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