drivers/mtd/tests/stresstest.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2006-2008 Nokia Corporation
   4  *
   5  * Test random reads, writes and erases on MTD device.
   6  *
   7  * Author: Adrian Hunter <ext-adrian.hunter@nokia.com>
   8  */
   9
  10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  11
  12 #include <linux/init.h>
  13 #include <linux/module.h>
  14 #include <linux/moduleparam.h>
  15 #include <linux/err.h>
  16 #include <linux/mtd/mtd.h>
  17 #include <linux/slab.h>
  18 #include <linux/sched.h>
  19 #include <linux/vmalloc.h>
  20 #include <linux/random.h>
  21
  22 #include "mtd_test.h"
  23
  24 static int dev = -EINVAL;
  25 module_param(dev, int, S_IRUGO);
  26 MODULE_PARM_DESC(dev, "MTD device number to use");
  27
  28 static int count = 10000;
  29 module_param(count, int, S_IRUGO);
  30 MODULE_PARM_DESC(count, "Number of operations to do (default is 10000)");
  31
  32 static struct mtd_info *mtd;
  33 static unsigned char *writebuf;
  34 static unsigned char *readbuf;
  35 static unsigned char *bbt;
  36 static int *offsets;
  37
  38 static int pgsize;
  39 static int bufsize;
  40 static int ebcnt;
  41 static int pgcnt;
  42
  43 static int rand_eb(void)
  44 {
  45         unsigned int eb;
  46
  47 again:
  48         eb = prandom_u32();
  49         /* Read or write up 2 eraseblocks at a time - hence 'ebcnt - 1' */
  50         eb %= (ebcnt - 1);
  51         if (bbt[eb])
  52                 goto again;
  53         return eb;
  54 }
  55
  56 static int rand_offs(void)
  57 {
  58         unsigned int offs;
  59
  60         offs = prandom_u32();
  61         offs %= bufsize;
  62         return offs;
  63 }
  64
  65 static int rand_len(int offs)
  66 {
  67         unsigned int len;
  68
  69         len = prandom_u32();
  70         len %= (bufsize - offs);
  71         return len;
  72 }
  73
  74 static int do_read(void)
  75 {
  76         int eb = rand_eb();
  77         int offs = rand_offs();
  78         int len = rand_len(offs);
  79         loff_t addr;
  80
  81         if (bbt[eb + 1]) {
  82                 if (offs >= mtd->erasesize)
  83                         offs -= mtd->erasesize;
  84                 if (offs + len > mtd->erasesize)
  85                         len = mtd->erasesize - offs;
  86         }
  87         addr = (loff_t)eb * mtd->erasesize + offs;
  88         return mtdtest_read(mtd, addr, len, readbuf);
  89 }
  90
  91 static int do_write(void)
  92 {
  93         int eb = rand_eb(), offs, err, len;
  94         loff_t addr;
  95
  96         offs = offsets[eb];
  97         if (offs >= mtd->erasesize) {
  98                 err = mtdtest_erase_eraseblock(mtd, eb);
  99                 if (err)
 100                         return err;
 101                 offs = offsets[eb] = 0;
 102         }
 103         len = rand_len(offs);
 104         len = ((len + pgsize - 1) / pgsize) * pgsize;
 105         if (offs + len > mtd->erasesize) {
 106                 if (bbt[eb + 1])
 107                         len = mtd->erasesize - offs;
 108                 else {
 109                         err = mtdtest_erase_eraseblock(mtd, eb + 1);
 110                         if (err)
 111                                 return err;
 112                         offsets[eb + 1] = 0;
 113                 }
 114         }
 115         addr = (loff_t)eb * mtd->erasesize + offs;
 116         err = mtdtest_write(mtd, addr, len, writebuf);
 117         if (unlikely(err))
 118                 return err;
 119         offs += len;
 120         while (offs > mtd->erasesize) {
 121                 offsets[eb++] = mtd->erasesize;
 122                 offs -= mtd->erasesize;
 123         }
 124         offsets[eb] = offs;
 125         return 0;
 126 }
 127
 128 static int do_operation(void)
 129 {
