Merge drm/drm-next into drm-misc-next
[linux-2.6-microblaze.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/genhd.h>
15 #include <linux/ndctl.h>
16 #include <linux/sched.h>
17 #include <linux/slab.h>
18 #include <linux/cpu.h>
19 #include <linux/fs.h>
20 #include <linux/io.h>
21 #include <linux/mm.h>
22 #include <linux/nd.h>
23 #include "nd-core.h"
24 #include "nd.h"
25 #include "pfn.h"
26
27 int nvdimm_major;
28 static int nvdimm_bus_major;
29 struct class *nd_class;
30 static DEFINE_IDA(nd_ida);
31
32 static int to_nd_device_type(struct device *dev)
33 {
34         if (is_nvdimm(dev))
35                 return ND_DEVICE_DIMM;
36         else if (is_memory(dev))
37                 return ND_DEVICE_REGION_PMEM;
38         else if (is_nd_blk(dev))
39                 return ND_DEVICE_REGION_BLK;
40         else if (is_nd_dax(dev))
41                 return ND_DEVICE_DAX_PMEM;
42         else if (is_nd_region(dev->parent))
43                 return nd_region_to_nstype(to_nd_region(dev->parent));
44
45         return 0;
46 }
47
48 static int nvdimm_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
49 {
50         return add_uevent_var(env, "MODALIAS=" ND_DEVICE_MODALIAS_FMT,
51                         to_nd_device_type(dev));
52 }
53
54 static struct module *to_bus_provider(struct device *dev)
55 {
56         /* pin bus providers while regions are enabled */
57         if (is_nd_region(dev)) {
58                 struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
59
60                 return nvdimm_bus->nd_desc->module;
61         }
62         return NULL;
63 }
64
65 static void nvdimm_bus_probe_start(struct nvdimm_bus *nvdimm_bus)
66 {
67         nvdimm_bus_lock(&nvdimm_bus->dev);
68         nvdimm_bus->probe_active++;
69         nvdimm_bus_unlock(&nvdimm_bus->dev);
70 }
71
72 static void nvdimm_bus_probe_end(struct nvdimm_bus *nvdimm_bus)
73 {
74         nvdimm_bus_lock(&nvdimm_bus->dev);
75         if (--nvdimm_bus->probe_active == 0)
76                 wake_up(&nvdimm_bus->wait);
77         nvdimm_bus_unlock(&nvdimm_bus->dev);
78 }
79
80 static int nvdimm_bus_probe(struct device *dev)
81 {
82         struct nd_device_driver *nd_drv = to_nd_device_driver(dev->driver);
83         struct module *provider = to_bus_provider(dev);
84         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
85         int rc;
86
87         if (!try_module_get(provider))
88                 return -ENXIO;
89
90         dev_dbg(&nvdimm_bus->dev, "START: %s.probe(%s)\n",
91                         dev->driver->name, dev_name(dev));
92
93         nvdimm_bus_probe_start(nvdimm_bus);
94         debug_nvdimm_lock(dev);
95         rc = nd_drv->probe(dev);
96         debug_nvdimm_unlock(dev);
97
98         if ((rc == 0 || rc == -EOPNOTSUPP) &&
99                         dev->parent && is_nd_region(dev->parent))
100                 nd_region_advance_seeds(to_nd_region(dev->parent), dev);
101         nvdimm_bus_probe_end(nvdimm_bus);
102
103         dev_dbg(&nvdimm_bus->dev, "END: %s.probe(%s) = %d\n", dev->driver->name,
104                         dev_name(dev), rc);
105
106         if (rc != 0)
107                 module_put(provider);
108         return rc;
109 }
110
111 static int nvdimm_bus_remove(struct device *dev)
112 {
113         struct nd_device_driver *nd_drv = to_nd_device_driver(dev->driver);
114         struct module *provider = to_bus_provider(dev);
115         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
116         int rc = 0;
117
118         if (nd_drv->remove) {
119                 debug_nvdimm_lock(dev);
120                 rc = nd_drv->remove(dev);
121                 debug_nvdimm_unlock(dev);
122         }
123
124         dev_dbg(&nvdimm_bus->dev, "%s.remove(%s) = %d\n", dev->driver->name,
125                         dev_name(dev), rc);
126         module_put(provider);
127         return rc;
128 }
129
130 static void nvdimm_bus_shutdown(struct device *dev)
131 {
132         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
133         struct nd_device_driver *nd_drv = NULL;
134
135         if (dev->driver)
136                 nd_drv = to_nd_device_driver(dev->driver);
137
138         if (nd_drv && nd_drv->shutdown) {
139                 nd_drv->shutdown(dev);
140                 dev_dbg(&nvdimm_bus->dev, "%s.shutdown(%s)\n",
141                                 dev->driver->name, dev_name(dev));
142         }
143 }
144
145 void nd_device_notify(struct device *dev, enum nvdimm_event event)
146 {
147         nd_device_lock(dev);
148         if (dev->driver) {
149                 struct nd_device_driver *nd_drv;
150
151                 nd_drv = to_nd_device_driver(dev->driver);
152                 if (nd_drv->notify)
153                         nd_drv->notify(dev, event);
154         }
155         nd_device_unlock(dev);
156 }
157 EXPORT_SYMBOL(nd_device_notify);
158
159 void nvdimm_region_notify(struct nd_region *nd_region, enum nvdimm_event event)
160 {
161         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&nd_region->dev);
162
163         if (!nvdimm_bus)
164                 return;
165
166         /* caller is responsible for holding a reference on the device */
167         nd_device_notify(&nd_region->dev, event);
168 }
169 EXPORT_SYMBOL_GPL(nvdimm_region_notify);
170
171 struct clear_badblocks_context {
172         resource_size_t phys, cleared;
173 };
174
175 static int nvdimm_clear_badblocks_region(struct device *dev, void *data)
176 {
177         struct clear_badblocks_context *ctx = data;
178         struct nd_region *nd_region;
179         resource_size_t ndr_end;
180         sector_t sector;
181
182         /* make sure device is a region */
183         if (!is_memory(dev))
184                 return 0;
185
186         nd_region = to_nd_region(dev);
187         ndr_end = nd_region->ndr_start + nd_region->ndr_size - 1;
188
189         /* make sure we are in the region */
