pckbd: adding new fields to vmstate

This patch adds outport to VMState to allow correct saving and restoring
the state of PC keyboard controller.

Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

hw/input/pckbd.c

@@ -131,6 +131,7 @@ typedef struct KBDState {
     uint8_t status;
     uint8_t mode;
     uint8_t outport;
+    bool outport_present;
     /* Bitmask of devices with data available.  */
     uint8_t pending;
     void *kbd;
@@ -367,18 +368,68 @@ static void kbd_reset(void *opaque)
     s->mode = KBD_MODE_KBD_INT | KBD_MODE_MOUSE_INT;
     s->status = KBD_STAT_CMD | KBD_STAT_UNLOCKED;
     s->outport = KBD_OUT_RESET | KBD_OUT_A20;
+    s->outport_present = false;
+}
+
+static uint8_t kbd_outport_default(KBDState *s)
+{
+    return KBD_OUT_RESET | KBD_OUT_A20
+           | (s->status & KBD_STAT_OBF ? KBD_OUT_OBF : 0)
+           | (s->status & KBD_STAT_MOUSE_OBF ? KBD_OUT_MOUSE_OBF : 0);
+}
+
+static int kbd_outport_post_load(void *opaque, int version_id)
+{
+    KBDState *s = opaque;
+    s->outport_present = true;
+    return 0;
+}
+
+static const VMStateDescription vmstate_kbd_outport = {
+    .name = "pckbd_outport",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .post_load = kbd_outport_post_load,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT8(outport, KBDState),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static bool kbd_outport_needed(void *opaque)
+{
+    KBDState *s = opaque;
+    return s->outport != kbd_outport_default(s);
+}
+
+static int kbd_post_load(void *opaque, int version_id)
+{
+    KBDState *s = opaque;
+    if (!s->outport_present) {
+        s->outport = kbd_outport_default(s);
+    }
+    s->outport_present = false;
+    return 0;
 }
 
 static const VMStateDescription vmstate_kbd = {
     .name = "pckbd",
     .version_id = 3,
     .minimum_version_id = 3,
+    .post_load = kbd_post_load,
     .fields = (VMStateField[]) {
         VMSTATE_UINT8(write_cmd, KBDState),
         VMSTATE_UINT8(status, KBDState),
         VMSTATE_UINT8(mode, KBDState),
         VMSTATE_UINT8(pending, KBDState),
         VMSTATE_END_OF_LIST()
+    },
+    .subsections = (VMStateSubsection[]) {
+        {
+            .vmsd = &vmstate_kbd_outport,
+            .needed = kbd_outport_needed,
+        },
+        VMSTATE_END_OF_LIST()
     }
 };