[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)) {
			if (de->deleted) {
				printk("de_put: deferred delete of %s\n",
					de->name);
				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, void *data, int silent)
{
	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
	46	if (atomic_dec_and_test(&de->count)) {
	47	if (de->deleted) {
	48	printk("de_put: deferred delete of %s\n",
	49	de->name);
	50	free_proc_entry(de);
	51	}
	52	}
	53	unlock_kernel();
	54	}
	55	}
	56
	57	/*
	58	* Decrement the use count of the proc_dir_entry.
	59	*/
	60	static void proc_delete_inode(struct inode *inode)
	61	{
	62	struct proc_dir_entry *de;
1da177e4	63
fef26658 MF	64	truncate_inode_pages(&inode->i_data, 0);
fef26658 MF	65
99f89551	66	/* Stop tracking associated processes */
13b41b09	67	put_pid(PROC_I(inode)->pid);
1da177e4 LT	68
	69	/* Let go of any associated proc directory entry */
	70	de = PROC_I(inode)->pde;
	71	if (de) {
	72	if (de->owner)
	73	module_put(de->owner);
	74	de_put(de);
	75	}
	76	clear_inode(inode);
	77	}
	78
	79	struct vfsmount *proc_mnt;
	80
	81	static void proc_read_inode(struct inode * inode)
	82	{
	83	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
	84	}
	85
e18b890b	86	static struct kmem_cache * proc_inode_cachep;
1da177e4 LT	87
	88	static struct inode proc_alloc_inode(struct super_block sb)
	89	{
	90	struct proc_inode *ei;
	91	struct inode *inode;
	92
e94b1766	93	ei = (struct proc_inode *)kmem_cache_alloc(proc_inode_cachep, GFP_KERNEL);
1da177e4 LT	94	if (!ei)
1da177e4 LT	95	return NULL;
13b41b09	96	ei->pid = NULL;
aed7a6c4	97	ei->fd = 0;
1da177e4 LT	98	ei->op.proc_get_link = NULL;
	99	ei->pde = NULL;
	100	inode = &ei->vfs_inode;
	101	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
	102	return inode;
	103	}
	104
	105	static void proc_destroy_inode(struct inode *inode)
	106	{
	107	kmem_cache_free(proc_inode_cachep, PROC_I(inode));
	108	}
	109
4ba9b9d0	110	static void init_once(struct kmem_cache * cachep, void *foo)
1da177e4 LT	111	{
	112	struct proc_inode ei = (struct proc_inode ) foo;
	113
a35afb83	114	inode_init_once(&ei->vfs_inode);
1da177e4	115	}
20c2df83	116
1da177e4 LT	117	int __init proc_init_inodecache(void)
	118	{
	119	proc_inode_cachep = kmem_cache_create("proc_inode_cache",
	120	sizeof(struct proc_inode),
fffb60f9	121	0, (SLAB_RECLAIM_ACCOUNT\|
040b5c6f	122	SLAB_MEM_SPREAD\|SLAB_PANIC),
20c2df83	123	init_once);
1da177e4 LT	124	return 0;
	125	}
	126
	127	static int proc_remount(struct super_block sb, int flags, char *data)
	128	{
	129	*flags \|= MS_NODIRATIME;
	130	return 0;
	131	}
	132
ee9b6d61	133	static const struct super_operations proc_sops = {
1da177e4 LT	134	.alloc_inode = proc_alloc_inode,
	135	.destroy_inode = proc_destroy_inode,
	136	.read_inode = proc_read_inode,
	137	.drop_inode = generic_delete_inode,
	138	.delete_inode = proc_delete_inode,
	139	.statfs = simple_statfs,
	140	.remount_fs = proc_remount,
	141	};
	142
786d7e16 AD	143	static void pde_users_dec(struct proc_dir_entry *pde)
	144	{
	145	spin_lock(&pde->pde_unload_lock);
	146	pde->pde_users--;
	147	if (pde->pde_unload_completion && pde->pde_users == 0)
	148	complete(pde->pde_unload_completion);
	149	spin_unlock(&pde->pde_unload_lock);
	150	}
	151
	152	static loff_t proc_reg_llseek(struct file *file, loff_t offset, int whence)
	153	{
	154	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
	155	loff_t rv = -EINVAL;
	156	loff_t (llseek)(struct file , loff_t, int);
	157
	158	spin_lock(&pde->pde_unload_lock);
	159	/*
	160	* remove_proc_entry() is going to delete PDE (as part of module
	161	* cleanup sequence). No new callers into module allowed.
