2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
 
   3  * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
 
   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.
 
  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>
 
  36 static const u32 gfs2_old_fs_formats[] = {
 
  40 static const u32 gfs2_old_multihost_formats[] = {
 
  45  * gfs2_tune_init - Fill a gfs2_tune structure with default values
 
  50 void gfs2_tune_init(struct gfs2_tune *gt)
 
  52         spin_lock_init(>->gt_spin);
 
  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_recoverd_secs = 60;
 
  63         gt->gt_quotad_secs = 5;
 
  64         gt->gt_quota_simul_sync = 64;
 
  65         gt->gt_quota_warn_period = 10;
 
  66         gt->gt_quota_scale_num = 1;
 
  67         gt->gt_quota_scale_den = 1;
 
  68         gt->gt_quota_cache_secs = 300;
 
  69         gt->gt_quota_quantum = 60;
 
  70         gt->gt_atime_quantum = 3600;
 
  71         gt->gt_new_files_jdata = 0;
 
  72         gt->gt_new_files_directio = 0;
 
  73         gt->gt_max_readahead = 1 << 18;
 
  74         gt->gt_lockdump_size = 131072;
 
  75         gt->gt_stall_secs = 600;
 
  76         gt->gt_complain_secs = 10;
 
  77         gt->gt_reclaim_limit = 5000;
 
  78         gt->gt_statfs_quantum = 30;
 
  79         gt->gt_statfs_slow = 0;
 
  83  * gfs2_check_sb - Check superblock
 
  84  * @sdp: the filesystem
 
  86  * @silent: Don't print a message if the check fails
 
  88  * Checks the version code of the FS is one that we understand how to
 
  89  * read and that the sizes of the various on-disk structures have not
 
  93 int gfs2_check_sb(struct gfs2_sbd *sdp, struct gfs2_sb_host *sb, int silent)
 
  97         if (sb->sb_magic != GFS2_MAGIC ||
 
  98             sb->sb_type != GFS2_METATYPE_SB) {
 
 100                         printk(KERN_WARNING "GFS2: not a GFS2 filesystem\n");
 
 104         /*  If format numbers match exactly, we're done.  */
 
 106         if (sb->sb_fs_format == GFS2_FORMAT_FS &&
 
 107             sb->sb_multihost_format == GFS2_FORMAT_MULTI)
 
 110         if (sb->sb_fs_format != GFS2_FORMAT_FS) {
 
 111                 for (x = 0; gfs2_old_fs_formats[x]; x++)
 
 112                         if (gfs2_old_fs_formats[x] == sb->sb_fs_format)
 
 115                 if (!gfs2_old_fs_formats[x]) {
 
 117                                "GFS2: code version (%u, %u) is incompatible "
 
 118                                "with ondisk format (%u, %u)\n",
 
 119                                GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
 
 120                                sb->sb_fs_format, sb->sb_multihost_format);
 
 122                                "GFS2: I don't know how to upgrade this FS\n");
 
 127         if (sb->sb_multihost_format != GFS2_FORMAT_MULTI) {
 
 128                 for (x = 0; gfs2_old_multihost_formats[x]; x++)
 
 129                         if (gfs2_old_multihost_formats[x] ==
 
 130                             sb->sb_multihost_format)
 
 133                 if (!gfs2_old_multihost_formats[x]) {
 
 135                                "GFS2: code version (%u, %u) is incompatible "
 
 136                                "with ondisk format (%u, %u)\n",
 
 137                                GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
 
 138                                sb->sb_fs_format, sb->sb_multihost_format);
 
 140                                "GFS2: I don't know how to upgrade this FS\n");
 
 145         if (!sdp->sd_args.ar_upgrade) {
 
 147                        "GFS2: code version (%u, %u) is incompatible "
 
 148                        "with ondisk format (%u, %u)\n",
 
 149                        GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
 
 150                        sb->sb_fs_format, sb->sb_multihost_format);
 
 152                        "GFS2: Use the \"upgrade\" mount option to upgrade "
 
 154                 printk(KERN_INFO "GFS2: See the manual for more details\n");
 
 162 static int end_bio_io_page(struct bio *bio, unsigned int bytes_done, int error)
 
