1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright(c) 2013-2016 Intel Corporation. All rights reserved.
4 */
5 #include <linux/memremap.h>
6 #include <linux/blkdev.h>
7 #include <linux/device.h>
8 #include <linux/sizes.h>
9 #include <linux/slab.h>
10 #include <linux/fs.h>
11 #include <linux/mm.h>
12 #include "nd-core.h"
13 #include "pfn.h"
14 #include "nd.h"
15
16 static const bool page_struct_override = IS_ENABLED(CONFIG_NVDIMM_KMSAN);
17
nd_pfn_release(struct device * dev)18 static void nd_pfn_release(struct device *dev)
19 {
20 struct nd_region *nd_region = to_nd_region(dev->parent);
21 struct nd_pfn *nd_pfn = to_nd_pfn(dev);
22
23 dev_dbg(dev, "trace\n");
24 nd_detach_ndns(&nd_pfn->dev, &nd_pfn->ndns);
25 ida_simple_remove(&nd_region->pfn_ida, nd_pfn->id);
26 kfree(nd_pfn->uuid);
27 kfree(nd_pfn);
28 }
29
to_nd_pfn(struct device * dev)30 struct nd_pfn *to_nd_pfn(struct device *dev)
31 {
32 struct nd_pfn *nd_pfn = container_of(dev, struct nd_pfn, dev);
33
34 WARN_ON(!is_nd_pfn(dev));
35 return nd_pfn;
36 }
37 EXPORT_SYMBOL(to_nd_pfn);
38
mode_show(struct device * dev,struct device_attribute * attr,char * buf)39 static ssize_t mode_show(struct device *dev,
40 struct device_attribute *attr, char *buf)
41 {
42 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
43
44 switch (nd_pfn->mode) {
45 case PFN_MODE_RAM:
46 return sprintf(buf, "ram\n");
47 case PFN_MODE_PMEM:
48 return sprintf(buf, "pmem\n");
49 default:
50 return sprintf(buf, "none\n");
51 }
52 }
53
mode_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)54 static ssize_t mode_store(struct device *dev,
55 struct device_attribute *attr, const char *buf, size_t len)
56 {
57 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
58 ssize_t rc = 0;
59
60 device_lock(dev);
61 nvdimm_bus_lock(dev);
62 if (dev->driver)
63 rc = -EBUSY;
64 else {
65 size_t n = len - 1;
66
67 if (strncmp(buf, "pmem\n", n) == 0
68 || strncmp(buf, "pmem", n) == 0) {
69 nd_pfn->mode = PFN_MODE_PMEM;
70 } else if (strncmp(buf, "ram\n", n) == 0
71 || strncmp(buf, "ram", n) == 0)
72 nd_pfn->mode = PFN_MODE_RAM;
73 else if (strncmp(buf, "none\n", n) == 0
74 || strncmp(buf, "none", n) == 0)
75 nd_pfn->mode = PFN_MODE_NONE;
76 else
77 rc = -EINVAL;
78 }
79 dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
80 buf[len - 1] == '\n' ? "" : "\n");
81 nvdimm_bus_unlock(dev);
82 device_unlock(dev);
83
84 return rc ? rc : len;
85 }
86 static DEVICE_ATTR_RW(mode);
87
align_show(struct device * dev,struct device_attribute * attr,char * buf)88 static ssize_t align_show(struct device *dev,
89 struct device_attribute *attr, char *buf)
90 {
91 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
92
93 return sprintf(buf, "%ld\n", nd_pfn->align);
94 }
95
nd_pfn_supported_alignments(unsigned long * alignments)96 static unsigned long *nd_pfn_supported_alignments(unsigned long *alignments)
97 {
98
99 alignments[0] = PAGE_SIZE;
100
101 if (has_transparent_hugepage()) {
102 alignments[1] = HPAGE_PMD_SIZE;
103 if (IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD))
104 alignments[2] = HPAGE_PUD_SIZE;
105 }
106
107 return alignments;
108 }
109
110 /*
111 * Use pmd mapping if supported as default alignment
112 */
nd_pfn_default_alignment(void)113 static unsigned long nd_pfn_default_alignment(void)
114 {
115
116 if (has_transparent_hugepage())
117 return HPAGE_PMD_SIZE;
118 return PAGE_SIZE;
119 }
120
align_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)121 static ssize_t align_store(struct device *dev,
122 struct device_attribute *attr, const char *buf, size_t len)
123 {
124 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
125 unsigned long aligns[MAX_NVDIMM_ALIGN] = { [0] = 0, };