190         if (ctx->phys < nd_region->ndr_start
191                         || (ctx->phys + ctx->cleared) > ndr_end)
192                 return 0;
193
194         sector = (ctx->phys - nd_region->ndr_start) / 512;
195         badblocks_clear(&nd_region->bb, sector, ctx->cleared / 512);
196
197         if (nd_region->bb_state)
198                 sysfs_notify_dirent(nd_region->bb_state);
199
200         return 0;
201 }
202
203 static void nvdimm_clear_badblocks_regions(struct nvdimm_bus *nvdimm_bus,
204                 phys_addr_t phys, u64 cleared)
205 {
206         struct clear_badblocks_context ctx = {
207                 .phys = phys,
208                 .cleared = cleared,
209         };
210
211         device_for_each_child(&nvdimm_bus->dev, &ctx,
212                         nvdimm_clear_badblocks_region);
213 }
214
215 static void nvdimm_account_cleared_poison(struct nvdimm_bus *nvdimm_bus,
216                 phys_addr_t phys, u64 cleared)
217 {
218         if (cleared > 0)
219                 badrange_forget(&nvdimm_bus->badrange, phys, cleared);
220
221         if (cleared > 0 && cleared / 512)
222                 nvdimm_clear_badblocks_regions(nvdimm_bus, phys, cleared);
223 }
224
225 long nvdimm_clear_poison(struct device *dev, phys_addr_t phys,
226                 unsigned int len)
227 {
228         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
229         struct nvdimm_bus_descriptor *nd_desc;
230         struct nd_cmd_clear_error clear_err;
231         struct nd_cmd_ars_cap ars_cap;
232         u32 clear_err_unit, mask;
233         unsigned int noio_flag;
234         int cmd_rc, rc;
235
236         if (!nvdimm_bus)
237                 return -ENXIO;
238
239         nd_desc = nvdimm_bus->nd_desc;
240         /*
241          * if ndctl does not exist, it's PMEM_LEGACY and
242          * we want to just pretend everything is handled.
243          */
244         if (!nd_desc->ndctl)
245                 return len;
246
247         memset(&ars_cap, 0, sizeof(ars_cap));
248         ars_cap.address = phys;
249         ars_cap.length = len;
250         noio_flag = memalloc_noio_save();
251         rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_ARS_CAP, &ars_cap,
252                         sizeof(ars_cap), &cmd_rc);
253         memalloc_noio_restore(noio_flag);
254         if (rc < 0)
255                 return rc;
256         if (cmd_rc < 0)
257                 return cmd_rc;
258         clear_err_unit = ars_cap.clear_err_unit;
259         if (!clear_err_unit || !is_power_of_2(clear_err_unit))
260                 return -ENXIO;
261
262         mask = clear_err_unit - 1;
263         if ((phys | len) & mask)
264                 return -ENXIO;
265         memset(&clear_err, 0, sizeof(clear_err));
266         clear_err.address = phys;
267         clear_err.length = len;
268         noio_flag = memalloc_noio_save();
269         rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_CLEAR_ERROR, &clear_err,
270                         sizeof(clear_err), &cmd_rc);
271         memalloc_noio_restore(noio_flag);
272         if (rc < 0)
273                 return rc;
274         if (cmd_rc < 0)
275                 return cmd_rc;
276
277         nvdimm_account_cleared_poison(nvdimm_bus, phys, clear_err.cleared);
278
279         return clear_err.cleared;
280 }
281 EXPORT_SYMBOL_GPL(nvdimm_clear_poison);
282
283 static int nvdimm_bus_match(struct device *dev, struct device_driver *drv);
284
285 static struct bus_type nvdimm_bus_type = {
286         .name = "nd",
287         .uevent = nvdimm_bus_uevent,
288         .match = nvdimm_bus_match,
289         .probe = nvdimm_bus_probe,
290         .remove = nvdimm_bus_remove,
291         .shutdown = nvdimm_bus_shutdown,
292 };
293
294 static void nvdimm_bus_release(struct device *dev)
295 {
296         struct nvdimm_bus *nvdimm_bus;
297
298         nvdimm_bus = container_of(dev, struct nvdimm_bus, dev);
299         ida_simple_remove(&nd_ida, nvdimm_bus->id);
300         kfree(nvdimm_bus);
301 }
302
303 static const struct device_type nvdimm_bus_dev_type = {
304         .release = nvdimm_bus_release,
305         .groups = nvdimm_bus_attribute_groups,
306 };
307
308 bool is_nvdimm_bus(struct device *dev)
309 {
310         return dev->type == &nvdimm_bus_dev_type;
311 }
312
313 struct nvdimm_bus *walk_to_nvdimm_bus(struct device *nd_dev)
314 {
315         struct device *dev;
316
317         for (dev = nd_dev; dev; dev = dev->parent)
318                 if (is_nvdimm_bus(dev))
319                         break;
320         dev_WARN_ONCE(nd_dev, !dev, "invalid dev, not on nd bus\n");
321         if (dev)
322                 return to_nvdimm_bus(dev);
323         return NULL;
324 }
325
326 struct nvdimm_bus *to_nvdimm_bus(struct device *dev)
327 {
328         struct nvdimm_bus *nvdimm_bus;
329
330         nvdimm_bus = container_of(dev, struct nvdimm_bus, dev);
331         WARN_ON(!is_nvdimm_bus(dev));
332         return nvdimm_bus;
333 }
334 EXPORT_SYMBOL_GPL(to_nvdimm_bus);
335
336 struct nvdimm_bus *nvdimm_to_bus(struct nvdimm *nvdimm)
337 {
338         return to_nvdimm_bus(nvdimm->dev.parent);
339 }
340 EXPORT_SYMBOL_GPL(nvdimm_to_bus);
341
342 struct nvdimm_bus *nvdimm_bus_register(struct device *parent,
343                 struct nvdimm_bus_descriptor *nd_desc)
344 {
345         struct nvdimm_bus *nvdimm_bus;
346         int rc;
347
348         nvdimm_bus = kzalloc(sizeof(*nvdimm_bus), GFP_KERNEL);
349         if (!nvdimm_bus)
350                 return NULL;
351         INIT_LIST_HEAD(&nvdimm_bus->list);
352         INIT_LIST_HEAD(&nvdimm_bus->mapping_list);
353         init_waitqueue_head(&nvdimm_bus->wait);
354         nvdimm_bus->id = ida_simple_get(&nd_ida, 0, 0, GFP_KERNEL);
355         if (nvdimm_bus->id < 0) {
356                 kfree(nvdimm_bus);
357                 return NULL;
358         }
