xref: /linux/drivers/nvdimm/bus.c (revision c49731a04e7c14b2ccd146a7fddf92e78ccae143)
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 struct class *nd_class;
29 static DEFINE_IDA(nd_ida);
30 
31 static int to_nd_device_type(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(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 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_simple_remove(&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_simple_get(&nd_ida, 0, 0, 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 void nd_device_register(struct device *dev)
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 	async_schedule_dev_domain(nd_async_device_register, dev,
535 				  &nd_async_domain);
536 }
537 EXPORT_SYMBOL(nd_device_register);
538 
539 void nd_device_unregister(struct device *dev, enum nd_async_mode mode)
540 {
541 	bool killed;
542 
543 	switch (mode) {
544 	case ND_ASYNC:
545 		/*
546 		 * In the async case this is being triggered with the
547 		 * device lock held and the unregistration work needs to
548 		 * be moved out of line iff this is thread has won the
549 		 * race to schedule the deletion.
550 		 */
551 		if (!kill_device(dev))
552 			return;
553 
554 		get_device(dev);
555 		async_schedule_domain(nd_async_device_unregister, dev,
556 				&nd_async_domain);
557 		break;
558 	case ND_SYNC:
559 		/*
560 		 * In the sync case the device is being unregistered due
561 		 * to a state change of the parent. Claim the kill state
562 		 * to synchronize against other unregistration requests,
563 		 * or otherwise let the async path handle it if the
564 		 * unregistration was already queued.
565 		 */
566 		device_lock(dev);
567 		killed = kill_device(dev);
568 		device_unlock(dev);
569 
570 		if (!killed)
571 			return;
572 
573 		nd_synchronize();
574 		device_unregister(dev);
575 		break;
576 	}
577 }
578 EXPORT_SYMBOL(nd_device_unregister);
579 
580 /**
581  * __nd_driver_register() - register a region or a namespace driver
582  * @nd_drv: driver to register
583  * @owner: automatically set by nd_driver_register() macro
584  * @mod_name: automatically set by nd_driver_register() macro
585  */
586 int __nd_driver_register(struct nd_device_driver *nd_drv, struct module *owner,
587 		const char *mod_name)
588 {
589 	struct device_driver *drv = &nd_drv->drv;
590 
591 	if (!nd_drv->type) {
592 		pr_debug("driver type bitmask not set (%ps)\n",
593 				__builtin_return_address(0));
594 		return -EINVAL;
595 	}
596 
597 	if (!nd_drv->probe) {
598 		pr_debug("%s ->probe() must be specified\n", mod_name);
599 		return -EINVAL;
600 	}
601 
602 	drv->bus = &nvdimm_bus_type;
603 	drv->owner = owner;
604 	drv->mod_name = mod_name;
605 
606 	return driver_register(drv);
607 }
608 EXPORT_SYMBOL(__nd_driver_register);
609 
610 void nvdimm_check_and_set_ro(struct gendisk *disk)
611 {
