[PATCH v9 07/32] virtio_ring: split: extract the logic of alloc state and extra

Xuan Zhuo
2022-04-06T16:11:33Z

Separate the logic of creating desc_state, desc_extra, and subsequent
patches will call it independently.

Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
---
drivers/virtio/virtio_ring.c | 53 ++++++++++++++++++++++++++----------
1 file changed, 38 insertions(+), 15 deletions(-)

diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 72d5ae063fa0..6de67439cb57 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -198,6 +198,7 @@ struct vring_virtqueue {
#endif
};

+static struct vring_desc_extra *vring_alloc_desc_extra(unsigned int num);

/*
* Helpers.
@@ -915,6 +916,33 @@ static void *virtqueue_detach_unused_buf_split(struct virtqueue *_vq)
return NULL;
}

+static int vring_alloc_state_extra_split(u32 num,
+ struct vring_desc_state_split **desc_state,
+ struct vring_desc_extra **desc_extra)
+{
+ struct vring_desc_state_split *state;
+ struct vring_desc_extra *extra;
+
+ state = kmalloc_array(num, sizeof(struct vring_desc_state_split), GFP_KERNEL);
+ if (!state)
+ goto err_state;
+
+ extra = vring_alloc_desc_extra(num);
+ if (!extra)
+ goto err_extra;
+
+ memset(state, 0, num * sizeof(struct vring_desc_state_split));
+
+ *desc_state = state;
+ *desc_extra = extra;
+ return 0;
+
+err_extra:
+ kfree(state);
+err_state:
+ return -ENOMEM;
+}
+
static void *vring_alloc_queue_split(struct virtio_device *vdev,
dma_addr_t *dma_addr,
u32 *n,
@@ -2196,7 +2224,10 @@ struct virtqueue *__vring_new_virtqueue(unsigned int index,
void (*callback)(struct virtqueue *),
const char *name)
{
+ struct vring_desc_state_split *state;
+ struct vring_desc_extra *extra;
struct vring_virtqueue *vq;
+ int err;

if (virtio_has_feature(vdev, VIRTIO_F_RING_PACKED))
return NULL;
@@ -2246,30 +2277,22 @@ struct virtqueue *__vring_new_virtqueue(unsigned int index,
vq->split.avail_flags_shadow);
}

- vq->split.desc_state = kmalloc_array(vring.num,
- sizeof(struct vring_desc_state_split), GFP_KERNEL);
- if (!vq->split.desc_state)
- goto err_state;
+ err = vring_alloc_state_extra_split(vring.num, &state, &extra);
+ if (err) {
+ kfree(vq);
+ return NULL;
+ }

- vq->split.desc_extra = vring_alloc_desc_extra(vring.num);
- if (!vq->split.desc_extra)
- goto err_extra;
+ vq->split.desc_state = state;
+ vq->split.desc_extra = extra;

/* Put everything in free lists. */
vq->free_head = 0;
- memset(vq->split.desc_state, 0, vring.num *
- sizeof(struct vring_desc_state_split));

spin_lock(&vdev->vqs_list_lock);
list_add_tail(&vq->vq.list, &vdev->vqs);
spin_unlock(&vdev->vqs_list_lock);
return &vq->vq;
-
-err_extra:
- kfree(vq->split.desc_state);
-err_state:
- kfree(vq);
- return NULL;
}
EXPORT_SYMBOL_GPL(__vring_new_virtqueue);

--
2.31.0