i386/linux-2.3.21/net/atm/signaling.c

   1 /* net/atm/signaling.c - ATM signaling */
   2
   3 /* Written 1995-1999 by Werner Almesberger, EPFL LRC/ICA */
   4
   5
   6 #include <linux/errno.h>        /* error codes */
   7 #include <linux/kernel.h>       /* printk */
   8 #include <linux/skbuff.h>
   9 #include <linux/wait.h>
  10 #include <linux/sched.h>        /* jiffies and HZ */
  11 #include <linux/atm.h>          /* ATM stuff */
  12 #include <linux/atmsap.h>
  13 #include <linux/atmsvc.h>
  14 #include <linux/atmdev.h>
  15
  16 #include "tunable.h"
  17 #include "resources.h"
  18 #include "signaling.h"
  19
  20
  21 #undef WAIT_FOR_DEMON           /* #define this if system calls on SVC sockets
  22                                    should block until the demon runs.
  23                                    Danger: may cause nasty hangs if the demon
  24                                    crashes. */
  25
  26 #if 0
  27 #define DPRINTK(format,args...) printk(KERN_DEBUG format,##args)
  28 #else
  29 #define DPRINTK(format,args...)
  30 #endif
  31
  32
  33 struct atm_vcc *sigd = NULL;
  34 static wait_queue_head_t sigd_sleep;
  35
  36
  37 static void sigd_put_skb(struct sk_buff *skb)
  38 {
  39 #ifdef WAIT_FOR_DEMON
  40         static unsigned long silence = 0;
  41 #endif
  42
  43         while (!sigd) {
  44 #ifdef WAIT_FOR_DEMON
  45                 if (time_after(jiffies, silence) || silence == 0) {
  46                         printk(KERN_INFO "atmsvc: waiting for signaling demon "
  47                             "...\n");
  48                         silence = (jiffies+30*HZ)|1;
  49                 }
  50                 sleep_on(&sigd_sleep);
  51 #else
  52                 printk(KERN_WARNING "atmsvc: no signaling demon\n");
  53                 kfree_skb(skb);
  54                 return;
  55 #endif
  56         }
  57         atm_force_charge(sigd,skb->truesize);
  58         skb_queue_tail(&sigd->recvq,skb);
  59         wake_up(&sigd->sleep);
  60 }
  61
  62
  63 static void modify_qos(struct atm_vcc *vcc,struct atmsvc_msg *msg)
  64 {
  65         struct sk_buff *skb;
  66
  67         if ((vcc->flags & ATM_VF_RELEASED) || !(vcc->flags & ATM_VF_READY))
  68                 return;
  69         msg->type = as_error;
  70         if (!vcc->dev->ops->change_qos) msg->reply = -EOPNOTSUPP;
  71         else {
  72                 /* should lock VCC */
  73                 msg->reply = vcc->dev->ops->change_qos(vcc,&msg->qos,
  74                     msg->reply);
  75                 if (!msg->reply) msg->type = as_okay;
  76         }
  77         /*
  78          * Should probably just turn around the old skb. But the, the buffer
  79          * space accounting needs to follow the change too. Maybe later.
  80          */
  81         while (!(skb = alloc_skb(sizeof(struct atmsvc_msg),GFP_KERNEL)))
  82                 schedule();
  83         *(struct atmsvc_msg *) skb_put(skb,sizeof(struct atmsvc_msg)) = *msg;
  84         sigd_put_skb(skb);
  85 }
  86
  87
  88 static int sigd_send(struct atm_vcc *vcc,struct sk_buff *skb)
  89 {
  90         struct atmsvc_msg *msg;
  91         struct atm_vcc *session_vcc;
  92
  93         msg = (struct atmsvc_msg *) skb->data;
  94         atomic_sub(skb->truesize+ATM_PDU_OVHD,&vcc->tx_inuse);
  95         DPRINTK("sigd_send %d (0x%lx)\n",(int) msg->type,msg->vcc);
  96         vcc = (struct atm_vcc *) msg->vcc;
  97         switch (msg->type) {
  98                 case as_okay:
  99                         vcc->reply = msg->reply;
 100                         if (!*vcc->local.sas_addr.prv &&
 101                             !*vcc->local.sas_addr.pub) {
 102                                 vcc->local.sas_family = AF_ATMSVC;
 103                                 memcpy(vcc->local.sas_addr.prv,
 104                                     msg->local.sas_addr.prv,ATM_ESA_LEN);
 105                                 memcpy(vcc->local.sas_addr.pub,
 106                                     msg->local.sas_addr.pub,ATM_E164_LEN+1);
 107                         }
 108                         session_vcc = vcc->session ? vcc->session : vcc;
 109                         if (session_vcc->vpi || session_vcc->vci) break;
 110                         session_vcc->itf = msg->pvc.sap_addr.itf;
 111                         session_vcc->vpi = msg->pvc.sap_addr.vpi;
 112                         session_vcc->vci = msg->pvc.sap_addr.vci;
 113                         if (session_vcc->vpi || session_vcc->vci)
 114                                 session_vcc->qos = msg->qos;
 115                         break;
 116                 case as_error:
 117                         vcc->flags &= ~(ATM_VF_REGIS | ATM_VF_READY);
 118                         vcc->reply = msg->reply;
 119                         break;
 120                 case as_indicate:
 121                         vcc = (struct atm_vcc *) msg->listen_vcc;
 122                         DPRINTK("as_indicate!!!\n");
 123                         if (!vcc->backlog_quota) {
