lguest: write more information to userspace about pending traps.
This is preparation for userspace handling MMIO and ioport accesses.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/drivers/lguest/lguest_user.c b/drivers/lguest/lguest_user.c
index 7f14c15..dcf9efd 100644
--- a/drivers/lguest/lguest_user.c
+++ b/drivers/lguest/lguest_user.c
@@ -29,6 +29,10 @@
unsigned int i;
struct lg_eventfd_map *map;
+ /* We only connect LHCALL_NOTIFY to event fds, not other traps. */
+ if (cpu->pending.trap != LGUEST_TRAP_ENTRY)
+ return false;
+
/*
* This "rcu_read_lock()" helps track when someone is still looking at
* the (RCU-using) eventfds array. It's not actually a lock at all;
@@ -52,9 +56,9 @@
* we'll continue to use the old array and just won't see the new one.
*/
for (i = 0; i < map->num; i++) {
- if (map->map[i].addr == cpu->pending_notify) {
+ if (map->map[i].addr == cpu->pending.addr) {
eventfd_signal(map->map[i].event, 1);
- cpu->pending_notify = 0;
+ cpu->pending.trap = 0;
break;
}
}
@@ -62,7 +66,7 @@
rcu_read_unlock();
/* If we cleared the notification, it's because we found a match. */
- return cpu->pending_notify == 0;
+ return cpu->pending.trap == 0;
}
/*L:055
@@ -282,8 +286,8 @@
* If we returned from read() last time because the Guest sent I/O,
* clear the flag.
*/
- if (cpu->pending_notify)
- cpu->pending_notify = 0;
+ if (cpu->pending.trap)
+ cpu->pending.trap = 0;
/* Run the Guest until something interesting happens. */
return run_guest(cpu, (unsigned long __user *)user);