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[3];
 268         struct gfs2_rgrpd *rgd;
 269         struct gfs2_holder ri_gh;
 270         int error;
 271
 272         error = gfs2_rindex_hold(sdp, &ri_gh);
 273         if (error)
 274                 return error;
 275
 276         gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
 277         gfs2_holder_init(ip->i_gl,  LM_ST_EXCLUSIVE, 0, ghs + 1);
 278
 279         rgd = gfs2_blk2rgrpd(sdp, ip->i_num.no_addr);
 280         gfs2_holder_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, ghs + 2);
 281
 282
 283         error = gfs2_glock_nq_m(3, ghs);
 284         if (error)
 285                 goto out;
 286
 287         error = gfs2_unlink_ok(dip, &dentry->d_name, ip);
 288         if (error)
 289                 goto out_gunlock;
 290
 291         error = gfs2_trans_begin(sdp, 2*RES_DINODE + RES_LEAF + RES_RG_BIT, 0);
 292         if (error)
 293                 goto out_gunlock;
 294
 295         error = gfs2_dir_del(dip, &dentry->d_name);
 296         if (error)
 297                 goto out_end_trans;
 298
 299         error = gfs2_change_nlink(ip, -1);
 300
 301 out_end_trans:
 302         gfs2_trans_end(sdp);
 303 out_gunlock:
 304         gfs2_glock_dq_m(3, ghs);
 305 out:
 306         gfs2_holder_uninit(ghs);
 307         gfs2_holder_uninit(ghs + 1);
 308         gfs2_holder_uninit(ghs + 2);
 309         gfs2_glock_dq_uninit(&ri_gh);
 310         return error;
 311 }
 312
 313 /**
 314  * gfs2_symlink - Create a symlink
 315  * @dir: The directory to create the symlink in
 316  * @dentry: The dentry to put the symlink in
 317  * @symname: The thing which the link points to
 318  *
 319  * Returns: errno
 320  */
 321
 322 static int gfs2_symlink(struct inode *dir, struct dentry *dentry,
 323                         const char *symname)
 324 {
 325         struct gfs2_inode *dip = GFS2_I(dir), *ip;
 326         struct gfs2_sbd *sdp = GFS2_SB(dir);
 327         struct gfs2_holder ghs[2];
 328         struct inode *inode;
 329         struct buffer_head *dibh;
 330         int size;
 331         int error;
 332
 333         /* Must be stuffed with a null terminator for gfs2_follow_link() */
 334         size = strlen(symname);
 335         if (size > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode) - 1)
 336                 return -ENAMETOOLONG;
 337
 338         gfs2_holder_init(dip->i_gl, 0, 0, ghs);
 339
 340         inode = gfs2_createi(ghs, &dentry->d_name, S_IFLNK | S_IRWXUGO, 0);
 341         if (IS_ERR(inode)) {
 342                 gfs2_holder_uninit(ghs);
 343                 return PTR_ERR(inode);
 344         }
 345
 346         ip = ghs[1].gh_gl->gl_object;
 347
 348         ip->i_di.di_size = size;
 349
 350         error = gfs2_meta_inode_buffer(ip, &dibh);
 351
 352         if (!gfs2_assert_withdraw(sdp, !error)) {
 353                 gfs2_dinode_out(ip, dibh->b_data);
 354                 memcpy(dibh->b_data + sizeof(struct gfs2_dinode), symname,
 355                        size);
 356                 brelse(dibh);
 357         }
 358
 359         gfs2_trans_end(sdp);
 360         if (dip->i_alloc.al_rgd)
 361                 gfs2_inplace_release(dip);
 362         gfs2_quota_unlock(dip);
 363         gfs2_alloc_put(dip);
 364
 365         gfs2_glock_dq_uninit_m(2, ghs);
 366
 367         d_instantiate(dentry, inode);
 368         mark_inode_dirty(inode);
 369
 370         return 0;
 371 }
 372
 373 /**
 374  * gfs2_mkdir - Make a directory
 375  * @dir: The parent directory of the new one
 376  * @dentry: The dentry of the new directory
 377  * @mode: The mode of the new directory
 378  *
 379  * Returns: errno
 380  */
 381
 382 static int gfs2_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 383 {
 384         struct gfs2_inode *dip = GFS2_I(dir), *ip;
 385         struct gfs2_sbd *sdp = GFS2_SB(dir);
 386         struct gfs2_holder ghs[2];
 387         struct inode *inode;
 388         struct buffer_head *dibh;
 389         int error;
 390
 391         gfs2_holder_init(dip->i_gl, 0, 0, ghs);
 392
 393         inode = gfs2_createi(ghs, &dentry->d_name, S_IFDIR | mode, 0);
 394         if (IS_ERR(inode)) {
 395                 gfs2_holder_uninit(ghs);
 396                 return PTR_ERR(inode);
 397         }
 398
 399         ip = ghs[1].gh_gl->gl_object;
 400
 401         ip->i_inode.i_nlink = 2;
