1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2006-2008 Nokia Corporation
4 *
5 * Test OOB read and write on MTD device.
6 *
7 * Author: Adrian Hunter <ext-adrian.hunter@nokia.com>
8 */
9
10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11
12 #include <asm/div64.h>
13 #include <linux/init.h>
14 #include <linux/module.h>
15 #include <linux/moduleparam.h>
16 #include <linux/err.h>
17 #include <linux/mtd/mtd.h>
18 #include <linux/slab.h>
19 #include <linux/sched.h>
20 #include <linux/random.h>
21
22 #include "mtd_test.h"
23
24 static int dev = -EINVAL;
25 static int bitflip_limit;
26 module_param(dev, int, S_IRUGO);
27 MODULE_PARM_DESC(dev, "MTD device number to use");
28 module_param(bitflip_limit, int, S_IRUGO);
29 MODULE_PARM_DESC(bitflip_limit, "Max. allowed bitflips per page");
30
31 static struct mtd_info *mtd;
32 static unsigned char *readbuf;
33 static unsigned char *writebuf;
34 static unsigned char *bbt;
35
36 static int ebcnt;
37 static int pgcnt;
38 static int errcnt;
39 static int use_offset;
40 static int use_len;
41 static int use_len_max;
42 static int vary_offset;
43 static struct rnd_state rnd_state;
44
do_vary_offset(void)45 static void do_vary_offset(void)
46 {
47 use_len -= 1;
48 if (use_len < 1) {
49 use_offset += 1;
50 if (use_offset >= use_len_max)
51 use_offset = 0;
52 use_len = use_len_max - use_offset;
53 }
54 }
55
write_eraseblock(int ebnum)56 static int write_eraseblock(int ebnum)
57 {
58 int i;
59 struct mtd_oob_ops ops = { };
60 int err = 0;
61 loff_t addr = (loff_t)ebnum * mtd->erasesize;
62
63 prandom_bytes_state(&rnd_state, writebuf, use_len_max * pgcnt);
64 for (i = 0; i < pgcnt; ++i, addr += mtd->writesize) {
65 ops.mode = MTD_OPS_AUTO_OOB;
66 ops.len = 0;
67 ops.retlen = 0;
68 ops.ooblen = use_len;
69 ops.oobretlen = 0;
70 ops.ooboffs = use_offset;
71 ops.datbuf = NULL;
72 ops.oobbuf = writebuf + (use_len_max * i) + use_offset;
73 err = mtd_write_oob(mtd, addr, &ops);
74 if (err || ops.oobretlen != use_len) {
75 pr_err("error: writeoob failed at %#llx\n",
76 (long long)addr);
77 pr_err("error: use_len %d, use_offset %d\n",
78 use_len, use_offset);
79 errcnt += 1;
80 return err ? err : -1;
81 }
82 if (vary_offset)
83 do_vary_offset();
84 }
85
86 return err;
87 }
88
write_whole_device(void)89 static int write_whole_device(void)
90 {
91 int err;
92 unsigned int i;
93
94 pr_info("writing OOBs of whole device\n");
95 for (i = 0; i < ebcnt; ++i) {
96 if (bbt[i])
97 continue;
98 err = write_eraseblock(i);
99 if (err)
100 return err;
101 if (i % 256 == 0)
102 pr_info("written up to eraseblock %u\n", i);
103
104 err = mtdtest_relax();
105 if (err)
106 return err;
107 }
108 pr_info("written %u eraseblocks\n", i);
109 return 0;
110 }
111
112 /*
113 * Display the address, offset and data bytes at comparison failure.
114 * Return number of bitflips encountered.
115 */
memcmpshowoffset(loff_t addr,loff_t offset,const void * cs,const void * ct,size_t count)116 static size_t memcmpshowoffset(loff_t addr, loff_t offset, const void *cs,
117 const void *ct, size_t count)
118 {
119 const unsigned char *su1, *su2;
120 int res;
121 size_t i = 0;
122 size_t bitflips = 0;
123
124 for (su1 = cs, su2 = ct; 0 < count; ++su1, ++su2, count--, i++) {
125 res = *su1 ^ *su2;
126 if (res) {
127 pr_info("error @addr[0x%lx:0x%lx] 0x%x -> 0x%x diff 0x%x\n",
128 (unsigned long)addr, (unsigned long)offset + i,
129 *su1, *su2, res);
130 bitflips += hweight8(res);
131 }
132 }
133
134 return bitflips;
135 }
136
137 #define memcmpshow(addr, cs, ct, count) memcmpshowoffset((addr), 0, (cs), (ct),\
138 (count))
139
140 /*
141 * Compare with 0xff and show the address, offset and data bytes at
142 * comparison failure. Return number of bitflips encountered.
