlx5_vdpa_priv *priv)
+{
+	int ret = mlx5_vdpa_rqt_prepare(priv);
+
+	if (ret == 0) {
+		mlx5_vdpa_rss_flows_destroy(priv);
+		if (priv->steer.rqt) {
+			claim_zero(mlx5_devx_cmd_destroy(priv->steer.rqt));
+			priv->steer.rqt = NULL;
+		}
+	} else if (ret < 0) {
+		return ret;
+	} else if (!priv->steer.rss[0].flow) {
+		ret = mlx5_vdpa_rss_flows_create(priv);
+		if (ret) {
+			DRV_LOG(ERR, "Cannot create RSS flows.");
+			return -1;
+		}
+	}
+	return 0;
+}
+
+int
 mlx5_vdpa_steer_setup(struct mlx5_vdpa_priv *priv)
 {
 #ifdef HAVE_MLX5DV_DR
-	if (mlx5_vdpa_rqt_prepare(priv))
-		return -1;
 	priv->steer.domain = mlx5_glue->dr_create_domain(priv->ctx,
 						  MLX5DV_DR_DOMAIN_TYPE_NIC_RX);
 	if (!priv->steer.domain) {
@@ -278,7 +275,7 @@
 		DRV_LOG(ERR, "Failed to create table 0 with Rx domain.");
 		goto error;
 	}
-	if (mlx5_vdpa_rss_flows_create(priv))
+	if (mlx5_vdpa_steer_update(priv))
 		goto error;
 	return 0;
 error:
diff --git a/drivers/vdpa/mlx5/mlx5_vdpa_virtq.c b/drivers/vdpa/mlx5/mlx5_vdpa_virtq.c
index 9c0284c..bd48460 100644
--- a/drivers/vdpa/mlx5/mlx5_vdpa_virtq.c
+++ b/drivers/vdpa/mlx5/mlx5_vdpa_virtq.c
@@ -59,9 +59,11 @@
 				usleep(MLX5_VDPA_INTR_RETRIES_USEC);
 			}
 		}
+		virtq->intr_handle.fd = -1;
 	}
 	if (virtq->virtq)
 		claim_zero(mlx5_devx_cmd_destroy(virtq->virtq));
+	virtq->virtq = NULL;
 	for (i = 0; i < RTE_DIM(virtq->umems); ++i) {
 		if (virtq->umems[i].obj)
 			claim_zero(mlx5_glue->devx_umem_dereg
@@ -69,10 +71,9 @@
 		if (virtq->umems[i].buf)
 			rte_free(virtq->umems[i].buf);
 	}
+	memset(&virtq->umems, 0, sizeof(virtq->umems));
 	if (virtq->eqp.fw_qp)
 		mlx5_vdpa_event_qp_destroy(&virtq->eqp);
-	memset(virtq, 0, sizeof(*virtq));
-	virtq->intr_handle.fd = -1;
 	return 0;
 }
 
@@ -81,8 +82,10 @@
 {
 	int i;
 
-	for (i = 0; i < priv->nr_virtqs; i++)
+	for (i = 0; i < priv->nr_virtqs; i++) {
 		mlx5_vdpa_virtq_unset(&priv->virtqs[i]);
+		priv->virtqs[i].enable = 0;
+	}
 	if (priv->tis) {
 		claim_zero(mlx5_devx_cmd_destroy(priv->tis));
 		priv->tis = NULL;
@@ -272,10 +275,7 @@
 		goto error;
 	if (mlx5_vdpa_virtq_modify(virtq, 1))
 		goto error;
-	virtq->enable = 1;
 	virtq->priv = priv;
-	/* Be sure notifications are not missed during configuration. */
-	claim_zero(rte_vhost_enable_guest_notification(priv->vid, index, 1));
 	rte_write32(virtq->index, priv->virtq_db_addr);
 	/* Setup doorbell mapping. */
 	virtq->intr_handle.fd = vq.kickfd;
@@ -402,11 +402,56 @@
 		goto error;
 	}
 	priv->nr_virtqs = nr_vring;
-	for (i = 0; i < nr_vring; i++)
+	for (i = 0; i < nr_vring; i++) {
+		claim_zero(rte_vhost_enable_guest_notification(priv->vid, i,
+							       1));
 		if (mlx5_vdpa_virtq_setup(priv, i))
 			goto error;
+	}
 	return 0;
 error:
 	mlx5_vdpa_virtqs_release(priv);
 	return -1;
 }
+
+int
+mlx5_vdpa_virtq_enable(struct mlx5_vdpa_priv *priv, int index, int enable)
+{
+	struct mlx5_vdpa_virtq *virtq = &priv->virtqs[index];
+	int ret;
+
+	DRV_LOG(INFO, "Update virtq %d status %sable -> %sable.", index,
+		virtq->enable ? "en" : "dis", enable ? "en" : "dis");
+	if (virtq->enable == !!enable)
+		return 0;
+	if (!priv->configured) {
+		virtq->enable = !!enable;
+		return 0;
+	}
+	if (enable) {
+		/* Configuration might have been updated - reconfigure virtq. */
+		if (virtq->virtq) {
+			ret = mlx5_vdpa_virtq_stop(priv, index);
+			if (ret)
+				DRV_LOG(WARNING, "Failed to stop virtq %d.",
+					index);
+			mlx5_vdpa_virtq_unset(virtq);
+		}
+		ret = mlx5_vdpa_virtq_setup(priv, index);
+		if (ret) {
+			DRV_LOG(ERR, "Failed to setup virtq %d.", index);
+			return ret;
+			/* The only case virtq can stay invalid. */
+		}
+	}
+	virtq->enable = !!enable;
+	if (is_virtq_recvq(virtq->index, priv->nr_virtqs)) {
+		/* Need to add received virtq to the RQT table of the TIRs. */
+		ret = mlx5_vdpa_steer_update(priv);
+		if (ret) {
+			virtq->enable = !enable;
+			return ret;
+		}
+	}
+	return 0;
+}
-- 
1.8.3.1