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 <xuanzhuo@xxxxxxxxxxxxxxxxx> --- 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
