xref: /openbmc/linux/drivers/vdpa/vdpa.c (revision 48cc39c3)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * vDPA bus.
4  *
5  * Copyright (c) 2020, Red Hat. All rights reserved.
6  *     Author: Jason Wang <jasowang@redhat.com>
7  *
8  */
9 
10 #include <linux/module.h>
11 #include <linux/idr.h>
12 #include <linux/slab.h>
13 #include <linux/vdpa.h>
14 #include <uapi/linux/vdpa.h>
15 #include <net/genetlink.h>
16 #include <linux/mod_devicetable.h>
17 
18 static LIST_HEAD(mdev_head);
19 /* A global mutex that protects vdpa management device and device level operations. */
20 static DEFINE_MUTEX(vdpa_dev_mutex);
21 static DEFINE_IDA(vdpa_index_ida);
22 
23 static struct genl_family vdpa_nl_family;
24 
25 static int vdpa_dev_probe(struct device *d)
26 {
27 	struct vdpa_device *vdev = dev_to_vdpa(d);
28 	struct vdpa_driver *drv = drv_to_vdpa(vdev->dev.driver);
29 	int ret = 0;
30 
31 	if (drv && drv->probe)
32 		ret = drv->probe(vdev);
33 
34 	return ret;
35 }
36 
37 static void vdpa_dev_remove(struct device *d)
38 {
39 	struct vdpa_device *vdev = dev_to_vdpa(d);
40 	struct vdpa_driver *drv = drv_to_vdpa(vdev->dev.driver);
41 
42 	if (drv && drv->remove)
43 		drv->remove(vdev);
44 }
45 
46 static struct bus_type vdpa_bus = {
47 	.name  = "vdpa",
48 	.probe = vdpa_dev_probe,
49 	.remove = vdpa_dev_remove,
50 };
51 
52 static void vdpa_release_dev(struct device *d)
53 {
54 	struct vdpa_device *vdev = dev_to_vdpa(d);
55 	const struct vdpa_config_ops *ops = vdev->config;
56 
57 	if (ops->free)
58 		ops->free(vdev);
59 
60 	ida_simple_remove(&vdpa_index_ida, vdev->index);
61 	kfree(vdev);
62 }
63 
64 /**
65  * __vdpa_alloc_device - allocate and initilaize a vDPA device
66  * This allows driver to some prepartion after device is
67  * initialized but before registered.
68  * @parent: the parent device
69  * @config: the bus operations that is supported by this device
70  * @size: size of the parent structure that contains private data
71  * @name: name of the vdpa device; optional.
72  * @use_va: indicate whether virtual address must be used by this device
73  *
74  * Driver should use vdpa_alloc_device() wrapper macro instead of
75  * using this directly.
76  *
77  * Return: Returns an error when parent/config/dma_dev is not set or fail to get
78  *	   ida.
79  */
80 struct vdpa_device *__vdpa_alloc_device(struct device *parent,
81 					const struct vdpa_config_ops *config,
82 					size_t size, const char *name,
83 					bool use_va)
84 {
85 	struct vdpa_device *vdev;
86 	int err = -EINVAL;
87 
88 	if (!config)
89 		goto err;
90 
91 	if (!!config->dma_map != !!config->dma_unmap)
92 		goto err;
93 
94 	/* It should only work for the device that use on-chip IOMMU */
95 	if (use_va && !(config->dma_map || config->set_map))
96 		goto err;
97 
98 	err = -ENOMEM;
99 	vdev = kzalloc(size, GFP_KERNEL);
100 	if (!vdev)
101 		goto err;
102 
103 	err = ida_alloc(&vdpa_index_ida, GFP_KERNEL);
104 	if (err < 0)
105 		goto err_ida;
106 
107 	vdev->dev.bus = &vdpa_bus;
108 	vdev->dev.parent = parent;
109 	vdev->dev.release = vdpa_release_dev;
110 	vdev->index = err;
111 	vdev->config = config;
112 	vdev->features_valid = false;
113 	vdev->use_va = use_va;
114 
115 	if (name)
116 		err = dev_set_name(&vdev->dev, "%s", name);
117 	else
118 		err = dev_set_name(&vdev->dev, "vdpa%u", vdev->index);
119 	if (err)
120 		goto err_name;
121 
122 	device_initialize(&vdev->dev);
123 
124 	return vdev;
125 
126 err_name:
127 	ida_simple_remove(&vdpa_index_ida, vdev->index);
128 err_ida:
129 	kfree(vdev);
130 err:
131 	return ERR_PTR(err);
132 }
133 EXPORT_SYMBOL_GPL(__vdpa_alloc_device);
134 
135 static int vdpa_name_match(struct device *dev, const void *data)
136 {
137 	struct vdpa_device *vdev = container_of(dev, struct vdpa_device, dev);
138 
139 	return (strcmp(dev_name(&vdev->dev), data) == 0);
140 }
141 
142 static int __vdpa_register_device(struct vdpa_device *vdev, int nvqs)
143 {
144 	struct device *dev;
145 
146 	vdev->nvqs = nvqs;
147 
148 	lockdep_assert_held(&vdpa_dev_mutex);
149 	dev = bus_find_device(&vdpa_bus, NULL, dev_name(&vdev->dev), vdpa_name_match);
150 	if (dev) {
151 		put_device(dev);
152 		return -EEXIST;
153 	}
154 	return device_add(&vdev->dev);
155 }
156 
157 /**
158  * _vdpa_register_device - register a vDPA device with vdpa lock held
159  * Caller must have a succeed call of vdpa_alloc_device() before.
160  * Caller must invoke this routine in the management device dev_add()
161  * callback after setting up valid mgmtdev for this vdpa device.
162  * @vdev: the vdpa device to be registered to vDPA bus
163  * @nvqs: number of virtqueues supported by this device
164  *
165  * Return: Returns an error when fail to add device to vDPA bus
166  */
167 int _vdpa_register_device(struct vdpa_device *vdev, int nvqs)
168 {
169 	if (!vdev->mdev)
170 		return -EINVAL;
171 
172 	return __vdpa_register_device(vdev, nvqs);
173 }
174 EXPORT_SYMBOL_GPL(_vdpa_register_device);
175 
176 /**
177  * vdpa_register_device - register a vDPA device
178  * Callers must have a succeed call of vdpa_alloc_device() before.
179  * @vdev: the vdpa device to be registered to vDPA bus
180  * @nvqs: number of virtqueues supported by this device
181  *
182  * Return: Returns an error when fail to add to vDPA bus
183  */
184 int vdpa_register_device(struct vdpa_device *vdev, int nvqs)
185 {
186 	int err;
187 
188 	mutex_lock(&vdpa_dev_mutex);
189 	err = __vdpa_register_device(vdev, nvqs);
190 	mutex_unlock(&vdpa_dev_mutex);
191 	return err;
192 }
193 EXPORT_SYMBOL_GPL(vdpa_register_device);
194 
195 /**
196  * _vdpa_unregister_device - unregister a vDPA device
197  * Caller must invoke this routine as part of management device dev_del()
198  * callback.
199  * @vdev: the vdpa device to be unregisted from vDPA bus
200  */
201 void _vdpa_unregister_device(struct vdpa_device *vdev)
202 {
203 	lockdep_assert_held(&vdpa_dev_mutex);
204 	WARN_ON(!vdev->mdev);
205 	device_unregister(&vdev->dev);
206 }
207 EXPORT_SYMBOL_GPL(_vdpa_unregister_device);
208 
209 /**
210  * vdpa_unregister_device - unregister a vDPA device
211  * @vdev: the vdpa device to be unregisted from vDPA bus
212  */
213 void vdpa_unregister_device(struct vdpa_device *vdev)
214 {
215 	mutex_lock(&vdpa_dev_mutex);
216 	device_unregister(&vdev->dev);
217 	mutex_unlock(&vdpa_dev_mutex);
218 }
219 EXPORT_SYMBOL_GPL(vdpa_unregister_device);
220 
221 /**
222  * __vdpa_register_driver - register a vDPA device driver
223  * @drv: the vdpa device driver to be registered
224  * @owner: module owner of the driver
225  *
226  * Return: Returns an err when fail to do the registration
227  */
228 int __vdpa_register_driver(struct vdpa_driver *drv, struct module *owner)
229 {
230 	drv->driver.bus = &vdpa_bus;
231 	drv->driver.owner = owner;
232 
233 	return driver_register(&drv->driver);
234 }
235 EXPORT_SYMBOL_GPL(__vdpa_register_driver);
236 
237 /**
238  * vdpa_unregister_driver - unregister a vDPA device driver
239  * @drv: the vdpa device driver to be unregistered
240  */
241 void vdpa_unregister_driver(struct vdpa_driver *drv)
242 {
243 	driver_unregister(&drv->driver);
244 }
245 EXPORT_SYMBOL_GPL(vdpa_unregister_driver);
246 
247 /**
248  * vdpa_mgmtdev_register - register a vdpa management device
249  *
250  * @mdev: Pointer to vdpa management device
251  * vdpa_mgmtdev_register() register a vdpa management device which supports
252  * vdpa device management.
253  * Return: Returns 0 on success or failure when required callback ops are not
254  *         initialized.
255  */
256 int vdpa_mgmtdev_register(struct vdpa_mgmt_dev *mdev)
257 {
258 	if (!mdev->device || !mdev->ops || !mdev->ops->dev_add || !mdev->ops->dev_del)
259 		return -EINVAL;
260 
261 	INIT_LIST_HEAD(&mdev->list);
262 	mutex_lock(&vdpa_dev_mutex);
263 	list_add_tail(&mdev->list, &mdev_head);
264 	mutex_unlock(&vdpa_dev_mutex);
265 	return 0;
266 }
267 EXPORT_SYMBOL_GPL(vdpa_mgmtdev_register);
268 
269 static int vdpa_match_remove(struct device *dev, void *data)
270 {
271 	struct vdpa_device *vdev = container_of(dev, struct vdpa_device, dev);
272 	struct vdpa_mgmt_dev *mdev = vdev->mdev;
273 
274 	if (mdev == data)
275 		mdev->ops->dev_del(mdev, vdev);
276 	return 0;
277 }
278 
279 void vdpa_mgmtdev_unregister(struct vdpa_mgmt_dev *mdev)
280 {
281 	mutex_lock(&vdpa_dev_mutex);
282 
283 	list_del(&mdev->list);
284 
285 	/* Filter out all the entries belong to this management device and delete it. */
286 	bus_for_each_dev(&vdpa_bus, NULL, mdev, vdpa_match_remove);
287 
288 	mutex_unlock(&vdpa_dev_mutex);
289 }
290 EXPORT_SYMBOL_GPL(vdpa_mgmtdev_unregister);
291 
292 static bool mgmtdev_handle_match(const struct vdpa_mgmt_dev *mdev,
293 				 const char *busname, const char *devname)
294 {
295 	/* Bus name is optional for simulated management device, so ignore the
296 	 * device with bus if bus attribute is provided.
297 	 */
298 	if ((busname && !mdev->device->bus) || (!busname && mdev->device->bus))
299 		return false;
300 
301 	if (!busname && strcmp(dev_name(mdev->device), devname) == 0)
302 		return true;
303 
304 	if (busname && (strcmp(mdev->device->bus->name, busname) == 0) &&
305 	    (strcmp(dev_name(mdev->device), devname) == 0))
306 		return true;
307 
308 	return false;
309 }
310 
311 static struct vdpa_mgmt_dev *vdpa_mgmtdev_get_from_attr(struct nlattr **attrs)
312 {
313 	struct vdpa_mgmt_dev *mdev;
314 	const char *busname = NULL;
315 	const char *devname;
316 
317 	if (!attrs[VDPA_ATTR_MGMTDEV_DEV_NAME])
318 		return ERR_PTR(-EINVAL);
319 	devname = nla_data(attrs[VDPA_ATTR_MGMTDEV_DEV_NAME]);
320 	if (attrs[VDPA_ATTR_MGMTDEV_BUS_NAME])
321 		busname = nla_data(attrs[VDPA_ATTR_MGMTDEV_BUS_NAME]);
322 
323 	list_for_each_entry(mdev, &mdev_head, list) {
324 		if (mgmtdev_handle_match(mdev, busname, devname))
325 			return mdev;
326 	}
327 	return ERR_PTR(-ENODEV);
328 }
329 
330 static int vdpa_nl_mgmtdev_handle_fill(struct sk_buff *msg, const struct vdpa_mgmt_dev *mdev)
331 {
332 	if (mdev->device->bus &&
333 	    nla_put_string(msg, VDPA_ATTR_MGMTDEV_BUS_NAME, mdev->device->bus->name))
334 		return -EMSGSIZE;
335 	if (nla_put_string(msg, VDPA_ATTR_MGMTDEV_DEV_NAME, dev_name(mdev->device)))
336 		return -EMSGSIZE;
337 	return 0;
338 }
339 
340 static int vdpa_mgmtdev_fill(const struct vdpa_mgmt_dev *mdev, struct sk_buff *msg,
341 			     u32 portid, u32 seq, int flags)
342 {
343 	u64 supported_classes = 0;
344 	void *hdr;
345 	int i = 0;
346 	int err;
347 
