xref: /linux/drivers/nvdimm/bus.c (revision e7c22eeaff8565d9a8374f320238c251ca31480b)
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/genhd.h>
15 #include <linux/ndctl.h>
16 #include <linux/sched.h>
17 #include <linux/slab.h>
18 #include <linux/cpu.h>
19 #include <linux/fs.h>
20 #include <linux/io.h>
21 #include <linux/mm.h>
22 #include <linux/nd.h>
23 #include "nd-core.h"
24 #include "nd.h"
25 #include "pfn.h"
26 
27 int nvdimm_major;
28 static int nvdimm_bus_major;
29 struct class *nd_class;
30 static DEFINE_IDA(nd_ida);
31 
32 static int to_nd_device_type(struct device *dev)
33 {
34 	if (is_nvdimm(dev))
35 		return ND_DEVICE_DIMM;
36 	else if (is_memory(dev))
37 		return ND_DEVICE_REGION_PMEM;
38 	else if (is_nd_blk(dev))
39 		return ND_DEVICE_REGION_BLK;
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(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 	debug_nvdimm_lock(dev);
95 	rc = nd_drv->probe(dev);
96 	debug_nvdimm_unlock(dev);
97 
98 	if ((rc == 0 || rc == -EOPNOTSUPP) &&
99 			dev->parent && is_nd_region(dev->parent))
100 		nd_region_advance_seeds(to_nd_region(dev->parent), dev);
101 	nvdimm_bus_probe_end(nvdimm_bus);
102 
103 	dev_dbg(&nvdimm_bus->dev, "END: %s.probe(%s) = %d\n", dev->driver->name,
104 			dev_name(dev), rc);
105 
106 	if (rc != 0)
107 		module_put(provider);
108 	return rc;
109 }
110 
111 static int nvdimm_bus_remove(struct device *dev)
112 {
113 	struct nd_device_driver *nd_drv = to_nd_device_driver(dev->driver);
114 	struct module *provider = to_bus_provider(dev);
115 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
116 	int rc = 0;
117 
118 	if (nd_drv->remove) {
119 		debug_nvdimm_lock(dev);
120 		rc = nd_drv->remove(dev);
121 		debug_nvdimm_unlock(dev);
122 	}
123 
124 	dev_dbg(&nvdimm_bus->dev, "%s.remove(%s) = %d\n", dev->driver->name,
125 			dev_name(dev), rc);
126 	module_put(provider);
127 	return rc;
128 }
129 
130 static void nvdimm_bus_shutdown(struct device *dev)
131 {
132 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
133 	struct nd_device_driver *nd_drv = NULL;
134 
135 	if (dev->driver)
136 		nd_drv = to_nd_device_driver(dev->driver);
137 
138 	if (nd_drv && nd_drv->shutdown) {
139 		nd_drv->shutdown(dev);
140 		dev_dbg(&nvdimm_bus->dev, "%s.shutdown(%s)\n",
141 				dev->driver->name, dev_name(dev));
142 	}
143 }
144 
145 void nd_device_notify(struct device *dev, enum nvdimm_event event)
146 {
147 	nd_device_lock(dev);
148 	if (dev->driver) {
149 		struct nd_device_driver *nd_drv;
150 
151 		nd_drv = to_nd_device_driver(dev->driver);
152 		if (nd_drv->notify)
153 			nd_drv->notify(dev, event);
154 	}
155 	nd_device_unlock(dev);
156 }
157 EXPORT_SYMBOL(nd_device_notify);
158 
159 void nvdimm_region_notify(struct nd_region *nd_region, enum nvdimm_event event)
160 {
161 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&nd_region->dev);
162 
163 	if (!nvdimm_bus)
164 		return;
165 
166 	/* caller is responsible for holding a reference on the device */
167 	nd_device_notify(&nd_region->dev, event);
168 }
169 EXPORT_SYMBOL_GPL(nvdimm_region_notify);
170 
171 struct clear_badblocks_context {
172 	resource_size_t phys, cleared;
173 };
174 
175 static int nvdimm_clear_badblocks_region(struct device *dev, void *data)
176 {
177 	struct clear_badblocks_context *ctx = data;
178 	struct nd_region *nd_region;
179 	resource_size_t ndr_end;
180 	sector_t sector;
181 
182 	/* make sure device is a region */
183 	if (!is_memory(dev))
184 		return 0;
185 
186 	nd_region = to_nd_region(dev);
187 	ndr_end = nd_region->ndr_start + nd_region->ndr_size - 1;
188 
189 	/* make sure we are in the region */
190 	if (ctx->phys < nd_region->ndr_start
191 			|| (ctx->phys + ctx->cleared) > ndr_end)
192 		return 0;
193 
194 	sector = (ctx->phys - nd_region->ndr_start) / 512;
195 	badblocks_clear(&nd_region->bb, sector, ctx->cleared / 512);
196 
197 	if (nd_region->bb_state)
198 		sysfs_notify_dirent(nd_region->bb_state);
199 
200 	return 0;
201 }
202 
203 static void nvdimm_clear_badblocks_regions(struct nvdimm_bus *nvdimm_bus,
204 		phys_addr_t phys, u64 cleared)
205 {
206 	struct clear_badblocks_context ctx = {
207 		.phys = phys,
208 		.cleared = cleared,
209 	};
210 
211 	device_for_each_child(&nvdimm_bus->dev, &ctx,
212 			nvdimm_clear_badblocks_region);
213 }
214 
215 static void nvdimm_account_cleared_poison(struct nvdimm_bus *nvdimm_bus,
216 		phys_addr_t phys, u64 cleared)
217 {
218 	if (cleared > 0)
219 		badrange_forget(&nvdimm_bus->badrange, phys, cleared);
220 
221 	if (cleared > 0 && cleared / 512)
222 		nvdimm_clear_badblocks_regions(nvdimm_bus, phys, cleared);
223 }
224 
225 long nvdimm_clear_poison(struct device *dev, phys_addr_t phys,
226 		unsigned int len)
227 {
228 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
229 	struct nvdimm_bus_descriptor *nd_desc;
230 	struct nd_cmd_clear_error clear_err;
231 	struct nd_cmd_ars_cap ars_cap;
232 	u32 clear_err_unit, mask;
233 	unsigned int noio_flag;
234 	int cmd_rc, rc;
235 
236 	if (!nvdimm_bus)
237 		return -ENXIO;
238 
239 	nd_desc = nvdimm_bus->nd_desc;
240 	/*
241 	 * if ndctl does not exist, it's PMEM_LEGACY and
242 	 * we want to just pretend everything is handled.
