1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * arch/arm/kernel/crash_dump.c 4 * 5 * Copyright (C) 2010 Nokia Corporation. 6 * Author: Mika Westerberg 7 * 8 * This code is taken from arch/x86/kernel/crash_dump_64.c 9 * Created by: Hariprasad Nellitheertha (hari@in.ibm.com) 10 * Copyright (C) IBM Corporation, 2004. All rights reserved 11 */ 12 13 #include <linux/errno.h> 14 #include <linux/crash_dump.h> 15 #include <linux/uaccess.h> 16 #include <linux/io.h> 17 #include <linux/uio.h> 18 19 ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn, 20 size_t csize, unsigned long offset) 21 { 22 void *vaddr; 23 24 if (!csize) 25 return 0; 26 27 vaddr = ioremap(__pfn_to_phys(pfn), PAGE_SIZE); 28 if (!vaddr) 29 return -ENOMEM; 30 31 csize = copy_to_iter(vaddr + offset, csize, iter); 32 33 iounmap(vaddr); 34 return csize; 35 } 36