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/slab.h>
  11 #include <linux/spinlock.h>
  12 #include <linux/completion.h>
  13 #include <linux/buffer_head.h>
  14 #include <linux/namei.h>
  15 #include <linux/utsname.h>
  16 #include <linux/mm.h>
  17 #include <linux/xattr.h>
  18 #include <linux/posix_acl.h>
  19 #include <linux/gfs2_ondisk.h>
  20 #include <linux/crc32.h>
  21 #include <linux/lm_interface.h>
  22 #include <asm/uaccess.h>
  23
  24 #include "gfs2.h"
  25 #include "incore.h"
  26 #include "acl.h"
  27 #include "bmap.h"
  28 #include "dir.h"
  29 #include "eaops.h"
  30 #include "eattr.h"
  31 #include "glock.h"
  32 #include "inode.h"
  33 #include "meta_io.h"
  34 #include "ops_dentry.h"
  35 #include "ops_inode.h"
  36 #include "quota.h"
  37 #include "rgrp.h"
  38 #include "trans.h"
  39 #include "util.h"
  40
  41 /**
  42  * gfs2_create - Create a file
  43  * @dir: The directory in which to create the file
  44  * @dentry: The dentry of the new file
  45  * @mode: The mode of the new file
  46  *
  47  * Returns: errno
  48  */
  49
  50 static int gfs2_create(struct inode *dir, struct dentry *dentry,
  51                        int mode, struct nameidata *nd)
  52 {
  53         struct gfs2_inode *dip = GFS2_I(dir);
  54         struct gfs2_sbd *sdp = GFS2_SB(dir);
  55         struct gfs2_holder ghs[2];
  56         struct inode *inode;
  57
  58         gfs2_holder_init(dip->i_gl, 0, 0, ghs);
  59
  60         for (;;) {
  61                 inode = gfs2_createi(ghs, &dentry->d_name, S_IFREG | mode, 0);
  62                 if (!IS_ERR(inode)) {
  63                         gfs2_trans_end(sdp);
  64                         if (dip->i_alloc->al_rgd)
  65                                 gfs2_inplace_release(dip);
  66                         gfs2_quota_unlock(dip);
  67                         gfs2_alloc_put(dip);
  68                         gfs2_glock_dq_uninit_m(2, ghs);
  69                         mark_inode_dirty(inode);
  70                         break;
  71                 } else if (PTR_ERR(inode) != -EEXIST ||
  72                            (nd && (nd->intent.open.flags & O_EXCL))) {
  73                         gfs2_holder_uninit(ghs);
  74                         return PTR_ERR(inode);
  75                 }
  76
  77                 inode = gfs2_lookupi(dir, &dentry->d_name, 0);
  78                 if (inode) {
  79                         if (!IS_ERR(inode)) {
  80                                 gfs2_holder_uninit(ghs);
  81                                 break;
  82                         } else {
  83                                 gfs2_holder_uninit(ghs);
  84                                 return PTR_ERR(inode);
  85                         }
  86                 }
  87         }
  88
  89         d_instantiate(dentry, inode);
  90
  91         return 0;
  92 }
  93
  94 /**
  95  * gfs2_lookup - Look up a filename in a directory and return its inode
  96  * @dir: The directory inode
  97  * @dentry: The dentry of the new inode
  98  * @nd: passed from Linux VFS, ignored by us
  99  *
 100  * Called by the VFS layer. Lock dir and call gfs2_lookupi()
 101  *
 102  * Returns: errno
 103  */
 104
 105 static struct dentry *gfs2_lookup(struct inode *dir, struct dentry *dentry,
 106                                   struct nameidata *nd)
 107 {
 108         struct inode *inode = NULL;
 109
 110         dentry->d_op = &gfs2_dops;
 111
 112         inode = gfs2_lookupi(dir, &dentry->d_name, 0);
 113         if (inode && IS_ERR(inode))
 114                 return ERR_CAST(inode);
 115
 116         if (inode) {
 117                 struct gfs2_glock *gl = GFS2_I(inode)->i_gl;
 118                 struct gfs2_holder gh;
 119                 int error;
 120                 error = gfs2_glock_nq_init(gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
 121                 if (error) {
 122                         iput(inode);
 123                         return ERR_PTR(error);
 124                 }
 125                 gfs2_glock_dq_uninit(&gh);
 126                 return d_splice_alias(inode, dentry);
 127         }
 128         d_add(dentry, inode);
 129
 130         return NULL;
 131 }
 132
 133 /**
 134  * gfs2_link - Link to a file
 135  * @old_dentry: The inode to link
 136  * @dir: Add link to this directory
 137  * @dentry: The name of the link
 138  *
 139  * Link the inode in "old_dentry" into the directory "dir" with the
 140  * name in "dentry".
