Add VMState support for static sized buffers (uint_8)

This patch adds support for static sized buffer and typecheks that the buffer is right.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
diff --git a/hw/hw.h b/hw/hw.h
index 874fe98..02392ca 100644
--- a/hw/hw.h
+++ b/hw/hw.h
@@ -285,6 +285,7 @@
     VMS_ARRAY   = 0x004,
     VMS_STRUCT  = 0x008,
     VMS_VARRAY  = 0x010,  /* Array with size in another field */
+    VMS_BUFFER  = 0x020,  /* static sized buffer */
 };
 
 typedef struct {
@@ -321,6 +322,7 @@
 extern const VMStateInfo vmstate_info_uint64;
 
 extern const VMStateInfo vmstate_info_timer;
+extern const VMStateInfo vmstate_info_buffer;
 
 #define type_check_array(t1,t2,n) ((t1(*)[n])0 - (t2*)0)
 #define type_check_pointer(t1,t2) ((t1**)0 - (t2*)0)
@@ -389,6 +391,16 @@
         + type_check_array(_type,typeof_field(_state, _field),_num)  \
 }
 
+#define VMSTATE_STATIC_BUFFER(_field, _state, _version) {            \
+    .name       = (stringify(_field)),                               \
+    .version_id = (_version),                                        \
+    .size       = sizeof(typeof_field(_state,_field)),               \
+    .info       = &vmstate_info_buffer,                              \
+    .flags      = VMS_BUFFER,                                        \
+    .offset     = offsetof(_state, _field)                           \
+        + type_check_array(uint8_t,typeof_field(_state, _field),sizeof(typeof_field(_state,_field))) \
+}
+
 /* _f : field name
    _f_n : num of elements field_name
    _n : num of elements
@@ -459,6 +471,12 @@
 #define VMSTATE_INT32_VARRAY(_f, _s, _f_n)                            \
     VMSTATE_INT32_VARRAY_V(_f, _s, _f_n, 0)
 
+#define VMSTATE_BUFFER_V(_f, _s, _v)                                  \
+    VMSTATE_STATIC_BUFFER(_f, _s, _v)
+
+#define VMSTATE_BUFFER(_f, _s)                                        \
+    VMSTATE_STATIC_BUFFER(_f, _s, 0)
+
 #define VMSTATE_END_OF_LIST()                                         \
     {}
 
diff --git a/savevm.c b/savevm.c
index 0290c2e..68fe924 100644
--- a/savevm.c
+++ b/savevm.c
@@ -848,6 +848,27 @@
     .put  = put_timer,
 };
 
+/* uint8_t buffers */
+
+static int get_buffer(QEMUFile *f, void *pv, size_t size)
+{
+    uint8_t *v = pv;
+    qemu_get_buffer(f, v, size);
+    return 0;
+}
+
+static void put_buffer(QEMUFile *f, const void *pv, size_t size)
+{
+    uint8_t *v = (void *)pv;
+    qemu_put_buffer(f, v, size);
+}
+
+const VMStateInfo vmstate_info_buffer = {
+    .name = "buffer",
+    .get  = get_buffer,
+    .put  = put_buffer,
+};
+
 typedef struct SaveStateEntry {
     char idstr[256];
     int instance_id;