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 <linux/xattr.h>
  39 #include <linux/posix_acl.h>
  40 #include <net/9p/9p.h>
  41 #include <net/9p/client.h>
  42
  43 #include "v9fs.h"
  44 #include "v9fs_vfs.h"
  45 #include "fid.h"
  46 #include "cache.h"
  47 #include "xattr.h"
  48 #include "acl.h"
  49
  50 static const struct inode_operations v9fs_dir_inode_operations;
  51 static const struct inode_operations v9fs_dir_inode_operations_dotu;
  52 static const struct inode_operations v9fs_file_inode_operations;
  53 static const struct inode_operations v9fs_symlink_inode_operations;
  54
  55 /**
  56  * unixmode2p9mode - convert unix mode bits to plan 9
  57  * @v9ses: v9fs session information
  58  * @mode: mode to convert
  59  *
  60  */
  61
  62 static int unixmode2p9mode(struct v9fs_session_info *v9ses, int mode)
  63 {
  64         int res;
  65         res = mode & 0777;
  66         if (S_ISDIR(mode))
  67                 res |= P9_DMDIR;
  68         if (v9fs_proto_dotu(v9ses)) {
  69                 if (S_ISLNK(mode))
  70                         res |= P9_DMSYMLINK;
  71                 if (v9ses->nodev == 0) {
  72                         if (S_ISSOCK(mode))
  73                                 res |= P9_DMSOCKET;
  74                         if (S_ISFIFO(mode))
  75                                 res |= P9_DMNAMEDPIPE;
  76                         if (S_ISBLK(mode))
  77                                 res |= P9_DMDEVICE;
  78                         if (S_ISCHR(mode))
  79                                 res |= P9_DMDEVICE;
  80                 }
  81
  82                 if ((mode & S_ISUID) == S_ISUID)
  83                         res |= P9_DMSETUID;
  84                 if ((mode & S_ISGID) == S_ISGID)
  85                         res |= P9_DMSETGID;
  86                 if ((mode & S_ISVTX) == S_ISVTX)
  87                         res |= P9_DMSETVTX;
  88                 if ((mode & P9_DMLINK))
  89                         res |= P9_DMLINK;
  90         }
  91
  92         return res;
  93 }
  94
  95 /**
  96  * p9mode2unixmode- convert plan9 mode bits to unix mode bits
  97  * @v9ses: v9fs session information
  98  * @stat: p9_wstat from which mode need to be derived
  99  * @rdev: major number, minor number in case of device files.
 100  *
 101  */
 102 static int p9mode2unixmode(struct v9fs_session_info *v9ses,
 103                            struct p9_wstat *stat, dev_t *rdev)
 104 {
 105         int res;
 106         int mode = stat->mode;
 107
 108         res = mode & S_IALLUGO;
 109         *rdev = 0;
 110
 111         if ((mode & P9_DMDIR) == P9_DMDIR)
 112                 res |= S_IFDIR;
 113         else if ((mode & P9_DMSYMLINK) && (v9fs_proto_dotu(v9ses)))
 114                 res |= S_IFLNK;
 115         else if ((mode & P9_DMSOCKET) && (v9fs_proto_dotu(v9ses))
 116                  && (v9ses->nodev == 0))
 117                 res |= S_IFSOCK;
 118         else if ((mode & P9_DMNAMEDPIPE) && (v9fs_proto_dotu(v9ses))
 119                  && (v9ses->nodev == 0))
 120                 res |= S_IFIFO;
 121         else if ((mode & P9_DMDEVICE) && (v9fs_proto_dotu(v9ses))
 122                  && (v9ses->nodev == 0)) {
 123                 char type = 0, ext[32];
 124                 int major = -1, minor = -1;
 125
 126                 strncpy(ext, stat->extension, sizeof(ext));
 127                 sscanf(ext, "%c %u %u", &type, &major, &minor);
 128                 switch (type) {
 129                 case 'c':
 130                         res |= S_IFCHR;
 131                         break;
 132                 case 'b':
 133                         res |= S_IFBLK;
 134                         break;
 135                 default:
 136                         P9_DPRINTK(P9_DEBUG_ERROR,
 137                                 "Unknown special type %c %s\n", type,
 138                                 stat->extension);
 139                 };
 140                 *rdev = MKDEV(major, minor);
 141         } else
 142                 res |= S_IFREG;
 143
 144         if (v9fs_proto_dotu(v9ses)) {
 145                 if ((mode & P9_DMSETUID) == P9_DMSETUID)
 146                         res |= S_ISUID;
 147
 148                 if ((mode & P9_DMSETGID) == P9_DMSETGID)
 149                         res |= S_ISGID;
 150
 151                 if ((mode & P9_DMSETVTX) == P9_DMSETVTX)
 152                         res |= S_ISVTX;
 153         }
 154         return res;
 155 }
 156
 157 /**
 158  * v9fs_uflags2omode- convert posix open flags to plan 9 mode bits
 159  * @uflags: flags to convert
 160  * @extended: if .u extensions are active
 161  */
 162
 163 int v9fs_uflags2omode(int uflags, int extended)
 164 {
 165         int ret;
 166
 167         ret = 0;
 168         switch (uflags&3) {
 169         default:
 170         case O_RDONLY:
 171                 ret = P9_OREAD;
 172                 break;
 173
 174         case O_WRONLY:
 175                 ret = P9_OWRITE;
 176                 break;
 177
 178         case O_RDWR:
 179                 ret = P9_ORDWR;
 180                 break;
 181         }
 182
 183         if (uflags & O_TRUNC)
 184                 ret |= P9_OTRUNC;
 185
 186         if (extended) {
 187                 if (uflags & O_EXCL)
 188                         ret |= P9_OEXCL;
 189
 190                 if (uflags & O_APPEND)
 191                         ret |= P9_OAPPEND;
 192         }
 193
 194         return ret;
 195 }
 196
 197 /**
 198  * v9fs_blank_wstat - helper function to setup a 9P stat structure
 199  * @wstat: structure to initialize
 200  *
 201  */
 202
 203 void
 204 v9fs_blank_wstat(struct p9_wstat *wstat)
 205 {
 206         wstat->type = ~0;
 207         wstat->dev = ~0;
 208         wstat->qid.type = ~0;
 209         wstat->qid.version = ~0;
 210         *((long long *)&wstat->qid.path) = ~0;
 211         wstat->mode = ~0;
 212         wstat->atime = ~0;
 213         wstat->mtime = ~0;
 214         wstat->length = ~0;
 215         wstat->name = NULL;
 216         wstat->uid = NULL;
 217         wstat->gid = NULL;
 218         wstat->muid = NULL;
 219         wstat->n_uid = ~0;
 220         wstat->n_gid = ~0;
 221         wstat->n_muid = ~0;
 222         wstat->extension = NULL;
 223 }
 224
 225 /**
 226  * v9fs_alloc_inode - helper function to allocate an inode