 164         struct page *page = bio->bi_private;
 
 169                 SetPageUptodate(page);
 
 171                 printk(KERN_WARNING "gfs2: error %d reading superblock\n", error);
 
 176 static void gfs2_sb_in(struct gfs2_sb_host *sb, const void *buf)
 
 178         const struct gfs2_sb *str = buf;
 
 180         sb->sb_magic = be32_to_cpu(str->sb_header.mh_magic);
 
 181         sb->sb_type = be32_to_cpu(str->sb_header.mh_type);
 
 182         sb->sb_format = be32_to_cpu(str->sb_header.mh_format);
 
 183         sb->sb_fs_format = be32_to_cpu(str->sb_fs_format);
 
 184         sb->sb_multihost_format = be32_to_cpu(str->sb_multihost_format);
 
 185         sb->sb_bsize = be32_to_cpu(str->sb_bsize);
 
 186         sb->sb_bsize_shift = be32_to_cpu(str->sb_bsize_shift);
 
 187         sb->sb_master_dir.no_addr = be64_to_cpu(str->sb_master_dir.no_addr);
 
 188         sb->sb_master_dir.no_formal_ino = be64_to_cpu(str->sb_master_dir.no_formal_ino);
 
 189         sb->sb_root_dir.no_addr = be64_to_cpu(str->sb_root_dir.no_addr);
 
 190         sb->sb_root_dir.no_formal_ino = be64_to_cpu(str->sb_root_dir.no_formal_ino);
 
 192         memcpy(sb->sb_lockproto, str->sb_lockproto, GFS2_LOCKNAME_LEN);
 
 193         memcpy(sb->sb_locktable, str->sb_locktable, GFS2_LOCKNAME_LEN);
 
 197  * gfs2_read_super - Read the gfs2 super block from disk
 
 198  * @sdp: The GFS2 super block
 
 199  * @sector: The location of the super block
 
 200  * @error: The error code to return
 
 202  * This uses the bio functions to read the super block from disk
 
 203  * because we want to be 100% sure that we never read cached data.
 
 204  * A super block is read twice only during each GFS2 mount and is
 
 205  * never written to by the filesystem. The first time its read no
 
 206  * locks are held, and the only details which are looked at are those
 
 207  * relating to the locking protocol. Once locking is up and working,
 
 208  * the sb is read again under the lock to establish the location of
 
 209  * the master directory (contains pointers to journals etc) and the
 
 212  * Returns: 0 on success or error
 
 215 int gfs2_read_super(struct gfs2_sbd *sdp, sector_t sector)
 
 217         struct super_block *sb = sdp->sd_vfs;
 
 222         page = alloc_page(GFP_KERNEL);
 
 226         ClearPageUptodate(page);
 
 227         ClearPageDirty(page);
 
 230         bio = bio_alloc(GFP_KERNEL, 1);
 
 231         if (unlikely(!bio)) {
 
 236         bio->bi_sector = sector * (sb->s_blocksize >> 9);
 
 237         bio->bi_bdev = sb->s_bdev;
 
 238         bio_add_page(bio, page, PAGE_SIZE, 0);
 
 240         bio->bi_end_io = end_bio_io_page;
 
 241         bio->bi_private = page;
 
 242         submit_bio(READ_SYNC | (1 << BIO_RW_META), bio);
 
 243         wait_on_page_locked(page);
 
 245         if (!PageUptodate(page)) {
 
 250         gfs2_sb_in(&sdp->sd_sb, p);
 
 257  * gfs2_read_sb - Read super block
 
 258  * @sdp: The GFS2 superblock
 
 259  * @gl: the glock for the superblock (assumed to be held)
 
 260  * @silent: Don't print message if mount fails
 
 264 int gfs2_read_sb(struct gfs2_sbd *sdp, struct gfs2_glock *gl, int silent)
 
 266         u32 hash_blocks, ind_blocks, leaf_blocks;
 
 271         error = gfs2_read_super(sdp, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift);
 
 274                         fs_err(sdp, "can't read superblock\n");
 
 278         error = gfs2_check_sb(sdp, &sdp->sd_sb, silent);
 
