xref: /linux/drivers/nvdimm/bus.c (revision b0f84a84fff180718995b1269da2988e5b28be42)
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 static 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->probe_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 	rc = nd_drv->probe(dev);
95 	if (rc == 0)
96 		nd_region_probe_success(nvdimm_bus, dev);
97 	else
98 		nd_region_disable(nvdimm_bus, dev);
99 	nvdimm_bus_probe_end(nvdimm_bus);
100 
101 	dev_dbg(&nvdimm_bus->dev, "END: %s.probe(%s) = %d\n", dev->driver->name,
102 			dev_name(dev), rc);
103 
104 	if (rc != 0)
105 		module_put(provider);
106 	return rc;
107 }
108 
109 static int nvdimm_bus_remove(struct device *dev)
110 {
111 	struct nd_device_driver *nd_drv = to_nd_device_driver(dev->driver);
112 	struct module *provider = to_bus_provider(dev);
113 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
114 	int rc = 0;
115 
116 	if (nd_drv->remove)
117 		rc = nd_drv->remove(dev);
118 	nd_region_disable(nvdimm_bus, dev);
119 
120 	dev_dbg(&nvdimm_bus->dev, "%s.remove(%s) = %d\n", dev->driver->name,
121 			dev_name(dev), rc);
122 	module_put(provider);
123 	return rc;
124 }
125 
126 static void nvdimm_bus_shutdown(struct device *dev)
127 {
128 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
129 	struct nd_device_driver *nd_drv = NULL;
130 
131 	if (dev->driver)
132 		nd_drv = to_nd_device_driver(dev->driver);
133 
134 	if (nd_drv && nd_drv->shutdown) {
135 		nd_drv->shutdown(dev);
136 		dev_dbg(&nvdimm_bus->dev, "%s.shutdown(%s)\n",
137 				dev->driver->name, dev_name(dev));
138 	}
139 }
140 
141 void nd_device_notify(struct device *dev, enum nvdimm_event event)
142 {
143 	device_lock(dev);
144 	if (dev->driver) {
145 		struct nd_device_driver *nd_drv;
146 
147 		nd_drv = to_nd_device_driver(dev->driver);
148 		if (nd_drv->notify)
149 			nd_drv->notify(dev, event);
150 	}
151 	device_unlock(dev);
152 }
153 EXPORT_SYMBOL(nd_device_notify);
154 
155 void nvdimm_region_notify(struct nd_region *nd_region, enum nvdimm_event event)
156 {
157 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&nd_region->dev);
158 
159 	if (!nvdimm_bus)
160 		return;
161 
162 	/* caller is responsible for holding a reference on the device */
163 	nd_device_notify(&nd_region->dev, event);
164 }
165 EXPORT_SYMBOL_GPL(nvdimm_region_notify);
166 
167 struct clear_badblocks_context {
168 	resource_size_t phys, cleared;
169 };
170 
171 static int nvdimm_clear_badblocks_region(struct device *dev, void *data)
172 {
173 	struct clear_badblocks_context *ctx = data;
174 	struct nd_region *nd_region;
175 	resource_size_t ndr_end;
176 	sector_t sector;
177 
178 	/* make sure device is a region */
179 	if (!is_nd_pmem(dev))
180 		return 0;
181 
182 	nd_region = to_nd_region(dev);
183 	ndr_end = nd_region->ndr_start + nd_region->ndr_size - 1;
184 
185 	/* make sure we are in the region */
186 	if (ctx->phys < nd_region->ndr_start
187 			|| (ctx->phys + ctx->cleared) > ndr_end)
188 		return 0;
189 
190 	sector = (ctx->phys - nd_region->ndr_start) / 512;
191 	badblocks_clear(&nd_region->bb, sector, ctx->cleared / 512);
192 
193 	if (nd_region->bb_state)
194 		sysfs_notify_dirent(nd_region->bb_state);
195 
196 	return 0;
197 }
198 
199 static void nvdimm_clear_badblocks_regions(struct nvdimm_bus *nvdimm_bus,
200 		phys_addr_t phys, u64 cleared)
201 {
202 	struct clear_badblocks_context ctx = {
203 		.phys = phys,
204 		.cleared = cleared,
205 	};
206 
207 	device_for_each_child(&nvdimm_bus->dev, &ctx,
208 			nvdimm_clear_badblocks_region);
209 }
210 
211 static void nvdimm_account_cleared_poison(struct nvdimm_bus *nvdimm_bus,
212 		phys_addr_t phys, u64 cleared)
213 {
214 	if (cleared > 0)
215 		badrange_forget(&nvdimm_bus->badrange, phys, cleared);
216 
217 	if (cleared > 0 && cleared / 512)
218 		nvdimm_clear_badblocks_regions(nvdimm_bus, phys, cleared);
219 }
220 
221 long nvdimm_clear_poison(struct device *dev, phys_addr_t phys,
222 		unsigned int len)
223 {
224 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
225 	struct nvdimm_bus_descriptor *nd_desc;
226 	struct nd_cmd_clear_error clear_err;
227 	struct nd_cmd_ars_cap ars_cap;
228 	u32 clear_err_unit, mask;
229 	unsigned int noio_flag;
230 	int cmd_rc, rc;
231 
232 	if (!nvdimm_bus)
233 		return -ENXIO;
234 
235 	nd_desc = nvdimm_bus->nd_desc;
236 	/*
237 	 * if ndctl does not exist, it's PMEM_LEGACY and
238 	 * we want to just pretend everything is handled.
