SAFE public projects git trees. - safe/jmp/linux-2.6/blob - fs/gfs2/super.c

   1 /*
   2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3  * Copyright (C) 2004-2006 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
  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 /**
 267  * gfs2_jindex_hold - Grab a lock on the jindex
 268  * @sdp: The GFS2 superblock
 269  * @ji_gh: the holder for the jindex glock
 270  *
 271  * This is very similar to the gfs2_rindex_hold() function, except that
 272  * in general we hold the jindex lock for longer periods of time and
 273  * we grab it far less frequently (in general) then the rgrp lock.
 274  *
 275  * Returns: errno
 276  */
 277
 278 int gfs2_jindex_hold(struct gfs2_sbd *sdp, struct gfs2_holder *ji_gh)
 279 {
 280         struct gfs2_inode *dip = sdp->sd_jindex->u.generic_ip;
 281         struct qstr name;
 282         char buf[20];
 283         struct gfs2_jdesc *jd;
 284         int error;
 285
 286         name.name = buf;
 287
 288         mutex_lock(&sdp->sd_jindex_mutex);
 289
 290         for (;;) {
 291                 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED,
 292                                            GL_LOCAL_EXCL, ji_gh);
 293                 if (error)
 294                         break;
 295
 296                 name.len = sprintf(buf, "journal%u", sdp->sd_journals);
 297                 name.hash = gfs2_disk_hash(name.name, name.len);
 298
 299                 error = gfs2_dir_search(sdp->sd_jindex,
 300                                         &name, NULL, NULL);
 301                 if (error == -ENOENT) {
 302                         error = 0;
 303                         break;
 304                 }
 305
 306                 gfs2_glock_dq_uninit(ji_gh);
 307
 308                 if (error)
 309                         break;
 310
 311                 error = -ENOMEM;
 312                 jd = kzalloc(sizeof(struct gfs2_jdesc), GFP_KERNEL);
 313                 if (!jd)
 314                         break;
 315
 316                 jd->jd_inode = gfs2_lookupi(sdp->sd_jindex, &name, 1, NULL);
 317                 if (!jd->jd_inode || IS_ERR(jd->jd_inode)) {
 318                         if (!jd->jd_inode)
 319                                 error = -ENOENT;
 320                         else
 321                                 error = PTR_ERR(jd->jd_inode);
 322                         kfree(jd);
 323                         break;
 324                 }
 325
 326                 spin_lock(&sdp->sd_jindex_spin);
 327                 jd->jd_jid = sdp->sd_journals++;
 328                 list_add_tail(&jd->jd_list, &sdp->sd_jindex_list);
 329                 spin_unlock(&sdp->sd_jindex_spin);
 330         }
 331
 332         mutex_unlock(&sdp->sd_jindex_mutex);
 333
 334         return error;
 335 }
 336
 337 /**
 338  * gfs2_jindex_free - Clear all the journal index information
 339  * @sdp: The GFS2 superblock
 340  *
 341  */
 342
 343 void gfs2_jindex_free(struct gfs2_sbd *sdp)
 344 {
 345         struct list_head list;
 346         struct gfs2_jdesc *jd;
 347
 348         spin_lock(&sdp->sd_jindex_spin);
 349         list_add(&list, &sdp->sd_jindex_list);
 350         list_del_init(&sdp->sd_jindex_list);
 351         sdp->sd_journals = 0;
 352         spin_unlock(&sdp->sd_jindex_spin);
 353
 354         while (!list_empty(&list)) {
 355                 jd = list_entry(list.next, struct gfs2_jdesc, jd_list);
 356                 list_del(&jd->jd_list);
 357                 iput(jd->jd_inode);
 358                 kfree(jd);
 359         }
 360 }
 361
 362 static struct gfs2_jdesc *jdesc_find_i(struct list_head *head, unsigned int jid)
 363 {
 364         struct gfs2_jdesc *jd;
 365         int found = 0;
 366
 367         list_for_each_entry(jd, head, jd_list) {
