Commit 991976f7 authored by Paolo Bonzini's avatar Paolo Bonzini Committed by Michael S. Tsirkin
Browse files

virtio: use VRingMemoryRegionCaches for descriptor ring 



Reviewed-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
parent c611c764

hw/virtio/virtio.c

+12 −14
Original line number Diff line number Diff line
@@ -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;