2 * Copyright (c) International Business Machines Corp., 2006
3 * Copyright (c) Nokia Corporation, 2006, 2007
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.
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.
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
19 * Author: Artem Bityutskiy (Битюцкий Артём)
23 * UBI input/output sub-system.
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.
29 * We are trying to have a paranoid mindset and not to trust to what we read
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.
33 * Some words about how the eraseblock headers are stored.
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
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.
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
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
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?
66 * A: because when writing a sub-page, MTD still writes a full 2K page but the
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.
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.
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.
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.
89 #include <linux/crc32.h>
90 #include <linux/err.h>
91 #include <linux/slab.h>
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);
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
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
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
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);
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;
129 * o %-EIO if some I/O error occurred;
130 * o other negative error codes in case of other errors.
132 int ubi_io_read(const struct ubi_device *ubi, void *buf, int pnum, int offset,
135 int err, retries = 0;
139 dbg_io("read %d bytes from PEB %d:%d", len, pnum, offset);
141 ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
142 ubi_assert(offset >= 0 && offset + len <= ubi->peb_size);
145 err = paranoid_check_not_bad(ubi, pnum);
149 addr = (loff_t)pnum * ubi->peb_size + offset;
151 err = ubi->mtd->read(ubi->mtd, addr, len, &read, buf);
153 const char *errstr = (err == -EBADMSG) ? " (ECC error)" : "";
155 if (err == -EUCLEAN) {
157 * -EUCLEAN is reported if there was a bit-flip which
158 * was corrected, so this is harmless.
160 * We do not report about it here unless debugging is
161 * enabled. A corresponding message will be printed
162 * later, when it is has been scrubbed.
164 dbg_msg("fixable bit-flip detected at PEB %d", pnum);
165 ubi_assert(len == read);
166 return UBI_IO_BITFLIPS;
169 if (read != len && retries++ < UBI_IO_RETRIES) {
170 dbg_io("error %d%s while reading %d bytes from PEB %d:%d,"
171 " read only %zd bytes, retry",
172 err, errstr, len, pnum, offset, read);
177 ubi_err("error %d%s while reading %d bytes from PEB %d:%d, "
178 "read %zd bytes", err, errstr, len, pnum, offset, read);
179 ubi_dbg_dump_stack();
182 * The driver should never return -EBADMSG if it failed to read
183 * all the requested data. But some buggy drivers might do
184 * this, so we change it to -EIO.
186 if (read != len && err == -EBADMSG) {
191 ubi_assert(len == read);
193 if (ubi_dbg_is_bitflip()) {
194 dbg_gen("bit-flip (emulated)");
195 err = UBI_IO_BITFLIPS;
203 * ubi_io_write - write data to a physical eraseblock.
204 * @ubi: UBI device description object
205 * @buf: buffer with the data to write
206 * @pnum: physical eraseblock number to write to
207 * @offset: offset within the physical eraseblock where to write
208 * @len: how many bytes to write
210 * This function writes @len bytes of data from buffer @buf to offset @offset
211 * of physical eraseblock @pnum. If all the data were successfully written,
212 * zero is returned. If an error occurred, this function returns a negative
213 * error code. If %-EIO is returned, the physical eraseblock most probably went
216 * Note, in case of an error, it is possible that something was still written
217 * to the flash media, but may be some garbage.
219 int ubi_io_write(struct ubi_device *ubi, const void *buf, int pnum, int offset,
226 dbg_io("write %d bytes to PEB %d:%d", len, pnum, offset);
228 ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
229 ubi_assert(offset >= 0 && offset + len <= ubi->peb_size);
230 ubi_assert(offset % ubi->hdrs_min_io_size == 0);
231 ubi_assert(len > 0 && len % ubi->hdrs_min_io_size == 0);
234 ubi_err("read-only mode");
238 /* The below has to be compiled out if paranoid checks are disabled */
240 err = paranoid_check_not_bad(ubi, pnum);
244 /* The area we are writing to has to contain all 0xFF bytes */
245 err = ubi_dbg_check_all_ff(ubi, pnum, offset, len);
249 if (offset >= ubi->leb_start) {
251 * We write to the data area of the physical eraseblock. Make
252 * sure it has valid EC and VID headers.
254 err = paranoid_check_peb_ec_hdr(ubi, pnum);
257 err = paranoid_check_peb_vid_hdr(ubi, pnum);
262 if (ubi_dbg_is_write_failure()) {
263 dbg_err("cannot write %d bytes to PEB %d:%d "
264 "(emulated)", len, pnum, offset);
265 ubi_dbg_dump_stack();
269 addr = (loff_t)pnum * ubi->peb_size + offset;
270 err = ubi->mtd->write(ubi->mtd, addr, len, &written, buf);
272 ubi_err("error %d while writing %d bytes to PEB %d:%d, written "
273 "%zd bytes", err, len, pnum, offset, written);
274 ubi_dbg_dump_stack();
275 ubi_dbg_dump_flash(ubi, pnum, offset, len);
277 ubi_assert(written == len);
280 err = ubi_dbg_check_write(ubi, buf, pnum, offset, len);
285 * Since we always write sequentially, the rest of the PEB has
286 * to contain only 0xFF bytes.
