git.sur5r.net Git - u-boot/blob - drivers/mtd/ubi/fastmap.c

   1 /*
   2  * Copyright (c) 2012 Linutronix GmbH
   3  * Copyright (c) 2014 sigma star gmbh
   4  * Author: Richard Weinberger <richard@nod.at>
   5  *
   6  * SPDX-License-Identifier:     GPL-2.0+
   7  *
   8  */
   9
  10 #ifndef __UBOOT__
  11 #include <linux/crc32.h>
  12 #else
  13 #include <div64.h>
  14 #include <malloc.h>
  15 #include <ubi_uboot.h>
  16 #endif
  17
  18 #include <linux/compat.h>
  19 #include <linux/math64.h>
  20 #include "ubi.h"
  21
  22 /**
  23  * init_seen - allocate memory for used for debugging.
  24  * @ubi: UBI device description object
  25  */
  26 static inline int *init_seen(struct ubi_device *ubi)
  27 {
  28         int *ret;
  29
  30         if (!ubi_dbg_chk_fastmap(ubi))
  31                 return NULL;
  32
  33         ret = kcalloc(ubi->peb_count, sizeof(int), GFP_KERNEL);
  34         if (!ret)
  35                 return ERR_PTR(-ENOMEM);
  36
  37         return ret;
  38 }
  39
  40 /**
  41  * free_seen - free the seen logic integer array.
  42  * @seen: integer array of @ubi->peb_count size
  43  */
  44 static inline void free_seen(int *seen)
  45 {
  46         kfree(seen);
  47 }
  48
  49 /**
  50  * set_seen - mark a PEB as seen.
  51  * @ubi: UBI device description object
  52  * @pnum: The PEB to be makred as seen
  53  * @seen: integer array of @ubi->peb_count size
  54  */
  55 static inline void set_seen(struct ubi_device *ubi, int pnum, int *seen)
  56 {
  57         if (!ubi_dbg_chk_fastmap(ubi) || !seen)
  58                 return;
  59
  60         seen[pnum] = 1;
  61 }
  62
  63 /**
  64  * self_check_seen - check whether all PEB have been seen by fastmap.
  65  * @ubi: UBI device description object
  66  * @seen: integer array of @ubi->peb_count size
  67  */
  68 static int self_check_seen(struct ubi_device *ubi, int *seen)
  69 {
  70         int pnum, ret = 0;
  71
  72         if (!ubi_dbg_chk_fastmap(ubi) || !seen)
  73                 return 0;
  74
  75         for (pnum = 0; pnum < ubi->peb_count; pnum++) {
  76                 if (!seen[pnum] && ubi->lookuptbl[pnum]) {
  77                         ubi_err(ubi, "self-check failed for PEB %d, fastmap didn't see it", pnum);
  78                         ret = -EINVAL;
  79                 }
  80         }
  81
  82         return ret;
  83 }
  84
  85 /**
  86  * ubi_calc_fm_size - calculates the fastmap size in bytes for an UBI device.
  87  * @ubi: UBI device description object
  88  */
  89 size_t ubi_calc_fm_size(struct ubi_device *ubi)
  90 {
  91         size_t size;
  92
  93         size = sizeof(struct ubi_fm_sb) +
  94                 sizeof(struct ubi_fm_hdr) +
  95                 sizeof(struct ubi_fm_scan_pool) +
  96                 sizeof(struct ubi_fm_scan_pool) +
  97                 (ubi->peb_count * sizeof(struct ubi_fm_ec)) +
  98                 (sizeof(struct ubi_fm_eba) +
  99                 (ubi->peb_count * sizeof(__be32))) +
 100                 sizeof(struct ubi_fm_volhdr) * UBI_MAX_VOLUMES;
 101         return roundup(size, ubi->leb_size);
 102 }
 103
 104
 105 /**
 106  * new_fm_vhdr - allocate a new volume header for fastmap usage.
 107  * @ubi: UBI device description object
 108  * @vol_id: the VID of the new header
 109  *
 110  * Returns a new struct ubi_vid_hdr on success.
 111  * NULL indicates out of memory.
 112  */
 113 static struct ubi_vid_hdr *new_fm_vhdr(struct ubi_device *ubi, int vol_id)
 114 {
 115         struct ubi_vid_hdr *new;
 116
 117         new = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL);
 118         if (!new)
 119                 goto out;
 120
 121         new->vol_type = UBI_VID_DYNAMIC;
 122         new->vol_id = cpu_to_be32(vol_id);
 123
 124         /* UBI implementations without fastmap support have to delete the
 125          * fastmap.
 126          */
 127         new->compat = UBI_COMPAT_DELETE;
 128
 129 out:
 130         return new;
 131 }
 132
 133 /**
 134  * add_aeb - create and add a attach erase block to a given list.
 135  * @ai: UBI attach info object
 136  * @list: the target list
 137  * @pnum: PEB number of the new attach erase block
 138  * @ec: erease counter of the new LEB
 139  * @scrub: scrub this PEB after attaching
 140  *
 141  * Returns 0 on success, < 0 indicates an internal error.
 142  */
 143 static int add_aeb(struct ubi_attach_info *ai, struct list_head *list,
 144                    int pnum, int ec, int scrub)
 145 {
 146         struct ubi_ainf_peb *aeb;
 147
 148         aeb = kmem_cache_alloc(ai->aeb_slab_cache, GFP_KERNEL);
 149         if (!aeb)
 150                 return -ENOMEM;
 151
 152         aeb->pnum = pnum;
 153         aeb->ec = ec;
 154         aeb->lnum = -1;
 155         aeb->scrub = scrub;
 156         aeb->copy_flag = aeb->sqnum = 0;
 157
 158         ai->ec_sum += aeb->ec;
 159         ai->ec_count++;
 160
 161         if (ai->max_ec < aeb->ec)
 162                 ai->max_ec = aeb->ec;
 163
 164         if (ai->min_ec > aeb->ec)
 165                 ai->min_ec = aeb->ec;
 166
 167         list_add_tail(&aeb->u.list, list);
 168
 169         return 0;
 170 }
 171
 172 /**
 173  * add_vol - create and add a new volume to ubi_attach_info.
 174  * @ai: ubi_attach_info object
 175  * @vol_id: VID of the new volume
 176  * @used_ebs: number of used EBS
 177  * @data_pad: data padding value of the new volume
 178  * @vol_type: volume type
 179  * @last_eb_bytes: number of bytes in the last LEB
 180  *
 181  * Returns the new struct ubi_ainf_volume on success.
 182  * NULL indicates an error.
 183  */
 184 static struct ubi_ainf_volume *add_vol(struct ubi_attach_info *ai, int vol_id,
 185                                        int used_ebs, int data_pad, u8 vol_type,
 186                                        int last_eb_bytes)
 187 {
 188         struct ubi_ainf_volume *av;
 189         struct rb_node **p = &ai->volumes.rb_node, *parent = NULL;
 190
 191         while (*p) {
 192                 parent = *p;
 193                 av = rb_entry(parent, struct ubi_ainf_volume, rb);
 194
 195                 if (vol_id > av->vol_id)
 196                         p = &(*p)->rb_left;
 197                 else if (vol_id < av->vol_id)
 198                         p = &(*p)->rb_right;
 199                 else
 200                         return ERR_PTR(-EINVAL);
 201         }
 202
 203         av = kmalloc(sizeof(struct ubi_ainf_volume), GFP_KERNEL);
 204         if (!av)
 205                 goto out;
 206
 207         av->highest_lnum = av->leb_count = av->used_ebs = 0;
 208         av->vol_id = vol_id;
 209         av->data_pad = data_pad;
 210         av->last_data_size = last_eb_bytes;
 211         av->compat = 0;
 212         av->vol_type = vol_type;
 213         av->root = RB_ROOT;
 214         if (av->vol_type == UBI_STATIC_VOLUME)
 215                 av->used_ebs = used_ebs;
 216
 217         dbg_bld("found volume (ID %i)", vol_id);
 218
 219         rb_link_node(&av->rb, parent, p);
 220         rb_insert_color(&av->rb, &ai->volumes);
 221
 222 out:
 223         return av;
 224 }
 225
 226 /**
 227  * assign_aeb_to_av - assigns a SEB to a given ainf_volume and removes it
 228  * from it's original list.
