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1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
4  */
5 #include <linux/scatterlist.h>
6 #include <linux/memregion.h>
7 #include <linux/highmem.h>
8 #include <linux/sched.h>
9 #include <linux/slab.h>
10 #include <linux/hash.h>
11 #include <linux/sort.h>
12 #include <linux/io.h>
13 #include <linux/nd.h>
14 #include "nd-core.h"
15 #include "nd.h"
16 
17 /*
18  * For readq() and writeq() on 32-bit builds, the hi-lo, lo-hi order is
19  * irrelevant.
20  */
21 #include <linux/io-64-nonatomic-hi-lo.h>
22 
23 static DEFINE_PER_CPU(int, flush_idx);
24 
nvdimm_map_flush(struct device * dev,struct nvdimm * nvdimm,int dimm,struct nd_region_data * ndrd)25 static int nvdimm_map_flush(struct device *dev, struct nvdimm *nvdimm, int dimm,
26 		struct nd_region_data *ndrd)
27 {
28 	int i, j;
29 
30 	dev_dbg(dev, "%s: map %d flush address%s\n", nvdimm_name(nvdimm),
31 			nvdimm->num_flush, nvdimm->num_flush == 1 ? "" : "es");
32 	for (i = 0; i < (1 << ndrd->hints_shift); i++) {
33 		struct resource *res = &nvdimm->flush_wpq[i];
34 		unsigned long pfn = PHYS_PFN(res->start);
35 		void __iomem *flush_page;
36 
37 		/* check if flush hints share a page */
38 		for (j = 0; j < i; j++) {
39 			struct resource *res_j = &nvdimm->flush_wpq[j];
40 			unsigned long pfn_j = PHYS_PFN(res_j->start);
41 
42 			if (pfn == pfn_j)
43 				break;
44 		}
45 
46 		if (j < i)
47 			flush_page = (void __iomem *) ((unsigned long)
48 					ndrd_get_flush_wpq(ndrd, dimm, j)
49 					& PAGE_MASK);
50 		else
51 			flush_page = devm_nvdimm_ioremap(dev,
52 					PFN_PHYS(pfn), PAGE_SIZE);
53 		if (!flush_page)
54 			return -ENXIO;
55 		ndrd_set_flush_wpq(ndrd, dimm, i, flush_page
56 				+ (res->start & ~PAGE_MASK));
57 	}
58 
59 	return 0;
60 }
61 
nd_region_activate(struct nd_region * nd_region)62 int nd_region_activate(struct nd_region *nd_region)
63 {
64 	int i, j, num_flush = 0;
65 	struct nd_region_data *ndrd;
66 	struct device *dev = &nd_region->dev;
67 	size_t flush_data_size = sizeof(void *);
68 
69 	nvdimm_bus_lock(&nd_region->dev);
70 	for (i = 0; i < nd_region->ndr_mappings; i++) {
71 		struct nd_mapping *nd_mapping = &nd_region->mapping[i];
72 		struct nvdimm *nvdimm = nd_mapping->nvdimm;
73 
74 		if (test_bit(NDD_SECURITY_OVERWRITE, &nvdimm->flags)) {
75 			nvdimm_bus_unlock(&nd_region->dev);
76 			return -EBUSY;
77 		}
78 
79 		/* at least one null hint slot per-dimm for the "no-hint" case */
80 		flush_data_size += sizeof(void *);
81 		num_flush = min_not_zero(num_flush, nvdimm->num_flush);
82 		if (!nvdimm->num_flush)
83 			continue;
84 		flush_data_size += nvdimm->num_flush * sizeof(void *);
85 	}
86 	nvdimm_bus_unlock(&nd_region->dev);
87 
88 	ndrd = devm_kzalloc(dev, sizeof(*ndrd) + flush_data_size, GFP_KERNEL);
89 	if (!ndrd)
90 		return -ENOMEM;
91 	dev_set_drvdata(dev, ndrd);
92 
93 	if (!num_flush)
94 		return 0;
95 
96 	ndrd->hints_shift = ilog2(num_flush);
97 	for (i = 0; i < nd_region->ndr_mappings; i++) {
98 		struct nd_mapping *nd_mapping = &nd_region->mapping[i];
99 		struct nvdimm *nvdimm = nd_mapping->nvdimm;
100 		int rc = nvdimm_map_flush(&nd_region->dev, nvdimm, i, ndrd);
101 
102 		if (rc)
103 			return rc;
104 	}
105 
106 	/*
107 	 * Clear out entries that are duplicates. This should prevent the
108 	 * extra flushings.
109 	 */
110 	for (i = 0; i < nd_region->ndr_mappings - 1; i++) {
111 		/* ignore if NULL already */
112 		if (!ndrd_get_flush_wpq(ndrd, i, 0))
113 			continue;
114 
115 		for (j = i + 1; j < nd_region->ndr_mappings; j++)
116 			if (ndrd_get_flush_wpq(ndrd, i, 0) ==
117 			    ndrd_get_flush_wpq(ndrd, j, 0))
118 				ndrd_set_flush_wpq(ndrd, j, 0, NULL);
119 	}
120 
121 	return 0;
122 }
123 
nd_region_release(struct device * dev)124 static void nd_region_release(struct device *dev)
125 {
126 	struct nd_region *nd_region = to_nd_region(dev);
127 	u16 i;
128 
129 	for (i = 0; i < nd_region->ndr_mappings; i++) {
130 		struct nd_mapping *nd_mapping = &nd_region->mapping[i];
131 		struct nvdimm *nvdimm = nd_mapping->nvdimm;
132 
133 		put_device(&nvdimm->dev);
134 	}
135 	free_percpu(nd_region->lane);
136 	memregion_free(nd_region->id);
137 	if (is_nd_blk(dev))
138 		kfree(to_nd_blk_region(dev));
139 	else
140 		kfree(nd_region);
141 }
142 
to_nd_region(struct device * dev)143 struct nd_region *to_nd_region(struct device *dev)
144 {
145 	struct nd_region *nd_region = container_of(dev, struct nd_region, dev);
146 
147 	WARN_ON(dev->type->release != nd_region_release);
148 	return nd_region;
149 }
150 EXPORT_SYMBOL_GPL(to_nd_region);
151 
nd_region_dev(struct nd_region * nd_region)152 struct device *nd_region_dev(struct nd_region *nd_region)
153 {
154 	if (!nd_region)
155 		return NULL;
156 	return &nd_region->dev;
157 }
158 EXPORT_SYMBOL_GPL(nd_region_dev);
159 
to_nd_blk_region(struct device * dev)160 struct nd_blk_region *to_nd_blk_region(struct device *dev)
161 {
162 	struct nd_region *nd_region = to_nd_region(dev);
163 
164 	WARN_ON(!is_nd_blk(dev));
165 	return container_of(nd_region, struct nd_blk_region, nd_region);
166 }
167 EXPORT_SYMBOL_GPL(to_nd_blk_region);
168 
nd_region_provider_data(struct nd_region * nd_region)169 void *nd_region_provider_data(struct nd_region *nd_region)
170 {
171 	return nd_region->provider_data;
172 }
173 EXPORT_SYMBOL_GPL(nd_region_provider_data);
174 
nd_blk_region_provider_data(struct nd_blk_region * ndbr)175 void *nd_blk_region_provider_data(struct nd_blk_region *ndbr)
176 {
177 	return ndbr->blk_provider_data;
178 }
179 EXPORT_SYMBOL_GPL(nd_blk_region_provider_data);
180 
nd_blk_region_set_provider_data(struct nd_blk_region * ndbr,void * data)181 void nd_blk_region_set_provider_data(struct nd_blk_region *ndbr, void *data)
182 {
183 	ndbr->blk_provider_data = data;
184 }
185 EXPORT_SYMBOL_GPL(nd_blk_region_set_provider_data);
186 
187 /**
188  * nd_region_to_nstype() - region to an integer namespace type
189  * @nd_region: region-device to interrogate
190  *
191  * This is the 'nstype' attribute of a region as well, an input to the
192  * MODALIAS for namespace devices, and bit number for a nvdimm_bus to match
193  * namespace devices with namespace drivers.
