[PATCH 15/19] virtio_ring: factor out core logic of buffer detaching

From: Jason Wang
Date: Mon Mar 24 2025 - 02:02:08 EST


Factor out core logic of buffer detaching and leave the id population
to the caller so in order can just call the core logic.

Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
---
drivers/virtio/virtio_ring.c | 17 +++++++++++++----
1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 31aa4a935c27..fe3e6f3d0f96 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -1661,8 +1661,8 @@ static bool virtqueue_kick_prepare_packed(struct vring_virtqueue *vq)
return needs_kick;
}

-static void detach_buf_packed(struct vring_virtqueue *vq,
- unsigned int id, void **ctx)
+static void __detach_buf_packed(struct vring_virtqueue *vq,
+ unsigned int id, void **ctx)
{
struct vring_desc_state_packed *state = NULL;
struct vring_packed_desc *desc;
@@ -1673,8 +1673,6 @@ static void detach_buf_packed(struct vring_virtqueue *vq,
/* Clear data ptr. */
state->data = NULL;

- vq->packed.desc_extra[state->last].next = vq->free_head;
- vq->free_head = id;
vq->vq.num_free += state->num;

if (unlikely(vq->use_dma_api)) {
@@ -1711,6 +1709,17 @@ static void detach_buf_packed(struct vring_virtqueue *vq,
}
}

+static void detach_buf_packed(struct vring_virtqueue *vq,
+ unsigned int id, void **ctx)
+{
+ struct vring_desc_state_packed *state = &vq->packed.desc_state[id];
+
+ vq->packed.desc_extra[state->last].next = vq->free_head;
+ vq->free_head = id;
+
+ return __detach_buf_packed(vq, id, ctx);
+}
+
static inline bool is_used_desc_packed(const struct vring_virtqueue *vq,
u16 idx, bool used_wrap_counter)
{
--
2.42.0