 402         ip->i_di.di_size = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode);
 403         ip->i_di.di_flags |= GFS2_DIF_JDATA;
 404         ip->i_di.di_entries = 2;
 405
 406         error = gfs2_meta_inode_buffer(ip, &dibh);
 407
 408         if (!gfs2_assert_withdraw(sdp, !error)) {
 409                 struct gfs2_dinode *di = (struct gfs2_dinode *)dibh->b_data;
 410                 struct gfs2_dirent *dent = (struct gfs2_dirent *)(di+1);
 411                 struct qstr str;
 412
 413                 gfs2_str2qstr(&str, ".");
 414                 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
 415                 gfs2_qstr2dirent(&str, GFS2_DIRENT_SIZE(str.len), dent);
 416                 dent->de_inum = di->di_num; /* already GFS2 endian */
 417                 dent->de_type = cpu_to_be16(DT_DIR);
 418                 di->di_entries = cpu_to_be32(1);
 419
 420                 gfs2_str2qstr(&str, "..");
 421                 dent = (struct gfs2_dirent *)((char*)dent + GFS2_DIRENT_SIZE(1));
 422                 gfs2_qstr2dirent(&str, dibh->b_size - GFS2_DIRENT_SIZE(1) - sizeof(struct gfs2_dinode), dent);
 423
 424                 gfs2_inum_out(&dip->i_num, &dent->de_inum);
 425                 dent->de_type = cpu_to_be16(DT_DIR);
 426
 427                 gfs2_dinode_out(ip, di);
 428
 429                 brelse(dibh);
 430         }
 431
 432         error = gfs2_change_nlink(dip, +1);
 433         gfs2_assert_withdraw(sdp, !error); /* dip already pinned */
 434
 435         gfs2_trans_end(sdp);
 436         if (dip->i_alloc.al_rgd)
 437                 gfs2_inplace_release(dip);
 438         gfs2_quota_unlock(dip);
 439         gfs2_alloc_put(dip);
 440
 441         gfs2_glock_dq_uninit_m(2, ghs);
 442
 443         d_instantiate(dentry, inode);
 444         mark_inode_dirty(inode);
 445
 446         return 0;
 447 }
 448
 449 /**
 450  * gfs2_rmdir - Remove a directory
 451  * @dir: The parent directory of the directory to be removed
 452  * @dentry: The dentry of the directory to remove
 453  *
 454  * Remove a directory. Call gfs2_rmdiri()
 455  *
 456  * Returns: errno
 457  */
 458
 459 static int gfs2_rmdir(struct inode *dir, struct dentry *dentry)
 460 {
 461         struct gfs2_inode *dip = GFS2_I(dir);
 462         struct gfs2_sbd *sdp = GFS2_SB(dir);
 463         struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
 464         struct gfs2_holder ghs[3];
 465         struct gfs2_rgrpd *rgd;
 466         struct gfs2_holder ri_gh;
 467         int error;
 468
 469
 470         error = gfs2_rindex_hold(sdp, &ri_gh);
 471         if (error)
 472                 return error;
 473         gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
 474         gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + 1);
 475
 476         rgd = gfs2_blk2rgrpd(sdp, ip->i_num.no_addr);
 477         gfs2_holder_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, ghs + 2);
 478
 479         error = gfs2_glock_nq_m(3, ghs);
 480         if (error)
 481                 goto out;
 482
 483         error = gfs2_unlink_ok(dip, &dentry->d_name, ip);
 484         if (error)
 485                 goto out_gunlock;
 486
 487         if (ip->i_di.di_entries < 2) {
 488                 if (gfs2_consist_inode(ip))
 489                         gfs2_dinode_print(ip);
 490                 error = -EIO;
 491                 goto out_gunlock;
 492         }
 493         if (ip->i_di.di_entries > 2) {
 494                 error = -ENOTEMPTY;
 495                 goto out_gunlock;
 496         }
 497
 498         error = gfs2_trans_begin(sdp, 2 * RES_DINODE + 3 * RES_LEAF + RES_RG_BIT, 0);
 499         if (error)
 500                 goto out_gunlock;
 501
 502         error = gfs2_rmdiri(dip, &dentry->d_name, ip);
 503
 504         gfs2_trans_end(sdp);
 505
 506 out_gunlock:
 507         gfs2_glock_dq_m(3, ghs);
 508 out:
 509         gfs2_holder_uninit(ghs);
 510         gfs2_holder_uninit(ghs + 1);
 511         gfs2_holder_uninit(ghs + 2);
 512         gfs2_glock_dq_uninit(&ri_gh);
 513         return error;
 514 }
 515
 516 /**
 517  * gfs2_mknod - Make a special file
 518  * @dir: The directory in which the special file will reside
 519  * @dentry: The dentry of the special file
 520  * @mode: The mode of the special file
 521  * @rdev: The device specification of the special file
 522  *
 523  */
 524
