[net-next-2.6.git] / drivers / isdn / capi / capifs.c

/* $Id: capifs.c,v 1.1.2.3 2004/01/16 21:09:26 keil Exp $
 * 
 * Copyright 2000 by Carsten Paeth <calle@calle.de>
 *
 * Heavily based on devpts filesystem from H. Peter Anvin
 * 
 * This software may be used and distributed according to the terms
 * of the GNU General Public License, incorporated herein by reference.
 *
 */

#include <linux/fs.h>
#include <linux/mount.h>
#include <linux/namei.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/ctype.h>
#include <linux/sched.h>	/* current */

#include "capifs.h"

MODULE_DESCRIPTION("CAPI4Linux: /dev/capi/ filesystem");
MODULE_AUTHOR("Carsten Paeth");
MODULE_LICENSE("GPL");

/* ------------------------------------------------------------------ */

static char *revision = "$Revision: 1.1.2.3 $";

/* ------------------------------------------------------------------ */

#define CAPIFS_SUPER_MAGIC (('C'<<8)|'N')

static struct vfsmount *capifs_mnt;
static struct dentry *capifs_root;

static struct {
	int setuid;
	int setgid;
	uid_t   uid;
	gid_t   gid;
	umode_t mode;
} config = {.mode = 0600};

/* ------------------------------------------------------------------ */

static int capifs_remount(struct super_block *s, int *flags, char *data)
{
	int setuid = 0;
	int setgid = 0;
	uid_t uid = 0;
	gid_t gid = 0;
	umode_t mode = 0600;
	char *this_char;
	char *new_opt = kstrdup(data, GFP_KERNEL);

	this_char = NULL;
	while ((this_char = strsep(&data, ",")) != NULL) {
		int n;
		char dummy;
		if (!*this_char)
			continue;
		if (sscanf(this_char, "uid=%i%c", &n, &dummy) == 1) {
			setuid = 1;
			uid = n;
		} else if (sscanf(this_char, "gid=%i%c", &n, &dummy) == 1) {
			setgid = 1;
			gid = n;
		} else if (sscanf(this_char, "mode=%o%c", &n, &dummy) == 1)
			mode = n & ~S_IFMT;
		else {
			printk("capifs: called with bogus options\n");
			return -EINVAL;
		}
	}

	kfree(s->s_options);
	s->s_options = new_opt;

	config.setuid  = setuid;
	config.setgid  = setgid;
	config.uid     = uid;
	config.gid     = gid;
	config.mode    = mode;

	return 0;
}

static struct super_operations capifs_sops =
{
	.statfs		= simple_statfs,
	.remount_fs	= capifs_remount,
	.show_options	= generic_show_options,
};


static int
capifs_fill_super(struct super_block *s, void *data, int silent)
{
	struct inode * inode;

	s->s_blocksize = 1024;
	s->s_blocksize_bits = 10;
	s->s_magic = CAPIFS_SUPER_MAGIC;
	s->s_op = &capifs_sops;
	s->s_time_gran = 1;

	inode = new_inode(s);
	if (!inode)
		goto fail;
	inode->i_ino = 1;
	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
	inode->i_blocks = 0;
	inode->i_uid = inode->i_gid = 0;
	inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO | S_IWUSR;
	inode->i_op = &simple_dir_inode_operations;
	inode->i_fop = &simple_dir_operations;
	inode->i_nlink = 2;

	capifs_root = s->s_root = d_alloc_root(inode);
	if (s->s_root)
		return 0;
	
	printk("capifs: get root dentry failed\n");
	iput(inode);
fail:
	return -ENOMEM;
}

static int capifs_get_sb(struct file_system_type *fs_type,
	int flags, const char *dev_name, void *data, struct vfsmount *mnt)
{
	return get_sb_single(fs_type, flags, data, capifs_fill_super, mnt);
}

static struct file_system_type capifs_fs_type = {
	.owner		= THIS_MODULE,
	.name		= "capifs",
	.get_sb		= capifs_get_sb,
	.kill_sb	= kill_anon_super,
};

static struct dentry *get_node(int num)
{
	char s[10];
	struct dentry *root = capifs_root;
	mutex_lock(&root->d_inode->i_mutex);
	return lookup_one_len(s, root, sprintf(s, "%d", num));
}

void capifs_new_ncci(unsigned int number, dev_t device)
{
	struct dentry *dentry;
	struct inode *inode = new_inode(capifs_mnt->mnt_sb);
	if (!inode)
		return;
	inode->i_ino = number+2;
	inode->i_uid = config.setuid ? config.uid : current->fsuid;
	inode->i_gid = config.setgid ? config.gid : current->fsgid;
	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
	init_special_inode(inode, S_IFCHR|config.mode, device);
	//inode->i_op = &capifs_file_inode_operations;

	dentry = get_node(number);
	if (!IS_ERR(dentry) && !dentry->d_inode)
		d_instantiate(dentry, inode);
	mutex_unlock(&capifs_root->d_inode->i_mutex);
}

void capifs_free_ncci(unsigned int number)
{
	struct dentry *dentry = get_node(number);

	if (!IS_ERR(dentry)) {
		struct inode *inode = dentry->d_inode;
		if (inode) {
			inode->i_nlink--;
			d_delete(dentry);
			dput(dentry);
		}
		dput(dentry);
	}
	mutex_unlock(&capifs_root->d_inode->i_mutex);
}

static int __init capifs_init(void)
{
	char rev[32];
	char *p;
	int err;

	if ((p = strchr(revision, ':')) != NULL && p[1]) {
		strlcpy(rev, p + 2, sizeof(rev));
		if ((p = strchr(rev, '$')) != NULL && p > rev)
		   *(p-1) = 0;
	} else
		strcpy(rev, "1.0");

	err = register_filesystem(&capifs_fs_type);
	if (!err) {
		capifs_mnt = kern_mount(&capifs_fs_type);
		if (IS_ERR(capifs_mnt)) {
			err = PTR_ERR(capifs_mnt);
			unregister_filesystem(&capifs_fs_type);
		}
	}
	if (!err)
		printk(KERN_NOTICE "capifs: Rev %s\n", rev);
	return err;
}

static void __exit capifs_exit(void)
{
	unregister_filesystem(&capifs_fs_type);
	mntput(capifs_mnt);
}

EXPORT_SYMBOL(capifs_new_ncci);
EXPORT_SYMBOL(capifs_free_ncci);

