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) 2004-2006 Red Hat, Inc.  All rights reserved.
   4  *
   5  * This copyrighted material is made available to anyone wishing to use,
   6  * modify, copy, or redistribute it subject to the terms and conditions
   7  * of the GNU General Public License v.2.
   8  */
   9
  10 #include <linux/sched.h>
  11 #include <linux/slab.h>
  12 #include <linux/spinlock.h>
  13 #include <linux/completion.h>
  14 #include <linux/buffer_head.h>
  15 #include <linux/crc32.h>
  16 #include <linux/gfs2_ondisk.h>
  17 #include <linux/bio.h>
  18
  19 #include "gfs2.h"
  20 #include "lm_interface.h"
  21 #include "incore.h"
  22 #include "bmap.h"
  23 #include "dir.h"
  24 #include "format.h"
  25 #include "glock.h"
  26 #include "glops.h"
  27 #include "inode.h"
  28 #include "log.h"
  29 #include "meta_io.h"
  30 #include "quota.h"
  31 #include "recovery.h"
  32 #include "rgrp.h"
  33 #include "super.h"
  34 #include "trans.h"
  35 #include "util.h"
  36
  37 /**
  38  * gfs2_tune_init - Fill a gfs2_tune structure with default values
  39  * @gt: tune
  40  *
  41  */
  42
  43 void gfs2_tune_init(struct gfs2_tune *gt)
  44 {
  45         spin_lock_init(&gt->gt_spin);
  46
  47         gt->gt_ilimit = 100;
  48         gt->gt_ilimit_tries = 3;
  49         gt->gt_ilimit_min = 1;
  50         gt->gt_demote_secs = 300;
  51         gt->gt_incore_log_blocks = 1024;
  52         gt->gt_log_flush_secs = 60;
  53         gt->gt_jindex_refresh_secs = 60;
  54         gt->gt_scand_secs = 15;
  55         gt->gt_recoverd_secs = 60;
  56         gt->gt_logd_secs = 1;
  57         gt->gt_quotad_secs = 5;
  58         gt->gt_quota_simul_sync = 64;
  59         gt->gt_quota_warn_period = 10;
  60         gt->gt_quota_scale_num = 1;
  61         gt->gt_quota_scale_den = 1;
  62         gt->gt_quota_cache_secs = 300;
  63         gt->gt_quota_quantum = 60;
  64         gt->gt_atime_quantum = 3600;
  65         gt->gt_new_files_jdata = 0;
  66         gt->gt_new_files_directio = 0;
  67         gt->gt_max_atomic_write = 4 << 20;
  68         gt->gt_max_readahead = 1 << 18;
  69         gt->gt_lockdump_size = 131072;
  70         gt->gt_stall_secs = 600;
  71         gt->gt_complain_secs = 10;
  72         gt->gt_reclaim_limit = 5000;
  73         gt->gt_entries_per_readdir = 32;
  74         gt->gt_prefetch_secs = 10;
  75         gt->gt_greedy_default = HZ / 10;
  76         gt->gt_greedy_quantum = HZ / 40;
  77         gt->gt_greedy_max = HZ / 4;
  78         gt->gt_statfs_quantum = 30;
  79         gt->gt_statfs_slow = 0;
  80 }
  81
  82 /**
  83  * gfs2_check_sb - Check superblock
  84  * @sdp: the filesystem
  85  * @sb: The superblock
  86  * @silent: Don't print a message if the check fails
  87  *
  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
  90  * changed.
