blob: 670e4ce818223c2d2ba91ad76084fdd78369ac04 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0-only
* Routines for doing kexec-based kdump
* Copyright (C) 2017 Linaro Limited
* Author: AKASHI Takahiro <>
#include <linux/crash_dump.h>
#include <linux/errno.h>
#include <linux/io.h>
#include <linux/uio.h>
#include <asm/memory.h>
ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn,
size_t csize, unsigned long offset)
void *vaddr;
if (!csize)
return 0;
vaddr = memremap(__pfn_to_phys(pfn), PAGE_SIZE, MEMREMAP_WB);
if (!vaddr)
return -ENOMEM;
csize = copy_to_iter(vaddr + offset, csize, iter);
return csize;
* elfcorehdr_read - read from ELF core header
* @buf: buffer where the data is placed
* @count: number of bytes to read
* @ppos: address in the memory
* This function reads @count bytes from elf core header which exists
* on crash dump kernel's memory.
ssize_t elfcorehdr_read(char *buf, size_t count, u64 *ppos)
memcpy(buf, phys_to_virt((phys_addr_t)*ppos), count);
*ppos += count;
return count;