On Fri, May 3, 2024 at 10:25 PM Daniel Jurgens <danielj@xxxxxxxxxx> wrote:
>
> Allocate memory for the data when it's used. Ideally the struct could
> be on the stack, but we can't DMA stack memory. With this change only
> the header and status memory are shared between commands, which will
> allow using a tighter lock than RTNL.
>
> Signed-off-by: Daniel Jurgens <danielj@xxxxxxxxxx>
> Reviewed-by: Jiri Pirko <jiri@xxxxxxxxxx>
> ---
> drivers/net/virtio_net.c | 124 +++++++++++++++++++++++++++------------
> 1 file changed, 85 insertions(+), 39 deletions(-)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 9cf93a8a4446..451879d570a8 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -368,15 +368,6 @@ struct virtio_net_ctrl_rss {
> struct control_buf {
> struct virtio_net_ctrl_hdr hdr;
> virtio_net_ctrl_ack status;
> - struct virtio_net_ctrl_mq mq;
> - u8 promisc;
> - u8 allmulti;
> - __virtio16 vid;
> - __virtio64 offloads;
> - struct virtio_net_ctrl_coal_tx coal_tx;
> - struct virtio_net_ctrl_coal_rx coal_rx;
> - struct virtio_net_ctrl_coal_vq coal_vq;
> - struct virtio_net_stats_capabilities stats_cap;
> };
>
> struct virtnet_info {
> @@ -2828,14 +2819,19 @@ static void virtnet_ack_link_announce(struct virtnet_info *vi)
>
> static int _virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
> {
> + struct virtio_net_ctrl_mq *mq __free(kfree) = NULL;
> struct scatterlist sg;
> struct net_device *dev = vi->dev;
>
> if (!vi->has_cvq || !virtio_has_feature(vi->vdev, VIRTIO_NET_F_MQ))
> return 0;
>
> - vi->ctrl->mq.virtqueue_pairs = cpu_to_virtio16(vi->vdev, queue_pairs);
> - sg_init_one(&sg, &vi->ctrl->mq, sizeof(vi->ctrl->mq));
> + mq = kzalloc(sizeof(*mq), GFP_KERNEL);
> + if (!mq)
> + return -ENOMEM;
> +
> + mq->virtqueue_pairs = cpu_to_virtio16(vi->vdev, queue_pairs);
> + sg_init_one(&sg, mq, sizeof(*mq));
>
> if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ,
> VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET, &sg)) {
> @@ -2864,6 +2860,7 @@ static int virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
>
> static int virtnet_close(struct net_device *dev)
> {
> + u8 *promisc_allmulti __free(kfree) = NULL;
> struct virtnet_info *vi = netdev_priv(dev);
> int i;
>
> @@ -2888,6 +2885,7 @@ static void virtnet_rx_mode_work(struct work_struct *work)
> struct scatterlist sg[2];
> struct virtio_net_ctrl_mac *mac_data;
> struct netdev_hw_addr *ha;
> + u8 *promisc_allmulti;
> int uc_count;
> int mc_count;
> void *buf;
> @@ -2899,22 +2897,27 @@ static void virtnet_rx_mode_work(struct work_struct *work)
>
> rtnl_lock();
>
> - vi->ctrl->promisc = ((dev->flags & IFF_PROMISC) != 0);
> - vi->ctrl->allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
> + promisc_allmulti = kzalloc(sizeof(*promisc_allmulti), GFP_ATOMIC);
> + if (!promisc_allmulti) {
There is a missing rtnl_unlock() here ?
> + dev_warn(&dev->dev, "Failed to set RX mode, no memory.\n");
> + return;
> + }
>
>
