1/* $Id: divert_procfs.c,v 1.1.1.1 2007/08/03 18:52:34 Exp $
2 *
3 * Filesystem handling for the diversion supplementary services.
4 *
5 * Copyright 1998       by Werner Cornelius (werner@isdn4linux.de)
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/module.h>
13#include <linux/poll.h>
14#ifdef CONFIG_PROC_FS
15#include <linux/proc_fs.h>
16#else
17#include <linux/fs.h>
18#endif
19#include <linux/isdnif.h>
20#include "isdn_divert.h"
21
22
23/*********************************/
24/* Variables for interface queue */
25/*********************************/
26ulong if_used = 0;		/* number of interface users */
27static struct divert_info *divert_info_head = NULL;	/* head of queue */
28static struct divert_info *divert_info_tail = NULL;	/* pointer to last entry */
29static DEFINE_SPINLOCK(divert_info_lock);/* lock for queue */
30static wait_queue_head_t rd_queue;
31
32/*********************************/
33/* put an info buffer into queue */
34/*********************************/
35void
36put_info_buffer(char *cp)
37{
38	struct divert_info *ib;
39	unsigned long flags;
40
41	if (if_used <= 0)
42		return;
43	if (!cp)
44		return;
45	if (!*cp)
46		return;
47	if (!(ib = kmalloc(sizeof(struct divert_info) + strlen(cp), GFP_ATOMIC)))
48		 return;	/* no memory */
49	strcpy(ib->info_start, cp);	/* set output string */
50	ib->next = NULL;
51	spin_lock_irqsave( &divert_info_lock, flags );
52	ib->usage_cnt = if_used;
53	if (!divert_info_head)
54		divert_info_head = ib;	/* new head */
55	else
56		divert_info_tail->next = ib;	/* follows existing messages */
57	divert_info_tail = ib;	/* new tail */
58
59	/* delete old entrys */
60	while (divert_info_head->next) {
61		if ((divert_info_head->usage_cnt <= 0) &&
62		    (divert_info_head->next->usage_cnt <= 0)) {
63			ib = divert_info_head;
64			divert_info_head = divert_info_head->next;
65			kfree(ib);
66		} else
67			break;
68	}			/* divert_info_head->next */
69	spin_unlock_irqrestore( &divert_info_lock, flags );
70	wake_up_interruptible(&(rd_queue));
71}				/* put_info_buffer */
72
73/**********************************/
74/* deflection device read routine */
75/**********************************/
76static ssize_t
77isdn_divert_read(struct file *file, char __user *buf, size_t count, loff_t * off)
78{
79	struct divert_info *inf;
80	int len;
81
82	if (!*((struct divert_info **) file->private_data)) {
83		if (file->f_flags & O_NONBLOCK)
84			return -EAGAIN;
85		interruptible_sleep_on(&(rd_queue));
86	}
87	if (!(inf = *((struct divert_info **) file->private_data)))
88		return (0);
89
90	inf->usage_cnt--;	/* new usage count */
91	file->private_data = &inf->next;	/* next structure */
92	if ((len = strlen(inf->info_start)) <= count) {
93		if (copy_to_user(buf, inf->info_start, len))
94			return -EFAULT;
95		*off += len;
96		return (len);
97	}
98	return (0);
99}				/* isdn_divert_read */
100
101/**********************************/
102/* deflection device write routine */
103/**********************************/
104static ssize_t
105isdn_divert_write(struct file *file, const char __user *buf, size_t count, loff_t * off)
106{
107	return (-ENODEV);
108}				/* isdn_divert_write */
109
110
111/***************************************/
112/* select routines for various kernels */
113/***************************************/
114static unsigned int
115isdn_divert_poll(struct file *file, poll_table * wait)
116{
117	unsigned int mask = 0;
118
119	poll_wait(file, &(rd_queue), wait);
120	/* mask = POLLOUT | POLLWRNORM; */
121	if (*((struct divert_info **) file->private_data)) {
122		mask |= POLLIN | POLLRDNORM;
123	}
124	return mask;
125}				/* isdn_divert_poll */
126
127/****************/
128/* Open routine */
129/****************/
130static int
131isdn_divert_open(struct inode *ino, struct file *filep)
132{
133	unsigned long flags;
134
135	spin_lock_irqsave( &divert_info_lock, flags );
136 	if_used++;
137	if (divert_info_head)
138		filep->private_data = &(divert_info_tail->next);
139	else
140		filep->private_data = &divert_info_head;
141	spin_unlock_irqrestore( &divert_info_lock, flags );
142	/*  start_divert(); */
143	return nonseekable_open(ino, filep);
144}				/* isdn_divert_open */
145
146/*******************/
147/* close routine   */
148/*******************/
149static int
150isdn_divert_close(struct inode *ino, struct file *filep)
151{
152	struct divert_info *inf;
153	unsigned long flags;
154
155	spin_lock_irqsave( &divert_info_lock, flags );
156	if_used--;
157	inf = *((struct divert_info **) filep->private_data);
158	while (inf) {
159		inf->usage_cnt--;
160		inf = inf->next;
161	}
162	if (if_used <= 0)
163		while (divert_info_head) {
