1 # SPDX-License-Identifier: GPL-2.0-only 1 # SPDX-License-Identifier: GPL-2.0-only
2 config JFFS2_FS 2 config JFFS2_FS
3 tristate "Journalling Flash File Syste 3 tristate "Journalling Flash File System v2 (JFFS2) support"
4 select CRC32 4 select CRC32
5 depends on MTD 5 depends on MTD
6 help 6 help
7 JFFS2 is the second generation of th 7 JFFS2 is the second generation of the Journalling Flash File System
8 for use on diskless embedded devices 8 for use on diskless embedded devices. It provides improved wear
9 levelling, compression and support f 9 levelling, compression and support for hard links. You cannot use
10 this on normal block devices, only o 10 this on normal block devices, only on 'MTD' devices.
11 11
12 Further information on the design an 12 Further information on the design and implementation of JFFS2 is
13 available at <http://sources.redhat. 13 available at <http://sources.redhat.com/jffs2/>.
14 14
15 config JFFS2_FS_DEBUG 15 config JFFS2_FS_DEBUG
16 int "JFFS2 debugging verbosity (0 = qu 16 int "JFFS2 debugging verbosity (0 = quiet, 2 = noisy)"
17 depends on JFFS2_FS 17 depends on JFFS2_FS
18 default "0" 18 default "0"
19 help 19 help
20 This controls the amount of debuggin 20 This controls the amount of debugging messages produced by the JFFS2
21 code. Set it to zero for use in prod 21 code. Set it to zero for use in production systems. For evaluation,
22 testing and debugging, it's advisabl 22 testing and debugging, it's advisable to set it to one. This will
23 enable a few assertions and will pri 23 enable a few assertions and will print debugging messages at the
24 KERN_DEBUG loglevel, where they won' 24 KERN_DEBUG loglevel, where they won't normally be visible. Level 2
25 is unlikely to be useful - it enable 25 is unlikely to be useful - it enables extra debugging in certain
26 areas which at one point needed debu 26 areas which at one point needed debugging, but when the bugs were
27 located and fixed, the detailed mess 27 located and fixed, the detailed messages were relegated to level 2.
28 28
29 If reporting bugs, please try to hav 29 If reporting bugs, please try to have available a full dump of the
30 messages at debug level 1 while the 30 messages at debug level 1 while the misbehaviour was occurring.
31 31
32 config JFFS2_FS_WRITEBUFFER 32 config JFFS2_FS_WRITEBUFFER
33 bool "JFFS2 write-buffering support" 33 bool "JFFS2 write-buffering support"
34 depends on JFFS2_FS 34 depends on JFFS2_FS
35 default y 35 default y
36 help 36 help
37 This enables the write-buffering sup 37 This enables the write-buffering support in JFFS2.
38 38
39 This functionality is required to su 39 This functionality is required to support JFFS2 on the following
40 types of flash devices: 40 types of flash devices:
41 - NAND flash 41 - NAND flash
42 - NOR flash with transparent ECC 42 - NOR flash with transparent ECC
43 - DataFlash 43 - DataFlash
44 44
45 config JFFS2_FS_WBUF_VERIFY 45 config JFFS2_FS_WBUF_VERIFY
46 bool "Verify JFFS2 write-buffer reads" 46 bool "Verify JFFS2 write-buffer reads"
47 depends on JFFS2_FS_WRITEBUFFER 47 depends on JFFS2_FS_WRITEBUFFER
48 default n 48 default n
49 help 49 help
50 This causes JFFS2 to read back every 50 This causes JFFS2 to read back every page written through the
51 write-buffer, and check for errors. 51 write-buffer, and check for errors.
52 52
53 config JFFS2_SUMMARY 53 config JFFS2_SUMMARY
54 bool "JFFS2 summary support" 54 bool "JFFS2 summary support"
55 depends on JFFS2_FS 55 depends on JFFS2_FS
56 default n 56 default n
57 help 57 help
58 This feature makes it possible to us 58 This feature makes it possible to use summary information
59 for faster filesystem mount. 59 for faster filesystem mount.
