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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  11
  12 #include <linux/bio.h>
  13 #include <linux/sched.h>
  14 #include <linux/slab.h>
  15 #include <linux/spinlock.h>
  16 #include <linux/completion.h>
  17 #include <linux/buffer_head.h>
  18 #include <linux/statfs.h>
  19 #include <linux/seq_file.h>
  20 #include <linux/mount.h>
  21 #include <linux/kthread.h>
  22 #include <linux/delay.h>
  23 #include <linux/gfs2_ondisk.h>
  24 #include <linux/crc32.h>
  25 #include <linux/time.h>
  26 #include <linux/wait.h>
  27 #include <linux/writeback.h>
  28 #include <linux/backing-dev.h>
  29
  30 #include "gfs2.h"
  31 #include "incore.h"
  32 #include "bmap.h"
  33 #include "dir.h"
  34 #include "glock.h"
  35 #include "glops.h"
  36 #include "inode.h"
  37 #include "log.h"
  38 #include "meta_io.h"
  39 #include "quota.h"
  40 #include "recovery.h"
  41 #include "rgrp.h"
  42 #include "super.h"
  43 #include "trans.h"
  44 #include "util.h"
  45 #include "sys.h"
  46 #include "xattr.h"
  47
  48 #define args_neq(a1, a2, x) ((a1)->ar_##x != (a2)->ar_##x)
  49
  50 enum {
  51         Opt_lockproto,
  52         Opt_locktable,
  53         Opt_hostdata,
  54         Opt_spectator,
  55         Opt_ignore_local_fs,
  56         Opt_localflocks,
  57         Opt_localcaching,
  58         Opt_debug,
  59         Opt_nodebug,
  60         Opt_upgrade,
  61         Opt_acl,
  62         Opt_noacl,
  63         Opt_quota_off,
  64         Opt_quota_account,
  65         Opt_quota_on,
  66         Opt_quota,
  67         Opt_noquota,
  68         Opt_suiddir,
  69         Opt_nosuiddir,
  70         Opt_data_writeback,
  71         Opt_data_ordered,
  72         Opt_meta,
  73         Opt_discard,
  74         Opt_nodiscard,
  75         Opt_commit,
  76         Opt_err_withdraw,
  77         Opt_err_panic,
  78         Opt_statfs_quantum,
  79         Opt_statfs_percent,
  80         Opt_quota_quantum,
  81         Opt_barrier,
  82         Opt_nobarrier,
  83         Opt_rgrplvb,
  84         Opt_norgrplvb,
  85         Opt_error,
  86 };
  87
  88 static const match_table_t tokens = {
  89         {Opt_lockproto, "lockproto=%s"},
  90         {Opt_locktable, "locktable=%s"},
  91         {Opt_hostdata, "hostdata=%s"},
  92         {Opt_spectator, "spectator"},
  93         {Opt_spectator, "norecovery"},
  94         {Opt_ignore_local_fs, "ignore_local_fs"},
  95         {Opt_localflocks, "localflocks"},
  96         {Opt_localcaching, "localcaching"},
  97         {Opt_debug, "debug"},
  98         {Opt_nodebug, "nodebug"},
  99         {Opt_upgrade, "upgrade"},
 100         {Opt_acl, "acl"},
 101         {Opt_noacl, "noacl"},
 102         {Opt_quota_off, "quota=off"},
 103         {Opt_quota_account, "quota=account"},
 104         {Opt_quota_on, "quota=on"},
 105         {Opt_quota, "quota"},
 106         {Opt_noquota, "noquota"},
 107         {Opt_suiddir, "suiddir"},
 108         {Opt_nosuiddir, "nosuiddir"},
 109         {Opt_data_writeback, "data=writeback"},
 110         {Opt_data_ordered, "data=ordered"},
 111         {Opt_meta, "meta"},
 112         {Opt_discard, "discard"},
 113         {Opt_nodiscard, "nodiscard"},
 114         {Opt_commit, "commit=%d"},
 115         {Opt_err_withdraw, "errors=withdraw"},
 116         {Opt_err_panic, "errors=panic"},
 117         {Opt_statfs_quantum, "statfs_quantum=%d"},
 118         {Opt_statfs_percent, "statfs_percent=%d"},
 119         {Opt_quota_quantum, "quota_quantum=%d"},
 120         {Opt_barrier, "barrier"},
 121         {Opt_nobarrier, "nobarrier"},
 122         {Opt_rgrplvb, "rgrplvb"},
 123         {Opt_norgrplvb, "norgrplvb"},
 124         {Opt_error, NULL}
 125 };
 126
 127 /**
 128  * gfs2_mount_args - Parse mount options
 129  * @args: The structure into which the parsed options will be written
 130  * @options: The options to parse
 131  *
 132  * Return: errno
 133  */
 134
 135 int gfs2_mount_args(struct gfs2_args *args, char *options)
 136 {
 137         char *o;
 138         int token;
 139         substring_t tmp[MAX_OPT_ARGS];
 140         int rv;
 141
 142         /* Split the options into tokens with the "," character and
 143            process them */
 144
 145         while (1) {
 146                 o = strsep(&options, ",");
 147                 if (o == NULL)
 148                         break;
 149                 if (*o == '\0')
 150                         continue;
 151
 152                 token = match_token(o, tokens, tmp);
 153                 switch (token) {
 154                 case Opt_lockproto:
 155                         match_strlcpy(args->ar_lockproto, &tmp[0],
 156                                       GFS2_LOCKNAME_LEN);
 157                         break;
 158                 case Opt_locktable:
 159                         match_strlcpy(args->ar_locktable, &tmp[0],
 160                                       GFS2_LOCKNAME_LEN);
 161                         break;
 162                 case Opt_hostdata:
 163                         match_strlcpy(args->ar_hostdata, &tmp[0],
 164                                       GFS2_LOCKNAME_LEN);
 165                         break;
 166                 case Opt_spectator:
 167                         args->ar_spectator = 1;
 168                         break;
 169                 case Opt_ignore_local_fs:
 170                         /* Retained for backwards compat only */
 171                         break;
 172                 case Opt_localflocks:
 173                         args->ar_localflocks = 1;
 174                         break;
 175                 case Opt_localcaching:
 176                         /* Retained for backwards compat only */
 177                         break;
 178                 case Opt_debug:
 179                         if (args->ar_errors == GFS2_ERRORS_PANIC) {
 180                                 pr_warn("-o debug and -o errors=panic are mutually exclusive\n");
 181                                 return -EINVAL;
 182                         }
 183                         args->ar_debug = 1;
 184                         break;
 185                 case Opt_nodebug:
 186                         args->ar_debug = 0;
 187                         break;
 188                 case Opt_upgrade:
 189                         /* Retained for backwards compat only */
 190                         break;
 191                 case Opt_acl:
 192                         args->ar_posix_acl = 1;
 193                         break;
 194                 case Opt_noacl:
 195                         args->ar_posix_acl = 0;
 196                         break;
 197                 case Opt_quota_off:
 198                 case Opt_noquota:
 199                         args->ar_quota = GFS2_QUOTA_OFF;
 200                         break;
 201                 case Opt_quota_account:
 202                         args->ar_quota = GFS2_QUOTA_ACCOUNT;
 203                         break;
 204                 case Opt_quota_on:
 205                 case Opt_quota:
 206                         args->ar_quota = GFS2_QUOTA_ON;
 207                         break;
 208                 case Opt_suiddir:
 209                         args->ar_suiddir = 1;
 210                         break;
 211                 case Opt_nosuiddir:
 212                         args->ar_suiddir = 0;
 213                         break;
 214                 case Opt_data_writeback:
 215                         args->ar_data = GFS2_DATA_WRITEBACK;
 216                         break;
 217                 case Opt_data_ordered:
 218                         args->ar_data = GFS2_DATA_ORDERED;
 219                         break;
 220                 case Opt_meta:
 221                         args->ar_meta = 1;
 222                         break;
 223                 case Opt_discard:
 224                         args->ar_discard = 1;
 225                         break;
 226                 case Opt_nodiscard:
 227                         args->ar_discard = 0;
 228                         break;
 229                 case Opt_commit:
 230                         rv = match_int(&tmp[0], &args->ar_commit);
 231                         if (rv || args->ar_commit <= 0) {
 232                                 pr_warn("commit mount option requires a positive numeric argument\n");
 233                                 return rv ? rv : -EINVAL;
 234                         }
 235                         break;
 236                 case Opt_statfs_quantum:
 237                         rv = match_int(&tmp[0], &args->ar_statfs_quantum);
 238                         if (rv || args->ar_statfs_quantum < 0) {
 239                                 pr_warn("statfs_quantum mount option requires a non-negative numeric argument\n");
 240                                 return rv ? rv : -EINVAL;
 241                         }
 242                         break;
 243                 case Opt_quota_quantum:
 244                         rv = match_int(&tmp[0], &args->ar_quota_quantum);
 245                         if (rv || args->ar_quota_quantum <= 0) {
 246                                 pr_warn("quota_quantum mount option requires a positive numeric argument\n");
 247                                 return rv ? rv : -EINVAL;
 248                         }
 249                         break;
 250                 case Opt_statfs_percent:
 251                         rv = match_int(&tmp[0], &args->ar_statfs_percent);
 252                         if (rv || args->ar_statfs_percent < 0 ||
 253                             args->ar_statfs_percent > 100) {
 254                                 pr_warn("statfs_percent mount option requires a numeric argument between 0 and 100\n");
 255                                 return rv ? rv : -EINVAL;
 256                         }
 257                         break;
 258                 case Opt_err_withdraw:
 259                         args->ar_errors = GFS2_ERRORS_WITHDRAW;
 260                         break;
 261                 case Opt_err_panic:
 262                         if (args->ar_debug) {
 263                                 pr_warn("-o debug and -o errors=panic 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                         pr_warn("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;
 299         struct gfs2_jdesc *jd;
 300
 301         spin_lock(&sdp->sd_jindex_spin);
 302         list_add(&list, &sdp->sd_jindex_list);
 303         list_del_init(&sdp->sd_jindex_list);
 304         sdp->sd_journals = 0;
 305         spin_unlock(&sdp->sd_jindex_spin);
 306
 307         while (!list_empty(&list)) {
 308                 jd = list_entry(list.next, struct gfs2_jdesc, jd_list);
 309                 gfs2_free_journal_extents(jd);
 310                 list_del(&jd->jd_list);
 311                 iput(jd->jd_inode);
 312                 kfree(jd);
 313         }
 314 }
 315
 316 static struct gfs2_jdesc *jdesc_find_i(struct list_head *head, unsigned int jid)
 317 {
 318         struct gfs2_jdesc *jd;
 319         int found = 0;
 320
 321         list_for_each_entry(jd, head, jd_list) {
 322                 if (jd->jd_jid == jid) {
 323                         found = 1;
 324                         break;
 325                 }
 326         }
 327
 328         if (!found)
 329                 jd = NULL;
 330
 331         return jd;
 332 }
 333
 334 struct gfs2_jdesc *gfs2_jdesc_find(struct gfs2_sbd *sdp, unsigned int jid)
 335 {
 336         struct gfs2_jdesc *jd;
 337
 338         spin_lock(&sdp->sd_jindex_spin);
 339         jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
 340         spin_unlock(&sdp->sd_jindex_spin);
 341
 342         return jd;
 343 }
 344
 345 int gfs2_jdesc_check(struct gfs2_jdesc *jd)
 346 {
 347         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
 348         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 349         u64 size = i_size_read(jd->jd_inode);
 350
 351         if (gfs2_check_internal_file_size(jd->jd_inode, 8 << 20, 1 << 30))
 352                 return -EIO;
 353
 354         jd->jd_blocks = size >> sdp->sd_sb.sb_bsize_shift;
 355
 356         if (gfs2_write_alloc_required(ip, 0, size)) {
 357                 gfs2_consist_inode(ip);
 358                 return -EIO;
 359         }
 360
 361         return 0;
 362 }
 363
 364 static int init_threads(struct gfs2_sbd *sdp)
 365 {
 366         struct task_struct *p;
 367         int error = 0;
 368
 369         p = kthread_run(gfs2_logd, sdp, "gfs2_logd");
 370         if (IS_ERR(p)) {
 371                 error = PTR_ERR(p);
 372                 fs_err(sdp, "can't start logd thread: %d\n", error);
 373                 return error;
 374         }
 375         sdp->sd_logd_process = p;
 376
 377         p = kthread_run(gfs2_quotad, sdp, "gfs2_quotad");
 378         if (IS_ERR(p)) {
 379                 error = PTR_ERR(p);
 380                 fs_err(sdp, "can't start quotad thread: %d\n", error);
 381                 goto fail;
 382         }
 383         sdp->sd_quotad_process = p;
 384         return 0;
 385
 386 fail:
 387         kthread_stop(sdp->sd_logd_process);
 388         return error;
 389 }
 390
 391 /**
 392  * gfs2_make_fs_rw - Turn a Read-Only FS into a Read-Write one
 393  * @sdp: the filesystem
 394  *
 395  * Returns: errno
 396  */
 397
 398 int gfs2_make_fs_rw(struct gfs2_sbd *sdp)
 399 {
 400         struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
 401         struct gfs2_glock *j_gl = ip->i_gl;
 402         struct gfs2_holder thaw_gh;
 403         struct gfs2_log_header_host head;
 404         int error;
 405
 406         error = init_threads(sdp);
 407         if (error)
 408                 return error;
 409
 410         error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED, 0,
 411                                    &thaw_gh);
 412         if (error)
 413                 goto fail_threads;
 414
 415         j_gl->gl_ops->go_inval(j_gl, DIO_METADATA);
 416
 417         error = gfs2_find_jhead(sdp->sd_jdesc, &head);
 418         if (error)
 419                 goto fail;
 420
 421         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 422                 gfs2_consist(sdp);
 423                 error = -EIO;
 424                 goto fail;
 425         }
 426
 427         /*  Initialize some head of the log stuff  */
 428         sdp->sd_log_sequence = head.lh_sequence + 1;
 429         gfs2_log_pointers_init(sdp, head.lh_blkno);
 430
 431         error = gfs2_quota_init(sdp);
 432         if (error)
 433                 goto fail;
 434
 435         set_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 436
 437         gfs2_glock_dq_uninit(&thaw_gh);
 438
 439         return 0;
 440
 441 fail:
 442         thaw_gh.gh_flags |= GL_NOCACHE;
 443         gfs2_glock_dq_uninit(&thaw_gh);
 444 fail_threads:
 445         kthread_stop(sdp->sd_quotad_process);
 446         kthread_stop(sdp->sd_logd_process);
 447         return error;
 448 }
 449
 450 void gfs2_statfs_change_in(struct gfs2_statfs_change_host *sc, const void *buf)
 451 {
 452         const struct gfs2_statfs_change *str = buf;
 453
 454         sc->sc_total = be64_to_cpu(str->sc_total);
 455         sc->sc_free = be64_to_cpu(str->sc_free);
 456         sc->sc_dinodes = be64_to_cpu(str->sc_dinodes);
 457 }
 458
 459 static void gfs2_statfs_change_out(const struct gfs2_statfs_change_host *sc, void *buf)
 460 {
 461         struct gfs2_statfs_change *str = buf;
 462
 463         str->sc_total = cpu_to_be64(sc->sc_total);
 464         str->sc_free = cpu_to_be64(sc->sc_free);
 465         str->sc_dinodes = cpu_to_be64(sc->sc_dinodes);
 466 }
 467
 468 int gfs2_statfs_init(struct gfs2_sbd *sdp)
 469 {
 470         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 471         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 472         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 473         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 474         struct buffer_head *m_bh, *l_bh;
 475         struct gfs2_holder gh;
 476         int error;
 477
 478         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 479                                    &gh);
 480         if (error)
 481                 return error;
 482
 483         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 484         if (error)
 485                 goto out;
 486
 487         if (sdp->sd_args.ar_spectator) {
 488                 spin_lock(&sdp->sd_statfs_spin);
 489                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 490                                       sizeof(struct gfs2_dinode));
 491                 spin_unlock(&sdp->sd_statfs_spin);
 492         } else {
 493                 error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 494                 if (error)
 495                         goto out_m_bh;
 496
 497                 spin_lock(&sdp->sd_statfs_spin);
 498                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 499                                       sizeof(struct gfs2_dinode));
 500                 gfs2_statfs_change_in(l_sc, l_bh->b_data +
 501                                       sizeof(struct gfs2_dinode));
 502                 spin_unlock(&sdp->sd_statfs_spin);
 503
 504                 brelse(l_bh);
 505         }
 506
 507 out_m_bh:
 508         brelse(m_bh);
 509 out:
 510         gfs2_glock_dq_uninit(&gh);
 511         return 0;
 512 }
 513
 514 void gfs2_statfs_change(struct gfs2_sbd *sdp, s64 total, s64 free,
 515                         s64 dinodes)
 516 {
 517         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 518         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 519         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 520         struct buffer_head *l_bh;
 521         s64 x, y;
 522         int need_sync = 0;
 523         int error;
 524
 525         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 526         if (error)
 527                 return;
 528
 529         gfs2_trans_add_meta(l_ip->i_gl, l_bh);
 530
 531         spin_lock(&sdp->sd_statfs_spin);
 532         l_sc->sc_total += total;
 533         l_sc->sc_free += free;
 534         l_sc->sc_dinodes += dinodes;
 535         gfs2_statfs_change_out(l_sc, l_bh->b_data + sizeof(struct gfs2_dinode));
 536         if (sdp->sd_args.ar_statfs_percent) {
 537                 x = 100 * l_sc->sc_free;
 538                 y = m_sc->sc_free * sdp->sd_args.ar_statfs_percent;
 539                 if (x >= y || x <= -y)
 540                         need_sync = 1;
 541         }
 542         spin_unlock(&sdp->sd_statfs_spin);
 543
 544         brelse(l_bh);
 545         if (need_sync)
 546                 gfs2_wake_up_statfs(sdp);
 547 }
 548
 549 void update_statfs(struct gfs2_sbd *sdp, struct buffer_head *m_bh,
 550                    struct buffer_head *l_bh)
 551 {
 552         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 553         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 554         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 555         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 556
 557         gfs2_trans_add_meta(l_ip->i_gl, l_bh);
 558
 559         spin_lock(&sdp->sd_statfs_spin);
 560         m_sc->sc_total += l_sc->sc_total;
 561         m_sc->sc_free += l_sc->sc_free;
 562         m_sc->sc_dinodes += l_sc->sc_dinodes;
 563         memset(l_sc, 0, sizeof(struct gfs2_statfs_change));
 564         memset(l_bh->b_data + sizeof(struct gfs2_dinode),
 565                0, sizeof(struct gfs2_statfs_change));
 566         spin_unlock(&sdp->sd_statfs_spin);
 567
 568         gfs2_trans_add_meta(m_ip->i_gl, m_bh);
 569         gfs2_statfs_change_out(m_sc, m_bh->b_data + sizeof(struct gfs2_dinode));
 570 }
 571
 572 int gfs2_statfs_sync(struct super_block *sb, int type)
 573 {
 574         struct gfs2_sbd *sdp = sb->s_fs_info;
 575         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 576         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 577         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 578         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 579         struct gfs2_holder gh;
 580         struct buffer_head *m_bh, *l_bh;
 581         int error;
 582
 583         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 584                                    &gh);
 585         if (error)
 586                 return error;
 587
 588         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 589         if (error)
 590                 goto out;
 591
 592         spin_lock(&sdp->sd_statfs_spin);
 593         gfs2_statfs_change_in(m_sc, m_bh->b_data +
 594                               sizeof(struct gfs2_dinode));
 595         if (!l_sc->sc_total && !l_sc->sc_free && !l_sc->sc_dinodes) {
 596                 spin_unlock(&sdp->sd_statfs_spin);
 597                 goto out_bh;
 598         }
 599         spin_unlock(&sdp->sd_statfs_spin);
 600
 601         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 602         if (error)
 603                 goto out_bh;
 604
 605         error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
 606         if (error)
 607                 goto out_bh2;
 608
 609         update_statfs(sdp, m_bh, l_bh);
 610         sdp->sd_statfs_force_sync = 0;
 611
 612         gfs2_trans_end(sdp);
 613
 614 out_bh2:
 615         brelse(l_bh);
 616 out_bh:
 617         brelse(m_bh);
 618 out:
 619         gfs2_glock_dq_uninit(&gh);
 620         return error;
 621 }
 622
 623 struct lfcc {
 624         struct list_head list;
 625         struct gfs2_holder gh;
 626 };
 627
 628 /**
 629  * gfs2_lock_fs_check_clean - Stop all writes to the FS and check that all
 630  *                            journals are clean
 631  * @sdp: the file system
 632  * @state: the state to put the transaction lock into
 633  * @t_gh: the hold on the transaction lock