 229  * @ai: ubi_attach_info object
 230  * @aeb: the to be assigned SEB
 231  * @av: target scan volume
 232  */
 233 static void assign_aeb_to_av(struct ubi_attach_info *ai,
 234                              struct ubi_ainf_peb *aeb,
 235                              struct ubi_ainf_volume *av)
 236 {
 237         struct ubi_ainf_peb *tmp_aeb;
 238         struct rb_node **p = &ai->volumes.rb_node, *parent = NULL;
 239
 240         p = &av->root.rb_node;
 241         while (*p) {
 242                 parent = *p;
 243
 244                 tmp_aeb = rb_entry(parent, struct ubi_ainf_peb, u.rb);
 245                 if (aeb->lnum != tmp_aeb->lnum) {
 246                         if (aeb->lnum < tmp_aeb->lnum)
 247                                 p = &(*p)->rb_left;
 248                         else
 249                                 p = &(*p)->rb_right;
 250
 251                         continue;
 252                 } else
 253                         break;
 254         }
 255
 256         list_del(&aeb->u.list);
 257         av->leb_count++;
 258
 259         rb_link_node(&aeb->u.rb, parent, p);
 260         rb_insert_color(&aeb->u.rb, &av->root);
 261 }
 262
 263 /**
 264  * update_vol - inserts or updates a LEB which was found a pool.
 265  * @ubi: the UBI device object
 266  * @ai: attach info object
 267  * @av: the volume this LEB belongs to
 268  * @new_vh: the volume header derived from new_aeb
 269  * @new_aeb: the AEB to be examined
 270  *
 271  * Returns 0 on success, < 0 indicates an internal error.
 272  */
 273 static int update_vol(struct ubi_device *ubi, struct ubi_attach_info *ai,
 274                       struct ubi_ainf_volume *av, struct ubi_vid_hdr *new_vh,
 275                       struct ubi_ainf_peb *new_aeb)
 276 {
 277         struct rb_node **p = &av->root.rb_node, *parent = NULL;
 278         struct ubi_ainf_peb *aeb, *victim;
 279         int cmp_res;
 280
 281         while (*p) {
 282                 parent = *p;
 283                 aeb = rb_entry(parent, struct ubi_ainf_peb, u.rb);
 284
 285                 if (be32_to_cpu(new_vh->lnum) != aeb->lnum) {
 286                         if (be32_to_cpu(new_vh->lnum) < aeb->lnum)
 287                                 p = &(*p)->rb_left;
 288                         else
 289                                 p = &(*p)->rb_right;
 290
 291                         continue;
 292                 }
 293
 294                 /* This case can happen if the fastmap gets written
 295                  * because of a volume change (creation, deletion, ..).
 296                  * Then a PEB can be within the persistent EBA and the pool.
 297                  */
 298                 if (aeb->pnum == new_aeb->pnum) {
 299                         ubi_assert(aeb->lnum == new_aeb->lnum);
 300                         kmem_cache_free(ai->aeb_slab_cache, new_aeb);
 301
 302                         return 0;
 303                 }
 304
 305                 cmp_res = ubi_compare_lebs(ubi, aeb, new_aeb->pnum, new_vh);
 306                 if (cmp_res < 0)
 307                         return cmp_res;
 308
 309                 /* new_aeb is newer */
 310                 if (cmp_res & 1) {
 311                         victim = kmem_cache_alloc(ai->aeb_slab_cache,
 312                                 GFP_KERNEL);
 313                         if (!victim)
 314                                 return -ENOMEM;
 315
 316                         victim->ec = aeb->ec;
 317                         victim->pnum = aeb->pnum;
 318                         list_add_tail(&victim->u.list, &ai->erase);
 319
 320                         if (av->highest_lnum == be32_to_cpu(new_vh->lnum))
 321                                 av->last_data_size =
 322                                         be32_to_cpu(new_vh->data_size);
 323
 324                         dbg_bld("vol %i: AEB %i's PEB %i is the newer",
 325                                 av->vol_id, aeb->lnum, new_aeb->pnum);
 326
 327                         aeb->ec = new_aeb->ec;
 328                         aeb->pnum = new_aeb->pnum;
 329                         aeb->copy_flag = new_vh->copy_flag;
 330                         aeb->scrub = new_aeb->scrub;
 331                         kmem_cache_free(ai->aeb_slab_cache, new_aeb);
 332
 333                 /* new_aeb is older */
 334                 } else {
 335                         dbg_bld("vol %i: AEB %i's PEB %i is old, dropping it",
 336                                 av->vol_id, aeb->lnum, new_aeb->pnum);
 337                         list_add_tail(&new_aeb->u.list, &ai->erase);
 338                 }
 339
 340                 return 0;
 341         }
 342         /* This LEB is new, let's add it to the volume */
 343
 344         if (av->highest_lnum <= be32_to_cpu(new_vh->lnum)) {
 345                 av->highest_lnum = be32_to_cpu(new_vh->lnum);
 346                 av->last_data_size = be32_to_cpu(new_vh->data_size);
 347         }
 348
 349         if (av->vol_type == UBI_STATIC_VOLUME)
 350                 av->used_ebs = be32_to_cpu(new_vh->used_ebs);
 351
 352         av->leb_count++;
 353
 354         rb_link_node(&new_aeb->u.rb, parent, p);
 355         rb_insert_color(&new_aeb->u.rb, &av->root);
 356
 357         return 0;
 358 }
 359
 360 /**
 361  * process_pool_aeb - we found a non-empty PEB in a pool.
 362  * @ubi: UBI device object
 363  * @ai: attach info object
 364  * @new_vh: the volume header derived from new_aeb
 365  * @new_aeb: the AEB to be examined
 366  *
 367  * Returns 0 on success, < 0 indicates an internal error.
 368  */
 369 static int process_pool_aeb(struct ubi_device *ubi, struct ubi_attach_info *ai,
 370                             struct ubi_vid_hdr *new_vh,
 371                             struct ubi_ainf_peb *new_aeb)
 372 {
 373         struct ubi_ainf_volume *av, *tmp_av = NULL;
 374         struct rb_node **p = &ai->volumes.rb_node, *parent = NULL;
 375         int found = 0;
 376
 377         if (be32_to_cpu(new_vh->vol_id) == UBI_FM_SB_VOLUME_ID ||
 378                 be32_to_cpu(new_vh->vol_id) == UBI_FM_DATA_VOLUME_ID) {
 379                 kmem_cache_free(ai->aeb_slab_cache, new_aeb);
 380
 381                 return 0;
 382         }
 383
 384         /* Find the volume this SEB belongs to */
 385         while (*p) {
 386                 parent = *p;
 387                 tmp_av = rb_entry(parent, struct ubi_ainf_volume, rb);
 388
 389                 if (be32_to_cpu(new_vh->vol_id) > tmp_av->vol_id)
 390                         p = &(*p)->rb_left;
 391                 else if (be32_to_cpu(new_vh->vol_id) < tmp_av->vol_id)
 392                         p = &(*p)->rb_right;
 393                 else {
 394                         found = 1;
 395                         break;
 396                 }
 397         }
 398
 399         if (found)
 400                 av = tmp_av;
 401         else {
 402                 ubi_err(ubi, "orphaned volume in fastmap pool!");
 403                 kmem_cache_free(ai->aeb_slab_cache, new_aeb);
 404                 return UBI_BAD_FASTMAP;
 405         }
 406
 407         ubi_assert(be32_to_cpu(new_vh->vol_id) == av->vol_id);
 408
 409         return update_vol(ubi, ai, av, new_vh, new_aeb);
 410 }
 411
 412 /**
 413  * unmap_peb - unmap a PEB.
 414  * If fastmap detects a free PEB in the pool it has to check whether
 415  * this PEB has been unmapped after writing the fastmap.
 416  *
 417  * @ai: UBI attach info object
 418  * @pnum: The PEB to be unmapped
 419  */
 420 static void unmap_peb(struct ubi_attach_info *ai, int pnum)
 421 {
 422         struct ubi_ainf_volume *av;
 423         struct rb_node *node, *node2;
 424         struct ubi_ainf_peb *aeb;
 425
 426         for (node = rb_first(&ai->volumes); node; node = rb_next(node)) {
 427                 av = rb_entry(node, struct ubi_ainf_volume, rb);
 428
 429                 for (node2 = rb_first(&av->root); node2;
 430                      node2 = rb_next(node2)) {
 431                         aeb = rb_entry(node2, struct ubi_ainf_peb, u.rb);
 432                         if (aeb->pnum == pnum) {
 433                                 rb_erase(&aeb->u.rb, &av->root);
 434                                 av->leb_count--;
 435                                 kmem_cache_free(ai->aeb_slab_cache, aeb);
 436                                 return;
 437                         }
 438                 }
 439         }
 440 }
 441
 442 /**
 443  * scan_pool - scans a pool for changed (no longer empty PEBs).
