vhost-vdpa: introduce uAPI to get the number of virtqueue groups

Follows the vDPA support for multiple address spaces, this patch
introduce uAPI for the userspace to know the number of virtqueue
groups supported by the vDPA device.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Gautam Dawar <gdawar@xilinx.com>
Message-Id: <20220330180436.24644-12-gdawar@xilinx.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index cd1bee5..92f78df 100644 (file)
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -559,6 +559,10 @@ static long vhost_vdpa_unlocked_ioctl(struct file *filep,
        case VHOST_VDPA_GET_VRING_NUM:
                r = vhost_vdpa_get_vring_num(v, argp);
                break;
+       case VHOST_VDPA_GET_GROUP_NUM:
+               r = copy_to_user(argp, &v->vdpa->ngroups,
+                                sizeof(v->vdpa->ngroups));
+               break;
        case VHOST_SET_LOG_BASE:
        case VHOST_SET_LOG_FD:
                r = -ENOIOCTLCMD;

diff --git a/include/uapi/linux/vhost.h b/include/uapi/linux/vhost.h
index 8f7b4a9..61317c6 100644 (file)
--- a/include/uapi/linux/vhost.h
+++ b/include/uapi/linux/vhost.h
@@ -145,11 +145,13 @@
 /* Get the valid iova range */
 #define VHOST_VDPA_GET_IOVA_RANGE      _IOR(VHOST_VIRTIO, 0x78, \
                                             struct vhost_vdpa_iova_range)
-
 /* Get the config size */
 #define VHOST_VDPA_GET_CONFIG_SIZE     _IOR(VHOST_VIRTIO, 0x79, __u32)
 
 /* Get the count of all virtqueues */
 #define VHOST_VDPA_GET_VQS_COUNT       _IOR(VHOST_VIRTIO, 0x80, __u32)
 
+/* Get the number of virtqueue groups. */
+#define VHOST_VDPA_GET_GROUP_NUM       _IOR(VHOST_VIRTIO, 0x81, __u32)
+
 #endif