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 struct nd_pfn *to_nd_pfn(struct device *dev) 30 { 31 struct nd_pfn *nd_pfn = container_of(dev, struct nd_pfn, dev); 32 33 WARN_ON(!is_nd_pfn(dev)); 34 return nd_pfn; 35 } 36 EXPORT_SYMBOL(to_nd_pfn); 37 38 static ssize_t mode_show(struct device *dev, 39 struct device_attribute *attr, char *buf) 40 { 41 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); 42 43 switch (nd_pfn->mode) { 44 case PFN_MODE_RAM: 45 return sprintf(buf, "ram\n"); 46 case PFN_MODE_PMEM: 47 return sprintf(buf, "pmem\n"); 48 default: 49 return sprintf(buf, "none\n"); 50 } 51 } 52 53 static ssize_t mode_store(struct device *dev, 54 struct device_attribute *attr, const char *buf, size_t len) 55 { 56 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); 57 ssize_t rc = 0; 58 59 nd_device_lock(dev); 60 nvdimm_bus_lock(dev); 61 if (dev->driver) 62 rc = -EBUSY; 63 else { 64 size_t n = len - 1; 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 } 78 dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf, 79 buf[len - 1] == '\n' ? "" : "\n"); 80 nvdimm_bus_unlock(dev); 81 nd_device_unlock(dev); 82 83 return rc ? rc : len; 84 } 85 static DEVICE_ATTR_RW(mode); 86 87 static ssize_t align_show(struct device *dev, 88 struct device_attribute *attr, char *buf) 89 { 90 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); 91 92 return sprintf(buf, "%ld\n", nd_pfn->align); 93 } 94 95 static unsigned long *nd_pfn_supported_alignments(unsigned long *alignments) 96 { 97 98 alignments[0] = PAGE_SIZE; 99 100 if (has_transparent_hugepage()) { 101 alignments[1] = HPAGE_PMD_SIZE; 102 if (IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)) 103 alignments[2] = HPAGE_PUD_SIZE; 104 } 105 106 return alignments; 107 } 108 109 /* 110 * Use pmd mapping if supported as default alignment 111 */ 112 static unsigned long nd_pfn_default_alignment(void) 113 { 114 115 if (has_transparent_hugepage()) 116 return HPAGE_PMD_SIZE; 117 return PAGE_SIZE; 118 } 119 120 static ssize_t align_store(struct device *dev, 121 struct device_attribute *attr, const char *buf, size_t len) 122 { 123 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); 124 unsigned long aligns[MAX_NVDIMM_ALIGN] = { [0] = 0, }; 125 ssize_t rc; 126 127 nd_device_lock(dev); 128 nvdimm_bus_lock(dev); 129 rc = nd_size_select_store(dev, buf, &nd_pfn->align, 130 nd_pfn_supported_alignments(aligns)); 131 dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf, 132 buf[len - 1] == '\n' ? "" : "\n"); 133 nvdimm_bus_unlock(dev); 134 nd_device_unlock(dev); 135 136 return rc ? rc : len; 137 } 138 static DEVICE_ATTR_RW(align); 139 140 static ssize_t uuid_show(struct device *dev, 141 struct device_attribute *attr, char *buf) 142 { 143 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); 144 145 if (nd_pfn->uuid) 146 return sprintf(buf, "%pUb\n", nd_pfn->uuid); 147 return sprintf(buf, "\n"); 148 } 149 150 static ssize_t uuid_store(struct device *dev, 151 struct device_attribute *attr, const char *buf, size_t len) 152 { 153 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); 154 ssize_t rc; 155 156 nd_device_lock(dev); 157 rc = nd_uuid_store(dev, &nd_pfn->uuid, buf, len); 