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build.c
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1 /*
2  * Copyright (c) International Business Machines Corp., 2006
3  * Copyright (c) Nokia Corporation, 2007
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
13  * the GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18  *
19  * Author: Artem Bityutskiy (Битюцкий Артём),
20  * Frank Haverkamp
21  */
22 
23 /*
24  * This file includes UBI initialization and building of UBI devices.
25  *
26  * When UBI is initialized, it attaches all the MTD devices specified as the
27  * module load parameters or the kernel boot parameters. If MTD devices were
28  * specified, UBI does not attach any MTD device, but it is possible to do
29  * later using the "UBI control device".
30  */
31 
32 #include <linux/err.h>
33 #include <linux/module.h>
34 #include <linux/moduleparam.h>
35 #include <linux/stringify.h>
36 #include <linux/namei.h>
37 #include <linux/stat.h>
38 #include <linux/miscdevice.h>
39 #include <linux/mtd/partitions.h>
40 #include <linux/log2.h>
41 #include <linux/kthread.h>
42 #include <linux/kernel.h>
43 #include <linux/slab.h>
44 #include "ubi.h"
45 
46 /* Maximum length of the 'mtd=' parameter */
47 #define MTD_PARAM_LEN_MAX 64
48 
49 /* Maximum number of comma-separated items in the 'mtd=' parameter */
50 #define MTD_PARAM_MAX_COUNT 3
51 
52 /* Maximum value for the number of bad PEBs per 1024 PEBs */
53 #define MAX_MTD_UBI_BEB_LIMIT 768
54 
55 #ifdef CONFIG_MTD_UBI_MODULE
56 #define ubi_is_module() 1
57 #else
58 #define ubi_is_module() 0
59 #endif
60 
68 struct mtd_dev_param {
72 };
73 
74 /* Numbers of elements set in the @mtd_dev_param array */
75 static int __initdata mtd_devs;
76 
77 /* MTD devices specification parameters */
79 #ifdef CONFIG_MTD_UBI_FASTMAP
80 /* UBI module parameter to enable fastmap automatically on non-fastmap images */
81 static bool fm_autoconvert;
82 #endif
83 /* Root UBI "class" object (corresponds to '/<sysfs>/class/ubi/') */
84 struct class *ubi_class;
85 
86 /* Slab cache for wear-leveling entries */
88 
89 /* UBI control character device */
90 static struct miscdevice ubi_ctrl_cdev = {
91  .minor = MISC_DYNAMIC_MINOR,
92  .name = "ubi_ctrl",
93  .fops = &ubi_ctrl_cdev_operations,
94 };
95 
96 /* All UBI devices in system */
97 static struct ubi_device *ubi_devices[UBI_MAX_DEVICES];
98 
99 /* Serializes UBI devices creations and removals */
100 DEFINE_MUTEX(ubi_devices_mutex);
101 
102 /* Protects @ubi_devices and @ubi->ref_count */
103 static DEFINE_SPINLOCK(ubi_devices_lock);
104 
105 /* "Show" method for files in '/<sysfs>/class/ubi/' */
106 static ssize_t ubi_version_show(struct class *class,
107  struct class_attribute *attr, char *buf)
108 {
109  return sprintf(buf, "%d\n", UBI_VERSION);
110 }
111 
112 /* UBI version attribute ('/<sysfs>/class/ubi/version') */
113 static struct class_attribute ubi_version =
114  __ATTR(version, S_IRUGO, ubi_version_show, NULL);
115 
116 static ssize_t dev_attribute_show(struct device *dev,
117  struct device_attribute *attr, char *buf);
118 
119 /* UBI device attributes (correspond to files in '/<sysfs>/class/ubi/ubiX') */
120 static struct device_attribute dev_eraseblock_size =
121  __ATTR(eraseblock_size, S_IRUGO, dev_attribute_show, NULL);
122 static struct device_attribute dev_avail_eraseblocks =
123  __ATTR(avail_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
124 static struct device_attribute dev_total_eraseblocks =
125  __ATTR(total_eraseblocks, S_IRUGO, dev_attribute_show, NULL);
126 static struct device_attribute dev_volumes_count =
127  __ATTR(volumes_count, S_IRUGO, dev_attribute_show, NULL);
128 static struct device_attribute dev_max_ec =
129  __ATTR(max_ec, S_IRUGO, dev_attribute_show, NULL);
130 static struct device_attribute dev_reserved_for_bad =
131  __ATTR(reserved_for_bad, S_IRUGO, dev_attribute_show, NULL);
132 static struct device_attribute dev_bad_peb_count =
133  __ATTR(bad_peb_count, S_IRUGO, dev_attribute_show, NULL);
134 static struct device_attribute dev_max_vol_count =
135  __ATTR(max_vol_count, S_IRUGO, dev_attribute_show, NULL);
136 static struct device_attribute dev_min_io_size =
137  __ATTR(min_io_size, S_IRUGO, dev_attribute_show, NULL);
138 static struct device_attribute dev_bgt_enabled =
139  __ATTR(bgt_enabled, S_IRUGO, dev_attribute_show, NULL);
140 static struct device_attribute dev_mtd_num =
141  __ATTR(mtd_num, S_IRUGO, dev_attribute_show, NULL);
142 
153 int ubi_volume_notify(struct ubi_device *ubi, struct ubi_volume *vol, int ntype)
154 {
155  struct ubi_notification nt;
156 
157  ubi_do_get_device_info(ubi, &nt.di);
158  ubi_do_get_volume_info(ubi, vol, &nt.vi);
159 
160 #ifdef CONFIG_MTD_UBI_FASTMAP
161  switch (ntype) {
162  case UBI_VOLUME_ADDED:
163  case UBI_VOLUME_REMOVED:
164  case UBI_VOLUME_RESIZED:
165  case UBI_VOLUME_RENAMED:
166  if (ubi_update_fastmap(ubi)) {
167  ubi_err("Unable to update fastmap!");
168  ubi_ro_mode(ubi);
169  }
170  }
171 #endif
172  return blocking_notifier_call_chain(&ubi_notifiers, ntype, &nt);
173 }
174 
186 int ubi_notify_all(struct ubi_device *ubi, int ntype, struct notifier_block *nb)
187 {
188  struct ubi_notification nt;
189  int i, count = 0;
190 
191  ubi_do_get_device_info(ubi, &nt.di);
192 
193  mutex_lock(&ubi->device_mutex);
194  for (i = 0; i < ubi->vtbl_slots; i++) {
195  /*
196  * Since the @ubi->device is locked, and we are not going to
197  * change @ubi->volumes, we do not have to lock
198  * @ubi->volumes_lock.
