Commit | Line | Data |
---|---|---|
801c135c AB |
1 | /* |
2 | * Copyright (c) International Business Machines Corp., 2006 | |
3 | * Copyright (c) Nokia Corporation, 2006, 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 | */ | |
21 | ||
22 | /* | |
85c6e6e2 | 23 | * UBI input/output sub-system. |
801c135c | 24 | * |
85c6e6e2 AB |
25 | * This sub-system provides a uniform way to work with all kinds of the |
26 | * underlying MTD devices. It also implements handy functions for reading and | |
27 | * writing UBI headers. | |
801c135c AB |
28 | * |
29 | * We are trying to have a paranoid mindset and not to trust to what we read | |
85c6e6e2 AB |
30 | * from the flash media in order to be more secure and robust. So this |
31 | * sub-system validates every single header it reads from the flash media. | |
801c135c AB |
32 | * |
33 | * Some words about how the eraseblock headers are stored. | |
34 | * | |
35 | * The erase counter header is always stored at offset zero. By default, the | |
36 | * VID header is stored after the EC header at the closest aligned offset | |
37 | * (i.e. aligned to the minimum I/O unit size). Data starts next to the VID | |
38 | * header at the closest aligned offset. But this default layout may be | |
39 | * changed. For example, for different reasons (e.g., optimization) UBI may be | |
40 | * asked to put the VID header at further offset, and even at an unaligned | |
41 | * offset. Of course, if the offset of the VID header is unaligned, UBI adds | |
42 | * proper padding in front of it. Data offset may also be changed but it has to | |
43 | * be aligned. | |
44 | * | |
45 | * About minimal I/O units. In general, UBI assumes flash device model where | |
46 | * there is only one minimal I/O unit size. E.g., in case of NOR flash it is 1, | |
47 | * in case of NAND flash it is a NAND page, etc. This is reported by MTD in the | |
48 | * @ubi->mtd->writesize field. But as an exception, UBI admits of using another | |
49 | * (smaller) minimal I/O unit size for EC and VID headers to make it possible | |
50 | * to do different optimizations. | |
51 | * | |
52 | * This is extremely useful in case of NAND flashes which admit of several | |
53 | * write operations to one NAND page. In this case UBI can fit EC and VID | |
54 | * headers at one NAND page. Thus, UBI may use "sub-page" size as the minimal | |
55 | * I/O unit for the headers (the @ubi->hdrs_min_io_size field). But it still | |
56 | * reports NAND page size (@ubi->min_io_size) as a minimal I/O unit for the UBI | |
57 | * users. | |
58 | * | |
59 | * Example: some Samsung NANDs with 2KiB pages allow 4x 512-byte writes, so | |
60 | * although the minimal I/O unit is 2K, UBI uses 512 bytes for EC and VID | |
61 | * headers. | |
62 | * | |
63 | * Q: why not just to treat sub-page as a minimal I/O unit of this flash | |
64 | * device, e.g., make @ubi->min_io_size = 512 in the example above? | |
65 | * | |
66 | * A: because when writing a sub-page, MTD still writes a full 2K page but the | |
67 | * bytes which are no relevant to the sub-page are 0xFF. So, basically, writing | |
68 | * 4x512 sub-pages is 4 times slower then writing one 2KiB NAND page. Thus, we | |
69 | * prefer to use sub-pages only for EV and VID headers. | |
70 | * | |
71 | * As it was noted above, the VID header may start at a non-aligned offset. | |
72 | * For example, in case of a 2KiB page NAND flash with a 512 bytes sub-page, | |
73 | * the VID header may reside at offset 1984 which is the last 64 bytes of the | |
74 | * last sub-page (EC header is always at offset zero). This causes some | |
75 | * difficulties when reading and writing VID headers. | |
76 | * | |
77 | * Suppose we have a 64-byte buffer and we read a VID header at it. We change | |
78 | * the data and want to write this VID header out. As we can only write in | |
79 | * 512-byte chunks, we have to allocate one more buffer and copy our VID header | |
80 | * to offset 448 of this buffer. | |
81 | * | |
85c6e6e2 AB |
82 | * The I/O sub-system does the following trick in order to avoid this extra |
83 | * copy. It always allocates a @ubi->vid_hdr_alsize bytes buffer for the VID | |
84 | * header and returns a pointer to offset @ubi->vid_hdr_shift of this buffer. | |
85 | * When the VID header is being written out, it shifts the VID header pointer | |
86 | * back and writes the whole sub-page. | |
801c135c AB |
87 | */ |
88 | ||
89 | #include <linux/crc32.h> | |
90 | #include <linux/err.h> | |
91 | #include "ubi.h" | |
92 | ||
93 | #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID | |
94 | static int paranoid_check_not_bad(const struct ubi_device *ubi, int pnum); | |
95 | static int paranoid_check_peb_ec_hdr(const struct ubi_device *ubi, int pnum); | |
96 | static int paranoid_check_ec_hdr(const struct ubi_device *ubi, int pnum, | |
97 | const struct ubi_ec_hdr *ec_hdr); | |
98 | static int paranoid_check_peb_vid_hdr(const struct ubi_device *ubi, int pnum); | |
99 | static int paranoid_check_vid_hdr(const struct ubi_device *ubi, int pnum, | |
100 | const struct ubi_vid_hdr *vid_hdr); | |
e88d6e10 AB |
101 | static int paranoid_check_all_ff(struct ubi_device *ubi, int pnum, int offset, |
102 | int len); | |
ffb6b7e4 | 103 | static int paranoid_check_empty(struct ubi_device *ubi, int pnum); |
801c135c AB |
104 | #else |
105 | #define paranoid_check_not_bad(ubi, pnum) 0 | |
106 | #define paranoid_check_peb_ec_hdr(ubi, pnum) 0 | |
107 | #define paranoid_check_ec_hdr(ubi, pnum, ec_hdr) 0 | |
108 | #define paranoid_check_peb_vid_hdr(ubi, pnum) 0 | |
109 | #define paranoid_check_vid_hdr(ubi, pnum, vid_hdr) 0 | |
110 | #define paranoid_check_all_ff(ubi, pnum, offset, len) 0 | |
ffb6b7e4 | 111 | #define paranoid_check_empty(ubi, pnum) 0 |
801c135c AB |
112 | #endif |
113 | ||
114 | /** | |
115 | * ubi_io_read - read data from a physical eraseblock. | |
116 | * @ubi: UBI device description object | |
117 | * @buf: buffer where to store the read data | |
118 | * @pnum: physical eraseblock number to read from | |
119 | * @offset: offset within the physical eraseblock from where to read | |
120 | * @len: how many bytes to read | |
121 | * | |
122 | * This function reads data from offset @offset of physical eraseblock @pnum | |
123 | * and stores the read data in the @buf buffer. The following return codes are | |
124 | * possible: | |
125 | * | |
126 | * o %0 if all the requested data were successfully read; | |
127 | * o %UBI_IO_BITFLIPS if all the requested data were successfully read, but | |
128 | * correctable bit-flips were detected; this is harmless but may indicate | |
129 | * that this eraseblock may become bad soon (but do not have to); | |
63b6c1ed AB |