158 dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf, 159 buf[len - 1] == '\n' ? "" : "\n"); 160 nd_device_unlock(dev); 161 162 return rc ? rc : len; 163 } 164 static DEVICE_ATTR_RW(uuid); 165 166 static ssize_t namespace_show(struct device *dev, 167 struct device_attribute *attr, char *buf) 168 { 169 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); 170 ssize_t rc; 171 172 nvdimm_bus_lock(dev); 173 rc = sprintf(buf, "%s\n", nd_pfn->ndns 174 ? dev_name(&nd_pfn->ndns->dev) : ""); 175 nvdimm_bus_unlock(dev); 176 return rc; 177 } 178 179 static ssize_t namespace_store(struct device *dev, 180 struct device_attribute *attr, const char *buf, size_t len) 181 { 182 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); 183 ssize_t rc; 184 185 nd_device_lock(dev); 186 nvdimm_bus_lock(dev); 187 rc = nd_namespace_store(dev, &nd_pfn->ndns, buf, len); 188 dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf, 189 buf[len - 1] == '\n' ? "" : "\n"); 190 nvdimm_bus_unlock(dev); 191 nd_device_unlock(dev); 192 193 return rc; 194 } 195 static DEVICE_ATTR_RW(namespace); 196 197 static ssize_t resource_show(struct device *dev, 198 struct device_attribute *attr, char *buf) 199 { 200 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); 201 ssize_t rc; 202 203 nd_device_lock(dev); 204 if (dev->driver) { 205 struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb; 206 u64 offset = __le64_to_cpu(pfn_sb->dataoff); 207 struct nd_namespace_common *ndns = nd_pfn->ndns; 208 u32 start_pad = __le32_to_cpu(pfn_sb->start_pad); 209 struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev); 210 211 rc = sprintf(buf, "%#llx\n", (unsigned long long) nsio->res.start 212 + start_pad + offset); 213 } else { 214 /* no address to convey if the pfn instance is disabled */ 215 rc = -ENXIO; 216 } 217 nd_device_unlock(dev); 218 219 return rc; 220 } 221 static DEVICE_ATTR_ADMIN_RO(resource); 222 223 static ssize_t size_show(struct device *dev, 224 struct device_attribute *attr, char *buf) 225 { 226 struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev); 227 ssize_t rc; 228 229 nd_device_lock(dev); 230 if (dev->driver) { 231 struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb; 232 u64 offset = __le64_to_cpu(pfn_sb->dataoff); 233 struct nd_namespace_common *ndns = nd_pfn->ndns; 234 u32 start_pad = __le32_to_cpu(pfn_sb->start_pad); 235 u32 end_trunc = __le32_to_cpu(pfn_sb->end_trunc); 236 struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev); 237 238 rc = sprintf(buf, "%llu\n", (unsigned long long) 239 resource_size(&nsio->res) - start_pad 240 - end_trunc - offset); 241 } else { 242 /* no size to convey if the pfn instance is disabled */ 243 rc = -ENXIO; 244 } 245 nd_device_unlock(dev); 246 247 return rc; 248 } 249 static DEVICE_ATTR_RO(size); 250 251 static ssize_t supported_alignments_show(struct device *dev, 252 struct device_attribute *attr, char *buf) 253 { 254 unsigned long aligns[MAX_NVDIMM_ALIGN] = { [0] = 0, }; 255 256 return nd_size_select_show(0, 257 nd_pfn_supported_alignments(aligns), buf); 258 } 259 static DEVICE_ATTR_RO(supported_alignments); 260 261 static struct attribute *nd_pfn_attributes[] = { 