 124                                 sigd_enq(0,as_reject,vcc,NULL,NULL);
 125                                 return 0;
 126                         }
 127                         vcc->backlog_quota--;
 128                         skb_queue_tail(&vcc->listenq,skb);
 129                         if (vcc->callback) {
 130                                 DPRINTK("waking vcc->sleep 0x%p\n",
 131                                     &vcc->sleep);
 132                                 vcc->callback(vcc);
 133                         }
 134                         return 0;
 135                 case as_close:
 136                         vcc->flags |= ATM_VF_RELEASED;
 137                         vcc->flags &= ~ATM_VF_READY;
 138                         vcc->reply = msg->reply;
 139                         break;
 140                 case as_modify:
 141                         modify_qos(vcc,msg);
 142                         break;
 143                 default:
 144                         printk(KERN_ALERT "sigd_send: bad message type %d\n",
 145                             (int) msg->type);
 146                         return -EINVAL;
 147         }
 148         if (vcc->callback) vcc->callback(vcc);
 149         dev_kfree_skb(skb);
 150         return 0;
 151 }
 152
 153
 154 void sigd_enq(struct atm_vcc *vcc,enum atmsvc_msg_type type,
 155     const struct atm_vcc *listen_vcc,const struct sockaddr_atmpvc *pvc,
 156     const struct sockaddr_atmsvc *svc)
 157 {
 158         struct sk_buff *skb;
 159         struct atmsvc_msg *msg;
 160
 161         DPRINTK("sigd_enq %d (0x%p)\n",(int) type,vcc);
 162         while (!(skb = alloc_skb(sizeof(struct atmsvc_msg),GFP_KERNEL)))
 163                 schedule();
 164         msg = (struct atmsvc_msg *) skb_put(skb,sizeof(struct atmsvc_msg));
 165         msg->type = type;
 166         msg->vcc = (unsigned long) vcc;
 167         msg->listen_vcc = (unsigned long) listen_vcc;
 168         msg->reply = 0; /* other ISP applications may use this field */
 169         if (vcc) {
 170                 msg->qos = vcc->qos;
 171                 msg->sap = vcc->sap;
 172         }
 173         if (!svc) msg->svc.sas_family = 0;
 174         else msg->svc = *svc;
 175         if (vcc) msg->local = vcc->local;
 176         if (!pvc) memset(&msg->pvc,0,sizeof(msg->pvc));
 177         else msg->pvc = *pvc;
 178         sigd_put_skb(skb);
 179         if (vcc) vcc->flags |= ATM_VF_REGIS;
 180 }
 181
 182
 183 static void purge_vccs(struct atm_vcc *vcc)
 184 {
 185         while (vcc) {
 186                 if (vcc->family == PF_ATMSVC &&
 187                     !(vcc->flags & ATM_VF_META)) {
 188                         vcc->flags |= ATM_VF_RELEASED;
 189                         vcc->reply = -EUNATCH;
 190                         wake_up(&vcc->sleep);
 191                 }
 192                 vcc = vcc->next;
 193         }
 194 }
 195
 196
 197 static void sigd_close(struct atm_vcc *vcc)
 198 {
 199         struct sk_buff *skb;
 200         struct atm_dev *dev;
 201
 202         DPRINTK("sigd_close\n");
 203         sigd = NULL;
 204         if (skb_peek(&vcc->recvq))
 205                 printk(KERN_ERR "sigd_close: closing with requests pending\n");
 206         while ((skb = skb_dequeue(&vcc->recvq))) kfree_skb(skb);
 207         purge_vccs(nodev_vccs);
 208         for (dev = atm_devs; dev; dev = dev->next) purge_vccs(dev->vccs);
 209 }
 210
 211
 212 static struct atmdev_ops sigd_dev_ops = {
 213         NULL,           /* no dev_close */
 214         NULL,           /* no open */
 215         sigd_close,     /* close */
 216         NULL,           /* no ioctl */
 217         NULL,           /* no getsockopt */
 218         NULL,           /* no setsockopt */
 219         sigd_send,      /* send */
 220         NULL,           /* no sg_send */
 221         NULL,           /* no send_oam */
 222         NULL,           /* no phy_put */
 223         NULL,           /* no phy_get */
 224         NULL,           /* no feedback */
 225         NULL,           /* no change_qos */
 226         NULL            /* no free_rx_skb */
 227 };
 228
 229
 230 static struct atm_dev sigd_dev = {
 231         &sigd_dev_ops,
 232         NULL,           /* no PHY */
 233         "sig",          /* type */
 234         999,            /* dummy device number */
 235         NULL,NULL,      /* pretend not to have any VCCs */
 236         NULL,NULL,      /* no data */
 237         0,              /* no flags */
 238         NULL,           /* no local address */
 239         { 0 }           /* no ESI, no statistics */
 240 };
 241
 242
 243 int sigd_attach(struct atm_vcc *vcc)
 244 {
 245         if (sigd) return -EADDRINUSE;
 246         DPRINTK("sigd_attach\n");
 247         sigd = vcc;
 248         bind_vcc(vcc,&sigd_dev);
 249         vcc->flags |= ATM_VF_READY | ATM_VF_META;
 250         wake_up(&sigd_sleep);
 251         return 0;
 252 }
 253
 254
 255 void signaling_init(void)
 256 {
 257         init_waitqueue_head(&sigd_sleep);
 258 }