fs/gfs2/super.c

   1 /*
   2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3  * Copyright (C) 2004-2007 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/bio.h>
  11 #include <linux/sched.h>
  12 #include <linux/slab.h>
  13 #include <linux/spinlock.h>
  14 #include <linux/completion.h>
  15 #include <linux/buffer_head.h>
  16 #include <linux/statfs.h>
  17 #include <linux/seq_file.h>
  18 #include <linux/mount.h>
  19 #include <linux/kthread.h>
  20 #include <linux/delay.h>
  21 #include <linux/gfs2_ondisk.h>
  22 #include <linux/crc32.h>
  23 #include <linux/time.h>
  24 #include <linux/wait.h>
  25 #include <linux/writeback.h>
  26
  27 #include "gfs2.h"
  28 #include "incore.h"
  29 #include "bmap.h"
  30 #include "dir.h"
  31 #include "glock.h"
  32 #include "glops.h"
  33 #include "inode.h"
  34 #include "log.h"
  35 #include "meta_io.h"
  36 #include "quota.h"
  37 #include "recovery.h"
  38 #include "rgrp.h"
  39 #include "super.h"
  40 #include "trans.h"
  41 #include "util.h"
  42 #include "sys.h"
  43 #include "xattr.h"
  44
  45 #define args_neq(a1, a2, x) ((a1)->ar_##x != (a2)->ar_##x)
  46
  47 enum {
  48         Opt_lockproto,
  49         Opt_locktable,
  50         Opt_hostdata,
  51         Opt_spectator,
  52         Opt_ignore_local_fs,
  53         Opt_localflocks,
  54         Opt_localcaching,
  55         Opt_debug,
  56         Opt_nodebug,
  57         Opt_upgrade,
  58         Opt_acl,
  59         Opt_noacl,
  60         Opt_quota_off,
  61         Opt_quota_account,
  62         Opt_quota_on,
  63         Opt_quota,
  64         Opt_noquota,
  65         Opt_suiddir,
  66         Opt_nosuiddir,
  67         Opt_data_writeback,
  68         Opt_data_ordered,
  69         Opt_meta,
  70         Opt_discard,
  71         Opt_nodiscard,
  72         Opt_commit,
  73         Opt_err_withdraw,
  74         Opt_err_panic,
  75         Opt_statfs_quantum,
  76         Opt_statfs_percent,
  77         Opt_quota_quantum,
  78         Opt_barrier,
  79         Opt_nobarrier,
  80         Opt_error,
  81 };
  82
  83 static const match_table_t tokens = {
  84         {Opt_lockproto, "lockproto=%s"},
  85         {Opt_locktable, "locktable=%s"},
  86         {Opt_hostdata, "hostdata=%s"},
  87         {Opt_spectator, "spectator"},
  88         {Opt_spectator, "norecovery"},
  89         {Opt_ignore_local_fs, "ignore_local_fs"},
  90         {Opt_localflocks, "localflocks"},
  91         {Opt_localcaching, "localcaching"},
  92         {Opt_debug, "debug"},
  93         {Opt_nodebug, "nodebug"},
  94         {Opt_upgrade, "upgrade"},
  95         {Opt_acl, "acl"},
  96         {Opt_noacl, "noacl"},
  97         {Opt_quota_off, "quota=off"},
  98         {Opt_quota_account, "quota=account"},
  99         {Opt_quota_on, "quota=on"},
 100         {Opt_quota, "quota"},
 101         {Opt_noquota, "noquota"},
 102         {Opt_suiddir, "suiddir"},
 103         {Opt_nosuiddir, "nosuiddir"},
 104         {Opt_data_writeback, "data=writeback"},
 105         {Opt_data_ordered, "data=ordered"},
 106         {Opt_meta, "meta"},
 107         {Opt_discard, "discard"},
 108         {Opt_nodiscard, "nodiscard"},
 109         {Opt_commit, "commit=%d"},
 110         {Opt_err_withdraw, "errors=withdraw"},
 111         {Opt_err_panic, "errors=panic"},
 112         {Opt_statfs_quantum, "statfs_quantum=%d"},
 113         {Opt_statfs_percent, "statfs_percent=%d"},
 114         {Opt_quota_quantum, "quota_quantum=%d"},
 115         {Opt_barrier, "barrier"},
 116         {Opt_nobarrier, "nobarrier"},
 117         {Opt_error, NULL}
 118 };
 119
 120 /**
 121  * gfs2_mount_args - Parse mount options
 122  * @args: The structure into which the parsed options will be written
 123  * @options: The options to parse
 124  *
 125  * Return: errno
 126  */
 127
 128 int gfs2_mount_args(struct gfs2_args *args, char *options)
 129 {
 130         char *o;
 131         int token;
 132         substring_t tmp[MAX_OPT_ARGS];
 133         int rv;
 134
 135         /* Split the options into tokens with the "," character and
 136            process them */
 137
 138         while (1) {
 139                 o = strsep(&options, ",");
 140                 if (o == NULL)
 141                         break;
 142                 if (*o == '\0')
 143                         continue;
 144
 145                 token = match_token(o, tokens, tmp);
 146                 switch (token) {
 147                 case Opt_lockproto:
 148                         match_strlcpy(args->ar_lockproto, &tmp[0],
 149                                       GFS2_LOCKNAME_LEN);
 150                         break;
 151                 case Opt_locktable:
 152                         match_strlcpy(args->ar_locktable, &tmp[0],
 153                                       GFS2_LOCKNAME_LEN);
 154                         break;
 155                 case Opt_hostdata:
 156                         match_strlcpy(args->ar_hostdata, &tmp[0],
 157                                       GFS2_LOCKNAME_LEN);
 158                         break;
 159                 case Opt_spectator:
 160                         args->ar_spectator = 1;
 161                         break;
 162                 case Opt_ignore_local_fs:
 163                         /* Retained for backwards compat only */
 164                         break;
 165                 case Opt_localflocks:
 166                         args->ar_localflocks = 1;
 167                         break;
 168                 case Opt_localcaching:
 169                         /* Retained for backwards compat only */
 170                         break;
 171                 case Opt_debug:
 172                         if (args->ar_errors == GFS2_ERRORS_PANIC) {
 173                                 printk(KERN_WARNING "GFS2: -o debug and -o errors=panic "
 174                                        "are mutually exclusive.\n");
 175                                 return -EINVAL;
 176                         }
 177                         args->ar_debug = 1;
 178                         break;
 179                 case Opt_nodebug:
 180                         args->ar_debug = 0;
 181                         break;
 182                 case Opt_upgrade:
 183                         /* Retained for backwards compat only */
 184                         break;
 185                 case Opt_acl:
 186                         args->ar_posix_acl = 1;
 187                         break;
 188                 case Opt_noacl:
 189                         args->ar_posix_acl = 0;
 190                         break;
 191                 case Opt_quota_off:
 192                 case Opt_noquota:
 193                         args->ar_quota = GFS2_QUOTA_OFF;
 194                         break;
