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path: root/include/linux/dma-mapping.h
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2019-03-10Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds
Pull virtio updates from Michael Tsirkin: "Several fixes, most notably fix for virtio on swiotlb systems" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: vhost: silence an unused-variable warning virtio: hint if callbacks surprisingly might sleep virtio-ccw: wire up ->bus_name callback s390/virtio: handle find on invalid queue gracefully virtio-ccw: diag 500 may return a negative cookie virtio_balloon: remove the unnecessary 0-initialization virtio-balloon: improve update_balloon_size_func virtio-blk: Consider virtio_max_dma_size() for maximum segment size virtio: Introduce virtio_max_dma_size() dma: Introduce dma_max_mapping_size() swiotlb: Add is_swiotlb_active() function swiotlb: Introduce swiotlb_max_mapping_size()
2019-03-06dma: Introduce dma_max_mapping_size()Joerg Roedel
The function returns the maximum size that can be mapped using DMA-API functions. The patch also adds the implementation for direct DMA and a new dma_map_ops pointer so that other implementations can expose their limit. Cc: stable@vger.kernel.org Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-02-20dma-mapping: remove the DMA_MEMORY_EXCLUSIVE flagChristoph Hellwig
All users of dma_declare_coherent want their allocations to be exclusive, so default to exclusive allocations. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-20dma-mapping: remove dma_mark_declared_memory_occupiedChristoph Hellwig
This API is not used anywhere, so remove it. Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-02-20dma-mapping: improve selection of dma_declare_coherent availabilityChristoph Hellwig
This API is primarily used through DT entries, but two architectures and two drivers call it directly. So instead of selecting the config symbol for random architectures pull it in implicitly for the actual users. Also rename the Kconfig option to describe the feature better. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Paul Burton <paul.burton@mips.com> # MIPS Acked-by: Lee Jones <lee.jones@linaro.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-13dma-mapping: add a kconfig symbol for arch_teardown_dma_ops availabilityChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> # arm64
2019-02-13dma-mapping: add a kconfig symbol for arch_setup_dma_ops availabilityChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Paul Burton <paul.burton@mips.com> # MIPS Acked-by: Catalin Marinas <catalin.marinas@arm.com> # arm64
2019-02-01dma-mapping: don't BUG when calling dma_map_resource on RAMChristoph Hellwig
Use WARN_ON_ONCE to print a stack trace and return a proper error code instead. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Robin Murphy <robin.murphy@arm.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
2019-02-01dma-mapping: remove the default map_resource implementationChristoph Hellwig
Instead provide a proper implementation in the direct mapping code, and also wire it up for arm and powerpc, leaving an error return for all the IOMMU or virtual mapping instances for which we'd have to wire up an actual implementation Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
2019-01-08dma-mapping: remove dma_zalloc_coherent()Luis Chamberlain
dma_zalloc_coherent() is no longer needed as it has no users because dma_alloc_coherent() already zeroes out memory for us. The Coccinelle grammar rule that used to check for dma_alloc_coherent() + memset() is modified so that it just tells the user that the memset is not needed anymore. Suggested-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-01-04dma-mapping: properly stub out the DMA API for !CONFIG_HAS_DMAChristoph Hellwig
This avoids link failures in drivers using the DMA API, when they are compiled for user mode Linux with CONFIG_COMPILE_TEST=y. Fixes: 356da6d0cd ("dma-mapping: bypass indirect calls for dma-direct") Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-01-04dma-mapping: remove dmam_{declare,release}_coherent_memoryChristoph Hellwig
These functions have never been used. Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-01-04dma-mapping: implement dmam_alloc_coherent using dmam_alloc_attrsChristoph Hellwig
dmam_alloc_coherent is just the default no-flags case of dmam_alloc_attrs, so take advantage of this similar to the non-managed version. Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-01-04dma-mapping: implement dma_map_single_attrs using dma_map_page_attrsChristoph Hellwig
