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;
 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         head = &sdp->sd_ail1_list;
 156         if (list_empty(head)) {
 157                 gfs2_log_unlock(sdp);
 158                 return;
 159         }
 160         sync_gen = sdp->sd_ail_sync_gen++;
 161
 162         first = head->prev;
 163         first_ai = list_entry(first, struct gfs2_ail, ai_list);
 164         first_ai->ai_sync_gen = sync_gen;
 165         gfs2_ail1_start_one(sdp, first_ai); /* This may drop log lock */
 166
 167         if (flags & DIO_ALL)
 168                 first = NULL;
 169
 170         while(!done) {
 171                 if (first && (head->prev != first ||
 172                               gfs2_ail1_empty_one(sdp, first_ai, 0)))
 173                         break;
 174
 175                 done = 1;
 176                 list_for_each_entry_safe_reverse(ai, tmp, head, ai_list) {
 177                         if (ai->ai_sync_gen >= sync_gen)
 178                                 continue;
 179                         ai->ai_sync_gen = sync_gen;
 180                         gfs2_ail1_start_one(sdp, ai); /* This may drop log lock */
 181                         done = 0;
 182                         break;
 183                 }
 184         }
 185
 186         gfs2_log_unlock(sdp);
 187 }
 188
 189 int gfs2_ail1_empty(struct gfs2_sbd *sdp, int flags)
 190 {
 191         struct gfs2_ail *ai, *s;
 192         int ret;
 193
 194         gfs2_log_lock(sdp);
 195
 196         list_for_each_entry_safe_reverse(ai, s, &sdp->sd_ail1_list, ai_list) {
 197                 if (gfs2_ail1_empty_one(sdp, ai, flags))
 198                         list_move(&ai->ai_list, &sdp->sd_ail2_list);
 199                 else if (!(flags & DIO_ALL))
 200                         break;
 201         }
 202
 203         ret = list_empty(&sdp->sd_ail1_list);
 204
 205         gfs2_log_unlock(sdp);
 206
 207         return ret;
 208 }
 209
 210
 211 /**
 212  * gfs2_ail2_empty_one - Check whether or not a trans in the AIL has been synced
 213  * @sdp: the filesystem
 214  * @ai: the AIL entry
 215  *
 216  */
 217
 218 static void gfs2_ail2_empty_one(struct gfs2_sbd *sdp, struct gfs2_ail *ai)
 219 {
 220         struct list_head *head = &ai->ai_ail2_list;
 221         struct gfs2_bufdata *bd;
 222         struct gfs2_inode *bh_ip;
 223
 224         while (!list_empty(head)) {
 225                 bd = list_entry(head->prev, struct gfs2_bufdata,
 226                                 bd_ail_st_list);
 227                 gfs2_assert(sdp, bd->bd_ail == ai);
 228                 bd->bd_ail = NULL;
 229                 list_del(&bd->bd_ail_st_list);
 230                 list_del(&bd->bd_ail_gl_list);
 231                 atomic_dec(&bd->bd_gl->gl_ail_count);
 232                 bh_ip = GFS2_I(bd->bd_bh->b_page->mapping->host);
 233                 gfs2_meta_cache_flush(bh_ip);
 234                 brelse(bd->bd_bh);
 235         }
 236 }
 237
 238 static void ail2_empty(struct gfs2_sbd *sdp, unsigned int new_tail)
 239 {
 240         struct gfs2_ail *ai, *safe;
 241         unsigned int old_tail = sdp->sd_log_tail;
 242         int wrap = (new_tail < old_tail);
 243         int a, b, rm;
 244
 245         gfs2_log_lock(sdp);
 246
 247         list_for_each_entry_safe(ai, safe, &sdp->sd_ail2_list, ai_list) {
 248                 a = (old_tail <= ai->ai_first);
 249                 b = (ai->ai_first < new_tail);
 250                 rm = (wrap) ? (a || b) : (a && b);
 251                 if (!rm)
 252                         continue;
 253
 254                 gfs2_ail2_empty_one(sdp, ai);
 255                 list_del(&ai->ai_list);
 256                 gfs2_assert_warn(sdp, list_empty(&ai->ai_ail1_list));
 257                 gfs2_assert_warn(sdp, list_empty(&ai->ai_ail2_list));
 258                 kfree(ai);
 259         }
 260
 261         gfs2_log_unlock(sdp);
 262 }
 263
 264 /**
 265  * gfs2_log_reserve - Make a log reservation
 266  * @sdp: The GFS2 superblock
 267  * @blks: The number of blocks to reserve
 268  *
 269  * Note that we never give out the last few blocks of the journal. Thats
 270  * due to the fact that there is a small number of header blocks
 271  * associated with each log flush. The exact number can't be known until
 272  * flush time, so we ensure that we have just enough free blocks at all
 273  * times to avoid running out during a log flush.
