[PATCH v3 08/11] mtd: mtd_pagetest: convert to use prandom library

Akinobu Mita
2012-11-13T13:37:53Z

This removes home-brewed pseudo-random number generator and use
prandom library.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Artem Bityutskiy <dedekind1@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: linux-mtd@lists.infradead.org
---
* v3
- rename 'random32_*' to 'prandom_*'

* v2
- rename prandom32_get_bytes to random32_get_bytes_state

drivers/mtd/tests/mtd_pagetest.c | 43 ++++++++++++----------------------------
1 file changed, 13 insertions(+), 30 deletions(-)

diff --git a/drivers/mtd/tests/mtd_pagetest.c b/drivers/mtd/tests/mtd_pagetest.c
index 252ddb0..4197280 100644
--- a/drivers/mtd/tests/mtd_pagetest.c
+++ b/drivers/mtd/tests/mtd_pagetest.c
@@ -27,6 +27,7 @@
#include <linux/mtd/mtd.h>
#include <linux/slab.h>
#include <linux/sched.h>
+#include <linux/random.h>

#define PRINT_PREF KERN_INFO "mtd_pagetest: "

@@ -45,26 +46,7 @@ static int bufsize;
static int ebcnt;
static int pgcnt;
static int errcnt;
-static unsigned long next = 1;
-
-static inline unsigned int simple_rand(void)
-{
- next = next * 1103515245 + 12345;
- return (unsigned int)((next / 65536) % 32768);
-}
-
-static inline void simple_srand(unsigned long seed)
-{
- next = seed;
-}
-
-static void set_random_data(unsigned char *buf, size_t len)
-{
- size_t i;
-
- for (i = 0; i < len; ++i)
- buf[i] = simple_rand();
-}
+static struct rnd_state rnd_state;

static int erase_eraseblock(int ebnum)
{
@@ -98,7 +80,7 @@ static int write_eraseblock(int ebnum)
size_t written;
loff_t addr = ebnum * mtd->erasesize;

- set_random_data(writebuf, mtd->erasesize);
+ prandom_bytes_state(&rnd_state, writebuf, mtd->erasesize);
cond_resched();
err = mtd_write(mtd, addr, mtd->erasesize, &written, writebuf);
if (err || written != mtd->erasesize)
@@ -124,7 +106,7 @@ static int verify_eraseblock(int ebnum)
for (i = 0; i < ebcnt && bbt[ebcnt - i - 1]; ++i)
addrn -= mtd->erasesize;

- set_random_data(writebuf, mtd->erasesize);
+ prandom_bytes_state(&rnd_state, writebuf, mtd->erasesize);
for (j = 0; j < pgcnt - 1; ++j, addr += pgsize) {
/* Do a read to set the internal dataRAMs to different data */
err = mtd_read(mtd, addr0, bufsize, &read, twopages);
@@ -160,7 +142,8 @@ static int verify_eraseblock(int ebnum)
}
/* Check boundary between eraseblocks */
if (addr <= addrn - pgsize - pgsize && !bbt[ebnum + 1]) {
- unsigned long oldnext = next;
+ struct rnd_state old_state = rnd_state;
+
/* Do a read to set the internal dataRAMs to different data */
err = mtd_read(mtd, addr0, bufsize, &read, twopages);
if (mtd_is_bitflip(err))
@@ -188,13 +171,13 @@ static int verify_eraseblock(int ebnum)
return err;
}
memcpy(boundary, writebuf + mtd->erasesize - pgsize, pgsize);
- set_random_data(boundary + pgsize, pgsize);
+ prandom_bytes_state(&rnd_state, boundary + pgsize, pgsize);
if (memcmp(twopages, boundary, bufsize)) {
printk(PRINT_PREF "error: verify failed at %#llx\n",
(long long)addr);
errcnt += 1;
}
- next = oldnext;
+ rnd_state = old_state;
}
return err;
}
@@ -326,7 +309,7 @@ static int erasecrosstest(void)
return err;

printk(PRINT_PREF "writing 1st page of block %d\n", ebnum);
- set_random_data(writebuf, pgsize);
+ prandom_bytes_state(&rnd_state, writebuf, pgsize);
strcpy(writebuf, "There is no data like this!");
err = mtd_write(mtd, addr0, pgsize, &written, writebuf);
if (err || written != pgsize) {
@@ -359,7 +342,7 @@ static int erasecrosstest(void)
return err;

printk(PRINT_PREF "writing 1st page of block %d\n", ebnum);
- set_random_data(writebuf, pgsize);
+ prandom_bytes_state(&rnd_state, writebuf, pgsize);
strcpy(writebuf, "There is no data like this!");
err = mtd_write(mtd, addr0, pgsize, &written, writebuf);
if (err || written != pgsize) {
@@ -417,7 +400,7 @@ static int erasetest(void)
return err;

printk(PRINT_PREF "writing 1st page of block %d\n", ebnum);
- set_random_data(writebuf, pgsize);
+ prandom_bytes_state(&rnd_state, writebuf, pgsize);
err = mtd_write(mtd, addr0, pgsize, &written, writebuf);
if (err || written != pgsize) {
printk(PRINT_PREF "error: write failed at %#llx\n",
@@ -565,7 +548,7 @@ static int __init mtd_pagetest_init(void)
printk(PRINT_PREF "erased %u eraseblocks\n", i);

/* Write all eraseblocks */
- simple_srand(1);
+ prandom_seed_state(&rnd_state, 1);
printk(PRINT_PREF "writing whole device\n");
for (i = 0; i < ebcnt; ++i) {
if (bbt[i])
@@ -580,7 +563,7 @@ static int __init mtd_pagetest_init(void)
printk(PRINT_PREF "written %u eraseblocks\n", i);

/* Check all eraseblocks */
- simple_srand(1);
+ prandom_seed_state(&rnd_state, 1);
printk(PRINT_PREF "verifying all eraseblocks\n");
for (i = 0; i < ebcnt; ++i) {
if (bbt[i])
--
1.7.11.7