blob: 423d479152f367fdb25d7fec024fe23421d1dd53 [file] [log] [blame]
Kyungmin Park2d262c42008-11-19 16:26:54 +01001/*
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/* This file mostly implements UBI kernel API functions */
22
23#ifdef UBI_LINUX
24#include <linux/module.h>
25#include <linux/err.h>
26#include <asm/div64.h>
27#endif
28
29#include <ubi_uboot.h>
30#include "ubi.h"
31
32/**
33 * ubi_get_device_info - get information about UBI device.
34 * @ubi_num: UBI device number
35 * @di: the information is stored here
36 *
37 * This function returns %0 in case of success, %-EINVAL if the UBI device
38 * number is invalid, and %-ENODEV if there is no such UBI device.
39 */
40int ubi_get_device_info(int ubi_num, struct ubi_device_info *di)
41{
42 struct ubi_device *ubi;
43
44 if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES)
45 return -EINVAL;
46
47 ubi = ubi_get_device(ubi_num);
48 if (!ubi)
49 return -ENODEV;
50
51 di->ubi_num = ubi->ubi_num;
52 di->leb_size = ubi->leb_size;
53 di->min_io_size = ubi->min_io_size;
54 di->ro_mode = ubi->ro_mode;
55 di->cdev = ubi->cdev.dev;
56
57 ubi_put_device(ubi);
58 return 0;
59}
60EXPORT_SYMBOL_GPL(ubi_get_device_info);
61
62/**
63 * ubi_get_volume_info - get information about UBI volume.
64 * @desc: volume descriptor
65 * @vi: the information is stored here
66 */
67void ubi_get_volume_info(struct ubi_volume_desc *desc,
68 struct ubi_volume_info *vi)
69{
70 const struct ubi_volume *vol = desc->vol;
71 const struct ubi_device *ubi = vol->ubi;
72
73 vi->vol_id = vol->vol_id;
74 vi->ubi_num = ubi->ubi_num;
75 vi->size = vol->reserved_pebs;
76 vi->used_bytes = vol->used_bytes;
77 vi->vol_type = vol->vol_type;
78 vi->corrupted = vol->corrupted;
79 vi->upd_marker = vol->upd_marker;
80 vi->alignment = vol->alignment;
81 vi->usable_leb_size = vol->usable_leb_size;
82 vi->name_len = vol->name_len;
83 vi->name = vol->name;
84 vi->cdev = vol->cdev.dev;
85}
86EXPORT_SYMBOL_GPL(ubi_get_volume_info);
87
88/**
89 * ubi_open_volume - open UBI volume.
90 * @ubi_num: UBI device number
91 * @vol_id: volume ID
92 * @mode: open mode
93 *
94 * The @mode parameter specifies if the volume should be opened in read-only
95 * mode, read-write mode, or exclusive mode. The exclusive mode guarantees that
96 * nobody else will be able to open this volume. UBI allows to have many volume
97 * readers and one writer at a time.
98 *
99 * If a static volume is being opened for the first time since boot, it will be
100 * checked by this function, which means it will be fully read and the CRC
101 * checksum of each logical eraseblock will be checked.
102 *
103 * This function returns volume descriptor in case of success and a negative
104 * error code in case of failure.
105 */
106struct ubi_volume_desc *ubi_open_volume(int ubi_num, int vol_id, int mode)
107{
108 int err;
109 struct ubi_volume_desc *desc;
110 struct ubi_device *ubi;
111 struct ubi_volume *vol;
112
113 dbg_msg("open device %d volume %d, mode %d", ubi_num, vol_id, mode);
114
115 if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES)
116 return ERR_PTR(-EINVAL);
117
118 if (mode != UBI_READONLY && mode != UBI_READWRITE &&
119 mode != UBI_EXCLUSIVE)
120 return ERR_PTR(-EINVAL);
121
122 /*
123 * First of all, we have to get the UBI device to prevent its removal.
