1/*
2 * Copyright(c) 2013-2016 Intel Corporation. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of version 2 of the GNU General Public License as
6 * published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 */
13#include <linux/memremap.h>
14#include <linux/blkdev.h>
15#include <linux/device.h>
16#include <linux/genhd.h>
17#include <linux/sizes.h>
18#include <linux/slab.h>
19#include <linux/fs.h>
20#include <linux/mm.h>
21#include "nd-core.h"
22#include "pfn.h"
23#include "nd.h"
24
25static void nd_pfn_release(struct device *dev)
26{
27 struct nd_region *nd_region = to_nd_region(dev->parent);
28 struct nd_pfn *nd_pfn = to_nd_pfn(dev);
29
30 dev_dbg(dev, "trace\n");
31 nd_detach_ndns(&nd_pfn->dev, &nd_pfn->ndns);
32 ida_simple_remove(&nd_region->pfn_ida, nd_pfn->id);
33 kfree(nd_pfn->uuid);
34 kfree(nd_pfn);
35}
36
37static struct device_type nd_pfn_device_type = {
38 .name = "nd_pfn",
39 .release = nd_pfn_release,
40};
41
42bool is_nd_pfn(struct device *dev)
43{
44 return dev ? dev->type == &nd_pfn_device_type : false;
45}
46EXPORT_SYMBOL(is_nd_pfn);
47
48struct nd_pfn *to_nd_pfn(struct device *dev)
49{
50 struct nd_pfn *nd_pfn = container_of(dev, struct nd_pfn, dev);
51
52 WARN_ON(!is_nd_pfn(dev));
53 return nd_pfn;
54}
55EXPORT_SYMBOL(to_nd_pfn);
56
57static ssize_t mode_show(struct device *dev,
58 struct device_attribute *attr, char *buf)
59{
60 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
61
62 switch (nd_pfn->mode) {
63 case PFN_MODE_RAM:
64 return sprintf(buf, "ram\n");
65 case PFN_MODE_PMEM:
66 return sprintf(buf, "pmem\n");
67 default:
68 return sprintf(buf, "none\n");
69 }
70}
71
72static ssize_t mode_store(struct device *dev,
73 struct device_attribute *attr, const char *buf, size_t len)
74{
75 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
76 ssize_t rc = 0;
77
78 device_lock(dev);
79 nvdimm_bus_lock(dev);
80 if (dev->driver)
81 rc = -EBUSY;
82 else {
83 size_t n = len - 1;
84
85 if (strncmp(buf, "pmem\n", n) == 0
86 || strncmp(buf, "pmem", n) == 0) {
87 nd_pfn->mode = PFN_MODE_PMEM;
88 } else if (strncmp(buf, "ram\n", n) == 0
89 || strncmp(buf, "ram", n) == 0)
90 nd_pfn->mode = PFN_MODE_RAM;
91 else if (strncmp(buf, "none\n", n) == 0
92 || strncmp(buf, "none", n) == 0)
93 nd_pfn->mode = PFN_MODE_NONE;
94 else
95 rc = -EINVAL;
96 }
97 dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
98 buf[len - 1] == '\n' ? "" : "\n");
99 nvdimm_bus_unlock(dev);
100 device_unlock(dev);
101
102 return rc ? rc : len;
103}
104static DEVICE_ATTR_RW(mode);
105
106static ssize_t align_show(struct device *dev,
107 struct device_attribute *attr, char *buf)
108{
109 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
110
111 return sprintf(buf, "%ld\n", nd_pfn->align);
112}
113
114static const unsigned long *nd_pfn_supported_alignments(void)
115{
116 /*
117 * This needs to be a non-static variable because the *_SIZE
118 * macros aren't always constants.
