1// SPDX-License-Identifier: GPL-2.0
 2#include <linux/crash_dump.h>
 3#include <linux/io.h>
 4#include <linux/uio.h>
 5
 6ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn,
 7			 size_t csize, unsigned long offset)
 8{
 9	void *vaddr;
10
11	if (!csize)
12		return 0;
13
14	vaddr = memremap(__pfn_to_phys(pfn), PAGE_SIZE, MEMREMAP_WB);
15	if (!vaddr)
16		return -ENOMEM;
17
18	csize = copy_to_iter(vaddr + offset, csize, iter);
19
20	memunmap(vaddr);
21
22	return csize;
23}

 1// SPDX-License-Identifier: GPL-2.0
 2#include <linux/crash_dump.h>
 3#include <linux/io.h>
 4#include <linux/uio.h>
 5
 6ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn,
 7			 size_t csize, unsigned long offset)
 8{
 9	void *vaddr;
10
11	if (!csize)
12		return 0;
13
14	vaddr = memremap(__pfn_to_phys(pfn), PAGE_SIZE, MEMREMAP_WB);
15	if (!vaddr)
16		return -ENOMEM;
17
18	csize = copy_to_iter(vaddr + offset, csize, iter);
19
20	memunmap(vaddr);
21
22	return csize;
23}