348 	hdr = genlmsg_put(msg, portid, seq, &vdpa_nl_family, flags, VDPA_CMD_MGMTDEV_NEW);
349 	if (!hdr)
350 		return -EMSGSIZE;
351 	err = vdpa_nl_mgmtdev_handle_fill(msg, mdev);
352 	if (err)
353 		goto msg_err;
354 
355 	while (mdev->id_table[i].device) {
356 		supported_classes |= BIT(mdev->id_table[i].device);
357 		i++;
358 	}
359 
360 	if (nla_put_u64_64bit(msg, VDPA_ATTR_MGMTDEV_SUPPORTED_CLASSES,
361 			      supported_classes, VDPA_ATTR_UNSPEC)) {
362 		err = -EMSGSIZE;
363 		goto msg_err;
364 	}
365 
366 	genlmsg_end(msg, hdr);
367 	return 0;
368 
369 msg_err:
370 	genlmsg_cancel(msg, hdr);
371 	return err;
372 }
373 
374 static int vdpa_nl_cmd_mgmtdev_get_doit(struct sk_buff *skb, struct genl_info *info)
375 {
376 	struct vdpa_mgmt_dev *mdev;
377 	struct sk_buff *msg;
378 	int err;
379 
380 	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
381 	if (!msg)
382 		return -ENOMEM;
383 
384 	mutex_lock(&vdpa_dev_mutex);
385 	mdev = vdpa_mgmtdev_get_from_attr(info->attrs);
386 	if (IS_ERR(mdev)) {
387 		mutex_unlock(&vdpa_dev_mutex);
388 		NL_SET_ERR_MSG_MOD(info->extack, "Fail to find the specified mgmt device");
389 		err = PTR_ERR(mdev);
390 		goto out;
391 	}
392 
393 	err = vdpa_mgmtdev_fill(mdev, msg, info->snd_portid, info->snd_seq, 0);
394 	mutex_unlock(&vdpa_dev_mutex);
395 	if (err)
396 		goto out;
397 	err = genlmsg_reply(msg, info);
398 	return err;
399 
400 out:
401 	nlmsg_free(msg);
402 	return err;
403 }
404 
405 static int
406 vdpa_nl_cmd_mgmtdev_get_dumpit(struct sk_buff *msg, struct netlink_callback *cb)
407 {
408 	struct vdpa_mgmt_dev *mdev;
409 	int start = cb->args[0];
410 	int idx = 0;
411 	int err;
412 
413 	mutex_lock(&vdpa_dev_mutex);
414 	list_for_each_entry(mdev, &mdev_head, list) {
415 		if (idx < start) {
416 			idx++;
417 			continue;
418 		}
419 		err = vdpa_mgmtdev_fill(mdev, msg, NETLINK_CB(cb->skb).portid,
420 					cb->nlh->nlmsg_seq, NLM_F_MULTI);
421 		if (err)
422 			goto out;
423 		idx++;
424 	}
425 out:
426 	mutex_unlock(&vdpa_dev_mutex);
427 	cb->args[0] = idx;
428 	return msg->len;
429 }
430 
431 static int vdpa_nl_cmd_dev_add_set_doit(struct sk_buff *skb, struct genl_info *info)
432 {
433 	struct vdpa_mgmt_dev *mdev;
434 	const char *name;
435 	int err = 0;
436 
437 	if (!info->attrs[VDPA_ATTR_DEV_NAME])
438 		return -EINVAL;
439 
440 	name = nla_data(info->attrs[VDPA_ATTR_DEV_NAME]);
441 
442 	mutex_lock(&vdpa_dev_mutex);
443 	mdev = vdpa_mgmtdev_get_from_attr(info->attrs);
444 	if (IS_ERR(mdev)) {
445 		NL_SET_ERR_MSG_MOD(info->extack, "Fail to find the specified management device");
446 		err = PTR_ERR(mdev);
447 		goto err;
448 	}
449 
450 	err = mdev->ops->dev_add(mdev, name);
451 err:
452 	mutex_unlock(&vdpa_dev_mutex);
453 	return err;
454 }
455 
456 static int vdpa_nl_cmd_dev_del_set_doit(struct sk_buff *skb, struct genl_info *info)
457 {
458 	struct vdpa_mgmt_dev *mdev;
459 	struct vdpa_device *vdev;
460 	struct device *dev;
461 	const char *name;
462 	int err = 0;
463 
464 	if (!info->attrs[VDPA_ATTR_DEV_NAME])
465 		return -EINVAL;
