xfs: metadata inode directory trees [v5.5 03/10]
This series delivers a new feature -- metadata inode directories. This
is a separate directory tree (rooted in the superblock) that contains
only inodes that contain filesystem metadata. Different metadata
objects can be looked up with regular paths.
Start by creating xfs_imeta{dir,file}* functions to mediate access to
the metadata directory tree. By the end of this mega series, all
existing metadata inodes (rt+quota) will use this directory tree instead
of the superblock.
Next, define the metadir on-disk format, which consists of marking
inodes with a new iflag that says they're metadata. This prevents
bulkstat and friends from ever getting their hands on fs metadata files.
With a bit of luck, this should all go splendidly.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>