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 static int self_check_not_bad(const struct ubi_device
*ubi
, int pnum
);
95 static int self_check_peb_ec_hdr(const struct ubi_device
*ubi
, int pnum
);
96 static int self_check_ec_hdr(const struct ubi_device
*ubi
, int pnum
,
97 const struct ubi_ec_hdr
*ec_hdr
);
98 static int self_check_peb_vid_hdr(const struct ubi_device
*ubi
, int pnum
);
99 static int self_check_vid_hdr(const struct ubi_device
*ubi
, int pnum
,
100 const struct ubi_vid_hdr
*vid_hdr
);
101 static int self_check_write(struct ubi_device
*ubi
, const void *buf
, int pnum
,
102 int offset
, int len
);
105 * ubi_io_read - read data from a physical eraseblock.
106 * @ubi: UBI device description object
107 * @buf: buffer where to store the read data
108 * @pnum: physical eraseblock number to read from
109 * @offset: offset within the physical eraseblock from where to read
110 * @len: how many bytes to read
112 * This function reads data from offset @offset of physical eraseblock @pnum
113 * and stores the read data in the @buf buffer. The following return codes are
116 * o %0 if all the requested data were successfully read;
117 * o %UBI_IO_BITFLIPS if all the requested data were successfully read, but
118 * correctable bit-flips were detected; this is harmless but may indicate
119 * that this eraseblock may become bad soon (but do not have to);
120 * o %-EBADMSG if the MTD subsystem reported about data integrity problems, for
121 * example it can be an ECC error in case of NAND; this most probably means
122 * that the data is corrupted;
123 * o %-EIO if some I/O error occurred;
124 * o other negative error codes in case of other errors.
126 int ubi_io_read(const struct ubi_device
*ubi
, void *buf
, int pnum
, int offset
,
129 int err
, retries
= 0;
133 dbg_io("read %d bytes from PEB %d:%d", len
, pnum
, offset
);
135 ubi_assert(pnum
>= 0 && pnum
< ubi
->peb_count
);
136 ubi_assert(offset
>= 0 && offset
+ len
<= ubi
->peb_size
);
139 err
= self_check_not_bad(ubi
, pnum
);
144 * Deliberately corrupt the buffer to improve robustness. Indeed, if we
145 * do not do this, the following may happen:
146 * 1. The buffer contains data from previous operation, e.g., read from
147 * another PEB previously. The data looks like expected, e.g., if we
148 * just do not read anything and return - the caller would not
149 * notice this. E.g., if we are reading a VID header, the buffer may
150 * contain a valid VID header from another PEB.
151 * 2. The driver is buggy and returns us success or -EBADMSG or
152 * -EUCLEAN, but it does not actually put any data to the buffer.
154 * This may confuse UBI or upper layers - they may think the buffer
155 * contains valid data while in fact it is just old data. This is
156 * especially possible because UBI (and UBIFS) relies on CRC, and
157 * treats data as correct even in case of ECC errors if the CRC is
160 * Try to prevent this situation by changing the first byte of the
163 *((uint8_t *)buf
) ^= 0xFF;
165 addr
= (loff_t
)pnum
* ubi
->peb_size
+ offset
;
167 err
= mtd_read(ubi
->mtd
, addr
, len
, &read
, buf
);
169 const char *errstr
= mtd_is_eccerr(err
) ? " (ECC error)" : "";
171 if (mtd_is_bitflip(err
)) {
173 * -EUCLEAN is reported if there was a bit-flip which
174 * was corrected, so this is harmless.
176 * We do not report about it here unless debugging is
177 * enabled. A corresponding message will be printed
178 * later, when it is has been scrubbed.
180 ubi_msg("fixable bit-flip detected at PEB %d", pnum
);
181 ubi_assert(len
== read
);
182 return UBI_IO_BITFLIPS
;
185 if (retries
++ < UBI_IO_RETRIES
) {
186 ubi_warn("error %d%s while reading %d bytes from PEB %d:%d, read only %zd bytes, retry",
187 err
, errstr
, len
, pnum
, offset
, read
);
192 ubi_err("error %d%s while reading %d bytes from PEB %d:%d, read %zd bytes",
193 err
, errstr
, len
, pnum
, offset
, read
);
197 * The driver should never return -EBADMSG if it failed to read
198 * all the requested data. But some buggy drivers might do
199 * this, so we change it to -EIO.
201 if (read
!= len
&& mtd_is_eccerr(err
)) {
206 ubi_assert(len
== read
);
208 if (ubi_dbg_is_bitflip(ubi
)) {
209 dbg_gen("bit-flip (emulated)");
210 err
= UBI_IO_BITFLIPS
;
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
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
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.
234 int ubi_io_write(struct ubi_device
*ubi
, const void *buf
, int pnum
, int offset
,
241 dbg_io("write %d bytes to PEB %d:%d", len
, pnum
, offset
);
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);
249 ubi_err("read-only mode");
253 err
= self_check_not_bad(ubi
, pnum
);
257 /* The area we are writing to has to contain all 0xFF bytes */
258 err
= ubi_self_check_all_ff(ubi
, pnum
, offset
, len
);
262 if (offset
>= ubi
->leb_start
) {
264 * We write to the data area of the physical eraseblock. Make
265 * sure it has valid EC and VID headers.