194  */
nd_region_to_nstype(struct nd_region * nd_region)195 int nd_region_to_nstype(struct nd_region *nd_region)
196 {
197 	if (is_memory(&nd_region->dev)) {
198 		u16 i, label;
199 
200 		for (i = 0, label = 0; i < nd_region->ndr_mappings; i++) {
201 			struct nd_mapping *nd_mapping = &nd_region->mapping[i];
202 			struct nvdimm *nvdimm = nd_mapping->nvdimm;
203 
204 			if (test_bit(NDD_LABELING, &nvdimm->flags))
205 				label++;
206 		}
207 		if (label)
208 			return ND_DEVICE_NAMESPACE_PMEM;
209 		else
210 			return ND_DEVICE_NAMESPACE_IO;
211 	} else if (is_nd_blk(&nd_region->dev)) {
212 		return ND_DEVICE_NAMESPACE_BLK;
213 	}
214 
215 	return 0;
216 }
217 EXPORT_SYMBOL(nd_region_to_nstype);
218 
region_size(struct nd_region * nd_region)219 static unsigned long long region_size(struct nd_region *nd_region)
220 {
221 	if (is_memory(&nd_region->dev)) {
222 		return nd_region->ndr_size;
223 	} else if (nd_region->ndr_mappings == 1) {
224 		struct nd_mapping *nd_mapping = &nd_region->mapping[0];
225 
226 		return nd_mapping->size;
227 	}
228 
229 	return 0;
230 }
231 
size_show(struct device * dev,struct device_attribute * attr,char * buf)232 static ssize_t size_show(struct device *dev,
233 		struct device_attribute *attr, char *buf)
234 {
235 	struct nd_region *nd_region = to_nd_region(dev);
236 
237 	return sprintf(buf, "%llu\n", region_size(nd_region));
238 }
239 static DEVICE_ATTR_RO(size);
240 
deep_flush_show(struct device * dev,struct device_attribute * attr,char * buf)241 static ssize_t deep_flush_show(struct device *dev,
242 		struct device_attribute *attr, char *buf)
243 {
244 	struct nd_region *nd_region = to_nd_region(dev);
245 
246 	/*
247 	 * NOTE: in the nvdimm_has_flush() error case this attribute is
248 	 * not visible.
249 	 */
250 	return sprintf(buf, "%d\n", nvdimm_has_flush(nd_region));
251 }
252 
deep_flush_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)253 static ssize_t deep_flush_store(struct device *dev, struct device_attribute *attr,
254 		const char *buf, size_t len)
255 {
256 	bool flush;
257 	int rc = strtobool(buf, &flush);
258 	struct nd_region *nd_region = to_nd_region(dev);
259 
260 	if (rc)
261 		return rc;
262 	if (!flush)
263 		return -EINVAL;
264 	rc = nvdimm_flush(nd_region, NULL);
265 	if (rc)
266 		return rc;
267 
268 	return len;
269 }
270 static DEVICE_ATTR_RW(deep_flush);
271 
mappings_show(struct device * dev,struct device_attribute * attr,char * buf)272 static ssize_t mappings_show(struct device *dev,
273 		struct device_attribute *attr, char *buf)
274 {
275 	struct nd_region *nd_region = to_nd_region(dev);
276 
277 	return sprintf(buf, "%d\n", nd_region->ndr_mappings);
278 }
279 static DEVICE_ATTR_RO(mappings);
280 
nstype_show(struct device * dev,struct device_attribute * attr,char * buf)281 static ssize_t nstype_show(struct device *dev,
282 		struct device_attribute *attr, char *buf)
283 {
284 	struct nd_region *nd_region = to_nd_region(dev);
285 
286 	return sprintf(buf, "%d\n", nd_region_to_nstype(nd_region));
287 }
288 static DEVICE_ATTR_RO(nstype);
289 
set_cookie_show(struct device * dev,struct device_attribute * attr,char * buf)290 static ssize_t set_cookie_show(struct device *dev,
291 		struct device_attribute *attr, char *buf)
292 {
293 	struct nd_region *nd_region = to_nd_region(dev);
294 	struct nd_interleave_set *nd_set = nd_region->nd_set;
295 	ssize_t rc = 0;
296 
297 	if (is_memory(dev) && nd_set)
298 		/* pass, should be precluded by region_visible */;
299 	else
300 		return -ENXIO;
301 
302 	/*
303 	 * The cookie to show depends on which specification of the
304 	 * labels we are using. If there are not labels then default to
305 	 * the v1.1 namespace label cookie definition. To read all this
306 	 * data we need to wait for probing to settle.
