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 <linux/slab.h>
  38 #include <net/9p/9p.h>
  39 #include <net/9p/client.h>
  40
  41 #include "v9fs.h"
  42 #include "v9fs_vfs.h"
  43 #include "fid.h"
  44 #include "cache.h"
  45
  46 static const struct inode_operations v9fs_dir_inode_operations;
  47 static const struct inode_operations v9fs_dir_inode_operations_dotu;
  48 static const struct inode_operations v9fs_dir_inode_operations_dotl;
  49 static const struct inode_operations v9fs_file_inode_operations;
  50 static const struct inode_operations v9fs_file_inode_operations_dotl;
  51 static const struct inode_operations v9fs_symlink_inode_operations;
  52 static const struct inode_operations v9fs_symlink_inode_operations_dotl;
  53
  54 /**
  55  * unixmode2p9mode - convert unix mode bits to plan 9
  56  * @v9ses: v9fs session information
  57  * @mode: mode to convert
  58  *
  59  */
  60
  61 static int unixmode2p9mode(struct v9fs_session_info *v9ses, int mode)
  62 {
  63         int res;
  64         res = mode & 0777;
  65         if (S_ISDIR(mode))
  66                 res |= P9_DMDIR;
  67         if (v9fs_proto_dotu(v9ses)) {
  68                 if (S_ISLNK(mode))
  69                         res |= P9_DMSYMLINK;
  70                 if (v9ses->nodev == 0) {
  71                         if (S_ISSOCK(mode))
  72                                 res |= P9_DMSOCKET;
  73                         if (S_ISFIFO(mode))
  74                                 res |= P9_DMNAMEDPIPE;
  75                         if (S_ISBLK(mode))
  76                                 res |= P9_DMDEVICE;
  77                         if (S_ISCHR(mode))
  78                                 res |= P9_DMDEVICE;
  79                 }
  80
  81                 if ((mode & S_ISUID) == S_ISUID)
  82                         res |= P9_DMSETUID;
  83                 if ((mode & S_ISGID) == S_ISGID)
  84                         res |= P9_DMSETGID;
  85                 if ((mode & S_ISVTX) == S_ISVTX)
  86                         res |= P9_DMSETVTX;
  87                 if ((mode & P9_DMLINK))
  88                         res |= P9_DMLINK;
  89         }
  90
  91         return res;
  92 }
  93
  94 /**
  95  * p9mode2unixmode- convert plan9 mode bits to unix mode bits
  96  * @v9ses: v9fs session information
  97  * @mode: mode to convert
  98  *
  99  */
 100
 101 static int p9mode2unixmode(struct v9fs_session_info *v9ses, int mode)
 102 {
 103         int res;
 104
 105         res = mode & 0777;
 106
 107         if ((mode & P9_DMDIR) == P9_DMDIR)
 108                 res |= S_IFDIR;
 109         else if ((mode & P9_DMSYMLINK) && (v9fs_proto_dotu(v9ses)))
 110                 res |= S_IFLNK;
 111         else if ((mode & P9_DMSOCKET) && (v9fs_proto_dotu(v9ses))
 112                  && (v9ses->nodev == 0))
 113                 res |= S_IFSOCK;
 114         else if ((mode & P9_DMNAMEDPIPE) && (v9fs_proto_dotu(v9ses))
 115                  && (v9ses->nodev == 0))
 116                 res |= S_IFIFO;
 117         else if ((mode & P9_DMDEVICE) && (v9fs_proto_dotu(v9ses))
 118                  && (v9ses->nodev == 0))
 119                 res |= S_IFBLK;
 120         else
 121                 res |= S_IFREG;
 122
 123         if (v9fs_proto_dotu(v9ses)) {
 124                 if ((mode & P9_DMSETUID) == P9_DMSETUID)
 125                         res |= S_ISUID;
 126
 127                 if ((mode & P9_DMSETGID) == P9_DMSETGID)
 128                         res |= S_ISGID;
 129
 130                 if ((mode & P9_DMSETVTX) == P9_DMSETVTX)
 131                         res |= S_ISVTX;
 132         }
 133
 134         return res;
 135 }
 136
 137 /**
 138  * v9fs_uflags2omode- convert posix open flags to plan 9 mode bits
 139  * @uflags: flags to convert
 140  * @extended: if .u extensions are active
 141  */
 142
 143 int v9fs_uflags2omode(int uflags, int extended)
 144 {
 145         int ret;
 146
 147         ret = 0;
 148         switch (uflags&3) {
 149         default:
 150         case O_RDONLY:
 151                 ret = P9_OREAD;
 152                 break;
 153
 154         case O_WRONLY:
 155                 ret = P9_OWRITE;
 156                 break;
 157
 158         case O_RDWR:
 159                 ret = P9_ORDWR;
 160                 break;
 161         }
 162
 163         if (uflags & O_TRUNC)
 164                 ret |= P9_OTRUNC;
 165
 166         if (extended) {
 167                 if (uflags & O_EXCL)
 168                         ret |= P9_OEXCL;
 169
 170                 if (uflags & O_APPEND)
 171                         ret |= P9_OAPPEND;
 172         }
 173
 174         return ret;
 175 }
 176
 177 /**
 178  * v9fs_blank_wstat - helper function to setup a 9P stat structure
 179  * @wstat: structure to initialize
 180  *
 181  */
 182
 183 void
 184 v9fs_blank_wstat(struct p9_wstat *wstat)
 185 {
 186         wstat->type = ~0;
 187         wstat->dev = ~0;
 188         wstat->qid.type = ~0;
 189         wstat->qid.version = ~0;
 190         *((long long *)&wstat->qid.path) = ~0;
 191         wstat->mode = ~0;
 192         wstat->atime = ~0;
 193         wstat->mtime = ~0;
 194         wstat->length = ~0;
 195         wstat->name = NULL;
 196         wstat->uid = NULL;
 197         wstat->gid = NULL;
 198         wstat->muid = NULL;
 199         wstat->n_uid = ~0;
 200         wstat->n_gid = ~0;
 201         wstat->n_muid = ~0;
 202         wstat->extension = NULL;
 203 }
 204
 205 #ifdef CONFIG_9P_FSCACHE
 206 /**
 207  * v9fs_alloc_inode - helper function to allocate an inode
 208  * This callback is executed before setting up the inode so that we
 209  * can associate a vcookie with each inode.
