clip: convert to internal network_device_stats
[linux-2.6.git] / net / atm / signaling.c
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 struct atm_vcc *sigd = NULL;
27 #ifdef WAIT_FOR_DEMON
28 static DECLARE_WAIT_QUEUE_HEAD(sigd_sleep);
29 #endif
30
31
32 static void sigd_put_skb(struct sk_buff *skb)
33 {
34 #ifdef WAIT_FOR_DEMON
35         DECLARE_WAITQUEUE(wait,current);
36
37         add_wait_queue(&sigd_sleep,&wait);
38         while (!sigd) {
39                 set_current_state(TASK_UNINTERRUPTIBLE);
40                 pr_debug("atmsvc: waiting for signaling demon...\n");
41                 schedule();
42         }
43         current->state = TASK_RUNNING;
44         remove_wait_queue(&sigd_sleep,&wait);
45 #else
46         if (!sigd) {
47                 pr_debug("atmsvc: no signaling demon\n");
48                 kfree_skb(skb);
49                 return;
50         }
51 #endif
52         atm_force_charge(sigd,skb->truesize);
53         skb_queue_tail(&sk_atm(sigd)->sk_receive_queue,skb);
54         sk_atm(sigd)->sk_data_ready(sk_atm(sigd), skb->len);
55 }
56
57
58 static void modify_qos(struct atm_vcc *vcc,struct atmsvc_msg *msg)
59 {
60         struct sk_buff *skb;
61
62         if (test_bit(ATM_VF_RELEASED,&vcc->flags) ||
63             !test_bit(ATM_VF_READY,&vcc->flags))
64                 return;
65         msg->type = as_error;
66         if (!vcc->dev->ops->change_qos) msg->reply = -EOPNOTSUPP;
67         else {
68                 /* should lock VCC */
69                 msg->reply = vcc->dev->ops->change_qos(vcc,&msg->qos,
70                     msg->reply);
71                 if (!msg->reply) msg->type = as_okay;
72         }
73         /*
74          * Should probably just turn around the old skb. But the, the buffer
75          * space accounting needs to follow the change too. Maybe later.
76          */
77         while (!(skb = alloc_skb(sizeof(struct atmsvc_msg),GFP_KERNEL)))
78                 schedule();
79         *(struct atmsvc_msg *) skb_put(skb,sizeof(struct atmsvc_msg)) = *msg;
80         sigd_put_skb(skb);
81 }
82
83
84 static int sigd_send(struct atm_vcc *vcc,struct sk_buff *skb)
85 {
86         struct atmsvc_msg *msg;
87         struct atm_vcc *session_vcc;
88         struct sock *sk;
89
90         msg = (struct atmsvc_msg *) skb->data;
91         atomic_sub(skb->truesize, &sk_atm(vcc)->sk_wmem_alloc);
92         vcc = *(struct atm_vcc **) &msg->vcc;
93         pr_debug("sigd_send %d (0x%lx)\n",(int) msg->type,
94           (unsigned long) vcc);
95         sk = sk_atm(vcc);
96
97         switch (msg->type) {
98                 case as_okay:
99                         sk->sk_err = -msg->reply;
100                         clear_bit(ATM_VF_WAITING, &vcc->flags);
101                         if (!*vcc->local.sas_addr.prv &&
102                             !*vcc->local.sas_addr.pub) {
103                                 vcc->local.sas_family = AF_ATMSVC;
104                                 memcpy(vcc->local.sas_addr.prv,
105                                     msg->local.sas_addr.prv,ATM_ESA_LEN);
106                                 memcpy(vcc->local.sas_addr.pub,
107                                     msg->local.sas_addr.pub,ATM_E164_LEN+1);
108                         }
109                         session_vcc = vcc->session ? vcc->session : vcc;
110                         if (session_vcc->vpi || session_vcc->vci) break;
111                         session_vcc->itf = msg->pvc.sap_addr.itf;
112                         session_vcc->vpi = msg->pvc.sap_addr.vpi;
113                         session_vcc->vci = msg->pvc.sap_addr.vci;
114                         if (session_vcc->vpi || session_vcc->vci)
115                                 session_vcc->qos = msg->qos;
116                         break;
117                 case as_error:
118                         clear_bit(ATM_VF_REGIS,&vcc->flags);
119                         clear_bit(ATM_VF_READY,&vcc->flags);
120                         sk->sk_err = -msg->reply;
121                         clear_bit(ATM_VF_WAITING, &vcc->flags);
122                         break;
123                 case as_indicate:
124                         vcc = *(struct atm_vcc **) &msg->listen_vcc;
125                         sk = sk_atm(vcc);
126                         pr_debug("as_indicate!!!\n");
127                         lock_sock(sk);
128                         if (sk_acceptq_is_full(sk)) {
129                                 sigd_enq(NULL,as_reject,vcc,NULL,NULL);
130                                 dev_kfree_skb(skb);
131                                 goto as_indicate_complete;
132                         }
133                         sk->sk_ack_backlog++;
134                         skb_queue_tail(&sk->sk_receive_queue, skb);