289 len = ubi->peb_size - offset;
291 err = ubi_dbg_check_all_ff(ubi, pnum, offset, len);
298 * erase_callback - MTD erasure call-back.
299 * @ei: MTD erase information object.
301 * Note, even though MTD erase interface is asynchronous, all the current
302 * implementations are synchronous anyway.
304 static void erase_callback(struct erase_info *ei)
306 wake_up_interruptible((wait_queue_head_t *)ei->priv);
310 * do_sync_erase - synchronously erase a physical eraseblock.
311 * @ubi: UBI device description object
312 * @pnum: the physical eraseblock number to erase
314 * This function synchronously erases physical eraseblock @pnum and returns
315 * zero in case of success and a negative error code in case of failure. If
316 * %-EIO is returned, the physical eraseblock most probably went bad.
318 static int do_sync_erase(struct ubi_device *ubi, int pnum)
320 int err, retries = 0;
321 struct erase_info ei;
322 wait_queue_head_t wq;
324 dbg_io("erase PEB %d", pnum);
327 init_waitqueue_head(&wq);
328 memset(&ei, 0, sizeof(struct erase_info));
331 ei.addr = (loff_t)pnum * ubi->peb_size;
332 ei.len = ubi->peb_size;
333 ei.callback = erase_callback;
334 ei.priv = (unsigned long)&wq;
336 err = ubi->mtd->erase(ubi->mtd, &ei);
338 if (retries++ < UBI_IO_RETRIES) {
339 dbg_io("error %d while erasing PEB %d, retry",
344 ubi_err("cannot erase PEB %d, error %d", pnum, err);
345 ubi_dbg_dump_stack();
349 err = wait_event_interruptible(wq, ei.state == MTD_ERASE_DONE ||
350 ei.state == MTD_ERASE_FAILED);
352 ubi_err("interrupted PEB %d erasure", pnum);
356 if (ei.state == MTD_ERASE_FAILED) {
357 if (retries++ < UBI_IO_RETRIES) {
358 dbg_io("error while erasing PEB %d, retry", pnum);
362 ubi_err("cannot erase PEB %d", pnum);
363 ubi_dbg_dump_stack();
367 err = ubi_dbg_check_all_ff(ubi, pnum, 0, ubi->peb_size);
371 if (ubi_dbg_is_erase_failure() && !err) {
372 dbg_err("cannot erase PEB %d (emulated)", pnum);
379 /* Patterns to write to a physical eraseblock when torturing it */
380 static uint8_t patterns[] = {0xa5, 0x5a, 0x0};
383 * torture_peb - test a supposedly bad physical eraseblock.
384 * @ubi: UBI device description object
385 * @pnum: the physical eraseblock number to test
387 * This function returns %-EIO if the physical eraseblock did not pass the
388 * test, a positive number of erase operations done if the test was
389 * successfully passed, and other negative error codes in case of other errors.
391 static int torture_peb(struct ubi_device *ubi, int pnum)
393 int err, i, patt_count;
395 ubi_msg("run torture test for PEB %d", pnum);
396 patt_count = ARRAY_SIZE(patterns);
397 ubi_assert(patt_count > 0);
399 mutex_lock(&ubi->buf_mutex);
400 for (i = 0; i < patt_count; i++) {
401 err = do_sync_erase(ubi, pnum);
405 /* Make sure the PEB contains only 0xFF bytes */
406 err = ubi_io_read(ubi, ubi->peb_buf1, pnum, 0, ubi->peb_size);
410 err = ubi_check_pattern(ubi->peb_buf1, 0xFF, ubi->peb_size);
412 ubi_err("erased PEB %d, but a non-0xFF byte found",
418 /* Write a pattern and check it */
419 memset(ubi->peb_buf1, patterns[i], ubi->peb_size);
420 err = ubi_io_write(ubi, ubi->peb_buf1, pnum, 0, ubi->peb_size);
424 memset(ubi->peb_buf1, ~patterns[i], ubi->peb_size);
425 err = ubi_io_read(ubi, ubi->peb_buf1, pnum, 0, ubi->peb_size);
429 err = ubi_check_pattern(ubi->peb_buf1, patterns[i],
432 ubi_err("pattern %x checking failed for PEB %d",
440 ubi_msg("PEB %d passed torture test, do not mark it a bad", pnum);
443 mutex_unlock(&ubi->buf_mutex);
444 if (err == UBI_IO_BITFLIPS || err == -EBADMSG) {
446 * If a bit-flip or data integrity error was detected, the test
447 * has not passed because it happened on a freshly erased
448 * physical eraseblock which means something is wrong with it.
450 ubi_err("read problems on freshly erased PEB %d, must be bad",
458 * nor_erase_prepare - prepare a NOR flash PEB for erasure.