359         mutex_init(&nvdimm_bus->reconfig_mutex);
360         badrange_init(&nvdimm_bus->badrange);
361         nvdimm_bus->nd_desc = nd_desc;
362         nvdimm_bus->dev.parent = parent;
363         nvdimm_bus->dev.type = &nvdimm_bus_dev_type;
364         nvdimm_bus->dev.groups = nd_desc->attr_groups;
365         nvdimm_bus->dev.bus = &nvdimm_bus_type;
366         nvdimm_bus->dev.of_node = nd_desc->of_node;
367         dev_set_name(&nvdimm_bus->dev, "ndbus%d", nvdimm_bus->id);
368         rc = device_register(&nvdimm_bus->dev);
369         if (rc) {
370                 dev_dbg(&nvdimm_bus->dev, "registration failed: %d\n", rc);
371                 goto err;
372         }
373
374         return nvdimm_bus;
375  err:
376         put_device(&nvdimm_bus->dev);
377         return NULL;
378 }
379 EXPORT_SYMBOL_GPL(nvdimm_bus_register);
380
381 void nvdimm_bus_unregister(struct nvdimm_bus *nvdimm_bus)
382 {
383         if (!nvdimm_bus)
384                 return;
385         device_unregister(&nvdimm_bus->dev);
386 }
387 EXPORT_SYMBOL_GPL(nvdimm_bus_unregister);
388
389 static int child_unregister(struct device *dev, void *data)
390 {
391         /*
392          * the singular ndctl class device per bus needs to be
393          * "device_destroy"ed, so skip it here
394          *
395          * i.e. remove classless children
396          */
397         if (dev->class)
398                 return 0;
399
400         if (is_nvdimm(dev)) {
401                 struct nvdimm *nvdimm = to_nvdimm(dev);
402                 bool dev_put = false;
403
404                 /* We are shutting down. Make state frozen artificially. */
405                 nvdimm_bus_lock(dev);
406                 set_bit(NVDIMM_SECURITY_FROZEN, &nvdimm->sec.flags);
407                 if (test_and_clear_bit(NDD_WORK_PENDING, &nvdimm->flags))
408                         dev_put = true;
409                 nvdimm_bus_unlock(dev);
410                 cancel_delayed_work_sync(&nvdimm->dwork);
411                 if (dev_put)
412                         put_device(dev);
413         }
414         nd_device_unregister(dev, ND_SYNC);
415
416         return 0;
417 }
418
419 static void free_badrange_list(struct list_head *badrange_list)
420 {
421         struct badrange_entry *bre, *next;
422
423         list_for_each_entry_safe(bre, next, badrange_list, list) {
424                 list_del(&bre->list);
425                 kfree(bre);
426         }
427         list_del_init(badrange_list);
428 }
429
430 static int nd_bus_remove(struct device *dev)
431 {
432         struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
433
434         mutex_lock(&nvdimm_bus_list_mutex);
435         list_del_init(&nvdimm_bus->list);
436         mutex_unlock(&nvdimm_bus_list_mutex);
437
438         wait_event(nvdimm_bus->wait,
439                         atomic_read(&nvdimm_bus->ioctl_active) == 0);
440
441         nd_synchronize();
442         device_for_each_child(&nvdimm_bus->dev, NULL, child_unregister);
443
444         spin_lock(&nvdimm_bus->badrange.lock);
445         free_badrange_list(&nvdimm_bus->badrange.list);
446         spin_unlock(&nvdimm_bus->badrange.lock);
447
448         nvdimm_bus_destroy_ndctl(nvdimm_bus);
449
450         return 0;
451 }
452
453 static int nd_bus_probe(struct device *dev)
454 {
455         struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
456         int rc;
457
458         rc = nvdimm_bus_create_ndctl(nvdimm_bus);
459         if (rc)
460                 return rc;
461
462         mutex_lock(&nvdimm_bus_list_mutex);
463         list_add_tail(&nvdimm_bus->list, &nvdimm_bus_list);
464         mutex_unlock(&nvdimm_bus_list_mutex);
465
466         /* enable bus provider attributes to look up their local context */
467         dev_set_drvdata(dev, nvdimm_bus->nd_desc);
468
469         return 0;
470 }
471
472 static struct nd_device_driver nd_bus_driver = {
473         .probe = nd_bus_probe,
474         .remove = nd_bus_remove,
475         .drv = {
476                 .name = "nd_bus",
477                 .suppress_bind_attrs = true,
478                 .bus = &nvdimm_bus_type,
479                 .owner = THIS_MODULE,
480                 .mod_name = KBUILD_MODNAME,
481         },
482 };
483
484 static int nvdimm_bus_match(struct device *dev, struct device_driver *drv)
485 {
486         struct nd_device_driver *nd_drv = to_nd_device_driver(drv);
487
488         if (is_nvdimm_bus(dev) && nd_drv == &nd_bus_driver)
489                 return true;
490
491         return !!test_bit(to_nd_device_type(dev), &nd_drv->type);
492 }
493
494 static ASYNC_DOMAIN_EXCLUSIVE(nd_async_domain);
495
496 void nd_synchronize(void)
497 {
498         async_synchronize_full_domain(&nd_async_domain);
499 }
500 EXPORT_SYMBOL_GPL(nd_synchronize);
501
502 static void nd_async_device_register(void *d, async_cookie_t cookie)
503 {
504         struct device *dev = d;
505
506         if (device_add(dev) != 0) {
507                 dev_err(dev, "%s: failed\n", __func__);
508                 put_device(dev);
509         }
510         put_device(dev);
511         if (dev->parent)
512                 put_device(dev->parent);
513 }
514
515 static void nd_async_device_unregister(void *d, async_cookie_t cookie)
516 {
517         struct device *dev = d;
518
519         /* flush bus operations before delete */
520         nvdimm_bus_lock(dev);
521         nvdimm_bus_unlock(dev);
522
523         device_unregister(dev);
524         put_device(dev);
525 }
526
527 void __nd_device_register(struct device *dev)
528 {
529         if (!dev)
530                 return;
531
532         /*
533          * Ensure that region devices always have their NUMA node set as
534          * early as possible. This way we are able to make certain that
535          * any memory associated with the creation and the creation
536          * itself of the region is associated with the correct node.
537          */
538         if (is_nd_region(dev))
539                 set_dev_node(dev, to_nd_region(dev)->numa_node);
540
541         dev->bus = &nvdimm_bus_type;
542         if (dev->parent) {
543                 get_device(dev->parent);
544                 if (dev_to_node(dev) == NUMA_NO_NODE)
545                         set_dev_node(dev, dev_to_node(dev->parent));
546         }
547         get_device(dev);
548
549         async_schedule_dev_domain(nd_async_device_register, dev,
550                                   &nd_async_domain);
551 }
552
553 void nd_device_register(struct device *dev)
554 {
555         device_initialize(dev);
556         __nd_device_register(dev);
557 }
558 EXPORT_SYMBOL(nd_device_register);
559
560 void nd_device_unregister(struct device *dev, enum nd_async_mode mode)
561 {
562         bool killed;
563
564         switch (mode) {
565         case ND_ASYNC:
566                 /*
567                  * In the async case this is being triggered with the
568                  * device lock held and the unregistration work needs to
569                  * be moved out of line iff this is thread has won the
570                  * race to schedule the deletion.
571                  */
572                 if (!kill_device(dev))
573                         return;
574
575                 get_device(dev);
576                 async_schedule_domain(nd_async_device_unregister, dev,
577                                 &nd_async_domain);
578                 break;
579         case ND_SYNC:
580                 /*
581                  * In the sync case the device is being unregistered due
582                  * to a state change of the parent. Claim the kill state
583                  * to synchronize against other unregistration requests,
584                  * or otherwise let the async path handle it if the
585                  * unregistration was already queued.
586                  */
587                 nd_device_lock(dev);
588                 killed = kill_device(dev);
589                 nd_device_unlock(dev);
590
591                 if (!killed)
592                         return;
593
594                 nd_synchronize();
595                 device_unregister(dev);
596                 break;
597         }
598 }
599 EXPORT_SYMBOL(nd_device_unregister);
600
601 /**
602  * __nd_driver_register() - register a region or a namespace driver
603  * @nd_drv: driver to register
604  * @owner: automatically set by nd_driver_register() macro
605  * @mod_name: automatically set by nd_driver_register() macro
606  */
607 int __nd_driver_register(struct nd_device_driver *nd_drv, struct module *owner,
608                 const char *mod_name)
609 {
610         struct device_driver *drv = &nd_drv->drv;
611
612         if (!nd_drv->type) {
613                 pr_debug("driver type bitmask not set (%ps)\n",
614                                 __builtin_return_address(0));
615                 return -EINVAL;
616         }
617
618         if (!nd_drv->probe) {
619                 pr_debug("%s ->probe() must be specified\n", mod_name);
620                 return -EINVAL;
621         }
622
623         drv->bus = &nvdimm_bus_type;
624         drv->owner = owner;
625         drv->mod_name = mod_name;
626
627         return driver_register(drv);
628 }
629 EXPORT_SYMBOL(__nd_driver_register);
630
631 void nvdimm_check_and_set_ro(struct gendisk *disk)
632 {
633         struct device *dev = disk_to_dev(disk)->parent;
634         struct nd_region *nd_region = to_nd_region(dev->parent);
635         int disk_ro = get_disk_ro(disk);
636
637         /*
638          * Upgrade to read-only if the region is read-only preserve as
639          * read-only if the disk is already read-only.
640          */
641         if (disk_ro || nd_region->ro == disk_ro)
642                 return;
643
644         dev_info(dev, "%s read-only, marking %s read-only\n",
645                         dev_name(&nd_region->dev), disk->disk_name);
646         set_disk_ro(disk, 1);
647 }
648 EXPORT_SYMBOL(nvdimm_check_and_set_ro);
649
650 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
651                 char *buf)
652 {
653         return sprintf(buf, ND_DEVICE_MODALIAS_FMT "\n",
654                         to_nd_device_type(dev));
655 }
656 static DEVICE_ATTR_RO(modalias);
657
658 static ssize_t devtype_show(struct device *dev, struct device_attribute *attr,
659                 char *buf)
660 {
661         return sprintf(buf, "%s\n", dev->type->name);
662 }
663 static DEVICE_ATTR_RO(devtype);
664
665 static struct attribute *nd_device_attributes[] = {
666         &dev_attr_modalias.attr,
667         &dev_attr_devtype.attr,
668         NULL,
669 };
670
671 /*
672  * nd_device_attribute_group - generic attributes for all devices on an nd bus
673  */
674 const struct attribute_group nd_device_attribute_group = {
675         .attrs = nd_device_attributes,
676 };
677
678 static ssize_t numa_node_show(struct device *dev,
679                 struct device_attribute *attr, char *buf)
680 {
681         return sprintf(buf, "%d\n", dev_to_node(dev));
682 }
683 static DEVICE_ATTR_RO(numa_node);
684
685 static int nvdimm_dev_to_target_node(struct device *dev)
686 {
687         struct device *parent = dev->parent;
688         struct nd_region *nd_region = NULL;
689
690         if (is_nd_region(dev))
691                 nd_region = to_nd_region(dev);
692         else if (parent && is_nd_region(parent))
693                 nd_region = to_nd_region(parent);
694
695         if (!nd_region)
696                 return NUMA_NO_NODE;
697         return nd_region->target_node;
698 }
699
700 static ssize_t target_node_show(struct device *dev,
701                 struct device_attribute *attr, char *buf)
702 {
703         return sprintf(buf, "%d\n", nvdimm_dev_to_target_node(dev));
704 }
705 static DEVICE_ATTR_RO(target_node);
706
707 static struct attribute *nd_numa_attributes[] = {
708         &dev_attr_numa_node.attr,
709         &dev_attr_target_node.attr,
710         NULL,
711 };
712
713 static umode_t nd_numa_attr_visible(struct kobject *kobj, struct attribute *a,
714                 int n)
715 {
