blob: c2960ac9f39c9e863216c91b607e157c0ff65271 [file] [log] [blame]
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001/*
2 * Copyright (c) International Business Machines Corp., 2006
3 * Copyright (c) Nokia Corporation, 2006, 2007
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
13 * the GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 *
19 * Author: Artem Bityutskiy (Битюцкий Артём)
20 */
21
22/*
Artem Bityutskiy85c6e6e2008-07-16 10:25:56 +030023 * UBI input/output sub-system.
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +040024 *
Artem Bityutskiy85c6e6e2008-07-16 10:25:56 +030025 * 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.
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +040028 *
29 * We are trying to have a paranoid mindset and not to trust to what we read
Artem Bityutskiy85c6e6e2008-07-16 10:25:56 +030030 * 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.
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +040032 *
33 * Some words about how the eraseblock headers are stored.
34 *
35 * The erase counter header is always stored at offset zero. By default, the
36 * VID header is stored after the EC header at the closest aligned offset
37 * (i.e. aligned to the minimum I/O unit size). Data starts next to the VID
38 * header at the closest aligned offset. But this default layout may be
39 * changed. For example, for different reasons (e.g., optimization) UBI may be
40 * asked to put the VID header at further offset, and even at an unaligned
41 * offset. Of course, if the offset of the VID header is unaligned, UBI adds
42 * proper padding in front of it. Data offset may also be changed but it has to
43 * be aligned.
44 *
45 * About minimal I/O units. In general, UBI assumes flash device model where
46 * there is only one minimal I/O unit size. E.g., in case of NOR flash it is 1,
47 * in case of NAND flash it is a NAND page, etc. This is reported by MTD in the
48 * @ubi->mtd->writesize field. But as an exception, UBI admits of using another
49 * (smaller) minimal I/O unit size for EC and VID headers to make it possible
50 * to do different optimizations.
51 *
52 * This is extremely useful in case of NAND flashes which admit of several
53 * write operations to one NAND page. In this case UBI can fit EC and VID
54 * headers at one NAND page. Thus, UBI may use "sub-page" size as the minimal
55 * I/O unit for the headers (the @ubi->hdrs_min_io_size field). But it still
56 * reports NAND page size (@ubi->min_io_size) as a minimal I/O unit for the UBI
57 * users.
58 *
59 * Example: some Samsung NANDs with 2KiB pages allow 4x 512-byte writes, so
60 * although the minimal I/O unit is 2K, UBI uses 512 bytes for EC and VID
61 * headers.
62 *
63 * Q: why not just to treat sub-page as a minimal I/O unit of this flash
64 * device, e.g., make @ubi->min_io_size = 512 in the example above?
65 *
66 * A: because when writing a sub-page, MTD still writes a full 2K page but the
Shinya Kuribayashibe436f62010-05-06 19:22:09 +090067 * 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.
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +040070 *
71 * As it was noted above, the VID header may start at a non-aligned offset.
72 * For example, in case of a 2KiB page NAND flash with a 512 bytes sub-page,
73 * the VID header may reside at offset 1984 which is the last 64 bytes of the
74 * last sub-page (EC header is always at offset zero). This causes some
75 * difficulties when reading and writing VID headers.
76 *
77 * Suppose we have a 64-byte buffer and we read a VID header at it. We change
78 * the data and want to write this VID header out. As we can only write in
79 * 512-byte chunks, we have to allocate one more buffer and copy our VID header
80 * to offset 448 of this buffer.
81 *
Artem Bityutskiy85c6e6e2008-07-16 10:25:56 +030082 * 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.
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +040087 */
88
89#include <linux/crc32.h>
90#include <linux/err.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090091#include <linux/slab.h>
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +040092#include "ubi.h"
93
94#ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
95static int paranoid_check_not_bad(const struct ubi_device *ubi, int pnum);
96static int paranoid_check_peb_ec_hdr(const struct ubi_device *ubi, int pnum);
97static int paranoid_check_ec_hdr(const struct ubi_device *ubi, int pnum,
98 const struct ubi_ec_hdr *ec_hdr);
99static int paranoid_check_peb_vid_hdr(const struct ubi_device *ubi, int pnum);
100static int paranoid_check_vid_hdr(const struct ubi_device *ubi, int pnum,
101 const struct ubi_vid_hdr *vid_hdr);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400102#else
103#define paranoid_check_not_bad(ubi, pnum) 0
104#define paranoid_check_peb_ec_hdr(ubi, pnum) 0
105#define paranoid_check_ec_hdr(ubi, pnum, ec_hdr) 0
106#define paranoid_check_peb_vid_hdr(ubi, pnum) 0
107#define paranoid_check_vid_hdr(ubi, pnum, vid_hdr) 0
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400108#endif
109
110/**
111 * ubi_io_read - read data from a physical eraseblock.
112 * @ubi: UBI device description object
113 * @buf: buffer where to store the read data
114 * @pnum: physical eraseblock number to read from
115 * @offset: offset within the physical eraseblock from where to read
116 * @len: how many bytes to read
117 *
118 * This function reads data from offset @offset of physical eraseblock @pnum
119 * and stores the read data in the @buf buffer. The following return codes are
120 * possible:
121 *
122 * o %0 if all the requested data were successfully read;
123 * o %UBI_IO_BITFLIPS if all the requested data were successfully read, but
124 * correctable bit-flips were detected; this is harmless but may indicate
125 * that this eraseblock may become bad soon (but do not have to);
Artem Bityutskiy63b6c1e2007-07-17 15:04:20 +0300126 * 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;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400129 * o %-EIO if some I/O error occurred;
130 * o other negative error codes in case of other errors.
131 */
132int ubi_io_read(const struct ubi_device *ubi, void *buf, int pnum, int offset,
133 int len)
134{
135 int err, retries = 0;
136 size_t read;
137 loff_t addr;
138
139 dbg_io("read %d bytes from PEB %d:%d", len, pnum, offset);
140
141 ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
142 ubi_assert(offset >= 0 && offset + len <= ubi->peb_size);
143 ubi_assert(len > 0);
144
145 err = paranoid_check_not_bad(ubi, pnum);
146 if (err)
Artem Bityutskiyadbf05e2010-01-20 10:28:58 +0200147 return err;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400148
149 addr = (loff_t)pnum * ubi->peb_size + offset;
150retry:
151 err = ubi->mtd->read(ubi->mtd, addr, len, &read, buf);
152 if (err) {
Artem Bityutskiyf5d5b1f2010-06-14 08:15:39 +0300153 const char *errstr = (err == -EBADMSG) ? " (ECC error)" : "";
Artem Bityutskiy1a49af22010-06-08 10:59:07 +0300154
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400155 if (err == -EUCLEAN) {
156 /*
157 * -EUCLEAN is reported if there was a bit-flip which
158 * was corrected, so this is harmless.
Artem Bityutskiy8c1e6ee2008-07-18 12:20:23 +0300159 *
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.
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400163 */
Artem Bityutskiy8c1e6ee2008-07-18 12:20:23 +0300164 dbg_msg("fixable bit-flip detected at PEB %d", pnum);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400165 ubi_assert(len == read);
166 return UBI_IO_BITFLIPS;
167 }
168
169 if (read != len && retries++ < UBI_IO_RETRIES) {
Artem Bityutskiy1a49af22010-06-08 10:59:07 +0300170 dbg_io("error %d%s while reading %d bytes from PEB %d:%d,"
Artem Bityutskiy9c9ec142008-07-18 13:19:52 +0300171 " read only %zd bytes, retry",
Artem Bityutskiy1a49af22010-06-08 10:59:07 +0300172 err, errstr, len, pnum, offset, read);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400173 yield();
174 goto retry;
175 }
176
Artem Bityutskiyf5d5b1f2010-06-14 08:15:39 +0300177 ubi_err("error %d%s while reading %d bytes from PEB %d:%d, "
Artem Bityutskiy1a49af22010-06-08 10:59:07 +0300178 "read %zd bytes", err, errstr, len, pnum, offset, read);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400179 ubi_dbg_dump_stack();
Artem Bityutskiy2362a532007-10-18 20:09:41 +0300180
181 /*
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.
