1 files changed, 60 insertions, 0 deletions
diff --git a/system/physmem.c b/system/physmem.c
index e555b3196f..144fd7303b 100644
--- a/system/physmem.c
+++ b/system/physmem.c
@@ -952,6 +952,66 @@ bool cpu_physical_memory_is_clean(ram_addr_t addr)
     return !(vga && code && migration);
 }
 
+static bool physical_memory_all_dirty(ram_addr_t start, ram_addr_t length,
+                                      unsigned client)
+{
+    DirtyMemoryBlocks *blocks;
+    unsigned long end, page;
+    unsigned long idx, offset, base;
+    bool dirty = true;
+
+    assert(client < DIRTY_MEMORY_NUM);
+
+    end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
+    page = start >> TARGET_PAGE_BITS;
+
+    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_zero_bit(blocks->blocks[idx],
+                                                 num, offset);
+        if (found < num) {
+            dirty = false;
+            break;
+        }
+
+        page = next;
+        idx++;
+        offset = 0;
+        base += DIRTY_MEMORY_BLOCK_SIZE;
+    }
+
+    return dirty;
+}
+
+uint8_t cpu_physical_memory_range_includes_clean(ram_addr_t start,
+                                                 ram_addr_t length,
+                                                 uint8_t mask)
+{
+    uint8_t ret = 0;
+
+    if (mask & (1 << DIRTY_MEMORY_VGA) &&
+        !physical_memory_all_dirty(start, length, DIRTY_MEMORY_VGA)) {
+        ret |= (1 << DIRTY_MEMORY_VGA);
+    }
+    if (mask & (1 << DIRTY_MEMORY_CODE) &&
+        !physical_memory_all_dirty(start, length, DIRTY_MEMORY_CODE)) {
+        ret |= (1 << DIRTY_MEMORY_CODE);
+    }
+    if (mask & (1 << DIRTY_MEMORY_MIGRATION) &&
+        !physical_memory_all_dirty(start, length, DIRTY_MEMORY_MIGRATION)) {
+        ret |= (1 << DIRTY_MEMORY_MIGRATION);
+    }
+    return ret;
+}
+
 /* 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,