307 	 */
308 	nd_device_lock(dev);
309 	nvdimm_bus_lock(dev);
310 	wait_nvdimm_bus_probe_idle(dev);
311 	if (nd_region->ndr_mappings) {
312 		struct nd_mapping *nd_mapping = &nd_region->mapping[0];
313 		struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
314 
315 		if (ndd) {
316 			struct nd_namespace_index *nsindex;
317 
318 			nsindex = to_namespace_index(ndd, ndd->ns_current);
319 			rc = sprintf(buf, "%#llx\n",
320 					nd_region_interleave_set_cookie(nd_region,
321 						nsindex));
322 		}
323 	}
324 	nvdimm_bus_unlock(dev);
325 	nd_device_unlock(dev);
326 
327 	if (rc)
328 		return rc;
329 	return sprintf(buf, "%#llx\n", nd_set->cookie1);
330 }
331 static DEVICE_ATTR_RO(set_cookie);
332 
nd_region_available_dpa(struct nd_region * nd_region)333 resource_size_t nd_region_available_dpa(struct nd_region *nd_region)
334 {
335 	resource_size_t blk_max_overlap = 0, available, overlap;
336 	int i;
337 
338 	WARN_ON(!is_nvdimm_bus_locked(&nd_region->dev));
339 
340  retry:
341 	available = 0;
342 	overlap = blk_max_overlap;
343 	for (i = 0; i < nd_region->ndr_mappings; i++) {
344 		struct nd_mapping *nd_mapping = &nd_region->mapping[i];
345 		struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
346 
347 		/* if a dimm is disabled the available capacity is zero */
348 		if (!ndd)
349 			return 0;
350 
351 		if (is_memory(&nd_region->dev)) {
352 			available += nd_pmem_available_dpa(nd_region,
353 					nd_mapping, &overlap);
354 			if (overlap > blk_max_overlap) {
355 				blk_max_overlap = overlap;
356 				goto retry;
357 			}
358 		} else if (is_nd_blk(&nd_region->dev))
359 			available += nd_blk_available_dpa(nd_region);
360 	}
361 
362 	return available;
363 }
364 
nd_region_allocatable_dpa(struct nd_region * nd_region)365 resource_size_t nd_region_allocatable_dpa(struct nd_region *nd_region)
366 {
367 	resource_size_t available = 0;
368 	int i;
369 
370 	if (is_memory(&nd_region->dev))
371 		available = PHYS_ADDR_MAX;
372 
373 	WARN_ON(!is_nvdimm_bus_locked(&nd_region->dev));
374 	for (i = 0; i < nd_region->ndr_mappings; i++) {
375 		struct nd_mapping *nd_mapping = &nd_region->mapping[i];
376 
377 		if (is_memory(&nd_region->dev))
378 			available = min(available,
379 					nd_pmem_max_contiguous_dpa(nd_region,
380 								   nd_mapping));
381 		else if (is_nd_blk(&nd_region->dev))
382 			available += nd_blk_available_dpa(nd_region);
383 	}
384 	if (is_memory(&nd_region->dev))
385 		return available * nd_region->ndr_mappings;
386 	return available;
387 }
388 
available_size_show(struct device * dev,struct device_attribute * attr,char * buf)389 static ssize_t available_size_show(struct device *dev,
390 		struct device_attribute *attr, char *buf)
391 {
392 	struct nd_region *nd_region = to_nd_region(dev);
393 	unsigned long long available = 0;
394 
395 	/*
396 	 * Flush in-flight updates and grab a snapshot of the available
397 	 * size.  Of course, this value is potentially invalidated the
398 	 * memory nvdimm_bus_lock() is dropped, but that's userspace's
399 	 * problem to not race itself.
400 	 */
401 	nd_device_lock(dev);
402 	nvdimm_bus_lock(dev);
403 	wait_nvdimm_bus_probe_idle(dev);
404 	available = nd_region_available_dpa(nd_region);
405 	nvdimm_bus_unlock(dev);
406 	nd_device_unlock(dev);
407 
408 	return sprintf(buf, "%llu\n", available);
409 }
410 static DEVICE_ATTR_RO(available_size);
411 
max_available_extent_show(struct device * dev,struct device_attribute * attr,char * buf)412 static ssize_t max_available_extent_show(struct device *dev,
413 		struct device_attribute *attr, char *buf)
414 {
415 	struct nd_region *nd_region = to_nd_region(dev);
416 	unsigned long long available = 0;
417 
418 	nd_device_lock(dev);
419 	nvdimm_bus_lock(dev);
420 	wait_nvdimm_bus_probe_idle(dev);
421 	available = nd_region_allocatable_dpa(nd_region);
422 	nvdimm_bus_unlock(dev);
423 	nd_device_unlock(dev);
424 
425 	return sprintf(buf, "%llu\n", available);
426 }
427 static DEVICE_ATTR_RO(max_available_extent);
428 
init_namespaces_show(struct device * dev,struct device_attribute * attr,char * buf)429 static ssize_t init_namespaces_show(struct device *dev,
430 		struct device_attribute *attr, char *buf)
431 {
432 	struct nd_region_data *ndrd = dev_get_drvdata(dev);
433 	ssize_t rc;
434 
435 	nvdimm_bus_lock(dev);
436 	if (ndrd)
437 		rc = sprintf(buf, "%d/%d\n", ndrd->ns_active, ndrd->ns_count);
438 	else
439 		rc = -ENXIO;
440 	nvdimm_bus_unlock(dev);
441 
442 	return rc;
443 }
444 static DEVICE_ATTR_RO(init_namespaces);
445 
namespace_seed_show(struct device * dev,struct device_attribute * attr,char * buf)446 static ssize_t namespace_seed_show(struct device *dev,
447 		struct device_attribute *attr, char *buf)
448 {
449 	struct nd_region *nd_region = to_nd_region(dev);
450 	ssize_t rc;
451 
452 	nvdimm_bus_lock(dev);
453 	if (nd_region->ns_seed)
454 		rc = sprintf(buf, "%s\n", dev_name(nd_region->ns_seed));
455 	else
456 		rc = sprintf(buf, "\n");
457 	nvdimm_bus_unlock(dev);
458 	return rc;
459 }
460 static DEVICE_ATTR_RO(namespace_seed);
461 
btt_seed_show(struct device * dev,struct device_attribute * attr,char * buf)462 static ssize_t btt_seed_show(struct device *dev,
463 		struct device_attribute *attr, char *buf)
464 {
465 	struct nd_region *nd_region = to_nd_region(dev);
466 	ssize_t rc;
467 
468 	nvdimm_bus_lock(dev);
469 	if (nd_region->btt_seed)
470 		rc = sprintf(buf, "%s\n", dev_name(nd_region->btt_seed));
471 	else
472 		rc = sprintf(buf, "\n");
473 	nvdimm_bus_unlock(dev);
474 
475 	return rc;
476 }
477 static DEVICE_ATTR_RO(btt_seed);
478 
pfn_seed_show(struct device * dev,struct device_attribute * attr,char * buf)479 static ssize_t pfn_seed_show(struct device *dev,
480 		struct device_attribute *attr, char *buf)
481 {
482 	struct nd_region *nd_region = to_nd_region(dev);
483 	ssize_t rc;
484 
485 	nvdimm_bus_lock(dev);
486 	if (nd_region->pfn_seed)
487 		rc = sprintf(buf, "%s\n", dev_name(nd_region->pfn_seed));
488 	else
489 		rc = sprintf(buf, "\n");
490 	nvdimm_bus_unlock(dev);
491 
492 	return rc;
493 }
494 static DEVICE_ATTR_RO(pfn_seed);
495 
dax_seed_show(struct device * dev,struct device_attribute * attr,char * buf)496 static ssize_t dax_seed_show(struct device *dev,
497 		struct device_attribute *attr, char *buf)
498 {
499 	struct nd_region *nd_region = to_nd_region(dev);
500 	ssize_t rc;
501 
502 	nvdimm_bus_lock(dev);
503 	if (nd_region->dax_seed)
504 		rc = sprintf(buf, "%s\n", dev_name(nd_region->dax_seed));
505 	else
506 		rc = sprintf(buf, "\n");
507 	nvdimm_bus_unlock(dev);
508 
509 	return rc;
510 }
511 static DEVICE_ATTR_RO(dax_seed);
512 
read_only_show(struct device * dev,struct device_attribute * attr,char * buf)513 static ssize_t read_only_show(struct device *dev,
514 		struct device_attribute *attr, char *buf)
515 {
516 	struct nd_region *nd_region = to_nd_region(dev);
517 
518 	return sprintf(buf, "%d\n", nd_region->ro);
519 }
520 
read_only_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)521 static ssize_t read_only_store(struct device *dev,
522 		struct device_attribute *attr, const char *buf, size_t len)
523 {
524 	bool ro;
525 	int rc = strtobool(buf, &ro);
526 	struct nd_region *nd_region = to_nd_region(dev);
527 
528 	if (rc)
529 		return rc;
530 
531 	nd_region->ro = ro;
532 	return len;
533 }
534 static DEVICE_ATTR_RW(read_only);
535 
align_show(struct device * dev,struct device_attribute * attr,char * buf)536 static ssize_t align_show(struct device *dev,
537 		struct device_attribute *attr, char *buf)
538 {
539 	struct nd_region *nd_region = to_nd_region(dev);
540 
541 	return sprintf(buf, "%#lx\n", nd_region->align);
542 }
543 
align_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)544 static ssize_t align_store(struct device *dev,
545 		struct device_attribute *attr, const char *buf, size_t len)
546 {
547 	struct nd_region *nd_region = to_nd_region(dev);
548 	unsigned long val, dpa;
549 	u32 remainder;
550 	int rc;
551 
552 	rc = kstrtoul(buf, 0, &val);
553 	if (rc)
554 		return rc;
555 
556 	if (!nd_region->ndr_mappings)
557 		return -ENXIO;
558 
559 	/*
560 	 * Ensure space-align is evenly divisible by the region
561 	 * interleave-width because the kernel typically has no facility
562 	 * to determine which DIMM(s), dimm-physical-addresses, would
563 	 * contribute to the tail capacity in system-physical-address
564 	 * space for the namespace.