185 */
186 if (read != len && err == -EBADMSG) {
187 ubi_assert(0);
188 err = -EIO;
189 }
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400190 } else {
191 ubi_assert(len == read);
192
193 if (ubi_dbg_is_bitflip()) {
Artem Bityutskiyc8566352008-07-16 17:40:22 +0300194 dbg_gen("bit-flip (emulated)");
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400195 err = UBI_IO_BITFLIPS;
196 }
197 }
198
199 return err;
200}
201
202/**
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
209 *
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
214 * bad.
215 *
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.
218 */
Artem Bityutskiye88d6e102007-08-29 14:51:52 +0300219int ubi_io_write(struct ubi_device *ubi, const void *buf, int pnum, int offset,
220 int len)
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400221{
222 int err;
223 size_t written;
224 loff_t addr;
225
226 dbg_io("write %d bytes to PEB %d:%d", len, pnum, offset);
227
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);
232
233 if (ubi->ro_mode) {
234 ubi_err("read-only mode");
235 return -EROFS;
236 }
237
238 /* The below has to be compiled out if paranoid checks are disabled */
239
240 err = paranoid_check_not_bad(ubi, pnum);
241 if (err)
Artem Bityutskiyadbf05e2010-01-20 10:28:58 +0200242 return err;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400243
244 /* The area we are writing to has to contain all 0xFF bytes */
Artem Bityutskiy40a71a82009-06-28 19:16:55 +0300245 err = ubi_dbg_check_all_ff(ubi, pnum, offset, len);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400246 if (err)
Artem Bityutskiyadbf05e2010-01-20 10:28:58 +0200247 return err;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400248
249 if (offset >= ubi->leb_start) {
250 /*
251 * We write to the data area of the physical eraseblock. Make
252 * sure it has valid EC and VID headers.
253 */
254 err = paranoid_check_peb_ec_hdr(ubi, pnum);
255 if (err)
Artem Bityutskiyadbf05e2010-01-20 10:28:58 +0200256 return err;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400257 err = paranoid_check_peb_vid_hdr(ubi, pnum);
258 if (err)
Artem Bityutskiyadbf05e2010-01-20 10:28:58 +0200259 return err;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400260 }
261
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();
266 return -EIO;
267 }
268
269 addr = (loff_t)pnum * ubi->peb_size + offset;
270 err = ubi->mtd->write(ubi->mtd, addr, len, &written, buf);
271 if (err) {
Artem Bityutskiyebf53f42009-07-06 08:57:53 +0300272 ubi_err("error %d while writing %d bytes to PEB %d:%d, written "
273 "%zd bytes", err, len, pnum, offset, written);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400274 ubi_dbg_dump_stack();
Artem Bityutskiy867996b2009-07-24 15:31:33 +0300275 ubi_dbg_dump_flash(ubi, pnum, offset, len);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400276 } else
277 ubi_assert(written == len);
278
Artem Bityutskiy6e9065d2010-01-25 17:09:30 +0200279 if (!err) {
280 err = ubi_dbg_check_write(ubi, buf, pnum, offset, len);
281 if (err)
282 return err;
283
284 /*
285 * Since we always write sequentially, the rest of the PEB has
286 * to contain only 0xFF bytes.
287 */
288 offset += len;
289 len = ubi->peb_size - offset;
290 if (len)
291 err = ubi_dbg_check_all_ff(ubi, pnum, offset, len);
292 }
293
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400294 return err;
295}
296
297/**
298 * erase_callback - MTD erasure call-back.
299 * @ei: MTD erase information object.
300 *
301 * Note, even though MTD erase interface is asynchronous, all the current
302 * implementations are synchronous anyway.
303 */
304static void erase_callback(struct erase_info *ei)
305{
306 wake_up_interruptible((wait_queue_head_t *)ei->priv);
307}
308
309/**
310 * do_sync_erase - synchronously erase a physical eraseblock.
311 * @ubi: UBI device description object
312 * @pnum: the physical eraseblock number to erase
313 *
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.
317 */
Artem Bityutskiye88d6e102007-08-29 14:51:52 +0300318static int do_sync_erase(struct ubi_device *ubi, int pnum)
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400319{
320 int err, retries = 0;
321 struct erase_info ei;
322 wait_queue_head_t wq;
323
324 dbg_io("erase PEB %d", pnum);
325
326retry:
327 init_waitqueue_head(&wq);
328 memset(&ei, 0, sizeof(struct erase_info));
329
330 ei.mtd = ubi->mtd;
Brijesh Singh2f176f72007-07-05 15:07:35 +0530331 ei.addr = (loff_t)pnum * ubi->peb_size;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400332 ei.len = ubi->peb_size;
333 ei.callback = erase_callback;
334 ei.priv = (unsigned long)&wq;
335
336 err = ubi->mtd->erase(ubi->mtd, &ei);
337 if (err) {
338 if (retries++ < UBI_IO_RETRIES) {
339 dbg_io("error %d while erasing PEB %d, retry",
340 err, pnum);
341 yield();
342 goto retry;
343 }
344 ubi_err("cannot erase PEB %d, error %d", pnum, err);
345 ubi_dbg_dump_stack();
346 return err;
347 }
348
349 err = wait_event_interruptible(wq, ei.state == MTD_ERASE_DONE ||
350 ei.state == MTD_ERASE_FAILED);
351 if (err) {
352 ubi_err("interrupted PEB %d erasure", pnum);
353 return -EINTR;
354 }
355
356 if (ei.state == MTD_ERASE_FAILED) {
357 if (retries++ < UBI_IO_RETRIES) {
358 dbg_io("error while erasing PEB %d, retry", pnum);
359 yield();
360 goto retry;
361 }
362 ubi_err("cannot erase PEB %d", pnum);
363 ubi_dbg_dump_stack();
364 return -EIO;
365 }
366
Artem Bityutskiy40a71a82009-06-28 19:16:55 +0300367 err = ubi_dbg_check_all_ff(ubi, pnum, 0, ubi->peb_size);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400368 if (err)
Artem Bityutskiyadbf05e2010-01-20 10:28:58 +0200369 return err;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400370
371 if (ubi_dbg_is_erase_failure() && !err) {
372 dbg_err("cannot erase PEB %d (emulated)", pnum);
373 return -EIO;
374 }
375
376 return 0;
377}
378
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400379/* Patterns to write to a physical eraseblock when torturing it */
380static uint8_t patterns[] = {0xa5, 0x5a, 0x0};
381
382/**
383 * torture_peb - test a supposedly bad physical eraseblock.
384 * @ubi: UBI device description object
385 * @pnum: the physical eraseblock number to test
386 *
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.