 444  * @ubi: UBI device object
 445  * @ai: attach info object
 446  * @pebs: an array of all PEB numbers in the to be scanned pool
 447  * @pool_size: size of the pool (number of entries in @pebs)
 448  * @max_sqnum: pointer to the maximal sequence number
 449  * @free: list of PEBs which are most likely free (and go into @ai->free)
 450  *
 451  * Returns 0 on success, if the pool is unusable UBI_BAD_FASTMAP is returned.
 452  * < 0 indicates an internal error.
 453  */
 454 #ifndef __UBOOT__
 455 static int scan_pool(struct ubi_device *ubi, struct ubi_attach_info *ai,
 456                      __be32 *pebs, int pool_size, unsigned long long *max_sqnum,
 457                      struct list_head *free)
 458 #else
 459 static int scan_pool(struct ubi_device *ubi, struct ubi_attach_info *ai,
 460                      __be32 *pebs, int pool_size, unsigned long long *max_sqnum,
 461                      struct list_head *free)
 462 #endif
 463 {
 464         struct ubi_vid_hdr *vh;
 465         struct ubi_ec_hdr *ech;
 466         struct ubi_ainf_peb *new_aeb;
 467         int i, pnum, err, ret = 0;
 468
 469         ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
 470         if (!ech)
 471                 return -ENOMEM;
 472
 473         vh = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL);
 474         if (!vh) {
 475                 kfree(ech);
 476                 return -ENOMEM;
 477         }
 478
 479         dbg_bld("scanning fastmap pool: size = %i", pool_size);
 480
 481         /*
 482          * Now scan all PEBs in the pool to find changes which have been made
 483          * after the creation of the fastmap
 484          */
 485         for (i = 0; i < pool_size; i++) {
 486                 int scrub = 0;
 487                 int image_seq;
 488
 489                 pnum = be32_to_cpu(pebs[i]);
 490
 491                 if (ubi_io_is_bad(ubi, pnum)) {
 492                         ubi_err(ubi, "bad PEB in fastmap pool!");
 493                         ret = UBI_BAD_FASTMAP;
 494                         goto out;
 495                 }
 496
 497                 err = ubi_io_read_ec_hdr(ubi, pnum, ech, 0);
 498                 if (err && err != UBI_IO_BITFLIPS) {
 499                         ubi_err(ubi, "unable to read EC header! PEB:%i err:%i",
 500                                 pnum, err);
 501                         ret = err > 0 ? UBI_BAD_FASTMAP : err;
 502                         goto out;
 503                 } else if (err == UBI_IO_BITFLIPS)
 504                         scrub = 1;
 505
 506                 /*
 507                  * Older UBI implementations have image_seq set to zero, so
 508                  * we shouldn't fail if image_seq == 0.
 509                  */
 510                 image_seq = be32_to_cpu(ech->image_seq);
 511
 512                 if (image_seq && (image_seq != ubi->image_seq)) {
 513                         ubi_err(ubi, "bad image seq: 0x%x, expected: 0x%x",
 514                                 be32_to_cpu(ech->image_seq), ubi->image_seq);
 515                         ret = UBI_BAD_FASTMAP;
 516                         goto out;
 517                 }
 518
 519                 err = ubi_io_read_vid_hdr(ubi, pnum, vh, 0);
 520                 if (err == UBI_IO_FF || err == UBI_IO_FF_BITFLIPS) {
 521                         unsigned long long ec = be64_to_cpu(ech->ec);
 522                         unmap_peb(ai, pnum);
 523                         dbg_bld("Adding PEB to free: %i", pnum);
 524                         if (err == UBI_IO_FF_BITFLIPS)
 525                                 add_aeb(ai, free, pnum, ec, 1);
 526                         else
 527                                 add_aeb(ai, free, pnum, ec, 0);
 528                         continue;
 529                 } else if (err == 0 || err == UBI_IO_BITFLIPS) {
 530                         dbg_bld("Found non empty PEB:%i in pool", pnum);
 531
 532                         if (err == UBI_IO_BITFLIPS)
 533                                 scrub = 1;
 534
 535                         new_aeb = kmem_cache_alloc(ai->aeb_slab_cache,
 536                                                    GFP_KERNEL);
 537                         if (!new_aeb) {
 538                                 ret = -ENOMEM;
 539                                 goto out;
 540                         }
 541
 542                         new_aeb->ec = be64_to_cpu(ech->ec);
 543                         new_aeb->pnum = pnum;
 544                         new_aeb->lnum = be32_to_cpu(vh->lnum);
 545                         new_aeb->sqnum = be64_to_cpu(vh->sqnum);
 546                         new_aeb->copy_flag = vh->copy_flag;
 547                         new_aeb->scrub = scrub;
 548
 549                         if (*max_sqnum < new_aeb->sqnum)
 550                                 *max_sqnum = new_aeb->sqnum;
 551
 552                         err = process_pool_aeb(ubi, ai, vh, new_aeb);
 553                         if (err) {
 554                                 ret = err > 0 ? UBI_BAD_FASTMAP : err;
 555                                 goto out;
 556                         }
 557                 } else {
 558                         /* We are paranoid and fall back to scanning mode */
 559                         ubi_err(ubi, "fastmap pool PEBs contains damaged PEBs!");
 560                         ret = err > 0 ? UBI_BAD_FASTMAP : err;
 561                         goto out;
 562                 }
 563
 564         }
 565
 566 out:
 567         ubi_free_vid_hdr(ubi, vh);
 568         kfree(ech);
 569         return ret;
 570 }
 571
 572 /**
 573  * count_fastmap_pebs - Counts the PEBs found by fastmap.
 574  * @ai: The UBI attach info object
 575  */
 576 static int count_fastmap_pebs(struct ubi_attach_info *ai)
 577 {
 578         struct ubi_ainf_peb *aeb;
 579         struct ubi_ainf_volume *av;
 580         struct rb_node *rb1, *rb2;
 581         int n = 0;
 582
 583         list_for_each_entry(aeb, &ai->erase, u.list)
 584                 n++;
 585
 586         list_for_each_entry(aeb, &ai->free, u.list)
 587                 n++;
 588
 589          ubi_rb_for_each_entry(rb1, av, &ai->volumes, rb)
 590                 ubi_rb_for_each_entry(rb2, aeb, &av->root, u.rb)
 591                         n++;
 592
 593         return n;
 594 }
 595
 596 /**
 597  * ubi_attach_fastmap - creates ubi_attach_info from a fastmap.
 598  * @ubi: UBI device object
 599  * @ai: UBI attach info object
 600  * @fm: the fastmap to be attached
 601  *
 602  * Returns 0 on success, UBI_BAD_FASTMAP if the found fastmap was unusable.
 603  * < 0 indicates an internal error.
