From: Casey Leedom <leedom@chelsio.com>
Subject: Re: DMA error when sg->offset value is greater than PAGE_SIZE in
 Intel IOMMU
Date: Wed, 27 Sep 2017 17:30:08 +0000
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Cc: Dan Williams <dan.j.williams@intel.com>,
        "Harsh Jain" <Harsh@chelsio.com>,
        "Raj, Ashok" <ashok.raj@intel.com>,
        Herbert Xu <herbert@gondor.apana.org.au>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "iommu@lists.linux-foundation.org" <iommu@lists.linux-foundation.org>,
        "linux-crypto@vger.kernel.org" <linux-crypto@vger.kernel.org>,
        "dwmw2@infradead.org" <dwmw2@infradead.org>,
        Michael Werner <werner@chelsio.com>, "nd@arm.com" <nd@arm.com>
To: Robin Murphy <robin.murphy@arm.com>
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| From: Robin Murphy <robin.murphy@arm.com>
| Sent: Wednesday, September 27, 2017 10:18 AM
|=20
| From my experience, in general terms each scatterlist segment
| represents some contiguous quantity of pages, of which sg->page is the
| first, while sg->length and sg->offset describe the specific bounds of
| that segment's data. ...

  Okay, thanks Robin.  That'll help me in my reviews of your and Ashok's
suggested changes to the Intel I/O MMU __domain_mapping() routine.

Casey=