arch/sh/kernel/crash_dump.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *      crash_dump.c - Memory preserving reboot related code.
   4  *
   5  *      Created by: Hariprasad Nellitheertha (hari@in.ibm.com)
   6  *      Copyright (C) IBM Corporation, 2004. All rights reserved
   7  */
   8 #include <linux/errno.h>
   9 #include <linux/crash_dump.h>
  10 #include <linux/io.h>
  11 #include <linux/uio.h>
  12 #include <linux/uaccess.h>
  13
  14 ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn,
  15                          size_t csize, unsigned long offset)
  16 {
  17         void  __iomem *vaddr;
  18
  19         if (!csize)
  20                 return 0;
  21
  22         vaddr = ioremap(pfn << PAGE_SHIFT, PAGE_SIZE);
  23         csize = copy_to_iter(vaddr + offset, csize, iter);
  24         iounmap(vaddr);
  25
  26         return csize;
  27 }