[07/14] vhost: replace device ID in applications

diff --git a/examples/vdpa/main.c b/examples/vdpa/main.c
index 8d707c9e2d..4417500d9b 100644
--- a/examples/vdpa/main.c
+++ b/examples/vdpa/main.c
@@ -26,7 +26,7 @@ 
 
 struct vdpa_port {
 	char ifname[MAX_PATH_LEN];
-	int did;
+	struct rte_vdpa_device *dev;
 	int vid;
 	uint64_t flags;
 };
@@ -101,16 +101,23 @@  static int
 new_device(int vid)
 {
 	char ifname[MAX_PATH_LEN];
+	struct rte_device *dev;
 	int i;
 
 	rte_vhost_get_ifname(vid, ifname, sizeof(ifname));
 	for (i = 0; i < MAX_VDPA_SAMPLE_PORTS; i++) {
-		if (strncmp(ifname, vports[i].ifname, MAX_PATH_LEN) == 0) {
-			printf("\nnew port %s, did: %d\n",
-					ifname, vports[i].did);
-			vports[i].vid = vid;
-			break;
+		if (strncmp(ifname, vports[i].ifname, MAX_PATH_LEN))
+			continue;
+
+		dev = rte_vdpa_get_rte_device(vports[i].dev);
+		if (!dev) {
+			RTE_LOG(ERR, VDPA,
+				"Failed to get generic device for port %d\n", i);
+			continue;
 		}
+		printf("\nnew port %s, device : %s\n", ifname, dev->name);
+		vports[i].vid = vid;
+		break;
 	}
 
 	if (i >= MAX_VDPA_SAMPLE_PORTS)
@@ -122,16 +129,24 @@  new_device(int vid)
 static void
 destroy_device(int vid)
 {
+	struct rte_device *dev;
 	char ifname[MAX_PATH_LEN];
 	int i;
 
 	rte_vhost_get_ifname(vid, ifname, sizeof(ifname));
 	for (i = 0; i < MAX_VDPA_SAMPLE_PORTS; i++) {
-		if (strcmp(ifname, vports[i].ifname) == 0) {
-			printf("\ndestroy port %s, did: %d\n",
-					ifname, vports[i].did);
-			break;
+		if (strncmp(ifname, vports[i].ifname, MAX_PATH_LEN))
+			continue;
+
+		dev = rte_vdpa_get_rte_device(vports[i].dev);
+		if (!dev) {
+			RTE_LOG(ERR, VDPA,
+				"Failed to get generic device for port %d\n", i);
+			continue;
 		}
+
+		printf("\ndestroy port %s, device: %s\n", ifname, dev->name);
+		break;
 	}
 }
 
@@ -145,8 +160,6 @@  start_vdpa(struct vdpa_port *vport)
 {
 	int ret;
 	char *socket_path = vport->ifname;
-	struct rte_vdpa_device *vdev;
-	int did = vport->did;
 
 	if (client_mode)
 		vport->flags |= RTE_VHOST_USER_CLIENT;
@@ -170,13 +183,7 @@  start_vdpa(struct vdpa_port *vport)
 			"register driver ops failed: %s\n",
 			socket_path);
 
-	vdev = rte_vdpa_get_device(did);
-	if (!vdev)
-		rte_exit(EXIT_FAILURE,
-			"vDPA device retrieval failed: %p\n",
-			vdev);
-
-	ret = rte_vhost_driver_attach_vdpa_device(socket_path, vdev);
+	ret = rte_vhost_driver_attach_vdpa_device(socket_path, vport->dev);
 	if (ret != 0)
 		rte_exit(EXIT_FAILURE,
 			"attach vdpa device failed: %s\n",
@@ -274,35 +281,31 @@  static void cmd_list_vdpa_devices_parsed(
 		struct cmdline *cl,
 		__rte_unused void *data)
 {
-	int did;
 	uint32_t queue_num;
 	uint64_t features;
 	struct rte_vdpa_device *vdev;
 	struct rte_device *dev;
 	struct rte_dev_iterator dev_iter;
 
-	cmdline_printf(cl, "device id\tdevice name\tqueue num\tsupported features\n");
+	cmdline_printf(cl, "device name\tqueue num\tsupported features\n");
 	RTE_DEV_FOREACH(dev, "class=vdpa", &dev_iter) {
-		did = rte_vdpa_find_device_id_by_name(dev->name);
-		if (did < 0)
-			continue;
-		vdev = rte_vdpa_get_device(did);
+		vdev = rte_vdpa_find_device_by_name(dev->name);
 		if (!vdev)
 			continue;
 		if (vdev->ops->get_queue_num(vdev, &queue_num) < 0) {
 			RTE_LOG(ERR, VDPA,
 				"failed to get vdpa queue number "
-				"for device id %d.\n", did);
+				"for device %s.\n", dev->name);
 			continue;
 		}
 		if (vdev->ops->get_features(vdev, &features) < 0) {
 			RTE_LOG(ERR, VDPA,
 				"failed to get vdpa features "
-				"for device id %d.\n", did);
+				"for device %s.\n", dev->name);
 			continue;
 		}
-		cmdline_printf(cl, "%d\t\t%s\t\t%" PRIu32 "\t\t0x%" PRIx64 "\n",
-			did, dev->name, queue_num, features);
+		cmdline_printf(cl, "%s\t\t%" PRIu32 "\t\t0x%" PRIx64 "\n",
+			dev->name, queue_num, features);
 	}
 }
 