390 */
Artem Bityutskiye88d6e102007-08-29 14:51:52 +0300391static int torture_peb(struct ubi_device *ubi, int pnum)
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400392{
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400393 int err, i, patt_count;
394
Artem Bityutskiy8c1e6ee2008-07-18 12:20:23 +0300395 ubi_msg("run torture test for PEB %d", pnum);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400396 patt_count = ARRAY_SIZE(patterns);
397 ubi_assert(patt_count > 0);
398
Artem Bityutskiye88d6e102007-08-29 14:51:52 +0300399 mutex_lock(&ubi->buf_mutex);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400400 for (i = 0; i < patt_count; i++) {
401 err = do_sync_erase(ubi, pnum);
402 if (err)
403 goto out;
404
405 /* Make sure the PEB contains only 0xFF bytes */
Artem Bityutskiye88d6e102007-08-29 14:51:52 +0300406 err = ubi_io_read(ubi, ubi->peb_buf1, pnum, 0, ubi->peb_size);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400407 if (err)
408 goto out;
409
Artem Bityutskiybb00e182010-07-31 09:37:34 +0300410 err = ubi_check_pattern(ubi->peb_buf1, 0xFF, ubi->peb_size);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400411 if (err == 0) {
412 ubi_err("erased PEB %d, but a non-0xFF byte found",
413 pnum);
414 err = -EIO;
415 goto out;
416 }
417
418 /* Write a pattern and check it */
Artem Bityutskiye88d6e102007-08-29 14:51:52 +0300419 memset(ubi->peb_buf1, patterns[i], ubi->peb_size);
420 err = ubi_io_write(ubi, ubi->peb_buf1, pnum, 0, ubi->peb_size);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400421 if (err)
422 goto out;
423
Artem Bityutskiye88d6e102007-08-29 14:51:52 +0300424 memset(ubi->peb_buf1, ~patterns[i], ubi->peb_size);
425 err = ubi_io_read(ubi, ubi->peb_buf1, pnum, 0, ubi->peb_size);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400426 if (err)
427 goto out;
428
Artem Bityutskiybb00e182010-07-31 09:37:34 +0300429 err = ubi_check_pattern(ubi->peb_buf1, patterns[i],
430 ubi->peb_size);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400431 if (err == 0) {
432 ubi_err("pattern %x checking failed for PEB %d",
433 patterns[i], pnum);
434 err = -EIO;
435 goto out;
436 }
437 }
438
439 err = patt_count;
Artem Bityutskiy8c1e6ee2008-07-18 12:20:23 +0300440 ubi_msg("PEB %d passed torture test, do not mark it a bad", pnum);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400441
442out:
Artem Bityutskiye88d6e102007-08-29 14:51:52 +0300443 mutex_unlock(&ubi->buf_mutex);
Artem Bityutskiy8d2d4012007-07-22 22:32:51 +0300444 if (err == UBI_IO_BITFLIPS || err == -EBADMSG) {
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400445 /*
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.
449 */
Artem Bityutskiy8d2d4012007-07-22 22:32:51 +0300450 ubi_err("read problems on freshly erased PEB %d, must be bad",
451 pnum);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400452 err = -EIO;
Artem Bityutskiy8d2d4012007-07-22 22:32:51 +0300453 }
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400454 return err;
455}
456
457/**
Artem Bityutskiyebf53f42009-07-06 08:57:53 +0300458 * nor_erase_prepare - prepare a NOR flash PEB for erasure.
459 * @ubi: UBI device description object
460 * @pnum: physical eraseblock number to prepare
461 *
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.
466 *
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).
472 *
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.
476 */
477static int nor_erase_prepare(struct ubi_device *ubi, int pnum)
478{
Artem Bityutskiyde75c772009-07-24 16:18:04 +0300479 int err, err1;
Artem Bityutskiyebf53f42009-07-06 08:57:53 +0300480 size_t written;
481 loff_t addr;
482 uint32_t data = 0;
Artem Bityutskiyde75c772009-07-24 16:18:04 +0300483 struct ubi_vid_hdr vid_hdr;
Artem Bityutskiyebf53f42009-07-06 08:57:53 +0300484
Artem Bityutskiy5b289b52009-07-19 14:09:46 +0300485 addr = (loff_t)pnum * ubi->peb_size + ubi->vid_hdr_aloffset;
Artem Bityutskiy83c20992009-07-08 10:15:41 +0300486 err = ubi->mtd->write(ubi->mtd, addr, 4, &written, (void *)&data);
Artem Bityutskiyde75c772009-07-24 16:18:04 +0300487 if (!err) {
488 addr -= ubi->vid_hdr_aloffset;
489 err = ubi->mtd->write(ubi->mtd, addr, 4, &written,
490 (void *)&data);
491 if (!err)
492 return 0;
Artem Bityutskiyebf53f42009-07-06 08:57:53 +0300493 }
494
Artem Bityutskiyde75c772009-07-24 16:18:04 +0300495 /*
496 * We failed to write to the media. This was observed with Spansion
497 * S29GL512N NOR flash. Most probably the eraseblock erasure was
498 * interrupted at a very inappropriate moment, so it became unwritable.
499 * In this case we probably anyway have garbage in this PEB.
500 */
501 err1 = ubi_io_read_vid_hdr(ubi, pnum, &vid_hdr, 0);
Artem Bityutskiy756e1df2010-09-03 01:30:16 +0300502 if (err1 == UBI_IO_BAD_HDR_EBADMSG || err1 == UBI_IO_BAD_HDR)
Artem Bityutskiyde75c772009-07-24 16:18:04 +0300503 /*
504 * The VID header is corrupted, so we can safely erase this
505 * PEB and not afraid that it will be treated as a valid PEB in
506 * case of an unclean reboot.
507 */
508 return 0;
Artem Bityutskiy5b289b52009-07-19 14:09:46 +0300509
Artem Bityutskiyde75c772009-07-24 16:18:04 +0300510 /*
511 * The PEB contains a valid VID header, but we cannot invalidate it.
512 * Supposedly the flash media or the driver is screwed up, so return an
513 * error.
514 */
515 ubi_err("cannot invalidate PEB %d, write returned %d read returned %d",
516 pnum, err, err1);
517 ubi_dbg_dump_flash(ubi, pnum, 0, ubi->peb_size);
518 return -EIO;
Artem Bityutskiyebf53f42009-07-06 08:57:53 +0300519}
520
521/**
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400522 * ubi_io_sync_erase - synchronously erase a physical eraseblock.
523 * @ubi: UBI device description object
524 * @pnum: physical eraseblock number to erase
525 * @torture: if this physical eraseblock has to be tortured
526 *
527 * This function synchronously erases physical eraseblock @pnum. If @torture
528 * flag is not zero, the physical eraseblock is checked by means of writing
529 * different patterns to it and reading them back. If the torturing is enabled,
Frederik Schwarzer025dfda2008-10-16 19:02:37 +0200530 * the physical eraseblock is erased more than once.
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400531 *
532 * This function returns the number of erasures made in case of success, %-EIO
533 * if the erasure failed or the torturing test failed, and other negative error
534 * codes in case of other errors. Note, %-EIO means that the physical
535 * eraseblock is bad.
536 */
Artem Bityutskiye88d6e102007-08-29 14:51:52 +0300537int ubi_io_sync_erase(struct ubi_device *ubi, int pnum, int torture)
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400538{
539 int err, ret = 0;
540
541 ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
542
543 err = paranoid_check_not_bad(ubi, pnum);
544 if (err != 0)
Artem Bityutskiyadbf05e2010-01-20 10:28:58 +0200545 return err;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400546
547 if (ubi->ro_mode) {
548 ubi_err("read-only mode");
549 return -EROFS;
550 }
551
Artem Bityutskiyebf53f42009-07-06 08:57:53 +0300552 if (ubi->nor_flash) {
553 err = nor_erase_prepare(ubi, pnum);
554 if (err)
555 return err;
556 }
557
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400558 if (torture) {
559 ret = torture_peb(ubi, pnum);
560 if (ret < 0)
561 return ret;
562 }
563
564 err = do_sync_erase(ubi, pnum);
565 if (err)
566 return err;
567
568 return ret + 1;
569}
570
571/**
572 * ubi_io_is_bad - check if a physical eraseblock is bad.
