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1a59d1b8 | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
801c135c AB |
2 | /* |
3 | * Copyright (c) International Business Machines Corp., 2006 | |
4 | * | |
801c135c AB |
5 | * Author: Artem Bityutskiy (Битюцкий Артём) |
6 | */ | |
7 | ||
8 | /* This file mostly implements UBI kernel API functions */ | |
9 | ||
10 | #include <linux/module.h> | |
11 | #include <linux/err.h> | |
5a0e3ad6 | 12 | #include <linux/slab.h> |
b5710284 CC |
13 | #include <linux/namei.h> |
14 | #include <linux/fs.h> | |
801c135c AB |
15 | #include <asm/div64.h> |
16 | #include "ubi.h" | |
17 | ||
0e0ee1cc DP |
18 | /** |
19 | * ubi_do_get_device_info - get information about UBI device. | |
20 | * @ubi: UBI device description object | |
21 | * @di: the information is stored here | |
22 | * | |
23 | * This function is the same as 'ubi_get_device_info()', but it assumes the UBI | |
24 | * device is locked and cannot disappear. | |
25 | */ | |
26 | void ubi_do_get_device_info(struct ubi_device *ubi, struct ubi_device_info *di) | |
27 | { | |
28 | di->ubi_num = ubi->ubi_num; | |
29 | di->leb_size = ubi->leb_size; | |
f43ec882 | 30 | di->leb_start = ubi->leb_start; |
0e0ee1cc | 31 | di->min_io_size = ubi->min_io_size; |
30b542ef | 32 | di->max_write_size = ubi->max_write_size; |
0e0ee1cc DP |
33 | di->ro_mode = ubi->ro_mode; |
34 | di->cdev = ubi->cdev.dev; | |
35 | } | |
36 | EXPORT_SYMBOL_GPL(ubi_do_get_device_info); | |
37 | ||
801c135c AB |
38 | /** |
39 | * ubi_get_device_info - get information about UBI device. | |
40 | * @ubi_num: UBI device number | |
41 | * @di: the information is stored here | |
42 | * | |
e73f4459 AB |
43 | * This function returns %0 in case of success, %-EINVAL if the UBI device |
44 | * number is invalid, and %-ENODEV if there is no such UBI device. | |
801c135c AB |
45 | */ |
46 | int ubi_get_device_info(int ubi_num, struct ubi_device_info *di) | |
47 | { | |
e73f4459 AB |
48 | struct ubi_device *ubi; |
49 | ||
50 | if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES) | |
51 | return -EINVAL; | |
e73f4459 AB |
52 | ubi = ubi_get_device(ubi_num); |
53 | if (!ubi) | |
801c135c | 54 | return -ENODEV; |
0e0ee1cc | 55 | ubi_do_get_device_info(ubi, di); |
e73f4459 | 56 | ubi_put_device(ubi); |
801c135c AB |
57 | return 0; |
58 | } | |
59 | EXPORT_SYMBOL_GPL(ubi_get_device_info); | |
60 | ||
61 | /** | |
0e0ee1cc DP |
62 | * ubi_do_get_volume_info - get information about UBI volume. |
63 | * @ubi: UBI device description object | |
64 | * @vol: volume description object | |
801c135c AB |
65 | * @vi: the information is stored here |
66 | */ | |
0e0ee1cc DP |
67 | void ubi_do_get_volume_info(struct ubi_device *ubi, struct ubi_volume *vol, |
68 | struct ubi_volume_info *vi) | |
801c135c | 69 | { |
801c135c AB |
70 | vi->vol_id = vol->vol_id; |
71 | vi->ubi_num = ubi->ubi_num; | |
72 | vi->size = vol->reserved_pebs; | |
73 | vi->used_bytes = vol->used_bytes; | |
74 | vi->vol_type = vol->vol_type; | |
75 | vi->corrupted = vol->corrupted; | |
76 | vi->upd_marker = vol->upd_marker; | |
77 | vi->alignment = vol->alignment; | |
78 | vi->usable_leb_size = vol->usable_leb_size; | |
79 | vi->name_len = vol->name_len; | |
80 | vi->name = vol->name; | |
49dfc299 | 81 | vi->cdev = vol->cdev.dev; |
05b8773c | 82 | vi->dev = &vol->dev; |
801c135c | 83 | } |
0e0ee1cc DP |
84 | |
85 | /** | |
86 | * ubi_get_volume_info - get information about UBI volume. | |
87 | * @desc: volume descriptor | |
88 | * @vi: the information is stored here | |
89 | */ | |
90 | void ubi_get_volume_info(struct ubi_volume_desc *desc, | |
91 | struct ubi_volume_info *vi) | |
92 | { | |
93 | ubi_do_get_volume_info(desc->vol->ubi, desc->vol, vi); | |
94 | } | |
801c135c AB |
95 | EXPORT_SYMBOL_GPL(ubi_get_volume_info); |
96 | ||
97 | /** | |
98 | * ubi_open_volume - open UBI volume. | |
99 | * @ubi_num: UBI device number | |
100 | * @vol_id: volume ID | |
101 | * @mode: open mode | |
102 | * | |
103 | * The @mode parameter specifies if the volume should be opened in read-only | |
104 | * mode, read-write mode, or exclusive mode. The exclusive mode guarantees that | |
105 | * nobody else will be able to open this volume. UBI allows to have many volume | |
106 | * readers and one writer at a time. | |
107 | * | |
108 | * If a static volume is being opened for the first time since boot, it will be | |