199  */
200  if (!ubi->volumes[i])
201  continue;
202 
203  ubi_do_get_volume_info(ubi, ubi->volumes[i], &nt.vi);
204  if (nb)
205  nb->notifier_call(nb, ntype, &nt);
206  else
208  &nt);
209  count += 1;
210  }
211  mutex_unlock(&ubi->device_mutex);
212 
213  return count;
214 }
215 
226 {
227  int i, count = 0;
228 
229  /*
230  * Since the @ubi_devices_mutex is locked, and we are not going to
231  * change @ubi_devices, we do not have to lock @ubi_devices_lock.
232  */
233  for (i = 0; i < UBI_MAX_DEVICES; i++) {
234  struct ubi_device *ubi = ubi_devices[i];
235 
236  if (!ubi)
237  continue;
238  count += ubi_notify_all(ubi, UBI_VOLUME_ADDED, nb);
239  }
240 
241  return count;
242 }
243 
254 {
255  struct ubi_device *ubi;
256 
257  spin_lock(&ubi_devices_lock);
258  ubi = ubi_devices[ubi_num];
259  if (ubi) {
260  ubi_assert(ubi->ref_count >= 0);
261  ubi->ref_count += 1;
262  get_device(&ubi->dev);
263  }
264  spin_unlock(&ubi_devices_lock);
265 
266  return ubi;
267 }
268 
273 void ubi_put_device(struct ubi_device *ubi)
274 {
275  spin_lock(&ubi_devices_lock);
276  ubi->ref_count -= 1;
277  put_device(&ubi->dev);
278  spin_unlock(&ubi_devices_lock);
279 }
280 
288 struct ubi_device *ubi_get_by_major(int major)
289 {
290  int i;
291  struct ubi_device *ubi;
292 
293  spin_lock(&ubi_devices_lock);
294  for (i = 0; i < UBI_MAX_DEVICES; i++) {
295  ubi = ubi_devices[i];
296  if (ubi && MAJOR(ubi->cdev.dev) == major) {
297  ubi_assert(ubi->ref_count >= 0);
298  ubi->ref_count += 1;
299  get_device(&ubi->dev);
300  spin_unlock(&ubi_devices_lock);
301  return ubi;
302  }
303  }
304  spin_unlock(&ubi_devices_lock);
305 
306  return NULL;
307 }
308 
317 int ubi_major2num(int major)
318 {
319  int i, ubi_num = -ENODEV;
320 
321  spin_lock(&ubi_devices_lock);
322  for (i = 0; i < UBI_MAX_DEVICES; i++) {
323  struct ubi_device *ubi = ubi_devices[i];
324 
325  if (ubi && MAJOR(ubi->cdev.dev) == major) {
326  ubi_num = ubi->ubi_num;
327  break;
328  }
329  }
330  spin_unlock(&ubi_devices_lock);
331 
332  return ubi_num;
333 }
334 
335 /* "Show" method for files in '/<sysfs>/class/ubi/ubiX/' */
336 static ssize_t dev_attribute_show(struct device *dev,
337  struct device_attribute *attr, char *buf)
338 {
339  ssize_t ret;
340  struct ubi_device *ubi;
341 
342  /*
343  * The below code looks weird, but it actually makes sense. We get the
344  * UBI device reference from the contained 'struct ubi_device'. But it
345  * is unclear if the device was removed or not yet. Indeed, if the
346  * device was removed before we increased its reference count,
347  * 'ubi_get_device()' will return -ENODEV and we fail.
348  *
349  * Remember, 'struct ubi_device' is freed in the release function, so
350  * we still can use 'ubi->ubi_num'.
351  */
352  ubi = container_of(dev, struct ubi_device, dev);
353  ubi = ubi_get_device(ubi->ubi_num);
354  if (!ubi)
355  return -ENODEV;
356 
357  if (attr == &dev_eraseblock_size)
358  ret = sprintf(buf, "%d\n", ubi->leb_size);
359  else if (attr == &dev_avail_eraseblocks)
360  ret = sprintf(buf, "%d\n", ubi->avail_pebs);
361  else if (attr == &dev_total_eraseblocks)
362  ret = sprintf(buf, "%d\n", ubi->good_peb_count);
363  else if (attr == &dev_volumes_count)
364  ret = sprintf(buf, "%d\n", ubi->vol_count - UBI_INT_VOL_COUNT);
365  else if (attr == &dev_max_ec)
366  ret = sprintf(buf, "%d\n", ubi->max_ec);
367  else if (attr == &dev_reserved_for_bad)
368  ret = sprintf(buf, "%d\n", ubi->beb_rsvd_pebs);
369  else if (attr == &dev_bad_peb_count)
370  ret = sprintf(buf, "%d\n", ubi->bad_peb_count);
371  else if (attr == &dev_max_vol_count)
372  ret = sprintf(buf, "%d\n", ubi->vtbl_slots);
373  else if (attr == &dev_min_io_size)
374  ret = sprintf(buf, "%d\n", ubi->min_io_size);
375  else if (attr == &dev_bgt_enabled)
376  ret = sprintf(buf, "%d\n", ubi->thread_enabled);
377  else if (attr == &dev_mtd_num)
378  ret = sprintf(buf, "%d\n", ubi->mtd->index);
379  else
380  ret = -EINVAL;
381 
382  ubi_put_device(ubi);
383  return ret;
384 }
385 
386 static void dev_release(struct device *dev)
387 {
388  struct ubi_device *ubi = container_of(dev, struct ubi_device, dev);
389 
390  kfree(ubi);
391 }
392 
402 static int ubi_sysfs_init(struct ubi_device *ubi, int *ref)
403 {
404  int err;
405 
406  ubi->dev.release = dev_release;
407  ubi->dev.devt = ubi->cdev.dev;
408  ubi->dev.class = ubi_class;
409  dev_set_name(&ubi->dev, UBI_NAME_STR"%d", ubi->ubi_num);
410  err = device_register(&ubi->dev);
411  if (err)
412  return err;
413 
414  *ref = 1;
415  err = device_create_file(&ubi->dev, &dev_eraseblock_size);