 210  *
 211  */
 212
 213 struct inode *v9fs_alloc_inode(struct super_block *sb)
 214 {
 215         struct v9fs_cookie *vcookie;
 216         vcookie = (struct v9fs_cookie *)kmem_cache_alloc(vcookie_cache,
 217                                                          GFP_KERNEL);
 218         if (!vcookie)
 219                 return NULL;
 220
 221         vcookie->fscache = NULL;
 222         vcookie->qid = NULL;
 223         spin_lock_init(&vcookie->lock);
 224         return &vcookie->inode;
 225 }
 226
 227 /**
 228  * v9fs_destroy_inode - destroy an inode
 229  *
 230  */
 231
 232 void v9fs_destroy_inode(struct inode *inode)
 233 {
 234         kmem_cache_free(vcookie_cache, v9fs_inode2cookie(inode));
 235 }
 236 #endif
 237
 238 /**
 239  * v9fs_get_inode - helper function to setup an inode
 240  * @sb: superblock
 241  * @mode: mode to setup inode with
 242  *
 243  */
 244
 245 struct inode *v9fs_get_inode(struct super_block *sb, int mode)
 246 {
 247         int err;
 248         struct inode *inode;
 249         struct v9fs_session_info *v9ses = sb->s_fs_info;
 250
 251         P9_DPRINTK(P9_DEBUG_VFS, "super block: %p mode: %o\n", sb, mode);
 252
 253         inode = new_inode(sb);
 254         if (!inode) {
 255                 P9_EPRINTK(KERN_WARNING, "Problem allocating inode\n");
 256                 return ERR_PTR(-ENOMEM);
 257         }
 258
 259         inode_init_owner(inode, NULL, mode);
 260         inode->i_blocks = 0;
 261         inode->i_rdev = 0;
 262         inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
 263         inode->i_mapping->a_ops = &v9fs_addr_operations;
 264
 265         switch (mode & S_IFMT) {
 266         case S_IFIFO:
 267         case S_IFBLK:
 268         case S_IFCHR:
 269         case S_IFSOCK:
 270                 if (!v9fs_proto_dotu(v9ses)) {
 271                         P9_DPRINTK(P9_DEBUG_ERROR,
 272                                    "special files without extended mode\n");
 273                         err = -EINVAL;
 274                         goto error;
 275                 }
 276                 init_special_inode(inode, inode->i_mode, inode->i_rdev);
 277                 break;
 278         case S_IFREG:
 279                 if (v9fs_proto_dotl(v9ses)) {
 280                         inode->i_op = &v9fs_file_inode_operations_dotl;
 281                         inode->i_fop = &v9fs_file_operations_dotl;
 282                 } else {
 283                         inode->i_op = &v9fs_file_inode_operations;
 284                         inode->i_fop = &v9fs_file_operations;
 285                 }
 286
 287                 break;
 288
 289         case S_IFLNK:
 290                 if (!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses)) {
 291                         P9_DPRINTK(P9_DEBUG_ERROR, "extended modes used with "
 292                                                 "legacy protocol.\n");
 293                         err = -EINVAL;
 294                         goto error;
 295                 }
 296
 297                 if (v9fs_proto_dotl(v9ses))
 298                         inode->i_op = &v9fs_symlink_inode_operations_dotl;
 299                 else
 300                         inode->i_op = &v9fs_symlink_inode_operations;
 301
 302                 break;
 303         case S_IFDIR:
 304                 inc_nlink(inode);
 305                 if (v9fs_proto_dotl(v9ses))
 306                         inode->i_op = &v9fs_dir_inode_operations_dotl;
 307                 else if (v9fs_proto_dotu(v9ses))
 308                         inode->i_op = &v9fs_dir_inode_operations_dotu;
 309                 else
 310                         inode->i_op = &v9fs_dir_inode_operations;
 311
 312                 if (v9fs_proto_dotl(v9ses))
 313                         inode->i_fop = &v9fs_dir_operations_dotl;
 314                 else
 315                         inode->i_fop = &v9fs_dir_operations;
 316
 317                 break;
 318         default:
 319                 P9_DPRINTK(P9_DEBUG_ERROR, "BAD mode 0x%x S_IFMT 0x%x\n",
 320                            mode, mode & S_IFMT);
 321                 err = -EINVAL;
 322                 goto error;
 323         }
 324
 325         return inode;
 326
 327 error:
 328         iput(inode);
 329         return ERR_PTR(err);
 330 }
 331
 332 /*
 333 static struct v9fs_fid*
 334 v9fs_clone_walk(struct v9fs_session_info *v9ses, u32 fid, struct dentry *dentry)
 335 {
 336         int err;
 337         int nfid;
 338         struct v9fs_fid *ret;
 339         struct v9fs_fcall *fcall;
 340
 341         nfid = v9fs_get_idpool(&v9ses->fidpool);
 342         if (nfid < 0) {
 343                 eprintk(KERN_WARNING, "no free fids available\n");
 344                 return ERR_PTR(-ENOSPC);
 345         }
 346
 347         err = v9fs_t_walk(v9ses, fid, nfid, (char *) dentry->d_name.name,
 348                 &fcall);
 349
 350         if (err < 0) {
 351                 if (fcall && fcall->id == RWALK)
 352                         goto clunk_fid;
 353
 354                 PRINT_FCALL_ERROR("walk error", fcall);
 355                 v9fs_put_idpool(nfid, &v9ses->fidpool);
 356                 goto error;
 357         }
 358
 359         kfree(fcall);
 360         fcall = NULL;
 361         ret = v9fs_fid_create(v9ses, nfid);
 362         if (!ret) {
 363                 err = -ENOMEM;
 364                 goto clunk_fid;
 365         }
 366
 367         err = v9fs_fid_insert(ret, dentry);
 368         if (err < 0) {
 369                 v9fs_fid_destroy(ret);
 370                 goto clunk_fid;
 371         }
 372
 373         return ret;
 374
 375 clunk_fid:
 376         v9fs_t_clunk(v9ses, nfid);
 377
 378 error:
 379         kfree(fcall);
 380         return ERR_PTR(err);
 381 }
 382 */
 383
 384
 385 /**
 386  * v9fs_clear_inode - release an inode
 387  * @inode: inode to release
 388  *
 389  */
 390 void v9fs_clear_inode(struct inode *inode)
 391 {
 392         filemap_fdatawrite(inode->i_mapping);
 393
 394 #ifdef CONFIG_9P_FSCACHE
 395         v9fs_cache_inode_put_cookie(inode);
 396 #endif
 397 }
 398
 399 static struct inode *
 400 v9fs_inode(struct v9fs_session_info *v9ses, struct p9_fid *fid,
 401         struct super_block *sb)
 402 {
 403         int err, umode;
 404         struct inode *ret = NULL;
 405         struct p9_wstat *st;
 406
 407         st = p9_client_stat(fid);
 408         if (IS_ERR(st))
 409                 return ERR_CAST(st);
 410
 411         umode = p9mode2unixmode(v9ses, st->mode);
 412         ret = v9fs_get_inode(sb, umode);
