fs/gfs2/log.c

   1 /*
   2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3  * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
   4  *
   5  * This copyrighted material is made available to anyone wishing to use,
   6  * modify, copy, or redistribute it subject to the terms and conditions
   7  * of the GNU General Public License version 2.
   8  */
   9
  10 #include <linux/sched.h>
  11 #include <linux/slab.h>
  12 #include <linux/spinlock.h>
  13 #include <linux/completion.h>
  14 #include <linux/buffer_head.h>
  15 #include <linux/gfs2_ondisk.h>
  16 #include <linux/crc32.h>
  17 #include <linux/lm_interface.h>
  18 #include <linux/delay.h>
  19
  20 #include "gfs2.h"
  21 #include "incore.h"
  22 #include "bmap.h"
  23 #include "glock.h"
  24 #include "log.h"
  25 #include "lops.h"
  26 #include "meta_io.h"
  27 #include "util.h"
  28 #include "dir.h"
  29
  30 #define PULL 1
  31
  32 /**
  33  * gfs2_struct2blk - compute stuff
  34  * @sdp: the filesystem
  35  * @nstruct: the number of structures
  36  * @ssize: the size of the structures
  37  *
  38  * Compute the number of log descriptor blocks needed to hold a certain number
  39  * of structures of a certain size.
  40  *
  41  * Returns: the number of blocks needed (minimum is always 1)
  42  */
  43
  44 unsigned int gfs2_struct2blk(struct gfs2_sbd *sdp, unsigned int nstruct,
  45                              unsigned int ssize)
  46 {
  47         unsigned int blks;
  48         unsigned int first, second;
  49
  50         blks = 1;
  51         first = (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_log_descriptor)) / ssize;
  52
  53         if (nstruct > first) {
  54                 second = (sdp->sd_sb.sb_bsize -
  55                           sizeof(struct gfs2_meta_header)) / ssize;
  56                 blks += DIV_ROUND_UP(nstruct - first, second);
  57         }
  58
  59         return blks;
  60 }
  61
  62 /**
  63  * gfs2_ail1_start_one - Start I/O on a part of the AIL
  64  * @sdp: the filesystem
  65  * @tr: the part of the AIL
  66  *
  67  */
  68
  69 static void gfs2_ail1_start_one(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
  70 {
  71         struct gfs2_bufdata *bd, *s;
  72         struct buffer_head *bh;
  73         int retry;
  74
  75         BUG_ON(!spin_is_locked(&sdp->sd_log_lock));
  76
  77         do {
  78                 retry = 0;
  79
  80                 list_for_each_entry_safe_reverse(bd, s, &ai->ai_ail1_list,
  81                                                  bd_ail_st_list) {
  82                         bh = bd->bd_bh;
  83
  84                         gfs2_assert(sdp, bd->bd_ail == ai);
  85
  86                         if (!buffer_busy(bh)) {
  87                                 if (!buffer_uptodate(bh)) {
  88                                         gfs2_log_unlock(sdp);
  89                                         gfs2_io_error_bh(sdp, bh);
  90                                         gfs2_log_lock(sdp);
  91                                 }
  92                                 list_move(&bd->bd_ail_st_list, &ai->ai_ail2_list);
  93                                 continue;
  94                         }
  95
  96                         if (!buffer_dirty(bh))
  97                                 continue;
  98
  99                         list_move(&bd->bd_ail_st_list, &ai->ai_ail1_list);
 100
 101                         gfs2_log_unlock(sdp);
 102                         wait_on_buffer(bh);
 103                         ll_rw_block(WRITE, 1, &bh);
