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 <[email protected]>
   6  *
   7  */
   8
   9 #ifndef __UBOOT__
  10 #include <log.h>
  11 #include <dm/devres.h>
  12 #include <linux/crc32.h>
  13 #include <linux/err.h>
  14 #include <u-boot/crc.h>
  15 #else
  16 #include <div64.h>
  17 #include <malloc.h>
  18 #include <ubi_uboot.h>
  19 #include <linux/bug.h>
  20 #endif
  21
  22 #include <linux/compat.h>
  23 #include <linux/math64.h>
  24 #include "ubi.h"
  25
  26 /**
  27  * init_seen - allocate memory for used for debugging.
  28  * @ubi: UBI device description object
  29  */
  30 static inline int *init_seen(struct ubi_device *ubi)
  31 {
  32         int *ret;
  33
  34         if (!ubi_dbg_chk_fastmap(ubi))
  35                 return NULL;
  36
  37         ret = kcalloc(ubi->peb_count, sizeof(int), GFP_KERNEL);
  38         if (!ret)
  39                 return ERR_PTR(-ENOMEM);
  40
  41         return ret;
  42 }
  43
  44 /**
  45  * free_seen - free the seen logic integer array.
  46  * @seen: integer array of @ubi->peb_count size
  47  */
  48 static inline void free_seen(int *seen)
  49 {
  50         kfree(seen);
  51 }
  52
  53 /**
  54  * set_seen - mark a PEB as seen.
  55  * @ubi: UBI device description object
  56  * @pnum: The PEB to be makred as seen
  57  * @seen: integer array of @ubi->peb_count size
  58  */
  59 static inline void set_seen(struct ubi_device *ubi, int pnum, int *seen)
  60 {
  61         if (!ubi_dbg_chk_fastmap(ubi) || !seen)
  62                 return;
  63
  64         seen[pnum] = 1;
  65 }
  66
  67 /**
  68  * self_check_seen - check whether all PEB have been seen by fastmap.
  69  * @ubi: UBI device description object
  70  * @seen: integer array of @ubi->peb_count size
  71  */
  72 static int self_check_seen(struct ubi_device *ubi, int *seen)
  73 {
  74         int pnum, ret = 0;
  75
  76         if (!ubi_dbg_chk_fastmap(ubi) || !seen)
  77                 return 0;
  78
  79         for (pnum = 0; pnum < ubi->peb_count; pnum++) {
  80                 if (!seen[pnum] && ubi->lookuptbl[pnum]) {
  81                         ubi_err(ubi, "self-check failed for PEB %d, fastmap didn't see it", pnum);
  82                         ret = -EINVAL;
  83                 }
  84         }
  85
  86         return ret;
  87 }
  88
  89 /**
  90  * ubi_calc_fm_size - calculates the fastmap size in bytes for an UBI device.
  91  * @ubi: UBI device description object
  92  */
  93 size_t ubi_calc_fm_size(struct ubi_device *ubi)
  94 {
  95         size_t size;
  96
  97         size = sizeof(struct ubi_fm_sb) +
  98                 sizeof(struct ubi_fm_hdr) +
  99                 sizeof(struct ubi_fm_scan_pool) +
 100                 sizeof(struct ubi_fm_scan_pool) +
 101                 (ubi->peb_count * sizeof(struct ubi_fm_ec)) +
 102                 (sizeof(struct ubi_fm_eba) +
 103                 (ubi->peb_count * sizeof(__be32))) +
 104                 sizeof(struct ubi_fm_volhdr) * UBI_MAX_VOLUMES;
 105         return roundup(size, ubi->leb_size);
 106 }
 107
 108
 109 /**
 110  * new_fm_vhdr - allocate a new volume header for fastmap usage.
 111  * @ubi: UBI device description object
 112  * @vol_id: the VID of the new header
 113  *
 114  * Returns a new struct ubi_vid_hdr on success.
 115  * NULL indicates out of memory.
 116  */
 117 static struct ubi_vid_hdr *new_fm_vhdr(struct ubi_device *ubi, int vol_id)
 118 {
 119         struct ubi_vid_hdr *new;
 120
 121         new = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL);
 122         if (!new)
 123                 goto out;
 124
 125         new->vol_type = UBI_VID_DYNAMIC;
 126         new->vol_id = cpu_to_be32(vol_id);
 127
 128         /* UBI implementations without fastmap support have to delete the
 129          * fastmap.
 130          */
 131         new->compat = UBI_COMPAT_DELETE;
 132
 133 out:
 134         return new;
 135 }
 136
 137 /**
 138  * add_aeb - create and add a attach erase block to a given list.
 139  * @ai: UBI attach info object
 140  * @list: the target list
 141  * @pnum: PEB number of the new attach erase block
 142  * @ec: erease counter of the new LEB
 143  * @scrub: scrub this PEB after attaching
 144  *
 145  * Returns 0 on success, < 0 indicates an internal error.
 146  */
 147 static int add_aeb(struct ubi_attach_info *ai, struct list_head *list,
 148                    int pnum, int ec, int scrub)
 149 {
 150         struct ubi_ainf_peb *aeb;
 151
 152         aeb = kmem_cache_alloc(ai->aeb_slab_cache, GFP_KERNEL);
 153         if (!aeb)
 154                 return -ENOMEM;
 155
 156         aeb->pnum = pnum;
 157         aeb->ec = ec;
 158         aeb->lnum = -1;
 159         aeb->scrub = scrub;
 160         aeb->copy_flag = aeb->sqnum = 0;
 161
 162         ai->ec_sum += aeb->ec;
 163         ai->ec_count++;
 164
 165         if (ai->max_ec < aeb->ec)
 166                 ai->max_ec = aeb->ec;
 167
 168         if (ai->min_ec > aeb->ec)
 169                 ai->min_ec = aeb->ec;
 170
 171         list_add_tail(&aeb->u.list, list);
 172
 173         return 0;
 174 }
 175
 176 /**
 177  * add_vol - create and add a new volume to ubi_attach_info.
 178  * @ai: ubi_attach_info object
 179  * @vol_id: VID of the new volume
 180  * @used_ebs: number of used EBS
 181  * @data_pad: data padding value of the new volume
 182  * @vol_type: volume type
 183  * @last_eb_bytes: number of bytes in the last LEB
 184  *
 185  * Returns the new struct ubi_ainf_volume on success.
 186  * NULL indicates an error.
 187  */
 188 static struct ubi_ainf_volume *add_vol(struct ubi_attach_info *ai, int vol_id,
 189                                        int used_ebs, int data_pad, u8 vol_type,
 190                                        int last_eb_bytes)
 191 {
 192         struct ubi_ainf_volume *av;
 193         struct rb_node **p = &ai->volumes.rb_node, *parent = NULL;
 194
 195         while (*p) {
 196                 parent = *p;
 197                 av = rb_entry(parent, struct ubi_ainf_volume, rb);
 198
 199                 if (vol_id > av->vol_id)
 200                         p = &(*p)->rb_left;
 201                 else if (vol_id < av->vol_id)
 202                         p = &(*p)->rb_right;
 203                 else
 204                         return ERR_PTR(-EINVAL);
 205         }
 206
 207         av = kmalloc(sizeof(struct ubi_ainf_volume), GFP_KERNEL);
 208         if (!av)
 209                 goto out;
 210
 211         av->highest_lnum = av->leb_count = av->used_ebs = 0;
 212         av->vol_id = vol_id;
 213         av->data_pad = data_pad;
 214         av->last_data_size = last_eb_bytes;
 215         av->compat = 0;
 216         av->vol_type = vol_type;
 217         av->root = RB_ROOT;
 218         if (av->vol_type == UBI_STATIC_VOLUME)
 219                 av->used_ebs = used_ebs;
 220
 221         dbg_bld("found volume (ID %i)", vol_id);
 222
 223         rb_link_node(&av->rb, parent, p);
 224         rb_insert_color(&av->rb, &ai->volumes);
 225
 226 out:
 227         return av;
 228 }
 229
 230 /**
 231  * assign_aeb_to_av - assigns a SEB to a given ainf_volume and removes it
 232  * from it's original list.
