fs/9p/vfs_inode.c

   1 /*
   2  *  linux/fs/9p/vfs_inode.c
   3  *
   4  * This file contains vfs inode ops for the 9P2000 protocol.
   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/file.h>
  30 #include <linux/pagemap.h>
  31 #include <linux/stat.h>
  32 #include <linux/string.h>
  33 #include <linux/inet.h>
  34 #include <linux/namei.h>
  35 #include <linux/idr.h>
  36 #include <linux/sched.h>
  37 #include <net/9p/9p.h>
  38 #include <net/9p/client.h>
  39
  40 #include "v9fs.h"
  41 #include "v9fs_vfs.h"
  42 #include "fid.h"
  43
  44 static const struct inode_operations v9fs_dir_inode_operations;
  45 static const struct inode_operations v9fs_dir_inode_operations_ext;
  46 static const struct inode_operations v9fs_file_inode_operations;
  47 static const struct inode_operations v9fs_symlink_inode_operations;
  48
  49 /**
  50  * unixmode2p9mode - convert unix mode bits to plan 9
  51  * @v9ses: v9fs session information
  52  * @mode: mode to convert
  53  *
  54  */
  55
  56 static int unixmode2p9mode(struct v9fs_session_info *v9ses, int mode)
  57 {
  58         int res;
  59         res = mode & 0777;
  60         if (S_ISDIR(mode))
  61                 res |= P9_DMDIR;
  62         if (v9fs_extended(v9ses)) {
  63                 if (S_ISLNK(mode))
  64                         res |= P9_DMSYMLINK;
  65                 if (v9ses->nodev == 0) {
  66                         if (S_ISSOCK(mode))
  67                                 res |= P9_DMSOCKET;
  68                         if (S_ISFIFO(mode))
  69                                 res |= P9_DMNAMEDPIPE;
  70                         if (S_ISBLK(mode))
  71                                 res |= P9_DMDEVICE;
  72                         if (S_ISCHR(mode))
  73                                 res |= P9_DMDEVICE;
  74                 }
  75
  76                 if ((mode & S_ISUID) == S_ISUID)
  77                         res |= P9_DMSETUID;
  78                 if ((mode & S_ISGID) == S_ISGID)
  79                         res |= P9_DMSETGID;
  80                 if ((mode & S_ISVTX) == S_ISVTX)
  81                         res |= P9_DMSETVTX;
  82                 if ((mode & P9_DMLINK))
  83                         res |= P9_DMLINK;
  84         }
  85
  86         return res;
  87 }
  88
  89 /**
  90  * p9mode2unixmode- convert plan9 mode bits to unix mode bits
  91  * @v9ses: v9fs session information
  92  * @mode: mode to convert
  93  *
  94  */
  95
  96 static int p9mode2unixmode(struct v9fs_session_info *v9ses, int mode)
  97 {
  98         int res;
  99
 100         res = mode & 0777;
 101
 102         if ((mode & P9_DMDIR) == P9_DMDIR)
 103                 res |= S_IFDIR;
 104         else if ((mode & P9_DMSYMLINK) && (v9fs_extended(v9ses)))
 105                 res |= S_IFLNK;
 106         else if ((mode & P9_DMSOCKET) && (v9fs_extended(v9ses))
 107                  && (v9ses->nodev == 0))
 108                 res |= S_IFSOCK;
 109         else if ((mode & P9_DMNAMEDPIPE) && (v9fs_extended(v9ses))
 110                  && (v9ses->nodev == 0))
 111                 res |= S_IFIFO;
 112         else if ((mode & P9_DMDEVICE) && (v9fs_extended(v9ses))
 113                  && (v9ses->nodev == 0))
 114                 res |= S_IFBLK;
 115         else
 116                 res |= S_IFREG;
 117
 118         if (v9fs_extended(v9ses)) {
 119                 if ((mode & P9_DMSETUID) == P9_DMSETUID)
 120                         res |= S_ISUID;
 121
 122                 if ((mode & P9_DMSETGID) == P9_DMSETGID)
 123                         res |= S_ISGID;
 124
 125                 if ((mode & P9_DMSETVTX) == P9_DMSETVTX)
 126                         res |= S_ISVTX;
 127         }
 128
 129         return res;
 130 }
 131
 132 /**
 133  * v9fs_uflags2omode- convert posix open flags to plan 9 mode bits
 134  * @uflags: flags to convert
 135  * @extended: if .u extensions are active
 136  */
 137
 138 int v9fs_uflags2omode(int uflags, int extended)
 139 {
 140         int ret;
 141
 142         ret = 0;
 143         switch (uflags&3) {
 144         default:
 145         case O_RDONLY:
 146                 ret = P9_OREAD;
 147                 break;
 148
 149         case O_WRONLY:
 150                 ret = P9_OWRITE;
 151                 break;
 152
 153         case O_RDWR:
 154                 ret = P9_ORDWR;
 155                 break;
 156         }
 157
 158         if (uflags & O_TRUNC)
 159                 ret |= P9_OTRUNC;
 160
 161         if (extended) {
 162                 if (uflags & O_EXCL)
 163                         ret |= P9_OEXCL;