109 | * checked by this function, which means it will be fully read and the CRC | |
110 | * checksum of each logical eraseblock will be checked. | |
111 | * | |
112 | * This function returns volume descriptor in case of success and a negative | |
113 | * error code in case of failure. | |
114 | */ | |
115 | struct ubi_volume_desc *ubi_open_volume(int ubi_num, int vol_id, int mode) | |
116 | { | |
117 | int err; | |
118 | struct ubi_volume_desc *desc; | |
0169b49d | 119 | struct ubi_device *ubi; |
801c135c AB |
120 | struct ubi_volume *vol; |
121 | ||
e1cf7e6d | 122 | dbg_gen("open device %d, volume %d, mode %d", ubi_num, vol_id, mode); |
801c135c | 123 | |
35ad5fb7 AB |
124 | if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES) |
125 | return ERR_PTR(-EINVAL); | |
0169b49d | 126 | |
35ad5fb7 | 127 | if (mode != UBI_READONLY && mode != UBI_READWRITE && |
fafdd2bf | 128 | mode != UBI_EXCLUSIVE && mode != UBI_METAONLY) |
35ad5fb7 | 129 | return ERR_PTR(-EINVAL); |
801c135c | 130 | |
e73f4459 AB |
131 | /* |
132 | * First of all, we have to get the UBI device to prevent its removal. | |
133 | */ | |
134 | ubi = ubi_get_device(ubi_num); | |
35ad5fb7 AB |
135 | if (!ubi) |
136 | return ERR_PTR(-ENODEV); | |
801c135c | 137 | |
e73f4459 AB |
138 | if (vol_id < 0 || vol_id >= ubi->vtbl_slots) { |
139 | err = -EINVAL; | |
140 | goto out_put_ubi; | |
141 | } | |
801c135c AB |
142 | |
143 | desc = kmalloc(sizeof(struct ubi_volume_desc), GFP_KERNEL); | |
e73f4459 AB |
144 | if (!desc) { |
145 | err = -ENOMEM; | |
146 | goto out_put_ubi; | |
147 | } | |
35ad5fb7 AB |
148 | |
149 | err = -ENODEV; | |
150 | if (!try_module_get(THIS_MODULE)) | |
151 | goto out_free; | |
801c135c AB |
152 | |
153 | spin_lock(&ubi->volumes_lock); | |
154 | vol = ubi->volumes[vol_id]; | |
7e84c961 | 155 | if (!vol || vol->is_dead) |
801c135c | 156 | goto out_unlock; |
801c135c AB |
157 | |
158 | err = -EBUSY; | |
159 | switch (mode) { | |
160 | case UBI_READONLY: | |
161 | if (vol->exclusive) | |
162 | goto out_unlock; | |
163 | vol->readers += 1; | |
164 | break; | |
165 | ||
166 | case UBI_READWRITE: | |
167 | if (vol->exclusive || vol->writers > 0) | |
168 | goto out_unlock; | |
169 | vol->writers += 1; | |
170 | break; | |
171 | ||
172 | case UBI_EXCLUSIVE: | |
fafdd2bf RW |
173 | if (vol->exclusive || vol->writers || vol->readers || |
174 | vol->metaonly) | |
801c135c AB |
175 | goto out_unlock; |
176 | vol->exclusive = 1; | |
177 | break; | |
fafdd2bf RW |
178 | |
179 | case UBI_METAONLY: | |
180 | if (vol->metaonly || vol->exclusive) | |
181 | goto out_unlock; | |
182 | vol->metaonly = 1; | |
183 | break; | |
801c135c | 184 | } |
450f872a | 185 | get_device(&vol->dev); |
d05c77a8 | 186 | vol->ref_count += 1; |
801c135c AB |
187 | spin_unlock(&ubi->volumes_lock); |
188 | ||
189 | desc->vol = vol; | |
190 | desc->mode = mode; | |
191 | ||
783b273a | 192 | mutex_lock(&ubi->ckvol_mutex); |
62652517 | 193 | if (!vol->checked && !vol->skip_check) { |
801c135c AB |
194 | /* This is the first open - check the volume */ |
195 | err = ubi_check_volume(ubi, vol_id); | |
196 | if (err < 0) { | |
783b273a | 197 | mutex_unlock(&ubi->ckvol_mutex); |
801c135c AB |
198 | ubi_close_volume(desc); |
199 | return ERR_PTR(err); | |
200 | } | |
201 | if (err == 1) { | |
32608703 | 202 | ubi_warn(ubi, "volume %d on UBI device %d is corrupted", |
801c135c AB |
203 | vol_id, ubi->ubi_num); |
204 | vol->corrupted = 1; | |
205 | } | |
206 | vol->checked = 1; | |
207 | } | |
783b273a | 208 | mutex_unlock(&ubi->ckvol_mutex); |
35ad5fb7 | 209 | |
801c135c AB |
210 | return desc; |
211 | ||
212 | out_unlock: | |
213 | spin_unlock(&ubi->volumes_lock); | |
801c135c | 214 | module_put(THIS_MODULE); |
35ad5fb7 AB |
215 | out_free: |
216 | kfree(desc); | |
e73f4459 | 217 | out_put_ubi: |
32608703 | 218 | ubi_err(ubi, "cannot open device %d, volume %d, error %d", |
e1cf7e6d | 219 | ubi_num, vol_id, err); |
e5420877 | 220 | ubi_put_device(ubi); |
801c135c AB |
221 | return ERR_PTR(err); |
222 | } | |
223 | EXPORT_SYMBOL_GPL(ubi_open_volume); | |
224 | ||
225 | /** | |
226 | * ubi_open_volume_nm - open UBI volume by name. | |
227 | * @ubi_num: UBI device number | |
228 | * @name: volume name | |
229 | * @mode: open mode | |
230 | * | |
231 | * This function is similar to 'ubi_open_volume()', but opens a volume by name. | |
232 | */ | |
233 | struct ubi_volume_desc *ubi_open_volume_nm(int ubi_num, const char *name, | |