267 err
= self_check_peb_ec_hdr(ubi
, pnum
);
270 err
= self_check_peb_vid_hdr(ubi
, pnum
);
275 if (ubi_dbg_is_write_failure(ubi
)) {
276 ubi_err("cannot write %d bytes to PEB %d:%d (emulated)",
282 addr
= (loff_t
)pnum
* ubi
->peb_size
+ offset
;
283 err
= mtd_write(ubi
->mtd
, addr
, len
, &written
, buf
);
285 ubi_err("error %d while writing %d bytes to PEB %d:%d, written %zd bytes",
286 err
, len
, pnum
, offset
, written
);
288 ubi_dump_flash(ubi
, pnum
, offset
, len
);
290 ubi_assert(written
== len
);
293 err
= self_check_write(ubi
, buf
, pnum
, offset
, len
);
298 * Since we always write sequentially, the rest of the PEB has
299 * to contain only 0xFF bytes.
302 len
= ubi
->peb_size
- offset
;
304 err
= ubi_self_check_all_ff(ubi
, pnum
, offset
, len
);
311 * erase_callback - MTD erasure call-back.
312 * @ei: MTD erase information object.
314 * Note, even though MTD erase interface is asynchronous, all the current
315 * implementations are synchronous anyway.
317 static void erase_callback(struct erase_info
*ei
)
319 wake_up_interruptible((wait_queue_head_t
*)ei
->priv
);
323 * do_sync_erase - synchronously erase a physical eraseblock.
324 * @ubi: UBI device description object
325 * @pnum: the physical eraseblock number to erase
327 * This function synchronously erases physical eraseblock @pnum and returns
328 * zero in case of success and a negative error code in case of failure. If
329 * %-EIO is returned, the physical eraseblock most probably went bad.
331 static int do_sync_erase(struct ubi_device
*ubi
, int pnum
)
333 int err
, retries
= 0;
334 struct erase_info ei
;
335 wait_queue_head_t wq
;
337 dbg_io("erase PEB %d", pnum
);
338 ubi_assert(pnum
>= 0 && pnum
< ubi
->peb_count
);
341 ubi_err("read-only mode");
346 init_waitqueue_head(&wq
);
347 memset(&ei
, 0, sizeof(struct erase_info
));
350 ei
.addr
= (loff_t
)pnum
* ubi
->peb_size
;
351 ei
.len
= ubi
->peb_size
;
352 ei
.callback
= erase_callback
;
353 ei
.priv
= (unsigned long)&wq
;
355 err
= mtd_erase(ubi
->mtd
, &ei
);
357 if (retries
++ < UBI_IO_RETRIES
) {
358 ubi_warn("error %d while erasing PEB %d, retry",
363 ubi_err("cannot erase PEB %d, error %d", pnum
, err
);
368 err
= wait_event_interruptible(wq
, ei
.state
== MTD_ERASE_DONE
||
369 ei
.state
== MTD_ERASE_FAILED
);
371 ubi_err("interrupted PEB %d erasure", pnum
);
375 if (ei
.state
== MTD_ERASE_FAILED
) {
376 if (retries
++ < UBI_IO_RETRIES
) {
377 ubi_warn("error while erasing PEB %d, retry", pnum
);
381 ubi_err("cannot erase PEB %d", pnum
);
386 err
= ubi_self_check_all_ff(ubi
, pnum
, 0, ubi
->peb_size
);
390 if (ubi_dbg_is_erase_failure(ubi
)) {
391 ubi_err("cannot erase PEB %d (emulated)", pnum
);
398 /* Patterns to write to a physical eraseblock when torturing it */
399 static uint8_t patterns
[] = {0xa5, 0x5a, 0x0};
402 * torture_peb - test a supposedly bad physical eraseblock.
403 * @ubi: UBI device description object
404 * @pnum: the physical eraseblock number to test
406 * This function returns %-EIO if the physical eraseblock did not pass the
407 * test, a positive number of erase operations done if the test was
408 * successfully passed, and other negative error codes in case of other errors.
410 static int torture_peb(struct ubi_device
*ubi
, int pnum
)
412 int err
, i
, patt_count
;
414 ubi_msg("run torture test for PEB %d", pnum
);
415 patt_count
= ARRAY_SIZE(patterns
);
416 ubi_assert(patt_count
> 0);
418 mutex_lock(&ubi
->buf_mutex
);
419 for (i
= 0; i
< patt_count
; i
++) {
420 err
= do_sync_erase(ubi
, pnum
);
424 /* Make sure the PEB contains only 0xFF bytes */
425 err
= ubi_io_read(ubi
, ubi
->peb_buf
, pnum
, 0, ubi
->peb_size
);
429 err
= ubi_check_pattern(ubi
->peb_buf
, 0xFF, ubi
->peb_size
);
431 ubi_err("erased PEB %d, but a non-0xFF byte found",
437 /* Write a pattern and check it */
438 memset(ubi
->peb_buf
, patterns
[i
], ubi
->peb_size
);
439 err
= ubi_io_write(ubi
, ubi
->peb_buf
, pnum
, 0, ubi
->peb_size
);
443 memset(ubi
->peb_buf
, ~patterns
[i
], ubi
->peb_size
);
444 err
= ubi_io_read(ubi
, ubi
->peb_buf
, pnum
, 0, ubi
->peb_size
);
448 err
= ubi_check_pattern(ubi
->peb_buf
, patterns
[i
],
451 ubi_err("pattern %x checking failed for PEB %d",
459 ubi_msg("PEB %d passed torture test, do not mark it as bad", pnum
);
462 mutex_unlock(&ubi
->buf_mutex
);
463 if (err
== UBI_IO_BITFLIPS
|| mtd_is_eccerr(err
)) {
465 * If a bit-flip or data integrity error was detected, the test
466 * has not passed because it happened on a freshly erased
467 * physical eraseblock which means something is wrong with it.
