vhost: introduce helpers to get the size of metadata area

To avoid code duplication since it will be used by kernel VA prefetching.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Jason Wang 2019-05-24 04:12:16 -04:00 committed by Michael S. Tsirkin
parent 9b5e830b71
commit 4942e8254d
1 changed files with 33 additions and 18 deletions

View File

@ -428,6 +428,32 @@ bool vhost_exceeds_weight(struct vhost_virtqueue *vq,
}
EXPORT_SYMBOL_GPL(vhost_exceeds_weight);
static size_t vhost_get_avail_size(struct vhost_virtqueue *vq,
unsigned int num)
{
size_t event __maybe_unused =
vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
return sizeof(*vq->avail) +
sizeof(*vq->avail->ring) * num + event;
}
static size_t vhost_get_used_size(struct vhost_virtqueue *vq,
unsigned int num)
{
size_t event __maybe_unused =
vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
return sizeof(*vq->used) +
sizeof(*vq->used->ring) * num + event;
}
static size_t vhost_get_desc_size(struct vhost_virtqueue *vq,
unsigned int num)
{
return sizeof(*vq->desc) * num;
}
void vhost_dev_init(struct vhost_dev *dev,
struct vhost_virtqueue **vqs, int nvqs,
int iov_limit, int weight, int byte_weight)
@ -1275,13 +1301,9 @@ static bool vq_access_ok(struct vhost_virtqueue *vq, unsigned int num,
struct vring_used __user *used)
{
size_t s __maybe_unused = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
return access_ok(desc, num * sizeof *desc) &&
access_ok(avail,
sizeof *avail + num * sizeof *avail->ring + s) &&
access_ok(used,
sizeof *used + num * sizeof *used->ring + s);
return access_ok(desc, vhost_get_desc_size(vq, num)) &&
access_ok(avail, vhost_get_avail_size(vq, num)) &&
access_ok(used, vhost_get_used_size(vq, num));
}
static void vhost_vq_meta_update(struct vhost_virtqueue *vq,
@ -1333,22 +1355,18 @@ static bool iotlb_access_ok(struct vhost_virtqueue *vq,
int vq_meta_prefetch(struct vhost_virtqueue *vq)
{
size_t s = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
unsigned int num = vq->num;
if (!vq->iotlb)
return 1;
return iotlb_access_ok(vq, VHOST_ACCESS_RO, (u64)(uintptr_t)vq->desc,
num * sizeof(*vq->desc), VHOST_ADDR_DESC) &&
vhost_get_desc_size(vq, num), VHOST_ADDR_DESC) &&
iotlb_access_ok(vq, VHOST_ACCESS_RO, (u64)(uintptr_t)vq->avail,
sizeof *vq->avail +
num * sizeof(*vq->avail->ring) + s,
vhost_get_avail_size(vq, num),
VHOST_ADDR_AVAIL) &&
iotlb_access_ok(vq, VHOST_ACCESS_WO, (u64)(uintptr_t)vq->used,
sizeof *vq->used +
num * sizeof(*vq->used->ring) + s,
VHOST_ADDR_USED);
vhost_get_used_size(vq, num), VHOST_ADDR_USED);
}
EXPORT_SYMBOL_GPL(vq_meta_prefetch);
@ -1365,13 +1383,10 @@ EXPORT_SYMBOL_GPL(vhost_log_access_ok);
static bool vq_log_access_ok(struct vhost_virtqueue *vq,
void __user *log_base)
{
size_t s = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
return vq_memory_access_ok(log_base, vq->umem,
vhost_has_feature(vq, VHOST_F_LOG_ALL)) &&
(!vq->log_used || log_access_ok(log_base, vq->log_addr,
sizeof *vq->used +
vq->num * sizeof *vq->used->ring + s));
vhost_get_used_size(vq, vq->num)));
}
/* Can we start vq? */