 413         if (IS_ERR(ret)) {
 414                 err = PTR_ERR(ret);
 415                 goto error;
 416         }
 417
 418         v9fs_stat2inode(st, ret, sb);
 419         ret->i_ino = v9fs_qid2ino(&st->qid);
 420
 421 #ifdef CONFIG_9P_FSCACHE
 422         v9fs_vcookie_set_qid(ret, &st->qid);
 423         v9fs_cache_inode_get_cookie(ret);
 424 #endif
 425         p9stat_free(st);
 426         kfree(st);
 427         return ret;
 428 error:
 429         p9stat_free(st);
 430         kfree(st);
 431         return ERR_PTR(err);
 432 }
 433
 434 static struct inode *
 435 v9fs_inode_dotl(struct v9fs_session_info *v9ses, struct p9_fid *fid,
 436         struct super_block *sb)
 437 {
 438         struct inode *ret = NULL;
 439         int err;
 440         struct p9_stat_dotl *st;
 441
 442         st = p9_client_getattr_dotl(fid, P9_STATS_BASIC);
 443         if (IS_ERR(st))
 444                 return ERR_CAST(st);
 445
 446         ret = v9fs_get_inode(sb, st->st_mode);
 447         if (IS_ERR(ret)) {
 448                 err = PTR_ERR(ret);
 449                 goto error;
 450         }
 451
 452         v9fs_stat2inode_dotl(st, ret);
 453         ret->i_ino = v9fs_qid2ino(&st->qid);
 454 #ifdef CONFIG_9P_FSCACHE
 455         v9fs_vcookie_set_qid(ret, &st->qid);
 456         v9fs_cache_inode_get_cookie(ret);
 457 #endif
 458         kfree(st);
 459         return ret;
 460 error:
 461         kfree(st);
 462         return ERR_PTR(err);
 463 }
 464
 465 /**
 466  * v9fs_inode_from_fid - Helper routine to populate an inode by
 467  * issuing a attribute request
 468  * @v9ses: session information
 469  * @fid: fid to issue attribute request for
 470  * @sb: superblock on which to create inode
 471  *
 472  */
 473 static inline struct inode *
 474 v9fs_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
 475                         struct super_block *sb)
 476 {
 477         if (v9fs_proto_dotl(v9ses))
 478                 return v9fs_inode_dotl(v9ses, fid, sb);
 479         else
 480                 return v9fs_inode(v9ses, fid, sb);
 481 }
 482
 483 /**
 484  * v9fs_remove - helper function to remove files and directories
 485  * @dir: directory inode that is being deleted
 486  * @file:  dentry that is being deleted
 487  * @rmdir: removing a directory
 488  *
 489  */
 490
 491 static int v9fs_remove(struct inode *dir, struct dentry *file, int rmdir)
 492 {
 493         int retval;
 494         struct inode *file_inode;
 495         struct p9_fid *v9fid;
 496
 497         P9_DPRINTK(P9_DEBUG_VFS, "inode: %p dentry: %p rmdir: %d\n", dir, file,
 498                 rmdir);
 499
 500         file_inode = file->d_inode;
 501         v9fid = v9fs_fid_clone(file);
 502         if (IS_ERR(v9fid))
 503                 return PTR_ERR(v9fid);
 504
 505         retval = p9_client_remove(v9fid);
 506         if (!retval)
 507                 drop_nlink(file_inode);
 508         return retval;
 509 }
 510
 511 static int
 512 v9fs_open_created(struct inode *inode, struct file *file)
 513 {
 514         return 0;
 515 }
 516
 517
 518 /**
 519  * v9fs_create - Create a file
 520  * @v9ses: session information
 521  * @dir: directory that dentry is being created in
 522  * @dentry:  dentry that is being created
 523  * @extension: 9p2000.u extension string to support devices, etc.
 524  * @perm: create permissions
 525  * @mode: open mode
 526  *
 527  */
 528 static struct p9_fid *
 529 v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
 530                 struct dentry *dentry, char *extension, u32 perm, u8 mode)
 531 {
 532         int err;
 533         char *name;
 534         struct p9_fid *dfid, *ofid, *fid;
 535         struct inode *inode;
 536
 537         P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name);
 538
 539         err = 0;
 540         ofid = NULL;
 541         fid = NULL;
 542         name = (char *) dentry->d_name.name;
 543         dfid = v9fs_fid_lookup(dentry->d_parent);
 544         if (IS_ERR(dfid)) {
 545                 err = PTR_ERR(dfid);
 546                 P9_DPRINTK(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
 547                 return ERR_PTR(err);
 548         }
 549
 550         /* clone a fid to use for creation */
 551         ofid = p9_client_walk(dfid, 0, NULL, 1);
 552         if (IS_ERR(ofid)) {
 553                 err = PTR_ERR(ofid);
 554                 P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
 555                 return ERR_PTR(err);
 556         }
 557
 558         err = p9_client_fcreate(ofid, name, perm, mode, extension);
 559         if (err < 0) {
 560                 P9_DPRINTK(P9_DEBUG_VFS, "p9_client_fcreate failed %d\n", err);
 561                 goto error;
 562         }
 563
 564         /* now walk from the parent so we can get unopened fid */
 565         fid = p9_client_walk(dfid, 1, &name, 1);
 566         if (IS_ERR(fid)) {
 567                 err = PTR_ERR(fid);
 568                 P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
 569                 fid = NULL;
 570                 goto error;
 571         }
 572
 573         /* instantiate inode and assign the unopened fid to the dentry */
 574         inode = v9fs_inode_from_fid(v9ses, fid, dir->i_sb);
 575         if (IS_ERR(inode)) {
 576                 err = PTR_ERR(inode);
 577                 P9_DPRINTK(P9_DEBUG_VFS, "inode creation failed %d\n", err);
 578                 goto error;
 579         }
 580
 581         if (v9ses->cache)
 582                 dentry->d_op = &v9fs_cached_dentry_operations;
 583         else
 584                 dentry->d_op = &v9fs_dentry_operations;
 585
 586         d_instantiate(dentry, inode);
 587         err = v9fs_fid_add(dentry, fid);
 588         if (err < 0)
 589                 goto error;
 590
 591         return ofid;
 592
 593 error:
 594         if (ofid)
 595                 p9_client_clunk(ofid);
 596
 597         if (fid)
 598                 p9_client_clunk(fid);
 599
 600         return ERR_PTR(err);
 601 }
 602
 603 /**
 604  * v9fs_vfs_create - VFS hook to create files
 605  * @dir: directory inode that is being created
 606  * @dentry:  dentry that is being deleted
 607  * @mode: create permissions
 608  * @nd: path information
 609  *
 610  */
 611
 612 static int
 613 v9fs_vfs_create(struct inode *dir, struct dentry *dentry, int mode,
 614                 struct nameidata *nd)
 615 {
 616         int err;
 617         u32 perm;
 618         int flags;
 619         struct v9fs_session_info *v9ses;
 620         struct p9_fid *fid;
