fs/gfs2/ops_inode.c

   1 /*
   2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3  * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
   4  *
   5  * This copyrighted material is made available to anyone wishing to use,
   6  * modify, copy, or redistribute it subject to the terms and conditions
   7  * of the GNU General Public License version 2.
   8  */
   9
  10 #include <linux/sched.h>
  11 #include <linux/slab.h>
  12 #include <linux/spinlock.h>
  13 #include <linux/completion.h>
  14 #include <linux/buffer_head.h>
  15 #include <linux/namei.h>
  16 #include <linux/utsname.h>
  17 #include <linux/mm.h>
  18 #include <linux/xattr.h>
  19 #include <linux/posix_acl.h>
  20 #include <linux/gfs2_ondisk.h>
  21 #include <linux/crc32.h>
  22 #include <linux/lm_interface.h>
  23 #include <asm/uaccess.h>
  24
  25 #include "gfs2.h"
  26 #include "incore.h"
  27 #include "acl.h"
  28 #include "bmap.h"
  29 #include "dir.h"
  30 #include "eaops.h"
  31 #include "eattr.h"
  32 #include "glock.h"
  33 #include "inode.h"
  34 #include "meta_io.h"
  35 #include "ops_dentry.h"
  36 #include "ops_inode.h"
  37 #include "quota.h"
  38 #include "rgrp.h"
  39 #include "trans.h"
  40 #include "util.h"
  41
  42 /**
  43  * gfs2_create - Create a file
  44  * @dir: The directory in which to create the file
  45  * @dentry: The dentry of the new file
  46  * @mode: The mode of the new file
  47  *
  48  * Returns: errno
  49  */
  50
  51 static int gfs2_create(struct inode *dir, struct dentry *dentry,
  52                        int mode, struct nameidata *nd)
  53 {
  54         struct gfs2_inode *dip = GFS2_I(dir);
  55         struct gfs2_sbd *sdp = GFS2_SB(dir);
  56         struct gfs2_holder ghs[2];
  57         struct inode *inode;
  58
  59         gfs2_holder_init(dip->i_gl, 0, 0, ghs);
  60
  61         for (;;) {
  62                 inode = gfs2_createi(ghs, &dentry->d_name, S_IFREG | mode);
  63                 if (!IS_ERR(inode)) {
  64                         gfs2_trans_end(sdp);
  65                         if (dip->i_alloc.al_rgd)
  66                                 gfs2_inplace_release(dip);
  67                         gfs2_quota_unlock(dip);
  68                         gfs2_alloc_put(dip);
  69                         gfs2_glock_dq_uninit_m(2, ghs);
  70                         mark_inode_dirty(inode);
  71                         break;
  72                 } else if (PTR_ERR(inode) != -EEXIST ||
  73                            (nd->intent.open.flags & O_EXCL)) {
  74                         gfs2_holder_uninit(ghs);
  75                         return PTR_ERR(inode);
  76                 }
  77
  78                 inode = gfs2_lookupi(dir, &dentry->d_name, 0, nd);
  79                 if (inode) {
  80                         if (!IS_ERR(inode)) {
  81                                 gfs2_holder_uninit(ghs);
  82                                 break;
  83                         } else {
  84                                 gfs2_holder_uninit(ghs);
  85                                 return PTR_ERR(inode);
  86                         }
  87                 }
  88         }
  89
  90         d_instantiate(dentry, inode);
  91
  92         return 0;
  93 }
  94
  95 /**
  96  * gfs2_lookup - Look up a filename in a directory and return its inode
  97  * @dir: The directory inode
  98  * @dentry: The dentry of the new inode
  99  * @nd: passed from Linux VFS, ignored by us
 100  *
 101  * Called by the VFS layer. Lock dir and call gfs2_lookupi()
 102  *
 103  * Returns: errno
 104  */
 105
 106 static struct dentry *gfs2_lookup(struct inode *dir, struct dentry *dentry,
 107                                   struct nameidata *nd)
 108 {
 109         struct inode *inode = NULL;
 110
 111         dentry->d_op = &gfs2_dops;
 112
 113         inode = gfs2_lookupi(dir, &dentry->d_name, 0, nd);
 114         if (inode && IS_ERR(inode))
 115                 return ERR_PTR(PTR_ERR(inode));
 116
 117         if (inode)
 118                 return d_splice_alias(inode, dentry);
 119         d_add(dentry, inode);
 120
 121         return NULL;
 122 }
 123
 124 /**
 125  * gfs2_link - Link to a file
 126  * @old_dentry: The inode to link
 127  * @dir: Add link to this directory
 128  * @dentry: The name of the link
 129  *
 130  * Link the inode in "old_dentry" into the directory "dir" with the
 131  * name in "dentry".
