virtio_ring: packed: extract the logic of alloc state and extra

Separate the logic for alloc desc_state and desc_extra, which will
be called separately by subsequent patches.

Use struct vring_packed to pass desc_state, desc_extra.

Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220801063902.129329-20-xuanzhuo@linux.alibaba.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 8209923..533af06 100644 (file)
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -1905,6 +1905,33 @@ err:
        return -ENOMEM;
 }
 
+static int vring_alloc_state_extra_packed(struct vring_virtqueue_packed *vring_packed)
+{
+       struct vring_desc_state_packed *state;
+       struct vring_desc_extra *extra;
+       u32 num = vring_packed->vring.num;
+
+       state = kmalloc_array(num, sizeof(struct vring_desc_state_packed), GFP_KERNEL);
+       if (!state)
+               goto err_desc_state;
+
+       memset(state, 0, num * sizeof(struct vring_desc_state_packed));
+
+       extra = vring_alloc_desc_extra(num);
+       if (!extra)
+               goto err_desc_extra;
+
+       vring_packed->desc_state = state;
+       vring_packed->desc_extra = extra;
+
+       return 0;
+
+err_desc_extra:
+       kfree(state);
+err_desc_state:
+       return -ENOMEM;
+}
+
 static struct virtqueue *vring_create_virtqueue_packed(
        unsigned int index,
        unsigned int num,
@@ -1919,6 +1946,7 @@ static struct virtqueue *vring_create_virtqueue_packed(
 {
        struct vring_virtqueue_packed vring_packed = {};
        struct vring_virtqueue *vq;
+       int err;
 
        if (vring_alloc_queue_packed(&vring_packed, vdev, num))
                goto err_ring;
@@ -1963,21 +1991,15 @@ static struct virtqueue *vring_create_virtqueue_packed(
        vq->packed.event_flags_shadow = 0;
        vq->packed.avail_used_flags = 1 << VRING_PACKED_DESC_F_AVAIL;
 
-       vq->packed.desc_state = kmalloc_array(num,
-                       sizeof(struct vring_desc_state_packed),
-                       GFP_KERNEL);
-       if (!vq->packed.desc_state)
-               goto err_desc_state;
-
-       memset(vq->packed.desc_state, 0,
-               num * sizeof(struct vring_desc_state_packed));
+       err = vring_alloc_state_extra_packed(&vring_packed);
+       if (err)
+               goto err_state_extra;
 
        /* Put everything in free lists. */
        vq->free_head = 0;
 
-       vq->packed.desc_extra = vring_alloc_desc_extra(num);
-       if (!vq->packed.desc_extra)
-               goto err_desc_extra;
+       vq->packed.desc_state = vring_packed.desc_state;
+       vq->packed.desc_extra = vring_packed.desc_extra;
 
        /* No callback?  Tell other side not to bother us. */
        if (!callback) {
@@ -1993,9 +2015,7 @@ static struct virtqueue *vring_create_virtqueue_packed(
        spin_unlock(&vdev->vqs_list_lock);
        return &vq->vq;
 
-err_desc_extra:
-       kfree(vq->packed.desc_state);
-err_desc_state:
+err_state_extra:
        kfree(vq);
 err_vq:
        vring_free_packed(&vring_packed, vdev);