LXR linux/arch/x86/include/asm/crash-driver.h

   1#ifndef _ASM_X86_CRASH_DRIVER_H
   2#define _ASM_X86_CRASH_DRIVER_H
   3
   4/*
   5 * linux/include/x86/crash-driver.h
   6 *
   7 * Copyright (c) 2004 Red Hat, Inc. All rights reserved.
   8 *
   9 * This program is free software; you can redistribute it and/or modify
  10 * it under the terms of the GNU General Public License as published by
  11 * the Free Software Foundation; either version 2, or (at your option)
  12 * any later version.
  13 *
  14 * This program is distributed in the hope that it will be useful,
  15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 * GNU General Public License for more details.
  18 *
  19 * You should have received a copy of the GNU General Public License
  20 * along with this program; if not, write to the Free Software
  21 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  22 *
  23 */
  24
  25#ifdef __KERNEL__
  26
  27#include <linux/mm.h>
  28#include <linux/highmem.h>
  29#include <asm/mmzone.h>
  30
  31extern int page_is_ram(unsigned long);
  32
  33static inline void *
  34map_virtual(u64 offset, struct page **pp)
  35{
  36        struct page *page;
  37        unsigned long pfn;
  38        void *vaddr;
  39
  40        pfn = (unsigned long)(offset >> PAGE_SHIFT);
  41
  42        if (!page_is_ram(pfn)) {
  43                printk(KERN_INFO
  44                    "crash memory driver: !page_is_ram(pfn: %lx)\n", pfn);
  45                return NULL;
  46        }
  47
  48        if (!pfn_valid(pfn)) {
  49                printk(KERN_INFO
  50                    "crash memory driver: invalid pfn: %lx )\n", pfn);
  51                return NULL;
  52        }
  53
  54        page = pfn_to_page(pfn);
  55
  56        vaddr = kmap(page);
  57        if (!vaddr) {
  58                printk(KERN_INFO
  59                    "crash memory driver: pfn: %lx kmap(page: %lx) failed\n",
  60                        pfn, (unsigned long)page);
  61                return NULL;
  62        }
  63
  64        *pp = page;
  65        return (vaddr + (offset & (PAGE_SIZE-1)));
  66}
  67
  68static inline void unmap_virtual(struct page *page)
  69{
  70        kunmap(page);
  71}
  72
  73#endif /* __KERNEL__ */
  74
  75#endif /* _ASM_X86_CRASH_DRIVER_H */
  76