kernel.git/arch/arm64/mm/dma-mapping.c, branch master

arm64: Properly clean up iommu-dma remnants

2024-05-10T07:04:25Z

Thanks to the somewhat asymmetrical nature, while removing iommu_setup_dma_ops() from the arch_setup_dma_ops() flow, I managed to forget that arm64's teardown path was also specific to iommu-dma. Clean that up to match, otherwise probe deferral will lead to the arch code erroneously removing DMA ops set elsewhere. Reported-by: Dmitry Baryshkov Link: https://lore.kernel.org/linux-iommu/Zi_LV28TR-P-PzXi@eriador.lumag.spb.ru/ Fixes: b67483b3c44e ("iommu/dma: Centralise iommu_setup_dma_ops()") Signed-off-by: Robin Murphy Tested-by: Dmitry Baryshkov Acked-by: Catalin Marinas Reviewed-by: Konrad Dybcio Acked-by: Will Deacon Tested-by: Nicolin Chen Link: https://lore.kernel.org/r/d4cc20cbb0c45175e98dd76bf187e2ad6421296d.1714472573.git.robin.murphy@arm.com Signed-off-by: Joerg Roedel

dma-mapping: Simplify arch_setup_dma_ops()

2024-04-26T10:07:28Z

The dma_base, size and iommu arguments are only used by ARM, and can now easily be deduced from the device itself, so there's no need to pass them through the callchain as well. Acked-by: Rob Herring Reviewed-by: Christoph Hellwig Reviewed-by: Michael Kelley # For Hyper-V Reviewed-by: Jason Gunthorpe Tested-by: Hanjun Guo Signed-off-by: Robin Murphy Acked-by: Catalin Marinas Link: https://lore.kernel.org/r/5291c2326eab405b1aa7693aa964e8d3cb7193de.1713523152.git.robin.murphy@arm.com Signed-off-by: Joerg Roedel

iommu/dma: Centralise iommu_setup_dma_ops()

2024-04-26T10:07:26Z

It's somewhat hard to see, but arm64's arch_setup_dma_ops() should only ever call iommu_setup_dma_ops() after a successful iommu_probe_device(), which means there should be no harm in achieving the same order of operations by running it off the back of iommu_probe_device() itself. This then puts it in line with the x86 and s390 .probe_finalize bodges, letting us pull it all into the main flow properly. As a bonus this lets us fold in and de-scope the PCI workaround setup as well. At this point we can also then pull the call up inside the group mutex, and avoid having to think about whether iommu_group_store_type() could theoretically race and free the domain if iommu_setup_dma_ops() ran just *before* iommu_device_use_default_domain() claims it... Furthermore we replace one .probe_finalize call completely, since the only remaining implementations are now one which only needs to run once for the initial boot-time probe, and two which themselves render that path unreachable. This leaves us a big step closer to realistically being able to unpick the variety of different things that iommu_setup_dma_ops() has been muddling together, and further streamline iommu-dma into core API flows in future. Reviewed-by: Lu Baolu # For Intel IOMMU Reviewed-by: Jason Gunthorpe Tested-by: Hanjun Guo Signed-off-by: Robin Murphy Acked-by: Catalin Marinas Link: https://lore.kernel.org/r/bebea331c1d688b34d9862eefd5ede47503961b8.1713523152.git.robin.murphy@arm.com Signed-off-by: Joerg Roedel

iommu: Remove struct iommu_ops *iommu from arch_setup_dma_ops()

2023-12-12T09:18:45Z

This is not being used to pass ops, it is just a way to tell if an iommu driver was probed. These days this can be detected directly via device_iommu_mapped(). Call device_iommu_mapped() in the two places that need to check it and remove the iommu parameter everywhere. Reviewed-by: Jerry Snitselaar Reviewed-by: Lu Baolu Reviewed-by: Moritz Fischer Acked-by: Christoph Hellwig Acked-by: Rob Herring Tested-by: Hector Martin Signed-off-by: Jason Gunthorpe Link: https://lore.kernel.org/r/1-v2-16e4def25ebb+820-iommu_fwspec_p1_jgg@nvidia.com Signed-off-by: Joerg Roedel

Revert "Revert "arm64: dma: Drop cache invalidation from arch_dma_prep_coherent()""

2023-03-30T15:23:03Z

This reverts commit b7d9aae404841d9999b7476170867ae441e948d2. With the Qualcomm remoteproc driver now modified to use a carveout memory region in 57f72170a2b2 ("remoteproc: qcom_q6v5_mss: Use a carveout to authenticate modem headers"), we can reinstate c44094eee32f ("arm64: dma: Drop cache invalidation from arch_dma_prep_coherent()") which relaxes the arm64 implementation of arch_dma_prep_coherent() to perform only a data cache clean operation, rather than a clean-and-invalidate. Signed-off-by: Will Deacon

Revert "arm64: dma: Drop cache invalidation from arch_dma_prep_coherent()"

