1config SQUASHFS 2 tristate "SquashFS 4.0 - Squashed file system support" 3 depends on BLOCK 4 select ZLIB_INFLATE 5 help 6 Saying Y here includes support for SquashFS 4.0 (a Compressed 7 Read-Only File System). Squashfs is a highly compressed read-only 8 filesystem for Linux. It uses zlib/lzo compression to compress both 9 files, inodes and directories. Inodes in the system are very small 10 and all blocks are packed to minimise data overhead. Block sizes 11 greater than 4K are supported up to a maximum of 1 Mbytes (default 12 block size 128K). SquashFS 4.0 supports 64 bit filesystems and files 13 (larger than 4GB), full uid/gid information, hard links and 14 timestamps. 15 16 Squashfs is intended for general read-only filesystem use, for 17 archival use (i.e. in cases where a .tar.gz file may be used), and in 18 embedded systems where low overhead is needed. Further information 19 and tools are available from http://squashfs.sourceforge.net. 20 21 If you want to compile this as a module ( = code which can be 22 inserted in and removed from the running kernel whenever you want), 23 say M here and read <file:Documentation/modules.txt>. The module 24 will be called squashfs. Note that the root file system (the one 25 containing the directory /) cannot be compiled as a module. 26 27 If unsure, say N. 28 29config SQUASHFS_XATTR 30 bool "Squashfs XATTR support" 31 depends on SQUASHFS 32 default n 33 help 34 Saying Y here includes support for extended attributes (xattrs). 35 Xattrs are name:value pairs associated with inodes by 36 the kernel or by users (see the attr(5) manual page). 37 38 If unsure, say N. 39 40config SQUASHFS_LZO 41 bool "Include support for LZO compressed file systems" 42 depends on SQUASHFS 43 default n 44 select LZO_DECOMPRESS 45 help 46 Saying Y here includes support for reading Squashfs file systems 47 compressed with LZO compresssion. LZO compression is mainly 48 aimed at embedded systems with slower CPUs where the overheads 49 of zlib are too high. 50 51 LZO is not the standard compression used in Squashfs and so most 52 file systems will be readable without selecting this option. 53 54 If unsure, say N. 55 56config SQUASHFS_EMBEDDED 57 bool "Additional option for memory-constrained systems" 58 depends on SQUASHFS 59 default n 60 help 61 Saying Y here allows you to specify cache size. 62 63 If unsure, say N. 64 65config SQUASHFS_FRAGMENT_CACHE_SIZE 66 int "Number of fragments cached" if SQUASHFS_EMBEDDED 67 depends on SQUASHFS 68 default "3" 69 help 70 By default SquashFS caches the last 3 fragments read from 71 the filesystem. Increasing this amount may mean SquashFS 72 has to re-read fragments less often from disk, at the expense 73 of extra system memory. Decreasing this amount will mean 74 SquashFS uses less memory at the expense of extra reads from disk. 75 76 Note there must be at least one cached fragment. Anything 77 much more than three will probably not make much difference. 78