124 */
125 ubi = ubi_get_device(ubi_num);
126 if (!ubi)
127 return ERR_PTR(-ENODEV);
128
129 if (vol_id < 0 || vol_id >= ubi->vtbl_slots) {
130 err = -EINVAL;
131 goto out_put_ubi;
132 }
133
134 desc = kmalloc(sizeof(struct ubi_volume_desc), GFP_KERNEL);
135 if (!desc) {
136 err = -ENOMEM;
137 goto out_put_ubi;
138 }
139
140 err = -ENODEV;
141 if (!try_module_get(THIS_MODULE))
142 goto out_free;
143
144 spin_lock(&ubi->volumes_lock);
145 vol = ubi->volumes[vol_id];
146 if (!vol)
147 goto out_unlock;
148
149 err = -EBUSY;
150 switch (mode) {
151 case UBI_READONLY:
152 if (vol->exclusive)
153 goto out_unlock;
154 vol->readers += 1;
155 break;
156
157 case UBI_READWRITE:
158 if (vol->exclusive || vol->writers > 0)
159 goto out_unlock;
160 vol->writers += 1;
161 break;
162
163 case UBI_EXCLUSIVE:
164 if (vol->exclusive || vol->writers || vol->readers)
165 goto out_unlock;
166 vol->exclusive = 1;
167 break;
168 }
169 get_device(&vol->dev);
170 vol->ref_count += 1;
171 spin_unlock(&ubi->volumes_lock);
172
173 desc->vol = vol;
174 desc->mode = mode;
175
176 mutex_lock(&ubi->ckvol_mutex);
177 if (!vol->checked) {
178 /* This is the first open - check the volume */
179 err = ubi_check_volume(ubi, vol_id);
180 if (err < 0) {
181 mutex_unlock(&ubi->ckvol_mutex);
182 ubi_close_volume(desc);
183 return ERR_PTR(err);
184 }
185 if (err == 1) {
186 ubi_warn("volume %d on UBI device %d is corrupted",
187 vol_id, ubi->ubi_num);
188 vol->corrupted = 1;
189 }
190 vol->checked = 1;
191 }
192 mutex_unlock(&ubi->ckvol_mutex);
193
194 return desc;
195
196out_unlock:
197 spin_unlock(&ubi->volumes_lock);
198 module_put(THIS_MODULE);
199out_free:
200 kfree(desc);
201out_put_ubi:
202 ubi_put_device(ubi);
203 return ERR_PTR(err);
204}
205EXPORT_SYMBOL_GPL(ubi_open_volume);
206
207/**
208 * ubi_open_volume_nm - open UBI volume by name.
209 * @ubi_num: UBI device number
210 * @name: volume name
211 * @mode: open mode
212 *
213 * This function is similar to 'ubi_open_volume()', but opens a volume by name.
214 */
215struct ubi_volume_desc *ubi_open_volume_nm(int ubi_num, const char *name,
216 int mode)
217{
218 int i, vol_id = -1, len;
219 struct ubi_device *ubi;
220 struct ubi_volume_desc *ret;
221
222 dbg_msg("open volume %s, mode %d", name, mode);
223
224 if (!name)
225 return ERR_PTR(-EINVAL);
226
227 len = strnlen(name, UBI_VOL_NAME_MAX + 1);
228 if (len > UBI_VOL_NAME_MAX)
229 return ERR_PTR(-EINVAL);
230
231 if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES)
232 return ERR_PTR(-EINVAL);
233
234 ubi = ubi_get_device(ubi_num);
235 if (!ubi)
236 return ERR_PTR(-ENODEV);
237
238 spin_lock(&ubi->volumes_lock);
239 /* Walk all volumes of this UBI device */
240 for (i = 0; i < ubi->vtbl_slots; i++) {
241 struct ubi_volume *vol = ubi->volumes[i];
242
243 if (vol && len == vol->name_len && !strcmp(name, vol->name)) {
244 vol_id = i;
245 break;
246 }
247 }
248 spin_unlock(&ubi->volumes_lock);
249
250 if (vol_id >= 0)
251 ret = ubi_open_volume(ubi_num, vol_id, mode);
252 else
253 ret = ERR_PTR(-ENODEV);
254
255 /*
256 * We should put the UBI device even in case of success, because
257 * 'ubi_open_volume()' took a reference as well.
