drivers/nvdimm/label.c

   1 /*
   2  * Copyright(c) 2013-2015 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/device.h>
  14 #include <linux/ndctl.h>
  15 #include <linux/uuid.h>
  16 #include <linux/slab.h>
  17 #include <linux/io.h>
  18 #include <linux/nd.h>
  19 #include "nd-core.h"
  20 #include "label.h"
  21 #include "nd.h"
  22
  23 static guid_t nvdimm_btt_guid;
  24 static guid_t nvdimm_btt2_guid;
  25 static guid_t nvdimm_pfn_guid;
  26 static guid_t nvdimm_dax_guid;
  27
  28 static u32 best_seq(u32 a, u32 b)
  29 {
  30         a &= NSINDEX_SEQ_MASK;
  31         b &= NSINDEX_SEQ_MASK;
  32
  33         if (a == 0 || a == b)
  34                 return b;
  35         else if (b == 0)
  36                 return a;
  37         else if (nd_inc_seq(a) == b)
  38                 return b;
  39         else
  40                 return a;
  41 }
  42
  43 unsigned sizeof_namespace_label(struct nvdimm_drvdata *ndd)
  44 {
  45         return ndd->nslabel_size;
  46 }
  47
  48 static size_t __sizeof_namespace_index(u32 nslot)
  49 {
  50         return ALIGN(sizeof(struct nd_namespace_index) + DIV_ROUND_UP(nslot, 8),
  51                         NSINDEX_ALIGN);
  52 }
  53
  54 static int __nvdimm_num_label_slots(struct nvdimm_drvdata *ndd,
  55                 size_t index_size)
  56 {
  57         return (ndd->nsarea.config_size - index_size * 2) /
  58                         sizeof_namespace_label(ndd);
  59 }
  60
  61 int nvdimm_num_label_slots(struct nvdimm_drvdata *ndd)
  62 {
  63         u32 tmp_nslot, n;
  64
  65         tmp_nslot = ndd->nsarea.config_size / sizeof_namespace_label(ndd);
  66         n = __sizeof_namespace_index(tmp_nslot) / NSINDEX_ALIGN;
  67
  68         return __nvdimm_num_label_slots(ndd, NSINDEX_ALIGN * n);
  69 }
  70
  71 size_t sizeof_namespace_index(struct nvdimm_drvdata *ndd)
  72 {
  73         u32 nslot, space, size;
  74
  75         /*
  76          * Per UEFI 2.7, the minimum size of the Label Storage Area is large
  77          * enough to hold 2 index blocks and 2 labels.  The minimum index
  78          * block size is 256 bytes, and the minimum label size is 256 bytes.
  79          */
  80         nslot = nvdimm_num_label_slots(ndd);
  81         space = ndd->nsarea.config_size - nslot * sizeof_namespace_label(ndd);
  82         size = __sizeof_namespace_index(nslot) * 2;
  83         if (size <= space && nslot >= 2)
  84                 return size / 2;
  85
  86         dev_err(ndd->dev, "label area (%d) too small to host (%d byte) labels\n",
  87                         ndd->nsarea.config_size, sizeof_namespace_label(ndd));
  88         return 0;
  89 }
  90
  91 static int __nd_label_validate(struct nvdimm_drvdata *ndd)
  92 {
  93         /*
  94          * On media label format consists of two index blocks followed
  95          * by an array of labels.  None of these structures are ever
  96          * updated in place.  A sequence number tracks the current
  97          * active index and the next one to write, while labels are
  98          * written to free slots.
  99          *
 100          *     +------------+
 101          *     |            |
 102          *     |  nsindex0  |
 103          *     |            |
 104          *     +------------+
 105          *     |            |
 106          *     |  nsindex1  |
 107          *     |            |
 108          *     +------------+
 109          *     |   label0   |
 110          *     +------------+
 111          *     |   label1   |
 112          *     +------------+
 113          *     |            |
 114          *      ....nslot...
 115          *     |            |
 116          *     +------------+
 117          *     |   labelN   |
 118          *     +------------+
 119          */
 120         struct nd_namespace_index *nsindex[] = {
 121                 to_namespace_index(ndd, 0),
 122                 to_namespace_index(ndd, 1),
 123         };
 124         const int num_index = ARRAY_SIZE(nsindex);
 125         struct device *dev = ndd->dev;
 126         bool valid[2] = { 0 };
 127         int i, num_valid = 0;
 128         u32 seq;
 129
 130         for (i = 0; i < num_index; i++) {
 131                 u32 nslot;
 132                 u8 sig[NSINDEX_SIG_LEN];
 133                 u64 sum_save, sum, size;
 134                 unsigned int version, labelsize;
 135
 136                 memcpy(sig, nsindex[i]->sig, NSINDEX_SIG_LEN);
 137                 if (memcmp(sig, NSINDEX_SIGNATURE, NSINDEX_SIG_LEN) != 0) {
 138                         dev_dbg(dev, "nsindex%d signature invalid\n", i);
 139                         continue;
 140                 }
 141
 142                 /* label sizes larger than 128 arrived with v1.2 */
 143                 version = __le16_to_cpu(nsindex[i]->major) * 100
 144                         + __le16_to_cpu(nsindex[i]->minor);
 145                 if (version >= 102)
 146                         labelsize = 1 << (7 + nsindex[i]->labelsize);
 147                 else
 148                         labelsize = 128;
 149
 150                 if (labelsize != sizeof_namespace_label(ndd)) {
 151                         dev_dbg(dev, "nsindex%d labelsize %d invalid\n",
 152                                         i, nsindex[i]->labelsize);
 153                         continue;
 154                 }
 155
 156                 sum_save = __le64_to_cpu(nsindex[i]->checksum);
 157                 nsindex[i]->checksum = __cpu_to_le64(0);
 158                 sum = nd_fletcher64(nsindex[i], sizeof_namespace_index(ndd), 1);
 159                 nsindex[i]->checksum = __cpu_to_le64(sum_save);
 160                 if (sum != sum_save) {
 161                         dev_dbg(dev, "nsindex%d checksum invalid\n", i);
 162                         continue;
 163                 }
 164
 165                 seq = __le32_to_cpu(nsindex[i]->seq);
 166                 if ((seq & NSINDEX_SEQ_MASK) == 0) {
