meson: convert hw/vfio
[qemu.git] / hw / block / vhost-user-blk.c
1 /*
2 * vhost-user-blk host device
3 *
4 * Copyright(C) 2017 Intel Corporation.
5 *
6 * Authors:
7 * Changpeng Liu <changpeng.liu@intel.com>
8 *
9 * Largely based on the "vhost-user-scsi.c" and "vhost-scsi.c" implemented by:
10 * Felipe Franciosi <felipe@nutanix.com>
11 * Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
12 * Nicholas Bellinger <nab@risingtidesystems.com>
13 *
14 * This work is licensed under the terms of the GNU LGPL, version 2 or later.
15 * See the COPYING.LIB file in the top-level directory.
16 *
17 */
18
19 #include "qemu/osdep.h"
20 #include "qapi/error.h"
21 #include "qemu/error-report.h"
22 #include "qemu/cutils.h"
23 #include "hw/qdev-core.h"
24 #include "hw/qdev-properties.h"
25 #include "hw/virtio/vhost.h"
26 #include "hw/virtio/vhost-user-blk.h"
27 #include "hw/virtio/virtio.h"
28 #include "hw/virtio/virtio-bus.h"
29 #include "hw/virtio/virtio-access.h"
30 #include "sysemu/sysemu.h"
31 #include "sysemu/runstate.h"
32
33 static const int user_feature_bits[] = {
34 VIRTIO_BLK_F_SIZE_MAX,
35 VIRTIO_BLK_F_SEG_MAX,
36 VIRTIO_BLK_F_GEOMETRY,
37 VIRTIO_BLK_F_BLK_SIZE,
38 VIRTIO_BLK_F_TOPOLOGY,
39 VIRTIO_BLK_F_MQ,
40 VIRTIO_BLK_F_RO,
41 VIRTIO_BLK_F_FLUSH,
42 VIRTIO_BLK_F_CONFIG_WCE,
43 VIRTIO_BLK_F_DISCARD,
44 VIRTIO_BLK_F_WRITE_ZEROES,
45 VIRTIO_F_VERSION_1,
46 VIRTIO_RING_F_INDIRECT_DESC,
47 VIRTIO_RING_F_EVENT_IDX,
48 VIRTIO_F_NOTIFY_ON_EMPTY,
49 VHOST_INVALID_FEATURE_BIT
50 };
51
52 static void vhost_user_blk_update_config(VirtIODevice *vdev, uint8_t *config)
53 {
54 VHostUserBlk *s = VHOST_USER_BLK(vdev);
55
56 memcpy(config, &s->blkcfg, sizeof(struct virtio_blk_config));
57 }
58
59 static void vhost_user_blk_set_config(VirtIODevice *vdev, const uint8_t *config)
60 {
61 VHostUserBlk *s = VHOST_USER_BLK(vdev);
62 struct virtio_blk_config *blkcfg = (struct virtio_blk_config *)config;
63 int ret;
64
65 if (blkcfg->wce == s->blkcfg.wce) {
66 return;
67 }
68
69 ret = vhost_dev_set_config(&s->dev, &blkcfg->wce,
70 offsetof(struct virtio_blk_config, wce),
71 sizeof(blkcfg->wce),
72 VHOST_SET_CONFIG_TYPE_MASTER);
73 if (ret) {
74 error_report("set device config space failed");
75 return;
76 }
77
78 s->blkcfg.wce = blkcfg->wce;
79 }
80
81 static int vhost_user_blk_handle_config_change(struct vhost_dev *dev)
82 {
83 int ret;
84 struct virtio_blk_config blkcfg;
85 VHostUserBlk *s = VHOST_USER_BLK(dev->vdev);
86
87 ret = vhost_dev_get_config(dev, (uint8_t *)&blkcfg,
88 sizeof(struct virtio_blk_config));
89 if (ret < 0) {
90 error_report("get config space failed");
91 return -1;
92 }
93
94 /* valid for resize only */
95 if (blkcfg.capacity != s->blkcfg.capacity) {
96 s->blkcfg.capacity = blkcfg.capacity;
97 memcpy(dev->vdev->config, &s->blkcfg, sizeof(struct virtio_blk_config));
98 virtio_notify_config(dev->vdev);
99 }
100
101 return 0;
102 }
103
104 const VhostDevConfigOps blk_ops = {
105 .vhost_dev_config_notifier = vhost_user_blk_handle_config_change,
106 };
107
108 static int vhost_user_blk_start(VirtIODevice *vdev)
109 {
110 VHostUserBlk *s = VHOST_USER_BLK(vdev);
111 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
112 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
