]>
git.ipfire.org Git - people/ms/u-boot.git/blob - drivers/mtd/ubi/io.c
2 * Copyright (c) International Business Machines Corp., 2006
3 * Copyright (c) Nokia Corporation, 2006, 2007
5 * SPDX-License-Identifier: GPL-2.0+
7 * Author: Artem Bityutskiy (Битюцкий Артём)
11 * UBI input/output unit.
13 * This unit provides a uniform way to work with all kinds of the underlying
14 * MTD devices. It also implements handy functions for reading and writing UBI
17 * We are trying to have a paranoid mindset and not to trust to what we read
18 * from the flash media in order to be more secure and robust. So this unit
19 * validates every single header it reads from the flash media.
21 * Some words about how the eraseblock headers are stored.
23 * The erase counter header is always stored at offset zero. By default, the
24 * VID header is stored after the EC header at the closest aligned offset
25 * (i.e. aligned to the minimum I/O unit size). Data starts next to the VID
26 * header at the closest aligned offset. But this default layout may be
27 * changed. For example, for different reasons (e.g., optimization) UBI may be
28 * asked to put the VID header at further offset, and even at an unaligned
29 * offset. Of course, if the offset of the VID header is unaligned, UBI adds
30 * proper padding in front of it. Data offset may also be changed but it has to
33 * About minimal I/O units. In general, UBI assumes flash device model where
34 * there is only one minimal I/O unit size. E.g., in case of NOR flash it is 1,
35 * in case of NAND flash it is a NAND page, etc. This is reported by MTD in the
36 * @ubi->mtd->writesize field. But as an exception, UBI admits of using another
37 * (smaller) minimal I/O unit size for EC and VID headers to make it possible
38 * to do different optimizations.
40 * This is extremely useful in case of NAND flashes which admit of several
41 * write operations to one NAND page. In this case UBI can fit EC and VID
42 * headers at one NAND page. Thus, UBI may use "sub-page" size as the minimal
43 * I/O unit for the headers (the @ubi->hdrs_min_io_size field). But it still
44 * reports NAND page size (@ubi->min_io_size) as a minimal I/O unit for the UBI
47 * Example: some Samsung NANDs with 2KiB pages allow 4x 512-byte writes, so
48 * although the minimal I/O unit is 2K, UBI uses 512 bytes for EC and VID
51 * Q: why not just to treat sub-page as a minimal I/O unit of this flash
52 * device, e.g., make @ubi->min_io_size = 512 in the example above?
54 * A: because when writing a sub-page, MTD still writes a full 2K page but the
55 * bytes which are no relevant to the sub-page are 0xFF. So, basically, writing
56 * 4x512 sub-pages is 4 times slower then writing one 2KiB NAND page. Thus, we
57 * prefer to use sub-pages only for EV and VID headers.
59 * As it was noted above, the VID header may start at a non-aligned offset.
60 * For example, in case of a 2KiB page NAND flash with a 512 bytes sub-page,
61 * the VID header may reside at offset 1984 which is the last 64 bytes of the
62 * last sub-page (EC header is always at offset zero). This causes some
63 * difficulties when reading and writing VID headers.
65 * Suppose we have a 64-byte buffer and we read a VID header at it. We change
66 * the data and want to write this VID header out. As we can only write in
67 * 512-byte chunks, we have to allocate one more buffer and copy our VID header
68 * to offset 448 of this buffer.
70 * The I/O unit does the following trick in order to avoid this extra copy.
71 * It always allocates a @ubi->vid_hdr_alsize bytes buffer for the VID header
72 * and returns a pointer to offset @ubi->vid_hdr_shift of this buffer. When the
73 * VID header is being written out, it shifts the VID header pointer back and
74 * writes the whole sub-page.
78 #include <linux/crc32.h>
79 #include <linux/err.h>
82 #include <ubi_uboot.h>
85 #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
86 static int paranoid_check_not_bad(const struct ubi_device
*ubi
, int pnum
);
87 static int paranoid_check_peb_ec_hdr(const struct ubi_device
*ubi
, int pnum
);
88 static int paranoid_check_ec_hdr(const struct ubi_device
*ubi
, int pnum
,
89 const struct ubi_ec_hdr
*ec_hdr
);
90 static int paranoid_check_peb_vid_hdr(const struct ubi_device
*ubi
, int pnum
);
91 static int paranoid_check_vid_hdr(const struct ubi_device
*ubi
, int pnum
,
92 const struct ubi_vid_hdr
*vid_hdr
);
93 static int paranoid_check_all_ff(struct ubi_device
*ubi
, int pnum
, int offset
,
96 #define paranoid_check_not_bad(ubi, pnum) 0
97 #define paranoid_check_peb_ec_hdr(ubi, pnum) 0
98 #define paranoid_check_ec_hdr(ubi, pnum, ec_hdr) 0
99 #define paranoid_check_peb_vid_hdr(ubi, pnum) 0
100 #define paranoid_check_vid_hdr(ubi, pnum, vid_hdr) 0
101 #define paranoid_check_all_ff(ubi, pnum, offset, len) 0
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
= paranoid_check_not_bad(ubi
, pnum
);
141 return err
> 0 ? -EINVAL
: err
;
143 addr
= (loff_t
)pnum
* ubi
->peb_size
+ offset
;
145 err
= mtd_read(ubi
->mtd
, addr
, len
, &read
, buf
);
147 if (err
== -EUCLEAN
) {
149 * -EUCLEAN is reported if there was a bit-flip which
150 * was corrected, so this is harmless.
