1 files changed, 40 insertions, 3 deletions

diff --git a/migration/ram.c b/migration/ram.c
index cd7a446c95..404c8f0853 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -3458,6 +3458,15 @@ static inline void *colo_cache_from_block_offset(RAMBlock *block,
                      __func__, block->idstr);
         return NULL;
     }
+
+    /*
+    * During colo checkpoint, we need bitmap of these migrated pages.
+    * It help us to decide which pages in ram cache should be flushed
+    * into VM's RAM later.
+    */
+    if (!test_and_set_bit(offset >> TARGET_PAGE_BITS, block->bmap)) {
+        ram_state->migration_dirty_pages++;
+    }
     return block->colo_cache + offset;
 }
 
@@ -3675,7 +3684,7 @@ int colo_init_ram_cache(void)
     RAMBlock *block;
 
     rcu_read_lock();
-    QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
+    RAMBLOCK_FOREACH_MIGRATABLE(block) {
         block->colo_cache = qemu_anon_ram_alloc(block->used_length,
                                                 NULL,
                                                 false);
@@ -3688,10 +3697,29 @@ int colo_init_ram_cache(void)
         memcpy(block->colo_cache, block->host, block->used_length);
     }
     rcu_read_unlock();
+    /*
+    * Record the dirty pages that sent by PVM, we use this dirty bitmap together
+    * with to decide which page in cache should be flushed into SVM's RAM. Here
+    * we use the same name 'ram_bitmap' as for migration.
+    */
+    if (ram_bytes_total()) {
+        RAMBlock *block;
+
+        RAMBLOCK_FOREACH_MIGRATABLE(block) {
+            unsigned long pages = block->max_length >> TARGET_PAGE_BITS;
+
+            block->bmap = bitmap_new(pages);
+            bitmap_set(block->bmap, 0, pages);
+        }
+    }
+    ram_state = g_new0(RAMState, 1);
+    ram_state->migration_dirty_pages = 0;
+
     return 0;
 
 out_locked:
-    QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
+
+    RAMBLOCK_FOREACH_MIGRATABLE(block) {
         if (block->colo_cache) {
             qemu_anon_ram_free(block->colo_cache, block->used_length);
             block->colo_cache = NULL;
@@ -3707,14 +3735,23 @@ void colo_release_ram_cache(void)
 {
     RAMBlock *block;
 
+    RAMBLOCK_FOREACH_MIGRATABLE(block) {
+        g_free(block->bmap);
+        block->bmap = NULL;
+    }
+
     rcu_read_lock();
-    QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
+
+    RAMBLOCK_FOREACH_MIGRATABLE(block) {
         if (block->colo_cache) {
             qemu_anon_ram_free(block->colo_cache, block->used_length);
             block->colo_cache = NULL;
         }
     }
+
     rcu_read_unlock();
+    g_free(ram_state);
+    ram_state = NULL;
 }
 
 /**