fs/gfs2/super.c

   1 /*
   2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3  * Copyright (C) 2004-2005 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 v.2.
   8  */
   9
  10 #include <linux/sched.h>
  11 #include <linux/slab.h>
  12 #include <linux/spinlock.h>
  13 #include <linux/completion.h>
  14 #include <linux/buffer_head.h>
  15 #include <linux/crc32.h>
  16 #include <linux/gfs2_ondisk.h>
  17 #include <asm/semaphore.h>
  18
  19 #include "gfs2.h"
  20 #include "lm_interface.h"
  21 #include "incore.h"
  22 #include "bmap.h"
  23 #include "dir.h"
  24 #include "format.h"
  25 #include "glock.h"
  26 #include "glops.h"
  27 #include "inode.h"
  28 #include "log.h"
  29 #include "meta_io.h"
  30 #include "quota.h"
  31 #include "recovery.h"
  32 #include "rgrp.h"
  33 #include "super.h"
  34 #include "trans.h"
  35 #include "unlinked.h"
  36 #include "util.h"
  37
  38 /**
  39  * gfs2_tune_init - Fill a gfs2_tune structure with default values
  40  * @gt: tune
  41  *
  42  */
  43
  44 void gfs2_tune_init(struct gfs2_tune *gt)
  45 {
  46         spin_lock_init(&gt->gt_spin);
  47
  48         gt->gt_ilimit = 100;
  49         gt->gt_ilimit_tries = 3;
  50         gt->gt_ilimit_min = 1;
  51         gt->gt_demote_secs = 300;
  52         gt->gt_incore_log_blocks = 1024;
  53         gt->gt_log_flush_secs = 60;
  54         gt->gt_jindex_refresh_secs = 60;
  55         gt->gt_scand_secs = 15;
  56         gt->gt_recoverd_secs = 60;
  57         gt->gt_logd_secs = 1;
  58         gt->gt_quotad_secs = 5;
  59         gt->gt_inoded_secs = 15;
  60         gt->gt_quota_simul_sync = 64;
  61         gt->gt_quota_warn_period = 10;
  62         gt->gt_quota_scale_num = 1;
  63         gt->gt_quota_scale_den = 1;
  64         gt->gt_quota_cache_secs = 300;
  65         gt->gt_quota_quantum = 60;
  66         gt->gt_atime_quantum = 3600;
  67         gt->gt_new_files_jdata = 0;
  68         gt->gt_new_files_directio = 0;
  69         gt->gt_max_atomic_write = 4 << 20;
  70         gt->gt_max_readahead = 1 << 18;
  71         gt->gt_lockdump_size = 131072;
  72         gt->gt_stall_secs = 600;
  73         gt->gt_complain_secs = 10;
  74         gt->gt_reclaim_limit = 5000;
  75         gt->gt_entries_per_readdir = 32;
  76         gt->gt_prefetch_secs = 10;
  77         gt->gt_greedy_default = HZ / 10;
  78         gt->gt_greedy_quantum = HZ / 40;
  79         gt->gt_greedy_max = HZ / 4;
  80         gt->gt_statfs_quantum = 30;
  81         gt->gt_statfs_slow = 0;
  82 }
  83
  84 /**
  85  * gfs2_check_sb - Check superblock
  86  * @sdp: the filesystem
  87  * @sb: The superblock
  88  * @silent: Don't print a message if the check fails
  89  *
  90  * Checks the version code of the FS is one that we understand how to
  91  * read and that the sizes of the various on-disk structures have not
  92  * changed.
