git://bbs.cooldavid.org / net-next-2.6.git / blame
| Commit | Line | Data |
|---|---|---|
| 22635ec9 AD |
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 | |
| 4b676d2d | 8 | filesystem for Linux. It uses zlib/lzo compression to compress both |
| 22635ec9 AD |
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 | |
| 4b676d2d | 14 | timestamps. |
| 22635ec9 AD |
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 | ||
| 637d5c9a | 29 | config SQUASHFS_XATTR |
| 01e5b4e4 PL |
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 | ||
| 79cb8ced CJ |
40 | config SQUASHFS_LZO |
| 41 | bool "Include support for LZO compressed file systems" | |
| 42 | depends on SQUASHFS | |
| 4b676d2d | 43 | default n |
| 79cb8ced | 44 | select LZO_DECOMPRESS |
| 4b676d2d PL |
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. | |
| 79cb8ced | 50 | |
| 4b676d2d PL |
51 | LZO is not the standard compression used in Squashfs and so most |
| 52 | file systems will be readable without selecting this option. | |
| 22635ec9 | 53 | |
| 4b676d2d PL |
54 | If unsure, say N. |
| 55 | ||
| 56 | config SQUASHFS_EMBEDDED | |
| 57 | bool "Additional option for memory-constrained systems" | |
| 22635ec9 AD |
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 | ||
| 65 | config 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. |