git.oblomov.eu Git - linux-2.6/blob - fs/gfs2/super.c

   1 /*
   2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3  * Copyright (C) 2004-2007 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_demote_secs = 300;
  55         gt->gt_incore_log_blocks = 1024;
  56         gt->gt_log_flush_secs = 60;
  57         gt->gt_recoverd_secs = 60;
  58         gt->gt_logd_secs = 1;
  59         gt->gt_quotad_secs = 5;
  60         gt->gt_quota_simul_sync = 64;
  61         gt->gt_quota_warn_period = 10;
  62         gt->gt_quota_scale_num = 1;
  63         gt->gt_quota_scale_den = 1;
  64         gt->gt_quota_cache_secs = 300;
  65         gt->gt_quota_quantum = 60;
  66         gt->gt_atime_quantum = 3600;
  67         gt->gt_new_files_jdata = 0;
  68         gt->gt_max_readahead = 1 << 18;
  69         gt->gt_stall_secs = 600;
  70         gt->gt_complain_secs = 10;
  71         gt->gt_statfs_quantum = 30;
  72         gt->gt_statfs_slow = 0;
  73 }
  74
  75 /**
  76  * gfs2_check_sb - Check superblock
  77  * @sdp: the filesystem
  78  * @sb: The superblock
  79  * @silent: Don't print a message if the check fails
  80  *
  81  * Checks the version code of the FS is one that we understand how to
  82  * read and that the sizes of the various on-disk structures have not
  83  * changed.
  84  */
  85
  86 int gfs2_check_sb(struct gfs2_sbd *sdp, struct gfs2_sb_host *sb, int silent)
  87 {
  88         unsigned int x;
  89
  90         if (sb->sb_magic != GFS2_MAGIC ||
  91             sb->sb_type != GFS2_METATYPE_SB) {
  92                 if (!silent)
  93                         printk(KERN_WARNING "GFS2: not a GFS2 filesystem\n");
  94                 return -EINVAL;
  95         }
  96
  97         /*  If format numbers match exactly, we're done.  */
  98
  99         if (sb->sb_fs_format == GFS2_FORMAT_FS &&
 100             sb->sb_multihost_format == GFS2_FORMAT_MULTI)
 101                 return 0;
 102
 103         if (sb->sb_fs_format != GFS2_FORMAT_FS) {
 104                 for (x = 0; gfs2_old_fs_formats[x]; x++)
 105                         if (gfs2_old_fs_formats[x] == sb->sb_fs_format)
 106                                 break;
 107
 108                 if (!gfs2_old_fs_formats[x]) {
 109                         printk(KERN_WARNING
 110                                "GFS2: code version (%u, %u) is incompatible "
 111                                "with ondisk format (%u, %u)\n",
 112                                GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
 113                                sb->sb_fs_format, sb->sb_multihost_format);
 114                         printk(KERN_WARNING
 115                                "GFS2: I don't know how to upgrade this FS\n");
 116                         return -EINVAL;
 117                 }
 118         }
 119
 120         if (sb->sb_multihost_format != GFS2_FORMAT_MULTI) {
 121                 for (x = 0; gfs2_old_multihost_formats[x]; x++)
 122                         if (gfs2_old_multihost_formats[x] ==
 123                             sb->sb_multihost_format)
 124                                 break;
 125
 126                 if (!gfs2_old_multihost_formats[x]) {
 127                         printk(KERN_WARNING
 128                                "GFS2: code version (%u, %u) is incompatible "
 129                                "with ondisk format (%u, %u)\n",
 130                                GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
 131                                sb->sb_fs_format, sb->sb_multihost_format);
 132                         printk(KERN_WARNING
 133                                "GFS2: I don't know how to upgrade this FS\n");
 134                         return -EINVAL;
 135                 }
 136         }
 137
 138         if (!sdp->sd_args.ar_upgrade) {
 139                 printk(KERN_WARNING
 140                        "GFS2: code version (%u, %u) is incompatible "
 141                        "with ondisk format (%u, %u)\n",
 142                        GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
 143                        sb->sb_fs_format, sb->sb_multihost_format);
