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 = 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 = 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 cond_resched(); 225 } 226 pr_info("finished, %d operations done\n", op); 227 228 out: 229 kfree(offsets); 230 kfree(bbt); 231 vfree(writebuf); 232 vfree(readbuf); 233 out_put_mtd: 234 put_mtd_device(mtd); 235 if (err) 236 pr_info("error %d occurred\n", err); 237 printk(KERN_INFO "=================================================\n"); 238 return err; 239 } 240 module_init(mtd_stresstest_init); 241 242 static void __exit mtd_stresstest_exit(void) 243 { 244 return; 245 } 246 module_exit(mtd_stresstest_exit); 247 248 MODULE_DESCRIPTION("Stress test module"); 249 MODULE_AUTHOR("Adrian Hunter"); 250 MODULE_LICENSE("GPL"); 251