Signed-off-by: Paolo Bonzini pbonz...@redhat.com
---
include/exec/memory.h | 34 ++
memory.c | 14 ++
2 files changed, 48 insertions(+), 0 deletions(-)
diff --git a/include/exec/memory.h b/include/exec/memory.h
index 5c20bac..ebac085 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -253,6 +253,40 @@ struct MemoryListener {
void memory_region_init(MemoryRegion *mr,
const char *name,
uint64_t size);
+
+/**
+ * memory_region_ref: Add 1 to a memory region's reference count
+ *
+ * Whenever memory regions are accessed outside the BQL, they need to be
+ * preserved against hot-unplug. MemoryRegions actually do not have their
+ * own reference count; they piggyback on a QOM object, their owner.
+ * This function adds a reference to the owner.
+ *
+ * All MemoryRegions must have an owner if they can disappear, even if the
+ * device they belong to operates exclusively under the BQL. This is because
+ * the region could be returned at any time by memory_region_find, and this
+ * is usually under guest control.
+ *
+ * @mr: the #MemoryRegion to be initialized
+ * @name: used for debugging; not visible to the user or ABI
+ * @size: size of the region; any subregions beyond this size will be clipped
+ */
+void memory_region_ref(MemoryRegion *mr);
+
+/**
+ * memory_region_ref: Remove 1 to a memory region's reference count
+ *
+ * Whenever memory regions are accessed outside the BQL, they need to be
+ * preserved against hot-unplug. MemoryRegions actually do not have their
+ * own reference count; they piggyback on a QOM object, their owner.
+ * This function removes a reference to the owner and possibly destroys it.
+ *
+ * @mr: the #MemoryRegion to be initialized
+ * @name: used for debugging; not visible to the user or ABI
+ * @size: size of the region; any subregions beyond this size will be clipped
+ */
+void memory_region_unref(MemoryRegion *mr);
+
/**
* memory_region_init_io: Initialize an I/O memory region.
*
diff --git a/memory.c b/memory.c
index f7fddb1..c7ab19c 100644
--- a/memory.c
+++ b/memory.c
@@ -1061,6 +1061,20 @@ void memory_region_set_owner(MemoryRegion *mr,
}
}
+void memory_region_ref(MemoryRegion *mr)
+{
+if (mr mr-owner) {
+object_ref(mr-owner);
+}
+}
+
+void memory_region_unref(MemoryRegion *mr)
+{
+if (mr mr-owner) {
+object_unref(mr-owner);
+}
+}
+
uint64_t memory_region_size(MemoryRegion *mr)
{
if (int128_eq(mr-size, int128_2_64())) {
--
1.7.1
