LKML Archive on lore.kernel.org
 help / color / Atom feed
From: Ira Weiny <ira.weiny@intel.com>
To: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: linux-kernel@vger.kernel.org, linux-xfs@vger.kernel.org,
	Al Viro <viro@zeniv.linux.org.uk>, Jan Kara <jack@suse.cz>,
	Dan Williams <dan.j.williams@intel.com>,
	Dave Chinner <david@fromorbit.com>,
	Christoph Hellwig <hch@lst.de>,
	"Theodore Y. Ts'o" <tytso@mit.edu>,
	Jeff Moyer <jmoyer@redhat.com>,
	linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org,
	linux-api@vger.kernel.org
Subject: Re: [PATCH V11 11/11] fs/xfs: Update xfs_ioctl_setattr_dax_invalidate()
Date: Tue, 2 Jun 2020 16:15:10 -0700
Message-ID: <20200602231510.GH1505637@iweiny-DESK2.sc.intel.com> (raw)
In-Reply-To: <20200602172353.GC8230@magnolia>

On Tue, Jun 02, 2020 at 10:23:53AM -0700, Darrick J. Wong wrote:
> On Tue, Apr 28, 2020 at 01:11:38PM -0700, Darrick J. Wong wrote:
> > On Mon, Apr 27, 2020 at 05:21:42PM -0700, ira.weiny@intel.com wrote:
> > > From: Ira Weiny <ira.weiny@intel.com>
> > > 

...

> > > -out_unlock:
> > > -	xfs_iunlock(ip, XFS_MMAPLOCK_EXCL | XFS_IOLOCK_EXCL);
> > > -	return error;
> > > +	if ((mp->m_flags & XFS_MOUNT_DAX_ALWAYS) ||
> > > +	    (mp->m_flags & XFS_MOUNT_DAX_NEVER))
> > > +		return;
> > >  
> > > +	if (((fa->fsx_xflags & FS_XFLAG_DAX) &&
> > > +	    !(ip->i_d.di_flags2 & XFS_DIFLAG2_DAX)) ||
> > > +	    (!(fa->fsx_xflags & FS_XFLAG_DAX) &&
> > > +	     (ip->i_d.di_flags2 & XFS_DIFLAG2_DAX)))
> > > +		d_mark_dontcache(inode);
> 
> Now that I think about this further, are we /really/ sure that we want
> to let unprivileged userspace cause inode evictions?

This code only applies to files they have access to.  And it does not directly
cause an eviction.  It only hints that those inodes (for which they have access
to) will not be cached thus causing them to be reloaded sooner than they might
otherwise be.

So I think we are fine here.

Ira

> 
> --D
> 

  reply index

Thread overview: 29+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-04-28  0:21 [PATCH V11 00/11] XFS - Enable per-file/per-directory DAX operations V11 ira.weiny
2020-04-28  0:21 ` [PATCH V11 01/11] fs/xfs: Remove unnecessary initialization of i_rwsem ira.weiny
2020-04-28  0:21 ` [PATCH V11 02/11] fs: Remove unneeded IS_DAX() check in io_is_direct() ira.weiny
2020-04-28  0:21 ` [PATCH V11 03/11] fs/stat: Define DAX statx attribute ira.weiny
2020-04-28  0:21 ` [PATCH V11 04/11] Documentation/dax: Update Usage section ira.weiny
2020-04-28 20:27   ` Darrick J. Wong
2020-04-28 20:53     ` Ira Weiny
2020-04-28 21:12       ` Darrick J. Wong
2020-04-28 22:21   ` [PATCH V11.1] " ira.weiny
2020-04-29  2:21     ` Randy Dunlap
2020-04-29  4:30       ` Ira Weiny
2020-04-29  4:33     ` [PATCH V11.2] " ira.weiny
2020-04-29  5:47       ` Randy Dunlap
2020-04-28  0:21 ` [PATCH V11 05/11] fs/xfs: Change XFS_MOUNT_DAX to XFS_MOUNT_DAX_ALWAYS ira.weiny
2020-04-28  0:21 ` [PATCH V11 06/11] fs/xfs: Make DAX mount option a tri-state ira.weiny
2020-04-28 20:08   ` Darrick J. Wong
2020-04-28  0:21 ` [PATCH V11 07/11] fs/xfs: Create function xfs_inode_should_enable_dax() ira.weiny
2020-04-28  0:21 ` [PATCH V11 08/11] fs/xfs: Combine xfs_diflags_to_linux() and xfs_diflags_to_iflags() ira.weiny
2020-04-28  0:21 ` [PATCH V11 09/11] fs: Lift XFS_IDONTCACHE to the VFS layer ira.weiny
2020-04-28 20:06   ` Darrick J. Wong
2020-04-28  0:21 ` [PATCH V11 10/11] fs: Introduce DCACHE_DONTCACHE ira.weiny
2020-04-28 13:04   ` Jan Kara
2020-04-28 20:09   ` Darrick J. Wong
2020-04-28  0:21 ` [PATCH V11 11/11] fs/xfs: Update xfs_ioctl_setattr_dax_invalidate() ira.weiny
2020-04-28 20:11   ` Darrick J. Wong
2020-06-02 17:23     ` Darrick J. Wong
2020-06-02 23:15       ` Ira Weiny [this message]
2020-06-03 10:10       ` Jan Kara
2020-06-03 17:03         ` Darrick J. Wong

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=20200602231510.GH1505637@iweiny-DESK2.sc.intel.com \
    --to=ira.weiny@intel.com \
    --cc=dan.j.williams@intel.com \
    --cc=darrick.wong@oracle.com \
    --cc=david@fromorbit.com \
    --cc=hch@lst.de \
    --cc=jack@suse.cz \
    --cc=jmoyer@redhat.com \
    --cc=linux-api@vger.kernel.org \
    --cc=linux-ext4@vger.kernel.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-xfs@vger.kernel.org \
    --cc=tytso@mit.edu \
    --cc=viro@zeniv.linux.org.uk \
    /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

LKML Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/lkml/0 lkml/git/0.git
	git clone --mirror https://lore.kernel.org/lkml/1 lkml/git/1.git
	git clone --mirror https://lore.kernel.org/lkml/2 lkml/git/2.git
	git clone --mirror https://lore.kernel.org/lkml/3 lkml/git/3.git
	git clone --mirror https://lore.kernel.org/lkml/4 lkml/git/4.git
	git clone --mirror https://lore.kernel.org/lkml/5 lkml/git/5.git
	git clone --mirror https://lore.kernel.org/lkml/6 lkml/git/6.git
	git clone --mirror https://lore.kernel.org/lkml/7 lkml/git/7.git
	git clone --mirror https://lore.kernel.org/lkml/8 lkml/git/8.git
	git clone --mirror https://lore.kernel.org/lkml/9 lkml/git/9.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 lkml lkml/ https://lore.kernel.org/lkml \
		linux-kernel@vger.kernel.org
	public-inbox-index lkml

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-kernel


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git