 164
 165                 if (uflags & O_APPEND)
 166                         ret |= P9_OAPPEND;
 167         }
 168
 169         return ret;
 170 }
 171
 172 /**
 173  * v9fs_blank_wstat - helper function to setup a 9P stat structure
 174  * @v9ses: 9P session info (for determining extended mode)
 175  * @wstat: structure to initialize
 176  *
 177  */
 178
 179 static void
 180 v9fs_blank_wstat(struct p9_wstat *wstat)
 181 {
 182         wstat->type = ~0;
 183         wstat->dev = ~0;
 184         wstat->qid.type = ~0;
 185         wstat->qid.version = ~0;
 186         *((long long *)&wstat->qid.path) = ~0;
 187         wstat->mode = ~0;
 188         wstat->atime = ~0;
 189         wstat->mtime = ~0;
 190         wstat->length = ~0;
 191         wstat->name = NULL;
 192         wstat->uid = NULL;
 193         wstat->gid = NULL;
 194         wstat->muid = NULL;
 195         wstat->n_uid = ~0;
 196         wstat->n_gid = ~0;
 197         wstat->n_muid = ~0;
 198         wstat->extension = NULL;
 199 }
 200
 201 /**
 202  * v9fs_get_inode - helper function to setup an inode
 203  * @sb: superblock
 204  * @mode: mode to setup inode with
 205  *
 206  */
 207
 208 struct inode *v9fs_get_inode(struct super_block *sb, int mode)
 209 {
 210         struct inode *inode;
 211         struct v9fs_session_info *v9ses = sb->s_fs_info;
 212
 213         P9_DPRINTK(P9_DEBUG_VFS, "super block: %p mode: %o\n", sb, mode);
 214
 215         inode = new_inode(sb);
 216         if (inode) {
 217                 inode->i_mode = mode;
 218                 inode->i_uid = current_fsuid();
 219                 inode->i_gid = current_fsgid();
 220                 inode->i_blocks = 0;
 221                 inode->i_rdev = 0;
 222                 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
 223                 inode->i_mapping->a_ops = &v9fs_addr_operations;
 224
 225                 switch (mode & S_IFMT) {
 226                 case S_IFIFO:
 227                 case S_IFBLK:
 228                 case S_IFCHR:
 229                 case S_IFSOCK:
 230                         if (!v9fs_extended(v9ses)) {
 231                                 P9_DPRINTK(P9_DEBUG_ERROR,
 232                                       "special files without extended mode\n");
 233                                 return ERR_PTR(-EINVAL);
 234                         }
 235                         init_special_inode(inode, inode->i_mode,
 236                                            inode->i_rdev);
 237                         break;
 238                 case S_IFREG:
 239                         inode->i_op = &v9fs_file_inode_operations;
 240                         inode->i_fop = &v9fs_file_operations;
 241                         break;
 242                 case S_IFLNK:
 243                         if (!v9fs_extended(v9ses)) {
 244                                 P9_DPRINTK(P9_DEBUG_ERROR,
 245                                         "extended modes used w/o 9P2000.u\n");
 246                                 return ERR_PTR(-EINVAL);
 247                         }
 248                         inode->i_op = &v9fs_symlink_inode_operations;
 249                         break;
 250                 case S_IFDIR:
 251                         inc_nlink(inode);
 252                         if (v9fs_extended(v9ses))
 253                                 inode->i_op = &v9fs_dir_inode_operations_ext;
 254                         else
 255                                 inode->i_op = &v9fs_dir_inode_operations;
 256                         inode->i_fop = &v9fs_dir_operations;
 257                         break;
 258                 default:
 259                         P9_DPRINTK(P9_DEBUG_ERROR,
 260                                 "BAD mode 0x%x S_IFMT 0x%x\n",
 261                                 mode, mode & S_IFMT);
 262                         return ERR_PTR(-EINVAL);
 263                 }
 264         } else {
 265                 P9_EPRINTK(KERN_WARNING, "Problem allocating inode\n");
 266                 return ERR_PTR(-ENOMEM);
 267         }
 268         return inode;
 269 }
 270
 271 /*
 272 static struct v9fs_fid*
 273 v9fs_clone_walk(struct v9fs_session_info *v9ses, u32 fid, struct dentry *dentry)
 274 {
 275         int err;
 276         int nfid;
 277         struct v9fs_fid *ret;
 278         struct v9fs_fcall *fcall;
 279
 280         nfid = v9fs_get_idpool(&v9ses->fidpool);
 281         if (nfid < 0) {
 282                 eprintk(KERN_WARNING, "no free fids available\n");
 283                 return ERR_PTR(-ENOSPC);
 284         }
 285
 286         err = v9fs_t_walk(v9ses, fid, nfid, (char *) dentry->d_name.name,
 287                 &fcall);
 288
 289         if (err < 0) {
 290                 if (fcall && fcall->id == RWALK)
 291                         goto clunk_fid;
 292
 293                 PRINT_FCALL_ERROR("walk error", fcall);
 294                 v9fs_put_idpool(nfid, &v9ses->fidpool);
 295                 goto error;
 296         }
 297
 298         kfree(fcall);
 299         fcall = NULL;
 300         ret = v9fs_fid_create(v9ses, nfid);
 301         if (!ret) {
 302                 err = -ENOMEM;
 303                 goto clunk_fid;
 304         }
 305
 306         err = v9fs_fid_insert(ret, dentry);
 307         if (err < 0) {
 308                 v9fs_fid_destroy(ret);
 309                 goto clunk_fid;
 310         }
 311
 312         return ret;
 313
 314 clunk_fid:
 315         v9fs_t_clunk(v9ses, nfid);
 316
 317 error:
 318         kfree(fcall);
 319         return ERR_PTR(err);
 320 }
 321 */
 322
 323 /**
 324  * v9fs_inode_from_fid - populate an inode by issuing a attribute request
 325  * @v9ses: session information
 326  * @fid: fid to issue attribute request for
 327  * @sb: superblock on which to create inode
 328  *
 329  */
 330
 331 static struct inode *
 332 v9fs_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
 333         struct super_block *sb)
 334 {
 335         int err, umode;
 336         struct inode *ret;
 337         struct p9_wstat *st;
 338
 339         ret = NULL;
 340         st = p9_client_stat(fid);
 341         if (IS_ERR(st)) {
 342                 err = PTR_ERR(st);
 343                 st = NULL;
 344                 goto error;
 345         }
 346
 347         umode = p9mode2unixmode(v9ses, st->mode);
 348         ret = v9fs_get_inode(sb, umode);
 349         if (IS_ERR(ret)) {
 350                 err = PTR_ERR(ret);
 351                 ret = NULL;
 352                 goto error;
 353         }
 354
 355         v9fs_stat2inode(st, ret, sb);
 356         ret->i_ino = v9fs_qid2ino(&st->qid);
 357         kfree(st);
 358         return ret;
 359
 360 error:
 361         kfree(st);
 362         if (ret)
 363                 iput(ret);
 364
 365         return ERR_PTR(err);
 366 }
 367
 368 /**
 369  * v9fs_remove - helper function to remove files and directories
 370  * @dir: directory inode that is being deleted
 371  * @file:  dentry that is being deleted
 372  * @rmdir: removing a directory
 373  *
 374  */
 375
 376 static int v9fs_remove(struct inode *dir, struct dentry *file, int rmdir)
 377 {
 378         struct inode *file_inode;
 379         struct v9fs_session_info *v9ses;
 380         struct p9_fid *v9fid;
 381
 382         P9_DPRINTK(P9_DEBUG_VFS, "inode: %p dentry: %p rmdir: %d\n", dir, file,
 383                 rmdir);
 384
 385         file_inode = file->d_inode;
 386         v9ses = v9fs_inode2v9ses(file_inode);
 387         v9fid = v9fs_fid_clone(file);
 388         if (IS_ERR(v9fid))
 389                 return PTR_ERR(v9fid);
 390
 391         return p9_client_remove(v9fid);
 392 }
 393
 394 static int
 395 v9fs_open_created(struct inode *inode, struct file *file)
 396 {
 397         return 0;
 398 }
 399
 400
 401 /**
 402  * v9fs_create - Create a file
 403  * @v9ses: session information
 404  * @dir: directory that dentry is being created in
 405  * @dentry:  dentry that is being created
 406  * @perm: create permissions
 407  * @mode: open mode
 408  * @extension: 9p2000.u extension string to support devices, etc.
 409  *
 410  */
 411 static struct p9_fid *
 412 v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
 413                 struct dentry *dentry, char *extension, u32 perm, u8 mode)
 414 {
 415         int err;
 416         char *name;
 417         struct p9_fid *dfid, *ofid, *fid;
 418         struct inode *inode;
 419
 420         P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name);
 421
 422         err = 0;
 423         ofid = NULL;
 424         fid = NULL;
 425         name = (char *) dentry->d_name.name;
 426         dfid = v9fs_fid_clone(dentry->d_parent);
 427         if (IS_ERR(dfid)) {
 428                 err = PTR_ERR(dfid);
 429                 P9_DPRINTK(P9_DEBUG_VFS, "fid clone failed %d\n", err);
 430                 dfid = NULL;
 431                 goto error;
 432         }
 433
 434         /* clone a fid to use for creation */
 435         ofid = p9_client_walk(dfid, 0, NULL, 1);
 436         if (IS_ERR(ofid)) {
 437                 err = PTR_ERR(ofid);
 438                 P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