416  if (err)
417  return err;
418  err = device_create_file(&ubi->dev, &dev_avail_eraseblocks);
419  if (err)
420  return err;
421  err = device_create_file(&ubi->dev, &dev_total_eraseblocks);
422  if (err)
423  return err;
424  err = device_create_file(&ubi->dev, &dev_volumes_count);
425  if (err)
426  return err;
427  err = device_create_file(&ubi->dev, &dev_max_ec);
428  if (err)
429  return err;
430  err = device_create_file(&ubi->dev, &dev_reserved_for_bad);
431  if (err)
432  return err;
433  err = device_create_file(&ubi->dev, &dev_bad_peb_count);
434  if (err)
435  return err;
436  err = device_create_file(&ubi->dev, &dev_max_vol_count);
437  if (err)
438  return err;
439  err = device_create_file(&ubi->dev, &dev_min_io_size);
440  if (err)
441  return err;
442  err = device_create_file(&ubi->dev, &dev_bgt_enabled);
443  if (err)
444  return err;
445  err = device_create_file(&ubi->dev, &dev_mtd_num);
446  return err;
447 }
448 
453 static void ubi_sysfs_close(struct ubi_device *ubi)
454 {
455  device_remove_file(&ubi->dev, &dev_mtd_num);
456  device_remove_file(&ubi->dev, &dev_bgt_enabled);
457  device_remove_file(&ubi->dev, &dev_min_io_size);
458  device_remove_file(&ubi->dev, &dev_max_vol_count);
459  device_remove_file(&ubi->dev, &dev_bad_peb_count);
460  device_remove_file(&ubi->dev, &dev_reserved_for_bad);
461  device_remove_file(&ubi->dev, &dev_max_ec);
462  device_remove_file(&ubi->dev, &dev_volumes_count);
463  device_remove_file(&ubi->dev, &dev_total_eraseblocks);
464  device_remove_file(&ubi->dev, &dev_avail_eraseblocks);
465  device_remove_file(&ubi->dev, &dev_eraseblock_size);
466  device_unregister(&ubi->dev);
467 }
468 
473 static void kill_volumes(struct ubi_device *ubi)
474 {
475  int i;
476 
477  for (i = 0; i < ubi->vtbl_slots; i++)
478  if (ubi->volumes[i])
479  ubi_free_volume(ubi, ubi->volumes[i]);
480 }
481 
500 static int uif_init(struct ubi_device *ubi, int *ref)
501 {
502  int i, err;
503  dev_t dev;
504 
505  *ref = 0;
506  sprintf(ubi->ubi_name, UBI_NAME_STR "%d", ubi->ubi_num);
507 
508  /*
509  * Major numbers for the UBI character devices are allocated
510  * dynamically. Major numbers of volume character devices are
511  * equivalent to ones of the corresponding UBI character device. Minor
512  * numbers of UBI character devices are 0, while minor numbers of
513  * volume character devices start from 1. Thus, we allocate one major
514  * number and ubi->vtbl_slots + 1 minor numbers.
515  */
516  err = alloc_chrdev_region(&dev, 0, ubi->vtbl_slots + 1, ubi->ubi_name);
517  if (err) {
518  ubi_err("cannot register UBI character devices");
519  return err;
520  }
521 
522  ubi_assert(MINOR(dev) == 0);
524  dbg_gen("%s major is %u", ubi->ubi_name, MAJOR(dev));
525  ubi->cdev.owner = THIS_MODULE;
526 
527  err = cdev_add(&ubi->cdev, dev, 1);
528  if (err) {
529  ubi_err("cannot add character device");
530  goto out_unreg;
531  }
532 
533  err = ubi_sysfs_init(ubi, ref);
534  if (err)
535  goto out_sysfs;
536 
537  for (i = 0; i < ubi->vtbl_slots; i++)
538  if (ubi->volumes[i]) {
539  err = ubi_add_volume(ubi, ubi->volumes[i]);
540  if (err) {
541  ubi_err("cannot add volume %d", i);
542  goto out_volumes;
543  }
544  }
545 
546  return 0;
547 
548 out_volumes:
549  kill_volumes(ubi);
550 out_sysfs:
551  if (*ref)
552  get_device(&ubi->dev);
553  ubi_sysfs_close(ubi);
554  cdev_del(&ubi->cdev);
555 out_unreg:
556  unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
557  ubi_err("cannot initialize UBI %s, error %d", ubi->ubi_name, err);
558  return err;
559 }
560 
569 static void uif_close(struct ubi_device *ubi)
570 {
571  kill_volumes(ubi);
572  ubi_sysfs_close(ubi);
573  cdev_del(&ubi->cdev);
574  unregister_chrdev_region(ubi->cdev.dev, ubi->vtbl_slots + 1);
575 }
576 
582 {
583  int i;
584 
585  for (i = ubi->vtbl_slots;
586  i < ubi->vtbl_slots + UBI_INT_VOL_COUNT; i++) {
587  kfree(ubi->volumes[i]->eba_tbl);
588  kfree(ubi->volumes[i]);
589  }
590 }
591 
592 static int get_bad_peb_limit(const struct ubi_device *ubi, int max_beb_per1024)
593 {
594  int limit, device_pebs;
595  uint64_t device_size;
596 
597  if (!max_beb_per1024)
598  return 0;
599 
600  /*
601  * Here we are using size of the entire flash chip and
602  * not just the MTD partition size because the maximum
603  * number of bad eraseblocks is a percentage of the
604  * whole device and bad eraseblocks are not fairly
605  * distributed over the flash chip. So the worst case
606  * is that all the bad eraseblocks of the chip are in
607  * the MTD partition we are attaching (ubi->mtd).