243 	 */
244 	if (!nd_desc->ndctl)
245 		return len;
246 
247 	memset(&ars_cap, 0, sizeof(ars_cap));
248 	ars_cap.address = phys;
249 	ars_cap.length = len;
250 	noio_flag = memalloc_noio_save();
251 	rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_ARS_CAP, &ars_cap,
252 			sizeof(ars_cap), &cmd_rc);
253 	memalloc_noio_restore(noio_flag);
254 	if (rc < 0)
255 		return rc;
256 	if (cmd_rc < 0)
257 		return cmd_rc;
258 	clear_err_unit = ars_cap.clear_err_unit;
259 	if (!clear_err_unit || !is_power_of_2(clear_err_unit))
260 		return -ENXIO;
261 
262 	mask = clear_err_unit - 1;
263 	if ((phys | len) & mask)
264 		return -ENXIO;
265 	memset(&clear_err, 0, sizeof(clear_err));
266 	clear_err.address = phys;
267 	clear_err.length = len;
268 	noio_flag = memalloc_noio_save();
269 	rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_CLEAR_ERROR, &clear_err,
270 			sizeof(clear_err), &cmd_rc);
271 	memalloc_noio_restore(noio_flag);
272 	if (rc < 0)
273 		return rc;
274 	if (cmd_rc < 0)
275 		return cmd_rc;
276 
277 	nvdimm_account_cleared_poison(nvdimm_bus, phys, clear_err.cleared);
278 
279 	return clear_err.cleared;
280 }
281 EXPORT_SYMBOL_GPL(nvdimm_clear_poison);
282 
283 static int nvdimm_bus_match(struct device *dev, struct device_driver *drv);
284 
285 static struct bus_type nvdimm_bus_type = {
286 	.name = "nd",
287 	.uevent = nvdimm_bus_uevent,
288 	.match = nvdimm_bus_match,
289 	.probe = nvdimm_bus_probe,
290 	.remove = nvdimm_bus_remove,
291 	.shutdown = nvdimm_bus_shutdown,
292 };
293 
294 static void nvdimm_bus_release(struct device *dev)
295 {
296 	struct nvdimm_bus *nvdimm_bus;
297 
298 	nvdimm_bus = container_of(dev, struct nvdimm_bus, dev);
299 	ida_simple_remove(&nd_ida, nvdimm_bus->id);
300 	kfree(nvdimm_bus);
301 }
302 
303 static const struct device_type nvdimm_bus_dev_type = {
304 	.release = nvdimm_bus_release,
305 	.groups = nvdimm_bus_attribute_groups,
306 };
307 
308 bool is_nvdimm_bus(struct device *dev)
309 {
310 	return dev->type == &nvdimm_bus_dev_type;
311 }
312 
313 struct nvdimm_bus *walk_to_nvdimm_bus(struct device *nd_dev)
314 {
315 	struct device *dev;
316 
317 	for (dev = nd_dev; dev; dev = dev->parent)
318 		if (is_nvdimm_bus(dev))
319 			break;
320 	dev_WARN_ONCE(nd_dev, !dev, "invalid dev, not on nd bus\n");
321 	if (dev)
322 		return to_nvdimm_bus(dev);
323 	return NULL;
324 }
325 
326 struct nvdimm_bus *to_nvdimm_bus(struct device *dev)
327 {
328 	struct nvdimm_bus *nvdimm_bus;
329 
330 	nvdimm_bus = container_of(dev, struct nvdimm_bus, dev);
331 	WARN_ON(!is_nvdimm_bus(dev));
332 	return nvdimm_bus;
333 }
334 EXPORT_SYMBOL_GPL(to_nvdimm_bus);
335 
336 struct nvdimm_bus *nvdimm_to_bus(struct nvdimm *nvdimm)
337 {
338 	return to_nvdimm_bus(nvdimm->dev.parent);
339 }
340 EXPORT_SYMBOL_GPL(nvdimm_to_bus);
341 
342 struct nvdimm_bus *nvdimm_bus_register(struct device *parent,
343 		struct nvdimm_bus_descriptor *nd_desc)
344 {
345 	struct nvdimm_bus *nvdimm_bus;
346 	int rc;
347 
348 	nvdimm_bus = kzalloc(sizeof(*nvdimm_bus), GFP_KERNEL);
349 	if (!nvdimm_bus)
350 		return NULL;
351 	INIT_LIST_HEAD(&nvdimm_bus->list);
352 	INIT_LIST_HEAD(&nvdimm_bus->mapping_list);
353 	init_waitqueue_head(&nvdimm_bus->wait);
354 	nvdimm_bus->id = ida_simple_get(&nd_ida, 0, 0, GFP_KERNEL);
355 	if (nvdimm_bus->id < 0) {
356 		kfree(nvdimm_bus);
357 		return NULL;
358 	}
359 	mutex_init(&nvdimm_bus->reconfig_mutex);
360 	badrange_init(&nvdimm_bus->badrange);
361 	nvdimm_bus->nd_desc = nd_desc;
362 	nvdimm_bus->dev.parent = parent;
363 	nvdimm_bus->dev.type = &nvdimm_bus_dev_type;
364 	nvdimm_bus->dev.groups = nd_desc->attr_groups;
365 	nvdimm_bus->dev.bus = &nvdimm_bus_type;
366 	nvdimm_bus->dev.of_node = nd_desc->of_node;
367 	dev_set_name(&nvdimm_bus->dev, "ndbus%d", nvdimm_bus->id);
368 	rc = device_register(&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 		struct nvdimm *nvdimm = to_nvdimm(dev);
402 		bool dev_put = false;
403 
404 		/* We are shutting down. Make state frozen artificially. */
405 		nvdimm_bus_lock(dev);
406 		set_bit(NVDIMM_SECURITY_FROZEN, &nvdimm->sec.flags);
407 		if (test_and_clear_bit(NDD_WORK_PENDING, &nvdimm->flags))
408 			dev_put = true;
409 		nvdimm_bus_unlock(dev);
410 		cancel_delayed_work_sync(&nvdimm->dwork);
411 		if (dev_put)
