err.no Git - linux-2.6/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
 303                 error = gfs2_dir_search(sdp->sd_jindex->u.generic_ip,
 304                                         &name, NULL, NULL);
 305                 if (error == -ENOENT) {
 306                         error = 0;
 307                         break;
 308                 }
 309
 310                 gfs2_glock_dq_uninit(ji_gh);
 311
 312                 if (error)
 313                         break;
 314
 315                 error = -ENOMEM;
 316                 jd = kzalloc(sizeof(struct gfs2_jdesc), GFP_KERNEL);
 317                 if (!jd)
 318                         break;
 319
 320                 error = gfs2_lookupi(sdp->sd_jindex, &name, 1, &jd->jd_inode);
 321                 if (error) {
 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 int gfs2_lookup_master_dir(struct gfs2_sbd *sdp)
 451 {
 452         struct inode *inode = NULL;
 453         struct gfs2_glock *gl;
 454         int error;
 455
 456         error = gfs2_glock_get(sdp,
 457                                sdp->sd_sb.sb_master_dir.no_addr,
 458                                &gfs2_inode_glops, CREATE, &gl);
 459         if (!error) {
 460                 error = gfs2_lookup_simple(sdp->sd_root_dir, ".gfs2_admin",
 461                                            &inode);
 462                 sdp->sd_master_dir = inode;
 463                 gfs2_glock_put(gl);
 464         }
 465
 466         return error;
 467 }
 468
 469 /**
 470  * gfs2_make_fs_rw - Turn a Read-Only FS into a Read-Write one
 471  * @sdp: the filesystem
 472  *
 473  * Returns: errno
 474  */
 475
 476 int gfs2_make_fs_rw(struct gfs2_sbd *sdp)
 477 {
 478         struct gfs2_inode *ip = sdp->sd_jdesc->jd_inode->u.generic_ip;
 479         struct gfs2_glock *j_gl = ip->i_gl;
 480         struct gfs2_holder t_gh;
 481         struct gfs2_log_header head;
 482         int error;
 483
 484         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
 485                                    GL_LOCAL_EXCL | GL_NEVER_RECURSE, &t_gh);
 486         if (error)
 487                 return error;
 488
 489         gfs2_meta_cache_flush(ip);
 490         j_gl->gl_ops->go_inval(j_gl, DIO_METADATA | DIO_DATA);
 491
 492         error = gfs2_find_jhead(sdp->sd_jdesc, &head);
 493         if (error)
 494                 goto fail;
 495
 496         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 497                 gfs2_consist(sdp);
 498                 error = -EIO;
 499                 goto fail;
 500         }
 501
 502         /*  Initialize some head of the log stuff  */
 503         sdp->sd_log_sequence = head.lh_sequence + 1;
 504         gfs2_log_pointers_init(sdp, head.lh_blkno);
 505
 506         error = gfs2_unlinked_init(sdp);
 507         if (error)
 508                 goto fail;
 509         error = gfs2_quota_init(sdp);
 510         if (error)
 511                 goto fail_unlinked;
 512
 513         set_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 514
 515         gfs2_glock_dq_uninit(&t_gh);
 516
 517         return 0;
 518
 519  fail_unlinked:
 520         gfs2_unlinked_cleanup(sdp);
 521
 522  fail:
 523         t_gh.gh_flags |= GL_NOCACHE;
 524         gfs2_glock_dq_uninit(&t_gh);
 525
 526         return error;
 527 }
 528
 529 /**
 530  * gfs2_make_fs_ro - Turn a Read-Write FS into a Read-Only one
 531  * @sdp: the filesystem
 532  *
 533  * Returns: errno
 534  */
 535
 536 int gfs2_make_fs_ro(struct gfs2_sbd *sdp)
 537 {
 538         struct gfs2_holder t_gh;
 539         int error;
 540
 541         gfs2_unlinked_dealloc(sdp);
 542         gfs2_quota_sync(sdp);
 543         gfs2_statfs_sync(sdp);
 544
 545         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
 546                                 GL_LOCAL_EXCL | GL_NEVER_RECURSE | GL_NOCACHE,
 547                                 &t_gh);
 548         if (error && !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
 549                 return error;
 550
 551         gfs2_meta_syncfs(sdp);
 552         gfs2_log_shutdown(sdp);
 553
 554         clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 555
 556         if (t_gh.gh_gl)
 557                 gfs2_glock_dq_uninit(&t_gh);
 558
 559         gfs2_unlinked_cleanup(sdp);
 560         gfs2_quota_cleanup(sdp);
 561
 562         return error;
 563 }
 564
 565 int gfs2_statfs_init(struct gfs2_sbd *sdp)
 566 {
 567         struct gfs2_inode *m_ip = sdp->sd_statfs_inode->u.generic_ip;
 568         struct gfs2_statfs_change *m_sc = &sdp->sd_statfs_master;
