linux/fs/ocfs2/journal.h
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   1/* -*- mode: c; c-basic-offset: 8; -*-
   2 * vim: noexpandtab sw=8 ts=8 sts=0:
   3 *
   4 * journal.h
   5 *
   6 * Defines journalling api and structures.
   7 *
   8 * Copyright (C) 2003, 2005 Oracle.  All rights reserved.
   9 *
  10 * This program is free software; you can redistribute it and/or
  11 * modify it under the terms of the GNU General Public
  12 * License as published by the Free Software Foundation; either
  13 * version 2 of the License, or (at your option) any later version.
  14 *
  15 * This program is distributed in the hope that it will be useful,
  16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18 * General Public License for more details.
  19 *
  20 * You should have received a copy of the GNU General Public
  21 * License along with this program; if not, write to the
  22 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  23 * Boston, MA 021110-1307, USA.
  24 */
  25
  26#ifndef OCFS2_JOURNAL_H
  27#define OCFS2_JOURNAL_H
  28
  29#include <linux/fs.h>
  30#include <linux/jbd2.h>
  31
  32enum ocfs2_journal_state {
  33        OCFS2_JOURNAL_FREE = 0,
  34        OCFS2_JOURNAL_LOADED,
  35        OCFS2_JOURNAL_IN_SHUTDOWN,
  36};
  37
  38struct ocfs2_super;
  39struct ocfs2_dinode;
  40
  41/*
  42 * The recovery_list is a simple linked list of node numbers to recover.
  43 * It is protected by the recovery_lock.
  44 */
  45
  46struct ocfs2_recovery_map {
  47        unsigned int rm_used;
  48        unsigned int *rm_entries;
  49};
  50
  51
  52struct ocfs2_journal {
  53        enum ocfs2_journal_state   j_state;    /* Journals current state   */
  54
  55        journal_t                 *j_journal; /* The kernels journal type */
  56        struct inode              *j_inode;   /* Kernel inode pointing to
  57                                               * this journal             */
  58        struct ocfs2_super        *j_osb;     /* pointer to the super
  59                                               * block for the node
  60                                               * we're currently
  61                                               * running on -- not
  62                                               * necessarily the super
  63                                               * block from the node
  64                                               * which we usually run
  65                                               * from (recovery,
  66                                               * etc)                     */
  67        struct buffer_head        *j_bh;      /* Journal disk inode block */
  68        atomic_t                  j_num_trans; /* Number of transactions
  69                                                * currently in the system. */
  70        unsigned long             j_trans_id;
  71        struct rw_semaphore       j_trans_barrier;
  72        wait_queue_head_t         j_checkpointed;
  73
  74        spinlock_t                j_lock;
  75        struct list_head          j_la_cleanups;
  76        struct work_struct        j_recovery_work;
  77};
  78
  79extern spinlock_t trans_inc_lock;
  80
  81/* wrap j_trans_id so we never have it equal to zero. */
  82static inline unsigned long ocfs2_inc_trans_id(struct ocfs2_journal *j)
  83{
  84        unsigned long old_id;
  85        spin_lock(&trans_inc_lock);
  86        old_id = j->j_trans_id++;
  87        if (unlikely(!j->j_trans_id))
  88                j->j_trans_id = 1;
  89        spin_unlock(&trans_inc_lock);
  90        return old_id;
  91}
  92
  93static inline void ocfs2_set_ci_lock_trans(struct ocfs2_journal *journal,
  94                                           struct ocfs2_caching_info *ci)
  95{
  96        spin_lock(&trans_inc_lock);
  97        ci->ci_last_trans = journal->j_trans_id;