469 ubi_err("read problems on freshly erased PEB %d, must be bad",
477 * nor_erase_prepare - prepare a NOR flash PEB for erasure.
478 * @ubi: UBI device description object
479 * @pnum: physical eraseblock number to prepare
481 * NOR flash, or at least some of them, have peculiar embedded PEB erasure
482 * algorithm: the PEB is first filled with zeroes, then it is erased. And
483 * filling with zeroes starts from the end of the PEB. This was observed with
484 * Spansion S29GL512N NOR flash.
486 * This means that in case of a power cut we may end up with intact data at the
487 * beginning of the PEB, and all zeroes at the end of PEB. In other words, the
488 * EC and VID headers are OK, but a large chunk of data at the end of PEB is
489 * zeroed. This makes UBI mistakenly treat this PEB as used and associate it
490 * with an LEB, which leads to subsequent failures (e.g., UBIFS fails).
492 * This function is called before erasing NOR PEBs and it zeroes out EC and VID
493 * magic numbers in order to invalidate them and prevent the failures. Returns
494 * zero in case of success and a negative error code in case of failure.
496 static int nor_erase_prepare(struct ubi_device
*ubi
, int pnum
)
502 struct ubi_ec_hdr ec_hdr
;
505 * Note, we cannot generally define VID header buffers on stack,
506 * because of the way we deal with these buffers (see the header
507 * comment in this file). But we know this is a NOR-specific piece of
508 * code, so we can do this. But yes, this is error-prone and we should
509 * (pre-)allocate VID header buffer instead.
511 struct ubi_vid_hdr vid_hdr
;
514 * If VID or EC is valid, we have to corrupt them before erasing.
515 * It is important to first invalidate the EC header, and then the VID
516 * header. Otherwise a power cut may lead to valid EC header and
517 * invalid VID header, in which case UBI will treat this PEB as
518 * corrupted and will try to preserve it, and print scary warnings.
520 addr
= (loff_t
)pnum
* ubi
->peb_size
;
521 err
= ubi_io_read_ec_hdr(ubi
, pnum
, &ec_hdr
, 0);
522 if (err
!= UBI_IO_BAD_HDR_EBADMSG
&& err
!= UBI_IO_BAD_HDR
&&
524 err
= mtd_write(ubi
->mtd
, addr
, 4, &written
, (void *)&data
);
529 err
= ubi_io_read_vid_hdr(ubi
, pnum
, &vid_hdr
, 0);
530 if (err
!= UBI_IO_BAD_HDR_EBADMSG
&& err
!= UBI_IO_BAD_HDR
&&
532 addr
+= ubi
->vid_hdr_aloffset
;
533 err
= mtd_write(ubi
->mtd
, addr
, 4, &written
, (void *)&data
);
541 * The PEB contains a valid VID or EC header, but we cannot invalidate
542 * it. Supposedly the flash media or the driver is screwed up, so
545 ubi_err("cannot invalidate PEB %d, write returned %d", pnum
, err
);
546 ubi_dump_flash(ubi
, pnum
, 0, ubi
->peb_size
);
551 * ubi_io_sync_erase - synchronously erase a physical eraseblock.
552 * @ubi: UBI device description object
553 * @pnum: physical eraseblock number to erase
554 * @torture: if this physical eraseblock has to be tortured
556 * This function synchronously erases physical eraseblock @pnum. If @torture
557 * flag is not zero, the physical eraseblock is checked by means of writing
558 * different patterns to it and reading them back. If the torturing is enabled,
559 * the physical eraseblock is erased more than once.
561 * This function returns the number of erasures made in case of success, %-EIO
562 * if the erasure failed or the torturing test failed, and other negative error
563 * codes in case of other errors. Note, %-EIO means that the physical
566 int ubi_io_sync_erase(struct ubi_device
*ubi
, int pnum
, int torture
)
570 ubi_assert(pnum
>= 0 && pnum
< ubi
->peb_count
);
572 err
= self_check_not_bad(ubi
, pnum
);
577 ubi_err("read-only mode");
581 if (ubi
->nor_flash
) {
582 err
= nor_erase_prepare(ubi
, pnum
);
588 ret
= torture_peb(ubi
, pnum
);
593 err
= do_sync_erase(ubi
, pnum
);
601 * ubi_io_is_bad - check if a physical eraseblock is bad.
602 * @ubi: UBI device description object
603 * @pnum: the physical eraseblock number to check
605 * This function returns a positive number if the physical eraseblock is bad,
606 * zero if not, and a negative error code if an error occurred.
608 int ubi_io_is_bad(const struct ubi_device
*ubi
, int pnum
)
610 struct mtd_info
*mtd
= ubi
->mtd
;
612 ubi_assert(pnum
>= 0 && pnum
< ubi
->peb_count
);
614 if (ubi
->bad_allowed
) {
617 ret
= mtd_block_isbad(mtd
, (loff_t
)pnum
* ubi
->peb_size
);
619 ubi_err("error %d while checking if PEB %d is bad",
622 dbg_io("PEB %d is bad", pnum
);
630 * ubi_io_mark_bad - mark a physical eraseblock as bad.
