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Date:   Fri, 15 Jun 2018 13:58:19 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Ming Lei <tom.leiming@gmail.com>
Cc:     "jianchao.wang" <jianchao.w.wang@oracle.com>,
        Jens Axboe <axboe@kernel.dk>, Christoph Hellwig <hch@lst.de>,
        James Bottomley <jejb@linux.vnet.ibm.com>,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
        linux-block <linux-block@vger.kernel.org>,
        Linux SCSI List <linux-scsi@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 1/2] block: export __blk_complete_request
Message-ID: <20180615115819.GA25694@lst.de>
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On Fri, Jun 15, 2018 at 11:20:40AM +0800, Ming Lei wrote:
> > but blk_mq_check_expired doesn't do that.
> > do I miss anything ?
> 
> Right, that is the difference between blk-mq and legacy now, then if scsi-mq
> drivers can work well, they should work well with the following change in the
> non-mq mode:

We'll still need referene counting against reuse and/or premature
freeing of requests.