459 * @ubi: UBI device description object
460 * @pnum: physical eraseblock number to prepare
462 * NOR flash, or at least some of them, have peculiar embedded PEB erasure
463 * algorithm: the PEB is first filled with zeroes, then it is erased. And
464 * filling with zeroes starts from the end of the PEB. This was observed with
465 * Spansion S29GL512N NOR flash.
467 * This means that in case of a power cut we may end up with intact data at the
468 * beginning of the PEB, and all zeroes at the end of PEB. In other words, the
469 * EC and VID headers are OK, but a large chunk of data at the end of PEB is
470 * zeroed. This makes UBI mistakenly treat this PEB as used and associate it
471 * with an LEB, which leads to subsequent failures (e.g., UBIFS fails).
473 * This function is called before erasing NOR PEBs and it zeroes out EC and VID
474 * magic numbers in order to invalidate them and prevent the failures. Returns
475 * zero in case of success and a negative error code in case of failure.
477 static int nor_erase_prepare(struct ubi_device *ubi, int pnum)
483 struct ubi_vid_hdr vid_hdr;
486 * It is important to first invalidate the EC header, and then the VID
487 * header. Otherwise a power cut may lead to valid EC header and
488 * invalid VID header, in which case UBI will treat this PEB as
489 * corrupted and will try to preserve it, and print scary warnings (see
490 * the header comment in scan.c for more information).
492 addr = (loff_t)pnum * ubi->peb_size;
493 err = ubi->mtd->write(ubi->mtd, addr, 4, &written, (void *)&data);
495 addr += ubi->vid_hdr_aloffset;
496 err = ubi->mtd->write(ubi->mtd, addr, 4, &written,
503 * We failed to write to the media. This was observed with Spansion
504 * S29GL512N NOR flash. Most probably the previously eraseblock erasure
505 * was interrupted at a very inappropriate moment, so it became
506 * unwritable. In this case we probably anyway have garbage in this
509 err1 = ubi_io_read_vid_hdr(ubi, pnum, &vid_hdr, 0);
510 if (err1 == UBI_IO_BAD_HDR_EBADMSG || err1 == UBI_IO_BAD_HDR) {
511 struct ubi_ec_hdr ec_hdr;
513 err1 = ubi_io_read_ec_hdr(ubi, pnum, &ec_hdr, 0);
514 if (err1 == UBI_IO_BAD_HDR_EBADMSG || err1 == UBI_IO_BAD_HDR)
516 * Both VID and EC headers are corrupted, so we can
517 * safely erase this PEB and not afraid that it will be
518 * treated as a valid PEB in case of an unclean reboot.
524 * The PEB contains a valid VID header, but we cannot invalidate it.
525 * Supposedly the flash media or the driver is screwed up, so return an
528 ubi_err("cannot invalidate PEB %d, write returned %d read returned %d",
530 ubi_dbg_dump_flash(ubi, pnum, 0, ubi->peb_size);
535 * ubi_io_sync_erase - synchronously erase a physical eraseblock.
536 * @ubi: UBI device description object
537 * @pnum: physical eraseblock number to erase
538 * @torture: if this physical eraseblock has to be tortured
540 * This function synchronously erases physical eraseblock @pnum. If @torture
541 * flag is not zero, the physical eraseblock is checked by means of writing
542 * different patterns to it and reading them back. If the torturing is enabled,
543 * the physical eraseblock is erased more than once.
545 * This function returns the number of erasures made in case of success, %-EIO
546 * if the erasure failed or the torturing test failed, and other negative error
547 * codes in case of other errors. Note, %-EIO means that the physical
550 int ubi_io_sync_erase(struct ubi_device *ubi, int pnum, int torture)
554 ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
556 err = paranoid_check_not_bad(ubi, pnum);
561 ubi_err("read-only mode");
565 if (ubi->nor_flash) {
566 err = nor_erase_prepare(ubi, pnum);
572 ret = torture_peb(ubi, pnum);
577 err = do_sync_erase(ubi, pnum);
585 * ubi_io_is_bad - check if a physical eraseblock is bad.
586 * @ubi: UBI device description object
587 * @pnum: the physical eraseblock number to check
589 * This function returns a positive number if the physical eraseblock is bad,
590 * zero if not, and a negative error code if an error occurred.
592 int ubi_io_is_bad(const struct ubi_device *ubi, int pnum)
594 struct mtd_info *mtd = ubi->mtd;
596 ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
598 if (ubi->bad_allowed) {
601 ret = mtd->block_isbad(mtd, (loff_t)pnum * ubi->peb_size);
603 ubi_err("error %d while checking if PEB %d is bad",
606 dbg_io("PEB %d is bad", pnum);
614 * ubi_io_mark_bad - mark a physical eraseblock as bad.
615 * @ubi: UBI device description object
616 * @pnum: the physical eraseblock number to mark
618 * This function returns zero in case of success and a negative error code in
621 int ubi_io_mark_bad(const struct ubi_device *ubi, int pnum)
624 struct mtd_info *mtd = ubi->mtd;
626 ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
629 ubi_err("read-only mode");
633 if (!ubi->bad_allowed)
636 err = mtd->block_markbad(mtd, (loff_t)pnum * ubi->peb_size);
638 ubi_err("cannot mark PEB %d bad, error %d", pnum, err);
643 * validate_ec_hdr - validate an erase counter header.