 104                         gfs2_log_lock(sdp);
 105
 106                         retry = 1;
 107                         break;
 108                 }
 109         } while (retry);
 110 }
 111
 112 /**
 113  * gfs2_ail1_empty_one - Check whether or not a trans in the AIL has been synced
 114  * @sdp: the filesystem
 115  * @ai: the AIL entry
 116  *
 117  */
 118
 119 static int gfs2_ail1_empty_one(struct gfs2_sbd *sdp, struct gfs2_ail *ai, int flags)
 120 {
 121         struct gfs2_bufdata *bd, *s;
 122         struct buffer_head *bh;
 123
 124         list_for_each_entry_safe_reverse(bd, s, &ai->ai_ail1_list,
 125                                          bd_ail_st_list) {
 126                 bh = bd->bd_bh;
 127
 128                 gfs2_assert(sdp, bd->bd_ail == ai);
 129
 130                 if (buffer_busy(bh)) {
 131                         if (flags & DIO_ALL)
 132                                 continue;
 133                         else
 134                                 break;
 135                 }
 136
 137                 if (!buffer_uptodate(bh))
 138                         gfs2_io_error_bh(sdp, bh);
 139
 140                 list_move(&bd->bd_ail_st_list, &ai->ai_ail2_list);
 141         }
 142
 143         return list_empty(&ai->ai_ail1_list);
 144 }
 145
 146 static void gfs2_ail1_start(struct gfs2_sbd *sdp, int flags)
 147 {
 148         struct list_head *head = &sdp->sd_ail1_list;
 149         u64 sync_gen;
 150         struct list_head *first;
 151         struct gfs2_ail *first_ai, *ai, *tmp;
 152         int done = 0;
 153
 154         gfs2_log_lock(sdp);
 155         if (list_empty(head)) {
 156                 gfs2_log_unlock(sdp);
 157                 return;
 158         }
 159         sync_gen = sdp->sd_ail_sync_gen++;
 160
 161         first = head->prev;
 162         first_ai = list_entry(first, struct gfs2_ail, ai_list);
 163         first_ai->ai_sync_gen = sync_gen;
 164         gfs2_ail1_start_one(sdp, first_ai); /* This may drop log lock */
 165
 166         if (flags & DIO_ALL)
 167                 first = NULL;
 168
 169         while(!done) {
 170                 if (first && (head->prev != first ||
 171                               gfs2_ail1_empty_one(sdp, first_ai, 0)))
 172                         break;
 173
 174                 done = 1;
 175                 list_for_each_entry_safe_reverse(ai, tmp, head, ai_list) {
 176                         if (ai->ai_sync_gen >= sync_gen)
 177                                 continue;
 178                         ai->ai_sync_gen = sync_gen;
 179                         gfs2_ail1_start_one(sdp, ai); /* This may drop log lock */
 180                         done = 0;
 181                         break;
 182                 }
 183         }
 184
 185         gfs2_log_unlock(sdp);
 186 }
 187
 188 int gfs2_ail1_empty(struct gfs2_sbd *sdp, int flags)
 189 {
 190         struct gfs2_ail *ai, *s;
 191         int ret;
 192
 193         gfs2_log_lock(sdp);
 194
 195         list_for_each_entry_safe_reverse(ai, s, &sdp->sd_ail1_list, ai_list) {
 196                 if (gfs2_ail1_empty_one(sdp, ai, flags))
 197                         list_move(&ai->ai_list, &sdp->sd_ail2_list);
 198                 else if (!(flags & DIO_ALL))
 199                         break;
 200         }
 201
 202         ret = list_empty(&sdp->sd_ail1_list);
 203
 204         gfs2_log_unlock(sdp);
 205
 206         return ret;
 207 }
 208
 209
 210 /**
 211  * gfs2_ail2_empty_one - Check whether or not a trans in the AIL has been synced
 212  * @sdp: the filesystem
