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 version 2.
   8  */
   9
  10 #include <linux/sched.h>
  11 #include <linux/slab.h>
  12 #include <linux/spinlock.h>
  13 #include <linux/completion.h>
  14 #include <linux/buffer_head.h>
  15 #include <linux/crc32.h>
  16 #include <linux/gfs2_ondisk.h>
  17 #include <linux/bio.h>
  18 #include <linux/lm_interface.h>
  19
  20 #include "gfs2.h"
  21 #include "incore.h"
  22 #include "bmap.h"
  23 #include "dir.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 "util.h"
  35
  36 static const u32 gfs2_old_fs_formats[] = {
  37         0
  38 };
  39
  40 static const u32 gfs2_old_multihost_formats[] = {
  41         0
  42 };
  43
  44 /**
  45  * gfs2_tune_init - Fill a gfs2_tune structure with default values
  46  * @gt: tune
  47  *
  48  */
  49
  50 void gfs2_tune_init(struct gfs2_tune *gt)
  51 {
  52         spin_lock_init(&gt->gt_spin);
  53
  54         gt->gt_ilimit = 100;
  55         gt->gt_ilimit_tries = 3;
  56         gt->gt_ilimit_min = 1;
  57         gt->gt_demote_secs = 300;
  58         gt->gt_incore_log_blocks = 1024;
  59         gt->gt_log_flush_secs = 60;
  60         gt->gt_jindex_refresh_secs = 60;
  61         gt->gt_scand_secs = 15;
  62         gt->gt_recoverd_secs = 60;
  63         gt->gt_logd_secs = 1;
  64         gt->gt_quotad_secs = 5;
  65         gt->gt_quota_simul_sync = 64;
  66         gt->gt_quota_warn_period = 10;
  67         gt->gt_quota_scale_num = 1;
  68         gt->gt_quota_scale_den = 1;
  69         gt->gt_quota_cache_secs = 300;
  70         gt->gt_quota_quantum = 60;
  71         gt->gt_atime_quantum = 3600;
  72         gt->gt_new_files_jdata = 0;
  73         gt->gt_new_files_directio = 0;
  74         gt->gt_max_atomic_write = 4 << 20;
  75         gt->gt_max_readahead = 1 << 18;
  76         gt->gt_lockdump_size = 131072;
  77         gt->gt_stall_secs = 600;
  78         gt->gt_complain_secs = 10;
  79         gt->gt_reclaim_limit = 5000;
  80         gt->gt_entries_per_readdir = 32;
  81         gt->gt_prefetch_secs = 10;
  82         gt->gt_greedy_default = HZ / 10;
  83         gt->gt_greedy_quantum = HZ / 40;
  84         gt->gt_greedy_max = HZ / 4;
  85         gt->gt_statfs_quantum = 30;
  86         gt->gt_statfs_slow = 0;
  87 }
  88
  89 /**
  90  * gfs2_check_sb - Check superblock
  91  * @sdp: the filesystem
  92  * @sb: The superblock
  93  * @silent: Don't print a message if the check fails
  94  *
  95  * Checks the version code of the FS is one that we understand how to
  96  * read and that the sizes of the various on-disk structures have not
  97  * changed.
