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 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 42 #ifdef CONFIG_CRASH_DUMP 43 static int prepare_elf_headers(void **addr, unsigned long *sz) 44 { 45 struct crash_mem *cmem; 46 unsigned int nr_ranges; 47 int ret; 48 u64 i; 49 phys_addr_t start, end; 50 51 nr_ranges = 2; /* for exclusion of crashkernel region */ 52 for_each_mem_range(i, &start, &end) 53 nr_ranges++; 54 55 cmem = kmalloc(struct_size(cmem, ranges, nr_ranges), GFP_KERNEL); 56 if (!cmem) 57 return -ENOMEM; 58 59 cmem->max_nr_ranges = nr_ranges; 60 cmem->nr_ranges = 0; 61 for_each_mem_range(i, &start, &end) { 62 cmem->ranges[cmem->nr_ranges].start = start; 63 cmem->ranges[cmem->nr_ranges].end = end - 1; 64 cmem->nr_ranges++; 65 } 66 67 /* Exclude crashkernel region */ 68 ret = crash_exclude_mem_range(cmem, crashk_res.start, crashk_res.end); 69 if (ret) 70 goto out; 71 72 if (crashk_low_res.end) { 73 ret = crash_exclude_mem_range(cmem, crashk_low_res.start, crashk_low_res.end); 74 if (ret) 75 goto out; 76 } 77 78 ret = crash_prepare_elf64_headers(cmem, true, addr, sz); 79 80 out: 81 kfree(cmem); 82 return ret; 83 } 84 #endif 85 86 /* 87 * Tries to add the initrd and DTB to the image. If it is not possible to find 88 * valid locations, this function will undo changes to the image and return non 89 * zero. 90 */ 91 int load_other_segments(struct kimage *image, 92 unsigned long kernel_load_addr, 93 unsigned long kernel_size, 94 char *initrd, unsigned long initrd_len, 95 char *cmdline) 96 { 97 struct kexec_buf kbuf; 98 void *dtb = NULL; 99 unsigned long initrd_load_addr = 0, dtb_len, 100 orig_segments = image->nr_segments; 101 int ret = 0; 102 103 kbuf.image = image; 104 /* not allocate anything below the kernel */ 105 kbuf.buf_min = kernel_load_addr + kernel_size; 106 107 #ifdef CONFIG_CRASH_DUMP 108 /* load elf core header */ 109 void *headers; 110 unsigned long headers_sz; 111 if (image->type == KEXEC_TYPE_CRASH) { 112 ret = prepare_elf_headers(&headers, &headers_sz); 113 if (ret) { 114 pr_err("Preparing elf core header failed\n"); 115 goto out_err; 116 } 117 118 kbuf.buffer = headers; 119 kbuf.bufsz = headers_sz; 120 kbuf.mem = KEXEC_BUF_MEM_UNKNOWN; 121 kbuf.memsz = headers_sz; 122 kbuf.buf_align = SZ_64K; /* largest supported page size */ 123 kbuf.buf_max = ULONG_MAX; 124 kbuf.top_down = true; 125 126 ret = kexec_add_buffer(&kbuf); 127 if (ret) { 128 vfree(headers); 129 goto out_err; 130 } 131 image->elf_headers = headers; 132 image->elf_load_addr = kbuf.mem; 133 image->elf_headers_sz = headers_sz; 134 135 kexec_dprintk("Loaded elf core header at 0x%lx bufsz=0x%lx memsz=0x%lx\n", 136 image->elf_load_addr, kbuf.bufsz, kbuf.memsz); 137 } 138 #endif 139 140 /* load initrd */ 141 if (initrd) { 142 kbuf.buffer = initrd; 143 kbuf.bufsz = initrd_len; 144 kbuf.mem = KEXEC_BUF_MEM_UNKNOWN; 145 kbuf.memsz = initrd_len; 146 kbuf.buf_align = 0; 147 /* within 1GB-aligned window of up to 32GB in size */ 148 kbuf.buf_max = round_down(kernel_load_addr, SZ_1G) 149 + (unsigned long)SZ_1G * 32; 150 kbuf.top_down = false; 151 152 ret = kexec_add_buffer(&kbuf); 153 if (ret) 154 goto out_err; 155 initrd_load_addr = kbuf.mem; 156 157 kexec_dprintk("Loaded initrd at 0x%lx bufsz=0x%lx memsz=0x%lx\n", 158 initrd_load_addr, kbuf.bufsz, kbuf.memsz); 159 } 160 161 /* load dtb */ 162 dtb = of_kexec_alloc_and_setup_fdt(image, initrd_load_addr, 163 initrd_len, cmdline, 0); 164 if (!dtb) { 165 pr_err("Preparing for new dtb failed\n"); 166 ret = -EINVAL; 167 goto out_err; 168 } 169 170 /* trim it */ 171 fdt_pack(dtb); 172 dtb_len = fdt_totalsize(dtb); 173 kbuf.buffer = dtb; 174 kbuf.bufsz = dtb_len; 175 kbuf.mem = KEXEC_BUF_MEM_UNKNOWN; 176 kbuf.memsz = dtb_len; 177 /* not across 2MB boundary */ 178 kbuf.buf_align = SZ_2M; 179 kbuf.buf_max = ULONG_MAX; 180 kbuf.top_down = true; 181 182 ret = kexec_add_buffer(&kbuf); 183 if (ret) 184 goto out_err; 185 image->arch.dtb = dtb; 186 image->arch.dtb_mem = kbuf.mem; 187 188 kexec_dprintk("Loaded dtb at 0x%lx bufsz=0x%lx memsz=0x%lx\n", 189 kbuf.mem, kbuf.bufsz, kbuf.memsz); 190 191 return 0; 192 193 out_err: 194 image->nr_segments = orig_segments; 195 kvfree(dtb); 196 return ret; 197 } 198