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 #include <linux/backing-dev.h>
  27
  28 #include "gfs2.h"
  29 #include "incore.h"
  30 #include "bmap.h"
  31 #include "dir.h"
  32 #include "glock.h"
  33 #include "glops.h"
  34 #include "inode.h"
  35 #include "log.h"
  36 #include "meta_io.h"
  37 #include "quota.h"
  38 #include "recovery.h"
  39 #include "rgrp.h"
  40 #include "super.h"
  41 #include "trans.h"
  42 #include "util.h"
  43 #include "sys.h"
  44 #include "xattr.h"
  45
  46 #define args_neq(a1, a2, x) ((a1)->ar_##x != (a2)->ar_##x)
  47
  48 enum {
  49         Opt_lockproto,
  50         Opt_locktable,
  51         Opt_hostdata,
  52         Opt_spectator,
  53         Opt_ignore_local_fs,
  54         Opt_localflocks,
  55         Opt_localcaching,
  56         Opt_debug,
  57         Opt_nodebug,
  58         Opt_upgrade,
  59         Opt_acl,
  60         Opt_noacl,
  61         Opt_quota_off,
  62         Opt_quota_account,
  63         Opt_quota_on,
  64         Opt_quota,
  65         Opt_noquota,
  66         Opt_suiddir,
  67         Opt_nosuiddir,
  68         Opt_data_writeback,
  69         Opt_data_ordered,
  70         Opt_meta,
  71         Opt_discard,
  72         Opt_nodiscard,
  73         Opt_commit,
  74         Opt_err_withdraw,
  75         Opt_err_panic,
  76         Opt_statfs_quantum,
  77         Opt_statfs_percent,
  78         Opt_quota_quantum,
  79         Opt_barrier,
  80         Opt_nobarrier,
  81         Opt_rgrplvb,
  82         Opt_norgrplvb,
  83         Opt_error,
  84 };
  85
  86 static const match_table_t tokens = {
  87         {Opt_lockproto, "lockproto=%s"},
  88         {Opt_locktable, "locktable=%s"},
  89         {Opt_hostdata, "hostdata=%s"},
  90         {Opt_spectator, "spectator"},
  91         {Opt_spectator, "norecovery"},
  92         {Opt_ignore_local_fs, "ignore_local_fs"},
  93         {Opt_localflocks, "localflocks"},
  94         {Opt_localcaching, "localcaching"},
  95         {Opt_debug, "debug"},
  96         {Opt_nodebug, "nodebug"},
  97         {Opt_upgrade, "upgrade"},
  98         {Opt_acl, "acl"},
  99         {Opt_noacl, "noacl"},
 100         {Opt_quota_off, "quota=off"},
 101         {Opt_quota_account, "quota=account"},
 102         {Opt_quota_on, "quota=on"},
 103         {Opt_quota, "quota"},
 104         {Opt_noquota, "noquota"},
 105         {Opt_suiddir, "suiddir"},
 106         {Opt_nosuiddir, "nosuiddir"},
 107         {Opt_data_writeback, "data=writeback"},
 108         {Opt_data_ordered, "data=ordered"},
 109         {Opt_meta, "meta"},
 110         {Opt_discard, "discard"},
 111         {Opt_nodiscard, "nodiscard"},
 112         {Opt_commit, "commit=%d"},
 113         {Opt_err_withdraw, "errors=withdraw"},
 114         {Opt_err_panic, "errors=panic"},
 115         {Opt_statfs_quantum, "statfs_quantum=%d"},
 116         {Opt_statfs_percent, "statfs_percent=%d"},
 117         {Opt_quota_quantum, "quota_quantum=%d"},
 118         {Opt_barrier, "barrier"},
 119         {Opt_nobarrier, "nobarrier"},
 120         {Opt_rgrplvb, "rgrplvb"},
 121         {Opt_norgrplvb, "norgrplvb"},
 122         {Opt_error, NULL}
 123 };
 124
 125 /**
 126  * gfs2_mount_args - Parse mount options
 127  * @args: The structure into which the parsed options will be written
 128  * @options: The options to parse
 129  *
 130  * Return: errno
 131  */
 132
 133 int gfs2_mount_args(struct gfs2_args *args, char *options)
 134 {
 135         char *o;
 136         int token;
 137         substring_t tmp[MAX_OPT_ARGS];
 138         int rv;
 139
 140         /* Split the options into tokens with the "," character and
 141            process them */
 142
 143         while (1) {
 144                 o = strsep(&options, ",");
 145                 if (o == NULL)
 146                         break;
 147                 if (*o == '\0')
 148                         continue;
 149
 150                 token = match_token(o, tokens, tmp);
 151                 switch (token) {
 152                 case Opt_lockproto:
 153                         match_strlcpy(args->ar_lockproto, &tmp[0],
 154                                       GFS2_LOCKNAME_LEN);
 155                         break;
 156                 case Opt_locktable:
 157                         match_strlcpy(args->ar_locktable, &tmp[0],
 158                                       GFS2_LOCKNAME_LEN);
 159                         break;
 160                 case Opt_hostdata:
 161                         match_strlcpy(args->ar_hostdata, &tmp[0],
 162                                       GFS2_LOCKNAME_LEN);
 163                         break;
 164                 case Opt_spectator:
 165                         args->ar_spectator = 1;
 166                         break;
 167                 case Opt_ignore_local_fs:
 168                         /* Retained for backwards compat only */
 169                         break;
 170                 case Opt_localflocks:
 171                         args->ar_localflocks = 1;
 172                         break;
 173                 case Opt_localcaching:
 174                         /* Retained for backwards compat only */
 175                         break;
 176                 case Opt_debug:
 177                         if (args->ar_errors == GFS2_ERRORS_PANIC) {
 178                                 printk(KERN_WARNING "GFS2: -o debug and -o errors=panic "
 179                                        "are mutually exclusive.\n");
 180                                 return -EINVAL;
 181                         }
 182                         args->ar_debug = 1;
 183                         break;
 184                 case Opt_nodebug:
 185                         args->ar_debug = 0;
 186                         break;
 187                 case Opt_upgrade:
 188                         /* Retained for backwards compat only */
 189                         break;
 190                 case Opt_acl:
 191                         args->ar_posix_acl = 1;
 192                         break;
 193                 case Opt_noacl:
 194                         args->ar_posix_acl = 0;
 195                         break;
 196                 case Opt_quota_off:
 197                 case Opt_noquota:
 198                         args->ar_quota = GFS2_QUOTA_OFF;
 199                         break;
 200                 case Opt_quota_account:
 201                         args->ar_quota = GFS2_QUOTA_ACCOUNT;
 202                         break;
 203                 case Opt_quota_on:
 204                 case Opt_quota:
 205                         args->ar_quota = GFS2_QUOTA_ON;
 206                         break;
 207                 case Opt_suiddir:
 208                         args->ar_suiddir = 1;
 209                         break;
 210                 case Opt_nosuiddir:
 211                         args->ar_suiddir = 0;
 212                         break;
 213                 case Opt_data_writeback:
 214                         args->ar_data = GFS2_DATA_WRITEBACK;
 215                         break;
 216                 case Opt_data_ordered:
 217                         args->ar_data = GFS2_DATA_ORDERED;
 218                         break;
 219                 case Opt_meta:
 220                         args->ar_meta = 1;
 221                         break;
 222                 case Opt_discard:
 223                         args->ar_discard = 1;
 224                         break;
 225                 case Opt_nodiscard:
 226                         args->ar_discard = 0;
 227                         break;
 228                 case Opt_commit:
 229                         rv = match_int(&tmp[0], &args->ar_commit);
 230                         if (rv || args->ar_commit <= 0) {
 231                                 printk(KERN_WARNING "GFS2: commit mount option requires a positive numeric argument\n");
 232                                 return rv ? rv : -EINVAL;
 233                         }
 234                         break;
 235                 case Opt_statfs_quantum:
 236                         rv = match_int(&tmp[0], &args->ar_statfs_quantum);
