Re: [PATCH ats_vtd v5 00/22] ATS support for VT-d

[Yi Liu <yi.l.liu@intel.com>]

On 2024/7/2 13:52, CLEMENT MATHIEU--DRIF wrote:
> From: Clement Mathieu--Drif <cmdetu@gmail.com>
> 
> This series belongs to a list of series that add SVM support for VT-d.
> 
> As a starting point, we use the series called 'intel_iommu: Enable stage-1 translation' (rfc2) by Zhenzhong Duan and Yi Liu.
> 
> Here we focus on the implementation of ATS support in the IOMMU and on a PCI-level
> API for ATS to be used by virtual devices.
> 
> This work is based on the VT-d specification version 4.1 (March 2023).
> Here is a link to a GitHub repository where you can find the following elements :
>      - Qemu with all the patches for SVM
>          - ATS
>          - PRI
>          - Device IOTLB invalidations
>          - Requests with already translated addresses
>      - A demo device
>      - A simple driver for the demo device
>      - A userspace program (for testing and demonstration purposes)
> 
> https://github.com/BullSequana/Qemu-in-guest-SVM-demo
> 
> v2
>      - handle huge pages better by detecting the page table level at which the translation errors occur
>      - Changes after review by ZhenZhong Duan :
>      	- Set the access bit after checking permissions
>      	- helper for PASID and ATS : make the commit message more accurate ('present' replaced with 'enabled')
>      	- pcie_pasid_init: add PCI_PASID_CAP_WIDTH_SHIFT and use it instead of PCI_EXT_CAP_PASID_SIZEOF for shifting the pasid width when preparing the capability register
>      	- pci: do not check pci_bus_bypass_iommu after calling pci_device_get_iommu_bus_devfn
>      	- do not alter formatting of IOMMUTLBEntry declaration
>      	- vtd_iova_fl_check_canonical : directly use s->aw_bits instead of aw for the sake of clarity
> 
> v3
>      - rebase on new version of Zhenzhong's flts implementation
>      - fix the atc lookup operation (check the mask before returning an entry)
>      - add a unit test for the ATC
>      - store a user pointer in the iommu notifiers to simplify the implementation of svm devices
>      Changes after review by Zhenzhong :
>      	- store the input pasid instead of rid2pasid when returning an entry after a translation
>      	- split the ATC implementation and its unit tests
> 
> v4
>      Changes after internal review
>      	- Fix the nowrite optimization, an ATS translation without the nowrite flag should not fail when the write permission is not set
> 
> v5
>      Changes after review by Philippe :
>      	- change the type of 'level' to unsigned in vtd_lookup_iotlb

Hi CMD,

I saw two v5 in my inbox, are they the same? :)

> Clément Mathieu--Drif (22):
>    intel_iommu: fix FRCD construction macro.
>    intel_iommu: make types match
>    intel_iommu: return page walk level even when the translation fails
>    intel_iommu: do not consider wait_desc as an invalid descriptor
>    memory: add permissions in IOMMUAccessFlags
>    pcie: add helper to declare PASID capability for a pcie device
>    pcie: helper functions to check if PASID and ATS are enabled
>    intel_iommu: declare supported PASID size
>    pci: cache the bus mastering status in the device
>    pci: add IOMMU operations to get address spaces and memory regions
>      with PASID
>    memory: store user data pointer in the IOMMU notifiers
>    pci: add a pci-level initialization function for iommu notifiers
>    intel_iommu: implement the get_address_space_pasid iommu operation
>    intel_iommu: implement the get_memory_region_pasid iommu operation
>    memory: Allow to store the PASID in IOMMUTLBEntry
>    intel_iommu: fill the PASID field when creating an instance of
>      IOMMUTLBEntry
>    atc: generic ATC that can be used by PCIe devices that support SVM
>    atc: add unit tests
>    memory: add an API for ATS support
>    pci: add a pci-level API for ATS
>    intel_iommu: set the address mask even when a translation fails
>    intel_iommu: add support for ATS
> 
>   hw/i386/intel_iommu.c                     | 146 +++++-
>   hw/i386/intel_iommu_internal.h            |   6 +-
>   hw/pci/pci.c                              | 127 +++++-
>   hw/pci/pcie.c                             |  42 ++
>   include/exec/memory.h                     |  51 ++-
>   include/hw/i386/intel_iommu.h             |   2 +-
>   include/hw/pci/pci.h                      | 101 +++++
>   include/hw/pci/pci_device.h               |   1 +
>   include/hw/pci/pcie.h                     |   9 +-
>   include/hw/pci/pcie_regs.h                |   3 +
>   include/standard-headers/linux/pci_regs.h |   1 +
>   system/memory.c                           |  20 +
>   tests/unit/meson.build                    |   1 +
>   tests/unit/test-atc.c                     | 527 ++++++++++++++++++++++
>   util/atc.c                                | 211 +++++++++
>   util/atc.h                                | 117 +++++
>   util/meson.build                          |   1 +
>   17 files changed, 1332 insertions(+), 34 deletions(-)
>   create mode 100644 tests/unit/test-atc.c
>   create mode 100644 util/atc.c
>   create mode 100644 util/atc.h
> 

-- 
Regards,
Yi Liu