xref: /linux/drivers/nvdimm/bus.c (revision bfb921b2a9d5d1123d1d10b196a39db629ddef87)
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 struct class *nd_class;
29 static DEFINE_IDA(nd_ida);
30 
31 static int to_nd_device_type(const struct device *dev)
32 {
33 	if (is_nvdimm(dev))
34 		return ND_DEVICE_DIMM;
35 	else if (is_memory(dev))
36 		return ND_DEVICE_REGION_PMEM;
37 	else if (is_nd_dax(dev))
38 		return ND_DEVICE_DAX_PMEM;
39 	else if (is_nd_region(dev->parent))
40 		return nd_region_to_nstype(to_nd_region(dev->parent));
41 
42 	return 0;
43 }
44 
45 static int nvdimm_bus_uevent(const struct device *dev, struct kobj_uevent_env *env)
46 {
47 	return add_uevent_var(env, "MODALIAS=" ND_DEVICE_MODALIAS_FMT,
48 			to_nd_device_type(dev));
49 }
50 
51 static struct module *to_bus_provider(struct device *dev)
52 {
53 	/* pin bus providers while regions are enabled */
54 	if (is_nd_region(dev)) {
55 		struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
56 
57 		return nvdimm_bus->nd_desc->module;
58 	}
59 	return NULL;
60 }
61 
62 static void nvdimm_bus_probe_start(struct nvdimm_bus *nvdimm_bus)
63 {
64 	nvdimm_bus_lock(&nvdimm_bus->dev);
65 	nvdimm_bus->probe_active++;
66 	nvdimm_bus_unlock(&nvdimm_bus->dev);
67 }
68 
69 static void nvdimm_bus_probe_end(struct nvdimm_bus *nvdimm_bus)
70 {
71 	nvdimm_bus_lock(&nvdimm_bus->dev);
72 	if (--nvdimm_bus->probe_active == 0)
73 		wake_up(&nvdimm_bus->wait);
74 	nvdimm_bus_unlock(&nvdimm_bus->dev);
75 }
76 
77 static int nvdimm_bus_probe(struct device *dev)
78 {
79 	struct nd_device_driver *nd_drv = to_nd_device_driver(dev->driver);
80 	struct module *provider = to_bus_provider(dev);
81 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
82 	int rc;
83 
84 	if (!try_module_get(provider))
85 		return -ENXIO;
86 
87 	dev_dbg(&nvdimm_bus->dev, "START: %s.probe(%s)\n",
88 			dev->driver->name, dev_name(dev));
89 
90 	nvdimm_bus_probe_start(nvdimm_bus);
91 	rc = nd_drv->probe(dev);
92 	if ((rc == 0 || rc == -EOPNOTSUPP) &&
93 			dev->parent && is_nd_region(dev->parent))
94 		nd_region_advance_seeds(to_nd_region(dev->parent), dev);
95 	nvdimm_bus_probe_end(nvdimm_bus);
96 
97 	dev_dbg(&nvdimm_bus->dev, "END: %s.probe(%s) = %d\n", dev->driver->name,
98 			dev_name(dev), rc);
99 
100 	if (rc != 0)
101 		module_put(provider);
102 	return rc;
103 }
104 
105 static void nvdimm_bus_remove(struct device *dev)
106 {
107 	struct nd_device_driver *nd_drv = to_nd_device_driver(dev->driver);
108 	struct module *provider = to_bus_provider(dev);
109 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
110 
111 	if (nd_drv->remove)
112 		nd_drv->remove(dev);
113 
114 	dev_dbg(&nvdimm_bus->dev, "%s.remove(%s)\n", dev->driver->name,
115 			dev_name(dev));
116 	module_put(provider);
117 }
118 
119 static void nvdimm_bus_shutdown(struct device *dev)
120 {
121 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
122 	struct nd_device_driver *nd_drv = NULL;
123 
124 	if (dev->driver)
125 		nd_drv = to_nd_device_driver(dev->driver);
126 
127 	if (nd_drv && nd_drv->shutdown) {
128 		nd_drv->shutdown(dev);
129 		dev_dbg(&nvdimm_bus->dev, "%s.shutdown(%s)\n",
130 				dev->driver->name, dev_name(dev));
131 	}
132 }
133 
134 void nd_device_notify(struct device *dev, enum nvdimm_event event)
135 {
136 	device_lock(dev);
137 	if (dev->driver) {
138 		struct nd_device_driver *nd_drv;
139 
140 		nd_drv = to_nd_device_driver(dev->driver);
141 		if (nd_drv->notify)
142 			nd_drv->notify(dev, event);
143 	}
144 	device_unlock(dev);
145 }
146 EXPORT_SYMBOL(nd_device_notify);
147 
148 void nvdimm_region_notify(struct nd_region *nd_region, enum nvdimm_event event)
149 {
150 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&nd_region->dev);
151 
152 	if (!nvdimm_bus)
153 		return;
154 
155 	/* caller is responsible for holding a reference on the device */
156 	nd_device_notify(&nd_region->dev, event);
157 }
158 EXPORT_SYMBOL_GPL(nvdimm_region_notify);
159 
160 struct clear_badblocks_context {
161 	resource_size_t phys, cleared;
162 };
163 
164 static int nvdimm_clear_badblocks_region(struct device *dev, void *data)
165 {
166 	struct clear_badblocks_context *ctx = data;
167 	struct nd_region *nd_region;
168 	resource_size_t ndr_end;
169 	sector_t sector;
170 
171 	/* make sure device is a region */
172 	if (!is_memory(dev))
173 		return 0;
174 
175 	nd_region = to_nd_region(dev);
176 	ndr_end = nd_region->ndr_start + nd_region->ndr_size - 1;
177 
178 	/* make sure we are in the region */
179 	if (ctx->phys < nd_region->ndr_start ||
180 	    (ctx->phys + ctx->cleared - 1) > ndr_end)
181 		return 0;
182 
183 	sector = (ctx->phys - nd_region->ndr_start) / 512;
184 	badblocks_clear(&nd_region->bb, sector, ctx->cleared / 512);
185 
186 	if (nd_region->bb_state)
187 		sysfs_notify_dirent(nd_region->bb_state);
188 
189 	return 0;
190 }
191 
192 static void nvdimm_clear_badblocks_regions(struct nvdimm_bus *nvdimm_bus,
193 		phys_addr_t phys, u64 cleared)
194 {
195 	struct clear_badblocks_context ctx = {
196 		.phys = phys,
197 		.cleared = cleared,
198 	};
199 
200 	device_for_each_child(&nvdimm_bus->dev, &ctx,
201 			nvdimm_clear_badblocks_region);
202 }
203 
204 static void nvdimm_account_cleared_poison(struct nvdimm_bus *nvdimm_bus,
205 		phys_addr_t phys, u64 cleared)
206 {
207 	if (cleared > 0)
208 		badrange_forget(&nvdimm_bus->badrange, phys, cleared);
209 
210 	if (cleared > 0 && cleared / 512)
211 		nvdimm_clear_badblocks_regions(nvdimm_bus, phys, cleared);
212 }
213 
214 long nvdimm_clear_poison(struct device *dev, phys_addr_t phys,
215 		unsigned int len)
216 {
217 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
218 	struct nvdimm_bus_descriptor *nd_desc;
219 	struct nd_cmd_clear_error clear_err;
220 	struct nd_cmd_ars_cap ars_cap;
221 	u32 clear_err_unit, mask;
222 	unsigned int noio_flag;
223 	int cmd_rc, rc;
224 
225 	if (!nvdimm_bus)
226 		return -ENXIO;
227 
228 	nd_desc = nvdimm_bus->nd_desc;
229 	/*
230 	 * if ndctl does not exist, it's PMEM_LEGACY and
231 	 * we want to just pretend everything is handled.
232 	 */
233 	if (!nd_desc->ndctl)
234 		return len;
235 
236 	memset(&ars_cap, 0, sizeof(ars_cap));
237 	ars_cap.address = phys;
238 	ars_cap.length = len;
239 	noio_flag = memalloc_noio_save();
240 	rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_ARS_CAP, &ars_cap,
241 			sizeof(ars_cap), &cmd_rc);
242 	memalloc_noio_restore(noio_flag);
243 	if (rc < 0)
244 		return rc;
245 	if (cmd_rc < 0)
246 		return cmd_rc;
247 	clear_err_unit = ars_cap.clear_err_unit;
248 	if (!clear_err_unit || !is_power_of_2(clear_err_unit))
249 		return -ENXIO;
250 
251 	mask = clear_err_unit - 1;
252 	if ((phys | len) & mask)
253 		return -ENXIO;
254 	memset(&clear_err, 0, sizeof(clear_err));
255 	clear_err.address = phys;
256 	clear_err.length = len;
257 	noio_flag = memalloc_noio_save();
258 	rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_CLEAR_ERROR, &clear_err,
259 			sizeof(clear_err), &cmd_rc);
260 	memalloc_noio_restore(noio_flag);
261 	if (rc < 0)
262 		return rc;
263 	if (cmd_rc < 0)
264 		return cmd_rc;
265 
266 	nvdimm_account_cleared_poison(nvdimm_bus, phys, clear_err.cleared);
267 
268 	return clear_err.cleared;
269 }
270 EXPORT_SYMBOL_GPL(nvdimm_clear_poison);
271 
272 static int nvdimm_bus_match(struct device *dev, struct device_driver *drv);
273 
274 static const struct bus_type nvdimm_bus_type = {
275 	.name = "nd",
276 	.uevent = nvdimm_bus_uevent,
277 	.match = nvdimm_bus_match,
278 	.probe = nvdimm_bus_probe,
279 	.remove = nvdimm_bus_remove,
280 	.shutdown = nvdimm_bus_shutdown,
281 };
282 
283 static void nvdimm_bus_release(struct device *dev)
284 {
285 	struct nvdimm_bus *nvdimm_bus;
286 
287 	nvdimm_bus = container_of(dev, struct nvdimm_bus, dev);
288 	ida_free(&nd_ida, nvdimm_bus->id);
289 	kfree(nvdimm_bus);
290 }
291 
292 static const struct device_type nvdimm_bus_dev_type = {
293 	.release = nvdimm_bus_release,
294 	.groups = nvdimm_bus_attribute_groups,
295 };
296 
297 bool is_nvdimm_bus(struct device *dev)
298 {
299 	return dev->type == &nvdimm_bus_dev_type;
300 }
301 
302 struct nvdimm_bus *walk_to_nvdimm_bus(struct device *nd_dev)
303 {
304 	struct device *dev;
305 
306 	for (dev = nd_dev; dev; dev = dev->parent)
307 		if (is_nvdimm_bus(dev))
308 			break;
309 	dev_WARN_ONCE(nd_dev, !dev, "invalid dev, not on nd bus\n");
310 	if (dev)
311 		return to_nvdimm_bus(dev);
312 	return NULL;
313 }
314 
315 struct nvdimm_bus *to_nvdimm_bus(struct device *dev)
316 {
317 	struct nvdimm_bus *nvdimm_bus;
318 
319 	nvdimm_bus = container_of(dev, struct nvdimm_bus, dev);
320 	WARN_ON(!is_nvdimm_bus(dev));
321 	return nvdimm_bus;
322 }
323 EXPORT_SYMBOL_GPL(to_nvdimm_bus);
324 
325 struct nvdimm_bus *nvdimm_to_bus(struct nvdimm *nvdimm)
326 {
327 	return to_nvdimm_bus(nvdimm->dev.parent);
328 }
329 EXPORT_SYMBOL_GPL(nvdimm_to_bus);
330 
331 static struct lock_class_key nvdimm_bus_key;
332 
333 struct nvdimm_bus *nvdimm_bus_register(struct device *parent,
334 		struct nvdimm_bus_descriptor *nd_desc)
335 {
336 	struct nvdimm_bus *nvdimm_bus;
337 	int rc;
338 
339 	nvdimm_bus = kzalloc(sizeof(*nvdimm_bus), GFP_KERNEL);
340 	if (!nvdimm_bus)
341 		return NULL;
342 	INIT_LIST_HEAD(&nvdimm_bus->list);
343 	INIT_LIST_HEAD(&nvdimm_bus->mapping_list);
344 	init_waitqueue_head(&nvdimm_bus->wait);
345 	nvdimm_bus->id = ida_alloc(&nd_ida, GFP_KERNEL);
346 	if (nvdimm_bus->id < 0) {
347 		kfree(nvdimm_bus);
348 		return NULL;
349 	}
350 	mutex_init(&nvdimm_bus->reconfig_mutex);
351 	badrange_init(&nvdimm_bus->badrange);
352 	nvdimm_bus->nd_desc = nd_desc;
353 	nvdimm_bus->dev.parent = parent;
354 	nvdimm_bus->dev.type = &nvdimm_bus_dev_type;
355 	nvdimm_bus->dev.groups = nd_desc->attr_groups;
356 	nvdimm_bus->dev.bus = &nvdimm_bus_type;
357 	nvdimm_bus->dev.of_node = nd_desc->of_node;
358 	device_initialize(&nvdimm_bus->dev);
359 	lockdep_set_class(&nvdimm_bus->dev.mutex, &nvdimm_bus_key);
360 	device_set_pm_not_required(&nvdimm_bus->dev);
361 	rc = dev_set_name(&nvdimm_bus->dev, "ndbus%d", nvdimm_bus->id);
362 	if (rc)
363 		goto err;
364 
365 	rc = device_add(&nvdimm_bus->dev);
366 	if (rc) {