130 | * o %-EBADMSG if the MTD subsystem reported about data integrity problems, for |
131 | * example it can be an ECC error in case of NAND; this most probably means | |
132 | * that the data is corrupted; | |
801c135c AB |
133 | * o %-EIO if some I/O error occurred; |
134 | * o other negative error codes in case of other errors. | |
135 | */ | |
136 | int ubi_io_read(const struct ubi_device *ubi, void *buf, int pnum, int offset, | |
137 | int len) | |
138 | { | |
139 | int err, retries = 0; | |
140 | size_t read; | |
141 | loff_t addr; | |
142 | ||
143 | dbg_io("read %d bytes from PEB %d:%d", len, pnum, offset); | |
144 | ||
145 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); | |
146 | ubi_assert(offset >= 0 && offset + len <= ubi->peb_size); | |
147 | ubi_assert(len > 0); | |
148 | ||
149 | err = paranoid_check_not_bad(ubi, pnum); | |
150 | if (err) | |
151 | return err > 0 ? -EINVAL : err; | |
152 | ||
153 | addr = (loff_t)pnum * ubi->peb_size + offset; | |
154 | retry: | |
155 | err = ubi->mtd->read(ubi->mtd, addr, len, &read, buf); | |
156 | if (err) { | |
157 | if (err == -EUCLEAN) { | |
158 | /* | |
159 | * -EUCLEAN is reported if there was a bit-flip which | |
160 | * was corrected, so this is harmless. | |
8c1e6ee1 AB |
161 | * |
162 | * We do not report about it here unless debugging is | |
163 | * enabled. A corresponding message will be printed | |
164 | * later, when it is has been scrubbed. | |
801c135c | 165 | */ |
8c1e6ee1 | 166 | dbg_msg("fixable bit-flip detected at PEB %d", pnum); |
801c135c AB |
167 | ubi_assert(len == read); |
168 | return UBI_IO_BITFLIPS; | |
169 | } | |
170 | ||
171 | if (read != len && retries++ < UBI_IO_RETRIES) { | |
9c9ec147 AB |
172 | dbg_io("error %d while reading %d bytes from PEB %d:%d," |
173 | " read only %zd bytes, retry", | |
801c135c AB |
174 | err, len, pnum, offset, read); |
175 | yield(); | |
176 | goto retry; | |
177 | } | |
178 | ||
179 | ubi_err("error %d while reading %d bytes from PEB %d:%d, " | |
180 | "read %zd bytes", err, len, pnum, offset, read); | |
181 | ubi_dbg_dump_stack(); | |
2362a53e AB |
182 | |
183 | /* | |
184 | * The driver should never return -EBADMSG if it failed to read | |
185 | * all the requested data. But some buggy drivers might do | |
186 | * this, so we change it to -EIO. | |
187 | */ | |
188 | if (read != len && err == -EBADMSG) { | |
189 | ubi_assert(0); | |
190 | err = -EIO; | |
191 | } | |
801c135c AB |
192 | } else { |
193 | ubi_assert(len == read); | |
194 | ||
195 | if (ubi_dbg_is_bitflip()) { | |
c8566350 | 196 | dbg_gen("bit-flip (emulated)"); |
801c135c AB |
197 | err = UBI_IO_BITFLIPS; |
198 | } | |
199 | } | |
200 | ||
201 | return err; | |
202 | } | |
203 | ||
204 | /** | |
205 | * ubi_io_write - write data to a physical eraseblock. | |
206 | * @ubi: UBI device description object | |
207 | * @buf: buffer with the data to write | |
208 | * @pnum: physical eraseblock number to write to | |
209 | * @offset: offset within the physical eraseblock where to write | |
210 | * @len: how many bytes to write | |
211 | * | |
212 | * This function writes @len bytes of data from buffer @buf to offset @offset | |
213 | * of physical eraseblock @pnum. If all the data were successfully written, | |
214 | * zero is returned. If an error occurred, this function returns a negative | |
215 | * error code. If %-EIO is returned, the physical eraseblock most probably went | |
216 | * bad. | |
217 | * | |
218 | * Note, in case of an error, it is possible that something was still written | |
219 | * to the flash media, but may be some garbage. | |
220 | */ | |
e88d6e10 AB |
221 | int ubi_io_write(struct ubi_device *ubi, const void *buf, int pnum, int offset, |
222 | int len) | |
801c135c AB |
223 | { |
224 | int err; | |
225 | size_t written; | |
226 | loff_t addr; | |
227 | ||
228 | dbg_io("write %d bytes to PEB %d:%d", len, pnum, offset); | |
229 | ||
230 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); | |
231 | ubi_assert(offset >= 0 && offset + len <= ubi->peb_size); | |
232 | ubi_assert(offset % ubi->hdrs_min_io_size == 0); | |
233 | ubi_assert(len > 0 && len % ubi->hdrs_min_io_size == 0); | |
234 | ||
235 | if (ubi->ro_mode) { | |
236 | ubi_err("read-only mode"); | |
237 | return -EROFS; | |
238 | } | |
239 | ||
240 | /* The below has to be compiled out if paranoid checks are disabled */ | |
241 | ||
242 | err = paranoid_check_not_bad(ubi, pnum); | |
243 | if (err) | |
244 | return err > 0 ? -EINVAL : err; | |
245 | ||
246 | /* The area we are writing to has to contain all 0xFF bytes */ | |
247 | err = paranoid_check_all_ff(ubi, pnum, offset, len); | |
248 | if (err) | |
249 | return err > 0 ? -EINVAL : err; | |
250 | ||
251 | if (offset >= ubi->leb_start) { | |
252 | /* | |
253 | * We write to the data area of the physical eraseblock. Make | |
254 | * sure it has valid EC and VID headers. | |
255 | */ | |
256 | err = paranoid_check_peb_ec_hdr(ubi, pnum); | |
257 | if (err) | |
258 | return err > 0 ? -EINVAL : err; | |
259 | err = paranoid_check_peb_vid_hdr(ubi, pnum); | |
260 | if (err) | |
261 | return err > 0 ? -EINVAL : err; | |
262 | } | |
263 | ||
264 | if (ubi_dbg_is_write_failure()) { | |
265 | dbg_err("cannot write %d bytes to PEB %d:%d " | |
266 | "(emulated)", len, pnum, offset); | |
267 | ubi_dbg_dump_stack(); | |
268 | return -EIO; | |
269 | } | |
270 | ||
271 | addr = (loff_t)pnum * ubi->peb_size + offset; | |
272 | err = ubi->mtd->write(ubi->mtd, addr, len, &written, buf); | |
273 | if (err) { | |
274 | ubi_err("error %d while writing %d bytes to PEB %d:%d, written" | |
275 | " %zd bytes", err, len, pnum, offset, written); | |
276 | ubi_dbg_dump_stack(); | |
277 | } else | |
278 | ubi_assert(written == len); | |
279 | ||
280 | return err; | |
281 | } | |
282 | ||
283 | /** | |
284 | * erase_callback - MTD erasure call-back. | |
285 | * @ei: MTD erase information object. | |
286 | * | |
287 | * Note, even though MTD erase interface is asynchronous, all the current | |
288 | * implementations are synchronous anyway. | |
289 | */ | |
290 | static void erase_callback(struct erase_info *ei) | |
291 | { | |
292 | wake_up_interruptible((wait_queue_head_t *)ei->priv); | |
293 | } | |
294 | ||
295 | /** | |
296 | * do_sync_erase - synchronously erase a physical eraseblock. | |
297 | * @ubi: UBI device description object | |
298 | * @pnum: the physical eraseblock number to erase | |
299 | * | |
300 | * This function synchronously erases physical eraseblock @pnum and returns | |
301 | * zero in case of success and a negative error code in case of failure. If | |
302 | * %-EIO is returned, the physical eraseblock most probably went bad. | |
303 | */ | |
e88d6e10 | 304 | static int do_sync_erase(struct ubi_device *ubi, int pnum) |