 213  * @ai: the AIL entry
 214  *
 215  */
 216
 217 static void gfs2_ail2_empty_one(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
 218 {
 219         struct list_head *head = &ai->ai_ail2_list;
 220         struct gfs2_bufdata *bd;
 221
 222         while (!list_empty(head)) {
 223                 bd = list_entry(head->prev, struct gfs2_bufdata,
 224                                 bd_ail_st_list);
 225                 gfs2_assert(sdp, bd->bd_ail == ai);
 226                 bd->bd_ail = NULL;
 227                 list_del(&bd->bd_ail_st_list);
 228                 list_del(&bd->bd_ail_gl_list);
 229                 atomic_dec(&bd->bd_gl->gl_ail_count);
 230                 brelse(bd->bd_bh);
 231         }
 232 }
 233
 234 static void ail2_empty(struct gfs2_sbd *sdp, unsigned int new_tail)
 235 {
 236         struct gfs2_ail *ai, *safe;
 237         unsigned int old_tail = sdp->sd_log_tail;
 238         int wrap = (new_tail < old_tail);
 239         int a, b, rm;
 240
 241         gfs2_log_lock(sdp);
 242
 243         list_for_each_entry_safe(ai, safe, &sdp->sd_ail2_list, ai_list) {
 244                 a = (old_tail <= ai->ai_first);
 245                 b = (ai->ai_first < new_tail);
 246                 rm = (wrap) ? (a || b) : (a && b);
 247                 if (!rm)
 248                         continue;
 249
 250                 gfs2_ail2_empty_one(sdp, ai);
 251                 list_del(&ai->ai_list);
 252                 gfs2_assert_warn(sdp, list_empty(&ai->ai_ail1_list));
 253                 gfs2_assert_warn(sdp, list_empty(&ai->ai_ail2_list));
 254                 kfree(ai);
 255         }
 256
 257         gfs2_log_unlock(sdp);
 258 }
 259
 260 /**
 261  * gfs2_log_reserve - Make a log reservation
 262  * @sdp: The GFS2 superblock
 263  * @blks: The number of blocks to reserve
 264  *
 265  * Note that we never give out the last few blocks of the journal. Thats
 266  * due to the fact that there is are a small number of header blocks
 267  * associated with each log flush. The exact number can't be known until
 268  * flush time, so we ensure that we have just enough free blocks at all
 269  * times to avoid running out during a log flush.
 270  *
 271  * Returns: errno
 272  */
 273
 274 int gfs2_log_reserve(struct gfs2_sbd *sdp, unsigned int blks)
 275 {
 276         unsigned int try = 0;
 277         unsigned reserved_blks = 6 * (4096 / sdp->sd_vfs->s_blocksize);
 278
 279         if (gfs2_assert_warn(sdp, blks) ||
 280             gfs2_assert_warn(sdp, blks <= sdp->sd_jdesc->jd_blocks))
 281                 return -EINVAL;
 282
 283         mutex_lock(&sdp->sd_log_reserve_mutex);
 284         gfs2_log_lock(sdp);
 285         while(sdp->sd_log_blks_free <= (blks + reserved_blks)) {
 286                 gfs2_log_unlock(sdp);
 287                 gfs2_ail1_empty(sdp, 0);
 288                 gfs2_log_flush(sdp, NULL);
 289
 290                 if (try++)
 291                         gfs2_ail1_start(sdp, 0);
 292                 gfs2_log_lock(sdp);
 293         }
 294         sdp->sd_log_blks_free -= blks;
 295         gfs2_log_unlock(sdp);
 296         mutex_unlock(&sdp->sd_log_reserve_mutex);
 297
 298         down_read(&sdp->sd_log_flush_lock);
 299
 300         return 0;
 301 }
 302
 303 /**
 304  * gfs2_log_release - Release a given number of log blocks
 305  * @sdp: The GFS2 superblock
 306  * @blks: The number of blocks
 307  *
 308  */
 309
 310 void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks)
 311 {
 312
 313         gfs2_log_lock(sdp);
 314         sdp->sd_log_blks_free += blks;
