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Date:   Sun, 15 May 2022 23:52:46 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Keith Busch <kbusch@fb.com>
Cc:     linux-block@vger.kernel.org, axboe@kernel.dk,
        Kernel Team <kernel-team@fb.com>,
        Keith Busch <kbusch@kernel.org>
Subject: Re: [PATCH 1/3] block: export dma_alignment attribute
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I'm not against the sysfs file, but for applications this is a
horrible interface.  We really need something that works on the fd.

The XFS_IOC_DIOINFO ioctl from xfs is one, although ugly, option.
The other is to export the alignment requirements through statx.
We had that whole discussion with the inline crypto direct I/O support,
and we really need to tackle it rather sooner than later.