1/* 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> 12#include <linux/module.h> 13 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 22EXPORT_SYMBOL(kmap); 23 24void kunmap(struct page *page) 25{ 26 if (in_interrupt()) 27 BUG(); 28 if (!PageHighMem(page)) 29 return; 30 kunmap_high(page); 31} 32 33EXPORT_SYMBOL(kunmap); 34 35struct page *kmap_atomic_to_page(void *ptr) 36{ 37 return virt_to_page(ptr); 38} 39