565 	 */
566 	dpa = div_u64_rem(val, nd_region->ndr_mappings, &remainder);
567 	if (!is_power_of_2(dpa) || dpa < PAGE_SIZE
568 			|| val > region_size(nd_region) || remainder)
569 		return -EINVAL;
570 
571 	/*
572 	 * Given that space allocation consults this value multiple
573 	 * times ensure it does not change for the duration of the
574 	 * allocation.
575 	 */
576 	nvdimm_bus_lock(dev);
577 	nd_region->align = val;
578 	nvdimm_bus_unlock(dev);
579 
580 	return len;
581 }
582 static DEVICE_ATTR_RW(align);
583 
region_badblocks_show(struct device * dev,struct device_attribute * attr,char * buf)584 static ssize_t region_badblocks_show(struct device *dev,
585 		struct device_attribute *attr, char *buf)
586 {
587 	struct nd_region *nd_region = to_nd_region(dev);
588 	ssize_t rc;
589 
590 	nd_device_lock(dev);
591 	if (dev->driver)
592 		rc = badblocks_show(&nd_region->bb, buf, 0);
593 	else
594 		rc = -ENXIO;
595 	nd_device_unlock(dev);
596 
597 	return rc;
598 }
599 static DEVICE_ATTR(badblocks, 0444, region_badblocks_show, NULL);
600 
resource_show(struct device * dev,struct device_attribute * attr,char * buf)601 static ssize_t resource_show(struct device *dev,
602 		struct device_attribute *attr, char *buf)
603 {
604 	struct nd_region *nd_region = to_nd_region(dev);
605 
606 	return sprintf(buf, "%#llx\n", nd_region->ndr_start);
607 }
608 static DEVICE_ATTR_ADMIN_RO(resource);
609 
persistence_domain_show(struct device * dev,struct device_attribute * attr,char * buf)610 static ssize_t persistence_domain_show(struct device *dev,
611 		struct device_attribute *attr, char *buf)
612 {
613 	struct nd_region *nd_region = to_nd_region(dev);
614 
615 	if (test_bit(ND_REGION_PERSIST_CACHE, &nd_region->flags))
616 		return sprintf(buf, "cpu_cache\n");
617 	else if (test_bit(ND_REGION_PERSIST_MEMCTRL, &nd_region->flags))
618 		return sprintf(buf, "memory_controller\n");
619 	else
620 		return sprintf(buf, "\n");
621 }
622 static DEVICE_ATTR_RO(persistence_domain);
623 
624 static struct attribute *nd_region_attributes[] = {
625 	&dev_attr_size.attr,
626 	&dev_attr_align.attr,
627 	&dev_attr_nstype.attr,
628 	&dev_attr_mappings.attr,
629 	&dev_attr_btt_seed.attr,
630 	&dev_attr_pfn_seed.attr,
631 	&dev_attr_dax_seed.attr,
632 	&dev_attr_deep_flush.attr,
633 	&dev_attr_read_only.attr,
634 	&dev_attr_set_cookie.attr,
635 	&dev_attr_available_size.attr,
636 	&dev_attr_max_available_extent.attr,
637 	&dev_attr_namespace_seed.attr,
638 	&dev_attr_init_namespaces.attr,
639 	&dev_attr_badblocks.attr,
640 	&dev_attr_resource.attr,
641 	&dev_attr_persistence_domain.attr,
642 	NULL,
643 };
644 
region_visible(struct kobject * kobj,struct attribute * a,int n)645 static umode_t region_visible(struct kobject *kobj, struct attribute *a, int n)
646 {
647 	struct device *dev = container_of(kobj, typeof(*dev), kobj);
648 	struct nd_region *nd_region = to_nd_region(dev);
649 	struct nd_interleave_set *nd_set = nd_region->nd_set;
650 	int type = nd_region_to_nstype(nd_region);
651 
652 	if (!is_memory(dev) && a == &dev_attr_pfn_seed.attr)
653 		return 0;
654 
655 	if (!is_memory(dev) && a == &dev_attr_dax_seed.attr)
656 		return 0;
657 
658 	if (!is_memory(dev) && a == &dev_attr_badblocks.attr)
659 		return 0;
660 
661 	if (a == &dev_attr_resource.attr && !is_memory(dev))
662 		return 0;
663 
664 	if (a == &dev_attr_deep_flush.attr) {
665 		int has_flush = nvdimm_has_flush(nd_region);
666 
667 		if (has_flush == 1)
668 			return a->mode;
669 		else if (has_flush == 0)
670 			return 0444;
671 		else
672 			return 0;
673 	}
674 
675 	if (a == &dev_attr_persistence_domain.attr) {
676 		if ((nd_region->flags & (BIT(ND_REGION_PERSIST_CACHE)
677 					| BIT(ND_REGION_PERSIST_MEMCTRL))) == 0)
678 			return 0;
679 		return a->mode;
680 	}
681 
682 	if (a == &dev_attr_align.attr)
683 		return a->mode;
684 
685 	if (a != &dev_attr_set_cookie.attr
686 			&& a != &dev_attr_available_size.attr)
687 		return a->mode;
688 
689 	if ((type == ND_DEVICE_NAMESPACE_PMEM
690 				|| type == ND_DEVICE_NAMESPACE_BLK)
691 			&& a == &dev_attr_available_size.attr)
692 		return a->mode;
693 	else if (is_memory(dev) && nd_set)
694 		return a->mode;
695 
696 	return 0;
697 }
698 
mappingN(struct device * dev,char * buf,int n)699 static ssize_t mappingN(struct device *dev, char *buf, int n)
700 {
701 	struct nd_region *nd_region = to_nd_region(dev);
702 	struct nd_mapping *nd_mapping;
703 	struct nvdimm *nvdimm;
704 
705 	if (n >= nd_region->ndr_mappings)
706 		return -ENXIO;
707 	nd_mapping = &nd_region->mapping[n];
708 	nvdimm = nd_mapping->nvdimm;
709 
710 	return sprintf(buf, "%s,%llu,%llu,%d\n", dev_name(&nvdimm->dev),
711 			nd_mapping->start, nd_mapping->size,
712 			nd_mapping->position);
713 }
714 
715 #define REGION_MAPPING(idx) \
716 static ssize_t mapping##idx##_show(struct device *dev,		\
717 		struct device_attribute *attr, char *buf)	\
718 {								\
719 	return mappingN(dev, buf, idx);				\
720 }								\
721 static DEVICE_ATTR_RO(mapping##idx)
722 
723 /*
724  * 32 should be enough for a while, even in the presence of socket
725  * interleave a 32-way interleave set is a degenerate case.