 227  *
 228  */
 229 struct inode *v9fs_alloc_inode(struct super_block *sb)
 230 {
 231         struct v9fs_inode *v9inode;
 232         v9inode = (struct v9fs_inode *)kmem_cache_alloc(v9fs_inode_cache,
 233                                                         GFP_KERNEL);
 234         if (!v9inode)
 235                 return NULL;
 236 #ifdef CONFIG_9P_FSCACHE
 237         v9inode->fscache = NULL;
 238         spin_lock_init(&v9inode->fscache_lock);
 239 #endif
 240         v9inode->writeback_fid = NULL;
 241         v9inode->cache_validity = 0;
 242         mutex_init(&v9inode->v_mutex);
 243         return &v9inode->vfs_inode;
 244 }
 245
 246 /**
 247  * v9fs_destroy_inode - destroy an inode
 248  *
 249  */
 250
 251 static void v9fs_i_callback(struct rcu_head *head)
 252 {
 253         struct inode *inode = container_of(head, struct inode, i_rcu);
 254         INIT_LIST_HEAD(&inode->i_dentry);
 255         kmem_cache_free(v9fs_inode_cache, V9FS_I(inode));
 256 }
 257
 258 void v9fs_destroy_inode(struct inode *inode)
 259 {
 260         call_rcu(&inode->i_rcu, v9fs_i_callback);
 261 }
 262
 263 int v9fs_init_inode(struct v9fs_session_info *v9ses,
 264                     struct inode *inode, int mode, dev_t rdev)
 265 {
 266         int err = 0;
 267
 268         inode_init_owner(inode, NULL, mode);
 269         inode->i_blocks = 0;
 270         inode->i_rdev = rdev;
 271         inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
 272         inode->i_mapping->a_ops = &v9fs_addr_operations;
 273
 274         switch (mode & S_IFMT) {
 275         case S_IFIFO:
 276         case S_IFBLK:
 277         case S_IFCHR:
 278         case S_IFSOCK:
 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 if (v9fs_proto_dotu(v9ses)) {
 283                         inode->i_op = &v9fs_file_inode_operations;
 284                         inode->i_fop = &v9fs_file_operations;
 285                 } else {
 286                         P9_DPRINTK(P9_DEBUG_ERROR,
 287                                    "special files without extended mode\n");
 288                         err = -EINVAL;
 289                         goto error;
 290                 }
 291                 init_special_inode(inode, inode->i_mode, inode->i_rdev);
 292                 break;
 293         case S_IFREG:
 294                 if (v9fs_proto_dotl(v9ses)) {
 295                         inode->i_op = &v9fs_file_inode_operations_dotl;
 296                         if (v9ses->cache)
 297                                 inode->i_fop =
 298                                         &v9fs_cached_file_operations_dotl;
 299                         else
 300                                 inode->i_fop = &v9fs_file_operations_dotl;
 301                 } else {
 302                         inode->i_op = &v9fs_file_inode_operations;
 303                         if (v9ses->cache)
 304                                 inode->i_fop = &v9fs_cached_file_operations;
 305                         else
 306                                 inode->i_fop = &v9fs_file_operations;
 307                 }
 308
 309                 break;
 310         case S_IFLNK:
 311                 if (!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses)) {
 312                         P9_DPRINTK(P9_DEBUG_ERROR, "extended modes used with "
 313                                                 "legacy protocol.\n");
 314                         err = -EINVAL;
 315                         goto error;
 316                 }
 317
 318                 if (v9fs_proto_dotl(v9ses))
 319                         inode->i_op = &v9fs_symlink_inode_operations_dotl;
 320                 else
 321                         inode->i_op = &v9fs_symlink_inode_operations;
 322
 323                 break;
 324         case S_IFDIR:
 325                 inc_nlink(inode);
 326                 if (v9fs_proto_dotl(v9ses))
 327                         inode->i_op = &v9fs_dir_inode_operations_dotl;
 328                 else if (v9fs_proto_dotu(v9ses))
 329                         inode->i_op = &v9fs_dir_inode_operations_dotu;
 330                 else
 331                         inode->i_op = &v9fs_dir_inode_operations;
 332
 333                 if (v9fs_proto_dotl(v9ses))
 334                         inode->i_fop = &v9fs_dir_operations_dotl;
 335                 else
 336                         inode->i_fop = &v9fs_dir_operations;
 337
 338                 break;
 339         default:
 340                 P9_DPRINTK(P9_DEBUG_ERROR, "BAD mode 0x%x S_IFMT 0x%x\n",
 341                            mode, mode & S_IFMT);
 342                 err = -EINVAL;
 343                 goto error;
 344         }
 345 error:
 346         return err;
 347
 348 }
 349
 350 /**
 351  * v9fs_get_inode - helper function to setup an inode
 352  * @sb: superblock
 353  * @mode: mode to setup inode with
 354  *
 355  */
 356
 357 struct inode *v9fs_get_inode(struct super_block *sb, int mode, dev_t rdev)
 358 {
 359         int err;
 360         struct inode *inode;
 361         struct v9fs_session_info *v9ses = sb->s_fs_info;
 362
 363         P9_DPRINTK(P9_DEBUG_VFS, "super block: %p mode: %o\n", sb, mode);
 364
 365         inode = new_inode(sb);
 366         if (!inode) {
 367                 P9_EPRINTK(KERN_WARNING, "Problem allocating inode\n");
 368                 return ERR_PTR(-ENOMEM);
 369         }
 370         err = v9fs_init_inode(v9ses, inode, mode, rdev);
 371         if (err) {
 372                 iput(inode);
 373                 return ERR_PTR(err);
 374         }
 375         return inode;
 376 }
 377
 378 /*
 379 static struct v9fs_fid*
 380 v9fs_clone_walk(struct v9fs_session_info *v9ses, u32 fid, struct dentry *dentry)
 381 {
 382         int err;
 383         int nfid;
 384         struct v9fs_fid *ret;
 385         struct v9fs_fcall *fcall;
 386
 387         nfid = v9fs_get_idpool(&v9ses->fidpool);
 388         if (nfid < 0) {
 389                 eprintk(KERN_WARNING, "no free fids available\n");
 390                 return ERR_PTR(-ENOSPC);
 391         }
 392
 393         err = v9fs_t_walk(v9ses, fid, nfid, (char *) dentry->d_name.name,
 394                 &fcall);
 395
 396         if (err < 0) {
 397                 if (fcall && fcall->id == RWALK)
 398                         goto clunk_fid;
 399
