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Alexey Dobriyan31db6e92008-08-29 07:19:50 +04001config JFFS2_FS
2 tristate "Journalling Flash File System v2 (JFFS2) support"
3 select CRC32
4 depends on MTD
5 help
6 JFFS2 is the second generation of the Journalling Flash File System
7 for use on diskless embedded devices. It provides improved wear
8 levelling, compression and support for hard links. You cannot use
9 this on normal block devices, only on 'MTD' devices.
10
11 Further information on the design and implementation of JFFS2 is
12 available at <http://sources.redhat.com/jffs2/>.
13
14config JFFS2_FS_DEBUG
15 int "JFFS2 debugging verbosity (0 = quiet, 2 = noisy)"
16 depends on JFFS2_FS
17 default "0"
18 help
19 This controls the amount of debugging messages produced by the JFFS2
20 code. Set it to zero for use in production systems. For evaluation,
21 testing and debugging, it's advisable to set it to one. This will
22 enable a few assertions and will print debugging messages at the
23 KERN_DEBUG loglevel, where they won't normally be visible. Level 2
24 is unlikely to be useful - it enables extra debugging in certain
25 areas which at one point needed debugging, but when the bugs were
26 located and fixed, the detailed messages were relegated to level 2.
27
28 If reporting bugs, please try to have available a full dump of the
29 messages at debug level 1 while the misbehaviour was occurring.
30
31config JFFS2_FS_WRITEBUFFER
32 bool "JFFS2 write-buffering support"
33 depends on JFFS2_FS
34 default y
35 help
36 This enables the write-buffering support in JFFS2.
37
38 This functionality is required to support JFFS2 on the following
39 types of flash devices:
40 - NAND flash
41 - NOR flash with transparent ECC
42 - DataFlash
43
44config JFFS2_FS_WBUF_VERIFY
45 bool "Verify JFFS2 write-buffer reads"
46 depends on JFFS2_FS_WRITEBUFFER
47 default n
48 help
49 This causes JFFS2 to read back every page written through the
50 write-buffer, and check for errors.
51
52config JFFS2_SUMMARY
53 bool "JFFS2 summary support (EXPERIMENTAL)"
54 depends on JFFS2_FS && EXPERIMENTAL
55 default n
56 help
57 This feature makes it possible to use summary information
58 for faster filesystem mount.
59
60 The summary information can be inserted into a filesystem image
61 by the utility 'sumtool'.
62
63 If unsure, say 'N'.
64
65config JFFS2_FS_XATTR
66 bool "JFFS2 XATTR support (EXPERIMENTAL)"
67 depends on JFFS2_FS && EXPERIMENTAL
68 default n
69 help
70 Extended attributes are name:value pairs associated with inodes by
71 the kernel or by users (see the attr(5) manual page, or visit
72 <http://acl.bestbits.at/> for details).
73
74 If unsure, say N.
75
76config JFFS2_FS_POSIX_ACL
77 bool "JFFS2 POSIX Access Control Lists"
78 depends on JFFS2_FS_XATTR
79 default y
80 select FS_POSIX_ACL
81 help
82 Posix Access Control Lists (ACLs) support permissions for users and
83 groups beyond the owner/group/world scheme.
84
85 To learn more about Access Control Lists, visit the Posix ACLs for
86 Linux website <http://acl.bestbits.at/>.
87
88 If you don't know what Access Control Lists are, say N
89
90config JFFS2_FS_SECURITY
91 bool "JFFS2 Security Labels"
92 depends on JFFS2_FS_XATTR
93 default y
94 help
95 Security labels support alternative access control models
96 implemented by security modules like SELinux. This option
97 enables an extended attribute handler for file security
98 labels in the jffs2 filesystem.
99
100 If you are not using a security module that requires using
101 extended attributes for file security labels, say N.
102
103config JFFS2_COMPRESSION_OPTIONS
104 bool "Advanced compression options for JFFS2"
105 depends on JFFS2_FS
106 default n
107 help
108 Enabling this option allows you to explicitly choose which
109 compression modules, if any, are enabled in JFFS2. Removing
110 compressors can mean you cannot read existing file systems,
111 and enabling experimental compressors can mean that you
112 write a file system which cannot be read by a standard kernel.
113
114 If unsure, you should _definitely_ say 'N'.
115
116config JFFS2_ZLIB
117 bool "JFFS2 ZLIB compression support" if JFFS2_COMPRESSION_OPTIONS
118 select ZLIB_INFLATE
119 select ZLIB_DEFLATE
120 depends on JFFS2_FS
121 default y
122 help
123 Zlib is designed to be a free, general-purpose, legally unencumbered,
124 lossless data-compression library for use on virtually any computer
125 hardware and operating system. See <http://www.gzip.org/zlib/> for
126 further information.
127
128 Say 'Y' if unsure.
129
130config JFFS2_LZO
131 bool "JFFS2 LZO compression support" if JFFS2_COMPRESSION_OPTIONS
132 select LZO_COMPRESS
133 select LZO_DECOMPRESS
134 depends on JFFS2_FS
135 default n
136 help
137 minilzo-based compression. Generally works better than Zlib.
138
139 This feature was added in July, 2007. Say 'N' if you need
140 compatibility with older bootloaders or kernels.
141
142config JFFS2_RTIME
143 bool "JFFS2 RTIME compression support" if JFFS2_COMPRESSION_OPTIONS
144 depends on JFFS2_FS
145 default y
146 help
147 Rtime does manage to recompress already-compressed data. Say 'Y' if unsure.
148
149config JFFS2_RUBIN
150 bool "JFFS2 RUBIN compression support" if JFFS2_COMPRESSION_OPTIONS
151 depends on JFFS2_FS
152 default n
153 help
154 RUBINMIPS and DYNRUBIN compressors. Say 'N' if unsure.
155
156choice
157 prompt "JFFS2 default compression mode" if JFFS2_COMPRESSION_OPTIONS
158 default JFFS2_CMODE_PRIORITY
159 depends on JFFS2_FS
160 help
161 You can set here the default compression mode of JFFS2 from
162 the available compression modes. Don't touch if unsure.
163
164config JFFS2_CMODE_NONE
165 bool "no compression"
166 help
167 Uses no compression.
168
169config JFFS2_CMODE_PRIORITY
170 bool "priority"
171 help
172 Tries the compressors in a predefined order and chooses the first
173 successful one.
174
175config JFFS2_CMODE_SIZE
176 bool "size (EXPERIMENTAL)"
177 help
178 Tries all compressors and chooses the one which has the smallest
179 result.
180
181config JFFS2_CMODE_FAVOURLZO
182 bool "Favour LZO"
183 help
184 Tries all compressors and chooses the one which has the smallest
185 result but gives some preference to LZO (which has faster
186 decompression) at the expense of size.
187
188endchoice