 569         struct gfs2_inode *l_ip = sdp->sd_sc_inode->u.generic_ip;
 570         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 571         struct buffer_head *m_bh, *l_bh;
 572         struct gfs2_holder gh;
 573         int error;
 574
 575         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 576                                    &gh);
 577         if (error)
 578                 return error;
 579
 580         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 581         if (error)
 582                 goto out;
 583
 584         if (sdp->sd_args.ar_spectator) {
 585                 spin_lock(&sdp->sd_statfs_spin);
 586                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 587                                       sizeof(struct gfs2_dinode));
 588                 spin_unlock(&sdp->sd_statfs_spin);
 589         } else {
 590                 error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 591                 if (error)
 592                         goto out_m_bh;
 593
 594                 spin_lock(&sdp->sd_statfs_spin);
 595                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 596                                       sizeof(struct gfs2_dinode));
 597                 gfs2_statfs_change_in(l_sc, l_bh->b_data +
 598                                       sizeof(struct gfs2_dinode));
 599                 spin_unlock(&sdp->sd_statfs_spin);
 600
 601                 brelse(l_bh);
 602         }
 603
 604  out_m_bh:
 605         brelse(m_bh);
 606
 607  out:
 608         gfs2_glock_dq_uninit(&gh);
 609
 610         return 0;
 611 }
 612
 613 void gfs2_statfs_change(struct gfs2_sbd *sdp, int64_t total, int64_t free,
 614                         int64_t dinodes)
 615 {
 616         struct gfs2_inode *l_ip = sdp->sd_sc_inode->u.generic_ip;
 617         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 618         struct buffer_head *l_bh;
 619         int error;
 620
 621         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 622         if (error)
 623                 return;
 624
 625         mutex_lock(&sdp->sd_statfs_mutex);
 626         gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
 627         mutex_unlock(&sdp->sd_statfs_mutex);
 628
 629         spin_lock(&sdp->sd_statfs_spin);
 630         l_sc->sc_total += total;
 631         l_sc->sc_free += free;
 632         l_sc->sc_dinodes += dinodes;
 633         gfs2_statfs_change_out(l_sc, l_bh->b_data +
 634                                sizeof(struct gfs2_dinode));
 635         spin_unlock(&sdp->sd_statfs_spin);
 636
 637         brelse(l_bh);
 638 }
 639
 640 int gfs2_statfs_sync(struct gfs2_sbd *sdp)
 641 {
 642         struct gfs2_inode *m_ip = sdp->sd_statfs_inode->u.generic_ip;
 643         struct gfs2_inode *l_ip = sdp->sd_sc_inode->u.generic_ip;
 644         struct gfs2_statfs_change *m_sc = &sdp->sd_statfs_master;
 645         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 646         struct gfs2_holder gh;
 647         struct buffer_head *m_bh, *l_bh;
 648         int error;
 649
 650         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 651                                    &gh);
 652         if (error)
 653                 return error;
 654
 655         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 656         if (error)
 657                 goto out;
 658
 659         spin_lock(&sdp->sd_statfs_spin);
 660         gfs2_statfs_change_in(m_sc, m_bh->b_data +
 661                               sizeof(struct gfs2_dinode));
 662         if (!l_sc->sc_total && !l_sc->sc_free && !l_sc->sc_dinodes) {
 663                 spin_unlock(&sdp->sd_statfs_spin);
 664                 goto out_bh;
 665         }
 666         spin_unlock(&sdp->sd_statfs_spin);
 667
 668         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 669         if (error)
 670                 goto out_bh;
 671
 672         error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
 673         if (error)
 674                 goto out_bh2;
 675
 676         mutex_lock(&sdp->sd_statfs_mutex);
 677         gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
 678         mutex_unlock(&sdp->sd_statfs_mutex);
 679
 680         spin_lock(&sdp->sd_statfs_spin);
 681         m_sc->sc_total += l_sc->sc_total;
 682         m_sc->sc_free += l_sc->sc_free;
 683         m_sc->sc_dinodes += l_sc->sc_dinodes;
 684         memset(l_sc, 0, sizeof(struct gfs2_statfs_change));
 685         memset(l_bh->b_data + sizeof(struct gfs2_dinode),
