iommu: Introduce iommu_capable API function

This function will replace the current iommu_domain_has_cap
function and clean up the interface while at it.

Signed-off-by: Joerg Roedel <jroedel@suse.de>

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index bc45478e26db76d55eef533cbb528586998d5d44..aeb243f46332815f21a042d228930deb72eb2c1b 100644 (file)
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -817,6 +817,15 @@ bool iommu_present(struct bus_type *bus)
 }
 EXPORT_SYMBOL_GPL(iommu_present);
 
+bool iommu_capable(struct bus_type *bus, enum iommu_cap cap)
+{
+       if (!bus->iommu_ops || !bus->iommu_ops->capable)
+               return false;
+
+       return bus->iommu_ops->capable(cap);
+}
+EXPORT_SYMBOL_GPL(iommu_capable);
+
 /**
  * iommu_set_fault_handler() - set a fault handler for an iommu domain
  * @domain: iommu domain
@@ -950,10 +959,13 @@ EXPORT_SYMBOL_GPL(iommu_iova_to_phys);
 int iommu_domain_has_cap(struct iommu_domain *domain,
                         enum iommu_cap cap)
 {
-       if (unlikely(domain->ops->domain_has_cap == NULL))
-               return 0;
+       if (domain->ops->domain_has_cap != NULL)
+               return domain->ops->domain_has_cap(domain, cap);
+
+       if (domain->ops->capable != NULL)
+               return domain->ops->capable(cap);
 
-       return domain->ops->domain_has_cap(domain, cap);
+       return 0;
 }
 EXPORT_SYMBOL_GPL(iommu_domain_has_cap);
 

diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 98fc126655ae2bafefcac775bd019e74d02982a3..d5534d554693a02ae37934e25ace44f4cceedba8 100644 (file)
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -105,6 +105,7 @@ enum iommu_attr {
  * @pgsize_bitmap: bitmap of supported page sizes
  */
 struct iommu_ops {
+       bool (*capable)(enum iommu_cap);
        int (*domain_init)(struct iommu_domain *domain);
        void (*domain_destroy)(struct iommu_domain *domain);
        int (*attach_dev)(struct iommu_domain *domain, struct device *dev);
@@ -145,6 +146,7 @@ struct iommu_ops {
 
 extern int bus_set_iommu(struct bus_type *bus, const struct iommu_ops *ops);
 extern bool iommu_present(struct bus_type *bus);
+extern bool iommu_capable(struct bus_type *bus, enum iommu_cap cap);
 extern struct iommu_domain *iommu_domain_alloc(struct bus_type *bus);
 extern struct iommu_group *iommu_group_get_by_id(int id);
 extern void iommu_domain_free(struct iommu_domain *domain);
@@ -253,6 +255,11 @@ static inline bool iommu_present(struct bus_type *bus)
        return false;
 }
 
+static inline bool iommu_capable(struct bus_type *bus, enum iommu_cap cap)
+{
+       return false;
+}
+
 static inline struct iommu_domain *iommu_domain_alloc(struct bus_type *bus)
 {
        return NULL;