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/smp_lock.h>
  34 #include <linux/inet.h>
  35 #include <linux/namei.h>
  36 #include <linux/idr.h>
  37
  38 #include "debug.h"
  39 #include "v9fs.h"
  40 #include "9p.h"
  41 #include "v9fs_vfs.h"
  42 #include "fid.h"
  43
  44 static struct inode_operations v9fs_dir_inode_operations;
  45 static struct inode_operations v9fs_dir_inode_operations_ext;
  46 static struct inode_operations v9fs_file_inode_operations;
  47 static struct inode_operations v9fs_symlink_inode_operations;
  48
  49 /**
  50  * unixmode2p9mode - convert unix mode bits to plan 9
  51  * @v9ses: v9fs session information
  52  * @mode: mode to convert
  53  *
  54  */
  55
  56 static int unixmode2p9mode(struct v9fs_session_info *v9ses, int mode)
  57 {
  58         int res;
  59         res = mode & 0777;
  60         if (S_ISDIR(mode))
  61                 res |= V9FS_DMDIR;
  62         if (v9ses->extended) {
  63                 if (S_ISLNK(mode))
  64                         res |= V9FS_DMSYMLINK;
  65                 if (v9ses->nodev == 0) {
  66                         if (S_ISSOCK(mode))
  67                                 res |= V9FS_DMSOCKET;
  68                         if (S_ISFIFO(mode))
  69                                 res |= V9FS_DMNAMEDPIPE;
  70                         if (S_ISBLK(mode))
  71                                 res |= V9FS_DMDEVICE;
  72                         if (S_ISCHR(mode))
  73                                 res |= V9FS_DMDEVICE;
  74                 }
  75
  76                 if ((mode & S_ISUID) == S_ISUID)
  77                         res |= V9FS_DMSETUID;
  78                 if ((mode & S_ISGID) == S_ISGID)
  79                         res |= V9FS_DMSETGID;
  80                 if ((mode & V9FS_DMLINK))
  81                         res |= V9FS_DMLINK;
  82         }
  83
  84         return res;
  85 }
  86
  87 /**
  88  * p9mode2unixmode- convert plan9 mode bits to unix mode bits
  89  * @v9ses: v9fs session information
  90  * @mode: mode to convert
  91  *
  92  */
  93
  94 static int p9mode2unixmode(struct v9fs_session_info *v9ses, int mode)
  95 {
  96         int res;
  97
  98         res = mode & 0777;
  99
 100         if ((mode & V9FS_DMDIR) == V9FS_DMDIR)
 101                 res |= S_IFDIR;
 102         else if ((mode & V9FS_DMSYMLINK) && (v9ses->extended))
 103                 res |= S_IFLNK;
 104         else if ((mode & V9FS_DMSOCKET) && (v9ses->extended)
 105                  && (v9ses->nodev == 0))
 106                 res |= S_IFSOCK;
 107         else if ((mode & V9FS_DMNAMEDPIPE) && (v9ses->extended)
 108                  && (v9ses->nodev == 0))
 109                 res |= S_IFIFO;
 110         else if ((mode & V9FS_DMDEVICE) && (v9ses->extended)
 111                  && (v9ses->nodev == 0))
 112                 res |= S_IFBLK;
 113         else
 114                 res |= S_IFREG;
 115
 116         if (v9ses->extended) {
 117                 if ((mode & V9FS_DMSETUID) == V9FS_DMSETUID)
 118                         res |= S_ISUID;
 119
 120                 if ((mode & V9FS_DMSETGID) == V9FS_DMSETGID)
 121                         res |= S_ISGID;
 122         }
 123
 124         return res;
 125 }
 126
 127 int v9fs_uflags2omode(int uflags)
 128 {
 129         int ret;
 130
 131         ret = 0;
 132         switch (uflags&3) {
 133         default:
 134         case O_RDONLY:
 135                 ret = V9FS_OREAD;
 136                 break;
 137
 138         case O_WRONLY:
 139                 ret = V9FS_OWRITE;
 140                 break;
 141
 142         case O_RDWR:
 143                 ret = V9FS_ORDWR;
 144                 break;
 145         }
 146
 147         if (uflags & O_EXCL)
 148                 ret |= V9FS_OEXCL;
 149
 150         if (uflags & O_TRUNC)
 151                 ret |= V9FS_OTRUNC;
 152
 153         if (uflags & O_APPEND)
 154                 ret |= V9FS_OAPPEND;
 155
 156         return ret;
 157 }
 158
 159 /**
 160  * v9fs_blank_wstat - helper function to setup a 9P stat structure
 161  * @v9ses: 9P session info (for determining extended mode)
 162  * @wstat: structure to initialize
 163  *
 164  */
 165
 166 static void
 167 v9fs_blank_wstat(struct v9fs_wstat *wstat)
 168 {
 169         wstat->type = ~0;
 170         wstat->dev = ~0;
 171         wstat->qid.type = ~0;
 172         wstat->qid.version = ~0;
 173         *((long long *)&wstat->qid.path) = ~0;
 174         wstat->mode = ~0;
 175         wstat->atime = ~0;
 176         wstat->mtime = ~0;
 177         wstat->length = ~0;
 178         wstat->name = NULL;
 179         wstat->uid = NULL;
 180         wstat->gid = NULL;
 181         wstat->muid = NULL;
 182         wstat->n_uid = ~0;
 183         wstat->n_gid = ~0;
 184         wstat->n_muid = ~0;
 185         wstat->extension = NULL;
 186 }
 187
 188 /**
 189  * v9fs_get_inode - helper function to setup an inode
 190  * @sb: superblock
 191  * @mode: mode to setup inode with
 192  *
 193  */
 194
 195 struct inode *v9fs_get_inode(struct super_block *sb, int mode)