608  */
609  device_size = mtd_get_device_size(ubi->mtd);
610  device_pebs = mtd_div_by_eb(device_size, ubi->mtd);
611  limit = mult_frac(device_pebs, max_beb_per1024, 1024);
612 
613  /* Round it up */
614  if (mult_frac(limit, 1024, max_beb_per1024) < device_pebs)
615  limit += 1;
616 
617  return limit;
618 }
619 
636 static int io_init(struct ubi_device *ubi, int max_beb_per1024)
637 {
638  dbg_gen("sizeof(struct ubi_ainf_peb) %zu", sizeof(struct ubi_ainf_peb));
639  dbg_gen("sizeof(struct ubi_wl_entry) %zu", sizeof(struct ubi_wl_entry));
640 
641  if (ubi->mtd->numeraseregions != 0) {
642  /*
643  * Some flashes have several erase regions. Different regions
644  * may have different eraseblock size and other
645  * characteristics. It looks like mostly multi-region flashes
646  * have one "main" region and one or more small regions to
647  * store boot loader code or boot parameters or whatever. I
648  * guess we should just pick the largest region. But this is
649  * not implemented.
650  */
651  ubi_err("multiple regions, not implemented");
652  return -EINVAL;
653  }
654 
655  if (ubi->vid_hdr_offset < 0)
656  return -EINVAL;
657 
658  /*
659  * Note, in this implementation we support MTD devices with 0x7FFFFFFF
660  * physical eraseblocks maximum.
661  */
662 
663  ubi->peb_size = ubi->mtd->erasesize;
664  ubi->peb_count = mtd_div_by_eb(ubi->mtd->size, ubi->mtd);
665  ubi->flash_size = ubi->mtd->size;
666 
667  if (mtd_can_have_bb(ubi->mtd)) {
668  ubi->bad_allowed = 1;
669  ubi->bad_peb_limit = get_bad_peb_limit(ubi, max_beb_per1024);
670  }
671 
672  if (ubi->mtd->type == MTD_NORFLASH) {
673  ubi_assert(ubi->mtd->writesize == 1);
674  ubi->nor_flash = 1;
675  }
676 
677  ubi->min_io_size = ubi->mtd->writesize;
678  ubi->hdrs_min_io_size = ubi->mtd->writesize >> ubi->mtd->subpage_sft;
679 
680  /*
681  * Make sure minimal I/O unit is power of 2. Note, there is no
682  * fundamental reason for this assumption. It is just an optimization
683  * which allows us to avoid costly division operations.
684  */
685  if (!is_power_of_2(ubi->min_io_size)) {
686  ubi_err("min. I/O unit (%d) is not power of 2",
687  ubi->min_io_size);
688  return -EINVAL;
689  }
690 
691  ubi_assert(ubi->hdrs_min_io_size > 0);
693  ubi_assert(ubi->min_io_size % ubi->hdrs_min_io_size == 0);
694 
695  ubi->max_write_size = ubi->mtd->writebufsize;
696  /*
697  * Maximum write size has to be greater or equivalent to min. I/O
698  * size, and be multiple of min. I/O size.
699  */
700  if (ubi->max_write_size < ubi->min_io_size ||
701  ubi->max_write_size % ubi->min_io_size ||
702  !is_power_of_2(ubi->max_write_size)) {
703  ubi_err("bad write buffer size %d for %d min. I/O unit",
704  ubi->max_write_size, ubi->min_io_size);
705  return -EINVAL;
706  }
707 
708  /* Calculate default aligned sizes of EC and VID headers */
711 
712  dbg_gen("min_io_size %d", ubi->min_io_size);
713  dbg_gen("max_write_size %d", ubi->max_write_size);
714  dbg_gen("hdrs_min_io_size %d", ubi->hdrs_min_io_size);
715  dbg_gen("ec_hdr_alsize %d", ubi->ec_hdr_alsize);
716  dbg_gen("vid_hdr_alsize %d", ubi->vid_hdr_alsize);
717 
718  if (ubi->vid_hdr_offset == 0)
719  /* Default offset */
720  ubi->vid_hdr_offset = ubi->vid_hdr_aloffset =
721  ubi->ec_hdr_alsize;
722  else {
723  ubi->vid_hdr_aloffset = ubi->vid_hdr_offset &
724  ~(ubi->hdrs_min_io_size - 1);
725  ubi->vid_hdr_shift = ubi->vid_hdr_offset -
726  ubi->vid_hdr_aloffset;
727  }
728 
729  /* Similar for the data offset */
731  ubi->leb_start = ALIGN(ubi->leb_start, ubi->min_io_size);
732 
733  dbg_gen("vid_hdr_offset %d", ubi->vid_hdr_offset);
734  dbg_gen("vid_hdr_aloffset %d", ubi->vid_hdr_aloffset);
735  dbg_gen("vid_hdr_shift %d", ubi->vid_hdr_shift);
736  dbg_gen("leb_start %d", ubi->leb_start);
737 
738  /* The shift must be aligned to 32-bit boundary */
739  if (ubi->vid_hdr_shift % 4) {
740  ubi_err("unaligned VID header shift %d",
741  ubi->vid_hdr_shift);
742  return -EINVAL;
743  }
744 
745  /* Check sanity */
746  if (ubi->vid_hdr_offset < UBI_EC_HDR_SIZE ||
747  ubi->leb_start < ubi->vid_hdr_offset + UBI_VID_HDR_SIZE ||
748  ubi->leb_start > ubi->peb_size - UBI_VID_HDR_SIZE ||
749  ubi->leb_start & (ubi->min_io_size - 1)) {
750  ubi_err("bad VID header (%d) or data offsets (%d)",
751  ubi->vid_hdr_offset, ubi->leb_start);
752  return -EINVAL;
753  }
754 
755  /*
756  * Set maximum amount of physical erroneous eraseblocks to be 10%.
757  * Erroneous PEB are those which have read errors.
758  */
759  ubi->max_erroneous = ubi->peb_count / 10;
760  if (ubi->max_erroneous < 16)
761  ubi->max_erroneous = 16;
762  dbg_gen("max_erroneous %d", ubi->max_erroneous);
763 
764  /*
765  * It may happen that EC and VID headers are situated in one minimal
766  * I/O unit. In this case we can only accept this UBI image in
767  * read-only mode.
