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/dev/mem: remove the "written" variable in write_kmem() 

Also rename "len" to "sz". No behavior change.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Avi Kivity <avi@qumranet.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Wu Fengguang 2009-12-14 17:58:10 -08:00 committed by Linus Torvalds
parent 7fabaddd09
commit 80ad89a0ce
1 changed files with 22 additions and 27 deletions
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49
drivers/char/mem.c
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@ -440,19 +440,18 @@ static ssize_t read_kmem(struct file *file, char __user *buf,
if (!kbuf)
return -ENOMEM;
while (count > 0) {
int len = size_inside_page(p, count);
len = vread(kbuf, (char *)p, len);
if (!len)
sz = size_inside_page(p, count);
sz = vread(kbuf, (char *)p, sz);
if (!sz)
break;
if (copy_to_user(buf, kbuf, len)) {
if (copy_to_user(buf, kbuf, sz)) {
free_page((unsigned long)kbuf);
return -EFAULT;
}
count -= len;
buf += len;
read += len;
p += len;
count -= sz;
buf += sz;
read += sz;
p += sz;
}
free_page((unsigned long)kbuf);
}
@ -522,19 +521,14 @@ static ssize_t write_kmem(struct file * file, const char __user * buf,
unsigned long p = *ppos;
ssize_t wrote = 0;
ssize_t virtr = 0;
ssize_t written;
char * kbuf; /* k-addr because vwrite() takes vmlist_lock rwlock */
if (p < (unsigned long) high_memory) {
wrote = count;
if (count > (unsigned long) high_memory - p)
wrote = (unsigned long) high_memory - p;
written = do_write_kmem((void*)p, p, buf, wrote, ppos);
if (written != wrote)
return written;
wrote = written;
unsigned long to_write = min_t(unsigned long, count,
(unsigned long)high_memory - p);
wrote = do_write_kmem((void *)p, p, buf, to_write, ppos);
if (wrote != to_write)
return wrote;
p += wrote;
buf += wrote;
count -= wrote;
@ -545,20 +539,21 @@ static ssize_t write_kmem(struct file * file, const char __user * buf,
if (!kbuf)
return wrote ? wrote : -ENOMEM;
while (count > 0) {
int len = size_inside_page(p, count);
unsigned long sz = size_inside_page(p, count);
unsigned long n;
written = copy_from_user(kbuf, buf, len);
if (written) {
n = copy_from_user(kbuf, buf, sz);
if (n) {
if (wrote + virtr)
break;
free_page((unsigned long)kbuf);
return -EFAULT;
}
len = vwrite(kbuf, (char *)p, len);
count -= len;
buf += len;
virtr += len;
p += len;
sz = vwrite(kbuf, (char *)p, sz);
count -= sz;
buf += sz;
virtr += sz;
p += sz;
}
free_page((unsigned long)kbuf);
}