  98  */
  99
 100 int gfs2_check_sb(struct gfs2_sbd *sdp, struct gfs2_sb *sb, int silent)
 101 {
 102         unsigned int x;
 103
 104         if (sb->sb_header.mh_magic != GFS2_MAGIC ||
 105             sb->sb_header.mh_type != GFS2_METATYPE_SB) {
 106                 if (!silent)
 107                         printk(KERN_WARNING "GFS2: not a GFS2 filesystem\n");
 108                 return -EINVAL;
 109         }
 110
 111         /*  If format numbers match exactly, we're done.  */
 112
 113         if (sb->sb_fs_format == GFS2_FORMAT_FS &&
 114             sb->sb_multihost_format == GFS2_FORMAT_MULTI)
 115                 return 0;
 116
 117         if (sb->sb_fs_format != GFS2_FORMAT_FS) {
 118                 for (x = 0; gfs2_old_fs_formats[x]; x++)
 119                         if (gfs2_old_fs_formats[x] == sb->sb_fs_format)
 120                                 break;
 121
 122                 if (!gfs2_old_fs_formats[x]) {
 123                         printk(KERN_WARNING
 124                                "GFS2: code version (%u, %u) is incompatible "
 125                                "with ondisk format (%u, %u)\n",
 126                                GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
 127                                sb->sb_fs_format, sb->sb_multihost_format);
 128                         printk(KERN_WARNING
 129                                "GFS2: I don't know how to upgrade this FS\n");
 130                         return -EINVAL;
 131                 }
 132         }
 133
 134         if (sb->sb_multihost_format != GFS2_FORMAT_MULTI) {
 135                 for (x = 0; gfs2_old_multihost_formats[x]; x++)
 136                         if (gfs2_old_multihost_formats[x] ==
 137                             sb->sb_multihost_format)
 138                                 break;
 139
 140                 if (!gfs2_old_multihost_formats[x]) {
 141                         printk(KERN_WARNING
 142                                "GFS2: code version (%u, %u) is incompatible "
 143                                "with ondisk format (%u, %u)\n",
 144                                GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
 145                                sb->sb_fs_format, sb->sb_multihost_format);
 146                         printk(KERN_WARNING
 147                                "GFS2: I don't know how to upgrade this FS\n");
 148                         return -EINVAL;
 149                 }
 150         }
 151
 152         if (!sdp->sd_args.ar_upgrade) {
 153                 printk(KERN_WARNING
 154                        "GFS2: code version (%u, %u) is incompatible "
 155                        "with ondisk format (%u, %u)\n",
 156                        GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
 157                        sb->sb_fs_format, sb->sb_multihost_format);
 158                 printk(KERN_INFO
 159                        "GFS2: Use the \"upgrade\" mount option to upgrade "
 160                        "the FS\n");
 161                 printk(KERN_INFO "GFS2: See the manual for more details\n");
 162                 return -EINVAL;
 163         }
 164
 165         return 0;
 166 }
 167
 168
 169 static int end_bio_io_page(struct bio *bio, unsigned int bytes_done, int error)
 170 {
 171         struct page *page = bio->bi_private;
 172         if (bio->bi_size)
 173                 return 1;
 174
 175         if (!error)
 176                 SetPageUptodate(page);
 177         else
 178                 printk(KERN_WARNING "gfs2: error %d reading superblock\n", error);
 179         unlock_page(page);
 180         return 0;
 181 }
 182
 183 static struct page *gfs2_read_super(struct super_block *sb, sector_t sector)
 184 {
 185         struct page *page;
 186         struct bio *bio;
 187
 188         page = alloc_page(GFP_KERNEL);
 189         if (unlikely(!page))
 190                 return NULL;
 191
 192         ClearPageUptodate(page);
 193         ClearPageDirty(page);
 194         lock_page(page);
 195
 196         bio = bio_alloc(GFP_KERNEL, 1);
 197         if (unlikely(!bio)) {
 198                 __free_page(page);
 199                 return NULL;
 200         }
 201
 202         bio->bi_sector = sector;
 203         bio->bi_bdev = sb->s_bdev;
 204         bio_add_page(bio, page, PAGE_SIZE, 0);
 205
 206         bio->bi_end_io = end_bio_io_page;
 207         bio->bi_private = page;
 208         submit_bio(READ_SYNC, bio);
 209         wait_on_page_locked(page);
 210         bio_put(bio);
 211         if (!PageUptodate(page)) {
 212                 __free_page(page);
