Subject: Re: Fwd: A JBD file-system (generic Journal file for ext2)
To: Avinash Malik <>
From: Bill Stouder-Studenmund <>
List: tech-kern
Date: 09/21/2007 10:13:27
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On Fri, Sep 21, 2007 at 06:23:07PM +1200, Avinash Malik wrote:
> Quoting Bill Stouder-Studenmund <>:
> > It's not really "fs_commit". It's "journal format commit" where the
> > journal formats are closely related to specific other fs implementation=
> > We won't really have an "ext3fs_commit" but we will have a "jbd_commit"
> > for a journal that is layed out how ext3fs/jbd expect.
> Just to make my understanding clear before I get into coding it, this is =
what I
> understand from the above statement:
>   The commit functionality will still be implemented as a function in the
> file-system, and there will be host of commit functions one for each
> Journal-type, depending upon how many journaling type each file-system wa=
nts to
> support. The ufs_trans_attr structure containing the gj_commit function p=
> will point to the appropriate journal commit function (which is implement=
ed in
> the file-system) and this gets initialized as it is being done right now
> correct?

Don't worry about where exatly the commit function is implemented. Chances
are it won't actually be in the file system itself, but it will be in a
library. The important thing is that the file system(s) will know how to
find it.

In fact it will most likely be in a library as multiple file systems may=20
want the same journal routine, and we'll only have one version of it. As=20
Adam noted, multiple Linux file systems use jbd, so they'll all want to=20

> I don't know if this is the right place to ask this question but, normall=
y I use
> Freebsd and I installed NETBSD-3.1 to start-coding, everything went norma=
> until it came to networking when I dhclient rtk0, I get an IP but no netm=
ask at
> all it remain at 0xfff..000. It is a real hassel using freebsd to import =
> packages on disk and then booting into NETBSD to start coding. Any help w=
> regards to this is appreciated. I tried static IPing the interface, it do=
es the
> same thing, command "ifconfig rtk0 down ; ifconfig rtk0 netmask
>" goes through but netmask does not get assigned at all remains =
> to 0xff..000.

Get one of the NetBSD 4.0 release candidate builds. Then start following=20
current and look at switching to it (-current can be rough at times when=20
there is temporary breakage). The journaling will make it into 5.0 at the=
earliest, and the kernel is VERY different from 4.0 and exceptionally=20
different from 3.X.

Take care,


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