 130         if (prandom_u32() & 1)
 131                 return do_read();
 132         else
 133                 return do_write();
 134 }
 135
 136 static int __init mtd_stresstest_init(void)
 137 {
 138         int err;
 139         int i, op;
 140         uint64_t tmp;
 141
 142         printk(KERN_INFO "\n");
 143         printk(KERN_INFO "=================================================\n");
 144
 145         if (dev < 0) {
 146                 pr_info("Please specify a valid mtd-device via module parameter\n");
 147                 pr_crit("CAREFUL: This test wipes all data on the specified MTD device!\n");
 148                 return -EINVAL;
 149         }
 150
 151         pr_info("MTD device: %d\n", dev);
 152
 153         mtd = get_mtd_device(NULL, dev);
 154         if (IS_ERR(mtd)) {
 155                 err = PTR_ERR(mtd);
 156                 pr_err("error: cannot get MTD device\n");
 157                 return err;
 158         }
 159
 160         if (mtd->writesize == 1) {
 161                 pr_info("not NAND flash, assume page size is 512 "
 162                        "bytes.\n");
 163                 pgsize = 512;
 164         } else
 165                 pgsize = mtd->writesize;
 166
 167         tmp = mtd->size;
 168         do_div(tmp, mtd->erasesize);
 169         ebcnt = tmp;
 170         pgcnt = mtd->erasesize / pgsize;
 171
 172         pr_info("MTD device size %llu, eraseblock size %u, "
 173                "page size %u, count of eraseblocks %u, pages per "
 174                "eraseblock %u, OOB size %u\n",
 175                (unsigned long long)mtd->size, mtd->erasesize,
 176                pgsize, ebcnt, pgcnt, mtd->oobsize);
 177
 178         if (ebcnt < 2) {
 179                 pr_err("error: need at least 2 eraseblocks\n");
 180                 err = -ENOSPC;
 181                 goto out_put_mtd;
 182         }
 183
 184         /* Read or write up 2 eraseblocks at a time */
 185         bufsize = mtd->erasesize * 2;
 186
 187         err = -ENOMEM;
 188         readbuf = vmalloc(bufsize);
 189         writebuf = vmalloc(bufsize);
 190         offsets = kmalloc_array(ebcnt, sizeof(int), GFP_KERNEL);
 191         if (!readbuf || !writebuf || !offsets)
 192                 goto out;
 193         for (i = 0; i < ebcnt; i++)
 194                 offsets[i] = mtd->erasesize;
 195         prandom_bytes(writebuf, bufsize);
 196
 197         bbt = kzalloc(ebcnt, GFP_KERNEL);
 198         if (!bbt)
 199                 goto out;
 200         err = mtdtest_scan_for_bad_eraseblocks(mtd, bbt, 0, ebcnt);
 201         if (err)
 202                 goto out;
 203
 204         /* Do operations */
 205         pr_info("doing operations\n");
 206         for (op = 0; op < count; op++) {
 207                 if ((op & 1023) == 0)
 208                         pr_info("%d operations done\n", op);
 209                 err = do_operation();
 210                 if (err)
 211                         goto out;
 212
 213                 err = mtdtest_relax();
 214                 if (err)
 215                         goto out;
 216         }
 217         pr_info("finished, %d operations done\n", op);
 218
 219 out:
 220         kfree(offsets);
 221         kfree(bbt);
 222         vfree(writebuf);
 223         vfree(readbuf);
 224 out_put_mtd:
 225         put_mtd_device(mtd);
 226         if (err)
 227                 pr_info("error %d occurred\n", err);
 228         printk(KERN_INFO "=================================================\n");
 229         return err;
 230 }
 231 module_init(mtd_stresstest_init);
 232
 233 static void __exit mtd_stresstest_exit(void)
 234 {
 235         return;
 236 }
 237 module_exit(mtd_stresstest_exit);
 238
 239 MODULE_DESCRIPTION("Stress test module");
 240 MODULE_AUTHOR("Adrian Hunter");
 241 MODULE_LICENSE("GPL");