[PATCH v2 00/12] iommufd support pasid attach/replace

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]


PASID (Process Address Space ID) is a PCIe extension to tag the DMA
transactions out of a physical device, and most modern IOMMU hardwares
have supported PASID granular address translation. So a PASID-capable
device can be attached to multiple hwpts (a.k.a. domains), each attachment
is tagged with a pasid.

This series first fixes the gap of existing set_dev_pasid() callback for
supporting domain replacement, then a missing iommu API to replace domain
for a pasid. Based on the iommu pasid attach/replace/detach APIs, this
series adds iommufd APIs for device drivers to attach/replace/detach pasid
to/from hwpt per userspace's request, and adds selftest to validate the
iommufd APIs.

pasid attach/replace is mandatory on Intel VT-d given the PASID table
locates in the physical address space hence must be managed by the kernel,
both for supporting vSVA and coming SIOV. But it's optional on ARM/AMD
which allow configuring the PASID/CD table either in host physical address
space or nested on top of an GPA address space. This series only add VT-d
support as the minimal requirement.

The completed code can be found in below link [1]. Heads up! The existing
iommufd selftest was broken, there was a fix [2] to it, but not upstreamed
yet. If wants to run iommufd selftest, please apply that fix. Sorry for the

[1] https://github.com/yiliu1765/iommufd/tree/iommufd_pasid
[2] https://lore.kernel.org/linux-iommu/20240111073213.180020-1-baolu.lu@xxxxxxxxxxxxxxx/

Change log:

 - Domain replace for pasid should be handled in set_dev_pasid() callbacks
   instead of remove_dev_pasid and call set_dev_pasid afteward in iommu
   layer (Jason)
 - Make xarray operations more self-contained in iommufd pasid attach/replace/detach
 - Tweak the dev_iommu_get_max_pasids() to allow iommu driver to populate the
   max_pasids. This makes the iommufd selftest simpler to meet the max_pasids
   check in iommu_attach_device_pasid()  (Jason)

v1: https://lore.kernel.org/kvm/20231127063428.127436-1-yi.l.liu@xxxxxxxxx/#r
 - Implemnet iommu_replace_device_pasid() to fall back to the original domain
   if this replacement failed (Kevin)
 - Add check in do_attach() to check corressponding attach_fn per the pasid value.

rfc: https://lore.kernel.org/linux-iommu/20230926092651.17041-1-yi.l.liu@xxxxxxxxx/

	Yi Liu

Lu Baolu (1):
  iommu/vt-d: Add set_dev_pasid callback for nested domain

Yi Liu (11):
  iommu: Pass old domain to set_dev_pasid op
  iommu: Introduce a replace API for device pasid
  iommufd: replace attach_fn with a structure
  iommufd: Support attach/replace hwpt per pasid
  iommu: Allow iommu driver to populate the max_pasids
  iommufd/selftest: Add set_dev_pasid and remove_dev_pasid in mock iommu
  iommufd/selftest: Add a helper to get test device
  iommufd/selftest: Add test ops to test pasid attach/detach
  iommufd/selftest: Add coverage for iommufd pasid attach/detach
  iommu/vt-d: Return if no dev_pasid is found in domain
  iommu/vt-d: Make intel_iommu_set_dev_pasid() to handle domain

 drivers/iommu/intel/iommu.c                   |  29 ++-
 drivers/iommu/intel/iommu.h                   |   3 +
 drivers/iommu/intel/nested.c                  |  15 ++
 drivers/iommu/intel/svm.c                     |   3 +-
 drivers/iommu/iommu-priv.h                    |   3 +
 drivers/iommu/iommu.c                         | 102 ++++++++-
 drivers/iommu/iommufd/Makefile                |   1 +
 drivers/iommu/iommufd/device.c                |  43 ++--
 drivers/iommu/iommufd/iommufd_private.h       |  23 ++
 drivers/iommu/iommufd/iommufd_test.h          |  30 +++
 drivers/iommu/iommufd/pasid.c                 | 161 ++++++++++++++
 drivers/iommu/iommufd/selftest.c              | 198 ++++++++++++++++-
 include/linux/iommu.h                         |   2 +-
 include/linux/iommufd.h                       |   6 +
 tools/testing/selftests/iommu/iommufd.c       | 207 ++++++++++++++++++
 .../selftests/iommu/iommufd_fail_nth.c        |  28 ++-
 tools/testing/selftests/iommu/iommufd_utils.h |  78 +++++++
 17 files changed, 888 insertions(+), 44 deletions(-)
 create mode 100644 drivers/iommu/iommufd/pasid.c


[Index of Archives]     [KVM ARM]     [KVM ia64]     [KVM ppc]     [Virtualization Tools]     [Spice Development]     [Libvirt]     [Libvirt Users]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite Questions]     [Linux Kernel]     [Linux SCSI]     [XFree86]

  Powered by Linux