801c135c AB |
305 | { |
306 | int err, retries = 0; | |
307 | struct erase_info ei; | |
308 | wait_queue_head_t wq; | |
309 | ||
310 | dbg_io("erase PEB %d", pnum); | |
311 | ||
312 | retry: | |
313 | init_waitqueue_head(&wq); | |
314 | memset(&ei, 0, sizeof(struct erase_info)); | |
315 | ||
316 | ei.mtd = ubi->mtd; | |
2f176f79 | 317 | ei.addr = (loff_t)pnum * ubi->peb_size; |
801c135c AB |
318 | ei.len = ubi->peb_size; |
319 | ei.callback = erase_callback; | |
320 | ei.priv = (unsigned long)&wq; | |
321 | ||
322 | err = ubi->mtd->erase(ubi->mtd, &ei); | |
323 | if (err) { | |
324 | if (retries++ < UBI_IO_RETRIES) { | |
325 | dbg_io("error %d while erasing PEB %d, retry", | |
326 | err, pnum); | |
327 | yield(); | |
328 | goto retry; | |
329 | } | |
330 | ubi_err("cannot erase PEB %d, error %d", pnum, err); | |
331 | ubi_dbg_dump_stack(); | |
332 | return err; | |
333 | } | |
334 | ||
335 | err = wait_event_interruptible(wq, ei.state == MTD_ERASE_DONE || | |
336 | ei.state == MTD_ERASE_FAILED); | |
337 | if (err) { | |
338 | ubi_err("interrupted PEB %d erasure", pnum); | |
339 | return -EINTR; | |
340 | } | |
341 | ||
342 | if (ei.state == MTD_ERASE_FAILED) { | |
343 | if (retries++ < UBI_IO_RETRIES) { | |
344 | dbg_io("error while erasing PEB %d, retry", pnum); | |
345 | yield(); | |
346 | goto retry; | |
347 | } | |
348 | ubi_err("cannot erase PEB %d", pnum); | |
349 | ubi_dbg_dump_stack(); | |
350 | return -EIO; | |
351 | } | |
352 | ||
353 | err = paranoid_check_all_ff(ubi, pnum, 0, ubi->peb_size); | |
354 | if (err) | |
355 | return err > 0 ? -EINVAL : err; | |
356 | ||
357 | if (ubi_dbg_is_erase_failure() && !err) { | |
358 | dbg_err("cannot erase PEB %d (emulated)", pnum); | |
359 | return -EIO; | |
360 | } | |
361 | ||
362 | return 0; | |
363 | } | |
364 | ||
365 | /** | |
366 | * check_pattern - check if buffer contains only a certain byte pattern. | |
367 | * @buf: buffer to check | |
368 | * @patt: the pattern to check | |
369 | * @size: buffer size in bytes | |
370 | * | |
371 | * This function returns %1 in there are only @patt bytes in @buf, and %0 if | |
372 | * something else was also found. | |
373 | */ | |
374 | static int check_pattern(const void *buf, uint8_t patt, int size) | |
375 | { | |
376 | int i; | |
377 | ||
378 | for (i = 0; i < size; i++) | |
379 | if (((const uint8_t *)buf)[i] != patt) | |
380 | return 0; | |
381 | return 1; | |
382 | } | |
383 | ||
384 | /* Patterns to write to a physical eraseblock when torturing it */ | |
385 | static uint8_t patterns[] = {0xa5, 0x5a, 0x0}; | |
386 | ||
387 | /** | |
388 | * torture_peb - test a supposedly bad physical eraseblock. | |
389 | * @ubi: UBI device description object | |
390 | * @pnum: the physical eraseblock number to test | |
391 | * | |
392 | * This function returns %-EIO if the physical eraseblock did not pass the | |
393 | * test, a positive number of erase operations done if the test was | |
394 | * successfully passed, and other negative error codes in case of other errors. | |
395 | */ | |
e88d6e10 | 396 | static int torture_peb(struct ubi_device *ubi, int pnum) |
801c135c | 397 | { |
801c135c AB |
398 | int err, i, patt_count; |
399 | ||
8c1e6ee1 | 400 | ubi_msg("run torture test for PEB %d", pnum); |
801c135c AB |
401 | patt_count = ARRAY_SIZE(patterns); |
402 | ubi_assert(patt_count > 0); | |
403 | ||
e88d6e10 | 404 | mutex_lock(&ubi->buf_mutex); |
801c135c AB |
405 | for (i = 0; i < patt_count; i++) { |
406 | err = do_sync_erase(ubi, pnum); | |
407 | if (err) | |
408 | goto out; | |
409 | ||
410 | /* Make sure the PEB contains only 0xFF bytes */ | |
e88d6e10 | 411 | err = ubi_io_read(ubi, ubi->peb_buf1, pnum, 0, ubi->peb_size); |
801c135c AB |
412 | if (err) |
413 | goto out; | |
414 | ||
e88d6e10 | 415 | err = check_pattern(ubi->peb_buf1, 0xFF, ubi->peb_size); |
801c135c AB |
416 | if (err == 0) { |
417 | ubi_err("erased PEB %d, but a non-0xFF byte found", | |
418 | pnum); | |
419 | err = -EIO; | |
420 | goto out; | |
421 | } | |
422 | ||
423 | /* Write a pattern and check it */ | |
e88d6e10 AB |
424 | memset(ubi->peb_buf1, patterns[i], ubi->peb_size); |
425 | err = ubi_io_write(ubi, ubi->peb_buf1, pnum, 0, ubi->peb_size); | |
801c135c AB |
426 | if (err) |
427 | goto out; | |
428 | ||
e88d6e10 AB |
429 | memset(ubi->peb_buf1, ~patterns[i], ubi->peb_size); |
430 | err = ubi_io_read(ubi, ubi->peb_buf1, pnum, 0, ubi->peb_size); | |
801c135c AB |
431 | if (err) |
432 | goto out; | |
433 | ||
e88d6e10 | 434 | err = check_pattern(ubi->peb_buf1, patterns[i], ubi->peb_size); |
801c135c AB |
435 | if (err == 0) { |
436 | ubi_err("pattern %x checking failed for PEB %d", | |
437 | patterns[i], pnum); | |
438 | err = -EIO; | |
439 | goto out; | |
440 | } | |
441 | } | |
442 | ||
443 | err = patt_count; | |
8c1e6ee1 | 444 | ubi_msg("PEB %d passed torture test, do not mark it a bad", pnum); |
801c135c AB |
445 | |
446 | out: | |
e88d6e10 | 447 | mutex_unlock(&ubi->buf_mutex); |
8d2d4011 | 448 | if (err == UBI_IO_BITFLIPS || err == -EBADMSG) { |
801c135c AB |
449 | /* |
450 | * If a bit-flip or data integrity error was detected, the test | |
451 | * has not passed because it happened on a freshly erased | |
452 | * physical eraseblock which means something is wrong with it. | |
453 | */ | |
8d2d4011 AB |
454 | ubi_err("read problems on freshly erased PEB %d, must be bad", |
455 | pnum); | |
801c135c | 456 | err = -EIO; |
8d2d4011 | 457 | } |
801c135c AB |
458 | return err; |
459 | } | |
460 | ||
461 | /** | |
462 | * ubi_io_sync_erase - synchronously erase a physical eraseblock. | |
463 | * @ubi: UBI device description object | |
464 | * @pnum: physical eraseblock number to erase | |
465 | * @torture: if this physical eraseblock has to be tortured | |
466 | * | |
467 | * This function synchronously erases physical eraseblock @pnum. If @torture | |
468 | * flag is not zero, the physical eraseblock is checked by means of writing | |
469 | * different patterns to it and reading them back. If the torturing is enabled, | |
025dfdaf | 470 | * the physical eraseblock is erased more than once. |
801c135c AB |
471 | * |
472 | * This function returns the number of erasures made in case of success, %-EIO | |
473 | * if the erasure failed or the torturing test failed, and other negative error | |
474 | * codes in case of other errors. Note, %-EIO means that the physical | |
475 | * eraseblock is bad. | |
476 | */ | |
e88d6e10 | 477 | int ubi_io_sync_erase(struct ubi_device *ubi, int pnum, int torture) |
801c135c AB |
478 | { |
479 | int err, ret = 0; | |
480 | ||
481 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); | |
482 | ||
483 | err = paranoid_check_not_bad(ubi, pnum); | |