239 	 */
240 	if (!nd_desc->ndctl)
241 		return len;
242 
243 	memset(&ars_cap, 0, sizeof(ars_cap));
244 	ars_cap.address = phys;
245 	ars_cap.length = len;
246 	noio_flag = memalloc_noio_save();
247 	rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_ARS_CAP, &ars_cap,
248 			sizeof(ars_cap), &cmd_rc);
249 	memalloc_noio_restore(noio_flag);
250 	if (rc < 0)
251 		return rc;
252 	if (cmd_rc < 0)
253 		return cmd_rc;
254 	clear_err_unit = ars_cap.clear_err_unit;
255 	if (!clear_err_unit || !is_power_of_2(clear_err_unit))
256 		return -ENXIO;
257 
258 	mask = clear_err_unit - 1;
259 	if ((phys | len) & mask)
260 		return -ENXIO;
261 	memset(&clear_err, 0, sizeof(clear_err));
262 	clear_err.address = phys;
263 	clear_err.length = len;
264 	noio_flag = memalloc_noio_save();
265 	rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_CLEAR_ERROR, &clear_err,
266 			sizeof(clear_err), &cmd_rc);
267 	memalloc_noio_restore(noio_flag);
268 	if (rc < 0)
269 		return rc;
270 	if (cmd_rc < 0)
271 		return cmd_rc;
272 
273 	nvdimm_account_cleared_poison(nvdimm_bus, phys, clear_err.cleared);
274 
275 	return clear_err.cleared;
276 }
277 EXPORT_SYMBOL_GPL(nvdimm_clear_poison);
278 
279 static int nvdimm_bus_match(struct device *dev, struct device_driver *drv);
280 
281 static struct bus_type nvdimm_bus_type = {
282 	.name = "nd",
283 	.uevent = nvdimm_bus_uevent,
284 	.match = nvdimm_bus_match,
285 	.probe = nvdimm_bus_probe,
286 	.remove = nvdimm_bus_remove,
287 	.shutdown = nvdimm_bus_shutdown,
288 };
289 
290 static void nvdimm_bus_release(struct device *dev)
291 {
292 	struct nvdimm_bus *nvdimm_bus;
293 
294 	nvdimm_bus = container_of(dev, struct nvdimm_bus, dev);
295 	ida_simple_remove(&nd_ida, nvdimm_bus->id);
296 	kfree(nvdimm_bus);
297 }
298 
299 static bool is_nvdimm_bus(struct device *dev)
300 {
301 	return dev->release == nvdimm_bus_release;
302 }
303 
304 struct nvdimm_bus *walk_to_nvdimm_bus(struct device *nd_dev)
305 {
306 	struct device *dev;
307 
308 	for (dev = nd_dev; dev; dev = dev->parent)
309 		if (is_nvdimm_bus(dev))
310 			break;
311 	dev_WARN_ONCE(nd_dev, !dev, "invalid dev, not on nd bus\n");
312 	if (dev)
313 		return to_nvdimm_bus(dev);
314 	return NULL;
315 }
316 
317 struct nvdimm_bus *to_nvdimm_bus(struct device *dev)
318 {
319 	struct nvdimm_bus *nvdimm_bus;
320 
321 	nvdimm_bus = container_of(dev, struct nvdimm_bus, dev);
322 	WARN_ON(!is_nvdimm_bus(dev));
323 	return nvdimm_bus;
324 }
325 EXPORT_SYMBOL_GPL(to_nvdimm_bus);
326 
327 struct nvdimm_bus *nvdimm_to_bus(struct nvdimm *nvdimm)
328 {
329 	return to_nvdimm_bus(nvdimm->dev.parent);
330 }
331 EXPORT_SYMBOL_GPL(nvdimm_to_bus);
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->probe_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.release = nvdimm_bus_release;
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 	dev_set_name(&nvdimm_bus->dev, "ndbus%d", nvdimm_bus->id);
359 	rc = device_register(&nvdimm_bus->dev);
360 	if (rc) {
361 		dev_dbg(&nvdimm_bus->dev, "registration failed: %d\n", rc);
362 		goto err;
363 	}
364 
365 	return nvdimm_bus;
366  err:
367 	put_device(&nvdimm_bus->dev);
368 	return NULL;
369 }
370 EXPORT_SYMBOL_GPL(nvdimm_bus_register);
371 
372 void nvdimm_bus_unregister(struct nvdimm_bus *nvdimm_bus)
373 {
374 	if (!nvdimm_bus)
375 		return;
376 	device_unregister(&nvdimm_bus->dev);
377 }
378 EXPORT_SYMBOL_GPL(nvdimm_bus_unregister);
379 
380 static int child_unregister(struct device *dev, void *data)
381 {
382 	/*
383 	 * the singular ndctl class device per bus needs to be
384 	 * "device_destroy"ed, so skip it here
385 	 *
386 	 * i.e. remove classless children
387 	 */
388 	if (dev->class)
389 		return 0;
390 
391 	if (is_nvdimm(dev)) {
392 		struct nvdimm *nvdimm = to_nvdimm(dev);
393 		bool dev_put = false;
394 
395 		/* We are shutting down. Make state frozen artificially. */
396 		nvdimm_bus_lock(dev);
397 		nvdimm->sec.state = NVDIMM_SECURITY_FROZEN;
398 		if (test_and_clear_bit(NDD_WORK_PENDING, &nvdimm->flags))
399 			dev_put = true;
400 		nvdimm_bus_unlock(dev);
401 		cancel_delayed_work_sync(&nvdimm->dwork);
402 		if (dev_put)
403 			put_device(dev);
404 	}
405 	nd_device_unregister(dev, ND_SYNC);
406 
407 	return 0;
408 }
409 
410 static void free_badrange_list(struct list_head *badrange_list)
411 {
412 	struct badrange_entry *bre, *next;
413 
414 	list_for_each_entry_safe(bre, next, badrange_list, list) {
415 		list_del(&bre->list);
416 		kfree(bre);
417 	}
418 	list_del_init(badrange_list);
419 }
420 
421 static int nd_bus_remove(struct device *dev)
422 {
423 	struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
424 
425 	mutex_lock(&nvdimm_bus_list_mutex);
426 	list_del_init(&nvdimm_bus->list);
427 	mutex_unlock(&nvdimm_bus_list_mutex);
428 
429 	nd_synchronize();
430 	device_for_each_child(&nvdimm_bus->dev, NULL, child_unregister);
431 
432 	spin_lock(&nvdimm_bus->badrange.lock);
433 	free_badrange_list(&nvdimm_bus->badrange.list);
434 	spin_unlock(&nvdimm_bus->badrange.lock);
435 
436 	nvdimm_bus_destroy_ndctl(nvdimm_bus);
437 
438 	return 0;
439 }
440 
441 static int nd_bus_probe(struct device *dev)
442 {
443 	struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
444 	int rc;
445 
446 	rc = nvdimm_bus_create_ndctl(nvdimm_bus);
447 	if (rc)
448 		return rc;
449 
450 	mutex_lock(&nvdimm_bus_list_mutex);
451 	list_add_tail(&nvdimm_bus->list, &nvdimm_bus_list);
452 	mutex_unlock(&nvdimm_bus_list_mutex);
453 
454 	/* enable bus provider attributes to look up their local context */
455 	dev_set_drvdata(dev, nvdimm_bus->nd_desc);
456 
457 	return 0;
458 }
459 
460 static struct nd_device_driver nd_bus_driver = {
461 	.probe = nd_bus_probe,
462 	.remove = nd_bus_remove,
463 	.drv = {
464 		.name = "nd_bus",
465 		.suppress_bind_attrs = true,
466 		.bus = &nvdimm_bus_type,
467 		.owner = THIS_MODULE,
468 		.mod_name = KBUILD_MODNAME,
469 	},
470 };
471 
472 static int nvdimm_bus_match(struct device *dev, struct device_driver *drv)
473 {
474 	struct nd_device_driver *nd_drv = to_nd_device_driver(drv);
475 
476 	if (is_nvdimm_bus(dev) && nd_drv == &nd_bus_driver)
477 		return true;
478 
479 	return !!test_bit(to_nd_device_type(dev), &nd_drv->type);
480 }
481 
482 static ASYNC_DOMAIN_EXCLUSIVE(nd_async_domain);
483 
484 void nd_synchronize(void)
485 {
486 	async_synchronize_full_domain(&nd_async_domain);
487 }
488 EXPORT_SYMBOL_GPL(nd_synchronize);
489 
490 static void nd_async_device_register(void *d, async_cookie_t cookie)
491 {
492 	struct device *dev = d;
493 
494 	if (device_add(dev) != 0) {
495 		dev_err(dev, "%s: failed\n", __func__);
496 		put_device(dev);
497 	}
498 	put_device(dev);
499 	if (dev->parent)
500 		put_device(dev->parent);
501 }
502 
503 static void nd_async_device_unregister(void *d, async_cookie_t cookie)
504 {
505 	struct device *dev = d;
506 
507 	/* flush bus operations before delete */
508 	nvdimm_bus_lock(dev);
509 	nvdimm_bus_unlock(dev);
510 
511 	device_unregister(dev);
512 	put_device(dev);
513 }
514 
515 void __nd_device_register(struct device *dev)
516 {
517 	if (!dev)
518 		return;
519 
520 	/*
521 	 * Ensure that region devices always have their NUMA node set as
522 	 * early as possible. This way we are able to make certain that
523 	 * any memory associated with the creation and the creation
524 	 * itself of the region is associated with the correct node.
525 	 */
526 	if (is_nd_region(dev))
527 		set_dev_node(dev, to_nd_region(dev)->numa_node);
528 
529 	dev->bus = &nvdimm_bus_type;
530 	if (dev->parent) {
531 		get_device(dev->parent);
532 		if (dev_to_node(dev) == NUMA_NO_NODE)
533 			set_dev_node(dev, dev_to_node(dev->parent));
534 	}
535 	get_device(dev);
536 
537 	async_schedule_dev_domain(nd_async_device_register, dev,
538 				  &nd_async_domain);
539 }
540 
541 void nd_device_register(struct device *dev)
542 {
543 	device_initialize(dev);
544 	__nd_device_register(dev);
545 }
546 EXPORT_SYMBOL(nd_device_register);
547 
548 void nd_device_unregister(struct device *dev, enum nd_async_mode mode)
549 {
550 	switch (mode) {
551 	case ND_ASYNC:
552 		get_device(dev);
553 		async_schedule_domain(nd_async_device_unregister, dev,
554 				&nd_async_domain);
555 		break;
556 	case ND_SYNC:
557 		nd_synchronize();
558 		device_unregister(dev);
559 		break;
560 	}
561 }
562 EXPORT_SYMBOL(nd_device_unregister);
563 
564 /**
565  * __nd_driver_register() - register a region or a namespace driver
566  * @nd_drv: driver to register
567  * @owner: automatically set by nd_driver_register() macro
568  * @mod_name: automatically set by nd_driver_register() macro
569  */
570 int __nd_driver_register(struct nd_device_driver *nd_drv, struct module *owner,
571 		const char *mod_name)
572 {
573 	struct device_driver *drv = &nd_drv->drv;
574 
575 	if (!nd_drv->type) {
576 		pr_debug("driver type bitmask not set (%ps)\n",
577 				__builtin_return_address(0));
578 		return -EINVAL;
579 	}
580 
581 	if (!nd_drv->probe) {
582 		pr_debug("%s ->probe() must be specified\n", mod_name);
583 		return -EINVAL;
584 	}
585 
586 	drv->bus = &nvdimm_bus_type;
587 	drv->owner = owner;
588 	drv->mod_name = mod_name;
589 
590 	return driver_register(drv);
591 }
592 EXPORT_SYMBOL(__nd_driver_register);
593 
594 int nvdimm_revalidate_disk(struct gendisk *disk)
595 {
596 	struct device *dev = disk_to_dev(disk)->parent;
597 	struct nd_region *nd_region = to_nd_region(dev->parent);
598 	int disk_ro = get_disk_ro(disk);
599 
600 	/*
601 	 * Upgrade to read-only if the region is read-only preserve as
602 	 * read-only if the disk is already read-only.
603 	 */
604 	if (disk_ro || nd_region->ro == disk_ro)
605 		return 0;
606 
607 	dev_info(dev, "%s read-only, marking %s read-only\n",
608 			dev_name(&nd_region->dev), disk->disk_name);
609 	set_disk_ro(disk, 1);
610 
611 	return 0;
612 
613 }
614 EXPORT_SYMBOL(nvdimm_revalidate_disk);
615 
616 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
617 		char *buf)
618 {
619 	return sprintf(buf, ND_DEVICE_MODALIAS_FMT "\n",
620 			to_nd_device_type(dev));
621 }
622 static DEVICE_ATTR_RO(modalias);
623 
624 static ssize_t devtype_show(struct device *dev, struct device_attribute *attr,
625 		char *buf)
626 {
627 	return sprintf(buf, "%s\n", dev->type->name);
628 }
629 static DEVICE_ATTR_RO(devtype);
630 
631 static struct attribute *nd_device_attributes[] = {
632 	&dev_attr_modalias.attr,
633 	&dev_attr_devtype.attr,
634 	NULL,
635 };
636 
637 /*
638  * nd_device_attribute_group - generic attributes for all devices on an nd bus
639  */
640 struct attribute_group nd_device_attribute_group = {
641 	.attrs = nd_device_attributes,
642 };
643 EXPORT_SYMBOL_GPL(nd_device_attribute_group);
644 
645 static ssize_t numa_node_show(struct device *dev,
646 		struct device_attribute *attr, char *buf)
647 {
648 	return sprintf(buf, "%d\n", dev_to_node(dev));
649 }
650 static DEVICE_ATTR_RO(numa_node);
651 
652 static struct attribute *nd_numa_attributes[] = {
653 	&dev_attr_numa_node.attr,
654 	NULL,
655 };
656 
657 static umode_t nd_numa_attr_visible(struct kobject *kobj, struct attribute *a,
658 		int n)
659 {
660 	if (!IS_ENABLED(CONFIG_NUMA))
661 		return 0;
662 
663 	return a->mode;
664 }
665 
666 /*
667  * nd_numa_attribute_group - NUMA attributes for all devices on an nd bus
668  */
669 struct attribute_group nd_numa_attribute_group = {
670 	.attrs = nd_numa_attributes,
671 	.is_visible = nd_numa_attr_visible,
672 };
673 EXPORT_SYMBOL_GPL(nd_numa_attribute_group);
674 
675 int nvdimm_bus_create_ndctl(struct nvdimm_bus *nvdimm_bus)
676 {
677 	dev_t devt = MKDEV(nvdimm_bus_major, nvdimm_bus->id);
678 	struct device *dev;
679 
680 	dev = device_create(nd_class, &nvdimm_bus->dev, devt, nvdimm_bus,
681 			"ndctl%d", nvdimm_bus->id);
682 
683 	if (IS_ERR(dev))
684 		dev_dbg(&nvdimm_bus->dev, "failed to register ndctl%d: %ld\n",
685 				nvdimm_bus->id, PTR_ERR(dev));
686 	return PTR_ERR_OR_ZERO(dev);
687 }
688 
689 void nvdimm_bus_destroy_ndctl(struct nvdimm_bus *nvdimm_bus)
690 {
691 	device_destroy(nd_class, MKDEV(nvdimm_bus_major, nvdimm_bus->id));
692 }
693 
694 static const struct nd_cmd_desc __nd_cmd_dimm_descs[] = {
695 	[ND_CMD_IMPLEMENTED] = { },
696 	[ND_CMD_SMART] = {
697 		.out_num = 2,
698 		.out_sizes = { 4, 128, },
699 	},
700 	[ND_CMD_SMART_THRESHOLD] = {
701 		.out_num = 2,
702 		.out_sizes = { 4, 8, },
703 	},
704 	[ND_CMD_DIMM_FLAGS] = {
705 		.out_num = 2,
706 		.out_sizes = { 4, 4 },
707 	},
708 	[ND_CMD_GET_CONFIG_SIZE] = {
709 		.out_num = 3,
710 		.out_sizes = { 4, 4, 4, },
711 	},
712 	[ND_CMD_GET_CONFIG_DATA] = {
713 		.in_num = 2,
714 		.in_sizes = { 4, 4, },
715 		.out_num = 2,
716 		.out_sizes = { 4, UINT_MAX, },
717 	},
718 	[ND_CMD_SET_CONFIG_DATA] = {
719 		.in_num = 3,
720 		.in_sizes = { 4, 4, UINT_MAX, },
721 		.out_num = 1,
722 		.out_sizes = { 4, },
723 	},
724 	[ND_CMD_VENDOR] = {
725 		.in_num = 3,
726 		.in_sizes = { 4, 4, UINT_MAX, },
727 		.out_num = 3,
728 		.out_sizes = { 4, 4, UINT_MAX, },
729 	},
730 	[ND_CMD_CALL] = {
731 		.in_num = 2,
732 		.in_sizes = { sizeof(struct nd_cmd_pkg), UINT_MAX, },
733 		.out_num = 1,
734 		.out_sizes = { UINT_MAX, },
735 	},
736 };
737 
738 const struct nd_cmd_desc *nd_cmd_dimm_desc(int cmd)
739 {
740 	if (cmd < ARRAY_SIZE(__nd_cmd_dimm_descs))
741 		return &__nd_cmd_dimm_descs[cmd];
742 	return NULL;
743 }
744 EXPORT_SYMBOL_GPL(nd_cmd_dimm_desc);
745 
746 static const struct nd_cmd_desc __nd_cmd_bus_descs[] = {
747 	[ND_CMD_IMPLEMENTED] = { },
748 	[ND_CMD_ARS_CAP] = {
749 		.in_num = 2,
750 		.in_sizes = { 8, 8, },
751 		.out_num = 4,
752 		.out_sizes = { 4, 4, 4, 4, },
753 	},
754 	[ND_CMD_ARS_START] = {
755 		.in_num = 5,
756 		.in_sizes = { 8, 8, 2, 1, 5, },
757 		.out_num = 2,
758 		.out_sizes = { 4, 4, },
759 	},
760 	[ND_CMD_ARS_STATUS] = {
761 		.out_num = 3,
762 		.out_sizes = { 4, 4, UINT_MAX, },
763 	},
764 	[ND_CMD_CLEAR_ERROR] = {
765 		.in_num = 2,
766 		.in_sizes = { 8, 8, },
767 		.out_num = 3,
768 		.out_sizes = { 4, 4, 8, },
769 	},
770 	[ND_CMD_CALL] = {
771 		.in_num = 2,
772 		.in_sizes = { sizeof(struct nd_cmd_pkg), UINT_MAX, },
773 		.out_num = 1,
774 		.out_sizes = { UINT_MAX, },
775 	},
776 };
777 
778 const struct nd_cmd_desc *nd_cmd_bus_desc(int cmd)
779 {
780 	if (cmd < ARRAY_SIZE(__nd_cmd_bus_descs))
781 		return &__nd_cmd_bus_descs[cmd];
782 	return NULL;
783 }
784 EXPORT_SYMBOL_GPL(nd_cmd_bus_desc);
785 
786 u32 nd_cmd_in_size(struct nvdimm *nvdimm, int cmd,
787 		const struct nd_cmd_desc *desc, int idx, void *buf)
788 {
789 	if (idx >= desc->in_num)
790 		return UINT_MAX;
791 
792 	if (desc->in_sizes[idx] < UINT_MAX)
793 		return desc->in_sizes[idx];
794 
795 	if (nvdimm && cmd == ND_CMD_SET_CONFIG_DATA && idx == 2) {
796 		struct nd_cmd_set_config_hdr *hdr = buf;
797 
798 		return hdr->in_length;
799 	} else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2) {
800 		struct nd_cmd_vendor_hdr *hdr = buf;
801 
802 		return hdr->in_length;
803 	} else if (cmd == ND_CMD_CALL) {
804 		struct nd_cmd_pkg *pkg = buf;
805 
806 		return pkg->nd_size_in;
807 	}
808 
809 	return UINT_MAX;
810 }
811 EXPORT_SYMBOL_GPL(nd_cmd_in_size);
812 
813 u32 nd_cmd_out_size(struct nvdimm *nvdimm, int cmd,
814 		const struct nd_cmd_desc *desc, int idx, const u32 *in_field,
815 		const u32 *out_field, unsigned long remainder)
816 {
817 	if (idx >= desc->out_num)
818 		return UINT_MAX;
819 
820 	if (desc->out_sizes[idx] < UINT_MAX)
821 		return desc->out_sizes[idx];
822 
823 	if (nvdimm && cmd == ND_CMD_GET_CONFIG_DATA && idx == 1)
824 		return in_field[1];
825 	else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2)
826 		return out_field[1];
827 	else if (!nvdimm && cmd == ND_CMD_ARS_STATUS && idx == 2) {
828 		/*
829 		 * Per table 9-276 ARS Data in ACPI 6.1, out_field[1] is
830 		 * "Size of Output Buffer in bytes, including this
831 		 * field."
832 		 */
833 		if (out_field[1] < 4)
834 			return 0;
835 		/*
836 		 * ACPI 6.1 is ambiguous if 'status' is included in the
837 		 * output size. If we encounter an output size that
838 		 * overshoots the remainder by 4 bytes, assume it was
839 		 * including 'status'.
840 		 */
841 		if (out_field[1] - 4 == remainder)
842 			return remainder;
843 		return out_field[1] - 8;
844 	} else if (cmd == ND_CMD_CALL) {
845 		struct nd_cmd_pkg *pkg = (struct nd_cmd_pkg *) in_field;
846 
847 		return pkg->nd_size_out;
848 	}
849 
850 
851 	return UINT_MAX;
852 }
853 EXPORT_SYMBOL_GPL(nd_cmd_out_size);
854 
855 void wait_nvdimm_bus_probe_idle(struct device *dev)
856 {
857 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
858 
859 	do {
860 		if (nvdimm_bus->probe_active == 0)
861 			break;
862 		nvdimm_bus_unlock(&nvdimm_bus->dev);
863 		wait_event(nvdimm_bus->probe_wait,
864 				nvdimm_bus->probe_active == 0);
865 		nvdimm_bus_lock(&nvdimm_bus->dev);
866 	} while (true);
867 }
868 
869 static int nd_pmem_forget_poison_check(struct device *dev, void *data)
870 {
871 	struct nd_cmd_clear_error *clear_err =
872 		(struct nd_cmd_clear_error *)data;
873 	struct nd_btt *nd_btt = is_nd_btt(dev) ? to_nd_btt(dev) : NULL;
874 	struct nd_pfn *nd_pfn = is_nd_pfn(dev) ? to_nd_pfn(dev) : NULL;
875 	struct nd_dax *nd_dax = is_nd_dax(dev) ? to_nd_dax(dev) : NULL;
876 	struct nd_namespace_common *ndns = NULL;
877 	struct nd_namespace_io *nsio;
878 	resource_size_t offset = 0, end_trunc = 0, start, end, pstart, pend;
879 
880 	if (nd_dax || !dev->driver)
881 		return 0;
882 
883 	start = clear_err->address;
884 	end = clear_err->address + clear_err->cleared - 1;
885 
886 	if (nd_btt || nd_pfn || nd_dax) {
887 		if (nd_btt)
888 			ndns = nd_btt->ndns;
889 		else if (nd_pfn)
890 			ndns = nd_pfn->ndns;
891 		else if (nd_dax)
892 			ndns = nd_dax->nd_pfn.ndns;
893 
894 		if (!ndns)
895 			return 0;
896 	} else
897 		ndns = to_ndns(dev);
898 
899 	nsio = to_nd_namespace_io(&ndns->dev);
900 	pstart = nsio->res.start + offset;
901 	pend = nsio->res.end - end_trunc;
902 
903 	if ((pstart >= start) && (pend <= end))
904 		return -EBUSY;
905 
906 	return 0;
907 
908 }
909 
910 static int nd_ns_forget_poison_check(struct device *dev, void *data)
911 {
912 	return device_for_each_child(dev, data, nd_pmem_forget_poison_check);
913 }
914 
915 /* set_config requires an idle interleave set */
916 static int nd_cmd_clear_to_send(struct nvdimm_bus *nvdimm_bus,
917 		struct nvdimm *nvdimm, unsigned int cmd, void *data)
918 {
919 	struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
920 
921 	/* ask the bus provider if it would like to block this request */
922 	if (nd_desc->clear_to_send) {
923 		int rc = nd_desc->clear_to_send(nd_desc, nvdimm, cmd, data);
924 
925 		if (rc)
926 			return rc;
927 	}
928 
929 	/* require clear error to go through the pmem driver */
930 	if (!nvdimm && cmd == ND_CMD_CLEAR_ERROR)
931 		return device_for_each_child(&nvdimm_bus->dev, data,
932 				nd_ns_forget_poison_check);
933 
934 	if (!nvdimm || cmd != ND_CMD_SET_CONFIG_DATA)
935 		return 0;
936 
937 	/* prevent label manipulation while the kernel owns label updates */
938 	wait_nvdimm_bus_probe_idle(&nvdimm_bus->dev);
939 	if (atomic_read(&nvdimm->busy))
940 		return -EBUSY;
941 	return 0;
942 }
943 
944 static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm,
945 		int read_only, unsigned int ioctl_cmd, unsigned long arg)
946 {
947 	struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
948 	static char out_env[ND_CMD_MAX_ENVELOPE];
949 	static char in_env[ND_CMD_MAX_ENVELOPE];
950 	const struct nd_cmd_desc *desc = NULL;
951 	unsigned int cmd = _IOC_NR(ioctl_cmd);