  91  */
  92
  93 int gfs2_check_sb(struct gfs2_sbd *sdp, struct gfs2_sb *sb, int silent)
  94 {
  95         unsigned int x;
  96
  97         if (sb->sb_header.mh_magic != GFS2_MAGIC ||
  98             sb->sb_header.mh_type != GFS2_METATYPE_SB) {
  99                 if (!silent)
 100                         printk(KERN_WARNING "GFS2: not a GFS2 filesystem\n");
 101                 return -EINVAL;
 102         }
 103
 104         /*  If format numbers match exactly, we're done.  */
 105
 106         if (sb->sb_fs_format == GFS2_FORMAT_FS &&
 107             sb->sb_multihost_format == GFS2_FORMAT_MULTI)
 108                 return 0;
 109
 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)
 113                                 break;
 114
 115                 if (!gfs2_old_fs_formats[x]) {
 116                         printk(KERN_WARNING
 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);
 121                         printk(KERN_WARNING
 122                                "GFS2: I don't know how to upgrade this FS\n");
 123                         return -EINVAL;
 124                 }
 125         }
 126
 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)
 131                                 break;
 132
 133                 if (!gfs2_old_multihost_formats[x]) {
 134                         printk(KERN_WARNING
 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);
 139                         printk(KERN_WARNING
 140                                "GFS2: I don't know how to upgrade this FS\n");
 141                         return -EINVAL;
 142                 }
 143         }
 144
 145         if (!sdp->sd_args.ar_upgrade) {
 146                 printk(KERN_WARNING
 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);
 151                 printk(KERN_INFO
 152                        "GFS2: Use the \"upgrade\" mount option to upgrade "
 153                        "the FS\n");
 154                 printk(KERN_INFO "GFS2: See the manual for more details\n");
 155                 return -EINVAL;
 156         }
 157
 158         return 0;
 159 }
 160
 161
 162 static int end_bio_io_page(struct bio *bio, unsigned int bytes_done, int error)
 163 {
 164         struct page *page = bio->bi_private;
 165         if (bio->bi_size)
 166                 return 1;
 167
 168         if (!error)
 169                 SetPageUptodate(page);
 170         else
 171                 printk(KERN_WARNING "gfs2: error %d reading superblock\n", error);
 172         unlock_page(page);
 173         return 0;
 174 }
 175
 176 static struct page *gfs2_read_super(struct super_block *sb, sector_t sector)
 177 {
 178         struct page *page;
 179         struct bio *bio;
 180
 181         page = alloc_page(GFP_KERNEL);
 182         if (unlikely(!page))
 183                 return NULL;
 184
 185         ClearPageUptodate(page);
 186         ClearPageDirty(page);
 187         lock_page(page);
 188
 189         bio = bio_alloc(GFP_KERNEL, 1);
 190         if (unlikely(!bio)) {
 191                 __free_page(page);
 192                 return NULL;
 193         }
 194
 195         bio->bi_sector = sector;
 196         bio->bi_bdev = sb->s_bdev;
 197         bio_add_page(bio, page, PAGE_SIZE, 0);
 198
 199         bio->bi_end_io = end_bio_io_page;
 200         bio->bi_private = page;
 201         submit_bio(READ_SYNC, bio);
 202         wait_on_page_locked(page);
 203         bio_put(bio);
 204         if (!PageUptodate(page)) {
 205                 __free_page(page);
 206                 return NULL;
 207         }
 208         return page;
 209 }
 210
 211 /**
 212  * gfs2_read_sb - Read super block
 213  * @sdp: The GFS2 superblock
 214  * @gl: the glock for the superblock (assumed to be held)
 215  * @silent: Don't print message if mount fails
 216  *
 217  */
 218
 219 int gfs2_read_sb(struct gfs2_sbd *sdp, struct gfs2_glock *gl, int silent)
 220 {
 221         uint32_t hash_blocks, ind_blocks, leaf_blocks;
 222         uint32_t tmp_blocks;
 223         unsigned int x;
 224         int error;
 225         struct page *page;