 525 static int gfs2_mknod(struct inode *dir, struct dentry *dentry, int mode,
 526                       dev_t dev)
 527 {
 528         struct gfs2_inode *dip = GFS2_I(dir);
 529         struct gfs2_sbd *sdp = GFS2_SB(dir);
 530         struct gfs2_holder ghs[2];
 531         struct inode *inode;
 532
 533         gfs2_holder_init(dip->i_gl, 0, 0, ghs);
 534
 535         inode = gfs2_createi(ghs, &dentry->d_name, mode, dev);
 536         if (IS_ERR(inode)) {
 537                 gfs2_holder_uninit(ghs);
 538                 return PTR_ERR(inode);
 539         }
 540
 541         gfs2_trans_end(sdp);
 542         if (dip->i_alloc.al_rgd)
 543                 gfs2_inplace_release(dip);
 544         gfs2_quota_unlock(dip);
 545         gfs2_alloc_put(dip);
 546
 547         gfs2_glock_dq_uninit_m(2, ghs);
 548
 549         d_instantiate(dentry, inode);
 550         mark_inode_dirty(inode);
 551
 552         return 0;
 553 }
 554
 555 /**
 556  * gfs2_rename - Rename a file
 557  * @odir: Parent directory of old file name
 558  * @odentry: The old dentry of the file
 559  * @ndir: Parent directory of new file name
 560  * @ndentry: The new dentry of the file
 561  *
 562  * Returns: errno
 563  */
 564
 565 static int gfs2_rename(struct inode *odir, struct dentry *odentry,
 566                        struct inode *ndir, struct dentry *ndentry)
 567 {
 568         struct gfs2_inode *odip = GFS2_I(odir);
 569         struct gfs2_inode *ndip = GFS2_I(ndir);
 570         struct gfs2_inode *ip = GFS2_I(odentry->d_inode);
 571         struct gfs2_inode *nip = NULL;
 572         struct gfs2_sbd *sdp = GFS2_SB(odir);
 573         struct gfs2_holder ghs[5], r_gh;
 574         struct gfs2_rgrpd *nrgd;
 575         unsigned int num_gh;
 576         int dir_rename = 0;
 577         int alloc_required;
 578         unsigned int x;
 579         int error;
 580
 581         if (ndentry->d_inode) {
 582                 nip = GFS2_I(ndentry->d_inode);
 583                 if (ip == nip)
 584                         return 0;
 585         }
 586
 587         /* Make sure we aren't trying to move a dirctory into it's subdir */
 588
 589         if (S_ISDIR(ip->i_inode.i_mode) && odip != ndip) {
 590                 dir_rename = 1;
 591
 592                 error = gfs2_glock_nq_init(sdp->sd_rename_gl, LM_ST_EXCLUSIVE, 0,
 593                                            &r_gh);
 594                 if (error)
 595                         goto out;
 596
 597                 error = gfs2_ok_to_move(ip, ndip);
 598                 if (error)
 599                         goto out_gunlock_r;
 600         }
 601
 602         num_gh = 1;
 603         gfs2_holder_init(odip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
 604         if (odip != ndip) {
 605                 gfs2_holder_init(ndip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
 606                 num_gh++;
 607         }
 608         gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
 609         num_gh++;
 610
 611         if (nip) {
 612                 gfs2_holder_init(nip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
 613                 num_gh++;
 614                 /* grab the resource lock for unlink flag twiddling
 615                  * this is the case of the target file already existing
 616                  * so we unlink before doing the rename
 617                  */
 618                 nrgd = gfs2_blk2rgrpd(sdp, nip->i_num.no_addr);
 619                 if (nrgd)
 620                         gfs2_holder_init(nrgd->rd_gl, LM_ST_EXCLUSIVE, 0, ghs + 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_inode.i_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_inode.i_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_inode.i_mode) &&
 678                             ndip->i_inode.i_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_inode.i_uid, ndip->i_inode.i_gid);
 706                 if (error)
 707                         goto out_gunlock_q;
 708
 709                 al->al_requested = sdp->sd_max_dirres;
 710
 711                 error = gfs2_inplace_reserve(ndip);
 712                 if (error)
 713                         goto out_gunlock_q;
 714
 715                 error = gfs2_trans_begin(sdp, sdp->sd_max_dirres +
 716                                          al->al_rgd->rd_ri.ri_length +