 621         struct file *filp;
 622
 623         err = 0;
 624         fid = NULL;
 625         v9ses = v9fs_inode2v9ses(dir);
 626         perm = unixmode2p9mode(v9ses, mode);
 627         if (nd && nd->flags & LOOKUP_OPEN)
 628                 flags = nd->intent.open.flags - 1;
 629         else
 630                 flags = O_RDWR;
 631
 632         fid = v9fs_create(v9ses, dir, dentry, NULL, perm,
 633                                 v9fs_uflags2omode(flags,
 634                                                 v9fs_proto_dotu(v9ses)));
 635         if (IS_ERR(fid)) {
 636                 err = PTR_ERR(fid);
 637                 fid = NULL;
 638                 goto error;
 639         }
 640
 641         /* if we are opening a file, assign the open fid to the file */
 642         if (nd && nd->flags & LOOKUP_OPEN) {
 643                 filp = lookup_instantiate_filp(nd, dentry, v9fs_open_created);
 644                 if (IS_ERR(filp)) {
 645                         err = PTR_ERR(filp);
 646                         goto error;
 647                 }
 648
 649                 filp->private_data = fid;
 650         } else
 651                 p9_client_clunk(fid);
 652
 653         return 0;
 654
 655 error:
 656         if (fid)
 657                 p9_client_clunk(fid);
 658
 659         return err;
 660 }
 661
 662 /**
 663  * v9fs_vfs_mkdir - VFS mkdir hook to create a directory
 664  * @dir:  inode that is being unlinked
 665  * @dentry: dentry that is being unlinked
 666  * @mode: mode for new directory
 667  *
 668  */
 669
 670 static int v9fs_vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 671 {
 672         int err;
 673         u32 perm;
 674         struct v9fs_session_info *v9ses;
 675         struct p9_fid *fid;
 676
 677         P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name);
 678         err = 0;
 679         v9ses = v9fs_inode2v9ses(dir);
 680         perm = unixmode2p9mode(v9ses, mode | S_IFDIR);
 681         fid = v9fs_create(v9ses, dir, dentry, NULL, perm, P9_OREAD);
 682         if (IS_ERR(fid)) {
 683                 err = PTR_ERR(fid);
 684                 fid = NULL;
 685         }
 686
 687         if (fid)
 688                 p9_client_clunk(fid);
 689
 690         return err;
 691 }
 692
 693 /**
 694  * v9fs_vfs_lookup - VFS lookup hook to "walk" to a new inode
 695  * @dir:  inode that is being walked from
 696  * @dentry: dentry that is being walked to?
 697  * @nameidata: path data
 698  *
 699  */
 700
 701 static struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
 702                                       struct nameidata *nameidata)
 703 {
 704         struct super_block *sb;
 705         struct v9fs_session_info *v9ses;
 706         struct p9_fid *dfid, *fid;
 707         struct inode *inode;
 708         char *name;
 709         int result = 0;
 710
 711         P9_DPRINTK(P9_DEBUG_VFS, "dir: %p dentry: (%s) %p nameidata: %p\n",
 712                 dir, dentry->d_name.name, dentry, nameidata);
 713
 714         if (dentry->d_name.len > NAME_MAX)
 715                 return ERR_PTR(-ENAMETOOLONG);
 716
 717         sb = dir->i_sb;
 718         v9ses = v9fs_inode2v9ses(dir);
 719         dfid = v9fs_fid_lookup(dentry->d_parent);
 720         if (IS_ERR(dfid))
 721                 return ERR_CAST(dfid);
 722
 723         name = (char *) dentry->d_name.name;
 724         fid = p9_client_walk(dfid, 1, &name, 1);
 725         if (IS_ERR(fid)) {
 726                 result = PTR_ERR(fid);
 727                 if (result == -ENOENT) {
 728                         inode = NULL;
 729                         goto inst_out;
 730                 }
 731
 732                 return ERR_PTR(result);
 733         }
 734
 735         inode = v9fs_inode_from_fid(v9ses, fid, dir->i_sb);
 736         if (IS_ERR(inode)) {
 737                 result = PTR_ERR(inode);
 738                 inode = NULL;
 739                 goto error;
 740         }
 741
 742         result = v9fs_fid_add(dentry, fid);
 743         if (result < 0)
 744                 goto error;
 745
 746 inst_out:
 747         if (v9ses->cache)
 748                 dentry->d_op = &v9fs_cached_dentry_operations;
 749         else
 750                 dentry->d_op = &v9fs_dentry_operations;
 751
 752         d_add(dentry, inode);
 753         return NULL;
 754
 755 error:
 756         p9_client_clunk(fid);
 757
 758         return ERR_PTR(result);
 759 }
 760
 761 /**
 762  * v9fs_vfs_unlink - VFS unlink hook to delete an inode
 763  * @i:  inode that is being unlinked
 764  * @d: dentry that is being unlinked
 765  *
 766  */
 767
 768 static int v9fs_vfs_unlink(struct inode *i, struct dentry *d)
 769 {
 770         return v9fs_remove(i, d, 0);
 771 }
 772
 773 /**
 774  * v9fs_vfs_rmdir - VFS unlink hook to delete a directory
 775  * @i:  inode that is being unlinked
 776  * @d: dentry that is being unlinked
 777  *
 778  */
 779
 780 static int v9fs_vfs_rmdir(struct inode *i, struct dentry *d)
 781 {
 782         return v9fs_remove(i, d, 1);
 783 }
 784
 785 /**
 786  * v9fs_vfs_rename - VFS hook to rename an inode
 787  * @old_dir:  old dir inode
 788  * @old_dentry: old dentry
 789  * @new_dir: new dir inode
 790  * @new_dentry: new dentry
 791  *
 792  */
 793
 794 static int
 795 v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 796                 struct inode *new_dir, struct dentry *new_dentry)
 797 {
 798         struct inode *old_inode;
 799         struct v9fs_session_info *v9ses;
 800         struct p9_fid *oldfid;
 801         struct p9_fid *olddirfid;
 802         struct p9_fid *newdirfid;
 803         struct p9_wstat wstat;
 804         int retval;
 805
 806         P9_DPRINTK(P9_DEBUG_VFS, "\n");
 807         retval = 0;
 808         old_inode = old_dentry->d_inode;
 809         v9ses = v9fs_inode2v9ses(old_inode);
 810         oldfid = v9fs_fid_lookup(old_dentry);
 811         if (IS_ERR(oldfid))
 812                 return PTR_ERR(oldfid);
 813
 814         olddirfid = v9fs_fid_clone(old_dentry->d_parent);
 815         if (IS_ERR(olddirfid)) {
 816                 retval = PTR_ERR(olddirfid);
 817                 goto done;
 818         }
 819
 820         newdirfid = v9fs_fid_clone(new_dentry->d_parent);
 821         if (IS_ERR(newdirfid)) {
 822                 retval = PTR_ERR(newdirfid);
 823                 goto clunk_olddir;
 824         }
 825
 826         if (v9fs_proto_dotl(v9ses)) {
 827                 retval = p9_client_rename(oldfid, newdirfid,
 828                                         (char *) new_dentry->d_name.name);
