root.c 3.9 KB

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  1. /*
  2. * linux/fs/proc/root.c
  3. *
  4. * Copyright (C) 1991, 1992 Linus Torvalds
  5. *
  6. * proc root directory handling functions
  7. */
  8. #include <asm/uaccess.h>
  9. #include <linux/errno.h>
  10. #include <linux/time.h>
  11. #include <linux/proc_fs.h>
  12. #include <linux/stat.h>
  13. #include <linux/init.h>
  14. #include <linux/sched.h>
  15. #include <linux/module.h>
  16. #include <linux/bitops.h>
  17. #include <linux/smp_lock.h>
  18. #include <linux/mount.h>
  19. #include "internal.h"
  20. struct proc_dir_entry *proc_net, *proc_net_stat, *proc_bus, *proc_root_fs, *proc_root_driver;
  21. static int proc_get_sb(struct file_system_type *fs_type,
  22. int flags, const char *dev_name, void *data, struct vfsmount *mnt)
  23. {
  24. if (proc_mnt) {
  25. /* Seed the root directory with a pid so it doesn't need
  26. * to be special in base.c. I would do this earlier but
  27. * the only task alive when /proc is mounted the first time
  28. * is the init_task and it doesn't have any pids.
  29. */
  30. struct proc_inode *ei;
  31. ei = PROC_I(proc_mnt->mnt_sb->s_root->d_inode);
  32. if (!ei->pid)
  33. ei->pid = find_get_pid(1);
  34. }
  35. return get_sb_single(fs_type, flags, data, proc_fill_super, mnt);
  36. }
  37. static struct file_system_type proc_fs_type = {
  38. .name = "proc",
  39. .get_sb = proc_get_sb,
  40. .kill_sb = kill_anon_super,
  41. };
  42. void __init proc_root_init(void)
  43. {
  44. int err = proc_init_inodecache();
  45. if (err)
  46. return;
  47. err = register_filesystem(&proc_fs_type);
  48. if (err)
  49. return;
  50. proc_mnt = kern_mount(&proc_fs_type);
  51. err = PTR_ERR(proc_mnt);
  52. if (IS_ERR(proc_mnt)) {
  53. unregister_filesystem(&proc_fs_type);
  54. return;
  55. }
  56. proc_misc_init();
  57. proc_net = proc_mkdir("net", NULL);
  58. proc_net_stat = proc_mkdir("net/stat", NULL);
  59. #ifdef CONFIG_SYSVIPC
  60. proc_mkdir("sysvipc", NULL);
  61. #endif
  62. proc_root_fs = proc_mkdir("fs", NULL);
  63. proc_root_driver = proc_mkdir("driver", NULL);
  64. proc_mkdir("fs/nfsd", NULL); /* somewhere for the nfsd filesystem to be mounted */
  65. #if defined(CONFIG_SUN_OPENPROMFS) || defined(CONFIG_SUN_OPENPROMFS_MODULE)
  66. /* just give it a mountpoint */
  67. proc_mkdir("openprom", NULL);
  68. #endif
  69. proc_tty_init();
  70. #ifdef CONFIG_PROC_DEVICETREE
  71. proc_device_tree_init();
  72. #endif
  73. proc_bus = proc_mkdir("bus", NULL);
  74. proc_sys_init();
  75. }
  76. static int proc_root_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat
  77. )
  78. {
  79. generic_fillattr(dentry->d_inode, stat);
  80. stat->nlink = proc_root.nlink + nr_processes();
  81. return 0;
  82. }
  83. static struct dentry *proc_root_lookup(struct inode * dir, struct dentry * dentry, struct nameidata *nd)
  84. {
  85. if (!proc_lookup(dir, dentry, nd)) {
  86. return NULL;
  87. }
  88. return proc_pid_lookup(dir, dentry, nd);
  89. }
  90. static int proc_root_readdir(struct file * filp,
  91. void * dirent, filldir_t filldir)
  92. {
  93. unsigned int nr = filp->f_pos;
  94. int ret;
  95. lock_kernel();
  96. if (nr < FIRST_PROCESS_ENTRY) {
  97. int error = proc_readdir(filp, dirent, filldir);
  98. if (error <= 0) {
  99. unlock_kernel();
  100. return error;
  101. }
  102. filp->f_pos = FIRST_PROCESS_ENTRY;
  103. }
  104. unlock_kernel();
  105. ret = proc_pid_readdir(filp, dirent, filldir);
  106. return ret;
  107. }
  108. /*
  109. * The root /proc directory is special, as it has the
  110. * <pid> directories. Thus we don't use the generic
  111. * directory handling functions for that..
  112. */
  113. static const struct file_operations proc_root_operations = {
  114. .read = generic_read_dir,
  115. .readdir = proc_root_readdir,
  116. };
  117. /*
  118. * proc root can do almost nothing..
  119. */
  120. static const struct inode_operations proc_root_inode_operations = {
  121. .lookup = proc_root_lookup,
  122. .getattr = proc_root_getattr,
  123. };
  124. /*
  125. * This is the root "inode" in the /proc tree..
  126. */
  127. struct proc_dir_entry proc_root = {
  128. .low_ino = PROC_ROOT_INO,
  129. .namelen = 5,
  130. .name = "/proc",
  131. .mode = S_IFDIR | S_IRUGO | S_IXUGO,
  132. .nlink = 2,
  133. .proc_iops = &proc_root_inode_operations,
  134. .proc_fops = &proc_root_operations,
  135. .parent = &proc_root,
  136. };
  137. EXPORT_SYMBOL(proc_symlink);
  138. EXPORT_SYMBOL(proc_mkdir);
  139. EXPORT_SYMBOL(create_proc_entry);
  140. EXPORT_SYMBOL(remove_proc_entry);
  141. EXPORT_SYMBOL(proc_root);
  142. EXPORT_SYMBOL(proc_root_fs);
  143. EXPORT_SYMBOL(proc_net);
  144. EXPORT_SYMBOL(proc_net_stat);
  145. EXPORT_SYMBOL(proc_bus);
  146. EXPORT_SYMBOL(proc_root_driver);