 315         gfs2_assert_withdraw(sdp,
 316                              sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks);
 317         gfs2_log_unlock(sdp);
 318         up_read(&sdp->sd_log_flush_lock);
 319 }
 320
 321 static u64 log_bmap(struct gfs2_sbd *sdp, unsigned int lbn)
 322 {
 323         struct inode *inode = sdp->sd_jdesc->jd_inode;
 324         int error;
 325         struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
 326
 327         bh_map.b_size = 1 << inode->i_blkbits;
 328         error = gfs2_block_map(inode, lbn, 0, &bh_map);
 329         if (error || !bh_map.b_blocknr)
 330                 printk(KERN_INFO "error=%d, dbn=%llu lbn=%u", error,
 331                        (unsigned long long)bh_map.b_blocknr, lbn);
 332         gfs2_assert_withdraw(sdp, !error && bh_map.b_blocknr);
 333
 334         return bh_map.b_blocknr;
 335 }
 336
 337 /**
 338  * log_distance - Compute distance between two journal blocks
 339  * @sdp: The GFS2 superblock
 340  * @newer: The most recent journal block of the pair
 341  * @older: The older journal block of the pair
 342  *
 343  *   Compute the distance (in the journal direction) between two
 344  *   blocks in the journal
 345  *
 346  * Returns: the distance in blocks
 347  */
 348
 349 static inline unsigned int log_distance(struct gfs2_sbd *sdp, unsigned int newer,
 350                                         unsigned int older)
 351 {
 352         int dist;
 353
 354         dist = newer - older;
 355         if (dist < 0)
 356                 dist += sdp->sd_jdesc->jd_blocks;
 357
 358         return dist;
 359 }
 360
 361 static unsigned int current_tail(struct gfs2_sbd *sdp)
 362 {
 363         struct gfs2_ail *ai;
 364         unsigned int tail;
 365
 366         gfs2_log_lock(sdp);
 367
 368         if (list_empty(&sdp->sd_ail1_list)) {
 369                 tail = sdp->sd_log_head;
 370         } else {
 371                 ai = list_entry(sdp->sd_ail1_list.prev, struct gfs2_ail, ai_list);
 372                 tail = ai->ai_first;
 373         }
 374
 375         gfs2_log_unlock(sdp);
 376
 377         return tail;
 378 }
 379
 380 static inline void log_incr_head(struct gfs2_sbd *sdp)
 381 {
 382         if (sdp->sd_log_flush_head == sdp->sd_log_tail)
 383                 gfs2_assert_withdraw(sdp, sdp->sd_log_flush_head == sdp->sd_log_head);
 384
 385         if (++sdp->sd_log_flush_head == sdp->sd_jdesc->jd_blocks) {
 386                 sdp->sd_log_flush_head = 0;
 387                 sdp->sd_log_flush_wrapped = 1;
 388         }
 389 }
 390
 391 /**
 392  * gfs2_log_get_buf - Get and initialize a buffer to use for log control data
 393  * @sdp: The GFS2 superblock
 394  *
 395  * Returns: the buffer_head
 396  */
 397
 398 struct buffer_head *gfs2_log_get_buf(struct gfs2_sbd *sdp)
 399 {
 400         u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head);
 401         struct gfs2_log_buf *lb;
 402         struct buffer_head *bh;
 403
 404         lb = kzalloc(sizeof(struct gfs2_log_buf), GFP_NOFS | __GFP_NOFAIL);
 405         list_add(&lb->lb_list, &sdp->sd_log_flush_list);
 406
 407         bh = lb->lb_bh = sb_getblk(sdp->sd_vfs, blkno);
 408         lock_buffer(bh);
 409         memset(bh->b_data, 0, bh->b_size);
 410         set_buffer_uptodate(bh);
 411         clear_buffer_dirty(bh);
 412         unlock_buffer(bh);
 413
 414         log_incr_head(sdp);
 415
 416         return bh;
 417 }
 418
 419 /**
 420  * gfs2_log_fake_buf - Build a fake buffer head to write metadata buffer to log
