[PATCH for-rc] iommu/amd: Add missing domain type checks

[Jason Gunthorpe <jgg@nvidia.com>]

Drivers are supposed to list the domain types they support in their
domain_alloc() ops so when we add new domain types, like BLOCKING or SVA,
they don't start breaking.

This ended up providing an empty UNMANAGED domain when the core code asked
for a BLOCKING domain, which happens to be the fallback for drivers that
don't support it, but this is completely wrong for SVA.

Check for the DMA types AMD supports and reject every other kind.

Fixes: 136467962e49 ("iommu: Add IOMMU SVA domain support")
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
---
 drivers/iommu/amd/iommu.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index c72a0173db2029..17ea44a79c7af9 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -2067,7 +2067,7 @@ static struct protection_domain *protection_domain_alloc(unsigned int type)
 {
 	struct io_pgtable_ops *pgtbl_ops;
 	struct protection_domain *domain;
-	int pgtable = amd_iommu_pgtable;
+	int pgtable;
 	int mode = DEFAULT_PGTABLE_LEVEL;
 	int ret;
 
@@ -2084,6 +2084,10 @@ static struct protection_domain *protection_domain_alloc(unsigned int type)
 		mode = PAGE_MODE_NONE;
 	} else if (type == IOMMU_DOMAIN_UNMANAGED) {
 		pgtable = AMD_IOMMU_V1;
+	} else if (type == IOMMU_DOMAIN_DMA || type == IOMMU_DOMAIN_DMA_FQ) {
+		pgtable = amd_iommu_pgtable;
+	} else {
+		return NULL;
 	}
 
 	switch (pgtable) {

base-commit: 4f933b868392945c9b0e32b499b0bb39beab8a28
-- 
2.40.0