 829                 if (retval != -ENOSYS)
 830                         goto clunk_newdir;
 831         }
 832
 833         /* 9P can only handle file rename in the same directory */
 834         if (memcmp(&olddirfid->qid, &newdirfid->qid, sizeof(newdirfid->qid))) {
 835                 P9_DPRINTK(P9_DEBUG_ERROR,
 836                                 "old dir and new dir are different\n");
 837                 retval = -EXDEV;
 838                 goto clunk_newdir;
 839         }
 840
 841         v9fs_blank_wstat(&wstat);
 842         wstat.muid = v9ses->uname;
 843         wstat.name = (char *) new_dentry->d_name.name;
 844         retval = p9_client_wstat(oldfid, &wstat);
 845
 846 clunk_newdir:
 847         p9_client_clunk(newdirfid);
 848
 849 clunk_olddir:
 850         p9_client_clunk(olddirfid);
 851
 852 done:
 853         return retval;
 854 }
 855
 856 /**
 857  * v9fs_vfs_getattr - retrieve file metadata
 858  * @mnt: mount information
 859  * @dentry: file to get attributes on
 860  * @stat: metadata structure to populate
 861  *
 862  */
 863
 864 static int
 865 v9fs_vfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
 866                  struct kstat *stat)
 867 {
 868         int err;
 869         struct v9fs_session_info *v9ses;
 870         struct p9_fid *fid;
 871         struct p9_wstat *st;
 872
 873         P9_DPRINTK(P9_DEBUG_VFS, "dentry: %p\n", dentry);
 874         err = -EPERM;
 875         v9ses = v9fs_inode2v9ses(dentry->d_inode);
 876         if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
 877                 return simple_getattr(mnt, dentry, stat);
 878
 879         fid = v9fs_fid_lookup(dentry);
 880         if (IS_ERR(fid))
 881                 return PTR_ERR(fid);
 882
 883         st = p9_client_stat(fid);
 884         if (IS_ERR(st))
 885                 return PTR_ERR(st);
 886
 887         v9fs_stat2inode(st, dentry->d_inode, dentry->d_inode->i_sb);
 888                 generic_fillattr(dentry->d_inode, stat);
 889
 890         kfree(st);
 891         return 0;
 892 }
 893
 894 static int
 895 v9fs_vfs_getattr_dotl(struct vfsmount *mnt, struct dentry *dentry,
 896                  struct kstat *stat)
 897 {
 898         int err;
 899         struct v9fs_session_info *v9ses;
 900         struct p9_fid *fid;
 901         struct p9_stat_dotl *st;
 902
 903         P9_DPRINTK(P9_DEBUG_VFS, "dentry: %p\n", dentry);
 904         err = -EPERM;
 905         v9ses = v9fs_inode2v9ses(dentry->d_inode);
 906         if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
 907                 return simple_getattr(mnt, dentry, stat);
 908
 909         fid = v9fs_fid_lookup(dentry);
 910         if (IS_ERR(fid))
 911                 return PTR_ERR(fid);
 912
 913         /* Ask for all the fields in stat structure. Server will return
 914          * whatever it supports
 915          */
 916
 917         st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
 918         if (IS_ERR(st))
 919                 return PTR_ERR(st);
 920
 921         v9fs_stat2inode_dotl(st, dentry->d_inode);
 922         generic_fillattr(dentry->d_inode, stat);
 923         /* Change block size to what the server returned */
 924         stat->blksize = st->st_blksize;
 925
 926         kfree(st);
 927         return 0;
 928 }
 929
 930 /**
 931  * v9fs_vfs_setattr - set file metadata
 932  * @dentry: file whose metadata to set
 933  * @iattr: metadata assignment structure
 934  *
 935  */
 936
 937 static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
 938 {
 939         int retval;
 940         struct v9fs_session_info *v9ses;
 941         struct p9_fid *fid;
 942         struct p9_wstat wstat;
 943
 944         P9_DPRINTK(P9_DEBUG_VFS, "\n");
 945         retval = -EPERM;
 946         v9ses = v9fs_inode2v9ses(dentry->d_inode);
 947         fid = v9fs_fid_lookup(dentry);
 948         if(IS_ERR(fid))
 949                 return PTR_ERR(fid);
 950
 951         v9fs_blank_wstat(&wstat);
 952         if (iattr->ia_valid & ATTR_MODE)
 953                 wstat.mode = unixmode2p9mode(v9ses, iattr->ia_mode);
 954
 955         if (iattr->ia_valid & ATTR_MTIME)
 956                 wstat.mtime = iattr->ia_mtime.tv_sec;
 957
 958         if (iattr->ia_valid & ATTR_ATIME)
 959                 wstat.atime = iattr->ia_atime.tv_sec;
 960
 961         if (iattr->ia_valid & ATTR_SIZE)
 962                 wstat.length = iattr->ia_size;
 963
 964         if (v9fs_proto_dotu(v9ses)) {
 965                 if (iattr->ia_valid & ATTR_UID)
 966                         wstat.n_uid = iattr->ia_uid;
 967
 968                 if (iattr->ia_valid & ATTR_GID)
 969                         wstat.n_gid = iattr->ia_gid;
 970         }
 971
 972         retval = p9_client_wstat(fid, &wstat);
 973         if (retval >= 0)
 974                 retval = inode_setattr(dentry->d_inode, iattr);
 975
 976         return retval;
 977 }
 978
 979 /**
 980  * v9fs_vfs_setattr_dotl - set file metadata
 981  * @dentry: file whose metadata to set
 982  * @iattr: metadata assignment structure
 983  *
 984  */
 985
 986 static int v9fs_vfs_setattr_dotl(struct dentry *dentry, struct iattr *iattr)
 987 {
 988         int retval;
 989         struct v9fs_session_info *v9ses;
 990         struct p9_fid *fid;
 991         struct p9_iattr_dotl p9attr;
 992
 993         P9_DPRINTK(P9_DEBUG_VFS, "\n");
 994
 995         retval = inode_change_ok(dentry->d_inode, iattr);
 996         if (retval)
 997                 return retval;
 998
 999         p9attr.valid = iattr->ia_valid;
1000         p9attr.mode = iattr->ia_mode;
1001         p9attr.uid = iattr->ia_uid;
1002         p9attr.gid = iattr->ia_gid;
1003         p9attr.size = iattr->ia_size;
1004         p9attr.atime_sec = iattr->ia_atime.tv_sec;
1005         p9attr.atime_nsec = iattr->ia_atime.tv_nsec;
1006         p9attr.mtime_sec = iattr->ia_mtime.tv_sec;
1007         p9attr.mtime_nsec = iattr->ia_mtime.tv_nsec;
1008
1009         retval = -EPERM;
1010         v9ses = v9fs_inode2v9ses(dentry->d_inode);
1011         fid = v9fs_fid_lookup(dentry);
1012         if (IS_ERR(fid))
1013                 return PTR_ERR(fid);
1014
1015         retval = p9_client_setattr(fid, &p9attr);
1016         if (retval >= 0)
1017                 retval = inode_setattr(dentry->d_inode, iattr);
1018
1019         return retval;
1020 }
1021
1022 /**
1023  * v9fs_stat2inode - populate an inode structure with mistat info
1024  * @stat: Plan 9 metadata (mistat) structure
1025  * @inode: inode to populate
1026  * @sb: superblock of filesystem
1027  *
1028  */
1029
