public inbox for linux-xfs@vger.kernel.org
 help / color / mirror / Atom feed
From: Christoph Hellwig <hch@infradead.org>
To: Arkadiusz Miskiewicz <arekm@maven.pl>
Cc: xfs@oss.sgi.com
Subject: Re: separate project quota from group quota (questions, design issues)
Date: Sat, 4 Sep 2010 19:30:53 -0400	[thread overview]
Message-ID: <20100904233053.GA26586@infradead.org> (raw)
In-Reply-To: <201009041000.55878.arekm@maven.pl>

Thanks for doing this work Arek, I think it will be useful for some
users and defintively is cleaners than what we have now.

> I started doing that by splitting every group+project handling code into 
> separate group and project one. Added superblock field for project quota. New 
> feature flag (SEPARATEPQUOTA).

Ok.

> If old filesystem (for SEPARATEQUOTA) is mounted then I'll simply load 
> sb_gquotino into mp->m_sb.sb_pquotino which I think is enough to handle old fs 
> (since new kernel operates on separate structures for project quota).

Do you mean an old filesystem without the SEPARATEQUOTA bit set here?

> New filesystem (without quota inodes allocated yet), when mounted, gets new 
> quota inode allocated for project quota and SEPARATEQUOTA feature bit set.

I think we need the SEPARATEQUOTA bit set explicitly by
mkfs.xfs/xfs_admin.  But once we start using project quotas with the
bit set the above sounds fine.

> Converting old fs to separate quota isn't currently solved. User could need 
> two choices - use old group quota still as group or old group as new project 
> quota. Not sure how to handle these yet. 

We know what sb_gquotino is used for currently from sb_qflags.  If it's
used for group quota we can simply set the SEPARATEQUOTA bit and we're
done.  To convert a filesystem using project quotas to SEPARATEQUOTA
sb_gquotino needs to be cleared and instead the new sb_pquotino field
needs to point to the project quota inode.


Need to go now, I'll answer to your other questions once I had some more
time to review them.

_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs

  parent reply	other threads:[~2010-09-04 23:30 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-09-04  8:00 separate project quota from group quota (questions, design issues) Arkadiusz Miskiewicz
2010-09-04 17:13 ` Michael Monnerie
2010-09-04 23:30 ` Christoph Hellwig [this message]
2010-09-05 17:24   ` Arkadiusz Miskiewicz
2010-09-06  1:12     ` Dave Chinner
2010-09-06  6:28       ` Arkadiusz Miskiewicz
2010-09-06  1:16   ` Dave Chinner

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20100904233053.GA26586@infradead.org \
    --to=hch@infradead.org \
    --cc=arekm@maven.pl \
    --cc=xfs@oss.sgi.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox