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, 0);
  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(inode->i_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_inode.i_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_inode.i_nlink)
 182                 goto out_gunlock;
 183         error = -EMLINK;
 184         if (ip->i_inode.i_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_inode.i_uid, dip->i_inode.i_gid);
 200                 if (error)
 201                         goto out_gunlock_q;
 202
 203                 al->al_requested = sdp->sd_max_dirres;
 204
 205                 error = gfs2_inplace_reserve(dip);
 206                 if (error)
 207                         goto out_gunlock_q;
 208
 209                 error = gfs2_trans_begin(sdp, sdp->sd_max_dirres +
 210                                          al->al_rgd->rd_ri.ri_length +
 211                                          2 * RES_DINODE + RES_STATFS +
 212                                          RES_QUOTA, 0);
 213                 if (error)
 214                         goto out_ipres;
 215         } else {
 216                 error = gfs2_trans_begin(sdp, 2 * RES_DINODE + RES_LEAF, 0);
 217                 if (error)
 218                         goto out_ipres;
 219         }
 220
 221         error = gfs2_dir_add(dir, &dentry->d_name, &ip->i_num,
 222                              IF2DT(inode->i_mode));
 223         if (error)
 224                 goto out_end_trans;
 225
 226         error = gfs2_change_nlink(ip, +1);
 227
 228 out_end_trans:
 229         gfs2_trans_end(sdp);
 230 out_ipres:
 231         if (alloc_required)
 232                 gfs2_inplace_release(dip);
 233 out_gunlock_q:
 234         if (alloc_required)
 235                 gfs2_quota_unlock(dip);
 236 out_alloc:
 237         if (alloc_required)
 238                 gfs2_alloc_put(dip);
 239 out_gunlock:
 240         gfs2_glock_dq_m(2, ghs);
 241 out:
 242         gfs2_holder_uninit(ghs);
 243         gfs2_holder_uninit(ghs + 1);
 244         if (!error) {
 245                 atomic_inc(&inode->i_count);
 246                 d_instantiate(dentry, inode);
 247                 mark_inode_dirty(inode);
 248         }
 249         return error;
 250 }
 251
 252 /**
 253  * gfs2_unlink - Unlink a file
 254  * @dir: The inode of the directory containing the file to unlink
 255  * @dentry: The file itself
 256  *
 257  * Unlink a file.  Call gfs2_unlinki()
 258  *
 259  * Returns: errno
 260  */
 261
 262 static int gfs2_unlink(struct inode *dir, struct dentry *dentry)
 263 {
 264         struct gfs2_inode *dip = GFS2_I(dir);
 265         struct gfs2_sbd *sdp = GFS2_SB(dir);
 266         struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
 267         struct gfs2_holder ghs[2];
 268         int error;
 269
 270         gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
 271         gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + 1);
 272
 273         error = gfs2_glock_nq_m(2, ghs);
 274         if (error)
 275                 goto out;
 276
 277         error = gfs2_unlink_ok(dip, &dentry->d_name, ip);
 278         if (error)
 279                 goto out_gunlock;
 280
 281         error = gfs2_trans_begin(sdp, 2*RES_DINODE + RES_LEAF + RES_RG_BIT, 0);
 282         if (error)
 283                 goto out_gunlock;
 284
 285         error = gfs2_dir_del(dip, &dentry->d_name);
 286         if (error)
 287                 goto out_end_trans;
 288
 289         error = gfs2_change_nlink(ip, -1);
 290
 291 out_end_trans:
 292         gfs2_trans_end(sdp);
 293 out_gunlock:
 294         gfs2_glock_dq_m(2, ghs);
 295 out:
 296         gfs2_holder_uninit(ghs);
 297         gfs2_holder_uninit(ghs + 1);
 298         return error;
 299 }
 300
 301 /**
 302  * gfs2_symlink - Create a symlink
 303  * @dir: The directory to create the symlink in
 304  * @dentry: The dentry to put the symlink in
 305  * @symname: The thing which the link points to
 306  *
 307  * Returns: errno
 308  */
 309
 310 static int gfs2_symlink(struct inode *dir, struct dentry *dentry,
 311                         const char *symname)
 312 {
 313         struct gfs2_inode *dip = GFS2_I(dir), *ip;
 314         struct gfs2_sbd *sdp = GFS2_SB(dir);
 315         struct gfs2_holder ghs[2];
 316         struct inode *inode;
 317         struct buffer_head *dibh;
 318         int size;