 233  * @ai: ubi_attach_info object
 234  * @aeb: the to be assigned SEB
 235  * @av: target scan volume
 236  */
 237 static void assign_aeb_to_av(struct ubi_attach_info *ai,
 238                              struct ubi_ainf_peb *aeb,
 239                              struct ubi_ainf_volume *av)
 240 {
 241         struct ubi_ainf_peb *tmp_aeb;
 242         struct rb_node **p = &ai->volumes.rb_node, *parent = NULL;
 243
 244         p = &av->root.rb_node;
 245         while (*p) {
 246                 parent = *p;
 247
 248                 tmp_aeb = rb_entry(parent, struct ubi_ainf_peb, u.rb);
 249                 if (aeb->lnum != tmp_aeb->lnum) {
 250                         if (aeb->lnum < tmp_aeb->lnum)
 251                                 p = &(*p)->rb_left;
 252                         else
 253                                 p = &(*p)->rb_right;
 254
 255                         continue;
 256                 } else
 257                         break;
 258         }
 259
 260         list_del(&aeb->u.list);
 261         av->leb_count++;
 262
 263         rb_link_node(&aeb->u.rb, parent, p);
 264         rb_insert_color(&aeb->u.rb, &av->root);
 265 }
 266
 267 /**
 268  * update_vol - inserts or updates a LEB which was found a pool.
 269  * @ubi: the UBI device object
 270  * @ai: attach info object
 271  * @av: the volume this LEB belongs to
 272  * @new_vh: the volume header derived from new_aeb
 273  * @new_aeb: the AEB to be examined
 274  *
 275  * Returns 0 on success, < 0 indicates an internal error.
 276  */
 277 static int update_vol(struct ubi_device *ubi, struct ubi_attach_info *ai,
 278                       struct ubi_ainf_volume *av, struct ubi_vid_hdr *new_vh,
 279                       struct ubi_ainf_peb *new_aeb)
 280 {
 281         struct rb_node **p = &av->root.rb_node, *parent = NULL;
 282         struct ubi_ainf_peb *aeb, *victim;
 283         int cmp_res;
 284
 285         while (*p) {
 286                 parent = *p;
 287                 aeb = rb_entry(parent, struct ubi_ainf_peb, u.rb);
 288
 289                 if (be32_to_cpu(new_vh->lnum) != aeb->lnum) {
 290                         if (be32_to_cpu(new_vh->lnum) < aeb->lnum)
 291                                 p = &(*p)->rb_left;
 292                         else
 293                                 p = &(*p)->rb_right;
 294
 295                         continue;
 296                 }
 297
 298                 /* This case can happen if the fastmap gets written
 299                  * because of a volume change (creation, deletion, ..).
 300                  * Then a PEB can be within the persistent EBA and the pool.
 301                  */
 302                 if (aeb->pnum == new_aeb->pnum) {
 303                         ubi_assert(aeb->lnum == new_aeb->lnum);
 304                         kmem_cache_free(ai->aeb_slab_cache, new_aeb);
 305
 306                         return 0;
 307                 }
 308
 309                 cmp_res = ubi_compare_lebs(ubi, aeb, new_aeb->pnum, new_vh);
 310                 if (cmp_res < 0)
 311                         return cmp_res;
 312
 313                 /* new_aeb is newer */
 314                 if (cmp_res & 1) {
 315                         victim = kmem_cache_alloc(ai->aeb_slab_cache,
 316                                 GFP_KERNEL);
 317                         if (!victim)
 318                                 return -ENOMEM;
 319
 320                         victim->ec = aeb->ec;
 321                         victim->pnum = aeb->pnum;
 322                         list_add_tail(&victim->u.list, &ai->erase);
 323
 324                         if (av->highest_lnum == be32_to_cpu(new_vh->lnum))
 325                                 av->last_data_size =
 326                                         be32_to_cpu(new_vh->data_size);
 327
 328                         dbg_bld("vol %i: AEB %i's PEB %i is the newer",
 329                                 av->vol_id, aeb->lnum, new_aeb->pnum);
 330
 331                         aeb->ec = new_aeb->ec;
 332                         aeb->pnum = new_aeb->pnum;
 333                         aeb->copy_flag = new_vh->copy_flag;
 334                         aeb->scrub = new_aeb->scrub;
 335                         kmem_cache_free(ai->aeb_slab_cache, new_aeb);
 336
 337                 /* new_aeb is older */
 338                 } else {
 339                         dbg_bld("vol %i: AEB %i's PEB %i is old, dropping it",
 340                                 av->vol_id, aeb->lnum, new_aeb->pnum);
 341                         list_add_tail(&new_aeb->u.list, &ai->erase);
 342                 }
 343
 344                 return 0;
 345         }
 346         /* This LEB is new, let's add it to the volume */
 347
 348         if (av->highest_lnum <= be32_to_cpu(new_vh->lnum)) {
 349                 av->highest_lnum = be32_to_cpu(new_vh->lnum);
 350                 av->last_data_size = be32_to_cpu(new_vh->data_size);
 351         }
 352
 353         if (av->vol_type == UBI_STATIC_VOLUME)
 354                 av->used_ebs = be32_to_cpu(new_vh->used_ebs);
 355
 356         av->leb_count++;
 357
 358         rb_link_node(&new_aeb->u.rb, parent, p);
 359         rb_insert_color(&new_aeb->u.rb, &av->root);
 360
 361         return 0;
 362 }
 363
 364 /**
 365  * process_pool_aeb - we found a non-empty PEB in a pool.
 366  * @ubi: UBI device object
 367  * @ai: attach info object
 368  * @new_vh: the volume header derived from new_aeb
 369  * @new_aeb: the AEB to be examined
 370  *
 371  * Returns 0 on success, < 0 indicates an internal error.
 372  */
 373 static int process_pool_aeb(struct ubi_device *ubi, struct ubi_attach_info *ai,
 374                             struct ubi_vid_hdr *new_vh,
 375                             struct ubi_ainf_peb *new_aeb)
 376 {
 377         struct ubi_ainf_volume *av, *tmp_av = NULL;
 378         struct rb_node **p = &ai->volumes.rb_node, *parent = NULL;
 379         int found = 0;
 380
 381         if (be32_to_cpu(new_vh->vol_id) == UBI_FM_SB_VOLUME_ID ||
 382                 be32_to_cpu(new_vh->vol_id) == UBI_FM_DATA_VOLUME_ID) {
 383                 kmem_cache_free(ai->aeb_slab_cache, new_aeb);
 384
 385                 return 0;
 386         }
 387
 388         /* Find the volume this SEB belongs to */
 389         while (*p) {
 390                 parent = *p;
 391                 tmp_av = rb_entry(parent, struct ubi_ainf_volume, rb);
 392
 393                 if (be32_to_cpu(new_vh->vol_id) > tmp_av->vol_id)
 394                         p = &(*p)->rb_left;
 395                 else if (be32_to_cpu(new_vh->vol_id) < tmp_av->vol_id)
 396                         p = &(*p)->rb_right;
 397                 else {
 398                         found = 1;
 399                         break;
 400                 }
 401         }
 402
 403         if (found)
 404                 av = tmp_av;
 405         else {
 406                 ubi_err(ubi, "orphaned volume in fastmap pool!");
 407                 kmem_cache_free(ai->aeb_slab_cache, new_aeb);
 408                 return UBI_BAD_FASTMAP;
 409         }
 410
 411         ubi_assert(be32_to_cpu(new_vh->vol_id) == av->vol_id);
 412
 413         return update_vol(ubi, ai, av, new_vh, new_aeb);
 414 }
 415
 416 /**
 417  * unmap_peb - unmap a PEB.
 418  * If fastmap detects a free PEB in the pool it has to check whether
 419  * this PEB has been unmapped after writing the fastmap.
 420  *
 421  * @ai: UBI attach info object
 422  * @pnum: The PEB to be unmapped
 423  */
 424 static void unmap_peb(struct ubi_attach_info *ai, int pnum)
 425 {
 426         struct ubi_ainf_volume *av;
 427         struct rb_node *node, *node2;
 428         struct ubi_ainf_peb *aeb;
 429
 430         for (node = rb_first(&ai->volumes); node; node = rb_next(node)) {
 431                 av = rb_entry(node, struct ubi_ainf_volume, rb);
 432
 433                 for (node2 = rb_first(&av->root); node2;
 434                      node2 = rb_next(node2)) {
 435                         aeb = rb_entry(node2, struct ubi_ainf_peb, u.rb);
 436                         if (aeb->pnum == pnum) {
 437                                 rb_erase(&aeb->u.rb, &av->root);
 438                                 av->leb_count--;
 439                                 kmem_cache_free(ai->aeb_slab_cache, aeb);
 440                                 return;
 441                         }
 442                 }
 443         }
 444 }
 445
 446 /**
 447  * scan_pool - scans a pool for changed (no longer empty PEBs).
 448  * @ubi: UBI device object
 449  * @ai: attach info object
 450  * @pebs: an array of all PEB numbers in the to be scanned pool
 451  * @pool_size: size of the pool (number of entries in @pebs)
 452  * @max_sqnum: pointer to the maximal sequence number
 453  * @free: list of PEBs which are most likely free (and go into @ai->free)
 454  *
 455  * Returns 0 on success, if the pool is unusable UBI_BAD_FASTMAP is returned.
