netdev - Re: [PATCH vhost v6 08/10] virtio_ring: export premapped to driver by struct virtqueue

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date: Thu, 28 Mar 2024 15:58:08 +0800
From: Jason Wang <jasowang@...hat.com>
To: Xuan Zhuo <xuanzhuo@...ux.alibaba.com>
Cc: virtualization@...ts.linux.dev, "Michael S. Tsirkin" <mst@...hat.com>, 
	"David S. Miller" <davem@...emloft.net>, Eric Dumazet <edumazet@...gle.com>, 
	Jakub Kicinski <kuba@...nel.org>, Paolo Abeni <pabeni@...hat.com>, netdev@...r.kernel.org
Subject: Re: [PATCH vhost v6 08/10] virtio_ring: export premapped to driver by
 struct virtqueue

On Wed, Mar 27, 2024 at 7:14 PM Xuan Zhuo <xuanzhuo@...ux.alibaba.com> wrote:
>
> Export the premapped to drivers, then drivers can check
> the vq premapped mode after the find_vqs().
> Because the find_vqs() just try to enable the vq premapped mode,
> the driver must check that after find_vqs().

What's the reason for this? For example, we never export use_dma_api.

Thanks

>
> Signed-off-by: Xuan Zhuo <xuanzhuo@...ux.alibaba.com>
> ---
>  drivers/virtio/virtio_ring.c | 13 +++++--------
>  include/linux/virtio.h       |  1 +
>  2 files changed, 6 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> index bbdeab3a9648..543204e26c5a 100644
> --- a/drivers/virtio/virtio_ring.c
> +++ b/drivers/virtio/virtio_ring.c
> @@ -177,9 +177,6 @@ struct vring_virtqueue {
>         /* Host publishes avail event idx */
>         bool event;
>
> -       /* Do DMA mapping by driver */
> -       bool premapped;
> -
>         /* Head of free buffer list. */
>         unsigned int free_head;
>         /* Number we've added since last sync. */
> @@ -297,7 +294,7 @@ static bool vring_use_dma_api(const struct virtio_device *vdev)
>
>  static bool vring_need_unmap_buffer(const struct vring_virtqueue *vring)
>  {
> -       return vring->use_dma_api && !vring->premapped;
> +       return vring->use_dma_api && !vring->vq.premapped;
>  }
>
>  size_t virtio_max_dma_size(const struct virtio_device *vdev)
> @@ -369,7 +366,7 @@ static struct device *vring_dma_dev(const struct vring_virtqueue *vq)
>  static int vring_map_one_sg(const struct vring_virtqueue *vq, struct scatterlist *sg,
>                             enum dma_data_direction direction, dma_addr_t *addr)
>  {
> -       if (vq->premapped) {
> +       if (vq->vq.premapped) {
>                 *addr = sg_dma_address(sg);
>                 return 0;
>         }
> @@ -2148,7 +2145,7 @@ static struct virtqueue *vring_create_virtqueue_packed(struct virtio_device *vde
>         vq->packed_ring = true;
>         vq->dma_dev = dma_dev;
>         vq->use_dma_api = vring_use_dma_api(vdev);
> -       vq->premapped = vq->use_dma_api && cfg_vq_get(cfg, vq, premapped);
> +       vq->vq.premapped = vq->use_dma_api && cfg_vq_get(cfg, vq, premapped);
>
>         vq->indirect = virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC) &&
>                 !cfg_vq_get(cfg, vq, ctx);
> @@ -2696,7 +2693,7 @@ static struct virtqueue *__vring_new_virtqueue(struct virtio_device *vdev,
>  #endif
>         vq->dma_dev = tp_cfg->dma_dev;
>         vq->use_dma_api = vring_use_dma_api(vdev);
> -       vq->premapped = vq->use_dma_api && cfg_vq_get(cfg, vq, premapped);
> +       vq->vq.premapped = vq->use_dma_api && cfg_vq_get(cfg, vq, premapped);
>
>         vq->indirect = virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC) &&
>                 !cfg_vq_get(cfg, vq, ctx);
> @@ -2832,7 +2829,7 @@ int virtqueue_set_dma_premapped(struct virtqueue *_vq)
>                 return -EINVAL;
>         }
>
> -       vq->premapped = true;
> +       vq->vq.premapped = true;
>
>         if (vq->packed_ring) {
>                 kfree(vq->packed.desc_dma);
> diff --git a/include/linux/virtio.h b/include/linux/virtio.h
> index b0201747a263..407277d5a16b 100644
> --- a/include/linux/virtio.h
> +++ b/include/linux/virtio.h
> @@ -36,6 +36,7 @@ struct virtqueue {
>         unsigned int num_free;
>         unsigned int num_max;
>         bool reset;
> +       bool premapped;
>         void *priv;
>  };
>
> --
> 2.32.0.3.g01195cf9f
>