xref: /openbmc/linux/drivers/vdpa/vdpa.c (revision ae108c48)
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 #include <linux/virtio_ids.h>
18 
19 static LIST_HEAD(mdev_head);
20 /* A global mutex that protects vdpa management device and device level operations. */
21 static DECLARE_RWSEM(vdpa_dev_lock);
22 static DEFINE_IDA(vdpa_index_ida);
23 
24 void vdpa_set_status(struct vdpa_device *vdev, u8 status)
25 {
26 	down_write(&vdev->cf_lock);
27 	vdev->config->set_status(vdev, status);
28 	up_write(&vdev->cf_lock);
29 }
30 EXPORT_SYMBOL(vdpa_set_status);
31 
32 static struct genl_family vdpa_nl_family;
33 
34 static int vdpa_dev_probe(struct device *d)
35 {
36 	struct vdpa_device *vdev = dev_to_vdpa(d);
37 	struct vdpa_driver *drv = drv_to_vdpa(vdev->dev.driver);
38 	const struct vdpa_config_ops *ops = vdev->config;
39 	u32 max_num, min_num = 1;
40 	int ret = 0;
41 
42 	max_num = ops->get_vq_num_max(vdev);
43 	if (ops->get_vq_num_min)
44 		min_num = ops->get_vq_num_min(vdev);
45 	if (max_num < min_num)
46 		return -EINVAL;
47 
48 	if (drv && drv->probe)
49 		ret = drv->probe(vdev);
50 
51 	return ret;
52 }
53 
54 static void vdpa_dev_remove(struct device *d)
55 {
56 	struct vdpa_device *vdev = dev_to_vdpa(d);
57 	struct vdpa_driver *drv = drv_to_vdpa(vdev->dev.driver);
58 
59 	if (drv && drv->remove)
60 		drv->remove(vdev);
61 }
62 
63 static int vdpa_dev_match(struct device *dev, struct device_driver *drv)
64 {
65 	struct vdpa_device *vdev = dev_to_vdpa(dev);
66 
67 	/* Check override first, and if set, only use the named driver */
68 	if (vdev->driver_override)
69 		return strcmp(vdev->driver_override, drv->name) == 0;
70 
71 	/* Currently devices must be supported by all vDPA bus drivers */
72 	return 1;
73 }
74 
75 static ssize_t driver_override_store(struct device *dev,
76 				     struct device_attribute *attr,
77 				     const char *buf, size_t count)
78 {
79 	struct vdpa_device *vdev = dev_to_vdpa(dev);
80 	int ret;
81 
82 	ret = driver_set_override(dev, &vdev->driver_override, buf, count);
83 	if (ret)
84 		return ret;
85 
86 	return count;
87 }
88 
89 static ssize_t driver_override_show(struct device *dev,
90 				    struct device_attribute *attr, char *buf)
91 {
92 	struct vdpa_device *vdev = dev_to_vdpa(dev);
93 	ssize_t len;
94 
95 	device_lock(dev);
96 	len = snprintf(buf, PAGE_SIZE, "%s\n", vdev->driver_override);
97 	device_unlock(dev);
98 
99 	return len;
100 }
101 static DEVICE_ATTR_RW(driver_override);
102 
103 static struct attribute *vdpa_dev_attrs[] = {
104 	&dev_attr_driver_override.attr,
105 	NULL,
106 };
107 
108 static const struct attribute_group vdpa_dev_group = {
109 	.attrs  = vdpa_dev_attrs,
110 };
111 __ATTRIBUTE_GROUPS(vdpa_dev);
112 
113 static struct bus_type vdpa_bus = {
114 	.name  = "vdpa",
115 	.dev_groups = vdpa_dev_groups,
116 	.match = vdpa_dev_match,
117 	.probe = vdpa_dev_probe,
118 	.remove = vdpa_dev_remove,
119 };
120 
121 static void vdpa_release_dev(struct device *d)
122 {
123 	struct vdpa_device *vdev = dev_to_vdpa(d);
124 	const struct vdpa_config_ops *ops = vdev->config;
125 
126 	if (ops->free)
127 		ops->free(vdev);
128 
129 	ida_simple_remove(&vdpa_index_ida, vdev->index);
130 	kfree(vdev->driver_override);
131 	kfree(vdev);
132 }
133 
134 /**
135  * __vdpa_alloc_device - allocate and initilaize a vDPA device
136  * This allows driver to some prepartion after device is
137  * initialized but before registered.
138  * @parent: the parent device
139  * @config: the bus operations that is supported by this device
140  * @ngroups: number of groups supported by this device
141  * @nas: number of address spaces supported by this device
142  * @size: size of the parent structure that contains private data
143  * @name: name of the vdpa device; optional.
144  * @use_va: indicate whether virtual address must be used by this device
145  *
146  * Driver should use vdpa_alloc_device() wrapper macro instead of
147  * using this directly.
148  *
149  * Return: Returns an error when parent/config/dma_dev is not set or fail to get
150  *	   ida.