573 * @ubi: UBI device description object
574 * @pnum: the physical eraseblock number to check
575 *
576 * This function returns a positive number if the physical eraseblock is bad,
577 * zero if not, and a negative error code if an error occurred.
578 */
579int ubi_io_is_bad(const struct ubi_device *ubi, int pnum)
580{
581 struct mtd_info *mtd = ubi->mtd;
582
583 ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
584
585 if (ubi->bad_allowed) {
586 int ret;
587
588 ret = mtd->block_isbad(mtd, (loff_t)pnum * ubi->peb_size);
589 if (ret < 0)
590 ubi_err("error %d while checking if PEB %d is bad",
591 ret, pnum);
592 else if (ret)
593 dbg_io("PEB %d is bad", pnum);
594 return ret;
595 }
596
597 return 0;
598}
599
600/**
601 * ubi_io_mark_bad - mark a physical eraseblock as bad.
602 * @ubi: UBI device description object
603 * @pnum: the physical eraseblock number to mark
604 *
605 * This function returns zero in case of success and a negative error code in
606 * case of failure.
607 */
608int ubi_io_mark_bad(const struct ubi_device *ubi, int pnum)
609{
610 int err;
611 struct mtd_info *mtd = ubi->mtd;
612
613 ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
614
615 if (ubi->ro_mode) {
616 ubi_err("read-only mode");
617 return -EROFS;
618 }
619
620 if (!ubi->bad_allowed)
621 return 0;
622
623 err = mtd->block_markbad(mtd, (loff_t)pnum * ubi->peb_size);
624 if (err)
625 ubi_err("cannot mark PEB %d bad, error %d", pnum, err);
626 return err;
627}
628
629/**
630 * validate_ec_hdr - validate an erase counter header.
631 * @ubi: UBI device description object
632 * @ec_hdr: the erase counter header to check
633 *
634 * This function returns zero if the erase counter header is OK, and %1 if
635 * not.
636 */
Artem Bityutskiyfe96efc2009-06-30 16:11:59 +0300637static int validate_ec_hdr(const struct ubi_device *ubi,
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400638 const struct ubi_ec_hdr *ec_hdr)
639{
640 long long ec;
Artem Bityutskiyfe96efc2009-06-30 16:11:59 +0300641 int vid_hdr_offset, leb_start;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400642
Christoph Hellwig3261ebd2007-05-21 17:41:46 +0300643 ec = be64_to_cpu(ec_hdr->ec);
644 vid_hdr_offset = be32_to_cpu(ec_hdr->vid_hdr_offset);
645 leb_start = be32_to_cpu(ec_hdr->data_offset);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400646
647 if (ec_hdr->version != UBI_VERSION) {
648 ubi_err("node with incompatible UBI version found: "
649 "this UBI version is %d, image version is %d",
650 UBI_VERSION, (int)ec_hdr->version);
651 goto bad;
652 }
653
654 if (vid_hdr_offset != ubi->vid_hdr_offset) {
655 ubi_err("bad VID header offset %d, expected %d",
656 vid_hdr_offset, ubi->vid_hdr_offset);
657 goto bad;
658 }
659
660 if (leb_start != ubi->leb_start) {
661 ubi_err("bad data offset %d, expected %d",
662 leb_start, ubi->leb_start);
663 goto bad;
664 }
665
666 if (ec < 0 || ec > UBI_MAX_ERASECOUNTER) {
667 ubi_err("bad erase counter %lld", ec);
668 goto bad;
669 }
670
671 return 0;
672
673bad:
674 ubi_err("bad EC header");
675 ubi_dbg_dump_ec_hdr(ec_hdr);
676 ubi_dbg_dump_stack();
677 return 1;
678}
679
680/**
681 * ubi_io_read_ec_hdr - read and check an erase counter header.
682 * @ubi: UBI device description object
683 * @pnum: physical eraseblock to read from
684 * @ec_hdr: a &struct ubi_ec_hdr object where to store the read erase counter
685 * header
686 * @verbose: be verbose if the header is corrupted or was not found
687 *
688 * This function reads erase counter header from physical eraseblock @pnum and
689 * stores it in @ec_hdr. This function also checks CRC checksum of the read
690 * erase counter header. The following codes may be returned:
691 *
692 * o %0 if the CRC checksum is correct and the header was successfully read;
693 * o %UBI_IO_BITFLIPS if the CRC is correct, but bit-flips were detected
694 * and corrected by the flash driver; this is harmless but may indicate that
695 * this eraseblock may become bad soon (but may be not);
Artem Bityutskiy786d7832010-04-30 16:50:22 +0300696 * o %UBI_IO_BAD_HDR if the erase counter header is corrupted (a CRC error);
Artem Bityutskiy756e1df2010-09-03 01:30:16 +0300697 * o %UBI_IO_BAD_HDR_EBADMSG is the same as %UBI_IO_BAD_HDR, but there also was
698 * a data integrity error (uncorrectable ECC error in case of NAND);
Artem Bityutskiy74d82d22010-09-03 02:11:20 +0300699 * o %UBI_IO_FF if only 0xFF bytes were read (the PEB is supposedly empty)
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400700 * o a negative error code in case of failure.
701 */
Artem Bityutskiye88d6e102007-08-29 14:51:52 +0300702int ubi_io_read_ec_hdr(struct ubi_device *ubi, int pnum,
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400703 struct ubi_ec_hdr *ec_hdr, int verbose)
704{
Artem Bityutskiy92e1a7d2010-09-03 14:22:17 +0300705 int err, read_err;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400706 uint32_t crc, magic, hdr_crc;
707
708 dbg_io("read EC header from PEB %d", pnum);
709 ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
710
Artem Bityutskiy92e1a7d2010-09-03 14:22:17 +0300711 read_err = ubi_io_read(ubi, ec_hdr, pnum, 0, UBI_EC_HDR_SIZE);
712 if (read_err) {
713 if (read_err != UBI_IO_BITFLIPS && read_err != -EBADMSG)
714 return read_err;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400715
716 /*
717 * We read all the data, but either a correctable bit-flip
Artem Bityutskiy756e1df2010-09-03 01:30:16 +0300718 * occurred, or MTD reported a data integrity error
719 * (uncorrectable ECC error in case of NAND). The former is
720 * harmless, the later may mean that the read data is
721 * corrupted. But we have a CRC check-sum and we will detect
722 * this. If the EC header is still OK, we just report this as
723 * there was a bit-flip, to force scrubbing.
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400724 */
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400725 }
726
Christoph Hellwig3261ebd2007-05-21 17:41:46 +0300727 magic = be32_to_cpu(ec_hdr->magic);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400728 if (magic != UBI_EC_HDR_MAGIC) {
Artem Bityutskiy92e1a7d2010-09-03 14:22:17 +0300729 if (read_err == -EBADMSG)
730 return UBI_IO_BAD_HDR_EBADMSG;
Artem Bityutskiyeb895802010-05-03 09:04:39 +0300731
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400732 /*
733 * The magic field is wrong. Let's check if we have read all
734 * 0xFF. If yes, this physical eraseblock is assumed to be
735 * empty.
