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