113 int i, ret;
114
115 if (!k->set_guest_notifiers) {
116 error_report("binding does not support guest notifiers");
117 return -ENOSYS;
118 }
119
120 ret = vhost_dev_enable_notifiers(&s->dev, vdev);
121 if (ret < 0) {
122 error_report("Error enabling host notifiers: %d", -ret);
123 return ret;
124 }
125
126 ret = k->set_guest_notifiers(qbus->parent, s->dev.nvqs, true);
127 if (ret < 0) {
128 error_report("Error binding guest notifier: %d", -ret);
129 goto err_host_notifiers;
130 }
131
132 s->dev.acked_features = vdev->guest_features;
133
134 if (!s->inflight->addr) {
135 ret = vhost_dev_get_inflight(&s->dev, s->queue_size, s->inflight);
136 if (ret < 0) {
137 error_report("Error get inflight: %d", -ret);
138 goto err_guest_notifiers;
139 }
140 }
141
142 ret = vhost_dev_set_inflight(&s->dev, s->inflight);
143 if (ret < 0) {
144 error_report("Error set inflight: %d", -ret);
145 goto err_guest_notifiers;
146 }
147
148 ret = vhost_dev_start(&s->dev, vdev);
149 if (ret < 0) {
150 error_report("Error starting vhost: %d", -ret);
151 goto err_guest_notifiers;
152 }
153
154 /* guest_notifier_mask/pending not used yet, so just unmask
155 * everything here. virtio-pci will do the right thing by
156 * enabling/disabling irqfd.
157 */
158 for (i = 0; i < s->dev.nvqs; i++) {
159 vhost_virtqueue_mask(&s->dev, vdev, i, false);
160 }
161
162 return ret;
163
164 err_guest_notifiers:
165 k->set_guest_notifiers(qbus->parent, s->dev.nvqs, false);
166 err_host_notifiers:
167 vhost_dev_disable_notifiers(&s->dev, vdev);
168 return ret;
169 }
170
171 static void vhost_user_blk_stop(VirtIODevice *vdev)
172 {
173 VHostUserBlk *s = VHOST_USER_BLK(vdev);
174 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
175 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
176 int ret;
177
178 if (!k->set_guest_notifiers) {
179 return;
180 }
181
182 vhost_dev_stop(&s->dev, vdev);
183
184 ret = k->set_guest_notifiers(qbus->parent, s->dev.nvqs, false);
185 if (ret < 0) {
186 error_report("vhost guest notifier cleanup failed: %d", ret);
187 return;
188 }
189
190 vhost_dev_disable_notifiers(&s->dev, vdev);
191 }
192
193 static void vhost_user_blk_set_status(VirtIODevice *vdev, uint8_t status)
194 {
195 VHostUserBlk *s = VHOST_USER_BLK(vdev);
196 bool should_start = virtio_device_started(vdev, status);
197 int ret;
198
199 if (!vdev->vm_running) {
200 should_start = false;
201 }
202
203 if (!s->connected) {
204 return;
205 }
206
207 if (s->dev.started == should_start) {
208 return;
209 }
210
211 if (should_start) {
212 ret = vhost_user_blk_start(vdev);
213 if (ret < 0) {
214 error_report("vhost-user-blk: vhost start failed: %s",
215 strerror(-ret));
216 qemu_chr_fe_disconnect(&s->chardev);
217 }
218 } else {
219 vhost_user_blk_stop(vdev);
220 }
221
222 }
223
224 static uint64_t vhost_user_blk_get_features(VirtIODevice *vdev,
225 uint64_t features,
226 Error **errp)
227 {
228 VHostUserBlk *s = VHOST_USER_BLK(vdev);
229
230 /* Turn on pre-defined features */
231 virtio_add_feature(&features, VIRTIO_BLK_F_SEG_MAX);
232 virtio_add_feature(&features, VIRTIO_BLK_F_GEOMETRY);
233 virtio_add_feature(&features, VIRTIO_BLK_F_TOPOLOGY);