 144                 printk(KERN_INFO
 145                        "GFS2: Use the \"upgrade\" mount option to upgrade "
 146                        "the FS\n");
 147                 printk(KERN_INFO "GFS2: See the manual for more details\n");
 148                 return -EINVAL;
 149         }
 150
 151         return 0;
 152 }
 153
 154
 155 static void end_bio_io_page(struct bio *bio, int error)
 156 {
 157         struct page *page = bio->bi_private;
 158
 159         if (!error)
 160                 SetPageUptodate(page);
 161         else
 162                 printk(KERN_WARNING "gfs2: error %d reading superblock\n", error);
 163         unlock_page(page);
 164 }
 165
 166 static void gfs2_sb_in(struct gfs2_sb_host *sb, const void *buf)
 167 {
 168         const struct gfs2_sb *str = buf;
 169
 170         sb->sb_magic = be32_to_cpu(str->sb_header.mh_magic);
 171         sb->sb_type = be32_to_cpu(str->sb_header.mh_type);
 172         sb->sb_format = be32_to_cpu(str->sb_header.mh_format);
 173         sb->sb_fs_format = be32_to_cpu(str->sb_fs_format);
 174         sb->sb_multihost_format = be32_to_cpu(str->sb_multihost_format);
 175         sb->sb_bsize = be32_to_cpu(str->sb_bsize);
 176         sb->sb_bsize_shift = be32_to_cpu(str->sb_bsize_shift);
 177         sb->sb_master_dir.no_addr = be64_to_cpu(str->sb_master_dir.no_addr);
 178         sb->sb_master_dir.no_formal_ino = be64_to_cpu(str->sb_master_dir.no_formal_ino);
 179         sb->sb_root_dir.no_addr = be64_to_cpu(str->sb_root_dir.no_addr);
 180         sb->sb_root_dir.no_formal_ino = be64_to_cpu(str->sb_root_dir.no_formal_ino);
 181
 182         memcpy(sb->sb_lockproto, str->sb_lockproto, GFS2_LOCKNAME_LEN);
 183         memcpy(sb->sb_locktable, str->sb_locktable, GFS2_LOCKNAME_LEN);
 184 }
 185
 186 /**
 187  * gfs2_read_super - Read the gfs2 super block from disk
 188  * @sdp: The GFS2 super block
 189  * @sector: The location of the super block
 190  * @error: The error code to return
 191  *
 192  * This uses the bio functions to read the super block from disk
 193  * because we want to be 100% sure that we never read cached data.
 194  * A super block is read twice only during each GFS2 mount and is
 195  * never written to by the filesystem. The first time its read no
 196  * locks are held, and the only details which are looked at are those
 197  * relating to the locking protocol. Once locking is up and working,
 198  * the sb is read again under the lock to establish the location of
 199  * the master directory (contains pointers to journals etc) and the
 200  * root directory.
 201  *
 202  * Returns: 0 on success or error
 203  */
 204
 205 int gfs2_read_super(struct gfs2_sbd *sdp, sector_t sector)
 206 {
 207         struct super_block *sb = sdp->sd_vfs;
 208         struct gfs2_sb *p;
 209         struct page *page;
 210         struct bio *bio;
 211
 212         page = alloc_page(GFP_NOFS);
 213         if (unlikely(!page))
 214                 return -ENOBUFS;
 215
 216         ClearPageUptodate(page);
 217         ClearPageDirty(page);
 218         lock_page(page);
 219
 220         bio = bio_alloc(GFP_NOFS, 1);
 221         if (unlikely(!bio)) {
 222                 __free_page(page);
 223                 return -ENOBUFS;
 224         }
 225
 226         bio->bi_sector = sector * (sb->s_blocksize >> 9);
 227         bio->bi_bdev = sb->s_bdev;
 228         bio_add_page(bio, page, PAGE_SIZE, 0);
 229
 230         bio->bi_end_io = end_bio_io_page;
 231         bio->bi_private = page;
 232         submit_bio(READ_SYNC | (1 << BIO_RW_META), bio);
 233         wait_on_page_locked(page);
 234         bio_put(bio);
 235         if (!PageUptodate(page)) {
 236                 __free_page(page);
 237                 return -EIO;
 238         }
 239         p = kmap(page);
 240         gfs2_sb_in(&sdp->sd_sb, p);
 241         kunmap(page);
 242         __free_page(page);
 243         return 0;
 244 }
 245
 246 /**
 247  * gfs2_read_sb - Read super block
 248  * @sdp: The GFS2 superblock
 249  * @gl: the glock for the superblock (assumed to be held)
 250  * @silent: Don't print message if mount fails
 251  *
 252  */
 253
