[PATCH v3 0/8] Refactor the SMMU's CD table ownership

Michael Shavit mshavit at google.com
Tue Aug 1 11:35:17 PDT 2023


Hi all,

This series refactors stage 1 domains so that they describe a single CD
entry. These entries are now inserted into a CD table that is owned by
the arm_smmu_master instead of the domain.
This is conceptually cleaner and unblocks other features, such as
attaching domains with PASID (for unmanaged/dma domains).

This patch series was originally part of a larger patch series that
implemented the set_dev_pasid callback for non-SVA domains but is now
split into a distinct series.

This patch series is also available on gerrit with Jean's SMMU test
engine patches cherry-picked on top for testing:
https://linux-review.googlesource.com/c/linux/kernel/git/torvalds/linux/+/24742/3

Thanks,
Michael Shavit

Changes in v3:
- Add a helper to write a CD to all masters that a domain is attached
  to.
- Fixed an issue where an arm_smmu_write_ctx_desc error return wasn't
  correctly handled by its caller.
- Flip the cd_table.installed bit back off when table is detached
- re-order the commit later in the series since flipping the installed
  bit to off isn't obvious when the cd_table is still shared by multiple
  masters.
- Link to v2: https://lore.kernel.org/all/20230731104833.800114-1-mshavit@google.com/

Changes in v2:
- Allocate CD table when it's first needed instead of on probe.
- Minor changes
- Added commit to rename remaining usages of cdcfg to cd_table
- Link to v1: https://lore.kernel.org/all/20230727182647.4106140-1-mshavit@google.com/

Changes in v1:
- Replace s1_cfg with arm_smmu_ctx_desc_cfg representing the CD table
- Assume that the CD table is owned by the SMMU master for most
  operations. This is forward-compatible with the nested patch series as
  these operations wouldn't be called when the installed CD table comes
  from nested domains.
- Split off as a distinct patch series from https://lore.kernel.org/all/20230621063825.268890-1-mshavit@google.com/

Michael Shavit (8):
  iommu/arm-smmu-v3: Move ctx_desc out of s1_cfg
  iommu/arm-smmu-v3: Replace s1_cfg with cdtab_cfg
  iommu/arm-smmu-v3: Encapsulate ctx_desc_cfg init in alloc_cd_tables
  iommu/arm-smmu-v3: move stall_enabled to the cd table
  iommu/arm-smmu-v3: Refactor write_ctx_desc
  iommu/arm-smmu-v3: Move CD table to arm_smmu_master
  iommu/arm-smmu-v3: Skip cd sync if CD table isn't active
  iommu/arm-smmu-v3: Rename cdcfg to cd_table

 .../iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c   |  33 ++-
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c   | 217 ++++++++----------
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h   |  21 +-
 3 files changed, 139 insertions(+), 132 deletions(-)


base-commit: 57012c57536f8814dec92e74197ee96c3498d24e
-- 
2.41.0.585.gd2178a4bd4-goog




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