1030 void
1031 v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode,
1032         struct super_block *sb)
1033 {
1034         char ext[32];
1035         char tag_name[14];
1036         unsigned int i_nlink;
1037         struct v9fs_session_info *v9ses = sb->s_fs_info;
1038
1039         inode->i_nlink = 1;
1040
1041         inode->i_atime.tv_sec = stat->atime;
1042         inode->i_mtime.tv_sec = stat->mtime;
1043         inode->i_ctime.tv_sec = stat->mtime;
1044
1045         inode->i_uid = v9ses->dfltuid;
1046         inode->i_gid = v9ses->dfltgid;
1047
1048         if (v9fs_proto_dotu(v9ses)) {
1049                 inode->i_uid = stat->n_uid;
1050                 inode->i_gid = stat->n_gid;
1051         }
1052         if ((S_ISREG(inode->i_mode)) || (S_ISDIR(inode->i_mode))) {
1053                 if (v9fs_proto_dotu(v9ses) && (stat->extension[0] != '\0')) {
1054                         /*
1055                          * Hadlink support got added later to
1056                          * to the .u extension. So there can be
1057                          * server out there that doesn't support
1058                          * this even with .u extension. So check
1059                          * for non NULL stat->extension
1060                          */
1061                         strncpy(ext, stat->extension, sizeof(ext));
1062                         /* HARDLINKCOUNT %u */
1063                         sscanf(ext, "%13s %u", tag_name, &i_nlink);
1064                         if (!strncmp(tag_name, "HARDLINKCOUNT", 13))
1065                                 inode->i_nlink = i_nlink;
1066                 }
1067         }
1068         inode->i_mode = p9mode2unixmode(v9ses, stat->mode);
1069         if ((S_ISBLK(inode->i_mode)) || (S_ISCHR(inode->i_mode))) {
1070                 char type = 0;
1071                 int major = -1;
1072                 int minor = -1;
1073
1074                 strncpy(ext, stat->extension, sizeof(ext));
1075                 sscanf(ext, "%c %u %u", &type, &major, &minor);
1076                 switch (type) {
1077                 case 'c':
1078                         inode->i_mode &= ~S_IFBLK;
1079                         inode->i_mode |= S_IFCHR;
1080                         break;
1081                 case 'b':
1082                         break;
1083                 default:
1084                         P9_DPRINTK(P9_DEBUG_ERROR,
1085                                 "Unknown special type %c %s\n", type,
1086                                 stat->extension);
1087                 };
1088                 inode->i_rdev = MKDEV(major, minor);
1089                 init_special_inode(inode, inode->i_mode, inode->i_rdev);
1090         } else
1091                 inode->i_rdev = 0;
1092
1093         i_size_write(inode, stat->length);
1094
1095         /* not real number of blocks, but 512 byte ones ... */
1096         inode->i_blocks = (i_size_read(inode) + 512 - 1) >> 9;
1097 }
1098
1099 /**
1100  * v9fs_stat2inode_dotl - populate an inode structure with stat info
1101  * @stat: stat structure
1102  * @inode: inode to populate
1103  * @sb: superblock of filesystem
1104  *
1105  */
1106
1107 void
1108 v9fs_stat2inode_dotl(struct p9_stat_dotl *stat, struct inode *inode)
1109 {
1110
1111         if ((stat->st_result_mask & P9_STATS_BASIC) == P9_STATS_BASIC) {
1112                 inode->i_atime.tv_sec = stat->st_atime_sec;
1113                 inode->i_atime.tv_nsec = stat->st_atime_nsec;
1114                 inode->i_mtime.tv_sec = stat->st_mtime_sec;
1115                 inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
1116                 inode->i_ctime.tv_sec = stat->st_ctime_sec;
1117                 inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
1118                 inode->i_uid = stat->st_uid;
1119                 inode->i_gid = stat->st_gid;
1120                 inode->i_nlink = stat->st_nlink;
1121                 inode->i_mode = stat->st_mode;
1122                 inode->i_rdev = new_decode_dev(stat->st_rdev);
1123
1124                 if ((S_ISBLK(inode->i_mode)) || (S_ISCHR(inode->i_mode)))
1125                         init_special_inode(inode, inode->i_mode, inode->i_rdev);
1126
1127                 i_size_write(inode, stat->st_size);
1128                 inode->i_blocks = stat->st_blocks;
1129         } else {
1130                 if (stat->st_result_mask & P9_STATS_ATIME) {
1131                         inode->i_atime.tv_sec = stat->st_atime_sec;
1132                         inode->i_atime.tv_nsec = stat->st_atime_nsec;
1133                 }
1134                 if (stat->st_result_mask & P9_STATS_MTIME) {
1135                         inode->i_mtime.tv_sec = stat->st_mtime_sec;
1136                         inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
1137                 }
1138                 if (stat->st_result_mask & P9_STATS_CTIME) {
1139                         inode->i_ctime.tv_sec = stat->st_ctime_sec;
1140                         inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
1141                 }
1142                 if (stat->st_result_mask & P9_STATS_UID)
1143                         inode->i_uid = stat->st_uid;
1144                 if (stat->st_result_mask & P9_STATS_GID)
1145                         inode->i_gid = stat->st_gid;
1146                 if (stat->st_result_mask & P9_STATS_NLINK)
1147                         inode->i_nlink = stat->st_nlink;
1148                 if (stat->st_result_mask & P9_STATS_MODE) {
1149                         inode->i_mode = stat->st_mode;
1150                         if ((S_ISBLK(inode->i_mode)) ||
1151                                                 (S_ISCHR(inode->i_mode)))
1152                                 init_special_inode(inode, inode->i_mode,
1153                                                                 inode->i_rdev);
1154                 }
1155                 if (stat->st_result_mask & P9_STATS_RDEV)
1156                         inode->i_rdev = new_decode_dev(stat->st_rdev);
1157                 if (stat->st_result_mask & P9_STATS_SIZE)
1158                         i_size_write(inode, stat->st_size);
1159                 if (stat->st_result_mask & P9_STATS_BLOCKS)
1160                         inode->i_blocks = stat->st_blocks;
1161         }
1162         if (stat->st_result_mask & P9_STATS_GEN)
1163                         inode->i_generation = stat->st_gen;
1164
1165         /* Currently we don't support P9_STATS_BTIME and P9_STATS_DATA_VERSION
1166          * because the inode structure does not have fields for them.