 196 {
 197         struct inode *inode;
 198         struct v9fs_session_info *v9ses = sb->s_fs_info;
 199
 200         dprintk(DEBUG_VFS, "super block: %p mode: %o\n", sb, mode);
 201
 202         inode = new_inode(sb);
 203         if (inode) {
 204                 inode->i_mode = mode;
 205                 inode->i_uid = current->fsuid;
 206                 inode->i_gid = current->fsgid;
 207                 inode->i_blksize = sb->s_blocksize;
 208                 inode->i_blocks = 0;
 209                 inode->i_rdev = 0;
 210                 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
 211                 inode->i_mapping->a_ops = &v9fs_addr_operations;
 212
 213                 switch (mode & S_IFMT) {
 214                 case S_IFIFO:
 215                 case S_IFBLK:
 216                 case S_IFCHR:
 217                 case S_IFSOCK:
 218                         if(!v9ses->extended) {
 219                                 dprintk(DEBUG_ERROR, "special files without extended mode\n");
 220                                 return ERR_PTR(-EINVAL);
 221                         }
 222                         init_special_inode(inode, inode->i_mode,
 223                                            inode->i_rdev);
 224                         break;
 225                 case S_IFREG:
 226                         inode->i_op = &v9fs_file_inode_operations;
 227                         inode->i_fop = &v9fs_file_operations;
 228                         break;
 229                 case S_IFLNK:
 230                         if(!v9ses->extended) {
 231                                 dprintk(DEBUG_ERROR, "extended modes used w/o 9P2000.u\n");
 232                                 return ERR_PTR(-EINVAL);
 233                         }
 234                         inode->i_op = &v9fs_symlink_inode_operations;
 235                         break;
 236                 case S_IFDIR:
 237                         inode->i_nlink++;
 238                         if(v9ses->extended)
 239                                 inode->i_op = &v9fs_dir_inode_operations_ext;
 240                         else
 241                                 inode->i_op = &v9fs_dir_inode_operations;
 242                         inode->i_fop = &v9fs_dir_operations;
 243                         break;
 244                 default:
 245                         dprintk(DEBUG_ERROR, "BAD mode 0x%x S_IFMT 0x%x\n",
 246                                 mode, mode & S_IFMT);
 247                         return ERR_PTR(-EINVAL);
 248                 }
 249         } else {
 250                 eprintk(KERN_WARNING, "Problem allocating inode\n");
 251                 return ERR_PTR(-ENOMEM);
 252         }
 253         return inode;
 254 }
 255
 256 static int
 257 v9fs_create(struct v9fs_session_info *v9ses, u32 pfid, char *name, u32 perm,
 258         u8 mode, char *extension, u32 *fidp, struct v9fs_qid *qid, u32 *iounit)
 259 {
 260         u32 fid;
 261         int err;
 262         struct v9fs_fcall *fcall;
 263
 264         fid = v9fs_get_idpool(&v9ses->fidpool);
 265         if (fid < 0) {
 266                 eprintk(KERN_WARNING, "no free fids available\n");
 267                 return -ENOSPC;
 268         }
 269
 270         err = v9fs_t_walk(v9ses, pfid, fid, NULL, &fcall);
 271         if (err < 0) {
 272                 PRINT_FCALL_ERROR("clone error", fcall);
 273                 goto put_fid;
 274         }
 275         kfree(fcall);
 276
 277         err = v9fs_t_create(v9ses, fid, name, perm, mode, extension, &fcall);
 278         if (err < 0) {
 279                 PRINT_FCALL_ERROR("create fails", fcall);
 280                 goto clunk_fid;
 281         }
 282
 283         if (iounit)
 284                 *iounit = fcall->params.rcreate.iounit;
 285
 286         if (qid)
 287                 *qid = fcall->params.rcreate.qid;
 288
 289         if (fidp)
 290                 *fidp = fid;
 291
 292         kfree(fcall);
 293         return 0;
 294
 295 clunk_fid:
 296         v9fs_t_clunk(v9ses, fid);
 297         fid = V9FS_NOFID;
 298
 299 put_fid:
 300         if (fid >= 0)
 301                 v9fs_put_idpool(fid, &v9ses->fidpool);
 302
 303         kfree(fcall);
 304         return err;
 305 }
 306
 307 static struct v9fs_fid*
 308 v9fs_clone_walk(struct v9fs_session_info *v9ses, u32 fid, struct dentry *dentry)
 309 {
 310         int err;
 311         u32 nfid;
 312         struct v9fs_fid *ret;
 313         struct v9fs_fcall *fcall;
 314
 315         nfid = v9fs_get_idpool(&v9ses->fidpool);
 316         if (nfid < 0) {
 317                 eprintk(KERN_WARNING, "no free fids available\n");
 318                 return ERR_PTR(-ENOSPC);
 319         }
 320
 321         err = v9fs_t_walk(v9ses, fid, nfid, (char *) dentry->d_name.name,
 322                 &fcall);
 323
 324         if (err < 0) {
 325                 PRINT_FCALL_ERROR("walk error", fcall);
 326                 v9fs_put_idpool(nfid, &v9ses->fidpool);
 327                 goto error;
 328         }
 329