119 */
120 const unsigned long supported_alignments[] = {
121 PAGE_SIZE,
122#ifdef CONFIG_TRANSPARENT_HUGEPAGE
123 HPAGE_PMD_SIZE,
124#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
125 HPAGE_PUD_SIZE,
126#endif
127#endif
128 0,
129 };
130 static unsigned long data[ARRAY_SIZE(supported_alignments)];
131
132 memcpy(data, supported_alignments, sizeof(data));
133
134 return data;
135}
136
137static ssize_t align_store(struct device *dev,
138 struct device_attribute *attr, const char *buf, size_t len)
139{
140 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
141 ssize_t rc;
142
143 device_lock(dev);
144 nvdimm_bus_lock(dev);
145 rc = nd_size_select_store(dev, buf, &nd_pfn->align,
146 nd_pfn_supported_alignments());
147 dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
148 buf[len - 1] == '\n' ? "" : "\n");
149 nvdimm_bus_unlock(dev);
150 device_unlock(dev);
151
152 return rc ? rc : len;
153}
154static DEVICE_ATTR_RW(align);
155
156static ssize_t uuid_show(struct device *dev,
157 struct device_attribute *attr, char *buf)
158{
159 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
160
161 if (nd_pfn->uuid)
162 return sprintf(buf, "%pUb\n", nd_pfn->uuid);
163 return sprintf(buf, "\n");
164}
165
166static ssize_t uuid_store(struct device *dev,
167 struct device_attribute *attr, const char *buf, size_t len)
168{
169 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
170 ssize_t rc;
171
172 device_lock(dev);
173 rc = nd_uuid_store(dev, &nd_pfn->uuid, buf, len);
174 dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
175 buf[len - 1] == '\n' ? "" : "\n");
176 device_unlock(dev);
177
178 return rc ? rc : len;
179}
180static DEVICE_ATTR_RW(uuid);
181
182static ssize_t namespace_show(struct device *dev,
183 struct device_attribute *attr, char *buf)
184{
185 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
186 ssize_t rc;
187
188 nvdimm_bus_lock(dev);
189 rc = sprintf(buf, "%s\n", nd_pfn->ndns
190 ? dev_name(&nd_pfn->ndns->dev) : "");
191 nvdimm_bus_unlock(dev);
192 return rc;
193}
194
195static ssize_t namespace_store(struct device *dev,
196 struct device_attribute *attr, const char *buf, size_t len)
197{
198 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
199 ssize_t rc;
200
201 device_lock(dev);
202 nvdimm_bus_lock(dev);
203 rc = nd_namespace_store(dev, &nd_pfn->ndns, buf, len);
204 dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
205 buf[len - 1] == '\n' ? "" : "\n");
206 nvdimm_bus_unlock(dev);
207 device_unlock(dev);
208
209 return rc;
210}
211static DEVICE_ATTR_RW(namespace);
212
213static ssize_t resource_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 struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
226
227 rc = sprintf(buf, "%#llx\n", (unsigned long long) nsio->res.start
228 + start_pad + offset);
229 } else {
230 /* no address to convey if the pfn instance is disabled */
231 rc = -ENXIO;
232 }
233 device_unlock(dev);
234
235 return rc;
236}
237static DEVICE_ATTR_RO(resource);
238
239static ssize_t size_show(struct device *dev,
240 struct device_attribute *attr, char *buf)
241{
242 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
243 ssize_t rc;
244
245 device_lock(dev);
246 if (dev->driver) {
247 struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb;
