1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2006-2008 Artem Bityutskiy
4 * Copyright (C) 2006-2008 Jarkko Lavinen
5 * Copyright (C) 2006-2008 Adrian Hunter
6 *
7 * Authors: Artem Bityutskiy, Jarkko Lavinen, Adria Hunter
8 *
9 * WARNING: this test program may kill your flash and your device. Do not
10 * use it unless you know what you do. Authors are not responsible for any
11 * damage caused by this program.
12 */
13
14#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
15
16#include <linux/init.h>
17#include <linux/ktime.h>
18#include <linux/module.h>
19#include <linux/moduleparam.h>
20#include <linux/err.h>
21#include <linux/mtd/mtd.h>
22#include <linux/slab.h>
23#include <linux/sched.h>
24#include "mtd_test.h"
25
26#define RETRIES 3
27
28static int eb = 8;
29module_param(eb, int, S_IRUGO);
30MODULE_PARM_DESC(eb, "eraseblock number within the selected MTD device");
31
32static int ebcnt = 32;
33module_param(ebcnt, int, S_IRUGO);
34MODULE_PARM_DESC(ebcnt, "number of consecutive eraseblocks to torture");
35
36static int pgcnt;
37module_param(pgcnt, int, S_IRUGO);
38MODULE_PARM_DESC(pgcnt, "number of pages per eraseblock to torture (0 => all)");
39
40static int dev = -EINVAL;
41module_param(dev, int, S_IRUGO);
42MODULE_PARM_DESC(dev, "MTD device number to use");
43
44static int gran = 512;
45module_param(gran, int, S_IRUGO);
46MODULE_PARM_DESC(gran, "how often the status information should be printed");
47
48static int check = 1;
49module_param(check, int, S_IRUGO);
50MODULE_PARM_DESC(check, "if the written data should be checked");
51
52static unsigned int cycles_count;
53module_param(cycles_count, uint, S_IRUGO);
54MODULE_PARM_DESC(cycles_count, "how many erase cycles to do "
55			       "(infinite by default)");
56
57static struct mtd_info *mtd;
58
59/* This buffer contains 0x555555...0xAAAAAA... pattern */
60static unsigned char *patt_5A5;
61/* This buffer contains 0xAAAAAA...0x555555... pattern */
62static unsigned char *patt_A5A;
63/* This buffer contains all 0xFF bytes */
64static unsigned char *patt_FF;
65/* This a temporary buffer is use when checking data */
66static unsigned char *check_buf;
67/* How many erase cycles were done */
68static unsigned int erase_cycles;
69
70static int pgsize;
71static ktime_t start, finish;
72
73static void report_corrupt(unsigned char *read, unsigned char *written);
74
75static inline void start_timing(void)
76{
77	start = ktime_get();
78}
79
80static inline void stop_timing(void)
81{
82	finish = ktime_get();
83}
84
85/*
86 * Check that the contents of eraseblock number @enbum is equivalent to the
87 * @buf buffer.