 686                0, sizeof(struct gfs2_statfs_change));
 687         spin_unlock(&sdp->sd_statfs_spin);
 688
 689         gfs2_trans_add_bh(m_ip->i_gl, m_bh, 1);
 690         gfs2_statfs_change_out(m_sc, m_bh->b_data + sizeof(struct gfs2_dinode));
 691
 692         gfs2_trans_end(sdp);
 693
 694  out_bh2:
 695         brelse(l_bh);
 696
 697  out_bh:
 698         brelse(m_bh);
 699
 700  out:
 701         gfs2_glock_dq_uninit(&gh);
 702
 703         return error;
 704 }
 705
 706 /**
 707  * gfs2_statfs_i - Do a statfs
 708  * @sdp: the filesystem
 709  * @sg: the sg structure
 710  *
 711  * Returns: errno
 712  */
 713
 714 int gfs2_statfs_i(struct gfs2_sbd *sdp, struct gfs2_statfs_change *sc)
 715 {
 716         struct gfs2_statfs_change *m_sc = &sdp->sd_statfs_master;
 717         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 718
 719         spin_lock(&sdp->sd_statfs_spin);
 720
 721         *sc = *m_sc;
 722         sc->sc_total += l_sc->sc_total;
 723         sc->sc_free += l_sc->sc_free;
 724         sc->sc_dinodes += l_sc->sc_dinodes;
 725
 726         spin_unlock(&sdp->sd_statfs_spin);
 727
 728         if (sc->sc_free < 0)
 729                 sc->sc_free = 0;
 730         if (sc->sc_free > sc->sc_total)
 731                 sc->sc_free = sc->sc_total;
 732         if (sc->sc_dinodes < 0)
 733                 sc->sc_dinodes = 0;
 734
 735         return 0;
 736 }
 737
 738 /**
 739  * statfs_fill - fill in the sg for a given RG
 740  * @rgd: the RG
 741  * @sc: the sc structure
 742  *
 743  * Returns: 0 on success, -ESTALE if the LVB is invalid
 744  */
 745
 746 static int statfs_slow_fill(struct gfs2_rgrpd *rgd,
 747                             struct gfs2_statfs_change *sc)
 748 {
 749         gfs2_rgrp_verify(rgd);
 750         sc->sc_total += rgd->rd_ri.ri_data;
 751         sc->sc_free += rgd->rd_rg.rg_free;
 752         sc->sc_dinodes += rgd->rd_rg.rg_dinodes;
 753         return 0;
 754 }
 755
 756 /**
 757  * gfs2_statfs_slow - Stat a filesystem using asynchronous locking
 758  * @sdp: the filesystem
 759  * @sc: the sc info that will be returned
 760  *
 761  * Any error (other than a signal) will cause this routine to fall back
 762  * to the synchronous version.
 763  *
 764  * FIXME: This really shouldn't busy wait like this.
 765  *
 766  * Returns: errno
 767  */
 768
 769 int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change *sc)
 770 {
 771         struct gfs2_holder ri_gh;
 772         struct gfs2_rgrpd *rgd_next;
 773         struct gfs2_holder *gha, *gh;
 774         unsigned int slots = 64;
 775         unsigned int x;
 776         int done;
 777         int error = 0, err;
 778
 779         memset(sc, 0, sizeof(struct gfs2_statfs_change));
 780         gha = kcalloc(slots, sizeof(struct gfs2_holder), GFP_KERNEL);
 781         if (!gha)
 782                 return -ENOMEM;
 783
 784         error = gfs2_rindex_hold(sdp, &ri_gh);
 785         if (error)
 786                 goto out;
 787
 788         rgd_next = gfs2_rgrpd_get_first(sdp);
 789
 790         for (;;) {
 791                 done = 1;
 792
 793                 for (x = 0; x < slots; x++) {
 794                         gh = gha + x;
 795
 796                         if (gh->gh_gl && gfs2_glock_poll(gh)) {
 797                                 err = gfs2_glock_wait(gh);
 798                                 if (err) {
 799                                         gfs2_holder_uninit(gh);
 800                                         error = err;
 801                                 } else {
 802                                         if (!error)
 803                                                 error = statfs_slow_fill(
 804                                                         gh->gh_gl->gl_object, sc);
 805                                         gfs2_glock_dq_uninit(gh);
 806                                 }
 807                         }
 808
 809                         if (gh->gh_gl)
 810                                 done = 0;
 811                         else if (rgd_next && !error) {
 812                                 error = gfs2_glock_nq_init(rgd_next->rd_gl,
 813                                                            LM_ST_SHARED,
 814                                                            GL_ASYNC,
 815                                                            gh);
 816                                 rgd_next = gfs2_rgrpd_get_next(rgd_next);
 817                                 done = 0;
 818                         }
 819
