2 * Copyright(c) 2013-2016 Intel Corporation. All rights reserved.
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.
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.
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>
25 static void nd_pfn_release(struct device *dev)
27 struct nd_region *nd_region = to_nd_region(dev->parent);
28 struct nd_pfn *nd_pfn = to_nd_pfn(dev);
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);
37 static struct device_type nd_pfn_device_type = {
39 .release = nd_pfn_release,
42 bool is_nd_pfn(struct device *dev)
44 return dev ? dev->type == &nd_pfn_device_type : false;
46 EXPORT_SYMBOL(is_nd_pfn);
48 struct nd_pfn *to_nd_pfn(struct device *dev)
50 struct nd_pfn *nd_pfn = container_of(dev, struct nd_pfn, dev);
52 WARN_ON(!is_nd_pfn(dev));
55 EXPORT_SYMBOL(to_nd_pfn);
57 static ssize_t mode_show(struct device *dev,
58 struct device_attribute *attr, char *buf)
60 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
62 switch (nd_pfn->mode) {
64 return sprintf(buf, "ram\n");
66 return sprintf(buf, "pmem\n");
68 return sprintf(buf, "none\n");
72 static ssize_t mode_store(struct device *dev,
73 struct device_attribute *attr, const char *buf, size_t len)
75 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
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;
97 dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
98 buf[len - 1] == '\n' ? "" : "\n");
99 nvdimm_bus_unlock(dev);
102 return rc ? rc : len;
104 static DEVICE_ATTR_RW(mode);
106 static ssize_t align_show(struct device *dev,
107 struct device_attribute *attr, char *buf)
109 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
111 return sprintf(buf, "%ld\n", nd_pfn->align);
114 static const unsigned long *nd_pfn_supported_alignments(void)
117 * This needs to be a non-static variable because the *_SIZE
118 * macros aren't always constants.
120 const unsigned long supported_alignments[] = {
122 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
124 #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
130 static unsigned long data[ARRAY_SIZE(supported_alignments)];
132 memcpy(data, supported_alignments, sizeof(data));
137 static ssize_t align_store(struct device *dev,
138 struct device_attribute *attr, const char *buf, size_t len)
140 struct nd_pfn *nd_pfn = to_nd_pfn_safe(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);
152 return rc ? rc : len;
154 static DEVICE_ATTR_RW(align);
156 static ssize_t uuid_show(struct device *dev,
157 struct device_attribute *attr, char *buf)
159 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
162 return sprintf(buf, "%pUb\n", nd_pfn->uuid);
163 return sprintf(buf, "\n");
166 static ssize_t uuid_store(struct device *dev,
167 struct device_attribute *attr, const char *buf, size_t len)
169 struct nd_pfn *nd_pfn = to_nd_pfn_safe(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");
178 return rc ? rc : len;
180 static DEVICE_ATTR_RW(uuid);
182 static ssize_t namespace_show(struct device *dev,
183 struct device_attribute *attr, char *buf)
185 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
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);
195 static ssize_t namespace_store(struct device *dev,
196 struct device_attribute *attr, const char *buf, size_t len)
198 struct nd_pfn *nd_pfn = to_nd_pfn_safe(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);
211 static DEVICE_ATTR_RW(namespace);
213 static ssize_t resource_show(struct device *dev,
214 struct device_attribute *attr, char *buf)
216 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
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);
227 rc = sprintf(buf, "%#llx\n", (unsigned long long) nsio->res.start
228 + start_pad + offset);
230 /* no address to convey if the pfn instance is disabled */
237 static DEVICE_ATTR_RO(resource);
239 static ssize_t size_show(struct device *dev,
240 struct device_attribute *attr, char *buf)
242 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
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);
254 rc = sprintf(buf, "%llu\n", (unsigned long long)
255 resource_size(&nsio->res) - start_pad
256 - end_trunc - offset);
258 /* no size to convey if the pfn instance is disabled */
265 static DEVICE_ATTR_RO(size);
267 static ssize_t supported_alignments_show(struct device *dev,
268 struct device_attribute *attr, char *buf)
270 return nd_size_select_show(0, nd_pfn_supported_alignments(), buf);
272 static DEVICE_ATTR_RO(supported_alignments);