726  */
727 REGION_MAPPING(0);
728 REGION_MAPPING(1);
729 REGION_MAPPING(2);
730 REGION_MAPPING(3);
731 REGION_MAPPING(4);
732 REGION_MAPPING(5);
733 REGION_MAPPING(6);
734 REGION_MAPPING(7);
735 REGION_MAPPING(8);
736 REGION_MAPPING(9);
737 REGION_MAPPING(10);
738 REGION_MAPPING(11);
739 REGION_MAPPING(12);
740 REGION_MAPPING(13);
741 REGION_MAPPING(14);
742 REGION_MAPPING(15);
743 REGION_MAPPING(16);
744 REGION_MAPPING(17);
745 REGION_MAPPING(18);
746 REGION_MAPPING(19);
747 REGION_MAPPING(20);
748 REGION_MAPPING(21);
749 REGION_MAPPING(22);
750 REGION_MAPPING(23);
751 REGION_MAPPING(24);
752 REGION_MAPPING(25);
753 REGION_MAPPING(26);
754 REGION_MAPPING(27);
755 REGION_MAPPING(28);
756 REGION_MAPPING(29);
757 REGION_MAPPING(30);
758 REGION_MAPPING(31);
759 
mapping_visible(struct kobject * kobj,struct attribute * a,int n)760 static umode_t mapping_visible(struct kobject *kobj, struct attribute *a, int n)
761 {
762 	struct device *dev = container_of(kobj, struct device, kobj);
763 	struct nd_region *nd_region = to_nd_region(dev);
764 
765 	if (n < nd_region->ndr_mappings)
766 		return a->mode;
767 	return 0;
768 }
769 
770 static struct attribute *mapping_attributes[] = {
771 	&dev_attr_mapping0.attr,
772 	&dev_attr_mapping1.attr,
773 	&dev_attr_mapping2.attr,
774 	&dev_attr_mapping3.attr,
775 	&dev_attr_mapping4.attr,
776 	&dev_attr_mapping5.attr,
777 	&dev_attr_mapping6.attr,
778 	&dev_attr_mapping7.attr,
779 	&dev_attr_mapping8.attr,
780 	&dev_attr_mapping9.attr,
781 	&dev_attr_mapping10.attr,
782 	&dev_attr_mapping11.attr,
783 	&dev_attr_mapping12.attr,
784 	&dev_attr_mapping13.attr,
785 	&dev_attr_mapping14.attr,
786 	&dev_attr_mapping15.attr,
787 	&dev_attr_mapping16.attr,
788 	&dev_attr_mapping17.attr,
789 	&dev_attr_mapping18.attr,
790 	&dev_attr_mapping19.attr,
791 	&dev_attr_mapping20.attr,
792 	&dev_attr_mapping21.attr,
793 	&dev_attr_mapping22.attr,
794 	&dev_attr_mapping23.attr,
795 	&dev_attr_mapping24.attr,
796 	&dev_attr_mapping25.attr,
797 	&dev_attr_mapping26.attr,
798 	&dev_attr_mapping27.attr,
799 	&dev_attr_mapping28.attr,
800 	&dev_attr_mapping29.attr,
801 	&dev_attr_mapping30.attr,
802 	&dev_attr_mapping31.attr,
803 	NULL,
804 };
805 
806 static const struct attribute_group nd_mapping_attribute_group = {
807 	.is_visible = mapping_visible,
808 	.attrs = mapping_attributes,
809 };
810 
811 static const struct attribute_group nd_region_attribute_group = {
812 	.attrs = nd_region_attributes,
813 	.is_visible = region_visible,
814 };
815 
816 static const struct attribute_group *nd_region_attribute_groups[] = {
817 	&nd_device_attribute_group,
818 	&nd_region_attribute_group,
819 	&nd_numa_attribute_group,
820 	&nd_mapping_attribute_group,
821 	NULL,
822 };
823 
824 static const struct device_type nd_blk_device_type = {
825 	.name = "nd_blk",
826 	.release = nd_region_release,
827 	.groups = nd_region_attribute_groups,
828 };
829 
830 static const struct device_type nd_pmem_device_type = {
831 	.name = "nd_pmem",
832 	.release = nd_region_release,
833 	.groups = nd_region_attribute_groups,
834 };
835 
836 static const struct device_type nd_volatile_device_type = {
837 	.name = "nd_volatile",
838 	.release = nd_region_release,
839 	.groups = nd_region_attribute_groups,
840 };
841 
is_nd_pmem(struct device * dev)842 bool is_nd_pmem(struct device *dev)
843 {
844 	return dev ? dev->type == &nd_pmem_device_type : false;
845 }
846 
is_nd_blk(struct device * dev)847 bool is_nd_blk(struct device *dev)
848 {
849 	return dev ? dev->type == &nd_blk_device_type : false;
850 }
851 
is_nd_volatile(struct device * dev)852 bool is_nd_volatile(struct device *dev)
853 {
854 	return dev ? dev->type == &nd_volatile_device_type : false;
855 }
856 
nd_region_interleave_set_cookie(struct nd_region * nd_region,struct nd_namespace_index * nsindex)857 u64 nd_region_interleave_set_cookie(struct nd_region *nd_region,
858 		struct nd_namespace_index *nsindex)
859 {
860 	struct nd_interleave_set *nd_set = nd_region->nd_set;
861 
862 	if (!nd_set)
863 		return 0;
864 
865 	if (nsindex && __le16_to_cpu(nsindex->major) == 1
866 			&& __le16_to_cpu(nsindex->minor) == 1)
867 		return nd_set->cookie1;
868 	return nd_set->cookie2;
869 }
870 
nd_region_interleave_set_altcookie(struct nd_region * nd_region)871 u64 nd_region_interleave_set_altcookie(struct nd_region *nd_region)
872 {
873 	struct nd_interleave_set *nd_set = nd_region->nd_set;
874 
875 	if (nd_set)
876 		return nd_set->altcookie;
877 	return 0;
878 }
879 
nd_mapping_free_labels(struct nd_mapping * nd_mapping)880 void nd_mapping_free_labels(struct nd_mapping *nd_mapping)
881 {
882 	struct nd_label_ent *label_ent, *e;
883 
884 	lockdep_assert_held(&nd_mapping->lock);
885 	list_for_each_entry_safe(label_ent, e, &nd_mapping->labels, list) {
886 		list_del(&label_ent->list);
887 		kfree(label_ent);
888 	}
889 }
890 
891 /*
892  * When a namespace is activated create new seeds for the next
893  * namespace, or namespace-personality to be configured.
