Commit | Line | Data |
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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 | |
be436f62 SK |
67 | * bytes which are not relevant to the sub-page are 0xFF. So, basically, |
68 | * writing 4x512 sub-pages is 4 times slower than writing one 2KiB NAND page. | |
69 | * Thus, we prefer to use sub-pages only for EC and VID headers. | |
801c135c AB |
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> | |
5a0e3ad6 | 91 | #include <linux/slab.h> |
801c135c AB |
92 | #include "ubi.h" |
93 | ||
94 | #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID | |
95 | static int paranoid_check_not_bad(const struct ubi_device *ubi, int pnum); | |
96 | static int paranoid_check_peb_ec_hdr(const struct ubi_device *ubi, int pnum); | |
97 | static int paranoid_check_ec_hdr(const struct ubi_device *ubi, int pnum, | |
98 | const struct ubi_ec_hdr *ec_hdr); | |
99 | static int paranoid_check_peb_vid_hdr(const struct ubi_device *ubi, int pnum); | |
100 | static int paranoid_check_vid_hdr(const struct ubi_device *ubi, int pnum, | |
101 | const struct ubi_vid_hdr *vid_hdr); | |
801c135c AB |
102 | #else |
103 | #define paranoid_check_not_bad(ubi, pnum) 0 | |
104 | #define paranoid_check_peb_ec_hdr(ubi, pnum) 0 | |
105 | #define paranoid_check_ec_hdr(ubi, pnum, ec_hdr) 0 | |
106 | #define paranoid_check_peb_vid_hdr(ubi, pnum) 0 | |
107 | #define paranoid_check_vid_hdr(ubi, pnum, vid_hdr) 0 | |
801c135c AB |
108 | #endif |
109 | ||
110 | /** | |
111 | * ubi_io_read - read data from a physical eraseblock. | |
112 | * @ubi: UBI device description object | |
113 | * @buf: buffer where to store the read data | |
114 | * @pnum: physical eraseblock number to read from | |
115 | * @offset: offset within the physical eraseblock from where to read | |
116 | * @len: how many bytes to read | |
117 | * | |
118 | * This function reads data from offset @offset of physical eraseblock @pnum | |
119 | * and stores the read data in the @buf buffer. The following return codes are | |
120 | * possible: | |
121 | * | |
122 | * o %0 if all the requested data were successfully read; | |
123 | * o %UBI_IO_BITFLIPS if all the requested data were successfully read, but | |
124 | * correctable bit-flips were detected; this is harmless but may indicate | |
125 | * that this eraseblock may become bad soon (but do not have to); | |
63b6c1ed AB |
126 | * o %-EBADMSG if the MTD subsystem reported about data integrity problems, for |
127 | * example it can be an ECC error in case of NAND; this most probably means | |
128 | * that the data is corrupted; | |
801c135c AB |
129 | * o %-EIO if some I/O error occurred; |
130 | * o other negative error codes in case of other errors. | |
131 | */ | |
132 | int ubi_io_read(const struct ubi_device *ubi, void *buf, int pnum, int offset, | |
133 | int len) | |
134 | { | |
135 | int err, retries = 0; | |
136 | size_t read; | |
137 | loff_t addr; | |
138 | ||
139 | dbg_io("read %d bytes from PEB %d:%d", len, pnum, offset); | |
140 | ||
141 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); | |
142 | ubi_assert(offset >= 0 && offset + len <= ubi->peb_size); | |
143 | ubi_assert(len > 0); | |
144 | ||
145 | err = paranoid_check_not_bad(ubi, pnum); | |
146 | if (err) | |
adbf05e3 | 147 | return err; |
801c135c | 148 | |
276832d8 AB |
149 | /* |
150 | * Deliberately corrupt the buffer to improve robustness. Indeed, if we | |
151 | * do not do this, the following may happen: | |
152 | * 1. The buffer contains data from previous operation, e.g., read from | |
153 | * another PEB previously. The data looks like expected, e.g., if we | |
154 | * just do not read anything and return - the caller would not | |
155 | * notice this. E.g., if we are reading a VID header, the buffer may | |
156 | * contain a valid VID header from another PEB. | |
157 | * 2. The driver is buggy and returns us success or -EBADMSG or | |
158 | * -EUCLEAN, but it does not actually put any data to the buffer. | |
159 | * | |
160 | * This may confuse UBI or upper layers - they may think the buffer | |
161 | * contains valid data while in fact it is just old data. This is | |
162 | * especially possible because UBI (and UBIFS) relies on CRC, and | |
163 | * treats data as correct even in case of ECC errors if the CRC is | |
164 | * correct. | |
165 | * | |
166 | * Try to prevent this situation by changing the first byte of the | |
167 | * buffer. | |
168 | */ | |
169 | *((uint8_t *)buf) ^= 0xFF; | |
170 | ||
801c135c AB |
171 | addr = (loff_t)pnum * ubi->peb_size + offset; |
172 | retry: | |
173 | err = ubi->mtd->read(ubi->mtd, addr, len, &read, buf); | |
174 | if (err) { | |
f5d5b1f8 | 175 | const char *errstr = (err == -EBADMSG) ? " (ECC error)" : ""; |
1a49af2c | 176 | |
801c135c AB |
177 | if (err == -EUCLEAN) { |
178 | /* | |
179 | * -EUCLEAN is reported if there was a bit-flip which | |
180 | * was corrected, so this is harmless. | |
8c1e6ee1 AB |
181 | * |
182 | * We do not report about it here unless debugging is | |
183 | * enabled. A corresponding message will be printed | |
184 | * later, when it is has been scrubbed. | |
801c135c | 185 | */ |
8c1e6ee1 | 186 | dbg_msg("fixable bit-flip detected at PEB %d", pnum); |
801c135c AB |
187 | ubi_assert(len == read); |
188 | return UBI_IO_BITFLIPS; | |
189 | } | |
190 | ||
a87f29cb | 191 | if (retries++ < UBI_IO_RETRIES) { |
1a49af2c | 192 | dbg_io("error %d%s while reading %d bytes from PEB %d:%d," |
9c9ec147 | 193 | " read only %zd bytes, retry", |
1a49af2c | 194 | err, errstr, len, pnum, offset, read); |
801c135c AB |
195 | yield(); |
196 | goto retry; | |
197 | } | |
198 | ||
f5d5b1f8 | 199 | ubi_err("error %d%s while reading %d bytes from PEB %d:%d, " |
1a49af2c | 200 | "read %zd bytes", err, errstr, len, pnum, offset, read); |
801c135c | 201 | ubi_dbg_dump_stack(); |
2362a53e AB |
202 | |
203 | /* | |
204 | * The driver should never return -EBADMSG if it failed to read | |
205 | * all the requested data. But some buggy drivers might do | |
206 | * this, so we change it to -EIO. | |
207 | */ | |
208 | if (read != len && err == -EBADMSG) { | |
209 | ubi_assert(0); | |
210 | err = -EIO; | |
211 | } | |
801c135c AB |
212 | } else { |
213 | ubi_assert(len == read); | |
214 | ||
215 | if (ubi_dbg_is_bitflip()) { | |
c8566350 | 216 | dbg_gen("bit-flip (emulated)"); |
801c135c AB |
217 | err = UBI_IO_BITFLIPS; |
218 | } | |
219 | } | |
220 | ||
221 | return err; | |
222 | } | |
223 | ||
224 | /** | |
225 | * ubi_io_write - write data to a physical eraseblock. | |
226 | * @ubi: UBI device description object | |
227 | * @buf: buffer with the data to write | |
228 | * @pnum: physical eraseblock number to write to | |