612 	struct device *dev = disk_to_dev(disk)->parent;
613 	struct nd_region *nd_region = to_nd_region(dev->parent);
614 	int disk_ro = get_disk_ro(disk);
615 
616 	/* catch the disk up with the region ro state */
617 	if (disk_ro == nd_region->ro)
618 		return;
619 
620 	dev_info(dev, "%s read-%s, marking %s read-%s\n",
621 		 dev_name(&nd_region->dev), nd_region->ro ? "only" : "write",
622 		 disk->disk_name, nd_region->ro ? "only" : "write");
623 	set_disk_ro(disk, nd_region->ro);
624 }
625 EXPORT_SYMBOL(nvdimm_check_and_set_ro);
626 
627 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
628 		char *buf)
629 {
630 	return sprintf(buf, ND_DEVICE_MODALIAS_FMT "\n",
631 			to_nd_device_type(dev));
632 }
633 static DEVICE_ATTR_RO(modalias);
634 
635 static ssize_t devtype_show(struct device *dev, struct device_attribute *attr,
636 		char *buf)
637 {
638 	return sprintf(buf, "%s\n", dev->type->name);
639 }
640 static DEVICE_ATTR_RO(devtype);
641 
642 static struct attribute *nd_device_attributes[] = {
643 	&dev_attr_modalias.attr,
644 	&dev_attr_devtype.attr,
645 	NULL,
646 };
647 
648 /*
649  * nd_device_attribute_group - generic attributes for all devices on an nd bus
650  */
651 const struct attribute_group nd_device_attribute_group = {
652 	.attrs = nd_device_attributes,
653 };
654 
655 static ssize_t numa_node_show(struct device *dev,
656 		struct device_attribute *attr, char *buf)
657 {
658 	return sprintf(buf, "%d\n", dev_to_node(dev));
659 }
660 static DEVICE_ATTR_RO(numa_node);
661 
662 static int nvdimm_dev_to_target_node(struct device *dev)
663 {
664 	struct device *parent = dev->parent;
665 	struct nd_region *nd_region = NULL;
666 
667 	if (is_nd_region(dev))
668 		nd_region = to_nd_region(dev);
669 	else if (parent && is_nd_region(parent))
670 		nd_region = to_nd_region(parent);
671 
672 	if (!nd_region)
673 		return NUMA_NO_NODE;
674 	return nd_region->target_node;
675 }
676 
677 static ssize_t target_node_show(struct device *dev,
678 		struct device_attribute *attr, char *buf)
679 {
680 	return sprintf(buf, "%d\n", nvdimm_dev_to_target_node(dev));
681 }
682 static DEVICE_ATTR_RO(target_node);
683 
684 static struct attribute *nd_numa_attributes[] = {
685 	&dev_attr_numa_node.attr,
686 	&dev_attr_target_node.attr,
687 	NULL,
688 };
689 
690 static umode_t nd_numa_attr_visible(struct kobject *kobj, struct attribute *a,
691 		int n)
692 {
693 	struct device *dev = container_of(kobj, typeof(*dev), kobj);
694 
695 	if (!IS_ENABLED(CONFIG_NUMA))
696 		return 0;
697 
698 	if (a == &dev_attr_target_node.attr &&
699 			nvdimm_dev_to_target_node(dev) == NUMA_NO_NODE)
700 		return 0;
701 
702 	return a->mode;
703 }
704 
705 /*
706  * nd_numa_attribute_group - NUMA attributes for all devices on an nd bus
707  */
708 const struct attribute_group nd_numa_attribute_group = {
709 	.attrs = nd_numa_attributes,
710 	.is_visible = nd_numa_attr_visible,
711 };
712 
713 static void ndctl_release(struct device *dev)
714 {
715 	kfree(dev);
716 }
717 
718 static struct lock_class_key nvdimm_ndctl_key;
719 
720 int nvdimm_bus_create_ndctl(struct nvdimm_bus *nvdimm_bus)
721 {
722 	dev_t devt = MKDEV(nvdimm_bus_major, nvdimm_bus->id);
723 	struct device *dev;
724 	int rc;
725 
726 	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
727 	if (!dev)
728 		return -ENOMEM;
729 	device_initialize(dev);
730 	lockdep_set_class(&dev->mutex, &nvdimm_ndctl_key);
731 	device_set_pm_not_required(dev);
732 	dev->class = nd_class;
733 	dev->parent = &nvdimm_bus->dev;
734 	dev->devt = devt;
735 	dev->release = ndctl_release;
736 	rc = dev_set_name(dev, "ndctl%d", nvdimm_bus->id);
737 	if (rc)
738 		goto err;
739 
740 	rc = device_add(dev);
741 	if (rc) {
742 		dev_dbg(&nvdimm_bus->dev, "failed to register ndctl%d: %d\n",
743 				nvdimm_bus->id, rc);
744 		goto err;
745 	}
746 	return 0;
747 
748 err:
749 	put_device(dev);
750 	return rc;
751 }
752 
753 void nvdimm_bus_destroy_ndctl(struct nvdimm_bus *nvdimm_bus)
754 {
755 	device_destroy(nd_class, MKDEV(nvdimm_bus_major, nvdimm_bus->id));
756 }
757 
758 static const struct nd_cmd_desc __nd_cmd_dimm_descs[] = {
759 	[ND_CMD_IMPLEMENTED] = { },
760 	[ND_CMD_SMART] = {
761 		.out_num = 2,
762 		.out_sizes = { 4, 128, },
763 	},
764 	[ND_CMD_SMART_THRESHOLD] = {
765 		.out_num = 2,
766 		.out_sizes = { 4, 8, },
767 	},
768 	[ND_CMD_DIMM_FLAGS] = {
769 		.out_num = 2,
770 		.out_sizes = { 4, 4 },
771 	},
772 	[ND_CMD_GET_CONFIG_SIZE] = {
773 		.out_num = 3,
774 		.out_sizes = { 4, 4, 4, },
775 	},
776 	[ND_CMD_GET_CONFIG_DATA] = {
777 		.in_num = 2,
778 		.in_sizes = { 4, 4, },
779 		.out_num = 2,
780 		.out_sizes = { 4, UINT_MAX, },
781 	},
782 	[ND_CMD_SET_CONFIG_DATA] = {
783 		.in_num = 3,
784 		.in_sizes = { 4, 4, UINT_MAX, },
785 		.out_num = 1,
786 		.out_sizes = { 4, },
787 	},
788 	[ND_CMD_VENDOR] = {
789 		.in_num = 3,
790 		.in_sizes = { 4, 4, UINT_MAX, },
791 		.out_num = 3,
792 		.out_sizes = { 4, 4, UINT_MAX, },
793 	},
794 	[ND_CMD_CALL] = {
795 		.in_num = 2,
796 		.in_sizes = { sizeof(struct nd_cmd_pkg), UINT_MAX, },
797 		.out_num = 1,
798 		.out_sizes = { UINT_MAX, },
799 	},
800 };
801 
802 const struct nd_cmd_desc *nd_cmd_dimm_desc(int cmd)
803 {
804 	if (cmd < ARRAY_SIZE(__nd_cmd_dimm_descs))
805 		return &__nd_cmd_dimm_descs[cmd];
806 	return NULL;
807 }
808 EXPORT_SYMBOL_GPL(nd_cmd_dimm_desc);
809 
810 static const struct nd_cmd_desc __nd_cmd_bus_descs[] = {
811 	[ND_CMD_IMPLEMENTED] = { },
812 	[ND_CMD_ARS_CAP] = {
813 		.in_num = 2,
814 		.in_sizes = { 8, 8, },
815 		.out_num = 4,
816 		.out_sizes = { 4, 4, 4, 4, },
817 	},
818 	[ND_CMD_ARS_START] = {
819 		.in_num = 5,
820 		.in_sizes = { 8, 8, 2, 1, 5, },
821 		.out_num = 2,
822 		.out_sizes = { 4, 4, },
823 	},
824 	[ND_CMD_ARS_STATUS] = {
825 		.out_num = 3,
826 		.out_sizes = { 4, 4, UINT_MAX, },
827 	},
828 	[ND_CMD_CLEAR_ERROR] = {
829 		.in_num = 2,
830 		.in_sizes = { 8, 8, },
831 		.out_num = 3,
832 		.out_sizes = { 4, 4, 8, },
833 	},
834 	[ND_CMD_CALL] = {
835 		.in_num = 2,
836 		.in_sizes = { sizeof(struct nd_cmd_pkg), UINT_MAX, },
837 		.out_num = 1,
838 		.out_sizes = { UINT_MAX, },
839 	},
840 };
841 
842 const struct nd_cmd_desc *nd_cmd_bus_desc(int cmd)
843 {
844 	if (cmd < ARRAY_SIZE(__nd_cmd_bus_descs))
845 		return &__nd_cmd_bus_descs[cmd];
846 	return NULL;
847 }
848 EXPORT_SYMBOL_GPL(nd_cmd_bus_desc);
849 
850 u32 nd_cmd_in_size(struct nvdimm *nvdimm, int cmd,
851 		const struct nd_cmd_desc *desc, int idx, void *buf)
852 {
853 	if (idx >= desc->in_num)
854 		return UINT_MAX;
855 
856 	if (desc->in_sizes[idx] < UINT_MAX)
857 		return desc->in_sizes[idx];
858 
859 	if (nvdimm && cmd == ND_CMD_SET_CONFIG_DATA && idx == 2) {
860 		struct nd_cmd_set_config_hdr *hdr = buf;
861 
862 		return hdr->in_length;
863 	} else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2) {
864 		struct nd_cmd_vendor_hdr *hdr = buf;
865 
866 		return hdr->in_length;
867 	} else if (cmd == ND_CMD_CALL) {
868 		struct nd_cmd_pkg *pkg = buf;
869 
870 		return pkg->nd_size_in;
871 	}
872 
873 	return UINT_MAX;
874 }
875 EXPORT_SYMBOL_GPL(nd_cmd_in_size);
876 
877 u32 nd_cmd_out_size(struct nvdimm *nvdimm, int cmd,
878 		const struct nd_cmd_desc *desc, int idx, const u32 *in_field,
879 		const u32 *out_field, unsigned long remainder)
880 {
881 	if (idx >= desc->out_num)
882 		return UINT_MAX;
883 
884 	if (desc->out_sizes[idx] < UINT_MAX)
885 		return desc->out_sizes[idx];
886 
887 	if (nvdimm && cmd == ND_CMD_GET_CONFIG_DATA && idx == 1)
888 		return in_field[1];
889 	else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2)
890 		return out_field[1];
891 	else if (!nvdimm && cmd == ND_CMD_ARS_STATUS && idx == 2) {
892 		/*
893 		 * Per table 9-276 ARS Data in ACPI 6.1, out_field[1] is
894 		 * "Size of Output Buffer in bytes, including this
895 		 * field."
896 		 */
897 		if (out_field[1] < 4)
898 			return 0;
899 		/*
900 		 * ACPI 6.1 is ambiguous if 'status' is included in the
901 		 * output size. If we encounter an output size that
902 		 * overshoots the remainder by 4 bytes, assume it was
903 		 * including 'status'.
904 		 */
905 		if (out_field[1] - 4 == remainder)
906 			return remainder;
907 		return out_field[1] - 8;
908 	} else if (cmd == ND_CMD_CALL) {
909 		struct nd_cmd_pkg *pkg = (struct nd_cmd_pkg *) in_field;
910 
911 		return pkg->nd_size_out;
912 	}
913 
914 
915 	return UINT_MAX;
916 }
917 EXPORT_SYMBOL_GPL(nd_cmd_out_size);
918 
919 void wait_nvdimm_bus_probe_idle(struct device *dev)
920 {
921 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
922 
923 	do {
924 		if (nvdimm_bus->probe_active == 0)
925 			break;
926 		nvdimm_bus_unlock(dev);
927 		device_unlock(dev);