274 static struct attribute *nd_pfn_attributes[] = {
276 &dev_attr_namespace.attr,
278 &dev_attr_align.attr,
279 &dev_attr_resource.attr,
281 &dev_attr_supported_alignments.attr,
285 static umode_t pfn_visible(struct kobject *kobj, struct attribute *a, int n)
287 if (a == &dev_attr_resource.attr)
292 struct attribute_group nd_pfn_attribute_group = {
293 .attrs = nd_pfn_attributes,
294 .is_visible = pfn_visible,
297 static const struct attribute_group *nd_pfn_attribute_groups[] = {
298 &nd_pfn_attribute_group,
299 &nd_device_attribute_group,
300 &nd_numa_attribute_group,
304 struct device *nd_pfn_devinit(struct nd_pfn *nd_pfn,
305 struct nd_namespace_common *ndns)
312 nd_pfn->mode = PFN_MODE_NONE;
313 nd_pfn->align = PFN_DEFAULT_ALIGNMENT;
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));
325 static struct nd_pfn *nd_pfn_alloc(struct nd_region *nd_region)
327 struct nd_pfn *nd_pfn;
330 nd_pfn = kzalloc(sizeof(*nd_pfn), GFP_KERNEL);
334 nd_pfn->id = ida_simple_get(&nd_region->pfn_ida, 0, 0, GFP_KERNEL);
335 if (nd_pfn->id < 0) {
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;
349 struct device *nd_pfn_create(struct nd_region *nd_region)
351 struct nd_pfn *nd_pfn;
354 if (!is_memory(&nd_region->dev))
357 nd_pfn = nd_pfn_alloc(nd_region);
358 dev = nd_pfn_devinit(nd_pfn, NULL);
360 __nd_device_register(dev);
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.
370 static int nd_pfn_clear_memmap_errors(struct nd_pfn *nd_pfn)
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;
380 if (nd_pfn->mode != PFN_MODE_PMEM)
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;
388 unsigned long zero_len;
391 bb_present = badblocks_check(&nd_region->bb, meta_start,
392 meta_num, &first_bad, &num_bad);
394 dev_dbg(&nd_pfn->dev, "meta: %x badblocks at %lx\n",
396 nsoff = ALIGN_DOWN((nd_region->ndr_start
397 + (first_bad << 9)) - nsio->res.start,
399 zero_len = ALIGN(num_bad << 9, PAGE_SIZE);
401 unsigned long chunk = min(zero_len, PAGE_SIZE);
403 rc = nvdimm_write_bytes(ndns, nsoff, zero_page,
412 dev_err(&nd_pfn->dev,
413 "error clearing %x badblocks at %lx\n",
418 } while (bb_present);
423 int nd_pfn_validate(struct nd_pfn *nd_pfn, const char *sig)
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);
433 if (!pfn_sb || !ndns)
436 if (!is_memory(nd_pfn->dev.parent))
439 if (nvdimm_read_bytes(ndns, SZ_4K, pfn_sb, sizeof(*pfn_sb), 0))
442 if (memcmp(pfn_sb->signature, sig, PFN_SIG_LEN) != 0)
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))
449 pfn_sb->checksum = cpu_to_le64(checksum);
451 if (memcmp(pfn_sb->parent_uuid, parent_uuid, 16) != 0)
454 if (__le16_to_cpu(pfn_sb->version_minor) < 1) {
455 pfn_sb->start_pad = 0;
456 pfn_sb->end_trunc = 0;
459 if (__le16_to_cpu(pfn_sb->version_minor) < 2)
462 switch (le32_to_cpu(pfn_sb->mode)) {
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);
474 align = 1UL << ilog2(offset);
475 mode = le32_to_cpu(pfn_sb->mode);
479 * When probing a namepace via nd_pfn_probe() the uuid
480 * is NULL (see: nd_pfn_devinit()) we init settings from
483 nd_pfn->uuid = kmemdup(pfn_sb->uuid, 16, GFP_KERNEL);
486 nd_pfn->align = align;
490 * When probing a pfn / dax instance we validate the
491 * live settings against the pfn_sb
493 if (memcmp(nd_pfn->uuid, pfn_sb->uuid, 16) != 0)
497 * If the uuid validates, but other settings mismatch
498 * return EINVAL because userspace has managed to change
499 * the configuration without specifying new
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,
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));
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
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));
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",
539 return nd_pfn_clear_memmap_errors(nd_pfn);
541 EXPORT_SYMBOL(nd_pfn_validate);
543 int nd_pfn_probe(struct device *dev, struct nd_namespace_common *ndns)
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);
554 switch (ndns->claim_class) {
555 case NVDIMM_CCLASS_NONE:
556 case NVDIMM_CCLASS_PFN:
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);
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>");
574 nd_detach_ndns(pfn_dev, &nd_pfn->ndns);
577 __nd_device_register(pfn_dev);
581 EXPORT_SYMBOL(nd_pfn_probe);
583 static u32 info_block_reserve(void)
585 return ALIGN(SZ_8K, PAGE_SIZE);
589 * We hotplug memory at section granularity, pad the reserved area from
590 * the previous section base to the namespace base address.
