net/cor/sock.c

   1 /*
   2  *      Connection oriented routing
   3  *      Copyright (C) 2007-2008 Michael Blizek
   4  *
   5  *      This program is free software; you can redistribute it and/or
   6  *      modify it under the terms of the GNU General Public License
   7  *      as published by the Free Software Foundation; either version 2
   8  *      of the License, or (at your option) any later version.
   9  *
  10  *      This program is distributed in the hope that it will be useful,
  11  *      but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *      GNU General Public License for more details.
  14  *
  15  *      You should have received a copy of the GNU General Public License
  16  *      along with this program; if not, write to the Free Software
  17  *      Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  18  *      02110-1301, USA.
  19  */
  20
  21 #include <net/sock.h>
  22 #include <linux/net.h>
  23 #include <asm/uaccess.h>
  24
  25 #include "cor.h"
  26
  27 static int check_connlistener_state(struct connlistener *cl)
  28 {
  29         if (likely(cl != 0 && cl->sockstate == SOCKSTATE_LISTENER))
  30                 return 0;
  31
  32         return 1;
  33 }
  34
  35 static int check_conn_state(struct conn *conn)
  36 {
  37         if (likely(conn != 0 && conn->sockstate == SOCKSTATE_CONN))
  38                 return 0;
  39
  40         return 1;
  41 }
  42
  43 int cor_socket_release(struct socket *sock)
  44 {
  45         struct connlistener *cl = (struct connlistener *) sock->sk;
  46         struct conn *rconn = (struct conn *) sock->sk;
  47
  48         if (sock->sk == 0)
  49                 return 0;
  50
  51         if (cl->sockstate == SOCKSTATE_LISTENER) {
  52                 close_port(cl);
  53         } else if (rconn->sockstate == SOCKSTATE_CONN) {
  54                 reset_conn(rconn);
  55                 kref_put(&(rconn->ref), free_conn);
  56         } else {
  57                 BUG();
  58         }
  59
  60         return 0;
  61 }
  62
  63 int cor_socket_bind(struct socket *sock, struct sockaddr *myaddr,
  64                 int sockaddr_len)
  65 {
  66         struct connlistener *listener;
  67         struct cor_sockaddr *addr = (struct cor_sockaddr *) myaddr;
  68
  69         if (unlikely(sock->sk != 0))
  70                 return -EINVAL;
  71
  72         if (sockaddr_len < sizeof(struct cor_sockaddr))
  73                 return -EINVAL;
  74
  75         if (addr->type != SOCKADDRTYPE_PORT)
  76                 return -EINVAL;
  77
  78         listener = open_port(addr->addr.port);
  79
  80         if (listener == 0)
  81                 return -EADDRINUSE;
  82
  83         sock->sk = (struct sock *) listener;
  84
  85         return 0;
  86 }
  87
  88 int cor_socket_connect(struct socket *sock, struct sockaddr *vaddr,
  89                 int sockaddr_len, int flags)
  90 {
  91         struct conn *rconn;
  92
  93         if (unlikely(sock->sk != 0))
  94                 return -EISCONN;
  95
  96         rconn = alloc_conn(GFP_KERNEL);
  97
  98         kref_get(&(rconn->ref));
  99
 100         if (unlikely(rconn == 0))
 101                 return -ENOMEM;
 102
 103         conn_init_sock_source(rconn);
 104         conn_init_sock_target(rconn->reversedir);
 105
 106         sock->sk = (struct sock *) rconn;
 107         sock->state = SS_CONNECTED;
 108
 109         return 0;
 110 }
 111
 112 static int cor_rdytoaccept(struct connlistener *cl)
 113 {
 114         int rc;
 115         mutex_lock(&(cl->lock));
 116         rc = (list_empty(&(cl->conn_queue)) == 0);
 117         mutex_unlock(&(cl->lock));
 118         return rc;
 119 }
 120
 121 const struct proto_ops cor_proto_ops;
 122
 123 int cor_socket_accept(struct socket *sock, struct socket *newsock, int flags)
 124 {
 125         struct connlistener *cl = (struct connlistener *) sock->sk;
 126
 127         int rc = check_connlistener_state(cl);
 128
 129         struct conn *newconn;
 130
 131         if (unlikely(rc))
 132                 return -EINVAL;
 133
 134         mutex_lock(&(cl->lock));
 135
 136         if (unlikely(cl->queue_maxlen <= 0)) {
 137                 mutex_unlock(&(cl->lock));
 138                 return -EINVAL;
 139         }
 140
 141         while (list_empty(&(cl->conn_queue))) {
 142                 mutex_unlock(&(cl->lock));
 143                 if (wait_event_interruptible(cl->wait, cor_rdytoaccept(cl))) {
 144                         return -ERESTARTSYS;
 145                 }
 146                 mutex_lock(&(cl->lock));
 147         }
 148
 149         newconn = container_of(cl->conn_queue.next, struct conn,
 150                         source.sock.cl_list);
 151
 152         BUG_ON(newconn->sourcetype != SOURCE_SOCK);
 153
 154         list_del(cl->conn_queue.next);
 155
 156         cl->queue_len--;
 157
 158         mutex_unlock(&(cl->lock));
 159
 160         newsock->ops = &cor_proto_ops;
 161         newsock->sk = (struct sock *) newconn;
 162         newsock->state = SS_CONNECTED;
 163
 164         return 0;
 165 }
 166
 167 int cor_socket_listen(struct socket *sock, int len)