 456  * < 0 indicates an internal error.
 457  */
 458 #ifndef __UBOOT__
 459 static int scan_pool(struct ubi_device *ubi, struct ubi_attach_info *ai,
 460                      __be32 *pebs, int pool_size, unsigned long long *max_sqnum,
 461                      struct list_head *free)
 462 #else
 463 static int scan_pool(struct ubi_device *ubi, struct ubi_attach_info *ai,
 464                      __be32 *pebs, int pool_size, unsigned long long *max_sqnum,
 465                      struct list_head *free)
 466 #endif
 467 {
 468         struct ubi_vid_hdr *vh;
 469         struct ubi_ec_hdr *ech;
 470         struct ubi_ainf_peb *new_aeb;
 471         int i, pnum, err, ret = 0;
 472
 473         ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
 474         if (!ech)
 475                 return -ENOMEM;
 476
 477         vh = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL);
 478         if (!vh) {
 479                 kfree(ech);
 480                 return -ENOMEM;
 481         }
 482
 483         dbg_bld("scanning fastmap pool: size = %i", pool_size);
 484
 485         /*
 486          * Now scan all PEBs in the pool to find changes which have been made
 487          * after the creation of the fastmap
 488          */
 489         for (i = 0; i < pool_size; i++) {
 490                 int scrub = 0;
 491                 int image_seq;
 492
 493                 pnum = be32_to_cpu(pebs[i]);
 494
 495                 if (ubi_io_is_bad(ubi, pnum)) {
 496                         ubi_err(ubi, "bad PEB in fastmap pool!");
 497                         ret = UBI_BAD_FASTMAP;
 498                         goto out;
 499                 }
 500
 501                 err = ubi_io_read_ec_hdr(ubi, pnum, ech, 0);
 502                 if (err && err != UBI_IO_BITFLIPS) {
 503                         ubi_err(ubi, "unable to read EC header! PEB:%i err:%i",
 504                                 pnum, err);
 505                         ret = err > 0 ? UBI_BAD_FASTMAP : err;
 506                         goto out;
 507                 } else if (err == UBI_IO_BITFLIPS)
 508                         scrub = 1;
 509
 510                 /*
 511                  * Older UBI implementations have image_seq set to zero, so
 512                  * we shouldn't fail if image_seq == 0.
 513                  */
 514                 image_seq = be32_to_cpu(ech->image_seq);
 515
 516                 if (image_seq && (image_seq != ubi->image_seq)) {
 517                         ubi_err(ubi, "bad image seq: 0x%x, expected: 0x%x",
 518                                 be32_to_cpu(ech->image_seq), ubi->image_seq);
 519                         ret = UBI_BAD_FASTMAP;
 520                         goto out;
 521                 }
 522
 523                 err = ubi_io_read_vid_hdr(ubi, pnum, vh, 0);
 524                 if (err == UBI_IO_FF || err == UBI_IO_FF_BITFLIPS) {
 525                         unsigned long long ec = be64_to_cpu(ech->ec);
 526                         unmap_peb(ai, pnum);
 527                         dbg_bld("Adding PEB to free: %i", pnum);
 528                         if (err == UBI_IO_FF_BITFLIPS)
 529                                 add_aeb(ai, free, pnum, ec, 1);
 530                         else
 531                                 add_aeb(ai, free, pnum, ec, 0);
 532                         continue;
 533                 } else if (err == 0 || err == UBI_IO_BITFLIPS) {
 534                         dbg_bld("Found non empty PEB:%i in pool", pnum);
 535
 536                         if (err == UBI_IO_BITFLIPS)
 537                                 scrub = 1;
 538
 539                         new_aeb = kmem_cache_alloc(ai->aeb_slab_cache,
 540                                                    GFP_KERNEL);
 541                         if (!new_aeb) {
 542                                 ret = -ENOMEM;
 543                                 goto out;
 544                         }
 545
 546                         new_aeb->ec = be64_to_cpu(ech->ec);
 547                         new_aeb->pnum = pnum;
 548                         new_aeb->lnum = be32_to_cpu(vh->lnum);
 549                         new_aeb->sqnum = be64_to_cpu(vh->sqnum);
 550                         new_aeb->copy_flag = vh->copy_flag;
 551                         new_aeb->scrub = scrub;
 552
 553                         if (*max_sqnum < new_aeb->sqnum)
 554                                 *max_sqnum = new_aeb->sqnum;
 555
 556                         err = process_pool_aeb(ubi, ai, vh, new_aeb);
 557                         if (err) {
 558                                 ret = err > 0 ? UBI_BAD_FASTMAP : err;
 559                                 goto out;
 560                         }
 561                 } else {
 562                         /* We are paranoid and fall back to scanning mode */
 563                         ubi_err(ubi, "fastmap pool PEBs contains damaged PEBs!");
 564                         ret = err > 0 ? UBI_BAD_FASTMAP : err;
 565                         goto out;
 566                 }
 567
 568         }
 569
 570 out:
 571         ubi_free_vid_hdr(ubi, vh);
 572         kfree(ech);
 573         return ret;
 574 }
 575
 576 /**
 577  * count_fastmap_pebs - Counts the PEBs found by fastmap.
 578  * @ai: The UBI attach info object
 579  */
 580 static int count_fastmap_pebs(struct ubi_attach_info *ai)
 581 {
 582         struct ubi_ainf_peb *aeb;
 583         struct ubi_ainf_volume *av;
 584         struct rb_node *rb1, *rb2;
 585         int n = 0;
 586
 587         list_for_each_entry(aeb, &ai->erase, u.list)
 588                 n++;
 589
 590         list_for_each_entry(aeb, &ai->free, u.list)
 591                 n++;
 592
 593          ubi_rb_for_each_entry(rb1, av, &ai->volumes, rb)
 594                 ubi_rb_for_each_entry(rb2, aeb, &av->root, u.rb)
 595                         n++;
 596
 597         return n;
 598 }
 599
 600 /**
 601  * ubi_attach_fastmap - creates ubi_attach_info from a fastmap.
 602  * @ubi: UBI device object
 603  * @ai: UBI attach info object
 604  * @fm: the fastmap to be attached
 605  *
 606  * Returns 0 on success, UBI_BAD_FASTMAP if the found fastmap was unusable.
 607  * < 0 indicates an internal error.