644 * @ubi: UBI device description object
645 * @ec_hdr: the erase counter header to check
647 * This function returns zero if the erase counter header is OK, and %1 if
650 static int validate_ec_hdr(const struct ubi_device *ubi,
651 const struct ubi_ec_hdr *ec_hdr)
654 int vid_hdr_offset, leb_start;
656 ec = be64_to_cpu(ec_hdr->ec);
657 vid_hdr_offset = be32_to_cpu(ec_hdr->vid_hdr_offset);
658 leb_start = be32_to_cpu(ec_hdr->data_offset);
660 if (ec_hdr->version != UBI_VERSION) {
661 ubi_err("node with incompatible UBI version found: "
662 "this UBI version is %d, image version is %d",
663 UBI_VERSION, (int)ec_hdr->version);
667 if (vid_hdr_offset != ubi->vid_hdr_offset) {
668 ubi_err("bad VID header offset %d, expected %d",
669 vid_hdr_offset, ubi->vid_hdr_offset);
673 if (leb_start != ubi->leb_start) {
674 ubi_err("bad data offset %d, expected %d",
675 leb_start, ubi->leb_start);
679 if (ec < 0 || ec > UBI_MAX_ERASECOUNTER) {
680 ubi_err("bad erase counter %lld", ec);
687 ubi_err("bad EC header");
688 ubi_dbg_dump_ec_hdr(ec_hdr);
689 ubi_dbg_dump_stack();
694 * ubi_io_read_ec_hdr - read and check an erase counter header.
695 * @ubi: UBI device description object
696 * @pnum: physical eraseblock to read from
697 * @ec_hdr: a &struct ubi_ec_hdr object where to store the read erase counter
699 * @verbose: be verbose if the header is corrupted or was not found
701 * This function reads erase counter header from physical eraseblock @pnum and
702 * stores it in @ec_hdr. This function also checks CRC checksum of the read
703 * erase counter header. The following codes may be returned:
705 * o %0 if the CRC checksum is correct and the header was successfully read;
706 * o %UBI_IO_BITFLIPS if the CRC is correct, but bit-flips were detected
707 * and corrected by the flash driver; this is harmless but may indicate that
708 * this eraseblock may become bad soon (but may be not);
709 * o %UBI_IO_BAD_HDR if the erase counter header is corrupted (a CRC error);
710 * o %UBI_IO_BAD_HDR_EBADMSG is the same as %UBI_IO_BAD_HDR, but there also was
711 * a data integrity error (uncorrectable ECC error in case of NAND);
712 * o %UBI_IO_FF if only 0xFF bytes were read (the PEB is supposedly empty)
713 * o a negative error code in case of failure.
715 int ubi_io_read_ec_hdr(struct ubi_device *ubi, int pnum,
716 struct ubi_ec_hdr *ec_hdr, int verbose)
719 uint32_t crc, magic, hdr_crc;
721 dbg_io("read EC header from PEB %d", pnum);
722 ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
724 read_err = ubi_io_read(ubi, ec_hdr, pnum, 0, UBI_EC_HDR_SIZE);
726 if (read_err != UBI_IO_BITFLIPS && read_err != -EBADMSG)
730 * We read all the data, but either a correctable bit-flip
731 * occurred, or MTD reported a data integrity error
732 * (uncorrectable ECC error in case of NAND). The former is
733 * harmless, the later may mean that the read data is
734 * corrupted. But we have a CRC check-sum and we will detect
735 * this. If the EC header is still OK, we just report this as
736 * there was a bit-flip, to force scrubbing.
740 magic = be32_to_cpu(ec_hdr->magic);
741 if (magic != UBI_EC_HDR_MAGIC) {
742 if (read_err == -EBADMSG)
743 return UBI_IO_BAD_HDR_EBADMSG;
746 * The magic field is wrong. Let's check if we have read all
747 * 0xFF. If yes, this physical eraseblock is assumed to be
750 if (ubi_check_pattern(ec_hdr, 0xFF, UBI_EC_HDR_SIZE)) {
751 /* The physical eraseblock is supposedly empty */
753 ubi_warn("no EC header found at PEB %d, "
754 "only 0xFF bytes", pnum);
755 else if (UBI_IO_DEBUG)
756 dbg_msg("no EC header found at PEB %d, "
757 "only 0xFF bytes", pnum);
761 return UBI_IO_FF_BITFLIPS;
765 * This is not a valid erase counter header, and these are not
766 * 0xFF bytes. Report that the header is corrupted.