88 */
89static inline int check_eraseblock(int ebnum, unsigned char *buf)
90{
91	int err, retries = 0;
92	size_t read;
93	loff_t addr = (loff_t)ebnum * mtd->erasesize;
94	size_t len = mtd->erasesize;
95
96	if (pgcnt) {
97		addr = (loff_t)(ebnum + 1) * mtd->erasesize - pgcnt * pgsize;
98		len = pgcnt * pgsize;
99	}
100
101retry:
102	err = mtd_read(mtd, addr, len, &read, check_buf);
103	if (mtd_is_bitflip(err))
104		pr_err("single bit flip occurred at EB %d "
105		       "MTD reported that it was fixed.\n", ebnum);
106	else if (err) {
107		pr_err("error %d while reading EB %d, "
108		       "read %zd\n", err, ebnum, read);
109		return err;
110	}
111
112	if (read != len) {
113		pr_err("failed to read %zd bytes from EB %d, "
114		       "read only %zd, but no error reported\n",
115		       len, ebnum, read);
116		return -EIO;
117	}
118
119	if (memcmp(buf, check_buf, len)) {
120		pr_err("read wrong data from EB %d\n", ebnum);
121		report_corrupt(check_buf, buf);
122
123		if (retries++ < RETRIES) {
124			/* Try read again */
125			yield();
126			pr_info("re-try reading data from EB %d\n",
127			       ebnum);
128			goto retry;
129		} else {
130			pr_info("retried %d times, still errors, "
131			       "give-up\n", RETRIES);
132			return -EINVAL;
133		}
134	}
135
136	if (retries != 0)
137		pr_info("only attempt number %d was OK (!!!)\n",
138		       retries);
139
140	return 0;
141}
142
143static inline int write_pattern(int ebnum, void *buf)
144{
145	int err;
146	size_t written;
147	loff_t addr = (loff_t)ebnum * mtd->erasesize;
148	size_t len = mtd->erasesize;
149
150	if (pgcnt) {
151		addr = (loff_t)(ebnum + 1) * mtd->erasesize - pgcnt * pgsize;
152		len = pgcnt * pgsize;
153	}
154	err = mtd_write(mtd, addr, len, &written, buf);
155	if (err) {
156		pr_err("error %d while writing EB %d, written %zd"
157		      " bytes\n", err, ebnum, written);
158		return err;
159	}
160	if (written != len) {
161		pr_info("written only %zd bytes of %zd, but no error"
162		       " reported\n", written, len);
163		return -EIO;
164	}
165
166	return 0;
167}
168
169static int __init tort_init(void)
170{
171	int err = 0, i, infinite = !cycles_count;
172	unsigned char *bad_ebs;
173
174	printk(KERN_INFO "\n");
175	printk(KERN_INFO "=================================================\n");
176	pr_info("Warning: this program is trying to wear out your "
177	       "flash, stop it if this is not wanted.\n");
178
179	if (dev < 0) {
180		pr_info("Please specify a valid mtd-device via module parameter\n");
181		pr_crit("CAREFUL: This test wipes all data on the specified MTD device!\n");
182		return -EINVAL;
183	}
184
185	pr_info("MTD device: %d\n", dev);
186	pr_info("torture %d eraseblocks (%d-%d) of mtd%d\n",
187	       ebcnt, eb, eb + ebcnt - 1, dev);
188	if (pgcnt)
189		pr_info("torturing just %d pages per eraseblock\n",
190			pgcnt);
191	pr_info("write verify %s\n", check ? "enabled" : "disabled");
192
193	mtd = get_mtd_device(NULL, dev);
194	if (IS_ERR(mtd)) {
195		err = PTR_ERR(mtd);
196		pr_err("error: cannot get MTD device\n");
197		return err;
198	}
199
200	if (mtd->writesize == 1) {
201		pr_info("not NAND flash, assume page size is 512 "
202		       "bytes.\n");
203		pgsize = 512;
204	} else
205		pgsize = mtd->writesize;
206
207	if (pgcnt && (pgcnt > mtd->erasesize / pgsize || pgcnt < 0)) {
208		pr_err("error: invalid pgcnt value %d\n", pgcnt);
209		goto out_mtd;
210	}
211
212	err = -ENOMEM;
213	patt_5A5 = kmalloc(mtd->erasesize, GFP_KERNEL);
214	if (!patt_5A5)
215		goto out_mtd;
216
217	patt_A5A = kmalloc(mtd->erasesize, GFP_KERNEL);
218	if (!patt_A5A)
219		goto out_patt_5A5;
