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 "qom/object.h" |
24 | #include "hw/qdev-core.h" |
25 | #include "hw/qdev-properties.h" |
26 | #include "hw/virtio/vhost.h" |
27 | #include "hw/virtio/vhost-user-blk.h" |
28 | #include "hw/virtio/virtio.h" |
29 | #include "hw/virtio/virtio-bus.h" |
30 | #include "hw/virtio/virtio-access.h" |
31 | #include "sysemu/sysemu.h" |
32 | #include "sysemu/runstate.h" |
33 | |
34 | static const int user_feature_bits[] = { |
35 | VIRTIO_BLK_F_SIZE_MAX, |
36 | VIRTIO_BLK_F_SEG_MAX, |
37 | VIRTIO_BLK_F_GEOMETRY, |
38 | VIRTIO_BLK_F_BLK_SIZE, |
39 | VIRTIO_BLK_F_TOPOLOGY, |
40 | VIRTIO_BLK_F_MQ, |
41 | VIRTIO_BLK_F_RO, |
42 | VIRTIO_BLK_F_FLUSH, |
43 | VIRTIO_BLK_F_CONFIG_WCE, |
44 | VIRTIO_BLK_F_DISCARD, |
45 | VIRTIO_BLK_F_WRITE_ZEROES, |
46 | VIRTIO_F_VERSION_1, |
47 | VIRTIO_RING_F_INDIRECT_DESC, |
48 | VIRTIO_RING_F_EVENT_IDX, |
49 | VIRTIO_F_NOTIFY_ON_EMPTY, |
50 | VHOST_INVALID_FEATURE_BIT |
51 | }; |
52 | |
53 | static void vhost_user_blk_update_config(VirtIODevice *vdev, uint8_t *config) |
54 | { |
55 | VHostUserBlk *s = VHOST_USER_BLK(vdev); |
56 | |
57 | memcpy(config, &s->blkcfg, sizeof(struct virtio_blk_config)); |
58 | } |
59 | |
60 | static void vhost_user_blk_set_config(VirtIODevice *vdev, const uint8_t *config) |
61 | { |
62 | VHostUserBlk *s = VHOST_USER_BLK(vdev); |
63 | struct virtio_blk_config *blkcfg = (struct virtio_blk_config *)config; |
64 | int ret; |
65 | |
66 | if (blkcfg->wce == s->blkcfg.wce) { |
67 | return; |
68 | } |
69 | |
70 | ret = vhost_dev_set_config(&s->dev, &blkcfg->wce, |
71 | offsetof(struct virtio_blk_config, wce), |
72 | sizeof(blkcfg->wce), |
73 | VHOST_SET_CONFIG_TYPE_MASTER); |
74 | if (ret) { |
75 | error_report("set device config space failed" ); |
76 | return; |
77 | } |
78 | |
79 | s->blkcfg.wce = blkcfg->wce; |
80 | } |
81 | |
82 | static int vhost_user_blk_handle_config_change(struct vhost_dev *dev) |
83 | { |
84 | int ret; |
85 | struct virtio_blk_config blkcfg; |
86 | VHostUserBlk *s = VHOST_USER_BLK(dev->vdev); |
87 | |
88 | ret = vhost_dev_get_config(dev, (uint8_t *)&blkcfg, |
89 | sizeof(struct virtio_blk_config)); |
90 | if (ret < 0) { |
91 | error_report("get config space failed" ); |
92 | return -1; |
93 | } |
94 | |
95 | /* valid for resize only */ |
96 | if (blkcfg.capacity != s->blkcfg.capacity) { |
97 | s->blkcfg.capacity = blkcfg.capacity; |
98 | memcpy(dev->vdev->config, &s->blkcfg, sizeof(struct virtio_blk_config)); |
99 | virtio_notify_config(dev->vdev); |
100 | } |
101 | |
102 | return 0; |
103 | } |
104 | |
105 | const VhostDevConfigOps blk_ops = { |
106 | .vhost_dev_config_notifier = vhost_user_blk_handle_config_change, |
107 | }; |
108 | |
109 | static int vhost_user_blk_start(VirtIODevice *vdev) |
110 | { |
111 | VHostUserBlk *s = VHOST_USER_BLK(vdev); |
112 | BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); |
113 | VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); |
114 | int i, ret; |
115 | |
116 | if (!k->set_guest_notifiers) { |
117 | error_report("binding does not support guest notifiers" ); |
118 | return -ENOSYS; |
119 | } |
120 | |
121 | ret = vhost_dev_enable_notifiers(&s->dev, vdev); |
122 | if (ret < 0) { |
123 | error_report("Error enabling host notifiers: %d" , -ret); |
124 | return ret; |
125 | } |
126 | |
127 | ret = k->set_guest_notifiers(qbus->parent, s->dev.nvqs, true); |
128 | if (ret < 0) { |
129 | error_report("Error binding guest notifier: %d" , -ret); |
130 | goto err_host_notifiers; |
131 | } |
132 | |
133 | s->dev.acked_features = vdev->guest_features; |
134 | |
135 | if (!s->inflight->addr) { |
136 | ret = vhost_dev_get_inflight(&s->dev, s->queue_size, s->inflight); |
137 | if (ret < 0) { |
138 | error_report("Error get inflight: %d" , -ret); |
139 | goto err_guest_notifiers; |
140 | } |
141 | } |
142 | |
143 | ret = vhost_dev_set_inflight(&s->dev, s->inflight); |
144 | if (ret < 0) { |
145 | error_report("Error set inflight: %d" , -ret); |
146 | goto err_guest_notifiers; |
147 | } |
148 | |
149 | ret = vhost_dev_start(&s->dev, vdev); |
150 | if (ret < 0) { |
151 | error_report("Error starting vhost: %d" , -ret); |
152 | goto err_guest_notifiers; |
153 | } |
154 | |
155 | /* guest_notifier_mask/pending not used yet, so just unmask |
156 | * everything here. virtio-pci will do the right thing by |
157 | * enabling/disabling irqfd. |
158 | */ |
159 | for (i = 0; i < s->dev.nvqs; i++) { |
160 | vhost_virtqueue_mask(&s->dev, vdev, i, false); |
161 | } |
162 | |
163 | return ret; |
164 | |
165 | err_guest_notifiers: |
166 | k->set_guest_notifiers(qbus->parent, s->dev.nvqs, false); |
167 | err_host_notifiers: |
168 | vhost_dev_disable_notifiers(&s->dev, vdev); |
169 | return ret; |
170 | } |
171 | |
172 | static void vhost_user_blk_stop(VirtIODevice *vdev) |
173 | { |
174 | VHostUserBlk *s = VHOST_USER_BLK(vdev); |
175 | BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev))); |
176 | VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); |
177 | int ret; |
178 | |
179 | if (!k->set_guest_notifiers) { |
180 | return; |
181 | } |
182 | |
183 | vhost_dev_stop(&s->dev, vdev); |
184 | |
185 | ret = k->set_guest_notifiers(qbus->parent, s->dev.nvqs, false); |
186 | if (ret < 0) { |
187 | error_report("vhost guest notifier cleanup failed: %d" , ret); |
188 | return; |
189 | } |
190 | |
191 | vhost_dev_disable_notifiers(&s->dev, vdev); |
192 | } |
193 | |
194 | static void vhost_user_blk_set_status(VirtIODevice *vdev, uint8_t status) |
195 | { |
196 | VHostUserBlk *s = VHOST_USER_BLK(vdev); |
197 | bool should_start = virtio_device_started(vdev, status); |
198 | int ret; |
199 | |
200 | if (!vdev->vm_running) { |
201 | should_start = false; |
202 | } |
203 | |
204 | if (!s->connected) { |
205 | return; |
206 | } |
207 | |
208 | if (s->dev.started == should_start) { |
209 | return; |
210 | } |
211 | |
212 | if (should_start) { |
213 | ret = vhost_user_blk_start(vdev); |
214 | if (ret < 0) { |
215 | error_report("vhost-user-blk: vhost start failed: %s" , |
216 | strerror(-ret)); |
217 | qemu_chr_fe_disconnect(&s->chardev); |
218 | } |
219 | } else { |
220 | vhost_user_blk_stop(vdev); |
221 | } |
222 | |
223 | } |
224 | |
225 | static uint64_t vhost_user_blk_get_features(VirtIODevice *vdev, |
226 | uint64_t features, |
227 | Error **errp) |
228 | { |
229 | VHostUserBlk *s = VHOST_USER_BLK(vdev); |
230 | |
231 | /* Turn on pre-defined features */ |
232 | virtio_add_feature(&features, VIRTIO_BLK_F_SEG_MAX); |
233 | virtio_add_feature(&features, VIRTIO_BLK_F_GEOMETRY); |
234 | virtio_add_feature(&features, VIRTIO_BLK_F_TOPOLOGY); |
235 | virtio_add_feature(&features, VIRTIO_BLK_F_BLK_SIZE); |
236 | virtio_add_feature(&features, VIRTIO_BLK_F_FLUSH); |
237 | virtio_add_feature(&features, VIRTIO_BLK_F_RO); |
238 | virtio_add_feature(&features, VIRTIO_BLK_F_DISCARD); |
239 | virtio_add_feature(&features, VIRTIO_BLK_F_WRITE_ZEROES); |
240 | |
241 | if (s->config_wce) { |
242 | virtio_add_feature(&features, VIRTIO_BLK_F_CONFIG_WCE); |
243 | } |
244 | if (s->num_queues > 1) { |
245 | virtio_add_feature(&features, VIRTIO_BLK_F_MQ); |
246 | } |
247 | |
248 | return vhost_get_features(&s->dev, user_feature_bits, features); |
249 | } |
250 | |
251 | static void vhost_user_blk_handle_output(VirtIODevice *vdev, VirtQueue *vq) |
252 | { |
253 | VHostUserBlk *s = VHOST_USER_BLK(vdev); |
254 | int i, ret; |
255 | |
256 | if (!vdev->start_on_kick) { |
257 | return; |
258 | } |
259 | |
260 | if (!s->connected) { |
261 | return; |
262 | } |
263 | |
264 | if (s->dev.started) { |
265 | return; |
266 | } |
267 | |
268 | /* Some guests kick before setting VIRTIO_CONFIG_S_DRIVER_OK so start |
269 | * vhost here instead of waiting for .set_status(). |
270 | */ |
271 | ret = vhost_user_blk_start(vdev); |
272 | if (ret < 0) { |
273 | error_report("vhost-user-blk: vhost start failed: %s" , |
274 | strerror(-ret)); |
275 | qemu_chr_fe_disconnect(&s->chardev); |
276 | return; |
277 | } |
278 | |
279 | /* Kick right away to begin processing requests already in vring */ |
280 | for (i = 0; i < s->dev.nvqs; i++) { |
281 | VirtQueue *kick_vq = virtio_get_queue(vdev, i); |
282 | |
283 | if (!virtio_queue_get_desc_addr(vdev, i)) { |
284 | continue; |
285 | } |
286 | event_notifier_set(virtio_queue_get_host_notifier(kick_vq)); |
287 | } |
288 | } |
289 | |
290 | static void vhost_user_blk_reset(VirtIODevice *vdev) |
291 | { |
292 | VHostUserBlk *s = VHOST_USER_BLK(vdev); |
293 | |
294 | vhost_dev_free_inflight(s->inflight); |
295 | } |
296 | |
297 | static int vhost_user_blk_connect(DeviceState *dev) |
298 | { |
299 | VirtIODevice *vdev = VIRTIO_DEVICE(dev); |
300 | VHostUserBlk *s = VHOST_USER_BLK(vdev); |
301 | int ret = 0; |
302 | |
303 | if (s->connected) { |
304 | return 0; |
305 | } |
306 | s->connected = true; |
307 | |
308 | s->dev.nvqs = s->num_queues; |
309 | s->dev.vqs = s->vqs; |
310 | s->dev.vq_index = 0; |
311 | s->dev.backend_features = 0; |
312 | |
313 | vhost_dev_set_config_notifier(&s->dev, &blk_ops); |
314 | |
315 | ret = vhost_dev_init(&s->dev, &s->vhost_user, VHOST_BACKEND_TYPE_USER, 0); |
316 | if (ret < 0) { |
317 | error_report("vhost-user-blk: vhost initialization failed: %s" , |
318 | strerror(-ret)); |
319 | return ret; |
320 | } |
321 | |
322 | /* restore vhost state */ |
323 | if (virtio_device_started(vdev, vdev->status)) { |
324 | ret = vhost_user_blk_start(vdev); |
325 | if (ret < 0) { |