 132  *
 133  * Returns: errno
 134  */
 135
 136 static int gfs2_link(struct dentry *old_dentry, struct inode *dir,
 137                      struct dentry *dentry)
 138 {
 139         struct gfs2_inode *dip = GFS2_I(dir);
 140         struct gfs2_sbd *sdp = GFS2_SB(dir);
 141         struct inode *inode = old_dentry->d_inode;
 142         struct gfs2_inode *ip = GFS2_I(inode);
 143         struct gfs2_holder ghs[2];
 144         int alloc_required;
 145         int error;
 146
 147         if (S_ISDIR(ip->i_di.di_mode))
 148                 return -EPERM;
 149
 150         gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
 151         gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + 1);
 152
 153         error = gfs2_glock_nq_m(2, ghs);
 154         if (error)
 155                 goto out;
 156
 157         error = permission(dir, MAY_WRITE | MAY_EXEC, NULL);
 158         if (error)
 159                 goto out_gunlock;
 160
 161         error = gfs2_dir_search(dir, &dentry->d_name, NULL, NULL);
 162         switch (error) {
 163         case -ENOENT:
 164                 break;
 165         case 0:
 166                 error = -EEXIST;
 167         default:
 168                 goto out_gunlock;
 169         }
 170
 171         error = -EINVAL;
 172         if (!dip->i_di.di_nlink)
 173                 goto out_gunlock;
 174         error = -EFBIG;
 175         if (dip->i_di.di_entries == (u32)-1)
 176                 goto out_gunlock;
 177         error = -EPERM;
 178         if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
 179                 goto out_gunlock;
 180         error = -EINVAL;
 181         if (!ip->i_di.di_nlink)
 182                 goto out_gunlock;
 183         error = -EMLINK;
 184         if (ip->i_di.di_nlink == (u32)-1)
 185                 goto out_gunlock;
 186
 187         alloc_required = error = gfs2_diradd_alloc_required(dir, &dentry->d_name);
 188         if (error < 0)
 189                 goto out_gunlock;
 190         error = 0;
 191
 192         if (alloc_required) {
 193                 struct gfs2_alloc *al = gfs2_alloc_get(dip);
 194
 195                 error = gfs2_quota_lock(dip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
 196                 if (error)
 197                         goto out_alloc;
 198
 199                 error = gfs2_quota_check(dip, dip->i_di.di_uid,
 200                                          dip->i_di.di_gid);
 201                 if (error)
 202                         goto out_gunlock_q;
 203
 204                 al->al_requested = sdp->sd_max_dirres;
 205
 206                 error = gfs2_inplace_reserve(dip);
 207                 if (error)
 208                         goto out_gunlock_q;
 209
 210                 error = gfs2_trans_begin(sdp, sdp->sd_max_dirres +
 211                                          al->al_rgd->rd_ri.ri_length +
 212                                          2 * RES_DINODE + RES_STATFS +
 213                                          RES_QUOTA, 0);
 214                 if (error)
 215                         goto out_ipres;
 216         } else {
 217                 error = gfs2_trans_begin(sdp, 2 * RES_DINODE + RES_LEAF, 0);
 218                 if (error)
 219                         goto out_ipres;
 220         }
 221
 222         error = gfs2_dir_add(dir, &dentry->d_name, &ip->i_num,
 223                              IF2DT(ip->i_di.di_mode));
 224         if (error)
 225                 goto out_end_trans;
 226
 227         error = gfs2_change_nlink(ip, +1);
 228
 229 out_end_trans:
 230         gfs2_trans_end(sdp);
 231 out_ipres:
 232         if (alloc_required)
 233                 gfs2_inplace_release(dip);
 234 out_gunlock_q:
 235         if (alloc_required)
 236                 gfs2_quota_unlock(dip);
 237 out_alloc:
 238         if (alloc_required)
 239                 gfs2_alloc_put(dip);
 240 out_gunlock:
 241         gfs2_glock_dq_m(2, ghs);
 242 out:
 243         gfs2_holder_uninit(ghs);
 244         gfs2_holder_uninit(ghs + 1);
 245         if (!error) {
 246                 atomic_inc(&inode->i_count);
 247                 d_instantiate(dentry, inode);
 248                 mark_inode_dirty(inode);
 249         }
 250         return error;
 251 }
 252
 253 /**
 254  * gfs2_unlink - Unlink a file
 255  * @dir: The inode of the directory containing the file to unlink
 256  * @dentry: The file itself
 257  *
 258  * Unlink a file.  Call gfs2_unlinki()
 259  *
 260  * Returns: errno
 261  */
 262
 263 static int gfs2_unlink(struct inode *dir, struct dentry *dentry)
 264 {
 265         struct gfs2_inode *dip = GFS2_I(dir);
 266         struct gfs2_sbd *sdp = GFS2_SB(dir);
 267         struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
 268         struct gfs2_holder ghs[2];
 269         int error;
 270
 271         gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
 272         gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + 1);
 273