And also switch the way we implement the unmap side around to stay consistent. This ensures dma-debug works again because it records which function we used for mapping to ensure it is also used for unmapping, and also reduces further code duplication. Last but not least this also officially allows calling dma_sync_single_* for mappings created using dma_map_page, which is perfectly fine given that the sync calls only take a dma_addr_t, but not a virtual address or struct page. Fixes: 7f0fee242e ("dma-mapping: merge dma_unmap_page_attrs and dma_unmap_single_attrs") Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: LABBE Corentin <clabbe.montjoie@gmail.com>
2018-12-28Merge tag 'dma-mapping-4.21' of git://git.infradead.org/users/hch/dma-mappingLinus Torvalds
Pull DMA mapping updates from Christoph Hellwig: "A huge update this time, but a lot of that is just consolidating or removing code: - provide a common DMA_MAPPING_ERROR definition and avoid indirect calls for dma_map_* error checking - use direct calls for the DMA direct mapping case, avoiding huge retpoline overhead for high performance workloads - merge the swiotlb dma_map_ops into dma-direct - provide a generic remapping DMA consistent allocator for architectures that have devices that perform DMA that is not cache coherent. Based on the existing arm64 implementation and also used for csky now. - improve the dma-debug infrastructure, including dynamic allocation of entries (Robin Murphy) - default to providing chaining scatterlist everywhere, with opt-outs for the few architectures (alpha, parisc, most arm32 variants) that can't cope with it - misc sparc32 dma-related cleanups - remove the dma_mark_clean arch hook used by swiotlb on ia64 and replace it with the generic noncoherent infrastructure - fix the return type of dma_set_max_seg_size (Niklas Söderlund) - move the dummy dma ops for not DMA capable devices from arm64 to common code (Robin Murphy) - ensure dma_alloc_coherent returns zeroed memory to avoid kernel data leaks through userspace. We already did this for most common architectures, but this ensures we do it everywhere. dma_zalloc_coherent has been deprecated and can hopefully be removed after -rc1 with a coccinelle script" * tag 'dma-mapping-4.21' of git://git.infradead.org/users/hch/dma-mapping: (73 commits) dma-mapping: fix inverted logic in dma_supported dma-mapping: deprecate dma_zalloc_coherent dma-mapping: zero memory returned from dma_alloc_* sparc/iommu: fix ->map_sg return value sparc/io-unit: fix ->map_sg return value arm64: default to the direct mapping in get_arch_dma_ops PCI: Remove unused attr variable in pci_dma_configure ia64: only select ARCH_HAS_DMA_COHERENT_TO_PFN if swiotlb is enabled dma-mapping: bypass indirect calls for dma-direct vmd: use the proper dma_* APIs instead of direct methods calls dma-direct: merge swiotlb_dma_ops into the dma_direct code dma-direct: use dma_direct_map_page to implement dma_direct_map_sg dma-direct: improve addressability error reporting swiotlb: remove dma_mark_clean swiotlb: remove SWIOTLB_MAP_ERROR ACPI / scan: Refactor _CCA enforcement dma-mapping: factor out dummy DMA ops dma-mapping: always build the direct mapping code dma-mapping: move dma_cache_sync out of line dma-mapping: move various slow path functions out of line ...
2018-12-22dma-mapping: fix flags in dma_alloc_wcChristoph Hellwig
We really need the writecombine flag in dma_alloc_wc, fix a stupid oversight. Fixes: 7ed1d91a9e ("dma-mapping: translate __GFP_NOFAIL to DMA_ATTR_NO_WARN") Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-20dma-mapping: deprecate dma_zalloc_coherentChristoph Hellwig
We now always return zeroed memory from dma_alloc_coherent. Note that simply passing GFP_ZERO to dma_alloc_coherent wasn't always doing the right thing to start with given that various allocators are not backed by the page allocator and thus would ignore GFP_ZERO. Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-12-13dma-mapping: bypass indirect calls for dma-directChristoph Hellwig
Avoid expensive indirect calls in the fast path DMA mapping operations by directly calling the dma_direct_* ops if we are using the directly mapped DMA operations. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Tested-by: Jesper Dangaard Brouer <brouer@redhat.com> Tested-by: Tony Luck <tony.luck@intel.com>
2018-12-13dma-mapping: factor out dummy DMA opsRobin Murphy
The dummy DMA ops are currently used by arm64 for any device which has an invalid ACPI description and is thus barred from using DMA due to not knowing whether is is cache-coherent or not. Factor these out into general dma-mapping code so that they can be referenced from other common code paths. In the process, we can prune all the optional callbacks which just do the same thing as the default behaviour, and fill in .map_resource for completeness. Signed-off-by: Robin Murphy <robin.murphy@arm.com> [hch: moved to a separate source file] Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Tested-by: Jesper Dangaard Brouer <brouer@redhat.com> Tested-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-12-13dma-mapping: move dma_cache_sync out of lineChristoph Hellwig