  98        spin_unlock(&trans_inc_lock);
  99}
 100
 101/* Used to figure out whether it's safe to drop a metadata lock on an
 102 * cached object. Returns true if all the object's changes have been
 103 * checkpointed to disk. You should be holding the spinlock on the
 104 * metadata lock while calling this to be sure that nobody can take
 105 * the lock and put it on another transaction. */
 106static inline int ocfs2_ci_fully_checkpointed(struct ocfs2_caching_info *ci)
 107{
 108        int ret;
 109        struct ocfs2_journal *journal =
 110                OCFS2_SB(ocfs2_metadata_cache_get_super(ci))->journal;
 111
 112        spin_lock(&trans_inc_lock);
 113        ret = time_after(journal->j_trans_id, ci->ci_last_trans);
 114        spin_unlock(&trans_inc_lock);
 115        return ret;
 116}
 117
 118/* convenience function to check if an object backed by struct
 119 * ocfs2_caching_info  is still new (has never hit disk) Will do you a
 120 * favor and set created_trans = 0 when you've
 121 * been checkpointed.  returns '1' if the ci is still new. */
 122static inline int ocfs2_ci_is_new(struct ocfs2_caching_info *ci)
 123{
 124        int ret;
 125        struct ocfs2_journal *journal =
 126                OCFS2_SB(ocfs2_metadata_cache_get_super(ci))->journal;
 127
 128        spin_lock(&trans_inc_lock);
 129        ret = !(time_after(journal->j_trans_id, ci->ci_created_trans));
 130        if (!ret)
 131                ci->ci_created_trans = 0;
 132        spin_unlock(&trans_inc_lock);
 133        return ret;
 134}
 135
 136/* Wrapper for inodes so we can check system files */
 137static inline int ocfs2_inode_is_new(struct inode *inode)
 138{
 139        /* System files are never "new" as they're written out by
 140         * mkfs. This helps us early during mount, before we have the
 141         * journal open and j_trans_id could be junk. */
 142        if (OCFS2_I(inode)->ip_flags & OCFS2_INODE_SYSTEM_FILE)
 143                return 0;
 144
 145        return ocfs2_ci_is_new(INODE_CACHE(inode));
 146}
 147
 148static inline void ocfs2_ci_set_new(struct ocfs2_super *osb,
 149                                    struct ocfs2_caching_info *ci)
 150{
 151        spin_lock(&trans_inc_lock);
 152        ci->ci_created_trans = osb->journal->j_trans_id;
 153        spin_unlock(&trans_inc_lock);
 154}
 155
 156/* Exported only for the journal struct init code in super.c. Do not call. */
 157void ocfs2_orphan_scan_init(struct ocfs2_super *osb);
 158void ocfs2_orphan_scan_start(struct ocfs2_super *osb);
 159void ocfs2_orphan_scan_stop(struct ocfs2_super *osb);
 160void ocfs2_orphan_scan_exit(struct ocfs2_super *osb);
 161
 162void ocfs2_complete_recovery(struct work_struct *work);
 163void ocfs2_wait_for_recovery(struct ocfs2_super *osb);
 164
 165int ocfs2_recovery_init(struct ocfs2_super *osb);
 166void ocfs2_recovery_exit(struct ocfs2_super *osb);
 167
 168int ocfs2_compute_replay_slots(struct ocfs2_super *osb);
 169/*
 170 *  Journal Control:
 171 *  Initialize, Load, Shutdown, Wipe a journal.
 172 *
 173 *  ocfs2_journal_init     - Initialize journal structures in the OSB.
 174 *  ocfs2_journal_load     - Load the given journal off disk. Replay it if
 175 *                          there's transactions still in there.
 176 *  ocfs2_journal_shutdown - Shutdown a journal, this will flush all
 177 *                          uncommitted, uncheckpointed transactions.
 178 *  ocfs2_journal_wipe     - Wipe transactions from a journal. Optionally
 179 *                          zero out each block.
 180 *  ocfs2_recovery_thread  - Perform recovery on a node. osb is our own osb.
 181 *  ocfs2_mark_dead_nodes - Start recovery on nodes we won't get a heartbeat
 182 *                          event on.
 183 *  ocfs2_start_checkpoint - Kick the commit thread to do a checkpoint.