484 | if (err != 0) | |
485 | return err > 0 ? -EINVAL : err; | |
486 | ||
487 | if (ubi->ro_mode) { | |
488 | ubi_err("read-only mode"); | |
489 | return -EROFS; | |
490 | } | |
491 | ||
492 | if (torture) { | |
493 | ret = torture_peb(ubi, pnum); | |
494 | if (ret < 0) | |
495 | return ret; | |
496 | } | |
497 | ||
498 | err = do_sync_erase(ubi, pnum); | |
499 | if (err) | |
500 | return err; | |
501 | ||
502 | return ret + 1; | |
503 | } | |
504 | ||
505 | /** | |
506 | * ubi_io_is_bad - check if a physical eraseblock is bad. | |
507 | * @ubi: UBI device description object | |
508 | * @pnum: the physical eraseblock number to check | |
509 | * | |
510 | * This function returns a positive number if the physical eraseblock is bad, | |
511 | * zero if not, and a negative error code if an error occurred. | |
512 | */ | |
513 | int ubi_io_is_bad(const struct ubi_device *ubi, int pnum) | |
514 | { | |
515 | struct mtd_info *mtd = ubi->mtd; | |
516 | ||
517 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); | |
518 | ||
519 | if (ubi->bad_allowed) { | |
520 | int ret; | |
521 | ||
522 | ret = mtd->block_isbad(mtd, (loff_t)pnum * ubi->peb_size); | |
523 | if (ret < 0) | |
524 | ubi_err("error %d while checking if PEB %d is bad", | |
525 | ret, pnum); | |
526 | else if (ret) | |
527 | dbg_io("PEB %d is bad", pnum); | |
528 | return ret; | |
529 | } | |
530 | ||
531 | return 0; | |
532 | } | |
533 | ||
534 | /** | |
535 | * ubi_io_mark_bad - mark a physical eraseblock as bad. | |
536 | * @ubi: UBI device description object | |
537 | * @pnum: the physical eraseblock number to mark | |
538 | * | |
539 | * This function returns zero in case of success and a negative error code in | |
540 | * case of failure. | |
541 | */ | |
542 | int ubi_io_mark_bad(const struct ubi_device *ubi, int pnum) | |
543 | { | |
544 | int err; | |
545 | struct mtd_info *mtd = ubi->mtd; | |
546 | ||
547 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); | |
548 | ||
549 | if (ubi->ro_mode) { | |
550 | ubi_err("read-only mode"); | |
551 | return -EROFS; | |
552 | } | |
553 | ||
554 | if (!ubi->bad_allowed) | |
555 | return 0; | |
556 | ||
557 | err = mtd->block_markbad(mtd, (loff_t)pnum * ubi->peb_size); | |
558 | if (err) | |
559 | ubi_err("cannot mark PEB %d bad, error %d", pnum, err); | |
560 | return err; | |
561 | } | |
562 | ||
563 | /** | |
564 | * validate_ec_hdr - validate an erase counter header. | |
565 | * @ubi: UBI device description object | |
566 | * @ec_hdr: the erase counter header to check | |
567 | * | |
568 | * This function returns zero if the erase counter header is OK, and %1 if | |
569 | * not. | |
570 | */ | |
571 | static int validate_ec_hdr(const struct ubi_device *ubi, | |
572 | const struct ubi_ec_hdr *ec_hdr) | |
573 | { | |
574 | long long ec; | |
575 | int vid_hdr_offset, leb_start; | |
576 | ||
3261ebd7 CH |
577 | ec = be64_to_cpu(ec_hdr->ec); |
578 | vid_hdr_offset = be32_to_cpu(ec_hdr->vid_hdr_offset); | |
579 | leb_start = be32_to_cpu(ec_hdr->data_offset); | |
801c135c AB |
580 | |
581 | if (ec_hdr->version != UBI_VERSION) { | |
582 | ubi_err("node with incompatible UBI version found: " | |
583 | "this UBI version is %d, image version is %d", | |
584 | UBI_VERSION, (int)ec_hdr->version); | |
585 | goto bad; | |
586 | } | |
587 | ||
588 | if (vid_hdr_offset != ubi->vid_hdr_offset) { | |
589 | ubi_err("bad VID header offset %d, expected %d", | |
590 | vid_hdr_offset, ubi->vid_hdr_offset); | |
591 | goto bad; | |
592 | } | |
593 | ||
594 | if (leb_start != ubi->leb_start) { | |
595 | ubi_err("bad data offset %d, expected %d", | |
596 | leb_start, ubi->leb_start); | |
597 | goto bad; | |
598 | } | |
599 | ||
600 | if (ec < 0 || ec > UBI_MAX_ERASECOUNTER) { | |
601 | ubi_err("bad erase counter %lld", ec); | |
602 | goto bad; | |
603 | } | |
604 | ||
605 | return 0; | |
606 | ||
607 | bad: | |
608 | ubi_err("bad EC header"); | |
609 | ubi_dbg_dump_ec_hdr(ec_hdr); | |
610 | ubi_dbg_dump_stack(); | |
611 | return 1; | |
612 | } | |
613 | ||
614 | /** | |
615 | * ubi_io_read_ec_hdr - read and check an erase counter header. | |
616 | * @ubi: UBI device description object | |
617 | * @pnum: physical eraseblock to read from | |
618 | * @ec_hdr: a &struct ubi_ec_hdr object where to store the read erase counter | |
619 | * header | |
620 | * @verbose: be verbose if the header is corrupted or was not found | |
621 | * | |
622 | * This function reads erase counter header from physical eraseblock @pnum and | |
623 | * stores it in @ec_hdr. This function also checks CRC checksum of the read | |
624 | * erase counter header. The following codes may be returned: | |
625 | * | |
626 | * o %0 if the CRC checksum is correct and the header was successfully read; | |
627 | * o %UBI_IO_BITFLIPS if the CRC is correct, but bit-flips were detected | |
628 | * and corrected by the flash driver; this is harmless but may indicate that | |
629 | * this eraseblock may become bad soon (but may be not); | |
630 | * o %UBI_IO_BAD_EC_HDR if the erase counter header is corrupted (a CRC error); | |
631 | * o %UBI_IO_PEB_EMPTY if the physical eraseblock is empty; | |
632 | * o a negative error code in case of failure. | |
633 | */ | |
e88d6e10 | 634 | int ubi_io_read_ec_hdr(struct ubi_device *ubi, int pnum, |
801c135c AB |
635 | struct ubi_ec_hdr *ec_hdr, int verbose) |
636 | { | |
637 | int err, read_err = 0; | |
638 | uint32_t crc, magic, hdr_crc; | |
639 | ||
640 | dbg_io("read EC header from PEB %d", pnum); | |
641 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); | |
642 | ||
643 | err = ubi_io_read(ubi, ec_hdr, pnum, 0, UBI_EC_HDR_SIZE); | |
644 | if (err) { | |
645 | if (err != UBI_IO_BITFLIPS && err != -EBADMSG) | |
646 | return err; | |
647 | ||
648 | /* | |
649 | * We read all the data, but either a correctable bit-flip | |
650 | * occurred, or MTD reported about some data integrity error, | |
651 | * like an ECC error in case of NAND. The former is harmless, | |
652 | * the later may mean that the read data is corrupted. But we | |
653 | * have a CRC check-sum and we will detect this. If the EC | |
654 | * header is still OK, we just report this as there was a | |
655 | * bit-flip. | |
656 | */ | |
657 | read_err = err; | |
658 | } | |
659 | ||
3261ebd7 | 660 | magic = be32_to_cpu(ec_hdr->magic); |
801c135c AB |
661 | if (magic != UBI_EC_HDR_MAGIC) { |
662 | /* | |
663 | * The magic field is wrong. Let's check if we have read all | |
664 | * 0xFF. If yes, this physical eraseblock is assumed to be | |
665 | * empty. | |
666 | * | |
667 | * But if there was a read error, we do not test it for all | |
668 | * 0xFFs. Even if it does contain all 0xFFs, this error | |
