| /* |
| * Virtio Balloon Device |
| * |
| * Copyright IBM, Corp. 2008 |
| * Copyright (C) 2011 Red Hat, Inc. |
| * Copyright (C) 2011 Amit Shah <amit.shah@redhat.com> |
| * |
| * Authors: |
| * Anthony Liguori <aliguori@us.ibm.com> |
| * |
| * This work is licensed under the terms of the GNU GPL, version 2. See |
| * the COPYING file in the top-level directory. |
| * |
| */ |
| |
| #include "qemu/iov.h" |
| #include "qemu/timer.h" |
| #include "qemu-common.h" |
| #include "hw/virtio/virtio.h" |
| #include "hw/i386/pc.h" |
| #include "cpu.h" |
| #include "sysemu/balloon.h" |
| #include "hw/virtio/virtio-balloon.h" |
| #include "sysemu/kvm.h" |
| #include "exec/address-spaces.h" |
| #include "qapi/visitor.h" |
| |
| #if defined(__linux__) |
| #include <sys/mman.h> |
| #endif |
| |
| #include "hw/virtio/virtio-bus.h" |
| |
| static void balloon_page(void *addr, int deflate) |
| { |
| #if defined(__linux__) |
| if (!kvm_enabled() || kvm_has_sync_mmu()) |
| qemu_madvise(addr, TARGET_PAGE_SIZE, |
| deflate ? QEMU_MADV_WILLNEED : QEMU_MADV_DONTNEED); |
| #endif |
| } |
| |
| static const char *balloon_stat_names[] = { |
| [VIRTIO_BALLOON_S_SWAP_IN] = "stat-swap-in", |
| [VIRTIO_BALLOON_S_SWAP_OUT] = "stat-swap-out", |
| [VIRTIO_BALLOON_S_MAJFLT] = "stat-major-faults", |
| [VIRTIO_BALLOON_S_MINFLT] = "stat-minor-faults", |
| [VIRTIO_BALLOON_S_MEMFREE] = "stat-free-memory", |
| [VIRTIO_BALLOON_S_MEMTOT] = "stat-total-memory", |
| [VIRTIO_BALLOON_S_NR] = NULL |
| }; |
| |
| /* |
| * reset_stats - Mark all items in the stats array as unset |
| * |
| * This function needs to be called at device initialization and before |
| * updating to a set of newly-generated stats. This will ensure that no |
| * stale values stick around in case the guest reports a subset of the supported |
| * statistics. |
| */ |
| static inline void reset_stats(VirtIOBalloon *dev) |
| { |
| int i; |
| for (i = 0; i < VIRTIO_BALLOON_S_NR; dev->stats[i++] = -1); |
| } |
| |
| static bool balloon_stats_supported(const VirtIOBalloon *s) |
| { |
| VirtIODevice *vdev = VIRTIO_DEVICE(s); |
| return vdev->guest_features & (1 << VIRTIO_BALLOON_F_STATS_VQ); |
| } |
| |
| static bool balloon_stats_enabled(const VirtIOBalloon *s) |
| { |
| return s->stats_poll_interval > 0; |
| } |
| |
| static void balloon_stats_destroy_timer(VirtIOBalloon *s) |
| { |
| if (balloon_stats_enabled(s)) { |
| timer_del(s->stats_timer); |
| timer_free(s->stats_timer); |
| s->stats_timer = NULL; |
| s->stats_poll_interval = 0; |
| } |
| } |
| |
| static void balloon_stats_change_timer(VirtIOBalloon *s, int secs) |
| { |
| timer_mod(s->stats_timer, qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) + secs * 1000); |
| } |
| |
| static void balloon_stats_poll_cb(void *opaque) |
| { |
| VirtIOBalloon *s = opaque; |
| VirtIODevice *vdev = VIRTIO_DEVICE(s); |
| |
| if (!balloon_stats_supported(s)) { |
| /* re-schedule */ |
| balloon_stats_change_timer(s, s->stats_poll_interval); |
| return; |
| } |
| |