 400                 PRINT_FCALL_ERROR("walk error", fcall);
 401                 v9fs_put_idpool(nfid, &v9ses->fidpool);
 402                 goto error;
 403         }
 404
 405         kfree(fcall);
 406         fcall = NULL;
 407         ret = v9fs_fid_create(v9ses, nfid);
 408         if (!ret) {
 409                 err = -ENOMEM;
 410                 goto clunk_fid;
 411         }
 412
 413         err = v9fs_fid_insert(ret, dentry);
 414         if (err < 0) {
 415                 v9fs_fid_destroy(ret);
 416                 goto clunk_fid;
 417         }
 418
 419         return ret;
 420
 421 clunk_fid:
 422         v9fs_t_clunk(v9ses, nfid);
 423
 424 error:
 425         kfree(fcall);
 426         return ERR_PTR(err);
 427 }
 428 */
 429
 430
 431 /**
 432  * v9fs_clear_inode - release an inode
 433  * @inode: inode to release
 434  *
 435  */
 436 void v9fs_evict_inode(struct inode *inode)
 437 {
 438         struct v9fs_inode *v9inode = V9FS_I(inode);
 439
 440         truncate_inode_pages(inode->i_mapping, 0);
 441         end_writeback(inode);
 442         filemap_fdatawrite(inode->i_mapping);
 443
 444 #ifdef CONFIG_9P_FSCACHE
 445         v9fs_cache_inode_put_cookie(inode);
 446 #endif
 447         /* clunk the fid stashed in writeback_fid */
 448         if (v9inode->writeback_fid) {
 449                 p9_client_clunk(v9inode->writeback_fid);
 450                 v9inode->writeback_fid = NULL;
 451         }
 452 }
 453
 454 static int v9fs_test_inode(struct inode *inode, void *data)
 455 {
 456         int umode;
 457         dev_t rdev;
 458         struct v9fs_inode *v9inode = V9FS_I(inode);
 459         struct p9_wstat *st = (struct p9_wstat *)data;
 460         struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);
 461
 462         umode = p9mode2unixmode(v9ses, st, &rdev);
 463         /* don't match inode of different type */
 464         if ((inode->i_mode & S_IFMT) != (umode & S_IFMT))
 465                 return 0;
 466
 467         /* compare qid details */
 468         if (memcmp(&v9inode->qid.version,
 469                    &st->qid.version, sizeof(v9inode->qid.version)))
 470                 return 0;
 471
 472         if (v9inode->qid.type != st->qid.type)
 473                 return 0;
 474         return 1;
 475 }
 476
 477 static int v9fs_test_new_inode(struct inode *inode, void *data)
 478 {
 479         return 0;
 480 }
 481
 482 static int v9fs_set_inode(struct inode *inode,  void *data)
 483 {
 484         struct v9fs_inode *v9inode = V9FS_I(inode);
 485         struct p9_wstat *st = (struct p9_wstat *)data;
 486
 487         memcpy(&v9inode->qid, &st->qid, sizeof(st->qid));
 488         return 0;
 489 }
 490
 491 static struct inode *v9fs_qid_iget(struct super_block *sb,
 492                                    struct p9_qid *qid,
 493                                    struct p9_wstat *st,
 494                                    int new)
 495 {
 496         dev_t rdev;
 497         int retval, umode;
 498         unsigned long i_ino;
 499         struct inode *inode;
 500         struct v9fs_session_info *v9ses = sb->s_fs_info;
 501         int (*test)(struct inode *, void *);
 502
 503         if (new)
 504                 test = v9fs_test_new_inode;
 505         else
 506                 test = v9fs_test_inode;
 507
 508         i_ino = v9fs_qid2ino(qid);
 509         inode = iget5_locked(sb, i_ino, test, v9fs_set_inode, st);
 510         if (!inode)
 511                 return ERR_PTR(-ENOMEM);
 512         if (!(inode->i_state & I_NEW))
 513                 return inode;
 514         /*
 515          * initialize the inode with the stat info
 516          * FIXME!! we may need support for stale inodes
 517          * later.
 518          */
 519         inode->i_ino = i_ino;
 520         umode = p9mode2unixmode(v9ses, st, &rdev);
 521         retval = v9fs_init_inode(v9ses, inode, umode, rdev);
 522         if (retval)
 523                 goto error;
 524
 525         v9fs_stat2inode(st, inode, sb);
 526 #ifdef CONFIG_9P_FSCACHE
 527         v9fs_cache_inode_get_cookie(inode);
 528 #endif
 529         unlock_new_inode(inode);
 530         return inode;
 531 error:
 532         unlock_new_inode(inode);
 533         iput(inode);
 534         return ERR_PTR(retval);
 535
 536 }
 537
 538 struct inode *
 539 v9fs_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
 540                     struct super_block *sb, int new)
 541 {
 542         struct p9_wstat *st;
 543         struct inode *inode = NULL;
 544
 545         st = p9_client_stat(fid);
 546         if (IS_ERR(st))
 547                 return ERR_CAST(st);
 548
 549         inode = v9fs_qid_iget(sb, &st->qid, st, new);
 550         p9stat_free(st);
 551         kfree(st);
 552         return inode;
 553 }
 554
 555 /**
 556  * v9fs_remove - helper function to remove files and directories
 557  * @dir: directory inode that is being deleted
 558  * @file:  dentry that is being deleted
 559  * @rmdir: removing a directory
 560  *
 561  */
 562
 563 static int v9fs_remove(struct inode *dir, struct dentry *file, int rmdir)
 564 {
 565         int retval;
 566         struct p9_fid *v9fid;
 567         struct inode *file_inode;
 568
 569         P9_DPRINTK(P9_DEBUG_VFS, "inode: %p dentry: %p rmdir: %d\n", dir, file,
 570                 rmdir);
 571
 572         file_inode = file->d_inode;
 573         v9fid = v9fs_fid_clone(file);
 574         if (IS_ERR(v9fid))
 575                 return PTR_ERR(v9fid);
 576
 577         retval = p9_client_remove(v9fid);
 578         if (!retval) {
 579                 /*
 580                  * directories on unlink should have zero
 581                  * link count
 582                  */
 583                 if (rmdir) {
 584                         clear_nlink(file_inode);
 585                         drop_nlink(dir);
 586                 } else
 587                         drop_nlink(file_inode);
 588
 589                 v9fs_invalidate_inode_attr(file_inode);
 590                 v9fs_invalidate_inode_attr(dir);
 591         }
 592         return retval;
 593 }
 594
 595 /**
 596  * v9fs_create - Create a file
 597  * @v9ses: session information
 598  * @dir: directory that dentry is being created in
 599  * @dentry:  dentry that is being created
 600  * @extension: 9p2000.u extension string to support devices, etc.