 184 */
 185void   ocfs2_set_journal_params(struct ocfs2_super *osb);
 186int    ocfs2_journal_init(struct ocfs2_journal *journal,
 187                          int *dirty);
 188void   ocfs2_journal_shutdown(struct ocfs2_super *osb);
 189int    ocfs2_journal_wipe(struct ocfs2_journal *journal,
 190                          int full);
 191int    ocfs2_journal_load(struct ocfs2_journal *journal, int local,
 192                          int replayed);
 193int    ocfs2_check_journals_nolocks(struct ocfs2_super *osb);
 194void   ocfs2_recovery_thread(struct ocfs2_super *osb,
 195                             int node_num);
 196int    ocfs2_mark_dead_nodes(struct ocfs2_super *osb);
 197void   ocfs2_complete_mount_recovery(struct ocfs2_super *osb);
 198void ocfs2_complete_quota_recovery(struct ocfs2_super *osb);
 199
 200static inline void ocfs2_start_checkpoint(struct ocfs2_super *osb)
 201{
 202        atomic_set(&osb->needs_checkpoint, 1);
 203        wake_up(&osb->checkpoint_event);
 204}
 205
 206static inline void ocfs2_checkpoint_inode(struct inode *inode)
 207{
 208        struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 209
 210        if (ocfs2_mount_local(osb))
 211                return;
 212
 213        if (!ocfs2_ci_fully_checkpointed(INODE_CACHE(inode))) {
 214                /* WARNING: This only kicks off a single
 215                 * checkpoint. If someone races you and adds more
 216                 * metadata to the journal, you won't know, and will
 217                 * wind up waiting *alot* longer than necessary. Right
 218                 * now we only use this in clear_inode so that's
 219                 * OK. */
 220                ocfs2_start_checkpoint(osb);
 221
 222                wait_event(osb->journal->j_checkpointed,
 223                           ocfs2_ci_fully_checkpointed(INODE_CACHE(inode)));
 224        }
 225}
 226
 227/*
 228 *  Transaction Handling:
 229 *  Manage the lifetime of a transaction handle.
 230 *
 231 *  ocfs2_start_trans      - Begin a transaction. Give it an upper estimate of
 232 *                          the number of blocks that will be changed during
 233 *                          this handle.
 234 *  ocfs2_commit_trans - Complete a handle. It might return -EIO if
 235 *                       the journal was aborted. The majority of paths don't
 236 *                       check the return value as an error there comes too
 237 *                       late to do anything (and will be picked up in a
 238 *                       later transaction).
 239 *  ocfs2_extend_trans     - Extend a handle by nblocks credits. This may
 240 *                          commit the handle to disk in the process, but will
 241 *                          not release any locks taken during the transaction.
 242 *  ocfs2_journal_access* - Notify the handle that we want to journal this
 243 *                          buffer. Will have to call ocfs2_journal_dirty once
 244 *                          we've actually dirtied it. Type is one of . or .
 245 *                          Always call the specific flavor of
 246 *                          ocfs2_journal_access_*() unless you intend to
 247 *                          manage the checksum by hand.
 248 *  ocfs2_journal_dirty    - Mark a journalled buffer as having dirty data.
 249 *  ocfs2_jbd2_file_inode  - Mark an inode so that its data goes out before
 250 *                           the current handle commits.
 251 */
 252
 253/* You must always start_trans with a number of buffs > 0, but it's
 254 * perfectly legal to go through an entire transaction without having
 255 * dirtied any buffers. */
 256handle_t                    *ocfs2_start_trans(struct ocfs2_super *osb,
 257                                               int max_buffs);
 258int                          ocfs2_commit_trans(struct ocfs2_super *osb,
 259                                                handle_t *handle);
 260int                          ocfs2_extend_trans(handle_t *handle, int nblocks);
 261
 262/*
 263 * Create access is for when we get a newly created buffer and we're
 264 * not gonna read it off disk, but rather fill it ourselves.  Right
 265 * now, we don't do anything special with this (it turns into a write
 266 * request), but this is a good placeholder in case we do...
 267 *
 268 * Write access is for when we read a block off disk and are going to
 269 * modify it. This way the journalling layer knows it may need to make
 270 * a copy of that block (if it's part of another, uncommitted
 271 * transaction) before we do so.
