Commit | Line | Data |
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801c135c AB |
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 | /* This file mostly implements UBI kernel API functions */ | |
22 | ||
23 | #include <linux/module.h> | |
24 | #include <linux/err.h> | |
25 | #include <asm/div64.h> | |
26 | #include "ubi.h" | |
27 | ||
28 | /** | |
29 | * ubi_get_device_info - get information about UBI device. | |
30 | * @ubi_num: UBI device number | |
31 | * @di: the information is stored here | |
32 | * | |
e73f4459 AB |
33 | * This function returns %0 in case of success, %-EINVAL if the UBI device |
34 | * number is invalid, and %-ENODEV if there is no such UBI device. | |
801c135c AB |
35 | */ |
36 | int ubi_get_device_info(int ubi_num, struct ubi_device_info *di) | |
37 | { | |
e73f4459 AB |
38 | struct ubi_device *ubi; |
39 | ||
40 | if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES) | |
41 | return -EINVAL; | |
801c135c | 42 | |
e73f4459 AB |
43 | ubi = ubi_get_device(ubi_num); |
44 | if (!ubi) | |
801c135c | 45 | return -ENODEV; |
801c135c | 46 | |
801c135c AB |
47 | di->ubi_num = ubi->ubi_num; |
48 | di->leb_size = ubi->leb_size; | |
49 | di->min_io_size = ubi->min_io_size; | |
50 | di->ro_mode = ubi->ro_mode; | |
49dfc299 | 51 | di->cdev = ubi->cdev.dev; |
e73f4459 AB |
52 | |
53 | ubi_put_device(ubi); | |
801c135c AB |
54 | return 0; |
55 | } | |
56 | EXPORT_SYMBOL_GPL(ubi_get_device_info); | |
57 | ||
58 | /** | |
59 | * ubi_get_volume_info - get information about UBI volume. | |
60 | * @desc: volume descriptor | |
61 | * @vi: the information is stored here | |
62 | */ | |
63 | void ubi_get_volume_info(struct ubi_volume_desc *desc, | |
64 | struct ubi_volume_info *vi) | |
65 | { | |
66 | const struct ubi_volume *vol = desc->vol; | |
67 | const struct ubi_device *ubi = vol->ubi; | |
68 | ||
69 | vi->vol_id = vol->vol_id; | |
70 | vi->ubi_num = ubi->ubi_num; | |
71 | vi->size = vol->reserved_pebs; | |
72 | vi->used_bytes = vol->used_bytes; | |
73 | vi->vol_type = vol->vol_type; | |
74 | vi->corrupted = vol->corrupted; | |
75 | vi->upd_marker = vol->upd_marker; | |
76 | vi->alignment = vol->alignment; | |
77 | vi->usable_leb_size = vol->usable_leb_size; | |
78 | vi->name_len = vol->name_len; | |
79 | vi->name = vol->name; | |
49dfc299 | 80 | vi->cdev = vol->cdev.dev; |
801c135c AB |
81 | } |
82 | EXPORT_SYMBOL_GPL(ubi_get_volume_info); | |
83 | ||
84 | /** | |
85 | * ubi_open_volume - open UBI volume. | |
86 | * @ubi_num: UBI device number | |
87 | * @vol_id: volume ID | |
88 | * @mode: open mode | |
89 | * | |
90 | * The @mode parameter specifies if the volume should be opened in read-only | |
91 | * mode, read-write mode, or exclusive mode. The exclusive mode guarantees that | |
92 | * nobody else will be able to open this volume. UBI allows to have many volume | |
93 | * readers and one writer at a time. | |
94 | * | |
95 | * If a static volume is being opened for the first time since boot, it will be | |
96 | * checked by this function, which means it will be fully read and the CRC | |
97 | * checksum of each logical eraseblock will be checked. | |
98 | * | |
99 | * This function returns volume descriptor in case of success and a negative | |
100 | * error code in case of failure. | |
101 | */ | |
102 | struct ubi_volume_desc *ubi_open_volume(int ubi_num, int vol_id, int mode) | |
103 | { | |
104 | int err; | |
105 | struct ubi_volume_desc *desc; | |
0169b49d | 106 | struct ubi_device *ubi; |
