Shared virtual address (SVA), a.k.a, Shared virtual memory (SVM) on Intel platforms allow address space sharing between device DMA and applications. SVA can reduce programming complexity and enhance security. This series is intended to enable SVA virtualization, i.e. shared guest application address space and physical device DMA address. Only IOMMU portion of the changes are included in this series. Additional support is needed in VFIO and QEMU (will be submitted separately) to complete this functionality.
To make incremental changes and reduce the size of each patchset. This series does not inlcude support for page request services. In VT-d implementation, PASID table is per device and maintained in the host. Guest PASID table is shadowed in VMM where virtual IOMMU is emulated. .-------------. .---------------------------. | vIOMMU | | Guest process CR3, FL only| | | '---------------------------' .----------------/ | PASID Entry |--- PASID cache flush - '-------------' | | | V | | CR3 in GPA '-------------' Guest ------| Shadow |--------------------------|-------- v v v Host .-------------. .----------------------. | pIOMMU | | Bind FL for GVA-GPA | | | '----------------------' .----------------/ | | PASID Entry | V (Nested xlate) '----------------\.------------------------------. | | |SL for GPA-HPA, default domain| | | '------------------------------' '-------------' Where: - FL = First level/stage one page tables - SL = Second level/stage two page tables This work is based on collaboration with other developers on the IOMMU mailing list. Notably, [1] Common APIs git://linux-arm.org/linux-jpb.git sva/api [2] [RFC PATCH 2/6] drivers core: Add I/O ASID allocator by Jean-Philippe Brucker https://www.spinics.net/lists/iommu/msg30639.html [3] [RFC PATCH 0/5] iommu: APIs for paravirtual PASID allocation by Lu Baolu https://lkml.org/lkml/2018/11/12/1921 [4] [PATCH v5 00/23] IOMMU and VT-d driver support for Shared Virtual Address (SVA) https://lwn.net/Articles/754331/ There are roughly three parts: 1. Generic PASID allocator [1] with extension to support custom allocator 2. IOMMU cache invalidation passdown from guest to host 3. Guest PASID bind for nested translation All generic IOMMU APIs are reused from [1] with minor tweaks. With this patchset, guest SVA without page request works on VT-d. PRS patches will come next as we try to avoid large patchset that is hard to review. The patches for basic SVA support (w/o PRS) starts: [PATCH v5 05/19] iommu: Introduce attach/detach_pasid_table API It is worth noting that unlike sMMU nested stage setup, where PASID table is owned by the guest, VT-d PASID table is owned by the host, individual PASIDs are bound instead of the PASID table. This series is based on the new VT-d 3.0 Specification (https://software.intel.com/sites/default/files/managed/c5/15/vt-directed-io-spec.pdf). This is different than the older series in [4] which was based on the older specification that does not have scalable mode. ChangeLog: - V5 Rebased on v5.3-rc4 which has some of the IOMMU fault APIs merged. Addressed v4 review comments from Eric Auger, Baolu Lu, and Jonathan Cameron. Specific changes are as follows: - Refined custom IOASID allocator to support multiple vIOMMU, hotplug cases. - Extracted vendor data from IOMMU guest PASID bind data, for VT-d will support all necessary guest PASID entry fields for PASID bind. - Support non-identity host-guest PASID mapping - Exception handling in various cases - V4 - Redesigned IOASID allocator such that it can support custom allocators with shared helper functions. Use separate XArray to store IOASIDs per allocator. Took advice from Eric Auger to have default allocator use the generic allocator structure. Combined into one patch in that the default allocator is just "another" allocator now. Can be built as a module in case of driver use without IOMMU. - Extended bind guest PASID data to support SMMU and non-identity guest to host PASID mapping https://lkml.org/lkml/2019/5/21/802 - Rebased on Jean's sva/api common tree, new patches starts with [PATCH v4 10/22] - V3 - Addressed thorough review comments from Eric Auger (Thank you!) - Moved IOASID allocator from driver core to IOMMU code per suggestion by Christoph Hellwig (https://lkml.org/lkml/2019/4/26/462) - Rebased on top of Jean's SVA API branch and Eric's v7[1] (git://linux-arm.org/linux-jpb.git sva/api) - All IOMMU APIs are unmodified (except the new bind guest PASID call in patch 9/16) - V2 - Rebased on Joerg's IOMMU x86/vt-d branch v5.1-rc4 - Integrated with Eric Auger's new v7 series for common APIs (https://github.com/eauger/linux/tree/v5.1-rc3-2stage-v7) - Addressed review comments from Andy Shevchenko and Alex Williamson on IOASID custom allocator. - Support multiple custom IOASID allocators (vIOMMUs) and dynamic registration. Jacob Pan (14): iommu: Add a timeout parameter for PRQ response iommu: handle page response timeout iommu: Introduce attach/detach_pasid_table API iommu/ioasid: Add custom allocators iommu: Introduce guest PASID bind function iommu/vt-d: Add custom allocator for IOASID iommu/vt-d: Replace Intel specific PASID allocator with IOASID iommu/vt-d: Move domain helper to header iommu/vt-d: Avoid duplicated code for PASID setup iommu/vt-d: Add nested translation helper function iommu/vt-d: Misc macro clean up for SVM iommu/vt-d: Add bind guest PASID support iommu/vt-d: Support flushing more translation cache types iommu/vt-d: Add svm/sva invalidate function Jean-Philippe Brucker (3): trace/iommu: Add sva trace events iommu: Use device fault trace event iommu: Add I/O ASID allocator Lu Baolu (1): iommu/vt-d: Enlightened PASID allocation Yi L Liu (1): iommu: Introduce cache_invalidate API Documentation/admin-guide/kernel-parameters.txt | 8 + drivers/iommu/Kconfig | 5 + drivers/iommu/Makefile | 1 + drivers/iommu/dmar.c | 46 +++ drivers/iommu/intel-iommu.c | 259 +++++++++++++- drivers/iommu/intel-pasid.c | 343 ++++++++++++++++--- drivers/iommu/intel-pasid.h | 25 +- drivers/iommu/intel-svm.c | 298 +++++++++++++--- drivers/iommu/ioasid.c | 433 ++++++++++++++++++++++++ drivers/iommu/iommu.c | 139 ++++++++ include/linux/intel-iommu.h | 39 ++- include/linux/intel-svm.h | 17 + include/linux/ioasid.h | 75 ++++ include/linux/iommu.h | 58 ++++ include/trace/events/iommu.h | 84 +++++ include/uapi/linux/iommu.h | 219 ++++++++++++ 16 files changed, 1925 insertions(+), 124 deletions(-) create mode 100644 drivers/iommu/ioasid.c create mode 100644 include/linux/ioasid.h -- 2.7.4 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu