1 #include <errno.h>
2 #include <fcntl.h>
3 #include <getopt.h>
4 #include <stdio.h>
5 #include <stdlib.h>
6 #include <string.h>
7 #include <sys/mman.h>
8 #include <sys/stat.h>
9 #include <sys/syscall.h>
10 #include <sys/types.h>
11 #include <sys/wait.h>
12 #include <unistd.h>
13
14 #include "kexec.h"
15
16 // Offsets same as in kernel asm/kexec.h
17 #define KEXEC_ARM_ATAGS_OFFSET 0x1000
18 #define KEXEC_ARM_ZIMAGE_OFFSET 0x8000
19
20 #define MEMORY_SIZE 0x0800000
21 // Physical buffer address cannot overlap with other regions
22 #define START_ADDRESS 0x44000000
23
24 #define ROUND_TO_PAGE(address, pagesize) (((address) + (pagesize)-1) & (~((pagesize)-1)))
25
26 /*
27 * Gives file position and resets current position to begining of file
28 */
get_file_size(int f)29 int get_file_size(int f) {
30 struct stat st;
31 fstat(f, &st);
32 return st.st_size;
33 }
34
test_kexeccall()35 int test_kexeccall() {
36 int rv;
37
38 rv = kexec_load(0, 0, NULL, KEXEC_ARCH_DEFAULT);
39
40 if (rv != 0) {
41 printf("ERROR: kexec_load: %d \n", errno);
42 return 1;
43 }
44
45 printf("Kexec test: Success \n");
46
47 return 0;
48 }
49
usage(void)50 void usage(void) {
51 fprintf(stderr,
52 "usage: kexecload [ <option> ] <atags path> <kernel path>\n"
53 "\n"
54 "options:\n"
55 " -t tests syscall\n"
56 " -s <start address> specify start address of kernel\n");
57 }
58
59 /*
60 * Loads kexec into the kernel and sets kexec on crash
61 */
main(int argc,char * argv[])62 int main(int argc, char* argv[]) {
63 int rv;
64 int atag_file, zimage_file;
65 int atag_size, zimage_size;
66 void* atag_buffer;
67 void* zimage_buffer;
68 struct kexec_segment segment[2];
69 int page_size = getpagesize();
70 void* start_address = (void*)START_ADDRESS;
71 int c;
72
73 const struct option longopts[] = {{"start_address", required_argument, 0, 's'},
74 {"test", 0, 0, 't'},
75 {"help", 0, 0, 'h'},
76 {0, 0, 0, 0}};
77
78 while (1) {
79 c = getopt_long(argc, argv, "s:th", longopts, NULL);
80 if (c < 0) {
81 break;
82 }
83 /* Alphabetical cases */
84 switch (c) {
85 case 's':
86 start_address = (void*)strtoul(optarg, 0, 16);
87 break;
88 case 'h':
89 usage();
90 return 1;
91 case 't':
92 test_kexeccall();
93 return 1;
94 case '?':
95 return 1;
96 default:
97 abort();
98 }
99 }
100
101 argc -= optind;
102 argv += optind;
103
104 if (argc < 2) {
105 usage();
106 return 1;
107 }
108
109 atag_file = open(argv[0], O_RDONLY);
110 zimage_file = open(argv[1], O_RDONLY);
111
112 if (atag_file < 0 || zimage_file < 0) {
113 fprintf(stderr, "Error during opening of atag file or the zImage file %s\n",
114 strerror(errno));
115 return 1;
116 }
117
118 atag_size = ROUND_TO_PAGE(get_file_size(atag_file), page_size);
119 zimage_size = ROUND_TO_PAGE(get_file_size(zimage_file), page_size);
120
121 if (atag_size >= KEXEC_ARM_ZIMAGE_OFFSET - KEXEC_ARM_ATAGS_OFFSET) {
122 fprintf(stderr, "Atag file is too large\n");
123 return 1;
124 }
125
126 atag_buffer = (char*)mmap(NULL, atag_size, PROT_READ, MAP_POPULATE | MAP_PRIVATE, atag_file, 0);
127 zimage_buffer =
128 (char*)mmap(NULL, zimage_size, PROT_READ, MAP_POPULATE | MAP_PRIVATE, zimage_file, 0);
129
130 if (atag_buffer == MAP_FAILED || zimage_buffer == MAP_FAILED) {
131 fprintf(stderr, "Unable to map files into memory");
132 return 1;
133 }
134
135 segment[0].buf = zimage_buffer;
136 segment[0].bufsz = zimage_size;
137 segment[0].mem = (void*)((uintptr_t)start_address + KEXEC_ARM_ZIMAGE_OFFSET);
138 segment[0].memsz = zimage_size;
139
140 segment[1].buf = atag_buffer;
141 segment[1].bufsz = atag_size;
142 segment[1].mem = (void*)((uintptr_t)start_address + KEXEC_ARM_ATAGS_OFFSET);
143 segment[1].memsz = atag_size;
144
145 rv = kexec_load(((uintptr_t)start_address + KEXEC_ARM_ZIMAGE_OFFSET), 2, (void*)segment,
146 KEXEC_ARCH_DEFAULT | KEXEC_ON_CRASH);
147
148 if (rv != 0) {
149 fprintf(stderr, "Kexec_load returned non-zero exit code: %d with errno %d\n", rv, errno);
150 return 1;
151 }
152
153 printf("Done! Kexec loaded\n");
154 printf("New kernel should start at 0x%08x\n", START_ADDRESS + KEXEC_ARM_ZIMAGE_OFFSET);
155
156 return 0;
157 }
158