 820                         if (signal_pending(current))
 821                                 error = -ERESTARTSYS;
 822                 }
 823
 824                 if (done)
 825                         break;
 826
 827                 yield();
 828         }
 829
 830         gfs2_glock_dq_uninit(&ri_gh);
 831
 832  out:
 833         kfree(gha);
 834
 835         return error;
 836 }
 837
 838 struct lfcc {
 839         struct list_head list;
 840         struct gfs2_holder gh;
 841 };
 842
 843 /**
 844  * gfs2_lock_fs_check_clean - Stop all writes to the FS and check that all
 845  *                            journals are clean
 846  * @sdp: the file system
 847  * @state: the state to put the transaction lock into
 848  * @t_gh: the hold on the transaction lock
 849  *
 850  * Returns: errno
 851  */
 852
 853 int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp, struct gfs2_holder *t_gh)
 854 {
 855         struct gfs2_inode *ip;
 856         struct gfs2_holder ji_gh;
 857         struct gfs2_jdesc *jd;
 858         struct lfcc *lfcc;
 859         LIST_HEAD(list);
 860         struct gfs2_log_header lh;
 861         int error;
 862
 863         error = gfs2_jindex_hold(sdp, &ji_gh);
 864         if (error)
 865                 return error;
 866
 867         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 868                 lfcc = kmalloc(sizeof(struct lfcc), GFP_KERNEL);
 869                 if (!lfcc) {
 870                         error = -ENOMEM;
 871                         goto out;
 872                 }
 873                 ip = jd->jd_inode->u.generic_ip;
 874                 error = gfs2_glock_nq_init(ip->i_gl,
 875                                            LM_ST_SHARED, 0,
 876                                            &lfcc->gh);
 877                 if (error) {
 878                         kfree(lfcc);
 879                         goto out;
 880                 }
 881                 list_add(&lfcc->list, &list);
 882         }
 883
 884         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_DEFERRED,
 885                                LM_FLAG_PRIORITY | GL_NEVER_RECURSE | GL_NOCACHE,
 886                                t_gh);
 887
 888         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 889                 error = gfs2_jdesc_check(jd);
 890                 if (error)
 891                         break;
 892                 error = gfs2_find_jhead(jd, &lh);
 893                 if (error)
 894                         break;
 895                 if (!(lh.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 896                         error = -EBUSY;
 897                         break;
 898                 }
 899         }
 900
 901         if (error)
 902                 gfs2_glock_dq_uninit(t_gh);
 903
 904  out:
 905         while (!list_empty(&list)) {
 906                 lfcc = list_entry(list.next, struct lfcc, list);
 907                 list_del(&lfcc->list);
 908                 gfs2_glock_dq_uninit(&lfcc->gh);
 909                 kfree(lfcc);
 910         }
 911         gfs2_glock_dq_uninit(&ji_gh);
 912
 913         return error;
 914 }
 915
 916 /**
 917  * gfs2_freeze_fs - freezes the file system
 918  * @sdp: the file system
 919  *
 920  * This function flushes data and meta data for all machines by
 921  * aquiring the transaction log exclusively.  All journals are
 922  * ensured to be in a clean state as well.
 923  *
 924  * Returns: errno
 925  */
 926
 927 int gfs2_freeze_fs(struct gfs2_sbd *sdp)
 928 {
 929         int error = 0;
 930
 931         mutex_lock(&sdp->sd_freeze_lock);
 932
 933         if (!sdp->sd_freeze_count++) {
 934                 error = gfs2_lock_fs_check_clean(sdp, &sdp->sd_freeze_gh);
 935                 if (error)
 936                         sdp->sd_freeze_count--;
 937         }
 938
 939         mutex_unlock(&sdp->sd_freeze_lock);
 940
 941         return error;
 942 }
 943
 944 /**
 945  * gfs2_unfreeze_fs - unfreezes the file system
 946  * @sdp: the file system
 947  *
 948  * This function allows the file system to proceed by unlocking
 949  * the exclusively held transaction lock.  Other GFS2 nodes are
 950  * now free to acquire the lock shared and go on with their lives.
 951  *
 952  */
 953
 954 void gfs2_unfreeze_fs(struct gfs2_sbd *sdp)
 955 {
 956         mutex_lock(&sdp->sd_freeze_lock);
 957
 958         if (sdp->sd_freeze_count && !--sdp->sd_freeze_count)
 959                 gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
 960
 961         mutex_unlock(&sdp->sd_freeze_lock);
 962 }
 963