 282         sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
 
 283                                GFS2_BASIC_BLOCK_SHIFT;
 
 284         sdp->sd_fsb2bb = 1 << sdp->sd_fsb2bb_shift;
 
 285         sdp->sd_diptrs = (sdp->sd_sb.sb_bsize -
 
 286                           sizeof(struct gfs2_dinode)) / sizeof(u64);
 
 287         sdp->sd_inptrs = (sdp->sd_sb.sb_bsize -
 
 288                           sizeof(struct gfs2_meta_header)) / sizeof(u64);
 
 289         sdp->sd_jbsize = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header);
 
 290         sdp->sd_hash_bsize = sdp->sd_sb.sb_bsize / 2;
 
 291         sdp->sd_hash_bsize_shift = sdp->sd_sb.sb_bsize_shift - 1;
 
 292         sdp->sd_hash_ptrs = sdp->sd_hash_bsize / sizeof(u64);
 
 293         sdp->sd_qc_per_block = (sdp->sd_sb.sb_bsize -
 
 294                                 sizeof(struct gfs2_meta_header)) /
 
 295                                 sizeof(struct gfs2_quota_change);
 
 297         /* Compute maximum reservation required to add a entry to a directory */
 
 299         hash_blocks = DIV_ROUND_UP(sizeof(u64) * (1 << GFS2_DIR_MAX_DEPTH),
 
 303         for (tmp_blocks = hash_blocks; tmp_blocks > sdp->sd_diptrs;) {
 
 304                 tmp_blocks = DIV_ROUND_UP(tmp_blocks, sdp->sd_inptrs);
 
 305                 ind_blocks += tmp_blocks;
 
 308         leaf_blocks = 2 + GFS2_DIR_MAX_DEPTH;
 
 310         sdp->sd_max_dirres = hash_blocks + ind_blocks + leaf_blocks;
 
 312         sdp->sd_heightsize[0] = sdp->sd_sb.sb_bsize -
 
 313                                 sizeof(struct gfs2_dinode);
 
 314         sdp->sd_heightsize[1] = sdp->sd_sb.sb_bsize * sdp->sd_diptrs;
 
 319                 space = sdp->sd_heightsize[x - 1] * sdp->sd_inptrs;
 
 321                 m = do_div(d, sdp->sd_inptrs);
 
 323                 if (d != sdp->sd_heightsize[x - 1] || m)
 
 325                 sdp->sd_heightsize[x] = space;
 
 327         sdp->sd_max_height = x;
 
 328         gfs2_assert(sdp, sdp->sd_max_height <= GFS2_MAX_META_HEIGHT);
 
 330         sdp->sd_jheightsize[0] = sdp->sd_sb.sb_bsize -
 
 331                                  sizeof(struct gfs2_dinode);
 
 332         sdp->sd_jheightsize[1] = sdp->sd_jbsize * sdp->sd_diptrs;
 
 337                 space = sdp->sd_jheightsize[x - 1] * sdp->sd_inptrs;
 
 339                 m = do_div(d, sdp->sd_inptrs);
 
 341                 if (d != sdp->sd_jheightsize[x - 1] || m)
 
 343                 sdp->sd_jheightsize[x] = space;
 
 345         sdp->sd_max_jheight = x;
 
 346         gfs2_assert(sdp, sdp->sd_max_jheight <= GFS2_MAX_META_HEIGHT);
 
 352  * gfs2_jindex_hold - Grab a lock on the jindex
 
 353  * @sdp: The GFS2 superblock
 
 354  * @ji_gh: the holder for the jindex glock
 
 356  * This is very similar to the gfs2_rindex_hold() function, except that
 
 357  * in general we hold the jindex lock for longer periods of time and
 
 358  * we grab it far less frequently (in general) then the rgrp lock.
 