 601  * @perm: create permissions
 602  * @mode: open mode
 603  *
 604  */
 605 static struct p9_fid *
 606 v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
 607                 struct dentry *dentry, char *extension, u32 perm, u8 mode)
 608 {
 609         int err;
 610         char *name;
 611         struct p9_fid *dfid, *ofid, *fid;
 612         struct inode *inode;
 613
 614         P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name);
 615
 616         err = 0;
 617         ofid = NULL;
 618         fid = NULL;
 619         name = (char *) dentry->d_name.name;
 620         dfid = v9fs_fid_lookup(dentry->d_parent);
 621         if (IS_ERR(dfid)) {
 622                 err = PTR_ERR(dfid);
 623                 P9_DPRINTK(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
 624                 return ERR_PTR(err);
 625         }
 626
 627         /* clone a fid to use for creation */
 628         ofid = p9_client_walk(dfid, 0, NULL, 1);
 629         if (IS_ERR(ofid)) {
 630                 err = PTR_ERR(ofid);
 631                 P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
 632                 return ERR_PTR(err);
 633         }
 634
 635         err = p9_client_fcreate(ofid, name, perm, mode, extension);
 636         if (err < 0) {
 637                 P9_DPRINTK(P9_DEBUG_VFS, "p9_client_fcreate failed %d\n", err);
 638                 goto error;
 639         }
 640
 641         /* now walk from the parent so we can get unopened fid */
 642         fid = p9_client_walk(dfid, 1, &name, 1);
 643         if (IS_ERR(fid)) {
 644                 err = PTR_ERR(fid);
 645                 P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
 646                 fid = NULL;
 647                 goto error;
 648         }
 649
 650         /* instantiate inode and assign the unopened fid to the dentry */
 651         inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
 652         if (IS_ERR(inode)) {
 653                 err = PTR_ERR(inode);
 654                 P9_DPRINTK(P9_DEBUG_VFS, "inode creation failed %d\n", err);
 655                 goto error;
 656         }
 657         err = v9fs_fid_add(dentry, fid);
 658         if (err < 0)
 659                 goto error;
 660         d_instantiate(dentry, inode);
 661         return ofid;
 662 error:
 663         if (ofid)
 664                 p9_client_clunk(ofid);
 665
 666         if (fid)
 667                 p9_client_clunk(fid);
 668
 669         return ERR_PTR(err);
 670 }
 671
 672 /**
 673  * v9fs_vfs_create - VFS hook to create files
 674  * @dir: directory inode that is being created
 675  * @dentry:  dentry that is being deleted
 676  * @mode: create permissions
 677  * @nd: path information
 678  *
 679  */
 680
 681 static int
 682 v9fs_vfs_create(struct inode *dir, struct dentry *dentry, int mode,
 683                 struct nameidata *nd)
 684 {
 685         int err;
 686         u32 perm;
 687         int flags;
 688         struct file *filp;
 689         struct v9fs_inode *v9inode;
 690         struct v9fs_session_info *v9ses;
 691         struct p9_fid *fid, *inode_fid;
 692
 693         err = 0;
 694         fid = NULL;
 695         v9ses = v9fs_inode2v9ses(dir);
 696         perm = unixmode2p9mode(v9ses, mode);
 697         if (nd && nd->flags & LOOKUP_OPEN)
 698                 flags = nd->intent.open.flags - 1;
 699         else
 700                 flags = O_RDWR;
 701
 702         fid = v9fs_create(v9ses, dir, dentry, NULL, perm,
 703                                 v9fs_uflags2omode(flags,
 704                                                 v9fs_proto_dotu(v9ses)));
 705         if (IS_ERR(fid)) {
 706                 err = PTR_ERR(fid);
 707                 fid = NULL;
 708                 goto error;
 709         }
 710
 711         v9fs_invalidate_inode_attr(dir);
 712         /* if we are opening a file, assign the open fid to the file */
 713         if (nd && nd->flags & LOOKUP_OPEN) {
 714                 v9inode = V9FS_I(dentry->d_inode);
 715                 mutex_lock(&v9inode->v_mutex);
 716                 if (v9ses->cache && !v9inode->writeback_fid &&
 717                     ((flags & O_ACCMODE) != O_RDONLY)) {
 718                         /*
 719                          * clone a fid and add it to writeback_fid
 720                          * we do it during open time instead of
 721                          * page dirty time via write_begin/page_mkwrite
 722                          * because we want write after unlink usecase
 723                          * to work.
 724                          */
 725                         inode_fid = v9fs_writeback_fid(dentry);
 726                         if (IS_ERR(inode_fid)) {
 727                                 err = PTR_ERR(inode_fid);
 728                                 mutex_unlock(&v9inode->v_mutex);
 729                                 goto error;
 730                         }
 731                         v9inode->writeback_fid = (void *) inode_fid;
 732                 }
 733                 mutex_unlock(&v9inode->v_mutex);
 734                 filp = lookup_instantiate_filp(nd, dentry, generic_file_open);
 735                 if (IS_ERR(filp)) {
 736                         err = PTR_ERR(filp);
 737                         goto error;
 738                 }
 739
 740                 filp->private_data = fid;
 741 #ifdef CONFIG_9P_FSCACHE
 742                 if (v9ses->cache)
 743                         v9fs_cache_inode_set_cookie(dentry->d_inode, filp);
 744 #endif
 745         } else
 746                 p9_client_clunk(fid);
 747
 748         return 0;
 749
 750 error:
 751         if (fid)
 752                 p9_client_clunk(fid);
 753
 754         return err;
 755 }
 756
 757 /**
 758  * v9fs_vfs_mkdir - VFS mkdir hook to create a directory
 759  * @dir:  inode that is being unlinked
 760  * @dentry: dentry that is being unlinked
 761  * @mode: mode for new directory
 762  *
 763  */
 764
 765 static int v9fs_vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 766 {
 767         int err;
 768         u32 perm;
 769         struct p9_fid *fid;
 770         struct v9fs_session_info *v9ses;
 771
 772         P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name);
 773         err = 0;
 774         v9ses = v9fs_inode2v9ses(dir);
 775         perm = unixmode2p9mode(v9ses, mode | S_IFDIR);
 776         fid = v9fs_create(v9ses, dir, dentry, NULL, perm, P9_OREAD);
 777         if (IS_ERR(fid)) {
 778                 err = PTR_ERR(fid);
 779                 fid = NULL;
 780         } else {
 781                 inc_nlink(dir);
 782                 v9fs_invalidate_inode_attr(dir);
 783         }
 784
 785         if (fid)
 786                 p9_client_clunk(fid);
 787
 788         return err;
 789 }
 790
 791 /**
 792  * v9fs_vfs_lookup - VFS lookup hook to "walk" to a new inode
 793  * @dir:  inode that is being walked from
 794  * @dentry: dentry that is being walked to?
