[PATCH v5 3/5] dax: use sb_issue_zerout instead of calling dax_clear_sectors

[Verma, Vishal L]

On Sun, 2016-05-08 at 01:52 -0700, Christoph Hellwig wrote:
> On Fri, May 06, 2016 at 03:53:09PM -0600, Vishal Verma wrote:
> > 
> > From: Matthew Wilcox <matthew.r.wilcox at intel.com>
> > 
> > dax_clear_sectors() cannot handle poisoned blocks.  These must be
> > zeroed using the BIO interface instead.  Convert ext2 and XFS to
> > use
> > only sb_issue_zerout().
> > 
> > Signed-off-by: Matthew Wilcox <matthew.r.wilcox at intel.com>
> > [vishal: Also remove the dax_clear_sectors function entirely]
> > Signed-off-by: Vishal Verma <vishal.l.verma at intel.com>
> Just to make sure:  the existing sb_issue_zerout as in 4.6-rc
> is already doing the right thing for DAX?  I've got a pending
> patchset
> for XFS that introduces another dax_clear_sectors users, but if it's
> already safe to use blkdev_issue_zeroout I can switch to that and
> avoid
> the merge conflict.

I believe so - Jan has moved all unwritten extent conversions out of
DAX with his patch set, and I believe zeroing through the driver is
always fine. Ross or Jan could confirm though.