git.oblomov.eu Git - linux-2.6/blob - 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 6 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
 278         if (gfs2_assert_warn(sdp, blks) ||
 279             gfs2_assert_warn(sdp, blks <= sdp->sd_jdesc->jd_blocks))
 280                 return -EINVAL;
 281
 282         mutex_lock(&sdp->sd_log_reserve_mutex);
 283         gfs2_log_lock(sdp);
 284         while(sdp->sd_log_blks_free <= (blks + 6)) {
 285                 gfs2_log_unlock(sdp);
 286                 gfs2_ail1_empty(sdp, 0);
 287                 gfs2_log_flush(sdp, NULL);
 288
 289                 if (try++)
 290                         gfs2_ail1_start(sdp, 0);
 291                 gfs2_log_lock(sdp);
 292         }
 293         sdp->sd_log_blks_free -= blks;
 294         gfs2_log_unlock(sdp);
 295         mutex_unlock(&sdp->sd_log_reserve_mutex);
 296
 297         down_read(&sdp->sd_log_flush_lock);
 298
 299         return 0;
 300 }
 301
 302 /**
 303  * gfs2_log_release - Release a given number of log blocks
 304  * @sdp: The GFS2 superblock
 305  * @blks: The number of blocks
 306  *
 307  */
 308
 309 void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks)
 310 {
 311
 312         gfs2_log_lock(sdp);
 313         sdp->sd_log_blks_free += blks;
 314         gfs2_assert_withdraw(sdp,
 315                              sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks);
 316         gfs2_log_unlock(sdp);
 317         up_read(&sdp->sd_log_flush_lock);
 318 }
 319
 320 static u64 log_bmap(struct gfs2_sbd *sdp, unsigned int lbn)
 321 {
 322         struct inode *inode = sdp->sd_jdesc->jd_inode;
 323         int error;
 324         struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
 325
 326         bh_map.b_size = 1 << inode->i_blkbits;
 327         error = gfs2_block_map(inode, lbn, 0, &bh_map);
 328         if (error || !bh_map.b_blocknr)
 329                 printk(KERN_INFO "error=%d, dbn=%llu lbn=%u", error,
 330                        (unsigned long long)bh_map.b_blocknr, lbn);
 331         gfs2_assert_withdraw(sdp, !error && bh_map.b_blocknr);
 332
 333         return bh_map.b_blocknr;
 334 }
 335
 336 /**
 337  * log_distance - Compute distance between two journal blocks
 338  * @sdp: The GFS2 superblock
 339  * @newer: The most recent journal block of the pair
 340  * @older: The older journal block of the pair
 341  *
 342  *   Compute the distance (in the journal direction) between two
 343  *   blocks in the journal
 344  *
 345  * Returns: the distance in blocks
 346  */
 347
 348 static inline unsigned int log_distance(struct gfs2_sbd *sdp, unsigned int newer,
 349                                         unsigned int older)
 350 {
 351         int dist;
 352
 353         dist = newer - older;
 354         if (dist < 0)
 355                 dist += sdp->sd_jdesc->jd_blocks;
 356
 357         return dist;
 358 }
 359
 360 static unsigned int current_tail(struct gfs2_sbd *sdp)
 361 {
 362         struct gfs2_ail *ai;
 363         unsigned int tail;
 364
 365         gfs2_log_lock(sdp);
 366
 367         if (list_empty(&sdp->sd_ail1_list)) {
 368                 tail = sdp->sd_log_head;
 369         } else {
 370                 ai = list_entry(sdp->sd_ail1_list.prev, struct gfs2_ail, ai_list);
 371                 tail = ai->ai_first;
 372         }
 373
 374         gfs2_log_unlock(sdp);
 375
 376         return tail;
 377 }
 378
 379 static inline void log_incr_head(struct gfs2_sbd *sdp)
 380 {
 381         if (sdp->sd_log_flush_head == sdp->sd_log_tail)
 382                 gfs2_assert_withdraw(sdp, sdp->sd_log_flush_head == sdp->sd_log_head);
 383
 384         if (++sdp->sd_log_flush_head == sdp->sd_jdesc->jd_blocks) {
 385                 sdp->sd_log_flush_head = 0;
 386                 sdp->sd_log_flush_wrapped = 1;
 387         }
 388 }
 389
 390 /**
