Commit cb7de8ee authored by Josef Bacik's avatar Josef Bacik Committed by David Sterba
Browse files

btrfs: add a comment for new_bytenr in backref_cache_node 



Add a comment for this field so we know what it is used for.  Previously
we used it to update the backref cache, so people may mistakenly think
it is useless, but in fact exists to make sure the backref cache makes
sense.

Reviewed-by: default avatarBoris Burkov <boris@bur.io>
Signed-off-by: default avatarJosef Bacik <josef@toxicpanda.com>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent b1d4d5d1

fs/btrfs/backref.h

+6 −0
Original line number Diff line number Diff line
@@ -318,6 +318,12 @@ struct btrfs_backref_node { 
		u64 bytenr;

	}; /* Use rb_simple_node for search/insert */



	/*

	 * This is a sanity check, whenever we COW a block we will update

	 * new_bytenr with it's current location, and we will check this in

	 * various places to validate that the cache makes sense, it shouldn't

	 * be used for anything else.

	 */

	u64 new_bytenr;

	/* Objectid of tree block owner, can be not uptodate */

	u64 owner;