234 | int mode) | |
235 | { | |
236 | int i, vol_id = -1, len; | |
801c135c | 237 | struct ubi_device *ubi; |
e73f4459 | 238 | struct ubi_volume_desc *ret; |
801c135c | 239 | |
e1cf7e6d | 240 | dbg_gen("open device %d, volume %s, mode %d", ubi_num, name, mode); |
801c135c AB |
241 | |
242 | if (!name) | |
243 | return ERR_PTR(-EINVAL); | |
244 | ||
245 | len = strnlen(name, UBI_VOL_NAME_MAX + 1); | |
246 | if (len > UBI_VOL_NAME_MAX) | |
247 | return ERR_PTR(-EINVAL); | |
248 | ||
35ad5fb7 AB |
249 | if (ubi_num < 0 || ubi_num >= UBI_MAX_DEVICES) |
250 | return ERR_PTR(-EINVAL); | |
801c135c | 251 | |
e73f4459 | 252 | ubi = ubi_get_device(ubi_num); |
35ad5fb7 AB |
253 | if (!ubi) |
254 | return ERR_PTR(-ENODEV); | |
801c135c AB |
255 | |
256 | spin_lock(&ubi->volumes_lock); | |
257 | /* Walk all volumes of this UBI device */ | |
258 | for (i = 0; i < ubi->vtbl_slots; i++) { | |
259 | struct ubi_volume *vol = ubi->volumes[i]; | |
260 | ||
261 | if (vol && len == vol->name_len && !strcmp(name, vol->name)) { | |
262 | vol_id = i; | |
263 | break; | |
264 | } | |
265 | } | |
266 | spin_unlock(&ubi->volumes_lock); | |
267 | ||
e73f4459 AB |
268 | if (vol_id >= 0) |
269 | ret = ubi_open_volume(ubi_num, vol_id, mode); | |
270 | else | |
271 | ret = ERR_PTR(-ENODEV); | |
801c135c | 272 | |
e73f4459 AB |
273 | /* |
274 | * We should put the UBI device even in case of success, because | |
275 | * 'ubi_open_volume()' took a reference as well. | |
276 | */ | |
277 | ubi_put_device(ubi); | |
278 | return ret; | |
801c135c AB |
279 | } |
280 | EXPORT_SYMBOL_GPL(ubi_open_volume_nm); | |
281 | ||
762d73cd DG |
282 | /** |
283 | * ubi_get_num_by_path - get UBI device and volume number from device path | |
284 | * @pathname: volume character device node path | |
285 | * @ubi_num: pointer to UBI device number to be set | |
286 | * @vol_id: pointer to UBI volume ID to be set | |
287 | * | |
288 | * Returns 0 on success and sets ubi_num and vol_id, returns error otherwise. | |
289 | */ | |
290 | int ubi_get_num_by_path(const char *pathname, int *ubi_num, int *vol_id) | |
291 | { | |
292 | int error; | |
293 | struct path path; | |
294 | struct kstat stat; | |
295 | ||
296 | error = kern_path(pathname, LOOKUP_FOLLOW, &path); | |
297 | if (error) | |
298 | return error; | |
299 | ||
300 | error = vfs_getattr(&path, &stat, STATX_TYPE, AT_STATX_SYNC_AS_STAT); | |
301 | path_put(&path); | |
302 | if (error) | |
303 | return error; | |
304 | ||
305 | if (!S_ISCHR(stat.mode)) | |
306 | return -EINVAL; | |
307 | ||
308 | *ubi_num = ubi_major2num(MAJOR(stat.rdev)); | |
309 | *vol_id = MINOR(stat.rdev) - 1; | |
310 | ||
311 | if (*vol_id < 0 || *ubi_num < 0) | |
312 | return -ENODEV; | |
313 | ||
314 | return 0; | |
315 | } | |
316 | ||
b5710284 CC |
317 | /** |
318 | * ubi_open_volume_path - open UBI volume by its character device node path. | |
319 | * @pathname: volume character device node path | |
320 | * @mode: open mode | |
321 | * | |
322 | * This function is similar to 'ubi_open_volume()', but opens a volume the path | |
323 | * to its character device node. | |
324 | */ | |
325 | struct ubi_volume_desc *ubi_open_volume_path(const char *pathname, int mode) | |
326 | { | |
61edc3f3 | 327 | int error, ubi_num, vol_id; |
b5710284 CC |
328 | |
329 | dbg_gen("open volume %s, mode %d", pathname, mode); | |
330 | ||
331 | if (!pathname || !*pathname) | |
332 | return ERR_PTR(-EINVAL); | |
333 | ||
762d73cd | 334 | error = ubi_get_num_by_path(pathname, &ubi_num, &vol_id); |
61edc3f3 RW |
335 | if (error) |
336 | return ERR_PTR(error); | |
322ea0bb | 337 | |
762d73cd | 338 | return ubi_open_volume(ubi_num, vol_id, mode); |
b5710284 CC |
339 | } |
340 | EXPORT_SYMBOL_GPL(ubi_open_volume_path); | |
341 | ||
801c135c AB |
342 | /** |
343 | * ubi_close_volume - close UBI volume. | |
344 | * @desc: volume descriptor | |
345 | */ | |
346 | void ubi_close_volume(struct ubi_volume_desc *desc) | |
347 | { | |
348 | struct ubi_volume *vol = desc->vol; | |
e73f4459 | 349 | struct ubi_device *ubi = vol->ubi; |
801c135c | 350 | |
e1cf7e6d AB |
351 | dbg_gen("close device %d, volume %d, mode %d", |
352 | ubi->ubi_num, vol->vol_id, desc->mode); | |
801c135c | 353 | |
e73f4459 | 354 | spin_lock(&ubi->volumes_lock); |
801c135c AB |
355 | switch (desc->mode) { |
356 | case UBI_READONLY: | |
357 | vol->readers -= 1; | |
358 | break; | |