262 &dev_attr_mode.attr, 263 &dev_attr_namespace.attr, 264 &dev_attr_uuid.attr, 265 &dev_attr_align.attr, 266 &dev_attr_resource.attr, 267 &dev_attr_size.attr, 268 &dev_attr_supported_alignments.attr, 269 NULL, 270 }; 271 272 static struct attribute_group nd_pfn_attribute_group = { 273 .attrs = nd_pfn_attributes, 274 }; 275 276 const struct attribute_group *nd_pfn_attribute_groups[] = { 277 &nd_pfn_attribute_group, 278 &nd_device_attribute_group, 279 &nd_numa_attribute_group, 280 NULL, 281 }; 282 283 static const struct device_type nd_pfn_device_type = { 284 .name = "nd_pfn", 285 .release = nd_pfn_release, 286 .groups = nd_pfn_attribute_groups, 287 }; 288 289 bool is_nd_pfn(struct device *dev) 290 { 291 return dev ? dev->type == &nd_pfn_device_type : false; 292 } 293 EXPORT_SYMBOL(is_nd_pfn); 294 295 struct device *nd_pfn_devinit(struct nd_pfn *nd_pfn, 296 struct nd_namespace_common *ndns) 297 { 298 struct device *dev; 299 300 if (!nd_pfn) 301 return NULL; 302 303 nd_pfn->mode = PFN_MODE_NONE; 304 nd_pfn->align = nd_pfn_default_alignment(); 305 dev = &nd_pfn->dev; 306 device_initialize(&nd_pfn->dev); 307 if (ndns && !__nd_attach_ndns(&nd_pfn->dev, ndns, &nd_pfn->ndns)) { 308 dev_dbg(&ndns->dev, "failed, already claimed by %s\n", 309 dev_name(ndns->claim)); 310 put_device(dev); 311 return NULL; 312 } 313 return dev; 314 } 315 316 static struct nd_pfn *nd_pfn_alloc(struct nd_region *nd_region) 317 { 318 struct nd_pfn *nd_pfn; 319 struct device *dev; 320 321 nd_pfn = kzalloc(sizeof(*nd_pfn), GFP_KERNEL); 322 if (!nd_pfn) 323 return NULL; 324 325 nd_pfn->id = ida_simple_get(&nd_region->pfn_ida, 0, 0, GFP_KERNEL); 326 if (nd_pfn->id < 0) { 327 kfree(nd_pfn); 328 return NULL; 329 } 330 331 dev = &nd_pfn->dev; 332 dev_set_name(dev, "pfn%d.%d", nd_region->id, nd_pfn->id); 333 dev->type = &nd_pfn_device_type; 334 dev->parent = &nd_region->dev; 335 336 return nd_pfn; 337 } 338 339 struct device *nd_pfn_create(struct nd_region *nd_region) 340 { 341 struct nd_pfn *nd_pfn; 342 struct device *dev; 343 344 if (!is_memory(&nd_region->dev)) 345 return NULL; 346 347 nd_pfn = nd_pfn_alloc(nd_region); 348 dev = nd_pfn_devinit(nd_pfn, NULL); 349 350 __nd_device_register(dev); 351 return dev; 352 } 353 354 /* 355 * nd_pfn_clear_memmap_errors() clears any errors in the volatile memmap 356 * space associated with the namespace. If the memmap is set to DRAM, then 357 * this is a no-op. Since the memmap area is freshly initialized during 358 * probe, we have an opportunity to clear any badblocks in this area. 359 */ 360 static int nd_pfn_clear_memmap_errors(struct nd_pfn *nd_pfn) 361 { 362 struct nd_region *nd_region = to_nd_region(nd_pfn->dev.parent); 363 struct nd_namespace_common *ndns = nd_pfn->ndns; 364 void *zero_page = page_address(ZERO_PAGE(0)); 365 struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb; 366 int num_bad, meta_num, rc, bb_present; 367 sector_t first_bad, meta_start; 368 struct nd_namespace_io *nsio; 369 370 if (nd_pfn->mode != PFN_MODE_PMEM) 371 return 0; 372 373 nsio = to_nd_namespace_io(&ndns->dev); 374 meta_start = (SZ_4K + sizeof(*pfn_sb)) >> 9; 375 meta_num = (le64_to_cpu(pfn_sb->dataoff) >> 