| virtqueue_push(s->svq, &s->stats_vq_elem, s->stats_vq_offset); |
| virtio_notify(vdev, s->svq); |
| } |
| |
| static void balloon_stats_get_all(Object *obj, struct Visitor *v, |
| void *opaque, const char *name, Error **errp) |
| { |
| VirtIOBalloon *s = opaque; |
| int i; |
| |
| if (!s->stats_last_update) { |
| error_setg(errp, "guest hasn't updated any stats yet"); |
| return; |
| } |
| |
| visit_start_struct(v, NULL, "guest-stats", name, 0, errp); |
| visit_type_int(v, &s->stats_last_update, "last-update", errp); |
| |
| visit_start_struct(v, NULL, NULL, "stats", 0, errp); |
| for (i = 0; i < VIRTIO_BALLOON_S_NR; i++) { |
| visit_type_int64(v, (int64_t *) &s->stats[i], balloon_stat_names[i], |
| errp); |
| } |
| visit_end_struct(v, errp); |
| |
| visit_end_struct(v, errp); |
| } |
| |
| static void balloon_stats_get_poll_interval(Object *obj, struct Visitor *v, |
| void *opaque, const char *name, |
| Error **errp) |
| { |
| VirtIOBalloon *s = opaque; |
| visit_type_int(v, &s->stats_poll_interval, name, errp); |
| } |
| |
| static void balloon_stats_set_poll_interval(Object *obj, struct Visitor *v, |
| void *opaque, const char *name, |
| Error **errp) |
| { |
| VirtIOBalloon *s = opaque; |
| Error *local_err = NULL; |
| int64_t value; |
| |
| visit_type_int(v, &value, name, &local_err); |
| if (local_err) { |
| error_propagate(errp, local_err); |
| return; |
| } |
| |
| if (value < 0) { |
| error_setg(errp, "timer value must be greater than zero"); |
| return; |
| } |
| |
| if (value == s->stats_poll_interval) { |
| return; |
| } |
| |
| if (value == 0) { |
| /* timer=0 disables the timer */ |
| balloon_stats_destroy_timer(s); |
| return; |
| } |
| |
| if (balloon_stats_enabled(s)) { |
| /* timer interval change */ |
| s->stats_poll_interval = value; |
| balloon_stats_change_timer(s, value); |
| return; |
| } |
| |
| /* create a new timer */ |
| g_assert(s->stats_timer == NULL); |
| s->stats_timer = timer_new_ms(QEMU_CLOCK_VIRTUAL, balloon_stats_poll_cb, s); |
| s->stats_poll_interval = value; |
| balloon_stats_change_timer(s, 0); |
| } |
| |
| static void virtio_balloon_handle_output(VirtIODevice *vdev, VirtQueue *vq) |
| { |
| VirtIOBalloon *s = VIRTIO_BALLOON(vdev); |
| VirtQueueElement elem; |
| MemoryRegionSection section; |
| |
| while (virtqueue_pop(vq, &elem)) { |
| size_t offset = 0; |
| uint32_t pfn; |
| |
| while (iov_to_buf(elem.out_sg, elem.out_num, offset, &pfn, 4) == 4) { |
| ram_addr_t pa; |
| ram_addr_t addr; |
| |
| pa = (ram_addr_t)ldl_p(&pfn) << VIRTIO_BALLOON_PFN_SHIFT; |
| offset += 4; |
| |
| /* FIXME: remove get_system_memory(), but how? */ |
| section = memory_region_find(get_system_memory(), pa, 1); |
| if (!int128_nz(section.size) || !memory_region_is_ram(section.mr)) |
| continue; |
| |
| /* Using memory_region_get_ram_ptr is bending the rules a bit, but |
| should be OK because we only want a single page. */ |
| addr = section.offset_within_region; |
| balloon_page(memory_region_get_ram_ptr(section.mr) + addr, |
| !!(vq == s->dvq)); |