 439                 ofid = NULL;
 440                 goto error;
 441         }
 442
 443         err = p9_client_fcreate(ofid, name, perm, mode, extension);
 444         if (err < 0) {
 445                 P9_DPRINTK(P9_DEBUG_VFS, "p9_client_fcreate failed %d\n", err);
 446                 goto error;
 447         }
 448
 449         /* now walk from the parent so we can get unopened fid */
 450         fid = p9_client_walk(dfid, 1, &name, 0);
 451         if (IS_ERR(fid)) {
 452                 err = PTR_ERR(fid);
 453                 P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
 454                 fid = NULL;
 455                 goto error;
 456         } else
 457                 dfid = NULL;
 458
 459         /* instantiate inode and assign the unopened fid to the dentry */
 460         inode = v9fs_inode_from_fid(v9ses, fid, dir->i_sb);
 461         if (IS_ERR(inode)) {
 462                 err = PTR_ERR(inode);
 463                 P9_DPRINTK(P9_DEBUG_VFS, "inode creation failed %d\n", err);
 464                 goto error;
 465         }
 466
 467         if (v9ses->cache)
 468                 dentry->d_op = &v9fs_cached_dentry_operations;
 469         else
 470                 dentry->d_op = &v9fs_dentry_operations;
 471
 472         d_instantiate(dentry, inode);
 473         v9fs_fid_add(dentry, fid);
 474         return ofid;
 475
 476 error:
 477         if (dfid)
 478                 p9_client_clunk(dfid);
 479
 480         if (ofid)
 481                 p9_client_clunk(ofid);
 482
 483         if (fid)
 484                 p9_client_clunk(fid);
 485
 486         return ERR_PTR(err);
 487 }
 488
 489 /**
 490  * v9fs_vfs_create - VFS hook to create files
 491  * @dir: directory inode that is being created
 492  * @dentry:  dentry that is being deleted
 493  * @mode: create permissions
 494  * @nd: path information
 495  *
 496  */
 497
 498 static int
 499 v9fs_vfs_create(struct inode *dir, struct dentry *dentry, int mode,
 500                 struct nameidata *nd)
 501 {
 502         int err;
 503         u32 perm;
 504         int flags;
 505         struct v9fs_session_info *v9ses;
 506         struct p9_fid *fid;
 507         struct file *filp;
 508
 509         err = 0;
 510         fid = NULL;
 511         v9ses = v9fs_inode2v9ses(dir);
 512         perm = unixmode2p9mode(v9ses, mode);
 513         if (nd && nd->flags & LOOKUP_OPEN)
 514                 flags = nd->intent.open.flags - 1;
 515         else
 516                 flags = O_RDWR;
 517
 518         fid = v9fs_create(v9ses, dir, dentry, NULL, perm,
 519                                 v9fs_uflags2omode(flags, v9fs_extended(v9ses)));
 520         if (IS_ERR(fid)) {
 521                 err = PTR_ERR(fid);
 522                 fid = NULL;
 523                 goto error;
 524         }
 525
 526         /* if we are opening a file, assign the open fid to the file */
 527         if (nd && nd->flags & LOOKUP_OPEN) {
 528                 filp = lookup_instantiate_filp(nd, dentry, v9fs_open_created);
 529                 if (IS_ERR(filp)) {
 530                         err = PTR_ERR(filp);
 531                         goto error;
 532                 }
 533
 534                 filp->private_data = fid;
 535         } else
 536                 p9_client_clunk(fid);
 537
 538         return 0;
 539
 540 error:
 541         if (fid)
 542                 p9_client_clunk(fid);
 543
 544         return err;
 545 }
 546
 547 /**
 548  * v9fs_vfs_mkdir - VFS mkdir hook to create a directory
 549  * @dir:  inode that is being unlinked
 550  * @dentry: dentry that is being unlinked
 551  * @mode: mode for new directory
 552  *
 553  */
 554
 555 static int v9fs_vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 556 {
 557         int err;
 558         u32 perm;
 559         struct v9fs_session_info *v9ses;
 560         struct p9_fid *fid;
 561
 562         P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name);
 563         err = 0;
 564         v9ses = v9fs_inode2v9ses(dir);
 565         perm = unixmode2p9mode(v9ses, mode | S_IFDIR);
 566         fid = v9fs_create(v9ses, dir, dentry, NULL, perm, P9_OREAD);
 567         if (IS_ERR(fid)) {
 568                 err = PTR_ERR(fid);
 569                 fid = NULL;
 570         }
 571
 572         if (fid)
 573                 p9_client_clunk(fid);
 574
 575         return err;
 576 }
 577
 578 /**
 579  * v9fs_vfs_lookup - VFS lookup hook to "walk" to a new inode
 580  * @dir:  inode that is being walked from
 581  * @dentry: dentry that is being walked to?
