[PATCH v4 0/8] Refactor the SMMU's CD table ownership

From: Michael Shavit
Date: Wed Aug 02 2023 - 12:33:47 EST

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:

Michael Shavit

Changes in v4:
- Added comment about the cd_table's dependency on the iommu core's
group mutex.
- Narrowed the range of code for which the domain's init_mutex is held
on attach since it now only protects the arm_smmu_domain_finalise
- Link to v3: https://lore.kernel.org/all/20230801183845.4026101-1-mshavit@xxxxxxxxxx/

Changes in v3:
- Add a helper to write a CD to all masters that a domain is attached
- 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
- Link to v2: https://lore.kernel.org/all/20230731104833.800114-1-mshavit@xxxxxxxxxx/

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@xxxxxxxxxx/#r

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@xxxxxxxxxx/

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 | 234 ++++++++----------
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 22 +-
3 files changed, 147 insertions(+), 142 deletions(-)

base-commit: 57012c57536f8814dec92e74197ee96c3498d24e