Re: [PATCH v8 12/14] iommu/arm-smmu-v3: Introduce struct arm_smmu_vmaster
From: Will Deacon <will@kernel.org>
Date: 2025-03-11 15:57:23
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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.
"fenche"?
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
s/point/pointer/
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>
(per Pranjal: please fix his mis-spelling of his own name here and in the other patches too!)
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(-)
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@@ -1055,9 +1062,30 @@ struct iommufd_viommu *arm_vsmmu_alloc(struct device *dev, struct iommu_domain *parent, struct iommufd_ctx *ictx, unsigned int viommu_type); +int arm_smmu_attach_prepare_vmaster(struct arm_smmu_attach_state *state, + struct arm_smmu_nested_domain *nested_domain); +void arm_smmu_attach_commit_vmaster(struct arm_smmu_attach_state *state); +void arm_smmu_master_clear_vmaster(struct arm_smmu_master *master); #else #define arm_smmu_hw_info NULL #define arm_vsmmu_alloc NULL + +static inline int +arm_smmu_attach_prepare_vmaster(struct arm_smmu_attach_state *state, + struct arm_smmu_nested_domain *nested_domain) +{ + return 0; /* NOP */ +}
Please drop this comment.
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diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c index 5aa2e7af58b4..6b712b1ab429 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c@@ -85,6 +85,51 @@ static void arm_smmu_make_nested_domain_ste( } } +int arm_smmu_attach_prepare_vmaster(struct arm_smmu_attach_state *state, + struct arm_smmu_nested_domain *nested_domain) +{ + struct arm_smmu_vmaster *vmaster; + unsigned long vsid; + int ret; + + iommu_group_mutex_assert(state->master->dev); + + /* Skip invalid vSTE */ + if (!(nested_domain->ste[0] & cpu_to_le64(STRTAB_STE_0_V))) + return 0;
Ok, and we don't need to set 'state->vmaster' in this case because we only report stage-1 faults back to the vSMMU? With the nits fixed: Acked-by: Will Deacon <will@kernel.org> Thanks, Will