928 		wait_event(nvdimm_bus->wait,
929 				nvdimm_bus->probe_active == 0);
930 		device_lock(dev);
931 		nvdimm_bus_lock(dev);
932 	} while (true);
933 }
934 
935 static int nd_pmem_forget_poison_check(struct device *dev, void *data)
936 {
937 	struct nd_cmd_clear_error *clear_err =
938 		(struct nd_cmd_clear_error *)data;
939 	struct nd_btt *nd_btt = is_nd_btt(dev) ? to_nd_btt(dev) : NULL;
940 	struct nd_pfn *nd_pfn = is_nd_pfn(dev) ? to_nd_pfn(dev) : NULL;
941 	struct nd_dax *nd_dax = is_nd_dax(dev) ? to_nd_dax(dev) : NULL;
942 	struct nd_namespace_common *ndns = NULL;
943 	struct nd_namespace_io *nsio;
944 	resource_size_t offset = 0, end_trunc = 0, start, end, pstart, pend;
945 
946 	if (nd_dax || !dev->driver)
947 		return 0;
948 
949 	start = clear_err->address;
950 	end = clear_err->address + clear_err->cleared - 1;
951 
952 	if (nd_btt || nd_pfn || nd_dax) {
953 		if (nd_btt)
954 			ndns = nd_btt->ndns;
955 		else if (nd_pfn)
956 			ndns = nd_pfn->ndns;
957 		else if (nd_dax)
958 			ndns = nd_dax->nd_pfn.ndns;
959 
960 		if (!ndns)
961 			return 0;
962 	} else
963 		ndns = to_ndns(dev);
964 
965 	nsio = to_nd_namespace_io(&ndns->dev);
966 	pstart = nsio->res.start + offset;
967 	pend = nsio->res.end - end_trunc;
968 
969 	if ((pstart >= start) && (pend <= end))
970 		return -EBUSY;
971 
972 	return 0;
973 
974 }
975 
976 static int nd_ns_forget_poison_check(struct device *dev, void *data)
977 {
978 	return device_for_each_child(dev, data, nd_pmem_forget_poison_check);
979 }
980 
981 /* set_config requires an idle interleave set */
982 static int nd_cmd_clear_to_send(struct nvdimm_bus *nvdimm_bus,
983 		struct nvdimm *nvdimm, unsigned int cmd, void *data)
984 {
985 	struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
986 
987 	/* ask the bus provider if it would like to block this request */
988 	if (nd_desc->clear_to_send) {
989 		int rc = nd_desc->clear_to_send(nd_desc, nvdimm, cmd, data);
990 
991 		if (rc)
992 			return rc;
993 	}
994 
995 	/* require clear error to go through the pmem driver */
996 	if (!nvdimm && cmd == ND_CMD_CLEAR_ERROR)
997 		return device_for_each_child(&nvdimm_bus->dev, data,
998 				nd_ns_forget_poison_check);
999 
1000 	if (!nvdimm || cmd != ND_CMD_SET_CONFIG_DATA)
1001 		return 0;
1002 
1003 	/* prevent label manipulation while the kernel owns label updates */
1004 	wait_nvdimm_bus_probe_idle(&nvdimm_bus->dev);
1005 	if (atomic_read(&nvdimm->busy))
1006 		return -EBUSY;
1007 	return 0;
1008 }
1009 
1010 static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm,
1011 		int read_only, unsigned int ioctl_cmd, unsigned long arg)
1012 {
1013 	struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
1014 	const struct nd_cmd_desc *desc = NULL;
1015 	unsigned int cmd = _IOC_NR(ioctl_cmd);
1016 	struct device *dev = &nvdimm_bus->dev;
1017 	void __user *p = (void __user *) arg;