801c135c AB |
107 | struct ubi_volume *vol; |
108 | ||
109 | dbg_msg("open device %d volume %d, mode %d", ubi_num, vol_id, mode); | |
110 | ||
35ad5fb7 AB |
111 | if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES) |
112 | return ERR_PTR(-EINVAL); | |
0169b49d | 113 | |
35ad5fb7 AB |
114 | if (mode != UBI_READONLY && mode != UBI_READWRITE && |
115 | mode != UBI_EXCLUSIVE) | |
116 | return ERR_PTR(-EINVAL); | |
801c135c | 117 | |
e73f4459 AB |
118 | /* |
119 | * First of all, we have to get the UBI device to prevent its removal. | |
120 | */ | |
121 | ubi = ubi_get_device(ubi_num); | |
35ad5fb7 AB |
122 | if (!ubi) |
123 | return ERR_PTR(-ENODEV); | |
801c135c | 124 | |
e73f4459 AB |
125 | if (vol_id < 0 || vol_id >= ubi->vtbl_slots) { |
126 | err = -EINVAL; | |
127 | goto out_put_ubi; | |
128 | } | |
801c135c AB |
129 | |
130 | desc = kmalloc(sizeof(struct ubi_volume_desc), GFP_KERNEL); | |
e73f4459 AB |
131 | if (!desc) { |
132 | err = -ENOMEM; | |
133 | goto out_put_ubi; | |
134 | } | |
35ad5fb7 AB |
135 | |
136 | err = -ENODEV; | |
137 | if (!try_module_get(THIS_MODULE)) | |
138 | goto out_free; | |
801c135c AB |
139 | |
140 | spin_lock(&ubi->volumes_lock); | |
141 | vol = ubi->volumes[vol_id]; | |
35ad5fb7 | 142 | if (!vol) |
801c135c | 143 | goto out_unlock; |
801c135c AB |
144 | |
145 | err = -EBUSY; | |
146 | switch (mode) { | |
147 | case UBI_READONLY: | |
148 | if (vol->exclusive) | |
149 | goto out_unlock; | |
150 | vol->readers += 1; | |
151 | break; | |
152 | ||
153 | case UBI_READWRITE: | |
154 | if (vol->exclusive || vol->writers > 0) | |
155 | goto out_unlock; | |
156 | vol->writers += 1; | |
157 | break; | |
158 | ||
159 | case UBI_EXCLUSIVE: | |
160 | if (vol->exclusive || vol->writers || vol->readers) | |
161 | goto out_unlock; | |
162 | vol->exclusive = 1; | |
163 | break; | |
164 | } | |
450f872a | 165 | get_device(&vol->dev); |
d05c77a8 | 166 | vol->ref_count += 1; |
801c135c AB |
167 | spin_unlock(&ubi->volumes_lock); |
168 | ||
169 | desc->vol = vol; | |
170 | desc->mode = mode; | |
171 | ||
783b273a | 172 | mutex_lock(&ubi->ckvol_mutex); |
801c135c AB |
173 | if (!vol->checked) { |
174 | /* This is the first open - check the volume */ | |
175 | err = ubi_check_volume(ubi, vol_id); | |
176 | if (err < 0) { | |
783b273a | 177 | mutex_unlock(&ubi->ckvol_mutex); |
801c135c AB |
178 | ubi_close_volume(desc); |
179 | return ERR_PTR(err); | |
180 | } | |
181 | if (err == 1) { | |
182 | ubi_warn("volume %d on UBI device %d is corrupted", | |
183 | vol_id, ubi->ubi_num); | |
184 | vol->corrupted = 1; | |
185 | } | |
186 | vol->checked = 1; | |
187 | } | |
783b273a | 188 | mutex_unlock(&ubi->ckvol_mutex); |
35ad5fb7 | 189 | |
801c135c AB |
190 | return desc; |
191 | ||
192 | out_unlock: | |
193 | spin_unlock(&ubi->volumes_lock); | |
801c135c | 194 | module_put(THIS_MODULE); |
35ad5fb7 AB |
195 | out_free: |
196 | kfree(desc); | |
e73f4459 AB |
197 | out_put_ubi: |
198 | ubi_put_device(ubi); | |
801c135c AB |
199 | return ERR_PTR(err); |
200 | } | |
201 | EXPORT_SYMBOL_GPL(ubi_open_volume); | |
202 | ||
203 | /** | |
204 | * ubi_open_volume_nm - open UBI volume by name. | |
205 | * @ubi_num: UBI device number | |
206 | * @name: volume name | |
207 | * @mode: open mode | |
208 | * | |
209 | * This function is similar to 'ubi_open_volume()', but opens a volume by name. | |
210 | */ | |
211 | struct ubi_volume_desc *ubi_open_volume_nm(int ubi_num, const char *name, | |
212 | int mode) | |
213 | { | |
