MTD: tests: add mtd_torturetest

This test is designed to work for very long time and it tries to
wear few eraseblocks.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

drivers/mtd/tests/mtd_torturetest.c

+/*
+ * Copyright (C) 2006-2008 Artem Bityutskiy
+ * Copyright (C) 2006-2008 Jarkko Lavinen
+ * Copyright (C) 2006-2008 Adrian Hunter
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; see the file COPYING. If not, write to the Free Software
+ * Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Authors: Artem Bityutskiy, Jarkko Lavinen, Adria Hunter
+ *
+ * WARNING: this test program may kill your flash and your device. Do not
+ * use it unless you know what you do. Authors are not responsible for any
+ * damage caused by this program.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/err.h>
+#include <linux/mtd/mtd.h>
+#include <linux/sched.h>
+
+#define PRINT_PREF KERN_INFO "mtd_torturetest: "
+#define RETRIES 3
+
+static int eb = 8;
+module_param(eb, int, S_IRUGO);
+MODULE_PARM_DESC(eb, "eraseblock number within the selected MTD device");
+
+static int ebcnt = 32;
+module_param(ebcnt, int, S_IRUGO);
+MODULE_PARM_DESC(ebcnt, "number of consecutive eraseblocks to torture");
+
+static int pgcnt;
+module_param(pgcnt, int, S_IRUGO);
+MODULE_PARM_DESC(pgcnt, "number of pages per eraseblock to torture (0 => all)");
+
+static int dev;
+module_param(dev, int, S_IRUGO);
+MODULE_PARM_DESC(dev, "MTD device number to use");
+
+static int gran = 512;
+module_param(gran, int, S_IRUGO);
+MODULE_PARM_DESC(gran, "how often the status information should be printed");
+
+static int check = 1;
+module_param(check, int, S_IRUGO);
+MODULE_PARM_DESC(check, "if the written data should be checked");
+
+static unsigned int cycles_count;
+module_param(cycles_count, uint, S_IRUGO);
+MODULE_PARM_DESC(cycles_count, "how many erase cycles to do "
+			       "(infinite by default)");
+
+static struct mtd_info *mtd;
+
+/* This buffer contains 0x555555...0xAAAAAA... pattern */
+static unsigned char *patt_5A5;
+/* This buffer contains 0xAAAAAA...0x555555... pattern */
+static unsigned char *patt_A5A;
+/* This buffer contains all 0xFF bytes */
+static unsigned char *patt_FF;
+/* This a temporary buffer is use when checking data */
+static unsigned char *check_buf;
+/* How many erase cycles were done */
+static unsigned int erase_cycles;
+
+static int pgsize;
+static struct timeval start, finish;
+
+static void report_corrupt(unsigned char *read, unsigned char *written);
+
+static inline void start_timing(void)
+{
+	do_gettimeofday(&start);
+}
+
+static inline void stop_timing(void)
+{
+	do_gettimeofday(&finish);
+}
+
+/*
+ * Erase eraseblock number @ebnum.
+ */
+static inline int erase_eraseblock(int ebnum)
+{
+	int err;
+	struct erase_info ei;
+	loff_t addr = ebnum * mtd->erasesize;
+
+	memset(&ei, 0, sizeof(struct erase_info));
+	ei.mtd  = mtd;
+	ei.addr = addr;
+	ei.len  = mtd->erasesize;
+
+	err = mtd->erase(mtd, &ei);
+	if (err) {
+		printk(PRINT_PREF "error %d while erasing EB %d\n", err, ebnum);
+		return err;
+	}
+
+	if (ei.state == MTD_ERASE_FAILED) {
+		printk(PRINT_PREF "some erase error occurred at EB %d\n",
+		       ebnum);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+/*
+ * Check that the contents of eraseblock number @enbum is equivalent to the
+ * @buf buffer.
