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Date: Tue, 20 Feb 2024 08:50:40 +0000
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Subject: Re: [PATCH v4 10/11] nvme: Atomic write support
To: Christoph Hellwig <hch@lst.de>
Cc: axboe@kernel.dk, kbusch@kernel.org, sagi@grimberg.me, jejb@linux.ibm.com,
        martin.petersen@oracle.com, djwong@kernel.org, viro@zeniv.linux.org.uk,
        brauner@kernel.org, dchinner@redhat.com, jack@suse.cz,
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        nilay@linux.ibm.com, ritesh.list@gmail.com,
        Alan Adamson <alan.adamson@oracle.com>
References: <20240219130109.341523-1-john.g.garry@oracle.com>
 <20240219130109.341523-11-john.g.garry@oracle.com>
 <20240220083119.GD13785@lst.de>
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From: John Garry <john.g.garry@oracle.com>
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On 20/02/2024 08:31, Christoph Hellwig wrote:
> 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?

NVMe does indeed have the boundary rule, but it is not really the same 
as SCSI granularity and alignment.

Anyway, I can word that statement to be clearer.

Thanks,
John