 319         int error;
 320
 321         /* Must be stuffed with a null terminator for gfs2_follow_link() */
 322         size = strlen(symname);
 323         if (size > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode) - 1)
 324                 return -ENAMETOOLONG;
 325
 326         gfs2_holder_init(dip->i_gl, 0, 0, ghs);
 327
 328         inode = gfs2_createi(ghs, &dentry->d_name, S_IFLNK | S_IRWXUGO, 0);
 329         if (IS_ERR(inode)) {
 330                 gfs2_holder_uninit(ghs);
 331                 return PTR_ERR(inode);
 332         }
 333
 334         ip = ghs[1].gh_gl->gl_object;
 335
 336         ip->i_di.di_size = size;
 337
 338         error = gfs2_meta_inode_buffer(ip, &dibh);
 339
 340         if (!gfs2_assert_withdraw(sdp, !error)) {
 341                 gfs2_dinode_out(ip, dibh->b_data);
 342                 memcpy(dibh->b_data + sizeof(struct gfs2_dinode), symname,
 343                        size);
 344                 brelse(dibh);
 345         }
 346
 347         gfs2_trans_end(sdp);
 348         if (dip->i_alloc.al_rgd)
 349                 gfs2_inplace_release(dip);
 350         gfs2_quota_unlock(dip);
 351         gfs2_alloc_put(dip);
 352
 353         gfs2_glock_dq_uninit_m(2, ghs);
 354
 355         d_instantiate(dentry, inode);
 356         mark_inode_dirty(inode);
 357
 358         return 0;
 359 }
 360
 361 /**
 362  * gfs2_mkdir - Make a directory
 363  * @dir: The parent directory of the new one
 364  * @dentry: The dentry of the new directory
 365  * @mode: The mode of the new directory
 366  *
 367  * Returns: errno
 368  */
 369
 370 static int gfs2_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 371 {
 372         struct gfs2_inode *dip = GFS2_I(dir), *ip;
 373         struct gfs2_sbd *sdp = GFS2_SB(dir);
 374         struct gfs2_holder ghs[2];
 375         struct inode *inode;
 376         struct buffer_head *dibh;
 377         int error;
 378
 379         gfs2_holder_init(dip->i_gl, 0, 0, ghs);
 380
 381         inode = gfs2_createi(ghs, &dentry->d_name, S_IFDIR | mode, 0);
 382         if (IS_ERR(inode)) {
 383                 gfs2_holder_uninit(ghs);
 384                 return PTR_ERR(inode);
 385         }
 386
 387         ip = ghs[1].gh_gl->gl_object;
 388
 389         ip->i_inode.i_nlink = 2;
 390         ip->i_di.di_size = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode);
 391         ip->i_di.di_flags |= GFS2_DIF_JDATA;
 392         ip->i_di.di_entries = 2;
 393
 394         error = gfs2_meta_inode_buffer(ip, &dibh);
 395
 396         if (!gfs2_assert_withdraw(sdp, !error)) {
 397                 struct gfs2_dinode *di = (struct gfs2_dinode *)dibh->b_data;
 398                 struct gfs2_dirent *dent = (struct gfs2_dirent *)(di+1);
 399                 struct qstr str;
 400
 401                 gfs2_str2qstr(&str, ".");
 402                 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
 403                 gfs2_qstr2dirent(&str, GFS2_DIRENT_SIZE(str.len), dent);
 404                 dent->de_inum = di->di_num; /* already GFS2 endian */
 405                 dent->de_type = cpu_to_be16(DT_DIR);
 406                 di->di_entries = cpu_to_be32(1);
 407
 408                 gfs2_str2qstr(&str, "..");
 409                 dent = (struct gfs2_dirent *)((char*)dent + GFS2_DIRENT_SIZE(1));
 410                 gfs2_qstr2dirent(&str, dibh->b_size - GFS2_DIRENT_SIZE(1) - sizeof(struct gfs2_dinode), dent);
 411
 412                 gfs2_inum_out(&dip->i_num, &dent->de_inum);
 413                 dent->de_type = cpu_to_be16(DT_DIR);
 414
 415                 gfs2_dinode_out(ip, di);
 416
 417                 brelse(dibh);
 418         }
 419
 420         error = gfs2_change_nlink(dip, +1);
 421         gfs2_assert_withdraw(sdp, !error); /* dip already pinned */
 422
 423         gfs2_trans_end(sdp);
 424         if (dip->i_alloc.al_rgd)
 425                 gfs2_inplace_release(dip);
 426         gfs2_quota_unlock(dip);
 427         gfs2_alloc_put(dip);
 428
 429         gfs2_glock_dq_uninit_m(2, ghs);
 430
 431         d_instantiate(dentry, inode);
 432         mark_inode_dirty(inode);
 433
 434         return 0;
 435 }
 436
 437 /**
 438  * gfs2_rmdir - Remove a directory
 439  * @dir: The parent directory of the directory to be removed
 440  * @dentry: The dentry of the directory to remove
 441  *
 442  * Remove a directory. Call gfs2_rmdiri()
 443  *