716         struct device *dev = container_of(kobj, typeof(*dev), kobj);
717
718         if (!IS_ENABLED(CONFIG_NUMA))
719                 return 0;
720
721         if (a == &dev_attr_target_node.attr &&
722                         nvdimm_dev_to_target_node(dev) == NUMA_NO_NODE)
723                 return 0;
724
725         return a->mode;
726 }
727
728 /*
729  * nd_numa_attribute_group - NUMA attributes for all devices on an nd bus
730  */
731 const struct attribute_group nd_numa_attribute_group = {
732         .attrs = nd_numa_attributes,
733         .is_visible = nd_numa_attr_visible,
734 };
735
736 int nvdimm_bus_create_ndctl(struct nvdimm_bus *nvdimm_bus)
737 {
738         dev_t devt = MKDEV(nvdimm_bus_major, nvdimm_bus->id);
739         struct device *dev;
740
741         dev = device_create(nd_class, &nvdimm_bus->dev, devt, nvdimm_bus,
742                         "ndctl%d", nvdimm_bus->id);
743
744         if (IS_ERR(dev))
745                 dev_dbg(&nvdimm_bus->dev, "failed to register ndctl%d: %ld\n",
746                                 nvdimm_bus->id, PTR_ERR(dev));
747         return PTR_ERR_OR_ZERO(dev);
748 }
749
750 void nvdimm_bus_destroy_ndctl(struct nvdimm_bus *nvdimm_bus)
751 {
752         device_destroy(nd_class, MKDEV(nvdimm_bus_major, nvdimm_bus->id));
753 }
754
755 static const struct nd_cmd_desc __nd_cmd_dimm_descs[] = {
756         [ND_CMD_IMPLEMENTED] = { },
757         [ND_CMD_SMART] = {
758                 .out_num = 2,
759                 .out_sizes = { 4, 128, },
760         },
761         [ND_CMD_SMART_THRESHOLD] = {
762                 .out_num = 2,
763                 .out_sizes = { 4, 8, },
764         },
765         [ND_CMD_DIMM_FLAGS] = {
766                 .out_num = 2,
767                 .out_sizes = { 4, 4 },
768         },
769         [ND_CMD_GET_CONFIG_SIZE] = {
770                 .out_num = 3,
771                 .out_sizes = { 4, 4, 4, },
772         },
773         [ND_CMD_GET_CONFIG_DATA] = {
774                 .in_num = 2,
775                 .in_sizes = { 4, 4, },
776                 .out_num = 2,
777                 .out_sizes = { 4, UINT_MAX, },
778         },
779         [ND_CMD_SET_CONFIG_DATA] = {
780                 .in_num = 3,
781                 .in_sizes = { 4, 4, UINT_MAX, },
782                 .out_num = 1,
783                 .out_sizes = { 4, },
784         },
785         [ND_CMD_VENDOR] = {
786                 .in_num = 3,
787                 .in_sizes = { 4, 4, UINT_MAX, },
788                 .out_num = 3,
789                 .out_sizes = { 4, 4, UINT_MAX, },
790         },
791         [ND_CMD_CALL] = {
792                 .in_num = 2,
793                 .in_sizes = { sizeof(struct nd_cmd_pkg), UINT_MAX, },
794                 .out_num = 1,
795                 .out_sizes = { UINT_MAX, },
796         },
797 };
798
799 const struct nd_cmd_desc *nd_cmd_dimm_desc(int cmd)
800 {
801         if (cmd < ARRAY_SIZE(__nd_cmd_dimm_descs))
802                 return &__nd_cmd_dimm_descs[cmd];
803         return NULL;
804 }
805 EXPORT_SYMBOL_GPL(nd_cmd_dimm_desc);
806
807 static const struct nd_cmd_desc __nd_cmd_bus_descs[] = {
808         [ND_CMD_IMPLEMENTED] = { },
809         [ND_CMD_ARS_CAP] = {
810                 .in_num = 2,
811                 .in_sizes = { 8, 8, },
812                 .out_num = 4,
813                 .out_sizes = { 4, 4, 4, 4, },
814         },
815         [ND_CMD_ARS_START] = {
816                 .in_num = 5,
817                 .in_sizes = { 8, 8, 2, 1, 5, },
818                 .out_num = 2,
819                 .out_sizes = { 4, 4, },
820         },
821         [ND_CMD_ARS_STATUS] = {
822                 .out_num = 3,
823                 .out_sizes = { 4, 4, UINT_MAX, },
824         },
825         [ND_CMD_CLEAR_ERROR] = {
826                 .in_num = 2,
827                 .in_sizes = { 8, 8, },
828                 .out_num = 3,
829                 .out_sizes = { 4, 4, 8, },
830         },
831         [ND_CMD_CALL] = {
832                 .in_num = 2,
833                 .in_sizes = { sizeof(struct nd_cmd_pkg), UINT_MAX, },
834                 .out_num = 1,
835                 .out_sizes = { UINT_MAX, },
836         },
837 };
838
839 const struct nd_cmd_desc *nd_cmd_bus_desc(int cmd)
840 {
841         if (cmd < ARRAY_SIZE(__nd_cmd_bus_descs))
842                 return &__nd_cmd_bus_descs[cmd];
843         return NULL;
844 }
845 EXPORT_SYMBOL_GPL(nd_cmd_bus_desc);
846
847 u32 nd_cmd_in_size(struct nvdimm *nvdimm, int cmd,
848                 const struct nd_cmd_desc *desc, int idx, void *buf)
849 {
850         if (idx >= desc->in_num)
851                 return UINT_MAX;
852
853         if (desc->in_sizes[idx] < UINT_MAX)
854                 return desc->in_sizes[idx];
855
856         if (nvdimm && cmd == ND_CMD_SET_CONFIG_DATA && idx == 2) {
857                 struct nd_cmd_set_config_hdr *hdr = buf;
858
859                 return hdr->in_length;
860         } else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2) {
861                 struct nd_cmd_vendor_hdr *hdr = buf;
862
863                 return hdr->in_length;
864         } else if (cmd == ND_CMD_CALL) {
865                 struct nd_cmd_pkg *pkg = buf;
866
867                 return pkg->nd_size_in;
868         }
869
870         return UINT_MAX;
871 }
872 EXPORT_SYMBOL_GPL(nd_cmd_in_size);
873
874 u32 nd_cmd_out_size(struct nvdimm *nvdimm, int cmd,
875                 const struct nd_cmd_desc *desc, int idx, const u32 *in_field,
876                 const u32 *out_field, unsigned long remainder)
877 {
878         if (idx >= desc->out_num)
879                 return UINT_MAX;
880
881         if (desc->out_sizes[idx] < UINT_MAX)
882                 return desc->out_sizes[idx];
883
884         if (nvdimm && cmd == ND_CMD_GET_CONFIG_DATA && idx == 1)
885                 return in_field[1];
886         else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2)
887                 return out_field[1];
888         else if (!nvdimm && cmd == ND_CMD_ARS_STATUS && idx == 2) {
889                 /*
890                  * Per table 9-276 ARS Data in ACPI 6.1, out_field[1] is
891                  * "Size of Output Buffer in bytes, including this
892                  * field."
