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_debug, 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_debug, "debug=%x"},
  60         {Opt_port, "port=%u"},
  61         {Opt_msize, "msize=%u"},
  62         {Opt_uid, "uid=%u"},
  63         {Opt_gid, "gid=%u"},
  64         {Opt_afid, "afid=%u"},
  65         {Opt_rfdno, "rfdno=%u"},
  66         {Opt_wfdno, "wfdno=%u"},
  67         {Opt_uname, "uname=%s"},
  68         {Opt_remotename, "aname=%s"},
  69         {Opt_unix, "proto=unix"},
  70         {Opt_tcp, "proto=tcp"},
  71         {Opt_fd, "proto=fd"},
  72 #ifdef CONFIG_PCI_9P
  73         {Opt_pci, "proto=pci"},
  74 #endif
  75         {Opt_tcp, "tcp"},
  76         {Opt_unix, "unix"},
  77         {Opt_fd, "fd"},
  78         {Opt_legacy, "noextend"},
  79         {Opt_nodevmap, "nodevmap"},
  80         {Opt_cache_loose, "cache=loose"},
  81         {Opt_cache_loose, "loose"},
  82         {Opt_err, NULL}
  83 };
  84
  85 extern struct p9_transport *p9pci_trans_create(void);
  86
  87 /*
  88  *  Parse option string.
  89  */
  90
  91 /**
  92  * v9fs_parse_options - parse mount options into session structure
  93  * @options: options string passed from mount
  94  * @v9ses: existing v9fs session information
  95  *
  96  */
  97
  98 static void v9fs_parse_options(char *options, struct v9fs_session_info *v9ses)
  99 {
 100         char *p;
 101         substring_t args[MAX_OPT_ARGS];
 102         int option;
 103         int ret;
 104
 105         /* setup defaults */
 106         v9ses->port = V9FS_PORT;
 107         v9ses->maxdata = 9000;
 108         v9ses->proto = PROTO_TCP;
 109         v9ses->extended = 1;
 110         v9ses->afid = ~0;
 111         v9ses->debug = 0;
 112         v9ses->rfdno = ~0;
 113         v9ses->wfdno = ~0;
 114         v9ses->cache = 0;
 115
 116         if (!options)
 117                 return;
 118
 119         while ((p = strsep(&options, ",")) != NULL) {
 120                 int token;
 121                 if (!*p)
 122                         continue;
 123                 token = match_token(p, tokens, args);
 124                 if (token < Opt_uname) {
 125                         if ((ret = match_int(&args[0], &option)) < 0) {
 126                                 P9_DPRINTK(P9_DEBUG_ERROR,
 127                                         "integer field, but no integer?\n");
 128                                 continue;
 129                         }
 130                 }
 131                 switch (token) {
 132                 case Opt_debug:
 133                         v9ses->debug = option;
 134                         p9_debug_level = option;
 135                         break;
 136                 case Opt_port:
 137                         v9ses->port = option;
 138                         break;
 139                 case Opt_msize:
 140                         v9ses->maxdata = option;
 141                         break;
 142                 case Opt_uid:
 143                         v9ses->uid = option;
 144                         break;
 145                 case Opt_gid:
 146                         v9ses->gid = option;
 147                         break;
 148                 case Opt_afid:
 149                         v9ses->afid = option;
 150                         break;
 151                 case Opt_rfdno:
 152                         v9ses->rfdno = option;
 153                         break;
 154                 case Opt_wfdno:
 155                         v9ses->wfdno = option;
 156                         break;
 157                 case Opt_tcp:
 158                         v9ses->proto = PROTO_TCP;
 159                         break;
 160                 case Opt_unix:
 161                         v9ses->proto = PROTO_UNIX;
 162                         break;
 163                 case Opt_pci:
 164                         v9ses->proto = PROTO_PCI;
 165                         break;
 166                 case Opt_fd:
 167                         v9ses->proto = PROTO_FD;
 168                         break;
 169                 case Opt_uname:
 170                         match_strcpy(v9ses->name, &args[0]);
 171                         break;
 172                 case Opt_remotename:
 173                         match_strcpy(v9ses->remotename, &args[0]);
 174                         break;
 175                 case Opt_legacy:
 176                         v9ses->extended = 0;
 177                         break;
 178                 case Opt_nodevmap:
 179                         v9ses->nodev = 1;
 180                         break;
 181                 case Opt_cache_loose:
 182                         v9ses->cache = CACHE_LOOSE;
 183                         break;
 184                 default:
 185                         continue;
 186                 }
 187         }
 188 }
 189
 190 /**
 191  * v9fs_session_init - initialize session
 192  * @v9ses: session information structure
 193  * @dev_name: device being mounted
 194  * @data: options
 195  *
 196  */
 197
 198 struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
 199                   const char *dev_name, char *data)
 200 {
 201         int retval = -EINVAL;
 202         struct p9_transport *trans;
 203         struct p9_fid *fid;
 204
 205         v9ses->name = __getname();
 206         if (!v9ses->name)
 207                 return ERR_PTR(-ENOMEM);
 208
 209         v9ses->remotename = __getname();
 210         if (!v9ses->remotename) {
 211                 __putname(v9ses->name);
 212                 return ERR_PTR(-ENOMEM);
 213         }
 214
 215         strcpy(v9ses->name, V9FS_DEFUSER);
 216         strcpy(v9ses->remotename, V9FS_DEFANAME);
 217
 218         v9fs_parse_options(data, v9ses);
 219
 220         switch (v9ses->proto) {
 221         case PROTO_TCP:
 222                 trans = p9_trans_create_tcp(dev_name, v9ses->port);
 223                 break;
 224         case PROTO_UNIX:
 225                 trans = p9_trans_create_unix(dev_name);
 226                 *v9ses->remotename = 0;
 227                 break;
 228         case PROTO_FD:
 229                 trans = p9_trans_create_fd(v9ses->rfdno, v9ses->wfdno);
 230                 *v9ses->remotename = 0;
 231                 break;
 232 #ifdef CONFIG_PCI_9P
 233         case PROTO_PCI:
 234                 trans = p9pci_trans_create();
 235                 *v9ses->remotename = 0;
 236                 break;
 237 #endif
 238         default:
 239                 printk(KERN_ERR "v9fs: Bad mount protocol %d\n", v9ses->proto);
 240                 retval = -ENOPROTOOPT;
 241                 goto error;
 242         };
 243
 244         if (IS_ERR(trans)) {
 245                 retval = PTR_ERR(trans);
 246                 trans = NULL;
 247                 goto error;
 248         }
 249
 250         v9ses->clnt = p9_client_create(trans, v9ses->maxdata + P9_IOHDRSZ,
 251                 v9ses->extended);
 252
 253         if (IS_ERR(v9ses->clnt)) {
 254                 retval = PTR_ERR(v9ses->clnt);
 255                 v9ses->clnt = NULL;
 256                 P9_DPRINTK(P9_DEBUG_ERROR, "problem initializing 9p client\n");
 257                 goto error;
 258         }
 259
 260         fid = p9_client_attach(v9ses->clnt, NULL, v9ses->name,
 261                                                         v9ses->remotename);
 262         if (IS_ERR(fid)) {
 263                 retval = PTR_ERR(fid);
 264                 fid = NULL;
 265                 P9_DPRINTK(P9_DEBUG_ERROR, "cannot attach\n");
 266                 goto error;
 267         }
 268
 269         return fid;
 270
 271 error:
 272         v9fs_session_close(v9ses);
 273         return ERR_PTR(retval);
 274 }
 275
 276 /**
 277  * v9fs_session_close - shutdown a session
 278  * @v9ses: session information structure
 279  *
 280  */
 281
 282 void v9fs_session_close(struct v9fs_session_info *v9ses)
 283 {
 284         if (v9ses->clnt) {
 285                 p9_client_destroy(v9ses->clnt);
 286                 v9ses->clnt = NULL;
 287         }
 288
 289         __putname(v9ses->name);
 290         __putname(v9ses->remotename);
 291 }
 292
 293 /**
 294  * v9fs_session_cancel - mark transport as disconnected
 295  *      and cancel all pending requests.
 296  */
 297 void v9fs_session_cancel(struct v9fs_session_info *v9ses) {
 298         P9_DPRINTK(P9_DEBUG_ERROR, "cancel session %p\n", v9ses);
 299         p9_client_disconnect(v9ses->clnt);
 300 }
 301
 302 extern int v9fs_error_init(void);
 303
 304 /**
 305  * v9fs_init - Initialize module
 306  *
 307  */
 308
 309 static int __init init_v9fs(void)
 310 {
 311         printk(KERN_INFO "Installing v9fs 9p2000 file system support\n");
 312
 313         return register_filesystem(&v9fs_fs_type);
 314 }
 315
 316 /**
 317  * v9fs_init - shutdown module
 318  *
 319  */
 320
 321 static void __exit exit_v9fs(void)
 322 {
 323         unregister_filesystem(&v9fs_fs_type);
 324 }
 325
 326 module_init(init_v9fs)
 327 module_exit(exit_v9fs)
 328
 329 MODULE_AUTHOR("Latchesar Ionkov <lucho@ionkov.net>");
 330 MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
 331 MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>");
 332 MODULE_LICENSE("GPL");