	162	*/
	163	if (!pde->proc_fops) {
	164	spin_unlock(&pde->pde_unload_lock);
	165	return rv;
	166	}
	167	/*
	168	* Bump refcount so that remove_proc_entry will wail for ->llseek to
	169	* complete.
	170	*/
	171	pde->pde_users++;
	172	/*
	173	* Save function pointer under lock, to protect against ->proc_fops
	174	* NULL'ifying right after ->pde_unload_lock is dropped.
	175	*/
	176	llseek = pde->proc_fops->llseek;
	177	spin_unlock(&pde->pde_unload_lock);
	178
	179	if (!llseek)
	180	llseek = default_llseek;
	181	rv = llseek(file, offset, whence);
	182
	183	pde_users_dec(pde);
	184	return rv;
	185	}
	186
	187	static ssize_t proc_reg_read(struct file file, char __user buf, size_t count, loff_t *ppos)
	188	{
	189	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
	190	ssize_t rv = -EIO;
	191	ssize_t (read)(struct file , char __user , size_t, loff_t );
	192
	193	spin_lock(&pde->pde_unload_lock);
	194	if (!pde->proc_fops) {
	195	spin_unlock(&pde->pde_unload_lock);
	196	return rv;
	197	}
	198	pde->pde_users++;
	199	read = pde->proc_fops->read;
	200	spin_unlock(&pde->pde_unload_lock);
	201
	202	if (read)
	203	rv = read(file, buf, count, ppos);
	204
	205	pde_users_dec(pde);
	206	return rv;
207	}
208
209	static ssize_t proc_reg_write(struct file file, const char __user buf, size_t count, loff_t *ppos)
210	{
211	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
212	ssize_t rv = -EIO;
213	ssize_t (write)(struct file , const char __user , size_t, loff_t );
214
215	spin_lock(&pde->pde_unload_lock);
216	if (!pde->proc_fops) {
217	spin_unlock(&pde->pde_unload_lock);
218	return rv;
219	}
220	pde->pde_users++;
221	write = pde->proc_fops->write;
222	spin_unlock(&pde->pde_unload_lock);
223
224	if (write)
225	rv = write(file, buf, count, ppos);
226
227	pde_users_dec(pde);
228	return rv;
229	}
230
231	static unsigned int proc_reg_poll(struct file file, struct poll_table_struct pts)
232	{
233	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
dd23aae4	234	unsigned int rv = DEFAULT_POLLMASK;
786d7e16 AD	235	unsigned int (poll)(struct file , struct poll_table_struct *);
	236
	237	spin_lock(&pde->pde_unload_lock);
	238	if (!pde->proc_fops) {
	239	spin_unlock(&pde->pde_unload_lock);
	240	return rv;
	241	}
	242	pde->pde_users++;
	243	poll = pde->proc_fops->poll;
	244	spin_unlock(&pde->pde_unload_lock);
	245
	246	if (poll)
	247	rv = poll(file, pts);
	248
	249	pde_users_dec(pde);
	250	return rv;
	251	}
	252
	253	static long proc_reg_unlocked_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
	254	{
	255	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
	256	long rv = -ENOTTY;
	257	long (unlocked_ioctl)(struct file , unsigned int, unsigned long);
	258	int (ioctl)(struct inode , struct file *, unsigned int, unsigned long);
	259
	260	spin_lock(&pde->pde_unload_lock);
	261	if (!pde->proc_fops) {
