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attach.c
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1 /*
2  * Copyright (c) International Business Machines Corp., 2006
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation; either version 2 of the License, or
7  * (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
12  * the GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17  *
18  * Author: Artem Bityutskiy (Битюцкий Артём)
19  */
20 
21 /*
22  * UBI attaching sub-system.
23  *
24  * This sub-system is responsible for attaching MTD devices and it also
25  * implements flash media scanning.
26  *
27  * The attaching information is represented by a &struct ubi_attach_info'
28  * object. Information about volumes is represented by &struct ubi_ainf_volume
29  * objects which are kept in volume RB-tree with root at the @volumes field.
30  * The RB-tree is indexed by the volume ID.
31  *
32  * Logical eraseblocks are represented by &struct ubi_ainf_peb objects. These
33  * objects are kept in per-volume RB-trees with the root at the corresponding
34  * &struct ubi_ainf_volume object. To put it differently, we keep an RB-tree of
35  * per-volume objects and each of these objects is the root of RB-tree of
36  * per-LEB objects.
37  *
38  * Corrupted physical eraseblocks are put to the @corr list, free physical
39  * eraseblocks are put to the @free list and the physical eraseblock to be
40  * erased are put to the @erase list.
41  *
42  * About corruptions
43  * ~~~~~~~~~~~~~~~~~
44  *
45  * UBI protects EC and VID headers with CRC-32 checksums, so it can detect
46  * whether the headers are corrupted or not. Sometimes UBI also protects the
47  * data with CRC-32, e.g., when it executes the atomic LEB change operation, or
48  * when it moves the contents of a PEB for wear-leveling purposes.
49  *
50  * UBI tries to distinguish between 2 types of corruptions.
51  *
52  * 1. Corruptions caused by power cuts. These are expected corruptions and UBI
53  * tries to handle them gracefully, without printing too many warnings and
54  * error messages. The idea is that we do not lose important data in these
55  * cases - we may lose only the data which were being written to the media just
56  * before the power cut happened, and the upper layers (e.g., UBIFS) are
57  * supposed to handle such data losses (e.g., by using the FS journal).
58  *
59  * When UBI detects a corruption (CRC-32 mismatch) in a PEB, and it looks like
60  * the reason is a power cut, UBI puts this PEB to the @erase list, and all
61  * PEBs in the @erase list are scheduled for erasure later.
62  *
63  * 2. Unexpected corruptions which are not caused by power cuts. During
64  * attaching, such PEBs are put to the @corr list and UBI preserves them.
65  * Obviously, this lessens the amount of available PEBs, and if at some point
66  * UBI runs out of free PEBs, it switches to R/O mode. UBI also loudly informs
67  * about such PEBs every time the MTD device is attached.
68  *
69  * However, it is difficult to reliably distinguish between these types of
70  * corruptions and UBI's strategy is as follows (in case of attaching by
71  * scanning). UBI assumes corruption type 2 if the VID header is corrupted and
72  * the data area does not contain all 0xFFs, and there were no bit-flips or
73  * integrity errors (e.g., ECC errors in case of NAND) while reading the data
74  * area. Otherwise UBI assumes corruption type 1. So the decision criteria
75  * are as follows.
76  * o If the data area contains only 0xFFs, there are no data, and it is safe
77  * to just erase this PEB - this is corruption type 1.
78  * o If the data area has bit-flips or data integrity errors (ECC errors on
79  * NAND), it is probably a PEB which was being erased when power cut
80  * happened, so this is corruption type 1. However, this is just a guess,
81  * which might be wrong.
82  * o Otherwise this is corruption type 2.
83  */
84 
85 #include <linux/err.h>
86 #include <linux/slab.h>
87 #include <linux/crc32.h>
88 #include <linux/math64.h>
89 #include <linux/random.h>
90 #include "ubi.h"
91 
92 static int self_check_ai(struct ubi_device *ubi, struct ubi_attach_info *ai);
93 
94 /* Temporary variables used during scanning */
95 static struct ubi_ec_hdr *ech;
96 static struct ubi_vid_hdr *vidh;
97 
119 static int add_to_list(struct ubi_attach_info *ai, int pnum, int vol_id,
120  int lnum, int ec, int to_head, struct list_head *list)
121 {
122  struct ubi_ainf_peb *aeb;
123 
124  if (list == &ai->free) {
125  dbg_bld("add to free: PEB %d, EC %d", pnum, ec);
126  } else if (list == &ai->erase) {
127  dbg_bld("add to erase: PEB %d, EC %d", pnum, ec);
128  } else if (list == &ai->alien) {
129  dbg_bld("add to alien: PEB %d, EC %d", pnum, ec);
130  ai->alien_peb_count += 1;
131  } else
132  BUG();
133 
135  if (!aeb)
136  return -ENOMEM;
137 
138  aeb->pnum = pnum;
139  aeb->vol_id = vol_id;
140  aeb->lnum = lnum;
141  aeb->ec = ec;
142  if (to_head)
143  list_add(&aeb->u.list, list);
144  else
145  list_add_tail(&aeb->u.list, list);
146  return 0;
147 }
148 
160 static int add_corrupted(struct ubi_attach_info *ai, int pnum, int ec)
161 {
162  struct ubi_ainf_peb *aeb;
163 
164  dbg_bld("add to corrupted: PEB %d, EC %d", pnum, ec);
165 
167  if (!aeb)
168  return -ENOMEM;
169 
170  ai->corr_peb_count += 1;
171  aeb->pnum = pnum;
172  aeb->ec = ec;
173  list_add(&aeb->u.list, &ai->corr);
174  return 0;
175 }
176 
191 static int validate_vid_hdr(const struct ubi_vid_hdr *vid_hdr,
192  const struct ubi_ainf_volume *av, int pnum)
193 {
194  int vol_type = vid_hdr->vol_type;
195  int vol_id = be32_to_cpu(vid_hdr->vol_id);
196  int used_ebs = be32_to_cpu(vid_hdr->used_ebs);
197  int data_pad = be32_to_cpu(vid_hdr->data_pad);
198 
199  if (av->leb_count != 0) {
200  int av_vol_type;
201 
202  /*
203  * This is not the first logical eraseblock belonging to this
204  * volume. Ensure that the data in its VID header is consistent
205  * to the data in previous logical eraseblock headers.
