xref: /linux/drivers/nvdimm/bus.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
4  */
5 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
6 #include <linux/libnvdimm.h>
7 #include <linux/sched/mm.h>
8 #include <linux/vmalloc.h>
9 #include <linux/uaccess.h>
10 #include <linux/module.h>
11 #include <linux/blkdev.h>
12 #include <linux/fcntl.h>
13 #include <linux/async.h>
14 #include <linux/ndctl.h>
15 #include <linux/sched.h>
16 #include <linux/slab.h>
17 #include <linux/cpu.h>
18 #include <linux/fs.h>
19 #include <linux/io.h>
20 #include <linux/mm.h>
21 #include <linux/nd.h>
22 #include "nd-core.h"
23 #include "nd.h"
24 #include "pfn.h"
25 
26 int nvdimm_major;
27 static int nvdimm_bus_major;
28 static DEFINE_IDA(nd_ida);
29 
30 static const struct class nd_class = {
31 	.name = "nd",
32 };
33 
34 static int to_nd_device_type(const struct device *dev)
35 {
36 	if (is_nvdimm(dev))
37 		return ND_DEVICE_DIMM;
38 	else if (is_memory(dev))
39 		return ND_DEVICE_REGION_PMEM;
40 	else if (is_nd_dax(dev))
41 		return ND_DEVICE_DAX_PMEM;
42 	else if (is_nd_region(dev->parent))
43 		return nd_region_to_nstype(to_nd_region(dev->parent));
44 
45 	return 0;
46 }
47 
48 static int nvdimm_bus_uevent(const struct device *dev, struct kobj_uevent_env *env)
49 {
50 	return add_uevent_var(env, "MODALIAS=" ND_DEVICE_MODALIAS_FMT,
51 			to_nd_device_type(dev));
52 }
53 
54 static struct module *to_bus_provider(struct device *dev)
55 {
56 	/* pin bus providers while regions are enabled */
57 	if (is_nd_region(dev)) {
58 		struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
59 
60 		return nvdimm_bus->nd_desc->module;
61 	}
62 	return NULL;
63 }
64 
65 static void nvdimm_bus_probe_start(struct nvdimm_bus *nvdimm_bus)
66 {
67 	nvdimm_bus_lock(&nvdimm_bus->dev);
68 	nvdimm_bus->probe_active++;
69 	nvdimm_bus_unlock(&nvdimm_bus->dev);
70 }
71 
72 static void nvdimm_bus_probe_end(struct nvdimm_bus *nvdimm_bus)
73 {
74 	nvdimm_bus_lock(&nvdimm_bus->dev);
75 	if (--nvdimm_bus->probe_active == 0)
76 		wake_up(&nvdimm_bus->wait);
77 	nvdimm_bus_unlock(&nvdimm_bus->dev);
78 }
79 
80 static int nvdimm_bus_probe(struct device *dev)
81 {
82 	struct nd_device_driver *nd_drv = to_nd_device_driver(dev->driver);
83 	struct module *provider = to_bus_provider(dev);
84 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
85 	int rc;
86 
87 	if (!try_module_get(provider))
88 		return -ENXIO;
89 
90 	dev_dbg(&nvdimm_bus->dev, "START: %s.probe(%s)\n",
91 			dev->driver->name, dev_name(dev));
92 
93 	nvdimm_bus_probe_start(nvdimm_bus);
94 	rc = nd_drv->probe(dev);
95 	if ((rc == 0 || rc == -EOPNOTSUPP) &&
96 			dev->parent && is_nd_region(dev->parent))
97 		nd_region_advance_seeds(to_nd_region(dev->parent), dev);
98 	nvdimm_bus_probe_end(nvdimm_bus);
99 
100 	dev_dbg(&nvdimm_bus->dev, "END: %s.probe(%s) = %d\n", dev->driver->name,
101 			dev_name(dev), rc);
102 
103 	if (rc != 0)
104 		module_put(provider);
105 	return rc;
106 }
107 
108 static void nvdimm_bus_remove(struct device *dev)
109 {
110 	struct nd_device_driver *nd_drv = to_nd_device_driver(dev->driver);
111 	struct module *provider = to_bus_provider(dev);
112 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
113 
114 	if (nd_drv->remove)
115 		nd_drv->remove(dev);
116 
117 	dev_dbg(&nvdimm_bus->dev, "%s.remove(%s)\n", dev->driver->name,
118 			dev_name(dev));
119 	module_put(provider);
120 }
121 
122 static void nvdimm_bus_shutdown(struct device *dev)
123 {
124 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
125 	struct nd_device_driver *nd_drv = NULL;
126 
127 	if (dev->driver)
128 		nd_drv = to_nd_device_driver(dev->driver);
129 
130 	if (nd_drv && nd_drv->shutdown) {
131 		nd_drv->shutdown(dev);
132 		dev_dbg(&nvdimm_bus->dev, "%s.shutdown(%s)\n",
133 				dev->driver->name, dev_name(dev));
134 	}
135 }
136 
137 void nd_device_notify(struct device *dev, enum nvdimm_event event)
138 {
139 	device_lock(dev);
140 	if (dev->driver) {
141 		struct nd_device_driver *nd_drv;
142 
143 		nd_drv = to_nd_device_driver(dev->driver);
144 		if (nd_drv->notify)
145 			nd_drv->notify(dev, event);
146 	}
147 	device_unlock(dev);
148 }
149 EXPORT_SYMBOL(nd_device_notify);
150 
151 void nvdimm_region_notify(struct nd_region *nd_region, enum nvdimm_event event)
152 {
153 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&nd_region->dev);
154 
155 	if (!nvdimm_bus)
156 		return;
157 
158 	/* caller is responsible for holding a reference on the device */
159 	nd_device_notify(&nd_region->dev, event);
160 }
161 EXPORT_SYMBOL_GPL(nvdimm_region_notify);
162 
163 struct clear_badblocks_context {
164 	resource_size_t phys, cleared;
165 };
166 
167 static int nvdimm_clear_badblocks_region(struct device *dev, void *data)
168 {
169 	struct clear_badblocks_context *ctx = data;
170 	struct nd_region *nd_region;
171 	resource_size_t ndr_end;
172 	sector_t sector;
173 
174 	/* make sure device is a region */
175 	if (!is_memory(dev))
176 		return 0;
