Re: [Qemu-devel] [RFC 09/24] qed: add qed_bdrv_get_mapping()

[Stefan Hajnoczi]

On Fri, Jul 29, 2011 at 12:49:39AM -0400, Devin Nakamura wrote:
> +static int bdrv_qed_get_mapping(BlockDriverState *bs, uint64_t *guest_offset,
> +                                uint64_t *host_offset,
> +                                uint64_t *contiguous_bytes)
> +{
> +    BDRVQEDState *s = bs->opaque;
> +    size_t l2_size = s->header.cluster_size * s->table_nelems;
> +    uint64_t pos = *guest_offset + *contiguous_bytes;
> +    uint64_t offset = pos;
> +    size_t len = 0;
> +    QEDRequest req = {.l2_table = NULL};
> +    int ret;
> +
> +    if (pos >= s->header.image_size) {
> +        *contiguous_bytes = 0;
> +        return 0;
> +    }
> +
> +    do {
> +        pos += len;
> +        ret = qed_find_cluster_sync(s, &req, pos, l2_size, &offset, &len);
> +    } while (ret != QED_CLUSTER_FOUND && pos < s->header.image_size);

qed_unref_l2_cache_entry(request.l2_table);

Stefan