 254 int gfs2_read_sb(struct gfs2_sbd *sdp, struct gfs2_glock *gl, int silent)
 255 {
 256         u32 hash_blocks, ind_blocks, leaf_blocks;
 257         u32 tmp_blocks;
 258         unsigned int x;
 259         int error;
 260
 261         error = gfs2_read_super(sdp, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift);
 262         if (error) {
 263                 if (!silent)
 264                         fs_err(sdp, "can't read superblock\n");
 265                 return error;
 266         }
 267
 268         error = gfs2_check_sb(sdp, &sdp->sd_sb, silent);
 269         if (error)
 270                 return error;
 271
 272         sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
 273                                GFS2_BASIC_BLOCK_SHIFT;
 274         sdp->sd_fsb2bb = 1 << sdp->sd_fsb2bb_shift;
 275         sdp->sd_diptrs = (sdp->sd_sb.sb_bsize -
 276                           sizeof(struct gfs2_dinode)) / sizeof(u64);
 277         sdp->sd_inptrs = (sdp->sd_sb.sb_bsize -
 278                           sizeof(struct gfs2_meta_header)) / sizeof(u64);
 279         sdp->sd_jbsize = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header);
 280         sdp->sd_hash_bsize = sdp->sd_sb.sb_bsize / 2;
 281         sdp->sd_hash_bsize_shift = sdp->sd_sb.sb_bsize_shift - 1;
 282         sdp->sd_hash_ptrs = sdp->sd_hash_bsize / sizeof(u64);
 283         sdp->sd_qc_per_block = (sdp->sd_sb.sb_bsize -
 284                                 sizeof(struct gfs2_meta_header)) /
 285                                 sizeof(struct gfs2_quota_change);
 286
 287         /* Compute maximum reservation required to add a entry to a directory */
 288
 289         hash_blocks = DIV_ROUND_UP(sizeof(u64) * (1 << GFS2_DIR_MAX_DEPTH),
 290                              sdp->sd_jbsize);
 291
 292         ind_blocks = 0;
 293         for (tmp_blocks = hash_blocks; tmp_blocks > sdp->sd_diptrs;) {
 294                 tmp_blocks = DIV_ROUND_UP(tmp_blocks, sdp->sd_inptrs);
 295                 ind_blocks += tmp_blocks;
 296         }
 297
 298         leaf_blocks = 2 + GFS2_DIR_MAX_DEPTH;
 299
 300         sdp->sd_max_dirres = hash_blocks + ind_blocks + leaf_blocks;
 301
 302         sdp->sd_heightsize[0] = sdp->sd_sb.sb_bsize -
 303                                 sizeof(struct gfs2_dinode);
 304         sdp->sd_heightsize[1] = sdp->sd_sb.sb_bsize * sdp->sd_diptrs;
 305         for (x = 2;; x++) {
 306                 u64 space, d;
 307                 u32 m;
 308
 309                 space = sdp->sd_heightsize[x - 1] * sdp->sd_inptrs;
 310                 d = space;
 311                 m = do_div(d, sdp->sd_inptrs);
 312
 313                 if (d != sdp->sd_heightsize[x - 1] || m)
 314                         break;
 315                 sdp->sd_heightsize[x] = space;
 316         }
 317         sdp->sd_max_height = x;
 318         sdp->sd_heightsize[x] = ~0;
 319         gfs2_assert(sdp, sdp->sd_max_height <= GFS2_MAX_META_HEIGHT);
 320
 321         sdp->sd_jheightsize[0] = sdp->sd_sb.sb_bsize -
 322                                  sizeof(struct gfs2_dinode);
 323         sdp->sd_jheightsize[1] = sdp->sd_jbsize * sdp->sd_diptrs;
 324         for (x = 2;; x++) {
 325                 u64 space, d;
 326                 u32 m;
 327
 328                 space = sdp->sd_jheightsize[x - 1] * sdp->sd_inptrs;
 329                 d = space;
 330                 m = do_div(d, sdp->sd_inptrs);
 331
 332                 if (d != sdp->sd_jheightsize[x - 1] || m)
 333                         break;
 334                 sdp->sd_jheightsize[x] = space;
 335         }
 336         sdp->sd_max_jheight = x;
 337         sdp->sd_jheightsize[x] = ~0;
 338         gfs2_assert(sdp, sdp->sd_max_jheight <= GFS2_MAX_META_HEIGHT);
 339
 340         return 0;
 341 }
 342
 343 /**
 344  * gfs2_jindex_hold - Grab a lock on the jindex
 345  * @sdp: The GFS2 superblock
 346  * @ji_gh: the holder for the jindex glock
 347  *
 348  * This is very similar to the gfs2_rindex_hold() function, except that
 349  * in general we hold the jindex lock for longer periods of time and
 350  * we grab it far less frequently (in general) then the rgrp lock.