 237                         if (rv || args->ar_statfs_quantum < 0) {
 238                                 printk(KERN_WARNING "GFS2: statfs_quantum mount option requires a non-negative numeric argument\n");
 239                                 return rv ? rv : -EINVAL;
 240                         }
 241                         break;
 242                 case Opt_quota_quantum:
 243                         rv = match_int(&tmp[0], &args->ar_quota_quantum);
 244                         if (rv || args->ar_quota_quantum <= 0) {
 245                                 printk(KERN_WARNING "GFS2: quota_quantum mount option requires a positive numeric argument\n");
 246                                 return rv ? rv : -EINVAL;
 247                         }
 248                         break;
 249                 case Opt_statfs_percent:
 250                         rv = match_int(&tmp[0], &args->ar_statfs_percent);
 251                         if (rv || args->ar_statfs_percent < 0 ||
 252                             args->ar_statfs_percent > 100) {
 253                                 printk(KERN_WARNING "statfs_percent mount option requires a numeric argument between 0 and 100\n");
 254                                 return rv ? rv : -EINVAL;
 255                         }
 256                         break;
 257                 case Opt_err_withdraw:
 258                         args->ar_errors = GFS2_ERRORS_WITHDRAW;
 259                         break;
 260                 case Opt_err_panic:
 261                         if (args->ar_debug) {
 262                                 printk(KERN_WARNING "GFS2: -o debug and -o errors=panic "
 263                                         "are mutually exclusive.\n");
 264                                 return -EINVAL;
 265                         }
 266                         args->ar_errors = GFS2_ERRORS_PANIC;
 267                         break;
 268                 case Opt_barrier:
 269                         args->ar_nobarrier = 0;
 270                         break;
 271                 case Opt_nobarrier:
 272                         args->ar_nobarrier = 1;
 273                         break;
 274                 case Opt_rgrplvb:
 275                         args->ar_rgrplvb = 1;
 276                         break;
 277                 case Opt_norgrplvb:
 278                         args->ar_rgrplvb = 0;
 279                         break;
 280                 case Opt_error:
 281                 default:
 282                         printk(KERN_WARNING "GFS2: invalid mount option: %s\n", o);
 283                         return -EINVAL;
 284                 }
 285         }
 286
 287         return 0;
 288 }
 289
 290 /**
 291  * gfs2_jindex_free - Clear all the journal index information
 292  * @sdp: The GFS2 superblock
 293  *
 294  */
 295
 296 void gfs2_jindex_free(struct gfs2_sbd *sdp)
 297 {
 298         struct list_head list, *head;
 299         struct gfs2_jdesc *jd;
 300         struct gfs2_journal_extent *jext;
 301
 302         spin_lock(&sdp->sd_jindex_spin);
 303         list_add(&list, &sdp->sd_jindex_list);
 304         list_del_init(&sdp->sd_jindex_list);
 305         sdp->sd_journals = 0;
 306         spin_unlock(&sdp->sd_jindex_spin);
 307
 308         while (!list_empty(&list)) {
 309                 jd = list_entry(list.next, struct gfs2_jdesc, jd_list);
 310                 head = &jd->extent_list;
 311                 while (!list_empty(head)) {
 312                         jext = list_entry(head->next,
 313                                           struct gfs2_journal_extent,
 314                                           extent_list);
 315                         list_del(&jext->extent_list);
 316                         kfree(jext);
 317                 }
 318                 list_del(&jd->jd_list);
 319                 iput(jd->jd_inode);
 320                 kfree(jd);
 321         }
 322 }
 323
 324 static struct gfs2_jdesc *jdesc_find_i(struct list_head *head, unsigned int jid)
 325 {
 326         struct gfs2_jdesc *jd;
 327         int found = 0;
 328
 329         list_for_each_entry(jd, head, jd_list) {
 330                 if (jd->jd_jid == jid) {
 331                         found = 1;
 332                         break;
 333                 }
 334         }
 335
 336         if (!found)
 337                 jd = NULL;
 338
 339         return jd;
 340 }
 341
 342 struct gfs2_jdesc *gfs2_jdesc_find(struct gfs2_sbd *sdp, unsigned int jid)
 343 {
 344         struct gfs2_jdesc *jd;
 345
 346         spin_lock(&sdp->sd_jindex_spin);
 347         jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
 348         spin_unlock(&sdp->sd_jindex_spin);
 349
 350         return jd;
 351 }
 352
 353 int gfs2_jdesc_check(struct gfs2_jdesc *jd)
 354 {
 355         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
 356         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 357         u64 size = i_size_read(jd->jd_inode);
 358
 359         if (gfs2_check_internal_file_size(jd->jd_inode, 8 << 20, 1 << 30))
 360                 return -EIO;
 361
 362         jd->jd_blocks = size >> sdp->sd_sb.sb_bsize_shift;
 363
 364         if (gfs2_write_alloc_required(ip, 0, size)) {
 365                 gfs2_consist_inode(ip);
 366                 return -EIO;
 367         }
 368
 369         return 0;
 370 }
 371
 372 /**
 373  * gfs2_make_fs_rw - Turn a Read-Only FS into a Read-Write one
 374  * @sdp: the filesystem
 375  *
 376  * Returns: errno
 377  */
 378
 379 int gfs2_make_fs_rw(struct gfs2_sbd *sdp)
 380 {
 381         struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
 382         struct gfs2_glock *j_gl = ip->i_gl;
 383         struct gfs2_holder t_gh;
 384         struct gfs2_log_header_host head;
 385         int error;
 386
 387         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED, 0, &t_gh);
 388         if (error)
 389                 return error;
 390
 391         j_gl->gl_ops->go_inval(j_gl, DIO_METADATA);
 392
 393         error = gfs2_find_jhead(sdp->sd_jdesc, &head);
 394         if (error)
 395                 goto fail;
 396
 397         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 398                 gfs2_consist(sdp);
 399                 error = -EIO;
 400                 goto fail;
 401         }
 402
 403         /*  Initialize some head of the log stuff  */
 404         sdp->sd_log_sequence = head.lh_sequence + 1;
 405         gfs2_log_pointers_init(sdp, head.lh_blkno);
 406
 407         error = gfs2_quota_init(sdp);
 408         if (error)
 409                 goto fail;
 410
 411         set_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 412
 413         gfs2_glock_dq_uninit(&t_gh);
 414
 415         return 0;
 416
 417 fail:
 418         t_gh.gh_flags |= GL_NOCACHE;
 419         gfs2_glock_dq_uninit(&t_gh);
 420
 421         return error;
 422 }
 423
 424 void gfs2_statfs_change_in(struct gfs2_statfs_change_host *sc, const void *buf)
 425 {
 426         const struct gfs2_statfs_change *str = buf;
 427
 428         sc->sc_total = be64_to_cpu(str->sc_total);
 429         sc->sc_free = be64_to_cpu(str->sc_free);
 430         sc->sc_dinodes = be64_to_cpu(str->sc_dinodes);
 431 }
 432
 433 static void gfs2_statfs_change_out(const struct gfs2_statfs_change_host *sc, void *buf)
 434 {
 435         struct gfs2_statfs_change *str = buf;
 436
 437         str->sc_total = cpu_to_be64(sc->sc_total);
 438         str->sc_free = cpu_to_be64(sc->sc_free);
 439         str->sc_dinodes = cpu_to_be64(sc->sc_dinodes);
 440 }
 441
 442 int gfs2_statfs_init(struct gfs2_sbd *sdp)
 443 {
 444         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 445         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 446         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 447         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 448         struct buffer_head *m_bh, *l_bh;
 449         struct gfs2_holder gh;
 450         int error;
 451
 452         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 453                                    &gh);
 454         if (error)
 455                 return error;
 456
 457         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 458         if (error)
 459                 goto out;
 460
 461         if (sdp->sd_args.ar_spectator) {
 462                 spin_lock(&sdp->sd_statfs_spin);
 463                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 464                                       sizeof(struct gfs2_dinode));
 465                 spin_unlock(&sdp->sd_statfs_spin);
 466         } else {
 467                 error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 468                 if (error)
 469                         goto out_m_bh;
 470
 471                 spin_lock(&sdp->sd_statfs_spin);
 472                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 473                                       sizeof(struct gfs2_dinode));
 474                 gfs2_statfs_change_in(l_sc, l_bh->b_data +
 475                                       sizeof(struct gfs2_dinode));
 476                 spin_unlock(&sdp->sd_statfs_spin);
 477
 478                 brelse(l_bh);
 479         }
 480
 481 out_m_bh:
 482         brelse(m_bh);
 483 out:
 484         gfs2_glock_dq_uninit(&gh);
 485         return 0;
 486 }
 487
 488 void gfs2_statfs_change(struct gfs2_sbd *sdp, s64 total, s64 free,
 489                         s64 dinodes)
 490 {
 491         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 492         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 493         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 494         struct buffer_head *l_bh;
 495         s64 x, y;
 496         int need_sync = 0;
 497         int error;
 498
 499         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 500         if (error)
 501                 return;
 502
 503         gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
 504
 505         spin_lock(&sdp->sd_statfs_spin);
 506         l_sc->sc_total += total;
 507         l_sc->sc_free += free;
 508         l_sc->sc_dinodes += dinodes;
 509         gfs2_statfs_change_out(l_sc, l_bh->b_data + sizeof(struct gfs2_dinode));
 510         if (sdp->sd_args.ar_statfs_percent) {
 511                 x = 100 * l_sc->sc_free;
 512                 y = m_sc->sc_free * sdp->sd_args.ar_statfs_percent;
 513                 if (x >= y || x <= -y)
 514                         need_sync = 1;
 515         }
 516         spin_unlock(&sdp->sd_statfs_spin);
 517
 518         brelse(l_bh);
 519         if (need_sync)
 520                 gfs2_wake_up_statfs(sdp);
 521 }
 522
 523 void update_statfs(struct gfs2_sbd *sdp, struct buffer_head *m_bh,
 524                    struct buffer_head *l_bh)
 525 {
 526         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 527         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 528         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 529         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 530
 531         gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
 532
 533         spin_lock(&sdp->sd_statfs_spin);
 534         m_sc->sc_total += l_sc->sc_total;
 535         m_sc->sc_free += l_sc->sc_free;
 536         m_sc->sc_dinodes += l_sc->sc_dinodes;
 537         memset(l_sc, 0, sizeof(struct gfs2_statfs_change));
 538         memset(l_bh->b_data + sizeof(struct gfs2_dinode),
 539                0, sizeof(struct gfs2_statfs_change));
 540         spin_unlock(&sdp->sd_statfs_spin);
 541
 542         gfs2_trans_add_bh(m_ip->i_gl, m_bh, 1);
 543         gfs2_statfs_change_out(m_sc, m_bh->b_data + sizeof(struct gfs2_dinode));
 544 }
 545
 546 int gfs2_statfs_sync(struct super_block *sb, int type)
 547 {
 548         struct gfs2_sbd *sdp = sb->s_fs_info;
 549         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 550         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 551         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 552         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 553         struct gfs2_holder gh;
 554         struct buffer_head *m_bh, *l_bh;
 555         int error;
 556
 557         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 558                                    &gh);
 559         if (error)
 560                 return error;
 561
 562         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 563         if (error)
 564                 goto out;
 565
 566         spin_lock(&sdp->sd_statfs_spin);
 567         gfs2_statfs_change_in(m_sc, m_bh->b_data +
 568                               sizeof(struct gfs2_dinode));
 569         if (!l_sc->sc_total && !l_sc->sc_free && !l_sc->sc_dinodes) {
 570                 spin_unlock(&sdp->sd_statfs_spin);
 571                 goto out_bh;
 572         }
 573         spin_unlock(&sdp->sd_statfs_spin);
 574
 575         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 576         if (error)
 577                 goto out_bh;
 578
 579         error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
 580         if (error)
 581                 goto out_bh2;
 582
 583         update_statfs(sdp, m_bh, l_bh);
 584         sdp->sd_statfs_force_sync = 0;
 585
 586         gfs2_trans_end(sdp);
 587
 588 out_bh2:
 589         brelse(l_bh);
 590 out_bh:
 591         brelse(m_bh);
 592 out:
 593         gfs2_glock_dq_uninit(&gh);
 594         return error;
 595 }
 596
 597 struct lfcc {
 598         struct list_head list;
 599         struct gfs2_holder gh;
 600 };
 601
 602 /**
 603  * gfs2_lock_fs_check_clean - Stop all writes to the FS and check that all
 604  *                            journals are clean
 605  * @sdp: the file system
 606  * @state: the state to put the transaction lock into
 607  * @t_gh: the hold on the transaction lock
 608  *
 609  * Returns: errno
 610  */
 611
 612 static int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp,
 613                                     struct gfs2_holder *t_gh)
 614 {
 615         struct gfs2_inode *ip;
 616         struct gfs2_jdesc *jd;
 617         struct lfcc *lfcc;
 618         LIST_HEAD(list);
 619         struct gfs2_log_header_host lh;
 620         int error;
 621
 622         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 623                 lfcc = kmalloc(sizeof(struct lfcc), GFP_KERNEL);
 624                 if (!lfcc) {
 625                         error = -ENOMEM;
 626                         goto out;
 627                 }
 628                 ip = GFS2_I(jd->jd_inode);
 629                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &lfcc->gh);
 630                 if (error) {
 631                         kfree(lfcc);
 632                         goto out;
 633                 }
 634                 list_add(&lfcc->list, &list);
 635         }
 636
 637         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_DEFERRED,
 638                                    GL_NOCACHE, t_gh);
 639
 640         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 641                 error = gfs2_jdesc_check(jd);
 642                 if (error)
 643                         break;
 644                 error = gfs2_find_jhead(jd, &lh);
 645                 if (error)
 646                         break;
 647                 if (!(lh.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 648                         error = -EBUSY;
 649                         break;
 650                 }
 651         }
 652
 653         if (error)
 654                 gfs2_glock_dq_uninit(t_gh);
 655
 656 out:
 657         while (!list_empty(&list)) {
 658                 lfcc = list_entry(list.next, struct lfcc, list);
 659                 list_del(&lfcc->list);
 660                 gfs2_glock_dq_uninit(&lfcc->gh);
 661                 kfree(lfcc);
 662         }
 663         return error;
 664 }
 665
 666 /**
 667  * gfs2_freeze_fs - freezes the file system
 668  * @sdp: the file system
 669  *
 670  * This function flushes data and meta data for all machines by
 671  * acquiring the transaction log exclusively.  All journals are
 672  * ensured to be in a clean state as well.