151  */
152 struct vdpa_device *__vdpa_alloc_device(struct device *parent,
153 					const struct vdpa_config_ops *config,
154 					unsigned int ngroups, unsigned int nas,
155 					size_t size, const char *name,
156 					bool use_va)
157 {
158 	struct vdpa_device *vdev;
159 	int err = -EINVAL;
160 
161 	if (!config)
162 		goto err;
163 
164 	if (!!config->dma_map != !!config->dma_unmap)
165 		goto err;
166 
167 	/* It should only work for the device that use on-chip IOMMU */
168 	if (use_va && !(config->dma_map || config->set_map))
169 		goto err;
170 
171 	err = -ENOMEM;
172 	vdev = kzalloc(size, GFP_KERNEL);
173 	if (!vdev)
174 		goto err;
175 
176 	err = ida_alloc(&vdpa_index_ida, GFP_KERNEL);
177 	if (err < 0)
178 		goto err_ida;
179 
180 	vdev->dev.bus = &vdpa_bus;
181 	vdev->dev.parent = parent;
182 	vdev->dev.release = vdpa_release_dev;
183 	vdev->index = err;
184 	vdev->config = config;
185 	vdev->features_valid = false;
186 	vdev->use_va = use_va;
187 	vdev->ngroups = ngroups;
188 	vdev->nas = nas;
189 
190 	if (name)
191 		err = dev_set_name(&vdev->dev, "%s", name);
192 	else
193 		err = dev_set_name(&vdev->dev, "vdpa%u", vdev->index);
194 	if (err)
195 		goto err_name;
196 
197 	init_rwsem(&vdev->cf_lock);
198 	device_initialize(&vdev->dev);
199 
200 	return vdev;
201 
202 err_name:
203 	ida_simple_remove(&vdpa_index_ida, vdev->index);
204 err_ida:
205 	kfree(vdev);
206 err:
207 	return ERR_PTR(err);
208 }
209 EXPORT_SYMBOL_GPL(__vdpa_alloc_device);
210 
211 static int vdpa_name_match(struct device *dev, const void *data)
212 {
213 	struct vdpa_device *vdev = container_of(dev, struct vdpa_device, dev);
214 
215 	return (strcmp(dev_name(&vdev->dev), data) == 0);
216 }
217 
218 static int __vdpa_register_device(struct vdpa_device *vdev, u32 nvqs)
219 {
220 	struct device *dev;
221 
222 	vdev->nvqs = nvqs;
223 
224 	lockdep_assert_held(&vdpa_dev_lock);
225 	dev = bus_find_device(&vdpa_bus, NULL, dev_name(&vdev->dev), vdpa_name_match);
226 	if (dev) {
227 		put_device(dev);
228 		return -EEXIST;
229 	}
230 	return device_add(&vdev->dev);
231 }
232 
233 /**
234  * _vdpa_register_device - register a vDPA device with vdpa lock held
235  * Caller must have a succeed call of vdpa_alloc_device() before.
236  * Caller must invoke this routine in the management device dev_add()
237  * callback after setting up valid mgmtdev for this vdpa device.
238  * @vdev: the vdpa device to be registered to vDPA bus
239  * @nvqs: number of virtqueues supported by this device
240  *
241  * Return: Returns an error when fail to add device to vDPA bus
242  */
243 int _vdpa_register_device(struct vdpa_device *vdev, u32 nvqs)
244 {
245 	if (!vdev->mdev)
246 		return -EINVAL;
247 
248 	return __vdpa_register_device(vdev, nvqs);
249 }
250 EXPORT_SYMBOL_GPL(_vdpa_register_device);
251 
252 /**
253  * vdpa_register_device - register a vDPA device
254  * Callers must have a succeed call of vdpa_alloc_device() before.
255  * @vdev: the vdpa device to be registered to vDPA bus
256  * @nvqs: number of virtqueues supported by this device
257  *
258  * Return: Returns an error when fail to add to vDPA bus
259  */
260 int vdpa_register_device(struct vdpa_device *vdev, u32 nvqs)
261 {
262 	int err;
263 
264 	down_write(&vdpa_dev_lock);
265 	err = __vdpa_register_device(vdev, nvqs);
266 	up_write(&vdpa_dev_lock);
267 	return err;
268 }
269 EXPORT_SYMBOL_GPL(vdpa_register_device);
270 
271 /**
272  * _vdpa_unregister_device - unregister a vDPA device
273  * Caller must invoke this routine as part of management device dev_del()
274  * callback.
275  * @vdev: the vdpa device to be unregisted from vDPA bus
276  */
277 void _vdpa_unregister_device(struct vdpa_device *vdev)
278 {
279 	lockdep_assert_held(&vdpa_dev_lock);
280 	WARN_ON(!vdev->mdev);
281 	device_unregister(&vdev->dev);
282 }
283 EXPORT_SYMBOL_GPL(_vdpa_unregister_device);
284 
285 /**
286  * vdpa_unregister_device - unregister a vDPA device
287  * @vdev: the vdpa device to be unregisted from vDPA bus
288  */
289 void vdpa_unregister_device(struct vdpa_device *vdev)
290 {
291 	down_write(&vdpa_dev_lock);
292 	device_unregister(&vdev->dev);
293 	up_write(&vdpa_dev_lock);
294 }
295 EXPORT_SYMBOL_GPL(vdpa_unregister_device);
296 
297 /**
298  * __vdpa_register_driver - register a vDPA device driver
299  * @drv: the vdpa device driver to be registered
300  * @owner: module owner of the driver
301  *
302  * Return: Returns an err when fail to do the registration
303  */
304 int __vdpa_register_driver(struct vdpa_driver *drv, struct module *owner)
305 {
306 	drv->driver.bus = &vdpa_bus;
307 	drv->driver.owner = owner;
308 
309 	return driver_register(&drv->driver);
310 }
311 EXPORT_SYMBOL_GPL(__vdpa_register_driver);
312 
313 /**
314  * vdpa_unregister_driver - unregister a vDPA device driver
315  * @drv: the vdpa device driver to be unregistered
316  */
317 void vdpa_unregister_driver(struct vdpa_driver *drv)
318 {
319 	driver_unregister(&drv->driver);
320 }
321 EXPORT_SYMBOL_GPL(vdpa_unregister_driver);
322 
323 /**
324  * vdpa_mgmtdev_register - register a vdpa management device
325  *
326  * @mdev: Pointer to vdpa management device
327  * vdpa_mgmtdev_register() register a vdpa management device which supports
328  * vdpa device management.
329  * Return: Returns 0 on success or failure when required callback ops are not
330  *         initialized.