 363 int gfs2_jindex_hold(struct gfs2_sbd *sdp, struct gfs2_holder *ji_gh)
 
 365         struct gfs2_inode *dip = GFS2_I(sdp->sd_jindex);
 
 368         struct gfs2_jdesc *jd;
 
 373         mutex_lock(&sdp->sd_jindex_mutex);
 
 376                 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, ji_gh);
 
 380                 name.len = sprintf(buf, "journal%u", sdp->sd_journals);
 
 381                 name.hash = gfs2_disk_hash(name.name, name.len);
 
 383                 error = gfs2_dir_check(sdp->sd_jindex, &name, NULL);
 
 384                 if (error == -ENOENT) {
 
 389                 gfs2_glock_dq_uninit(ji_gh);
 
 395                 jd = kzalloc(sizeof(struct gfs2_jdesc), GFP_KERNEL);
 
 399                 jd->jd_inode = gfs2_lookupi(sdp->sd_jindex, &name, 1, NULL);
 
 400                 if (!jd->jd_inode || IS_ERR(jd->jd_inode)) {
 
 404                                 error = PTR_ERR(jd->jd_inode);
 
 409                 spin_lock(&sdp->sd_jindex_spin);
 
 410                 jd->jd_jid = sdp->sd_journals++;
 
 411                 list_add_tail(&jd->jd_list, &sdp->sd_jindex_list);
 
 412                 spin_unlock(&sdp->sd_jindex_spin);
 
 415         mutex_unlock(&sdp->sd_jindex_mutex);
 
 421  * gfs2_jindex_free - Clear all the journal index information
 
 422  * @sdp: The GFS2 superblock
 
 426 void gfs2_jindex_free(struct gfs2_sbd *sdp)
 
 428         struct list_head list;
 
 429         struct gfs2_jdesc *jd;
 
 431         spin_lock(&sdp->sd_jindex_spin);
 
 432         list_add(&list, &sdp->sd_jindex_list);
 
 433         list_del_init(&sdp->sd_jindex_list);
 
 434         sdp->sd_journals = 0;
 
 435         spin_unlock(&sdp->sd_jindex_spin);
 
 437         while (!list_empty(&list)) {
 
 438                 jd = list_entry(list.next, struct gfs2_jdesc, jd_list);
 
 439                 list_del(&jd->jd_list);
 
 445 static struct gfs2_jdesc *jdesc_find_i(struct list_head *head, unsigned int jid)
 
 447         struct gfs2_jdesc *jd;
 
 450         list_for_each_entry(jd, head, jd_list) {
 
 451                 if (jd->jd_jid == jid) {
 
 463 struct gfs2_jdesc *gfs2_jdesc_find(struct gfs2_sbd *sdp, unsigned int jid)
 
 465         struct gfs2_jdesc *jd;
 
 467         spin_lock(&sdp->sd_jindex_spin);
 
 468         jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
 
 469         spin_unlock(&sdp->sd_jindex_spin);
 
 474 void gfs2_jdesc_make_dirty(struct gfs2_sbd *sdp, unsigned int jid)
 
 476         struct gfs2_jdesc *jd;
 
 478         spin_lock(&sdp->sd_jindex_spin);
 
 479         jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
 
 482         spin_unlock(&sdp->sd_jindex_spin);
 
 485 struct gfs2_jdesc *gfs2_jdesc_find_dirty(struct gfs2_sbd *sdp)
 
 487         struct gfs2_jdesc *jd;
 
 490         spin_lock(&sdp->sd_jindex_spin);
 
 492         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 
 499         spin_unlock(&sdp->sd_jindex_spin);
 
 507 int gfs2_jdesc_check(struct gfs2_jdesc *jd)
 
 509         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
 
 510         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 
 514         if (ip->i_di.di_size < (8 << 20) || ip->i_di.di_size > (1 << 30) ||
 
 515             (ip->i_di.di_size & (sdp->sd_sb.sb_bsize - 1))) {
 
 516                 gfs2_consist_inode(ip);
 
 519         jd->jd_blocks = ip->i_di.di_size >> sdp->sd_sb.sb_bsize_shift;
 
 521         error = gfs2_write_alloc_required(ip, 0, ip->i_di.di_size, &ar);
 
 523                 gfs2_consist_inode(ip);
 
 531  * gfs2_make_fs_rw - Turn a Read-Only FS into a Read-Write one
 
 532  * @sdp: the filesystem
 
 537 int gfs2_make_fs_rw(struct gfs2_sbd *sdp)
 
