fs/9p/9p.c

   1 /*
   2  *  linux/fs/9p/9p.c
   3  *
   4  *  This file contains functions to perform synchronous 9P calls
   5  *
   6  *  Copyright (C) 2004 by Latchesar Ionkov <lucho@ionkov.net>
   7  *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
   8  *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
   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/module.h>
  30 #include <linux/errno.h>
  31 #include <linux/fs.h>
  32 #include <linux/idr.h>
  33
  34 #include "debug.h"
  35 #include "v9fs.h"
  36 #include "9p.h"
  37 #include "conv.h"
  38 #include "mux.h"
  39
  40 /**
  41  * v9fs_t_version - negotiate protocol parameters with sever
  42  * @v9ses: 9P2000 session information
  43  * @msize: requested max size packet
  44  * @version: requested version.extension string
  45  * @fcall: pointer to response fcall pointer
  46  *
  47  */
  48
  49 int
  50 v9fs_t_version(struct v9fs_session_info *v9ses, u32 msize,
  51                char *version, struct v9fs_fcall **rcp)
  52 {
  53         int ret;
  54         struct v9fs_fcall *tc;
  55
  56         dprintk(DEBUG_9P, "msize: %d version: %s\n", msize, version);
  57         tc = v9fs_create_tversion(msize, version);
  58
  59         if (!IS_ERR(tc)) {
  60                 ret = v9fs_mux_rpc(v9ses->mux, tc, rcp);
  61                 kfree(tc);
  62         } else
  63                 ret = PTR_ERR(tc);
  64
  65         return ret;
  66 }
  67
  68 /**
  69  * v9fs_t_attach - mount the server
  70  * @v9ses: 9P2000 session information
  71  * @uname: user name doing the attach
  72  * @aname: remote name being attached to
  73  * @fid: mount fid to attatch to root node
  74  * @afid: authentication fid (in this case result key)
  75  * @fcall: pointer to response fcall pointer
  76  *
  77  */
  78
  79 int
  80 v9fs_t_attach(struct v9fs_session_info *v9ses, char *uname, char *aname,
  81               u32 fid, u32 afid, struct v9fs_fcall **rcp)
  82 {
  83         int ret;
  84         struct v9fs_fcall* tc;
  85
  86         dprintk(DEBUG_9P, "uname '%s' aname '%s' fid %d afid %d\n", uname,
  87                 aname, fid, afid);
  88
  89         tc = v9fs_create_tattach(fid, afid, uname, aname);
  90         if (!IS_ERR(tc)) {
  91                 ret = v9fs_mux_rpc(v9ses->mux, tc, rcp);
  92                 kfree(tc);
  93         } else
  94                 ret = PTR_ERR(tc);
  95
  96         return ret;
  97 }
  98
  99 static void v9fs_t_clunk_cb(void *a, struct v9fs_fcall *tc,
 100         struct v9fs_fcall *rc, int err)
 101 {
 102         int fid;
 103         struct v9fs_session_info *v9ses;
 104
 105         if (err)
 106                 return;
 107
 108         fid = tc->params.tclunk.fid;
 109         kfree(tc);
 110
 111         if (!rc)
 112                 return;
 113
 114         v9ses = a;
 115         if (rc->id == RCLUNK)
 116                 v9fs_put_idpool(fid, &v9ses->fidpool);
 117
 118         kfree(rc);
 119 }
 120
 121 /**
 122  * v9fs_t_clunk - release a fid (finish a transaction)
 123  * @v9ses: 9P2000 session information
 124  * @fid: fid to release
 125  * @fcall: pointer to response fcall pointer
 126  *
 127  */
 128
 129 int
 130 v9fs_t_clunk(struct v9fs_session_info *v9ses, u32 fid)
 131 {
 132         int ret;
 133         struct v9fs_fcall *tc, *rc;
 134
 135         dprintk(DEBUG_9P, "fid %d\n", fid);
 136
 137         rc = NULL;
 138         tc = v9fs_create_tclunk(fid);
 139         if (!IS_ERR(tc))
 140                 ret = v9fs_mux_rpc(v9ses->mux, tc, &rc);
 141         else
 142                 ret = PTR_ERR(tc);
 143
 144         if (ret)
 145                 dprintk(DEBUG_ERROR, "failed fid %d err %d\n", fid, ret);
 146
 147         v9fs_t_clunk_cb(v9ses, tc, rc, ret);
 148         return ret;
 149 }
 150
 151 /**
 152  * v9fs_v9fs_t_flush - flush a pending transaction
 153  * @v9ses: 9P2000 session information
