[linux-2.6-block.git] / fs / proc / inode.c

/*
 *  linux/fs/proc/inode.c
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 */

#include <linux/time.h>
#include <linux/proc_fs.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/stat.h>
#include <linux/completion.h>
#include <linux/poll.h>
#include <linux/file.h>
#include <linux/limits.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/smp_lock.h>

#include <asm/system.h>
#include <asm/uaccess.h>

#include "internal.h"

struct proc_dir_entry *de_get(struct proc_dir_entry *de)
{
	if (de)
		atomic_inc(&de->count);
	return de;
}

/*
 * Decrements the use count and checks for deferred deletion.
 */
void de_put(struct proc_dir_entry *de)
{
	if (de) {	
		lock_kernel();		
		if (!atomic_read(&de->count)) {
			printk("de_put: entry %s already free!\n", de->name);
			unlock_kernel();
			return;
		}

		if (atomic_dec_and_test(&de->count))
			free_proc_entry(de);
		unlock_kernel();
	}
}

/*
 * Decrement the use count of the proc_dir_entry.
 */
static void proc_delete_inode(struct inode *inode)
{
	struct proc_dir_entry *de;

	truncate_inode_pages(&inode->i_data, 0);

	/* Stop tracking associated processes */
	put_pid(PROC_I(inode)->pid);

	/* Let go of any associated proc directory entry */
	de = PROC_I(inode)->pde;
	if (de) {
		if (de->owner)
			module_put(de->owner);
		de_put(de);
	}
	clear_inode(inode);
}

struct vfsmount *proc_mnt;

static void proc_read_inode(struct inode * inode)
{
	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
}

static struct kmem_cache * proc_inode_cachep;

static struct inode *proc_alloc_inode(struct super_block *sb)
{
	struct proc_inode *ei;
	struct inode *inode;

	ei = (struct proc_inode *)kmem_cache_alloc(proc_inode_cachep, GFP_KERNEL);
	if (!ei)
		return NULL;
	ei->pid = NULL;
	ei->fd = 0;
	ei->op.proc_get_link = NULL;
	ei->pde = NULL;
	inode = &ei->vfs_inode;
	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
	return inode;
}

static void proc_destroy_inode(struct inode *inode)
{
	kmem_cache_free(proc_inode_cachep, PROC_I(inode));
}

static void init_once(struct kmem_cache * cachep, void *foo)
{
	struct proc_inode *ei = (struct proc_inode *) foo;

	inode_init_once(&ei->vfs_inode);
}

int __init proc_init_inodecache(void)
{
	proc_inode_cachep = kmem_cache_create("proc_inode_cache",
					     sizeof(struct proc_inode),
					     0, (SLAB_RECLAIM_ACCOUNT|
						SLAB_MEM_SPREAD|SLAB_PANIC),
					     init_once);
	return 0;
}

static int proc_remount(struct super_block *sb, int *flags, char *data)
{
	*flags |= MS_NODIRATIME;
	return 0;
}

static const struct super_operations proc_sops = {
	.alloc_inode	= proc_alloc_inode,
	.destroy_inode	= proc_destroy_inode,
	.read_inode	= proc_read_inode,
	.drop_inode	= generic_delete_inode,
	.delete_inode	= proc_delete_inode,
	.statfs		= simple_statfs,
	.remount_fs	= proc_remount,
};

static void pde_users_dec(struct proc_dir_entry *pde)
{
	spin_lock(&pde->pde_unload_lock);
	pde->pde_users--;
	if (pde->pde_unload_completion && pde->pde_users == 0)
		complete(pde->pde_unload_completion);
	spin_unlock(&pde->pde_unload_lock);
}

static loff_t proc_reg_llseek(struct file *file, loff_t offset, int whence)
{
	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
	loff_t rv = -EINVAL;
	loff_t (*llseek)(struct file *, loff_t, int);

	spin_lock(&pde->pde_unload_lock);
	/*
	 * remove_proc_entry() is going to delete PDE (as part of module
	 * cleanup sequence). No new callers into module allowed.
	 */
	if (!pde->proc_fops) {
		spin_unlock(&pde->pde_unload_lock);
		return rv;
	}
	/*
	 * Bump refcount so that remove_proc_entry will wail for ->llseek to
	 * complete.
	 */
	pde->pde_users++;
	/*
	 * Save function pointer under lock, to protect against ->proc_fops
	 * NULL'ifying right after ->pde_unload_lock is dropped.
	 */
	llseek = pde->proc_fops->llseek;
	spin_unlock(&pde->pde_unload_lock);

	if (!llseek)
		llseek = default_llseek;
	rv = llseek(file, offset, whence);

	pde_users_dec(pde);
	return rv;
}

static ssize_t proc_reg_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
{
	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
	ssize_t rv = -EIO;
	ssize_t (*read)(struct file *, char __user *, size_t, loff_t *);

	spin_lock(&pde->pde_unload_lock);
	if (!pde->proc_fops) {
		spin_unlock(&pde->pde_unload_lock);
		return rv;
	}
	pde->pde_users++;
	read = pde->proc_fops->read;
	spin_unlock(&pde->pde_unload_lock);

	if (read)
		rv = read(file, buf, count, ppos);

	pde_users_dec(pde);
	return rv;
}

static ssize_t proc_reg_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
{
	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
	ssize_t rv = -EIO;
	ssize_t (*write)(struct file *, const char __user *, size_t, loff_t *);

	spin_lock(&pde->pde_unload_lock);
	if (!pde->proc_fops) {
		spin_unlock(&pde->pde_unload_lock);
		return rv;
	}
	pde->pde_users++;
	write = pde->proc_fops->write;
	spin_unlock(&pde->pde_unload_lock);

	if (write)
		rv = write(file, buf, count, ppos);

	pde_users_dec(pde);
	return rv;
}

static unsigned int proc_reg_poll(struct file *file, struct poll_table_struct *pts)
{
	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
	unsigned int rv = DEFAULT_POLLMASK;
	unsigned int (*poll)(struct file *, struct poll_table_struct *);

	spin_lock(&pde->pde_unload_lock);
	if (!pde->proc_fops) {
		spin_unlock(&pde->pde_unload_lock);
		return rv;
	}
	pde->pde_users++;
	poll = pde->proc_fops->poll;
	spin_unlock(&pde->pde_unload_lock);

	if (poll)
		rv = poll(file, pts);

	pde_users_dec(pde);
	return rv;
}

static long proc_reg_unlocked_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
	long rv = -ENOTTY;
	long (*unlocked_ioctl)(struct file *, unsigned int, unsigned long);
	int (*ioctl)(struct inode *, struct file *, unsigned int, unsigned long);

	spin_lock(&pde->pde_unload_lock);
	if (!pde->proc_fops) {
		spin_unlock(&pde->pde_unload_lock);
		return rv;
	}
	pde->pde_users++;
	unlocked_ioctl = pde->proc_fops->unlocked_ioctl;
	ioctl = pde->proc_fops->ioctl;
	spin_unlock(&pde->pde_unload_lock);

	if (unlocked_ioctl) {
		rv = unlocked_ioctl(file, cmd, arg);
		if (rv == -ENOIOCTLCMD)
			rv = -EINVAL;
	} else if (ioctl) {
		lock_kernel();
		rv = ioctl(file->f_path.dentry->d_inode, file, cmd, arg);
		unlock_kernel();
	}

	pde_users_dec(pde);
	return rv;
}

#ifdef CONFIG_COMPAT
static long proc_reg_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
	long rv = -ENOTTY;
	long (*compat_ioctl)(struct file *, unsigned int, unsigned long);

	spin_lock(&pde->pde_unload_lock);
	if (!pde->proc_fops) {
		spin_unlock(&pde->pde_unload_lock);
		return rv;
	}
	pde->pde_users++;
	compat_ioctl = pde->proc_fops->compat_ioctl;
	spin_unlock(&pde->pde_unload_lock);

	if (compat_ioctl)
		rv = compat_ioctl(file, cmd, arg);

	pde_users_dec(pde);
	return rv;
}
#endif

static int proc_reg_mmap(struct file *file, struct vm_area_struct *vma)
{
	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
	int rv = -EIO;
	int (*mmap)(struct file *, struct vm_area_struct *);

	spin_lock(&pde->pde_unload_lock);
	if (!pde->proc_fops) {
		spin_unlock(&pde->pde_unload_lock);
		return rv;
	}
	pde->pde_users++;
	mmap = pde->proc_fops->mmap;
	spin_unlock(&pde->pde_unload_lock);

	if (mmap)
		rv = mmap(file, vma);

	pde_users_dec(pde);
	return rv;
}

static int proc_reg_open(struct inode *inode, struct file *file)
{
	struct proc_dir_entry *pde = PDE(inode);
	int rv = 0;
	int (*open)(struct inode *, struct file *);

	spin_lock(&pde->pde_unload_lock);
	if (!pde->proc_fops) {
		spin_unlock(&pde->pde_unload_lock);
		return rv;
	}
	pde->pde_users++;
	open = pde->proc_fops->open;
	spin_unlock(&pde->pde_unload_lock);

	if (open)
		rv = open(inode, file);

	pde_users_dec(pde);
	return rv;
}

static int proc_reg_release(struct inode *inode, struct file *file)
{
	struct proc_dir_entry *pde = PDE(inode);
	int rv = 0;
	int (*release)(struct inode *, struct file *);

	spin_lock(&pde->pde_unload_lock);
	if (!pde->proc_fops) {
		spin_unlock(&pde->pde_unload_lock);
		return rv;
	}
	pde->pde_users++;
	release = pde->proc_fops->release;
	spin_unlock(&pde->pde_unload_lock);

	if (release)
		rv = release(inode, file);

	pde_users_dec(pde);
	return rv;
}

static const struct file_operations proc_reg_file_ops = {
	.llseek		= proc_reg_llseek,
	.read		= proc_reg_read,
	.write		= proc_reg_write,
	.poll		= proc_reg_poll,
	.unlocked_ioctl	= proc_reg_unlocked_ioctl,
#ifdef CONFIG_COMPAT
	.compat_ioctl	= proc_reg_compat_ioctl,
#endif
	.mmap		= proc_reg_mmap,
	.open		= proc_reg_open,
	.release	= proc_reg_release,
};

#ifdef CONFIG_COMPAT
static const struct file_operations proc_reg_file_ops_no_compat = {
	.llseek		= proc_reg_llseek,
	.read		= proc_reg_read,
	.write		= proc_reg_write,
	.poll		= proc_reg_poll,
	.unlocked_ioctl	= proc_reg_unlocked_ioctl,
	.mmap		= proc_reg_mmap,
	.open		= proc_reg_open,
	.release	= proc_reg_release,
};
#endif

struct inode *proc_get_inode(struct super_block *sb, unsigned int ino,
				struct proc_dir_entry *de)
{
	struct inode * inode;

	if (de != NULL && !try_module_get(de->owner))
		goto out_mod;

	inode = iget(sb, ino);
	if (!inode)
		goto out_ino;

	PROC_I(inode)->fd = 0;
	PROC_I(inode)->pde = de;
	if (de) {
		if (de->mode) {
			inode->i_mode = de->mode;
			inode->i_uid = de->uid;
			inode->i_gid = de->gid;
		}
		if (de->size)
			inode->i_size = de->size;
		if (de->nlink)
			inode->i_nlink = de->nlink;
		if (de->proc_iops)
			inode->i_op = de->proc_iops;
		if (de->proc_fops) {
			if (S_ISREG(inode->i_mode)) {
#ifdef CONFIG_COMPAT
				if (!de->proc_fops->compat_ioctl)
					inode->i_fop =
						&proc_reg_file_ops_no_compat;
				else
#endif
					inode->i_fop = &proc_reg_file_ops;
			}
			else
				inode->i_fop = de->proc_fops;
		}
	}

	return inode;

out_ino:
	if (de != NULL)
		module_put(de->owner);
out_mod:
	return NULL;
}			

int proc_fill_super(struct super_block *s)
{
	struct inode * root_inode;

	s->s_flags |= MS_NODIRATIME | MS_NOSUID | MS_NOEXEC;
	s->s_blocksize = 1024;
	s->s_blocksize_bits = 10;
	s->s_magic = PROC_SUPER_MAGIC;
	s->s_op = &proc_sops;
	s->s_time_gran = 1;
	
	de_get(&proc_root);
	root_inode = proc_get_inode(s, PROC_ROOT_INO, &proc_root);
	if (!root_inode)
		goto out_no_root;
	root_inode->i_uid = 0;
	root_inode->i_gid = 0;
	s->s_root = d_alloc_root(root_inode);
	if (!s->s_root)
		goto out_no_root;
	return 0;

out_no_root:
	printk("proc_read_super: get root inode failed\n");
	iput(root_inode);
	de_put(&proc_root);
	return -ENOMEM;
}
MODULE_LICENSE("GPL");
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/fs/proc/inode.c
	3	*
	4	* Copyright (C) 1991, 1992 Linus Torvalds
	5	*/
	6
	7	#include <linux/time.h>
	8	#include <linux/proc_fs.h>
	9	#include <linux/kernel.h>
	10	#include <linux/mm.h>
	11	#include <linux/string.h>
	12	#include <linux/stat.h>
786d7e16	13	#include <linux/completion.h>
dd23aae4	14	#include <linux/poll.h>
1da177e4 LT	15	#include <linux/file.h>
	16	#include <linux/limits.h>
	17	#include <linux/init.h>
	18	#include <linux/module.h>
	19	#include <linux/smp_lock.h>
	20
	21	#include <asm/system.h>
	22	#include <asm/uaccess.h>
	23
fee781e6	24	#include "internal.h"
1da177e4	25
7695650a	26	struct proc_dir_entry de_get(struct proc_dir_entry de)
1da177e4 LT	27	{
	28	if (de)
	29	atomic_inc(&de->count);
	30	return de;
	31	}
	32
	33	/*
	34	* Decrements the use count and checks for deferred deletion.
	35	*/
7695650a	36	void de_put(struct proc_dir_entry *de)
1da177e4 LT	37	{
	38	if (de) {
	39	lock_kernel();
	40	if (!atomic_read(&de->count)) {
	41	printk("de_put: entry %s already free!\n", de->name);
	42	unlock_kernel();
	43	return;
	44	}
	45
5a622f2d AD	46	if (atomic_dec_and_test(&de->count))
5a622f2d AD	47	free_proc_entry(de);
1da177e4 LT	48	unlock_kernel();
	49	}
	50	}
	51
	52	/*
	53	* Decrement the use count of the proc_dir_entry.
	54	*/
	55	static void proc_delete_inode(struct inode *inode)
	56	{
	57	struct proc_dir_entry *de;
1da177e4	58
fef26658 MF	59	truncate_inode_pages(&inode->i_data, 0);
fef26658 MF	60
99f89551	61	/* Stop tracking associated processes */
13b41b09	62	put_pid(PROC_I(inode)->pid);
1da177e4 LT	63
	64	/* Let go of any associated proc directory entry */
	65	de = PROC_I(inode)->pde;
	66	if (de) {
	67	if (de->owner)
	68	module_put(de->owner);
	69	de_put(de);
	70	}
	71	clear_inode(inode);
	72	}
	73
	74	struct vfsmount *proc_mnt;
	75
	76	static void proc_read_inode(struct inode * inode)
	77	{
	78	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
	79	}
	80
e18b890b	81	static struct kmem_cache * proc_inode_cachep;
1da177e4 LT	82
	83	static struct inode proc_alloc_inode(struct super_block sb)
	84	{
	85	struct proc_inode *ei;
	86	struct inode *inode;
	87
e94b1766	88	ei = (struct proc_inode *)kmem_cache_alloc(proc_inode_cachep, GFP_KERNEL);
1da177e4 LT	89	if (!ei)
1da177e4 LT	90	return NULL;
13b41b09	91	ei->pid = NULL;
aed7a6c4	92	ei->fd = 0;
1da177e4 LT	93	ei->op.proc_get_link = NULL;
	94	ei->pde = NULL;
	95	inode = &ei->vfs_inode;
	96	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
	97	return inode;
	98	}
	99
	100	static void proc_destroy_inode(struct inode *inode)
	101	{
	102	kmem_cache_free(proc_inode_cachep, PROC_I(inode));
	103	}
	104
4ba9b9d0	105	static void init_once(struct kmem_cache * cachep, void *foo)
1da177e4 LT	106	{
	107	struct proc_inode ei = (struct proc_inode ) foo;
	108
a35afb83	109	inode_init_once(&ei->vfs_inode);
1da177e4	110	}
20c2df83	111
1da177e4 LT	112	int __init proc_init_inodecache(void)
	113	{
	114	proc_inode_cachep = kmem_cache_create("proc_inode_cache",
	115	sizeof(struct proc_inode),
fffb60f9	116	0, (SLAB_RECLAIM_ACCOUNT\|
040b5c6f	117	SLAB_MEM_SPREAD\|SLAB_PANIC),
20c2df83	118	init_once);
1da177e4 LT	119	return 0;
	120	}
	121
	122	static int proc_remount(struct super_block sb, int flags, char *data)
	123	{
	124	*flags \|= MS_NODIRATIME;
	125	return 0;
	126	}
	127
ee9b6d61	128	static const struct super_operations proc_sops = {
1da177e4 LT	129	.alloc_inode = proc_alloc_inode,
	130	.destroy_inode = proc_destroy_inode,
	131	.read_inode = proc_read_inode,
	132	.drop_inode = generic_delete_inode,
	133	.delete_inode = proc_delete_inode,
	134	.statfs = simple_statfs,
	135	.remount_fs = proc_remount,
	136	};
	137
786d7e16 AD	138	static void pde_users_dec(struct proc_dir_entry *pde)
	139	{
	140	spin_lock(&pde->pde_unload_lock);
	141	pde->pde_users--;
	142	if (pde->pde_unload_completion && pde->pde_users == 0)
	143	complete(pde->pde_unload_completion);
	144	spin_unlock(&pde->pde_unload_lock);
	145	}
	146
	147	static loff_t proc_reg_llseek(struct file *file, loff_t offset, int whence)
	148	{
	149	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
	150	loff_t rv = -EINVAL;
	151	loff_t (llseek)(struct file , loff_t, int);
	152
	153	spin_lock(&pde->pde_unload_lock);
	154	/*
	155	* remove_proc_entry() is going to delete PDE (as part of module
	156	* cleanup sequence). No new callers into module allowed.
	157	*/
	158	if (!pde->proc_fops) {
	159	spin_unlock(&pde->pde_unload_lock);
	160	return rv;
	161	}
	162	/*
	163	* Bump refcount so that remove_proc_entry will wail for ->llseek to
	164	* complete.
	165	*/
	166	pde->pde_users++;
	167	/*
	168	* Save function pointer under lock, to protect against ->proc_fops
	169	* NULL'ifying right after ->pde_unload_lock is dropped.
	170	*/
	171	llseek = pde->proc_fops->llseek;
	172	spin_unlock(&pde->pde_unload_lock);
	173
	174	if (!llseek)
	175	llseek = default_llseek;
	176	rv = llseek(file, offset, whence);
	177
	178	pde_users_dec(pde);
	179	return rv;
	180	}
	181
	182	static ssize_t proc_reg_read(struct file file, char __user buf, size_t count, loff_t *ppos)
	183	{
	184	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
	185	ssize_t rv = -EIO;
	186	ssize_t (read)(struct file , char __user , size_t, loff_t );
	187
	188	spin_lock(&pde->pde_unload_lock);
	189	if (!pde->proc_fops) {
	190	spin_unlock(&pde->pde_unload_lock);
	191	return rv;
	192	}
	193	pde->pde_users++;
	194	read = pde->proc_fops->read;
	195	spin_unlock(&pde->pde_unload_lock);
	196
	197	if (read)
	198	rv = read(file, buf, count, ppos);
	199
	200	pde_users_dec(pde);
	201	return rv;
202	}
203
204	static ssize_t proc_reg_write(struct file file, const char __user buf, size_t count, loff_t *ppos)
205	{
206	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
207	ssize_t rv = -EIO;
208	ssize_t (write)(struct file , const char __user , size_t, loff_t );
209
210	spin_lock(&pde->pde_unload_lock);
211	if (!pde->proc_fops) {
212	spin_unlock(&pde->pde_unload_lock);
213	return rv;
214	}
215	pde->pde_users++;
216	write = pde->proc_fops->write;
217	spin_unlock(&pde->pde_unload_lock);
218
219	if (write)
220	rv = write(file, buf, count, ppos);
221
222	pde_users_dec(pde);
223	return rv;
224	}
225
226	static unsigned int proc_reg_poll(struct file file, struct poll_table_struct pts)
227	{
228	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
dd23aae4	229	unsigned int rv = DEFAULT_POLLMASK;
786d7e16 AD	230	unsigned int (poll)(struct file , struct poll_table_struct *);
	231
	232	spin_lock(&pde->pde_unload_lock);
	233	if (!pde->proc_fops) {
	234	spin_unlock(&pde->pde_unload_lock);
	235	return rv;
	236	}
	237	pde->pde_users++;
	238	poll = pde->proc_fops->poll;
	239	spin_unlock(&pde->pde_unload_lock);
	240
	241	if (poll)
	242	rv = poll(file, pts);
	243
	244	pde_users_dec(pde);
	245	return rv;
	246	}
	247
	248	static long proc_reg_unlocked_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
	249	{
	250	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
	251	long rv = -ENOTTY;
	252	long (unlocked_ioctl)(struct file , unsigned int, unsigned long);
	253	int (ioctl)(struct inode , struct file *, unsigned int, unsigned long);
	254
	255	spin_lock(&pde->pde_unload_lock);
	256	if (!pde->proc_fops) {
	257	spin_unlock(&pde->pde_unload_lock);
	258	return rv;
	259	}
	260	pde->pde_users++;
	261	unlocked_ioctl = pde->proc_fops->unlocked_ioctl;
	262	ioctl = pde->proc_fops->ioctl;
	263	spin_unlock(&pde->pde_unload_lock);
	264
	265	if (unlocked_ioctl) {
	266	rv = unlocked_ioctl(file, cmd, arg);
	267	if (rv == -ENOIOCTLCMD)
	268	rv = -EINVAL;
	269	} else if (ioctl) {
	270	lock_kernel();
	271	rv = ioctl(file->f_path.dentry->d_inode, file, cmd, arg);
	272	unlock_kernel();
	273	}
	274
	275	pde_users_dec(pde);
	276	return rv;
	277	}
	278
	279	#ifdef CONFIG_COMPAT
	280	static long proc_reg_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
	281	{
	282	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
	283	long rv = -ENOTTY;
	284	long (compat_ioctl)(struct file , unsigned int, unsigned long);
	285
	286	spin_lock(&pde->pde_unload_lock);
	287	if (!pde->proc_fops) {
	288	spin_unlock(&pde->pde_unload_lock);
	289	return rv;
	290	}
	291	pde->pde_users++;
	292	compat_ioctl = pde->proc_fops->compat_ioctl;
	293	spin_unlock(&pde->pde_unload_lock);
294
295	if (compat_ioctl)
296	rv = compat_ioctl(file, cmd, arg);
297
298	pde_users_dec(pde);
299	return rv;
300	}
301	#endif
302
303	static int proc_reg_mmap(struct file file, struct vm_area_struct vma)
304	{
305	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
306	int rv = -EIO;
307	int (mmap)(struct file , struct vm_area_struct *);
308
309	spin_lock(&pde->pde_unload_lock);
310	if (!pde->proc_fops) {
311	spin_unlock(&pde->pde_unload_lock);
312	return rv;
313	}
314	pde->pde_users++;
315	mmap = pde->proc_fops->mmap;
316	spin_unlock(&pde->pde_unload_lock);
317
318	if (mmap)
319	rv = mmap(file, vma);
320
321	pde_users_dec(pde);
322	return rv;
323	}
324
325	static int proc_reg_open(struct inode inode, struct file file)
326	{
327	struct proc_dir_entry *pde = PDE(inode);
328	int rv = 0;
329	int (open)(struct inode , struct file *);
330
331	spin_lock(&pde->pde_unload_lock);
332	if (!pde->proc_fops) {
333	spin_unlock(&pde->pde_unload_lock);
334	return rv;
335	}
336	pde->pde_users++;
337	open = pde->proc_fops->open;
338	spin_unlock(&pde->pde_unload_lock);
339
340	if (open)
341	rv = open(inode, file);
342
343	pde_users_dec(pde);
344	return rv;
345	}
346
347	static int proc_reg_release(struct inode inode, struct file file)
348	{
349	struct proc_dir_entry *pde = PDE(inode);
350	int rv = 0;
351	int (release)(struct inode , struct file *);
352
353	spin_lock(&pde->pde_unload_lock);
