drivers/isdn/divert/divert_procfs.c

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