haiku/docs/develop/file_systems/ufs2.rst

The UFS2 filesystem
===============================

While making a device for testing I have used a usb drive and formatted it to
UFS2 by using the following commands in FreeBSD. Here da0 is usb.

	gpart destroy -F /dev/da0

	gpart create -s gpt /dev/da0

	gpart add -t freebsd-ufs /dev/da0

	newfs /dev/da0p1

By running the following commands you can run the implemented code of UFS2.

Commands
--------

# Building the ufs2 shell

	jam -q "<build>ufs2_shell"

To run it, use

	jam run objects/linux/x86_64/release/tests/add-ons/kernel/file_systems/ufs2/ufs2_shell/ufs2_shell <path_to_the_image>

If you are using a usb drive then you may not be able to open it so, you just
need to add sudo in the beginning of above command and make sure that you have
not mounted the usb drive.

Alternatively you can start from an existing freebsd image, so it has some files in it:

	Download FreeBSD-12.1-RELEASE-amd64-mini-memstick.img

	diskimage register FreeBSD-12.1-RELEASE-amd64-mini-memstick.img to access the MBR style partitions inside it (on Linux probably using mount -o loop or something like that)

	dd if=/dev/disk/virtual/files/8/1 bs=8K skip=1 of=fbsd_ufstest.img to extract the filesystem from the partition (skipping the freebsd disklabel)

	Check the result: file fbsd_ufstest.img

fbsd_ufstest.img: Unix Fast File system [v2] (little-endian)

During the implementation of the project the following links were found useful.
https://github.com/freebsd/freebsd/blob/master/sys/ufs/ffs/fs.h
https://flylib.com/books/en/2.48.1/ufs2_inodes.html
Generate developer docs with Sphinx An effort was started some time ago to consolidate all internal documentation in the git tree. However, this was just an accumulation of files in various formats without any strucutre or way to browse it, which results in no one even knowing that we have docs here. This converts most of the files to restructuredtext and uses Sphinx to generate an HTML browsable user manual (with a table of content and a first attempt to put things in a global hierarchy). There are almost no changes to the documentation content in this commit (some obviously obsolete things were removed). The plan is to get the toolchain up and running to make these docs easily available, and only then see about improving the content. We can migrate some things off the wiki and website, and rework the table of contents to have some more hierarchy levels because currently it's a bit messy. Change-Id: I924ac9dc6e753887ab56f18a09bdb0a1e1793bfd Reviewed-on: https://review.haiku-os.org/c/haiku/+/4370 Reviewed-by: Niels Sascha Reedijk <niels.reedijk@gmail.com> 2021-08-24 18:45:36 +03:00			`The UFS2 filesystem`
ufs2: Reading inodes of ufs2. Now file system can be mounted sucessfully. Adding documentation for using the code. Change-Id: I2bd1b72e06ffc3b5f6306aaa69c59becf4cb882b Reviewed-on: https://review.haiku-os.org/c/haiku/+/2696 Reviewed-by: Adrien Destugues <pulkomandy@gmail.com> 2020-05-14 16:50:14 +03:00			`===============================`

			`While making a device for testing I have used a usb drive and formatted it to`
			`UFS2 by using the following commands in FreeBSD. Here da0 is usb.`

			`gpart destroy -F /dev/da0`

			`gpart create -s gpt /dev/da0`

			`gpart add -t freebsd-ufs /dev/da0`

			`newfs /dev/da0p1`

			`By running the following commands you can run the implemented code of UFS2.`

			`Commands`
			`--------`

			`# Building the ufs2 shell`

			`jam -q "<build>ufs2_shell"`

			`To run it, use`

			`jam run objects/linux/x86_64/release/tests/add-ons/kernel/file_systems/ufs2/ufs2_shell/ufs2_shell <path_to_the_image>`

			`If you are using a usb drive then you may not be able to open it so, you just`
			`need to add sudo in the beginning of above command and make sure that you have`
			`not mounted the usb drive.`

			`Alternatively you can start from an existing freebsd image, so it has some files in it:`

			`Download FreeBSD-12.1-RELEASE-amd64-mini-memstick.img`

			`diskimage register FreeBSD-12.1-RELEASE-amd64-mini-memstick.img to access the MBR style partitions inside it (on Linux probably using mount -o loop or something like that)`

			`dd if=/dev/disk/virtual/files/8/1 bs=8K skip=1 of=fbsd_ufstest.img to extract the filesystem from the partition (skipping the freebsd disklabel)`

			`Check the result: file fbsd_ufstest.img`

			`fbsd_ufstest.img: Unix Fast File system [v2] (little-endian)`

			`During the implementation of the project the following links were found useful.`
			`https://github.com/freebsd/freebsd/blob/master/sys/ufs/ffs/fs.h`
			`https://flylib.com/books/en/2.48.1/ufs2_inodes.html`