Add VMState support for int32_t check value

We read the saved value and check that it is the same that the one
is stored in the structure.
Signed-off-by: NJuan Quintela <quintela@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

hw/hw.h

@@ -311,6 +311,8 @@ extern const VMStateInfo vmstate_info_int16;
 extern const VMStateInfo vmstate_info_int32;
 extern const VMStateInfo vmstate_info_int64;
 
+extern const VMStateInfo vmstate_info_int32_equal;
+
 extern const VMStateInfo vmstate_info_uint8;
 extern const VMStateInfo vmstate_info_uint16;
 extern const VMStateInfo vmstate_info_uint32;
@@ -414,6 +416,9 @@ extern const VMStateInfo vmstate_info_timer;
 #define VMSTATE_UINT64(_f, _s)                                        \
     VMSTATE_UINT64_V(_f, _s, 0)
 
+#define VMSTATE_INT32_EQUAL(_f, _s)                                   \
+    VMSTATE_SINGLE(_f, _s, 0, vmstate_info_int32_equal, int32_t)
+
 #define VMSTATE_TIMER_V(_f, _s, _v)                                   \
     VMSTATE_POINTER(_f, _s, _v, vmstate_info_timer, QEMUTimer *)
 

savevm.c

@@ -702,6 +702,26 @@ const VMStateInfo vmstate_info_int32 = {
     .put  = put_int32,
 };
 
+/* 32 bit int. See that the received value is the same than the one
+   in the field */
+
+static int get_int32_equal(QEMUFile *f, void *pv, size_t size)
+{
+    int32_t *v = pv;
+    int32_t v2;
+    qemu_get_sbe32s(f, &v2);
+
+    if (*v == v2)
+        return 0;
+    return -EINVAL;
+}
+
+const VMStateInfo vmstate_info_int32_equal = {
+    .name = "int32 equal",
+    .get  = get_int32_equal,
+    .put  = put_int32,
+};
+
 /* 64 bit int */
 
 static int get_int64(QEMUFile *f, void *pv, size_t size)