qcow2: Allow updating no refcounts

There's absolutely no problem with updating the refcounts of 0 clusters.
At least snapshot code is doing this and would fail once the result of
update_refcount isn't ignored any more.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This commit is contained in:
Kevin Wolf 2010-01-20 15:03:05 +01:00 committed by Anthony Liguori
parent 09508d13f3
commit 7322afe7ea
1 changed files with 5 additions and 1 deletions

View File

@ -284,8 +284,12 @@ static int update_refcount(BlockDriverState *bs,
printf("update_refcount: offset=%" PRId64 " size=%" PRId64 " addend=%d\n",
offset, length, addend);
#endif
if (length <= 0)
if (length < 0) {
return -EINVAL;
} else if (length == 0) {
return 0;
}
start = offset & ~(s->cluster_size - 1);
last = (offset + length - 1) & ~(s->cluster_size - 1);
for(cluster_offset = start; cluster_offset <= last;