1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Copyright (c) International Business Machines Corp., 2006 |
4 | * Copyright (c) Nokia Corporation, 2006, 2007 |
5 | * |
6 | * Author: Artem Bityutskiy (Битюцкий Артём) |
7 | */ |
8 | |
9 | /* |
10 | * UBI input/output sub-system. |
11 | * |
12 | * This sub-system provides a uniform way to work with all kinds of the |
13 | * underlying MTD devices. It also implements handy functions for reading and |
14 | * writing UBI headers. |
15 | * |
16 | * We are trying to have a paranoid mindset and not to trust to what we read |
17 | * from the flash media in order to be more secure and robust. So this |
18 | * sub-system validates every single header it reads from the flash media. |
19 | * |
20 | * Some words about how the eraseblock headers are stored. |
21 | * |
22 | * The erase counter header is always stored at offset zero. By default, the |
23 | * VID header is stored after the EC header at the closest aligned offset |
24 | * (i.e. aligned to the minimum I/O unit size). Data starts next to the VID |
25 | * header at the closest aligned offset. But this default layout may be |
26 | * changed. For example, for different reasons (e.g., optimization) UBI may be |
27 | * asked to put the VID header at further offset, and even at an unaligned |
28 | * offset. Of course, if the offset of the VID header is unaligned, UBI adds |
29 | * proper padding in front of it. Data offset may also be changed but it has to |
30 | * be aligned. |
31 | * |
32 | * About minimal I/O units. In general, UBI assumes flash device model where |
33 | * there is only one minimal I/O unit size. E.g., in case of NOR flash it is 1, |
34 | * in case of NAND flash it is a NAND page, etc. This is reported by MTD in the |
35 | * @ubi->mtd->writesize field. But as an exception, UBI admits use of another |
36 | * (smaller) minimal I/O unit size for EC and VID headers to make it possible |
37 | * to do different optimizations. |
38 | * |
39 | * This is extremely useful in case of NAND flashes which admit of several |
40 | * write operations to one NAND page. In this case UBI can fit EC and VID |
41 | * headers at one NAND page. Thus, UBI may use "sub-page" size as the minimal |
42 | * I/O unit for the headers (the @ubi->hdrs_min_io_size field). But it still |
43 | * reports NAND page size (@ubi->min_io_size) as a minimal I/O unit for the UBI |
44 | * users. |
45 | * |
46 | * Example: some Samsung NANDs with 2KiB pages allow 4x 512-byte writes, so |
47 | * although the minimal I/O unit is 2K, UBI uses 512 bytes for EC and VID |
48 | * headers. |
49 | * |
50 | * Q: why not just to treat sub-page as a minimal I/O unit of this flash |
51 | * device, e.g., make @ubi->min_io_size = 512 in the example above? |
52 | * |
53 | * A: because when writing a sub-page, MTD still writes a full 2K page but the |
54 | * bytes which are not relevant to the sub-page are 0xFF. So, basically, |
55 | * writing 4x512 sub-pages is 4 times slower than writing one 2KiB NAND page. |
56 | * Thus, we prefer to use sub-pages only for EC and VID headers. |
57 | * |
58 | * As it was noted above, the VID header may start at a non-aligned offset. |
59 | * For example, in case of a 2KiB page NAND flash with a 512 bytes sub-page, |
60 | * the VID header may reside at offset 1984 which is the last 64 bytes of the |
61 | * last sub-page (EC header is always at offset zero). This causes some |
62 | * difficulties when reading and writing VID headers. |
63 | * |
64 | * Suppose we have a 64-byte buffer and we read a VID header at it. We change |
65 | * the data and want to write this VID header out. As we can only write in |
66 | * 512-byte chunks, we have to allocate one more buffer and copy our VID header |
67 | * to offset 448 of this buffer. |
68 | * |
69 | * The I/O sub-system does the following trick in order to avoid this extra |
70 | * copy. It always allocates a @ubi->vid_hdr_alsize bytes buffer for the VID |
71 | * header and returns a pointer to offset @ubi->vid_hdr_shift of this buffer. |
72 | * When the VID header is being written out, it shifts the VID header pointer |
73 | * back and writes the whole sub-page. |
74 | */ |
75 | |
76 | #include <linux/crc32.h> |
77 | #include <linux/err.h> |
78 | #include <linux/slab.h> |
79 | #include "ubi.h" |
80 | |
81 | static int self_check_not_bad(const struct ubi_device *ubi, int pnum); |
82 | static int self_check_peb_ec_hdr(const struct ubi_device *ubi, int pnum); |
83 | static int self_check_ec_hdr(const struct ubi_device *ubi, int pnum, |
84 | const struct ubi_ec_hdr *ec_hdr); |
85 | static int self_check_peb_vid_hdr(const struct ubi_device *ubi, int pnum); |
86 | static int self_check_vid_hdr(const struct ubi_device *ubi, int pnum, |
87 | const struct ubi_vid_hdr *vid_hdr); |
88 | static int self_check_write(struct ubi_device *ubi, const void *buf, int pnum, |
89 | int offset, int len); |
90 | |
91 | /** |
92 | * ubi_io_read - read data from a physical eraseblock. |
93 | * @ubi: UBI device description object |
94 | * @buf: buffer where to store the read data |
95 | * @pnum: physical eraseblock number to read from |
96 | * @offset: offset within the physical eraseblock from where to read |
97 | * @len: how many bytes to read |
98 | * |
99 | * This function reads data from offset @offset of physical eraseblock @pnum |
100 | * and stores the read data in the @buf buffer. The following return codes are |
101 | * possible: |
102 | * |
103 | * o %0 if all the requested data were successfully read; |
104 | * o %UBI_IO_BITFLIPS if all the requested data were successfully read, but |
105 | * correctable bit-flips were detected; this is harmless but may indicate |
106 | * that this eraseblock may become bad soon (but do not have to); |
107 | * o %-EBADMSG if the MTD subsystem reported about data integrity problems, for |
108 | * example it can be an ECC error in case of NAND; this most probably means |
109 | * that the data is corrupted; |
110 | * o %-EIO if some I/O error occurred; |
111 | * o other negative error codes in case of other errors. |
112 | */ |
113 | int ubi_io_read(const struct ubi_device *ubi, void *buf, int pnum, int offset, |
114 | int len) |
115 | { |
116 | int err, retries = 0; |
117 | size_t read; |
118 | loff_t addr; |
119 | |
120 | dbg_io("read %d bytes from PEB %d:%d" , len, pnum, offset); |
121 | |
122 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); |
123 | ubi_assert(offset >= 0 && offset + len <= ubi->peb_size); |
124 | ubi_assert(len > 0); |
125 | |
126 | err = self_check_not_bad(ubi, pnum); |
127 | if (err) |
128 | return err; |
129 | |
130 | /* |
131 | * Deliberately corrupt the buffer to improve robustness. Indeed, if we |
132 | * do not do this, the following may happen: |
133 | * 1. The buffer contains data from previous operation, e.g., read from |
