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/genhd.h> 9 #include <linux/sizes.h> 10 #include <linux/slab.h> 11 #include <linux/fs.h> 12 #include <linux/mm.h> 13 #include "nd-core.h" 14 #include "pfn.h" 15 #include "nd.h" 16 17 static void nd_pfn_release(struct device *dev) 18 { 19 struct nd_region *nd_region = to_nd_region(dev->parent); 20 struct nd_pfn *nd_pfn = to_nd_pfn(dev); 21 22 dev_dbg(dev, "trace\n"); 23 nd_detach_ndns(&nd_pfn->dev, &nd_pfn->ndns); 24 ida_simple_remove(&nd_region->pfn_ida, nd_pfn->id); 25 kfree(nd_pfn->uuid); 26 kfree(nd_pfn); 27 } 28 29 static struct device_type nd_pfn_device_type = { 30 .name = "nd_pfn", 31 .release = nd_pfn_release, 32 }; 33 34 bool is_nd_pfn(struct device *dev) 35 { 36 return dev ? dev->type == &nd_pfn_device_type : false; 37 } 38 EXPORT_SYMBOL(is_nd_pfn); 39 40 struct nd_pfn *to_nd_pfn(struct device *dev) 41 { 42 struct nd_pfn *nd_pfn = container_of(dev, struct nd_pfn, dev); 43 44 WARN_ON(!is_nd_pfn(dev)); 45 return nd_pfn; 46 } 47 EXPORT_SYMBOL(to_nd_pfn); 48 49 static ssize_t mode_show(struct device *dev, 50 struct device_attribute *attr, char *buf) 51 { 52 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); 53 54 switch (nd_pfn->mode) { 55 case PFN_MODE_RAM: 56 return sprintf(buf, "ram\n"); 57 case PFN_MODE_PMEM: 58 return sprintf(buf, "pmem\n"); 59 default: 60 return sprintf(buf, "none\n"); 61 } 62 } 63 64 static ssize_t mode_store(struct device *dev, 65 struct device_attribute *attr, const char *buf, size_t len) 66 { 67 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); 68 ssize_t rc = 0; 69 70 nd_device_lock(dev); 71 nvdimm_bus_lock(dev); 72 if (dev->driver) 73 rc = -EBUSY; 74 else { 75 size_t n = len - 1; 76 77 if (strncmp(buf, "pmem\n", n) == 0 78 || strncmp(buf, "pmem", n) == 0) { 79 nd_pfn->mode = PFN_MODE_PMEM; 80 } else if (strncmp(buf, "ram\n", n) == 0 81 || strncmp(buf, "ram", n) == 0) 82 nd_pfn->mode = PFN_MODE_RAM; 83 else if (strncmp(buf, "none\n", n) == 0 84 || strncmp(buf, "none", n) == 0) 85 nd_pfn->mode = PFN_MODE_NONE; 86 else 87 rc = -EINVAL; 88 } 89 dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf, 90 buf[len - 1] == '\n' ? "" : "\n"); 91 nvdimm_bus_unlock(dev); 92 nd_device_unlock(dev); 93 94 return rc ? rc : len; 95 } 96 static DEVICE_ATTR_RW(mode); 97 98 static ssize_t align_show(struct device *dev, 99 struct device_attribute *attr, char *buf) 100 { 101 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); 102 103 return sprintf(buf, "%ld\n", nd_pfn->align); 104 } 105 106 static const unsigned long *nd_pfn_supported_alignments(void) 107 { 108 /* 109 * This needs to be a non-static variable because the *_SIZE 110 * macros aren't always constants. 