1018 	char *out_env = NULL, *in_env = NULL;
1019 	const char *cmd_name, *dimm_name;
1020 	u32 in_len = 0, out_len = 0;
1021 	unsigned int func = cmd;
1022 	unsigned long cmd_mask;
1023 	struct nd_cmd_pkg pkg;
1024 	int rc, i, cmd_rc;
1025 	void *buf = NULL;
1026 	u64 buf_len = 0;
1027 
1028 	if (nvdimm) {
1029 		desc = nd_cmd_dimm_desc(cmd);
1030 		cmd_name = nvdimm_cmd_name(cmd);
1031 		cmd_mask = nvdimm->cmd_mask;
1032 		dimm_name = dev_name(&nvdimm->dev);
1033 	} else {
1034 		desc = nd_cmd_bus_desc(cmd);
1035 		cmd_name = nvdimm_bus_cmd_name(cmd);
1036 		cmd_mask = nd_desc->cmd_mask;
1037 		dimm_name = "bus";
1038 	}
1039 
1040 	/* Validate command family support against bus declared support */
1041 	if (cmd == ND_CMD_CALL) {
1042 		unsigned long *mask;
1043 
1044 		if (copy_from_user(&pkg, p, sizeof(pkg)))
1045 			return -EFAULT;
1046 
1047 		if (nvdimm) {
1048 			if (pkg.nd_family > NVDIMM_FAMILY_MAX)
1049 				return -EINVAL;
1050 			mask = &nd_desc->dimm_family_mask;
1051 		} else {
1052 			if (pkg.nd_family > NVDIMM_BUS_FAMILY_MAX)
1053 				return -EINVAL;
1054 			mask = &nd_desc->bus_family_mask;
1055 		}
1056 
1057 		if (!test_bit(pkg.nd_family, mask))
1058 			return -EINVAL;
1059 	}
1060 
1061 	if (!desc ||
1062 	    (desc->out_num + desc->in_num == 0) ||
1063 	    cmd > ND_CMD_CALL ||
1064 	    !test_bit(cmd, &cmd_mask))
1065 		return -ENOTTY;
1066 
1067 	/* fail write commands (when read-only) */
1068 	if (read_only)
1069 		switch (cmd) {
1070 		case ND_CMD_VENDOR:
1071 		case ND_CMD_SET_CONFIG_DATA:
1072 		case ND_CMD_ARS_START:
1073 		case ND_CMD_CLEAR_ERROR:
1074 		case ND_CMD_CALL:
1075 			dev_dbg(dev, "'%s' command while read-only.\n",
1076 					nvdimm ? nvdimm_cmd_name(cmd)
1077 					: nvdimm_bus_cmd_name(cmd));
1078 			return -EPERM;
1079 		default:
1080 			break;
1081 		}
1082 
1083 	/* process an input envelope */
1084 	in_env = kzalloc(ND_CMD_MAX_ENVELOPE, GFP_KERNEL);
1085 	if (!in_env)
1086 		return -ENOMEM;
1087 	for (i = 0; i < desc->in_num; i++) {
1088 		u32 in_size, copy;
1089 
1090 		in_size = nd_cmd_in_size(nvdimm, cmd, desc, i, in_env);
1091 		if (in_size == UINT_MAX) {
1092 			dev_err(dev, "%s:%s unknown input size cmd: %s field: %d\n",
1093 					__func__, dimm_name, cmd_name, i);
1094 			rc = -ENXIO;
1095 			goto out;
1096 		}
1097 		if (in_len < ND_CMD_MAX_ENVELOPE)
1098 			copy = min_t(u32, ND_CMD_MAX_ENVELOPE - in_len, in_size);
1099 		else
1100 			copy = 0;
1101 		if (copy && copy_from_user(&in_env[in_len], p + in_len, copy)) {
1102 			rc = -EFAULT;
1103 			goto out;
1104 		}
1105 		in_len += in_size;
1106 	}
1107 
1108 	if (cmd == ND_CMD_CALL) {
1109 		func = pkg.nd_command;
1110 		dev_dbg(dev, "%s, idx: %llu, in: %u, out: %u, len %llu\n",
1111 				dimm_name, pkg.nd_command,
1112 				in_len, out_len, buf_len);
1113 	}
1114 
1115 	/* process an output envelope */
1116 	out_env = kzalloc(ND_CMD_MAX_ENVELOPE, GFP_KERNEL);