This isn't exactly a slow path routine, but it is not super critical either, and moving it out of line will help to keep the include chain clean for the following DMA indirection bypass work. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Tested-by: Jesper Dangaard Brouer <brouer@redhat.com> Tested-by: Tony Luck <tony.luck@intel.com>
2018-12-13dma-mapping: move various slow path functions out of lineChristoph Hellwig
There is no need to have all setup and coherent allocation / freeing routines inline. Move them out of line to keep the implemeation nicely encapsulated and save some kernel text size. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Tested-by: Jesper Dangaard Brouer <brouer@redhat.com> Tested-by: Tony Luck <tony.luck@intel.com>
2018-12-13dma-mapping: merge dma_unmap_page_attrs and dma_unmap_single_attrsChristoph Hellwig
The two functions are exactly the same, so don't bother implementing them twice. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Tested-by: Jesper Dangaard Brouer <brouer@redhat.com> Tested-by: Tony Luck <tony.luck@intel.com>
2018-12-13dma-mapping: simplify the dma_sync_single_range_for_{cpu,device} implementationChristoph Hellwig
We can just call the regular calls after adding offset the the address instead of reimplementing them. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Tested-by: Jesper Dangaard Brouer <brouer@redhat.com> Tested-by: Tony Luck <tony.luck@intel.com>
2018-12-06dma-mapping: return an error code from dma_mapping_errorChristoph Hellwig
Currently dma_mapping_error returns a boolean as int, with 1 meaning error. This is rather unusual and many callers have to convert it to errno value. The callers are highly inconsistent with error codes ranging from -ENOMEM over -EIO, -EINVAL and -EFAULT ranging to -EAGAIN. Return -ENOMEM which seems to be what the largest number of callers convert it to, and which also matches the typical error case where we are out of resources. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Russell King <rmk+kernel@armlinux.org.uk> Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-06dma-mapping: remove the mapping_error dma_map_ops methodChristoph Hellwig
No users left except for vmd which just forwards it. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-06dma-mapping: provide a generic DMA_MAPPING_ERRORChristoph Hellwig
Error handling of the dma_map_single and dma_map_page APIs is a little problematic at the moment, in that we use different encodings in the returned dma_addr_t to indicate an error. That means we require an additional indirect call to figure out if a dma mapping call returned an error, and a lot of boilerplate code to implement these semantics. Instead return the maximum addressable value as the error. As long as we don't allow mapping single-byte ranges with single-byte alignment this value can never be a valid return. Additionaly if drivers do not check the return value from the dma_map* routines this values means they will generally not be pointed to actual memory. Once the default value is added here we can start removing the various mapping_error methods and just rely on this generic check. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Robin Murphy <robin.murphy@arm.com> Acked-by: Russell King <rmk+kernel@armlinux.org.uk> Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-01dma-mapping: move the arm64 noncoherent alloc/free support to common codeChristoph Hellwig
The arm64 codebase to implement coherent dma allocation for architectures with non-coherent DMA is a good start for a generic implementation, given that is uses the generic remap helpers, provides the atomic pool for allocations that can't sleep and still is realtively simple and well tested. Move it to kernel/dma and allow architectures to opt into it using a config symbol. Architectures just need to provide a new arch_dma_prep_coherent helper to writeback an invalidate the caches for any memory that gets remapped for uncached access. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2018-11-27dma-mapping: fix return type of dma_set_max_seg_size()Niklas Söderlund
The function dma_set_max_seg_size() can return either 0 on success or -EIO on error. Change its return type from unsigned int to int to capture this. Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-10-09dma-mapping: translate __GFP_NOFAIL to DMA_ATTR_NO_WARNChristoph Hellwig
This allows all dma_map_ops instances to entirely rely on DMA_ATTR_NO_WARN going forward. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Robin Murphy <robin.murphy@arm.com>
