qcow2: Update qcow2_truncate() to support L2 slices

The qcow2_truncate() code is mostly independent from whether
we're using L2 slices or full L2 tables, but in full and
falloc preallocation modes new L2 tables are allocated using
qcow2_alloc_cluster_link_l2().  Therefore the code needs to be
modified to ensure that all nb_clusters that are processed in each
call can be allocated with just one L2 slice.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Message-id: 1fd7d272b5e7b66254a090b74cf2bed1cc334c0e.1517840877.git.berto@igalia.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
This commit is contained in:
Alberto Garcia 2018-02-05 16:33:31 +02:00 committed by Max Reitz
parent 415184f520
commit 13bec229d8

View file

@ -3262,9 +3262,9 @@ static int qcow2_truncate(BlockDriverState *bs, int64_t offset,
host_offset = allocation_start;
guest_offset = old_length;
while (nb_new_data_clusters) {
int64_t guest_cluster = guest_offset >> s->cluster_bits;
int64_t nb_clusters = MIN(nb_new_data_clusters,
s->l2_size - guest_cluster % s->l2_size);
int64_t nb_clusters = MIN(
nb_new_data_clusters,
s->l2_slice_size - offset_to_l2_slice_index(s, guest_offset));
QCowL2Meta allocation = {
.offset = guest_offset,
.alloc_offset = host_offset,