134 | * another PEB previously. The data looks like expected, e.g., if we |
135 | * just do not read anything and return - the caller would not |
136 | * notice this. E.g., if we are reading a VID header, the buffer may |
137 | * contain a valid VID header from another PEB. |
138 | * 2. The driver is buggy and returns us success or -EBADMSG or |
139 | * -EUCLEAN, but it does not actually put any data to the buffer. |
140 | * |
141 | * This may confuse UBI or upper layers - they may think the buffer |
142 | * contains valid data while in fact it is just old data. This is |
143 | * especially possible because UBI (and UBIFS) relies on CRC, and |
144 | * treats data as correct even in case of ECC errors if the CRC is |
145 | * correct. |
146 | * |
147 | * Try to prevent this situation by changing the first byte of the |
148 | * buffer. |
149 | */ |
150 | *((uint8_t *)buf) ^= 0xFF; |
151 | |
152 | addr = (loff_t)pnum * ubi->peb_size + offset; |
153 | retry: |
154 | err = mtd_read(mtd: ubi->mtd, from: addr, len, retlen: &read, buf); |
155 | if (err) { |
156 | const char *errstr = mtd_is_eccerr(err) ? " (ECC error)" : "" ; |
157 | |
158 | if (mtd_is_bitflip(err)) { |
159 | /* |
160 | * -EUCLEAN is reported if there was a bit-flip which |
161 | * was corrected, so this is harmless. |
162 | * |
163 | * We do not report about it here unless debugging is |
164 | * enabled. A corresponding message will be printed |
165 | * later, when it is has been scrubbed. |
166 | */ |
167 | ubi_msg(ubi, fmt: "fixable bit-flip detected at PEB %d" , |
168 | pnum); |
169 | ubi_assert(len == read); |
170 | return UBI_IO_BITFLIPS; |
171 | } |
172 | |
173 | if (retries++ < UBI_IO_RETRIES) { |
174 | ubi_warn(ubi, fmt: "error %d%s while reading %d bytes from PEB %d:%d, read only %zd bytes, retry" , |
175 | err, errstr, len, pnum, offset, read); |
176 | yield(); |
177 | goto retry; |
178 | } |
179 | |
180 | ubi_err(ubi, fmt: "error %d%s while reading %d bytes from PEB %d:%d, read %zd bytes" , |
181 | err, errstr, len, pnum, offset, read); |
182 | dump_stack(); |
183 | |
184 | /* |
185 | * The driver should never return -EBADMSG if it failed to read |
186 | * all the requested data. But some buggy drivers might do |
187 | * this, so we change it to -EIO. |
188 | */ |
189 | if (read != len && mtd_is_eccerr(err)) { |
190 | ubi_assert(0); |
191 | err = -EIO; |
192 | } |
193 | } else { |
194 | ubi_assert(len == read); |
195 | |
196 | if (ubi_dbg_is_bitflip(ubi)) { |
197 | dbg_gen("bit-flip (emulated)" ); |
198 | return UBI_IO_BITFLIPS; |
199 | } |
200 | |
201 | if (ubi_dbg_is_read_failure(ubi, MASK_READ_FAILURE)) { |
202 | ubi_warn(ubi, fmt: "cannot read %d bytes from PEB %d:%d (emulated)" , |
203 | len, pnum, offset); |
204 | return -EIO; |
205 | } |
206 | |
207 | if (ubi_dbg_is_eccerr(ubi)) { |
208 | ubi_warn(ubi, fmt: "ECC error (emulated) while reading %d bytes from PEB %d:%d, read %zd bytes" , |
209 | len, pnum, offset, read); |
210 | return -EBADMSG; |
211 | } |
212 | } |
213 | |
214 | return err; |
215 | } |
216 | |
217 | /** |
218 | * ubi_io_write - write data to a physical eraseblock. |
219 | * @ubi: UBI device description object |
220 | * @buf: buffer with the data to write |
221 | * @pnum: physical eraseblock number to write to |
222 | * @offset: offset within the physical eraseblock where to write |
223 | * @len: how many bytes to write |
224 | * |
225 | * This function writes @len bytes of data from buffer @buf to offset @offset |
226 | * of physical eraseblock @pnum. If all the data were successfully written, |
227 | * zero is returned. If an error occurred, this function returns a negative |
228 | * error code. If %-EIO is returned, the physical eraseblock most probably went |
229 | * bad. |
230 | * |
231 | * Note, in case of an error, it is possible that something was still written |
232 | * to the flash media, but may be some garbage. |
233 | */ |
234 | int ubi_io_write(struct ubi_device *ubi, const void *buf, int pnum, int offset, |
235 | int len) |
236 | { |
237 | int err; |
238 | size_t written; |
239 | loff_t addr; |
240 | |
241 | dbg_io("write %d bytes to PEB %d:%d" , len, pnum, offset); |
242 | |
243 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); |
244 | ubi_assert(offset >= 0 && offset + len <= ubi->peb_size); |
245 | ubi_assert(offset % ubi->hdrs_min_io_size == 0); |
246 | ubi_assert(len > 0 && len % ubi->hdrs_min_io_size == 0); |
247 | |
248 | if (ubi->ro_mode) { |
249 | ubi_err(ubi, fmt: "read-only mode" ); |
250 | return -EROFS; |
251 | } |
252 | |
253 | err = self_check_not_bad(ubi, pnum); |
254 | if (err) |
255 | return err; |
256 | |
257 | /* The area we are writing to has to contain all 0xFF bytes */ |
258 | err = ubi_self_check_all_ff(ubi, pnum, offset, len); |
259 | if (err) |
260 | return err; |
261 | |
262 | if (offset >= ubi->leb_start) { |
263 | /* |
264 | * We write to the data area of the physical eraseblock. Make |
265 | * sure it has valid EC and VID headers. |
266 | */ |
267 | err = self_check_peb_ec_hdr(ubi, pnum); |
268 | if (err) |
269 | return err; |
270 | err = self_check_peb_vid_hdr(ubi, pnum); |
271 | if (err) |
272 | return err; |
273 | } |
274 | |
275 | if (ubi_dbg_is_write_failure(ubi)) { |
276 | ubi_err(ubi, fmt: "cannot write %d bytes to PEB %d:%d (emulated)" , |
277 | len, pnum, offset); |
278 | dump_stack(); |
279 | return -EIO; |
280 | } |
281 | |
282 | addr = (loff_t)pnum * ubi->peb_size + offset; |
283 | err = mtd_write(mtd: ubi->mtd, to: addr, len, retlen: &written, buf); |
284 | if (err) { |
285 | ubi_err(ubi, fmt: "error %d while writing %d bytes to PEB %d:%d, written %zd bytes" , |
286 | err, len, pnum, offset, written); |
287 | dump_stack(); |
288 | ubi_dump_flash(ubi, pnum, offset, len); |
289 | } else |
290 | ubi_assert(written == len); |
291 | |
292 | if (!err) { |
293 | err = self_check_write(ubi, buf, pnum, offset, len); |
294 | if (err) |
295 | return err; |
296 | |
297 | /* |
298 | * Since we always write sequentially, the rest of the PEB has |
299 | * to contain only 0xFF bytes. |
300 | */ |
301 | offset += len; |
302 | len = ubi->peb_size - offset; |
303 | if (len) |
304 | err = ubi_self_check_all_ff(ubi, pnum, offset, len); |
305 | } |
306 | |
307 | return err; |
308 | } |
309 | |
310 | /** |
311 | * do_sync_erase - synchronously erase a physical eraseblock. |
312 | * @ubi: UBI device description object |
313 | * @pnum: the physical eraseblock number to erase |
314 | * |
315 | * This function synchronously erases physical eraseblock @pnum and returns |
316 | * zero in case of success and a negative error code in case of failure. If |
317 | * %-EIO is returned, the physical eraseblock most probably went bad. |
318 | */ |
319 | static int do_sync_erase(struct ubi_device *ubi, int pnum) |
320 | { |
321 | int err, retries = 0; |
322 | struct erase_info ei; |
323 | |
324 | dbg_io("erase PEB %d" , pnum); |