 141  *
 142  * Returns: errno
 143  */
 144
 145 static int gfs2_link(struct dentry *old_dentry, struct inode *dir,
 146                      struct dentry *dentry)
 147 {
 148         struct gfs2_inode *dip = GFS2_I(dir);
 149         struct gfs2_sbd *sdp = GFS2_SB(dir);
 150         struct inode *inode = old_dentry->d_inode;
 151         struct gfs2_inode *ip = GFS2_I(inode);
 152         struct gfs2_holder ghs[2];
 153         int alloc_required;
 154         int error;
 155
 156         if (S_ISDIR(inode->i_mode))
 157                 return -EPERM;
 158
 159         gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
 160         gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + 1);
 161
 162         error = gfs2_glock_nq(ghs); /* parent */
 163         if (error)
 164                 goto out_parent;
 165
 166         error = gfs2_glock_nq(ghs + 1); /* child */
 167         if (error)
 168                 goto out_child;
 169
 170         error = gfs2_permission(dir, MAY_WRITE | MAY_EXEC);
 171         if (error)
 172                 goto out_gunlock;
 173
 174         error = gfs2_dir_check(dir, &dentry->d_name, NULL);
 175         switch (error) {
 176         case -ENOENT:
 177                 break;
 178         case 0:
 179                 error = -EEXIST;
 180         default:
 181                 goto out_gunlock;
 182         }
 183
 184         error = -EINVAL;
 185         if (!dip->i_inode.i_nlink)
 186                 goto out_gunlock;
 187         error = -EFBIG;
 188         if (dip->i_di.di_entries == (u32)-1)
 189                 goto out_gunlock;
 190         error = -EPERM;
 191         if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
 192                 goto out_gunlock;
 193         error = -EINVAL;
 194         if (!ip->i_inode.i_nlink)
 195                 goto out_gunlock;
 196         error = -EMLINK;
 197         if (ip->i_inode.i_nlink == (u32)-1)
 198                 goto out_gunlock;
 199
 200         alloc_required = error = gfs2_diradd_alloc_required(dir, &dentry->d_name);
 201         if (error < 0)
 202                 goto out_gunlock;
 203         error = 0;
 204
 205         if (alloc_required) {
 206                 struct gfs2_alloc *al = gfs2_alloc_get(dip);
 207                 if (!al) {
 208                         error = -ENOMEM;
 209                         goto out_gunlock;
 210                 }
 211
 212                 error = gfs2_quota_lock_check(dip);
 213                 if (error)
 214                         goto out_alloc;
 215
 216                 al->al_requested = sdp->sd_max_dirres;
 217
 218                 error = gfs2_inplace_reserve(dip);
 219                 if (error)
 220                         goto out_gunlock_q;
 221
 222                 error = gfs2_trans_begin(sdp, sdp->sd_max_dirres +
 223                                          al->al_rgd->rd_length +
 224                                          2 * RES_DINODE + RES_STATFS +
 225                                          RES_QUOTA, 0);
 226                 if (error)
 227                         goto out_ipres;
 228         } else {
 229                 error = gfs2_trans_begin(sdp, 2 * RES_DINODE + RES_LEAF, 0);
 230                 if (error)
 231                         goto out_ipres;
 232         }
 233
 234         error = gfs2_dir_add(dir, &dentry->d_name, ip, IF2DT(inode->i_mode));
 235         if (error)
 236                 goto out_end_trans;
 237
 238         error = gfs2_change_nlink(ip, +1);
 239
 240 out_end_trans:
 241         gfs2_trans_end(sdp);
 242 out_ipres:
 243         if (alloc_required)
 244                 gfs2_inplace_release(dip);
 245 out_gunlock_q:
 246         if (alloc_required)
 247                 gfs2_quota_unlock(dip);
 248 out_alloc:
 249         if (alloc_required)
 250                 gfs2_alloc_put(dip);
 251 out_gunlock:
 252         gfs2_glock_dq(ghs + 1);
 253 out_child:
 254         gfs2_glock_dq(ghs);
 255 out_parent:
 256         gfs2_holder_uninit(ghs);
 257         gfs2_holder_uninit(ghs + 1);
 258         if (!error) {
 259                 atomic_inc(&inode->i_count);
 260                 d_instantiate(dentry, inode);
 261                 mark_inode_dirty(inode);
 262         }
 263         return error;
 264 }
 265
 266 /**
 267  * gfs2_unlink - Unlink a file
 268  * @dir: The inode of the directory containing the file to unlink
 269  * @dentry: The file itself
 270  *
 271  * Unlink a file.  Call gfs2_unlinki()
 272  *
 273  * Returns: errno
 274  */
 275
 276 static int gfs2_unlink(struct inode *dir, struct dentry *dentry)
 277 {
 278         struct gfs2_inode *dip = GFS2_I(dir);
 279         struct gfs2_sbd *sdp = GFS2_SB(dir);
 280         struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
 281         struct gfs2_holder ghs[3];
 282         struct gfs2_rgrpd *rgd;
 283         struct gfs2_holder ri_gh;
 284         int error;
 285
 286         error = gfs2_rindex_hold(sdp, &ri_gh);
 287         if (error)
 288                 return error;
 289
 290         gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
 291         gfs2_holder_init(ip->i_gl,  LM_ST_EXCLUSIVE, 0, ghs + 1);
 292
 293         rgd = gfs2_blk2rgrpd(sdp, ip->i_no_addr);
 294         gfs2_holder_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, ghs + 2);
 295
 296
 297         error = gfs2_glock_nq(ghs); /* parent */