126 ssize_t rc;
127
128 device_lock(dev);
129 nvdimm_bus_lock(dev);
130 rc = nd_size_select_store(dev, buf, &nd_pfn->align,
131 nd_pfn_supported_alignments(aligns));
132 dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
133 buf[len - 1] == '\n' ? "" : "\n");
134 nvdimm_bus_unlock(dev);
135 device_unlock(dev);
136
137 return rc ? rc : len;
138 }
139 static DEVICE_ATTR_RW(align);
140
uuid_show(struct device * dev,struct device_attribute * attr,char * buf)141 static ssize_t uuid_show(struct device *dev,
142 struct device_attribute *attr, char *buf)
143 {
144 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
145
146 if (nd_pfn->uuid)
147 return sprintf(buf, "%pUb\n", nd_pfn->uuid);
148 return sprintf(buf, "\n");
149 }
150
uuid_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)151 static ssize_t uuid_store(struct device *dev,
152 struct device_attribute *attr, const char *buf, size_t len)
153 {
154 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
155 ssize_t rc;
156
157 device_lock(dev);
158 rc = nd_uuid_store(dev, &nd_pfn->uuid, buf, len);
159 dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
160 buf[len - 1] == '\n' ? "" : "\n");
161 device_unlock(dev);
162
163 return rc ? rc : len;
164 }
165 static DEVICE_ATTR_RW(uuid);
166
namespace_show(struct device * dev,struct device_attribute * attr,char * buf)167 static ssize_t namespace_show(struct device *dev,
168 struct device_attribute *attr, char *buf)
169 {
170 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
171 ssize_t rc;
172
173 nvdimm_bus_lock(dev);
174 rc = sprintf(buf, "%s\n", nd_pfn->ndns
175 ? dev_name(&nd_pfn->ndns->dev) : "");
176 nvdimm_bus_unlock(dev);
177 return rc;
178 }
179
namespace_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)180 static ssize_t namespace_store(struct device *dev,
181 struct device_attribute *attr, const char *buf, size_t len)
182 {
183 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
184 ssize_t rc;
185
186 device_lock(dev);
187 nvdimm_bus_lock(dev);
188 rc = nd_namespace_store(dev, &nd_pfn->ndns, buf, len);
189 dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
190 buf[len - 1] == '\n' ? "" : "\n");
191 nvdimm_bus_unlock(dev);
192 device_unlock(dev);
193
194 return rc;
195 }
196 static DEVICE_ATTR_RW(namespace);
197
resource_show(struct device * dev,struct device_attribute * attr,char * buf)198 static ssize_t resource_show(struct device *dev,
199 struct device_attribute *attr, char *buf)
200 {
201 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
202 ssize_t rc;
203
204 device_lock(dev);
205 if (dev->driver) {
206 struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb;
207 u64 offset = __le64_to_cpu(pfn_sb->dataoff);
208 struct nd_namespace_common *ndns = nd_pfn->ndns;
209 u32 start_pad = __le32_to_cpu(pfn_sb->start_pad);
210 struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
211
212 rc = sprintf(buf, "%#llx\n", (unsigned long long) nsio->res.start
213 + start_pad + offset);
214 } else {
215 /* no address to convey if the pfn instance is disabled */
216 rc = -ENXIO;
217 }
218 device_unlock(dev);
219
220 return rc;
221 }
222 static DEVICE_ATTR_ADMIN_RO(resource);
223
size_show(struct device * dev,struct device_attribute * attr,char * buf)224 static ssize_t size_show(struct device *dev,
225 struct device_attribute *attr, char *buf)
226 {
227 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
228 ssize_t rc;
229
230 device_lock(dev);
231 if (dev->driver) {
232 struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb;
233 u64 offset = __le64_to_cpu(pfn_sb->dataoff);
234 struct nd_namespace_common *ndns = nd_pfn->ndns;
235 u32 start_pad = __le32_to_cpu(pfn_sb->start_pad);