1117 	if (!out_env) {
1118 		rc = -ENOMEM;
1119 		goto out;
1120 	}
1121 
1122 	for (i = 0; i < desc->out_num; i++) {
1123 		u32 out_size = nd_cmd_out_size(nvdimm, cmd, desc, i,
1124 				(u32 *) in_env, (u32 *) out_env, 0);
1125 		u32 copy;
1126 
1127 		if (out_size == UINT_MAX) {
1128 			dev_dbg(dev, "%s unknown output size cmd: %s field: %d\n",
1129 					dimm_name, cmd_name, i);
1130 			rc = -EFAULT;
1131 			goto out;
1132 		}
1133 		if (out_len < ND_CMD_MAX_ENVELOPE)
1134 			copy = min_t(u32, ND_CMD_MAX_ENVELOPE - out_len, out_size);
1135 		else
1136 			copy = 0;
1137 		if (copy && copy_from_user(&out_env[out_len],
1138 					p + in_len + out_len, copy)) {
1139 			rc = -EFAULT;
1140 			goto out;
1141 		}
1142 		out_len += out_size;
1143 	}
1144 
1145 	buf_len = (u64) out_len + (u64) in_len;
1146 	if (buf_len > ND_IOCTL_MAX_BUFLEN) {
1147 		dev_dbg(dev, "%s cmd: %s buf_len: %llu > %d\n", dimm_name,
1148 				cmd_name, buf_len, ND_IOCTL_MAX_BUFLEN);
1149 		rc = -EINVAL;
1150 		goto out;
1151 	}
1152 
1153 	buf = vmalloc(buf_len);
1154 	if (!buf) {
1155 		rc = -ENOMEM;
1156 		goto out;
1157 	}
1158 
1159 	if (copy_from_user(buf, p, buf_len)) {
1160 		rc = -EFAULT;
1161 		goto out;
1162 	}
1163 
1164 	device_lock(dev);
1165 	nvdimm_bus_lock(dev);
1166 	rc = nd_cmd_clear_to_send(nvdimm_bus, nvdimm, func, buf);
1167 	if (rc)
1168 		goto out_unlock;
1169 
1170 	rc = nd_desc->ndctl(nd_desc, nvdimm, cmd, buf, buf_len, &cmd_rc);
1171 	if (rc < 0)
1172 		goto out_unlock;
1173 
1174 	if (!nvdimm && cmd == ND_CMD_CLEAR_ERROR && cmd_rc >= 0) {
1175 		struct nd_cmd_clear_error *clear_err = buf;
1176 
1177 		nvdimm_account_cleared_poison(nvdimm_bus, clear_err->address,
1178 				clear_err->cleared);
1179 	}
1180 
1181 	if (copy_to_user(p, buf, buf_len))
1182 		rc = -EFAULT;
1183 
1184 out_unlock:
1185 	nvdimm_bus_unlock(dev);
1186 	device_unlock(dev);
1187 out:
1188 	kfree(in_env);
1189 	kfree(out_env);
1190 	vfree(buf);
1191 	return rc;
1192 }
1193 
1194 enum nd_ioctl_mode {
1195 	BUS_IOCTL,
1196 	DIMM_IOCTL,
1197 };
1198 
1199 static int match_dimm(struct device *dev, void *data)
1200 {
1201 	long id = (long) data;
1202 
1203 	if (is_nvdimm(dev)) {
1204 		struct nvdimm *nvdimm = to_nvdimm(dev);
1205 
1206 		return nvdimm->id == id;
1207 	}
1208 
1209 	return 0;
1210 }
1211 
1212 static long nd_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
1213 		enum nd_ioctl_mode mode)
1214 
1215 {
1216 	struct nvdimm_bus *nvdimm_bus, *found = NULL;
1217 	long id = (long) file->private_data;
1218 	struct nvdimm *nvdimm = NULL;
1219 	int rc, ro;
1220 
1221 	ro = ((file->f_flags & O_ACCMODE) == O_RDONLY);
1222 	mutex_lock(&nvdimm_bus_list_mutex);
1223 	list_for_each_entry(nvdimm_bus, &nvdimm_bus_list, list) {
1224 		if (mode == DIMM_IOCTL) {
1225 			struct device *dev;
1226 
1227 			dev = device_find_child(&nvdimm_bus->dev,