177 
178 	nd_region = to_nd_region(dev);
179 	ndr_end = nd_region->ndr_start + nd_region->ndr_size - 1;
180 
181 	/* make sure we are in the region */
182 	if (ctx->phys < nd_region->ndr_start ||
183 	    (ctx->phys + ctx->cleared - 1) > ndr_end)
184 		return 0;
185 
186 	sector = (ctx->phys - nd_region->ndr_start) / 512;
187 	badblocks_clear(&nd_region->bb, sector, ctx->cleared / 512);
188 
189 	if (nd_region->bb_state)
190 		sysfs_notify_dirent(nd_region->bb_state);
191 
192 	return 0;
193 }
194 
195 static void nvdimm_clear_badblocks_regions(struct nvdimm_bus *nvdimm_bus,
196 		phys_addr_t phys, u64 cleared)
197 {
198 	struct clear_badblocks_context ctx = {
199 		.phys = phys,
200 		.cleared = cleared,
201 	};
202 
203 	device_for_each_child(&nvdimm_bus->dev, &ctx,
204 			nvdimm_clear_badblocks_region);
205 }
206 
207 static void nvdimm_account_cleared_poison(struct nvdimm_bus *nvdimm_bus,
208 		phys_addr_t phys, u64 cleared)
209 {
210 	if (cleared > 0)
211 		badrange_forget(&nvdimm_bus->badrange, phys, cleared);
212 
213 	if (cleared > 0 && cleared / 512)
214 		nvdimm_clear_badblocks_regions(nvdimm_bus, phys, cleared);
215 }
216 
217 long nvdimm_clear_poison(struct device *dev, phys_addr_t phys,
218 		unsigned int len)
219 {
220 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
221 	struct nvdimm_bus_descriptor *nd_desc;
222 	struct nd_cmd_clear_error clear_err;
223 	struct nd_cmd_ars_cap ars_cap;
224 	u32 clear_err_unit, mask;
225 	unsigned int noio_flag;
226 	int cmd_rc, rc;
227 
228 	if (!nvdimm_bus)
229 		return -ENXIO;
230 
231 	nd_desc = nvdimm_bus->nd_desc;
232 	/*
233 	 * if ndctl does not exist, it's PMEM_LEGACY and
234 	 * we want to just pretend everything is handled.
235 	 */
236 	if (!nd_desc->ndctl)
237 		return len;
238 
239 	memset(&ars_cap, 0, sizeof(ars_cap));
240 	ars_cap.address = phys;
241 	ars_cap.length = len;
242 	noio_flag = memalloc_noio_save();
243 	rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_ARS_CAP, &ars_cap,
244 			sizeof(ars_cap), &cmd_rc);
245 	memalloc_noio_restore(noio_flag);
246 	if (rc < 0)
247 		return rc;
248 	if (cmd_rc < 0)
249 		return cmd_rc;
250 	clear_err_unit = ars_cap.clear_err_unit;
251 	if (!clear_err_unit || !is_power_of_2(clear_err_unit))
252 		return -ENXIO;
253 
254 	mask = clear_err_unit - 1;
255 	if ((phys | len) & mask)
256 		return -ENXIO;
257 	memset(&clear_err, 0, sizeof(clear_err));
258 	clear_err.address = phys;
259 	clear_err.length = len;
260 	noio_flag = memalloc_noio_save();
261 	rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_CLEAR_ERROR, &clear_err,
262 			sizeof(clear_err), &cmd_rc);
263 	memalloc_noio_restore(noio_flag);
264 	if (rc < 0)
265 		return rc;
266 	if (cmd_rc < 0)
267 		return cmd_rc;
268 
269 	nvdimm_account_cleared_poison(nvdimm_bus, phys, clear_err.cleared);
270 
271 	return clear_err.cleared;
272 }
273 EXPORT_SYMBOL_GPL(nvdimm_clear_poison);
274 
275 static int nvdimm_bus_match(struct device *dev, const struct device_driver *drv);
276 
277 static const struct bus_type nvdimm_bus_type = {
278 	.name = "nd",
279 	.uevent = nvdimm_bus_uevent,
280 	.match = nvdimm_bus_match,
281 	.probe = nvdimm_bus_probe,
282 	.remove = nvdimm_bus_remove,
283 	.shutdown = nvdimm_bus_shutdown,
284 };
285 
286 static void nvdimm_bus_release(struct device *dev)
287 {
288 	struct nvdimm_bus *nvdimm_bus;
289 
290 	nvdimm_bus = container_of(dev, struct nvdimm_bus, dev);
291 	ida_free(&nd_ida, nvdimm_bus->id);
292 	kfree(nvdimm_bus);
293 }
294 
295 static const struct device_type nvdimm_bus_dev_type = {
296 	.release = nvdimm_bus_release,
297 	.groups = nvdimm_bus_attribute_groups,
298 };
299 
300 bool is_nvdimm_bus(struct device *dev)
301 {
302 	return dev->type == &nvdimm_bus_dev_type;
303 }
304 
305 struct nvdimm_bus *walk_to_nvdimm_bus(struct device *nd_dev)
306 {
307 	struct device *dev;
308 
309 	for (dev = nd_dev; dev; dev = dev->parent)
310 		if (is_nvdimm_bus(dev))
311 			break;
312 	dev_WARN_ONCE(nd_dev, !dev, "invalid dev, not on nd bus\n");
313 	if (dev)
314 		return to_nvdimm_bus(dev);
315 	return NULL;
316 }
317 
318 struct nvdimm_bus *to_nvdimm_bus(struct device *dev)
319 {
320 	struct nvdimm_bus *nvdimm_bus;
321 
322 	nvdimm_bus = container_of(dev, struct nvdimm_bus, dev);
323 	WARN_ON(!is_nvdimm_bus(dev));
324 	return nvdimm_bus;
325 }
326 EXPORT_SYMBOL_GPL(to_nvdimm_bus);
327 
328 struct nvdimm_bus *nvdimm_to_bus(struct nvdimm *nvdimm)
329 {
330 	return to_nvdimm_bus(nvdimm->dev.parent);
331 }
332 EXPORT_SYMBOL_GPL(nvdimm_to_bus);
333 
334 static struct lock_class_key nvdimm_bus_key;
335 
336 struct nvdimm_bus *nvdimm_bus_register(struct device *parent,
337 		struct nvdimm_bus_descriptor *nd_desc)
338 {
339 	struct nvdimm_bus *nvdimm_bus;
340 	int rc;
341 
342 	nvdimm_bus = kzalloc(sizeof(*nvdimm_bus), GFP_KERNEL);
343 	if (!nvdimm_bus)
344 		return NULL;
345 	INIT_LIST_HEAD(&nvdimm_bus->list);
346 	INIT_LIST_HEAD(&nvdimm_bus->mapping_list);