325 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); |
326 | |
327 | if (ubi->ro_mode) { |
328 | ubi_err(ubi, fmt: "read-only mode" ); |
329 | return -EROFS; |
330 | } |
331 | |
332 | retry: |
333 | memset(&ei, 0, sizeof(struct erase_info)); |
334 | |
335 | ei.addr = (loff_t)pnum * ubi->peb_size; |
336 | ei.len = ubi->peb_size; |
337 | |
338 | err = mtd_erase(mtd: ubi->mtd, instr: &ei); |
339 | if (err) { |
340 | if (retries++ < UBI_IO_RETRIES) { |
341 | ubi_warn(ubi, fmt: "error %d while erasing PEB %d, retry" , |
342 | err, pnum); |
343 | yield(); |
344 | goto retry; |
345 | } |
346 | ubi_err(ubi, fmt: "cannot erase PEB %d, error %d" , pnum, err); |
347 | dump_stack(); |
348 | return err; |
349 | } |
350 | |
351 | err = ubi_self_check_all_ff(ubi, pnum, offset: 0, len: ubi->peb_size); |
352 | if (err) |
353 | return err; |
354 | |
355 | if (ubi_dbg_is_erase_failure(ubi)) { |
356 | ubi_err(ubi, fmt: "cannot erase PEB %d (emulated)" , pnum); |
357 | return -EIO; |
358 | } |
359 | |
360 | return 0; |
361 | } |
362 | |
363 | /* Patterns to write to a physical eraseblock when torturing it */ |
364 | static uint8_t patterns[] = {0xa5, 0x5a, 0x0}; |
365 | |
366 | /** |
367 | * torture_peb - test a supposedly bad physical eraseblock. |
368 | * @ubi: UBI device description object |
369 | * @pnum: the physical eraseblock number to test |
370 | * |
371 | * This function returns %-EIO if the physical eraseblock did not pass the |
372 | * test, a positive number of erase operations done if the test was |
373 | * successfully passed, and other negative error codes in case of other errors. |
374 | */ |
375 | static int torture_peb(struct ubi_device *ubi, int pnum) |
376 | { |
377 | int err, i, patt_count; |
378 | |
379 | ubi_msg(ubi, fmt: "run torture test for PEB %d" , pnum); |
380 | patt_count = ARRAY_SIZE(patterns); |
381 | ubi_assert(patt_count > 0); |
382 | |
383 | mutex_lock(&ubi->buf_mutex); |
384 | for (i = 0; i < patt_count; i++) { |
385 | err = do_sync_erase(ubi, pnum); |
386 | if (err) |
387 | goto out; |
388 | |
389 | /* Make sure the PEB contains only 0xFF bytes */ |
390 | err = ubi_io_read(ubi, buf: ubi->peb_buf, pnum, offset: 0, len: ubi->peb_size); |
391 | if (err) |
392 | goto out; |
393 | |
394 | err = ubi_check_pattern(buf: ubi->peb_buf, patt: 0xFF, size: ubi->peb_size); |
395 | if (err == 0) { |
396 | ubi_err(ubi, fmt: "erased PEB %d, but a non-0xFF byte found" , |
397 | pnum); |
398 | err = -EIO; |
399 | goto out; |
400 | } |
401 | |
402 | /* Write a pattern and check it */ |
403 | memset(ubi->peb_buf, patterns[i], ubi->peb_size); |
404 | err = ubi_io_write(ubi, buf: ubi->peb_buf, pnum, offset: 0, len: ubi->peb_size); |
405 | if (err) |
406 | goto out; |
407 | |
408 | memset(ubi->peb_buf, ~patterns[i], ubi->peb_size); |
409 | err = ubi_io_read(ubi, buf: ubi->peb_buf, pnum, offset: 0, len: ubi->peb_size); |
410 | if (err) |
411 | goto out; |
412 | |
413 | err = ubi_check_pattern(buf: ubi->peb_buf, patt: patterns[i], |
414 | size: ubi->peb_size); |
415 | if (err == 0) { |
416 | ubi_err(ubi, fmt: "pattern %x checking failed for PEB %d" , |
417 | patterns[i], pnum); |
418 | err = -EIO; |
419 | goto out; |
420 | } |
421 | } |
422 | |
423 | err = patt_count; |
424 | ubi_msg(ubi, fmt: "PEB %d passed torture test, do not mark it as bad" , pnum); |
425 | |
426 | out: |
427 | mutex_unlock(lock: &ubi->buf_mutex); |
428 | if (err == UBI_IO_BITFLIPS || mtd_is_eccerr(err)) { |
429 | /* |
430 | * If a bit-flip or data integrity error was detected, the test |
431 | * has not passed because it happened on a freshly erased |
432 | * physical eraseblock which means something is wrong with it. |
433 | */ |
434 | ubi_err(ubi, fmt: "read problems on freshly erased PEB %d, must be bad" , |
435 | pnum); |
436 | err = -EIO; |
437 | } |
438 | return err; |
439 | } |
440 | |
441 | /** |
442 | * nor_erase_prepare - prepare a NOR flash PEB for erasure. |
443 | * @ubi: UBI device description object |
444 | * @pnum: physical eraseblock number to prepare |
445 | * |
446 | * NOR flash, or at least some of them, have peculiar embedded PEB erasure |
447 | * algorithm: the PEB is first filled with zeroes, then it is erased. And |
448 | * filling with zeroes starts from the end of the PEB. This was observed with |
449 | * Spansion S29GL512N NOR flash. |
450 | * |
451 | * This means that in case of a power cut we may end up with intact data at the |
452 | * beginning of the PEB, and all zeroes at the end of PEB. In other words, the |
453 | * EC and VID headers are OK, but a large chunk of data at the end of PEB is |
454 | * zeroed. This makes UBI mistakenly treat this PEB as used and associate it |
455 | * with an LEB, which leads to subsequent failures (e.g., UBIFS fails). |
456 | * |
457 | * This function is called before erasing NOR PEBs and it zeroes out EC and VID |
458 | * magic numbers in order to invalidate them and prevent the failures. Returns |
459 | * zero in case of success and a negative error code in case of failure. |
460 | */ |
461 | static int nor_erase_prepare(struct ubi_device *ubi, int pnum) |
462 | { |
463 | int err; |
464 | size_t written; |
465 | loff_t addr; |
466 | uint32_t data = 0; |
467 | struct ubi_ec_hdr ec_hdr; |
468 | struct ubi_vid_io_buf vidb; |
469 | |
470 | /* |
471 | * Note, we cannot generally define VID header buffers on stack, |
472 | * because of the way we deal with these buffers (see the header |
473 | * comment in this file). But we know this is a NOR-specific piece of |
474 | * code, so we can do this. But yes, this is error-prone and we should |
475 | * (pre-)allocate VID header buffer instead. |
476 | */ |
477 | struct ubi_vid_hdr vid_hdr; |
478 | |
479 | /* |
480 | * If VID or EC is valid, we have to corrupt them before erasing. |
481 | * It is important to first invalidate the EC header, and then the VID |
482 | * header. Otherwise a power cut may lead to valid EC header and |
483 | * invalid VID header, in which case UBI will treat this PEB as |
484 | * corrupted and will try to preserve it, and print scary warnings. |
485 | */ |
486 | addr = (loff_t)pnum * ubi->peb_size; |
487 | err = ubi_io_read_ec_hdr(ubi, pnum, ec_hdr: &ec_hdr, verbose: 0); |
488 | if (err != UBI_IO_BAD_HDR_EBADMSG && err != UBI_IO_BAD_HDR && |
489 | err != UBI_IO_FF){ |
490 | err = mtd_write(mtd: ubi->mtd, to: addr, len: 4, retlen: &written, buf: (void *)&data); |
491 | if(err) |
492 | goto error; |
493 | } |
494 | |
495 | ubi_init_vid_buf(ubi, vidb: &vidb, buf: &vid_hdr); |
496 | ubi_assert(&vid_hdr == ubi_get_vid_hdr(&vidb)); |
497 | |
498 | err = ubi_io_read_vid_hdr(ubi, pnum, vidb: &vidb, verbose: 0); |
499 | if (err != UBI_IO_BAD_HDR_EBADMSG && err != UBI_IO_BAD_HDR && |
500 | err != UBI_IO_FF){ |
501 | addr += ubi->vid_hdr_aloffset; |
502 | err = mtd_write(mtd: ubi->mtd, to: addr, len: 4, retlen: &written, buf: (void *)&data); |
