Re: [PATCH 00/18] Shared virtual address IOMMU and VT-d support

Andriy Shevchenko
2019-04-09T09:56:23Z

On Mon, Apr 08, 2019 at 04:59:15PM -0700, Jacob Pan wrote:
> 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.

This seems missed the comments I gave you internally.

>
> .-------------. .---------------------------.
> | 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] [PATCH v6 00/22] SMMUv3 Nested Stage Setup by Eric Auger
> https://lkml.org/lkml/2019/3/17/124
>
> [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
>
> 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], which has a v7 just published with
> no real impact to the patches used here. 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.
>
>
> Jacob Pan (15):
> ioasid: Add custom IOASID allocator
> ioasid: Convert ioasid_idr to XArray
> driver core: add per device iommu param
> iommu: introduce device fault data
> iommu: introduce device fault report API
> iommu: Introduce attach/detach_pasid_table API
> iommu/vt-d: Add custom allocator for IOASID
> iommu/vt-d: Replace Intel specific PASID allocator with IOASID
> iommu: Add guest PASID bind function
> iommu/vt-d: Move domain helper to header
> iommu/vt-d: Add nested translation support
> iommu/vt-d: Add bind guest PASID support
> iommu: add max num of cache and granu types
> iommu/vt-d: Support flushing more translation cache types
> iommu/vt-d: Add svm/sva invalidate function
>
> Jean-Philippe Brucker (1):
> drivers core: Add I/O ASID allocator
>
> Liu, Yi L (1):
> iommu: Introduce cache_invalidate API
>
> Lu Baolu (1):
> iommu/vt-d: Enlightened PASID allocation
>
> drivers/base/Kconfig | 7 ++
> drivers/base/Makefile | 1 +
> drivers/base/ioasid.c | 211 +++++++++++++++++++++++++++++++++++++
> drivers/iommu/Kconfig | 1 +
> drivers/iommu/dmar.c | 48 +++++++++
> drivers/iommu/intel-iommu.c | 219 ++++++++++++++++++++++++++++++++++++--
> drivers/iommu/intel-pasid.c | 191 +++++++++++++++++++++++++++++-----
> drivers/iommu/intel-pasid.h | 24 ++++-
> drivers/iommu/intel-svm.c | 217 +++++++++++++++++++++++++++++++++++---
> drivers/iommu/iommu.c | 207 +++++++++++++++++++++++++++++++++++-
> include/linux/device.h | 3 +
> include/linux/intel-iommu.h | 40 +++++--
> include/linux/intel-svm.h | 7 ++
> include/linux/ioasid.h | 66 ++++++++++++
> include/linux/iommu.h | 127 +++++++++++++++++++++++
> include/uapi/linux/iommu.h | 248 ++++++++++++++++++++++++++++++++++++++++++++
> 16 files changed, 1559 insertions(+), 58 deletions(-)
> create mode 100644 drivers/base/ioasid.c
> create mode 100644 include/linux/ioasid.h
> create mode 100644 include/uapi/linux/iommu.h
>
> --
> 2.7.4
>

--
With Best Regards,
Andy Shevchenko