Commit 4942e825 authored by Jason Wang's avatar Jason Wang Committed by Michael S. Tsirkin
Browse files

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: default avatarJason Wang <jasowang@redhat.com>
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
parent 9b5e830b

drivers/vhost/vhost.c

+33 −18
Original line number Diff line number Diff line
@@ -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? */