Merge miscellaneous libnvdimm updates for 4.21
[sfrench/cifs-2.6.git] / drivers / nvdimm / bus.c
1 /*
2  * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of version 2 of the GNU General Public License as
6  * published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful, but
9  * WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
11  * General Public License for more details.
12  */
13 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14 #include <linux/libnvdimm.h>
15 #include <linux/sched/mm.h>
16 #include <linux/vmalloc.h>
17 #include <linux/uaccess.h>
18 #include <linux/module.h>
19 #include <linux/blkdev.h>
20 #include <linux/fcntl.h>
21 #include <linux/async.h>
22 #include <linux/genhd.h>
23 #include <linux/ndctl.h>
24 #include <linux/sched.h>
25 #include <linux/slab.h>
26 #include <linux/fs.h>
27 #include <linux/io.h>
28 #include <linux/mm.h>
29 #include <linux/nd.h>
30 #include "nd-core.h"
31 #include "nd.h"
32 #include "pfn.h"
33
34 int nvdimm_major;
35 static int nvdimm_bus_major;
36 static struct class *nd_class;
37 static DEFINE_IDA(nd_ida);
38
39 static int to_nd_device_type(struct device *dev)
40 {
41         if (is_nvdimm(dev))
42                 return ND_DEVICE_DIMM;
43         else if (is_memory(dev))
44                 return ND_DEVICE_REGION_PMEM;
45         else if (is_nd_blk(dev))
46                 return ND_DEVICE_REGION_BLK;
47         else if (is_nd_dax(dev))
48                 return ND_DEVICE_DAX_PMEM;
49         else if (is_nd_region(dev->parent))
50                 return nd_region_to_nstype(to_nd_region(dev->parent));
51
52         return 0;
53 }
54
55 static int nvdimm_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
56 {
57         return add_uevent_var(env, "MODALIAS=" ND_DEVICE_MODALIAS_FMT,
58                         to_nd_device_type(dev));
59 }
60
61 static struct module *to_bus_provider(struct device *dev)
62 {
63         /* pin bus providers while regions are enabled */
64         if (is_nd_region(dev)) {
65                 struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
66
67                 return nvdimm_bus->nd_desc->module;
68         }
69         return NULL;
70 }
71
72 static void nvdimm_bus_probe_start(struct nvdimm_bus *nvdimm_bus)
73 {
74         nvdimm_bus_lock(&nvdimm_bus->dev);
75         nvdimm_bus->probe_active++;
76         nvdimm_bus_unlock(&nvdimm_bus->dev);
77 }
78
79 static void nvdimm_bus_probe_end(struct nvdimm_bus *nvdimm_bus)
80 {
81         nvdimm_bus_lock(&nvdimm_bus->dev);
82         if (--nvdimm_bus->probe_active == 0)
83                 wake_up(&nvdimm_bus->probe_wait);
84         nvdimm_bus_unlock(&nvdimm_bus->dev);
85 }
86
87 static int nvdimm_bus_probe(struct device *dev)
88 {
89         struct nd_device_driver *nd_drv = to_nd_device_driver(dev->driver);
90         struct module *provider = to_bus_provider(dev);
91         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
92         int rc;
93
94         if (!try_module_get(provider))
95                 return -ENXIO;
96
97         dev_dbg(&nvdimm_bus->dev, "START: %s.probe(%s)\n",
98                         dev->driver->name, dev_name(dev));
99
100         nvdimm_bus_probe_start(nvdimm_bus);
101         rc = nd_drv->probe(dev);
102         if (rc == 0)
103                 nd_region_probe_success(nvdimm_bus, dev);
104         else
105                 nd_region_disable(nvdimm_bus, dev);
106         nvdimm_bus_probe_end(nvdimm_bus);
107
108         dev_dbg(&nvdimm_bus->dev, "END: %s.probe(%s) = %d\n", dev->driver->name,
109                         dev_name(dev), rc);
110
111         if (rc != 0)
112                 module_put(provider);
113         return rc;
114 }
115
116 static int nvdimm_bus_remove(struct device *dev)
117 {
118         struct nd_device_driver *nd_drv = to_nd_device_driver(dev->driver);
119         struct module *provider = to_bus_provider(dev);
120         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
121         int rc = 0;
122
123         if (nd_drv->remove)
124                 rc = nd_drv->remove(dev);
125         nd_region_disable(nvdimm_bus, dev);
126
127         dev_dbg(&nvdimm_bus->dev, "%s.remove(%s) = %d\n", dev->driver->name,
128                         dev_name(dev), rc);
129         module_put(provider);
130         return rc;
131 }
132
133 static void nvdimm_bus_shutdown(struct device *dev)
134 {
135         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
136         struct nd_device_driver *nd_drv = NULL;
137
138         if (dev->driver)
139                 nd_drv = to_nd_device_driver(dev->driver);
140
141         if (nd_drv && nd_drv->shutdown) {
142                 nd_drv->shutdown(dev);
143                 dev_dbg(&nvdimm_bus->dev, "%s.shutdown(%s)\n",
144                                 dev->driver->name, dev_name(dev));
145         }
146 }
147
148 void nd_device_notify(struct device *dev, enum nvdimm_event event)
149 {
150         device_lock(dev);
151         if (dev->driver) {
152                 struct nd_device_driver *nd_drv;
153
154                 nd_drv = to_nd_device_driver(dev->driver);