503 | if (err) |
504 | goto error; |
505 | } |
506 | return 0; |
507 | |
508 | error: |
509 | /* |
510 | * The PEB contains a valid VID or EC header, but we cannot invalidate |
511 | * it. Supposedly the flash media or the driver is screwed up, so |
512 | * return an error. |
513 | */ |
514 | ubi_err(ubi, fmt: "cannot invalidate PEB %d, write returned %d" , pnum, err); |
515 | ubi_dump_flash(ubi, pnum, offset: 0, len: ubi->peb_size); |
516 | return -EIO; |
517 | } |
518 | |
519 | /** |
520 | * ubi_io_sync_erase - synchronously erase a physical eraseblock. |
521 | * @ubi: UBI device description object |
522 | * @pnum: physical eraseblock number to erase |
523 | * @torture: if this physical eraseblock has to be tortured |
524 | * |
525 | * This function synchronously erases physical eraseblock @pnum. If @torture |
526 | * flag is not zero, the physical eraseblock is checked by means of writing |
527 | * different patterns to it and reading them back. If the torturing is enabled, |
528 | * the physical eraseblock is erased more than once. |
529 | * |
530 | * This function returns the number of erasures made in case of success, %-EIO |
531 | * if the erasure failed or the torturing test failed, and other negative error |
532 | * codes in case of other errors. Note, %-EIO means that the physical |
533 | * eraseblock is bad. |
534 | */ |
535 | int ubi_io_sync_erase(struct ubi_device *ubi, int pnum, int torture) |
536 | { |
537 | int err, ret = 0; |
538 | |
539 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); |
540 | |
541 | err = self_check_not_bad(ubi, pnum); |
542 | if (err != 0) |
543 | return err; |
544 | |
545 | if (ubi->ro_mode) { |
546 | ubi_err(ubi, fmt: "read-only mode" ); |
547 | return -EROFS; |
548 | } |
549 | |
550 | /* |
551 | * If the flash is ECC-ed then we have to erase the ECC block before we |
552 | * can write to it. But the write is in preparation to an erase in the |
553 | * first place. This means we cannot zero out EC and VID before the |
554 | * erase and we just have to hope the flash starts erasing from the |
555 | * start of the page. |
556 | */ |
557 | if (ubi->nor_flash && ubi->mtd->writesize == 1) { |
558 | err = nor_erase_prepare(ubi, pnum); |
559 | if (err) |
560 | return err; |
561 | } |
562 | |
563 | if (torture) { |
564 | ret = torture_peb(ubi, pnum); |
565 | if (ret < 0) |
566 | return ret; |
567 | } |
568 | |
569 | err = do_sync_erase(ubi, pnum); |
570 | if (err) |
571 | return err; |
572 | |
573 | return ret + 1; |
574 | } |
575 | |
576 | /** |
577 | * ubi_io_is_bad - check if a physical eraseblock is bad. |
578 | * @ubi: UBI device description object |
579 | * @pnum: the physical eraseblock number to check |
580 | * |
581 | * This function returns a positive number if the physical eraseblock is bad, |
582 | * zero if not, and a negative error code if an error occurred. |
583 | */ |
584 | int ubi_io_is_bad(const struct ubi_device *ubi, int pnum) |
585 | { |
586 | struct mtd_info *mtd = ubi->mtd; |
587 | |
588 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); |
589 | |
590 | if (ubi->bad_allowed) { |
591 | int ret; |
592 | |
593 | ret = mtd_block_isbad(mtd, ofs: (loff_t)pnum * ubi->peb_size); |
594 | if (ret < 0) |
595 | ubi_err(ubi, fmt: "error %d while checking if PEB %d is bad" , |
596 | ret, pnum); |
597 | else if (ret) |
598 | dbg_io("PEB %d is bad" , pnum); |
599 | return ret; |
600 | } |
601 | |
602 | return 0; |
603 | } |
604 | |
605 | /** |
606 | * ubi_io_mark_bad - mark a physical eraseblock as bad. |
607 | * @ubi: UBI device description object |
608 | * @pnum: the physical eraseblock number to mark |
609 | * |
610 | * This function returns zero in case of success and a negative error code in |
611 | * case of failure. |
612 | */ |
613 | int ubi_io_mark_bad(const struct ubi_device *ubi, int pnum) |
614 | { |
615 | int err; |
616 | struct mtd_info *mtd = ubi->mtd; |
617 | |
618 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); |
619 | |
620 | if (ubi->ro_mode) { |
621 | ubi_err(ubi, fmt: "read-only mode" ); |
622 | return -EROFS; |
623 | } |
624 | |
625 | if (!ubi->bad_allowed) |
626 | return 0; |
627 | |
628 | err = mtd_block_markbad(mtd, ofs: (loff_t)pnum * ubi->peb_size); |
629 | if (err) |
630 | ubi_err(ubi, fmt: "cannot mark PEB %d bad, error %d" , pnum, err); |
631 | return err; |
632 | } |
633 | |
634 | /** |
635 | * validate_ec_hdr - validate an erase counter header. |
636 | * @ubi: UBI device description object |
637 | * @ec_hdr: the erase counter header to check |
638 | * |
639 | * This function returns zero if the erase counter header is OK, and %1 if |
640 | * not. |
641 | */ |
642 | static int validate_ec_hdr(const struct ubi_device *ubi, |
643 | const struct ubi_ec_hdr *ec_hdr) |
644 | { |
645 | long long ec; |
646 | int vid_hdr_offset, leb_start; |
647 | |
648 | ec = be64_to_cpu(ec_hdr->ec); |
649 | vid_hdr_offset = be32_to_cpu(ec_hdr->vid_hdr_offset); |
650 | leb_start = be32_to_cpu(ec_hdr->data_offset); |
651 | |
652 | if (ec_hdr->version != UBI_VERSION) { |
653 | ubi_err(ubi, fmt: "node with incompatible UBI version found: this UBI version is %d, image version is %d" , |
654 | UBI_VERSION, (int)ec_hdr->version); |
655 | goto bad; |
656 | } |
657 | |
658 | if (vid_hdr_offset != ubi->vid_hdr_offset) { |
659 | ubi_err(ubi, fmt: "bad VID header offset %d, expected %d" , |
660 | vid_hdr_offset, ubi->vid_hdr_offset); |
661 | goto bad; |
662 | } |
663 | |
664 | if (leb_start != ubi->leb_start) { |
665 | ubi_err(ubi, fmt: "bad data offset %d, expected %d" , |
666 | leb_start, ubi->leb_start); |
667 | goto bad; |
668 | } |
669 | |
670 | if (ec < 0 || ec > UBI_MAX_ERASECOUNTER) { |
671 | ubi_err(ubi, fmt: "bad erase counter %lld" , ec); |
672 | goto bad; |
673 | } |
674 | |
675 | return 0; |
676 | |
677 | bad: |
678 | ubi_err(ubi, fmt: "bad EC header" ); |
679 | ubi_dump_ec_hdr(ec_hdr); |
680 | dump_stack(); |
681 | return 1; |
682 | } |
683 | |
684 | /** |
685 | * ubi_io_read_ec_hdr - read and check an erase counter header. |
686 | * @ubi: UBI device description object |
687 | * @pnum: physical eraseblock to read from |
688 | * @ec_hdr: a &struct ubi_ec_hdr object where to store the read erase counter |
689 | * header |
690 | * @verbose: be verbose if the header is corrupted or was not found |
691 | * |
692 | * This function reads erase counter header from physical eraseblock @pnum and |
693 | * stores it in @ec_hdr. This function also checks CRC checksum of the read |
694 | * erase counter header. The following codes may be returned: |
695 | * |
696 | * o %0 if the CRC checksum is correct and the header was successfully read; |
697 | * o %UBI_IO_BITFLIPS if the CRC is correct, but bit-flips were detected |
698 | * and corrected by the flash driver; this is harmless but may indicate that |
699 | * this eraseblock may become bad soon (but may be not); |