 274         error = gfs2_glock_nq_m(2, ghs);
 275         if (error)
 276                 goto out;
 277
 278         error = gfs2_unlink_ok(dip, &dentry->d_name, ip);
 279         if (error)
 280                 goto out_gunlock;
 281
 282         error = gfs2_trans_begin(sdp, 2*RES_DINODE + RES_LEAF + RES_RG_BIT, 0);
 283         if (error)
 284                 goto out_gunlock;
 285
 286         error = gfs2_dir_del(dip, &dentry->d_name);
 287         if (error)
 288                 goto out_end_trans;
 289
 290         error = gfs2_change_nlink(ip, -1);
 291
 292 out_end_trans:
 293         gfs2_trans_end(sdp);
 294 out_gunlock:
 295         gfs2_glock_dq_m(2, ghs);
 296 out:
 297         gfs2_holder_uninit(ghs);
 298         gfs2_holder_uninit(ghs + 1);
 299         return error;
 300 }
 301
 302 /**
 303  * gfs2_symlink - Create a symlink
 304  * @dir: The directory to create the symlink in
 305  * @dentry: The dentry to put the symlink in
 306  * @symname: The thing which the link points to
 307  *
 308  * Returns: errno
 309  */
 310
 311 static int gfs2_symlink(struct inode *dir, struct dentry *dentry,
 312                         const char *symname)
 313 {
 314         struct gfs2_inode *dip = GFS2_I(dir), *ip;
 315         struct gfs2_sbd *sdp = GFS2_SB(dir);
 316         struct gfs2_holder ghs[2];
 317         struct inode *inode;
 318         struct buffer_head *dibh;
 319         int size;
 320         int error;
 321
 322         /* Must be stuffed with a null terminator for gfs2_follow_link() */
 323         size = strlen(symname);
 324         if (size > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode) - 1)
 325                 return -ENAMETOOLONG;
 326
 327         gfs2_holder_init(dip->i_gl, 0, 0, ghs);
 328
 329         inode = gfs2_createi(ghs, &dentry->d_name, S_IFLNK | S_IRWXUGO);
 330         if (IS_ERR(inode)) {
 331                 gfs2_holder_uninit(ghs);
 332                 return PTR_ERR(inode);
 333         }
 334
 335         ip = ghs[1].gh_gl->gl_object;
 336
 337         ip->i_di.di_size = size;
 338
 339         error = gfs2_meta_inode_buffer(ip, &dibh);
 340
 341         if (!gfs2_assert_withdraw(sdp, !error)) {
 342                 gfs2_dinode_out(ip, dibh->b_data);
 343                 memcpy(dibh->b_data + sizeof(struct gfs2_dinode), symname,
 344                        size);
 345                 brelse(dibh);
 346         }
 347
 348         gfs2_trans_end(sdp);
 349         if (dip->i_alloc.al_rgd)
 350                 gfs2_inplace_release(dip);
 351         gfs2_quota_unlock(dip);
 352         gfs2_alloc_put(dip);
 353
 354         gfs2_glock_dq_uninit_m(2, ghs);
 355
 356         d_instantiate(dentry, inode);
 357         mark_inode_dirty(inode);
 358
 359         return 0;
 360 }
 361
 362 /**
 363  * gfs2_mkdir - Make a directory
 364  * @dir: The parent directory of the new one
 365  * @dentry: The dentry of the new directory
 366  * @mode: The mode of the new directory
 367  *
 368  * Returns: errno
 369  */
 370
 371 static int gfs2_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 372 {
 373         struct gfs2_inode *dip = GFS2_I(dir), *ip;
 374         struct gfs2_sbd *sdp = GFS2_SB(dir);
 375         struct gfs2_holder ghs[2];
 376         struct inode *inode;
 377         struct buffer_head *dibh;
 378         int error;
 379
 380         gfs2_holder_init(dip->i_gl, 0, 0, ghs);
 381
 382         inode = gfs2_createi(ghs, &dentry->d_name, S_IFDIR | mode);
 383         if (IS_ERR(inode)) {
 384                 gfs2_holder_uninit(ghs);
 385                 return PTR_ERR(inode);
 386         }
 387
 388         ip = ghs[1].gh_gl->gl_object;
 389
 390         ip->i_di.di_nlink = 2;
 391         ip->i_di.di_size = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode);
 392         ip->i_di.di_flags |= GFS2_DIF_JDATA;
 393         ip->i_di.di_payload_format = GFS2_FORMAT_DE;
 394         ip->i_di.di_entries = 2;
 395
 396         error = gfs2_meta_inode_buffer(ip, &dibh);
 397
 398         if (!gfs2_assert_withdraw(sdp, !error)) {
 399                 struct gfs2_dinode *di = (struct gfs2_dinode *)dibh->b_data;
 400                 struct gfs2_dirent *dent = (struct gfs2_dirent *)(di+1);
 401                 struct qstr str;
 402
 403                 gfs2_str2qstr(&str, ".");
 404                 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
 405                 gfs2_qstr2dirent(&str, GFS2_DIRENT_SIZE(str.len), dent);
 406                 dent->de_inum = di->di_num; /* already GFS2 endian */
 407                 dent->de_type = cpu_to_be16(DT_DIR);
 408                 di->di_entries = cpu_to_be32(1);
 409
 410                 gfs2_str2qstr(&str, "..");
 411                 dent = (struct gfs2_dirent *)((char*)dent + GFS2_DIRENT_SIZE(1));
 412                 gfs2_qstr2dirent(&str, dibh->b_size - GFS2_DIRENT_SIZE(1) - sizeof(struct gfs2_dinode), dent);
 413
 414                 gfs2_inum_out(&dip->i_num, &dent->de_inum);
