Shared Virtual Addressing (SVA) allows to share process page tables with devices using the IOMMU, PASIDs and I/O page faults. Add SVA support to the Arm SMMUv3 driver. Since v5 [1]: * Added patches 1-3. Patch 1 adds a PASID field to mm_struct as discussed in [1] and [2]. This is also needed for Intel ENQCMD. Patch 2 adds refcounts to IOASID and patch 3 adds a couple of helpers to allocate the PASID. * Dropped most of iommu-sva.c. After getting rid of io_mm following review of v5, there wasn't enough generic code left to justify the indirect branch overhead of io_mm_ops in the MMU notifiers. I ended up with more glue than useful code, and couldn't find an easy way to deal with domains in the SMMU driver (we keep PASID tables per domain, while x86 keeps them per device). The direct approach in patch 17 is nicer and a little easier to read. The SMMU driver only gained 160 lines, while iommu-sva lost 470 lines. As a result I dropped the MMU notifier patch. Jacob, one upside of this rework is that we now free ioasids in blocking context, which might help with your addition of notifiers to ioasid.c * Simplified io-pgfault a bit, since flush() isn't called from mm exit path anymore. * Fixed a bug in patch 17 (don't clear the stall bit when stall is forced). You can find the latest version on https://jpbrucker.net/git/linux branch sva/current, and sva/zip-devel for the Hisilicon zip accelerator. [1] https://lore.kernel.org/linux-iommu/20200414170252.714402-1-jean-philippe@xxxxxxxxxx/ [2] https://lore.kernel.org/linux-iommu/1585596788-193989-6-git-send-email-fenghua.yu@xxxxxxxxx/ Jean-Philippe Brucker (25): mm: Add a PASID field to mm_struct iommu/ioasid: Add ioasid references iommu/sva: Add PASID helpers iommu: Add a page fault handler iommu/iopf: Handle mm faults arm64: mm: Add asid_gen_match() helper arm64: mm: Pin down ASIDs for sharing mm with devices iommu/io-pgtable-arm: Move some definitions to a header iommu/arm-smmu-v3: Manage ASIDs with xarray arm64: cpufeature: Export symbol read_sanitised_ftr_reg() iommu/arm-smmu-v3: Share process page tables iommu/arm-smmu-v3: Seize private ASID iommu/arm-smmu-v3: Add support for VHE iommu/arm-smmu-v3: Enable broadcast TLB maintenance iommu/arm-smmu-v3: Add SVA feature checking iommu/arm-smmu-v3: Add SVA device feature iommu/arm-smmu-v3: Implement iommu_sva_bind/unbind() iommu/arm-smmu-v3: Hook up ATC invalidation to mm ops iommu/arm-smmu-v3: Add support for Hardware Translation Table Update iommu/arm-smmu-v3: Maintain a SID->device structure dt-bindings: document stall property for IOMMU masters iommu/arm-smmu-v3: Add stall support for platform devices PCI/ATS: Add PRI stubs PCI/ATS: Export PRI functions iommu/arm-smmu-v3: Add support for PRI drivers/iommu/Kconfig | 11 + drivers/iommu/Makefile | 2 + .../devicetree/bindings/iommu/iommu.txt | 18 + arch/arm64/include/asm/mmu.h | 1 + arch/arm64/include/asm/mmu_context.h | 11 +- drivers/iommu/io-pgtable-arm.h | 30 + drivers/iommu/iommu-sva.h | 15 + include/linux/ioasid.h | 10 +- include/linux/iommu.h | 53 + include/linux/mm_types.h | 4 + include/linux/pci-ats.h | 8 + arch/arm64/kernel/cpufeature.c | 1 + arch/arm64/mm/context.c | 103 +- drivers/iommu/arm-smmu-v3.c | 1554 +++++++++++++++-- drivers/iommu/io-pgfault.c | 458 +++++ drivers/iommu/io-pgtable-arm.c | 27 +- drivers/iommu/ioasid.c | 30 +- drivers/iommu/iommu-sva.c | 85 + drivers/iommu/of_iommu.c | 5 +- drivers/pci/ats.c | 4 + MAINTAINERS | 3 +- 21 files changed, 2275 insertions(+), 158 deletions(-) create mode 100644 drivers/iommu/io-pgtable-arm.h create mode 100644 drivers/iommu/iommu-sva.h create mode 100644 drivers/iommu/io-pgfault.c create mode 100644 drivers/iommu/iommu-sva.c -- 2.26.2