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400736 */
Artem Bityutskiybb00e182010-07-31 09:37:34 +0300737 if (ubi_check_pattern(ec_hdr, 0xFF, UBI_EC_HDR_SIZE)) {
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400738 /* The physical eraseblock is supposedly empty */
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400739 if (verbose)
740 ubi_warn("no EC header found at PEB %d, "
741 "only 0xFF bytes", pnum);
Artem Bityutskiyed458192008-11-12 10:14:10 +0200742 else if (UBI_IO_DEBUG)
743 dbg_msg("no EC header found at PEB %d, "
744 "only 0xFF bytes", pnum);
Artem Bityutskiy92e1a7d2010-09-03 14:22:17 +0300745 if (!read_err)
746 return UBI_IO_FF;
747 else
748 return UBI_IO_FF_BITFLIPS;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400749 }
750
751 /*
752 * This is not a valid erase counter header, and these are not
753 * 0xFF bytes. Report that the header is corrupted.
754 */
755 if (verbose) {
756 ubi_warn("bad magic number at PEB %d: %08x instead of "
757 "%08x", pnum, magic, UBI_EC_HDR_MAGIC);
758 ubi_dbg_dump_ec_hdr(ec_hdr);
Artem Bityutskiyed458192008-11-12 10:14:10 +0200759 } else if (UBI_IO_DEBUG)
760 dbg_msg("bad magic number at PEB %d: %08x instead of "
761 "%08x", pnum, magic, UBI_EC_HDR_MAGIC);
Artem Bityutskiy786d7832010-04-30 16:50:22 +0300762 return UBI_IO_BAD_HDR;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400763 }
764
765 crc = crc32(UBI_CRC32_INIT, ec_hdr, UBI_EC_HDR_SIZE_CRC);
Christoph Hellwig3261ebd2007-05-21 17:41:46 +0300766 hdr_crc = be32_to_cpu(ec_hdr->hdr_crc);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400767
768 if (hdr_crc != crc) {
769 if (verbose) {
Artem Bityutskiy9c9ec142008-07-18 13:19:52 +0300770 ubi_warn("bad EC header CRC at PEB %d, calculated "
771 "%#08x, read %#08x", pnum, crc, hdr_crc);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400772 ubi_dbg_dump_ec_hdr(ec_hdr);
Artem Bityutskiyed458192008-11-12 10:14:10 +0200773 } else if (UBI_IO_DEBUG)
774 dbg_msg("bad EC header CRC at PEB %d, calculated "
775 "%#08x, read %#08x", pnum, crc, hdr_crc);
Artem Bityutskiy92e1a7d2010-09-03 14:22:17 +0300776
777 if (!read_err)
778 return UBI_IO_BAD_HDR;
779 else
780 return UBI_IO_BAD_HDR_EBADMSG;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400781 }
782
783 /* And of course validate what has just been read from the media */
784 err = validate_ec_hdr(ubi, ec_hdr);
785 if (err) {
786 ubi_err("validation failed for PEB %d", pnum);
787 return -EINVAL;
788 }
789
Artem Bityutskiyeb895802010-05-03 09:04:39 +0300790 /*
791 * If there was %-EBADMSG, but the header CRC is still OK, report about
792 * a bit-flip to force scrubbing on this PEB.
793 */
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400794 return read_err ? UBI_IO_BITFLIPS : 0;
795}
796
797/**
798 * ubi_io_write_ec_hdr - write an erase counter header.
799 * @ubi: UBI device description object
800 * @pnum: physical eraseblock to write to
801 * @ec_hdr: the erase counter header to write
802 *
803 * This function writes erase counter header described by @ec_hdr to physical
804 * eraseblock @pnum. It also fills most fields of @ec_hdr before writing, so
805 * the caller do not have to fill them. Callers must only fill the @ec_hdr->ec
806 * field.
807 *
808 * This function returns zero in case of success and a negative error code in
809 * case of failure. If %-EIO is returned, the physical eraseblock most probably
810 * went bad.
811 */
Artem Bityutskiye88d6e102007-08-29 14:51:52 +0300812int ubi_io_write_ec_hdr(struct ubi_device *ubi, int pnum,
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400813 struct ubi_ec_hdr *ec_hdr)
814{
815 int err;
816 uint32_t crc;
817
818 dbg_io("write EC header to PEB %d", pnum);
819 ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
820
Christoph Hellwig3261ebd2007-05-21 17:41:46 +0300821 ec_hdr->magic = cpu_to_be32(UBI_EC_HDR_MAGIC);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400822 ec_hdr->version = UBI_VERSION;
Christoph Hellwig3261ebd2007-05-21 17:41:46 +0300823 ec_hdr->vid_hdr_offset = cpu_to_be32(ubi->vid_hdr_offset);
824 ec_hdr->data_offset = cpu_to_be32(ubi->leb_start);
Adrian Hunter0c6c7fa2009-06-26 14:58:01 +0300825 ec_hdr->image_seq = cpu_to_be32(ubi->image_seq);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400826 crc = crc32(UBI_CRC32_INIT, ec_hdr, UBI_EC_HDR_SIZE_CRC);
Christoph Hellwig3261ebd2007-05-21 17:41:46 +0300827 ec_hdr->hdr_crc = cpu_to_be32(crc);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400828
829 err = paranoid_check_ec_hdr(ubi, pnum, ec_hdr);
830 if (err)
Artem Bityutskiyadbf05e2010-01-20 10:28:58 +0200831 return err;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400832
833 err = ubi_io_write(ubi, ec_hdr, pnum, 0, ubi->ec_hdr_alsize);
834 return err;
835}
836
837/**
838 * validate_vid_hdr - validate a volume identifier header.
839 * @ubi: UBI device description object
840 * @vid_hdr: the volume identifier header to check
841 *
842 * This function checks that data stored in the volume identifier header
843 * @vid_hdr. Returns zero if the VID header is OK and %1 if not.
844 */
845static int validate_vid_hdr(const struct ubi_device *ubi,
846 const struct ubi_vid_hdr *vid_hdr)
847{
848 int vol_type = vid_hdr->vol_type;
849 int copy_flag = vid_hdr->copy_flag;
Christoph Hellwig3261ebd2007-05-21 17:41:46 +0300850 int vol_id = be32_to_cpu(vid_hdr->vol_id);
851 int lnum = be32_to_cpu(vid_hdr->lnum);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400852 int compat = vid_hdr->compat;
Christoph Hellwig3261ebd2007-05-21 17:41:46 +0300853 int data_size = be32_to_cpu(vid_hdr->data_size);
854 int used_ebs = be32_to_cpu(vid_hdr->used_ebs);
855 int data_pad = be32_to_cpu(vid_hdr->data_pad);
856 int data_crc = be32_to_cpu(vid_hdr->data_crc);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400857 int usable_leb_size = ubi->leb_size - data_pad;
858
859 if (copy_flag != 0 && copy_flag != 1) {
860 dbg_err("bad copy_flag");
861 goto bad;
862 }
863
864 if (vol_id < 0 || lnum < 0 || data_size < 0 || used_ebs < 0 ||
865 data_pad < 0) {
866 dbg_err("negative values");
867 goto bad;
868 }
869
870 if (vol_id >= UBI_MAX_VOLUMES && vol_id < UBI_INTERNAL_VOL_START) {
871 dbg_err("bad vol_id");
872 goto bad;
873 }
874
875 if (vol_id < UBI_INTERNAL_VOL_START && compat != 0) {
876 dbg_err("bad compat");
877 goto bad;
878 }
879
880 if (vol_id >= UBI_INTERNAL_VOL_START && compat != UBI_COMPAT_DELETE &&
881 compat != UBI_COMPAT_RO && compat != UBI_COMPAT_PRESERVE &&
882 compat != UBI_COMPAT_REJECT) {
883 dbg_err("bad compat");
884 goto bad;
885 }
886
887 if (vol_type != UBI_VID_DYNAMIC && vol_type != UBI_VID_STATIC) {
888 dbg_err("bad vol_type");
889 goto bad;
890 }
891
892 if (data_pad >= ubi->leb_size / 2) {
893 dbg_err("bad data_pad");
894 goto bad;
895 }
896
897 if (vol_type == UBI_VID_STATIC) {
898 /*
899 * Although from high-level point of view static volumes may
900 * contain zero bytes of data, but no VID headers can contain
901 * zero at these fields, because they empty volumes do not have
902 * mapped logical eraseblocks.