631 * @ubi: UBI device description object
632 * @pnum: the physical eraseblock number to mark
634 * This function returns zero in case of success and a negative error code in
637 int ubi_io_mark_bad(const struct ubi_device
*ubi
, int pnum
)
640 struct mtd_info
*mtd
= ubi
->mtd
;
642 ubi_assert(pnum
>= 0 && pnum
< ubi
->peb_count
);
645 ubi_err("read-only mode");
649 if (!ubi
->bad_allowed
)
652 err
= mtd_block_markbad(mtd
, (loff_t
)pnum
* ubi
->peb_size
);
654 ubi_err("cannot mark PEB %d bad, error %d", pnum
, err
);
659 * validate_ec_hdr - validate an erase counter header.
660 * @ubi: UBI device description object
661 * @ec_hdr: the erase counter header to check
663 * This function returns zero if the erase counter header is OK, and %1 if
666 static int validate_ec_hdr(const struct ubi_device
*ubi
,
667 const struct ubi_ec_hdr
*ec_hdr
)
670 int vid_hdr_offset
, leb_start
;
672 ec
= be64_to_cpu(ec_hdr
->ec
);
673 vid_hdr_offset
= be32_to_cpu(ec_hdr
->vid_hdr_offset
);
674 leb_start
= be32_to_cpu(ec_hdr
->data_offset
);
676 if (ec_hdr
->version
!= UBI_VERSION
) {
677 ubi_err("node with incompatible UBI version found: this UBI version is %d, image version is %d",
678 UBI_VERSION
, (int)ec_hdr
->version
);
682 if (vid_hdr_offset
!= ubi
->vid_hdr_offset
) {
683 ubi_err("bad VID header offset %d, expected %d",
684 vid_hdr_offset
, ubi
->vid_hdr_offset
);
688 if (leb_start
!= ubi
->leb_start
) {
689 ubi_err("bad data offset %d, expected %d",
690 leb_start
, ubi
->leb_start
);
694 if (ec
< 0 || ec
> UBI_MAX_ERASECOUNTER
) {
695 ubi_err("bad erase counter %lld", ec
);
702 ubi_err("bad EC header");
703 ubi_dump_ec_hdr(ec_hdr
);
709 * ubi_io_read_ec_hdr - read and check an erase counter header.
710 * @ubi: UBI device description object
711 * @pnum: physical eraseblock to read from
712 * @ec_hdr: a &struct ubi_ec_hdr object where to store the read erase counter
714 * @verbose: be verbose if the header is corrupted or was not found
716 * This function reads erase counter header from physical eraseblock @pnum and
717 * stores it in @ec_hdr. This function also checks CRC checksum of the read
718 * erase counter header. The following codes may be returned:
720 * o %0 if the CRC checksum is correct and the header was successfully read;
721 * o %UBI_IO_BITFLIPS if the CRC is correct, but bit-flips were detected
722 * and corrected by the flash driver; this is harmless but may indicate that
723 * this eraseblock may become bad soon (but may be not);
724 * o %UBI_IO_BAD_HDR if the erase counter header is corrupted (a CRC error);
725 * o %UBI_IO_BAD_HDR_EBADMSG is the same as %UBI_IO_BAD_HDR, but there also was
726 * a data integrity error (uncorrectable ECC error in case of NAND);
727 * o %UBI_IO_FF if only 0xFF bytes were read (the PEB is supposedly empty)
728 * o a negative error code in case of failure.
730 int ubi_io_read_ec_hdr(struct ubi_device
*ubi
, int pnum
,
731 struct ubi_ec_hdr
*ec_hdr
, int verbose
)
734 uint32_t crc
, magic
, hdr_crc
;
736 dbg_io("read EC header from PEB %d", pnum
);
737 ubi_assert(pnum
>= 0 && pnum
< ubi
->peb_count
);
739 read_err
= ubi_io_read(ubi
, ec_hdr
, pnum
, 0, UBI_EC_HDR_SIZE
);
741 if (read_err
!= UBI_IO_BITFLIPS
&& !mtd_is_eccerr(read_err
))
745 * We read all the data, but either a correctable bit-flip
746 * occurred, or MTD reported a data integrity error
747 * (uncorrectable ECC error in case of NAND). The former is
748 * harmless, the later may mean that the read data is
749 * corrupted. But we have a CRC check-sum and we will detect
750 * this. If the EC header is still OK, we just report this as
751 * there was a bit-flip, to force scrubbing.
755 magic
= be32_to_cpu(ec_hdr
->magic
);
756 if (magic
!= UBI_EC_HDR_MAGIC
) {
757 if (mtd_is_eccerr(read_err
))
758 return UBI_IO_BAD_HDR_EBADMSG
;
761 * The magic field is wrong. Let's check if we have read all
762 * 0xFF. If yes, this physical eraseblock is assumed to be
765 if (ubi_check_pattern(ec_hdr
, 0xFF, UBI_EC_HDR_SIZE
)) {
766 /* The physical eraseblock is supposedly empty */
768 ubi_warn("no EC header found at PEB %d, only 0xFF bytes",
770 dbg_bld("no EC header found at PEB %d, only 0xFF bytes",
775 return UBI_IO_FF_BITFLIPS
;
779 * This is not a valid erase counter header, and these are not
780 * 0xFF bytes. Report that the header is corrupted.