258 */
259 ubi_put_device(ubi);
260 return ret;
261}
262EXPORT_SYMBOL_GPL(ubi_open_volume_nm);
263
264/**
265 * ubi_close_volume - close UBI volume.
266 * @desc: volume descriptor
267 */
268void ubi_close_volume(struct ubi_volume_desc *desc)
269{
270 struct ubi_volume *vol = desc->vol;
271 struct ubi_device *ubi = vol->ubi;
272
273 dbg_msg("close volume %d, mode %d", vol->vol_id, desc->mode);
274
275 spin_lock(&ubi->volumes_lock);
276 switch (desc->mode) {
277 case UBI_READONLY:
278 vol->readers -= 1;
279 break;
280 case UBI_READWRITE:
281 vol->writers -= 1;
282 break;
283 case UBI_EXCLUSIVE:
284 vol->exclusive = 0;
285 }
286 vol->ref_count -= 1;
287 spin_unlock(&ubi->volumes_lock);
288
289 kfree(desc);
290 put_device(&vol->dev);
291 ubi_put_device(ubi);
292 module_put(THIS_MODULE);
293}
294EXPORT_SYMBOL_GPL(ubi_close_volume);
295
296/**
297 * ubi_leb_read - read data.
298 * @desc: volume descriptor
299 * @lnum: logical eraseblock number to read from
300 * @buf: buffer where to store the read data
301 * @offset: offset within the logical eraseblock to read from
302 * @len: how many bytes to read
303 * @check: whether UBI has to check the read data's CRC or not.
304 *
305 * This function reads data from offset @offset of logical eraseblock @lnum and
306 * stores the data at @buf. When reading from static volumes, @check specifies
307 * whether the data has to be checked or not. If yes, the whole logical
308 * eraseblock will be read and its CRC checksum will be checked (i.e., the CRC
309 * checksum is per-eraseblock). So checking may substantially slow down the
310 * read speed. The @check argument is ignored for dynamic volumes.
311 *
312 * In case of success, this function returns zero. In case of failure, this
313 * function returns a negative error code.
314 *
315 * %-EBADMSG error code is returned:
316 * o for both static and dynamic volumes if MTD driver has detected a data
317 * integrity problem (unrecoverable ECC checksum mismatch in case of NAND);
318 * o for static volumes in case of data CRC mismatch.
319 *
320 * If the volume is damaged because of an interrupted update this function just
321 * returns immediately with %-EBADF error code.
322 */
323int ubi_leb_read(struct ubi_volume_desc *desc, int lnum, char *buf, int offset,
324 int len, int check)
325{
326 struct ubi_volume *vol = desc->vol;
327 struct ubi_device *ubi = vol->ubi;
328 int err, vol_id = vol->vol_id;
329
330 dbg_msg("read %d bytes from LEB %d:%d:%d", len, vol_id, lnum, offset);
331
332 if (vol_id < 0 || vol_id >= ubi->vtbl_slots || lnum < 0 ||
333 lnum >= vol->used_ebs || offset < 0 || len < 0 ||
334 offset + len > vol->usable_leb_size)
335 return -EINVAL;
336
337 if (vol->vol_type == UBI_STATIC_VOLUME) {
338 if (vol->used_ebs == 0)
339 /* Empty static UBI volume */
340 return 0;
341 if (lnum == vol->used_ebs - 1 &&
342 offset + len > vol->last_eb_bytes)
343 return -EINVAL;
344 }
345
346 if (vol->upd_marker)
347 return -EBADF;
348 if (len == 0)
349 return 0;
350
351 err = ubi_eba_read_leb(ubi, vol, lnum, buf, offset, len, check);
352 if (err && err == -EBADMSG && vol->vol_type == UBI_STATIC_VOLUME) {
353 ubi_warn("mark volume %d as corrupted", vol_id);
354 vol->corrupted = 1;
355 }
356
357 return err;
358}
359EXPORT_SYMBOL_GPL(ubi_leb_read);
360
361/**
362 * ubi_leb_write - write data.
