Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) // SPDX-License-Identifier: GPL-2.0-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3)  * Routines for doing kexec-based kdump
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5)  * Copyright (C) 2017 Linaro Limited
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6)  * Author: AKASHI Takahiro <takahiro.akashi@linaro.org>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9) #include <linux/crash_dump.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/errno.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/io.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/memblock.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/uaccess.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <asm/memory.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17)  * copy_oldmem_page() - copy one page from old kernel memory
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18)  * @pfn: page frame number to be copied
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19)  * @buf: buffer where the copied page is placed
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20)  * @csize: number of bytes to copy
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21)  * @offset: offset in bytes into the page
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22)  * @userbuf: if set, @buf is in a user address space
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24)  * This function copies one page from old kernel memory into buffer pointed by
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25)  * @buf. If @buf is in userspace, set @userbuf to %1. Returns number of bytes
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26)  * copied or negative error in case of failure.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) 			 size_t csize, unsigned long offset,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) 			 int userbuf)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 	void *vaddr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) 	if (!csize)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 	vaddr = memremap(__pfn_to_phys(pfn), PAGE_SIZE, MEMREMAP_WB);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 	if (!vaddr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 		return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) 	if (userbuf) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 		if (copy_to_user((char __user *)buf, vaddr + offset, csize)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) 			memunmap(vaddr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) 			return -EFAULT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) 	} else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) 		memcpy(buf, vaddr + offset, csize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) 	memunmap(vaddr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) 	return csize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56)  * elfcorehdr_read - read from ELF core header
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57)  * @buf: buffer where the data is placed
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58)  * @count: number of bytes to read
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59)  * @ppos: address in the memory
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61)  * This function reads @count bytes from elf core header which exists
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62)  * on crash dump kernel's memory.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) ssize_t elfcorehdr_read(char *buf, size_t count, u64 *ppos)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) 	memcpy(buf, phys_to_virt((phys_addr_t)*ppos), count);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) 	*ppos += count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) 	return count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) }