 673  *
 674  * Returns: errno
 675  */
 676
 677 int gfs2_freeze_fs(struct gfs2_sbd *sdp)
 678 {
 679         int error = 0;
 680
 681         mutex_lock(&sdp->sd_freeze_lock);
 682
 683         if (!sdp->sd_freeze_count++) {
 684                 error = gfs2_lock_fs_check_clean(sdp, &sdp->sd_freeze_gh);
 685                 if (error)
 686                         sdp->sd_freeze_count--;
 687         }
 688
 689         mutex_unlock(&sdp->sd_freeze_lock);
 690
 691         return error;
 692 }
 693
 694 /**
 695  * gfs2_unfreeze_fs - unfreezes the file system
 696  * @sdp: the file system
 697  *
 698  * This function allows the file system to proceed by unlocking
 699  * the exclusively held transaction lock.  Other GFS2 nodes are
 700  * now free to acquire the lock shared and go on with their lives.
 701  *
 702  */
 703
 704 void gfs2_unfreeze_fs(struct gfs2_sbd *sdp)
 705 {
 706         mutex_lock(&sdp->sd_freeze_lock);
 707
 708         if (sdp->sd_freeze_count && !--sdp->sd_freeze_count)
 709                 gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
 710
 711         mutex_unlock(&sdp->sd_freeze_lock);
 712 }
 713
 714 void gfs2_dinode_out(const struct gfs2_inode *ip, void *buf)
 715 {
 716         struct gfs2_dinode *str = buf;
 717
 718         str->di_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
 719         str->di_header.mh_type = cpu_to_be32(GFS2_METATYPE_DI);
 720         str->di_header.mh_format = cpu_to_be32(GFS2_FORMAT_DI);
 721         str->di_num.no_addr = cpu_to_be64(ip->i_no_addr);
 722         str->di_num.no_formal_ino = cpu_to_be64(ip->i_no_formal_ino);
 723         str->di_mode = cpu_to_be32(ip->i_inode.i_mode);
 724         str->di_uid = cpu_to_be32(ip->i_inode.i_uid);
 725         str->di_gid = cpu_to_be32(ip->i_inode.i_gid);
 726         str->di_nlink = cpu_to_be32(ip->i_inode.i_nlink);
 727         str->di_size = cpu_to_be64(i_size_read(&ip->i_inode));
 728         str->di_blocks = cpu_to_be64(gfs2_get_inode_blocks(&ip->i_inode));
 729         str->di_atime = cpu_to_be64(ip->i_inode.i_atime.tv_sec);
 730         str->di_mtime = cpu_to_be64(ip->i_inode.i_mtime.tv_sec);
 731         str->di_ctime = cpu_to_be64(ip->i_inode.i_ctime.tv_sec);
 732
 733         str->di_goal_meta = cpu_to_be64(ip->i_goal);
 734         str->di_goal_data = cpu_to_be64(ip->i_goal);
 735         str->di_generation = cpu_to_be64(ip->i_generation);
 736
 737         str->di_flags = cpu_to_be32(ip->i_diskflags);
 738         str->di_height = cpu_to_be16(ip->i_height);
 739         str->di_payload_format = cpu_to_be32(S_ISDIR(ip->i_inode.i_mode) &&
 740                                              !(ip->i_diskflags & GFS2_DIF_EXHASH) ?
 741                                              GFS2_FORMAT_DE : 0);
 742         str->di_depth = cpu_to_be16(ip->i_depth);
 743         str->di_entries = cpu_to_be32(ip->i_entries);
 744
 745         str->di_eattr = cpu_to_be64(ip->i_eattr);
 746         str->di_atime_nsec = cpu_to_be32(ip->i_inode.i_atime.tv_nsec);
 747         str->di_mtime_nsec = cpu_to_be32(ip->i_inode.i_mtime.tv_nsec);
 748         str->di_ctime_nsec = cpu_to_be32(ip->i_inode.i_ctime.tv_nsec);
 749 }
 750
 751 /**
 752  * gfs2_write_inode - Make sure the inode is stable on the disk
 753  * @inode: The inode
 754  * @wbc: The writeback control structure
 755  *
 756  * Returns: errno
 757  */
 758
 759 static int gfs2_write_inode(struct inode *inode, struct writeback_control *wbc)
 760 {
 761         struct gfs2_inode *ip = GFS2_I(inode);
 762         struct gfs2_sbd *sdp = GFS2_SB(inode);
 763         struct address_space *metamapping = gfs2_glock2aspace(ip->i_gl);
 764         struct backing_dev_info *bdi = metamapping->backing_dev_info;
 765         int ret = 0;
 766
 767         if (wbc->sync_mode == WB_SYNC_ALL)
 768                 gfs2_log_flush(GFS2_SB(inode), ip->i_gl);
 769         if (bdi->dirty_exceeded)
 770                 gfs2_ail1_flush(sdp, wbc);
 771         else
 772                 filemap_fdatawrite(metamapping);
 773         if (wbc->sync_mode == WB_SYNC_ALL)
 774                 ret = filemap_fdatawait(metamapping);
 775         if (ret)
 776                 mark_inode_dirty_sync(inode);
 777         return ret;
 778 }
 779
 780 /**
 781  * gfs2_dirty_inode - check for atime updates
 782  * @inode: The inode in question
 783  * @flags: The type of dirty
 784  *
 785  * Unfortunately it can be called under any combination of inode
 786  * glock and transaction lock, so we have to check carefully.
 787  *
 788  * At the moment this deals only with atime - it should be possible
 789  * to expand that role in future, once a review of the locking has
 790  * been carried out.