 444  * Returns: errno
 445  */
 446
 447 static int gfs2_rmdir(struct inode *dir, struct dentry *dentry)
 448 {
 449         struct gfs2_inode *dip = GFS2_I(dir);
 450         struct gfs2_sbd *sdp = GFS2_SB(dir);
 451         struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
 452         struct gfs2_holder ghs[2];
 453         int error;
 454
 455         gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
 456         gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + 1);
 457
 458         error = gfs2_glock_nq_m(2, ghs);
 459         if (error)
 460                 goto out;
 461
 462         error = gfs2_unlink_ok(dip, &dentry->d_name, ip);
 463         if (error)
 464                 goto out_gunlock;
 465
 466         if (ip->i_di.di_entries < 2) {
 467                 if (gfs2_consist_inode(ip))
 468                         gfs2_dinode_print(ip);
 469                 error = -EIO;
 470                 goto out_gunlock;
 471         }
 472         if (ip->i_di.di_entries > 2) {
 473                 error = -ENOTEMPTY;
 474                 goto out_gunlock;
 475         }
 476
 477         error = gfs2_trans_begin(sdp, 2 * RES_DINODE + 3 * RES_LEAF + RES_RG_BIT, 0);
 478         if (error)
 479                 goto out_gunlock;
 480
 481         error = gfs2_rmdiri(dip, &dentry->d_name, ip);
 482
 483         gfs2_trans_end(sdp);
 484
 485 out_gunlock:
 486         gfs2_glock_dq_m(2, ghs);
 487 out:
 488         gfs2_holder_uninit(ghs);
 489         gfs2_holder_uninit(ghs + 1);
 490         return error;
 491 }
 492
 493 /**
 494  * gfs2_mknod - Make a special file
 495  * @dir: The directory in which the special file will reside
 496  * @dentry: The dentry of the special file
 497  * @mode: The mode of the special file
 498  * @rdev: The device specification of the special file
 499  *
 500  */
 501
 502 static int gfs2_mknod(struct inode *dir, struct dentry *dentry, int mode,
 503                       dev_t dev)
 504 {
 505         struct gfs2_inode *dip = GFS2_I(dir);
 506         struct gfs2_sbd *sdp = GFS2_SB(dir);
 507         struct gfs2_holder ghs[2];
 508         struct inode *inode;
 509
 510         gfs2_holder_init(dip->i_gl, 0, 0, ghs);
 511
 512         inode = gfs2_createi(ghs, &dentry->d_name, mode, dev);
 513         if (IS_ERR(inode)) {
 514                 gfs2_holder_uninit(ghs);
 515                 return PTR_ERR(inode);
 516         }
 517
 518         gfs2_trans_end(sdp);
 519         if (dip->i_alloc.al_rgd)
 520                 gfs2_inplace_release(dip);
 521         gfs2_quota_unlock(dip);
 522         gfs2_alloc_put(dip);
 523
 524         gfs2_glock_dq_uninit_m(2, ghs);
 525
 526         d_instantiate(dentry, inode);
 527         mark_inode_dirty(inode);
 528
 529         return 0;
 530 }
 531
 532 /**
 533  * gfs2_rename - Rename a file
 534  * @odir: Parent directory of old file name
 535  * @odentry: The old dentry of the file
 536  * @ndir: Parent directory of new file name
 537  * @ndentry: The new dentry of the file
 538  *
 539  * Returns: errno
 540  */
 541
 542 static int gfs2_rename(struct inode *odir, struct dentry *odentry,
 543                        struct inode *ndir, struct dentry *ndentry)
 544 {
 545         struct gfs2_inode *odip = GFS2_I(odir);
 546         struct gfs2_inode *ndip = GFS2_I(ndir);
 547         struct gfs2_inode *ip = GFS2_I(odentry->d_inode);
 548         struct gfs2_inode *nip = NULL;
 549         struct gfs2_sbd *sdp = GFS2_SB(odir);
 550         struct gfs2_holder ghs[4], r_gh;
 551         unsigned int num_gh;
 552         int dir_rename = 0;
 553         int alloc_required;
 554         unsigned int x;
 555         int error;
 556
 557         if (ndentry->d_inode) {
 558                 nip = GFS2_I(ndentry->d_inode);
 559                 if (ip == nip)
 560                         return 0;
 561         }
 562
 563         /* Make sure we aren't trying to move a dirctory into it's subdir */
 564
 565         if (S_ISDIR(ip->i_inode.i_mode) && odip != ndip) {
 566                 dir_rename = 1;
 567
 568                 error = gfs2_glock_nq_init(sdp->sd_rename_gl, LM_ST_EXCLUSIVE, 0,
 569                                            &r_gh);
 570                 if (error)
 571                         goto out;
 572
 573                 error = gfs2_ok_to_move(ip, ndip);
 574                 if (error)
 575                         goto out_gunlock_r;