 195                 case Opt_quota_account:
 196                         args->ar_quota = GFS2_QUOTA_ACCOUNT;
 197                         break;
 198                 case Opt_quota_on:
 199                 case Opt_quota:
 200                         args->ar_quota = GFS2_QUOTA_ON;
 201                         break;
 202                 case Opt_suiddir:
 203                         args->ar_suiddir = 1;
 204                         break;
 205                 case Opt_nosuiddir:
 206                         args->ar_suiddir = 0;
 207                         break;
 208                 case Opt_data_writeback:
 209                         args->ar_data = GFS2_DATA_WRITEBACK;
 210                         break;
 211                 case Opt_data_ordered:
 212                         args->ar_data = GFS2_DATA_ORDERED;
 213                         break;
 214                 case Opt_meta:
 215                         args->ar_meta = 1;
 216                         break;
 217                 case Opt_discard:
 218                         args->ar_discard = 1;
 219                         break;
 220                 case Opt_nodiscard:
 221                         args->ar_discard = 0;
 222                         break;
 223                 case Opt_commit:
 224                         rv = match_int(&tmp[0], &args->ar_commit);
 225                         if (rv || args->ar_commit <= 0) {
 226                                 printk(KERN_WARNING "GFS2: commit mount option requires a positive numeric argument\n");
 227                                 return rv ? rv : -EINVAL;
 228                         }
 229                         break;
 230                 case Opt_statfs_quantum:
 231                         rv = match_int(&tmp[0], &args->ar_statfs_quantum);
 232                         if (rv || args->ar_statfs_quantum < 0) {
 233                                 printk(KERN_WARNING "GFS2: statfs_quantum mount option requires a non-negative numeric argument\n");
 234                                 return rv ? rv : -EINVAL;
 235                         }
 236                         break;
 237                 case Opt_quota_quantum:
 238                         rv = match_int(&tmp[0], &args->ar_quota_quantum);
 239                         if (rv || args->ar_quota_quantum <= 0) {
 240                                 printk(KERN_WARNING "GFS2: quota_quantum mount option requires a positive numeric argument\n");
 241                                 return rv ? rv : -EINVAL;
 242                         }
 243                         break;
 244                 case Opt_statfs_percent:
 245                         rv = match_int(&tmp[0], &args->ar_statfs_percent);
 246                         if (rv || args->ar_statfs_percent < 0 ||
 247                             args->ar_statfs_percent > 100) {
 248                                 printk(KERN_WARNING "statfs_percent mount option requires a numeric argument between 0 and 100\n");
 249                                 return rv ? rv : -EINVAL;
 250                         }
 251                         break;
 252                 case Opt_err_withdraw:
 253                         args->ar_errors = GFS2_ERRORS_WITHDRAW;
 254                         break;
 255                 case Opt_err_panic:
 256                         if (args->ar_debug) {
 257                                 printk(KERN_WARNING "GFS2: -o debug and -o errors=panic "
 258                                         "are mutually exclusive.\n");
 259                                 return -EINVAL;
 260                         }
 261                         args->ar_errors = GFS2_ERRORS_PANIC;
 262                         break;
 263                 case Opt_barrier:
 264                         args->ar_nobarrier = 0;
 265                         break;
 266                 case Opt_nobarrier:
 267                         args->ar_nobarrier = 1;
 268                         break;
 269                 case Opt_error:
 270                 default:
 271                         printk(KERN_WARNING "GFS2: invalid mount option: %s\n", o);
 272                         return -EINVAL;
 273                 }
 274         }
 275
 276         return 0;
 277 }
 278
 279 /**
 280  * gfs2_jindex_free - Clear all the journal index information
 281  * @sdp: The GFS2 superblock
 282  *
 283  */
 284
 285 void gfs2_jindex_free(struct gfs2_sbd *sdp)
 286 {
 287         struct list_head list, *head;
 288         struct gfs2_jdesc *jd;
 289         struct gfs2_journal_extent *jext;
 290
 291         spin_lock(&sdp->sd_jindex_spin);
 292         list_add(&list, &sdp->sd_jindex_list);
 293         list_del_init(&sdp->sd_jindex_list);
 294         sdp->sd_journals = 0;
 295         spin_unlock(&sdp->sd_jindex_spin);
 296
 297         while (!list_empty(&list)) {
 298                 jd = list_entry(list.next, struct gfs2_jdesc, jd_list);
 299                 head = &jd->extent_list;
 300                 while (!list_empty(head)) {
 301                         jext = list_entry(head->next,
 302                                           struct gfs2_journal_extent,
 303                                           extent_list);
 304                         list_del(&jext->extent_list);
 305                         kfree(jext);
 306                 }
 307                 list_del(&jd->jd_list);
 308                 iput(jd->jd_inode);
 309                 kfree(jd);
 310         }
 311 }
 312
 313 static struct gfs2_jdesc *jdesc_find_i(struct list_head *head, unsigned int jid)
 314 {
 315         struct gfs2_jdesc *jd;
 316         int found = 0;
 317
 318         list_for_each_entry(jd, head, jd_list) {
 319                 if (jd->jd_jid == jid) {
 320                         found = 1;
 321                         break;
 322                 }
 323         }
 324
 325         if (!found)
 326                 jd = NULL;
 327
 328         return jd;
 329 }
 330
 331 struct gfs2_jdesc *gfs2_jdesc_find(struct gfs2_sbd *sdp, unsigned int jid)
 332 {
 333         struct gfs2_jdesc *jd;
 334
 335         spin_lock(&sdp->sd_jindex_spin);
 336         jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
 337         spin_unlock(&sdp->sd_jindex_spin);
 338
 339         return jd;
 340 }
 341
 342 int gfs2_jdesc_check(struct gfs2_jdesc *jd)
 343 {
 344         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
 345         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 346         u64 size = i_size_read(jd->jd_inode);
 347
 348         if (gfs2_check_internal_file_size(jd->jd_inode, 8 << 20, 1 << 30))
 349                 return -EIO;
 350
 351         jd->jd_blocks = size >> sdp->sd_sb.sb_bsize_shift;
 352
 353         if (gfs2_write_alloc_required(ip, 0, size)) {
