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Date:   Mon, 14 Jan 2019 10:46:14 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     Shiraz Saleem <shiraz.saleem@intel.com>
Cc:     Jason Gunthorpe <jgg@mellanox.com>,
        "linux-rdma@vger.kernel.org" <linux-rdma@vger.kernel.org>,
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        Yong Zhi <yong.zhi@intel.com>,
        Sakari Ailus <sakari.ailus@linux.intel.com>,
        Bingbu Cao <bingbu.cao@intel.com>,
        Tian Shu Qiu <tian.shu.qiu@intel.com>,
        Jian Xu Zheng <jian.xu.zheng@intel.com>,
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        Thomas Hellstrom <thellstrom@vmware.com>,
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Subject: Re: [PATCH] lib/scatterlist: Provide a DMA page iterator
Message-ID: <20190114094614.GA29604@lst.de>
References: <20190104223531.GA1705@ziepe.ca> <20190112182704.GA15320@ssaleem-MOBL4.amr.corp.intel.com> <20190112183752.GC16457@mellanox.com> <20190112190305.GA19436@ssaleem-MOBL4.amr.corp.intel.com>
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On Sat, Jan 12, 2019 at 01:03:05PM -0600, Shiraz Saleem wrote:
> Well I was trying convert the RDMA drivers to use your new iterator variant
> and saw the need for it in locations where we need virtual address of the pages
> contained in the SGEs.

As far as i can tell that pg_arr[i] value is only ever used for
the case where we do an explicit dma coherent allocation,  so you
should not have to fill it out at all.