111 */ 112 const unsigned long supported_alignments[] = { 113 PAGE_SIZE, 114 #ifdef CONFIG_TRANSPARENT_HUGEPAGE 115 HPAGE_PMD_SIZE, 116 #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD 117 HPAGE_PUD_SIZE, 118 #endif 119 #endif 120 0, 121 }; 122 static unsigned long data[ARRAY_SIZE(supported_alignments)]; 123 124 memcpy(data, supported_alignments, sizeof(data)); 125 126 return data; 127 } 128 129 static ssize_t align_store(struct device *dev, 130 struct device_attribute *attr, const char *buf, size_t len) 131 { 132 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); 133 ssize_t rc; 134 135 nd_device_lock(dev); 136 nvdimm_bus_lock(dev); 137 rc = nd_size_select_store(dev, buf, &nd_pfn->align, 138 nd_pfn_supported_alignments()); 139 dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf, 140 buf[len - 1] == '\n' ? "" : "\n"); 141 nvdimm_bus_unlock(dev); 142 nd_device_unlock(dev); 143 144 return rc ? rc : len; 145 } 146 static DEVICE_ATTR_RW(align); 147 148 static ssize_t uuid_show(struct device *dev, 149 struct device_attribute *attr, char *buf) 150 { 151 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); 152 153 if (nd_pfn->uuid) 154 return sprintf(buf, "%pUb\n", nd_pfn->uuid); 155 return sprintf(buf, "\n"); 156 } 157 158 static ssize_t uuid_store(struct device *dev, 159 struct device_attribute *attr, const char *buf, size_t len) 160 { 161 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); 162 ssize_t rc; 163 164 nd_device_lock(dev); 165 rc = nd_uuid_store(dev, &nd_pfn->uuid, buf, len); 166 dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf, 167 buf[len - 1] == '\n' ? "" : "\n"); 168 nd_device_unlock(dev); 169 170 return rc ? rc : len; 171 } 172 static DEVICE_ATTR_RW(uuid); 173 174 static ssize_t namespace_show(struct device *dev, 175 struct device_attribute *attr, char *buf) 176 { 177 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); 178 ssize_t rc; 179 180 nvdimm_bus_lock(dev); 181 rc = sprintf(buf, "%s\n", nd_pfn->ndns 182 ? dev_name(&nd_pfn->ndns->dev) : ""); 183 nvdimm_bus_unlock(dev); 184 return rc; 185 } 186 187 static ssize_t namespace_store(struct device *dev, 188 struct device_attribute *attr, const char *buf, size_t len) 189 { 190 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); 191 ssize_t rc; 192 193 nd_device_lock(dev); 194 nvdimm_bus_lock(dev); 195 rc = nd_namespace_store(dev, &nd_pfn->ndns, buf, len); 196 dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf, 197 buf[len - 1] == '\n' ? "" : "\n"); 198 nvdimm_bus_unlock(dev); 199 nd_device_unlock(dev); 200 201 return rc; 202 } 203 static DEVICE_ATTR_RW(namespace); 204 205 static ssize_t resource_show(struct device *dev, 206 struct device_attribute *attr, char *buf) 207 { 208 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); 209 ssize_t rc; 210 211 nd_device_lock(dev); 212 if (dev->driver) { 213 struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb; 214 u64 offset = __le64_to_cpu(pfn_sb->dataoff); 215 struct nd_namespace_common *ndns = nd_pfn->ndns; 216 u32 start_pad = __le32_to_cpu(pfn_sb->start_pad); 217 struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev); 218 219 rc = sprintf(buf, "%#llx\n", (unsigned long long) nsio->res.start 220 + start_pad + offset); 221 } else { 222 /* no address to convey if the pfn instance is disabled */ 223 rc = -ENXIO; 224 } 225 nd_device_unlock(dev); 226 227 return rc; 228 } 229 static