 368                 if (jd->jd_jid == jid) {
 369                         found = 1;
 370                         break;
 371                 }
 372         }
 373
 374         if (!found)
 375                 jd = NULL;
 376
 377         return jd;
 378 }
 379
 380 struct gfs2_jdesc *gfs2_jdesc_find(struct gfs2_sbd *sdp, unsigned int jid)
 381 {
 382         struct gfs2_jdesc *jd;
 383
 384         spin_lock(&sdp->sd_jindex_spin);
 385         jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
 386         spin_unlock(&sdp->sd_jindex_spin);
 387
 388         return jd;
 389 }
 390
 391 void gfs2_jdesc_make_dirty(struct gfs2_sbd *sdp, unsigned int jid)
 392 {
 393         struct gfs2_jdesc *jd;
 394
 395         spin_lock(&sdp->sd_jindex_spin);
 396         jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
 397         if (jd)
 398                 jd->jd_dirty = 1;
 399         spin_unlock(&sdp->sd_jindex_spin);
 400 }
 401
 402 struct gfs2_jdesc *gfs2_jdesc_find_dirty(struct gfs2_sbd *sdp)
 403 {
 404         struct gfs2_jdesc *jd;
 405         int found = 0;
 406
 407         spin_lock(&sdp->sd_jindex_spin);
 408
 409         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 410                 if (jd->jd_dirty) {
 411                         jd->jd_dirty = 0;
 412                         found = 1;
 413                         break;
 414                 }
 415         }
 416         spin_unlock(&sdp->sd_jindex_spin);
 417
 418         if (!found)
 419                 jd = NULL;
 420
 421         return jd;
 422 }
 423
 424 int gfs2_jdesc_check(struct gfs2_jdesc *jd)
 425 {
 426         struct gfs2_inode *ip = jd->jd_inode->u.generic_ip;
 427         struct gfs2_sbd *sdp = ip->i_sbd;
 428         int ar;
 429         int error;
 430
 431         if (ip->i_di.di_size < (8 << 20) ||
 432             ip->i_di.di_size > (1 << 30) ||
 433             (ip->i_di.di_size & (sdp->sd_sb.sb_bsize - 1))) {
 434                 gfs2_consist_inode(ip);
 435                 return -EIO;
 436         }
 437         jd->jd_blocks = ip->i_di.di_size >> sdp->sd_sb.sb_bsize_shift;
 438
 439         error = gfs2_write_alloc_required(ip,
 440                                           0, ip->i_di.di_size,
 441                                           &ar);
 442         if (!error && ar) {
 443                 gfs2_consist_inode(ip);
 444                 error = -EIO;
 445         }
 446
 447         return error;
 448 }
 449
 450 /**
 451  * gfs2_make_fs_rw - Turn a Read-Only FS into a Read-Write one
 452  * @sdp: the filesystem
 453  *
 454  * Returns: errno
 455  */
 456
 457 int gfs2_make_fs_rw(struct gfs2_sbd *sdp)
 458 {
 459         struct gfs2_inode *ip = sdp->sd_jdesc->jd_inode->u.generic_ip;
 460         struct gfs2_glock *j_gl = ip->i_gl;
 461         struct gfs2_holder t_gh;
 462         struct gfs2_log_header head;
 463         int error;
 464
 465         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
 466                                    GL_LOCAL_EXCL, &t_gh);
 467         if (error)
 468                 return error;
 469
 470         gfs2_meta_cache_flush(ip);
 471         j_gl->gl_ops->go_inval(j_gl, DIO_METADATA | DIO_DATA);
 472
 473         error = gfs2_find_jhead(sdp->sd_jdesc, &head);
 474         if (error)
 475                 goto fail;
 476
 477         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 478                 gfs2_consist(sdp);
 479                 error = -EIO;
 480                 goto fail;
 481         }
 482
 483         /*  Initialize some head of the log stuff  */
 484         sdp->sd_log_sequence = head.lh_sequence + 1;
 485         gfs2_log_pointers_init(sdp, head.lh_blkno);
 486
 487         error = gfs2_unlinked_init(sdp);
 488         if (error)
 489                 goto fail;
 490         error = gfs2_quota_init(sdp);