894  */
nd_region_advance_seeds(struct nd_region * nd_region,struct device * dev)895 void nd_region_advance_seeds(struct nd_region *nd_region, struct device *dev)
896 {
897 	nvdimm_bus_lock(dev);
898 	if (nd_region->ns_seed == dev) {
899 		nd_region_create_ns_seed(nd_region);
900 	} else if (is_nd_btt(dev)) {
901 		struct nd_btt *nd_btt = to_nd_btt(dev);
902 
903 		if (nd_region->btt_seed == dev)
904 			nd_region_create_btt_seed(nd_region);
905 		if (nd_region->ns_seed == &nd_btt->ndns->dev)
906 			nd_region_create_ns_seed(nd_region);
907 	} else if (is_nd_pfn(dev)) {
908 		struct nd_pfn *nd_pfn = to_nd_pfn(dev);
909 
910 		if (nd_region->pfn_seed == dev)
911 			nd_region_create_pfn_seed(nd_region);
912 		if (nd_region->ns_seed == &nd_pfn->ndns->dev)
913 			nd_region_create_ns_seed(nd_region);
914 	} else if (is_nd_dax(dev)) {
915 		struct nd_dax *nd_dax = to_nd_dax(dev);
916 
917 		if (nd_region->dax_seed == dev)
918 			nd_region_create_dax_seed(nd_region);
919 		if (nd_region->ns_seed == &nd_dax->nd_pfn.ndns->dev)
920 			nd_region_create_ns_seed(nd_region);
921 	}
922 	nvdimm_bus_unlock(dev);
923 }
924 
nd_blk_region_init(struct nd_region * nd_region)925 int nd_blk_region_init(struct nd_region *nd_region)
926 {
927 	struct device *dev = &nd_region->dev;
928 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
929 
930 	if (!is_nd_blk(dev))
931 		return 0;
932 
933 	if (nd_region->ndr_mappings < 1) {
934 		dev_dbg(dev, "invalid BLK region\n");
935 		return -ENXIO;
936 	}
937 
938 	return to_nd_blk_region(dev)->enable(nvdimm_bus, dev);
939 }
940 
941 /**
942  * nd_region_acquire_lane - allocate and lock a lane
943  * @nd_region: region id and number of lanes possible
944  *
945  * A lane correlates to a BLK-data-window and/or a log slot in the BTT.
946  * We optimize for the common case where there are 256 lanes, one
947  * per-cpu.  For larger systems we need to lock to share lanes.  For now
948  * this implementation assumes the cost of maintaining an allocator for
949  * free lanes is on the order of the lock hold time, so it implements a
950  * static lane = cpu % num_lanes mapping.
951  *
952  * In the case of a BTT instance on top of a BLK namespace a lane may be
953  * acquired recursively.  We lock on the first instance.
954  *
955  * In the case of a BTT instance on top of PMEM, we only acquire a lane
956  * for the BTT metadata updates.
957  */
nd_region_acquire_lane(struct nd_region * nd_region)958 unsigned int nd_region_acquire_lane(struct nd_region *nd_region)
959 {
960 	unsigned int cpu, lane;
961 
962 	cpu = get_cpu();
963 	if (nd_region->num_lanes < nr_cpu_ids) {
964 		struct nd_percpu_lane *ndl_lock, *ndl_count;
965 
966 		lane = cpu % nd_region->num_lanes;
967 		ndl_count = per_cpu_ptr(nd_region->lane, cpu);
968 		ndl_lock = per_cpu_ptr(nd_region->lane, lane);
969 		if (ndl_count->count++ == 0)
970 			spin_lock(&ndl_lock->lock);
971 	} else
972 		lane = cpu;
973 
974 	return lane;
975 }
976 EXPORT_SYMBOL(nd_region_acquire_lane);
977 
nd_region_release_lane(struct nd_region * nd_region,unsigned int lane)978 void nd_region_release_lane(struct nd_region *nd_region, unsigned int lane)
979 {
980 	if (nd_region->num_lanes < nr_cpu_ids) {
981 		unsigned int cpu = get_cpu();
982 		struct nd_percpu_lane *ndl_lock, *ndl_count;
983 
984 		ndl_count = per_cpu_ptr(nd_region->lane, cpu);
985 		ndl_lock = per_cpu_ptr(nd_region->lane, lane);
986 		if (--ndl_count->count == 0)
987 			spin_unlock(&ndl_lock->lock);
988 		put_cpu();
989 	}
990 	put_cpu();
991 }
992 EXPORT_SYMBOL(nd_region_release_lane);
993 
994 /*
995  * PowerPC requires this alignment for memremap_pages(). All other archs
996  * should be ok with SUBSECTION_SIZE (see memremap_compat_align()).
