This adds a new superblock field for persisting counters
and adds a sysfs interface in counters/ exposing these counters.
The superblock field is ignored by older versions letting us avoid
an on disk version bump.
Each sysfs file outputs a counter that tracks since filesystem
creation and a counter for the current mount session.
Signed-off-by: Daniel Hill <daniel@gluo.nz>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Initially forked from drivers/md/bcache, bcachefs is a new copy-on-write
filesystem with every feature you could possibly want.
Website: https://bcachefs.org
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
