/* Handle backend state transitions:
*
* The backend state starts in Initialising and the following transitions are
* allowed.
*
* Initialising -> InitWait -> Connected
* \
* \ ^ \ |
* \ | \ |
* \ | \ |
* \ | \ |
* \ | \ |
* \ | \ |
* V | V V
*
* Closed <-> Closing
*
* The state argument specifies the eventual state of the backend and the
* function transitions to that state via the shortest path.
*/
static void set_backend_state(struct backend_info *be,
enum xenbus_state state)
{
while (be->state != state) {
switch (be->state) {
case XenbusStateInitialising:
switch (state) {
case XenbusStateInitWait:
case XenbusStateConnected:
case XenbusStateClosing:
backend_switch_state(be, XenbusStateInitWait);
break;
case XenbusStateClosed:
backend_switch_state(be, XenbusStateClosed);
break;
default:
BUG();
}
break;
case XenbusStateClosed:
switch (state) {
case XenbusStateInitWait:
case XenbusStateConnected:
backend_switch_state(be, XenbusStateInitWait);
break;
case XenbusStateClosing:
backend_switch_state(be, XenbusStateClosing);
break;
default:
BUG();
}
break;
case XenbusStateInitWait:
switch (state) {
case XenbusStateConnected:
backend_connect(be);
backend_switch_state(be, XenbusStateConnected);
break;
case XenbusStateClosing:
case XenbusStateClosed:
backend_switch_state(be, XenbusStateClosing);
break;
default:
BUG();
}
break;
case XenbusStateConnected:
switch (state) {
case XenbusStateInitWait:
case XenbusStateClosing:
case XenbusStateClosed:
backend_disconnect(be);
backend_switch_state(be, XenbusStateClosing);
break;
default:
BUG();
}
break;
case XenbusStateClosing:
switch (state) {
case XenbusStateInitWait:
case XenbusStateConnected:
case XenbusStateClosed:
backend_switch_state(be, XenbusStateClosed);
break;
default:
BUG();
}
break;
default:
BUG();
}
}
}
/* Handle backend state transitions:
*
* The backend state starts in InitWait and the following transitions are
* allowed.
*
* InitWait -> Connected
*
* ^ \ |
* | \ |
* | \ |
* | \ |
* | \ |
* | \ |
* | V V
*
* Closed <-> Closing
*
* The state argument specifies the eventual state of the backend and the
* function transitions to that state via the shortest path.
*/
static void set_backend_state(struct backend_info *be,
enum xenbus_state state)
{
while (be->state != state) {
switch (be->state) {
case XenbusStateClosed:
switch (state) {
case XenbusStateInitWait:
case XenbusStateConnected:
pr_info("%s: prepare for reconnect\n",
be->dev->nodename);
backend_switch_state(be, XenbusStateInitWait);
break;
case XenbusStateClosing:
backend_switch_state(be, XenbusStateClosing);
break;
default:
BUG();
}
break;
case XenbusStateInitWait:
switch (state) {
case XenbusStateConnected:
backend_connect(be);
backend_switch_state(be, XenbusStateConnected);
break;
case XenbusStateClosing:
case XenbusStateClosed:
backend_switch_state(be, XenbusStateClosing);
break;
default:
BUG();
}
break;
case XenbusStateConnected:
switch (state) {
case XenbusStateInitWait:
case XenbusStateClosing:
case XenbusStateClosed:
backend_disconnect(be);
backend_switch_state(be, XenbusStateClosing);
break;
default:
BUG();
}
break;
case XenbusStateClosing:
switch (state) {
case XenbusStateInitWait:
case XenbusStateConnected:
case XenbusStateClosed:
backend_switch_state(be, XenbusStateClosed);
break;
default:
BUG();
}
break;
default:
BUG();
}
}
}