143 */
memffshow(loff_t addr,loff_t offset,const void * cs,size_t count)144 static size_t memffshow(loff_t addr, loff_t offset, const void *cs,
145 size_t count)
146 {
147 const unsigned char *su1;
148 int res;
149 size_t i = 0;
150 size_t bitflips = 0;
151
152 for (su1 = cs; 0 < count; ++su1, count--, i++) {
153 res = *su1 ^ 0xff;
154 if (res) {
155 pr_info("error @addr[0x%lx:0x%lx] 0x%x -> 0xff diff 0x%x\n",
156 (unsigned long)addr, (unsigned long)offset + i,
157 *su1, res);
158 bitflips += hweight8(res);
159 }
160 }
161
162 return bitflips;
163 }
164
verify_eraseblock(int ebnum)165 static int verify_eraseblock(int ebnum)
166 {
167 int i;
168 struct mtd_oob_ops ops = { };
169 int err = 0;
170 loff_t addr = (loff_t)ebnum * mtd->erasesize;
171 size_t bitflips;
172
173 prandom_bytes_state(&rnd_state, writebuf, use_len_max * pgcnt);
174 for (i = 0; i < pgcnt; ++i, addr += mtd->writesize) {
175 ops.mode = MTD_OPS_AUTO_OOB;
176 ops.len = 0;
177 ops.retlen = 0;
178 ops.ooblen = use_len;
179 ops.oobretlen = 0;
180 ops.ooboffs = use_offset;
181 ops.datbuf = NULL;
182 ops.oobbuf = readbuf;
183 err = mtd_read_oob(mtd, addr, &ops);
184 if (mtd_is_bitflip(err))
185 err = 0;
186
187 if (err || ops.oobretlen != use_len) {
188 pr_err("error: readoob failed at %#llx\n",
189 (long long)addr);
190 errcnt += 1;
191 return err ? err : -1;
192 }
193
194 bitflips = memcmpshow(addr, readbuf,
195 writebuf + (use_len_max * i) + use_offset,
196 use_len);
197 if (bitflips > bitflip_limit) {
198 pr_err("error: verify failed at %#llx\n",
199 (long long)addr);
200 errcnt += 1;
201 if (errcnt > 1000) {
202 pr_err("error: too many errors\n");
203 return -1;
204 }
205 } else if (bitflips) {
206 pr_info("ignoring error as within bitflip_limit\n");
207 }
208
209 if (use_offset != 0 || use_len < mtd->oobavail) {
210 int k;
211
212 ops.mode = MTD_OPS_AUTO_OOB;
213 ops.len = 0;
214 ops.retlen = 0;
215 ops.ooblen = mtd->oobavail;
216 ops.oobretlen = 0;
217 ops.ooboffs = 0;
218 ops.datbuf = NULL;
219 ops.oobbuf = readbuf;
220 err = mtd_read_oob(mtd, addr, &ops);
221 if (mtd_is_bitflip(err))
222 err = 0;
223
224 if (err || ops.oobretlen != mtd->oobavail) {
225 pr_err("error: readoob failed at %#llx\n",
226 (long long)addr);
227 errcnt += 1;
228 return err ? err : -1;
229 }
230 bitflips = memcmpshowoffset(addr, use_offset,
231 readbuf + use_offset,
232 writebuf + (use_len_max * i) + use_offset,
233 use_len);
234
235 /* verify pre-offset area for 0xff */
236 bitflips += memffshow(addr, 0, readbuf, use_offset);
237
238 /* verify post-(use_offset + use_len) area for 0xff */
239 k = use_offset + use_len;
240 bitflips += memffshow(addr, k, readbuf + k,
241 mtd->oobavail - k);
242
243 if (bitflips > bitflip_limit) {
244 pr_err("error: verify failed at %#llx\n",
245 (long long)addr);
246 errcnt += 1;
247 if (errcnt > 1000) {
248 pr_err("error: too many errors\n");
249 return -1;
250 }
251 } else if (bitflips) {
252 pr_info("ignoring errors as within bitflip limit\n");
253 }
254 }
255 if (vary_offset)
256 do_vary_offset();
257 }
258 return err;