1167          */
1168 }
1169
1170 /**
1171  * v9fs_qid2ino - convert qid into inode number
1172  * @qid: qid to hash
1173  *
1174  * BUG: potential for inode number collisions?
1175  */
1176
1177 ino_t v9fs_qid2ino(struct p9_qid *qid)
1178 {
1179         u64 path = qid->path + 2;
1180         ino_t i = 0;
1181
1182         if (sizeof(ino_t) == sizeof(path))
1183                 memcpy(&i, &path, sizeof(ino_t));
1184         else
1185                 i = (ino_t) (path ^ (path >> 32));
1186
1187         return i;
1188 }
1189
1190 /**
1191  * v9fs_readlink - read a symlink's location (internal version)
1192  * @dentry: dentry for symlink
1193  * @buffer: buffer to load symlink location into
1194  * @buflen: length of buffer
1195  *
1196  */
1197
1198 static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen)
1199 {
1200         int retval;
1201
1202         struct v9fs_session_info *v9ses;
1203         struct p9_fid *fid;
1204         struct p9_wstat *st;
1205
1206         P9_DPRINTK(P9_DEBUG_VFS, " %s\n", dentry->d_name.name);
1207         retval = -EPERM;
1208         v9ses = v9fs_inode2v9ses(dentry->d_inode);
1209         fid = v9fs_fid_lookup(dentry);
1210         if (IS_ERR(fid))
1211                 return PTR_ERR(fid);
1212
1213         if (!v9fs_proto_dotu(v9ses))
1214                 return -EBADF;
1215
1216         st = p9_client_stat(fid);
1217         if (IS_ERR(st))
1218                 return PTR_ERR(st);
1219
1220         if (!(st->mode & P9_DMSYMLINK)) {
1221                 retval = -EINVAL;
1222                 goto done;
1223         }
1224
1225         /* copy extension buffer into buffer */
1226         strncpy(buffer, st->extension, buflen);
1227
1228         P9_DPRINTK(P9_DEBUG_VFS,
1229                 "%s -> %s (%s)\n", dentry->d_name.name, st->extension, buffer);
1230
1231         retval = strnlen(buffer, buflen);
1232 done:
1233         kfree(st);
1234         return retval;
1235 }
1236
1237 /**
1238  * v9fs_vfs_follow_link - follow a symlink path
1239  * @dentry: dentry for symlink
1240  * @nd: nameidata
1241  *
1242  */
1243
1244 static void *v9fs_vfs_follow_link(struct dentry *dentry, struct nameidata *nd)
1245 {
1246         int len = 0;
1247         char *link = __getname();
1248
1249         P9_DPRINTK(P9_DEBUG_VFS, "%s n", dentry->d_name.name);
1250
1251         if (!link)
1252                 link = ERR_PTR(-ENOMEM);
1253         else {
1254                 len = v9fs_readlink(dentry, link, PATH_MAX);
1255
1256                 if (len < 0) {
1257                         __putname(link);
1258                         link = ERR_PTR(len);
1259                 } else
1260                         link[min(len, PATH_MAX-1)] = 0;
1261         }
1262         nd_set_link(nd, link);
1263
1264         return NULL;
1265 }
1266
1267 /**
1268  * v9fs_vfs_put_link - release a symlink path
1269  * @dentry: dentry for symlink
1270  * @nd: nameidata
1271  * @p: unused
1272  *
1273  */
1274
1275 static void
1276 v9fs_vfs_put_link(struct dentry *dentry, struct nameidata *nd, void *p)
1277 {
1278         char *s = nd_get_link(nd);
1279
1280         P9_DPRINTK(P9_DEBUG_VFS, " %s %s\n", dentry->d_name.name,
1281                 IS_ERR(s) ? "<error>" : s);
1282         if (!IS_ERR(s))
1283                 __putname(s);
1284 }
1285
1286 /**
1287  * v9fs_vfs_mkspecial - create a special file
1288  * @dir: inode to create special file in
1289  * @dentry: dentry to create
1290  * @mode: mode to create special file
1291  * @extension: 9p2000.u format extension string representing special file
1292  *
1293  */
1294
1295 static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry,
1296         int mode, const char *extension)
1297 {
1298         u32 perm;
1299         struct v9fs_session_info *v9ses;
1300         struct p9_fid *fid;
1301
1302         v9ses = v9fs_inode2v9ses(dir);
1303         if (!v9fs_proto_dotu(v9ses)) {
1304                 P9_DPRINTK(P9_DEBUG_ERROR, "not extended\n");
1305                 return -EPERM;
1306         }
1307
1308         perm = unixmode2p9mode(v9ses, mode);
1309         fid = v9fs_create(v9ses, dir, dentry, (char *) extension, perm,
1310                                                                 P9_OREAD);
1311         if (IS_ERR(fid))
1312                 return PTR_ERR(fid);
1313
1314         p9_client_clunk(fid);
1315         return 0;
1316 }
1317
1318 /**
1319  * v9fs_vfs_symlink - helper function to create symlinks
1320  * @dir: directory inode containing symlink
1321  * @dentry: dentry for symlink
1322  * @symname: symlink data
1323  *
1324  * See Also: 9P2000.u RFC for more information
1325  *
1326  */
1327
1328 static int
1329 v9fs_vfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
1330 {
1331         P9_DPRINTK(P9_DEBUG_VFS, " %lu,%s,%s\n", dir->i_ino,
1332                                         dentry->d_name.name, symname);
1333
1334         return v9fs_vfs_mkspecial(dir, dentry, S_IFLNK, symname);
1335 }
1336
1337 /**