236 u32 end_trunc = __le32_to_cpu(pfn_sb->end_trunc);
237 struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
238
239 rc = sprintf(buf, "%llu\n", (unsigned long long)
240 resource_size(&nsio->res) - start_pad
241 - end_trunc - offset);
242 } else {
243 /* no size to convey if the pfn instance is disabled */
244 rc = -ENXIO;
245 }
246 device_unlock(dev);
247
248 return rc;
249 }
250 static DEVICE_ATTR_RO(size);
251
supported_alignments_show(struct device * dev,struct device_attribute * attr,char * buf)252 static ssize_t supported_alignments_show(struct device *dev,
253 struct device_attribute *attr, char *buf)
254 {
255 unsigned long aligns[MAX_NVDIMM_ALIGN] = { [0] = 0, };
256
257 return nd_size_select_show(0,
258 nd_pfn_supported_alignments(aligns), buf);
259 }
260 static DEVICE_ATTR_RO(supported_alignments);
261
262 static struct attribute *nd_pfn_attributes[] = {
263 &dev_attr_mode.attr,
264 &dev_attr_namespace.attr,
265 &dev_attr_uuid.attr,
266 &dev_attr_align.attr,
267 &dev_attr_resource.attr,
268 &dev_attr_size.attr,
269 &dev_attr_supported_alignments.attr,
270 NULL,
271 };
272
273 static struct attribute_group nd_pfn_attribute_group = {
274 .attrs = nd_pfn_attributes,
275 };
276
277 const struct attribute_group *nd_pfn_attribute_groups[] = {
278 &nd_pfn_attribute_group,
279 &nd_device_attribute_group,
280 &nd_numa_attribute_group,
281 NULL,
282 };
283
284 static const struct device_type nd_pfn_device_type = {
285 .name = "nd_pfn",
286 .release = nd_pfn_release,
287 .groups = nd_pfn_attribute_groups,
288 };
289
is_nd_pfn(struct device * dev)290 bool is_nd_pfn(struct device *dev)
291 {
292 return dev ? dev->type == &nd_pfn_device_type : false;
293 }
294 EXPORT_SYMBOL(is_nd_pfn);
295
296 static struct lock_class_key nvdimm_pfn_key;
297
nd_pfn_devinit(struct nd_pfn * nd_pfn,struct nd_namespace_common * ndns)298 struct device *nd_pfn_devinit(struct nd_pfn *nd_pfn,
299 struct nd_namespace_common *ndns)
300 {
301 struct device *dev;
302
303 if (!nd_pfn)
304 return NULL;
305
306 nd_pfn->mode = PFN_MODE_NONE;
307 nd_pfn->align = nd_pfn_default_alignment();
308 dev = &nd_pfn->dev;
309 device_initialize(&nd_pfn->dev);
310 lockdep_set_class(&nd_pfn->dev.mutex, &nvdimm_pfn_key);
311 if (ndns && !__nd_attach_ndns(&nd_pfn->dev, ndns, &nd_pfn->ndns)) {
312 dev_dbg(&ndns->dev, "failed, already claimed by %s\n",
313 dev_name(ndns->claim));
314 put_device(dev);
315 return NULL;
316 }
317 return dev;
318 }
319
nd_pfn_alloc(struct nd_region * nd_region)320 static struct nd_pfn *nd_pfn_alloc(struct nd_region *nd_region)
321 {
322 struct nd_pfn *nd_pfn;
323 struct device *dev;
324
325 nd_pfn = kzalloc(sizeof(*nd_pfn), GFP_KERNEL);
326 if (!nd_pfn)
327 return NULL;
328
329 nd_pfn->id = ida_simple_get(&nd_region->pfn_ida, 0, 0, GFP_KERNEL);
330 if (nd_pfn->id < 0) {
331 kfree(nd_pfn);
332 return NULL;
333 }
334
335 dev = &nd_pfn->dev;
336 dev_set_name(dev, "pfn%d.%d", nd_region->id, nd_pfn->id);
337 dev->type = &nd_pfn_device_type;
338 dev->parent = &nd_region->dev;
339
340 return nd_pfn;
341 }
342
nd_pfn_create(struct nd_region * nd_region)343 struct device *nd_pfn_create(struct nd_region *nd_region)
344 {
345 struct nd_pfn *nd_pfn;
346 struct device *dev;
347
348 if (!is_memory(&nd_region->dev))
349 return NULL;
350
351 nd_pfn = nd_pfn_alloc(nd_region);
352 dev = nd_pfn_devinit(nd_pfn, NULL);
353
354 nd_device_register(dev);
355 return dev;
356 }
357
358 /*
359 * nd_pfn_clear_memmap_errors() clears any errors in the volatile memmap
360 * space associated with the namespace. If the memmap is set to DRAM, then
361 * this is a no-op. Since the memmap area is freshly initialized during
362 * probe, we have an opportunity to clear any badblocks in this area.