152 ubi_msg("fixable bit-flip detected at PEB %d", pnum
);
153 ubi_assert(len
== read
);
154 return UBI_IO_BITFLIPS
;
157 if (read
!= len
&& retries
++ < UBI_IO_RETRIES
) {
158 dbg_io("error %d while reading %d bytes from PEB %d:%d, "
159 "read only %zd bytes, retry",
160 err
, len
, pnum
, offset
, read
);
165 ubi_err("error %d while reading %d bytes from PEB %d:%d, "
166 "read %zd bytes", err
, len
, pnum
, offset
, read
);
167 ubi_dbg_dump_stack();
170 * The driver should never return -EBADMSG if it failed to read
171 * all the requested data. But some buggy drivers might do
172 * this, so we change it to -EIO.
174 if (read
!= len
&& err
== -EBADMSG
) {
176 printk("%s[%d] not here\n", __func__
, __LINE__
);
180 ubi_assert(len
== read
);
182 if (ubi_dbg_is_bitflip()) {
183 dbg_msg("bit-flip (emulated)");
184 err
= UBI_IO_BITFLIPS
;
192 * ubi_io_write - write data to a physical eraseblock.
193 * @ubi: UBI device description object
194 * @buf: buffer with the data to write
195 * @pnum: physical eraseblock number to write to
196 * @offset: offset within the physical eraseblock where to write
197 * @len: how many bytes to write
199 * This function writes @len bytes of data from buffer @buf to offset @offset
200 * of physical eraseblock @pnum. If all the data were successfully written,
201 * zero is returned. If an error occurred, this function returns a negative
202 * error code. If %-EIO is returned, the physical eraseblock most probably went
205 * Note, in case of an error, it is possible that something was still written
206 * to the flash media, but may be some garbage.
208 int ubi_io_write(struct ubi_device
*ubi
, const void *buf
, int pnum
, int offset
,
215 dbg_io("write %d bytes to PEB %d:%d", len
, pnum
, offset
);
217 ubi_assert(pnum
>= 0 && pnum
< ubi
->peb_count
);
218 ubi_assert(offset
>= 0 && offset
+ len
<= ubi
->peb_size
);
219 ubi_assert(offset
% ubi
->hdrs_min_io_size
== 0);
220 ubi_assert(len
> 0 && len
% ubi
->hdrs_min_io_size
== 0);
223 ubi_err("read-only mode");
227 /* The below has to be compiled out if paranoid checks are disabled */
229 err
= paranoid_check_not_bad(ubi
, pnum
);
231 return err
> 0 ? -EINVAL
: err
;
233 /* The area we are writing to has to contain all 0xFF bytes */
234 err
= paranoid_check_all_ff(ubi
, pnum
, offset
, len
);
236 return err
> 0 ? -EINVAL
: err
;
238 if (offset
>= ubi
->leb_start
) {
240 * We write to the data area of the physical eraseblock. Make
241 * sure it has valid EC and VID headers.
243 err
= paranoid_check_peb_ec_hdr(ubi
, pnum
);
245 return err
> 0 ? -EINVAL
: err
;
246 err
= paranoid_check_peb_vid_hdr(ubi
, pnum
);
248 return err
> 0 ? -EINVAL
: err
;
251 if (ubi_dbg_is_write_failure()) {
252 dbg_err("cannot write %d bytes to PEB %d:%d "
253 "(emulated)", len
, pnum
, offset
);
254 ubi_dbg_dump_stack();
258 addr
= (loff_t
)pnum
* ubi
->peb_size
+ offset
;
259 err
= mtd_write(ubi
->mtd
, addr
, len
, &written
, buf
);
261 ubi_err("error %d while writing %d bytes to PEB %d:%d, written"
262 " %zd bytes", err
, len
, pnum
, offset
, written
);
263 ubi_dbg_dump_stack();
265 ubi_assert(written
== len
);
271 * erase_callback - MTD erasure call-back.
272 * @ei: MTD erase information object.
274 * Note, even though MTD erase interface is asynchronous, all the current
275 * implementations are synchronous anyway.
277 static void erase_callback(struct erase_info
*ei
)
279 wake_up_interruptible((wait_queue_head_t
*)ei
->priv
);
283 * do_sync_erase - synchronously erase a physical eraseblock.
284 * @ubi: UBI device description object
285 * @pnum: the physical eraseblock number to erase
287 * This function synchronously erases physical eraseblock @pnum and returns
288 * zero in case of success and a negative error code in case of failure. If
289 * %-EIO is returned, the physical eraseblock most probably went bad.