952 	struct device *dev = &nvdimm_bus->dev;
953 	void __user *p = (void __user *) arg;
954 	const char *cmd_name, *dimm_name;
955 	u32 in_len = 0, out_len = 0;
956 	unsigned int func = cmd;
957 	unsigned long cmd_mask;
958 	struct nd_cmd_pkg pkg;
959 	int rc, i, cmd_rc;
960 	u64 buf_len = 0;
961 	void *buf;
962 
963 	if (nvdimm) {
964 		desc = nd_cmd_dimm_desc(cmd);
965 		cmd_name = nvdimm_cmd_name(cmd);
966 		cmd_mask = nvdimm->cmd_mask;
967 		dimm_name = dev_name(&nvdimm->dev);
968 	} else {
969 		desc = nd_cmd_bus_desc(cmd);
970 		cmd_name = nvdimm_bus_cmd_name(cmd);
971 		cmd_mask = nd_desc->cmd_mask;
972 		dimm_name = "bus";
973 	}
974 
975 	if (cmd == ND_CMD_CALL) {
976 		if (copy_from_user(&pkg, p, sizeof(pkg)))
977 			return -EFAULT;
978 	}
979 
980 	if (!desc || (desc->out_num + desc->in_num == 0) ||
981 			!test_bit(cmd, &cmd_mask))
982 		return -ENOTTY;
983 
984 	/* fail write commands (when read-only) */
985 	if (read_only)
986 		switch (cmd) {
987 		case ND_CMD_VENDOR:
988 		case ND_CMD_SET_CONFIG_DATA:
989 		case ND_CMD_ARS_START:
990 		case ND_CMD_CLEAR_ERROR:
991 		case ND_CMD_CALL:
992 			dev_dbg(&nvdimm_bus->dev, "'%s' command while read-only.\n",
993 					nvdimm ? nvdimm_cmd_name(cmd)
994 					: nvdimm_bus_cmd_name(cmd));
995 			return -EPERM;
996 		default:
997 			break;
998 		}
999 
1000 	/* process an input envelope */
1001 	for (i = 0; i < desc->in_num; i++) {
1002 		u32 in_size, copy;
1003 
1004 		in_size = nd_cmd_in_size(nvdimm, cmd, desc, i, in_env);
1005 		if (in_size == UINT_MAX) {
1006 			dev_err(dev, "%s:%s unknown input size cmd: %s field: %d\n",
1007 					__func__, dimm_name, cmd_name, i);
1008 			return -ENXIO;
1009 		}
1010 		if (in_len < sizeof(in_env))
1011 			copy = min_t(u32, sizeof(in_env) - in_len, in_size);
1012 		else
1013 			copy = 0;
1014 		if (copy && copy_from_user(&in_env[in_len], p + in_len, copy))
1015 			return -EFAULT;
1016 		in_len += in_size;
1017 	}
1018 
1019 	if (cmd == ND_CMD_CALL) {
1020 		func = pkg.nd_command;
1021 		dev_dbg(dev, "%s, idx: %llu, in: %u, out: %u, len %llu\n",
1022 				dimm_name, pkg.nd_command,
1023 				in_len, out_len, buf_len);
1024 	}
1025 
1026 	/* process an output envelope */
1027 	for (i = 0; i < desc->out_num; i++) {
1028 		u32 out_size = nd_cmd_out_size(nvdimm, cmd, desc, i,
1029 				(u32 *) in_env, (u32 *) out_env, 0);
1030 		u32 copy;
1031 
1032 		if (out_size == UINT_MAX) {
1033 			dev_dbg(dev, "%s unknown output size cmd: %s field: %d\n",
1034 					dimm_name, cmd_name, i);
1035 			return -EFAULT;
1036 		}
1037 		if (out_len < sizeof(out_env))
1038 			copy = min_t(u32, sizeof(out_env) - out_len, out_size);
1039 		else
1040 			copy = 0;
1041 		if (copy && copy_from_user(&out_env[out_len],
1042 					p + in_len + out_len, copy))
1043 			return -EFAULT;
1044 		out_len += out_size;
1045 	}
1046 
1047 	buf_len = (u64) out_len + (u64) in_len;
1048 	if (buf_len > ND_IOCTL_MAX_BUFLEN) {
1049 		dev_dbg(dev, "%s cmd: %s buf_len: %llu > %d\n", dimm_name,
1050 				cmd_name, buf_len, ND_IOCTL_MAX_BUFLEN);
1051 		return -EINVAL;
1052 	}
1053 
1054 	buf = vmalloc(buf_len);
1055 	if (!buf)
1056 		return -ENOMEM;
1057 
1058 	if (copy_from_user(buf, p, buf_len)) {
1059 		rc = -EFAULT;
1060 		goto out;
1061 	}
1062 
1063 	nvdimm_bus_lock(&nvdimm_bus->dev);
1064 	rc = nd_cmd_clear_to_send(nvdimm_bus, nvdimm, func, buf);
1065 	if (rc)
1066 		goto out_unlock;
1067 
1068 	rc = nd_desc->ndctl(nd_desc, nvdimm, cmd, buf, buf_len, &cmd_rc);
1069 	if (rc < 0)
1070 		goto out_unlock;
1071 
1072 	if (!nvdimm && cmd == ND_CMD_CLEAR_ERROR && cmd_rc >= 0) {
1073 		struct nd_cmd_clear_error *clear_err = buf;
1074 
1075 		nvdimm_account_cleared_poison(nvdimm_bus, clear_err->address,
1076 				clear_err->cleared);