206  */
207 
208  if (vol_id != av->vol_id) {
209  ubi_err("inconsistent vol_id");
210  goto bad;
211  }
212 
213  if (av->vol_type == UBI_STATIC_VOLUME)
214  av_vol_type = UBI_VID_STATIC;
215  else
216  av_vol_type = UBI_VID_DYNAMIC;
217 
218  if (vol_type != av_vol_type) {
219  ubi_err("inconsistent vol_type");
220  goto bad;
221  }
222 
223  if (used_ebs != av->used_ebs) {
224  ubi_err("inconsistent used_ebs");
225  goto bad;
226  }
227 
228  if (data_pad != av->data_pad) {
229  ubi_err("inconsistent data_pad");
230  goto bad;
231  }
232  }
233 
234  return 0;
235 
236 bad:
237  ubi_err("inconsistent VID header at PEB %d", pnum);
238  ubi_dump_vid_hdr(vid_hdr);
239  ubi_dump_av(av);
240  return -EINVAL;
241 }
242 
256 static struct ubi_ainf_volume *add_volume(struct ubi_attach_info *ai,
257  int vol_id, int pnum,
258  const struct ubi_vid_hdr *vid_hdr)
259 {
260  struct ubi_ainf_volume *av;
261  struct rb_node **p = &ai->volumes.rb_node, *parent = NULL;
262 
263  ubi_assert(vol_id == be32_to_cpu(vid_hdr->vol_id));
264 
265  /* Walk the volume RB-tree to look if this volume is already present */
266  while (*p) {
267  parent = *p;
268  av = rb_entry(parent, struct ubi_ainf_volume, rb);
269 
270  if (vol_id == av->vol_id)
271  return av;
272 
273  if (vol_id > av->vol_id)
274  p = &(*p)->rb_left;
275  else
276  p = &(*p)->rb_right;
277  }
278 
279  /* The volume is absent - add it */
280  av = kmalloc(sizeof(struct ubi_ainf_volume), GFP_KERNEL);
281  if (!av)
282  return ERR_PTR(-ENOMEM);
283 
284  av->highest_lnum = av->leb_count = 0;
285  av->vol_id = vol_id;
286  av->root = RB_ROOT;
287  av->used_ebs = be32_to_cpu(vid_hdr->used_ebs);
288  av->data_pad = be32_to_cpu(vid_hdr->data_pad);
289  av->compat = vid_hdr->compat;
292  if (vol_id > ai->highest_vol_id)
293  ai->highest_vol_id = vol_id;
294 
295  rb_link_node(&av->rb, parent, p);
296  rb_insert_color(&av->rb, &ai->volumes);
297  ai->vols_found += 1;
298  dbg_bld("added volume %d", vol_id);
299  return av;
300 }
301 
322 int ubi_compare_lebs(struct ubi_device *ubi, const struct ubi_ainf_peb *aeb,
323  int pnum, const struct ubi_vid_hdr *vid_hdr)
324 {
325  void *buf;
326  int len, err, second_is_newer, bitflips = 0, corrupted = 0;
328  struct ubi_vid_hdr *vh = NULL;
329  unsigned long long sqnum2 = be64_to_cpu(vid_hdr->sqnum);
330 
331  if (sqnum2 == aeb->sqnum) {
332  /*
333  * This must be a really ancient UBI image which has been
334  * created before sequence numbers support has been added. At
335  * that times we used 32-bit LEB versions stored in logical
336  * eraseblocks. That was before UBI got into mainline. We do not
337  * support these images anymore. Well, those images still work,
338  * but only if no unclean reboots happened.
339  */
340  ubi_err("unsupported on-flash UBI format");
341  return -EINVAL;
342  }
343 
344  /* Obviously the LEB with lower sequence counter is older */
345  second_is_newer = (sqnum2 > aeb->sqnum);
346 
347  /*
348  * Now we know which copy is newer. If the copy flag of the PEB with
349  * newer version is not set, then we just return, otherwise we have to
350  * check data CRC. For the second PEB we already have the VID header,
351  * for the first one - we'll need to re-read it from flash.
352  *
353  * Note: this may be optimized so that we wouldn't read twice.
354  */
355 
356  if (second_is_newer) {
357  if (!vid_hdr->copy_flag) {
358  /* It is not a copy, so it is newer */
359  dbg_bld("second PEB %d is newer, copy_flag is unset",
360  pnum);
361  return 1;
362  }
363  } else {
364  if (!aeb->copy_flag) {
365  /* It is not a copy, so it is newer */
366  dbg_bld("first PEB %d is newer, copy_flag is unset",
367  pnum);
368  return bitflips << 1;
369  }
370 
371  vh = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL);
372  if (!vh)
373  return -ENOMEM;
374 
375  pnum = aeb->pnum;
376  err = ubi_io_read_vid_hdr(ubi, pnum, vh, 0);
377  if (err) {
378  if (err == UBI_IO_BITFLIPS)
379  bitflips = 1;
380  else {
381  ubi_err("VID of PEB %d header is bad, but it was OK earlier, err %d",
382  pnum, err);
383  if (err > 0)
384  err = -EIO;
385 
386  goto out_free_vidh;
387  }
388  }
389 
390  vid_hdr = vh;
391  }
392 
393  /* Read the data of the copy and check the CRC */
394 
395  len = be32_to_cpu(vid_hdr->data_size);
396  buf = vmalloc(len);
397  if (!buf) {
398  err = -ENOMEM;
399  goto out_free_vidh;
400  }
401 
402  err = ubi_io_read_data(ubi, buf, pnum, 0, len);
403  if (err && err != UBI_IO_BITFLIPS && !mtd_is_eccerr(err))
404  goto out_free_buf;
405 
406  data_crc = be32_to_cpu(vid_hdr->data_crc);
407  crc = crc32(UBI_CRC32_INIT, buf, len);
408  if (crc != data_crc) {
409  dbg_bld("PEB %d CRC error: calculated %#08x, must be %#08x",
410  pnum, crc, data_crc);
411  corrupted = 1;
412  bitflips = 0;
413  second_is_newer = !second_is_newer;
414  } else {
415  dbg_bld("PEB %d CRC is OK", pnum);
416  bitflips = !!err;
417  }
418 
419  vfree(buf);
420  ubi_free_vid_hdr(ubi, vh);
421 
422  if (second_is_newer)
423  dbg_bld("second PEB %d is newer, copy_flag is set", pnum);
424  else
425  dbg_bld("first PEB %d is newer, copy_flag is set", pnum);
426 
427  return second_is_newer | (bitflips << 1) | (corrupted << 2);
428 
429 out_free_buf:
430  vfree(buf);
431 out_free_vidh:
432  ubi_free_vid_hdr(ubi, vh);
433  return err;
434 }
435 
452 int ubi_add_to_av(struct ubi_device *ubi, struct ubi_attach_info *ai, int pnum,
453  int ec, const struct ubi_vid_hdr *vid_hdr, int bitflips)
454 {
455  int err, vol_id, lnum;
456  unsigned long long sqnum;
457  struct ubi_ainf_volume *av;
458  struct ubi_ainf_peb *aeb;
459  struct rb_node **p, *parent = NULL;
460 
461  vol_id = be32_to_cpu(vid_hdr->vol_id);
462  lnum = be32_to_cpu(vid_hdr->lnum);
463  sqnum = be64_to_cpu(vid_hdr->sqnum);
464 
465  dbg_bld("PEB %d, LEB %d:%d, EC %d, sqnum %llu, bitflips %d",
466  pnum, vol_id, lnum, ec, sqnum, bitflips);
467 
468  av = add_volume(ai, vol_id, pnum, vid_hdr);
469  if (IS_ERR(av))
470  return PTR_ERR(av);
471 
472  if (ai->max_sqnum < sqnum)
473  ai->max_sqnum = sqnum;
474 
475  /*
476  * Walk the RB-tree of logical eraseblocks of volume @vol_id to look
477  * if this is the first instance of this logical eraseblock or not.
