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From: Shaun Tancheff <shaun.tancheff@seagate.com>
Date: Tue, 23 Aug 2016 01:20:28 -0500
Message-ID: <CAJVOszD8HDqQMxyAnU=Yh6UDA+KE13u7Mq6s248uguRf-uUkYg@mail.gmail.com>
Subject: Re: [PATCH v6 1/4] libata: Safely overwrite attached page in WRITE
 SAME xlat
To: Tom Yan <tom.ty89@gmail.com>
Cc: Shaun Tancheff <shaun@tancheff.com>, linux-ide@vger.kernel.org,
        LKML <linux-kernel@vger.kernel.org>, Tejun Heo <tj@kernel.org>,
        Christoph Hellwig <hch@lst.de>,
        "Martin K . Petersen" <martin.petersen@oracle.com>,
        Damien Le Moal <damien.lemoal@hgst.com>,
        Hannes Reinecke <hare@suse.de>,
        Josh Bingaman <josh.bingaman@seagate.com>,
        Hannes Reinecke <hare@suse.com>
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On Tue, Aug 23, 2016 at 12:26 AM, Tom Yan <tom.ty89@gmail.com> wrote:

> It is always 1 merely because we prefer sticking to that. Say we want
> to enable multi-block payload now, it won't be 1 anymore.

Sorry, I though that DSM TRIM is using 512 bytes here because
WRITE_SAME_16 has a payload of a single logical sector.

> Also note that the payload is NOT always fully-filled.

Oh, I was considering filling the remainder of the buffer
with 0's using memset() as you described to be "filly-filled"
in this case. Sorry for the confusion.

-- 
Shaun Tancheff