 330         kfree(fcall);
 331         fcall = NULL;
 332         ret = v9fs_fid_create(v9ses, nfid);
 333         if (!ret) {
 334                 err = -ENOMEM;
 335                 goto clunk_fid;
 336         }
 337
 338         err = v9fs_fid_insert(ret, dentry);
 339         if (err < 0) {
 340                 v9fs_fid_destroy(ret);
 341                 goto clunk_fid;
 342         }
 343
 344         return ret;
 345
 346 clunk_fid:
 347         v9fs_t_clunk(v9ses, nfid);
 348
 349 error:
 350         kfree(fcall);
 351         return ERR_PTR(err);
 352 }
 353
 354 static struct inode *
 355 v9fs_inode_from_fid(struct v9fs_session_info *v9ses, u32 fid,
 356         struct super_block *sb)
 357 {
 358         int err, umode;
 359         struct inode *ret;
 360         struct v9fs_fcall *fcall;
 361
 362         ret = NULL;
 363         err = v9fs_t_stat(v9ses, fid, &fcall);
 364         if (err) {
 365                 PRINT_FCALL_ERROR("stat error", fcall);
 366                 goto error;
 367         }
 368
 369         umode = p9mode2unixmode(v9ses, fcall->params.rstat.stat.mode);
 370         ret = v9fs_get_inode(sb, umode);
 371         if (IS_ERR(ret)) {
 372                 err = PTR_ERR(ret);
 373                 ret = NULL;
 374                 goto error;
 375         }
 376
 377         v9fs_stat2inode(&fcall->params.rstat.stat, ret, sb);
 378         kfree(fcall);
 379         return ret;
 380
 381 error:
 382         kfree(fcall);
 383         if (ret)
 384                 iput(ret);
 385
 386         return ERR_PTR(err);
 387 }
 388
 389 /**
 390  * v9fs_remove - helper function to remove files and directories
 391  * @dir: directory inode that is being deleted
 392  * @file:  dentry that is being deleted
 393  * @rmdir: removing a directory
 394  *
 395  */
 396
 397 static int v9fs_remove(struct inode *dir, struct dentry *file, int rmdir)
 398 {
 399         struct v9fs_fcall *fcall = NULL;
 400         struct super_block *sb = NULL;
 401         struct v9fs_session_info *v9ses = NULL;
 402         struct v9fs_fid *v9fid = NULL;
 403         struct inode *file_inode = NULL;
 404         int fid = -1;
 405         int result = 0;
 406
 407         dprintk(DEBUG_VFS, "inode: %p dentry: %p rmdir: %d\n", dir, file,
 408                 rmdir);
 409
 410         file_inode = file->d_inode;
 411         sb = file_inode->i_sb;
 412         v9ses = v9fs_inode2v9ses(file_inode);
 413         v9fid = v9fs_fid_lookup(file);
 414
 415         if (!v9fid) {
 416                 dprintk(DEBUG_ERROR,
 417                         "no v9fs_fid\n");
 418                 return -EBADF;
 419         }
 420
 421         fid = v9fid->fid;
 422         if (fid < 0) {
 423                 dprintk(DEBUG_ERROR, "inode #%lu, no fid!\n",
 424                         file_inode->i_ino);
 425                 return -EBADF;
 426         }
 427
 428         result = v9fs_t_remove(v9ses, fid, &fcall);
 429         if (result < 0) {
 430                 PRINT_FCALL_ERROR("remove fails", fcall);
 431         } else {
 432                 v9fs_put_idpool(fid, &v9ses->fidpool);
 433                 v9fs_fid_destroy(v9fid);
 434         }
 435
 436         kfree(fcall);
 437         return result;
 438 }
 439
 440 static int
 441 v9fs_open_created(struct inode *inode, struct file *file)
 442 {
 443         return 0;
 444 }
 445
 446 /**
 447  * v9fs_vfs_create - VFS hook to create files
 448  * @inode: directory inode that is being deleted
 449  * @dentry:  dentry that is being deleted
 450  * @mode: create permissions
 451  * @nd: path information
 452  *
 453  */
 454
 455 static int
 456 v9fs_vfs_create(struct inode *dir, struct dentry *dentry, int mode,
 457                 struct nameidata *nd)
 458 {
 459         int err;
 460         u32 fid, perm, iounit;
 461         int flags;
 462         struct v9fs_session_info *v9ses;
 463         struct v9fs_fid *dfid, *vfid, *ffid;
 464         struct inode *inode;
 465         struct v9fs_qid qid;
 466         struct file *filp;
 467
 468         inode = NULL;
 469         vfid = NULL;
 470         v9ses = v9fs_inode2v9ses(dir);
 471         dfid = v9fs_fid_lookup(dentry->d_parent);
 472         perm = unixmode2p9mode(v9ses, mode);
 473
 474         if (nd && nd->flags & LOOKUP_OPEN)
 475                 flags = nd->intent.open.flags - 1;
 476         else
 477                 flags = O_RDWR;
 478
 479         err = v9fs_create(v9ses, dfid->fid, (char *) dentry->d_name.name,
 480                 perm, v9fs_uflags2omode(flags), NULL, &fid, &qid, &iounit);
 481
 482         if (err)
 483                 goto error;
 484
 485         vfid = v9fs_clone_walk(v9ses, dfid->fid, dentry);
 486         if (IS_ERR(vfid)) {
 487                 err = PTR_ERR(vfid);
 488                 vfid = NULL;
 489                 goto error;
 490         }
 491
 492         inode = v9fs_inode_from_fid(v9ses, vfid->fid, dir->i_sb);
 493         if (IS_ERR(inode)) {
 494                 err = PTR_ERR(inode);
 495                 inode = NULL;
 496                 goto error;
 497         }
 498
 499         dentry->d_op = &v9fs_dentry_operations;
 500         d_instantiate(dentry, inode);
 501
 502         if (nd && nd->flags & LOOKUP_OPEN) {
 503                 ffid = v9fs_fid_create(v9ses, fid);
 504                 if (!ffid)
 505                         return -ENOMEM;
 506
 507                 filp = lookup_instantiate_filp(nd, dentry, v9fs_open_created);
 508                 if (IS_ERR(filp)) {
 509                         v9fs_fid_destroy(ffid);
 510                         return PTR_ERR(filp);
 511                 }
 512
 513                 ffid->rdir_pos = 0;
 514                 ffid->rdir_fcall = NULL;
 515                 ffid->fidopen = 1;
 516                 ffid->iounit = iounit;
 517                 ffid->filp = filp;
 518                 filp->private_data = ffid;
 519         }
 520
 521         return 0;
 522
 523 error:
 524         if (vfid)
 525                 v9fs_fid_destroy(vfid);
 526
 527         if (inode)
 528                 iput(inode);
 529
 530         return err;
 531 }
 532
 533 /**
 534  * v9fs_vfs_mkdir - VFS mkdir hook to create a directory
 535  * @inode:  inode that is being unlinked
 536  * @dentry: dentry that is being unlinked
 537  * @mode: mode for new directory
 538  *
 539  */
 540
 541 static int v9fs_vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 542 {
 543         int err;
 544         u32 fid, perm;
 545         struct v9fs_session_info *v9ses;
 546         struct v9fs_fid *dfid, *vfid;
 547         struct inode *inode;
 548
 549         inode = NULL;
 550         vfid = NULL;
 551         v9ses = v9fs_inode2v9ses(dir);
 552         dfid = v9fs_fid_lookup(dentry->d_parent);
 553         perm = unixmode2p9mode(v9ses, mode | S_IFDIR);
 554
 555         err = v9fs_create(v9ses, dfid->fid, (char *) dentry->d_name.name,
 556                 perm, V9FS_OREAD, NULL, &fid, NULL, NULL);
 557
 558         if (err) {
 559                 dprintk(DEBUG_ERROR, "create error %d\n", err);
 560                 goto error;
 561         }
 562
 563         err = v9fs_t_clunk(v9ses, fid);
 564         if (err) {
 565                 dprintk(DEBUG_ERROR, "clunk error %d\n", err);
 566                 goto error;
 567         }
 568
 569         vfid = v9fs_clone_walk(v9ses, dfid->fid, dentry);
 570         if (IS_ERR(vfid)) {
 571                 err = PTR_ERR(vfid);
 572                 vfid = NULL;
 573                 goto error;
 574         }
 575
 576         inode = v9fs_inode_from_fid(v9ses, vfid->fid, dir->i_sb);
 577         if (IS_ERR(inode)) {
 578                 err = PTR_ERR(inode);
 579                 inode = NULL;
 580                 goto error;
 581         }
 582
 583         dentry->d_op = &v9fs_dentry_operations;
 584         d_instantiate(dentry, inode);
 585         return 0;
 586
 587 error:
 588         if (vfid)
 589                 v9fs_fid_destroy(vfid);
 590
 591         return err;
 592 }
 593
 594 /**
 595  * v9fs_vfs_lookup - VFS lookup hook to "walk" to a new inode
 596  * @dir:  inode that is being walked from
 597  * @dentry: dentry that is being walked to?
 598  * @nameidata: path data
 599  *
 600  */
 601
 602 static struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
 603                                       struct nameidata *nameidata)
 604 {
 605         struct super_block *sb;
 606         struct v9fs_session_info *v9ses;
 607         struct v9fs_fid *dirfid;
 608         struct v9fs_fid *fid;
 609         struct inode *inode;
 610         struct v9fs_fcall *fcall = NULL;
 611         int dirfidnum = -1;
 612         int newfid = -1;
 613         int result = 0;
 614
 615         dprintk(DEBUG_VFS, "dir: %p dentry: (%s) %p nameidata: %p\n",
 616                 dir, dentry->d_name.name, dentry, nameidata);
 617
 618         sb = dir->i_sb;
 619         v9ses = v9fs_inode2v9ses(dir);
 620         dentry->d_op = &v9fs_dentry_operations;
 621         dirfid = v9fs_fid_lookup(dentry->d_parent);
 622
 623         if (!dirfid) {
 624                 dprintk(DEBUG_ERROR, "no dirfid\n");
 625                 return ERR_PTR(-EINVAL);
 626         }
 627
 628         dirfidnum = dirfid->fid;
 629
 630         if (dirfidnum < 0) {
 631                 dprintk(DEBUG_ERROR, "no dirfid for inode %p, #%lu\n",
 632                         dir, dir->i_ino);
 633                 return ERR_PTR(-EBADF);
 634         }
 635
 636         newfid = v9fs_get_idpool(&v9ses->fidpool);
 637         if (newfid < 0) {
 638                 eprintk(KERN_WARNING, "newfid fails!\n");
 639                 return ERR_PTR(-ENOSPC);
 640         }
 641
 642         result = v9fs_t_walk(v9ses, dirfidnum, newfid,
 643                 (char *)dentry->d_name.name, NULL);
 644         if (result < 0) {
 645                 v9fs_put_idpool(newfid, &v9ses->fidpool);
 646                 if (result == -ENOENT) {
 647                         d_add(dentry, NULL);
 648                         dprintk(DEBUG_VFS,
 649                                 "Return negative dentry %p count %d\n",
 650                                 dentry, atomic_read(&dentry->d_count));
 651                         return NULL;
 652                 }
 653                 dprintk(DEBUG_ERROR, "walk error:%d\n", result);
 654                 goto FreeFcall;
 655         }
 656
 657         result = v9fs_t_stat(v9ses, newfid, &fcall);
 658         if (result < 0) {
 659                 dprintk(DEBUG_ERROR, "stat error\n");
 660                 goto FreeFcall;
 661         }
 662
 663         inode = v9fs_get_inode(sb, p9mode2unixmode(v9ses,
 664                 fcall->params.rstat.stat.mode));
 665
 666         if (IS_ERR(inode) && (PTR_ERR(inode) == -ENOSPC)) {
 667                 eprintk(KERN_WARNING, "inode alloc failes, returns %ld\n",
 668                         PTR_ERR(inode));
 669
 670                 result = -ENOSPC;
 671                 goto FreeFcall;
 672         }
 673
 674         inode->i_ino = v9fs_qid2ino(&fcall->params.rstat.stat.qid);
 675
 676         fid = v9fs_fid_create(v9ses, newfid);
 677         if (fid == NULL) {
 678                 dprintk(DEBUG_ERROR, "couldn't insert\n");
 679                 result = -ENOMEM;
 680                 goto FreeFcall;
 681         }
 682
 683         result = v9fs_fid_insert(fid, dentry);
 684         if (result < 0)
 685                 goto FreeFcall;
 686
 687         fid->qid = fcall->params.rstat.stat.qid;
 688         v9fs_stat2inode(&fcall->params.rstat.stat, inode, inode->i_sb);
 689
 690         d_add(dentry, inode);
 691         kfree(fcall);
 692
 693         return NULL;
 694
 695       FreeFcall:
 696         kfree(fcall);
 697         return ERR_PTR(result);
 698 }
 699
 700 /**
 701  * v9fs_vfs_unlink - VFS unlink hook to delete an inode
 702  * @i:  inode that is being unlinked
 703  * @d: dentry that is being unlinked
 704  *
 705  */
 706
 707 static int v9fs_vfs_unlink(struct inode *i, struct dentry *d)
 708 {
 709         return v9fs_remove(i, d, 0);
 710 }
 711
 712 /**
 713  * v9fs_vfs_rmdir - VFS unlink hook to delete a directory
 714  * @i:  inode that is being unlinked
 715  * @d: dentry that is being unlinked
 716  *
 717  */
 718
 719 static int v9fs_vfs_rmdir(struct inode *i, struct dentry *d)
 720 {
 721         return v9fs_remove(i, d, 1);
 722 }
 723
 724 /**
 725  * v9fs_vfs_rename - VFS hook to rename an inode
 726  * @old_dir:  old dir inode
 727  * @old_dentry: old dentry
 728  * @new_dir: new dir inode
 729  * @new_dentry: new dentry
 730  *
 731  */
 732
 733 static int
 734 v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 735                 struct inode *new_dir, struct dentry *new_dentry)
 736 {
 737         struct inode *old_inode = old_dentry->d_inode;
 738         struct v9fs_session_info *v9ses = v9fs_inode2v9ses(old_inode);
 739         struct v9fs_fid *oldfid = v9fs_fid_lookup(old_dentry);
 740         struct v9fs_fid *olddirfid =
 741             v9fs_fid_lookup(old_dentry->d_parent);
 742         struct v9fs_fid *newdirfid =
 743             v9fs_fid_lookup(new_dentry->d_parent);
 744         struct v9fs_wstat wstat;
 745         struct v9fs_fcall *fcall = NULL;
 746         int fid = -1;
 747         int olddirfidnum = -1;
 748         int newdirfidnum = -1;
 749         int retval = 0;
 750
 751         dprintk(DEBUG_VFS, "\n");
 752
 753         if ((!oldfid) || (!olddirfid) || (!newdirfid)) {
 754                 dprintk(DEBUG_ERROR, "problem with arguments\n");
 755                 return -EBADF;
 756         }
 757
 758         /* 9P can only handle file rename in the same directory */
 759         if (memcmp(&olddirfid->qid, &newdirfid->qid, sizeof(newdirfid->qid))) {
 760                 dprintk(DEBUG_ERROR, "old dir and new dir are different\n");
 761                 retval = -EPERM;
 762                 goto FreeFcallnBail;
 763         }
 764
 765         fid = oldfid->fid;
 766         olddirfidnum = olddirfid->fid;
 767         newdirfidnum = newdirfid->fid;
 768
 769         if (fid < 0) {
 770                 dprintk(DEBUG_ERROR, "no fid for old file #%lu\n",
 771                         old_inode->i_ino);
 772                 retval = -EBADF;
 773                 goto FreeFcallnBail;
 774         }
 775
 776         v9fs_blank_wstat(&wstat);
 777         wstat.muid = v9ses->name;
 778         wstat.name = (char *) new_dentry->d_name.name;
 779
 780         retval = v9fs_t_wstat(v9ses, fid, &wstat, &fcall);
 781
 782       FreeFcallnBail:
 783         if (retval < 0)
 784                 PRINT_FCALL_ERROR("wstat error", fcall);
 785
 786         kfree(fcall);
 787         return retval;
 788 }
 789
 790 /**
 791  * v9fs_vfs_getattr - retrieve file metadata
 792  * @mnt - mount information
 793  * @dentry - file to get attributes on
 794  * @stat - metadata structure to populate
 795  *
 796  */
 797
 798 static int
 799 v9fs_vfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
 800                  struct kstat *stat)
 801 {
 802         struct v9fs_fcall *fcall = NULL;
 803         struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dentry->d_inode);
 804         struct v9fs_fid *fid = v9fs_fid_lookup(dentry);
 805         int err = -EPERM;
 806
 807         dprintk(DEBUG_VFS, "dentry: %p\n", dentry);
 808         if (!fid) {
 809                 dprintk(DEBUG_ERROR,
 810                         "couldn't find fid associated with dentry\n");
 811                 return -EBADF;
 812         }
 813
 814         err = v9fs_t_stat(v9ses, fid->fid, &fcall);
 815
 816         if (err < 0)
 817                 dprintk(DEBUG_ERROR, "stat error\n");
 818         else {
 819                 v9fs_stat2inode(&fcall->params.rstat.stat, dentry->d_inode,
 820                                   dentry->d_inode->i_sb);
 821                 generic_fillattr(dentry->d_inode, stat);
 822         }
 823
 824         kfree(fcall);
 825         return err;
 826 }
 827
 828 /**
 829  * v9fs_vfs_setattr - set file metadata
 830  * @dentry: file whose metadata to set
 831  * @iattr: metadata assignment structure
 832  *
 833  */
 834
 835 static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
 836 {
 837         struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dentry->d_inode);
 838         struct v9fs_fid *fid = v9fs_fid_lookup(dentry);
 839         struct v9fs_fcall *fcall = NULL;
 840         struct v9fs_wstat wstat;
 841         int res = -EPERM;
 842
 843         dprintk(DEBUG_VFS, "\n");
 844
 845         if (!fid) {
 846                 dprintk(DEBUG_ERROR,
 847                         "Couldn't find fid associated with dentry\n");
 848                 return -EBADF;
 849         }
 850
 851         v9fs_blank_wstat(&wstat);
 852         if (iattr->ia_valid & ATTR_MODE)
 853                 wstat.mode = unixmode2p9mode(v9ses, iattr->ia_mode);
 854
 855         if (iattr->ia_valid & ATTR_MTIME)
 856                 wstat.mtime = iattr->ia_mtime.tv_sec;
 857
 858         if (iattr->ia_valid & ATTR_ATIME)
 859                 wstat.atime = iattr->ia_atime.tv_sec;
 860
 861         if (iattr->ia_valid & ATTR_SIZE)
 862                 wstat.length = iattr->ia_size;
 863
 864         if (v9ses->extended) {
 865                 if (iattr->ia_valid & ATTR_UID)
 866                         wstat.n_uid = iattr->ia_uid;
 867
 868                 if (iattr->ia_valid & ATTR_GID)
 869                         wstat.n_gid = iattr->ia_gid;
 870         }
 871
 872         res = v9fs_t_wstat(v9ses, fid->fid, &wstat, &fcall);
 873
 874         if (res < 0)
 875                 PRINT_FCALL_ERROR("wstat error", fcall);
 876
 877         kfree(fcall);
 878         if (res >= 0)
 879                 res = inode_setattr(dentry->d_inode, iattr);
 880
 881         return res;
 882 }
 883
 884 /**
 885  * v9fs_stat2inode - populate an inode structure with mistat info
 886  * @stat: Plan 9 metadata (mistat) structure
 887  * @inode: inode to populate
 888  * @sb: superblock of filesystem
 889  *
 890  */
 891
 892 void
 893 v9fs_stat2inode(struct v9fs_stat *stat, struct inode *inode,
 894         struct super_block *sb)
 895 {
 896         int n;
 897         char ext[32];
 898         struct v9fs_session_info *v9ses = sb->s_fs_info;
 899
 900         inode->i_nlink = 1;
 901
 902         inode->i_atime.tv_sec = stat->atime;
 903         inode->i_mtime.tv_sec = stat->mtime;
 904         inode->i_ctime.tv_sec = stat->mtime;
 905
 906         inode->i_uid = v9ses->uid;
 907         inode->i_gid = v9ses->gid;
 908
 909         if (v9ses->extended) {
 910                 inode->i_uid = stat->n_uid;
 911                 inode->i_gid = stat->n_gid;
 912         }
 913
 914         inode->i_mode = p9mode2unixmode(v9ses, stat->mode);
 915         if ((S_ISBLK(inode->i_mode)) || (S_ISCHR(inode->i_mode))) {
 916                 char type = 0;
 917                 int major = -1;
 918                 int minor = -1;
 919
 920                 n = stat->extension.len;
 921                 if (n > sizeof(ext)-1)
 922                         n = sizeof(ext)-1;
 923                 memmove(ext, stat->extension.str, n);
 924                 ext[n] = 0;
 925                 sscanf(ext, "%c %u %u", &type, &major, &minor);
 926                 switch (type) {
 927                 case 'c':
 928                         inode->i_mode &= ~S_IFBLK;
 929                         inode->i_mode |= S_IFCHR;
 930                         break;
 931                 case 'b':
 932                         break;
 933                 default:
 934                         dprintk(DEBUG_ERROR, "Unknown special type %c (%.*s)\n",
 935                                 type, stat->extension.len, stat->extension.str);
 936                 };
 937                 inode->i_rdev = MKDEV(major, minor);
 938         } else
 939                 inode->i_rdev = 0;
 940
 941         inode->i_size = stat->length;
 942
 943         inode->i_blksize = sb->s_blocksize;
 944         inode->i_blocks =
 945             (inode->i_size + inode->i_blksize - 1) >> sb->s_blocksize_bits;
 946 }
 947
 948 /**
 949  * v9fs_qid2ino - convert qid into inode number
 950  * @qid: qid to hash
 951  *
 952  * BUG: potential for inode number collisions?