466 	name = nla_data(info->attrs[VDPA_ATTR_DEV_NAME]);
467 
468 	mutex_lock(&vdpa_dev_mutex);
469 	dev = bus_find_device(&vdpa_bus, NULL, name, vdpa_name_match);
470 	if (!dev) {
471 		NL_SET_ERR_MSG_MOD(info->extack, "device not found");
472 		err = -ENODEV;
473 		goto dev_err;
474 	}
475 	vdev = container_of(dev, struct vdpa_device, dev);
476 	if (!vdev->mdev) {
477 		NL_SET_ERR_MSG_MOD(info->extack, "Only user created device can be deleted by user");
478 		err = -EINVAL;
479 		goto mdev_err;
480 	}
481 	mdev = vdev->mdev;
482 	mdev->ops->dev_del(mdev, vdev);
483 mdev_err:
484 	put_device(dev);
485 dev_err:
486 	mutex_unlock(&vdpa_dev_mutex);
487 	return err;
488 }
489 
490 static int
491 vdpa_dev_fill(struct vdpa_device *vdev, struct sk_buff *msg, u32 portid, u32 seq,
492 	      int flags, struct netlink_ext_ack *extack)
493 {
494 	u16 max_vq_size;
495 	u32 device_id;
496 	u32 vendor_id;
497 	void *hdr;
498 	int err;
499 
500 	hdr = genlmsg_put(msg, portid, seq, &vdpa_nl_family, flags, VDPA_CMD_DEV_NEW);
501 	if (!hdr)
502 		return -EMSGSIZE;
503 
504 	err = vdpa_nl_mgmtdev_handle_fill(msg, vdev->mdev);
505 	if (err)
506 		goto msg_err;
507 
508 	device_id = vdev->config->get_device_id(vdev);
509 	vendor_id = vdev->config->get_vendor_id(vdev);
510 	max_vq_size = vdev->config->get_vq_num_max(vdev);
511 
512 	err = -EMSGSIZE;
513 	if (nla_put_string(msg, VDPA_ATTR_DEV_NAME, dev_name(&vdev->dev)))
514 		goto msg_err;
515 	if (nla_put_u32(msg, VDPA_ATTR_DEV_ID, device_id))
516 		goto msg_err;
517 	if (nla_put_u32(msg, VDPA_ATTR_DEV_VENDOR_ID, vendor_id))
518 		goto msg_err;
519 	if (nla_put_u32(msg, VDPA_ATTR_DEV_MAX_VQS, vdev->nvqs))
520 		goto msg_err;
521 	if (nla_put_u16(msg, VDPA_ATTR_DEV_MAX_VQ_SIZE, max_vq_size))
522 		goto msg_err;
523 
524 	genlmsg_end(msg, hdr);
525 	return 0;
526 
527 msg_err:
528 	genlmsg_cancel(msg, hdr);
529 	return err;
530 }
531 
532 static int vdpa_nl_cmd_dev_get_doit(struct sk_buff *skb, struct genl_info *info)
533 {
534 	struct vdpa_device *vdev;
535 	struct sk_buff *msg;
536 	const char *devname;
537 	struct device *dev;
538 	int err;
539 
540 	if (!info->attrs[VDPA_ATTR_DEV_NAME])
541 		return -EINVAL;
542 	devname = nla_data(info->attrs[VDPA_ATTR_DEV_NAME]);
543 	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
544 	if (!msg)
545 		return -ENOMEM;
546 
547 	mutex_lock(&vdpa_dev_mutex);
548 	dev = bus_find_device(&vdpa_bus, NULL, devname, vdpa_name_match);
549 	if (!dev) {
550 		NL_SET_ERR_MSG_MOD(info->extack, "device not found");
551 		err = -ENODEV;
552 		goto err;
553 	}
554 	vdev = container_of(dev, struct vdpa_device, dev);
555 	if (!vdev->mdev) {
556 		err = -EINVAL;
557 		goto mdev_err;
558 	}
559 	err = vdpa_dev_fill(vdev, msg, info->snd_portid, info->snd_seq, 0, info->extack);
560 	if (!err)
561 		err = genlmsg_reply(msg, info);
562 mdev_err:
563 	put_device(dev);
564 err:
565 	mutex_unlock(&vdpa_dev_mutex);
566 	if (err)
567 		nlmsg_free(msg);
568 	return err;
569 }
570 
571 struct vdpa_dev_dump_info {
572 	struct sk_buff *msg;
573 	struct netlink_callback *cb;