 274  *
 275  * Returns: errno
 276  */
 277
 278 int gfs2_log_reserve(struct gfs2_sbd *sdp, unsigned int blks)
 279 {
 280         unsigned int try = 0;
 281         unsigned reserved_blks = 6 * (4096 / sdp->sd_vfs->s_blocksize);
 282
 283         if (gfs2_assert_warn(sdp, blks) ||
 284             gfs2_assert_warn(sdp, blks <= sdp->sd_jdesc->jd_blocks))
 285                 return -EINVAL;
 286
 287         mutex_lock(&sdp->sd_log_reserve_mutex);
 288         gfs2_log_lock(sdp);
 289         while(sdp->sd_log_blks_free <= (blks + reserved_blks)) {
 290                 gfs2_log_unlock(sdp);
 291                 gfs2_ail1_empty(sdp, 0);
 292                 gfs2_log_flush(sdp, NULL);
 293
 294                 if (try++)
 295                         gfs2_ail1_start(sdp, 0);
 296                 gfs2_log_lock(sdp);
 297         }
 298         sdp->sd_log_blks_free -= blks;
 299         gfs2_log_unlock(sdp);
 300         mutex_unlock(&sdp->sd_log_reserve_mutex);
 301
 302         down_read(&sdp->sd_log_flush_lock);
 303
 304         return 0;
 305 }
 306
 307 /**
 308  * gfs2_log_release - Release a given number of log blocks
 309  * @sdp: The GFS2 superblock
 310  * @blks: The number of blocks
 311  *
 312  */
 313
 314 void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks)
 315 {
 316
 317         gfs2_log_lock(sdp);
 318         sdp->sd_log_blks_free += blks;
 319         gfs2_assert_withdraw(sdp,
 320                              sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks);
 321         gfs2_log_unlock(sdp);
 322         up_read(&sdp->sd_log_flush_lock);
 323 }
 324
 325 static u64 log_bmap(struct gfs2_sbd *sdp, unsigned int lbn)
 326 {
 327         struct inode *inode = sdp->sd_jdesc->jd_inode;
 328         int error;
 329         struct buffer_head bh_map = { .b_state = 0, .b_blocknr = 0 };
 330
 331         bh_map.b_size = 1 << inode->i_blkbits;
 332         error = gfs2_block_map(inode, lbn, 0, &bh_map);
 333         if (error || !bh_map.b_blocknr)
 334                 printk(KERN_INFO "error=%d, dbn=%llu lbn=%u", error,
 335                        (unsigned long long)bh_map.b_blocknr, lbn);
 336         gfs2_assert_withdraw(sdp, !error && bh_map.b_blocknr);
 337
 338         return bh_map.b_blocknr;
 339 }
 340
 341 /**
 342  * log_distance - Compute distance between two journal blocks
 343  * @sdp: The GFS2 superblock
 344  * @newer: The most recent journal block of the pair
 345  * @older: The older journal block of the pair
 346  *
 347  *   Compute the distance (in the journal direction) between two
 348  *   blocks in the journal
 349  *
 350  * Returns: the distance in blocks
 351  */
 352
 353 static inline unsigned int log_distance(struct gfs2_sbd *sdp, unsigned int newer,
 354                                         unsigned int older)
 355 {
 356         int dist;
 357
 358         dist = newer - older;
 359         if (dist < 0)
 360                 dist += sdp->sd_jdesc->jd_blocks;
 361
 362         return dist;
 363 }
 364
 365 /**
 366  * calc_reserved - Calculate the number of blocks to reserve when
 367  *                 refunding a transaction's unused buffers.
 368  * @sdp: The GFS2 superblock
 369  *
 370  * This is complex.  We need to reserve room for all our currently used
 371  * metadata buffers (e.g. normal file I/O rewriting file time stamps) and
 372  * all our journaled data buffers for journaled files (e.g. files in the
 373  * meta_fs like rindex, or files for which chattr +j was done.)
