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

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