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Date:   Tue, 9 Apr 2019 15:59:24 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     David Woodhouse <dwmw2@infradead.org>,
        Joerg Roedel <joro@8bytes.org>
Cc:     iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org
Subject: per-device dma_map_ops for intel-iommu?
Message-ID: <20190409135924.GA11431@lst.de>
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Hi David and Joerg,

do you remember a good reason why intel-iommu is not using per-device
dma_map_ops like the AMD iommu or the various ARM iommus?

Right now intel-iommu.c contains a half-asses reimplementation of the
dma direct code for the iommu_no_mapping() case, and it would seem
much nicer to just fall back to that case and not even call into
intel-iommu in that case.