783 ubi_warn("bad magic number at PEB %d: %08x instead of %08x",
784 pnum
, magic
, UBI_EC_HDR_MAGIC
);
785 ubi_dump_ec_hdr(ec_hdr
);
787 dbg_bld("bad magic number at PEB %d: %08x instead of %08x",
788 pnum
, magic
, UBI_EC_HDR_MAGIC
);
789 return UBI_IO_BAD_HDR
;
792 crc
= crc32(UBI_CRC32_INIT
, ec_hdr
, UBI_EC_HDR_SIZE_CRC
);
793 hdr_crc
= be32_to_cpu(ec_hdr
->hdr_crc
);
795 if (hdr_crc
!= crc
) {
797 ubi_warn("bad EC header CRC at PEB %d, calculated %#08x, read %#08x",
799 ubi_dump_ec_hdr(ec_hdr
);
801 dbg_bld("bad EC header CRC at PEB %d, calculated %#08x, read %#08x",
805 return UBI_IO_BAD_HDR
;
807 return UBI_IO_BAD_HDR_EBADMSG
;
810 /* And of course validate what has just been read from the media */
811 err
= validate_ec_hdr(ubi
, ec_hdr
);
813 ubi_err("validation failed for PEB %d", pnum
);
818 * If there was %-EBADMSG, but the header CRC is still OK, report about
819 * a bit-flip to force scrubbing on this PEB.
821 return read_err
? UBI_IO_BITFLIPS
: 0;
825 * ubi_io_write_ec_hdr - write an erase counter header.
826 * @ubi: UBI device description object
827 * @pnum: physical eraseblock to write to
828 * @ec_hdr: the erase counter header to write
830 * This function writes erase counter header described by @ec_hdr to physical
831 * eraseblock @pnum. It also fills most fields of @ec_hdr before writing, so
832 * the caller do not have to fill them. Callers must only fill the @ec_hdr->ec
835 * This function returns zero in case of success and a negative error code in
836 * case of failure. If %-EIO is returned, the physical eraseblock most probably
839 int ubi_io_write_ec_hdr(struct ubi_device
*ubi
, int pnum
,
840 struct ubi_ec_hdr
*ec_hdr
)
845 dbg_io("write EC header to PEB %d", pnum
);
846 ubi_assert(pnum
>= 0 && pnum
< ubi
->peb_count
);
848 ec_hdr
->magic
= cpu_to_be32(UBI_EC_HDR_MAGIC
);
849 ec_hdr
->version
= UBI_VERSION
;
850 ec_hdr
->vid_hdr_offset
= cpu_to_be32(ubi
->vid_hdr_offset
);
851 ec_hdr
->data_offset
= cpu_to_be32(ubi
->leb_start
);
852 ec_hdr
->image_seq
= cpu_to_be32(ubi
->image_seq
);
853 crc
= crc32(UBI_CRC32_INIT
, ec_hdr
, UBI_EC_HDR_SIZE_CRC
);
854 ec_hdr
->hdr_crc
= cpu_to_be32(crc
);
856 err
= self_check_ec_hdr(ubi
, pnum
, ec_hdr
);
860 err
= ubi_io_write(ubi
, ec_hdr
, pnum
, 0, ubi
->ec_hdr_alsize
);
865 * validate_vid_hdr - validate a volume identifier header.
866 * @ubi: UBI device description object
867 * @vid_hdr: the volume identifier header to check
869 * This function checks that data stored in the volume identifier header
870 * @vid_hdr. Returns zero if the VID header is OK and %1 if not.
872 static int validate_vid_hdr(const struct ubi_device
*ubi
,
873 const struct ubi_vid_hdr
*vid_hdr
)
875 int vol_type
= vid_hdr
->vol_type
;
876 int copy_flag
= vid_hdr
->copy_flag
;
877 int vol_id
= be32_to_cpu(vid_hdr
->vol_id
);
878 int lnum
= be32_to_cpu(vid_hdr
->lnum
);
879 int compat
= vid_hdr
->compat
;
880 int data_size
= be32_to_cpu(vid_hdr
->data_size
);
881 int used_ebs
= be32_to_cpu(vid_hdr
->used_ebs
);
882 int data_pad
= be32_to_cpu(vid_hdr
->data_pad
);
883 int data_crc
= be32_to_cpu(vid_hdr
->data_crc
);
884 int usable_leb_size
= ubi
->leb_size
- data_pad
;
886 if (copy_flag
!= 0 && copy_flag
!= 1) {
887 ubi_err("bad copy_flag");
891 if (vol_id
< 0 || lnum
< 0 || data_size
< 0 || used_ebs
< 0 ||
893 ubi_err("negative values");
897 if (vol_id
>= UBI_MAX_VOLUMES
&& vol_id
< UBI_INTERNAL_VOL_START
) {
898 ubi_err("bad vol_id");
902 if (vol_id
< UBI_INTERNAL_VOL_START
&& compat
!= 0) {
903 ubi_err("bad compat");
907 if (vol_id
>= UBI_INTERNAL_VOL_START
&& compat
!= UBI_COMPAT_DELETE
&&
908 compat
!= UBI_COMPAT_RO
&& compat
!= UBI_COMPAT_PRESERVE
&&
909 compat
!= UBI_COMPAT_REJECT
) {
910 ubi_err("bad compat");
914 if (vol_type
!= UBI_VID_DYNAMIC
&& vol_type
!= UBI_VID_STATIC
) {
915 ubi_err("bad vol_type");
919 if (data_pad
>= ubi
->leb_size
/ 2) {
920 ubi_err("bad data_pad");
924 if (vol_type
== UBI_VID_STATIC
) {
926 * Although from high-level point of view static volumes may
927 * contain zero bytes of data, but no VID headers can contain
928 * zero at these fields, because they empty volumes do not have
929 * mapped logical eraseblocks.