229 | * @offset: offset within the physical eraseblock where to write | |
230 | * @len: how many bytes to write | |
231 | * | |
232 | * This function writes @len bytes of data from buffer @buf to offset @offset | |
233 | * of physical eraseblock @pnum. If all the data were successfully written, | |
234 | * zero is returned. If an error occurred, this function returns a negative | |
235 | * error code. If %-EIO is returned, the physical eraseblock most probably went | |
236 | * bad. | |
237 | * | |
238 | * Note, in case of an error, it is possible that something was still written | |
239 | * to the flash media, but may be some garbage. | |
240 | */ | |
e88d6e10 AB |
241 | int ubi_io_write(struct ubi_device *ubi, const void *buf, int pnum, int offset, |
242 | int len) | |
801c135c AB |
243 | { |
244 | int err; | |
245 | size_t written; | |
246 | loff_t addr; | |
247 | ||
248 | dbg_io("write %d bytes to PEB %d:%d", len, pnum, offset); | |
249 | ||
250 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); | |
251 | ubi_assert(offset >= 0 && offset + len <= ubi->peb_size); | |
252 | ubi_assert(offset % ubi->hdrs_min_io_size == 0); | |
253 | ubi_assert(len > 0 && len % ubi->hdrs_min_io_size == 0); | |
254 | ||
255 | if (ubi->ro_mode) { | |
256 | ubi_err("read-only mode"); | |
257 | return -EROFS; | |
258 | } | |
259 | ||
260 | /* The below has to be compiled out if paranoid checks are disabled */ | |
261 | ||
262 | err = paranoid_check_not_bad(ubi, pnum); | |
263 | if (err) | |
adbf05e3 | 264 | return err; |
801c135c AB |
265 | |
266 | /* The area we are writing to has to contain all 0xFF bytes */ | |
40a71a87 | 267 | err = ubi_dbg_check_all_ff(ubi, pnum, offset, len); |
801c135c | 268 | if (err) |
adbf05e3 | 269 | return err; |
801c135c AB |
270 | |
271 | if (offset >= ubi->leb_start) { | |
272 | /* | |
273 | * We write to the data area of the physical eraseblock. Make | |
274 | * sure it has valid EC and VID headers. | |
275 | */ | |
276 | err = paranoid_check_peb_ec_hdr(ubi, pnum); | |
277 | if (err) | |
adbf05e3 | 278 | return err; |
801c135c AB |
279 | err = paranoid_check_peb_vid_hdr(ubi, pnum); |
280 | if (err) | |
adbf05e3 | 281 | return err; |
801c135c AB |
282 | } |
283 | ||
284 | if (ubi_dbg_is_write_failure()) { | |
285 | dbg_err("cannot write %d bytes to PEB %d:%d " | |
286 | "(emulated)", len, pnum, offset); | |
287 | ubi_dbg_dump_stack(); | |
288 | return -EIO; | |
289 | } | |
290 | ||
291 | addr = (loff_t)pnum * ubi->peb_size + offset; | |
292 | err = ubi->mtd->write(ubi->mtd, addr, len, &written, buf); | |
293 | if (err) { | |
ebf53f42 AB |
294 | ubi_err("error %d while writing %d bytes to PEB %d:%d, written " |
295 | "%zd bytes", err, len, pnum, offset, written); | |
801c135c | 296 | ubi_dbg_dump_stack(); |
867996b1 | 297 | ubi_dbg_dump_flash(ubi, pnum, offset, len); |
801c135c AB |
298 | } else |
299 | ubi_assert(written == len); | |
300 | ||
6e9065d7 AB |
301 | if (!err) { |
302 | err = ubi_dbg_check_write(ubi, buf, pnum, offset, len); | |
303 | if (err) | |
304 | return err; | |
305 | ||
306 | /* | |
307 | * Since we always write sequentially, the rest of the PEB has | |
308 | * to contain only 0xFF bytes. | |
309 | */ | |
310 | offset += len; | |
311 | len = ubi->peb_size - offset; | |
312 | if (len) | |
313 | err = ubi_dbg_check_all_ff(ubi, pnum, offset, len); | |
314 | } | |
315 | ||
801c135c AB |
316 | return err; |
317 | } | |
318 | ||
319 | /** | |
320 | * erase_callback - MTD erasure call-back. | |
321 | * @ei: MTD erase information object. | |
322 | * | |
323 | * Note, even though MTD erase interface is asynchronous, all the current | |
324 | * implementations are synchronous anyway. | |
325 | */ | |
326 | static void erase_callback(struct erase_info *ei) | |
327 | { | |
328 | wake_up_interruptible((wait_queue_head_t *)ei->priv); | |
329 | } | |
330 | ||
331 | /** | |
332 | * do_sync_erase - synchronously erase a physical eraseblock. | |
333 | * @ubi: UBI device description object | |
334 | * @pnum: the physical eraseblock number to erase | |
335 | * | |
336 | * This function synchronously erases physical eraseblock @pnum and returns | |
337 | * zero in case of success and a negative error code in case of failure. If | |
338 | * %-EIO is returned, the physical eraseblock most probably went bad. | |
339 | */ | |
e88d6e10 | 340 | static int do_sync_erase(struct ubi_device *ubi, int pnum) |
801c135c AB |
341 | { |
342 | int err, retries = 0; | |
343 | struct erase_info ei; | |
344 | wait_queue_head_t wq; | |
345 | ||
346 | dbg_io("erase PEB %d", pnum); | |
347 | ||
348 | retry: | |
349 | init_waitqueue_head(&wq); | |
350 | memset(&ei, 0, sizeof(struct erase_info)); | |
351 | ||
352 | ei.mtd = ubi->mtd; | |
2f176f79 | 353 | ei.addr = (loff_t)pnum * ubi->peb_size; |
801c135c AB |
354 | ei.len = ubi->peb_size; |
355 | ei.callback = erase_callback; | |
356 | ei.priv = (unsigned long)&wq; | |
357 | ||
358 | err = ubi->mtd->erase(ubi->mtd, &ei); | |
359 | if (err) { | |
360 | if (retries++ < UBI_IO_RETRIES) { | |
361 | dbg_io("error %d while erasing PEB %d, retry", | |
362 | err, pnum); | |
363 | yield(); | |
364 | goto retry; | |
365 | } | |
366 | ubi_err("cannot erase PEB %d, error %d", pnum, err); | |
367 | ubi_dbg_dump_stack(); | |
368 | return err; | |
369 | } | |
370 | ||
371 | err = wait_event_interruptible(wq, ei.state == MTD_ERASE_DONE || | |
372 | ei.state == MTD_ERASE_FAILED); | |
373 | if (err) { | |
374 | ubi_err("interrupted PEB %d erasure", pnum); | |
375 | return -EINTR; | |
376 | } | |
377 | ||
378 | if (ei.state == MTD_ERASE_FAILED) { | |
379 | if (retries++ < UBI_IO_RETRIES) { | |
380 | dbg_io("error while erasing PEB %d, retry", pnum); | |
381 | yield(); | |
382 | goto retry; | |
383 | } | |
384 | ubi_err("cannot erase PEB %d", pnum); | |
385 | ubi_dbg_dump_stack(); | |
386 | return -EIO; | |
387 | } | |
388 | ||
40a71a87 | 389 | err = ubi_dbg_check_all_ff(ubi, pnum, 0, ubi->peb_size); |
801c135c | 390 | if (err) |
adbf05e3 | 391 | return err; |
801c135c AB |
392 | |
393 | if (ubi_dbg_is_erase_failure() && !err) { | |
394 | dbg_err("cannot erase PEB %d (emulated)", pnum); | |
395 | return -EIO; | |
396 | } | |
397 | ||
398 | return 0; | |
399 | } | |
400 | ||
801c135c AB |
401 | /* Patterns to write to a physical eraseblock when torturing it */ |
402 | static uint8_t patterns[] = {0xa5, 0x5a, 0x0}; | |
403 | ||
404 | /** | |
405 | * torture_peb - test a supposedly bad physical eraseblock. | |
406 | * @ubi: UBI device description object | |
407 | * @pnum: the physical eraseblock number to test | |
408 | * | |
409 | * This function returns %-EIO if the physical eraseblock did not pass the | |
410 | * test, a positive number of erase operations done if the test was | |
