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 /**
 268  * gfs2_jindex_hold - Grab a lock on the jindex
 269  * @sdp: The GFS2 superblock
 270  * @ji_gh: the holder for the jindex glock
 271  *
 272  * This is very similar to the gfs2_rindex_hold() function, except that
 273  * in general we hold the jindex lock for longer periods of time and
 274  * we grab it far less frequently (in general) then the rgrp lock.
 275  *
 276  * Returns: errno
 277  */
 278
 279 int gfs2_jindex_hold(struct gfs2_sbd *sdp, struct gfs2_holder *ji_gh)
 280 {
 281         struct gfs2_inode *dip = sdp->sd_jindex->u.generic_ip;
 282         struct qstr name;
 283         char buf[20];
 284         struct gfs2_jdesc *jd;
 285         int error;
 286
 287         name.name = buf;
 288
 289         mutex_lock(&sdp->sd_jindex_mutex);
 290
 291         for (;;) {
 292                 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED,
 293                                            GL_LOCAL_EXCL, ji_gh);
 294                 if (error)
 295                         break;
 296
 297                 name.len = sprintf(buf, "journal%u", sdp->sd_journals);
 298                 name.hash = gfs2_disk_hash(name.name, name.len);
 299
 300                 error = gfs2_dir_search(sdp->sd_jindex,
 301                                         &name, NULL, NULL);
 302                 if (error == -ENOENT) {
 303                         error = 0;
 304                         break;
 305                 }
 306
 307                 gfs2_glock_dq_uninit(ji_gh);
 308
 309                 if (error)
 310                         break;
 311
 312                 error = -ENOMEM;
 313                 jd = kzalloc(sizeof(struct gfs2_jdesc), GFP_KERNEL);
 314                 if (!jd)
 315                         break;
 316
 317                 jd->jd_inode = gfs2_lookupi(sdp->sd_jindex, &name, 1, NULL);
 318                 if (!jd->jd_inode || IS_ERR(jd->jd_inode)) {
 319                         if (!jd->jd_inode)
 320                                 error = -ENOENT;
 321                         else
 322                                 error = PTR_ERR(jd->jd_inode);
 323                         kfree(jd);
 324                         break;
 325                 }
 326
 327                 spin_lock(&sdp->sd_jindex_spin);
 328                 jd->jd_jid = sdp->sd_journals++;
 329                 list_add_tail(&jd->jd_list, &sdp->sd_jindex_list);
 330                 spin_unlock(&sdp->sd_jindex_spin);
 331         }
 332
 333         mutex_unlock(&sdp->sd_jindex_mutex);
 334
 335         return error;
 336 }
 337
 338 /**
 339  * gfs2_jindex_free - Clear all the journal index information
 340  * @sdp: The GFS2 superblock
 341  *
 342  */
 343
 344 void gfs2_jindex_free(struct gfs2_sbd *sdp)
 345 {
 346         struct list_head list;
 347         struct gfs2_jdesc *jd;
 348
 349         spin_lock(&sdp->sd_jindex_spin);
 350         list_add(&list, &sdp->sd_jindex_list);
 351         list_del_init(&sdp->sd_jindex_list);
 352         sdp->sd_journals = 0;
 353         spin_unlock(&sdp->sd_jindex_spin);
 354
 355         while (!list_empty(&list)) {
 356                 jd = list_entry(list.next, struct gfs2_jdesc, jd_list);
 357                 list_del(&jd->jd_list);
 358                 iput(jd->jd_inode);
 359                 kfree(jd);
 360         }
 361 }
 362
 363 static struct gfs2_jdesc *jdesc_find_i(struct list_head *head, unsigned int jid)
 364 {
 365         struct gfs2_jdesc *jd;
 366         int found = 0;
 367
 368         list_for_each_entry(jd, head, jd_list) {
 369                 if (jd->jd_jid == jid) {
 370                         found = 1;
 371                         break;
 372                 }
 373         }
 374
 375         if (!found)
