xref: /linux/drivers/mtd/tests/stresstest.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
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");
254