[PATCH v13 12/42] virtio_ring: split: extract the logic of vring init

Xuan Zhuo xuanzhuo at linux.alibaba.com
Tue Jul 26 00:21:55 PDT 2022


Separate the logic of initializing vring, and subsequent patches will
call it separately.

This function completes the variable initialization of split vring. It
together with the logic of atatch constitutes the initialization of
vring.

Signed-off-by: Xuan Zhuo <xuanzhuo at linux.alibaba.com>
Acked-by: Jason Wang <jasowang at redhat.com>
---
 drivers/virtio/virtio_ring.c | 31 +++++++++++++++++++++----------
 1 file changed, 21 insertions(+), 10 deletions(-)

diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 6c24b33ea186..ac973887484f 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -948,6 +948,25 @@ static void *virtqueue_detach_unused_buf_split(struct virtqueue *_vq)
 	return NULL;
 }
 
+static void virtqueue_vring_init_split(struct vring_virtqueue_split *vring_split,
+				       struct vring_virtqueue *vq)
+{
+	struct virtio_device *vdev;
+
+	vdev = vq->vq.vdev;
+
+	vring_split->avail_flags_shadow = 0;
+	vring_split->avail_idx_shadow = 0;
+
+	/* No callback?  Tell other side not to bother us. */
+	if (!vq->vq.callback) {
+		vring_split->avail_flags_shadow |= VRING_AVAIL_F_NO_INTERRUPT;
+		if (!vq->event)
+			vring_split->vring.avail->flags = cpu_to_virtio16(vdev,
+					vring_split->avail_flags_shadow);
+	}
+}
+
 static int vring_alloc_state_extra_split(struct vring_virtqueue_split *vring_split)
 {
 	struct vring_desc_state_split *state;
@@ -2299,16 +2318,6 @@ static struct virtqueue *__vring_new_virtqueue(unsigned int index,
 	vq->split.queue_size_in_bytes = 0;
 
 	vq->split.vring = vring_split->vring;
-	vq->split.avail_flags_shadow = 0;
-	vq->split.avail_idx_shadow = 0;
-
-	/* No callback?  Tell other side not to bother us. */
-	if (!callback) {
-		vq->split.avail_flags_shadow |= VRING_AVAIL_F_NO_INTERRUPT;
-		if (!vq->event)
-			vq->split.vring.avail->flags = cpu_to_virtio16(vdev,
-					vq->split.avail_flags_shadow);
-	}
 
 	err = vring_alloc_state_extra_split(vring_split);
 	if (err) {
@@ -2319,6 +2328,8 @@ static struct virtqueue *__vring_new_virtqueue(unsigned int index,
 	vq->split.desc_state = vring_split->desc_state;
 	vq->split.desc_extra = vring_split->desc_extra;
 
+	virtqueue_vring_init_split(vring_split, vq);
+
 	virtqueue_init(vq, vring_split->vring.num);
 
 	spin_lock(&vdev->vqs_list_lock);
-- 
2.31.0




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