 226         char *sb;
 227
 228         page = gfs2_read_super(sdp->sd_vfs, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift);
 229         if (!page) {
 230                 if (!silent)
 231                         fs_err(sdp, "can't read superblock\n");
 232                 return -EIO;
 233         }
 234         sb = kmap(page);
 235         gfs2_sb_in(&sdp->sd_sb, sb);
 236         kunmap(page);
 237         __free_page(page);
 238
 239         error = gfs2_check_sb(sdp, &sdp->sd_sb, silent);
 240         if (error)
 241                 return error;
 242
 243         sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
 244                                GFS2_BASIC_BLOCK_SHIFT;
 245         sdp->sd_fsb2bb = 1 << sdp->sd_fsb2bb_shift;
 246         sdp->sd_diptrs = (sdp->sd_sb.sb_bsize -
 247                           sizeof(struct gfs2_dinode)) / sizeof(uint64_t);
 248         sdp->sd_inptrs = (sdp->sd_sb.sb_bsize -
 249                           sizeof(struct gfs2_meta_header)) / sizeof(uint64_t);
 250         sdp->sd_jbsize = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header);
 251         sdp->sd_hash_bsize = sdp->sd_sb.sb_bsize / 2;
 252         sdp->sd_hash_bsize_shift = sdp->sd_sb.sb_bsize_shift - 1;
 253         sdp->sd_hash_ptrs = sdp->sd_hash_bsize / sizeof(uint64_t);
 254         sdp->sd_qc_per_block = (sdp->sd_sb.sb_bsize -
 255                                 sizeof(struct gfs2_meta_header)) /
 256                                 sizeof(struct gfs2_quota_change);
 257
 258         /* Compute maximum reservation required to add a entry to a directory */
 259
 260         hash_blocks = DIV_ROUND_UP(sizeof(uint64_t) * (1 << GFS2_DIR_MAX_DEPTH),
 261                              sdp->sd_jbsize);
 262
 263         ind_blocks = 0;
 264         for (tmp_blocks = hash_blocks; tmp_blocks > sdp->sd_diptrs;) {
 265                 tmp_blocks = DIV_ROUND_UP(tmp_blocks, sdp->sd_inptrs);
 266                 ind_blocks += tmp_blocks;
 267         }
 268
 269         leaf_blocks = 2 + GFS2_DIR_MAX_DEPTH;
 270
 271         sdp->sd_max_dirres = hash_blocks + ind_blocks + leaf_blocks;
 272
 273         sdp->sd_heightsize[0] = sdp->sd_sb.sb_bsize -
 274                                 sizeof(struct gfs2_dinode);
 275         sdp->sd_heightsize[1] = sdp->sd_sb.sb_bsize * sdp->sd_diptrs;
 276         for (x = 2;; x++) {
 277                 uint64_t space, d;
 278                 uint32_t m;
 279
 280                 space = sdp->sd_heightsize[x - 1] * sdp->sd_inptrs;
 281                 d = space;
 282                 m = do_div(d, sdp->sd_inptrs);
 283
 284                 if (d != sdp->sd_heightsize[x - 1] || m)
 285                         break;
 286                 sdp->sd_heightsize[x] = space;
 287         }
 288         sdp->sd_max_height = x;
 289         gfs2_assert(sdp, sdp->sd_max_height <= GFS2_MAX_META_HEIGHT);
 290
 291         sdp->sd_jheightsize[0] = sdp->sd_sb.sb_bsize -
 292                                  sizeof(struct gfs2_dinode);
 293         sdp->sd_jheightsize[1] = sdp->sd_jbsize * sdp->sd_diptrs;
 294         for (x = 2;; x++) {
 295                 uint64_t space, d;
 296                 uint32_t m;
 297
 298                 space = sdp->sd_jheightsize[x - 1] * sdp->sd_inptrs;
 299                 d = space;
 300                 m = do_div(d, sdp->sd_inptrs);
 301
 302                 if (d != sdp->sd_jheightsize[x - 1] || m)
 303                         break;
 304                 sdp->sd_jheightsize[x] = space;
 305         }
 306         sdp->sd_max_jheight = x;
 307         gfs2_assert(sdp, sdp->sd_max_jheight <= GFS2_MAX_META_HEIGHT);
 308
 309         return 0;
 310 }
 311
 312 /**
 313  * gfs2_jindex_hold - Grab a lock on the jindex
 314  * @sdp: The GFS2 superblock
 315  * @ji_gh: the holder for the jindex glock
 316  *
 317  * This is very similar to the gfs2_rindex_hold() function, except that
 318  * in general we hold the jindex lock for longer periods of time and
 319  * we grab it far less frequently (in general) then the rgrp lock.