214 | int i, vol_id = -1, len; | |
801c135c | 215 | struct ubi_device *ubi; |
e73f4459 | 216 | struct ubi_volume_desc *ret; |
801c135c AB |
217 | |
218 | dbg_msg("open volume %s, mode %d", name, mode); | |
219 | ||
220 | if (!name) | |
221 | return ERR_PTR(-EINVAL); | |
222 | ||
223 | len = strnlen(name, UBI_VOL_NAME_MAX + 1); | |
224 | if (len > UBI_VOL_NAME_MAX) | |
225 | return ERR_PTR(-EINVAL); | |
226 | ||
35ad5fb7 AB |
227 | if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES) |
228 | return ERR_PTR(-EINVAL); | |
801c135c | 229 | |
e73f4459 | 230 | ubi = ubi_get_device(ubi_num); |
35ad5fb7 AB |
231 | if (!ubi) |
232 | return ERR_PTR(-ENODEV); | |
801c135c AB |
233 | |
234 | spin_lock(&ubi->volumes_lock); | |
235 | /* Walk all volumes of this UBI device */ | |
236 | for (i = 0; i < ubi->vtbl_slots; i++) { | |
237 | struct ubi_volume *vol = ubi->volumes[i]; | |
238 | ||
239 | if (vol && len == vol->name_len && !strcmp(name, vol->name)) { | |
240 | vol_id = i; | |
241 | break; | |
242 | } | |
243 | } | |
244 | spin_unlock(&ubi->volumes_lock); | |
245 | ||
e73f4459 AB |
246 | if (vol_id >= 0) |
247 | ret = ubi_open_volume(ubi_num, vol_id, mode); | |
248 | else | |
249 | ret = ERR_PTR(-ENODEV); | |
801c135c | 250 | |
e73f4459 AB |
251 | /* |
252 | * We should put the UBI device even in case of success, because | |
253 | * 'ubi_open_volume()' took a reference as well. | |
254 | */ | |
255 | ubi_put_device(ubi); | |
256 | return ret; | |
801c135c AB |
257 | } |
258 | EXPORT_SYMBOL_GPL(ubi_open_volume_nm); | |
259 | ||
260 | /** | |
261 | * ubi_close_volume - close UBI volume. | |
262 | * @desc: volume descriptor | |
263 | */ | |
264 | void ubi_close_volume(struct ubi_volume_desc *desc) | |
265 | { | |
266 | struct ubi_volume *vol = desc->vol; | |
e73f4459 | 267 | struct ubi_device *ubi = vol->ubi; |
801c135c AB |
268 | |
269 | dbg_msg("close volume %d, mode %d", vol->vol_id, desc->mode); | |
270 | ||
e73f4459 | 271 | spin_lock(&ubi->volumes_lock); |
801c135c AB |
272 | switch (desc->mode) { |
273 | case UBI_READONLY: | |
274 | vol->readers -= 1; | |
275 | break; | |
276 | case UBI_READWRITE: | |
277 | vol->writers -= 1; | |
278 | break; | |
279 | case UBI_EXCLUSIVE: | |
280 | vol->exclusive = 0; | |
281 | } | |
d05c77a8 | 282 | vol->ref_count -= 1; |
e73f4459 | 283 | spin_unlock(&ubi->volumes_lock); |
801c135c | 284 | |
d05c77a8 | 285 | kfree(desc); |
e73f4459 AB |
286 | put_device(&vol->dev); |
287 | ubi_put_device(ubi); | |
801c135c AB |
288 | module_put(THIS_MODULE); |
289 | } | |
290 | EXPORT_SYMBOL_GPL(ubi_close_volume); | |
291 | ||
292 | /** | |
293 | * ubi_leb_read - read data. | |
294 | * @desc: volume descriptor | |
295 | * @lnum: logical eraseblock number to read from | |
296 | * @buf: buffer where to store the read data | |
297 | * @offset: offset within the logical eraseblock to read from | |
298 | * @len: how many bytes to read | |
299 | * @check: whether UBI has to check the read data's CRC or not. | |
300 | * | |
301 | * This function reads data from offset @offset of logical eraseblock @lnum and | |
302 | * stores the data at @buf. When reading from static volumes, @check specifies | |
303 | * whether the data has to be checked or not. If yes, the whole logical | |
304 | * eraseblock will be read and its CRC checksum will be checked (i.e., the CRC | |
305 | * checksum is per-eraseblock). So checking may substantially slow down the | |
306 | * read speed. The @check argument is ignored for dynamic volumes. | |
307 | * | |