363 * @desc: volume descriptor
364 * @lnum: logical eraseblock number to write to
365 * @buf: data to write
366 * @offset: offset within the logical eraseblock where to write
367 * @len: how many bytes to write
368 * @dtype: expected data type
369 *
370 * This function writes @len bytes of data from @buf to offset @offset of
371 * logical eraseblock @lnum. The @dtype argument describes expected lifetime of
372 * the data.
373 *
374 * This function takes care of physical eraseblock write failures. If write to
375 * the physical eraseblock write operation fails, the logical eraseblock is
376 * re-mapped to another physical eraseblock, the data is recovered, and the
377 * write finishes. UBI has a pool of reserved physical eraseblocks for this.
378 *
379 * If all the data were successfully written, zero is returned. If an error
380 * occurred and UBI has not been able to recover from it, this function returns
381 * a negative error code. Note, in case of an error, it is possible that
382 * something was still written to the flash media, but that may be some
383 * garbage.
384 *
385 * If the volume is damaged because of an interrupted update this function just
386 * returns immediately with %-EBADF code.
387 */
388int ubi_leb_write(struct ubi_volume_desc *desc, int lnum, const void *buf,
389 int offset, int len, int dtype)
390{
391 struct ubi_volume *vol = desc->vol;
392 struct ubi_device *ubi = vol->ubi;
393 int vol_id = vol->vol_id;
394
395 dbg_msg("write %d bytes to LEB %d:%d:%d", len, vol_id, lnum, offset);
396
397 if (vol_id < 0 || vol_id >= ubi->vtbl_slots)
398 return -EINVAL;
399
400 if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME)
401 return -EROFS;
402
403 if (lnum < 0 || lnum >= vol->reserved_pebs || offset < 0 || len < 0 ||
404 offset + len > vol->usable_leb_size ||
405 offset & (ubi->min_io_size - 1) || len & (ubi->min_io_size - 1))
406 return -EINVAL;
407
408 if (dtype != UBI_LONGTERM && dtype != UBI_SHORTTERM &&
409 dtype != UBI_UNKNOWN)
410 return -EINVAL;
411
412 if (vol->upd_marker)
413 return -EBADF;
414
415 if (len == 0)
416 return 0;
417
418 return ubi_eba_write_leb(ubi, vol, lnum, buf, offset, len, dtype);
419}
420EXPORT_SYMBOL_GPL(ubi_leb_write);
421
422/*
423 * ubi_leb_change - change logical eraseblock atomically.
424 * @desc: volume descriptor
425 * @lnum: logical eraseblock number to change
426 * @buf: data to write
427 * @len: how many bytes to write
428 * @dtype: expected data type
429 *
430 * This function changes the contents of a logical eraseblock atomically. @buf
431 * has to contain new logical eraseblock data, and @len - the length of the
432 * data, which has to be aligned. The length may be shorter then the logical
433 * eraseblock size, ant the logical eraseblock may be appended to more times
434 * later on. This function guarantees that in case of an unclean reboot the old
435 * contents is preserved. Returns zero in case of success and a negative error
436 * code in case of failure.