 298         if (error)
 299                 goto out_parent;
 300
 301         error = gfs2_glock_nq(ghs + 1); /* child */
 302         if (error)
 303                 goto out_child;
 304
 305         error = gfs2_glock_nq(ghs + 2); /* rgrp */
 306         if (error)
 307                 goto out_rgrp;
 308
 309         error = gfs2_unlink_ok(dip, &dentry->d_name, ip);
 310         if (error)
 311                 goto out_gunlock;
 312
 313         error = gfs2_trans_begin(sdp, 2*RES_DINODE + RES_LEAF + RES_RG_BIT, 0);
 314         if (error)
 315                 goto out_rgrp;
 316
 317         error = gfs2_dir_del(dip, &dentry->d_name);
 318         if (error)
 319                 goto out_end_trans;
 320
 321         error = gfs2_change_nlink(ip, -1);
 322
 323 out_end_trans:
 324         gfs2_trans_end(sdp);
 325 out_gunlock:
 326         gfs2_glock_dq(ghs + 2);
 327 out_rgrp:
 328         gfs2_holder_uninit(ghs + 2);
 329         gfs2_glock_dq(ghs + 1);
 330 out_child:
 331         gfs2_holder_uninit(ghs + 1);
 332         gfs2_glock_dq(ghs);
 333 out_parent:
 334         gfs2_holder_uninit(ghs);
 335         gfs2_glock_dq_uninit(&ri_gh);
 336         return error;
 337 }
 338
 339 /**
 340  * gfs2_symlink - Create a symlink
 341  * @dir: The directory to create the symlink in
 342  * @dentry: The dentry to put the symlink in
 343  * @symname: The thing which the link points to
 344  *
 345  * Returns: errno
 346  */
 347
 348 static int gfs2_symlink(struct inode *dir, struct dentry *dentry,
 349                         const char *symname)
 350 {
 351         struct gfs2_inode *dip = GFS2_I(dir), *ip;
 352         struct gfs2_sbd *sdp = GFS2_SB(dir);
 353         struct gfs2_holder ghs[2];
 354         struct inode *inode;
 355         struct buffer_head *dibh;
 356         int size;
 357         int error;
 358
 359         /* Must be stuffed with a null terminator for gfs2_follow_link() */
 360         size = strlen(symname);
 361         if (size > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode) - 1)
 362                 return -ENAMETOOLONG;
 363
 364         gfs2_holder_init(dip->i_gl, 0, 0, ghs);
 365
 366         inode = gfs2_createi(ghs, &dentry->d_name, S_IFLNK | S_IRWXUGO, 0);
 367         if (IS_ERR(inode)) {
 368                 gfs2_holder_uninit(ghs);
 369                 return PTR_ERR(inode);
 370         }
 371
 372         ip = ghs[1].gh_gl->gl_object;
 373
 374         ip->i_di.di_size = size;
 375
 376         error = gfs2_meta_inode_buffer(ip, &dibh);
 377
 378         if (!gfs2_assert_withdraw(sdp, !error)) {
 379                 gfs2_dinode_out(ip, dibh->b_data);
 380                 memcpy(dibh->b_data + sizeof(struct gfs2_dinode), symname,
 381                        size);
 382                 brelse(dibh);
 383         }
 384
 385         gfs2_trans_end(sdp);
 386         if (dip->i_alloc->al_rgd)
 387                 gfs2_inplace_release(dip);
 388         gfs2_quota_unlock(dip);
 389         gfs2_alloc_put(dip);
 390
 391         gfs2_glock_dq_uninit_m(2, ghs);
 392
 393         d_instantiate(dentry, inode);
 394         mark_inode_dirty(inode);
 395
 396         return 0;
 397 }
 398
 399 /**
 400  * gfs2_mkdir - Make a directory
 401  * @dir: The parent directory of the new one
 402  * @dentry: The dentry of the new directory
 403  * @mode: The mode of the new directory
 404  *
 405  * Returns: errno
 406  */
 407
 408 static int gfs2_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 409 {
 410         struct gfs2_inode *dip = GFS2_I(dir), *ip;
 411         struct gfs2_sbd *sdp = GFS2_SB(dir);
 412         struct gfs2_holder ghs[2];
 413         struct inode *inode;
 414         struct buffer_head *dibh;
 415         int error;
 416
 417         gfs2_holder_init(dip->i_gl, 0, 0, ghs);
 418
 419         inode = gfs2_createi(ghs, &dentry->d_name, S_IFDIR | mode, 0);
 420         if (IS_ERR(inode)) {
 421                 gfs2_holder_uninit(ghs);
 422                 return PTR_ERR(inode);
 423         }
 424
 425         ip = ghs[1].gh_gl->gl_object;
 426
 427         ip->i_inode.i_nlink = 2;
 428         ip->i_di.di_size = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode);
 429         ip->i_di.di_flags |= GFS2_DIF_JDATA;
 430         ip->i_di.di_entries = 2;
 431
 432         error = gfs2_meta_inode_buffer(ip, &dibh);
 433
 434         if (!gfs2_assert_withdraw(sdp, !error)) {
 435                 struct gfs2_dinode *di = (struct gfs2_dinode *)dibh->b_data;
 436                 struct gfs2_dirent *dent = (struct gfs2_dirent *)(di+1);
 437                 struct qstr str;
 438
 439                 gfs2_str2qstr(&str, ".");
 440                 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
 441                 gfs2_qstr2dirent(&str, GFS2_DIRENT_SIZE(str.len), dent);
 442                 dent->de_inum = di->di_num; /* already GFS2 endian */
 443                 dent->de_type = cpu_to_be16(DT_DIR);
 444                 di->di_entries = cpu_to_be32(1);
 445
 446                 gfs2_str2qstr(&str, "..");
 447                 dent = (struct gfs2_dirent *)((char*)dent + GFS2_DIRENT_SIZE(1));
 448                 gfs2_qstr2dirent(&str, dibh->b_size - GFS2_DIRENT_SIZE(1) - sizeof(struct gfs2_dinode), dent);
 449
 450                 gfs2_inum_out(dip, dent);
 451                 dent->de_type = cpu_to_be16(DT_DIR);
 452