+ */
+static inline int check_eraseblock(int ebnum, unsigned char *buf)
+{
+	int err, retries = 0;
+	size_t read = 0;
+	loff_t addr = ebnum * mtd->erasesize;
+	size_t len = mtd->erasesize;
+
+	if (pgcnt) {
+		addr = (ebnum + 1) * mtd->erasesize - pgcnt * pgsize;
+		len = pgcnt * pgsize;
+	}
+
+retry:
+	err = mtd->read(mtd, addr, len, &read, check_buf);
+	if (err == -EUCLEAN)
+		printk(PRINT_PREF "single bit flip occurred at EB %d "
+		       "MTD reported that it was fixed.\n", ebnum);
+	else if (err) {
+		printk(PRINT_PREF "error %d while reading EB %d, "
+		       "read %zd\n", err, ebnum, read);
+		return err;
+	}
+
+	if (read != len) {
+		printk(PRINT_PREF "failed to read %zd bytes from EB %d, "
+		       "read only %zd, but no error reported\n",
+		       len, ebnum, read);
+		return -EIO;
+	}
+
+	if (memcmp(buf, check_buf, len)) {
+		printk(PRINT_PREF "read wrong data from EB %d\n", ebnum);
+		report_corrupt(check_buf, buf);
+
+		if (retries++ < RETRIES) {
+			/* Try read again */
+			yield();
+			printk(PRINT_PREF "re-try reading data from EB %d\n",
+			       ebnum);
+			goto retry;
+		} else {
+			printk(PRINT_PREF "retried %d times, still errors, "
+			       "give-up\n", RETRIES);
+			return -EINVAL;
+		}
+	}
+
+	if (retries != 0)
+		printk(PRINT_PREF "only attempt number %d was OK (!!!)\n",
+		       retries);
+
+	return 0;
+}
+
+static inline int write_pattern(int ebnum, void *buf)
+{
+	int err;
+	size_t written = 0;
+	loff_t addr = ebnum * mtd->erasesize;
+	size_t len = mtd->erasesize;
+
+	if (pgcnt) {
+		addr = (ebnum + 1) * mtd->erasesize - pgcnt * pgsize;
+		len = pgcnt * pgsize;
+	}
+	err = mtd->write(mtd, addr, len, &written, buf);
+	if (err) {
+		printk(PRINT_PREF "error %d while writing EB %d, written %zd"
+		      " bytes\n", err, ebnum, written);
+		return err;
+	}
+	if (written != len) {
+		printk(PRINT_PREF "written only %zd bytes of %zd, but no error"
+		       " reported\n", written, len);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static int __init tort_init(void)
+{
+	int err = 0, i, infinite = !cycles_count;
+	int bad_ebs[ebcnt];
+
+	printk(KERN_INFO "\n");
+	printk(KERN_INFO "=================================================\n");
+	printk(PRINT_PREF "Warning: this program is trying to wear out your "
+	       "flash, stop it if this is not wanted.\n");
+	printk(PRINT_PREF "MTD device: %d\n", dev);
+	printk(PRINT_PREF "torture %d eraseblocks (%d-%d) of mtd%d\n",
+	       ebcnt, eb, eb + ebcnt - 1, dev);
+	if (pgcnt)
+		printk(PRINT_PREF "torturing just %d pages per eraseblock\n",
+			pgcnt);
+	printk(PRINT_PREF "write verify %s\n", check ? "enabled" : "disabled");
+
+	mtd = get_mtd_device(NULL, dev);
+	if (IS_ERR(mtd)) {
+		err = PTR_ERR(mtd);
+		printk(PRINT_PREF "error: cannot get MTD device\n");
+		return err;
+	}
+
+	if (mtd->writesize == 1) {
+		printk(PRINT_PREF "not NAND flash, assume page size is 512 "
+		       "bytes.\n");
+		pgsize = 512;
+	} else
+		pgsize = mtd->writesize;
+
+	if (pgcnt && (pgcnt > mtd->erasesize / pgsize || pgcnt < 0)) {
+		printk(PRINT_PREF "error: invalid pgcnt value %d\n", pgcnt);
+		goto out_mtd;
+	}
+
+	err = -ENOMEM;
+	patt_5A5 = kmalloc(mtd->erasesize, GFP_KERNEL);
+	if (!patt_5A5) {
+		printk(PRINT_PREF "error: cannot allocate memory\n");
+		goto out_mtd;
+	}
+
+	patt_A5A = kmalloc(mtd->erasesize, GFP_KERNEL);
+	if (!patt_A5A) {
+		printk(PRINT_PREF "error: cannot allocate memory\n");
+		goto out_patt_5A5;
+	}
+
+	patt_FF = kmalloc(mtd->erasesize, GFP_KERNEL);
+	if (!patt_FF) {
+		printk(PRINT_PREF "error: cannot allocate memory\n");
+		goto out_patt_A5A;
+	}
+
+	check_buf = kmalloc(mtd->erasesize, GFP_KERNEL);
+	if (!check_buf) {
+		printk(PRINT_PREF "error: cannot allocate memory\n");
+		goto out_patt_FF;
+	}
+
+	err = 0;
+
+	/* Initialize patterns */
+	memset(patt_FF, 0xFF, mtd->erasesize);
+	for (i = 0; i < mtd->erasesize / pgsize; i++) {
+		if (!(i & 1)) {
+			memset(patt_5A5 + i * pgsize, 0x55, pgsize);
+			memset(patt_A5A + i * pgsize, 0xAA, pgsize);
+		} else {
+			memset(patt_5A5 + i * pgsize, 0xAA, pgsize);
+			memset(patt_A5A + i * pgsize, 0x55, pgsize);
+		}
+	}
+
+	/*
+	 * Check if there is a bad eraseblock among those we are going to test.