 795  * @nameidata: path data
 796  *
 797  */
 798
 799 struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
 800                                       struct nameidata *nameidata)
 801 {
 802         struct dentry *res;
 803         struct super_block *sb;
 804         struct v9fs_session_info *v9ses;
 805         struct p9_fid *dfid, *fid;
 806         struct inode *inode;
 807         char *name;
 808         int result = 0;
 809
 810         P9_DPRINTK(P9_DEBUG_VFS, "dir: %p dentry: (%s) %p nameidata: %p\n",
 811                 dir, dentry->d_name.name, dentry, nameidata);
 812
 813         if (dentry->d_name.len > NAME_MAX)
 814                 return ERR_PTR(-ENAMETOOLONG);
 815
 816         sb = dir->i_sb;
 817         v9ses = v9fs_inode2v9ses(dir);
 818         /* We can walk d_parent because we hold the dir->i_mutex */
 819         dfid = v9fs_fid_lookup(dentry->d_parent);
 820         if (IS_ERR(dfid))
 821                 return ERR_CAST(dfid);
 822
 823         name = (char *) dentry->d_name.name;
 824         fid = p9_client_walk(dfid, 1, &name, 1);
 825         if (IS_ERR(fid)) {
 826                 result = PTR_ERR(fid);
 827                 if (result == -ENOENT) {
 828                         inode = NULL;
 829                         goto inst_out;
 830                 }
 831
 832                 return ERR_PTR(result);
 833         }
 834         /*
 835          * Make sure we don't use a wrong inode due to parallel
 836          * unlink. For cached mode create calls request for new
 837          * inode. But with cache disabled, lookup should do this.
 838          */
 839         if (v9ses->cache)
 840                 inode = v9fs_get_inode_from_fid(v9ses, fid, dir->i_sb);
 841         else
 842                 inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
 843         if (IS_ERR(inode)) {
 844                 result = PTR_ERR(inode);
 845                 inode = NULL;
 846                 goto error;
 847         }
 848         result = v9fs_fid_add(dentry, fid);
 849         if (result < 0)
 850                 goto error_iput;
 851 inst_out:
 852         /*
 853          * If we had a rename on the server and a parallel lookup
 854          * for the new name, then make sure we instantiate with
 855          * the new name. ie look up for a/b, while on server somebody
 856          * moved b under k and client parallely did a lookup for
 857          * k/b.
 858          */
 859         res = d_materialise_unique(dentry, inode);
 860         if (!IS_ERR(res))
 861                 return res;
 862         result = PTR_ERR(res);
 863 error_iput:
 864         iput(inode);
 865 error:
 866         p9_client_clunk(fid);
 867
 868         return ERR_PTR(result);
 869 }
 870
 871 /**
 872  * v9fs_vfs_unlink - VFS unlink hook to delete an inode
 873  * @i:  inode that is being unlinked
 874  * @d: dentry that is being unlinked
 875  *
 876  */
 877
 878 int v9fs_vfs_unlink(struct inode *i, struct dentry *d)
 879 {
 880         return v9fs_remove(i, d, 0);
 881 }
 882
 883 /**
 884  * v9fs_vfs_rmdir - VFS unlink hook to delete a directory
 885  * @i:  inode that is being unlinked
 886  * @d: dentry that is being unlinked
 887  *
 888  */
 889
 890 int v9fs_vfs_rmdir(struct inode *i, struct dentry *d)
 891 {
 892         return v9fs_remove(i, d, 1);
 893 }
 894
 895 /**
 896  * v9fs_vfs_rename - VFS hook to rename an inode
 897  * @old_dir:  old dir inode
 898  * @old_dentry: old dentry
 899  * @new_dir: new dir inode
 900  * @new_dentry: new dentry
 901  *
 902  */
 903
 904 int
 905 v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 906                 struct inode *new_dir, struct dentry *new_dentry)
 907 {
 908         int retval;
 909         struct inode *old_inode;
 910         struct inode *new_inode;
 911         struct v9fs_session_info *v9ses;
 912         struct p9_fid *oldfid;
 913         struct p9_fid *olddirfid;
 914         struct p9_fid *newdirfid;
 915         struct p9_wstat wstat;
 916
 917         P9_DPRINTK(P9_DEBUG_VFS, "\n");
 918         retval = 0;
 919         old_inode = old_dentry->d_inode;
 920         new_inode = new_dentry->d_inode;
 921         v9ses = v9fs_inode2v9ses(old_inode);
 922         oldfid = v9fs_fid_lookup(old_dentry);
 923         if (IS_ERR(oldfid))
 924                 return PTR_ERR(oldfid);
 925
 926         olddirfid = v9fs_fid_clone(old_dentry->d_parent);
 927         if (IS_ERR(olddirfid)) {
 928                 retval = PTR_ERR(olddirfid);
 929                 goto done;
 930         }
 931
 932         newdirfid = v9fs_fid_clone(new_dentry->d_parent);
 933         if (IS_ERR(newdirfid)) {
 934                 retval = PTR_ERR(newdirfid);
 935                 goto clunk_olddir;
 936         }
 937
 938         down_write(&v9ses->rename_sem);
 939         if (v9fs_proto_dotl(v9ses)) {
 940                 retval = p9_client_rename(oldfid, newdirfid,
 941                                         (char *) new_dentry->d_name.name);
 942                 if (retval != -ENOSYS)
 943                         goto clunk_newdir;
 944         }
 945         if (old_dentry->d_parent != new_dentry->d_parent) {
 946                 /*
 947                  * 9P .u can only handle file rename in the same directory
 948                  */
 949
 950                 P9_DPRINTK(P9_DEBUG_ERROR,
 951                                 "old dir and new dir are different\n");
 952                 retval = -EXDEV;
 953                 goto clunk_newdir;
 954         }
 955         v9fs_blank_wstat(&wstat);
 956         wstat.muid = v9ses->uname;
 957         wstat.name = (char *) new_dentry->d_name.name;
 958         retval = p9_client_wstat(oldfid, &wstat);
 959
 960 clunk_newdir:
 961         if (!retval) {
 962                 if (new_inode) {
 963                         if (S_ISDIR(new_inode->i_mode))
 964                                 clear_nlink(new_inode);
 965                         else
 966                                 drop_nlink(new_inode);
 967                         /*
 968                          * Work around vfs rename rehash bug with
 969                          * FS_RENAME_DOES_D_MOVE
 970                          */
 971                         v9fs_invalidate_inode_attr(new_inode);
 972                 }
 973                 if (S_ISDIR(old_inode->i_mode)) {
 974                         if (!new_inode)
 975                                 inc_nlink(new_dir);
 976                         drop_nlink(old_dir);
