f2fs: expose resizable_tail feature via sysfs

Userspace has no way to know whether the kernel supports the
resizable_tail_secno mount option before mounting. Passing it to a
kernel without the support fails the mount with -EINVAL, and checking
/sys/fs/f2fs/<disk>/pinned_area_max_secno requires an f2fs instance
to be mounted already.

Export /sys/fs/f2fs/features/resizable_tail so that userspace can check
the support before formatting or mounting a filesystem that relies on
resizable_tail_secno, e.g. a filesystem whose tail is going to be shrunk
online later.

Cc: stable@vger.kernel.org
Fixes: c966d29e01bb ("f2fs: support resizable tail section and unify pinned allocation")
Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

0 files changed, 0 insertions, 0 deletions