411 | * successfully passed, and other negative error codes in case of other errors. | |
412 | */ | |
e88d6e10 | 413 | static int torture_peb(struct ubi_device *ubi, int pnum) |
801c135c | 414 | { |
801c135c AB |
415 | int err, i, patt_count; |
416 | ||
8c1e6ee1 | 417 | ubi_msg("run torture test for PEB %d", pnum); |
801c135c AB |
418 | patt_count = ARRAY_SIZE(patterns); |
419 | ubi_assert(patt_count > 0); | |
420 | ||
e88d6e10 | 421 | mutex_lock(&ubi->buf_mutex); |
801c135c AB |
422 | for (i = 0; i < patt_count; i++) { |
423 | err = do_sync_erase(ubi, pnum); | |
424 | if (err) | |
425 | goto out; | |
426 | ||
427 | /* Make sure the PEB contains only 0xFF bytes */ | |
e88d6e10 | 428 | err = ubi_io_read(ubi, ubi->peb_buf1, pnum, 0, ubi->peb_size); |
801c135c AB |
429 | if (err) |
430 | goto out; | |
431 | ||
bb00e180 | 432 | err = ubi_check_pattern(ubi->peb_buf1, 0xFF, ubi->peb_size); |
801c135c AB |
433 | if (err == 0) { |
434 | ubi_err("erased PEB %d, but a non-0xFF byte found", | |
435 | pnum); | |
436 | err = -EIO; | |
437 | goto out; | |
438 | } | |
439 | ||
440 | /* Write a pattern and check it */ | |
e88d6e10 AB |
441 | memset(ubi->peb_buf1, patterns[i], ubi->peb_size); |
442 | err = ubi_io_write(ubi, ubi->peb_buf1, pnum, 0, ubi->peb_size); | |
801c135c AB |
443 | if (err) |
444 | goto out; | |
445 | ||
e88d6e10 AB |
446 | memset(ubi->peb_buf1, ~patterns[i], ubi->peb_size); |
447 | err = ubi_io_read(ubi, ubi->peb_buf1, pnum, 0, ubi->peb_size); | |
801c135c AB |
448 | if (err) |
449 | goto out; | |
450 | ||
bb00e180 AB |
451 | err = ubi_check_pattern(ubi->peb_buf1, patterns[i], |
452 | ubi->peb_size); | |
801c135c AB |
453 | if (err == 0) { |
454 | ubi_err("pattern %x checking failed for PEB %d", | |
455 | patterns[i], pnum); | |
456 | err = -EIO; | |
457 | goto out; | |
458 | } | |
459 | } | |
460 | ||
461 | err = patt_count; | |
8c1e6ee1 | 462 | ubi_msg("PEB %d passed torture test, do not mark it a bad", pnum); |
801c135c AB |
463 | |
464 | out: | |
e88d6e10 | 465 | mutex_unlock(&ubi->buf_mutex); |
8d2d4011 | 466 | if (err == UBI_IO_BITFLIPS || err == -EBADMSG) { |
801c135c AB |
467 | /* |
468 | * If a bit-flip or data integrity error was detected, the test | |
469 | * has not passed because it happened on a freshly erased | |
470 | * physical eraseblock which means something is wrong with it. | |
471 | */ | |
8d2d4011 AB |
472 | ubi_err("read problems on freshly erased PEB %d, must be bad", |
473 | pnum); | |
801c135c | 474 | err = -EIO; |
8d2d4011 | 475 | } |
801c135c AB |
476 | return err; |
477 | } | |
478 | ||
ebf53f42 AB |
479 | /** |
480 | * nor_erase_prepare - prepare a NOR flash PEB for erasure. | |
481 | * @ubi: UBI device description object | |
482 | * @pnum: physical eraseblock number to prepare | |
483 | * | |
484 | * NOR flash, or at least some of them, have peculiar embedded PEB erasure | |
485 | * algorithm: the PEB is first filled with zeroes, then it is erased. And | |
486 | * filling with zeroes starts from the end of the PEB. This was observed with | |
487 | * Spansion S29GL512N NOR flash. | |
488 | * | |
489 | * This means that in case of a power cut we may end up with intact data at the | |
490 | * beginning of the PEB, and all zeroes at the end of PEB. In other words, the | |
491 | * EC and VID headers are OK, but a large chunk of data at the end of PEB is | |
492 | * zeroed. This makes UBI mistakenly treat this PEB as used and associate it | |
493 | * with an LEB, which leads to subsequent failures (e.g., UBIFS fails). | |
494 | * | |
495 | * This function is called before erasing NOR PEBs and it zeroes out EC and VID | |
496 | * magic numbers in order to invalidate them and prevent the failures. Returns | |
497 | * zero in case of success and a negative error code in case of failure. | |
498 | */ | |
499 | static int nor_erase_prepare(struct ubi_device *ubi, int pnum) | |
500 | { | |
de75c771 | 501 | int err, err1; |
ebf53f42 AB |
502 | size_t written; |
503 | loff_t addr; | |
504 | uint32_t data = 0; | |
2fff570e AB |
505 | /* |
506 | * Note, we cannot generally define VID header buffers on stack, | |
507 | * because of the way we deal with these buffers (see the header | |
508 | * comment in this file). But we know this is a NOR-specific piece of | |
509 | * code, so we can do this. But yes, this is error-prone and we should | |
510 | * (pre-)allocate VID header buffer instead. | |
511 | */ | |
de75c771 | 512 | struct ubi_vid_hdr vid_hdr; |
ebf53f42 | 513 | |
7ac760c2 AB |
514 | /* |
515 | * It is important to first invalidate the EC header, and then the VID | |
516 | * header. Otherwise a power cut may lead to valid EC header and | |
517 | * invalid VID header, in which case UBI will treat this PEB as | |
518 | * corrupted and will try to preserve it, and print scary warnings (see | |
519 | * the header comment in scan.c for more information). | |
520 | */ | |
521 | addr = (loff_t)pnum * ubi->peb_size; | |
83c2099f | 522 | err = ubi->mtd->write(ubi->mtd, addr, 4, &written, (void *)&data); |
de75c771 | 523 | if (!err) { |
7ac760c2 | 524 | addr += ubi->vid_hdr_aloffset; |
de75c771 AB |
525 | err = ubi->mtd->write(ubi->mtd, addr, 4, &written, |
526 | (void *)&data); | |
527 | if (!err) | |
528 | return 0; | |
ebf53f42 AB |
529 | } |
530 | ||
de75c771 AB |
531 | /* |
532 | * We failed to write to the media. This was observed with Spansion | |
7ac760c2 AB |
533 | * S29GL512N NOR flash. Most probably the previously eraseblock erasure |
534 | * was interrupted at a very inappropriate moment, so it became | |
535 | * unwritable. In this case we probably anyway have garbage in this | |
536 | * PEB. | |
de75c771 AB |
537 | */ |
538 | err1 = ubi_io_read_vid_hdr(ubi, pnum, &vid_hdr, 0); | |
d4c63813 HB |
539 | if (err1 == UBI_IO_BAD_HDR_EBADMSG || err1 == UBI_IO_BAD_HDR || |
540 | err1 == UBI_IO_FF) { | |
7ac760c2 AB |
541 | struct ubi_ec_hdr ec_hdr; |
542 | ||
543 | err1 = ubi_io_read_ec_hdr(ubi, pnum, &ec_hdr, 0); | |
d4c63813 HB |
544 | if (err1 == UBI_IO_BAD_HDR_EBADMSG || err1 == UBI_IO_BAD_HDR || |
545 | err1 == UBI_IO_FF) | |
7ac760c2 AB |
546 | /* |
547 | * Both VID and EC headers are corrupted, so we can | |
548 | * safely erase this PEB and not afraid that it will be | |
549 | * treated as a valid PEB in case of an unclean reboot. | |
550 | */ | |
551 | return 0; | |
552 | } | |
de75c771 AB |
553 | |
554 | /* | |
555 | * The PEB contains a valid VID header, but we cannot invalidate it. | |
556 | * Supposedly the flash media or the driver is screwed up, so return an | |
557 | * error. | |
558 | */ | |
559 | ubi_err("cannot invalidate PEB %d, write returned %d read returned %d", | |
560 | pnum, err, err1); | |