 376                 jd = NULL;
 377
 378         return jd;
 379 }
 380
 381 struct gfs2_jdesc *gfs2_jdesc_find(struct gfs2_sbd *sdp, unsigned int jid)
 382 {
 383         struct gfs2_jdesc *jd;
 384
 385         spin_lock(&sdp->sd_jindex_spin);
 386         jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
 387         spin_unlock(&sdp->sd_jindex_spin);
 388
 389         return jd;
 390 }
 391
 392 void gfs2_jdesc_make_dirty(struct gfs2_sbd *sdp, unsigned int jid)
 393 {
 394         struct gfs2_jdesc *jd;
 395
 396         spin_lock(&sdp->sd_jindex_spin);
 397         jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
 398         if (jd)
 399                 jd->jd_dirty = 1;
 400         spin_unlock(&sdp->sd_jindex_spin);
 401 }
 402
 403 struct gfs2_jdesc *gfs2_jdesc_find_dirty(struct gfs2_sbd *sdp)
 404 {
 405         struct gfs2_jdesc *jd;
 406         int found = 0;
 407
 408         spin_lock(&sdp->sd_jindex_spin);
 409
 410         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 411                 if (jd->jd_dirty) {
 412                         jd->jd_dirty = 0;
 413                         found = 1;
 414                         break;
 415                 }
 416         }
 417         spin_unlock(&sdp->sd_jindex_spin);
 418
 419         if (!found)
 420                 jd = NULL;
 421
 422         return jd;
 423 }
 424
 425 int gfs2_jdesc_check(struct gfs2_jdesc *jd)
 426 {
 427         struct gfs2_inode *ip = jd->jd_inode->u.generic_ip;
 428         struct gfs2_sbd *sdp = ip->i_sbd;
 429         int ar;
 430         int error;
 431
 432         if (ip->i_di.di_size < (8 << 20) ||
 433             ip->i_di.di_size > (1 << 30) ||
 434             (ip->i_di.di_size & (sdp->sd_sb.sb_bsize - 1))) {
 435                 gfs2_consist_inode(ip);
 436                 return -EIO;
 437         }
 438         jd->jd_blocks = ip->i_di.di_size >> sdp->sd_sb.sb_bsize_shift;
 439
 440         error = gfs2_write_alloc_required(ip,
 441                                           0, ip->i_di.di_size,
 442                                           &ar);
 443         if (!error && ar) {
 444                 gfs2_consist_inode(ip);
 445                 error = -EIO;
 446         }
 447
 448         return error;
 449 }
 450
 451 /**
 452  * gfs2_make_fs_rw - Turn a Read-Only FS into a Read-Write one
 453  * @sdp: the filesystem
 454  *
 455  * Returns: errno
 456  */
 457
 458 int gfs2_make_fs_rw(struct gfs2_sbd *sdp)
 459 {
 460         struct gfs2_inode *ip = sdp->sd_jdesc->jd_inode->u.generic_ip;
 461         struct gfs2_glock *j_gl = ip->i_gl;
 462         struct gfs2_holder t_gh;
 463         struct gfs2_log_header head;
 464         int error;
 465
 466         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
 467                                    GL_LOCAL_EXCL, &t_gh);
 468         if (error)
 469                 return error;
 470
 471         gfs2_meta_cache_flush(ip);
 472         j_gl->gl_ops->go_inval(j_gl, DIO_METADATA | DIO_DATA);
 473
 474         error = gfs2_find_jhead(sdp->sd_jdesc, &head);
 475         if (error)
 476                 goto fail;
 477
 478         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 479                 gfs2_consist(sdp);
 480                 error = -EIO;
 481                 goto fail;
 482         }
 483
 484         /*  Initialize some head of the log stuff  */
 485         sdp->sd_log_sequence = head.lh_sequence + 1;
 486         gfs2_log_pointers_init(sdp, head.lh_blkno);
 487
 488         error = gfs2_unlinked_init(sdp);
 489         if (error)
 490                 goto fail;
 491         error = gfs2_quota_init(sdp);
 492         if (error)
 493                 goto fail_unlinked;
 494
 495         set_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 496
