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 (!*((struct divert_info **) file->private_data)) {
90 if (file->f_flags & O_NONBLOCK)
91 return -EAGAIN;
92 interruptible_sleep_on(&(rd_queue));
93 }
94 if (!(inf = *((struct divert_info **) file->private_data)))
95 return (0);
96
97 inf->usage_cnt--; /* new usage count */
98 file->private_data = &inf->next; /* next structure */
99 if ((len = strlen(inf->info_start)) <= count) {
100 if (copy_to_user(buf, inf->info_start, len))
101 return -EFAULT;
102 *off += len;
103 return (len);
104 }
105 return (0);
106 } /* isdn_divert_read */
107
108 /**********************************/
109 /* deflection device write routine */
110 /**********************************/
111 static ssize_t
isdn_divert_write(struct file * file,const char __user * buf,size_t count,loff_t * off)112 isdn_divert_write(struct file *file, const char __user *buf, size_t count, loff_t *off)
113 {
114 return (-ENODEV);
115 } /* isdn_divert_write */
116
117
118 /***************************************/
119 /* select routines for various kernels */
120 /***************************************/
121 static unsigned int
isdn_divert_poll(struct file * file,poll_table * wait)122 isdn_divert_poll(struct file *file, poll_table *wait)
123 {
124 unsigned int mask = 0;
125
126 poll_wait(file, &(rd_queue), wait);
127 /* mask = POLLOUT | POLLWRNORM; */
128 if (*((struct divert_info **) file->private_data)) {
129 mask |= POLLIN | POLLRDNORM;
130 }
131 return mask;
132 } /* isdn_divert_poll */
133
134 /****************/
135 /* Open routine */
136 /****************/
137 static int
isdn_divert_open(struct inode * ino,struct file * filep)138 isdn_divert_open(struct inode *ino, struct file *filep)
139 {
140 unsigned long flags;
141
142 spin_lock_irqsave(&divert_info_lock, flags);
143 if_used++;
144 if (divert_info_head)
145 filep->private_data = &(divert_info_tail->next);
146 else
147 filep->private_data = &divert_info_head;
148 spin_unlock_irqrestore(&divert_info_lock, flags);
149 /* start_divert(); */
150 return nonseekable_open(ino, filep);
151 } /* isdn_divert_open */
152
153 /*******************/
154 /* close routine */
155 /*******************/
156 static int
isdn_divert_close(struct inode * ino,struct file * filep)157 isdn_divert_close(struct inode *ino, struct file *filep)
158 {
159 struct divert_info *inf;
160 unsigned long flags;
161
162 spin_lock_irqsave(&divert_info_lock, flags);
163 if_used--;
164 inf = *((struct divert_info **) filep->private_data);
165 while (inf) {
166 inf->usage_cnt--;
167 inf = inf->next;
168 }
169 if (if_used <= 0)
170 while (divert_info_head) {
171 inf = divert_info_head;
172 divert_info_head = divert_info_head->next;
173 kfree(inf);
174 }
175 spin_unlock_irqrestore(&divert_info_lock, flags);
176 return (0);
177 } /* isdn_divert_close */
178
179 /*********/
180 /* IOCTL */
181 /*********/
isdn_divert_ioctl_unlocked(struct file * file,uint cmd,ulong arg)182 static int isdn_divert_ioctl_unlocked(struct file *file, uint cmd, ulong arg)
183 {
184 divert_ioctl dioctl;
185 int i;
186 unsigned long flags;
187 divert_rule *rulep;
188 char *cp;
189
190 if (copy_from_user(&dioctl, (void __user *) arg, sizeof(dioctl)))
191 return -EFAULT;
192
193 switch (cmd) {
194 case IIOCGETVER:
195 dioctl.drv_version = DIVERT_IIOC_VERSION; /* set version */
196 break;
197
198 case IIOCGETDRV:
199 if ((dioctl.getid.drvid = divert_if.name_to_drv(dioctl.getid.drvnam)) < 0)
200 return (-EINVAL);
201 break;
202
203 case IIOCGETNAM:
204 cp = divert_if.drv_to_name(dioctl.getid.drvid);
205 if (!cp)
206 return (-EINVAL);
207 if (!*cp)
208 return (-EINVAL);
209 strcpy(dioctl.getid.drvnam, cp);
210 break;
211
212 case IIOCGETRULE:
213 if (!(rulep = getruleptr(dioctl.getsetrule.ruleidx)))
214 return (-EINVAL);