669 | * indicates that something is still wrong with this physical | |
670 | * eraseblock and we anyway cannot treat it as empty. | |
671 | */ | |
672 | if (read_err != -EBADMSG && | |
673 | check_pattern(ec_hdr, 0xFF, UBI_EC_HDR_SIZE)) { | |
674 | /* The physical eraseblock is supposedly empty */ | |
801c135c AB |
675 | err = paranoid_check_all_ff(ubi, pnum, 0, |
676 | ubi->peb_size); | |
677 | if (err) | |
678 | return err > 0 ? UBI_IO_BAD_EC_HDR : err; | |
679 | ||
680 | if (verbose) | |
681 | ubi_warn("no EC header found at PEB %d, " | |
682 | "only 0xFF bytes", pnum); | |
ed45819f AB |
683 | else if (UBI_IO_DEBUG) |
684 | dbg_msg("no EC header found at PEB %d, " | |
685 | "only 0xFF bytes", pnum); | |
801c135c AB |
686 | return UBI_IO_PEB_EMPTY; |
687 | } | |
688 | ||
689 | /* | |
690 | * This is not a valid erase counter header, and these are not | |
691 | * 0xFF bytes. Report that the header is corrupted. | |
692 | */ | |
693 | if (verbose) { | |
694 | ubi_warn("bad magic number at PEB %d: %08x instead of " | |
695 | "%08x", pnum, magic, UBI_EC_HDR_MAGIC); | |
696 | ubi_dbg_dump_ec_hdr(ec_hdr); | |
ed45819f AB |
697 | } else if (UBI_IO_DEBUG) |
698 | dbg_msg("bad magic number at PEB %d: %08x instead of " | |
699 | "%08x", pnum, magic, UBI_EC_HDR_MAGIC); | |
801c135c AB |
700 | return UBI_IO_BAD_EC_HDR; |
701 | } | |
702 | ||
703 | crc = crc32(UBI_CRC32_INIT, ec_hdr, UBI_EC_HDR_SIZE_CRC); | |
3261ebd7 | 704 | hdr_crc = be32_to_cpu(ec_hdr->hdr_crc); |
801c135c AB |
705 | |
706 | if (hdr_crc != crc) { | |
707 | if (verbose) { | |
9c9ec147 AB |
708 | ubi_warn("bad EC header CRC at PEB %d, calculated " |
709 | "%#08x, read %#08x", pnum, crc, hdr_crc); | |
801c135c | 710 | ubi_dbg_dump_ec_hdr(ec_hdr); |
ed45819f AB |
711 | } else if (UBI_IO_DEBUG) |
712 | dbg_msg("bad EC header CRC at PEB %d, calculated " | |
713 | "%#08x, read %#08x", pnum, crc, hdr_crc); | |
801c135c AB |
714 | return UBI_IO_BAD_EC_HDR; |
715 | } | |
716 | ||
717 | /* And of course validate what has just been read from the media */ | |
718 | err = validate_ec_hdr(ubi, ec_hdr); | |
719 | if (err) { | |
720 | ubi_err("validation failed for PEB %d", pnum); | |
721 | return -EINVAL; | |
722 | } | |
723 | ||
724 | return read_err ? UBI_IO_BITFLIPS : 0; | |
725 | } | |
726 | ||
727 | /** | |
728 | * ubi_io_write_ec_hdr - write an erase counter header. | |
729 | * @ubi: UBI device description object | |
730 | * @pnum: physical eraseblock to write to | |
731 | * @ec_hdr: the erase counter header to write | |
732 | * | |
733 | * This function writes erase counter header described by @ec_hdr to physical | |
734 | * eraseblock @pnum. It also fills most fields of @ec_hdr before writing, so | |
735 | * the caller do not have to fill them. Callers must only fill the @ec_hdr->ec | |
736 | * field. | |
737 | * | |
738 | * This function returns zero in case of success and a negative error code in | |
739 | * case of failure. If %-EIO is returned, the physical eraseblock most probably | |
740 | * went bad. | |
741 | */ | |
e88d6e10 | 742 | int ubi_io_write_ec_hdr(struct ubi_device *ubi, int pnum, |
801c135c AB |
743 | struct ubi_ec_hdr *ec_hdr) |
744 | { | |
745 | int err; | |
746 | uint32_t crc; | |
747 | ||
748 | dbg_io("write EC header to PEB %d", pnum); | |
749 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); | |
750 | ||
3261ebd7 | 751 | ec_hdr->magic = cpu_to_be32(UBI_EC_HDR_MAGIC); |
801c135c | 752 | ec_hdr->version = UBI_VERSION; |
3261ebd7 CH |
753 | ec_hdr->vid_hdr_offset = cpu_to_be32(ubi->vid_hdr_offset); |
754 | ec_hdr->data_offset = cpu_to_be32(ubi->leb_start); | |
801c135c | 755 | crc = crc32(UBI_CRC32_INIT, ec_hdr, UBI_EC_HDR_SIZE_CRC); |
3261ebd7 | 756 | ec_hdr->hdr_crc = cpu_to_be32(crc); |
801c135c AB |
757 | |
758 | err = paranoid_check_ec_hdr(ubi, pnum, ec_hdr); | |
759 | if (err) | |
760 | return -EINVAL; | |
761 | ||
762 | err = ubi_io_write(ubi, ec_hdr, pnum, 0, ubi->ec_hdr_alsize); | |
763 | return err; | |
764 | } | |
765 | ||
766 | /** | |
767 | * validate_vid_hdr - validate a volume identifier header. | |
768 | * @ubi: UBI device description object | |
769 | * @vid_hdr: the volume identifier header to check | |
770 | * | |
771 | * This function checks that data stored in the volume identifier header | |
772 | * @vid_hdr. Returns zero if the VID header is OK and %1 if not. | |
773 | */ | |
774 | static int validate_vid_hdr(const struct ubi_device *ubi, | |
775 | const struct ubi_vid_hdr *vid_hdr) | |
776 | { | |
777 | int vol_type = vid_hdr->vol_type; | |
778 | int copy_flag = vid_hdr->copy_flag; | |
3261ebd7 CH |
779 | int vol_id = be32_to_cpu(vid_hdr->vol_id); |
780 | int lnum = be32_to_cpu(vid_hdr->lnum); | |
801c135c | 781 | int compat = vid_hdr->compat; |
3261ebd7 CH |
782 | int data_size = be32_to_cpu(vid_hdr->data_size); |
783 | int used_ebs = be32_to_cpu(vid_hdr->used_ebs); | |
784 | int data_pad = be32_to_cpu(vid_hdr->data_pad); | |
785 | int data_crc = be32_to_cpu(vid_hdr->data_crc); | |
801c135c AB |
786 | int usable_leb_size = ubi->leb_size - data_pad; |
787 | ||
788 | if (copy_flag != 0 && copy_flag != 1) { | |
789 | dbg_err("bad copy_flag"); | |
790 | goto bad; | |
791 | } | |
792 | ||
793 | if (vol_id < 0 || lnum < 0 || data_size < 0 || used_ebs < 0 || | |
794 | data_pad < 0) { | |
795 | dbg_err("negative values"); | |
796 | goto bad; | |
797 | } | |
798 | ||
799 | if (vol_id >= UBI_MAX_VOLUMES && vol_id < UBI_INTERNAL_VOL_START) { | |
800 | dbg_err("bad vol_id"); | |
801 | goto bad; | |
802 | } | |
803 | ||
804 | if (vol_id < UBI_INTERNAL_VOL_START && compat != 0) { | |
805 | dbg_err("bad compat"); | |
806 | goto bad; | |
807 | } | |
808 | ||
809 | if (vol_id >= UBI_INTERNAL_VOL_START && compat != UBI_COMPAT_DELETE && | |
810 | compat != UBI_COMPAT_RO && compat != UBI_COMPAT_PRESERVE && | |
811 | compat != UBI_COMPAT_REJECT) { | |
812 | dbg_err("bad compat"); | |
813 | goto bad; | |
814 | } | |
815 | ||
816 | if (vol_type != UBI_VID_DYNAMIC && vol_type != UBI_VID_STATIC) { | |
817 | dbg_err("bad vol_type"); | |
818 | goto bad; | |
819 | } | |
820 | ||
821 | if (data_pad >= ubi->leb_size / 2) { | |
822 | dbg_err("bad data_pad"); | |
823 | goto bad; | |
824 | } | |
825 | ||
826 | if (vol_type == UBI_VID_STATIC) { | |
827 | /* | |
828 | * Although from high-level point of view static volumes may | |
829 | * contain zero bytes of data, but no VID headers can contain | |
830 | * zero at these fields, because they empty volumes do not have | |
831 | * mapped logical eraseblocks. | |
832 | */ | |
833 | if (used_ebs == 0) { | |
834 | dbg_err("zero used_ebs"); | |
835 | goto bad; | |
836 | } | |
837 | if (data_size == 0) { | |
838 | dbg_err("zero data_size"); | |
839 | goto bad; | |
840 | } | |