 582  * @nameidata: path data
 583  *
 584  */
 585
 586 static struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
 587                                       struct nameidata *nameidata)
 588 {
 589         struct super_block *sb;
 590         struct v9fs_session_info *v9ses;
 591         struct p9_fid *dfid, *fid;
 592         struct inode *inode;
 593         char *name;
 594         int result = 0;
 595
 596         P9_DPRINTK(P9_DEBUG_VFS, "dir: %p dentry: (%s) %p nameidata: %p\n",
 597                 dir, dentry->d_name.name, dentry, nameidata);
 598
 599         sb = dir->i_sb;
 600         v9ses = v9fs_inode2v9ses(dir);
 601         dfid = v9fs_fid_lookup(dentry->d_parent);
 602         if (IS_ERR(dfid))
 603                 return ERR_CAST(dfid);
 604
 605         name = (char *) dentry->d_name.name;
 606         fid = p9_client_walk(dfid, 1, &name, 1);
 607         if (IS_ERR(fid)) {
 608                 result = PTR_ERR(fid);
 609                 if (result == -ENOENT) {
 610                         d_add(dentry, NULL);
 611                         return NULL;
 612                 }
 613
 614                 return ERR_PTR(result);
 615         }
 616
 617         inode = v9fs_inode_from_fid(v9ses, fid, dir->i_sb);
 618         if (IS_ERR(inode)) {
 619                 result = PTR_ERR(inode);
 620                 inode = NULL;
 621                 goto error;
 622         }
 623
 624         result = v9fs_fid_add(dentry, fid);
 625         if (result < 0)
 626                 goto error;
 627
 628         if ((fid->qid.version) && (v9ses->cache))
 629                 dentry->d_op = &v9fs_cached_dentry_operations;
 630         else
 631                 dentry->d_op = &v9fs_dentry_operations;
 632
 633         d_add(dentry, inode);
 634         return NULL;
 635
 636 error:
 637         p9_client_clunk(fid);
 638
 639         return ERR_PTR(result);
 640 }
 641
 642 /**
 643  * v9fs_vfs_unlink - VFS unlink hook to delete an inode
 644  * @i:  inode that is being unlinked
 645  * @d: dentry that is being unlinked
 646  *
 647  */
 648
 649 static int v9fs_vfs_unlink(struct inode *i, struct dentry *d)
 650 {
 651         return v9fs_remove(i, d, 0);
 652 }
 653
 654 /**
 655  * v9fs_vfs_rmdir - VFS unlink hook to delete a directory
 656  * @i:  inode that is being unlinked
 657  * @d: dentry that is being unlinked
 658  *
 659  */
 660
 661 static int v9fs_vfs_rmdir(struct inode *i, struct dentry *d)
 662 {
 663         return v9fs_remove(i, d, 1);
 664 }
 665
 666 /**
 667  * v9fs_vfs_rename - VFS hook to rename an inode
 668  * @old_dir:  old dir inode
 669  * @old_dentry: old dentry
 670  * @new_dir: new dir inode
 671  * @new_dentry: new dentry
 672  *
 673  */
 674
 675 static int
 676 v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 677                 struct inode *new_dir, struct dentry *new_dentry)
 678 {
 679         struct inode *old_inode;
 680         struct v9fs_session_info *v9ses;
 681         struct p9_fid *oldfid;
 682         struct p9_fid *olddirfid;
 683         struct p9_fid *newdirfid;
 684         struct p9_wstat wstat;
 685         int retval;
 686
 687         P9_DPRINTK(P9_DEBUG_VFS, "\n");
 688         retval = 0;
 689         old_inode = old_dentry->d_inode;
 690         v9ses = v9fs_inode2v9ses(old_inode);
 691         oldfid = v9fs_fid_lookup(old_dentry);
 692         if (IS_ERR(oldfid))
 693                 return PTR_ERR(oldfid);
 694
 695         olddirfid = v9fs_fid_clone(old_dentry->d_parent);
 696         if (IS_ERR(olddirfid)) {
 697                 retval = PTR_ERR(olddirfid);
 698                 goto done;
 699         }
 700
 701         newdirfid = v9fs_fid_clone(new_dentry->d_parent);
 702         if (IS_ERR(newdirfid)) {
 703                 retval = PTR_ERR(newdirfid);
 704                 goto clunk_olddir;
 705         }
 706
 707         /* 9P can only handle file rename in the same directory */
 708         if (memcmp(&olddirfid->qid, &newdirfid->qid, sizeof(newdirfid->qid))) {
 709                 P9_DPRINTK(P9_DEBUG_ERROR,
 710                                 "old dir and new dir are different\n");
 711                 retval = -EXDEV;
 712                 goto clunk_newdir;
 713         }
 714
 715         v9fs_blank_wstat(&wstat);
 716         wstat.muid = v9ses->uname;
 717         wstat.name = (char *) new_dentry->d_name.name;
 718         retval = p9_client_wstat(oldfid, &wstat);
 719
 720 clunk_newdir:
 721         p9_client_clunk(newdirfid);
 722
 723 clunk_olddir:
 724         p9_client_clunk(olddirfid);
 725
 726 done:
 727         return retval;
 728 }
 729
 730 /**
 731  * v9fs_vfs_getattr - retrieve file metadata
 732  * @mnt: mount information
 733  * @dentry: file to get attributes on
 734  * @stat: metadata structure to populate
 735  *
 736  */
 737
 738 static int
