iommu-api: Add iommu_map and iommu_unmap functions

These two functions provide support for mapping and
unmapping physical addresses to io virtual addresses. The
difference to the iommu_(un)map_range() is that the new
functions take a gfp_order parameter instead of a size. This
allows the IOMMU backend implementations to detect easier if
a given range can be mapped by larger page sizes.
These new functions should replace the old ones in the long
term.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

drivers/base/iommu.c

@@ -107,3 +107,34 @@ int iommu_domain_has_cap(struct iommu_domain *domain,
 	return iommu_ops->domain_has_cap(domain, cap);
 }
 EXPORT_SYMBOL_GPL(iommu_domain_has_cap);
+
+int iommu_map(struct iommu_domain *domain, unsigned long iova,
+	      phys_addr_t paddr, int gfp_order, int prot)
+{
+	unsigned long invalid_mask;
+	size_t size;
+
+	size         = 0x1000UL << gfp_order;
+	invalid_mask = size - 1;
+
+	BUG_ON((iova | paddr) & invalid_mask);
+
+	return iommu_ops->map_range(domain, iova, paddr, size, prot);
+}
+EXPORT_SYMBOL_GPL(iommu_map);
+
+int iommu_unmap(struct iommu_domain *domain, unsigned long iova, int gfp_order)
+{
+	unsigned long invalid_mask;
+	size_t size;
+
+	size         = 0x1000UL << gfp_order;
+	invalid_mask = size - 1;
+
+	BUG_ON(iova & invalid_mask);
+
+	iommu_ops->unmap_range(domain, iova, size);
+
+	return gfp_order;
+}
+EXPORT_SYMBOL_GPL(iommu_unmap);

include/linux/iommu.h

@@ -60,6 +60,10 @@ extern int iommu_map_range(struct iommu_domain *domain, unsigned long iova,
 			   phys_addr_t paddr, size_t size, int prot);
 extern void iommu_unmap_range(struct iommu_domain *domain, unsigned long iova,
 			      size_t size);
+extern int iommu_map(struct iommu_domain *domain, unsigned long iova,
+		     phys_addr_t paddr, int gfp_order, int prot);
+extern int iommu_unmap(struct iommu_domain *domain, unsigned long iova,
+		       int gfp_order);
 extern phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain,
 				      unsigned long iova);
 extern int iommu_domain_has_cap(struct iommu_domain *domain,
@@ -108,6 +112,18 @@ static inline void iommu_unmap_range(struct iommu_domain *domain,
 {
 }
 
+static inline int iommu_map(struct iommu_domain *domain, unsigned long iova,
+			    phys_addr_t paddr, int gfp_order, int prot)
+{
+	return -ENODEV;
+}
+
+static inline int iommu_unmap(struct iommu_domain *domain, unsigned long iova,
+			      int gfp_order)
+{
+	return -ENODEV;
+}
+
 static inline phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain,
 					     unsigned long iova)
 {