@@ -120,9 +120,10 @@ void virtio_queue_update_rings(VirtIODevice *vdev, int n)
}
static void vring_desc_read(VirtIODevice *vdev, VRingDesc *desc,
- uint8_t *desc_ptr, int i)
+ MemoryRegionCache *cache, int i)
{
- memcpy(desc, desc_ptr + i * sizeof(VRingDesc), sizeof(VRingDesc));
+ address_space_read_cached(cache, i * sizeof(VRingDesc),
+ desc, sizeof(VRingDesc));
virtio_tswap64s(vdev, &desc->addr);
virtio_tswap32s(vdev, &desc->len);
virtio_tswap16s(vdev, &desc->flags);
@@ -407,7 +408,7 @@ enum {
};
static int virtqueue_read_next_desc(VirtIODevice *vdev, VRingDesc *desc,
- void *desc_ptr, unsigned int max,
+ MemoryRegionCache *desc_cache, unsigned int max,
unsigned int *next)
{
/* If this descriptor says it doesn't chain, we're done. */
@@ -425,7 +426,7 @@ static int virtqueue_read_next_desc(VirtIODevice *vdev, VRingDesc *desc,
return VIRTQUEUE_READ_DESC_ERROR;
}
- vring_desc_read(vdev, desc, desc_ptr, *next);
+ vring_desc_read(vdev, desc, desc_cache, *next);
return VIRTQUEUE_READ_DESC_MORE;
}
@@ -436,24 +437,25 @@ 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;
- void *vring_desc_ptr;
- void *indirect_desc_ptr = NULL;
- hwaddr len = 0;
+ MemoryRegionCache vring_desc_cache;
+ MemoryRegionCache indirect_desc_cache = MEMORY_REGION_CACHE_INVALID;
+ int64_t len = 0;
int rc;
idx = vq->last_avail_idx;
total_bufs = in_total = out_total = 0;
max = vq->vring.num;
- len = max * sizeof(VRingDesc);
- vring_desc_ptr = address_space_map(vdev->dma_as, vq->vring.desc, &len, false);
+ len = address_space_cache_init(&vring_desc_cache, vdev->dma_as,
+ vq->vring.desc, max * sizeof(VRingDesc),
+ false);
if (len < max * sizeof(VRingDesc)) {
virtio_error(vdev, "Cannot map descriptor ring");
goto err;
}
while ((rc = virtqueue_num_heads(vq, idx)) > 0) {
- void *desc_ptr = vring_desc_ptr;
+ MemoryRegionCache *desc_cache = &vring_desc_cache;
unsigned int num_bufs;
VRingDesc desc;
unsigned int i;
@@ -464,10 +466,9 @@ void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes,
goto err;
}
- vring_desc_read(vdev, &desc, desc_ptr, i);
+ vring_desc_read(vdev, &desc, desc_cache, i);
if (desc.flags & VRING_DESC_F_INDIRECT) {
- len = desc.len;
if (desc.len % sizeof(VRingDesc)) {
virtio_error(vdev, "Invalid size for indirect buffer table");
goto err;
@@ -480,9 +481,10 @@ void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes,
}
/* loop over the indirect descriptor table */
- indirect_desc_ptr = address_space_map(vdev->dma_as, desc.addr,
- &len, false);
- desc_ptr = indirect_desc_ptr;
+ len = address_space_cache_init(&indirect_desc_cache,
+ vdev->dma_as,
+ desc.addr, desc.len, false);
+ desc_cache = &indirect_desc_cache;
if (len < desc.len) {
virtio_error(vdev, "Cannot map indirect buffer");
goto err;
@@ -490,7 +492,7 @@ void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes,
max = desc.len / sizeof(VRingDesc);
num_bufs = i = 0;
- vring_desc_read(vdev, &desc, desc_ptr, i);
+ vring_desc_read(vdev, &desc, desc_cache, i);
}
do {
@@ -509,16 +511,15 @@ void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes,
goto done;
}
- rc = virtqueue_read_next_desc(vdev, &desc, desc_ptr, max, &i);
+ rc = virtqueue_read_next_desc(vdev, &desc, desc_cache, max, &i);
} while (rc == VIRTQUEUE_READ_DESC_MORE);
if (rc == VIRTQUEUE_READ_DESC_ERROR) {
goto err;
}
- if (desc_ptr == indirect_desc_ptr) {
- address_space_unmap(vdev->dma_as, desc_ptr, len, false, 0);
