summaryrefslogtreecommitdiffstats
path: root/fs/proc/root.c
blob: 6ae222b509cee4845ea9afb0764ecfb7b04cae1f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
/*
 *  linux/fs/proc/root.c
 *
 *  Copyright (C) 1991, 1992 Linus Torvalds
 *
 *  proc root directory handling functions
 */

#include <asm/uaccess.h>

#include <linux/errno.h>
#include <linux/time.h>
#include <linux/proc_fs.h>
#include <linux/stat.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/module.h>
#include <linux/bitops.h>
#include <linux/smp_lock.h>
#include <linux/mount.h>

#include "internal.h"

struct proc_dir_entry *proc_net, *proc_net_stat, *proc_bus, *proc_root_fs, *proc_root_driver;

#ifdef CONFIG_SYSCTL
struct proc_dir_entry *proc_sys_root;
#endif

static int proc_get_sb(struct file_system_type *fs_type,
	int flags, const char *dev_name, void *data, struct vfsmount *mnt)
{
	if (proc_mnt) {
		/* Seed the root directory with a pid so it doesn't need
		 * to be special in base.c.  I would do this earlier but
		 * the only task alive when /proc is mounted the first time
		 * is the init_task and it doesn't have any pids.
		 */
		struct proc_inode *ei;
		ei = PROC_I(proc_mnt->mnt_sb->s_root->d_inode);
		if (!ei->pid)
			ei->pid = find_get_pid(1);
	}
	return get_sb_single(fs_type, flags, data, proc_fill_super, mnt);
}

static struct file_system_type proc_fs_type = {
	.name		= "proc",
	.get_sb		= proc_get_sb,
	.kill_sb	= kill_anon_super,
};

void __init proc_root_init(void)
{
	int err = proc_init_inodecache();
	if (err)
		return;
	err = register_filesystem(&proc_fs_type);
	if (err)
		return;
	proc_mnt = kern_mount(&proc_fs_type);
	err = PTR_ERR(proc_mnt);
	if (IS_ERR(proc_mnt)) {
		unregister_filesystem(&proc_fs_type);
		return;
	}
	proc_misc_init();
	proc_net = proc_mkdir("net", NULL);
	proc_net_stat = proc_mkdir("net/stat", NULL);

#ifdef CONFIG_SYSVIPC
	proc_mkdir("sysvipc", NULL);
#endif
#ifdef CONFIG_SYSCTL
	proc_sys_root = proc_mkdir("sys", NULL);
#endif
	proc_root_fs = proc_mkdir("fs", NULL);
	proc_root_driver = proc_mkdir("driver", NULL);
	proc_mkdir("fs/nfsd", NULL); /* somewhere for the nfsd filesystem to be mounted */
#if defined(CONFIG_SUN_OPENPROMFS) || defined(CONFIG_SUN_OPENPROMFS_MODULE)
	/* just give it a mountpoint */
	proc_mkdir("openprom", NULL);
#endif
	proc_tty_init();
#ifdef CONFIG_PROC_DEVICETREE
	proc_device_tree_init();
#endif
	proc_bus = proc_mkdir("bus", NULL);
}

static int proc_root_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat
)
{
	generic_fillattr(dentry->d_inode, stat);
	stat->nlink = proc_root.nlink + nr_processes();
	return 0;
}

static struct dentry *proc_root_lookup(struct inode * dir, struct dentry * dentry, struct nameidata *nd)
{
	if (!proc_lookup(dir, dentry, nd)) {
		return NULL;
	}
	
	return proc_pid_lookup(dir, dentry, nd);
}

static int proc_root_readdir(struct file * filp,
	void * dirent, filldir_t filldir)
{
	unsigned int nr = filp->f_pos;
	int ret;

	lock_kernel();

	if (nr < FIRST_PROCESS_ENTRY) {
		int error = proc_readdir(filp, dirent, filldir);
		if (error <= 0) {
			unlock_kernel();
			return error;
		}
		filp->f_pos = FIRST_PROCESS_ENTRY;
	}
	unlock_kernel();

	ret = proc_pid_readdir(filp, dirent, filldir);
	return ret;
}

/*
 * The root /proc directory is special, as it has the
 * <pid> directories. Thus we don't use the generic
 * directory handling functions for that..
 */
static const struct file_operations proc_root_operations = {
	.read		 = generic_read_dir,
	.readdir	 = proc_root_readdir,
};

/*
 * proc root can do almost nothing..
 */
static const struct inode_operations proc_root_inode_operations = {
	.lookup		= proc_root_lookup,
	.getattr	= proc_root_getattr,
};

/*
 * This is the root "inode" in the /proc tree..
 */
struct proc_dir_entry proc_root = {
	.low_ino	= PROC_ROOT_INO, 
	.namelen	= 5, 
	.name		= "/proc",
	.mode		= S_IFDIR | S_IRUGO | S_IXUGO, 
	.nlink		= 2, 
	.proc_iops	= &proc_root_inode_operations, 
	.proc_fops	= &proc_root_operations,
	.parent		= &proc_root,
};

EXPORT_SYMBOL(proc_symlink);
EXPORT_SYMBOL(proc_mkdir);
EXPORT_SYMBOL(create_proc_entry);
EXPORT_SYMBOL(remove_proc_entry);
EXPORT_SYMBOL(proc_root);
EXPORT_SYMBOL(proc_root_fs);
EXPORT_SYMBOL(proc_net);
EXPORT_SYMBOL(proc_net_stat);
EXPORT_SYMBOL(proc_bus);
EXPORT_SYMBOL(proc_root_driver);