 354                 gfs2_consist_inode(ip);
 355                 return -EIO;
 356         }
 357
 358         return 0;
 359 }
 360
 361 /**
 362  * gfs2_make_fs_rw - Turn a Read-Only FS into a Read-Write one
 363  * @sdp: the filesystem
 364  *
 365  * Returns: errno
 366  */
 367
 368 int gfs2_make_fs_rw(struct gfs2_sbd *sdp)
 369 {
 370         struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
 371         struct gfs2_glock *j_gl = ip->i_gl;
 372         struct gfs2_holder t_gh;
 373         struct gfs2_log_header_host head;
 374         int error;
 375
 376         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED, 0, &t_gh);
 377         if (error)
 378                 return error;
 379
 380         j_gl->gl_ops->go_inval(j_gl, DIO_METADATA);
 381
 382         error = gfs2_find_jhead(sdp->sd_jdesc, &head);
 383         if (error)
 384                 goto fail;
 385
 386         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 387                 gfs2_consist(sdp);
 388                 error = -EIO;
 389                 goto fail;
 390         }
 391
 392         /*  Initialize some head of the log stuff  */
 393         sdp->sd_log_sequence = head.lh_sequence + 1;
 394         gfs2_log_pointers_init(sdp, head.lh_blkno);
 395
 396         error = gfs2_quota_init(sdp);
 397         if (error)
 398                 goto fail;
 399
 400         set_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 401
 402         gfs2_glock_dq_uninit(&t_gh);
 403
 404         return 0;
 405
 406 fail:
 407         t_gh.gh_flags |= GL_NOCACHE;
 408         gfs2_glock_dq_uninit(&t_gh);
 409
 410         return error;
 411 }
 412
 413 void gfs2_statfs_change_in(struct gfs2_statfs_change_host *sc, const void *buf)
 414 {
 415         const struct gfs2_statfs_change *str = buf;
 416
 417         sc->sc_total = be64_to_cpu(str->sc_total);
 418         sc->sc_free = be64_to_cpu(str->sc_free);
 419         sc->sc_dinodes = be64_to_cpu(str->sc_dinodes);
 420 }
 421
 422 static void gfs2_statfs_change_out(const struct gfs2_statfs_change_host *sc, void *buf)
 423 {
 424         struct gfs2_statfs_change *str = buf;
 425
 426         str->sc_total = cpu_to_be64(sc->sc_total);
 427         str->sc_free = cpu_to_be64(sc->sc_free);
 428         str->sc_dinodes = cpu_to_be64(sc->sc_dinodes);
 429 }
 430
 431 int gfs2_statfs_init(struct gfs2_sbd *sdp)
 432 {
 433         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 434         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 435         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 436         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 437         struct buffer_head *m_bh, *l_bh;
 438         struct gfs2_holder gh;
 439         int error;
 440
 441         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 442                                    &gh);
 443         if (error)
 444                 return error;
 445
 446         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 447         if (error)
 448                 goto out;
 449
 450         if (sdp->sd_args.ar_spectator) {
 451                 spin_lock(&sdp->sd_statfs_spin);
 452                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 453                                       sizeof(struct gfs2_dinode));
 454                 spin_unlock(&sdp->sd_statfs_spin);
 455         } else {
 456                 error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 457                 if (error)
 458                         goto out_m_bh;
 459
 460                 spin_lock(&sdp->sd_statfs_spin);
 461                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 462                                       sizeof(struct gfs2_dinode));
 463                 gfs2_statfs_change_in(l_sc, l_bh->b_data +
 464                                       sizeof(struct gfs2_dinode));
 465                 spin_unlock(&sdp->sd_statfs_spin);
 466
 467                 brelse(l_bh);
 468         }
 469
 470 out_m_bh:
 471         brelse(m_bh);
 472 out:
 473         gfs2_glock_dq_uninit(&gh);
 474         return 0;
 475 }
 476
 477 void gfs2_statfs_change(struct gfs2_sbd *sdp, s64 total, s64 free,
 478                         s64 dinodes)
 479 {
 480         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 481         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 482         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 483         struct buffer_head *l_bh;
 484         s64 x, y;
 485         int need_sync = 0;
 486         int error;
 487
 488         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 489         if (error)
 490                 return;
 491
 492         gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
 493
 494         spin_lock(&sdp->sd_statfs_spin);
 495         l_sc->sc_total += total;
 496         l_sc->sc_free += free;
 497         l_sc->sc_dinodes += dinodes;
 498         gfs2_statfs_change_out(l_sc, l_bh->b_data + sizeof(struct gfs2_dinode));
 499         if (sdp->sd_args.ar_statfs_percent) {
 500                 x = 100 * l_sc->sc_free;
 501                 y = m_sc->sc_free * sdp->sd_args.ar_statfs_percent;
 502                 if (x >= y || x <= -y)
 503                         need_sync = 1;
 504         }
 505         spin_unlock(&sdp->sd_statfs_spin);
 506
 507         brelse(l_bh);
 508         if (need_sync)
 509                 gfs2_wake_up_statfs(sdp);
 510 }
 511
 512 void update_statfs(struct gfs2_sbd *sdp, struct buffer_head *m_bh,
 513                    struct buffer_head *l_bh)
 514 {
 515         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 516         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 517         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 518         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 519
 520         gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
 521
 522         spin_lock(&sdp->sd_statfs_spin);
 523         m_sc->sc_total += l_sc->sc_total;
 524         m_sc->sc_free += l_sc->sc_free;
 525         m_sc->sc_dinodes += l_sc->sc_dinodes;
 526         memset(l_sc, 0, sizeof(struct gfs2_statfs_change));
 527         memset(l_bh->b_data + sizeof(struct gfs2_dinode),
 528                0, sizeof(struct gfs2_statfs_change));
 529         spin_unlock(&sdp->sd_statfs_spin);
 530
 531         gfs2_trans_add_bh(m_ip->i_gl, m_bh, 1);
 532         gfs2_statfs_change_out(m_sc, m_bh->b_data + sizeof(struct gfs2_dinode));
 533 }
 534
 535 int gfs2_statfs_sync(struct super_block *sb, int type)
 536 {
 537         struct gfs2_sbd *sdp = sb->s_fs_info;
