Commit 9dc6b944 authored by Jason Wang's avatar Jason Wang Committed by Michael S. Tsirkin
Browse files

virtio_ring: factor out split indirect detaching logic 



Factor out the split indirect descriptor detaching logic in order to
allow it to be reused by the in order support.

Acked-by: default avatarEugenio Pérez <eperezma@redhat.com>
Reviewed-by: default avatarXuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: default avatarJason Wang <jasowang@redhat.com>
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Message-Id: <20251230064649.55597-18-jasowang@redhat.com>
parent fa56d17b

drivers/virtio/virtio_ring.c

+34 −28
Original line number Diff line number Diff line
@@ -775,11 +775,41 @@ 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_map_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. */
@@ -802,35 +832,11 @@ 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_map_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,

				 unsigned int last_used_idx)