1077 	}
1078 	nvdimm_bus_unlock(&nvdimm_bus->dev);
1079 
1080 	if (copy_to_user(p, buf, buf_len))
1081 		rc = -EFAULT;
1082 
1083 	vfree(buf);
1084 	return rc;
1085 
1086  out_unlock:
1087 	nvdimm_bus_unlock(&nvdimm_bus->dev);
1088  out:
1089 	vfree(buf);
1090 	return rc;
1091 }
1092 
1093 static long nd_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1094 {
1095 	long id = (long) file->private_data;
1096 	int rc = -ENXIO, ro;
1097 	struct nvdimm_bus *nvdimm_bus;
1098 
1099 	ro = ((file->f_flags & O_ACCMODE) == O_RDONLY);
1100 	mutex_lock(&nvdimm_bus_list_mutex);
1101 	list_for_each_entry(nvdimm_bus, &nvdimm_bus_list, list) {
1102 		if (nvdimm_bus->id == id) {
1103 			rc = __nd_ioctl(nvdimm_bus, NULL, ro, cmd, arg);
1104 			break;
1105 		}
1106 	}
1107 	mutex_unlock(&nvdimm_bus_list_mutex);
1108 
1109 	return rc;
1110 }
1111 
1112 static int match_dimm(struct device *dev, void *data)
1113 {
1114 	long id = (long) data;
1115 
1116 	if (is_nvdimm(dev)) {
1117 		struct nvdimm *nvdimm = to_nvdimm(dev);
1118 
1119 		return nvdimm->id == id;
1120 	}
1121 
1122 	return 0;
1123 }
1124 
1125 static long nvdimm_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1126 {
1127 	int rc = -ENXIO, ro;
1128 	struct nvdimm_bus *nvdimm_bus;
1129 
1130 	ro = ((file->f_flags & O_ACCMODE) == O_RDONLY);
1131 	mutex_lock(&nvdimm_bus_list_mutex);
1132 	list_for_each_entry(nvdimm_bus, &nvdimm_bus_list, list) {
1133 		struct device *dev = device_find_child(&nvdimm_bus->dev,
1134 				file->private_data, match_dimm);
1135 		struct nvdimm *nvdimm;
1136 
1137 		if (!dev)
1138 			continue;
1139 
1140 		nvdimm = to_nvdimm(dev);
1141 		rc = __nd_ioctl(nvdimm_bus, nvdimm, ro, cmd, arg);
1142 		put_device(dev);
1143 		break;
1144 	}
1145 	mutex_unlock(&nvdimm_bus_list_mutex);
1146 
1147 	return rc;
1148 }
1149 
1150 static int nd_open(struct inode *inode, struct file *file)
1151 {
1152 	long minor = iminor(inode);
1153 
1154 	file->private_data = (void *) minor;
1155 	return 0;
1156 }
1157 
1158 static const struct file_operations nvdimm_bus_fops = {
1159 	.owner = THIS_MODULE,
1160 	.open = nd_open,
1161 	.unlocked_ioctl = nd_ioctl,
1162 	.compat_ioctl = nd_ioctl,
1163 	.llseek = noop_llseek,
1164 };
1165 
1166 static const struct file_operations nvdimm_fops = {
1167 	.owner = THIS_MODULE,
1168 	.open = nd_open,
1169 	.unlocked_ioctl = nvdimm_ioctl,
1170 	.compat_ioctl = nvdimm_ioctl,
1171 	.llseek = noop_llseek,
1172 };
1173 
1174 int __init nvdimm_bus_init(void)
1175 {
1176 	int rc;
1177 
1178 	rc = bus_register(&nvdimm_bus_type);
1179 	if (rc)
1180 		return rc;
1181 
1182 	rc = register_chrdev(0, "ndctl", &nvdimm_bus_fops);
1183 	if (rc < 0)
1184 		goto err_bus_chrdev;
1185 	nvdimm_bus_major = rc;
1186 
1187 	rc = register_chrdev(0, "dimmctl", &nvdimm_fops);
1188 	if (rc < 0)
1189 		goto err_dimm_chrdev;
1190 	nvdimm_major = rc;
1191 
1192 	nd_class = class_create(THIS_MODULE, "nd");
1193 	if (IS_ERR(nd_class)) {
1194 		rc = PTR_ERR(nd_class);
1195 		goto err_class;
1196 	}
1197 
1198 	rc = driver_register(&nd_bus_driver.drv);
1199 	if (rc)
1200 		goto err_nd_bus;
1201 
1202 	return 0;
1203 
1204  err_nd_bus:
1205 	class_destroy(nd_class);
1206  err_class:
1207 	unregister_chrdev(nvdimm_major, "dimmctl");
1208  err_dimm_chrdev:
1209 	unregister_chrdev(nvdimm_bus_major, "ndctl");
1210  err_bus_chrdev:
1211 	bus_unregister(&nvdimm_bus_type);
1212 
1213 	return rc;
1214 }
1215 
1216 void nvdimm_bus_exit(void)
1217 {
1218 	driver_unregister(&nd_bus_driver.drv);
1219 	class_destroy(nd_class);
1220 	unregister_chrdev(nvdimm_bus_major, "ndctl");
1221 	unregister_chrdev(nvdimm_major, "dimmctl");
1222 	bus_unregister(&nvdimm_bus_type);
1223 	ida_destroy(&nd_ida);
1224 }
1225