xref: /linux/fs/ubifs/Kconfig (revision be709d48329a500621d2a05835283150ae137b45)
1config UBIFS_FS
2	tristate "UBIFS file system support"
3	select CRC16
4	select CRC32
5	select CRYPTO if UBIFS_FS_ADVANCED_COMPR
6	select CRYPTO if UBIFS_FS_LZO
7	select CRYPTO if UBIFS_FS_ZLIB
8	select CRYPTO_LZO if UBIFS_FS_LZO
9	select CRYPTO_DEFLATE if UBIFS_FS_ZLIB
10	select CRYPTO_HASH_INFO
11	select UBIFS_FS_XATTR if FS_ENCRYPTION
12	depends on MTD_UBI
13	help
14	  UBIFS is a file system for flash devices which works on top of UBI.
15
16if UBIFS_FS
17
18config UBIFS_FS_ADVANCED_COMPR
19	bool "Advanced compression options"
20	help
21	  This option allows to explicitly choose which compressions, if any,
22	  are enabled in UBIFS. Removing compressors means inability to read
23	  existing file systems.
24
25	  If unsure, say 'N'.
26
27config UBIFS_FS_LZO
28	bool "LZO compression support" if UBIFS_FS_ADVANCED_COMPR
29	default y
30	help
31	   LZO compressor is generally faster than zlib but compresses worse.
32	   Say 'Y' if unsure.
33
34config UBIFS_FS_ZLIB
35	bool "ZLIB compression support" if UBIFS_FS_ADVANCED_COMPR
36	default y
37	help
38	  Zlib compresses better than LZO but it is slower. Say 'Y' if unsure.
39
40config UBIFS_ATIME_SUPPORT
41	bool "Access time support"
42	default n
43	help
44	  Originally UBIFS did not support atime, because it looked like a bad idea due
45	  increased flash wear. This option adds atime support and it is disabled by default
46	  to preserve the old behavior. If you enable this option, UBIFS starts updating atime,
47	  which means that file-system read operations will cause writes (inode atime
48	  updates). This may affect file-system performance and increase flash device wear,
49	  so be careful. How often atime is updated depends on the selected strategy:
50	  strictatime is the "heavy", relatime is "lighter", etc.
51
52	  If unsure, say 'N'
53
54config UBIFS_FS_XATTR
55	bool "UBIFS XATTR support"
56	default y
57	help
58	  Saying Y here includes support for extended attributes (xattrs).
59	  Xattrs are name:value pairs associated with inodes by
60	  the kernel or by users (see the attr(5) manual page).
61
62	  If unsure, say Y.
63
64config UBIFS_FS_SECURITY
65	bool "UBIFS Security Labels"
66	depends on UBIFS_FS_XATTR
67	default y
68	help
69	  Security labels provide an access control facility to support Linux
70	  Security Models (LSMs) accepted by AppArmor, SELinux, Smack and TOMOYO
71	  Linux. This option enables an extended attribute handler for file
72	  security labels in the ubifs filesystem, so that it requires enabling
73	  the extended attribute support in advance.
74
75	  If you are not using a security module, say N.
76
77config UBIFS_FS_AUTHENTICATION
78	bool "UBIFS authentication support"
79	depends on KEYS
80	select CRYPTO_HMAC
81	help
82	  Enable authentication support for UBIFS. This feature offers protection
83	  against offline changes for both data and metadata of the filesystem.
84	  If you say yes here you should also select a hashing algorithm such as
85	  sha256, these are not selected automatically since there are many
86	  different options.
87
88endif # UBIFS_FS
89