248 u64 offset = __le64_to_cpu(pfn_sb->dataoff);
249 struct nd_namespace_common *ndns = nd_pfn->ndns;
250 u32 start_pad = __le32_to_cpu(pfn_sb->start_pad);
251 u32 end_trunc = __le32_to_cpu(pfn_sb->end_trunc);
252 struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
253
254 rc = sprintf(buf, "%llu\n", (unsigned long long)
255 resource_size(&nsio->res) - start_pad
256 - end_trunc - offset);
257 } else {
258 /* no size to convey if the pfn instance is disabled */
259 rc = -ENXIO;
260 }
261 device_unlock(dev);
262
263 return rc;
264}
265static DEVICE_ATTR_RO(size);
266
267static ssize_t supported_alignments_show(struct device *dev,
268 struct device_attribute *attr, char *buf)
269{
270 return nd_size_select_show(0, nd_pfn_supported_alignments(), buf);
271}
272static DEVICE_ATTR_RO(supported_alignments);
273
274static struct attribute *nd_pfn_attributes[] = {
275 &dev_attr_mode.attr,
276 &dev_attr_namespace.attr,
277 &dev_attr_uuid.attr,
278 &dev_attr_align.attr,
279 &dev_attr_resource.attr,
280 &dev_attr_size.attr,
281 &dev_attr_supported_alignments.attr,
282 NULL,
283};
284
285static umode_t pfn_visible(struct kobject *kobj, struct attribute *a, int n)
286{
287 if (a == &dev_attr_resource.attr)
288 return 0400;
289 return a->mode;
290}
291
292struct attribute_group nd_pfn_attribute_group = {
293 .attrs = nd_pfn_attributes,
294 .is_visible = pfn_visible,
295};
296
297static const struct attribute_group *nd_pfn_attribute_groups[] = {
298 &nd_pfn_attribute_group,
299 &nd_device_attribute_group,
300 &nd_numa_attribute_group,
301 NULL,
302};
303
304struct device *nd_pfn_devinit(struct nd_pfn *nd_pfn,
305 struct nd_namespace_common *ndns)
306{
307 struct device *dev;
308
309 if (!nd_pfn)
310 return NULL;
311
312 nd_pfn->mode = PFN_MODE_NONE;
313 nd_pfn->align = PFN_DEFAULT_ALIGNMENT;
314 dev = &nd_pfn->dev;
315 device_initialize(&nd_pfn->dev);
316 if (ndns && !__nd_attach_ndns(&nd_pfn->dev, ndns, &nd_pfn->ndns)) {
317 dev_dbg(&ndns->dev, "failed, already claimed by %s\n",
318 dev_name(ndns->claim));
319 put_device(dev);
320 return NULL;
321 }
322 return dev;
323}
324
325static struct nd_pfn *nd_pfn_alloc(struct nd_region *nd_region)
326{
327 struct nd_pfn *nd_pfn;
328 struct device *dev;
329
330 nd_pfn = kzalloc(sizeof(*nd_pfn), GFP_KERNEL);
331 if (!nd_pfn)
332 return NULL;
333
334 nd_pfn->id = ida_simple_get(&nd_region->pfn_ida, 0, 0, GFP_KERNEL);
335 if (nd_pfn->id < 0) {
336 kfree(nd_pfn);
337 return NULL;
338 }
339
340 dev = &nd_pfn->dev;
341 dev_set_name(dev, "pfn%d.%d", nd_region->id, nd_pfn->id);
342 dev->groups = nd_pfn_attribute_groups;
343 dev->type = &nd_pfn_device_type;
344 dev->parent = &nd_region->dev;
345
346 return nd_pfn;
347}
348
349struct device *nd_pfn_create(struct nd_region *nd_region)
350{
351 struct nd_pfn *nd_pfn;
352 struct device *dev;
353
354 if (!is_memory(&nd_region->dev))
355 return NULL;
356
357 nd_pfn = nd_pfn_alloc(nd_region);
358 dev = nd_pfn_devinit(nd_pfn, NULL);
359
360 __nd_device_register(dev);
361 return dev;
362}
363
364/*
365 * nd_pfn_clear_memmap_errors() clears any errors in the volatile memmap
366 * space associated with the namespace. If the memmap is set to DRAM, then
367 * this is a no-op. Since the memmap area is freshly initialized during
368 * probe, we have an opportunity to clear any badblocks in this area.
