drivers/mtd/tests/stresstest.c

   1 /*
   2  * Copyright (C) 2006-2008 Nokia Corporation
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU General Public License version 2 as published by
   6  * the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
  11  * more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with
  14  * this program; see the file COPYING. If not, write to the Free Software
  15  * Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  16  *
  17  * Test random reads, writes and erases on MTD device.
  18  *
  19  * Author: Adrian Hunter <ext-adrian.hunter@nokia.com>
  20  */
  21
  22 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  23
  24 #include <linux/init.h>
  25 #include <linux/module.h>
  26 #include <linux/moduleparam.h>
  27 #include <linux/err.h>
  28 #include <linux/mtd/mtd.h>
  29 #include <linux/slab.h>
  30 #include <linux/sched.h>
  31 #include <linux/vmalloc.h>
  32 #include <linux/random.h>
  33
  34 #include "mtd_test.h"
  35
  36 static int dev = -EINVAL;
  37 module_param(dev, int, S_IRUGO);
  38 MODULE_PARM_DESC(dev, "MTD device number to use");
  39
  40 static int count = 10000;
  41 module_param(count, int, S_IRUGO);
  42 MODULE_PARM_DESC(count, "Number of operations to do (default is 10000)");
  43
  44 static struct mtd_info *mtd;
  45 static unsigned char *writebuf;
  46 static unsigned char *readbuf;
  47 static unsigned char *bbt;
  48 static int *offsets;
  49
  50 static int pgsize;
  51 static int bufsize;
  52 static int ebcnt;
  53 static int pgcnt;
  54
  55 static int rand_eb(void)
  56 {
  57         unsigned int eb;
  58
  59 again:
  60         eb = prandom_u32();
  61         /* Read or write up 2 eraseblocks at a time - hence 'ebcnt - 1' */
  62         eb %= (ebcnt - 1);
  63         if (bbt[eb])
  64                 goto again;
  65         return eb;
  66 }
  67
  68 static int rand_offs(void)
  69 {
  70         unsigned int offs;
  71
  72         offs = prandom_u32();
  73         offs %= bufsize;
  74         return offs;
  75 }
  76
  77 static int rand_len(int offs)
  78 {
  79         unsigned int len;
  80
  81         len = prandom_u32();
  82         len %= (bufsize - offs);
  83         return len;
  84 }
  85
  86 static int do_read(void)
  87 {
  88         int eb = rand_eb();
  89         int offs = rand_offs();
  90         int len = rand_len(offs);
  91         loff_t addr;
  92
  93         if (bbt[eb + 1]) {
  94                 if (offs >= mtd->erasesize)
  95                         offs -= mtd->erasesize;
  96                 if (offs + len > mtd->erasesize)
  97                         len = mtd->erasesize - offs;
  98         }
  99         addr = (loff_t)eb * mtd->erasesize + offs;
 100         return mtdtest_read(mtd, addr, len, readbuf);
 101 }
 102
 103 static int do_write(void)
 104 {
 105         int eb = rand_eb(), offs, err, len;
 106         loff_t addr;
 107
 108         offs = offsets[eb];
 109         if (offs >= mtd->erasesize) {
 110                 err = mtdtest_erase_eraseblock(mtd, eb);
 111                 if (err)
 112                         return err;
 113                 offs = offsets[eb] = 0;
 114         }
 115         len = rand_len(offs);
 116         len = ((len + pgsize - 1) / pgsize) * pgsize;
 117         if (offs + len > mtd->erasesize) {
 118                 if (bbt[eb + 1])
 119                         len = mtd->erasesize - offs;
 120                 else {
 121                         err = mtdtest_erase_eraseblock(mtd, eb + 1);
 122                         if (err)
 123                                 return err;
 124                         offsets[eb + 1] = 0;
 125                 }
 126         }
 127         addr = (loff_t)eb * mtd->erasesize + offs;
 128         err = mtdtest_write(mtd, addr, len, writebuf);
 129         if (unlikely(err))
 130                 return err;
 131         offs += len;
 132         while (offs > mtd->erasesize) {
 133                 offsets[eb++] = mtd->erasesize;
