virtio: Add improved queue allocation API
This leaves vring_new_virtqueue alone for compatbility, but it
adds two new improved APIs:
vring_create_virtqueue: Creates a virtqueue backed by automatically
allocated coherent memory. (Some day it this could be extended to
support non-coherent memory, too, if there ends up being a platform
on which it's worthwhile.)
__vring_new_virtqueue: Creates a virtqueue with a manually-specified
layout. This should allow mic_virtio to work much more cleanly.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
diff --git a/include/linux/virtio.h b/include/linux/virtio.h
index 8f4d4bf..d5eb547 100644
--- a/include/linux/virtio.h
+++ b/include/linux/virtio.h
@@ -75,8 +75,27 @@
bool virtqueue_is_broken(struct virtqueue *vq);
-void *virtqueue_get_avail(struct virtqueue *vq);
-void *virtqueue_get_used(struct virtqueue *vq);
+const struct vring *virtqueue_get_vring(struct virtqueue *vq);
+dma_addr_t virtqueue_get_desc_addr(struct virtqueue *vq);
+dma_addr_t virtqueue_get_avail_addr(struct virtqueue *vq);
+dma_addr_t virtqueue_get_used_addr(struct virtqueue *vq);
+
+/*
+ * Legacy accessors -- in almost all cases, these are the wrong functions
+ * to use.
+ */
+static inline void *virtqueue_get_desc(struct virtqueue *vq)
+{
+ return virtqueue_get_vring(vq)->desc;
+}
+static inline void *virtqueue_get_avail(struct virtqueue *vq)
+{
+ return virtqueue_get_vring(vq)->avail;
+}
+static inline void *virtqueue_get_used(struct virtqueue *vq)
+{
+ return virtqueue_get_vring(vq)->used;
+}
/**
* virtio_device - representation of a device using virtio