 351  *
 352  * Returns: errno
 353  */
 354
 355 int gfs2_jindex_hold(struct gfs2_sbd *sdp, struct gfs2_holder *ji_gh)
 356 {
 357         struct gfs2_inode *dip = GFS2_I(sdp->sd_jindex);
 358         struct qstr name;
 359         char buf[20];
 360         struct gfs2_jdesc *jd;
 361         int error;
 362
 363         name.name = buf;
 364
 365         mutex_lock(&sdp->sd_jindex_mutex);
 366
 367         for (;;) {
 368                 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, ji_gh);
 369                 if (error)
 370                         break;
 371
 372                 name.len = sprintf(buf, "journal%u", sdp->sd_journals);
 373                 name.hash = gfs2_disk_hash(name.name, name.len);
 374
 375                 error = gfs2_dir_check(sdp->sd_jindex, &name, NULL);
 376                 if (error == -ENOENT) {
 377                         error = 0;
 378                         break;
 379                 }
 380
 381                 gfs2_glock_dq_uninit(ji_gh);
 382
 383                 if (error)
 384                         break;
 385
 386                 error = -ENOMEM;
 387                 jd = kzalloc(sizeof(struct gfs2_jdesc), GFP_KERNEL);
 388                 if (!jd)
 389                         break;
 390
 391                 INIT_LIST_HEAD(&jd->extent_list);
 392                 jd->jd_inode = gfs2_lookupi(sdp->sd_jindex, &name, 1, NULL);
 393                 if (!jd->jd_inode || IS_ERR(jd->jd_inode)) {
 394                         if (!jd->jd_inode)
 395                                 error = -ENOENT;
 396                         else
 397                                 error = PTR_ERR(jd->jd_inode);
 398                         kfree(jd);
 399                         break;
 400                 }
 401
 402                 spin_lock(&sdp->sd_jindex_spin);
 403                 jd->jd_jid = sdp->sd_journals++;
 404                 list_add_tail(&jd->jd_list, &sdp->sd_jindex_list);
 405                 spin_unlock(&sdp->sd_jindex_spin);
 406         }
 407
 408         mutex_unlock(&sdp->sd_jindex_mutex);
 409
 410         return error;
 411 }
 412
 413 /**
 414  * gfs2_jindex_free - Clear all the journal index information
 415  * @sdp: The GFS2 superblock
 416  *
 417  */
 418
 419 void gfs2_jindex_free(struct gfs2_sbd *sdp)
 420 {
 421         struct list_head list, *head;
 422         struct gfs2_jdesc *jd;
 423         struct gfs2_journal_extent *jext;
 424
 425         spin_lock(&sdp->sd_jindex_spin);
 426         list_add(&list, &sdp->sd_jindex_list);
 427         list_del_init(&sdp->sd_jindex_list);
 428         sdp->sd_journals = 0;
 429         spin_unlock(&sdp->sd_jindex_spin);
 430
 431         while (!list_empty(&list)) {
 432                 jd = list_entry(list.next, struct gfs2_jdesc, jd_list);
 433                 head = &jd->extent_list;
 434                 while (!list_empty(head)) {
 435                         jext = list_entry(head->next,
 436                                           struct gfs2_journal_extent,
 437                                           extent_list);
 438                         list_del(&jext->extent_list);
 439                         kfree(jext);
 440                 }
 441                 list_del(&jd->jd_list);
 442                 iput(jd->jd_inode);
 443                 kfree(jd);
 444         }
 445 }
 446
 447 static struct gfs2_jdesc *jdesc_find_i(struct list_head *head, unsigned int jid)
 448 {
 449         struct gfs2_jdesc *jd;
 450         int found = 0;
 451
 452         list_for_each_entry(jd, head, jd_list) {
 453                 if (jd->jd_jid == jid) {
 454                         found = 1;
 455                         break;
 456                 }
 457         }
 458
 459         if (!found)
 460                 jd = NULL;
 461
 462         return jd;
 463 }
 464
 465 struct gfs2_jdesc *gfs2_jdesc_find(struct gfs2_sbd *sdp, unsigned int jid)
 466 {
 467         struct gfs2_jdesc *jd;
 468
 469         spin_lock(&sdp->sd_jindex_spin);
 470         jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
 471         spin_unlock(&sdp->sd_jindex_spin);
 472
 473         return jd;
 474 }
 475
 476 void gfs2_jdesc_make_dirty(struct gfs2_sbd *sdp, unsigned int jid)
 477 {
 478         struct gfs2_jdesc *jd;
 479
 480         spin_lock(&sdp->sd_jindex_spin);
 481         jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
 482         if (jd)
 483                 jd->jd_dirty = 1;
 484         spin_unlock(&sdp->sd_jindex_spin);
