memory: Add RAM_PROTECTED flag to skip IOMMU mappings
Add a new RAMBlock flag to denote "protected" memory, i.e. memory that
looks and acts like RAM but is inaccessible via normal mechanisms,
including DMA. Use the flag to skip protected memory regions when
mapping RAM for DMA in VFIO.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Yang Zhong <yang.zhong@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/include/exec/memory.h b/include/exec/memory.h
index c3d417d..9446874 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -190,6 +190,9 @@
*/
#define RAM_NORESERVE (1 << 7)
+/* RAM that isn't accessible through normal means. */
+#define RAM_PROTECTED (1 << 8)
+
static inline void iommu_notifier_init(IOMMUNotifier *n, IOMMUNotify fn,
IOMMUNotifierFlag flags,
hwaddr start, hwaddr end,
@@ -1267,7 +1270,7 @@
* @name: the name of the region.
* @size: size of the region.
* @ram_flags: RamBlock flags. Supported flags: RAM_SHARED, RAM_PMEM,
- * RAM_NORESERVE.
+ * RAM_NORESERVE, RAM_PROTECTED.
* @fd: the fd to mmap.
* @offset: offset within the file referenced by fd
* @errp: pointer to Error*, to store an error if it happens.
@@ -1569,6 +1572,16 @@
}
/**
+ * memory_region_is_protected: check whether a memory region is protected
+ *
+ * Returns %true if a memory region is protected RAM and cannot be accessed
+ * via standard mechanisms, e.g. DMA.
+ *
+ * @mr: the memory region being queried
+ */
+bool memory_region_is_protected(MemoryRegion *mr);
+
+/**
* memory_region_get_iommu: check whether a memory region is an iommu
*
* Returns pointer to IOMMUMemoryRegion if a memory region is an iommu,
