kernel/linux.git/include/linux/dma-mapping.h, branch linux-5.8.y

dma-pool: fix coherent pool allocations for IOMMU mappings

2020-09-03T09:29:34+00:00

[ Upstream commit 9420139f516d7fbc248ce17f35275cb005ed98ea ] When allocating coherent pool memory for an IOMMU mapping we don't care about the DMA mask. Move the guess for the initial GFP mask into the dma_direct_alloc_pages and pass dma_coherent_ok as a function pointer argument so that it doesn't get applied to the IOMMU case. Signed-off-by: Christoph Hellwig Tested-by: Amit Pundir Signed-off-by: Sasha Levin

dma-mapping: Add a new dma_need_sync API

2020-06-30T13:44:03+00:00

Add a new API to check if calls to dma_sync_single_for_{device,cpu} are required for a given DMA streaming mapping. Signed-off-by: Christoph Hellwig Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20200629130359.2690853-2-hch@lst.de

Merge tag 'dma-mapping-5.8-2' of git://git.infradead.org/users/hch/dma-mapping

2020-06-06T18:55:53+00:00

Pull dma-mapping helpers from Christoph Hellwig: "These were in a separate stable branch so that various media and drm trees could pull the in for bug fixes, but looking at linux-next that hasn't actually happened yet. Still sending the APIs to you in the hope that these bug fixes get picked up for 5.8 in one way or another. Summary: - add DMA mapping helpers for struct sg_table (Marek Szyprowski)" * tag 'dma-mapping-5.8-2' of git://git.infradead.org/users/hch/dma-mapping: iommu: add generic helper for mapping sgtable objects scatterlist: add generic wrappers for iterating over sgtable objects dma-mapping: add generic helpers for mapping sgtable objects

dma-mapping: add generic helpers for mapping sgtable objects

2020-05-13T13:43:29+00:00

struct sg_table is a common structure used for describing a memory buffer. It consists of a scatterlist with memory pages and DMA addresses (sgl entry), as well as the number of scatterlist entries: CPU pages (orig_nents entry) and DMA mapped pages (nents entry). It turned out that it was a common mistake to misuse nents and orig_nents entries, calling DMA-mapping functions with a wrong number of entries or ignoring the number of mapped entries returned by the dma_map_sg function. To avoid such issues, let's introduce a common wrappers operating directly on the struct sg_table objects, which take care of the proper use of the nents and orig_nents entries. Signed-off-by: Marek Szyprowski Reviewed-by: Robin Murphy Signed-off-by: Christoph Hellwig

dma-pool: add additional coherent pools to map to gfp mask

2020-04-20T10:09:40+00:00

The single atomic pool is allocated from the lowest zone possible since it is guaranteed to be applicable for any DMA allocation. Devices may allocate through the DMA API but not have a strict reliance on GFP_DMA memory. Since the atomic pool will be used for all non-blockable allocations, returning all memory from ZONE_DMA may unnecessarily deplete the zone. Provision for multiple atomic pools that will map to the optimal gfp mask of the device. When allocating non-blockable memory, determine the optimal gfp mask of the device and use the appropriate atomic pool. The coherent DMA mask will remain the same between allocation and free and, thus, memory will be freed to the same atomic pool it was allocated from. __dma_atomic_pool_init() will be changed to return struct gen_pool * later once dynamic expansion is added. Signed-off-by: David Rientjes Signed-off-by: Christoph Hellwig

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux; tag 'dma-mapping-5.5' of git://git.infradead.org/users/hch/dma-mapping