359 | case UBI_READWRITE: | |
360 | vol->writers -= 1; | |
361 | break; | |
362 | case UBI_EXCLUSIVE: | |
363 | vol->exclusive = 0; | |
fafdd2bf RW |
364 | break; |
365 | case UBI_METAONLY: | |
366 | vol->metaonly = 0; | |
367 | break; | |
801c135c | 368 | } |
d05c77a8 | 369 | vol->ref_count -= 1; |
e73f4459 | 370 | spin_unlock(&ubi->volumes_lock); |
801c135c | 371 | |
d05c77a8 | 372 | kfree(desc); |
e73f4459 AB |
373 | put_device(&vol->dev); |
374 | ubi_put_device(ubi); | |
801c135c AB |
375 | module_put(THIS_MODULE); |
376 | } | |
377 | EXPORT_SYMBOL_GPL(ubi_close_volume); | |
378 | ||
9ff08979 RW |
379 | /** |
380 | * leb_read_sanity_check - does sanity checks on read requests. | |
381 | * @desc: volume descriptor | |
382 | * @lnum: logical eraseblock number to read from | |
383 | * @offset: offset within the logical eraseblock to read from | |
384 | * @len: how many bytes to read | |
385 | * | |
386 | * This function is used by ubi_leb_read() and ubi_leb_read_sg() | |
387 | * to perform sanity checks. | |
388 | */ | |
389 | static int leb_read_sanity_check(struct ubi_volume_desc *desc, int lnum, | |
390 | int offset, int len) | |
391 | { | |
392 | struct ubi_volume *vol = desc->vol; | |
393 | struct ubi_device *ubi = vol->ubi; | |
394 | int vol_id = vol->vol_id; | |
395 | ||
396 | if (vol_id < 0 || vol_id >= ubi->vtbl_slots || lnum < 0 || | |
397 | lnum >= vol->used_ebs || offset < 0 || len < 0 || | |
398 | offset + len > vol->usable_leb_size) | |
399 | return -EINVAL; | |
400 | ||
401 | if (vol->vol_type == UBI_STATIC_VOLUME) { | |
402 | if (vol->used_ebs == 0) | |
403 | /* Empty static UBI volume */ | |
404 | return 0; | |
405 | if (lnum == vol->used_ebs - 1 && | |
406 | offset + len > vol->last_eb_bytes) | |
407 | return -EINVAL; | |
408 | } | |
409 | ||
410 | if (vol->upd_marker) | |
411 | return -EBADF; | |
412 | ||
413 | return 0; | |
414 | } | |
415 | ||
801c135c AB |
416 | /** |
417 | * ubi_leb_read - read data. | |
418 | * @desc: volume descriptor | |
419 | * @lnum: logical eraseblock number to read from | |
420 | * @buf: buffer where to store the read data | |
421 | * @offset: offset within the logical eraseblock to read from | |
422 | * @len: how many bytes to read | |
423 | * @check: whether UBI has to check the read data's CRC or not. | |
424 | * | |
425 | * This function reads data from offset @offset of logical eraseblock @lnum and | |
426 | * stores the data at @buf. When reading from static volumes, @check specifies | |
427 | * whether the data has to be checked or not. If yes, the whole logical | |
428 | * eraseblock will be read and its CRC checksum will be checked (i.e., the CRC | |
429 | * checksum is per-eraseblock). So checking may substantially slow down the | |
430 | * read speed. The @check argument is ignored for dynamic volumes. | |
431 | * | |
432 | * In case of success, this function returns zero. In case of failure, this | |
433 | * function returns a negative error code. | |
434 | * | |
435 | * %-EBADMSG error code is returned: | |
436 | * o for both static and dynamic volumes if MTD driver has detected a data | |
437 | * integrity problem (unrecoverable ECC checksum mismatch in case of NAND); | |
438 | * o for static volumes in case of data CRC mismatch. | |
439 | * | |
440 | * If the volume is damaged because of an interrupted update this function just | |
441 | * returns immediately with %-EBADF error code. | |
442 | */ | |
443 | int ubi_leb_read(struct ubi_volume_desc *desc, int lnum, char *buf, int offset, | |
444 | int len, int check) | |
445 | { | |
446 | struct ubi_volume *vol = desc->vol; | |
447 | struct ubi_device *ubi = vol->ubi; | |
448 | int err, vol_id = vol->vol_id; | |
449 | ||
c8566350 | 450 | dbg_gen("read %d bytes from LEB %d:%d:%d", len, vol_id, lnum, offset); |
801c135c | 451 | |
9ff08979 RW |
452 | err = leb_read_sanity_check(desc, lnum, offset, len); |
453 | if (err < 0) | |
454 | return err; | |
801c135c | 455 | |
801c135c AB |
456 | if (len == 0) |
457 | return 0; | |
458 | ||
89b96b69 | 459 | err = ubi_eba_read_leb(ubi, vol, lnum, buf, offset, len, check); |
d57f4054 | 460 | if (err && mtd_is_eccerr(err) && vol->vol_type == UBI_STATIC_VOLUME) { |
32608703 | 461 | ubi_warn(ubi, "mark volume %d as corrupted", vol_id); |
801c135c AB |
462 | vol->corrupted = 1; |
463 | } | |
464 | ||
465 | return err; | |
466 | } | |
467 | EXPORT_SYMBOL_GPL(ubi_leb_read); | |
