@@ -1644,6 +1644,17 @@ iommu_group_alloc_default_domain(struct iommu_group *group, int req_type)
lockdep_assert_held(&group->mutex);
+ /*
+ * Allow legacy drivers to specify the domain that will be the default
+ * domain. This should always be either an IDENTITY or PLATFORM domain.
+ * Do not use in new drivers.
+ */
+ if (bus->iommu_ops->default_domain) {
+ if (req_type)
+ return ERR_PTR(-EINVAL);
+ return bus->iommu_ops->default_domain;
+ }
+
if (req_type)
return __iommu_group_alloc_default_domain(bus, group, req_type);
@@ -1952,7 +1963,8 @@ void iommu_domain_free(struct iommu_domain *domain)
if (domain->type == IOMMU_DOMAIN_SVA)
mmdrop(domain->mm);
iommu_put_dma_cookie(domain);
- domain->ops->free(domain);
+ if (domain->ops->free)
+ domain->ops->free(domain);
}
EXPORT_SYMBOL_GPL(iommu_domain_free);
@@ -64,6 +64,7 @@ struct iommu_domain_geometry {
#define __IOMMU_DOMAIN_DMA_FQ (1U << 3) /* DMA-API uses flush queue */
#define __IOMMU_DOMAIN_SVA (1U << 4) /* Shared process address space */
+#define __IOMMU_DOMAIN_PLATFORM (1U << 5)
/*
* This are the possible domain-types
@@ -80,6 +81,8 @@ struct iommu_domain_geometry {
* invalidation.
* IOMMU_DOMAIN_SVA - DMA addresses are shared process addresses
* represented by mm_struct's.
+ * IOMMU_DOMAIN_PLATFORM - Legacy domain for drivers that do their own
+ * dma_api stuff. Do not use in new drivers.
*/
#define IOMMU_DOMAIN_BLOCKED (0U)
#define IOMMU_DOMAIN_IDENTITY (__IOMMU_DOMAIN_PT)
@@ -90,6 +93,7 @@ struct iommu_domain_geometry {
__IOMMU_DOMAIN_DMA_API | \
__IOMMU_DOMAIN_DMA_FQ)
#define IOMMU_DOMAIN_SVA (__IOMMU_DOMAIN_SVA)
+#define IOMMU_DOMAIN_PLATFORM (__IOMMU_DOMAIN_PLATFORM)
struct iommu_domain {
unsigned type;
@@ -250,6 +254,7 @@ struct iommu_iotlb_gather {
* @owner: Driver module providing these ops
* @identity_domain: An always available, always attachable identity
* translation.
+ * @default_domain: If not NULL this will always be set as the default domain.
*/
struct iommu_ops {
bool (*capable)(struct device *dev, enum iommu_cap);
@@ -284,6 +289,7 @@ struct iommu_ops {
unsigned long pgsize_bitmap;
struct module *owner;
struct iommu_domain *identity_domain;
+ struct iommu_domain *default_domain;
};
/**
This is used when the iommu driver is taking control of the dma_ops, currently only on S390 and power spapr. It is designed to preserve the original ops->detach_dev() semantic that these S390 was built around. Provide an opaque domain type and a 'default_domain' ops value that allows the driver to trivially force any single domain as the default domain. Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> --- drivers/iommu/iommu.c | 14 +++++++++++++- include/linux/iommu.h | 6 ++++++ 2 files changed, 19 insertions(+), 1 deletion(-)