MTD: tests: add mtd_readtest

A simple tests which reads whole MTD device one page at a time.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

drivers/mtd/tests/mtd_readtest.c

+/*
+ * Copyright (C) 2006-2008 Nokia Corporation
+ *
+ * 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.
+ *
+ * Check MTD device read.
+ *
+ * Author: Adrian Hunter <ext-adrian.hunter@nokia.com>
+ */
+
+#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_readtest: "
+
+static int dev;
+module_param(dev, int, S_IRUGO);
+MODULE_PARM_DESC(dev, "MTD device number to use");
+
+static struct mtd_info *mtd;
+static unsigned char *iobuf;
+static unsigned char *iobuf1;
+static unsigned char *bbt;
+
+static int pgsize;
+static int ebcnt;
+static int pgcnt;
+
+static int read_eraseblock_by_page(int ebnum)
+{
+	size_t read = 0;
+	int i, ret, err = 0;
+	loff_t addr = ebnum * mtd->erasesize;
+	void *buf = iobuf;
+	void *oobbuf = iobuf1;
+
+	for (i = 0; i < pgcnt; i++) {
+		memset(buf, 0 , pgcnt);
+		ret = mtd->read(mtd, addr, pgsize, &read, buf);
+		if (ret == -EUCLEAN)
+			ret = 0;
+		if (ret || read != pgsize) {
+			printk(PRINT_PREF "error: read failed at %#llx\n",
+			       (long long)addr);
+			if (!err)
+				err = ret;
+			if (!err)
+				err = -EINVAL;
+		}
+		if (mtd->oobsize) {
+			struct mtd_oob_ops ops;
+
+			ops.mode      = MTD_OOB_PLACE;
+			ops.len       = 0;
+			ops.retlen    = 0;
+			ops.ooblen    = mtd->oobsize;
+			ops.oobretlen = 0;
+			ops.ooboffs   = 0;
+			ops.datbuf    = 0;
+			ops.oobbuf    = oobbuf;
+			ret = mtd->read_oob(mtd, addr, &ops);
+			if (ret || ops.oobretlen != mtd->oobsize) {
+				printk(PRINT_PREF "error: read oob failed at "
+						  "%#llx\n", (long long)addr);
+				if (!err)
+					err = ret;
+				if (!err)
+					err = -EINVAL;
+			}
+			oobbuf += mtd->oobsize;
+		}
+		addr += pgsize;
+		buf += pgsize;
+	}
+
+	return err;
+}
+
+static void dump_eraseblock(int ebnum)
+{
+	int i, j, n;
+	char line[128];
+	int pg, oob;
+
+	printk(PRINT_PREF "dumping eraseblock %d\n", ebnum);
+	n = mtd->erasesize;
+	for (i = 0; i < n;) {
+		char *p = line;
+
+		p += sprintf(p, "%05x: ", i);
+		for (j = 0; j < 32 && i < n; j++, i++)
+			p += sprintf(p, "%02x", (unsigned int)iobuf[i]);
+		printk(KERN_CRIT "%s\n", line);
+		cond_resched();
+	}
+	if (!mtd->oobsize)
+		return;
+	printk(PRINT_PREF "dumping oob from eraseblock %d\n", ebnum);
+	n = mtd->oobsize;
+	for (pg = 0, i = 0; pg < pgcnt; pg++)
+		for (oob = 0; oob < n;) {
+			char *p = line;
+
+			p += sprintf(p, "%05x: ", i);
+			for (j = 0; j < 32 && oob < n; j++, oob++, i++)
+				p += sprintf(p, "%02x",
+					     (unsigned int)iobuf1[i]);
+			printk(KERN_CRIT "%s\n", line);
+			cond_resched();
+		}
+}
+
+static int is_block_bad(int ebnum)
+{
+	loff_t addr = ebnum * mtd->erasesize;
+	int ret;
+
+	ret = mtd->block_isbad(mtd, addr);
+	if (ret)
+		printk(PRINT_PREF "block %d is bad\n", ebnum);
+	return ret;
+}
+
+static int scan_for_bad_eraseblocks(void)
+{
+	int i, bad = 0;
+
+	bbt = kmalloc(ebcnt, GFP_KERNEL);
+	if (!bbt) {
+		printk(PRINT_PREF "error: cannot allocate memory\n");
+		return -ENOMEM;
+	}
+	memset(bbt, 0 , ebcnt);
+
+	printk(PRINT_PREF "scanning for bad eraseblocks\n");
+	for (i = 0; i < ebcnt; ++i) {
+		bbt[i] = is_block_bad(i) ? 1 : 0;
+		if (bbt[i])
+			bad += 1;
+		cond_resched();
+	}
+	printk(PRINT_PREF "scanned %d eraseblocks, %d are bad\n", i, bad);
+	return 0;
+}
+
+static int __init mtd_readtest_init(void)
+{
+	uint64_t tmp;
+	int err, i;
+
+	printk(KERN_INFO "\n");
+	printk(KERN_INFO "=================================================\n");
+	printk(PRINT_PREF "MTD device: %d\n", dev);
+
+	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;
+
+	tmp = mtd->size;
+	do_div(tmp, mtd->erasesize);
+	ebcnt = tmp;
+	pgcnt = mtd->erasesize / mtd->writesize;
+
+	printk(PRINT_PREF "MTD device size %llu, eraseblock size %u, "
+	       "page size %u, count of eraseblocks %u, pages per "
+	       "eraseblock %u, OOB size %u\n",
+	       (unsigned long long)mtd->size, mtd->erasesize,
+	       pgsize, ebcnt, pgcnt, mtd->oobsize);
+
+	err = -ENOMEM;
+	iobuf = kmalloc(mtd->erasesize, GFP_KERNEL);
+	if (!iobuf) {
+		printk(PRINT_PREF "error: cannot allocate memory\n");
+		goto out;
+	}
+	iobuf1 = kmalloc(mtd->erasesize, GFP_KERNEL);
+	if (!iobuf1) {
+		printk(PRINT_PREF "error: cannot allocate memory\n");
+		goto out;
+	}
+
+	err = scan_for_bad_eraseblocks();
+	if (err)
+		goto out;
+
+	/* Read all eraseblocks 1 page at a time */
+	printk(PRINT_PREF "testing page read\n");
+	for (i = 0; i < ebcnt; ++i) {
+		int ret;
+
+		if (bbt[i])
+			continue;
+		ret = read_eraseblock_by_page(i);
+		if (ret) {
+			dump_eraseblock(i);
+			if (!err)
+				err = ret;
+		}
+		cond_resched();
+	}
+
+	if (err)
+		printk(PRINT_PREF "finished with errors\n");
+	else
+		printk(PRINT_PREF "finished\n");
+
+out:
+
+	kfree(iobuf);
+	kfree(iobuf1);
+	kfree(bbt);
+	put_mtd_device(mtd);
+	if (err)
+		printk(PRINT_PREF "error %d occurred\n", err);
+	printk(KERN_INFO "=================================================\n");
+	return err;
+}
+module_init(mtd_readtest_init);
+
+static void __exit mtd_readtest_exit(void)
+{
+	return;
+}
+module_exit(mtd_readtest_exit);
+
+MODULE_DESCRIPTION("Read test module");
+MODULE_AUTHOR("Adrian Hunter");
+MODULE_LICENSE("GPL");