 953  */
 954
 955 ino_t v9fs_qid2ino(struct v9fs_qid *qid)
 956 {
 957         u64 path = qid->path + 2;
 958         ino_t i = 0;
 959
 960         if (sizeof(ino_t) == sizeof(path))
 961                 memcpy(&i, &path, sizeof(ino_t));
 962         else
 963                 i = (ino_t) (path ^ (path >> 32));
 964
 965         return i;
 966 }
 967
 968 /**
 969  * v9fs_readlink - read a symlink's location (internal version)
 970  * @dentry: dentry for symlink
 971  * @buffer: buffer to load symlink location into
 972  * @buflen: length of buffer
 973  *
 974  */
 975
 976 static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen)
 977 {
 978         int retval = -EPERM;
 979
 980         struct v9fs_fcall *fcall = NULL;
 981         struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dentry->d_inode);
 982         struct v9fs_fid *fid = v9fs_fid_lookup(dentry);
 983
 984         if (!fid) {
 985                 dprintk(DEBUG_ERROR, "could not resolve fid from dentry\n");
 986                 retval = -EBADF;
 987                 goto FreeFcall;
 988         }
 989
 990         if (!v9ses->extended) {
 991                 retval = -EBADF;
 992                 dprintk(DEBUG_ERROR, "not extended\n");
 993                 goto FreeFcall;
 994         }
 995
 996         dprintk(DEBUG_VFS, " %s\n", dentry->d_name.name);
 997         retval = v9fs_t_stat(v9ses, fid->fid, &fcall);
 998
 999         if (retval < 0) {
1000                 dprintk(DEBUG_ERROR, "stat error\n");
1001                 goto FreeFcall;
1002         }
1003
1004         if (!fcall)
1005                 return -EIO;
1006
1007         if (!(fcall->params.rstat.stat.mode & V9FS_DMSYMLINK)) {
1008                 retval = -EINVAL;
1009                 goto FreeFcall;
1010         }
1011
1012         /* copy extension buffer into buffer */
1013         if (fcall->params.rstat.stat.extension.len < buflen)
1014                 buflen = fcall->params.rstat.stat.extension.len + 1;
1015
1016         memmove(buffer, fcall->params.rstat.stat.extension.str, buflen - 1);
1017         buffer[buflen-1] = 0;
1018
1019         dprintk(DEBUG_ERROR, "%s -> %.*s (%s)\n", dentry->d_name.name, fcall->params.rstat.stat.extension.len,
1020                 fcall->params.rstat.stat.extension.str, buffer);
1021         retval = buflen;
1022
1023       FreeFcall:
1024         kfree(fcall);
1025
1026         return retval;
1027 }
1028
1029 /**
1030  * v9fs_vfs_readlink - read a symlink's location
1031  * @dentry: dentry for symlink
1032  * @buf: buffer to load symlink location into
1033  * @buflen: length of buffer
1034  *
1035  */
1036
1037 static int v9fs_vfs_readlink(struct dentry *dentry, char __user * buffer,
1038                              int buflen)
1039 {
1040         int retval;
1041         int ret;
1042         char *link = __getname();
1043
1044         if (buflen > PATH_MAX)
1045                 buflen = PATH_MAX;
1046
1047         dprintk(DEBUG_VFS, " dentry: %s (%p)\n", dentry->d_iname, dentry);
1048
1049         retval = v9fs_readlink(dentry, link, buflen);
1050
1051         if (retval > 0) {
1052                 if ((ret = copy_to_user(buffer, link, retval)) != 0) {
1053                         dprintk(DEBUG_ERROR, "problem copying to user: %d\n",
1054                                 ret);
1055                         retval = ret;
1056                 }
1057         }
1058
1059         __putname(link);
1060         return retval;
1061 }
1062
1063 /**
1064  * v9fs_vfs_follow_link - follow a symlink path
1065  * @dentry: dentry for symlink
1066  * @nd: nameidata
1067  *
1068  */
1069
1070 static void *v9fs_vfs_follow_link(struct dentry *dentry, struct nameidata *nd)
1071 {
1072         int len = 0;
1073         char *link = __getname();
1074
1075         dprintk(DEBUG_VFS, "%s n", dentry->d_name.name);
1076
1077         if (!link)
1078                 link = ERR_PTR(-ENOMEM);
1079         else {
1080                 len = v9fs_readlink(dentry, link, PATH_MAX);
1081
1082                 if (len < 0) {
1083                         __putname(link);
1084                         link = ERR_PTR(len);
1085                 } else
1086                         link[len] = 0;
1087         }
1088         nd_set_link(nd, link);
1089
1090         return NULL;
1091 }
1092
1093 /**
1094  * v9fs_vfs_put_link - release a symlink path
1095  * @dentry: dentry for symlink
1096  * @nd: nameidata
1097  *
1098  */
1099
1100 static void v9fs_vfs_put_link(struct dentry *dentry, struct nameidata *nd, void *p)
1101 {
1102         char *s = nd_get_link(nd);
1103
1104         dprintk(DEBUG_VFS, " %s %s\n", dentry->d_name.name, s);
1105         if (!IS_ERR(s))
1106                 __putname(s);
1107 }
1108
1109 static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry,
1110         int mode, const char *extension)
1111 {
1112         int err;
1113         u32 fid, perm;
1114         struct v9fs_session_info *v9ses;
1115         struct v9fs_fid *dfid, *vfid;
1116         struct inode *inode;
1117
1118         inode = NULL;
1119         vfid = NULL;
1120         v9ses = v9fs_inode2v9ses(dir);
1121         dfid = v9fs_fid_lookup(dentry->d_parent);
1122         perm = unixmode2p9mode(v9ses, mode);
1123
1124         if (!v9ses->extended) {
1125                 dprintk(DEBUG_ERROR, "not extended\n");
1126                 return -EPERM;
1127         }
1128
1129         err = v9fs_create(v9ses, dfid->fid, (char *) dentry->d_name.name,