 391  * gfs2_log_get_buf - Get and initialize a buffer to use for log control data
 392  * @sdp: The GFS2 superblock
 393  *
 394  * Returns: the buffer_head
 395  */
 396
 397 struct buffer_head *gfs2_log_get_buf(struct gfs2_sbd *sdp)
 398 {
 399         u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head);
 400         struct gfs2_log_buf *lb;
 401         struct buffer_head *bh;
 402
 403         lb = kzalloc(sizeof(struct gfs2_log_buf), GFP_NOFS | __GFP_NOFAIL);
 404         list_add(&lb->lb_list, &sdp->sd_log_flush_list);
 405
 406         bh = lb->lb_bh = sb_getblk(sdp->sd_vfs, blkno);
 407         lock_buffer(bh);
 408         memset(bh->b_data, 0, bh->b_size);
 409         set_buffer_uptodate(bh);
 410         clear_buffer_dirty(bh);
 411         unlock_buffer(bh);
 412
 413         log_incr_head(sdp);
 414
 415         return bh;
 416 }
 417
 418 /**
 419  * gfs2_log_fake_buf - Build a fake buffer head to write metadata buffer to log
 420  * @sdp: the filesystem
 421  * @data: the data the buffer_head should point to
 422  *
 423  * Returns: the log buffer descriptor
 424  */
 425
 426 struct buffer_head *gfs2_log_fake_buf(struct gfs2_sbd *sdp,
 427                                       struct buffer_head *real)
 428 {
 429         u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head);
 430         struct gfs2_log_buf *lb;
 431         struct buffer_head *bh;
 432
 433         lb = kzalloc(sizeof(struct gfs2_log_buf), GFP_NOFS | __GFP_NOFAIL);
 434         list_add(&lb->lb_list, &sdp->sd_log_flush_list);
 435         lb->lb_real = real;
 436
 437         bh = lb->lb_bh = alloc_buffer_head(GFP_NOFS | __GFP_NOFAIL);
 438         atomic_set(&bh->b_count, 1);
 439         bh->b_state = (1 << BH_Mapped) | (1 << BH_Uptodate);
 440         set_bh_page(bh, real->b_page, bh_offset(real));
 441         bh->b_blocknr = blkno;
 442         bh->b_size = sdp->sd_sb.sb_bsize;
 443         bh->b_bdev = sdp->sd_vfs->s_bdev;
 444
 445         log_incr_head(sdp);
 446
 447         return bh;
 448 }
 449
 450 static void log_pull_tail(struct gfs2_sbd *sdp, unsigned int new_tail, int pull)
 451 {
 452         unsigned int dist = log_distance(sdp, new_tail, sdp->sd_log_tail);
 453
 454         ail2_empty(sdp, new_tail);
 455
 456         gfs2_log_lock(sdp);
 457         sdp->sd_log_blks_free += dist - (pull ? 1 : 0);
 458         gfs2_assert_withdraw(sdp, sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks);
 459         gfs2_log_unlock(sdp);
 460
 461         sdp->sd_log_tail = new_tail;
 462 }
 463
 464 /**
 465  * log_write_header - Get and initialize a journal header buffer
 466  * @sdp: The GFS2 superblock
 467  *
 468  * Returns: the initialized log buffer descriptor
 469  */
 470
 471 static void log_write_header(struct gfs2_sbd *sdp, u32 flags, int pull)
 472 {
 473         u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head);
 474         struct buffer_head *bh;
 475         struct gfs2_log_header *lh;
 476         unsigned int tail;
 477         u32 hash;
 478
 479         bh = sb_getblk(sdp->sd_vfs, blkno);
 480         lock_buffer(bh);
 481         memset(bh->b_data, 0, bh->b_size);
 482         set_buffer_uptodate(bh);
 483         clear_buffer_dirty(bh);
 484         unlock_buffer(bh);
 485
 486         gfs2_ail1_empty(sdp, 0);
 487         tail = current_tail(sdp);
 488
 489         lh = (struct gfs2_log_header *)bh->b_data;
 490         memset(lh, 0, sizeof(struct gfs2_log_header));
 491         lh->lh_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
 492         lh->lh_header.mh_type = cpu_to_be32(GFS2_METATYPE_LH);
 493         lh->lh_header.mh_format = cpu_to_be32(GFS2_FORMAT_LH);
 494         lh->lh_sequence = cpu_to_be64(sdp->sd_log_sequence++);
 495         lh->lh_flags = cpu_to_be32(flags);
 496         lh->lh_tail = cpu_to_be32(tail);
 497         lh->lh_blkno = cpu_to_be32(sdp->sd_log_flush_head);
