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Date: Thu, 11 Apr 2024 09:15:04 +0100
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Subject: Re: [PATCH v6 05/10] block: Add core atomic write support
To: Luis Chamberlain <mcgrof@kernel.org>, Randy Dunlap <rdunlap@infradead.org>
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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        nilay@linux.ibm.com, ritesh.list@gmail.com, willy@infradead.org,
        Himanshu Madhani <himanshu.madhani@oracle.com>
References: <20240326133813.3224593-1-john.g.garry@oracle.com>
 <20240326133813.3224593-6-john.g.garry@oracle.com>
 <0a9fb564-7129-4153-97d6-76e9b3a1b6c1@infradead.org>
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From: John Garry <john.g.garry@oracle.com>
Organization: Oracle Corporation
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On 11/04/2024 00:34, Luis Chamberlain wrote:
>> On 3/26/24 06:38, John Garry wrote:
>>> diff --git a/Documentation/ABI/stable/sysfs-block b/Documentation/ABI/stable/sysfs-block
>>> index 1fe9a553c37b..4c775f4bdefe 100644
>>> --- a/Documentation/ABI/stable/sysfs-block
>>> +++ b/Documentation/ABI/stable/sysfs-block
>>> +What:		/sys/block/<disk>/atomic_write_boundary_bytes
>>> +Date:		February 2024
>>> +Contact:	Himanshu Madhani<himanshu.madhani@oracle.com>
>>> +Description:
>>> +		[RO] A device may need to internally split I/Os which
>>> +		straddle a given logical block address boundary. In that
>>> +		case a single atomic write operation will be processed as
>>> +		one of more sub-operations which each complete atomically.
>> 		    or
> If*or*  was meant, wouldn't it be better just to say one or more
> operations may be processed as one atomically in this situation?

"Or" was meant (thanks Randy).

I think that we just need to say that the write operation will not 
complete atomically if it straddles the boundary. Whether the separate 
parts of the write operation which straddle the boundary complete 
atomically is undefined and irrelevant.

Thanks,
John