259 }
260
verify_eraseblock_in_one_go(int ebnum)261 static int verify_eraseblock_in_one_go(int ebnum)
262 {
263 struct mtd_oob_ops ops = { };
264 int err = 0;
265 loff_t addr = (loff_t)ebnum * mtd->erasesize;
266 size_t len = mtd->oobavail * pgcnt;
267 size_t oobavail = mtd->oobavail;
268 size_t bitflips;
269 int i;
270
271 prandom_bytes_state(&rnd_state, writebuf, len);
272 ops.mode = MTD_OPS_AUTO_OOB;
273 ops.len = 0;
274 ops.retlen = 0;
275 ops.ooblen = len;
276 ops.oobretlen = 0;
277 ops.ooboffs = 0;
278 ops.datbuf = NULL;
279 ops.oobbuf = readbuf;
280
281 /* read entire block's OOB at one go */
282 err = mtd_read_oob(mtd, addr, &ops);
283 if (mtd_is_bitflip(err))
284 err = 0;
285
286 if (err || ops.oobretlen != len) {
287 pr_err("error: readoob failed at %#llx\n",
288 (long long)addr);
289 errcnt += 1;
290 return err ? err : -1;
291 }
292
293 /* verify one page OOB at a time for bitflip per page limit check */
294 for (i = 0; i < pgcnt; ++i, addr += mtd->writesize) {
295 bitflips = memcmpshow(addr, readbuf + (i * oobavail),
296 writebuf + (i * oobavail), oobavail);
297 if (bitflips > bitflip_limit) {
298 pr_err("error: verify failed at %#llx\n",
299 (long long)addr);
300 errcnt += 1;
301 if (errcnt > 1000) {
302 pr_err("error: too many errors\n");
303 return -1;
304 }
305 } else if (bitflips) {
306 pr_info("ignoring error as within bitflip_limit\n");
307 }
308 }
309
310 return err;
311 }
312
verify_all_eraseblocks(void)313 static int verify_all_eraseblocks(void)
314 {
315 int err;
316 unsigned int i;
317
318 pr_info("verifying all eraseblocks\n");
319 for (i = 0; i < ebcnt; ++i) {
320 if (bbt[i])
321 continue;
322 err = verify_eraseblock(i);
323 if (err)
324 return err;
325 if (i % 256 == 0)
326 pr_info("verified up to eraseblock %u\n", i);
327
328 err = mtdtest_relax();
329 if (err)
330 return err;
331 }
332 pr_info("verified %u eraseblocks\n", i);
333 return 0;
334 }
335
mtd_oobtest_init(void)336 static int __init mtd_oobtest_init(void)
337 {
338 int err = 0;
339 unsigned int i;
340 uint64_t tmp;
341 struct mtd_oob_ops ops = { };
342 loff_t addr = 0, addr0;
343
344 printk(KERN_INFO "\n");
345 printk(KERN_INFO "=================================================\n");
346
347 if (dev < 0) {
348 pr_info("Please specify a valid mtd-device via module parameter\n");
349 pr_crit("CAREFUL: This test wipes all data on the specified MTD device!\n");
350 return -EINVAL;
351 }
352
353 pr_info("MTD device: %d\n", dev);
354
355 mtd = get_mtd_device(NULL, dev);
356 if (IS_ERR(mtd)) {
357 err = PTR_ERR(mtd);
358 pr_err("error: cannot get MTD device\n");
359 return err;
360 }
361
362 if (!mtd_type_is_nand(mtd)) {
363 pr_info("this test requires NAND flash\n");
364 goto out;
365 }
366
367 tmp = mtd->size;
368 do_div(tmp, mtd->erasesize);
369 ebcnt = tmp;
370 pgcnt = mtd->erasesize / mtd->writesize;
371
372 pr_info("MTD device size %llu, eraseblock size %u, "
373 "page size %u, count of eraseblocks %u, pages per "
374 "eraseblock %u, OOB size %u\n",
375 (unsigned long long)mtd->size, mtd->erasesize,