347 	init_waitqueue_head(&nvdimm_bus->wait);
348 	nvdimm_bus->id = ida_alloc(&nd_ida, GFP_KERNEL);
349 	if (nvdimm_bus->id < 0) {
350 		kfree(nvdimm_bus);
351 		return NULL;
352 	}
353 	mutex_init(&nvdimm_bus->reconfig_mutex);
354 	badrange_init(&nvdimm_bus->badrange);
355 	nvdimm_bus->nd_desc = nd_desc;
356 	nvdimm_bus->dev.parent = parent;
357 	nvdimm_bus->dev.type = &nvdimm_bus_dev_type;
358 	nvdimm_bus->dev.groups = nd_desc->attr_groups;
359 	nvdimm_bus->dev.bus = &nvdimm_bus_type;
360 	nvdimm_bus->dev.of_node = nd_desc->of_node;
361 	device_initialize(&nvdimm_bus->dev);
362 	lockdep_set_class(&nvdimm_bus->dev.mutex, &nvdimm_bus_key);
363 	device_set_pm_not_required(&nvdimm_bus->dev);
364 	rc = dev_set_name(&nvdimm_bus->dev, "ndbus%d", nvdimm_bus->id);
365 	if (rc)
366 		goto err;
367 
368 	rc = device_add(&nvdimm_bus->dev);
369 	if (rc) {
370 		dev_dbg(&nvdimm_bus->dev, "registration failed: %d\n", rc);
371 		goto err;
372 	}
373 
374 	return nvdimm_bus;
375  err:
376 	put_device(&nvdimm_bus->dev);
377 	return NULL;
378 }
379 EXPORT_SYMBOL_GPL(nvdimm_bus_register);
380 
381 void nvdimm_bus_unregister(struct nvdimm_bus *nvdimm_bus)
382 {
383 	if (!nvdimm_bus)
384 		return;
385 	device_unregister(&nvdimm_bus->dev);
386 }
387 EXPORT_SYMBOL_GPL(nvdimm_bus_unregister);
388 
389 static int child_unregister(struct device *dev, void *data)
390 {
391 	/*
392 	 * the singular ndctl class device per bus needs to be
393 	 * "device_destroy"ed, so skip it here
394 	 *
395 	 * i.e. remove classless children
396 	 */
397 	if (dev->class)
398 		return 0;
399 
400 	if (is_nvdimm(dev))
401 		nvdimm_delete(to_nvdimm(dev));
402 	else
403 		nd_device_unregister(dev, ND_SYNC);
404 
405 	return 0;
406 }
407 
408 static void free_badrange_list(struct list_head *badrange_list)
409 {
410 	struct badrange_entry *bre, *next;
411 
412 	list_for_each_entry_safe(bre, next, badrange_list, list) {
413 		list_del(&bre->list);
414 		kfree(bre);
415 	}
416 	list_del_init(badrange_list);
417 }
418 
419 static void nd_bus_remove(struct device *dev)
420 {
421 	struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
422 
423 	mutex_lock(&nvdimm_bus_list_mutex);
424 	list_del_init(&nvdimm_bus->list);
425 	mutex_unlock(&nvdimm_bus_list_mutex);
426 
427 	wait_event(nvdimm_bus->wait,
428 			atomic_read(&nvdimm_bus->ioctl_active) == 0);
429 
430 	nd_synchronize();
431 	device_for_each_child(&nvdimm_bus->dev, NULL, child_unregister);
432 
433 	spin_lock(&nvdimm_bus->badrange.lock);
434 	free_badrange_list(&nvdimm_bus->badrange.list);
435 	spin_unlock(&nvdimm_bus->badrange.lock);
436 
437 	nvdimm_bus_destroy_ndctl(nvdimm_bus);
438 }
439 
440 static int nd_bus_probe(struct device *dev)
441 {
442 	struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
443 	int rc;
444 
445 	rc = nvdimm_bus_create_ndctl(nvdimm_bus);
446 	if (rc)
447 		return rc;
448 
449 	mutex_lock(&nvdimm_bus_list_mutex);
450 	list_add_tail(&nvdimm_bus->list, &nvdimm_bus_list);
451 	mutex_unlock(&nvdimm_bus_list_mutex);
452 
453 	/* enable bus provider attributes to look up their local context */
454 	dev_set_drvdata(dev, nvdimm_bus->nd_desc);
455 
456 	return 0;
457 }
458 
459 static struct nd_device_driver nd_bus_driver = {
460 	.probe = nd_bus_probe,
461 	.remove = nd_bus_remove,
462 	.drv = {
463 		.name = "nd_bus",
464 		.suppress_bind_attrs = true,
465 		.bus = &nvdimm_bus_type,
466 		.owner = THIS_MODULE,
467 		.mod_name = KBUILD_MODNAME,
468 	},
469 };
470 
471 static int nvdimm_bus_match(struct device *dev, const struct device_driver *drv)
472 {
473 	const struct nd_device_driver *nd_drv = to_nd_device_driver(drv);
474 
475 	if (is_nvdimm_bus(dev) && nd_drv == &nd_bus_driver)
476 		return true;
477 
478 	return !!test_bit(to_nd_device_type(dev), &nd_drv->type);
479 }
480 
481 static ASYNC_DOMAIN_EXCLUSIVE(nd_async_domain);
482 
483 void nd_synchronize(void)
484 {
485 	async_synchronize_full_domain(&nd_async_domain);
486 }
487 EXPORT_SYMBOL_GPL(nd_synchronize);
488 
489 static void nd_async_device_register(void *d, async_cookie_t cookie)
490 {
491 	struct device *dev = d;
492 
493 	if (device_add(dev) != 0) {
494 		dev_err(dev, "%s: failed\n", __func__);
495 		put_device(dev);
496 	}
497 	put_device(dev);
498 	if (dev->parent)
499 		put_device(dev->parent);
500 }
501 
502 static void nd_async_device_unregister(void *d, async_cookie_t cookie)
503 {
504 	struct device *dev = d;
505 
506 	/* flush bus operations before delete */
507 	nvdimm_bus_lock(dev);
508 	nvdimm_bus_unlock(dev);
509 
510 	device_unregister(dev);
511 	put_device(dev);
512 }
513 
514 static void __nd_device_register(struct device *dev, bool sync)
515 {
516 	if (!dev)
517 		return;
518 
519 	/*
520 	 * Ensure that region devices always have their NUMA node set as
521 	 * early as possible. This way we are able to make certain that
522 	 * any memory associated with the creation and the creation
523 	 * itself of the region is associated with the correct node.