 634  *
 635  * Returns: errno
 636  */
 637
 638 static int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp,
 639                                     struct gfs2_holder *freeze_gh)
 640 {
 641         struct gfs2_inode *ip;
 642         struct gfs2_jdesc *jd;
 643         struct lfcc *lfcc;
 644         LIST_HEAD(list);
 645         struct gfs2_log_header_host lh;
 646         struct gfs2_inode *dip = GFS2_I(sdp->sd_root_dir->d_inode);
 647         int error;
 648
 649         error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0,
 650                                    &sdp->sd_freeze_root_gh);
 651         if (error)
 652                 return error;
 653         atomic_set(&sdp->sd_frozen_root, 1);
 654         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 655                 lfcc = kmalloc(sizeof(struct lfcc), GFP_KERNEL);
 656                 if (!lfcc) {
 657                         error = -ENOMEM;
 658                         goto out;
 659                 }
 660                 ip = GFS2_I(jd->jd_inode);
 661                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &lfcc->gh);
 662                 if (error) {
 663                         kfree(lfcc);
 664                         goto out;
 665                 }
 666                 list_add(&lfcc->list, &list);
 667         }
 668
 669         error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_EXCLUSIVE,
 670                                    GL_NOCACHE, freeze_gh);
 671
 672         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 673                 error = gfs2_jdesc_check(jd);
 674                 if (error)
 675                         break;
 676                 error = gfs2_find_jhead(jd, &lh);
 677                 if (error)
 678                         break;
 679                 if (!(lh.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 680                         error = -EBUSY;
 681                         break;
 682                 }
 683         }
 684
 685         if (error)
 686                 gfs2_glock_dq_uninit(freeze_gh);
 687
 688 out:
 689         while (!list_empty(&list)) {
 690                 lfcc = list_entry(list.next, struct lfcc, list);
 691                 list_del(&lfcc->list);
 692                 gfs2_glock_dq_uninit(&lfcc->gh);
 693                 kfree(lfcc);
 694         }
 695         if (error) {
 696                 atomic_dec(&sdp->sd_frozen_root);
 697                 wait_event(sdp->sd_frozen_root_wait, atomic_read(&sdp->sd_frozen_root) == 0);
 698                 gfs2_glock_dq_uninit(&sdp->sd_freeze_root_gh);
 699         }
 700         return error;
 701 }
 702
 703 void gfs2_dinode_out(const struct gfs2_inode *ip, void *buf)
 704 {
 705         struct gfs2_dinode *str = buf;
 706
 707         str->di_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
 708         str->di_header.mh_type = cpu_to_be32(GFS2_METATYPE_DI);
 709         str->di_header.mh_format = cpu_to_be32(GFS2_FORMAT_DI);
 710         str->di_num.no_addr = cpu_to_be64(ip->i_no_addr);
 711         str->di_num.no_formal_ino = cpu_to_be64(ip->i_no_formal_ino);
 712         str->di_mode = cpu_to_be32(ip->i_inode.i_mode);
 713         str->di_uid = cpu_to_be32(i_uid_read(&ip->i_inode));
 714         str->di_gid = cpu_to_be32(i_gid_read(&ip->i_inode));
 715         str->di_nlink = cpu_to_be32(ip->i_inode.i_nlink);
 716         str->di_size = cpu_to_be64(i_size_read(&ip->i_inode));
 717         str->di_blocks = cpu_to_be64(gfs2_get_inode_blocks(&ip->i_inode));
 718         str->di_atime = cpu_to_be64(ip->i_inode.i_atime.tv_sec);
 719         str->di_mtime = cpu_to_be64(ip->i_inode.i_mtime.tv_sec);
 720         str->di_ctime = cpu_to_be64(ip->i_inode.i_ctime.tv_sec);
 721
 722         str->di_goal_meta = cpu_to_be64(ip->i_goal);
 723         str->di_goal_data = cpu_to_be64(ip->i_goal);
 724         str->di_generation = cpu_to_be64(ip->i_generation);
 725
 726         str->di_flags = cpu_to_be32(ip->i_diskflags);
 727         str->di_height = cpu_to_be16(ip->i_height);
 728         str->di_payload_format = cpu_to_be32(S_ISDIR(ip->i_inode.i_mode) &&
 729                                              !(ip->i_diskflags & GFS2_DIF_EXHASH) ?
 730                                              GFS2_FORMAT_DE : 0);
 731         str->di_depth = cpu_to_be16(ip->i_depth);
 732         str->di_entries = cpu_to_be32(ip->i_entries);
 733
 734         str->di_eattr = cpu_to_be64(ip->i_eattr);
 735         str->di_atime_nsec = cpu_to_be32(ip->i_inode.i_atime.tv_nsec);
 736         str->di_mtime_nsec = cpu_to_be32(ip->i_inode.i_mtime.tv_nsec);
 737         str->di_ctime_nsec = cpu_to_be32(ip->i_inode.i_ctime.tv_nsec);
 738 }
 739
 740 /**
 741  * gfs2_write_inode - Make sure the inode is stable on the disk
 742  * @inode: The inode
 743  * @wbc: The writeback control structure
 744  *
 745  * Returns: errno
 746  */
 747
 748 static int gfs2_write_inode(struct inode *inode, struct writeback_control *wbc)
 749 {
 750         struct gfs2_inode *ip = GFS2_I(inode);
 751         struct gfs2_sbd *sdp = GFS2_SB(inode);
 752         struct address_space *metamapping = gfs2_glock2aspace(ip->i_gl);
 753         struct backing_dev_info *bdi = metamapping->backing_dev_info;
 754         int ret = 0;
 755
 756         if (wbc->sync_mode == WB_SYNC_ALL)
 757                 gfs2_log_flush(GFS2_SB(inode), ip->i_gl, NORMAL_FLUSH);
 758         if (bdi->dirty_exceeded)
 759                 gfs2_ail1_flush(sdp, wbc);
 760         else
 761                 filemap_fdatawrite(metamapping);
 762         if (wbc->sync_mode == WB_SYNC_ALL)
 763                 ret = filemap_fdatawait(metamapping);
 764         if (ret)
 765                 mark_inode_dirty_sync(inode);
 766         return ret;
 767 }
 768
 769 /**
 770  * gfs2_dirty_inode - check for atime updates
 771  * @inode: The inode in question
 772  * @flags: The type of dirty
 773  *
 774  * Unfortunately it can be called under any combination of inode
 775  * glock and transaction lock, so we have to check carefully.
 776  *
 777  * At the moment this deals only with atime - it should be possible
 778  * to expand that role in future, once a review of the locking has
 779  * been carried out.
 780  */
 781
 782 static void gfs2_dirty_inode(struct inode *inode, int flags)
 783 {
 784         struct gfs2_inode *ip = GFS2_I(inode);
 785         struct gfs2_sbd *sdp = GFS2_SB(inode);
 786         struct buffer_head *bh;
 787         struct gfs2_holder gh;
 788         int need_unlock = 0;
 789         int need_endtrans = 0;
 790         int ret;
 791
 792         if (!(flags & (I_DIRTY_DATASYNC|I_DIRTY_SYNC)))
 793                 return;
 794
 795         if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
 796                 ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
 797                 if (ret) {
 798                         fs_err(sdp, "dirty_inode: glock %d\n", ret);
 799                         return;
 800                 }
 801                 need_unlock = 1;
 802         } else if (WARN_ON_ONCE(ip->i_gl->gl_state != LM_ST_EXCLUSIVE))
 803                 return;
 804
 805         if (current->journal_info == NULL) {
 806                 ret = gfs2_trans_begin(sdp, RES_DINODE, 0);
 807                 if (ret) {
