diff mbox series

[v10,23/41] virtio_ring: packed: introduce virtqueue_resize_packed()

Message ID 20220624025621.128843-24-xuanzhuo@linux.alibaba.com (mailing list archive)
State Superseded
Headers show
Series virtio pci support VIRTIO_F_RING_RESET | expand

Checks

Context Check Description
netdev/tree_selection success Guessed tree name to be net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count fail Series longer than 15 patches (and no cover letter)
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 4 this patch: 4
netdev/cc_maintainers warning 5 maintainers not CCed: songliubraving@fb.com yhs@fb.com kafai@fb.com andrii@kernel.org kpsingh@kernel.org
netdev/build_clang success Errors and warnings before: 9 this patch: 9
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 4 this patch: 4
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 35 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Xuan Zhuo June 24, 2022, 2:56 a.m. UTC
virtio ring packed supports resize.

Only after the new vring is successfully allocated based on the new num,
we will release the old vring. In any case, an error is returned,
indicating that the vring still points to the old vring.

In the case of an error, re-initialize(by virtqueue_reinit_packed()) the
virtqueue to ensure that the vring can be used.

Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
---
 drivers/virtio/virtio_ring.c | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)
diff mbox series

Patch

diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 740b17550df5..d3b2139200fa 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -2016,6 +2016,35 @@  static struct virtqueue *vring_create_virtqueue_packed(
 	return NULL;
 }
 
+static int virtqueue_resize_packed(struct virtqueue *_vq, u32 num)
+{
+	struct vring_virtqueue_packed vring = {};
+	struct vring_virtqueue *vq = to_vvq(_vq);
+	struct virtio_device *vdev = _vq->vdev;
+	int err;
+
+	if (vring_alloc_queue_packed(&vring, vdev, num))
+		goto err_ring;
+
+	err = vring_alloc_state_extra_packed(&vring);
+	if (err)
+		goto err_state_extra;
+
+	vring_free(&vq->vq);
+
+	virtqueue_init(vq, vring.vring.num);
+	virtqueue_vring_attach_packed(vq, &vring);
+	virtqueue_vring_init_packed(vq);
+
+	return 0;
+
+err_state_extra:
+	vring_free_packed(&vring, vdev);
+err_ring:
+	virtqueue_reinit_packed(vq);
+	return -ENOMEM;
+}
+
 
 /*
  * Generic functions and exported symbols.