308 | * In case of success, this function returns zero. In case of failure, this | |
309 | * function returns a negative error code. | |
310 | * | |
311 | * %-EBADMSG error code is returned: | |
312 | * o for both static and dynamic volumes if MTD driver has detected a data | |
313 | * integrity problem (unrecoverable ECC checksum mismatch in case of NAND); | |
314 | * o for static volumes in case of data CRC mismatch. | |
315 | * | |
316 | * If the volume is damaged because of an interrupted update this function just | |
317 | * returns immediately with %-EBADF error code. | |
318 | */ | |
319 | int ubi_leb_read(struct ubi_volume_desc *desc, int lnum, char *buf, int offset, | |
320 | int len, int check) | |
321 | { | |
322 | struct ubi_volume *vol = desc->vol; | |
323 | struct ubi_device *ubi = vol->ubi; | |
324 | int err, vol_id = vol->vol_id; | |
325 | ||
326 | dbg_msg("read %d bytes from LEB %d:%d:%d", len, vol_id, lnum, offset); | |
327 | ||
328 | if (vol_id < 0 || vol_id >= ubi->vtbl_slots || lnum < 0 || | |
329 | lnum >= vol->used_ebs || offset < 0 || len < 0 || | |
330 | offset + len > vol->usable_leb_size) | |
331 | return -EINVAL; | |
332 | ||
4ab60a0d AB |
333 | if (vol->vol_type == UBI_STATIC_VOLUME) { |
334 | if (vol->used_ebs == 0) | |
335 | /* Empty static UBI volume */ | |
336 | return 0; | |
337 | if (lnum == vol->used_ebs - 1 && | |
338 | offset + len > vol->last_eb_bytes) | |
339 | return -EINVAL; | |
340 | } | |
801c135c AB |
341 | |
342 | if (vol->upd_marker) | |
343 | return -EBADF; | |
344 | if (len == 0) | |
345 | return 0; | |
346 | ||
89b96b69 | 347 | err = ubi_eba_read_leb(ubi, vol, lnum, buf, offset, len, check); |
801c135c AB |
348 | if (err && err == -EBADMSG && vol->vol_type == UBI_STATIC_VOLUME) { |
349 | ubi_warn("mark volume %d as corrupted", vol_id); | |
350 | vol->corrupted = 1; | |
351 | } | |
352 | ||
353 | return err; | |
354 | } | |
355 | EXPORT_SYMBOL_GPL(ubi_leb_read); | |
356 | ||
357 | /** | |
358 | * ubi_leb_write - write data. | |
359 | * @desc: volume descriptor | |
360 | * @lnum: logical eraseblock number to write to | |
361 | * @buf: data to write | |
362 | * @offset: offset within the logical eraseblock where to write | |
363 | * @len: how many bytes to write | |
364 | * @dtype: expected data type | |
365 | * | |
366 | * This function writes @len bytes of data from @buf to offset @offset of | |
367 | * logical eraseblock @lnum. The @dtype argument describes expected lifetime of | |
368 | * the data. | |
369 | * | |
370 | * This function takes care of physical eraseblock write failures. If write to | |
371 | * the physical eraseblock write operation fails, the logical eraseblock is | |
372 | * re-mapped to another physical eraseblock, the data is recovered, and the | |
373 | * write finishes. UBI has a pool of reserved physical eraseblocks for this. | |
374 | * | |
375 | * If all the data were successfully written, zero is returned. If an error | |
376 | * occurred and UBI has not been able to recover from it, this function returns | |
377 | * a negative error code. Note, in case of an error, it is possible that | |
378 | * something was still written to the flash media, but that may be some | |
379 | * garbage. | |
380 | * | |
381 | * If the volume is damaged because of an interrupted update this function just | |
382 | * returns immediately with %-EBADF code. | |
383 | */ | |
384 | int ubi_leb_write(struct ubi_volume_desc *desc, int lnum, const void *buf, | |