331  */
332 int vdpa_mgmtdev_register(struct vdpa_mgmt_dev *mdev)
333 {
334 	if (!mdev->device || !mdev->ops || !mdev->ops->dev_add || !mdev->ops->dev_del)
335 		return -EINVAL;
336 
337 	INIT_LIST_HEAD(&mdev->list);
338 	down_write(&vdpa_dev_lock);
339 	list_add_tail(&mdev->list, &mdev_head);
340 	up_write(&vdpa_dev_lock);
341 	return 0;
342 }
343 EXPORT_SYMBOL_GPL(vdpa_mgmtdev_register);
344 
345 static int vdpa_match_remove(struct device *dev, void *data)
346 {
347 	struct vdpa_device *vdev = container_of(dev, struct vdpa_device, dev);
348 	struct vdpa_mgmt_dev *mdev = vdev->mdev;
349 
350 	if (mdev == data)
351 		mdev->ops->dev_del(mdev, vdev);
352 	return 0;
353 }
354 
355 void vdpa_mgmtdev_unregister(struct vdpa_mgmt_dev *mdev)
356 {
357 	down_write(&vdpa_dev_lock);
358 
359 	list_del(&mdev->list);
360 
361 	/* Filter out all the entries belong to this management device and delete it. */
362 	bus_for_each_dev(&vdpa_bus, NULL, mdev, vdpa_match_remove);
363 
364 	up_write(&vdpa_dev_lock);
365 }
366 EXPORT_SYMBOL_GPL(vdpa_mgmtdev_unregister);
367 
368 static void vdpa_get_config_unlocked(struct vdpa_device *vdev,
369 				     unsigned int offset,
370 				     void *buf, unsigned int len)
371 {
372 	const struct vdpa_config_ops *ops = vdev->config;
373 
374 	/*
375 	 * Config accesses aren't supposed to trigger before features are set.
376 	 * If it does happen we assume a legacy guest.
377 	 */
378 	if (!vdev->features_valid)
379 		vdpa_set_features_unlocked(vdev, 0);
380 	ops->get_config(vdev, offset, buf, len);
381 }
382 
383 /**
384  * vdpa_get_config - Get one or more device configuration fields.
385  * @vdev: vdpa device to operate on
386  * @offset: starting byte offset of the field
387  * @buf: buffer pointer to read to
388  * @len: length of the configuration fields in bytes
389  */
390 void vdpa_get_config(struct vdpa_device *vdev, unsigned int offset,
391 		     void *buf, unsigned int len)
392 {
393 	down_read(&vdev->cf_lock);
394 	vdpa_get_config_unlocked(vdev, offset, buf, len);
395 	up_read(&vdev->cf_lock);
396 }
397 EXPORT_SYMBOL_GPL(vdpa_get_config);
398 
399 /**
400  * vdpa_set_config - Set one or more device configuration fields.
401  * @vdev: vdpa device to operate on
402  * @offset: starting byte offset of the field
403  * @buf: buffer pointer to read from
404  * @length: length of the configuration fields in bytes
405  */
406 void vdpa_set_config(struct vdpa_device *vdev, unsigned int offset,
407 		     const void *buf, unsigned int length)
408 {
409 	down_write(&vdev->cf_lock);
410 	vdev->config->set_config(vdev, offset, buf, length);
411 	up_write(&vdev->cf_lock);
412 }
413 EXPORT_SYMBOL_GPL(vdpa_set_config);
414 
415 static bool mgmtdev_handle_match(const struct vdpa_mgmt_dev *mdev,
416 				 const char *busname, const char *devname)
417 {
418 	/* Bus name is optional for simulated management device, so ignore the
419 	 * device with bus if bus attribute is provided.
420 	 */
421 	if ((busname && !mdev->device->bus) || (!busname && mdev->device->bus))
422 		return false;
423 
424 	if (!busname && strcmp(dev_name(mdev->device), devname) == 0)
425 		return true;
426 
427 	if (busname && (strcmp(mdev->device->bus->name, busname) == 0) &&
428 	    (strcmp(dev_name(mdev->device), devname) == 0))
429 		return true;
430 
431 	return false;
432 }
433 
434 static struct vdpa_mgmt_dev *vdpa_mgmtdev_get_from_attr(struct nlattr **attrs)
435 {
436 	struct vdpa_mgmt_dev *mdev;
437 	const char *busname = NULL;
438 	const char *devname;
439 
440 	if (!attrs[VDPA_ATTR_MGMTDEV_DEV_NAME])
441 		return ERR_PTR(-EINVAL);
442 	devname = nla_data(attrs[VDPA_ATTR_MGMTDEV_DEV_NAME]);
443 	if (attrs[VDPA_ATTR_MGMTDEV_BUS_NAME])
444 		busname = nla_data(attrs[VDPA_ATTR_MGMTDEV_BUS_NAME]);
445 
446 	list_for_each_entry(mdev, &mdev_head, list) {
447 		if (mgmtdev_handle_match(mdev, busname, devname))
448 			return mdev;
449 	}
450 	return ERR_PTR(-ENODEV);
451 }
452 
453 static int vdpa_nl_mgmtdev_handle_fill(struct sk_buff *msg, const struct vdpa_mgmt_dev *mdev)
454 {
455 	if (mdev->device->bus &&
456 	    nla_put_string(msg, VDPA_ATTR_MGMTDEV_BUS_NAME, mdev->device->bus->name))
457 		return -EMSGSIZE;
458 	if (nla_put_string(msg, VDPA_ATTR_MGMTDEV_DEV_NAME, dev_name(mdev->device)))
459 		return -EMSGSIZE;
460 	return 0;
461 }
462 
463 static int vdpa_mgmtdev_fill(const struct vdpa_mgmt_dev *mdev, struct sk_buff *msg,
464 			     u32 portid, u32 seq, int flags)
465 {
466 	u64 supported_classes = 0;
467 	void *hdr;