 374  * If we don't reserve enough space, gfs2_log_refund and gfs2_log_flush
 375  * will count it as free space (sd_log_blks_free) and corruption will follow.
 376  *
 377  * We can have metadata bufs and jdata bufs in the same journal.  So each
 378  * type gets its own log header, for which we need to reserve a block.
 379  * In fact, each type has the potential for needing more than one header
 380  * in cases where we have more buffers than will fit on a journal page.
 381  * Metadata journal entries take up half the space of journaled buffer entries.
 382  * Thus, metadata entries have buf_limit (502) and journaled buffers have
 383  * databuf_limit (251) before they cause a wrap around.
 384  *
 385  * Also, we need to reserve blocks for revoke journal entries and one for an
 386  * overall header for the lot.
 387  *
 388  * Returns: the number of blocks reserved
 389  */
 390 static unsigned int calc_reserved(struct gfs2_sbd *sdp)
 391 {
 392         unsigned int reserved = 0;
 393         unsigned int mbuf_limit, metabufhdrs_needed;
 394         unsigned int dbuf_limit, databufhdrs_needed;
 395         unsigned int revokes = 0;
 396
 397         mbuf_limit = buf_limit(sdp);
 398         metabufhdrs_needed = (sdp->sd_log_commited_buf +
 399                               (mbuf_limit - 1)) / mbuf_limit;
 400         dbuf_limit = databuf_limit(sdp);
 401         databufhdrs_needed = (sdp->sd_log_commited_databuf +
 402                               (dbuf_limit - 1)) / dbuf_limit;
 403
 404         if (sdp->sd_log_commited_revoke)
 405                 revokes = gfs2_struct2blk(sdp, sdp->sd_log_commited_revoke,
 406                                           sizeof(u64));
 407
 408         reserved = sdp->sd_log_commited_buf + metabufhdrs_needed +
 409                 sdp->sd_log_commited_databuf + databufhdrs_needed +
 410                 revokes;
 411         /* One for the overall header */
 412         if (reserved)
 413                 reserved++;
 414         return reserved;
 415 }
 416
 417 static unsigned int current_tail(struct gfs2_sbd *sdp)
 418 {
 419         struct gfs2_ail *ai;
 420         unsigned int tail;
 421
 422         gfs2_log_lock(sdp);
 423
 424         if (list_empty(&sdp->sd_ail1_list)) {
 425                 tail = sdp->sd_log_head;
 426         } else {
 427                 ai = list_entry(sdp->sd_ail1_list.prev, struct gfs2_ail, ai_list);
 428                 tail = ai->ai_first;
 429         }
 430
 431         gfs2_log_unlock(sdp);
 432
 433         return tail;
 434 }
 435
 436 static inline void log_incr_head(struct gfs2_sbd *sdp)
 437 {
 438         if (sdp->sd_log_flush_head == sdp->sd_log_tail)
 439                 gfs2_assert_withdraw(sdp, sdp->sd_log_flush_head == sdp->sd_log_head);
 440
 441         if (++sdp->sd_log_flush_head == sdp->sd_jdesc->jd_blocks) {
 442                 sdp->sd_log_flush_head = 0;
 443                 sdp->sd_log_flush_wrapped = 1;
 444         }
 445 }
 446
 447 /**
 448  * gfs2_log_get_buf - Get and initialize a buffer to use for log control data
 449  * @sdp: The GFS2 superblock
 450  *
 451  * Returns: the buffer_head
 452  */
 453
 454 struct buffer_head *gfs2_log_get_buf(struct gfs2_sbd *sdp)
 455 {
 456         u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head);
 457         struct gfs2_log_buf *lb;
 458         struct buffer_head *bh;
 459
 460         lb = kzalloc(sizeof(struct gfs2_log_buf), GFP_NOFS | __GFP_NOFAIL);
 461         list_add(&lb->lb_list, &sdp->sd_log_flush_list);
 462
 463         bh = lb->lb_bh = sb_getblk(sdp->sd_vfs, blkno);
 464         lock_buffer(bh);
 465         memset(bh->b_data, 0, bh->b_size);
 466         set_buffer_uptodate(bh);
 467         clear_buffer_dirty(bh);
 468         unlock_buffer(bh);
 469