326 | error_report("vhost-user-blk: vhost start failed: %s" , |
327 | strerror(-ret)); |
328 | return ret; |
329 | } |
330 | } |
331 | |
332 | return 0; |
333 | } |
334 | |
335 | static void vhost_user_blk_disconnect(DeviceState *dev) |
336 | { |
337 | VirtIODevice *vdev = VIRTIO_DEVICE(dev); |
338 | VHostUserBlk *s = VHOST_USER_BLK(vdev); |
339 | |
340 | if (!s->connected) { |
341 | return; |
342 | } |
343 | s->connected = false; |
344 | |
345 | if (s->dev.started) { |
346 | vhost_user_blk_stop(vdev); |
347 | } |
348 | |
349 | vhost_dev_cleanup(&s->dev); |
350 | } |
351 | |
352 | static gboolean vhost_user_blk_watch(GIOChannel *chan, GIOCondition cond, |
353 | void *opaque) |
354 | { |
355 | DeviceState *dev = opaque; |
356 | VirtIODevice *vdev = VIRTIO_DEVICE(dev); |
357 | VHostUserBlk *s = VHOST_USER_BLK(vdev); |
358 | |
359 | qemu_chr_fe_disconnect(&s->chardev); |
360 | |
361 | return true; |
362 | } |
363 | |
364 | static void vhost_user_blk_event(void *opaque, int 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 | s->watch = qemu_chr_fe_add_watch(&s->chardev, G_IO_HUP, |
377 | vhost_user_blk_watch, dev); |
378 | break; |
379 | case CHR_EVENT_CLOSED: |
380 | vhost_user_blk_disconnect(dev); |
381 | if (s->watch) { |
382 | g_source_remove(s->watch); |
383 | s->watch = 0; |
384 | } |
385 | break; |
386 | } |
387 | } |
388 | |
389 | static void vhost_user_blk_device_realize(DeviceState *dev, Error **errp) |
390 | { |
391 | VirtIODevice *vdev = VIRTIO_DEVICE(dev); |
392 | VHostUserBlk *s = VHOST_USER_BLK(vdev); |
393 | Error *err = NULL; |
394 | int i, ret; |
395 | |
396 | if (!s->chardev.chr) { |
397 | error_setg(errp, "vhost-user-blk: chardev is mandatory" ); |
398 | return; |
399 | } |
400 | |
401 | if (!s->num_queues || s->num_queues > VIRTIO_QUEUE_MAX) { |
402 | error_setg(errp, "vhost-user-blk: invalid number of IO queues" ); |
403 | return; |
404 | } |
405 | |
406 | if (!s->queue_size) { |
407 | error_setg(errp, "vhost-user-blk: queue size must be non-zero" ); |
408 | return; |
409 | } |
410 | |
411 | if (!vhost_user_init(&s->vhost_user, &s->chardev, errp)) { |
412 | return; |
413 | } |
414 | |
415 | virtio_init(vdev, "virtio-blk" , VIRTIO_ID_BLOCK, |
416 | sizeof(struct virtio_blk_config)); |
417 | |
418 | for (i = 0; i < s->num_queues; i++) { |
419 | virtio_add_queue(vdev, s->queue_size, |
420 | vhost_user_blk_handle_output); |
421 | } |
422 | |
423 | s->inflight = g_new0(struct vhost_inflight, 1); |
424 | s->vqs = g_new(struct vhost_virtqueue, s->num_queues); |
425 | s->watch = 0; |
426 | s->connected = false; |
427 | |
428 | qemu_chr_fe_set_handlers(&s->chardev, NULL, NULL, vhost_user_blk_event, |
429 | NULL, (void *)dev, NULL, true); |
430 | |
431 | reconnect: |
432 | if (qemu_chr_fe_wait_connected(&s->chardev, &err) < 0) { |
433 | error_report_err(err); |
434 | goto virtio_err; |
435 | } |
436 | |
437 | /* check whether vhost_user_blk_connect() failed or not */ |
438 | if (!s->connected) { |
439 | goto reconnect; |
440 | } |
441 | |
442 | ret = vhost_dev_get_config(&s->dev, (uint8_t *)&s->blkcfg, |
443 | sizeof(struct virtio_blk_config)); |
444 | if (ret < 0) { |
