[PATCH v2 00/11] iommu/arm-smmu-v3: Allocate vmid per vsmmu instead of s2_parent

[Nicolin Chen]

With a system having multiple SMMU physical instances, multiple vSMMUs can
be allocated for a VM that deivces behind different SMMUs are assigned to.
In such a use case, the IPA->PA mappings (i.e. the stage-2 I/O page table)
can be shared across the vSMMU instances.

With a shareable S2 parent domain, it is more natural to store a vmid per
vSMMU instance v.s. a shared S2 domain, since each physical SMMU instance
maintains its own vmid bitmap.

Have a few patches to get the functions ready for the vmid migration. And
decouple the vmid from S2 parent domains and move its allocation to vSMMU
instances. Note that a regular S2 domain (!nest_parent) has to retain the
s2_cfg and vmid for non-nesting use cases, if the SMMU HW doesn't support
stage 1. Maintain a per-S2-domain vsmmus list and a per-vSMMU ats_devices
list to iterate for S2 cache invalidation cmds and ATC invalidation cmds.

This is on Github:
https://github.com/nicolinc/iommufd/commits/smmuv3_vmid-v2

Changelog
v2
 * Add Reviewed-by from Jason and Pranjal
 * Add WARN_ON_ONCE(!vmid) in arm_smmu_make_s2_domain_ste()
 * Add arm_smmu_s2_parent_can_share() for a compatibility check
 * Introduce arm_smmu_s2_parent_tlb_inv_* helpers replacing the non-nesting
   routines
 * Introduce arm_vsmmu_atc_inv_domain() using a per-vSMMU ats_devices list,
   replacing the nested_ats_flush in struct arm_smmu_master_domain
v1
 https://lore.kernel.org/all/cover.1741150594.git.nicolinc@nvidia.com/

Thanks
Nicolin

Nicolin Chen (11):
  iommu/arm-smmu-v3: Pass in vmid to arm_smmu_make_s2_domain_ste()
  iommu/arm-smmu-v3: Pass in smmu/iommu_domain to
    __arm_smmu_tlb_inv_range()
  iommu/arm-smmu-v3: Share cmdq/cmd helpers with arm-smmu-v3-iommufd
  iommu/arm-smmu-v3: Add an inline arm_smmu_tlb_inv_vmid helper
  iommu/arm-smmu-v3: Rename arm_smmu_attach_prepare_vmaster
  iommu/arm-smmu-v3: Introduce arm_smmu_s2_parent_tlb_ invalidation
    helpers
  iommu/arm-smmu-v3: Introduce arm_vsmmu_atc_inv_domain()
  iommu/arm-smmu-v3: Use vSMMU helpers for S2 and ATC invalidations
  iommu/arm-smmu-v3: Clean up nested_ats_flush from master_domain
  iommu/arm-smmu-v3: Decouple vmid from S2 nest_parent domain
  iommu/arm-smmu-v3: Allow to share S2 nest_parent domain across vSMMUs

 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h   |  77 +++++++-
 .../arm/arm-smmu-v3/arm-smmu-v3-iommufd.c     | 175 ++++++++++++++++--
 .../iommu/arm/arm-smmu-v3/arm-smmu-v3-test.c  |   3 +-
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c   | 139 +++++++-------
 4 files changed, 297 insertions(+), 97 deletions(-)

-- 
2.43.0