[dpdk-dev] [PATCH] net/vhost: Add function to retreive the 'vid' for a given port id.

[Ciara Loftus]

In some cases when using the vHost PMD, certain vHost library functions
may still need to be accessed. One such example is the
rte_vhost_get_queue_num function which returns the number of virtqueues
reported by the guest - information which is not exposed by the PMD.

This commit introduces a new rte_eth_vhost function that returns the
'vid' associated with a given port id. This allows the PMD user to call
vHost library functions which require the 'vid' value.

Signed-off-by: Ciara Loftus <ciara.loftus at intel.com>
---
 drivers/net/vhost/rte_eth_vhost.c           | 29 +++++++++++++++++++++++++++++
 drivers/net/vhost/rte_eth_vhost.h           |  9 +++++++++
 drivers/net/vhost/rte_pmd_vhost_version.map |  6 ++++++
 3 files changed, 44 insertions(+)

diff --git a/drivers/net/vhost/rte_eth_vhost.c b/drivers/net/vhost/rte_eth_vhost.c
index 7539cd4..091517d 100644
--- a/drivers/net/vhost/rte_eth_vhost.c
+++ b/drivers/net/vhost/rte_eth_vhost.c
@@ -428,6 +428,35 @@ rte_eth_vhost_get_queue_event(uint8_t port_id,
 	return -1;
 }
 
+int
+rte_eth_vhost_get_vid_from_port_id(uint8_t port_id)
+{
+	struct internal_list *list;
+	struct rte_eth_dev *eth_dev;
+	struct vhost_queue *vq;
+	int vid = -1;
+
+	if (!rte_eth_dev_is_valid_port(port_id))
+		return -1;
+
+	pthread_mutex_lock(&internal_list_lock);
+
+	TAILQ_FOREACH(list, &internal_list, next) {
+		eth_dev = list->eth_dev;
+		if (eth_dev->data->port_id == port_id) {
+			vq = eth_dev->data->rx_queues[0];
+			if (vq) {
+				vid = vq->vid;
+			}
+			break;
+		}
+	}
+
+	pthread_mutex_unlock(&internal_list_lock);
+
+	return vid;
+}
+
 static void *
 vhost_driver_session(void *param __rte_unused)
 {
diff --git a/drivers/net/vhost/rte_eth_vhost.h b/drivers/net/vhost/rte_eth_vhost.h
index ff5d877..7c98b1a 100644
--- a/drivers/net/vhost/rte_eth_vhost.h
+++ b/drivers/net/vhost/rte_eth_vhost.h
@@ -102,6 +102,15 @@ struct rte_eth_vhost_queue_event {
 int rte_eth_vhost_get_queue_event(uint8_t port_id,
 		struct rte_eth_vhost_queue_event *event);
 
+/**
+ * Get the 'vid' value associated with the specified port.
+ *
+ * @return
+ *  - On success, the 'vid' associated with 'port_id'.
+ *  - On failure, a negative value.
+ */
+int rte_eth_vhost_get_vid_from_port_id(uint8_t port_id);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/drivers/net/vhost/rte_pmd_vhost_version.map b/drivers/net/vhost/rte_pmd_vhost_version.map
index 65bf3a8..0533a83 100644
--- a/drivers/net/vhost/rte_pmd_vhost_version.map
+++ b/drivers/net/vhost/rte_pmd_vhost_version.map
@@ -8,3 +8,9 @@ DPDK_16.04 {
 
 	local: *;
 };
+
+DPDK_16.11 {
+	global:
+
+	rte_eth_vhost_get_vid_from_port_id;
+}
-- 
2.4.3