524 	 */
525 	if (is_nd_region(dev))
526 		set_dev_node(dev, to_nd_region(dev)->numa_node);
527 
528 	dev->bus = &nvdimm_bus_type;
529 	device_set_pm_not_required(dev);
530 	if (dev->parent) {
531 		get_device(dev->parent);
532 		if (dev_to_node(dev) == NUMA_NO_NODE)
533 			set_dev_node(dev, dev_to_node(dev->parent));
534 	}
535 	get_device(dev);
536 
537 	if (sync)
538 		nd_async_device_register(dev, 0);
539 	else
540 		async_schedule_dev_domain(nd_async_device_register, dev,
541 					  &nd_async_domain);
542 }
543 
544 void nd_device_register(struct device *dev)
545 {
546 	__nd_device_register(dev, false);
547 }
548 EXPORT_SYMBOL(nd_device_register);
549 
550 void nd_device_register_sync(struct device *dev)
551 {
552 	__nd_device_register(dev, true);
553 }
554 
555 void nd_device_unregister(struct device *dev, enum nd_async_mode mode)
556 {
557 	bool killed;
558 
559 	switch (mode) {
560 	case ND_ASYNC:
561 		/*
562 		 * In the async case this is being triggered with the
563 		 * device lock held and the unregistration work needs to
564 		 * be moved out of line iff this is thread has won the
565 		 * race to schedule the deletion.
566 		 */
567 		if (!kill_device(dev))
568 			return;
569 
570 		get_device(dev);
571 		async_schedule_domain(nd_async_device_unregister, dev,
572 				&nd_async_domain);
573 		break;
574 	case ND_SYNC:
575 		/*
576 		 * In the sync case the device is being unregistered due
577 		 * to a state change of the parent. Claim the kill state
578 		 * to synchronize against other unregistration requests,
579 		 * or otherwise let the async path handle it if the
580 		 * unregistration was already queued.
581 		 */
582 		device_lock(dev);
583 		killed = kill_device(dev);
584 		device_unlock(dev);
585 
586 		if (!killed)
587 			return;
588 
589 		nd_synchronize();
590 		device_unregister(dev);
591 		break;
592 	}
593 }
594 EXPORT_SYMBOL(nd_device_unregister);
595 
596 /**
597  * __nd_driver_register() - register a region or a namespace driver
598  * @nd_drv: driver to register
599  * @owner: automatically set by nd_driver_register() macro
600  * @mod_name: automatically set by nd_driver_register() macro
601  */
602 int __nd_driver_register(struct nd_device_driver *nd_drv, struct module *owner,
603 		const char *mod_name)
604 {
605 	struct device_driver *drv = &nd_drv->drv;
606 
607 	if (!nd_drv->type) {
608 		pr_debug("driver type bitmask not set (%ps)\n",
609 				__builtin_return_address(0));
610 		return -EINVAL;
611 	}
612 
613 	if (!nd_drv->probe) {
614 		pr_debug("%s ->probe() must be specified\n", mod_name);
615 		return -EINVAL;
616 	}
617 
618 	drv->bus = &nvdimm_bus_type;
619 	drv->owner = owner;
620 	drv->mod_name = mod_name;
621 
622 	return driver_register(drv);
623 }
624 EXPORT_SYMBOL(__nd_driver_register);
625 
626 void nvdimm_check_and_set_ro(struct gendisk *disk)
627 {
628 	struct device *dev = disk_to_dev(disk)->parent;
629 	struct nd_region *nd_region = to_nd_region(dev->parent);
630 	int disk_ro = get_disk_ro(disk);
631 
632 	/* catch the disk up with the region ro state */
633 	if (disk_ro == nd_region->ro)
634 		return;
635 
636 	dev_info(dev, "%s read-%s, marking %s read-%s\n",
637 		 dev_name(&nd_region->dev), nd_region->ro ? "only" : "write",
638 		 disk->disk_name, nd_region->ro ? "only" : "write");
639 	set_disk_ro(disk, nd_region->ro);
640 }
641 EXPORT_SYMBOL(nvdimm_check_and_set_ro);
642 
643 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
644 		char *buf)
645 {
646 	return sprintf(buf, ND_DEVICE_MODALIAS_FMT "\n",
647 			to_nd_device_type(dev));
648 }
649 static DEVICE_ATTR_RO(modalias);
650 
651 static ssize_t devtype_show(struct device *dev, struct device_attribute *attr,
652 		char *buf)
653 {
654 	return sprintf(buf, "%s\n", dev->type->name);
655 }
656 static DEVICE_ATTR_RO(devtype);
657 
658 static struct attribute *nd_device_attributes[] = {
659 	&dev_attr_modalias.attr,
660 	&dev_attr_devtype.attr,
661 	NULL,
662 };
663 
664 /*
665  * nd_device_attribute_group - generic attributes for all devices on an nd bus
666  */
667 const struct attribute_group nd_device_attribute_group = {
668 	.attrs = nd_device_attributes,
669 };
670 
671 static ssize_t numa_node_show(struct device *dev,
672 		struct device_attribute *attr, char *buf)
673 {
674 	return sprintf(buf, "%d\n", dev_to_node(dev));
675 }
676 static DEVICE_ATTR_RO(numa_node);
677 
678 static int nvdimm_dev_to_target_node(struct device *dev)
679 {
680 	struct device *parent = dev->parent;
681 	struct nd_region *nd_region = NULL;
682 
683 	if (is_nd_region(dev))
684 		nd_region = to_nd_region(dev);
685 	else if (parent && is_nd_region(parent))
686 		nd_region = to_nd_region(parent);
687 
688 	if (!nd_region)
689 		return NUMA_NO_NODE;
690 	return nd_region->target_node;
691 }
692 
693 static ssize_t target_node_show(struct device *dev,
694 		struct device_attribute *attr, char *buf)
695 {
696 	return sprintf(buf, "%d\n", nvdimm_dev_to_target_node(dev));
697 }
698 static DEVICE_ATTR_RO(target_node);
699 
700 static struct attribute *nd_numa_attributes[] = {
701 	&dev_attr_numa_node.attr,
702 	&dev_attr_target_node.attr,
703 	NULL,
704 };
705 
706 static umode_t nd_numa_attr_visible(struct kobject *kobj, struct attribute *a,
707 		int n)
708 {
709 	struct device *dev = container_of(kobj, typeof(*dev), kobj);
710 