2018-10-08dma-debug: Check for drivers mapping invalid addresses in dma_map_single()Stephen Boyd
I recently debugged a DMA mapping oops where a driver was trying to map a buffer returned from request_firmware() with dma_map_single(). Memory returned from request_firmware() is mapped into the vmalloc region and this isn't a valid region to map with dma_map_single() per the DMA documentation's "What memory is DMA'able?" section. Unfortunately, we don't really check that in the DMA debugging code, so enabling DMA debugging doesn't help catch this problem. Let's add a new DMA debug function to check for a vmalloc address or an invalid virtual address and print a warning if this happens. This makes it a little easier to debug these sorts of problems, instead of seeing odd behavior or crashes when drivers attempt to map the vmalloc space for DMA. Cc: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-10-01dma-mapping: make the get_required_mask method available unconditionallyChristoph Hellwig
This save some duplication for ia64, and makes the interface more general. In the long run we want each dma_map_ops instance to fill this out, but this will take a little more prep work. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2018-09-25Revert "dma-mapping: clear dev->dma_ops in arch_teardown_dma_ops"Christoph Hellwig
This reverts commit 46053c73685411915d3de50c5a0045beef32806b. This change breaks architectures setting up dma_ops in their own magic way and not using arch_setup_dma_ops, so revert it. Reported-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-09-20dma-mapping: support non-coherent devices in dma_common_get_sgtableChristoph Hellwig
We can use the arch_dma_coherent_to_pfn hook to provide a ->get_sgtable implementation. Note that this isn't an endorsement of this interface (which is a horrible bad idea), but it is required to move arm64 over to the generic code without a loss of functionality. Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-09-20dma-mapping: consolidate the dma mmap implementationsChristoph Hellwig
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
2018-09-20dma-mapping: merge direct and noncoherent opsChristoph Hellwig
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
2018-09-08dma-mapping: clear dev->dma_ops in arch_teardown_dma_opsChristoph Hellwig
There is no reason to leave the per-device dma_ops around when deconfiguring a device, so move this code from arm64 into the common code. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2018-09-08dma-mapping: remove dma_deconfigureChristoph Hellwig
This goes through a lot of hooks just to call arch_teardown_dma_ops. Replace it with a direct call instead. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2018-09-08dma-mapping: remove dma_configureChristoph Hellwig
There is no good reason for this indirection given that the method always exists. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2018-07-25dma-mapping: relax warning for per-device areasRobin Murphy
The reasons why dma_free_attrs() should not be called from IRQ context are not necessarily obvious and somewhat buried in the development history, so let's start by documenting the warning itself to help anyone who does happen to hit it and wonder what the deal is. However, this check turns out to be slightly over-restrictive for the way that per-device memory has been spliced into the general API, since for that case we know that dma_declare_coherent_memory() has created an appropriate CPU mapping for the entire area and nothing dynamic should be happening. Given that the usage model for per-device memory is often more akin to streaming DMA than 'real' coherent DMA (e.g. allocating and freeing space to copy short-lived packets in and out), it is also somewhat more reasonable for those operations to happen in IRQ handlers for such devices. Therefore, let's move the irqs_disabled() check down past the per-device area hook, so that that gets a chance to resolve the request before we reach definite "you're doing it wrong" territory. Reported-by: Fredrik Noring <noring@nocrew.org> Tested-by: Fredrik Noring <noring@nocrew.org> Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-28x86/pci-dma: switch the VIA 32-bit DMA quirk to use the struct device flagChristoph Hellwig
Instead of globally disabling > 32bit DMA using the arch_dma_supported hook walk the PCI bus under the actually affected bridge and mark every device with the dma_32bit_limit flag. This also gets rid of the arch_dma_supported hook entirely. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
2018-05-25dma-mapping: remove unused gfp_t parameter to arch_dma_alloc_attrsHuaisheng Ye
