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Date:   Thu, 4 May 2023 09:24:26 +0100
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Subject: Re: [PATCH RFC 06/16] block: Limit atomic writes according to bio and
 queue limits
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To:     Keith Busch <kbusch@kernel.org>
Cc:     axboe@kernel.dk, hch@lst.de, sagi@grimberg.me,
        martin.petersen@oracle.com, djwong@kernel.org,
        viro@zeniv.linux.org.uk, brauner@kernel.org, dchinner@redhat.com,
        jejb@linux.ibm.com, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org,
        linux-scsi@vger.kernel.org, linux-xfs@vger.kernel.org,
        linux-fsdevel@vger.kernel.org,
        linux-security-module@vger.kernel.org, paul@paul-moore.com,
        jmorris@namei.org, serge@hallyn.com
References: <20230503183821.1473305-1-john.g.garry@oracle.com>
 <20230503183821.1473305-7-john.g.garry@oracle.com>
 <ZFKtt2Z5BPyV9gHJ@kbusch-mbp.dhcp.thefacebook.com>
From:   John Garry <john.g.garry@oracle.com>
Organization: Oracle Corporation
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On 03/05/2023 19:53, Keith Busch wrote:
> On Wed, May 03, 2023 at 06:38:11PM +0000, John Garry wrote:
>> +	unsigned int size = (atomic_write_max_segments - 1) *
>> +				(PAGE_SIZE / SECTOR_SIZE);
> Maybe use PAGE_SECTORS instead of recalculating it.

ok, that simplifies it a bit, but I still do have a doubt that the calc 
I use for guaranteed amount of data which can fit in a bio without ever 
requiring splitting to queue limits is correct...

Thanks,
John