291 static int do_sync_erase(struct ubi_device
*ubi
, int pnum
)
293 int err
, retries
= 0;
294 struct erase_info ei
;
295 wait_queue_head_t wq
;
297 dbg_io("erase PEB %d", pnum
);
300 init_waitqueue_head(&wq
);
301 memset(&ei
, 0, sizeof(struct erase_info
));
304 ei
.addr
= (loff_t
)pnum
* ubi
->peb_size
;
305 ei
.len
= ubi
->peb_size
;
306 ei
.callback
= erase_callback
;
307 ei
.priv
= (unsigned long)&wq
;
309 err
= mtd_erase(ubi
->mtd
, &ei
);
311 if (retries
++ < UBI_IO_RETRIES
) {
312 dbg_io("error %d while erasing PEB %d, retry",
317 ubi_err("cannot erase PEB %d, error %d", pnum
, err
);
318 ubi_dbg_dump_stack();
322 err
= wait_event_interruptible(wq
, ei
.state
== MTD_ERASE_DONE
||
323 ei
.state
== MTD_ERASE_FAILED
);
325 ubi_err("interrupted PEB %d erasure", pnum
);
329 if (ei
.state
== MTD_ERASE_FAILED
) {
330 if (retries
++ < UBI_IO_RETRIES
) {
331 dbg_io("error while erasing PEB %d, retry", pnum
);
335 ubi_err("cannot erase PEB %d", pnum
);
336 ubi_dbg_dump_stack();
340 err
= paranoid_check_all_ff(ubi
, pnum
, 0, ubi
->peb_size
);
342 return err
> 0 ? -EINVAL
: err
;
344 if (ubi_dbg_is_erase_failure() && !err
) {
345 dbg_err("cannot erase PEB %d (emulated)", pnum
);
353 * check_pattern - check if buffer contains only a certain byte pattern.
354 * @buf: buffer to check
355 * @patt: the pattern to check
356 * @size: buffer size in bytes
358 * This function returns %1 in there are only @patt bytes in @buf, and %0 if
359 * something else was also found.
361 static int check_pattern(const void *buf
, uint8_t patt
, int size
)
365 for (i
= 0; i
< size
; i
++)
366 if (((const uint8_t *)buf
)[i
] != patt
)
371 /* Patterns to write to a physical eraseblock when torturing it */
372 static uint8_t patterns
[] = {0xa5, 0x5a, 0x0};
375 * torture_peb - test a supposedly bad physical eraseblock.
376 * @ubi: UBI device description object
377 * @pnum: the physical eraseblock number to test
379 * This function returns %-EIO if the physical eraseblock did not pass the
380 * test, a positive number of erase operations done if the test was
381 * successfully passed, and other negative error codes in case of other errors.
383 static int torture_peb(struct ubi_device
*ubi
, int pnum
)
385 int err
, i
, patt_count
;
387 patt_count
= ARRAY_SIZE(patterns
);
388 ubi_assert(patt_count
> 0);
390 mutex_lock(&ubi
->buf_mutex
);
391 for (i
= 0; i
< patt_count
; i
++) {
392 err
= do_sync_erase(ubi
, pnum
);
396 /* Make sure the PEB contains only 0xFF bytes */
397 err
= ubi_io_read(ubi
, ubi
->peb_buf1
, pnum
, 0, ubi
->peb_size
);
401 err
= check_pattern(ubi
->peb_buf1
, 0xFF, ubi
->peb_size
);
403 ubi_err("erased PEB %d, but a non-0xFF byte found",
409 /* Write a pattern and check it */
410 memset(ubi
->peb_buf1
, patterns
[i
], ubi
->peb_size
);
411 err
= ubi_io_write(ubi
, ubi
->peb_buf1
, pnum
, 0, ubi
->peb_size
);
415 memset(ubi
->peb_buf1
, ~patterns
[i
], ubi
->peb_size
);
416 err
= ubi_io_read(ubi
, ubi
->peb_buf1
, pnum
, 0, ubi
->peb_size
);
420 err
= check_pattern(ubi
->peb_buf1
, patterns
[i
], ubi
->peb_size
);
422 ubi_err("pattern %x checking failed for PEB %d",
432 mutex_unlock(&ubi
->buf_mutex
);
433 if (err
== UBI_IO_BITFLIPS
|| err
== -EBADMSG
) {
435 * If a bit-flip or data integrity error was detected, the test
436 * has not passed because it happened on a freshly erased
437 * physical eraseblock which means something is wrong with it.
439 ubi_err("read problems on freshly erased PEB %d, must be bad",
447 * ubi_io_sync_erase - synchronously erase a physical eraseblock.
448 * @ubi: UBI device description object
449 * @pnum: physical eraseblock number to erase
450 * @torture: if this physical eraseblock has to be tortured
452 * This function synchronously erases physical eraseblock @pnum. If @torture
453 * flag is not zero, the physical eraseblock is checked by means of writing
454 * different patterns to it and reading them back. If the torturing is enabled,
455 * the physical eraseblock is erased more then once.
457 * This function returns the number of erasures made in case of success, %-EIO
458 * if the erasure failed or the torturing test failed, and other negative error
459 * codes in case of other errors. Note, %-EIO means that the physical
462 int ubi_io_sync_erase(struct ubi_device
*ubi
, int pnum
, int torture
)
466 ubi_assert(pnum
>= 0 && pnum
< ubi
->peb_count
);
468 err
= paranoid_check_not_bad(ubi
, pnum
);
470 return err
> 0 ? -EINVAL
: err
;
473 ubi_err("read-only mode");
478 ret
= torture_peb(ubi
, pnum
);
483 err
= do_sync_erase(ubi
, pnum
);
491 * ubi_io_is_bad - check if a physical eraseblock is bad.
492 * @ubi: UBI device description object
493 * @pnum: the physical eraseblock number to check
495 * This function returns a positive number if the physical eraseblock is bad,
496 * zero if not, and a negative error code if an error occurred.
