1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * kexec_file for LoongArch 4 * 5 * Author: Youling Tang <tangyouling@kylinos.cn> 6 * Copyright (C) 2025 KylinSoft Corporation. 7 * 8 * Most code is derived from LoongArch 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/memblock.h> 17 #include <linux/slab.h> 18 #include <linux/string.h> 19 #include <linux/types.h> 20 #include <linux/vmalloc.h> 21 #include <asm/bootinfo.h> 22 23 const struct kexec_file_ops * const kexec_file_loaders[] = { 24 &kexec_efi_ops, 25 &kexec_elf_ops, 26 NULL 27 }; 28 29 int arch_kimage_file_post_load_cleanup(struct kimage *image) 30 { 31 vfree(image->elf_headers); 32 image->elf_headers = NULL; 33 image->elf_headers_sz = 0; 34 35 return kexec_image_post_load_cleanup_default(image); 36 } 37 38 /* Add the "kexec_file" command line parameter to command line. */ 39 static void cmdline_add_loader(unsigned long *cmdline_tmplen, char *modified_cmdline) 40 { 41 int loader_strlen; 42 43 loader_strlen = sprintf(modified_cmdline + (*cmdline_tmplen), "kexec_file "); 44 *cmdline_tmplen += loader_strlen; 45 } 46 47 /* Add the "initrd=start,size" command line parameter to command line. */ 48 static void cmdline_add_initrd(struct kimage *image, unsigned long *cmdline_tmplen, 49 char *modified_cmdline, unsigned long initrd) 50 { 51 int initrd_strlen; 52 53 initrd_strlen = sprintf(modified_cmdline + (*cmdline_tmplen), "initrd=0x%lx,0x%lx ", 54 initrd, image->initrd_buf_len); 55 *cmdline_tmplen += initrd_strlen; 56 } 57 58 /* 59 * Try to add the initrd to the image. If it is not possible to find valid 60 * locations, this function will undo changes to the image and return non zero. 61 */ 62 int load_other_segments(struct kimage *image, 63 unsigned long kernel_load_addr, unsigned long kernel_size, 64 char *initrd, unsigned long initrd_len, char *cmdline, unsigned long cmdline_len) 65 { 66 int ret = 0; 67 unsigned long cmdline_tmplen = 0; 68 unsigned long initrd_load_addr = 0; 69 unsigned long orig_segments = image->nr_segments; 70 char *modified_cmdline = NULL; 71 struct kexec_buf kbuf; 72 73 kbuf.image = image; 74 /* Don't allocate anything below the kernel */ 75 kbuf.buf_min = kernel_load_addr + kernel_size; 76 77 modified_cmdline = kzalloc(COMMAND_LINE_SIZE, GFP_KERNEL); 78 if (!modified_cmdline) 79 return -EINVAL; 80 81 cmdline_add_loader(&cmdline_tmplen, modified_cmdline); 82 /* Ensure it's null terminated */ 83 modified_cmdline[COMMAND_LINE_SIZE - 1] = '\0'; 84 85 /* Load initrd */ 86 if (initrd) { 87 kbuf.buffer = initrd; 88 kbuf.bufsz = initrd_len; 89 kbuf.mem = KEXEC_BUF_MEM_UNKNOWN; 90 kbuf.memsz = initrd_len; 91 kbuf.buf_align = 0; 92 /* within 1GB-aligned window of up to 32GB in size */ 93 kbuf.buf_max = round_down(kernel_load_addr, SZ_1G) + (unsigned long)SZ_1G * 32; 94 kbuf.top_down = false; 95 96 ret = kexec_add_buffer(&kbuf); 97 if (ret < 0) 98 goto out_err; 99 initrd_load_addr = kbuf.mem; 100 101 kexec_dprintk("Loaded initrd at 0x%lx bufsz=0x%lx memsz=0x%lx\n", 102 initrd_load_addr, kbuf.bufsz, kbuf.memsz); 103 104 /* Add the initrd=start,size parameter to the command line */ 105 cmdline_add_initrd(image, &cmdline_tmplen, modified_cmdline, initrd_load_addr); 106 } 107 108 if (cmdline_len + cmdline_tmplen > COMMAND_LINE_SIZE) { 109 pr_err("Appending command line exceeds COMMAND_LINE_SIZE\n"); 110 ret = -EINVAL; 111 goto out_err; 112 } 113 114 memcpy(modified_cmdline + cmdline_tmplen, cmdline, cmdline_len); 115 cmdline = modified_cmdline; 116 image->arch.cmdline_ptr = (unsigned long)cmdline; 117 118 return 0; 119 120 out_err: 121 image->nr_segments = orig_segments; 122 kfree(modified_cmdline); 123 return ret; 124 } 125