 491         if (error)
 492                 goto fail_unlinked;
 493
 494         set_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 495
 496         gfs2_glock_dq_uninit(&t_gh);
 497
 498         return 0;
 499
 500  fail_unlinked:
 501         gfs2_unlinked_cleanup(sdp);
 502
 503  fail:
 504         t_gh.gh_flags |= GL_NOCACHE;
 505         gfs2_glock_dq_uninit(&t_gh);
 506
 507         return error;
 508 }
 509
 510 /**
 511  * gfs2_make_fs_ro - Turn a Read-Write FS into a Read-Only one
 512  * @sdp: the filesystem
 513  *
 514  * Returns: errno
 515  */
 516
 517 int gfs2_make_fs_ro(struct gfs2_sbd *sdp)
 518 {
 519         struct gfs2_holder t_gh;
 520         int error;
 521
 522         gfs2_unlinked_dealloc(sdp);
 523         gfs2_quota_sync(sdp);
 524         gfs2_statfs_sync(sdp);
 525
 526         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
 527                                 GL_LOCAL_EXCL | GL_NOCACHE,
 528                                 &t_gh);
 529         if (error && !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
 530                 return error;
 531
 532         gfs2_meta_syncfs(sdp);
 533         gfs2_log_shutdown(sdp);
 534
 535         clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 536
 537         if (t_gh.gh_gl)
 538                 gfs2_glock_dq_uninit(&t_gh);
 539
 540         gfs2_unlinked_cleanup(sdp);
 541         gfs2_quota_cleanup(sdp);
 542
 543         return error;
 544 }
 545
 546 int gfs2_statfs_init(struct gfs2_sbd *sdp)
 547 {
 548         struct gfs2_inode *m_ip = sdp->sd_statfs_inode->u.generic_ip;
 549         struct gfs2_statfs_change *m_sc = &sdp->sd_statfs_master;
 550         struct gfs2_inode *l_ip = sdp->sd_sc_inode->u.generic_ip;
 551         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 552         struct buffer_head *m_bh, *l_bh;
 553         struct gfs2_holder gh;
 554         int error;
 555
 556         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 557                                    &gh);
 558         if (error)
 559                 return error;
 560
 561         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 562         if (error)
 563                 goto out;
 564
 565         if (sdp->sd_args.ar_spectator) {
 566                 spin_lock(&sdp->sd_statfs_spin);
 567                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 568                                       sizeof(struct gfs2_dinode));
 569                 spin_unlock(&sdp->sd_statfs_spin);
 570         } else {
 571                 error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 572                 if (error)
 573                         goto out_m_bh;
 574
 575                 spin_lock(&sdp->sd_statfs_spin);
 576                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 577                                       sizeof(struct gfs2_dinode));
 578                 gfs2_statfs_change_in(l_sc, l_bh->b_data +
 579                                       sizeof(struct gfs2_dinode));
 580                 spin_unlock(&sdp->sd_statfs_spin);
 581
 582                 brelse(l_bh);
 583         }
 584
 585  out_m_bh:
 586         brelse(m_bh);
 587
 588  out:
 589         gfs2_glock_dq_uninit(&gh);
 590
 591         return 0;
 592 }
 593
 594 void gfs2_statfs_change(struct gfs2_sbd *sdp, int64_t total, int64_t free,
 595                         int64_t dinodes)
 596 {
 597         struct gfs2_inode *l_ip = sdp->sd_sc_inode->u.generic_ip;
 598         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 599         struct buffer_head *l_bh;
 600         int error;
 601
 602         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 603         if (error)
 604                 return;
 605
 606         mutex_lock(&sdp->sd_statfs_mutex);
 607         gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
