KFS(4)KFS(4)NAMEkfs - disk file system
SYNOPSIS
mount {disk/kfs [-r [ -b bsize ] ] [-c] [-A] [-P] [-R] [-W] [ -n name ]
file} dir
DESCRIPTION
Kfs implements a hierarchical Inferno file system within an existing
file, which is typically a disk or flash memory partition. It gives
access to it through the 9P protocol on its standard input, and the
contents can be mounted directly on a given dir as shown above. The
file system format is the same as that used by the kfs command of Plan
9, except that the modification user ID is implemented.
The -r option causes the file system to be reset to an initially empty
state (`reamed'). Permission checking is turned off, to allow any
desired permissions and file ownership to be set. (In other words, the
-W and -P options are also set by default.) The file system block size
is set to the bsize given by the -b option (default: 1024 bytes), which
must be a multiple of 512 and not greater than 16k bytes. The block
size is stored in the file and need not be given again. The storage
representation is always little-endian.
Otherwise, the file system is checked if required, unless the -c option
is given.
The contents of the file system can be provided by using commands such
as mkdir(1), cp(1) and rm(1) in dir, or built from a description using
mkfs(8).
The mapping between user names and internal IDs within the file system
is established by the file adm/users (within the file system itself) as
described by users(6), which kfs reads when it starts. If no such file
exists, as for instance when the file system is initially empty, kfs
uses a minimal set corresponding to the following users(6) file:
-1:adm:adm:
0:none:adm:
9999:noworld::
10000:sys::
10001:upas:upas:
10002:bootes:bootes:
10006:inferno::
Any users(6) file used with kfs should include entries for at least
adm, none, and noworld as above (although group membership can vary).
Kfs can optionally serve a control file, for use by kfscmd(8). If the
-n option is given, kfs creates a channel /chan/kfs.name.cmd and
accepts commands on it from the user that started kfs.
Other options are:
-A do not update access times; useful when running a file system in
flash over ftl(3), to avoid excessive wear
-P suppress permission checking
-R file system is read only
-W allow wstat (see sys-stat(2) or stat(5)) to make arbitrary
changes to user and group fields
EXAMPLES
Create an empty file system in the file kfs.file. Because the file
system will be no larger than the existing file's size, and the file is
assumed not to be a device file, use zeros(1) to prepare a file with
2048 blocks of 1024 bytes each:
zeros 1024 2048 >kfs.file
mount -c {disk/kfs -r kfs.file} /n/local
The -c option to mount allows files to be created in /n/local.
SOURCE
/appl/cmd/disk/kfs.b
SEE ALSOdd(1), zeros(1), flash(3), ftl(3), logfs(3), sd(3), users(6),
kfscmd(8), mkfs(8)BUGS
Because the file system format is the same as Plan 9's kfs, this one
also does not support file names longer than 27 bytes. It likewise
cannot cope with files bigger than 2ⁱ-1 bytes.
KFS(4)