 576         }
 577
 578         num_gh = 1;
 579         gfs2_holder_init(odip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
 580         if (odip != ndip) {
 581                 gfs2_holder_init(ndip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
 582                 num_gh++;
 583         }
 584         gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
 585         num_gh++;
 586
 587         if (nip) {
 588                 gfs2_holder_init(nip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
 589                 num_gh++;
 590         }
 591
 592         error = gfs2_glock_nq_m(num_gh, ghs);
 593         if (error)
 594                 goto out_uninit;
 595
 596         /* Check out the old directory */
 597
 598         error = gfs2_unlink_ok(odip, &odentry->d_name, ip);
 599         if (error)
 600                 goto out_gunlock;
 601
 602         /* Check out the new directory */
 603
 604         if (nip) {
 605                 error = gfs2_unlink_ok(ndip, &ndentry->d_name, nip);
 606                 if (error)
 607                         goto out_gunlock;
 608
 609                 if (S_ISDIR(nip->i_inode.i_mode)) {
 610                         if (nip->i_di.di_entries < 2) {
 611                                 if (gfs2_consist_inode(nip))
 612                                         gfs2_dinode_print(nip);
 613                                 error = -EIO;
 614                                 goto out_gunlock;
 615                         }
 616                         if (nip->i_di.di_entries > 2) {
 617                                 error = -ENOTEMPTY;
 618                                 goto out_gunlock;
 619                         }
 620                 }
 621         } else {
 622                 error = permission(ndir, MAY_WRITE | MAY_EXEC, NULL);
 623                 if (error)
 624                         goto out_gunlock;
 625
 626                 error = gfs2_dir_search(ndir, &ndentry->d_name, NULL, NULL);
 627                 switch (error) {
 628                 case -ENOENT:
 629                         error = 0;
 630                         break;
 631                 case 0:
 632                         error = -EEXIST;
 633                 default:
 634                         goto out_gunlock;
 635                 };
 636
 637                 if (odip != ndip) {
 638                         if (!ndip->i_inode.i_nlink) {
 639                                 error = -EINVAL;
 640                                 goto out_gunlock;
 641                         }
 642                         if (ndip->i_di.di_entries == (u32)-1) {
 643                                 error = -EFBIG;
 644                                 goto out_gunlock;
 645                         }
 646                         if (S_ISDIR(ip->i_inode.i_mode) &&
 647                             ndip->i_inode.i_nlink == (u32)-1) {
 648                                 error = -EMLINK;
 649                                 goto out_gunlock;
 650                         }
 651                 }
 652         }
 653
 654         /* Check out the dir to be renamed */
 655
 656         if (dir_rename) {
 657                 error = permission(odentry->d_inode, MAY_WRITE, NULL);
 658                 if (error)
 659                         goto out_gunlock;
 660         }
 661
 662         alloc_required = error = gfs2_diradd_alloc_required(ndir, &ndentry->d_name);
 663         if (error < 0)
 664                 goto out_gunlock;
 665         error = 0;
 666
 667         if (alloc_required) {
 668                 struct gfs2_alloc *al = gfs2_alloc_get(ndip);
 669
 670                 error = gfs2_quota_lock(ndip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
 671                 if (error)
 672                         goto out_alloc;
 673
 674                 error = gfs2_quota_check(ndip, ndip->i_inode.i_uid, ndip->i_inode.i_gid);
 675                 if (error)
 676                         goto out_gunlock_q;
 677
 678                 al->al_requested = sdp->sd_max_dirres;
 679
 680                 error = gfs2_inplace_reserve(ndip);
 681                 if (error)
 682                         goto out_gunlock_q;
 683
 684                 error = gfs2_trans_begin(sdp, sdp->sd_max_dirres +
 685                                          al->al_rgd->rd_ri.ri_length +