 213                 return NULL;
 214         }
 215         return page;
 216 }
 217
 218 /**
 219  * gfs2_read_sb - Read super block
 220  * @sdp: The GFS2 superblock
 221  * @gl: the glock for the superblock (assumed to be held)
 222  * @silent: Don't print message if mount fails
 223  *
 224  */
 225
 226 int gfs2_read_sb(struct gfs2_sbd *sdp, struct gfs2_glock *gl, int silent)
 227 {
 228         u32 hash_blocks, ind_blocks, leaf_blocks;
 229         u32 tmp_blocks;
 230         unsigned int x;
 231         int error;
 232         struct page *page;
 233         char *sb;
 234
 235         page = gfs2_read_super(sdp->sd_vfs, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift);
 236         if (!page) {
 237                 if (!silent)
 238                         fs_err(sdp, "can't read superblock\n");
 239                 return -EIO;
 240         }
 241         sb = kmap(page);
 242         gfs2_sb_in(&sdp->sd_sb, sb);
 243         kunmap(page);
 244         __free_page(page);
 245
 246         error = gfs2_check_sb(sdp, &sdp->sd_sb, silent);
 247         if (error)
 248                 return error;
 249
 250         sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
 251                                GFS2_BASIC_BLOCK_SHIFT;
 252         sdp->sd_fsb2bb = 1 << sdp->sd_fsb2bb_shift;
 253         sdp->sd_diptrs = (sdp->sd_sb.sb_bsize -
 254                           sizeof(struct gfs2_dinode)) / sizeof(u64);
 255         sdp->sd_inptrs = (sdp->sd_sb.sb_bsize -
 256                           sizeof(struct gfs2_meta_header)) / sizeof(u64);
 257         sdp->sd_jbsize = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header);
 258         sdp->sd_hash_bsize = sdp->sd_sb.sb_bsize / 2;
 259         sdp->sd_hash_bsize_shift = sdp->sd_sb.sb_bsize_shift - 1;
 260         sdp->sd_hash_ptrs = sdp->sd_hash_bsize / sizeof(u64);
 261         sdp->sd_qc_per_block = (sdp->sd_sb.sb_bsize -
 262                                 sizeof(struct gfs2_meta_header)) /
 263                                 sizeof(struct gfs2_quota_change);
 264
 265         /* Compute maximum reservation required to add a entry to a directory */
 266
 267         hash_blocks = DIV_ROUND_UP(sizeof(u64) * (1 << GFS2_DIR_MAX_DEPTH),
 268                              sdp->sd_jbsize);
 269
 270         ind_blocks = 0;
 271         for (tmp_blocks = hash_blocks; tmp_blocks > sdp->sd_diptrs;) {
 272                 tmp_blocks = DIV_ROUND_UP(tmp_blocks, sdp->sd_inptrs);
 273                 ind_blocks += tmp_blocks;
 274         }
 275
 276         leaf_blocks = 2 + GFS2_DIR_MAX_DEPTH;
 277
 278         sdp->sd_max_dirres = hash_blocks + ind_blocks + leaf_blocks;
 279
 280         sdp->sd_heightsize[0] = sdp->sd_sb.sb_bsize -
 281                                 sizeof(struct gfs2_dinode);
 282         sdp->sd_heightsize[1] = sdp->sd_sb.sb_bsize * sdp->sd_diptrs;
 283         for (x = 2;; x++) {
 284                 u64 space, d;
 285                 u32 m;
 286
 287                 space = sdp->sd_heightsize[x - 1] * sdp->sd_inptrs;
 288                 d = space;
 289                 m = do_div(d, sdp->sd_inptrs);
 290
 291                 if (d != sdp->sd_heightsize[x - 1] || m)
 292                         break;
 293                 sdp->sd_heightsize[x] = space;
 294         }
 295         sdp->sd_max_height = x;
 296         gfs2_assert(sdp, sdp->sd_max_height <= GFS2_MAX_META_HEIGHT);
 297
 298         sdp->sd_jheightsize[0] = sdp->sd_sb.sb_bsize -
 299                                  sizeof(struct gfs2_dinode);
 300         sdp->sd_jheightsize[1] = sdp->sd_jbsize * sdp->sd_diptrs;
 301         for (x = 2;; x++) {
 302                 u64 space, d;
 303                 u32 m;
 304
 305                 space = sdp->sd_jheightsize[x - 1] * sdp->sd_inptrs;
 306                 d = space;
 307                 m = do_div(d, sdp->sd_inptrs);
 308
 309                 if (d != sdp->sd_jheightsize[x - 1] || m)
 310                         break;
 311                 sdp->sd_jheightsize[x] = space;
 312         }
 313         sdp->sd_max_jheight = x;
 314         gfs2_assert(sdp, sdp->sd_max_jheight <= GFS2_MAX_META_HEIGHT);
 315
 316         return 0;
 317 }
 318
 319 /**
 320  * gfs2_jindex_hold - Grab a lock on the jindex
 321  * @sdp: The GFS2 superblock
 322  * @ji_gh: the holder for the jindex glock
 323  *
 324  * This is very similar to the gfs2_rindex_hold() function, except that
 325  * in general we hold the jindex lock for longer periods of time and
 326  * we grab it far less frequently (in general) then the rgrp lock.
