| Alexey Dobriyan | 22635ec | 2009-01-22 10:57:46 +0300 | [diff] [blame^] | 1 | config 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 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 | |
| 29 | config SQUASHFS_EMBEDDED |
| 30 | |
| 31 | bool "Additional option for memory-constrained systems" |
| 32 | depends on SQUASHFS |
| 33 | default n |
| 34 | help |
| 35 | Saying Y here allows you to specify cache size. |
| 36 | |
| 37 | If unsure, say N. |
| 38 | |
| 39 | config SQUASHFS_FRAGMENT_CACHE_SIZE |
| 40 | int "Number of fragments cached" if SQUASHFS_EMBEDDED |
| 41 | depends on SQUASHFS |
| 42 | default "3" |
| 43 | help |
| 44 | By default SquashFS caches the last 3 fragments read from |
| 45 | the filesystem. Increasing this amount may mean SquashFS |
| 46 | has to re-read fragments less often from disk, at the expense |
| 47 | of extra system memory. Decreasing this amount will mean |
| 48 | SquashFS uses less memory at the expense of extra reads from disk. |
| 49 | |
| 50 | Note there must be at least one cached fragment. Anything |
| 51 | much more than three will probably not make much difference. |