DEVICE_ATTR_RO(resource); 230 231 static ssize_t size_show(struct device *dev, 232 struct device_attribute *attr, char *buf) 233 { 234 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); 235 ssize_t rc; 236 237 nd_device_lock(dev); 238 if (dev->driver) { 239 struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb; 240 u64 offset = __le64_to_cpu(pfn_sb->dataoff); 241 struct nd_namespace_common *ndns = nd_pfn->ndns; 242 u32 start_pad = __le32_to_cpu(pfn_sb->start_pad); 243 u32 end_trunc = __le32_to_cpu(pfn_sb->end_trunc); 244 struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev); 245 246 rc = sprintf(buf, "%llu\n", (unsigned long long) 247 resource_size(&nsio->res) - start_pad 248 - end_trunc - offset); 249 } else { 250 /* no size to convey if the pfn instance is disabled */ 251 rc = -ENXIO; 252 } 253 nd_device_unlock(dev); 254 255 return rc; 256 } 257 static DEVICE_ATTR_RO(size); 258 259 static ssize_t supported_alignments_show(struct device *dev, 260 struct device_attribute *attr, char *buf) 261 { 262 return nd_size_select_show(0, nd_pfn_supported_alignments(), buf); 263 } 264 static DEVICE_ATTR_RO(supported_alignments); 265 266 static struct attribute *nd_pfn_attributes[] = { 267 &dev_attr_mode.attr, 268 &dev_attr_namespace.attr, 269 &dev_attr_uuid.attr, 270 &dev_attr_align.attr, 271 &dev_attr_resource.attr, 272 &dev_attr_size.attr, 273 &dev_attr_supported_alignments.attr, 274 NULL, 275 }; 276 277 static umode_t pfn_visible(struct kobject *kobj, struct attribute *a, int n) 278 { 279 if (a == &dev_attr_resource.attr) 280 return 0400; 281 return a->mode; 282 } 283 284 struct attribute_group nd_pfn_attribute_group = { 285 .attrs = nd_pfn_attributes, 286 .is_visible = pfn_visible, 287 }; 288 289 static const struct attribute_group *nd_pfn_attribute_groups[] = { 290 &nd_pfn_attribute_group, 291 &nd_device_attribute_group, 292 &nd_numa_attribute_group, 293 NULL, 294 }; 295 296 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 = PFN_DEFAULT_ALIGNMENT; 306 dev = &nd_pfn->dev; 307 device_initialize(&nd_pfn->dev); 308 if (ndns && !__nd_attach_ndns(&nd_pfn->dev, ndns, &nd_pfn->ndns)) { 309 dev_dbg(&ndns->dev, "failed, already claimed by %s\n", 310 dev_name(ndns->claim)); 311 put_device(dev); 312 return NULL; 313 } 314 return dev; 315 } 316 317 static struct nd_pfn *nd_pfn_alloc(struct nd_region *nd_region) 318 { 319 struct nd_pfn *nd_pfn; 320 struct device *dev; 321 322 nd_pfn = kzalloc(sizeof(*nd_pfn), GFP_KERNEL); 323 if (!nd_pfn) 324 return NULL; 325 326 nd_pfn->id = ida_simple_get(&nd_region->pfn_ida, 0, 0, GFP_KERNEL); 327 if (nd_pfn->id < 0) { 328 kfree(nd_pfn); 329 return NULL; 330 } 331 332 dev = &nd_pfn->dev; 333 dev_set_name(dev, "pfn%d.