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virtio: use VRingMemoryRegionCaches for descriptor ring

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Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Paolo Bonzini 2017-01-27 16:40:18 +01:00 committed by Michael S. Tsirkin
parent c611c76417
commit 991976f751
1 changed files with 12 additions and 14 deletions
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26
hw/virtio/virtio.c
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@ -491,25 +491,24 @@ void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes,
VirtIODevice *vdev = vq->vdev;
unsigned int max, idx;
unsigned int total_bufs, in_total, out_total;
MemoryRegionCache vring_desc_cache;
VRingMemoryRegionCaches *caches;
MemoryRegionCache indirect_desc_cache = MEMORY_REGION_CACHE_INVALID;
int64_t len = 0;
int rc;
rcu_read_lock();
idx = vq->last_avail_idx;
total_bufs = in_total = out_total = 0;
max = vq->vring.num;
len = address_space_cache_init(&vring_desc_cache, vdev->dma_as,
vq->vring.desc, max * sizeof(VRingDesc),
false);
if (len < max * sizeof(VRingDesc)) {
caches = atomic_rcu_read(&vq->vring.caches);
if (caches->desc.len < max * sizeof(VRingDesc)) {
virtio_error(vdev, "Cannot map descriptor ring");
goto err;
}
while ((rc = virtqueue_num_heads(vq, idx)) > 0) {
MemoryRegionCache *desc_cache = &vring_desc_cache;
MemoryRegionCache *desc_cache = &caches->desc;
unsigned int num_bufs;
VRingDesc desc;
unsigned int i;
@ -586,13 +585,13 @@ void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes,
done:
address_space_cache_destroy(&indirect_desc_cache);
address_space_cache_destroy(&vring_desc_cache);
if (in_bytes) {
*in_bytes = in_total;
}
if (out_bytes) {
*out_bytes = out_total;
}
rcu_read_unlock();
return;
err:
@ -726,7 +725,7 @@ static void *virtqueue_alloc_element(size_t sz, unsigned out_num, unsigned in_nu
void *virtqueue_pop(VirtQueue *vq, size_t sz)
{
unsigned int i, head, max;
MemoryRegionCache vring_desc_cache;
VRingMemoryRegionCaches *caches;
MemoryRegionCache indirect_desc_cache = MEMORY_REGION_CACHE_INVALID;
MemoryRegionCache *desc_cache;
int64_t len;
@ -768,15 +767,14 @@ void *virtqueue_pop(VirtQueue *vq, size_t sz)
i = head;
len = address_space_cache_init(&vring_desc_cache, vdev->dma_as,
vq->vring.desc, max * sizeof(VRingDesc),
false);
if (len < max * sizeof(VRingDesc)) {
rcu_read_lock();
caches = atomic_rcu_read(&vq->vring.caches);
if (caches->desc.len < max * sizeof(VRingDesc)) {
virtio_error(vdev, "Cannot map descriptor ring");
goto done;
}
desc_cache = &vring_desc_cache;
desc_cache = &caches->desc;
vring_desc_read(vdev, &desc, desc_cache, i);
if (desc.flags & VRING_DESC_F_INDIRECT) {
if (desc.len % sizeof(VRingDesc)) {
@ -850,7 +848,7 @@ void *virtqueue_pop(VirtQueue *vq, size_t sz)
trace_virtqueue_pop(vq, elem, elem->in_num, elem->out_num);
done:
address_space_cache_destroy(&indirect_desc_cache);
address_space_cache_destroy(&vring_desc_cache);
rcu_read_unlock();
return elem;