 604  */
 605 static int ubi_attach_fastmap(struct ubi_device *ubi,
 606                               struct ubi_attach_info *ai,
 607                               struct ubi_fastmap_layout *fm)
 608 {
 609         struct list_head used, free;
 610         struct ubi_ainf_volume *av;
 611         struct ubi_ainf_peb *aeb, *tmp_aeb, *_tmp_aeb;
 612         struct ubi_fm_sb *fmsb;
 613         struct ubi_fm_hdr *fmhdr;
 614         struct ubi_fm_scan_pool *fmpl, *fmpl_wl;
 615         struct ubi_fm_ec *fmec;
 616         struct ubi_fm_volhdr *fmvhdr;
 617         struct ubi_fm_eba *fm_eba;
 618         int ret, i, j, pool_size, wl_pool_size;
 619         size_t fm_pos = 0, fm_size = ubi->fm_size;
 620         unsigned long long max_sqnum = 0;
 621         void *fm_raw = ubi->fm_buf;
 622
 623         INIT_LIST_HEAD(&used);
 624         INIT_LIST_HEAD(&free);
 625         ai->min_ec = UBI_MAX_ERASECOUNTER;
 626
 627         fmsb = (struct ubi_fm_sb *)(fm_raw);
 628         ai->max_sqnum = fmsb->sqnum;
 629         fm_pos += sizeof(struct ubi_fm_sb);
 630         if (fm_pos >= fm_size)
 631                 goto fail_bad;
 632
 633         fmhdr = (struct ubi_fm_hdr *)(fm_raw + fm_pos);
 634         fm_pos += sizeof(*fmhdr);
 635         if (fm_pos >= fm_size)
 636                 goto fail_bad;
 637
 638         if (be32_to_cpu(fmhdr->magic) != UBI_FM_HDR_MAGIC) {
 639                 ubi_err(ubi, "bad fastmap header magic: 0x%x, expected: 0x%x",
 640                         be32_to_cpu(fmhdr->magic), UBI_FM_HDR_MAGIC);
 641                 goto fail_bad;
 642         }
 643
 644         fmpl = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
 645         fm_pos += sizeof(*fmpl);
 646         if (fm_pos >= fm_size)
 647                 goto fail_bad;
 648         if (be32_to_cpu(fmpl->magic) != UBI_FM_POOL_MAGIC) {
 649                 ubi_err(ubi, "bad fastmap pool magic: 0x%x, expected: 0x%x",
 650                         be32_to_cpu(fmpl->magic), UBI_FM_POOL_MAGIC);
 651                 goto fail_bad;
 652         }
 653
 654         fmpl_wl = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
 655         fm_pos += sizeof(*fmpl_wl);
 656         if (fm_pos >= fm_size)
 657                 goto fail_bad;
 658         if (be32_to_cpu(fmpl_wl->magic) != UBI_FM_POOL_MAGIC) {
 659                 ubi_err(ubi, "bad fastmap WL pool magic: 0x%x, expected: 0x%x",
 660                         be32_to_cpu(fmpl_wl->magic), UBI_FM_POOL_MAGIC);
 661                 goto fail_bad;
 662         }
 663
 664         pool_size = be16_to_cpu(fmpl->size);
 665         wl_pool_size = be16_to_cpu(fmpl_wl->size);
 666         fm->max_pool_size = be16_to_cpu(fmpl->max_size);
 667         fm->max_wl_pool_size = be16_to_cpu(fmpl_wl->max_size);
 668
 669         if (pool_size > UBI_FM_MAX_POOL_SIZE || pool_size < 0) {
 670                 ubi_err(ubi, "bad pool size: %i", pool_size);
 671                 goto fail_bad;
 672         }
 673
 674         if (wl_pool_size > UBI_FM_MAX_POOL_SIZE || wl_pool_size < 0) {
 675                 ubi_err(ubi, "bad WL pool size: %i", wl_pool_size);
 676                 goto fail_bad;
 677         }
 678
 679
 680         if (fm->max_pool_size > UBI_FM_MAX_POOL_SIZE ||
 681             fm->max_pool_size < 0) {
 682                 ubi_err(ubi, "bad maximal pool size: %i", fm->max_pool_size);
 683                 goto fail_bad;
 684         }
 685
 686         if (fm->max_wl_pool_size > UBI_FM_MAX_POOL_SIZE ||
 687             fm->max_wl_pool_size < 0) {
 688                 ubi_err(ubi, "bad maximal WL pool size: %i",
 689                         fm->max_wl_pool_size);
 690                 goto fail_bad;
 691         }
 692
 693         /* read EC values from free list */
 694         for (i = 0; i < be32_to_cpu(fmhdr->free_peb_count); i++) {
 695                 fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
 696                 fm_pos += sizeof(*fmec);
 697                 if (fm_pos >= fm_size)
 698                         goto fail_bad;
 699
 700                 add_aeb(ai, &ai->free, be32_to_cpu(fmec->pnum),
 701                         be32_to_cpu(fmec->ec), 0);
 702         }
 703
 704         /* read EC values from used list */
 705         for (i = 0; i < be32_to_cpu(fmhdr->used_peb_count); i++) {
 706                 fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
 707                 fm_pos += sizeof(*fmec);
 708                 if (fm_pos >= fm_size)
 709                         goto fail_bad;
 710
 711                 add_aeb(ai, &used, be32_to_cpu(fmec->pnum),
 712                         be32_to_cpu(fmec->ec), 0);
 713         }
 714
 715         /* read EC values from scrub list */
 716         for (i = 0; i < be32_to_cpu(fmhdr->scrub_peb_count); i++) {
 717                 fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
 718                 fm_pos += sizeof(*fmec);
 719                 if (fm_pos >= fm_size)
 720                         goto fail_bad;
 721
 722                 add_aeb(ai, &used, be32_to_cpu(fmec->pnum),
 723                         be32_to_cpu(fmec->ec), 1);
 724         }
 725
 726         /* read EC values from erase list */
 727         for (i = 0; i < be32_to_cpu(fmhdr->erase_peb_count); i++) {
 728                 fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
 729                 fm_pos += sizeof(*fmec);
 730                 if (fm_pos >= fm_size)
 731                         goto fail_bad;
 732
 733                 add_aeb(ai, &ai->erase, be32_to_cpu(fmec->pnum),
 734                         be32_to_cpu(fmec->ec), 1);
 735         }
 736
 737         ai->mean_ec = div_u64(ai->ec_sum, ai->ec_count);
 738         ai->bad_peb_count = be32_to_cpu(fmhdr->bad_peb_count);
 739
 740         /* Iterate over all volumes and read their EBA table */
 741         for (i = 0; i < be32_to_cpu(fmhdr->vol_count); i++) {
 742                 fmvhdr = (struct ubi_fm_volhdr *)(fm_raw + fm_pos);
 743                 fm_pos += sizeof(*fmvhdr);
 744                 if (fm_pos >= fm_size)
 745                         goto fail_bad;
 746
 747                 if (be32_to_cpu(fmvhdr->magic) != UBI_FM_VHDR_MAGIC) {
 748                         ubi_err(ubi, "bad fastmap vol header magic: 0x%x, expected: 0x%x",
 749                                 be32_to_cpu(fmvhdr->magic), UBI_FM_VHDR_MAGIC);
 750                         goto fail_bad;
 751                 }
 752
 753                 av = add_vol(ai, be32_to_cpu(fmvhdr->vol_id),
 754                              be32_to_cpu(fmvhdr->used_ebs),
 755                              be32_to_cpu(fmvhdr->data_pad),
 756                              fmvhdr->vol_type,
 757                              be32_to_cpu(fmvhdr->last_eb_bytes));
 758
 759                 if (!av)
 760                         goto fail_bad;
 761                 if (PTR_ERR(av) == -EINVAL) {
 762                         ubi_err(ubi, "volume (ID %i) already exists",
 763                                 fmvhdr->vol_id);
 764                         goto fail_bad;
 765                 }
 766
 767                 ai->vols_found++;
 768                 if (ai->highest_vol_id < be32_to_cpu(fmvhdr->vol_id))
 769                         ai->highest_vol_id = be32_to_cpu(fmvhdr->vol_id);
 770
 771                 fm_eba = (struct ubi_fm_eba *)(fm_raw + fm_pos);
 772                 fm_pos += sizeof(*fm_eba);
 773                 fm_pos += (sizeof(__be32) * be32_to_cpu(fm_eba->reserved_pebs));
 774                 if (fm_pos >= fm_size)
 775                         goto fail_bad;
 776
 777                 if (be32_to_cpu(fm_eba->magic) != UBI_FM_EBA_MAGIC) {
 778                         ubi_err(ubi, "bad fastmap EBA header magic: 0x%x, expected: 0x%x",
 779                                 be32_to_cpu(fm_eba->magic), UBI_FM_EBA_MAGIC);
 780                         goto fail_bad;
 781                 }
 782
 783                 for (j = 0; j < be32_to_cpu(fm_eba->reserved_pebs); j++) {
 784                         int pnum = be32_to_cpu(fm_eba->pnum[j]);
 785
 786                         if ((int)be32_to_cpu(fm_eba->pnum[j]) < 0)
 787                                 continue;
 788
 789                         aeb = NULL;
 790                         list_for_each_entry(tmp_aeb, &used, u.list) {
 791                                 if (tmp_aeb->pnum == pnum) {
 792                                         aeb = tmp_aeb;
 793                                         break;
 794                                 }
 795                         }
 796
 797                         if (!aeb) {
 798                                 ubi_err(ubi, "PEB %i is in EBA but not in used list", pnum);
 799                                 goto fail_bad;
 800                         }
 801
 802                         aeb->lnum = j;
 803
 804                         if (av->highest_lnum <= aeb->lnum)
 805                                 av->highest_lnum = aeb->lnum;
 806
 807                         assign_aeb_to_av(ai, aeb, av);
 808
 809                         dbg_bld("inserting PEB:%i (LEB %i) to vol %i",
 810                                 aeb->pnum, aeb->lnum, av->vol_id);
 811                 }
 812         }
 813
 814         ret = scan_pool(ubi, ai, fmpl->pebs, pool_size, &max_sqnum, &free);
 815         if (ret)
 816                 goto fail;
 817
 818         ret = scan_pool(ubi, ai, fmpl_wl->pebs, wl_pool_size, &max_sqnum, &free);
 819         if (ret)
 820                 goto fail;
 821
 822         if (max_sqnum > ai->max_sqnum)
 823                 ai->max_sqnum = max_sqnum;
 824
 825         list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &free, u.list)
 826                 list_move_tail(&tmp_aeb->u.list, &ai->free);
 827
 828         list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &used, u.list)
 829                 list_move_tail(&tmp_aeb->u.list, &ai->erase);
 830
 831         ubi_assert(list_empty(&free));
 832
 833         /*
 834          * If fastmap is leaking PEBs (must not happen), raise a
 835          * fat warning and fall back to scanning mode.