412 			put_device(dev);
413 	}
414 	nd_device_unregister(dev, ND_SYNC);
415 
416 	return 0;
417 }
418 
419 static void free_badrange_list(struct list_head *badrange_list)
420 {
421 	struct badrange_entry *bre, *next;
422 
423 	list_for_each_entry_safe(bre, next, badrange_list, list) {
424 		list_del(&bre->list);
425 		kfree(bre);
426 	}
427 	list_del_init(badrange_list);
428 }
429 
430 static int nd_bus_remove(struct device *dev)
431 {
432 	struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
433 
434 	mutex_lock(&nvdimm_bus_list_mutex);
435 	list_del_init(&nvdimm_bus->list);
436 	mutex_unlock(&nvdimm_bus_list_mutex);
437 
438 	wait_event(nvdimm_bus->wait,
439 			atomic_read(&nvdimm_bus->ioctl_active) == 0);
440 
441 	nd_synchronize();
442 	device_for_each_child(&nvdimm_bus->dev, NULL, child_unregister);
443 
444 	spin_lock(&nvdimm_bus->badrange.lock);
445 	free_badrange_list(&nvdimm_bus->badrange.list);
446 	spin_unlock(&nvdimm_bus->badrange.lock);
447 
448 	nvdimm_bus_destroy_ndctl(nvdimm_bus);
449 
450 	return 0;
451 }
452 
453 static int nd_bus_probe(struct device *dev)
454 {
455 	struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
456 	int rc;
457 
458 	rc = nvdimm_bus_create_ndctl(nvdimm_bus);
459 	if (rc)
460 		return rc;
461 
462 	mutex_lock(&nvdimm_bus_list_mutex);
463 	list_add_tail(&nvdimm_bus->list, &nvdimm_bus_list);
464 	mutex_unlock(&nvdimm_bus_list_mutex);
465 
466 	/* enable bus provider attributes to look up their local context */
467 	dev_set_drvdata(dev, nvdimm_bus->nd_desc);
468 
469 	return 0;
470 }
471 
472 static struct nd_device_driver nd_bus_driver = {
473 	.probe = nd_bus_probe,
474 	.remove = nd_bus_remove,
475 	.drv = {
476 		.name = "nd_bus",
477 		.suppress_bind_attrs = true,
478 		.bus = &nvdimm_bus_type,
479 		.owner = THIS_MODULE,
480 		.mod_name = KBUILD_MODNAME,
481 	},
482 };
483 
484 static int nvdimm_bus_match(struct device *dev, struct device_driver *drv)
485 {
486 	struct nd_device_driver *nd_drv = to_nd_device_driver(drv);
487 
488 	if (is_nvdimm_bus(dev) && nd_drv == &nd_bus_driver)
489 		return true;
490 
491 	return !!test_bit(to_nd_device_type(dev), &nd_drv->type);
492 }
493 
494 static ASYNC_DOMAIN_EXCLUSIVE(nd_async_domain);
495 
496 void nd_synchronize(void)
497 {
498 	async_synchronize_full_domain(&nd_async_domain);
499 }
500 EXPORT_SYMBOL_GPL(nd_synchronize);
501 
502 static void nd_async_device_register(void *d, async_cookie_t cookie)
503 {
504 	struct device *dev = d;
505 
506 	if (device_add(dev) != 0) {
507 		dev_err(dev, "%s: failed\n", __func__);
508 		put_device(dev);
509 	}
510 	put_device(dev);
511 	if (dev->parent)
512 		put_device(dev->parent);
513 }
514 
515 static void nd_async_device_unregister(void *d, async_cookie_t cookie)
516 {
517 	struct device *dev = d;
518 
519 	/* flush bus operations before delete */
520 	nvdimm_bus_lock(dev);
521 	nvdimm_bus_unlock(dev);
522 
523 	device_unregister(dev);
524 	put_device(dev);
525 }
526 
527 void __nd_device_register(struct device *dev)
528 {
529 	if (!dev)
530 		return;
531 
532 	/*
533 	 * Ensure that region devices always have their NUMA node set as
534 	 * early as possible. This way we are able to make certain that
535 	 * any memory associated with the creation and the creation
536 	 * itself of the region is associated with the correct node.
537 	 */
538 	if (is_nd_region(dev))
539 		set_dev_node(dev, to_nd_region(dev)->numa_node);
540 
541 	dev->bus = &nvdimm_bus_type;
542 	if (dev->parent) {
543 		get_device(dev->parent);
544 		if (dev_to_node(dev) == NUMA_NO_NODE)
545 			set_dev_node(dev, dev_to_node(dev->parent));
546 	}
547 	get_device(dev);
548 
549 	async_schedule_dev_domain(nd_async_device_register, dev,
550 				  &nd_async_domain);
551 }
552 
553 void nd_device_register(struct device *dev)
554 {
555 	device_initialize(dev);
556 	__nd_device_register(dev);
557 }
558 EXPORT_SYMBOL(nd_device_register);
559 
560 void nd_device_unregister(struct device *dev, enum nd_async_mode mode)
561 {
562 	bool killed;
563 
564 	switch (mode) {
565 	case ND_ASYNC:
566 		/*
567 		 * In the async case this is being triggered with the
568 		 * device lock held and the unregistration work needs to
569 		 * be moved out of line iff this is thread has won the
570 		 * race to schedule the deletion.