 485 }
 486
 487 struct gfs2_jdesc *gfs2_jdesc_find_dirty(struct gfs2_sbd *sdp)
 488 {
 489         struct gfs2_jdesc *jd;
 490         int found = 0;
 491
 492         spin_lock(&sdp->sd_jindex_spin);
 493
 494         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 495                 if (jd->jd_dirty) {
 496                         jd->jd_dirty = 0;
 497                         found = 1;
 498                         break;
 499                 }
 500         }
 501         spin_unlock(&sdp->sd_jindex_spin);
 502
 503         if (!found)
 504                 jd = NULL;
 505
 506         return jd;
 507 }
 508
 509 int gfs2_jdesc_check(struct gfs2_jdesc *jd)
 510 {
 511         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
 512         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 513         int ar;
 514         int error;
 515
 516         if (ip->i_di.di_size < (8 << 20) || ip->i_di.di_size > (1 << 30) ||
 517             (ip->i_di.di_size & (sdp->sd_sb.sb_bsize - 1))) {
 518                 gfs2_consist_inode(ip);
 519                 return -EIO;
 520         }
 521         jd->jd_blocks = ip->i_di.di_size >> sdp->sd_sb.sb_bsize_shift;
 522
 523         error = gfs2_write_alloc_required(ip, 0, ip->i_di.di_size, &ar);
 524         if (!error && ar) {
 525                 gfs2_consist_inode(ip);
 526                 error = -EIO;
 527         }
 528
 529         return error;
 530 }
 531
 532 /**
 533  * gfs2_make_fs_rw - Turn a Read-Only FS into a Read-Write one
 534  * @sdp: the filesystem
 535  *
 536  * Returns: errno
 537  */
 538
 539 int gfs2_make_fs_rw(struct gfs2_sbd *sdp)
 540 {
 541         struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
 542         struct gfs2_glock *j_gl = ip->i_gl;
 543         struct gfs2_holder t_gh;
 544         struct gfs2_log_header_host head;
 545         int error;
 546
 547         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED, 0, &t_gh);
 548         if (error)
 549                 return error;
 550
 551         j_gl->gl_ops->go_inval(j_gl, DIO_METADATA);
 552
 553         error = gfs2_find_jhead(sdp->sd_jdesc, &head);
 554         if (error)
 555                 goto fail;
 556
 557         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 558                 gfs2_consist(sdp);
 559                 error = -EIO;
 560                 goto fail;
 561         }
 562
 563         /*  Initialize some head of the log stuff  */
 564         sdp->sd_log_sequence = head.lh_sequence + 1;
 565         gfs2_log_pointers_init(sdp, head.lh_blkno);
 566
 567         error = gfs2_quota_init(sdp);
 568         if (error)
 569                 goto fail;
 570
 571         set_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 572
 573         gfs2_glock_dq_uninit(&t_gh);
 574
 575         return 0;
 576
 577 fail:
 578         t_gh.gh_flags |= GL_NOCACHE;
 579         gfs2_glock_dq_uninit(&t_gh);
 580
 581         return error;
 582 }
 583
 584 /**
 585  * gfs2_make_fs_ro - Turn a Read-Write FS into a Read-Only one
 586  * @sdp: the filesystem
 587  *
 588  * Returns: errno
 589  */
 590
 591 int gfs2_make_fs_ro(struct gfs2_sbd *sdp)
 592 {
 593         struct gfs2_holder t_gh;
 594         int error;
 595
 596         gfs2_quota_sync(sdp);
 597         gfs2_statfs_sync(sdp);
 598
 599         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED, GL_NOCACHE,
 600                                    &t_gh);
 601         if (error && !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
 602                 return error;
 603
 604         gfs2_meta_syncfs(sdp);
 605         gfs2_log_shutdown(sdp);
 606
 607         clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 608
 609         if (t_gh.gh_gl)
 610                 gfs2_glock_dq_uninit(&t_gh);
 611
 612         gfs2_quota_cleanup(sdp);
 613
 614         return error;
 615 }
 616
 617 static void gfs2_statfs_change_in(struct gfs2_statfs_change_host *sc, const void *buf)
 618 {
 619         const struct gfs2_statfs_change *str = buf;
 620
 621         sc->sc_total = be64_to_cpu(str->sc_total);
 622         sc->sc_free = be64_to_cpu(str->sc_free);
 623         sc->sc_dinodes = be64_to_cpu(str->sc_dinodes);
 624 }
 625
 626 static void gfs2_statfs_change_out(const struct gfs2_statfs_change_host *sc, void *buf)
 627 {
 628         struct gfs2_statfs_change *str = buf;
 629
 630         str->sc_total = cpu_to_be64(sc->sc_total);
 631         str->sc_free = cpu_to_be64(sc->sc_free);