363 */
nd_pfn_clear_memmap_errors(struct nd_pfn * nd_pfn)364 static int nd_pfn_clear_memmap_errors(struct nd_pfn *nd_pfn)
365 {
366 struct nd_region *nd_region = to_nd_region(nd_pfn->dev.parent);
367 struct nd_namespace_common *ndns = nd_pfn->ndns;
368 void *zero_page = page_address(ZERO_PAGE(0));
369 struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb;
370 int num_bad, meta_num, rc, bb_present;
371 sector_t first_bad, meta_start;
372 struct nd_namespace_io *nsio;
373
374 if (nd_pfn->mode != PFN_MODE_PMEM)
375 return 0;
376
377 nsio = to_nd_namespace_io(&ndns->dev);
378 meta_start = (SZ_4K + sizeof(*pfn_sb)) >> 9;
379 meta_num = (le64_to_cpu(pfn_sb->dataoff) >> 9) - meta_start;
380
381 /*
382 * re-enable the namespace with correct size so that we can access
383 * the device memmap area.
384 */
385 devm_namespace_disable(&nd_pfn->dev, ndns);
386 rc = devm_namespace_enable(&nd_pfn->dev, ndns, le64_to_cpu(pfn_sb->dataoff));
387 if (rc)
388 return rc;
389
390 do {
391 unsigned long zero_len;
392 u64 nsoff;
393
394 bb_present = badblocks_check(&nd_region->bb, meta_start,
395 meta_num, &first_bad, &num_bad);
396 if (bb_present) {
397 dev_dbg(&nd_pfn->dev, "meta: %x badblocks at %llx\n",
398 num_bad, first_bad);
399 nsoff = ALIGN_DOWN((nd_region->ndr_start
400 + (first_bad << 9)) - nsio->res.start,
401 PAGE_SIZE);
402 zero_len = ALIGN(num_bad << 9, PAGE_SIZE);
403 while (zero_len) {
404 unsigned long chunk = min(zero_len, PAGE_SIZE);
405
406 rc = nvdimm_write_bytes(ndns, nsoff, zero_page,
407 chunk, 0);
408 if (rc)
409 break;
410
411 zero_len -= chunk;
412 nsoff += chunk;
413 }
414 if (rc) {
415 dev_err(&nd_pfn->dev,
416 "error clearing %x badblocks at %llx\n",
417 num_bad, first_bad);
418 return rc;
419 }
420 }
421 } while (bb_present);
422
423 return 0;
424 }
425
nd_supported_alignment(unsigned long align)426 static bool nd_supported_alignment(unsigned long align)
427 {
428 int i;
429 unsigned long supported[MAX_NVDIMM_ALIGN] = { [0] = 0, };
430
431 if (align == 0)
432 return false;
433
434 nd_pfn_supported_alignments(supported);
435 for (i = 0; supported[i]; i++)
436 if (align == supported[i])
437 return true;
438 return false;
439 }
440
441 /**
442 * nd_pfn_validate - read and validate info-block
443 * @nd_pfn: fsdax namespace runtime state / properties
444 * @sig: 'devdax' or 'fsdax' signature
445 *
446 * Upon return the info-block buffer contents (->pfn_sb) are
447 * indeterminate when validation fails, and a coherent info-block
448 * otherwise.
