1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16#include "qemu/iov.h"
17#include "qemu/timer.h"
18#include "qemu-common.h"
19#include "hw/virtio/virtio.h"
20#include "hw/i386/pc.h"
21#include "cpu.h"
22#include "sysemu/balloon.h"
23#include "hw/virtio/virtio-balloon.h"
24#include "sysemu/kvm.h"
25#include "exec/address-spaces.h"
26#include "qapi/visitor.h"
27
28#if defined(__linux__)
29#include <sys/mman.h>
30#endif
31
32#include "hw/virtio/virtio-bus.h"
33
34static void balloon_page(void *addr, int deflate)
35{
36#if defined(__linux__)
37 if (!kvm_enabled() || kvm_has_sync_mmu())
38 qemu_madvise(addr, TARGET_PAGE_SIZE,
39 deflate ? QEMU_MADV_WILLNEED : QEMU_MADV_DONTNEED);
40#endif
41}
42
43static const char *balloon_stat_names[] = {
44 [VIRTIO_BALLOON_S_SWAP_IN] = "stat-swap-in",
45 [VIRTIO_BALLOON_S_SWAP_OUT] = "stat-swap-out",
46 [VIRTIO_BALLOON_S_MAJFLT] = "stat-major-faults",
47 [VIRTIO_BALLOON_S_MINFLT] = "stat-minor-faults",
48 [VIRTIO_BALLOON_S_MEMFREE] = "stat-free-memory",
49 [VIRTIO_BALLOON_S_MEMTOT] = "stat-total-memory",
50 [VIRTIO_BALLOON_S_NR] = NULL
51};
52
53
54
55
56
57
58
59
60
61static inline void reset_stats(VirtIOBalloon *dev)
62{
63 int i;
64 for (i = 0; i < VIRTIO_BALLOON_S_NR; dev->stats[i++] = -1);
65}
66
67static bool balloon_stats_supported(const VirtIOBalloon *s)
68{
69 VirtIODevice *vdev = VIRTIO_DEVICE(s);
70 return vdev->guest_features & (1 << VIRTIO_BALLOON_F_STATS_VQ);
71}
72
73static bool balloon_stats_enabled(const VirtIOBalloon *s)
74{
75 return s->stats_poll_interval > 0;
76}
77
78static void balloon_stats_destroy_timer(VirtIOBalloon *s)
79{
80 if (balloon_stats_enabled(s)) {
81 timer_del(s->stats_timer);
82 timer_free(s->stats_timer);
83 s->stats_timer = NULL;
84 s->stats_poll_interval = 0;
85 }
86}
87
88static void balloon_stats_change_timer(VirtIOBalloon *s, int secs)
89{
90 timer_mod(s->stats_timer, qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) + secs * 1000);
91}
92
93static void balloon_stats_poll_cb(void *opaque)
94{
95 VirtIOBalloon *s = opaque;
96 VirtIODevice *vdev = VIRTIO_DEVICE(s);
97
98 if (!balloon_stats_supported(s)) {
99
100 balloon_stats_change_timer(s, s->stats_poll_interval);
101 return;
102 }
103
104 virtqueue_push(s->svq, &s->stats_vq_elem, s->stats_vq_offset);
105 virtio_notify(vdev, s->svq);
106}
107
108static void balloon_stats_get_all(Object *obj, struct Visitor *v,
109 void *opaque, const char *name, Error **errp)
110{
111 VirtIOBalloon *s = opaque;
112 int i;
113
114 if (!s->stats_last_update) {
115 error_setg(errp, "guest hasn't updated any stats yet");
116 return;
117 }
118
119 visit_start_struct(v, NULL, "guest-stats", name, 0, errp);
120 visit_type_int(v, &s->stats_last_update, "last-update", errp);
121
122 visit_start_struct(v, NULL, NULL, "stats", 0, errp);
123 for (i = 0; i < VIRTIO_BALLOON_S_NR; i++) {
124 visit_type_int64(v, (int64_t *) &s->stats[i], balloon_stat_names[i],
125 errp);
126 }
127 visit_end_struct(v, errp);
128
129 visit_end_struct(v, errp);
130}
131
132static void balloon_stats_get_poll_interval(Object *obj, struct Visitor *v,
133 void *opaque, const char *name,
134 Error **errp)
135{
136 VirtIOBalloon *s = opaque;
137 visit_type_int(v, &s->stats_poll_interval, name, errp);
138}
139
140static void balloon_stats_set_poll_interval(Object *obj, struct Visitor *v,
141 void *opaque, const char *name,
142 Error **errp)
143{
144 VirtIOBalloon *s = opaque;
145 int64_t value;
146
147 visit_type_int(v, &value, name, errp);
148 if (error_is_set(errp)) {
149 return;
150 }
151
152 if (value < 0) {