468 	int i = 0;
469 	int err;
470 
471 	hdr = genlmsg_put(msg, portid, seq, &vdpa_nl_family, flags, VDPA_CMD_MGMTDEV_NEW);
472 	if (!hdr)
473 		return -EMSGSIZE;
474 	err = vdpa_nl_mgmtdev_handle_fill(msg, mdev);
475 	if (err)
476 		goto msg_err;
477 
478 	while (mdev->id_table[i].device) {
479 		if (mdev->id_table[i].device <= 63)
480 			supported_classes |= BIT_ULL(mdev->id_table[i].device);
481 		i++;
482 	}
483 
484 	if (nla_put_u64_64bit(msg, VDPA_ATTR_MGMTDEV_SUPPORTED_CLASSES,
485 			      supported_classes, VDPA_ATTR_UNSPEC)) {
486 		err = -EMSGSIZE;
487 		goto msg_err;
488 	}
489 	if (nla_put_u32(msg, VDPA_ATTR_DEV_MGMTDEV_MAX_VQS,
490 			mdev->max_supported_vqs)) {
491 		err = -EMSGSIZE;
492 		goto msg_err;
493 	}
494 	if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_SUPPORTED_FEATURES,
495 			      mdev->supported_features, VDPA_ATTR_PAD)) {
496 		err = -EMSGSIZE;
497 		goto msg_err;
498 	}
499 
500 	genlmsg_end(msg, hdr);
501 	return 0;
502 
503 msg_err:
504 	genlmsg_cancel(msg, hdr);
505 	return err;
506 }
507 
508 static int vdpa_nl_cmd_mgmtdev_get_doit(struct sk_buff *skb, struct genl_info *info)
509 {
510 	struct vdpa_mgmt_dev *mdev;
511 	struct sk_buff *msg;
512 	int err;
513 
514 	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
515 	if (!msg)
516 		return -ENOMEM;
517 
518 	down_read(&vdpa_dev_lock);
519 	mdev = vdpa_mgmtdev_get_from_attr(info->attrs);
520 	if (IS_ERR(mdev)) {
521 		up_read(&vdpa_dev_lock);
522 		NL_SET_ERR_MSG_MOD(info->extack, "Fail to find the specified mgmt device");
523 		err = PTR_ERR(mdev);
524 		goto out;
525 	}
526 
527 	err = vdpa_mgmtdev_fill(mdev, msg, info->snd_portid, info->snd_seq, 0);
528 	up_read(&vdpa_dev_lock);
529 	if (err)
530 		goto out;
531 	err = genlmsg_reply(msg, info);
532 	return err;
533 
534 out:
535 	nlmsg_free(msg);
536 	return err;
537 }
538 
539 static int
540 vdpa_nl_cmd_mgmtdev_get_dumpit(struct sk_buff *msg, struct netlink_callback *cb)
541 {
542 	struct vdpa_mgmt_dev *mdev;
543 	int start = cb->args[0];
544 	int idx = 0;
545 	int err;
546 
547 	down_read(&vdpa_dev_lock);
548 	list_for_each_entry(mdev, &mdev_head, list) {
549 		if (idx < start) {
550 			idx++;
551 			continue;
552 		}
553 		err = vdpa_mgmtdev_fill(mdev, msg, NETLINK_CB(cb->skb).portid,
554 					cb->nlh->nlmsg_seq, NLM_F_MULTI);
555 		if (err)
556 			goto out;
557 		idx++;
558 	}
559 out:
560 	up_read(&vdpa_dev_lock);
561 	cb->args[0] = idx;
562 	return msg->len;
563 }
564 
565 #define VDPA_DEV_NET_ATTRS_MASK (BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MACADDR) | \
566 				 BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MTU)     | \
567 				 BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MAX_VQP))
568 
569 static int vdpa_nl_cmd_dev_add_set_doit(struct sk_buff *skb, struct genl_info *info)
570 {
571 	struct vdpa_dev_set_config config = {};
572 	struct nlattr **nl_attrs = info->attrs;
573 	struct vdpa_mgmt_dev *mdev;
574 	const u8 *macaddr;
575 	const char *name;
576 	int err = 0;
577 
578 	if (!info->attrs[VDPA_ATTR_DEV_NAME])
579 		return -EINVAL;
580 
581 	name = nla_data(info->attrs[VDPA_ATTR_DEV_NAME]);
582 
583 	if (nl_attrs[VDPA_ATTR_DEV_NET_CFG_MACADDR]) {
584 		macaddr = nla_data(nl_attrs[VDPA_ATTR_DEV_NET_CFG_MACADDR]);
585 		memcpy(config.net.mac, macaddr, sizeof(config.net.mac));
586 		config.mask |= BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MACADDR);
587 	}
588 	if (nl_attrs[VDPA_ATTR_DEV_NET_CFG_MTU]) {
589 		config.net.mtu =
590 			nla_get_u16(nl_attrs[VDPA_ATTR_DEV_NET_CFG_MTU]);
591 		config.mask |= BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MTU);
592 	}
593 	if (nl_attrs[VDPA_ATTR_DEV_NET_CFG_MAX_VQP]) {
594 		config.net.max_vq_pairs =
595 			nla_get_u16(nl_attrs[VDPA_ATTR_DEV_NET_CFG_MAX_VQP]);
596 		if (!config.net.max_vq_pairs) {
597 			NL_SET_ERR_MSG_MOD(info->extack,
598 					   "At least one pair of VQs is required");
599 			return -EINVAL;
600 		}
601 		config.mask |= BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MAX_VQP);
602 	}
603 	if (nl_attrs[VDPA_ATTR_DEV_FEATURES]) {
604 		config.device_features =
605 			nla_get_u64(nl_attrs[VDPA_ATTR_DEV_FEATURES]);
606 		config.mask |= BIT_ULL(VDPA_ATTR_DEV_FEATURES);
607 	}
608 
609 	/* Skip checking capability if user didn't prefer to configure any
610 	 * device networking attributes. It is likely that user might have used
611 	 * a device specific method to configure such attributes or using device
612 	 * default attributes.
