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