1 /* $Id: divert_procfs.c,v 1.11.6.2 2001/09/23 22:24:36 kai 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 #include <linux/slab.h>
15 #ifdef CONFIG_PROC_FS
16 #include <linux/proc_fs.h>
17 #else
18 #include <linux/fs.h>
19 #endif
20 #include <linux/sched.h>
21 #include <linux/isdnif.h>
22 #include <net/net_namespace.h>
23 #include <linux/mutex.h>
24 #include "isdn_divert.h"
25
26
27 /*********************************/
28 /* Variables for interface queue */
29 /*********************************/
30 ulong if_used = 0; /* number of interface users */
31 static DEFINE_MUTEX(isdn_divert_mutex);
32 static struct divert_info *divert_info_head = NULL; /* head of queue */
33 static struct divert_info *divert_info_tail = NULL; /* pointer to last entry */
34 static DEFINE_SPINLOCK(divert_info_lock);/* lock for queue */
35 static wait_queue_head_t rd_queue;
36
37 /*********************************/
38 /* put an info buffer into queue */
39 /*********************************/
40 void
put_info_buffer(char * cp)41 put_info_buffer(char *cp)
42 {
43 struct divert_info *ib;
44 unsigned long flags;
45
46 if (if_used <= 0)
47 return;
48 if (!cp)
49 return;
50 if (!*cp)
51 return;
52 if (!(ib = kmalloc(sizeof(struct divert_info) + strlen(cp), GFP_ATOMIC)))
53 return; /* no memory */
54 strcpy(ib->info_start, cp); /* set output string */
55 ib->next = NULL;
56 spin_lock_irqsave(&divert_info_lock, flags);
57 ib->usage_cnt = if_used;
58 if (!divert_info_head)
59 divert_info_head = ib; /* new head */
60 else
61 divert_info_tail->next = ib; /* follows existing messages */
62 divert_info_tail = ib; /* new tail */
63
64 /* delete old entrys */
65 while (divert_info_head->next) {
66 if ((divert_info_head->usage_cnt <= 0) &&
67 (divert_info_head->next->usage_cnt <= 0)) {
68 ib = divert_info_head;
69 divert_info_head = divert_info_head->next;
70 kfree(ib);
71 } else
72 break;
73 } /* divert_info_head->next */
74 spin_unlock_irqrestore(&divert_info_lock, flags);
75 wake_up_interruptible(&(rd_queue));
76 } /* put_info_buffer */
77
78 #ifdef CONFIG_PROC_FS
79
80 /**********************************/
81 /* deflection device read routine */
82 /**********************************/
83 static ssize_t
isdn_divert_read(struct file * file,char __user * buf,size_t count,loff_t * off)84 isdn_divert_read(struct file *file, char __user *buf, size_t count, loff_t *off)
85 {
86 struct divert_info *inf;
87 int len;
88
89 if (!(inf = *((struct divert_info **) file->private_data))) {
90 if (file->f_flags & O_NONBLOCK)
91 return -EAGAIN;
92 wait_event_interruptible(rd_queue, (inf =
93 *((struct divert_info **) file->private_data)));
94 }
95 if (!inf)
96 return (0);
97
98 inf->usage_cnt--; /* new usage count */
99 file->private_data = &inf->next; /* next structure */
100 if ((len = strlen(inf->info_start)) <= count) {
101 if (copy_to_user(buf, inf->info_start, len))
102 return -EFAULT;
103 *off += len;
104 return (len);
105 }
106 return (0);
107 } /* isdn_divert_read */
108
109 /**********************************/
110 /* deflection device write routine */
111 /**********************************/
112 static ssize_t
isdn_divert_write(struct file * file,const char __user * buf,size_t count,loff_t * off)113 isdn_divert_write(struct file *file, const char __user *buf, size_t count, loff_t *off)
114 {
115 return (-ENODEV);
116 } /* isdn_divert_write */
117
118
119 /***************************************/
120 /* select routines for various kernels */
121 /***************************************/
122 static __poll_t
isdn_divert_poll(struct file * file,poll_table * wait)123 isdn_divert_poll(struct file *file, poll_table *wait)
124 {
125 __poll_t mask = 0;
126
127 poll_wait(file, &(rd_queue), wait);
128 /* mask = EPOLLOUT | EPOLLWRNORM; */
129 if (*((struct divert_info **) file->private_data)) {
130 mask |= EPOLLIN | EPOLLRDNORM;
131 }
132 return mask;
133 } /* isdn_divert_poll */
134
135 /****************/
136 /* Open routine */
137 /****************/
138 static int
isdn_divert_open(struct inode * ino,struct file * filep)139 isdn_divert_open(struct inode *ino, struct file *filep)
140 {
141 unsigned long flags;
142
143 spin_lock_irqsave(&divert_info_lock, flags);
144 if_used++;
145 if (divert_info_head)
146 filep->private_data = &(divert_info_tail->next);
147 else
148 filep->private_data = &divert_info_head;
149 spin_unlock_irqrestore(&divert_info_lock, flags);
150 /* start_divert(); */
151 return nonseekable_open(ino, filep);
152 } /* isdn_divert_open */
153
154 /*******************/
155 /* close routine */
156 /*******************/
157 static int
isdn_divert_close(struct inode * ino,struct file * filep)158 isdn_divert_close(struct inode *ino, struct file *filep)
159 {
160 struct divert_info *inf;
161 unsigned long flags;
162
163 spin_lock_irqsave(&divert_info_lock, flags);
164 if_used--;
165 inf = *((struct divert_info **) filep->private_data);
166 while (inf) {
167 inf->usage_cnt--;
168 inf = inf->next;
169 }
170 if (if_used <= 0)
171 while (divert_info_head) {
172 inf = divert_info_head;
173 divert_info_head = divert_info_head->next;
174 kfree(inf);
175 }
176 spin_unlock_irqrestore(&divert_info_lock, flags);
177 return (0);
178 } /* isdn_divert_close */
179
180 /*********/
181 /* IOCTL */
182 /*********/
isdn_divert_ioctl_unlocked(struct file * file,uint cmd,ulong arg)183 static int isdn_divert_ioctl_unlocked(struct file *file, uint cmd, ulong arg)
184 {
185 divert_ioctl dioctl;
186 int i;
187 unsigned long flags;
188 divert_rule *rulep;
189 char *cp;
190
191 if (copy_from_user(&dioctl, (void __user *) arg, sizeof(dioctl)))
192 return -EFAULT;
193
194 switch (cmd) {
195 case IIOCGETVER:
196 dioctl.drv_version = DIVERT_IIOC_VERSION; /* set version */
197 break;
198
199 case IIOCGETDRV:
200 if ((dioctl.getid.drvid = divert_if.name_to_drv(dioctl.getid.drvnam)) < 0)
201 return (-EINVAL);
202 break;
203
204 case IIOCGETNAM:
205 cp = divert_if.drv_to_name(dioctl.getid.drvid);
206 if (!cp)
207 return (-EINVAL);
208 if (!*cp)
209 return (-EINVAL);
210 strcpy(dioctl.getid.drvnam, cp);
211 break;
212
213 case IIOCGETRULE:
214 if (!(rulep = getruleptr(dioctl.getsetrule.ruleidx)))
215 return (-EINVAL);
216 dioctl.getsetrule.rule = *rulep; /* copy data */
217 break;
218
219 case IIOCMODRULE:
220 if (!(rulep = getruleptr(dioctl.getsetrule.ruleidx)))
221 return (-EINVAL);
222 spin_lock_irqsave(&divert_lock, flags);
223 *rulep = dioctl.getsetrule.rule; /* copy data */
224 spin_unlock_irqrestore(&divert_lock, flags);
225 return (0); /* no copy required */
226 break;
227
228 case IIOCINSRULE:
229 return (insertrule(dioctl.getsetrule.ruleidx, &dioctl.getsetrule.rule));