561 | ubi_dbg_dump_flash(ubi, pnum, 0, ubi->peb_size); | |
562 | return -EIO; | |
ebf53f42 AB |
563 | } |
564 | ||
801c135c AB |
565 | /** |
566 | * ubi_io_sync_erase - synchronously erase a physical eraseblock. | |
567 | * @ubi: UBI device description object | |
568 | * @pnum: physical eraseblock number to erase | |
569 | * @torture: if this physical eraseblock has to be tortured | |
570 | * | |
571 | * This function synchronously erases physical eraseblock @pnum. If @torture | |
572 | * flag is not zero, the physical eraseblock is checked by means of writing | |
573 | * different patterns to it and reading them back. If the torturing is enabled, | |
025dfdaf | 574 | * the physical eraseblock is erased more than once. |
801c135c AB |
575 | * |
576 | * This function returns the number of erasures made in case of success, %-EIO | |
577 | * if the erasure failed or the torturing test failed, and other negative error | |
578 | * codes in case of other errors. Note, %-EIO means that the physical | |
579 | * eraseblock is bad. | |
580 | */ | |
e88d6e10 | 581 | int ubi_io_sync_erase(struct ubi_device *ubi, int pnum, int torture) |
801c135c AB |
582 | { |
583 | int err, ret = 0; | |
584 | ||
585 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); | |
586 | ||
587 | err = paranoid_check_not_bad(ubi, pnum); | |
588 | if (err != 0) | |
adbf05e3 | 589 | return err; |
801c135c AB |
590 | |
591 | if (ubi->ro_mode) { | |
592 | ubi_err("read-only mode"); | |
593 | return -EROFS; | |
594 | } | |
595 | ||
ebf53f42 AB |
596 | if (ubi->nor_flash) { |
597 | err = nor_erase_prepare(ubi, pnum); | |
598 | if (err) | |
599 | return err; | |
600 | } | |
601 | ||
801c135c AB |
602 | if (torture) { |
603 | ret = torture_peb(ubi, pnum); | |
604 | if (ret < 0) | |
605 | return ret; | |
606 | } | |
607 | ||
608 | err = do_sync_erase(ubi, pnum); | |
609 | if (err) | |
610 | return err; | |
611 | ||
612 | return ret + 1; | |
613 | } | |
614 | ||
615 | /** | |
616 | * ubi_io_is_bad - check if a physical eraseblock is bad. | |
617 | * @ubi: UBI device description object | |
618 | * @pnum: the physical eraseblock number to check | |
619 | * | |
620 | * This function returns a positive number if the physical eraseblock is bad, | |
621 | * zero if not, and a negative error code if an error occurred. | |
622 | */ | |
623 | int ubi_io_is_bad(const struct ubi_device *ubi, int pnum) | |
624 | { | |
625 | struct mtd_info *mtd = ubi->mtd; | |
626 | ||
627 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); | |
628 | ||
629 | if (ubi->bad_allowed) { | |
630 | int ret; | |
631 | ||
632 | ret = mtd->block_isbad(mtd, (loff_t)pnum * ubi->peb_size); | |
633 | if (ret < 0) | |
634 | ubi_err("error %d while checking if PEB %d is bad", | |
635 | ret, pnum); | |
636 | else if (ret) | |
637 | dbg_io("PEB %d is bad", pnum); | |
638 | return ret; | |
639 | } | |
640 | ||
641 | return 0; | |
642 | } | |
643 | ||
644 | /** | |
645 | * ubi_io_mark_bad - mark a physical eraseblock as bad. | |
646 | * @ubi: UBI device description object | |
647 | * @pnum: the physical eraseblock number to mark | |
648 | * | |
649 | * This function returns zero in case of success and a negative error code in | |
650 | * case of failure. | |
651 | */ | |
652 | int ubi_io_mark_bad(const struct ubi_device *ubi, int pnum) | |
653 | { | |
654 | int err; | |
655 | struct mtd_info *mtd = ubi->mtd; | |
656 | ||
657 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); | |
658 | ||
659 | if (ubi->ro_mode) { | |
660 | ubi_err("read-only mode"); | |
661 | return -EROFS; | |
662 | } | |
663 | ||
664 | if (!ubi->bad_allowed) | |
665 | return 0; | |
666 | ||
667 | err = mtd->block_markbad(mtd, (loff_t)pnum * ubi->peb_size); | |
668 | if (err) | |
669 | ubi_err("cannot mark PEB %d bad, error %d", pnum, err); | |
670 | return err; | |
671 | } | |
672 | ||
673 | /** | |
674 | * validate_ec_hdr - validate an erase counter header. | |
675 | * @ubi: UBI device description object | |
676 | * @ec_hdr: the erase counter header to check | |
677 | * | |
678 | * This function returns zero if the erase counter header is OK, and %1 if | |
679 | * not. | |
680 | */ | |
fe96efc1 | 681 | static int validate_ec_hdr(const struct ubi_device *ubi, |
801c135c AB |
682 | const struct ubi_ec_hdr *ec_hdr) |
683 | { | |
684 | long long ec; | |
fe96efc1 | 685 | int vid_hdr_offset, leb_start; |
801c135c | 686 | |
3261ebd7 CH |
687 | ec = be64_to_cpu(ec_hdr->ec); |
688 | vid_hdr_offset = be32_to_cpu(ec_hdr->vid_hdr_offset); | |
689 | leb_start = be32_to_cpu(ec_hdr->data_offset); | |
801c135c AB |
690 | |
691 | if (ec_hdr->version != UBI_VERSION) { | |
692 | ubi_err("node with incompatible UBI version found: " | |
693 | "this UBI version is %d, image version is %d", | |
694 | UBI_VERSION, (int)ec_hdr->version); | |
695 | goto bad; | |
696 | } | |
697 | ||
698 | if (vid_hdr_offset != ubi->vid_hdr_offset) { | |
699 | ubi_err("bad VID header offset %d, expected %d", | |
700 | vid_hdr_offset, ubi->vid_hdr_offset); | |
701 | goto bad; | |
702 | } | |
703 | ||
704 | if (leb_start != ubi->leb_start) { | |
705 | ubi_err("bad data offset %d, expected %d", | |
706 | leb_start, ubi->leb_start); | |
707 | goto bad; | |
708 | } | |
709 | ||
710 | if (ec < 0 || ec > UBI_MAX_ERASECOUNTER) { | |
711 | ubi_err("bad erase counter %lld", ec); | |
712 | goto bad; | |
713 | } | |
714 | ||
715 | return 0; | |
716 | ||
717 | bad: | |
718 | ubi_err("bad EC header"); | |
719 | ubi_dbg_dump_ec_hdr(ec_hdr); | |
720 | ubi_dbg_dump_stack(); | |
721 | return 1; | |
722 | } | |
723 | ||
724 | /** | |
725 | * ubi_io_read_ec_hdr - read and check an erase counter header. | |
726 | * @ubi: UBI device description object | |
727 | * @pnum: physical eraseblock to read from | |
728 | * @ec_hdr: a &struct ubi_ec_hdr object where to store the read erase counter | |
729 | * header | |
730 | * @verbose: be verbose if the header is corrupted or was not found | |
731 | * | |
732 | * This function reads erase counter header from physical eraseblock @pnum and | |
733 | * stores it in @ec_hdr. This function also checks CRC checksum of the read | |
734 | * erase counter header. The following codes may be returned: | |
735 | * | |
736 | * o %0 if the CRC checksum is correct and the header was successfully read; | |
737 | * o %UBI_IO_BITFLIPS if the CRC is correct, but bit-flips were detected | |
738 | * and corrected by the flash driver; this is harmless but may indicate that | |
739 | * this eraseblock may become bad soon (but may be not); | |
786d7831 | 740 | * o %UBI_IO_BAD_HDR if the erase counter header is corrupted (a CRC error); |
756e1df1 AB |
741 | * o %UBI_IO_BAD_HDR_EBADMSG is the same as %UBI_IO_BAD_HDR, but there also was |