437 */
438int ubi_leb_change(struct ubi_volume_desc *desc, int lnum, const void *buf,
439 int len, int dtype)
440{
441 struct ubi_volume *vol = desc->vol;
442 struct ubi_device *ubi = vol->ubi;
443 int vol_id = vol->vol_id;
444
445 dbg_msg("atomically write %d bytes to LEB %d:%d", len, vol_id, lnum);
446
447 if (vol_id < 0 || vol_id >= ubi->vtbl_slots)
448 return -EINVAL;
449
450 if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME)
451 return -EROFS;
452
453 if (lnum < 0 || lnum >= vol->reserved_pebs || len < 0 ||
454 len > vol->usable_leb_size || len & (ubi->min_io_size - 1))
455 return -EINVAL;
456
457 if (dtype != UBI_LONGTERM && dtype != UBI_SHORTTERM &&
458 dtype != UBI_UNKNOWN)
459 return -EINVAL;
460
461 if (vol->upd_marker)
462 return -EBADF;
463
464 if (len == 0)
465 return 0;
466
467 return ubi_eba_atomic_leb_change(ubi, vol, lnum, buf, len, dtype);
468}
469EXPORT_SYMBOL_GPL(ubi_leb_change);
470
471/**
472 * ubi_leb_erase - erase logical eraseblock.
473 * @desc: volume descriptor
474 * @lnum: logical eraseblock number
475 *
476 * This function un-maps logical eraseblock @lnum and synchronously erases the
477 * correspondent physical eraseblock. Returns zero in case of success and a
478 * negative error code in case of failure.
479 *
480 * If the volume is damaged because of an interrupted update this function just
481 * returns immediately with %-EBADF code.
482 */
483int ubi_leb_erase(struct ubi_volume_desc *desc, int lnum)
484{
485 struct ubi_volume *vol = desc->vol;
486 struct ubi_device *ubi = vol->ubi;
487 int err;
488
489 dbg_msg("erase LEB %d:%d", vol->vol_id, lnum);
490
491 if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME)
492 return -EROFS;
493
494 if (lnum < 0 || lnum >= vol->reserved_pebs)
495 return -EINVAL;
496
497 if (vol->upd_marker)
498 return -EBADF;
499
500 err = ubi_eba_unmap_leb(ubi, vol, lnum);
501 if (err)
502 return err;
503
504 return ubi_wl_flush(ubi);
505}
506EXPORT_SYMBOL_GPL(ubi_leb_erase);
507
508/**
509 * ubi_leb_unmap - un-map logical eraseblock.
510 * @desc: volume descriptor
511 * @lnum: logical eraseblock number
512 *
513 * This function un-maps logical eraseblock @lnum and schedules the
514 * corresponding physical eraseblock for erasure, so that it will eventually be
515 * physically erased in background. This operation is much faster then the
516 * erase operation.
517 *
518 * Unlike erase, the un-map operation does not guarantee that the logical
519 * eraseblock will contain all 0xFF bytes when UBI is initialized again. For
520 * example, if several logical eraseblocks are un-mapped, and an unclean reboot
521 * happens after this, the logical eraseblocks will not necessarily be
522 * un-mapped again when this MTD device is attached. They may actually be
523 * mapped to the same physical eraseblocks again. So, this function has to be
524 * used with care.
525 *
526 * In other words, when un-mapping a logical eraseblock, UBI does not store
527 * any information about this on the flash media, it just marks the logical
528 * eraseblock as "un-mapped" in RAM. If UBI is detached before the physical
529 * eraseblock is physically erased, it will be mapped again to the same logical
530 * eraseblock when the MTD device is attached again.
531 *
532 * The main and obvious use-case of this function is when the contents of a
533 * logical eraseblock has to be re-written. Then it is much more efficient to
534 * first un-map it, then write new data, rather then first erase it, then write
535 * new data. Note, once new data has been written to the logical eraseblock,
536 * UBI guarantees that the old contents has gone forever. In other words, if an
537 * unclean reboot happens after the logical eraseblock has been un-mapped and
538 * then written to, it will contain the last written data.
