[PATCH v8 07/13] vhost: add API to get vDPA device type

[Andy Pei]

Vhost backend of different devices have different features.
Add a API to get vDPA device type, net device or blk device
currently, so users can set different features for different
kinds of devices.

Signed-off-by: Andy Pei <andy.pei at intel.com>
---
 doc/guides/prog_guide/vhost_lib.rst    |  5 ++++
 doc/guides/rel_notes/release_22_07.rst |  4 ++++
 lib/vhost/rte_vhost.h                  | 17 +++++++++++++
 lib/vhost/socket.c                     | 44 ++++++++++++++++++++++++++++++++++
 lib/vhost/vdpa_driver.h                |  3 +++
 lib/vhost/version.map                  |  1 +
 6 files changed, 74 insertions(+)

diff --git a/doc/guides/prog_guide/vhost_lib.rst b/doc/guides/prog_guide/vhost_lib.rst
index f287b76..0337b38 100644
--- a/doc/guides/prog_guide/vhost_lib.rst
+++ b/doc/guides/prog_guide/vhost_lib.rst
@@ -282,6 +282,11 @@ The following is an overview of some key Vhost API functions:
   Clear inflight packets which are submitted to DMA engine in vhost async data
   path. Completed packets are returned to applications through ``pkts``.
 
+* ``rte_vhost_driver_get_vdpa_dev_type(path, type)``
+
+  Get device type of vDPA device, such as VDPA_DEVICE_TYPE_NET,
+  VDPA_DEVICE_TYPE_BLK.
+
 Vhost-user Implementations
 --------------------------
 
diff --git a/doc/guides/rel_notes/release_22_07.rst b/doc/guides/rel_notes/release_22_07.rst
index e49cace..9550977 100644
--- a/doc/guides/rel_notes/release_22_07.rst
+++ b/doc/guides/rel_notes/release_22_07.rst
@@ -104,6 +104,10 @@ New Features
   * ``RTE_EVENT_QUEUE_ATTR_WEIGHT``
   * ``RTE_EVENT_QUEUE_ATTR_AFFINITY``
 
+* **Added vhost API to get the device type of a vDPA device.**
+
+  Added an API which can get the device type of vDPA device.
+
 
 Removed Items
 -------------
diff --git a/lib/vhost/rte_vhost.h b/lib/vhost/rte_vhost.h
index c733f85..c977a24 100644
--- a/lib/vhost/rte_vhost.h
+++ b/lib/vhost/rte_vhost.h
@@ -117,6 +117,9 @@
 
 #define RTE_MAX_VHOST_DEVICE	1024
 
+#define VDPA_DEVICE_TYPE_NET 0
+#define VDPA_DEVICE_TYPE_BLK 1
+
 struct rte_vdpa_device;
 
 /**
@@ -486,6 +489,20 @@ struct rte_vdpa_device *
 rte_vhost_driver_get_vdpa_device(const char *path);
 
 /**
+ * Get the device type of the vdpa device.
+ *
+ * @param path
+ *  The vhost-user socket file path
+ * @param type
+ *  the device type of the vdpa device
+ * @return
+ *  0 on success, -1 on failure
+ */
+__rte_experimental
+int
+rte_vhost_driver_get_vdpa_dev_type(const char *path, uint32_t *type);
+
+/**
  * Set the feature bits the vhost-user driver supports.
  *
  * @param path
diff --git a/lib/vhost/socket.c b/lib/vhost/socket.c
index b304339..ef0f401 100644
--- a/lib/vhost/socket.c
+++ b/lib/vhost/socket.c
@@ -619,6 +619,50 @@ struct rte_vdpa_device *
 }
 
 int
+rte_vhost_driver_get_vdpa_dev_type(const char *path, uint32_t *type)
+{
+	struct vhost_user_socket *vsocket;
+	struct rte_vdpa_device *vdpa_dev;
+	uint32_t vdpa_type = 0;
+	int ret = 0;
+
+	pthread_mutex_lock(&vhost_user.mutex);
+	vsocket = find_vhost_user_socket(path);
+	if (!vsocket) {
+		VHOST_LOG_CONFIG(ERR,
+				 "(%s) socket file is not registered yet.\n",
+				 path);
+		ret = -1;
+		goto unlock_exit;
+	}
+
+	vdpa_dev = vsocket->vdpa_dev;
+	if (!vdpa_dev) {
+		ret = -1;
+		goto unlock_exit;
+	}
+
+	if (vdpa_dev->ops->get_dev_type) {
+		ret = vdpa_dev->ops->get_dev_type(vdpa_dev, &vdpa_type);
+		if (ret) {
+			VHOST_LOG_CONFIG(ERR,
+					 "(%s) failed to get vdpa dev type for socket file.\n",
+					 path);
+			ret = -1;
+			goto unlock_exit;
+		}
+	} else {
+		vdpa_type = VDPA_DEVICE_TYPE_NET;
+	}
+
+	*type = vdpa_type;
+
+unlock_exit:
+	pthread_mutex_unlock(&vhost_user.mutex);
+	return ret;
+}
+
+int
 rte_vhost_driver_disable_features(const char *path, uint64_t features)
 {
 	struct vhost_user_socket *vsocket;
diff --git a/lib/vhost/vdpa_driver.h b/lib/vhost/vdpa_driver.h
index e59a834..9cbd7cd 100644
--- a/lib/vhost/vdpa_driver.h
+++ b/lib/vhost/vdpa_driver.h
@@ -78,6 +78,9 @@ struct rte_vdpa_dev_ops {
 	/** Set the device configuration space */
 	int (*set_config)(int vid, uint8_t *config, uint32_t offset,
 		      uint32_t size, uint32_t flags);
+
+	/** get device type: net device, blk device... */
+	int (*get_dev_type)(struct rte_vdpa_device *dev, uint32_t *type);
 };
 
 /**
diff --git a/lib/vhost/version.map b/lib/vhost/version.map
index 5841315..583b4f3 100644
--- a/lib/vhost/version.map
+++ b/lib/vhost/version.map
@@ -90,6 +90,7 @@ EXPERIMENTAL {
 
 	# added in 22.07
 	rte_vhost_async_get_inflight_thread_unsafe;
+	rte_vhost_driver_get_vdpa_dev_type;
 
 };
 
-- 
1.8.3.1