%d", nd_region->id, nd_pfn->id); 334 dev->groups = nd_pfn_attribute_groups; 335 dev->type = &nd_pfn_device_type; 336 dev->parent = &nd_region->dev; 337 338 return nd_pfn; 339 } 340 341 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 */ 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 do { 380 unsigned long zero_len; 381 u64 nsoff; 382 383 bb_present = badblocks_check(&nd_region->bb, meta_start, 384 meta_num, &first_bad, &num_bad); 385 if (bb_present) { 386 dev_dbg(&nd_pfn->dev, "meta: %x badblocks at %llx\n", 387 num_bad, first_bad); 388 nsoff = ALIGN_DOWN((nd_region->ndr_start 389 + (first_bad << 9)) - nsio->res.start, 390 PAGE_SIZE); 391 zero_len = ALIGN(num_bad << 9, PAGE_SIZE); 392 while (zero_len) { 393 unsigned long chunk = min(zero_len, PAGE_SIZE); 394 395 rc = nvdimm_write_bytes(ndns, nsoff, zero_page, 396 chunk, 0); 397 if (rc) 398 break; 399 400 zero_len -= chunk; 401 nsoff += chunk; 402 } 403 if (rc) { 404 dev_err(&nd_pfn->dev, 405 "error clearing %x badblocks at %llx\n", 406 num_bad, first_bad); 407 return rc; 408 } 409 } 410 } while (bb_present); 411 412 return 0; 413 } 414 415 /** 416 * nd_pfn_validate - read and validate info-block 417 * @nd_pfn: fsdax namespace runtime state / properties 418 * @sig: 'devdax' or 'fsdax' signature 419 * 420 * Upon return the info-block buffer contents (->pfn_sb) are 421 * indeterminate when validation fails, and a coherent info-block 422 * otherwise. 423 */ 424 int nd_pfn_validate(struct nd_pfn *nd_pfn, const char *sig) 425 { 426 u64 checksum, offset; 427 enum nd_pfn_mode mode; 428 struct nd_namespace_io *nsio; 429 unsigned long align, start_pad; 430 struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb; 431 struct nd_namespace_common *ndns = nd_pfn->ndns; 432 const u8 *parent_uuid = nd_dev_to_uuid(&ndns->dev); 433 434 if (!pfn_sb || !ndns) 435 return -ENODEV; 436 437 if (!is_memory(nd_pfn->dev.parent)) 438 return -ENODEV; 439 440 if (nvdimm_read_bytes(ndns, SZ_4K, pfn_sb, sizeof(*pfn_sb), 0)) 441 return -ENXIO; 442 443 if (memcmp(pfn_sb->signature, sig, PFN_SIG_LEN) != 0) 444 return -ENODEV; 445 446 checksum = le64_to_cpu(pfn_sb->checksum); 447 pfn_sb->checksum = 0; 448 if (checksum != nd_sb_checksum((struct nd_gen_sb *) pfn_sb)) 449 return -ENODEV; 450 pfn_sb->checksum = cpu_to_le64(checksum); 451 452 if (memcmp(pfn_sb->parent_uuid, parent_uuid, 16) != 0) 453 return -ENODEV; 454 455 if (__le16_to_cpu(pfn_sb->version_minor) < 1) { 456 pfn_sb->start_pad = 0; 457 pfn_sb->end_trunc = 0; 458 } 459 460 if (__le16_to_cpu(pfn_sb->version_minor) < 2) 461 pfn_sb->align = 0; 462 463 if (__le16_to_cpu(pfn_sb->version_minor) < 4) { 464 pfn_sb->page_struct_size = cpu_to_le16(64); 465 pfn_sb->page_size = cpu_to_le32(PAGE_SIZE); 466 } 467 468 switch (le32_to_cpu(pfn_sb->mode)) { 469 case PFN_MODE_RAM: 470 case PFN_MODE_PMEM: 471 break; 472 default: 473 return -ENXIO; 474 } 475 476 align = le32_to_cpu(pfn_sb->align); 477 offset = le64_to_cpu(pfn_sb->dataoff); 478 start_pad = le32_to_cpu(pfn_sb->start_pad); 479 if (align == 0) 480 align = 1UL << ilog2(offset); 481 mode = le32_to_cpu(pfn_sb->mode); 482 483 if ((le32_to_cpu(pfn_sb->page_size) > PAGE_SIZE) && 484 (mode == PFN_MODE_PMEM)) { 485 dev_err(&nd_pfn->dev, 486 "init failed, page size mismatch %d\n", 487 le32_to_cpu(pfn_sb->page_size)); 488 return -EOPNOTSUPP; 489 } 490 491 if ((le16_to_cpu(pfn_sb->page_struct_size) < sizeof(struct page)) && 492 (mode == PFN_MODE_PMEM)) { 493 dev_err(&nd_pfn->dev, 494 "init failed, struct page size mismatch %d\n", 495 le16_to_cpu(pfn_sb->page_struct_size)); 496 return -EOPNOTSUPP; 497 } 498 499 if (!nd_pfn->uuid) { 500 /* 501 * When probing a namepace via nd_pfn_probe() the uuid 502 * is NULL (see: nd_pfn_devinit()) we init settings from 503 * pfn_sb 504 */ 505 nd_pfn->uuid = kmemdup(pfn_sb->uuid, 16, GFP_KERNEL); 506 if (!nd_pfn->uuid) 507 return -ENOMEM; 508 nd_pfn->align = align; 509 nd_pfn->mode = mode; 510 } else { 511 /* 512 * When probing a pfn / dax instance we validate the 513 * live settings against the pfn_sb 514 */ 515 if (memcmp(nd_pfn->uuid, pfn_sb->uuid, 16) != 0) 516 return -ENODEV; 517 518 /* 519 * If the uuid validates, but other settings mismatch 520 * return EINVAL because userspace has managed to change 521 * the configuration without specifying new 522 * identification. 523 */ 524 if (nd_pfn->align != align || nd_pfn->mode != mode) { 525 dev_err(&nd_pfn->dev, 526 "init failed, settings mismatch\n"); 527 dev_dbg(&nd_pfn->dev, "align: %lx:%lx mode: %d:%d\n", 528 nd_pfn->align, align, nd_pfn->mode, 529 mode); 530 return -EINVAL; 531 } 532 } 533 534 if (align > nvdimm_namespace_capacity(ndns)) { 535 dev_err(&nd_pfn->dev, "alignment: %lx exceeds capacity %llx\n", 536 align, nvdimm_namespace_capacity(ndns)); 537 return -EINVAL; 538 } 539 540 /* 541 * These warnings are verbose because they can only trigger in 542 * the case where the physical address alignment of the 543 * namespace has changed since the pfn superblock was 544 * established. 545 */ 546 nsio = to_nd_namespace_io(&ndns->dev); 547 if (offset >= resource_size(&nsio->res)) { 548 dev_err(&nd_pfn->dev, "pfn array size exceeds capacity of %s\n", 549 dev_name(&ndns->dev)); 550 return -EBUSY; 551 } 552 553 if ((align && !IS_ALIGNED(nsio->res.start + offset + start_pad, align)) 554 || !IS_ALIGNED(offset, PAGE_SIZE)) { 555 dev_err(&nd_pfn->dev, 556 "bad offset: %#llx dax disabled align: %#lx\n", 557 offset, align); 558 return -ENXIO; 559 } 560 561 return nd_pfn_clear_memmap_errors(nd_pfn); 562 } 563 EXPORT_SYMBOL(nd_pfn_validate); 564 565 int nd_pfn_probe(struct device *dev, struct nd_namespace_common *ndns) 566 { 567 int rc; 568 struct nd_pfn *nd_pfn; 569 struct device *pfn_dev; 570 struct nd_pfn_sb *pfn_sb; 571 struct nd_region *nd_region = to_nd_region(ndns->dev.parent); 572 573 if (ndns->force_raw) 574 return -ENODEV; 575 576 switch (ndns->claim_class) { 577 case NVDIMM_CCLASS_NONE: 578 case NVDIMM_CCLASS_PFN: 579 break; 580 default: 581 return -ENODEV; 582 } 583 584 nvdimm_bus_lock(&ndns->dev); 585 nd_pfn = nd_pfn_alloc(nd_region); 586 pfn_dev = nd_pfn_devinit(nd_pfn, ndns); 587 nvdimm_bus_unlock(&ndns->dev); 588 if (!pfn_dev) 589 return -ENOMEM; 590 pfn_sb = devm_kmalloc(dev, sizeof(*pfn_sb), GFP_KERNEL); 591 nd_pfn = to_nd_pfn(pfn_dev); 592 nd_pfn->pfn_sb = pfn_sb; 593 rc = nd_pfn_validate(nd_pfn, PFN_SIG); 594 dev_dbg(dev, "pfn: %s\n", rc == 0 ? dev_name(pfn_dev) : "<none>"); 595 if (rc < 0) { 596 nd_detach_ndns(pfn_dev, &nd_pfn->ndns); 597 put_device(pfn_dev); 598 } else 599 __nd_device_register(pfn_dev); 600 601 return rc; 602 } 603 EXPORT_SYMBOL(nd_pfn_probe); 604 605 static u32 info_block_reserve(void) 606 { 607 return ALIGN(SZ_8K, PAGE_SIZE); 608 } 609 610 /* 611 * We hotplug memory at sub-section granularity, pad the reserved area 612 * from the previous section base to the namespace base address. 