468 | ||
9ff08979 RW |
469 | |
470 | /** | |
471 | * ubi_leb_read_sg - read data into a scatter gather list. | |
472 | * @desc: volume descriptor | |
473 | * @lnum: logical eraseblock number to read from | |
b6baa996 | 474 | * @sgl: UBI scatter gather list to store the read data |
9ff08979 RW |
475 | * @offset: offset within the logical eraseblock to read from |
476 | * @len: how many bytes to read | |
477 | * @check: whether UBI has to check the read data's CRC or not. | |
478 | * | |
479 | * This function works exactly like ubi_leb_read_sg(). But instead of | |
480 | * storing the read data into a buffer it writes to an UBI scatter gather | |
481 | * list. | |
482 | */ | |
483 | int ubi_leb_read_sg(struct ubi_volume_desc *desc, int lnum, struct ubi_sgl *sgl, | |
484 | int offset, int len, int check) | |
485 | { | |
486 | struct ubi_volume *vol = desc->vol; | |
487 | struct ubi_device *ubi = vol->ubi; | |
488 | int err, vol_id = vol->vol_id; | |
489 | ||
490 | dbg_gen("read %d bytes from LEB %d:%d:%d", len, vol_id, lnum, offset); | |
491 | ||
492 | err = leb_read_sanity_check(desc, lnum, offset, len); | |
493 | if (err < 0) | |
494 | return err; | |
495 | ||
496 | if (len == 0) | |
497 | return 0; | |
498 | ||
499 | err = ubi_eba_read_leb_sg(ubi, vol, sgl, lnum, offset, len, check); | |
500 | if (err && mtd_is_eccerr(err) && vol->vol_type == UBI_STATIC_VOLUME) { | |
501 | ubi_warn(ubi, "mark volume %d as corrupted", vol_id); | |
502 | vol->corrupted = 1; | |
503 | } | |
504 | ||
505 | return err; | |
506 | } | |
507 | EXPORT_SYMBOL_GPL(ubi_leb_read_sg); | |
508 | ||
801c135c AB |
509 | /** |
510 | * ubi_leb_write - write data. | |
511 | * @desc: volume descriptor | |
512 | * @lnum: logical eraseblock number to write to | |
513 | * @buf: data to write | |
514 | * @offset: offset within the logical eraseblock where to write | |
515 | * @len: how many bytes to write | |
801c135c AB |
516 | * |
517 | * This function writes @len bytes of data from @buf to offset @offset of | |
b36a261e | 518 | * logical eraseblock @lnum. |
801c135c AB |
519 | * |
520 | * This function takes care of physical eraseblock write failures. If write to | |
521 | * the physical eraseblock write operation fails, the logical eraseblock is | |
522 | * re-mapped to another physical eraseblock, the data is recovered, and the | |
523 | * write finishes. UBI has a pool of reserved physical eraseblocks for this. | |
524 | * | |
525 | * If all the data were successfully written, zero is returned. If an error | |
526 | * occurred and UBI has not been able to recover from it, this function returns | |
527 | * a negative error code. Note, in case of an error, it is possible that | |
528 | * something was still written to the flash media, but that may be some | |
529 | * garbage. | |
530 | * | |
531 | * If the volume is damaged because of an interrupted update this function just | |
532 | * returns immediately with %-EBADF code. | |
533 | */ | |
534 | int ubi_leb_write(struct ubi_volume_desc *desc, int lnum, const void *buf, | |
b36a261e | 535 | int offset, int len) |
801c135c AB |
536 | { |
537 | struct ubi_volume *vol = desc->vol; | |
538 | struct ubi_device *ubi = vol->ubi; | |
539 | int vol_id = vol->vol_id; | |
540 | ||
c8566350 | 541 | dbg_gen("write %d bytes to LEB %d:%d:%d", len, vol_id, lnum, offset); |
801c135c AB |
542 | |
543 | if (vol_id < 0 || vol_id >= ubi->vtbl_slots) | |
544 | return -EINVAL; | |
545 | ||
546 | if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME) | |
547 | return -EROFS; | |
548 | ||
9a5f09ac | 549 | if (!ubi_leb_valid(vol, lnum) || offset < 0 || len < 0 || |
cadb40cc KP |
550 | offset + len > vol->usable_leb_size || |
551 | offset & (ubi->min_io_size - 1) || len & (ubi->min_io_size - 1)) | |
801c135c AB |
552 | return -EINVAL; |
553 | ||
801c135c AB |
554 | if (vol->upd_marker) |
555 | return -EBADF; | |
556 | ||
557 | if (len == 0) | |
558 | return 0; | |
559 | ||
b36a261e | 560 | return ubi_eba_write_leb(ubi, vol, lnum, buf, offset, len); |
801c135c AB |
561 | } |
562 | EXPORT_SYMBOL_GPL(ubi_leb_write); | |
563 | ||
564 | /* | |
565 | * ubi_leb_change - change logical eraseblock atomically. | |
566 | * @desc: volume descriptor | |
567 | * @lnum: logical eraseblock number to change | |
568 | * @buf: data to write | |
569 | * @len: how many bytes to write | |
801c135c AB |
570 | * |