215 dioctl.getsetrule.rule = *rulep; /* copy data */
216 break;
217
218 case IIOCMODRULE:
219 if (!(rulep = getruleptr(dioctl.getsetrule.ruleidx)))
220 return (-EINVAL);
221 spin_lock_irqsave(&divert_lock, flags);
222 *rulep = dioctl.getsetrule.rule; /* copy data */
223 spin_unlock_irqrestore(&divert_lock, flags);
224 return (0); /* no copy required */
225 break;
226
227 case IIOCINSRULE:
228 return (insertrule(dioctl.getsetrule.ruleidx, &dioctl.getsetrule.rule));
229 break;
230
231 case IIOCDELRULE:
232 return (deleterule(dioctl.getsetrule.ruleidx));
233 break;
234
235 case IIOCDODFACT:
236 return (deflect_extern_action(dioctl.fwd_ctrl.subcmd,
237 dioctl.fwd_ctrl.callid,
238 dioctl.fwd_ctrl.to_nr));
239
240 case IIOCDOCFACT:
241 case IIOCDOCFDIS:
242 case IIOCDOCFINT:
243 if (!divert_if.drv_to_name(dioctl.cf_ctrl.drvid))
244 return (-EINVAL); /* invalid driver */
245 if (strnlen(dioctl.cf_ctrl.msn, sizeof(dioctl.cf_ctrl.msn)) ==
246 sizeof(dioctl.cf_ctrl.msn))
247 return -EINVAL;
248 if (strnlen(dioctl.cf_ctrl.fwd_nr, sizeof(dioctl.cf_ctrl.fwd_nr)) ==
249 sizeof(dioctl.cf_ctrl.fwd_nr))
250 return -EINVAL;
251 if ((i = cf_command(dioctl.cf_ctrl.drvid,
252 (cmd == IIOCDOCFACT) ? 1 : (cmd == IIOCDOCFDIS) ? 0 : 2,
253 dioctl.cf_ctrl.cfproc,
254 dioctl.cf_ctrl.msn,
255 dioctl.cf_ctrl.service,
256 dioctl.cf_ctrl.fwd_nr,
257 &dioctl.cf_ctrl.procid)))
258 return (i);
259 break;
260
261 default:
262 return (-EINVAL);
263 } /* switch cmd */
264 return copy_to_user((void __user *)arg, &dioctl, sizeof(dioctl)) ? -EFAULT : 0;
265 } /* isdn_divert_ioctl */
266
isdn_divert_ioctl(struct file * file,uint cmd,ulong arg)267 static long isdn_divert_ioctl(struct file *file, uint cmd, ulong arg)
268 {
269 long ret;
270
271 mutex_lock(&isdn_divert_mutex);
272 ret = isdn_divert_ioctl_unlocked(file, cmd, arg);
273 mutex_unlock(&isdn_divert_mutex);
274
275 return ret;
276 }
277
278 static const struct file_operations isdn_fops =
279 {
280 .owner = THIS_MODULE,
281 .llseek = no_llseek,
282 .read = isdn_divert_read,
283 .write = isdn_divert_write,
284 .poll = isdn_divert_poll,
285 .unlocked_ioctl = isdn_divert_ioctl,
286 .open = isdn_divert_open,
287 .release = isdn_divert_close,
288 };
289
290 /****************************/
291 /* isdn subdir in /proc/net */
292 /****************************/
293 static struct proc_dir_entry *isdn_proc_entry = NULL;
294 static struct proc_dir_entry *isdn_divert_entry = NULL;
295 #endif /* CONFIG_PROC_FS */
296
297 /***************************************************************************/
298 /* divert_dev_init must be called before the proc filesystem may be used */
299 /***************************************************************************/
300 int
divert_dev_init(void)301 divert_dev_init(void)
302 {
303
304 init_waitqueue_head(&rd_queue);
305
306 #ifdef CONFIG_PROC_FS
307 isdn_proc_entry = proc_mkdir("isdn", init_net.proc_net);
308 if (!isdn_proc_entry)
309 return (-1);
310 isdn_divert_entry = proc_create("divert", S_IFREG | S_IRUGO,
311 isdn_proc_entry, &isdn_fops);
312 if (!isdn_divert_entry) {
313 remove_proc_entry("isdn", init_net.proc_net);
314 return (-1);
315 }
316 #endif /* CONFIG_PROC_FS */
317
318 return (0);
319 } /* divert_dev_init */
320
321 /***************************************************************************/
322 /* divert_dev_deinit must be called before leaving isdn when included as */
323 /* a module. */
324 /***************************************************************************/
325 int
divert_dev_deinit(void)326 divert_dev_deinit(void)
327 {
328
329 #ifdef CONFIG_PROC_FS
330 remove_proc_entry("divert", isdn_proc_entry);
331 remove_proc_entry("isdn", init_net.proc_net);
332 #endif /* CONFIG_PROC_FS */
333
334 return (0);
335 } /* divert_dev_deinit */
336