 470         log_incr_head(sdp);
 471
 472         return bh;
 473 }
 474
 475 /**
 476  * gfs2_log_fake_buf - Build a fake buffer head to write metadata buffer to log
 477  * @sdp: the filesystem
 478  * @data: the data the buffer_head should point to
 479  *
 480  * Returns: the log buffer descriptor
 481  */
 482
 483 struct buffer_head *gfs2_log_fake_buf(struct gfs2_sbd *sdp,
 484                                       struct buffer_head *real)
 485 {
 486         u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head);
 487         struct gfs2_log_buf *lb;
 488         struct buffer_head *bh;
 489
 490         lb = kzalloc(sizeof(struct gfs2_log_buf), GFP_NOFS | __GFP_NOFAIL);
 491         list_add(&lb->lb_list, &sdp->sd_log_flush_list);
 492         lb->lb_real = real;
 493
 494         bh = lb->lb_bh = alloc_buffer_head(GFP_NOFS | __GFP_NOFAIL);
 495         atomic_set(&bh->b_count, 1);
 496         bh->b_state = (1 << BH_Mapped) | (1 << BH_Uptodate);
 497         set_bh_page(bh, real->b_page, bh_offset(real));
 498         bh->b_blocknr = blkno;
 499         bh->b_size = sdp->sd_sb.sb_bsize;
 500         bh->b_bdev = sdp->sd_vfs->s_bdev;
 501
 502         log_incr_head(sdp);
 503
 504         return bh;
 505 }
 506
 507 static void log_pull_tail(struct gfs2_sbd *sdp, unsigned int new_tail)
 508 {
 509         unsigned int dist = log_distance(sdp, new_tail, sdp->sd_log_tail);
 510
 511         ail2_empty(sdp, new_tail);
 512
 513         gfs2_log_lock(sdp);
 514         sdp->sd_log_blks_free += dist;
 515         gfs2_assert_withdraw(sdp, sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks);
 516         gfs2_log_unlock(sdp);
 517
 518         sdp->sd_log_tail = new_tail;
 519 }
 520
 521 /**
 522  * log_write_header - Get and initialize a journal header buffer
 523  * @sdp: The GFS2 superblock
 524  *
 525  * Returns: the initialized log buffer descriptor
 526  */
 527
 528 static void log_write_header(struct gfs2_sbd *sdp, u32 flags, int pull)
 529 {
 530         u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head);
 531         struct buffer_head *bh;
 532         struct gfs2_log_header *lh;
 533         unsigned int tail;
 534         u32 hash;
 535
 536         bh = sb_getblk(sdp->sd_vfs, blkno);
 537         lock_buffer(bh);
 538         memset(bh->b_data, 0, bh->b_size);
 539         set_buffer_uptodate(bh);
 540         clear_buffer_dirty(bh);
 541         unlock_buffer(bh);
 542
 543         gfs2_ail1_empty(sdp, 0);
 544         tail = current_tail(sdp);
 545
 546         lh = (struct gfs2_log_header *)bh->b_data;
 547         memset(lh, 0, sizeof(struct gfs2_log_header));
 548         lh->lh_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
 549         lh->lh_header.mh_type = cpu_to_be32(GFS2_METATYPE_LH);
 550         lh->lh_header.mh_format = cpu_to_be32(GFS2_FORMAT_LH);
 551         lh->lh_sequence = cpu_to_be64(sdp->sd_log_sequence++);
 552         lh->lh_flags = cpu_to_be32(flags);
 553         lh->lh_tail = cpu_to_be32(tail);
 554         lh->lh_blkno = cpu_to_be32(sdp->sd_log_flush_head);
 555         hash = gfs2_disk_hash(bh->b_data, sizeof(struct gfs2_log_header));
 556         lh->lh_hash = cpu_to_be32(hash);
 557
 558         set_buffer_dirty(bh);
 559         if (sync_dirty_buffer(bh))
 560                 gfs2_io_error_bh(sdp, bh);
 561         brelse(bh);
 562
 563         if (sdp->sd_log_tail != tail)
 564                 log_pull_tail(sdp, tail);
 565         else
 566                 gfs2_assert_withdraw(sdp, !pull);
 567
 568         sdp->sd_log_idle = (tail == sdp->sd_log_flush_head);
 569         log_incr_head(sdp);
 570 }
 571
 572 static void log_flush_commit(struct gfs2_sbd *sdp)
 573 {
 574         struct list_head *head = &sdp->sd_log_flush_list;
 575         struct gfs2_log_buf *lb;