 167                         dev_dbg(dev, "nsindex%d sequence: %#x invalid\n", i, seq);
 168                         continue;
 169                 }
 170
 171                 /* sanity check the index against expected values */
 172                 if (__le64_to_cpu(nsindex[i]->myoff)
 173                                 != i * sizeof_namespace_index(ndd)) {
 174                         dev_dbg(dev, "nsindex%d myoff: %#llx invalid\n",
 175                                         i, (unsigned long long)
 176                                         __le64_to_cpu(nsindex[i]->myoff));
 177                         continue;
 178                 }
 179                 if (__le64_to_cpu(nsindex[i]->otheroff)
 180                                 != (!i) * sizeof_namespace_index(ndd)) {
 181                         dev_dbg(dev, "nsindex%d otheroff: %#llx invalid\n",
 182                                         i, (unsigned long long)
 183                                         __le64_to_cpu(nsindex[i]->otheroff));
 184                         continue;
 185                 }
 186
 187                 size = __le64_to_cpu(nsindex[i]->mysize);
 188                 if (size > sizeof_namespace_index(ndd)
 189                                 || size < sizeof(struct nd_namespace_index)) {
 190                         dev_dbg(dev, "nsindex%d mysize: %#llx invalid\n", i, size);
 191                         continue;
 192                 }
 193
 194                 nslot = __le32_to_cpu(nsindex[i]->nslot);
 195                 if (nslot * sizeof_namespace_label(ndd)
 196                                 + 2 * sizeof_namespace_index(ndd)
 197                                 > ndd->nsarea.config_size) {
 198                         dev_dbg(dev, "nsindex%d nslot: %u invalid, config_size: %#x\n",
 199                                         i, nslot, ndd->nsarea.config_size);
 200                         continue;
 201                 }
 202                 valid[i] = true;
 203                 num_valid++;
 204         }
 205
 206         switch (num_valid) {
 207         case 0:
 208                 break;
 209         case 1:
 210                 for (i = 0; i < num_index; i++)
 211                         if (valid[i])
 212                                 return i;
 213                 /* can't have num_valid > 0 but valid[] = { false, false } */
 214                 WARN_ON(1);
 215                 break;
 216         default:
 217                 /* pick the best index... */
 218                 seq = best_seq(__le32_to_cpu(nsindex[0]->seq),
 219                                 __le32_to_cpu(nsindex[1]->seq));
 220                 if (seq == (__le32_to_cpu(nsindex[1]->seq) & NSINDEX_SEQ_MASK))
 221                         return 1;
 222                 else
 223                         return 0;
 224                 break;
 225         }
 226
 227         return -1;
 228 }
 229
 230 int nd_label_validate(struct nvdimm_drvdata *ndd)
 231 {
 232         /*
 233          * In order to probe for and validate namespace index blocks we
 234          * need to know the size of the labels, and we can't trust the
 235          * size of the labels until we validate the index blocks.
 236          * Resolve this dependency loop by probing for known label
 237          * sizes, but default to v1.2 256-byte namespace labels if
 238          * discovery fails.
 239          */
 240         int label_size[] = { 128, 256 };
 241         int i, rc;
 242
 243         for (i = 0; i < ARRAY_SIZE(label_size); i++) {
 244                 ndd->nslabel_size = label_size[i];
 245                 rc = __nd_label_validate(ndd);
 246                 if (rc >= 0)
 247                         return rc;
 248         }
 249
 250         return -1;
 251 }
 252
 253 void nd_label_copy(struct nvdimm_drvdata *ndd, struct nd_namespace_index *dst,
 254                 struct nd_namespace_index *src)
 255 {
 256         if (dst && src)
 257                 /* pass */;
 258         else
 259                 return;
 260
 261         memcpy(dst, src, sizeof_namespace_index(ndd));
 262 }
 263
 264 static struct nd_namespace_label *nd_label_base(struct nvdimm_drvdata *ndd)
 265 {
 266         void *base = to_namespace_index(ndd, 0);
 267
 268         return base + 2 * sizeof_namespace_index(ndd);
 269 }
 270
 271 static int to_slot(struct nvdimm_drvdata *ndd,
 272                 struct nd_namespace_label *nd_label)
 273 {
 274         unsigned long label, base;
 275
 276         label = (unsigned long) nd_label;
 277         base = (unsigned long) nd_label_base(ndd);
 278
 279         return (label - base) / sizeof_namespace_label(ndd);
 280 }
 281
 282 static struct nd_namespace_label *to_label(struct nvdimm_drvdata *ndd, int slot)
 283 {
 284         unsigned long label, base;
 285
 286         base = (unsigned long) nd_label_base(ndd);
 287         label = base + sizeof_namespace_label(ndd) * slot;
 288
 289         return (struct nd_namespace_label *) label;
 290 }
 291
 292 #define for_each_clear_bit_le(bit, addr, size) \
 293         for ((bit) = find_next_zero_bit_le((addr), (size), 0);  \
 294              (bit) < (size);                                    \
 295              (bit) = find_next_zero_bit_le((addr), (size), (bit) + 1))
 296
 297 /**
 298  * preamble_index - common variable initialization for nd_label_* routines
 299  * @ndd: dimm container for the relevant label set
 300  * @idx: namespace_index index
 301  * @nsindex_out: on return set to the currently active namespace index
 302  * @free: on return set to the free label bitmap in the index
 303  * @nslot: on return set to the number of slots in the label space
 304  */
 305 static bool preamble_index(struct nvdimm_drvdata *ndd, int idx,
 306                 struct nd_namespace_index **nsindex_out,
 307                 unsigned long **free, u32 *nslot)
 308 {
 309         struct nd_namespace_index *nsindex;
 310
 311         nsindex = to_namespace_index(ndd, idx);