841 | if (lnum < used_ebs - 1) { | |
842 | if (data_size != usable_leb_size) { | |
843 | dbg_err("bad data_size"); | |
844 | goto bad; | |
845 | } | |
846 | } else if (lnum == used_ebs - 1) { | |
847 | if (data_size == 0) { | |
848 | dbg_err("bad data_size at last LEB"); | |
849 | goto bad; | |
850 | } | |
851 | } else { | |
852 | dbg_err("too high lnum"); | |
853 | goto bad; | |
854 | } | |
855 | } else { | |
856 | if (copy_flag == 0) { | |
857 | if (data_crc != 0) { | |
858 | dbg_err("non-zero data CRC"); | |
859 | goto bad; | |
860 | } | |
861 | if (data_size != 0) { | |
862 | dbg_err("non-zero data_size"); | |
863 | goto bad; | |
864 | } | |
865 | } else { | |
866 | if (data_size == 0) { | |
867 | dbg_err("zero data_size of copy"); | |
868 | goto bad; | |
869 | } | |
870 | } | |
871 | if (used_ebs != 0) { | |
872 | dbg_err("bad used_ebs"); | |
873 | goto bad; | |
874 | } | |
875 | } | |
876 | ||
877 | return 0; | |
878 | ||
879 | bad: | |
880 | ubi_err("bad VID header"); | |
881 | ubi_dbg_dump_vid_hdr(vid_hdr); | |
882 | ubi_dbg_dump_stack(); | |
883 | return 1; | |
884 | } | |
885 | ||
886 | /** | |
887 | * ubi_io_read_vid_hdr - read and check a volume identifier header. | |
888 | * @ubi: UBI device description object | |
889 | * @pnum: physical eraseblock number to read from | |
890 | * @vid_hdr: &struct ubi_vid_hdr object where to store the read volume | |
891 | * identifier header | |
892 | * @verbose: be verbose if the header is corrupted or wasn't found | |
893 | * | |
894 | * This function reads the volume identifier header from physical eraseblock | |
895 | * @pnum and stores it in @vid_hdr. It also checks CRC checksum of the read | |
896 | * volume identifier header. The following codes may be returned: | |
897 | * | |
898 | * o %0 if the CRC checksum is correct and the header was successfully read; | |
899 | * o %UBI_IO_BITFLIPS if the CRC is correct, but bit-flips were detected | |
900 | * and corrected by the flash driver; this is harmless but may indicate that | |
901 | * this eraseblock may become bad soon; | |
815bc5f8 | 902 | * o %UBI_IO_BAD_VID_HDR if the volume identifier header is corrupted (a CRC |
801c135c AB |
903 | * error detected); |
904 | * o %UBI_IO_PEB_FREE if the physical eraseblock is free (i.e., there is no VID | |
905 | * header there); | |
906 | * o a negative error code in case of failure. | |
907 | */ | |
e88d6e10 | 908 | int ubi_io_read_vid_hdr(struct ubi_device *ubi, int pnum, |
801c135c AB |
909 | struct ubi_vid_hdr *vid_hdr, int verbose) |
910 | { | |
911 | int err, read_err = 0; | |
912 | uint32_t crc, magic, hdr_crc; | |
913 | void *p; | |
914 | ||
915 | dbg_io("read VID header from PEB %d", pnum); | |
916 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); | |
917 | ||
918 | p = (char *)vid_hdr - ubi->vid_hdr_shift; | |
919 | err = ubi_io_read(ubi, p, pnum, ubi->vid_hdr_aloffset, | |
920 | ubi->vid_hdr_alsize); | |
921 | if (err) { | |
922 | if (err != UBI_IO_BITFLIPS && err != -EBADMSG) | |
923 | return err; | |
924 | ||
925 | /* | |
926 | * We read all the data, but either a correctable bit-flip | |
927 | * occurred, or MTD reported about some data integrity error, | |
928 | * like an ECC error in case of NAND. The former is harmless, | |
929 | * the later may mean the read data is corrupted. But we have a | |
930 | * CRC check-sum and we will identify this. If the VID header is | |
931 | * still OK, we just report this as there was a bit-flip. | |
932 | */ | |
933 | read_err = err; | |
934 | } | |
935 | ||
3261ebd7 | 936 | magic = be32_to_cpu(vid_hdr->magic); |
801c135c AB |
937 | if (magic != UBI_VID_HDR_MAGIC) { |
938 | /* | |
939 | * If we have read all 0xFF bytes, the VID header probably does | |
940 | * not exist and the physical eraseblock is assumed to be free. | |
941 | * | |
942 | * But if there was a read error, we do not test the data for | |
943 | * 0xFFs. Even if it does contain all 0xFFs, this error | |
944 | * indicates that something is still wrong with this physical | |
945 | * eraseblock and it cannot be regarded as free. | |
946 | */ | |
947 | if (read_err != -EBADMSG && | |
948 | check_pattern(vid_hdr, 0xFF, UBI_VID_HDR_SIZE)) { | |
949 | /* The physical eraseblock is supposedly free */ | |
950 | ||
951 | /* | |
952 | * The below is just a paranoid check, it has to be | |
953 | * compiled out if paranoid checks are disabled. | |
954 | */ | |
ffb6b7e4 | 955 | err = paranoid_check_empty(ubi, pnum); |
801c135c AB |
956 | if (err) |
957 | return err > 0 ? UBI_IO_BAD_VID_HDR : err; | |
958 | ||
959 | if (verbose) | |
960 | ubi_warn("no VID header found at PEB %d, " | |
961 | "only 0xFF bytes", pnum); | |
ed45819f AB |
962 | else if (UBI_IO_DEBUG) |
963 | dbg_msg("no VID header found at PEB %d, " | |
964 | "only 0xFF bytes", pnum); | |
801c135c AB |
965 | return UBI_IO_PEB_FREE; |
966 | } | |
967 | ||
968 | /* | |
969 | * This is not a valid VID header, and these are not 0xFF | |
970 | * bytes. Report that the header is corrupted. | |
971 | */ | |
972 | if (verbose) { | |
973 | ubi_warn("bad magic number at PEB %d: %08x instead of " | |
974 | "%08x", pnum, magic, UBI_VID_HDR_MAGIC); | |
975 | ubi_dbg_dump_vid_hdr(vid_hdr); | |
ed45819f AB |
976 | } else if (UBI_IO_DEBUG) |
977 | dbg_msg("bad magic number at PEB %d: %08x instead of " | |
978 | "%08x", pnum, magic, UBI_VID_HDR_MAGIC); | |
801c135c AB |
979 | return UBI_IO_BAD_VID_HDR; |
980 | } | |
981 | ||
982 | crc = crc32(UBI_CRC32_INIT, vid_hdr, UBI_VID_HDR_SIZE_CRC); | |
3261ebd7 | 983 | hdr_crc = be32_to_cpu(vid_hdr->hdr_crc); |
801c135c AB |
984 | |
985 | if (hdr_crc != crc) { | |
986 | if (verbose) { | |
987 | ubi_warn("bad CRC at PEB %d, calculated %#08x, " | |
988 | "read %#08x", pnum, crc, hdr_crc); | |
989 | ubi_dbg_dump_vid_hdr(vid_hdr); | |
ed45819f AB |
990 | } else if (UBI_IO_DEBUG) |
991 | dbg_msg("bad CRC at PEB %d, calculated %#08x, " | |
992 | "read %#08x", pnum, crc, hdr_crc); | |
801c135c AB |
993 | return UBI_IO_BAD_VID_HDR; |
994 | } | |
995 | ||
996 | /* Validate the VID header that we have just read */ | |
997 | err = validate_vid_hdr(ubi, vid_hdr); | |
998 | if (err) { | |
999 | ubi_err("validation failed for PEB %d", pnum); | |
1000 | return -EINVAL; | |
1001 | } | |
1002 | ||
1003 | return read_err ? UBI_IO_BITFLIPS : 0; | |
1004 | } | |
1005 | ||
1006 | /** | |
1007 | * ubi_io_write_vid_hdr - write a volume identifier header. | |
1008 | * @ubi: UBI device description object | |
1009 | * @pnum: the physical eraseblock number to write to | |
1010 | * @vid_hdr: the volume identifier header to write | |
1011 | * | |
1012 | * This function writes the volume identifier header described by @vid_hdr to | |
1013 | * physical eraseblock @pnum. This function automatically fills the | |