711 	if (!IS_ENABLED(CONFIG_NUMA))
712 		return 0;
713 
714 	if (a == &dev_attr_target_node.attr &&
715 			nvdimm_dev_to_target_node(dev) == NUMA_NO_NODE)
716 		return 0;
717 
718 	return a->mode;
719 }
720 
721 /*
722  * nd_numa_attribute_group - NUMA attributes for all devices on an nd bus
723  */
724 const struct attribute_group nd_numa_attribute_group = {
725 	.attrs = nd_numa_attributes,
726 	.is_visible = nd_numa_attr_visible,
727 };
728 
729 static void ndctl_release(struct device *dev)
730 {
731 	kfree(dev);
732 }
733 
734 static struct lock_class_key nvdimm_ndctl_key;
735 
736 int nvdimm_bus_create_ndctl(struct nvdimm_bus *nvdimm_bus)
737 {
738 	dev_t devt = MKDEV(nvdimm_bus_major, nvdimm_bus->id);
739 	struct device *dev;
740 	int rc;
741 
742 	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
743 	if (!dev)
744 		return -ENOMEM;
745 	device_initialize(dev);
746 	lockdep_set_class(&dev->mutex, &nvdimm_ndctl_key);
747 	device_set_pm_not_required(dev);
748 	dev->class = &nd_class;
749 	dev->parent = &nvdimm_bus->dev;
750 	dev->devt = devt;
751 	dev->release = ndctl_release;
752 	rc = dev_set_name(dev, "ndctl%d", nvdimm_bus->id);
753 	if (rc)
754 		goto err;
755 
756 	rc = device_add(dev);
757 	if (rc) {
758 		dev_dbg(&nvdimm_bus->dev, "failed to register ndctl%d: %d\n",
759 				nvdimm_bus->id, rc);
760 		goto err;
761 	}
762 	return 0;
763 
764 err:
765 	put_device(dev);
766 	return rc;
767 }
768 
769 void nvdimm_bus_destroy_ndctl(struct nvdimm_bus *nvdimm_bus)
770 {
771 	device_destroy(&nd_class, MKDEV(nvdimm_bus_major, nvdimm_bus->id));
772 }
773 
774 static const struct nd_cmd_desc __nd_cmd_dimm_descs[] = {
775 	[ND_CMD_IMPLEMENTED] = { },
776 	[ND_CMD_SMART] = {
777 		.out_num = 2,
778 		.out_sizes = { 4, 128, },
779 	},
780 	[ND_CMD_SMART_THRESHOLD] = {
781 		.out_num = 2,
782 		.out_sizes = { 4, 8, },
783 	},
784 	[ND_CMD_DIMM_FLAGS] = {
785 		.out_num = 2,
786 		.out_sizes = { 4, 4 },
787 	},
788 	[ND_CMD_GET_CONFIG_SIZE] = {
789 		.out_num = 3,
790 		.out_sizes = { 4, 4, 4, },
791 	},
792 	[ND_CMD_GET_CONFIG_DATA] = {
793 		.in_num = 2,
794 		.in_sizes = { 4, 4, },
795 		.out_num = 2,
796 		.out_sizes = { 4, UINT_MAX, },
797 	},
798 	[ND_CMD_SET_CONFIG_DATA] = {
799 		.in_num = 3,
800 		.in_sizes = { 4, 4, UINT_MAX, },
801 		.out_num = 1,
802 		.out_sizes = { 4, },
803 	},
804 	[ND_CMD_VENDOR] = {
805 		.in_num = 3,
806 		.in_sizes = { 4, 4, UINT_MAX, },
807 		.out_num = 3,
808 		.out_sizes = { 4, 4, UINT_MAX, },
809 	},
810 	[ND_CMD_CALL] = {
811 		.in_num = 2,
812 		.in_sizes = { sizeof(struct nd_cmd_pkg), UINT_MAX, },
813 		.out_num = 1,
814 		.out_sizes = { UINT_MAX, },
815 	},
816 };
817 
818 const struct nd_cmd_desc *nd_cmd_dimm_desc(int cmd)
819 {
820 	if (cmd < ARRAY_SIZE(__nd_cmd_dimm_descs))
821 		return &__nd_cmd_dimm_descs[cmd];
822 	return NULL;
823 }
824 EXPORT_SYMBOL_GPL(nd_cmd_dimm_desc);
825 
826 static const struct nd_cmd_desc __nd_cmd_bus_descs[] = {
827 	[ND_CMD_IMPLEMENTED] = { },
828 	[ND_CMD_ARS_CAP] = {
829 		.in_num = 2,
830 		.in_sizes = { 8, 8, },
831 		.out_num = 4,
832 		.out_sizes = { 4, 4, 4, 4, },
833 	},
834 	[ND_CMD_ARS_START] = {
835 		.in_num = 5,
836 		.in_sizes = { 8, 8, 2, 1, 5, },
837 		.out_num = 2,
838 		.out_sizes = { 4, 4, },
839 	},
840 	[ND_CMD_ARS_STATUS] = {
841 		.out_num = 3,
842 		.out_sizes = { 4, 4, UINT_MAX, },
843 	},
844 	[ND_CMD_CLEAR_ERROR] = {
845 		.in_num = 2,
846 		.in_sizes = { 8, 8, },
847 		.out_num = 3,
848 		.out_sizes = { 4, 4, 8, },
849 	},
850 	[ND_CMD_CALL] = {
851 		.in_num = 2,
852 		.in_sizes = { sizeof(struct nd_cmd_pkg), UINT_MAX, },
853 		.out_num = 1,
854 		.out_sizes = { UINT_MAX, },
855 	},
856 };
857 
858 const struct nd_cmd_desc *nd_cmd_bus_desc(int cmd)
859 {
860 	if (cmd < ARRAY_SIZE(__nd_cmd_bus_descs))
861 		return &__nd_cmd_bus_descs[cmd];
862 	return NULL;
863 }
864 EXPORT_SYMBOL_GPL(nd_cmd_bus_desc);
865 
866 u32 nd_cmd_in_size(struct nvdimm *nvdimm, int cmd,
867 		const struct nd_cmd_desc *desc, int idx, void *buf)
868 {
869 	if (idx >= desc->in_num)
870 		return UINT_MAX;
871 
872 	if (desc->in_sizes[idx] < UINT_MAX)
873 		return desc->in_sizes[idx];
874 
875 	if (nvdimm && cmd == ND_CMD_SET_CONFIG_DATA && idx == 2) {
876 		struct nd_cmd_set_config_hdr *hdr = buf;
877 
878 		return hdr->in_length;
879 	} else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2) {
880 		struct nd_cmd_vendor_hdr *hdr = buf;
881 
882 		return hdr->in_length;
883 	} else if (cmd == ND_CMD_CALL) {
884 		struct nd_cmd_pkg *pkg = buf;
885 
886 		return pkg->nd_size_in;
887 	}
888 
889 	return UINT_MAX;
890 }
891 EXPORT_SYMBOL_GPL(nd_cmd_in_size);
892 
893 u32 nd_cmd_out_size(struct nvdimm *nvdimm, int cmd,
894 		const struct nd_cmd_desc *desc, int idx, const u32 *in_field,
895 		const u32 *out_field, unsigned long remainder)
896 {
897 	if (idx >= desc->out_num)
898 		return UINT_MAX;
899 
900 	if (desc->out_sizes[idx] < UINT_MAX)
901 		return desc->out_sizes[idx];
902 
903 	if (nvdimm && cmd == ND_CMD_GET_CONFIG_DATA && idx == 1)
904 		return in_field[1];
905 	else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2)
906 		return out_field[1];
907 	else if (!nvdimm && cmd == ND_CMD_ARS_STATUS && idx == 2) {
908 		/*
909 		 * Per table 9-276 ARS Data in ACPI 6.1, out_field[1] is
910 		 * "Size of Output Buffer in bytes, including this
911 		 * field."
