boot/compressed/calc_vmlinuz_load_addr.c

0001 // SPDX-License-Identifier: GPL-2.0-or-later
0002 /*
0003  * Copyright (C) 2010 "Wu Zhangjin" <wuzhangjin@gmail.com>
0004  */
0005
0006 #include <sys/types.h>
0007 #include <sys/stat.h>
0008 #include <errno.h>
0009 #include <stdint.h>
0010 #include <stdio.h>
0011 #include <stdlib.h>
0012 #include <linux/sizes.h>
0013
0014 int main(int argc, char *argv[])
0015 {
0016     unsigned long long vmlinux_size, vmlinux_load_addr, vmlinuz_load_addr;
0017     struct stat sb;
0018
0019     if (argc != 3) {
0020         fprintf(stderr, "Usage: %s <pathname> <vmlinux_load_addr>\n",
0021                 argv[0]);
0022         return EXIT_FAILURE;
0023     }
0024
0025     if (stat(argv[1], &sb) == -1) {
0026         perror("stat");
0027         return EXIT_FAILURE;
0028     }
0029
0030     /* Convert hex characters to dec number */
0031     errno = 0;
0032     if (sscanf(argv[2], "%llx", &vmlinux_load_addr) != 1) {
0033         if (errno != 0)
0034             perror("sscanf");
0035         else
0036             fprintf(stderr, "No matching characters\n");
0037
0038         return EXIT_FAILURE;
0039     }
0040
0041     vmlinux_size = (uint64_t)sb.st_size;
0042     vmlinuz_load_addr = vmlinux_load_addr + vmlinux_size;
0043
0044     /*
0045      * Align with 64KB: KEXEC needs load sections to be aligned to PAGE_SIZE,
0046      * which may be as large as 64KB depending on the kernel configuration.
0047      */
0048
0049     vmlinuz_load_addr += (SZ_64K - vmlinux_size % SZ_64K);
0050
0051     printf("0x%llx\n", vmlinuz_load_addr);
0052
0053     return EXIT_SUCCESS;
0054 }