164			inf = divert_info_head;
165			divert_info_head = divert_info_head->next;
166			kfree(inf);
167		}
168	spin_unlock_irqrestore( &divert_info_lock, flags );
169	return (0);
170}				/* isdn_divert_close */
171
172/*********/
173/* IOCTL */
174/*********/
175static int
176isdn_divert_ioctl(struct inode *inode, struct file *file,
177		  uint cmd, ulong arg)
178{
179	divert_ioctl dioctl;
180	int i;
181	unsigned long flags;
182	divert_rule *rulep;
183	char *cp;
184
185	if (copy_from_user(&dioctl, (void __user *) arg, sizeof(dioctl)))
186		return -EFAULT;
187
188	switch (cmd) {
189		case IIOCGETVER:
190			dioctl.drv_version = DIVERT_IIOC_VERSION;	/* set version */
191			break;
192
193		case IIOCGETDRV:
194			if ((dioctl.getid.drvid = divert_if.name_to_drv(dioctl.getid.drvnam)) < 0)
195				return (-EINVAL);
196			break;
197
198		case IIOCGETNAM:
199			cp = divert_if.drv_to_name(dioctl.getid.drvid);
200			if (!cp)
201				return (-EINVAL);
202			if (!*cp)
203				return (-EINVAL);
204			strcpy(dioctl.getid.drvnam, cp);
205			break;
206
207		case IIOCGETRULE:
208			if (!(rulep = getruleptr(dioctl.getsetrule.ruleidx)))
209				return (-EINVAL);
210			dioctl.getsetrule.rule = *rulep;	/* copy data */
211			break;
212
213		case IIOCMODRULE:
214			if (!(rulep = getruleptr(dioctl.getsetrule.ruleidx)))
215				return (-EINVAL);
216            spin_lock_irqsave(&divert_lock, flags);
217			*rulep = dioctl.getsetrule.rule;	/* copy data */
218			spin_unlock_irqrestore(&divert_lock, flags);
219			return (0);	/* no copy required */
220			break;
221
222		case IIOCINSRULE:
223			return (insertrule(dioctl.getsetrule.ruleidx, &dioctl.getsetrule.rule));
224			break;
225
226		case IIOCDELRULE:
227			return (deleterule(dioctl.getsetrule.ruleidx));
228			break;
229
230		case IIOCDODFACT:
231			return (deflect_extern_action(dioctl.fwd_ctrl.subcmd,
232						  dioctl.fwd_ctrl.callid,
233						 dioctl.fwd_ctrl.to_nr));
234
235		case IIOCDOCFACT:
236		case IIOCDOCFDIS:
237		case IIOCDOCFINT:
238			if (!divert_if.drv_to_name(dioctl.cf_ctrl.drvid))
239				return (-EINVAL);	/* invalid driver */
240			if ((i = cf_command(dioctl.cf_ctrl.drvid,
241					    (cmd == IIOCDOCFACT) ? 1 : (cmd == IIOCDOCFDIS) ? 0 : 2,
242					    dioctl.cf_ctrl.cfproc,
243					    dioctl.cf_ctrl.msn,
244					    dioctl.cf_ctrl.service,
245					    dioctl.cf_ctrl.fwd_nr,
246					    &dioctl.cf_ctrl.procid)))
247				return (i);
248			break;
249
250		default:
251			return (-EINVAL);
252	}			/* switch cmd */
253	return copy_to_user((void __user *)arg, &dioctl, sizeof(dioctl)) ? -EFAULT : 0;
254}				/* isdn_divert_ioctl */
255
256
257#ifdef CONFIG_PROC_FS
258static const struct file_operations isdn_fops =
259{
260	.owner          = THIS_MODULE,
261	.llseek         = no_llseek,
262	.read           = isdn_divert_read,
263	.write          = isdn_divert_write,
264	.poll           = isdn_divert_poll,
265	.ioctl          = isdn_divert_ioctl,
266	.open           = isdn_divert_open,
267	.release        = isdn_divert_close,
268};
269
270/****************************/
271/* isdn subdir in /proc/net */
272/****************************/
273static struct proc_dir_entry *isdn_proc_entry = NULL;
274static struct proc_dir_entry *isdn_divert_entry = NULL;
275#endif	/* CONFIG_PROC_FS */
276
277/***************************************************************************/
278/* divert_dev_init must be called before the proc filesystem may be used   */
279/***************************************************************************/
280int
281divert_dev_init(void)
282{
283
284	init_waitqueue_head(&rd_queue);
285
286#ifdef CONFIG_PROC_FS
287	isdn_proc_entry = proc_mkdir("net/isdn", NULL);
288	if (!isdn_proc_entry)
289		return (-1);
290	isdn_divert_entry = create_proc_entry("divert", S_IFREG | S_IRUGO, isdn_proc_entry);
291	if (!isdn_divert_entry) {
292		remove_proc_entry("net/isdn", NULL);
293		return (-1);
294	}
295	isdn_divert_entry->proc_fops = &isdn_fops;
296	isdn_divert_entry->owner = THIS_MODULE;
297#endif	/* CONFIG_PROC_FS */
298
299	return (0);
300}				/* divert_dev_init */
301
302/***************************************************************************/
303/* divert_dev_deinit must be called before leaving isdn when included as   */
304/* a module.                                                               */
305/***************************************************************************/
306int
307divert_dev_deinit(void)
308{
309
310#ifdef CONFIG_PROC_FS
311	remove_proc_entry("divert", isdn_proc_entry);
312	remove_proc_entry("net/isdn", NULL);
313#endif	/* CONFIG_PROC_FS */
314
315	return (0);
316}				/* divert_dev_deinit */
317