 327  *
 328  * Returns: errno
 329  */
 330
 331 int gfs2_jindex_hold(struct gfs2_sbd *sdp, struct gfs2_holder *ji_gh)
 332 {
 333         struct gfs2_inode *dip = GFS2_I(sdp->sd_jindex);
 334         struct qstr name;
 335         char buf[20];
 336         struct gfs2_jdesc *jd;
 337         int error;
 338
 339         name.name = buf;
 340
 341         mutex_lock(&sdp->sd_jindex_mutex);
 342
 343         for (;;) {
 344                 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED,
 345                                            GL_LOCAL_EXCL, ji_gh);
 346                 if (error)
 347                         break;
 348
 349                 name.len = sprintf(buf, "journal%u", sdp->sd_journals);
 350                 name.hash = gfs2_disk_hash(name.name, name.len);
 351
 352                 error = gfs2_dir_search(sdp->sd_jindex, &name, NULL, NULL);
 353                 if (error == -ENOENT) {
 354                         error = 0;
 355                         break;
 356                 }
 357
 358                 gfs2_glock_dq_uninit(ji_gh);
 359
 360                 if (error)
 361                         break;
 362
 363                 error = -ENOMEM;
 364                 jd = kzalloc(sizeof(struct gfs2_jdesc), GFP_KERNEL);
 365                 if (!jd)
 366                         break;
 367
 368                 jd->jd_inode = gfs2_lookupi(sdp->sd_jindex, &name, 1, NULL);
 369                 if (!jd->jd_inode || IS_ERR(jd->jd_inode)) {
 370                         if (!jd->jd_inode)
 371                                 error = -ENOENT;
 372                         else
 373                                 error = PTR_ERR(jd->jd_inode);
 374                         kfree(jd);
 375                         break;
 376                 }
 377
 378                 spin_lock(&sdp->sd_jindex_spin);
 379                 jd->jd_jid = sdp->sd_journals++;
 380                 list_add_tail(&jd->jd_list, &sdp->sd_jindex_list);
 381                 spin_unlock(&sdp->sd_jindex_spin);
 382         }
 383
 384         mutex_unlock(&sdp->sd_jindex_mutex);
 385
 386         return error;
 387 }
 388
 389 /**
 390  * gfs2_jindex_free - Clear all the journal index information
 391  * @sdp: The GFS2 superblock
 392  *
 393  */
 394
 395 void gfs2_jindex_free(struct gfs2_sbd *sdp)
 396 {
 397         struct list_head list;
 398         struct gfs2_jdesc *jd;
 399
 400         spin_lock(&sdp->sd_jindex_spin);
 401         list_add(&list, &sdp->sd_jindex_list);
 402         list_del_init(&sdp->sd_jindex_list);
 403         sdp->sd_journals = 0;
 404         spin_unlock(&sdp->sd_jindex_spin);
 405
 406         while (!list_empty(&list)) {
 407                 jd = list_entry(list.next, struct gfs2_jdesc, jd_list);
 408                 list_del(&jd->jd_list);
 409                 iput(jd->jd_inode);
 410                 kfree(jd);
 411         }
 412 }
 413
 414 static struct gfs2_jdesc *jdesc_find_i(struct list_head *head, unsigned int jid)
 415 {
 416         struct gfs2_jdesc *jd;
 417         int found = 0;
 418
 419         list_for_each_entry(jd, head, jd_list) {
 420                 if (jd->jd_jid == jid) {
 421                         found = 1;
 422                         break;
 423                 }
 424         }
 425
 426         if (!found)
 427                 jd = NULL;
 428
 429         return jd;
 430 }
 431
 432 struct gfs2_jdesc *gfs2_jdesc_find(struct gfs2_sbd *sdp, unsigned int jid)
 433 {
 434         struct gfs2_jdesc *jd;
 435
 436         spin_lock(&sdp->sd_jindex_spin);
 437         jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
 438         spin_unlock(&sdp->sd_jindex_spin);
 439
 440         return jd;
 441 }
 442
 443 void gfs2_jdesc_make_dirty(struct gfs2_sbd *sdp, unsigned int jid)
 444 {
 445         struct gfs2_jdesc *jd;
 446
 447         spin_lock(&sdp->sd_jindex_spin);
 448         jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
 449         if (jd)
 450                 jd->jd_dirty = 1;
 451         spin_unlock(&sdp->sd_jindex_spin);
 452 }
 453
 454 struct gfs2_jdesc *gfs2_jdesc_find_dirty(struct gfs2_sbd *sdp)
 455 {
 456         struct gfs2_jdesc *jd;
 457         int found = 0;
 458
 459         spin_lock(&sdp->sd_jindex_spin);
 460
 461         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 462                 if (jd->jd_dirty) {