234 virtio_add_feature(&features, VIRTIO_BLK_F_BLK_SIZE);
235 virtio_add_feature(&features, VIRTIO_BLK_F_FLUSH);
236 virtio_add_feature(&features, VIRTIO_BLK_F_RO);
237 virtio_add_feature(&features, VIRTIO_BLK_F_DISCARD);
238 virtio_add_feature(&features, VIRTIO_BLK_F_WRITE_ZEROES);
239
240 if (s->config_wce) {
241 virtio_add_feature(&features, VIRTIO_BLK_F_CONFIG_WCE);
242 }
243 if (s->num_queues > 1) {
244 virtio_add_feature(&features, VIRTIO_BLK_F_MQ);
245 }
246
247 return vhost_get_features(&s->dev, user_feature_bits, features);
248 }
249
250 static void vhost_user_blk_handle_output(VirtIODevice *vdev, VirtQueue *vq)
251 {
252 VHostUserBlk *s = VHOST_USER_BLK(vdev);
253 int i, ret;
254
255 if (!vdev->start_on_kick) {
256 return;
257 }
258
259 if (!s->connected) {
260 return;
261 }
262
263 if (s->dev.started) {
264 return;
265 }
266
267 /* Some guests kick before setting VIRTIO_CONFIG_S_DRIVER_OK so start
268 * vhost here instead of waiting for .set_status().
269 */
270 ret = vhost_user_blk_start(vdev);
271 if (ret < 0) {
272 error_report("vhost-user-blk: vhost start failed: %s",
273 strerror(-ret));
274 qemu_chr_fe_disconnect(&s->chardev);
275 return;
276 }
277
278 /* Kick right away to begin processing requests already in vring */
279 for (i = 0; i < s->dev.nvqs; i++) {
280 VirtQueue *kick_vq = virtio_get_queue(vdev, i);
281
282 if (!virtio_queue_get_desc_addr(vdev, i)) {
283 continue;
284 }
285 event_notifier_set(virtio_queue_get_host_notifier(kick_vq));
286 }
287 }
288
289 static void vhost_user_blk_reset(VirtIODevice *vdev)
290 {
291 VHostUserBlk *s = VHOST_USER_BLK(vdev);
292
293 vhost_dev_free_inflight(s->inflight);
294 }
295
296 static int vhost_user_blk_connect(DeviceState *dev)
297 {
298 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
299 VHostUserBlk *s = VHOST_USER_BLK(vdev);
300 int ret = 0;
301
302 if (s->connected) {
303 return 0;
304 }
305 s->connected = true;
306
307 s->dev.nvqs = s->num_queues;
308 s->dev.vqs = s->vhost_vqs;
309 s->dev.vq_index = 0;
310 s->dev.backend_features = 0;
311
312 vhost_dev_set_config_notifier(&s->dev, &blk_ops);
313
314 ret = vhost_dev_init(&s->dev, &s->vhost_user, VHOST_BACKEND_TYPE_USER, 0);
315 if (ret < 0) {
316 error_report("vhost-user-blk: vhost initialization failed: %s",
317 strerror(-ret));
318 return ret;
319 }
320
321 /* restore vhost state */
322 if (virtio_device_started(vdev, vdev->status)) {
323 ret = vhost_user_blk_start(vdev);
324 if (ret < 0) {
325 error_report("vhost-user-blk: vhost start failed: %s",
326 strerror(-ret));
327 return ret;
328 }
329 }
330
331 return 0;
332 }
333
334 static void vhost_user_blk_disconnect(DeviceState *dev)
335 {
336 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
337 VHostUserBlk *s = VHOST_USER_BLK(vdev);
338
339 if (!s->connected) {
340 return;
341 }
342 s->connected = false;
343
344 if (s->dev.started) {
345 vhost_user_blk_stop(vdev);
346 }
347
348 vhost_dev_cleanup(&s->dev);
349 }
350
351 static void vhost_user_blk_event(void *opaque, QEMUChrEvent event);
352
353 static void vhost_user_blk_chr_closed_bh(void *opaque)
354 {
355 DeviceState *dev = opaque;
356 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
357 VHostUserBlk *s = VHOST_USER_BLK(vdev);