769 ubi_warn("bad magic number at PEB %d: %08x instead of "
770 "%08x", pnum, magic, UBI_EC_HDR_MAGIC);
771 ubi_dbg_dump_ec_hdr(ec_hdr);
772 } else if (UBI_IO_DEBUG)
773 dbg_msg("bad magic number at PEB %d: %08x instead of "
774 "%08x", pnum, magic, UBI_EC_HDR_MAGIC);
775 return UBI_IO_BAD_HDR;
778 crc = crc32(UBI_CRC32_INIT, ec_hdr, UBI_EC_HDR_SIZE_CRC);
779 hdr_crc = be32_to_cpu(ec_hdr->hdr_crc);
781 if (hdr_crc != crc) {
783 ubi_warn("bad EC header CRC at PEB %d, calculated "
784 "%#08x, read %#08x", pnum, crc, hdr_crc);
785 ubi_dbg_dump_ec_hdr(ec_hdr);
786 } else if (UBI_IO_DEBUG)
787 dbg_msg("bad EC header CRC at PEB %d, calculated "
788 "%#08x, read %#08x", pnum, crc, hdr_crc);
791 return UBI_IO_BAD_HDR;
793 return UBI_IO_BAD_HDR_EBADMSG;
796 /* And of course validate what has just been read from the media */
797 err = validate_ec_hdr(ubi, ec_hdr);
799 ubi_err("validation failed for PEB %d", pnum);
804 * If there was %-EBADMSG, but the header CRC is still OK, report about
805 * a bit-flip to force scrubbing on this PEB.
807 return read_err ? UBI_IO_BITFLIPS : 0;
811 * ubi_io_write_ec_hdr - write an erase counter header.
812 * @ubi: UBI device description object
813 * @pnum: physical eraseblock to write to
814 * @ec_hdr: the erase counter header to write
816 * This function writes erase counter header described by @ec_hdr to physical
817 * eraseblock @pnum. It also fills most fields of @ec_hdr before writing, so
818 * the caller do not have to fill them. Callers must only fill the @ec_hdr->ec
821 * This function returns zero in case of success and a negative error code in
822 * case of failure. If %-EIO is returned, the physical eraseblock most probably
825 int ubi_io_write_ec_hdr(struct ubi_device *ubi, int pnum,
826 struct ubi_ec_hdr *ec_hdr)
831 dbg_io("write EC header to PEB %d", pnum);
832 ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
834 ec_hdr->magic = cpu_to_be32(UBI_EC_HDR_MAGIC);
835 ec_hdr->version = UBI_VERSION;
836 ec_hdr->vid_hdr_offset = cpu_to_be32(ubi->vid_hdr_offset);
837 ec_hdr->data_offset = cpu_to_be32(ubi->leb_start);
838 ec_hdr->image_seq = cpu_to_be32(ubi->image_seq);
839 crc = crc32(UBI_CRC32_INIT, ec_hdr, UBI_EC_HDR_SIZE_CRC);
840 ec_hdr->hdr_crc = cpu_to_be32(crc);
842 err = paranoid_check_ec_hdr(ubi, pnum, ec_hdr);
846 err = ubi_io_write(ubi, ec_hdr, pnum, 0, ubi->ec_hdr_alsize);
851 * validate_vid_hdr - validate a volume identifier header.
852 * @ubi: UBI device description object
853 * @vid_hdr: the volume identifier header to check
855 * This function checks that data stored in the volume identifier header
856 * @vid_hdr. Returns zero if the VID header is OK and %1 if not.
858 static int validate_vid_hdr(const struct ubi_device *ubi,
859 const struct ubi_vid_hdr *vid_hdr)
861 int vol_type = vid_hdr->vol_type;
862 int copy_flag = vid_hdr->copy_flag;
863 int vol_id = be32_to_cpu(vid_hdr->vol_id);
864 int lnum = be32_to_cpu(vid_hdr->lnum);
865 int compat = vid_hdr->compat;
866 int data_size = be32_to_cpu(vid_hdr->data_size);
867 int used_ebs = be32_to_cpu(vid_hdr->used_ebs);
868 int data_pad = be32_to_cpu(vid_hdr->data_pad);
869 int data_crc = be32_to_cpu(vid_hdr->data_crc);
870 int usable_leb_size = ubi->leb_size - data_pad;
872 if (copy_flag != 0 && copy_flag != 1) {
873 dbg_err("bad copy_flag");
877 if (vol_id < 0 || lnum < 0 || data_size < 0 || used_ebs < 0 ||
879 dbg_err("negative values");
883 if (vol_id >= UBI_MAX_VOLUMES && vol_id < UBI_INTERNAL_VOL_START) {
884 dbg_err("bad vol_id");
888 if (vol_id < UBI_INTERNAL_VOL_START && compat != 0) {
889 dbg_err("bad compat");
893 if (vol_id >= UBI_INTERNAL_VOL_START && compat != UBI_COMPAT_DELETE &&
894 compat != UBI_COMPAT_RO && compat != UBI_COMPAT_PRESERVE &&
895 compat != UBI_COMPAT_REJECT) {
896 dbg_err("bad compat");
900 if (vol_type != UBI_VID_DYNAMIC && vol_type != UBI_VID_STATIC) {
901 dbg_err("bad vol_type");
905 if (data_pad >= ubi->leb_size / 2) {
906 dbg_err("bad data_pad");
910 if (vol_type == UBI_VID_STATIC) {
912 * Although from high-level point of view static volumes may
913 * contain zero bytes of data, but no VID headers can contain
914 * zero at these fields, because they empty volumes do not have
915 * mapped logical eraseblocks.
