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Alexey Dobriyan22635ec2009-01-22 10:57:46 +03001config 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
29config 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
39config 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.