Commit bc0d90ee authored by Parav Pandit's avatar Parav Pandit Committed by Michael S. Tsirkin
Browse files

vdpa: Enable user to query vdpa device info 



Enable user to query vdpa device information.

$ vdpa dev add mgmtdev vdpasim_net name foo2

Show the newly created vdpa device by its name:
$ vdpa dev show foo2
foo2: type network mgmtdev vdpasim_net vendor_id 0 max_vqs 2 max_vq_size 256

$ vdpa dev show foo2 -jp
{
    "dev": {
        "foo2": {
            "type": "network",
            "mgmtdev": "vdpasim_net",
            "vendor_id": 0,
            "max_vqs": 2,
            "max_vq_size": 256
        }
    }
}

Signed-off-by: default avatarParav Pandit <parav@nvidia.com>
Reviewed-by: default avatarEli Cohen <elic@nvidia.com>
Reviewed-by: default avatarJason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210105103203.82508-6-parav@nvidia.com

Including a memory leak fix:

Link: https://lore.kernel.org/r/20210217060614.59561-1-parav@nvidia.com


Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
parent 903f7bca

drivers/vdpa/vdpa.c

+131 −0
Original line number Diff line number Diff line
@@ -478,6 +478,131 @@ static int vdpa_nl_cmd_dev_del_set_doit(struct sk_buff *skb, struct genl_info *i 
	return err;

}



static int

vdpa_dev_fill(struct vdpa_device *vdev, struct sk_buff *msg, u32 portid, u32 seq,

	      int flags, struct netlink_ext_ack *extack)

{

	u16 max_vq_size;

	u32 device_id;

	u32 vendor_id;

	void *hdr;

	int err;



	hdr = genlmsg_put(msg, portid, seq, &vdpa_nl_family, flags, VDPA_CMD_DEV_NEW);

	if (!hdr)

		return -EMSGSIZE;



	err = vdpa_nl_mgmtdev_handle_fill(msg, vdev->mdev);

	if (err)

		goto msg_err;



	device_id = vdev->config->get_device_id(vdev);

	vendor_id = vdev->config->get_vendor_id(vdev);

	max_vq_size = vdev->config->get_vq_num_max(vdev);



	err = -EMSGSIZE;

	if (nla_put_string(msg, VDPA_ATTR_DEV_NAME, dev_name(&vdev->dev)))

		goto msg_err;

	if (nla_put_u32(msg, VDPA_ATTR_DEV_ID, device_id))

		goto msg_err;

	if (nla_put_u32(msg, VDPA_ATTR_DEV_VENDOR_ID, vendor_id))

		goto msg_err;

	if (nla_put_u32(msg, VDPA_ATTR_DEV_MAX_VQS, vdev->nvqs))

		goto msg_err;

	if (nla_put_u16(msg, VDPA_ATTR_DEV_MAX_VQ_SIZE, max_vq_size))

		goto msg_err;



	genlmsg_end(msg, hdr);

	return 0;



msg_err:

	genlmsg_cancel(msg, hdr);

	return err;

}



static int vdpa_nl_cmd_dev_get_doit(struct sk_buff *skb, struct genl_info *info)

{

	struct vdpa_device *vdev;

	struct sk_buff *msg;

	const char *devname;

	struct device *dev;

	int err;



	if (!info->attrs[VDPA_ATTR_DEV_NAME])

		return -EINVAL;

	devname = nla_data(info->attrs[VDPA_ATTR_DEV_NAME]);

	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);

	if (!msg)

		return -ENOMEM;



	mutex_lock(&vdpa_dev_mutex);

	dev = bus_find_device(&vdpa_bus, NULL, devname, vdpa_name_match);

	if (!dev) {

		NL_SET_ERR_MSG_MOD(info->extack, "device not found");

		err = -ENODEV;

		goto err;

	}

	vdev = container_of(dev, struct vdpa_device, dev);

	if (!vdev->mdev) {

		err = -EINVAL;

		goto mdev_err;

	}

	err = vdpa_dev_fill(vdev, msg, info->snd_portid, info->snd_seq, 0, info->extack);

	if (!err)

		err = genlmsg_reply(msg, info);

mdev_err:

	put_device(dev);

err:

	mutex_unlock(&vdpa_dev_mutex);

	if (err)

		nlmsg_free(msg);

	return err;

}



struct vdpa_dev_dump_info {

	struct sk_buff *msg;

	struct netlink_callback *cb;

	int start_idx;

	int idx;

};



static int vdpa_dev_dump(struct device *dev, void *data)

{

	struct vdpa_device *vdev = container_of(dev, struct vdpa_device, dev);

	struct vdpa_dev_dump_info *info = data;

	int err;



	if (!vdev->mdev)

		return 0;

	if (info->idx < info->start_idx) {

		info->idx++;

		return 0;

	}

	err = vdpa_dev_fill(vdev, info->msg, NETLINK_CB(info->cb->skb).portid,

			    info->cb->nlh->nlmsg_seq, NLM_F_MULTI, info->cb->extack);

	if (err)

		return err;



	info->idx++;

	return 0;

}



static int vdpa_nl_cmd_dev_get_dumpit(struct sk_buff *msg, struct netlink_callback *cb)

{

	struct vdpa_dev_dump_info info;



	info.msg = msg;

	info.cb = cb;

	info.start_idx = cb->args[0];

	info.idx = 0;



	mutex_lock(&vdpa_dev_mutex);

	bus_for_each_dev(&vdpa_bus, NULL, &info, vdpa_dev_dump);

	mutex_unlock(&vdpa_dev_mutex);

	cb->args[0] = info.idx;

	return msg->len;

}



static const struct nla_policy vdpa_nl_policy[VDPA_ATTR_MAX + 1] = {

	[VDPA_ATTR_MGMTDEV_BUS_NAME] = { .type = NLA_NUL_STRING },

	[VDPA_ATTR_MGMTDEV_DEV_NAME] = { .type = NLA_STRING },
@@ -503,6 +628,12 @@ static const struct genl_ops vdpa_nl_ops[] = { 
		.doit = vdpa_nl_cmd_dev_del_set_doit,

		.flags = GENL_ADMIN_PERM,

	},

	{

		.cmd = VDPA_CMD_DEV_GET,

		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,

		.doit = vdpa_nl_cmd_dev_get_doit,

		.dumpit = vdpa_nl_cmd_dev_get_dumpit,

	},

};



static struct genl_family vdpa_nl_family __ro_after_init = {

include/uapi/linux/vdpa.h

+5 −0
Original line number Diff line number Diff line
@@ -16,6 +16,7 @@ enum vdpa_command { 
	VDPA_CMD_MGMTDEV_GET,		/* can dump */

	VDPA_CMD_DEV_NEW,

	VDPA_CMD_DEV_DEL,

	VDPA_CMD_DEV_GET,		/* can dump */

};



enum vdpa_attr {
@@ -27,6 +28,10 @@ enum vdpa_attr { 
	VDPA_ATTR_MGMTDEV_SUPPORTED_CLASSES,	/* u64 */



	VDPA_ATTR_DEV_NAME,			/* string */

	VDPA_ATTR_DEV_ID,			/* u32 */

	VDPA_ATTR_DEV_VENDOR_ID,		/* u32 */

	VDPA_ATTR_DEV_MAX_VQS,			/* u32 */

	VDPA_ATTR_DEV_MAX_VQ_SIZE,		/* u16 */



	/* new attributes must be added above here */

	VDPA_ATTR_MAX,