  93  */
  94
  95 int gfs2_check_sb(struct gfs2_sbd *sdp, struct gfs2_sb *sb, int silent)
  96 {
  97         unsigned int x;
  98
  99         if (sb->sb_header.mh_magic != GFS2_MAGIC ||
 100             sb->sb_header.mh_type != GFS2_METATYPE_SB) {
 101                 if (!silent)
 102                         printk(KERN_WARNING "GFS2: not a GFS2 filesystem\n");
 103                 return -EINVAL;
 104         }
 105
 106         /*  If format numbers match exactly, we're done.  */
 107
 108         if (sb->sb_fs_format == GFS2_FORMAT_FS &&
 109             sb->sb_multihost_format == GFS2_FORMAT_MULTI)
 110                 return 0;
 111
 112         if (sb->sb_fs_format != GFS2_FORMAT_FS) {
 113                 for (x = 0; gfs2_old_fs_formats[x]; x++)
 114                         if (gfs2_old_fs_formats[x] == sb->sb_fs_format)
 115                                 break;
 116
 117                 if (!gfs2_old_fs_formats[x]) {
 118                         printk(KERN_WARNING
 119                                "GFS2: code version (%u, %u) is incompatible "
 120                                "with ondisk format (%u, %u)\n",
 121                                GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
 122                                sb->sb_fs_format, sb->sb_multihost_format);
 123                         printk(KERN_WARNING
 124                                "GFS2: I don't know how to upgrade this FS\n");
 125                         return -EINVAL;
 126                 }
 127         }
 128
 129         if (sb->sb_multihost_format != GFS2_FORMAT_MULTI) {
 130                 for (x = 0; gfs2_old_multihost_formats[x]; x++)
 131                         if (gfs2_old_multihost_formats[x] ==
 132                             sb->sb_multihost_format)
 133                                 break;
 134
 135                 if (!gfs2_old_multihost_formats[x]) {
 136                         printk(KERN_WARNING
 137                                "GFS2: code version (%u, %u) is incompatible "
 138                                "with ondisk format (%u, %u)\n",
 139                                GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
 140                                sb->sb_fs_format, sb->sb_multihost_format);
 141                         printk(KERN_WARNING
 142                                "GFS2: I don't know how to upgrade this FS\n");
 143                         return -EINVAL;
 144                 }
 145         }
 146
 147         if (!sdp->sd_args.ar_upgrade) {
 148                 printk(KERN_WARNING
 149                        "GFS2: code version (%u, %u) is incompatible "
 150                        "with ondisk format (%u, %u)\n",
 151                        GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
 152                        sb->sb_fs_format, sb->sb_multihost_format);
 153                 printk(KERN_INFO
 154                        "GFS2: Use the \"upgrade\" mount option to upgrade "
 155                        "the FS\n");
 156                 printk(KERN_INFO "GFS2: See the manual for more details\n");
 157                 return -EINVAL;
 158         }
 159
 160         return 0;
 161 }
 162
 163 /**
 164  * gfs2_read_sb - Read super block
 165  * @sdp: The GFS2 superblock
 166  * @gl: the glock for the superblock (assumed to be held)
 167  * @silent: Don't print message if mount fails
 168  *
 169  */
 170
 171 int gfs2_read_sb(struct gfs2_sbd *sdp, struct gfs2_glock *gl, int silent)
 172 {
 173         struct buffer_head *bh;
 174         uint32_t hash_blocks, ind_blocks, leaf_blocks;
 175         uint32_t tmp_blocks;
 176         unsigned int x;
 177         int error;
 178
 179         error = gfs2_meta_read(gl, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift,
 180                                DIO_FORCE | DIO_START | DIO_WAIT, &bh);
 181         if (error) {
 182                 if (!silent)
 183                         fs_err(sdp, "can't read superblock\n");
 184                 return error;
 185         }
 186
