linux-fsdevel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Joel Becker <Joel.Becker@oracle.com>
To: Theodore Tso <tytso@mit.edu>,
	Christoph Hellwig <hch@infradead.org>,
	Jamie Lokier <jamie@shareable.org>,
	Jens Axboe <jens.axboe@oracle.com>,
	linux-fsdevel@vger.kernel.org, linux-scsi
Subject: Re: O_DIRECT and barriers
Date: Fri, 21 Aug 2009 15:45:18 -0700	[thread overview]
Message-ID: <20090821224518.GG4330@mail.oracle.com> (raw)
In-Reply-To: <20090821220852.GM9529@mit.edu>

On Fri, Aug 21, 2009 at 06:08:52PM -0400, Theodore Tso wrote:
> http://ext4.wiki.kernel.org/index.php/Clarifying_Direct_IO's_Semantics
> 
> Comments are welcome, either on the wiki's talk page, or directly to
> me, or to the linux-fsdevel or linux-ext4.

	In the section on perhaps not waiting for buffered fallback, we
need to clarify that O_DIRECT reads need to know to look in the
pagecache.  That is, if we decide that extending O_DIRECT writes without
fsync can return before the data hits the storage, the caller shouldn't
also have to call fsync() just to call read() of data they just wrote!

Joel

-- 

To spot the expert, pick the one who predicts the job will take the
longest and cost the most.

Joel Becker
Principal Software Developer
Oracle
E-mail: joel.becker@oracle.com
Phone: (650) 506-8127

  parent reply	other threads:[~2009-08-21 22:45 UTC|newest]

Thread overview: 50+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <1250697884-22288-1-git-send-email-jack@suse.cz>
2009-08-20 22:12 ` O_DIRECT and barriers Christoph Hellwig
2009-08-21 11:40   ` Jens Axboe
2009-08-21 13:54     ` Jamie Lokier
2009-08-21 14:26       ` Christoph Hellwig
2009-08-21 15:24         ` Jamie Lokier
2009-08-21 17:45           ` Christoph Hellwig
2009-08-21 19:18             ` Ric Wheeler
2009-08-22  0:50             ` Jamie Lokier
2009-08-22  2:19               ` Theodore Tso
2009-08-22  2:31                 ` Theodore Tso
2009-08-24  2:34               ` Christoph Hellwig
2009-08-27 14:34                 ` Jamie Lokier
2009-08-27 17:10                   ` adding proper O_SYNC/O_DSYNC, was " Christoph Hellwig
2009-08-27 17:24                     ` Ulrich Drepper
2009-08-28 15:46                       ` Christoph Hellwig
2009-08-28 16:06                         ` Ulrich Drepper
2009-08-28 16:17                           ` Christoph Hellwig
2009-08-28 16:33                             ` Ulrich Drepper
2009-08-28 16:41                               ` Christoph Hellwig
2009-08-28 20:51                                 ` Ulrich Drepper
2009-08-28 21:08                                   ` Christoph Hellwig
2009-08-28 21:16                                     ` Trond Myklebust
2009-08-28 21:29                                       ` Christoph Hellwig
2009-08-28 21:43                                         ` Trond Myklebust
2009-08-28 22:39                                           ` Christoph Hellwig
2009-08-30 16:44                                     ` Jamie Lokier
2009-08-28 16:46                               ` Jamie Lokier
2009-08-29  0:59                                 ` Jamie Lokier
2009-08-28 16:44                         ` Jamie Lokier
2009-08-28 16:50                           ` Jamie Lokier
2009-08-28 21:08                           ` Ulrich Drepper
2009-08-30 16:58                             ` Jamie Lokier
2009-08-30 17:48                             ` Jamie Lokier
2009-08-28 23:06                         ` Jamie Lokier
2009-08-28 23:46                           ` Christoph Hellwig
2009-08-21 22:08         ` Theodore Tso
2009-08-21 22:38           ` Joel Becker
2009-08-21 22:45           ` Joel Becker [this message]
2009-08-22  2:11             ` Theodore Tso
2009-08-24  2:42               ` Christoph Hellwig
2009-08-24  2:37             ` Christoph Hellwig
2009-08-22  0:56           ` Jamie Lokier
2009-08-22  2:06             ` Theodore Tso
2009-08-26  6:34           ` Dave Chinner
2009-08-26 15:01             ` Jamie Lokier
2009-08-26 18:47               ` Theodore Tso
2009-08-27 14:50                 ` Jamie Lokier
2009-08-21 14:20     ` Christoph Hellwig
2009-08-21 15:06       ` James Bottomley
2009-08-21 15:23         ` Christoph Hellwig

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=20090821224518.GG4330@mail.oracle.com \
    --to=joel.becker@oracle.com \
    --cc=hch@infradead.org \
    --cc=jamie@shareable.org \
    --cc=jens.axboe@oracle.com \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=tytso@mit.edu \
    /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;
as well as URLs for NNTP newsgroup(s).