903 */
904 if (used_ebs == 0) {
905 dbg_err("zero used_ebs");
906 goto bad;
907 }
908 if (data_size == 0) {
909 dbg_err("zero data_size");
910 goto bad;
911 }
912 if (lnum < used_ebs - 1) {
913 if (data_size != usable_leb_size) {
914 dbg_err("bad data_size");
915 goto bad;
916 }
917 } else if (lnum == used_ebs - 1) {
918 if (data_size == 0) {
919 dbg_err("bad data_size at last LEB");
920 goto bad;
921 }
922 } else {
923 dbg_err("too high lnum");
924 goto bad;
925 }
926 } else {
927 if (copy_flag == 0) {
928 if (data_crc != 0) {
929 dbg_err("non-zero data CRC");
930 goto bad;
931 }
932 if (data_size != 0) {
933 dbg_err("non-zero data_size");
934 goto bad;
935 }
936 } else {
937 if (data_size == 0) {
938 dbg_err("zero data_size of copy");
939 goto bad;
940 }
941 }
942 if (used_ebs != 0) {
943 dbg_err("bad used_ebs");
944 goto bad;
945 }
946 }
947
948 return 0;
949
950bad:
951 ubi_err("bad VID header");
952 ubi_dbg_dump_vid_hdr(vid_hdr);
953 ubi_dbg_dump_stack();
954 return 1;
955}
956
957/**
958 * ubi_io_read_vid_hdr - read and check a volume identifier header.
959 * @ubi: UBI device description object
960 * @pnum: physical eraseblock number to read from
961 * @vid_hdr: &struct ubi_vid_hdr object where to store the read volume
962 * identifier header
963 * @verbose: be verbose if the header is corrupted or wasn't found
964 *
965 * This function reads the volume identifier header from physical eraseblock
966 * @pnum and stores it in @vid_hdr. It also checks CRC checksum of the read
Artem Bityutskiy74d82d22010-09-03 02:11:20 +0300967 * volume identifier header. The error codes are the same as in
968 * 'ubi_io_read_ec_hdr()'.
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400969 *
Artem Bityutskiy74d82d22010-09-03 02:11:20 +0300970 * Note, the implementation of this function is also very similar to
971 * 'ubi_io_read_ec_hdr()', so refer commentaries in 'ubi_io_read_ec_hdr()'.
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400972 */
Artem Bityutskiye88d6e102007-08-29 14:51:52 +0300973int ubi_io_read_vid_hdr(struct ubi_device *ubi, int pnum,
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400974 struct ubi_vid_hdr *vid_hdr, int verbose)
975{
Artem Bityutskiy92e1a7d2010-09-03 14:22:17 +0300976 int err, read_err;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400977 uint32_t crc, magic, hdr_crc;
978 void *p;
979
980 dbg_io("read VID header from PEB %d", pnum);
981 ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
982
983 p = (char *)vid_hdr - ubi->vid_hdr_shift;
Artem Bityutskiy92e1a7d2010-09-03 14:22:17 +0300984 read_err = ubi_io_read(ubi, p, pnum, ubi->vid_hdr_aloffset,
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400985 ubi->vid_hdr_alsize);
Artem Bityutskiy92e1a7d2010-09-03 14:22:17 +0300986 if (read_err && read_err != UBI_IO_BITFLIPS && read_err != -EBADMSG)
987 return read_err;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400988
Christoph Hellwig3261ebd2007-05-21 17:41:46 +0300989 magic = be32_to_cpu(vid_hdr->magic);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400990 if (magic != UBI_VID_HDR_MAGIC) {
Artem Bityutskiy92e1a7d2010-09-03 14:22:17 +0300991 if (read_err == -EBADMSG)
992 return UBI_IO_BAD_HDR_EBADMSG;
Artem Bityutskiyeb895802010-05-03 09:04:39 +0300993
Artem Bityutskiybb00e182010-07-31 09:37:34 +0300994 if (ubi_check_pattern(vid_hdr, 0xFF, UBI_VID_HDR_SIZE)) {
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +0400995 if (verbose)
996 ubi_warn("no VID header found at PEB %d, "
997 "only 0xFF bytes", pnum);
Artem Bityutskiyed458192008-11-12 10:14:10 +0200998 else if (UBI_IO_DEBUG)
999 dbg_msg("no VID header found at PEB %d, "
1000 "only 0xFF bytes", pnum);
Artem Bityutskiy92e1a7d2010-09-03 14:22:17 +03001001 if (!read_err)
1002 return UBI_IO_FF;
1003 else
1004 return UBI_IO_FF_BITFLIPS;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001005 }
1006
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001007 if (verbose) {
1008 ubi_warn("bad magic number at PEB %d: %08x instead of "
1009 "%08x", pnum, magic, UBI_VID_HDR_MAGIC);
1010 ubi_dbg_dump_vid_hdr(vid_hdr);
Artem Bityutskiyed458192008-11-12 10:14:10 +02001011 } else if (UBI_IO_DEBUG)
1012 dbg_msg("bad magic number at PEB %d: %08x instead of "
1013 "%08x", pnum, magic, UBI_VID_HDR_MAGIC);
Artem Bityutskiy786d7832010-04-30 16:50:22 +03001014 return UBI_IO_BAD_HDR;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001015 }
1016
1017 crc = crc32(UBI_CRC32_INIT, vid_hdr, UBI_VID_HDR_SIZE_CRC);
Christoph Hellwig3261ebd2007-05-21 17:41:46 +03001018 hdr_crc = be32_to_cpu(vid_hdr->hdr_crc);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001019
1020 if (hdr_crc != crc) {
1021 if (verbose) {
1022 ubi_warn("bad CRC at PEB %d, calculated %#08x, "
1023 "read %#08x", pnum, crc, hdr_crc);
1024 ubi_dbg_dump_vid_hdr(vid_hdr);
Artem Bityutskiyed458192008-11-12 10:14:10 +02001025 } else if (UBI_IO_DEBUG)
1026 dbg_msg("bad CRC at PEB %d, calculated %#08x, "
1027 "read %#08x", pnum, crc, hdr_crc);
Artem Bityutskiy92e1a7d2010-09-03 14:22:17 +03001028 if (!read_err)
1029 return UBI_IO_BAD_HDR;
1030 else
1031 return UBI_IO_BAD_HDR_EBADMSG;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001032 }
1033
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001034 err = validate_vid_hdr(ubi, vid_hdr);
1035 if (err) {
1036 ubi_err("validation failed for PEB %d", pnum);
1037 return -EINVAL;
1038 }
1039
1040 return read_err ? UBI_IO_BITFLIPS : 0;
1041}
1042
1043/**
1044 * ubi_io_write_vid_hdr - write a volume identifier header.
1045 * @ubi: UBI device description object
1046 * @pnum: the physical eraseblock number to write to
1047 * @vid_hdr: the volume identifier header to write
1048 *
1049 * This function writes the volume identifier header described by @vid_hdr to
1050 * physical eraseblock @pnum. This function automatically fills the
1051 * @vid_hdr->magic and the @vid_hdr->version fields, as well as calculates
1052 * header CRC checksum and stores it at vid_hdr->hdr_crc.
