1 /* 2 * kernel/configs.c 3 * Echo the kernel .config file used to build the kernel 4 * 5 * Copyright (C) 2002 Khalid Aziz <khalid_aziz@hp.com> 6 * Copyright (C) 2002 Randy Dunlap <rdunlap@xenotime.net> 7 * Copyright (C) 2002 Al Stone <ahs3@fc.hp.com> 8 * Copyright (C) 2002 Hewlett-Packard Company 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License as published by 12 * the Free Software Foundation; either version 2 of the License, or (at 13 * your option) any later version. 14 * 15 * This program is distributed in the hope that it will be useful, but 16 * WITHOUT ANY WARRANTY; without even the implied warranty of 17 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or 18 * NON INFRINGEMENT. See the GNU General Public License for more 19 * details. 20 * 21 * You should have received a copy of the GNU General Public License 22 * along with this program; if not, write to the Free Software 23 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 24 */ 25 26 #include <linux/kernel.h> 27 #include <linux/module.h> 28 #include <linux/proc_fs.h> 29 #include <linux/seq_file.h> 30 #include <linux/init.h> 31 #include <asm/uaccess.h> 32 33 /**************************************************/ 34 /* the actual current config file */ 35 36 /* 37 * Define kernel_config_data and kernel_config_data_size, which contains the 38 * wrapped and compressed configuration file. The file is first compressed 39 * with gzip and then bounded by two eight byte magic numbers to allow 40 * extraction from a binary kernel image: 41 * 42 * IKCFG_ST 43 * <image> 44 * IKCFG_ED 45 */ 46 #define MAGIC_START "IKCFG_ST" 47 #define MAGIC_END "IKCFG_ED" 48 #include "config_data.h" 49 50 51 #define MAGIC_SIZE (sizeof(MAGIC_START) - 1) 52 #define kernel_config_data_size \ 53 (sizeof(kernel_config_data) - 1 - MAGIC_SIZE * 2) 54 55 #ifdef CONFIG_IKCONFIG_PROC 56 57 static ssize_t 58 ikconfig_read_current(struct file *file, char __user *buf, 59 size_t len, loff_t * offset) 60 { 61 return simple_read_from_buffer(buf, len, offset, 62 kernel_config_data + MAGIC_SIZE, 63 kernel_config_data_size); 64 } 65 66 static const struct file_operations ikconfig_file_ops = { 67 .owner = THIS_MODULE, 68 .read = ikconfig_read_current, 69 .llseek = default_llseek, 70 }; 71 72 static int __init ikconfig_init(void) 73 { 74 struct proc_dir_entry *entry; 75 76 /* create the current config file */ 77 entry = proc_create("config.gz", S_IFREG | S_IRUGO, NULL, 78 &ikconfig_file_ops); 79 if (!entry) 80 return -ENOMEM; 81 82 proc_set_size(entry, kernel_config_data_size); 83 84 return 0; 85 } 86 87 static void __exit ikconfig_cleanup(void) 88 { 89 remove_proc_entry("config.gz", NULL); 90 } 91 92 module_init(ikconfig_init); 93 module_exit(ikconfig_cleanup); 94 95 #endif /* CONFIG_IKCONFIG_PROC */ 96 97 MODULE_LICENSE("GPL"); 98 MODULE_AUTHOR("Randy Dunlap"); 99 MODULE_DESCRIPTION("Echo the kernel .config file used to build the kernel"); 100