fs/9p/trans_sock.c

   1 /*
   2  * linux/fs/9p/trans_socket.c
   3  *
   4  * Socket Transport Layer
   5  *
   6  *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
   7  *  Copyright (C) 1997-2002 by Ron Minnich <rminnich@sarnoff.com>
   8  *  Copyright (C) 1995, 1996 by Olaf Kirch <okir@monad.swb.de>
   9  *
  10  *  This program is free software; you can redistribute it and/or modify
  11  *  it under the terms of the GNU General Public License as published by
  12  *  the Free Software Foundation; either version 2 of the License, or
  13  *  (at your option) any later version.
  14  *
  15  *  This program is distributed in the hope that it will be useful,
  16  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  *  GNU General Public License for more details.
  19  *
  20  *  You should have received a copy of the GNU General Public License
  21  *  along with this program; if not, write to:
  22  *  Free Software Foundation
  23  *  51 Franklin Street, Fifth Floor
  24  *  Boston, MA  02111-1301  USA
  25  *
  26  */
  27
  28 #include <linux/config.h>
  29 #include <linux/in.h>
  30 #include <linux/module.h>
  31 #include <linux/net.h>
  32 #include <linux/ipv6.h>
  33 #include <linux/errno.h>
  34 #include <linux/kernel.h>
  35 #include <linux/un.h>
  36 #include <asm/uaccess.h>
  37 #include <linux/inet.h>
  38 #include <linux/idr.h>
  39
  40 #include "debug.h"
  41 #include "v9fs.h"
  42 #include "transport.h"
  43
  44 #define V9FS_PORT 564
  45
  46 struct v9fs_trans_sock {
  47         struct socket *s;
  48 };
  49
  50 /**
  51  * v9fs_sock_recv - receive from a socket
  52  * @v9ses: session information
  53  * @v: buffer to receive data into
  54  * @len: size of receive buffer
  55  *
  56  */
  57
  58 static int v9fs_sock_recv(struct v9fs_transport *trans, void *v, int len)
  59 {
  60         struct msghdr msg;
  61         struct kvec iov;
  62         int result;
  63         mm_segment_t oldfs;
  64         struct v9fs_trans_sock *ts = trans ? trans->priv : NULL;
  65
  66         if (trans->status == Disconnected)
  67                 return -EREMOTEIO;
  68
  69         result = -EINVAL;
  70
  71         oldfs = get_fs();
  72         set_fs(get_ds());
  73
  74         iov.iov_base = v;
  75         iov.iov_len = len;
  76         msg.msg_name = NULL;
  77         msg.msg_namelen = 0;
  78         msg.msg_iovlen = 1;
  79         msg.msg_control = NULL;
  80         msg.msg_controllen = 0;
  81         msg.msg_namelen = 0;
  82         msg.msg_flags = MSG_NOSIGNAL;
  83
  84         result = kernel_recvmsg(ts->s, &msg, &iov, 1, len, 0);
  85
  86         dprintk(DEBUG_TRANS, "socket state %d\n", ts->s->state);
  87         set_fs(oldfs);
  88
  89         if (result <= 0) {
  90                 if (result != -ERESTARTSYS)
  91                         trans->status = Disconnected;
  92         }
  93
  94         return result;
  95 }
  96
  97 /**
  98  * v9fs_sock_send - send to a socket
  99  * @v9ses: session information
 100  * @v: buffer to send data from
 101  * @len: size of send buffer
 102  *
 103  */
 104
 105 static int v9fs_sock_send(struct v9fs_transport *trans, void *v, int len)
 106 {
 107         struct kvec iov;
 108         struct msghdr msg;
 109         int result = -1;
 110         mm_segment_t oldfs;
 111         struct v9fs_trans_sock *ts = trans ? trans->priv : NULL;
 112
 113         dprintk(DEBUG_TRANS, "Sending packet size %d (%x)\n", len, len);
 114         dump_data(v, len);
 115
 116         down(&trans->writelock);
 117
 118         oldfs = get_fs();
 119         set_fs(get_ds());
 120         iov.iov_base = v;
 121         iov.iov_len = len;
 122         msg.msg_name = NULL;
 123         msg.msg_namelen = 0;
 124         msg.msg_iovlen = 1;
 125         msg.msg_control = NULL;
 126         msg.msg_controllen = 0;
 127         msg.msg_namelen = 0;
 128         msg.msg_flags = MSG_NOSIGNAL;
 129         result = kernel_sendmsg(ts->s, &msg, &iov, 1, len);
 130         set_fs(oldfs);
 131
 132         if (result < 0) {
 133                 if (result != -ERESTARTSYS)
 134                         trans->status = Disconnected;
 135         }
 136
 137         up(&trans->writelock);
 138         return result;
 139 }
 140
 141 /**
 142  * v9fs_tcp_init - initialize TCP socket
 143  * @v9ses: session information
 144  * @addr: address of server to mount
 145  * @data: mount options
 146  *
 147  */
 148
 149 static int
 150 v9fs_tcp_init(struct v9fs_session_info *v9ses, const char *addr, char *data)
 151 {
 152         struct socket *csocket = NULL;
 153         struct sockaddr_in sin_server;
 154         int rc = 0;
 155         struct v9fs_trans_sock *ts = NULL;
 156         struct v9fs_transport *trans = v9ses->transport;
 157
 158         sema_init(&trans->writelock, 1);
 159         sema_init(&trans->readlock, 1);
 160
 161         ts = kmalloc(sizeof(struct v9fs_trans_sock), GFP_KERNEL);
 162
 163         if (!ts)
 164                 return -ENOMEM;
 165
 166         trans->priv = ts;
 167         ts->s = NULL;
 168
 169         if (!addr)
 170                 return -EINVAL;
 171
 172         dprintk(DEBUG_TRANS, "Connecting to %s\n", addr);
 173
 174         sin_server.sin_family = AF_INET;
 175         sin_server.sin_addr.s_addr = in_aton(addr);
 176         sin_server.sin_port = htons(v9ses->port);
 177         sock_create_kern(PF_INET, SOCK_STREAM, IPPROTO_TCP, &csocket);
 178         rc = csocket->ops->connect(csocket,
 179                                    (struct sockaddr *)&sin_server,
 180                                    sizeof(struct sockaddr_in), 0);
 181         if (rc < 0) {
 182                 eprintk(KERN_ERR,
 183                         "v9fs_trans_tcp: problem connecting socket to %s\n",
 184                         addr);
 185                 return rc;
 186         }
 187         csocket->sk->sk_allocation = GFP_NOIO;
 188         ts->s = csocket;
 189         trans->status = Connected;
 190
 191         return 0;
 192 }
 193
 194 /**
 195  * v9fs_unix_init - initialize UNIX domain socket
 196  * @v9ses: session information
 197  * @dev_name: path to named pipe
 198  * @data: mount options
 199  *
 200  */
 201
 202 static int
 203 v9fs_unix_init(struct v9fs_session_info *v9ses, const char *dev_name,
 204                char *data)
 205 {
 206         int rc;
 207         struct socket *csocket;
 208         struct sockaddr_un sun_server;
 209         struct v9fs_transport *trans;
 210         struct v9fs_trans_sock *ts;
 211
 212         rc = 0;
 213         csocket = NULL;
 214         trans = v9ses->transport;
 215
 216         if (strlen(dev_name) > UNIX_PATH_MAX) {
 217                 eprintk(KERN_ERR, "v9fs_trans_unix: address too long: %s\n",
 218                         dev_name);
 219                 return -ENOMEM;
 220         }
 221
 222         ts = kmalloc(sizeof(struct v9fs_trans_sock), GFP_KERNEL);
 223         if (!ts)
 224                 return -ENOMEM;
 225
 226         trans->priv = ts;
 227         ts->s = NULL;
 228
 229         sema_init(&trans->writelock, 1);
 230         sema_init(&trans->readlock, 1);
 231
 232         sun_server.sun_family = PF_UNIX;
 233         strcpy(sun_server.sun_path, dev_name);
 234         sock_create_kern(PF_UNIX, SOCK_STREAM, 0, &csocket);
 235         rc = csocket->ops->connect(csocket, (struct sockaddr *)&sun_server,
 236                 sizeof(struct sockaddr_un) - 1, 0);     /* -1 *is* important */
 237         if (rc < 0) {
 238                 eprintk(KERN_ERR,
 239                         "v9fs_trans_unix: problem connecting socket: %s: %d\n",
 240                         dev_name, rc);
 241                 return rc;
 242         }
 243         csocket->sk->sk_allocation = GFP_NOIO;
 244         ts->s = csocket;
 245         trans->status = Connected;
 246
 247         return 0;
 248 }
 249
 250 /**
 251  * v9fs_sock_close - shutdown socket
 252  * @trans: private socket structure
 253  *
 254  */
 255
 256 static void v9fs_sock_close(struct v9fs_transport *trans)
 257 {
 258         struct v9fs_trans_sock *ts;
 259
 260         if (!trans)
 261                 return;
 262
 263         ts = trans->priv;
 264
 265         if ((ts) && (ts->s)) {
 266                 dprintk(DEBUG_TRANS, "closing the socket %p\n", ts->s);
 267                 sock_release(ts->s);
 268                 ts->s = NULL;
 269                 trans->status = Disconnected;
 270                 dprintk(DEBUG_TRANS, "socket closed\n");
 271         }
 272
 273         kfree(ts);
 274
 275         trans->priv = NULL;
 276 }
 277
 278 struct v9fs_transport v9fs_trans_tcp = {
 279         .init = v9fs_tcp_init,
 280         .write = v9fs_sock_send,
 281         .read = v9fs_sock_recv,
 282         .close = v9fs_sock_close,
 283 };
 284
 285 struct v9fs_transport v9fs_trans_unix = {
 286         .init = v9fs_unix_init,
 287         .write = v9fs_sock_send,
 288         .read = v9fs_sock_recv,
 289         .close = v9fs_sock_close,
 290 };