1338  * v9fs_vfs_link - create a hardlink
1339  * @old_dentry: dentry for file to link to
1340  * @dir: inode destination for new link
1341  * @dentry: dentry for link
1342  *
1343  */
1344
1345 static int
1346 v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir,
1347               struct dentry *dentry)
1348 {
1349         int retval;
1350         struct p9_fid *oldfid;
1351         char *name;
1352
1353         P9_DPRINTK(P9_DEBUG_VFS,
1354                 " %lu,%s,%s\n", dir->i_ino, dentry->d_name.name,
1355                 old_dentry->d_name.name);
1356
1357         oldfid = v9fs_fid_clone(old_dentry);
1358         if (IS_ERR(oldfid))
1359                 return PTR_ERR(oldfid);
1360
1361         name = __getname();
1362         if (unlikely(!name)) {
1363                 retval = -ENOMEM;
1364                 goto clunk_fid;
1365         }
1366
1367         sprintf(name, "%d\n", oldfid->fid);
1368         retval = v9fs_vfs_mkspecial(dir, dentry, P9_DMLINK, name);
1369         __putname(name);
1370
1371 clunk_fid:
1372         p9_client_clunk(oldfid);
1373         return retval;
1374 }
1375
1376 /**
1377  * v9fs_vfs_mknod - create a special file
1378  * @dir: inode destination for new link
1379  * @dentry: dentry for file
1380  * @mode: mode for creation
1381  * @rdev: device associated with special file
1382  *
1383  */
1384
1385 static int
1386 v9fs_vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev)
1387 {
1388         int retval;
1389         char *name;
1390
1391         P9_DPRINTK(P9_DEBUG_VFS,
1392                 " %lu,%s mode: %x MAJOR: %u MINOR: %u\n", dir->i_ino,
1393                 dentry->d_name.name, mode, MAJOR(rdev), MINOR(rdev));
1394
1395         if (!new_valid_dev(rdev))
1396                 return -EINVAL;
1397
1398         name = __getname();
1399         if (!name)
1400                 return -ENOMEM;
1401         /* build extension */
1402         if (S_ISBLK(mode))
1403                 sprintf(name, "b %u %u", MAJOR(rdev), MINOR(rdev));
1404         else if (S_ISCHR(mode))
1405                 sprintf(name, "c %u %u", MAJOR(rdev), MINOR(rdev));
1406         else if (S_ISFIFO(mode))
1407                 *name = 0;
1408         else if (S_ISSOCK(mode))
1409                 *name = 0;
1410         else {
1411                 __putname(name);
1412                 return -EINVAL;
1413         }
1414
1415         retval = v9fs_vfs_mkspecial(dir, dentry, mode, name);
1416         __putname(name);
1417
1418         return retval;
1419 }
1420
1421 static const struct inode_operations v9fs_dir_inode_operations_dotu = {
1422         .create = v9fs_vfs_create,
1423         .lookup = v9fs_vfs_lookup,
1424         .symlink = v9fs_vfs_symlink,
1425         .link = v9fs_vfs_link,
1426         .unlink = v9fs_vfs_unlink,
1427         .mkdir = v9fs_vfs_mkdir,
1428         .rmdir = v9fs_vfs_rmdir,
1429         .mknod = v9fs_vfs_mknod,
1430         .rename = v9fs_vfs_rename,
1431         .getattr = v9fs_vfs_getattr,
1432         .setattr = v9fs_vfs_setattr,
1433 };
1434
1435 static const struct inode_operations v9fs_dir_inode_operations_dotl = {
1436         .create = v9fs_vfs_create,
1437         .lookup = v9fs_vfs_lookup,
1438         .symlink = v9fs_vfs_symlink,
1439         .link = v9fs_vfs_link,
1440         .unlink = v9fs_vfs_unlink,
1441         .mkdir = v9fs_vfs_mkdir,
1442         .rmdir = v9fs_vfs_rmdir,
1443         .mknod = v9fs_vfs_mknod,
1444         .rename = v9fs_vfs_rename,
1445         .getattr = v9fs_vfs_getattr_dotl,
1446         .setattr = v9fs_vfs_setattr_dotl,
1447 };
1448
1449 static const struct inode_operations v9fs_dir_inode_operations = {
1450         .create = v9fs_vfs_create,
1451         .lookup = v9fs_vfs_lookup,
1452         .unlink = v9fs_vfs_unlink,
1453         .mkdir = v9fs_vfs_mkdir,
1454         .rmdir = v9fs_vfs_rmdir,
1455         .mknod = v9fs_vfs_mknod,
1456         .rename = v9fs_vfs_rename,
1457         .getattr = v9fs_vfs_getattr,
1458         .setattr = v9fs_vfs_setattr,
1459 };
1460
1461 static const struct inode_operations v9fs_file_inode_operations = {
1462         .getattr = v9fs_vfs_getattr,
1463         .setattr = v9fs_vfs_setattr,
1464 };
1465
1466 static const struct inode_operations v9fs_file_inode_operations_dotl = {
1467         .getattr = v9fs_vfs_getattr_dotl,
1468         .setattr = v9fs_vfs_setattr_dotl,
1469 };
1470
1471 static const struct inode_operations v9fs_symlink_inode_operations = {
1472         .readlink = generic_readlink,
1473         .follow_link = v9fs_vfs_follow_link,
1474         .put_link = v9fs_vfs_put_link,
1475         .getattr = v9fs_vfs_getattr,
1476         .setattr = v9fs_vfs_setattr,
1477 };
1478
1479 static const struct inode_operations v9fs_symlink_inode_operations_dotl = {
1480         .readlink = generic_readlink,
1481         .follow_link = v9fs_vfs_follow_link,
1482         .put_link = v9fs_vfs_put_link,
1483         .getattr = v9fs_vfs_getattr_dotl,
1484         .setattr = v9fs_vfs_setattr_dotl,
1485 };