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