613 */ 614 static unsigned long init_altmap_base(resource_size_t base) 615 { 616 unsigned long base_pfn = PHYS_PFN(base); 617 618 return SUBSECTION_ALIGN_DOWN(base_pfn); 619 } 620 621 static unsigned long init_altmap_reserve(resource_size_t base) 622 { 623 unsigned long reserve = info_block_reserve() >> PAGE_SHIFT; 624 unsigned long base_pfn = PHYS_PFN(base); 625 626 reserve += base_pfn - SUBSECTION_ALIGN_DOWN(base_pfn); 627 return reserve; 628 } 629 630 static int __nvdimm_setup_pfn(struct nd_pfn *nd_pfn, struct dev_pagemap *pgmap) 631 { 632 struct resource *res = &pgmap->res; 633 struct vmem_altmap *altmap = &pgmap->altmap; 634 struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb; 635 u64 offset = le64_to_cpu(pfn_sb->dataoff); 636 u32 start_pad = __le32_to_cpu(pfn_sb->start_pad); 637 u32 end_trunc = __le32_to_cpu(pfn_sb->end_trunc); 638 u32 reserve = info_block_reserve(); 639 struct nd_namespace_common *ndns = nd_pfn->ndns; 640 struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev); 641 resource_size_t base = nsio->res.start + start_pad; 642 struct vmem_altmap __altmap = { 643 .base_pfn = init_altmap_base(base), 644 .reserve = init_altmap_reserve(base), 645 }; 646 647 memcpy(res, &nsio->res, sizeof(*res)); 648 res->start += start_pad; 649 res->end -= end_trunc; 650 651 if (nd_pfn->mode == PFN_MODE_RAM) { 652 if (offset < reserve) 653 return -EINVAL; 654 nd_pfn->npfns = le64_to_cpu(pfn_sb->npfns); 655 } else if (nd_pfn->mode == PFN_MODE_PMEM) { 656 nd_pfn->npfns = PHYS_PFN((resource_size(res) - offset)); 657 if (le64_to_cpu(nd_pfn->pfn_sb->npfns) > nd_pfn->npfns) 658 dev_info(&nd_pfn->dev, 659 "number of pfns truncated from %lld to %ld\n", 660 le64_to_cpu(nd_pfn->pfn_sb->npfns), 661 nd_pfn->npfns); 662 memcpy(altmap, &__altmap, sizeof(*altmap)); 663 altmap->free = PHYS_PFN(offset - reserve); 664 altmap->alloc = 0; 665 pgmap->flags |= PGMAP_ALTMAP_VALID; 666 } else 667 return -ENXIO; 668 669 return 0; 670 } 671 672 static int nd_pfn_init(struct nd_pfn *nd_pfn) 673 { 674 struct nd_namespace_common *ndns = nd_pfn->ndns; 675 struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev); 676 resource_size_t start, size; 677 struct nd_region *nd_region; 678 unsigned long npfns, align; 679 u32 end_trunc; 680 struct nd_pfn_sb *pfn_sb; 681 phys_addr_t offset; 682 const char *sig; 683 u64 checksum; 684 int rc; 685 686 pfn_sb = devm_kmalloc(&nd_pfn->dev, sizeof(*pfn_sb), GFP_KERNEL); 687 if (!pfn_sb) 688 return -ENOMEM; 689 690 nd_pfn->pfn_sb = pfn_sb; 691 if (is_nd_dax(&nd_pfn->dev)) 692 sig = DAX_SIG; 693 else 694 sig = PFN_SIG; 695 696 rc = nd_pfn_validate(nd_pfn, sig); 697 if (rc != -ENODEV) 698 return rc; 699 700 /* no info block, do init */; 701 memset(pfn_sb, 0, sizeof(*pfn_sb)); 702 703 nd_region = to_nd_region(nd_pfn->dev.parent); 704 if (nd_region->ro) { 705 dev_info(&nd_pfn->dev, 706 "%s is read-only, unable to init metadata\n", 707 dev_name(&nd_region->dev)); 708 return -ENXIO; 709 } 710 711 /* 712 * Note, we use 64 here for the standard size of struct page, 713 * debugging options may cause it to be larger in which case the 714 * implementation will limit the pfns advertised through 715 * ->direct_access() to those that are included in the memmap. 716 */ 717 start = nsio->res.start; 718 size = resource_size(&nsio->res); 719 npfns = PHYS_PFN(size - SZ_8K); 720 align = max(nd_pfn->align, (1UL << SUBSECTION_SHIFT)); 721 end_trunc = start + size - ALIGN_DOWN(start + size, align); 722 if (nd_pfn->mode == PFN_MODE_PMEM) { 723 /* 724 * The altmap should be padded out to the block size used 725 * when populating the vmemmap. This *should* be equal to 726 * PMD_SIZE for most architectures. 727 * 728 * Also make sure size of struct page is less than 64. We 729 * want to make sure we use large enough size here so that 730 * we don't have a dynamic reserve space depending on 731 * struct page size. But we also want to make sure we notice 732 * when we end up adding new elements to struct page. 733 */ 734 BUILD_BUG_ON(sizeof(struct page) > MAX_STRUCT_PAGE_SIZE); 735 offset = ALIGN(start + SZ_8K + MAX_STRUCT_PAGE_SIZE * npfns, align) 736 - start; 737 } else if (nd_pfn->mode == PFN_MODE_RAM) 738 offset = ALIGN(start + SZ_8K, align) - start; 739 else 740 return -ENXIO; 741 742 if (offset >= size) { 743 dev_err(&nd_pfn->dev, "%s unable to satisfy requested alignment\n", 744 dev_name(&ndns->dev)); 745 return -ENXIO; 746 } 747 748 npfns = PHYS_PFN(size - offset - end_trunc); 749 pfn_sb->mode = cpu_to_le32(nd_pfn->mode); 750 pfn_sb->dataoff = cpu_to_le64(offset); 751 pfn_sb->npfns = cpu_to_le64(npfns); 752 memcpy(pfn_sb->signature, sig, PFN_SIG_LEN); 753 memcpy(pfn_sb->uuid, nd_pfn->uuid, 16); 754 memcpy(pfn_sb->parent_uuid, nd_dev_to_uuid(&ndns->dev), 16); 755 pfn_sb->version_major = cpu_to_le16(1); 756 pfn_sb->version_minor = cpu_to_le16(4); 757 pfn_sb->end_trunc = cpu_to_le32(end_trunc); 758 pfn_sb->align = cpu_to_le32(nd_pfn->align); 759 pfn_sb->page_struct_size = cpu_to_le16(MAX_STRUCT_PAGE_SIZE); 760 pfn_sb->page_size = cpu_to_le32(PAGE_SIZE); 761 checksum = nd_sb_checksum((struct nd_gen_sb *) pfn_sb); 762 pfn_sb->checksum = cpu_to_le64(checksum); 763 764 return nvdimm_write_bytes(ndns, SZ_4K, pfn_sb, sizeof(*pfn_sb), 0); 765 } 766 767 /* 768 * Determine the effective resource range and vmem_altmap from an nd_pfn 769 * instance. 770 */ 771 int nvdimm_setup_pfn(struct nd_pfn *nd_pfn, struct dev_pagemap *pgmap) 772 { 773 int rc; 774 775 if (!nd_pfn->uuid || !nd_pfn->ndns) 776 return -ENODEV; 777 778 rc = nd_pfn_init(nd_pfn); 779 if (rc) 780 return rc; 781 782 /* we need a valid pfn_sb before we can init a dev_pagemap */ 783 return __nvdimm_setup_pfn(nd_pfn, pgmap); 784 } 785 EXPORT_SYMBOL_GPL(nvdimm_setup_pfn); 786