[Qemu-devel] [PATCH 04/27] add a version number to ram_list

[Juan Quintela <quintela@redhat.com>]

From: Umesh Deshpande <udeshpan@redhat.com>

This will be used to detect if last_block might have become invalid
across different calls to ram_save_live.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Umesh Deshpande <udeshpan@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
 arch_init.c |    6 ++++++
 cpu-all.h   |    1 +
 exec.c      |    4 ++++
 3 files changed, 11 insertions(+)

diff --git a/arch_init.c b/arch_init.c
index 02d36ce..9e05aae 100644
--- a/arch_init.c
+++ b/arch_init.c
@@ -340,6 +340,7 @@ static int save_xbzrle_page(QEMUFile *f, uint8_t *current_data,

 static RAMBlock *last_block;
 static ram_addr_t last_offset;
+static uint32_t last_version;

 /*
  * ram_save_block: Writes a page of memory to the stream f
@@ -496,6 +497,7 @@ static void reset_ram_globals(void)
 {
     last_block = NULL;
     last_offset = 0;
+    last_version = ram_list.version;
     sort_ram_list();
 }

@@ -554,6 +556,10 @@ static int ram_save_iterate(QEMUFile *f, void *opaque)
     int i;
     uint64_t expected_time;

+    if (ram_list.version != last_version) {
+        reset_ram_globals();
+    }
+
     bytes_transferred_last = bytes_transferred;
     bwidth = qemu_get_clock_ns(rt_clock);

diff --git a/cpu-all.h b/cpu-all.h
index ca3bb24..429b2c6 100644
--- a/cpu-all.h
+++ b/cpu-all.h
@@ -486,6 +486,7 @@ typedef struct RAMBlock {

 typedef struct RAMList {
     uint8_t *phys_dirty;
+    uint32_t version;
     QLIST_HEAD(, RAMBlock) blocks_mru;
     QLIST_HEAD(, RAMBlock) blocks;
     uint64_t dirty_pages;
diff --git a/exec.c b/exec.c
index afc472f..ceffa4f 100644
--- a/exec.c
+++ b/exec.c
@@ -2555,6 +2555,8 @@ ram_addr_t qemu_ram_alloc_from_ptr(ram_addr_t size, void *host,
     QLIST_INSERT_HEAD(&ram_list.blocks, new_block, next);
     QLIST_INSERT_HEAD(&ram_list.blocks_mru, new_block, next_mru);

+    ram_list.version++;
+
     ram_list.phys_dirty = g_realloc(ram_list.phys_dirty,
                                        last_ram_offset() >> TARGET_PAGE_BITS);
     cpu_physical_memory_set_dirty_range(new_block->offset, size, 0xff);
@@ -2578,6 +2580,7 @@ void qemu_ram_free_from_ptr(ram_addr_t addr)
         if (addr == block->offset) {
             QLIST_REMOVE(block, next);
             QLIST_REMOVE(block, next_mru);
+            ram_list.version++;
             g_free(block);
             return;
         }
@@ -2592,6 +2595,7 @@ void qemu_ram_free(ram_addr_t addr)
         if (addr == block->offset) {
             QLIST_REMOVE(block, next);
             QLIST_REMOVE(block, next_mru);
+            ram_list.version++;
             if (block->flags & RAM_PREALLOC_MASK) {
                 ;
             } else if (mem_path) {
-- 
1.7.10.4