From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Brian L. Stuart" <blstuart@bellsouth.net>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
Date: Wed, 28 May 2008 19:34:18 +0000
Message-Id: <052820081934.14135.483DB3BA0007BF150000373722230647029B0A02D2089B9A019C04040A0DBF9B9D0E9A9B9C040D@att.net>
In-Reply-To: <20080515223326.9DE911E8C4D@holo.morphisms.net>
References: <051520082104.12919.482CA554000D264E0000327722218683269B0A02D2089B9A019C04040A0DBF9B9D0E9A9B9C040D@att.net>
	<20080515223326.9DE911E8C4D@holo.morphisms.net>
Subject: Re: [9fans] P9P on Solaris
Topicbox-Message-UUID: ae0f9120-ead3-11e9-9d60-3106f5b1d025

> That's probably because the stack pointer points at
> the wrong end of the stack.  There are some magic
> #defines you can put in that change the meaning of
> ...
> Once you get the thread library working,
> you will probably have to add support for
> the Solaris FS to libdiskfs, unless it is the
> same FFS that BSD uses.

I know it's been a while, but that got me farther.  The
odd thing is that I had already played with the magic
define, but it seems that __sun__ wasn't getting set.
I'll take a look at that before I send any patches.
It turns out that Solaris does use the FFS, but it
uses version 1.  So I did some work on V1 to get it
working.  I'm hoping that all the other instances of
FFS are V2 so that we don't have to figure out some
way to handle both.

Anyway, the main changes:
- It would appear that FFS V2 specifies most things
in terms of blocks, but V1 in terms of fragments.
I think the changes I made to handle V1 will still
work with V2, but I don't have a V2 machine set up
at the moment to test it on.
- There's also a discrepancy between the V1 inode
defined in ffs.h and the one defined in the Solaris
header files.  It ends up messing up the UID and
GID fields.
- Then there's byte ordering.  In the setup I'm playing
with, venti is running on a 386 taking vbackup blocks
from a SPARC. So I added conditional byte swapping
to the handling of the superblock, the cylinder blocks,
the inodes and the directory entries.  It basically
looks at the magic number and if it would be correct
swapped, we take that as good enough and set a flag
to swap everything.
- Because I'm introducing venti into a UNIX environment
instead of putting a UNIX machine in a Plan 9 environment,
I need to at least have the option of traditional
superuser behavior.  So I added an insecure (-i) flag
to vnfs.  It turns off the mapping from UID/GID 0 to
-1.  Then in ffs.c, I allowed the traditional uid 0
gets all access.

I think that's all.  At least it's the big stuff.  Once
I get the code cleaned up, I'll send some patches.

Thanks for the help,
BLS