997  */
998 #define MEMREMAP_COMPAT_ALIGN_MAX SZ_16M
999 
default_align(struct nd_region * nd_region)1000 static unsigned long default_align(struct nd_region *nd_region)
1001 {
1002 	unsigned long align;
1003 	int i, mappings;
1004 	u32 remainder;
1005 
1006 	if (is_nd_blk(&nd_region->dev))
1007 		align = PAGE_SIZE;
1008 	else
1009 		align = MEMREMAP_COMPAT_ALIGN_MAX;
1010 
1011 	for (i = 0; i < nd_region->ndr_mappings; i++) {
1012 		struct nd_mapping *nd_mapping = &nd_region->mapping[i];
1013 		struct nvdimm *nvdimm = nd_mapping->nvdimm;
1014 
1015 		if (test_bit(NDD_ALIASING, &nvdimm->flags)) {
1016 			align = MEMREMAP_COMPAT_ALIGN_MAX;
1017 			break;
1018 		}
1019 	}
1020 
1021 	if (nd_region->ndr_size < MEMREMAP_COMPAT_ALIGN_MAX)
1022 		align = PAGE_SIZE;
1023 
1024 	mappings = max_t(u16, 1, nd_region->ndr_mappings);
1025 	div_u64_rem(align, mappings, &remainder);
1026 	if (remainder)
1027 		align *= mappings;
1028 
1029 	return align;
1030 }
1031 
nd_region_create(struct nvdimm_bus * nvdimm_bus,struct nd_region_desc * ndr_desc,const struct device_type * dev_type,const char * caller)1032 static struct nd_region *nd_region_create(struct nvdimm_bus *nvdimm_bus,
1033 		struct nd_region_desc *ndr_desc,
1034 		const struct device_type *dev_type, const char *caller)
1035 {
1036 	struct nd_region *nd_region;
1037 	struct device *dev;
1038 	void *region_buf;
1039 	unsigned int i;
1040 	int ro = 0;
1041 
1042 	for (i = 0; i < ndr_desc->num_mappings; i++) {
1043 		struct nd_mapping_desc *mapping = &ndr_desc->mapping[i];
1044 		struct nvdimm *nvdimm = mapping->nvdimm;
1045 
1046 		if ((mapping->start | mapping->size) % PAGE_SIZE) {
1047 			dev_err(&nvdimm_bus->dev,
1048 				"%s: %s mapping%d is not %ld aligned\n",
1049 				caller, dev_name(&nvdimm->dev), i, PAGE_SIZE);
1050 			return NULL;
1051 		}
1052 
1053 		if (test_bit(NDD_UNARMED, &nvdimm->flags))
1054 			ro = 1;
1055 
1056 		if (test_bit(NDD_NOBLK, &nvdimm->flags)
1057 				&& dev_type == &nd_blk_device_type) {
1058 			dev_err(&nvdimm_bus->dev, "%s: %s mapping%d is not BLK capable\n",
1059 					caller, dev_name(&nvdimm->dev), i);
1060 			return NULL;
1061 		}
1062 	}
1063 
1064 	if (dev_type == &nd_blk_device_type) {
1065 		struct nd_blk_region_desc *ndbr_desc;
1066 		struct nd_blk_region *ndbr;
1067 
1068 		ndbr_desc = to_blk_region_desc(ndr_desc);
1069 		ndbr = kzalloc(sizeof(*ndbr) + sizeof(struct nd_mapping)
1070 				* ndr_desc->num_mappings,
1071 				GFP_KERNEL);
1072 		if (ndbr) {
1073 			nd_region = &ndbr->nd_region;
1074 			ndbr->enable = ndbr_desc->enable;
1075 			ndbr->do_io = ndbr_desc->do_io;
1076 		}
1077 		region_buf = ndbr;
1078 	} else {
1079 		nd_region = kzalloc(struct_size(nd_region, mapping,
1080 						ndr_desc->num_mappings),
1081 				    GFP_KERNEL);
1082 		region_buf = nd_region;
1083 	}
1084 
1085 	if (!region_buf)
1086 		return NULL;
1087 	nd_region->id = memregion_alloc(GFP_KERNEL);
1088 	if (nd_region->id < 0)
1089 		goto err_id;
1090 
1091 	nd_region->lane = alloc_percpu(struct nd_percpu_lane);
1092 	if (!nd_region->lane)
1093 		goto err_percpu;
1094 
1095         for (i = 0; i < nr_cpu_ids; i++) {
1096 		struct nd_percpu_lane *ndl;
1097 
1098 		ndl = per_cpu_ptr(nd_region->lane, i);
1099 		spin_lock_init(&ndl->lock);
1100 		ndl->count = 0;
1101 	}
1102 
1103 	for (i = 0; i < ndr_desc->num_mappings; i++) {
1104 		struct nd_mapping_desc *mapping = &ndr_desc->mapping[i];
1105 		struct nvdimm *nvdimm = mapping->nvdimm;
1106 
1107 		nd_region->mapping[i].nvdimm = nvdimm;
1108 		nd_region->mapping[i].start = mapping->start;
1109 		nd_region->mapping[i].size = mapping->size;
1110 		nd_region->mapping[i].position = mapping->position;
1111 		INIT_LIST_HEAD(&nd_region->mapping[i].labels);
1112 		mutex_init(&nd_region->mapping[i].lock);
1113 
1114 		get_device(&nvdimm->dev);
1115 	}
1116 	nd_region->ndr_mappings = ndr_desc->num_mappings;
1117 	nd_region->provider_data = ndr_desc->provider_data;
1118 	nd_region->nd_set = ndr_desc->nd_set;
1119 	nd_region->num_lanes = ndr_desc->num_lanes;
1120 	nd_region->flags = ndr_desc->flags;
1121 	nd_region->ro = ro;
1122 	nd_region->numa_node = ndr_desc->numa_node;
1123 	nd_region->target_node = ndr_desc->target_node;
1124 	ida_init(&nd_region->ns_ida);
1125 	ida_init(&nd_region->btt_ida);
1126 	ida_init(&nd_region->pfn_ida);
1127 	ida_init(&nd_region->dax_ida);
1128 	dev = &nd_region->dev;
1129 	dev_set_name(dev, "region%d", nd_region->id);
1130 	dev->parent = &nvdimm_bus->dev;
1131 	dev->type = dev_type;
1132 	dev->groups = ndr_desc->attr_groups;
1133 	dev->of_node = ndr_desc->of_node;
1134 	nd_region->ndr_size = resource_size(ndr_desc->res);
1135 	nd_region->ndr_start = ndr_desc->res->start;
1136 	nd_region->align = default_align(nd_region);
1137 	if (ndr_desc->flush)
1138 		nd_region->flush = ndr_desc->flush;
1139 	else
1140 		nd_region->flush = NULL;
1141 
1142 	nd_device_register(dev);
1143 
1144 	return nd_region;
1145 
1146  err_percpu:
1147 	memregion_free(nd_region->id);
1148  err_id:
1149 	kfree(region_buf);
1150 	return NULL;
1151 }
1152 
nvdimm_pmem_region_create(struct nvdimm_bus * nvdimm_bus,struct nd_region_desc * ndr_desc)1153 struct nd_region *nvdimm_pmem_region_create(struct nvdimm_bus *nvdimm_bus,
1154 		struct nd_region_desc *ndr_desc)
1155 {
1156 	ndr_desc->num_lanes = ND_MAX_LANES;
1157 	return nd_region_create(nvdimm_bus, ndr_desc, &nd_pmem_device_type,
1158 			__func__);
1159 }
1160 EXPORT_SYMBOL_GPL(nvdimm_pmem_region_create);
1161 
nvdimm_blk_region_create(struct nvdimm_bus * nvdimm_bus,struct nd_region_desc * ndr_desc)1162 struct nd_region *nvdimm_blk_region_create(struct nvdimm_bus *nvdimm_bus,
1163 		struct nd_region_desc *ndr_desc)
1164 {
1165 	if (ndr_desc->num_mappings > 1)
1166 		return NULL;
1167 	ndr_desc->num_lanes = min(ndr_desc->num_lanes, ND_MAX_LANES);
1168 	return nd_region_create(nvdimm_bus, ndr_desc, &nd_blk_device_type,
1169 			__func__);
1170 }
1171 EXPORT_SYMBOL_GPL(nvdimm_blk_region_create);
1172 
nvdimm_volatile_region_create(struct nvdimm_bus * nvdimm_bus,struct nd_region_desc * ndr_desc)1173 struct nd_region *nvdimm_volatile_region_create(struct nvdimm_bus *nvdimm_bus,
1174 		struct nd_region_desc *ndr_desc)
1175 {
1176 	ndr_desc->num_lanes = ND_MAX_LANES;
1177 	return nd_region_create(nvdimm_bus, ndr_desc, &nd_volatile_device_type,
1178 			__func__);
1179 }
1180 EXPORT_SYMBOL_GPL(nvdimm_volatile_region_create);
1181 
nvdimm_flush(struct nd_region * nd_region,struct bio * bio)1182 int nvdimm_flush(struct nd_region *nd_region, struct bio *bio)
1183 {
1184 	int rc = 0;
1185 
1186 	if (!nd_region->flush)
1187 		rc = generic_nvdimm_flush(nd_region);
1188 	else {
1189 		if (nd_region->flush(nd_region, bio))
1190 			rc = -EIO;
1191 	}
1192 
1193 	return rc;
1194 }
1195 /**
1196  * nvdimm_flush - flush any posted write queues between the cpu and pmem media
1197  * @nd_region: blk or interleaved pmem region
1198  */
generic_nvdimm_flush(struct nd_region * nd_region)1199 int generic_nvdimm_flush(struct nd_region *nd_region)
1200 {
1201 	struct nd_region_data *ndrd = dev_get_drvdata(&nd_region->dev);
1202 	int i, idx;
1203 
1204 	/*
1205 	 * Try to encourage some diversity in flush hint addresses
1206 	 * across cpus assuming a limited number of flush hints.