 320  *
 321  * Returns: errno
 322  */
 323
 324 int gfs2_jindex_hold(struct gfs2_sbd *sdp, struct gfs2_holder *ji_gh)
 325 {
 326         struct gfs2_inode *dip = GFS2_I(sdp->sd_jindex);
 327         struct qstr name;
 328         char buf[20];
 329         struct gfs2_jdesc *jd;
 330         int error;
 331
 332         name.name = buf;
 333
 334         mutex_lock(&sdp->sd_jindex_mutex);
 335
 336         for (;;) {
 337                 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED,
 338                                            GL_LOCAL_EXCL, ji_gh);
 339                 if (error)
 340                         break;
 341
 342                 name.len = sprintf(buf, "journal%u", sdp->sd_journals);
 343                 name.hash = gfs2_disk_hash(name.name, name.len);
 344
 345                 error = gfs2_dir_search(sdp->sd_jindex, &name, NULL, NULL);
 346                 if (error == -ENOENT) {
 347                         error = 0;
 348                         break;
 349                 }
 350
 351                 gfs2_glock_dq_uninit(ji_gh);
 352
 353                 if (error)
 354                         break;
 355
 356                 error = -ENOMEM;
 357                 jd = kzalloc(sizeof(struct gfs2_jdesc), GFP_KERNEL);
 358                 if (!jd)
 359                         break;
 360
 361                 jd->jd_inode = gfs2_lookupi(sdp->sd_jindex, &name, 1, NULL);
 362                 if (!jd->jd_inode || IS_ERR(jd->jd_inode)) {
 363                         if (!jd->jd_inode)
 364                                 error = -ENOENT;
 365                         else
 366                                 error = PTR_ERR(jd->jd_inode);
 367                         kfree(jd);
 368                         break;
 369                 }
 370
 371                 spin_lock(&sdp->sd_jindex_spin);
 372                 jd->jd_jid = sdp->sd_journals++;
 373                 list_add_tail(&jd->jd_list, &sdp->sd_jindex_list);
 374                 spin_unlock(&sdp->sd_jindex_spin);
 375         }
 376
 377         mutex_unlock(&sdp->sd_jindex_mutex);
 378
 379         return error;
 380 }
 381
 382 /**
 383  * gfs2_jindex_free - Clear all the journal index information
 384  * @sdp: The GFS2 superblock
 385  *
 386  */
 387
 388 void gfs2_jindex_free(struct gfs2_sbd *sdp)
 389 {
 390         struct list_head list;
 391         struct gfs2_jdesc *jd;
 392
 393         spin_lock(&sdp->sd_jindex_spin);
 394         list_add(&list, &sdp->sd_jindex_list);
 395         list_del_init(&sdp->sd_jindex_list);
 396         sdp->sd_journals = 0;
 397         spin_unlock(&sdp->sd_jindex_spin);
 398
 399         while (!list_empty(&list)) {
 400                 jd = list_entry(list.next, struct gfs2_jdesc, jd_list);
 401                 list_del(&jd->jd_list);
 402                 iput(jd->jd_inode);
 403                 kfree(jd);
 404         }
 405 }
 406
 407 static struct gfs2_jdesc *jdesc_find_i(struct list_head *head, unsigned int jid)
 408 {
 409         struct gfs2_jdesc *jd;
 410         int found = 0;
 411
 412         list_for_each_entry(jd, head, jd_list) {
 413                 if (jd->jd_jid == jid) {
 414                         found = 1;
 415                         break;
 416                 }
 417         }
 418
 419         if (!found)
 420                 jd = NULL;
 421
 422         return jd;
 423 }
 424
 425 struct gfs2_jdesc *gfs2_jdesc_find(struct gfs2_sbd *sdp, unsigned int jid)
 426 {
 427         struct gfs2_jdesc *jd;
 428
 429         spin_lock(&sdp->sd_jindex_spin);
 430         jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
 431         spin_unlock(&sdp->sd_jindex_spin);
 432
 433         return jd;
 434 }
 435
 436 void gfs2_jdesc_make_dirty(struct gfs2_sbd *sdp, unsigned int jid)
 437 {
 438         struct gfs2_jdesc *jd;
 439
 440         spin_lock(&sdp->sd_jindex_spin);
 441         jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
 442         if (jd)
 443                 jd->jd_dirty = 1;
 444         spin_unlock(&sdp->sd_jindex_spin);
 445 }
 446
 447 struct gfs2_jdesc *gfs2_jdesc_find_dirty(struct gfs2_sbd *sdp)
 448 {
 449         struct gfs2_jdesc *jd;
 450         int found = 0;
 451
 452         spin_lock(&sdp->sd_jindex_spin);
 453
 454         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 455                 if (jd->jd_dirty) {