 632         str->sc_dinodes = cpu_to_be64(sc->sc_dinodes);
 633 }
 634
 635 int gfs2_statfs_init(struct gfs2_sbd *sdp)
 636 {
 637         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 638         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 639         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 640         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 641         struct buffer_head *m_bh, *l_bh;
 642         struct gfs2_holder gh;
 643         int error;
 644
 645         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 646                                    &gh);
 647         if (error)
 648                 return error;
 649
 650         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 651         if (error)
 652                 goto out;
 653
 654         if (sdp->sd_args.ar_spectator) {
 655                 spin_lock(&sdp->sd_statfs_spin);
 656                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 657                                       sizeof(struct gfs2_dinode));
 658                 spin_unlock(&sdp->sd_statfs_spin);
 659         } else {
 660                 error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 661                 if (error)
 662                         goto out_m_bh;
 663
 664                 spin_lock(&sdp->sd_statfs_spin);
 665                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 666                                       sizeof(struct gfs2_dinode));
 667                 gfs2_statfs_change_in(l_sc, l_bh->b_data +
 668                                       sizeof(struct gfs2_dinode));
 669                 spin_unlock(&sdp->sd_statfs_spin);
 670
 671                 brelse(l_bh);
 672         }
 673
 674 out_m_bh:
 675         brelse(m_bh);
 676 out:
 677         gfs2_glock_dq_uninit(&gh);
 678         return 0;
 679 }
 680
 681 void gfs2_statfs_change(struct gfs2_sbd *sdp, s64 total, s64 free,
 682                         s64 dinodes)
 683 {
 684         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 685         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 686         struct buffer_head *l_bh;
 687         int error;
 688
 689         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 690         if (error)
 691                 return;
 692
 693         gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
 694
 695         spin_lock(&sdp->sd_statfs_spin);
 696         l_sc->sc_total += total;
 697         l_sc->sc_free += free;
 698         l_sc->sc_dinodes += dinodes;
 699         gfs2_statfs_change_out(l_sc, l_bh->b_data + sizeof(struct gfs2_dinode));
 700         spin_unlock(&sdp->sd_statfs_spin);
 701
 702         brelse(l_bh);
 703 }
 704
 705 int gfs2_statfs_sync(struct gfs2_sbd *sdp)
 706 {
 707         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 708         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 709         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 710         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 711         struct gfs2_holder gh;
 712         struct buffer_head *m_bh, *l_bh;
 713         int error;
 714
 715         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 716                                    &gh);
 717         if (error)
 718                 return error;
 719
 720         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 721         if (error)
 722                 goto out;
 723
 724         spin_lock(&sdp->sd_statfs_spin);
 725         gfs2_statfs_change_in(m_sc, m_bh->b_data +
 726                               sizeof(struct gfs2_dinode));
 727         if (!l_sc->sc_total && !l_sc->sc_free && !l_sc->sc_dinodes) {
 728                 spin_unlock(&sdp->sd_statfs_spin);
 729                 goto out_bh;
 730         }
 731         spin_unlock(&sdp->sd_statfs_spin);
 732
 733         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 734         if (error)
 735                 goto out_bh;
 736
 737         error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
 738         if (error)
 739                 goto out_bh2;
 740
 741         gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
 742
 743         spin_lock(&sdp->sd_statfs_spin);
 744         m_sc->sc_total += l_sc->sc_total;
 745         m_sc->sc_free += l_sc->sc_free;
 746         m_sc->sc_dinodes += l_sc->sc_dinodes;
 747         memset(l_sc, 0, sizeof(struct gfs2_statfs_change));
 748         memset(l_bh->b_data + sizeof(struct gfs2_dinode),