 836          * We do this here because in ubi_wl_init() it's too late
 837          * and we cannot fall back to scanning.
 838          */
 839 #ifndef __UBOOT__
 840         if (WARN_ON(count_fastmap_pebs(ai) != ubi->peb_count -
 841                     ai->bad_peb_count - fm->used_blocks))
 842                 goto fail_bad;
 843 #else
 844         if (count_fastmap_pebs(ai) != ubi->peb_count -
 845                     ai->bad_peb_count - fm->used_blocks) {
 846                 WARN_ON(1);
 847                 goto fail_bad;
 848         }
 849 #endif
 850
 851         return 0;
 852
 853 fail_bad:
 854         ret = UBI_BAD_FASTMAP;
 855 fail:
 856         list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &used, u.list) {
 857                 list_del(&tmp_aeb->u.list);
 858                 kmem_cache_free(ai->aeb_slab_cache, tmp_aeb);
 859         }
 860         list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &free, u.list) {
 861                 list_del(&tmp_aeb->u.list);
 862                 kmem_cache_free(ai->aeb_slab_cache, tmp_aeb);
 863         }
 864
 865         return ret;
 866 }
 867
 868 /**
 869  * ubi_scan_fastmap - scan the fastmap.
 870  * @ubi: UBI device object
 871  * @ai: UBI attach info to be filled
 872  * @fm_anchor: The fastmap starts at this PEB
 873  *
 874  * Returns 0 on success, UBI_NO_FASTMAP if no fastmap was found,
 875  * UBI_BAD_FASTMAP if one was found but is not usable.
 876  * < 0 indicates an internal error.
 877  */
 878 int ubi_scan_fastmap(struct ubi_device *ubi, struct ubi_attach_info *ai,
 879                      int fm_anchor)
 880 {
 881         struct ubi_fm_sb *fmsb, *fmsb2;
 882         struct ubi_vid_hdr *vh;
 883         struct ubi_ec_hdr *ech;
 884         struct ubi_fastmap_layout *fm;
 885         int i, used_blocks, pnum, ret = 0;
 886         size_t fm_size;
 887         __be32 crc, tmp_crc;
 888         unsigned long long sqnum = 0;
 889
 890         down_write(&ubi->fm_protect);
 891         memset(ubi->fm_buf, 0, ubi->fm_size);
 892
 893         fmsb = kmalloc(sizeof(*fmsb), GFP_KERNEL);
 894         if (!fmsb) {
 895                 ret = -ENOMEM;
 896                 goto out;
 897         }
 898
 899         fm = kzalloc(sizeof(*fm), GFP_KERNEL);
 900         if (!fm) {
 901                 ret = -ENOMEM;
 902                 kfree(fmsb);
 903                 goto out;
 904         }
 905
 906         ret = ubi_io_read(ubi, fmsb, fm_anchor, ubi->leb_start, sizeof(*fmsb));
 907         if (ret && ret != UBI_IO_BITFLIPS)
 908                 goto free_fm_sb;
 909         else if (ret == UBI_IO_BITFLIPS)
 910                 fm->to_be_tortured[0] = 1;
 911
 912         if (be32_to_cpu(fmsb->magic) != UBI_FM_SB_MAGIC) {
 913                 ubi_err(ubi, "bad super block magic: 0x%x, expected: 0x%x",
 914                         be32_to_cpu(fmsb->magic), UBI_FM_SB_MAGIC);
 915                 ret = UBI_BAD_FASTMAP;
 916                 goto free_fm_sb;
 917         }
 918
 919         if (fmsb->version != UBI_FM_FMT_VERSION) {
 920                 ubi_err(ubi, "bad fastmap version: %i, expected: %i",
 921                         fmsb->version, UBI_FM_FMT_VERSION);
 922                 ret = UBI_BAD_FASTMAP;
 923                 goto free_fm_sb;
 924         }
 925
 926         used_blocks = be32_to_cpu(fmsb->used_blocks);
 927         if (used_blocks > UBI_FM_MAX_BLOCKS || used_blocks < 1) {
 928                 ubi_err(ubi, "number of fastmap blocks is invalid: %i",
 929                         used_blocks);
 930                 ret = UBI_BAD_FASTMAP;
 931                 goto free_fm_sb;
 932         }
 933
 934         fm_size = ubi->leb_size * used_blocks;
 935         if (fm_size != ubi->fm_size) {
 936                 ubi_err(ubi, "bad fastmap size: %zi, expected: %zi",
 937                         fm_size, ubi->fm_size);
 938                 ret = UBI_BAD_FASTMAP;
 939                 goto free_fm_sb;
 940         }
 941
 942         ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
 943         if (!ech) {
 944                 ret = -ENOMEM;
 945                 goto free_fm_sb;
 946         }
 947
 948         vh = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL);
 949         if (!vh) {
 950                 ret = -ENOMEM;
 951                 goto free_hdr;
 952         }
 953
 954         for (i = 0; i < used_blocks; i++) {
 955                 int image_seq;
 956
 957                 pnum = be32_to_cpu(fmsb->block_loc[i]);
 958
 959                 if (ubi_io_is_bad(ubi, pnum)) {
 960                         ret = UBI_BAD_FASTMAP;
 961                         goto free_hdr;
 962                 }
 963
 964                 ret = ubi_io_read_ec_hdr(ubi, pnum, ech, 0);
 965                 if (ret && ret != UBI_IO_BITFLIPS) {
 966                         ubi_err(ubi, "unable to read fastmap block# %i EC (PEB: %i)",
 967                                 i, pnum);
 968                         if (ret > 0)
 969                                 ret = UBI_BAD_FASTMAP;
 970                         goto free_hdr;
 971                 } else if (ret == UBI_IO_BITFLIPS)
 972                         fm->to_be_tortured[i] = 1;
 973
 974                 image_seq = be32_to_cpu(ech->image_seq);
 975                 if (!ubi->image_seq)
 976                         ubi->image_seq = image_seq;
 977
 978                 /*
 979                  * Older UBI implementations have image_seq set to zero, so
 980                  * we shouldn't fail if image_seq == 0.