 312         if (nsindex == NULL)
 313                 return false;
 314
 315         *free = (unsigned long *) nsindex->free;
 316         *nslot = __le32_to_cpu(nsindex->nslot);
 317         *nsindex_out = nsindex;
 318
 319         return true;
 320 }
 321
 322 char *nd_label_gen_id(struct nd_label_id *label_id, u8 *uuid, u32 flags)
 323 {
 324         if (!label_id || !uuid)
 325                 return NULL;
 326         snprintf(label_id->id, ND_LABEL_ID_SIZE, "%s-%pUb",
 327                         flags & NSLABEL_FLAG_LOCAL ? "blk" : "pmem", uuid);
 328         return label_id->id;
 329 }
 330
 331 static bool preamble_current(struct nvdimm_drvdata *ndd,
 332                 struct nd_namespace_index **nsindex,
 333                 unsigned long **free, u32 *nslot)
 334 {
 335         return preamble_index(ndd, ndd->ns_current, nsindex,
 336                         free, nslot);
 337 }
 338
 339 static bool preamble_next(struct nvdimm_drvdata *ndd,
 340                 struct nd_namespace_index **nsindex,
 341                 unsigned long **free, u32 *nslot)
 342 {
 343         return preamble_index(ndd, ndd->ns_next, nsindex,
 344                         free, nslot);
 345 }
 346
 347 static bool slot_valid(struct nvdimm_drvdata *ndd,
 348                 struct nd_namespace_label *nd_label, u32 slot)
 349 {
 350         /* check that we are written where we expect to be written */
 351         if (slot != __le32_to_cpu(nd_label->slot))
 352                 return false;
 353
 354         /* check that DPA allocations are page aligned */
 355         if ((__le64_to_cpu(nd_label->dpa)
 356                                 | __le64_to_cpu(nd_label->rawsize)) % SZ_4K)
 357                 return false;
 358
 359         /* check checksum */
 360         if (namespace_label_has(ndd, checksum)) {
 361                 u64 sum, sum_save;
 362
 363                 sum_save = __le64_to_cpu(nd_label->checksum);
 364                 nd_label->checksum = __cpu_to_le64(0);
 365                 sum = nd_fletcher64(nd_label, sizeof_namespace_label(ndd), 1);
 366                 nd_label->checksum = __cpu_to_le64(sum_save);
 367                 if (sum != sum_save) {
 368                         dev_dbg(ndd->dev, "fail checksum. slot: %d expect: %#llx\n",
 369                                 slot, sum);
 370                         return false;
 371                 }
 372         }
 373
 374         return true;
 375 }
 376
 377 int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd)
 378 {
 379         struct nd_namespace_index *nsindex;
 380         unsigned long *free;
 381         u32 nslot, slot;
 382
 383         if (!preamble_current(ndd, &nsindex, &free, &nslot))
 384                 return 0; /* no label, nothing to reserve */
 385
 386         for_each_clear_bit_le(slot, free, nslot) {
 387                 struct nd_namespace_label *nd_label;
 388                 struct nd_region *nd_region = NULL;
 389                 u8 label_uuid[NSLABEL_UUID_LEN];
 390                 struct nd_label_id label_id;
 391                 struct resource *res;
 392                 u32 flags;
 393
 394                 nd_label = to_label(ndd, slot);
 395
 396                 if (!slot_valid(ndd, nd_label, slot))
 397                         continue;
 398
 399                 memcpy(label_uuid, nd_label->uuid, NSLABEL_UUID_LEN);
 400                 flags = __le32_to_cpu(nd_label->flags);
 401                 nd_label_gen_id(&label_id, label_uuid, flags);
 402                 res = nvdimm_allocate_dpa(ndd, &label_id,
 403                                 __le64_to_cpu(nd_label->dpa),
 404                                 __le64_to_cpu(nd_label->rawsize));
 405                 nd_dbg_dpa(nd_region, ndd, res, "reserve\n");
 406                 if (!res)
 407                         return -EBUSY;
 408         }
 409
 410         return 0;
 411 }
 412
 413 int nd_label_active_count(struct nvdimm_drvdata *ndd)
 414 {
 415         struct nd_namespace_index *nsindex;
 416         unsigned long *free;
 417         u32 nslot, slot;
 418         int count = 0;
 419
 420         if (!preamble_current(ndd, &nsindex, &free, &nslot))
 421                 return 0;
 422
 423         for_each_clear_bit_le(slot, free, nslot) {
 424                 struct nd_namespace_label *nd_label;
 425
 426                 nd_label = to_label(ndd, slot);
 427
 428                 if (!slot_valid(ndd, nd_label, slot)) {
 429                         u32 label_slot = __le32_to_cpu(nd_label->slot);
 430                         u64 size = __le64_to_cpu(nd_label->rawsize);
 431                         u64 dpa = __le64_to_cpu(nd_label->dpa);
 432
 433                         dev_dbg(ndd->dev,
 434                                 "slot%d invalid slot: %d dpa: %llx size: %llx\n",
 435                                         slot, label_slot, dpa, size);
 436                         continue;
 437                 }
 438                 count++;
 439         }
 440         return count;
 441 }
 442
 443 struct nd_namespace_label *nd_label_active(struct nvdimm_drvdata *ndd, int n)
 444 {
 445         struct nd_namespace_index *nsindex;
 446         unsigned long *free;
 447         u32 nslot, slot;
 448
 449         if (!preamble_current(ndd, &nsindex, &free, &nslot))
 450                 return NULL;
 451
 452         for_each_clear_bit_le(slot, free, nslot) {
 453                 struct nd_namespace_label *nd_label;
 454
 455                 nd_label = to_label(ndd, slot);
 456                 if (!slot_valid(ndd, nd_label, slot))
 457                         continue;
 458
 459                 if (n-- == 0)
 460                         return to_label(ndd, slot);
 461         }
 462
 463         return NULL;
 464 }
 465
 466 u32 nd_label_alloc_slot(struct nvdimm_drvdata *ndd)
 467 {
 468         struct nd_namespace_index *nsindex;
 469         unsigned long *free;
 470         u32 nslot, slot;
 471
