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* dma-mapping: consolidate the dma mmap implementationsChristoph Hellwig2018-09-201-11/+0
| | | | | | | | | | | | | | | | | The only functional differences (modulo a few missing fixes in the arch code) is that architectures without coherent caches need a hook to convert a virtual or dma address into a pfn, given that we don't have the kernel linear mapping available for the otherwise easy virt_to_page call. As a side effect we can support mmap of the per-device coherent area even on architectures not providing the callback, and we make previous dangerous default methods dma_common_mmap actually save for non-coherent architectures by rejecting it without the right helper. In addition to that we need a hook so that some architectures can override the protection bits when mmaping a dma coherent allocations. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Paul Burton <paul.burton@mips.com> # MIPS parts
* dma-mapping: merge direct and noncoherent opsChristoph Hellwig2018-09-201-6/+115
| | | | | | | | | All the cache maintainance is already stubbed out when not enabled, but merging the two allows us to nicely handle the case where cache maintainance is required for some devices, but not others. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Paul Burton <paul.burton@mips.com> # MIPS parts
* kernel/dma/direct: take DMA offset into account in dma_direct_supportedChristoph Hellwig2018-09-011-2/+2
| | | | | | | | | | When a device has a DMA offset the dma capable result will change due to the difference between the physical and DMA address. Take that into account. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by: Robin Murphy <robin.murphy@arm.com>
* kernel/dma: remove unsupported gfp_mask parameter from ↵Marek Szyprowski2018-08-171-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | dma_alloc_from_contiguous() The CMA memory allocator doesn't support standard gfp flags for memory allocation, so there is no point having it as a parameter for dma_alloc_from_contiguous() function. Replace it by a boolean no_warn argument, which covers all the underlaying cma_alloc() function supports. This will help to avoid giving false feeling that this function supports standard gfp flags and callers can pass __GFP_ZERO to get zeroed buffer, what has already been an issue: see commit dd65a941f6ba ("arm64: dma-mapping: clear buffers allocated with FORCE_CONTIGUOUS flag"). Link: http://lkml.kernel.org/r/20180709122020eucas1p21a71b092975cb4a3b9954ffc63f699d1~-sqUFoa-h2939329393eucas1p2Y@eucas1p2.samsung.com Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Acked-by: Michał Nazarewicz <mina86@mina86.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Laura Abbott <labbott@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Joonsoo Kim <js1304@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* dma-mapping: Generalise dma_32bit_limit flagRobin Murphy2018-07-271-3/+3
| | | | | | | | | | | | | | | | | | | | Whilst the notion of an upstream DMA restriction is most commonly seen in PCI host bridges saddled with a 32-bit native interface, a more general version of the same issue can exist on complex SoCs where a bus or point-to-point interconnect link from a device's DMA master interface to another component along the path to memory (often an IOMMU) may carry fewer address bits than the interfaces at both ends nominally support. In order to properly deal with this, the first step is to expand the dma_32bit_limit flag into an arbitrary mask. To minimise the impact on existing code, we'll make sure to only consider this new mask valid if set. That makes sense anyway, since a mask of zero would represent DMA not being wired up at all, and that would be better handled by not providing valid ops in the first place. Signed-off-by: Robin Murphy <robin.murphy@arm.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Christoph Hellwig <hch@lst.de>
* dma-mapping: move all DMA mapping code to kernel/dmaChristoph Hellwig2018-06-141-0/+204
Currently the code is split over various files with dma- prefixes in the lib/ and drives/base directories, and the number of files keeps growing. Move them into a single directory to keep the code together and remove the file name prefixes. To match the irq infrastructure this directory is placed under the kernel/ directory. Signed-off-by: Christoph Hellwig <hch@lst.de>
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