2 * Generic Balloon handlers and management
4 * Copyright (c) 2003-2008 Fabrice Bellard
5 * Copyright (C) 2011 Red Hat, Inc.
6 * Copyright (C) 2011 Amit Shah <amit.shah@redhat.com>
8 * Permission is hereby granted, free of charge, to any person obtaining a copy
9 * of this software and associated documentation files (the "Software"), to deal
10 * in the Software without restriction, including without limitation the rights
11 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
12 * copies of the Software, and to permit persons to whom the Software is
13 * furnished to do so, subject to the following conditions:
15 * The above copyright notice and this permission notice shall be included in
16 * all copies or substantial portions of the Software.
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
21 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
22 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
23 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
27 #include "monitor/monitor.h"
28 #include "exec/cpu-common.h"
29 #include "sysemu/kvm.h"
30 #include "sysemu/balloon.h"
32 #include "qmp-commands.h"
33 #include "qapi/qmp/qjson.h"
35 static QEMUBalloonEvent *balloon_event_fn;
36 static QEMUBalloonStatus *balloon_stat_fn;
37 static void *balloon_opaque;
39 int qemu_add_balloon_handler(QEMUBalloonEvent *event_func,
40 QEMUBalloonStatus *stat_func, void *opaque)
42 if (balloon_event_fn || balloon_stat_fn || balloon_opaque) {
43 /* We're already registered one balloon handler. How many can
44 * a guest really have?
46 error_report("Another balloon device already registered");
49 balloon_event_fn = event_func;
50 balloon_stat_fn = stat_func;
51 balloon_opaque = opaque;
55 void qemu_remove_balloon_handler(void *opaque)
57 if (balloon_opaque != opaque) {
60 balloon_event_fn = NULL;
61 balloon_stat_fn = NULL;
62 balloon_opaque = NULL;
65 BalloonInfo *qmp_query_balloon(Error **errp)
69 if (kvm_enabled() && !kvm_has_sync_mmu()) {
70 error_set(errp, QERR_KVM_MISSING_CAP, "synchronous MMU", "balloon");
74 if (!balloon_stat_fn) {
75 error_set(errp, QERR_DEVICE_NOT_ACTIVE, "balloon");
79 info = g_malloc0(sizeof(*info));
80 balloon_stat_fn(balloon_opaque, info);
84 void qmp_balloon(int64_t target, Error **errp)
86 if (kvm_enabled() && !kvm_has_sync_mmu()) {
87 error_set(errp, QERR_KVM_MISSING_CAP, "synchronous MMU", "balloon");
92 error_set(errp, QERR_INVALID_PARAMETER_VALUE, "target", "a size");
96 if (!balloon_event_fn) {
97 error_set(errp, QERR_DEVICE_NOT_ACTIVE, "balloon");
101 trace_balloon_event(balloon_opaque, target);
102 balloon_event_fn(balloon_opaque, target);