153 error_setg(errp, "timer value must be greater than zero");
154 return;
155 }
156
157 if (value == s->stats_poll_interval) {
158 return;
159 }
160
161 if (value == 0) {
162
163 balloon_stats_destroy_timer(s);
164 return;
165 }
166
167 if (balloon_stats_enabled(s)) {
168
169 s->stats_poll_interval = value;
170 balloon_stats_change_timer(s, value);
171 return;
172 }
173
174
175 g_assert(s->stats_timer == NULL);
176 s->stats_timer = timer_new_ms(QEMU_CLOCK_VIRTUAL, balloon_stats_poll_cb, s);
177 s->stats_poll_interval = value;
178 balloon_stats_change_timer(s, 0);
179}
180
181static void virtio_balloon_handle_output(VirtIODevice *vdev, VirtQueue *vq)
182{
183 VirtIOBalloon *s = VIRTIO_BALLOON(vdev);
184 VirtQueueElement elem;
185 MemoryRegionSection section;
186
187 while (virtqueue_pop(vq, &elem)) {
188 size_t offset = 0;
189 uint32_t pfn;
190
191 while (iov_to_buf(elem.out_sg, elem.out_num, offset, &pfn, 4) == 4) {
192 ram_addr_t pa;
193 ram_addr_t addr;
194
195 pa = (ram_addr_t)ldl_p(&pfn) << VIRTIO_BALLOON_PFN_SHIFT;
196 offset += 4;
197
198
199 section = memory_region_find(get_system_memory(), pa, 1);
200 if (!int128_nz(section.size) || !memory_region_is_ram(section.mr))
201 continue;
202
203
204
205 addr = section.offset_within_region;
206 balloon_page(memory_region_get_ram_ptr(section.mr) + addr,
207 !!(vq == s->dvq));
208 memory_region_unref(section.mr);
209 }
210
211 virtqueue_push(vq, &elem, offset);
212 virtio_notify(vdev, vq);
213 }
214}
215
216static void virtio_balloon_receive_stats(VirtIODevice *vdev, VirtQueue *vq)
217{
218 VirtIOBalloon *s = VIRTIO_BALLOON(vdev);
219 VirtQueueElement *elem = &s->stats_vq_elem;
220 VirtIOBalloonStat stat;
221 size_t offset = 0;
222 qemu_timeval tv;
223
224 if (!virtqueue_pop(vq, elem)) {
225 goto out;
226 }
227
228
229
230
231
232 reset_stats(s);
233
234 while (iov_to_buf(elem->out_sg, elem->out_num, offset, &stat, sizeof(stat))
235 == sizeof(stat)) {
236 uint16_t tag = tswap16(stat.tag);
237 uint64_t val = tswap64(stat.val);
238
239 offset += sizeof(stat);
240 if (tag < VIRTIO_BALLOON_S_NR)
241 s->stats[tag] = val;
242 }
243 s->stats_vq_offset = offset;
244
245 if (qemu_gettimeofday(&tv) < 0) {
246 fprintf(stderr, "warning: %s: failed to get time of day\n", __func__);
247 goto out;
248 }
249
250 s->stats_last_update = tv.tv_sec;
251
252out:
253 if (balloon_stats_enabled(s)) {
254 balloon_stats_change_timer(s, s->stats_poll_interval);
255 }
256}
257
258static void virtio_balloon_get_config(VirtIODevice *vdev, uint8_t *config_data)
259{
260 VirtIOBalloon *dev = VIRTIO_BALLOON(vdev);
261 struct virtio_balloon_config config;
262
263 config.num_pages = cpu_to_le32(dev->num_pages);
264 config.actual = cpu_to_le32(dev->actual);
265
266 memcpy(config_data, &config, sizeof(struct virtio_balloon_config));
267}
268
269static void virtio_balloon_set_config(VirtIODevice *vdev,
270 const uint8_t *config_data)
271{
272 VirtIOBalloon *dev = VIRTIO_BALLOON(vdev);
273 struct virtio_balloon_config config;
274 uint32_t oldactual = dev->actual;
275 memcpy(&config, config_data, sizeof(struct virtio_balloon_config));
276 dev->actual = le32_to_cpu(config.actual);
277 if (dev->actual != oldactual) {
278 qemu_balloon_changed(ram_size -
279 ((ram_addr_t) dev->actual << VIRTIO_BALLOON_PFN_SHIFT));
280 }
281}
282
283static uint32_t virtio_balloon_get_features(VirtIODevice *vdev, uint32_t f)
284{
285 f |= (1 << VIRTIO_BALLOON_F_STATS_VQ);
286 return f;
287}
288
289static void virtio_balloon_stat(void *opaque, BalloonInfo *info)
290{
291 VirtIOBalloon *dev = opaque;
292 info->actual = ram_size - ((uint64_t) dev->actual <<
