blob: 5d69e8a00b4873b416868d271b45f4e6a39af42e [file] [log] [blame]
Paolo Bonzini28c28972010-04-01 19:57:12 +02001/*
Amit Shah73428a82011-07-20 13:35:30 +05302 * Generic Balloon handlers and management
Paolo Bonzini28c28972010-04-01 19:57:12 +02003 *
4 * Copyright (c) 2003-2008 Fabrice Bellard
Amit Shah73428a82011-07-20 13:35:30 +05305 * Copyright (C) 2011 Red Hat, Inc.
6 * Copyright (C) 2011 Amit Shah <amit.shah@redhat.com>
Paolo Bonzini28c28972010-04-01 19:57:12 +02007 *
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:
14 *
15 * The above copyright notice and this permission notice shall be included in
16 * all copies or substantial portions of the Software.
17 *
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
24 * THE SOFTWARE.
25 */
26
Markus Armbrustera0b1a662015-03-17 18:16:21 +010027#include "qemu-common.h"
Paolo Bonzini022c62c2012-12-17 18:19:49 +010028#include "exec/cpu-common.h"
Paolo Bonzini9c17d612012-12-17 18:20:04 +010029#include "sysemu/kvm.h"
30#include "sysemu/balloon.h"
Prerna Saxena62dd89d2010-08-11 17:16:03 +053031#include "trace.h"
Luiz Capitulino96637bc2011-10-21 11:41:37 -020032#include "qmp-commands.h"
Markus Armbrustercc7a8ea2015-03-17 17:22:46 +010033#include "qapi/qmp/qerror.h"
Paolo Bonzini7b1b5d12012-12-17 18:19:43 +010034#include "qapi/qmp/qjson.h"
Paolo Bonzini28c28972010-04-01 19:57:12 +020035
Amit Shah0a2a30d2011-07-20 13:08:46 +053036static QEMUBalloonEvent *balloon_event_fn;
Amit Shah30fb2ca2011-07-20 13:30:56 +053037static QEMUBalloonStatus *balloon_stat_fn;
Amit Shah0a2a30d2011-07-20 13:08:46 +053038static void *balloon_opaque;
Paolo Bonzini28c28972010-04-01 19:57:12 +020039
Eric Blake438e8282015-02-10 15:40:30 -070040static bool have_balloon(Error **errp)
Markus Armbruster422e0502015-01-13 17:44:14 +010041{
42 if (kvm_enabled() && !kvm_has_sync_mmu()) {
Markus Armbruster2ad28a02015-01-13 17:50:23 +010043 error_set(errp, ERROR_CLASS_KVM_MISSING_CAP,
44 "Using KVM without synchronous MMU, balloon unavailable");
Markus Armbruster422e0502015-01-13 17:44:14 +010045 return false;
46 }
47 if (!balloon_event_fn) {
Markus Armbruster2ad28a02015-01-13 17:50:23 +010048 error_set(errp, ERROR_CLASS_DEVICE_NOT_ACTIVE,
49 "No balloon device has been activated");
Markus Armbruster422e0502015-01-13 17:44:14 +010050 return false;
51 }
52 return true;
53}
54
Amit Shah6c6ec182011-07-27 12:28:19 +053055int qemu_add_balloon_handler(QEMUBalloonEvent *event_func,
56 QEMUBalloonStatus *stat_func, void *opaque)
Paolo Bonzini28c28972010-04-01 19:57:12 +020057{
Amit Shah6c6ec182011-07-27 12:28:19 +053058 if (balloon_event_fn || balloon_stat_fn || balloon_opaque) {
59 /* We're already registered one balloon handler. How many can
60 * a guest really have?
61 */
Amit Shah6c6ec182011-07-27 12:28:19 +053062 return -1;
63 }
Amit Shah30fb2ca2011-07-20 13:30:56 +053064 balloon_event_fn = event_func;
65 balloon_stat_fn = stat_func;
Amit Shah0a2a30d2011-07-20 13:08:46 +053066 balloon_opaque = opaque;
Amit Shah6c6ec182011-07-27 12:28:19 +053067 return 0;
Paolo Bonzini28c28972010-04-01 19:57:12 +020068}
69
Amit Shah8a7d5522011-09-09 14:30:39 +053070void qemu_remove_balloon_handler(void *opaque)
71{
72 if (balloon_opaque != opaque) {
73 return;
74 }
75 balloon_event_fn = NULL;
76 balloon_stat_fn = NULL;
77 balloon_opaque = NULL;
78}
79
Luiz Capitulino96637bc2011-10-21 11:41:37 -020080BalloonInfo *qmp_query_balloon(Error **errp)
Paolo Bonzini28c28972010-04-01 19:57:12 +020081{
Luiz Capitulino96637bc2011-10-21 11:41:37 -020082 BalloonInfo *info;
Paolo Bonzini28c28972010-04-01 19:57:12 +020083
Eric Blake438e8282015-02-10 15:40:30 -070084 if (!have_balloon(errp)) {
Luiz Capitulino96637bc2011-10-21 11:41:37 -020085 return NULL;
Paolo Bonzini28c28972010-04-01 19:57:12 +020086 }
87
Markus Armbruster6502a142015-01-13 17:43:25 +010088 info = g_malloc0(sizeof(*info));
89 balloon_stat_fn(balloon_opaque, info);
Luiz Capitulino96637bc2011-10-21 11:41:37 -020090 return info;
Paolo Bonzini28c28972010-04-01 19:57:12 +020091}
92
Markus Armbruster6502a142015-01-13 17:43:25 +010093void qmp_balloon(int64_t target, Error **errp)
Paolo Bonzini28c28972010-04-01 19:57:12 +020094{
Eric Blake438e8282015-02-10 15:40:30 -070095 if (!have_balloon(errp)) {
Luiz Capitulinod72f3262011-11-25 14:38:09 -020096 return;
Paolo Bonzini28c28972010-04-01 19:57:12 +020097 }
98
Markus Armbruster6502a142015-01-13 17:43:25 +010099 if (target <= 0) {
Markus Armbrusterc6bd8c72015-03-17 11:54:50 +0100100 error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "target", "a size");
Luiz Capitulinod72f3262011-11-25 14:38:09 -0200101 return;
Amit Shah514e73e2011-07-27 16:50:54 +0530102 }
Markus Armbruster6502a142015-01-13 17:43:25 +0100103
104 trace_balloon_event(balloon_opaque, target);
105 balloon_event_fn(balloon_opaque, target);
Paolo Bonzini28c28972010-04-01 19:57:12 +0200106}