358
359 vhost_user_blk_disconnect(dev);
360 qemu_chr_fe_set_handlers(&s->chardev, NULL, NULL, vhost_user_blk_event,
361 NULL, opaque, NULL, true);
362 }
363
364 static void vhost_user_blk_event(void *opaque, QEMUChrEvent event)
365 {
366 DeviceState *dev = opaque;
367 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
368 VHostUserBlk *s = VHOST_USER_BLK(vdev);
369
370 switch (event) {
371 case CHR_EVENT_OPENED:
372 if (vhost_user_blk_connect(dev) < 0) {
373 qemu_chr_fe_disconnect(&s->chardev);
374 return;
375 }
376 break;
377 case CHR_EVENT_CLOSED:
378 /*
379 * A close event may happen during a read/write, but vhost
380 * code assumes the vhost_dev remains setup, so delay the
381 * stop & clear. There are two possible paths to hit this
382 * disconnect event:
383 * 1. When VM is in the RUN_STATE_PRELAUNCH state. The
384 * vhost_user_blk_device_realize() is a caller.
385 * 2. In tha main loop phase after VM start.
386 *
387 * For p2 the disconnect event will be delayed. We can't
388 * do the same for p1, because we are not running the loop
389 * at this moment. So just skip this step and perform
390 * disconnect in the caller function.
391 *
392 * TODO: maybe it is a good idea to make the same fix
393 * for other vhost-user devices.
394 */
395 if (runstate_is_running()) {
396 AioContext *ctx = qemu_get_current_aio_context();
397
398 qemu_chr_fe_set_handlers(&s->chardev, NULL, NULL, NULL, NULL,
399 NULL, NULL, false);
400 aio_bh_schedule_oneshot(ctx, vhost_user_blk_chr_closed_bh, opaque);
401 }
402 break;
403 case CHR_EVENT_BREAK:
404 case CHR_EVENT_MUX_IN:
405 case CHR_EVENT_MUX_OUT:
406 /* Ignore */
407 break;
408 }
409 }
410
411 static void vhost_user_blk_device_realize(DeviceState *dev, Error **errp)
412 {
413 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
414 VHostUserBlk *s = VHOST_USER_BLK(vdev);
415 Error *err = NULL;
416 int i, ret;
417
418 if (!s->chardev.chr) {
419 error_setg(errp, "vhost-user-blk: chardev is mandatory");
420 return;
421 }
422
423 if (!s->num_queues || s->num_queues > VIRTIO_QUEUE_MAX) {
424 error_setg(errp, "vhost-user-blk: invalid number of IO queues");
425 return;
426 }
427
428 if (!s->queue_size) {
429 error_setg(errp, "vhost-user-blk: queue size must be non-zero");
430 return;
431 }
432
433 if (!vhost_user_init(&s->vhost_user, &s->chardev, errp)) {
434 return;
435 }
436
437 virtio_init(vdev, "virtio-blk", VIRTIO_ID_BLOCK,
438 sizeof(struct virtio_blk_config));
439
440 s->virtqs = g_new(VirtQueue *, s->num_queues);
441 for (i = 0; i < s->num_queues; i++) {
442 s->virtqs[i] = virtio_add_queue(vdev, s->queue_size,
443 vhost_user_blk_handle_output);
444 }
445
446 s->inflight = g_new0(struct vhost_inflight, 1);
447 s->vhost_vqs = g_new0(struct vhost_virtqueue, s->num_queues);
448 s->connected = false;
449
450 qemu_chr_fe_set_handlers(&s->chardev, NULL, NULL, vhost_user_blk_event,
451 NULL, (void *)dev, NULL, true);
452
453 reconnect:
454 if (qemu_chr_fe_wait_connected(&s->chardev, &err) < 0) {
455 error_report_err(err);
456 goto virtio_err;
457 }
458
459 /* check whether vhost_user_blk_connect() failed or not */
460 if (!s->connected) {
461 goto reconnect;
462 }
463
464 ret = vhost_dev_get_config(&s->dev, (uint8_t *)&s->blkcfg,