768  */
769  if (ubi->vid_hdr_offset + UBI_VID_HDR_SIZE <= ubi->hdrs_min_io_size) {
770  ubi_warn("EC and VID headers are in the same minimal I/O unit, switch to read-only mode");
771  ubi->ro_mode = 1;
772  }
773 
774  ubi->leb_size = ubi->peb_size - ubi->leb_start;
775 
776  if (!(ubi->mtd->flags & MTD_WRITEABLE)) {
777  ubi_msg("MTD device %d is write-protected, attach in read-only mode",
778  ubi->mtd->index);
779  ubi->ro_mode = 1;
780  }
781 
782  /*
783  * Note, ideally, we have to initialize @ubi->bad_peb_count here. But
784  * unfortunately, MTD does not provide this information. We should loop
785  * over all physical eraseblocks and invoke mtd->block_is_bad() for
786  * each physical eraseblock. So, we leave @ubi->bad_peb_count
787  * uninitialized so far.
788  */
789 
790  return 0;
791 }
792 
803 static int autoresize(struct ubi_device *ubi, int vol_id)
804 {
805  struct ubi_volume_desc desc;
806  struct ubi_volume *vol = ubi->volumes[vol_id];
807  int err, old_reserved_pebs = vol->reserved_pebs;
808 
809  if (ubi->ro_mode) {
810  ubi_warn("skip auto-resize because of R/O mode");
811  return 0;
812  }
813 
814  /*
815  * Clear the auto-resize flag in the volume in-memory copy of the
816  * volume table, and 'ubi_resize_volume()' will propagate this change
817  * to the flash.
818  */
819  ubi->vtbl[vol_id].flags &= ~UBI_VTBL_AUTORESIZE_FLG;
820 
821  if (ubi->avail_pebs == 0) {
822  struct ubi_vtbl_record vtbl_rec;
823 
824  /*
825  * No available PEBs to re-size the volume, clear the flag on
826  * flash and exit.
827  */
828  memcpy(&vtbl_rec, &ubi->vtbl[vol_id],
829  sizeof(struct ubi_vtbl_record));
830  err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
831  if (err)
832  ubi_err("cannot clean auto-resize flag for volume %d",
833  vol_id);
834  } else {
835  desc.vol = vol;
836  err = ubi_resize_volume(&desc,
837  old_reserved_pebs + ubi->avail_pebs);
838  if (err)
839  ubi_err("cannot auto-resize volume %d", vol_id);
840  }
841 
842  if (err)
843  return err;
844 
845  ubi_msg("volume %d (\"%s\") re-sized from %d to %d LEBs", vol_id,
846  vol->name, old_reserved_pebs, vol->reserved_pebs);
847  return 0;
848 }
849 
866 int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
867  int vid_hdr_offset, int max_beb_per1024)
868 {
869  struct ubi_device *ubi;
870  int i, err, ref = 0;
871 
872  if (max_beb_per1024 < 0 || max_beb_per1024 > MAX_MTD_UBI_BEB_LIMIT)
873  return -EINVAL;
874 
875  if (!max_beb_per1024)
876  max_beb_per1024 = CONFIG_MTD_UBI_BEB_LIMIT;
877 
878  /*
879  * Check if we already have the same MTD device attached.
880  *
881  * Note, this function assumes that UBI devices creations and deletions
882  * are serialized, so it does not take the &ubi_devices_lock.
883  */
884  for (i = 0; i < UBI_MAX_DEVICES; i++) {
885  ubi = ubi_devices[i];
886  if (ubi && mtd->index == ubi->mtd->index) {
887  ubi_err("mtd%d is already attached to ubi%d",
888  mtd->index, i);
889  return -EEXIST;
890  }
891  }
892 
893  /*
894  * Make sure this MTD device is not emulated on top of an UBI volume
895  * already. Well, generally this recursion works fine, but there are
896  * different problems like the UBI module takes a reference to itself
897  * by attaching (and thus, opening) the emulated MTD device. This
898  * results in inability to unload the module. And in general it makes
899  * no sense to attach emulated MTD devices, so we prohibit this.
900  */
901  if (mtd->type == MTD_UBIVOLUME) {
902  ubi_err("refuse attaching mtd%d - it is already emulated on top of UBI",
903  mtd->index);
904  return -EINVAL;
905  }
906 
907  if (ubi_num == UBI_DEV_NUM_AUTO) {
908  /* Search for an empty slot in the @ubi_devices array */
909  for (ubi_num = 0; ubi_num < UBI_MAX_DEVICES; ubi_num++)
910  if (!ubi_devices[ubi_num])
911  break;
912  if (ubi_num == UBI_MAX_DEVICES) {
913  ubi_err("only %d UBI devices may be created",
914  UBI_MAX_DEVICES);
915  return -ENFILE;
916  }
917  } else {
918  if (ubi_num >= UBI_MAX_DEVICES)
919  return -EINVAL;
920 
921  /* Make sure ubi_num is not busy */
922  if (ubi_devices[ubi_num]) {
923  ubi_err("ubi%d already exists", ubi_num);
924  return -EEXIST;
925  }
926  }
927 
928  ubi = kzalloc(sizeof(struct ubi_device), GFP_KERNEL);
929  if (!ubi)
930  return -ENOMEM;
931 
932  ubi->mtd = mtd;
933  ubi->ubi_num = ubi_num;
935  ubi->autoresize_vol_id = -1;
936 
937 #ifdef CONFIG_MTD_UBI_FASTMAP
938  ubi->fm_pool.used = ubi->fm_pool.size = 0;
939  ubi->fm_wl_pool.used = ubi->fm_wl_pool.size = 0;
940 
941  /*
942  * fm_pool.max_size is 5% of the total number of PEBs but it's also
943  * between UBI_FM_MAX_POOL_SIZE and UBI_FM_MIN_POOL_SIZE.
