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Date:   Wed, 8 Jul 2020 08:05:05 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Keith Busch <kbusch@kernel.org>
Cc:     Baolin Wang <baolin.wang@linux.alibaba.com>, axboe@fb.com,
        hch@lst.de, sagi@grimberg.me, baolin.wang7@gmail.com,
        linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 5/5] nvme-pci: Use standard block status macro
Message-ID: <20200708060505.GA4919@lst.de>
References: <cover.1593743937.git.baolin.wang@linux.alibaba.com> <a14bca482584d912d72209c6edab6b77b1a924f2.1593743937.git.baolin.wang@linux.alibaba.com> <20200707190123.GB1997220@dhcp-10-100-145-180.wdl.wdc.com>
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On Tue, Jul 07, 2020 at 12:01:23PM -0700, Keith Busch wrote:
> On Fri, Jul 03, 2020 at 10:49:24AM +0800, Baolin Wang wrote:
> >  static blk_status_t nvme_map_data(struct nvme_dev *dev, struct request *req,
> > @@ -844,7 +844,7 @@ static blk_status_t nvme_map_metadata(struct nvme_dev *dev, struct request *req,
> >  	if (dma_mapping_error(dev->dev, iod->meta_dma))
> >  		return BLK_STS_IOERR;
> >  	cmnd->rw.metadata = cpu_to_le64(iod->meta_dma);
> > -	return 0;
> > +	return BLK_STS_OK;
> >  }
> 
> This is fine, though it takes knowing that this value is 0 for the
> subsequent 'if (!ret)' check to make sense. Maybe those should change to
> 'if (ret != BLK_STS_OK)' so the check uses the same symbol as the
> return, and will always work in the unlikely event that the defines
> are reordered.

If you think this version is inconsistent I'd rather drop this patch.
The assumption that 0 == BLK_STS_OK is inherent all over the code.