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 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 */ 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 goto out_err; 153 } 154 155 /* trim it */ 156 fdt_pack(dtb); 157 dtb_len = fdt_totalsize(dtb); 158 kbuf.buffer = dtb; 159 kbuf.bufsz = dtb_len; 160 kbuf.mem = KEXEC_BUF_MEM_UNKNOWN; 161 kbuf.memsz = dtb_len; 162 /* not across 2MB boundary */ 163 kbuf.buf_align = SZ_2M; 164 kbuf.buf_max = ULONG_MAX; 165 kbuf.top_down = true; 166 167 ret = kexec_add_buffer(&kbuf); 168 if (ret) 169 goto out_err; 170 image->arch.dtb = dtb; 171 image->arch.dtb_mem = kbuf.mem; 172 173 pr_debug("Loaded dtb at 0x%lx bufsz=0x%lx memsz=0x%lx\n", 174 kbuf.mem, kbuf.bufsz, kbuf.memsz); 175 176 return 0; 177 178 out_err: 179 image->nr_segments = orig_segments; 180 kvfree(dtb); 181 return ret; 182 } 183