 608         mutex_unlock(&sdp->sd_statfs_mutex);
 609
 610         spin_lock(&sdp->sd_statfs_spin);
 611         l_sc->sc_total += total;
 612         l_sc->sc_free += free;
 613         l_sc->sc_dinodes += dinodes;
 614         gfs2_statfs_change_out(l_sc, l_bh->b_data +
 615                                sizeof(struct gfs2_dinode));
 616         spin_unlock(&sdp->sd_statfs_spin);
 617
 618         brelse(l_bh);
 619 }
 620
 621 int gfs2_statfs_sync(struct gfs2_sbd *sdp)
 622 {
 623         struct gfs2_inode *m_ip = sdp->sd_statfs_inode->u.generic_ip;
 624         struct gfs2_inode *l_ip = sdp->sd_sc_inode->u.generic_ip;
 625         struct gfs2_statfs_change *m_sc = &sdp->sd_statfs_master;
 626         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 627         struct gfs2_holder gh;
 628         struct buffer_head *m_bh, *l_bh;
 629         int error;
 630
 631         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 632                                    &gh);
 633         if (error)
 634                 return error;
 635
 636         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 637         if (error)
 638                 goto out;
 639
 640         spin_lock(&sdp->sd_statfs_spin);
 641         gfs2_statfs_change_in(m_sc, m_bh->b_data +
 642                               sizeof(struct gfs2_dinode));
 643         if (!l_sc->sc_total && !l_sc->sc_free && !l_sc->sc_dinodes) {
 644                 spin_unlock(&sdp->sd_statfs_spin);
 645                 goto out_bh;
 646         }
 647         spin_unlock(&sdp->sd_statfs_spin);
 648
 649         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 650         if (error)
 651                 goto out_bh;
 652
 653         error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
 654         if (error)
 655                 goto out_bh2;
 656
 657         mutex_lock(&sdp->sd_statfs_mutex);
 658         gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
 659         mutex_unlock(&sdp->sd_statfs_mutex);
 660
 661         spin_lock(&sdp->sd_statfs_spin);
 662         m_sc->sc_total += l_sc->sc_total;
 663         m_sc->sc_free += l_sc->sc_free;
 664         m_sc->sc_dinodes += l_sc->sc_dinodes;
 665         memset(l_sc, 0, sizeof(struct gfs2_statfs_change));
 666         memset(l_bh->b_data + sizeof(struct gfs2_dinode),
 667                0, sizeof(struct gfs2_statfs_change));
 668         spin_unlock(&sdp->sd_statfs_spin);
 669
 670         gfs2_trans_add_bh(m_ip->i_gl, m_bh, 1);
 671         gfs2_statfs_change_out(m_sc, m_bh->b_data + sizeof(struct gfs2_dinode));
 672
 673         gfs2_trans_end(sdp);
 674
 675  out_bh2:
 676         brelse(l_bh);
 677
 678  out_bh:
 679         brelse(m_bh);
 680
 681  out:
 682         gfs2_glock_dq_uninit(&gh);
 683
 684         return error;
 685 }
 686
 687 /**
 688  * gfs2_statfs_i - Do a statfs
 689  * @sdp: the filesystem
 690  * @sg: the sg structure
 691  *
 692  * Returns: errno
 693  */
 694
 695 int gfs2_statfs_i(struct gfs2_sbd *sdp, struct gfs2_statfs_change *sc)
 696 {
 697         struct gfs2_statfs_change *m_sc = &sdp->sd_statfs_master;
 698         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 699
 700         spin_lock(&sdp->sd_statfs_spin);
 701
 702         *sc = *m_sc;
 703         sc->sc_total += l_sc->sc_total;
 704         sc->sc_free += l_sc->sc_free;
 705         sc->sc_dinodes += l_sc->sc_dinodes;
 706
 707         spin_unlock(&sdp->sd_statfs_spin);
 708
 709         if (sc->sc_free < 0)
 710                 sc->sc_free = 0;
 711         if (sc->sc_free > sc->sc_total)
 712                 sc->sc_free = sc->sc_total;
 713         if (sc->sc_dinodes < 0)
 714                 sc->sc_dinodes = 0;
 715
 716         return 0;
 717 }
 718
 719 /**
 720  * statfs_fill - fill in the sg for a given RG
 721  * @rgd: the RG