385 | int offset, int len, int dtype) | |
386 | { | |
387 | struct ubi_volume *vol = desc->vol; | |
388 | struct ubi_device *ubi = vol->ubi; | |
389 | int vol_id = vol->vol_id; | |
390 | ||
391 | dbg_msg("write %d bytes to LEB %d:%d:%d", len, vol_id, lnum, offset); | |
392 | ||
393 | if (vol_id < 0 || vol_id >= ubi->vtbl_slots) | |
394 | return -EINVAL; | |
395 | ||
396 | if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME) | |
397 | return -EROFS; | |
398 | ||
399 | if (lnum < 0 || lnum >= vol->reserved_pebs || offset < 0 || len < 0 || | |
400 | offset + len > vol->usable_leb_size || offset % ubi->min_io_size || | |
401 | len % ubi->min_io_size) | |
402 | return -EINVAL; | |
403 | ||
404 | if (dtype != UBI_LONGTERM && dtype != UBI_SHORTTERM && | |
405 | dtype != UBI_UNKNOWN) | |
406 | return -EINVAL; | |
407 | ||
408 | if (vol->upd_marker) | |
409 | return -EBADF; | |
410 | ||
411 | if (len == 0) | |
412 | return 0; | |
413 | ||
89b96b69 | 414 | return ubi_eba_write_leb(ubi, vol, lnum, buf, offset, len, dtype); |
801c135c AB |
415 | } |
416 | EXPORT_SYMBOL_GPL(ubi_leb_write); | |
417 | ||
418 | /* | |
419 | * ubi_leb_change - change logical eraseblock atomically. | |
420 | * @desc: volume descriptor | |
421 | * @lnum: logical eraseblock number to change | |
422 | * @buf: data to write | |
423 | * @len: how many bytes to write | |
424 | * @dtype: expected data type | |
425 | * | |
426 | * This function changes the contents of a logical eraseblock atomically. @buf | |
427 | * has to contain new logical eraseblock data, and @len - the length of the | |
428 | * data, which has to be aligned. The length may be shorter then the logical | |
429 | * eraseblock size, ant the logical eraseblock may be appended to more times | |
430 | * later on. This function guarantees that in case of an unclean reboot the old | |
431 | * contents is preserved. Returns zero in case of success and a negative error | |
432 | * code in case of failure. | |
433 | */ | |
434 | int ubi_leb_change(struct ubi_volume_desc *desc, int lnum, const void *buf, | |
435 | int len, int dtype) | |
436 | { | |
437 | struct ubi_volume *vol = desc->vol; | |
438 | struct ubi_device *ubi = vol->ubi; | |
439 | int vol_id = vol->vol_id; | |
440 | ||
441 | dbg_msg("atomically write %d bytes to LEB %d:%d", len, vol_id, lnum); | |
442 | ||
443 | if (vol_id < 0 || vol_id >= ubi->vtbl_slots) | |
444 | return -EINVAL; | |
445 | ||
446 | if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME) | |
447 | return -EROFS; | |
448 | ||
449 | if (lnum < 0 || lnum >= vol->reserved_pebs || len < 0 || | |
450 | len > vol->usable_leb_size || len % ubi->min_io_size) | |
451 | return -EINVAL; | |
452 | ||
453 | if (dtype != UBI_LONGTERM && dtype != UBI_SHORTTERM && | |
454 | dtype != UBI_UNKNOWN) | |
455 | return -EINVAL; | |
456 | ||
457 | if (vol->upd_marker) | |
458 | return -EBADF; | |
459 | ||
460 | if (len == 0) | |
461 | return 0; | |
462 | ||
89b96b69 | 463 | return ubi_eba_atomic_leb_change(ubi, vol, lnum, buf, len, dtype); |
801c135c AB |
464 | } |
465 | EXPORT_SYMBOL_GPL(ubi_leb_change); | |
466 | ||
467 | /** | |
468 | * ubi_leb_erase - erase logical eraseblock. | |
469 | * @desc: volume descriptor | |
470 | * @lnum: logical eraseblock number | |
471 | * | |
472 | * This function un-maps logical eraseblock @lnum and synchronously erases the | |
473 | * correspondent physical eraseblock. Returns zero in case of success and a | |
474 | * negative error code in case of failure. | |
475 | * | |