1207 	 */
1208 	idx = this_cpu_read(flush_idx);
1209 	idx = this_cpu_add_return(flush_idx, hash_32(current->pid + idx, 8));
1210 
1211 	/*
1212 	 * The pmem_wmb() is needed to 'sfence' all
1213 	 * previous writes such that they are architecturally visible for
1214 	 * the platform buffer flush. Note that we've already arranged for pmem
1215 	 * writes to avoid the cache via memcpy_flushcache().  The final
1216 	 * wmb() ensures ordering for the NVDIMM flush write.
1217 	 */
1218 	pmem_wmb();
1219 	for (i = 0; i < nd_region->ndr_mappings; i++)
1220 		if (ndrd_get_flush_wpq(ndrd, i, 0))
1221 			writeq(1, ndrd_get_flush_wpq(ndrd, i, idx));
1222 	wmb();
1223 
1224 	return 0;
1225 }
1226 EXPORT_SYMBOL_GPL(nvdimm_flush);
1227 
1228 /**
1229  * nvdimm_has_flush - determine write flushing requirements
1230  * @nd_region: blk or interleaved pmem region
1231  *
1232  * Returns 1 if writes require flushing
1233  * Returns 0 if writes do not require flushing
1234  * Returns -ENXIO if flushing capability can not be determined
1235  */
nvdimm_has_flush(struct nd_region * nd_region)1236 int nvdimm_has_flush(struct nd_region *nd_region)
1237 {
1238 	int i;
1239 
1240 	/* no nvdimm or pmem api == flushing capability unknown */
1241 	if (nd_region->ndr_mappings == 0
1242 			|| !IS_ENABLED(CONFIG_ARCH_HAS_PMEM_API))
1243 		return -ENXIO;
1244 
1245 	/* Test if an explicit flush function is defined */
1246 	if (test_bit(ND_REGION_ASYNC, &nd_region->flags) && nd_region->flush)
1247 		return 1;
1248 
1249 	/* Test if any flush hints for the region are available */
1250 	for (i = 0; i < nd_region->ndr_mappings; i++) {
1251 		struct nd_mapping *nd_mapping = &nd_region->mapping[i];
1252 		struct nvdimm *nvdimm = nd_mapping->nvdimm;
1253 
1254 		/* flush hints present / available */
1255 		if (nvdimm->num_flush)
1256 			return 1;
1257 	}
1258 
1259 	/*
1260 	 * The platform defines dimm devices without hints nor explicit flush,
1261 	 * assume platform persistence mechanism like ADR
1262 	 */
1263 	return 0;
1264 }
1265 EXPORT_SYMBOL_GPL(nvdimm_has_flush);
1266 
nvdimm_has_cache(struct nd_region * nd_region)1267 int nvdimm_has_cache(struct nd_region *nd_region)
1268 {
1269 	return is_nd_pmem(&nd_region->dev) &&
1270 		!test_bit(ND_REGION_PERSIST_CACHE, &nd_region->flags);
1271 }
1272 EXPORT_SYMBOL_GPL(nvdimm_has_cache);
1273 
is_nvdimm_sync(struct nd_region * nd_region)1274 bool is_nvdimm_sync(struct nd_region *nd_region)
1275 {
1276 	if (is_nd_volatile(&nd_region->dev))
1277 		return true;
1278 
1279 	return is_nd_pmem(&nd_region->dev) &&
1280 		!test_bit(ND_REGION_ASYNC, &nd_region->flags);
1281 }
1282 EXPORT_SYMBOL_GPL(is_nvdimm_sync);
1283 
1284 struct conflict_context {
1285 	struct nd_region *nd_region;
1286 	resource_size_t start, size;
1287 };
1288 
region_conflict(struct device * dev,void * data)1289 static int region_conflict(struct device *dev, void *data)
1290 {
1291 	struct nd_region *nd_region;
1292 	struct conflict_context *ctx = data;
1293 	resource_size_t res_end, region_end, region_start;
1294 
1295 	if (!is_memory(dev))
1296 		return 0;
1297 
1298 	nd_region = to_nd_region(dev);
1299 	if (nd_region == ctx->nd_region)
1300 		return 0;
1301 
1302 	res_end = ctx->start + ctx->size;
1303 	region_start = nd_region->ndr_start;
1304 	region_end = region_start + nd_region->ndr_size;
1305 	if (ctx->start >= region_start && ctx->start < region_end)
1306 		return -EBUSY;
1307 	if (res_end > region_start && res_end <= region_end)
1308 		return -EBUSY;
1309 	return 0;
1310 }
1311 
nd_region_conflict(struct nd_region * nd_region,resource_size_t start,resource_size_t size)1312 int nd_region_conflict(struct nd_region *nd_region, resource_size_t start,
1313 		resource_size_t size)
1314 {
1315 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&nd_region->dev);
1316 	struct conflict_context ctx = {
1317 		.nd_region = nd_region,
1318 		.start = start,
1319 		.size = size,
1320 	};
1321 
1322 	return device_for_each_child(&nvdimm_bus->dev, &ctx, region_conflict);
1323 }
1324