From 7322afe7eaa7211285a38ccfb754a0a52911e394 Mon Sep 17 00:00:00 2001 From: Kevin Wolf Date: Wed, 20 Jan 2010 15:03:05 +0100 Subject: [PATCH] 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 Signed-off-by: Anthony Liguori --- block/qcow2-refcount.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c index a84620ffe2..da7d3f2401 100644 --- a/block/qcow2-refcount.c +++ b/block/qcow2-refcount.c @@ -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;