Btrfs: add and improve comments
This improves the comments at the top of many functions. It didn't
dive into the guts of functions because I was trying to
avoid merging problems with the new allocator and back reference work.
extent-tree.c and volumes.c were both skipped, and there is definitely
more work todo in cleaning and commenting the code.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/ref-cache.h b/fs/btrfs/ref-cache.h
index 6175647..16f3183 100644
--- a/fs/btrfs/ref-cache.h
+++ b/fs/btrfs/ref-cache.h
@@ -19,8 +19,11 @@
#define __REFCACHE__
struct btrfs_extent_info {
+ /* bytenr and num_bytes find the extent in the extent allocation tree */
u64 bytenr;
u64 num_bytes;
+
+ /* objectid and offset find the back reference for the file */
u64 objectid;
u64 offset;
};