fs/9p/trans_sock.c

   1 /*
   2  * linux/fs/9p/trans_socket.c
   3  *
   4  * Socket Transport Layer
   5  *
   6  *  Copyright (C) 2004-2005 by Latchesar Ionkov <lucho@ionkov.net>
   7  *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
   8  *  Copyright (C) 1997-2002 by Ron Minnich <rminnich@sarnoff.com>
   9  *  Copyright (C) 1995, 1996 by Olaf Kirch <okir@monad.swb.de>
  10  *
  11  *  This program is free software; you can redistribute it and/or modify
  12  *  it under the terms of the GNU General Public License as published by
  13  *  the Free Software Foundation; either version 2 of the License, or
  14  *  (at your option) any later version.
  15  *
  16  *  This program is distributed in the hope that it will be useful,
  17  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  *  GNU General Public License for more details.
  20  *
  21  *  You should have received a copy of the GNU General Public License
  22  *  along with this program; if not, write to:
  23  *  Free Software Foundation
  24  *  51 Franklin Street, Fifth Floor
  25  *  Boston, MA  02111-1301  USA
  26  *
  27  */
  28
  29 #include <linux/config.h>
  30 #include <linux/in.h>
  31 #include <linux/module.h>
  32 #include <linux/net.h>
  33 #include <linux/ipv6.h>
  34 #include <linux/errno.h>
  35 #include <linux/kernel.h>
  36 #include <linux/un.h>
  37 #include <asm/uaccess.h>
  38 #include <linux/inet.h>
  39 #include <linux/idr.h>
  40 #include <linux/file.h>
  41
  42 #include "debug.h"
  43 #include "v9fs.h"
  44 #include "transport.h"
  45
  46 #define V9FS_PORT 564
  47
  48 struct v9fs_trans_sock {
  49         struct socket *s;
  50         struct file *filp;
  51 };
  52
  53 /**
  54  * v9fs_sock_recv - receive from a socket
  55  * @v9ses: session information
  56  * @v: buffer to receive data into
  57  * @len: size of receive buffer
  58  *
  59  */
  60
  61 static int v9fs_sock_recv(struct v9fs_transport *trans, void *v, int len)
  62 {
  63         int ret;
  64         struct v9fs_trans_sock *ts;
  65
  66         if (!trans || trans->status == Disconnected) {
  67                 dprintk(DEBUG_ERROR, "disconnected ...\n");
  68                 return -EREMOTEIO;
  69         }
  70
  71         ts = trans->priv;
  72
  73         if (!(ts->filp->f_flags & O_NONBLOCK))
  74                 dprintk(DEBUG_ERROR, "blocking read ...\n");
  75
  76         ret = kernel_read(ts->filp, ts->filp->f_pos, v, len);
  77         if (ret <= 0) {
  78                 if (ret != -ERESTARTSYS && ret != -EAGAIN)
  79                         trans->status = Disconnected;
  80         }
  81
  82         return ret;
  83 }
  84
  85 /**
  86  * v9fs_sock_send - send to a socket
  87  * @v9ses: session information
  88  * @v: buffer to send data from
  89  * @len: size of send buffer
  90  *
  91  */
  92
  93 static int v9fs_sock_send(struct v9fs_transport *trans, void *v, int len)
  94 {
  95         int ret;
  96         mm_segment_t oldfs;
  97         struct v9fs_trans_sock *ts;
  98
  99         if (!trans || trans->status == Disconnected) {
 100                 dprintk(DEBUG_ERROR, "disconnected ...\n");
 101                 return -EREMOTEIO;
 102         }
 103
 104         ts = trans->priv;
 105         if (!ts) {
 106                 dprintk(DEBUG_ERROR, "no transport ...\n");
 107                 return -EREMOTEIO;
 108         }
 109
 110         if (!(ts->filp->f_flags & O_NONBLOCK))
 111                 dprintk(DEBUG_ERROR, "blocking write ...\n");
 112
 113         dump_data(v, len);
 114         oldfs = get_fs();
 115         set_fs(get_ds());
 116         ret = vfs_write(ts->filp, (void __user *)v, len, &ts->filp->f_pos);
 117         set_fs(oldfs);
 118
 119         if (ret < 0) {
 120                 if (ret != -ERESTARTSYS)
 121                         trans->status = Disconnected;
 122         }
 123
 124         return ret;
 125 }
 126
 127 static unsigned int v9fs_sock_poll(struct v9fs_transport *trans,
 128         struct poll_table_struct *pt) {
 129
 130         int ret;
 131         struct v9fs_trans_sock *ts;
 132         mm_segment_t oldfs;
 133
 134         if (!trans) {
 135                 dprintk(DEBUG_ERROR, "no transport\n");
 136                 return -EIO;
 137         }
 138
 139         ts = trans->priv;
 140         if (trans->status != Connected || !ts) {
 141                 dprintk(DEBUG_ERROR, "transport disconnected: %d\n", trans->status);
 142                 return -EIO;
 143         }
 144
 145         oldfs = get_fs();
 146         set_fs(get_ds());
 147
 148         if (!ts->filp->f_op || !ts->filp->f_op->poll) {
 149                 dprintk(DEBUG_ERROR, "no poll operation\n");
 150                 ret = -EIO;
 151                 goto end;
 152         }
 153
 154         ret = ts->filp->f_op->poll(ts->filp, pt);
 155
 156 end:
 157         set_fs(oldfs);
 158         return ret;
 159 }
 160
 161
 162 /**
 163  * v9fs_tcp_init - initialize TCP socket
 164  * @v9ses: session information
 165  * @addr: address of server to mount
 166  * @data: mount options
 167  *
 168  */
 169
 170 static int