592 static unsigned long init_altmap_base(resource_size_t base)
594 unsigned long base_pfn = PHYS_PFN(base);
596 return PFN_SECTION_ALIGN_DOWN(base_pfn);
599 static unsigned long init_altmap_reserve(resource_size_t base)
601 unsigned long reserve = info_block_reserve() >> PAGE_SHIFT;
602 unsigned long base_pfn = PHYS_PFN(base);
604 reserve += base_pfn - PFN_SECTION_ALIGN_DOWN(base_pfn);
608 static int __nvdimm_setup_pfn(struct nd_pfn *nd_pfn, struct dev_pagemap *pgmap)
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),
625 memcpy(res, &nsio->res, sizeof(*res));
626 res->start += start_pad;
627 res->end -= end_trunc;
629 if (nd_pfn->mode == PFN_MODE_RAM) {
630 if (offset < reserve)
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),
642 memcpy(altmap, &__altmap, sizeof(*altmap));
643 altmap->free = PHYS_PFN(offset - reserve);
645 pgmap->altmap_valid = true;
652 static u64 phys_pmem_align_down(struct nd_pfn *nd_pfn, u64 phys)
654 return min_t(u64, PHYS_SECTION_ALIGN_DOWN(phys),
655 ALIGN_DOWN(phys, nd_pfn->align));
659 * Check if pmem collides with 'System RAM', or other regions when
660 * section aligned. Trim it accordingly.
662 static void trim_pfn_device(struct nd_pfn *nd_pfn, u32 *start_pad, u32 *end_trunc)
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;
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;
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);
691 static int nd_pfn_init(struct nd_pfn *nd_pfn)
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;
705 pfn_sb = devm_kzalloc(&nd_pfn->dev, sizeof(*pfn_sb), GFP_KERNEL);
709 nd_pfn->pfn_sb = pfn_sb;
710 if (is_nd_dax(&nd_pfn->dev))
714 rc = nd_pfn_validate(nd_pfn, sig);
718 /* no info block, do init */;
719 nd_region = to_nd_region(nd_pfn->dev.parent);
721 dev_info(&nd_pfn->dev,
722 "%s is read-only, unable to init metadata\n",
723 dev_name(&nd_region->dev));
727 memset(pfn_sb, 0, sizeof(*pfn_sb));
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);
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.
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)
744 if (nd_pfn->mode == PFN_MODE_PMEM) {
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.
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;
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));
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);
778 return nvdimm_write_bytes(ndns, SZ_4K, pfn_sb, sizeof(*pfn_sb), 0);
782 * Determine the effective resource range and vmem_altmap from an nd_pfn
785 int nvdimm_setup_pfn(struct nd_pfn *nd_pfn, struct dev_pagemap *pgmap)
789 if (!nd_pfn->uuid || !nd_pfn->ndns)
792 rc = nd_pfn_init(nd_pfn);
796 /* we need a valid pfn_sb before we can init a dev_pagemap */
797 return __nvdimm_setup_pfn(nd_pfn, pgmap);
799 EXPORT_SYMBOL_GPL(nvdimm_setup_pfn);