| memory_region_unref(section.mr); |
| } |
| |
| virtqueue_push(vq, &elem, offset); |
| virtio_notify(vdev, vq); |
| } |
| } |
| |
| static void virtio_balloon_receive_stats(VirtIODevice *vdev, VirtQueue *vq) |
| { |
| VirtIOBalloon *s = VIRTIO_BALLOON(vdev); |
| VirtQueueElement *elem = &s->stats_vq_elem; |
| VirtIOBalloonStat stat; |
| size_t offset = 0; |
| qemu_timeval tv; |
| |
| if (!virtqueue_pop(vq, elem)) { |
| goto out; |
| } |
| |
| /* Initialize the stats to get rid of any stale values. This is only |
| * needed to handle the case where a guest supports fewer stats than it |
| * used to (ie. it has booted into an old kernel). |
| */ |
| reset_stats(s); |
| |
| while (iov_to_buf(elem->out_sg, elem->out_num, offset, &stat, sizeof(stat)) |
| == sizeof(stat)) { |
| uint16_t tag = tswap16(stat.tag); |
| uint64_t val = tswap64(stat.val); |
| |
| offset += sizeof(stat); |
| if (tag < VIRTIO_BALLOON_S_NR) |
| s->stats[tag] = val; |
| } |
| s->stats_vq_offset = offset; |
| |
| if (qemu_gettimeofday(&tv) < 0) { |
| fprintf(stderr, "warning: %s: failed to get time of day\n", __func__); |
| goto out; |
| } |
| |
| s->stats_last_update = tv.tv_sec; |
| |
| out: |
| if (balloon_stats_enabled(s)) { |
| balloon_stats_change_timer(s, s->stats_poll_interval); |
| } |
| } |
| |
| static void virtio_balloon_get_config(VirtIODevice *vdev, uint8_t *config_data) |
| { |
| VirtIOBalloon *dev = VIRTIO_BALLOON(vdev); |
| struct virtio_balloon_config config; |
| |
| config.num_pages = cpu_to_le32(dev->num_pages); |
| config.actual = cpu_to_le32(dev->actual); |
| |
| memcpy(config_data, &config, sizeof(struct virtio_balloon_config)); |
| } |
| |
| static void virtio_balloon_set_config(VirtIODevice *vdev, |
| const uint8_t *config_data) |
| { |
| VirtIOBalloon *dev = VIRTIO_BALLOON(vdev); |
| struct virtio_balloon_config config; |
| uint32_t oldactual = dev->actual; |
| memcpy(&config, config_data, sizeof(struct virtio_balloon_config)); |
| dev->actual = le32_to_cpu(config.actual); |
| if (dev->actual != oldactual) { |
| qemu_balloon_changed(ram_size - |
| ((ram_addr_t) dev->actual << VIRTIO_BALLOON_PFN_SHIFT)); |
| } |
| } |
| |
| static uint32_t virtio_balloon_get_features(VirtIODevice *vdev, uint32_t f) |
| { |
| f |= (1 << VIRTIO_BALLOON_F_STATS_VQ); |
| return f; |
| } |
| |
| static void virtio_balloon_stat(void *opaque, BalloonInfo *info) |
| { |
| VirtIOBalloon *dev = opaque; |
| info->actual = ram_size - ((uint64_t) dev->actual << |
| VIRTIO_BALLOON_PFN_SHIFT); |
| } |
| |
| static void virtio_balloon_to_target(void *opaque, ram_addr_t target) |
| { |
| VirtIOBalloon *dev = VIRTIO_BALLOON(opaque); |
| VirtIODevice *vdev = VIRTIO_DEVICE(dev); |
| |
| if (target > ram_size) { |
| target = ram_size; |
| } |
| if (target) { |
| dev->num_pages = (ram_size - target) >> VIRTIO_BALLOON_PFN_SHIFT; |
| virtio_notify_config(vdev); |
| } |
| } |
| |
| static void virtio_balloon_save(QEMUFile *f, void *opaque) |
| { |
| VirtIOBalloon *s = VIRTIO_BALLOON(opaque); |
| VirtIODevice *vdev = VIRTIO_DEVICE(s); |