155                 if (nd_drv->notify)
156                         nd_drv->notify(dev, event);
157         }
158         device_unlock(dev);
159 }
160 EXPORT_SYMBOL(nd_device_notify);
161
162 void nvdimm_region_notify(struct nd_region *nd_region, enum nvdimm_event event)
163 {
164         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&nd_region->dev);
165
166         if (!nvdimm_bus)
167                 return;
168
169         /* caller is responsible for holding a reference on the device */
170         nd_device_notify(&nd_region->dev, event);
171 }
172 EXPORT_SYMBOL_GPL(nvdimm_region_notify);
173
174 struct clear_badblocks_context {
175         resource_size_t phys, cleared;
176 };
177
178 static int nvdimm_clear_badblocks_region(struct device *dev, void *data)
179 {
180         struct clear_badblocks_context *ctx = data;
181         struct nd_region *nd_region;
182         resource_size_t ndr_end;
183         sector_t sector;
184
185         /* make sure device is a region */
186         if (!is_nd_pmem(dev))
187                 return 0;
188
189         nd_region = to_nd_region(dev);
190         ndr_end = nd_region->ndr_start + nd_region->ndr_size - 1;
191
192         /* make sure we are in the region */
193         if (ctx->phys < nd_region->ndr_start
194                         || (ctx->phys + ctx->cleared) > ndr_end)
195                 return 0;
196
197         sector = (ctx->phys - nd_region->ndr_start) / 512;
198         badblocks_clear(&nd_region->bb, sector, ctx->cleared / 512);
199
200         if (nd_region->bb_state)
201                 sysfs_notify_dirent(nd_region->bb_state);
202
203         return 0;
204 }
205
206 static void nvdimm_clear_badblocks_regions(struct nvdimm_bus *nvdimm_bus,
207                 phys_addr_t phys, u64 cleared)
208 {
209         struct clear_badblocks_context ctx = {
210                 .phys = phys,
211                 .cleared = cleared,
212         };
213
214         device_for_each_child(&nvdimm_bus->dev, &ctx,
215                         nvdimm_clear_badblocks_region);
216 }
217
218 static void nvdimm_account_cleared_poison(struct nvdimm_bus *nvdimm_bus,
219                 phys_addr_t phys, u64 cleared)
220 {
221         if (cleared > 0)
222                 badrange_forget(&nvdimm_bus->badrange, phys, cleared);
223
224         if (cleared > 0 && cleared / 512)
225                 nvdimm_clear_badblocks_regions(nvdimm_bus, phys, cleared);
226 }
227
228 long nvdimm_clear_poison(struct device *dev, phys_addr_t phys,
229                 unsigned int len)
230 {
231         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
232         struct nvdimm_bus_descriptor *nd_desc;
233         struct nd_cmd_clear_error clear_err;
234         struct nd_cmd_ars_cap ars_cap;
235         u32 clear_err_unit, mask;
236         unsigned int noio_flag;
237         int cmd_rc, rc;
238
239         if (!nvdimm_bus)
240                 return -ENXIO;
241
242         nd_desc = nvdimm_bus->nd_desc;
243         /*
244          * if ndctl does not exist, it's PMEM_LEGACY and
245          * we want to just pretend everything is handled.
246          */
247         if (!nd_desc->ndctl)
248                 return len;
249
250         memset(&ars_cap, 0, sizeof(ars_cap));
251         ars_cap.address = phys;
252         ars_cap.length = len;
253         noio_flag = memalloc_noio_save();
254         rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_ARS_CAP, &ars_cap,
255                         sizeof(ars_cap), &cmd_rc);
256         memalloc_noio_restore(noio_flag);
257         if (rc < 0)
258                 return rc;
259         if (cmd_rc < 0)
260                 return cmd_rc;
261         clear_err_unit = ars_cap.clear_err_unit;
262         if (!clear_err_unit || !is_power_of_2(clear_err_unit))
263                 return -ENXIO;
264
265         mask = clear_err_unit - 1;
266         if ((phys | len) & mask)
267                 return -ENXIO;
268         memset(&clear_err, 0, sizeof(clear_err));
269         clear_err.address = phys;
270         clear_err.length = len;
271         noio_flag = memalloc_noio_save();
272         rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_CLEAR_ERROR, &clear_err,
273                         sizeof(clear_err), &cmd_rc);
274         memalloc_noio_restore(noio_flag);
275         if (rc < 0)
276                 return rc;
277         if (cmd_rc < 0)
278                 return cmd_rc;
279
280         nvdimm_account_cleared_poison(nvdimm_bus, phys, clear_err.cleared);
281
282         return clear_err.cleared;
283 }
284 EXPORT_SYMBOL_GPL(nvdimm_clear_poison);
285
286 static int nvdimm_bus_match(struct device *dev, struct device_driver *drv);
287
288 static struct bus_type nvdimm_bus_type = {
289         .name = "nd",
290         .uevent = nvdimm_bus_uevent,
291         .match = nvdimm_bus_match,
292         .probe = nvdimm_bus_probe,
293         .remove = nvdimm_bus_remove,
294         .shutdown = nvdimm_bus_shutdown,
295 };
296
297 static void nvdimm_bus_release(struct device *dev)
298 {
299         struct nvdimm_bus *nvdimm_bus;
300
301         nvdimm_bus = container_of(dev, struct nvdimm_bus, dev);
302         ida_simple_remove(&nd_ida, nvdimm_bus->id);
303         kfree(nvdimm_bus);
304 }
305
306 static bool is_nvdimm_bus(struct device *dev)
307 {
308         return dev->release == nvdimm_bus_release;
309 }
310
311 struct nvdimm_bus *walk_to_nvdimm_bus(struct device *nd_dev)
312 {
313         struct device *dev;
314
315         for (dev = nd_dev; dev; dev = dev->parent)
316                 if (is_nvdimm_bus(dev))
317                         break;
318         dev_WARN_ONCE(nd_dev, !dev, "invalid dev, not on nd bus\n");
319         if (dev)
320                 return to_nvdimm_bus(dev);
321         return NULL;
322 }
323
324 struct nvdimm_bus *to_nvdimm_bus(struct device *dev)
325 {
326         struct nvdimm_bus *nvdimm_bus;
327
328         nvdimm_bus = container_of(dev, struct nvdimm_bus, dev);
329         WARN_ON(!is_nvdimm_bus(dev));
330         return nvdimm_bus;
331 }
332 EXPORT_SYMBOL_GPL(to_nvdimm_bus);
333
334 struct nvdimm_bus *nvdimm_to_bus(struct nvdimm *nvdimm)
335 {
336         return to_nvdimm_bus(nvdimm->dev.parent);
337 }
338 EXPORT_SYMBOL_GPL(nvdimm_to_bus);
339
340 struct nvdimm_bus *nvdimm_bus_register(struct device *parent,
341                 struct nvdimm_bus_descriptor *nd_desc)
342 {
343         struct nvdimm_bus *nvdimm_bus;
344         int rc;
345
346         nvdimm_bus = kzalloc(sizeof(*nvdimm_bus), GFP_KERNEL);
347         if (!nvdimm_bus)
348                 return NULL;
349         INIT_LIST_HEAD(&nvdimm_bus->list);
350         INIT_LIST_HEAD(&nvdimm_bus->mapping_list);
351         init_waitqueue_head(&nvdimm_bus->probe_wait);
352         nvdimm_bus->id = ida_simple_get(&nd_ida, 0, 0, GFP_KERNEL);
353         if (nvdimm_bus->id < 0) {
354                 kfree(nvdimm_bus);
355                 return NULL;
356         }
357         mutex_init(&nvdimm_bus->reconfig_mutex);
358         badrange_init(&nvdimm_bus->badrange);
359         nvdimm_bus->nd_desc = nd_desc;
360         nvdimm_bus->dev.parent = parent;
361         nvdimm_bus->dev.release = nvdimm_bus_release;
362         nvdimm_bus->dev.groups = nd_desc->attr_groups;
363         nvdimm_bus->dev.bus = &nvdimm_bus_type;
364         nvdimm_bus->dev.of_node = nd_desc->of_node;
365         dev_set_name(&nvdimm_bus->dev, "ndbus%d", nvdimm_bus->id);
366         rc = device_register(&nvdimm_bus->dev);
367         if (rc) {
368                 dev_dbg(&nvdimm_bus->dev, "registration failed: %d\n", rc);
369                 goto err;
370         }
371
372         return nvdimm_bus;
373  err:
374         put_device(&nvdimm_bus->dev);
375         return NULL;
376 }
377 EXPORT_SYMBOL_GPL(nvdimm_bus_register);
378
379 void nvdimm_bus_unregister(struct nvdimm_bus *nvdimm_bus)
380 {
381         if (!nvdimm_bus)
382                 return;
383         device_unregister(&nvdimm_bus->dev);
384 }
385 EXPORT_SYMBOL_GPL(nvdimm_bus_unregister);
386
387 static int child_unregister(struct device *dev, void *data)
388 {
389         /*
390          * the singular ndctl class device per bus needs to be
391          * "device_destroy"ed, so skip it here
392          *
393          * i.e. remove classless children
394          */
395         if (dev->class)
396                 return 0;
397
398         if (is_nvdimm(dev)) {
399                 struct nvdimm *nvdimm = to_nvdimm(dev);
400                 bool dev_put = false;
401
402                 /* We are shutting down. Make state frozen artificially. */
403                 nvdimm_bus_lock(dev);
404                 nvdimm->sec.state = NVDIMM_SECURITY_FROZEN;
405                 if (test_and_clear_bit(NDD_WORK_PENDING, &nvdimm->flags))
406                         dev_put = true;
407                 nvdimm_bus_unlock(dev);
408                 cancel_delayed_work_sync(&nvdimm->dwork);
409                 if (dev_put)
410                         put_device(dev);
411         }
412         nd_device_unregister(dev, ND_SYNC);
413
414         return 0;
415 }
416
417 static void free_badrange_list(struct list_head *badrange_list)
418 {
419         struct badrange_entry *bre, *next;
420
421         list_for_each_entry_safe(bre, next, badrange_list, list) {
422                 list_del(&bre->list);
423                 kfree(bre);
424         }
425         list_del_init(badrange_list);
426 }
427
428 static int nd_bus_remove(struct device *dev)
429 {
430         struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
431
432         mutex_lock(&nvdimm_bus_list_mutex);
433         list_del_init(&nvdimm_bus->list);
434         mutex_unlock(&nvdimm_bus_list_mutex);
435
436         nd_synchronize();
437         device_for_each_child(&nvdimm_bus->dev, NULL, child_unregister);
438
439         spin_lock(&nvdimm_bus->badrange.lock);
440         free_badrange_list(&nvdimm_bus->badrange.list);
441         spin_unlock(&nvdimm_bus->badrange.lock);
442
443         nvdimm_bus_destroy_ndctl(nvdimm_bus);
444
445         return 0;
446 }
447
448 static int nd_bus_probe(struct device *dev)
449 {
450         struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
451         int rc;
452
453         rc = nvdimm_bus_create_ndctl(nvdimm_bus);
454         if (rc)
455                 return rc;
456
457         mutex_lock(&nvdimm_bus_list_mutex);
458         list_add_tail(&nvdimm_bus->list, &nvdimm_bus_list);
459         mutex_unlock(&nvdimm_bus_list_mutex);
460
461         /* enable bus provider attributes to look up their local context */
462         dev_set_drvdata(dev, nvdimm_bus->nd_desc);
463
464         return 0;
465 }
466
467 static struct nd_device_driver nd_bus_driver = {
468         .probe = nd_bus_probe,
469         .remove = nd_bus_remove,
470         .drv = {
471                 .name = "nd_bus",
472                 .suppress_bind_attrs = true,
473                 .bus = &nvdimm_bus_type,
474                 .owner = THIS_MODULE,
475                 .mod_name = KBUILD_MODNAME,
476         },
477 };
478
479 static int nvdimm_bus_match(struct device *dev, struct device_driver *drv)
480 {
481         struct nd_device_driver *nd_drv = to_nd_device_driver(drv);
482
483         if (is_nvdimm_bus(dev) && nd_drv == &nd_bus_driver)
484                 return true;
485
486         return !!test_bit(to_nd_device_type(dev), &nd_drv->type);
487 }
488
489 static ASYNC_DOMAIN_EXCLUSIVE(nd_async_domain);
490
491 void nd_synchronize(void)
492 {
493         async_synchronize_full_domain(&nd_async_domain);
494 }
495 EXPORT_SYMBOL_GPL(nd_synchronize);
496
497 static void nd_async_device_register(void *d, async_cookie_t cookie)
498 {
499         struct device *dev = d;
500
501         if (device_add(dev) != 0) {
502                 dev_err(dev, "%s: failed\n", __func__);
503                 put_device(dev);
504         }
505         put_device(dev);
506         if (dev->parent)
507                 put_device(dev->parent);
508 }
509
510 static void nd_async_device_unregister(void *d, async_cookie_t cookie)
511 {
512         struct device *dev = d;
513
514         /* flush bus operations before delete */
515         nvdimm_bus_lock(dev);
516         nvdimm_bus_unlock(dev);
517
518         device_unregister(dev);
519         put_device(dev);
520 }
521
522 void __nd_device_register(struct device *dev)
523 {
524         if (!dev)
525                 return;
526
527         /*
528          * Ensure that region devices always have their NUMA node set as
529          * early as possible. This way we are able to make certain that
530          * any memory associated with the creation and the creation
531          * itself of the region is associated with the correct node.
532          */
533         if (is_nd_region(dev))
534                 set_dev_node(dev, to_nd_region(dev)->numa_node);
535
536         dev->bus = &nvdimm_bus_type;
537         if (dev->parent)
538                 get_device(dev->parent);
539         get_device(dev);
540         async_schedule_domain(nd_async_device_register, dev,
541                         &nd_async_domain);
542 }
543
544 void nd_device_register(struct device *dev)
545 {
546         device_initialize(dev);
547         __nd_device_register(dev);
548 }
549 EXPORT_SYMBOL(nd_device_register);
550
551 void nd_device_unregister(struct device *dev, enum nd_async_mode mode)
552 {
553         switch (mode) {
554         case ND_ASYNC:
555                 get_device(dev);
556                 async_schedule_domain(nd_async_device_unregister, dev,
557                                 &nd_async_domain);
558                 break;
559         case ND_SYNC:
560                 nd_synchronize();
561                 device_unregister(dev);
562                 break;
563         }
564 }
565 EXPORT_SYMBOL(nd_device_unregister);
566
567 /**
568  * __nd_driver_register() - register a region or a namespace driver
569  * @nd_drv: driver to register
570  * @owner: automatically set by nd_driver_register() macro
571  * @mod_name: automatically set by nd_driver_register() macro
572  */
573 int __nd_driver_register(struct nd_device_driver *nd_drv, struct module *owner,
574                 const char *mod_name)
575 {
576         struct device_driver *drv = &nd_drv->drv;
577
578         if (!nd_drv->type) {
579                 pr_debug("driver type bitmask not set (%pf)\n",
580                                 __builtin_return_address(0));
581                 return -EINVAL;
582         }
583
584         if (!nd_drv->probe) {
585                 pr_debug("%s ->probe() must be specified\n", mod_name);
586                 return -EINVAL;
587         }
588
589         drv->bus = &nvdimm_bus_type;
590         drv->owner = owner;
591         drv->mod_name = mod_name;
592
593         return driver_register(drv);
594 }
595 EXPORT_SYMBOL(__nd_driver_register);
596
597 int nvdimm_revalidate_disk(struct gendisk *disk)
598 {
599         struct device *dev = disk_to_dev(disk)->parent;
600         struct nd_region *nd_region = to_nd_region(dev->parent);
601         int disk_ro = get_disk_ro(disk);
602
603         /*
604          * Upgrade to read-only if the region is read-only preserve as
605          * read-only if the disk is already read-only.
606          */
607         if (disk_ro || nd_region->ro == disk_ro)
608                 return 0;
609
610         dev_info(dev, "%s read-only, marking %s read-only\n",
611                         dev_name(&nd_region->dev), disk->disk_name);
612         set_disk_ro(disk, 1);
613
614         return 0;
615
616 }
617 EXPORT_SYMBOL(nvdimm_revalidate_disk);
618
619 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
620                 char *buf)
621 {
622         return sprintf(buf, ND_DEVICE_MODALIAS_FMT "\n",
623                         to_nd_device_type(dev));
624 }
625 static DEVICE_ATTR_RO(modalias);
626
627 static ssize_t devtype_show(struct device *dev, struct device_attribute *attr,
628                 char *buf)
629 {
630         return sprintf(buf, "%s\n", dev->type->name);
631 }
632 static DEVICE_ATTR_RO(devtype);
633
634 static struct attribute *nd_device_attributes[] = {
635         &dev_attr_modalias.attr,
636         &dev_attr_devtype.attr,
637         NULL,
638 };
639
640 /**
641  * nd_device_attribute_group - generic attributes for all devices on an nd bus
642  */
643 struct attribute_group nd_device_attribute_group = {
644         .attrs = nd_device_attributes,
645 };
646 EXPORT_SYMBOL_GPL(nd_device_attribute_group);
647
648 static ssize_t numa_node_show(struct device *dev,
649                 struct device_attribute *attr, char *buf)
650 {
651         return sprintf(buf, "%d\n", dev_to_node(dev));
652 }
653 static DEVICE_ATTR_RO(numa_node);
654
655 static struct attribute *nd_numa_attributes[] = {
656         &dev_attr_numa_node.attr,
657         NULL,
658 };
659
660 static umode_t nd_numa_attr_visible(struct kobject *kobj, struct attribute *a,
661                 int n)
662 {
663         if (!IS_ENABLED(CONFIG_NUMA))
664                 return 0;
665
666         return a->mode;
667 }
668
669 /**
670  * nd_numa_attribute_group - NUMA attributes for all devices on an nd bus
671  */
672 struct attribute_group nd_numa_attribute_group = {
673         .attrs = nd_numa_attributes,
674         .is_visible = nd_numa_attr_visible,
675 };
676 EXPORT_SYMBOL_GPL(nd_numa_attribute_group);
677
678 int nvdimm_bus_create_ndctl(struct nvdimm_bus *nvdimm_bus)
679 {
680         dev_t devt = MKDEV(nvdimm_bus_major, nvdimm_bus->id);
681         struct device *dev;
682
683         dev = device_create(nd_class, &nvdimm_bus->dev, devt, nvdimm_bus,
684                         "ndctl%d", nvdimm_bus->id);
685
686         if (IS_ERR(dev))
687                 dev_dbg(&nvdimm_bus->dev, "failed to register ndctl%d: %ld\n",
688                                 nvdimm_bus->id, PTR_ERR(dev));
689         return PTR_ERR_OR_ZERO(dev);
690 }
691
692 void nvdimm_bus_destroy_ndctl(struct nvdimm_bus *nvdimm_bus)
693 {
694         device_destroy(nd_class, MKDEV(nvdimm_bus_major, nvdimm_bus->id));
695 }
696
697 static const struct nd_cmd_desc __nd_cmd_dimm_descs[] = {
698         [ND_CMD_IMPLEMENTED] = { },
699         [ND_CMD_SMART] = {
700                 .out_num = 2,
701                 .out_sizes = { 4, 128, },
702         },
703         [ND_CMD_SMART_THRESHOLD] = {
704                 .out_num = 2,
705                 .out_sizes = { 4, 8, },
706         },
707         [ND_CMD_DIMM_FLAGS] = {
708                 .out_num = 2,
709                 .out_sizes = { 4, 4 },
710         },
711         [ND_CMD_GET_CONFIG_SIZE] = {
712                 .out_num = 3,
713                 .out_sizes = { 4, 4, 4, },
714         },
715         [ND_CMD_GET_CONFIG_DATA] = {
716                 .in_num = 2,
717                 .in_sizes = { 4, 4, },
718                 .out_num = 2,
719                 .out_sizes = { 4, UINT_MAX, },
720         },
721         [ND_CMD_SET_CONFIG_DATA] = {
722                 .in_num = 3,
723                 .in_sizes = { 4, 4, UINT_MAX, },
724                 .out_num = 1,
725                 .out_sizes = { 4, },
726         },
727         [ND_CMD_VENDOR] = {
728                 .in_num = 3,
729                 .in_sizes = { 4, 4, UINT_MAX, },
730                 .out_num = 3,
731                 .out_sizes = { 4, 4, UINT_MAX, },
732         },
733         [ND_CMD_CALL] = {
734                 .in_num = 2,
735                 .in_sizes = { sizeof(struct nd_cmd_pkg), UINT_MAX, },
736                 .out_num = 1,
737                 .out_sizes = { UINT_MAX, },
738         },
739 };
740
741 const struct nd_cmd_desc *nd_cmd_dimm_desc(int cmd)
742 {
743         if (cmd < ARRAY_SIZE(__nd_cmd_dimm_descs))
744                 return &__nd_cmd_dimm_descs[cmd];
745         return NULL;
746 }
747 EXPORT_SYMBOL_GPL(nd_cmd_dimm_desc);
748
749 static const struct nd_cmd_desc __nd_cmd_bus_descs[] = {
750         [ND_CMD_IMPLEMENTED] = { },
751         [ND_CMD_ARS_CAP] = {
752                 .in_num = 2,
753                 .in_sizes = { 8, 8, },
754                 .out_num = 4,
755                 .out_sizes = { 4, 4, 4, 4, },
756         },
757         [ND_CMD_ARS_START] = {
758                 .in_num = 5,
759                 .in_sizes = { 8, 8, 2, 1, 5, },
760                 .out_num = 2,
761                 .out_sizes = { 4, 4, },
762         },
763         [ND_CMD_ARS_STATUS] = {
764                 .out_num = 3,
765                 .out_sizes = { 4, 4, UINT_MAX, },
766         },
767         [ND_CMD_CLEAR_ERROR] = {
768                 .in_num = 2,
769                 .in_sizes = { 8, 8, },
770                 .out_num = 3,
771                 .out_sizes = { 4, 4, 8, },
772         },
773         [ND_CMD_CALL] = {
774                 .in_num = 2,
775                 .in_sizes = { sizeof(struct nd_cmd_pkg), UINT_MAX, },
776                 .out_num = 1,
777                 .out_sizes = { UINT_MAX, },
778         },
779 };
780
781 const struct nd_cmd_desc *nd_cmd_bus_desc(int cmd)
782 {
783         if (cmd < ARRAY_SIZE(__nd_cmd_bus_descs))
784                 return &__nd_cmd_bus_descs[cmd];
785         return NULL;
786 }
787 EXPORT_SYMBOL_GPL(nd_cmd_bus_desc);
788
789 u32 nd_cmd_in_size(struct nvdimm *nvdimm, int cmd,
790                 const struct nd_cmd_desc *desc, int idx, void *buf)
791 {
792         if (idx >= desc->in_num)
793                 return UINT_MAX;
794
795         if (desc->in_sizes[idx] < UINT_MAX)
796                 return desc->in_sizes[idx];
797
798         if (nvdimm && cmd == ND_CMD_SET_CONFIG_DATA && idx == 2) {
799                 struct nd_cmd_set_config_hdr *hdr = buf;
800
801                 return hdr->in_length;
802         } else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2) {
803                 struct nd_cmd_vendor_hdr *hdr = buf;
804
805                 return hdr->in_length;
806         } else if (cmd == ND_CMD_CALL) {
807                 struct nd_cmd_pkg *pkg = buf;
808
809                 return pkg->nd_size_in;
810         }
811
812         return UINT_MAX;
813 }
814 EXPORT_SYMBOL_GPL(nd_cmd_in_size);
815
816 u32 nd_cmd_out_size(struct nvdimm *nvdimm, int cmd,
817                 const struct nd_cmd_desc *desc, int idx, const u32 *in_field,
818                 const u32 *out_field, unsigned long remainder)
819 {
820         if (idx >= desc->out_num)
821                 return UINT_MAX;
822
823         if (desc->out_sizes[idx] < UINT_MAX)
824                 return desc->out_sizes[idx];
825
826         if (nvdimm && cmd == ND_CMD_GET_CONFIG_DATA && idx == 1)
827                 return in_field[1];
828         else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2)
829                 return out_field[1];
830         else if (!nvdimm && cmd == ND_CMD_ARS_STATUS && idx == 2) {
831                 /*
832                  * Per table 9-276 ARS Data in ACPI 6.1, out_field[1] is
833                  * "Size of Output Buffer in bytes, including this
834                  * field."
835                  */
836                 if (out_field[1] < 4)
837                         return 0;
838                 /*
839                  * ACPI 6.1 is ambiguous if 'status' is included in the
840                  * output size. If we encounter an output size that
841                  * overshoots the remainder by 4 bytes, assume it was
842                  * including 'status'.
843                  */
844                 if (out_field[1] - 4 == remainder)
845                         return remainder;
846                 return out_field[1] - 8;
847         } else if (cmd == ND_CMD_CALL) {
848                 struct nd_cmd_pkg *pkg = (struct nd_cmd_pkg *) in_field;
849
850                 return pkg->nd_size_out;
851         }
852
853
854         return UINT_MAX;
855 }
856 EXPORT_SYMBOL_GPL(nd_cmd_out_size);
857
858 void wait_nvdimm_bus_probe_idle(struct device *dev)
859 {
860         struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
861
862         do {
863                 if (nvdimm_bus->probe_active == 0)
864                         break;
865                 nvdimm_bus_unlock(&nvdimm_bus->dev);
866                 wait_event(nvdimm_bus->probe_wait,
867                                 nvdimm_bus->probe_active == 0);
868                 nvdimm_bus_lock(&nvdimm_bus->dev);
869         } while (true);
870 }
871
872 static int nd_pmem_forget_poison_check(struct device *dev, void *data)
873 {
874         struct nd_cmd_clear_error *clear_err =
875                 (struct nd_cmd_clear_error *)data;
876         struct nd_btt *nd_btt = is_nd_btt(dev) ? to_nd_btt(dev) : NULL;
877         struct nd_pfn *nd_pfn = is_nd_pfn(dev) ? to_nd_pfn(dev) : NULL;
878         struct nd_dax *nd_dax = is_nd_dax(dev) ? to_nd_dax(dev) : NULL;
879         struct nd_namespace_common *ndns = NULL;
880         struct nd_namespace_io *nsio;
881         resource_size_t offset = 0, end_trunc = 0, start, end, pstart, pend;
882
883         if (nd_dax || !dev->driver)
884                 return 0;
885
886         start = clear_err->address;
887         end = clear_err->address + clear_err->cleared - 1;
888
889         if (nd_btt || nd_pfn || nd_dax) {
890                 if (nd_btt)
891                         ndns = nd_btt->ndns;
892                 else if (nd_pfn)
893                         ndns = nd_pfn->ndns;
894                 else if (nd_dax)
895                         ndns = nd_dax->nd_pfn.ndns;
896
897                 if (!ndns)
898                         return 0;
899         } else
900                 ndns = to_ndns(dev);
901
902         nsio = to_nd_namespace_io(&ndns->dev);
903         pstart = nsio->res.start + offset;
904         pend = nsio->res.end - end_trunc;
905
906         if ((pstart >= start) && (pend <= end))
907                 return -EBUSY;
908
909         return 0;
910
911 }
912
913 static int nd_ns_forget_poison_check(struct device *dev, void *data)
914 {
915         return device_for_each_child(dev, data, nd_pmem_forget_poison_check);
916 }
917
918 /* set_config requires an idle interleave set */
919 static int nd_cmd_clear_to_send(struct nvdimm_bus *nvdimm_bus,
920                 struct nvdimm *nvdimm, unsigned int cmd, void *data)
921 {
922         struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
923