 977                 }
 978                 v9fs_invalidate_inode_attr(old_inode);
 979                 v9fs_invalidate_inode_attr(old_dir);
 980                 v9fs_invalidate_inode_attr(new_dir);
 981
 982                 /* successful rename */
 983                 d_move(old_dentry, new_dentry);
 984         }
 985         up_write(&v9ses->rename_sem);
 986         p9_client_clunk(newdirfid);
 987
 988 clunk_olddir:
 989         p9_client_clunk(olddirfid);
 990
 991 done:
 992         return retval;
 993 }
 994
 995 /**
 996  * v9fs_vfs_getattr - retrieve file metadata
 997  * @mnt: mount information
 998  * @dentry: file to get attributes on
 999  * @stat: metadata structure to populate
1000  *
1001  */
1002
1003 static int
1004 v9fs_vfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
1005                  struct kstat *stat)
1006 {
1007         int err;
1008         struct v9fs_session_info *v9ses;
1009         struct p9_fid *fid;
1010         struct p9_wstat *st;
1011
1012         P9_DPRINTK(P9_DEBUG_VFS, "dentry: %p\n", dentry);
1013         err = -EPERM;
1014         v9ses = v9fs_dentry2v9ses(dentry);
1015         if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
1016                 generic_fillattr(dentry->d_inode, stat);
1017                 return 0;
1018         }
1019         fid = v9fs_fid_lookup(dentry);
1020         if (IS_ERR(fid))
1021                 return PTR_ERR(fid);
1022
1023         st = p9_client_stat(fid);
1024         if (IS_ERR(st))
1025                 return PTR_ERR(st);
1026
1027         v9fs_stat2inode(st, dentry->d_inode, dentry->d_inode->i_sb);
1028         generic_fillattr(dentry->d_inode, stat);
1029
1030         p9stat_free(st);
1031         kfree(st);
1032         return 0;
1033 }
1034
1035 /**
1036  * v9fs_vfs_setattr - set file metadata
1037  * @dentry: file whose metadata to set
1038  * @iattr: metadata assignment structure
1039  *
1040  */
1041
1042 static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
1043 {
1044         int retval;
1045         struct v9fs_session_info *v9ses;
1046         struct p9_fid *fid;
1047         struct p9_wstat wstat;
1048
1049         P9_DPRINTK(P9_DEBUG_VFS, "\n");
1050         retval = inode_change_ok(dentry->d_inode, iattr);
1051         if (retval)
1052                 return retval;
1053
1054         retval = -EPERM;
1055         v9ses = v9fs_dentry2v9ses(dentry);
1056         fid = v9fs_fid_lookup(dentry);
1057         if(IS_ERR(fid))
1058                 return PTR_ERR(fid);
1059
1060         v9fs_blank_wstat(&wstat);
1061         if (iattr->ia_valid & ATTR_MODE)
1062                 wstat.mode = unixmode2p9mode(v9ses, iattr->ia_mode);
1063
1064         if (iattr->ia_valid & ATTR_MTIME)
1065                 wstat.mtime = iattr->ia_mtime.tv_sec;
1066
1067         if (iattr->ia_valid & ATTR_ATIME)
1068                 wstat.atime = iattr->ia_atime.tv_sec;
1069
1070         if (iattr->ia_valid & ATTR_SIZE)
1071                 wstat.length = iattr->ia_size;
1072
1073         if (v9fs_proto_dotu(v9ses)) {
1074                 if (iattr->ia_valid & ATTR_UID)
1075                         wstat.n_uid = iattr->ia_uid;
1076
1077                 if (iattr->ia_valid & ATTR_GID)
1078                         wstat.n_gid = iattr->ia_gid;
1079         }
1080
1081         /* Write all dirty data */
1082         if (S_ISREG(dentry->d_inode->i_mode))
1083                 filemap_write_and_wait(dentry->d_inode->i_mapping);
1084
1085         retval = p9_client_wstat(fid, &wstat);
1086         if (retval < 0)
1087                 return retval;
1088
1089         if ((iattr->ia_valid & ATTR_SIZE) &&
1090             iattr->ia_size != i_size_read(dentry->d_inode))
1091                 truncate_setsize(dentry->d_inode, iattr->ia_size);
1092
1093         v9fs_invalidate_inode_attr(dentry->d_inode);
1094
1095         setattr_copy(dentry->d_inode, iattr);
1096         mark_inode_dirty(dentry->d_inode);
1097         return 0;
1098 }
1099
1100 /**
1101  * v9fs_stat2inode - populate an inode structure with mistat info
1102  * @stat: Plan 9 metadata (mistat) structure
1103  * @inode: inode to populate
1104  * @sb: superblock of filesystem
1105  *
1106  */
1107
1108 void
1109 v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode,
1110         struct super_block *sb)
1111 {
1112         mode_t mode;
1113         char ext[32];
1114         char tag_name[14];
1115         unsigned int i_nlink;
1116         struct v9fs_session_info *v9ses = sb->s_fs_info;
1117         struct v9fs_inode *v9inode = V9FS_I(inode);
1118
1119         inode->i_nlink = 1;
1120
1121         inode->i_atime.tv_sec = stat->atime;
1122         inode->i_mtime.tv_sec = stat->mtime;
1123         inode->i_ctime.tv_sec = stat->mtime;
1124
1125         inode->i_uid = v9ses->dfltuid;
1126         inode->i_gid = v9ses->dfltgid;
1127
1128         if (v9fs_proto_dotu(v9ses)) {
1129                 inode->i_uid = stat->n_uid;
1130                 inode->i_gid = stat->n_gid;
1131         }
1132         if ((S_ISREG(inode->i_mode)) || (S_ISDIR(inode->i_mode))) {
1133                 if (v9fs_proto_dotu(v9ses) && (stat->extension[0] != '\0')) {
1134                         /*
1135                          * Hadlink support got added later to
1136                          * to the .u extension. So there can be
1137                          * server out there that doesn't support
1138                          * this even with .u extension. So check
1139                          * for non NULL stat->extension
1140                          */
1141                         strncpy(ext, stat->extension, sizeof(ext));
1142                         /* HARDLINKCOUNT %u */
1143                         sscanf(ext, "%13s %u", tag_name, &i_nlink);
1144                         if (!strncmp(tag_name, "HARDLINKCOUNT", 13))
1145                                 inode->i_nlink = i_nlink;
1146                 }
1147         }
1148         mode = stat->mode & S_IALLUGO;
1149         mode |= inode->i_mode & ~S_IALLUGO;
1150         inode->i_mode = mode;
1151         i_size_write(inode, stat->length);
1152
1153         /* not real number of blocks, but 512 byte ones ... */
1154         inode->i_blocks = (i_size_read(inode) + 512 - 1) >> 9;
1155         v9inode->cache_validity &= ~V9FS_INO_INVALID_ATTR;
1156 }
1157
1158 /**
1159  * v9fs_qid2ino - convert qid into inode number
1160  * @qid: qid to hash
1161  *
1162  * BUG: potential for inode number collisions?