 608  */
 609 static int ubi_attach_fastmap(struct ubi_device *ubi,
 610                               struct ubi_attach_info *ai,
 611                               struct ubi_fastmap_layout *fm)
 612 {
 613         struct list_head used, free;
 614         struct ubi_ainf_volume *av;
 615         struct ubi_ainf_peb *aeb, *tmp_aeb, *_tmp_aeb;
 616         struct ubi_fm_sb *fmsb;
 617         struct ubi_fm_hdr *fmhdr;
 618         struct ubi_fm_scan_pool *fmpl, *fmpl_wl;
 619         struct ubi_fm_ec *fmec;
 620         struct ubi_fm_volhdr *fmvhdr;
 621         struct ubi_fm_eba *fm_eba;
 622         int ret, i, j, pool_size, wl_pool_size;
 623         size_t fm_pos = 0, fm_size = ubi->fm_size;
 624         unsigned long long max_sqnum = 0;
 625         void *fm_raw = ubi->fm_buf;
 626
 627         INIT_LIST_HEAD(&used);
 628         INIT_LIST_HEAD(&free);
 629         ai->min_ec = UBI_MAX_ERASECOUNTER;
 630
 631         fmsb = (struct ubi_fm_sb *)(fm_raw);
 632         ai->max_sqnum = fmsb->sqnum;
 633         fm_pos += sizeof(struct ubi_fm_sb);
 634         if (fm_pos >= fm_size)
 635                 goto fail_bad;
 636
 637         fmhdr = (struct ubi_fm_hdr *)(fm_raw + fm_pos);
 638         fm_pos += sizeof(*fmhdr);
 639         if (fm_pos >= fm_size)
 640                 goto fail_bad;
 641
 642         if (be32_to_cpu(fmhdr->magic) != UBI_FM_HDR_MAGIC) {
 643                 ubi_err(ubi, "bad fastmap header magic: 0x%x, expected: 0x%x",
 644                         be32_to_cpu(fmhdr->magic), UBI_FM_HDR_MAGIC);
 645                 goto fail_bad;
 646         }
 647
 648         fmpl = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
 649         fm_pos += sizeof(*fmpl);
 650         if (fm_pos >= fm_size)
 651                 goto fail_bad;
 652         if (be32_to_cpu(fmpl->magic) != UBI_FM_POOL_MAGIC) {
 653                 ubi_err(ubi, "bad fastmap pool magic: 0x%x, expected: 0x%x",
 654                         be32_to_cpu(fmpl->magic), UBI_FM_POOL_MAGIC);
 655                 goto fail_bad;
 656         }
 657
 658         fmpl_wl = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
 659         fm_pos += sizeof(*fmpl_wl);
 660         if (fm_pos >= fm_size)
 661                 goto fail_bad;
 662         if (be32_to_cpu(fmpl_wl->magic) != UBI_FM_POOL_MAGIC) {
 663                 ubi_err(ubi, "bad fastmap WL pool magic: 0x%x, expected: 0x%x",
 664                         be32_to_cpu(fmpl_wl->magic), UBI_FM_POOL_MAGIC);
 665                 goto fail_bad;
 666         }
 667
 668         pool_size = be16_to_cpu(fmpl->size);
 669         wl_pool_size = be16_to_cpu(fmpl_wl->size);
 670         fm->max_pool_size = be16_to_cpu(fmpl->max_size);
 671         fm->max_wl_pool_size = be16_to_cpu(fmpl_wl->max_size);
 672
 673         if (pool_size > UBI_FM_MAX_POOL_SIZE || pool_size < 0) {
 674                 ubi_err(ubi, "bad pool size: %i", pool_size);
 675                 goto fail_bad;
 676         }
 677
 678         if (wl_pool_size > UBI_FM_MAX_POOL_SIZE || wl_pool_size < 0) {
 679                 ubi_err(ubi, "bad WL pool size: %i", wl_pool_size);
 680                 goto fail_bad;
 681         }
 682
 683
 684         if (fm->max_pool_size > UBI_FM_MAX_POOL_SIZE ||
 685             fm->max_pool_size < 0) {
 686                 ubi_err(ubi, "bad maximal pool size: %i", fm->max_pool_size);
 687                 goto fail_bad;
 688         }
 689
 690         if (fm->max_wl_pool_size > UBI_FM_MAX_POOL_SIZE ||
 691             fm->max_wl_pool_size < 0) {
 692                 ubi_err(ubi, "bad maximal WL pool size: %i",
 693                         fm->max_wl_pool_size);
 694                 goto fail_bad;
 695         }
 696
 697         /* read EC values from free list */
 698         for (i = 0; i < be32_to_cpu(fmhdr->free_peb_count); i++) {
 699                 fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
 700                 fm_pos += sizeof(*fmec);
 701                 if (fm_pos >= fm_size)
 702                         goto fail_bad;
 703
 704                 add_aeb(ai, &ai->free, be32_to_cpu(fmec->pnum),
 705                         be32_to_cpu(fmec->ec), 0);
 706         }
 707
 708         /* read EC values from used list */
 709         for (i = 0; i < be32_to_cpu(fmhdr->used_peb_count); i++) {
 710                 fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
 711                 fm_pos += sizeof(*fmec);
 712                 if (fm_pos >= fm_size)
 713                         goto fail_bad;
 714
 715                 add_aeb(ai, &used, be32_to_cpu(fmec->pnum),
 716                         be32_to_cpu(fmec->ec), 0);
 717         }
 718
 719         /* read EC values from scrub list */
 720         for (i = 0; i < be32_to_cpu(fmhdr->scrub_peb_count); i++) {
 721                 fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
 722                 fm_pos += sizeof(*fmec);
 723                 if (fm_pos >= fm_size)
 724                         goto fail_bad;
 725
 726                 add_aeb(ai, &used, be32_to_cpu(fmec->pnum),
 727                         be32_to_cpu(fmec->ec), 1);
 728         }
 729
 730         /* read EC values from erase list */
 731         for (i = 0; i < be32_to_cpu(fmhdr->erase_peb_count); i++) {
 732                 fmec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
 733                 fm_pos += sizeof(*fmec);
 734                 if (fm_pos >= fm_size)
 735                         goto fail_bad;
 736
 737                 add_aeb(ai, &ai->erase, be32_to_cpu(fmec->pnum),
 738                         be32_to_cpu(fmec->ec), 1);
 739         }
 740
 741         ai->mean_ec = div_u64(ai->ec_sum, ai->ec_count);
 742         ai->bad_peb_count = be32_to_cpu(fmhdr->bad_peb_count);
 743
 744         /* Iterate over all volumes and read their EBA table */
 745         for (i = 0; i < be32_to_cpu(fmhdr->vol_count); i++) {
 746                 fmvhdr = (struct ubi_fm_volhdr *)(fm_raw + fm_pos);
 747                 fm_pos += sizeof(*fmvhdr);
 748                 if (fm_pos >= fm_size)
 749                         goto fail_bad;
 750
 751                 if (be32_to_cpu(fmvhdr->magic) != UBI_FM_VHDR_MAGIC) {
 752                         ubi_err(ubi, "bad fastmap vol header magic: 0x%x, expected: 0x%x",
 753                                 be32_to_cpu(fmvhdr->magic), UBI_FM_VHDR_MAGIC);
 754                         goto fail_bad;
 755                 }
 756
 757                 av = add_vol(ai, be32_to_cpu(fmvhdr->vol_id),
 758                              be32_to_cpu(fmvhdr->used_ebs),
 759                              be32_to_cpu(fmvhdr->data_pad),
 760                              fmvhdr->vol_type,
 761                              be32_to_cpu(fmvhdr->last_eb_bytes));
 762
 763                 if (!av)
 764                         goto fail_bad;
 765                 if (PTR_ERR(av) == -EINVAL) {
 766                         ubi_err(ubi, "volume (ID %i) already exists",
 767                                 fmvhdr->vol_id);
 768                         goto fail_bad;
 769                 }
 770
 771                 ai->vols_found++;
 772                 if (ai->highest_vol_id < be32_to_cpu(fmvhdr->vol_id))
 773                         ai->highest_vol_id = be32_to_cpu(fmvhdr->vol_id);
 774
 775                 fm_eba = (struct ubi_fm_eba *)(fm_raw + fm_pos);
 776                 fm_pos += sizeof(*fm_eba);
 777                 fm_pos += (sizeof(__be32) * be32_to_cpu(fm_eba->reserved_pebs));
 778                 if (fm_pos >= fm_size)
 779                         goto fail_bad;
 780
 781                 if (be32_to_cpu(fm_eba->magic) != UBI_FM_EBA_MAGIC) {
 782                         ubi_err(ubi, "bad fastmap EBA header magic: 0x%x, expected: 0x%x",
 783                                 be32_to_cpu(fm_eba->magic), UBI_FM_EBA_MAGIC);
 784                         goto fail_bad;
 785                 }
 786
 787                 for (j = 0; j < be32_to_cpu(fm_eba->reserved_pebs); j++) {
 788                         int pnum = be32_to_cpu(fm_eba->pnum[j]);
 789
 790                         if ((int)be32_to_cpu(fm_eba->pnum[j]) < 0)
 791                                 continue;
 792
 793                         aeb = NULL;
 794                         list_for_each_entry(tmp_aeb, &used, u.list) {
 795                                 if (tmp_aeb->pnum == pnum) {
 796                                         aeb = tmp_aeb;
 797                                         break;
 798                                 }
 799                         }
 800
 801                         if (!aeb) {
 802                                 ubi_err(ubi, "PEB %i is in EBA but not in used list", pnum);
 803                                 goto fail_bad;
 804                         }
 805
 806                         aeb->lnum = j;
 807
 808                         if (av->highest_lnum <= aeb->lnum)
 809                                 av->highest_lnum = aeb->lnum;
 810
 811                         assign_aeb_to_av(ai, aeb, av);
 812
 813                         dbg_bld("inserting PEB:%i (LEB %i) to vol %i",
 814                                 aeb->pnum, aeb->lnum, av->vol_id);
 815                 }
 816         }
 817
 818         ret = scan_pool(ubi, ai, fmpl->pebs, pool_size, &max_sqnum, &free);
 819         if (ret)
 820                 goto fail;
 821
 822         ret = scan_pool(ubi, ai, fmpl_wl->pebs, wl_pool_size, &max_sqnum, &free);
 823         if (ret)
 824                 goto fail;
 825
 826         if (max_sqnum > ai->max_sqnum)
 827                 ai->max_sqnum = max_sqnum;
 828
 829         list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &free, u.list)
 830                 list_move_tail(&tmp_aeb->u.list, &ai->free);
 831
 832         list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &used, u.list)
 833                 list_move_tail(&tmp_aeb->u.list, &ai->erase);
 834
 835         ubi_assert(list_empty(&free));
 836
 837         /*
 838          * If fastmap is leaking PEBs (must not happen), raise a
 839          * fat warning and fall back to scanning mode.