449 */
nd_pfn_validate(struct nd_pfn * nd_pfn,const char * sig)450 int nd_pfn_validate(struct nd_pfn *nd_pfn, const char *sig)
451 {
452 u64 checksum, offset;
453 struct resource *res;
454 enum nd_pfn_mode mode;
455 struct nd_namespace_io *nsio;
456 unsigned long align, start_pad;
457 struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb;
458 struct nd_namespace_common *ndns = nd_pfn->ndns;
459 const uuid_t *parent_uuid = nd_dev_to_uuid(&ndns->dev);
460
461 if (!pfn_sb || !ndns)
462 return -ENODEV;
463
464 if (!is_memory(nd_pfn->dev.parent))
465 return -ENODEV;
466
467 if (nvdimm_read_bytes(ndns, SZ_4K, pfn_sb, sizeof(*pfn_sb), 0))
468 return -ENXIO;
469
470 if (memcmp(pfn_sb->signature, sig, PFN_SIG_LEN) != 0)
471 return -ENODEV;
472
473 checksum = le64_to_cpu(pfn_sb->checksum);
474 pfn_sb->checksum = 0;
475 if (checksum != nd_sb_checksum((struct nd_gen_sb *) pfn_sb))
476 return -ENODEV;
477 pfn_sb->checksum = cpu_to_le64(checksum);
478
479 if (memcmp(pfn_sb->parent_uuid, parent_uuid, 16) != 0)
480 return -ENODEV;
481
482 if (__le16_to_cpu(pfn_sb->version_minor) < 1) {
483 pfn_sb->start_pad = 0;
484 pfn_sb->end_trunc = 0;
485 }
486
487 if (__le16_to_cpu(pfn_sb->version_minor) < 2)
488 pfn_sb->align = 0;
489
490 if (__le16_to_cpu(pfn_sb->version_minor) < 4) {
491 pfn_sb->page_struct_size = cpu_to_le16(64);
492 pfn_sb->page_size = cpu_to_le32(PAGE_SIZE);
493 }
494
495 switch (le32_to_cpu(pfn_sb->mode)) {
496 case PFN_MODE_RAM:
497 case PFN_MODE_PMEM:
498 break;
499 default:
500 return -ENXIO;
501 }
502
503 align = le32_to_cpu(pfn_sb->align);
504 offset = le64_to_cpu(pfn_sb->dataoff);
505 start_pad = le32_to_cpu(pfn_sb->start_pad);
506 if (align == 0)
507 align = 1UL << ilog2(offset);
508 mode = le32_to_cpu(pfn_sb->mode);
509
510 if ((le32_to_cpu(pfn_sb->page_size) > PAGE_SIZE) &&
511 (mode == PFN_MODE_PMEM)) {
512 dev_err(&nd_pfn->dev,
513 "init failed, page size mismatch %d\n",
514 le32_to_cpu(pfn_sb->page_size));
515 return -EOPNOTSUPP;
516 }
517
518 if ((le16_to_cpu(pfn_sb->page_struct_size) < sizeof(struct page)) &&
519 (mode == PFN_MODE_PMEM)) {
520 dev_err(&nd_pfn->dev,
521 "init failed, struct page size mismatch %d\n",
522 le16_to_cpu(pfn_sb->page_struct_size));
523 return -EOPNOTSUPP;
524 }
525
526 /*
527 * Check whether the we support the alignment. For Dax if the
528 * superblock alignment is not matching, we won't initialize
529 * the device.
530 */
531 if (!nd_supported_alignment(align) &&
532 !memcmp(pfn_sb->signature, DAX_SIG, PFN_SIG_LEN)) {
533 dev_err(&nd_pfn->dev, "init failed, alignment mismatch: "
534 "%ld:%ld\n", nd_pfn->align, align);
535 return -EOPNOTSUPP;
536 }
537
538 if (!nd_pfn->uuid) {
539 /*
540 * When probing a namepace via nd_pfn_probe() the uuid
541 * is NULL (see: nd_pfn_devinit()) we init settings from
542 * pfn_sb
543 */
544 nd_pfn->uuid = kmemdup(pfn_sb->uuid, 16, GFP_KERNEL);
545 if (!nd_pfn->uuid)
546 return -ENOMEM;
547 nd_pfn->align = align;
548 nd_pfn->mode = mode;
549 } else {
550 /*
551 * When probing a pfn / dax instance we validate the
552 * live settings against the pfn_sb
553 */
554 if (memcmp(nd_pfn->uuid, pfn_sb->uuid, 16) != 0)
555 return -ENODEV;
556
557 /*
558 * If the uuid validates, but other settings mismatch
559 * return EINVAL because userspace has managed to change
560 * the configuration without specifying new
561 * identification.
562 */
563 if (nd_pfn->align != align || nd_pfn->mode != mode) {
564 dev_err(&nd_pfn->dev,
565 "init failed, settings mismatch\n");
566 dev_dbg(&nd_pfn->dev, "align: %lx:%lx mode: %d:%d\n",
567 nd_pfn->align, align, nd_pfn->mode,
568 mode);
569 return -EOPNOTSUPP;
570 }
571 }
572
573 if (align > nvdimm_namespace_capacity(ndns)) {
574 dev_err(&nd_pfn->dev, "alignment: %lx exceeds capacity %llx\n",
575 align, nvdimm_namespace_capacity(ndns));
576 return -EOPNOTSUPP;
577 }
578
579 /*
580 * These warnings are verbose because they can only trigger in
581 * the case where the physical address alignment of the
582 * namespace has changed since the pfn superblock was
583 * established.