476 | * If the volume is damaged because of an interrupted update this function just | |
477 | * returns immediately with %-EBADF code. | |
478 | */ | |
479 | int ubi_leb_erase(struct ubi_volume_desc *desc, int lnum) | |
480 | { | |
481 | struct ubi_volume *vol = desc->vol; | |
482 | struct ubi_device *ubi = vol->ubi; | |
ae616e1b | 483 | int err; |
801c135c | 484 | |
ae616e1b | 485 | dbg_msg("erase LEB %d:%d", vol->vol_id, lnum); |
801c135c AB |
486 | |
487 | if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME) | |
488 | return -EROFS; | |
489 | ||
490 | if (lnum < 0 || lnum >= vol->reserved_pebs) | |
491 | return -EINVAL; | |
492 | ||
493 | if (vol->upd_marker) | |
494 | return -EBADF; | |
495 | ||
89b96b69 | 496 | err = ubi_eba_unmap_leb(ubi, vol, lnum); |
801c135c AB |
497 | if (err) |
498 | return err; | |
499 | ||
500 | return ubi_wl_flush(ubi); | |
501 | } | |
502 | EXPORT_SYMBOL_GPL(ubi_leb_erase); | |
503 | ||
504 | /** | |
505 | * ubi_leb_unmap - un-map logical eraseblock. | |
506 | * @desc: volume descriptor | |
507 | * @lnum: logical eraseblock number | |
508 | * | |
509 | * This function un-maps logical eraseblock @lnum and schedules the | |
510 | * corresponding physical eraseblock for erasure, so that it will eventually be | |
511 | * physically erased in background. This operation is much faster then the | |
512 | * erase operation. | |
513 | * | |
514 | * Unlike erase, the un-map operation does not guarantee that the logical | |
515 | * eraseblock will contain all 0xFF bytes when UBI is initialized again. For | |
516 | * example, if several logical eraseblocks are un-mapped, and an unclean reboot | |
517 | * happens after this, the logical eraseblocks will not necessarily be | |
518 | * un-mapped again when this MTD device is attached. They may actually be | |
519 | * mapped to the same physical eraseblocks again. So, this function has to be | |
520 | * used with care. | |
521 | * | |
522 | * In other words, when un-mapping a logical eraseblock, UBI does not store | |
523 | * any information about this on the flash media, it just marks the logical | |
524 | * eraseblock as "un-mapped" in RAM. If UBI is detached before the physical | |
525 | * eraseblock is physically erased, it will be mapped again to the same logical | |
526 | * eraseblock when the MTD device is attached again. | |
527 | * | |
528 | * The main and obvious use-case of this function is when the contents of a | |
529 | * logical eraseblock has to be re-written. Then it is much more efficient to | |
530 | * first un-map it, then write new data, rather then first erase it, then write | |
531 | * new data. Note, once new data has been written to the logical eraseblock, | |
532 | * UBI guarantees that the old contents has gone forever. In other words, if an | |
533 | * unclean reboot happens after the logical eraseblock has been un-mapped and | |
534 | * then written to, it will contain the last written data. | |
535 | * | |
536 | * This function returns zero in case of success and a negative error code in | |
537 | * case of failure. If the volume is damaged because of an interrupted update | |
538 | * this function just returns immediately with %-EBADF code. | |
539 | */ | |
540 | int ubi_leb_unmap(struct ubi_volume_desc *desc, int lnum) | |
541 | { | |
542 | struct ubi_volume *vol = desc->vol; | |
543 | struct ubi_device *ubi = vol->ubi; | |
801c135c | 544 | |
ae616e1b | 545 | dbg_msg("unmap LEB %d:%d", vol->vol_id, lnum); |
801c135c AB |
546 | |