 538         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 539         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 540         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 541         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 542         struct gfs2_holder gh;
 543         struct buffer_head *m_bh, *l_bh;
 544         int error;
 545
 546         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 547                                    &gh);
 548         if (error)
 549                 return error;
 550
 551         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 552         if (error)
 553                 goto out;
 554
 555         spin_lock(&sdp->sd_statfs_spin);
 556         gfs2_statfs_change_in(m_sc, m_bh->b_data +
 557                               sizeof(struct gfs2_dinode));
 558         if (!l_sc->sc_total && !l_sc->sc_free && !l_sc->sc_dinodes) {
 559                 spin_unlock(&sdp->sd_statfs_spin);
 560                 goto out_bh;
 561         }
 562         spin_unlock(&sdp->sd_statfs_spin);
 563
 564         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 565         if (error)
 566                 goto out_bh;
 567
 568         error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
 569         if (error)
 570                 goto out_bh2;
 571
 572         update_statfs(sdp, m_bh, l_bh);
 573         sdp->sd_statfs_force_sync = 0;
 574
 575         gfs2_trans_end(sdp);
 576
 577 out_bh2:
 578         brelse(l_bh);
 579 out_bh:
 580         brelse(m_bh);
 581 out:
 582         gfs2_glock_dq_uninit(&gh);
 583         return error;
 584 }
 585
 586 struct lfcc {
 587         struct list_head list;
 588         struct gfs2_holder gh;
 589 };
 590
 591 /**
 592  * gfs2_lock_fs_check_clean - Stop all writes to the FS and check that all
 593  *                            journals are clean
 594  * @sdp: the file system
 595  * @state: the state to put the transaction lock into
 596  * @t_gh: the hold on the transaction lock
 597  *
 598  * Returns: errno
 599  */
 600
 601 static int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp,
 602                                     struct gfs2_holder *t_gh)
 603 {
 604         struct gfs2_inode *ip;
 605         struct gfs2_jdesc *jd;
 606         struct lfcc *lfcc;
 607         LIST_HEAD(list);
 608         struct gfs2_log_header_host lh;
 609         int error;
 610
 611         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 612                 lfcc = kmalloc(sizeof(struct lfcc), GFP_KERNEL);
 613                 if (!lfcc) {
 614                         error = -ENOMEM;
 615                         goto out;
 616                 }
 617                 ip = GFS2_I(jd->jd_inode);
 618                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &lfcc->gh);
 619                 if (error) {
 620                         kfree(lfcc);
 621                         goto out;
 622                 }
 623                 list_add(&lfcc->list, &list);
 624         }
 625
 626         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_DEFERRED,
 627                                    GL_NOCACHE, t_gh);
 628
 629         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 630                 error = gfs2_jdesc_check(jd);
 631                 if (error)
 632                         break;
 633                 error = gfs2_find_jhead(jd, &lh);
 634                 if (error)
 635                         break;
 636                 if (!(lh.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 637                         error = -EBUSY;
 638                         break;
 639                 }
 640         }
 641
 642         if (error)
 643                 gfs2_glock_dq_uninit(t_gh);
 644
 645 out:
 646         while (!list_empty(&list)) {
 647                 lfcc = list_entry(list.next, struct lfcc, list);
 648                 list_del(&lfcc->list);
 649                 gfs2_glock_dq_uninit(&lfcc->gh);
 650                 kfree(lfcc);
 651         }
 652         return error;
 653 }
 654
 655 /**
 656  * gfs2_freeze_fs - freezes the file system
 657  * @sdp: the file system
 658  *
 659  * This function flushes data and meta data for all machines by
 660  * acquiring the transaction log exclusively.  All journals are
 661  * ensured to be in a clean state as well.
 662  *
 663  * Returns: errno
 664  */
 665
 666 int gfs2_freeze_fs(struct gfs2_sbd *sdp)
 667 {
 668         int error = 0;
 669
 670         mutex_lock(&sdp->sd_freeze_lock);
 671
 672         if (!sdp->sd_freeze_count++) {
 673                 error = gfs2_lock_fs_check_clean(sdp, &sdp->sd_freeze_gh);
 674                 if (error)
 675                         sdp->sd_freeze_count--;
 676         }
 677
 678         mutex_unlock(&sdp->sd_freeze_lock);
 679
 680         return error;
 681 }
 682
 683 /**
 684  * gfs2_unfreeze_fs - unfreezes the file system
 685  * @sdp: the file system
 686  *
 687  * This function allows the file system to proceed by unlocking
 688  * the exclusively held transaction lock.  Other GFS2 nodes are
 689  * now free to acquire the lock shared and go on with their lives.
 690  *
 691  */
 692
 693 void gfs2_unfreeze_fs(struct gfs2_sbd *sdp)
 694 {
 695         mutex_lock(&sdp->sd_freeze_lock);
 696
 697         if (sdp->sd_freeze_count && !--sdp->sd_freeze_count)
 698                 gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
 699
 700         mutex_unlock(&sdp->sd_freeze_lock);
 701 }
 702
 703
 704 /**
 705  * gfs2_write_inode - Make sure the inode is stable on the disk
 706  * @inode: The inode
 707  * @sync: synchronous write flag
 708  *
 709  * Returns: errno
 710  */
 711
 712 static int gfs2_write_inode(struct inode *inode, struct writeback_control *wbc)
 713 {
 714         struct gfs2_inode *ip = GFS2_I(inode);
 715         struct gfs2_sbd *sdp = GFS2_SB(inode);
 716         struct gfs2_holder gh;
 717         struct buffer_head *bh;
 718         struct timespec atime;
 719         struct gfs2_dinode *di;
 720         int ret = 0;
 721
 722         /* Check this is a "normal" inode, etc */
 723         if (current->flags & PF_MEMALLOC)
 724                 return 0;
 725         ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
 726         if (ret)
 727                 goto do_flush;
 728         ret = gfs2_trans_begin(sdp, RES_DINODE, 0);
 729         if (ret)
 730                 goto do_unlock;
 731         ret = gfs2_meta_inode_buffer(ip, &bh);
 732         if (ret == 0) {
 733                 di = (struct gfs2_dinode *)bh->b_data;
 734                 atime.tv_sec = be64_to_cpu(di->di_atime);
 735                 atime.tv_nsec = be32_to_cpu(di->di_atime_nsec);
 736                 if (timespec_compare(&inode->i_atime, &atime) > 0) {
 737                         gfs2_trans_add_bh(ip->i_gl, bh, 1);
 738                         gfs2_dinode_out(ip, bh->b_data);