367 		dev_dbg(&nvdimm_bus->dev, "registration failed: %d\n", rc);
368 		goto err;
369 	}
370 
371 	return nvdimm_bus;
372  err:
373 	put_device(&nvdimm_bus->dev);
374 	return NULL;
375 }
376 EXPORT_SYMBOL_GPL(nvdimm_bus_register);
377 
378 void nvdimm_bus_unregister(struct nvdimm_bus *nvdimm_bus)
379 {
380 	if (!nvdimm_bus)
381 		return;
382 	device_unregister(&nvdimm_bus->dev);
383 }
384 EXPORT_SYMBOL_GPL(nvdimm_bus_unregister);
385 
386 static int child_unregister(struct device *dev, void *data)
387 {
388 	/*
389 	 * the singular ndctl class device per bus needs to be
390 	 * "device_destroy"ed, so skip it here
391 	 *
392 	 * i.e. remove classless children
393 	 */
394 	if (dev->class)
395 		return 0;
396 
397 	if (is_nvdimm(dev))
398 		nvdimm_delete(to_nvdimm(dev));
399 	else
400 		nd_device_unregister(dev, ND_SYNC);
401 
402 	return 0;
403 }
404 
405 static void free_badrange_list(struct list_head *badrange_list)
406 {
407 	struct badrange_entry *bre, *next;
408 
409 	list_for_each_entry_safe(bre, next, badrange_list, list) {
410 		list_del(&bre->list);
411 		kfree(bre);
412 	}
413 	list_del_init(badrange_list);
414 }
415 
416 static void nd_bus_remove(struct device *dev)
417 {
418 	struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
419 
420 	mutex_lock(&nvdimm_bus_list_mutex);
421 	list_del_init(&nvdimm_bus->list);
422 	mutex_unlock(&nvdimm_bus_list_mutex);
423 
424 	wait_event(nvdimm_bus->wait,
425 			atomic_read(&nvdimm_bus->ioctl_active) == 0);
426 
427 	nd_synchronize();
428 	device_for_each_child(&nvdimm_bus->dev, NULL, child_unregister);
429 
430 	spin_lock(&nvdimm_bus->badrange.lock);
431 	free_badrange_list(&nvdimm_bus->badrange.list);
432 	spin_unlock(&nvdimm_bus->badrange.lock);
433 
434 	nvdimm_bus_destroy_ndctl(nvdimm_bus);
435 }
436 
437 static int nd_bus_probe(struct device *dev)
438 {
439 	struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
440 	int rc;
441 
442 	rc = nvdimm_bus_create_ndctl(nvdimm_bus);
443 	if (rc)
444 		return rc;
445 
446 	mutex_lock(&nvdimm_bus_list_mutex);
447 	list_add_tail(&nvdimm_bus->list, &nvdimm_bus_list);
448 	mutex_unlock(&nvdimm_bus_list_mutex);
449 
450 	/* enable bus provider attributes to look up their local context */
451 	dev_set_drvdata(dev, nvdimm_bus->nd_desc);
452 
453 	return 0;
454 }
455 
456 static struct nd_device_driver nd_bus_driver = {
457 	.probe = nd_bus_probe,
458 	.remove = nd_bus_remove,
459 	.drv = {
460 		.name = "nd_bus",
461 		.suppress_bind_attrs = true,
462 		.bus = &nvdimm_bus_type,
463 		.owner = THIS_MODULE,
464 		.mod_name = KBUILD_MODNAME,
465 	},
466 };
467 
468 static int nvdimm_bus_match(struct device *dev, struct device_driver *drv)
469 {
470 	struct nd_device_driver *nd_drv = to_nd_device_driver(drv);
471 
472 	if (is_nvdimm_bus(dev) && nd_drv == &nd_bus_driver)
473 		return true;
474 
475 	return !!test_bit(to_nd_device_type(dev), &nd_drv->type);
476 }
477 
478 static ASYNC_DOMAIN_EXCLUSIVE(nd_async_domain);
479 
480 void nd_synchronize(void)
481 {
482 	async_synchronize_full_domain(&nd_async_domain);
483 }
484 EXPORT_SYMBOL_GPL(nd_synchronize);
485 
486 static void nd_async_device_register(void *d, async_cookie_t cookie)
487 {
488 	struct device *dev = d;
489 
490 	if (device_add(dev) != 0) {
491 		dev_err(dev, "%s: failed\n", __func__);
492 		put_device(dev);
493 	}
494 	put_device(dev);
495 	if (dev->parent)
496 		put_device(dev->parent);
497 }
498 
499 static void nd_async_device_unregister(void *d, async_cookie_t cookie)
500 {
501 	struct device *dev = d;
502 
503 	/* flush bus operations before delete */
504 	nvdimm_bus_lock(dev);
505 	nvdimm_bus_unlock(dev);
506 
507 	device_unregister(dev);
508 	put_device(dev);
509 }
510 
511 static void __nd_device_register(struct device *dev, bool sync)
512 {
513 	if (!dev)
514 		return;
515 
516 	/*
517 	 * Ensure that region devices always have their NUMA node set as
518 	 * early as possible. This way we are able to make certain that
519 	 * any memory associated with the creation and the creation
520 	 * itself of the region is associated with the correct node.