478  */
479  p = &av->root.rb_node;
480  while (*p) {
481  int cmp_res;
482 
483  parent = *p;
484  aeb = rb_entry(parent, struct ubi_ainf_peb, u.rb);
485  if (lnum != aeb->lnum) {
486  if (lnum < aeb->lnum)
487  p = &(*p)->rb_left;
488  else
489  p = &(*p)->rb_right;
490  continue;
491  }
492 
493  /*
494  * There is already a physical eraseblock describing the same
495  * logical eraseblock present.
496  */
497 
498  dbg_bld("this LEB already exists: PEB %d, sqnum %llu, EC %d",
499  aeb->pnum, aeb->sqnum, aeb->ec);
500 
501  /*
502  * Make sure that the logical eraseblocks have different
503  * sequence numbers. Otherwise the image is bad.
504  *
505  * However, if the sequence number is zero, we assume it must
506  * be an ancient UBI image from the era when UBI did not have
507  * sequence numbers. We still can attach these images, unless
508  * there is a need to distinguish between old and new
509  * eraseblocks, in which case we'll refuse the image in
510  * 'ubi_compare_lebs()'. In other words, we attach old clean
511  * images, but refuse attaching old images with duplicated
512  * logical eraseblocks because there was an unclean reboot.
513  */
514  if (aeb->sqnum == sqnum && sqnum != 0) {
515  ubi_err("two LEBs with same sequence number %llu",
516  sqnum);
517  ubi_dump_aeb(aeb, 0);
518  ubi_dump_vid_hdr(vid_hdr);
519  return -EINVAL;
520  }
521 
522  /*
523  * Now we have to drop the older one and preserve the newer
524  * one.
525  */
526  cmp_res = ubi_compare_lebs(ubi, aeb, pnum, vid_hdr);
527  if (cmp_res < 0)
528  return cmp_res;
529 
530  if (cmp_res & 1) {
531  /*
532  * This logical eraseblock is newer than the one
533  * found earlier.
534  */
535  err = validate_vid_hdr(vid_hdr, av, pnum);
536  if (err)
537  return err;
538 
539  err = add_to_list(ai, aeb->pnum, aeb->vol_id,
540  aeb->lnum, aeb->ec, cmp_res & 4,
541  &ai->erase);
542  if (err)
543  return err;
544 
545  aeb->ec = ec;
546  aeb->pnum = pnum;
547  aeb->vol_id = vol_id;
548  aeb->lnum = lnum;
549  aeb->scrub = ((cmp_res & 2) || bitflips);
550  aeb->copy_flag = vid_hdr->copy_flag;
551  aeb->sqnum = sqnum;
552 
553  if (av->highest_lnum == lnum)
554  av->last_data_size =
555  be32_to_cpu(vid_hdr->data_size);
556 
557  return 0;
558  } else {
559  /*
560  * This logical eraseblock is older than the one found
561  * previously.
562  */
563  return add_to_list(ai, pnum, vol_id, lnum, ec,
564  cmp_res & 4, &ai->erase);
565  }
566  }
567 
568  /*
569  * We've met this logical eraseblock for the first time, add it to the
570  * attaching information.
571  */
572 
573  err = validate_vid_hdr(vid_hdr, av, pnum);
574  if (err)
575  return err;
576 
578  if (!aeb)
579  return -ENOMEM;
580 
581  aeb->ec = ec;
582  aeb->pnum = pnum;
583  aeb->vol_id = vol_id;
584  aeb->lnum = lnum;
585  aeb->scrub = bitflips;
586  aeb->copy_flag = vid_hdr->copy_flag;
587  aeb->sqnum = sqnum;
588 
589  if (av->highest_lnum <= lnum) {
590  av->highest_lnum = lnum;
591  av->last_data_size = be32_to_cpu(vid_hdr->data_size);
592  }
593 
594  av->leb_count += 1;
595  rb_link_node(&aeb->u.rb, parent, p);
596  rb_insert_color(&aeb->u.rb, &av->root);
597  return 0;
598 }
599 
608 struct ubi_ainf_volume *ubi_find_av(const struct ubi_attach_info *ai,
609  int vol_id)
610 {
611  struct ubi_ainf_volume *av;
612  struct rb_node *p = ai->volumes.rb_node;
613 
614  while (p) {
615  av = rb_entry(p, struct ubi_ainf_volume, rb);
616 
617  if (vol_id == av->vol_id)
618  return av;
619 
620  if (vol_id > av->vol_id)
621  p = p->rb_left;
622  else
623  p = p->rb_right;
624  }
625 
626  return NULL;
627 }
628 
634 void ubi_remove_av(struct ubi_attach_info *ai, struct ubi_ainf_volume *av)
635 {
636  struct rb_node *rb;
637  struct ubi_ainf_peb *aeb;
638 
639  dbg_bld("remove attaching information about volume %d", av->vol_id);
640 
641  while ((rb = rb_first(&av->root))) {
642  aeb = rb_entry(rb, struct ubi_ainf_peb, u.rb);
643  rb_erase(&aeb->u.rb, &av->root);
644  list_add_tail(&aeb->u.list, &ai->erase);
645  }
646 
647  rb_erase(&av->rb, &ai->volumes);
648  kfree(av);
649  ai->vols_found -= 1;
650 }
651 
665 static int early_erase_peb(struct ubi_device *ubi,
666  const struct ubi_attach_info *ai, int pnum, int ec)
667 {
668  int err;
669  struct ubi_ec_hdr *ec_hdr;
670 
671  if ((long long)ec >= UBI_MAX_ERASECOUNTER) {
672  /*
673  * Erase counter overflow. Upgrade UBI and use 64-bit
674  * erase counters internally.
675  */
676  ubi_err("erase counter overflow at PEB %d, EC %d", pnum, ec);
677  return -EINVAL;
678  }
679 
680  ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
681  if (!ec_hdr)
682  return -ENOMEM;
683 
684  ec_hdr->ec = cpu_to_be64(ec);
685 
686  err = ubi_io_sync_erase(ubi, pnum, 0);
687  if (err < 0)
688  goto out_free;
689 
690  err = ubi_io_write_ec_hdr(ubi, pnum, ec_hdr);
691 
692 out_free:
693  kfree(ec_hdr);
694  return err;
695 }
696 
712  struct ubi_attach_info *ai)
713 {
714  int err = 0;
715  struct ubi_ainf_peb *aeb, *tmp_aeb;
716 
717  if (!list_empty(&ai->free)) {
718  aeb = list_entry(ai->free.next, struct ubi_ainf_peb, u.list);
719  list_del(&aeb->u.list);
720  dbg_bld("return free PEB %d, EC %d", aeb->pnum, aeb->ec);
721  return aeb;
722  }
723 
724  /*
725  * We try to erase the first physical eraseblock from the erase list
726  * and pick it if we succeed, or try to erase the next one if not. And
727  * so forth. We don't want to take care about bad eraseblocks here -
728  * they'll be handled later.
