btrfs: fix integer overflow in calc_reclaim_items_nr
Dave Jones hit a WARN_ON(nr < 0) in btrfs_wait_ordered_roots() with
v4.12-rc6. This was because commit 70e7af244 made it possible for
calc_reclaim_items_nr() to return a negative number. It's not really a
bug in that commit, it just didn't go far enough down the stack to find
all the possible 64->32 bit overflows.
This switches calc_reclaim_items_nr() to return a u64 and changes everyone
that uses the results of that math to u64 as well.
Reported-by: Dave Jones <davej@codemonkey.org.uk>
Fixes: 70e7af2 ("Btrfs: fix delalloc accounting leak caused by u32 overflow")
Signed-off-by: Chris Mason <clm@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index fc9dffa..4ce351e 100644
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -2405,7 +2405,7 @@ static int qgroup_reserve(struct btrfs_root *root, u64 num_bytes, bool enforce)
ret = btrfs_start_delalloc_inodes(root, 0);
if (ret)
return ret;
- btrfs_wait_ordered_extents(root, -1, 0, (u64)-1);
+ btrfs_wait_ordered_extents(root, U64_MAX, 0, (u64)-1);
trans = btrfs_join_transaction(root);
if (IS_ERR(trans))
return PTR_ERR(trans);