2019-11-28T19:16:43+00:00

Pull dma-mapping updates from Christoph Hellwig: - improve dma-debug scalability (Eric Dumazet) - tiny dma-debug cleanup (Dan Carpenter) - check for vmap memory in dma_map_single (Kees Cook) - check for dma_addr_t overflows in dma-direct when using DMA offsets (Nicolas Saenz Julienne) - switch the x86 sta2x11 SOC to use more generic DMA code (Nicolas Saenz Julienne) - fix arm-nommu dma-ranges handling (Vladimir Murzin) - use __initdata in CMA (Shyam Saini) - replace the bus dma mask with a limit (Nicolas Saenz Julienne) - merge the remapping helpers into the main dma-direct flow (me) - switch xtensa to the generic dma remap handling (me) - various cleanups around dma_capable (me) - remove unused dev arguments to various dma-noncoherent helpers (me) * 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux: * tag 'dma-mapping-5.5' of git://git.infradead.org/users/hch/dma-mapping: (22 commits) dma-mapping: treat dev->bus_dma_mask as a DMA limit dma-direct: exclude dma_direct_map_resource from the min_low_pfn check dma-direct: don't check swiotlb=force in dma_direct_map_resource dma-debug: clean up put_hash_bucket() powerpc: remove support for NULL dev in __phys_to_dma / __dma_to_phys dma-direct: avoid a forward declaration for phys_to_dma dma-direct: unify the dma_capable definitions dma-mapping: drop the dev argument to arch_sync_dma_for_* x86/PCI: sta2x11: use default DMA address translation dma-direct: check for overflows on 32 bit DMA addresses dma-debug: increase HASH_SIZE dma-debug: reorder struct dma_debug_entry fields xtensa: use the generic uncached segment support dma-mapping: merge the generic remapping helpers into dma-direct dma-direct: provide mmap and get_sgtable method overrides dma-direct: remove the dma_handle argument to __dma_direct_alloc_pages dma-direct: remove __dma_direct_free_pages usb: core: Remove redundant vmap checks kernel: dma-contiguous: mark CMA parameters __initdata/__initconst dma-debug: add a schedule point in debug_dma_dump_mappings() ...

dma-mapping: treat dev->bus_dma_mask as a DMA limit

2019-11-21T17:14:35+00:00

Using a mask to represent bus DMA constraints has a set of limitations. The biggest one being it can only hold a power of two (minus one). The DMA mapping code is already aware of this and treats dev->bus_dma_mask as a limit. This quirk is already used by some architectures although still rare. With the introduction of the Raspberry Pi 4 we've found a new contender for the use of bus DMA limits, as its PCIe bus can only address the lower 3GB of memory (of a total of 4GB). This is impossible to represent with a mask. To make things worse the device-tree code rounds non power of two bus DMA limits to the next power of two, which is unacceptable in this case. In the light of this, rename dev->bus_dma_mask to dev->bus_dma_limit all over the tree and treat it as such. Note that dev->bus_dma_limit should contain the higher accessible DMA address. Signed-off-by: Nicolas Saenz Julienne Reviewed-by: Robin Murphy Signed-off-by: Christoph Hellwig

dma-mapping: remove the DMA_ATTR_WRITE_BARRIER flag

2019-11-14T16:01:54+00:00

This flag is not implemented by any backend and only set by the ib_umem module in a single instance. Link: https://lore.kernel.org/r/20191113073214.9514-2-hch@lst.de Signed-off-by: Christoph Hellwig Reviewed-by: Jason Gunthorpe Signed-off-by: Jason Gunthorpe

dma-mapping: Add vmap checks to dma_map_single()

2019-10-30T18:09:25+00:00

As we've seen from USB and other areas[1], we need to always do runtime checks for DMA operating on memory regions that might be remapped. This adds vmap checks (similar to those already in USB but missing in other places) into dma_map_single() so all callers benefit from the checking. [1] https://git.kernel.org/linus/3840c5b78803b2b6cc1ff820100a74a092c40cbb Suggested-by: Laura Abbott Signed-off-by: Kees Cook [hch: fixed the printk message] Signed-off-by: Christoph Hellwig

dma-mapping: fix handling of dma-ranges for reserved memory (again)

2019-10-30T18:07:35+00:00

Daniele reported that issue previously fixed in c41f9ea998f3 ("drivers: dma-coherent: Account dma_pfn_offset when used with device tree") reappear shortly after 43fc509c3efb ("dma-coherent: introduce interface for default DMA pool") where fix was accidentally dropped. Lets put fix back in place and respect dma-ranges for reserved memory. Fixes: 43fc509c3efb ("dma-coherent: introduce interface for default DMA pool") Reported-by: Daniele Alessandrelli Tested-by: Daniele Alessandrelli Tested-by: Alexandre Torgue Signed-off-by: Vladimir Murzin Signed-off-by: Christoph Hellwig