700 | * o %UBI_IO_BAD_HDR if the erase counter header is corrupted (a CRC error); |
701 | * o %UBI_IO_BAD_HDR_EBADMSG is the same as %UBI_IO_BAD_HDR, but there also was |
702 | * a data integrity error (uncorrectable ECC error in case of NAND); |
703 | * o %UBI_IO_FF if only 0xFF bytes were read (the PEB is supposedly empty) |
704 | * o a negative error code in case of failure. |
705 | */ |
706 | int ubi_io_read_ec_hdr(struct ubi_device *ubi, int pnum, |
707 | struct ubi_ec_hdr *ec_hdr, int verbose) |
708 | { |
709 | int err, read_err; |
710 | uint32_t crc, magic, hdr_crc; |
711 | |
712 | dbg_io("read EC header from PEB %d" , pnum); |
713 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); |
714 | |
715 | read_err = ubi_io_read(ubi, buf: ec_hdr, pnum, offset: 0, UBI_EC_HDR_SIZE); |
716 | if (read_err) { |
717 | if (read_err != UBI_IO_BITFLIPS && !mtd_is_eccerr(err: read_err)) |
718 | return read_err; |
719 | |
720 | /* |
721 | * We read all the data, but either a correctable bit-flip |
722 | * occurred, or MTD reported a data integrity error |
723 | * (uncorrectable ECC error in case of NAND). The former is |
724 | * harmless, the later may mean that the read data is |
725 | * corrupted. But we have a CRC check-sum and we will detect |
726 | * this. If the EC header is still OK, we just report this as |
727 | * there was a bit-flip, to force scrubbing. |
728 | */ |
729 | } |
730 | |
731 | magic = be32_to_cpu(ec_hdr->magic); |
732 | if (magic != UBI_EC_HDR_MAGIC) { |
733 | if (mtd_is_eccerr(err: read_err)) |
734 | return UBI_IO_BAD_HDR_EBADMSG; |
735 | |
736 | /* |
737 | * The magic field is wrong. Let's check if we have read all |
738 | * 0xFF. If yes, this physical eraseblock is assumed to be |
739 | * empty. |
740 | */ |
741 | if (ubi_check_pattern(buf: ec_hdr, patt: 0xFF, UBI_EC_HDR_SIZE)) { |
742 | /* The physical eraseblock is supposedly empty */ |
743 | if (verbose) |
744 | ubi_warn(ubi, fmt: "no EC header found at PEB %d, only 0xFF bytes" , |
745 | pnum); |
746 | dbg_bld("no EC header found at PEB %d, only 0xFF bytes" , |
747 | pnum); |
748 | if (!read_err) |
749 | return UBI_IO_FF; |
750 | else |
751 | return UBI_IO_FF_BITFLIPS; |
752 | } |
753 | |
754 | /* |
755 | * This is not a valid erase counter header, and these are not |
756 | * 0xFF bytes. Report that the header is corrupted. |
757 | */ |
758 | if (verbose) { |
759 | ubi_warn(ubi, fmt: "bad magic number at PEB %d: %08x instead of %08x" , |
760 | pnum, magic, UBI_EC_HDR_MAGIC); |
761 | ubi_dump_ec_hdr(ec_hdr); |
762 | } |
763 | dbg_bld("bad magic number at PEB %d: %08x instead of %08x" , |
764 | pnum, magic, UBI_EC_HDR_MAGIC); |
765 | return UBI_IO_BAD_HDR; |
766 | } |
767 | |
768 | crc = crc32(UBI_CRC32_INIT, ec_hdr, UBI_EC_HDR_SIZE_CRC); |
769 | hdr_crc = be32_to_cpu(ec_hdr->hdr_crc); |
770 | |
771 | if (hdr_crc != crc) { |
772 | if (verbose) { |
773 | ubi_warn(ubi, fmt: "bad EC header CRC at PEB %d, calculated %#08x, read %#08x" , |
774 | pnum, crc, hdr_crc); |
775 | ubi_dump_ec_hdr(ec_hdr); |
776 | } |
777 | dbg_bld("bad EC header CRC at PEB %d, calculated %#08x, read %#08x" , |
778 | pnum, crc, hdr_crc); |
779 | |
780 | if (!read_err) |
781 | return UBI_IO_BAD_HDR; |
782 | else |
783 | return UBI_IO_BAD_HDR_EBADMSG; |
784 | } |
785 | |
786 | /* And of course validate what has just been read from the media */ |
787 | err = validate_ec_hdr(ubi, ec_hdr); |
788 | if (err) { |
789 | ubi_err(ubi, fmt: "validation failed for PEB %d" , pnum); |
790 | return -EINVAL; |
791 | } |
792 | |
793 | /* |
794 | * If there was %-EBADMSG, but the header CRC is still OK, report about |
795 | * a bit-flip to force scrubbing on this PEB. |
796 | */ |
797 | if (read_err) |
798 | return UBI_IO_BITFLIPS; |
799 | |
800 | if (ubi_dbg_is_read_failure(ubi, MASK_READ_FAILURE_EC)) { |
801 | ubi_warn(ubi, fmt: "cannot read EC header from PEB %d (emulated)" , |
802 | pnum); |
803 | return -EIO; |
804 | } |
805 | |
806 | if (ubi_dbg_is_ff(ubi, MASK_IO_FF_EC)) { |
807 | ubi_warn(ubi, fmt: "bit-all-ff (emulated)" ); |
808 | return UBI_IO_FF; |
809 | } |
810 | |
811 | if (ubi_dbg_is_ff_bitflips(ubi, MASK_IO_FF_BITFLIPS_EC)) { |
812 | ubi_warn(ubi, fmt: "bit-all-ff with error reported by MTD driver (emulated)" ); |
813 | return UBI_IO_FF_BITFLIPS; |
814 | } |
815 | |
816 | if (ubi_dbg_is_bad_hdr(ubi, MASK_BAD_HDR_EC)) { |
817 | ubi_warn(ubi, fmt: "bad_hdr (emulated)" ); |
818 | return UBI_IO_BAD_HDR; |
819 | } |
820 | |
821 | if (ubi_dbg_is_bad_hdr_ebadmsg(ubi, MASK_BAD_HDR_EBADMSG_EC)) { |
822 | ubi_warn(ubi, fmt: "bad_hdr with ECC error (emulated)" ); |
823 | return UBI_IO_BAD_HDR_EBADMSG; |
824 | } |
825 | |
826 | return 0; |
827 | } |
828 | |
829 | /** |
830 | * ubi_io_write_ec_hdr - write an erase counter header. |
831 | * @ubi: UBI device description object |
832 | * @pnum: physical eraseblock to write to |
833 | * @ec_hdr: the erase counter header to write |
834 | * |
835 | * This function writes erase counter header described by @ec_hdr to physical |
836 | * eraseblock @pnum. It also fills most fields of @ec_hdr before writing, so |
837 | * the caller do not have to fill them. Callers must only fill the @ec_hdr->ec |
838 | * field. |
839 | * |
840 | * This function returns zero in case of success and a negative error code in |
841 | * case of failure. If %-EIO is returned, the physical eraseblock most probably |
842 | * went bad. |
843 | */ |
844 | int ubi_io_write_ec_hdr(struct ubi_device *ubi, int pnum, |
845 | struct ubi_ec_hdr *ec_hdr) |
846 | { |
847 | int err; |
848 | uint32_t crc; |
849 | |
850 | dbg_io("write EC header to PEB %d" , pnum); |
851 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); |
852 | |
853 | ec_hdr->magic = cpu_to_be32(UBI_EC_HDR_MAGIC); |
854 | ec_hdr->version = UBI_VERSION; |
855 | ec_hdr->vid_hdr_offset = cpu_to_be32(ubi->vid_hdr_offset); |
856 | ec_hdr->data_offset = cpu_to_be32(ubi->leb_start); |
857 | ec_hdr->image_seq = cpu_to_be32(ubi->image_seq); |
858 | crc = crc32(UBI_CRC32_INIT, ec_hdr, UBI_EC_HDR_SIZE_CRC); |
859 | ec_hdr->hdr_crc = cpu_to_be32(crc); |
860 | |
861 | err = self_check_ec_hdr(ubi, pnum, ec_hdr); |
862 | if (err) |
863 | return err; |
864 | |
865 | if (ubi_dbg_is_power_cut(ubi, MASK_POWER_CUT_EC)) { |
866 | ubi_warn(ubi, fmt: "emulating a power cut when writing EC header" ); |
867 | ubi_ro_mode(ubi); |
868 | return -EROFS; |
869 | } |
870 | |
871 | err = ubi_io_write(ubi, buf: ec_hdr, pnum, offset: 0, len: ubi->ec_hdr_alsize); |
872 | return err; |
873 | } |
874 | |
875 | /** |
876 | * validate_vid_hdr - validate a volume identifier header. |
877 | * @ubi: UBI device description object |
878 | * @vid_hdr: the volume identifier header to check |
879 | * |
880 | * This function checks that data stored in the volume identifier header |
881 | * @vid_hdr. Returns zero if the VID header is OK and %1 if not. |