 717                                          4 * RES_DINODE + 4 * RES_LEAF +
 718                                          RES_STATFS + RES_QUOTA + 4, 0);
 719                 if (error)
 720                         goto out_ipreserv;
 721         } else {
 722                 error = gfs2_trans_begin(sdp, 4 * RES_DINODE +
 723                                          5 * RES_LEAF + 4, 0);
 724                 if (error)
 725                         goto out_gunlock;
 726         }
 727
 728         /* Remove the target file, if it exists */
 729
 730         if (nip) {
 731                 if (S_ISDIR(nip->i_inode.i_mode))
 732                         error = gfs2_rmdiri(ndip, &ndentry->d_name, nip);
 733                 else {
 734                         error = gfs2_dir_del(ndip, &ndentry->d_name);
 735                         if (error)
 736                                 goto out_end_trans;
 737                         error = gfs2_change_nlink(nip, -1);
 738                 }
 739                 if (error)
 740                         goto out_end_trans;
 741         }
 742
 743         if (dir_rename) {
 744                 struct qstr name;
 745                 gfs2_str2qstr(&name, "..");
 746
 747                 error = gfs2_change_nlink(ndip, +1);
 748                 if (error)
 749                         goto out_end_trans;
 750                 error = gfs2_change_nlink(odip, -1);
 751                 if (error)
 752                         goto out_end_trans;
 753
 754                 error = gfs2_dir_mvino(ip, &name, &ndip->i_num, DT_DIR);
 755                 if (error)
 756                         goto out_end_trans;
 757         } else {
 758                 struct buffer_head *dibh;
 759                 error = gfs2_meta_inode_buffer(ip, &dibh);
 760                 if (error)
 761                         goto out_end_trans;
 762                 ip->i_inode.i_ctime = CURRENT_TIME_SEC;
 763                 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
 764                 gfs2_dinode_out(ip, dibh->b_data);
 765                 brelse(dibh);
 766         }
 767
 768         error = gfs2_dir_del(odip, &odentry->d_name);
 769         if (error)
 770                 goto out_end_trans;
 771
 772         error = gfs2_dir_add(ndir, &ndentry->d_name, &ip->i_num,
 773                              IF2DT(ip->i_inode.i_mode));
 774         if (error)
 775                 goto out_end_trans;
 776
 777 out_end_trans:
 778         gfs2_trans_end(sdp);
 779 out_ipreserv:
 780         if (alloc_required)
 781                 gfs2_inplace_release(ndip);
 782 out_gunlock_q:
 783         if (alloc_required)
 784                 gfs2_quota_unlock(ndip);
 785 out_alloc:
 786         if (alloc_required)
 787                 gfs2_alloc_put(ndip);
 788 out_gunlock:
 789         gfs2_glock_dq_m(num_gh, ghs);
 790 out_uninit:
 791         for (x = 0; x < num_gh; x++)
 792                 gfs2_holder_uninit(ghs + x);
 793 out_gunlock_r:
 794         if (dir_rename)
 795                 gfs2_glock_dq_uninit(&r_gh);
 796 out:
 797         return error;
 798 }
 799
 800 /**
 801  * gfs2_readlink - Read the value of a symlink
 802  * @dentry: the symlink
 803  * @buf: the buffer to read the symlink data into
 804  * @size: the size of the buffer
 805  *
 806  * Returns: errno
 807  */
 808
 809 static int gfs2_readlink(struct dentry *dentry, char __user *user_buf,
 810                          int user_size)
 811 {
 812         struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
 813         char array[GFS2_FAST_NAME_SIZE], *buf = array;
 814         unsigned int len = GFS2_FAST_NAME_SIZE;
 815         int error;
 816
 817         error = gfs2_readlinki(ip, &buf, &len);
 818         if (error)
 819                 return error;
 820
 821         if (user_size > len - 1)
 822                 user_size = len - 1;
 823
 824         if (copy_to_user(user_buf, buf, user_size))
 825                 error = -EFAULT;
 826         else
 827                 error = user_size;
 828
 829         if (buf != array)
 830                 kfree(buf);
 831
 832         return error;
 833 }
 834
 835 /**
 836  * gfs2_follow_link - Follow a symbolic link
 837  * @dentry: The dentry of the link
 838  * @nd: Data that we pass to vfs_follow_link()
 839  *
 840  * This can handle symlinks of any size. It is optimised for symlinks
 841  * under GFS2_FAST_NAME_SIZE.
