From a105bb88f46b60de2adf1ee98745bd59362b09ab Mon Sep 17 00:00:00 2001 From: Ilya Dryomov Date: Mon, 21 Jan 2013 15:15:56 +0200 Subject: [PATCH] Btrfs: fix a regression in balance usage filter Commit 3fed40cc ("Btrfs: cleanup duplicated division functions"), which was merged into 3.8-rc1, has introduced a regression by removing logic that was guarding us against bad user input. Bring it back. Signed-off-by: Ilya Dryomov Signed-off-by: Chris Mason --- fs/btrfs/volumes.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 9c84dbe64f18..469609838913 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -2614,7 +2614,14 @@ static int chunk_usage_filter(struct btrfs_fs_info *fs_info, u64 chunk_offset, cache = btrfs_lookup_block_group(fs_info, chunk_offset); chunk_used = btrfs_block_group_used(&cache->item); - user_thresh = div_factor_fine(cache->key.offset, bargs->usage); + if (bargs->usage == 0) + user_thresh = 0; + else if (bargs->usage > 100) + user_thresh = cache->key.offset; + else + user_thresh = div_factor_fine(cache->key.offset, + bargs->usage); + if (chunk_used < user_thresh) ret = 0;