 463                         jd->jd_dirty = 0;
 464                         found = 1;
 465                         break;
 466                 }
 467         }
 468         spin_unlock(&sdp->sd_jindex_spin);
 469
 470         if (!found)
 471                 jd = NULL;
 472
 473         return jd;
 474 }
 475
 476 int gfs2_jdesc_check(struct gfs2_jdesc *jd)
 477 {
 478         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
 479         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 480         int ar;
 481         int error;
 482
 483         if (ip->i_di.di_size < (8 << 20) || ip->i_di.di_size > (1 << 30) ||
 484             (ip->i_di.di_size & (sdp->sd_sb.sb_bsize - 1))) {
 485                 gfs2_consist_inode(ip);
 486                 return -EIO;
 487         }
 488         jd->jd_blocks = ip->i_di.di_size >> sdp->sd_sb.sb_bsize_shift;
 489
 490         error = gfs2_write_alloc_required(ip, 0, ip->i_di.di_size, &ar);
 491         if (!error && ar) {
 492                 gfs2_consist_inode(ip);
 493                 error = -EIO;
 494         }
 495
 496         return error;
 497 }
 498
 499 /**
 500  * gfs2_make_fs_rw - Turn a Read-Only FS into a Read-Write one
 501  * @sdp: the filesystem
 502  *
 503  * Returns: errno
 504  */
 505
 506 int gfs2_make_fs_rw(struct gfs2_sbd *sdp)
 507 {
 508         struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
 509         struct gfs2_glock *j_gl = ip->i_gl;
 510         struct gfs2_holder t_gh;
 511         struct gfs2_log_header head;
 512         int error;
 513
 514         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
 515                                    GL_LOCAL_EXCL, &t_gh);
 516         if (error)
 517                 return error;
 518
 519         gfs2_meta_cache_flush(ip);
 520         j_gl->gl_ops->go_inval(j_gl, DIO_METADATA | DIO_DATA);
 521
 522         error = gfs2_find_jhead(sdp->sd_jdesc, &head);
 523         if (error)
 524                 goto fail;
 525
 526         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 527                 gfs2_consist(sdp);
 528                 error = -EIO;
 529                 goto fail;
 530         }
 531
 532         /*  Initialize some head of the log stuff  */
 533         sdp->sd_log_sequence = head.lh_sequence + 1;
 534         gfs2_log_pointers_init(sdp, head.lh_blkno);
 535
 536         error = gfs2_quota_init(sdp);
 537         if (error)
 538                 goto fail;
 539
 540         set_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 541
 542         gfs2_glock_dq_uninit(&t_gh);
 543
 544         return 0;
 545
 546 fail:
 547         t_gh.gh_flags |= GL_NOCACHE;
 548         gfs2_glock_dq_uninit(&t_gh);
 549
 550         return error;
 551 }
 552
 553 /**
 554  * gfs2_make_fs_ro - Turn a Read-Write FS into a Read-Only one
 555  * @sdp: the filesystem
 556  *
 557  * Returns: errno
 558  */
 559
 560 int gfs2_make_fs_ro(struct gfs2_sbd *sdp)
 561 {
 562         struct gfs2_holder t_gh;
 563         int error;
 564
 565         gfs2_quota_sync(sdp);
 566         gfs2_statfs_sync(sdp);
 567
 568         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
 569                                 GL_LOCAL_EXCL | GL_NOCACHE,
 570                                 &t_gh);
 571         if (error && !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
 572                 return error;
 573
 574         gfs2_meta_syncfs(sdp);
 575         gfs2_log_shutdown(sdp);
 576
 577         clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 578
 579         if (t_gh.gh_gl)
 580                 gfs2_glock_dq_uninit(&t_gh);
 581
 582         gfs2_quota_cleanup(sdp);
 583
 584         return error;
 585 }
 586
 587 int gfs2_statfs_init(struct gfs2_sbd *sdp)
 588 {
 589         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 590         struct gfs2_statfs_change *m_sc = &sdp->sd_statfs_master;
 591         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 592         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 593         struct buffer_head *m_bh, *l_bh;
 594         struct gfs2_holder gh;
 595         int error;
 596
 597         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 598                                    &gh);
