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