 456                         jd->jd_dirty = 0;
 457                         found = 1;
 458                         break;
 459                 }
 460         }
 461         spin_unlock(&sdp->sd_jindex_spin);
 462
 463         if (!found)
 464                 jd = NULL;
 465
 466         return jd;
 467 }
 468
 469 int gfs2_jdesc_check(struct gfs2_jdesc *jd)
 470 {
 471         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
 472         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 473         int ar;
 474         int error;
 475
 476         if (ip->i_di.di_size < (8 << 20) || ip->i_di.di_size > (1 << 30) ||
 477             (ip->i_di.di_size & (sdp->sd_sb.sb_bsize - 1))) {
 478                 gfs2_consist_inode(ip);
 479                 return -EIO;
 480         }
 481         jd->jd_blocks = ip->i_di.di_size >> sdp->sd_sb.sb_bsize_shift;
 482
 483         error = gfs2_write_alloc_required(ip, 0, ip->i_di.di_size, &ar);
 484         if (!error && ar) {
 485                 gfs2_consist_inode(ip);
 486                 error = -EIO;
 487         }
 488
 489         return error;
 490 }
 491
 492 /**
 493  * gfs2_make_fs_rw - Turn a Read-Only FS into a Read-Write one
 494  * @sdp: the filesystem
 495  *
 496  * Returns: errno
 497  */
 498
 499 int gfs2_make_fs_rw(struct gfs2_sbd *sdp)
 500 {
 501         struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
 502         struct gfs2_glock *j_gl = ip->i_gl;
 503         struct gfs2_holder t_gh;
 504         struct gfs2_log_header head;
 505         int error;
 506
 507         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
 508                                    GL_LOCAL_EXCL, &t_gh);
 509         if (error)
 510                 return error;
 511
 512         gfs2_meta_cache_flush(ip);
 513         j_gl->gl_ops->go_inval(j_gl, DIO_METADATA | DIO_DATA);
 514
 515         error = gfs2_find_jhead(sdp->sd_jdesc, &head);
 516         if (error)
 517                 goto fail;
 518
 519         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 520                 gfs2_consist(sdp);
 521                 error = -EIO;
 522                 goto fail;
 523         }
 524
 525         /*  Initialize some head of the log stuff  */
 526         sdp->sd_log_sequence = head.lh_sequence + 1;
 527         gfs2_log_pointers_init(sdp, head.lh_blkno);
 528
 529         error = gfs2_quota_init(sdp);
 530         if (error)
 531                 goto fail_unlinked;
 532
 533         set_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 534
 535         gfs2_glock_dq_uninit(&t_gh);
 536
 537         return 0;
 538
 539  fail_unlinked:
 540
 541  fail:
 542         t_gh.gh_flags |= GL_NOCACHE;
 543         gfs2_glock_dq_uninit(&t_gh);
 544
 545         return error;
 546 }
 547
 548 /**
 549  * gfs2_make_fs_ro - Turn a Read-Write FS into a Read-Only one
 550  * @sdp: the filesystem
 551  *
 552  * Returns: errno
 553  */
 554
 555 int gfs2_make_fs_ro(struct gfs2_sbd *sdp)
 556 {
 557         struct gfs2_holder t_gh;
 558         int error;
 559
 560         gfs2_quota_sync(sdp);
 561         gfs2_statfs_sync(sdp);
 562
 563         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
 564                                 GL_LOCAL_EXCL | GL_NOCACHE,
 565                                 &t_gh);
 566         if (error && !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
 567                 return error;
 568
 569         gfs2_meta_syncfs(sdp);
 570         gfs2_log_shutdown(sdp);
 571
 572         clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 573
 574         if (t_gh.gh_gl)
 575                 gfs2_glock_dq_uninit(&t_gh);
 576
 577         gfs2_quota_cleanup(sdp);
 578
 579         return error;
 580 }
 581
 582 int gfs2_statfs_init(struct gfs2_sbd *sdp)
 583 {
 584         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 585         struct gfs2_statfs_change *m_sc = &sdp->sd_statfs_master;
 586         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 587         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 588         struct buffer_head *m_bh, *l_bh;
 589         struct gfs2_holder gh;
 590         int error;
 591
 592         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 593                                    &gh);
 594         if (error)
 595                 return error;
 596
