LXR linux/arch/arc/include/asm/highmem.h

   1/*
   2 * Copyright (C) 2015 Synopsys, Inc. (www.synopsys.com)
   3 *
   4 * This program is free software; you can redistribute it and/or modify
   5 * it under the terms of the GNU General Public License version 2 as
   6 * published by the Free Software Foundation.
   7 *
   8 */
   9
  10#ifndef _ASM_HIGHMEM_H
  11#define _ASM_HIGHMEM_H
  12
  13#ifdef CONFIG_HIGHMEM
  14
  15#include <uapi/asm/page.h>
  16#include <asm/kmap_types.h>
  17
  18/* start after vmalloc area */
  19#define FIXMAP_BASE             (PAGE_OFFSET - FIXMAP_SIZE - PKMAP_SIZE)
  20#define FIXMAP_SIZE             PGDIR_SIZE      /* only 1 PGD worth */
  21#define KM_TYPE_NR              ((FIXMAP_SIZE >> PAGE_SHIFT)/NR_CPUS)
  22#define FIXMAP_ADDR(nr)         (FIXMAP_BASE + ((nr) << PAGE_SHIFT))
  23
  24/* start after fixmap area */
  25#define PKMAP_BASE              (FIXMAP_BASE + FIXMAP_SIZE)
  26#define PKMAP_SIZE              PGDIR_SIZE
  27#define LAST_PKMAP              (PKMAP_SIZE >> PAGE_SHIFT)
  28#define LAST_PKMAP_MASK         (LAST_PKMAP - 1)
  29#define PKMAP_ADDR(nr)          (PKMAP_BASE + ((nr) << PAGE_SHIFT))
  30#define PKMAP_NR(virt)          (((virt) - PKMAP_BASE) >> PAGE_SHIFT)
  31
  32#define kmap_prot               PAGE_KERNEL
  33
  34
  35#include <asm/cacheflush.h>
  36
  37extern void *kmap(struct page *page);
  38extern void *kmap_high(struct page *page);
  39extern void *kmap_atomic(struct page *page);
  40extern void __kunmap_atomic(void *kvaddr);
  41extern void kunmap_high(struct page *page);
  42
  43extern void kmap_init(void);
  44
  45static inline void flush_cache_kmaps(void)
  46{
  47        flush_cache_all();
  48}
  49
  50static inline void kunmap(struct page *page)
  51{
  52        BUG_ON(in_interrupt());
  53        if (!PageHighMem(page))
  54                return;
  55        kunmap_high(page);
  56}
  57
  58
  59#endif
  60
  61#endif
  62