virtio_net: Add a lock for the command VQ.

The command VQ will no longer be protected by the RTNL lock. Use a
mutex to protect the control buffer header and the VQ.

Signed-off-by: Daniel Jurgens <danielj@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Heng Qi <hengqi@linux.alibaba.com>
Tested-by: Heng Qi <hengqi@linux.alibaba.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
This commit is contained in:
Daniel Jurgens 2024-05-03 23:24:42 +03:00 committed by Paolo Abeni
parent ff7c7d9f52
commit 6f45ab3e04

View file

@ -411,6 +411,9 @@ struct virtnet_info {
/* Has control virtqueue */
bool has_cvq;
/* Lock to protect the control VQ */
struct mutex cvq_lock;
/* Host can handle any s/g split between our header and packet data */
bool any_header_sg;
@ -2675,6 +2678,7 @@ static bool virtnet_send_command_reply(struct virtnet_info *vi, u8 class, u8 cmd
/* Caller should know better */
BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ));
mutex_lock(&vi->cvq_lock);
vi->ctrl->status = ~0;
vi->ctrl->hdr.class = class;
vi->ctrl->hdr.cmd = cmd;
@ -2697,11 +2701,12 @@ static bool virtnet_send_command_reply(struct virtnet_info *vi, u8 class, u8 cmd
if (ret < 0) {
dev_warn(&vi->vdev->dev,
"Failed to add sgs for command vq: %d\n.", ret);
mutex_unlock(&vi->cvq_lock);
return false;
}
if (unlikely(!virtqueue_kick(vi->cvq)))
return vi->ctrl->status == VIRTIO_NET_OK;
goto unlock;
/* Spin for a response, the kick causes an ioport write, trapping
* into the hypervisor, so the request should be handled immediately.
@ -2712,6 +2717,8 @@ static bool virtnet_send_command_reply(struct virtnet_info *vi, u8 class, u8 cmd
cpu_relax();
}
unlock:
mutex_unlock(&vi->cvq_lock);
return vi->ctrl->status == VIRTIO_NET_OK;
}
@ -5736,6 +5743,8 @@ static int virtnet_probe(struct virtio_device *vdev)
if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
vi->has_cvq = true;
mutex_init(&vi->cvq_lock);
if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) {
mtu = virtio_cread16(vdev,
offsetof(struct virtio_net_config,