 842  *
 843  * Returns: 0 on success or error code
 844  */
 845
 846 static void *gfs2_follow_link(struct dentry *dentry, struct nameidata *nd)
 847 {
 848         struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
 849         char array[GFS2_FAST_NAME_SIZE], *buf = array;
 850         unsigned int len = GFS2_FAST_NAME_SIZE;
 851         int error;
 852
 853         error = gfs2_readlinki(ip, &buf, &len);
 854         if (!error) {
 855                 error = vfs_follow_link(nd, buf);
 856                 if (buf != array)
 857                         kfree(buf);
 858         }
 859
 860         return ERR_PTR(error);
 861 }
 862
 863 /**
 864  * gfs2_permission -
 865  * @inode:
 866  * @mask:
 867  * @nd: passed from Linux VFS, ignored by us
 868  *
 869  * This may be called from the VFS directly, or from within GFS2 with the
 870  * inode locked, so we look to see if the glock is already locked and only
 871  * lock the glock if its not already been done.
 872  *
 873  * Returns: errno
 874  */
 875
 876 static int gfs2_permission(struct inode *inode, int mask, struct nameidata *nd)
 877 {
 878         struct gfs2_inode *ip = GFS2_I(inode);
 879         struct gfs2_holder i_gh;
 880         int error;
 881         int unlock = 0;
 882
 883         if (gfs2_glock_is_locked_by_me(ip->i_gl) == 0) {
 884                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
 885                 if (error)
 886                         return error;
 887                 unlock = 1;
 888         }
 889
 890         error = generic_permission(inode, mask, gfs2_check_acl);
 891         if (unlock)
 892                 gfs2_glock_dq_uninit(&i_gh);
 893
 894         return error;
 895 }
 896
 897 static int setattr_size(struct inode *inode, struct iattr *attr)
 898 {
 899         struct gfs2_inode *ip = GFS2_I(inode);
 900         int error;
 901
 902         if (attr->ia_size != ip->i_di.di_size) {
 903                 error = vmtruncate(inode, attr->ia_size);
 904                 if (error)
 905                         return error;
 906         }
 907
 908         error = gfs2_truncatei(ip, attr->ia_size);
 909         if (error)
 910                 return error;
 911
 912         return error;
 913 }
 914
 915 static int setattr_chown(struct inode *inode, struct iattr *attr)
 916 {
 917         struct gfs2_inode *ip = GFS2_I(inode);
 918         struct gfs2_sbd *sdp = GFS2_SB(inode);
 919         struct buffer_head *dibh;
 920         u32 ouid, ogid, nuid, ngid;
 921         int error;
 922
 923         ouid = inode->i_uid;
 924         ogid = inode->i_gid;
 925         nuid = attr->ia_uid;
 926         ngid = attr->ia_gid;
 927
 928         if (!(attr->ia_valid & ATTR_UID) || ouid == nuid)
 929                 ouid = nuid = NO_QUOTA_CHANGE;
 930         if (!(attr->ia_valid & ATTR_GID) || ogid == ngid)
 931                 ogid = ngid = NO_QUOTA_CHANGE;
 932
 933         gfs2_alloc_get(ip);
 934
 935         error = gfs2_quota_lock(ip, nuid, ngid);
 936         if (error)
 937                 goto out_alloc;
 938
 939         if (ouid != NO_QUOTA_CHANGE || ogid != NO_QUOTA_CHANGE) {
