Re: [PATCH V4 3/6] vDPA: allow userspace to query features of a vDPA device
From: "Michael S. Tsirkin" <mst@redhat.com>
Date: 2022-08-09 19:24:31
Also in:
virtualization
On Fri, Jul 22, 2022 at 07:53:06PM +0800, Zhu Lingshan wrote:
This commit adds a new vDPA netlink attribution VDPA_ATTR_VDPA_DEV_SUPPORTED_FEATURES. Userspace can query features of vDPA devices through this new attr. Signed-off-by: Zhu Lingshan <redacted>
I think at least some discussion and documentation of this attribute versus VDPA_ATTR_DEV_SUPPORTED_FEATURES is called for. Otherwise how do people know which one to use? We can't send everyone to go read the lkml thread.
quoted hunk ↗ jump to hunk
--- drivers/vdpa/vdpa.c | 13 +++++++++---- include/uapi/linux/vdpa.h | 1 + 2 files changed, 10 insertions(+), 4 deletions(-)diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c index ebf2f363fbe7..9b0e39b2f022 100644 --- a/drivers/vdpa/vdpa.c +++ b/drivers/vdpa/vdpa.c@@ -815,7 +815,7 @@ static int vdpa_dev_net_mq_config_fill(struct vdpa_device *vdev, static int vdpa_dev_net_config_fill(struct vdpa_device *vdev, struct sk_buff *msg) { struct virtio_net_config config = {}; - u64 features; + u64 features_device, features_driver; u16 val_u16; vdpa_get_config_unlocked(vdev, 0, &config, sizeof(config));@@ -832,12 +832,17 @@ static int vdpa_dev_net_config_fill(struct vdpa_device *vdev, struct sk_buff *ms if (nla_put_u16(msg, VDPA_ATTR_DEV_NET_CFG_MTU, val_u16)) return -EMSGSIZE; - features = vdev->config->get_driver_features(vdev); - if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_NEGOTIATED_FEATURES, features, + features_driver = vdev->config->get_driver_features(vdev); + if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_NEGOTIATED_FEATURES, features_driver, + VDPA_ATTR_PAD)) + return -EMSGSIZE; + + features_device = vdev->config->get_device_features(vdev); + if (nla_put_u64_64bit(msg, VDPA_ATTR_VDPA_DEV_SUPPORTED_FEATURES, features_device, VDPA_ATTR_PAD)) return -EMSGSIZE; - return vdpa_dev_net_mq_config_fill(vdev, msg, features, &config); + return vdpa_dev_net_mq_config_fill(vdev, msg, features_driver, &config); } static intdiff --git a/include/uapi/linux/vdpa.h b/include/uapi/linux/vdpa.h index 25c55cab3d7c..39f1c3d7c112 100644 --- a/include/uapi/linux/vdpa.h +++ b/include/uapi/linux/vdpa.h@@ -47,6 +47,7 @@ enum vdpa_attr { VDPA_ATTR_DEV_NEGOTIATED_FEATURES, /* u64 */ VDPA_ATTR_DEV_MGMTDEV_MAX_VQS, /* u32 */ VDPA_ATTR_DEV_SUPPORTED_FEATURES, /* u64 */ + VDPA_ATTR_VDPA_DEV_SUPPORTED_FEATURES, /* u64 */ VDPA_ATTR_DEV_QUEUE_INDEX, /* u32 */ VDPA_ATTR_DEV_VENDOR_ATTR_NAME, /* string */-- 2.31.1