 421  * @sdp: the filesystem
 422  * @data: the data the buffer_head should point to
 423  *
 424  * Returns: the log buffer descriptor
 425  */
 426
 427 struct buffer_head *gfs2_log_fake_buf(struct gfs2_sbd *sdp,
 428                                       struct buffer_head *real)
 429 {
 430         u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head);
 431         struct gfs2_log_buf *lb;
 432         struct buffer_head *bh;
 433
 434         lb = kzalloc(sizeof(struct gfs2_log_buf), GFP_NOFS | __GFP_NOFAIL);
 435         list_add(&lb->lb_list, &sdp->sd_log_flush_list);
 436         lb->lb_real = real;
 437
 438         bh = lb->lb_bh = alloc_buffer_head(GFP_NOFS | __GFP_NOFAIL);
 439         atomic_set(&bh->b_count, 1);
 440         bh->b_state = (1 << BH_Mapped) | (1 << BH_Uptodate);
 441         set_bh_page(bh, real->b_page, bh_offset(real));
 442         bh->b_blocknr = blkno;
 443         bh->b_size = sdp->sd_sb.sb_bsize;
 444         bh->b_bdev = sdp->sd_vfs->s_bdev;
 445
 446         log_incr_head(sdp);
 447
 448         return bh;
 449 }
 450
 451 static void log_pull_tail(struct gfs2_sbd *sdp, unsigned int new_tail, int pull)
 452 {
 453         unsigned int dist = log_distance(sdp, new_tail, sdp->sd_log_tail);
 454
 455         ail2_empty(sdp, new_tail);
 456
 457         gfs2_log_lock(sdp);
 458         sdp->sd_log_blks_free += dist - (pull ? 1 : 0);
 459         gfs2_assert_withdraw(sdp, sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks);
 460         gfs2_log_unlock(sdp);
 461
 462         sdp->sd_log_tail = new_tail;
 463 }
 464
 465 /**
 466  * log_write_header - Get and initialize a journal header buffer
 467  * @sdp: The GFS2 superblock
 468  *
 469  * Returns: the initialized log buffer descriptor
 470  */
 471
 472 static void log_write_header(struct gfs2_sbd *sdp, u32 flags, int pull)
 473 {
 474         u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head);
 475         struct buffer_head *bh;
 476         struct gfs2_log_header *lh;
 477         unsigned int tail;
 478         u32 hash;
 479
 480         bh = sb_getblk(sdp->sd_vfs, blkno);
 481         lock_buffer(bh);
 482         memset(bh->b_data, 0, bh->b_size);
 483         set_buffer_uptodate(bh);
 484         clear_buffer_dirty(bh);
 485         unlock_buffer(bh);
 486
 487         gfs2_ail1_empty(sdp, 0);
 488         tail = current_tail(sdp);
 489
 490         lh = (struct gfs2_log_header *)bh->b_data;
 491         memset(lh, 0, sizeof(struct gfs2_log_header));
 492         lh->lh_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
 493         lh->lh_header.mh_type = cpu_to_be32(GFS2_METATYPE_LH);
 494         lh->lh_header.mh_format = cpu_to_be32(GFS2_FORMAT_LH);
 495         lh->lh_sequence = cpu_to_be64(sdp->sd_log_sequence++);
 496         lh->lh_flags = cpu_to_be32(flags);
 497         lh->lh_tail = cpu_to_be32(tail);
 498         lh->lh_blkno = cpu_to_be32(sdp->sd_log_flush_head);
 499         hash = gfs2_disk_hash(bh->b_data, sizeof(struct gfs2_log_header));
 500         lh->lh_hash = cpu_to_be32(hash);
 501
 502         set_buffer_dirty(bh);
 503         if (sync_dirty_buffer(bh))
 504                 gfs2_io_error_bh(sdp, bh);
 505         brelse(bh);
 506
 507         if (sdp->sd_log_tail != tail)
 508                 log_pull_tail(sdp, tail, pull);
 509         else
 510                 gfs2_assert_withdraw(sdp, !pull);
 511
 512         sdp->sd_log_idle = (tail == sdp->sd_log_flush_head);
 513         log_incr_head(sdp);
 514 }
 515
 516 static void log_flush_commit(struct gfs2_sbd *sdp)