1163  */
1164
1165 ino_t v9fs_qid2ino(struct p9_qid *qid)
1166 {
1167         u64 path = qid->path + 2;
1168         ino_t i = 0;
1169
1170         if (sizeof(ino_t) == sizeof(path))
1171                 memcpy(&i, &path, sizeof(ino_t));
1172         else
1173                 i = (ino_t) (path ^ (path >> 32));
1174
1175         return i;
1176 }
1177
1178 /**
1179  * v9fs_readlink - read a symlink's location (internal version)
1180  * @dentry: dentry for symlink
1181  * @buffer: buffer to load symlink location into
1182  * @buflen: length of buffer
1183  *
1184  */
1185
1186 static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen)
1187 {
1188         int retval;
1189
1190         struct v9fs_session_info *v9ses;
1191         struct p9_fid *fid;
1192         struct p9_wstat *st;
1193
1194         P9_DPRINTK(P9_DEBUG_VFS, " %s\n", dentry->d_name.name);
1195         retval = -EPERM;
1196         v9ses = v9fs_dentry2v9ses(dentry);
1197         fid = v9fs_fid_lookup(dentry);
1198         if (IS_ERR(fid))
1199                 return PTR_ERR(fid);
1200
1201         if (!v9fs_proto_dotu(v9ses))
1202                 return -EBADF;
1203
1204         st = p9_client_stat(fid);
1205         if (IS_ERR(st))
1206                 return PTR_ERR(st);
1207
1208         if (!(st->mode & P9_DMSYMLINK)) {
1209                 retval = -EINVAL;
1210                 goto done;
1211         }
1212
1213         /* copy extension buffer into buffer */
1214         strncpy(buffer, st->extension, buflen);
1215
1216         P9_DPRINTK(P9_DEBUG_VFS,
1217                 "%s -> %s (%s)\n", dentry->d_name.name, st->extension, buffer);
1218
1219         retval = strnlen(buffer, buflen);
1220 done:
1221         p9stat_free(st);
1222         kfree(st);
1223         return retval;
1224 }
1225
1226 /**
1227  * v9fs_vfs_follow_link - follow a symlink path
1228  * @dentry: dentry for symlink
1229  * @nd: nameidata
1230  *
1231  */
1232
1233 static void *v9fs_vfs_follow_link(struct dentry *dentry, struct nameidata *nd)
1234 {
1235         int len = 0;
1236         char *link = __getname();
1237
1238         P9_DPRINTK(P9_DEBUG_VFS, "%s n", dentry->d_name.name);
1239
1240         if (!link)
1241                 link = ERR_PTR(-ENOMEM);
1242         else {
1243                 len = v9fs_readlink(dentry, link, PATH_MAX);
1244
1245                 if (len < 0) {
1246                         __putname(link);
1247                         link = ERR_PTR(len);
1248                 } else
1249                         link[min(len, PATH_MAX-1)] = 0;
1250         }
1251         nd_set_link(nd, link);
1252
1253         return NULL;
1254 }
1255
1256 /**
1257  * v9fs_vfs_put_link - release a symlink path
1258  * @dentry: dentry for symlink
1259  * @nd: nameidata
1260  * @p: unused
1261  *
1262  */
1263
1264 void
1265 v9fs_vfs_put_link(struct dentry *dentry, struct nameidata *nd, void *p)
1266 {
1267         char *s = nd_get_link(nd);
1268
1269         P9_DPRINTK(P9_DEBUG_VFS, " %s %s\n", dentry->d_name.name,
1270                 IS_ERR(s) ? "<error>" : s);
1271         if (!IS_ERR(s))
1272                 __putname(s);
1273 }
1274
1275 /**
1276  * v9fs_vfs_mkspecial - create a special file
1277  * @dir: inode to create special file in
1278  * @dentry: dentry to create
1279  * @mode: mode to create special file
1280  * @extension: 9p2000.u format extension string representing special file
1281  *
1282  */
1283
1284 static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry,
1285         int mode, const char *extension)
1286 {
1287         u32 perm;
1288         struct p9_fid *fid;
1289         struct v9fs_session_info *v9ses;
1290
1291         v9ses = v9fs_inode2v9ses(dir);
1292         if (!v9fs_proto_dotu(v9ses)) {
1293                 P9_DPRINTK(P9_DEBUG_ERROR, "not extended\n");
1294                 return -EPERM;
1295         }
1296
1297         perm = unixmode2p9mode(v9ses, mode);
1298         fid = v9fs_create(v9ses, dir, dentry, (char *) extension, perm,
1299                                                                 P9_OREAD);
1300         if (IS_ERR(fid))
1301                 return PTR_ERR(fid);
1302
1303         v9fs_invalidate_inode_attr(dir);
1304         p9_client_clunk(fid);
1305         return 0;
1306 }
1307
1308 /**
1309  * v9fs_vfs_symlink - helper function to create symlinks
1310  * @dir: directory inode containing symlink
1311  * @dentry: dentry for symlink
1312  * @symname: symlink data
1313  *
1314  * See Also: 9P2000.u RFC for more information
1315  *
1316  */
1317
1318 static int
1319 v9fs_vfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
1320 {
1321         P9_DPRINTK(P9_DEBUG_VFS, " %lu,%s,%s\n", dir->i_ino,
1322                                         dentry->d_name.name, symname);
1323
1324         return v9fs_vfs_mkspecial(dir, dentry, S_IFLNK, symname);
1325 }
1326
1327 /**
1328  * v9fs_vfs_link - create a hardlink
1329  * @old_dentry: dentry for file to link to
1330  * @dir: inode destination for new link
1331  * @dentry: dentry for link
1332  *
1333  */
1334
1335 static int