729  */
730  list_for_each_entry_safe(aeb, tmp_aeb, &ai->erase, u.list) {
731  if (aeb->ec == UBI_UNKNOWN)
732  aeb->ec = ai->mean_ec;
733 
734  err = early_erase_peb(ubi, ai, aeb->pnum, aeb->ec+1);
735  if (err)
736  continue;
737 
738  aeb->ec += 1;
739  list_del(&aeb->u.list);
740  dbg_bld("return PEB %d, EC %d", aeb->pnum, aeb->ec);
741  return aeb;
742  }
743 
744  ubi_err("no free eraseblocks");
745  return ERR_PTR(-ENOSPC);
746 }
747 
765 static int check_corruption(struct ubi_device *ubi, struct ubi_vid_hdr *vid_hdr,
766  int pnum)
767 {
768  int err;
769 
770  mutex_lock(&ubi->buf_mutex);
771  memset(ubi->peb_buf, 0x00, ubi->leb_size);
772 
773  err = ubi_io_read(ubi, ubi->peb_buf, pnum, ubi->leb_start,
774  ubi->leb_size);
775  if (err == UBI_IO_BITFLIPS || mtd_is_eccerr(err)) {
776  /*
777  * Bit-flips or integrity errors while reading the data area.
778  * It is difficult to say for sure what type of corruption is
779  * this, but presumably a power cut happened while this PEB was
780  * erased, so it became unstable and corrupted, and should be
781  * erased.
782  */
783  err = 0;
784  goto out_unlock;
785  }
786 
787  if (err)
788  goto out_unlock;
789 
790  if (ubi_check_pattern(ubi->peb_buf, 0xFF, ubi->leb_size))
791  goto out_unlock;
792 
793  ubi_err("PEB %d contains corrupted VID header, and the data does not contain all 0xFF",
794  pnum);
795  ubi_err("this may be a non-UBI PEB or a severe VID header corruption which requires manual inspection");
796  ubi_dump_vid_hdr(vid_hdr);
797  pr_err("hexdump of PEB %d offset %d, length %d",
798  pnum, ubi->leb_start, ubi->leb_size);
800  ubi->peb_buf, ubi->leb_size, 1);
801  err = 1;
802 
803 out_unlock:
804  mutex_unlock(&ubi->buf_mutex);
805  return err;
806 }
807 
821 static int scan_peb(struct ubi_device *ubi, struct ubi_attach_info *ai,
822  int pnum, int *vid, unsigned long long *sqnum)
823 {
824  long long uninitialized_var(ec);
825  int err, bitflips = 0, vol_id = -1, ec_err = 0;
826 
827  dbg_bld("scan PEB %d", pnum);
828 
829  /* Skip bad physical eraseblocks */
830  err = ubi_io_is_bad(ubi, pnum);
831  if (err < 0)
832  return err;
833  else if (err) {
834  ai->bad_peb_count += 1;
835  return 0;
836  }
837 
838  err = ubi_io_read_ec_hdr(ubi, pnum, ech, 0);
839  if (err < 0)
840  return err;
841  switch (err) {
842  case 0:
843  break;
844  case UBI_IO_BITFLIPS:
845  bitflips = 1;
846  break;
847  case UBI_IO_FF:
848  ai->empty_peb_count += 1;
849  return add_to_list(ai, pnum, UBI_UNKNOWN, UBI_UNKNOWN,
850  UBI_UNKNOWN, 0, &ai->erase);
851  case UBI_IO_FF_BITFLIPS:
852  ai->empty_peb_count += 1;
853  return add_to_list(ai, pnum, UBI_UNKNOWN, UBI_UNKNOWN,
854  UBI_UNKNOWN, 1, &ai->erase);
856  case UBI_IO_BAD_HDR:
857  /*
858  * We have to also look at the VID header, possibly it is not
859  * corrupted. Set %bitflips flag in order to make this PEB be
860  * moved and EC be re-created.
861  */
862  ec_err = err;
863  ec = UBI_UNKNOWN;
864  bitflips = 1;
865  break;
866  default:
867  ubi_err("'ubi_io_read_ec_hdr()' returned unknown code %d", err);
868  return -EINVAL;
869  }
870 
871  if (!ec_err) {
872  int image_seq;
873 
874  /* Make sure UBI version is OK */
875  if (ech->version != UBI_VERSION) {
876  ubi_err("this UBI version is %d, image version is %d",
877  UBI_VERSION, (int)ech->version);
878  return -EINVAL;
879  }
880 
881  ec = be64_to_cpu(ech->ec);
882  if (ec > UBI_MAX_ERASECOUNTER) {
883  /*
884  * Erase counter overflow. The EC headers have 64 bits
885  * reserved, but we anyway make use of only 31 bit
886  * values, as this seems to be enough for any existing
887  * flash. Upgrade UBI and use 64-bit erase counters
888  * internally.
889  */
890  ubi_err("erase counter overflow, max is %d",
892  ubi_dump_ec_hdr(ech);
893  return -EINVAL;
894  }
895 
896  /*
897  * Make sure that all PEBs have the same image sequence number.
898  * This allows us to detect situations when users flash UBI
899  * images incorrectly, so that the flash has the new UBI image
900  * and leftovers from the old one. This feature was added
901  * relatively recently, and the sequence number was always
902  * zero, because old UBI implementations always set it to zero.
903  * For this reasons, we do not panic if some PEBs have zero
904  * sequence number, while other PEBs have non-zero sequence
905  * number.
906  */
907  image_seq = be32_to_cpu(ech->image_seq);
908  if (!ubi->image_seq && image_seq)
909  ubi->image_seq = image_seq;
910  if (ubi->image_seq && image_seq &&
911  ubi->image_seq != image_seq) {
912  ubi_err("bad image sequence number %d in PEB %d, expected %d",
913  image_seq, pnum, ubi->image_seq);
914  ubi_dump_ec_hdr(ech);
915  return -EINVAL;
916  }
917  }
918 
919  /* OK, we've done with the EC header, let's look at the VID header */
920 
921  err = ubi_io_read_vid_hdr(ubi, pnum, vidh, 0);
922  if (err < 0)
923  return err;
924  switch (err) {
925  case 0:
926  break;
927  case UBI_IO_BITFLIPS:
928  bitflips = 1;
929  break;
931  if (ec_err == UBI_IO_BAD_HDR_EBADMSG)
932  /*
933  * Both EC and VID headers are corrupted and were read
934  * with data integrity error, probably this is a bad
935  * PEB, bit it is not marked as bad yet. This may also
936  * be a result of power cut during erasure.
