[PATCH QEMU v22 11/18] iommu: add callback to get address limit IOMMU supports

[Kirti Wankhede <kwankhede@nvidia.com>]

Add optional method to get address limit IOMMU supports

Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
---
 hw/i386/intel_iommu.c |  9 +++++++++
 include/exec/memory.h | 18 ++++++++++++++++++
 memory.c              | 11 +++++++++++
 3 files changed, 38 insertions(+)

diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index df7ad254ac15..d0b88c20c31e 100644
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -3577,6 +3577,14 @@ static void vtd_iommu_replay(IOMMUMemoryRegion *iommu_mr, IOMMUNotifier *n)
     return;
 }
 
+static hwaddr vtd_iommu_get_address_limit(IOMMUMemoryRegion *iommu_mr)
+{
+    VTDAddressSpace *vtd_as = container_of(iommu_mr, VTDAddressSpace, iommu);
+    IntelIOMMUState *s = vtd_as->iommu_state;
+
+    return VTD_ADDRESS_SIZE(s->aw_bits) - 1;
+}
+
 /* Do the initialization. It will also be called when reset, so pay
  * attention when adding new initialization stuff.
  */
@@ -3878,6 +3886,7 @@ static void vtd_iommu_memory_region_class_init(ObjectClass *klass,
     imrc->translate = vtd_iommu_translate;
     imrc->notify_flag_changed = vtd_iommu_notify_flag_changed;
     imrc->replay = vtd_iommu_replay;
+    imrc->get_address_limit = vtd_iommu_get_address_limit;
 }
 
 static const TypeInfo vtd_iommu_memory_region_info = {
diff --git a/include/exec/memory.h b/include/exec/memory.h
index e000bd2f97b2..2d0cbd46d2a6 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -355,6 +355,16 @@ typedef struct IOMMUMemoryRegionClass {
      * @iommu: the IOMMUMemoryRegion
      */
     int (*num_indexes)(IOMMUMemoryRegion *iommu);
+
+    /*
+     * Return address limit this IOMMU supports.
+     *
+     * Optional method: if this method is not provided, then
+     * memory_region_iommu_get_address_limit() will return 0.
+     *
+     * @iommu: the IOMMUMemoryRegion
+     */
+    hwaddr (*get_address_limit)(IOMMUMemoryRegion *iommu);
 } IOMMUMemoryRegionClass;
 
 typedef struct CoalescedMemoryRange CoalescedMemoryRange;
@@ -1364,6 +1374,14 @@ int memory_region_iommu_attrs_to_index(IOMMUMemoryRegion *iommu_mr,
 int memory_region_iommu_num_indexes(IOMMUMemoryRegion *iommu_mr);
 
 /**
+ * memory_region_iommu_get_address_limit : return the maximum address limit
+ * that this IOMMU supports.
+ *
+ * @iommu_mr: the memory region
+ */
+hwaddr memory_region_iommu_get_address_limit(IOMMUMemoryRegion *iommu_mr);
+
+/**
  * memory_region_name: get a memory region's name
  *
  * Returns the string that was used to initialize the memory region.
diff --git a/memory.c b/memory.c
index 601b74990620..52f1a4cd37f0 100644
--- a/memory.c
+++ b/memory.c
@@ -1887,6 +1887,17 @@ void memory_region_iommu_replay(IOMMUMemoryRegion *iommu_mr, IOMMUNotifier *n)
     }
 }
 
+hwaddr memory_region_iommu_get_address_limit(IOMMUMemoryRegion *iommu_mr)
+{
+    IOMMUMemoryRegionClass *imrc = IOMMU_MEMORY_REGION_GET_CLASS(iommu_mr);
+
+    if (imrc->get_address_limit) {
+        return imrc->get_address_limit(iommu_mr);
+    }
+
+    return 0;
+}
+
 void memory_region_unregister_iommu_notifier(MemoryRegion *mr,
                                              IOMMUNotifier *n)
 {
-- 
2.7.0