 187         gfs2_assert(sdp, sizeof(struct gfs2_sb) <= bh->b_size);
 188         gfs2_sb_in(&sdp->sd_sb, bh->b_data);
 189         brelse(bh);
 190
 191         error = gfs2_check_sb(sdp, &sdp->sd_sb, silent);
 192         if (error)
 193                 return error;
 194
 195         sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
 196                                GFS2_BASIC_BLOCK_SHIFT;
 197         sdp->sd_fsb2bb = 1 << sdp->sd_fsb2bb_shift;
 198         sdp->sd_diptrs = (sdp->sd_sb.sb_bsize -
 199                           sizeof(struct gfs2_dinode)) / sizeof(uint64_t);
 200         sdp->sd_inptrs = (sdp->sd_sb.sb_bsize -
 201                           sizeof(struct gfs2_meta_header)) / sizeof(uint64_t);
 202         sdp->sd_jbsize = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header);
 203         sdp->sd_hash_bsize = sdp->sd_sb.sb_bsize / 2;
 204         sdp->sd_hash_bsize_shift = sdp->sd_sb.sb_bsize_shift - 1;
 205         sdp->sd_hash_ptrs = sdp->sd_hash_bsize / sizeof(uint64_t);
 206         sdp->sd_ut_per_block = (sdp->sd_sb.sb_bsize -
 207                                 sizeof(struct gfs2_meta_header)) /
 208                                sizeof(struct gfs2_unlinked_tag);
 209         sdp->sd_qc_per_block = (sdp->sd_sb.sb_bsize -
 210                                 sizeof(struct gfs2_meta_header)) /
 211                                sizeof(struct gfs2_quota_change);
 212
 213         /* Compute maximum reservation required to add a entry to a directory */
 214
 215         hash_blocks = DIV_ROUND_UP(sizeof(uint64_t) * (1 << GFS2_DIR_MAX_DEPTH),
 216                              sdp->sd_jbsize);
 217
 218         ind_blocks = 0;
 219         for (tmp_blocks = hash_blocks; tmp_blocks > sdp->sd_diptrs;) {
 220                 tmp_blocks = DIV_ROUND_UP(tmp_blocks, sdp->sd_inptrs);
 221                 ind_blocks += tmp_blocks;
 222         }
 223
 224         leaf_blocks = 2 + GFS2_DIR_MAX_DEPTH;
 225
 226         sdp->sd_max_dirres = hash_blocks + ind_blocks + leaf_blocks;
 227
 228         sdp->sd_heightsize[0] = sdp->sd_sb.sb_bsize -
 229                                 sizeof(struct gfs2_dinode);
 230         sdp->sd_heightsize[1] = sdp->sd_sb.sb_bsize * sdp->sd_diptrs;
 231         for (x = 2;; x++) {
 232                 uint64_t space, d;
 233                 uint32_t m;
 234
 235                 space = sdp->sd_heightsize[x - 1] * sdp->sd_inptrs;
 236                 d = space;
 237                 m = do_div(d, sdp->sd_inptrs);
 238
 239                 if (d != sdp->sd_heightsize[x - 1] || m)
 240                         break;
 241                 sdp->sd_heightsize[x] = space;
 242         }
 243         sdp->sd_max_height = x;
 244         gfs2_assert(sdp, sdp->sd_max_height <= GFS2_MAX_META_HEIGHT);
 245
 246         sdp->sd_jheightsize[0] = sdp->sd_sb.sb_bsize -
 247                                  sizeof(struct gfs2_dinode);
 248         sdp->sd_jheightsize[1] = sdp->sd_jbsize * sdp->sd_diptrs;
 249         for (x = 2;; x++) {
 250                 uint64_t space, d;
 251                 uint32_t m;
 252
 253                 space = sdp->sd_jheightsize[x - 1] * sdp->sd_inptrs;
 254                 d = space;
 255                 m = do_div(d, sdp->sd_inptrs);
 256
 257                 if (d != sdp->sd_jheightsize[x - 1] || m)
 258                         break;
 259                 sdp->sd_jheightsize[x] = space;
 260         }
 261         sdp->sd_max_jheight = x;
 262         gfs2_assert(sdp, sdp->sd_max_jheight <= GFS2_MAX_META_HEIGHT);
 263
 264         return 0;
 265 }
 266
 267 int gfs2_do_upgrade(struct gfs2_sbd *sdp, struct gfs2_glock *sb_gl)
 268 {
 269         return 0;
 270 }
 271
 272 /**
 273  * gfs2_jindex_hold - Grab a lock on the jindex
 274  * @sdp: The GFS2 superblock
 275  * @ji_gh: the holder for the jindex glock
 276  *
 277  * This is very similar to the gfs2_rindex_hold() function, except that
 278  * in general we hold the jindex lock for longer periods of time and
 279  * we grab it far less frequently (in general) then the rgrp lock.