 686                                          4 * RES_DINODE + 4 * RES_LEAF +
 687                                          RES_STATFS + RES_QUOTA, 0);
 688                 if (error)
 689                         goto out_ipreserv;
 690         } else {
 691                 error = gfs2_trans_begin(sdp, 4 * RES_DINODE +
 692                                          5 * RES_LEAF, 0);
 693                 if (error)
 694                         goto out_gunlock;
 695         }
 696
 697         /* Remove the target file, if it exists */
 698
 699         if (nip) {
 700                 if (S_ISDIR(nip->i_inode.i_mode))
 701                         error = gfs2_rmdiri(ndip, &ndentry->d_name, nip);
 702                 else {
 703                         error = gfs2_dir_del(ndip, &ndentry->d_name);
 704                         if (error)
 705                                 goto out_end_trans;
 706                         error = gfs2_change_nlink(nip, -1);
 707                 }
 708                 if (error)
 709                         goto out_end_trans;
 710         }
 711
 712         if (dir_rename) {
 713                 struct qstr name;
 714                 gfs2_str2qstr(&name, "..");
 715
 716                 error = gfs2_change_nlink(ndip, +1);
 717                 if (error)
 718                         goto out_end_trans;
 719                 error = gfs2_change_nlink(odip, -1);
 720                 if (error)
 721                         goto out_end_trans;
 722
 723                 error = gfs2_dir_mvino(ip, &name, &ndip->i_num, DT_DIR);
 724                 if (error)
 725                         goto out_end_trans;
 726         } else {
 727                 struct buffer_head *dibh;
 728                 error = gfs2_meta_inode_buffer(ip, &dibh);
 729                 if (error)
 730                         goto out_end_trans;
 731                 ip->i_inode.i_ctime.tv_sec = get_seconds();
 732                 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
 733                 gfs2_dinode_out(ip, dibh->b_data);
 734                 brelse(dibh);
 735         }
 736
 737         error = gfs2_dir_del(odip, &odentry->d_name);
 738         if (error)
 739                 goto out_end_trans;
 740
 741         error = gfs2_dir_add(ndir, &ndentry->d_name, &ip->i_num,
 742                              IF2DT(ip->i_inode.i_mode));
 743         if (error)
 744                 goto out_end_trans;
 745
 746 out_end_trans:
 747         gfs2_trans_end(sdp);
 748 out_ipreserv:
 749         if (alloc_required)
 750                 gfs2_inplace_release(ndip);
 751 out_gunlock_q:
 752         if (alloc_required)
 753                 gfs2_quota_unlock(ndip);
 754 out_alloc:
 755         if (alloc_required)
 756                 gfs2_alloc_put(ndip);
 757 out_gunlock:
 758         gfs2_glock_dq_m(num_gh, ghs);
 759 out_uninit:
 760         for (x = 0; x < num_gh; x++)
 761                 gfs2_holder_uninit(ghs + x);
 762 out_gunlock_r:
 763         if (dir_rename)
 764                 gfs2_glock_dq_uninit(&r_gh);
 765 out:
 766         return error;
 767 }
 768
 769 /**
 770  * gfs2_readlink - Read the value of a symlink
 771  * @dentry: the symlink
 772  * @buf: the buffer to read the symlink data into
 773  * @size: the size of the buffer
 774  *
 775  * Returns: errno
 776  */
 777
 778 static int gfs2_readlink(struct dentry *dentry, char __user *user_buf,
 779                          int user_size)
 780 {
 781         struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
 782         char array[GFS2_FAST_NAME_SIZE], *buf = array;
 783         unsigned int len = GFS2_FAST_NAME_SIZE;
 784         int error;
 785
 786         error = gfs2_readlinki(ip, &buf, &len);
 787         if (error)
 788                 return error;
 789
 790         if (user_size > len - 1)
 791                 user_size = len - 1;
 792
 793         if (copy_to_user(user_buf, buf, user_size))
 794                 error = -EFAULT;
 795         else
 796                 error = user_size;
 797
 798         if (buf != array)
 799                 kfree(buf);
 800
 801         return error;
 802 }
 803
 804 /**
 805  * gfs2_follow_link - Follow a symbolic link
 806  * @dentry: The dentry of the link
 807  * @nd: Data that we pass to vfs_follow_link()
 808  *
 809  * This can handle symlinks of any size. It is optimised for symlinks
 810  * under GFS2_FAST_NAME_SIZE.
