balloon: Factor out common "is balloon active" test
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
diff --git a/balloon.c b/balloon.c
index 2884c2d..728bb70 100644
--- a/balloon.c
+++ b/balloon.c
@@ -36,6 +36,19 @@
static QEMUBalloonStatus *balloon_stat_fn;
static void *balloon_opaque;
+static bool have_ballon(Error **errp)
+{
+ if (kvm_enabled() && !kvm_has_sync_mmu()) {
+ error_set(errp, QERR_KVM_MISSING_CAP, "synchronous MMU", "balloon");
+ return false;
+ }
+ if (!balloon_event_fn) {
+ error_set(errp, QERR_DEVICE_NOT_ACTIVE, "balloon");
+ return false;
+ }
+ return true;
+}
+
int qemu_add_balloon_handler(QEMUBalloonEvent *event_func,
QEMUBalloonStatus *stat_func, void *opaque)
{
@@ -66,13 +79,7 @@
{
BalloonInfo *info;
- if (kvm_enabled() && !kvm_has_sync_mmu()) {
- error_set(errp, QERR_KVM_MISSING_CAP, "synchronous MMU", "balloon");
- return NULL;
- }
-
- if (!balloon_stat_fn) {
- error_set(errp, QERR_DEVICE_NOT_ACTIVE, "balloon");
+ if (!have_ballon(errp)) {
return NULL;
}
@@ -83,8 +90,7 @@
void qmp_balloon(int64_t target, Error **errp)
{
- if (kvm_enabled() && !kvm_has_sync_mmu()) {
- error_set(errp, QERR_KVM_MISSING_CAP, "synchronous MMU", "balloon");
+ if (!have_ballon(errp)) {
return;
}
@@ -92,11 +98,6 @@
error_set(errp, QERR_INVALID_PARAMETER_VALUE, "target", "a size");
return;
}
-
- if (!balloon_event_fn) {
- error_set(errp, QERR_DEVICE_NOT_ACTIVE, "balloon");
- return;
- }
trace_balloon_event(balloon_opaque, target);
balloon_event_fn(balloon_opaque, target);