From: Xuan Zhuo <xuanz...@linux.alibaba.com>
As the spec
https://github.com/oasis-tcs/virtio-spec/commit/42f389989823039724f95bbbd243291ab0064f82
Based on the description provided in the above specification, we have
enabled the virtio-net driver to support acquiring some response
information from the device via the CVQ (Control Virtqueue).
Signed-off-by: Xuan Zhuo <xuanz...@linux.alibaba.com>
---
drivers/net/virtio_net.c | 24 +++++++++++++++++-------
1 file changed, 17 insertions(+), 7 deletions(-)
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 7176b956460b..3bc9b1e621db 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -2527,11 +2527,12 @@ static int virtnet_tx_resize(struct virtnet_info *vi,
* supported by the hypervisor, as indicated by feature bits, should
* never fail unless improperly formatted.
*/
-static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
- struct scatterlist *out)
+static bool virtnet_send_command_reply(struct virtnet_info *vi, u8 class, u8
cmd,
+ struct scatterlist *out,
+ struct scatterlist *in)
{
- struct scatterlist *sgs[4], hdr, stat;
- unsigned out_num = 0, tmp;
+ struct scatterlist *sgs[5], hdr, stat;
+ u32 out_num = 0, tmp, in_num = 0;
int ret;
/* Caller should know better */
@@ -2549,10 +2550,13 @@ static bool virtnet_send_command(struct virtnet_info
*vi, u8 class, u8 cmd,
/* Add return status. */
sg_init_one(&stat, &vi->ctrl->status, sizeof(vi->ctrl->status));
- sgs[out_num] = &stat;
+ sgs[out_num + in_num++] = &stat;
- BUG_ON(out_num + 1 > ARRAY_SIZE(sgs));
- ret = virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC);
+ if (in)
+ sgs[out_num + in_num++] = in;
+
+ BUG_ON(out_num + in_num > ARRAY_SIZE(sgs));
+ ret = virtqueue_add_sgs(vi->cvq, sgs, out_num, in_num, vi, GFP_ATOMIC);
if (ret < 0) {
dev_warn(&vi->vdev->dev,
"Failed to add sgs for command vq: %d\n.", ret);
@@ -2574,6 +2578,12 @@ static bool virtnet_send_command(struct virtnet_info
*vi, u8 class, u8 cmd,
return vi->ctrl->status == VIRTIO_NET_OK;
}
+static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
+ struct scatterlist *out)
+{
+ return virtnet_send_command_reply(vi, class, cmd, out, NULL);
+}
+
static int virtnet_set_mac_address(struct net_device *dev, void *p)
{
struct virtnet_info *vi = netdev_priv(dev);
--
2.32.0.3.g01195cf9f
