1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Load ELF vmlinux file for the kexec_file_load syscall. 4 * 5 * Copyright (C) 2004 Adam Litke (agl@us.ibm.com) 6 * Copyright (C) 2004 IBM Corp. 7 * Copyright (C) 2005 R Sharada (sharada@in.ibm.com) 8 * Copyright (C) 2006 Mohan Kumar M (mohan@in.ibm.com) 9 * Copyright (C) 2016 IBM Corporation 10 * 11 * Based on kexec-tools' kexec-elf-exec.c and kexec-elf-ppc64.c. 12 * Heavily modified for the kernel by 13 * Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>. 14 */ 15 16 #define pr_fmt(fmt) "kexec_elf: " fmt 17 18 #include <linux/elf.h> 19 #include <linux/kexec.h> 20 #include <linux/libfdt.h> 21 #include <linux/module.h> 22 #include <linux/of_fdt.h> 23 #include <linux/slab.h> 24 #include <linux/types.h> 25 26 static void *elf64_load(struct kimage *image, char *kernel_buf, 27 unsigned long kernel_len, char *initrd, 28 unsigned long initrd_len, char *cmdline, 29 unsigned long cmdline_len) 30 { 31 int ret; 32 unsigned int fdt_size; 33 unsigned long kernel_load_addr; 34 unsigned long initrd_load_addr = 0, fdt_load_addr; 35 void *fdt; 36 const void *slave_code; 37 struct elfhdr ehdr; 38 struct kexec_elf_info elf_info; 39 struct kexec_buf kbuf = { .image = image, .buf_min = 0, 40 .buf_max = ppc64_rma_size }; 41 struct kexec_buf pbuf = { .image = image, .buf_min = 0, 42 .buf_max = ppc64_rma_size, .top_down = true, 43 .mem = KEXEC_BUF_MEM_UNKNOWN }; 44 45 ret = kexec_build_elf_info(kernel_buf, kernel_len, &ehdr, &elf_info); 46 if (ret) 47 goto out; 48 49 ret = kexec_elf_load(image, &ehdr, &elf_info, &kbuf, &kernel_load_addr); 50 if (ret) 51 goto out; 52 53 pr_debug("Loaded the kernel at 0x%lx\n", kernel_load_addr); 54 55 ret = kexec_load_purgatory(image, &pbuf); 56 if (ret) { 57 pr_err("Loading purgatory failed.\n"); 58 goto out; 59 } 60 61 pr_debug("Loaded purgatory at 0x%lx\n", pbuf.mem); 62 63 if (initrd != NULL) { 64 kbuf.buffer = initrd; 65 kbuf.bufsz = kbuf.memsz = initrd_len; 66 kbuf.buf_align = PAGE_SIZE; 67 kbuf.top_down = false; 68 kbuf.mem = KEXEC_BUF_MEM_UNKNOWN; 69 ret = kexec_add_buffer(&kbuf); 70 if (ret) 71 goto out; 72 initrd_load_addr = kbuf.mem; 73 74 pr_debug("Loaded initrd at 0x%lx\n", initrd_load_addr); 75 } 76 77 fdt_size = fdt_totalsize(initial_boot_params) * 2; 78 fdt = kmalloc(fdt_size, GFP_KERNEL); 79 if (!fdt) { 80 pr_err("Not enough memory for the device tree.\n"); 81 ret = -ENOMEM; 82 goto out; 83 } 84 ret = fdt_open_into(initial_boot_params, fdt, fdt_size); 85 if (ret < 0) { 86 pr_err("Error setting up the new device tree.\n"); 87 ret = -EINVAL; 88 goto out; 89 } 90 91 ret = setup_new_fdt(image, fdt, initrd_load_addr, initrd_len, cmdline); 92 if (ret) 93 goto out; 94 95 fdt_pack(fdt); 96 97 kbuf.buffer = fdt; 98 kbuf.bufsz = kbuf.memsz = fdt_size; 99 kbuf.buf_align = PAGE_SIZE; 100 kbuf.top_down = true; 101 kbuf.mem = KEXEC_BUF_MEM_UNKNOWN; 102 ret = kexec_add_buffer(&kbuf); 103 if (ret) 104 goto out; 105 fdt_load_addr = kbuf.mem; 106 107 pr_debug("Loaded device tree at 0x%lx\n", fdt_load_addr); 108 109 slave_code = elf_info.buffer + elf_info.proghdrs[0].p_offset; 110 ret = setup_purgatory(image, slave_code, fdt, kernel_load_addr, 111 fdt_load_addr); 112 if (ret) 113 pr_err("Error setting up the purgatory.\n"); 114 115 out: 116 kexec_free_elf_info(&elf_info); 117 118 /* Make kimage_file_post_load_cleanup free the fdt buffer for us. */ 119 return ret ? ERR_PTR(ret) : fdt; 120 } 121 122 const struct kexec_file_ops kexec_elf64_ops = { 123 .probe = kexec_elf_probe, 124 .load = elf64_load, 125 }; 126