[PATCH 6/10] drivers/mtd: Use DIV_ROUND_UP

Julia Lawall julia at diku.dk
Sat Aug 2 11:14:21 EDT 2008


From: Julia Lawall <julia at diku.dk>

The kernel.h macro DIV_ROUND_UP performs the computation (((n) + (d) - 1) /
(d)) but is perhaps more readable.

An extract of the semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@haskernel@
@@

#include <linux/kernel.h>

@depends on haskernel@
expression n,d;
@@

(
- (n + d - 1) / d
+ DIV_ROUND_UP(n,d)
|
- (n + (d - 1)) / d
+ DIV_ROUND_UP(n,d)
)

@depends on haskernel@
expression n,d;
@@

- DIV_ROUND_UP((n),d)
+ DIV_ROUND_UP(n,d)

@depends on haskernel@
expression n,d;
@@

- DIV_ROUND_UP(n,(d))
+ DIV_ROUND_UP(n,d)
// </smpl>

Signed-off-by: Julia Lawall <julia at diku.dk>

---
 drivers/mtd/chips/cfi_cmdset_0001.c |    2 +-
 drivers/mtd/chips/gen_probe.c       |    2 +-
 drivers/mtd/ssfdc.c                 |    3 +--
 3 files changed, 3 insertions(+), 4 deletions(-)

diff -u -p a/drivers/mtd/chips/cfi_cmdset_0001.c b/drivers/mtd/chips/cfi_cmdset_0001.c
--- a/drivers/mtd/chips/cfi_cmdset_0001.c
+++ b/drivers/mtd/chips/cfi_cmdset_0001.c
@@ -1640,7 +1640,7 @@ static int __xipram do_write_buffer(stru
 
 	/* Figure out the number of words to write */
 	word_gap = (-adr & (map_bankwidth(map)-1));
-	words = (len - word_gap + map_bankwidth(map) - 1) / map_bankwidth(map);
+	words = DIV_ROUND_UP(len - word_gap, map_bankwidth(map));
 	if (!word_gap) {
 		words--;
 	} else {
diff -u -p a/drivers/mtd/chips/gen_probe.c b/drivers/mtd/chips/gen_probe.c
--- a/drivers/mtd/chips/gen_probe.c
+++ b/drivers/mtd/chips/gen_probe.c
@@ -111,7 +111,7 @@ static struct cfi_private *genprobe_iden
 		max_chips = 1;
 	}
 
-	mapsize = sizeof(long) * ( (max_chips + BITS_PER_LONG-1) / BITS_PER_LONG );
+	mapsize = sizeof(long) * DIV_ROUND_UP(max_chips, BITS_PER_LONG);
 	chip_map = kzalloc(mapsize, GFP_KERNEL);
 	if (!chip_map) {
 		printk(KERN_WARNING "%s: kmalloc failed for CFI chip map\n", map->name);
diff -u -p a/drivers/mtd/ssfdc.c b/drivers/mtd/ssfdc.c
--- a/drivers/mtd/ssfdc.c
+++ b/drivers/mtd/ssfdc.c
@@ -321,8 +321,7 @@ static void ssfdcr_add_mtd(struct mtd_bl
 	DEBUG(MTD_DEBUG_LEVEL1,
 		"SSFDC_RO: cis_block=%d,erase_size=%d,map_len=%d,n_zones=%d\n",
 		ssfdc->cis_block, ssfdc->erase_size, ssfdc->map_len,
-		(ssfdc->map_len + MAX_PHYS_BLK_PER_ZONE - 1) /
-		MAX_PHYS_BLK_PER_ZONE);
+		DIV_ROUND_UP(ssfdc->map_len, MAX_PHYS_BLK_PER_ZONE));
 
 	/* Set geometry */
 	ssfdc->heads = 16;



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