571 | * This function changes the contents of a logical eraseblock atomically. @buf | |
572 | * has to contain new logical eraseblock data, and @len - the length of the | |
3f502622 | 573 | * data, which has to be aligned. The length may be shorter than the logical |
801c135c AB |
574 | * eraseblock size, ant the logical eraseblock may be appended to more times |
575 | * later on. This function guarantees that in case of an unclean reboot the old | |
576 | * contents is preserved. Returns zero in case of success and a negative error | |
577 | * code in case of failure. | |
578 | */ | |
579 | int ubi_leb_change(struct ubi_volume_desc *desc, int lnum, const void *buf, | |
b36a261e | 580 | int len) |
801c135c AB |
581 | { |
582 | struct ubi_volume *vol = desc->vol; | |
583 | struct ubi_device *ubi = vol->ubi; | |
584 | int vol_id = vol->vol_id; | |
585 | ||
c8566350 | 586 | dbg_gen("atomically write %d bytes to LEB %d:%d", len, vol_id, lnum); |
801c135c AB |
587 | |
588 | if (vol_id < 0 || vol_id >= ubi->vtbl_slots) | |
589 | return -EINVAL; | |
590 | ||
591 | if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME) | |
592 | return -EROFS; | |
593 | ||
9a5f09ac | 594 | if (!ubi_leb_valid(vol, lnum) || len < 0 || |
cadb40cc | 595 | len > vol->usable_leb_size || len & (ubi->min_io_size - 1)) |
801c135c AB |
596 | return -EINVAL; |
597 | ||
801c135c AB |
598 | if (vol->upd_marker) |
599 | return -EBADF; | |
600 | ||
601 | if (len == 0) | |
602 | return 0; | |
603 | ||
b36a261e | 604 | return ubi_eba_atomic_leb_change(ubi, vol, lnum, buf, len); |
801c135c AB |
605 | } |
606 | EXPORT_SYMBOL_GPL(ubi_leb_change); | |
607 | ||
608 | /** | |
609 | * ubi_leb_erase - erase logical eraseblock. | |
610 | * @desc: volume descriptor | |
611 | * @lnum: logical eraseblock number | |
612 | * | |
613 | * This function un-maps logical eraseblock @lnum and synchronously erases the | |
614 | * correspondent physical eraseblock. Returns zero in case of success and a | |
615 | * negative error code in case of failure. | |
616 | * | |
617 | * If the volume is damaged because of an interrupted update this function just | |
618 | * returns immediately with %-EBADF code. | |
619 | */ | |
620 | int ubi_leb_erase(struct ubi_volume_desc *desc, int lnum) | |
621 | { | |
622 | struct ubi_volume *vol = desc->vol; | |
623 | struct ubi_device *ubi = vol->ubi; | |
ae616e1b | 624 | int err; |
801c135c | 625 | |
c8566350 | 626 | dbg_gen("erase LEB %d:%d", vol->vol_id, lnum); |
801c135c AB |
627 | |
628 | if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME) | |
629 | return -EROFS; | |
630 | ||
9a5f09ac | 631 | if (!ubi_leb_valid(vol, lnum)) |
801c135c AB |
632 | return -EINVAL; |
633 | ||
634 | if (vol->upd_marker) | |
635 | return -EBADF; | |
636 | ||
89b96b69 | 637 | err = ubi_eba_unmap_leb(ubi, vol, lnum); |
801c135c AB |
638 | if (err) |
639 | return err; | |
640 | ||
62f38455 | 641 | return ubi_wl_flush(ubi, vol->vol_id, lnum); |
801c135c AB |
642 | } |
643 | EXPORT_SYMBOL_GPL(ubi_leb_erase); | |
644 | ||
645 | /** | |
646 | * ubi_leb_unmap - un-map logical eraseblock. | |
647 | * @desc: volume descriptor | |
648 | * @lnum: logical eraseblock number | |
649 | * | |
650 | * This function un-maps logical eraseblock @lnum and schedules the | |
651 | * corresponding physical eraseblock for erasure, so that it will eventually be | |
3f502622 | 652 | * physically erased in background. This operation is much faster than the |
801c135c AB |
653 | * erase operation. |
654 | * | |
655 | * Unlike erase, the un-map operation does not guarantee that the logical | |
656 | * eraseblock will contain all 0xFF bytes when UBI is initialized again. For | |
657 | * example, if several logical eraseblocks are un-mapped, and an unclean reboot | |
658 | * happens after this, the logical eraseblocks will not necessarily be | |
659 | * un-mapped again when this MTD device is attached. They may actually be | |
660 | * mapped to the same physical eraseblocks again. So, this function has to be | |
661 | * used with care. | |
662 | * | |
663 | * In other words, when un-mapping a logical eraseblock, UBI does not store | |
664 | * any information about this on the flash media, it just marks the logical | |
665 | * eraseblock as "un-mapped" in RAM. If UBI is detached before the physical | |
666 | * eraseblock is physically erased, it will be mapped again to the same logical | |
667 | * eraseblock when the MTD device is attached again. | |