2022-12-06T17:30:39Z

This reverts commit c44094eee32f32f175aadc0efcac449d99b1bbf7. Although the semantics of the DMA API require only a clean operation here, it turns out that the Qualcomm 'qcom_q6v5_mss' remoteproc driver (ab)uses the DMA API for transferring the modem firmware to the secure world via calls to Trustzone [1]. Once the firmware buffer has changed hands, _any_ access from the non-secure side (i.e. Linux) will be detected on the bus and result in a full system reset [2]. Although this is possible even with this revert in place (due to speculative reads via the cacheable linear alias of memory), anecdotally the problem occurs considerably more frequently when the lines have not been invalidated, assumedly due to some micro-architectural interactions with the cache hierarchy. Revert the offending change for now, along with a comment, so that the Qualcomm developers have time to fix the driver [3] to use a firmware buffer which does not have a cacheable alias in the linear map. Link: https://lore.kernel.org/r/20221114110329.68413-1-manivannan.sadhasivam@linaro.org [1] Link: https://lore.kernel.org/r/CAMi1Hd3H2k1J8hJ6e-Miy5+nVDNzv6qQ3nN-9929B0GbHJkXEg@mail.gmail.com/ [2] Link: https://lore.kernel.org/r/20221206092152.GD15486@thinkpad [2] Reported-by: Amit Pundir Reported-by: Manivannan Sadhasivam Cc: Thorsten Leemhuis Cc: Sibi Sankar Signed-off-by: Will Deacon Acked-by: Manivannan Sadhasivam Link: https://lore.kernel.org/r/20221206103403.646-1-will@kernel.org Signed-off-by: Catalin Marinas

Merge tag 'iommu-updates-v6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

2022-10-10T20:20:53Z

Pull iommu updates from Joerg Roedel: - remove the bus_set_iommu() interface which became unnecesary because of IOMMU per-device probing - make the dma-iommu.h header private - Intel VT-d changes from Lu Baolu: - Decouple PASID and PRI from SVA - Add ESRTPS & ESIRTPS capability check - Cleanups - Apple DART support for the M1 Pro/MAX SOCs - support for AMD IOMMUv2 page-tables for the DMA-API layer. The v2 page-tables are compatible with the x86 CPU page-tables. Using them for DMA-API prepares support for hardware-assisted IOMMU virtualization - support for MT6795 Helio X10 M4Us in the Mediatek IOMMU driver - some smaller fixes and cleanups * tag 'iommu-updates-v6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (59 commits) iommu/vt-d: Avoid unnecessary global DMA cache invalidation iommu/vt-d: Avoid unnecessary global IRTE cache invalidation iommu/vt-d: Rename cap_5lp_support to cap_fl5lp_support iommu/vt-d: Remove pasid_set_eafe() iommu/vt-d: Decouple PASID & PRI enabling from SVA iommu/vt-d: Remove unnecessary SVA data accesses in page fault path dt-bindings: iommu: arm,smmu-v3: Relax order of interrupt names iommu: dart: Support t6000 variant iommu/io-pgtable-dart: Add DART PTE support for t6000 iommu/io-pgtable: Add DART subpage protection support iommu/io-pgtable: Move Apple DART support to its own file iommu/mediatek: Add support for MT6795 Helio X10 M4Us iommu/mediatek: Introduce new flag TF_PORT_TO_ADDR_MT8173 dt-bindings: mediatek: Add bindings for MT6795 M4U iommu/iova: Fix module config properly iommu/amd: Fix sparse warning iommu/amd: Remove outdated comment iommu/amd: Free domain ID after domain_flush_pages iommu/amd: Free domain id in error path iommu/virtio: Fix compile error with viommu_capable() ...

arm64: dma: Drop cache invalidation from arch_dma_prep_coherent()

2022-09-22T14:09:31Z

arch_dma_prep_coherent() is called when preparing a non-cacheable region for a consistent DMA buffer allocation. Since the buffer pages may previously have been written via a cacheable mapping and consequently allocated as dirty cachelines, the purpose of this function is to remove these dirty lines from the cache, writing them back so that the non-coherent device is able to see them. On arm64, this operation can be achieved with a clean to the point of coherency; a subsequent invalidation is not required and serves little purpose in the presence of a cacheable alias (e.g. the linear map), since clean lines can be speculatively fetched back into the cache after the invalidation operation has completed. Relax the cache maintenance in arch_dma_prep_coherent() so that only a clean, and not a clean-and-invalidate operation is performed. Cc: Mark Rutland Cc: Robin Murphy Cc: Christoph Hellwig Cc: Ard Biesheuvel Signed-off-by: Will Deacon Reviewed-by: Catalin Marinas Link: https://lore.kernel.org/r/20220823122111.17439-1-will@kernel.org Signed-off-by: Catalin Marinas

iommu/dma: Move public interfaces to linux/iommu.h

2022-09-07T12:47:00Z

The iommu-dma layer is now mostly encapsulated by iommu_dma_ops, with only a couple more public interfaces left pertaining to MSI integration. Since these depend on the main IOMMU API header anyway, move their declarations there, taking the opportunity to update the half-baked comments to proper kerneldoc along the way. Signed-off-by: Robin Murphy Acked-by: Catalin Marinas Acked-by: Marc Zyngier Link: https://lore.kernel.org/r/9cd99738f52094e6bed44bfee03fa4f288d20695.1660668998.git.robin.murphy@arm.com Signed-off-by: Joerg Roedel

arm64: mm: Remove assembly DMA cache maintenance wrappers

2022-07-05T12:06:31Z

Remove the __dma_{flush,map,unmap}_area assembly wrappers and call the appropriate cache maintenance functions directly from the DMA mapping callbacks. Reviewed-by: Catalin Marinas Reviewed-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20220610151228.4562-3-will@kernel.org Signed-off-by: Will Deacon