 415                 dent->de_type = cpu_to_be16(DT_DIR);
 416
 417                 gfs2_dinode_out(ip, di);
 418
 419                 brelse(dibh);
 420         }
 421
 422         error = gfs2_change_nlink(dip, +1);
 423         gfs2_assert_withdraw(sdp, !error); /* dip already pinned */
 424
 425         gfs2_trans_end(sdp);
 426         if (dip->i_alloc.al_rgd)
 427                 gfs2_inplace_release(dip);
 428         gfs2_quota_unlock(dip);
 429         gfs2_alloc_put(dip);
 430
 431         gfs2_glock_dq_uninit_m(2, ghs);
 432
 433         d_instantiate(dentry, inode);
 434         mark_inode_dirty(inode);
 435
 436         return 0;
 437 }
 438
 439 /**
 440  * gfs2_rmdir - Remove a directory
 441  * @dir: The parent directory of the directory to be removed
 442  * @dentry: The dentry of the directory to remove
 443  *
 444  * Remove a directory. Call gfs2_rmdiri()
 445  *
 446  * Returns: errno
 447  */
 448
 449 static int gfs2_rmdir(struct inode *dir, struct dentry *dentry)
 450 {
 451         struct gfs2_inode *dip = GFS2_I(dir);
 452         struct gfs2_sbd *sdp = GFS2_SB(dir);
 453         struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
 454         struct gfs2_holder ghs[2];
 455         int error;
 456
 457         gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
 458         gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + 1);
 459
 460         error = gfs2_glock_nq_m(2, ghs);
 461         if (error)
 462                 goto out;
 463
 464         error = gfs2_unlink_ok(dip, &dentry->d_name, ip);
 465         if (error)
 466                 goto out_gunlock;
 467
 468         if (ip->i_di.di_entries < 2) {
 469                 if (gfs2_consist_inode(ip))
 470                         gfs2_dinode_print(ip);
 471                 error = -EIO;
 472                 goto out_gunlock;
 473         }
 474         if (ip->i_di.di_entries > 2) {
 475                 error = -ENOTEMPTY;
 476                 goto out_gunlock;
 477         }
 478
 479         error = gfs2_trans_begin(sdp, 2 * RES_DINODE + 3 * RES_LEAF + RES_RG_BIT, 0);
 480         if (error)
 481                 goto out_gunlock;
 482
 483         error = gfs2_rmdiri(dip, &dentry->d_name, ip);
 484
 485         gfs2_trans_end(sdp);
 486
 487 out_gunlock:
 488         gfs2_glock_dq_m(2, ghs);
 489 out:
 490         gfs2_holder_uninit(ghs);
 491         gfs2_holder_uninit(ghs + 1);
 492         return error;
 493 }
 494
 495 /**
 496  * gfs2_mknod - Make a special file
 497  * @dir: The directory in which the special file will reside
 498  * @dentry: The dentry of the special file
 499  * @mode: The mode of the special file
 500  * @rdev: The device specification of the special file
 501  *
 502  */
 503
 504 static int gfs2_mknod(struct inode *dir, struct dentry *dentry, int mode,
 505                       dev_t dev)
 506 {
 507         struct gfs2_inode *dip = GFS2_I(dir), *ip;
 508         struct gfs2_sbd *sdp = GFS2_SB(dir);
 509         struct gfs2_holder ghs[2];
 510         struct inode *inode;
 511         struct buffer_head *dibh;
 512         u32 major = 0, minor = 0;
 513         int error;
 514
 515         switch (mode & S_IFMT) {
 516         case S_IFBLK:
 517         case S_IFCHR:
 518                 major = MAJOR(dev);
 519                 minor = MINOR(dev);
 520                 break;
 521         case S_IFIFO:
 522         case S_IFSOCK:
 523                 break;
 524         default:
 525                 return -EOPNOTSUPP;
 526         };
 527
 528         gfs2_holder_init(dip->i_gl, 0, 0, ghs);
 529
 530         inode = gfs2_createi(ghs, &dentry->d_name, mode);
 531         if (IS_ERR(inode)) {
 532                 gfs2_holder_uninit(ghs);
 533                 return PTR_ERR(inode);
 534         }
 535
 536         ip = ghs[1].gh_gl->gl_object;
 537
 538         ip->i_di.di_major = major;
 539         ip->i_di.di_minor = minor;
 540
 541         error = gfs2_meta_inode_buffer(ip, &dibh);
 542
 543         if (!gfs2_assert_withdraw(sdp, !error)) {
 544                 gfs2_dinode_out(ip, dibh->b_data);
 545                 brelse(dibh);
 546         }
 547
 548         gfs2_trans_end(sdp);
 549         if (dip->i_alloc.al_rgd)
 550                 gfs2_inplace_release(dip);
 551         gfs2_quota_unlock(dip);
 552         gfs2_alloc_put(dip);
 553
 554         gfs2_glock_dq_uninit_m(2, ghs);
 555
 556         d_instantiate(dentry, inode);
 557         mark_inode_dirty(inode);
 558
 559         return 0;
 560 }
 561
 562 /**
 563  * gfs2_rename - Rename a file
 564  * @odir: Parent directory of old file name
 565  * @odentry: The old dentry of the file
 566  * @ndir: Parent directory of new file name
 567  * @ndentry: The new dentry of the file
 568  *
 569  * Returns: errno
 570  */
 571
 572 static int gfs2_rename(struct inode *odir, struct dentry *odentry,
 573                        struct inode *ndir, struct dentry *ndentry)
 574 {
 575         struct gfs2_inode *odip = GFS2_I(odir);