924         /* ask the bus provider if it would like to block this request */
925         if (nd_desc->clear_to_send) {
926                 int rc = nd_desc->clear_to_send(nd_desc, nvdimm, cmd, data);
927
928                 if (rc)
929                         return rc;
930         }
931
932         /* require clear error to go through the pmem driver */
933         if (!nvdimm && cmd == ND_CMD_CLEAR_ERROR)
934                 return device_for_each_child(&nvdimm_bus->dev, data,
935                                 nd_ns_forget_poison_check);
936
937         if (!nvdimm || cmd != ND_CMD_SET_CONFIG_DATA)
938                 return 0;
939
940         /* prevent label manipulation while the kernel owns label updates */
941         wait_nvdimm_bus_probe_idle(&nvdimm_bus->dev);
942         if (atomic_read(&nvdimm->busy))
943                 return -EBUSY;
944         return 0;
945 }
946
947 static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm,
948                 int read_only, unsigned int ioctl_cmd, unsigned long arg)
949 {
950         struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
951         static char out_env[ND_CMD_MAX_ENVELOPE];
952         static char in_env[ND_CMD_MAX_ENVELOPE];
953         const struct nd_cmd_desc *desc = NULL;
954         unsigned int cmd = _IOC_NR(ioctl_cmd);
955         struct device *dev = &nvdimm_bus->dev;
956         void __user *p = (void __user *) arg;
957         const char *cmd_name, *dimm_name;
958         u32 in_len = 0, out_len = 0;
959         unsigned int func = cmd;
960         unsigned long cmd_mask;
961         struct nd_cmd_pkg pkg;
962         int rc, i, cmd_rc;
963         u64 buf_len = 0;
964         void *buf;
965
966         if (nvdimm) {
967                 desc = nd_cmd_dimm_desc(cmd);
968                 cmd_name = nvdimm_cmd_name(cmd);
969                 cmd_mask = nvdimm->cmd_mask;
970                 dimm_name = dev_name(&nvdimm->dev);
971         } else {
972                 desc = nd_cmd_bus_desc(cmd);
973                 cmd_name = nvdimm_bus_cmd_name(cmd);
974                 cmd_mask = nd_desc->cmd_mask;
975                 dimm_name = "bus";
976         }
977
978         if (cmd == ND_CMD_CALL) {
979                 if (copy_from_user(&pkg, p, sizeof(pkg)))
980                         return -EFAULT;
981         }
982
983         if (!desc || (desc->out_num + desc->in_num == 0) ||
984                         !test_bit(cmd, &cmd_mask))
985                 return -ENOTTY;
986
987         /* fail write commands (when read-only) */
988         if (read_only)
989                 switch (cmd) {
990                 case ND_CMD_VENDOR:
991                 case ND_CMD_SET_CONFIG_DATA:
992                 case ND_CMD_ARS_START:
993                 case ND_CMD_CLEAR_ERROR:
994                 case ND_CMD_CALL:
995                         dev_dbg(&nvdimm_bus->dev, "'%s' command while read-only.\n",
996                                         nvdimm ? nvdimm_cmd_name(cmd)
997                                         : nvdimm_bus_cmd_name(cmd));
998                         return -EPERM;
999                 default:
1000                         break;
1001                 }
1002
1003         /* process an input envelope */
1004         for (i = 0; i < desc->in_num; i++) {
1005                 u32 in_size, copy;
1006
1007                 in_size = nd_cmd_in_size(nvdimm, cmd, desc, i, in_env);
1008                 if (in_size == UINT_MAX) {
1009                         dev_err(dev, "%s:%s unknown input size cmd: %s field: %d\n",
1010                                         __func__, dimm_name, cmd_name, i);
1011                         return -ENXIO;
1012                 }
1013                 if (in_len < sizeof(in_env))
1014                         copy = min_t(u32, sizeof(in_env) - in_len, in_size);
1015                 else
1016                         copy = 0;
1017                 if (copy && copy_from_user(&in_env[in_len], p + in_len, copy))
1018                         return -EFAULT;
1019                 in_len += in_size;
1020         }
1021
1022         if (cmd == ND_CMD_CALL) {
1023                 func = pkg.nd_command;
1024                 dev_dbg(dev, "%s, idx: %llu, in: %u, out: %u, len %llu\n",
1025                                 dimm_name, pkg.nd_command,
1026                                 in_len, out_len, buf_len);
1027         }
1028
1029         /* process an output envelope */
1030         for (i = 0; i < desc->out_num; i++) {
1031                 u32 out_size = nd_cmd_out_size(nvdimm, cmd, desc, i,
1032                                 (u32 *) in_env, (u32 *) out_env, 0);
1033                 u32 copy;
1034
1035                 if (out_size == UINT_MAX) {
1036                         dev_dbg(dev, "%s unknown output size cmd: %s field: %d\n",
1037                                         dimm_name, cmd_name, i);
1038                         return -EFAULT;
1039                 }
1040                 if (out_len < sizeof(out_env))
1041                         copy = min_t(u32, sizeof(out_env) - out_len, out_size);
1042                 else
1043                         copy = 0;
1044                 if (copy && copy_from_user(&out_env[out_len],
1045                                         p + in_len + out_len, copy))
1046                         return -EFAULT;
1047                 out_len += out_size;
1048         }
1049
1050         buf_len = (u64) out_len + (u64) in_len;
1051         if (buf_len > ND_IOCTL_MAX_BUFLEN) {