1014 | * @vid_hdr->magic and the @vid_hdr->version fields, as well as calculates | |
1015 | * header CRC checksum and stores it at vid_hdr->hdr_crc. | |
1016 | * | |
1017 | * This function returns zero in case of success and a negative error code in | |
1018 | * case of failure. If %-EIO is returned, the physical eraseblock probably went | |
1019 | * bad. | |
1020 | */ | |
e88d6e10 | 1021 | int ubi_io_write_vid_hdr(struct ubi_device *ubi, int pnum, |
801c135c AB |
1022 | struct ubi_vid_hdr *vid_hdr) |
1023 | { | |
1024 | int err; | |
1025 | uint32_t crc; | |
1026 | void *p; | |
1027 | ||
1028 | dbg_io("write VID header to PEB %d", pnum); | |
1029 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); | |
1030 | ||
1031 | err = paranoid_check_peb_ec_hdr(ubi, pnum); | |
1032 | if (err) | |
f2863c54 | 1033 | return err > 0 ? -EINVAL : err; |
801c135c | 1034 | |
3261ebd7 | 1035 | vid_hdr->magic = cpu_to_be32(UBI_VID_HDR_MAGIC); |
801c135c AB |
1036 | vid_hdr->version = UBI_VERSION; |
1037 | crc = crc32(UBI_CRC32_INIT, vid_hdr, UBI_VID_HDR_SIZE_CRC); | |
3261ebd7 | 1038 | vid_hdr->hdr_crc = cpu_to_be32(crc); |
801c135c AB |
1039 | |
1040 | err = paranoid_check_vid_hdr(ubi, pnum, vid_hdr); | |
1041 | if (err) | |
1042 | return -EINVAL; | |
1043 | ||
1044 | p = (char *)vid_hdr - ubi->vid_hdr_shift; | |
1045 | err = ubi_io_write(ubi, p, pnum, ubi->vid_hdr_aloffset, | |
1046 | ubi->vid_hdr_alsize); | |
1047 | return err; | |
1048 | } | |
1049 | ||
1050 | #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID | |
1051 | ||
1052 | /** | |
1053 | * paranoid_check_not_bad - ensure that a physical eraseblock is not bad. | |
1054 | * @ubi: UBI device description object | |
1055 | * @pnum: physical eraseblock number to check | |
1056 | * | |
1057 | * This function returns zero if the physical eraseblock is good, a positive | |
1058 | * number if it is bad and a negative error code if an error occurred. | |
1059 | */ | |
1060 | static int paranoid_check_not_bad(const struct ubi_device *ubi, int pnum) | |
1061 | { | |
1062 | int err; | |
1063 | ||
1064 | err = ubi_io_is_bad(ubi, pnum); | |
1065 | if (!err) | |
1066 | return err; | |
1067 | ||
1068 | ubi_err("paranoid check failed for PEB %d", pnum); | |
1069 | ubi_dbg_dump_stack(); | |
1070 | return err; | |
1071 | } | |
1072 | ||
1073 | /** | |
1074 | * paranoid_check_ec_hdr - check if an erase counter header is all right. | |
1075 | * @ubi: UBI device description object | |
1076 | * @pnum: physical eraseblock number the erase counter header belongs to | |
1077 | * @ec_hdr: the erase counter header to check | |
1078 | * | |
1079 | * This function returns zero if the erase counter header contains valid | |
1080 | * values, and %1 if not. | |
1081 | */ | |
1082 | static int paranoid_check_ec_hdr(const struct ubi_device *ubi, int pnum, | |
1083 | const struct ubi_ec_hdr *ec_hdr) | |
1084 | { | |
1085 | int err; | |
1086 | uint32_t magic; | |
1087 | ||
3261ebd7 | 1088 | magic = be32_to_cpu(ec_hdr->magic); |
801c135c AB |
1089 | if (magic != UBI_EC_HDR_MAGIC) { |
1090 | ubi_err("bad magic %#08x, must be %#08x", | |
1091 | magic, UBI_EC_HDR_MAGIC); | |
1092 | goto fail; | |
1093 | } | |
1094 | ||
1095 | err = validate_ec_hdr(ubi, ec_hdr); | |
1096 | if (err) { | |
1097 | ubi_err("paranoid check failed for PEB %d", pnum); | |
1098 | goto fail; | |
1099 | } | |
1100 | ||
1101 | return 0; | |
1102 | ||
1103 | fail: | |
1104 | ubi_dbg_dump_ec_hdr(ec_hdr); | |
1105 | ubi_dbg_dump_stack(); | |
1106 | return 1; | |
1107 | } | |
1108 | ||
1109 | /** | |
ebaaf1af | 1110 | * paranoid_check_peb_ec_hdr - check erase counter header. |
801c135c AB |
1111 | * @ubi: UBI device description object |
1112 | * @pnum: the physical eraseblock number to check | |
1113 | * | |
1114 | * This function returns zero if the erase counter header is all right, %1 if | |
1115 | * not, and a negative error code if an error occurred. | |
1116 | */ | |
1117 | static int paranoid_check_peb_ec_hdr(const struct ubi_device *ubi, int pnum) | |
1118 | { | |
1119 | int err; | |
1120 | uint32_t crc, hdr_crc; | |
1121 | struct ubi_ec_hdr *ec_hdr; | |
1122 | ||
33818bbb | 1123 | ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_NOFS); |
801c135c AB |
1124 | if (!ec_hdr) |
1125 | return -ENOMEM; | |
1126 | ||
1127 | err = ubi_io_read(ubi, ec_hdr, pnum, 0, UBI_EC_HDR_SIZE); | |
1128 | if (err && err != UBI_IO_BITFLIPS && err != -EBADMSG) | |
1129 | goto exit; | |
1130 | ||
1131 | crc = crc32(UBI_CRC32_INIT, ec_hdr, UBI_EC_HDR_SIZE_CRC); | |
3261ebd7 | 1132 | hdr_crc = be32_to_cpu(ec_hdr->hdr_crc); |
801c135c AB |
1133 | if (hdr_crc != crc) { |
1134 | ubi_err("bad CRC, calculated %#08x, read %#08x", crc, hdr_crc); | |
1135 | ubi_err("paranoid check failed for PEB %d", pnum); | |
1136 | ubi_dbg_dump_ec_hdr(ec_hdr); | |
1137 | ubi_dbg_dump_stack(); | |
1138 | err = 1; | |
1139 | goto exit; | |
1140 | } | |
1141 | ||
1142 | err = paranoid_check_ec_hdr(ubi, pnum, ec_hdr); | |
1143 | ||
1144 | exit: | |
1145 | kfree(ec_hdr); | |
1146 | return err; | |
1147 | } | |
1148 | ||
1149 | /** | |
1150 | * paranoid_check_vid_hdr - check that a volume identifier header is all right. | |
1151 | * @ubi: UBI device description object | |
1152 | * @pnum: physical eraseblock number the volume identifier header belongs to | |
1153 | * @vid_hdr: the volume identifier header to check | |
1154 | * | |
1155 | * This function returns zero if the volume identifier header is all right, and | |
1156 | * %1 if not. | |
1157 | */ | |
1158 | static int paranoid_check_vid_hdr(const struct ubi_device *ubi, int pnum, | |
1159 | const struct ubi_vid_hdr *vid_hdr) | |
1160 | { | |
1161 | int err; | |
1162 | uint32_t magic; | |
1163 | ||
3261ebd7 | 1164 | magic = be32_to_cpu(vid_hdr->magic); |
801c135c AB |
1165 | if (magic != UBI_VID_HDR_MAGIC) { |
1166 | ubi_err("bad VID header magic %#08x at PEB %d, must be %#08x", | |
1167 | magic, pnum, UBI_VID_HDR_MAGIC); | |
1168 | goto fail; | |
1169 | } | |
1170 | ||
1171 | err = validate_vid_hdr(ubi, vid_hdr); | |
1172 | if (err) { | |
1173 | ubi_err("paranoid check failed for PEB %d", pnum); | |
1174 | goto fail; | |
1175 | } | |
1176 | ||
1177 | return err; | |
1178 | ||
1179 | fail: | |
1180 | ubi_err("paranoid check failed for PEB %d", pnum); | |
1181 | ubi_dbg_dump_vid_hdr(vid_hdr); | |
1182 | ubi_dbg_dump_stack(); | |
1183 | return 1; | |
1184 | ||
1185 | } | |
1186 | ||
1187 | /** | |
ebaaf1af | 1188 | * paranoid_check_peb_vid_hdr - check volume identifier header. |
801c135c AB |
1189 | * @ubi: UBI device description object |
1190 | * @pnum: the physical eraseblock number to check | |
1191 | * | |
1192 | * This function returns zero if the volume identifier header is all right, | |