 576         struct gfs2_inode *ndip = GFS2_I(ndir);
 577         struct gfs2_inode *ip = GFS2_I(odentry->d_inode);
 578         struct gfs2_inode *nip = NULL;
 579         struct gfs2_sbd *sdp = GFS2_SB(odir);
 580         struct gfs2_holder ghs[4], r_gh;
 581         unsigned int num_gh;
 582         int dir_rename = 0;
 583         int alloc_required;
 584         unsigned int x;
 585         int error;
 586
 587         if (ndentry->d_inode) {
 588                 nip = GFS2_I(ndentry->d_inode);
 589                 if (ip == nip)
 590                         return 0;
 591         }
 592
 593         /* Make sure we aren't trying to move a dirctory into it's subdir */
 594
 595         if (S_ISDIR(ip->i_di.di_mode) && odip != ndip) {
 596                 dir_rename = 1;
 597
 598                 error = gfs2_glock_nq_init(sdp->sd_rename_gl,
 599                                            LM_ST_EXCLUSIVE, 0,
 600                                            &r_gh);
 601                 if (error)
 602                         goto out;
 603
 604                 error = gfs2_ok_to_move(ip, ndip);
 605                 if (error)
 606                         goto out_gunlock_r;
 607         }
 608
 609         num_gh = 1;
 610         gfs2_holder_init(odip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
 611         if (odip != ndip) {
 612                 gfs2_holder_init(ndip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
 613                 num_gh++;
 614         }
 615         gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
 616         num_gh++;
 617
 618         if (nip) {
 619                 gfs2_holder_init(nip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
 620                 num_gh++;
 621         }
 622
 623         error = gfs2_glock_nq_m(num_gh, ghs);
 624         if (error)
 625                 goto out_uninit;
 626
 627         /* Check out the old directory */
 628
 629         error = gfs2_unlink_ok(odip, &odentry->d_name, ip);
 630         if (error)
 631                 goto out_gunlock;
 632
 633         /* Check out the new directory */
 634
 635         if (nip) {
 636                 error = gfs2_unlink_ok(ndip, &ndentry->d_name, nip);
 637                 if (error)
 638                         goto out_gunlock;
 639
 640                 if (S_ISDIR(nip->i_di.di_mode)) {
 641                         if (nip->i_di.di_entries < 2) {
 642                                 if (gfs2_consist_inode(nip))
 643                                         gfs2_dinode_print(nip);
 644                                 error = -EIO;
 645                                 goto out_gunlock;
 646                         }
 647                         if (nip->i_di.di_entries > 2) {
 648                                 error = -ENOTEMPTY;
 649                                 goto out_gunlock;
 650                         }
 651                 }
 652         } else {
 653                 error = permission(ndir, MAY_WRITE | MAY_EXEC, NULL);
 654                 if (error)
 655                         goto out_gunlock;
 656
 657                 error = gfs2_dir_search(ndir, &ndentry->d_name, NULL, NULL);
 658                 switch (error) {
 659                 case -ENOENT:
 660                         error = 0;
 661                         break;
 662                 case 0:
 663                         error = -EEXIST;
 664                 default:
 665                         goto out_gunlock;
 666                 };
 667
 668                 if (odip != ndip) {
 669                         if (!ndip->i_di.di_nlink) {
 670                                 error = -EINVAL;
 671                                 goto out_gunlock;
 672                         }
 673                         if (ndip->i_di.di_entries == (u32)-1) {
 674                                 error = -EFBIG;
 675                                 goto out_gunlock;
 676                         }
 677                         if (S_ISDIR(ip->i_di.di_mode) &&
 678                             ndip->i_di.di_nlink == (u32)-1) {
 679                                 error = -EMLINK;
 680                                 goto out_gunlock;
 681                         }
 682                 }
 683         }
 684
 685         /* Check out the dir to be renamed */
 686
 687         if (dir_rename) {
 688                 error = permission(odentry->d_inode, MAY_WRITE, NULL);
 689                 if (error)
 690                         goto out_gunlock;
 691         }
 692
 693         alloc_required = error = gfs2_diradd_alloc_required(ndir, &ndentry->d_name);
 694         if (error < 0)
 695                 goto out_gunlock;
 696         error = 0;
 697
 698         if (alloc_required) {
 699                 struct gfs2_alloc *al = gfs2_alloc_get(ndip);
 700
 701                 error = gfs2_quota_lock(ndip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
 702                 if (error)
 703                         goto out_alloc;