 517 {
 518         struct list_head *head = &sdp->sd_log_flush_list;
 519         struct gfs2_log_buf *lb;
 520         struct buffer_head *bh;
 521
 522         while (!list_empty(head)) {
 523                 lb = list_entry(head->next, struct gfs2_log_buf, lb_list);
 524                 list_del(&lb->lb_list);
 525                 bh = lb->lb_bh;
 526
 527                 wait_on_buffer(bh);
 528                 if (!buffer_uptodate(bh))
 529                         gfs2_io_error_bh(sdp, bh);
 530                 if (lb->lb_real) {
 531                         while (atomic_read(&bh->b_count) != 1)  /* Grrrr... */
 532                                 schedule();
 533                         free_buffer_head(bh);
 534                 } else
 535                         brelse(bh);
 536                 kfree(lb);
 537         }
 538
 539         log_write_header(sdp, 0, 0);
 540 }
 541
 542 /**
 543  * gfs2_log_flush - flush incore transaction(s)
 544  * @sdp: the filesystem
 545  * @gl: The glock structure to flush.  If NULL, flush the whole incore log
 546  *
 547  */
 548
 549 void gfs2_log_flush(struct gfs2_sbd *sdp, struct gfs2_glock *gl)
 550 {
 551         struct gfs2_ail *ai;
 552
 553         down_write(&sdp->sd_log_flush_lock);
 554
 555         if (gl) {
 556                 gfs2_log_lock(sdp);
 557                 if (list_empty(&gl->gl_le.le_list)) {
 558                         gfs2_log_unlock(sdp);
 559                         up_write(&sdp->sd_log_flush_lock);
 560                         return;
 561                 }
 562                 gfs2_log_unlock(sdp);
 563         }
 564
 565         ai = kzalloc(sizeof(struct gfs2_ail), GFP_NOFS | __GFP_NOFAIL);
 566         INIT_LIST_HEAD(&ai->ai_ail1_list);
 567         INIT_LIST_HEAD(&ai->ai_ail2_list);
 568
 569         gfs2_assert_withdraw(sdp, sdp->sd_log_num_buf == sdp->sd_log_commited_buf);
 570         gfs2_assert_withdraw(sdp,
 571                         sdp->sd_log_num_revoke == sdp->sd_log_commited_revoke);
 572
 573         sdp->sd_log_flush_head = sdp->sd_log_head;
 574         sdp->sd_log_flush_wrapped = 0;
 575         ai->ai_first = sdp->sd_log_flush_head;
 576
 577         lops_before_commit(sdp);
 578         if (!list_empty(&sdp->sd_log_flush_list))
 579                 log_flush_commit(sdp);
 580         else if (sdp->sd_log_tail != current_tail(sdp) && !sdp->sd_log_idle)
 581                 log_write_header(sdp, 0, PULL);
 582         lops_after_commit(sdp, ai);
 583
 584         gfs2_log_lock(sdp);
 585         sdp->sd_log_head = sdp->sd_log_flush_head;
 586         sdp->sd_log_blks_free -= sdp->sd_log_num_hdrs;
 587         sdp->sd_log_blks_reserved = 0;
 588         sdp->sd_log_commited_buf = 0;
 589         sdp->sd_log_num_hdrs = 0;
 590         sdp->sd_log_commited_revoke = 0;
 591
 592         if (!list_empty(&ai->ai_ail1_list)) {
 593                 list_add(&ai->ai_list, &sdp->sd_ail1_list);
 594                 ai = NULL;
 595         }
 596         gfs2_log_unlock(sdp);
 597
 598         sdp->sd_vfs->s_dirt = 0;
 599         up_write(&sdp->sd_log_flush_lock);
 600
 601         kfree(ai);
 602 }
 603
 604 static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
 605 {
 606         unsigned int reserved = 0;
 607         unsigned int old;
 608
 609         gfs2_log_lock(sdp);
 610
 611         sdp->sd_log_commited_buf += tr->tr_num_buf_new - tr->tr_num_buf_rm;
 612         gfs2_assert_withdraw(sdp, ((int)sdp->sd_log_commited_buf) >= 0);
 613         sdp->sd_log_commited_revoke += tr->tr_num_revoke - tr->tr_num_revoke_rm;