 739                 }
 740                 brelse(bh);
 741         }
 742         gfs2_trans_end(sdp);
 743 do_unlock:
 744         gfs2_glock_dq_uninit(&gh);
 745 do_flush:
 746         if (wbc->sync_mode == WB_SYNC_ALL)
 747                 gfs2_log_flush(GFS2_SB(inode), ip->i_gl);
 748         return ret;
 749 }
 750
 751 /**
 752  * gfs2_make_fs_ro - Turn a Read-Write FS into a Read-Only one
 753  * @sdp: the filesystem
 754  *
 755  * Returns: errno
 756  */
 757
 758 static int gfs2_make_fs_ro(struct gfs2_sbd *sdp)
 759 {
 760         struct gfs2_holder t_gh;
 761         int error;
 762
 763         flush_workqueue(gfs2_delete_workqueue);
 764         gfs2_quota_sync(sdp->sd_vfs, 0, 1);
 765         gfs2_statfs_sync(sdp->sd_vfs, 0);
 766
 767         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED, GL_NOCACHE,
 768                                    &t_gh);
 769         if (error && !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
 770                 return error;
 771
 772         gfs2_meta_syncfs(sdp);
 773         gfs2_log_shutdown(sdp);
 774
 775         clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 776
 777         if (t_gh.gh_gl)
 778                 gfs2_glock_dq_uninit(&t_gh);
 779
 780         gfs2_quota_cleanup(sdp);
 781
 782         return error;
 783 }
 784
 785 static int gfs2_umount_recovery_wait(void *word)
 786 {
 787         schedule();
 788         return 0;
 789 }
 790
 791 /**
 792  * gfs2_put_super - Unmount the filesystem
 793  * @sb: The VFS superblock
 794  *
 795  */
 796
 797 static void gfs2_put_super(struct super_block *sb)
 798 {
 799         struct gfs2_sbd *sdp = sb->s_fs_info;
 800         int error;
 801         struct gfs2_jdesc *jd;
 802
 803         /*  Unfreeze the filesystem, if we need to  */
 804
 805         mutex_lock(&sdp->sd_freeze_lock);
 806         if (sdp->sd_freeze_count)
 807                 gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
 808         mutex_unlock(&sdp->sd_freeze_lock);
 809
 810         /* No more recovery requests */
 811         set_bit(SDF_NORECOVERY, &sdp->sd_flags);
 812         smp_mb();
 813
 814         /* Wait on outstanding recovery */
 815 restart:
 816         spin_lock(&sdp->sd_jindex_spin);
 817         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 818                 if (!test_bit(JDF_RECOVERY, &jd->jd_flags))
 819                         continue;
 820                 spin_unlock(&sdp->sd_jindex_spin);
 821                 wait_on_bit(&jd->jd_flags, JDF_RECOVERY,
 822                             gfs2_umount_recovery_wait, TASK_UNINTERRUPTIBLE);
 823                 goto restart;
 824         }
 825         spin_unlock(&sdp->sd_jindex_spin);
 826
 827         kthread_stop(sdp->sd_quotad_process);
 828         kthread_stop(sdp->sd_logd_process);
 829
 830         if (!(sb->s_flags & MS_RDONLY)) {
 831                 error = gfs2_make_fs_ro(sdp);
 832                 if (error)
 833                         gfs2_io_error(sdp);
 834         }
 835         /*  At this point, we're through modifying the disk  */
 836
 837         /*  Release stuff  */
 838
 839         iput(sdp->sd_jindex);
 840         iput(sdp->sd_statfs_inode);
 841         iput(sdp->sd_rindex);
 842         iput(sdp->sd_quota_inode);
 843
 844         gfs2_glock_put(sdp->sd_rename_gl);
 845         gfs2_glock_put(sdp->sd_trans_gl);
 846
 847         if (!sdp->sd_args.ar_spectator) {
 848                 gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
 849                 gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
 850                 gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
 851                 gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
 852                 iput(sdp->sd_sc_inode);
 853                 iput(sdp->sd_qc_inode);
 854         }
 855
 856         gfs2_glock_dq_uninit(&sdp->sd_live_gh);
 857         gfs2_clear_rgrpd(sdp);
 858         gfs2_jindex_free(sdp);
 859         /*  Take apart glock structures and buffer lists  */
 860         gfs2_gl_hash_clear(sdp);
 861         /*  Unmount the locking protocol  */
 862         gfs2_lm_unmount(sdp);
 863
 864         /*  At this point, we're through participating in the lockspace  */
 865         gfs2_sys_fs_del(sdp);
 866 }
 867
 868 /**
 869  * gfs2_sync_fs - sync the filesystem
 870  * @sb: the superblock
 871  *
 872  * Flushes the log to disk.
 873  */
 874
 875 static int gfs2_sync_fs(struct super_block *sb, int wait)
 876 {
 877         if (wait && sb->s_fs_info)
 878                 gfs2_log_flush(sb->s_fs_info, NULL);
 879         return 0;
 880 }
 881
 882 /**
 883  * gfs2_freeze - prevent further writes to the filesystem
 884  * @sb: the VFS structure for the filesystem
 885  *
 886  */
 887
 888 static int gfs2_freeze(struct super_block *sb)
 889 {
 890         struct gfs2_sbd *sdp = sb->s_fs_info;
 891         int error;
 892
 893         if (test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
 894                 return -EINVAL;
 895
 896         for (;;) {
 897                 error = gfs2_freeze_fs(sdp);
 898                 if (!error)
 899                         break;
 900
 901                 switch (error) {
 902                 case -EBUSY:
 903                         fs_err(sdp, "waiting for recovery before freeze\n");
 904                         break;
 905
 906                 default:
 907                         fs_err(sdp, "error freezing FS: %d\n", error);
 908                         break;
 909                 }
 910
 911                 fs_err(sdp, "retrying...\n");
 912                 msleep(1000);
 913         }
 914         return 0;
 915 }
 916
 917 /**
 918  * gfs2_unfreeze - reallow writes to the filesystem
 919  * @sb: the VFS structure for the filesystem
 920  *
 921  */
 922
 923 static int gfs2_unfreeze(struct super_block *sb)
 924 {
 925         gfs2_unfreeze_fs(sb->s_fs_info);
 926         return 0;
 927 }
 928
 929 /**
 930  * statfs_fill - fill in the sg for a given RG
 931  * @rgd: the RG
 932  * @sc: the sc structure
 933  *
 934  * Returns: 0 on success, -ESTALE if the LVB is invalid
 935  */
 936
 937 static int statfs_slow_fill(struct gfs2_rgrpd *rgd,
 938                             struct gfs2_statfs_change_host *sc)
 939 {
 940         gfs2_rgrp_verify(rgd);
 941         sc->sc_total += rgd->rd_data;
 942         sc->sc_free += rgd->rd_free;
 943         sc->sc_dinodes += rgd->rd_dinodes;
 944         return 0;
 945 }
 946
 947 /**
 948  * gfs2_statfs_slow - Stat a filesystem using asynchronous locking
 949  * @sdp: the filesystem
 950  * @sc: the sc info that will be returned
 951  *
 952  * Any error (other than a signal) will cause this routine to fall back
 953  * to the synchronous version.
