4b676d2dbe
Update compression types supported and add some help text for the LZO Kconfig option. Also add missing "default n" line and make some trivial whitespace cleanups too. Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk>
78 lines
2.8 KiB
Plaintext
78 lines
2.8 KiB
Plaintext
config SQUASHFS
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tristate "SquashFS 4.0 - Squashed file system support"
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depends on BLOCK
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select ZLIB_INFLATE
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help
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Saying Y here includes support for SquashFS 4.0 (a Compressed
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Read-Only File System). Squashfs is a highly compressed read-only
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filesystem for Linux. It uses zlib/lzo compression to compress both
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files, inodes and directories. Inodes in the system are very small
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and all blocks are packed to minimise data overhead. Block sizes
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greater than 4K are supported up to a maximum of 1 Mbytes (default
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block size 128K). SquashFS 4.0 supports 64 bit filesystems and files
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(larger than 4GB), full uid/gid information, hard links and
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timestamps.
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Squashfs is intended for general read-only filesystem use, for
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archival use (i.e. in cases where a .tar.gz file may be used), and in
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embedded systems where low overhead is needed. Further information
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and tools are available from http://squashfs.sourceforge.net.
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If you want to compile this as a module ( = code which can be
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inserted in and removed from the running kernel whenever you want),
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say M here and read <file:Documentation/modules.txt>. The module
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will be called squashfs. Note that the root file system (the one
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containing the directory /) cannot be compiled as a module.
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If unsure, say N.
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config SQUASHFS_XATTR
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bool "Squashfs XATTR support"
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depends on SQUASHFS
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default n
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help
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Saying Y here includes support for extended attributes (xattrs).
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Xattrs are name:value pairs associated with inodes by
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the kernel or by users (see the attr(5) manual page).
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If unsure, say N.
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config SQUASHFS_LZO
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bool "Include support for LZO compressed file systems"
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depends on SQUASHFS
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default n
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select LZO_DECOMPRESS
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help
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Saying Y here includes support for reading Squashfs file systems
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compressed with LZO compresssion. LZO compression is mainly
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aimed at embedded systems with slower CPUs where the overheads
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of zlib are too high.
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LZO is not the standard compression used in Squashfs and so most
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file systems will be readable without selecting this option.
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If unsure, say N.
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config SQUASHFS_EMBEDDED
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bool "Additional option for memory-constrained systems"
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depends on SQUASHFS
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default n
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help
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Saying Y here allows you to specify cache size.
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If unsure, say N.
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config SQUASHFS_FRAGMENT_CACHE_SIZE
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int "Number of fragments cached" if SQUASHFS_EMBEDDED
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depends on SQUASHFS
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default "3"
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help
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By default SquashFS caches the last 3 fragments read from
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the filesystem. Increasing this amount may mean SquashFS
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has to re-read fragments less often from disk, at the expense
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of extra system memory. Decreasing this amount will mean
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SquashFS uses less memory at the expense of extra reads from disk.
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Note there must be at least one cached fragment. Anything
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much more than three will probably not make much difference.
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