 704
 705                 error = gfs2_quota_check(ndip, ndip->i_di.di_uid,
 706                                          ndip->i_di.di_gid);
 707                 if (error)
 708                         goto out_gunlock_q;
 709
 710                 al->al_requested = sdp->sd_max_dirres;
 711
 712                 error = gfs2_inplace_reserve(ndip);
 713                 if (error)
 714                         goto out_gunlock_q;
 715
 716                 error = gfs2_trans_begin(sdp, sdp->sd_max_dirres +
 717                                          al->al_rgd->rd_ri.ri_length +
 718                                          4 * RES_DINODE + 4 * RES_LEAF +
 719                                          RES_STATFS + RES_QUOTA, 0);
 720                 if (error)
 721                         goto out_ipreserv;
 722         } else {
 723                 error = gfs2_trans_begin(sdp, 4 * RES_DINODE +
 724                                          5 * RES_LEAF, 0);
 725                 if (error)
 726                         goto out_gunlock;
 727         }
 728
 729         /* Remove the target file, if it exists */
 730
 731         if (nip) {
 732                 if (S_ISDIR(nip->i_di.di_mode))
 733                         error = gfs2_rmdiri(ndip, &ndentry->d_name, nip);
 734                 else {
 735                         error = gfs2_dir_del(ndip, &ndentry->d_name);
 736                         if (error)
 737                                 goto out_end_trans;
 738                         error = gfs2_change_nlink(nip, -1);
 739                 }
 740                 if (error)
 741                         goto out_end_trans;
 742         }
 743
 744         if (dir_rename) {
 745                 struct qstr name;
 746                 gfs2_str2qstr(&name, "..");
 747
 748                 error = gfs2_change_nlink(ndip, +1);
 749                 if (error)
 750                         goto out_end_trans;
 751                 error = gfs2_change_nlink(odip, -1);
 752                 if (error)
 753                         goto out_end_trans;
 754
 755                 error = gfs2_dir_mvino(ip, &name, &ndip->i_num, DT_DIR);
 756                 if (error)
 757                         goto out_end_trans;
 758         } else {
 759                 struct buffer_head *dibh;
 760                 error = gfs2_meta_inode_buffer(ip, &dibh);
 761                 if (error)
 762                         goto out_end_trans;
 763                 ip->i_di.di_ctime = get_seconds();
 764                 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
 765                 gfs2_dinode_out(ip, dibh->b_data);
 766                 brelse(dibh);
 767         }
 768
 769         error = gfs2_dir_del(odip, &odentry->d_name);
 770         if (error)
 771                 goto out_end_trans;
 772
 773         error = gfs2_dir_add(ndir, &ndentry->d_name, &ip->i_num,
 774                              IF2DT(ip->i_di.di_mode));
 775         if (error)
 776                 goto out_end_trans;
 777
 778 out_end_trans:
 779         gfs2_trans_end(sdp);
 780 out_ipreserv:
 781         if (alloc_required)
 782                 gfs2_inplace_release(ndip);
 783 out_gunlock_q:
 784         if (alloc_required)
 785                 gfs2_quota_unlock(ndip);
 786 out_alloc:
 787         if (alloc_required)
 788                 gfs2_alloc_put(ndip);
 789 out_gunlock:
 790         gfs2_glock_dq_m(num_gh, ghs);
 791 out_uninit:
 792         for (x = 0; x < num_gh; x++)
 793                 gfs2_holder_uninit(ghs + x);
 794 out_gunlock_r:
 795         if (dir_rename)
 796                 gfs2_glock_dq_uninit(&r_gh);
 797 out:
 798         return error;
 799 }
 800
 801 /**
 802  * gfs2_readlink - Read the value of a symlink
 803  * @dentry: the symlink
 804  * @buf: the buffer to read the symlink data into
 805  * @size: the size of the buffer
 806  *
 807  * Returns: errno
 808  */
 809
 810 static int gfs2_readlink(struct dentry *dentry, char __user *user_buf,
 811                          int user_size)
 812 {
 813         struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
 814         char array[GFS2_FAST_NAME_SIZE], *buf = array;
 815         unsigned int len = GFS2_FAST_NAME_SIZE;
 816         int error;
 817
 818         error = gfs2_readlinki(ip, &buf, &len);
 819         if (error)
 820                 return error;
 821
 822         if (user_size > len - 1)
 823                 user_size = len - 1;
 824
 825         if (copy_to_user(user_buf, buf, user_size))
 826                 error = -EFAULT;
 827         else
 828                 error = user_size;
 829
 830         if (buf != array)
 831                 kfree(buf);
 832
 833         return error;
 834 }
 835
 836 /**
 837  * gfs2_follow_link - Follow a symbolic link
 838  * @dentry: The dentry of the link
 839  * @nd: Data that we pass to vfs_follow_link()
 840  *
 841  * This can handle symlinks of any size. It is optimised for symlinks
 842  * under GFS2_FAST_NAME_SIZE.