498 int ubi_io_is_bad(const struct ubi_device
*ubi
, int pnum
)
500 struct mtd_info
*mtd
= ubi
->mtd
;
502 ubi_assert(pnum
>= 0 && pnum
< ubi
->peb_count
);
504 if (ubi
->bad_allowed
) {
507 ret
= mtd_block_isbad(mtd
, (loff_t
)pnum
* ubi
->peb_size
);
509 ubi_err("error %d while checking if PEB %d is bad",
512 dbg_io("PEB %d is bad", pnum
);
520 * ubi_io_mark_bad - mark a physical eraseblock as bad.
521 * @ubi: UBI device description object
522 * @pnum: the physical eraseblock number to mark
524 * This function returns zero in case of success and a negative error code in
527 int ubi_io_mark_bad(const struct ubi_device
*ubi
, int pnum
)
530 struct mtd_info
*mtd
= ubi
->mtd
;
532 ubi_assert(pnum
>= 0 && pnum
< ubi
->peb_count
);
535 ubi_err("read-only mode");
539 if (!ubi
->bad_allowed
)
542 err
= mtd_block_markbad(mtd
, (loff_t
)pnum
* ubi
->peb_size
);
544 ubi_err("cannot mark PEB %d bad, error %d", pnum
, err
);
549 * validate_ec_hdr - validate an erase counter header.
550 * @ubi: UBI device description object
551 * @ec_hdr: the erase counter header to check
553 * This function returns zero if the erase counter header is OK, and %1 if
556 static int validate_ec_hdr(const struct ubi_device
*ubi
,
557 const struct ubi_ec_hdr
*ec_hdr
)
560 int vid_hdr_offset
, leb_start
;
562 ec
= be64_to_cpu(ec_hdr
->ec
);
563 vid_hdr_offset
= be32_to_cpu(ec_hdr
->vid_hdr_offset
);
564 leb_start
= be32_to_cpu(ec_hdr
->data_offset
);
566 if (ec_hdr
->version
!= UBI_VERSION
) {
567 ubi_err("node with incompatible UBI version found: "
568 "this UBI version is %d, image version is %d",
569 UBI_VERSION
, (int)ec_hdr
->version
);
573 if (vid_hdr_offset
!= ubi
->vid_hdr_offset
) {
574 ubi_err("bad VID header offset %d, expected %d",
575 vid_hdr_offset
, ubi
->vid_hdr_offset
);
579 if (leb_start
!= ubi
->leb_start
) {
580 ubi_err("bad data offset %d, expected %d",
581 leb_start
, ubi
->leb_start
);
585 if (ec
< 0 || ec
> UBI_MAX_ERASECOUNTER
) {
586 ubi_err("bad erase counter %lld", ec
);
593 ubi_err("bad EC header");
594 ubi_dbg_dump_ec_hdr(ec_hdr
);
595 ubi_dbg_dump_stack();
600 * ubi_io_read_ec_hdr - read and check an erase counter header.
601 * @ubi: UBI device description object
602 * @pnum: physical eraseblock to read from
603 * @ec_hdr: a &struct ubi_ec_hdr object where to store the read erase counter
605 * @verbose: be verbose if the header is corrupted or was not found
607 * This function reads erase counter header from physical eraseblock @pnum and
608 * stores it in @ec_hdr. This function also checks CRC checksum of the read
609 * erase counter header. The following codes may be returned:
611 * o %0 if the CRC checksum is correct and the header was successfully read;
612 * o %UBI_IO_BITFLIPS if the CRC is correct, but bit-flips were detected
613 * and corrected by the flash driver; this is harmless but may indicate that
614 * this eraseblock may become bad soon (but may be not);
615 * o %UBI_IO_BAD_EC_HDR if the erase counter header is corrupted (a CRC error);
616 * o %UBI_IO_PEB_EMPTY if the physical eraseblock is empty;
617 * o a negative error code in case of failure.
619 int ubi_io_read_ec_hdr(struct ubi_device
*ubi
, int pnum
,
620 struct ubi_ec_hdr
*ec_hdr
, int verbose
)
622 int err
, read_err
= 0;
623 uint32_t crc
, magic
, hdr_crc
;
625 dbg_io("read EC header from PEB %d", pnum
);
626 ubi_assert(pnum
>= 0 && pnum
< ubi
->peb_count
);
630 err
= ubi_io_read(ubi
, ec_hdr
, pnum
, 0, UBI_EC_HDR_SIZE
);
632 if (err
!= UBI_IO_BITFLIPS
&& err
!= -EBADMSG
)
636 * We read all the data, but either a correctable bit-flip
637 * occurred, or MTD reported about some data integrity error,
638 * like an ECC error in case of NAND. The former is harmless,
639 * the later may mean that the read data is corrupted. But we
640 * have a CRC check-sum and we will detect this. If the EC
641 * header is still OK, we just report this as there was a
647 magic
= be32_to_cpu(ec_hdr
->magic
);
648 if (magic
!= UBI_EC_HDR_MAGIC
) {
650 * The magic field is wrong. Let's check if we have read all
651 * 0xFF. If yes, this physical eraseblock is assumed to be
654 * But if there was a read error, we do not test it for all
655 * 0xFFs. Even if it does contain all 0xFFs, this error
656 * indicates that something is still wrong with this physical
657 * eraseblock and we anyway cannot treat it as empty.
