1config 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" 54 depends on JFFS2_FS 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" 67 depends on JFFS2_FS 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" 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 189