 472         if (!preamble_next(ndd, &nsindex, &free, &nslot))
 473                 return UINT_MAX;
 474
 475         WARN_ON(!is_nvdimm_bus_locked(ndd->dev));
 476
 477         slot = find_next_bit_le(free, nslot, 0);
 478         if (slot == nslot)
 479                 return UINT_MAX;
 480
 481         clear_bit_le(slot, free);
 482
 483         return slot;
 484 }
 485
 486 bool nd_label_free_slot(struct nvdimm_drvdata *ndd, u32 slot)
 487 {
 488         struct nd_namespace_index *nsindex;
 489         unsigned long *free;
 490         u32 nslot;
 491
 492         if (!preamble_next(ndd, &nsindex, &free, &nslot))
 493                 return false;
 494
 495         WARN_ON(!is_nvdimm_bus_locked(ndd->dev));
 496
 497         if (slot < nslot)
 498                 return !test_and_set_bit_le(slot, free);
 499         return false;
 500 }
 501
 502 u32 nd_label_nfree(struct nvdimm_drvdata *ndd)
 503 {
 504         struct nd_namespace_index *nsindex;
 505         unsigned long *free;
 506         u32 nslot;
 507
 508         WARN_ON(!is_nvdimm_bus_locked(ndd->dev));
 509
 510         if (!preamble_next(ndd, &nsindex, &free, &nslot))
 511                 return nvdimm_num_label_slots(ndd);
 512
 513         return bitmap_weight(free, nslot);
 514 }
 515
 516 static int nd_label_write_index(struct nvdimm_drvdata *ndd, int index, u32 seq,
 517                 unsigned long flags)
 518 {
 519         struct nd_namespace_index *nsindex;
 520         unsigned long offset;
 521         u64 checksum;
 522         u32 nslot;
 523         int rc;
 524
 525         nsindex = to_namespace_index(ndd, index);
 526         if (flags & ND_NSINDEX_INIT)
 527                 nslot = nvdimm_num_label_slots(ndd);
 528         else
 529                 nslot = __le32_to_cpu(nsindex->nslot);
 530
 531         memcpy(nsindex->sig, NSINDEX_SIGNATURE, NSINDEX_SIG_LEN);
 532         memset(&nsindex->flags, 0, 3);
 533         nsindex->labelsize = sizeof_namespace_label(ndd) >> 8;
 534         nsindex->seq = __cpu_to_le32(seq);
 535         offset = (unsigned long) nsindex
 536                 - (unsigned long) to_namespace_index(ndd, 0);
 537         nsindex->myoff = __cpu_to_le64(offset);
 538         nsindex->mysize = __cpu_to_le64(sizeof_namespace_index(ndd));
 539         offset = (unsigned long) to_namespace_index(ndd,
 540                         nd_label_next_nsindex(index))
 541                 - (unsigned long) to_namespace_index(ndd, 0);
 542         nsindex->otheroff = __cpu_to_le64(offset);
 543         offset = (unsigned long) nd_label_base(ndd)
 544                 - (unsigned long) to_namespace_index(ndd, 0);
 545         nsindex->labeloff = __cpu_to_le64(offset);
 546         nsindex->nslot = __cpu_to_le32(nslot);
 547         nsindex->major = __cpu_to_le16(1);
 548         if (sizeof_namespace_label(ndd) < 256)
 549                 nsindex->minor = __cpu_to_le16(1);
 550         else
 551                 nsindex->minor = __cpu_to_le16(2);
 552         nsindex->checksum = __cpu_to_le64(0);
 553         if (flags & ND_NSINDEX_INIT) {
 554                 unsigned long *free = (unsigned long *) nsindex->free;
 555                 u32 nfree = ALIGN(nslot, BITS_PER_LONG);
 556                 int last_bits, i;
 557
 558                 memset(nsindex->free, 0xff, nfree / 8);
 559                 for (i = 0, last_bits = nfree - nslot; i < last_bits; i++)
 560                         clear_bit_le(nslot + i, free);
 561         }
 562         checksum = nd_fletcher64(nsindex, sizeof_namespace_index(ndd), 1);
 563         nsindex->checksum = __cpu_to_le64(checksum);
 564         rc = nvdimm_set_config_data(ndd, __le64_to_cpu(nsindex->myoff),
 565                         nsindex, sizeof_namespace_index(ndd));
 566         if (rc < 0)
 567                 return rc;
 568
 569         if (flags & ND_NSINDEX_INIT)
 570                 return 0;
 571
 572         /* copy the index we just wrote to the new 'next' */
 573         WARN_ON(index != ndd->ns_next);
 574         nd_label_copy(ndd, to_current_namespace_index(ndd), nsindex);
 575         ndd->ns_current = nd_label_next_nsindex(ndd->ns_current);
 576         ndd->ns_next = nd_label_next_nsindex(ndd->ns_next);
 577         WARN_ON(ndd->ns_current == ndd->ns_next);
 578
 579         return 0;
 580 }
 581
 582 static unsigned long nd_label_offset(struct nvdimm_drvdata *ndd,
 583                 struct nd_namespace_label *nd_label)
 584 {
 585         return (unsigned long) nd_label
 586                 - (unsigned long) to_namespace_index(ndd, 0);
 587 }
 588
 589 enum nvdimm_claim_class to_nvdimm_cclass(guid_t *guid)
 590 {
 591         if (guid_equal(guid, &nvdimm_btt_guid))
 592                 return NVDIMM_CCLASS_BTT;
 593         else if (guid_equal(guid, &nvdimm_btt2_guid))
 594                 return NVDIMM_CCLASS_BTT2;
 595         else if (guid_equal(guid, &nvdimm_pfn_guid))
 596                 return NVDIMM_CCLASS_PFN;
 597         else if (guid_equal(guid, &nvdimm_dax_guid))
 598                 return NVDIMM_CCLASS_DAX;
 599         else if (guid_equal(guid, &guid_null))
 600                 return NVDIMM_CCLASS_NONE;
 601
 602         return NVDIMM_CCLASS_UNKNOWN;
 603 }
 604
 605 static const guid_t *to_abstraction_guid(enum nvdimm_claim_class claim_class,
 606         guid_t *target)
 607 {
 608         if (claim_class == NVDIMM_CCLASS_BTT)
 609                 return &nvdimm_btt_guid;
 610         else if (claim_class == NVDIMM_CCLASS_BTT2)
 611                 return &nvdimm_btt2_guid;
 612         else if (claim_class == NVDIMM_CCLASS_PFN)
 613                 return &nvdimm_pfn_guid;
 614         else if (claim_class == NVDIMM_CCLASS_DAX)
 615                 return &nvdimm_dax_guid;
 616         else if (claim_class == NVDIMM_CCLASS_UNKNOWN) {
 617                 /*
 618                  * If we're modifying a namespace for which we don't
 619                  * know the claim_class, don't touch the existing guid.
