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/isdnif.h>
  20 #include "isdn_divert.h"
  21
  22
  23 /*********************************/
  24 /* Variables for interface queue */
  25 /*********************************/
  26 ulong if_used = 0;              /* number of interface users */
  27 static struct divert_info *divert_info_head = NULL;     /* head of queue */
  28 static struct divert_info *divert_info_tail = NULL;     /* pointer to last entry */
  29 static DEFINE_SPINLOCK(divert_info_lock);/* lock for queue */
  30 static wait_queue_head_t rd_queue;
  31
  32 /*********************************/
  33 /* put an info buffer into queue */
  34 /*********************************/
  35 void
  36 put_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 /**********************************/
  76 static ssize_t
  77 isdn_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 /**********************************/
 104 static ssize_t
 105 isdn_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 /***************************************/
 114 static unsigned int
 115 isdn_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 /****************/
 130 static int
 131 isdn_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 /*******************/
 149 static int
 150 isdn_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 /*********/
 175 static int
 176 isdn_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
 258 static 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 /****************************/
 273 static struct proc_dir_entry *isdn_proc_entry = NULL;
 274 static 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 /***************************************************************************/
 280 int
 281 divert_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 /***************************************************************************/
 306 int
 307 divert_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 */