 811  *
 812  * Returns: 0 on success or error code
 813  */
 814
 815 static void *gfs2_follow_link(struct dentry *dentry, struct nameidata *nd)
 816 {
 817         struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
 818         char array[GFS2_FAST_NAME_SIZE], *buf = array;
 819         unsigned int len = GFS2_FAST_NAME_SIZE;
 820         int error;
 821
 822         error = gfs2_readlinki(ip, &buf, &len);
 823         if (!error) {
 824                 error = vfs_follow_link(nd, buf);
 825                 if (buf != array)
 826                         kfree(buf);
 827         }
 828
 829         return ERR_PTR(error);
 830 }
 831
 832 /**
 833  * gfs2_permission -
 834  * @inode:
 835  * @mask:
 836  * @nd: passed from Linux VFS, ignored by us
 837  *
 838  * This may be called from the VFS directly, or from within GFS2 with the
 839  * inode locked, so we look to see if the glock is already locked and only
 840  * lock the glock if its not already been done.
 841  *
 842  * Returns: errno
 843  */
 844
 845 static int gfs2_permission(struct inode *inode, int mask, struct nameidata *nd)
 846 {
 847         struct gfs2_inode *ip = GFS2_I(inode);
 848         struct gfs2_holder i_gh;
 849         int error;
 850         int unlock = 0;
 851
 852         if (gfs2_glock_is_locked_by_me(ip->i_gl) == 0) {
 853                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
 854                 if (error)
 855                         return error;
 856                 unlock = 1;
 857         }
 858
 859         error = generic_permission(inode, mask, gfs2_check_acl);
 860         if (unlock)
 861                 gfs2_glock_dq_uninit(&i_gh);
 862
 863         return error;
 864 }
 865
 866 static int setattr_size(struct inode *inode, struct iattr *attr)
 867 {
 868         struct gfs2_inode *ip = GFS2_I(inode);
 869         int error;
 870
 871         if (attr->ia_size != ip->i_di.di_size) {
 872                 error = vmtruncate(inode, attr->ia_size);
 873                 if (error)
 874                         return error;
 875         }
 876
 877         error = gfs2_truncatei(ip, attr->ia_size);
 878         if (error)
 879                 return error;
 880
 881         return error;
 882 }
 883
 884 static int setattr_chown(struct inode *inode, struct iattr *attr)
 885 {
 886         struct gfs2_inode *ip = GFS2_I(inode);
 887         struct gfs2_sbd *sdp = GFS2_SB(inode);
 888         struct buffer_head *dibh;
 889         u32 ouid, ogid, nuid, ngid;
 890         int error;
 891
 892         ouid = inode->i_uid;
 893         ogid = inode->i_gid;
 894         nuid = attr->ia_uid;
 895         ngid = attr->ia_gid;
 896
 897         if (!(attr->ia_valid & ATTR_UID) || ouid == nuid)
 898                 ouid = nuid = NO_QUOTA_CHANGE;
 899         if (!(attr->ia_valid & ATTR_GID) || ogid == ngid)
 900                 ogid = ngid = NO_QUOTA_CHANGE;
 901
 902         gfs2_alloc_get(ip);
 903
 904         error = gfs2_quota_lock(ip, nuid, ngid);
 905         if (error)
 906                 goto out_alloc;
 907
 908         if (ouid != NO_QUOTA_CHANGE || ogid != NO_QUOTA_CHANGE) {