9) - meta_start; 376 377 /* 378 * re-enable the namespace with correct size so that we can access 379 * the device memmap area. 380 */ 381 devm_namespace_disable(&nd_pfn->dev, ndns); 382 rc = devm_namespace_enable(&nd_pfn->dev, ndns, le64_to_cpu(pfn_sb->dataoff)); 383 if (rc) 384 return rc; 385 386 do { 387 unsigned long zero_len; 388 u64 nsoff; 389 390 bb_present = badblocks_check(&nd_region->bb, meta_start, 391 meta_num, &first_bad, &num_bad); 392 if (bb_present) { 393 dev_dbg(&nd_pfn->dev, "meta: %x badblocks at %llx\n", 394 num_bad, first_bad); 395 nsoff = ALIGN_DOWN((nd_region->ndr_start 396 + (first_bad << 9)) - nsio->res.start, 397 PAGE_SIZE); 398 zero_len = ALIGN(num_bad << 9, PAGE_SIZE); 399 while (zero_len) { 400 unsigned long chunk = min(zero_len, PAGE_SIZE); 401 402 rc = nvdimm_write_bytes(ndns, nsoff, zero_page, 403 chunk, 0); 404 if (rc) 405 break; 406 407 zero_len -= chunk; 408 nsoff += chunk; 409 } 410 if (rc) { 411 dev_err(&nd_pfn->dev, 412 "error clearing %x badblocks at %llx\n", 413 num_bad, first_bad); 414 return rc; 415 } 416 } 417 } while (bb_present); 418 419 return 0; 420 } 421 422 static bool nd_supported_alignment(unsigned long align) 423 { 424 int i; 425 unsigned long supported[MAX_NVDIMM_ALIGN] = { [0] = 0, }; 426 427 if (align == 0) 428 return false; 429 430 nd_pfn_supported_alignments(supported); 431 for (i = 0; supported[i]; i++) 432 if (align == supported[i]) 433 return true; 434 return false; 435 } 436 437 /** 438 * nd_pfn_validate - read and validate info-block 439 * @nd_pfn: fsdax namespace runtime state / properties 440 * @sig: 'devdax' or 'fsdax' signature 441 * 442 * Upon return the info-block buffer contents (->pfn_sb) are 443 * indeterminate when validation fails, and a coherent info-block 444 * otherwise. 445 */ 446 int nd_pfn_validate(struct nd_pfn *nd_pfn, const char *sig) 447 { 448 u64 checksum, offset; 449 struct resource *res; 450 enum nd_pfn_mode mode; 451 struct nd_namespace_io *nsio; 452 unsigned long align, start_pad; 453 struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb; 454 struct nd_namespace_common *ndns = nd_pfn->ndns; 455 const u8 *parent_uuid = nd_dev_to_uuid(&ndns->dev); 456 457 if (!pfn_sb || !ndns) 458 return -ENODEV; 459 460 if (!is_memory(nd_pfn->dev.parent)) 461 return -ENODEV; 462 463 if (nvdimm_read_bytes(ndns, SZ_4K, pfn_sb, sizeof(*pfn_sb), 0)) 464 return -ENXIO; 465 466 if (memcmp(pfn_sb->signature, sig, PFN_SIG_LEN) != 0) 467 return -ENODEV; 468 469 checksum = le64_to_cpu(pfn_sb->checksum); 470 pfn_sb->checksum = 0; 471 if (checksum != nd_sb_checksum((struct nd_gen_sb *) pfn_sb)) 472 return -ENODEV; 473 pfn_sb->checksum = cpu_to_le64(checksum); 474 475 if (memcmp(pfn_sb->parent_uuid, parent_uuid, 16) != 0) 476 return -ENODEV; 477 478 if (__le16_to_cpu(pfn_sb->version_minor) < 1) { 479 pfn_sb->start_pad = 0; 480 pfn_sb->end_trunc = 0; 481 } 482 483 if (__le16_to_cpu(pfn_sb->version_minor) < 2) 484 pfn_sb->align = 0; 485 486 if (__le16_to_cpu(pfn_sb->version_minor) < 4) { 487 pfn_sb->page_struct_size = cpu_to_le16(64); 488 pfn_sb->page_size = cpu_to_le32(PAGE_SIZE); 489 } 490 491 switch (le32_to_cpu(pfn_sb->mode)) { 492 case PFN_MODE_RAM: 493 