60 60
61 The summary information can be inser 61 The summary information can be inserted into a filesystem image
62 by the utility 'sumtool'. 62 by the utility 'sumtool'.
63 63
64 If unsure, say 'N'. 64 If unsure, say 'N'.
65 65
66 config JFFS2_FS_XATTR 66 config JFFS2_FS_XATTR
67 bool "JFFS2 XATTR support" 67 bool "JFFS2 XATTR support"
68 depends on JFFS2_FS 68 depends on JFFS2_FS
69 default n 69 default n
70 help 70 help
71 Extended attributes are name:value p 71 Extended attributes are name:value pairs associated with inodes by
72 the kernel or by users (see the attr 72 the kernel or by users (see the attr(5) manual page for details).
73 73
74 If unsure, say N. 74 If unsure, say N.
75 75
76 config JFFS2_FS_POSIX_ACL 76 config JFFS2_FS_POSIX_ACL
77 bool "JFFS2 POSIX Access Control Lists 77 bool "JFFS2 POSIX Access Control Lists"
78 depends on JFFS2_FS_XATTR 78 depends on JFFS2_FS_XATTR
79 default y 79 default y
80 select FS_POSIX_ACL 80 select FS_POSIX_ACL
81 help 81 help
82 Posix Access Control Lists (ACLs) su 82 Posix Access Control Lists (ACLs) support permissions for users and
83 groups beyond the owner/group/world 83 groups beyond the owner/group/world scheme.
84 84
85 If you don't know what Access Contro 85 If you don't know what Access Control Lists are, say N
86 86
87 config JFFS2_FS_SECURITY 87 config JFFS2_FS_SECURITY
88 bool "JFFS2 Security Labels" 88 bool "JFFS2 Security Labels"
89 depends on JFFS2_FS_XATTR 89 depends on JFFS2_FS_XATTR
90 default y 90 default y
91 help 91 help
92 Security labels support alternative 92 Security labels support alternative access control models
93 implemented by security modules like 93 implemented by security modules like SELinux. This option
94 enables an extended attribute handle 94 enables an extended attribute handler for file security
95 labels in the jffs2 filesystem. 95 labels in the jffs2 filesystem.
96 96
97 If you are not using a security modu 97 If you are not using a security module that requires using
98 extended attributes for file securit 98 extended attributes for file security labels, say N.
99 99
100 config JFFS2_COMPRESSION_OPTIONS 100 config JFFS2_COMPRESSION_OPTIONS
101 bool "Advanced compression options for 101 bool "Advanced compression options for JFFS2"
102 depends on JFFS2_FS 102 depends on JFFS2_FS
103 default n 103 default n
104 help 104 help
105 Enabling this option allows you to e 105 Enabling this option allows you to explicitly choose which
106 compression modules, if any, are ena 106 compression modules, if any, are enabled in JFFS2. Removing
107 compressors can mean you cannot read 107 compressors can mean you cannot read existing file systems,
108 and enabling experimental compressor 108 and enabling experimental compressors can mean that you
109 write a file system which cannot be 109 write a file system which cannot be read by a standard kernel.
110 110
111 If unsure, you should _definitely_ s 111 If unsure, you should _definitely_ say 'N'.
112 112
113 config JFFS2_ZLIB 113 config JFFS2_ZLIB
114 bool "JFFS2 ZLIB compression support" 114 bool "JFFS2 ZLIB compression support" if JFFS2_COMPRESSION_OPTIONS
115 select ZLIB_INFLATE 115 select ZLIB_INFLATE
116 select ZLIB_DEFLATE 116 select ZLIB_DEFLATE
117 depends on JFFS2_FS 117 depends on JFFS2_FS
118 default y 118 default y
119 help 119 help
120 Zlib is designed to be a free, gener 120 Zlib is designed to be a free, general-purpose, legally unencumbered,
121 lossless data-compression library fo 121 lossless data-compression library for use on virtually any computer
122 hardware and operating system. See < 122 hardware and operating system. See <http://www.gzip.org/zlib/> for
123 further information. 123 further information.