135                         pr_debug("waking sk->sk_sleep 0x%p\n", sk->sk_sleep);
136                         sk->sk_state_change(sk);
137 as_indicate_complete:
138                         release_sock(sk);
139                         return 0;
140                 case as_close:
141                         set_bit(ATM_VF_RELEASED,&vcc->flags);
142                         vcc_release_async(vcc, msg->reply);
143                         goto out;
144                 case as_modify:
145                         modify_qos(vcc,msg);
146                         break;
147                 case as_addparty:
148                 case as_dropparty:
149                         sk->sk_err_soft = msg->reply;   /* < 0 failure, otherwise ep_ref */
150                         clear_bit(ATM_VF_WAITING, &vcc->flags);
151                         break;
152                 default:
153                         printk(KERN_ALERT "sigd_send: bad message type %d\n",
154                             (int) msg->type);
155                         return -EINVAL;
156         }
157         sk->sk_state_change(sk);
158 out:
159         dev_kfree_skb(skb);
160         return 0;
161 }
162
163
164 void sigd_enq2(struct atm_vcc *vcc,enum atmsvc_msg_type type,
165     struct atm_vcc *listen_vcc,const struct sockaddr_atmpvc *pvc,
166     const struct sockaddr_atmsvc *svc,const struct atm_qos *qos,int reply)
167 {
168         struct sk_buff *skb;
169         struct atmsvc_msg *msg;
170         static unsigned session = 0;
171
172         pr_debug("sigd_enq %d (0x%p)\n",(int) type,vcc);
173         while (!(skb = alloc_skb(sizeof(struct atmsvc_msg),GFP_KERNEL)))
174                 schedule();
175         msg = (struct atmsvc_msg *) skb_put(skb,sizeof(struct atmsvc_msg));
176         memset(msg,0,sizeof(*msg));
177         msg->type = type;
178         *(struct atm_vcc **) &msg->vcc = vcc;
179         *(struct atm_vcc **) &msg->listen_vcc = listen_vcc;
180         msg->reply = reply;
181         if (qos) msg->qos = *qos;
182         if (vcc) msg->sap = vcc->sap;
183         if (svc) msg->svc = *svc;
184         if (vcc) msg->local = vcc->local;
185         if (pvc) msg->pvc = *pvc;
186         if (vcc) {
187                 if (type == as_connect && test_bit(ATM_VF_SESSION, &vcc->flags))
188                         msg->session = ++session;
189                         /* every new pmp connect gets the next session number */
190         }
191         sigd_put_skb(skb);
192         if (vcc) set_bit(ATM_VF_REGIS,&vcc->flags);
193 }
194
195
196 void sigd_enq(struct atm_vcc *vcc,enum atmsvc_msg_type type,
197     struct atm_vcc *listen_vcc,const struct sockaddr_atmpvc *pvc,
198     const struct sockaddr_atmsvc *svc)
199 {
200         sigd_enq2(vcc,type,listen_vcc,pvc,svc,vcc ? &vcc->qos : NULL,0);
201         /* other ISP applications may use "reply" */
202 }
203
204
205 static void purge_vcc(struct atm_vcc *vcc)
206 {
207         if (sk_atm(vcc)->sk_family == PF_ATMSVC &&
208             !test_bit(ATM_VF_META, &vcc->flags)) {
209                 set_bit(ATM_VF_RELEASED, &vcc->flags);
210                 clear_bit(ATM_VF_REGIS, &vcc->flags);
211                 vcc_release_async(vcc, -EUNATCH);
212         }
213 }
214
215
216 static void sigd_close(struct atm_vcc *vcc)
217 {
218         struct hlist_node *node;
219         struct sock *s;
220         int i;
221
222         pr_debug("sigd_close\n");
223         sigd = NULL;
224         if (skb_peek(&sk_atm(vcc)->sk_receive_queue))
225                 printk(KERN_ERR "sigd_close: closing with requests pending\n");
226         skb_queue_purge(&sk_atm(vcc)->sk_receive_queue);
227
228         read_lock(&vcc_sklist_lock);
229         for(i = 0; i < VCC_HTABLE_SIZE; ++i) {
230                 struct hlist_head *head = &vcc_hash[i];
231
232                 sk_for_each(s, node, head) {
233                         vcc = atm_sk(s);
234
235                         purge_vcc(vcc);
236                 }
237         }
238         read_unlock(&vcc_sklist_lock);
239 }
240
241
242 static struct atmdev_ops sigd_dev_ops = {
243         .close = sigd_close,
244         .send = sigd_send
245 };
246
247
248 static struct atm_dev sigd_dev = {
249         .ops =          &sigd_dev_ops,
250         .type =         "sig",
251         .number =       999,
252         .lock =         __SPIN_LOCK_UNLOCKED(sigd_dev.lock)
253 };
254
255
256 int sigd_attach(struct atm_vcc *vcc)
257 {
258         if (sigd) return -EADDRINUSE;
259         pr_debug("sigd_attach\n");
260         sigd = vcc;
261         vcc->dev = &sigd_dev;
262         vcc_insert_socket(sk_atm(vcc));
263         set_bit(ATM_VF_META,&vcc->flags);
264         set_bit(ATM_VF_READY,&vcc->flags);
265 #ifdef WAIT_FOR_DEMON
266         wake_up(&sigd_sleep);
267 #endif
268         return 0;
269 }