fs/9p/v9fs.c

   1 /*
   2  *  linux/fs/9p/v9fs.c
   3  *
   4  *  This file contains functions assisting in mapping VFS to 9P2000
   5  *
   6  *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
   7  *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
   8  *
   9  *  This program is free software; you can redistribute it and/or modify
  10  *  it under the terms of the GNU General Public License version 2
  11  *  as published by the Free Software Foundation.
  12  *
  13  *  This program is distributed in the hope that it will be useful,
  14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *  GNU General Public License for more details.
  17  *
  18  *  You should have received a copy of the GNU General Public License
  19  *  along with this program; if not, write to:
  20  *  Free Software Foundation
  21  *  51 Franklin Street, Fifth Floor
  22  *  Boston, MA  02111-1301  USA
  23  *
  24  */
  25
  26 #include <linux/module.h>
  27 #include <linux/errno.h>
  28 #include <linux/fs.h>
  29 #include <linux/sched.h>
  30 #include <linux/parser.h>
  31 #include <linux/idr.h>
  32 #include <net/9p/9p.h>
  33 #include <net/9p/transport.h>
  34 #include <net/9p/conn.h>
  35 #include <net/9p/client.h>
  36 #include "v9fs.h"
  37 #include "v9fs_vfs.h"
  38
  39 /*
  40   * Option Parsing (code inspired by NFS code)
  41   *
  42   */
  43
  44 enum {
  45         /* Options that take integer arguments */
  46         Opt_port, Opt_msize, Opt_uid, Opt_gid, Opt_afid,
  47         Opt_rfdno, Opt_wfdno,
  48         /* String options */
  49         Opt_uname, Opt_remotename,
  50         /* Options that take no arguments */
  51         Opt_legacy, Opt_nodevmap, Opt_unix, Opt_tcp, Opt_fd, Opt_pci,
  52         /* Cache options */
  53         Opt_cache_loose,
  54         /* Error token */
  55         Opt_err
  56 };
  57
  58 static match_table_t tokens = {
  59         {Opt_port, "port=%u"},
  60         {Opt_msize, "msize=%u"},
  61         {Opt_uid, "uid=%u"},
  62         {Opt_gid, "gid=%u"},
  63         {Opt_afid, "afid=%u"},
  64         {Opt_rfdno, "rfdno=%u"},
  65         {Opt_wfdno, "wfdno=%u"},
  66         {Opt_uname, "uname=%s"},
  67         {Opt_remotename, "aname=%s"},
  68         {Opt_unix, "proto=unix"},
  69         {Opt_tcp, "proto=tcp"},
  70         {Opt_fd, "proto=fd"},
  71 #ifdef CONFIG_PCI_9P
  72         {Opt_pci, "proto=pci"},
  73 #endif
  74         {Opt_tcp, "tcp"},
  75         {Opt_unix, "unix"},
  76         {Opt_fd, "fd"},
  77         {Opt_legacy, "noextend"},
  78         {Opt_nodevmap, "nodevmap"},
  79         {Opt_cache_loose, "cache=loose"},
  80         {Opt_cache_loose, "loose"},
  81         {Opt_err, NULL}
  82 };
  83
  84 extern struct p9_transport *p9pci_trans_create(void);
  85
  86 /*
  87  *  Parse option string.
  88  */
  89
  90 /**
  91  * v9fs_parse_options - parse mount options into session structure
  92  * @options: options string passed from mount
  93  * @v9ses: existing v9fs session information
  94  *
  95  */
  96
  97 static void v9fs_parse_options(char *options, struct v9fs_session_info *v9ses)
  98 {
  99         char *p;
 100         substring_t args[MAX_OPT_ARGS];
 101         int option;
 102         int ret;
 103
 104         /* setup defaults */
 105         v9ses->port = V9FS_PORT;
 106         v9ses->maxdata = 9000;
 107         v9ses->proto = PROTO_TCP;
 108         v9ses->extended = 1;
 109         v9ses->afid = ~0;
 110         v9ses->debug = 0;
 111         v9ses->rfdno = ~0;
 112         v9ses->wfdno = ~0;
 113         v9ses->cache = 0;
 114
 115         if (!options)
 116                 return;
 117
 118         while ((p = strsep(&options, ",")) != NULL) {
 119                 int token;
 120                 if (!*p)
 121                         continue;
 122                 token = match_token(p, tokens, args);
 123                 if (token < Opt_uname) {
 124                         if ((ret = match_int(&args[0], &option)) < 0) {
 125                                 P9_DPRINTK(P9_DEBUG_ERROR,
 126                                         "integer field, but no integer?\n");
 127                                 continue;
 128                         }
 129                 }
 130                 switch (token) {
 131                 case Opt_port:
 132                         v9ses->port = option;
 133                         break;
 134                 case Opt_msize:
 135                         v9ses->maxdata = option;
 136                         break;
 137                 case Opt_uid:
 138                         v9ses->uid = option;
 139                         break;
 140                 case Opt_gid:
 141                         v9ses->gid = option;
 142                         break;
 143                 case Opt_afid:
 144                         v9ses->afid = option;
 145                         break;
 146                 case Opt_rfdno:
 147                         v9ses->rfdno = option;
 148                         break;
 149                 case Opt_wfdno:
 150                         v9ses->wfdno = option;
 151                         break;
 152                 case Opt_tcp:
 153                         v9ses->proto = PROTO_TCP;
 154                         break;
 155                 case Opt_unix:
 156                         v9ses->proto = PROTO_UNIX;
 157                         break;