 954  *
 955  * FIXME: This really shouldn't busy wait like this.
 956  *
 957  * Returns: errno
 958  */
 959
 960 static int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
 961 {
 962         struct gfs2_holder ri_gh;
 963         struct gfs2_rgrpd *rgd_next;
 964         struct gfs2_holder *gha, *gh;
 965         unsigned int slots = 64;
 966         unsigned int x;
 967         int done;
 968         int error = 0, err;
 969
 970         memset(sc, 0, sizeof(struct gfs2_statfs_change_host));
 971         gha = kcalloc(slots, sizeof(struct gfs2_holder), GFP_KERNEL);
 972         if (!gha)
 973                 return -ENOMEM;
 974
 975         error = gfs2_rindex_hold(sdp, &ri_gh);
 976         if (error)
 977                 goto out;
 978
 979         rgd_next = gfs2_rgrpd_get_first(sdp);
 980
 981         for (;;) {
 982                 done = 1;
 983
 984                 for (x = 0; x < slots; x++) {
 985                         gh = gha + x;
 986
 987                         if (gh->gh_gl && gfs2_glock_poll(gh)) {
 988                                 err = gfs2_glock_wait(gh);
 989                                 if (err) {
 990                                         gfs2_holder_uninit(gh);
 991                                         error = err;
 992                                 } else {
 993                                         if (!error)
 994                                                 error = statfs_slow_fill(
 995                                                         gh->gh_gl->gl_object, sc);
 996                                         gfs2_glock_dq_uninit(gh);
 997                                 }
 998                         }
 999
1000                         if (gh->gh_gl)
1001                                 done = 0;
1002                         else if (rgd_next && !error) {
1003                                 error = gfs2_glock_nq_init(rgd_next->rd_gl,
1004                                                            LM_ST_SHARED,
1005                                                            GL_ASYNC,
1006                                                            gh);
1007                                 rgd_next = gfs2_rgrpd_get_next(rgd_next);
1008                                 done = 0;
1009                         }
1010
1011                         if (signal_pending(current))
1012                                 error = -ERESTARTSYS;
1013                 }
1014
1015                 if (done)
1016                         break;
1017
1018                 yield();
1019         }
1020
1021         gfs2_glock_dq_uninit(&ri_gh);
1022
1023 out:
1024         kfree(gha);
1025         return error;
1026 }
1027
1028 /**
1029  * gfs2_statfs_i - Do a statfs
1030  * @sdp: the filesystem
1031  * @sg: the sg structure
1032  *
1033  * Returns: errno
1034  */
1035
1036 static int gfs2_statfs_i(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
1037 {
1038         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
1039         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
1040
1041         spin_lock(&sdp->sd_statfs_spin);
1042
1043         *sc = *m_sc;
1044         sc->sc_total += l_sc->sc_total;
1045         sc->sc_free += l_sc->sc_free;
1046         sc->sc_dinodes += l_sc->sc_dinodes;
1047
1048         spin_unlock(&sdp->sd_statfs_spin);
1049
1050         if (sc->sc_free < 0)
1051                 sc->sc_free = 0;
1052         if (sc->sc_free > sc->sc_total)
1053                 sc->sc_free = sc->sc_total;
1054         if (sc->sc_dinodes < 0)
1055                 sc->sc_dinodes = 0;
1056
1057         return 0;
1058 }
1059
1060 /**
1061  * gfs2_statfs - Gather and return stats about the filesystem
1062  * @sb: The superblock
1063  * @statfsbuf: The buffer
1064  *
1065  * Returns: 0 on success or error code
1066  */
1067
1068 static int gfs2_statfs(struct dentry *dentry, struct kstatfs *buf)
1069 {
1070         struct super_block *sb = dentry->d_inode->i_sb;
1071         struct gfs2_sbd *sdp = sb->s_fs_info;
1072         struct gfs2_statfs_change_host sc;
1073         int error;
1074
1075         if (gfs2_tune_get(sdp, gt_statfs_slow))
1076                 error = gfs2_statfs_slow(sdp, &sc);
1077         else
1078                 error = gfs2_statfs_i(sdp, &sc);
1079
1080         if (error)
1081                 return error;
1082
1083         buf->f_type = GFS2_MAGIC;
1084         buf->f_bsize = sdp->sd_sb.sb_bsize;
1085         buf->f_blocks = sc.sc_total;
1086         buf->f_bfree = sc.sc_free;
1087         buf->f_bavail = sc.sc_free;
1088         buf->f_files = sc.sc_dinodes + sc.sc_free;
1089         buf->f_ffree = sc.sc_free;
1090         buf->f_namelen = GFS2_FNAMESIZE;
1091
1092         return 0;
1093 }
1094
1095 /**
1096  * gfs2_remount_fs - called when the FS is remounted
1097  * @sb:  the filesystem
1098  * @flags:  the remount flags
1099  * @data:  extra data passed in (not used right now)
1100  *
1101  * Returns: errno
1102  */
1103
1104 static int gfs2_remount_fs(struct super_block *sb, int *flags, char *data)
1105 {
1106         struct gfs2_sbd *sdp = sb->s_fs_info;
1107         struct gfs2_args args = sdp->sd_args; /* Default to current settings */
1108         struct gfs2_tune *gt = &sdp->sd_tune;
1109         int error;
1110
1111         spin_lock(&gt->gt_spin);
1112         args.ar_commit = gt->gt_logd_secs;
1113         args.ar_quota_quantum = gt->gt_quota_quantum;
1114         if (gt->gt_statfs_slow)
1115                 args.ar_statfs_quantum = 0;
1116         else
1117                 args.ar_statfs_quantum = gt->gt_statfs_quantum;
1118         spin_unlock(&gt->gt_spin);
1119         error = gfs2_mount_args(&args, data);
1120         if (error)
1121                 return error;
1122
1123         /* Not allowed to change locking details */
1124         if (strcmp(args.ar_lockproto, sdp->sd_args.ar_lockproto) ||
1125             strcmp(args.ar_locktable, sdp->sd_args.ar_locktable) ||
1126             strcmp(args.ar_hostdata, sdp->sd_args.ar_hostdata))
1127                 return -EINVAL;
1128
1129         /* Some flags must not be changed */
1130         if (args_neq(&args, &sdp->sd_args, spectator) ||
1131             args_neq(&args, &sdp->sd_args, localflocks) ||
1132             args_neq(&args, &sdp->sd_args, meta))
1133                 return -EINVAL;
1134
1135         if (sdp->sd_args.ar_spectator)
1136                 *flags |= MS_RDONLY;
1137
1138         if ((sb->s_flags ^ *flags) & MS_RDONLY) {
1139                 if (*flags & MS_RDONLY)
1140                         error = gfs2_make_fs_ro(sdp);
1141                 else
1142                         error = gfs2_make_fs_rw(sdp);
1143                 if (error)
1144                         return error;
1145         }
1146
1147         sdp->sd_args = args;