521 	 */
522 	if (is_nd_region(dev))
523 		set_dev_node(dev, to_nd_region(dev)->numa_node);
524 
525 	dev->bus = &nvdimm_bus_type;
526 	device_set_pm_not_required(dev);
527 	if (dev->parent) {
528 		get_device(dev->parent);
529 		if (dev_to_node(dev) == NUMA_NO_NODE)
530 			set_dev_node(dev, dev_to_node(dev->parent));
531 	}
532 	get_device(dev);
533 
534 	if (sync)
535 		nd_async_device_register(dev, 0);
536 	else
537 		async_schedule_dev_domain(nd_async_device_register, dev,
538 					  &nd_async_domain);
539 }
540 
541 void nd_device_register(struct device *dev)
542 {
543 	__nd_device_register(dev, false);
544 }
545 EXPORT_SYMBOL(nd_device_register);
546 
547 void nd_device_register_sync(struct device *dev)
548 {
549 	__nd_device_register(dev, true);
550 }
551 
552 void nd_device_unregister(struct device *dev, enum nd_async_mode mode)
553 {
554 	bool killed;
555 
556 	switch (mode) {
557 	case ND_ASYNC:
558 		/*
559 		 * In the async case this is being triggered with the
560 		 * device lock held and the unregistration work needs to
561 		 * be moved out of line iff this is thread has won the
562 		 * race to schedule the deletion.
563 		 */
564 		if (!kill_device(dev))
565 			return;
566 
567 		get_device(dev);
568 		async_schedule_domain(nd_async_device_unregister, dev,
569 				&nd_async_domain);
570 		break;
571 	case ND_SYNC:
572 		/*
573 		 * In the sync case the device is being unregistered due
574 		 * to a state change of the parent. Claim the kill state
575 		 * to synchronize against other unregistration requests,
576 		 * or otherwise let the async path handle it if the
577 		 * unregistration was already queued.
578 		 */
579 		device_lock(dev);
580 		killed = kill_device(dev);
581 		device_unlock(dev);
582 
583 		if (!killed)
584 			return;
585 
586 		nd_synchronize();
587 		device_unregister(dev);
588 		break;
589 	}
590 }
591 EXPORT_SYMBOL(nd_device_unregister);
592 
593 /**
594  * __nd_driver_register() - register a region or a namespace driver
595  * @nd_drv: driver to register
596  * @owner: automatically set by nd_driver_register() macro
597  * @mod_name: automatically set by nd_driver_register() macro
598  */
599 int __nd_driver_register(struct nd_device_driver *nd_drv, struct module *owner,
600 		const char *mod_name)
601 {
602 	struct device_driver *drv = &nd_drv->drv;
603 
604 	if (!nd_drv->type) {
605 		pr_debug("driver type bitmask not set (%ps)\n",
606 				__builtin_return_address(0));
607 		return -EINVAL;
608 	}
609 
610 	if (!nd_drv->probe) {
611 		pr_debug("%s ->probe() must be specified\n", mod_name);
612 		return -EINVAL;
613 	}
614 
615 	drv->bus = &nvdimm_bus_type;
616 	drv->owner = owner;
617 	drv->mod_name = mod_name;
618 
619 	return driver_register(drv);
620 }
621 EXPORT_SYMBOL(__nd_driver_register);
622 
623 void nvdimm_check_and_set_ro(struct gendisk *disk)
624 {
625 	struct device *dev = disk_to_dev(disk)->parent;
626 	struct nd_region *nd_region = to_nd_region(dev->parent);
627 	int disk_ro = get_disk_ro(disk);
628 
629 	/* catch the disk up with the region ro state */
630 	if (disk_ro == nd_region->ro)
631 		return;
632 
633 	dev_info(dev, "%s read-%s, marking %s read-%s\n",
634 		 dev_name(&nd_region->dev), nd_region->ro ? "only" : "write",
635 		 disk->disk_name, nd_region->ro ? "only" : "write");
636 	set_disk_ro(disk, nd_region->ro);
637 }
638 EXPORT_SYMBOL(nvdimm_check_and_set_ro);
639 
640 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
641 		char *buf)
642 {
643 	return sprintf(buf, ND_DEVICE_MODALIAS_FMT "\n",
644 			to_nd_device_type(dev));
645 }
646 static DEVICE_ATTR_RO(modalias);
647 
648 static ssize_t devtype_show(struct device *dev, struct device_attribute *attr,
649 		char *buf)
650 {
651 	return sprintf(buf, "%s\n", dev->type->name);
652 }
653 static DEVICE_ATTR_RO(devtype);
654 
655 static struct attribute *nd_device_attributes[] = {
656 	&dev_attr_modalias.attr,
657 	&dev_attr_devtype.attr,
658 	NULL,
659 };
660 
661 /*
662  * nd_device_attribute_group - generic attributes for all devices on an nd bus
663  */
664 const struct attribute_group nd_device_attribute_group = {
665 	.attrs = nd_device_attributes,
666 };
667 
668 static ssize_t numa_node_show(struct device *dev,
669 		struct device_attribute *attr, char *buf)
670 {
671 	return sprintf(buf, "%d\n", dev_to_node(dev));
672 }
673 static DEVICE_ATTR_RO(numa_node);
674 
675 static int nvdimm_dev_to_target_node(struct device *dev)
676 {
677 	struct device *parent = dev->parent;
678 	struct nd_region *nd_region = NULL;
679 
680 	if (is_nd_region(dev))
681 		nd_region = to_nd_region(dev);
682 	else if (parent && is_nd_region(parent))
683 		nd_region = to_nd_region(parent);
684 
685 	if (!nd_region)
686 		return NUMA_NO_NODE;
687 	return nd_region->target_node;
688 }
689 
690 static ssize_t target_node_show(struct device *dev,
691 		struct device_attribute *attr, char *buf)
692 {
693 	return sprintf(buf, "%d\n", nvdimm_dev_to_target_node(dev));
694 }
695 static DEVICE_ATTR_RO(target_node);
696 
697 static struct attribute *nd_numa_attributes[] = {
698 	&dev_attr_numa_node.attr,
699 	&dev_attr_target_node.attr,
700 	NULL,
701 };
702 
703 static umode_t nd_numa_attr_visible(struct kobject *kobj, struct attribute *a,
704 		int n)
705 {
706 	struct device *dev = container_of(kobj, typeof(*dev), kobj);
707 
