[TCP]: Extract DSACK detection code from tcp_sacktag_write_queue().
[linux-2.6] / net / atm / ioctl.c
1 /* ATM ioctl handling */
2
3 /* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
4 /* 2003 John Levon  <levon@movementarian.org> */
5
6
7 #include <linux/module.h>
8 #include <linux/kmod.h>
9 #include <linux/net.h>          /* struct socket, struct proto_ops */
10 #include <linux/atm.h>          /* ATM stuff */
11 #include <linux/atmdev.h>
12 #include <linux/atmclip.h>      /* CLIP_*ENCAP */
13 #include <linux/atmarp.h>       /* manifest constants */
14 #include <linux/capability.h>
15 #include <linux/sonet.h>        /* for ioctls */
16 #include <linux/atmsvc.h>
17 #include <linux/atmmpc.h>
18 #include <net/atmclip.h>
19 #include <linux/atmlec.h>
20 #include <linux/mutex.h>
21 #include <asm/ioctls.h>
22
23 #include "resources.h"
24 #include "signaling.h"          /* for WAITING and sigd_attach */
25 #include "common.h"
26
27
28 static DEFINE_MUTEX(ioctl_mutex);
29 static LIST_HEAD(ioctl_list);
30
31
32 void register_atm_ioctl(struct atm_ioctl *ioctl)
33 {
34         mutex_lock(&ioctl_mutex);
35         list_add_tail(&ioctl->list, &ioctl_list);
36         mutex_unlock(&ioctl_mutex);
37 }
38
39 void deregister_atm_ioctl(struct atm_ioctl *ioctl)
40 {
41         mutex_lock(&ioctl_mutex);
42         list_del(&ioctl->list);
43         mutex_unlock(&ioctl_mutex);
44 }
45
46 EXPORT_SYMBOL(register_atm_ioctl);
47 EXPORT_SYMBOL(deregister_atm_ioctl);
48
49 int vcc_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
50 {
51         struct sock *sk = sock->sk;
52         struct atm_vcc *vcc;
53         int error;
54         struct list_head * pos;
55         void __user *argp = (void __user *)arg;
56
57         vcc = ATM_SD(sock);
58         switch (cmd) {
59                 case SIOCOUTQ:
60                         if (sock->state != SS_CONNECTED ||
61                             !test_bit(ATM_VF_READY, &vcc->flags)) {
62                                 error =  -EINVAL;
63                                 goto done;
64                         }
65                         error = put_user(sk->sk_sndbuf -
66                                          atomic_read(&sk->sk_wmem_alloc),
67                                          (int __user *) argp) ? -EFAULT : 0;
68                         goto done;
69                 case SIOCINQ:
70                         {
71                                 struct sk_buff *skb;
72
73                                 if (sock->state != SS_CONNECTED) {
74                                         error = -EINVAL;
75                                         goto done;
76                                 }
77                                 skb = skb_peek(&sk->sk_receive_queue);
78                                 error = put_user(skb ? skb->len : 0,
79                                                  (int __user *)argp) ? -EFAULT : 0;
80                                 goto done;
81                         }
82                 case SIOCGSTAMP: /* borrowed from IP */
83                         error = sock_get_timestamp(sk, argp);
84                         goto done;
85                 case SIOCGSTAMPNS: /* borrowed from IP */
86                         error = sock_get_timestampns(sk, argp);
87                         goto done;
88                 case ATM_SETSC:
89                         printk(KERN_WARNING "ATM_SETSC is obsolete\n");
90                         error = 0;
91                         goto done;
92                 case ATMSIGD_CTRL:
93                         if (!capable(CAP_NET_ADMIN)) {
94                                 error = -EPERM;
95                                 goto done;
96                         }
97                         /*
98                          * The user/kernel protocol for exchanging signalling
99                          * info uses kernel pointers as opaque references,
100                          * so the holder of the file descriptor can scribble
101                          * on the kernel... so we should make sure that we
102                          * have the same privledges that /proc/kcore needs
103                          */
104                         if (!capable(CAP_SYS_RAWIO)) {
105                                 error = -EPERM;
106                                 goto done;
107                         }
108                         error = sigd_attach(vcc);
109                         if (!error)
110                                 sock->state = SS_CONNECTED;
111                         goto done;
112                 case ATM_SETBACKEND:
113                 case ATM_NEWBACKENDIF:
114                         {
115                                 atm_backend_t backend;
116                                 error = get_user(backend, (atm_backend_t __user *) argp);
117                                 if (error)
118                                         goto done;
119                                 switch (backend) {
120                                         case ATM_BACKEND_PPP:
121                                                 request_module("pppoatm");
122                                                 break;
123                                         case ATM_BACKEND_BR2684:
124                                                 request_module("br2684");
125                                                 break;
126                                 }
127                         }
128                         break;
129                 case ATMMPC_CTRL:
130                 case ATMMPC_DATA:
131                         request_module("mpoa");
132                         break;
133                 case ATMARPD_CTRL:
134                         request_module("clip");
135                         break;
136                 case ATMLEC_CTRL:
137                         request_module("lec");
138                         break;
139         }
140
141         error = -ENOIOCTLCMD;
142
143         mutex_lock(&ioctl_mutex);
144         list_for_each(pos, &ioctl_list) {
145                 struct atm_ioctl * ic = list_entry(pos, struct atm_ioctl, list);
146                 if (try_module_get(ic->owner)) {
147                         error = ic->ioctl(sock, cmd, arg);
148                         module_put(ic->owner);
149                         if (error != -ENOIOCTLCMD)
150                                 break;
151                 }
152         }
153         mutex_unlock(&ioctl_mutex);
154
155         if (error != -ENOIOCTLCMD)
156                 goto done;
157
158         error = atm_dev_ioctl(cmd, argp);
159
160 done:
161         return error;
162 }