| 1 | // SPDX-License-Identifier: GPL-2.0 |
|---|---|
| 2 | /* |
| 3 | * This code comes from arch/arm64/kernel/crash_dump.c |
| 4 | * Created by: AKASHI Takahiro <takahiro.akashi@linaro.org> |
| 5 | * Copyright (C) 2017 Linaro Limited |
| 6 | */ |
| 7 | |
| 8 | #include <linux/crash_dump.h> |
| 9 | #include <linux/io.h> |
| 10 | #include <linux/uio.h> |
| 11 | |
| 12 | ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn, |
| 13 | size_t csize, unsigned long offset) |
| 14 | { |
| 15 | void *vaddr; |
| 16 | |
| 17 | if (!csize) |
| 18 | return 0; |
| 19 | |
| 20 | vaddr = memremap(__pfn_to_phys(pfn), PAGE_SIZE, flags: MEMREMAP_WB); |
| 21 | if (!vaddr) |
| 22 | return -ENOMEM; |
| 23 | |
| 24 | csize = copy_to_iter(addr: vaddr + offset, bytes: csize, i: iter); |
| 25 | |
| 26 | memunmap(addr: vaddr); |
| 27 | return csize; |
| 28 | } |
| 29 |