 597         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 598         if (error)
 599                 goto out;
 600
 601         if (sdp->sd_args.ar_spectator) {
 602                 spin_lock(&sdp->sd_statfs_spin);
 603                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 604                                       sizeof(struct gfs2_dinode));
 605                 spin_unlock(&sdp->sd_statfs_spin);
 606         } else {
 607                 error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 608                 if (error)
 609                         goto out_m_bh;
 610
 611                 spin_lock(&sdp->sd_statfs_spin);
 612                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 613                                       sizeof(struct gfs2_dinode));
 614                 gfs2_statfs_change_in(l_sc, l_bh->b_data +
 615                                       sizeof(struct gfs2_dinode));
 616                 spin_unlock(&sdp->sd_statfs_spin);
 617
 618                 brelse(l_bh);
 619         }
 620
 621  out_m_bh:
 622         brelse(m_bh);
 623
 624  out:
 625         gfs2_glock_dq_uninit(&gh);
 626
 627         return 0;
 628 }
 629
 630 void gfs2_statfs_change(struct gfs2_sbd *sdp, int64_t total, int64_t free,
 631                         int64_t dinodes)
 632 {
 633         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 634         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 635         struct buffer_head *l_bh;
 636         int error;
 637
 638         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 639         if (error)
 640                 return;
 641
 642         mutex_lock(&sdp->sd_statfs_mutex);
 643         gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
 644         mutex_unlock(&sdp->sd_statfs_mutex);
 645
 646         spin_lock(&sdp->sd_statfs_spin);
 647         l_sc->sc_total += total;
 648         l_sc->sc_free += free;
 649         l_sc->sc_dinodes += dinodes;
 650         gfs2_statfs_change_out(l_sc, l_bh->b_data +
 651                                sizeof(struct gfs2_dinode));
 652         spin_unlock(&sdp->sd_statfs_spin);
 653
 654         brelse(l_bh);
 655 }
 656
 657 int gfs2_statfs_sync(struct gfs2_sbd *sdp)
 658 {
 659         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 660         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 661         struct gfs2_statfs_change *m_sc = &sdp->sd_statfs_master;
 662         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 663         struct gfs2_holder gh;
 664         struct buffer_head *m_bh, *l_bh;
 665         int error;
 666
 667         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 668                                    &gh);
 669         if (error)
 670                 return error;
 671
 672         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 673         if (error)
 674                 goto out;
 675
 676         spin_lock(&sdp->sd_statfs_spin);
 677         gfs2_statfs_change_in(m_sc, m_bh->b_data +
 678                               sizeof(struct gfs2_dinode));
 679         if (!l_sc->sc_total && !l_sc->sc_free && !l_sc->sc_dinodes) {
 680                 spin_unlock(&sdp->sd_statfs_spin);
 681                 goto out_bh;
 682         }
 683         spin_unlock(&sdp->sd_statfs_spin);
 684
 685         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 686         if (error)
 687                 goto out_bh;
 688
 689         error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
 690         if (error)
 691                 goto out_bh2;
 692
 693         mutex_lock(&sdp->sd_statfs_mutex);
 694         gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
 695         mutex_unlock(&sdp->sd_statfs_mutex);
 696
 697         spin_lock(&sdp->sd_statfs_spin);
 698         m_sc->sc_total += l_sc->sc_total;
 699         m_sc->sc_free += l_sc->sc_free;
 700         m_sc->sc_dinodes += l_sc->sc_dinodes;
 701         memset(l_sc, 0, sizeof(struct gfs2_statfs_change));
 702         memset(l_bh->b_data + sizeof(struct gfs2_dinode),
 703                0, sizeof(struct gfs2_statfs_change));
 704         spin_unlock(&sdp->sd_statfs_spin);
 705
 706         gfs2_trans_add_bh(m_ip->i_gl, m_bh, 1);
 707         gfs2_statfs_change_out(m_sc, m_bh->b_data + sizeof(struct gfs2_dinode));
 708
 709         gfs2_trans_end(sdp);
 710
 711  out_bh2:
 712         brelse(l_bh);
 713
 714  out_bh:
 715         brelse(m_bh);
 716
 717  out:
 718         gfs2_glock_dq_uninit(&gh);
 719
 720         return error;
 721 }
 722
 723 /**
 724  * gfs2_statfs_i - Do a statfs
 725  * @sdp: the filesystem
 726  * @sg: the sg structure
 727  *
 728  * Returns: errno
 729  */
 730
 731 int gfs2_statfs_i(struct gfs2_sbd *sdp, struct gfs2_statfs_change *sc)
 732 {
 733         struct gfs2_statfs_change *m_sc = &sdp->sd_statfs_master;
 734         struct gfs2_statfs_change *l_sc = &sdp->sd_statfs_local;
 735
 736         spin_lock(&sdp->sd_statfs_spin);
 737
 738         *sc = *m_sc;
 739         sc->sc_total += l_sc->sc_total;
 740         sc->sc_free += l_sc->sc_free;
 741         sc->sc_dinodes += l_sc->sc_dinodes;
 742
 743         spin_unlock(&sdp->sd_statfs_spin);
 744
 745         if (sc->sc_free < 0)
 746                 sc->sc_free = 0;
 747         if (sc->sc_free > sc->sc_total)
 748                 sc->sc_free = sc->sc_total;
 749         if (sc->sc_dinodes < 0)
 750                 sc->sc_dinodes = 0;
 751
 752         return 0;
 753 }
 754
 755 /**
 756  * statfs_fill - fill in the sg for a given RG
 757  * @rgd: the RG
 758  * @sc: the sc structure
 759  *
 760  * Returns: 0 on success, -ESTALE if the LVB is invalid
 761  */
 762
 763 static int statfs_slow_fill(struct gfs2_rgrpd *rgd,
 764                             struct gfs2_statfs_change *sc)
 765 {
 766         gfs2_rgrp_verify(rgd);
 767         sc->sc_total += rgd->rd_ri.ri_data;
 768         sc->sc_free += rgd->rd_rg.rg_free;
 769         sc->sc_dinodes += rgd->rd_rg.rg_dinodes;
 770         return 0;
 771 }
 772
 773 /**
 774  * gfs2_statfs_slow - Stat a filesystem using asynchronous locking
 775  * @sdp: the filesystem
 776  * @sc: the sc info that will be returned
 777  *
 778  * Any error (other than a signal) will cause this routine to fall back
 779  * to the synchronous version.
 780  *
 781  * FIXME: This really shouldn't busy wait like this.
 782  *
 783  * Returns: errno
 784  */
 785
 786 int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change *sc)
 787 {
 788         struct gfs2_holder ri_gh;
 789         struct gfs2_rgrpd *rgd_next;
 790         struct gfs2_holder *gha, *gh;
 791         unsigned int slots = 64;
 792         unsigned int x;
 793         int done;
 794         int error = 0, err;
 795
 796         memset(sc, 0, sizeof(struct gfs2_statfs_change));
 797         gha = kcalloc(slots, sizeof(struct gfs2_holder), GFP_KERNEL);
 798         if (!gha)
 799                 return -ENOMEM;
 800
 801         error = gfs2_rindex_hold(sdp, &ri_gh);
 802         if (error)
 803                 goto out;
 804
 805         rgd_next = gfs2_rgrpd_get_first(sdp);
 806
 807         for (;;) {
 808                 done = 1;
 809
 810                 for (x = 0; x < slots; x++) {
 811                         gh = gha + x;
 812
 813                         if (gh->gh_gl && gfs2_glock_poll(gh)) {
 814                                 err = gfs2_glock_wait(gh);
 815                                 if (err) {
 816                                         gfs2_holder_uninit(gh);
 817                                         error = err;
 818                                 } else {
 819                                         if (!error)
 820                                                 error = statfs_slow_fill(
 821                                                         gh->gh_gl->gl_object, sc);
 822                                         gfs2_glock_dq_uninit(gh);
 823                                 }
 824                         }
 825
 826                         if (gh->gh_gl)
 827                                 done = 0;
 828                         else if (rgd_next && !error) {
 829                                 error = gfs2_glock_nq_init(rgd_next->rd_gl,
 830                                                            LM_ST_SHARED,
 831                                                            GL_ASYNC,
 832                                                            gh);
 833                                 rgd_next = gfs2_rgrpd_get_next(rgd_next);
 834                                 done = 0;
 835                         }
 836
 837                         if (signal_pending(current))
 838                                 error = -ERESTARTSYS;
 839                 }
