On Tue, Feb 25, 2025 at 09:25:40AM -0800, Nicolin Chen wrote:

Use it to store all vSMMU-related data. The vsid (Virtual Stream ID) will
be the first use case. Since the vsid reader will be the eventq handler
that already holds a streams_mutex, reuse that to fenche the vmaster too.

Also add a pair of arm_smmu_attach_prepare/commit_vmaster helpers to set
or unset the master->vmaster point. Put these helpers inside the existing
arm_smmu_attach_prepare/commit().

For identity/blocked ops that don't call arm_smmu_attach_prepare/commit(),
add a simpler arm_smmu_master_clear_vmaster helper to unset the vmaster.

Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Pranjal Shrivastavat <praan@google.com>
Signed-off-by: Nicolin Chen <redacted>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h   | 28 ++++++++++++
 .../arm/arm-smmu-v3/arm-smmu-v3-iommufd.c     | 45 +++++++++++++++++++
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c   | 18 +++++++-
 3 files changed, 90 insertions(+), 1 deletion(-)

Apologies for my spelling error in [1]. It's supposed to be:

Reviewed-by: Pranjal Shrivastava <praan@google.com>

For all the other patches too. Correct spelling in [2].

Thanks,
Praan

[1] https://lore.kernel.org/all/Z73zvIbsXzJMCaNt@google.com/ (local)
[2] https://lore.kernel.org/all/Z730M3XptvDRObBp@google.com/ (local)