893                  */
894                 if (out_field[1] < 4)
895                         return 0;
896                 /*
897                  * ACPI 6.1 is ambiguous if 'status' is included in the
898                  * output size. If we encounter an output size that
899                  * overshoots the remainder by 4 bytes, assume it was
900                  * including 'status'.
901                  */
902                 if (out_field[1] - 4 == remainder)
903                         return remainder;
904                 return out_field[1] - 8;
905         } else if (cmd == ND_CMD_CALL) {
906                 struct nd_cmd_pkg *pkg = (struct nd_cmd_pkg *) in_field;
907
908                 return pkg->nd_size_out;
909         }
910
911
912         return UINT_MAX;
913 }
914 EXPORT_SYMBOL_GPL(nd_cmd_out_size);
915
916 void wait_nvdimm_bus_probe_idle(struct device *dev)
917 {
918         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
919
920         do {
921                 if (nvdimm_bus->probe_active == 0)
922                         break;
923                 nvdimm_bus_unlock(dev);
924                 nd_device_unlock(dev);
925                 wait_event(nvdimm_bus->wait,
926                                 nvdimm_bus->probe_active == 0);
927                 nd_device_lock(dev);
928                 nvdimm_bus_lock(dev);
929         } while (true);
930 }
931
932 static int nd_pmem_forget_poison_check(struct device *dev, void *data)
933 {
934         struct nd_cmd_clear_error *clear_err =
935                 (struct nd_cmd_clear_error *)data;
936         struct nd_btt *nd_btt = is_nd_btt(dev) ? to_nd_btt(dev) : NULL;
937         struct nd_pfn *nd_pfn = is_nd_pfn(dev) ? to_nd_pfn(dev) : NULL;
938         struct nd_dax *nd_dax = is_nd_dax(dev) ? to_nd_dax(dev) : NULL;
939         struct nd_namespace_common *ndns = NULL;
940         struct nd_namespace_io *nsio;
941         resource_size_t offset = 0, end_trunc = 0, start, end, pstart, pend;
942
943         if (nd_dax || !dev->driver)
944                 return 0;
945
946         start = clear_err->address;
947         end = clear_err->address + clear_err->cleared - 1;
948
949         if (nd_btt || nd_pfn || nd_dax) {
950                 if (nd_btt)
951                         ndns = nd_btt->ndns;
952                 else if (nd_pfn)
953                         ndns = nd_pfn->ndns;
954                 else if (nd_dax)
955                         ndns = nd_dax->nd_pfn.ndns;
956
957                 if (!ndns)
958                         return 0;
959         } else
960                 ndns = to_ndns(dev);
961
962         nsio = to_nd_namespace_io(&ndns->dev);
963         pstart = nsio->res.start + offset;
964         pend = nsio->res.end - end_trunc;
965
966         if ((pstart >= start) && (pend <= end))
967                 return -EBUSY;
968
969         return 0;
970
971 }
972
973 static int nd_ns_forget_poison_check(struct device *dev, void *data)
974 {
975         return device_for_each_child(dev, data, nd_pmem_forget_poison_check);
976 }
977
978 /* set_config requires an idle interleave set */
979 static int nd_cmd_clear_to_send(struct nvdimm_bus *nvdimm_bus,
980                 struct nvdimm *nvdimm, unsigned int cmd, void *data)
981 {
982         struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
983
984         /* ask the bus provider if it would like to block this request */
985         if (nd_desc->clear_to_send) {
986                 int rc = nd_desc->clear_to_send(nd_desc, nvdimm, cmd, data);
987
988                 if (rc)
989                         return rc;
990         }
991
992         /* require clear error to go through the pmem driver */
993         if (!nvdimm && cmd == ND_CMD_CLEAR_ERROR)
994                 return device_for_each_child(&nvdimm_bus->dev, data,
995                                 nd_ns_forget_poison_check);
996
997         if (!nvdimm || cmd != ND_CMD_SET_CONFIG_DATA)
998                 return 0;
999
1000         /* prevent label manipulation while the kernel owns label updates */
1001         wait_nvdimm_bus_probe_idle(&nvdimm_bus->dev);
1002         if (atomic_read(&nvdimm->busy))
1003                 return -EBUSY;
1004         return 0;
1005 }
1006
1007 static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm,
1008                 int read_only, unsigned int ioctl_cmd, unsigned long arg)
1009 {
1010         struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
1011         const struct nd_cmd_desc *desc = NULL;
1012         unsigned int cmd = _IOC_NR(ioctl_cmd);
1013         struct device *dev = &nvdimm_bus->dev;
1014         void __user *p = (void __user *) arg;
1015         char *out_env = NULL, *in_env = NULL;
1016         const char *cmd_name, *dimm_name;
1017         u32 in_len = 0, out_len = 0;
1018         unsigned int func = cmd;
1019         unsigned long cmd_mask;
1020         struct nd_cmd_pkg pkg;
1021         int rc, i, cmd_rc;
1022         void *buf = NULL;
1023         u64 buf_len = 0;
1024
1025         if (nvdimm) {
1026                 desc = nd_cmd_dimm_desc(cmd);
1027                 cmd_name = nvdimm_cmd_name(cmd);
1028                 cmd_mask = nvdimm->cmd_mask;
1029                 dimm_name = dev_name(&nvdimm->dev);
1030         } else {
1031                 desc = nd_cmd_bus_desc(cmd);
1032                 cmd_name = nvdimm_bus_cmd_name(cmd);