 739 v9fs_vfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
 740                  struct kstat *stat)
 741 {
 742         int err;
 743         struct v9fs_session_info *v9ses;
 744         struct p9_fid *fid;
 745         struct p9_wstat *st;
 746
 747         P9_DPRINTK(P9_DEBUG_VFS, "dentry: %p\n", dentry);
 748         err = -EPERM;
 749         v9ses = v9fs_inode2v9ses(dentry->d_inode);
 750         if (v9ses->cache == CACHE_LOOSE)
 751                 return simple_getattr(mnt, dentry, stat);
 752
 753         fid = v9fs_fid_lookup(dentry);
 754         if (IS_ERR(fid))
 755                 return PTR_ERR(fid);
 756
 757         st = p9_client_stat(fid);
 758         if (IS_ERR(st))
 759                 return PTR_ERR(st);
 760
 761         v9fs_stat2inode(st, dentry->d_inode, dentry->d_inode->i_sb);
 762                 generic_fillattr(dentry->d_inode, stat);
 763
 764         kfree(st);
 765         return 0;
 766 }
 767
 768 /**
 769  * v9fs_vfs_setattr - set file metadata
 770  * @dentry: file whose metadata to set
 771  * @iattr: metadata assignment structure
 772  *
 773  */
 774
 775 static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
 776 {
 777         int retval;
 778         struct v9fs_session_info *v9ses;
 779         struct p9_fid *fid;
 780         struct p9_wstat wstat;
 781
 782         P9_DPRINTK(P9_DEBUG_VFS, "\n");
 783         retval = -EPERM;
 784         v9ses = v9fs_inode2v9ses(dentry->d_inode);
 785         fid = v9fs_fid_lookup(dentry);
 786         if(IS_ERR(fid))
 787                 return PTR_ERR(fid);
 788
 789         v9fs_blank_wstat(&wstat);
 790         if (iattr->ia_valid & ATTR_MODE)
 791                 wstat.mode = unixmode2p9mode(v9ses, iattr->ia_mode);
 792
 793         if (iattr->ia_valid & ATTR_MTIME)
 794                 wstat.mtime = iattr->ia_mtime.tv_sec;
 795
 796         if (iattr->ia_valid & ATTR_ATIME)
 797                 wstat.atime = iattr->ia_atime.tv_sec;
 798
 799         if (iattr->ia_valid & ATTR_SIZE)
 800                 wstat.length = iattr->ia_size;
 801
 802         if (v9fs_extended(v9ses)) {
 803                 if (iattr->ia_valid & ATTR_UID)
 804                         wstat.n_uid = iattr->ia_uid;
 805
 806                 if (iattr->ia_valid & ATTR_GID)
 807                         wstat.n_gid = iattr->ia_gid;
 808         }
 809
 810         retval = p9_client_wstat(fid, &wstat);
 811         if (retval >= 0)
 812                 retval = inode_setattr(dentry->d_inode, iattr);
 813
 814         return retval;
 815 }
 816
 817 /**
 818  * v9fs_stat2inode - populate an inode structure with mistat info
 819  * @stat: Plan 9 metadata (mistat) structure
 820  * @inode: inode to populate
 821  * @sb: superblock of filesystem
 822  *
 823  */
 824
 825 void
 826 v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode,
 827         struct super_block *sb)
 828 {
 829         char ext[32];
 830         struct v9fs_session_info *v9ses = sb->s_fs_info;
 831
 832         inode->i_nlink = 1;
 833
 834         inode->i_atime.tv_sec = stat->atime;
 835         inode->i_mtime.tv_sec = stat->mtime;
 836         inode->i_ctime.tv_sec = stat->mtime;
 837
 838         inode->i_uid = v9ses->dfltuid;
 839         inode->i_gid = v9ses->dfltgid;
 840
 841         if (v9fs_extended(v9ses)) {
 842                 inode->i_uid = stat->n_uid;
 843                 inode->i_gid = stat->n_gid;
 844         }
 845
 846         inode->i_mode = p9mode2unixmode(v9ses, stat->mode);
 847         if ((S_ISBLK(inode->i_mode)) || (S_ISCHR(inode->i_mode))) {
 848                 char type = 0;
 849                 int major = -1;
 850                 int minor = -1;
 851
 852                 strncpy(ext, stat->extension, sizeof(ext));
 853                 sscanf(ext, "%c %u %u", &type, &major, &minor);
 854                 switch (type) {
 855                 case 'c':
 856                         inode->i_mode &= ~S_IFBLK;
 857                         inode->i_mode |= S_IFCHR;
 858                         break;
 859                 case 'b':
 860                         break;
 861                 default:
 862                         P9_DPRINTK(P9_DEBUG_ERROR,
 863                                 "Unknown special type %c %s\n", type,
 864                                 stat->extension);
 865                 };
 866                 inode->i_rdev = MKDEV(major, minor);
 867                 init_special_inode(inode, inode->i_mode, inode->i_rdev);
 868         } else
 869                 inode->i_rdev = 0;
 870
 871         inode->i_size = stat->length;
 872
 873         /* not real number of blocks, but 512 byte ones ... */
 874         inode->i_blocks = (inode->i_size + 512 - 1) >> 9;
 875 }
 876
 877 /**
 878  * v9fs_qid2ino - convert qid into inode number
 879  * @qid: qid to hash
 880  *
 881  * BUG: potential for inode number collisions?