 981                  */
 982                 if (image_seq && (image_seq != ubi->image_seq)) {
 983                         ubi_err(ubi, "wrong image seq:%d instead of %d",
 984                                 be32_to_cpu(ech->image_seq), ubi->image_seq);
 985                         ret = UBI_BAD_FASTMAP;
 986                         goto free_hdr;
 987                 }
 988
 989                 ret = ubi_io_read_vid_hdr(ubi, pnum, vh, 0);
 990                 if (ret && ret != UBI_IO_BITFLIPS) {
 991                         ubi_err(ubi, "unable to read fastmap block# %i (PEB: %i)",
 992                                 i, pnum);
 993                         goto free_hdr;
 994                 }
 995
 996                 if (i == 0) {
 997                         if (be32_to_cpu(vh->vol_id) != UBI_FM_SB_VOLUME_ID) {
 998                                 ubi_err(ubi, "bad fastmap anchor vol_id: 0x%x, expected: 0x%x",
 999                                         be32_to_cpu(vh->vol_id),
1000                                         UBI_FM_SB_VOLUME_ID);
1001                                 ret = UBI_BAD_FASTMAP;
1002                                 goto free_hdr;
1003                         }
1004                 } else {
1005                         if (be32_to_cpu(vh->vol_id) != UBI_FM_DATA_VOLUME_ID) {
1006                                 ubi_err(ubi, "bad fastmap data vol_id: 0x%x, expected: 0x%x",
1007                                         be32_to_cpu(vh->vol_id),
1008                                         UBI_FM_DATA_VOLUME_ID);
1009                                 ret = UBI_BAD_FASTMAP;
1010                                 goto free_hdr;
1011                         }
1012                 }
1013
1014                 if (sqnum < be64_to_cpu(vh->sqnum))
1015                         sqnum = be64_to_cpu(vh->sqnum);
1016
1017                 ret = ubi_io_read(ubi, ubi->fm_buf + (ubi->leb_size * i), pnum,
1018                                   ubi->leb_start, ubi->leb_size);
1019                 if (ret && ret != UBI_IO_BITFLIPS) {
1020                         ubi_err(ubi, "unable to read fastmap block# %i (PEB: %i, "
1021                                 "err: %i)", i, pnum, ret);
1022                         goto free_hdr;
1023                 }
1024         }
1025
1026         kfree(fmsb);
1027         fmsb = NULL;
1028
1029         fmsb2 = (struct ubi_fm_sb *)(ubi->fm_buf);
1030         tmp_crc = be32_to_cpu(fmsb2->data_crc);
1031         fmsb2->data_crc = 0;
1032         crc = crc32(UBI_CRC32_INIT, ubi->fm_buf, fm_size);
1033         if (crc != tmp_crc) {
1034                 ubi_err(ubi, "fastmap data CRC is invalid");
1035                 ubi_err(ubi, "CRC should be: 0x%x, calc: 0x%x",
1036                         tmp_crc, crc);
1037                 ret = UBI_BAD_FASTMAP;
1038                 goto free_hdr;
1039         }
1040
1041         fmsb2->sqnum = sqnum;
1042
1043         fm->used_blocks = used_blocks;
1044
1045         ret = ubi_attach_fastmap(ubi, ai, fm);
1046         if (ret) {
1047                 if (ret > 0)
1048                         ret = UBI_BAD_FASTMAP;
1049                 goto free_hdr;
1050         }
1051
1052         for (i = 0; i < used_blocks; i++) {
1053                 struct ubi_wl_entry *e;
1054
1055                 e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL);
1056                 if (!e) {
1057                         while (i--)
1058                                 kfree(fm->e[i]);
1059
1060                         ret = -ENOMEM;
1061                         goto free_hdr;
1062                 }
1063
1064                 e->pnum = be32_to_cpu(fmsb2->block_loc[i]);
1065                 e->ec = be32_to_cpu(fmsb2->block_ec[i]);
1066                 fm->e[i] = e;
1067         }
1068
1069         ubi->fm = fm;
1070         ubi->fm_pool.max_size = ubi->fm->max_pool_size;
1071         ubi->fm_wl_pool.max_size = ubi->fm->max_wl_pool_size;
1072         ubi_msg(ubi, "attached by fastmap");
1073         ubi_msg(ubi, "fastmap pool size: %d", ubi->fm_pool.max_size);
1074         ubi_msg(ubi, "fastmap WL pool size: %d",
1075                 ubi->fm_wl_pool.max_size);
1076         ubi->fm_disabled = 0;
1077
1078         ubi_free_vid_hdr(ubi, vh);
1079         kfree(ech);
1080 out:
1081         up_write(&ubi->fm_protect);
1082         if (ret == UBI_BAD_FASTMAP)
1083                 ubi_err(ubi, "Attach by fastmap failed, doing a full scan!");
1084         return ret;
1085
1086 free_hdr:
1087         ubi_free_vid_hdr(ubi, vh);
1088         kfree(ech);
1089 free_fm_sb:
1090         kfree(fmsb);
1091         kfree(fm);
1092         goto out;
1093 }
1094
1095 /**
1096  * ubi_write_fastmap - writes a fastmap.
1097  * @ubi: UBI device object
1098  * @new_fm: the to be written fastmap
1099  *
1100  * Returns 0 on success, < 0 indicates an internal error.
1101  */
1102 static int ubi_write_fastmap(struct ubi_device *ubi,
1103                              struct ubi_fastmap_layout *new_fm)
1104 {
1105         size_t fm_pos = 0;
1106         void *fm_raw;
1107         struct ubi_fm_sb *fmsb;
1108         struct ubi_fm_hdr *fmh;
1109         struct ubi_fm_scan_pool *fmpl, *fmpl_wl;
1110         struct ubi_fm_ec *fec;
1111         struct ubi_fm_volhdr *fvh;
1112         struct ubi_fm_eba *feba;
1113         struct ubi_wl_entry *wl_e;
1114         struct ubi_volume *vol;
1115         struct ubi_vid_hdr *avhdr, *dvhdr;
1116         struct ubi_work *ubi_wrk;
1117         struct rb_node *tmp_rb;
1118         int ret, i, j, free_peb_count, used_peb_count, vol_count;
1119         int scrub_peb_count, erase_peb_count;
1120         int *seen_pebs = NULL;
1121
1122         fm_raw = ubi->fm_buf;
1123         memset(ubi->fm_buf, 0, ubi->fm_size);
1124
1125         avhdr = new_fm_vhdr(ubi, UBI_FM_SB_VOLUME_ID);
1126         if (!avhdr) {
1127                 ret = -ENOMEM;
1128                 goto out;
1129         }
1130
1131         dvhdr = new_fm_vhdr(ubi, UBI_FM_DATA_VOLUME_ID);
1132         if (!dvhdr) {
1133                 ret = -ENOMEM;
1134                 goto out_kfree;
1135         }
1136
1137         seen_pebs = init_seen(ubi);
1138         if (IS_ERR(seen_pebs)) {
1139                 ret = PTR_ERR(seen_pebs);
1140                 goto out_kfree;
1141         }
1142
1143         spin_lock(&ubi->volumes_lock);
1144         spin_lock(&ubi->wl_lock);
1145
1146         fmsb = (struct ubi_fm_sb *)fm_raw;
1147         fm_pos += sizeof(*fmsb);
1148         ubi_assert(fm_pos <= ubi->fm_size);
1149
1150         fmh = (struct ubi_fm_hdr *)(fm_raw + fm_pos);
1151         fm_pos += sizeof(*fmh);
1152         ubi_assert(fm_pos <= ubi->fm_size);
1153
1154         fmsb->magic = cpu_to_be32(UBI_FM_SB_MAGIC);
1155         fmsb->version = UBI_FM_FMT_VERSION;
1156         fmsb->used_blocks = cpu_to_be32(new_fm->used_blocks);
1157         /* the max sqnum will be filled in while *reading* the fastmap */
1158         fmsb->sqnum = 0;
1159
1160         fmh->magic = cpu_to_be32(UBI_FM_HDR_MAGIC);
1161         free_peb_count = 0;
1162         used_peb_count = 0;
1163         scrub_peb_count = 0;
1164         erase_peb_count = 0;
1165         vol_count = 0;
1166
1167         fmpl = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
1168         fm_pos += sizeof(*fmpl);
1169         fmpl->magic = cpu_to_be32(UBI_FM_POOL_MAGIC);
1170         fmpl->size = cpu_to_be16(ubi->fm_pool.size);
1171         fmpl->max_size = cpu_to_be16(ubi->fm_pool.max_size);
1172
1173         for (i = 0; i < ubi->fm_pool.size; i++) {
1174                 fmpl->pebs[i] = cpu_to_be32(ubi->fm_pool.pebs[i]);
1175                 set_seen(ubi, ubi->fm_pool.pebs[i], seen_pebs);
1176         }
1177
1178         fmpl_wl = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
1179         fm_pos += sizeof(*fmpl_wl);
1180         fmpl_wl->magic = cpu_to_be32(UBI_FM_POOL_MAGIC);
1181         fmpl_wl->size = cpu_to_be16(ubi->fm_wl_pool.size);
1182         fmpl_wl->max_size = cpu_to_be16(ubi->fm_wl_pool.max_size);
1183
1184         for (i = 0; i < ubi->fm_wl_pool.size; i++) {
1185                 fmpl_wl->pebs[i] = cpu_to_be32(ubi->fm_wl_pool.pebs[i]);
1186                 set_seen(ubi, ubi->fm_wl_pool.pebs[i], seen_pebs);
1187         }
1188
1189         ubi_for_each_free_peb(ubi, wl_e, tmp_rb) {
1190                 fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1191
1192                 fec->pnum = cpu_to_be32(wl_e->pnum);
1193                 set_seen(ubi, wl_e->pnum, seen_pebs);