571 		 */
572 		if (!kill_device(dev))
573 			return;
574 
575 		get_device(dev);
576 		async_schedule_domain(nd_async_device_unregister, dev,
577 				&nd_async_domain);
578 		break;
579 	case ND_SYNC:
580 		/*
581 		 * In the sync case the device is being unregistered due
582 		 * to a state change of the parent. Claim the kill state
583 		 * to synchronize against other unregistration requests,
584 		 * or otherwise let the async path handle it if the
585 		 * unregistration was already queued.
586 		 */
587 		nd_device_lock(dev);
588 		killed = kill_device(dev);
589 		nd_device_unlock(dev);
590 
591 		if (!killed)
592 			return;
593 
594 		nd_synchronize();
595 		device_unregister(dev);
596 		break;
597 	}
598 }
599 EXPORT_SYMBOL(nd_device_unregister);
600 
601 /**
602  * __nd_driver_register() - register a region or a namespace driver
603  * @nd_drv: driver to register
604  * @owner: automatically set by nd_driver_register() macro
605  * @mod_name: automatically set by nd_driver_register() macro
606  */
607 int __nd_driver_register(struct nd_device_driver *nd_drv, struct module *owner,
608 		const char *mod_name)
609 {
610 	struct device_driver *drv = &nd_drv->drv;
611 
612 	if (!nd_drv->type) {
613 		pr_debug("driver type bitmask not set (%ps)\n",
614 				__builtin_return_address(0));
615 		return -EINVAL;
616 	}
617 
618 	if (!nd_drv->probe) {
619 		pr_debug("%s ->probe() must be specified\n", mod_name);
620 		return -EINVAL;
621 	}
622 
623 	drv->bus = &nvdimm_bus_type;
624 	drv->owner = owner;
625 	drv->mod_name = mod_name;
626 
627 	return driver_register(drv);
628 }
629 EXPORT_SYMBOL(__nd_driver_register);
630 
631 void nvdimm_check_and_set_ro(struct gendisk *disk)
632 {
633 	struct device *dev = disk_to_dev(disk)->parent;
634 	struct nd_region *nd_region = to_nd_region(dev->parent);
635 	int disk_ro = get_disk_ro(disk);
636 
637 	/*
638 	 * Upgrade to read-only if the region is read-only preserve as
639 	 * read-only if the disk is already read-only.
640 	 */
641 	if (disk_ro || nd_region->ro == disk_ro)
642 		return;
643 
644 	dev_info(dev, "%s read-only, marking %s read-only\n",
645 			dev_name(&nd_region->dev), disk->disk_name);
646 	set_disk_ro(disk, 1);
647 }
648 EXPORT_SYMBOL(nvdimm_check_and_set_ro);
649 
650 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
651 		char *buf)
652 {
653 	return sprintf(buf, ND_DEVICE_MODALIAS_FMT "\n",
654 			to_nd_device_type(dev));
655 }
656 static DEVICE_ATTR_RO(modalias);
657 
658 static ssize_t devtype_show(struct device *dev, struct device_attribute *attr,
659 		char *buf)
660 {
661 	return sprintf(buf, "%s\n", dev->type->name);
662 }
663 static DEVICE_ATTR_RO(devtype);
664 
665 static struct attribute *nd_device_attributes[] = {
666 	&dev_attr_modalias.attr,
667 	&dev_attr_devtype.attr,
668 	NULL,
669 };
670 
671 /*
672  * nd_device_attribute_group - generic attributes for all devices on an nd bus
673  */
674 const struct attribute_group nd_device_attribute_group = {
675 	.attrs = nd_device_attributes,
676 };
677 
678 static ssize_t numa_node_show(struct device *dev,
679 		struct device_attribute *attr, char *buf)
680 {
681 	return sprintf(buf, "%d\n", dev_to_node(dev));
682 }
683 static DEVICE_ATTR_RO(numa_node);
684 
685 static int nvdimm_dev_to_target_node(struct device *dev)
686 {
687 	struct device *parent = dev->parent;
688 	struct nd_region *nd_region = NULL;
689 
690 	if (is_nd_region(dev))
691 		nd_region = to_nd_region(dev);
692 	else if (parent && is_nd_region(parent))
693 		nd_region = to_nd_region(parent);
694 
695 	if (!nd_region)
696 		return NUMA_NO_NODE;
697 	return nd_region->target_node;
698 }
699 
700 static ssize_t target_node_show(struct device *dev,
701 		struct device_attribute *attr, char *buf)
702 {
703 	return sprintf(buf, "%d\n", nvdimm_dev_to_target_node(dev));
704 }
705 static DEVICE_ATTR_RO(target_node);
706 
707 static struct attribute *nd_numa_attributes[] = {
708 	&dev_attr_numa_node.attr,
709 	&dev_attr_target_node.attr,
710 	NULL,
711 };
712 
713 static umode_t nd_numa_attr_visible(struct kobject *kobj, struct attribute *a,
714 		int n)
715 {
716 	struct device *dev = container_of(kobj, typeof(*dev), kobj);
717 
718 	if (!IS_ENABLED(CONFIG_NUMA))
719 		return 0;
720 
721 	if (a == &dev_attr_target_node.attr &&
722 			nvdimm_dev_to_target_node(dev) == NUMA_NO_NODE)
723 		return 0;
724 
725 	return a->mode;
726 }
727 
728 /*