 940                 error = gfs2_quota_check(ip, nuid, ngid);
 941                 if (error)
 942                         goto out_gunlock_q;
 943         }
 944
 945         error = gfs2_trans_begin(sdp, RES_DINODE + 2 * RES_QUOTA, 0);
 946         if (error)
 947                 goto out_gunlock_q;
 948
 949         error = gfs2_meta_inode_buffer(ip, &dibh);
 950         if (error)
 951                 goto out_end_trans;
 952
 953         error = inode_setattr(inode, attr);
 954         gfs2_assert_warn(sdp, !error);
 955
 956         gfs2_trans_add_bh(ip->i_gl, dibh, 1);
 957         gfs2_dinode_out(ip, dibh->b_data);
 958         brelse(dibh);
 959
 960         if (ouid != NO_QUOTA_CHANGE || ogid != NO_QUOTA_CHANGE) {
 961                 gfs2_quota_change(ip, -ip->i_di.di_blocks, ouid, ogid);
 962                 gfs2_quota_change(ip, ip->i_di.di_blocks, nuid, ngid);
 963         }
 964
 965 out_end_trans:
 966         gfs2_trans_end(sdp);
 967 out_gunlock_q:
 968         gfs2_quota_unlock(ip);
 969 out_alloc:
 970         gfs2_alloc_put(ip);
 971         return error;
 972 }
 973
 974 /**
 975  * gfs2_setattr - Change attributes on an inode
 976  * @dentry: The dentry which is changing
 977  * @attr: The structure describing the change
 978  *
 979  * The VFS layer wants to change one or more of an inodes attributes.  Write
 980  * that change out to disk.
 981  *
 982  * Returns: errno
 983  */
 984
 985 static int gfs2_setattr(struct dentry *dentry, struct iattr *attr)
 986 {
 987         struct inode *inode = dentry->d_inode;
 988         struct gfs2_inode *ip = GFS2_I(inode);
 989         struct gfs2_holder i_gh;
 990         int error;
 991
 992         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
 993         if (error)
 994                 return error;
 995
 996         error = -EPERM;
 997         if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
 998                 goto out;
 999
1000         error = inode_change_ok(inode, attr);
1001         if (error)
1002                 goto out;
1003
1004         if (attr->ia_valid & ATTR_SIZE)
1005                 error = setattr_size(inode, attr);
1006         else if (attr->ia_valid & (ATTR_UID | ATTR_GID))
1007                 error = setattr_chown(inode, attr);
1008         else if ((attr->ia_valid & ATTR_MODE) && IS_POSIXACL(inode))
1009                 error = gfs2_acl_chmod(ip, attr);
1010         else
1011                 error = gfs2_setattr_simple(ip, attr);
1012
1013 out:
1014         gfs2_glock_dq_uninit(&i_gh);
1015         if (!error)
1016                 mark_inode_dirty(inode);
1017         return error;
1018 }
1019
1020 /**
1021  * gfs2_getattr - Read out an inode's attributes
1022  * @mnt: The vfsmount the inode is being accessed from
1023  * @dentry: The dentry to stat
1024  * @stat: The inode's stats
1025  *
1026  * This may be called from the VFS directly, or from within GFS2 with the
1027  * inode locked, so we look to see if the glock is already locked and only
1028  * lock the glock if its not already been done. Note that its the NFS
1029  * readdirplus operation which causes this to be called (from filldir)
1030  * with the glock already held.