 280  *
 281  * Returns: errno
 282  */
 283
 284 int gfs2_jindex_hold(struct gfs2_sbd *sdp, struct gfs2_holder *ji_gh)
 285 {
 286         struct gfs2_inode *dip = sdp->sd_jindex->u.generic_ip;
 287         struct qstr name;
 288         char buf[20];
 289         struct gfs2_jdesc *jd;
 290         int error;
 291
 292         name.name = buf;
 293
 294         mutex_lock(&sdp->sd_jindex_mutex);
 295
 296         for (;;) {
 297                 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED,
 298                                            GL_LOCAL_EXCL, ji_gh);
 299                 if (error)
 300                         break;
 301
 302                 name.len = sprintf(buf, "journal%u", sdp->sd_journals);
 303                 name.hash = gfs2_disk_hash(name.name, name.len);
 304
 305                 error = gfs2_dir_search(sdp->sd_jindex,
 306                                         &name, NULL, NULL);
 307                 if (error == -ENOENT) {
 308                         error = 0;
 309                         break;
 310                 }
 311
 312                 gfs2_glock_dq_uninit(ji_gh);
 313
 314                 if (error)
 315                         break;
 316
 317                 error = -ENOMEM;
 318                 jd = kzalloc(sizeof(struct gfs2_jdesc), GFP_KERNEL);
 319                 if (!jd)
 320                         break;
 321
 322                 jd->jd_inode = gfs2_lookupi(sdp->sd_jindex, &name, 1, NULL);
 323                 if (!jd->jd_inode || IS_ERR(jd->jd_inode)) {
 324                         if (!jd->jd_inode)
 325                                 error = -ENOENT;
 326                         else
 327                                 error = PTR_ERR(jd->jd_inode);
 328                         kfree(jd);
 329                         break;
 330                 }
 331
 332                 spin_lock(&sdp->sd_jindex_spin);
 333                 jd->jd_jid = sdp->sd_journals++;
 334                 list_add_tail(&jd->jd_list, &sdp->sd_jindex_list);
 335                 spin_unlock(&sdp->sd_jindex_spin);
 336         }
 337
 338         mutex_unlock(&sdp->sd_jindex_mutex);
 339
 340         return error;
 341 }
 342
 343 /**
 344  * gfs2_jindex_free - Clear all the journal index information
 345  * @sdp: The GFS2 superblock
 346  *
 347  */
 348
 349 void gfs2_jindex_free(struct gfs2_sbd *sdp)
 350 {
 351         struct list_head list;
 352         struct gfs2_jdesc *jd;
 353
 354         spin_lock(&sdp->sd_jindex_spin);
 355         list_add(&list, &sdp->sd_jindex_list);
 356         list_del_init(&sdp->sd_jindex_list);
 357         sdp->sd_journals = 0;
 358         spin_unlock(&sdp->sd_jindex_spin);
 359
 360         while (!list_empty(&list)) {
 361                 jd = list_entry(list.next, struct gfs2_jdesc, jd_list);
 362                 list_del(&jd->jd_list);
 363                 iput(jd->jd_inode);
 364                 kfree(jd);
 365         }
 366 }
 367
 368 static struct gfs2_jdesc *jdesc_find_i(struct list_head *head, unsigned int jid)
 369 {
 370         struct gfs2_jdesc *jd;
 371         int found = 0;
 372
 373         list_for_each_entry(jd, head, jd_list) {
 374                 if (jd->jd_jid == jid) {
 375                         found = 1;
 376                         break;
 377                 }
 378         }
 379
 380         if (!found)
 381                 jd = NULL;
 382
 383         return jd;
 384 }
 385
 386 struct gfs2_jdesc *gfs2_jdesc_find(struct gfs2_sbd *sdp, unsigned int jid)
 387 {
 388         struct gfs2_jdesc *jd;
 389
 390         spin_lock(&sdp->sd_jindex_spin);
 391         jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
 392         spin_unlock(&sdp->sd_jindex_spin);
 393
 394         return jd;
 395 }
 396
 397 void gfs2_jdesc_make_dirty(struct gfs2_sbd *sdp, unsigned int jid)
 398 {
 399         struct gfs2_jdesc *jd;
 400
 401         spin_lock(&sdp->sd_jindex_spin);
 402         jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
 403         if (jd)
 404                 jd->jd_dirty = 1;
 405         spin_unlock(&sdp->sd_jindex_spin);
 406 }
 407
 408 struct gfs2_jdesc *gfs2_jdesc_find_dirty(struct gfs2_sbd *sdp)
 409 {
 410         struct gfs2_jdesc *jd;
 411         int found = 0;
 412
 413         spin_lock(&sdp->sd_jindex_spin);
 414
 415         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 416                 if (jd->jd_dirty) {
 417                         jd->jd_dirty = 0;