@@ -330,18 +333,18 @@  static void cmd_create_vdpa_port_parsed(void *parsed_result,
 		struct cmdline *cl,
 		__rte_unused void *data)
 {
-	int did;
+	struct rte_vdpa_device *dev;
 	struct cmd_create_result *res = parsed_result;
 
 	rte_strscpy(vports[devcnt].ifname, res->socket_path, MAX_PATH_LEN);
-	did = rte_vdpa_find_device_id_by_name(res->bdf);
-	if (did < 0) {
+	dev = rte_vdpa_find_device_by_name(res->bdf);
+	if (dev == NULL) {
 		cmdline_printf(cl, "Unable to find vdpa device id for %s.\n",
 				res->bdf);
 		return;
 	}
 
-	vports[devcnt].did = did;
+	vports[devcnt].dev = dev;
 
 	if (start_vdpa(&vports[devcnt]) == 0)
 		devcnt++;
@@ -403,9 +406,9 @@  int
 main(int argc, char *argv[])
 {
 	char ch;
-	int did;
 	int ret;
 	struct cmdline *cl;
+	struct rte_vdpa_device *vdev;
 	struct rte_device *dev;
 	struct rte_dev_iterator dev_iter;
 
@@ -434,12 +437,12 @@  main(int argc, char *argv[])
 		cmdline_stdin_exit(cl);
 	} else {
 		RTE_DEV_FOREACH(dev, "class=vdpa", &dev_iter) {
-			did = rte_vdpa_find_device_id_by_name(dev->name);
-			if (did < 0) {
-				rte_panic("Failed to find device id for %s\n",
+			vdev = rte_vdpa_find_device_by_name(dev->name);
+			if (vdev == NULL) {
+				rte_panic("Failed to find vDPA dev for %s\n",
 						dev->name);
 			}
-			vports[devcnt].did = did;
+			vports[devcnt].dev = vdev;
 			snprintf(vports[devcnt].ifname, MAX_PATH_LEN, "%s%d",
 					iface, devcnt);
 
diff --git a/lib/librte_vhost/rte_vdpa.h b/lib/librte_vhost/rte_vdpa.h
index e7c785102d..6188bf6483 100644
--- a/lib/librte_vhost/rte_vdpa.h
+++ b/lib/librte_vhost/rte_vdpa.h
@@ -113,11 +113,26 @@  rte_vdpa_unregister_device(struct rte_vdpa_device *);
  * @param name
  *  the vdpa device name
  * @return
- *  device id on success, -1 on failure
+ *  vDPA device pointer on success, NULL on failure
  */
 __rte_experimental
-int
-rte_vdpa_find_device_id_by_name(const char *name);
+struct rte_vdpa_device *
+rte_vdpa_find_device_by_name(const char *name);
+
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice
+ *
+ * Get the generic device from the vdpa device
+ *
+ * @param vdpa_dev
+ *  the vdpa device pointer
+ * @return
+ *  generic device pointer on success, NULL on failure
+ */
+__rte_experimental
+struct rte_device *
+rte_vdpa_get_rte_device(struct rte_vdpa_device *vdpa_dev);
 
 /**
  * @warning
diff --git a/lib/librte_vhost/rte_vhost_version.map b/lib/librte_vhost/rte_vhost_version.map
index 4872bc4f35..43caab7553 100644
--- a/lib/librte_vhost/rte_vhost_version.map
+++ b/lib/librte_vhost/rte_vhost_version.map
@@ -66,5 +66,6 @@  EXPERIMENTAL {
 	rte_vhost_get_vhost_ring_inflight;
 	rte_vhost_get_vring_base_from_inflight;
 	rte_vhost_slave_config_change;
-	rte_vdpa_find_device_id_by_name;
+	rte_vdpa_find_device_by_name;
+	rte_vdpa_get_rte_device;
 };
diff --git a/lib/librte_vhost/vdpa.c b/lib/librte_vhost/vdpa.c
index 5ad96fe8a6..9ec5677a78 100644
--- a/lib/librte_vhost/vdpa.c
+++ b/lib/librte_vhost/vdpa.c
@@ -40,14 +40,14 @@  rte_vdpa_find_device_id(struct rte_vdpa_device *dev)
 	return -1;
 }
 
-int
-rte_vdpa_find_device_id_by_name(const char *name)
+struct rte_vdpa_device *
+rte_vdpa_find_device_by_name(const char *name)
 {
 	struct rte_vdpa_device *dev;
 	int i;
 
 	if (name == NULL)
-		return -1;
+		return NULL;
 
 	for (i = 0; i < MAX_VHOST_DEVICE; ++i) {
 		dev = &vdpa_devices[i];
@@ -55,10 +55,19 @@  rte_vdpa_find_device_id_by_name(const char *name)
 			continue;
 
 		if (strcmp(dev->device->name, name) == 0)
-			return i;
+			return dev;
 	}
 
-	return -1;
+	return NULL;
+}
+
+struct rte_device *
+rte_vdpa_get_rte_device(struct rte_vdpa_device *vdpa_dev)
+{
+	if (vdpa_dev == NULL)
+		return NULL;
+
+	return vdpa_dev->device;
 }
 
 struct rte_vdpa_device *