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Message-ID: <ec944a31-3edb-37fa-135e-bfcd970d8231@acm.org>
Date:   Thu, 19 May 2022 06:40:40 +0200
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Subject: Re: [PATCHv2 3/3] block: relax direct io memory alignment
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To:     Eric Biggers <ebiggers@kernel.org>, Keith Busch <kbusch@kernel.org>
Cc:     Keith Busch <kbusch@fb.com>, linux-fsdevel@vger.kernel.org,
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From:   Bart Van Assche <bvanassche@acm.org>
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On 5/19/22 05:27, Eric Biggers wrote:
> But the DMA alignment can be much lower, like 8 bytes (see nvme_set_queue_limits()).

There are block drivers that support byte alignment of block layer data 
buffers. From the iSCSI over TCP driver:

	blk_queue_dma_alignment(sdev->request_queue, 0);

Thanks,

Bart.