584 */
585 nsio = to_nd_namespace_io(&ndns->dev);
586 res = &nsio->res;
587 if (offset >= resource_size(res)) {
588 dev_err(&nd_pfn->dev, "pfn array size exceeds capacity of %s\n",
589 dev_name(&ndns->dev));
590 return -EOPNOTSUPP;
591 }
592
593 if ((align && !IS_ALIGNED(res->start + offset + start_pad, align))
594 || !IS_ALIGNED(offset, PAGE_SIZE)) {
595 dev_err(&nd_pfn->dev,
596 "bad offset: %#llx dax disabled align: %#lx\n",
597 offset, align);
598 return -EOPNOTSUPP;
599 }
600
601 if (!IS_ALIGNED(res->start + le32_to_cpu(pfn_sb->start_pad),
602 memremap_compat_align())) {
603 dev_err(&nd_pfn->dev, "resource start misaligned\n");
604 return -EOPNOTSUPP;
605 }
606
607 if (!IS_ALIGNED(res->end + 1 - le32_to_cpu(pfn_sb->end_trunc),
608 memremap_compat_align())) {
609 dev_err(&nd_pfn->dev, "resource end misaligned\n");
610 return -EOPNOTSUPP;
611 }
612
613 return 0;
614 }
615 EXPORT_SYMBOL(nd_pfn_validate);
616
nd_pfn_probe(struct device * dev,struct nd_namespace_common * ndns)617 int nd_pfn_probe(struct device *dev, struct nd_namespace_common *ndns)
618 {
619 int rc;
620 struct nd_pfn *nd_pfn;
621 struct device *pfn_dev;
622 struct nd_pfn_sb *pfn_sb;
623 struct nd_region *nd_region = to_nd_region(ndns->dev.parent);
624
625 if (ndns->force_raw)
626 return -ENODEV;
627
628 switch (ndns->claim_class) {
629 case NVDIMM_CCLASS_NONE:
630 case NVDIMM_CCLASS_PFN:
631 break;
632 default:
633 return -ENODEV;
634 }
635
636 nvdimm_bus_lock(&ndns->dev);
637 nd_pfn = nd_pfn_alloc(nd_region);
638 pfn_dev = nd_pfn_devinit(nd_pfn, ndns);
639 nvdimm_bus_unlock(&ndns->dev);
640 if (!pfn_dev)
641 return -ENOMEM;
642 pfn_sb = devm_kmalloc(dev, sizeof(*pfn_sb), GFP_KERNEL);
643 nd_pfn = to_nd_pfn(pfn_dev);
644 nd_pfn->pfn_sb = pfn_sb;
645 rc = nd_pfn_validate(nd_pfn, PFN_SIG);
646 dev_dbg(dev, "pfn: %s\n", rc == 0 ? dev_name(pfn_dev) : "<none>");
647 if (rc < 0) {
648 nd_detach_ndns(pfn_dev, &nd_pfn->ndns);
649 put_device(pfn_dev);
650 } else
651 nd_device_register(pfn_dev);
652
653 return rc;
654 }
655 EXPORT_SYMBOL(nd_pfn_probe);
656
657 /*
658 * We hotplug memory at sub-section granularity, pad the reserved area
659 * from the previous section base to the namespace base address.