1031  *
1032  * Returns: errno
1033  */
1034
1035 static int gfs2_getattr(struct vfsmount *mnt, struct dentry *dentry,
1036                         struct kstat *stat)
1037 {
1038         struct inode *inode = dentry->d_inode;
1039         struct gfs2_inode *ip = GFS2_I(inode);
1040         struct gfs2_holder gh;
1041         int error;
1042         int unlock = 0;
1043
1044         if (gfs2_glock_is_locked_by_me(ip->i_gl) == 0) {
1045                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
1046                 if (error)
1047                         return error;
1048                 unlock = 1;
1049         }
1050
1051         generic_fillattr(inode, stat);
1052         if (unlock)
1053                 gfs2_glock_dq_uninit(&gh);
1054
1055         return 0;
1056 }
1057
1058 static int gfs2_setxattr(struct dentry *dentry, const char *name,
1059                          const void *data, size_t size, int flags)
1060 {
1061         struct inode *inode = dentry->d_inode;
1062         struct gfs2_ea_request er;
1063
1064         memset(&er, 0, sizeof(struct gfs2_ea_request));
1065         er.er_type = gfs2_ea_name2type(name, &er.er_name);
1066         if (er.er_type == GFS2_EATYPE_UNUSED)
1067                 return -EOPNOTSUPP;
1068         er.er_data = (char *)data;
1069         er.er_name_len = strlen(er.er_name);
1070         er.er_data_len = size;
1071         er.er_flags = flags;
1072
1073         gfs2_assert_warn(GFS2_SB(inode), !(er.er_flags & GFS2_ERF_MODE));
1074
1075         return gfs2_ea_set(GFS2_I(inode), &er);
1076 }
1077
1078 static ssize_t gfs2_getxattr(struct dentry *dentry, const char *name,
1079                              void *data, size_t size)
1080 {
1081         struct gfs2_ea_request er;
1082
1083         memset(&er, 0, sizeof(struct gfs2_ea_request));
1084         er.er_type = gfs2_ea_name2type(name, &er.er_name);
1085         if (er.er_type == GFS2_EATYPE_UNUSED)
1086                 return -EOPNOTSUPP;
1087         er.er_data = data;
1088         er.er_name_len = strlen(er.er_name);
1089         er.er_data_len = size;
1090
1091         return gfs2_ea_get(GFS2_I(dentry->d_inode), &er);
1092 }
1093
1094 static ssize_t gfs2_listxattr(struct dentry *dentry, char *buffer, size_t size)
1095 {
1096         struct gfs2_ea_request er;
1097
1098         memset(&er, 0, sizeof(struct gfs2_ea_request));
1099         er.er_data = (size) ? buffer : NULL;
1100         er.er_data_len = size;
1101
1102         return gfs2_ea_list(GFS2_I(dentry->d_inode), &er);
1103 }
1104
1105 static int gfs2_removexattr(struct dentry *dentry, const char *name)
1106 {
1107         struct gfs2_ea_request er;
1108
1109         memset(&er, 0, sizeof(struct gfs2_ea_request));
1110         er.er_type = gfs2_ea_name2type(name, &er.er_name);
1111         if (er.er_type == GFS2_EATYPE_UNUSED)
1112                 return -EOPNOTSUPP;
1113         er.er_name_len = strlen(er.er_name);
1114
1115         return gfs2_ea_remove(GFS2_I(dentry->d_inode), &er);
1116 }
1117
1118 struct inode_operations gfs2_file_iops = {
1119         .permission = gfs2_permission,
1120         .setattr = gfs2_setattr,
1121         .getattr = gfs2_getattr,
1122         .setxattr = gfs2_setxattr,
1123         .getxattr = gfs2_getxattr,
1124         .listxattr = gfs2_listxattr,
1125         .removexattr = gfs2_removexattr,
1126 };
1127
1128 struct inode_operations gfs2_dev_iops = {
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
1138 struct inode_operations gfs2_dir_iops = {
1139         .create = gfs2_create,
1140         .lookup = gfs2_lookup,
1141         .link = gfs2_link,
1142         .unlink = gfs2_unlink,
1143         .symlink = gfs2_symlink,
1144         .mkdir = gfs2_mkdir,
1145         .rmdir = gfs2_rmdir,
1146         .mknod = gfs2_mknod,
1147         .rename = gfs2_rename,
1148         .permission = gfs2_permission,
1149         .setattr = gfs2_setattr,
1150         .getattr = gfs2_getattr,
1151         .setxattr = gfs2_setxattr,
1152         .getxattr = gfs2_getxattr,
1153         .listxattr = gfs2_listxattr,
1154         .removexattr = gfs2_removexattr,
1155 };
1156
1157 struct inode_operations gfs2_symlink_iops = {
1158         .readlink = gfs2_readlink,
1159         .follow_link = gfs2_follow_link,
1160         .permission = gfs2_permission,
1161         .setattr = gfs2_setattr,
1162         .getattr = gfs2_getattr,
1163         .setxattr = gfs2_setxattr,
1164         .getxattr = gfs2_getxattr,
1165         .listxattr = gfs2_listxattr,
1166         .removexattr = gfs2_removexattr,
1167 };
1168