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Date:   Tue, 31 May 2022 08:30:31 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Keith Busch <kbusch@kernel.org>
Cc:     Eric Biggers <ebiggers@kernel.org>, Keith Busch <kbusch@fb.com>,
        linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org,
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        bvanassche@acm.org, damien.lemoal@opensource.wdc.com,
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Subject: Re: [PATCHv4 8/9] block: relax direct io memory alignment
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On Thu, May 26, 2022 at 02:32:12PM -0600, Keith Busch wrote:
> On Thu, May 26, 2022 at 12:55:50PM -0600, Keith Busch wrote:
> > 
> > Let me see how difficult it would be catch it early in blkdev_dio_aligned().
> 
> Something like this appears to work:

This looks reasonable to me.  Nits below:

> +	if (!iov_iter_aligned(iter, bdev_dma_alignment(bdev),
> +			      bdev_logical_block_size(bdev) - 1))

This probably wants a helper so that it can also be reused by e.g.
iomap.