[PATCH v8 00/10] iommu/amd: Use 128-bit cmpxchg operation to update DTE

Suravee Suthikulpanit
2024-10-31T18:43:05Z

This series modifies current implementation to use 128-bit cmpxchg to
update DTE when needed as specified in the AMD I/O Virtualization
Techonology (IOMMU) Specification.

Please note that I have verified with the hardware designer, and they have
confirmed that the IOMMU hardware has always been implemented with 256-bit
read. The next revision of the IOMMU spec will be updated to correctly
describe this part. Therefore, I have updated the implementation to avoid
unnecessary flushing.

Changes in v8:
* Patch 4: Add struct ivhd_dte_flags.segid
* Patch 6: Update amd_iommu_get_ivhd_dte_flags()

v7: https://lore.kernel.org/lkml/20241031091624.4895-1-suravee.suthikulpanit@amd.com/
v6: https://lore.kernel.org/lkml/20241016051756.4317-1-suravee.suthikulpanit@amd.com/
v5: https://lore.kernel.org/lkml/20241007041353.4756-1-suravee.suthikulpanit@amd.com/
v4: https://lore.kernel.org/lkml/20240916171805.324292-1-suravee.suthikulpanit@amd.com/
v3: https://lore.kernel.org/lkml/20240906121308.5013-1-suravee.suthikulpanit@amd.com/
v2: https://lore.kernel.org/lkml/20240829180726.5022-1-suravee.suthikulpanit@amd.com/
v1: https://lore.kernel.org/lkml/20240819161839.4657-1-suravee.suthikulpanit@amd.com/

Thanks,
Suravee

Suravee Suthikulpanit (9):
iommu/amd: Misc ACPI IVRS debug info clean up
iommu/amd: Disable AMD IOMMU if CMPXCHG16B feature is not supported
iommu/amd: Introduce struct ivhd_dte_flags to store persistent DTE
flags
iommu/amd: Introduce helper function to update 256-bit DTE
iommu/amd: Modify set_dte_entry() to use 256-bit DTE helpers
iommu/amd: Introduce helper function get_dte256()
iommu/amd: Modify clear_dte_entry() to avoid in-place update
iommu/amd: Lock DTE before updating the entry with WRITE_ONCE()
iommu/amd: Remove amd_iommu_apply_erratum_63()

Uros Bizjak (1):
asm/rwonce: Introduce [READ|WRITE]_ONCE() support for __int128

drivers/iommu/amd/amd_iommu.h | 4 +-
drivers/iommu/amd/amd_iommu_types.h | 41 ++-
drivers/iommu/amd/init.c | 230 +++++++++--------
drivers/iommu/amd/iommu.c | 370 ++++++++++++++++++++--------
include/asm-generic/rwonce.h | 2 +-
include/linux/compiler_types.h | 8 +-
6 files changed, 441 insertions(+), 214 deletions(-)

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2.34.1