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