912 		 */
913 		if (out_field[1] < 4)
914 			return 0;
915 		/*
916 		 * ACPI 6.1 is ambiguous if 'status' is included in the
917 		 * output size. If we encounter an output size that
918 		 * overshoots the remainder by 4 bytes, assume it was
919 		 * including 'status'.
920 		 */
921 		if (out_field[1] - 4 == remainder)
922 			return remainder;
923 		return out_field[1] - 8;
924 	} else if (cmd == ND_CMD_CALL) {
925 		struct nd_cmd_pkg *pkg = (struct nd_cmd_pkg *) in_field;
926 
927 		return pkg->nd_size_out;
928 	}
929 
930 
931 	return UINT_MAX;
932 }
933 EXPORT_SYMBOL_GPL(nd_cmd_out_size);
934 
935 void wait_nvdimm_bus_probe_idle(struct device *dev)
936 {
937 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
938 
939 	do {
940 		if (nvdimm_bus->probe_active == 0)
941 			break;
942 		nvdimm_bus_unlock(dev);
943 		device_unlock(dev);
944 		wait_event(nvdimm_bus->wait,
945 				nvdimm_bus->probe_active == 0);
946 		device_lock(dev);
947 		nvdimm_bus_lock(dev);
948 	} while (true);
949 }
950 
951 static int nd_pmem_forget_poison_check(struct device *dev, void *data)
952 {
953 	struct nd_cmd_clear_error *clear_err =
954 		(struct nd_cmd_clear_error *)data;
955 	struct nd_btt *nd_btt = is_nd_btt(dev) ? to_nd_btt(dev) : NULL;
956 	struct nd_pfn *nd_pfn = is_nd_pfn(dev) ? to_nd_pfn(dev) : NULL;
957 	struct nd_dax *nd_dax = is_nd_dax(dev) ? to_nd_dax(dev) : NULL;
958 	struct nd_namespace_common *ndns = NULL;
959 	struct nd_namespace_io *nsio;
960 	resource_size_t offset = 0, end_trunc = 0, start, end, pstart, pend;
961 
962 	if (nd_dax || !dev->driver)
963 		return 0;
964 
965 	start = clear_err->address;
966 	end = clear_err->address + clear_err->cleared - 1;
967 
968 	if (nd_btt || nd_pfn || nd_dax) {
969 		if (nd_btt)
970 			ndns = nd_btt->ndns;
971 		else if (nd_pfn)
972 			ndns = nd_pfn->ndns;
973 		else if (nd_dax)
974 			ndns = nd_dax->nd_pfn.ndns;
975 
976 		if (!ndns)
977 			return 0;
978 	} else
979 		ndns = to_ndns(dev);
980 
981 	nsio = to_nd_namespace_io(&ndns->dev);
982 	pstart = nsio->res.start + offset;
983 	pend = nsio->res.end - end_trunc;
984 
985 	if ((pstart >= start) && (pend <= end))
986 		return -EBUSY;
987 
988 	return 0;
989 
990 }
991 
992 static int nd_ns_forget_poison_check(struct device *dev, void *data)
993 {
994 	return device_for_each_child(dev, data, nd_pmem_forget_poison_check);
995 }
996 
997 /* set_config requires an idle interleave set */
998 static int nd_cmd_clear_to_send(struct nvdimm_bus *nvdimm_bus,
999 		struct nvdimm *nvdimm, unsigned int cmd, void *data)
1000 {
1001 	struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
1002 
1003 	/* ask the bus provider if it would like to block this request */
1004 	if (nd_desc->clear_to_send) {
1005 		int rc = nd_desc->clear_to_send(nd_desc, nvdimm, cmd, data);
1006 
1007 		if (rc)
1008 			return rc;
1009 	}
1010 
1011 	/* require clear error to go through the pmem driver */
1012 	if (!nvdimm && cmd == ND_CMD_CLEAR_ERROR)
1013 		return device_for_each_child(&nvdimm_bus->dev, data,
1014 				nd_ns_forget_poison_check);
1015 
1016 	if (!nvdimm || cmd != ND_CMD_SET_CONFIG_DATA)
1017 		return 0;
1018 
1019 	/* prevent label manipulation while the kernel owns label updates */
1020 	wait_nvdimm_bus_probe_idle(&nvdimm_bus->dev);
1021 	if (atomic_read(&nvdimm->busy))
1022 		return -EBUSY;
1023 	return 0;
1024 }
1025 
1026 static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm,
1027 		int read_only, unsigned int ioctl_cmd, unsigned long arg)
1028 {
1029 	struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
1030 	const struct nd_cmd_desc *desc = NULL;
1031 	unsigned int cmd = _IOC_NR(ioctl_cmd);
1032 	struct device *dev = &nvdimm_bus->dev;
1033 	void __user *p = (void __user *) arg;
1034 	char *out_env = NULL, *in_env = NULL;
1035 	const char *cmd_name, *dimm_name;
1036 	u32 in_len = 0, out_len = 0;
1037 	unsigned int func = cmd;
1038 	unsigned long cmd_mask;
1039 	struct nd_cmd_pkg pkg;
1040 	int rc, i, cmd_rc;
1041 	void *buf = NULL;
1042 	u64 buf_len = 0;
1043 
1044 	if (nvdimm) {
1045 		desc = nd_cmd_dimm_desc(cmd);
1046 		cmd_name = nvdimm_cmd_name(cmd);