 843  *
 844  * Returns: 0 on success or error code
 845  */
 846
 847 static void *gfs2_follow_link(struct dentry *dentry, struct nameidata *nd)
 848 {
 849         struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
 850         char array[GFS2_FAST_NAME_SIZE], *buf = array;
 851         unsigned int len = GFS2_FAST_NAME_SIZE;
 852         int error;
 853
 854         error = gfs2_readlinki(ip, &buf, &len);
 855         if (!error) {
 856                 error = vfs_follow_link(nd, buf);
 857                 if (buf != array)
 858                         kfree(buf);
 859         }
 860
 861         return ERR_PTR(error);
 862 }
 863
 864 /**
 865  * gfs2_permission -
 866  * @inode:
 867  * @mask:
 868  * @nd: passed from Linux VFS, ignored by us
 869  *
 870  * Returns: errno
 871  */
 872
 873 static int gfs2_permission(struct inode *inode, int mask, struct nameidata *nd)
 874 {
 875         struct gfs2_inode *ip = GFS2_I(inode);
 876         struct gfs2_holder i_gh;
 877         int error;
 878
 879         if (ip->i_vn == ip->i_gl->gl_vn)
 880                 return generic_permission(inode, mask, gfs2_check_acl);
 881
 882         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
 883         if (!error) {
 884                 error = generic_permission(inode, mask, gfs2_check_acl_locked);
 885                 gfs2_glock_dq_uninit(&i_gh);
 886         }
 887
 888         return error;
 889 }
 890
 891 static int setattr_size(struct inode *inode, struct iattr *attr)
 892 {
 893         struct gfs2_inode *ip = GFS2_I(inode);
 894         int error;
 895
 896         if (attr->ia_size != ip->i_di.di_size) {
 897                 error = vmtruncate(inode, attr->ia_size);
 898                 if (error)
 899                         return error;
 900         }
 901
 902         error = gfs2_truncatei(ip, attr->ia_size);
 903         if (error)
 904                 return error;
 905
 906         return error;
 907 }
 908
 909 static int setattr_chown(struct inode *inode, struct iattr *attr)
 910 {
 911         struct gfs2_inode *ip = GFS2_I(inode);
 912         struct gfs2_sbd *sdp = GFS2_SB(inode);
 913         struct buffer_head *dibh;
 914         u32 ouid, ogid, nuid, ngid;
 915         int error;
 916
 917         ouid = ip->i_di.di_uid;
 918         ogid = ip->i_di.di_gid;
 919         nuid = attr->ia_uid;
 920         ngid = attr->ia_gid;
 921
 922         if (!(attr->ia_valid & ATTR_UID) || ouid == nuid)
 923                 ouid = nuid = NO_QUOTA_CHANGE;
 924         if (!(attr->ia_valid & ATTR_GID) || ogid == ngid)
 925                 ogid = ngid = NO_QUOTA_CHANGE;
 926
 927         gfs2_alloc_get(ip);
 928
 929         error = gfs2_quota_lock(ip, nuid, ngid);
 930         if (error)
 931                 goto out_alloc;
 932
 933         if (ouid != NO_QUOTA_CHANGE || ogid != NO_QUOTA_CHANGE) {
 934                 error = gfs2_quota_check(ip, nuid, ngid);
 935                 if (error)
 936                         goto out_gunlock_q;
 937         }
 938
 939         error = gfs2_trans_begin(sdp, RES_DINODE + 2 * RES_QUOTA, 0);
 940         if (error)
 941                 goto out_gunlock_q;
 942
 943         error = gfs2_meta_inode_buffer(ip, &dibh);
 944         if (error)
 945                 goto out_end_trans;
 946
 947         error = inode_setattr(inode, attr);
 948         gfs2_assert_warn(sdp, !error);
 949         gfs2_inode_attr_out(ip);
 950
 951         gfs2_trans_add_bh(ip->i_gl, dibh, 1);
 952         gfs2_dinode_out(ip, dibh->b_data);
 953         brelse(dibh);
 954
 955         if (ouid != NO_QUOTA_CHANGE || ogid != NO_QUOTA_CHANGE) {
 956                 gfs2_quota_change(ip, -ip->i_di.di_blocks, ouid, ogid);
 957                 gfs2_quota_change(ip, ip->i_di.di_blocks, nuid, ngid);
 958         }
 959
 960 out_end_trans:
 961         gfs2_trans_end(sdp);
 962 out_gunlock_q:
 963         gfs2_quota_unlock(ip);
 964 out_alloc:
 965         gfs2_alloc_put(ip);
 966         return error;
 967 }
 968
 969 /**
 970  * gfs2_setattr - Change attributes on an inode
 971  * @dentry: The dentry which is changing
 972  * @attr: The structure describing the change
 973  *
 974  * The VFS layer wants to change one or more of an inodes attributes.  Write
 975  * that change out to disk.