1130                 perm, V9FS_OREAD, (char *) extension, &fid, NULL, NULL);
1131
1132         if (err)
1133                 goto error;
1134
1135         err = v9fs_t_clunk(v9ses, fid);
1136         if (err)
1137                 goto error;
1138
1139         vfid = v9fs_clone_walk(v9ses, dfid->fid, dentry);
1140         if (IS_ERR(vfid)) {
1141                 err = PTR_ERR(vfid);
1142                 vfid = NULL;
1143                 goto error;
1144         }
1145
1146         inode = v9fs_inode_from_fid(v9ses, vfid->fid, dir->i_sb);
1147         if (IS_ERR(inode)) {
1148                 err = PTR_ERR(inode);
1149                 inode = NULL;
1150                 goto error;
1151         }
1152
1153         dentry->d_op = &v9fs_dentry_operations;
1154         d_instantiate(dentry, inode);
1155         return 0;
1156
1157 error:
1158         if (vfid)
1159                 v9fs_fid_destroy(vfid);
1160
1161         if (inode)
1162                 iput(inode);
1163
1164         return err;
1165
1166 }
1167
1168 /**
1169  * v9fs_vfs_symlink - helper function to create symlinks
1170  * @dir: directory inode containing symlink
1171  * @dentry: dentry for symlink
1172  * @symname: symlink data
1173  *
1174  * See 9P2000.u RFC for more information
1175  *
1176  */
1177
1178 static int
1179 v9fs_vfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
1180 {
1181         dprintk(DEBUG_VFS, " %lu,%s,%s\n", dir->i_ino, dentry->d_name.name,
1182                 symname);
1183
1184         return v9fs_vfs_mkspecial(dir, dentry, S_IFLNK, symname);
1185 }
1186
1187 /**
1188  * v9fs_vfs_link - create a hardlink
1189  * @old_dentry: dentry for file to link to
1190  * @dir: inode destination for new link
1191  * @dentry: dentry for link
1192  *
1193  */
1194
1195 /* XXX - lots of code dup'd from symlink and creates,
1196  * figure out a better reuse strategy
1197  */
1198
1199 static int
1200 v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir,
1201               struct dentry *dentry)
1202 {
1203         int retval;
1204         struct v9fs_fid *oldfid;
1205         char *name;
1206
1207         dprintk(DEBUG_VFS, " %lu,%s,%s\n", dir->i_ino, dentry->d_name.name,
1208                 old_dentry->d_name.name);
1209
1210         oldfid = v9fs_fid_lookup(old_dentry);
1211         if (!oldfid) {
1212                 dprintk(DEBUG_ERROR, "can't find oldfid\n");
1213                 return -EPERM;
1214         }
1215
1216         name = __getname();
1217         sprintf(name, "%d\n", oldfid->fid);
1218         retval = v9fs_vfs_mkspecial(dir, dentry, V9FS_DMLINK, name);
1219         __putname(name);
1220
1221         return retval;
1222 }
1223
1224 /**
1225  * v9fs_vfs_mknod - create a special file
1226  * @dir: inode destination for new link
1227  * @dentry: dentry for file
1228  * @mode: mode for creation
1229  * @dev_t: device associated with special file
1230  *
1231  */
1232
1233 static int
1234 v9fs_vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev)
1235 {
1236         int retval;
1237         char *name;
1238
1239         dprintk(DEBUG_VFS, " %lu,%s mode: %x MAJOR: %u MINOR: %u\n", dir->i_ino,
1240                 dentry->d_name.name, mode, MAJOR(rdev), MINOR(rdev));
1241
1242         if (!new_valid_dev(rdev))
1243                 return -EINVAL;
1244
1245         name = __getname();
1246         if (!name)
1247                 return -ENOMEM;
1248         /* build extension */
1249         if (S_ISBLK(mode))
1250                 sprintf(name, "b %u %u", MAJOR(rdev), MINOR(rdev));
1251         else if (S_ISCHR(mode))
1252                 sprintf(name, "c %u %u", MAJOR(rdev), MINOR(rdev));
1253         else if (S_ISFIFO(mode))
1254                 *name = 0;
1255         else {
1256                 __putname(name);
1257                 return -EINVAL;
1258         }
1259
1260         retval = v9fs_vfs_mkspecial(dir, dentry, mode, name);
1261         __putname(name);
1262
1263         return retval;
1264 }
1265
1266 static struct inode_operations v9fs_dir_inode_operations_ext = {
1267         .create = v9fs_vfs_create,
1268         .lookup = v9fs_vfs_lookup,
1269         .symlink = v9fs_vfs_symlink,
1270         .link = v9fs_vfs_link,
1271         .unlink = v9fs_vfs_unlink,
1272         .mkdir = v9fs_vfs_mkdir,
1273         .rmdir = v9fs_vfs_rmdir,
1274         .mknod = v9fs_vfs_mknod,
1275         .rename = v9fs_vfs_rename,
1276         .readlink = v9fs_vfs_readlink,
1277         .getattr = v9fs_vfs_getattr,
1278         .setattr = v9fs_vfs_setattr,
1279 };
1280
1281 static struct inode_operations v9fs_dir_inode_operations = {
1282         .create = v9fs_vfs_create,
1283         .lookup = v9fs_vfs_lookup,
1284         .unlink = v9fs_vfs_unlink,
1285         .mkdir = v9fs_vfs_mkdir,
1286         .rmdir = v9fs_vfs_rmdir,
1287         .mknod = v9fs_vfs_mknod,
1288         .rename = v9fs_vfs_rename,
1289         .getattr = v9fs_vfs_getattr,
1290         .setattr = v9fs_vfs_setattr,
1291 };
1292
1293 static struct inode_operations v9fs_file_inode_operations = {
1294         .getattr = v9fs_vfs_getattr,
1295         .setattr = v9fs_vfs_setattr,
1296 };
1297
1298 static struct inode_operations v9fs_symlink_inode_operations = {
1299         .readlink = v9fs_vfs_readlink,
1300         .follow_link = v9fs_vfs_follow_link,
1301         .put_link = v9fs_vfs_put_link,
1302         .getattr = v9fs_vfs_getattr,
1303         .setattr = v9fs_vfs_setattr,
1304 };