 909                 error = gfs2_quota_check(ip, nuid, ngid);
 910                 if (error)
 911                         goto out_gunlock_q;
 912         }
 913
 914         error = gfs2_trans_begin(sdp, RES_DINODE + 2 * RES_QUOTA, 0);
 915         if (error)
 916                 goto out_gunlock_q;
 917
 918         error = gfs2_meta_inode_buffer(ip, &dibh);
 919         if (error)
 920                 goto out_end_trans;
 921
 922         error = inode_setattr(inode, attr);
 923         gfs2_assert_warn(sdp, !error);
 924
 925         gfs2_trans_add_bh(ip->i_gl, dibh, 1);
 926         gfs2_dinode_out(ip, dibh->b_data);
 927         brelse(dibh);
 928
 929         if (ouid != NO_QUOTA_CHANGE || ogid != NO_QUOTA_CHANGE) {
 930                 gfs2_quota_change(ip, -ip->i_di.di_blocks, ouid, ogid);
 931                 gfs2_quota_change(ip, ip->i_di.di_blocks, nuid, ngid);
 932         }
 933
 934 out_end_trans:
 935         gfs2_trans_end(sdp);
 936 out_gunlock_q:
 937         gfs2_quota_unlock(ip);
 938 out_alloc:
 939         gfs2_alloc_put(ip);
 940         return error;
 941 }
 942
 943 /**
 944  * gfs2_setattr - Change attributes on an inode
 945  * @dentry: The dentry which is changing
 946  * @attr: The structure describing the change
 947  *
 948  * The VFS layer wants to change one or more of an inodes attributes.  Write
 949  * that change out to disk.
 950  *
 951  * Returns: errno
 952  */
 953
 954 static int gfs2_setattr(struct dentry *dentry, struct iattr *attr)
 955 {
 956         struct inode *inode = dentry->d_inode;
 957         struct gfs2_inode *ip = GFS2_I(inode);
 958         struct gfs2_holder i_gh;
 959         int error;
 960
 961         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
 962         if (error)
 963                 return error;
 964
 965         error = -EPERM;
 966         if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
 967                 goto out;
 968
 969         error = inode_change_ok(inode, attr);
 970         if (error)
 971                 goto out;
 972
 973         if (attr->ia_valid & ATTR_SIZE)
 974                 error = setattr_size(inode, attr);
 975         else if (attr->ia_valid & (ATTR_UID | ATTR_GID))
 976                 error = setattr_chown(inode, attr);
 977         else if ((attr->ia_valid & ATTR_MODE) && IS_POSIXACL(inode))
 978                 error = gfs2_acl_chmod(ip, attr);
 979         else
 980                 error = gfs2_setattr_simple(ip, attr);
 981
 982 out:
 983         gfs2_glock_dq_uninit(&i_gh);
 984         if (!error)
 985                 mark_inode_dirty(inode);
 986         return error;
 987 }
 988
 989 /**
 990  * gfs2_getattr - Read out an inode's attributes
 991  * @mnt: The vfsmount the inode is being accessed from
 992  * @dentry: The dentry to stat
 993  * @stat: The inode's stats
 994  *
 995  * This may be called from the VFS directly, or from within GFS2 with the
 996  * inode locked, so we look to see if the glock is already locked and only
 997  * lock the glock if its not already been done. Note that its the NFS
 998  * readdirplus operation which causes this to be called (from filldir)
 999  * with the glock already held.