 840          * We do this here because in ubi_wl_init() it's too late
 841          * and we cannot fall back to scanning.
 842          */
 843 #ifndef __UBOOT__
 844         if (WARN_ON(count_fastmap_pebs(ai) != ubi->peb_count -
 845                     ai->bad_peb_count - fm->used_blocks))
 846                 goto fail_bad;
 847 #else
 848         if (count_fastmap_pebs(ai) != ubi->peb_count -
 849                     ai->bad_peb_count - fm->used_blocks) {
 850                 WARN_ON(1);
 851                 goto fail_bad;
 852         }
 853 #endif
 854
 855         return 0;
 856
 857 fail_bad:
 858         ret = UBI_BAD_FASTMAP;
 859 fail:
 860         list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &used, u.list) {
 861                 list_del(&tmp_aeb->u.list);
 862                 kmem_cache_free(ai->aeb_slab_cache, tmp_aeb);
 863         }
 864         list_for_each_entry_safe(tmp_aeb, _tmp_aeb, &free, u.list) {
 865                 list_del(&tmp_aeb->u.list);
 866                 kmem_cache_free(ai->aeb_slab_cache, tmp_aeb);
 867         }
 868
 869         return ret;
 870 }
 871
 872 /**
 873  * ubi_scan_fastmap - scan the fastmap.
 874  * @ubi: UBI device object
 875  * @ai: UBI attach info to be filled
 876  * @fm_anchor: The fastmap starts at this PEB
 877  *
 878  * Returns 0 on success, UBI_NO_FASTMAP if no fastmap was found,
 879  * UBI_BAD_FASTMAP if one was found but is not usable.
 880  * < 0 indicates an internal error.
 881  */
 882 int ubi_scan_fastmap(struct ubi_device *ubi, struct ubi_attach_info *ai,
 883                      int fm_anchor)
 884 {
 885         struct ubi_fm_sb *fmsb, *fmsb2;
 886         struct ubi_vid_hdr *vh;
 887         struct ubi_ec_hdr *ech;
 888         struct ubi_fastmap_layout *fm;
 889         int i, used_blocks, pnum, ret = 0;
 890         size_t fm_size;
 891         __be32 crc, tmp_crc;
 892         unsigned long long sqnum = 0;
 893
 894         down_write(&ubi->fm_protect);
 895         memset(ubi->fm_buf, 0, ubi->fm_size);
 896
 897         fmsb = kmalloc(sizeof(*fmsb), GFP_KERNEL);
 898         if (!fmsb) {
 899                 ret = -ENOMEM;
 900                 goto out;
 901         }
 902
 903         fm = kzalloc(sizeof(*fm), GFP_KERNEL);
 904         if (!fm) {
 905                 ret = -ENOMEM;
 906                 kfree(fmsb);
 907                 goto out;
 908         }
 909
 910         ret = ubi_io_read(ubi, fmsb, fm_anchor, ubi->leb_start, sizeof(*fmsb));
 911         if (ret && ret != UBI_IO_BITFLIPS)
 912                 goto free_fm_sb;
 913         else if (ret == UBI_IO_BITFLIPS)
 914                 fm->to_be_tortured[0] = 1;
 915
 916         if (be32_to_cpu(fmsb->magic) != UBI_FM_SB_MAGIC) {
 917                 ubi_err(ubi, "bad super block magic: 0x%x, expected: 0x%x",
 918                         be32_to_cpu(fmsb->magic), UBI_FM_SB_MAGIC);
 919                 ret = UBI_BAD_FASTMAP;
 920                 goto free_fm_sb;
 921         }
 922
 923         if (fmsb->version != UBI_FM_FMT_VERSION) {
 924                 ubi_err(ubi, "bad fastmap version: %i, expected: %i",
 925                         fmsb->version, UBI_FM_FMT_VERSION);
 926                 ret = UBI_BAD_FASTMAP;
 927                 goto free_fm_sb;
 928         }
 929
 930         used_blocks = be32_to_cpu(fmsb->used_blocks);
 931         if (used_blocks > UBI_FM_MAX_BLOCKS || used_blocks < 1) {
 932                 ubi_err(ubi, "number of fastmap blocks is invalid: %i",
 933                         used_blocks);
 934                 ret = UBI_BAD_FASTMAP;
 935                 goto free_fm_sb;
 936         }
 937
 938         fm_size = ubi->leb_size * used_blocks;
 939         if (fm_size != ubi->fm_size) {
 940                 ubi_err(ubi, "bad fastmap size: %zi, expected: %zi",
 941                         fm_size, ubi->fm_size);
 942                 ret = UBI_BAD_FASTMAP;
 943                 goto free_fm_sb;
 944         }
 945
 946         ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
 947         if (!ech) {
 948                 ret = -ENOMEM;
 949                 goto free_fm_sb;
 950         }
 951
 952         vh = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL);
 953         if (!vh) {
 954                 ret = -ENOMEM;
 955                 goto free_hdr;
 956         }
 957
 958         for (i = 0; i < used_blocks; i++) {
 959                 int image_seq;
 960
 961                 pnum = be32_to_cpu(fmsb->block_loc[i]);
 962
 963                 if (ubi_io_is_bad(ubi, pnum)) {
 964                         ret = UBI_BAD_FASTMAP;
 965                         goto free_hdr;
 966                 }
 967
 968                 ret = ubi_io_read_ec_hdr(ubi, pnum, ech, 0);
 969                 if (ret && ret != UBI_IO_BITFLIPS) {
 970                         ubi_err(ubi, "unable to read fastmap block# %i EC (PEB: %i)",
 971                                 i, pnum);
 972                         if (ret > 0)
 973                                 ret = UBI_BAD_FASTMAP;
 974                         goto free_hdr;
 975                 } else if (ret == UBI_IO_BITFLIPS)
 976                         fm->to_be_tortured[i] = 1;
 977
 978                 image_seq = be32_to_cpu(ech->image_seq);
 979                 if (!ubi->image_seq)
 980                         ubi->image_seq = image_seq;
 981
 982                 /*
 983                  * Older UBI implementations have image_seq set to zero, so
 984                  * we shouldn't fail if image_seq == 0.
