configs.c 2.0 KB

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  1. // SPDX-License-Identifier: GPL-2.0-or-later
  2. /*
  3. * kernel/configs.c
  4. * Echo the kernel .config file used to build the kernel
  5. *
  6. * Copyright (C) 2002 Khalid Aziz <khalid_aziz@hp.com>
  7. * Copyright (C) 2002 Randy Dunlap <rdunlap@xenotime.net>
  8. * Copyright (C) 2002 Al Stone <ahs3@fc.hp.com>
  9. * Copyright (C) 2002 Hewlett-Packard Company
  10. */
  11. #include <linux/kernel.h>
  12. #include <linux/module.h>
  13. #include <linux/proc_fs.h>
  14. #include <linux/seq_file.h>
  15. #include <linux/init.h>
  16. #include <linux/uaccess.h>
  17. /*
  18. * "IKCFG_ST" and "IKCFG_ED" are used to extract the config data from
  19. * a binary kernel image or a module. See scripts/extract-ikconfig.
  20. */
  21. asm (
  22. " .pushsection .rodata, \"a\" \n"
  23. " .ascii \"IKCFG_ST\" \n"
  24. " .global kernel_config_data \n"
  25. "kernel_config_data: \n"
  26. " .incbin \"kernel/config_data.gz\" \n"
  27. " .global kernel_config_data_end \n"
  28. "kernel_config_data_end: \n"
  29. " .ascii \"IKCFG_ED\" \n"
  30. " .popsection \n"
  31. );
  32. #ifdef CONFIG_IKCONFIG_PROC
  33. extern char kernel_config_data;
  34. extern char kernel_config_data_end;
  35. static ssize_t
  36. ikconfig_read_current(struct file *file, char __user *buf,
  37. size_t len, loff_t * offset)
  38. {
  39. return simple_read_from_buffer(buf, len, offset,
  40. &kernel_config_data,
  41. &kernel_config_data_end -
  42. &kernel_config_data);
  43. }
  44. static const struct proc_ops config_gz_proc_ops = {
  45. .proc_read = ikconfig_read_current,
  46. .proc_lseek = default_llseek,
  47. };
  48. static int __init ikconfig_init(void)
  49. {
  50. struct proc_dir_entry *entry;
  51. /* create the current config file */
  52. entry = proc_create("config.gz", S_IFREG | S_IRUGO, NULL,
  53. &config_gz_proc_ops);
  54. if (!entry)
  55. return -ENOMEM;
  56. proc_set_size(entry, &kernel_config_data_end - &kernel_config_data);
  57. return 0;
  58. }
  59. static void __exit ikconfig_cleanup(void)
  60. {
  61. remove_proc_entry("config.gz", NULL);
  62. }
  63. module_init(ikconfig_init);
  64. module_exit(ikconfig_cleanup);
  65. #endif /* CONFIG_IKCONFIG_PROC */
  66. MODULE_LICENSE("GPL");
  67. MODULE_AUTHOR("Randy Dunlap");
  68. MODULE_DESCRIPTION("Echo the kernel .config file used to build the kernel");