729  * nd_numa_attribute_group - NUMA attributes for all devices on an nd bus
730  */
731 const struct attribute_group nd_numa_attribute_group = {
732 	.attrs = nd_numa_attributes,
733 	.is_visible = nd_numa_attr_visible,
734 };
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 
741 	dev = device_create(nd_class, &nvdimm_bus->dev, devt, nvdimm_bus,
742 			"ndctl%d", nvdimm_bus->id);
743 
744 	if (IS_ERR(dev))
745 		dev_dbg(&nvdimm_bus->dev, "failed to register ndctl%d: %ld\n",
746 				nvdimm_bus->id, PTR_ERR(dev));
747 	return PTR_ERR_OR_ZERO(dev);
748 }
749 
750 void nvdimm_bus_destroy_ndctl(struct nvdimm_bus *nvdimm_bus)
751 {
752 	device_destroy(nd_class, MKDEV(nvdimm_bus_major, nvdimm_bus->id));
753 }
754 
755 static const struct nd_cmd_desc __nd_cmd_dimm_descs[] = {
756 	[ND_CMD_IMPLEMENTED] = { },
757 	[ND_CMD_SMART] = {
758 		.out_num = 2,
759 		.out_sizes = { 4, 128, },
760 	},
761 	[ND_CMD_SMART_THRESHOLD] = {
762 		.out_num = 2,
763 		.out_sizes = { 4, 8, },
764 	},
765 	[ND_CMD_DIMM_FLAGS] = {
766 		.out_num = 2,
767 		.out_sizes = { 4, 4 },
768 	},
769 	[ND_CMD_GET_CONFIG_SIZE] = {
770 		.out_num = 3,
771 		.out_sizes = { 4, 4, 4, },
772 	},
773 	[ND_CMD_GET_CONFIG_DATA] = {
774 		.in_num = 2,
775 		.in_sizes = { 4, 4, },
776 		.out_num = 2,
777 		.out_sizes = { 4, UINT_MAX, },
778 	},
779 	[ND_CMD_SET_CONFIG_DATA] = {
780 		.in_num = 3,
781 		.in_sizes = { 4, 4, UINT_MAX, },
782 		.out_num = 1,
783 		.out_sizes = { 4, },
784 	},
785 	[ND_CMD_VENDOR] = {
786 		.in_num = 3,
787 		.in_sizes = { 4, 4, UINT_MAX, },
788 		.out_num = 3,
789 		.out_sizes = { 4, 4, UINT_MAX, },
790 	},
791 	[ND_CMD_CALL] = {
792 		.in_num = 2,
793 		.in_sizes = { sizeof(struct nd_cmd_pkg), UINT_MAX, },
794 		.out_num = 1,
795 		.out_sizes = { UINT_MAX, },
796 	},
797 };
798 
799 const struct nd_cmd_desc *nd_cmd_dimm_desc(int cmd)
800 {
801 	if (cmd < ARRAY_SIZE(__nd_cmd_dimm_descs))
802 		return &__nd_cmd_dimm_descs[cmd];
803 	return NULL;
804 }
805 EXPORT_SYMBOL_GPL(nd_cmd_dimm_desc);
806 
807 static const struct nd_cmd_desc __nd_cmd_bus_descs[] = {
808 	[ND_CMD_IMPLEMENTED] = { },
809 	[ND_CMD_ARS_CAP] = {
810 		.in_num = 2,
811 		.in_sizes = { 8, 8, },
812 		.out_num = 4,
813 		.out_sizes = { 4, 4, 4, 4, },
814 	},
815 	[ND_CMD_ARS_START] = {
816 		.in_num = 5,
817 		.in_sizes = { 8, 8, 2, 1, 5, },
818 		.out_num = 2,
819 		.out_sizes = { 4, 4, },
820 	},
821 	[ND_CMD_ARS_STATUS] = {
822 		.out_num = 3,
823 		.out_sizes = { 4, 4, UINT_MAX, },
824 	},
825 	[ND_CMD_CLEAR_ERROR] = {
826 		.in_num = 2,
827 		.in_sizes = { 8, 8, },
828 		.out_num = 3,
829 		.out_sizes = { 4, 4, 8, },
830 	},
831 	[ND_CMD_CALL] = {
832 		.in_num = 2,
833 		.in_sizes = { sizeof(struct nd_cmd_pkg), UINT_MAX, },
834 		.out_num = 1,
835 		.out_sizes = { UINT_MAX, },
836 	},
837 };
838 
839 const struct nd_cmd_desc *nd_cmd_bus_desc(int cmd)
840 {
841 	if (cmd < ARRAY_SIZE(__nd_cmd_bus_descs))
842 		return &__nd_cmd_bus_descs[cmd];
843 	return NULL;
844 }
845 EXPORT_SYMBOL_GPL(nd_cmd_bus_desc);
846 
847 u32 nd_cmd_in_size(struct nvdimm *nvdimm, int cmd,
848 		const struct nd_cmd_desc *desc, int idx, void *buf)
849 {
850 	if (idx >= desc->in_num)
851 		return UINT_MAX;
852 
853 	if (desc->in_sizes[idx] < UINT_MAX)
854 		return desc->in_sizes[idx];
855 
856 	if (nvdimm && cmd == ND_CMD_SET_CONFIG_DATA && idx == 2) {
857 		struct nd_cmd_set_config_hdr *hdr = buf;
858 
859 		return hdr->in_length;
860 	} else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2) {
861 		struct nd_cmd_vendor_hdr *hdr = buf;
862 
863 		return hdr->in_length;
864 	} else if (cmd == ND_CMD_CALL) {
865 		struct nd_cmd_pkg *pkg = buf;
866 
867 		return pkg->nd_size_in;
868 	}
869 
870 	return UINT_MAX;
871 }
872 EXPORT_SYMBOL_GPL(nd_cmd_in_size);
873 
874 u32 nd_cmd_out_size(struct nvdimm *nvdimm, int cmd,
875 		const struct nd_cmd_desc *desc, int idx, const u32 *in_field,
876 		const u32 *out_field, unsigned long remainder)
877 {
878 	if (idx >= desc->out_num)
879 		return UINT_MAX;
880 
881 	if (desc->out_sizes[idx] < UINT_MAX)
882 		return desc->out_sizes[idx];
883 
884 	if (nvdimm && cmd == ND_CMD_GET_CONFIG_DATA && idx == 1)
885 		return in_field[1];
886 	else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2)
887 		return out_field[1];
888 	else if (!nvdimm && cmd == ND_CMD_ARS_STATUS && idx == 2) {
889 		/*
890 		 * Per table 9-276 ARS Data in ACPI 6.1, out_field[1] is
891 		 * "Size of Output Buffer in bytes, including this
892 		 * field."