 497         gfs2_glock_dq_uninit(&t_gh);
 498
 499         return 0;
 500
 501  fail_unlinked:
 502         gfs2_unlinked_cleanup(sdp);
 503
 504  fail:
 505         t_gh.gh_flags |= GL_NOCACHE;
 506         gfs2_glock_dq_uninit(&t_gh);
 507
 508         return error;
 509 }
 510
 511 /**
 512  * gfs2_make_fs_ro - Turn a Read-Write FS into a Read-Only one
 513  * @sdp: the filesystem
 514  *
 515  * Returns: errno
 516  */
 517
 518 int gfs2_make_fs_ro(struct gfs2_sbd *sdp)
 519 {
 520         struct gfs2_holder t_gh;
 521         int error;
 522
 523         gfs2_unlinked_dealloc(sdp);
 524         gfs2_quota_sync(sdp);
 525         gfs2_statfs_sync(sdp);
 526
 527         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
 528                                 GL_LOCAL_EXCL | GL_NOCACHE,
 529                                 &t_gh);
 530         if (error && !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
 531                 return error;
 532
 533         gfs2_meta_syncfs(sdp);
 534         gfs2_log_shutdown(sdp);
 535
 536         clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 537
 538         if (t_gh.gh_gl)
 539                 gfs2_glock_dq_uninit(&t_gh);
 540
 541         gfs2_unlinked_cleanup(sdp);
 542         gfs2_quota_cleanup(sdp);
 543
 544         return error;
 545 }
 546
 547 int gfs2_statfs_init(struct gfs2_sbd *sdp)
 548 {
 549         struct gfs2_inode *m_ip = sdp->sd_statfs_inode->u.generic_ip;
 550         struct gfs2_statfs_change *m_sc = &sdp->sd_statfs_master;
 551         struct gfs2_inode *l_ip = sdp->sd_sc_inode->u.generic_ip;
 552         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 553         struct buffer_head *m_bh, *l_bh;
 554         struct gfs2_holder gh;
 555         int error;
 556
 557         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 558                                    &gh);
 559         if (error)
 560                 return error;
 561
 562         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 563         if (error)
 564                 goto out;
 565
 566         if (sdp->sd_args.ar_spectator) {
 567                 spin_lock(&sdp->sd_statfs_spin);
 568                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 569                                       sizeof(struct gfs2_dinode));
 570                 spin_unlock(&sdp->sd_statfs_spin);
 571         } else {
 572                 error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 573                 if (error)
 574                         goto out_m_bh;
 575
 576                 spin_lock(&sdp->sd_statfs_spin);
 577                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 578                                       sizeof(struct gfs2_dinode));
 579                 gfs2_statfs_change_in(l_sc, l_bh->b_data +
 580                                       sizeof(struct gfs2_dinode));
 581                 spin_unlock(&sdp->sd_statfs_spin);
 582
 583                 brelse(l_bh);
 584         }
 585
 586  out_m_bh:
 587         brelse(m_bh);
 588
 589  out:
 590         gfs2_glock_dq_uninit(&gh);
 591
 592         return 0;
 593 }
 594
 595 void gfs2_statfs_change(struct gfs2_sbd *sdp, int64_t total, int64_t free,
 596                         int64_t dinodes)
 597 {
 598         struct gfs2_inode *l_ip = sdp->sd_sc_inode->u.generic_ip;
 599         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 600         struct buffer_head *l_bh;
 601         int error;
 602
 603         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 604         if (error)
 605                 return;
 606
 607         mutex_lock(&sdp->sd_statfs_mutex);
 608         gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
 609         mutex_unlock(&sdp->sd_statfs_mutex);
 610
 611         spin_lock(&sdp->sd_statfs_spin);