369 */
370static int nd_pfn_clear_memmap_errors(struct nd_pfn *nd_pfn)
371{
372 struct nd_region *nd_region = to_nd_region(nd_pfn->dev.parent);
373 struct nd_namespace_common *ndns = nd_pfn->ndns;
374 void *zero_page = page_address(ZERO_PAGE(0));
375 struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb;
376 int num_bad, meta_num, rc, bb_present;
377 sector_t first_bad, meta_start;
378 struct nd_namespace_io *nsio;
379
380 if (nd_pfn->mode != PFN_MODE_PMEM)
381 return 0;
382
383 nsio = to_nd_namespace_io(&ndns->dev);
384 meta_start = (SZ_4K + sizeof(*pfn_sb)) >> 9;
385 meta_num = (le64_to_cpu(pfn_sb->dataoff) >> 9) - meta_start;
386
387 do {
388 unsigned long zero_len;
389 u64 nsoff;
390
391 bb_present = badblocks_check(&nd_region->bb, meta_start,
392 meta_num, &first_bad, &num_bad);
393 if (bb_present) {
394 dev_dbg(&nd_pfn->dev, "meta: %x badblocks at %lx\n",
395 num_bad, first_bad);
396 nsoff = ALIGN_DOWN((nd_region->ndr_start
397 + (first_bad << 9)) - nsio->res.start,
398 PAGE_SIZE);
399 zero_len = ALIGN(num_bad << 9, PAGE_SIZE);
400 while (zero_len) {
401 unsigned long chunk = min(zero_len, PAGE_SIZE);
402
403 rc = nvdimm_write_bytes(ndns, nsoff, zero_page,
404 chunk, 0);
405 if (rc)
406 break;
407
408 zero_len -= chunk;
409 nsoff += chunk;
410 }
411 if (rc) {
412 dev_err(&nd_pfn->dev,
413 "error clearing %x badblocks at %lx\n",
414 num_bad, first_bad);
415 return rc;
416 }
417 }
418 } while (bb_present);
419
420 return 0;
421}
422
423int nd_pfn_validate(struct nd_pfn *nd_pfn, const char *sig)
424{
425 u64 checksum, offset;
426 enum nd_pfn_mode mode;
427 struct nd_namespace_io *nsio;
428 unsigned long align, start_pad;
429 struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb;
430 struct nd_namespace_common *ndns = nd_pfn->ndns;
431 const u8 *parent_uuid = nd_dev_to_uuid(&ndns->dev);
432
433 if (!pfn_sb || !ndns)
434 return -ENODEV;
435
436 if (!is_memory(nd_pfn->dev.parent))
437 return -ENODEV;
438
439 if (nvdimm_read_bytes(ndns, SZ_4K, pfn_sb, sizeof(*pfn_sb), 0))
440 return -ENXIO;
441
442 if (memcmp(pfn_sb->signature, sig, PFN_SIG_LEN) != 0)
443 return -ENODEV;
444
445 checksum = le64_to_cpu(pfn_sb->checksum);
446 pfn_sb->checksum = 0;
447 if (checksum != nd_sb_checksum((struct nd_gen_sb *) pfn_sb))
448 return -ENODEV;
449 pfn_sb->checksum = cpu_to_le64(checksum);
450
451 if (memcmp(pfn_sb->parent_uuid, parent_uuid, 16) != 0)
452 return -ENODEV;
453
454 if (__le16_to_cpu(pfn_sb->version_minor) < 1) {
455 pfn_sb->start_pad = 0;
456 pfn_sb->end_trunc = 0;
457 }
458
459 if (__le16_to_cpu(pfn_sb->version_minor) < 2)
460 pfn_sb->align = 0;
461
462 switch (le32_to_cpu(pfn_sb->mode)) {
463 case PFN_MODE_RAM:
464 case PFN_MODE_PMEM:
465 break;
466 default:
467 return -ENXIO;
468 }
469
470 align = le32_to_cpu(pfn_sb->align);
471 offset = le64_to_cpu(pfn_sb->dataoff);
472 start_pad = le32_to_cpu(pfn_sb->start_pad);
473 if (align == 0)
474 align = 1UL << ilog2(offset);
475 mode = le32_to_cpu(pfn_sb->mode);
476
477 if (!nd_pfn->uuid) {
478 /*
479 * When probing a namepace via nd_pfn_probe() the uuid
480 * is NULL (see: nd_pfn_devinit()) we init settings from
481 * pfn_sb
482 */
483 nd_pfn->uuid = kmemdup(pfn_sb->uuid, 16, GFP_KERNEL);
484 if (!nd_pfn->uuid)
485 return -ENOMEM;
486 nd_pfn->align = align;
487 nd_pfn->mode = mode;
488 } else {
489 /*
490 * When probing a pfn / dax instance we validate the
491 * live settings against the pfn_sb
492 */
493 if (memcmp(nd_pfn->uuid, pfn_sb->uuid, 16) != 0)
494 return -ENODEV;
495
496 /*
497 * If the uuid validates, but other settings mismatch
498 * return EINVAL because userspace has managed to change
499 * the configuration without specifying new
500 * identification.