 576         struct buffer_head *bh;
 577         int flushcount = 0;
 578
 579         while (!list_empty(head)) {
 580                 lb = list_entry(head->next, struct gfs2_log_buf, lb_list);
 581                 list_del(&lb->lb_list);
 582                 bh = lb->lb_bh;
 583
 584                 wait_on_buffer(bh);
 585                 if (!buffer_uptodate(bh))
 586                         gfs2_io_error_bh(sdp, bh);
 587                 if (lb->lb_real) {
 588                         while (atomic_read(&bh->b_count) != 1)  /* Grrrr... */
 589                                 schedule();
 590                         free_buffer_head(bh);
 591                 } else
 592                         brelse(bh);
 593                 kfree(lb);
 594                 flushcount++;
 595         }
 596
 597         /* If nothing was journaled, the header is unplanned and unwanted. */
 598         if (flushcount) {
 599                 log_write_header(sdp, 0, 0);
 600         } else {
 601                 unsigned int tail;
 602                 tail = current_tail(sdp);
 603
 604                 gfs2_ail1_empty(sdp, 0);
 605                 if (sdp->sd_log_tail != tail)
 606                         log_pull_tail(sdp, tail);
 607         }
 608 }
 609
 610 /**
 611  * gfs2_log_flush - flush incore transaction(s)
 612  * @sdp: the filesystem
 613  * @gl: The glock structure to flush.  If NULL, flush the whole incore log
 614  *
 615  */
 616
 617 void gfs2_log_flush(struct gfs2_sbd *sdp, struct gfs2_glock *gl)
 618 {
 619         struct gfs2_ail *ai;
 620
 621         down_write(&sdp->sd_log_flush_lock);
 622
 623         if (gl) {
 624                 gfs2_log_lock(sdp);
 625                 if (list_empty(&gl->gl_le.le_list)) {
 626                         gfs2_log_unlock(sdp);
 627                         up_write(&sdp->sd_log_flush_lock);
 628                         return;
 629                 }
 630                 gfs2_log_unlock(sdp);
 631         }
 632
 633         ai = kzalloc(sizeof(struct gfs2_ail), GFP_NOFS | __GFP_NOFAIL);
 634         INIT_LIST_HEAD(&ai->ai_ail1_list);
 635         INIT_LIST_HEAD(&ai->ai_ail2_list);
 636
 637         gfs2_assert_withdraw(sdp,
 638                              sdp->sd_log_num_buf + sdp->sd_log_num_jdata ==
 639                              sdp->sd_log_commited_buf +
 640                              sdp->sd_log_commited_databuf);
 641         gfs2_assert_withdraw(sdp,
 642                         sdp->sd_log_num_revoke == sdp->sd_log_commited_revoke);
 643
 644         sdp->sd_log_flush_head = sdp->sd_log_head;
 645         sdp->sd_log_flush_wrapped = 0;
 646         ai->ai_first = sdp->sd_log_flush_head;
 647
 648         lops_before_commit(sdp);
 649         if (!list_empty(&sdp->sd_log_flush_list))
 650                 log_flush_commit(sdp);
 651         else if (sdp->sd_log_tail != current_tail(sdp) && !sdp->sd_log_idle){
 652                 gfs2_log_lock(sdp);
 653                 sdp->sd_log_blks_free--; /* Adjust for unreserved buffer */
 654                 gfs2_log_unlock(sdp);
 655                 log_write_header(sdp, 0, PULL);
 656         }
 657         lops_after_commit(sdp, ai);
 658
 659         gfs2_log_lock(sdp);
 660         sdp->sd_log_head = sdp->sd_log_flush_head;
 661         sdp->sd_log_blks_reserved = 0;
 662         sdp->sd_log_commited_buf = 0;
 663         sdp->sd_log_commited_databuf = 0;
 664         sdp->sd_log_commited_revoke = 0;
 665
 666         if (!list_empty(&ai->ai_ail1_list)) {
 667                 list_add(&ai->ai_list, &sdp->sd_ail1_list);
 668                 ai = NULL;
 669         }
 670         gfs2_log_unlock(sdp);
 671
 672         sdp->sd_vfs->s_dirt = 0;
 673         up_write(&sdp->sd_log_flush_lock);
 674
 675         kfree(ai);
 676 }