937  */
938  ai->maybe_bad_peb_count += 1;
939  case UBI_IO_BAD_HDR:
940  if (ec_err)
941  /*
942  * Both headers are corrupted. There is a possibility
943  * that this a valid UBI PEB which has corresponding
944  * LEB, but the headers are corrupted. However, it is
945  * impossible to distinguish it from a PEB which just
946  * contains garbage because of a power cut during erase
947  * operation. So we just schedule this PEB for erasure.
948  *
949  * Besides, in case of NOR flash, we deliberately
950  * corrupt both headers because NOR flash erasure is
951  * slow and can start from the end.
952  */
953  err = 0;
954  else
955  /*
956  * The EC was OK, but the VID header is corrupted. We
957  * have to check what is in the data area.
958  */
959  err = check_corruption(ubi, vidh, pnum);
960 
961  if (err < 0)
962  return err;
963  else if (!err)
964  /* This corruption is caused by a power cut */
965  err = add_to_list(ai, pnum, UBI_UNKNOWN,
966  UBI_UNKNOWN, ec, 1, &ai->erase);
967  else
968  /* This is an unexpected corruption */
969  err = add_corrupted(ai, pnum, ec);
970  if (err)
971  return err;
972  goto adjust_mean_ec;
973  case UBI_IO_FF_BITFLIPS:
974  err = add_to_list(ai, pnum, UBI_UNKNOWN, UBI_UNKNOWN,
975  ec, 1, &ai->erase);
976  if (err)
977  return err;
978  goto adjust_mean_ec;
979  case UBI_IO_FF:
980  if (ec_err || bitflips)
981  err = add_to_list(ai, pnum, UBI_UNKNOWN,
982  UBI_UNKNOWN, ec, 1, &ai->erase);
983  else
984  err = add_to_list(ai, pnum, UBI_UNKNOWN,
985  UBI_UNKNOWN, ec, 0, &ai->free);
986  if (err)
987  return err;
988  goto adjust_mean_ec;
989  default:
990  ubi_err("'ubi_io_read_vid_hdr()' returned unknown code %d",
991  err);
992  return -EINVAL;
993  }
994 
995  vol_id = be32_to_cpu(vidh->vol_id);
996  if (vid)
997  *vid = vol_id;
998  if (sqnum)
999  *sqnum = be64_to_cpu(vidh->sqnum);
1000  if (vol_id > UBI_MAX_VOLUMES && vol_id != UBI_LAYOUT_VOLUME_ID) {
1001  int lnum = be32_to_cpu(vidh->lnum);
1002 
1003  /* Unsupported internal volume */
1004  switch (vidh->compat) {
1005  case UBI_COMPAT_DELETE:
1006  if (vol_id != UBI_FM_SB_VOLUME_ID
1007  && vol_id != UBI_FM_DATA_VOLUME_ID) {
1008  ubi_msg("\"delete\" compatible internal volume %d:%d found, will remove it",
1009  vol_id, lnum);
1010  }
1011  err = add_to_list(ai, pnum, vol_id, lnum,
1012  ec, 1, &ai->erase);
1013  if (err)
1014  return err;
1015  return 0;
1016 
1017  case UBI_COMPAT_RO:
1018  ubi_msg("read-only compatible internal volume %d:%d found, switch to read-only mode",
1019  vol_id, lnum);
1020  ubi->ro_mode = 1;
1021  break;
1022 
1023  case UBI_COMPAT_PRESERVE:
1024  ubi_msg("\"preserve\" compatible internal volume %d:%d found",
1025  vol_id, lnum);
1026  err = add_to_list(ai, pnum, vol_id, lnum,
1027  ec, 0, &ai->alien);
1028  if (err)
1029  return err;
1030  return 0;
1031 
1032  case UBI_COMPAT_REJECT:
1033  ubi_err("incompatible internal volume %d:%d found",
1034  vol_id, lnum);
1035  return -EINVAL;
1036  }
1037  }
1038 
1039  if (ec_err)
1040  ubi_warn("valid VID header but corrupted EC header at PEB %d",
1041  pnum);
1042  err = ubi_add_to_av(ubi, ai, pnum, ec, vidh, bitflips);
1043  if (err)
1044  return err;
1045 
1046 adjust_mean_ec:
1047  if (!ec_err) {
1048  ai->ec_sum += ec;
1049  ai->ec_count += 1;
1050  if (ec > ai->max_ec)
1051  ai->max_ec = ec;
1052  if (ec < ai->min_ec)
1053  ai->min_ec = ec;
1054  }
1055 
1056  return 0;
1057 }
1058 
1070 static int late_analysis(struct ubi_device *ubi, struct ubi_attach_info *ai)
1071 {
1072  struct ubi_ainf_peb *aeb;
1073  int max_corr, peb_count;
1074 
1075  peb_count = ubi->peb_count - ai->bad_peb_count - ai->alien_peb_count;
1076  max_corr = peb_count / 20 ?: 8;
1077 
1078  /*
1079  * Few corrupted PEBs is not a problem and may be just a result of
1080  * unclean reboots. However, many of them may indicate some problems
1081  * with the flash HW or driver.
1082  */
1083  if (ai->corr_peb_count) {
1084  ubi_err("%d PEBs are corrupted and preserved",
1085  ai->corr_peb_count);
1086  pr_err("Corrupted PEBs are:");
1087  list_for_each_entry(aeb, &ai->corr, u.list)
1088  pr_cont(" %d", aeb->pnum);
1089  pr_cont("\n");
1090 
1091  /*
1092  * If too many PEBs are corrupted, we refuse attaching,
1093  * otherwise, only print a warning.
1094  */
1095  if (ai->corr_peb_count >= max_corr) {
1096  ubi_err("too many corrupted PEBs, refusing");
1097  return -EINVAL;
1098  }
1099  }
1100 
1101  if (ai->empty_peb_count + ai->maybe_bad_peb_count == peb_count) {
1102  /*
1103  * All PEBs are empty, or almost all - a couple PEBs look like
1104  * they may be bad PEBs which were not marked as bad yet.
1105  *
1106  * This piece of code basically tries to distinguish between
1107  * the following situations:
1108  *
1109  * 1. Flash is empty, but there are few bad PEBs, which are not
1110  * marked as bad so far, and which were read with error. We
1111  * want to go ahead and format this flash. While formatting,
1112  * the faulty PEBs will probably be marked as bad.
1113  *
1114  * 2. Flash contains non-UBI data and we do not want to format
1115  * it and destroy possibly important information.