case PFN_MODE_PMEM: 494 break; 495 default: 496 return -ENXIO; 497 } 498 499 align = le32_to_cpu(pfn_sb->align); 500 offset = le64_to_cpu(pfn_sb->dataoff); 501 start_pad = le32_to_cpu(pfn_sb->start_pad); 502 if (align == 0) 503 align = 1UL << ilog2(offset); 504 mode = le32_to_cpu(pfn_sb->mode); 505 506 if ((le32_to_cpu(pfn_sb->page_size) > PAGE_SIZE) && 507 (mode == PFN_MODE_PMEM)) { 508 dev_err(&nd_pfn->dev, 509 "init failed, page size mismatch %d\n", 510 le32_to_cpu(pfn_sb->page_size)); 511 return -EOPNOTSUPP; 512 } 513 514 if ((le16_to_cpu(pfn_sb->page_struct_size) < sizeof(struct page)) && 515 (mode == PFN_MODE_PMEM)) { 516 dev_err(&nd_pfn->dev, 517 "init failed, struct page size mismatch %d\n", 518 le16_to_cpu(pfn_sb->page_struct_size)); 519 return -EOPNOTSUPP; 520 } 521 522 /* 523 * Check whether the we support the alignment. For Dax if the 524 * superblock alignment is not matching, we won't initialize 525 * the device. 526 */ 527 if (!nd_supported_alignment(align) && 528 !memcmp(pfn_sb->signature, DAX_SIG, PFN_SIG_LEN)) { 529 dev_err(&nd_pfn->dev, "init failed, alignment mismatch: " 530 "%ld:%ld\n", nd_pfn->align, align); 531 return -EOPNOTSUPP; 532 } 533 534 if (!nd_pfn->uuid) { 535 /* 536 * When probing a namepace via nd_pfn_probe() the uuid 537 * is NULL (see: nd_pfn_devinit()) we init settings from 538 * pfn_sb 539 */ 540 nd_pfn->uuid = kmemdup(pfn_sb->uuid, 16, GFP_KERNEL); 541 if (!nd_pfn->uuid) 542 return -ENOMEM; 543 nd_pfn->align = align; 544 nd_pfn->mode = mode; 545 } else { 546 /* 547 * When probing a pfn / dax instance we validate the 548 * live settings against the pfn_sb 549 */ 550 if (memcmp(nd_pfn->uuid, pfn_sb->uuid, 16) != 0) 551 return -ENODEV; 552 553 /* 554 * If the uuid validates, but other settings mismatch 555 * return EINVAL because userspace has managed to change 556 * the configuration without specifying new 557 * identification. 558 */ 559 if (nd_pfn->align != align || nd_pfn->mode != mode) { 560 dev_err(&nd_pfn->dev, 561 "init failed, settings mismatch\n"); 562 dev_dbg(&nd_pfn->dev, "align: %lx:%lx mode: %d:%d\n", 563 nd_pfn->align, align, nd_pfn->mode, 564 mode); 565 return -EOPNOTSUPP; 566 } 567 } 568 569 if (align > nvdimm_namespace_capacity(ndns)) { 570 dev_err(&nd_pfn->dev, "alignment: %lx exceeds capacity %llx\n", 571 align, nvdimm_namespace_capacity(ndns)); 572 return -EOPNOTSUPP; 573 } 574 575 /* 576 * These warnings are verbose because they can only trigger in 577 * the case where the physical address alignment of the 578 * namespace has changed since the pfn superblock was 579 * established. 580 */ 581 nsio = to_nd_namespace_io(&ndns->dev); 582 res = &nsio->res; 583 if (offset >= resource_size(res)) { 584 dev_err(&nd_pfn->dev, "pfn array size exceeds capacity of %s\n", 585 dev_name(&ndns->dev)); 586 return -EOPNOTSUPP; 587 } 588 589 if ((align && !IS_ALIGNED(res->start + offset + start_pad, align)) 590 || !IS_ALIGNED(offset, PAGE_SIZE)) { 591 dev_err(&nd_pfn->dev, 592 "bad offset: %#llx dax disabled align: %#lx\n", 593 offset, align); 594 return -EOPNOTSUPP; 595 } 596 597 if (!IS_ALIGNED(res->start + le32_to_cpu(pfn_sb->start_pad), 598 memremap_compat_align())) { 599 