465 sizeof(struct virtio_blk_config));
466 if (ret < 0) {
467 error_report("vhost-user-blk: get block config failed");
468 goto reconnect;
469 }
470
471 if (s->blkcfg.num_queues != s->num_queues) {
472 s->blkcfg.num_queues = s->num_queues;
473 }
474
475 return;
476
477 virtio_err:
478 g_free(s->vhost_vqs);
479 s->vhost_vqs = NULL;
480 g_free(s->inflight);
481 s->inflight = NULL;
482 for (i = 0; i < s->num_queues; i++) {
483 virtio_delete_queue(s->virtqs[i]);
484 }
485 g_free(s->virtqs);
486 virtio_cleanup(vdev);
487 vhost_user_cleanup(&s->vhost_user);
488 }
489
490 static void vhost_user_blk_device_unrealize(DeviceState *dev)
491 {
492 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
493 VHostUserBlk *s = VHOST_USER_BLK(dev);
494 int i;
495
496 virtio_set_status(vdev, 0);
497 qemu_chr_fe_set_handlers(&s->chardev, NULL, NULL, NULL,
498 NULL, NULL, NULL, false);
499 vhost_dev_cleanup(&s->dev);
500 vhost_dev_free_inflight(s->inflight);
501 g_free(s->vhost_vqs);
502 s->vhost_vqs = NULL;
503 g_free(s->inflight);
504 s->inflight = NULL;
505
506 for (i = 0; i < s->num_queues; i++) {
507 virtio_delete_queue(s->virtqs[i]);
508 }
509 g_free(s->virtqs);
510 virtio_cleanup(vdev);
511 vhost_user_cleanup(&s->vhost_user);
512 }
513
514 static void vhost_user_blk_instance_init(Object *obj)
515 {
516 VHostUserBlk *s = VHOST_USER_BLK(obj);
517
518 device_add_bootindex_property(obj, &s->bootindex, "bootindex",
519 "/disk@0,0", DEVICE(obj));
520 }
521
522 static const VMStateDescription vmstate_vhost_user_blk = {
523 .name = "vhost-user-blk",
524 .minimum_version_id = 1,
525 .version_id = 1,
526 .fields = (VMStateField[]) {
527 VMSTATE_VIRTIO_DEVICE,
528 VMSTATE_END_OF_LIST()
529 },
530 };
531
532 static Property vhost_user_blk_properties[] = {
533 DEFINE_PROP_CHR("chardev", VHostUserBlk, chardev),
534 DEFINE_PROP_UINT16("num-queues", VHostUserBlk, num_queues, 1),
535 DEFINE_PROP_UINT32("queue-size", VHostUserBlk, queue_size, 128),
536 DEFINE_PROP_BIT("config-wce", VHostUserBlk, config_wce, 0, true),
537 DEFINE_PROP_END_OF_LIST(),
538 };
539
540 static void vhost_user_blk_class_init(ObjectClass *klass, void *data)
541 {
542 DeviceClass *dc = DEVICE_CLASS(klass);
543 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
544
545 device_class_set_props(dc, vhost_user_blk_properties);
546 dc->vmsd = &vmstate_vhost_user_blk;
547 set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
548 vdc->realize = vhost_user_blk_device_realize;
549 vdc->unrealize = vhost_user_blk_device_unrealize;
550 vdc->get_config = vhost_user_blk_update_config;
551 vdc->set_config = vhost_user_blk_set_config;
552 vdc->get_features = vhost_user_blk_get_features;
553 vdc->set_status = vhost_user_blk_set_status;
554 vdc->reset = vhost_user_blk_reset;
555 }
556
557 static const TypeInfo vhost_user_blk_info = {
558 .name = TYPE_VHOST_USER_BLK,
559 .parent = TYPE_VIRTIO_DEVICE,
560 .instance_size = sizeof(VHostUserBlk),
561 .instance_init = vhost_user_blk_instance_init,
562 .class_init = vhost_user_blk_class_init,
563 };
564
565 static void virtio_register_types(void)
566 {
567 type_register_static(&vhost_user_blk_info);
568 }
569
570 type_init(virtio_register_types)