 539         struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
 
 540         struct gfs2_glock *j_gl = ip->i_gl;
 
 541         struct gfs2_holder t_gh;
 
 542         struct gfs2_log_header_host head;
 
 545         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED, 0, &t_gh);
 
 549         gfs2_meta_cache_flush(ip);
 
 550         j_gl->gl_ops->go_inval(j_gl, DIO_METADATA);
 
 552         error = gfs2_find_jhead(sdp->sd_jdesc, &head);
 
 556         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 
 562         /*  Initialize some head of the log stuff  */
 
 563         sdp->sd_log_sequence = head.lh_sequence + 1;
 
 564         gfs2_log_pointers_init(sdp, head.lh_blkno);
 
 566         error = gfs2_quota_init(sdp);
 
 570         set_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 
 572         gfs2_glock_dq_uninit(&t_gh);
 
 577         t_gh.gh_flags |= GL_NOCACHE;
 
 578         gfs2_glock_dq_uninit(&t_gh);
 
 584  * gfs2_make_fs_ro - Turn a Read-Write FS into a Read-Only one
 
 585  * @sdp: the filesystem
 
 590 int gfs2_make_fs_ro(struct gfs2_sbd *sdp)
 
 592         struct gfs2_holder t_gh;
 
 595         gfs2_quota_sync(sdp);
 
 596         gfs2_statfs_sync(sdp);
 
 598         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED, GL_NOCACHE,
 
 600         if (error && !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
 
 603         gfs2_meta_syncfs(sdp);
 
 604         gfs2_log_shutdown(sdp);
 
 606         clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 
 609                 gfs2_glock_dq_uninit(&t_gh);
 
 611         gfs2_quota_cleanup(sdp);
 
 616 static void gfs2_statfs_change_in(struct gfs2_statfs_change_host *sc, const void *buf)
 
 618         const struct gfs2_statfs_change *str = buf;
 
 620         sc->sc_total = be64_to_cpu(str->sc_total);
 
 621         sc->sc_free = be64_to_cpu(str->sc_free);
 
 622         sc->sc_dinodes = be64_to_cpu(str->sc_dinodes);
 
 625 static void gfs2_statfs_change_out(const struct gfs2_statfs_change_host *sc, void *buf)
 
 627         struct gfs2_statfs_change *str = buf;
 
 629         str->sc_total = cpu_to_be64(sc->sc_total);
 
 630         str->sc_free = cpu_to_be64(sc->sc_free);
 
 631         str->sc_dinodes = cpu_to_be64(sc->sc_dinodes);
 
 634 int gfs2_statfs_init(struct gfs2_sbd *sdp)
 
 636         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 
 637         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 
 638         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 
 639         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 
 640         struct buffer_head *m_bh, *l_bh;
 
 641         struct gfs2_holder gh;
 
 644         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 
 649         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 
 653         if (sdp->sd_args.ar_spectator) {
 
 654                 spin_lock(&sdp->sd_statfs_spin);
 
 655                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 
 656                                       sizeof(struct gfs2_dinode));
 
 657                 spin_unlock(&sdp->sd_statfs_spin);
 
 659                 error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 
 663                 spin_lock(&sdp->sd_statfs_spin);
 
 664                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 
 665                                       sizeof(struct gfs2_dinode));
 
 666                 gfs2_statfs_change_in(l_sc, l_bh->b_data +
 
 667                                       sizeof(struct gfs2_dinode));
 
 668                 spin_unlock(&sdp->sd_statfs_spin);
 
 676         gfs2_glock_dq_uninit(&gh);
 
 680 void gfs2_statfs_change(struct gfs2_sbd *sdp, s64 total, s64 free,
 
 683         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 
 684         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 
 685         struct buffer_head *l_bh;
 
 688         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 
 692         mutex_lock(&sdp->sd_statfs_mutex);
 
 693         gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
 
 694         mutex_unlock(&sdp->sd_statfs_mutex);
 
 696         spin_lock(&sdp->sd_statfs_spin);
 
 697         l_sc->sc_total += total;
 