1053 *
1054 * This function returns zero in case of success and a negative error code in
1055 * case of failure. If %-EIO is returned, the physical eraseblock probably went
1056 * bad.
1057 */
Artem Bityutskiye88d6e102007-08-29 14:51:52 +03001058int ubi_io_write_vid_hdr(struct ubi_device *ubi, int pnum,
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001059 struct ubi_vid_hdr *vid_hdr)
1060{
1061 int err;
1062 uint32_t crc;
1063 void *p;
1064
1065 dbg_io("write VID header to PEB %d", pnum);
1066 ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
1067
1068 err = paranoid_check_peb_ec_hdr(ubi, pnum);
1069 if (err)
Artem Bityutskiyadbf05e2010-01-20 10:28:58 +02001070 return err;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001071
Christoph Hellwig3261ebd2007-05-21 17:41:46 +03001072 vid_hdr->magic = cpu_to_be32(UBI_VID_HDR_MAGIC);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001073 vid_hdr->version = UBI_VERSION;
1074 crc = crc32(UBI_CRC32_INIT, vid_hdr, UBI_VID_HDR_SIZE_CRC);
Christoph Hellwig3261ebd2007-05-21 17:41:46 +03001075 vid_hdr->hdr_crc = cpu_to_be32(crc);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001076
1077 err = paranoid_check_vid_hdr(ubi, pnum, vid_hdr);
1078 if (err)
Artem Bityutskiyadbf05e2010-01-20 10:28:58 +02001079 return err;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001080
1081 p = (char *)vid_hdr - ubi->vid_hdr_shift;
1082 err = ubi_io_write(ubi, p, pnum, ubi->vid_hdr_aloffset,
1083 ubi->vid_hdr_alsize);
1084 return err;
1085}
1086
1087#ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
1088
1089/**
1090 * paranoid_check_not_bad - ensure that a physical eraseblock is not bad.
1091 * @ubi: UBI device description object
1092 * @pnum: physical eraseblock number to check
1093 *
Artem Bityutskiyadbf05e2010-01-20 10:28:58 +02001094 * This function returns zero if the physical eraseblock is good, %-EINVAL if
1095 * it is bad and a negative error code if an error occurred.
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001096 */
1097static int paranoid_check_not_bad(const struct ubi_device *ubi, int pnum)
1098{
1099 int err;
1100
1101 err = ubi_io_is_bad(ubi, pnum);
1102 if (!err)
1103 return err;
1104
1105 ubi_err("paranoid check failed for PEB %d", pnum);
1106 ubi_dbg_dump_stack();
Artem Bityutskiyadbf05e2010-01-20 10:28:58 +02001107 return err > 0 ? -EINVAL : err;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001108}
1109
1110/**
1111 * paranoid_check_ec_hdr - check if an erase counter header is all right.
1112 * @ubi: UBI device description object
1113 * @pnum: physical eraseblock number the erase counter header belongs to
1114 * @ec_hdr: the erase counter header to check
1115 *
1116 * This function returns zero if the erase counter header contains valid
Artem Bityutskiyadbf05e2010-01-20 10:28:58 +02001117 * values, and %-EINVAL if not.
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001118 */
1119static int paranoid_check_ec_hdr(const struct ubi_device *ubi, int pnum,
1120 const struct ubi_ec_hdr *ec_hdr)
1121{
1122 int err;
1123 uint32_t magic;
1124
Christoph Hellwig3261ebd2007-05-21 17:41:46 +03001125 magic = be32_to_cpu(ec_hdr->magic);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001126 if (magic != UBI_EC_HDR_MAGIC) {
1127 ubi_err("bad magic %#08x, must be %#08x",
1128 magic, UBI_EC_HDR_MAGIC);
1129 goto fail;
1130 }
1131
1132 err = validate_ec_hdr(ubi, ec_hdr);
1133 if (err) {
1134 ubi_err("paranoid check failed for PEB %d", pnum);
1135 goto fail;
1136 }
1137
1138 return 0;
1139
1140fail:
1141 ubi_dbg_dump_ec_hdr(ec_hdr);
1142 ubi_dbg_dump_stack();
Artem Bityutskiyadbf05e2010-01-20 10:28:58 +02001143 return -EINVAL;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001144}
1145
1146/**
Artem Bityutskiyebaaf1a2008-07-18 13:34:32 +03001147 * paranoid_check_peb_ec_hdr - check erase counter header.
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001148 * @ubi: UBI device description object
1149 * @pnum: the physical eraseblock number to check
1150 *
Artem Bityutskiyadbf05e2010-01-20 10:28:58 +02001151 * This function returns zero if the erase counter header is all right and and
1152 * a negative error code if not or if an error occurred.
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001153 */
1154static int paranoid_check_peb_ec_hdr(const struct ubi_device *ubi, int pnum)
1155{
1156 int err;
1157 uint32_t crc, hdr_crc;
1158 struct ubi_ec_hdr *ec_hdr;
1159
Artem Bityutskiy33818bb2007-08-28 21:29:32 +03001160 ec_hdr = kzalloc(ubi->ec_hdr_alsize, GFP_NOFS);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001161 if (!ec_hdr)
1162 return -ENOMEM;
1163
1164 err = ubi_io_read(ubi, ec_hdr, pnum, 0, UBI_EC_HDR_SIZE);
1165 if (err && err != UBI_IO_BITFLIPS && err != -EBADMSG)
1166 goto exit;
1167
1168 crc = crc32(UBI_CRC32_INIT, ec_hdr, UBI_EC_HDR_SIZE_CRC);
Christoph Hellwig3261ebd2007-05-21 17:41:46 +03001169 hdr_crc = be32_to_cpu(ec_hdr->hdr_crc);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001170 if (hdr_crc != crc) {
1171 ubi_err("bad CRC, calculated %#08x, read %#08x", crc, hdr_crc);
1172 ubi_err("paranoid check failed for PEB %d", pnum);
1173 ubi_dbg_dump_ec_hdr(ec_hdr);
1174 ubi_dbg_dump_stack();
Artem Bityutskiyadbf05e2010-01-20 10:28:58 +02001175 err = -EINVAL;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001176 goto exit;
1177 }
1178
1179 err = paranoid_check_ec_hdr(ubi, pnum, ec_hdr);
1180
1181exit:
1182 kfree(ec_hdr);
1183 return err;
1184}
1185
1186/**
1187 * paranoid_check_vid_hdr - check that a volume identifier header is all right.
1188 * @ubi: UBI device description object
1189 * @pnum: physical eraseblock number the volume identifier header belongs to
1190 * @vid_hdr: the volume identifier header to check
1191 *
1192 * This function returns zero if the volume identifier header is all right, and
Artem Bityutskiyadbf05e2010-01-20 10:28:58 +02001193 * %-EINVAL if not.
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001194 */
1195static int paranoid_check_vid_hdr(const struct ubi_device *ubi, int pnum,
1196 const struct ubi_vid_hdr *vid_hdr)
1197{
1198 int err;
1199 uint32_t magic;
1200
Christoph Hellwig3261ebd2007-05-21 17:41:46 +03001201 magic = be32_to_cpu(vid_hdr->magic);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001202 if (magic != UBI_VID_HDR_MAGIC) {
1203 ubi_err("bad VID header magic %#08x at PEB %d, must be %#08x",
1204 magic, pnum, UBI_VID_HDR_MAGIC);
1205 goto fail;
1206 }
1207
1208 err = validate_vid_hdr(ubi, vid_hdr);
1209 if (err) {
1210 ubi_err("paranoid check failed for PEB %d", pnum);
1211 goto fail;
1212 }
1213
1214 return err;
1215
1216fail:
1217 ubi_err("paranoid check failed for PEB %d", pnum);
1218 ubi_dbg_dump_vid_hdr(vid_hdr);
1219 ubi_dbg_dump_stack();
Artem Bityutskiyadbf05e2010-01-20 10:28:58 +02001220 return -EINVAL;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001221
1222}
1223
1224/**
Artem Bityutskiyebaaf1a2008-07-18 13:34:32 +03001225 * paranoid_check_peb_vid_hdr - check volume identifier header.