220
221	patt_FF = kmalloc(mtd->erasesize, GFP_KERNEL);
222	if (!patt_FF)
223		goto out_patt_A5A;
224
225	check_buf = kmalloc(mtd->erasesize, GFP_KERNEL);
226	if (!check_buf)
227		goto out_patt_FF;
228
229	bad_ebs = kzalloc(ebcnt, GFP_KERNEL);
230	if (!bad_ebs)
231		goto out_check_buf;
232
233	/* Initialize patterns */
234	memset(patt_FF, 0xFF, mtd->erasesize);
235	for (i = 0; i < mtd->erasesize / pgsize; i++) {
236		if (!(i & 1)) {
237			memset(patt_5A5 + i * pgsize, 0x55, pgsize);
238			memset(patt_A5A + i * pgsize, 0xAA, pgsize);
239		} else {
240			memset(patt_5A5 + i * pgsize, 0xAA, pgsize);
241			memset(patt_A5A + i * pgsize, 0x55, pgsize);
242		}
243	}
244
245	err = mtdtest_scan_for_bad_eraseblocks(mtd, bad_ebs, eb, ebcnt);
246	if (err)
247		goto out;
248
249	start_timing();
250	while (1) {
251		int i;
252		void *patt;
253
254		err = mtdtest_erase_good_eraseblocks(mtd, bad_ebs, eb, ebcnt);
255		if (err)
256			goto out;
257
258		/* Check if the eraseblocks contain only 0xFF bytes */
259		if (check) {
260			for (i = eb; i < eb + ebcnt; i++) {
261				if (bad_ebs[i - eb])
262					continue;
263				err = check_eraseblock(i, patt_FF);
264				if (err) {
265					pr_info("verify failed"
266					       " for 0xFF... pattern\n");
267					goto out;
268				}
269
270				err = mtdtest_relax();
271				if (err)
272					goto out;
273			}
274		}
275
276		/* Write the pattern */
277		for (i = eb; i < eb + ebcnt; i++) {
278			if (bad_ebs[i - eb])
279				continue;
280			if ((eb + erase_cycles) & 1)
281				patt = patt_5A5;
282			else
283				patt = patt_A5A;
284			err = write_pattern(i, patt);
285			if (err)
286				goto out;
287
288			err = mtdtest_relax();
289			if (err)
290				goto out;
291		}
292
293		/* Verify what we wrote */
294		if (check) {
295			for (i = eb; i < eb + ebcnt; i++) {
296				if (bad_ebs[i - eb])
297					continue;
298				if ((eb + erase_cycles) & 1)
299					patt = patt_5A5;
300				else
301					patt = patt_A5A;
302				err = check_eraseblock(i, patt);
303				if (err) {
304					pr_info("verify failed for %s"
305					       " pattern\n",
306					       ((eb + erase_cycles) & 1) ?
307					       "0x55AA55..." : "0xAA55AA...");
308					goto out;
309				}
310
311				err = mtdtest_relax();
312				if (err)
313					goto out;
314			}
315		}
316
317		erase_cycles += 1;
318
319		if (erase_cycles % gran == 0) {
320			long ms;
321
322			stop_timing();
323			ms = ktime_ms_delta(finish, start);
324			pr_info("%08u erase cycles done, took %lu "
325			       "milliseconds (%lu seconds)\n",
326			       erase_cycles, ms, ms / 1000);
327			start_timing();
328		}
329
330		if (!infinite && --cycles_count == 0)
331			break;
332	}
333out:
334
335	pr_info("finished after %u erase cycles\n",
336	       erase_cycles);
337	kfree(bad_ebs);
338out_check_buf:
339	kfree(check_buf);
340out_patt_FF:
341	kfree(patt_FF);
342out_patt_A5A:
343	kfree(patt_A5A);
344out_patt_5A5:
345	kfree(patt_5A5);
346out_mtd:
347	put_mtd_device(mtd);
348	if (err)
349		pr_info("error %d occurred during torturing\n", err);
350	printk(KERN_INFO "=================================================\n");
351	return err;
352}
353module_init(tort_init);
354
355static void __exit tort_exit(void)
356{
357	return;
358}
359module_exit(tort_exit);
360
361static int countdiffs(unsigned char *buf, unsigned char *check_buf,
362		      unsigned offset, unsigned len, unsigned *bytesp,
363		      unsigned *bitsp);
364static void print_bufs(unsigned char *read, unsigned char *written, int start,
365		       int len);
366
367/*
368 * Report the detailed information about how the read EB differs from what was
369 * written.