1193 | * %1 if not, and a negative error code if an error occurred. | |
1194 | */ | |
1195 | static int paranoid_check_peb_vid_hdr(const struct ubi_device *ubi, int pnum) | |
1196 | { | |
1197 | int err; | |
1198 | uint32_t crc, hdr_crc; | |
1199 | struct ubi_vid_hdr *vid_hdr; | |
1200 | void *p; | |
1201 | ||
33818bbb | 1202 | vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS); |
801c135c AB |
1203 | if (!vid_hdr) |
1204 | return -ENOMEM; | |
1205 | ||
1206 | p = (char *)vid_hdr - ubi->vid_hdr_shift; | |
1207 | err = ubi_io_read(ubi, p, pnum, ubi->vid_hdr_aloffset, | |
1208 | ubi->vid_hdr_alsize); | |
1209 | if (err && err != UBI_IO_BITFLIPS && err != -EBADMSG) | |
1210 | goto exit; | |
1211 | ||
1212 | crc = crc32(UBI_CRC32_INIT, vid_hdr, UBI_EC_HDR_SIZE_CRC); | |
3261ebd7 | 1213 | hdr_crc = be32_to_cpu(vid_hdr->hdr_crc); |
801c135c AB |
1214 | if (hdr_crc != crc) { |
1215 | ubi_err("bad VID header CRC at PEB %d, calculated %#08x, " | |
1216 | "read %#08x", pnum, crc, hdr_crc); | |
1217 | ubi_err("paranoid check failed for PEB %d", pnum); | |
1218 | ubi_dbg_dump_vid_hdr(vid_hdr); | |
1219 | ubi_dbg_dump_stack(); | |
1220 | err = 1; | |
1221 | goto exit; | |
1222 | } | |
1223 | ||
1224 | err = paranoid_check_vid_hdr(ubi, pnum, vid_hdr); | |
1225 | ||
1226 | exit: | |
1227 | ubi_free_vid_hdr(ubi, vid_hdr); | |
1228 | return err; | |
1229 | } | |
1230 | ||
1231 | /** | |
1232 | * paranoid_check_all_ff - check that a region of flash is empty. | |
1233 | * @ubi: UBI device description object | |
1234 | * @pnum: the physical eraseblock number to check | |
1235 | * @offset: the starting offset within the physical eraseblock to check | |
1236 | * @len: the length of the region to check | |
1237 | * | |
1238 | * This function returns zero if only 0xFF bytes are present at offset | |
1239 | * @offset of the physical eraseblock @pnum, %1 if not, and a negative error | |
1240 | * code if an error occurred. | |
1241 | */ | |
e88d6e10 AB |
1242 | static int paranoid_check_all_ff(struct ubi_device *ubi, int pnum, int offset, |
1243 | int len) | |
801c135c AB |
1244 | { |
1245 | size_t read; | |
1246 | int err; | |
801c135c AB |
1247 | loff_t addr = (loff_t)pnum * ubi->peb_size + offset; |
1248 | ||
e88d6e10 AB |
1249 | mutex_lock(&ubi->dbg_buf_mutex); |
1250 | err = ubi->mtd->read(ubi->mtd, addr, len, &read, ubi->dbg_peb_buf); | |
801c135c AB |
1251 | if (err && err != -EUCLEAN) { |
1252 | ubi_err("error %d while reading %d bytes from PEB %d:%d, " | |
1253 | "read %zd bytes", err, len, pnum, offset, read); | |
1254 | goto error; | |
1255 | } | |
1256 | ||
e88d6e10 | 1257 | err = check_pattern(ubi->dbg_peb_buf, 0xFF, len); |
801c135c AB |
1258 | if (err == 0) { |
1259 | ubi_err("flash region at PEB %d:%d, length %d does not " | |
1260 | "contain all 0xFF bytes", pnum, offset, len); | |
1261 | goto fail; | |
1262 | } | |
e88d6e10 | 1263 | mutex_unlock(&ubi->dbg_buf_mutex); |
801c135c | 1264 | |
801c135c AB |
1265 | return 0; |
1266 | ||
1267 | fail: | |
1268 | ubi_err("paranoid check failed for PEB %d", pnum); | |
c8566350 | 1269 | ubi_msg("hex dump of the %d-%d region", offset, offset + len); |
6986646b | 1270 | print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1, |
e88d6e10 | 1271 | ubi->dbg_peb_buf, len, 1); |
801c135c AB |
1272 | err = 1; |
1273 | error: | |
1274 | ubi_dbg_dump_stack(); | |
e88d6e10 | 1275 | mutex_unlock(&ubi->dbg_buf_mutex); |
801c135c AB |
1276 | return err; |
1277 | } | |
1278 | ||
ffb6b7e4 AB |
1279 | /** |
1280 | * paranoid_check_empty - whether a PEB is empty. | |
1281 | * @ubi: UBI device description object | |
1282 | * @pnum: the physical eraseblock number to check | |
1283 | * | |
1284 | * This function makes sure PEB @pnum is empty, which means it contains only | |
1285 | * %0xFF data bytes. Returns zero if the PEB is empty, %1 if not, and a | |
1286 | * negative error code in case of failure. | |
1287 | * | |
1288 | * Empty PEBs have the EC header, and do not have the VID header. The caller of | |
1289 | * this function should have already made sure the PEB does not have the VID | |
1290 | * header. However, this function re-checks that, because it is possible that | |
1291 | * the header and data has already been written to the PEB. | |
1292 | * | |
1293 | * Let's consider a possible scenario. Suppose there are 2 tasks - A and B. | |
1294 | * Task A is in 'wear_leveling_worker()'. It is reading VID header of PEB X to | |
1295 | * find which LEB it corresponds to. PEB X is currently unmapped, and has no | |
1296 | * VID header. Task B is trying to write to PEB X. | |
1297 | * | |
1298 | * Task A: in 'ubi_io_read_vid_hdr()': reads the VID header from PEB X. The | |
1299 | * read data contain all 0xFF bytes; | |
1300 | * Task B: writes VID header and some data to PEB X; | |
1301 | * Task A: assumes PEB X is empty, calls 'paranoid_check_empty()'. And if we | |
1302 | * do not re-read the VID header, and do not cancel the checking if it | |
1303 | * is there, we fail. | |
1304 | */ | |
1305 | static int paranoid_check_empty(struct ubi_device *ubi, int pnum) | |
1306 | { | |
1307 | int err, offs = ubi->vid_hdr_aloffset, len = ubi->vid_hdr_alsize; | |
1308 | size_t read; | |
1309 | uint32_t magic; | |
1310 | const struct ubi_vid_hdr *vid_hdr; | |
1311 | ||
1312 | mutex_lock(&ubi->dbg_buf_mutex); | |
1313 | err = ubi->mtd->read(ubi->mtd, offs, len, &read, ubi->dbg_peb_buf); | |
1314 | if (err && err != -EUCLEAN) { | |
1315 | ubi_err("error %d while reading %d bytes from PEB %d:%d, " | |
1316 | "read %zd bytes", err, len, pnum, offs, read); | |
1317 | goto error; | |
1318 | } | |
1319 | ||
1320 | vid_hdr = ubi->dbg_peb_buf; | |
1321 | magic = be32_to_cpu(vid_hdr->magic); | |
1322 | if (magic == UBI_VID_HDR_MAGIC) | |
1323 | /* The PEB contains VID header, so it is not empty */ | |
1324 | goto out; | |
1325 | ||
1326 | err = check_pattern(ubi->dbg_peb_buf, 0xFF, len); | |
1327 | if (err == 0) { | |
1328 | ubi_err("flash region at PEB %d:%d, length %d does not " | |
1329 | "contain all 0xFF bytes", pnum, offs, len); | |
1330 | goto fail; | |
1331 | } | |
1332 | ||
1333 | out: | |
1334 | mutex_unlock(&ubi->dbg_buf_mutex); | |
1335 | return 0; | |
1336 | ||
1337 | fail: | |
1338 | ubi_err("paranoid check failed for PEB %d", pnum); | |
1339 | ubi_msg("hex dump of the %d-%d region", offs, offs + len); | |
1340 | print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1, | |
1341 | ubi->dbg_peb_buf, len, 1); | |
1342 | err = 1; | |
1343 | error: | |
1344 | ubi_dbg_dump_stack(); | |
1345 | mutex_unlock(&ubi->dbg_buf_mutex); | |
1346 | return err; | |
1347 | } | |
1348 | ||
801c135c | 1349 | #endif /* CONFIG_MTD_UBI_DEBUG_PARANOID */ |