1047 		cmd_mask = nvdimm->cmd_mask;
1048 		dimm_name = dev_name(&nvdimm->dev);
1049 	} else {
1050 		desc = nd_cmd_bus_desc(cmd);
1051 		cmd_name = nvdimm_bus_cmd_name(cmd);
1052 		cmd_mask = nd_desc->cmd_mask;
1053 		dimm_name = "bus";
1054 	}
1055 
1056 	/* Validate command family support against bus declared support */
1057 	if (cmd == ND_CMD_CALL) {
1058 		unsigned long *mask;
1059 
1060 		if (copy_from_user(&pkg, p, sizeof(pkg)))
1061 			return -EFAULT;
1062 
1063 		if (nvdimm) {
1064 			if (pkg.nd_family > NVDIMM_FAMILY_MAX)
1065 				return -EINVAL;
1066 			mask = &nd_desc->dimm_family_mask;
1067 		} else {
1068 			if (pkg.nd_family > NVDIMM_BUS_FAMILY_MAX)
1069 				return -EINVAL;
1070 			mask = &nd_desc->bus_family_mask;
1071 		}
1072 
1073 		if (!test_bit(pkg.nd_family, mask))
1074 			return -EINVAL;
1075 	}
1076 
1077 	if (!desc ||
1078 	    (desc->out_num + desc->in_num == 0) ||
1079 	    cmd > ND_CMD_CALL ||
1080 	    !test_bit(cmd, &cmd_mask))
1081 		return -ENOTTY;
1082 
1083 	/* fail write commands (when read-only) */
1084 	if (read_only)
1085 		switch (cmd) {
1086 		case ND_CMD_VENDOR:
1087 		case ND_CMD_SET_CONFIG_DATA:
1088 		case ND_CMD_ARS_START:
1089 		case ND_CMD_CLEAR_ERROR:
1090 		case ND_CMD_CALL:
1091 			dev_dbg(dev, "'%s' command while read-only.\n",
1092 					nvdimm ? nvdimm_cmd_name(cmd)
1093 					: nvdimm_bus_cmd_name(cmd));
1094 			return -EPERM;
1095 		default:
1096 			break;
1097 		}
1098 
1099 	/* process an input envelope */
1100 	in_env = kzalloc(ND_CMD_MAX_ENVELOPE, GFP_KERNEL);
1101 	if (!in_env)
1102 		return -ENOMEM;
1103 	for (i = 0; i < desc->in_num; i++) {
1104 		u32 in_size, copy;
1105 
1106 		in_size = nd_cmd_in_size(nvdimm, cmd, desc, i, in_env);
1107 		if (in_size == UINT_MAX) {
1108 			dev_err(dev, "%s:%s unknown input size cmd: %s field: %d\n",
1109 					__func__, dimm_name, cmd_name, i);
1110 			rc = -ENXIO;
1111 			goto out;
1112 		}
1113 		if (in_len < ND_CMD_MAX_ENVELOPE)
1114 			copy = min_t(u32, ND_CMD_MAX_ENVELOPE - in_len, in_size);
1115 		else
1116 			copy = 0;
1117 		if (copy && copy_from_user(&in_env[in_len], p + in_len, copy)) {
1118 			rc = -EFAULT;
1119 			goto out;
1120 		}
1121 		in_len += in_size;
1122 	}
1123 
1124 	if (cmd == ND_CMD_CALL) {
1125 		func = pkg.nd_command;
1126 		dev_dbg(dev, "%s, idx: %llu, in: %u, out: %u, len %llu\n",
1127 				dimm_name, pkg.nd_command,
1128 				in_len, out_len, buf_len);
1129 	}
1130 
1131 	/* process an output envelope */
1132 	out_env = kzalloc(ND_CMD_MAX_ENVELOPE, GFP_KERNEL);
1133 	if (!out_env) {
1134 		rc = -ENOMEM;
1135 		goto out;
1136 	}
1137 
1138 	for (i = 0; i < desc->out_num; i++) {
1139 		u32 out_size = nd_cmd_out_size(nvdimm, cmd, desc, i,
1140 				(u32 *) in_env, (u32 *) out_env, 0);
1141 		u32 copy;
1142 
1143 		if (out_size == UINT_MAX) {
1144 			dev_dbg(dev, "%s unknown output size cmd: %s field: %d\n",
1145 					dimm_name, cmd_name, i);
1146 			rc = -EFAULT;
1147 			goto out;
1148 		}
1149 		if (out_len < ND_CMD_MAX_ENVELOPE)
1150 			copy = min_t(u32, ND_CMD_MAX_ENVELOPE - out_len, out_size);
1151 		else
1152 			copy = 0;
1153 		if (copy && copy_from_user(&out_env[out_len],
1154 					p + in_len + out_len, copy)) {
1155 			rc = -EFAULT;
1156 			goto out;
1157 		}
1158 		out_len += out_size;
1159 	}
1160 
1161 	buf_len = (u64) out_len + (u64) in_len;
1162 	if (buf_len > ND_IOCTL_MAX_BUFLEN) {
1163 		dev_dbg(dev, "%s cmd: %s buf_len: %llu > %d\n", dimm_name,
1164 				cmd_name, buf_len, ND_IOCTL_MAX_BUFLEN);
1165 		rc = -EINVAL;
1166 		goto out;
1167 	}
1168 
1169 	buf = vmalloc(buf_len);
1170 	if (!buf) {
1171 		rc = -ENOMEM;
1172 		goto out;
1173 	}
1174 
1175 	if (copy_from_user(buf, p, buf_len)) {
1176 		rc = -EFAULT;
1177 		goto out;
1178 	}
1179 
1180 	device_lock(dev);
1181 	nvdimm_bus_lock(dev);
1182 	rc = nd_cmd_clear_to_send(nvdimm_bus, nvdimm, func, buf);
1183 	if (rc)
1184 		goto out_unlock;
1185 
1186 	rc = nd_desc->ndctl(nd_desc, nvdimm, cmd, buf, buf_len, &cmd_rc);
1187 	if (rc < 0)
1188 		goto out_unlock;
1189 
1190 	if (!nvdimm && cmd == ND_CMD_CLEAR_ERROR && cmd_rc >= 0) {