	262	spin_unlock(&pde->pde_unload_lock);
	263	return rv;
	264	}
	265	pde->pde_users++;
	266	unlocked_ioctl = pde->proc_fops->unlocked_ioctl;
	267	ioctl = pde->proc_fops->ioctl;
	268	spin_unlock(&pde->pde_unload_lock);
	269
	270	if (unlocked_ioctl) {
	271	rv = unlocked_ioctl(file, cmd, arg);
	272	if (rv == -ENOIOCTLCMD)
	273	rv = -EINVAL;
	274	} else if (ioctl) {
	275	lock_kernel();
	276	rv = ioctl(file->f_path.dentry->d_inode, file, cmd, arg);
	277	unlock_kernel();
	278	}
	279
	280	pde_users_dec(pde);
	281	return rv;
	282	}
	283
	284	#ifdef CONFIG_COMPAT
	285	static long proc_reg_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
	286	{
	287	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
	288	long rv = -ENOTTY;
	289	long (compat_ioctl)(struct file , unsigned int, unsigned long);
	290
	291	spin_lock(&pde->pde_unload_lock);
	292	if (!pde->proc_fops) {
	293	spin_unlock(&pde->pde_unload_lock);
	294	return rv;
	295	}
	296	pde->pde_users++;
	297	compat_ioctl = pde->proc_fops->compat_ioctl;
	298	spin_unlock(&pde->pde_unload_lock);
299
300	if (compat_ioctl)
301	rv = compat_ioctl(file, cmd, arg);
302
303	pde_users_dec(pde);
304	return rv;
305	}
306	#endif
307
308	static int proc_reg_mmap(struct file file, struct vm_area_struct vma)
309	{
310	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
311	int rv = -EIO;
312	int (mmap)(struct file , struct vm_area_struct *);
313
314	spin_lock(&pde->pde_unload_lock);
315	if (!pde->proc_fops) {
316	spin_unlock(&pde->pde_unload_lock);
317	return rv;
318	}
319	pde->pde_users++;
320	mmap = pde->proc_fops->mmap;
321	spin_unlock(&pde->pde_unload_lock);
322
323	if (mmap)
324	rv = mmap(file, vma);
325
326	pde_users_dec(pde);
327	return rv;
328	}
329
330	static int proc_reg_open(struct inode inode, struct file file)
331	{
332	struct proc_dir_entry *pde = PDE(inode);
333	int rv = 0;
334	int (open)(struct inode , struct file *);
335
336	spin_lock(&pde->pde_unload_lock);
337	if (!pde->proc_fops) {
338	spin_unlock(&pde->pde_unload_lock);
339	return rv;
340	}
341	pde->pde_users++;
342	open = pde->proc_fops->open;
343	spin_unlock(&pde->pde_unload_lock);
344
345	if (open)
346	rv = open(inode, file);
347
348	pde_users_dec(pde);
349	return rv;
350	}
351
352	static int proc_reg_release(struct inode inode, struct file file)
353	{
354	struct proc_dir_entry *pde = PDE(inode);
355	int rv = 0;
356	int (release)(struct inode , struct file *);
357
358	spin_lock(&pde->pde_unload_lock);
359	if (!pde->proc_fops) {
360	spin_unlock(&pde->pde_unload_lock);
361	return rv;
362	}
363	pde->pde_users++;
364	release = pde->proc_fops->release;
365	spin_unlock(&pde->pde_unload_lock);
366
367	if (release)
368	rv = release(inode, file);
369
370	pde_users_dec(pde);
371	return rv;
372	}
373
374	static const struct file_operations proc_reg_file_ops = {
375	.llseek = proc_reg_llseek,
376	.read = proc_reg_read,