dev_err(&nd_pfn->dev, "resource start misaligned\n"); 600 return -EOPNOTSUPP; 601 } 602 603 if (!IS_ALIGNED(res->end + 1 - le32_to_cpu(pfn_sb->end_trunc), 604 memremap_compat_align())) { 605 dev_err(&nd_pfn->dev, "resource end misaligned\n"); 606 return -EOPNOTSUPP; 607 } 608 609 return 0; 610 } 611 EXPORT_SYMBOL(nd_pfn_validate); 612 613 int nd_pfn_probe(struct device *dev, struct nd_namespace_common *ndns) 614 { 615 int rc; 616 struct nd_pfn *nd_pfn; 617 struct device *pfn_dev; 618 struct nd_pfn_sb *pfn_sb; 619 struct nd_region *nd_region = to_nd_region(ndns->dev.parent); 620 621 if (ndns->force_raw) 622 return -ENODEV; 623 624 switch (ndns->claim_class) { 625 case NVDIMM_CCLASS_NONE: 626 case NVDIMM_CCLASS_PFN: 627 break; 628 default: 629 return -ENODEV; 630 } 631 632 nvdimm_bus_lock(&ndns->dev); 633 nd_pfn = nd_pfn_alloc(nd_region); 634 pfn_dev = nd_pfn_devinit(nd_pfn, ndns); 635 nvdimm_bus_unlock(&ndns->dev); 636 if (!pfn_dev) 637 return -ENOMEM; 638 pfn_sb = devm_kmalloc(dev, sizeof(*pfn_sb), GFP_KERNEL); 639 nd_pfn = to_nd_pfn(pfn_dev); 640 nd_pfn->pfn_sb = pfn_sb; 641 rc = nd_pfn_validate(nd_pfn, PFN_SIG); 642 dev_dbg(dev, "pfn: %s\n", rc == 0 ? dev_name(pfn_dev) : "<none>"); 643 if (rc < 0) { 644 nd_detach_ndns(pfn_dev, &nd_pfn->ndns); 645 put_device(pfn_dev); 646 } else 647 __nd_device_register(pfn_dev); 648 649 return rc; 650 } 651 EXPORT_SYMBOL(nd_pfn_probe); 652 653 /* 654 * We hotplug memory at sub-section granularity, pad the reserved area 655 * from the previous section base to the namespace base address. 656 */ 657 static unsigned long init_altmap_base(resource_size_t base) 658 { 659 unsigned long base_pfn = PHYS_PFN(base); 660 661 return SUBSECTION_ALIGN_DOWN(base_pfn); 662 } 663 664 static unsigned long init_altmap_reserve(resource_size_t base) 665 { 666 unsigned long reserve = nd_info_block_reserve() >> PAGE_SHIFT; 667 unsigned long base_pfn = PHYS_PFN(base); 668 669 reserve += base_pfn - SUBSECTION_ALIGN_DOWN(base_pfn); 670 return reserve; 671 } 672 673 static int __nvdimm_setup_pfn(struct nd_pfn *nd_pfn, struct dev_pagemap *pgmap) 674 { 675 struct resource *res = &pgmap->res; 676 struct vmem_altmap *altmap = &pgmap->altmap; 677 struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb; 678 u64 offset = le64_to_cpu(pfn_sb->dataoff); 679 u32 start_pad = __le32_to_cpu(pfn_sb->start_pad); 680 u32 end_trunc = __le32_to_cpu(pfn_sb->end_trunc); 681 u32 reserve = nd_info_block_reserve(); 682 struct nd_namespace_common *ndns = nd_pfn->ndns; 683 struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev); 684 resource_size_t base = nsio->res.start + start_pad; 685 resource_size_t end = nsio->res.end - end_trunc; 686 struct vmem_altmap __altmap = { 687 .base_pfn = init_altmap_base(base), 688 .reserve = init_altmap_reserve(base), 689 .end_pfn = PHYS_PFN(end), 690 }; 691 692 memcpy(res, &nsio->res, sizeof(*res)); 693 res->start += start_pad; 694 res->end -= end_trunc; 695 696 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((resource_size(res) - 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 } 716 717 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 /* 759 * Note, we use 64 here for the standard size of struct page, 760 * debugging options may cause it to be larger in which case the 761 * implementation will limit the pfns advertised through 762 * ->direct_access() to those that are included in the memmap. 