944  */
945  ubi->fm_pool.max_size = min(((int)mtd_div_by_eb(ubi->mtd->size,
946  ubi->mtd) / 100) * 5, UBI_FM_MAX_POOL_SIZE);
947  if (ubi->fm_pool.max_size < UBI_FM_MIN_POOL_SIZE)
948  ubi->fm_pool.max_size = UBI_FM_MIN_POOL_SIZE;
949 
950  ubi->fm_wl_pool.max_size = UBI_FM_WL_POOL_SIZE;
951  ubi->fm_disabled = !fm_autoconvert;
952 
953  if (!ubi->fm_disabled && (int)mtd_div_by_eb(ubi->mtd->size, ubi->mtd)
954  <= UBI_FM_MAX_START) {
955  ubi_err("More than %i PEBs are needed for fastmap, sorry.",
957  ubi->fm_disabled = 1;
958  }
959 
960  ubi_msg("default fastmap pool size: %d", ubi->fm_pool.max_size);
961  ubi_msg("default fastmap WL pool size: %d", ubi->fm_wl_pool.max_size);
962 #else
963  ubi->fm_disabled = 1;
964 #endif
965  mutex_init(&ubi->buf_mutex);
966  mutex_init(&ubi->ckvol_mutex);
967  mutex_init(&ubi->device_mutex);
969  mutex_init(&ubi->fm_mutex);
970  init_rwsem(&ubi->fm_sem);
971 
972  ubi_msg("attaching mtd%d to ubi%d", mtd->index, ubi_num);
973 
974  err = io_init(ubi, max_beb_per1024);
975  if (err)
976  goto out_free;
977 
978  err = -ENOMEM;
979  ubi->peb_buf = vmalloc(ubi->peb_size);
980  if (!ubi->peb_buf)
981  goto out_free;
982 
983 #ifdef CONFIG_MTD_UBI_FASTMAP
984  ubi->fm_size = ubi_calc_fm_size(ubi);
985  ubi->fm_buf = vzalloc(ubi->fm_size);
986  if (!ubi->fm_buf)
987  goto out_free;
988 #endif
989  err = ubi_debugging_init_dev(ubi);
990  if (err)
991  goto out_free;
992 
993  err = ubi_attach(ubi, 0);
994  if (err) {
995  ubi_err("failed to attach mtd%d, error %d", mtd->index, err);
996  goto out_debugging;
997  }
998 
999  if (ubi->autoresize_vol_id != -1) {
1000  err = autoresize(ubi, ubi->autoresize_vol_id);
1001  if (err)
1002  goto out_detach;
1003  }
1004 
1005  err = uif_init(ubi, &ref);
1006  if (err)
1007  goto out_detach;
1008 
1009  err = ubi_debugfs_init_dev(ubi);
1010  if (err)
1011  goto out_uif;
1012 
1013  ubi->bgt_thread = kthread_create(ubi_thread, ubi, ubi->bgt_name);
1014  if (IS_ERR(ubi->bgt_thread)) {
1015  err = PTR_ERR(ubi->bgt_thread);
1016  ubi_err("cannot spawn \"%s\", error %d", ubi->bgt_name,
1017  err);
1018  goto out_debugfs;
1019  }
1020 
1021  ubi_msg("attached mtd%d (name \"%s\", size %llu MiB) to ubi%d",
1022  mtd->index, mtd->name, ubi->flash_size >> 20, ubi_num);
1023  ubi_msg("PEB size: %d bytes (%d KiB), LEB size: %d bytes",
1024  ubi->peb_size, ubi->peb_size >> 10, ubi->leb_size);
1025  ubi_msg("min./max. I/O unit sizes: %d/%d, sub-page size %d",
1026  ubi->min_io_size, ubi->max_write_size, ubi->hdrs_min_io_size);
1027  ubi_msg("VID header offset: %d (aligned %d), data offset: %d",
1028  ubi->vid_hdr_offset, ubi->vid_hdr_aloffset, ubi->leb_start);
1029  ubi_msg("good PEBs: %d, bad PEBs: %d, corrupted PEBs: %d",
1030  ubi->good_peb_count, ubi->bad_peb_count, ubi->corr_peb_count);
1031  ubi_msg("user volume: %d, internal volumes: %d, max. volumes count: %d",
1033  ubi->vtbl_slots);
1034  ubi_msg("max/mean erase counter: %d/%d, WL threshold: %d, image sequence number: %u",
1035  ubi->max_ec, ubi->mean_ec, CONFIG_MTD_UBI_WL_THRESHOLD,
1036  ubi->image_seq);
1037  ubi_msg("available PEBs: %d, total reserved PEBs: %d, PEBs reserved for bad PEB handling: %d",
1038  ubi->avail_pebs, ubi->rsvd_pebs, ubi->beb_rsvd_pebs);
1039 
1040  /*
1041  * The below lock makes sure we do not race with 'ubi_thread()' which
1042  * checks @ubi->thread_enabled. Otherwise we may fail to wake it up.
1043  */
1044  spin_lock(&ubi->wl_lock);
1045  ubi->thread_enabled = 1;
1047  spin_unlock(&ubi->wl_lock);
1048 
1049  ubi_devices[ubi_num] = ubi;
1051  return ubi_num;
1052 
1053 out_debugfs:
1054  ubi_debugfs_exit_dev(ubi);
1055 out_uif:
1056  get_device(&ubi->dev);
1057  ubi_assert(ref);
1058  uif_close(ubi);
1059 out_detach:
1060  ubi_wl_close(ubi);
1062  vfree(ubi->vtbl);
1063 out_debugging:
1065 out_free:
1066  vfree(ubi->peb_buf);
1067  vfree(ubi->fm_buf);
1068  if (ref)
1069  put_device(&ubi->dev);
1070  else
1071  kfree(ubi);
1072  return err;
1073 }
1074 
1088 int ubi_detach_mtd_dev(int ubi_num, int anyway)
1089 {
1090  struct ubi_device *ubi;
1091 
1092  if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES)
1093  return -EINVAL;
1094 
1095  ubi = ubi_get_device(ubi_num);
1096  if (!ubi)
1097  return -EINVAL;
1098 
1099  spin_lock(&ubi_devices_lock);
1100  put_device(&ubi->dev);
1101  ubi->ref_count -= 1;
1102  if (ubi->ref_count) {
1103  if (!anyway) {
1104  spin_unlock(&ubi_devices_lock);
1105  return -EBUSY;
1106  }
1107  /* This may only happen if there is a bug */
1108  ubi_err("%s reference count %d, destroy anyway",
1109  ubi->ubi_name, ubi->ref_count);
1110  }
1111  ubi_devices[ubi_num] = NULL;
1112  spin_unlock(&ubi_devices_lock);
1113 
1114  ubi_assert(ubi_num == ubi->ubi_num);
1116  ubi_msg("detaching mtd%d from ubi%d", ubi->mtd->index, ubi_num);
1117 #ifdef CONFIG_MTD_UBI_FASTMAP
1118  /* If we don't write a new fastmap at detach time we lose all
1119  * EC updates that have been made since the last written fastmap. */
1120  ubi_update_fastmap(ubi);
1121 #endif
1122  /*
1123  * Before freeing anything, we have to stop the background thread to
1124  * prevent it from doing anything on this device while we are freeing.
