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Diffstat (limited to 'hw/virtio/virtio.c')
-rw-r--r--hw/virtio/virtio.c108
1 files changed, 85 insertions, 23 deletions
diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index d40711a31d..aa4f38f50a 100644
--- a/hw/virtio/virtio.c
+++ b/hw/virtio/virtio.c
@@ -23,6 +23,7 @@
#include "hw/virtio/virtio-bus.h"
#include "migration/migration.h"
#include "hw/virtio/virtio-access.h"
+#include "sysemu/dma.h"
/*
* The alignment to use between consumer and producer parts of vring.
@@ -92,7 +93,7 @@ struct VirtQueue
uint16_t queue_index;
- int inuse;
+ unsigned int inuse;
uint16_t vector;
VirtIOHandleOutput handle_output;
@@ -121,7 +122,7 @@ void virtio_queue_update_rings(VirtIODevice *vdev, int n)
static void vring_desc_read(VirtIODevice *vdev, VRingDesc *desc,
hwaddr desc_pa, int i)
{
- address_space_read(&address_space_memory, desc_pa + i * sizeof(VRingDesc),
+ address_space_read(vdev->dma_as, desc_pa + i * sizeof(VRingDesc),
MEMTXATTRS_UNSPECIFIED, (void *)desc, sizeof(VRingDesc));
virtio_tswap64s(vdev, &desc->addr);
virtio_tswap32s(vdev, &desc->len);
@@ -163,7 +164,7 @@ static inline void vring_used_write(VirtQueue *vq, VRingUsedElem *uelem,
virtio_tswap32s(vq->vdev, &uelem->id);
virtio_tswap32s(vq->vdev, &uelem->len);
pa = vq->vring.used + offsetof(VRingUsed, ring[i]);
- address_space_write(&address_space_memory, pa, MEMTXATTRS_UNSPECIFIED,
+ address_space_write(vq->vdev->dma_as, pa, MEMTXATTRS_UNSPECIFIED,
(void *)uelem, sizeof(VRingUsedElem));
}
@@ -249,6 +250,7 @@ int virtio_queue_empty(VirtQueue *vq)
static void virtqueue_unmap_sg(VirtQueue *vq, const VirtQueueElement *elem,
unsigned int len)
{
+ AddressSpace *dma_as = vq->vdev->dma_as;
unsigned int offset;
int i;
@@ -256,17 +258,18 @@ static void virtqueue_unmap_sg(VirtQueue *vq, const VirtQueueElement *elem,
for (i = 0; i < elem->in_num; i++) {
size_t size = MIN(len - offset, elem->in_sg[i].iov_len);
- cpu_physical_memory_unmap(elem->in_sg[i].iov_base,
- elem->in_sg[i].iov_len,
- 1, size);
+ dma_memory_unmap(dma_as, elem->in_sg[i].iov_base,
+ elem->in_sg[i].iov_len,
+ DMA_DIRECTION_FROM_DEVICE, size);
offset += size;
}
for (i = 0; i < elem->out_num; i++)
- cpu_physical_memory_unmap(elem->out_sg[i].iov_base,
- elem->out_sg[i].iov_len,
- 0, elem->out_sg[i].iov_len);
+ dma_memory_unmap(dma_as, elem->out_sg[i].iov_base,
+ elem->out_sg[i].iov_len,
+ DMA_DIRECTION_TO_DEVICE,
+ elem->out_sg[i].iov_len);
}
/* virtqueue_detach_element:
@@ -560,7 +563,10 @@ static bool virtqueue_map_desc(VirtIODevice *vdev, unsigned int *p_num_sg,
goto out;
}
- iov[num_sg].iov_base = cpu_physical_memory_map(pa, &len, is_write);
+ iov[num_sg].iov_base = dma_memory_map(vdev->dma_as, pa, &len,
+ is_write ?
+ DMA_DIRECTION_FROM_DEVICE :
+ DMA_DIRECTION_TO_DEVICE);
if (!iov[num_sg].iov_base) {
virtio_error(vdev, "virtio: bogus descriptor or out of resources");
goto out;
@@ -597,9 +603,9 @@ static void virtqueue_undo_map_desc(unsigned int out_num, unsigned int in_num,
}
}
-static void virtqueue_map_iovec(struct iovec *sg, hwaddr *addr,
- unsigned int *num_sg, unsigned int max_size,
- int is_write)
+static void virtqueue_map_iovec(VirtIODevice *vdev, struct iovec *sg,
+ hwaddr *addr, unsigned int *num_sg,
+ unsigned int max_size, int is_write)
{
unsigned int i;
hwaddr len;
@@ -618,7 +624,10 @@ static void virtqueue_map_iovec(struct iovec *sg, hwaddr *addr,
for (i = 0; i < *num_sg; i++) {
len = sg[i].iov_len;
- sg[i].iov_base = cpu_physical_memory_map(addr[i], &len, is_write);
+ sg[i].iov_base = dma_memory_map(vdev->dma_as,
+ addr[i], &len, is_write ?
