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 = 2; /* 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 if (ret)
69 goto out;
70
71 if (crashk_low_res.end) {
72 ret = crash_exclude_mem_range(cmem, crashk_low_res.start, crashk_low_res.end);
73 if (ret)
74 goto out;
75 }
76
77 ret = crash_prepare_elf64_headers(cmem, true, addr, sz);
78
79 out:
80 kfree(cmem);
81 return ret;
82 }
83
84 /*
85 * Tries to add the initrd and DTB to the image. If it is not possible to find
86 * valid locations, this function will undo changes to the image and return non
87 * zero.
88 */
load_other_segments(struct kimage * image,unsigned long kernel_load_addr,unsigned long kernel_size,char * initrd,unsigned long initrd_len,char * cmdline)89 int load_other_segments(struct kimage *image,
90 unsigned long kernel_load_addr,
91 unsigned long kernel_size,
92 char *initrd, unsigned long initrd_len,
93 char *cmdline)
94 {
95 struct kexec_buf kbuf;
96 void *headers, *dtb = NULL;
97 unsigned long headers_sz, initrd_load_addr = 0, dtb_len,
98 orig_segments = image->nr_segments;
99 int ret = 0;
100
101 kbuf.image = image;
102 /* not allocate anything below the kernel */
103 kbuf.buf_min = kernel_load_addr + kernel_size;
104
105 /* load elf core header */
106 if (image->type == KEXEC_TYPE_CRASH) {
107 ret = prepare_elf_headers(&headers, &headers_sz);
108 if (ret) {
109 pr_err("Preparing elf core header failed\n");
110 goto out_err;
111 }
112
113 kbuf.buffer = headers;
114 kbuf.bufsz = headers_sz;
115 kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
116 kbuf.memsz = headers_sz;
117 kbuf.buf_align = SZ_64K; /* largest supported page size */
118 kbuf.buf_max = ULONG_MAX;
119 kbuf.top_down = true;
120
121 ret = kexec_add_buffer(&kbuf);
122 if (ret) {
123 vfree(headers);
124 goto out_err;
125 }
126 image->elf_headers = headers;
127 image->elf_load_addr = kbuf.mem;
128 image->elf_headers_sz = headers_sz;
129
130 pr_debug("Loaded elf core header at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
131 image->elf_load_addr, kbuf.bufsz, kbuf.memsz);
132 }
133
134 /* load initrd */
135 if (initrd) {
136 kbuf.buffer = initrd;
137 kbuf.bufsz = initrd_len;
138 kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
139 kbuf.memsz = initrd_len;
140 kbuf.buf_align = 0;
141 /* within 1GB-aligned window of up to 32GB in size */
142 kbuf.buf_max = round_down(kernel_load_addr, SZ_1G)
143 + (unsigned long)SZ_1G * 32;
144 kbuf.top_down = false;
145
146 ret = kexec_add_buffer(&kbuf);
147 if (ret)
148 goto out_err;
149 initrd_load_addr = kbuf.mem;
150
151 pr_debug("Loaded initrd at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
152 initrd_load_addr, kbuf.bufsz, kbuf.memsz);
153 }
154
155 /* load dtb */
156 dtb = of_kexec_alloc_and_setup_fdt(image, initrd_load_addr,
157 initrd_len, cmdline, 0);
158 if (!dtb) {
159 pr_err("Preparing for new dtb failed\n");
160 ret = -EINVAL;
161 goto out_err;
162 }
163
164 /* trim it */
165 fdt_pack(dtb);
166 dtb_len = fdt_totalsize(dtb);
167 kbuf.buffer = dtb;
168 kbuf.bufsz = dtb_len;
169 kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
170 kbuf.memsz = dtb_len;
171 /* not across 2MB boundary */
172 kbuf.buf_align = SZ_2M;
173 kbuf.buf_max = ULONG_MAX;
174 kbuf.top_down = true;
175
176 ret = kexec_add_buffer(&kbuf);
177 if (ret)
178 goto out_err;
179 image->arch.dtb = dtb;
180 image->arch.dtb_mem = kbuf.mem;
181
182 pr_debug("Loaded dtb at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
183 kbuf.mem, kbuf.bufsz, kbuf.memsz);
184
185 return 0;
186
187 out_err:
188 image->nr_segments = orig_segments;
189 kvfree(dtb);
190 return ret;
191 }
192