@@ -1072,6 +1072,8 @@ static struct iommu_domain *__iommu_domain_alloc(struct bus_type *bus,
domain->ops = bus->iommu_ops;
domain->type = type;
+ spin_lock_init(&domain->reserved_lock);
+ domain->reserved_binding_list = RB_ROOT;
return domain;
}
@@ -24,6 +24,7 @@
#include <linux/of.h>
#include <linux/types.h>
#include <linux/scatterlist.h>
+#include <linux/spinlock.h>
#include <trace/events/iommu.h>
#define IOMMU_READ (1 << 0)
@@ -82,6 +83,11 @@ struct iommu_domain {
void *handler_token;
struct iommu_domain_geometry geometry;
void *iova_cookie;
+ void *reserved_iova_cookie;
+ /* rb tree indexed by PA, for reserved bindings only */
+ struct rb_root reserved_binding_list;
+ /* protects reserved cookie and rbtree manipulation */
+ spinlock_t reserved_lock;
};
enum iommu_cap {
This patch introduces some new fields in the iommu_domain struct, dedicated to reserved iova management. In a similar way as DMA mapping IOVA window, we need to store information related to a reserved IOVA window. The reserved_iova_cookie will store the reserved iova_domain handle. An RB tree indexed by physical address is introduced to store the host physical addresses bound to reserved IOVAs. Those physical addresses will correspond to MSI frame base addresses, also referred to as doorbells. Their number should be quite limited per domain. Also a mutex is introduced to protect accesses to the iova_domain and RB tree. Signed-off-by: Eric Auger <eric.auger@linaro.org> --- v5 -> v6: - initialize reserved_binding_list - use a spinlock instead of a mutex --- drivers/iommu/iommu.c | 2 ++ include/linux/iommu.h | 6 ++++++ 2 files changed, 8 insertions(+)