659 if (read_err
!= -EBADMSG
&&
660 check_pattern(ec_hdr
, 0xFF, UBI_EC_HDR_SIZE
)) {
661 /* The physical eraseblock is supposedly empty */
664 * The below is just a paranoid check, it has to be
665 * compiled out if paranoid checks are disabled.
667 err
= paranoid_check_all_ff(ubi
, pnum
, 0,
670 return err
> 0 ? UBI_IO_BAD_EC_HDR
: err
;
673 ubi_warn("no EC header found at PEB %d, "
674 "only 0xFF bytes", pnum
);
675 return UBI_IO_PEB_EMPTY
;
679 * This is not a valid erase counter header, and these are not
680 * 0xFF bytes. Report that the header is corrupted.
683 ubi_warn("bad magic number at PEB %d: %08x instead of "
684 "%08x", pnum
, magic
, UBI_EC_HDR_MAGIC
);
685 ubi_dbg_dump_ec_hdr(ec_hdr
);
687 return UBI_IO_BAD_EC_HDR
;
690 crc
= crc32(UBI_CRC32_INIT
, ec_hdr
, UBI_EC_HDR_SIZE_CRC
);
691 hdr_crc
= be32_to_cpu(ec_hdr
->hdr_crc
);
693 if (hdr_crc
!= crc
) {
695 ubi_warn("bad EC header CRC at PEB %d, calculated %#08x,"
696 " read %#08x", pnum
, crc
, hdr_crc
);
697 ubi_dbg_dump_ec_hdr(ec_hdr
);
699 return UBI_IO_BAD_EC_HDR
;
702 /* And of course validate what has just been read from the media */
703 err
= validate_ec_hdr(ubi
, ec_hdr
);
705 ubi_err("validation failed for PEB %d", pnum
);
709 return read_err
? UBI_IO_BITFLIPS
: 0;
713 * ubi_io_write_ec_hdr - write an erase counter header.
714 * @ubi: UBI device description object
715 * @pnum: physical eraseblock to write to
716 * @ec_hdr: the erase counter header to write
718 * This function writes erase counter header described by @ec_hdr to physical
719 * eraseblock @pnum. It also fills most fields of @ec_hdr before writing, so
720 * the caller do not have to fill them. Callers must only fill the @ec_hdr->ec
723 * This function returns zero in case of success and a negative error code in
724 * case of failure. If %-EIO is returned, the physical eraseblock most probably
727 int ubi_io_write_ec_hdr(struct ubi_device
*ubi
, int pnum
,
728 struct ubi_ec_hdr
*ec_hdr
)
733 dbg_io("write EC header to PEB %d", pnum
);
734 ubi_assert(pnum
>= 0 && pnum
< ubi
->peb_count
);
736 ec_hdr
->magic
= cpu_to_be32(UBI_EC_HDR_MAGIC
);
737 ec_hdr
->version
= UBI_VERSION
;
738 ec_hdr
->vid_hdr_offset
= cpu_to_be32(ubi
->vid_hdr_offset
);
739 ec_hdr
->data_offset
= cpu_to_be32(ubi
->leb_start
);
740 crc
= crc32(UBI_CRC32_INIT
, ec_hdr
, UBI_EC_HDR_SIZE_CRC
);
741 ec_hdr
->hdr_crc
= cpu_to_be32(crc
);
743 err
= paranoid_check_ec_hdr(ubi
, pnum
, ec_hdr
);
747 err
= ubi_io_write(ubi
, ec_hdr
, pnum
, 0, ubi
->ec_hdr_alsize
);
752 * validate_vid_hdr - validate a volume identifier header.
753 * @ubi: UBI device description object
754 * @vid_hdr: the volume identifier header to check
756 * This function checks that data stored in the volume identifier header
757 * @vid_hdr. Returns zero if the VID header is OK and %1 if not.
759 static int validate_vid_hdr(const struct ubi_device
*ubi
,
760 const struct ubi_vid_hdr
*vid_hdr
)
762 int vol_type
= vid_hdr
->vol_type
;
763 int copy_flag
= vid_hdr
->copy_flag
;
764 int vol_id
= be32_to_cpu(vid_hdr
->vol_id
);
765 int lnum
= be32_to_cpu(vid_hdr
->lnum
);
766 int compat
= vid_hdr
->compat
;
767 int data_size
= be32_to_cpu(vid_hdr
->data_size
);
768 int used_ebs
= be32_to_cpu(vid_hdr
->used_ebs
);
769 int data_pad
= be32_to_cpu(vid_hdr
->data_pad
);
770 int data_crc
= be32_to_cpu(vid_hdr
->data_crc
);
771 int usable_leb_size
= ubi
->leb_size
- data_pad
;
773 if (copy_flag
!= 0 && copy_flag
!= 1) {
774 dbg_err("bad copy_flag");
778 if (vol_id
< 0 || lnum
< 0 || data_size
< 0 || used_ebs
< 0 ||
780 dbg_err("negative values");
784 if (vol_id
>= UBI_MAX_VOLUMES
&& vol_id
< UBI_INTERNAL_VOL_START
) {
785 dbg_err("bad vol_id");
789 if (vol_id
< UBI_INTERNAL_VOL_START
&& compat
!= 0) {
790 dbg_err("bad compat");
794 if (vol_id
>= UBI_INTERNAL_VOL_START
&& compat
!= UBI_COMPAT_DELETE
&&
795 compat
!= UBI_COMPAT_RO
&& compat
!= UBI_COMPAT_PRESERVE
&&
796 compat
!= UBI_COMPAT_REJECT
) {
797 dbg_err("bad compat");
801 if (vol_type
!= UBI_VID_DYNAMIC
&& vol_type
!= UBI_VID_STATIC
) {
802 dbg_err("bad vol_type");
806 if (data_pad
>= ubi
->leb_size
/ 2) {
807 dbg_err("bad data_pad");
811 if (vol_type
== UBI_VID_STATIC
) {
813 * Although from high-level point of view static volumes may
814 * contain zero bytes of data, but no VID headers can contain
815 * zero at these fields, because they empty volumes do not have
816 * mapped logical eraseblocks.