1228 					file->private_data, match_dimm);
1229 			if (!dev)
1230 				continue;
1231 			nvdimm = to_nvdimm(dev);
1232 			found = nvdimm_bus;
1233 		} else if (nvdimm_bus->id == id) {
1234 			found = nvdimm_bus;
1235 		}
1236 
1237 		if (found) {
1238 			atomic_inc(&nvdimm_bus->ioctl_active);
1239 			break;
1240 		}
1241 	}
1242 	mutex_unlock(&nvdimm_bus_list_mutex);
1243 
1244 	if (!found)
1245 		return -ENXIO;
1246 
1247 	nvdimm_bus = found;
1248 	rc = __nd_ioctl(nvdimm_bus, nvdimm, ro, cmd, arg);
1249 
1250 	if (nvdimm)
1251 		put_device(&nvdimm->dev);
1252 	if (atomic_dec_and_test(&nvdimm_bus->ioctl_active))
1253 		wake_up(&nvdimm_bus->wait);
1254 
1255 	return rc;
1256 }
1257 
1258 static long bus_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1259 {
1260 	return nd_ioctl(file, cmd, arg, BUS_IOCTL);
1261 }
1262 
1263 static long dimm_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1264 {
1265 	return nd_ioctl(file, cmd, arg, DIMM_IOCTL);
1266 }
1267 
1268 static int nd_open(struct inode *inode, struct file *file)
1269 {
1270 	long minor = iminor(inode);
1271 
1272 	file->private_data = (void *) minor;
1273 	return 0;
1274 }
1275 
1276 static const struct file_operations nvdimm_bus_fops = {
1277 	.owner = THIS_MODULE,
1278 	.open = nd_open,
1279 	.unlocked_ioctl = bus_ioctl,
1280 	.compat_ioctl = compat_ptr_ioctl,
1281 	.llseek = noop_llseek,
1282 };
1283 
1284 static const struct file_operations nvdimm_fops = {
1285 	.owner = THIS_MODULE,
1286 	.open = nd_open,
1287 	.unlocked_ioctl = dimm_ioctl,
1288 	.compat_ioctl = compat_ptr_ioctl,
1289 	.llseek = noop_llseek,
1290 };
1291 
1292 int __init nvdimm_bus_init(void)
1293 {
1294 	int rc;
1295 
1296 	rc = bus_register(&nvdimm_bus_type);
1297 	if (rc)
1298 		return rc;
1299 
1300 	rc = register_chrdev(0, "ndctl", &nvdimm_bus_fops);
1301 	if (rc < 0)
1302 		goto err_bus_chrdev;
1303 	nvdimm_bus_major = rc;
1304 
1305 	rc = register_chrdev(0, "dimmctl", &nvdimm_fops);
1306 	if (rc < 0)
1307 		goto err_dimm_chrdev;
1308 	nvdimm_major = rc;
1309 
1310 	nd_class = class_create(THIS_MODULE, "nd");
1311 	if (IS_ERR(nd_class)) {
1312 		rc = PTR_ERR(nd_class);
1313 		goto err_class;
1314 	}
1315 
1316 	rc = driver_register(&nd_bus_driver.drv);
1317 	if (rc)
1318 		goto err_nd_bus;
1319 
1320 	return 0;
1321 
1322  err_nd_bus:
1323 	class_destroy(nd_class);
1324  err_class:
1325 	unregister_chrdev(nvdimm_major, "dimmctl");
1326  err_dimm_chrdev:
1327 	unregister_chrdev(nvdimm_bus_major, "ndctl");
1328  err_bus_chrdev:
1329 	bus_unregister(&nvdimm_bus_type);
1330 
1331 	return rc;
1332 }
1333 
1334 void nvdimm_bus_exit(void)
1335 {
1336 	driver_unregister(&nd_bus_driver.drv);
1337 	class_destroy(nd_class);
1338 	unregister_chrdev(nvdimm_bus_major, "ndctl");
1339 	unregister_chrdev(nvdimm_major, "dimmctl");
1340 	bus_unregister(&nvdimm_bus_type);
1341 	ida_destroy(&nd_ida);
1342 }
1343