 620                  */
 621                 return target;
 622         } else
 623                 return &guid_null;
 624 }
 625
 626 static int __pmem_label_update(struct nd_region *nd_region,
 627                 struct nd_mapping *nd_mapping, struct nd_namespace_pmem *nspm,
 628                 int pos)
 629 {
 630         struct nd_namespace_common *ndns = &nspm->nsio.common;
 631         struct nd_interleave_set *nd_set = nd_region->nd_set;
 632         struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
 633         struct nd_label_ent *label_ent, *victim = NULL;
 634         struct nd_namespace_label *nd_label;
 635         struct nd_namespace_index *nsindex;
 636         struct nd_label_id label_id;
 637         struct resource *res;
 638         unsigned long *free;
 639         u32 nslot, slot;
 640         size_t offset;
 641         u64 cookie;
 642         int rc;
 643
 644         if (!preamble_next(ndd, &nsindex, &free, &nslot))
 645                 return -ENXIO;
 646
 647         cookie = nd_region_interleave_set_cookie(nd_region, nsindex);
 648         nd_label_gen_id(&label_id, nspm->uuid, 0);
 649         for_each_dpa_resource(ndd, res)
 650                 if (strcmp(res->name, label_id.id) == 0)
 651                         break;
 652
 653         if (!res) {
 654                 WARN_ON_ONCE(1);
 655                 return -ENXIO;
 656         }
 657
 658         /* allocate and write the label to the staging (next) index */
 659         slot = nd_label_alloc_slot(ndd);
 660         if (slot == UINT_MAX)
 661                 return -ENXIO;
 662         dev_dbg(ndd->dev, "allocated: %d\n", slot);
 663
 664         nd_label = to_label(ndd, slot);
 665         memset(nd_label, 0, sizeof_namespace_label(ndd));
 666         memcpy(nd_label->uuid, nspm->uuid, NSLABEL_UUID_LEN);
 667         if (nspm->alt_name)
 668                 memcpy(nd_label->name, nspm->alt_name, NSLABEL_NAME_LEN);
 669         nd_label->flags = __cpu_to_le32(NSLABEL_FLAG_UPDATING);
 670         nd_label->nlabel = __cpu_to_le16(nd_region->ndr_mappings);
 671         nd_label->position = __cpu_to_le16(pos);
 672         nd_label->isetcookie = __cpu_to_le64(cookie);
 673         nd_label->rawsize = __cpu_to_le64(resource_size(res));
 674         nd_label->lbasize = __cpu_to_le64(nspm->lbasize);
 675         nd_label->dpa = __cpu_to_le64(res->start);
 676         nd_label->slot = __cpu_to_le32(slot);
 677         if (namespace_label_has(ndd, type_guid))
 678                 guid_copy(&nd_label->type_guid, &nd_set->type_guid);
 679         if (namespace_label_has(ndd, abstraction_guid))
 680                 guid_copy(&nd_label->abstraction_guid,
 681                                 to_abstraction_guid(ndns->claim_class,
 682                                         &nd_label->abstraction_guid));
 683         if (namespace_label_has(ndd, checksum)) {
 684                 u64 sum;
 685
 686                 nd_label->checksum = __cpu_to_le64(0);
 687                 sum = nd_fletcher64(nd_label, sizeof_namespace_label(ndd), 1);
 688                 nd_label->checksum = __cpu_to_le64(sum);
 689         }
 690         nd_dbg_dpa(nd_region, ndd, res, "\n");
 691
 692         /* update label */
 693         offset = nd_label_offset(ndd, nd_label);
 694         rc = nvdimm_set_config_data(ndd, offset, nd_label,
 695                         sizeof_namespace_label(ndd));
 696         if (rc < 0)
 697                 return rc;
 698
 699         /* Garbage collect the previous label */
 700         mutex_lock(&nd_mapping->lock);
 701         list_for_each_entry(label_ent, &nd_mapping->labels, list) {
 702                 if (!label_ent->label)
 703                         continue;
 704                 if (memcmp(nspm->uuid, label_ent->label->uuid,
 705                                         NSLABEL_UUID_LEN) != 0)
 706                         continue;
 707                 victim = label_ent;
 708                 list_move_tail(&victim->list, &nd_mapping->labels);
 709                 break;
 710         }
 711         if (victim) {
 712                 dev_dbg(ndd->dev, "free: %d\n", slot);
 713                 slot = to_slot(ndd, victim->label);
 714                 nd_label_free_slot(ndd, slot);
 715                 victim->label = NULL;
 716         }
 717
 718         /* update index */
 719         rc = nd_label_write_index(ndd, ndd->ns_next,
 720                         nd_inc_seq(__le32_to_cpu(nsindex->seq)), 0);
 721         if (rc == 0) {
 722                 list_for_each_entry(label_ent, &nd_mapping->labels, list)
 723                         if (!label_ent->label) {
 724                                 label_ent->label = nd_label;
 725                                 nd_label = NULL;
 726                                 break;
 727                         }
 728                 dev_WARN_ONCE(&nspm->nsio.common.dev, nd_label,
 729                                 "failed to track label: %d\n",
 730                                 to_slot(ndd, nd_label));
 731                 if (nd_label)
 732                         rc = -ENXIO;
 733         }
 734         mutex_unlock(&nd_mapping->lock);
 735
 736         return rc;
 737 }
 738
 739 static bool is_old_resource(struct resource *res, struct resource **list, int n)
 740 {
 741         int i;
 742
 743         if (res->flags & DPA_RESOURCE_ADJUSTED)
 744                 return false;
 745         for (i = 0; i < n; i++)
 746                 if (res == list[i])
 747                         return true;
 748         return false;
 749 }
 750
 751 static struct resource *to_resource(struct nvdimm_drvdata *ndd,
 752                 struct nd_namespace_label *nd_label)
 753 {
 754         struct resource *res;
 755
 756         for_each_dpa_resource(ndd, res) {
 757                 if (res->start != __le64_to_cpu(nd_label->dpa))
 758                         continue;
 759                 if (resource_size(res) != __le64_to_cpu(nd_label->rawsize))