 985                  */
 986                 if (image_seq && (image_seq != ubi->image_seq)) {
 987                         ubi_err(ubi, "wrong image seq:%d instead of %d",
 988                                 be32_to_cpu(ech->image_seq), ubi->image_seq);
 989                         ret = UBI_BAD_FASTMAP;
 990                         goto free_hdr;
 991                 }
 992
 993                 ret = ubi_io_read_vid_hdr(ubi, pnum, vh, 0);
 994                 if (ret && ret != UBI_IO_BITFLIPS) {
 995                         ubi_err(ubi, "unable to read fastmap block# %i (PEB: %i)",
 996                                 i, pnum);
 997                         goto free_hdr;
 998                 }
 999
1000                 if (i == 0) {
1001                         if (be32_to_cpu(vh->vol_id) != UBI_FM_SB_VOLUME_ID) {
1002                                 ubi_err(ubi, "bad fastmap anchor vol_id: 0x%x, expected: 0x%x",
1003                                         be32_to_cpu(vh->vol_id),
1004                                         UBI_FM_SB_VOLUME_ID);
1005                                 ret = UBI_BAD_FASTMAP;
1006                                 goto free_hdr;
1007                         }
1008                 } else {
1009                         if (be32_to_cpu(vh->vol_id) != UBI_FM_DATA_VOLUME_ID) {
1010                                 ubi_err(ubi, "bad fastmap data vol_id: 0x%x, expected: 0x%x",
1011                                         be32_to_cpu(vh->vol_id),
1012                                         UBI_FM_DATA_VOLUME_ID);
1013                                 ret = UBI_BAD_FASTMAP;
1014                                 goto free_hdr;
1015                         }
1016                 }
1017
1018                 if (sqnum < be64_to_cpu(vh->sqnum))
1019                         sqnum = be64_to_cpu(vh->sqnum);
1020
1021                 ret = ubi_io_read(ubi, ubi->fm_buf + (ubi->leb_size * i), pnum,
1022                                   ubi->leb_start, ubi->leb_size);
1023                 if (ret && ret != UBI_IO_BITFLIPS) {
1024                         ubi_err(ubi, "unable to read fastmap block# %i (PEB: %i, "
1025                                 "err: %i)", i, pnum, ret);
1026                         goto free_hdr;
1027                 }
1028         }
1029
1030         kfree(fmsb);
1031         fmsb = NULL;
1032
1033         fmsb2 = (struct ubi_fm_sb *)(ubi->fm_buf);
1034         tmp_crc = be32_to_cpu(fmsb2->data_crc);
1035         fmsb2->data_crc = 0;
1036         crc = crc32(UBI_CRC32_INIT, ubi->fm_buf, fm_size);
1037         if (crc != tmp_crc) {
1038                 ubi_err(ubi, "fastmap data CRC is invalid");
1039                 ubi_err(ubi, "CRC should be: 0x%x, calc: 0x%x",
1040                         tmp_crc, crc);
1041                 ret = UBI_BAD_FASTMAP;
1042                 goto free_hdr;
1043         }
1044
1045         fmsb2->sqnum = sqnum;
1046
1047         fm->used_blocks = used_blocks;
1048
1049         ret = ubi_attach_fastmap(ubi, ai, fm);
1050         if (ret) {
1051                 if (ret > 0)
1052                         ret = UBI_BAD_FASTMAP;
1053                 goto free_hdr;
1054         }
1055
1056         for (i = 0; i < used_blocks; i++) {
1057                 struct ubi_wl_entry *e;
1058
1059                 e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_KERNEL);
1060                 if (!e) {
1061                         while (i--)
1062                                 kfree(fm->e[i]);
1063
1064                         ret = -ENOMEM;
1065                         goto free_hdr;
1066                 }
1067
1068                 e->pnum = be32_to_cpu(fmsb2->block_loc[i]);
1069                 e->ec = be32_to_cpu(fmsb2->block_ec[i]);
1070                 fm->e[i] = e;
1071         }
1072
1073         ubi->fm = fm;
1074         ubi->fm_pool.max_size = ubi->fm->max_pool_size;
1075         ubi->fm_wl_pool.max_size = ubi->fm->max_wl_pool_size;
1076         ubi_msg(ubi, "attached by fastmap");
1077         ubi_msg(ubi, "fastmap pool size: %d", ubi->fm_pool.max_size);
1078         ubi_msg(ubi, "fastmap WL pool size: %d",
1079                 ubi->fm_wl_pool.max_size);
1080         ubi->fm_disabled = 0;
1081
1082         ubi_free_vid_hdr(ubi, vh);
1083         kfree(ech);
1084 out:
1085         up_write(&ubi->fm_protect);
1086         if (ret == UBI_BAD_FASTMAP)
1087                 ubi_err(ubi, "Attach by fastmap failed, doing a full scan!");
1088         return ret;
1089
1090 free_hdr:
1091         ubi_free_vid_hdr(ubi, vh);
1092         kfree(ech);
1093 free_fm_sb:
1094         kfree(fmsb);
1095         kfree(fm);
1096         goto out;
1097 }
1098
1099 /**
1100  * ubi_write_fastmap - writes a fastmap.
1101  * @ubi: UBI device object
1102  * @new_fm: the to be written fastmap
1103  *
1104  * Returns 0 on success, < 0 indicates an internal error.
1105  */
1106 static int ubi_write_fastmap(struct ubi_device *ubi,
1107                              struct ubi_fastmap_layout *new_fm)
1108 {
1109         size_t fm_pos = 0;
1110         void *fm_raw;
1111         struct ubi_fm_sb *fmsb;
1112         struct ubi_fm_hdr *fmh;
1113         struct ubi_fm_scan_pool *fmpl, *fmpl_wl;
1114         struct ubi_fm_ec *fec;
1115         struct ubi_fm_volhdr *fvh;
1116         struct ubi_fm_eba *feba;
1117         struct ubi_wl_entry *wl_e;
1118         struct ubi_volume *vol;
1119         struct ubi_vid_hdr *avhdr, *dvhdr;
1120         struct ubi_work *ubi_wrk;
1121         struct rb_node *tmp_rb;
1122         int ret, i, j, free_peb_count, used_peb_count, vol_count;
1123         int scrub_peb_count, erase_peb_count;
1124         int *seen_pebs = NULL;
1125
1126         fm_raw = ubi->fm_buf;
1127         memset(ubi->fm_buf, 0, ubi->fm_size);
1128
1129         avhdr = new_fm_vhdr(ubi, UBI_FM_SB_VOLUME_ID);
1130         if (!avhdr) {
1131                 ret = -ENOMEM;
1132                 goto out;
1133         }
1134
1135         dvhdr = new_fm_vhdr(ubi, UBI_FM_DATA_VOLUME_ID);
1136         if (!dvhdr) {
1137                 ret = -ENOMEM;
1138                 goto out_kfree;
1139         }
1140
1141         seen_pebs = init_seen(ubi);
1142         if (IS_ERR(seen_pebs)) {
1143                 ret = PTR_ERR(seen_pebs);
1144                 goto out_kfree;
1145         }
1146
1147         spin_lock(&ubi->volumes_lock);
1148         spin_lock(&ubi->wl_lock);
1149
1150         fmsb = (struct ubi_fm_sb *)fm_raw;
1151         fm_pos += sizeof(*fmsb);
1152         ubi_assert(fm_pos <= ubi->fm_size);
1153
1154         fmh = (struct ubi_fm_hdr *)(fm_raw + fm_pos);
1155         fm_pos += sizeof(*fmh);
1156         ubi_assert(fm_pos <= ubi->fm_size);
1157
1158         fmsb->magic = cpu_to_be32(UBI_FM_SB_MAGIC);
1159         fmsb->version = UBI_FM_FMT_VERSION;
1160         fmsb->used_blocks = cpu_to_be32(new_fm->used_blocks);
1161         /* the max sqnum will be filled in while *reading* the fastmap */
1162         fmsb->sqnum = 0;
1163
1164         fmh->magic = cpu_to_be32(UBI_FM_HDR_MAGIC);
1165         free_peb_count = 0;
1166         used_peb_count = 0;
1167         scrub_peb_count = 0;
1168         erase_peb_count = 0;
1169         vol_count = 0;
1170
1171         fmpl = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
1172         fm_pos += sizeof(*fmpl);
1173         fmpl->magic = cpu_to_be32(UBI_FM_POOL_MAGIC);
1174         fmpl->size = cpu_to_be16(ubi->fm_pool.size);
1175         fmpl->max_size = cpu_to_be16(ubi->fm_pool.max_size);
1176
1177         for (i = 0; i < ubi->fm_pool.size; i++) {
1178                 fmpl->pebs[i] = cpu_to_be32(ubi->fm_pool.pebs[i]);
1179                 set_seen(ubi, ubi->fm_pool.pebs[i], seen_pebs);
1180         }
1181
1182         fmpl_wl = (struct ubi_fm_scan_pool *)(fm_raw + fm_pos);
1183         fm_pos += sizeof(*fmpl_wl);
1184         fmpl_wl->magic = cpu_to_be32(UBI_FM_POOL_MAGIC);
1185         fmpl_wl->size = cpu_to_be16(ubi->fm_wl_pool.size);
1186         fmpl_wl->max_size = cpu_to_be16(ubi->fm_wl_pool.max_size);
1187
1188         for (i = 0; i < ubi->fm_wl_pool.size; i++) {
1189                 fmpl_wl->pebs[i] = cpu_to_be32(ubi->fm_wl_pool.pebs[i]);
1190                 set_seen(ubi, ubi->fm_wl_pool.pebs[i], seen_pebs);
1191         }
1192
1193         ubi_for_each_free_peb(ubi, wl_e, tmp_rb) {
1194                 fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1195
1196                 fec->pnum = cpu_to_be32(wl_e->pnum);
1197                 set_seen(ubi, wl_e->pnum, seen_pebs);