376 mtd->writesize, ebcnt, pgcnt, mtd->oobsize);
377
378 err = -ENOMEM;
379 readbuf = kmalloc(mtd->erasesize, GFP_KERNEL);
380 if (!readbuf)
381 goto out;
382 writebuf = kmalloc(mtd->erasesize, GFP_KERNEL);
383 if (!writebuf)
384 goto out;
385 bbt = kzalloc(ebcnt, GFP_KERNEL);
386 if (!bbt)
387 goto out;
388
389 err = mtdtest_scan_for_bad_eraseblocks(mtd, bbt, 0, ebcnt);
390 if (err)
391 goto out;
392
393 use_offset = 0;
394 use_len = mtd->oobavail;
395 use_len_max = mtd->oobavail;
396 vary_offset = 0;
397
398 /* First test: write all OOB, read it back and verify */
399 pr_info("test 1 of 5\n");
400
401 err = mtdtest_erase_good_eraseblocks(mtd, bbt, 0, ebcnt);
402 if (err)
403 goto out;
404
405 prandom_seed_state(&rnd_state, 1);
406 err = write_whole_device();
407 if (err)
408 goto out;
409
410 prandom_seed_state(&rnd_state, 1);
411 err = verify_all_eraseblocks();
412 if (err)
413 goto out;
414
415 /*
416 * Second test: write all OOB, a block at a time, read it back and
417 * verify.
418 */
419 pr_info("test 2 of 5\n");
420
421 err = mtdtest_erase_good_eraseblocks(mtd, bbt, 0, ebcnt);
422 if (err)
423 goto out;
424
425 prandom_seed_state(&rnd_state, 3);
426 err = write_whole_device();
427 if (err)
428 goto out;
429
430 /* Check all eraseblocks */
431 prandom_seed_state(&rnd_state, 3);
432 pr_info("verifying all eraseblocks\n");
433 for (i = 0; i < ebcnt; ++i) {
434 if (bbt[i])
435 continue;
436 err = verify_eraseblock_in_one_go(i);
437 if (err)
438 goto out;
439 if (i % 256 == 0)
440 pr_info("verified up to eraseblock %u\n", i);
441
442 err = mtdtest_relax();
443 if (err)
444 goto out;
445 }
446 pr_info("verified %u eraseblocks\n", i);
447
448 /*
449 * Third test: write OOB at varying offsets and lengths, read it back
450 * and verify.
451 */
452 pr_info("test 3 of 5\n");
453
454 err = mtdtest_erase_good_eraseblocks(mtd, bbt, 0, ebcnt);
455 if (err)
456 goto out;
457
458 /* Write all eraseblocks */
459 use_offset = 0;
460 use_len = mtd->oobavail;
461 use_len_max = mtd->oobavail;
462 vary_offset = 1;
463 prandom_seed_state(&rnd_state, 5);
464
465 err = write_whole_device();
466 if (err)
467 goto out;
468
469 /* Check all eraseblocks */
470 use_offset = 0;
471 use_len = mtd->oobavail;
472 use_len_max = mtd->oobavail;
473 vary_offset = 1;
474 prandom_seed_state(&rnd_state, 5);
475 err = verify_all_eraseblocks();
476 if (err)
477 goto out;
478
479 use_offset = 0;
480 use_len = mtd->oobavail;
481 use_len_max = mtd->oobavail;
482 vary_offset = 0;
483
484 /* Fourth test: try to write off end of device */
485 pr_info("test 4 of 5\n");
486
487 err = mtdtest_erase_good_eraseblocks(mtd, bbt, 0, ebcnt);
488 if (err)
489 goto out;
490
491 addr0 = 0;
492 for (i = 0; i < ebcnt && bbt[i]; ++i)
493 addr0 += mtd->erasesize;
494
495 /* Attempt to write off end of OOB */
496 ops.mode = MTD_OPS_AUTO_OOB;
497 ops.len = 0;
498 ops.retlen = 0;
499 ops.ooblen = 1;
500 ops.oobretlen = 0;
501 ops.ooboffs = mtd->oobavail;
502 ops.datbuf = NULL;
503 ops.oobbuf = writebuf;
504 pr_info("attempting to start write past end of OOB\n");