 154  * @tag: tid to release
 155  *
 156  */
 157
 158 int v9fs_t_flush(struct v9fs_session_info *v9ses, u16 oldtag)
 159 {
 160         int ret;
 161         struct v9fs_fcall *tc;
 162
 163         dprintk(DEBUG_9P, "oldtag %d\n", oldtag);
 164
 165         tc = v9fs_create_tflush(oldtag);
 166         if (!IS_ERR(tc)) {
 167                 ret = v9fs_mux_rpc(v9ses->mux, tc, NULL);
 168                 kfree(tc);
 169         } else
 170                 ret = PTR_ERR(tc);
 171
 172         return ret;
 173 }
 174
 175 /**
 176  * v9fs_t_stat - read a file's meta-data
 177  * @v9ses: 9P2000 session information
 178  * @fid: fid pointing to file or directory to get info about
 179  * @fcall: pointer to response fcall
 180  *
 181  */
 182
 183 int
 184 v9fs_t_stat(struct v9fs_session_info *v9ses, u32 fid, struct v9fs_fcall **rcp)
 185 {
 186         int ret;
 187         struct v9fs_fcall *tc;
 188
 189         dprintk(DEBUG_9P, "fid %d\n", fid);
 190
 191         ret = -ENOMEM;
 192         tc = v9fs_create_tstat(fid);
 193         if (!IS_ERR(tc)) {
 194                 ret = v9fs_mux_rpc(v9ses->mux, tc, rcp);
 195                 kfree(tc);
 196         } else
 197                 ret = PTR_ERR(tc);
 198
 199         return ret;
 200 }
 201
 202 /**
 203  * v9fs_t_wstat - write a file's meta-data
 204  * @v9ses: 9P2000 session information
 205  * @fid: fid pointing to file or directory to write info about
 206  * @stat: metadata
 207  * @fcall: pointer to response fcall
 208  *
 209  */
 210
 211 int
 212 v9fs_t_wstat(struct v9fs_session_info *v9ses, u32 fid,
 213              struct v9fs_wstat *wstat, struct v9fs_fcall **rcp)
 214 {
 215         int ret;
 216         struct v9fs_fcall *tc;
 217
 218         dprintk(DEBUG_9P, "fid %d\n", fid);
 219
 220         tc = v9fs_create_twstat(fid, wstat, v9ses->extended);
 221         if (!IS_ERR(tc)) {
 222                 ret = v9fs_mux_rpc(v9ses->mux, tc, rcp);
 223                 kfree(tc);
 224         } else
 225                 ret = PTR_ERR(tc);
 226
 227         return ret;
 228 }
 229
 230 /**
 231  * v9fs_t_walk - walk a fid to a new file or directory
 232  * @v9ses: 9P2000 session information
 233  * @fid: fid to walk
 234  * @newfid: new fid (for clone operations)
 235  * @name: path to walk fid to
 236  * @fcall: pointer to response fcall
 237  *
 238  */
 239
 240 /* TODO: support multiple walk */
 241
 242 int
 243 v9fs_t_walk(struct v9fs_session_info *v9ses, u32 fid, u32 newfid,
 244             char *name, struct v9fs_fcall **rcp)
 245 {
 246         int ret;
 247         struct v9fs_fcall *tc;
 248         int nwname;
 249
 250         dprintk(DEBUG_9P, "fid %d newfid %d wname '%s'\n", fid, newfid, name);
 251
 252         if (name)
 253                 nwname = 1;
 254         else
 255                 nwname = 0;
 256
 257         tc = v9fs_create_twalk(fid, newfid, nwname, &name);
 258         if (!IS_ERR(tc)) {
 259                 ret = v9fs_mux_rpc(v9ses->mux, tc, rcp);
 260                 kfree(tc);
 261         } else
 262                 ret = PTR_ERR(tc);
 263
 264         return ret;
 265 }
 266
 267 /**
 268  * v9fs_t_open - open a file
 269  *
 270  * @v9ses - 9P2000 session information
 271  * @fid - fid to open
 272  * @mode - mode to open file (R, RW, etc)
 273  * @fcall - pointer to response fcall
 274  *
 275  */
 276
 277 int
 278 v9fs_t_open(struct v9fs_session_info *v9ses, u32 fid, u8 mode,
 279             struct v9fs_fcall **rcp)
 280 {
 281         int ret;
 282         struct v9fs_fcall *tc;
 283
 284         dprintk(DEBUG_9P, "fid %d mode %d\n", fid, mode);
 285
 286         tc = v9fs_create_topen(fid, mode);
 287         if (!IS_ERR(tc)) {
 288                 ret = v9fs_mux_rpc(v9ses->mux, tc, rcp);
 289                 kfree(tc);
 290         } else
 291                 ret = PTR_ERR(tc);
 292
 293         return ret;
 294 }
 295
 296 /**
