blob: eadd07658075c3bc942ead2ee3d4d77f0b0803ec [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/* highmem.c: arch-specific highmem stuff
2 *
3 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11#include <linux/highmem.h>
David Howells40234402006-01-08 01:01:19 -080012#include <linux/module.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070013
14void *kmap(struct page *page)
15{
16 might_sleep();
17 if (!PageHighMem(page))
18 return page_address(page);
19 return kmap_high(page);
20}
21
David Howells40234402006-01-08 01:01:19 -080022EXPORT_SYMBOL(kmap);
23
Linus Torvalds1da177e2005-04-16 15:20:36 -070024void kunmap(struct page *page)
25{
26 if (in_interrupt())
27 BUG();
28 if (!PageHighMem(page))
29 return;
30 kunmap_high(page);
31}
32
David Howells40234402006-01-08 01:01:19 -080033EXPORT_SYMBOL(kunmap);
34
Linus Torvalds1da177e2005-04-16 15:20:36 -070035struct page *kmap_atomic_to_page(void *ptr)
36{
37 return virt_to_page(ptr);
38}