1 /* 2 * linux/fs/proc/root.c 3 * 4 * Copyright (C) 1991, 1992 Linus Torvalds 5 * 6 * proc root directory handling functions 7 */ 8 9 #include <asm/uaccess.h> 10 11 #include <linux/errno.h> 12 #include <linux/time.h> 13 #include <linux/proc_fs.h> 14 #include <linux/stat.h> 15 #include <linux/init.h> 16 #include <linux/sched.h> 17 #include <linux/module.h> 18 #include <linux/bitops.h> 19 #include <linux/smp_lock.h> 20 #include <linux/mount.h> 21 22 #include "internal.h" 23 24 struct proc_dir_entry *proc_net, *proc_net_stat, *proc_bus, *proc_root_fs, *proc_root_driver; 25 26 #ifdef CONFIG_SYSCTL 27 struct proc_dir_entry *proc_sys_root; 28 #endif 29 30 static int proc_get_sb(struct file_system_type *fs_type, 31 int flags, const char *dev_name, void *data, struct vfsmount *mnt) 32 { 33 if (proc_mnt) { 34 /* Seed the root directory with a pid so it doesn't need 35 * to be special in base.c. I would do this earlier but 36 * the only task alive when /proc is mounted the first time 37 * is the init_task and it doesn't have any pids. 38 */ 39 struct proc_inode *ei; 40 ei = PROC_I(proc_mnt->mnt_sb->s_root->d_inode); 41 if (!ei->pid) 42 ei->pid = find_get_pid(1); 43 } 44 return get_sb_single(fs_type, flags, data, proc_fill_super, mnt); 45 } 46 47 static struct file_system_type proc_fs_type = { 48 .name = "proc", 49 .get_sb = proc_get_sb, 50 .kill_sb = kill_anon_super, 51 }; 52 53 void __init proc_root_init(void) 54 { 55 int err = proc_init_inodecache(); 56 if (err) 57 return; 58 err = register_filesystem(&proc_fs_type); 59 if (err) 60 return; 61 proc_mnt = kern_mount(&proc_fs_type); 62 err = PTR_ERR(proc_mnt); 63 if (IS_ERR(proc_mnt)) { 64 unregister_filesystem(&proc_fs_type); 65 return; 66 } 67 proc_misc_init(); 68 proc_net = proc_mkdir("net", NULL); 69 proc_net_stat = proc_mkdir("net/stat", NULL); 70 71 #ifdef CONFIG_SYSVIPC 72 proc_mkdir("sysvipc", NULL); 73 #endif 74 #ifdef CONFIG_SYSCTL 75 proc_sys_root = proc_mkdir("sys", NULL); 76 #endif 77 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE) 78 proc_mkdir("sys/fs", NULL); 79 proc_mkdir("sys/fs/binfmt_misc", NULL); 80 #endif 81 proc_root_fs = proc_mkdir("fs", NULL); 82 proc_root_driver = proc_mkdir("driver", NULL); 83 proc_mkdir("fs/nfsd", NULL); /* somewhere for the nfsd filesystem to be mounted */ 84 #if defined(CONFIG_SUN_OPENPROMFS) || defined(CONFIG_SUN_OPENPROMFS_MODULE) 85 /* just give it a mountpoint */ 86 proc_mkdir("openprom", NULL); 87 #endif 88 proc_tty_init(); 89 #ifdef CONFIG_PROC_DEVICETREE 90 proc_device_tree_init(); 91 #endif 92 proc_bus = proc_mkdir("bus", NULL); 93 } 94 95 static int proc_root_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat 96 ) 97 { 98 generic_fillattr(dentry->d_inode, stat); 99 stat->nlink = proc_root.nlink + nr_processes(); 100 return 0; 101 } 102 103 static struct dentry *proc_root_lookup(struct inode * dir, struct dentry * dentry, struct nameidata *nd) 104 { 105 if (!proc_lookup(dir, dentry, nd)) { 106 return NULL; 107 } 108 109 return proc_pid_lookup(dir, dentry, nd); 110 } 111 112 static int proc_root_readdir(struct file * filp, 113 void * dirent, filldir_t filldir) 114 { 115 unsigned int nr = filp->f_pos; 116 int ret; 117 118 lock_kernel(); 119 120 if (nr < FIRST_PROCESS_ENTRY) { 121 int error = proc_readdir(filp, dirent, filldir); 122 if (error <= 0) { 123 unlock_kernel(); 124 return error; 125 } 126 filp->f_pos = FIRST_PROCESS_ENTRY; 127 } 128 unlock_kernel(); 129 130 ret = proc_pid_readdir(filp, dirent, filldir); 131 return ret; 132 } 133 134 /* 135 * The root /proc directory is special, as it has the 136 * <pid> directories. Thus we don't use the generic 137 * directory handling functions for that.. 138 */ 139 static struct file_operations proc_root_operations = { 140 .read = generic_read_dir, 141 .readdir = proc_root_readdir, 142 }; 143 144 /* 145 * proc root can do almost nothing.. 146 */ 147 static struct inode_operations proc_root_inode_operations = { 148 .lookup = proc_root_lookup, 149 .getattr = proc_root_getattr, 150 }; 151 152 /* 153 * This is the root "inode" in the /proc tree.. 154 */ 155 struct proc_dir_entry proc_root = { 156 .low_ino = PROC_ROOT_INO, 157 .namelen = 5, 158 .name = "/proc", 159 .mode = S_IFDIR | S_IRUGO | S_IXUGO, 160 .nlink = 2, 161 .proc_iops = &proc_root_inode_operations, 162 .proc_fops = &proc_root_operations, 163 .parent = &proc_root, 164 }; 165 166 EXPORT_SYMBOL(proc_symlink); 167 EXPORT_SYMBOL(proc_mkdir); 168 EXPORT_SYMBOL(create_proc_entry); 169 EXPORT_SYMBOL(remove_proc_entry); 170 EXPORT_SYMBOL(proc_root); 171 EXPORT_SYMBOL(proc_root_fs); 172 EXPORT_SYMBOL(proc_net); 173 EXPORT_SYMBOL(proc_net_stat); 174 EXPORT_SYMBOL(proc_bus); 175 EXPORT_SYMBOL(proc_root_driver); 176