1194                 fec->ec = cpu_to_be32(wl_e->ec);
1195
1196                 free_peb_count++;
1197                 fm_pos += sizeof(*fec);
1198                 ubi_assert(fm_pos <= ubi->fm_size);
1199         }
1200         fmh->free_peb_count = cpu_to_be32(free_peb_count);
1201
1202         ubi_for_each_used_peb(ubi, wl_e, tmp_rb) {
1203                 fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1204
1205                 fec->pnum = cpu_to_be32(wl_e->pnum);
1206                 set_seen(ubi, wl_e->pnum, seen_pebs);
1207                 fec->ec = cpu_to_be32(wl_e->ec);
1208
1209                 used_peb_count++;
1210                 fm_pos += sizeof(*fec);
1211                 ubi_assert(fm_pos <= ubi->fm_size);
1212         }
1213
1214         ubi_for_each_protected_peb(ubi, i, wl_e) {
1215                 fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1216
1217                 fec->pnum = cpu_to_be32(wl_e->pnum);
1218                 set_seen(ubi, wl_e->pnum, seen_pebs);
1219                 fec->ec = cpu_to_be32(wl_e->ec);
1220
1221                 used_peb_count++;
1222                 fm_pos += sizeof(*fec);
1223                 ubi_assert(fm_pos <= ubi->fm_size);
1224         }
1225         fmh->used_peb_count = cpu_to_be32(used_peb_count);
1226
1227         ubi_for_each_scrub_peb(ubi, wl_e, tmp_rb) {
1228                 fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1229
1230                 fec->pnum = cpu_to_be32(wl_e->pnum);
1231                 set_seen(ubi, wl_e->pnum, seen_pebs);
1232                 fec->ec = cpu_to_be32(wl_e->ec);
1233
1234                 scrub_peb_count++;
1235                 fm_pos += sizeof(*fec);
1236                 ubi_assert(fm_pos <= ubi->fm_size);
1237         }
1238         fmh->scrub_peb_count = cpu_to_be32(scrub_peb_count);
1239
1240
1241         list_for_each_entry(ubi_wrk, &ubi->works, list) {
1242                 if (ubi_is_erase_work(ubi_wrk)) {
1243                         wl_e = ubi_wrk->e;
1244                         ubi_assert(wl_e);
1245
1246                         fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1247
1248                         fec->pnum = cpu_to_be32(wl_e->pnum);
1249                         set_seen(ubi, wl_e->pnum, seen_pebs);
1250                         fec->ec = cpu_to_be32(wl_e->ec);
1251
1252                         erase_peb_count++;
1253                         fm_pos += sizeof(*fec);
1254                         ubi_assert(fm_pos <= ubi->fm_size);
1255                 }
1256         }
1257         fmh->erase_peb_count = cpu_to_be32(erase_peb_count);
1258
1259         for (i = 0; i < UBI_MAX_VOLUMES + UBI_INT_VOL_COUNT; i++) {
1260                 vol = ubi->volumes[i];
1261
1262                 if (!vol)
1263                         continue;
1264
1265                 vol_count++;
1266
1267                 fvh = (struct ubi_fm_volhdr *)(fm_raw + fm_pos);
1268                 fm_pos += sizeof(*fvh);
1269                 ubi_assert(fm_pos <= ubi->fm_size);
1270
1271                 fvh->magic = cpu_to_be32(UBI_FM_VHDR_MAGIC);
1272                 fvh->vol_id = cpu_to_be32(vol->vol_id);
1273                 fvh->vol_type = vol->vol_type;
1274                 fvh->used_ebs = cpu_to_be32(vol->used_ebs);
1275                 fvh->data_pad = cpu_to_be32(vol->data_pad);
1276                 fvh->last_eb_bytes = cpu_to_be32(vol->last_eb_bytes);
1277
1278                 ubi_assert(vol->vol_type == UBI_DYNAMIC_VOLUME ||
1279                         vol->vol_type == UBI_STATIC_VOLUME);
1280
1281                 feba = (struct ubi_fm_eba *)(fm_raw + fm_pos);
1282                 fm_pos += sizeof(*feba) + (sizeof(__be32) * vol->reserved_pebs);
1283                 ubi_assert(fm_pos <= ubi->fm_size);
1284
1285                 for (j = 0; j < vol->reserved_pebs; j++)
1286                         feba->pnum[j] = cpu_to_be32(vol->eba_tbl[j]);
1287
1288                 feba->reserved_pebs = cpu_to_be32(j);
1289                 feba->magic = cpu_to_be32(UBI_FM_EBA_MAGIC);
1290         }
1291         fmh->vol_count = cpu_to_be32(vol_count);
1292         fmh->bad_peb_count = cpu_to_be32(ubi->bad_peb_count);
1293
1294         avhdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));
1295         avhdr->lnum = 0;
1296
1297         spin_unlock(&ubi->wl_lock);
1298         spin_unlock(&ubi->volumes_lock);
1299
1300         dbg_bld("writing fastmap SB to PEB %i", new_fm->e[0]->pnum);
1301         ret = ubi_io_write_vid_hdr(ubi, new_fm->e[0]->pnum, avhdr);
1302         if (ret) {
1303                 ubi_err(ubi, "unable to write vid_hdr to fastmap SB!");
1304                 goto out_kfree;
1305         }
1306
1307         for (i = 0; i < new_fm->used_blocks; i++) {
1308                 fmsb->block_loc[i] = cpu_to_be32(new_fm->e[i]->pnum);
1309                 set_seen(ubi, new_fm->e[i]->pnum, seen_pebs);
1310                 fmsb->block_ec[i] = cpu_to_be32(new_fm->e[i]->ec);
1311         }
1312
1313         fmsb->data_crc = 0;
1314         fmsb->data_crc = cpu_to_be32(crc32(UBI_CRC32_INIT, fm_raw,
1315                                            ubi->fm_size));
1316
1317         for (i = 1; i < new_fm->used_blocks; i++) {
1318                 dvhdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));
1319                 dvhdr->lnum = cpu_to_be32(i);
1320                 dbg_bld("writing fastmap data to PEB %i sqnum %llu",
1321                         new_fm->e[i]->pnum, be64_to_cpu(dvhdr->sqnum));
1322                 ret = ubi_io_write_vid_hdr(ubi, new_fm->e[i]->pnum, dvhdr);
1323                 if (ret) {
1324                         ubi_err(ubi, "unable to write vid_hdr to PEB %i!",
1325                                 new_fm->e[i]->pnum);
1326                         goto out_kfree;
1327                 }
1328         }
1329
1330         for (i = 0; i < new_fm->used_blocks; i++) {
1331                 ret = ubi_io_write(ubi, fm_raw + (i * ubi->leb_size),
1332                         new_fm->e[i]->pnum, ubi->leb_start, ubi->leb_size);
1333                 if (ret) {
1334                         ubi_err(ubi, "unable to write fastmap to PEB %i!",
1335                                 new_fm->e[i]->pnum);
1336                         goto out_kfree;
1337                 }
1338         }
1339
1340         ubi_assert(new_fm);
1341         ubi->fm = new_fm;
1342
1343         ret = self_check_seen(ubi, seen_pebs);
1344         dbg_bld("fastmap written!");
1345
1346 out_kfree:
1347         ubi_free_vid_hdr(ubi, avhdr);
1348         ubi_free_vid_hdr(ubi, dvhdr);
1349         free_seen(seen_pebs);
1350 out:
1351         return ret;
1352 }
1353
1354 /**
1355  * erase_block - Manually erase a PEB.
1356  * @ubi: UBI device object
1357  * @pnum: PEB to be erased
1358  *
1359  * Returns the new EC value on success, < 0 indicates an internal error.
1360  */
1361 static int erase_block(struct ubi_device *ubi, int pnum)
1362 {
1363         int ret;
1364         struct ubi_ec_hdr *ec_hdr;
1365         long long ec;
1366
1367         ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
1368         if (!ec_hdr)
1369                 return -ENOMEM;
1370
1371         ret = ubi_io_read_ec_hdr(ubi, pnum, ec_hdr, 0);
1372         if (ret < 0)
1373                 goto out;
1374         else if (ret && ret != UBI_IO_BITFLIPS) {
1375                 ret = -EINVAL;
1376                 goto out;
1377         }
1378
1379         ret = ubi_io_sync_erase(ubi, pnum, 0);
1380         if (ret < 0)
1381                 goto out;
1382
1383         ec = be64_to_cpu(ec_hdr->ec);
1384         ec += ret;
1385         if (ec > UBI_MAX_ERASECOUNTER) {
1386                 ret = -EINVAL;
1387                 goto out;
1388         }
1389
1390         ec_hdr->ec = cpu_to_be64(ec);
1391         ret = ubi_io_write_ec_hdr(ubi, pnum, ec_hdr);
1392         if (ret < 0)
1393                 goto out;
1394
1395         ret = ec;
1396 out:
1397         kfree(ec_hdr);
1398         return ret;
1399 }
1400
1401 /**
1402  * invalidate_fastmap - destroys a fastmap.
1403  * @ubi: UBI device object
1404  *
1405  * This function ensures that upon next UBI attach a full scan
1406  * is issued. We need this if UBI is about to write a new fastmap
1407  * but is unable to do so. In this case we have two options:
1408  * a) Make sure that the current fastmap will not be usued upon
1409  * attach time and contine or b) fall back to RO mode to have the
1410  * current fastmap in a valid state.
1411  * Returns 0 on success, < 0 indicates an internal error.