819 dbg_err("zero used_ebs");
822 if (data_size
== 0) {
823 dbg_err("zero data_size");
826 if (lnum
< used_ebs
- 1) {
827 if (data_size
!= usable_leb_size
) {
828 dbg_err("bad data_size");
831 } else if (lnum
== used_ebs
- 1) {
832 if (data_size
== 0) {
833 dbg_err("bad data_size at last LEB");
837 dbg_err("too high lnum");
841 if (copy_flag
== 0) {
843 dbg_err("non-zero data CRC");
846 if (data_size
!= 0) {
847 dbg_err("non-zero data_size");
851 if (data_size
== 0) {
852 dbg_err("zero data_size of copy");
857 dbg_err("bad used_ebs");
865 ubi_err("bad VID header");
866 ubi_dbg_dump_vid_hdr(vid_hdr
);
867 ubi_dbg_dump_stack();
872 * ubi_io_read_vid_hdr - read and check a volume identifier header.
873 * @ubi: UBI device description object
874 * @pnum: physical eraseblock number to read from
875 * @vid_hdr: &struct ubi_vid_hdr object where to store the read volume
877 * @verbose: be verbose if the header is corrupted or wasn't found
879 * This function reads the volume identifier header from physical eraseblock
880 * @pnum and stores it in @vid_hdr. It also checks CRC checksum of the read
881 * volume identifier header. The following codes may be returned:
883 * o %0 if the CRC checksum is correct and the header was successfully read;
884 * o %UBI_IO_BITFLIPS if the CRC is correct, but bit-flips were detected
885 * and corrected by the flash driver; this is harmless but may indicate that
886 * this eraseblock may become bad soon;
887 * o %UBI_IO_BAD_VID_HRD if the volume identifier header is corrupted (a CRC
889 * o %UBI_IO_PEB_FREE if the physical eraseblock is free (i.e., there is no VID
891 * o a negative error code in case of failure.
893 int ubi_io_read_vid_hdr(struct ubi_device
*ubi
, int pnum
,
894 struct ubi_vid_hdr
*vid_hdr
, int verbose
)
896 int err
, read_err
= 0;
897 uint32_t crc
, magic
, hdr_crc
;
900 dbg_io("read VID header from PEB %d", pnum
);
901 ubi_assert(pnum
>= 0 && pnum
< ubi
->peb_count
);
905 p
= (char *)vid_hdr
- ubi
->vid_hdr_shift
;
906 err
= ubi_io_read(ubi
, p
, pnum
, ubi
->vid_hdr_aloffset
,
907 ubi
->vid_hdr_alsize
);
909 if (err
!= UBI_IO_BITFLIPS
&& err
!= -EBADMSG
)
913 * We read all the data, but either a correctable bit-flip
914 * occurred, or MTD reported about some data integrity error,
915 * like an ECC error in case of NAND. The former is harmless,
916 * the later may mean the read data is corrupted. But we have a
917 * CRC check-sum and we will identify this. If the VID header is
918 * still OK, we just report this as there was a bit-flip.
923 magic
= be32_to_cpu(vid_hdr
->magic
);
924 if (magic
!= UBI_VID_HDR_MAGIC
) {
926 * If we have read all 0xFF bytes, the VID header probably does
927 * not exist and the physical eraseblock is assumed to be free.
929 * But if there was a read error, we do not test the data for
930 * 0xFFs. Even if it does contain all 0xFFs, this error
931 * indicates that something is still wrong with this physical
932 * eraseblock and it cannot be regarded as free.
934 if (read_err
!= -EBADMSG
&&
935 check_pattern(vid_hdr
, 0xFF, UBI_VID_HDR_SIZE
)) {
936 /* The physical eraseblock is supposedly free */
939 * The below is just a paranoid check, it has to be
940 * compiled out if paranoid checks are disabled.
942 err
= paranoid_check_all_ff(ubi
, pnum
, ubi
->leb_start
,
945 return err
> 0 ? UBI_IO_BAD_VID_HDR
: err
;
948 ubi_warn("no VID header found at PEB %d, "
949 "only 0xFF bytes", pnum
);
950 return UBI_IO_PEB_FREE
;
954 * This is not a valid VID header, and these are not 0xFF
955 * bytes. Report that the header is corrupted.