 158                 case Opt_pci:
 159                         v9ses->proto = PROTO_PCI;
 160                         break;
 161                 case Opt_fd:
 162                         v9ses->proto = PROTO_FD;
 163                         break;
 164                 case Opt_uname:
 165                         match_strcpy(v9ses->name, &args[0]);
 166                         break;
 167                 case Opt_remotename:
 168                         match_strcpy(v9ses->remotename, &args[0]);
 169                         break;
 170                 case Opt_legacy:
 171                         v9ses->extended = 0;
 172                         break;
 173                 case Opt_nodevmap:
 174                         v9ses->nodev = 1;
 175                         break;
 176                 case Opt_cache_loose:
 177                         v9ses->cache = CACHE_LOOSE;
 178                         break;
 179                 default:
 180                         continue;
 181                 }
 182         }
 183 }
 184
 185 /**
 186  * v9fs_session_init - initialize session
 187  * @v9ses: session information structure
 188  * @dev_name: device being mounted
 189  * @data: options
 190  *
 191  */
 192
 193 struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
 194                   const char *dev_name, char *data)
 195 {
 196         int retval = -EINVAL;
 197         struct p9_transport *trans;
 198         struct p9_fid *fid;
 199
 200         v9ses->name = __getname();
 201         if (!v9ses->name)
 202                 return ERR_PTR(-ENOMEM);
 203
 204         v9ses->remotename = __getname();
 205         if (!v9ses->remotename) {
 206                 __putname(v9ses->name);
 207                 return ERR_PTR(-ENOMEM);
 208         }
 209
 210         strcpy(v9ses->name, V9FS_DEFUSER);
 211         strcpy(v9ses->remotename, V9FS_DEFANAME);
 212
 213         v9fs_parse_options(data, v9ses);
 214
 215         switch (v9ses->proto) {
 216         case PROTO_TCP:
 217                 trans = p9_trans_create_tcp(dev_name, v9ses->port);
 218                 break;
 219         case PROTO_UNIX:
 220                 trans = p9_trans_create_unix(dev_name);
 221                 *v9ses->remotename = 0;
 222                 break;
 223         case PROTO_FD:
 224                 trans = p9_trans_create_fd(v9ses->rfdno, v9ses->wfdno);
 225                 *v9ses->remotename = 0;
 226                 break;
 227 #ifdef CONFIG_PCI_9P
 228         case PROTO_PCI:
 229                 trans = p9pci_trans_create();
 230                 *v9ses->remotename = 0;
 231                 break;
 232 #endif
 233         default:
 234                 printk(KERN_ERR "v9fs: Bad mount protocol %d\n", v9ses->proto);
 235                 retval = -ENOPROTOOPT;
 236                 goto error;
 237         };
 238
 239         if (IS_ERR(trans)) {
 240                 retval = PTR_ERR(trans);
 241                 trans = NULL;
 242                 goto error;
 243         }
 244
 245         v9ses->clnt = p9_client_create(trans, v9ses->maxdata + P9_IOHDRSZ,
 246                 v9ses->extended);
 247
 248         if (IS_ERR(v9ses->clnt)) {
 249                 retval = PTR_ERR(v9ses->clnt);
 250                 v9ses->clnt = NULL;
 251                 P9_DPRINTK(P9_DEBUG_ERROR, "problem initializing 9p client\n");
 252                 goto error;
 253         }
 254
 255         fid = p9_client_attach(v9ses->clnt, NULL, v9ses->name,
 256                                                         v9ses->remotename);
 257         if (IS_ERR(fid)) {
 258                 retval = PTR_ERR(fid);
 259                 fid = NULL;
 260                 P9_DPRINTK(P9_DEBUG_ERROR, "cannot attach\n");
 261                 goto error;
 262         }
 263
 264         return fid;
 265
 266 error:
 267         v9fs_session_close(v9ses);
 268         return ERR_PTR(retval);
 269 }
 270
 271 /**
 272  * v9fs_session_close - shutdown a session
 273  * @v9ses: session information structure
 274  *
 275  */
 276
 277 void v9fs_session_close(struct v9fs_session_info *v9ses)
 278 {
 279         if (v9ses->clnt) {
 280                 p9_client_destroy(v9ses->clnt);
 281                 v9ses->clnt = NULL;
 282         }
 283
 284         __putname(v9ses->name);
 285         __putname(v9ses->remotename);
 286 }
 287
 288 /**
 289  * v9fs_session_cancel - mark transport as disconnected
 290  *      and cancel all pending requests.
 291  */
 292 void v9fs_session_cancel(struct v9fs_session_info *v9ses) {
 293         P9_DPRINTK(P9_DEBUG_ERROR, "cancel session %p\n", v9ses);
 294         p9_client_disconnect(v9ses->clnt);
 295 }
 296
 297 extern int v9fs_error_init(void);
 298
 299 /**
 300  * v9fs_init - Initialize module
 301  *
 302  */
 303
 304 static int __init init_v9fs(void)
 305 {
 306         printk(KERN_INFO "Installing v9fs 9p2000 file system support\n");
 307
 308         return register_filesystem(&v9fs_fs_type);
 309 }
 310
 311 /**
 312  * v9fs_init - shutdown module
 313  *
 314  */
 315
 316 static void __exit exit_v9fs(void)
 317 {
 318         unregister_filesystem(&v9fs_fs_type);
 319 }
 320
 321 module_init(init_v9fs)
 322 module_exit(exit_v9fs)
 323
 324 MODULE_AUTHOR("Latchesar Ionkov <lucho@ionkov.net>");
 325 MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
 326 MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>");
 327 MODULE_LICENSE("GPL");