660 */
init_altmap_base(resource_size_t base)661 static unsigned long init_altmap_base(resource_size_t base)
662 {
663 unsigned long base_pfn = PHYS_PFN(base);
664
665 return SUBSECTION_ALIGN_DOWN(base_pfn);
666 }
667
init_altmap_reserve(resource_size_t base)668 static unsigned long init_altmap_reserve(resource_size_t base)
669 {
670 unsigned long reserve = nd_info_block_reserve() >> PAGE_SHIFT;
671 unsigned long base_pfn = PHYS_PFN(base);
672
673 reserve += base_pfn - SUBSECTION_ALIGN_DOWN(base_pfn);
674 return reserve;
675 }
676
__nvdimm_setup_pfn(struct nd_pfn * nd_pfn,struct dev_pagemap * pgmap)677 static int __nvdimm_setup_pfn(struct nd_pfn *nd_pfn, struct dev_pagemap *pgmap)
678 {
679 struct range *range = &pgmap->range;
680 struct vmem_altmap *altmap = &pgmap->altmap;
681 struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb;
682 u64 offset = le64_to_cpu(pfn_sb->dataoff);
683 u32 start_pad = __le32_to_cpu(pfn_sb->start_pad);
684 u32 end_trunc = __le32_to_cpu(pfn_sb->end_trunc);
685 u32 reserve = nd_info_block_reserve();
686 struct nd_namespace_common *ndns = nd_pfn->ndns;
687 struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
688 resource_size_t base = nsio->res.start + start_pad;
689 resource_size_t end = nsio->res.end - end_trunc;
690 struct vmem_altmap __altmap = {
691 .base_pfn = init_altmap_base(base),
692 .reserve = init_altmap_reserve(base),
693 .end_pfn = PHYS_PFN(end),
694 };
695
696 *range = (struct range) {
697 .start = nsio->res.start + start_pad,
698 .end = nsio->res.end - end_trunc,
699 };
700 pgmap->nr_range = 1;
701 if (nd_pfn->mode == PFN_MODE_RAM) {
702 if (offset < reserve)
703 return -EINVAL;
704 nd_pfn->npfns = le64_to_cpu(pfn_sb->npfns);
705 } else if (nd_pfn->mode == PFN_MODE_PMEM) {
706 nd_pfn->npfns = PHYS_PFN((range_len(range) - offset));
707 if (le64_to_cpu(nd_pfn->pfn_sb->npfns) > nd_pfn->npfns)
708 dev_info(&nd_pfn->dev,
709 "number of pfns truncated from %lld to %ld\n",
710 le64_to_cpu(nd_pfn->pfn_sb->npfns),
711 nd_pfn->npfns);
712 memcpy(altmap, &__altmap, sizeof(*altmap));
713 altmap->free = PHYS_PFN(offset - reserve);
714 altmap->alloc = 0;
715 pgmap->flags |= PGMAP_ALTMAP_VALID;
716 } else
717 return -ENXIO;
718
719 return 0;
720 }
721
nd_pfn_init(struct nd_pfn * nd_pfn)722 static int nd_pfn_init(struct nd_pfn *nd_pfn)
723 {
724 struct nd_namespace_common *ndns = nd_pfn->ndns;
725 struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
726 resource_size_t start, size;
727 struct nd_region *nd_region;
728 unsigned long npfns, align;
729 u32 end_trunc;
730 struct nd_pfn_sb *pfn_sb;
731 phys_addr_t offset;
732 const char *sig;
733 u64 checksum;
734 int rc;
735
736 pfn_sb = devm_kmalloc(&nd_pfn->dev, sizeof(*pfn_sb), GFP_KERNEL);
737 if (!pfn_sb)
738 return -ENOMEM;
739
740 nd_pfn->pfn_sb = pfn_sb;
741 if (is_nd_dax(&nd_pfn->dev))
742 sig = DAX_SIG;
743 else
744 sig = PFN_SIG;
745
746 rc = nd_pfn_validate(nd_pfn, sig);
747 if (rc == 0)
748 return nd_pfn_clear_memmap_errors(nd_pfn);
749 if (rc != -ENODEV)
750 return rc;
751
752 /* no info block, do init */;
753 memset(pfn_sb, 0, sizeof(*pfn_sb));
754
755 nd_region = to_nd_region(nd_pfn->dev.parent);
756 if (nd_region->ro) {
757 dev_info(&nd_pfn->dev,
758 "%s is read-only, unable to init metadata\n",
759 dev_name(&nd_region->dev));
760 return -ENXIO;
761 }
762
763 start = nsio->res.start;
764 size = resource_size(&nsio->res);
765 npfns = PHYS_PFN(size - SZ_8K);
766 align = max(nd_pfn->align, memremap_compat_align());
767
768 /*
769 * When @start is misaligned fail namespace creation. See
770 * the 'struct nd_pfn_sb' commentary on why ->start_pad is not
771 * an option.