 171 v9fs_tcp_init(struct v9fs_session_info *v9ses, const char *addr, char *data)
 172 {
 173         struct socket *csocket = NULL;
 174         struct sockaddr_in sin_server;
 175         int rc = 0;
 176         struct v9fs_trans_sock *ts = NULL;
 177         struct v9fs_transport *trans = v9ses->transport;
 178         int fd;
 179
 180         trans->status = Disconnected;
 181
 182         ts = kmalloc(sizeof(struct v9fs_trans_sock), GFP_KERNEL);
 183
 184         if (!ts)
 185                 return -ENOMEM;
 186
 187         trans->priv = ts;
 188         ts->s = NULL;
 189         ts->filp = NULL;
 190
 191         if (!addr)
 192                 return -EINVAL;
 193
 194         dprintk(DEBUG_TRANS, "Connecting to %s\n", addr);
 195
 196         sin_server.sin_family = AF_INET;
 197         sin_server.sin_addr.s_addr = in_aton(addr);
 198         sin_server.sin_port = htons(v9ses->port);
 199         sock_create_kern(PF_INET, SOCK_STREAM, IPPROTO_TCP, &csocket);
 200         rc = csocket->ops->connect(csocket,
 201                                    (struct sockaddr *)&sin_server,
 202                                    sizeof(struct sockaddr_in), 0);
 203         if (rc < 0) {
 204                 eprintk(KERN_ERR,
 205                         "v9fs_trans_tcp: problem connecting socket to %s\n",
 206                         addr);
 207                 return rc;
 208         }
 209         csocket->sk->sk_allocation = GFP_NOIO;
 210
 211         fd = sock_map_fd(csocket);
 212         if (fd < 0) {
 213                 sock_release(csocket);
 214                 kfree(ts);
 215                 trans->priv = NULL;
 216                 return fd;
 217         }
 218
 219         ts->s = csocket;
 220         ts->filp = fget(fd);
 221         ts->filp->f_flags |= O_NONBLOCK;
 222         trans->status = Connected;
 223
 224         return 0;
 225 }
 226
 227 /**
 228  * v9fs_unix_init - initialize UNIX domain socket
 229  * @v9ses: session information
 230  * @dev_name: path to named pipe
 231  * @data: mount options
 232  *
 233  */
 234
 235 static int
 236 v9fs_unix_init(struct v9fs_session_info *v9ses, const char *dev_name,
 237                char *data)
 238 {
 239         int rc, fd;
 240         struct socket *csocket;
 241         struct sockaddr_un sun_server;
 242         struct v9fs_transport *trans;
 243         struct v9fs_trans_sock *ts;
 244
 245         rc = 0;
 246         csocket = NULL;
 247         trans = v9ses->transport;
 248
 249         trans->status = Disconnected;
 250
 251         if (strlen(dev_name) > UNIX_PATH_MAX) {
 252                 eprintk(KERN_ERR, "v9fs_trans_unix: address too long: %s\n",
 253                         dev_name);
 254                 return -ENOMEM;
 255         }
 256
 257         ts = kmalloc(sizeof(struct v9fs_trans_sock), GFP_KERNEL);
 258         if (!ts)
 259                 return -ENOMEM;
 260
 261         trans->priv = ts;
 262         ts->s = NULL;
 263         ts->filp = NULL;
 264
 265         sun_server.sun_family = PF_UNIX;
 266         strcpy(sun_server.sun_path, dev_name);
 267         sock_create_kern(PF_UNIX, SOCK_STREAM, 0, &csocket);
 268         rc = csocket->ops->connect(csocket, (struct sockaddr *)&sun_server,
 269                 sizeof(struct sockaddr_un) - 1, 0);     /* -1 *is* important */
 270         if (rc < 0) {
 271                 eprintk(KERN_ERR,
 272                         "v9fs_trans_unix: problem connecting socket: %s: %d\n",
 273                         dev_name, rc);
 274                 return rc;
 275         }
 276         csocket->sk->sk_allocation = GFP_NOIO;
 277
 278         fd = sock_map_fd(csocket);
 279         if (fd < 0) {
 280                 sock_release(csocket);
 281                 kfree(ts);
 282                 trans->priv = NULL;
 283                 return fd;
 284         }
 285
 286         ts->s = csocket;
 287         ts->filp = fget(fd);
 288         ts->filp->f_flags |= O_NONBLOCK;
 289         trans->status = Connected;
 290
 291         return 0;
 292 }
 293
 294 /**
 295  * v9fs_sock_close - shutdown socket
 296  * @trans: private socket structure
 297  *
 298  */
 299
 300 static void v9fs_sock_close(struct v9fs_transport *trans)
 301 {
 302         struct v9fs_trans_sock *ts;
 303
 304         if (!trans)
 305                 return;
 306
 307         ts = trans->priv;
 308
 309         if ((ts) && (ts->filp)) {
 310                 fput(ts->filp);
 311                 ts->filp = NULL;
 312                 ts->s = NULL;
 313                 trans->status = Disconnected;
 314         }
 315
 316         kfree(ts);
 317
 318         trans->priv = NULL;
 319 }
 320
 321 struct v9fs_transport v9fs_trans_tcp = {
 322         .init = v9fs_tcp_init,
 323         .write = v9fs_sock_send,
 324         .read = v9fs_sock_recv,
 325         .close = v9fs_sock_close,
 326         .poll = v9fs_sock_poll,
 327 };
 328
 329 struct v9fs_transport v9fs_trans_unix = {
 330         .init = v9fs_unix_init,
 331         .write = v9fs_sock_send,
 332         .read = v9fs_sock_recv,
 333         .close = v9fs_sock_close,
 334         .poll = v9fs_sock_poll,
 335 };