1116  */
1117  if (ai->maybe_bad_peb_count <= 2) {
1118  ai->is_empty = 1;
1119  ubi_msg("empty MTD device detected");
1121  sizeof(ubi->image_seq));
1122  } else {
1123  ubi_err("MTD device is not UBI-formatted and possibly contains non-UBI data - refusing it");
1124  return -EINVAL;
1125  }
1126 
1127  }
1128 
1129  return 0;
1130 }
1131 
1139 static void destroy_av(struct ubi_attach_info *ai, struct ubi_ainf_volume *av)
1140 {
1141  struct ubi_ainf_peb *aeb;
1142  struct rb_node *this = av->root.rb_node;
1143 
1144  while (this) {
1145  if (this->rb_left)
1146  this = this->rb_left;
1147  else if (this->rb_right)
1148  this = this->rb_right;
1149  else {
1150  aeb = rb_entry(this, struct ubi_ainf_peb, u.rb);
1151  this = rb_parent(this);
1152  if (this) {
1153  if (this->rb_left == &aeb->u.rb)
1154  this->rb_left = NULL;
1155  else
1156  this->rb_right = NULL;
1157  }
1158 
1159  kmem_cache_free(ai->aeb_slab_cache, aeb);
1160  }
1161  }
1162  kfree(av);
1163 }
1164 
1169 static void destroy_ai(struct ubi_attach_info *ai)
1170 {
1171  struct ubi_ainf_peb *aeb, *aeb_tmp;
1172  struct ubi_ainf_volume *av;
1173  struct rb_node *rb;
1174 
1175  list_for_each_entry_safe(aeb, aeb_tmp, &ai->alien, u.list) {
1176  list_del(&aeb->u.list);
1177  kmem_cache_free(ai->aeb_slab_cache, aeb);
1178  }
1179  list_for_each_entry_safe(aeb, aeb_tmp, &ai->erase, u.list) {
1180  list_del(&aeb->u.list);
1181  kmem_cache_free(ai->aeb_slab_cache, aeb);
1182  }
1183  list_for_each_entry_safe(aeb, aeb_tmp, &ai->corr, u.list) {
1184  list_del(&aeb->u.list);
1185  kmem_cache_free(ai->aeb_slab_cache, aeb);
1186  }
1187  list_for_each_entry_safe(aeb, aeb_tmp, &ai->free, u.list) {
1188  list_del(&aeb->u.list);
1189  kmem_cache_free(ai->aeb_slab_cache, aeb);
1190  }
1191 
1192  /* Destroy the volume RB-tree */
1193  rb = ai->volumes.rb_node;
1194  while (rb) {
1195  if (rb->rb_left)
1196  rb = rb->rb_left;
1197  else if (rb->rb_right)
1198  rb = rb->rb_right;
1199  else {
1200  av = rb_entry(rb, struct ubi_ainf_volume, rb);
1201 
1202  rb = rb_parent(rb);
1203  if (rb) {
1204  if (rb->rb_left == &av->rb)
1205  rb->rb_left = NULL;
1206  else
1207  rb->rb_right = NULL;
1208  }
1209 
1210  destroy_av(ai, av);
1211  }
1212  }
1213 
1214  if (ai->aeb_slab_cache)
1216 
1217  kfree(ai);
1218 }
1219 
1230 static int scan_all(struct ubi_device *ubi, struct ubi_attach_info *ai,
1231  int start)
1232 {
1233  int err, pnum;
1234  struct rb_node *rb1, *rb2;
1235  struct ubi_ainf_volume *av;
1236  struct ubi_ainf_peb *aeb;
1237 
1238  err = -ENOMEM;
1239 
1240  ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
1241  if (!ech)
1242  return err;
1243 
1244  vidh = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL);
1245  if (!vidh)
1246  goto out_ech;
1247 
1248  for (pnum = start; pnum < ubi->peb_count; pnum++) {
1249  cond_resched();
1250 
1251  dbg_gen("process PEB %d", pnum);
1252  err = scan_peb(ubi, ai, pnum, NULL, NULL);
1253  if (err < 0)
1254  goto out_vidh;
1255  }
1256 
1257  ubi_msg("scanning is finished");
1258 
1259  /* Calculate mean erase counter */
1260  if (ai->ec_count)
1261  ai->mean_ec = div_u64(ai->ec_sum, ai->ec_count);
1262 
1263  err = late_analysis(ubi, ai);
1264  if (err)
1265  goto out_vidh;
1266 
1267  /*
1268  * In case of unknown erase counter we use the mean erase counter
1269  * value.
1270  */
1271  ubi_rb_for_each_entry(rb1, av, &ai->volumes, rb) {
1272  ubi_rb_for_each_entry(rb2, aeb, &av->root, u.rb)
1273  if (aeb->ec == UBI_UNKNOWN)
1274  aeb->ec = ai->mean_ec;
1275  }
1276 
1277  list_for_each_entry(aeb, &ai->free, u.list) {
1278  if (aeb->ec == UBI_UNKNOWN)
1279  aeb->ec = ai->mean_ec;
1280  }
1281 
1282  list_for_each_entry(aeb, &ai->corr, u.list)
1283  if (aeb->ec == UBI_UNKNOWN)
1284  aeb->ec = ai->mean_ec;
1285 
1286  list_for_each_entry(aeb, &ai->erase, u.list)
1287  if (aeb->ec == UBI_UNKNOWN)
1288  aeb->ec = ai->mean_ec;
1289 
1290  err = self_check_ai(ubi, ai);
1291  if (err)
1292  goto out_vidh;
1293 
1294  ubi_free_vid_hdr(ubi, vidh);
1295  kfree(ech);
1296 
1297  return 0;
1298 
1299 out_vidh:
1300  ubi_free_vid_hdr(ubi, vidh);
1301 out_ech:
1302  kfree(ech);
1303  return err;
1304 }
1305 
1306 #ifdef CONFIG_MTD_UBI_FASTMAP
