| config SQUASHFS | |
| tristate "SquashFS 4.0 - Squashed file system support" | |
| depends on BLOCK | |
| select ZLIB_INFLATE | |
| help | |
| Saying Y here includes support for SquashFS 4.0 (a Compressed | |
| Read-Only File System). Squashfs is a highly compressed read-only | |
| filesystem for Linux. It uses zlib/lzo compression to compress both | |
| files, inodes and directories. Inodes in the system are very small | |
| and all blocks are packed to minimise data overhead. Block sizes | |
| greater than 4K are supported up to a maximum of 1 Mbytes (default | |
| block size 128K). SquashFS 4.0 supports 64 bit filesystems and files | |
| (larger than 4GB), full uid/gid information, hard links and | |
| timestamps. | |
| Squashfs is intended for general read-only filesystem use, for | |
| archival use (i.e. in cases where a .tar.gz file may be used), and in | |
| embedded systems where low overhead is needed. Further information | |
| and tools are available from http://squashfs.sourceforge.net. | |
| If you want to compile this as a module ( = code which can be | |
| inserted in and removed from the running kernel whenever you want), | |
| say M here and read <file:Documentation/modules.txt>. The module | |
| will be called squashfs. Note that the root file system (the one | |
| containing the directory /) cannot be compiled as a module. | |
| If unsure, say N. | |
| config SQUASHFS_XATTR | |
| bool "Squashfs XATTR support" | |
| depends on SQUASHFS | |
| help | |
| Saying Y here includes support for extended attributes (xattrs). | |
| Xattrs are name:value pairs associated with inodes by | |
| the kernel or by users (see the attr(5) manual page). | |
| If unsure, say N. | |
| config SQUASHFS_LZO | |
| bool "Include support for LZO compressed file systems" | |
| depends on SQUASHFS | |
| select LZO_DECOMPRESS | |
| help | |
| Saying Y here includes support for reading Squashfs file systems | |
| compressed with LZO compresssion. LZO compression is mainly | |
| aimed at embedded systems with slower CPUs where the overheads | |
| of zlib are too high. | |
| LZO is not the standard compression used in Squashfs and so most | |
| file systems will be readable without selecting this option. | |
| If unsure, say N. | |
| config SQUASHFS_XZ | |
| bool "Include support for XZ compressed file systems" | |
| depends on SQUASHFS | |
| select XZ_DEC | |
| help | |
| Saying Y here includes support for reading Squashfs file systems | |
| compressed with XZ compresssion. XZ gives better compression than | |
| the default zlib compression, at the expense of greater CPU and | |
| memory overhead. | |
| XZ is not the standard compression used in Squashfs and so most | |
| file systems will be readable without selecting this option. | |
| If unsure, say N. | |
| config SQUASHFS_EMBEDDED | |
| bool "Additional option for memory-constrained systems" | |
| depends on SQUASHFS | |
| help | |
| Saying Y here allows you to specify cache size. | |
| If unsure, say N. | |
| config SQUASHFS_FRAGMENT_CACHE_SIZE | |
| int "Number of fragments cached" if SQUASHFS_EMBEDDED | |
| depends on SQUASHFS | |
| default "3" | |
| help | |
| By default SquashFS caches the last 3 fragments read from | |
| the filesystem. Increasing this amount may mean SquashFS | |
| has to re-read fragments less often from disk, at the expense | |
| of extra system memory. Decreasing this amount will mean | |
| SquashFS uses less memory at the expense of extra reads from disk. | |
| Note there must be at least one cached fragment. Anything | |
| much more than three will probably not make much difference. |