882 | */ |
883 | static int validate_vid_hdr(const struct ubi_device *ubi, |
884 | const struct ubi_vid_hdr *vid_hdr) |
885 | { |
886 | int vol_type = vid_hdr->vol_type; |
887 | int copy_flag = vid_hdr->copy_flag; |
888 | int vol_id = be32_to_cpu(vid_hdr->vol_id); |
889 | int lnum = be32_to_cpu(vid_hdr->lnum); |
890 | int compat = vid_hdr->compat; |
891 | int data_size = be32_to_cpu(vid_hdr->data_size); |
892 | int used_ebs = be32_to_cpu(vid_hdr->used_ebs); |
893 | int data_pad = be32_to_cpu(vid_hdr->data_pad); |
894 | int data_crc = be32_to_cpu(vid_hdr->data_crc); |
895 | int usable_leb_size = ubi->leb_size - data_pad; |
896 | |
897 | if (copy_flag != 0 && copy_flag != 1) { |
898 | ubi_err(ubi, fmt: "bad copy_flag" ); |
899 | goto bad; |
900 | } |
901 | |
902 | if (vol_id < 0 || lnum < 0 || data_size < 0 || used_ebs < 0 || |
903 | data_pad < 0) { |
904 | ubi_err(ubi, fmt: "negative values" ); |
905 | goto bad; |
906 | } |
907 | |
908 | if (vol_id >= UBI_MAX_VOLUMES && vol_id < UBI_INTERNAL_VOL_START) { |
909 | ubi_err(ubi, fmt: "bad vol_id" ); |
910 | goto bad; |
911 | } |
912 | |
913 | if (vol_id < UBI_INTERNAL_VOL_START && compat != 0) { |
914 | ubi_err(ubi, fmt: "bad compat" ); |
915 | goto bad; |
916 | } |
917 | |
918 | if (vol_id >= UBI_INTERNAL_VOL_START && compat != UBI_COMPAT_DELETE && |
919 | compat != UBI_COMPAT_RO && compat != UBI_COMPAT_PRESERVE && |
920 | compat != UBI_COMPAT_REJECT) { |
921 | ubi_err(ubi, fmt: "bad compat" ); |
922 | goto bad; |
923 | } |
924 | |
925 | if (vol_type != UBI_VID_DYNAMIC && vol_type != UBI_VID_STATIC) { |
926 | ubi_err(ubi, fmt: "bad vol_type" ); |
927 | goto bad; |
928 | } |
929 | |
930 | if (data_pad >= ubi->leb_size / 2) { |
931 | ubi_err(ubi, fmt: "bad data_pad" ); |
932 | goto bad; |
933 | } |
934 | |
935 | if (data_size > ubi->leb_size) { |
936 | ubi_err(ubi, fmt: "bad data_size" ); |
937 | goto bad; |
938 | } |
939 | |
940 | if (vol_type == UBI_VID_STATIC) { |
941 | /* |
942 | * Although from high-level point of view static volumes may |
943 | * contain zero bytes of data, but no VID headers can contain |
944 | * zero at these fields, because they empty volumes do not have |
945 | * mapped logical eraseblocks. |
946 | */ |
947 | if (used_ebs == 0) { |
948 | ubi_err(ubi, fmt: "zero used_ebs" ); |
949 | goto bad; |
950 | } |
951 | if (data_size == 0) { |
952 | ubi_err(ubi, fmt: "zero data_size" ); |
953 | goto bad; |
954 | } |
955 | if (lnum < used_ebs - 1) { |
956 | if (data_size != usable_leb_size) { |
957 | ubi_err(ubi, fmt: "bad data_size" ); |
958 | goto bad; |
959 | } |
960 | } else if (lnum > used_ebs - 1) { |
961 | ubi_err(ubi, fmt: "too high lnum" ); |
962 | goto bad; |
963 | } |
964 | } else { |
965 | if (copy_flag == 0) { |
966 | if (data_crc != 0) { |
967 | ubi_err(ubi, fmt: "non-zero data CRC" ); |
968 | goto bad; |
969 | } |
970 | if (data_size != 0) { |
971 | ubi_err(ubi, fmt: "non-zero data_size" ); |
972 | goto bad; |
973 | } |
974 | } else { |
975 | if (data_size == 0) { |
976 | ubi_err(ubi, fmt: "zero data_size of copy" ); |
977 | goto bad; |
978 | } |
979 | } |
980 | if (used_ebs != 0) { |
981 | ubi_err(ubi, fmt: "bad used_ebs" ); |
982 | goto bad; |
983 | } |
984 | } |
985 | |
986 | return 0; |
987 | |
988 | bad: |
989 | ubi_err(ubi, fmt: "bad VID header" ); |
990 | ubi_dump_vid_hdr(vid_hdr); |
991 | dump_stack(); |
992 | return 1; |
993 | } |
994 | |
995 | /** |
996 | * ubi_io_read_vid_hdr - read and check a volume identifier header. |
997 | * @ubi: UBI device description object |
998 | * @pnum: physical eraseblock number to read from |
999 | * @vidb: the volume identifier buffer to store data in |
1000 | * @verbose: be verbose if the header is corrupted or wasn't found |
1001 | * |
1002 | * This function reads the volume identifier header from physical eraseblock |
1003 | * @pnum and stores it in @vidb. It also checks CRC checksum of the read |
1004 | * volume identifier header. The error codes are the same as in |
1005 | * 'ubi_io_read_ec_hdr()'. |
1006 | * |
1007 | * Note, the implementation of this function is also very similar to |
1008 | * 'ubi_io_read_ec_hdr()', so refer commentaries in 'ubi_io_read_ec_hdr()'. |
1009 | */ |
1010 | int ubi_io_read_vid_hdr(struct ubi_device *ubi, int pnum, |
1011 | struct ubi_vid_io_buf *vidb, int verbose) |
1012 | { |
1013 | int err, read_err; |
1014 | uint32_t crc, magic, hdr_crc; |
1015 | struct ubi_vid_hdr *vid_hdr = ubi_get_vid_hdr(vidb); |
1016 | void *p = vidb->buffer; |
1017 | |
1018 | dbg_io("read VID header from PEB %d" , pnum); |
1019 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); |
1020 | |
1021 | read_err = ubi_io_read(ubi, buf: p, pnum, offset: ubi->vid_hdr_aloffset, |
1022 | len: ubi->vid_hdr_shift + UBI_VID_HDR_SIZE); |
1023 | if (read_err && read_err != UBI_IO_BITFLIPS && !mtd_is_eccerr(err: read_err)) |
1024 | return read_err; |
1025 | |
1026 | magic = be32_to_cpu(vid_hdr->magic); |
1027 | if (magic != UBI_VID_HDR_MAGIC) { |
1028 | if (mtd_is_eccerr(err: read_err)) |
1029 | return UBI_IO_BAD_HDR_EBADMSG; |
1030 | |
1031 | if (ubi_check_pattern(buf: vid_hdr, patt: 0xFF, UBI_VID_HDR_SIZE)) { |
1032 | if (verbose) |
1033 | ubi_warn(ubi, fmt: "no VID header found at PEB %d, only 0xFF bytes" , |
1034 | pnum); |
1035 | dbg_bld("no VID header found at PEB %d, only 0xFF bytes" , |
1036 | pnum); |
1037 | if (!read_err) |
1038 | return UBI_IO_FF; |
1039 | else |
1040 | return UBI_IO_FF_BITFLIPS; |
1041 | } |
1042 | |
1043 | if (verbose) { |
1044 | ubi_warn(ubi, fmt: "bad magic number at PEB %d: %08x instead of %08x" , |
1045 | pnum, magic, UBI_VID_HDR_MAGIC); |
1046 | ubi_dump_vid_hdr(vid_hdr); |
1047 | } |
1048 | dbg_bld("bad magic number at PEB %d: %08x instead of %08x" , |
1049 | pnum, magic, UBI_VID_HDR_MAGIC); |
1050 | return UBI_IO_BAD_HDR; |
1051 | } |
1052 | |
1053 | crc = crc32(UBI_CRC32_INIT, vid_hdr, UBI_VID_HDR_SIZE_CRC); |
1054 | hdr_crc = be32_to_cpu(vid_hdr->hdr_crc); |
1055 | |
1056 | if (hdr_crc != crc) { |
1057 | if (verbose) { |
1058 | ubi_warn(ubi, fmt: "bad CRC at PEB %d, calculated %#08x, read %#08x" , |
1059 | pnum, crc, hdr_crc); |
1060 | ubi_dump_vid_hdr(vid_hdr); |
1061 | } |
1062 | dbg_bld("bad CRC at PEB %d, calculated %#08x, read %#08x" , |
1063 | pnum, crc, hdr_crc); |
1064 | if (!read_err) |
1065 | return UBI_IO_BAD_HDR; |
1066 | else |
1067 | return UBI_IO_BAD_HDR_EBADMSG; |
1068 | } |
1069 | |
1070 | err = validate_vid_hdr(ubi, vid_hdr); |
1071 | if (err) { |
1072 | ubi_err(ubi, fmt: "validation failed for PEB %d" , pnum); |
1073 | return -EINVAL; |
1074 | } |
1075 | |
1076 | if (read_err) |
1077 | return UBI_IO_BITFLIPS; |
1078 | |
1079 | if (ubi_dbg_is_read_failure(ubi, MASK_READ_FAILURE_VID)) { |
1080 | ubi_warn(ubi, fmt: "cannot read VID header from PEB %d (emulated)" , |
1081 | pnum); |
1082 | return -EIO; |
1083 | } |
1084 | |
1085 | if (ubi_dbg_is_ff(ubi, MASK_IO_FF_VID)) { |