1125  */
1126  if (ubi->bgt_thread)
1127  kthread_stop(ubi->bgt_thread);
1128 
1129  /*
1130  * Get a reference to the device in order to prevent 'dev_release()'
1131  * from freeing the @ubi object.
1132  */
1133  get_device(&ubi->dev);
1134 
1135  ubi_debugfs_exit_dev(ubi);
1136  uif_close(ubi);
1137 
1138  ubi_wl_close(ubi);
1140  vfree(ubi->vtbl);
1141  put_mtd_device(ubi->mtd);
1143  vfree(ubi->peb_buf);
1144  vfree(ubi->fm_buf);
1145  ubi_msg("mtd%d is detached from ubi%d", ubi->mtd->index, ubi->ubi_num);
1146  put_device(&ubi->dev);
1147  return 0;
1148 }
1149 
1158 static struct mtd_info * __init open_mtd_by_chdev(const char *mtd_dev)
1159 {
1160  int err, major, minor, mode;
1161  struct path path;
1162 
1163  /* Probably this is an MTD character device node path */
1164  err = kern_path(mtd_dev, LOOKUP_FOLLOW, &path);
1165  if (err)
1166  return ERR_PTR(err);
1167 
1168  /* MTD device number is defined by the major / minor numbers */
1169  major = imajor(path.dentry->d_inode);
1170  minor = iminor(path.dentry->d_inode);
1171  mode = path.dentry->d_inode->i_mode;
1172  path_put(&path);
1173  if (major != MTD_CHAR_MAJOR || !S_ISCHR(mode))
1174  return ERR_PTR(-EINVAL);
1175 
1176  if (minor & 1)
1177  /*
1178  * Just do not think the "/dev/mtdrX" devices support is need,
1179  * so do not support them to avoid doing extra work.
1180  */
1181  return ERR_PTR(-EINVAL);
1182 
1183  return get_mtd_device(NULL, minor / 2);
1184 }
1185 
1196 static struct mtd_info * __init open_mtd_device(const char *mtd_dev)
1197 {
1198  struct mtd_info *mtd;
1199  int mtd_num;
1200  char *endp;
1201 
1202  mtd_num = simple_strtoul(mtd_dev, &endp, 0);
1203  if (*endp != '\0' || mtd_dev == endp) {
1204  /*
1205  * This does not look like an ASCII integer, probably this is
1206  * MTD device name.
1207  */
1208  mtd = get_mtd_device_nm(mtd_dev);
1209  if (IS_ERR(mtd) && PTR_ERR(mtd) == -ENODEV)
1210  /* Probably this is an MTD character device node path */
1211  mtd = open_mtd_by_chdev(mtd_dev);
1212  } else
1213  mtd = get_mtd_device(NULL, mtd_num);
1214 
1215  return mtd;
1216 }
1217 
1218 static int __init ubi_init(void)
1219 {
1220  int err, i, k;
1221 
1222  /* Ensure that EC and VID headers have correct size */
1223  BUILD_BUG_ON(sizeof(struct ubi_ec_hdr) != 64);
1224  BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64);
1225 
1226  if (mtd_devs > UBI_MAX_DEVICES) {
1227  ubi_err("too many MTD devices, maximum is %d", UBI_MAX_DEVICES);
1228  return -EINVAL;
1229  }
1230 
1231  /* Create base sysfs directory and sysfs files */
1232  ubi_class = class_create(THIS_MODULE, UBI_NAME_STR);
1233  if (IS_ERR(ubi_class)) {
1234  err = PTR_ERR(ubi_class);
1235  ubi_err("cannot create UBI class");
1236  goto out;
1237  }
1238 
1239  err = class_create_file(ubi_class, &ubi_version);
1240  if (err) {
1241  ubi_err("cannot create sysfs file");
1242  goto out_class;
1243  }
1244 
1245  err = misc_register(&ubi_ctrl_cdev);
1246  if (err) {
1247  ubi_err("cannot register device");
1248  goto out_version;
1249  }
1250 
1251  ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab",
1252  sizeof(struct ubi_wl_entry),
1253  0, 0, NULL);
1254  if (!ubi_wl_entry_slab)
1255  goto out_dev_unreg;
1256 
1257  err = ubi_debugfs_init();
1258  if (err)
1259  goto out_slab;
1260 
1261 
1262  /* Attach MTD devices */
1263  for (i = 0; i < mtd_devs; i++) {
1264  struct mtd_dev_param *p = &mtd_dev_param[i];
1265  struct mtd_info *mtd;
1266 
1267  cond_resched();
1268 
1269  mtd = open_mtd_device(p->name);
1270  if (IS_ERR(mtd)) {
1271  err = PTR_ERR(mtd);
1272  goto out_detach;
1273  }
1274 
1275  mutex_lock(&ubi_devices_mutex);
1277  p->vid_hdr_offs, p->max_beb_per1024);
1278  mutex_unlock(&ubi_devices_mutex);
1279  if (err < 0) {
1280  ubi_err("cannot attach mtd%d", mtd->index);
1281  put_mtd_device(mtd);
1282 
1283  /*
1284  * Originally UBI stopped initializing on any error.
1285  * However, later on it was found out that this
1286  * behavior is not very good when UBI is compiled into
1287  * the kernel and the MTD devices to attach are passed
1288  * through the command line. Indeed, UBI failure
1289  * stopped whole boot sequence.
1290  *
1291  * To fix this, we changed the behavior for the
1292  * non-module case, but preserved the old behavior for
1293  * the module case, just for compatibility. This is a
1294  * little inconsistent, though.