 453                 gfs2_dinode_out(ip, di);
 454
 455                 brelse(dibh);
 456         }
 457
 458         error = gfs2_change_nlink(dip, +1);
 459         gfs2_assert_withdraw(sdp, !error); /* dip already pinned */
 460
 461         gfs2_trans_end(sdp);
 462         if (dip->i_alloc->al_rgd)
 463                 gfs2_inplace_release(dip);
 464         gfs2_quota_unlock(dip);
 465         gfs2_alloc_put(dip);
 466
 467         gfs2_glock_dq_uninit_m(2, ghs);
 468
 469         d_instantiate(dentry, inode);
 470         mark_inode_dirty(inode);
 471
 472         return 0;
 473 }
 474
 475 /**
 476  * gfs2_rmdir - Remove a directory
 477  * @dir: The parent directory of the directory to be removed
 478  * @dentry: The dentry of the directory to remove
 479  *
 480  * Remove a directory. Call gfs2_rmdiri()
 481  *
 482  * Returns: errno
 483  */
 484
 485 static int gfs2_rmdir(struct inode *dir, struct dentry *dentry)
 486 {
 487         struct gfs2_inode *dip = GFS2_I(dir);
 488         struct gfs2_sbd *sdp = GFS2_SB(dir);
 489         struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
 490         struct gfs2_holder ghs[3];
 491         struct gfs2_rgrpd *rgd;
 492         struct gfs2_holder ri_gh;
 493         int error;
 494
 495         error = gfs2_rindex_hold(sdp, &ri_gh);
 496         if (error)
 497                 return error;
 498         gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
 499         gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + 1);
 500
 501         rgd = gfs2_blk2rgrpd(sdp, ip->i_no_addr);
 502         gfs2_holder_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, ghs + 2);
 503
 504         error = gfs2_glock_nq(ghs); /* parent */
 505         if (error)
 506                 goto out_parent;
 507
 508         error = gfs2_glock_nq(ghs + 1); /* child */
 509         if (error)
 510                 goto out_child;
 511
 512         error = gfs2_glock_nq(ghs + 2); /* rgrp */
 513         if (error)
 514                 goto out_rgrp;
 515
 516         error = gfs2_unlink_ok(dip, &dentry->d_name, ip);
 517         if (error)
 518                 goto out_gunlock;
 519
 520         if (ip->i_di.di_entries < 2) {
 521                 if (gfs2_consist_inode(ip))
 522                         gfs2_dinode_print(ip);
 523                 error = -EIO;
 524                 goto out_gunlock;
 525         }
 526         if (ip->i_di.di_entries > 2) {
 527                 error = -ENOTEMPTY;
 528                 goto out_gunlock;
 529         }
 530
 531         error = gfs2_trans_begin(sdp, 2 * RES_DINODE + 3 * RES_LEAF + RES_RG_BIT, 0);
 532         if (error)
 533                 goto out_gunlock;
 534
 535         error = gfs2_rmdiri(dip, &dentry->d_name, ip);
 536
 537         gfs2_trans_end(sdp);
 538
 539 out_gunlock:
 540         gfs2_glock_dq(ghs + 2);
 541 out_rgrp:
 542         gfs2_holder_uninit(ghs + 2);
 543         gfs2_glock_dq(ghs + 1);
 544 out_child:
 545         gfs2_holder_uninit(ghs + 1);
 546         gfs2_glock_dq(ghs);
 547 out_parent:
 548         gfs2_holder_uninit(ghs);
 549         gfs2_glock_dq_uninit(&ri_gh);
 550         return error;
 551 }
 552
 553 /**
 554  * gfs2_mknod - Make a special file
 555  * @dir: The directory in which the special file will reside
 556  * @dentry: The dentry of the special file
 557  * @mode: The mode of the special file
 558  * @rdev: The device specification of the special file
 559  *
 560  */
 561
 562 static int gfs2_mknod(struct inode *dir, struct dentry *dentry, int mode,
 563                       dev_t dev)
 564 {
 565         struct gfs2_inode *dip = GFS2_I(dir);
 566         struct gfs2_sbd *sdp = GFS2_SB(dir);
 567         struct gfs2_holder ghs[2];
 568         struct inode *inode;
 569
 570         gfs2_holder_init(dip->i_gl, 0, 0, ghs);
 571
 572         inode = gfs2_createi(ghs, &dentry->d_name, mode, dev);
 573         if (IS_ERR(inode)) {
 574                 gfs2_holder_uninit(ghs);
 575                 return PTR_ERR(inode);
 576         }
 577
 578         gfs2_trans_end(sdp);
 579         if (dip->i_alloc->al_rgd)
 580                 gfs2_inplace_release(dip);
 581         gfs2_quota_unlock(dip);
 582         gfs2_alloc_put(dip);
 583
 584         gfs2_glock_dq_uninit_m(2, ghs);
 585
 586         d_instantiate(dentry, inode);
 587         mark_inode_dirty(inode);
 588
 589         return 0;
 590 }
 591
 592 /**
 593  * gfs2_rename - Rename a file
 594  * @odir: Parent directory of old file name
 595  * @odentry: The old dentry of the file
 596  * @ndir: Parent directory of new file name
 597  * @ndentry: The new dentry of the file
 598  *
 599  * Returns: errno
 600  */
 601
 602 static int gfs2_rename(struct inode *odir, struct dentry *odentry,
 603                        struct inode *ndir, struct dentry *ndentry)
 604 {
 605         struct gfs2_inode *odip = GFS2_I(odir);
 606         struct gfs2_inode *ndip = GFS2_I(ndir);
 607         struct gfs2_inode *ip = GFS2_I(odentry->d_inode);
 608         struct gfs2_inode *nip = NULL;
 609         struct gfs2_sbd *sdp = GFS2_SB(odir);
 610         struct gfs2_holder ghs[5], r_gh;
 611         struct gfs2_rgrpd *nrgd;
 612         unsigned int num_gh;
 613         int dir_rename = 0;
 614         int alloc_required;
 615         unsigned int x;
 616         int error;
 617
 618         if (ndentry->d_inode) {