1033                 cmd_mask = nd_desc->cmd_mask;
1034                 dimm_name = "bus";
1035         }
1036
1037         /* Validate command family support against bus declared support */
1038         if (cmd == ND_CMD_CALL) {
1039                 unsigned long *mask;
1040
1041                 if (copy_from_user(&pkg, p, sizeof(pkg)))
1042                         return -EFAULT;
1043
1044                 if (nvdimm) {
1045                         if (pkg.nd_family > NVDIMM_FAMILY_MAX)
1046                                 return -EINVAL;
1047                         mask = &nd_desc->dimm_family_mask;
1048                 } else {
1049                         if (pkg.nd_family > NVDIMM_BUS_FAMILY_MAX)
1050                                 return -EINVAL;
1051                         mask = &nd_desc->bus_family_mask;
1052                 }
1053
1054                 if (!test_bit(pkg.nd_family, mask))
1055                         return -EINVAL;
1056         }
1057
1058         if (!desc ||
1059             (desc->out_num + desc->in_num == 0) ||
1060             cmd > ND_CMD_CALL ||
1061             !test_bit(cmd, &cmd_mask))
1062                 return -ENOTTY;
1063
1064         /* fail write commands (when read-only) */
1065         if (read_only)
1066                 switch (cmd) {
1067                 case ND_CMD_VENDOR:
1068                 case ND_CMD_SET_CONFIG_DATA:
1069                 case ND_CMD_ARS_START:
1070                 case ND_CMD_CLEAR_ERROR:
1071                 case ND_CMD_CALL:
1072                         dev_dbg(dev, "'%s' command while read-only.\n",
1073                                         nvdimm ? nvdimm_cmd_name(cmd)
1074                                         : nvdimm_bus_cmd_name(cmd));
1075                         return -EPERM;
1076                 default:
1077                         break;
1078                 }
1079
1080         /* process an input envelope */
1081         in_env = kzalloc(ND_CMD_MAX_ENVELOPE, GFP_KERNEL);
1082         if (!in_env)
1083                 return -ENOMEM;
1084         for (i = 0; i < desc->in_num; i++) {
1085                 u32 in_size, copy;
1086
1087                 in_size = nd_cmd_in_size(nvdimm, cmd, desc, i, in_env);
1088                 if (in_size == UINT_MAX) {
1089                         dev_err(dev, "%s:%s unknown input size cmd: %s field: %d\n",
1090                                         __func__, dimm_name, cmd_name, i);
1091                         rc = -ENXIO;
1092                         goto out;
1093                 }
1094                 if (in_len < ND_CMD_MAX_ENVELOPE)
1095                         copy = min_t(u32, ND_CMD_MAX_ENVELOPE - in_len, in_size);
1096                 else
1097                         copy = 0;
1098                 if (copy && copy_from_user(&in_env[in_len], p + in_len, copy)) {
1099                         rc = -EFAULT;
1100                         goto out;
1101                 }
1102                 in_len += in_size;
1103         }
1104
1105         if (cmd == ND_CMD_CALL) {
1106                 func = pkg.nd_command;
1107                 dev_dbg(dev, "%s, idx: %llu, in: %u, out: %u, len %llu\n",
1108                                 dimm_name, pkg.nd_command,
1109                                 in_len, out_len, buf_len);
1110         }
1111
1112         /* process an output envelope */
1113         out_env = kzalloc(ND_CMD_MAX_ENVELOPE, GFP_KERNEL);
1114         if (!out_env) {
1115                 rc = -ENOMEM;
1116                 goto out;
1117         }
1118
1119         for (i = 0; i < desc->out_num; i++) {
1120                 u32 out_size = nd_cmd_out_size(nvdimm, cmd, desc, i,
1121                                 (u32 *) in_env, (u32 *) out_env, 0);
1122                 u32 copy;
1123
1124                 if (out_size == UINT_MAX) {
1125                         dev_dbg(dev, "%s unknown output size cmd: %s field: %d\n",
1126                                         dimm_name, cmd_name, i);
1127                         rc = -EFAULT;
1128                         goto out;
1129                 }
1130                 if (out_len < ND_CMD_MAX_ENVELOPE)
1131                         copy = min_t(u32, ND_CMD_MAX_ENVELOPE - out_len, out_size);
1132                 else
1133                         copy = 0;
1134                 if (copy && copy_from_user(&out_env[out_len],
1135                                         p + in_len + out_len, copy)) {
1136                         rc = -EFAULT;
1137                         goto out;
1138                 }
1139                 out_len += out_size;
1140         }
1141
1142         buf_len = (u64) out_len + (u64) in_len;
1143         if (buf_len > ND_IOCTL_MAX_BUFLEN) {
1144                 dev_dbg(dev, "%s cmd: %s buf_len: %llu > %d\n", dimm_name,
1145                                 cmd_name, buf_len, ND_IOCTL_MAX_BUFLEN);
1146                 rc = -EINVAL;
1147                 goto out;
1148         }
1149
1150         buf = vmalloc(buf_len);
1151         if (!buf) {
1152                 rc = -ENOMEM;
1153                 goto out;
1154         }
1155
1156         if (copy_from_user(buf, p, buf_len)) {
1157                 rc = -EFAULT;
1158                 goto out;
1159         }
1160
1161         nd_device_lock(dev);
1162         nvdimm_bus_lock(dev);
1163         rc = nd_cmd_clear_to_send(nvdimm_bus, nvdimm, func, buf);
1164         if (rc)
1165                 goto out_unlock;