 612         l_sc->sc_total += total;
 613         l_sc->sc_free += free;
 614         l_sc->sc_dinodes += dinodes;
 615         gfs2_statfs_change_out(l_sc, l_bh->b_data +
 616                                sizeof(struct gfs2_dinode));
 617         spin_unlock(&sdp->sd_statfs_spin);
 618
 619         brelse(l_bh);
 620 }
 621
 622 int gfs2_statfs_sync(struct gfs2_sbd *sdp)
 623 {
 624         struct gfs2_inode *m_ip = sdp->sd_statfs_inode->u.generic_ip;
 625         struct gfs2_inode *l_ip = sdp->sd_sc_inode->u.generic_ip;
 626         struct gfs2_statfs_change *m_sc = &sdp->sd_statfs_master;
 627         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 628         struct gfs2_holder gh;
 629         struct buffer_head *m_bh, *l_bh;
 630         int error;
 631
 632         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 633                                    &gh);
 634         if (error)
 635                 return error;
 636
 637         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 638         if (error)
 639                 goto out;
 640
 641         spin_lock(&sdp->sd_statfs_spin);
 642         gfs2_statfs_change_in(m_sc, m_bh->b_data +
 643                               sizeof(struct gfs2_dinode));
 644         if (!l_sc->sc_total && !l_sc->sc_free && !l_sc->sc_dinodes) {
 645                 spin_unlock(&sdp->sd_statfs_spin);
 646                 goto out_bh;
 647         }
 648         spin_unlock(&sdp->sd_statfs_spin);
 649
 650         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 651         if (error)
 652                 goto out_bh;
 653
 654         error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
 655         if (error)
 656                 goto out_bh2;
 657
 658         mutex_lock(&sdp->sd_statfs_mutex);
 659         gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
 660         mutex_unlock(&sdp->sd_statfs_mutex);
 661
 662         spin_lock(&sdp->sd_statfs_spin);
 663         m_sc->sc_total += l_sc->sc_total;
 664         m_sc->sc_free += l_sc->sc_free;
 665         m_sc->sc_dinodes += l_sc->sc_dinodes;
 666         memset(l_sc, 0, sizeof(struct gfs2_statfs_change));
 667         memset(l_bh->b_data + sizeof(struct gfs2_dinode),
 668                0, sizeof(struct gfs2_statfs_change));
 669         spin_unlock(&sdp->sd_statfs_spin);
 670
 671         gfs2_trans_add_bh(m_ip->i_gl, m_bh, 1);
 672         gfs2_statfs_change_out(m_sc, m_bh->b_data + sizeof(struct gfs2_dinode));
 673
 674         gfs2_trans_end(sdp);
 675
 676  out_bh2:
 677         brelse(l_bh);
 678
 679  out_bh:
 680         brelse(m_bh);
 681
 682  out:
 683         gfs2_glock_dq_uninit(&gh);
 684
 685         return error;
 686 }
 687
 688 /**
 689  * gfs2_statfs_i - Do a statfs
 690  * @sdp: the filesystem
 691  * @sg: the sg structure
 692  *
 693  * Returns: errno
 694  */
 695
 696 int gfs2_statfs_i(struct gfs2_sbd *sdp, struct gfs2_statfs_change *sc)
 697 {
 698         struct gfs2_statfs_change *m_sc = &sdp->sd_statfs_master;
 699         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 700
 701         spin_lock(&sdp->sd_statfs_spin);
 702
 703         *sc = *m_sc;
 704         sc->sc_total += l_sc->sc_total;
 705         sc->sc_free += l_sc->sc_free;
 706         sc->sc_dinodes += l_sc->sc_dinodes;
 707
 708         spin_unlock(&sdp->sd_statfs_spin);
 709
 710         if (sc->sc_free < 0)
 711                 sc->sc_free = 0;
 712         if (sc->sc_free > sc->sc_total)
 713                 sc->sc_free = sc->sc_total;
 714         if (sc->sc_dinodes < 0)
 715                 sc->sc_dinodes = 0;
 716
 717         return 0;
 718 }
 719
 720 /**
 721  * statfs_fill - fill in the sg for a given RG
 722  * @rgd: the RG
 723  * @sc: the sc structure
 724  *
 725  * Returns: 0 on success, -ESTALE if the LVB is invalid