918 dbg_err("zero used_ebs");
921 if (data_size == 0) {
922 dbg_err("zero data_size");
925 if (lnum < used_ebs - 1) {
926 if (data_size != usable_leb_size) {
927 dbg_err("bad data_size");
930 } else if (lnum == used_ebs - 1) {
931 if (data_size == 0) {
932 dbg_err("bad data_size at last LEB");
936 dbg_err("too high lnum");
940 if (copy_flag == 0) {
942 dbg_err("non-zero data CRC");
945 if (data_size != 0) {
946 dbg_err("non-zero data_size");
950 if (data_size == 0) {
951 dbg_err("zero data_size of copy");
956 dbg_err("bad used_ebs");
964 ubi_err("bad VID header");
965 ubi_dbg_dump_vid_hdr(vid_hdr);
966 ubi_dbg_dump_stack();
971 * ubi_io_read_vid_hdr - read and check a volume identifier header.
972 * @ubi: UBI device description object
973 * @pnum: physical eraseblock number to read from
974 * @vid_hdr: &struct ubi_vid_hdr object where to store the read volume
976 * @verbose: be verbose if the header is corrupted or wasn't found
978 * This function reads the volume identifier header from physical eraseblock
979 * @pnum and stores it in @vid_hdr. It also checks CRC checksum of the read
980 * volume identifier header. The error codes are the same as in
981 * 'ubi_io_read_ec_hdr()'.
983 * Note, the implementation of this function is also very similar to
984 * 'ubi_io_read_ec_hdr()', so refer commentaries in 'ubi_io_read_ec_hdr()'.
986 int ubi_io_read_vid_hdr(struct ubi_device *ubi, int pnum,
987 struct ubi_vid_hdr *vid_hdr, int verbose)
990 uint32_t crc, magic, hdr_crc;
993 dbg_io("read VID header from PEB %d", pnum);
994 ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
996 p = (char *)vid_hdr - ubi->vid_hdr_shift;
997 read_err = ubi_io_read(ubi, p, pnum, ubi->vid_hdr_aloffset,
998 ubi->vid_hdr_alsize);
999 if (read_err && read_err != UBI_IO_BITFLIPS && read_err != -EBADMSG)
1002 magic = be32_to_cpu(vid_hdr->magic);
1003 if (magic != UBI_VID_HDR_MAGIC) {
1004 if (read_err == -EBADMSG)
1005 return UBI_IO_BAD_HDR_EBADMSG;
1007 if (ubi_check_pattern(vid_hdr, 0xFF, UBI_VID_HDR_SIZE)) {
1009 ubi_warn("no VID header found at PEB %d, "
1010 "only 0xFF bytes", pnum);
1011 else if (UBI_IO_DEBUG)
1012 dbg_msg("no VID header found at PEB %d, "
1013 "only 0xFF bytes", pnum);
1017 return UBI_IO_FF_BITFLIPS;
1021 ubi_warn("bad magic number at PEB %d: %08x instead of "
1022 "%08x", pnum, magic, UBI_VID_HDR_MAGIC);
1023 ubi_dbg_dump_vid_hdr(vid_hdr);
1024 } else if (UBI_IO_DEBUG)
1025 dbg_msg("bad magic number at PEB %d: %08x instead of "
1026 "%08x", pnum, magic, UBI_VID_HDR_MAGIC);
1027 return UBI_IO_BAD_HDR;
1030 crc = crc32(UBI_CRC32_INIT, vid_hdr, UBI_VID_HDR_SIZE_CRC);
1031 hdr_crc = be32_to_cpu(vid_hdr->hdr_crc);
1033 if (hdr_crc != crc) {
1035 ubi_warn("bad CRC at PEB %d, calculated %#08x, "
1036 "read %#08x", pnum, crc, hdr_crc);
1037 ubi_dbg_dump_vid_hdr(vid_hdr);
1038 } else if (UBI_IO_DEBUG)
1039 dbg_msg("bad CRC at PEB %d, calculated %#08x, "
1040 "read %#08x", pnum, crc, hdr_crc);
1042 return UBI_IO_BAD_HDR;
1044 return UBI_IO_BAD_HDR_EBADMSG;
1047 err = validate_vid_hdr(ubi, vid_hdr);
1049 ubi_err("validation failed for PEB %d", pnum);
1053 return read_err ? UBI_IO_BITFLIPS : 0;
1057 * ubi_io_write_vid_hdr - write a volume identifier header.
1058 * @ubi: UBI device description object
1059 * @pnum: the physical eraseblock number to write to
1060 * @vid_hdr: the volume identifier header to write
1062 * This function writes the volume identifier header described by @vid_hdr to
1063 * physical eraseblock @pnum. This function automatically fills the
1064 * @vid_hdr->magic and the @vid_hdr->version fields, as well as calculates
1065 * header CRC checksum and stores it at vid_hdr->hdr_crc.