1000  *
1001  * Returns: errno
1002  */
1003
1004 static int gfs2_getattr(struct vfsmount *mnt, struct dentry *dentry,
1005                         struct kstat *stat)
1006 {
1007         struct inode *inode = dentry->d_inode;
1008         struct gfs2_inode *ip = GFS2_I(inode);
1009         struct gfs2_holder gh;
1010         int error;
1011         int unlock = 0;
1012
1013         if (gfs2_glock_is_locked_by_me(ip->i_gl) == 0) {
1014                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
1015                 if (error)
1016                         return error;
1017                 unlock = 1;
1018         }
1019
1020         generic_fillattr(inode, stat);
1021         if (unlock);
1022                 gfs2_glock_dq_uninit(&gh);
1023
1024         return 0;
1025 }
1026
1027 static int gfs2_setxattr(struct dentry *dentry, const char *name,
1028                          const void *data, size_t size, int flags)
1029 {
1030         struct inode *inode = dentry->d_inode;
1031         struct gfs2_ea_request er;
1032
1033         memset(&er, 0, sizeof(struct gfs2_ea_request));
1034         er.er_type = gfs2_ea_name2type(name, &er.er_name);
1035         if (er.er_type == GFS2_EATYPE_UNUSED)
1036                 return -EOPNOTSUPP;
1037         er.er_data = (char *)data;
1038         er.er_name_len = strlen(er.er_name);
1039         er.er_data_len = size;
1040         er.er_flags = flags;
1041
1042         gfs2_assert_warn(GFS2_SB(inode), !(er.er_flags & GFS2_ERF_MODE));
1043
1044         return gfs2_ea_set(GFS2_I(inode), &er);
1045 }
1046
1047 static ssize_t gfs2_getxattr(struct dentry *dentry, const char *name,
1048                              void *data, size_t size)
1049 {
1050         struct gfs2_ea_request er;
1051
1052         memset(&er, 0, sizeof(struct gfs2_ea_request));
1053         er.er_type = gfs2_ea_name2type(name, &er.er_name);
1054         if (er.er_type == GFS2_EATYPE_UNUSED)
1055                 return -EOPNOTSUPP;
1056         er.er_data = data;
1057         er.er_name_len = strlen(er.er_name);
1058         er.er_data_len = size;
1059
1060         return gfs2_ea_get(GFS2_I(dentry->d_inode), &er);
1061 }
1062
1063 static ssize_t gfs2_listxattr(struct dentry *dentry, char *buffer, size_t size)
1064 {
1065         struct gfs2_ea_request er;
1066
1067         memset(&er, 0, sizeof(struct gfs2_ea_request));
1068         er.er_data = (size) ? buffer : NULL;
1069         er.er_data_len = size;
1070
1071         return gfs2_ea_list(GFS2_I(dentry->d_inode), &er);
1072 }
1073
1074 static int gfs2_removexattr(struct dentry *dentry, const char *name)
1075 {
1076         struct gfs2_ea_request er;
1077
1078         memset(&er, 0, sizeof(struct gfs2_ea_request));
1079         er.er_type = gfs2_ea_name2type(name, &er.er_name);
1080         if (er.er_type == GFS2_EATYPE_UNUSED)
1081                 return -EOPNOTSUPP;
1082         er.er_name_len = strlen(er.er_name);
1083
1084         return gfs2_ea_remove(GFS2_I(dentry->d_inode), &er);
1085 }
1086
1087 struct inode_operations gfs2_file_iops = {
1088         .permission = gfs2_permission,
1089         .setattr = gfs2_setattr,
1090         .getattr = gfs2_getattr,
1091         .setxattr = gfs2_setxattr,
1092         .getxattr = gfs2_getxattr,
1093         .listxattr = gfs2_listxattr,
1094         .removexattr = gfs2_removexattr,
1095 };
1096
1097 struct inode_operations gfs2_dev_iops = {
1098         .permission = gfs2_permission,
1099         .setattr = gfs2_setattr,
1100         .getattr = gfs2_getattr,
1101         .setxattr = gfs2_setxattr,
1102         .getxattr = gfs2_getxattr,
1103         .listxattr = gfs2_listxattr,
1104         .removexattr = gfs2_removexattr,
1105 };
1106
1107 struct inode_operations gfs2_dir_iops = {
1108         .create = gfs2_create,
1109         .lookup = gfs2_lookup,
1110         .link = gfs2_link,
1111         .unlink = gfs2_unlink,
1112         .symlink = gfs2_symlink,
1113         .mkdir = gfs2_mkdir,
1114         .rmdir = gfs2_rmdir,
1115         .mknod = gfs2_mknod,
1116         .rename = gfs2_rename,
1117         .permission = gfs2_permission,
1118         .setattr = gfs2_setattr,
1119         .getattr = gfs2_getattr,
1120         .setxattr = gfs2_setxattr,
1121         .getxattr = gfs2_getxattr,
1122         .listxattr = gfs2_listxattr,
1123         .removexattr = gfs2_removexattr,
1124 };
1125
1126 struct inode_operations gfs2_symlink_iops = {
1127         .readlink = gfs2_readlink,
1128         .follow_link = gfs2_follow_link,
1129         .permission = gfs2_permission,
1130         .setattr = gfs2_setattr,
1131         .getattr = gfs2_getattr,
1132         .setxattr = gfs2_setxattr,
1133         .getxattr = gfs2_getxattr,
1134         .listxattr = gfs2_listxattr,
1135         .removexattr = gfs2_removexattr,
1136 };
1137