1# SPDX-License-Identifier: GPL-2.0-only
2config NILFS2_FS
3	tristate "NILFS2 file system support"
4	select CRC32
5	select LEGACY_DIRECT_IO
6	help
7	  NILFS2 is a log-structured file system (LFS) supporting continuous
8	  snapshotting.  In addition to versioning capability of the entire
9	  file system, users can even restore files mistakenly overwritten or
10	  destroyed just a few seconds ago.  Since this file system can keep
11	  consistency like conventional LFS, it achieves quick recovery after
12	  system crashes.
13
14	  NILFS2 creates a number of checkpoints every few seconds or per
15	  synchronous write basis (unless there is no change).  Users can
16	  select significant versions among continuously created checkpoints,
17	  and can change them into snapshots which will be preserved for long
18	  periods until they are changed back to checkpoints.  Each
19	  snapshot is mountable as a read-only file system concurrently with
20	  its writable mount, and this feature is convenient for online backup.
21
22	  Some features including atime, extended attributes, and POSIX ACLs,
23	  are not supported yet.
24
25	  To compile this file system support as a module, choose M here: the
26	  module will be called nilfs2.  If unsure, say N.
27