1067 * This function returns zero in case of success and a negative error code in
1068 * case of failure. If %-EIO is returned, the physical eraseblock probably went
1071 int ubi_io_write_vid_hdr(struct ubi_device *ubi, int pnum,
1072 struct ubi_vid_hdr *vid_hdr)
1078 dbg_io("write VID header to PEB %d", pnum);
1079 ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
1081 err = paranoid_check_peb_ec_hdr(ubi, pnum);
1085 vid_hdr->magic = cpu_to_be32(UBI_VID_HDR_MAGIC);
1086 vid_hdr->version = UBI_VERSION;
1087 crc = crc32(UBI_CRC32_INIT, vid_hdr, UBI_VID_HDR_SIZE_CRC);
1088 vid_hdr->hdr_crc = cpu_to_be32(crc);
1090 err = paranoid_check_vid_hdr(ubi, pnum, vid_hdr);
1094 p = (char *)vid_hdr - ubi->vid_hdr_shift;
1095 err = ubi_io_write(ubi, p, pnum, ubi->vid_hdr_aloffset,
1096 ubi->vid_hdr_alsize);
1100 #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
1103 * paranoid_check_not_bad - ensure that a physical eraseblock is not bad.
1104 * @ubi: UBI device description object
1105 * @pnum: physical eraseblock number to check
1107 * This function returns zero if the physical eraseblock is good, %-EINVAL if
1108 * it is bad and a negative error code if an error occurred.
1110 static int paranoid_check_not_bad(const struct ubi_device *ubi, int pnum)
1114 err = ubi_io_is_bad(ubi, pnum);
1118 ubi_err("paranoid check failed for PEB %d", pnum);
1119 ubi_dbg_dump_stack();
1120 return err > 0 ? -EINVAL : err;
1124 * paranoid_check_ec_hdr - check if an erase counter header is all right.
1125 * @ubi: UBI device description object
1126 * @pnum: physical eraseblock number the erase counter header belongs to
1127 * @ec_hdr: the erase counter header to check
1129 * This function returns zero if the erase counter header contains valid
1130 * values, and %-EINVAL if not.
1132 static int paranoid_check_ec_hdr(const struct ubi_device *ubi, int pnum,
1133 const struct ubi_ec_hdr *ec_hdr)
1138 magic = be32_to_cpu(ec_hdr->magic);
1139 if (magic != UBI_EC_HDR_MAGIC) {
1140 ubi_err("bad magic %#08x, must be %#08x",
1141 magic, UBI_EC_HDR_MAGIC);
1145 err = validate_ec_hdr(ubi, ec_hdr);
1147 ubi_err("paranoid check failed for PEB %d", pnum);
1154 ubi_dbg_dump_ec_hdr(ec_hdr);
1155 ubi_dbg_dump_stack();
1160 * paranoid_check_peb_ec_hdr - check erase counter header.
1161 * @ubi: UBI device description object
1162 * @pnum: the physical eraseblock number to check
1164 * This function returns zero if the erase counter header is all right and and
1165 * a negative error code if not or if an error occurred.
1167 static int paranoid_check_peb_ec_hdr(const struct ubi_device *ubi, int pnum)
1170 uint32_t crc, hdr_crc;
1171 struct ubi_ec_hdr *ec_hdr;
1173 ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_NOFS);
1177 err = ubi_io_read(ubi, ec_hdr, pnum, 0, UBI_EC_HDR_SIZE);
1178 if (err && err != UBI_IO_BITFLIPS && err != -EBADMSG)
1181 crc = crc32(UBI_CRC32_INIT, ec_hdr, UBI_EC_HDR_SIZE_CRC);
1182 hdr_crc = be32_to_cpu(ec_hdr->hdr_crc);
1183 if (hdr_crc != crc) {
1184 ubi_err("bad CRC, calculated %#08x, read %#08x", crc, hdr_crc);
1185 ubi_err("paranoid check failed for PEB %d", pnum);
1186 ubi_dbg_dump_ec_hdr(ec_hdr);
1187 ubi_dbg_dump_stack();
1192 err = paranoid_check_ec_hdr(ubi, pnum, ec_hdr);
1200 * paranoid_check_vid_hdr - check that a volume identifier header is all right.
1201 * @ubi: UBI device description object
1202 * @pnum: physical eraseblock number the volume identifier header belongs to
1203 * @vid_hdr: the volume identifier header to check
1205 * This function returns zero if the volume identifier header is all right, and
1208 static int paranoid_check_vid_hdr(const struct ubi_device *ubi, int pnum,
1209 const struct ubi_vid_hdr *vid_hdr)
1214 magic = be32_to_cpu(vid_hdr->magic);
1215 if (magic != UBI_VID_HDR_MAGIC) {
1216 ubi_err("bad VID header magic %#08x at PEB %d, must be %#08x",
1217 magic, pnum, UBI_VID_HDR_MAGIC);
1221 err = validate_vid_hdr(ubi, vid_hdr);
1223 ubi_err("paranoid check failed for PEB %d", pnum);
1230 ubi_err("paranoid check failed for PEB %d", pnum);
1231 ubi_dbg_dump_vid_hdr(vid_hdr);
1232 ubi_dbg_dump_stack();
1238 * paranoid_check_peb_vid_hdr - check volume identifier header.