 726  */
 727
 728 static int statfs_slow_fill(struct gfs2_rgrpd *rgd,
 729                             struct gfs2_statfs_change *sc)
 730 {
 731         gfs2_rgrp_verify(rgd);
 732         sc->sc_total += rgd->rd_ri.ri_data;
 733         sc->sc_free += rgd->rd_rg.rg_free;
 734         sc->sc_dinodes += rgd->rd_rg.rg_dinodes;
 735         return 0;
 736 }
 737
 738 /**
 739  * gfs2_statfs_slow - Stat a filesystem using asynchronous locking
 740  * @sdp: the filesystem
 741  * @sc: the sc info that will be returned
 742  *
 743  * Any error (other than a signal) will cause this routine to fall back
 744  * to the synchronous version.
 745  *
 746  * FIXME: This really shouldn't busy wait like this.
 747  *
 748  * Returns: errno
 749  */
 750
 751 int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change *sc)
 752 {
 753         struct gfs2_holder ri_gh;
 754         struct gfs2_rgrpd *rgd_next;
 755         struct gfs2_holder *gha, *gh;
 756         unsigned int slots = 64;
 757         unsigned int x;
 758         int done;
 759         int error = 0, err;
 760
 761         memset(sc, 0, sizeof(struct gfs2_statfs_change));
 762         gha = kcalloc(slots, sizeof(struct gfs2_holder), GFP_KERNEL);
 763         if (!gha)
 764                 return -ENOMEM;
 765
 766         error = gfs2_rindex_hold(sdp, &ri_gh);
 767         if (error)
 768                 goto out;
 769
 770         rgd_next = gfs2_rgrpd_get_first(sdp);
 771
 772         for (;;) {
 773                 done = 1;
 774
 775                 for (x = 0; x < slots; x++) {
 776                         gh = gha + x;
 777
 778                         if (gh->gh_gl && gfs2_glock_poll(gh)) {
 779                                 err = gfs2_glock_wait(gh);
 780                                 if (err) {
 781                                         gfs2_holder_uninit(gh);
 782                                         error = err;
 783                                 } else {
 784                                         if (!error)
 785                                                 error = statfs_slow_fill(
 786                                                         gh->gh_gl->gl_object, sc);
 787                                         gfs2_glock_dq_uninit(gh);
 788                                 }
 789                         }
 790
 791                         if (gh->gh_gl)
 792                                 done = 0;
 793                         else if (rgd_next && !error) {
 794                                 error = gfs2_glock_nq_init(rgd_next->rd_gl,
 795                                                            LM_ST_SHARED,
 796                                                            GL_ASYNC,
 797                                                            gh);
 798                                 rgd_next = gfs2_rgrpd_get_next(rgd_next);
 799                                 done = 0;
 800                         }
 801
 802                         if (signal_pending(current))
 803                                 error = -ERESTARTSYS;
 804                 }
 805
 806                 if (done)
 807                         break;
 808
 809                 yield();
 810         }
 811
 812         gfs2_glock_dq_uninit(&ri_gh);
 813
 814  out:
 815         kfree(gha);
 816
 817         return error;
 818 }
 819
 820 struct lfcc {
 821         struct list_head list;
 822         struct gfs2_holder gh;
 823 };
 824
 825 /**
 826  * gfs2_lock_fs_check_clean - Stop all writes to the FS and check that all
 827  *                            journals are clean
 828  * @sdp: the file system
 829  * @state: the state to put the transaction lock into
 830  * @t_gh: the hold on the transaction lock
 831  *
 832  * Returns: errno
 833  */
