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Commit 80ad89a0 authored by Wu Fengguang's avatar Wu Fengguang Committed by Linus Torvalds
Browse files

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



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

Signed-off-by: default avatarWu 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: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 7fabaddd

drivers/char/mem.c

+22 −27
Original line number Diff line number Diff line
@@ -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);

	}