 808                         fs_err(sdp, "dirty_inode: gfs2_trans_begin %d\n", ret);
 809                         goto out;
 810                 }
 811                 need_endtrans = 1;
 812         }
 813
 814         ret = gfs2_meta_inode_buffer(ip, &bh);
 815         if (ret == 0) {
 816                 gfs2_trans_add_meta(ip->i_gl, bh);
 817                 gfs2_dinode_out(ip, bh->b_data);
 818                 brelse(bh);
 819         }
 820
 821         if (need_endtrans)
 822                 gfs2_trans_end(sdp);
 823 out:
 824         if (need_unlock)
 825                 gfs2_glock_dq_uninit(&gh);
 826 }
 827
 828 /**
 829  * gfs2_make_fs_ro - Turn a Read-Write FS into a Read-Only one
 830  * @sdp: the filesystem
 831  *
 832  * Returns: errno
 833  */
 834
 835 static int gfs2_make_fs_ro(struct gfs2_sbd *sdp)
 836 {
 837         struct gfs2_holder thaw_gh;
 838         int error;
 839
 840         error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED, GL_NOCACHE,
 841                                    &thaw_gh);
 842         if (error && !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
 843                 return error;
 844
 845         down_write(&sdp->sd_log_flush_lock);
 846         clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 847         up_write(&sdp->sd_log_flush_lock);
 848
 849         kthread_stop(sdp->sd_quotad_process);
 850         kthread_stop(sdp->sd_logd_process);
 851
 852         flush_workqueue(gfs2_delete_workqueue);
 853         gfs2_quota_sync(sdp->sd_vfs, 0);
 854         gfs2_statfs_sync(sdp->sd_vfs, 0);
 855
 856         gfs2_log_flush(sdp, NULL, SHUTDOWN_FLUSH);
 857         gfs2_assert_warn(sdp, atomic_read(&sdp->sd_log_blks_free) == sdp->sd_jdesc->jd_blocks);
 858
 859         if (thaw_gh.gh_gl)
 860                 gfs2_glock_dq_uninit(&thaw_gh);
 861
 862         gfs2_quota_cleanup(sdp);
 863
 864         return error;
 865 }
 866
 867 /**
 868  * gfs2_put_super - Unmount the filesystem
 869  * @sb: The VFS superblock
 870  *
 871  */
 872
 873 static void gfs2_put_super(struct super_block *sb)
 874 {
 875         struct gfs2_sbd *sdp = sb->s_fs_info;
 876         int error;
 877         struct gfs2_jdesc *jd;
 878
 879         /* No more recovery requests */
 880         set_bit(SDF_NORECOVERY, &sdp->sd_flags);
 881         smp_mb();
 882
 883         /* Wait on outstanding recovery */
 884 restart:
 885         spin_lock(&sdp->sd_jindex_spin);
 886         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 887                 if (!test_bit(JDF_RECOVERY, &jd->jd_flags))
 888                         continue;
 889                 spin_unlock(&sdp->sd_jindex_spin);
 890                 wait_on_bit(&jd->jd_flags, JDF_RECOVERY,
 891                             TASK_UNINTERRUPTIBLE);
 892                 goto restart;
 893         }
 894         spin_unlock(&sdp->sd_jindex_spin);
 895
 896         if (!(sb->s_flags & MS_RDONLY)) {
 897                 error = gfs2_make_fs_ro(sdp);
 898                 if (error)
 899                         gfs2_io_error(sdp);
 900         }
 901         /*  At this point, we're through modifying the disk  */
 902
 903         /*  Release stuff  */
 904
 905         iput(sdp->sd_jindex);
 906         iput(sdp->sd_statfs_inode);
 907         iput(sdp->sd_rindex);
 908         iput(sdp->sd_quota_inode);
 909
 910         gfs2_glock_put(sdp->sd_rename_gl);
 911         gfs2_glock_put(sdp->sd_freeze_gl);
 912
 913         if (!sdp->sd_args.ar_spectator) {
 914                 gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
 915                 gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
 916                 gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
 917                 gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
 918                 iput(sdp->sd_sc_inode);
 919                 iput(sdp->sd_qc_inode);
 920         }
 921
 922         gfs2_glock_dq_uninit(&sdp->sd_live_gh);
 923         gfs2_clear_rgrpd(sdp);
 924         gfs2_jindex_free(sdp);
 925         /*  Take apart glock structures and buffer lists  */
 926         gfs2_gl_hash_clear(sdp);
 927         /*  Unmount the locking protocol  */
 928         gfs2_lm_unmount(sdp);
 929
 930         /*  At this point, we're through participating in the lockspace  */
 931         gfs2_sys_fs_del(sdp);
 932 }
 933
 934 /**
 935  * gfs2_sync_fs - sync the filesystem
 936  * @sb: the superblock
 937  *
 938  * Flushes the log to disk.
 939  */
 940
 941 static int gfs2_sync_fs(struct super_block *sb, int wait)
 942 {
 943         struct gfs2_sbd *sdp = sb->s_fs_info;
 944
 945         gfs2_quota_sync(sb, -1);
 946         if (wait && sdp && !atomic_read(&sdp->sd_log_freeze))
 947                 gfs2_log_flush(sdp, NULL, NORMAL_FLUSH);
 948         return 0;
 949 }
 950
 951 /**
 952  * gfs2_freeze - prevent further writes to the filesystem
 953  * @sb: the VFS structure for the filesystem
 954  *
 955  */
 956
 957 static int gfs2_freeze(struct super_block *sb)
 958 {
 959         struct gfs2_sbd *sdp = sb->s_fs_info;
 960         int error;
 961
 962         if (test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
 963                 return -EINVAL;
 964
 965         for (;;) {
 966                 error = gfs2_lock_fs_check_clean(sdp, &sdp->sd_freeze_gh);
 967                 if (!error)
 968                         break;
 969
 970                 switch (error) {
 971                 case -EBUSY:
 972                         fs_err(sdp, "waiting for recovery before freeze\n");
 973                         break;
 974
 975                 default:
 976                         fs_err(sdp, "error freezing FS: %d\n", error);
 977                         break;
 978                 }
 979
 980                 fs_err(sdp, "retrying...\n");
 981                 msleep(1000);
 982         }
 983         return 0;
 984 }
 985
 986 /**
 987  * gfs2_unfreeze - reallow writes to the filesystem
 988  * @sb: the VFS structure for the filesystem
 989  *
 990  */
 991
 992 static int gfs2_unfreeze(struct super_block *sb)
 993 {
 994         struct gfs2_sbd *sdp = sb->s_fs_info;
 995
 996         gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
 997         atomic_dec(&sdp->sd_frozen_root);
 998         wait_event(sdp->sd_frozen_root_wait, atomic_read(&sdp->sd_frozen_root) == 0);
 999         gfs2_glock_dq_uninit(&sdp->sd_freeze_root_gh);
1000         return 0;
1001 }
1002
1003 /**
1004  * statfs_fill - fill in the sg for a given RG
1005  * @rgd: the RG
1006  * @sc: the sc structure
1007  *
1008  * Returns: 0 on success, -ESTALE if the LVB is invalid
1009  */
1010
1011 static int statfs_slow_fill(struct gfs2_rgrpd *rgd,
1012                             struct gfs2_statfs_change_host *sc)
1013 {
1014         gfs2_rgrp_verify(rgd);
1015         sc->sc_total += rgd->rd_data;
1016         sc->sc_free += rgd->rd_free;
1017         sc->sc_dinodes += rgd->rd_dinodes;
1018         return 0;
1019 }
1020
1021 /**
1022  * gfs2_statfs_slow - Stat a filesystem using asynchronous locking
1023  * @sdp: the filesystem
1024  * @sc: the sc info that will be returned
1025  *
1026  * Any error (other than a signal) will cause this routine to fall back
1027  * to the synchronous version.
1028  *
1029  * FIXME: This really shouldn't busy wait like this.
