Commit 5a1c7590 authored by Nicolin Chen's avatar Nicolin Chen Committed by Jason Gunthorpe
Browse files

iommu/arm-smmu-v3: Do not bother impl_ops if IOMMU_VIOMMU_TYPE_ARM_SMMUV3 

When viommu type is IOMMU_VIOMMU_TYPE_ARM_SMMUV3, always return or init the
standard struct arm_vsmmu, instead of going through impl_ops that must have
its own viommu type than the standard IOMMU_VIOMMU_TYPE_ARM_SMMUV3.

Given that arm_vsmmu_init() is called after arm_smmu_get_viommu_size(), any
unsupported viommu->type must be a corruption. And it must be a driver bug
that its vsmmu_size and vsmmu_init ops aren't paired. Warn these two cases.

Link: https://patch.msgid.link/r/20250724221002.1883034-2-nicolinc@nvidia.com


Suggested-by: default avatarWill Deacon <will@kernel.org>
Acked-by: default avatarWill Deacon <will@kernel.org>
Reviewed-by: default avatarPranjal Shrivastava <praan@google.com>
Signed-off-by: default avatarNicolin Chen <nicolinc@nvidia.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
parent ab6bc441

drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c

+16 −11
Original line number Diff line number Diff line
@@ -420,14 +420,13 @@ size_t arm_smmu_get_viommu_size(struct device *dev, 
	    !(smmu->features & ARM_SMMU_FEAT_S2FWB))

		return 0;



	if (smmu->impl_ops && smmu->impl_ops->vsmmu_size &&

	    viommu_type == smmu->impl_ops->vsmmu_type)

		return smmu->impl_ops->vsmmu_size;

	if (viommu_type == IOMMU_VIOMMU_TYPE_ARM_SMMUV3)

		return VIOMMU_STRUCT_SIZE(struct arm_vsmmu, core);



	if (viommu_type != IOMMU_VIOMMU_TYPE_ARM_SMMUV3)

	if (!smmu->impl_ops || !smmu->impl_ops->vsmmu_size ||

	    viommu_type != smmu->impl_ops->vsmmu_type)

		return 0;



	return VIOMMU_STRUCT_SIZE(struct arm_vsmmu, core);

	return smmu->impl_ops->vsmmu_size;

}



int arm_vsmmu_init(struct iommufd_viommu *viommu,
@@ -447,14 +446,20 @@ int arm_vsmmu_init(struct iommufd_viommu *viommu, 
	/* FIXME Move VMID allocation from the S2 domain allocation to here */

	vsmmu->vmid = s2_parent->s2_cfg.vmid;



	if (smmu->impl_ops && smmu->impl_ops->vsmmu_init &&

	    viommu->type == smmu->impl_ops->vsmmu_type)

		return smmu->impl_ops->vsmmu_init(vsmmu, user_data);



	if (viommu->type == IOMMU_VIOMMU_TYPE_ARM_SMMUV3) {

		viommu->ops = &arm_vsmmu_ops;

		return 0;

	}



	/*

	 * Unsupported type should be rejected by arm_smmu_get_viommu_size.

	 * Seeing one here indicates a kernel bug or some data corruption.

	 */

	if (WARN_ON(viommu->type != smmu->impl_ops->vsmmu_type))

		return -EOPNOTSUPP;

	return smmu->impl_ops->vsmmu_init(vsmmu, user_data);

}



int arm_vmaster_report_event(struct arm_smmu_vmaster *vmaster, u64 *evt)

{

	struct iommu_vevent_arm_smmuv3 vevt;

drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c

+14 −0
Original line number Diff line number Diff line
@@ -4703,6 +4703,7 @@ static void arm_smmu_impl_remove(void *data) 
static struct arm_smmu_device *arm_smmu_impl_probe(struct arm_smmu_device *smmu)

{

	struct arm_smmu_device *new_smmu = ERR_PTR(-ENODEV);

	const struct arm_smmu_impl_ops *ops;

	int ret;



	if (smmu->impl_dev && (smmu->options & ARM_SMMU_OPT_TEGRA241_CMDQV))
@@ -4713,11 +4714,24 @@ static struct arm_smmu_device *arm_smmu_impl_probe(struct arm_smmu_device *smmu) 
	if (IS_ERR(new_smmu))

		return new_smmu;



	ops = new_smmu->impl_ops;

	if (ops) {

		/* vsmmu_size and vsmmu_init ops must be paired */

		if (WARN_ON(!ops->vsmmu_size != !ops->vsmmu_init)) {

			ret = -EINVAL;

			goto err_remove;

		}

	}



	ret = devm_add_action_or_reset(new_smmu->dev, arm_smmu_impl_remove,

				       new_smmu);

	if (ret)

		return ERR_PTR(ret);

	return new_smmu;



err_remove:

	arm_smmu_impl_remove(new_smmu);

	return ERR_PTR(ret);

}



static int arm_smmu_device_probe(struct platform_device *pdev)