signaling.c revision 208a6dfbd651f3a16c635678a731b419d3d9646f
1/* net/atm/signaling.c - ATM signaling */ 2 3/* Written 1995-2000 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#include <linux/bitops.h> 16 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 33struct atm_vcc *sigd = NULL; 34#ifdef WAIT_FOR_DEMON 35static DECLARE_WAIT_QUEUE_HEAD(sigd_sleep); 36#endif 37 38 39static void sigd_put_skb(struct sk_buff *skb) 40{ 41#ifdef WAIT_FOR_DEMON 42 static unsigned long silence; 43 DECLARE_WAITQUEUE(wait,current); 44 45 add_wait_queue(&sigd_sleep,&wait); 46 while (!sigd) { 47 set_current_state(TASK_UNINTERRUPTIBLE); 48 if (time_after(jiffies, silence) || silence == 0) { 49 printk(KERN_INFO "atmsvc: waiting for signaling demon " 50 "...\n"); 51 silence = (jiffies+30*HZ)|1; 52 } 53 schedule(); 54 } 55 current->state = TASK_RUNNING; 56 remove_wait_queue(&sigd_sleep,&wait); 57#else 58 if (!sigd) { 59 printk(KERN_WARNING "atmsvc: no signaling demon\n"); 60 kfree_skb(skb); 61 return; 62 } 63#endif 64 atm_force_charge(sigd,skb->truesize); 65 skb_queue_tail(&sk_atm(sigd)->sk_receive_queue,skb); 66 sk_atm(sigd)->sk_data_ready(sk_atm(sigd), skb->len); 67} 68 69 70static void modify_qos(struct atm_vcc *vcc,struct atmsvc_msg *msg) 71{ 72 struct sk_buff *skb; 73 74 if (test_bit(ATM_VF_RELEASED,&vcc->flags) || 75 !test_bit(ATM_VF_READY,&vcc->flags)) 76 return; 77 msg->type = as_error; 78 if (!vcc->dev->ops->change_qos) msg->reply = -EOPNOTSUPP; 79 else { 80 /* should lock VCC */ 81 msg->reply = vcc->dev->ops->change_qos(vcc,&msg->qos, 82 msg->reply); 83 if (!msg->reply) msg->type = as_okay; 84 } 85 /* 86 * Should probably just turn around the old skb. But the, the buffer 87 * space accounting needs to follow the change too. Maybe later. 88 */ 89 while (!(skb = alloc_skb(sizeof(struct atmsvc_msg),GFP_KERNEL))) 90 schedule(); 91 *(struct atmsvc_msg *) skb_put(skb,sizeof(struct atmsvc_msg)) = *msg; 92 sigd_put_skb(skb); 93} 94 95 96static int sigd_send(struct atm_vcc *vcc,struct sk_buff *skb) 97{ 98 struct atmsvc_msg *msg; 99 struct atm_vcc *session_vcc; 100 struct sock *sk; 101 102 msg = (struct atmsvc_msg *) skb->data; 103 atomic_sub(skb->truesize, &sk_atm(vcc)->sk_wmem_alloc); 104 DPRINTK("sigd_send %d (0x%lx)\n",(int) msg->type, 105 (unsigned long) msg->vcc); 106 vcc = *(struct atm_vcc **) &msg->vcc; 107 sk = sk_atm(vcc); 108 109 switch (msg->type) { 110 case as_okay: 111 sk->sk_err = -msg->reply; 112 clear_bit(ATM_VF_WAITING, &vcc->flags); 113 if (!*vcc->local.sas_addr.prv && 114 !*vcc->local.sas_addr.pub) { 115 vcc->local.sas_family = AF_ATMSVC; 116 memcpy(vcc->local.sas_addr.prv, 117 msg->local.sas_addr.prv,ATM_ESA_LEN); 118 memcpy(vcc->local.sas_addr.pub, 119 msg->local.sas_addr.pub,ATM_E164_LEN+1); 120 } 121 session_vcc = vcc->session ? vcc->session : vcc; 122 if (session_vcc->vpi || session_vcc->vci) break; 123 session_vcc->itf = msg->pvc.sap_addr.itf; 124 session_vcc->vpi = msg->pvc.sap_addr.vpi; 125 session_vcc->vci = msg->pvc.sap_addr.vci; 126 if (session_vcc->vpi || session_vcc->vci) 127 session_vcc->qos = msg->qos; 128 break; 129 case as_error: 130 clear_bit(ATM_VF_REGIS,&vcc->flags); 131 clear_bit(ATM_VF_READY,&vcc->flags); 132 sk->sk_err = -msg->reply; 133 clear_bit(ATM_VF_WAITING, &vcc->flags); 134 break; 135 case as_indicate: 136 vcc = *(struct atm_vcc **) &msg->listen_vcc; 137 sk = sk_atm(vcc); 138 DPRINTK("as_indicate!!!