From: Wei Xu <w...@redhat.com>
Signed-off-by: Wei Xu <w...@redhat.com>
Signed-off-by: Wei Xu <w...@redhat.com>
---
hw/virtio/virtio.c | 109 ++++++++++++++++++++++++++++++++++++++++++++++-------
1 file changed, 96 insertions(+), 13 deletions(-)
diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index 0160d03..6f2da83 100644
--- a/hw/virtio/virtio.c
+++ b/hw/virtio/virtio.c
@@ -371,6 +371,21 @@ static void vring_packed_desc_read(VirtIODevice *vdev,
VRingDescPacked *desc,
virtio_tswap16s(vdev, &desc->flags);
}
+static void vring_packed_desc_write(VirtIODevice *vdev, VRingDescPacked *desc,
+ MemoryRegionCache *cache, int i)
+{
+ virtio_tswap64s(vdev, &desc->addr);
+ virtio_tswap32s(vdev, &desc->len);
+ virtio_tswap16s(vdev, &desc->id);
+ virtio_tswap16s(vdev, &desc->flags);
+ address_space_write_cached(cache,
+ sizeof(VRingDescPacked) * i, desc,
+ sizeof(VRingDescPacked));
+ address_space_cache_invalidate(cache,
+ sizeof(VRingDescPacked) * i,
+ sizeof(VRingDescPacked));
+}
+
static inline bool is_desc_avail(struct VRingDescPacked *desc)
{
return !!(desc->flags & AVAIL_DESC_PACKED(1)) !=
@@ -526,19 +541,11 @@ bool virtqueue_rewind(VirtQueue *vq, unsigned int num)
}
/* Called within rcu_read_lock(). */
-void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem,
+static void virtqueue_split_fill(VirtQueue *vq, const VirtQueueElement *elem,
unsigned int len, unsigned int idx)
{
VRingUsedElem uelem;
- trace_virtqueue_fill(vq, elem, len, idx);
-
- virtqueue_unmap_sg(vq, elem, len);
-
- if (unlikely(vq->vdev->broken)) {
- return;
- }
-
if (unlikely(!vq->vring.used)) {
return;
}
@@ -550,16 +557,64 @@ void virtqueue_fill(VirtQueue *vq, const VirtQueueElement
*elem,
vring_used_write(vq, &uelem, idx);
}
-/* Called within rcu_read_lock(). */
-void virtqueue_flush(VirtQueue *vq, unsigned int count)
+static void virtqueue_packed_fill(VirtQueue *vq, const VirtQueueElement *elem,
+ unsigned int len, unsigned int idx)
{
- uint16_t old, new;
+ uint16_t w, head;
+ VRingMemoryRegionCaches *caches;
+ VRingDescPacked desc = {
+ .addr = 0,
+ .flags = 0,
+ };
+
+ if (unlikely(!vq->vring.desc)) {
+ return;
+ }
+
+ caches = vring_get_region_caches(vq);
+ head = vq->used_idx + idx;
+ head = head >= vq->vring.num ? (head - vq->vring.num) : head;
+ vring_packed_desc_read(vq->vdev, &desc, &caches->desc, head);
+
+ w = (desc.flags & AVAIL_DESC_PACKED(1)) >> 7;
+ desc.flags &= ~(AVAIL_DESC_PACKED(1) | USED_DESC_PACKED(1));
+ desc.flags |= AVAIL_DESC_PACKED(w) | USED_DESC_PACKED(w);
+ if (!(desc.flags & VRING_DESC_F_INDIRECT)) {
+ if (!(desc.flags & VRING_DESC_F_WRITE)) {
+ desc.len = 0;
+ } else {
+ desc.len = len;
+ }
+ }
+ vring_packed_desc_write(vq->vdev, &desc, &caches->desc, head);
+
+ /* Make sure flags has been updated */
+ smp_mb();
+}
+
+void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem,
+ unsigned int len, unsigned int idx)
+{
+ trace_virtqueue_fill(vq, elem, len, idx);
+
+ virtqueue_unmap_sg(vq, elem, len);
if (unlikely(vq->vdev->broken)) {
- vq->inuse -= count;
return;
}
+ if (virtio_vdev_has_feature(vq->vdev, VIRTIO_F_RING_PACKED)) {
+ virtqueue_packed_fill(vq, elem, len, idx);
+ } else {
+ virtqueue_split_fill(vq, elem, len, idx);
+ }
+}
+
+/* Called within rcu_read_lock(). */
+static void virtqueue_split_flush(VirtQueue *vq, unsigned int count)
+{
+ uint16_t old, new;
+
if (unlikely(!vq->vring.used)) {
return;
}
@@ -575,6 +630,34 @@ void virtqueue_flush(VirtQueue *vq, unsigned int count)
vq->signalled_used_valid = false;
}
+static void virtqueue_packed_flush(VirtQueue *vq, unsigned int count)
+{
+ if (unlikely(!vq->vring.desc)) {
+ return;
+ }
+
+ vq->inuse -= count;
+ vq->used_idx += count;
+ if (vq->used_idx >= vq->vring.num) {
+ vq->used_idx -= vq->vring.num;
+ vq->used_wrap_counter = !vq->used_wrap_counter;
+ }
+}
+
+void virtqueue_flush(VirtQueue *vq, unsigned int count)
+{
+ if (unlikely(vq->vdev->broken)) {
+ vq->inuse -= count;
+ return;
+ }
+
+ if (virtio_vdev_has_feature(vq->vdev, VIRTIO_F_RING_PACKED)) {
+ virtqueue_packed_flush(vq, count);
+ } else {
+ virtqueue_split_flush(vq, count);
+ }
+}
+
void virtqueue_push(VirtQueue *vq, const VirtQueueElement *elem,
unsigned int len)
{
--
1.8.3.1