Signed-off-by: Huaisheng Ye <yehs1@lenovo.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-19dma-mapping: provide a generic dma-noncoherent implementationChristoph Hellwig
Add a new dma_map_ops implementation that uses dma-direct for the address mapping of streaming mappings, and which requires arch-specific implemenations of coherent allocate/free. Architectures have to provide flushing helpers to ownership trasnfers to the device and/or CPU, and can provide optional implementations of the coherent mmap functionality, and the cache_flush routines for non-coherent long term allocations. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Alexey Brodkin <abrodkin@synopsys.com> Acked-by: Vineet Gupta <vgupta@synopsys.com>
2018-05-09dma-mapping: move the NEED_DMA_MAP_STATE config symbol to lib/KconfigChristoph Hellwig
This way we have one central definition of it, and user can select it as needed. Note that we now also always select it when CONFIG_DMA_API_DEBUG is select, which fixes some incorrect checks in a few network drivers. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
2018-05-07PCI: remove PCI_DMA_BUS_IS_PHYSChristoph Hellwig
This was used by the ide, scsi and networking code in the past to determine if they should bounce payloads. Now that the dma mapping always have to support dma to all physical memory (thanks to swiotlb for non-iommu systems) there is no need to this crude hack any more. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Palmer Dabbelt <palmer@sifive.com> (for riscv) Reviewed-by: Jens Axboe <axboe@kernel.dk>
2018-04-05Merge tag 'dma-mapping-4.17' of git://git.infradead.org/users/hch/dma-mappingLinus Torvalds
Pull dma-mapping updates from Christoph Hellwig: "Very light this round as the interesting dma mapping changes went through the x86 tree. This just provides proper stubs for architectures not supporting dma (Geert Uytterhoeven)" * tag 'dma-mapping-4.17' of git://git.infradead.org/users/hch/dma-mapping: usb: gadget: Add NO_DMA dummies for DMA mapping API scsi: Add NO_DMA dummies for SCSI DMA mapping API mm: Add NO_DMA dummies for DMA pool API dma-coherent: Add NO_DMA dummies for managed DMA API dma-mapping: Convert NO_DMA get_dma_ops() into a real dummy
2018-03-28dma-mapping: Don't clear GFP_ZERO in dma_alloc_attrsChristoph Hellwig
Revert the clearing of __GFP_ZERO in dma_alloc_attrs and move it to dma_direct_alloc for now. While most common architectures always zero dma cohereny allocations (and x86 did so since day one) this is not documented and at least arc and s390 do not zero without the explicit __GFP_ZERO argument. Fixes: 57bf5a8963f8 ("dma-mapping: clear harmful GFP_* flags in common code") Reported-by: Evgeniy Didin <Evgeniy.Didin@synopsys.com> Reported-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Evgeniy Didin <Evgeniy.Didin@synopsys.com> Cc: iommu@lists.linux-foundation.org Link: https://lkml.kernel.org/r/20180328133535.17302-2-hch@lst.de
2018-03-16dma-coherent: Add NO_DMA dummies for managed DMA APIGeert Uytterhoeven
Add dummies for dmam_{alloc,free}_coherent(), to allow compile-testing if NO_DMA=y. This prevents the following from showing up later: ERROR: "dmam_alloc_coherent" [drivers/net/ethernet/arc/arc_emac.ko] undefined! ERROR: "dmam_free_coherent" [drivers/net/ethernet/apm/xgene/xgene-enet.ko] undefined! ERROR: "dmam_alloc_coherent" [drivers/net/ethernet/apm/xgene/xgene-enet.ko] undefined! ERROR: "dmam_alloc_coherent" [drivers/mtd/nand/hisi504_nand.ko] undefined! ERROR: "dmam_alloc_coherent" [drivers/mmc/host/dw_mmc.ko] undefined! Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Reviewed-by: Mark Brown <broonie@kernel.org> Acked-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-03-16dma-mapping: Convert NO_DMA get_dma_ops() into a real dummyGeert Uytterhoeven
If NO_DMA=y, get_dma_ops() returns a reference to the non-existing symbol bad_dma_ops, thus causing a link failure if it is ever used. Make get_dma_ops() return NULL instead, to avoid the link failure. This allows to improve compile-testing, and limits the need to keep on sprinkling dependencies on HAS_DMA all over the place. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Reviewed-by: Mark Brown <broonie@kernel.org> Acked-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-02-12dma-mapping: fix a comment typoChristoph Hellwig
Reported-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-01-15dma-direct: rename dma_noop to dma_directChristoph Hellwig
The trivial direct mapping implementation already does a virtual to physical translation which isn't strictly a noop, and will soon learn to do non-direct but linear physical to dma translations through the device offset and a few small tricks. Rename it to a better fitting name. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Vladimir Murzin <vladimir.murzin@arm.com>