[PATCH v2] virtio: add VIRTIO_RING_NO_LEGACY

[Matej Genci <matej.genci@nutanix.com>]

Add macro to disable legacy functions vring_init and vring_size.

Signed-off-by: Matej Genci <matej.genci@nutanix.com>
---

V2: Put all legacy APIs inside guards.

---
 include/uapi/linux/virtio_ring.h | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/include/uapi/linux/virtio_ring.h b/include/uapi/linux/virtio_ring.h
index 4c4e24c291a5..efe5a421b4ea 100644
--- a/include/uapi/linux/virtio_ring.h
+++ b/include/uapi/linux/virtio_ring.h
@@ -118,6 +118,8 @@ struct vring_used {
 	struct vring_used_elem ring[];
 };
 
+#ifndef VIRTIO_RING_NO_LEGACY
+
 struct vring {
 	unsigned int num;
 
@@ -128,6 +130,8 @@ struct vring {
 	struct vring_used *used;
 };
 
+#endif /* VIRTIO_RING_NO_LEGACY */
+
 /* Alignment requirements for vring elements.
  * When using pre-virtio 1.0 layout, these fall out naturally.
  */
@@ -135,6 +139,8 @@ struct vring {
 #define VRING_USED_ALIGN_SIZE 4
 #define VRING_DESC_ALIGN_SIZE 16
 
+#ifndef VIRTIO_RING_NO_LEGACY
+
 /* The standard layout for the ring is a continuous chunk of memory which looks
  * like this.  We assume num is a power of 2.
  *
@@ -195,6 +201,8 @@ static inline int vring_need_event(__u16 event_idx, __u16 new_idx, __u16 old)
 	return (__u16)(new_idx - event_idx - 1) < (__u16)(new_idx - old);
 }
 
+#endif /* VIRTIO_RING_NO_LEGACY */
+
 struct vring_packed_desc_event {
 	/* Descriptor Ring Change Event Offset/Wrap Counter. */
 	__le16 off_wrap;
-- 
2.22.0