 619                 nip = GFS2_I(ndentry->d_inode);
 620                 if (ip == nip)
 621                         return 0;
 622         }
 623
 624         /* Make sure we aren't trying to move a dirctory into it's subdir */
 625
 626         if (S_ISDIR(ip->i_inode.i_mode) && odip != ndip) {
 627                 dir_rename = 1;
 628
 629                 error = gfs2_glock_nq_init(sdp->sd_rename_gl, LM_ST_EXCLUSIVE, 0,
 630                                            &r_gh);
 631                 if (error)
 632                         goto out;
 633
 634                 error = gfs2_ok_to_move(ip, ndip);
 635                 if (error)
 636                         goto out_gunlock_r;
 637         }
 638
 639         num_gh = 1;
 640         gfs2_holder_init(odip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
 641         if (odip != ndip) {
 642                 gfs2_holder_init(ndip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
 643                 num_gh++;
 644         }
 645         gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
 646         num_gh++;
 647
 648         if (nip) {
 649                 gfs2_holder_init(nip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
 650                 num_gh++;
 651                 /* grab the resource lock for unlink flag twiddling
 652                  * this is the case of the target file already existing
 653                  * so we unlink before doing the rename
 654                  */
 655                 nrgd = gfs2_blk2rgrpd(sdp, nip->i_no_addr);
 656                 if (nrgd)
 657                         gfs2_holder_init(nrgd->rd_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh++);
 658         }
 659
 660         for (x = 0; x < num_gh; x++) {
 661                 error = gfs2_glock_nq(ghs + x);
 662                 if (error)
 663                         goto out_gunlock;
 664         }
 665
 666         /* Check out the old directory */
 667
 668         error = gfs2_unlink_ok(odip, &odentry->d_name, ip);
 669         if (error)
 670                 goto out_gunlock;
 671
 672         /* Check out the new directory */
 673
 674         if (nip) {
 675                 error = gfs2_unlink_ok(ndip, &ndentry->d_name, nip);
 676                 if (error)
 677                         goto out_gunlock;
 678
 679                 if (S_ISDIR(nip->i_inode.i_mode)) {
 680                         if (nip->i_di.di_entries < 2) {
 681                                 if (gfs2_consist_inode(nip))
 682                                         gfs2_dinode_print(nip);
 683                                 error = -EIO;
 684                                 goto out_gunlock;
 685                         }
 686                         if (nip->i_di.di_entries > 2) {
 687                                 error = -ENOTEMPTY;
 688                                 goto out_gunlock;
 689                         }
 690                 }
 691         } else {
 692                 error = gfs2_permission(ndir, MAY_WRITE | MAY_EXEC);
 693                 if (error)
 694                         goto out_gunlock;
 695
 696                 error = gfs2_dir_check(ndir, &ndentry->d_name, NULL);
 697                 switch (error) {
 698                 case -ENOENT:
 699                         error = 0;
 700                         break;
 701                 case 0:
 702                         error = -EEXIST;
 703                 default:
 704                         goto out_gunlock;
 705                 };
 706
 707                 if (odip != ndip) {
 708                         if (!ndip->i_inode.i_nlink) {
 709                                 error = -EINVAL;
 710                                 goto out_gunlock;
 711                         }
 712                         if (ndip->i_di.di_entries == (u32)-1) {
 713                                 error = -EFBIG;
 714                                 goto out_gunlock;
 715                         }
 716                         if (S_ISDIR(ip->i_inode.i_mode) &&
 717                             ndip->i_inode.i_nlink == (u32)-1) {
 718                                 error = -EMLINK;
 719                                 goto out_gunlock;
 720                         }
 721                 }
 722         }
 723
 724         /* Check out the dir to be renamed */
 725
 726         if (dir_rename) {
 727                 error = gfs2_permission(odentry->d_inode, MAY_WRITE);
 728                 if (error)
 729                         goto out_gunlock;
 730         }
 731
 732         alloc_required = error = gfs2_diradd_alloc_required(ndir, &ndentry->d_name);
 733         if (error < 0)
 734                 goto out_gunlock;
 735         error = 0;
 736
 737         if (alloc_required) {
 738                 struct gfs2_alloc *al = gfs2_alloc_get(ndip);
 739                 if (!al) {
 740                         error = -ENOMEM;
 741                         goto out_gunlock;
 742                 }
 743
 744                 error = gfs2_quota_lock_check(ndip);
 745                 if (error)
 746                         goto out_alloc;
 747
 748                 al->al_requested = sdp->sd_max_dirres;
 749
 750                 error = gfs2_inplace_reserve(ndip);
 751                 if (error)
 752                         goto out_gunlock_q;
 753
 754                 error = gfs2_trans_begin(sdp, sdp->sd_max_dirres +
