From 8539c7c16b970258e14761d8a1f7d10fe798031a Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Thu, 26 Mar 2015 13:43:05 +0100 Subject: [PATCH] iommu: Introduce iommu domain types This allows to handle domains differently based on their type in the future. An IOMMU driver can implement certain optimizations for DMA-API domains for example. The domain types can be extended later and some of the existing domain attributes can be migrated to become domain flags. Tested-by: Thierry Reding Tested-by: Heiko Stuebner Reviewed-by: Alex Williamson Acked-by: Will Deacon Signed-off-by: Joerg Roedel --- drivers/iommu/iommu.c | 5 +++-- include/linux/iommu.h | 27 ++++++++++++++++++++++++++- 2 files changed, 29 insertions(+), 3 deletions(-) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 11de2620bbf4..4920605892a3 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -909,14 +909,15 @@ struct iommu_domain *iommu_domain_alloc(struct bus_type *bus) ops = bus->iommu_ops; if (ops->domain_alloc) - domain = ops->domain_alloc(); + domain = ops->domain_alloc(IOMMU_DOMAIN_UNMANAGED); else domain = kzalloc(sizeof(*domain), GFP_KERNEL); if (!domain) return NULL; - domain->ops = bus->iommu_ops; + domain->ops = bus->iommu_ops; + domain->type = IOMMU_DOMAIN_UNMANAGED; if (ops->domain_init && domain->ops->domain_init(domain)) goto out_free; diff --git a/include/linux/iommu.h b/include/linux/iommu.h index 69d1d120c0a3..72d03fe78cf6 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -51,7 +51,32 @@ struct iommu_domain_geometry { bool force_aperture; /* DMA only allowed in mappable range? */ }; +/* Domain feature flags */ +#define __IOMMU_DOMAIN_PAGING (1U << 0) /* Support for iommu_map/unmap */ +#define __IOMMU_DOMAIN_DMA_API (1U << 1) /* Domain for use in DMA-API + implementation */ +#define __IOMMU_DOMAIN_PT (1U << 2) /* Domain is identity mapped */ + +/* + * This are the possible domain-types + * + * IOMMU_DOMAIN_BLOCKED - All DMA is blocked, can be used to isolate + * devices + * IOMMU_DOMAIN_IDENTITY - DMA addresses are system physical addresses + * IOMMU_DOMAIN_UNMANAGED - DMA mappings managed by IOMMU-API user, used + * for VMs + * IOMMU_DOMAIN_DMA - Internally used for DMA-API implementations. + * This flag allows IOMMU drivers to implement + * certain optimizations for these domains + */ +#define IOMMU_DOMAIN_BLOCKED (0U) +#define IOMMU_DOMAIN_IDENTITY (__IOMMU_DOMAIN_PT) +#define IOMMU_DOMAIN_UNMANAGED (__IOMMU_DOMAIN_PAGING) +#define IOMMU_DOMAIN_DMA (__IOMMU_DOMAIN_PAGING | \ + __IOMMU_DOMAIN_DMA_API) + struct iommu_domain { + unsigned type; const struct iommu_ops *ops; void *priv; iommu_fault_handler_t handler; @@ -117,7 +142,7 @@ struct iommu_ops { void (*domain_destroy)(struct iommu_domain *domain); /* Domain allocation and freeing by the iommu driver */ - struct iommu_domain *(*domain_alloc)(void); + struct iommu_domain *(*domain_alloc)(unsigned iommu_domain_type); void (*domain_free)(struct iommu_domain *); int (*attach_dev)(struct iommu_domain *domain, struct device *dev);