[PATCH v4 09/12] iommu/amd: Enhance amd_iommu_domain_alloc_user()

[Vasant Hegde <vasant.hegde@amd.com>]

Previous patch enhanced core layer to check device PASID capability and
pass right flags to ops->domain_alloc_user().

Enhance amd_iommu_domain_alloc_user() to allocate domain with
appropriate page table based on flags parameter.
  - If flags is empty then allocate domain with default page table type.
    This will eventually replace ops->domain_alloc().
    For UNMANAGED domain, core will call this interface with flags=0. So
    AMD driver will continue to allocate V1 page table.

  - If IOMMU_HWPT_ALLOC_PASID flags is passed then allocate domain with v2
    page table.

Signed-off-by: Vasant Hegde <vasant.hegde@amd.com>
---
 drivers/iommu/amd/iommu.c | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index cb6a72564c23..cdc93c794eff 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -2403,10 +2403,26 @@ amd_iommu_domain_alloc_user(struct device *dev, u32 flags,
 
 {
 	unsigned int type = IOMMU_DOMAIN_UNMANAGED;
+	const u32 supported_flags = IOMMU_HWPT_ALLOC_DIRTY_TRACKING |
+						IOMMU_HWPT_ALLOC_PASID;
 
-	if ((flags & ~IOMMU_HWPT_ALLOC_DIRTY_TRACKING) || parent || user_data)
+	if ((flags & ~supported_flags) || parent || user_data)
 		return ERR_PTR(-EOPNOTSUPP);
 
+	/* Allocate domain with default page table */
+	if (!flags) {
+		return do_iommu_domain_alloc(IOMMU_DOMAIN_DMA,
+					     dev, 0, amd_iommu_pgtable);
+	}
+
+	/* Allocate domain with v2 page table if IOMMU supports PASID. */
+	if (flags & IOMMU_HWPT_ALLOC_PASID) {
+		if (!amd_iommu_pasid_supported())
+			return ERR_PTR(-EOPNOTSUPP);
+
+		return do_iommu_domain_alloc(type, dev, flags, AMD_IOMMU_V2);
+	}
+
 	return do_iommu_domain_alloc(type, dev, flags, AMD_IOMMU_V1);
 }
 
-- 
2.31.1