 760                         continue;
 761                 return res;
 762         }
 763
 764         return NULL;
 765 }
 766
 767 /*
 768  * 1/ Account all the labels that can be freed after this update
 769  * 2/ Allocate and write the label to the staging (next) index
 770  * 3/ Record the resources in the namespace device
 771  */
 772 static int __blk_label_update(struct nd_region *nd_region,
 773                 struct nd_mapping *nd_mapping, struct nd_namespace_blk *nsblk,
 774                 int num_labels)
 775 {
 776         int i, alloc, victims, nfree, old_num_resources, nlabel, rc = -ENXIO;
 777         struct nd_interleave_set *nd_set = nd_region->nd_set;
 778         struct nd_namespace_common *ndns = &nsblk->common;
 779         struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
 780         struct nd_namespace_label *nd_label;
 781         struct nd_label_ent *label_ent, *e;
 782         struct nd_namespace_index *nsindex;
 783         unsigned long *free, *victim_map = NULL;
 784         struct resource *res, **old_res_list;
 785         struct nd_label_id label_id;
 786         u8 uuid[NSLABEL_UUID_LEN];
 787         int min_dpa_idx = 0;
 788         LIST_HEAD(list);
 789         u32 nslot, slot;
 790
 791         if (!preamble_next(ndd, &nsindex, &free, &nslot))
 792                 return -ENXIO;
 793
 794         old_res_list = nsblk->res;
 795         nfree = nd_label_nfree(ndd);
 796         old_num_resources = nsblk->num_resources;
 797         nd_label_gen_id(&label_id, nsblk->uuid, NSLABEL_FLAG_LOCAL);
 798
 799         /*
 800          * We need to loop over the old resources a few times, which seems a
 801          * bit inefficient, but we need to know that we have the label
 802          * space before we start mutating the tracking structures.
 803          * Otherwise the recovery method of last resort for userspace is
 804          * disable and re-enable the parent region.
 805          */
 806         alloc = 0;
 807         for_each_dpa_resource(ndd, res) {
 808                 if (strcmp(res->name, label_id.id) != 0)
 809                         continue;
 810                 if (!is_old_resource(res, old_res_list, old_num_resources))
 811                         alloc++;
 812         }
 813
 814         victims = 0;
 815         if (old_num_resources) {
 816                 /* convert old local-label-map to dimm-slot victim-map */
 817                 victim_map = kcalloc(BITS_TO_LONGS(nslot), sizeof(long),
 818                                 GFP_KERNEL);
 819                 if (!victim_map)
 820                         return -ENOMEM;
 821
 822                 /* mark unused labels for garbage collection */
 823                 for_each_clear_bit_le(slot, free, nslot) {
 824                         nd_label = to_label(ndd, slot);
 825                         memcpy(uuid, nd_label->uuid, NSLABEL_UUID_LEN);
 826                         if (memcmp(uuid, nsblk->uuid, NSLABEL_UUID_LEN) != 0)
 827                                 continue;
 828                         res = to_resource(ndd, nd_label);
 829                         if (res && is_old_resource(res, old_res_list,
 830                                                 old_num_resources))
 831                                 continue;
 832                         slot = to_slot(ndd, nd_label);
 833                         set_bit(slot, victim_map);
 834                         victims++;
 835                 }
 836         }
 837
 838         /* don't allow updates that consume the last label */
 839         if (nfree - alloc < 0 || nfree - alloc + victims < 1) {
 840                 dev_info(&nsblk->common.dev, "insufficient label space\n");
 841                 kfree(victim_map);
 842                 return -ENOSPC;
 843         }
 844         /* from here on we need to abort on error */
 845
 846
 847         /* assign all resources to the namespace before writing the labels */
 848         nsblk->res = NULL;
 849         nsblk->num_resources = 0;
 850         for_each_dpa_resource(ndd, res) {
 851                 if (strcmp(res->name, label_id.id) != 0)
 852                         continue;
 853                 if (!nsblk_add_resource(nd_region, ndd, nsblk, res->start)) {
 854                         rc = -ENOMEM;
 855                         goto abort;
 856                 }
 857         }
 858
 859         /*
 860          * Find the resource associated with the first label in the set
 861          * per the v1.2 namespace specification.
 862          */
 863         for (i = 0; i < nsblk->num_resources; i++) {
 864                 struct resource *min = nsblk->res[min_dpa_idx];
 865
 866                 res = nsblk->res[i];
 867                 if (res->start < min->start)
 868                         min_dpa_idx = i;
 869         }
 870
 871         for (i = 0; i < nsblk->num_resources; i++) {
 872                 size_t offset;
 873
 874                 res = nsblk->res[i];
 875                 if (is_old_resource(res, old_res_list, old_num_resources))
 876                         continue; /* carry-over */
 877                 slot = nd_label_alloc_slot(ndd);
 878                 if (slot == UINT_MAX)
 879                         goto abort;
 880                 dev_dbg(ndd->dev, "allocated: %d\n", slot);
 881
 882                 nd_label = to_label(ndd, slot);
 883                 memset(nd_label, 0, sizeof_namespace_label(ndd));
 884                 memcpy(nd_label->uuid, nsblk->uuid, NSLABEL_UUID_LEN);
 885                 if (nsblk->alt_name)
 886                         memcpy(nd_label->name, nsblk->alt_name,
 887                                         NSLABEL_NAME_LEN);
 888                 nd_label->flags = __cpu_to_le32(NSLABEL_FLAG_LOCAL);
 889
 890                 /*
 891                  * Use the presence of the type_guid as a flag to
 892                  * determine isetcookie usage and nlabel + position
 893                  * policy for blk-aperture namespaces.