 755                                          al->al_rgd->rd_length +
 756                                          4 * RES_DINODE + 4 * RES_LEAF +
 757                                          RES_STATFS + RES_QUOTA + 4, 0);
 758                 if (error)
 759                         goto out_ipreserv;
 760         } else {
 761                 error = gfs2_trans_begin(sdp, 4 * RES_DINODE +
 762                                          5 * RES_LEAF + 4, 0);
 763                 if (error)
 764                         goto out_gunlock;
 765         }
 766
 767         /* Remove the target file, if it exists */
 768
 769         if (nip) {
 770                 if (S_ISDIR(nip->i_inode.i_mode))
 771                         error = gfs2_rmdiri(ndip, &ndentry->d_name, nip);
 772                 else {
 773                         error = gfs2_dir_del(ndip, &ndentry->d_name);
 774                         if (error)
 775                                 goto out_end_trans;
 776                         error = gfs2_change_nlink(nip, -1);
 777                 }
 778                 if (error)
 779                         goto out_end_trans;
 780         }
 781
 782         if (dir_rename) {
 783                 struct qstr name;
 784                 gfs2_str2qstr(&name, "..");
 785
 786                 error = gfs2_change_nlink(ndip, +1);
 787                 if (error)
 788                         goto out_end_trans;
 789                 error = gfs2_change_nlink(odip, -1);
 790                 if (error)
 791                         goto out_end_trans;
 792
 793                 error = gfs2_dir_mvino(ip, &name, ndip, DT_DIR);
 794                 if (error)
 795                         goto out_end_trans;
 796         } else {
 797                 struct buffer_head *dibh;
 798                 error = gfs2_meta_inode_buffer(ip, &dibh);
 799                 if (error)
 800                         goto out_end_trans;
 801                 ip->i_inode.i_ctime = CURRENT_TIME;
 802                 gfs2_trans_add_bh(ip->i_gl, dibh, 1);
 803                 gfs2_dinode_out(ip, dibh->b_data);
 804                 brelse(dibh);
 805         }
 806
 807         error = gfs2_dir_del(odip, &odentry->d_name);
 808         if (error)
 809                 goto out_end_trans;
 810
 811         error = gfs2_dir_add(ndir, &ndentry->d_name, ip, IF2DT(ip->i_inode.i_mode));
 812         if (error)
 813                 goto out_end_trans;
 814
 815 out_end_trans:
 816         gfs2_trans_end(sdp);
 817 out_ipreserv:
 818         if (alloc_required)
 819                 gfs2_inplace_release(ndip);
 820 out_gunlock_q:
 821         if (alloc_required)
 822                 gfs2_quota_unlock(ndip);
 823 out_alloc:
 824         if (alloc_required)
 825                 gfs2_alloc_put(ndip);
 826 out_gunlock:
 827         while (x--) {
 828                 gfs2_glock_dq(ghs + x);
 829                 gfs2_holder_uninit(ghs + x);
 830         }
 831 out_gunlock_r:
 832         if (dir_rename)
 833                 gfs2_glock_dq_uninit(&r_gh);
 834 out:
 835         return error;
 836 }
 837
 838 /**
 839  * gfs2_readlink - Read the value of a symlink
 840  * @dentry: the symlink
 841  * @buf: the buffer to read the symlink data into
 842  * @size: the size of the buffer
 843  *
 844  * Returns: errno
 845  */
 846
 847 static int gfs2_readlink(struct dentry *dentry, char __user *user_buf,
 848                          int user_size)
 849 {
 850         struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
 851         char array[GFS2_FAST_NAME_SIZE], *buf = array;
 852         unsigned int len = GFS2_FAST_NAME_SIZE;
 853         int error;
 854
 855         error = gfs2_readlinki(ip, &buf, &len);
 856         if (error)
 857                 return error;
 858
 859         if (user_size > len - 1)
 860                 user_size = len - 1;
 861
 862         if (copy_to_user(user_buf, buf, user_size))
 863                 error = -EFAULT;
 864         else
 865                 error = user_size;
 866
 867         if (buf != array)
 868                 kfree(buf);
 869
 870         return error;
 871 }
 872
 873 /**
 874  * gfs2_follow_link - Follow a symbolic link
 875  * @dentry: The dentry of the link
 876  * @nd: Data that we pass to vfs_follow_link()
 877  *
 878  * This can handle symlinks of any size. It is optimised for symlinks
 879  * under GFS2_FAST_NAME_SIZE.
 880  *
 881  * Returns: 0 on success or error code
 882  */
 883
 884 static void *gfs2_follow_link(struct dentry *dentry, struct nameidata *nd)
 885 {
 886         struct gfs2_inode *ip = GFS2_I(dentry->d_inode);
 887         char array[GFS2_FAST_NAME_SIZE], *buf = array;
 888         unsigned int len = GFS2_FAST_NAME_SIZE;
 889         int error;
 890
 891         error = gfs2_readlinki(ip, &buf, &len);
 892         if (!error) {
 893                 error = vfs_follow_link(nd, buf);
 894                 if (buf != array)
 895                         kfree(buf);
 896         }
 897
 898         return ERR_PTR(error);
 899 }
 900
 901 /**
 902  * gfs2_permission -
 903  * @inode:
 904  * @mask:
 905  * @nd: passed from Linux VFS, ignored by us
 906  *
 907  * This may be called from the VFS directly, or from within GFS2 with the
 908  * inode locked, so we look to see if the glock is already locked and only
 909  * lock the glock if its not already been done.
