Commit aeef9b47 authored by Jason Wang's avatar Jason Wang Committed by Michael S. Tsirkin
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virtio-ring: maintain next in extra state for packed virtqueue 



This patch moves next from vring_desc_state_packed to
vring_desc_desc_extra_packed. This makes it simpler to let extra state
to be reused by split virtqueue.

Signed-off-by: default avatarJason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210604055350.58753-2-jasowang@redhat.com


Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
parent e3aadf2e

drivers/virtio/virtio_ring.c

+8 −7
Original line number Diff line number Diff line
@@ -74,7 +74,6 @@ struct vring_desc_state_packed { 
	void *data;			/* Data for callback. */

	struct vring_packed_desc *indir_desc; /* Indirect descriptor, if any. */

	u16 num;			/* Descriptor list length. */

	u16 next;			/* The next desc state in a list. */

	u16 last;			/* The last desc state in a list. */

};
@@ -82,6 +81,7 @@ struct vring_desc_extra_packed { 
	dma_addr_t addr;		/* Buffer DMA addr. */

	u32 len;			/* Buffer length. */

	u16 flags;			/* Descriptor flags. */

	u16 next;			/* The next desc state in a list. */

};



struct vring_virtqueue {
@@ -1067,7 +1067,7 @@ static int virtqueue_add_indirect_packed(struct vring_virtqueue *vq, 
				1 << VRING_PACKED_DESC_F_USED;

	}

	vq->packed.next_avail_idx = n;

	vq->free_head = vq->packed.desc_state[id].next;

	vq->free_head = vq->packed.desc_extra[id].next;



	/* Store token and indirect buffer state. */

	vq->packed.desc_state[id].num = 1;
@@ -1175,7 +1175,7 @@ static inline int virtqueue_add_packed(struct virtqueue *_vq, 
					le16_to_cpu(flags);

			}

			prev = curr;

			curr = vq->packed.desc_state[curr].next;

			curr = vq->packed.desc_extra[curr].next;



			if ((unlikely(++i >= vq->packed.vring.num))) {

				i = 0;
@@ -1296,7 +1296,7 @@ static void detach_buf_packed(struct vring_virtqueue *vq, 
	/* Clear data ptr. */

	state->data = NULL;



	vq->packed.desc_state[state->last].next = vq->free_head;

	vq->packed.desc_extra[state->last].next = vq->free_head;

	vq->free_head = id;

	vq->vq.num_free += state->num;
@@ -1305,7 +1305,7 @@ static void detach_buf_packed(struct vring_virtqueue *vq, 
		for (i = 0; i < state->num; i++) {

			vring_unmap_state_packed(vq,

				&vq->packed.desc_extra[curr]);

			curr = vq->packed.desc_state[curr].next;

			curr = vq->packed.desc_extra[curr].next;

		}

	}
@@ -1656,8 +1656,6 @@ static struct virtqueue *vring_create_virtqueue_packed( 


	/* Put everything in free lists. */

	vq->free_head = 0;

	for (i = 0; i < num-1; i++)

		vq->packed.desc_state[i].next = i + 1;



	vq->packed.desc_extra = kmalloc_array(num,

			sizeof(struct vring_desc_extra_packed),
@@ -1668,6 +1666,9 @@ static struct virtqueue *vring_create_virtqueue_packed( 
	memset(vq->packed.desc_extra, 0,

		num * sizeof(struct vring_desc_extra_packed));



	for (i = 0; i < num - 1; i++)

		vq->packed.desc_extra[i].next = i + 1;



	/* No callback?  Tell other side not to bother us. */

	if (!callback) {

		vq->packed.event_flags_shadow = VRING_PACKED_EVENT_FLAG_DISABLE;