On Mon, Mar 2, 2020 at 11:39 PM Adrien Destugues
<pulkomandy@xxxxxxxxxxxxx> wrote:
I have compiled Haiku and I am running it on my virtual machine.
I want to work on UFS2 file system.
Ok, in that case the first step will be to create some directories and
Jamfiles in Haiku
to add the new filesystem to it. You can look at
https://review.haiku-os.org/c/haiku/+/2096
as a reference, it recently added similar things for the XFS filesystem.
The idea is to get an "fs_shell" running. This is an application that will
run the filesystem
code in a controlled environment and allow to run specific parts of the code
through a command
line interface, with the availability of an user-space debugger. It makes it
a lot simpler to
test the filesystem code.
You will need to read about the structure of the filesystem, an entry point
for this is the
wikiepdia article (https://en.wikipedia.org/wiki/Unix_File_System) and in
particular the references:
- The original specifications:
https://people.eecs.berkeley.edu/~brewer/cs262/FFS.pdf
- The 64bit extensions:
https://www.usenix.org/legacy/events/bsdcon03/tech/full_papers/mckusick/mckusick_html/
- The variant implemented in Solaris (which may be a bit different from the
one in FreeBSD):
http://ptgmedia.pearsoncmg.com/images/0131482092/samplechapter/mcdougall_ch15.pdf
Once you have some understanding of the filesystem structure, you should be
able to start
implementing the first commands of the fs_shell, to identify (recognize if
it's ufs or not)
and then mount a filesystem image.