1086 | ubi_warn(ubi, fmt: "bit-all-ff (emulated)" ); |
1087 | return UBI_IO_FF; |
1088 | } |
1089 | |
1090 | if (ubi_dbg_is_ff_bitflips(ubi, MASK_IO_FF_BITFLIPS_VID)) { |
1091 | ubi_warn(ubi, fmt: "bit-all-ff with error reported by MTD driver (emulated)" ); |
1092 | return UBI_IO_FF_BITFLIPS; |
1093 | } |
1094 | |
1095 | if (ubi_dbg_is_bad_hdr(ubi, MASK_BAD_HDR_VID)) { |
1096 | ubi_warn(ubi, fmt: "bad_hdr (emulated)" ); |
1097 | return UBI_IO_BAD_HDR; |
1098 | } |
1099 | |
1100 | if (ubi_dbg_is_bad_hdr_ebadmsg(ubi, MASK_BAD_HDR_EBADMSG_VID)) { |
1101 | ubi_warn(ubi, fmt: "bad_hdr with ECC error (emulated)" ); |
1102 | return UBI_IO_BAD_HDR_EBADMSG; |
1103 | } |
1104 | |
1105 | return 0; |
1106 | } |
1107 | |
1108 | /** |
1109 | * ubi_io_write_vid_hdr - write a volume identifier header. |
1110 | * @ubi: UBI device description object |
1111 | * @pnum: the physical eraseblock number to write to |
1112 | * @vidb: the volume identifier buffer to write |
1113 | * |
1114 | * This function writes the volume identifier header described by @vid_hdr to |
1115 | * physical eraseblock @pnum. This function automatically fills the |
1116 | * @vidb->hdr->magic and the @vidb->hdr->version fields, as well as calculates |
1117 | * header CRC checksum and stores it at vidb->hdr->hdr_crc. |
1118 | * |
1119 | * This function returns zero in case of success and a negative error code in |
1120 | * case of failure. If %-EIO is returned, the physical eraseblock probably went |
1121 | * bad. |
1122 | */ |
1123 | int ubi_io_write_vid_hdr(struct ubi_device *ubi, int pnum, |
1124 | struct ubi_vid_io_buf *vidb) |
1125 | { |
1126 | struct ubi_vid_hdr *vid_hdr = ubi_get_vid_hdr(vidb); |
1127 | int err; |
1128 | uint32_t crc; |
1129 | void *p = vidb->buffer; |
1130 | |
1131 | dbg_io("write VID header to PEB %d" , pnum); |
1132 | ubi_assert(pnum >= 0 && pnum < ubi->peb_count); |
1133 | |
1134 | err = self_check_peb_ec_hdr(ubi, pnum); |
1135 | if (err) |
1136 | return err; |
1137 | |
1138 | vid_hdr->magic = cpu_to_be32(UBI_VID_HDR_MAGIC); |
1139 | vid_hdr->version = UBI_VERSION; |
1140 | crc = crc32(UBI_CRC32_INIT, vid_hdr, UBI_VID_HDR_SIZE_CRC); |
1141 | vid_hdr->hdr_crc = cpu_to_be32(crc); |
1142 | |
1143 | err = self_check_vid_hdr(ubi, pnum, vid_hdr); |
1144 | if (err) |
1145 | return err; |
1146 | |
1147 | if (ubi_dbg_is_power_cut(ubi, MASK_POWER_CUT_VID)) { |
1148 | ubi_warn(ubi, fmt: "emulating a power cut when writing VID header" ); |
1149 | ubi_ro_mode(ubi); |
1150 | return -EROFS; |
1151 | } |
1152 | |
1153 | err = ubi_io_write(ubi, buf: p, pnum, offset: ubi->vid_hdr_aloffset, |
1154 | len: ubi->vid_hdr_alsize); |
1155 | return err; |
1156 | } |
1157 | |
1158 | /** |
1159 | * self_check_not_bad - ensure that a physical eraseblock is not bad. |
1160 | * @ubi: UBI device description object |
1161 | * @pnum: physical eraseblock number to check |
1162 | * |
1163 | * This function returns zero if the physical eraseblock is good, %-EINVAL if |
1164 | * it is bad and a negative error code if an error occurred. |
1165 | */ |
1166 | static int self_check_not_bad(const struct ubi_device *ubi, int pnum) |
1167 | { |
1168 | int err; |
1169 | |
1170 | if (!ubi_dbg_chk_io(ubi)) |
1171 | return 0; |
1172 | |
1173 | err = ubi_io_is_bad(ubi, pnum); |
1174 | if (!err) |
1175 | return err; |
1176 | |
1177 | ubi_err(ubi, fmt: "self-check failed for PEB %d" , pnum); |
1178 | dump_stack(); |
1179 | return err > 0 ? -EINVAL : err; |
1180 | } |
1181 | |
1182 | /** |
1183 | * self_check_ec_hdr - check if an erase counter header is all right. |
1184 | * @ubi: UBI device description object |
1185 | * @pnum: physical eraseblock number the erase counter header belongs to |
1186 | * @ec_hdr: the erase counter header to check |
1187 | * |
1188 | * This function returns zero if the erase counter header contains valid |
1189 | * values, and %-EINVAL if not. |
1190 | */ |
1191 | static int self_check_ec_hdr(const struct ubi_device *ubi, int pnum, |
1192 | const struct ubi_ec_hdr *ec_hdr) |
1193 | { |
1194 | int err; |
1195 | uint32_t magic; |
1196 | |
1197 | if (!ubi_dbg_chk_io(ubi)) |
1198 | return 0; |
1199 | |
1200 | magic = be32_to_cpu(ec_hdr->magic); |
1201 | if (magic != UBI_EC_HDR_MAGIC) { |
1202 | ubi_err(ubi, fmt: "bad magic %#08x, must be %#08x" , |
1203 | magic, UBI_EC_HDR_MAGIC); |
1204 | goto fail; |
1205 | } |
1206 | |
1207 | err = validate_ec_hdr(ubi, ec_hdr); |
1208 | if (err) { |
1209 | ubi_err(ubi, fmt: "self-check failed for PEB %d" , pnum); |
1210 | goto fail; |
1211 | } |
1212 | |
1213 | return 0; |
1214 | |
1215 | fail: |
1216 | ubi_dump_ec_hdr(ec_hdr); |
1217 | dump_stack(); |
1218 | return -EINVAL; |
1219 | } |
1220 | |
1221 | /** |
1222 | * self_check_peb_ec_hdr - check erase counter header. |
1223 | * @ubi: UBI device description object |
1224 | * @pnum: the physical eraseblock number to check |
1225 | * |
1226 | * This function returns zero if the erase counter header is all right and |
1227 | * a negative error code if not or if an error occurred. |
1228 | */ |
1229 | static int self_check_peb_ec_hdr(const struct ubi_device *ubi, int pnum) |
1230 | { |
1231 | int err; |
1232 | uint32_t crc, hdr_crc; |
1233 | struct ubi_ec_hdr *ec_hdr; |
1234 | |
1235 | if (!ubi_dbg_chk_io(ubi)) |
1236 | return 0; |
1237 | |
1238 | ec_hdr = kzalloc(size: ubi->ec_hdr_alsize, GFP_NOFS); |
1239 | if (!ec_hdr) |
1240 | return -ENOMEM; |
1241 | |
1242 | err = ubi_io_read(ubi, buf: ec_hdr, pnum, offset: 0, UBI_EC_HDR_SIZE); |
1243 | if (err && err != UBI_IO_BITFLIPS && !mtd_is_eccerr(err)) |
1244 | goto exit; |
1245 | |
1246 | crc = crc32(UBI_CRC32_INIT, ec_hdr, UBI_EC_HDR_SIZE_CRC); |
1247 | hdr_crc = be32_to_cpu(ec_hdr->hdr_crc); |
1248 | if (hdr_crc != crc) { |
1249 | ubi_err(ubi, fmt: "bad CRC, calculated %#08x, read %#08x" , |
1250 | crc, hdr_crc); |
1251 | ubi_err(ubi, fmt: "self-check failed for PEB %d" , pnum); |
1252 | ubi_dump_ec_hdr(ec_hdr); |
1253 | dump_stack(); |
1254 | err = -EINVAL; |
1255 | goto exit; |
1256 | } |
1257 | |
1258 | err = self_check_ec_hdr(ubi, pnum, ec_hdr); |
1259 | |
1260 | exit: |
1261 | kfree(objp: ec_hdr); |
1262 | return err; |
1263 | } |
1264 | |
1265 | /** |
1266 | * self_check_vid_hdr - check that a volume identifier header is all right. |
1267 | * @ubi: UBI device description object |
1268 | * @pnum: physical eraseblock number the volume identifier header belongs to |
1269 | * @vid_hdr: the volume identifier header to check |
1270 | * |
1271 | * This function returns zero if the volume identifier header is all right, and |
1272 | * %-EINVAL if not. |
1273 | */ |
1274 | static int self_check_vid_hdr(const struct ubi_device *ubi, int pnum, |
1275 | const struct ubi_vid_hdr *vid_hdr) |
1276 | { |
1277 | int err; |
1278 | uint32_t magic; |
1279 | |
1280 | if (!ubi_dbg_chk_io(ubi)) |
1281 | return 0; |
1282 | |
