[Qemu-devel] [PATCH 1/5] migration/ram.c: Use RAMBlock rather than MemoryRegion

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

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

RAM migration mainly works on RAMBlocks but in a few places
uses data from MemoryRegions to access the same information that's
already held in RAMBlocks; clean it up just to avoid the
MemoryRegion use.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
 migration/ram.c | 26 +++++++++++---------------
 1 file changed, 11 insertions(+), 15 deletions(-)

diff --git a/migration/ram.c b/migration/ram.c
index 7f007e6..7df9157 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -497,13 +497,13 @@ static int save_xbzrle_page(QEMUFile *f, uint8_t **current_data,
 
 /* Called with rcu_read_lock() to protect migration_bitmap */
 static inline
-ram_addr_t migration_bitmap_find_and_reset_dirty(MemoryRegion *mr,
+ram_addr_t migration_bitmap_find_and_reset_dirty(RAMBlock *rb,
                                                  ram_addr_t start)
 {
-    unsigned long base = mr->ram_addr >> TARGET_PAGE_BITS;
+    unsigned long base = rb->offset >> TARGET_PAGE_BITS;
     unsigned long nr = base + (start >> TARGET_PAGE_BITS);
-    uint64_t mr_size = TARGET_PAGE_ALIGN(memory_region_size(mr));
-    unsigned long size = base + (mr_size >> TARGET_PAGE_BITS);
+    uint64_t rb_size = rb->used_length;
+    unsigned long size = base + (rb_size >> TARGET_PAGE_BITS);
     unsigned long *bitmap;
 
     unsigned long next;
@@ -573,7 +573,7 @@ static void migration_bitmap_sync(void)
     qemu_mutex_lock(&migration_bitmap_mutex);
     rcu_read_lock();
     QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
-        migration_bitmap_sync_range(block->mr->ram_addr, block->used_length);
+        migration_bitmap_sync_range(block->offset, block->used_length);
     }
     rcu_read_unlock();
     qemu_mutex_unlock(&migration_bitmap_mutex);
@@ -668,12 +668,11 @@ static int ram_save_page(QEMUFile *f, RAMBlock* block, ram_addr_t offset,
     int pages = -1;
     uint64_t bytes_xmit;
     ram_addr_t current_addr;
-    MemoryRegion *mr = block->mr;
     uint8_t *p;
     int ret;
     bool send_async = true;
 
-    p = memory_region_get_ram_ptr(mr) + offset;
+    p = block->host + offset;
 
     /* In doubt sent page as normal */
     bytes_xmit = 0;
@@ -744,7 +743,7 @@ static int do_compress_ram_page(CompressParam *param)
     RAMBlock *block = param->block;
     ram_addr_t offset = param->offset;
 
-    p = memory_region_get_ram_ptr(block->mr) + (offset & TARGET_PAGE_MASK);
+    p = block->host + (offset & TARGET_PAGE_MASK);
 
     bytes_sent = save_page_header(param->file, block, offset |
                                   RAM_SAVE_FLAG_COMPRESS_PAGE);
@@ -852,11 +851,10 @@ static int ram_save_compressed_page(QEMUFile *f, RAMBlock *block,
 {
     int pages = -1;
     uint64_t bytes_xmit;
-    MemoryRegion *mr = block->mr;
     uint8_t *p;
     int ret;
 
-    p = memory_region_get_ram_ptr(mr) + offset;
+    p = block->host + offset;
 
     bytes_xmit = 0;
     ret = ram_control_save_page(f, block->offset,
@@ -929,14 +927,12 @@ static int ram_find_and_save_block(QEMUFile *f, bool last_stage,
     ram_addr_t offset = last_offset;
     bool complete_round = false;
     int pages = 0;
-    MemoryRegion *mr;
 
     if (!block)
         block = QLIST_FIRST_RCU(&ram_list.blocks);
 
     while (true) {
-        mr = block->mr;
-        offset = migration_bitmap_find_and_reset_dirty(mr, offset);
+        offset = migration_bitmap_find_and_reset_dirty(block, offset);
         if (complete_round && block == last_seen_block &&
             offset >= last_offset) {
             break;
@@ -1344,7 +1340,7 @@ static inline void *host_from_stream_offset(QEMUFile *f,
             return NULL;
         }
 
-        return memory_region_get_ram_ptr(block->mr) + offset;
+        return block->host + offset;
     }
 
     len = qemu_get_byte(f);
@@ -1354,7 +1350,7 @@ static inline void *host_from_stream_offset(QEMUFile *f,
     QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
         if (!strncmp(id, block->idstr, sizeof(id)) &&
             block->max_length > offset) {
-            return memory_region_get_ram_ptr(block->mr) + offset;
+            return block->host + offset;
         }
     }
 
-- 
2.4.3