613 	 */
614 	if ((config.mask & VDPA_DEV_NET_ATTRS_MASK) &&
615 	    !netlink_capable(skb, CAP_NET_ADMIN))
616 		return -EPERM;
617 
618 	down_write(&vdpa_dev_lock);
619 	mdev = vdpa_mgmtdev_get_from_attr(info->attrs);
620 	if (IS_ERR(mdev)) {
621 		NL_SET_ERR_MSG_MOD(info->extack, "Fail to find the specified management device");
622 		err = PTR_ERR(mdev);
623 		goto err;
624 	}
625 	if ((config.mask & mdev->config_attr_mask) != config.mask) {
626 		NL_SET_ERR_MSG_MOD(info->extack,
627 				   "All provided attributes are not supported");
628 		err = -EOPNOTSUPP;
629 		goto err;
630 	}
631 
632 	err = mdev->ops->dev_add(mdev, name, &config);
633 err:
634 	up_write(&vdpa_dev_lock);
635 	return err;
636 }
637 
638 static int vdpa_nl_cmd_dev_del_set_doit(struct sk_buff *skb, struct genl_info *info)
639 {
640 	struct vdpa_mgmt_dev *mdev;
641 	struct vdpa_device *vdev;
642 	struct device *dev;
643 	const char *name;
644 	int err = 0;
645 
646 	if (!info->attrs[VDPA_ATTR_DEV_NAME])
647 		return -EINVAL;
648 	name = nla_data(info->attrs[VDPA_ATTR_DEV_NAME]);
649 
650 	down_write(&vdpa_dev_lock);
651 	dev = bus_find_device(&vdpa_bus, NULL, name, vdpa_name_match);
652 	if (!dev) {
653 		NL_SET_ERR_MSG_MOD(info->extack, "device not found");
654 		err = -ENODEV;
655 		goto dev_err;
656 	}
657 	vdev = container_of(dev, struct vdpa_device, dev);
658 	if (!vdev->mdev) {
659 		NL_SET_ERR_MSG_MOD(info->extack, "Only user created device can be deleted by user");
660 		err = -EINVAL;
661 		goto mdev_err;
662 	}
663 	mdev = vdev->mdev;
664 	mdev->ops->dev_del(mdev, vdev);
665 mdev_err:
666 	put_device(dev);
667 dev_err:
668 	up_write(&vdpa_dev_lock);
669 	return err;
670 }
671 
672 static int
673 vdpa_dev_fill(struct vdpa_device *vdev, struct sk_buff *msg, u32 portid, u32 seq,
674 	      int flags, struct netlink_ext_ack *extack)
675 {
676 	u16 max_vq_size;
677 	u16 min_vq_size = 1;
678 	u32 device_id;
679 	u32 vendor_id;
680 	void *hdr;
681 	int err;
682 
683 	hdr = genlmsg_put(msg, portid, seq, &vdpa_nl_family, flags, VDPA_CMD_DEV_NEW);
684 	if (!hdr)
685 		return -EMSGSIZE;
686 
687 	err = vdpa_nl_mgmtdev_handle_fill(msg, vdev->mdev);
688 	if (err)
689 		goto msg_err;
690 
691 	device_id = vdev->config->get_device_id(vdev);
692 	vendor_id = vdev->config->get_vendor_id(vdev);
693 	max_vq_size = vdev->config->get_vq_num_max(vdev);
694 	if (vdev->config->get_vq_num_min)
695 		min_vq_size = vdev->config->get_vq_num_min(vdev);
696 
697 	err = -EMSGSIZE;
698 	if (nla_put_string(msg, VDPA_ATTR_DEV_NAME, dev_name(&vdev->dev)))
699 		goto msg_err;
700 	if (nla_put_u32(msg, VDPA_ATTR_DEV_ID, device_id))
701 		goto msg_err;
702 	if (nla_put_u32(msg, VDPA_ATTR_DEV_VENDOR_ID, vendor_id))
703 		goto msg_err;
704 	if (nla_put_u32(msg, VDPA_ATTR_DEV_MAX_VQS, vdev->nvqs))
705 		goto msg_err;
706 	if (nla_put_u16(msg, VDPA_ATTR_DEV_MAX_VQ_SIZE, max_vq_size))
707 		goto msg_err;
708 	if (nla_put_u16(msg, VDPA_ATTR_DEV_MIN_VQ_SIZE, min_vq_size))
709 		goto msg_err;
710 
711 	genlmsg_end(msg, hdr);
712 	return 0;
713 
714 msg_err:
715 	genlmsg_cancel(msg, hdr);
716 	return err;
717 }
718 
719 static int vdpa_nl_cmd_dev_get_doit(struct sk_buff *skb, struct genl_info *info)
720 {
721 	struct vdpa_device *vdev;
722 	struct sk_buff *msg;
723 	const char *devname;
724 	struct device *dev;
725 	int err;
726 
727 	if (!info->attrs[VDPA_ATTR_DEV_NAME])
728 		return -EINVAL;
729 	devname = nla_data(info->attrs[VDPA_ATTR_DEV_NAME]);
730 	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
731 	if (!msg)
732 		return -ENOMEM;
733 
734 	down_read(&vdpa_dev_lock);
735 	dev = bus_find_device(&vdpa_bus, NULL, devname, vdpa_name_match);
736 	if (!dev) {
737 		NL_SET_ERR_MSG_MOD(info->extack, "device not found");
738 		err = -ENODEV;
739 		goto err;
740 	}
741 	vdev = container_of(dev, struct vdpa_device, dev);
742 	if (!vdev->mdev) {
743 		err = -EINVAL;
744 		goto mdev_err;
745 	}
746 	err = vdpa_dev_fill(vdev, msg, info->snd_portid, info->snd_seq, 0, info->extack);
747 	if (err)
748 		goto mdev_err;
749 
750 	err = genlmsg_reply(msg, info);
751 	put_device(dev);
752 	up_read(&vdpa_dev_lock);
753 	return err;
754 
755 mdev_err:
756 	put_device(dev);
757 err:
758 	up_read(&vdpa_dev_lock);
759 	nlmsg_free(msg);
760 	return err;
761 }
762 
763 struct vdpa_dev_dump_info {
764 	struct sk_buff *msg;
765 	struct netlink_callback *cb;
766 	int start_idx;
767 	int idx;
768 };
769 
770 static int vdpa_dev_dump(struct device *dev, void *data)
771 {
772 	struct vdpa_device *vdev = container_of(dev, struct vdpa_device, dev);
