Use extent buffer based infrastructure to re-implement btrfs_readdir().
Along this rework, some small corner cases fixed:
- Subvolume tree mtime
Mtime of a subvolume tree is recorded in its root item, since there is
no INODE_ITEM for it.
This needs extra search from tree root.
- Output the unknown type
If the DIR_ITEM is corrupted, at least don't try to access the memory
out of boundary.
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Marek Behún <marek.behun@nic.cz>
325dd1f642