There is no necessity to search to the end of the bitmap. Limit the search
area as cluster_index + count.
Add cluster_end variable to avoid its calculation in a few places.
Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
---
block/parallels.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/block/parallels.c b/block/parallels.c
index ae524f1820..4470519656 100644
--- a/block/parallels.c
+++ b/block/parallels.c
@@ -182,13 +182,14 @@ int parallels_mark_used(BlockDriverState *bs, unsigned
long *bitmap,
uint32_t bitmap_size, int64_t off, uint32_t count)
{
BDRVParallelsState *s = bs->opaque;
- uint32_t cluster_index = host_cluster_index(s, off);
+ uint32_t cluster_end, cluster_index = host_cluster_index(s, off);
unsigned long next_used;
- if (cluster_index + count > bitmap_size) {
+ cluster_end = cluster_index + count;
+ if (cluster_end > bitmap_size) {
return -E2BIG;
}
- next_used = find_next_bit(bitmap, bitmap_size, cluster_index);
- if (next_used < cluster_index + count) {
+ next_used = find_next_bit(bitmap, cluster_end, cluster_index);
+ if (next_used < cluster_end) {
return -EBUSY;
}
bitmap_set(bitmap, cluster_index, count);