| |
| virtio_save(vdev, f); |
| |
| qemu_put_be32(f, s->num_pages); |
| qemu_put_be32(f, s->actual); |
| } |
| |
| static int virtio_balloon_load(QEMUFile *f, void *opaque, int version_id) |
| { |
| VirtIOBalloon *s = VIRTIO_BALLOON(opaque); |
| VirtIODevice *vdev = VIRTIO_DEVICE(s); |
| int ret; |
| |
| if (version_id != 1) |
| return -EINVAL; |
| |
| ret = virtio_load(vdev, f); |
| if (ret) { |
| return ret; |
| } |
| |
| s->num_pages = qemu_get_be32(f); |
| s->actual = qemu_get_be32(f); |
| return 0; |
| } |
| |
| static void virtio_balloon_device_realize(DeviceState *dev, Error **errp) |
| { |
| VirtIODevice *vdev = VIRTIO_DEVICE(dev); |
| VirtIOBalloon *s = VIRTIO_BALLOON(dev); |
| int ret; |
| |
| virtio_init(vdev, "virtio-balloon", VIRTIO_ID_BALLOON, |
| sizeof(struct virtio_balloon_config)); |
| |
| ret = qemu_add_balloon_handler(virtio_balloon_to_target, |
| virtio_balloon_stat, s); |
| |
| if (ret < 0) { |
| error_setg(errp, "Adding balloon handler failed"); |
| virtio_cleanup(vdev); |
| return; |
| } |
| |
| s->ivq = virtio_add_queue(vdev, 128, virtio_balloon_handle_output); |
| s->dvq = virtio_add_queue(vdev, 128, virtio_balloon_handle_output); |
| s->svq = virtio_add_queue(vdev, 128, virtio_balloon_receive_stats); |
| |
| register_savevm(dev, "virtio-balloon", -1, 1, |
| virtio_balloon_save, virtio_balloon_load, s); |
| |
| object_property_add(OBJECT(dev), "guest-stats", "guest statistics", |
| balloon_stats_get_all, NULL, NULL, s, NULL); |
| |
| object_property_add(OBJECT(dev), "guest-stats-polling-interval", "int", |
| balloon_stats_get_poll_interval, |
| balloon_stats_set_poll_interval, |
| NULL, s, NULL); |
| } |
| |
| static void virtio_balloon_device_unrealize(DeviceState *dev, Error **errp) |
| { |
| VirtIODevice *vdev = VIRTIO_DEVICE(dev); |
| VirtIOBalloon *s = VIRTIO_BALLOON(dev); |
| |
| balloon_stats_destroy_timer(s); |
| qemu_remove_balloon_handler(s); |
| unregister_savevm(dev, "virtio-balloon", s); |
| virtio_cleanup(vdev); |
| } |
| |
| static Property virtio_balloon_properties[] = { |
| DEFINE_PROP_END_OF_LIST(), |
| }; |
| |
| static void virtio_balloon_class_init(ObjectClass *klass, void *data) |
| { |
| DeviceClass *dc = DEVICE_CLASS(klass); |
| VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); |
| |
| dc->props = virtio_balloon_properties; |
| set_bit(DEVICE_CATEGORY_MISC, dc->categories); |
| vdc->realize = virtio_balloon_device_realize; |
| vdc->unrealize = virtio_balloon_device_unrealize; |
| vdc->get_config = virtio_balloon_get_config; |
| vdc->set_config = virtio_balloon_set_config; |
| vdc->get_features = virtio_balloon_get_features; |
| } |
| |
| static const TypeInfo virtio_balloon_info = { |
| .name = TYPE_VIRTIO_BALLOON, |
| .parent = TYPE_VIRTIO_DEVICE, |
| .instance_size = sizeof(VirtIOBalloon), |
| .class_init = virtio_balloon_class_init, |
| }; |
| |
| static void virtio_register_types(void) |
| { |
| type_register_static(&virtio_balloon_info); |
| } |
| |
| type_init(virtio_register_types) |