1198                 fec->ec = cpu_to_be32(wl_e->ec);
1199
1200                 free_peb_count++;
1201                 fm_pos += sizeof(*fec);
1202                 ubi_assert(fm_pos <= ubi->fm_size);
1203         }
1204         fmh->free_peb_count = cpu_to_be32(free_peb_count);
1205
1206         ubi_for_each_used_peb(ubi, wl_e, tmp_rb) {
1207                 fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1208
1209                 fec->pnum = cpu_to_be32(wl_e->pnum);
1210                 set_seen(ubi, wl_e->pnum, seen_pebs);
1211                 fec->ec = cpu_to_be32(wl_e->ec);
1212
1213                 used_peb_count++;
1214                 fm_pos += sizeof(*fec);
1215                 ubi_assert(fm_pos <= ubi->fm_size);
1216         }
1217
1218         ubi_for_each_protected_peb(ubi, i, wl_e) {
1219                 fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1220
1221                 fec->pnum = cpu_to_be32(wl_e->pnum);
1222                 set_seen(ubi, wl_e->pnum, seen_pebs);
1223                 fec->ec = cpu_to_be32(wl_e->ec);
1224
1225                 used_peb_count++;
1226                 fm_pos += sizeof(*fec);
1227                 ubi_assert(fm_pos <= ubi->fm_size);
1228         }
1229         fmh->used_peb_count = cpu_to_be32(used_peb_count);
1230
1231         ubi_for_each_scrub_peb(ubi, wl_e, tmp_rb) {
1232                 fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1233
1234                 fec->pnum = cpu_to_be32(wl_e->pnum);
1235                 set_seen(ubi, wl_e->pnum, seen_pebs);
1236                 fec->ec = cpu_to_be32(wl_e->ec);
1237
1238                 scrub_peb_count++;
1239                 fm_pos += sizeof(*fec);
1240                 ubi_assert(fm_pos <= ubi->fm_size);
1241         }
1242         fmh->scrub_peb_count = cpu_to_be32(scrub_peb_count);
1243
1244
1245         list_for_each_entry(ubi_wrk, &ubi->works, list) {
1246                 if (ubi_is_erase_work(ubi_wrk)) {
1247                         wl_e = ubi_wrk->e;
1248                         ubi_assert(wl_e);
1249
1250                         fec = (struct ubi_fm_ec *)(fm_raw + fm_pos);
1251
1252                         fec->pnum = cpu_to_be32(wl_e->pnum);
1253                         set_seen(ubi, wl_e->pnum, seen_pebs);
1254                         fec->ec = cpu_to_be32(wl_e->ec);
1255
1256                         erase_peb_count++;
1257                         fm_pos += sizeof(*fec);
1258                         ubi_assert(fm_pos <= ubi->fm_size);
1259                 }
1260         }
1261         fmh->erase_peb_count = cpu_to_be32(erase_peb_count);
1262
1263         for (i = 0; i < UBI_MAX_VOLUMES + UBI_INT_VOL_COUNT; i++) {
1264                 vol = ubi->volumes[i];
1265
1266                 if (!vol)
1267                         continue;
1268
1269                 vol_count++;
1270
1271                 fvh = (struct ubi_fm_volhdr *)(fm_raw + fm_pos);
1272                 fm_pos += sizeof(*fvh);
1273                 ubi_assert(fm_pos <= ubi->fm_size);
1274
1275                 fvh->magic = cpu_to_be32(UBI_FM_VHDR_MAGIC);
1276                 fvh->vol_id = cpu_to_be32(vol->vol_id);
1277                 fvh->vol_type = vol->vol_type;
1278                 fvh->used_ebs = cpu_to_be32(vol->used_ebs);
1279                 fvh->data_pad = cpu_to_be32(vol->data_pad);
1280                 fvh->last_eb_bytes = cpu_to_be32(vol->last_eb_bytes);
1281
1282                 ubi_assert(vol->vol_type == UBI_DYNAMIC_VOLUME ||
1283                         vol->vol_type == UBI_STATIC_VOLUME);
1284
1285                 feba = (struct ubi_fm_eba *)(fm_raw + fm_pos);
1286                 fm_pos += sizeof(*feba) + (sizeof(__be32) * vol->reserved_pebs);
1287                 ubi_assert(fm_pos <= ubi->fm_size);
1288
1289                 for (j = 0; j < vol->reserved_pebs; j++)
1290                         feba->pnum[j] = cpu_to_be32(vol->eba_tbl[j]);
1291
1292                 feba->reserved_pebs = cpu_to_be32(j);
1293                 feba->magic = cpu_to_be32(UBI_FM_EBA_MAGIC);
1294         }
1295         fmh->vol_count = cpu_to_be32(vol_count);
1296         fmh->bad_peb_count = cpu_to_be32(ubi->bad_peb_count);
1297
1298         avhdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));
1299         avhdr->lnum = 0;
1300
1301         spin_unlock(&ubi->wl_lock);
1302         spin_unlock(&ubi->volumes_lock);
1303
1304         dbg_bld("writing fastmap SB to PEB %i", new_fm->e[0]->pnum);
1305         ret = ubi_io_write_vid_hdr(ubi, new_fm->e[0]->pnum, avhdr);
1306         if (ret) {
1307                 ubi_err(ubi, "unable to write vid_hdr to fastmap SB!");
1308                 goto out_kfree;
1309         }
1310
1311         for (i = 0; i < new_fm->used_blocks; i++) {
1312                 fmsb->block_loc[i] = cpu_to_be32(new_fm->e[i]->pnum);
1313                 set_seen(ubi, new_fm->e[i]->pnum, seen_pebs);
1314                 fmsb->block_ec[i] = cpu_to_be32(new_fm->e[i]->ec);
1315         }
1316
1317         fmsb->data_crc = 0;
1318         fmsb->data_crc = cpu_to_be32(crc32(UBI_CRC32_INIT, fm_raw,
1319                                            ubi->fm_size));
1320
1321         for (i = 1; i < new_fm->used_blocks; i++) {
1322                 dvhdr->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));
1323                 dvhdr->lnum = cpu_to_be32(i);
1324                 dbg_bld("writing fastmap data to PEB %i sqnum %llu",
1325                         new_fm->e[i]->pnum, be64_to_cpu(dvhdr->sqnum));
1326                 ret = ubi_io_write_vid_hdr(ubi, new_fm->e[i]->pnum, dvhdr);
1327                 if (ret) {
1328                         ubi_err(ubi, "unable to write vid_hdr to PEB %i!",
1329                                 new_fm->e[i]->pnum);
1330                         goto out_kfree;
1331                 }
1332         }
1333
1334         for (i = 0; i < new_fm->used_blocks; i++) {
1335                 ret = ubi_io_write(ubi, fm_raw + (i * ubi->leb_size),
1336                         new_fm->e[i]->pnum, ubi->leb_start, ubi->leb_size);
1337                 if (ret) {
1338                         ubi_err(ubi, "unable to write fastmap to PEB %i!",
1339                                 new_fm->e[i]->pnum);
1340                         goto out_kfree;
1341                 }
1342         }
1343
1344         ubi_assert(new_fm);
1345         ubi->fm = new_fm;
1346
1347         ret = self_check_seen(ubi, seen_pebs);
1348         dbg_bld("fastmap written!");
1349
1350 out_kfree:
1351         ubi_free_vid_hdr(ubi, avhdr);
1352         ubi_free_vid_hdr(ubi, dvhdr);
1353         free_seen(seen_pebs);
1354 out:
1355         return ret;
1356 }
1357
1358 /**
1359  * erase_block - Manually erase a PEB.
1360  * @ubi: UBI device object
1361  * @pnum: PEB to be erased
1362  *
1363  * Returns the new EC value on success, < 0 indicates an internal error.
1364  */
1365 static int erase_block(struct ubi_device *ubi, int pnum)
1366 {
1367         int ret;
1368         struct ubi_ec_hdr *ec_hdr;
1369         long long ec;
1370
1371         ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
1372         if (!ec_hdr)
1373                 return -ENOMEM;
1374
1375         ret = ubi_io_read_ec_hdr(ubi, pnum, ec_hdr, 0);
1376         if (ret < 0)
1377                 goto out;
1378         else if (ret && ret != UBI_IO_BITFLIPS) {
1379                 ret = -EINVAL;
1380                 goto out;
1381         }
1382
1383         ret = ubi_io_sync_erase(ubi, pnum, 0);
1384         if (ret < 0)
1385                 goto out;
1386
1387         ec = be64_to_cpu(ec_hdr->ec);
1388         ec += ret;
1389         if (ec > UBI_MAX_ERASECOUNTER) {
1390                 ret = -EINVAL;
1391                 goto out;
1392         }
1393
1394         ec_hdr->ec = cpu_to_be64(ec);
1395         ret = ubi_io_write_ec_hdr(ubi, pnum, ec_hdr);
1396         if (ret < 0)
1397                 goto out;
1398
1399         ret = ec;
1400 out:
1401         kfree(ec_hdr);
1402         return ret;
1403 }
1404
1405 /**
1406  * invalidate_fastmap - destroys a fastmap.
1407  * @ubi: UBI device object
1408  *
1409  * This function ensures that upon next UBI attach a full scan
1410  * is issued. We need this if UBI is about to write a new fastmap
1411  * but is unable to do so. In this case we have two options:
1412  * a) Make sure that the current fastmap will not be usued upon
1413  * attach time and contine or b) fall back to RO mode to have the
1414  * current fastmap in a valid state.
1415  * Returns 0 on success, < 0 indicates an internal error.
