[PATCH] mtd/onenand: use string library

From: Akinobu Mita
Date: Fri Jan 27 2012 - 09:26:34 EST


- Use memchr_inv to check if the data contains all 0xFF bytes.
It is faster than looping for each byte.

- Use memcmp to compare memory areas

Signed-off-by: Akinobu Mita <akinobu.mita@xxxxxxxxx>
Cc: David Woodhouse <dwmw2@xxxxxxxxxxxxx>
Cc: Kyungmin Park <kyungmin.park@xxxxxxxxxxx>
Cc: linux-mtd@xxxxxxxxxxxxxxxxxxx
---
drivers/mtd/onenand/onenand_base.c | 8 ++------
drivers/mtd/onenand/onenand_bbt.c | 10 +++-------
2 files changed, 5 insertions(+), 13 deletions(-)

diff --git a/drivers/mtd/onenand/onenand_base.c b/drivers/mtd/onenand/onenand_base.c
index a061bc1..374605f 100644
--- a/drivers/mtd/onenand/onenand_base.c
+++ b/drivers/mtd/onenand/onenand_base.c
@@ -3673,7 +3673,7 @@ static void flexonenand_get_size(struct mtd_info *mtd)
static int flexonenand_check_blocks_erased(struct mtd_info *mtd, int start, int end)
{
struct onenand_chip *this = mtd->priv;
- int i, ret;
+ int ret;
int block;
struct mtd_oob_ops ops = {
.mode = MTD_OPS_PLACE_OOB,
@@ -3699,11 +3699,7 @@ static int flexonenand_check_blocks_erased(struct mtd_info *mtd, int start, int
if (ret)
return ret;

- for (i = 0; i < mtd->oobsize; i++)
- if (this->oob_buf[i] != 0xff)
- break;
-
- if (i != mtd->oobsize) {
+ if (memchr_inv(this->oob_buf, 0xff, mtd->oobsize)) {
printk(KERN_WARNING "%s: Block %d not erased.\n",
__func__, block);
return 1;
diff --git a/drivers/mtd/onenand/onenand_bbt.c b/drivers/mtd/onenand/onenand_bbt.c
index 66fe3b7..8b1277b 100644
--- a/drivers/mtd/onenand/onenand_bbt.c
+++ b/drivers/mtd/onenand/onenand_bbt.c
@@ -32,14 +32,10 @@
*/
static int check_short_pattern(uint8_t *buf, int len, int paglen, struct nand_bbt_descr *td)
{
- int i;
- uint8_t *p = buf;
-
/* Compare the pattern */
- for (i = 0; i < td->len; i++) {
- if (p[i] != td->pattern[i])
- return -1;
- }
+ if (memcmp(buf, td->pattern, td->len))
+ return -1;
+
return 0;
}

--
1.7.4.4

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