230 break;
231
232 case IIOCDELRULE:
233 return (deleterule(dioctl.getsetrule.ruleidx));
234 break;
235
236 case IIOCDODFACT:
237 return (deflect_extern_action(dioctl.fwd_ctrl.subcmd,
238 dioctl.fwd_ctrl.callid,
239 dioctl.fwd_ctrl.to_nr));
240
241 case IIOCDOCFACT:
242 case IIOCDOCFDIS:
243 case IIOCDOCFINT:
244 if (!divert_if.drv_to_name(dioctl.cf_ctrl.drvid))
245 return (-EINVAL); /* invalid driver */
246 if (strnlen(dioctl.cf_ctrl.msn, sizeof(dioctl.cf_ctrl.msn)) ==
247 sizeof(dioctl.cf_ctrl.msn))
248 return -EINVAL;
249 if (strnlen(dioctl.cf_ctrl.fwd_nr, sizeof(dioctl.cf_ctrl.fwd_nr)) ==
250 sizeof(dioctl.cf_ctrl.fwd_nr))
251 return -EINVAL;
252 if ((i = cf_command(dioctl.cf_ctrl.drvid,
253 (cmd == IIOCDOCFACT) ? 1 : (cmd == IIOCDOCFDIS) ? 0 : 2,
254 dioctl.cf_ctrl.cfproc,
255 dioctl.cf_ctrl.msn,
256 dioctl.cf_ctrl.service,
257 dioctl.cf_ctrl.fwd_nr,
258 &dioctl.cf_ctrl.procid)))
259 return (i);
260 break;
261
262 default:
263 return (-EINVAL);
264 } /* switch cmd */
265 return copy_to_user((void __user *)arg, &dioctl, sizeof(dioctl)) ? -EFAULT : 0;
266 } /* isdn_divert_ioctl */
267
isdn_divert_ioctl(struct file * file,uint cmd,ulong arg)268 static long isdn_divert_ioctl(struct file *file, uint cmd, ulong arg)
269 {
270 long ret;
271
272 mutex_lock(&isdn_divert_mutex);
273 ret = isdn_divert_ioctl_unlocked(file, cmd, arg);
274 mutex_unlock(&isdn_divert_mutex);
275
276 return ret;
277 }
278
279 static const struct file_operations isdn_fops =
280 {
281 .owner = THIS_MODULE,
282 .llseek = no_llseek,
283 .read = isdn_divert_read,
284 .write = isdn_divert_write,
285 .poll = isdn_divert_poll,
286 .unlocked_ioctl = isdn_divert_ioctl,
287 .open = isdn_divert_open,
288 .release = isdn_divert_close,
289 };
290
291 /****************************/
292 /* isdn subdir in /proc/net */
293 /****************************/
294 static struct proc_dir_entry *isdn_proc_entry = NULL;
295 static struct proc_dir_entry *isdn_divert_entry = NULL;
296 #endif /* CONFIG_PROC_FS */
297
298 /***************************************************************************/
299 /* divert_dev_init must be called before the proc filesystem may be used */
300 /***************************************************************************/
301 int
divert_dev_init(void)302 divert_dev_init(void)
303 {
304
305 init_waitqueue_head(&rd_queue);
306
307 #ifdef CONFIG_PROC_FS
308 isdn_proc_entry = proc_mkdir("isdn", init_net.proc_net);
309 if (!isdn_proc_entry)
310 return (-1);
311 isdn_divert_entry = proc_create("divert", S_IFREG | S_IRUGO,
312 isdn_proc_entry, &isdn_fops);
313 if (!isdn_divert_entry) {
314 remove_proc_entry("isdn", init_net.proc_net);
315 return (-1);
316 }
317 #endif /* CONFIG_PROC_FS */
318
319 return (0);
320 } /* divert_dev_init */
321
322 /***************************************************************************/
323 /* divert_dev_deinit must be called before leaving isdn when included as */
324 /* a module. */
325 /***************************************************************************/
326 int
divert_dev_deinit(void)327 divert_dev_deinit(void)
328 {
329
330 #ifdef CONFIG_PROC_FS
331 remove_proc_entry("divert", isdn_proc_entry);
332 remove_proc_entry("isdn", init_net.proc_net);
333 #endif /* CONFIG_PROC_FS */
334
335 return (0);
336 } /* divert_dev_deinit */
337
