Ubuntu Manpage: makefs — create a filesystem image from a directory tree

Provided by: makefs_20190105-3_amd64

NAME

       makefs — create a filesystem image from a directory tree

SYNOPSIS

       makefs   [-x]   [-B   byte-order]   [-b  free-blocks]  [-d  debug-mask]  [-F  specfile]  [-f  free-files]
              [-M  minimum-size]  [-m  maximum-size]  [-N   userdb-dir]   [-o   fs-options]   [-S   sector-size]
              [-s image-size] [-t fs-type] [-T maximum-time] image-file directory

DESCRIPTION

The utility makefs creates a filesystem image into image-file from the directory tree directory. No
special devices or privileges are required to perform this task.

The options are as follows:

-B byte-order
Set the byte order of the image to byte-order. Valid byte orders are ‘4321’, ‘big’, or ‘be’ for
big endian, and ‘1234’, ‘little’, or ‘le’ for little endian. Some filesystems may have a fixed
byte order; in those cases this argument will be ignored.

-b free-blocks
Ensure that a minimum of free-blocks free blocks exist in the image. An optional ‘%’ suffix may be
provided to indicate that free-blocks indicates a percentage of the calculated image size.

-d debug-mask
Enable various levels of debugging, depending upon which bits are set in debug-mask. XXX: document
these

-F specfile
Use specfile as an mtree(8) ‘specfile’ specification.

If a specfile entry exists in the underlying filesystem, its permissions and modification time will
be used unless specifically overridden by the specfile. An error will be raised if the type of
entry in the specfile conflicts with that of an existing entry.

In the opposite case (where a specfile entry does not have an entry in the underlying filesystem)
the following occurs: If the specfile entry is marked optional, the specfile entry is ignored.
Otherwise, the entry will be created in the image, and it is necessary to specify at least the
following parameters in the specfile: type, mode, gname, or gid, and uname or uid, device (in the
case of block or character devices), and link (in the case of symbolic links). If time isn't
provided, the current time will be used. If flags isn't provided, the current file flags will be
used. Missing regular file entries will be created as zero-length files.

-f free-files
Ensure that a minimum of free-files free files (inodes) exist in the image. An optional ‘%’ suffix
may be provided to indicate that free-files indicates a percentage of the calculated image size.

-M minimum-size
Set the minimum size of the filesystem image to minimum-size.

-m maximum-size
Set the maximum size of the filesystem image to maximum-size. An error will be raised if the
target filesystem needs to be larger than this to accommodate the provided directory tree.

-N dbdir
Use the user database text file master.passwd and group database text file group from dbdir, rather
than using the results from the system's getpwnam(3) and getgrnam(3) (and related) library calls.

-o fs-options
Set filesystem specific options. fs-options is a comma separated list of options. Valid
filesystem specific options are detailed below.

-S sector-size
Set the filesystem sector size to sector-size. Defaults to 512.

-s image-size
Set the size of the filesystem image to image-size.

-t fs-type
Create an fs-type filesystem image. The following filesystem types are supported:

ffs BSD fast filesystem (default).

cd9660 ISO 9660 filesystem.

-T maximum-time
Clamp superblock and file timestamps to maximum-time seconds since the Epoch.

-x Exclude filesystem nodes not explicitly listed in the specfile.

Where sizes are specified, a decimal number of bytes is expected. Two or more numbers may be separated
by an “x” to indicate a product. Each number may have one of the following optional suffixes:
b Block; multiply by 512
k Kibi; multiply by 1024 (1 KiB)
m Mebi; multiply by 1048576 (1 MiB)
g Gibi; multiply by 1073741824 (1 GiB)
t Tebi; multiply by 1099511627776 (1 TiB)
w Word; multiply by the number of bytes in an integer

FFS-specific options
ffs images have ffs-specific optional parameters that may be provided. Each of the options consists of a
keyword, an equal sign (‘=’), and a value. The following keywords are supported:

avgfilesize Expected average file size.
avgfpdir Expected number of files per directory.
bsize Block size.
density Bytes per inode.
fsize Fragment size.
maxbpg Maximum blocks per file in a cylinder group.
minfree Minimum % free.
optimization Optimization preference; one of ‘space’ or ‘time’.
extent Maximum extent size.
maxbpcg Maximum total number of blocks in a cylinder group.
version UFS version. 1 for FFS (default), 2 for UFS2.

CD9660-specific options
cd9660 images have ISO9660-specific optional parameters that may be provided. The arguments consist of a
keyword and, optionally, an equal sign (‘=’), and a value. The following keywords are supported:

allow-deep-trees Allow the directory structure to exceed the maximum specified in the spec.
allow-max-name Allow 37 instead of 33 characters for filenames by omitting the version id.
allow-multidot Allow multiple dots in a filename.
applicationid Application ID of the image.
archimedes Use the ‘ARCHIMEDES’ extension to encode RISC OS metadata.
boot-info-table Write a legacy 56-byte table at offset 8 into the boot image (see below).
boot-load-segment Set load segment for the boot image.
bootimage Filename of a boot image in the format “sysid;filename”, where “sysid” is one
of ‘i386’, ‘mac68k’, ‘macppc’, or ‘powerpc’.
creation-date Override PVD creation date.
effective-date Override PVD effective date.
expiration-date Override PVD expiration date.
generic-bootimage Load a generic boot image into the first 32K of the cd9660 image.
hard-disk-boot Boot image is a hard disk image.
hide-rr-moved Assign the RR_MOVED directory a rock ridge name of the empty string instead
of the default .rr_moved.
keep-bad-images Don't throw away images whose write was aborted due to an error. For
debugging purposes.
label Label name of the image.
modification-date Override PVD modification date.
no-boot Boot image is not bootable.
no-emul-boot Boot image is a “no emulation” ElTorito image.
no-trailing-padding Do not pad the image (apparently Linux needs the padding).
omit-trailing-period Violate the standard, do not append a trailing period to filenames without an
extension.
preparer Preparer ID of the image.
publisher Publisher ID of the image.
rockridge Use RockRidge extensions (for longer filenames, etc.).
rr-squash Force uid 0, gid 0, and rationalised permission bits for RockRidge entries.
volumeid Volume set identifier of the image.

The boot-info-table currently consists of the following fields (all 7.3.1 numbers), offsets relative to
the boot image:
0 8 bytes: kept as is, not part of checksum
8 LBA of PVD
12 LBA of boot image
16 Size in bytes of boot image
20 32-bit additive sum of all 32-bit words of boot image
24 40 reserved bytes (MBZ)
64 Begin of checksummed data, kept as is

Dates (to override) are in 8.4.26.1 format (YYYYmmddHHMMSS00) and Universal Time, i.e. with zero offset
from Greenwich Mean Time.

HISTORY

       The makefs utility appeared in NetBSD 1.6.

       Support for overriding PVD dates and the boot info table was added in MirBSD 11.

AUTHORS

       Luke Mewburn <lukem@NetBSD.org> (original program)
       Daniel Watt,
       Walter Deignan,
       Ryan Gabrys,
       Alan Perez-Rathke,
       Ram Vedam (cd9660 support)
       Thorsten Glaser <tg@mirbsd.org>

CAVEATS