module_init(capifs_init);
module_exit(capifs_exit);
Commit	Line	Data
1da177e4 LT	1	/* $Id: capifs.c,v 1.1.2.3 2004/01/16 21:09:26 keil Exp $
	2	*
	3	* Copyright 2000 by Carsten Paeth <calle@calle.de>
	4	*
	5	* Heavily based on devpts filesystem from H. Peter Anvin
	6	*
	7	* This software may be used and distributed according to the terms
	8	* of the GNU General Public License, incorporated herein by reference.
	9	*
	10	*/
	11
	12	#include <linux/fs.h>
	13	#include <linux/mount.h>
	14	#include <linux/namei.h>
	15	#include <linux/module.h>
	16	#include <linux/init.h>
	17	#include <linux/ctype.h>
4e57b681	18	#include <linux/sched.h> /* current */
1da177e4	19
6e21bd9a AB	20	#include "capifs.h"
6e21bd9a AB	21
1da177e4 LT	22	MODULE_DESCRIPTION("CAPI4Linux: /dev/capi/ filesystem");
	23	MODULE_AUTHOR("Carsten Paeth");
	24	MODULE_LICENSE("GPL");
	25
	26	/* ------------------------------------------------------------------ */
	27
	28	static char *revision = "$Revision: 1.1.2.3 $";
	29
	30	/* ------------------------------------------------------------------ */
	31
	32	#define CAPIFS_SUPER_MAGIC (('C'<<8)\|'N')
	33
	34	static struct vfsmount *capifs_mnt;
	35	static struct dentry *capifs_root;
	36
	37	static struct {
	38	int setuid;
	39	int setgid;
	40	uid_t uid;
	41	gid_t gid;
	42	umode_t mode;
	43	} config = {.mode = 0600};
	44
	45	/* ------------------------------------------------------------------ */
	46
	47	static int capifs_remount(struct super_block s, int flags, char *data)
	48	{
	49	int setuid = 0;
	50	int setgid = 0;
	51	uid_t uid = 0;
	52	gid_t gid = 0;
	53	umode_t mode = 0600;
	54	char *this_char;
e55e212c	55	char *new_opt = kstrdup(data, GFP_KERNEL);
1da177e4 LT	56
	57	this_char = NULL;
	58	while ((this_char = strsep(&data, ",")) != NULL) {
	59	int n;
	60	char dummy;
	61	if (!*this_char)
	62	continue;
	63	if (sscanf(this_char, "uid=%i%c", &n, &dummy) == 1) {
	64	setuid = 1;
	65	uid = n;
	66	} else if (sscanf(this_char, "gid=%i%c", &n, &dummy) == 1) {
	67	setgid = 1;
	68	gid = n;
	69	} else if (sscanf(this_char, "mode=%o%c", &n, &dummy) == 1)
	70	mode = n & ~S_IFMT;
	71	else {
	72	printk("capifs: called with bogus options\n");
	73	return -EINVAL;
	74	}
	75	}
e55e212c MS	76
	77	kfree(s->s_options);
	78	s->s_options = new_opt;
	79
1da177e4 LT	80	config.setuid = setuid;
	81	config.setgid = setgid;
	82	config.uid = uid;
	83	config.gid = gid;
	84	config.mode = mode;
e55e212c	85
1da177e4 LT	86	return 0;
	87	}
	88
	89	static struct super_operations capifs_sops =
	90	{
	91	.statfs = simple_statfs,
	92	.remount_fs = capifs_remount,
e55e212c	93	.show_options = generic_show_options,
1da177e4 LT	94	};
	95
	96
	97	static int
	98	capifs_fill_super(struct super_block s, void data, int silent)
	99	{
	100	struct inode * inode;
	101
	102	s->s_blocksize = 1024;
	103	s->s_blocksize_bits = 10;
	104	s->s_magic = CAPIFS_SUPER_MAGIC;
	105	s->s_op = &capifs_sops;
	106	s->s_time_gran = 1;
	107
	108	inode = new_inode(s);
	109	if (!inode)
	110	goto fail;
	111	inode->i_ino = 1;
	112	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
	113	inode->i_blocks = 0;
1da177e4 LT	114	inode->i_uid = inode->i_gid = 0;
	115	inode->i_mode = S_IFDIR \| S_IRUGO \| S_IXUGO \| S_IWUSR;
	116	inode->i_op = &simple_dir_inode_operations;
	117	inode->i_fop = &simple_dir_operations;
	118	inode->i_nlink = 2;
	119
	120	capifs_root = s->s_root = d_alloc_root(inode);
	121	if (s->s_root)
	122	return 0;
	123
	124	printk("capifs: get root dentry failed\n");
	125	iput(inode);
	126	fail:
	127	return -ENOMEM;
	128	}
	129
454e2398 DH	130	static int capifs_get_sb(struct file_system_type *fs_type,
454e2398 DH	131	int flags, const char dev_name, void data, struct vfsmount *mnt)
1da177e4	132	{
454e2398	133	return get_sb_single(fs_type, flags, data, capifs_fill_super, mnt);
1da177e4 LT	134	}
	135
	136	static struct file_system_type capifs_fs_type = {
	137	.owner = THIS_MODULE,
	138	.name = "capifs",
	139	.get_sb = capifs_get_sb,
	140	.kill_sb = kill_anon_super,
	141	};
	142
	143	static struct dentry *get_node(int num)
	144	{
	145	char s[10];
	146	struct dentry *root = capifs_root;
1b1dcc1b	147	mutex_lock(&root->d_inode->i_mutex);
1da177e4 LT	148	return lookup_one_len(s, root, sprintf(s, "%d", num));
	149	}
	150
	151	void capifs_new_ncci(unsigned int number, dev_t device)
	152	{
	153	struct dentry *dentry;
	154	struct inode *inode = new_inode(capifs_mnt->mnt_sb);
	155	if (!inode)
	156	return;
	157	inode->i_ino = number+2;
1da177e4 LT	158	inode->i_uid = config.setuid ? config.uid : current->fsuid;
	159	inode->i_gid = config.setgid ? config.gid : current->fsgid;
	160	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
	161	init_special_inode(inode, S_IFCHR\|config.mode, device);
	162	//inode->i_op = &capifs_file_inode_operations;
	163
	164	dentry = get_node(number);
	165	if (!IS_ERR(dentry) && !dentry->d_inode)
	166	d_instantiate(dentry, inode);
1b1dcc1b	167	mutex_unlock(&capifs_root->d_inode->i_mutex);
1da177e4 LT	168	}
	169
	170	void capifs_free_ncci(unsigned int number)
	171	{
	172	struct dentry *dentry = get_node(number);
	173
	174	if (!IS_ERR(dentry)) {
	175	struct inode *inode = dentry->d_inode;
	176	if (inode) {
	177	inode->i_nlink--;
	178	d_delete(dentry);
	179	dput(dentry);
	180	}
	181	dput(dentry);
	182	}
1b1dcc1b	183	mutex_unlock(&capifs_root->d_inode->i_mutex);
1da177e4 LT	184	}
	185
	186	static int __init capifs_init(void)
	187	{
	188	char rev[32];
	189	char *p;
	190	int err;
	191
2f9e9b6d	192	if ((p = strchr(revision, ':')) != NULL && p[1]) {
1da177e4	193	strlcpy(rev, p + 2, sizeof(rev));
2f9e9b6d	194	if ((p = strchr(rev, '$')) != NULL && p > rev)
1da177e4 LT	195	*(p-1) = 0;
	196	} else
	197	strcpy(rev, "1.0");
	198
	199	err = register_filesystem(&capifs_fs_type);
	200	if (!err) {
	201	capifs_mnt = kern_mount(&capifs_fs_type);
820d220d	202	if (IS_ERR(capifs_mnt)) {
1da177e4	203	err = PTR_ERR(capifs_mnt);
820d220d JM	204	unregister_filesystem(&capifs_fs_type);
820d220d JM	205	}
1da177e4 LT	206	}
	207	if (!err)
	208	printk(KERN_NOTICE "capifs: Rev %s\n", rev);
	209	return err;
	210	}
	211
	212	static void __exit capifs_exit(void)
	213	{
	214	unregister_filesystem(&capifs_fs_type);
	215	mntput(capifs_mnt);
	216	}
	217
	218	EXPORT_SYMBOL(capifs_new_ncci);
	219	EXPORT_SYMBOL(capifs_free_ncci);
	220
	221	module_init(capifs_init);
	222	module_exit(capifs_exit);