505 pr_info("an error is expected...\n");
506 err = mtd_write_oob(mtd, addr0, &ops);
507 if (err) {
508 pr_info("error occurred as expected\n");
509 } else {
510 pr_err("error: can write past end of OOB\n");
511 errcnt += 1;
512 }
513
514 /* Attempt to read off end of OOB */
515 ops.mode = MTD_OPS_AUTO_OOB;
516 ops.len = 0;
517 ops.retlen = 0;
518 ops.ooblen = 1;
519 ops.oobretlen = 0;
520 ops.ooboffs = mtd->oobavail;
521 ops.datbuf = NULL;
522 ops.oobbuf = readbuf;
523 pr_info("attempting to start read past end of OOB\n");
524 pr_info("an error is expected...\n");
525 err = mtd_read_oob(mtd, addr0, &ops);
526 if (mtd_is_bitflip(err))
527 err = 0;
528
529 if (err) {
530 pr_info("error occurred as expected\n");
531 } else {
532 pr_err("error: can read past end of OOB\n");
533 errcnt += 1;
534 }
535
536 if (bbt[ebcnt - 1])
537 pr_info("skipping end of device tests because last "
538 "block is bad\n");
539 else {
540 /* Attempt to write off end of device */
541 ops.mode = MTD_OPS_AUTO_OOB;
542 ops.len = 0;
543 ops.retlen = 0;
544 ops.ooblen = mtd->oobavail + 1;
545 ops.oobretlen = 0;
546 ops.ooboffs = 0;
547 ops.datbuf = NULL;
548 ops.oobbuf = writebuf;
549 pr_info("attempting to write past end of device\n");
550 pr_info("an error is expected...\n");
551 err = mtd_write_oob(mtd, mtd->size - mtd->writesize, &ops);
552 if (err) {
553 pr_info("error occurred as expected\n");
554 } else {
555 pr_err("error: wrote past end of device\n");
556 errcnt += 1;
557 }
558
559 /* Attempt to read off end of device */
560 ops.mode = MTD_OPS_AUTO_OOB;
561 ops.len = 0;
562 ops.retlen = 0;
563 ops.ooblen = mtd->oobavail + 1;
564 ops.oobretlen = 0;
565 ops.ooboffs = 0;
566 ops.datbuf = NULL;
567 ops.oobbuf = readbuf;
568 pr_info("attempting to read past end of device\n");
569 pr_info("an error is expected...\n");
570 err = mtd_read_oob(mtd, mtd->size - mtd->writesize, &ops);
571 if (mtd_is_bitflip(err))
572 err = 0;
573
574 if (err) {
575 pr_info("error occurred as expected\n");
576 } else {
577 pr_err("error: read past end of device\n");
578 errcnt += 1;
579 }
580
581 err = mtdtest_erase_eraseblock(mtd, ebcnt - 1);
582 if (err)
583 goto out;
584
585 /* Attempt to write off end of device */
586 ops.mode = MTD_OPS_AUTO_OOB;
587 ops.len = 0;
588 ops.retlen = 0;
589 ops.ooblen = mtd->oobavail;
590 ops.oobretlen = 0;
591 ops.ooboffs = 1;
592 ops.datbuf = NULL;
593 ops.oobbuf = writebuf;
594 pr_info("attempting to write past end of device\n");
595 pr_info("an error is expected...\n");
596 err = mtd_write_oob(mtd, mtd->size - mtd->writesize, &ops);
597 if (err) {
598 pr_info("error occurred as expected\n");
599 } else {
600 pr_err("error: wrote past end of device\n");
601 errcnt += 1;
602 }
603
604 /* Attempt to read off end of device */
605 ops.mode = MTD_OPS_AUTO_OOB;
606 ops.len = 0;
607 ops.retlen = 0;
608 ops.ooblen = mtd->oobavail;
609 ops.oobretlen = 0;
610 ops.ooboffs = 1;
611 ops.datbuf = NULL;
612 ops.oobbuf = readbuf;
613 pr_info("attempting to read past end of device\n");
614 pr_info("an error is expected...\n");
