xref: /openbmc/linux/arch/s390/kernel/kexec_image.c (revision f32e5616)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Image loader for kexec_file_load system call.
4  *
5  * Copyright IBM Corp. 2018
6  *
7  * Author(s): Philipp Rudo <prudo@linux.vnet.ibm.com>
8  */
9 
10 #include <linux/errno.h>
11 #include <linux/kernel.h>
12 #include <linux/kexec.h>
13 #include <asm/setup.h>
14 
15 static int kexec_file_add_image_kernel(struct kimage *image,
16 				       struct s390_load_data *data,
17 				       char *kernel, unsigned long kernel_len)
18 {
19 	struct kexec_buf buf;
20 	int ret;
21 
22 	buf.image = image;
23 
24 	buf.buffer = kernel + STARTUP_NORMAL_OFFSET;
25 	buf.bufsz = kernel_len - STARTUP_NORMAL_OFFSET;
26 
27 	buf.mem = STARTUP_NORMAL_OFFSET;
28 	if (image->type == KEXEC_TYPE_CRASH)
29 		buf.mem += crashk_res.start;
30 	buf.memsz = buf.bufsz;
31 
32 	ret = kexec_add_buffer(&buf);
33 
34 	data->kernel_buf = kernel;
35 	data->memsz += buf.memsz + STARTUP_NORMAL_OFFSET;
36 
37 	return ret;
38 }
39 
40 static void *s390_image_load(struct kimage *image,
41 			     char *kernel, unsigned long kernel_len,
42 			     char *initrd, unsigned long initrd_len,
43 			     char *cmdline, unsigned long cmdline_len)
44 {
45 	struct s390_load_data data = {0};
46 	int ret;
47 
48 	ret = kexec_file_add_image_kernel(image, &data, kernel, kernel_len);
49 	if (ret)
50 		return ERR_PTR(ret);
51 
52 	if (initrd) {
53 		ret = kexec_file_add_initrd(image, &data, initrd, initrd_len);
54 		if (ret)
55 			return ERR_PTR(ret);
56 	}
57 
58 	ret = kexec_file_add_purgatory(image, &data);
59 	if (ret)
60 		return ERR_PTR(ret);
61 
62 	return kexec_file_update_kernel(image, &data);
63 }
64 
65 static int s390_image_probe(const char *buf, unsigned long len)
66 {
67 	/* Can't reliably tell if an image is valid.  Therefore give the
68 	 * user whatever he wants.
69 	 */
70 	return 0;
71 }
72 
73 const struct kexec_file_ops s390_kexec_image_ops = {
74 	.probe = s390_image_probe,
75 	.load = s390_image_load,
76 };
77