 498         hash = gfs2_disk_hash(bh->b_data, sizeof(struct gfs2_log_header));
 499         lh->lh_hash = cpu_to_be32(hash);
 500
 501         set_buffer_dirty(bh);
 502         if (sync_dirty_buffer(bh))
 503                 gfs2_io_error_bh(sdp, bh);
 504         brelse(bh);
 505
 506         if (sdp->sd_log_tail != tail)
 507                 log_pull_tail(sdp, tail, pull);
 508         else
 509                 gfs2_assert_withdraw(sdp, !pull);
 510
 511         sdp->sd_log_idle = (tail == sdp->sd_log_flush_head);
 512         log_incr_head(sdp);
 513 }
 514
 515 static void log_flush_commit(struct gfs2_sbd *sdp)
 516 {
 517         struct list_head *head = &sdp->sd_log_flush_list;
 518         struct gfs2_log_buf *lb;
 519         struct buffer_head *bh;
 520
 521         while (!list_empty(head)) {
 522                 lb = list_entry(head->next, struct gfs2_log_buf, lb_list);
 523                 list_del(&lb->lb_list);
 524                 bh = lb->lb_bh;
 525
 526                 wait_on_buffer(bh);
 527                 if (!buffer_uptodate(bh))
 528                         gfs2_io_error_bh(sdp, bh);
 529                 if (lb->lb_real) {
 530                         while (atomic_read(&bh->b_count) != 1)  /* Grrrr... */
 531                                 schedule();
 532                         free_buffer_head(bh);
 533                 } else
 534                         brelse(bh);
 535                 kfree(lb);
 536         }
 537
 538         log_write_header(sdp, 0, 0);
 539 }
 540
 541 /**
 542  * gfs2_log_flush - flush incore transaction(s)
 543  * @sdp: the filesystem
 544  * @gl: The glock structure to flush.  If NULL, flush the whole incore log
 545  *
 546  */
 547
 548 void gfs2_log_flush(struct gfs2_sbd *sdp, struct gfs2_glock *gl)
 549 {
 550         struct gfs2_ail *ai;
 551
 552         down_write(&sdp->sd_log_flush_lock);
 553
 554         if (gl) {
 555                 gfs2_log_lock(sdp);
 556                 if (list_empty(&gl->gl_le.le_list)) {
 557                         gfs2_log_unlock(sdp);
 558                         up_write(&sdp->sd_log_flush_lock);
 559                         return;
 560                 }
 561                 gfs2_log_unlock(sdp);
 562         }
 563
 564         ai = kzalloc(sizeof(struct gfs2_ail), GFP_NOFS | __GFP_NOFAIL);
 565         INIT_LIST_HEAD(&ai->ai_ail1_list);
 566         INIT_LIST_HEAD(&ai->ai_ail2_list);
 567
 568         gfs2_assert_withdraw(sdp, sdp->sd_log_num_buf == sdp->sd_log_commited_buf);
 569         gfs2_assert_withdraw(sdp,
 570                         sdp->sd_log_num_revoke == sdp->sd_log_commited_revoke);
 571
 572         sdp->sd_log_flush_head = sdp->sd_log_head;
 573         sdp->sd_log_flush_wrapped = 0;
 574         ai->ai_first = sdp->sd_log_flush_head;
 575
 576         lops_before_commit(sdp);
 577         if (!list_empty(&sdp->sd_log_flush_list))
 578                 log_flush_commit(sdp);
 579         else if (sdp->sd_log_tail != current_tail(sdp) && !sdp->sd_log_idle)
 580                 log_write_header(sdp, 0, PULL);
 581         lops_after_commit(sdp, ai);
 582
 583         gfs2_log_lock(sdp);
 584         sdp->sd_log_head = sdp->sd_log_flush_head;
 585         sdp->sd_log_blks_free -= sdp->sd_log_num_hdrs;
 586         sdp->sd_log_blks_reserved = 0;
 587         sdp->sd_log_commited_buf = 0;
 588         sdp->sd_log_num_hdrs = 0;
 589         sdp->sd_log_commited_revoke = 0;
 590
 591         if (!list_empty(&ai->ai_ail1_list)) {
 592                 list_add(&ai->ai_list, &sdp->sd_ail1_list);
 593                 ai = NULL;
 594         }
 595         gfs2_log_unlock(sdp);
 596
 597         sdp->sd_vfs->s_dirt = 0;
 598         up_write(&sdp->sd_log_flush_lock);
 599
 600         kfree(ai);
 601 }
 602
 603 static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
 604 {
 605         unsigned int reserved = 0;