1295  */
1296  if (ubi_is_module())
1297  goto out_detach;
1298  }
1299  }
1300 
1301  return 0;
1302 
1303 out_detach:
1304  for (k = 0; k < i; k++)
1305  if (ubi_devices[k]) {
1306  mutex_lock(&ubi_devices_mutex);
1307  ubi_detach_mtd_dev(ubi_devices[k]->ubi_num, 1);
1308  mutex_unlock(&ubi_devices_mutex);
1309  }
1310  ubi_debugfs_exit();
1311 out_slab:
1312  kmem_cache_destroy(ubi_wl_entry_slab);
1313 out_dev_unreg:
1314  misc_deregister(&ubi_ctrl_cdev);
1315 out_version:
1316  class_remove_file(ubi_class, &ubi_version);
1317 out_class:
1318  class_destroy(ubi_class);
1319 out:
1320  ubi_err("UBI error: cannot initialize UBI, error %d", err);
1321  return err;
1322 }
1323 late_initcall(ubi_init);
1324 
1325 static void __exit ubi_exit(void)
1326 {
1327  int i;
1328 
1329  for (i = 0; i < UBI_MAX_DEVICES; i++)
1330  if (ubi_devices[i]) {
1331  mutex_lock(&ubi_devices_mutex);
1332  ubi_detach_mtd_dev(ubi_devices[i]->ubi_num, 1);
1333  mutex_unlock(&ubi_devices_mutex);
1334  }
1335  ubi_debugfs_exit();
1336  kmem_cache_destroy(ubi_wl_entry_slab);
1337  misc_deregister(&ubi_ctrl_cdev);
1338  class_remove_file(ubi_class, &ubi_version);
1339  class_destroy(ubi_class);
1340 }
1341 module_exit(ubi_exit);
1342 
1350 static int __init bytes_str_to_int(const char *str)
1351 {
1352  char *endp;
1353  unsigned long result;
1354 
1355  result = simple_strtoul(str, &endp, 0);
1356  if (str == endp || result >= INT_MAX) {
1357  ubi_err("UBI error: incorrect bytes count: \"%s\"\n", str);
1358  return -EINVAL;
1359  }
1360 
1361  switch (*endp) {
1362  case 'G':
1363  result *= 1024;
1364  case 'M':
1365  result *= 1024;
1366  case 'K':
1367  result *= 1024;
1368  if (endp[1] == 'i' && endp[2] == 'B')
1369  endp += 2;
1370  case '\0':
1371  break;
1372  default:
1373  ubi_err("UBI error: incorrect bytes count: \"%s\"\n", str);
1374  return -EINVAL;
1375  }
1376 
1377  return result;
1378 }
1379 
1388 static int __init ubi_mtd_param_parse(const char *val, struct kernel_param *kp)
1389 {
1390  int i, len;
1391  struct mtd_dev_param *p;
1392  char buf[MTD_PARAM_LEN_MAX];
1393  char *pbuf = &buf[0];
1394  char *tokens[MTD_PARAM_MAX_COUNT];
1395 
1396  if (!val)
1397  return -EINVAL;
1398 
1399  if (mtd_devs == UBI_MAX_DEVICES) {
1400  ubi_err("UBI error: too many parameters, max. is %d\n",
1401  UBI_MAX_DEVICES);
1402  return -EINVAL;
1403  }
1404 
1405  len = strnlen(val, MTD_PARAM_LEN_MAX);
1406  if (len == MTD_PARAM_LEN_MAX) {
1407  ubi_err("UBI error: parameter \"%s\" is too long, max. is %d\n",
1408  val, MTD_PARAM_LEN_MAX);
1409  return -EINVAL;
1410  }
1411 
1412  if (len == 0) {
1413  pr_warn("UBI warning: empty 'mtd=' parameter - ignored\n");
1414  return 0;
1415  }
1416 
1417  strcpy(buf, val);
1418 
1419  /* Get rid of the final newline */
1420  if (buf[len - 1] == '\n')
1421  buf[len - 1] = '\0';
1422 
1423  for (i = 0; i < MTD_PARAM_MAX_COUNT; i++)
1424  tokens[i] = strsep(&pbuf, ",");
1425 
1426  if (pbuf) {
1427  ubi_err("UBI error: too many arguments at \"%s\"\n", val);
1428  return -EINVAL;
1429  }
1430 
1431  p = &mtd_dev_param[mtd_devs];
1432  strcpy(&p->name[0], tokens[0]);
1433 
1434  if (tokens[1])
1435  p->vid_hdr_offs = bytes_str_to_int(tokens[1]);
1436 
1437  if (p->vid_hdr_offs < 0)
1438  return p->vid_hdr_offs;
1439 
1440  if (tokens[2]) {
1441  int err = kstrtoint(tokens[2], 10, &p->max_beb_per1024);
1442 
1443  if (err) {
1444  ubi_err("UBI error: bad value for max_beb_per1024 parameter: %s",
1445  tokens[2]);
1446  return -EINVAL;
1447  }
1448  }
1449 
1450  mtd_devs += 1;
1451  return 0;
1452 }
1453 
1454 module_param_call(mtd, ubi_mtd_param_parse, NULL, NULL, 000);
1455 MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: mtd=<name|num|path>[,<vid_hdr_offs>[,max_beb_per1024]].\n"
1456  "Multiple \"mtd\" parameters may be specified.\n"
1457  "MTD devices may be specified by their number, name, or path to the MTD character device node.\n"
1458  "Optional \"vid_hdr_offs\" parameter specifies UBI VID header position to be used by UBI. (default value if 0)\n"
1459  "Optional \"max_beb_per1024\" parameter specifies the maximum expected bad eraseblock per 1024 eraseblocks. (default value ("
1460  __stringify(CONFIG_MTD_UBI_BEB_LIMIT) ") if 0)\n"
1461  "\n"
1462  "Example 1: mtd=/dev/mtd0 - attach MTD device /dev/mtd0.\n"
1463  "Example 2: mtd=content,1984 mtd=4 - attach MTD device with name \"content\" using VID header offset 1984, and MTD device number 4 with default VID header offset.\n"
1464  "Example 3: mtd=/dev/mtd1,0,25 - attach MTD device /dev/mtd1 using default VID header offset and reserve 25*nand_size_in_blocks/1024 erase blocks for bad block handling.\n"
1465  "\t(e.g. if the NAND *chipset* has 4096 PEB, 100 will be reserved for this UBI device).");
1466 #ifdef CONFIG_MTD_UBI_FASTMAP
1467 module_param(fm_autoconvert, bool, 0644);
1468 MODULE_PARM_DESC(fm_autoconvert, "Set this parameter to enable fastmap automatically on images without a fastmap.");
1469 #endif
1471 MODULE_DESCRIPTION("UBI - Unsorted Block Images");
1472 MODULE_AUTHOR("Artem Bityutskiy");
1473 MODULE_LICENSE("GPL");