1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * RISC-V Kexec image loader
4 *
5 */
6
7 #define pr_fmt(fmt) "kexec_file(Image): " fmt
8
9 #include <linux/err.h>
10 #include <linux/errno.h>
11 #include <linux/kernel.h>
12 #include <linux/kexec.h>
13 #include <linux/pe.h>
14 #include <linux/string.h>
15 #include <asm/byteorder.h>
16 #include <asm/image.h>
17
image_probe(const char * kernel_buf,unsigned long kernel_len)18 static int image_probe(const char *kernel_buf, unsigned long kernel_len)
19 {
20 const struct riscv_image_header *h = (const struct riscv_image_header *)kernel_buf;
21
22 if (!h || kernel_len < sizeof(*h))
23 return -EINVAL;
24
25 /* According to Documentation/riscv/boot-image-header.rst,
26 * use "magic2" field to check when version >= 0.2.
27 */
28
29 if (h->version >= RISCV_HEADER_VERSION &&
30 memcmp(&h->magic2, RISCV_IMAGE_MAGIC2, sizeof(h->magic2)))
31 return -EINVAL;
32
33 return 0;
34 }
35
image_load(struct kimage * image,char * kernel,unsigned long kernel_len,char * initrd,unsigned long initrd_len,char * cmdline,unsigned long cmdline_len)36 static void *image_load(struct kimage *image,
37 char *kernel, unsigned long kernel_len,
38 char *initrd, unsigned long initrd_len,
39 char *cmdline, unsigned long cmdline_len)
40 {
41 struct riscv_image_header *h;
42 u64 flags;
43 bool be_image, be_kernel;
44 struct kexec_buf kbuf;
45 int ret;
46
47 /* Check Image header */
48 h = (struct riscv_image_header *)kernel;
49 if (!h->image_size) {
50 ret = -EINVAL;
51 goto out;
52 }
53
54 /* Check endianness */
55 flags = le64_to_cpu(h->flags);
56 be_image = riscv_image_flag_field(flags, RISCV_IMAGE_FLAG_BE);
57 be_kernel = IS_ENABLED(CONFIG_CPU_BIG_ENDIAN);
58 if (be_image != be_kernel) {
59 ret = -EINVAL;
60 goto out;
61 }
62
63 /* Load the kernel image */
64 kbuf.image = image;
65 kbuf.buf_min = 0;
66 kbuf.buf_max = ULONG_MAX;
67 kbuf.top_down = false;
68
69 kbuf.buffer = kernel;
70 kbuf.bufsz = kernel_len;
71 kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
72 kbuf.memsz = le64_to_cpu(h->image_size);
73 kbuf.buf_align = le64_to_cpu(h->text_offset);
74
75 ret = kexec_add_buffer(&kbuf);
76 if (ret) {
77 pr_err("Error add kernel image ret=%d\n", ret);
78 goto out;
79 }
80
81 image->start = kbuf.mem;
82
83 pr_info("Loaded kernel at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
84 kbuf.mem, kbuf.bufsz, kbuf.memsz);
85
86 ret = load_extra_segments(image, kbuf.mem, kbuf.memsz,
87 initrd, initrd_len, cmdline, cmdline_len);
88
89 out:
90 return ret ? ERR_PTR(ret) : NULL;
91 }
92
93 const struct kexec_file_ops image_kexec_ops = {
94 .probe = image_probe,
95 .load = image_load,
96 };
97