/* * Generic Balloon handlers and management * * Copyright (c) 2003-2008 Fabrice Bellard * Copyright (C) 2011 Red Hat, Inc. * Copyright (C) 2011 Amit Shah <amit.shah@redhat.com> * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ #include "monitor.h" #include "qjson.h" #include "qint.h" #include "cpu-common.h" #include "kvm.h" #include "balloon.h" #include "trace.h" static QEMUBalloonEvent *balloon_event_fn; static QEMUBalloonStatus *balloon_stat_fn; static void *balloon_opaque; int qemu_add_balloon_handler(QEMUBalloonEvent *event_func, QEMUBalloonStatus *stat_func, void *opaque) { if (balloon_event_fn || balloon_stat_fn || balloon_opaque) { /* We're already registered one balloon handler. How many can * a guest really have? */ error_report("Another balloon device already registered"); return -1; } balloon_event_fn = event_func; balloon_stat_fn = stat_func; balloon_opaque = opaque; return 0; } static int qemu_balloon(ram_addr_t target) { if (!balloon_event_fn) { return 0; } trace_balloon_event(balloon_opaque, target); balloon_event_fn(balloon_opaque, target); return 1; } static int qemu_balloon_status(MonitorCompletion cb, void *opaque) { if (!balloon_stat_fn) { return 0; } balloon_stat_fn(balloon_opaque, cb, opaque); return 1; } static void print_balloon_stat(const char *key, QObject *obj, void *opaque) { Monitor *mon = opaque; if (strcmp(key, "actual")) { monitor_printf(mon, ",%s=%" PRId64, key, qint_get_int(qobject_to_qint(obj))); } } void monitor_print_balloon(Monitor *mon, const QObject *data) { QDict *qdict; qdict = qobject_to_qdict(data); if (!qdict_haskey(qdict, "actual")) { return; } monitor_printf(mon, "balloon: actual=%" PRId64, qdict_get_int(qdict, "actual") >> 20); qdict_iter(qdict, print_balloon_stat, mon); monitor_printf(mon, "\n"); } /** * do_info_balloon(): Balloon information * * Make an asynchronous request for balloon info. When the request completes * a QDict will be returned according to the following specification: * * - "actual": current balloon value in bytes * The following fields may or may not be present: * - "mem_swapped_in": Amount of memory swapped in (bytes) * - "mem_swapped_out": Amount of memory swapped out (bytes) * - "major_page_faults": Number of major faults * - "minor_page_faults": Number of minor faults * - "free_mem": Total amount of free and unused memory (bytes) * - "total_mem": Total amount of available memory (bytes) * * Example: * * { "actual": 1073741824, "mem_swapped_in": 0, "mem_swapped_out": 0, * "major_page_faults": 142, "minor_page_faults": 239245, * "free_mem": 1014185984, "total_mem": 1044668416 } */ int do_info_balloon(Monitor *mon, MonitorCompletion cb, void *opaque) { int ret; if (kvm_enabled() && !kvm_has_sync_mmu()) { qerror_report(QERR_KVM_MISSING_CAP, "synchronous MMU", "balloon"); return -1; } ret = qemu_balloon_status(cb, opaque); if (!ret) { qerror_report(QERR_DEVICE_NOT_ACTIVE, "balloon"); return -1; } return 0; } /** * do_balloon(): Request VM to change its memory allocation */ int do_balloon(Monitor *mon, const QDict *params, MonitorCompletion cb, void *opaque) { int64_t target; int ret; if (kvm_enabled() && !kvm_has_sync_mmu()) { qerror_report(QERR_KVM_MISSING_CAP, "synchronous MMU", "balloon"); return -1; } target = qdict_get_int(params, "value"); if (target <= 0) { qerror_report(QERR_INVALID_PARAMETER_VALUE, "target", "a size"); return -1; } ret = qemu_balloon(target); if (ret == 0) { qerror_report(QERR_DEVICE_NOT_ACTIVE, "balloon"); return -1; } cb(opaque, NULL); return 0; }