 168 {
 169         struct connlistener *cl = (struct connlistener *) sock->sk;
 170
 171         int rc = check_connlistener_state(cl);
 172
 173         if (unlikely(rc))
 174                 return -EOPNOTSUPP;
 175
 176         mutex_lock(&(cl->lock));
 177         cl->queue_maxlen = len;
 178         mutex_unlock(&(cl->lock));
 179
 180         return 0;
 181 }
 182
 183 int cor_socket_shutdown(struct socket *sock, int flags)
 184 {
 185         return -ENOTSUPP;
 186 }
 187
 188 int cor_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 189 {
 190         return -ENOIOCTLCMD;
 191 }
 192
 193 static int sendmsg_maypush(struct conn *rconn)
 194 {
 195         int ret;
 196         mutex_lock(&(rconn->rcv_lock));
 197         ret = (databuf_maypush(&(rconn->buf)) != 0) ||
 198                         unlikely(atomic_read(&(rconn->isreset)) != 0);
 199         mutex_unlock(&(rconn->rcv_lock));
 200         return ret;
 201 }
 202
 203 int cor_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
 204                 size_t total_len)
 205 {
 206         int copied = 0;
 207
 208         struct conn *rconn = (struct conn *) sock->sk;
 209
 210         int rc = check_conn_state(rconn);
 211
 212         int blocking = (msg->msg_flags & MSG_DONTWAIT) == 0;
 213
 214         if (unlikely(rc))
 215                 return -EBADF;
 216
 217 recv:
 218         mutex_lock(&(rconn->rcv_lock));
 219
 220         if (unlikely(atomic_read(&(rconn->isreset)) != 0)) {
 221                 copied = -EPIPE;
 222                 goto out;
 223         }
 224
 225         copied = receive_userbuf(rconn, msg);
 226
 227 out:
 228         mutex_unlock(&(rconn->rcv_lock));
 229
 230         if (copied == -EAGAIN && blocking) {
 231                 if (wait_event_interruptible(rconn->source.sock.wait,
 232                                 sendmsg_maypush(rconn) == 0))
 233                         goto recv;
 234                 copied = -ERESTARTSYS;
 235         }
 236
 237         return copied;
 238 }
 239
 240 static int cor_readytoread(struct conn *sconn)
 241 {
 242         int rc = 0;
 243         mutex_lock(&(sconn->rcv_lock));
 244         rc = (sconn->buf.read_remaining != 0) ||
 245                         unlikely(atomic_read(&(sconn->isreset)) != 0);
 246         mutex_unlock(&(sconn->rcv_lock));
 247         return rc;
 248 }
 249
 250 int cor_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg,
 251                 size_t total_len, int flags)
 252 {
 253         struct conn *rconn = (struct conn *) sock->sk;
 254         struct conn *sconn = rconn->reversedir;
 255         size_t copied = 0;
 256
 257         int rc = check_conn_state(rconn);
 258
 259         int blocking = (flags & MSG_DONTWAIT) == 0;
 260
 261         if (unlikely(rc))
 262                 return -EBADF;
 263
 264         BUG_ON(sconn == 0);
 265
 266 recv:
 267         mutex_lock(&(sconn->rcv_lock));
 268
 269         if (unlikely(atomic_read(&(rconn->isreset)) != 0)) {
 270                 copied = -EPIPE;
 271                 goto out;
 272         }
 273
 274         copied = databuf_pulluser(sconn, msg);
 275         databuf_ackread(&(sconn->buf));
 276         wake_sender(sconn);
 277
 278 out:
 279         mutex_unlock(&(sconn->rcv_lock));
 280
 281         if (copied == -EAGAIN && blocking) {
 282                 if (wait_event_interruptible(sconn->target.sock.wait,
 283                                 cor_readytoread(sconn)) == 0)
 284                         goto recv;
 285                 copied = -ERESTARTSYS;
 286         }
 287
 288         return copied;
 289 }
 290
 291 const struct proto_ops cor_proto_ops = {
 292                 .family = PF_COR,
 293                 .owner = THIS_MODULE,
 294                 .release = cor_socket_release,
 295                 .bind = cor_socket_bind,
 296                 .connect = cor_socket_connect,
 297                 .accept = cor_socket_accept,
 298                 .listen = cor_socket_listen,
 299                 .shutdown = cor_socket_shutdown,
 300                 .ioctl = cor_ioctl,
 301                 .sendmsg = cor_sendmsg,
 302                 .recvmsg = cor_recvmsg
 303
 304         /*socketpair
 305         getname
 306         poll
 307         compat_ioctl
 308         setsockopt
 309         getsockopt
 310         compat_setsockopt
 311         compat_getsockopt
 312         mmap
 313         sendpage
 314         splice_read*/
 315 };
 316
 317 int cor_createsock(struct net *net, struct socket *sock, int protocol)
 318 {
 319         if (unlikely(protocol != 0))
 320                 return -EPROTONOSUPPORT;
 321
 322         sock->state = SS_UNCONNECTED;
 323         sock->ops = &cor_proto_ops;
 324
 325         return 0;
 326 }
 327
 328 static struct net_proto_family cor_net_proto_family = {
 329         .family = PF_COR,
 330         .create = cor_createsock,
 331         .owner = THIS_MODULE
 332 };
 333
 334 static int __init cor_sock_init(void)
 335 {
 336         sock_register(&cor_net_proto_family);
 337         return 0;
 338 }
 339
 340 module_init(cor_sock_init);
 341
 342 MODULE_LICENSE("GPL");
 343