 882  */
 883
 884 ino_t v9fs_qid2ino(struct p9_qid *qid)
 885 {
 886         u64 path = qid->path + 2;
 887         ino_t i = 0;
 888
 889         if (sizeof(ino_t) == sizeof(path))
 890                 memcpy(&i, &path, sizeof(ino_t));
 891         else
 892                 i = (ino_t) (path ^ (path >> 32));
 893
 894         return i;
 895 }
 896
 897 /**
 898  * v9fs_readlink - read a symlink's location (internal version)
 899  * @dentry: dentry for symlink
 900  * @buffer: buffer to load symlink location into
 901  * @buflen: length of buffer
 902  *
 903  */
 904
 905 static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen)
 906 {
 907         int retval;
 908
 909         struct v9fs_session_info *v9ses;
 910         struct p9_fid *fid;
 911         struct p9_wstat *st;
 912
 913         P9_DPRINTK(P9_DEBUG_VFS, " %s\n", dentry->d_name.name);
 914         retval = -EPERM;
 915         v9ses = v9fs_inode2v9ses(dentry->d_inode);
 916         fid = v9fs_fid_lookup(dentry);
 917         if (IS_ERR(fid))
 918                 return PTR_ERR(fid);
 919
 920         if (!v9fs_extended(v9ses))
 921                 return -EBADF;
 922
 923         st = p9_client_stat(fid);
 924         if (IS_ERR(st))
 925                 return PTR_ERR(st);
 926
 927         if (!(st->mode & P9_DMSYMLINK)) {
 928                 retval = -EINVAL;
 929                 goto done;
 930         }
 931
 932         /* copy extension buffer into buffer */
 933         strncpy(buffer, st->extension, buflen);
 934
 935         P9_DPRINTK(P9_DEBUG_VFS,
 936                 "%s -> %s (%s)\n", dentry->d_name.name, st->extension, buffer);
 937
 938         retval = buflen;
 939
 940 done:
 941         kfree(st);
 942         return retval;
 943 }
 944
 945 /**
 946  * v9fs_vfs_readlink - read a symlink's location
 947  * @dentry: dentry for symlink
 948  * @buffer: buffer to load symlink location into
 949  * @buflen: length of buffer
 950  *
 951  */
 952
 953 static int v9fs_vfs_readlink(struct dentry *dentry, char __user * buffer,
 954                              int buflen)
 955 {
 956         int retval;
 957         int ret;
 958         char *link = __getname();
 959
 960         if (unlikely(!link))
 961                 return -ENOMEM;
 962
 963         if (buflen > PATH_MAX)
 964                 buflen = PATH_MAX;
 965
 966         P9_DPRINTK(P9_DEBUG_VFS, " dentry: %s (%p)\n", dentry->d_name.name,
 967                                                                         dentry);
 968
 969         retval = v9fs_readlink(dentry, link, buflen);
 970
 971         if (retval > 0) {
 972                 if ((ret = copy_to_user(buffer, link, retval)) != 0) {
 973                         P9_DPRINTK(P9_DEBUG_ERROR,
 974                                         "problem copying to user: %d\n", ret);
 975                         retval = ret;
 976                 }
 977         }
 978
 979         __putname(link);
 980         return retval;
 981 }
 982
 983 /**
 984  * v9fs_vfs_follow_link - follow a symlink path
 985  * @dentry: dentry for symlink
 986  * @nd: nameidata
 987  *
 988  */
 989
 990 static void *v9fs_vfs_follow_link(struct dentry *dentry, struct nameidata *nd)
 991 {
 992         int len = 0;
 993         char *link = __getname();
 994
 995         P9_DPRINTK(P9_DEBUG_VFS, "%s n", dentry->d_name.name);
 996
 997         if (!link)
 998                 link = ERR_PTR(-ENOMEM);
 999         else {
1000                 len = v9fs_readlink(dentry, link, PATH_MAX);
1001
1002                 if (len < 0) {
1003                         __putname(link);
1004                         link = ERR_PTR(len);
1005                 } else
1006                         link[len] = 0;
1007         }
1008         nd_set_link(nd, link);
1009
1010         return NULL;
1011 }
1012
1013 /**
1014  * v9fs_vfs_put_link - release a symlink path
1015  * @dentry: dentry for symlink
1016  * @nd: nameidata
1017  * @p: unused
1018  *
1019  */
1020
1021 static void
1022 v9fs_vfs_put_link(struct dentry *dentry, struct nameidata *nd, void *p)
1023 {
1024         char *s = nd_get_link(nd);
1025
1026         P9_DPRINTK(P9_DEBUG_VFS, " %s %s\n", dentry->d_name.name,
1027                 IS_ERR(s) ? "<error>" : s);
1028         if (!IS_ERR(s))
1029                 __putname(s);
1030 }
1031
1032 /**
1033  * v9fs_vfs_mkspecial - create a special file
1034  * @dir: inode to create special file in
1035  * @dentry: dentry to create
1036  * @mode: mode to create special file
1037  * @extension: 9p2000.u format extension string representing special file
1038  *
1039  */
1040
1041 static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry,
1042         int mode, const char *extension)
1043 {
1044         u32 perm;
1045         struct v9fs_session_info *v9ses;
1046         struct p9_fid *fid;
1047
1048         v9ses = v9fs_inode2v9ses(dir);
1049         if (!v9fs_extended(v9ses)) {
1050                 P9_DPRINTK(P9_DEBUG_ERROR, "not extended\n");
