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Date: Tue, 20 Feb 2024 09:31:19 +0100
From: Christoph Hellwig <hch@lst.de>
To: John Garry <john.g.garry@oracle.com>
Cc: axboe@kernel.dk, kbusch@kernel.org, hch@lst.de, sagi@grimberg.me,
	jejb@linux.ibm.com, martin.petersen@oracle.com, djwong@kernel.org,
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	linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org,
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	io-uring@vger.kernel.org, nilay@linux.ibm.com,
	ritesh.list@gmail.com, Alan Adamson <alan.adamson@oracle.com>
Subject: Re: [PATCH v4 10/11] nvme: Atomic write support
Message-ID: <20240220083119.GD13785@lst.de>
References: <20240219130109.341523-1-john.g.garry@oracle.com> <20240219130109.341523-11-john.g.garry@oracle.com>
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User-Agent: Mutt/1.5.17 (2007-11-01)

Thanks for writing a good commit message!

> NVMe namespaces may define an atomic boundary, whereby no atomic guarantees
> are provided for a write which straddles this per-lba space boundary. The
> block layer merging policy is such that no merges may occur in which the
> resultant request would straddle such a boundary.
> 
> Unlike SCSI, NVMe specifies no granularity or alignment rules.

Well, the boundary really is sort of a granularity and alignment,
isn't it?