501 */
502 if (nd_pfn->align != align || nd_pfn->mode != mode) {
503 dev_err(&nd_pfn->dev,
504 "init failed, settings mismatch\n");
505 dev_dbg(&nd_pfn->dev, "align: %lx:%lx mode: %d:%d\n",
506 nd_pfn->align, align, nd_pfn->mode,
507 mode);
508 return -EINVAL;
509 }
510 }
511
512 if (align > nvdimm_namespace_capacity(ndns)) {
513 dev_err(&nd_pfn->dev, "alignment: %lx exceeds capacity %llx\n",
514 align, nvdimm_namespace_capacity(ndns));
515 return -EINVAL;
516 }
517
518 /*
519 * These warnings are verbose because they can only trigger in
520 * the case where the physical address alignment of the
521 * namespace has changed since the pfn superblock was
522 * established.
523 */
524 nsio = to_nd_namespace_io(&ndns->dev);
525 if (offset >= resource_size(&nsio->res)) {
526 dev_err(&nd_pfn->dev, "pfn array size exceeds capacity of %s\n",
527 dev_name(&ndns->dev));
528 return -EBUSY;
529 }
530
531 if ((align && !IS_ALIGNED(nsio->res.start + offset + start_pad, align))
532 || !IS_ALIGNED(offset, PAGE_SIZE)) {
533 dev_err(&nd_pfn->dev,
534 "bad offset: %#llx dax disabled align: %#lx\n",
535 offset, align);
536 return -ENXIO;
537 }
538
539 return nd_pfn_clear_memmap_errors(nd_pfn);
540}
541EXPORT_SYMBOL(nd_pfn_validate);
542
543int nd_pfn_probe(struct device *dev, struct nd_namespace_common *ndns)
544{
545 int rc;
546 struct nd_pfn *nd_pfn;
547 struct device *pfn_dev;
548 struct nd_pfn_sb *pfn_sb;
549 struct nd_region *nd_region = to_nd_region(ndns->dev.parent);
550
551 if (ndns->force_raw)
552 return -ENODEV;
553
554 switch (ndns->claim_class) {
555 case NVDIMM_CCLASS_NONE:
556 case NVDIMM_CCLASS_PFN:
557 break;
558 default:
559 return -ENODEV;
560 }
561
562 nvdimm_bus_lock(&ndns->dev);
563 nd_pfn = nd_pfn_alloc(nd_region);
564 pfn_dev = nd_pfn_devinit(nd_pfn, ndns);
565 nvdimm_bus_unlock(&ndns->dev);
566 if (!pfn_dev)
567 return -ENOMEM;
568 pfn_sb = devm_kzalloc(dev, sizeof(*pfn_sb), GFP_KERNEL);
569 nd_pfn = to_nd_pfn(pfn_dev);
570 nd_pfn->pfn_sb = pfn_sb;
571 rc = nd_pfn_validate(nd_pfn, PFN_SIG);
572 dev_dbg(dev, "pfn: %s\n", rc == 0 ? dev_name(pfn_dev) : "<none>");
573 if (rc < 0) {
574 nd_detach_ndns(pfn_dev, &nd_pfn->ndns);
575 put_device(pfn_dev);
576 } else
577 __nd_device_register(pfn_dev);
578
579 return rc;
580}
581EXPORT_SYMBOL(nd_pfn_probe);
582
583static u32 info_block_reserve(void)
584{
585 return ALIGN(SZ_8K, PAGE_SIZE);
586}
587
588/*
589 * We hotplug memory at section granularity, pad the reserved area from
590 * the previous section base to the namespace base address.
