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Subject: RE: [PATCH] scsi: ufshpb: Properly handle max-single-cmd
Reply-To: daejun7.park@samsung.com
Sender: Daejun Park <daejun7.park@samsung.com>
From:   Daejun Park <daejun7.park@samsung.com>
To:     Avri Altman <avri.altman@wdc.com>,
        "James E . J . Bottomley" <jejb@linux.vnet.ibm.com>,
        "Martin K . Petersen" <martin.petersen@oracle.com>
CC:     "linux-scsi@vger.kernel.org" <linux-scsi@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Bart Van Assche <bvanassche@acm.org>,
        Adrian Hunter <adrian.hunter@intel.com>,
        Bean Huo <beanhuo@micron.com>,
        Daejun Park <daejun7.park@samsung.com>
In-Reply-To: <20211031123654.17719-1-avri.altman@wdc.com>
Message-ID: <1891546521.01635752701431.JavaMail.epsvc@epcpadp3>
Date:   Mon, 01 Nov 2021 16:22:58 +0900
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References: <20211031123654.17719-1-avri.altman@wdc.com>
        <CGME20211031123708epcas2p16645db36a077acf3bd6c0138e50fedc8@epcms2p7>
Precedence: bulk

Hi Avri,

> The spec recommends that for transfer length larger than the
> max-single-cmd attribute (bMAX_ DATA_SIZE_FOR_HPB_SINGLE_CMD) it is
> possible to couple pre-reqs with the HPB-READ command.  Being a
> recommendation, using pre-reqs can be perceived merely as a mean of
> optimization.  A common practice was to send pre-reqs for chunks within
> some interval, and leave the READ10 untouched if larger.
>  
> Anyway, now that the pre-reqs flows have been opt-out, all the commands
> are single commands.  So properly handle this attribute and do not send
> HPB-READ for transfer lengths larger than max-single-cmd.
>  
> Fixes: 09d9e4d04187 (scsi: ufs: ufshpb: Remove HPB2.0 flows)
>  
> Signed-off-by: Avri Altman <avri.altman@wdc.com>
> ---
>  drivers/scsi/ufs/ufshpb.c | 29 +++++++++++++++--------------
>  drivers/scsi/ufs/ufshpb.h |  1 -
>  2 files changed, 15 insertions(+), 15 deletions(-)

Reviewed-by: Daejun Park <daejun7.park@samsung.com>