 297  * v9fs_t_remove - remove a file or directory
 298  * @v9ses: 9P2000 session information
 299  * @fid: fid to remove
 300  * @fcall: pointer to response fcall
 301  *
 302  */
 303
 304 int
 305 v9fs_t_remove(struct v9fs_session_info *v9ses, u32 fid,
 306               struct v9fs_fcall **rcp)
 307 {
 308         int ret;
 309         struct v9fs_fcall *tc;
 310
 311         dprintk(DEBUG_9P, "fid %d\n", fid);
 312
 313         tc = v9fs_create_tremove(fid);
 314         if (!IS_ERR(tc)) {
 315                 ret = v9fs_mux_rpc(v9ses->mux, tc, rcp);
 316                 kfree(tc);
 317         } else
 318                 ret = PTR_ERR(tc);
 319
 320         return ret;
 321 }
 322
 323 /**
 324  * v9fs_t_create - create a file or directory
 325  * @v9ses: 9P2000 session information
 326  * @fid: fid to create
 327  * @name: name of the file or directory to create
 328  * @perm: permissions to create with
 329  * @mode: mode to open file (R, RW, etc)
 330  * @fcall: pointer to response fcall
 331  *
 332  */
 333
 334 int
 335 v9fs_t_create(struct v9fs_session_info *v9ses, u32 fid, char *name,
 336               u32 perm, u8 mode, struct v9fs_fcall **rcp)
 337 {
 338         int ret;
 339         struct v9fs_fcall *tc;
 340
 341         dprintk(DEBUG_9P, "fid %d name '%s' perm %x mode %d\n",
 342                 fid, name, perm, mode);
 343
 344         tc = v9fs_create_tcreate(fid, name, perm, mode);
 345         if (!IS_ERR(tc)) {
 346                 ret = v9fs_mux_rpc(v9ses->mux, tc, rcp);
 347                 kfree(tc);
 348         } else
 349                 ret = PTR_ERR(tc);
 350
 351         return ret;
 352 }
 353
 354 /**
 355  * v9fs_t_read - read data
 356  * @v9ses: 9P2000 session information
 357  * @fid: fid to read from
 358  * @offset: offset to start read at
 359  * @count: how many bytes to read
 360  * @fcall: pointer to response fcall (with data)
 361  *
 362  */
 363
 364 int
 365 v9fs_t_read(struct v9fs_session_info *v9ses, u32 fid, u64 offset,
 366             u32 count, struct v9fs_fcall **rcp)
 367 {
 368         int ret;
 369         struct v9fs_fcall *tc, *rc;
 370
 371         dprintk(DEBUG_9P, "fid %d offset 0x%llux count 0x%x\n", fid,
 372                 (long long unsigned) offset, count);
 373
 374         tc = v9fs_create_tread(fid, offset, count);
 375         if (!IS_ERR(tc)) {
 376                 ret = v9fs_mux_rpc(v9ses->mux, tc, &rc);
 377                 if (!ret)
 378                         ret = rc->params.rread.count;
 379                 if (rcp)
 380                         *rcp = rc;
 381                 else
 382                         kfree(rc);
 383
 384                 kfree(tc);
 385         } else
 386                 ret = PTR_ERR(tc);
 387
 388         return ret;
 389 }
 390
 391 /**
 392  * v9fs_t_write - write data
 393  * @v9ses: 9P2000 session information
 394  * @fid: fid to write to
 395  * @offset: offset to start write at
 396  * @count: how many bytes to write
 397  * @fcall: pointer to response fcall
 398  *
 399  */
 400
 401 int
 402 v9fs_t_write(struct v9fs_session_info *v9ses, u32 fid, u64 offset, u32 count,
 403         const char __user *data, struct v9fs_fcall **rcp)
 404 {
 405         int ret;
 406         struct v9fs_fcall *tc, *rc;
 407
 408         dprintk(DEBUG_9P, "fid %d offset 0x%llux count 0x%x\n", fid,
 409                 (long long unsigned) offset, count);
 410
 411         tc = v9fs_create_twrite(fid, offset, count, data);
 412         if (!IS_ERR(tc)) {
 413                 ret = v9fs_mux_rpc(v9ses->mux, tc, &rc);
 414
 415                 if (!ret)
 416                         ret = rc->params.rwrite.count;
 417                 if (rcp)
 418                         *rcp = rc;
 419                 else
 420                         kfree(rc);
 421
 422                 kfree(tc);
 423         } else
 424                 ret = PTR_ERR(tc);
 425
 426         return ret;
 427 }
 428