1 files changed, 44 insertions, 0 deletions
diff --git a/system/physmem.c b/system/physmem.c
index 36f327ca94..3d81272f9f 100644
--- a/system/physmem.c
+++ b/system/physmem.c
@@ -899,6 +899,50 @@ void tlb_reset_dirty_range_all(ram_addr_t start, ram_addr_t length)
     }
 }
 
+static bool physical_memory_get_dirty(ram_addr_t start, ram_addr_t length,
+                                      unsigned client)
+{
+    DirtyMemoryBlocks *blocks;
+    unsigned long end, page;
+    unsigned long idx, offset, base;
+    bool dirty = false;
+
+    assert(client < DIRTY_MEMORY_NUM);
+
+    end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
+    page = start >> TARGET_PAGE_BITS;
+
+    WITH_RCU_READ_LOCK_GUARD() {
+        blocks = qatomic_rcu_read(&ram_list.dirty_memory[client]);
+
+        idx = page / DIRTY_MEMORY_BLOCK_SIZE;
+        offset = page % DIRTY_MEMORY_BLOCK_SIZE;
+        base = page - offset;
+        while (page < end) {
+            unsigned long next = MIN(end, base + DIRTY_MEMORY_BLOCK_SIZE);
+            unsigned long num = next - base;
+            unsigned long found = find_next_bit(blocks->blocks[idx],
+                                                num, offset);
+            if (found < num) {
+                dirty = true;
+                break;
+            }
+
+            page = next;
+            idx++;
+            offset = 0;
+            base += DIRTY_MEMORY_BLOCK_SIZE;
+        }
+    }
+
+    return dirty;
+}
+
+bool cpu_physical_memory_get_dirty_flag(ram_addr_t addr, unsigned client)
+{
+    return physical_memory_get_dirty(addr, 1, client);
+}
+
 /* Note: start and end must be within the same ram block.  */
 bool cpu_physical_memory_test_and_clear_dirty(ram_addr_t start,
                                               ram_addr_t length,