377	.write = proc_reg_write,
378	.poll = proc_reg_poll,
379	.unlocked_ioctl = proc_reg_unlocked_ioctl,
380	#ifdef CONFIG_COMPAT
381	.compat_ioctl = proc_reg_compat_ioctl,
382	#endif
383	.mmap = proc_reg_mmap,
384	.open = proc_reg_open,
385	.release = proc_reg_release,
386	};
387
778f3dd5 DM	388	#ifdef CONFIG_COMPAT
	389	static const struct file_operations proc_reg_file_ops_no_compat = {
	390	.llseek = proc_reg_llseek,
	391	.read = proc_reg_read,
	392	.write = proc_reg_write,
	393	.poll = proc_reg_poll,
	394	.unlocked_ioctl = proc_reg_unlocked_ioctl,
	395	.mmap = proc_reg_mmap,
	396	.open = proc_reg_open,
	397	.release = proc_reg_release,
	398	};
	399	#endif
	400
1da177e4 LT	401	struct inode proc_get_inode(struct super_block sb, unsigned int ino,
	402	struct proc_dir_entry *de)
	403	{
	404	struct inode * inode;
	405
e9543659 KK	406	if (de != NULL && !try_module_get(de->owner))
	407	goto out_mod;
	408
1da177e4 LT	409	inode = iget(sb, ino);
1da177e4 LT	410	if (!inode)
e9543659 KK	411	goto out_ino;
e9543659 KK	412
77b14db5	413	PROC_I(inode)->fd = 0;
1da177e4 LT	414	PROC_I(inode)->pde = de;
	415	if (de) {
	416	if (de->mode) {
	417	inode->i_mode = de->mode;
	418	inode->i_uid = de->uid;
	419	inode->i_gid = de->gid;
	420	}
	421	if (de->size)
	422	inode->i_size = de->size;
	423	if (de->nlink)
	424	inode->i_nlink = de->nlink;
1da177e4 LT	425	if (de->proc_iops)
1da177e4 LT	426	inode->i_op = de->proc_iops;
786d7e16	427	if (de->proc_fops) {
778f3dd5 DM	428	if (S_ISREG(inode->i_mode)) {
	429	#ifdef CONFIG_COMPAT
	430	if (!de->proc_fops->compat_ioctl)
	431	inode->i_fop =
	432	&proc_reg_file_ops_no_compat;
	433	else
	434	#endif
	435	inode->i_fop = &proc_reg_file_ops;
	436	}
786d7e16 AD	437	else
	438	inode->i_fop = de->proc_fops;
	439	}
1da177e4 LT	440	}
1da177e4 LT	441
1da177e4 LT	442	return inode;
1da177e4 LT	443
e9543659 KK	444	out_ino:
	445	if (de != NULL)
	446	module_put(de->owner);
	447	out_mod:
e9543659	448	return NULL;
1da177e4 LT	449	}
	450
	451	int proc_fill_super(struct super_block s, void data, int silent)
	452	{
	453	struct inode * root_inode;
	454
92d03285	455	s->s_flags \|= MS_NODIRATIME \| MS_NOSUID \| MS_NOEXEC;
1da177e4 LT	456	s->s_blocksize = 1024;
	457	s->s_blocksize_bits = 10;
	458	s->s_magic = PROC_SUPER_MAGIC;
	459	s->s_op = &proc_sops;
	460	s->s_time_gran = 1;
	461
7695650a	462	de_get(&proc_root);
1da177e4 LT	463	root_inode = proc_get_inode(s, PROC_ROOT_INO, &proc_root);
	464	if (!root_inode)
	465	goto out_no_root;
1da177e4 LT	466	root_inode->i_uid = 0;
	467	root_inode->i_gid = 0;
	468	s->s_root = d_alloc_root(root_inode);
	469	if (!s->s_root)
	470	goto out_no_root;
	471	return 0;
	472
	473	out_no_root:
	474	printk("proc_read_super: get root inode failed\n");
	475	iput(root_inode);
7695650a	476	de_put(&proc_root);
1da177e4 LT	477	return -ENOMEM;
	478	}
	479	MODULE_LICENSE("GPL");