On 5/4/21 10:20 AM, Vladimir Sementsov-Ogievskiy wrote:
> We'll reuse the function to fix wrong L2 entry bitmap. Support it now.
>
> Signed-off-by: Vladimir Sementsov-Ogievskiy
> ---
> block/qcow2-refcount.c | 18 +++---
> 1 file changed, 15 insertions(+), 3 deletions(-)
>
> diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c
> index f1e771d742..62d59eb2e9 100644
> --- a/block/qcow2-refcount.c
> +++ b/block/qcow2-refcount.c
> @@ -1588,7 +1588,8 @@ enum {
> };
>
> /*
> - * Fix L2 entry by making it QCOW2_CLUSTER_ZERO_PLAIN.
> + * Fix L2 entry by making it QCOW2_CLUSTER_ZERO_PLAIN (or maing all its
> present
making
> + * subclusters QCOW2_SUBCLUSTER_ZERO_PLAIN).
> *
> * Function do res->corruptions-- on success, so caller is responsible to do
> * corresponding res->corruptions++ prior to the call.
> @@ -1605,9 +1606,20 @@ static int fix_l2_entry_by_zero(BlockDriverState *bs,
> BdrvCheckResult *res,
> int idx = l2_index * (l2_entry_size(s) / sizeof(uint64_t));
> uint64_t l2e_offset = l2_offset + (uint64_t)l2_index * l2_entry_size(s);
> int ign = active ? QCOW2_OL_ACTIVE_L2 : QCOW2_OL_INACTIVE_L2;
> -uint64_t l2_entry = has_subclusters(s) ? 0 : QCOW_OFLAG_ZERO;
>
> -set_l2_entry(s, l2_table, l2_index, l2_entry);
> +if (has_subclusters(s)) {
> +uint64_t l2_bitmap = get_l2_bitmap(s, l2_table, l2_index);
> +
> +/* Allocated subclusters becomes zero */
become
> +l2_bitmap |= l2_bitmap << 32;
> +l2_bitmap &= QCOW_L2_BITMAP_ALL_ZEROES;
> +
> +set_l2_bitmap(s, l2_table, l2_index, l2_bitmap);
> +set_l2_entry(s, l2_table, l2_index, 0);
> +} else {
> +set_l2_entry(s, l2_table, l2_index, QCOW_OFLAG_ZERO);
> +}
> +
> ret = qcow2_pre_write_overlap_check(bs, ign, l2e_offset,
> l2_entry_size(s),
> false);
> if (metadata_overlap) {
>
Reviewed-by: Eric Blake
--
Eric Blake, Principal Software Engineer
Red Hat, Inc. +1-919-301-3226
Virtualization: qemu.org | libvirt.org