932 ubi_err("zero used_ebs");
935 if (data_size
== 0) {
936 ubi_err("zero data_size");
939 if (lnum
< used_ebs
- 1) {
940 if (data_size
!= usable_leb_size
) {
941 ubi_err("bad data_size");
944 } else if (lnum
== used_ebs
- 1) {
945 if (data_size
== 0) {
946 ubi_err("bad data_size at last LEB");
950 ubi_err("too high lnum");
954 if (copy_flag
== 0) {
956 ubi_err("non-zero data CRC");
959 if (data_size
!= 0) {
960 ubi_err("non-zero data_size");
964 if (data_size
== 0) {
965 ubi_err("zero data_size of copy");
970 ubi_err("bad used_ebs");
978 ubi_err("bad VID header");
979 ubi_dump_vid_hdr(vid_hdr
);
985 * ubi_io_read_vid_hdr - read and check a volume identifier header.
986 * @ubi: UBI device description object
987 * @pnum: physical eraseblock number to read from
988 * @vid_hdr: &struct ubi_vid_hdr object where to store the read volume
990 * @verbose: be verbose if the header is corrupted or wasn't found
992 * This function reads the volume identifier header from physical eraseblock
993 * @pnum and stores it in @vid_hdr. It also checks CRC checksum of the read
994 * volume identifier header. The error codes are the same as in
995 * 'ubi_io_read_ec_hdr()'.
997 * Note, the implementation of this function is also very similar to
998 * 'ubi_io_read_ec_hdr()', so refer commentaries in 'ubi_io_read_ec_hdr()'.
1000 int ubi_io_read_vid_hdr(struct ubi_device
*ubi
, int pnum
,
1001 struct ubi_vid_hdr
*vid_hdr
, int verbose
)
1004 uint32_t crc
, magic
, hdr_crc
;
1007 dbg_io("read VID header from PEB %d", pnum
);
1008 ubi_assert(pnum
>= 0 && pnum
< ubi
->peb_count
);
1010 p
= (char *)vid_hdr
- ubi
->vid_hdr_shift
;
1011 read_err
= ubi_io_read(ubi
, p
, pnum
, ubi
->vid_hdr_aloffset
,
1012 ubi
->vid_hdr_alsize
);
1013 if (read_err
&& read_err
!= UBI_IO_BITFLIPS
&& !mtd_is_eccerr(read_err
))
1016 magic
= be32_to_cpu(vid_hdr
->magic
);
1017 if (magic
!= UBI_VID_HDR_MAGIC
) {
1018 if (mtd_is_eccerr(read_err
))
1019 return UBI_IO_BAD_HDR_EBADMSG
;
1021 if (ubi_check_pattern(vid_hdr
, 0xFF, UBI_VID_HDR_SIZE
)) {
1023 ubi_warn("no VID header found at PEB %d, only 0xFF bytes",
1025 dbg_bld("no VID header found at PEB %d, only 0xFF bytes",
1030 return UBI_IO_FF_BITFLIPS
;
1034 ubi_warn("bad magic number at PEB %d: %08x instead of %08x",
1035 pnum
, magic
, UBI_VID_HDR_MAGIC
);
1036 ubi_dump_vid_hdr(vid_hdr
);
1038 dbg_bld("bad magic number at PEB %d: %08x instead of %08x",
1039 pnum
, magic
, UBI_VID_HDR_MAGIC
);
1040 return UBI_IO_BAD_HDR
;
1043 crc
= crc32(UBI_CRC32_INIT
, vid_hdr
, UBI_VID_HDR_SIZE_CRC
);
1044 hdr_crc
= be32_to_cpu(vid_hdr
->hdr_crc
);
1046 if (hdr_crc
!= crc
) {
1048 ubi_warn("bad CRC at PEB %d, calculated %#08x, read %#08x",
1049 pnum
, crc
, hdr_crc
);
1050 ubi_dump_vid_hdr(vid_hdr
);
1052 dbg_bld("bad CRC at PEB %d, calculated %#08x, read %#08x",
1053 pnum
, crc
, hdr_crc
);
1055 return UBI_IO_BAD_HDR
;
1057 return UBI_IO_BAD_HDR_EBADMSG
;
1060 err
= validate_vid_hdr(ubi
, vid_hdr
);
1062 ubi_err("validation failed for PEB %d", pnum
);
1066 return read_err
? UBI_IO_BITFLIPS
: 0;
1070 * ubi_io_write_vid_hdr - write a volume identifier header.
1071 * @ubi: UBI device description object
1072 * @pnum: the physical eraseblock number to write to
1073 * @vid_hdr: the volume identifier header to write
1075 * This function writes the volume identifier header described by @vid_hdr to
1076 * physical eraseblock @pnum. This function automatically fills the
1077 * @vid_hdr->magic and the @vid_hdr->version fields, as well as calculates
1078 * header CRC checksum and stores it at vid_hdr->hdr_crc.
