[PATCH v12 0/9] iommu/amd: Use 128-bit cmpxchg operation to update DTE

Suravee Suthikulpanit posted 9 patches 3 days, 7 hours ago
drivers/iommu/amd/amd_iommu.h       |   4 +-
drivers/iommu/amd/amd_iommu_types.h |  41 ++-
drivers/iommu/amd/init.c            | 229 +++++++++--------
drivers/iommu/amd/iommu.c           | 378 +++++++++++++++++++++-------
4 files changed, 440 insertions(+), 212 deletions(-)
[PATCH v12 0/9] iommu/amd: Use 128-bit cmpxchg operation to update DTE
Posted by Suravee Suthikulpanit 3 days, 7 hours ago
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.

Also, this has been a long series. I would like to thank several folks who
have helped review and provide suggestions along the way :)

Changes in v12:
* Patch 4: Use arch_cmpxchg128_local() instead in amd_iommu_atomic128_set()
  and add Reviewed-by tag from Uros.
* Patch 5: Add Reviewed-by tag from Jason.

v11: https://lore.kernel.org/lkml/20241114194436.389961-1-suravee.suthikulpanit@amd.com/
v10: https://lore.kernel.org/lkml/20241113120327.5239-1-suravee.suthikulpanit@amd.com/
v9: https://lore.kernel.org/lkml/20241101162304.4688-1-suravee.suthikulpanit@amd.com/
v8: https://lore.kernel.org/lkml/20241031184243.4184-1-suravee.suthikulpanit@amd.com/
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()

 drivers/iommu/amd/amd_iommu.h       |   4 +-
 drivers/iommu/amd/amd_iommu_types.h |  41 ++-
 drivers/iommu/amd/init.c            | 229 +++++++++--------
 drivers/iommu/amd/iommu.c           | 378 +++++++++++++++++++++-------
 4 files changed, 440 insertions(+), 212 deletions(-)

-- 
2.34.1