drivers/mtd/tests/mtd_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 static int dev = -EINVAL;
  35 module_param(dev, int, S_IRUGO);
  36 MODULE_PARM_DESC(dev, "MTD device number to use");
  37
  38 static int count = 10000;
  39 module_param(count, int, S_IRUGO);
  40 MODULE_PARM_DESC(count, "Number of operations to do (default is 10000)");
  41
  42 static struct mtd_info *mtd;
  43 static unsigned char *writebuf;
  44 static unsigned char *readbuf;
  45 static unsigned char *bbt;
  46 static int *offsets;
  47
  48 static int pgsize;
  49 static int bufsize;
  50 static int ebcnt;
  51 static int pgcnt;
  52
  53 static int rand_eb(void)
  54 {
  55         unsigned int eb;
  56
  57 again:
  58         eb = random32();
  59         /* Read or write up 2 eraseblocks at a time - hence 'ebcnt - 1' */
  60         eb %= (ebcnt - 1);
  61         if (bbt[eb])
  62                 goto again;
  63         return eb;
  64 }
  65
  66 static int rand_offs(void)
  67 {
  68         unsigned int offs;
  69
  70         offs = random32();
  71         offs %= bufsize;
  72         return offs;
  73 }
  74
  75 static int rand_len(int offs)
  76 {
  77         unsigned int len;
  78
  79         len = random32();
  80         len %= (bufsize - offs);
  81         return len;
  82 }
  83
  84 static int erase_eraseblock(int ebnum)
  85 {
  86         int err;
  87         struct erase_info ei;
  88         loff_t addr = ebnum * mtd->erasesize;
  89
  90         memset(&ei, 0, sizeof(struct erase_info));
  91         ei.mtd  = mtd;
  92         ei.addr = addr;
  93         ei.len  = mtd->erasesize;
  94
  95         err = mtd_erase(mtd, &ei);
  96         if (unlikely(err)) {
  97                 pr_err("error %d while erasing EB %d\n", err, ebnum);
  98                 return err;
  99         }
 100
 101         if (unlikely(ei.state == MTD_ERASE_FAILED)) {
 102                 pr_err("some erase error occurred at EB %d\n",
 103                        ebnum);
 104                 return -EIO;
 105         }
 106
 107         return 0;
 108 }
 109
 110 static int is_block_bad(int ebnum)
 111 {
 112         loff_t addr = ebnum * mtd->erasesize;
 113         int ret;
 114
 115         ret = mtd_block_isbad(mtd, addr);
 116         if (ret)
 117                 pr_info("block %d is bad\n", ebnum);
 118         return ret;
 119 }
 120
 121 static int do_read(void)
 122 {
 123         size_t read;
 124         int eb = rand_eb();
 125         int offs = rand_offs();
 126         int len = rand_len(offs), err;
 127         loff_t addr;
 128
 129         if (bbt[eb + 1]) {
 130                 if (offs >= mtd->erasesize)
 131                         offs -= mtd->erasesize;
 132                 if (offs + len > mtd->erasesize)
 133                         len = mtd->erasesize - offs;
 134         }
 135         addr = eb * mtd->erasesize + offs;
 136         err = mtd_read(mtd, addr, len, &read, readbuf);
 137         if (mtd_is_bitflip(err))
 138                 err = 0;
 139         if (unlikely(err || read != len)) {
 140                 pr_err("error: read failed at 0x%llx\n",
 141                        (long long)addr);
 142                 if (!err)
 143                         err = -EINVAL;
 144                 return err;
 145         }
 146         return 0;
 147 }
 148
 149 static int do_write(void)
 150 {
 151         int eb = rand_eb(), offs, err, len;
 152         size_t written;
 153         loff_t addr;
 154
 155         offs = offsets[eb];
 156         if (offs >= mtd->erasesize) {
 157                 err = erase_eraseblock(eb);
 158                 if (err)
 159                         return err;
 160                 offs = offsets[eb] = 0;
 161         }
 162         len = rand_len(offs);
 163         len = ((len + pgsize - 1) / pgsize) * pgsize;
 164         if (offs + len > mtd->erasesize) {
 165                 if (bbt[eb + 1])
 166                         len = mtd->erasesize - offs;
 167                 else {
 168                         err = erase_eraseblock(eb + 1);
 169                         if (err)
 170                                 return err;
 171                         offsets[eb + 1] = 0;
 172                 }
 173         }
 174         addr = eb * mtd->erasesize + offs;
 175         err = mtd_write(mtd, addr, len, &written, writebuf);
 176         if (unlikely(err || written != len)) {
 177                 pr_err("error: write failed at 0x%llx\n",
 178                        (long long)addr);
 179                 if (!err)
 180                         err = -EINVAL;
 181                 return err;
 182         }
 183         offs += len;
 184         while (offs > mtd->erasesize) {
