summaryrefslogtreecommitdiff
path: root/drivers/mtd/nand/nand_bbt.c
diff options
context:
space:
mode:
authorBrian Norris <computersforpeace@gmail.com>2012-06-22 16:35:44 -0700
committerDavid Woodhouse <David.Woodhouse@intel.com>2012-09-29 14:51:13 +0100
commit491ed06f334955578f0c43d298c46ea1a7ea9e1b (patch)
tree0522c7baadf16d60488c1861eef084b91c0b9b6f /drivers/mtd/nand/nand_bbt.c
parent7b5a2d40978fbb046b99b4030ce2785b66a451a5 (diff)
mtd: nand_bbt: use string library
Some nand_bbt code can be shortened by using memcmp() and memchr_inv(). As an added bonus, there is a possible performance benefit. Borrowed some code from Akinobu Mita. Signed-off-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Diffstat (limited to 'drivers/mtd/nand/nand_bbt.c')
-rw-r--r--drivers/mtd/nand/nand_bbt.c27
1 files changed, 9 insertions, 18 deletions
diff --git a/drivers/mtd/nand/nand_bbt.c b/drivers/mtd/nand/nand_bbt.c
index e23115be079e..f5839f06cece 100644
--- a/drivers/mtd/nand/nand_bbt.c
+++ b/drivers/mtd/nand/nand_bbt.c
@@ -68,6 +68,7 @@
#include <linux/delay.h>
#include <linux/vmalloc.h>
#include <linux/export.h>
+#include <linux/string.h>
static int check_pattern_no_oob(uint8_t *buf, struct nand_bbt_descr *td)
{
@@ -89,19 +90,16 @@ static int check_pattern_no_oob(uint8_t *buf, struct nand_bbt_descr *td)
*/
static int check_pattern(uint8_t *buf, int len, int paglen, struct nand_bbt_descr *td)
{
- int i, end = 0;
+ int end = 0;
uint8_t *p = buf;
if (td->options & NAND_BBT_NO_OOB)
return check_pattern_no_oob(buf, td);
end = paglen + td->offs;
- if (td->options & NAND_BBT_SCANEMPTY) {
- for (i = 0; i < end; i++) {
- if (p[i] != 0xff)
- return -1;
- }
- }
+ if (td->options & NAND_BBT_SCANEMPTY)
+ if (memchr_inv(p, 0xff, end))
+ return -1;
p += end;
/* Compare the pattern */
@@ -111,10 +109,8 @@ static int check_pattern(uint8_t *buf, int len, int paglen, struct nand_bbt_desc
if (td->options & NAND_BBT_SCANEMPTY) {
p += td->len;
end += td->len;
- for (i = end; i < len; i++) {
- if (*p++ != 0xff)
- return -1;
- }
+ if (memchr_inv(p, 0xff, len - end))
+ return -1;
}
return 0;
}
@@ -130,14 +126,9 @@ static int check_pattern(uint8_t *buf, int len, int paglen, struct nand_bbt_desc
*/
static int check_short_pattern(uint8_t *buf, struct nand_bbt_descr *td)
{
- int i;
- uint8_t *p = buf;
-
/* Compare the pattern */
- for (i = 0; i < td->len; i++) {
- if (p[td->offs + i] != td->pattern[i])
- return -1;
- }
+ if (memcmp(buf + td->offs, td->pattern, td->len))
+ return -1;
return 0;
}