708 	if (!IS_ENABLED(CONFIG_NUMA))
709 		return 0;
710 
711 	if (a == &dev_attr_target_node.attr &&
712 			nvdimm_dev_to_target_node(dev) == NUMA_NO_NODE)
713 		return 0;
714 
715 	return a->mode;
716 }
717 
718 /*
719  * nd_numa_attribute_group - NUMA attributes for all devices on an nd bus
720  */
721 const struct attribute_group nd_numa_attribute_group = {
722 	.attrs = nd_numa_attributes,
723 	.is_visible = nd_numa_attr_visible,
724 };
725 
726 static void ndctl_release(struct device *dev)
727 {
728 	kfree(dev);
729 }
730 
731 static struct lock_class_key nvdimm_ndctl_key;
732 
733 int nvdimm_bus_create_ndctl(struct nvdimm_bus *nvdimm_bus)
734 {
735 	dev_t devt = MKDEV(nvdimm_bus_major, nvdimm_bus->id);
736 	struct device *dev;
737 	int rc;
738 
739 	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
740 	if (!dev)
741 		return -ENOMEM;
742 	device_initialize(dev);
743 	lockdep_set_class(&dev->mutex, &nvdimm_ndctl_key);
744 	device_set_pm_not_required(dev);
745 	dev->class = nd_class;
746 	dev->parent = &nvdimm_bus->dev;
747 	dev->devt = devt;
748 	dev->release = ndctl_release;
749 	rc = dev_set_name(dev, "ndctl%d", nvdimm_bus->id);
750 	if (rc)
751 		goto err;
752 
753 	rc = device_add(dev);
754 	if (rc) {
755 		dev_dbg(&nvdimm_bus->dev, "failed to register ndctl%d: %d\n",
756 				nvdimm_bus->id, rc);
757 		goto err;
758 	}
759 	return 0;
760 
761 err:
762 	put_device(dev);
763 	return rc;
764 }
765 
766 void nvdimm_bus_destroy_ndctl(struct nvdimm_bus *nvdimm_bus)
767 {
768 	device_destroy(nd_class, MKDEV(nvdimm_bus_major, nvdimm_bus->id));
769 }
770 
771 static const struct nd_cmd_desc __nd_cmd_dimm_descs[] = {
772 	[ND_CMD_IMPLEMENTED] = { },
773 	[ND_CMD_SMART] = {
774 		.out_num = 2,
775 		.out_sizes = { 4, 128, },
776 	},
777 	[ND_CMD_SMART_THRESHOLD] = {
778 		.out_num = 2,
779 		.out_sizes = { 4, 8, },
780 	},
781 	[ND_CMD_DIMM_FLAGS] = {
782 		.out_num = 2,
783 		.out_sizes = { 4, 4 },
784 	},
785 	[ND_CMD_GET_CONFIG_SIZE] = {
786 		.out_num = 3,
787 		.out_sizes = { 4, 4, 4, },
788 	},
789 	[ND_CMD_GET_CONFIG_DATA] = {
790 		.in_num = 2,
791 		.in_sizes = { 4, 4, },
792 		.out_num = 2,
793 		.out_sizes = { 4, UINT_MAX, },
794 	},
795 	[ND_CMD_SET_CONFIG_DATA] = {
796 		.in_num = 3,
797 		.in_sizes = { 4, 4, UINT_MAX, },
798 		.out_num = 1,
799 		.out_sizes = { 4, },
800 	},
801 	[ND_CMD_VENDOR] = {
802 		.in_num = 3,
803 		.in_sizes = { 4, 4, UINT_MAX, },
804 		.out_num = 3,
805 		.out_sizes = { 4, 4, UINT_MAX, },
806 	},
807 	[ND_CMD_CALL] = {
808 		.in_num = 2,
809 		.in_sizes = { sizeof(struct nd_cmd_pkg), UINT_MAX, },
810 		.out_num = 1,
811 		.out_sizes = { UINT_MAX, },
812 	},
813 };
814 
815 const struct nd_cmd_desc *nd_cmd_dimm_desc(int cmd)
816 {
817 	if (cmd < ARRAY_SIZE(__nd_cmd_dimm_descs))
818 		return &__nd_cmd_dimm_descs[cmd];
819 	return NULL;
820 }
821 EXPORT_SYMBOL_GPL(nd_cmd_dimm_desc);
822 
823 static const struct nd_cmd_desc __nd_cmd_bus_descs[] = {
824 	[ND_CMD_IMPLEMENTED] = { },
825 	[ND_CMD_ARS_CAP] = {
826 		.in_num = 2,
827 		.in_sizes = { 8, 8, },
828 		.out_num = 4,
829 		.out_sizes = { 4, 4, 4, 4, },
830 	},
831 	[ND_CMD_ARS_START] = {
832 		.in_num = 5,
833 		.in_sizes = { 8, 8, 2, 1, 5, },
834 		.out_num = 2,
835 		.out_sizes = { 4, 4, },
836 	},
837 	[ND_CMD_ARS_STATUS] = {
838 		.out_num = 3,
839 		.out_sizes = { 4, 4, UINT_MAX, },
840 	},
841 	[ND_CMD_CLEAR_ERROR] = {
842 		.in_num = 2,
843 		.in_sizes = { 8, 8, },
844 		.out_num = 3,
845 		.out_sizes = { 4, 4, 8, },
846 	},
847 	[ND_CMD_CALL] = {
848 		.in_num = 2,
849 		.in_sizes = { sizeof(struct nd_cmd_pkg), UINT_MAX, },
850 		.out_num = 1,
851 		.out_sizes = { UINT_MAX, },
852 	},
853 };
854 
855 const struct nd_cmd_desc *nd_cmd_bus_desc(int cmd)
856 {
857 	if (cmd < ARRAY_SIZE(__nd_cmd_bus_descs))
858 		return &__nd_cmd_bus_descs[cmd];
859 	return NULL;
860 }
861 EXPORT_SYMBOL_GPL(nd_cmd_bus_desc);
862 
863 u32 nd_cmd_in_size(struct nvdimm *nvdimm, int cmd,
864 		const struct nd_cmd_desc *desc, int idx, void *buf)
865 {
866 	if (idx >= desc->in_num)
867 		return UINT_MAX;
868 
869 	if (desc->in_sizes[idx] < UINT_MAX)
870 		return desc->in_sizes[idx];
871 
872 	if (nvdimm && cmd == ND_CMD_SET_CONFIG_DATA && idx == 2) {
873 		struct nd_cmd_set_config_hdr *hdr = buf;
874 
875 		return hdr->in_length;
876 	} else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2) {
877 		struct nd_cmd_vendor_hdr *hdr = buf;
878 
879 		return hdr->in_length;
880 	} else if (cmd == ND_CMD_CALL) {
881 		struct nd_cmd_pkg *pkg = buf;
882 
883 		return pkg->nd_size_in;
884 	}
885 
886 	return UINT_MAX;
887 }
888 EXPORT_SYMBOL_GPL(nd_cmd_in_size);
889 
890 u32 nd_cmd_out_size(struct nvdimm *nvdimm, int cmd,
891 		const struct nd_cmd_desc *desc, int idx, const u32 *in_field,
892 		const u32 *out_field, unsigned long remainder)
893 {
894 	if (idx >= desc->out_num)
895 		return UINT_MAX;
896 
897 	if (desc->out_sizes[idx] < UINT_MAX)
898 		return desc->out_sizes[idx];
899 
900 	if (nvdimm && cmd == ND_CMD_GET_CONFIG_DATA && idx == 1)
901 		return in_field[1];
902 	else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2)
903 		return out_field[1];
904 	else if (!nvdimm && cmd == ND_CMD_ARS_STATUS && idx == 2) {
905 		/*
906 		 * Per table 9-276 ARS Data in ACPI 6.1, out_field[1] is
907 		 * "Size of Output Buffer in bytes, including this
908 		 * field."