668 | * | |
669 | * The main and obvious use-case of this function is when the contents of a | |
670 | * logical eraseblock has to be re-written. Then it is much more efficient to | |
3f502622 | 671 | * first un-map it, then write new data, rather than first erase it, then write |
801c135c AB |
672 | * new data. Note, once new data has been written to the logical eraseblock, |
673 | * UBI guarantees that the old contents has gone forever. In other words, if an | |
674 | * unclean reboot happens after the logical eraseblock has been un-mapped and | |
675 | * then written to, it will contain the last written data. | |
676 | * | |
677 | * This function returns zero in case of success and a negative error code in | |
678 | * case of failure. If the volume is damaged because of an interrupted update | |
679 | * this function just returns immediately with %-EBADF code. | |
680 | */ | |
681 | int ubi_leb_unmap(struct ubi_volume_desc *desc, int lnum) | |
682 | { | |
683 | struct ubi_volume *vol = desc->vol; | |
684 | struct ubi_device *ubi = vol->ubi; | |
801c135c | 685 | |
c8566350 | 686 | dbg_gen("unmap LEB %d:%d", vol->vol_id, lnum); |
801c135c AB |
687 | |
688 | if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME) | |
689 | return -EROFS; | |
690 | ||
9a5f09ac | 691 | if (!ubi_leb_valid(vol, lnum)) |
801c135c AB |
692 | return -EINVAL; |
693 | ||
694 | if (vol->upd_marker) | |
695 | return -EBADF; | |
696 | ||
89b96b69 | 697 | return ubi_eba_unmap_leb(ubi, vol, lnum); |
801c135c AB |
698 | } |
699 | EXPORT_SYMBOL_GPL(ubi_leb_unmap); | |
393852ec AB |
700 | |
701 | /** | |
0e0ee1cc | 702 | * ubi_leb_map - map logical eraseblock to a physical eraseblock. |
393852ec AB |
703 | * @desc: volume descriptor |
704 | * @lnum: logical eraseblock number | |
393852ec AB |
705 | * |
706 | * This function maps an un-mapped logical eraseblock @lnum to a physical | |
73ac36ea | 707 | * eraseblock. This means, that after a successful invocation of this |
393852ec AB |
708 | * function the logical eraseblock @lnum will be empty (contain only %0xFF |
709 | * bytes) and be mapped to a physical eraseblock, even if an unclean reboot | |
710 | * happens. | |
711 | * | |
712 | * This function returns zero in case of success, %-EBADF if the volume is | |
713 | * damaged because of an interrupted update, %-EBADMSG if the logical | |
714 | * eraseblock is already mapped, and other negative error codes in case of | |
715 | * other failures. | |
716 | */ | |
b36a261e | 717 | int ubi_leb_map(struct ubi_volume_desc *desc, int lnum) |
393852ec AB |
718 | { |
719 | struct ubi_volume *vol = desc->vol; | |
720 | struct ubi_device *ubi = vol->ubi; | |
393852ec | 721 | |
960b35d0 | 722 | dbg_gen("map LEB %d:%d", vol->vol_id, lnum); |
393852ec AB |
723 | |
724 | if (desc->mode == UBI_READONLY || vol->vol_type == UBI_STATIC_VOLUME) | |
725 | return -EROFS; | |
726 | ||
9a5f09ac | 727 | if (!ubi_leb_valid(vol, lnum)) |
393852ec AB |
728 | return -EINVAL; |
729 | ||
393852ec AB |
730 | if (vol->upd_marker) |
731 | return -EBADF; | |
732 | ||
75547696 | 733 | if (ubi_eba_is_mapped(vol, lnum)) |
393852ec AB |
734 | return -EBADMSG; |
735 | ||
b36a261e | 736 | return ubi_eba_write_leb(ubi, vol, lnum, NULL, 0, 0); |
393852ec AB |
737 | } |
738 | EXPORT_SYMBOL_GPL(ubi_leb_map); | |
801c135c AB |
739 | |
740 | /** | |
741 | * ubi_is_mapped - check if logical eraseblock is mapped. | |
742 | * @desc: volume descriptor | |
743 | * @lnum: logical eraseblock number | |
744 | * | |
745 | * This function checks if logical eraseblock @lnum is mapped to a physical | |
746 | * eraseblock. If a logical eraseblock is un-mapped, this does not necessarily | |
747 | * mean it will still be un-mapped after the UBI device is re-attached. The | |
748 | * logical eraseblock may become mapped to the physical eraseblock it was last | |
749 | * mapped to. | |
750 | * | |
751 | * This function returns %1 if the LEB is mapped, %0 if not, and a negative | |
752 | * error code in case of failure. If the volume is damaged because of an | |
753 | * interrupted update this function just returns immediately with %-EBADF error | |
754 | * code. | |
755 | */ | |
756 | int ubi_is_mapped(struct ubi_volume_desc *desc, int lnum) | |
757 | { | |
758 | struct ubi_volume *vol = desc->vol; | |
759 | ||
c8566350 | 760 | dbg_gen("test LEB %d:%d", vol->vol_id, lnum); |
801c135c | 761 | |