445 | error_report("vhost-user-blk: get block config failed" ); |
446 | goto reconnect; |
447 | } |
448 | |
449 | if (s->blkcfg.num_queues != s->num_queues) { |
450 | s->blkcfg.num_queues = s->num_queues; |
451 | } |
452 | |
453 | return; |
454 | |
455 | virtio_err: |
456 | g_free(s->vqs); |
457 | g_free(s->inflight); |
458 | virtio_cleanup(vdev); |
459 | vhost_user_cleanup(&s->vhost_user); |
460 | } |
461 | |
462 | static void vhost_user_blk_device_unrealize(DeviceState *dev, Error **errp) |
463 | { |
464 | VirtIODevice *vdev = VIRTIO_DEVICE(dev); |
465 | VHostUserBlk *s = VHOST_USER_BLK(dev); |
466 | |
467 | virtio_set_status(vdev, 0); |
468 | qemu_chr_fe_set_handlers(&s->chardev, NULL, NULL, NULL, |
469 | NULL, NULL, NULL, false); |
470 | vhost_dev_cleanup(&s->dev); |
471 | vhost_dev_free_inflight(s->inflight); |
472 | g_free(s->vqs); |
473 | g_free(s->inflight); |
474 | virtio_cleanup(vdev); |
475 | vhost_user_cleanup(&s->vhost_user); |
476 | } |
477 | |
478 | static void vhost_user_blk_instance_init(Object *obj) |
479 | { |
480 | VHostUserBlk *s = VHOST_USER_BLK(obj); |
481 | |
482 | device_add_bootindex_property(obj, &s->bootindex, "bootindex" , |
483 | "/disk@0,0" , DEVICE(obj), NULL); |
484 | } |
485 | |
486 | static const VMStateDescription vmstate_vhost_user_blk = { |
487 | .name = "vhost-user-blk" , |
488 | .minimum_version_id = 1, |
489 | .version_id = 1, |
490 | .fields = (VMStateField[]) { |
491 | VMSTATE_VIRTIO_DEVICE, |
492 | VMSTATE_END_OF_LIST() |
493 | }, |
494 | }; |
495 | |
496 | static Property vhost_user_blk_properties[] = { |
497 | DEFINE_PROP_CHR("chardev" , VHostUserBlk, chardev), |
498 | DEFINE_PROP_UINT16("num-queues" , VHostUserBlk, num_queues, 1), |
499 | DEFINE_PROP_UINT32("queue-size" , VHostUserBlk, queue_size, 128), |
500 | DEFINE_PROP_BIT("config-wce" , VHostUserBlk, config_wce, 0, true), |
501 | DEFINE_PROP_END_OF_LIST(), |
502 | }; |
503 | |
504 | static void vhost_user_blk_class_init(ObjectClass *klass, void *data) |
505 | { |
506 | DeviceClass *dc = DEVICE_CLASS(klass); |
507 | VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); |
508 | |
509 | dc->props = vhost_user_blk_properties; |
510 | dc->vmsd = &vmstate_vhost_user_blk; |
511 | set_bit(DEVICE_CATEGORY_STORAGE, dc->categories); |
512 | vdc->realize = vhost_user_blk_device_realize; |
513 | vdc->unrealize = vhost_user_blk_device_unrealize; |
514 | vdc->get_config = vhost_user_blk_update_config; |
515 | vdc->set_config = vhost_user_blk_set_config; |
516 | vdc->get_features = vhost_user_blk_get_features; |
517 | vdc->set_status = vhost_user_blk_set_status; |
518 | vdc->reset = vhost_user_blk_reset; |
519 | } |
520 | |
521 | static const TypeInfo vhost_user_blk_info = { |
522 | .name = TYPE_VHOST_USER_BLK, |
523 | .parent = TYPE_VIRTIO_DEVICE, |
524 | .instance_size = sizeof(VHostUserBlk), |
525 | .instance_init = vhost_user_blk_instance_init, |
526 | .class_init = vhost_user_blk_class_init, |
527 | }; |
528 | |
529 | static void virtio_register_types(void) |
530 | { |
531 | type_register_static(&vhost_user_blk_info); |
532 | } |
533 | |
534 | type_init(virtio_register_types) |
535 | |