1080 * This function returns zero in case of success and a negative error code in
1081 * case of failure. If %-EIO is returned, the physical eraseblock probably went
1084 int ubi_io_write_vid_hdr(struct ubi_device
*ubi
, int pnum
,
1085 struct ubi_vid_hdr
*vid_hdr
)
1091 dbg_io("write VID header to PEB %d", pnum
);
1092 ubi_assert(pnum
>= 0 && pnum
< ubi
->peb_count
);
1094 err
= self_check_peb_ec_hdr(ubi
, pnum
);
1098 vid_hdr
->magic
= cpu_to_be32(UBI_VID_HDR_MAGIC
);
1099 vid_hdr
->version
= UBI_VERSION
;
1100 crc
= crc32(UBI_CRC32_INIT
, vid_hdr
, UBI_VID_HDR_SIZE_CRC
);
1101 vid_hdr
->hdr_crc
= cpu_to_be32(crc
);
1103 err
= self_check_vid_hdr(ubi
, pnum
, vid_hdr
);
1107 p
= (char *)vid_hdr
- ubi
->vid_hdr_shift
;
1108 err
= ubi_io_write(ubi
, p
, pnum
, ubi
->vid_hdr_aloffset
,
1109 ubi
->vid_hdr_alsize
);
1114 * self_check_not_bad - ensure that a physical eraseblock is not bad.
1115 * @ubi: UBI device description object
1116 * @pnum: physical eraseblock number to check
1118 * This function returns zero if the physical eraseblock is good, %-EINVAL if
1119 * it is bad and a negative error code if an error occurred.
1121 static int self_check_not_bad(const struct ubi_device
*ubi
, int pnum
)
1125 if (!ubi_dbg_chk_io(ubi
))
1128 err
= ubi_io_is_bad(ubi
, pnum
);
1132 ubi_err("self-check failed for PEB %d", pnum
);
1134 return err
> 0 ? -EINVAL
: err
;
1138 * self_check_ec_hdr - check if an erase counter header is all right.
1139 * @ubi: UBI device description object
1140 * @pnum: physical eraseblock number the erase counter header belongs to
1141 * @ec_hdr: the erase counter header to check
1143 * This function returns zero if the erase counter header contains valid
1144 * values, and %-EINVAL if not.
1146 static int self_check_ec_hdr(const struct ubi_device
*ubi
, int pnum
,
1147 const struct ubi_ec_hdr
*ec_hdr
)
1152 if (!ubi_dbg_chk_io(ubi
))
1155 magic
= be32_to_cpu(ec_hdr
->magic
);
1156 if (magic
!= UBI_EC_HDR_MAGIC
) {
1157 ubi_err("bad magic %#08x, must be %#08x",
1158 magic
, UBI_EC_HDR_MAGIC
);
1162 err
= validate_ec_hdr(ubi
, ec_hdr
);
1164 ubi_err("self-check failed for PEB %d", pnum
);
1171 ubi_dump_ec_hdr(ec_hdr
);
1177 * self_check_peb_ec_hdr - check erase counter header.
1178 * @ubi: UBI device description object
1179 * @pnum: the physical eraseblock number to check
1181 * This function returns zero if the erase counter header is all right and and
1182 * a negative error code if not or if an error occurred.
1184 static int self_check_peb_ec_hdr(const struct ubi_device
*ubi
, int pnum
)
1187 uint32_t crc
, hdr_crc
;
1188 struct ubi_ec_hdr
*ec_hdr
;
1190 if (!ubi_dbg_chk_io(ubi
))
1193 ec_hdr
= kzalloc(ubi
->ec_hdr_alsize
, GFP_NOFS
);
1197 err
= ubi_io_read(ubi
, ec_hdr
, pnum
, 0, UBI_EC_HDR_SIZE
);
1198 if (err
&& err
!= UBI_IO_BITFLIPS
&& !mtd_is_eccerr(err
))
1201 crc
= crc32(UBI_CRC32_INIT
, ec_hdr
, UBI_EC_HDR_SIZE_CRC
);
1202 hdr_crc
= be32_to_cpu(ec_hdr
->hdr_crc
);
1203 if (hdr_crc
!= crc
) {
1204 ubi_err("bad CRC, calculated %#08x, read %#08x", crc
, hdr_crc
);
1205 ubi_err("self-check failed for PEB %d", pnum
);
1206 ubi_dump_ec_hdr(ec_hdr
);
1212 err
= self_check_ec_hdr(ubi
, pnum
, ec_hdr
);
1220 * self_check_vid_hdr - check that a volume identifier header is all right.
1221 * @ubi: UBI device description object
1222 * @pnum: physical eraseblock number the volume identifier header belongs to
1223 * @vid_hdr: the volume identifier header to check
1225 * This function returns zero if the volume identifier header is all right, and
1228 static int self_check_vid_hdr(const struct ubi_device
*ubi
, int pnum
,
1229 const struct ubi_vid_hdr
*vid_hdr
)
1234 if (!ubi_dbg_chk_io(ubi
))
1237 magic
= be32_to_cpu(vid_hdr
->magic
);
1238 if (magic
!= UBI_VID_HDR_MAGIC
) {
1239 ubi_err("bad VID header magic %#08x at PEB %d, must be %#08x",
1240 magic
, pnum
, UBI_VID_HDR_MAGIC
);
1244 err
= validate_vid_hdr(ubi
, vid_hdr
);
1246 ubi_err("self-check failed for PEB %d", pnum
);
1253 ubi_err("self-check failed for PEB %d", pnum
);
1254 ubi_dump_vid_hdr(vid_hdr
);
1261 * self_check_peb_vid_hdr - check volume identifier header.