539 *
540 * This function returns zero in case of success and a negative error code in
541 * case of failure. If the volume is damaged because of an interrupted update
542 * this function just returns immediately with %-EBADF code.
543 */
544int ubi_leb_unmap(struct ubi_volume_desc *desc, int lnum)
545{
546 struct ubi_volume *vol = desc->vol;
547 struct ubi_device *ubi = vol->ubi;
548
549 dbg_msg("unmap LEB %d:%d", vol->vol_id, lnum);
550
551 if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME)
552 return -EROFS;
553
554 if (lnum < 0 || lnum >= vol->reserved_pebs)
555 return -EINVAL;
556
557 if (vol->upd_marker)
558 return -EBADF;
559
560 return ubi_eba_unmap_leb(ubi, vol, lnum);
561}
562EXPORT_SYMBOL_GPL(ubi_leb_unmap);
563
564/**
565 * ubi_leb_map - map logical erasblock to a physical eraseblock.
566 * @desc: volume descriptor
567 * @lnum: logical eraseblock number
568 * @dtype: expected data type
569 *
570 * This function maps an un-mapped logical eraseblock @lnum to a physical
571 * eraseblock. This means, that after a successfull invocation of this
572 * function the logical eraseblock @lnum will be empty (contain only %0xFF
573 * bytes) and be mapped to a physical eraseblock, even if an unclean reboot
574 * happens.
575 *
576 * This function returns zero in case of success, %-EBADF if the volume is
577 * damaged because of an interrupted update, %-EBADMSG if the logical
578 * eraseblock is already mapped, and other negative error codes in case of
579 * other failures.
580 */
581int ubi_leb_map(struct ubi_volume_desc *desc, int lnum, int dtype)
582{
583 struct ubi_volume *vol = desc->vol;
584 struct ubi_device *ubi = vol->ubi;
585
586 dbg_msg("unmap LEB %d:%d", vol->vol_id, lnum);
587
588 if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME)
589 return -EROFS;
590
591 if (lnum < 0 || lnum >= vol->reserved_pebs)
592 return -EINVAL;
593
594 if (dtype != UBI_LONGTERM && dtype != UBI_SHORTTERM &&
595 dtype != UBI_UNKNOWN)
596 return -EINVAL;
597
598 if (vol->upd_marker)
599 return -EBADF;
600
601 if (vol->eba_tbl[lnum] >= 0)
602 return -EBADMSG;
603
604 return ubi_eba_write_leb(ubi, vol, lnum, NULL, 0, 0, dtype);
605}
606EXPORT_SYMBOL_GPL(ubi_leb_map);
607
608/**
609 * ubi_is_mapped - check if logical eraseblock is mapped.
610 * @desc: volume descriptor
611 * @lnum: logical eraseblock number
612 *
613 * This function checks if logical eraseblock @lnum is mapped to a physical
614 * eraseblock. If a logical eraseblock is un-mapped, this does not necessarily
615 * mean it will still be un-mapped after the UBI device is re-attached. The
616 * logical eraseblock may become mapped to the physical eraseblock it was last
617 * mapped to.
618 *
619 * This function returns %1 if the LEB is mapped, %0 if not, and a negative
620 * error code in case of failure. If the volume is damaged because of an
621 * interrupted update this function just returns immediately with %-EBADF error
622 * code.
623 */
624int ubi_is_mapped(struct ubi_volume_desc *desc, int lnum)
625{
626 struct ubi_volume *vol = desc->vol;
627
628 dbg_msg("test LEB %d:%d", vol->vol_id, lnum);
629
630 if (lnum < 0 || lnum >= vol->reserved_pebs)
631 return -EINVAL;
632
633 if (vol->upd_marker)
634 return -EBADF;
635
636 return vol->eba_tbl[lnum] >= 0;
637}
638EXPORT_SYMBOL_GPL(ubi_is_mapped);