 791  */
 792
 793 static void gfs2_dirty_inode(struct inode *inode, int flags)
 794 {
 795         struct gfs2_inode *ip = GFS2_I(inode);
 796         struct gfs2_sbd *sdp = GFS2_SB(inode);
 797         struct buffer_head *bh;
 798         struct gfs2_holder gh;
 799         int need_unlock = 0;
 800         int need_endtrans = 0;
 801         int ret;
 802
 803         if (!(flags & (I_DIRTY_DATASYNC|I_DIRTY_SYNC)))
 804                 return;
 805
 806         if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
 807                 ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
 808                 if (ret) {
 809                         fs_err(sdp, "dirty_inode: glock %d\n", ret);
 810                         return;
 811                 }
 812                 need_unlock = 1;
 813         } else if (WARN_ON_ONCE(ip->i_gl->gl_state != LM_ST_EXCLUSIVE))
 814                 return;
 815
 816         if (current->journal_info == NULL) {
 817                 ret = gfs2_trans_begin(sdp, RES_DINODE, 0);
 818                 if (ret) {
 819                         fs_err(sdp, "dirty_inode: gfs2_trans_begin %d\n", ret);
 820                         goto out;
 821                 }
 822                 need_endtrans = 1;
 823         }
 824
 825         ret = gfs2_meta_inode_buffer(ip, &bh);
 826         if (ret == 0) {
 827                 gfs2_trans_add_bh(ip->i_gl, bh, 1);
 828                 gfs2_dinode_out(ip, bh->b_data);
 829                 brelse(bh);
 830         }
 831
 832         if (need_endtrans)
 833                 gfs2_trans_end(sdp);
 834 out:
 835         if (need_unlock)
 836                 gfs2_glock_dq_uninit(&gh);
 837 }
 838
 839 /**
 840  * gfs2_make_fs_ro - Turn a Read-Write FS into a Read-Only one
 841  * @sdp: the filesystem
 842  *
 843  * Returns: errno
 844  */
 845
 846 static int gfs2_make_fs_ro(struct gfs2_sbd *sdp)
 847 {
 848         struct gfs2_holder t_gh;
 849         int error;
 850
 851         flush_workqueue(gfs2_delete_workqueue);
 852         gfs2_quota_sync(sdp->sd_vfs, 0);
 853         gfs2_statfs_sync(sdp->sd_vfs, 0);
 854
 855         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED, GL_NOCACHE,
 856                                    &t_gh);
 857         if (error && !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
 858                 return error;
 859
 860         gfs2_meta_syncfs(sdp);
 861         gfs2_log_shutdown(sdp);
 862
 863         clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 864
 865         if (t_gh.gh_gl)
 866                 gfs2_glock_dq_uninit(&t_gh);
 867
 868         gfs2_quota_cleanup(sdp);
 869
 870         return error;
 871 }
 872
 873 static int gfs2_umount_recovery_wait(void *word)
 874 {
 875         schedule();
 876         return 0;
 877 }
 878
 879 /**
 880  * gfs2_put_super - Unmount the filesystem
 881  * @sb: The VFS superblock
 882  *
 883  */
 884
 885 static void gfs2_put_super(struct super_block *sb)
 886 {
 887         struct gfs2_sbd *sdp = sb->s_fs_info;
 888         int error;
 889         struct gfs2_jdesc *jd;
 890
 891         /*  Unfreeze the filesystem, if we need to  */
 892
 893         mutex_lock(&sdp->sd_freeze_lock);
 894         if (sdp->sd_freeze_count)
 895                 gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
 896         mutex_unlock(&sdp->sd_freeze_lock);
 897
 898         /* No more recovery requests */
 899         set_bit(SDF_NORECOVERY, &sdp->sd_flags);
 900         smp_mb();
 901
 902         /* Wait on outstanding recovery */
 903 restart:
 904         spin_lock(&sdp->sd_jindex_spin);
 905         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 906                 if (!test_bit(JDF_RECOVERY, &jd->jd_flags))
 907                         continue;
 908                 spin_unlock(&sdp->sd_jindex_spin);
 909                 wait_on_bit(&jd->jd_flags, JDF_RECOVERY,
 910                             gfs2_umount_recovery_wait, TASK_UNINTERRUPTIBLE);
 911                 goto restart;
 912         }
 913         spin_unlock(&sdp->sd_jindex_spin);
 914
 915         kthread_stop(sdp->sd_quotad_process);
 916         kthread_stop(sdp->sd_logd_process);
 917
 918         if (!(sb->s_flags & MS_RDONLY)) {
 919                 error = gfs2_make_fs_ro(sdp);
 920                 if (error)
 921                         gfs2_io_error(sdp);
 922         }
 923         /*  At this point, we're through modifying the disk  */
 924
 925         /*  Release stuff  */
 926
 927         iput(sdp->sd_jindex);
 928         iput(sdp->sd_statfs_inode);
 929         iput(sdp->sd_rindex);
 930         iput(sdp->sd_quota_inode);
 931
 932         gfs2_glock_put(sdp->sd_rename_gl);
 933         gfs2_glock_put(sdp->sd_trans_gl);
 934
 935         if (!sdp->sd_args.ar_spectator) {
 936                 gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
 937                 gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
 938                 gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
 939                 gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
 940                 iput(sdp->sd_sc_inode);
 941                 iput(sdp->sd_qc_inode);
 942         }
 943
 944         gfs2_glock_dq_uninit(&sdp->sd_live_gh);
 945         gfs2_clear_rgrpd(sdp);
 946         gfs2_jindex_free(sdp);
 947         /*  Take apart glock structures and buffer lists  */
 948         gfs2_gl_hash_clear(sdp);
 949         /*  Unmount the locking protocol  */
 950         gfs2_lm_unmount(sdp);
 951
 952         /*  At this point, we're through participating in the lockspace  */
 953         gfs2_sys_fs_del(sdp);
 954 }
 955
 956 /**
 957  * gfs2_sync_fs - sync the filesystem
 958  * @sb: the superblock
 959  *
 960  * Flushes the log to disk.
 961  */
 962
 963 static int gfs2_sync_fs(struct super_block *sb, int wait)
 964 {
 965         struct gfs2_sbd *sdp = sb->s_fs_info;
 966
 967         gfs2_quota_sync(sb, -1);
 968         if (wait && sdp)
 969                 gfs2_log_flush(sdp, NULL);
 970         return 0;
 971 }
 972
 973 /**
 974  * gfs2_freeze - prevent further writes to the filesystem
 975  * @sb: the VFS structure for the filesystem
 976  *
 977  */
 978
 979 static int gfs2_freeze(struct super_block *sb)
 980 {
 981         struct gfs2_sbd *sdp = sb->s_fs_info;
 982         int error;
 983
 984         if (test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
 985                 return -EINVAL;
 986
 987         for (;;) {
 988                 error = gfs2_freeze_fs(sdp);
 989                 if (!error)
 990                         break;
 991
 992                 switch (error) {
 993                 case -EBUSY:
 994                         fs_err(sdp, "waiting for recovery before freeze\n");
 995                         break;
 996
 997                 default:
 998                         fs_err(sdp, "error freezing FS: %d\n", error);
 999                         break;
1000                 }
1001
1002                 fs_err(sdp, "retrying...\n");
1003                 msleep(1000);
1004         }
1005         return 0;
1006 }
1007
1008 /**
1009  * gfs2_unfreeze - reallow writes to the filesystem
1010  * @sb: the VFS structure for the filesystem
1011  *
1012  */
1013
1014 static int gfs2_unfreeze(struct super_block *sb)
1015 {
1016         gfs2_unfreeze_fs(sb->s_fs_info);
1017         return 0;
1018 }
1019
1020 /**
1021  * statfs_fill - fill in the sg for a given RG
1022  * @rgd: the RG
1023  * @sc: the sc structure
1024  *
1025  * Returns: 0 on success, -ESTALE if the LVB is invalid
1026  */
1027
1028 static int statfs_slow_fill(struct gfs2_rgrpd *rgd,
1029                             struct gfs2_statfs_change_host *sc)
1030 {
1031         gfs2_rgrp_verify(rgd);
1032         sc->sc_total += rgd->rd_data;
1033         sc->sc_free += rgd->rd_free;
1034         sc->sc_dinodes += rgd->rd_dinodes;
1035         return 0;
1036 }
1037
1038 /**
1039  * gfs2_statfs_slow - Stat a filesystem using asynchronous locking
1040  * @sdp: the filesystem
1041  * @sc: the sc info that will be returned
1042  *
1043  * Any error (other than a signal) will cause this routine to fall back
1044  * to the synchronous version.
1045  *
1046  * FIXME: This really shouldn't busy wait like this.