1030  *
1031  * Returns: errno
1032  */
1033
1034 static int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
1035 {
1036         struct gfs2_rgrpd *rgd_next;
1037         struct gfs2_holder *gha, *gh;
1038         unsigned int slots = 64;
1039         unsigned int x;
1040         int done;
1041         int error = 0, err;
1042
1043         memset(sc, 0, sizeof(struct gfs2_statfs_change_host));
1044         gha = kcalloc(slots, sizeof(struct gfs2_holder), GFP_KERNEL);
1045         if (!gha)
1046                 return -ENOMEM;
1047
1048         rgd_next = gfs2_rgrpd_get_first(sdp);
1049
1050         for (;;) {
1051                 done = 1;
1052
1053                 for (x = 0; x < slots; x++) {
1054                         gh = gha + x;
1055
1056                         if (gh->gh_gl && gfs2_glock_poll(gh)) {
1057                                 err = gfs2_glock_wait(gh);
1058                                 if (err) {
1059                                         gfs2_holder_uninit(gh);
1060                                         error = err;
1061                                 } else {
1062                                         if (!error)
1063                                                 error = statfs_slow_fill(
1064                                                         gh->gh_gl->gl_object, sc);
1065                                         gfs2_glock_dq_uninit(gh);
1066                                 }
1067                         }
1068
1069                         if (gh->gh_gl)
1070                                 done = 0;
1071                         else if (rgd_next && !error) {
1072                                 error = gfs2_glock_nq_init(rgd_next->rd_gl,
1073                                                            LM_ST_SHARED,
1074                                                            GL_ASYNC,
1075                                                            gh);
1076                                 rgd_next = gfs2_rgrpd_get_next(rgd_next);
1077                                 done = 0;
1078                         }
1079
1080                         if (signal_pending(current))
1081                                 error = -ERESTARTSYS;
1082                 }
1083
1084                 if (done)
1085                         break;
1086
1087                 yield();
1088         }
1089
1090         kfree(gha);
1091         return error;
1092 }
1093
1094 /**
1095  * gfs2_statfs_i - Do a statfs
1096  * @sdp: the filesystem
1097  * @sg: the sg structure
1098  *
1099  * Returns: errno
1100  */
1101
1102 static int gfs2_statfs_i(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
1103 {
1104         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
1105         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
1106
1107         spin_lock(&sdp->sd_statfs_spin);
1108
1109         *sc = *m_sc;
1110         sc->sc_total += l_sc->sc_total;
1111         sc->sc_free += l_sc->sc_free;
1112         sc->sc_dinodes += l_sc->sc_dinodes;
1113
1114         spin_unlock(&sdp->sd_statfs_spin);
1115
1116         if (sc->sc_free < 0)
1117                 sc->sc_free = 0;
1118         if (sc->sc_free > sc->sc_total)
1119                 sc->sc_free = sc->sc_total;
1120         if (sc->sc_dinodes < 0)
1121                 sc->sc_dinodes = 0;
1122
1123         return 0;
1124 }
1125
1126 /**
1127  * gfs2_statfs - Gather and return stats about the filesystem
1128  * @sb: The superblock
1129  * @statfsbuf: The buffer
1130  *
1131  * Returns: 0 on success or error code
1132  */
1133
1134 static int gfs2_statfs(struct dentry *dentry, struct kstatfs *buf)
1135 {
1136         struct super_block *sb = dentry->d_inode->i_sb;
1137         struct gfs2_sbd *sdp = sb->s_fs_info;
1138         struct gfs2_statfs_change_host sc;
1139         int error;
1140
1141         error = gfs2_rindex_update(sdp);
1142         if (error)
1143                 return error;
1144
1145         if (gfs2_tune_get(sdp, gt_statfs_slow))
1146                 error = gfs2_statfs_slow(sdp, &sc);
1147         else
1148                 error = gfs2_statfs_i(sdp, &sc);
1149
1150         if (error)
1151                 return error;
1152
1153         buf->f_type = GFS2_MAGIC;
1154         buf->f_bsize = sdp->sd_sb.sb_bsize;
1155         buf->f_blocks = sc.sc_total;
1156         buf->f_bfree = sc.sc_free;
1157         buf->f_bavail = sc.sc_free;
1158         buf->f_files = sc.sc_dinodes + sc.sc_free;
1159         buf->f_ffree = sc.sc_free;
1160         buf->f_namelen = GFS2_FNAMESIZE;
1161
1162         return 0;
1163 }
1164
1165 /**
1166  * gfs2_remount_fs - called when the FS is remounted
1167  * @sb:  the filesystem
1168  * @flags:  the remount flags
1169  * @data:  extra data passed in (not used right now)
1170  *
1171  * Returns: errno
1172  */
1173
1174 static int gfs2_remount_fs(struct super_block *sb, int *flags, char *data)
1175 {
1176         struct gfs2_sbd *sdp = sb->s_fs_info;
1177         struct gfs2_args args = sdp->sd_args; /* Default to current settings */
1178         struct gfs2_tune *gt = &sdp->sd_tune;
1179         int error;
1180
1181         sync_filesystem(sb);
1182
1183         spin_lock(&gt->gt_spin);
1184         args.ar_commit = gt->gt_logd_secs;
1185         args.ar_quota_quantum = gt->gt_quota_quantum;
1186         if (gt->gt_statfs_slow)
1187                 args.ar_statfs_quantum = 0;
1188         else
1189                 args.ar_statfs_quantum = gt->gt_statfs_quantum;
1190         spin_unlock(&gt->gt_spin);
1191         error = gfs2_mount_args(&args, data);
1192         if (error)
1193                 return error;
1194
1195         /* Not allowed to change locking details */
1196         if (strcmp(args.ar_lockproto, sdp->sd_args.ar_lockproto) ||
1197             strcmp(args.ar_locktable, sdp->sd_args.ar_locktable) ||
1198             strcmp(args.ar_hostdata, sdp->sd_args.ar_hostdata))
1199                 return -EINVAL;
1200
1201         /* Some flags must not be changed */
1202         if (args_neq(&args, &sdp->sd_args, spectator) ||
1203             args_neq(&args, &sdp->sd_args, localflocks) ||
1204             args_neq(&args, &sdp->sd_args, meta))
1205                 return -EINVAL;
1206
1207         if (sdp->sd_args.ar_spectator)
1208                 *flags |= MS_RDONLY;
1209
1210         if ((sb->s_flags ^ *flags) & MS_RDONLY) {
1211                 if (*flags & MS_RDONLY)
1212                         error = gfs2_make_fs_ro(sdp);
1213                 else
1214                         error = gfs2_make_fs_rw(sdp);
1215                 if (error)
1216                         return error;
1217         }
1218
1219         sdp->sd_args = args;
1220         if (sdp->sd_args.ar_posix_acl)
1221                 sb->s_flags |= MS_POSIXACL;
1222         else
1223                 sb->s_flags &= ~MS_POSIXACL;
1224         if (sdp->sd_args.ar_nobarrier)
1225                 set_bit(SDF_NOBARRIERS, &sdp->sd_flags);
1226         else
1227                 clear_bit(SDF_NOBARRIERS, &sdp->sd_flags);
1228         spin_lock(&gt->gt_spin);
1229         gt->gt_logd_secs = args.ar_commit;
1230         gt->gt_quota_quantum = args.ar_quota_quantum;
1231         if (args.ar_statfs_quantum) {
1232                 gt->gt_statfs_slow = 0;
1233                 gt->gt_statfs_quantum = args.ar_statfs_quantum;
1234         }
1235         else {
1236                 gt->gt_statfs_slow = 1;
1237                 gt->gt_statfs_quantum = 30;
1238         }
1239         spin_unlock(&gt->gt_spin);
1240
1241         gfs2_online_uevent(sdp);
1242         return 0;
1243 }
1244
1245 /**
1246  * gfs2_drop_inode - Drop an inode (test for remote unlink)
1247  * @inode: The inode to drop
1248  *
1249  * If we've received a callback on an iopen lock then its because a
1250  * remote node tried to deallocate the inode but failed due to this node
1251  * still having the inode open. Here we mark the link count zero
1252  * since we know that it must have reached zero if the GLF_DEMOTE flag
1253  * is set on the iopen glock. If we didn't do a disk read since the
1254  * remote node removed the final link then we might otherwise miss
1255  * this event. This check ensures that this node will deallocate the
1256  * inode's blocks, or alternatively pass the baton on to another
1257  * node for later deallocation.