893 		 */
894 		if (out_field[1] < 4)
895 			return 0;
896 		/*
897 		 * ACPI 6.1 is ambiguous if 'status' is included in the
898 		 * output size. If we encounter an output size that
899 		 * overshoots the remainder by 4 bytes, assume it was
900 		 * including 'status'.
901 		 */
902 		if (out_field[1] - 4 == remainder)
903 			return remainder;
904 		return out_field[1] - 8;
905 	} else if (cmd == ND_CMD_CALL) {
906 		struct nd_cmd_pkg *pkg = (struct nd_cmd_pkg *) in_field;
907 
908 		return pkg->nd_size_out;
909 	}
910 
911 
912 	return UINT_MAX;
913 }
914 EXPORT_SYMBOL_GPL(nd_cmd_out_size);
915 
916 void wait_nvdimm_bus_probe_idle(struct device *dev)
917 {
918 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
919 
920 	do {
921 		if (nvdimm_bus->probe_active == 0)
922 			break;
923 		nvdimm_bus_unlock(dev);
924 		nd_device_unlock(dev);
925 		wait_event(nvdimm_bus->wait,
926 				nvdimm_bus->probe_active == 0);
927 		nd_device_lock(dev);
928 		nvdimm_bus_lock(dev);
929 	} while (true);
930 }
931 
932 static int nd_pmem_forget_poison_check(struct device *dev, void *data)
933 {
934 	struct nd_cmd_clear_error *clear_err =
935 		(struct nd_cmd_clear_error *)data;
936 	struct nd_btt *nd_btt = is_nd_btt(dev) ? to_nd_btt(dev) : NULL;
937 	struct nd_pfn *nd_pfn = is_nd_pfn(dev) ? to_nd_pfn(dev) : NULL;
938 	struct nd_dax *nd_dax = is_nd_dax(dev) ? to_nd_dax(dev) : NULL;
939 	struct nd_namespace_common *ndns = NULL;
940 	struct nd_namespace_io *nsio;
941 	resource_size_t offset = 0, end_trunc = 0, start, end, pstart, pend;
942 
943 	if (nd_dax || !dev->driver)
944 		return 0;
945 
946 	start = clear_err->address;
947 	end = clear_err->address + clear_err->cleared - 1;
948 
949 	if (nd_btt || nd_pfn || nd_dax) {
950 		if (nd_btt)
951 			ndns = nd_btt->ndns;
952 		else if (nd_pfn)
953 			ndns = nd_pfn->ndns;
954 		else if (nd_dax)
955 			ndns = nd_dax->nd_pfn.ndns;
956 
957 		if (!ndns)
958 			return 0;
959 	} else
960 		ndns = to_ndns(dev);
961 
962 	nsio = to_nd_namespace_io(&ndns->dev);
963 	pstart = nsio->res.start + offset;
964 	pend = nsio->res.end - end_trunc;
965 
966 	if ((pstart >= start) && (pend <= end))
967 		return -EBUSY;
968 
969 	return 0;
970 
971 }
972 
973 static int nd_ns_forget_poison_check(struct device *dev, void *data)
974 {
975 	return device_for_each_child(dev, data, nd_pmem_forget_poison_check);
976 }
977 
978 /* set_config requires an idle interleave set */
979 static int nd_cmd_clear_to_send(struct nvdimm_bus *nvdimm_bus,
980 		struct nvdimm *nvdimm, unsigned int cmd, void *data)
981 {
982 	struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
983 
984 	/* ask the bus provider if it would like to block this request */
985 	if (nd_desc->clear_to_send) {
986 		int rc = nd_desc->clear_to_send(nd_desc, nvdimm, cmd, data);
987 
988 		if (rc)
989 			return rc;
990 	}
991 
992 	/* require clear error to go through the pmem driver */
993 	if (!nvdimm && cmd == ND_CMD_CLEAR_ERROR)
994 		return device_for_each_child(&nvdimm_bus->dev, data,
995 				nd_ns_forget_poison_check);
996 
997 	if (!nvdimm || cmd != ND_CMD_SET_CONFIG_DATA)
998 		return 0;
999 
1000 	/* prevent label manipulation while the kernel owns label updates */
1001 	wait_nvdimm_bus_probe_idle(&nvdimm_bus->dev);
1002 	if (atomic_read(&nvdimm->busy))
1003 		return -EBUSY;
1004 	return 0;
1005 }
1006 
1007 static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm,
1008 		int read_only, unsigned int ioctl_cmd, unsigned long arg)
1009 {
1010 	struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
1011 	const struct nd_cmd_desc *desc = NULL;
1012 	unsigned int cmd = _IOC_NR(ioctl_cmd);
1013 	struct device *dev = &nvdimm_bus->dev;
1014 	void __user *p = (void __user *) arg;
1015 	char *out_env = NULL, *in_env = NULL;
1016 	const char *cmd_name, *dimm_name;
1017 	u32 in_len = 0, out_len = 0;
1018 	unsigned int func = cmd;
1019 	unsigned long cmd_mask;
1020 	struct nd_cmd_pkg pkg;
1021 	int rc, i, cmd_rc;
1022 	void *buf = NULL;
1023 	u64 buf_len = 0;
1024 
1025 	if (nvdimm) {
1026 		desc = nd_cmd_dimm_desc(cmd);
1027 		cmd_name = nvdimm_cmd_name(cmd);
