Btrfs: make sure a bitmap has enough bytes

We have only been checking for min_bytes available in bitmap entries, but we
won't successfully setup a bitmap cluster unless it has at least bytes in the
bitmap, so in the common case min_bytes is 4k and we want something like 2MB, so
if there are a bunch of bitmap entries with less than 2mb's in them, we'll
search all them anyway, which is suboptimal.  Fix this check.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This commit is contained in:
Josef Bacik 2012-01-26 15:01:11 -05:00 committed by Chris Mason
parent b1375d64c5
commit 357b9784b7

View file

@ -2475,7 +2475,7 @@ setup_cluster_bitmap(struct btrfs_block_group_cache *block_group,
} }
list_for_each_entry(entry, bitmaps, list) { list_for_each_entry(entry, bitmaps, list) {
if (entry->bytes < min_bytes) if (entry->bytes < bytes)
continue; continue;
ret = btrfs_bitmap_cluster(block_group, entry, cluster, offset, ret = btrfs_bitmap_cluster(block_group, entry, cluster, offset,
bytes, cont1_bytes, min_bytes); bytes, cont1_bytes, min_bytes);