cachepc-qemu

Fork of AMDESE/qemu with changes for cachepc side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-qemu
Log | Files | Refs | Submodules | LICENSE | sfeed.txt

balloon.c (3230B)

      1/*
      2 * Generic Balloon handlers and management
      3 *
      4 * Copyright (c) 2003-2008 Fabrice Bellard
      5 * Copyright (C) 2011 Red Hat, Inc.
      6 * Copyright (C) 2011 Amit Shah <amit.shah@redhat.com>
      7 *
      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
     27#include "qemu/osdep.h"
     28#include "qemu/atomic.h"
     29#include "sysemu/kvm.h"
     30#include "sysemu/balloon.h"
     31#include "qapi/error.h"
     32#include "qapi/qapi-commands-machine.h"
     33#include "qapi/qmp/qerror.h"
     34#include "trace.h"
     35
     36static QEMUBalloonEvent *balloon_event_fn;
     37static QEMUBalloonStatus *balloon_stat_fn;
     38static void *balloon_opaque;
     39
     40static bool have_balloon(Error **errp)
     41{
     42    if (kvm_enabled() && !kvm_has_sync_mmu()) {
     43        error_set(errp, ERROR_CLASS_KVM_MISSING_CAP,
     44                  "Using KVM without synchronous MMU, balloon unavailable");
     45        return false;
     46    }
     47    if (!balloon_event_fn) {
     48        error_set(errp, ERROR_CLASS_DEVICE_NOT_ACTIVE,
     49                  "No balloon device has been activated");
     50        return false;
     51    }
     52    return true;
     53}
     54
     55int qemu_add_balloon_handler(QEMUBalloonEvent *event_func,
     56                             QEMUBalloonStatus *stat_func, void *opaque)
     57{
     58    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         */
     62        return -1;
     63    }
     64    balloon_event_fn = event_func;
     65    balloon_stat_fn = stat_func;
     66    balloon_opaque = opaque;
     67    return 0;
     68}
     69
     70void 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
     80BalloonInfo *qmp_query_balloon(Error **errp)
     81{
     82    BalloonInfo *info;
     83
     84    if (!have_balloon(errp)) {
     85        return NULL;
     86    }
     87
     88    info = g_malloc0(sizeof(*info));
     89    balloon_stat_fn(balloon_opaque, info);
     90    return info;
     91}
     92
     93void qmp_balloon(int64_t target, Error **errp)
     94{
     95    if (!have_balloon(errp)) {
     96        return;
     97    }
     98
     99    if (target <= 0) {
    100        error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "target", "a size");
    101        return;
    102    }
    103
    104    trace_balloon_event(balloon_opaque, target);
    105    balloon_event_fn(balloon_opaque, target);
    106}