 722  * @sc: the sc structure
 723  *
 724  * Returns: 0 on success, -ESTALE if the LVB is invalid
 725  */
 726
 727 static int statfs_slow_fill(struct gfs2_rgrpd *rgd,
 728                             struct gfs2_statfs_change *sc)
 729 {
 730         gfs2_rgrp_verify(rgd);
 731         sc->sc_total += rgd->rd_ri.ri_data;
 732         sc->sc_free += rgd->rd_rg.rg_free;
 733         sc->sc_dinodes += rgd->rd_rg.rg_dinodes;
 734         return 0;
 735 }
 736
 737 /**
 738  * gfs2_statfs_slow - Stat a filesystem using asynchronous locking
 739  * @sdp: the filesystem
 740  * @sc: the sc info that will be returned
 741  *
 742  * Any error (other than a signal) will cause this routine to fall back
 743  * to the synchronous version.
 744  *
 745  * FIXME: This really shouldn't busy wait like this.
 746  *
 747  * Returns: errno
 748  */
 749
 750 int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change *sc)
 751 {
 752         struct gfs2_holder ri_gh;
 753         struct gfs2_rgrpd *rgd_next;
 754         struct gfs2_holder *gha, *gh;
 755         unsigned int slots = 64;
 756         unsigned int x;
 757         int done;
 758         int error = 0, err;
 759
 760         memset(sc, 0, sizeof(struct gfs2_statfs_change));
 761         gha = kcalloc(slots, sizeof(struct gfs2_holder), GFP_KERNEL);
 762         if (!gha)
 763                 return -ENOMEM;
 764
 765         error = gfs2_rindex_hold(sdp, &ri_gh);
 766         if (error)
 767                 goto out;
 768
 769         rgd_next = gfs2_rgrpd_get_first(sdp);
 770
 771         for (;;) {
 772                 done = 1;
 773
 774                 for (x = 0; x < slots; x++) {
 775                         gh = gha + x;
 776
 777                         if (gh->gh_gl && gfs2_glock_poll(gh)) {
 778                                 err = gfs2_glock_wait(gh);
 779                                 if (err) {
 780                                         gfs2_holder_uninit(gh);
 781                                         error = err;
 782                                 } else {
 783                                         if (!error)
 784                                                 error = statfs_slow_fill(
 785                                                         gh->gh_gl->gl_object, sc);
 786                                         gfs2_glock_dq_uninit(gh);
 787                                 }
 788                         }
 789
 790                         if (gh->gh_gl)
 791                                 done = 0;
 792                         else if (rgd_next && !error) {
 793                                 error = gfs2_glock_nq_init(rgd_next->rd_gl,
 794                                                            LM_ST_SHARED,
 795                                                            GL_ASYNC,
 796                                                            gh);
 797                                 rgd_next = gfs2_rgrpd_get_next(rgd_next);
 798                                 done = 0;
 799                         }
 800
 801                         if (signal_pending(current))
 802                                 error = -ERESTARTSYS;
 803                 }
 804
 805                 if (done)
 806                         break;
 807
 808                 yield();
 809         }
 810
 811         gfs2_glock_dq_uninit(&ri_gh);
 812
 813  out:
 814         kfree(gha);
 815
 816         return error;
 817 }
 818
 819 struct lfcc {
 820         struct list_head list;
 821         struct gfs2_holder gh;
 822 };
 823
 824 /**
 825  * gfs2_lock_fs_check_clean - Stop all writes to the FS and check that all
 826  *                            journals are clean
 827  * @sdp: the file system
 828  * @state: the state to put the transaction lock into
 829  * @t_gh: the hold on the transaction lock
