public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Andrew Morton <akpm@zip.com.au>
To: Christoph Hellwig <hch@infradead.org>
Cc: Christoph Hellwig <hch@lst.de>,
	marcelo@conectiva.com.br, linux-kernel@vger.kernel.org,
	"Stephen C. Tweedie" <sct@redhat.com>,
	Joe Thornber <joe@fib011235813.fsnet.co.uk>
Subject: Re: [PATCH] simplify b_inode usage
Date: Fri, 16 Aug 2002 07:22:48 -0700	[thread overview]
Message-ID: <3D5D0AB8.1A343AE@zip.com.au> (raw)
In-Reply-To: 20020816133654.A17193@infradead.org

Christoph Hellwig wrote:
> 
> ...
> > Also, Joe Thornber needs to add another pointer to struct buffer_head
> > for LVM2 reasons.  If we collapse b_inode into a b_flags bit then
> > Joe gets his pointer for free (bh stays at 48 bytes on ia32).
> 
> We also need to make b_size an 32 bit quantity, otherwise 64k buffers
> on architectures like ia64 will get us horrible overflows.  And yes,
> people use that big pages - Nathan just added an ugly workaround to XFS,
> for splitting 64k pages into multiple bh, because of that exactly that
> limitation.

OK.  We'd need to prevent that from taking bh beyond the current 96 bytes.
The hashed wakeups, perhaps.

> >
> > So I'd suggest you just go ahead and do it that way.  (I had a patch
> > for that but seem to have misplaced it).
> 
> As the patch is already large enough I'd be happy if Marcelo applies the
> current patch, once it's in I'll move the indicator to b_flags, okay?

Yup.

      reply	other threads:[~2002-08-16 14:08 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2002-08-13 15:10 [PATCH] simplify b_inode usage Christoph Hellwig
2002-08-13 21:10 ` Andrew Morton
2002-08-14  7:43   ` Joe Thornber
2002-08-16 12:36   ` Christoph Hellwig
2002-08-16 14:22     ` Andrew Morton [this message]

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=3D5D0AB8.1A343AE@zip.com.au \
    --to=akpm@zip.com.au \
    --cc=hch@infradead.org \
    --cc=hch@lst.de \
    --cc=joe@fib011235813.fsnet.co.uk \
    --cc=linux-kernel@vger.kernel.org \
    --cc=marcelo@conectiva.com.br \
    --cc=sct@redhat.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