1262 * @ubi: UBI device description object
1263 * @pnum: the physical eraseblock number to check
1265 * This function returns zero if the volume identifier header is all right,
1266 * and a negative error code if not or if an error occurred.
1268 static int self_check_peb_vid_hdr(const struct ubi_device
*ubi
, int pnum
)
1271 uint32_t crc
, hdr_crc
;
1272 struct ubi_vid_hdr
*vid_hdr
;
1275 if (!ubi_dbg_chk_io(ubi
))
1278 vid_hdr
= ubi_zalloc_vid_hdr(ubi
, GFP_NOFS
);
1282 p
= (char *)vid_hdr
- ubi
->vid_hdr_shift
;
1283 err
= ubi_io_read(ubi
, p
, pnum
, ubi
->vid_hdr_aloffset
,
1284 ubi
->vid_hdr_alsize
);
1285 if (err
&& err
!= UBI_IO_BITFLIPS
&& !mtd_is_eccerr(err
))
1288 crc
= crc32(UBI_CRC32_INIT
, vid_hdr
, UBI_EC_HDR_SIZE_CRC
);
1289 hdr_crc
= be32_to_cpu(vid_hdr
->hdr_crc
);
1290 if (hdr_crc
!= crc
) {
1291 ubi_err("bad VID header CRC at PEB %d, calculated %#08x, read %#08x",
1292 pnum
, crc
, hdr_crc
);
1293 ubi_err("self-check failed for PEB %d", pnum
);
1294 ubi_dump_vid_hdr(vid_hdr
);
1300 err
= self_check_vid_hdr(ubi
, pnum
, vid_hdr
);
1303 ubi_free_vid_hdr(ubi
, vid_hdr
);
1308 * self_check_write - make sure write succeeded.
1309 * @ubi: UBI device description object
1310 * @buf: buffer with data which were written
1311 * @pnum: physical eraseblock number the data were written to
1312 * @offset: offset within the physical eraseblock the data were written to
1313 * @len: how many bytes were written
1315 * This functions reads data which were recently written and compares it with
1316 * the original data buffer - the data have to match. Returns zero if the data
1317 * match and a negative error code if not or in case of failure.
1319 static int self_check_write(struct ubi_device
*ubi
, const void *buf
, int pnum
,
1320 int offset
, int len
)
1325 loff_t addr
= (loff_t
)pnum
* ubi
->peb_size
+ offset
;
1327 if (!ubi_dbg_chk_io(ubi
))
1330 buf1
= __vmalloc(len
, GFP_NOFS
, PAGE_KERNEL
);
1332 ubi_err("cannot allocate memory to check writes");
1336 err
= mtd_read(ubi
->mtd
, addr
, len
, &read
, buf1
);
1337 if (err
&& !mtd_is_bitflip(err
))
1340 for (i
= 0; i
< len
; i
++) {
1341 uint8_t c
= ((uint8_t *)buf
)[i
];
1342 uint8_t c1
= ((uint8_t *)buf1
)[i
];
1348 ubi_err("self-check failed for PEB %d:%d, len %d",
1350 ubi_msg("data differ at position %d", i
);
1351 dump_len
= max_t(int, 128, len
- i
);
1352 ubi_msg("hex dump of the original buffer from %d to %d",
1354 print_hex_dump(KERN_DEBUG
, "", DUMP_PREFIX_OFFSET
, 32, 1,
1355 buf
+ i
, dump_len
, 1);
1356 ubi_msg("hex dump of the read buffer from %d to %d",
1358 print_hex_dump(KERN_DEBUG
, "", DUMP_PREFIX_OFFSET
, 32, 1,
1359 buf1
+ i
, dump_len
, 1);
1374 * ubi_self_check_all_ff - check that a region of flash is empty.
1375 * @ubi: UBI device description object
1376 * @pnum: the physical eraseblock number to check
1377 * @offset: the starting offset within the physical eraseblock to check
1378 * @len: the length of the region to check
1380 * This function returns zero if only 0xFF bytes are present at offset
1381 * @offset of the physical eraseblock @pnum, and a negative error code if not
1382 * or if an error occurred.
1384 int ubi_self_check_all_ff(struct ubi_device
*ubi
, int pnum
, int offset
, int len
)
1389 loff_t addr
= (loff_t
)pnum
* ubi
->peb_size
+ offset
;
1391 if (!ubi_dbg_chk_io(ubi
))
1394 buf
= __vmalloc(len
, GFP_NOFS
, PAGE_KERNEL
);
1396 ubi_err("cannot allocate memory to check for 0xFFs");
1400 err
= mtd_read(ubi
->mtd
, addr
, len
, &read
, buf
);
1401 if (err
&& !mtd_is_bitflip(err
)) {
1402 ubi_err("error %d while reading %d bytes from PEB %d:%d, read %zd bytes",
1403 err
, len
, pnum
, offset
, read
);
1407 err
= ubi_check_pattern(buf
, 0xFF, len
);
1409 ubi_err("flash region at PEB %d:%d, length %d does not contain all 0xFF bytes",
1418 ubi_err("self-check failed for PEB %d", pnum
);
1419 ubi_msg("hex dump of the %d-%d region", offset
, offset
+ len
);
1420 print_hex_dump(KERN_DEBUG
, "", DUMP_PREFIX_OFFSET
, 32, 1, buf
, len
, 1);