1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * kexec_file for arm64
4 *
5 * Copyright (C) 2018 Linaro Limited
6 * Author: AKASHI Takahiro <takahiro.akashi@linaro.org>
7 *
8 * Most code is derived from arm64 port of kexec-tools
9 */
10
11 #define pr_fmt(fmt) "kexec_file: " fmt
12
13 #include <linux/ioport.h>
14 #include <linux/kernel.h>
15 #include <linux/kexec.h>
16 #include <linux/libfdt.h>
17 #include <linux/memblock.h>
18 #include <linux/of.h>
19 #include <linux/of_fdt.h>
20 #include <linux/slab.h>
21 #include <linux/string.h>
22 #include <linux/types.h>
23 #include <linux/vmalloc.h>
24
25 const struct kexec_file_ops * const kexec_file_loaders[] = {
26 &kexec_image_ops,
27 NULL
28 };
29
arch_kimage_file_post_load_cleanup(struct kimage * image)30 int arch_kimage_file_post_load_cleanup(struct kimage *image)
31 {
32 kvfree(image->arch.dtb);
33 image->arch.dtb = NULL;
34
35 vfree(image->elf_headers);
36 image->elf_headers = NULL;
37 image->elf_headers_sz = 0;
38
39 return kexec_image_post_load_cleanup_default(image);
40 }
41
prepare_elf_headers(void ** addr,unsigned long * sz)42 static int prepare_elf_headers(void **addr, unsigned long *sz)
43 {
44 struct crash_mem *cmem;
45 unsigned int nr_ranges;
46 int ret;
47 u64 i;
48 phys_addr_t start, end;
49
50 nr_ranges = 1; /* for exclusion of crashkernel region */
51 for_each_mem_range(i, &start, &end)
52 nr_ranges++;
53
54 cmem = kmalloc(struct_size(cmem, ranges, nr_ranges), GFP_KERNEL);
55 if (!cmem)
56 return -ENOMEM;
57
58 cmem->max_nr_ranges = nr_ranges;
59 cmem->nr_ranges = 0;
60 for_each_mem_range(i, &start, &end) {
61 cmem->ranges[cmem->nr_ranges].start = start;
62 cmem->ranges[cmem->nr_ranges].end = end - 1;
63 cmem->nr_ranges++;
64 }
65
66 /* Exclude crashkernel region */
67 ret = crash_exclude_mem_range(cmem, crashk_res.start, crashk_res.end);
68
69 if (!ret)
70 ret = crash_prepare_elf64_headers(cmem, true, addr, sz);
71
72 kfree(cmem);
73 return ret;
74 }
75
76 /*
77 * Tries to add the initrd and DTB to the image. If it is not possible to find
78 * valid locations, this function will undo changes to the image and return non
79 * zero.
80 */
load_other_segments(struct kimage * image,unsigned long kernel_load_addr,unsigned long kernel_size,char * initrd,unsigned long initrd_len,char * cmdline)81 int load_other_segments(struct kimage *image,
82 unsigned long kernel_load_addr,
83 unsigned long kernel_size,
84 char *initrd, unsigned long initrd_len,
85 char *cmdline)
86 {
87 struct kexec_buf kbuf;
88 void *headers, *dtb = NULL;
89 unsigned long headers_sz, initrd_load_addr = 0, dtb_len,
90 orig_segments = image->nr_segments;
91 int ret = 0;
92
93 kbuf.image = image;
94 /* not allocate anything below the kernel */
95 kbuf.buf_min = kernel_load_addr + kernel_size;
96
97 /* load elf core header */
98 if (image->type == KEXEC_TYPE_CRASH) {
99 ret = prepare_elf_headers(&headers, &headers_sz);
100 if (ret) {
101 pr_err("Preparing elf core header failed\n");
102 goto out_err;
103 }
104
105 kbuf.buffer = headers;
106 kbuf.bufsz = headers_sz;
107 kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
108 kbuf.memsz = headers_sz;
109 kbuf.buf_align = SZ_64K; /* largest supported page size */
110 kbuf.buf_max = ULONG_MAX;
111 kbuf.top_down = true;
112
113 ret = kexec_add_buffer(&kbuf);
114 if (ret) {
115 vfree(headers);
116 goto out_err;
117 }
118 image->elf_headers = headers;
119 image->elf_load_addr = kbuf.mem;
120 image->elf_headers_sz = headers_sz;
121
122 pr_debug("Loaded elf core header at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
123 image->elf_load_addr, kbuf.bufsz, kbuf.memsz);
124 }
125
126 /* load initrd */
127 if (initrd) {
128 kbuf.buffer = initrd;
129 kbuf.bufsz = initrd_len;
130 kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
131 kbuf.memsz = initrd_len;
132 kbuf.buf_align = 0;
133 /* within 1GB-aligned window of up to 32GB in size */
134 kbuf.buf_max = round_down(kernel_load_addr, SZ_1G)
135 + (unsigned long)SZ_1G * 32;
136 kbuf.top_down = false;
137
138 ret = kexec_add_buffer(&kbuf);
139 if (ret)
140 goto out_err;
141 initrd_load_addr = kbuf.mem;
142
143 pr_debug("Loaded initrd at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
144 initrd_load_addr, kbuf.bufsz, kbuf.memsz);
145 }
146
147 /* load dtb */
148 dtb = of_kexec_alloc_and_setup_fdt(image, initrd_load_addr,
149 initrd_len, cmdline, 0);
150 if (!dtb) {
151 pr_err("Preparing for new dtb failed\n");
152 ret = -EINVAL;
153 goto out_err;
154 }
155
156 /* trim it */
157 fdt_pack(dtb);
158 dtb_len = fdt_totalsize(dtb);
159 kbuf.buffer = dtb;
160 kbuf.bufsz = dtb_len;
161 kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
162 kbuf.memsz = dtb_len;
163 /* not across 2MB boundary */
164 kbuf.buf_align = SZ_2M;
165 kbuf.buf_max = ULONG_MAX;
166 kbuf.top_down = true;
167
168 ret = kexec_add_buffer(&kbuf);
169 if (ret)
170 goto out_err;
171 image->arch.dtb = dtb;
172 image->arch.dtb_mem = kbuf.mem;
173
174 pr_debug("Loaded dtb at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
175 kbuf.mem, kbuf.bufsz, kbuf.memsz);
176
177 return 0;
178
179 out_err:
180 image->nr_segments = orig_segments;
181 kvfree(dtb);
182 return ret;
183 }
184