591 */
592static unsigned long init_altmap_base(resource_size_t base)
593{
594 unsigned long base_pfn = PHYS_PFN(base);
595
596 return PFN_SECTION_ALIGN_DOWN(base_pfn);
597}
598
599static unsigned long init_altmap_reserve(resource_size_t base)
600{
601 unsigned long reserve = info_block_reserve() >> PAGE_SHIFT;
602 unsigned long base_pfn = PHYS_PFN(base);
603
604 reserve += base_pfn - PFN_SECTION_ALIGN_DOWN(base_pfn);
605 return reserve;
606}
607
608static int __nvdimm_setup_pfn(struct nd_pfn *nd_pfn, struct dev_pagemap *pgmap)
609{
610 struct resource *res = &pgmap->res;
611 struct vmem_altmap *altmap = &pgmap->altmap;
612 struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb;
613 u64 offset = le64_to_cpu(pfn_sb->dataoff);
614 u32 start_pad = __le32_to_cpu(pfn_sb->start_pad);
615 u32 end_trunc = __le32_to_cpu(pfn_sb->end_trunc);
616 u32 reserve = info_block_reserve();
617 struct nd_namespace_common *ndns = nd_pfn->ndns;
618 struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
619 resource_size_t base = nsio->res.start + start_pad;
620 struct vmem_altmap __altmap = {
621 .base_pfn = init_altmap_base(base),
622 .reserve = init_altmap_reserve(base),
623 };
624
625 memcpy(res, &nsio->res, sizeof(*res));
626 res->start += start_pad;
627 res->end -= end_trunc;
628
629 if (nd_pfn->mode == PFN_MODE_RAM) {
630 if (offset < reserve)
631 return -EINVAL;
632 nd_pfn->npfns = le64_to_cpu(pfn_sb->npfns);
633 pgmap->altmap_valid = false;
634 } else if (nd_pfn->mode == PFN_MODE_PMEM) {
635 nd_pfn->npfns = PFN_SECTION_ALIGN_UP((resource_size(res)
636 - offset) / PAGE_SIZE);
637 if (le64_to_cpu(nd_pfn->pfn_sb->npfns) > nd_pfn->npfns)
638 dev_info(&nd_pfn->dev,
639 "number of pfns truncated from %lld to %ld\n",
640 le64_to_cpu(nd_pfn->pfn_sb->npfns),
641 nd_pfn->npfns);
642 memcpy(altmap, &__altmap, sizeof(*altmap));
643 altmap->free = PHYS_PFN(offset - reserve);
644 altmap->alloc = 0;
645 pgmap->altmap_valid = true;
646 } else
647 return -ENXIO;
648
649 return 0;
650}
651
652static u64 phys_pmem_align_down(struct nd_pfn *nd_pfn, u64 phys)
653{
654 return min_t(u64, PHYS_SECTION_ALIGN_DOWN(phys),
655 ALIGN_DOWN(phys, nd_pfn->align));
656}
657
658/*
659 * Check if pmem collides with 'System RAM', or other regions when
660 * section aligned. Trim it accordingly.
661 */
662static void trim_pfn_device(struct nd_pfn *nd_pfn, u32 *start_pad, u32 *end_trunc)
663{
664 struct nd_namespace_common *ndns = nd_pfn->ndns;
665 struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
666 struct nd_region *nd_region = to_nd_region(nd_pfn->dev.parent);
667 const resource_size_t start = nsio->res.start;
668 const resource_size_t end = start + resource_size(&nsio->res);
669 resource_size_t adjust, size;
670
671 *start_pad = 0;
672 *end_trunc = 0;
673
674 adjust = start - PHYS_SECTION_ALIGN_DOWN(start);
675 size = resource_size(&nsio->res) + adjust;
676 if (region_intersects(start - adjust, size, IORESOURCE_SYSTEM_RAM,
677 IORES_DESC_NONE) == REGION_MIXED
678 || nd_region_conflict(nd_region, start - adjust, size))
679 *start_pad = PHYS_SECTION_ALIGN_UP(start) - start;
680
681 /* Now check that end of the range does not collide. */
682 adjust = PHYS_SECTION_ALIGN_UP(end) - end;
683 size = resource_size(&nsio->res) + adjust;
684 if (region_intersects(start, size, IORESOURCE_SYSTEM_RAM,
685 IORES_DESC_NONE) == REGION_MIXED
686 || !IS_ALIGNED(end, nd_pfn->align)
687 || nd_region_conflict(nd_region, start, size))
688 *end_trunc = end - phys_pmem_align_down(nd_pfn, end);
689}
690