909 		 */
910 		if (out_field[1] < 4)
911 			return 0;
912 		/*
913 		 * ACPI 6.1 is ambiguous if 'status' is included in the
914 		 * output size. If we encounter an output size that
915 		 * overshoots the remainder by 4 bytes, assume it was
916 		 * including 'status'.
917 		 */
918 		if (out_field[1] - 4 == remainder)
919 			return remainder;
920 		return out_field[1] - 8;
921 	} else if (cmd == ND_CMD_CALL) {
922 		struct nd_cmd_pkg *pkg = (struct nd_cmd_pkg *) in_field;
923 
924 		return pkg->nd_size_out;
925 	}
926 
927 
928 	return UINT_MAX;
929 }
930 EXPORT_SYMBOL_GPL(nd_cmd_out_size);
931 
932 void wait_nvdimm_bus_probe_idle(struct device *dev)
933 {
934 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
935 
936 	do {
937 		if (nvdimm_bus->probe_active == 0)
938 			break;
939 		nvdimm_bus_unlock(dev);
940 		device_unlock(dev);
941 		wait_event(nvdimm_bus->wait,
942 				nvdimm_bus->probe_active == 0);
943 		device_lock(dev);
944 		nvdimm_bus_lock(dev);
945 	} while (true);
946 }
947 
948 static int nd_pmem_forget_poison_check(struct device *dev, void *data)
949 {
950 	struct nd_cmd_clear_error *clear_err =
951 		(struct nd_cmd_clear_error *)data;
952 	struct nd_btt *nd_btt = is_nd_btt(dev) ? to_nd_btt(dev) : NULL;
953 	struct nd_pfn *nd_pfn = is_nd_pfn(dev) ? to_nd_pfn(dev) : NULL;
954 	struct nd_dax *nd_dax = is_nd_dax(dev) ? to_nd_dax(dev) : NULL;
955 	struct nd_namespace_common *ndns = NULL;
956 	struct nd_namespace_io *nsio;
957 	resource_size_t offset = 0, end_trunc = 0, start, end, pstart, pend;
958 
959 	if (nd_dax || !dev->driver)
960 		return 0;
961 
962 	start = clear_err->address;
963 	end = clear_err->address + clear_err->cleared - 1;
964 
965 	if (nd_btt || nd_pfn || nd_dax) {
966 		if (nd_btt)
967 			ndns = nd_btt->ndns;
968 		else if (nd_pfn)
969 			ndns = nd_pfn->ndns;
970 		else if (nd_dax)
971 			ndns = nd_dax->nd_pfn.ndns;
972 
973 		if (!ndns)
974 			return 0;
975 	} else
976 		ndns = to_ndns(dev);
977 
978 	nsio = to_nd_namespace_io(&ndns->dev);
979 	pstart = nsio->res.start + offset;
980 	pend = nsio->res.end - end_trunc;
981 
982 	if ((pstart >= start) && (pend <= end))
983 		return -EBUSY;
984 
985 	return 0;
986 
987 }
988 
989 static int nd_ns_forget_poison_check(struct device *dev, void *data)
990 {
991 	return device_for_each_child(dev, data, nd_pmem_forget_poison_check);
992 }
993 
994 /* set_config requires an idle interleave set */
995 static int nd_cmd_clear_to_send(struct nvdimm_bus *nvdimm_bus,
996 		struct nvdimm *nvdimm, unsigned int cmd, void *data)
997 {
998 	struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
999 
1000 	/* ask the bus provider if it would like to block this request */
1001 	if (nd_desc->clear_to_send) {
1002 		int rc = nd_desc->clear_to_send(nd_desc, nvdimm, cmd, data);
1003 
1004 		if (rc)
1005 			return rc;
1006 	}
1007 
1008 	/* require clear error to go through the pmem driver */
1009 	if (!nvdimm && cmd == ND_CMD_CLEAR_ERROR)
1010 		return device_for_each_child(&nvdimm_bus->dev, data,
1011 				nd_ns_forget_poison_check);
1012 
1013 	if (!nvdimm || cmd != ND_CMD_SET_CONFIG_DATA)
1014 		return 0;
1015 
1016 	/* prevent label manipulation while the kernel owns label updates */
1017 	wait_nvdimm_bus_probe_idle(&nvdimm_bus->dev);
1018 	if (atomic_read(&nvdimm->busy))
1019 		return -EBUSY;
1020 	return 0;
1021 }
1022 
1023 static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm,
1024 		int read_only, unsigned int ioctl_cmd, unsigned long arg)
1025 {
1026 	struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
1027 	const struct nd_cmd_desc *desc = NULL;
1028 	unsigned int cmd = _IOC_NR(ioctl_cmd);
1029 	struct device *dev = &nvdimm_bus->dev;
1030 	void __user *p = (void __user *) arg;
1031 	char *out_env = NULL, *in_env = NULL;
1032 	const char *cmd_name, *dimm_name;
1033 	u32 in_len = 0, out_len = 0;
1034 	unsigned int func = cmd;
1035 	unsigned long cmd_mask;
1036 	struct nd_cmd_pkg pkg;
1037 	int rc, i, cmd_rc;
1038 	void *buf = NULL;
1039 	u64 buf_len = 0;
1040 
1041 	if (nvdimm) {
1042 		desc = nd_cmd_dimm_desc(cmd);
1043 		cmd_name = nvdimm_cmd_name(cmd);