 134                 offs -= mtd->erasesize;
 135         }
 136         offsets[eb] = offs;
 137         return 0;
 138 }
 139
 140 static int do_operation(void)
 141 {
 142         if (prandom_u32() & 1)
 143                 return do_read();
 144         else
 145                 return do_write();
 146 }
 147
 148 static int __init mtd_stresstest_init(void)
 149 {
 150         int err;
 151         int i, op;
 152         uint64_t tmp;
 153
 154         printk(KERN_INFO "\n");
 155         printk(KERN_INFO "=================================================\n");
 156
 157         if (dev < 0) {
 158                 pr_info("Please specify a valid mtd-device via module parameter\n");
 159                 pr_crit("CAREFUL: This test wipes all data on the specified MTD device!\n");
 160                 return -EINVAL;
 161         }
 162
 163         pr_info("MTD device: %d\n", dev);
 164
 165         mtd = get_mtd_device(NULL, dev);
 166         if (IS_ERR(mtd)) {
 167                 err = PTR_ERR(mtd);
 168                 pr_err("error: cannot get MTD device\n");
 169                 return err;
 170         }
 171
 172         if (mtd->writesize == 1) {
 173                 pr_info("not NAND flash, assume page size is 512 "
 174                        "bytes.\n");
 175                 pgsize = 512;
 176         } else
 177                 pgsize = mtd->writesize;
 178
 179         tmp = mtd->size;
 180         do_div(tmp, mtd->erasesize);
 181         ebcnt = tmp;
 182         pgcnt = mtd->erasesize / pgsize;
 183
 184         pr_info("MTD device size %llu, eraseblock size %u, "
 185                "page size %u, count of eraseblocks %u, pages per "
 186                "eraseblock %u, OOB size %u\n",
 187                (unsigned long long)mtd->size, mtd->erasesize,
 188                pgsize, ebcnt, pgcnt, mtd->oobsize);
 189
 190         if (ebcnt < 2) {
 191                 pr_err("error: need at least 2 eraseblocks\n");
 192                 err = -ENOSPC;
 193                 goto out_put_mtd;
 194         }
 195
 196         /* Read or write up 2 eraseblocks at a time */
 197         bufsize = mtd->erasesize * 2;
 198
 199         err = -ENOMEM;
 200         readbuf = vmalloc(bufsize);
 201         writebuf = vmalloc(bufsize);
 202         offsets = kmalloc(ebcnt * sizeof(int), GFP_KERNEL);
 203         if (!readbuf || !writebuf || !offsets)
 204                 goto out;
 205         for (i = 0; i < ebcnt; i++)
 206                 offsets[i] = mtd->erasesize;
 207         prandom_bytes(writebuf, bufsize);
 208
 209         bbt = kzalloc(ebcnt, GFP_KERNEL);
 210         if (!bbt)
 211                 goto out;
 212         err = mtdtest_scan_for_bad_eraseblocks(mtd, bbt, 0, ebcnt);
 213         if (err)
 214                 goto out;
 215
 216         /* Do operations */
 217         pr_info("doing operations\n");
 218         for (op = 0; op < count; op++) {
 219                 if ((op & 1023) == 0)
 220                         pr_info("%d operations done\n", op);
 221                 err = do_operation();
 222                 if (err)
 223                         goto out;
 224
 225                 err = mtdtest_relax();
 226                 if (err)
 227                         goto out;
 228         }
 229         pr_info("finished, %d operations done\n", op);
 230
 231 out:
 232         kfree(offsets);
 233         kfree(bbt);
 234         vfree(writebuf);
 235         vfree(readbuf);
 236 out_put_mtd:
 237         put_mtd_device(mtd);
 238         if (err)
 239                 pr_info("error %d occurred\n", err);
 240         printk(KERN_INFO "=================================================\n");
 241         return err;
 242 }
 243 module_init(mtd_stresstest_init);
 244
 245 static void __exit mtd_stresstest_exit(void)
 246 {
 247         return;
 248 }
 249 module_exit(mtd_stresstest_exit);
 250
 251 MODULE_DESCRIPTION("Stress test module");
 252 MODULE_AUTHOR("Adrian Hunter");
 253 MODULE_LICENSE("GPL");