574 	int start_idx;
575 	int idx;
576 };
577 
578 static int vdpa_dev_dump(struct device *dev, void *data)
579 {
580 	struct vdpa_device *vdev = container_of(dev, struct vdpa_device, dev);
581 	struct vdpa_dev_dump_info *info = data;
582 	int err;
583 
584 	if (!vdev->mdev)
585 		return 0;
586 	if (info->idx < info->start_idx) {
587 		info->idx++;
588 		return 0;
589 	}
590 	err = vdpa_dev_fill(vdev, info->msg, NETLINK_CB(info->cb->skb).portid,
591 			    info->cb->nlh->nlmsg_seq, NLM_F_MULTI, info->cb->extack);
592 	if (err)
593 		return err;
594 
595 	info->idx++;
596 	return 0;
597 }
598 
599 static int vdpa_nl_cmd_dev_get_dumpit(struct sk_buff *msg, struct netlink_callback *cb)
600 {
601 	struct vdpa_dev_dump_info info;
602 
603 	info.msg = msg;
604 	info.cb = cb;
605 	info.start_idx = cb->args[0];
606 	info.idx = 0;
607 
608 	mutex_lock(&vdpa_dev_mutex);
609 	bus_for_each_dev(&vdpa_bus, NULL, &info, vdpa_dev_dump);
610 	mutex_unlock(&vdpa_dev_mutex);
611 	cb->args[0] = info.idx;
612 	return msg->len;
613 }
614 
615 static const struct nla_policy vdpa_nl_policy[VDPA_ATTR_MAX + 1] = {
616 	[VDPA_ATTR_MGMTDEV_BUS_NAME] = { .type = NLA_NUL_STRING },
617 	[VDPA_ATTR_MGMTDEV_DEV_NAME] = { .type = NLA_STRING },
618 	[VDPA_ATTR_DEV_NAME] = { .type = NLA_STRING },
619 };
620 
621 static const struct genl_ops vdpa_nl_ops[] = {
622 	{
623 		.cmd = VDPA_CMD_MGMTDEV_GET,
624 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
625 		.doit = vdpa_nl_cmd_mgmtdev_get_doit,
626 		.dumpit = vdpa_nl_cmd_mgmtdev_get_dumpit,
627 	},
628 	{
629 		.cmd = VDPA_CMD_DEV_NEW,
630 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
631 		.doit = vdpa_nl_cmd_dev_add_set_doit,
632 		.flags = GENL_ADMIN_PERM,
633 	},
634 	{
635 		.cmd = VDPA_CMD_DEV_DEL,
636 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
637 		.doit = vdpa_nl_cmd_dev_del_set_doit,
638 		.flags = GENL_ADMIN_PERM,
639 	},
640 	{
641 		.cmd = VDPA_CMD_DEV_GET,
642 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
643 		.doit = vdpa_nl_cmd_dev_get_doit,
644 		.dumpit = vdpa_nl_cmd_dev_get_dumpit,
645 	},
646 };
647 
648 static struct genl_family vdpa_nl_family __ro_after_init = {
649 	.name = VDPA_GENL_NAME,
650 	.version = VDPA_GENL_VERSION,
651 	.maxattr = VDPA_ATTR_MAX,
652 	.policy = vdpa_nl_policy,
653 	.netnsok = false,
654 	.module = THIS_MODULE,
655 	.ops = vdpa_nl_ops,
656 	.n_ops = ARRAY_SIZE(vdpa_nl_ops),
657 };
658 
659 static int vdpa_init(void)
660 {
661 	int err;
662 
663 	err = bus_register(&vdpa_bus);
664 	if (err)
665 		return err;
666 	err = genl_register_family(&vdpa_nl_family);
667 	if (err)
668 		goto err;
669 	return 0;
670 
671 err:
672 	bus_unregister(&vdpa_bus);
673 	return err;
674 }
675 
676 static void __exit vdpa_exit(void)
677 {
678 	genl_unregister_family(&vdpa_nl_family);
679 	bus_unregister(&vdpa_bus);
680 	ida_destroy(&vdpa_index_ida);
681 }
682 core_initcall(vdpa_init);
683 module_exit(vdpa_exit);
684 
685 MODULE_AUTHOR("Jason Wang <jasowang@redhat.com>");
686 MODULE_LICENSE("GPL v2");
687