On 30.12.2013 06:29, Hu Tao wrote:
In case of do preallocating metadata with a large cluster size,
qcow2_alloc_cluster_offset() can allocate nothing and returns
a NULL l2meta. This patch checks for it and link2 l2 with only
valid l2meta.
Signed-off-by: Hu Tao <hu...@cn.fujitsu.com>
---
block/qcow2.c | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)
diff --git a/block/qcow2.c b/block/qcow2.c
index 46860d5..380c240 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -1399,18 +1399,20 @@ static int preallocate(BlockDriverState *bs)
offset = 0;
while (nb_sectors) {
- num = MIN(nb_sectors, INT_MAX >> 9);
+ num = MIN(nb_sectors, INT_MAX >> BDRV_SECTOR_BITS);
Well, if you're already adjusting this here, you could also replace the
other occurrences of 9 and 512 in this function. ;-)
ret = qcow2_alloc_cluster_offset(bs, offset, &num,
&host_offset, &meta);
if (ret < 0) {
return ret;
}
- ret = qcow2_alloc_cluster_link_l2(bs, meta);
- if (ret < 0) {
- qcow2_free_any_clusters(bs, meta->alloc_offset, meta->nb_clusters,
- QCOW2_DISCARD_NEVER);
- return ret;
+ if (meta) {
+ ret = qcow2_alloc_cluster_link_l2(bs, meta);
+ if (ret < 0) {
+ qcow2_free_any_clusters(bs, meta->alloc_offset,
+ meta->nb_clusters,
QCOW2_DISCARD_NEVER);
+ return ret;
+ }
}
/* There are no dependent requests, but we need to remove our request
But this doesn't make this patch wrong, so:
Reviewed-by: Max Reitz <mre...@redhat.com>