547 | if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME) | |
548 | return -EROFS; | |
549 | ||
550 | if (lnum < 0 || lnum >= vol->reserved_pebs) | |
551 | return -EINVAL; | |
552 | ||
553 | if (vol->upd_marker) | |
554 | return -EBADF; | |
555 | ||
89b96b69 | 556 | return ubi_eba_unmap_leb(ubi, vol, lnum); |
801c135c AB |
557 | } |
558 | EXPORT_SYMBOL_GPL(ubi_leb_unmap); | |
393852ec AB |
559 | |
560 | /** | |
561 | * ubi_leb_map - map logical erasblock to a physical eraseblock. | |
562 | * @desc: volume descriptor | |
563 | * @lnum: logical eraseblock number | |
564 | * @dtype: expected data type | |
565 | * | |
566 | * This function maps an un-mapped logical eraseblock @lnum to a physical | |
567 | * eraseblock. This means, that after a successfull invocation of this | |
568 | * function the logical eraseblock @lnum will be empty (contain only %0xFF | |
569 | * bytes) and be mapped to a physical eraseblock, even if an unclean reboot | |
570 | * happens. | |
571 | * | |
572 | * This function returns zero in case of success, %-EBADF if the volume is | |
573 | * damaged because of an interrupted update, %-EBADMSG if the logical | |
574 | * eraseblock is already mapped, and other negative error codes in case of | |
575 | * other failures. | |
576 | */ | |
577 | int ubi_leb_map(struct ubi_volume_desc *desc, int lnum, int dtype) | |
578 | { | |
579 | struct ubi_volume *vol = desc->vol; | |
580 | struct ubi_device *ubi = vol->ubi; | |
393852ec | 581 | |
ae616e1b | 582 | dbg_msg("unmap LEB %d:%d", vol->vol_id, lnum); |
393852ec AB |
583 | |
584 | if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME) | |
585 | return -EROFS; | |
586 | ||
587 | if (lnum < 0 || lnum >= vol->reserved_pebs) | |
588 | return -EINVAL; | |
589 | ||
590 | if (dtype != UBI_LONGTERM && dtype != UBI_SHORTTERM && | |
591 | dtype != UBI_UNKNOWN) | |
592 | return -EINVAL; | |
593 | ||
594 | if (vol->upd_marker) | |
595 | return -EBADF; | |
596 | ||
597 | if (vol->eba_tbl[lnum] >= 0) | |
598 | return -EBADMSG; | |
599 | ||
89b96b69 | 600 | return ubi_eba_write_leb(ubi, vol, lnum, NULL, 0, 0, dtype); |
393852ec AB |
601 | } |
602 | EXPORT_SYMBOL_GPL(ubi_leb_map); | |
801c135c AB |
603 | |
604 | /** | |
605 | * ubi_is_mapped - check if logical eraseblock is mapped. | |
606 | * @desc: volume descriptor | |
607 | * @lnum: logical eraseblock number | |
608 | * | |
609 | * This function checks if logical eraseblock @lnum is mapped to a physical | |
610 | * eraseblock. If a logical eraseblock is un-mapped, this does not necessarily | |
611 | * mean it will still be un-mapped after the UBI device is re-attached. The | |
612 | * logical eraseblock may become mapped to the physical eraseblock it was last | |
613 | * mapped to. | |
614 | * | |
615 | * This function returns %1 if the LEB is mapped, %0 if not, and a negative | |
616 | * error code in case of failure. If the volume is damaged because of an | |
617 | * interrupted update this function just returns immediately with %-EBADF error | |
618 | * code. | |
619 | */ | |
620 | int ubi_is_mapped(struct ubi_volume_desc *desc, int lnum) | |
621 | { | |
622 | struct ubi_volume *vol = desc->vol; | |
623 | ||
624 | dbg_msg("test LEB %d:%d", vol->vol_id, lnum); | |
625 | ||
626 | if (lnum < 0 || lnum >= vol->reserved_pebs) | |
627 | return -EINVAL; | |
628 | ||
629 | if (vol->upd_marker) | |
630 | return -EBADF; | |
631 | ||
632 | return vol->eba_tbl[lnum] >= 0; | |
633 | } | |
634 | EXPORT_SYMBOL_GPL(ubi_is_mapped); |