1044 		cmd_mask = nvdimm->cmd_mask;
1045 		dimm_name = dev_name(&nvdimm->dev);
1046 	} else {
1047 		desc = nd_cmd_bus_desc(cmd);
1048 		cmd_name = nvdimm_bus_cmd_name(cmd);
1049 		cmd_mask = nd_desc->cmd_mask;
1050 		dimm_name = "bus";
1051 	}
1052 
1053 	/* Validate command family support against bus declared support */
1054 	if (cmd == ND_CMD_CALL) {
1055 		unsigned long *mask;
1056 
1057 		if (copy_from_user(&pkg, p, sizeof(pkg)))
1058 			return -EFAULT;
1059 
1060 		if (nvdimm) {
1061 			if (pkg.nd_family > NVDIMM_FAMILY_MAX)
1062 				return -EINVAL;
1063 			mask = &nd_desc->dimm_family_mask;
1064 		} else {
1065 			if (pkg.nd_family > NVDIMM_BUS_FAMILY_MAX)
1066 				return -EINVAL;
1067 			mask = &nd_desc->bus_family_mask;
1068 		}
1069 
1070 		if (!test_bit(pkg.nd_family, mask))
1071 			return -EINVAL;
1072 	}
1073 
1074 	if (!desc ||
1075 	    (desc->out_num + desc->in_num == 0) ||
1076 	    cmd > ND_CMD_CALL ||
1077 	    !test_bit(cmd, &cmd_mask))
1078 		return -ENOTTY;
1079 
1080 	/* fail write commands (when read-only) */
1081 	if (read_only)
1082 		switch (cmd) {
1083 		case ND_CMD_VENDOR:
1084 		case ND_CMD_SET_CONFIG_DATA:
1085 		case ND_CMD_ARS_START:
1086 		case ND_CMD_CLEAR_ERROR:
1087 		case ND_CMD_CALL:
1088 			dev_dbg(dev, "'%s' command while read-only.\n",
1089 					nvdimm ? nvdimm_cmd_name(cmd)
1090 					: nvdimm_bus_cmd_name(cmd));
1091 			return -EPERM;
1092 		default:
1093 			break;
1094 		}
1095 
1096 	/* process an input envelope */
1097 	in_env = kzalloc(ND_CMD_MAX_ENVELOPE, GFP_KERNEL);
1098 	if (!in_env)
1099 		return -ENOMEM;
1100 	for (i = 0; i < desc->in_num; i++) {
1101 		u32 in_size, copy;
1102 
1103 		in_size = nd_cmd_in_size(nvdimm, cmd, desc, i, in_env);
1104 		if (in_size == UINT_MAX) {
1105 			dev_err(dev, "%s:%s unknown input size cmd: %s field: %d\n",
1106 					__func__, dimm_name, cmd_name, i);
1107 			rc = -ENXIO;
1108 			goto out;
1109 		}
1110 		if (in_len < ND_CMD_MAX_ENVELOPE)
1111 			copy = min_t(u32, ND_CMD_MAX_ENVELOPE - in_len, in_size);
1112 		else
1113 			copy = 0;
1114 		if (copy && copy_from_user(&in_env[in_len], p + in_len, copy)) {
1115 			rc = -EFAULT;
1116 			goto out;
1117 		}
1118 		in_len += in_size;
1119 	}
1120 
1121 	if (cmd == ND_CMD_CALL) {
1122 		func = pkg.nd_command;
1123 		dev_dbg(dev, "%s, idx: %llu, in: %u, out: %u, len %llu\n",
1124 				dimm_name, pkg.nd_command,
1125 				in_len, out_len, buf_len);
1126 	}
1127 
1128 	/* process an output envelope */
1129 	out_env = kzalloc(ND_CMD_MAX_ENVELOPE, GFP_KERNEL);
1130 	if (!out_env) {
1131 		rc = -ENOMEM;
1132 		goto out;
1133 	}
1134 
1135 	for (i = 0; i < desc->out_num; i++) {
1136 		u32 out_size = nd_cmd_out_size(nvdimm, cmd, desc, i,
1137 				(u32 *) in_env, (u32 *) out_env, 0);
1138 		u32 copy;
1139 
1140 		if (out_size == UINT_MAX) {
1141 			dev_dbg(dev, "%s unknown output size cmd: %s field: %d\n",
1142 					dimm_name, cmd_name, i);
1143 			rc = -EFAULT;
1144 			goto out;
1145 		}
1146 		if (out_len < ND_CMD_MAX_ENVELOPE)
1147 			copy = min_t(u32, ND_CMD_MAX_ENVELOPE - out_len, out_size);
1148 		else
1149 			copy = 0;
1150 		if (copy && copy_from_user(&out_env[out_len],
1151 					p + in_len + out_len, copy)) {
1152 			rc = -EFAULT;
1153 			goto out;
1154 		}
1155 		out_len += out_size;
1156 	}
1157 
1158 	buf_len = (u64) out_len + (u64) in_len;
1159 	if (buf_len > ND_IOCTL_MAX_BUFLEN) {
1160 		dev_dbg(dev, "%s cmd: %s buf_len: %llu > %d\n", dimm_name,
1161 				cmd_name, buf_len, ND_IOCTL_MAX_BUFLEN);
1162 		rc = -EINVAL;
1163 		goto out;
1164 	}
1165 
1166 	buf = vmalloc(buf_len);
1167 	if (!buf) {
1168 		rc = -ENOMEM;
1169 		goto out;
1170 	}
1171 
1172 	if (copy_from_user(buf, p, buf_len)) {
1173 		rc = -EFAULT;
1174 		goto out;
1175 	}
1176 
1177 	device_lock(dev);
1178 	nvdimm_bus_lock(dev);
1179 	rc = nd_cmd_clear_to_send(nvdimm_bus, nvdimm, func, buf);
1180 	if (rc)
1181 		goto out_unlock;
1182 
1183 	rc = nd_desc->ndctl(nd_desc, nvdimm, cmd, buf, buf_len, &cmd_rc);
1184 	if (rc < 0)
1185 		goto out_unlock;
1186 
1187 	if (!nvdimm && cmd == ND_CMD_CLEAR_ERROR && cmd_rc >= 0) {
1188 		struct nd_cmd_clear_error *clear_err = buf;