+	 */
+	memset(&bad_ebs[0], 0, sizeof(int) * ebcnt);
+	if (mtd->block_isbad) {
+		for (i = eb; i < eb + ebcnt; i++) {
+			err = mtd->block_isbad(mtd,
+					       (loff_t)i * mtd->erasesize);
+
+			if (err < 0) {
+				printk(PRINT_PREF "block_isbad() returned %d "
+				       "for EB %d\n", err, i);
+				goto out;
+			}
+
+			if (err) {
+				printk("EB %d is bad. Skip it.\n", i);
+				bad_ebs[i - eb] = 1;
+			}
+		}
+	}
+
+	start_timing();
+	while (1) {
+		int i;
+		void *patt;
+
+		/* Erase all eraseblocks */
+		for (i = eb; i < eb + ebcnt; i++) {
+			if (bad_ebs[i - eb])
+				continue;
+			err = erase_eraseblock(i);
+			if (err)
+				goto out;
+			cond_resched();
+		}
+
+		/* Check if the eraseblocks contain only 0xFF bytes */
+		if (check) {
+			for (i = eb; i < eb + ebcnt; i++) {
+				if (bad_ebs[i - eb])
+					continue;
+				err = check_eraseblock(i, patt_FF);
+				if (err) {
+					printk(PRINT_PREF "verify failed"
+					       " for 0xFF... pattern\n");
+					goto out;
+				}
+				cond_resched();
+			}
+		}
+
+		/* Write the pattern */
+		for (i = eb; i < eb + ebcnt; i++) {
+			if (bad_ebs[i - eb])
+				continue;
+			if ((eb + erase_cycles) & 1)
+				patt = patt_5A5;
+			else
+				patt = patt_A5A;
+			err = write_pattern(i, patt);
+			if (err)
+				goto out;
+			cond_resched();
+		}
+
+		/* Verify what we wrote */
+		if (check) {
+			for (i = eb; i < eb + ebcnt; i++) {
+				if (bad_ebs[i - eb])
+					continue;
+				if ((eb + erase_cycles) & 1)
+					patt = patt_5A5;
+				else
+					patt = patt_A5A;
+				err = check_eraseblock(i, patt);
+				if (err) {
+					printk(PRINT_PREF "verify failed for %s"
+					       " pattern\n",
+					       ((eb + erase_cycles) & 1) ?
+					       "0x55AA55..." : "0xAA55AA...");
+					goto out;
+				}
+				cond_resched();
+			}
+		}
+
+		erase_cycles += 1;
+
+		if (erase_cycles % gran == 0) {
+			long ms;
+
+			stop_timing();
+			ms = (finish.tv_sec - start.tv_sec) * 1000 +
+			     (finish.tv_usec - start.tv_usec) / 1000;
+			printk(PRINT_PREF "%08u erase cycles done, took %lu "
+			       "milliseconds (%lu seconds)\n",
+			       erase_cycles, ms, ms / 1000);
+			start_timing();
+		}
+
+		if (!infinite && --cycles_count == 0)
+			break;
+	}
+out:
+
+	printk(PRINT_PREF "finished after %u erase cycles\n",
+	       erase_cycles);
+	kfree(check_buf);
+out_patt_FF:
+	kfree(patt_FF);
+out_patt_A5A:
+	kfree(patt_A5A);
+out_patt_5A5:
+	kfree(patt_5A5);
+out_mtd:
+	put_mtd_device(mtd);
+	if (err)
+		printk(PRINT_PREF "error %d occurred during torturing\n", err);
+	printk(KERN_INFO "=================================================\n");
+	return err;
+}
+module_init(tort_init);
+
+static void __exit tort_exit(void)
+{
+	return;
+}
+module_exit(tort_exit);
+
+static int countdiffs(unsigned char *buf, unsigned char *check_buf,
+		      unsigned offset, unsigned len, unsigned *bytesp,
+		      unsigned *bitsp);
+static void print_bufs(unsigned char *read, unsigned char *written, int start,
+		       int len);
+
+/*
+ * Report the detailed information about how the read EB differs from what was
+ * written.