 830  *
 831  * Returns: errno
 832  */
 833
 834 static int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp,
 835                                     struct gfs2_holder *t_gh)
 836 {
 837         struct gfs2_inode *ip;
 838         struct gfs2_holder ji_gh;
 839         struct gfs2_jdesc *jd;
 840         struct lfcc *lfcc;
 841         LIST_HEAD(list);
 842         struct gfs2_log_header lh;
 843         int error;
 844
 845         error = gfs2_jindex_hold(sdp, &ji_gh);
 846         if (error)
 847                 return error;
 848
 849         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 850                 lfcc = kmalloc(sizeof(struct lfcc), GFP_KERNEL);
 851                 if (!lfcc) {
 852                         error = -ENOMEM;
 853                         goto out;
 854                 }
 855                 ip = jd->jd_inode->u.generic_ip;
 856                 error = gfs2_glock_nq_init(ip->i_gl,
 857                                            LM_ST_SHARED, 0,
 858                                            &lfcc->gh);
 859                 if (error) {
 860                         kfree(lfcc);
 861                         goto out;
 862                 }
 863                 list_add(&lfcc->list, &list);
 864         }
 865
 866         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_DEFERRED,
 867                                LM_FLAG_PRIORITY | GL_NOCACHE,
 868                                t_gh);
 869
 870         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 871                 error = gfs2_jdesc_check(jd);
 872                 if (error)
 873                         break;
 874                 error = gfs2_find_jhead(jd, &lh);
 875                 if (error)
 876                         break;
 877                 if (!(lh.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 878                         error = -EBUSY;
 879                         break;
 880                 }
 881         }
 882
 883         if (error)
 884                 gfs2_glock_dq_uninit(t_gh);
 885
 886  out:
 887         while (!list_empty(&list)) {
 888                 lfcc = list_entry(list.next, struct lfcc, list);
 889                 list_del(&lfcc->list);
 890                 gfs2_glock_dq_uninit(&lfcc->gh);
 891                 kfree(lfcc);
 892         }
 893         gfs2_glock_dq_uninit(&ji_gh);
 894
 895         return error;
 896 }
 897
 898 /**
 899  * gfs2_freeze_fs - freezes the file system
 900  * @sdp: the file system
 901  *
 902  * This function flushes data and meta data for all machines by
 903  * aquiring the transaction log exclusively.  All journals are
 904  * ensured to be in a clean state as well.
 905  *
 906  * Returns: errno
 907  */
 908
 909 int gfs2_freeze_fs(struct gfs2_sbd *sdp)
 910 {
 911         int error = 0;
 912
 913         mutex_lock(&sdp->sd_freeze_lock);
 914
 915         if (!sdp->sd_freeze_count++) {
 916                 error = gfs2_lock_fs_check_clean(sdp, &sdp->sd_freeze_gh);
 917                 if (error)
 918                         sdp->sd_freeze_count--;
 919         }
 920
 921         mutex_unlock(&sdp->sd_freeze_lock);
 922
 923         return error;
 924 }
 925
 926 /**
 927  * gfs2_unfreeze_fs - unfreezes the file system
 928  * @sdp: the file system
 929  *
 930  * This function allows the file system to proceed by unlocking
 931  * the exclusively held transaction lock.  Other GFS2 nodes are
 932  * now free to acquire the lock shared and go on with their lives.
 933  *
 934  */
 935
 936 void gfs2_unfreeze_fs(struct gfs2_sbd *sdp)
 937 {
 938         mutex_lock(&sdp->sd_freeze_lock);
 939
 940         if (sdp->sd_freeze_count && !--sdp->sd_freeze_count)
 941                 gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
 942
 943         mutex_unlock(&sdp->sd_freeze_lock);
 944 }
 945