- indirect_desc_ptr = NULL;
+ if (desc_cache == &indirect_desc_cache) {
+ address_space_cache_destroy(&indirect_desc_cache);
total_bufs++;
} else {
total_bufs = num_bufs;
@@ -530,10 +531,8 @@ void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes,
}
done:
- if (indirect_desc_ptr) {
- address_space_unmap(vdev->dma_as, indirect_desc_ptr, len, false, 0);
- }
- address_space_unmap(vdev->dma_as, vring_desc_ptr, len, false, 0);
+ address_space_cache_destroy(&indirect_desc_cache);
+ address_space_cache_destroy(&vring_desc_cache);
if (in_bytes) {
*in_bytes = in_total;
}
@@ -673,10 +672,10 @@ 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;
- void *vring_desc_ptr;
- void *indirect_desc_ptr = NULL;
- void *desc_ptr;
- hwaddr len;
+ MemoryRegionCache vring_desc_cache;
+ MemoryRegionCache indirect_desc_cache = MEMORY_REGION_CACHE_INVALID;
+ MemoryRegionCache *desc_cache;
+ int64_t len;
VirtIODevice *vdev = vq->vdev;
VirtQueueElement *elem = NULL;
unsigned out_num, in_num;
@@ -715,15 +714,16 @@ void *virtqueue_pop(VirtQueue *vq, size_t sz)
i = head;
- len = max * sizeof(VRingDesc);
- vring_desc_ptr = address_space_map(vdev->dma_as, vq->vring.desc, &len, false);
+ len = address_space_cache_init(&vring_desc_cache, vdev->dma_as,
+ vq->vring.desc, max * sizeof(VRingDesc),
+ false);
if (len < max * sizeof(VRingDesc)) {
virtio_error(vdev, "Cannot map descriptor ring");
goto done;
}
- desc_ptr = vring_desc_ptr;
- vring_desc_read(vdev, &desc, desc_ptr, i);
+ desc_cache = &vring_desc_cache;
+ vring_desc_read(vdev, &desc, desc_cache, i);
if (desc.flags & VRING_DESC_F_INDIRECT) {
if (desc.len % sizeof(VRingDesc)) {
virtio_error(vdev, "Invalid size for indirect buffer table");
@@ -731,9 +731,9 @@ void *virtqueue_pop(VirtQueue *vq, size_t sz)
}
/* loop over the indirect descriptor table */
- len = desc.len;
- indirect_desc_ptr = address_space_map(vdev->dma_as, desc.addr, &len, false);
- desc_ptr = indirect_desc_ptr;
+ len = address_space_cache_init(&indirect_desc_cache, vdev->dma_as,
+ desc.addr, desc.len, false);
+ desc_cache = &indirect_desc_cache;
if (len < desc.len) {
virtio_error(vdev, "Cannot map indirect buffer");
goto done;
@@ -741,7 +741,7 @@ void *virtqueue_pop(VirtQueue *vq, size_t sz)
max = desc.len / sizeof(VRingDesc);
i = 0;
- vring_desc_read(vdev, &desc, desc_ptr, i);
+ vring_desc_read(vdev, &desc, desc_cache, i);
}
/* Collect all the descriptors */
@@ -772,7 +772,7 @@ void *virtqueue_pop(VirtQueue *vq, size_t sz)
goto err_undo_map;
}
- rc = virtqueue_read_next_desc(vdev, &desc, desc_ptr, max, &i);
+ rc = virtqueue_read_next_desc(vdev, &desc, desc_cache, max, &i);
} while (rc == VIRTQUEUE_READ_DESC_MORE);
if (rc == VIRTQUEUE_READ_DESC_ERROR) {
@@ -795,10 +795,8 @@ void *virtqueue_pop(VirtQueue *vq, size_t sz)
trace_virtqueue_pop(vq, elem, elem->in_num, elem->out_num);
done:
- if (indirect_desc_ptr) {
- address_space_unmap(vdev->dma_as, indirect_desc_ptr, len, false, 0);
- }
- address_space_unmap(vdev->dma_as, vring_desc_ptr, len, false, 0);
+ address_space_cache_destroy(&indirect_desc_cache);
+ address_space_cache_destroy(&vring_desc_cache);
return elem;
@@ -1426,6 +1426,8 @@ struct MemoryRegionCache {
bool is_write;
};
+#define MEMORY_REGION_CACHE_INVALID ((MemoryRegionCache) { .mr = NULL })
+
/* address_space_cache_init: prepare for repeated access to a physical
* memory region
*