293 VIRTIO_BALLOON_PFN_SHIFT);
294}
295
296static void virtio_balloon_to_target(void *opaque, ram_addr_t target)
297{
298 VirtIOBalloon *dev = VIRTIO_BALLOON(opaque);
299 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
300
301 if (target > ram_size) {
302 target = ram_size;
303 }
304 if (target) {
305 dev->num_pages = (ram_size - target) >> VIRTIO_BALLOON_PFN_SHIFT;
306 virtio_notify_config(vdev);
307 }
308}
309
310static void virtio_balloon_save(QEMUFile *f, void *opaque)
311{
312 VirtIOBalloon *s = VIRTIO_BALLOON(opaque);
313 VirtIODevice *vdev = VIRTIO_DEVICE(s);
314
315 virtio_save(vdev, f);
316
317 qemu_put_be32(f, s->num_pages);
318 qemu_put_be32(f, s->actual);
319}
320
321static int virtio_balloon_load(QEMUFile *f, void *opaque, int version_id)
322{
323 VirtIOBalloon *s = VIRTIO_BALLOON(opaque);
324 VirtIODevice *vdev = VIRTIO_DEVICE(s);
325 int ret;
326
327 if (version_id != 1)
328 return -EINVAL;
329
330 ret = virtio_load(vdev, f);
331 if (ret) {
332 return ret;
333 }
334
335 s->num_pages = qemu_get_be32(f);
336 s->actual = qemu_get_be32(f);
337 return 0;
338}
339
340static void virtio_balloon_device_realize(DeviceState *dev, Error **errp)
341{
342 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
343 VirtIOBalloon *s = VIRTIO_BALLOON(dev);
344 int ret;
345
346 virtio_init(vdev, "virtio-balloon", VIRTIO_ID_BALLOON,
347 sizeof(struct virtio_balloon_config));
348
349 ret = qemu_add_balloon_handler(virtio_balloon_to_target,
350 virtio_balloon_stat, s);
351
352 if (ret < 0) {
353 error_setg(errp, "Adding balloon handler failed");
354 virtio_cleanup(vdev);
355 return;
356 }
357
358 s->ivq = virtio_add_queue(vdev, 128, virtio_balloon_handle_output);
359 s->dvq = virtio_add_queue(vdev, 128, virtio_balloon_handle_output);
360 s->svq = virtio_add_queue(vdev, 128, virtio_balloon_receive_stats);
361
362 register_savevm(dev, "virtio-balloon", -1, 1,
363 virtio_balloon_save, virtio_balloon_load, s);
364
365 object_property_add(OBJECT(dev), "guest-stats", "guest statistics",
366 balloon_stats_get_all, NULL, NULL, s, NULL);
367
368 object_property_add(OBJECT(dev), "guest-stats-polling-interval", "int",
369 balloon_stats_get_poll_interval,
370 balloon_stats_set_poll_interval,
371 NULL, s, NULL);
372}
373
374static void virtio_balloon_device_unrealize(DeviceState *dev, Error **errp)
375{
376 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
377 VirtIOBalloon *s = VIRTIO_BALLOON(dev);
378
379 balloon_stats_destroy_timer(s);
380 qemu_remove_balloon_handler(s);
381 unregister_savevm(dev, "virtio-balloon", s);
382 virtio_cleanup(vdev);
383}
384
385static Property virtio_balloon_properties[] = {
386 DEFINE_PROP_END_OF_LIST(),
387};
388
389static void virtio_balloon_class_init(ObjectClass *klass, void *data)
390{
391 DeviceClass *dc = DEVICE_CLASS(klass);
392 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
393
394 dc->props = virtio_balloon_properties;
395 set_bit(DEVICE_CATEGORY_MISC, dc->categories);
396 vdc->realize = virtio_balloon_device_realize;
397 vdc->unrealize = virtio_balloon_device_unrealize;
398 vdc->get_config = virtio_balloon_get_config;
399 vdc->set_config = virtio_balloon_set_config;
400 vdc->get_features = virtio_balloon_get_features;
401}
402
403static const TypeInfo virtio_balloon_info = {
404 .name = TYPE_VIRTIO_BALLOON,
405 .parent = TYPE_VIRTIO_DEVICE,
406 .instance_size = sizeof(VirtIOBalloon),
407 .class_init = virtio_balloon_class_init,
408};
409
410static void virtio_register_types(void)
411{
412 type_register_static(&virtio_balloon_info);
413}
414
415type_init(virtio_register_types)
416