1028 		cmd_mask = nvdimm->cmd_mask;
1029 		dimm_name = dev_name(&nvdimm->dev);
1030 	} else {
1031 		desc = nd_cmd_bus_desc(cmd);
1032 		cmd_name = nvdimm_bus_cmd_name(cmd);
1033 		cmd_mask = nd_desc->cmd_mask;
1034 		dimm_name = "bus";
1035 	}
1036 
1037 	/* Validate command family support against bus declared support */
1038 	if (cmd == ND_CMD_CALL) {
1039 		unsigned long *mask;
1040 
1041 		if (copy_from_user(&pkg, p, sizeof(pkg)))
1042 			return -EFAULT;
1043 
1044 		if (nvdimm) {
1045 			if (pkg.nd_family > NVDIMM_FAMILY_MAX)
1046 				return -EINVAL;
1047 			mask = &nd_desc->dimm_family_mask;
1048 		} else {
1049 			if (pkg.nd_family > NVDIMM_BUS_FAMILY_MAX)
1050 				return -EINVAL;
1051 			mask = &nd_desc->bus_family_mask;
1052 		}
1053 
1054 		if (!test_bit(pkg.nd_family, mask))
1055 			return -EINVAL;
1056 	}
1057 
1058 	if (!desc ||
1059 	    (desc->out_num + desc->in_num == 0) ||
1060 	    cmd > ND_CMD_CALL ||
1061 	    !test_bit(cmd, &cmd_mask))
1062 		return -ENOTTY;
1063 
1064 	/* fail write commands (when read-only) */
1065 	if (read_only)
1066 		switch (cmd) {
1067 		case ND_CMD_VENDOR:
1068 		case ND_CMD_SET_CONFIG_DATA:
1069 		case ND_CMD_ARS_START:
1070 		case ND_CMD_CLEAR_ERROR:
1071 		case ND_CMD_CALL:
1072 			dev_dbg(dev, "'%s' command while read-only.\n",
1073 					nvdimm ? nvdimm_cmd_name(cmd)
1074 					: nvdimm_bus_cmd_name(cmd));
1075 			return -EPERM;
1076 		default:
1077 			break;
1078 		}
1079 
1080 	/* process an input envelope */
1081 	in_env = kzalloc(ND_CMD_MAX_ENVELOPE, GFP_KERNEL);
1082 	if (!in_env)
1083 		return -ENOMEM;
1084 	for (i = 0; i < desc->in_num; i++) {
1085 		u32 in_size, copy;
1086 
1087 		in_size = nd_cmd_in_size(nvdimm, cmd, desc, i, in_env);
1088 		if (in_size == UINT_MAX) {
1089 			dev_err(dev, "%s:%s unknown input size cmd: %s field: %d\n",
1090 					__func__, dimm_name, cmd_name, i);
1091 			rc = -ENXIO;
1092 			goto out;
1093 		}
1094 		if (in_len < ND_CMD_MAX_ENVELOPE)
1095 			copy = min_t(u32, ND_CMD_MAX_ENVELOPE - in_len, in_size);
1096 		else
1097 			copy = 0;
1098 		if (copy && copy_from_user(&in_env[in_len], p + in_len, copy)) {
1099 			rc = -EFAULT;
1100 			goto out;
1101 		}
1102 		in_len += in_size;
1103 	}
1104 
1105 	if (cmd == ND_CMD_CALL) {
1106 		func = pkg.nd_command;
1107 		dev_dbg(dev, "%s, idx: %llu, in: %u, out: %u, len %llu\n",
1108 				dimm_name, pkg.nd_command,
1109 				in_len, out_len, buf_len);
1110 	}
1111 
1112 	/* process an output envelope */
1113 	out_env = kzalloc(ND_CMD_MAX_ENVELOPE, GFP_KERNEL);
1114 	if (!out_env) {
1115 		rc = -ENOMEM;
1116 		goto out;
1117 	}
1118 
1119 	for (i = 0; i < desc->out_num; i++) {
1120 		u32 out_size = nd_cmd_out_size(nvdimm, cmd, desc, i,
1121 				(u32 *) in_env, (u32 *) out_env, 0);
1122 		u32 copy;
1123 
1124 		if (out_size == UINT_MAX) {
1125 			dev_dbg(dev, "%s unknown output size cmd: %s field: %d\n",
1126 					dimm_name, cmd_name, i);
1127 			rc = -EFAULT;
1128 			goto out;
1129 		}
1130 		if (out_len < ND_CMD_MAX_ENVELOPE)
1131 			copy = min_t(u32, ND_CMD_MAX_ENVELOPE - out_len, out_size);
1132 		else
1133 			copy = 0;
1134 		if (copy && copy_from_user(&out_env[out_len],
1135 					p + in_len + out_len, copy)) {
1136 			rc = -EFAULT;
1137 			goto out;
1138 		}
1139 		out_len += out_size;
1140 	}
1141 
1142 	buf_len = (u64) out_len + (u64) in_len;
1143 	if (buf_len > ND_IOCTL_MAX_BUFLEN) {
1144 		dev_dbg(dev, "%s cmd: %s buf_len: %llu > %d\n", dimm_name,
1145 				cmd_name, buf_len, ND_IOCTL_MAX_BUFLEN);
1146 		rc = -EINVAL;
1147 		goto out;
1148 	}
1149 
1150 	buf = vmalloc(buf_len);
1151 	if (!buf) {
1152 		rc = -ENOMEM;
1153 		goto out;
1154 	}
1155 
1156 	if (copy_from_user(buf, p, buf_len)) {
1157 		rc = -EFAULT;
1158 		goto out;
1159 	}
1160 
1161 	nd_device_lock(dev);
1162 	nvdimm_bus_lock(dev);
1163 	rc = nd_cmd_clear_to_send(nvdimm_bus, nvdimm, func, buf);
1164 	if (rc)
1165 		goto out_unlock;
1166 
1167 	rc = nd_desc->ndctl(nd_desc, nvdimm, cmd, buf, buf_len, &cmd_rc);
1168 	if (rc < 0)
1169 		goto out_unlock;
1170 
1171 	if (!nvdimm && cmd == ND_CMD_CLEAR_ERROR && cmd_rc >= 0) {
1172 		struct nd_cmd_clear_error *clear_err = buf;
1173 
