Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
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>,
        Dave Jiang <dave.jiang@intel.com>,
        Alasdair Kergon <agk@redhat.com>,
        Mike Snitzer <snitzer@redhat.com>,
        device-mapper development <dm-devel@redhat.com>,
        "Weiny, Ira" <ira.weiny@intel.com>,
        Matthew Wilcox <willy@infradead.org>,
        Vivek Goyal <vgoyal@redhat.com>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        Linux NVDIMM <nvdimm@lists.linux.dev>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-xfs <linux-xfs@vger.kernel.org>, X86 ML <x86@kernel.org>
Subject: Re: [PATCH v7 4/6] dax: add DAX_RECOVERY flag and .recovery_write
 dev_pgmap_ops
Message-ID: <YlUH2f66hMyXOP1r@infradead.org>
References: <20220405194747.2386619-1-jane.chu@oracle.com>
 <20220405194747.2386619-5-jane.chu@oracle.com>
 <CAPcyv4jpOss6hzPgM913v_QsZ+PB6Jzo1WV=YdUvnKZiwtfjiA@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <CAPcyv4jpOss6hzPgM913v_QsZ+PB6Jzo1WV=YdUvnKZiwtfjiA@mail.gmail.com>
Precedence: bulk

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.