 677
 678 static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
 679 {
 680         unsigned int reserved;
 681         unsigned int old;
 682
 683         gfs2_log_lock(sdp);
 684
 685         sdp->sd_log_commited_buf += tr->tr_num_buf_new - tr->tr_num_buf_rm;
 686         sdp->sd_log_commited_databuf += tr->tr_num_databuf_new -
 687                 tr->tr_num_databuf_rm;
 688         gfs2_assert_withdraw(sdp, (((int)sdp->sd_log_commited_buf) >= 0) ||
 689                              (((int)sdp->sd_log_commited_databuf) >= 0));
 690         sdp->sd_log_commited_revoke += tr->tr_num_revoke - tr->tr_num_revoke_rm;
 691         gfs2_assert_withdraw(sdp, ((int)sdp->sd_log_commited_revoke) >= 0);
 692         reserved = calc_reserved(sdp);
 693         old = sdp->sd_log_blks_free;
 694         sdp->sd_log_blks_free += tr->tr_reserved -
 695                                  (reserved - sdp->sd_log_blks_reserved);
 696
 697         gfs2_assert_withdraw(sdp, sdp->sd_log_blks_free >= old);
 698         gfs2_assert_withdraw(sdp, sdp->sd_log_blks_free <=
 699                              sdp->sd_jdesc->jd_blocks);
 700
 701         sdp->sd_log_blks_reserved = reserved;
 702
 703         gfs2_log_unlock(sdp);
 704 }
 705
 706 /**
 707  * gfs2_log_commit - Commit a transaction to the log
 708  * @sdp: the filesystem
 709  * @tr: the transaction
 710  *
 711  * Returns: errno
 712  */
 713
 714 void gfs2_log_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
 715 {
 716         log_refund(sdp, tr);
 717         lops_incore_commit(sdp, tr);
 718
 719         sdp->sd_vfs->s_dirt = 1;
 720         up_read(&sdp->sd_log_flush_lock);
 721
 722         gfs2_log_lock(sdp);
 723         if (sdp->sd_log_num_buf > gfs2_tune_get(sdp, gt_incore_log_blocks))
 724                 wake_up_process(sdp->sd_logd_process);
 725         gfs2_log_unlock(sdp);
 726 }
 727
 728 /**
 729  * gfs2_log_shutdown - write a shutdown header into a journal
 730  * @sdp: the filesystem
 731  *
 732  */
 733
 734 void gfs2_log_shutdown(struct gfs2_sbd *sdp)
 735 {
 736         down_write(&sdp->sd_log_flush_lock);
 737
 738         gfs2_assert_withdraw(sdp, !sdp->sd_log_blks_reserved);
 739         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_gl);
 740         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_buf);
 741         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_jdata);
 742         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
 743         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_rg);
 744         gfs2_assert_withdraw(sdp, !sdp->sd_log_num_databuf);
 745         gfs2_assert_withdraw(sdp, list_empty(&sdp->sd_ail1_list));
 746
 747         sdp->sd_log_flush_head = sdp->sd_log_head;
 748         sdp->sd_log_flush_wrapped = 0;
 749
 750         log_write_header(sdp, GFS2_LOG_HEAD_UNMOUNT,
 751                          (sdp->sd_log_tail == current_tail(sdp)) ? 0 : PULL);
 752
 753         gfs2_assert_warn(sdp, sdp->sd_log_blks_free == sdp->sd_jdesc->jd_blocks);
 754         gfs2_assert_warn(sdp, sdp->sd_log_head == sdp->sd_log_tail);
 755         gfs2_assert_warn(sdp, list_empty(&sdp->sd_ail2_list));
 756
 757         sdp->sd_log_head = sdp->sd_log_flush_head;
 758         sdp->sd_log_tail = sdp->sd_log_head;
 759
 760         up_write(&sdp->sd_log_flush_lock);
 761 }
 762
 763
 764 /**
 765  * gfs2_meta_syncfs - sync all the buffers in a filesystem
 766  * @sdp: the filesystem
 767  *
 768  */
 769
 770 void gfs2_meta_syncfs(struct gfs2_sbd *sdp)
 771 {
 772         gfs2_log_flush(sdp, NULL);
 773         for (;;) {
 774                 gfs2_ail1_start(sdp, DIO_ALL);
 775                 if (gfs2_ail1_empty(sdp, DIO_ALL))
 776                         break;
 777                 msleep(10);
 778         }
 779 }
 780