354	if (!pde->proc_fops) {
355	spin_unlock(&pde->pde_unload_lock);
356	return rv;
357	}
358	pde->pde_users++;
359	release = pde->proc_fops->release;
360	spin_unlock(&pde->pde_unload_lock);
361
362	if (release)
363	rv = release(inode, file);
364
365	pde_users_dec(pde);
366	return rv;
367	}
368
369	static const struct file_operations proc_reg_file_ops = {
370	.llseek = proc_reg_llseek,
371	.read = proc_reg_read,
372	.write = proc_reg_write,
373	.poll = proc_reg_poll,
374	.unlocked_ioctl = proc_reg_unlocked_ioctl,
375	#ifdef CONFIG_COMPAT
376	.compat_ioctl = proc_reg_compat_ioctl,
377	#endif
378	.mmap = proc_reg_mmap,
379	.open = proc_reg_open,
380	.release = proc_reg_release,
381	};
382
778f3dd5 DM	383	#ifdef CONFIG_COMPAT
	384	static const struct file_operations proc_reg_file_ops_no_compat = {
	385	.llseek = proc_reg_llseek,
	386	.read = proc_reg_read,
	387	.write = proc_reg_write,
	388	.poll = proc_reg_poll,
	389	.unlocked_ioctl = proc_reg_unlocked_ioctl,
	390	.mmap = proc_reg_mmap,
	391	.open = proc_reg_open,
	392	.release = proc_reg_release,
	393	};
	394	#endif
	395
1da177e4 LT	396	struct inode proc_get_inode(struct super_block sb, unsigned int ino,
	397	struct proc_dir_entry *de)
	398	{
	399	struct inode * inode;
	400
e9543659 KK	401	if (de != NULL && !try_module_get(de->owner))
	402	goto out_mod;
	403
1da177e4 LT	404	inode = iget(sb, ino);
1da177e4 LT	405	if (!inode)
e9543659 KK	406	goto out_ino;
e9543659 KK	407
77b14db5	408	PROC_I(inode)->fd = 0;
1da177e4 LT	409	PROC_I(inode)->pde = de;
	410	if (de) {
	411	if (de->mode) {
	412	inode->i_mode = de->mode;
	413	inode->i_uid = de->uid;
	414	inode->i_gid = de->gid;
	415	}
	416	if (de->size)
	417	inode->i_size = de->size;
	418	if (de->nlink)
	419	inode->i_nlink = de->nlink;
1da177e4 LT	420	if (de->proc_iops)
1da177e4 LT	421	inode->i_op = de->proc_iops;
786d7e16	422	if (de->proc_fops) {
778f3dd5 DM	423	if (S_ISREG(inode->i_mode)) {
	424	#ifdef CONFIG_COMPAT
	425	if (!de->proc_fops->compat_ioctl)
	426	inode->i_fop =
	427	&proc_reg_file_ops_no_compat;
	428	else
	429	#endif
	430	inode->i_fop = &proc_reg_file_ops;
	431	}
786d7e16 AD	432	else
	433	inode->i_fop = de->proc_fops;
	434	}
1da177e4 LT	435	}
1da177e4 LT	436
1da177e4 LT	437	return inode;
1da177e4 LT	438
e9543659 KK	439	out_ino:
	440	if (de != NULL)
	441	module_put(de->owner);
	442	out_mod:
e9543659	443	return NULL;
1da177e4 LT	444	}
1da177e4 LT	445
07543f5c	446	int proc_fill_super(struct super_block *s)
1da177e4 LT	447	{
	448	struct inode * root_inode;
	449
92d03285	450	s->s_flags \|= MS_NODIRATIME \| MS_NOSUID \| MS_NOEXEC;
1da177e4 LT	451	s->s_blocksize = 1024;
	452	s->s_blocksize_bits = 10;
	453	s->s_magic = PROC_SUPER_MAGIC;
	454	s->s_op = &proc_sops;
	455	s->s_time_gran = 1;
	456
7695650a	457	de_get(&proc_root);
1da177e4 LT	458	root_inode = proc_get_inode(s, PROC_ROOT_INO, &proc_root);
	459	if (!root_inode)
	460	goto out_no_root;
1da177e4 LT	461	root_inode->i_uid = 0;
	462	root_inode->i_gid = 0;
	463	s->s_root = d_alloc_root(root_inode);
	464	if (!s->s_root)
	465	goto out_no_root;
	466	return 0;
	467
	468	out_no_root:
	469	printk("proc_read_super: get root inode failed\n");
	470	iput(root_inode);
7695650a	471	de_put(&proc_root);
1da177e4 LT	472	return -ENOMEM;
	473	}
	474	MODULE_LICENSE("GPL");