NAME

       mkfs.jffs2 - Create a JFFS2 file system image from directory

SYNOPSIS

       mkfs.jffs2  [  -p,--pad[=SIZE]  ]  [  -r,-d,--root  directory  ]  [ -s,--pagesize=SIZE ] [
       -e,--eraseblock=SIZE ] [ -c,--cleanmarker=SIZE ] [ -n,--no-cleanmarkers  ]  [  -o,--output
       image.jffs2  ]  [  -l,--little-endian  ]  [  -b,--big-endian  ]  [  -D,--devtable=FILE ] [
       -f,--faketime ] [ -q,--squash ] [ -U,--squash-uids ] [ -P,--squash-perms ] [  --with-xattr
       ]  [  --with-selinux ] [ --with-posix-acl ] [ -m,--compression-mode=MODE ] [ -x,--disable-
       compressor=NAME ] [ -X,--enable-compressor=NAME ] [ -y,--compressor-priority=PRIORITY:NAME
       ]  [  -L,--list-compressors  ]  [ -t,--test-compression ] [ -h,--help ] [ -v,--verbose ] [
       -V,--version ] [ -i,--incremental image.jffs2 ]

DESCRIPTION

       The program mkfs.jffs2 creates a JFFS2 (Second Journalling Flash File System) file  system
       image  and writes the resulting image to the file specified by the -o option or by default
       to the standard output, unless the standard output is a  terminal  device  in  which  case
       mkfs.jffs2 will abort.

       The  file  system  image  is  created  using  the  files  and directories contained in the
       directory specified by the option -r or the present directory, if the  -r  option  is  not
       specified.

       Each  block  of the files to be placed into the file system image are compressed using one
       of the available compressors depending on the selected compression mode.

       File systems are created with the same endianness as the host, unless the -b or -l options
       are specified.  JFFS2 driver in the 2.4 Linux kernel only supported images having the same
       endianness as the CPU. As of 2.5.48, the kernel can be changed with a  #define  to  accept
       images of the non-native endianness. Full bi-endian support in the kernel is not planned.

       It  is  unlikely  that  JFFS2  images are useful except in conjuction with the MTD (Memory
       Technology Device) drivers in the Linux kernel, since the JFFS2 file system driver in  the
       kernel requires MTD devices.

OPTIONS

       Options  that  take SIZE arguments can be specified as either decimal (e.g., 65536), octal
       (0200000), or hexidecimal (0x1000).

       -p, --pad[=SIZE]
              Pad output to SIZE bytes with 0xFF.  If SIZE is not specified, the output is padded
              to the end of the final erase block.

       -r, -d, --root=DIR
              Build file system from directory DIR.  The default is the current directory.

       -s, --pagesize=SIZE
              Use page size SIZE.  The default is 4 KiB.  This size is the maximum size of a data
              node.  Set according to target system's memory management page size (NOTE: this  is
              NOT related to NAND page size).

       -e, --eraseblock=SIZE
              Use  erase  block size SIZE.  The default is 64 KiB.  If you use a erase block size
              different than the erase block size of the target MTD device, JFFS2 may not perform
              optimally. If the SIZE specified is below 4096, the units are assumed to be KiB.

       -c, --cleanmarker=SIZE
              Write  ´CLEANMARKER´  nodes with the size specified. It is not normally appropriate
              to specify a size other than the default 12 bytes.

       -n, --no-cleanmarkers
              Do not write ´CLEANMARKER´ nodes to the beginning of each erase block. This  option
              can  be  useful  for  creating JFFS2 images for use on NAND flash, and for creating
              images which are to be used on a variety  of  hardware  with  differing  eraseblock
              sizes.

       -o, --output=FILE
              Write JFFS2 image to file FILE.  Default is the standard output.

       -l, --little-endian
              Create  a  little-endian  JFFS2  image.   Default is to make an image with the same
              endianness as the host.

       -b, --big-endian
              Create a big-endian JFFS2 image.  Default  is  to  make  an  image  with  the  same
              endianness as the host.

       -D, --devtable=FILE
              Use  the  named  FILE  as  a  device table file, for including devices and changing
              permissions  in  the  created  image  when  the  user  does  not  have  appropriate
              permissions to create them on the file system used as source.

       -f, --faketime
              Change all file timestamps to ´0´ for regression testing.

       -q, --squash
              Squash permissions and owners, making all files be owned by root and removing write
              permission for ´group´ and ´other´.

       -U, --squash-uids
              Squash owners making all files be owned by root.

       -P, --squash-perms
              Squash permissions, removing write permission for ´group´ and ´other´.

       --with-xattr
              Enables xattr, stuff all xattr entries into jffs2 image file.

       --with-selinux
              Enables xattr, stuff only SELinux Labels into jffs2 image file.

       --with-posix-acl
              Enable xattr, stuff only POSIX ACL entries into jffs2 image file.

       -m, --compression-mode=MODE
              Set the default compression mode. The default mode  is  priority  which  tries  the
              compressors  in  a  predefinied  order  and  chooses  the first successful one. The
              alternatives are: none (mkfs will  not  compress)  and  size  (mkfs  will  try  all
              compressor and chooses the one which have the smallest result).

       -x, --disable-compressor=NAME
              Disable a compressor. Use -L to see the list of the available compressors and their
              default states.

       -X, --enable-compressor=NAME
              Enable a compressor. Use -L to see the list of the available compressors and  their
              default states.

       -y, --compressor-priority=PRIORITY:NAME
              Set  the  priority  of  a  compressor.  Use  -L  to  see  the list of the available
              compressors  and  their  default  priority.   Priorities  are  used   by   priority
              compression mode.

       -L, --list-compressors
              Show the list of the available compressors and their states.

       -t, --test-compression
              Call  decompress  after  every  compress - and compare the result with the original
              data -, and some other check.

       -h, --help
              Display help text.

       -v, --verbose
              Verbose operation.

       -V, --version
              Display version information.

       -i, --incremental=FILE
              Generate an appendage image for FILE. If FILE is written  to  flash  and  flash  is
              appended with the output, then it seems as if it was one thing.

LIMITATIONS

       The format and grammar of the device table file does not allow it to create symbolic links
       when the symbolic links are not already present in the root working directory.

       However, symbolic links may be specified in the device table file using the l type for the
       purposes of setting their permissions and ownership.

BUGS

       JFFS2 limits device major and minor numbers to 8 bits each.  Some consider this a bug.

       mkfs.jffs2  does  not  properly  handle  hard  links  in  the  input  directory structure.
       Currently, hard linked files will be expanded to multiple identical files  in  the  output
       image.

AUTHORS

       David Woodhouse
       Manual page written by David Schleef <ds@schleef.org>

SEE ALSO

       mkfs(8), mkfs.jffs(1), fakeroot(1)

                                                                                    MKFS.JFFS2(1)