958 ubi_warn("bad magic number at PEB %d: %08x instead of "
959 "%08x", pnum
, magic
, UBI_VID_HDR_MAGIC
);
960 ubi_dbg_dump_vid_hdr(vid_hdr
);
962 return UBI_IO_BAD_VID_HDR
;
965 crc
= crc32(UBI_CRC32_INIT
, vid_hdr
, UBI_VID_HDR_SIZE_CRC
);
966 hdr_crc
= be32_to_cpu(vid_hdr
->hdr_crc
);
968 if (hdr_crc
!= crc
) {
970 ubi_warn("bad CRC at PEB %d, calculated %#08x, "
971 "read %#08x", pnum
, crc
, hdr_crc
);
972 ubi_dbg_dump_vid_hdr(vid_hdr
);
974 return UBI_IO_BAD_VID_HDR
;
977 /* Validate the VID header that we have just read */
978 err
= validate_vid_hdr(ubi
, vid_hdr
);
980 ubi_err("validation failed for PEB %d", pnum
);
984 return read_err
? UBI_IO_BITFLIPS
: 0;
988 * ubi_io_write_vid_hdr - write a volume identifier header.
989 * @ubi: UBI device description object
990 * @pnum: the physical eraseblock number to write to
991 * @vid_hdr: the volume identifier header to write
993 * This function writes the volume identifier header described by @vid_hdr to
994 * physical eraseblock @pnum. This function automatically fills the
995 * @vid_hdr->magic and the @vid_hdr->version fields, as well as calculates
996 * header CRC checksum and stores it at vid_hdr->hdr_crc.
998 * This function returns zero in case of success and a negative error code in
999 * case of failure. If %-EIO is returned, the physical eraseblock probably went
1002 int ubi_io_write_vid_hdr(struct ubi_device
*ubi
, int pnum
,
1003 struct ubi_vid_hdr
*vid_hdr
)
1009 dbg_io("write VID header to PEB %d", pnum
);
1010 ubi_assert(pnum
>= 0 && pnum
< ubi
->peb_count
);
1012 err
= paranoid_check_peb_ec_hdr(ubi
, pnum
);
1014 return err
> 0 ? -EINVAL
: err
;
1016 vid_hdr
->magic
= cpu_to_be32(UBI_VID_HDR_MAGIC
);
1017 vid_hdr
->version
= UBI_VERSION
;
1018 crc
= crc32(UBI_CRC32_INIT
, vid_hdr
, UBI_VID_HDR_SIZE_CRC
);
1019 vid_hdr
->hdr_crc
= cpu_to_be32(crc
);
1021 err
= paranoid_check_vid_hdr(ubi
, pnum
, vid_hdr
);
1025 p
= (char *)vid_hdr
- ubi
->vid_hdr_shift
;
1026 err
= ubi_io_write(ubi
, p
, pnum
, ubi
->vid_hdr_aloffset
,
1027 ubi
->vid_hdr_alsize
);
1031 #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
1034 * paranoid_check_not_bad - ensure that a physical eraseblock is not bad.
1035 * @ubi: UBI device description object
1036 * @pnum: physical eraseblock number to check
1038 * This function returns zero if the physical eraseblock is good, a positive
1039 * number if it is bad and a negative error code if an error occurred.
1041 static int paranoid_check_not_bad(const struct ubi_device
*ubi
, int pnum
)
1045 err
= ubi_io_is_bad(ubi
, pnum
);
1049 ubi_err("paranoid check failed for PEB %d", pnum
);
1050 ubi_dbg_dump_stack();
1055 * paranoid_check_ec_hdr - check if an erase counter header is all right.
1056 * @ubi: UBI device description object
1057 * @pnum: physical eraseblock number the erase counter header belongs to
1058 * @ec_hdr: the erase counter header to check
1060 * This function returns zero if the erase counter header contains valid
1061 * values, and %1 if not.
1063 static int paranoid_check_ec_hdr(const struct ubi_device
*ubi
, int pnum
,
1064 const struct ubi_ec_hdr
*ec_hdr
)
1069 magic
= be32_to_cpu(ec_hdr
->magic
);
1070 if (magic
!= UBI_EC_HDR_MAGIC
) {
1071 ubi_err("bad magic %#08x, must be %#08x",
1072 magic
, UBI_EC_HDR_MAGIC
);
1076 err
= validate_ec_hdr(ubi
, ec_hdr
);
1078 ubi_err("paranoid check failed for PEB %d", pnum
);
1085 ubi_dbg_dump_ec_hdr(ec_hdr
);
1086 ubi_dbg_dump_stack();
1091 * paranoid_check_peb_ec_hdr - check that the erase counter header of a
1092 * physical eraseblock is in-place and is all right.
1093 * @ubi: UBI device description object
1094 * @pnum: the physical eraseblock number to check
1096 * This function returns zero if the erase counter header is all right, %1 if
1097 * not, and a negative error code if an error occurred.
1099 static int paranoid_check_peb_ec_hdr(const struct ubi_device
*ubi
, int pnum
)
1102 uint32_t crc
, hdr_crc
;
1103 struct ubi_ec_hdr
*ec_hdr
;
1105 ec_hdr
= kzalloc(ubi
->ec_hdr_alsize
, GFP_NOFS
);
1109 err
= ubi_io_read(ubi
, ec_hdr
, pnum
, 0, UBI_EC_HDR_SIZE
);
1110 if (err
&& err
!= UBI_IO_BITFLIPS
&& err
!= -EBADMSG
)
1113 crc
= crc32(UBI_CRC32_INIT
, ec_hdr
, UBI_EC_HDR_SIZE_CRC
);
1114 hdr_crc
= be32_to_cpu(ec_hdr
->hdr_crc
);
1115 if (hdr_crc
!= crc
) {
1116 ubi_err("bad CRC, calculated %#08x, read %#08x", crc
, hdr_crc
);
1117 ubi_err("paranoid check failed for PEB %d", pnum
);
1118 ubi_dbg_dump_ec_hdr(ec_hdr
);
1119 ubi_dbg_dump_stack();
1124 err
= paranoid_check_ec_hdr(ubi
, pnum
, ec_hdr
);
1132 * paranoid_check_vid_hdr - check that a volume identifier header is all right.