 185                 offsets[eb++] = mtd->erasesize;
 186                 offs -= mtd->erasesize;
 187         }
 188         offsets[eb] = offs;
 189         return 0;
 190 }
 191
 192 static int do_operation(void)
 193 {
 194         if (random32() & 1)
 195                 return do_read();
 196         else
 197                 return do_write();
 198 }
 199
 200 static int scan_for_bad_eraseblocks(void)
 201 {
 202         int i, bad = 0;
 203
 204         bbt = kzalloc(ebcnt, GFP_KERNEL);
 205         if (!bbt) {
 206                 pr_err("error: cannot allocate memory\n");
 207                 return -ENOMEM;
 208         }
 209
 210         if (!mtd_can_have_bb(mtd))
 211                 return 0;
 212
 213         pr_info("scanning for bad eraseblocks\n");
 214         for (i = 0; i < ebcnt; ++i) {
 215                 bbt[i] = is_block_bad(i) ? 1 : 0;
 216                 if (bbt[i])
 217                         bad += 1;
 218                 cond_resched();
 219         }
 220         pr_info("scanned %d eraseblocks, %d are bad\n", i, bad);
 221         return 0;
 222 }
 223
 224 static int __init mtd_stresstest_init(void)
 225 {
 226         int err;
 227         int i, op;
 228         uint64_t tmp;
 229
 230         printk(KERN_INFO "\n");
 231         printk(KERN_INFO "=================================================\n");
 232
 233         if (dev < 0) {
 234                 pr_info("Please specify a valid mtd-device via module parameter\n");
 235                 pr_crit("CAREFUL: This test wipes all data on the specified MTD device!\n");
 236                 return -EINVAL;
 237         }
 238
 239         pr_info("MTD device: %d\n", dev);
 240
 241         mtd = get_mtd_device(NULL, dev);
 242         if (IS_ERR(mtd)) {
 243                 err = PTR_ERR(mtd);
 244                 pr_err("error: cannot get MTD device\n");
 245                 return err;
 246         }
 247
 248         if (mtd->writesize == 1) {
 249                 pr_info("not NAND flash, assume page size is 512 "
 250                        "bytes.\n");
 251                 pgsize = 512;
 252         } else
 253                 pgsize = mtd->writesize;
 254
 255         tmp = mtd->size;
 256         do_div(tmp, mtd->erasesize);
 257         ebcnt = tmp;
 258         pgcnt = mtd->erasesize / pgsize;
 259
 260         pr_info("MTD device size %llu, eraseblock size %u, "
 261                "page size %u, count of eraseblocks %u, pages per "
 262                "eraseblock %u, OOB size %u\n",
 263                (unsigned long long)mtd->size, mtd->erasesize,
 264                pgsize, ebcnt, pgcnt, mtd->oobsize);
 265
 266         if (ebcnt < 2) {
 267                 pr_err("error: need at least 2 eraseblocks\n");
 268                 err = -ENOSPC;
 269                 goto out_put_mtd;
 270         }
 271
 272         /* Read or write up 2 eraseblocks at a time */
 273         bufsize = mtd->erasesize * 2;
 274
 275         err = -ENOMEM;
 276         readbuf = vmalloc(bufsize);
 277         writebuf = vmalloc(bufsize);
 278         offsets = kmalloc(ebcnt * sizeof(int), GFP_KERNEL);
 279         if (!readbuf || !writebuf || !offsets) {
 280                 pr_err("error: cannot allocate memory\n");
 281                 goto out;
 282         }
 283         for (i = 0; i < ebcnt; i++)
 284                 offsets[i] = mtd->erasesize;
 285         for (i = 0; i < bufsize; i++)
 286                 writebuf[i] = random32();
 287
 288         err = scan_for_bad_eraseblocks();
 289         if (err)
 290                 goto out;
 291
 292         /* Do operations */
 293         pr_info("doing operations\n");
 294         for (op = 0; op < count; op++) {
 295                 if ((op & 1023) == 0)
 296                         pr_info("%d operations done\n", op);
 297                 err = do_operation();
 298                 if (err)
 299                         goto out;
 300                 cond_resched();
 301         }
 302         pr_info("finished, %d operations done\n", op);
 303
 304 out:
 305         kfree(offsets);
 306         kfree(bbt);
 307         vfree(writebuf);
 308         vfree(readbuf);
 309 out_put_mtd:
 310         put_mtd_device(mtd);
 311         if (err)
 312                 pr_info("error %d occurred\n", err);
 313         printk(KERN_INFO "=================================================\n");
 314         return err;
 315 }
 316 module_init(mtd_stresstest_init);
 317
 318 static void __exit mtd_stresstest_exit(void)
 319 {
 320         return;
 321 }
 322 module_exit(mtd_stresstest_exit);
 323
 324 MODULE_DESCRIPTION("Stress test module");
 325 MODULE_AUTHOR("Adrian Hunter");
 326 MODULE_LICENSE("GPL");