1191 		struct nd_cmd_clear_error *clear_err = buf;
1192 
1193 		nvdimm_account_cleared_poison(nvdimm_bus, clear_err->address,
1194 				clear_err->cleared);
1195 	}
1196 
1197 	if (copy_to_user(p, buf, buf_len))
1198 		rc = -EFAULT;
1199 
1200 out_unlock:
1201 	nvdimm_bus_unlock(dev);
1202 	device_unlock(dev);
1203 out:
1204 	kfree(in_env);
1205 	kfree(out_env);
1206 	vfree(buf);
1207 	return rc;
1208 }
1209 
1210 enum nd_ioctl_mode {
1211 	BUS_IOCTL,
1212 	DIMM_IOCTL,
1213 };
1214 
1215 static int match_dimm(struct device *dev, void *data)
1216 {
1217 	long id = (long) data;
1218 
1219 	if (is_nvdimm(dev)) {
1220 		struct nvdimm *nvdimm = to_nvdimm(dev);
1221 
1222 		return nvdimm->id == id;
1223 	}
1224 
1225 	return 0;
1226 }
1227 
1228 static long nd_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
1229 		enum nd_ioctl_mode mode)
1230 
1231 {
1232 	struct nvdimm_bus *nvdimm_bus, *found = NULL;
1233 	long id = (long) file->private_data;
1234 	struct nvdimm *nvdimm = NULL;
1235 	int rc, ro;
1236 
1237 	ro = ((file->f_flags & O_ACCMODE) == O_RDONLY);
1238 	mutex_lock(&nvdimm_bus_list_mutex);
1239 	list_for_each_entry(nvdimm_bus, &nvdimm_bus_list, list) {
1240 		if (mode == DIMM_IOCTL) {
1241 			struct device *dev;
1242 
1243 			dev = device_find_child(&nvdimm_bus->dev,
1244 					file->private_data, match_dimm);
1245 			if (!dev)
1246 				continue;
1247 			nvdimm = to_nvdimm(dev);
1248 			found = nvdimm_bus;
1249 		} else if (nvdimm_bus->id == id) {
1250 			found = nvdimm_bus;
1251 		}
1252 
1253 		if (found) {
1254 			atomic_inc(&nvdimm_bus->ioctl_active);
1255 			break;
1256 		}
1257 	}
1258 	mutex_unlock(&nvdimm_bus_list_mutex);
1259 
1260 	if (!found)
1261 		return -ENXIO;
1262 
1263 	nvdimm_bus = found;
1264 	rc = __nd_ioctl(nvdimm_bus, nvdimm, ro, cmd, arg);
1265 
1266 	if (nvdimm)
1267 		put_device(&nvdimm->dev);
1268 	if (atomic_dec_and_test(&nvdimm_bus->ioctl_active))
1269 		wake_up(&nvdimm_bus->wait);
1270 
1271 	return rc;
1272 }
1273 
1274 static long bus_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1275 {
1276 	return nd_ioctl(file, cmd, arg, BUS_IOCTL);
1277 }
1278 
1279 static long dimm_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1280 {
1281 	return nd_ioctl(file, cmd, arg, DIMM_IOCTL);
1282 }
1283 
1284 static int nd_open(struct inode *inode, struct file *file)
1285 {
1286 	long minor = iminor(inode);
1287 
1288 	file->private_data = (void *) minor;
1289 	return 0;
1290 }
1291 
1292 static const struct file_operations nvdimm_bus_fops = {
1293 	.owner = THIS_MODULE,
1294 	.open = nd_open,
1295 	.unlocked_ioctl = bus_ioctl,
1296 	.compat_ioctl = compat_ptr_ioctl,
1297 	.llseek = noop_llseek,
1298 };
1299 
1300 static const struct file_operations nvdimm_fops = {
1301 	.owner = THIS_MODULE,
1302 	.open = nd_open,
1303 	.unlocked_ioctl = dimm_ioctl,
1304 	.compat_ioctl = compat_ptr_ioctl,
1305 	.llseek = noop_llseek,
1306 };
1307 
1308 int __init nvdimm_bus_init(void)
1309 {
1310 	int rc;
1311 
1312 	rc = bus_register(&nvdimm_bus_type);
1313 	if (rc)
1314 		return rc;
1315 
1316 	rc = register_chrdev(0, "ndctl", &nvdimm_bus_fops);
1317 	if (rc < 0)
1318 		goto err_bus_chrdev;
1319 	nvdimm_bus_major = rc;
1320 
1321 	rc = register_chrdev(0, "dimmctl", &nvdimm_fops);
1322 	if (rc < 0)
1323 		goto err_dimm_chrdev;
1324 	nvdimm_major = rc;
1325 
1326 	rc = class_register(&nd_class);
1327 	if (rc)
1328 		goto err_class;
1329 
1330 	rc = driver_register(&nd_bus_driver.drv);
1331 	if (rc)
1332 		goto err_nd_bus;
1333 
1334 	return 0;
1335 
1336  err_nd_bus:
1337 	class_unregister(&nd_class);
1338  err_class:
1339 	unregister_chrdev(nvdimm_major, "dimmctl");
1340  err_dimm_chrdev:
1341 	unregister_chrdev(nvdimm_bus_major, "ndctl");
1342  err_bus_chrdev:
1343 	bus_unregister(&nvdimm_bus_type);
1344 
1345 	return rc;
1346 }
1347 
1348 void nvdimm_bus_exit(void)
1349 {
1350 	driver_unregister(&nd_bus_driver.drv);
1351 	class_unregister(&nd_class);
1352 	unregister_chrdev(nvdimm_bus_major, "ndctl");
1353 	unregister_chrdev(nvdimm_major, "dimmctl");
1354 	bus_unregister(&nvdimm_bus_type);
1355 	ida_destroy(&nd_ida);
1356 }
1357