124 124
125 Say 'Y' if unsure. 125 Say 'Y' if unsure.
126 126
127 config JFFS2_LZO 127 config JFFS2_LZO
128 bool "JFFS2 LZO compression support" i 128 bool "JFFS2 LZO compression support" if JFFS2_COMPRESSION_OPTIONS
129 select LZO_COMPRESS 129 select LZO_COMPRESS
130 select LZO_DECOMPRESS 130 select LZO_DECOMPRESS
131 depends on JFFS2_FS 131 depends on JFFS2_FS
132 default n 132 default n
133 help 133 help
134 minilzo-based compression. Generally 134 minilzo-based compression. Generally works better than Zlib.
135 135
136 This feature was added in July, 2007 136 This feature was added in July, 2007. Say 'N' if you need
137 compatibility with older bootloaders 137 compatibility with older bootloaders or kernels.
138 138
139 config JFFS2_RTIME 139 config JFFS2_RTIME
140 bool "JFFS2 RTIME compression support" 140 bool "JFFS2 RTIME compression support" if JFFS2_COMPRESSION_OPTIONS
141 depends on JFFS2_FS 141 depends on JFFS2_FS
142 default y 142 default y
143 help 143 help
144 Rtime does manage to recompress alre 144 Rtime does manage to recompress already-compressed data. Say 'Y' if unsure.
145 145
146 config JFFS2_RUBIN 146 config JFFS2_RUBIN
147 bool "JFFS2 RUBIN compression support" 147 bool "JFFS2 RUBIN compression support" if JFFS2_COMPRESSION_OPTIONS
148 depends on JFFS2_FS 148 depends on JFFS2_FS
149 default n 149 default n
150 help 150 help
151 RUBINMIPS and DYNRUBIN compressors. 151 RUBINMIPS and DYNRUBIN compressors. Say 'N' if unsure.
152 152
153 choice 153 choice
154 prompt "JFFS2 default compression mode !! 154 prompt "JFFS2 default compression mode" if JFFS2_COMPRESSION_OPTIONS
155 default JFFS2_CMODE_PRIORITY 155 default JFFS2_CMODE_PRIORITY
156 depends on JFFS2_COMPRESSION_OPTIONS <<
157 depends on JFFS2_FS 156 depends on JFFS2_FS
158 help 157 help
159 You can set here the default compres 158 You can set here the default compression mode of JFFS2 from
160 the available compression modes. Don 159 the available compression modes. Don't touch if unsure.
161 160
162 config JFFS2_CMODE_NONE 161 config JFFS2_CMODE_NONE
163 bool "no compression" 162 bool "no compression"
164 help 163 help
165 Uses no compression. 164 Uses no compression.
166 165
167 config JFFS2_CMODE_PRIORITY 166 config JFFS2_CMODE_PRIORITY
168 bool "priority" 167 bool "priority"
169 help 168 help
170 Tries the compressors in a predefine 169 Tries the compressors in a predefined order and chooses the first
171 successful one. 170 successful one.
172 171
173 config JFFS2_CMODE_SIZE 172 config JFFS2_CMODE_SIZE
174 bool "size" 173 bool "size"
175 help 174 help
176 Tries all compressors and chooses th 175 Tries all compressors and chooses the one which has the smallest
177 result. 176 result.
178 177
179 config JFFS2_CMODE_FAVOURLZO 178 config JFFS2_CMODE_FAVOURLZO
180 bool "Favour LZO" 179 bool "Favour LZO"
181 help 180 help
182 Tries all compressors and chooses th 181 Tries all compressors and chooses the one which has the smallest
183 result but gives some preference to 182 result but gives some preference to LZO (which has faster
184 decompression) at the expense of siz 183 decompression) at the expense of size.
185 184
186 endchoice 185 endchoice
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.