1148         if (sdp->sd_args.ar_posix_acl)
1149                 sb->s_flags |= MS_POSIXACL;
1150         else
1151                 sb->s_flags &= ~MS_POSIXACL;
1152         if (sdp->sd_args.ar_nobarrier)
1153                 set_bit(SDF_NOBARRIERS, &sdp->sd_flags);
1154         else
1155                 clear_bit(SDF_NOBARRIERS, &sdp->sd_flags);
1156         spin_lock(&gt->gt_spin);
1157         gt->gt_logd_secs = args.ar_commit;
1158         gt->gt_quota_quantum = args.ar_quota_quantum;
1159         if (args.ar_statfs_quantum) {
1160                 gt->gt_statfs_slow = 0;
1161                 gt->gt_statfs_quantum = args.ar_statfs_quantum;
1162         }
1163         else {
1164                 gt->gt_statfs_slow = 1;
1165                 gt->gt_statfs_quantum = 30;
1166         }
1167         spin_unlock(&gt->gt_spin);
1168
1169         gfs2_online_uevent(sdp);
1170         return 0;
1171 }
1172
1173 /**
1174  * gfs2_drop_inode - Drop an inode (test for remote unlink)
1175  * @inode: The inode to drop
1176  *
1177  * If we've received a callback on an iopen lock then its because a
1178  * remote node tried to deallocate the inode but failed due to this node
1179  * still having the inode open. Here we mark the link count zero
1180  * since we know that it must have reached zero if the GLF_DEMOTE flag
1181  * is set on the iopen glock. If we didn't do a disk read since the
1182  * remote node removed the final link then we might otherwise miss
1183  * this event. This check ensures that this node will deallocate the
1184  * inode's blocks, or alternatively pass the baton on to another
1185  * node for later deallocation.
1186  */
1187
1188 static int gfs2_drop_inode(struct inode *inode)
1189 {
1190         struct gfs2_inode *ip = GFS2_I(inode);
1191
1192         if (inode->i_nlink) {
1193                 struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
1194                 if (gl && test_bit(GLF_DEMOTE, &gl->gl_flags))
1195                         clear_nlink(inode);
1196         }
1197         return generic_drop_inode(inode);
1198 }
1199
1200 static int is_ancestor(const struct dentry *d1, const struct dentry *d2)
1201 {
1202         do {
1203                 if (d1 == d2)
1204                         return 1;
1205                 d1 = d1->d_parent;
1206         } while (!IS_ROOT(d1));
1207         return 0;
1208 }
1209
1210 /**
1211  * gfs2_show_options - Show mount options for /proc/mounts
1212  * @s: seq_file structure
1213  * @mnt: vfsmount
1214  *
1215  * Returns: 0 on success or error code
1216  */
1217
1218 static int gfs2_show_options(struct seq_file *s, struct vfsmount *mnt)
1219 {
1220         struct gfs2_sbd *sdp = mnt->mnt_sb->s_fs_info;
1221         struct gfs2_args *args = &sdp->sd_args;
1222         int val;
1223
1224         if (is_ancestor(mnt->mnt_root, sdp->sd_master_dir))
1225                 seq_printf(s, ",meta");
1226         if (args->ar_lockproto[0])
1227                 seq_printf(s, ",lockproto=%s", args->ar_lockproto);
1228         if (args->ar_locktable[0])
1229                 seq_printf(s, ",locktable=%s", args->ar_locktable);
1230         if (args->ar_hostdata[0])
1231                 seq_printf(s, ",hostdata=%s", args->ar_hostdata);
1232         if (args->ar_spectator)
1233                 seq_printf(s, ",spectator");
1234         if (args->ar_localflocks)
1235                 seq_printf(s, ",localflocks");
1236         if (args->ar_debug)
1237                 seq_printf(s, ",debug");
1238         if (args->ar_posix_acl)
1239                 seq_printf(s, ",acl");
1240         if (args->ar_quota != GFS2_QUOTA_DEFAULT) {
1241                 char *state;
1242                 switch (args->ar_quota) {
1243                 case GFS2_QUOTA_OFF:
1244                         state = "off";
1245                         break;
1246                 case GFS2_QUOTA_ACCOUNT:
1247                         state = "account";
1248                         break;
1249                 case GFS2_QUOTA_ON:
1250                         state = "on";
1251                         break;
1252                 default:
1253                         state = "unknown";
1254                         break;
1255                 }
1256                 seq_printf(s, ",quota=%s", state);
1257         }
1258         if (args->ar_suiddir)
1259                 seq_printf(s, ",suiddir");
1260         if (args->ar_data != GFS2_DATA_DEFAULT) {
1261                 char *state;
1262                 switch (args->ar_data) {
1263                 case GFS2_DATA_WRITEBACK:
1264                         state = "writeback";
1265                         break;
1266                 case GFS2_DATA_ORDERED:
1267                         state = "ordered";
1268                         break;
1269                 default:
1270                         state = "unknown";
1271                         break;
1272                 }
1273                 seq_printf(s, ",data=%s", state);
1274         }
1275         if (args->ar_discard)
1276                 seq_printf(s, ",discard");
1277         val = sdp->sd_tune.gt_logd_secs;
1278         if (val != 30)
1279                 seq_printf(s, ",commit=%d", val);
1280         val = sdp->sd_tune.gt_statfs_quantum;
1281         if (val != 30)
1282                 seq_printf(s, ",statfs_quantum=%d", val);
1283         val = sdp->sd_tune.gt_quota_quantum;
1284         if (val != 60)
1285                 seq_printf(s, ",quota_quantum=%d", val);
1286         if (args->ar_statfs_percent)
1287                 seq_printf(s, ",statfs_percent=%d", args->ar_statfs_percent);
1288         if (args->ar_errors != GFS2_ERRORS_DEFAULT) {
1289                 const char *state;
1290
1291                 switch (args->ar_errors) {
1292                 case GFS2_ERRORS_WITHDRAW:
1293                         state = "withdraw";
1294                         break;
1295                 case GFS2_ERRORS_PANIC:
1296                         state = "panic";
1297                         break;
1298                 default:
1299                         state = "unknown";
1300                         break;
1301                 }
1302                 seq_printf(s, ",errors=%s", state);
1303         }
1304         if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags))
1305                 seq_printf(s, ",nobarrier");
1306         if (test_bit(SDF_DEMOTE, &sdp->sd_flags))
1307                 seq_printf(s, ",demote_interface_used");
1308         return 0;
1309 }
1310
1311 /*
1312  * We have to (at the moment) hold the inodes main lock to cover
1313  * the gap between unlocking the shared lock on the iopen lock and
1314  * taking the exclusive lock. I'd rather do a shared -> exclusive
1315  * conversion on the iopen lock, but we can change that later. This
1316  * is safe, just less efficient.
