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
rand_eb(void)43 static int rand_eb(void)
44 {
45 unsigned int eb;
46
47 again:
48 /* Read or write up 2 eraseblocks at a time - hence 'ebcnt - 1' */
49 eb = get_random_u32_below(ebcnt - 1);
50 if (bbt[eb])
51 goto again;
52 return eb;
53 }
54
rand_offs(void)55 static int rand_offs(void)
56 {
57 return get_random_u32_below(bufsize);
58 }
59
rand_len(int offs)60 static int rand_len(int offs)
61 {
62 return get_random_u32_below(bufsize - offs);
63 }
64
do_read(void)65 static int do_read(void)
66 {
67 int eb = rand_eb();
68 int offs = rand_offs();
69 int len = rand_len(offs);
70 loff_t addr;
71
72 if (bbt[eb + 1]) {
73 if (offs >= mtd->erasesize)
74 offs -= mtd->erasesize;
75 if (offs + len > mtd->erasesize)
76 len = mtd->erasesize - offs;
77 }
78 addr = (loff_t)eb * mtd->erasesize + offs;
79 return mtdtest_read(mtd, addr, len, readbuf);
80 }
81
do_write(void)82 static int do_write(void)
83 {
84 int eb = rand_eb(), offs, err, len;
85 loff_t addr;
86
87 offs = offsets[eb];
88 if (offs >= mtd->erasesize) {
89 err = mtdtest_erase_eraseblock(mtd, eb);
90 if (err)
91 return err;
92 offs = offsets[eb] = 0;
93 }
94 len = rand_len(offs);
95 len = ((len + pgsize - 1) / pgsize) * pgsize;
96 if (offs + len > mtd->erasesize) {
97 if (bbt[eb + 1])
98 len = mtd->erasesize - offs;
99 else {
100 err = mtdtest_erase_eraseblock(mtd, eb + 1);
101 if (err)
102 return err;
103 offsets[eb + 1] = 0;
104 }
105 }
106 addr = (loff_t)eb * mtd->erasesize + offs;
107 err = mtdtest_write(mtd, addr, len, writebuf);
108 if (unlikely(err))
109 return err;
110 offs += len;
111 while (offs > mtd->erasesize) {
112 offsets[eb++] = mtd->erasesize;
113 offs -= mtd->erasesize;
114 }
115 offsets[eb] = offs;
116 return 0;
117 }
118
do_operation(void)119 static int do_operation(void)
120 {
121 if (get_random_u32_below(2))
122 return do_read();
123 else
124 return do_write();
125 }
126
mtd_stresstest_init(void)127 static int __init mtd_stresstest_init(void)
128 {
129 int err;
130 int i, op;
131 uint64_t tmp;
132
133 printk(KERN_INFO "\n");
134 printk(KERN_INFO "=================================================\n");
135
136 if (dev < 0) {
137 pr_info("Please specify a valid mtd-device via module parameter\n");
138 pr_crit("CAREFUL: This test wipes all data on the specified MTD device!\n");
139 return -EINVAL;
140 }
141
142 pr_info("MTD device: %d\n", dev);
143
144 mtd = get_mtd_device(NULL, dev);
145 if (IS_ERR(mtd)) {
146 err = PTR_ERR(mtd);
147 pr_err("error: cannot get MTD device\n");
148 return err;
149 }
150
151 if (mtd->writesize == 1) {
152 pr_info("not NAND flash, assume page size is 512 "
153 "bytes.\n");
154 pgsize = 512;
155 } else
156 pgsize = mtd->writesize;
157
158 tmp = mtd->size;
159 do_div(tmp, mtd->erasesize);
160 ebcnt = tmp;
161 pgcnt = mtd->erasesize / pgsize;
162
163 pr_info("MTD device size %llu, eraseblock size %u, "
164 "page size %u, count of eraseblocks %u, pages per "
165 "eraseblock %u, OOB size %u\n",
166 (unsigned long long)mtd->size, mtd->erasesize,
167 pgsize, ebcnt, pgcnt, mtd->oobsize);
168
169 if (ebcnt < 2) {
170 pr_err("error: need at least 2 eraseblocks\n");
171 err = -ENOSPC;
172 goto out_put_mtd;
173 }
174
175 /* Read or write up 2 eraseblocks at a time */
176 bufsize = mtd->erasesize * 2;
177
178 err = -ENOMEM;
179 readbuf = vmalloc(bufsize);
180 writebuf = vmalloc(bufsize);
181 offsets = kmalloc_array(ebcnt, sizeof(int), GFP_KERNEL);
182 if (!readbuf || !writebuf || !offsets)
183 goto out;
184 for (i = 0; i < ebcnt; i++)
185 offsets[i] = mtd->erasesize;
186 get_random_bytes(writebuf, bufsize);
187
188 bbt = kzalloc(ebcnt, GFP_KERNEL);
189 if (!bbt)
190 goto out;
191 err = mtdtest_scan_for_bad_eraseblocks(mtd, bbt, 0, ebcnt);
192 if (err)
193 goto out;
194
195 /* Do operations */
196 pr_info("doing operations\n");
197 for (op = 0; op < count; op++) {
198 if ((op & 1023) == 0)
199 pr_info("%d operations done\n", op);
200 err = do_operation();
201 if (err)
202 goto out;
203
204 err = mtdtest_relax();
205 if (err)
206 goto out;
207 }
208 pr_info("finished, %d operations done\n", op);
209
210 out:
211 kfree(offsets);
212 kfree(bbt);
213 vfree(writebuf);
214 vfree(readbuf);
215 out_put_mtd:
216 put_mtd_device(mtd);
217 if (err)
218 pr_info("error %d occurred\n", err);
219 printk(KERN_INFO "=================================================\n");
220 return err;
221 }
222 module_init(mtd_stresstest_init);
223
mtd_stresstest_exit(void)224 static void __exit mtd_stresstest_exit(void)
225 {
226 return;
227 }
228 module_exit(mtd_stresstest_exit);
229
230 MODULE_DESCRIPTION("Stress test module");
231 MODULE_AUTHOR("Adrian Hunter");
232 MODULE_LICENSE("GPL");
233