 599         if (error)
 600                 return error;
 601
 602         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 603         if (error)
 604                 goto out;
 605
 606         if (sdp->sd_args.ar_spectator) {
 607                 spin_lock(&sdp->sd_statfs_spin);
 608                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 609                                       sizeof(struct gfs2_dinode));
 610                 spin_unlock(&sdp->sd_statfs_spin);
 611         } else {
 612                 error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 613                 if (error)
 614                         goto out_m_bh;
 615
 616                 spin_lock(&sdp->sd_statfs_spin);
 617                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 618                                       sizeof(struct gfs2_dinode));
 619                 gfs2_statfs_change_in(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 out_m_bh:
 627         brelse(m_bh);
 628 out:
 629         gfs2_glock_dq_uninit(&gh);
 630         return 0;
 631 }
 632
 633 void gfs2_statfs_change(struct gfs2_sbd *sdp, s64 total, s64 free,
 634                         s64 dinodes)
 635 {
 636         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 637         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 638         struct buffer_head *l_bh;
 639         int error;
 640
 641         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 642         if (error)
 643                 return;
 644
 645         mutex_lock(&sdp->sd_statfs_mutex);
 646         gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
 647         mutex_unlock(&sdp->sd_statfs_mutex);
 648
 649         spin_lock(&sdp->sd_statfs_spin);
 650         l_sc->sc_total += total;
 651         l_sc->sc_free += free;
 652         l_sc->sc_dinodes += dinodes;
 653         gfs2_statfs_change_out(l_sc, l_bh->b_data + sizeof(struct gfs2_dinode));
 654         spin_unlock(&sdp->sd_statfs_spin);
 655
 656         brelse(l_bh);
 657 }
 658
 659 int gfs2_statfs_sync(struct gfs2_sbd *sdp)
 660 {
 661         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 662         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 663         struct gfs2_statfs_change *m_sc = &sdp->sd_statfs_master;
 664         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 665         struct gfs2_holder gh;
 666         struct buffer_head *m_bh, *l_bh;
 667         int error;
 668
 669         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 670                                    &gh);
 671         if (error)
 672                 return error;
 673
 674         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 675         if (error)
 676                 goto out;
 677
 678         spin_lock(&sdp->sd_statfs_spin);
 679         gfs2_statfs_change_in(m_sc, m_bh->b_data +
 680                               sizeof(struct gfs2_dinode));
 681         if (!l_sc->sc_total && !l_sc->sc_free && !l_sc->sc_dinodes) {
 682                 spin_unlock(&sdp->sd_statfs_spin);
 683                 goto out_bh;
 684         }
 685         spin_unlock(&sdp->sd_statfs_spin);
 686
 687         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 688         if (error)
 689                 goto out_bh;
 690
 691         error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
 692         if (error)
 693                 goto out_bh2;
 694
 695         mutex_lock(&sdp->sd_statfs_mutex);
 696         gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
 697         mutex_unlock(&sdp->sd_statfs_mutex);
 698
 699         spin_lock(&sdp->sd_statfs_spin);
 700         m_sc->sc_total += l_sc->sc_total;
 701         m_sc->sc_free += l_sc->sc_free;
 702         m_sc->sc_dinodes += l_sc->sc_dinodes;
 703         memset(l_sc, 0, sizeof(struct gfs2_statfs_change));
 704         memset(l_bh->b_data + sizeof(struct gfs2_dinode),
 705                0, sizeof(struct gfs2_statfs_change));
 706         spin_unlock(&sdp->sd_statfs_spin);
 707
 708         gfs2_trans_add_bh(m_ip->i_gl, m_bh, 1);
 709         gfs2_statfs_change_out(m_sc, m_bh->b_data + sizeof(struct gfs2_dinode));
 710
 711         gfs2_trans_end(sdp);
 712
 713 out_bh2:
 714         brelse(l_bh);
 715 out_bh:
 716         brelse(m_bh);
 717 out:
 718         gfs2_glock_dq_uninit(&gh);
 719         return error;
 720 }
 721
 722 /**
 723  * gfs2_statfs_i - Do a statfs
 724  * @sdp: the filesystem
 725  * @sg: the sg structure
 726  *
 727  * Returns: errno
 728  */
 729
 730 int gfs2_statfs_i(struct gfs2_sbd *sdp, struct gfs2_statfs_change *sc)
 731 {
 732         struct gfs2_statfs_change *m_sc = &sdp->sd_statfs_master;
 733         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 734
 735         spin_lock(&sdp->sd_statfs_spin);
 736
 737         *sc = *m_sc;
 738         sc->sc_total += l_sc->sc_total;
 739         sc->sc_free += l_sc->sc_free;
 740         sc->sc_dinodes += l_sc->sc_dinodes;
 741
 742         spin_unlock(&sdp->sd_statfs_spin);
 743
 744         if (sc->sc_free < 0)
 745                 sc->sc_free = 0;
 746         if (sc->sc_free > sc->sc_total)
 747                 sc->sc_free = sc->sc_total;
 748         if (sc->sc_dinodes < 0)
 749                 sc->sc_dinodes = 0;
 750
 751         return 0;
 752 }
 753
 754 /**
 755  * statfs_fill - fill in the sg for a given RG
 756  * @rgd: the RG
 757  * @sc: the sc structure
 758  *
 759  * Returns: 0 on success, -ESTALE if the LVB is invalid
 760  */
 761
 762 static int statfs_slow_fill(struct gfs2_rgrpd *rgd,
 763                             struct gfs2_statfs_change *sc)
 764 {
 765         gfs2_rgrp_verify(rgd);
 766         sc->sc_total += rgd->rd_ri.ri_data;
 767         sc->sc_free += rgd->rd_rg.rg_free;
 768         sc->sc_dinodes += rgd->rd_rg.rg_dinodes;
 769         return 0;
 770 }
 771
 772 /**
 773  * gfs2_statfs_slow - Stat a filesystem using asynchronous locking
 774  * @sdp: the filesystem
 775  * @sc: the sc info that will be returned
 776  *
 777  * Any error (other than a signal) will cause this routine to fall back
 778  * to the synchronous version.
 779  *
 780  * FIXME: This really shouldn't busy wait like this.
 781  *
 782  * Returns: errno
 783  */
 784
 785 int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change *sc)
 786 {
 787         struct gfs2_holder ri_gh;
 788         struct gfs2_rgrpd *rgd_next;
 789         struct gfs2_holder *gha, *gh;
 790         unsigned int slots = 64;
 791         unsigned int x;
 792         int done;
 793         int error = 0, err;
 794
 795         memset(sc, 0, sizeof(struct gfs2_statfs_change));
 796         gha = kcalloc(slots, sizeof(struct gfs2_holder), GFP_KERNEL);
 797         if (!gha)
 798                 return -ENOMEM;
 799
 800         error = gfs2_rindex_hold(sdp, &ri_gh);
 801         if (error)
 802                 goto out;
 803
 804         rgd_next = gfs2_rgrpd_get_first(sdp);
 805
 806         for (;;) {
 807                 done = 1;
 808
 809                 for (x = 0; x < slots; x++) {
 810                         gh = gha + x;
 811
 812                         if (gh->gh_gl && gfs2_glock_poll(gh)) {
 813                                 err = gfs2_glock_wait(gh);
 814                                 if (err) {
 815                                         gfs2_holder_uninit(gh);
 816                                         error = err;
 817                                 } else {
 818                                         if (!error)
 819                                                 error = statfs_slow_fill(
 820                                                         gh->gh_gl->gl_object, sc);
 821                                         gfs2_glock_dq_uninit(gh);
 822                                 }
 823                         }
 824
 825                         if (gh->gh_gl)
 826                                 done = 0;
 827                         else if (rgd_next && !error) {
 828                                 error = gfs2_glock_nq_init(rgd_next->rd_gl,
 829                                                            LM_ST_SHARED,
 830                                                            GL_ASYNC,
 831                                                            gh);
 832                                 rgd_next = gfs2_rgrpd_get_next(rgd_next);
 833                                 done = 0;
 834                         }
 835
 836                         if (signal_pending(current))
 837                                 error = -ERESTARTSYS;
 838                 }
 839
 840                 if (done)
