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