 614         gfs2_assert_withdraw(sdp, ((int)sdp->sd_log_commited_revoke) >= 0);
 615
 616         if (sdp->sd_log_commited_buf)
 617                 reserved += sdp->sd_log_commited_buf;
 618         if (sdp->sd_log_commited_revoke)
 619                 reserved += gfs2_struct2blk(sdp, sdp->sd_log_commited_revoke,
 620                                             sizeof(u64));
 621         if (reserved)
 622                 reserved++;
 623
 624         old = sdp->sd_log_blks_free;
 625         sdp->sd_log_blks_free += tr->tr_reserved -
 626                                  (reserved - sdp->sd_log_blks_reserved);
 627
 628         gfs2_assert_withdraw(sdp, sdp->sd_log_blks_free >= old);
 629         gfs2_assert_withdraw(sdp,
 630                              sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks +
 631                              sdp->sd_log_num_hdrs);
 632
 633         sdp->sd_log_blks_reserved = reserved;
 634
 635         gfs2_log_unlock(sdp);
 636 }
 637
 638 /**
 639  * gfs2_log_commit - Commit a transaction to the log
 640  * @sdp: the filesystem
 641  * @tr: the transaction
 642  *
 643  * Returns: errno
 644  */
 645
 646 void gfs2_log_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
 647 {
 648         log_refund(sdp, tr);
 649         lops_incore_commit(sdp, tr);
 650
 651         sdp->sd_vfs->s_dirt = 1;
 652         up_read(&sdp->sd_log_flush_lock);
 653
 654         gfs2_log_lock(sdp);
 655         if (sdp->sd_log_num_buf > gfs2_tune_get(sdp, gt_incore_log_blocks))
 656                 wake_up_process(sdp->sd_logd_process);
 657         gfs2_log_unlock(sdp);
 658 }
 659
 660 /**
 661  * gfs2_log_shutdown - write a shutdown header into a journal
 662  * @sdp: the filesystem
 663  *
 664  */
 665
 666 void gfs2_log_shutdown(struct gfs2_sbd *sdp)
 667 {
 668         down_write(&sdp->sd_log_flush_lock);
 669
 670         gfs2_assert_withdraw(sdp, !sdp->sd_log_blks_reserved);
 671         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_gl);
 672         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_buf);
 673         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_jdata);
 674         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
 675         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_rg);
 676         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_databuf);
 677         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_hdrs);
 678         gfs2_assert_withdraw(sdp, list_empty(&sdp->sd_ail1_list));
 679
 680         sdp->sd_log_flush_head = sdp->sd_log_head;
 681         sdp->sd_log_flush_wrapped = 0;
 682
 683         log_write_header(sdp, GFS2_LOG_HEAD_UNMOUNT, 0);
 684
 685         gfs2_assert_warn(sdp, sdp->sd_log_blks_free == sdp->sd_jdesc->jd_blocks);
 686         gfs2_assert_warn(sdp, sdp->sd_log_head == sdp->sd_log_tail);
 687         gfs2_assert_warn(sdp, list_empty(&sdp->sd_ail2_list));
 688
 689         sdp->sd_log_head = sdp->sd_log_flush_head;
 690         sdp->sd_log_tail = sdp->sd_log_head;
 691
 692         up_write(&sdp->sd_log_flush_lock);
 693 }
 694
 695
 696 /**
 697  * gfs2_meta_syncfs - sync all the buffers in a filesystem
 698  * @sdp: the filesystem
 699  *
 700  */
 701
 702 void gfs2_meta_syncfs(struct gfs2_sbd *sdp)
 703 {
 704         gfs2_log_flush(sdp, NULL);
 705         for (;;) {
 706                 gfs2_ail1_start(sdp, DIO_ALL);
 707                 if (gfs2_ail1_empty(sdp, DIO_ALL))
 708                         break;
 709                 msleep(10);
 710         }
 711 }
 712