772 */
773 if (!IS_ALIGNED(start, memremap_compat_align())) {
774 dev_err(&nd_pfn->dev, "%s: start %pa misaligned to %#lx\n",
775 dev_name(&ndns->dev), &start,
776 memremap_compat_align());
777 return -EINVAL;
778 }
779 end_trunc = start + size - ALIGN_DOWN(start + size, align);
780 if (nd_pfn->mode == PFN_MODE_PMEM) {
781 unsigned long page_map_size = MAX_STRUCT_PAGE_SIZE * npfns;
782
783 /*
784 * The altmap should be padded out to the block size used
785 * when populating the vmemmap. This *should* be equal to
786 * PMD_SIZE for most architectures.
787 *
788 * Also make sure size of struct page is less than
789 * MAX_STRUCT_PAGE_SIZE. The goal here is compatibility in the
790 * face of production kernel configurations that reduce the
791 * 'struct page' size below MAX_STRUCT_PAGE_SIZE. For debug
792 * kernel configurations that increase the 'struct page' size
793 * above MAX_STRUCT_PAGE_SIZE, the page_struct_override allows
794 * for continuing with the capacity that will be wasted when
795 * reverting to a production kernel configuration. Otherwise,
796 * those configurations are blocked by default.
797 */
798 if (sizeof(struct page) > MAX_STRUCT_PAGE_SIZE) {
799 if (page_struct_override)
800 page_map_size = sizeof(struct page) * npfns;
801 else {
802 dev_err(&nd_pfn->dev,
803 "Memory debug options prevent using pmem for the page map\n");
804 return -EINVAL;
805 }
806 }
807 offset = ALIGN(start + SZ_8K + page_map_size, align) - start;
808 } else if (nd_pfn->mode == PFN_MODE_RAM)
809 offset = ALIGN(start + SZ_8K, align) - start;
810 else
811 return -ENXIO;
812
813 if (offset >= size) {
814 dev_err(&nd_pfn->dev, "%s unable to satisfy requested alignment\n",
815 dev_name(&ndns->dev));
816 return -ENXIO;
817 }
818
819 npfns = PHYS_PFN(size - offset - end_trunc);
820 pfn_sb->mode = cpu_to_le32(nd_pfn->mode);
821 pfn_sb->dataoff = cpu_to_le64(offset);
822 pfn_sb->npfns = cpu_to_le64(npfns);
823 memcpy(pfn_sb->signature, sig, PFN_SIG_LEN);
824 memcpy(pfn_sb->uuid, nd_pfn->uuid, 16);
825 memcpy(pfn_sb->parent_uuid, nd_dev_to_uuid(&ndns->dev), 16);
826 pfn_sb->version_major = cpu_to_le16(1);
827 pfn_sb->version_minor = cpu_to_le16(4);
828 pfn_sb->end_trunc = cpu_to_le32(end_trunc);
829 pfn_sb->align = cpu_to_le32(nd_pfn->align);
830 if (sizeof(struct page) > MAX_STRUCT_PAGE_SIZE && page_struct_override)
831 pfn_sb->page_struct_size = cpu_to_le16(sizeof(struct page));
832 else
833 pfn_sb->page_struct_size = cpu_to_le16(MAX_STRUCT_PAGE_SIZE);
834 pfn_sb->page_size = cpu_to_le32(PAGE_SIZE);
835 checksum = nd_sb_checksum((struct nd_gen_sb *) pfn_sb);
836 pfn_sb->checksum = cpu_to_le64(checksum);
837
838 rc = nd_pfn_clear_memmap_errors(nd_pfn);
839 if (rc)
840 return rc;
841
842 return nvdimm_write_bytes(ndns, SZ_4K, pfn_sb, sizeof(*pfn_sb), 0);
843 }
844
845 /*
846 * Determine the effective resource range and vmem_altmap from an nd_pfn
847 * instance.
848 */
nvdimm_setup_pfn(struct nd_pfn * nd_pfn,struct dev_pagemap * pgmap)849 int nvdimm_setup_pfn(struct nd_pfn *nd_pfn, struct dev_pagemap *pgmap)
850 {
851 int rc;
852
853 if (!nd_pfn->uuid || !nd_pfn->ndns)
854 return -ENODEV;
855
856 rc = nd_pfn_init(nd_pfn);
857 if (rc)
858 return rc;
859
860 /* we need a valid pfn_sb before we can init a dev_pagemap */
861 return __nvdimm_setup_pfn(nd_pfn, pgmap);
862 }
863 EXPORT_SYMBOL_GPL(nvdimm_setup_pfn);
864