+ DMA_DIRECTION_FROM_DEVICE :
+ DMA_DIRECTION_TO_DEVICE);
if (!sg[i].iov_base) {
error_report("virtio: error trying to map MMIO memory");
exit(1);
@@ -630,12 +639,15 @@ static void virtqueue_map_iovec(struct iovec *sg, hwaddr *addr,
}
}
-void virtqueue_map(VirtQueueElement *elem)
+void virtqueue_map(VirtIODevice *vdev, VirtQueueElement *elem)
{
- virtqueue_map_iovec(elem->in_sg, elem->in_addr, &elem->in_num,
- VIRTQUEUE_MAX_SIZE, 1);
- virtqueue_map_iovec(elem->out_sg, elem->out_addr, &elem->out_num,
- VIRTQUEUE_MAX_SIZE, 0);
+ virtqueue_map_iovec(vdev, elem->in_sg, elem->in_addr, &elem->in_num,
+ MIN(ARRAY_SIZE(elem->in_sg), ARRAY_SIZE(elem->in_addr)),
+ 1);
+ virtqueue_map_iovec(vdev, elem->out_sg, elem->out_addr, &elem->out_num,
+ MIN(ARRAY_SIZE(elem->out_sg),
+ ARRAY_SIZE(elem->out_addr)),
+ 0);
}
static void *virtqueue_alloc_element(size_t sz, unsigned out_num, unsigned in_num)
@@ -771,6 +783,44 @@ err_undo_map:
return NULL;
}
+/* virtqueue_drop_all:
+ * @vq: The #VirtQueue
+ * Drops all queued buffers and indicates them to the guest
+ * as if they are done. Useful when buffers can not be
+ * processed but must be returned to the guest.
+ */
+unsigned int virtqueue_drop_all(VirtQueue *vq)
+{
+ unsigned int dropped = 0;
+ VirtQueueElement elem = {};
+ VirtIODevice *vdev = vq->vdev;
+ bool fEventIdx = virtio_vdev_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX);
+
+ if (unlikely(vdev->broken)) {
+ return 0;
+ }
+
+ while (!virtio_queue_empty(vq) && vq->inuse < vq->vring.num) {
+ /* works similar to virtqueue_pop but does not map buffers
+ * and does not allocate any memory */
+ smp_rmb();
+ if (!virtqueue_get_head(vq, vq->last_avail_idx, &elem.index)) {
+ break;
+ }
+ vq->inuse++;
+ vq->last_avail_idx++;
+ if (fEventIdx) {
+ vring_set_avail_event(vq, vq->last_avail_idx);
+ }
+ /* immediately push the element, nothing to unmap
+ * as both in_num and out_num are set to 0 */
+ virtqueue_push(vq, &elem, 0);
+ dropped++;
+ }
+
+ return dropped;
+}
+
/* Reading and writing a structure directly to QEMUFile is *awful*, but
* it is what QEMU has always done by mistake. We can change it sooner
* or later by bumping the version number of the affected vm states.
@@ -788,7 +838,7 @@ typedef struct VirtQueueElementOld {
struct iovec out_sg[VIRTQUEUE_MAX_SIZE];
} VirtQueueElementOld;
-void *qemu_get_virtqueue_element(QEMUFile *f, size_t sz)
+void *qemu_get_virtqueue_element(VirtIODevice *vdev, QEMUFile *f, size_t sz)
{
VirtQueueElement *elem;
VirtQueueElementOld data;
@@ -819,7 +869,7 @@ void *qemu_get_virtqueue_element(QEMUFile *f, size_t sz)
elem->out_sg[i].iov_len = data.out_sg[i].iov_len;
}
- virtqueue_map(elem);
+ virtqueue_map(vdev, elem);
return elem;
}
@@ -878,6 +928,11 @@ static int virtio_validate_features(VirtIODevice *vdev)
{
VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev);
+ if (virtio_host_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM) &&
+ !virtio_vdev_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM)) {
+ return -EFAULT;
+ }
+
if (k->validate_features) {
return k->validate_features(vdev);
} else {
@@ -1861,9 +1916,11 @@ int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id)
/*
* Some devices migrate VirtQueueElements that have been popped
* from the avail ring but not yet returned to the used ring.
+ * Since max ring size < UINT16_MAX it's safe to use modulo
+ * UINT16_MAX + 1 subtraction.
*/
- vdev->vq[i].inuse = vdev->vq[i].last_avail_idx -
- vdev->vq[i].used_idx;
+ vdev->vq[i].inuse = (uint16_t)(vdev->vq[i].last_avail_idx -
+ vdev->vq[i].used_idx);
if (vdev->vq[i].inuse > vdev->vq[i].vring.num) {
error_report("VQ %d size 0x%x < last_avail_idx 0x%x - "
"used_idx 0x%x",
@@ -2001,6 +2058,11 @@ void virtio_queue_set_last_avail_idx(VirtIODevice *vdev, int n, uint16_t idx)
vdev->vq[n].shadow_avail_idx = idx;
}
+void virtio_queue_update_used_idx(VirtIODevice *vdev, int n)
+{
+ vdev->vq[n].used_idx = vring_used_idx(&vdev->vq[n]);
+}
+
void virtio_queue_invalidate_signalled_used(VirtIODevice *vdev, int n)
{
vdev->vq[n].signalled_used_valid = false;