 606         unsigned int old;
 607
 608         gfs2_log_lock(sdp);
 609
 610         sdp->sd_log_commited_buf += tr->tr_num_buf_new - tr->tr_num_buf_rm;
 611         gfs2_assert_withdraw(sdp, ((int)sdp->sd_log_commited_buf) >= 0);
 612         sdp->sd_log_commited_revoke += tr->tr_num_revoke - tr->tr_num_revoke_rm;
 613         gfs2_assert_withdraw(sdp, ((int)sdp->sd_log_commited_revoke) >= 0);
 614
 615         if (sdp->sd_log_commited_buf)
 616                 reserved += sdp->sd_log_commited_buf;
 617         if (sdp->sd_log_commited_revoke)
 618                 reserved += gfs2_struct2blk(sdp, sdp->sd_log_commited_revoke,
 619                                             sizeof(u64));
 620         if (reserved)
 621                 reserved++;
 622
 623         old = sdp->sd_log_blks_free;
 624         sdp->sd_log_blks_free += tr->tr_reserved -
 625                                  (reserved - sdp->sd_log_blks_reserved);
 626
 627         gfs2_assert_withdraw(sdp, sdp->sd_log_blks_free >= old);
 628         gfs2_assert_withdraw(sdp,
 629                              sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks +
 630                              sdp->sd_log_num_hdrs);
 631
 632         sdp->sd_log_blks_reserved = reserved;
 633
 634         gfs2_log_unlock(sdp);
 635 }
 636
 637 /**
 638  * gfs2_log_commit - Commit a transaction to the log
 639  * @sdp: the filesystem
 640  * @tr: the transaction
 641  *
 642  * Returns: errno
 643  */
 644
 645 void gfs2_log_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
 646 {
 647         log_refund(sdp, tr);
 648         lops_incore_commit(sdp, tr);
 649
 650         sdp->sd_vfs->s_dirt = 1;
 651         up_read(&sdp->sd_log_flush_lock);
 652
 653         gfs2_log_lock(sdp);
 654         if (sdp->sd_log_num_buf > gfs2_tune_get(sdp, gt_incore_log_blocks))
 655                 wake_up_process(sdp->sd_logd_process);
 656         gfs2_log_unlock(sdp);
 657 }
 658
 659 /**
 660  * gfs2_log_shutdown - write a shutdown header into a journal
 661  * @sdp: the filesystem
 662  *
 663  */
 664
 665 void gfs2_log_shutdown(struct gfs2_sbd *sdp)
 666 {
 667         down_write(&sdp->sd_log_flush_lock);
 668
 669         gfs2_assert_withdraw(sdp, !sdp->sd_log_blks_reserved);
 670         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_gl);
 671         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_buf);
 672         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_jdata);
 673         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
 674         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_rg);
 675         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_databuf);
 676         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_hdrs);
 677         gfs2_assert_withdraw(sdp, list_empty(&sdp->sd_ail1_list));
 678
 679         sdp->sd_log_flush_head = sdp->sd_log_head;
 680         sdp->sd_log_flush_wrapped = 0;
 681
 682         log_write_header(sdp, GFS2_LOG_HEAD_UNMOUNT, 0);
 683
 684         gfs2_assert_warn(sdp, sdp->sd_log_blks_free == sdp->sd_jdesc->jd_blocks);
 685         gfs2_assert_warn(sdp, sdp->sd_log_head == sdp->sd_log_tail);
 686         gfs2_assert_warn(sdp, list_empty(&sdp->sd_ail2_list));
 687
 688         sdp->sd_log_head = sdp->sd_log_flush_head;
 689         sdp->sd_log_tail = sdp->sd_log_head;
 690
 691         up_write(&sdp->sd_log_flush_lock);
 692 }
 693
 694
 695 /**
 696  * gfs2_meta_syncfs - sync all the buffers in a filesystem
 697  * @sdp: the filesystem
 698  *
 699  */
 700
 701 void gfs2_meta_syncfs(struct gfs2_sbd *sdp)
 702 {
 703         gfs2_log_flush(sdp, NULL);
 704         for (;;) {
 705                 gfs2_ail1_start(sdp, DIO_ALL);
 706                 if (gfs2_ail1_empty(sdp, DIO_ALL))
 707                         break;
 708                 msleep(10);
 709         }
 710 }
 711