1166
1167         rc = nd_desc->ndctl(nd_desc, nvdimm, cmd, buf, buf_len, &cmd_rc);
1168         if (rc < 0)
1169                 goto out_unlock;
1170
1171         if (!nvdimm && cmd == ND_CMD_CLEAR_ERROR && cmd_rc >= 0) {
1172                 struct nd_cmd_clear_error *clear_err = buf;
1173
1174                 nvdimm_account_cleared_poison(nvdimm_bus, clear_err->address,
1175                                 clear_err->cleared);
1176         }
1177
1178         if (copy_to_user(p, buf, buf_len))
1179                 rc = -EFAULT;
1180
1181 out_unlock:
1182         nvdimm_bus_unlock(dev);
1183         nd_device_unlock(dev);
1184 out:
1185         kfree(in_env);
1186         kfree(out_env);
1187         vfree(buf);
1188         return rc;
1189 }
1190
1191 enum nd_ioctl_mode {
1192         BUS_IOCTL,
1193         DIMM_IOCTL,
1194 };
1195
1196 static int match_dimm(struct device *dev, void *data)
1197 {
1198         long id = (long) data;
1199
1200         if (is_nvdimm(dev)) {
1201                 struct nvdimm *nvdimm = to_nvdimm(dev);
1202
1203                 return nvdimm->id == id;
1204         }
1205
1206         return 0;
1207 }
1208
1209 static long nd_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
1210                 enum nd_ioctl_mode mode)
1211
1212 {
1213         struct nvdimm_bus *nvdimm_bus, *found = NULL;
1214         long id = (long) file->private_data;
1215         struct nvdimm *nvdimm = NULL;
1216         int rc, ro;
1217
1218         ro = ((file->f_flags & O_ACCMODE) == O_RDONLY);
1219         mutex_lock(&nvdimm_bus_list_mutex);
1220         list_for_each_entry(nvdimm_bus, &nvdimm_bus_list, list) {
1221                 if (mode == DIMM_IOCTL) {
1222                         struct device *dev;
1223
1224                         dev = device_find_child(&nvdimm_bus->dev,
1225                                         file->private_data, match_dimm);
1226                         if (!dev)
1227                                 continue;
1228                         nvdimm = to_nvdimm(dev);
1229                         found = nvdimm_bus;
1230                 } else if (nvdimm_bus->id == id) {
1231                         found = nvdimm_bus;
1232                 }
1233
1234                 if (found) {
1235                         atomic_inc(&nvdimm_bus->ioctl_active);
1236                         break;
1237                 }
1238         }
1239         mutex_unlock(&nvdimm_bus_list_mutex);
1240
1241         if (!found)
1242                 return -ENXIO;
1243
1244         nvdimm_bus = found;
1245         rc = __nd_ioctl(nvdimm_bus, nvdimm, ro, cmd, arg);
1246
1247         if (nvdimm)
1248                 put_device(&nvdimm->dev);
1249         if (atomic_dec_and_test(&nvdimm_bus->ioctl_active))
1250                 wake_up(&nvdimm_bus->wait);
1251
1252         return rc;
1253 }
1254
1255 static long bus_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1256 {
1257         return nd_ioctl(file, cmd, arg, BUS_IOCTL);
1258 }
1259
1260 static long dimm_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1261 {
1262         return nd_ioctl(file, cmd, arg, DIMM_IOCTL);
1263 }
1264
1265 static int nd_open(struct inode *inode, struct file *file)
1266 {
1267         long minor = iminor(inode);
1268
1269         file->private_data = (void *) minor;
1270         return 0;
1271 }
1272
1273 static const struct file_operations nvdimm_bus_fops = {
1274         .owner = THIS_MODULE,
1275         .open = nd_open,
1276         .unlocked_ioctl = bus_ioctl,
1277         .compat_ioctl = compat_ptr_ioctl,
1278         .llseek = noop_llseek,
1279 };
1280
1281 static const struct file_operations nvdimm_fops = {
1282         .owner = THIS_MODULE,
1283         .open = nd_open,
1284         .unlocked_ioctl = dimm_ioctl,
1285         .compat_ioctl = compat_ptr_ioctl,
1286         .llseek = noop_llseek,
1287 };
1288
1289 int __init nvdimm_bus_init(void)
1290 {
1291         int rc;
1292
1293         rc = bus_register(&nvdimm_bus_type);
1294         if (rc)
1295                 return rc;
1296
1297         rc = register_chrdev(0, "ndctl", &nvdimm_bus_fops);
1298         if (rc < 0)
1299                 goto err_bus_chrdev;
1300         nvdimm_bus_major = rc;
1301
1302         rc = register_chrdev(0, "dimmctl", &nvdimm_fops);
1303         if (rc < 0)
1304                 goto err_dimm_chrdev;
1305         nvdimm_major = rc;
1306
1307         nd_class = class_create(THIS_MODULE, "nd");
1308         if (IS_ERR(nd_class)) {
1309                 rc = PTR_ERR(nd_class);
1310                 goto err_class;
1311         }
1312
1313         rc = driver_register(&nd_bus_driver.drv);
1314         if (rc)
1315                 goto err_nd_bus;
1316
1317         return 0;
1318
1319  err_nd_bus:
1320         class_destroy(nd_class);
1321  err_class:
1322         unregister_chrdev(nvdimm_major, "dimmctl");
1323  err_dimm_chrdev:
1324         unregister_chrdev(nvdimm_bus_major, "ndctl");
1325  err_bus_chrdev:
1326         bus_unregister(&nvdimm_bus_type);
1327
1328         return rc;
1329 }
1330
1331 void nvdimm_bus_exit(void)
1332 {
1333         driver_unregister(&nd_bus_driver.drv);
1334         class_destroy(nd_class);
1335         unregister_chrdev(nvdimm_bus_major, "ndctl");
1336         unregister_chrdev(nvdimm_major, "dimmctl");
1337         bus_unregister(&nvdimm_bus_type);
1338         ida_destroy(&nd_ida);
1339 }