Re: [PATCH v2 09/10] vdpa: Support reporting max device virtqueues

Add max_supported_vqs field to struct vdpa_mgmt_dev. Upstream drivers
need to feel this value according to the device capabilities.

This value is reported back in a netlink message when showing a device.

Example:

$ vdpa dev show
vdpa-a: type network mgmtdev auxiliary/mlx5_core.sf.1 vendor_id 5555 \
	max_vqp 3 max_vq_size 256 max_supported_vqs 256

Signed-off-by: Eli Cohen <redacted>
---
  drivers/vdpa/vdpa.c       | 2 ++
  include/linux/vdpa.h      | 1 +
  include/uapi/linux/vdpa.h | 1 +
  3 files changed, 4 insertions(+)

diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c
index 130a8d4aeaed..b9dd693146be 100644
--- a/drivers/vdpa/vdpa.c
+++ b/drivers/vdpa/vdpa.c

@@ -695,6 +695,8 @@ vdpa_dev_fill(struct vdpa_device *vdev, struct sk_buff *msg, u32 portid, u32 seq
  		goto msg_err;
  	if (nla_put_u16(msg, VDPA_ATTR_DEV_MIN_VQ_SIZE, min_vq_size))
  		goto msg_err;
+	if (nla_put_u16(msg, VDPA_ATTR_DEV_MAX_DEV_VQS, vdev->mdev->max_supported_vqs))
+		goto msg_err;
  
  	genlmsg_end(msg, hdr);
  	return 0;

diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
index 9245dfbf1b08..72ea8ad7ba21 100644
--- a/include/linux/vdpa.h
+++ b/include/linux/vdpa.h

@@ -444,6 +444,7 @@ struct vdpa_mgmt_dev {
  	const struct vdpa_mgmtdev_ops *ops;
  	const struct virtio_device_id *id_table;
  	u64 config_attr_mask;
+	u16 max_supported_vqs;
  	struct list_head list;
  };
  

diff --git a/include/uapi/linux/vdpa.h b/include/uapi/linux/vdpa.h
index 23b854e3e5e2..1b758d77e228 100644
--- a/include/uapi/linux/vdpa.h
+++ b/include/uapi/linux/vdpa.h

@@ -42,6 +42,7 @@ enum vdpa_attr {
  	VDPA_ATTR_DEV_MAX_VQ_SIZE,		/* u16 */
  	VDPA_ATTR_DEV_MIN_VQ_SIZE,		/* u16 */
  	VDPA_ATTR_DEV_FLAGS,			/* u64 */
+	VDPA_ATTR_DEV_MAX_DEV_VQS,		/* u16 */