1307 
1318 static int scan_fast(struct ubi_device *ubi, struct ubi_attach_info *ai)
1319 {
1320  int err, pnum, fm_anchor = -1;
1321  unsigned long long max_sqnum = 0;
1322 
1323  err = -ENOMEM;
1324 
1325  ech = kzalloc(ubi->ec_hdr_alsize, GFP_KERNEL);
1326  if (!ech)
1327  goto out;
1328 
1329  vidh = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL);
1330  if (!vidh)
1331  goto out_ech;
1332 
1333  for (pnum = 0; pnum < UBI_FM_MAX_START; pnum++) {
1334  int vol_id = -1;
1335  unsigned long long sqnum = -1;
1336  cond_resched();
1337 
1338  dbg_gen("process PEB %d", pnum);
1339  err = scan_peb(ubi, ai, pnum, &vol_id, &sqnum);
1340  if (err < 0)
1341  goto out_vidh;
1342 
1343  if (vol_id == UBI_FM_SB_VOLUME_ID && sqnum > max_sqnum) {
1344  max_sqnum = sqnum;
1345  fm_anchor = pnum;
1346  }
1347  }
1348 
1349  ubi_free_vid_hdr(ubi, vidh);
1350  kfree(ech);
1351 
1352  if (fm_anchor < 0)
1353  return UBI_NO_FASTMAP;
1354 
1355  return ubi_scan_fastmap(ubi, ai, fm_anchor);
1356 
1357 out_vidh:
1358  ubi_free_vid_hdr(ubi, vidh);
1359 out_ech:
1360  kfree(ech);
1361 out:
1362  return err;
1363 }
1364 
1365 #endif
1366 
1367 static struct ubi_attach_info *alloc_ai(const char *slab_name)
1368 {
1369  struct ubi_attach_info *ai;
1370 
1371  ai = kzalloc(sizeof(struct ubi_attach_info), GFP_KERNEL);
1372  if (!ai)
1373  return ai;
1374 
1375  INIT_LIST_HEAD(&ai->corr);
1376  INIT_LIST_HEAD(&ai->free);
1377  INIT_LIST_HEAD(&ai->erase);
1378  INIT_LIST_HEAD(&ai->alien);
1379  ai->volumes = RB_ROOT;
1380  ai->aeb_slab_cache = kmem_cache_create(slab_name,
1381  sizeof(struct ubi_ainf_peb),
1382  0, 0, NULL);
1383  if (!ai->aeb_slab_cache) {
1384  kfree(ai);
1385  ai = NULL;
1386  }
1387 
1388  return ai;
1389 }
1390 
1399 int ubi_attach(struct ubi_device *ubi, int force_scan)
1400 {
1401  int err;
1402  struct ubi_attach_info *ai;
1403 
1404  ai = alloc_ai("ubi_aeb_slab_cache");
1405  if (!ai)
1406  return -ENOMEM;
1407 
1408 #ifdef CONFIG_MTD_UBI_FASTMAP
1409  /* On small flash devices we disable fastmap in any case. */
1410  if ((int)mtd_div_by_eb(ubi->mtd->size, ubi->mtd) <= UBI_FM_MAX_START) {
1411  ubi->fm_disabled = 1;
1412  force_scan = 1;
1413  }
1414 
1415  if (force_scan)
1416  err = scan_all(ubi, ai, 0);
1417  else {
1418  err = scan_fast(ubi, ai);
1419  if (err > 0) {
1420  if (err != UBI_NO_FASTMAP) {
1421  destroy_ai(ai);
1422  ai = alloc_ai("ubi_aeb_slab_cache2");
1423  if (!ai)
1424  return -ENOMEM;
1425  }
1426 
1427  err = scan_all(ubi, ai, UBI_FM_MAX_START);
1428  }
1429  }
1430 #else
1431  err = scan_all(ubi, ai, 0);
1432 #endif
1433  if (err)
1434  goto out_ai;
1435 
1436  ubi->bad_peb_count = ai->bad_peb_count;
1437  ubi->good_peb_count = ubi->peb_count - ubi->bad_peb_count;
1438  ubi->corr_peb_count = ai->corr_peb_count;
1439  ubi->max_ec = ai->max_ec;
1440  ubi->mean_ec = ai->mean_ec;
1441  dbg_gen("max. sequence number: %llu", ai->max_sqnum);
1442 
1443  err = ubi_read_volume_table(ubi, ai);
1444  if (err)
1445  goto out_ai;
1446 
1447  err = ubi_wl_init(ubi, ai);
1448  if (err)
1449  goto out_vtbl;
1450 
1451  err = ubi_eba_init(ubi, ai);
1452  if (err)
1453  goto out_wl;
1454 
1455 #ifdef CONFIG_MTD_UBI_FASTMAP
1456  if (ubi->fm && ubi->dbg->chk_gen) {
1457  struct ubi_attach_info *scan_ai;
1458 
1459  scan_ai = alloc_ai("ubi_ckh_aeb_slab_cache");
1460  if (!scan_ai)
1461  goto out_wl;
1462 
1463  err = scan_all(ubi, scan_ai, 0);
1464  if (err) {
1465  destroy_ai(scan_ai);
1466  goto out_wl;
1467  }
1468 
1469  err = self_check_eba(ubi, ai, scan_ai);
1470  destroy_ai(scan_ai);
1471 
1472  if (err)
1473  goto out_wl;
1474  }
1475 #endif
1476 
1477  destroy_ai(ai);
1478  return 0;
1479 
1480 out_wl:
1481  ubi_wl_close(ubi);
1482 out_vtbl:
1484  vfree(ubi->vtbl);
1485 out_ai:
1486  destroy_ai(ai);
1487  return err;
1488 }
1489 
1498 static int self_check_ai(struct ubi_device *ubi, struct ubi_attach_info *ai)
1499 {
1500  int pnum, err, vols_found = 0;
1501  struct rb_node *rb1, *rb2;
1502  struct ubi_ainf_volume *av;
1503  struct ubi_ainf_peb *aeb, *last_aeb;
1504  uint8_t *buf;
1505 
1506  if (!ubi->dbg->chk_gen)
1507  return 0;
1508 
1509  /*
1510  * At first, check that attaching information is OK.