 910  *
 911  * Returns: errno
 912  */
 913
 914 int gfs2_permission(struct inode *inode, int mask)
 915 {
 916         struct gfs2_inode *ip = GFS2_I(inode);
 917         struct gfs2_holder i_gh;
 918         int error;
 919         int unlock = 0;
 920
 921         if (gfs2_glock_is_locked_by_me(ip->i_gl) == NULL) {
 922                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
 923                 if (error)
 924                         return error;
 925                 unlock = 1;
 926         }
 927
 928         if ((mask & MAY_WRITE) && IS_IMMUTABLE(inode))
 929                 error = -EACCES;
 930         else
 931                 error = generic_permission(inode, mask, gfs2_check_acl);
 932         if (unlock)
 933                 gfs2_glock_dq_uninit(&i_gh);
 934
 935         return error;
 936 }
 937
 938 static int setattr_size(struct inode *inode, struct iattr *attr)
 939 {
 940         struct gfs2_inode *ip = GFS2_I(inode);
 941         struct gfs2_sbd *sdp = GFS2_SB(inode);
 942         int error;
 943
 944         if (attr->ia_size != ip->i_di.di_size) {
 945                 error = gfs2_trans_begin(sdp, 0, sdp->sd_jdesc->jd_blocks);
 946                 if (error)
 947                         return error;
 948                 error = vmtruncate(inode, attr->ia_size);
 949                 gfs2_trans_end(sdp);
 950                 if (error)
 951                         return error;
 952         }
 953
 954         error = gfs2_truncatei(ip, attr->ia_size);
 955         if (error && (inode->i_size != ip->i_di.di_size))
 956                 i_size_write(inode, ip->i_di.di_size);
 957
 958         return error;
 959 }
 960
 961 static int setattr_chown(struct inode *inode, struct iattr *attr)
 962 {
 963         struct gfs2_inode *ip = GFS2_I(inode);
 964         struct gfs2_sbd *sdp = GFS2_SB(inode);
 965         struct buffer_head *dibh;
 966         u32 ouid, ogid, nuid, ngid;
 967         int error;
 968
 969         ouid = inode->i_uid;
 970         ogid = inode->i_gid;
 971         nuid = attr->ia_uid;
 972         ngid = attr->ia_gid;
 973
 974         if (!(attr->ia_valid & ATTR_UID) || ouid == nuid)
 975                 ouid = nuid = NO_QUOTA_CHANGE;
 976         if (!(attr->ia_valid & ATTR_GID) || ogid == ngid)
 977                 ogid = ngid = NO_QUOTA_CHANGE;
 978
 979         if (!gfs2_alloc_get(ip))
 980                 return -ENOMEM;
 981
 982         error = gfs2_quota_lock(ip, nuid, ngid);
 983         if (error)
 984                 goto out_alloc;
 985
 986         if (ouid != NO_QUOTA_CHANGE || ogid != NO_QUOTA_CHANGE) {
 987                 error = gfs2_quota_check(ip, nuid, ngid);
 988                 if (error)
 989                         goto out_gunlock_q;
 990         }
 991
 992         error = gfs2_trans_begin(sdp, RES_DINODE + 2 * RES_QUOTA, 0);
 993         if (error)
 994                 goto out_gunlock_q;
 995
 996         error = gfs2_meta_inode_buffer(ip, &dibh);
 997         if (error)
 998                 goto out_end_trans;
 999
1000         error = inode_setattr(inode, attr);
1001         gfs2_assert_warn(sdp, !error);
1002
1003         gfs2_trans_add_bh(ip->i_gl, dibh, 1);
1004         gfs2_dinode_out(ip, dibh->b_data);
1005         brelse(dibh);
1006
1007         if (ouid != NO_QUOTA_CHANGE || ogid != NO_QUOTA_CHANGE) {
1008                 u64 blocks = gfs2_get_inode_blocks(&ip->i_inode);
1009                 gfs2_quota_change(ip, -blocks, ouid, ogid);
1010                 gfs2_quota_change(ip, blocks, nuid, ngid);
1011         }
1012
1013 out_end_trans:
1014         gfs2_trans_end(sdp);
1015 out_gunlock_q:
1016         gfs2_quota_unlock(ip);
1017 out_alloc:
1018         gfs2_alloc_put(ip);
1019         return error;
1020 }
1021
1022 /**
1023  * gfs2_setattr - Change attributes on an inode
1024  * @dentry: The dentry which is changing
1025  * @attr: The structure describing the change
1026  *
1027  * The VFS layer wants to change one or more of an inodes attributes.  Write
1028  * that change out to disk.
1029  *
1030  * Returns: errno
1031  */
1032
1033 static int gfs2_setattr(struct dentry *dentry, struct iattr *attr)
1034 {
1035         struct inode *inode = dentry->d_inode;
1036         struct gfs2_inode *ip = GFS2_I(inode);
1037         struct gfs2_holder i_gh;
1038         int error;
1039
1040         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
1041         if (error)
1042                 return error;
1043
1044         error = -EPERM;
1045         if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
1046                 goto out;
1047
1048         error = inode_change_ok(inode, attr);
1049         if (error)
1050                 goto out;
1051
1052         if (attr->ia_valid & ATTR_SIZE)
1053                 error = setattr_size(inode, attr);
1054         else if (attr->ia_valid & (ATTR_UID | ATTR_GID))
1055                 error = setattr_chown(inode, attr);
1056         else if ((attr->ia_valid & ATTR_MODE) && IS_POSIXACL(inode))
1057                 error = gfs2_acl_chmod(ip, attr);
1058         else
1059                 error = gfs2_setattr_simple(ip, attr);
1060
1061 out:
1062         gfs2_glock_dq_uninit(&i_gh);
1063         if (!error)
1064                 mark_inode_dirty(inode);
1065         return error;
1066 }
1067
1068 /**
1069  * gfs2_getattr - Read out an inode's attributes
1070  * @mnt: The vfsmount the inode is being accessed from
1071  * @dentry: The dentry to stat
1072  * @stat: The inode's stats
1073  *
1074  * This may be called from the VFS directly, or from within GFS2 with the
1075  * inode locked, so we look to see if the glock is already locked and only
1076  * lock the glock if its not already been done. Note that its the NFS
1077  * readdirplus operation which causes this to be called (from filldir)
1078  * with the glock already held.
