Merge branch '5.20/scsi-queue' into 6.0/scsi-fixes
[platform/kernel/linux-starfive.git] / drivers / nvdimm / bus.c
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 }