1416  */
1417 static int invalidate_fastmap(struct ubi_device *ubi)
1418 {
1419         int ret;
1420         struct ubi_fastmap_layout *fm;
1421         struct ubi_wl_entry *e;
1422         struct ubi_vid_hdr *vh = NULL;
1423
1424         if (!ubi->fm)
1425                 return 0;
1426
1427         ubi->fm = NULL;
1428
1429         ret = -ENOMEM;
1430         fm = kzalloc(sizeof(*fm), GFP_KERNEL);
1431         if (!fm)
1432                 goto out;
1433
1434         vh = new_fm_vhdr(ubi, UBI_FM_SB_VOLUME_ID);
1435         if (!vh)
1436                 goto out_free_fm;
1437
1438         ret = -ENOSPC;
1439         e = ubi_wl_get_fm_peb(ubi, 1);
1440         if (!e)
1441                 goto out_free_fm;
1442
1443         /*
1444          * Create fake fastmap such that UBI will fall back
1445          * to scanning mode.
1446          */
1447         vh->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));
1448         ret = ubi_io_write_vid_hdr(ubi, e->pnum, vh);
1449         if (ret < 0) {
1450                 ubi_wl_put_fm_peb(ubi, e, 0, 0);
1451                 goto out_free_fm;
1452         }
1453
1454         fm->used_blocks = 1;
1455         fm->e[0] = e;
1456
1457         ubi->fm = fm;
1458
1459 out:
1460         ubi_free_vid_hdr(ubi, vh);
1461         return ret;
1462
1463 out_free_fm:
1464         kfree(fm);
1465         goto out;
1466 }
1467
1468 /**
1469  * return_fm_pebs - returns all PEBs used by a fastmap back to the
1470  * WL sub-system.
1471  * @ubi: UBI device object
1472  * @fm: fastmap layout object
1473  */
1474 static void return_fm_pebs(struct ubi_device *ubi,
1475                            struct ubi_fastmap_layout *fm)
1476 {
1477         int i;
1478
1479         if (!fm)
1480                 return;
1481
1482         for (i = 0; i < fm->used_blocks; i++) {
1483                 if (fm->e[i]) {
1484                         ubi_wl_put_fm_peb(ubi, fm->e[i], i,
1485                                           fm->to_be_tortured[i]);
1486                         fm->e[i] = NULL;
1487                 }
1488         }
1489 }
1490
1491 /**
1492  * ubi_update_fastmap - will be called by UBI if a volume changes or
1493  * a fastmap pool becomes full.
1494  * @ubi: UBI device object
1495  *
1496  * Returns 0 on success, < 0 indicates an internal error.
1497  */
1498 int ubi_update_fastmap(struct ubi_device *ubi)
1499 {
1500         int ret, i, j;
1501         struct ubi_fastmap_layout *new_fm, *old_fm;
1502         struct ubi_wl_entry *tmp_e;
1503
1504         down_write(&ubi->fm_protect);
1505
1506         ubi_refill_pools(ubi);
1507
1508         if (ubi->ro_mode || ubi->fm_disabled) {
1509                 up_write(&ubi->fm_protect);
1510                 return 0;
1511         }
1512
1513         ret = ubi_ensure_anchor_pebs(ubi);
1514         if (ret) {
1515                 up_write(&ubi->fm_protect);
1516                 return ret;
1517         }
1518
1519         new_fm = kzalloc(sizeof(*new_fm), GFP_KERNEL);
1520         if (!new_fm) {
1521                 up_write(&ubi->fm_protect);
1522                 return -ENOMEM;
1523         }
1524
1525         new_fm->used_blocks = ubi->fm_size / ubi->leb_size;
1526         old_fm = ubi->fm;
1527         ubi->fm = NULL;
1528
1529         if (new_fm->used_blocks > UBI_FM_MAX_BLOCKS) {
1530                 ubi_err(ubi, "fastmap too large");
1531                 ret = -ENOSPC;
1532                 goto err;
1533         }
1534
1535         for (i = 1; i < new_fm->used_blocks; i++) {
1536                 spin_lock(&ubi->wl_lock);
1537                 tmp_e = ubi_wl_get_fm_peb(ubi, 0);
1538                 spin_unlock(&ubi->wl_lock);
1539
1540                 if (!tmp_e) {
1541                         if (old_fm && old_fm->e[i]) {
1542                                 ret = erase_block(ubi, old_fm->e[i]->pnum);
1543                                 if (ret < 0) {
1544                                         ubi_err(ubi, "could not erase old fastmap PEB");
1545
1546                                         for (j = 1; j < i; j++) {
1547                                                 ubi_wl_put_fm_peb(ubi, new_fm->e[j],
1548                                                                   j, 0);
1549                                                 new_fm->e[j] = NULL;
1550                                         }
1551                                         goto err;
1552                                 }
1553                                 new_fm->e[i] = old_fm->e[i];
1554                                 old_fm->e[i] = NULL;
1555                         } else {
1556                                 ubi_err(ubi, "could not get any free erase block");
1557
1558                                 for (j = 1; j < i; j++) {
1559                                         ubi_wl_put_fm_peb(ubi, new_fm->e[j], j, 0);
1560                                         new_fm->e[j] = NULL;
1561                                 }
1562
1563                                 ret = -ENOSPC;
1564                                 goto err;
1565                         }
1566                 } else {
1567                         new_fm->e[i] = tmp_e;
1568
1569                         if (old_fm && old_fm->e[i]) {
1570                                 ubi_wl_put_fm_peb(ubi, old_fm->e[i], i,
1571                                                   old_fm->to_be_tortured[i]);
1572                                 old_fm->e[i] = NULL;
1573                         }
1574                 }
1575         }
1576
1577         /* Old fastmap is larger than the new one */
1578         if (old_fm && new_fm->used_blocks < old_fm->used_blocks) {
1579                 for (i = new_fm->used_blocks; i < old_fm->used_blocks; i++) {
1580                         ubi_wl_put_fm_peb(ubi, old_fm->e[i], i,
1581                                           old_fm->to_be_tortured[i]);
1582                         old_fm->e[i] = NULL;
1583                 }
1584         }
1585
1586         spin_lock(&ubi->wl_lock);
1587         tmp_e = ubi_wl_get_fm_peb(ubi, 1);
1588         spin_unlock(&ubi->wl_lock);
1589
1590         if (old_fm) {
1591                 /* no fresh anchor PEB was found, reuse the old one */
1592                 if (!tmp_e) {
1593                         ret = erase_block(ubi, old_fm->e[0]->pnum);
1594                         if (ret < 0) {
1595                                 ubi_err(ubi, "could not erase old anchor PEB");
1596
1597                                 for (i = 1; i < new_fm->used_blocks; i++) {
1598                                         ubi_wl_put_fm_peb(ubi, new_fm->e[i],
1599                                                           i, 0);
1600                                         new_fm->e[i] = NULL;
1601                                 }
1602                                 goto err;
1603                         }
1604                         new_fm->e[0] = old_fm->e[0];
1605                         new_fm->e[0]->ec = ret;
1606                         old_fm->e[0] = NULL;
1607                 } else {
1608                         /* we've got a new anchor PEB, return the old one */
1609                         ubi_wl_put_fm_peb(ubi, old_fm->e[0], 0,
1610                                           old_fm->to_be_tortured[0]);
1611                         new_fm->e[0] = tmp_e;
1612                         old_fm->e[0] = NULL;
1613                 }
1614         } else {
1615                 if (!tmp_e) {
1616                         ubi_err(ubi, "could not find any anchor PEB");
1617
1618                         for (i = 1; i < new_fm->used_blocks; i++) {
1619                                 ubi_wl_put_fm_peb(ubi, new_fm->e[i], i, 0);
1620                                 new_fm->e[i] = NULL;
1621                         }
1622
1623                         ret = -ENOSPC;
1624                         goto err;
1625                 }
1626                 new_fm->e[0] = tmp_e;
1627         }
1628
1629         down_write(&ubi->work_sem);
1630         down_write(&ubi->fm_eba_sem);
1631         ret = ubi_write_fastmap(ubi, new_fm);
1632         up_write(&ubi->fm_eba_sem);
1633         up_write(&ubi->work_sem);
1634
1635         if (ret)
1636                 goto err;
1637
1638 out_unlock:
1639         up_write(&ubi->fm_protect);
1640         kfree(old_fm);
1641         return ret;
1642
1643 err:
1644         ubi_warn(ubi, "Unable to write new fastmap, err=%i", ret);
1645
1646         ret = invalidate_fastmap(ubi);
1647         if (ret < 0) {
1648                 ubi_err(ubi, "Unable to invalidiate current fastmap!");
1649                 ubi_ro_mode(ubi);
1650         } else {
1651                 return_fm_pebs(ubi, old_fm);
1652                 return_fm_pebs(ubi, new_fm);
1653                 ret = 0;
1654         }
1655
1656         kfree(new_fm);
1657         goto out_unlock;
1658 }