 698         l_sc->sc_free += free;
 
 699         l_sc->sc_dinodes += dinodes;
 
 700         gfs2_statfs_change_out(l_sc, l_bh->b_data + sizeof(struct gfs2_dinode));
 
 701         spin_unlock(&sdp->sd_statfs_spin);
 
 706 int gfs2_statfs_sync(struct gfs2_sbd *sdp)
 
 708         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 
 709         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 
 710         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 
 711         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 
 712         struct gfs2_holder gh;
 
 713         struct buffer_head *m_bh, *l_bh;
 
 716         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 
 721         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 
 725         spin_lock(&sdp->sd_statfs_spin);
 
 726         gfs2_statfs_change_in(m_sc, m_bh->b_data +
 
 727                               sizeof(struct gfs2_dinode));
 
 728         if (!l_sc->sc_total && !l_sc->sc_free && !l_sc->sc_dinodes) {
 
 729                 spin_unlock(&sdp->sd_statfs_spin);
 
 732         spin_unlock(&sdp->sd_statfs_spin);
 
 734         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 
 738         error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
 
 742         mutex_lock(&sdp->sd_statfs_mutex);
 
 743         gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
 
 744         mutex_unlock(&sdp->sd_statfs_mutex);
 
 746         spin_lock(&sdp->sd_statfs_spin);
 
 747         m_sc->sc_total += l_sc->sc_total;
 
 748         m_sc->sc_free += l_sc->sc_free;
 
 749         m_sc->sc_dinodes += l_sc->sc_dinodes;
 
 750         memset(l_sc, 0, sizeof(struct gfs2_statfs_change));
 
 751         memset(l_bh->b_data + sizeof(struct gfs2_dinode),
 
 752                0, sizeof(struct gfs2_statfs_change));
 
 753         spin_unlock(&sdp->sd_statfs_spin);
 
 755         gfs2_trans_add_bh(m_ip->i_gl, m_bh, 1);
 
 756         gfs2_statfs_change_out(m_sc, m_bh->b_data + sizeof(struct gfs2_dinode));
 
 765         gfs2_glock_dq_uninit(&gh);
 
 770  * gfs2_statfs_i - Do a statfs
 
 771  * @sdp: the filesystem
 
 772  * @sg: the sg structure
 
 777 int gfs2_statfs_i(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
 
 779         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 
 780         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 
 782         spin_lock(&sdp->sd_statfs_spin);
 
 785         sc->sc_total += l_sc->sc_total;
 
 786         sc->sc_free += l_sc->sc_free;
 
 787         sc->sc_dinodes += l_sc->sc_dinodes;
 
 789         spin_unlock(&sdp->sd_statfs_spin);
 
 793         if (sc->sc_free > sc->sc_total)
 
 794                 sc->sc_free = sc->sc_total;
 
 795         if (sc->sc_dinodes < 0)
 
 802  * statfs_fill - fill in the sg for a given RG
 
 804  * @sc: the sc structure
 
 806  * Returns: 0 on success, -ESTALE if the LVB is invalid
 
 809 static int statfs_slow_fill(struct gfs2_rgrpd *rgd,
 
 810                             struct gfs2_statfs_change_host *sc)
 
 812         gfs2_rgrp_verify(rgd);
 
 813         sc->sc_total += rgd->rd_data;
 
 814         sc->sc_free += rgd->rd_rg.rg_free;
 
 815         sc->sc_dinodes += rgd->rd_rg.rg_dinodes;
 
 820  * gfs2_statfs_slow - Stat a filesystem using asynchronous locking
 
 821  * @sdp: the filesystem
 
 822  * @sc: the sc info that will be returned
 
 824  * Any error (other than a signal) will cause this routine to fall back
 
 825  * to the synchronous version.
 
 827  * FIXME: This really shouldn't busy wait like this.
 