 894                  */
 895                 if (namespace_label_has(ndd, type_guid)) {
 896                         if (i == min_dpa_idx) {
 897                                 nd_label->nlabel = __cpu_to_le16(nsblk->num_resources);
 898                                 nd_label->position = __cpu_to_le16(0);
 899                         } else {
 900                                 nd_label->nlabel = __cpu_to_le16(0xffff);
 901                                 nd_label->position = __cpu_to_le16(0xffff);
 902                         }
 903                         nd_label->isetcookie = __cpu_to_le64(nd_set->cookie2);
 904                 } else {
 905                         nd_label->nlabel = __cpu_to_le16(0); /* N/A */
 906                         nd_label->position = __cpu_to_le16(0); /* N/A */
 907                         nd_label->isetcookie = __cpu_to_le64(0); /* N/A */
 908                 }
 909
 910                 nd_label->dpa = __cpu_to_le64(res->start);
 911                 nd_label->rawsize = __cpu_to_le64(resource_size(res));
 912                 nd_label->lbasize = __cpu_to_le64(nsblk->lbasize);
 913                 nd_label->slot = __cpu_to_le32(slot);
 914                 if (namespace_label_has(ndd, type_guid))
 915                         guid_copy(&nd_label->type_guid, &nd_set->type_guid);
 916                 if (namespace_label_has(ndd, abstraction_guid))
 917                         guid_copy(&nd_label->abstraction_guid,
 918                                         to_abstraction_guid(ndns->claim_class,
 919                                                 &nd_label->abstraction_guid));
 920
 921                 if (namespace_label_has(ndd, checksum)) {
 922                         u64 sum;
 923
 924                         nd_label->checksum = __cpu_to_le64(0);
 925                         sum = nd_fletcher64(nd_label,
 926                                         sizeof_namespace_label(ndd), 1);
 927                         nd_label->checksum = __cpu_to_le64(sum);
 928                 }
 929
 930                 /* update label */
 931                 offset = nd_label_offset(ndd, nd_label);
 932                 rc = nvdimm_set_config_data(ndd, offset, nd_label,
 933                                 sizeof_namespace_label(ndd));
 934                 if (rc < 0)
 935                         goto abort;
 936         }
 937
 938         /* free up now unused slots in the new index */
 939         for_each_set_bit(slot, victim_map, victim_map ? nslot : 0) {
 940                 dev_dbg(ndd->dev, "free: %d\n", slot);
 941                 nd_label_free_slot(ndd, slot);
 942         }
 943
 944         /* update index */
 945         rc = nd_label_write_index(ndd, ndd->ns_next,
 946                         nd_inc_seq(__le32_to_cpu(nsindex->seq)), 0);
 947         if (rc)
 948                 goto abort;
 949
 950         /*
 951          * Now that the on-dimm labels are up to date, fix up the tracking
 952          * entries in nd_mapping->labels
 953          */
 954         nlabel = 0;
 955         mutex_lock(&nd_mapping->lock);
 956         list_for_each_entry_safe(label_ent, e, &nd_mapping->labels, list) {
 957                 nd_label = label_ent->label;
 958                 if (!nd_label)
 959                         continue;
 960                 nlabel++;
 961                 memcpy(uuid, nd_label->uuid, NSLABEL_UUID_LEN);
 962                 if (memcmp(uuid, nsblk->uuid, NSLABEL_UUID_LEN) != 0)
 963                         continue;
 964                 nlabel--;
 965                 list_move(&label_ent->list, &list);
 966                 label_ent->label = NULL;
 967         }
 968         list_splice_tail_init(&list, &nd_mapping->labels);
 969         mutex_unlock(&nd_mapping->lock);
 970
 971         if (nlabel + nsblk->num_resources > num_labels) {
 972                 /*
 973                  * Bug, we can't end up with more resources than
 974                  * available labels
 975                  */
 976                 WARN_ON_ONCE(1);
 977                 rc = -ENXIO;
 978                 goto out;
 979         }
 980
 981         mutex_lock(&nd_mapping->lock);
 982         label_ent = list_first_entry_or_null(&nd_mapping->labels,
 983                         typeof(*label_ent), list);
 984         if (!label_ent) {
 985                 WARN_ON(1);
 986                 mutex_unlock(&nd_mapping->lock);
 987                 rc = -ENXIO;
 988                 goto out;
 989         }
 990         for_each_clear_bit_le(slot, free, nslot) {
 991                 nd_label = to_label(ndd, slot);
 992                 memcpy(uuid, nd_label->uuid, NSLABEL_UUID_LEN);
 993                 if (memcmp(uuid, nsblk->uuid, NSLABEL_UUID_LEN) != 0)
 994                         continue;
 995                 res = to_resource(ndd, nd_label);
 996                 res->flags &= ~DPA_RESOURCE_ADJUSTED;
 997                 dev_vdbg(&nsblk->common.dev, "assign label slot: %d\n", slot);
 998                 list_for_each_entry_from(label_ent, &nd_mapping->labels, list) {
 999                         if (label_ent->label)
1000                                 continue;
1001                         label_ent->label = nd_label;
1002                         nd_label = NULL;
1003                         break;
1004                 }
1005                 if (nd_label)
1006                         dev_WARN(&nsblk->common.dev,
1007                                         "failed to track label slot%d\n", slot);
1008         }
1009         mutex_unlock(&nd_mapping->lock);
1010
1011  out:
1012         kfree(old_res_list);
1013         kfree(victim_map);
1014         return rc;
1015
1016  abort:
1017         /*
1018          * 1/ repair the allocated label bitmap in the index
1019          * 2/ restore the resource list
1020          */
1021         nd_label_copy(ndd, nsindex, to_current_namespace_index(ndd));
1022         kfree(nsblk->res);
1023         nsblk->res = old_res_list;
1024         nsblk->num_resources = old_num_resources;
1025         old_res_list = NULL;
1026         goto out;
1027 }
1028
1029 static int init_labels(struct nd_mapping *nd_mapping, int num_labels)
1030 {
1031         int i, old_num_labels = 0;
1032         struct nd_label_ent *label_ent;
1033         struct nd_namespace_index *nsindex;
1034         struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
1035
1036         mutex_lock(&nd_mapping->lock);
1037         list_for_each_entry(label_ent, &nd_mapping->labels, list)
1038                 old_num_labels++;
1039         mutex_unlock(&nd_mapping->lock);
1040
1041         /*
1042          * We need to preserve all the old labels for the mapping so
1043          * they can be garbage collected after writing the new labels.