1258  */
1259
1260 static int gfs2_drop_inode(struct inode *inode)
1261 {
1262         struct gfs2_inode *ip = GFS2_I(inode);
1263
1264         if (!test_bit(GIF_FREE_VFS_INODE, &ip->i_flags) && inode->i_nlink) {
1265                 struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
1266                 if (gl && test_bit(GLF_DEMOTE, &gl->gl_flags))
1267                         clear_nlink(inode);
1268         }
1269         return generic_drop_inode(inode);
1270 }
1271
1272 static int is_ancestor(const struct dentry *d1, const struct dentry *d2)
1273 {
1274         do {
1275                 if (d1 == d2)
1276                         return 1;
1277                 d1 = d1->d_parent;
1278         } while (!IS_ROOT(d1));
1279         return 0;
1280 }
1281
1282 /**
1283  * gfs2_show_options - Show mount options for /proc/mounts
1284  * @s: seq_file structure
1285  * @root: root of this (sub)tree
1286  *
1287  * Returns: 0 on success or error code
1288  */
1289
1290 static int gfs2_show_options(struct seq_file *s, struct dentry *root)
1291 {
1292         struct gfs2_sbd *sdp = root->d_sb->s_fs_info;
1293         struct gfs2_args *args = &sdp->sd_args;
1294         int val;
1295
1296         if (is_ancestor(root, sdp->sd_master_dir))
1297                 seq_puts(s, ",meta");
1298         if (args->ar_lockproto[0])
1299                 seq_printf(s, ",lockproto=%s", args->ar_lockproto);
1300         if (args->ar_locktable[0])
1301                 seq_printf(s, ",locktable=%s", args->ar_locktable);
1302         if (args->ar_hostdata[0])
1303                 seq_printf(s, ",hostdata=%s", args->ar_hostdata);
1304         if (args->ar_spectator)
1305                 seq_puts(s, ",spectator");
1306         if (args->ar_localflocks)
1307                 seq_puts(s, ",localflocks");
1308         if (args->ar_debug)
1309                 seq_puts(s, ",debug");
1310         if (args->ar_posix_acl)
1311                 seq_puts(s, ",acl");
1312         if (args->ar_quota != GFS2_QUOTA_DEFAULT) {
1313                 char *state;
1314                 switch (args->ar_quota) {
1315                 case GFS2_QUOTA_OFF:
1316                         state = "off";
1317                         break;
1318                 case GFS2_QUOTA_ACCOUNT:
1319                         state = "account";
1320                         break;
1321                 case GFS2_QUOTA_ON:
1322                         state = "on";
1323                         break;
1324                 default:
1325                         state = "unknown";
1326                         break;
1327                 }
1328                 seq_printf(s, ",quota=%s", state);
1329         }
1330         if (args->ar_suiddir)
1331                 seq_puts(s, ",suiddir");
1332         if (args->ar_data != GFS2_DATA_DEFAULT) {
1333                 char *state;
1334                 switch (args->ar_data) {
1335                 case GFS2_DATA_WRITEBACK:
1336                         state = "writeback";
1337                         break;
1338                 case GFS2_DATA_ORDERED:
1339                         state = "ordered";
1340                         break;
1341                 default:
1342                         state = "unknown";
1343                         break;
1344                 }
1345                 seq_printf(s, ",data=%s", state);
1346         }
1347         if (args->ar_discard)
1348                 seq_puts(s, ",discard");
1349         val = sdp->sd_tune.gt_logd_secs;
1350         if (val != 30)
1351                 seq_printf(s, ",commit=%d", val);
1352         val = sdp->sd_tune.gt_statfs_quantum;
1353         if (val != 30)
1354                 seq_printf(s, ",statfs_quantum=%d", val);
1355         else if (sdp->sd_tune.gt_statfs_slow)
1356                 seq_puts(s, ",statfs_quantum=0");
1357         val = sdp->sd_tune.gt_quota_quantum;
1358         if (val != 60)
1359                 seq_printf(s, ",quota_quantum=%d", val);
1360         if (args->ar_statfs_percent)
1361                 seq_printf(s, ",statfs_percent=%d", args->ar_statfs_percent);
1362         if (args->ar_errors != GFS2_ERRORS_DEFAULT) {
1363                 const char *state;
1364
1365                 switch (args->ar_errors) {
1366                 case GFS2_ERRORS_WITHDRAW:
1367                         state = "withdraw";
1368                         break;
1369                 case GFS2_ERRORS_PANIC:
1370                         state = "panic";
1371                         break;
1372                 default:
1373                         state = "unknown";
1374                         break;
1375                 }
1376                 seq_printf(s, ",errors=%s", state);
1377         }
1378         if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags))
1379                 seq_puts(s, ",nobarrier");
1380         if (test_bit(SDF_DEMOTE, &sdp->sd_flags))
1381                 seq_puts(s, ",demote_interface_used");
1382         if (args->ar_rgrplvb)
1383                 seq_puts(s, ",rgrplvb");
1384         return 0;
1385 }
1386
1387 static void gfs2_final_release_pages(struct gfs2_inode *ip)
1388 {
1389         struct inode *inode = &ip->i_inode;
1390         struct gfs2_glock *gl = ip->i_gl;
1391
1392         truncate_inode_pages(gfs2_glock2aspace(ip->i_gl), 0);
1393         truncate_inode_pages(&inode->i_data, 0);
1394
1395         if (atomic_read(&gl->gl_revokes) == 0) {
1396                 clear_bit(GLF_LFLUSH, &gl->gl_flags);
1397                 clear_bit(GLF_DIRTY, &gl->gl_flags);
1398         }
1399 }
1400
1401 static int gfs2_dinode_dealloc(struct gfs2_inode *ip)
1402 {
1403         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1404         struct gfs2_rgrpd *rgd;
1405         struct gfs2_holder gh;
1406         int error;
1407
1408         if (gfs2_get_inode_blocks(&ip->i_inode) != 1) {
1409                 gfs2_consist_inode(ip);
1410                 return -EIO;
1411         }
1412
1413         error = gfs2_rindex_update(sdp);
1414         if (error)
1415                 return error;
1416
1417         error = gfs2_quota_hold(ip, NO_UID_QUOTA_CHANGE, NO_GID_QUOTA_CHANGE);
1418         if (error)
1419                 return error;
1420
1421         rgd = gfs2_blk2rgrpd(sdp, ip->i_no_addr, 1);
1422         if (!rgd) {
1423                 gfs2_consist_inode(ip);
1424                 error = -EIO;
1425                 goto out_qs;
1426         }
1427
1428         error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, &gh);
1429         if (error)
1430                 goto out_qs;
1431
1432         error = gfs2_trans_begin(sdp, RES_RG_BIT + RES_STATFS + RES_QUOTA,
1433                                  sdp->sd_jdesc->jd_blocks);
1434         if (error)
1435                 goto out_rg_gunlock;
1436
1437         gfs2_free_di(rgd, ip);
1438
1439         gfs2_final_release_pages(ip);
1440
1441         gfs2_trans_end(sdp);
1442
1443 out_rg_gunlock:
1444         gfs2_glock_dq_uninit(&gh);
1445 out_qs:
1446         gfs2_quota_unhold(ip);
1447         return error;
1448 }
1449
1450 /**
1451  * gfs2_evict_inode - Remove an inode from cache
1452  * @inode: The inode to evict
1453  *
1454  * There are three cases to consider:
1455  * 1. i_nlink == 0, we are final opener (and must deallocate)
1456  * 2. i_nlink == 0, we are not the final opener (and cannot deallocate)
1457  * 3. i_nlink > 0
1458  *
1459  * If the fs is read only, then we have to treat all cases as per #3
1460  * since we are unable to do any deallocation. The inode will be
1461  * deallocated by the next read/write node to attempt an allocation
1462  * in the same resource group
1463  *
1464  * We have to (at the moment) hold the inodes main lock to cover
1465  * the gap between unlocking the shared lock on the iopen lock and
1466  * taking the exclusive lock. I'd rather do a shared -> exclusive
1467  * conversion on the iopen lock, but we can change that later. This
1468  * is safe, just less efficient.