 749                0, sizeof(struct gfs2_statfs_change));
 750         spin_unlock(&sdp->sd_statfs_spin);
 751
 752         gfs2_trans_add_bh(m_ip->i_gl, m_bh, 1);
 753         gfs2_statfs_change_out(m_sc, m_bh->b_data + sizeof(struct gfs2_dinode));
 754
 755         gfs2_trans_end(sdp);
 756
 757 out_bh2:
 758         brelse(l_bh);
 759 out_bh:
 760         brelse(m_bh);
 761 out:
 762         gfs2_glock_dq_uninit(&gh);
 763         return error;
 764 }
 765
 766 /**
 767  * gfs2_statfs_i - Do a statfs
 768  * @sdp: the filesystem
 769  * @sg: the sg structure
 770  *
 771  * Returns: errno
 772  */
 773
 774 int gfs2_statfs_i(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
 775 {
 776         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 777         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 778
 779         spin_lock(&sdp->sd_statfs_spin);
 780
 781         *sc = *m_sc;
 782         sc->sc_total += l_sc->sc_total;
 783         sc->sc_free += l_sc->sc_free;
 784         sc->sc_dinodes += l_sc->sc_dinodes;
 785
 786         spin_unlock(&sdp->sd_statfs_spin);
 787
 788         if (sc->sc_free < 0)
 789                 sc->sc_free = 0;
 790         if (sc->sc_free > sc->sc_total)
 791                 sc->sc_free = sc->sc_total;
 792         if (sc->sc_dinodes < 0)
 793                 sc->sc_dinodes = 0;
 794
 795         return 0;
 796 }
 797
 798 /**
 799  * statfs_fill - fill in the sg for a given RG
 800  * @rgd: the RG
 801  * @sc: the sc structure
 802  *
 803  * Returns: 0 on success, -ESTALE if the LVB is invalid
 804  */
 805
 806 static int statfs_slow_fill(struct gfs2_rgrpd *rgd,
 807                             struct gfs2_statfs_change_host *sc)
 808 {
 809         gfs2_rgrp_verify(rgd);
 810         sc->sc_total += rgd->rd_data;
 811         sc->sc_free += rgd->rd_rg.rg_free;
 812         sc->sc_dinodes += rgd->rd_rg.rg_dinodes;
 813         return 0;
 814 }
 815
 816 /**
 817  * gfs2_statfs_slow - Stat a filesystem using asynchronous locking
 818  * @sdp: the filesystem
 819  * @sc: the sc info that will be returned
 820  *
 821  * Any error (other than a signal) will cause this routine to fall back
 822  * to the synchronous version.
 823  *
 824  * FIXME: This really shouldn't busy wait like this.
 825  *
 826  * Returns: errno
 827  */
 828
 829 int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
 830 {
 831         struct gfs2_holder ri_gh;
 832         struct gfs2_rgrpd *rgd_next;
 833         struct gfs2_holder *gha, *gh;
 834         unsigned int slots = 64;
 835         unsigned int x;
 836         int done;
 837         int error = 0, err;
 838
 839         memset(sc, 0, sizeof(struct gfs2_statfs_change_host));
 840         gha = kcalloc(slots, sizeof(struct gfs2_holder), GFP_KERNEL);
 841         if (!gha)
 842                 return -ENOMEM;
 843
 844         error = gfs2_rindex_hold(sdp, &ri_gh);
 845         if (error)
 846                 goto out;
 847
 848         rgd_next = gfs2_rgrpd_get_first(sdp);
 849
 850         for (;;) {
 851                 done = 1;
 852
 853                 for (x = 0; x < slots; x++) {
 854                         gh = gha + x;
 855
 856                         if (gh->gh_gl && gfs2_glock_poll(gh)) {
 857                                 err = gfs2_glock_wait(gh);
 858                                 if (err) {
 859                                         gfs2_holder_uninit(gh);
 860                                         error = err;
 861                                 } else {
 862                                         if (!error)
 863                                                 error = statfs_slow_fill(
 864                                                         gh->gh_gl->gl_object, sc);
 865                                         gfs2_glock_dq_uninit(gh);
 866                                 }
 867                         }
 868
 869                         if (gh->gh_gl)
 870                                 done = 0;
 871                         else if (rgd_next && !error) {
 872                                 error = gfs2_glock_nq_init(rgd_next->rd_gl,
 873                                                            LM_ST_SHARED,
 874                                                            GL_ASYNC,
 875                                                            gh);
 876                                 rgd_next = gfs2_rgrpd_get_next(rgd_next);
 877                                 done = 0;
