On Mon, Jun 16, 2025 at 04:25:15PM +0800, Jason Wang wrote:
> Factor out the split indirect descriptor detaching logic in order to
> make it be reused by the in order support.
allow it to be reused
>
> Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
> Signed-off-by: Jason Wang <jasowang@redhat.com>
> ---
> drivers/virtio/virtio_ring.c | 63 ++++++++++++++++++++----------------
> 1 file changed, 35 insertions(+), 28 deletions(-)
>
> diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> index e8e0d1204f52..259380797ec4 100644
> --- a/drivers/virtio/virtio_ring.c
> +++ b/drivers/virtio/virtio_ring.c
> @@ -773,11 +773,42 @@ static bool virtqueue_kick_prepare_split(struct vring_virtqueue *vq)
> return needs_kick;
> }
>
> +static void detach_indirect_split(struct vring_virtqueue *vq,
> + unsigned int head)
> +{
> + struct vring_desc_extra *extra = vq->split.desc_extra;
> + struct vring_desc *indir_desc =
> + vq->split.desc_state[head].indir_desc;
> + unsigned int j;
> + u32 len, num;
> +
> + /* Free the indirect table, if any, now that it's unmapped. */
> + if (!indir_desc)
> + return;
> + len = vq->split.desc_extra[head].len;
> +
> + BUG_ON(!(vq->split.desc_extra[head].flags &
> + VRING_DESC_F_INDIRECT));
> + BUG_ON(len == 0 || len % sizeof(struct vring_desc));
> +
> + num = len / sizeof(struct vring_desc);
> +
> + extra = (struct vring_desc_extra *)&indir_desc[num];
> +
> + if (vq->use_dma_api) {
> + for (j = 0; j < num; j++)
> + vring_unmap_one_split(vq, &extra[j]);
> + }
> +
> + kfree(indir_desc);
> + vq->split.desc_state[head].indir_desc = NULL;
> +}
> +
> static void detach_buf_split(struct vring_virtqueue *vq, unsigned int head,
> void **ctx)
> {
> struct vring_desc_extra *extra;
> - unsigned int i, j;
> + unsigned int i;
> __virtio16 nextflag = cpu_to_virtio16(vq->vq.vdev, VRING_DESC_F_NEXT);
>
> /* Clear data ptr. */
> @@ -801,34 +832,10 @@ static void detach_buf_split(struct vring_virtqueue *vq, unsigned int head,
> /* Plus final descriptor */
> vq->vq.num_free++;
>
> - if (vq->indirect) {
> - struct vring_desc *indir_desc =
> - vq->split.desc_state[head].indir_desc;
> - u32 len, num;
> -
> - /* Free the indirect table, if any, now that it's unmapped. */
> - if (!indir_desc)
> - return;
> - len = vq->split.desc_extra[head].len;
> -
> - BUG_ON(!(vq->split.desc_extra[head].flags &
> - VRING_DESC_F_INDIRECT));
> - BUG_ON(len == 0 || len % sizeof(struct vring_desc));
> -
> - num = len / sizeof(struct vring_desc);
> -
> - extra = (struct vring_desc_extra *)&indir_desc[num];
> -
> - if (vq->use_dma_api) {
> - for (j = 0; j < num; j++)
> - vring_unmap_one_split(vq, &extra[j]);
> - }
> -
> - kfree(indir_desc);
> - vq->split.desc_state[head].indir_desc = NULL;
> - } else if (ctx) {
> + if (vq->indirect)
> + detach_indirect_split(vq, head);
> + else if (ctx)
> *ctx = vq->split.desc_state[head].indir_desc;
> - }
> }
>
> static bool virtqueue_poll_split(const struct vring_virtqueue *vq,
> --
> 2.34.1