 841                         break;
 842
 843                 yield();
 844         }
 845
 846         gfs2_glock_dq_uninit(&ri_gh);
 847
 848 out:
 849         kfree(gha);
 850         return error;
 851 }
 852
 853 struct lfcc {
 854         struct list_head list;
 855         struct gfs2_holder gh;
 856 };
 857
 858 /**
 859  * gfs2_lock_fs_check_clean - Stop all writes to the FS and check that all
 860  *                            journals are clean
 861  * @sdp: the file system
 862  * @state: the state to put the transaction lock into
 863  * @t_gh: the hold on the transaction lock
 864  *
 865  * Returns: errno
 866  */
 867
 868 static int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp,
 869                                     struct gfs2_holder *t_gh)
 870 {
 871         struct gfs2_inode *ip;
 872         struct gfs2_holder ji_gh;
 873         struct gfs2_jdesc *jd;
 874         struct lfcc *lfcc;
 875         LIST_HEAD(list);
 876         struct gfs2_log_header lh;
 877         int error;
 878
 879         error = gfs2_jindex_hold(sdp, &ji_gh);
 880         if (error)
 881                 return error;
 882
 883         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 884                 lfcc = kmalloc(sizeof(struct lfcc), GFP_KERNEL);
 885                 if (!lfcc) {
 886                         error = -ENOMEM;
 887                         goto out;
 888                 }
 889                 ip = GFS2_I(jd->jd_inode);
 890                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &lfcc->gh);
 891                 if (error) {
 892                         kfree(lfcc);
 893                         goto out;
 894                 }
 895                 list_add(&lfcc->list, &list);
 896         }
 897
 898         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_DEFERRED,
 899                                LM_FLAG_PRIORITY | GL_NOCACHE,
 900                                t_gh);
 901
 902         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 903                 error = gfs2_jdesc_check(jd);
 904                 if (error)
 905                         break;
 906                 error = gfs2_find_jhead(jd, &lh);
 907                 if (error)
 908                         break;
 909                 if (!(lh.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 910                         error = -EBUSY;
 911                         break;
 912                 }
 913         }
 914
 915         if (error)
 916                 gfs2_glock_dq_uninit(t_gh);
 917
 918 out:
 919         while (!list_empty(&list)) {
 920                 lfcc = list_entry(list.next, struct lfcc, list);
 921                 list_del(&lfcc->list);
 922                 gfs2_glock_dq_uninit(&lfcc->gh);
 923                 kfree(lfcc);
 924         }
 925         gfs2_glock_dq_uninit(&ji_gh);
 926         return error;
 927 }
 928
 929 /**
 930  * gfs2_freeze_fs - freezes the file system
 931  * @sdp: the file system
 932  *
 933  * This function flushes data and meta data for all machines by
 934  * aquiring the transaction log exclusively.  All journals are
 935  * ensured to be in a clean state as well.
 936  *
 937  * Returns: errno
 938  */
 939
 940 int gfs2_freeze_fs(struct gfs2_sbd *sdp)
 941 {
 942         int error = 0;
 943
 944         mutex_lock(&sdp->sd_freeze_lock);
 945
 946         if (!sdp->sd_freeze_count++) {
 947                 error = gfs2_lock_fs_check_clean(sdp, &sdp->sd_freeze_gh);
 948                 if (error)
 949                         sdp->sd_freeze_count--;
 950         }
 951
 952         mutex_unlock(&sdp->sd_freeze_lock);
 953
 954         return error;
 955 }
 956
 957 /**
 958  * gfs2_unfreeze_fs - unfreezes the file system
 959  * @sdp: the file system
 960  *
 961  * This function allows the file system to proceed by unlocking
 962  * the exclusively held transaction lock.  Other GFS2 nodes are
 963  * now free to acquire the lock shared and go on with their lives.
 964  *
 965  */
 966
 967 void gfs2_unfreeze_fs(struct gfs2_sbd *sdp)
 968 {
 969         mutex_lock(&sdp->sd_freeze_lock);
 970
 971         if (sdp->sd_freeze_count && !--sdp->sd_freeze_count)
 972                 gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
 973
 974         mutex_unlock(&sdp->sd_freeze_lock);
 975 }
 976