 878                         }
 879
 880                         if (signal_pending(current))
 881                                 error = -ERESTARTSYS;
 882                 }
 883
 884                 if (done)
 885                         break;
 886
 887                 yield();
 888         }
 889
 890         gfs2_glock_dq_uninit(&ri_gh);
 891
 892 out:
 893         kfree(gha);
 894         return error;
 895 }
 896
 897 struct lfcc {
 898         struct list_head list;
 899         struct gfs2_holder gh;
 900 };
 901
 902 /**
 903  * gfs2_lock_fs_check_clean - Stop all writes to the FS and check that all
 904  *                            journals are clean
 905  * @sdp: the file system
 906  * @state: the state to put the transaction lock into
 907  * @t_gh: the hold on the transaction lock
 908  *
 909  * Returns: errno
 910  */
 911
 912 static int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp,
 913                                     struct gfs2_holder *t_gh)
 914 {
 915         struct gfs2_inode *ip;
 916         struct gfs2_holder ji_gh;
 917         struct gfs2_jdesc *jd;
 918         struct lfcc *lfcc;
 919         LIST_HEAD(list);
 920         struct gfs2_log_header_host lh;
 921         int error;
 922
 923         error = gfs2_jindex_hold(sdp, &ji_gh);
 924         if (error)
 925                 return error;
 926
 927         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 928                 lfcc = kmalloc(sizeof(struct lfcc), GFP_KERNEL);
 929                 if (!lfcc) {
 930                         error = -ENOMEM;
 931                         goto out;
 932                 }
 933                 ip = GFS2_I(jd->jd_inode);
 934                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &lfcc->gh);
 935                 if (error) {
 936                         kfree(lfcc);
 937                         goto out;
 938                 }
 939                 list_add(&lfcc->list, &list);
 940         }
 941
 942         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_DEFERRED,
 943                                    GL_NOCACHE, t_gh);
 944
 945         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 946                 error = gfs2_jdesc_check(jd);
 947                 if (error)
 948                         break;
 949                 error = gfs2_find_jhead(jd, &lh);
 950                 if (error)
 951                         break;
 952                 if (!(lh.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 953                         error = -EBUSY;
 954                         break;
 955                 }
 956         }
 957
 958         if (error)
 959                 gfs2_glock_dq_uninit(t_gh);
 960
 961 out:
 962         while (!list_empty(&list)) {
 963                 lfcc = list_entry(list.next, struct lfcc, list);
 964                 list_del(&lfcc->list);
 965                 gfs2_glock_dq_uninit(&lfcc->gh);
 966                 kfree(lfcc);
 967         }
 968         gfs2_glock_dq_uninit(&ji_gh);
 969         return error;
 970 }
 971
 972 /**
 973  * gfs2_freeze_fs - freezes the file system
 974  * @sdp: the file system
 975  *
 976  * This function flushes data and meta data for all machines by
 977  * aquiring the transaction log exclusively.  All journals are
 978  * ensured to be in a clean state as well.
 979  *
 980  * Returns: errno
 981  */
 982
 983 int gfs2_freeze_fs(struct gfs2_sbd *sdp)
 984 {
 985         int error = 0;
 986
 987         mutex_lock(&sdp->sd_freeze_lock);
 988
 989         if (!sdp->sd_freeze_count++) {
 990                 error = gfs2_lock_fs_check_clean(sdp, &sdp->sd_freeze_gh);
 991                 if (error)
 992                         sdp->sd_freeze_count--;
 993         }
 994
 995         mutex_unlock(&sdp->sd_freeze_lock);
 996
 997         return error;
 998 }
 999
1000 /**
1001  * gfs2_unfreeze_fs - unfreezes the file system
1002  * @sdp: the file system
1003  *
1004  * This function allows the file system to proceed by unlocking
1005  * the exclusively held transaction lock.  Other GFS2 nodes are
1006  * now free to acquire the lock shared and go on with their lives.
1007  *
1008  */
1009
1010 void gfs2_unfreeze_fs(struct gfs2_sbd *sdp)
1011 {
1012         mutex_lock(&sdp->sd_freeze_lock);
1013
1014         if (sdp->sd_freeze_count && !--sdp->sd_freeze_count)
1015                 gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
1016
1017         mutex_unlock(&sdp->sd_freeze_lock);
1018 }
1019