1317  */
1318
1319 static void gfs2_evict_inode(struct inode *inode)
1320 {
1321         struct super_block *sb = inode->i_sb;
1322         struct gfs2_sbd *sdp = sb->s_fs_info;
1323         struct gfs2_inode *ip = GFS2_I(inode);
1324         struct gfs2_holder gh;
1325         int error;
1326
1327         if (inode->i_nlink || (sb->s_flags & MS_RDONLY))
1328                 goto out;
1329
1330         /* Must not read inode block until block type has been verified */
1331         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_SKIP, &gh);
1332         if (unlikely(error)) {
1333                 gfs2_glock_dq_uninit(&ip->i_iopen_gh);
1334                 goto out;
1335         }
1336
1337         error = gfs2_check_blk_type(sdp, ip->i_no_addr, GFS2_BLKST_UNLINKED);
1338         if (error)
1339                 goto out_truncate;
1340
1341         if (test_bit(GIF_INVALID, &ip->i_flags)) {
1342                 error = gfs2_inode_refresh(ip);
1343                 if (error)
1344                         goto out_truncate;
1345         }
1346
1347         ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
1348         gfs2_glock_dq_wait(&ip->i_iopen_gh);
1349         gfs2_holder_reinit(LM_ST_EXCLUSIVE, LM_FLAG_TRY_1CB | GL_NOCACHE, &ip->i_iopen_gh);
1350         error = gfs2_glock_nq(&ip->i_iopen_gh);
1351         if (error)
1352                 goto out_truncate;
1353
1354         if (S_ISDIR(inode->i_mode) &&
1355             (ip->i_diskflags & GFS2_DIF_EXHASH)) {
1356                 error = gfs2_dir_exhash_dealloc(ip);
1357                 if (error)
1358                         goto out_unlock;
1359         }
1360
1361         if (ip->i_eattr) {
1362                 error = gfs2_ea_dealloc(ip);
1363                 if (error)
1364                         goto out_unlock;
1365         }
1366
1367         if (!gfs2_is_stuffed(ip)) {
1368                 error = gfs2_file_dealloc(ip);
1369                 if (error)
1370                         goto out_unlock;
1371         }
1372
1373         error = gfs2_dinode_dealloc(ip);
1374         if (error)
1375                 goto out_unlock;
1376
1377 out_truncate:
1378         error = gfs2_trans_begin(sdp, 0, sdp->sd_jdesc->jd_blocks);
1379         if (error)
1380                 goto out_unlock;
1381         /* Needs to be done before glock release & also in a transaction */
1382         truncate_inode_pages(&inode->i_data, 0);
1383         gfs2_trans_end(sdp);
1384
1385 out_unlock:
1386         if (test_bit(HIF_HOLDER, &ip->i_iopen_gh.gh_iflags))
1387                 gfs2_glock_dq(&ip->i_iopen_gh);
1388         gfs2_holder_uninit(&ip->i_iopen_gh);
1389         gfs2_glock_dq_uninit(&gh);
1390         if (error && error != GLR_TRYFAILED && error != -EROFS)
1391                 fs_warn(sdp, "gfs2_evict_inode: %d\n", error);
1392 out:
1393         truncate_inode_pages(&inode->i_data, 0);
1394         end_writeback(inode);
1395
1396         ip->i_gl->gl_object = NULL;
1397         gfs2_glock_put(ip->i_gl);
1398         ip->i_gl = NULL;
1399         if (ip->i_iopen_gh.gh_gl) {
1400                 ip->i_iopen_gh.gh_gl->gl_object = NULL;
1401                 gfs2_glock_dq_uninit(&ip->i_iopen_gh);
1402         }
1403 }
1404
1405 static struct inode *gfs2_alloc_inode(struct super_block *sb)
1406 {
1407         struct gfs2_inode *ip;
1408
1409         ip = kmem_cache_alloc(gfs2_inode_cachep, GFP_KERNEL);
1410         if (ip) {
1411                 ip->i_flags = 0;
1412                 ip->i_gl = NULL;
1413         }
1414         return &ip->i_inode;
1415 }
1416
1417 static void gfs2_i_callback(struct rcu_head *head)
1418 {
1419         struct inode *inode = container_of(head, struct inode, i_rcu);
1420         INIT_LIST_HEAD(&inode->i_dentry);
1421         kmem_cache_free(gfs2_inode_cachep, inode);
1422 }
1423
1424 static void gfs2_destroy_inode(struct inode *inode)
1425 {
1426         call_rcu(&inode->i_rcu, gfs2_i_callback);
1427 }
1428
1429 const struct super_operations gfs2_super_ops = {
1430         .alloc_inode            = gfs2_alloc_inode,
1431         .destroy_inode          = gfs2_destroy_inode,
1432         .write_inode            = gfs2_write_inode,
1433         .evict_inode            = gfs2_evict_inode,
1434         .put_super              = gfs2_put_super,
1435         .sync_fs                = gfs2_sync_fs,
1436         .freeze_fs              = gfs2_freeze,
1437         .unfreeze_fs            = gfs2_unfreeze,
1438         .statfs                 = gfs2_statfs,
1439         .remount_fs             = gfs2_remount_fs,
1440         .drop_inode             = gfs2_drop_inode,
1441         .show_options           = gfs2_show_options,
1442 };
1443