9a5f09ac | 762 | if (!ubi_leb_valid(vol, lnum)) |
801c135c AB |
763 | return -EINVAL; |
764 | ||
765 | if (vol->upd_marker) | |
766 | return -EBADF; | |
767 | ||
75547696 | 768 | return ubi_eba_is_mapped(vol, lnum); |
801c135c AB |
769 | } |
770 | EXPORT_SYMBOL_GPL(ubi_is_mapped); | |
a5bf6190 AB |
771 | |
772 | /** | |
773 | * ubi_sync - synchronize UBI device buffers. | |
774 | * @ubi_num: UBI device to synchronize | |
775 | * | |
776 | * The underlying MTD device may cache data in hardware or in software. This | |
777 | * function ensures the caches are flushed. Returns zero in case of success and | |
778 | * a negative error code in case of failure. | |
779 | */ | |
780 | int ubi_sync(int ubi_num) | |
781 | { | |
782 | struct ubi_device *ubi; | |
783 | ||
784 | ubi = ubi_get_device(ubi_num); | |
785 | if (!ubi) | |
786 | return -ENODEV; | |
787 | ||
327cf292 | 788 | mtd_sync(ubi->mtd); |
a5bf6190 AB |
789 | ubi_put_device(ubi); |
790 | return 0; | |
791 | } | |
792 | EXPORT_SYMBOL_GPL(ubi_sync); | |
0e0ee1cc | 793 | |
62f38455 JR |
794 | /** |
795 | * ubi_flush - flush UBI work queue. | |
796 | * @ubi_num: UBI device to flush work queue | |
797 | * @vol_id: volume id to flush for | |
798 | * @lnum: logical eraseblock number to flush for | |
799 | * | |
800 | * This function executes all pending works for a particular volume id / logical | |
801 | * eraseblock number pair. If either value is set to %UBI_ALL, then it acts as | |
802 | * a wildcard for all of the corresponding volume numbers or logical | |
803 | * eraseblock numbers. It returns zero in case of success and a negative error | |
804 | * code in case of failure. | |
805 | */ | |
806 | int ubi_flush(int ubi_num, int vol_id, int lnum) | |
807 | { | |
808 | struct ubi_device *ubi; | |
809 | int err = 0; | |
810 | ||
811 | ubi = ubi_get_device(ubi_num); | |
812 | if (!ubi) | |
813 | return -ENODEV; | |
814 | ||
815 | err = ubi_wl_flush(ubi, vol_id, lnum); | |
816 | ubi_put_device(ubi); | |
817 | return err; | |
818 | } | |
819 | EXPORT_SYMBOL_GPL(ubi_flush); | |
820 | ||
0e0ee1cc DP |
821 | BLOCKING_NOTIFIER_HEAD(ubi_notifiers); |
822 | ||
823 | /** | |
824 | * ubi_register_volume_notifier - register a volume notifier. | |
825 | * @nb: the notifier description object | |
826 | * @ignore_existing: if non-zero, do not send "added" notification for all | |
827 | * already existing volumes | |
828 | * | |
829 | * This function registers a volume notifier, which means that | |
830 | * 'nb->notifier_call()' will be invoked when an UBI volume is created, | |
831 | * removed, re-sized, re-named, or updated. The first argument of the function | |
832 | * is the notification type. The second argument is pointer to a | |
833 | * &struct ubi_notification object which describes the notification event. | |
834 | * Using UBI API from the volume notifier is prohibited. | |
835 | * | |
836 | * This function returns zero in case of success and a negative error code | |
837 | * in case of failure. | |
838 | */ | |
839 | int ubi_register_volume_notifier(struct notifier_block *nb, | |
840 | int ignore_existing) | |
841 | { | |
842 | int err; | |
843 | ||
844 | err = blocking_notifier_chain_register(&ubi_notifiers, nb); | |
845 | if (err != 0) | |
846 | return err; | |
847 | if (ignore_existing) | |
848 | return 0; | |
849 | ||
850 | /* | |
851 | * We are going to walk all UBI devices and all volumes, and | |
852 | * notify the user about existing volumes by the %UBI_VOLUME_ADDED | |
853 | * event. We have to lock the @ubi_devices_mutex to make sure UBI | |
854 | * devices do not disappear. | |
855 | */ | |
856 | mutex_lock(&ubi_devices_mutex); | |
857 | ubi_enumerate_volumes(nb); | |
858 | mutex_unlock(&ubi_devices_mutex); | |
859 | ||
860 | return err; | |
861 | } | |
862 | EXPORT_SYMBOL_GPL(ubi_register_volume_notifier); | |
863 | ||
864 | /** | |
865 | * ubi_unregister_volume_notifier - unregister the volume notifier. | |
866 | * @nb: the notifier description object | |
867 | * | |
868 | * This function unregisters volume notifier @nm and returns zero in case of | |
869 | * success and a negative error code in case of failure. | |
870 | */ | |
871 | int ubi_unregister_volume_notifier(struct notifier_block *nb) | |
872 | { | |
873 | return blocking_notifier_chain_unregister(&ubi_notifiers, nb); | |
874 | } | |
875 | EXPORT_SYMBOL_GPL(ubi_unregister_volume_notifier); |