[PATCH v5 12/17] iommu/arm-smmu-v3: Check that the RID domain is S1 in SVA

[Jason Gunthorpe]

The SVA code only works if the RID domain is a S1 domain and has already
installed the cdtable.

Originally the check for this was in arm_smmu_sva_bind() but when the op
was removed the test didn't get copied over to the new
arm_smmu_sva_set_dev_pasid().

Without the test wrong usage usually will hit a WARN_ON() in
arm_smmu_write_ctx_desc() due to a missing ctx table.

However, the next patches wil change things so that an IDENTITY domain is
not a struct arm_smmu_domain and this will get into memory corruption if
the struct is wrongly casted.

Fail in arm_smmu_sva_set_dev_pasid() if the STE does not have a S1, which
is a proxy for the STE having a pointer to the CD table. Write it in a way
that will be compatible with the next patches.

Fixes: 386fa64fd52b ("arm-smmu-v3/sva: Add SVA domain support")
Reported-by: Shameerali Kolothum Thodi <shameerali.kolothum.thodi at huawei.com>
Closes: https://lore.kernel.org/linux-iommu/2a828e481416405fb3a4cceb9e075a59@huawei.com/
Signed-off-by: Jason Gunthorpe <jgg at nvidia.com>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c
index 05722121f00e70..540f524ecf018b 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c
@@ -387,7 +387,13 @@ static int __arm_smmu_sva_bind(struct device *dev, struct mm_struct *mm)
 	struct arm_smmu_bond *bond;
 	struct arm_smmu_master *master = dev_iommu_priv_get(dev);
 	struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
-	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+	struct arm_smmu_domain *smmu_domain;
+
+	if (!(domain->type & __IOMMU_DOMAIN_PAGING))
+		return -ENODEV;
+	smmu_domain = to_smmu_domain(domain);
+	if (smmu_domain->stage != ARM_SMMU_DOMAIN_S1)
+		return -ENODEV;
 
 	if (!master || !master->sva_enabled)
 		return -ENODEV;
-- 
2.43.0