projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 1da177e4 LT |
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> | |
| f4b09ebc | 6 | * Copyright (C) 2002 Randy Dunlap <rdunlap@xenotime.net> |
| 1da177e4 LT |
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 | ||
| 1da177e4 LT |
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 | /**************************************************/ | |
| 58 | /* globals and useful constants */ | |
| 59 | ||
| 60 | static ssize_t | |
| 61 | ikconfig_read_current(struct file *file, char __user *buf, | |
| 62 | size_t len, loff_t * offset) | |
| 63 | { | |
| 64 | loff_t pos = *offset; | |
| 65 | ssize_t count; | |
| 66 | ||
| 67 | if (pos >= kernel_config_data_size) | |
| 68 | return 0; | |
| 69 | ||
| 70 | count = min(len, (size_t)(kernel_config_data_size - pos)); | |
| 71 | if (copy_to_user(buf, kernel_config_data + MAGIC_SIZE + pos, count)) | |
| 72 | return -EFAULT; | |
| 73 | ||
| 74 | *offset += count; | |
| 75 | return count; | |
| 76 | } | |
| 77 | ||
| 78 | static struct file_operations ikconfig_file_ops = { | |
| 79 | .owner = THIS_MODULE, | |
| 80 | .read = ikconfig_read_current, | |
| 81 | }; | |
| 82 | ||
| 83 | /***************************************************/ | |
| 84 | /* ikconfig_init: start up everything we need to */ | |
| 85 | ||
| 86 | static int __init ikconfig_init(void) | |
| 87 | { | |
| 88 | struct proc_dir_entry *entry; | |
| 89 | ||
| 90 | /* create the current config file */ | |
| 91 | entry = create_proc_entry("config.gz", S_IFREG | S_IRUGO, | |
| 92 | &proc_root); | |
| 93 | if (!entry) | |
| 94 | return -ENOMEM; | |
| 95 | ||
| 96 | entry->proc_fops = &ikconfig_file_ops; | |
| 97 | entry->size = kernel_config_data_size; | |
| 98 | ||
| 99 | return 0; | |
| 100 | } | |
| 101 | ||
| 102 | /***************************************************/ | |
| 103 | /* ikconfig_cleanup: clean up our mess */ | |
| 104 | ||
| 105 | static void __exit ikconfig_cleanup(void) | |
| 106 | { | |
| 107 | remove_proc_entry("config.gz", &proc_root); | |
| 108 | } | |
| 109 | ||
| 110 | module_init(ikconfig_init); | |
| 111 | module_exit(ikconfig_cleanup); | |
| 112 | ||
| 113 | MODULE_LICENSE("GPL"); | |
| 114 | MODULE_AUTHOR("Randy Dunlap"); | |
| 115 | MODULE_DESCRIPTION("Echo the kernel .config file used to build the kernel"); | |
| 116 | ||
| 117 | #endif /* CONFIG_IKCONFIG_PROC */ |