[PATCH 1/3] devmem: remove redundant test on len

From: Wu Fengguang
Date: Thu Sep 10 2009 - 22:33:49 EST


The len test in write_kmem() is always true, so can be reduced.

CC: Marcelo Tosatti <mtosatti@xxxxxxxxxx>
CC: Greg Kroah-Hartman <gregkh@xxxxxxx>
CC: Mark Brown <broonie@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
CC: Johannes Berg <johannes@xxxxxxxxxxxxxxxx>
CC: Avi Kivity <avi@xxxxxxxxxxxx>
Signed-off-by: Wu Fengguang <fengguang.wu@xxxxxxxxx>
---
drivers/char/mem.c | 14 ++++++--------
1 file changed, 6 insertions(+), 8 deletions(-)

--- linux.orig/drivers/char/mem.c
+++ linux/drivers/char/mem.c
@@ -580,18 +580,16 @@ static ssize_t write_kmem(struct file *
while (count > 0) {
int len = count;

if (len > PAGE_SIZE)
len = PAGE_SIZE;
- if (len) {
- written = copy_from_user(kbuf, buf, len);
- if (written) {
- if (wrote + virtr)
- break;
- free_page((unsigned long)kbuf);
- return -EFAULT;
- }
+ written = copy_from_user(kbuf, buf, len);
+ if (written) {
+ if (wrote + virtr)
+ break;
+ free_page((unsigned long)kbuf);
+ return -EFAULT;
}
len = vwrite(kbuf, (char *)p, len);
count -= len;
buf += len;
virtr += len;

--

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