[Qemu-devel] [RFC 1/7] memory: address_space_iterate

["Dr. David Alan Gilbert (git)" <dgilbert@redhat.com>]

From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>

Iterate through an address space calling a function for each
section.  The iteration is done in order.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
 include/exec/memory.h | 23 +++++++++++++++++++++++
 memory.c              | 22 ++++++++++++++++++++++
 2 files changed, 45 insertions(+)

diff --git a/include/exec/memory.h b/include/exec/memory.h
index 5ed4042f87..f5a9df642e 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -1987,6 +1987,29 @@ address_space_write_cached(MemoryRegionCache *cache, hwaddr addr,
     address_space_write(cache->as, cache->xlat + addr, MEMTXATTRS_UNSPECIFIED, buf, len);
 }
 
+/**
+ * ASIterateCallback: Function type called by address_space_iterate
+ *
+ * Return 0 on success or a negative error code.
+ *
+ * @mrs: Memory region section for this range
+ * @opaque: The opaque value passed in to the iterator.
+ */
+typedef int (*ASIterateCallback)(MemoryRegionSection *mrs, void *opaque);
+
+/**
+ * address_space_iterate: Call the function for each address range in the
+ *                        AddressSpace, in sorted order.
+ *
+ * Return 0 on success or a negative error code.
+ *
+ * @as: Address space to iterate over
+ * @cb: Function to call.  If the function returns none-0 the iteration will
+ *     stop.
+ * @opaque: Value to pass to the function
+ */
+int
+address_space_iterate(AddressSpace *as, ASIterateCallback cb, void *opaque);
 #endif
 
 #endif
diff --git a/memory.c b/memory.c
index e26e5a3b1d..f45137f25e 100644
--- a/memory.c
+++ b/memory.c
@@ -2810,6 +2810,28 @@ void address_space_destroy(AddressSpace *as)
     call_rcu(as, do_address_space_destroy, rcu);
 }
 
+int address_space_iterate(AddressSpace *as, ASIterateCallback cb,
+                          void *opaque)
+{
+    int res = 0;
+    FlatView *fv = address_space_to_flatview(as);
+    FlatRange *range;
+
+    flatview_ref(fv);
+
+    FOR_EACH_FLAT_RANGE(range, fv) {
+        MemoryRegionSection mrs = section_from_flat_range(range, fv);
+        res = cb(&mrs, opaque);
+        if (res) {
+            break;
+        }
+    }
+
+    flatview_unref(fv);
+
+    return res;
+}
+
 static const char *memory_region_type(MemoryRegion *mr)
 {
     if (memory_region_is_ram_device(mr)) {
-- 
2.14.3