742 | * a data integrity error (uncorrectable ECC error in case of NAND); | |
74d82d26 | 743 | * o %UBI_IO_FF if only 0xFF bytes were read (the PEB is supposedly empty) |
801c135c AB |
744 | * o a negative error code in case of failure. |
745 | */ | |
e88d6e10 | 746 | int ubi_io_read_ec_hdr(struct ubi_device *ubi, int pnum, |
801c135c AB |
747 | struct ubi_ec_hdr *ec_hdr, int verbose) |
748 | { | |
92e1a7d9 | 749 | int err, read_err; |
801c135c AB |
750 | uint32_t crc, magic, hdr_crc; |
751 | ||
752 | dbg_io("read EC header from PEB %d", pnum); | |
753 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); | |
754 | ||
92e1a7d9 AB |
755 | read_err = ubi_io_read(ubi, ec_hdr, pnum, 0, UBI_EC_HDR_SIZE); |
756 | if (read_err) { | |
757 | if (read_err != UBI_IO_BITFLIPS && read_err != -EBADMSG) | |
758 | return read_err; | |
801c135c AB |
759 | |
760 | /* | |
761 | * We read all the data, but either a correctable bit-flip | |
756e1df1 AB |
762 | * occurred, or MTD reported a data integrity error |
763 | * (uncorrectable ECC error in case of NAND). The former is | |
764 | * harmless, the later may mean that the read data is | |
765 | * corrupted. But we have a CRC check-sum and we will detect | |
766 | * this. If the EC header is still OK, we just report this as | |
767 | * there was a bit-flip, to force scrubbing. | |
801c135c | 768 | */ |
801c135c AB |
769 | } |
770 | ||
3261ebd7 | 771 | magic = be32_to_cpu(ec_hdr->magic); |
801c135c | 772 | if (magic != UBI_EC_HDR_MAGIC) { |
92e1a7d9 AB |
773 | if (read_err == -EBADMSG) |
774 | return UBI_IO_BAD_HDR_EBADMSG; | |
eb89580e | 775 | |
801c135c AB |
776 | /* |
777 | * The magic field is wrong. Let's check if we have read all | |
778 | * 0xFF. If yes, this physical eraseblock is assumed to be | |
779 | * empty. | |
801c135c | 780 | */ |
bb00e180 | 781 | if (ubi_check_pattern(ec_hdr, 0xFF, UBI_EC_HDR_SIZE)) { |
801c135c | 782 | /* The physical eraseblock is supposedly empty */ |
801c135c AB |
783 | if (verbose) |
784 | ubi_warn("no EC header found at PEB %d, " | |
785 | "only 0xFF bytes", pnum); | |
ed45819f AB |
786 | else if (UBI_IO_DEBUG) |
787 | dbg_msg("no EC header found at PEB %d, " | |
788 | "only 0xFF bytes", pnum); | |
92e1a7d9 AB |
789 | if (!read_err) |
790 | return UBI_IO_FF; | |
791 | else | |
792 | return UBI_IO_FF_BITFLIPS; | |
801c135c AB |
793 | } |
794 | ||
795 | /* | |
796 | * This is not a valid erase counter header, and these are not | |
797 | * 0xFF bytes. Report that the header is corrupted. | |
798 | */ | |
799 | if (verbose) { | |
800 | ubi_warn("bad magic number at PEB %d: %08x instead of " | |
801 | "%08x", pnum, magic, UBI_EC_HDR_MAGIC); | |
802 | ubi_dbg_dump_ec_hdr(ec_hdr); | |
ed45819f AB |
803 | } else if (UBI_IO_DEBUG) |
804 | dbg_msg("bad magic number at PEB %d: %08x instead of " | |
805 | "%08x", pnum, magic, UBI_EC_HDR_MAGIC); | |
786d7831 | 806 | return UBI_IO_BAD_HDR; |
801c135c AB |
807 | } |
808 | ||
809 | crc = crc32(UBI_CRC32_INIT, ec_hdr, UBI_EC_HDR_SIZE_CRC); | |
3261ebd7 | 810 | hdr_crc = be32_to_cpu(ec_hdr->hdr_crc); |
801c135c AB |
811 | |
812 | if (hdr_crc != crc) { | |
813 | if (verbose) { | |
9c9ec147 AB |
814 | ubi_warn("bad EC header CRC at PEB %d, calculated " |
815 | "%#08x, read %#08x", pnum, crc, hdr_crc); | |
801c135c | 816 | ubi_dbg_dump_ec_hdr(ec_hdr); |
ed45819f AB |
817 | } else if (UBI_IO_DEBUG) |
818 | dbg_msg("bad EC header CRC at PEB %d, calculated " | |
819 | "%#08x, read %#08x", pnum, crc, hdr_crc); | |
92e1a7d9 AB |
820 | |
821 | if (!read_err) | |
822 | return UBI_IO_BAD_HDR; | |
823 | else | |
824 | return UBI_IO_BAD_HDR_EBADMSG; | |
801c135c AB |
825 | } |
826 | ||
827 | /* And of course validate what has just been read from the media */ | |
828 | err = validate_ec_hdr(ubi, ec_hdr); | |
829 | if (err) { | |
830 | ubi_err("validation failed for PEB %d", pnum); | |
831 | return -EINVAL; | |
832 | } | |
833 | ||
eb89580e AB |
834 | /* |
835 | * If there was %-EBADMSG, but the header CRC is still OK, report about | |
836 | * a bit-flip to force scrubbing on this PEB. | |
837 | */ | |
801c135c AB |
838 | return read_err ? UBI_IO_BITFLIPS : 0; |
839 | } | |
840 | ||
841 | /** | |
842 | * ubi_io_write_ec_hdr - write an erase counter header. | |
843 | * @ubi: UBI device description object | |
844 | * @pnum: physical eraseblock to write to | |
845 | * @ec_hdr: the erase counter header to write | |
846 | * | |
847 | * This function writes erase counter header described by @ec_hdr to physical | |
848 | * eraseblock @pnum. It also fills most fields of @ec_hdr before writing, so | |
849 | * the caller do not have to fill them. Callers must only fill the @ec_hdr->ec | |
850 | * field. | |
851 | * | |
852 | * This function returns zero in case of success and a negative error code in | |
853 | * case of failure. If %-EIO is returned, the physical eraseblock most probably | |
854 | * went bad. | |
855 | */ | |
e88d6e10 | 856 | int ubi_io_write_ec_hdr(struct ubi_device *ubi, int pnum, |
801c135c AB |
857 | struct ubi_ec_hdr *ec_hdr) |
858 | { | |
859 | int err; | |
860 | uint32_t crc; | |
861 | ||
862 | dbg_io("write EC header to PEB %d", pnum); | |
863 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); | |
864 | ||
3261ebd7 | 865 | ec_hdr->magic = cpu_to_be32(UBI_EC_HDR_MAGIC); |
801c135c | 866 | ec_hdr->version = UBI_VERSION; |
3261ebd7 CH |
867 | ec_hdr->vid_hdr_offset = cpu_to_be32(ubi->vid_hdr_offset); |
868 | ec_hdr->data_offset = cpu_to_be32(ubi->leb_start); | |
0c6c7fa1 | 869 | ec_hdr->image_seq = cpu_to_be32(ubi->image_seq); |
801c135c | 870 | crc = crc32(UBI_CRC32_INIT, ec_hdr, UBI_EC_HDR_SIZE_CRC); |
3261ebd7 | 871 | ec_hdr->hdr_crc = cpu_to_be32(crc); |
801c135c AB |
872 | |
873 | err = paranoid_check_ec_hdr(ubi, pnum, ec_hdr); | |
874 | if (err) | |
adbf05e3 | 875 | return err; |
801c135c AB |
876 | |
877 | err = ubi_io_write(ubi, ec_hdr, pnum, 0, ubi->ec_hdr_alsize); | |
878 | return err; | |
879 | } | |
880 | ||
881 | /** | |
882 | * validate_vid_hdr - validate a volume identifier header. | |
883 | * @ubi: UBI device description object | |
884 | * @vid_hdr: the volume identifier header to check | |
885 | * | |
886 | * This function checks that data stored in the volume identifier header | |
887 | * @vid_hdr. Returns zero if the VID header is OK and %1 if not. | |
888 | */ | |
889 | static int validate_vid_hdr(const struct ubi_device *ubi, | |
890 | const struct ubi_vid_hdr *vid_hdr) | |
891 | { | |
892 | int vol_type = vid_hdr->vol_type; | |
893 | int copy_flag = vid_hdr->copy_flag; | |
3261ebd7 CH |
894 | int vol_id = be32_to_cpu(vid_hdr->vol_id); |
895 | int lnum = be32_to_cpu(vid_hdr->lnum); | |
801c135c | 896 | int compat = vid_hdr->compat; |
3261ebd7 CH |
