Commit a61280dd authored by Longpeng's avatar Longpeng Committed by Michael S. Tsirkin
Browse files

vdpa: support exposing the config size to userspace 



- GET_CONFIG_SIZE: return the size of the virtio config space.

The size contains the fields which are conditional on feature
bits.

Acked-by: default avatarJason Wang <jasowang@redhat.com>
Signed-off-by: default avatarLongpeng <longpeng2@huawei.com>
Link: https://lore.kernel.org/r/20220315032553.455-2-longpeng2@huawei.com


Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Reviewed-by: default avatarStefano Garzarella <sgarzare@redhat.com>
parent f1781bed

drivers/vhost/vdpa.c

+17 −0
Original line number Diff line number Diff line
@@ -358,6 +358,20 @@ static long vhost_vdpa_get_iova_range(struct vhost_vdpa *v, u32 __user *argp) 
	return 0;

}



static long vhost_vdpa_get_config_size(struct vhost_vdpa *v, u32 __user *argp)

{

	struct vdpa_device *vdpa = v->vdpa;

	const struct vdpa_config_ops *ops = vdpa->config;

	u32 size;



	size = ops->get_config_size(vdpa);



	if (copy_to_user(argp, &size, sizeof(size)))

		return -EFAULT;



	return 0;

}



static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd,

				   void __user *argp)

{
@@ -495,6 +509,9 @@ static long vhost_vdpa_unlocked_ioctl(struct file *filep, 
	case VHOST_VDPA_GET_IOVA_RANGE:

		r = vhost_vdpa_get_iova_range(v, argp);

		break;

	case VHOST_VDPA_GET_CONFIG_SIZE:

		r = vhost_vdpa_get_config_size(v, argp);

		break;

	default:

		r = vhost_dev_ioctl(&v->vdev, cmd, argp);

		if (r == -ENOIOCTLCMD)

include/linux/vdpa.h

+2 −1
Original line number Diff line number Diff line
@@ -207,7 +207,8 @@ struct vdpa_map_file { 
 * @reset:			Reset device

 *				@vdev: vdpa device

 *				Returns integer: success (0) or error (< 0)

 * @get_config_size:		Get the size of the configuration space

 * @get_config_size:		Get the size of the configuration space includes

 *				fields that are conditional on feature bits.

 *				@vdev: vdpa device

 *				Returns size_t: configuration size

 * @get_config:			Read from device specific configuration space

include/uapi/linux/vhost.h

+4 −0
Original line number Diff line number Diff line
@@ -150,4 +150,8 @@ 
/* 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)



#endif