[PATCH v7 00/10] iommu: SVA and IOPF refactoring

Lu Baolu
2022-05-19T07:24:26Z

Hi folks,

The former part of this series refactors the IOMMU SVA code by assigning
an SVA type of iommu_domain to a shared virtual address and replacing
sva_bind/unbind iommu ops with attach/detach_dev_pasid domain ops.

The latter part changes the existing I/O page fault handling framework
from only serving SVA to a generic one. Any driver or component could
handle the I/O page faults for its domain in its own way by installing
an I/O page fault handler.

This series has been functionally tested on an x86 machine and compile
tested for other architectures.

This series is also available on github:
[2] https://github.com/LuBaolu/intel-iommu/commits/iommu-sva-refactoring-v7

Please review and suggest.

Best regards,
baolu

Change log:
v7:
- Remove duplicate array for sva domain.
- Rename detach_dev_pasid to block_dev_pasid.
- Add raw device driver interfaces for iommufd.
- Other misc refinements and patch reorganization.
- Drop "dmaengine: idxd: Separate user and kernel pasid enabling" which
has been picked for dmaengine tree.

v6:
- https://lore.kernel.org/linux-iommu/20220510061738.2761430-1-baolu.lu@linux.intel.com/
- Refine the SVA basic data structures.
Link: https://lore.kernel.org/linux-iommu/YnFv0ps0Ad8v+7uH@myrica/
- Refine arm smmuv3 sva domain allocation.
- Fix a possible lock issue.
Link: https://lore.kernel.org/linux-iommu/YnFydE8j8l7Q4m+b@myrica/

v5:
- https://lore.kernel.org/linux-iommu/20220502014842.991097-1-baolu.lu@linux.intel.com/
- Address review comments from Jean-Philippe Brucker. Very appreciated!
- Remove redundant pci aliases check in
device_group_immutable_singleton().
- Treat all buses exept PCI as static in immutable singleton check.
- As the sva_bind/unbind() have already guaranteed sva domain free only
after iopf_queue_flush_dev(), remove the unnecessary domain refcount.
- Move domain get() out of the list iteration in iopf_handle_group().

v4:
- https://lore.kernel.org/linux-iommu/20220421052121.3464100-1-baolu.lu@linux.intel.com/
- Solve the overlap with another series and make this series
self-contained.
- No objection to the abstraction of data structure during v3 review.
Hence remove the RFC subject prefix.
- Refine the immutable singleton group code according to Kevin's
comments.

v3:
- https://lore.kernel.org/linux-iommu/20220410102443.294128-1-baolu.lu@linux.intel.com/
- Rework iommu_group_singleton_lockdown() by adding a flag to the group
that positively indicates the group can never have more than one
member, even after hot plug.
- Abstract the data structs used for iommu sva in a separated patches to
make it easier for review.
- I still keep the RFC prefix in this series as above two significant
changes need at least another round review to be finalized.
- Several misc refinements.

v2:
- https://lore.kernel.org/linux-iommu/20220329053800.3049561-1-baolu.lu@linux.intel.com/
- Add sva domain life cycle management to avoid race between unbind and
page fault handling.
- Use a single domain for each mm.
- Return a single sva handler for the same binding.
- Add a new helper to meet singleton group requirement.
- Rework the SVA domain allocation for arm smmu v3 driver and move the
pasid_bit initialization to device probe.
- Drop the patch "iommu: Handle IO page faults directly".
- Add mmget_not_zero(mm) in SVA page fault handler.

v1:
- https://lore.kernel.org/linux-iommu/20220320064030.2936936-1-baolu.lu@linux.intel.com/
- Initial post.

Lu Baolu (10):
iommu: Add pasids field in struct iommu_device
iommu: Remove SVM_FLAG_SUPERVISOR_MODE support
iommu/sva: Add iommu_sva_domain support
iommu/vt-d: Add SVA domain support
arm-smmu-v3/sva: Add SVA domain support
iommu/sva: Refactoring iommu_sva_bind/unbind_device()
iommu: Remove SVA related callbacks from iommu ops
iommu: Prepare IOMMU domain for IOPF
iommu: Per-domain I/O page fault handling
iommu: Rename iommu-sva-lib.{c,h}

include/linux/intel-iommu.h | 8 +-
include/linux/intel-svm.h | 13 -
include/linux/iommu.h | 113 +++++--
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 21 +-
.../iommu/{iommu-sva-lib.h => iommu-sva.h} | 16 +
drivers/dma/idxd/cdev.c | 2 +-
drivers/dma/idxd/init.c | 24 +-
.../iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c | 89 +++---
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 12 +-
drivers/iommu/intel/dmar.c | 4 +
drivers/iommu/intel/iommu.c | 9 +-
drivers/iommu/intel/svm.c | 135 +++-----
drivers/iommu/io-pgfault.c | 73 +----
drivers/iommu/iommu-sva-lib.c | 71 -----
drivers/iommu/iommu-sva.c | 297 ++++++++++++++++++
drivers/iommu/iommu.c | 191 +++++------
drivers/misc/uacce/uacce.c | 2 +-
drivers/iommu/Makefile | 2 +-
18 files changed, 629 insertions(+), 453 deletions(-)
rename drivers/iommu/{iommu-sva-lib.h => iommu-sva.h} (80%)
delete mode 100644 drivers/iommu/iommu-sva-lib.c
create mode 100644 drivers/iommu/iommu-sva.c

--
2.25.1