1412  */
1413 static int invalidate_fastmap(struct ubi_device *ubi)
1414 {
1415         int ret;
1416         struct ubi_fastmap_layout *fm;
1417         struct ubi_wl_entry *e;
1418         struct ubi_vid_hdr *vh = NULL;
1419
1420         if (!ubi->fm)
1421                 return 0;
1422
1423         ubi->fm = NULL;
1424
1425         ret = -ENOMEM;
1426         fm = kzalloc(sizeof(*fm), GFP_KERNEL);
1427         if (!fm)
1428                 goto out;
1429
1430         vh = new_fm_vhdr(ubi, UBI_FM_SB_VOLUME_ID);
1431         if (!vh)
1432                 goto out_free_fm;
1433
1434         ret = -ENOSPC;
1435         e = ubi_wl_get_fm_peb(ubi, 1);
1436         if (!e)
1437                 goto out_free_fm;
1438
1439         /*
1440          * Create fake fastmap such that UBI will fall back
1441          * to scanning mode.
1442          */
1443         vh->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));
1444         ret = ubi_io_write_vid_hdr(ubi, e->pnum, vh);
1445         if (ret < 0) {
1446                 ubi_wl_put_fm_peb(ubi, e, 0, 0);
1447                 goto out_free_fm;
1448         }
1449
1450         fm->used_blocks = 1;
1451         fm->e[0] = e;
1452
1453         ubi->fm = fm;
1454
1455 out:
1456         ubi_free_vid_hdr(ubi, vh);
1457         return ret;
1458
1459 out_free_fm:
1460         kfree(fm);
1461         goto out;
1462 }
1463
1464 /**
1465  * return_fm_pebs - returns all PEBs used by a fastmap back to the
1466  * WL sub-system.
1467  * @ubi: UBI device object
1468  * @fm: fastmap layout object
1469  */
1470 static void return_fm_pebs(struct ubi_device *ubi,
1471                            struct ubi_fastmap_layout *fm)
1472 {
1473         int i;
1474
1475         if (!fm)
1476                 return;
1477
1478         for (i = 0; i < fm->used_blocks; i++) {
1479                 if (fm->e[i]) {
1480                         ubi_wl_put_fm_peb(ubi, fm->e[i], i,
1481                                           fm->to_be_tortured[i]);
1482                         fm->e[i] = NULL;
1483                 }
1484         }
1485 }
1486
1487 /**
1488  * ubi_update_fastmap - will be called by UBI if a volume changes or
1489  * a fastmap pool becomes full.
1490  * @ubi: UBI device object
1491  *
1492  * Returns 0 on success, < 0 indicates an internal error.
1493  */
1494 int ubi_update_fastmap(struct ubi_device *ubi)
1495 {
1496         int ret, i, j;
1497         struct ubi_fastmap_layout *new_fm, *old_fm;
1498         struct ubi_wl_entry *tmp_e;
1499
1500         down_write(&ubi->fm_protect);
1501
1502         ubi_refill_pools(ubi);
1503
1504         if (ubi->ro_mode || ubi->fm_disabled) {
1505                 up_write(&ubi->fm_protect);
1506                 return 0;
1507         }
1508
1509         ret = ubi_ensure_anchor_pebs(ubi);
1510         if (ret) {
1511                 up_write(&ubi->fm_protect);
1512                 return ret;
1513         }
1514
1515         new_fm = kzalloc(sizeof(*new_fm), GFP_KERNEL);
1516         if (!new_fm) {
1517                 up_write(&ubi->fm_protect);
1518                 return -ENOMEM;
1519         }
1520
1521         new_fm->used_blocks = ubi->fm_size / ubi->leb_size;
1522         old_fm = ubi->fm;
1523         ubi->fm = NULL;
1524
1525         if (new_fm->used_blocks > UBI_FM_MAX_BLOCKS) {
1526                 ubi_err(ubi, "fastmap too large");
1527                 ret = -ENOSPC;
1528                 goto err;
1529         }
1530
1531         for (i = 1; i < new_fm->used_blocks; i++) {
1532                 spin_lock(&ubi->wl_lock);
1533                 tmp_e = ubi_wl_get_fm_peb(ubi, 0);
1534                 spin_unlock(&ubi->wl_lock);
1535
1536                 if (!tmp_e) {
1537                         if (old_fm && old_fm->e[i]) {
1538                                 ret = erase_block(ubi, old_fm->e[i]->pnum);
1539                                 if (ret < 0) {
1540                                         ubi_err(ubi, "could not erase old fastmap PEB");
1541
1542                                         for (j = 1; j < i; j++) {
1543                                                 ubi_wl_put_fm_peb(ubi, new_fm->e[j],
1544                                                                   j, 0);
1545                                                 new_fm->e[j] = NULL;
1546                                         }
1547                                         goto err;
1548                                 }
1549                                 new_fm->e[i] = old_fm->e[i];
1550                                 old_fm->e[i] = NULL;
1551                         } else {
1552                                 ubi_err(ubi, "could not get any free erase block");
1553
1554                                 for (j = 1; j < i; j++) {
1555                                         ubi_wl_put_fm_peb(ubi, new_fm->e[j], j, 0);
1556                                         new_fm->e[j] = NULL;
1557                                 }
1558
1559                                 ret = -ENOSPC;
1560                                 goto err;
1561                         }
1562                 } else {
1563                         new_fm->e[i] = tmp_e;
1564
1565                         if (old_fm && old_fm->e[i]) {
1566                                 ubi_wl_put_fm_peb(ubi, old_fm->e[i], i,
1567                                                   old_fm->to_be_tortured[i]);
1568                                 old_fm->e[i] = NULL;
1569                         }
1570                 }
1571         }
1572
1573         /* Old fastmap is larger than the new one */
1574         if (old_fm && new_fm->used_blocks < old_fm->used_blocks) {
1575                 for (i = new_fm->used_blocks; i < old_fm->used_blocks; i++) {
1576                         ubi_wl_put_fm_peb(ubi, old_fm->e[i], i,
1577                                           old_fm->to_be_tortured[i]);
1578                         old_fm->e[i] = NULL;
1579                 }
1580         }
1581
1582         spin_lock(&ubi->wl_lock);
1583         tmp_e = ubi_wl_get_fm_peb(ubi, 1);
1584         spin_unlock(&ubi->wl_lock);
1585
1586         if (old_fm) {
1587                 /* no fresh anchor PEB was found, reuse the old one */
1588                 if (!tmp_e) {
1589                         ret = erase_block(ubi, old_fm->e[0]->pnum);
1590                         if (ret < 0) {
1591                                 ubi_err(ubi, "could not erase old anchor PEB");
1592
1593                                 for (i = 1; i < new_fm->used_blocks; i++) {
1594                                         ubi_wl_put_fm_peb(ubi, new_fm->e[i],
1595                                                           i, 0);
1596                                         new_fm->e[i] = NULL;
1597                                 }
1598                                 goto err;
1599                         }
1600                         new_fm->e[0] = old_fm->e[0];
1601                         new_fm->e[0]->ec = ret;
1602                         old_fm->e[0] = NULL;
1603                 } else {
1604                         /* we've got a new anchor PEB, return the old one */
1605                         ubi_wl_put_fm_peb(ubi, old_fm->e[0], 0,
1606                                           old_fm->to_be_tortured[0]);
1607                         new_fm->e[0] = tmp_e;
1608                         old_fm->e[0] = NULL;
1609                 }
1610         } else {
1611                 if (!tmp_e) {
1612                         ubi_err(ubi, "could not find any anchor PEB");
1613
1614                         for (i = 1; i < new_fm->used_blocks; i++) {
1615                                 ubi_wl_put_fm_peb(ubi, new_fm->e[i], i, 0);
1616                                 new_fm->e[i] = NULL;
1617                         }
1618
1619                         ret = -ENOSPC;
1620                         goto err;
1621                 }
1622                 new_fm->e[0] = tmp_e;
1623         }
1624
1625         down_write(&ubi->work_sem);
1626         down_write(&ubi->fm_eba_sem);
1627         ret = ubi_write_fastmap(ubi, new_fm);
1628         up_write(&ubi->fm_eba_sem);
1629         up_write(&ubi->work_sem);
1630
1631         if (ret)
1632                 goto err;
1633
1634 out_unlock:
1635         up_write(&ubi->fm_protect);
1636         kfree(old_fm);
1637         return ret;
1638
1639 err:
1640         ubi_warn(ubi, "Unable to write new fastmap, err=%i", ret);
1641
1642         ret = invalidate_fastmap(ubi);
1643         if (ret < 0) {
1644                 ubi_err(ubi, "Unable to invalidiate current fastmap!");
1645                 ubi_ro_mode(ubi);
1646         } else {
1647                 return_fm_pebs(ubi, old_fm);
1648                 return_fm_pebs(ubi, new_fm);
1649                 ret = 0;
1650         }
1651
1652         kfree(new_fm);
1653         goto out_unlock;
1654 }