1133 * @ubi: UBI device description object
1134 * @pnum: physical eraseblock number the volume identifier header belongs to
1135 * @vid_hdr: the volume identifier header to check
1137 * This function returns zero if the volume identifier header is all right, and
1140 static int paranoid_check_vid_hdr(const struct ubi_device
*ubi
, int pnum
,
1141 const struct ubi_vid_hdr
*vid_hdr
)
1146 magic
= be32_to_cpu(vid_hdr
->magic
);
1147 if (magic
!= UBI_VID_HDR_MAGIC
) {
1148 ubi_err("bad VID header magic %#08x at PEB %d, must be %#08x",
1149 magic
, pnum
, UBI_VID_HDR_MAGIC
);
1153 err
= validate_vid_hdr(ubi
, vid_hdr
);
1155 ubi_err("paranoid check failed for PEB %d", pnum
);
1162 ubi_err("paranoid check failed for PEB %d", pnum
);
1163 ubi_dbg_dump_vid_hdr(vid_hdr
);
1164 ubi_dbg_dump_stack();
1170 * paranoid_check_peb_vid_hdr - check that the volume identifier header of a
1171 * physical eraseblock is in-place and is all right.
1172 * @ubi: UBI device description object
1173 * @pnum: the physical eraseblock number to check
1175 * This function returns zero if the volume identifier header is all right,
1176 * %1 if not, and a negative error code if an error occurred.
1178 static int paranoid_check_peb_vid_hdr(const struct ubi_device
*ubi
, int pnum
)
1181 uint32_t crc
, hdr_crc
;
1182 struct ubi_vid_hdr
*vid_hdr
;
1185 vid_hdr
= ubi_zalloc_vid_hdr(ubi
, GFP_NOFS
);
1189 p
= (char *)vid_hdr
- ubi
->vid_hdr_shift
;
1190 err
= ubi_io_read(ubi
, p
, pnum
, ubi
->vid_hdr_aloffset
,
1191 ubi
->vid_hdr_alsize
);
1192 if (err
&& err
!= UBI_IO_BITFLIPS
&& err
!= -EBADMSG
)
1195 crc
= crc32(UBI_CRC32_INIT
, vid_hdr
, UBI_EC_HDR_SIZE_CRC
);
1196 hdr_crc
= be32_to_cpu(vid_hdr
->hdr_crc
);
1197 if (hdr_crc
!= crc
) {
1198 ubi_err("bad VID header CRC at PEB %d, calculated %#08x, "
1199 "read %#08x", pnum
, crc
, hdr_crc
);
1200 ubi_err("paranoid check failed for PEB %d", pnum
);
1201 ubi_dbg_dump_vid_hdr(vid_hdr
);
1202 ubi_dbg_dump_stack();
1207 err
= paranoid_check_vid_hdr(ubi
, pnum
, vid_hdr
);
1210 ubi_free_vid_hdr(ubi
, vid_hdr
);
1215 * paranoid_check_all_ff - check that a region of flash is empty.
1216 * @ubi: UBI device description object
1217 * @pnum: the physical eraseblock number to check
1218 * @offset: the starting offset within the physical eraseblock to check
1219 * @len: the length of the region to check
1221 * This function returns zero if only 0xFF bytes are present at offset
1222 * @offset of the physical eraseblock @pnum, %1 if not, and a negative error
1223 * code if an error occurred.
1225 static int paranoid_check_all_ff(struct ubi_device
*ubi
, int pnum
, int offset
,
1230 loff_t addr
= (loff_t
)pnum
* ubi
->peb_size
+ offset
;
1232 mutex_lock(&ubi
->dbg_buf_mutex
);
1233 err
= mtd_read(ubi
->mtd
, addr
, len
, &read
, ubi
->dbg_peb_buf
);
1234 if (err
&& err
!= -EUCLEAN
) {
1235 ubi_err("error %d while reading %d bytes from PEB %d:%d, "
1236 "read %zd bytes", err
, len
, pnum
, offset
, read
);
1240 err
= check_pattern(ubi
->dbg_peb_buf
, 0xFF, len
);
1242 ubi_err("flash region at PEB %d:%d, length %d does not "
1243 "contain all 0xFF bytes", pnum
, offset
, len
);
1246 mutex_unlock(&ubi
->dbg_buf_mutex
);
1251 ubi_err("paranoid check failed for PEB %d", pnum
);
1252 dbg_msg("hex dump of the %d-%d region", offset
, offset
+ len
);
1253 print_hex_dump(KERN_DEBUG
, "", DUMP_PREFIX_OFFSET
, 32, 1,
1254 ubi
->dbg_peb_buf
, len
, 1);
1257 ubi_dbg_dump_stack();
1258 mutex_unlock(&ubi
->dbg_buf_mutex
);
1262 #endif /* CONFIG_MTD_UBI_DEBUG_PARANOID */