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From:   Christoph Hellwig <hch@lst.de>
To:     Jonas Bonn <jonas@southpole.se>,
        Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>,
        Stafford Horne <shorne@gmail.com>
Cc:     Marek Szyprowski <m.szyprowski@samsung.com>,
        Robin Murphy <robin.murphy@arm.com>,
        Will Deacon <will@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        openrisc@lists.librecores.org, iommu@lists.linux-foundation.org,
        linux-arm-kernel@lists.infradead.org, linux-arch@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: provide in-place uncached remapping for dma-direct (resend)
Date:   Thu, 20 Feb 2020 09:01:37 -0800
Message-Id: <20200220170139.387354-1-hch@lst.de>
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Hi all,

this series provides support for remapping places uncached in-place in
the generic dma-direct code, and moves openrisc over from its own
in-place remapping scheme.  The arm64 folks also had interest in such
a scheme to avoid problems with speculating into cache aliases.

Also all architectures that always use small page mappings for the
kernel and have non-coherent DMA should look into enabling this
scheme, as it is much more efficient than the vmap remapping.