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001226 * @ubi: UBI device description object
1227 * @pnum: the physical eraseblock number to check
1228 *
1229 * This function returns zero if the volume identifier header is all right,
Artem Bityutskiyadbf05e2010-01-20 10:28:58 +02001230 * and a negative error code if not or if an error occurred.
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001231 */
1232static int paranoid_check_peb_vid_hdr(const struct ubi_device *ubi, int pnum)
1233{
1234 int err;
1235 uint32_t crc, hdr_crc;
1236 struct ubi_vid_hdr *vid_hdr;
1237 void *p;
1238
Artem Bityutskiy33818bb2007-08-28 21:29:32 +03001239 vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001240 if (!vid_hdr)
1241 return -ENOMEM;
1242
1243 p = (char *)vid_hdr - ubi->vid_hdr_shift;
1244 err = ubi_io_read(ubi, p, pnum, ubi->vid_hdr_aloffset,
1245 ubi->vid_hdr_alsize);
1246 if (err && err != UBI_IO_BITFLIPS && err != -EBADMSG)
1247 goto exit;
1248
1249 crc = crc32(UBI_CRC32_INIT, vid_hdr, UBI_EC_HDR_SIZE_CRC);
Christoph Hellwig3261ebd2007-05-21 17:41:46 +03001250 hdr_crc = be32_to_cpu(vid_hdr->hdr_crc);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001251 if (hdr_crc != crc) {
1252 ubi_err("bad VID header CRC at PEB %d, calculated %#08x, "
1253 "read %#08x", pnum, crc, hdr_crc);
1254 ubi_err("paranoid check failed for PEB %d", pnum);
1255 ubi_dbg_dump_vid_hdr(vid_hdr);
1256 ubi_dbg_dump_stack();
Artem Bityutskiyadbf05e2010-01-20 10:28:58 +02001257 err = -EINVAL;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001258 goto exit;
1259 }
1260
1261 err = paranoid_check_vid_hdr(ubi, pnum, vid_hdr);
1262
1263exit:
1264 ubi_free_vid_hdr(ubi, vid_hdr);
1265 return err;
1266}
1267
1268/**
Artem Bityutskiy6e9065d2010-01-25 17:09:30 +02001269 * ubi_dbg_check_write - make sure write succeeded.
1270 * @ubi: UBI device description object
1271 * @buf: buffer with data which were written
1272 * @pnum: physical eraseblock number the data were written to
1273 * @offset: offset within the physical eraseblock the data were written to
1274 * @len: how many bytes were written
1275 *
1276 * This functions reads data which were recently written and compares it with
1277 * the original data buffer - the data have to match. Returns zero if the data
1278 * match and a negative error code if not or in case of failure.
1279 */
1280int ubi_dbg_check_write(struct ubi_device *ubi, const void *buf, int pnum,
1281 int offset, int len)
1282{
1283 int err, i;
1284
1285 mutex_lock(&ubi->dbg_buf_mutex);
1286 err = ubi_io_read(ubi, ubi->dbg_peb_buf, pnum, offset, len);
1287 if (err)
1288 goto out_unlock;
1289
1290 for (i = 0; i < len; i++) {
1291 uint8_t c = ((uint8_t *)buf)[i];
1292 uint8_t c1 = ((uint8_t *)ubi->dbg_peb_buf)[i];
1293 int dump_len;
1294
1295 if (c == c1)
1296 continue;
1297
1298 ubi_err("paranoid check failed for PEB %d:%d, len %d",
1299 pnum, offset, len);
1300 ubi_msg("data differ at position %d", i);
1301 dump_len = max_t(int, 128, len - i);
1302 ubi_msg("hex dump of the original buffer from %d to %d",
1303 i, i + dump_len);
1304 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1,
1305 buf + i, dump_len, 1);
1306 ubi_msg("hex dump of the read buffer from %d to %d",
1307 i, i + dump_len);
1308 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1,
1309 ubi->dbg_peb_buf + i, dump_len, 1);
1310 ubi_dbg_dump_stack();
1311 err = -EINVAL;
1312 goto out_unlock;
1313 }
1314 mutex_unlock(&ubi->dbg_buf_mutex);
1315
1316 return 0;
1317
1318out_unlock:
1319 mutex_unlock(&ubi->dbg_buf_mutex);
1320 return err;
1321}
1322
1323/**
Artem Bityutskiy40a71a82009-06-28 19:16:55 +03001324 * ubi_dbg_check_all_ff - check that a region of flash is empty.
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001325 * @ubi: UBI device description object
1326 * @pnum: the physical eraseblock number to check
1327 * @offset: the starting offset within the physical eraseblock to check
1328 * @len: the length of the region to check
1329 *
1330 * This function returns zero if only 0xFF bytes are present at offset
Artem Bityutskiyadbf05e2010-01-20 10:28:58 +02001331 * @offset of the physical eraseblock @pnum, and a negative error code if not
1332 * or if an error occurred.
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001333 */
Artem Bityutskiy40a71a82009-06-28 19:16:55 +03001334int ubi_dbg_check_all_ff(struct ubi_device *ubi, int pnum, int offset, int len)
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001335{
1336 size_t read;
1337 int err;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001338 loff_t addr = (loff_t)pnum * ubi->peb_size + offset;
1339
Artem Bityutskiye88d6e102007-08-29 14:51:52 +03001340 mutex_lock(&ubi->dbg_buf_mutex);
1341 err = ubi->mtd->read(ubi->mtd, addr, len, &read, ubi->dbg_peb_buf);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001342 if (err && err != -EUCLEAN) {
1343 ubi_err("error %d while reading %d bytes from PEB %d:%d, "
1344 "read %zd bytes", err, len, pnum, offset, read);
1345 goto error;
1346 }
1347
Artem Bityutskiybb00e182010-07-31 09:37:34 +03001348 err = ubi_check_pattern(ubi->dbg_peb_buf, 0xFF, len);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001349 if (err == 0) {
1350 ubi_err("flash region at PEB %d:%d, length %d does not "
1351 "contain all 0xFF bytes", pnum, offset, len);
1352 goto fail;
1353 }
Artem Bityutskiye88d6e102007-08-29 14:51:52 +03001354 mutex_unlock(&ubi->dbg_buf_mutex);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001355
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001356 return 0;
1357
1358fail:
1359 ubi_err("paranoid check failed for PEB %d", pnum);
Artem Bityutskiyc8566352008-07-16 17:40:22 +03001360 ubi_msg("hex dump of the %d-%d region", offset, offset + len);
Artem Bityutskiy69866462007-08-29 14:56:20 +03001361 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 32, 1,
Artem Bityutskiye88d6e102007-08-29 14:51:52 +03001362 ubi->dbg_peb_buf, len, 1);
Artem Bityutskiyadbf05e2010-01-20 10:28:58 +02001363 err = -EINVAL;
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001364error:
1365 ubi_dbg_dump_stack();
Artem Bityutskiye88d6e102007-08-29 14:51:52 +03001366 mutex_unlock(&ubi->dbg_buf_mutex);
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001367 return err;
1368}
1369
Artem B. Bityutskiy801c1352006-06-27 12:22:22 +04001370#endif /* CONFIG_MTD_UBI_DEBUG_PARANOID */