1052                 dev_dbg(dev, "%s cmd: %s buf_len: %llu > %d\n", dimm_name,
1053                                 cmd_name, buf_len, ND_IOCTL_MAX_BUFLEN);
1054                 return -EINVAL;
1055         }
1056
1057         buf = vmalloc(buf_len);
1058         if (!buf)
1059                 return -ENOMEM;
1060
1061         if (copy_from_user(buf, p, buf_len)) {
1062                 rc = -EFAULT;
1063                 goto out;
1064         }
1065
1066         nvdimm_bus_lock(&nvdimm_bus->dev);
1067         rc = nd_cmd_clear_to_send(nvdimm_bus, nvdimm, func, buf);
1068         if (rc)
1069                 goto out_unlock;
1070
1071         rc = nd_desc->ndctl(nd_desc, nvdimm, cmd, buf, buf_len, &cmd_rc);
1072         if (rc < 0)
1073                 goto out_unlock;
1074
1075         if (!nvdimm && cmd == ND_CMD_CLEAR_ERROR && cmd_rc >= 0) {
1076                 struct nd_cmd_clear_error *clear_err = buf;
1077
1078                 nvdimm_account_cleared_poison(nvdimm_bus, clear_err->address,
1079                                 clear_err->cleared);
1080         }
1081         nvdimm_bus_unlock(&nvdimm_bus->dev);
1082
1083         if (copy_to_user(p, buf, buf_len))
1084                 rc = -EFAULT;
1085
1086         vfree(buf);
1087         return rc;
1088
1089  out_unlock:
1090         nvdimm_bus_unlock(&nvdimm_bus->dev);
1091  out:
1092         vfree(buf);
1093         return rc;
1094 }
1095
1096 static long nd_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1097 {
1098         long id = (long) file->private_data;
1099         int rc = -ENXIO, ro;
1100         struct nvdimm_bus *nvdimm_bus;
1101
1102         ro = ((file->f_flags & O_ACCMODE) == O_RDONLY);
1103         mutex_lock(&nvdimm_bus_list_mutex);
1104         list_for_each_entry(nvdimm_bus, &nvdimm_bus_list, list) {
1105                 if (nvdimm_bus->id == id) {
1106                         rc = __nd_ioctl(nvdimm_bus, NULL, ro, cmd, arg);
1107                         break;
1108                 }
1109         }
1110         mutex_unlock(&nvdimm_bus_list_mutex);
1111
1112         return rc;
1113 }
1114
1115 static int match_dimm(struct device *dev, void *data)
1116 {
1117         long id = (long) data;
1118
1119         if (is_nvdimm(dev)) {
1120                 struct nvdimm *nvdimm = to_nvdimm(dev);
1121
1122                 return nvdimm->id == id;
1123         }
1124
1125         return 0;
1126 }
1127
1128 static long nvdimm_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1129 {
1130         int rc = -ENXIO, ro;
1131         struct nvdimm_bus *nvdimm_bus;
1132
1133         ro = ((file->f_flags & O_ACCMODE) == O_RDONLY);
1134         mutex_lock(&nvdimm_bus_list_mutex);
1135         list_for_each_entry(nvdimm_bus, &nvdimm_bus_list, list) {
1136                 struct device *dev = device_find_child(&nvdimm_bus->dev,
1137                                 file->private_data, match_dimm);
1138                 struct nvdimm *nvdimm;
1139
1140                 if (!dev)
1141                         continue;
1142
1143                 nvdimm = to_nvdimm(dev);
1144                 rc = __nd_ioctl(nvdimm_bus, nvdimm, ro, cmd, arg);
1145                 put_device(dev);
1146                 break;
1147         }
1148         mutex_unlock(&nvdimm_bus_list_mutex);
1149
1150         return rc;
1151 }
1152
1153 static int nd_open(struct inode *inode, struct file *file)
1154 {
1155         long minor = iminor(inode);
1156
1157         file->private_data = (void *) minor;
1158         return 0;
1159 }
1160
1161 static const struct file_operations nvdimm_bus_fops = {
1162         .owner = THIS_MODULE,
1163         .open = nd_open,
1164         .unlocked_ioctl = nd_ioctl,
1165         .compat_ioctl = nd_ioctl,
1166         .llseek = noop_llseek,
1167 };
1168
1169 static const struct file_operations nvdimm_fops = {
1170         .owner = THIS_MODULE,
1171         .open = nd_open,
1172         .unlocked_ioctl = nvdimm_ioctl,
1173         .compat_ioctl = nvdimm_ioctl,
1174         .llseek = noop_llseek,
1175 };
1176
1177 int __init nvdimm_bus_init(void)
1178 {
1179         int rc;
1180
1181         rc = bus_register(&nvdimm_bus_type);
1182         if (rc)
1183                 return rc;
1184
1185         rc = register_chrdev(0, "ndctl", &nvdimm_bus_fops);
1186         if (rc < 0)
1187                 goto err_bus_chrdev;
1188         nvdimm_bus_major = rc;
1189
1190         rc = register_chrdev(0, "dimmctl", &nvdimm_fops);
1191         if (rc < 0)
1192                 goto err_dimm_chrdev;
1193         nvdimm_major = rc;
1194
1195         nd_class = class_create(THIS_MODULE, "nd");
1196         if (IS_ERR(nd_class)) {
1197                 rc = PTR_ERR(nd_class);
1198                 goto err_class;
1199         }
1200
1201         rc = driver_register(&nd_bus_driver.drv);
1202         if (rc)
1203                 goto err_nd_bus;
1204
1205         return 0;
1206
1207  err_nd_bus:
1208         class_destroy(nd_class);
1209  err_class:
1210         unregister_chrdev(nvdimm_major, "dimmctl");
1211  err_dimm_chrdev:
1212         unregister_chrdev(nvdimm_bus_major, "ndctl");
1213  err_bus_chrdev:
1214         bus_unregister(&nvdimm_bus_type);
1215
1216         return rc;
1217 }
1218
1219 void nvdimm_bus_exit(void)
1220 {
1221         driver_unregister(&nd_bus_driver.drv);
1222         class_destroy(nd_class);
1223         unregister_chrdev(nvdimm_bus_major, "ndctl");
1224         unregister_chrdev(nvdimm_major, "dimmctl");
1225         bus_unregister(&nvdimm_bus_type);
1226         ida_destroy(&nd_ida);
1227 }