 418                         found = 1;
 419                         break;
 420                 }
 421         }
 422         spin_unlock(&sdp->sd_jindex_spin);
 423
 424         if (!found)
 425                 jd = NULL;
 426
 427         return jd;
 428 }
 429
 430 int gfs2_jdesc_check(struct gfs2_jdesc *jd)
 431 {
 432         struct gfs2_inode *ip = jd->jd_inode->u.generic_ip;
 433         struct gfs2_sbd *sdp = ip->i_sbd;
 434         int ar;
 435         int error;
 436
 437         if (ip->i_di.di_size < (8 << 20) ||
 438             ip->i_di.di_size > (1 << 30) ||
 439             (ip->i_di.di_size & (sdp->sd_sb.sb_bsize - 1))) {
 440                 gfs2_consist_inode(ip);
 441                 return -EIO;
 442         }
 443         jd->jd_blocks = ip->i_di.di_size >> sdp->sd_sb.sb_bsize_shift;
 444
 445         error = gfs2_write_alloc_required(ip,
 446                                           0, ip->i_di.di_size,
 447                                           &ar);
 448         if (!error && ar) {
 449                 gfs2_consist_inode(ip);
 450                 error = -EIO;
 451         }
 452
 453         return error;
 454 }
 455
 456 /**
 457  * gfs2_make_fs_rw - Turn a Read-Only FS into a Read-Write one
 458  * @sdp: the filesystem
 459  *
 460  * Returns: errno
 461  */
 462
 463 int gfs2_make_fs_rw(struct gfs2_sbd *sdp)
 464 {
 465         struct gfs2_inode *ip = sdp->sd_jdesc->jd_inode->u.generic_ip;
 466         struct gfs2_glock *j_gl = ip->i_gl;
 467         struct gfs2_holder t_gh;
 468         struct gfs2_log_header head;
 469         int error;
 470
 471         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
 472                                    GL_LOCAL_EXCL, &t_gh);
 473         if (error)
 474                 return error;
 475
 476         gfs2_meta_cache_flush(ip);
 477         j_gl->gl_ops->go_inval(j_gl, DIO_METADATA | DIO_DATA);
 478
 479         error = gfs2_find_jhead(sdp->sd_jdesc, &head);
 480         if (error)
 481                 goto fail;
 482
 483         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 484                 gfs2_consist(sdp);
 485                 error = -EIO;
 486                 goto fail;
 487         }
 488
 489         /*  Initialize some head of the log stuff  */
 490         sdp->sd_log_sequence = head.lh_sequence + 1;
 491         gfs2_log_pointers_init(sdp, head.lh_blkno);
 492
 493         error = gfs2_unlinked_init(sdp);
 494         if (error)
 495                 goto fail;
 496         error = gfs2_quota_init(sdp);
 497         if (error)
 498                 goto fail_unlinked;
 499
 500         set_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 501
 502         gfs2_glock_dq_uninit(&t_gh);
 503
 504         return 0;
 505
 506  fail_unlinked:
 507         gfs2_unlinked_cleanup(sdp);
 508
 509  fail:
 510         t_gh.gh_flags |= GL_NOCACHE;
 511         gfs2_glock_dq_uninit(&t_gh);
 512
 513         return error;
 514 }
 515
 516 /**
 517  * gfs2_make_fs_ro - Turn a Read-Write FS into a Read-Only one
 518  * @sdp: the filesystem
 519  *
 520  * Returns: errno
 521  */
 522
 523 int gfs2_make_fs_ro(struct gfs2_sbd *sdp)
 524 {
 525         struct gfs2_holder t_gh;
 526         int error;
 527
 528         gfs2_unlinked_dealloc(sdp);
 529         gfs2_quota_sync(sdp);
 530         gfs2_statfs_sync(sdp);
 531
 532         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
 533                                 GL_LOCAL_EXCL | GL_NOCACHE,
 534                                 &t_gh);
 535         if (error && !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
 536                 return error;
 537
 538         gfs2_meta_syncfs(sdp);
 539         gfs2_log_shutdown(sdp);
 540
 541         clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 542
 543         if (t_gh.gh_gl)
 544                 gfs2_glock_dq_uninit(&t_gh);
 545
 546         gfs2_unlinked_cleanup(sdp);
 547         gfs2_quota_cleanup(sdp);
 548
 549         return error;
 550 }
 551
 552 int gfs2_statfs_init(struct gfs2_sbd *sdp)
 553 {
 554         struct gfs2_inode *m_ip = sdp->sd_statfs_inode->u.generic_ip;
 555         struct gfs2_statfs_change *m_sc = &sdp->sd_statfs_master;
 556         struct gfs2_inode *l_ip = sdp->sd_sc_inode->u.generic_ip;
 557         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 558         struct buffer_head *m_bh, *l_bh;
 559         struct gfs2_holder gh;
 560         int error;
 561