773 	struct vdpa_dev_dump_info *info = data;
774 	int err;
775 
776 	if (!vdev->mdev)
777 		return 0;
778 	if (info->idx < info->start_idx) {
779 		info->idx++;
780 		return 0;
781 	}
782 	err = vdpa_dev_fill(vdev, info->msg, NETLINK_CB(info->cb->skb).portid,
783 			    info->cb->nlh->nlmsg_seq, NLM_F_MULTI, info->cb->extack);
784 	if (err)
785 		return err;
786 
787 	info->idx++;
788 	return 0;
789 }
790 
791 static int vdpa_nl_cmd_dev_get_dumpit(struct sk_buff *msg, struct netlink_callback *cb)
792 {
793 	struct vdpa_dev_dump_info info;
794 
795 	info.msg = msg;
796 	info.cb = cb;
797 	info.start_idx = cb->args[0];
798 	info.idx = 0;
799 
800 	down_read(&vdpa_dev_lock);
801 	bus_for_each_dev(&vdpa_bus, NULL, &info, vdpa_dev_dump);
802 	up_read(&vdpa_dev_lock);
803 	cb->args[0] = info.idx;
804 	return msg->len;
805 }
806 
807 static int vdpa_dev_net_mq_config_fill(struct sk_buff *msg, u64 features,
808 				       const struct virtio_net_config *config)
809 {
810 	u16 val_u16;
811 
812 	if ((features & BIT_ULL(VIRTIO_NET_F_MQ)) == 0 &&
813 	    (features & BIT_ULL(VIRTIO_NET_F_RSS)) == 0)
814 		return 0;
815 
816 	val_u16 = __virtio16_to_cpu(true, config->max_virtqueue_pairs);
817 
818 	return nla_put_u16(msg, VDPA_ATTR_DEV_NET_CFG_MAX_VQP, val_u16);
819 }
820 
821 static int vdpa_dev_net_mtu_config_fill(struct sk_buff *msg, u64 features,
822 					const struct virtio_net_config *config)
823 {
824 	u16 val_u16;
825 
826 	if ((features & BIT_ULL(VIRTIO_NET_F_MTU)) == 0)
827 		return 0;
828 
829 	val_u16 = __virtio16_to_cpu(true, config->mtu);
830 
831 	return nla_put_u16(msg, VDPA_ATTR_DEV_NET_CFG_MTU, val_u16);
832 }
833 
834 static int vdpa_dev_net_mac_config_fill(struct sk_buff *msg, u64 features,
835 					const struct virtio_net_config *config)
836 {
837 	if ((features & BIT_ULL(VIRTIO_NET_F_MAC)) == 0)
838 		return 0;
839 
840 	return  nla_put(msg, VDPA_ATTR_DEV_NET_CFG_MACADDR,
841 			sizeof(config->mac), config->mac);
842 }
843 
844 static int vdpa_dev_net_config_fill(struct vdpa_device *vdev, struct sk_buff *msg)
845 {
846 	struct virtio_net_config config = {};
847 	u64 features_device;
848 	u16 val_u16;
849 
850 	vdev->config->get_config(vdev, 0, &config, sizeof(config));
851 
852 	val_u16 = __virtio16_to_cpu(true, config.status);
853 	if (nla_put_u16(msg, VDPA_ATTR_DEV_NET_STATUS, val_u16))
854 		return -EMSGSIZE;
855 
856 	features_device = vdev->config->get_device_features(vdev);
857 
858 	if (nla_put_u64_64bit(msg, VDPA_ATTR_VDPA_DEV_SUPPORTED_FEATURES, features_device,
859 			      VDPA_ATTR_PAD))
860 		return -EMSGSIZE;
861 
862 	if (vdpa_dev_net_mtu_config_fill(msg, features_device, &config))
863 		return -EMSGSIZE;
864 
865 	if (vdpa_dev_net_mac_config_fill(msg, features_device, &config))
866 		return -EMSGSIZE;
867 
868 	return vdpa_dev_net_mq_config_fill(msg, features_device, &config);
869 }
870 
871 static int
872 vdpa_dev_config_fill(struct vdpa_device *vdev, struct sk_buff *msg, u32 portid, u32 seq,
873 		     int flags, struct netlink_ext_ack *extack)
874 {
875 	u64 features_driver;
876 	u8 status = 0;
877 	u32 device_id;
878 	void *hdr;
879 	int err;
880 
881 	down_read(&vdev->cf_lock);
882 	hdr = genlmsg_put(msg, portid, seq, &vdpa_nl_family, flags,
883 			  VDPA_CMD_DEV_CONFIG_GET);
884 	if (!hdr) {
885 		err = -EMSGSIZE;
886 		goto out;
887 	}
888 
889 	if (nla_put_string(msg, VDPA_ATTR_DEV_NAME, dev_name(&vdev->dev))) {
890 		err = -EMSGSIZE;
891 		goto msg_err;
892 	}
893 
894 	device_id = vdev->config->get_device_id(vdev);
895 	if (nla_put_u32(msg, VDPA_ATTR_DEV_ID, device_id)) {
896 		err = -EMSGSIZE;
897 		goto msg_err;
898 	}
899 
900 	/* only read driver features after the feature negotiation is done */
901 	status = vdev->config->get_status(vdev);
902 	if (status & VIRTIO_CONFIG_S_FEATURES_OK) {
903 		features_driver = vdev->config->get_driver_features(vdev);
904 		if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_NEGOTIATED_FEATURES, features_driver,
905 				      VDPA_ATTR_PAD)) {
906 			err = -EMSGSIZE;
907 			goto msg_err;
908 		}
909 	}
910 
911 	switch (device_id) {
912 	case VIRTIO_ID_NET:
913 		err = vdpa_dev_net_config_fill(vdev, msg);
914 		break;
915 	default:
916 		err = -EOPNOTSUPP;
917 		break;
918 	}
919 	if (err)
920 		goto msg_err;
921 
922 	up_read(&vdev->cf_lock);
923 	genlmsg_end(msg, hdr);
924 	return 0;
925 
926 msg_err:
927 	genlmsg_cancel(msg, hdr);
928 out:
929 	up_read(&vdev->cf_lock);
930 	return err;
931 }
932 
933 static int vdpa_fill_stats_rec(struct vdpa_device *vdev, struct sk_buff *msg,
934 			       struct genl_info *info, u32 index)