1283 | magic = be32_to_cpu(vid_hdr->magic); |
1284 | if (magic != UBI_VID_HDR_MAGIC) { |
1285 | ubi_err(ubi, fmt: "bad VID header magic %#08x at PEB %d, must be %#08x" , |
1286 | magic, pnum, UBI_VID_HDR_MAGIC); |
1287 | goto fail; |
1288 | } |
1289 | |
1290 | err = validate_vid_hdr(ubi, vid_hdr); |
1291 | if (err) { |
1292 | ubi_err(ubi, fmt: "self-check failed for PEB %d" , pnum); |
1293 | goto fail; |
1294 | } |
1295 | |
1296 | return err; |
1297 | |
1298 | fail: |
1299 | ubi_err(ubi, fmt: "self-check failed for PEB %d" , pnum); |
1300 | ubi_dump_vid_hdr(vid_hdr); |
1301 | dump_stack(); |
1302 | return -EINVAL; |
1303 | |
1304 | } |
1305 | |
1306 | /** |
1307 | * self_check_peb_vid_hdr - check volume identifier header. |
1308 | * @ubi: UBI device description object |
1309 | * @pnum: the physical eraseblock number to check |
1310 | * |
1311 | * This function returns zero if the volume identifier header is all right, |
1312 | * and a negative error code if not or if an error occurred. |
1313 | */ |
1314 | static int self_check_peb_vid_hdr(const struct ubi_device *ubi, int pnum) |
1315 | { |
1316 | int err; |
1317 | uint32_t crc, hdr_crc; |
1318 | struct ubi_vid_io_buf *vidb; |
1319 | struct ubi_vid_hdr *vid_hdr; |
1320 | void *p; |
1321 | |
1322 | if (!ubi_dbg_chk_io(ubi)) |
1323 | return 0; |
1324 | |
1325 | vidb = ubi_alloc_vid_buf(ubi, GFP_NOFS); |
1326 | if (!vidb) |
1327 | return -ENOMEM; |
1328 | |
1329 | vid_hdr = ubi_get_vid_hdr(vidb); |
1330 | p = vidb->buffer; |
1331 | err = ubi_io_read(ubi, buf: p, pnum, offset: ubi->vid_hdr_aloffset, |
1332 | len: ubi->vid_hdr_alsize); |
1333 | if (err && err != UBI_IO_BITFLIPS && !mtd_is_eccerr(err)) |
1334 | goto exit; |
1335 | |
1336 | crc = crc32(UBI_CRC32_INIT, vid_hdr, UBI_VID_HDR_SIZE_CRC); |
1337 | hdr_crc = be32_to_cpu(vid_hdr->hdr_crc); |
1338 | if (hdr_crc != crc) { |
1339 | ubi_err(ubi, fmt: "bad VID header CRC at PEB %d, calculated %#08x, read %#08x" , |
1340 | pnum, crc, hdr_crc); |
1341 | ubi_err(ubi, fmt: "self-check failed for PEB %d" , pnum); |
1342 | ubi_dump_vid_hdr(vid_hdr); |
1343 | dump_stack(); |
1344 | err = -EINVAL; |
1345 | goto exit; |
1346 | } |
1347 | |
1348 | err = self_check_vid_hdr(ubi, pnum, vid_hdr); |
1349 | |
1350 | exit: |
1351 | ubi_free_vid_buf(vidb); |
1352 | return err; |
1353 | } |
1354 | |
1355 | /** |
1356 | * self_check_write - make sure write succeeded. |
1357 | * @ubi: UBI device description object |
1358 | * @buf: buffer with data which were written |
1359 | * @pnum: physical eraseblock number the data were written to |
1360 | * @offset: offset within the physical eraseblock the data were written to |
1361 | * @len: how many bytes were written |
1362 | * |
1363 | * This functions reads data which were recently written and compares it with |
1364 | * the original data buffer - the data have to match. Returns zero if the data |
1365 | * match and a negative error code if not or in case of failure. |
1366 | */ |
1367 | static int self_check_write(struct ubi_device *ubi, const void *buf, int pnum, |
1368 | int offset, int len) |
1369 | { |
1370 | int err, i; |
1371 | size_t read; |
1372 | void *buf1; |
1373 | loff_t addr = (loff_t)pnum * ubi->peb_size + offset; |
1374 | |
1375 | if (!ubi_dbg_chk_io(ubi)) |
1376 | return 0; |
1377 | |
1378 | buf1 = __vmalloc(size: len, GFP_NOFS); |
1379 | if (!buf1) { |
1380 | ubi_err(ubi, fmt: "cannot allocate memory to check writes" ); |
1381 | return 0; |
1382 | } |
1383 | |
1384 | err = mtd_read(mtd: ubi->mtd, from: addr, len, retlen: &read, buf: buf1); |
1385 | if (err && !mtd_is_bitflip(err)) |
1386 | goto out_free; |
1387 | |
1388 | for (i = 0; i < len; i++) { |
1389 | uint8_t c = ((uint8_t *)buf)[i]; |
1390 | uint8_t c1 = ((uint8_t *)buf1)[i]; |
1391 | int dump_len; |
1392 | |
1393 | if (c == c1) |
1394 | continue; |
1395 | |
1396 | ubi_err(ubi, fmt: "self-check failed for PEB %d:%d, len %d" , |
1397 | pnum, offset, len); |
1398 | ubi_msg(ubi, fmt: "data differ at position %d" , i); |
1399 | dump_len = max_t(int, 128, len - i); |
1400 | ubi_msg(ubi, fmt: "hex dump of the original buffer from %d to %d" , |
1401 | i, i + dump_len); |
1402 | print_hex_dump(KERN_DEBUG, prefix_str: "" , prefix_type: DUMP_PREFIX_OFFSET, rowsize: 32, groupsize: 1, |
1403 | buf: buf + i, len: dump_len, ascii: 1); |
1404 | ubi_msg(ubi, fmt: "hex dump of the read buffer from %d to %d" , |
1405 | i, i + dump_len); |
1406 | print_hex_dump(KERN_DEBUG, prefix_str: "" , prefix_type: DUMP_PREFIX_OFFSET, rowsize: 32, groupsize: 1, |
1407 | buf: buf1 + i, len: dump_len, ascii: 1); |
1408 | dump_stack(); |
1409 | err = -EINVAL; |
1410 | goto out_free; |
1411 | } |
1412 | |
1413 | vfree(addr: buf1); |
1414 | return 0; |
1415 | |
1416 | out_free: |
1417 | vfree(addr: buf1); |
1418 | return err; |
1419 | } |
1420 | |
1421 | /** |
1422 | * ubi_self_check_all_ff - check that a region of flash is empty. |
1423 | * @ubi: UBI device description object |
1424 | * @pnum: the physical eraseblock number to check |
1425 | * @offset: the starting offset within the physical eraseblock to check |
1426 | * @len: the length of the region to check |
1427 | * |
1428 | * This function returns zero if only 0xFF bytes are present at offset |
1429 | * @offset of the physical eraseblock @pnum, and a negative error code if not |
1430 | * or if an error occurred. |
1431 | */ |
1432 | int ubi_self_check_all_ff(struct ubi_device *ubi, int pnum, int offset, int len) |
1433 | { |
1434 | size_t read; |
1435 | int err; |
1436 | void *buf; |
1437 | loff_t addr = (loff_t)pnum * ubi->peb_size + offset; |
1438 | |
1439 | if (!ubi_dbg_chk_io(ubi)) |
1440 | return 0; |
1441 | |
1442 | buf = __vmalloc(size: len, GFP_NOFS); |
1443 | if (!buf) { |
1444 | ubi_err(ubi, fmt: "cannot allocate memory to check for 0xFFs" ); |
1445 | return 0; |
1446 | } |
1447 | |
1448 | err = mtd_read(mtd: ubi->mtd, from: addr, len, retlen: &read, buf); |
1449 | if (err && !mtd_is_bitflip(err)) { |
1450 | ubi_err(ubi, fmt: "err %d while reading %d bytes from PEB %d:%d, read %zd bytes" , |
1451 | err, len, pnum, offset, read); |
1452 | goto error; |
1453 | } |
1454 | |
1455 | err = ubi_check_pattern(buf, patt: 0xFF, size: len); |
1456 | if (err == 0) { |
1457 | ubi_err(ubi, fmt: "flash region at PEB %d:%d, length %d does not contain all 0xFF bytes" , |
1458 | pnum, offset, len); |
1459 | goto fail; |
1460 | } |
1461 | |
1462 | vfree(addr: buf); |
1463 | return 0; |
1464 | |
1465 | fail: |
1466 | ubi_err(ubi, fmt: "self-check failed for PEB %d" , pnum); |
1467 | ubi_msg(ubi, fmt: "hex dump of the %d-%d region" , offset, offset + len); |
1468 | print_hex_dump(KERN_DEBUG, prefix_str: "" , prefix_type: DUMP_PREFIX_OFFSET, rowsize: 32, groupsize: 1, buf, len, ascii: 1); |
1469 | err = -EINVAL; |
1470 | error: |
1471 | dump_stack(); |
1472 | vfree(addr: buf); |
1473 | return err; |
1474 | } |
1475 | |