 562         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 563                                    &gh);
 564         if (error)
 565                 return error;
 566
 567         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 568         if (error)
 569                 goto out;
 570
 571         if (sdp->sd_args.ar_spectator) {
 572                 spin_lock(&sdp->sd_statfs_spin);
 573                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 574                                       sizeof(struct gfs2_dinode));
 575                 spin_unlock(&sdp->sd_statfs_spin);
 576         } else {
 577                 error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 578                 if (error)
 579                         goto out_m_bh;
 580
 581                 spin_lock(&sdp->sd_statfs_spin);
 582                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 583                                       sizeof(struct gfs2_dinode));
 584                 gfs2_statfs_change_in(l_sc, l_bh->b_data +
 585                                       sizeof(struct gfs2_dinode));
 586                 spin_unlock(&sdp->sd_statfs_spin);
 587
 588                 brelse(l_bh);
 589         }
 590
 591  out_m_bh:
 592         brelse(m_bh);
 593
 594  out:
 595         gfs2_glock_dq_uninit(&gh);
 596
 597         return 0;
 598 }
 599
 600 void gfs2_statfs_change(struct gfs2_sbd *sdp, int64_t total, int64_t free,
 601                         int64_t dinodes)
 602 {
 603         struct gfs2_inode *l_ip = sdp->sd_sc_inode->u.generic_ip;
 604         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 605         struct buffer_head *l_bh;
 606         int error;
 607
 608         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 609         if (error)
 610                 return;
 611
 612         mutex_lock(&sdp->sd_statfs_mutex);
 613         gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
 614         mutex_unlock(&sdp->sd_statfs_mutex);
 615
 616         spin_lock(&sdp->sd_statfs_spin);
 617         l_sc->sc_total += total;
 618         l_sc->sc_free += free;
 619         l_sc->sc_dinodes += dinodes;
 620         gfs2_statfs_change_out(l_sc, l_bh->b_data +
 621                                sizeof(struct gfs2_dinode));
 622         spin_unlock(&sdp->sd_statfs_spin);
 623
 624         brelse(l_bh);
 625 }
 626
 627 int gfs2_statfs_sync(struct gfs2_sbd *sdp)
 628 {
 629         struct gfs2_inode *m_ip = sdp->sd_statfs_inode->u.generic_ip;
 630         struct gfs2_inode *l_ip = sdp->sd_sc_inode->u.generic_ip;
 631         struct gfs2_statfs_change *m_sc = &sdp->sd_statfs_master;
 632         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 633         struct gfs2_holder gh;
 634         struct buffer_head *m_bh, *l_bh;
 635         int error;
 636
 637         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 638                                    &gh);
 639         if (error)
 640                 return error;
 641
 642         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 643         if (error)
 644                 goto out;
 645
 646         spin_lock(&sdp->sd_statfs_spin);
 647         gfs2_statfs_change_in(m_sc, m_bh->b_data +
 648                               sizeof(struct gfs2_dinode));
 649         if (!l_sc->sc_total && !l_sc->sc_free && !l_sc->sc_dinodes) {
 650                 spin_unlock(&sdp->sd_statfs_spin);
 651                 goto out_bh;
 652         }
 653         spin_unlock(&sdp->sd_statfs_spin);
 654
 655         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 656         if (error)
 657                 goto out_bh;
 658
 659         error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
 660         if (error)
 661                 goto out_bh2;
 662
 663         mutex_lock(&sdp->sd_statfs_mutex);
 664         gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
 665         mutex_unlock(&sdp->sd_statfs_mutex);
 666
 667         spin_lock(&sdp->sd_statfs_spin);
 668         m_sc->sc_total += l_sc->sc_total;
 669         m_sc->sc_free += l_sc->sc_free;
 670         m_sc->sc_dinodes += l_sc->sc_dinodes;
 671         memset(l_sc, 0, sizeof(struct gfs2_statfs_change));
 672         memset(l_bh->b_data + sizeof(struct gfs2_dinode),
 673                0, sizeof(struct gfs2_statfs_change));
 674         spin_unlock(&sdp->sd_statfs_spin);
 675
 676         gfs2_trans_add_bh(m_ip->i_gl, m_bh, 1);