1044          */
1045         for (i = old_num_labels; i < num_labels; i++) {
1046                 label_ent = kzalloc(sizeof(*label_ent), GFP_KERNEL);
1047                 if (!label_ent)
1048                         return -ENOMEM;
1049                 mutex_lock(&nd_mapping->lock);
1050                 list_add_tail(&label_ent->list, &nd_mapping->labels);
1051                 mutex_unlock(&nd_mapping->lock);
1052         }
1053
1054         if (ndd->ns_current == -1 || ndd->ns_next == -1)
1055                 /* pass */;
1056         else
1057                 return max(num_labels, old_num_labels);
1058
1059         nsindex = to_namespace_index(ndd, 0);
1060         memset(nsindex, 0, ndd->nsarea.config_size);
1061         for (i = 0; i < 2; i++) {
1062                 int rc = nd_label_write_index(ndd, i, 3 - i, ND_NSINDEX_INIT);
1063
1064                 if (rc)
1065                         return rc;
1066         }
1067         ndd->ns_next = 1;
1068         ndd->ns_current = 0;
1069
1070         return max(num_labels, old_num_labels);
1071 }
1072
1073 static int del_labels(struct nd_mapping *nd_mapping, u8 *uuid)
1074 {
1075         struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
1076         struct nd_label_ent *label_ent, *e;
1077         struct nd_namespace_index *nsindex;
1078         u8 label_uuid[NSLABEL_UUID_LEN];
1079         unsigned long *free;
1080         LIST_HEAD(list);
1081         u32 nslot, slot;
1082         int active = 0;
1083
1084         if (!uuid)
1085                 return 0;
1086
1087         /* no index || no labels == nothing to delete */
1088         if (!preamble_next(ndd, &nsindex, &free, &nslot))
1089                 return 0;
1090
1091         mutex_lock(&nd_mapping->lock);
1092         list_for_each_entry_safe(label_ent, e, &nd_mapping->labels, list) {
1093                 struct nd_namespace_label *nd_label = label_ent->label;
1094
1095                 if (!nd_label)
1096                         continue;
1097                 active++;
1098                 memcpy(label_uuid, nd_label->uuid, NSLABEL_UUID_LEN);
1099                 if (memcmp(label_uuid, uuid, NSLABEL_UUID_LEN) != 0)
1100                         continue;
1101                 active--;
1102                 slot = to_slot(ndd, nd_label);
1103                 nd_label_free_slot(ndd, slot);
1104                 dev_dbg(ndd->dev, "free: %d\n", slot);
1105                 list_move_tail(&label_ent->list, &list);
1106                 label_ent->label = NULL;
1107         }
1108         list_splice_tail_init(&list, &nd_mapping->labels);
1109
1110         if (active == 0) {
1111                 nd_mapping_free_labels(nd_mapping);
1112                 dev_dbg(ndd->dev, "no more active labels\n");
1113         }
1114         mutex_unlock(&nd_mapping->lock);
1115
1116         return nd_label_write_index(ndd, ndd->ns_next,
1117                         nd_inc_seq(__le32_to_cpu(nsindex->seq)), 0);
1118 }
1119
1120 int nd_pmem_namespace_label_update(struct nd_region *nd_region,
1121                 struct nd_namespace_pmem *nspm, resource_size_t size)
1122 {
1123         int i;
1124
1125         for (i = 0; i < nd_region->ndr_mappings; i++) {
1126                 struct nd_mapping *nd_mapping = &nd_region->mapping[i];
1127                 struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
1128                 struct resource *res;
1129                 int rc, count = 0;
1130
1131                 if (size == 0) {
1132                         rc = del_labels(nd_mapping, nspm->uuid);
1133                         if (rc)
1134                                 return rc;
1135                         continue;
1136                 }
1137
1138                 for_each_dpa_resource(ndd, res)
1139                         if (strncmp(res->name, "pmem", 4) == 0)
1140                                 count++;
1141                 WARN_ON_ONCE(!count);
1142
1143                 rc = init_labels(nd_mapping, count);
1144                 if (rc < 0)
1145                         return rc;
1146
1147                 rc = __pmem_label_update(nd_region, nd_mapping, nspm, i);
1148                 if (rc)
1149                         return rc;
1150         }
1151
1152         return 0;
1153 }
1154
1155 int nd_blk_namespace_label_update(struct nd_region *nd_region,
1156                 struct nd_namespace_blk *nsblk, resource_size_t size)
1157 {
1158         struct nd_mapping *nd_mapping = &nd_region->mapping[0];
1159         struct resource *res;
1160         int count = 0;
1161
1162         if (size == 0)
1163                 return del_labels(nd_mapping, nsblk->uuid);
1164
1165         for_each_dpa_resource(to_ndd(nd_mapping), res)
1166                 count++;
1167
1168         count = init_labels(nd_mapping, count);
1169         if (count < 0)
1170                 return count;
1171
1172         return __blk_label_update(nd_region, nd_mapping, nsblk, count);
1173 }
1174
1175 int __init nd_label_init(void)
1176 {
1177         WARN_ON(guid_parse(NVDIMM_BTT_GUID, &nvdimm_btt_guid));
1178         WARN_ON(guid_parse(NVDIMM_BTT2_GUID, &nvdimm_btt2_guid));
1179         WARN_ON(guid_parse(NVDIMM_PFN_GUID, &nvdimm_pfn_guid));
1180         WARN_ON(guid_parse(NVDIMM_DAX_GUID, &nvdimm_dax_guid));
1181
1182         return 0;
1183 }