 272 */
 273#define OCFS2_JOURNAL_ACCESS_CREATE 0
 274#define OCFS2_JOURNAL_ACCESS_WRITE  1
 275#define OCFS2_JOURNAL_ACCESS_UNDO   2
 276
 277
 278/* ocfs2_inode */
 279int ocfs2_journal_access_di(handle_t *handle, struct ocfs2_caching_info *ci,
 280                            struct buffer_head *bh, int type);
 281/* ocfs2_extent_block */
 282int ocfs2_journal_access_eb(handle_t *handle, struct ocfs2_caching_info *ci,
 283                            struct buffer_head *bh, int type);
 284/* ocfs2_refcount_block */
 285int ocfs2_journal_access_rb(handle_t *handle, struct ocfs2_caching_info *ci,
 286                            struct buffer_head *bh, int type);
 287/* ocfs2_group_desc */
 288int ocfs2_journal_access_gd(handle_t *handle, struct ocfs2_caching_info *ci,
 289                            struct buffer_head *bh, int type);
 290/* ocfs2_xattr_block */
 291int ocfs2_journal_access_xb(handle_t *handle, struct ocfs2_caching_info *ci,
 292                            struct buffer_head *bh, int type);
 293/* quota blocks */
 294int ocfs2_journal_access_dq(handle_t *handle, struct ocfs2_caching_info *ci,
 295                            struct buffer_head *bh, int type);
 296/* dirblock */
 297int ocfs2_journal_access_db(handle_t *handle, struct ocfs2_caching_info *ci,
 298                            struct buffer_head *bh, int type);
 299/* ocfs2_dx_root_block */
 300int ocfs2_journal_access_dr(handle_t *handle, struct ocfs2_caching_info *ci,
 301                            struct buffer_head *bh, int type);
 302/* ocfs2_dx_leaf */
 303int ocfs2_journal_access_dl(handle_t *handle, struct ocfs2_caching_info *ci,
 304                            struct buffer_head *bh, int type);
 305/* Anything that has no ecc */
 306int ocfs2_journal_access(handle_t *handle, struct ocfs2_caching_info *ci,
 307                         struct buffer_head *bh, int type);
 308
 309/*
 310 * A word about the journal_access/journal_dirty "dance". It is
 311 * entirely legal to journal_access a buffer more than once (as long
 312 * as the access type is the same -- I'm not sure what will happen if
 313 * access type is different but this should never happen anyway) It is
 314 * also legal to journal_dirty a buffer more than once. In fact, you
 315 * can even journal_access a buffer after you've done a
 316 * journal_access/journal_dirty pair. The only thing you cannot do
 317 * however, is journal_dirty a buffer which you haven't yet passed to
 318 * journal_access at least once.
 319 *
 320 * That said, 99% of the time this doesn't matter and this is what the
 321 * path looks like:
 322 *
 323 *      <read a bh>
 324 *      ocfs2_journal_access(handle, bh,        OCFS2_JOURNAL_ACCESS_WRITE);
 325 *      <modify the bh>
 326 *      ocfs2_journal_dirty(handle, bh);
 327 */
 328int                  ocfs2_journal_dirty(handle_t *handle,
 329                                         struct buffer_head *bh);
 330
 331/*
 332 *  Credit Macros:
 333 *  Convenience macros to calculate number of credits needed.
 334 *
 335 *  For convenience sake, I have a set of macros here which calculate
 336 *  the *maximum* number of sectors which will be changed for various
 337 *  metadata updates.
 338 */
 339
 340/* simple file updates like chmod, etc. */
 341#define OCFS2_INODE_UPDATE_CREDITS 1
 342
 343/* extended attribute block update */
 344#define OCFS2_XATTR_BLOCK_UPDATE_CREDITS 1
 345
 346/* Update of a single quota block */
 347#define OCFS2_QUOTA_BLOCK_UPDATE_CREDITS 1
 348
 349/* global quotafile inode update, data block */
 350#define OCFS2_QINFO_WRITE_CREDITS (OCFS2_INODE_UPDATE_CREDITS + \
 351                                   OCFS2_QUOTA_BLOCK_UPDATE_CREDITS)
 352
 353#define OCFS2_LOCAL_QINFO_WRITE_CREDITS OCFS2_QUOTA_BLOCK_UPDATE_CREDITS
 354/*
 355 * The two writes below can accidentally see global info dirty due
 356 * to set_info() quotactl so make them prepared for the writes.