1047  *
1048  * Returns: errno
1049  */
1050
1051 static int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
1052 {
1053         struct gfs2_rgrpd *rgd_next;
1054         struct gfs2_holder *gha, *gh;
1055         unsigned int slots = 64;
1056         unsigned int x;
1057         int done;
1058         int error = 0, err;
1059
1060         memset(sc, 0, sizeof(struct gfs2_statfs_change_host));
1061         gha = kcalloc(slots, sizeof(struct gfs2_holder), GFP_KERNEL);
1062         if (!gha)
1063                 return -ENOMEM;
1064
1065         rgd_next = gfs2_rgrpd_get_first(sdp);
1066
1067         for (;;) {
1068                 done = 1;
1069
1070                 for (x = 0; x < slots; x++) {
1071                         gh = gha + x;
1072
1073                         if (gh->gh_gl && gfs2_glock_poll(gh)) {
1074                                 err = gfs2_glock_wait(gh);
1075                                 if (err) {
1076                                         gfs2_holder_uninit(gh);
1077                                         error = err;
1078                                 } else {
1079                                         if (!error)
1080                                                 error = statfs_slow_fill(
1081                                                         gh->gh_gl->gl_object, sc);
1082                                         gfs2_glock_dq_uninit(gh);
1083                                 }
1084                         }
1085
1086                         if (gh->gh_gl)
1087                                 done = 0;
1088                         else if (rgd_next && !error) {
1089                                 error = gfs2_glock_nq_init(rgd_next->rd_gl,
1090                                                            LM_ST_SHARED,
1091                                                            GL_ASYNC,
1092                                                            gh);
1093                                 rgd_next = gfs2_rgrpd_get_next(rgd_next);
1094                                 done = 0;
1095                         }
1096
1097                         if (signal_pending(current))
1098                                 error = -ERESTARTSYS;
1099                 }
1100
1101                 if (done)
1102                         break;
1103
1104                 yield();
1105         }
1106
1107         kfree(gha);
1108         return error;
1109 }
1110
1111 /**
1112  * gfs2_statfs_i - Do a statfs
1113  * @sdp: the filesystem
1114  * @sg: the sg structure
1115  *
1116  * Returns: errno
1117  */
1118
1119 static int gfs2_statfs_i(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
1120 {
1121         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
1122         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
1123
1124         spin_lock(&sdp->sd_statfs_spin);
1125
1126         *sc = *m_sc;
1127         sc->sc_total += l_sc->sc_total;
1128         sc->sc_free += l_sc->sc_free;
1129         sc->sc_dinodes += l_sc->sc_dinodes;
1130
1131         spin_unlock(&sdp->sd_statfs_spin);
1132
1133         if (sc->sc_free < 0)
1134                 sc->sc_free = 0;
1135         if (sc->sc_free > sc->sc_total)
1136                 sc->sc_free = sc->sc_total;
1137         if (sc->sc_dinodes < 0)
1138                 sc->sc_dinodes = 0;
1139
1140         return 0;
1141 }
1142
1143 /**
1144  * gfs2_statfs - Gather and return stats about the filesystem
1145  * @sb: The superblock
1146  * @statfsbuf: The buffer
1147  *
1148  * Returns: 0 on success or error code
1149  */
1150
1151 static int gfs2_statfs(struct dentry *dentry, struct kstatfs *buf)
1152 {
1153         struct super_block *sb = dentry->d_inode->i_sb;
1154         struct gfs2_sbd *sdp = sb->s_fs_info;
1155         struct gfs2_statfs_change_host sc;
1156         int error;
1157
1158         error = gfs2_rindex_update(sdp);
1159         if (error)
1160                 return error;
1161
1162         if (gfs2_tune_get(sdp, gt_statfs_slow))
1163                 error = gfs2_statfs_slow(sdp, &sc);
1164         else
1165                 error = gfs2_statfs_i(sdp, &sc);
1166
1167         if (error)
1168                 return error;
1169
1170         buf->f_type = GFS2_MAGIC;
1171         buf->f_bsize = sdp->sd_sb.sb_bsize;
1172         buf->f_blocks = sc.sc_total;
1173         buf->f_bfree = sc.sc_free;
1174         buf->f_bavail = sc.sc_free;
1175         buf->f_files = sc.sc_dinodes + sc.sc_free;
1176         buf->f_ffree = sc.sc_free;
1177         buf->f_namelen = GFS2_FNAMESIZE;
1178
1179         return 0;
1180 }
1181
1182 /**
1183  * gfs2_remount_fs - called when the FS is remounted
1184  * @sb:  the filesystem
1185  * @flags:  the remount flags
1186  * @data:  extra data passed in (not used right now)
1187  *
1188  * Returns: errno
1189  */
1190
1191 static int gfs2_remount_fs(struct super_block *sb, int *flags, char *data)
1192 {
1193         struct gfs2_sbd *sdp = sb->s_fs_info;
1194         struct gfs2_args args = sdp->sd_args; /* Default to current settings */
1195         struct gfs2_tune *gt = &sdp->sd_tune;
1196         int error;
1197
1198         spin_lock(&gt->gt_spin);
1199         args.ar_commit = gt->gt_logd_secs;
1200         args.ar_quota_quantum = gt->gt_quota_quantum;
1201         if (gt->gt_statfs_slow)
1202                 args.ar_statfs_quantum = 0;
1203         else
1204                 args.ar_statfs_quantum = gt->gt_statfs_quantum;
1205         spin_unlock(&gt->gt_spin);
1206         error = gfs2_mount_args(&args, data);
1207         if (error)
1208                 return error;
1209
1210         /* Not allowed to change locking details */
1211         if (strcmp(args.ar_lockproto, sdp->sd_args.ar_lockproto) ||
1212             strcmp(args.ar_locktable, sdp->sd_args.ar_locktable) ||
1213             strcmp(args.ar_hostdata, sdp->sd_args.ar_hostdata))
1214                 return -EINVAL;
1215
1216         /* Some flags must not be changed */
1217         if (args_neq(&args, &sdp->sd_args, spectator) ||
1218             args_neq(&args, &sdp->sd_args, localflocks) ||
1219             args_neq(&args, &sdp->sd_args, meta))
1220                 return -EINVAL;
1221
1222         if (sdp->sd_args.ar_spectator)
1223                 *flags |= MS_RDONLY;
1224
1225         if ((sb->s_flags ^ *flags) & MS_RDONLY) {
1226                 if (*flags & MS_RDONLY)
1227                         error = gfs2_make_fs_ro(sdp);
1228                 else
1229                         error = gfs2_make_fs_rw(sdp);
1230                 if (error)
1231                         return error;
1232         }
1233
1234         sdp->sd_args = args;
1235         if (sdp->sd_args.ar_posix_acl)
1236                 sb->s_flags |= MS_POSIXACL;
1237         else
1238                 sb->s_flags &= ~MS_POSIXACL;
1239         if (sdp->sd_args.ar_nobarrier)
1240                 set_bit(SDF_NOBARRIERS, &sdp->sd_flags);
1241         else
1242                 clear_bit(SDF_NOBARRIERS, &sdp->sd_flags);
1243         spin_lock(&gt->gt_spin);
1244         gt->gt_logd_secs = args.ar_commit;
1245         gt->gt_quota_quantum = args.ar_quota_quantum;
1246         if (args.ar_statfs_quantum) {
1247                 gt->gt_statfs_slow = 0;
1248                 gt->gt_statfs_quantum = args.ar_statfs_quantum;
1249         }
1250         else {
1251                 gt->gt_statfs_slow = 1;
1252                 gt->gt_statfs_quantum = 30;
1253         }
1254         spin_unlock(&gt->gt_spin);
1255
1256         gfs2_online_uevent(sdp);
1257         return 0;
1258 }
1259
1260 /**
1261  * gfs2_drop_inode - Drop an inode (test for remote unlink)
1262  * @inode: The inode to drop
1263  *
1264  * If we've received a callback on an iopen lock then its because a
1265  * remote node tried to deallocate the inode but failed due to this node
1266  * still having the inode open. Here we mark the link count zero
1267  * since we know that it must have reached zero if the GLF_DEMOTE flag
1268  * is set on the iopen glock. If we didn't do a disk read since the
1269  * remote node removed the final link then we might otherwise miss
1270  * this event. This check ensures that this node will deallocate the
1271  * inode's blocks, or alternatively pass the baton on to another
1272  * node for later deallocation.