1511  */
1512  ubi_rb_for_each_entry(rb1, av, &ai->volumes, rb) {
1513  int leb_count = 0;
1514 
1515  cond_resched();
1516 
1517  vols_found += 1;
1518 
1519  if (ai->is_empty) {
1520  ubi_err("bad is_empty flag");
1521  goto bad_av;
1522  }
1523 
1524  if (av->vol_id < 0 || av->highest_lnum < 0 ||
1525  av->leb_count < 0 || av->vol_type < 0 || av->used_ebs < 0 ||
1526  av->data_pad < 0 || av->last_data_size < 0) {
1527  ubi_err("negative values");
1528  goto bad_av;
1529  }
1530 
1531  if (av->vol_id >= UBI_MAX_VOLUMES &&
1533  ubi_err("bad vol_id");
1534  goto bad_av;
1535  }
1536 
1537  if (av->vol_id > ai->highest_vol_id) {
1538  ubi_err("highest_vol_id is %d, but vol_id %d is there",
1539  ai->highest_vol_id, av->vol_id);
1540  goto out;
1541  }
1542 
1543  if (av->vol_type != UBI_DYNAMIC_VOLUME &&
1544  av->vol_type != UBI_STATIC_VOLUME) {
1545  ubi_err("bad vol_type");
1546  goto bad_av;
1547  }
1548 
1549  if (av->data_pad > ubi->leb_size / 2) {
1550  ubi_err("bad data_pad");
1551  goto bad_av;
1552  }
1553 
1554  last_aeb = NULL;
1555  ubi_rb_for_each_entry(rb2, aeb, &av->root, u.rb) {
1556  cond_resched();
1557 
1558  last_aeb = aeb;
1559  leb_count += 1;
1560 
1561  if (aeb->pnum < 0 || aeb->ec < 0) {
1562  ubi_err("negative values");
1563  goto bad_aeb;
1564  }
1565 
1566  if (aeb->ec < ai->min_ec) {
1567  ubi_err("bad ai->min_ec (%d), %d found",
1568  ai->min_ec, aeb->ec);
1569  goto bad_aeb;
1570  }
1571 
1572  if (aeb->ec > ai->max_ec) {
1573  ubi_err("bad ai->max_ec (%d), %d found",
1574  ai->max_ec, aeb->ec);
1575  goto bad_aeb;
1576  }
1577 
1578  if (aeb->pnum >= ubi->peb_count) {
1579  ubi_err("too high PEB number %d, total PEBs %d",
1580  aeb->pnum, ubi->peb_count);
1581  goto bad_aeb;
1582  }
1583 
1584  if (av->vol_type == UBI_STATIC_VOLUME) {
1585  if (aeb->lnum >= av->used_ebs) {
1586  ubi_err("bad lnum or used_ebs");
1587  goto bad_aeb;
1588  }
1589  } else {
1590  if (av->used_ebs != 0) {
1591  ubi_err("non-zero used_ebs");
1592  goto bad_aeb;
1593  }
1594  }
1595 
1596  if (aeb->lnum > av->highest_lnum) {
1597  ubi_err("incorrect highest_lnum or lnum");
1598  goto bad_aeb;
1599  }
1600  }
1601 
1602  if (av->leb_count != leb_count) {
1603  ubi_err("bad leb_count, %d objects in the tree",
1604  leb_count);
1605  goto bad_av;
1606  }
1607 
1608  if (!last_aeb)
1609  continue;
1610 
1611  aeb = last_aeb;
1612 
1613  if (aeb->lnum != av->highest_lnum) {
1614  ubi_err("bad highest_lnum");
1615  goto bad_aeb;
1616  }
1617  }
1618 
1619  if (vols_found != ai->vols_found) {
1620  ubi_err("bad ai->vols_found %d, should be %d",
1621  ai->vols_found, vols_found);
1622  goto out;
1623  }
1624 
1625  /* Check that attaching information is correct */
1626  ubi_rb_for_each_entry(rb1, av, &ai->volumes, rb) {
1627  last_aeb = NULL;
1628  ubi_rb_for_each_entry(rb2, aeb, &av->root, u.rb) {
1629  int vol_type;
1630 
1631  cond_resched();
1632 
1633  last_aeb = aeb;
1634 
1635  err = ubi_io_read_vid_hdr(ubi, aeb->pnum, vidh, 1);
1636  if (err && err != UBI_IO_BITFLIPS) {
1637  ubi_err("VID header is not OK (%d)", err);
1638  if (err > 0)
1639  err = -EIO;
1640  return err;
1641  }
1642 
1643  vol_type = vidh->vol_type == UBI_VID_DYNAMIC ?
1645  if (av->vol_type != vol_type) {
1646  ubi_err("bad vol_type");
1647  goto bad_vid_hdr;
1648  }
1649 
1650  if (aeb->sqnum != be64_to_cpu(vidh->sqnum)) {
1651  ubi_err("bad sqnum %llu", aeb->sqnum);
1652  goto bad_vid_hdr;
1653  }
1654 
1655  if (av->vol_id != be32_to_cpu(vidh->vol_id)) {
1656  ubi_err("bad vol_id %d", av->vol_id);
1657  goto bad_vid_hdr;
1658  }
1659 
1660  if (av->compat != vidh->compat) {
1661  ubi_err("bad compat %d", vidh->compat);
1662  goto bad_vid_hdr;
1663  }
1664 
1665  if (aeb->lnum != be32_to_cpu(vidh->lnum)) {
1666  ubi_err("bad lnum %d", aeb->lnum);
1667  goto bad_vid_hdr;
1668  }
1669 
1670  if (av->used_ebs != be32_to_cpu(vidh->used_ebs)) {
1671  ubi_err("bad used_ebs %d", av->used_ebs);
1672  goto bad_vid_hdr;
1673  }
1674 
1675  if (av->data_pad != be32_to_cpu(vidh->data_pad)) {
1676  ubi_err("bad data_pad %d", av->data_pad);
1677  goto bad_vid_hdr;
1678  }
1679  }
1680 
1681  if (!last_aeb)
1682  continue;
1683 
1684  if (av->highest_lnum != be32_to_cpu(vidh->lnum)) {
1685  ubi_err("bad highest_lnum %d", av->highest_lnum);
1686  goto bad_vid_hdr;
1687  }
1688 
1689  if (av->last_data_size != be32_to_cpu(vidh->data_size)) {
1690  ubi_err("bad last_data_size %d", av->last_data_size);
1691  goto bad_vid_hdr;
1692  }
1693  }
1694 
1695  /*
1696  * Make sure that all the physical eraseblocks are in one of the lists
1697  * or trees.
1698  */
1699  buf = kzalloc(ubi->peb_count, GFP_KERNEL);
1700  if (!buf)
1701  return -ENOMEM;
1702 
1703  for (pnum = 0; pnum < ubi->peb_count; pnum++) {
1704  err = ubi_io_is_bad(ubi, pnum);
1705  if (err < 0) {
1706  kfree(buf);
1707  return err;
1708  } else if (err)
1709  buf[pnum] = 1;
1710  }
1711 
1712  ubi_rb_for_each_entry(rb1, av, &ai->volumes, rb)
1713  ubi_rb_for_each_entry(rb2, aeb, &av->root, u.rb)
1714  buf[aeb->pnum] = 1;
1715 
1716  list_for_each_entry(aeb, &ai->free, u.list)
1717  buf[aeb->pnum] = 1;
1718 
1719  list_for_each_entry(aeb, &ai->corr, u.list)
1720  buf[aeb->pnum] = 1;
1721 
1722  list_for_each_entry(aeb, &ai->erase, u.list)
1723  buf[aeb->pnum] = 1;
1724 
1725  list_for_each_entry(aeb, &ai->alien, u.list)
1726  buf[aeb->pnum] = 1;
1727 
1728  err = 0;
1729  for (pnum = 0; pnum < ubi->peb_count; pnum++)
1730  if (!buf[pnum]) {
1731  ubi_err("PEB %d is not referred", pnum);
1732  err = 1;
1733  }
1734 
1735  kfree(buf);
1736  if (err)
1737  goto out;
1738  return 0;
1739 
1740 bad_aeb:
1741  ubi_err("bad attaching information about LEB %d", aeb->lnum);
1742  ubi_dump_aeb(aeb, 0);
1743  ubi_dump_av(av);
1744  goto out;
1745 
1746 bad_av:
1747  ubi_err("bad attaching information about volume %d", av->vol_id);
1748  ubi_dump_av(av);
1749  goto out;
1750 
1751 bad_vid_hdr:
1752  ubi_err("bad attaching information about volume %d", av->vol_id);
1753  ubi_dump_av(av);
1754  ubi_dump_vid_hdr(vidh);
1755 
1756 out:
1757  dump_stack();
1758  return -EINVAL;
1759 }