1051                 return -EPERM;
1052         }
1053
1054         perm = unixmode2p9mode(v9ses, mode);
1055         fid = v9fs_create(v9ses, dir, dentry, (char *) extension, perm,
1056                                                                 P9_OREAD);
1057         if (IS_ERR(fid))
1058                 return PTR_ERR(fid);
1059
1060         p9_client_clunk(fid);
1061         return 0;
1062 }
1063
1064 /**
1065  * v9fs_vfs_symlink - helper function to create symlinks
1066  * @dir: directory inode containing symlink
1067  * @dentry: dentry for symlink
1068  * @symname: symlink data
1069  *
1070  * See Also: 9P2000.u RFC for more information
1071  *
1072  */
1073
1074 static int
1075 v9fs_vfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
1076 {
1077         P9_DPRINTK(P9_DEBUG_VFS, " %lu,%s,%s\n", dir->i_ino,
1078                                         dentry->d_name.name, symname);
1079
1080         return v9fs_vfs_mkspecial(dir, dentry, S_IFLNK, symname);
1081 }
1082
1083 /**
1084  * v9fs_vfs_link - create a hardlink
1085  * @old_dentry: dentry for file to link to
1086  * @dir: inode destination for new link
1087  * @dentry: dentry for link
1088  *
1089  */
1090
1091 static int
1092 v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir,
1093               struct dentry *dentry)
1094 {
1095         int retval;
1096         struct p9_fid *oldfid;
1097         char *name;
1098
1099         P9_DPRINTK(P9_DEBUG_VFS,
1100                 " %lu,%s,%s\n", dir->i_ino, dentry->d_name.name,
1101                 old_dentry->d_name.name);
1102
1103         oldfid = v9fs_fid_clone(old_dentry);
1104         if (IS_ERR(oldfid))
1105                 return PTR_ERR(oldfid);
1106
1107         name = __getname();
1108         if (unlikely(!name)) {
1109                 retval = -ENOMEM;
1110                 goto clunk_fid;
1111         }
1112
1113         sprintf(name, "%d\n", oldfid->fid);
1114         retval = v9fs_vfs_mkspecial(dir, dentry, P9_DMLINK, name);
1115         __putname(name);
1116
1117 clunk_fid:
1118         p9_client_clunk(oldfid);
1119         return retval;
1120 }
1121
1122 /**
1123  * v9fs_vfs_mknod - create a special file
1124  * @dir: inode destination for new link
1125  * @dentry: dentry for file
1126  * @mode: mode for creation
1127  * @rdev: device associated with special file
1128  *
1129  */
1130
1131 static int
1132 v9fs_vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev)
1133 {
1134         int retval;
1135         char *name;
1136
1137         P9_DPRINTK(P9_DEBUG_VFS,
1138                 " %lu,%s mode: %x MAJOR: %u MINOR: %u\n", dir->i_ino,
1139                 dentry->d_name.name, mode, MAJOR(rdev), MINOR(rdev));
1140
1141         if (!new_valid_dev(rdev))
1142                 return -EINVAL;
1143
1144         name = __getname();
1145         if (!name)
1146                 return -ENOMEM;
1147         /* build extension */
1148         if (S_ISBLK(mode))
1149                 sprintf(name, "b %u %u", MAJOR(rdev), MINOR(rdev));
1150         else if (S_ISCHR(mode))
1151                 sprintf(name, "c %u %u", MAJOR(rdev), MINOR(rdev));
1152         else if (S_ISFIFO(mode))
1153                 *name = 0;
1154         else {
1155                 __putname(name);
1156                 return -EINVAL;
1157         }
1158
1159         retval = v9fs_vfs_mkspecial(dir, dentry, mode, name);
1160         __putname(name);
1161
1162         return retval;
1163 }
1164
1165 static const struct inode_operations v9fs_dir_inode_operations_ext = {
1166         .create = v9fs_vfs_create,
1167         .lookup = v9fs_vfs_lookup,
1168         .symlink = v9fs_vfs_symlink,
1169         .link = v9fs_vfs_link,
1170         .unlink = v9fs_vfs_unlink,
1171         .mkdir = v9fs_vfs_mkdir,
1172         .rmdir = v9fs_vfs_rmdir,
1173         .mknod = v9fs_vfs_mknod,
1174         .rename = v9fs_vfs_rename,
1175         .readlink = v9fs_vfs_readlink,
1176         .getattr = v9fs_vfs_getattr,
1177         .setattr = v9fs_vfs_setattr,
1178 };
1179
1180 static const struct inode_operations v9fs_dir_inode_operations = {
1181         .create = v9fs_vfs_create,
1182         .lookup = v9fs_vfs_lookup,
1183         .unlink = v9fs_vfs_unlink,
1184         .mkdir = v9fs_vfs_mkdir,
1185         .rmdir = v9fs_vfs_rmdir,
1186         .mknod = v9fs_vfs_mknod,
1187         .rename = v9fs_vfs_rename,
1188         .getattr = v9fs_vfs_getattr,
1189         .setattr = v9fs_vfs_setattr,
1190 };
1191
1192 static const struct inode_operations v9fs_file_inode_operations = {
1193         .getattr = v9fs_vfs_getattr,
1194         .setattr = v9fs_vfs_setattr,
1195 };
1196
1197 static const struct inode_operations v9fs_symlink_inode_operations = {
1198         .readlink = v9fs_vfs_readlink,
1199         .follow_link = v9fs_vfs_follow_link,
1200         .put_link = v9fs_vfs_put_link,
1201         .getattr = v9fs_vfs_getattr,
1202         .setattr = v9fs_vfs_setattr,
1203 };