 357 */
 358/* quota data block, global info */
 359/* Write to local quota file */
 360#define OCFS2_QWRITE_CREDITS (OCFS2_QINFO_WRITE_CREDITS + \
 361                              OCFS2_QUOTA_BLOCK_UPDATE_CREDITS)
 362
 363/* global quota data block, local quota data block, global quota inode,
 364 * global quota info */
 365#define OCFS2_QSYNC_CREDITS (OCFS2_QINFO_WRITE_CREDITS + \
 366                             2 * OCFS2_QUOTA_BLOCK_UPDATE_CREDITS)
 367
 368static inline int ocfs2_quota_trans_credits(struct super_block *sb)
 369{
 370        int credits = 0;
 371
 372        if (OCFS2_HAS_RO_COMPAT_FEATURE(sb, OCFS2_FEATURE_RO_COMPAT_USRQUOTA))
 373                credits += OCFS2_QWRITE_CREDITS;
 374        if (OCFS2_HAS_RO_COMPAT_FEATURE(sb, OCFS2_FEATURE_RO_COMPAT_GRPQUOTA))
 375                credits += OCFS2_QWRITE_CREDITS;
 376        return credits;
 377}
 378
 379/* group extend. inode update and last group update. */
 380#define OCFS2_GROUP_EXTEND_CREDITS      (OCFS2_INODE_UPDATE_CREDITS + 1)
 381
 382/* group add. inode update and the new group update. */
 383#define OCFS2_GROUP_ADD_CREDITS (OCFS2_INODE_UPDATE_CREDITS + 1)
 384
 385/* get one bit out of a suballocator: dinode + group descriptor +
 386 * prev. group desc. if we relink. */
 387#define OCFS2_SUBALLOC_ALLOC (3)
 388
 389static inline int ocfs2_inline_to_extents_credits(struct super_block *sb)
 390{
 391        return OCFS2_SUBALLOC_ALLOC + OCFS2_INODE_UPDATE_CREDITS +
 392               ocfs2_quota_trans_credits(sb);
 393}
 394
 395/* dinode + group descriptor update. We don't relink on free yet. */
 396#define OCFS2_SUBALLOC_FREE  (2)
 397
 398#define OCFS2_TRUNCATE_LOG_UPDATE OCFS2_INODE_UPDATE_CREDITS
 399#define OCFS2_TRUNCATE_LOG_FLUSH_ONE_REC (OCFS2_SUBALLOC_FREE                 \
 400                                         + OCFS2_TRUNCATE_LOG_UPDATE)
 401
 402static inline int ocfs2_remove_extent_credits(struct super_block *sb)
 403{
 404        return OCFS2_TRUNCATE_LOG_UPDATE + OCFS2_INODE_UPDATE_CREDITS +
 405               ocfs2_quota_trans_credits(sb);
 406}
 407
 408/* data block for new dir/symlink, 2 for bitmap updates (bitmap fe +
 409 * bitmap block for the new bit) dx_root update for free list */
 410#define OCFS2_DIR_LINK_ADDITIONAL_CREDITS (1 + 2 + 1)
 411
 412static inline int ocfs2_add_dir_index_credits(struct super_block *sb)
 413{
 414        /* 1 block for index, 2 allocs (data, metadata), 1 clusters
 415         * worth of blocks for initial extent. */
 416        return 1 + 2 * OCFS2_SUBALLOC_ALLOC +
 417                ocfs2_clusters_to_blocks(sb, 1);
 418}
 419
 420/* parent fe, parent block, new file entry, index leaf, inode alloc fe, inode
 421 * alloc group descriptor + mkdir/symlink blocks + dir blocks + xattr
 422 * blocks + quota update */
 423static inline int ocfs2_mknod_credits(struct super_block *sb, int is_dir,
 424                                      int xattr_credits)
 425{
 426        int dir_credits = OCFS2_DIR_LINK_ADDITIONAL_CREDITS;
 427
 428        if (is_dir)
 429                dir_credits += ocfs2_add_dir_index_credits(sb);
 430
 431        return 4 + OCFS2_SUBALLOC_ALLOC + dir_credits + xattr_credits +
 432               ocfs2_quota_trans_credits(sb);
 433}
 434