1336 v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir,
1337               struct dentry *dentry)
1338 {
1339         int retval;
1340         char *name;
1341         struct p9_fid *oldfid;
1342
1343         P9_DPRINTK(P9_DEBUG_VFS,
1344                 " %lu,%s,%s\n", dir->i_ino, dentry->d_name.name,
1345                 old_dentry->d_name.name);
1346
1347         oldfid = v9fs_fid_clone(old_dentry);
1348         if (IS_ERR(oldfid))
1349                 return PTR_ERR(oldfid);
1350
1351         name = __getname();
1352         if (unlikely(!name)) {
1353                 retval = -ENOMEM;
1354                 goto clunk_fid;
1355         }
1356
1357         sprintf(name, "%d\n", oldfid->fid);
1358         retval = v9fs_vfs_mkspecial(dir, dentry, P9_DMLINK, name);
1359         __putname(name);
1360         if (!retval) {
1361                 v9fs_refresh_inode(oldfid, old_dentry->d_inode);
1362                 v9fs_invalidate_inode_attr(dir);
1363         }
1364 clunk_fid:
1365         p9_client_clunk(oldfid);
1366         return retval;
1367 }
1368
1369 /**
1370  * v9fs_vfs_mknod - create a special file
1371  * @dir: inode destination for new link
1372  * @dentry: dentry for file
1373  * @mode: mode for creation
1374  * @rdev: device associated with special file
1375  *
1376  */
1377
1378 static int
1379 v9fs_vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev)
1380 {
1381         int retval;
1382         char *name;
1383
1384         P9_DPRINTK(P9_DEBUG_VFS,
1385                 " %lu,%s mode: %x MAJOR: %u MINOR: %u\n", dir->i_ino,
1386                 dentry->d_name.name, mode, MAJOR(rdev), MINOR(rdev));
1387
1388         if (!new_valid_dev(rdev))
1389                 return -EINVAL;
1390
1391         name = __getname();
1392         if (!name)
1393                 return -ENOMEM;
1394         /* build extension */
1395         if (S_ISBLK(mode))
1396                 sprintf(name, "b %u %u", MAJOR(rdev), MINOR(rdev));
1397         else if (S_ISCHR(mode))
1398                 sprintf(name, "c %u %u", MAJOR(rdev), MINOR(rdev));
1399         else if (S_ISFIFO(mode))
1400                 *name = 0;
1401         else if (S_ISSOCK(mode))
1402                 *name = 0;
1403         else {
1404                 __putname(name);
1405                 return -EINVAL;
1406         }
1407
1408         retval = v9fs_vfs_mkspecial(dir, dentry, mode, name);
1409         __putname(name);
1410
1411         return retval;
1412 }
1413
1414 int v9fs_refresh_inode(struct p9_fid *fid, struct inode *inode)
1415 {
1416         int umode;
1417         dev_t rdev;
1418         loff_t i_size;
1419         struct p9_wstat *st;
1420         struct v9fs_session_info *v9ses;
1421
1422         v9ses = v9fs_inode2v9ses(inode);
1423         st = p9_client_stat(fid);
1424         if (IS_ERR(st))
1425                 return PTR_ERR(st);
1426         /*
1427          * Don't update inode if the file type is different
1428          */
1429         umode = p9mode2unixmode(v9ses, st, &rdev);
1430         if ((inode->i_mode & S_IFMT) != (umode & S_IFMT))
1431                 goto out;
1432
1433         spin_lock(&inode->i_lock);
1434         /*
1435          * We don't want to refresh inode->i_size,
1436          * because we may have cached data
1437          */
1438         i_size = inode->i_size;
1439         v9fs_stat2inode(st, inode, inode->i_sb);
1440         if (v9ses->cache)
1441                 inode->i_size = i_size;
1442         spin_unlock(&inode->i_lock);
1443 out:
1444         p9stat_free(st);
1445         kfree(st);
1446         return 0;
1447 }
1448
1449 static const struct inode_operations v9fs_dir_inode_operations_dotu = {
1450         .create = v9fs_vfs_create,
1451         .lookup = v9fs_vfs_lookup,
1452         .symlink = v9fs_vfs_symlink,
1453         .link = v9fs_vfs_link,
1454         .unlink = v9fs_vfs_unlink,
1455         .mkdir = v9fs_vfs_mkdir,
1456         .rmdir = v9fs_vfs_rmdir,
1457         .mknod = v9fs_vfs_mknod,
1458         .rename = v9fs_vfs_rename,
1459         .getattr = v9fs_vfs_getattr,
1460         .setattr = v9fs_vfs_setattr,
1461 };
1462
1463 static const struct inode_operations v9fs_dir_inode_operations = {
1464         .create = v9fs_vfs_create,
1465         .lookup = v9fs_vfs_lookup,
1466         .unlink = v9fs_vfs_unlink,
1467         .mkdir = v9fs_vfs_mkdir,
1468         .rmdir = v9fs_vfs_rmdir,
1469         .mknod = v9fs_vfs_mknod,
1470         .rename = v9fs_vfs_rename,
1471         .getattr = v9fs_vfs_getattr,
1472         .setattr = v9fs_vfs_setattr,
1473 };
1474
1475 static const struct inode_operations v9fs_file_inode_operations = {
1476         .getattr = v9fs_vfs_getattr,
1477         .setattr = v9fs_vfs_setattr,
1478 };
1479
1480 static const struct inode_operations v9fs_symlink_inode_operations = {
1481         .readlink = generic_readlink,
1482         .follow_link = v9fs_vfs_follow_link,
1483         .put_link = v9fs_vfs_put_link,
1484         .getattr = v9fs_vfs_getattr,
1485         .setattr = v9fs_vfs_setattr,
1486 };
1487