\n"); 139 lock_sock(sk); 140 if (sk_acceptq_is_full(sk)) { 141 sigd_enq(NULL,as_reject,vcc,NULL,NULL); 142 dev_kfree_skb(skb); 143 goto as_indicate_complete; 144 } 145 sk->sk_ack_backlog++; 146 skb_queue_tail(&sk->sk_receive_queue, skb); 147 DPRINTK("waking sk->sk_sleep 0x%p\n", sk->sk_sleep); 148 sk->sk_state_change(sk); 149as_indicate_complete: 150 release_sock(sk); 151 return 0; 152 case as_close: 153 set_bit(ATM_VF_RELEASED,&vcc->flags); 154 vcc_release_async(vcc, msg->reply); 155 goto out; 156 case as_modify: 157 modify_qos(vcc,msg); 158 break; 159 case as_addparty: 160 case as_dropparty: 161 sk->sk_err_soft = msg->reply; /* < 0 failure, otherwise ep_ref */ 162 clear_bit(ATM_VF_WAITING, &vcc->flags); 163 break; 164 default: 165 printk(KERN_ALERT "sigd_send: bad message type %d\n", 166 (int) msg->type); 167 return -EINVAL; 168 } 169 sk->sk_state_change(sk); 170out: 171 dev_kfree_skb(skb); 172 return 0; 173} 174 175 176void sigd_enq2(struct atm_vcc *vcc,enum atmsvc_msg_type type, 177 struct atm_vcc *listen_vcc,const struct sockaddr_atmpvc *pvc, 178 const struct sockaddr_atmsvc *svc,const struct atm_qos *qos,int reply) 179{ 180 struct sk_buff *skb; 181 struct atmsvc_msg *msg; 182 static unsigned session = 0; 183 184 DPRINTK("sigd_enq %d (0x%p)\n",(int) type,vcc); 185 while (!(skb = alloc_skb(sizeof(struct atmsvc_msg),GFP_KERNEL))) 186 schedule(); 187 msg = (struct atmsvc_msg *) skb_put(skb,sizeof(struct atmsvc_msg)); 188 memset(msg,0,sizeof(*msg)); 189 msg->type = type; 190 *(struct atm_vcc **) &msg->vcc = vcc; 191 *(struct atm_vcc **) &msg->listen_vcc = listen_vcc; 192 msg->reply = reply; 193 if (qos) msg->qos = *qos; 194 if (vcc) msg->sap = vcc->sap; 195 if (svc) msg->svc = *svc; 196 if (vcc) msg->local = vcc->local; 197 if (pvc) msg->pvc = *pvc; 198 if (vcc) { 199 if (type == as_connect && test_bit(ATM_VF_SESSION, &vcc->flags)) 200 msg->session = ++session; 201 /* every new pmp connect gets the next session number */ 202 } 203 sigd_put_skb(skb); 204 if (vcc) set_bit(ATM_VF_REGIS,&vcc->flags); 205} 206 207 208void sigd_enq(struct atm_vcc *vcc,enum atmsvc_msg_type type, 209 struct atm_vcc *listen_vcc,const struct sockaddr_atmpvc *pvc, 210 const struct sockaddr_atmsvc *svc) 211{ 212 sigd_enq2(vcc,type,listen_vcc,pvc,svc,vcc ? &vcc->qos : NULL,0); 213 /* other ISP applications may use "reply" */ 214} 215 216 217static void purge_vcc(struct atm_vcc *vcc) 218{ 219 if (sk_atm(vcc)->sk_family == PF_ATMSVC && 220 !test_bit(ATM_VF_META,&vcc->flags)) { 221 set_bit(ATM_VF_RELEASED,&vcc->flags); 222 vcc_release_async(vcc, -EUNATCH); 223 } 224} 225 226 227static void sigd_close(struct atm_vcc *vcc) 228{ 229 struct hlist_node *node; 230 struct sock *s; 231 int i; 232 233 DPRINTK("sigd_close\n"); 234 sigd = NULL; 235 if (skb_peek(&sk_atm(vcc)->sk_receive_queue)) 236 printk(KERN_ERR "sigd_close: closing with requests pending\n"); 237 skb_queue_purge(&sk_atm(vcc)->sk_receive_queue); 238 239 read_lock(&vcc_sklist_lock); 240 for(i = 0; i < VCC_HTABLE_SIZE; ++i) { 241 struct hlist_head *head = &vcc_hash[i]; 242 243 sk_for_each(s, node, head) { 244 struct atm_vcc *vcc = atm_sk(s); 245 246 if (vcc->dev) 247 purge_vcc(vcc); 248 } 249 } 250 read_unlock(&vcc_sklist_lock); 251} 252 253 254static struct atmdev_ops sigd_dev_ops = { 255 .close = sigd_close, 256 .send = sigd_send 257}; 258 259 260static struct atm_dev sigd_dev = { 261 .ops = &sigd_dev_ops, 262 .type = "sig", 263 .number = 999, 264 .lock = SPIN_LOCK_UNLOCKED 265}; 266 267 268int sigd_attach(struct atm_vcc *vcc) 269{ 270 if (sigd) return -EADDRINUSE; 271 DPRINTK("sigd_attach\n"); 272 sigd = vcc; 273 vcc->dev = &sigd_dev; 274 vcc_insert_socket(sk_atm(vcc)); 275 set_bit(ATM_VF_META,&vcc->flags); 276 set_bit(ATM_VF_READY,&vcc->flags); 277#ifdef WAIT_FOR_DEMON 278 wake_up(&sigd_sleep); 279#endif 280 return 0; 281} 282