1273  */
1274
1275 static int gfs2_drop_inode(struct inode *inode)
1276 {
1277         struct gfs2_inode *ip = GFS2_I(inode);
1278
1279         if (inode->i_nlink) {
1280                 struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
1281                 if (gl && test_bit(GLF_DEMOTE, &gl->gl_flags))
1282                         clear_nlink(inode);
1283         }
1284         return generic_drop_inode(inode);
1285 }
1286
1287 static int is_ancestor(const struct dentry *d1, const struct dentry *d2)
1288 {
1289         do {
1290                 if (d1 == d2)
1291                         return 1;
1292                 d1 = d1->d_parent;
1293         } while (!IS_ROOT(d1));
1294         return 0;
1295 }
1296
1297 /**
1298  * gfs2_show_options - Show mount options for /proc/mounts
1299  * @s: seq_file structure
1300  * @root: root of this (sub)tree
1301  *
1302  * Returns: 0 on success or error code
1303  */
1304
1305 static int gfs2_show_options(struct seq_file *s, struct dentry *root)
1306 {
1307         struct gfs2_sbd *sdp = root->d_sb->s_fs_info;
1308         struct gfs2_args *args = &sdp->sd_args;
1309         int val;
1310
1311         if (is_ancestor(root, sdp->sd_master_dir))
1312                 seq_printf(s, ",meta");
1313         if (args->ar_lockproto[0])
1314                 seq_printf(s, ",lockproto=%s", args->ar_lockproto);
1315         if (args->ar_locktable[0])
1316                 seq_printf(s, ",locktable=%s", args->ar_locktable);
1317         if (args->ar_hostdata[0])
1318                 seq_printf(s, ",hostdata=%s", args->ar_hostdata);
1319         if (args->ar_spectator)
1320                 seq_printf(s, ",spectator");
1321         if (args->ar_localflocks)
1322                 seq_printf(s, ",localflocks");
1323         if (args->ar_debug)
1324                 seq_printf(s, ",debug");
1325         if (args->ar_posix_acl)
1326                 seq_printf(s, ",acl");
1327         if (args->ar_quota != GFS2_QUOTA_DEFAULT) {
1328                 char *state;
1329                 switch (args->ar_quota) {
1330                 case GFS2_QUOTA_OFF:
1331                         state = "off";
1332                         break;
1333                 case GFS2_QUOTA_ACCOUNT:
1334                         state = "account";
1335                         break;
1336                 case GFS2_QUOTA_ON:
1337                         state = "on";
1338                         break;
1339                 default:
1340                         state = "unknown";
1341                         break;
1342                 }
1343                 seq_printf(s, ",quota=%s", state);
1344         }
1345         if (args->ar_suiddir)
1346                 seq_printf(s, ",suiddir");
1347         if (args->ar_data != GFS2_DATA_DEFAULT) {
1348                 char *state;
1349                 switch (args->ar_data) {
1350                 case GFS2_DATA_WRITEBACK:
1351                         state = "writeback";
1352                         break;
1353                 case GFS2_DATA_ORDERED:
1354                         state = "ordered";
1355                         break;
1356                 default:
1357                         state = "unknown";
1358                         break;
1359                 }
1360                 seq_printf(s, ",data=%s", state);
1361         }
1362         if (args->ar_discard)
1363                 seq_printf(s, ",discard");
1364         val = sdp->sd_tune.gt_logd_secs;
1365         if (val != 30)
1366                 seq_printf(s, ",commit=%d", val);
1367         val = sdp->sd_tune.gt_statfs_quantum;
1368         if (val != 30)
1369                 seq_printf(s, ",statfs_quantum=%d", val);
1370         else if (sdp->sd_tune.gt_statfs_slow)
1371                 seq_puts(s, ",statfs_quantum=0");
1372         val = sdp->sd_tune.gt_quota_quantum;
1373         if (val != 60)
1374                 seq_printf(s, ",quota_quantum=%d", val);
1375         if (args->ar_statfs_percent)
1376                 seq_printf(s, ",statfs_percent=%d", args->ar_statfs_percent);
1377         if (args->ar_errors != GFS2_ERRORS_DEFAULT) {
1378                 const char *state;
1379
1380                 switch (args->ar_errors) {
1381                 case GFS2_ERRORS_WITHDRAW:
1382                         state = "withdraw";
1383                         break;
1384                 case GFS2_ERRORS_PANIC:
1385                         state = "panic";
1386                         break;
1387                 default:
1388                         state = "unknown";
1389                         break;
1390                 }
1391                 seq_printf(s, ",errors=%s", state);
1392         }
1393         if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags))
1394                 seq_printf(s, ",nobarrier");
1395         if (test_bit(SDF_DEMOTE, &sdp->sd_flags))
1396                 seq_printf(s, ",demote_interface_used");
1397         if (args->ar_rgrplvb)
1398                 seq_printf(s, ",rgrplvb");
1399         return 0;
1400 }
1401
1402 static void gfs2_final_release_pages(struct gfs2_inode *ip)
1403 {
1404         struct inode *inode = &ip->i_inode;
1405         struct gfs2_glock *gl = ip->i_gl;
1406
1407         truncate_inode_pages(gfs2_glock2aspace(ip->i_gl), 0);
1408         truncate_inode_pages(&inode->i_data, 0);
1409
1410         if (atomic_read(&gl->gl_revokes) == 0) {
1411                 clear_bit(GLF_LFLUSH, &gl->gl_flags);
1412                 clear_bit(GLF_DIRTY, &gl->gl_flags);
1413         }
1414 }
1415
1416 static int gfs2_dinode_dealloc(struct gfs2_inode *ip)
1417 {
1418         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1419         struct gfs2_rgrpd *rgd;
1420         struct gfs2_holder gh;
1421         int error;
1422
1423         if (gfs2_get_inode_blocks(&ip->i_inode) != 1) {
1424                 gfs2_consist_inode(ip);
1425                 return -EIO;
1426         }
1427
1428         error = gfs2_rindex_update(sdp);
1429         if (error)
1430                 return error;
1431
1432         error = gfs2_quota_hold(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
1433         if (error)
1434                 return error;
1435
1436         rgd = gfs2_blk2rgrpd(sdp, ip->i_no_addr, 1);
1437         if (!rgd) {
1438                 gfs2_consist_inode(ip);
1439                 error = -EIO;
1440                 goto out_qs;
1441         }
1442
1443         error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, &gh);
1444         if (error)
1445                 goto out_qs;
1446
1447         error = gfs2_trans_begin(sdp, RES_RG_BIT + RES_STATFS + RES_QUOTA,
1448                                  sdp->sd_jdesc->jd_blocks);
1449         if (error)
1450                 goto out_rg_gunlock;
1451
1452         gfs2_free_di(rgd, ip);
1453
1454         gfs2_final_release_pages(ip);
1455
1456         gfs2_trans_end(sdp);
1457
1458 out_rg_gunlock:
1459         gfs2_glock_dq_uninit(&gh);
1460 out_qs:
1461         gfs2_quota_unhold(ip);
1462         return error;
1463 }
1464
1465 /**
1466  * gfs2_evict_inode - Remove an inode from cache
1467  * @inode: The inode to evict
1468  *
1469  * There are three cases to consider:
1470  * 1. i_nlink == 0, we are final opener (and must deallocate)
1471  * 2. i_nlink == 0, we are not the final opener (and cannot deallocate)
1472  * 3. i_nlink > 0
1473  *
1474  * If the fs is read only, then we have to treat all cases as per #3
1475  * since we are unable to do any deallocation. The inode will be
1476  * deallocated by the next read/write node to attempt an allocation
1477  * in the same resource group
1478  *
1479  * We have to (at the moment) hold the inodes main lock to cover
1480  * the gap between unlocking the shared lock on the iopen lock and
1481  * taking the exclusive lock. I'd rather do a shared -> exclusive
1482  * conversion on the iopen lock, but we can change that later. This
1483  * is safe, just less efficient.