897 | int data_size = be32_to_cpu(vid_hdr->data_size); |
898 | int used_ebs = be32_to_cpu(vid_hdr->used_ebs); | |
899 | int data_pad = be32_to_cpu(vid_hdr->data_pad); | |
900 | int data_crc = be32_to_cpu(vid_hdr->data_crc); | |
801c135c AB |
901 | int usable_leb_size = ubi->leb_size - data_pad; |
902 | ||
903 | if (copy_flag != 0 && copy_flag != 1) { | |
904 | dbg_err("bad copy_flag"); | |
905 | goto bad; | |
906 | } | |
907 | ||
908 | if (vol_id < 0 || lnum < 0 || data_size < 0 || used_ebs < 0 || | |
909 | data_pad < 0) { | |
910 | dbg_err("negative values"); | |
911 | goto bad; | |
912 | } | |
913 | ||
914 | if (vol_id >= UBI_MAX_VOLUMES && vol_id < UBI_INTERNAL_VOL_START) { | |
915 | dbg_err("bad vol_id"); | |
916 | goto bad; | |
917 | } | |
918 | ||
919 | if (vol_id < UBI_INTERNAL_VOL_START && compat != 0) { | |
920 | dbg_err("bad compat"); | |
921 | goto bad; | |
922 | } | |
923 | ||
924 | if (vol_id >= UBI_INTERNAL_VOL_START && compat != UBI_COMPAT_DELETE && | |
925 | compat != UBI_COMPAT_RO && compat != UBI_COMPAT_PRESERVE && | |
926 | compat != UBI_COMPAT_REJECT) { | |
927 | dbg_err("bad compat"); | |
928 | goto bad; | |
929 | } | |
930 | ||
931 | if (vol_type != UBI_VID_DYNAMIC && vol_type != UBI_VID_STATIC) { | |
932 | dbg_err("bad vol_type"); | |
933 | goto bad; | |
934 | } | |
935 | ||
936 | if (data_pad >= ubi->leb_size / 2) { | |
937 | dbg_err("bad data_pad"); | |
938 | goto bad; | |
939 | } | |
940 | ||
941 | if (vol_type == UBI_VID_STATIC) { | |
942 | /* | |
943 | * Although from high-level point of view static volumes may | |
944 | * contain zero bytes of data, but no VID headers can contain | |
945 | * zero at these fields, because they empty volumes do not have | |
946 | * mapped logical eraseblocks. | |
947 | */ | |
948 | if (used_ebs == 0) { | |
949 | dbg_err("zero used_ebs"); | |
950 | goto bad; | |
951 | } | |
952 | if (data_size == 0) { | |
953 | dbg_err("zero data_size"); | |
954 | goto bad; | |
955 | } | |
956 | if (lnum < used_ebs - 1) { | |
957 | if (data_size != usable_leb_size) { | |
958 | dbg_err("bad data_size"); | |
959 | goto bad; | |
960 | } | |
961 | } else if (lnum == used_ebs - 1) { | |
962 | if (data_size == 0) { | |
963 | dbg_err("bad data_size at last LEB"); | |
964 | goto bad; | |
965 | } | |
966 | } else { | |
967 | dbg_err("too high lnum"); | |
968 | goto bad; | |
969 | } | |
970 | } else { | |
971 | if (copy_flag == 0) { | |
972 | if (data_crc != 0) { | |
973 | dbg_err("non-zero data CRC"); | |
974 | goto bad; | |
975 | } | |
976 | if (data_size != 0) { | |
977 | dbg_err("non-zero data_size"); | |
978 | goto bad; | |
979 | } | |
980 | } else { | |
981 | if (data_size == 0) { | |
982 | dbg_err("zero data_size of copy"); | |
983 | goto bad; | |
984 | } | |
985 | } | |
986 | if (used_ebs != 0) { | |
987 | dbg_err("bad used_ebs"); | |
988 | goto bad; | |
989 | } | |
990 | } | |
991 | ||
992 | return 0; | |
993 | ||
994 | bad: | |
995 | ubi_err("bad VID header"); | |
996 | ubi_dbg_dump_vid_hdr(vid_hdr); | |
997 | ubi_dbg_dump_stack(); | |
998 | return 1; | |
999 | } | |
1000 | ||
1001 | /** | |
1002 | * ubi_io_read_vid_hdr - read and check a volume identifier header. | |
1003 | * @ubi: UBI device description object | |
1004 | * @pnum: physical eraseblock number to read from | |
1005 | * @vid_hdr: &struct ubi_vid_hdr object where to store the read volume | |
1006 | * identifier header | |
1007 | * @verbose: be verbose if the header is corrupted or wasn't found | |
1008 | * | |
1009 | * This function reads the volume identifier header from physical eraseblock | |
1010 | * @pnum and stores it in @vid_hdr. It also checks CRC checksum of the read | |
74d82d26 AB |
1011 | * volume identifier header. The error codes are the same as in |
1012 | * 'ubi_io_read_ec_hdr()'. | |
801c135c | 1013 | * |
74d82d26 AB |
1014 | * Note, the implementation of this function is also very similar to |
1015 | * 'ubi_io_read_ec_hdr()', so refer commentaries in 'ubi_io_read_ec_hdr()'. | |
801c135c | 1016 | */ |
e88d6e10 | 1017 | int ubi_io_read_vid_hdr(struct ubi_device *ubi, int pnum, |
801c135c AB |
1018 | struct ubi_vid_hdr *vid_hdr, int verbose) |
1019 | { | |
92e1a7d9 | 1020 | int err, read_err; |
801c135c AB |
1021 | uint32_t crc, magic, hdr_crc; |
1022 | void *p; | |
1023 | ||
1024 | dbg_io("read VID header from PEB %d", pnum); | |
1025 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); | |
1026 | ||
1027 | p = (char *)vid_hdr - ubi->vid_hdr_shift; | |
92e1a7d9 | 1028 | read_err = ubi_io_read(ubi, p, pnum, ubi->vid_hdr_aloffset, |
801c135c | 1029 | ubi->vid_hdr_alsize); |
92e1a7d9 AB |
1030 | if (read_err && read_err != UBI_IO_BITFLIPS && read_err != -EBADMSG) |
1031 | return read_err; | |
801c135c | 1032 | |
3261ebd7 | 1033 | magic = be32_to_cpu(vid_hdr->magic); |
801c135c | 1034 | if (magic != UBI_VID_HDR_MAGIC) { |
92e1a7d9 AB |
1035 | if (read_err == -EBADMSG) |
1036 | return UBI_IO_BAD_HDR_EBADMSG; | |
eb89580e | 1037 | |
bb00e180 | 1038 | if (ubi_check_pattern(vid_hdr, 0xFF, UBI_VID_HDR_SIZE)) { |
801c135c AB |
1039 | if (verbose) |
1040 | ubi_warn("no VID header found at PEB %d, " | |
1041 | "only 0xFF bytes", pnum); | |
ed45819f AB |
1042 | else if (UBI_IO_DEBUG) |
1043 | dbg_msg("no VID header found at PEB %d, " | |
1044 | "only 0xFF bytes", pnum); | |
92e1a7d9 AB |
1045 | if (!read_err) |
1046 | return UBI_IO_FF; | |
1047 | else | |
1048 | return UBI_IO_FF_BITFLIPS; | |
801c135c AB |
1049 | } |
1050 | ||
801c135c AB |
1051 | if (verbose) { |
1052 | ubi_warn("bad magic number at PEB %d: %08x instead of " | |
1053 | "%08x", pnum, magic, UBI_VID_HDR_MAGIC); | |
1054 | ubi_dbg_dump_vid_hdr(vid_hdr); | |
ed45819f AB |
1055 | } else if (UBI_IO_DEBUG) |
1056 | dbg_msg("bad magic number at PEB %d: %08x instead of " | |
1057 | "%08x", pnum, magic, UBI_VID_HDR_MAGIC); | |
786d7831 | 1058 | return UBI_IO_BAD_HDR; |
801c135c AB |
1059 | } |
1060 | ||
1061 | crc = crc32(UBI_CRC32_INIT, vid_hdr, UBI_VID_HDR_SIZE_CRC); | |
3261ebd7 | 1062 | hdr_crc = be32_to_cpu(vid_hdr->hdr_crc); |
801c135c AB |
1063 | |
1064 | if (hdr_crc != crc) { | |
1065 | if (verbose) { | |
1066 | ubi_warn("bad CRC at PEB %d, calculated %#08x, " | |
1067 | "read %#08x", pnum, crc, hdr_crc); | |
1068 | ubi_dbg_dump_vid_hdr(vid_hdr); | |
ed45819f AB |
1069 | } else if (UBI_IO_DEBUG) |
1070 | dbg_msg("bad CRC at PEB %d, calculated %#08x, " | |
1071 | "read %#08x", pnum, crc, hdr_crc); | |
92e1a7d9 AB |
1072 | if (!read_err) |
1073 | return UBI_IO_BAD_HDR; | |
1074 | else | |
1075 | return UBI_IO_BAD_HDR_EBADMSG; | |
801c135c AB |
1076 | } |
1077 | ||
801c135c AB |
1078 | err = validate_vid_hdr(ubi, vid_hdr); |
1079 | if (err) { | |
1080 | ubi_err("validation failed for PEB %d", pnum); | |
1081 | return -EINVAL; | |
