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Date: Mon, 11 Apr 2022 22:02:17 -0700
From: Christoph Hellwig <hch@infradead.org>
To: Dan Williams <dan.j.williams@intel.com>
Cc: Jane Chu <jane.chu@oracle.com>, david <david@fromorbit.com>,
	"Darrick J. Wong" <djwong@kernel.org>,
	Christoph Hellwig <hch@infradead.org>,
	Vishal L Verma <vishal.l.verma@intel.com>,
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	Mike Snitzer <snitzer@redhat.com>,
	device-mapper development <dm-devel@redhat.com>,
	"Weiny, Ira" <ira.weiny@intel.com>,
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Subject: Re: [PATCH v7 4/6] dax: add DAX_RECOVERY flag and .recovery_write
 dev_pgmap_ops
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On Mon, Apr 11, 2022 at 09:57:36PM -0700, Dan Williams wrote:
> So how about change 'int flags' to 'enum dax_access_mode mode' where
> dax_access_mode is:
> 
> /**
>  * enum dax_access_mode - operational mode for dax_direct_access()
>  * @DAX_ACCESS: nominal access, fail / trim access on encountering poison
>  * @DAX_RECOVERY_WRITE: ignore poison and provide a pointer suitable
> for use with dax_recovery_write()
>  */
> enum dax_access_mode {
>     DAX_ACCESS,
>     DAX_RECOVERY_WRITE,
> };
> 
> Then the conversions look like this:
> 
>  -       rc = dax_direct_access(iter->iomap.dax_dev, pgoff, 1, &kaddr, NULL);
>  +       rc = dax_direct_access(iter->iomap.dax_dev, pgoff, 1,
> DAX_ACCESS, &kaddr, NULL);
> 
> ...and there's less chance of confusion with the @nr_pages argument.

Yes, this might be a little nicer.