xref: /openbmc/linux/fs/ext4/Kconfig (revision 0601f25d)
1# SPDX-License-Identifier: GPL-2.0-only
2# Ext3 configs are here for backward compatibility with old configs which may
3# have EXT3_FS set but not EXT4_FS set and thus would result in non-bootable
4# kernels after the removal of ext3 driver.
5config EXT3_FS
6	tristate "The Extended 3 (ext3) filesystem"
7	select EXT4_FS
8	help
9	  This config option is here only for backward compatibility. ext3
10	  filesystem is now handled by the ext4 driver.
11
12config EXT3_FS_POSIX_ACL
13	bool "Ext3 POSIX Access Control Lists"
14	depends on EXT3_FS
15	select EXT4_FS_POSIX_ACL
16	select FS_POSIX_ACL
17	help
18	  This config option is here only for backward compatibility. ext3
19	  filesystem is now handled by the ext4 driver.
20
21config EXT3_FS_SECURITY
22	bool "Ext3 Security Labels"
23	depends on EXT3_FS
24	select EXT4_FS_SECURITY
25	help
26	  This config option is here only for backward compatibility. ext3
27	  filesystem is now handled by the ext4 driver.
28
29config EXT4_FS
30	tristate "The Extended 4 (ext4) filesystem"
31	select JBD2
32	select CRC16
33	select CRYPTO
34	select CRYPTO_CRC32C
35	select FS_IOMAP
36	select FS_ENCRYPTION_ALGS if FS_ENCRYPTION
37	help
38	  This is the next generation of the ext3 filesystem.
39
40	  Unlike the change from ext2 filesystem to ext3 filesystem,
41	  the on-disk format of ext4 is not forwards compatible with
42	  ext3; it is based on extent maps and it supports 48-bit
43	  physical block numbers.  The ext4 filesystem also supports delayed
44	  allocation, persistent preallocation, high resolution time stamps,
45	  and a number of other features to improve performance and speed
46	  up fsck time.  For more information, please see the web pages at
47	  http://ext4.wiki.kernel.org.
48
49	  The ext4 filesystem supports mounting an ext3 filesystem; while there
50	  are some performance gains from the delayed allocation and inode
51	  table readahead, the best performance gains require enabling ext4
52	  features in the filesystem using tune2fs, or formatting a new
53	  filesystem as an ext4 filesystem initially. Without explicit enabling
54	  of ext4 features, the on disk filesystem format stays fully backward
55	  compatible.
56
57	  To compile this file system support as a module, choose M here. The
58	  module will be called ext4.
59
60	  If unsure, say N.
61
62config EXT4_USE_FOR_EXT2
63	bool "Use ext4 for ext2 file systems"
64	depends on EXT4_FS
65	depends on EXT2_FS=n
66	default y
67	help
68	  Allow the ext4 file system driver code to be used for ext2
69	  file system mounts.  This allows users to reduce their
70	  compiled kernel size by using one file system driver for
71	  ext2, ext3, and ext4 file systems.
72
73config EXT4_FS_POSIX_ACL
74	bool "Ext4 POSIX Access Control Lists"
75	depends on EXT4_FS
76	select FS_POSIX_ACL
77	help
78	  POSIX Access Control Lists (ACLs) support permissions for users and
79	  groups beyond the owner/group/world scheme.
80
81	  If you don't know what Access Control Lists are, say N
82
83config EXT4_FS_SECURITY
84	bool "Ext4 Security Labels"
85	depends on EXT4_FS
86	help
87	  Security labels support alternative access control models
88	  implemented by security modules like SELinux.  This option
89	  enables an extended attribute handler for file security
90	  labels in the ext4 filesystem.
91
92	  If you are not using a security module that requires using
93	  extended attributes for file security labels, say N.
94
95config EXT4_DEBUG
96	bool "Ext4 debugging support"
97	depends on EXT4_FS
98	help
99	  Enables run-time debugging support for the ext4 filesystem.
100
101	  If you select Y here, then you will be able to turn on debugging
102	  using dynamic debug control for mb_debug() / ext_debug() msgs.
103
104config EXT4_KUNIT_TESTS
105	tristate "KUnit tests for ext4" if !KUNIT_ALL_TESTS
106	depends on EXT4_FS && KUNIT
107	default KUNIT_ALL_TESTS
108	help
109	  This builds the ext4 KUnit tests.
110
111	  KUnit tests run during boot and output the results to the debug log
112	  in TAP format (https://testanything.org/). Only useful for kernel devs
113	  running KUnit test harness and are not for inclusion into a production
114	  build.
115
116	  For more information on KUnit and unit tests in general please refer
117	  to the KUnit documentation in Documentation/dev-tools/kunit/.
118
119	  If unsure, say N.
120