370 */
371static void report_corrupt(unsigned char *read, unsigned char *written)
372{
373	int i;
374	int bytes, bits, pages, first;
375	int offset, len;
376	size_t check_len = mtd->erasesize;
377
378	if (pgcnt)
379		check_len = pgcnt * pgsize;
380
381	bytes = bits = pages = 0;
382	for (i = 0; i < check_len; i += pgsize)
383		if (countdiffs(written, read, i, pgsize, &bytes,
384			       &bits) >= 0)
385			pages++;
386
387	pr_info("verify fails on %d pages, %d bytes/%d bits\n",
388	       pages, bytes, bits);
389	pr_info("The following is a list of all differences between"
390	       " what was read from flash and what was expected\n");
391
392	for (i = 0; i < check_len; i += pgsize) {
393		cond_resched();
394		bytes = bits = 0;
395		first = countdiffs(written, read, i, pgsize, &bytes,
396				   &bits);
397		if (first < 0)
398			continue;
399
400		printk("-------------------------------------------------------"
401		       "----------------------------------\n");
402
403		pr_info("Page %zd has %d bytes/%d bits failing verify,"
404		       " starting at offset 0x%x\n",
405		       (mtd->erasesize - check_len + i) / pgsize,
406		       bytes, bits, first);
407
408		offset = first & ~0x7;
409		len = ((first + bytes) | 0x7) + 1 - offset;
410
411		print_bufs(read, written, offset, len);
412	}
413}
414
415static void print_bufs(unsigned char *read, unsigned char *written, int start,
416		       int len)
417{
418	int i = 0, j1, j2;
419	char *diff;
420
421	printk("Offset       Read                          Written\n");
422	while (i < len) {
423		printk("0x%08x: ", start + i);
424		diff = "   ";
425		for (j1 = 0; j1 < 8 && i + j1 < len; j1++) {
426			printk(" %02x", read[start + i + j1]);
427			if (read[start + i + j1] != written[start + i + j1])
428				diff = "***";
429		}
430
431		while (j1 < 8) {
432			printk(" ");
433			j1 += 1;
434		}
435
436		printk("  %s ", diff);
437
438		for (j2 = 0; j2 < 8 && i + j2 < len; j2++)
439			printk(" %02x", written[start + i + j2]);
440		printk("\n");
441		i += 8;
442	}
443}
444
445/*
446 * Count the number of differing bytes and bits and return the first differing
447 * offset.
448 */
449static int countdiffs(unsigned char *buf, unsigned char *check_buf,
450		      unsigned offset, unsigned len, unsigned *bytesp,
451		      unsigned *bitsp)
452{
453	unsigned i, bit;
454	int first = -1;
455
456	for (i = offset; i < offset + len; i++)
457		if (buf[i] != check_buf[i]) {
458			first = i;
459			break;
460		}
461
462	while (i < offset + len) {
463		if (buf[i] != check_buf[i]) {
464			(*bytesp)++;
465			bit = 1;
466			while (bit < 256) {
467				if ((buf[i] & bit) != (check_buf[i] & bit))
468					(*bitsp)++;
469				bit <<= 1;
470			}
471		}
472		i++;
473	}
474
475	return first;
476}
477
478MODULE_DESCRIPTION("Eraseblock torturing module");
479MODULE_AUTHOR("Artem Bityutskiy, Jarkko Lavinen, Adrian Hunter");
480MODULE_LICENSE("GPL");
481