1469  */
1470
1471 static void gfs2_evict_inode(struct inode *inode)
1472 {
1473         struct super_block *sb = inode->i_sb;
1474         struct gfs2_sbd *sdp = sb->s_fs_info;
1475         struct gfs2_inode *ip = GFS2_I(inode);
1476         struct gfs2_holder gh;
1477         int error;
1478
1479         if (test_bit(GIF_FREE_VFS_INODE, &ip->i_flags)) {
1480                 clear_inode(inode);
1481                 return;
1482         }
1483
1484         if (inode->i_nlink || (sb->s_flags & MS_RDONLY))
1485                 goto out;
1486
1487         /* Must not read inode block until block type has been verified */
1488         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_SKIP, &gh);
1489         if (unlikely(error)) {
1490                 ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
1491                 gfs2_glock_dq_uninit(&ip->i_iopen_gh);
1492                 goto out;
1493         }
1494
1495         if (!test_bit(GIF_ALLOC_FAILED, &ip->i_flags)) {
1496                 error = gfs2_check_blk_type(sdp, ip->i_no_addr, GFS2_BLKST_UNLINKED);
1497                 if (error)
1498                         goto out_truncate;
1499         }
1500
1501         if (test_bit(GIF_INVALID, &ip->i_flags)) {
1502                 error = gfs2_inode_refresh(ip);
1503                 if (error)
1504                         goto out_truncate;
1505         }
1506
1507         ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
1508         gfs2_glock_dq_wait(&ip->i_iopen_gh);
1509         gfs2_holder_reinit(LM_ST_EXCLUSIVE, LM_FLAG_TRY_1CB | GL_NOCACHE, &ip->i_iopen_gh);
1510         error = gfs2_glock_nq(&ip->i_iopen_gh);
1511         if (error)
1512                 goto out_truncate;
1513
1514         /* Case 1 starts here */
1515
1516         if (S_ISDIR(inode->i_mode) &&
1517             (ip->i_diskflags & GFS2_DIF_EXHASH)) {
1518                 error = gfs2_dir_exhash_dealloc(ip);
1519                 if (error)
1520                         goto out_unlock;
1521         }
1522
1523         if (ip->i_eattr) {
1524                 error = gfs2_ea_dealloc(ip);
1525                 if (error)
1526                         goto out_unlock;
1527         }
1528
1529         if (!gfs2_is_stuffed(ip)) {
1530                 error = gfs2_file_dealloc(ip);
1531                 if (error)
1532                         goto out_unlock;
1533         }
1534
1535         error = gfs2_dinode_dealloc(ip);
1536         goto out_unlock;
1537
1538 out_truncate:
1539         gfs2_log_flush(sdp, ip->i_gl, NORMAL_FLUSH);
1540         if (test_bit(GLF_DIRTY, &ip->i_gl->gl_flags)) {
1541                 struct address_space *metamapping = gfs2_glock2aspace(ip->i_gl);
1542                 filemap_fdatawrite(metamapping);
1543                 filemap_fdatawait(metamapping);
1544         }
1545         write_inode_now(inode, 1);
1546         gfs2_ail_flush(ip->i_gl, 0);
1547
1548         /* Case 2 starts here */
1549         error = gfs2_trans_begin(sdp, 0, sdp->sd_jdesc->jd_blocks);
1550         if (error)
1551                 goto out_unlock;
1552         /* Needs to be done before glock release & also in a transaction */
1553         truncate_inode_pages(&inode->i_data, 0);
1554         gfs2_trans_end(sdp);
1555
1556 out_unlock:
1557         /* Error path for case 1 */
1558         if (gfs2_rs_active(ip->i_res))
1559                 gfs2_rs_deltree(ip->i_res);
1560
1561         if (test_bit(HIF_HOLDER, &ip->i_iopen_gh.gh_iflags)) {
1562                 ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
1563                 gfs2_glock_dq(&ip->i_iopen_gh);
1564         }
1565         gfs2_holder_uninit(&ip->i_iopen_gh);
1566         gfs2_glock_dq_uninit(&gh);
1567         if (error && error != GLR_TRYFAILED && error != -EROFS)
1568                 fs_warn(sdp, "gfs2_evict_inode: %d\n", error);
1569 out:
1570         /* Case 3 starts here */
1571         truncate_inode_pages_final(&inode->i_data);
1572         gfs2_rs_delete(ip, NULL);
1573         gfs2_ordered_del_inode(ip);
1574         clear_inode(inode);
1575         gfs2_dir_hash_inval(ip);
1576         ip->i_gl->gl_object = NULL;
1577         flush_delayed_work(&ip->i_gl->gl_work);
1578         gfs2_glock_add_to_lru(ip->i_gl);
1579         gfs2_glock_put(ip->i_gl);
1580         ip->i_gl = NULL;
1581         if (ip->i_iopen_gh.gh_gl) {
1582                 ip->i_iopen_gh.gh_gl->gl_object = NULL;
1583                 ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
1584                 gfs2_glock_dq_uninit(&ip->i_iopen_gh);
1585         }
1586 }
1587
1588 static struct inode *gfs2_alloc_inode(struct super_block *sb)
1589 {
1590         struct gfs2_inode *ip;
1591
1592         ip = kmem_cache_alloc(gfs2_inode_cachep, GFP_KERNEL);
1593         if (ip) {
1594                 ip->i_flags = 0;
1595                 ip->i_gl = NULL;
1596                 ip->i_rgd = NULL;
1597                 ip->i_res = NULL;
1598         }
1599         return &ip->i_inode;
1600 }
1601
1602 static void gfs2_i_callback(struct rcu_head *head)
1603 {
1604         struct inode *inode = container_of(head, struct inode, i_rcu);
1605         kmem_cache_free(gfs2_inode_cachep, inode);
1606 }
1607
1608 static void gfs2_destroy_inode(struct inode *inode)
1609 {
1610         call_rcu(&inode->i_rcu, gfs2_i_callback);
1611 }
1612
1613 const struct super_operations gfs2_super_ops = {
1614         .alloc_inode            = gfs2_alloc_inode,
1615         .destroy_inode          = gfs2_destroy_inode,
1616         .write_inode            = gfs2_write_inode,
1617         .dirty_inode            = gfs2_dirty_inode,
1618         .evict_inode            = gfs2_evict_inode,
1619         .put_super              = gfs2_put_super,
1620         .sync_fs                = gfs2_sync_fs,
1621         .freeze_fs              = gfs2_freeze,
1622         .unfreeze_fs            = gfs2_unfreeze,
1623         .statfs                 = gfs2_statfs,
1624         .remount_fs             = gfs2_remount_fs,
1625         .drop_inode             = gfs2_drop_inode,
1626         .show_options           = gfs2_show_options,
1627 };
1628