1082 | } | |
1083 | ||
1084 | return read_err ? UBI_IO_BITFLIPS : 0; | |
1085 | } | |
1086 | ||
1087 | /** | |
1088 | * ubi_io_write_vid_hdr - write a volume identifier header. | |
1089 | * @ubi: UBI device description object | |
1090 | * @pnum: the physical eraseblock number to write to | |
1091 | * @vid_hdr: the volume identifier header to write | |
1092 | * | |
1093 | * This function writes the volume identifier header described by @vid_hdr to | |
1094 | * physical eraseblock @pnum. This function automatically fills the | |
1095 | * @vid_hdr->magic and the @vid_hdr->version fields, as well as calculates | |
1096 | * header CRC checksum and stores it at vid_hdr->hdr_crc. | |
1097 | * | |
1098 | * This function returns zero in case of success and a negative error code in | |
1099 | * case of failure. If %-EIO is returned, the physical eraseblock probably went | |
1100 | * bad. | |
1101 | */ | |
e88d6e10 | 1102 | int ubi_io_write_vid_hdr(struct ubi_device *ubi, int pnum, |
801c135c AB |
1103 | struct ubi_vid_hdr *vid_hdr) |
1104 | { | |
1105 | int err; | |
1106 | uint32_t crc; | |
1107 | void *p; | |
1108 | ||
1109 | dbg_io("write VID header to PEB %d", pnum); | |
1110 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); | |
1111 | ||
1112 | err = paranoid_check_peb_ec_hdr(ubi, pnum); | |
1113 | if (err) | |
adbf05e3 | 1114 | return err; |
801c135c | 1115 | |
3261ebd7 | 1116 | vid_hdr->magic = cpu_to_be32(UBI_VID_HDR_MAGIC); |
801c135c AB |
1117 | vid_hdr->version = UBI_VERSION; |
1118 | crc = crc32(UBI_CRC32_INIT, vid_hdr, UBI_VID_HDR_SIZE_CRC); | |
3261ebd7 | 1119 | vid_hdr->hdr_crc = cpu_to_be32(crc); |
801c135c AB |
1120 | |
1121 | err = paranoid_check_vid_hdr(ubi, pnum, vid_hdr); | |
1122 | if (err) | |
adbf05e3 | 1123 | return err; |
801c135c AB |
1124 | |
1125 | p = (char *)vid_hdr - ubi->vid_hdr_shift; | |
1126 | err = ubi_io_write(ubi, p, pnum, ubi->vid_hdr_aloffset, | |
1127 | ubi->vid_hdr_alsize); | |
1128 | return err; | |
1129 | } | |
1130 | ||
1131 | #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID | |
1132 | ||
1133 | /** | |
1134 | * paranoid_check_not_bad - ensure that a physical eraseblock is not bad. | |
1135 | * @ubi: UBI device description object | |
1136 | * @pnum: physical eraseblock number to check | |
1137 | * | |
adbf05e3 AB |
1138 | * This function returns zero if the physical eraseblock is good, %-EINVAL if |
1139 | * it is bad and a negative error code if an error occurred. | |
801c135c AB |
1140 | */ |
1141 | static int paranoid_check_not_bad(const struct ubi_device *ubi, int pnum) | |
1142 | { | |
1143 | int err; | |
1144 | ||
1145 | err = ubi_io_is_bad(ubi, pnum); | |
1146 | if (!err) | |
1147 | return err; | |
1148 | ||
1149 | ubi_err("paranoid check failed for PEB %d", pnum); | |
1150 | ubi_dbg_dump_stack(); | |
adbf05e3 | 1151 | return err > 0 ? -EINVAL : err; |
801c135c AB |
1152 | } |
1153 | ||
1154 | /** | |
1155 | * paranoid_check_ec_hdr - check if an erase counter header is all right. | |
1156 | * @ubi: UBI device description object | |
1157 | * @pnum: physical eraseblock number the erase counter header belongs to | |
1158 | * @ec_hdr: the erase counter header to check | |
1159 | * | |
1160 | * This function returns zero if the erase counter header contains valid | |
adbf05e3 | 1161 | * values, and %-EINVAL if not. |
801c135c AB |
1162 | */ |
1163 | static int paranoid_check_ec_hdr(const struct ubi_device *ubi, int pnum, | |
1164 | const struct ubi_ec_hdr *ec_hdr) | |
1165 | { | |
1166 | int err; | |
1167 | uint32_t magic; | |
1168 | ||
3261ebd7 | 1169 | magic = be32_to_cpu(ec_hdr->magic); |
801c135c AB |
1170 | if (magic != UBI_EC_HDR_MAGIC) { |
1171 | ubi_err("bad magic %#08x, must be %#08x", | |
1172 | magic, UBI_EC_HDR_MAGIC); | |
1173 | goto fail; | |
1174 | } | |
1175 | ||
1176 | err = validate_ec_hdr(ubi, ec_hdr); | |
1177 | if (err) { | |
1178 | ubi_err("paranoid check failed for PEB %d", pnum); | |
1179 | goto fail; | |
1180 | } | |
1181 | ||
1182 | return 0; | |
1183 | ||
1184 | fail: | |
1185 | ubi_dbg_dump_ec_hdr(ec_hdr); | |
1186 | ubi_dbg_dump_stack(); | |
adbf05e3 | 1187 | return -EINVAL; |
801c135c AB |
1188 | } |
1189 | ||
1190 | /** | |
ebaaf1af | 1191 | * paranoid_check_peb_ec_hdr - check erase counter header. |
801c135c AB |
1192 | * @ubi: UBI device description object |
1193 | * @pnum: the physical eraseblock number to check | |
1194 | * | |
adbf05e3 AB |
1195 | * This function returns zero if the erase counter header is all right and and |
1196 | * a negative error code if not or if an error occurred. | |
801c135c AB |
1197 | */ |
1198 | static int paranoid_check_peb_ec_hdr(const struct ubi_device *ubi, int pnum) | |
1199 | { | |
1200 | int err; | |
1201 | uint32_t crc, hdr_crc; | |
1202 | struct ubi_ec_hdr *ec_hdr; | |
1203 | ||
33818bbb | 1204 | ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_NOFS); |
801c135c AB |
1205 | if (!ec_hdr) |
1206 | return -ENOMEM; | |
1207 | ||
1208 | err = ubi_io_read(ubi, ec_hdr, pnum, 0, UBI_EC_HDR_SIZE); | |
1209 | if (err && err != UBI_IO_BITFLIPS && err != -EBADMSG) | |
1210 | goto exit; | |
1211 | ||
1212 | crc = crc32(UBI_CRC32_INIT, ec_hdr, UBI_EC_HDR_SIZE_CRC); | |
3261ebd7 | 1213 | hdr_crc = be32_to_cpu(ec_hdr->hdr_crc); |
801c135c AB |
1214 | if (hdr_crc != crc) { |
1215 | ubi_err("bad CRC, calculated %#08x, read %#08x", crc, hdr_crc); | |
1216 | ubi_err("paranoid check failed for PEB %d", pnum); | |
1217 | ubi_dbg_dump_ec_hdr(ec_hdr); | |
1218 | ubi_dbg_dump_stack(); | |
adbf05e3 | 1219 | err = -EINVAL; |
801c135c AB |
1220 | goto exit; |
1221 | } | |
1222 | ||
1223 | err = paranoid_check_ec_hdr(ubi, pnum, ec_hdr); | |
1224 | ||
1225 | exit: | |
1226 | kfree(ec_hdr); | |
1227 | return err; | |
1228 | } | |
1229 | ||
1230 | /** | |
1231 | * paranoid_check_vid_hdr - check that a volume identifier header is all right. | |
1232 | * @ubi: UBI device description object | |
1233 | * @pnum: physical eraseblock number the volume identifier header belongs to | |
1234 | * @vid_hdr: the volume identifier header to check | |
1235 | * | |
1236 | * This function returns zero if the volume identifier header is all right, and | |
adbf05e3 | 1237 | * %-EINVAL if not. |
801c135c AB |
1238 | */ |
1239 | static int paranoid_check_vid_hdr(const struct ubi_device *ubi, int pnum, | |
1240 | const struct ubi_vid_hdr *vid_hdr) | |
1241 | { | |
1242 | int err; | |
1243 | uint32_t magic; | |
1244 | ||
3261ebd7 | 1245 | magic = be32_to_cpu(vid_hdr->magic); |
801c135c AB |
1246 | if (magic != UBI_VID_HDR_MAGIC) { |
1247 | ubi_err("bad VID header magic %#08x at PEB %d, must be %#08x", | |
1248 | magic, pnum, UBI_VID_HDR_MAGIC); | |
1249 | goto fail; | |
1250 | } | |
1251 | ||