763 */ 764 start = nsio->res.start; 765 size = resource_size(&nsio->res); 766 npfns = PHYS_PFN(size - SZ_8K); 767 align = max(nd_pfn->align, memremap_compat_align()); 768 769 /* 770 * When @start is misaligned fail namespace creation. See 771 * the 'struct nd_pfn_sb' commentary on why ->start_pad is not 772 * an option. 773 */ 774 if (!IS_ALIGNED(start, memremap_compat_align())) { 775 dev_err(&nd_pfn->dev, "%s: start %pa misaligned to %#lx\n", 776 dev_name(&ndns->dev), &start, 777 memremap_compat_align()); 778 return -EINVAL; 779 } 780 end_trunc = start + size - ALIGN_DOWN(start + size, align); 781 if (nd_pfn->mode == PFN_MODE_PMEM) { 782 /* 783 * The altmap should be padded out to the block size used 784 * when populating the vmemmap. This *should* be equal to 785 * PMD_SIZE for most architectures. 786 * 787 * Also make sure size of struct page is less than 64. We 788 * want to make sure we use large enough size here so that 789 * we don't have a dynamic reserve space depending on 790 * struct page size. But we also want to make sure we notice 791 * when we end up adding new elements to struct page. 792 */ 793 BUILD_BUG_ON(sizeof(struct page) > MAX_STRUCT_PAGE_SIZE); 794 offset = ALIGN(start + SZ_8K + MAX_STRUCT_PAGE_SIZE * npfns, align) 795 - start; 796 } else if (nd_pfn->mode == PFN_MODE_RAM) 797 offset = ALIGN(start + SZ_8K, align) - start; 798 else 799 return -ENXIO; 800 801 if (offset >= size) { 802 dev_err(&nd_pfn->dev, "%s unable to satisfy requested alignment\n", 803 dev_name(&ndns->dev)); 804 return -ENXIO; 805 } 806 807 npfns = PHYS_PFN(size - offset - end_trunc); 808 pfn_sb->mode = cpu_to_le32(nd_pfn->mode); 809 pfn_sb->dataoff = cpu_to_le64(offset); 810 pfn_sb->npfns = cpu_to_le64(npfns); 811 memcpy(pfn_sb->signature, sig, PFN_SIG_LEN); 812 memcpy(pfn_sb->uuid, nd_pfn->uuid, 16); 813 memcpy(pfn_sb->parent_uuid, nd_dev_to_uuid(&ndns->dev), 16); 814 pfn_sb->version_major = cpu_to_le16(1); 815 pfn_sb->version_minor = cpu_to_le16(4); 816 pfn_sb->end_trunc = cpu_to_le32(end_trunc); 817 pfn_sb->align = cpu_to_le32(nd_pfn->align); 818 pfn_sb->page_struct_size = cpu_to_le16(MAX_STRUCT_PAGE_SIZE); 819 pfn_sb->page_size = cpu_to_le32(PAGE_SIZE); 820 checksum = nd_sb_checksum((struct nd_gen_sb *) pfn_sb); 821 pfn_sb->checksum = cpu_to_le64(checksum); 822 823 rc = nd_pfn_clear_memmap_errors(nd_pfn); 824 if (rc) 825 return rc; 826 827 return nvdimm_write_bytes(ndns, SZ_4K, pfn_sb, sizeof(*pfn_sb), 0); 828 } 829 830 /* 831 * Determine the effective resource range and vmem_altmap from an nd_pfn 832 * instance. 833 */ 834 int nvdimm_setup_pfn(struct nd_pfn *nd_pfn, struct dev_pagemap *pgmap) 835 { 836 int rc; 837 838 if (!nd_pfn->uuid || !nd_pfn->ndns) 839 return -ENODEV; 840 841 rc = nd_pfn_init(nd_pfn); 842 if (rc) 843 return rc; 844 845 /* we need a valid pfn_sb before we can init a dev_pagemap */ 846 return __nvdimm_setup_pfn(nd_pfn, pgmap); 847 } 848 EXPORT_SYMBOL_GPL(nvdimm_setup_pfn); 849