1079  *
1080  * Returns: errno
1081  */
1082
1083 static int gfs2_getattr(struct vfsmount *mnt, struct dentry *dentry,
1084                         struct kstat *stat)
1085 {
1086         struct inode *inode = dentry->d_inode;
1087         struct gfs2_inode *ip = GFS2_I(inode);
1088         struct gfs2_holder gh;
1089         int error;
1090         int unlock = 0;
1091
1092         if (gfs2_glock_is_locked_by_me(ip->i_gl) == NULL) {
1093                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
1094                 if (error)
1095                         return error;
1096                 unlock = 1;
1097         }
1098
1099         generic_fillattr(inode, stat);
1100         if (unlock)
1101                 gfs2_glock_dq_uninit(&gh);
1102
1103         return 0;
1104 }
1105
1106 static int gfs2_setxattr(struct dentry *dentry, const char *name,
1107                          const void *data, size_t size, int flags)
1108 {
1109         struct inode *inode = dentry->d_inode;
1110         struct gfs2_ea_request er;
1111
1112         memset(&er, 0, sizeof(struct gfs2_ea_request));
1113         er.er_type = gfs2_ea_name2type(name, &er.er_name);
1114         if (er.er_type == GFS2_EATYPE_UNUSED)
1115                 return -EOPNOTSUPP;
1116         er.er_data = (char *)data;
1117         er.er_name_len = strlen(er.er_name);
1118         er.er_data_len = size;
1119         er.er_flags = flags;
1120
1121         gfs2_assert_warn(GFS2_SB(inode), !(er.er_flags & GFS2_ERF_MODE));
1122
1123         return gfs2_ea_set(GFS2_I(inode), &er);
1124 }
1125
1126 static ssize_t gfs2_getxattr(struct dentry *dentry, const char *name,
1127                              void *data, size_t size)
1128 {
1129         struct gfs2_ea_request er;
1130
1131         memset(&er, 0, sizeof(struct gfs2_ea_request));
1132         er.er_type = gfs2_ea_name2type(name, &er.er_name);
1133         if (er.er_type == GFS2_EATYPE_UNUSED)
1134                 return -EOPNOTSUPP;
1135         er.er_data = data;
1136         er.er_name_len = strlen(er.er_name);
1137         er.er_data_len = size;
1138
1139         return gfs2_ea_get(GFS2_I(dentry->d_inode), &er);
1140 }
1141
1142 static ssize_t gfs2_listxattr(struct dentry *dentry, char *buffer, size_t size)
1143 {
1144         struct gfs2_ea_request er;
1145
1146         memset(&er, 0, sizeof(struct gfs2_ea_request));
1147         er.er_data = (size) ? buffer : NULL;
1148         er.er_data_len = size;
1149
1150         return gfs2_ea_list(GFS2_I(dentry->d_inode), &er);
1151 }
1152
1153 static int gfs2_removexattr(struct dentry *dentry, const char *name)
1154 {
1155         struct gfs2_ea_request er;
1156
1157         memset(&er, 0, sizeof(struct gfs2_ea_request));
1158         er.er_type = gfs2_ea_name2type(name, &er.er_name);
1159         if (er.er_type == GFS2_EATYPE_UNUSED)
1160                 return -EOPNOTSUPP;
1161         er.er_name_len = strlen(er.er_name);
1162
1163         return gfs2_ea_remove(GFS2_I(dentry->d_inode), &er);
1164 }
1165
1166 const struct inode_operations gfs2_file_iops = {
1167         .permission = gfs2_permission,
1168         .setattr = gfs2_setattr,
1169         .getattr = gfs2_getattr,
1170         .setxattr = gfs2_setxattr,
1171         .getxattr = gfs2_getxattr,
1172         .listxattr = gfs2_listxattr,
1173         .removexattr = gfs2_removexattr,
1174 };
1175
1176 const struct inode_operations gfs2_dir_iops = {
1177         .create = gfs2_create,
1178         .lookup = gfs2_lookup,
1179         .link = gfs2_link,
1180         .unlink = gfs2_unlink,
1181         .symlink = gfs2_symlink,
1182         .mkdir = gfs2_mkdir,
1183         .rmdir = gfs2_rmdir,
1184         .mknod = gfs2_mknod,
1185         .rename = gfs2_rename,
1186         .permission = gfs2_permission,
1187         .setattr = gfs2_setattr,
1188         .getattr = gfs2_getattr,
1189         .setxattr = gfs2_setxattr,
1190         .getxattr = gfs2_getxattr,
1191         .listxattr = gfs2_listxattr,
1192         .removexattr = gfs2_removexattr,
1193 };
1194
1195 const struct inode_operations gfs2_symlink_iops = {
1196         .readlink = gfs2_readlink,
1197         .follow_link = gfs2_follow_link,
1198         .permission = gfs2_permission,
1199         .setattr = gfs2_setattr,
1200         .getattr = gfs2_getattr,
1201         .setxattr = gfs2_setxattr,
1202         .getxattr = gfs2_getxattr,
1203         .listxattr = gfs2_listxattr,
1204         .removexattr = gfs2_removexattr,
1205 };
1206