btrfs: extent-tree: Add comment for inc_block_group_ro()
authorQu Wenruo <wqu@suse.com>
Fri, 19 Jul 2019 06:51:43 +0000 (14:51 +0800)
committerDavid Sterba <dsterba@suse.com>
Mon, 9 Sep 2019 12:59:00 +0000 (14:59 +0200)
commite91381421f87403f9fd4d3d3b0143fa14d5aa85f
tree212fd763895ec799f72c958166098a01d2965d5e
parent135da9766eea6134229146f6f67fdcbba41120e1
btrfs: extent-tree: Add comment for inc_block_group_ro()

inc_block_group_ro() is only designed to mark one block group read-only,
it doesn't really care if other block groups have enough free space to
contain the used space in the block group.

However due to the close connection between this function and
relocation, sometimes we can be confused and think this function is
responsible for balance space reservation, which is not true.

Add some comment to make the functionality clear.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
fs/btrfs/extent-tree.c