1484  */
1485
1486 static void gfs2_evict_inode(struct inode *inode)
1487 {
1488         struct super_block *sb = inode->i_sb;
1489         struct gfs2_sbd *sdp = sb->s_fs_info;
1490         struct gfs2_inode *ip = GFS2_I(inode);
1491         struct gfs2_holder gh;
1492         int error;
1493
1494         if (inode->i_nlink || (sb->s_flags & MS_RDONLY))
1495                 goto out;
1496
1497         /* Must not read inode block until block type has been verified */
1498         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_SKIP, &gh);
1499         if (unlikely(error)) {
1500                 gfs2_glock_dq_uninit(&ip->i_iopen_gh);
1501                 goto out;
1502         }
1503
1504         if (!test_bit(GIF_ALLOC_FAILED, &ip->i_flags)) {
1505                 error = gfs2_check_blk_type(sdp, ip->i_no_addr, GFS2_BLKST_UNLINKED);
1506                 if (error)
1507                         goto out_truncate;
1508         }
1509
1510         if (test_bit(GIF_INVALID, &ip->i_flags)) {
1511                 error = gfs2_inode_refresh(ip);
1512                 if (error)
1513                         goto out_truncate;
1514         }
1515
1516         ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
1517         gfs2_glock_dq_wait(&ip->i_iopen_gh);
1518         gfs2_holder_reinit(LM_ST_EXCLUSIVE, LM_FLAG_TRY_1CB | GL_NOCACHE, &ip->i_iopen_gh);
1519         error = gfs2_glock_nq(&ip->i_iopen_gh);
1520         if (error)
1521                 goto out_truncate;
1522
1523         /* Case 1 starts here */
1524
1525         if (S_ISDIR(inode->i_mode) &&
1526             (ip->i_diskflags & GFS2_DIF_EXHASH)) {
1527                 error = gfs2_dir_exhash_dealloc(ip);
1528                 if (error)
1529                         goto out_unlock;
1530         }
1531
1532         if (ip->i_eattr) {
1533                 error = gfs2_ea_dealloc(ip);
1534                 if (error)
1535                         goto out_unlock;
1536         }
1537
1538         if (!gfs2_is_stuffed(ip)) {
1539                 error = gfs2_file_dealloc(ip);
1540                 if (error)
1541                         goto out_unlock;
1542         }
1543
1544         error = gfs2_dinode_dealloc(ip);
1545         goto out_unlock;
1546
1547 out_truncate:
1548         gfs2_log_flush(sdp, ip->i_gl);
1549         if (test_bit(GLF_DIRTY, &ip->i_gl->gl_flags)) {
1550                 struct address_space *metamapping = gfs2_glock2aspace(ip->i_gl);
1551                 filemap_fdatawrite(metamapping);
1552                 filemap_fdatawait(metamapping);
1553         }
1554         write_inode_now(inode, 1);
1555         gfs2_ail_flush(ip->i_gl, 0);
1556
1557         /* Case 2 starts here */
1558         error = gfs2_trans_begin(sdp, 0, sdp->sd_jdesc->jd_blocks);
1559         if (error)
1560                 goto out_unlock;
1561         /* Needs to be done before glock release & also in a transaction */
1562         truncate_inode_pages(&inode->i_data, 0);
1563         gfs2_trans_end(sdp);
1564
1565 out_unlock:
1566         /* Error path for case 1 */
1567         if (gfs2_rs_active(ip->i_res))
1568                 gfs2_rs_deltree(ip, ip->i_res);
1569
1570         if (test_bit(HIF_HOLDER, &ip->i_iopen_gh.gh_iflags))
1571                 gfs2_glock_dq(&ip->i_iopen_gh);
1572         gfs2_holder_uninit(&ip->i_iopen_gh);
1573         gfs2_glock_dq_uninit(&gh);
1574         if (error && error != GLR_TRYFAILED && error != -EROFS)
1575                 fs_warn(sdp, "gfs2_evict_inode: %d\n", error);
1576 out:
1577         /* Case 3 starts here */
1578         truncate_inode_pages(&inode->i_data, 0);
1579         gfs2_rs_delete(ip);
1580         clear_inode(inode);
1581         gfs2_dir_hash_inval(ip);
1582         ip->i_gl->gl_object = NULL;
1583         flush_delayed_work(&ip->i_gl->gl_work);
1584         gfs2_glock_add_to_lru(ip->i_gl);
1585         gfs2_glock_put(ip->i_gl);
1586         ip->i_gl = NULL;
1587         if (ip->i_iopen_gh.gh_gl) {
1588                 ip->i_iopen_gh.gh_gl->gl_object = NULL;
1589                 gfs2_glock_dq_uninit(&ip->i_iopen_gh);
1590         }
1591 }
1592
1593 static struct inode *gfs2_alloc_inode(struct super_block *sb)
1594 {
1595         struct gfs2_inode *ip;
1596
1597         ip = kmem_cache_alloc(gfs2_inode_cachep, GFP_KERNEL);
1598         if (ip) {
1599                 ip->i_flags = 0;
1600                 ip->i_gl = NULL;
1601                 ip->i_rgd = NULL;
1602                 ip->i_res = NULL;
1603         }
1604         return &ip->i_inode;
1605 }
1606
1607 static void gfs2_i_callback(struct rcu_head *head)
1608 {
1609         struct inode *inode = container_of(head, struct inode, i_rcu);
1610         kmem_cache_free(gfs2_inode_cachep, inode);
1611 }
1612
1613 static void gfs2_destroy_inode(struct inode *inode)
1614 {
1615         call_rcu(&inode->i_rcu, gfs2_i_callback);
1616 }
1617
1618 const struct super_operations gfs2_super_ops = {
1619         .alloc_inode            = gfs2_alloc_inode,
1620         .destroy_inode          = gfs2_destroy_inode,
1621         .write_inode            = gfs2_write_inode,
1622         .dirty_inode            = gfs2_dirty_inode,
1623         .evict_inode            = gfs2_evict_inode,
1624         .put_super              = gfs2_put_super,
1625         .sync_fs                = gfs2_sync_fs,
1626         .freeze_fs              = gfs2_freeze,
1627         .unfreeze_fs            = gfs2_unfreeze,
1628         .statfs                 = gfs2_statfs,
1629         .remount_fs             = gfs2_remount_fs,
1630         .drop_inode             = gfs2_drop_inode,
1631         .show_options           = gfs2_show_options,
1632 };
1633