From 9d908689403dec9eddd7e5a6dd8f98cc1e349d9c Mon Sep 17 00:00:00 2001 From: Kevin Wolf Date: Tue, 2 Feb 2010 16:40:27 -0200 Subject: [PATCH 09/14] qcow2: Allow updating no refcounts RH-Author: Kevin Wolf Message-id: <1265128829-26978-10-git-send-email-kwolf@redhat.com> Patchwork-id: 6849 O-Subject: [RHEL-6 KVM PATCH v2 09/11] qcow2: Allow updating no refcounts Bugzilla: 560623 RH-Acked-by: Markus Armbruster RH-Acked-by: Gleb Natapov RH-Acked-by: Juan Quintela Bugzilla: 560623 Upstream commit: 7322afe 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 Signed-off-by: Kevin Wolf --- block/qcow2-refcount.c | 6 +++++- 1 files changed, 5 insertions(+), 1 deletions(-) Signed-off-by: Eduardo Habkost --- block/qcow2-refcount.c | 6 +++++- 1 files changed, 5 insertions(+), 1 deletions(-) diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c index a28acc0..08e6736 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; -- 1.6.3.rc4.29.g8146