+ */
+static void report_corrupt(unsigned char *read, unsigned char *written)
+{
+	int i;
+	int bytes, bits, pages, first;
+	int offset, len;
+	size_t check_len = mtd->erasesize;
+
+	if (pgcnt)
+		check_len = pgcnt * pgsize;
+
+	bytes = bits = pages = 0;
+	for (i = 0; i < check_len; i += pgsize)
+		if (countdiffs(written, read, i, pgsize, &bytes,
+			       &bits) >= 0)
+			pages++;
+
+	printk(PRINT_PREF "verify fails on %d pages, %d bytes/%d bits\n",
+	       pages, bytes, bits);
+	printk(PRINT_PREF "The following is a list of all differences between"
+	       " what was read from flash and what was expected\n");
+
+	for (i = 0; i < check_len; i += pgsize) {
+		cond_resched();
+		bytes = bits = 0;
+		first = countdiffs(written, read, i, pgsize, &bytes,
+				   &bits);
+		if (first < 0)
+			continue;
+
+		printk("-------------------------------------------------------"
+		       "----------------------------------\n");
+
+		printk(PRINT_PREF "Page %d has %d bytes/%d bits failing verify,"
+		       " starting at offset 0x%x\n",
+		       (mtd->erasesize - check_len + i) / pgsize,
+		       bytes, bits, first);
+
+		offset = first & ~0x7;
+		len = ((first + bytes) | 0x7) + 1 - offset;
+
+		print_bufs(read, written, offset, len);
+	}
+}
+
+static void print_bufs(unsigned char *read, unsigned char *written, int start,
+		       int len)
+{
+	int i = 0, j1, j2;
+	char *diff;
+
+	printk("Offset       Read                          Written\n");
+	while (i < len) {
+		printk("0x%08x: ", start + i);
+		diff = "   ";
+		for (j1 = 0; j1 < 8 && i + j1 < len; j1++) {
+			printk(" %02x", read[start + i + j1]);
+			if (read[start + i + j1] != written[start + i + j1])
+				diff = "***";
+		}
+
+		while (j1 < 8) {
+			printk(" ");
+			j1 += 1;
+		}
+
+		printk("  %s ", diff);
+
+		for (j2 = 0; j2 < 8 && i + j2 < len; j2++)
+			printk(" %02x", written[start + i + j2]);
+		printk("\n");
+		i += 8;
+	}
+}
+
+/*
+ * Count the number of differing bytes and bits and return the first differing
+ * offset.
+ */
+static int countdiffs(unsigned char *buf, unsigned char *check_buf,
+		      unsigned offset, unsigned len, unsigned *bytesp,
+		      unsigned *bitsp)
+{
+	unsigned i, bit;
+	int first = -1;
+
+	for (i = offset; i < offset + len; i++)
+		if (buf[i] != check_buf[i]) {
+			first = i;
+			break;
+		}
+
+	while (i < offset + len) {
+		if (buf[i] != check_buf[i]) {
+			(*bytesp)++;
+			bit = 1;
+			while (bit < 256) {
+				if ((buf[i] & bit) != (check_buf[i] & bit))
+					(*bitsp)++;
+				bit <<= 1;
+			}
+		}
+		i++;
+	}
+
+	return first;
+}
+
+MODULE_DESCRIPTION("Eraseblock torturing module");
+MODULE_AUTHOR("Artem Bityutskiy, Jarkko Lavinen, Adrian Hunter");
+MODULE_LICENSE("GPL");