config JFFS2_FS
|
tristate "Journalling Flash File System v2 (JFFS2) support"
|
select CRC32
|
depends on MTD
|
help
|
JFFS2 is the second generation of the Journalling Flash File System
|
for use on diskless embedded devices. It provides improved wear
|
levelling, compression and support for hard links. You cannot use
|
this on normal block devices, only on 'MTD' devices.
|
|
Further information on the design and implementation of JFFS2 is
|
available at <http://sources.redhat.com/jffs2/>.
|
|
config JFFS2_FS_DEBUG
|
int "JFFS2 debugging verbosity (0 = quiet, 2 = noisy)"
|
depends on JFFS2_FS
|
default "0"
|
help
|
This controls the amount of debugging messages produced by the JFFS2
|
code. Set it to zero for use in production systems. For evaluation,
|
testing and debugging, it's advisable to set it to one. This will
|
enable a few assertions and will print debugging messages at the
|
KERN_DEBUG loglevel, where they won't normally be visible. Level 2
|
is unlikely to be useful - it enables extra debugging in certain
|
areas which at one point needed debugging, but when the bugs were
|
located and fixed, the detailed messages were relegated to level 2.
|
|
If reporting bugs, please try to have available a full dump of the
|
messages at debug level 1 while the misbehaviour was occurring.
|
|
config JFFS2_FS_WRITEBUFFER
|
bool "JFFS2 write-buffering support"
|
depends on JFFS2_FS
|
default y
|
help
|
This enables the write-buffering support in JFFS2.
|
|
This functionality is required to support JFFS2 on the following
|
types of flash devices:
|
- NAND flash
|
- NOR flash with transparent ECC
|
- DataFlash
|
|
config JFFS2_FS_WBUF_VERIFY
|
bool "Verify JFFS2 write-buffer reads"
|
depends on JFFS2_FS_WRITEBUFFER
|
default n
|
help
|
This causes JFFS2 to read back every page written through the
|
write-buffer, and check for errors.
|
|
config JFFS2_SUMMARY
|
bool "JFFS2 summary support"
|
depends on JFFS2_FS
|
default n
|
help
|
This feature makes it possible to use summary information
|
for faster filesystem mount.
|
|
The summary information can be inserted into a filesystem image
|
by the utility 'sumtool'.
|
|
If unsure, say 'N'.
|
|
config JFFS2_FS_XATTR
|
bool "JFFS2 XATTR support"
|
depends on JFFS2_FS
|
default n
|
help
|
Extended attributes are name:value pairs associated with inodes by
|
the kernel or by users (see the attr(5) manual page for details).
|
|
If unsure, say N.
|
|
config JFFS2_FS_POSIX_ACL
|
bool "JFFS2 POSIX Access Control Lists"
|
depends on JFFS2_FS_XATTR
|
default y
|
select FS_POSIX_ACL
|
help
|
Posix Access Control Lists (ACLs) support permissions for users and
|
groups beyond the owner/group/world scheme.
|
|
If you don't know what Access Control Lists are, say N
|
|
config JFFS2_FS_SECURITY
|
bool "JFFS2 Security Labels"
|
depends on JFFS2_FS_XATTR
|
default y
|
help
|
Security labels support alternative access control models
|
implemented by security modules like SELinux. This option
|
enables an extended attribute handler for file security
|
labels in the jffs2 filesystem.
|
|
If you are not using a security module that requires using
|
extended attributes for file security labels, say N.
|
|
config JFFS2_COMPRESSION_OPTIONS
|
bool "Advanced compression options for JFFS2"
|
depends on JFFS2_FS
|
default n
|
help
|
Enabling this option allows you to explicitly choose which
|
compression modules, if any, are enabled in JFFS2. Removing
|
compressors can mean you cannot read existing file systems,
|
and enabling experimental compressors can mean that you
|
write a file system which cannot be read by a standard kernel.
|
|
If unsure, you should _definitely_ say 'N'.
|
|
config JFFS2_ZLIB
|
bool "JFFS2 ZLIB compression support" if JFFS2_COMPRESSION_OPTIONS
|
select ZLIB_INFLATE
|
select ZLIB_DEFLATE
|
depends on JFFS2_FS
|
default y
|
help
|
Zlib is designed to be a free, general-purpose, legally unencumbered,
|
lossless data-compression library for use on virtually any computer
|
hardware and operating system. See <http://www.gzip.org/zlib/> for
|
further information.
|
|
Say 'Y' if unsure.
|
|
config JFFS2_LZO
|
bool "JFFS2 LZO compression support" if JFFS2_COMPRESSION_OPTIONS
|
select LZO_COMPRESS
|
select LZO_DECOMPRESS
|
depends on JFFS2_FS
|
default n
|
help
|
minilzo-based compression. Generally works better than Zlib.
|
|
This feature was added in July, 2007. Say 'N' if you need
|
compatibility with older bootloaders or kernels.
|
|
config JFFS2_RTIME
|
bool "JFFS2 RTIME compression support" if JFFS2_COMPRESSION_OPTIONS
|
depends on JFFS2_FS
|
default y
|
help
|
Rtime does manage to recompress already-compressed data. Say 'Y' if unsure.
|
|
config JFFS2_RUBIN
|
bool "JFFS2 RUBIN compression support" if JFFS2_COMPRESSION_OPTIONS
|
depends on JFFS2_FS
|
default n
|
help
|
RUBINMIPS and DYNRUBIN compressors. Say 'N' if unsure.
|
|
choice
|
prompt "JFFS2 default compression mode" if JFFS2_COMPRESSION_OPTIONS
|
default JFFS2_CMODE_PRIORITY
|
depends on JFFS2_FS
|
help
|
You can set here the default compression mode of JFFS2 from
|
the available compression modes. Don't touch if unsure.
|
|
config JFFS2_CMODE_NONE
|
bool "no compression"
|
help
|
Uses no compression.
|
|
config JFFS2_CMODE_PRIORITY
|
bool "priority"
|
help
|
Tries the compressors in a predefined order and chooses the first
|
successful one.
|
|
config JFFS2_CMODE_SIZE
|
bool "size"
|
help
|
Tries all compressors and chooses the one which has the smallest
|
result.
|
|
config JFFS2_CMODE_FAVOURLZO
|
bool "Favour LZO"
|
help
|
Tries all compressors and chooses the one which has the smallest
|
result but gives some preference to LZO (which has faster
|
decompression) at the expense of size.
|
|
endchoice
|