1252 | err = validate_vid_hdr(ubi, vid_hdr); | |
1253 | if (err) { | |
1254 | ubi_err("paranoid check failed for PEB %d", pnum); | |
1255 | goto fail; | |
1256 | } | |
1257 | ||
1258 | return err; | |
1259 | ||
1260 | fail: | |
1261 | ubi_err("paranoid check failed for PEB %d", pnum); | |
1262 | ubi_dbg_dump_vid_hdr(vid_hdr); | |
1263 | ubi_dbg_dump_stack(); | |
adbf05e3 | 1264 | return -EINVAL; |
801c135c AB |
1265 | |
1266 | } | |
1267 | ||
1268 | /** | |
ebaaf1af | 1269 | * paranoid_check_peb_vid_hdr - check volume identifier header. |
801c135c AB |
1270 | * @ubi: UBI device description object |
1271 | * @pnum: the physical eraseblock number to check | |
1272 | * | |
1273 | * This function returns zero if the volume identifier header is all right, | |
adbf05e3 | 1274 | * and a negative error code if not or if an error occurred. |
801c135c AB |
1275 | */ |
1276 | static int paranoid_check_peb_vid_hdr(const struct ubi_device *ubi, int pnum) | |
1277 | { | |
1278 | int err; | |
1279 | uint32_t crc, hdr_crc; | |
1280 | struct ubi_vid_hdr *vid_hdr; | |
1281 | void *p; | |
1282 | ||
33818bbb | 1283 | vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS); |
801c135c AB |
1284 | if (!vid_hdr) |
1285 | return -ENOMEM; | |
1286 | ||
1287 | p = (char *)vid_hdr - ubi->vid_hdr_shift; | |
1288 | err = ubi_io_read(ubi, p, pnum, ubi->vid_hdr_aloffset, | |
1289 | ubi->vid_hdr_alsize); | |
1290 | if (err && err != UBI_IO_BITFLIPS && err != -EBADMSG) | |
1291 | goto exit; | |
1292 | ||
1293 | crc = crc32(UBI_CRC32_INIT, vid_hdr, UBI_EC_HDR_SIZE_CRC); | |
3261ebd7 | 1294 | hdr_crc = be32_to_cpu(vid_hdr->hdr_crc); |
801c135c AB |
1295 | if (hdr_crc != crc) { |
1296 | ubi_err("bad VID header CRC at PEB %d, calculated %#08x, " | |
1297 | "read %#08x", pnum, crc, hdr_crc); | |
1298 | ubi_err("paranoid check failed for PEB %d", pnum); | |
1299 | ubi_dbg_dump_vid_hdr(vid_hdr); | |
1300 | ubi_dbg_dump_stack(); | |
adbf05e3 | 1301 | err = -EINVAL; |
801c135c AB |
1302 | goto exit; |
1303 | } | |
1304 | ||
1305 | err = paranoid_check_vid_hdr(ubi, pnum, vid_hdr); | |
1306 | ||
1307 | exit: | |
1308 | ubi_free_vid_hdr(ubi, vid_hdr); | |
1309 | return err; | |
1310 | } | |
1311 | ||
6e9065d7 AB |
1312 | /** |
1313 | * ubi_dbg_check_write - make sure write succeeded. | |
1314 | * @ubi: UBI device description object | |
1315 | * @buf: buffer with data which were written | |
1316 | * @pnum: physical eraseblock number the data were written to | |
1317 | * @offset: offset within the physical eraseblock the data were written to | |
1318 | * @len: how many bytes were written | |
1319 | * | |
1320 | * This functions reads data which were recently written and compares it with | |
1321 | * the original data buffer - the data have to match. Returns zero if the data | |
1322 | * match and a negative error code if not or in case of failure. | |
1323 | */ | |
1324 | int ubi_dbg_check_write(struct ubi_device *ubi, const void *buf, int pnum, | |
1325 | int offset, int len) | |
1326 | { | |
1327 | int err, i; | |
7950d023 AB |
1328 | size_t read; |
1329 | loff_t addr = (loff_t)pnum * ubi->peb_size + offset; | |
6e9065d7 AB |
1330 | |
1331 | mutex_lock(&ubi->dbg_buf_mutex); | |
7950d023 AB |
1332 | err = ubi->mtd->read(ubi->mtd, addr, len, &read, ubi->dbg_peb_buf); |
1333 | if (err && err != -EUCLEAN) | |
6e9065d7 AB |
1334 | goto out_unlock; |
1335 | ||
1336 | for (i = 0; i < len; i++) { | |
1337 | uint8_t c = ((uint8_t *)buf)[i]; | |
1338 | uint8_t c1 = ((uint8_t *)ubi->dbg_peb_buf)[i]; | |
1339 | int dump_len; | |
1340 | ||
1341 | if (c == c1) | |
1342 | continue; | |
1343 | ||
1344 | ubi_err("paranoid check failed for PEB %d:%d, len %d", | |
1345 | pnum, offset, len); | |
1346 | ubi_msg("data differ at position %d", i); | |
1347 | dump_len = max_t(int, 128, len - i); | |
1348 | ubi_msg("hex dump of the original buffer from %d to %d", | |
1349 | i, i + dump_len); | |
1350 | print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1, | |
1351 | buf + i, dump_len, 1); | |
1352 | ubi_msg("hex dump of the read buffer from %d to %d", | |
1353 | i, i + dump_len); | |
1354 | print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1, | |
1355 | ubi->dbg_peb_buf + i, dump_len, 1); | |
1356 | ubi_dbg_dump_stack(); | |
1357 | err = -EINVAL; | |
1358 | goto out_unlock; | |
1359 | } | |
1360 | mutex_unlock(&ubi->dbg_buf_mutex); | |
1361 | ||
1362 | return 0; | |
1363 | ||
1364 | out_unlock: | |
1365 | mutex_unlock(&ubi->dbg_buf_mutex); | |
1366 | return err; | |
1367 | } | |
1368 | ||
801c135c | 1369 | /** |
40a71a87 | 1370 | * ubi_dbg_check_all_ff - check that a region of flash is empty. |
801c135c AB |
1371 | * @ubi: UBI device description object |
1372 | * @pnum: the physical eraseblock number to check | |
1373 | * @offset: the starting offset within the physical eraseblock to check | |
1374 | * @len: the length of the region to check | |
1375 | * | |
1376 | * This function returns zero if only 0xFF bytes are present at offset | |
adbf05e3 AB |
1377 | * @offset of the physical eraseblock @pnum, and a negative error code if not |
1378 | * or if an error occurred. | |
801c135c | 1379 | */ |
40a71a87 | 1380 | int ubi_dbg_check_all_ff(struct ubi_device *ubi, int pnum, int offset, int len) |
801c135c AB |
1381 | { |
1382 | size_t read; | |
1383 | int err; | |
801c135c AB |
1384 | loff_t addr = (loff_t)pnum * ubi->peb_size + offset; |
1385 | ||
e88d6e10 AB |
1386 | mutex_lock(&ubi->dbg_buf_mutex); |
1387 | err = ubi->mtd->read(ubi->mtd, addr, len, &read, ubi->dbg_peb_buf); | |
801c135c AB |
1388 | if (err && err != -EUCLEAN) { |
1389 | ubi_err("error %d while reading %d bytes from PEB %d:%d, " | |
1390 | "read %zd bytes", err, len, pnum, offset, read); | |
1391 | goto error; | |
1392 | } | |
1393 | ||
bb00e180 | 1394 | err = ubi_check_pattern(ubi->dbg_peb_buf, 0xFF, len); |
801c135c AB |
1395 | if (err == 0) { |
1396 | ubi_err("flash region at PEB %d:%d, length %d does not " | |
1397 | "contain all 0xFF bytes", pnum, offset, len); | |
1398 | goto fail; | |
1399 | } | |
e88d6e10 | 1400 | mutex_unlock(&ubi->dbg_buf_mutex); |
801c135c | 1401 | |
801c135c AB |
1402 | return 0; |
1403 | ||
1404 | fail: | |
1405 | ubi_err("paranoid check failed for PEB %d", pnum); | |
c8566350 | 1406 | ubi_msg("hex dump of the %d-%d region", offset, offset + len); |
6986646b | 1407 | print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1, |
e88d6e10 | 1408 | ubi->dbg_peb_buf, len, 1); |
adbf05e3 | 1409 | err = -EINVAL; |
801c135c AB |
1410 | error: |
1411 | ubi_dbg_dump_stack(); | |
e88d6e10 | 1412 | mutex_unlock(&ubi->dbg_buf_mutex); |
801c135c AB |
1413 | return err; |
1414 | } | |
1415 | ||
1416 | #endif /* CONFIG_MTD_UBI_DEBUG_PARANOID */ |