 834
 835 static int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp,
 836                                     struct gfs2_holder *t_gh)
 837 {
 838         struct gfs2_inode *ip;
 839         struct gfs2_holder ji_gh;
 840         struct gfs2_jdesc *jd;
 841         struct lfcc *lfcc;
 842         LIST_HEAD(list);
 843         struct gfs2_log_header lh;
 844         int error;
 845
 846         error = gfs2_jindex_hold(sdp, &ji_gh);
 847         if (error)
 848                 return error;
 849
 850         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 851                 lfcc = kmalloc(sizeof(struct lfcc), GFP_KERNEL);
 852                 if (!lfcc) {
 853                         error = -ENOMEM;
 854                         goto out;
 855                 }
 856                 ip = jd->jd_inode->u.generic_ip;
 857                 error = gfs2_glock_nq_init(ip->i_gl,
 858                                            LM_ST_SHARED, 0,
 859                                            &lfcc->gh);
 860                 if (error) {
 861                         kfree(lfcc);
 862                         goto out;
 863                 }
 864                 list_add(&lfcc->list, &list);
 865         }
 866
 867         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_DEFERRED,
 868                                LM_FLAG_PRIORITY | GL_NOCACHE,
 869                                t_gh);
 870
 871         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 872                 error = gfs2_jdesc_check(jd);
 873                 if (error)
 874                         break;
 875                 error = gfs2_find_jhead(jd, &lh);
 876                 if (error)
 877                         break;
 878                 if (!(lh.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 879                         error = -EBUSY;
 880                         break;
 881                 }
 882         }
 883
 884         if (error)
 885                 gfs2_glock_dq_uninit(t_gh);
 886
 887  out:
 888         while (!list_empty(&list)) {
 889                 lfcc = list_entry(list.next, struct lfcc, list);
 890                 list_del(&lfcc->list);
 891                 gfs2_glock_dq_uninit(&lfcc->gh);
 892                 kfree(lfcc);
 893         }
 894         gfs2_glock_dq_uninit(&ji_gh);
 895
 896         return error;
 897 }
 898
 899 /**
 900  * gfs2_freeze_fs - freezes the file system
 901  * @sdp: the file system
 902  *
 903  * This function flushes data and meta data for all machines by
 904  * aquiring the transaction log exclusively.  All journals are
 905  * ensured to be in a clean state as well.
 906  *
 907  * Returns: errno
 908  */
 909
 910 int gfs2_freeze_fs(struct gfs2_sbd *sdp)
 911 {
 912         int error = 0;
 913
 914         mutex_lock(&sdp->sd_freeze_lock);
 915
 916         if (!sdp->sd_freeze_count++) {
 917                 error = gfs2_lock_fs_check_clean(sdp, &sdp->sd_freeze_gh);
 918                 if (error)
 919                         sdp->sd_freeze_count--;
 920         }
 921
 922         mutex_unlock(&sdp->sd_freeze_lock);
 923
 924         return error;
 925 }
 926
 927 /**
 928  * gfs2_unfreeze_fs - unfreezes the file system
 929  * @sdp: the file system
 930  *
 931  * This function allows the file system to proceed by unlocking
 932  * the exclusively held transaction lock.  Other GFS2 nodes are
 933  * now free to acquire the lock shared and go on with their lives.
 934  *
 935  */
 936
 937 void gfs2_unfreeze_fs(struct gfs2_sbd *sdp)
 938 {
 939         mutex_lock(&sdp->sd_freeze_lock);
 940
 941         if (sdp->sd_freeze_count && !--sdp->sd_freeze_count)
 942                 gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
 943
 944         mutex_unlock(&sdp->sd_freeze_lock);
 945 }
 946