935 {
936 	struct virtio_net_config config = {};
937 	u64 features;
938 	u16 max_vqp;
939 	u8 status;
940 	int err;
941 
942 	status = vdev->config->get_status(vdev);
943 	if (!(status & VIRTIO_CONFIG_S_FEATURES_OK)) {
944 		NL_SET_ERR_MSG_MOD(info->extack, "feature negotiation not complete");
945 		return -EAGAIN;
946 	}
947 	vdpa_get_config_unlocked(vdev, 0, &config, sizeof(config));
948 
949 	max_vqp = __virtio16_to_cpu(true, config.max_virtqueue_pairs);
950 	if (nla_put_u16(msg, VDPA_ATTR_DEV_NET_CFG_MAX_VQP, max_vqp))
951 		return -EMSGSIZE;
952 
953 	features = vdev->config->get_driver_features(vdev);
954 	if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_NEGOTIATED_FEATURES,
955 			      features, VDPA_ATTR_PAD))
956 		return -EMSGSIZE;
957 
958 	if (nla_put_u32(msg, VDPA_ATTR_DEV_QUEUE_INDEX, index))
959 		return -EMSGSIZE;
960 
961 	err = vdev->config->get_vendor_vq_stats(vdev, index, msg, info->extack);
962 	if (err)
963 		return err;
964 
965 	return 0;
966 }
967 
968 static int vendor_stats_fill(struct vdpa_device *vdev, struct sk_buff *msg,
969 			     struct genl_info *info, u32 index)
970 {
971 	int err;
972 
973 	down_read(&vdev->cf_lock);
974 	if (!vdev->config->get_vendor_vq_stats) {
975 		err = -EOPNOTSUPP;
976 		goto out;
977 	}
978 
979 	err = vdpa_fill_stats_rec(vdev, msg, info, index);
980 out:
981 	up_read(&vdev->cf_lock);
982 	return err;
983 }
984 
985 static int vdpa_dev_vendor_stats_fill(struct vdpa_device *vdev,
986 				      struct sk_buff *msg,
987 				      struct genl_info *info, u32 index)
988 {
989 	u32 device_id;
990 	void *hdr;
991 	int err;
992 	u32 portid = info->snd_portid;
993 	u32 seq = info->snd_seq;
994 	u32 flags = 0;
995 
996 	hdr = genlmsg_put(msg, portid, seq, &vdpa_nl_family, flags,
997 			  VDPA_CMD_DEV_VSTATS_GET);
998 	if (!hdr)
999 		return -EMSGSIZE;
1000 
1001 	if (nla_put_string(msg, VDPA_ATTR_DEV_NAME, dev_name(&vdev->dev))) {
1002 		err = -EMSGSIZE;
1003 		goto undo_msg;
1004 	}
1005 
1006 	device_id = vdev->config->get_device_id(vdev);
1007 	if (nla_put_u32(msg, VDPA_ATTR_DEV_ID, device_id)) {
1008 		err = -EMSGSIZE;
1009 		goto undo_msg;
1010 	}
1011 
1012 	switch (device_id) {
1013 	case VIRTIO_ID_NET:
1014 		if (index > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX) {
1015 			NL_SET_ERR_MSG_MOD(info->extack, "queue index excceeds max value");
1016 			err = -ERANGE;
1017 			break;
1018 		}
1019 
1020 		err = vendor_stats_fill(vdev, msg, info, index);
1021 		break;
1022 	default:
1023 		err = -EOPNOTSUPP;
1024 		break;
1025 	}
1026 	genlmsg_end(msg, hdr);
1027 
1028 	return err;
1029 
1030 undo_msg:
1031 	genlmsg_cancel(msg, hdr);
1032 	return err;
1033 }
1034 
1035 static int vdpa_nl_cmd_dev_config_get_doit(struct sk_buff *skb, struct genl_info *info)
1036 {
1037 	struct vdpa_device *vdev;
1038 	struct sk_buff *msg;
1039 	const char *devname;
1040 	struct device *dev;
1041 	int err;
1042 
1043 	if (!info->attrs[VDPA_ATTR_DEV_NAME])
1044 		return -EINVAL;
1045 	devname = nla_data(info->attrs[VDPA_ATTR_DEV_NAME]);
1046 	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1047 	if (!msg)
1048 		return -ENOMEM;
1049 
1050 	down_read(&vdpa_dev_lock);
1051 	dev = bus_find_device(&vdpa_bus, NULL, devname, vdpa_name_match);
1052 	if (!dev) {
1053 		NL_SET_ERR_MSG_MOD(info->extack, "device not found");
1054 		err = -ENODEV;
1055 		goto dev_err;
1056 	}
1057 	vdev = container_of(dev, struct vdpa_device, dev);
1058 	if (!vdev->mdev) {
1059 		NL_SET_ERR_MSG_MOD(info->extack, "unmanaged vdpa device");
1060 		err = -EINVAL;
1061 		goto mdev_err;
1062 	}
1063 	err = vdpa_dev_config_fill(vdev, msg, info->snd_portid, info->snd_seq,
1064 				   0, info->extack);
1065 	if (!err)
1066 		err = genlmsg_reply(msg, info);
1067 
1068 mdev_err:
1069 	put_device(dev);
1070 dev_err:
1071 	up_read(&vdpa_dev_lock);
1072 	if (err)
1073 		nlmsg_free(msg);
1074 	return err;
1075 }
1076 
1077 static int vdpa_dev_config_dump(struct device *dev, void *data)
1078 {
1079 	struct vdpa_device *vdev = container_of(dev, struct vdpa_device, dev);
1080 	struct vdpa_dev_dump_info *info = data;
1081 	int err;
1082 
1083 	if (!vdev->mdev)
1084 		return 0;
1085 	if (info->idx < info->start_idx) {
1086 		info->idx++;
1087 		return 0;
1088 	}
1089 	err = vdpa_dev_config_fill(vdev, info->msg, NETLINK_CB(info->cb->skb).portid,
1090 				   info->cb->nlh->nlmsg_seq, NLM_F_MULTI,
1091 				   info->cb->extack);
1092 	if (err)
1093 		return err;
1094 
1095 	info->idx++;
1096 	return 0;
1097 }
1098 
1099 static int
1100 vdpa_nl_cmd_dev_config_get_dumpit(struct sk_buff *msg, struct netlink_callback *cb)
