aboutsummaryrefslogtreecommitdiffstats
path: root/kernel/dma/direct.c (follow)
AgeCommit message (Collapse)AuthorFilesLines
2018-08-17kernel/dma: remove unsupported gfp_mask parameter from dma_alloc_from_contiguous()Marek Szyprowski1-1/+2
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: MichaƂ 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>
2018-07-27dma-mapping: Generalise dma_32bit_limit flagRobin Murphy1-3/+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>
2018-06-14dma-mapping: move all DMA mapping code to kernel/dmaChristoph Hellwig1-0/+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>