1189 
1190 		nvdimm_account_cleared_poison(nvdimm_bus, clear_err->address,
1191 				clear_err->cleared);
1192 	}
1193 
1194 	if (copy_to_user(p, buf, buf_len))
1195 		rc = -EFAULT;
1196 
1197 out_unlock:
1198 	nvdimm_bus_unlock(dev);
1199 	device_unlock(dev);
1200 out:
1201 	kfree(in_env);
1202 	kfree(out_env);
1203 	vfree(buf);
1204 	return rc;
1205 }
1206 
1207 enum nd_ioctl_mode {
1208 	BUS_IOCTL,
1209 	DIMM_IOCTL,
1210 };
1211 
1212 static int match_dimm(struct device *dev, void *data)
1213 {
1214 	long id = (long) data;
1215 
1216 	if (is_nvdimm(dev)) {
1217 		struct nvdimm *nvdimm = to_nvdimm(dev);
1218 
1219 		return nvdimm->id == id;
1220 	}
1221 
1222 	return 0;
1223 }
1224 
1225 static long nd_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
1226 		enum nd_ioctl_mode mode)
1227 
1228 {
1229 	struct nvdimm_bus *nvdimm_bus, *found = NULL;
1230 	long id = (long) file->private_data;
1231 	struct nvdimm *nvdimm = NULL;
1232 	int rc, ro;
1233 
1234 	ro = ((file->f_flags & O_ACCMODE) == O_RDONLY);
1235 	mutex_lock(&nvdimm_bus_list_mutex);
1236 	list_for_each_entry(nvdimm_bus, &nvdimm_bus_list, list) {
1237 		if (mode == DIMM_IOCTL) {
1238 			struct device *dev;
1239 
1240 			dev = device_find_child(&nvdimm_bus->dev,
1241 					file->private_data, match_dimm);
1242 			if (!dev)
1243 				continue;
1244 			nvdimm = to_nvdimm(dev);
1245 			found = nvdimm_bus;
1246 		} else if (nvdimm_bus->id == id) {
1247 			found = nvdimm_bus;
1248 		}
1249 
1250 		if (found) {
1251 			atomic_inc(&nvdimm_bus->ioctl_active);
1252 			break;
1253 		}
1254 	}
1255 	mutex_unlock(&nvdimm_bus_list_mutex);
1256 
1257 	if (!found)
1258 		return -ENXIO;
1259 
1260 	nvdimm_bus = found;
1261 	rc = __nd_ioctl(nvdimm_bus, nvdimm, ro, cmd, arg);
1262 
1263 	if (nvdimm)
1264 		put_device(&nvdimm->dev);
1265 	if (atomic_dec_and_test(&nvdimm_bus->ioctl_active))
1266 		wake_up(&nvdimm_bus->wait);
1267 
1268 	return rc;
1269 }
1270 
1271 static long bus_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1272 {
1273 	return nd_ioctl(file, cmd, arg, BUS_IOCTL);
1274 }
1275 
1276 static long dimm_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1277 {
1278 	return nd_ioctl(file, cmd, arg, DIMM_IOCTL);
1279 }
1280 
1281 static int nd_open(struct inode *inode, struct file *file)
1282 {
1283 	long minor = iminor(inode);
1284 
1285 	file->private_data = (void *) minor;
1286 	return 0;
1287 }
1288 
1289 static const struct file_operations nvdimm_bus_fops = {
1290 	.owner = THIS_MODULE,
1291 	.open = nd_open,
1292 	.unlocked_ioctl = bus_ioctl,
1293 	.compat_ioctl = compat_ptr_ioctl,
1294 	.llseek = noop_llseek,
1295 };
1296 
1297 static const struct file_operations nvdimm_fops = {
1298 	.owner = THIS_MODULE,
1299 	.open = nd_open,
1300 	.unlocked_ioctl = dimm_ioctl,
1301 	.compat_ioctl = compat_ptr_ioctl,
1302 	.llseek = noop_llseek,
1303 };
1304 
1305 int __init nvdimm_bus_init(void)
1306 {
1307 	int rc;
1308 
1309 	rc = bus_register(&nvdimm_bus_type);
1310 	if (rc)
1311 		return rc;
1312 
1313 	rc = register_chrdev(0, "ndctl", &nvdimm_bus_fops);
1314 	if (rc < 0)
1315 		goto err_bus_chrdev;
1316 	nvdimm_bus_major = rc;
1317 
1318 	rc = register_chrdev(0, "dimmctl", &nvdimm_fops);
1319 	if (rc < 0)
1320 		goto err_dimm_chrdev;
1321 	nvdimm_major = rc;
1322 
1323 	nd_class = class_create("nd");
1324 	if (IS_ERR(nd_class)) {
1325 		rc = PTR_ERR(nd_class);
1326 		goto err_class;
1327 	}
1328 
1329 	rc = driver_register(&nd_bus_driver.drv);
1330 	if (rc)
1331 		goto err_nd_bus;
1332 
1333 	return 0;
1334 
1335  err_nd_bus:
1336 	class_destroy(nd_class);
1337  err_class:
1338 	unregister_chrdev(nvdimm_major, "dimmctl");
1339  err_dimm_chrdev:
1340 	unregister_chrdev(nvdimm_bus_major, "ndctl");
1341  err_bus_chrdev:
1342 	bus_unregister(&nvdimm_bus_type);
1343 
1344 	return rc;
1345 }
1346 
1347 void nvdimm_bus_exit(void)
1348 {
1349 	driver_unregister(&nd_bus_driver.drv);
1350 	class_destroy(nd_class);
1351 	unregister_chrdev(nvdimm_bus_major, "ndctl");
1352 	unregister_chrdev(nvdimm_major, "dimmctl");
1353 	bus_unregister(&nvdimm_bus_type);
1354 	ida_destroy(&nd_ida);
1355 }
1356