1101 {
1102 	struct vdpa_dev_dump_info info;
1103 
1104 	info.msg = msg;
1105 	info.cb = cb;
1106 	info.start_idx = cb->args[0];
1107 	info.idx = 0;
1108 
1109 	down_read(&vdpa_dev_lock);
1110 	bus_for_each_dev(&vdpa_bus, NULL, &info, vdpa_dev_config_dump);
1111 	up_read(&vdpa_dev_lock);
1112 	cb->args[0] = info.idx;
1113 	return msg->len;
1114 }
1115 
1116 static int vdpa_nl_cmd_dev_stats_get_doit(struct sk_buff *skb,
1117 					  struct genl_info *info)
1118 {
1119 	struct vdpa_device *vdev;
1120 	struct sk_buff *msg;
1121 	const char *devname;
1122 	struct device *dev;
1123 	u32 index;
1124 	int err;
1125 
1126 	if (!info->attrs[VDPA_ATTR_DEV_NAME])
1127 		return -EINVAL;
1128 
1129 	if (!info->attrs[VDPA_ATTR_DEV_QUEUE_INDEX])
1130 		return -EINVAL;
1131 
1132 	devname = nla_data(info->attrs[VDPA_ATTR_DEV_NAME]);
1133 	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1134 	if (!msg)
1135 		return -ENOMEM;
1136 
1137 	index = nla_get_u32(info->attrs[VDPA_ATTR_DEV_QUEUE_INDEX]);
1138 	down_read(&vdpa_dev_lock);
1139 	dev = bus_find_device(&vdpa_bus, NULL, devname, vdpa_name_match);
1140 	if (!dev) {
1141 		NL_SET_ERR_MSG_MOD(info->extack, "device not found");
1142 		err = -ENODEV;
1143 		goto dev_err;
1144 	}
1145 	vdev = container_of(dev, struct vdpa_device, dev);
1146 	if (!vdev->mdev) {
1147 		NL_SET_ERR_MSG_MOD(info->extack, "unmanaged vdpa device");
1148 		err = -EINVAL;
1149 		goto mdev_err;
1150 	}
1151 	err = vdpa_dev_vendor_stats_fill(vdev, msg, info, index);
1152 	if (err)
1153 		goto mdev_err;
1154 
1155 	err = genlmsg_reply(msg, info);
1156 
1157 	put_device(dev);
1158 	up_read(&vdpa_dev_lock);
1159 
1160 	return err;
1161 
1162 mdev_err:
1163 	put_device(dev);
1164 dev_err:
1165 	nlmsg_free(msg);
1166 	up_read(&vdpa_dev_lock);
1167 	return err;
1168 }
1169 
1170 static const struct nla_policy vdpa_nl_policy[VDPA_ATTR_MAX + 1] = {
1171 	[VDPA_ATTR_MGMTDEV_BUS_NAME] = { .type = NLA_NUL_STRING },
1172 	[VDPA_ATTR_MGMTDEV_DEV_NAME] = { .type = NLA_STRING },
1173 	[VDPA_ATTR_DEV_NAME] = { .type = NLA_STRING },
1174 	[VDPA_ATTR_DEV_NET_CFG_MACADDR] = NLA_POLICY_ETH_ADDR,
1175 	/* virtio spec 1.1 section 5.1.4.1 for valid MTU range */
1176 	[VDPA_ATTR_DEV_NET_CFG_MTU] = NLA_POLICY_MIN(NLA_U16, 68),
1177 };
1178 
1179 static const struct genl_ops vdpa_nl_ops[] = {
1180 	{
1181 		.cmd = VDPA_CMD_MGMTDEV_GET,
1182 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
1183 		.doit = vdpa_nl_cmd_mgmtdev_get_doit,
1184 		.dumpit = vdpa_nl_cmd_mgmtdev_get_dumpit,
1185 	},
1186 	{
1187 		.cmd = VDPA_CMD_DEV_NEW,
1188 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
1189 		.doit = vdpa_nl_cmd_dev_add_set_doit,
1190 		.flags = GENL_ADMIN_PERM,
1191 	},
1192 	{
1193 		.cmd = VDPA_CMD_DEV_DEL,
1194 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
1195 		.doit = vdpa_nl_cmd_dev_del_set_doit,
1196 		.flags = GENL_ADMIN_PERM,
1197 	},
1198 	{
1199 		.cmd = VDPA_CMD_DEV_GET,
1200 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
1201 		.doit = vdpa_nl_cmd_dev_get_doit,
1202 		.dumpit = vdpa_nl_cmd_dev_get_dumpit,
1203 	},
1204 	{
1205 		.cmd = VDPA_CMD_DEV_CONFIG_GET,
1206 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
1207 		.doit = vdpa_nl_cmd_dev_config_get_doit,
1208 		.dumpit = vdpa_nl_cmd_dev_config_get_dumpit,
1209 	},
1210 	{
1211 		.cmd = VDPA_CMD_DEV_VSTATS_GET,
1212 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
1213 		.doit = vdpa_nl_cmd_dev_stats_get_doit,
1214 		.flags = GENL_ADMIN_PERM,
1215 	},
1216 };
1217 
1218 static struct genl_family vdpa_nl_family __ro_after_init = {
1219 	.name = VDPA_GENL_NAME,
1220 	.version = VDPA_GENL_VERSION,
1221 	.maxattr = VDPA_ATTR_MAX,
1222 	.policy = vdpa_nl_policy,
1223 	.netnsok = false,
1224 	.module = THIS_MODULE,
1225 	.ops = vdpa_nl_ops,
1226 	.n_ops = ARRAY_SIZE(vdpa_nl_ops),
1227 	.resv_start_op = VDPA_CMD_DEV_VSTATS_GET + 1,
1228 };
1229 
1230 static int vdpa_init(void)
1231 {
1232 	int err;
1233 
1234 	err = bus_register(&vdpa_bus);
1235 	if (err)
1236 		return err;
1237 	err = genl_register_family(&vdpa_nl_family);
1238 	if (err)
1239 		goto err;
1240 	return 0;
1241 
1242 err:
1243 	bus_unregister(&vdpa_bus);
1244 	return err;
1245 }
1246 
1247 static void __exit vdpa_exit(void)
1248 {
1249 	genl_unregister_family(&vdpa_nl_family);
1250 	bus_unregister(&vdpa_bus);
1251 	ida_destroy(&vdpa_index_ida);
1252 }
1253 core_initcall(vdpa_init);
1254 module_exit(vdpa_exit);
1255 
1256 MODULE_AUTHOR("Jason Wang <jasowang@redhat.com>");
1257 MODULE_LICENSE("GPL v2");
1258