 832 int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
 
 834         struct gfs2_holder ri_gh;
 
 835         struct gfs2_rgrpd *rgd_next;
 
 836         struct gfs2_holder *gha, *gh;
 
 837         unsigned int slots = 64;
 
 842         memset(sc, 0, sizeof(struct gfs2_statfs_change_host));
 
 843         gha = kcalloc(slots, sizeof(struct gfs2_holder), GFP_KERNEL);
 
 847         error = gfs2_rindex_hold(sdp, &ri_gh);
 
 851         rgd_next = gfs2_rgrpd_get_first(sdp);
 
 856                 for (x = 0; x < slots; x++) {
 
 859                         if (gh->gh_gl && gfs2_glock_poll(gh)) {
 
 860                                 err = gfs2_glock_wait(gh);
 
 862                                         gfs2_holder_uninit(gh);
 
 866                                                 error = statfs_slow_fill(
 
 867                                                         gh->gh_gl->gl_object, sc);
 
 868                                         gfs2_glock_dq_uninit(gh);
 
 874                         else if (rgd_next && !error) {
 
 875                                 error = gfs2_glock_nq_init(rgd_next->rd_gl,
 
 879                                 rgd_next = gfs2_rgrpd_get_next(rgd_next);
 
 883                         if (signal_pending(current))
 
 884                                 error = -ERESTARTSYS;
 
 893         gfs2_glock_dq_uninit(&ri_gh);
 
 901         struct list_head list;
 
 902         struct gfs2_holder gh;
 
 906  * gfs2_lock_fs_check_clean - Stop all writes to the FS and check that all
 
 908  * @sdp: the file system
 
 909  * @state: the state to put the transaction lock into
 
 910  * @t_gh: the hold on the transaction lock
 
 915 static int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp,
 
 916                                     struct gfs2_holder *t_gh)
 
 918         struct gfs2_inode *ip;
 
 919         struct gfs2_holder ji_gh;
 
 920         struct gfs2_jdesc *jd;
 
 923         struct gfs2_log_header_host lh;
 
 926         error = gfs2_jindex_hold(sdp, &ji_gh);
 
 930         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 
 931                 lfcc = kmalloc(sizeof(struct lfcc), GFP_KERNEL);
 
 936                 ip = GFS2_I(jd->jd_inode);
 
 937                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &lfcc->gh);
 
 942                 list_add(&lfcc->list, &list);
 
 945         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_DEFERRED,
 
 946                                LM_FLAG_PRIORITY | GL_NOCACHE,
 
 949         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 
 950                 error = gfs2_jdesc_check(jd);
 
 953                 error = gfs2_find_jhead(jd, &lh);
 
 956                 if (!(lh.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 
 963                 gfs2_glock_dq_uninit(t_gh);
 
 966         while (!list_empty(&list)) {
 
 967                 lfcc = list_entry(list.next, struct lfcc, list);
 
 968                 list_del(&lfcc->list);
 
 969                 gfs2_glock_dq_uninit(&lfcc->gh);
 
 972         gfs2_glock_dq_uninit(&ji_gh);
 
 977  * gfs2_freeze_fs - freezes the file system
 
 978  * @sdp: the file system
 
 980  * This function flushes data and meta data for all machines by
 
 981  * aquiring the transaction log exclusively.  All journals are
 
 982  * ensured to be in a clean state as well.
 
 987 int gfs2_freeze_fs(struct gfs2_sbd *sdp)
 
 991         mutex_lock(&sdp->sd_freeze_lock);
 
 993         if (!sdp->sd_freeze_count++) {
 
 994                 error = gfs2_lock_fs_check_clean(sdp, &sdp->sd_freeze_gh);
 
 996                         sdp->sd_freeze_count--;
 
 999         mutex_unlock(&sdp->sd_freeze_lock);
 
1005  * gfs2_unfreeze_fs - unfreezes the file system
 
1006  * @sdp: the file system
 
1008  * This function allows the file system to proceed by unlocking
 
1009  * the exclusively held transaction lock.  Other GFS2 nodes are
 
1010  * now free to acquire the lock shared and go on with their lives.
 
1014 void gfs2_unfreeze_fs(struct gfs2_sbd *sdp)
 
1016         mutex_lock(&sdp->sd_freeze_lock);
 
1018         if (sdp->sd_freeze_count && !--sdp->sd_freeze_count)
 
1019                 gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
 
1021         mutex_unlock(&sdp->sd_freeze_lock);