 976  *
 977  * Returns: errno
 978  */
 979
 980 static int gfs2_setattr(struct dentry *dentry, struct iattr *attr)
 981 {
 982         struct inode *inode = dentry->d_inode;
 983         struct gfs2_inode *ip = GFS2_I(inode);
 984         struct gfs2_holder i_gh;
 985         int error;
 986
 987         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
 988         if (error)
 989                 return error;
 990
 991         error = -EPERM;
 992         if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
 993                 goto out;
 994
 995         error = inode_change_ok(inode, attr);
 996         if (error)
 997                 goto out;
 998
 999         if (attr->ia_valid & ATTR_SIZE)
1000                 error = setattr_size(inode, attr);
1001         else if (attr->ia_valid & (ATTR_UID | ATTR_GID))
1002                 error = setattr_chown(inode, attr);
1003         else if ((attr->ia_valid & ATTR_MODE) && IS_POSIXACL(inode))
1004                 error = gfs2_acl_chmod(ip, attr);
1005         else
1006                 error = gfs2_setattr_simple(ip, attr);
1007
1008 out:
1009         gfs2_glock_dq_uninit(&i_gh);
1010         if (!error)
1011                 mark_inode_dirty(inode);
1012         return error;
1013 }
1014
1015 /**
1016  * gfs2_getattr - Read out an inode's attributes
1017  * @mnt: The vfsmount the inode is being accessed from
1018  * @dentry: The dentry to stat
1019  * @stat: The inode's stats
1020  *
1021  * Returns: errno
1022  */
1023
1024 static int gfs2_getattr(struct vfsmount *mnt, struct dentry *dentry,
1025                         struct kstat *stat)
1026 {
1027         struct inode *inode = dentry->d_inode;
1028         struct gfs2_inode *ip = GFS2_I(inode);
1029         struct gfs2_holder gh;
1030         int error;
1031
1032         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
1033         if (!error) {
1034                 generic_fillattr(inode, stat);
1035                 gfs2_glock_dq_uninit(&gh);
1036         }
1037
1038         return error;
1039 }
1040
1041 static int gfs2_setxattr(struct dentry *dentry, const char *name,
1042                          const void *data, size_t size, int flags)
1043 {
1044         struct inode *inode = dentry->d_inode;
1045         struct gfs2_ea_request er;
1046
1047         memset(&er, 0, sizeof(struct gfs2_ea_request));
1048         er.er_type = gfs2_ea_name2type(name, &er.er_name);
1049         if (er.er_type == GFS2_EATYPE_UNUSED)
1050                 return -EOPNOTSUPP;
1051         er.er_data = (char *)data;
1052         er.er_name_len = strlen(er.er_name);
1053         er.er_data_len = size;
1054         er.er_flags = flags;
1055
1056         gfs2_assert_warn(GFS2_SB(inode), !(er.er_flags & GFS2_ERF_MODE));
1057
1058         return gfs2_ea_set(GFS2_I(inode), &er);
1059 }
1060
1061 static ssize_t gfs2_getxattr(struct dentry *dentry, const char *name,
1062                              void *data, size_t size)
1063 {
1064         struct gfs2_ea_request er;
1065
1066         memset(&er, 0, sizeof(struct gfs2_ea_request));
1067         er.er_type = gfs2_ea_name2type(name, &er.er_name);
1068         if (er.er_type == GFS2_EATYPE_UNUSED)
1069                 return -EOPNOTSUPP;
1070         er.er_data = data;
1071         er.er_name_len = strlen(er.er_name);
1072         er.er_data_len = size;
1073
1074         return gfs2_ea_get(GFS2_I(dentry->d_inode), &er);
1075 }
1076
1077 static ssize_t gfs2_listxattr(struct dentry *dentry, char *buffer, size_t size)
1078 {
1079         struct gfs2_ea_request er;
1080
1081         memset(&er, 0, sizeof(struct gfs2_ea_request));
1082         er.er_data = (size) ? buffer : NULL;
1083         er.er_data_len = size;
1084
1085         return gfs2_ea_list(GFS2_I(dentry->d_inode), &er);
1086 }
1087
1088 static int gfs2_removexattr(struct dentry *dentry, const char *name)
1089 {
1090         struct gfs2_ea_request er;
1091
1092         memset(&er, 0, sizeof(struct gfs2_ea_request));
1093         er.er_type = gfs2_ea_name2type(name, &er.er_name);
1094         if (er.er_type == GFS2_EATYPE_UNUSED)
1095                 return -EOPNOTSUPP;
1096         er.er_name_len = strlen(er.er_name);
1097
1098         return gfs2_ea_remove(GFS2_I(dentry->d_inode), &er);
1099 }
1100
1101 struct inode_operations gfs2_file_iops = {
1102         .permission = gfs2_permission,
1103         .setattr = gfs2_setattr,
1104         .getattr = gfs2_getattr,
1105         .setxattr = gfs2_setxattr,
1106         .getxattr = gfs2_getxattr,
1107         .listxattr = gfs2_listxattr,
1108         .removexattr = gfs2_removexattr,
1109 };
1110
1111 struct inode_operations gfs2_dev_iops = {
1112         .permission = gfs2_permission,
1113         .setattr = gfs2_setattr,
1114         .getattr = gfs2_getattr,
1115         .setxattr = gfs2_setxattr,
1116         .getxattr = gfs2_getxattr,
1117         .listxattr = gfs2_listxattr,
1118         .removexattr = gfs2_removexattr,
1119 };
1120
1121 struct inode_operations gfs2_dir_iops = {
1122         .create = gfs2_create,
1123         .lookup = gfs2_lookup,
1124         .link = gfs2_link,
1125         .unlink = gfs2_unlink,
1126         .symlink = gfs2_symlink,
1127         .mkdir = gfs2_mkdir,
1128         .rmdir = gfs2_rmdir,
1129         .mknod = gfs2_mknod,
1130         .rename = gfs2_rename,
1131         .permission = gfs2_permission,
1132         .setattr = gfs2_setattr,
1133         .getattr = gfs2_getattr,
1134         .setxattr = gfs2_setxattr,
1135         .getxattr = gfs2_getxattr,
1136         .listxattr = gfs2_listxattr,
1137         .removexattr = gfs2_removexattr,
1138 };
1139
1140 struct inode_operations gfs2_symlink_iops = {
1141         .readlink = gfs2_readlink,
1142         .follow_link = gfs2_follow_link,
1143         .permission = gfs2_permission,
1144         .setattr = gfs2_setattr,
1145         .getattr = gfs2_getattr,
1146         .setxattr = gfs2_setxattr,
1147         .getxattr = gfs2_getxattr,
1148         .listxattr = gfs2_listxattr,
1149         .removexattr = gfs2_removexattr,
1150 };
1151