 677         gfs2_statfs_change_out(m_sc, m_bh->b_data + sizeof(struct gfs2_dinode));
 678
 679         gfs2_trans_end(sdp);
 680
 681  out_bh2:
 682         brelse(l_bh);
 683
 684  out_bh:
 685         brelse(m_bh);
 686
 687  out:
 688         gfs2_glock_dq_uninit(&gh);
 689
 690         return error;
 691 }
 692
 693 /**
 694  * gfs2_statfs_i - Do a statfs
 695  * @sdp: the filesystem
 696  * @sg: the sg structure
 697  *
 698  * Returns: errno
 699  */
 700
 701 int gfs2_statfs_i(struct gfs2_sbd *sdp, struct gfs2_statfs_change *sc)
 702 {
 703         struct gfs2_statfs_change *m_sc = &sdp->sd_statfs_master;
 704         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 705
 706         spin_lock(&sdp->sd_statfs_spin);
 707
 708         *sc = *m_sc;
 709         sc->sc_total += l_sc->sc_total;
 710         sc->sc_free += l_sc->sc_free;
 711         sc->sc_dinodes += l_sc->sc_dinodes;
 712
 713         spin_unlock(&sdp->sd_statfs_spin);
 714
 715         if (sc->sc_free < 0)
 716                 sc->sc_free = 0;
 717         if (sc->sc_free > sc->sc_total)
 718                 sc->sc_free = sc->sc_total;
 719         if (sc->sc_dinodes < 0)
 720                 sc->sc_dinodes = 0;
 721
 722         return 0;
 723 }
 724
 725 /**
 726  * statfs_fill - fill in the sg for a given RG
 727  * @rgd: the RG
 728  * @sc: the sc structure
 729  *
 730  * Returns: 0 on success, -ESTALE if the LVB is invalid
 731  */
 732
 733 static int statfs_slow_fill(struct gfs2_rgrpd *rgd,
 734                             struct gfs2_statfs_change *sc)
 735 {
 736         gfs2_rgrp_verify(rgd);
 737         sc->sc_total += rgd->rd_ri.ri_data;
 738         sc->sc_free += rgd->rd_rg.rg_free;
 739         sc->sc_dinodes += rgd->rd_rg.rg_dinodes;
 740         return 0;
 741 }
 742
 743 /**
 744  * gfs2_statfs_slow - Stat a filesystem using asynchronous locking
 745  * @sdp: the filesystem
 746  * @sc: the sc info that will be returned
 747  *
 748  * Any error (other than a signal) will cause this routine to fall back
 749  * to the synchronous version.
 750  *
 751  * FIXME: This really shouldn't busy wait like this.
 752  *
 753  * Returns: errno
 754  */
 755
 756 int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change *sc)
 757 {
 758         struct gfs2_holder ri_gh;
 759         struct gfs2_rgrpd *rgd_next;
 760         struct gfs2_holder *gha, *gh;
 761         unsigned int slots = 64;
 762         unsigned int x;
 763         int done;
 764         int error = 0, err;
 765
 766         memset(sc, 0, sizeof(struct gfs2_statfs_change));
 767         gha = kcalloc(slots, sizeof(struct gfs2_holder), GFP_KERNEL);
 768         if (!gha)
 769                 return -ENOMEM;
 770
 771         error = gfs2_rindex_hold(sdp, &ri_gh);
 772         if (error)
 773                 goto out;
 774
 775         rgd_next = gfs2_rgrpd_get_first(sdp);
 776
 777         for (;;) {
 778                 done = 1;
 779
 780                 for (x = 0; x < slots; x++) {
 781                         gh = gha + x;
 782
 783                         if (gh->gh_gl && gfs2_glock_poll(gh)) {
 784                                 err = gfs2_glock_wait(gh);
 785                                 if (err) {
 786                                         gfs2_holder_uninit(gh);
 787                                         error = err;
 788                                 } else {
 789                                         if (!error)
 790                                                 error = statfs_slow_fill(
 791                                                         gh->gh_gl->gl_object, sc);
 792                                         gfs2_glock_dq_uninit(gh);
 793                                 }
 794                         }
 795
 796                         if (gh->gh_gl)
 797                                 done = 0;
 798                         else if (rgd_next && !error) {
 799                                 error = gfs2_glock_nq_init(rgd_next->rd_gl,
 800                                                            LM_ST_SHARED,
 801                                                            GL_ASYNC,
 802                                                            gh);
 803                                 rgd_next = gfs2_rgrpd_get_next(rgd_next);
 804                                 done = 0;
 805                         }
 806
 807                         if (signal_pending(current))
 808                                 error = -ERESTARTSYS;