1174 		nvdimm_account_cleared_poison(nvdimm_bus, clear_err->address,
1175 				clear_err->cleared);
1176 	}
1177 
1178 	if (copy_to_user(p, buf, buf_len))
1179 		rc = -EFAULT;
1180 
1181 out_unlock:
1182 	nvdimm_bus_unlock(dev);
1183 	nd_device_unlock(dev);
1184 out:
1185 	kfree(in_env);
1186 	kfree(out_env);
1187 	vfree(buf);
1188 	return rc;
1189 }
1190 
1191 enum nd_ioctl_mode {
1192 	BUS_IOCTL,
1193 	DIMM_IOCTL,
1194 };
1195 
1196 static int match_dimm(struct device *dev, void *data)
1197 {
1198 	long id = (long) data;
1199 
1200 	if (is_nvdimm(dev)) {
1201 		struct nvdimm *nvdimm = to_nvdimm(dev);
1202 
1203 		return nvdimm->id == id;
1204 	}
1205 
1206 	return 0;
1207 }
1208 
1209 static long nd_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
1210 		enum nd_ioctl_mode mode)
1211 
1212 {
1213 	struct nvdimm_bus *nvdimm_bus, *found = NULL;
1214 	long id = (long) file->private_data;
1215 	struct nvdimm *nvdimm = NULL;
1216 	int rc, ro;
1217 
1218 	ro = ((file->f_flags & O_ACCMODE) == O_RDONLY);
1219 	mutex_lock(&nvdimm_bus_list_mutex);
1220 	list_for_each_entry(nvdimm_bus, &nvdimm_bus_list, list) {
1221 		if (mode == DIMM_IOCTL) {
1222 			struct device *dev;
1223 
1224 			dev = device_find_child(&nvdimm_bus->dev,
1225 					file->private_data, match_dimm);
1226 			if (!dev)
1227 				continue;
1228 			nvdimm = to_nvdimm(dev);
1229 			found = nvdimm_bus;
1230 		} else if (nvdimm_bus->id == id) {
1231 			found = nvdimm_bus;
1232 		}
1233 
1234 		if (found) {
1235 			atomic_inc(&nvdimm_bus->ioctl_active);
1236 			break;
1237 		}
1238 	}
1239 	mutex_unlock(&nvdimm_bus_list_mutex);
1240 
1241 	if (!found)
1242 		return -ENXIO;
1243 
1244 	nvdimm_bus = found;
1245 	rc = __nd_ioctl(nvdimm_bus, nvdimm, ro, cmd, arg);
1246 
1247 	if (nvdimm)
1248 		put_device(&nvdimm->dev);
1249 	if (atomic_dec_and_test(&nvdimm_bus->ioctl_active))
1250 		wake_up(&nvdimm_bus->wait);
1251 
1252 	return rc;
1253 }
1254 
1255 static long bus_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1256 {
1257 	return nd_ioctl(file, cmd, arg, BUS_IOCTL);
1258 }
1259 
1260 static long dimm_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1261 {
1262 	return nd_ioctl(file, cmd, arg, DIMM_IOCTL);
1263 }
1264 
1265 static int nd_open(struct inode *inode, struct file *file)
1266 {
1267 	long minor = iminor(inode);
1268 
1269 	file->private_data = (void *) minor;
1270 	return 0;
1271 }
1272 
1273 static const struct file_operations nvdimm_bus_fops = {
1274 	.owner = THIS_MODULE,
1275 	.open = nd_open,
1276 	.unlocked_ioctl = bus_ioctl,
1277 	.compat_ioctl = compat_ptr_ioctl,
1278 	.llseek = noop_llseek,
1279 };
1280 
1281 static const struct file_operations nvdimm_fops = {
1282 	.owner = THIS_MODULE,
1283 	.open = nd_open,
1284 	.unlocked_ioctl = dimm_ioctl,
1285 	.compat_ioctl = compat_ptr_ioctl,
1286 	.llseek = noop_llseek,
1287 };
1288 
1289 int __init nvdimm_bus_init(void)
1290 {
1291 	int rc;
1292 
1293 	rc = bus_register(&nvdimm_bus_type);
1294 	if (rc)
1295 		return rc;
1296 
1297 	rc = register_chrdev(0, "ndctl", &nvdimm_bus_fops);
1298 	if (rc < 0)
1299 		goto err_bus_chrdev;
1300 	nvdimm_bus_major = rc;
1301 
1302 	rc = register_chrdev(0, "dimmctl", &nvdimm_fops);
1303 	if (rc < 0)
1304 		goto err_dimm_chrdev;
1305 	nvdimm_major = rc;
1306 
1307 	nd_class = class_create(THIS_MODULE, "nd");
1308 	if (IS_ERR(nd_class)) {
1309 		rc = PTR_ERR(nd_class);
1310 		goto err_class;
1311 	}
1312 
1313 	rc = driver_register(&nd_bus_driver.drv);
1314 	if (rc)
1315 		goto err_nd_bus;
1316 
1317 	return 0;
1318 
1319  err_nd_bus:
1320 	class_destroy(nd_class);
1321  err_class:
1322 	unregister_chrdev(nvdimm_major, "dimmctl");
1323  err_dimm_chrdev:
1324 	unregister_chrdev(nvdimm_bus_major, "ndctl");
1325  err_bus_chrdev:
1326 	bus_unregister(&nvdimm_bus_type);
1327 
1328 	return rc;
1329 }
1330 
1331 void nvdimm_bus_exit(void)
1332 {
1333 	driver_unregister(&nd_bus_driver.drv);
1334 	class_destroy(nd_class);
1335 	unregister_chrdev(nvdimm_bus_major, "ndctl");
1336 	unregister_chrdev(nvdimm_major, "dimmctl");
1337 	bus_unregister(&nvdimm_bus_type);
1338 	ida_destroy(&nd_ida);
1339 }
1340