1239 * @ubi: UBI device description object
1240 * @pnum: the physical eraseblock number to check
1242 * This function returns zero if the volume identifier header is all right,
1243 * and a negative error code if not or if an error occurred.
1245 static int paranoid_check_peb_vid_hdr(const struct ubi_device *ubi, int pnum)
1248 uint32_t crc, hdr_crc;
1249 struct ubi_vid_hdr *vid_hdr;
1252 vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS);
1256 p = (char *)vid_hdr - ubi->vid_hdr_shift;
1257 err = ubi_io_read(ubi, p, pnum, ubi->vid_hdr_aloffset,
1258 ubi->vid_hdr_alsize);
1259 if (err && err != UBI_IO_BITFLIPS && err != -EBADMSG)
1262 crc = crc32(UBI_CRC32_INIT, vid_hdr, UBI_EC_HDR_SIZE_CRC);
1263 hdr_crc = be32_to_cpu(vid_hdr->hdr_crc);
1264 if (hdr_crc != crc) {
1265 ubi_err("bad VID header CRC at PEB %d, calculated %#08x, "
1266 "read %#08x", pnum, crc, hdr_crc);
1267 ubi_err("paranoid check failed for PEB %d", pnum);
1268 ubi_dbg_dump_vid_hdr(vid_hdr);
1269 ubi_dbg_dump_stack();
1274 err = paranoid_check_vid_hdr(ubi, pnum, vid_hdr);
1277 ubi_free_vid_hdr(ubi, vid_hdr);
1282 * ubi_dbg_check_write - make sure write succeeded.
1283 * @ubi: UBI device description object
1284 * @buf: buffer with data which were written
1285 * @pnum: physical eraseblock number the data were written to
1286 * @offset: offset within the physical eraseblock the data were written to
1287 * @len: how many bytes were written
1289 * This functions reads data which were recently written and compares it with
1290 * the original data buffer - the data have to match. Returns zero if the data
1291 * match and a negative error code if not or in case of failure.
1293 int ubi_dbg_check_write(struct ubi_device *ubi, const void *buf, int pnum,
1294 int offset, int len)
1298 mutex_lock(&ubi->dbg_buf_mutex);
1299 err = ubi_io_read(ubi, ubi->dbg_peb_buf, pnum, offset, len);
1303 for (i = 0; i < len; i++) {
1304 uint8_t c = ((uint8_t *)buf)[i];
1305 uint8_t c1 = ((uint8_t *)ubi->dbg_peb_buf)[i];
1311 ubi_err("paranoid check failed for PEB %d:%d, len %d",
1313 ubi_msg("data differ at position %d", i);
1314 dump_len = max_t(int, 128, len - i);
1315 ubi_msg("hex dump of the original buffer from %d to %d",
1317 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1,
1318 buf + i, dump_len, 1);
1319 ubi_msg("hex dump of the read buffer from %d to %d",
1321 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1,
1322 ubi->dbg_peb_buf + i, dump_len, 1);
1323 ubi_dbg_dump_stack();
1327 mutex_unlock(&ubi->dbg_buf_mutex);
1332 mutex_unlock(&ubi->dbg_buf_mutex);
1337 * ubi_dbg_check_all_ff - check that a region of flash is empty.
1338 * @ubi: UBI device description object
1339 * @pnum: the physical eraseblock number to check
1340 * @offset: the starting offset within the physical eraseblock to check
1341 * @len: the length of the region to check
1343 * This function returns zero if only 0xFF bytes are present at offset
1344 * @offset of the physical eraseblock @pnum, and a negative error code if not
1345 * or if an error occurred.
1347 int ubi_dbg_check_all_ff(struct ubi_device *ubi, int pnum, int offset, int len)
1351 loff_t addr = (loff_t)pnum * ubi->peb_size + offset;
1353 mutex_lock(&ubi->dbg_buf_mutex);
1354 err = ubi->mtd->read(ubi->mtd, addr, len, &read, ubi->dbg_peb_buf);
1355 if (err && err != -EUCLEAN) {
1356 ubi_err("error %d while reading %d bytes from PEB %d:%d, "
1357 "read %zd bytes", err, len, pnum, offset, read);
1361 err = ubi_check_pattern(ubi->dbg_peb_buf, 0xFF, len);
1363 ubi_err("flash region at PEB %d:%d, length %d does not "
1364 "contain all 0xFF bytes", pnum, offset, len);
1367 mutex_unlock(&ubi->dbg_buf_mutex);
1372 ubi_err("paranoid check failed for PEB %d", pnum);
1373 ubi_msg("hex dump of the %d-%d region", offset, offset + len);
1374 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1,
1375 ubi->dbg_peb_buf, len, 1);
1378 ubi_dbg_dump_stack();
1379 mutex_unlock(&ubi->dbg_buf_mutex);
1383 #endif /* CONFIG_MTD_UBI_DEBUG_PARANOID */