VIRTIO-60: avoid vring and VIRTIO_RING.

These are never introduced, so use simpler names: virtq* for structures
and VIRTIO_ for features.

I added two notes about the old names, for helping people coming from
the old spec.

Signed-off-by: Rusty Russell <rusty@au1.ibm.com>

git-svn-id: https://tools.oasis-open.org/version-control/svn/virtio@327 0c8fb4dd-22a2-4bb5-bc14-6c75a5f43652

1 files changed, 29 insertions, 71 deletions

diff --git a/virtio-ring.h b/virtio-ring.h
index 6d1e2dd..aa01d92 100644
--- a/virtio-ring.h
+++ b/virtio-ring.h
@@ -1,5 +1,5 @@
-#ifndef VIRTIO_RING_H
-#define VIRTIO_RING_H
+#ifndef VIRTQUEUE_H
+#define VIRTQUEUE_H
 /* An interface for efficient virtio implementation.
  *
  * This header is BSD licensed so anyone can use the definitions
@@ -35,33 +35,33 @@
 #include <stdint.h>
 
 /* This marks a buffer as continuing via the next field. */
-#define VRING_DESC_F_NEXT       1
+#define VIRTQ_DESC_F_NEXT       1
 /* This marks a buffer as write-only (otherwise read-only). */
-#define VRING_DESC_F_WRITE      2
+#define VIRTQ_DESC_F_WRITE      2
 /* This means the buffer contains a list of buffer descriptors. */
-#define VRING_DESC_F_INDIRECT   4
+#define VIRTQ_DESC_F_INDIRECT   4
 
 /* The device uses this in used->flags to advise the driver: don't kick me
  * when you add a buffer.  It's unreliable, so it's simply an
  * optimization. */
-#define VRING_USED_F_NO_NOTIFY  1
+#define VIRTQ_USED_F_NO_NOTIFY  1
 /* The driver uses this in avail->flags to advise the device: don't
  * interrupt me when you consume a buffer.  It's unreliable, so it's
  * simply an optimization.  */
-#define VRING_AVAIL_F_NO_INTERRUPT      1
+#define VIRTQ_AVAIL_F_NO_INTERRUPT      1
 
 /* Support for indirect descriptors */
-#define VIRTIO_RING_F_INDIRECT_DESC    28
+#define VIRTIO_F_INDIRECT_DESC    28
 
 /* Support for avail_idx and used_idx fields */
-#define VIRTIO_RING_F_EVENT_IDX        29
+#define VIRTIO_F_EVENT_IDX        29
 
 /* Arbitrary descriptor layouts. */
-#define VIRTIO_F_ANY_LAYOUT            27
+#define VIRTIO_F_ANY_LAYOUT       27
 
-/* Virtio ring descriptors: 16 bytes.
+/* Virtqueue descriptors: 16 bytes.
  * These can chain together via "next". */
-struct vring_desc {
+struct virtq_desc {
         /* Address (guest-physical). */
         le64 addr;
         /* Length. */
@@ -72,93 +72,51 @@ struct vring_desc {
         le16 next;
 };
 
-struct vring_avail {
+struct virtq_avail {
         le16 flags;
         le16 idx;
         le16 ring[];
-        /* Only if VIRTIO_RING_F_EVENT_IDX: le16 used_event; */
+        /* Only if VIRTIO_F_EVENT_IDX: le16 used_event; */
 };
 
 /* le32 is used here for ids for padding reasons. */
-struct vring_used_elem {
+struct virtq_used_elem {
         /* Index of start of used descriptor chain. */
         le32 id;
         /* Total length of the descriptor chain which was written to. */
         le32 len;
 };
 
-struct vring_used {
+struct virtq_used {
         le16 flags;
         le16 idx;
-        struct vring_used_elem ring[];
-        /* Only if VIRTIO_RING_F_EVENT_IDX: le16 avail_event; */
+        struct virtq_used_elem ring[];
+        /* Only if VIRTIO_F_EVENT_IDX: le16 avail_event; */
 };
 
-struct vring {
+struct virtq {
         unsigned int num;
 
-        struct vring_desc *desc;
-        struct vring_avail *avail;
-        struct vring_used *used;
+        struct virtq_desc *desc;
+        struct virtq_avail *avail;
+        struct virtq_used *used;
 };
 
-/* The standard layout for the ring is a continuous chunk of memory which
- * looks like this.  We assume num is a power of 2.
- *
- * struct vring {
- *      // The actual descriptors (16 bytes each)
- *      struct vring_desc desc[num];
- *
- *      // A ring of available descriptor heads with free-running index.
- *      le16 avail_flags;
- *      le16 avail_idx;
- *      le16 available[num];
- *      le16 used_event_idx; // Only if VIRTIO_RING_F_EVENT_IDX
- *
- *      // Padding to the next align boundary.
- *      char pad[];
- *
- *      // A ring of used descriptor heads with free-running index.
- *      le16 used_flags;
- *      le16 used_idx;
- *      struct vring_used_elem used[num];
- *      le16 avail_event_idx; // Only if VIRTIO_RING_F_EVENT_IDX
- * };
- * Note: for virtio PCI, align is 4096.
- */
-static inline void vring_init(struct vring *vr, unsigned int num, void *p,
-                              unsigned long align)
-{
-        vr->num = num;
-        vr->desc = p;
-        vr->avail = p + num*sizeof(struct vring_desc);
-        vr->used = (void *)(((unsigned long)&vr->avail->ring[num] + sizeof(le16)
-                              + align-1)
-                            & ~(align - 1));
-}
-
-static inline unsigned vring_size(unsigned int num, unsigned long align)
-{
-        return ((sizeof(struct vring_desc)*num + sizeof(le16)*(3+num)
-                 + align - 1) & ~(align - 1))
-                + sizeof(le16)*3 + sizeof(struct vring_used_elem)*num;
-}
-
-static inline int vring_need_event(uint16_t event_idx, uint16_t new_idx, uint16_t old_idx)
+static inline int virtq_need_event(uint16_t event_idx, uint16_t new_idx, uint16_t old_idx)
 {
          return (uint16_t)(new_idx - event_idx - 1) < (uint16_t)(new_idx - old_idx);
 }
 
-/* Get location of event indices (only with VIRTIO_RING_F_EVENT_IDX) */
-static inline le16 *vring_used_event(struct vring *vr)
+/* Get location of event indices (only with VIRTIO_F_EVENT_IDX) */
+static inline le16 *virtq_used_event(struct virtq *vq)
 {
         /* For backwards compat, used event index is at *end* of avail ring. */
-        return &vr->avail->ring[vr->num];
+        return &vq->avail->ring[vq->num];
 }
 
-static inline le16 *vring_avail_event(struct vring *vr)
+static inline le16 *virtq_avail_event(struct virtq *vq)
 {
         /* For backwards compat, avail event index is at *end* of used ring. */
-        return (le16 *)&vr->used->ring[vr->num];
+        return (le16 *)&vq->used->ring[vq->num];
 }
-#endif /* VIRTIO_RING_H */
+#endif /* VIRTQUEUE_H */