 840
 841                 if (done)
 842                         break;
 843
 844                 yield();
 845         }
 846
 847         gfs2_glock_dq_uninit(&ri_gh);
 848
 849  out:
 850         kfree(gha);
 851
 852         return error;
 853 }
 854
 855 struct lfcc {
 856         struct list_head list;
 857         struct gfs2_holder gh;
 858 };
 859
 860 /**
 861  * gfs2_lock_fs_check_clean - Stop all writes to the FS and check that all
 862  *                            journals are clean
 863  * @sdp: the file system
 864  * @state: the state to put the transaction lock into
 865  * @t_gh: the hold on the transaction lock
 866  *
 867  * Returns: errno
 868  */
 869
 870 static int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp,
 871                                     struct gfs2_holder *t_gh)
 872 {
 873         struct gfs2_inode *ip;
 874         struct gfs2_holder ji_gh;
 875         struct gfs2_jdesc *jd;
 876         struct lfcc *lfcc;
 877         LIST_HEAD(list);
 878         struct gfs2_log_header lh;
 879         int error;
 880
 881         error = gfs2_jindex_hold(sdp, &ji_gh);
 882         if (error)
 883                 return error;
 884
 885         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 886                 lfcc = kmalloc(sizeof(struct lfcc), GFP_KERNEL);
 887                 if (!lfcc) {
 888                         error = -ENOMEM;
 889                         goto out;
 890                 }
 891                 ip = GFS2_I(jd->jd_inode);
 892                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &lfcc->gh);
 893                 if (error) {
 894                         kfree(lfcc);
 895                         goto out;
 896                 }
 897                 list_add(&lfcc->list, &list);
 898         }
 899
 900         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_DEFERRED,
 901                                LM_FLAG_PRIORITY | GL_NOCACHE,
 902                                t_gh);
 903
 904         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 905                 error = gfs2_jdesc_check(jd);
 906                 if (error)
 907                         break;
 908                 error = gfs2_find_jhead(jd, &lh);
 909                 if (error)
 910                         break;
 911                 if (!(lh.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 912                         error = -EBUSY;
 913                         break;
 914                 }
 915         }
 916
 917         if (error)
 918                 gfs2_glock_dq_uninit(t_gh);
 919
 920  out:
 921         while (!list_empty(&list)) {
 922                 lfcc = list_entry(list.next, struct lfcc, list);
 923                 list_del(&lfcc->list);
 924                 gfs2_glock_dq_uninit(&lfcc->gh);
 925                 kfree(lfcc);
 926         }
 927         gfs2_glock_dq_uninit(&ji_gh);
 928
 929         return error;
 930 }
 931
 932 /**
 933  * gfs2_freeze_fs - freezes the file system
 934  * @sdp: the file system
 935  *
 936  * This function flushes data and meta data for all machines by
 937  * aquiring the transaction log exclusively.  All journals are
 938  * ensured to be in a clean state as well.
 939  *
 940  * Returns: errno
 941  */
 942
 943 int gfs2_freeze_fs(struct gfs2_sbd *sdp)
 944 {
 945         int error = 0;
 946
 947         mutex_lock(&sdp->sd_freeze_lock);
 948
 949         if (!sdp->sd_freeze_count++) {
 950                 error = gfs2_lock_fs_check_clean(sdp, &sdp->sd_freeze_gh);
 951                 if (error)
 952                         sdp->sd_freeze_count--;
 953         }
 954
 955         mutex_unlock(&sdp->sd_freeze_lock);
 956
 957         return error;
 958 }
 959
 960 /**
 961  * gfs2_unfreeze_fs - unfreezes the file system
 962  * @sdp: the file system
 963  *
 964  * This function allows the file system to proceed by unlocking
 965  * the exclusively held transaction lock.  Other GFS2 nodes are
 966  * now free to acquire the lock shared and go on with their lives.
 967  *
 968  */
 969
 970 void gfs2_unfreeze_fs(struct gfs2_sbd *sdp)
 971 {
 972         mutex_lock(&sdp->sd_freeze_lock);
 973
 974         if (sdp->sd_freeze_count && !--sdp->sd_freeze_count)
 975                 gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
 976
 977         mutex_unlock(&sdp->sd_freeze_lock);
 978 }
 979