691static int nd_pfn_init(struct nd_pfn *nd_pfn)
692{
693 struct nd_namespace_common *ndns = nd_pfn->ndns;
694 struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
695 u32 start_pad, end_trunc, reserve = info_block_reserve();
696 resource_size_t start, size;
697 struct nd_region *nd_region;
698 struct nd_pfn_sb *pfn_sb;
699 unsigned long npfns;
700 phys_addr_t offset;
701 const char *sig;
702 u64 checksum;
703 int rc;
704
705 pfn_sb = devm_kzalloc(&nd_pfn->dev, sizeof(*pfn_sb), GFP_KERNEL);
706 if (!pfn_sb)
707 return -ENOMEM;
708
709 nd_pfn->pfn_sb = pfn_sb;
710 if (is_nd_dax(&nd_pfn->dev))
711 sig = DAX_SIG;
712 else
713 sig = PFN_SIG;
714 rc = nd_pfn_validate(nd_pfn, sig);
715 if (rc != -ENODEV)
716 return rc;
717
718 /* no info block, do init */;
719 nd_region = to_nd_region(nd_pfn->dev.parent);
720 if (nd_region->ro) {
721 dev_info(&nd_pfn->dev,
722 "%s is read-only, unable to init metadata\n",
723 dev_name(&nd_region->dev));
724 return -ENXIO;
725 }
726
727 memset(pfn_sb, 0, sizeof(*pfn_sb));
728
729 trim_pfn_device(nd_pfn, &start_pad, &end_trunc);
730 if (start_pad + end_trunc)
731 dev_info(&nd_pfn->dev, "%s alignment collision, truncate %d bytes\n",
732 dev_name(&ndns->dev), start_pad + end_trunc);
733
734 /*
735 * Note, we use 64 here for the standard size of struct page,
736 * debugging options may cause it to be larger in which case the
737 * implementation will limit the pfns advertised through
738 * ->direct_access() to those that are included in the memmap.
739 */
740 start = nsio->res.start + start_pad;
741 size = resource_size(&nsio->res);
742 npfns = PFN_SECTION_ALIGN_UP((size - start_pad - end_trunc - reserve)
743 / PAGE_SIZE);
744 if (nd_pfn->mode == PFN_MODE_PMEM) {
745 /*
746 * The altmap should be padded out to the block size used
747 * when populating the vmemmap. This *should* be equal to
748 * PMD_SIZE for most architectures.
749 */
750 offset = ALIGN(start + reserve + 64 * npfns,
751 max(nd_pfn->align, PMD_SIZE)) - start;
752 } else if (nd_pfn->mode == PFN_MODE_RAM)
753 offset = ALIGN(start + reserve, nd_pfn->align) - start;
754 else
755 return -ENXIO;
756
757 if (offset + start_pad + end_trunc >= size) {
758 dev_err(&nd_pfn->dev, "%s unable to satisfy requested alignment\n",
759 dev_name(&ndns->dev));
760 return -ENXIO;
761 }
762
763 npfns = (size - offset - start_pad - end_trunc) / SZ_4K;
764 pfn_sb->mode = cpu_to_le32(nd_pfn->mode);
765 pfn_sb->dataoff = cpu_to_le64(offset);
766 pfn_sb->npfns = cpu_to_le64(npfns);
767 memcpy(pfn_sb->signature, sig, PFN_SIG_LEN);
768 memcpy(pfn_sb->uuid, nd_pfn->uuid, 16);
769 memcpy(pfn_sb->parent_uuid, nd_dev_to_uuid(&ndns->dev), 16);
770 pfn_sb->version_major = cpu_to_le16(1);
771 pfn_sb->version_minor = cpu_to_le16(2);
772 pfn_sb->start_pad = cpu_to_le32(start_pad);
773 pfn_sb->end_trunc = cpu_to_le32(end_trunc);
774 pfn_sb->align = cpu_to_le32(nd_pfn->align);
775 checksum = nd_sb_checksum((struct nd_gen_sb *) pfn_sb);
776 pfn_sb->checksum = cpu_to_le64(checksum);
777
778 return nvdimm_write_bytes(ndns, SZ_4K, pfn_sb, sizeof(*pfn_sb), 0);
779}
780
781/*
782 * Determine the effective resource range and vmem_altmap from an nd_pfn
783 * instance.
784 */
785int nvdimm_setup_pfn(struct nd_pfn *nd_pfn, struct dev_pagemap *pgmap)
786{
787 int rc;
788
789 if (!nd_pfn->uuid || !nd_pfn->ndns)
790 return -ENODEV;
791
792 rc = nd_pfn_init(nd_pfn);
793 if (rc)
794 return rc;
795
796 /* we need a valid pfn_sb before we can init a dev_pagemap */
797 return __nvdimm_setup_pfn(nd_pfn, pgmap);
798}
799EXPORT_SYMBOL_GPL(nvdimm_setup_pfn);
800