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Date:   Tue, 14 Jun 2022 10:29:16 +0100
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Subject: Re: [PATCH RFC v2 01/18] blk-mq: Add a flag for reserved requests
To:     Christoph Hellwig <hch@lst.de>
CC:     <axboe@kernel.dk>, <damien.lemoal@opensource.wdc.com>,
        <jejb@linux.ibm.com>, <martin.petersen@oracle.com>,
        <brking@us.ibm.com>, <hare@suse.de>, <linux-block@vger.kernel.org>,
        <linux-ide@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <linux-scsi@vger.kernel.org>, <chenxiang66@hisilicon.com>
References: <1654770559-101375-1-git-send-email-john.garry@huawei.com>
 <1654770559-101375-2-git-send-email-john.garry@huawei.com>
 <20220614064303.GA31683@lst.de>
From:   John Garry <john.garry@huawei.com>
In-Reply-To: <20220614064303.GA31683@lst.de>
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On 14/06/2022 07:43, Christoph Hellwig wrote:
> On Thu, Jun 09, 2022 at 06:29:02PM +0800, John Garry wrote:
>> Add a flag for reserved requests so that drivers may know this for any
>> special handling.
>>
>> The 'reserved' argument in blk_mq_ops.timeout callback could now be
>> replaced by using this flag.
> And we should probably do that ASAP, independent of the rest of this
> series. 

We only have 2x users of the 'reserved' arg for 11x implementations of 
blk_mq_ops.timeout:
- mtip32xx.c
- scsi_lib.c

scsi_lib.c is dubious as currently scsi does use reserved commands. So 
we really only have 1x.

I'd be happy to take any spin-off series to make this one more 
manageable, but is just removing an arg a strong enough reason for that? 
That reserved arg is passed around a lot in the blk-mq iter functions, 
so probably yes.

> Otherwise looks good:
> 
> Reviewed-by: Christoph Hellwig<hch@lst.de>

Thanks