 809                 }
 810
 811                 if (done)
 812                         break;
 813
 814                 yield();
 815         }
 816
 817         gfs2_glock_dq_uninit(&ri_gh);
 818
 819  out:
 820         kfree(gha);
 821
 822         return error;
 823 }
 824
 825 struct lfcc {
 826         struct list_head list;
 827         struct gfs2_holder gh;
 828 };
 829
 830 /**
 831  * gfs2_lock_fs_check_clean - Stop all writes to the FS and check that all
 832  *                            journals are clean
 833  * @sdp: the file system
 834  * @state: the state to put the transaction lock into
 835  * @t_gh: the hold on the transaction lock
 836  *
 837  * Returns: errno
 838  */
 839
 840 int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp, struct gfs2_holder *t_gh)
 841 {
 842         struct gfs2_inode *ip;
 843         struct gfs2_holder ji_gh;
 844         struct gfs2_jdesc *jd;
 845         struct lfcc *lfcc;
 846         LIST_HEAD(list);
 847         struct gfs2_log_header lh;
 848         int error;
 849
 850         error = gfs2_jindex_hold(sdp, &ji_gh);
 851         if (error)
 852                 return error;
 853
 854         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 855                 lfcc = kmalloc(sizeof(struct lfcc), GFP_KERNEL);
 856                 if (!lfcc) {
 857                         error = -ENOMEM;
 858                         goto out;
 859                 }
 860                 ip = jd->jd_inode->u.generic_ip;
 861                 error = gfs2_glock_nq_init(ip->i_gl,
 862                                            LM_ST_SHARED, 0,
 863                                            &lfcc->gh);
 864                 if (error) {
 865                         kfree(lfcc);
 866                         goto out;
 867                 }
 868                 list_add(&lfcc->list, &list);
 869         }
 870
 871         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_DEFERRED,
 872                                LM_FLAG_PRIORITY | GL_NOCACHE,
 873                                t_gh);
 874
 875         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 876                 error = gfs2_jdesc_check(jd);
 877                 if (error)
 878                         break;
 879                 error = gfs2_find_jhead(jd, &lh);
 880                 if (error)
 881                         break;
 882                 if (!(lh.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 883                         error = -EBUSY;
 884                         break;
 885                 }
 886         }
 887
 888         if (error)
 889                 gfs2_glock_dq_uninit(t_gh);
 890
 891  out:
 892         while (!list_empty(&list)) {
 893                 lfcc = list_entry(list.next, struct lfcc, list);
 894                 list_del(&lfcc->list);
 895                 gfs2_glock_dq_uninit(&lfcc->gh);
 896                 kfree(lfcc);
 897         }
 898         gfs2_glock_dq_uninit(&ji_gh);
 899
 900         return error;
 901 }
 902
 903 /**
 904  * gfs2_freeze_fs - freezes the file system
 905  * @sdp: the file system
 906  *
 907  * This function flushes data and meta data for all machines by
 908  * aquiring the transaction log exclusively.  All journals are
 909  * ensured to be in a clean state as well.
 910  *
 911  * Returns: errno
 912  */
 913
 914 int gfs2_freeze_fs(struct gfs2_sbd *sdp)
 915 {
 916         int error = 0;
 917
 918         mutex_lock(&sdp->sd_freeze_lock);
 919
 920         if (!sdp->sd_freeze_count++) {
 921                 error = gfs2_lock_fs_check_clean(sdp, &sdp->sd_freeze_gh);
 922                 if (error)
 923                         sdp->sd_freeze_count--;
 924         }
 925
 926         mutex_unlock(&sdp->sd_freeze_lock);
 927
 928         return error;
 929 }
 930
 931 /**
 932  * gfs2_unfreeze_fs - unfreezes the file system
 933  * @sdp: the file system
 934  *
 935  * This function allows the file system to proceed by unlocking
 936  * the exclusively held transaction lock.  Other GFS2 nodes are
 937  * now free to acquire the lock shared and go on with their lives.
 938  *
 939  */
 940
 941 void gfs2_unfreeze_fs(struct gfs2_sbd *sdp)
 942 {
 943         mutex_lock(&sdp->sd_freeze_lock);
 944
 945         if (sdp->sd_freeze_count && !--sdp->sd_freeze_count)
 946                 gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
 947
 948         mutex_unlock(&sdp->sd_freeze_lock);
 949 }
 950