From: Steven Whitehouse <swhiteho@redhat.com>
To: tytso@mit.edu
Cc: Andreas Dilger <adilger@sun.com>,
linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: Motion to nuke FS_DIRECTIO_FL
Date: Mon, 25 Jan 2010 09:31:27 +0000 [thread overview]
Message-ID: <1264411887.2449.3.camel@localhost> (raw)
In-Reply-To: <20100125080610.GD4372@thunk.org>
Hi,
On Mon, 2010-01-25 at 03:06 -0500, tytso@mit.edu wrote:
> On Sun, Jan 24, 2010 at 11:18:47PM -0700, Andreas Dilger wrote:
> >
> > It doesn't seem that ext2/3/4 are using the 0x00100000 value itself,
> > but it seems the VFS is using this value for FS_DIRECTIO_FL. Should
> > we reserve this in the ext4 flags also, to avoid collisions? I'm
> > not sure what that flag is for, possibly to force all IO to the file
> > to be uncached?
>
> Hmm, absolutely nothing seems to use FS_DIRECTIO_FL; it looks like it
> was introduced by GFS2 in commit 128e5eba in 2006 and then dropped in
> commit c9f6a6bb in 2008, but we never killed the FS_DIRECTIO_FL flag
> itself in include/linux/fs.h.
>
> The summary line for c9f6a6bb is a bit amusing:
>
> [GFS2] Remove support for unused and pointless flag
>
> Heh.
>
> Sounds like we should just kill it. Any objections?
>
> - Ted
No. Sounds good to me. It was never used with GFS2 and it a left-over
from GFS1 which had a flag allowing all "normal" I/O to be turned into
O_DIRECT I/O depending on an inode flag. The idea failed due to
alignment restrictions of course and nobody actually used it,
Steve.
prev parent reply other threads:[~2010-01-25 9:28 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20090906092546.GU4197@webber.adilger.int>
[not found] ` <20100124194839.GB4372@thunk.org>
[not found] ` <E1520682-CD9F-445E-AF33-D5FCDABA1FF8@sun.com>
2010-01-25 8:06 ` Motion to nuke FS_DIRECTIO_FL tytso
2010-01-25 9:31 ` Steven Whitehouse [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=1264411887.2449.3.camel@localhost \
--to=swhiteho@redhat.com \
--cc=adilger@sun.com \
--cc=linux-ext4@vger.kernel.org \
--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).