615 err = mtd_read_oob(mtd, mtd->size - mtd->writesize, &ops);
616 if (mtd_is_bitflip(err))
617 err = 0;
618
619 if (err) {
620 pr_info("error occurred as expected\n");
621 } else {
622 pr_err("error: read past end of device\n");
623 errcnt += 1;
624 }
625 }
626
627 /* Fifth test: write / read across block boundaries */
628 pr_info("test 5 of 5\n");
629
630 /* Erase all eraseblocks */
631 err = mtdtest_erase_good_eraseblocks(mtd, bbt, 0, ebcnt);
632 if (err)
633 goto out;
634
635 /* Write all eraseblocks */
636 prandom_seed_state(&rnd_state, 11);
637 pr_info("writing OOBs of whole device\n");
638 for (i = 0; i < ebcnt - 1; ++i) {
639 int cnt = 2;
640 int pg;
641 size_t sz = mtd->oobavail;
642 if (bbt[i] || bbt[i + 1])
643 continue;
644 addr = (loff_t)(i + 1) * mtd->erasesize - mtd->writesize;
645 prandom_bytes_state(&rnd_state, writebuf, sz * cnt);
646 for (pg = 0; pg < cnt; ++pg) {
647 ops.mode = MTD_OPS_AUTO_OOB;
648 ops.len = 0;
649 ops.retlen = 0;
650 ops.ooblen = sz;
651 ops.oobretlen = 0;
652 ops.ooboffs = 0;
653 ops.datbuf = NULL;
654 ops.oobbuf = writebuf + pg * sz;
655 err = mtd_write_oob(mtd, addr, &ops);
656 if (err)
657 goto out;
658 if (i % 256 == 0)
659 pr_info("written up to eraseblock %u\n", i);
660
661 err = mtdtest_relax();
662 if (err)
663 goto out;
664
665 addr += mtd->writesize;
666 }
667 }
668 pr_info("written %u eraseblocks\n", i);
669
670 /* Check all eraseblocks */
671 prandom_seed_state(&rnd_state, 11);
672 pr_info("verifying all eraseblocks\n");
673 for (i = 0; i < ebcnt - 1; ++i) {
674 if (bbt[i] || bbt[i + 1])
675 continue;
676 prandom_bytes_state(&rnd_state, writebuf, mtd->oobavail * 2);
677 addr = (loff_t)(i + 1) * mtd->erasesize - mtd->writesize;
678 ops.mode = MTD_OPS_AUTO_OOB;
679 ops.len = 0;
680 ops.retlen = 0;
681 ops.ooblen = mtd->oobavail * 2;
682 ops.oobretlen = 0;
683 ops.ooboffs = 0;
684 ops.datbuf = NULL;
685 ops.oobbuf = readbuf;
686 err = mtd_read_oob(mtd, addr, &ops);
687 if (mtd_is_bitflip(err))
688 err = 0;
689
690 if (err)
691 goto out;
692 if (memcmpshow(addr, readbuf, writebuf,
693 mtd->oobavail * 2)) {
694 pr_err("error: verify failed at %#llx\n",
695 (long long)addr);
696 errcnt += 1;
697 if (errcnt > 1000) {
698 err = -EINVAL;
699 pr_err("error: too many errors\n");
700 goto out;
701 }
702 }
703 if (i % 256 == 0)
704 pr_info("verified up to eraseblock %u\n", i);
705
706 err = mtdtest_relax();
707 if (err)
708 goto out;
709 }
710 pr_info("verified %u eraseblocks\n", i);
711
712 pr_info("finished with %d errors\n", errcnt);
713 out:
714 kfree(bbt);
715 kfree(writebuf);
716 kfree(readbuf);
717 put_mtd_device(mtd);
718 if (err)
719 pr_info("error %d occurred\n", err);
720 printk(KERN_INFO "=================================================\n");
721 return err;
722 }
723 module_init(mtd_oobtest_init);
724
mtd_oobtest_exit(void)725 static void __exit mtd_oobtest_exit(void)
726 {
727 return;
728 }
729 module_exit(mtd_oobtest_exit);
730
731 MODULE_DESCRIPTION("Out-of-band test module");
732 MODULE_AUTHOR("Adrian Hunter");
733 MODULE_LICENSE("GPL");
734