Flush IO requests before savevm (original patch by Blue Swirl).

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@2140 c046a42c-6fe2-441c-8c8c-71466251a162

block-raw.c

@@ -247,6 +247,17 @@ void qemu_aio_poll(void)
  the_end: ;
 }
 
+/* Wait for all IO requests to complete.  */
+void qemu_aio_flush(void)
+{
+    qemu_aio_wait_start();
+    qemu_aio_poll();
+    while (first_aio) {
+        qemu_aio_wait();
+    }
+    qemu_aio_wait_end();
+}
+
 /* wait until at least one AIO was handled */
 static sigset_t wait_oset;
 

vl.c

@@ -4551,6 +4551,9 @@ void do_savevm(const char *name)
         return;
     }
 
+    /* ??? Should this occur after vm_stop?  */
+    qemu_aio_flush();
+
     saved_vm_running = vm_running;
     vm_stop(0);
     
@@ -4641,6 +4644,9 @@ void do_loadvm(const char *name)
         return;
     }
     
+    /* Flush all IO requests so they don't interfere with the new state.  */
+    qemu_aio_flush();
+
     saved_vm_running = vm_running;
     vm_stop(0);
 

vl.h

@@ -580,6 +580,7 @@ void bdrv_aio_cancel(BlockDriverAIOCB *acb);
 
 void qemu_aio_init(void);
 void qemu_aio_poll(void);
+void qemu_aio_flush(void);
 void qemu_aio_wait_start(void);
 void qemu_aio_wait(void);
 void qemu_aio_wait_end(void);