 435/* local alloc metadata change + main bitmap updates */
 436#define OCFS2_WINDOW_MOVE_CREDITS (OCFS2_INODE_UPDATE_CREDITS                 \
 437                                  + OCFS2_SUBALLOC_ALLOC + OCFS2_SUBALLOC_FREE)
 438
 439/* used when we don't need an allocation change for a dir extend. One
 440 * for the dinode, one for the new block. */
 441#define OCFS2_SIMPLE_DIR_EXTEND_CREDITS (2)
 442
 443/* file update (nlink, etc) + directory mtime/ctime + dir entry block + quota
 444 * update on dir + index leaf + dx root update for free list */
 445static inline int ocfs2_link_credits(struct super_block *sb)
 446{
 447        return 2*OCFS2_INODE_UPDATE_CREDITS + 3 +
 448               ocfs2_quota_trans_credits(sb);
 449}
 450
 451/* inode + dir inode (if we unlink a dir), + dir entry block + orphan
 452 * dir inode link + dir inode index leaf + dir index root */
 453static inline int ocfs2_unlink_credits(struct super_block *sb)
 454{
 455        /* The quota update from ocfs2_link_credits is unused here... */
 456        return 2 * OCFS2_INODE_UPDATE_CREDITS + 3 + ocfs2_link_credits(sb);
 457}
 458
 459/* dinode + orphan dir dinode + inode alloc dinode + orphan dir entry +
 460 * inode alloc group descriptor + orphan dir index root +
 461 * orphan dir index leaf */
 462#define OCFS2_DELETE_INODE_CREDITS (3 * OCFS2_INODE_UPDATE_CREDITS + 4)
 463
 464/* dinode update, old dir dinode update, new dir dinode update, old
 465 * dir dir entry, new dir dir entry, dir entry update for renaming
 466 * directory + target unlink + 3 x dir index leaves */
 467static inline int ocfs2_rename_credits(struct super_block *sb)
 468{
 469        return 3 * OCFS2_INODE_UPDATE_CREDITS + 6 + ocfs2_unlink_credits(sb);
 470}
 471
 472/* global bitmap dinode, group desc., relinked group,
 473 * suballocator dinode, group desc., relinked group,
 474 * dinode, xattr block */
 475#define OCFS2_XATTR_BLOCK_CREATE_CREDITS (OCFS2_SUBALLOC_ALLOC * 2 + \
 476                                          + OCFS2_INODE_UPDATE_CREDITS \
 477                                          + OCFS2_XATTR_BLOCK_UPDATE_CREDITS)
 478
 479/* inode update, removal of dx root block from allocator */
 480#define OCFS2_DX_ROOT_REMOVE_CREDITS (OCFS2_INODE_UPDATE_CREDITS +      \
 481                                      OCFS2_SUBALLOC_FREE)
 482
 483static inline int ocfs2_calc_dxi_expand_credits(struct super_block *sb)
 484{
 485        int credits = 1 + OCFS2_SUBALLOC_ALLOC;
 486
 487        credits += ocfs2_clusters_to_blocks(sb, 1);
 488        credits += ocfs2_quota_trans_credits(sb);
 489
 490        return credits;
 491}
 492
 493/* inode update, new refcount block and its allocation credits. */
 494#define OCFS2_REFCOUNT_TREE_CREATE_CREDITS (OCFS2_INODE_UPDATE_CREDITS + 1 \
 495                                            + OCFS2_SUBALLOC_ALLOC)
 496
 497/* inode and the refcount block update. */
 498#define OCFS2_REFCOUNT_TREE_SET_CREDITS (OCFS2_INODE_UPDATE_CREDITS + 1)
 499
 500/*
 501 * inode and the refcount block update.
 502 * It doesn't include the credits for sub alloc change.
 503 * So if we need to free the bit, OCFS2_SUBALLOC_FREE needs to be added.
 504 */
 505#define OCFS2_REFCOUNT_TREE_REMOVE_CREDITS (OCFS2_INODE_UPDATE_CREDITS + 1)
 506
 507/* 2 metadata alloc, 2 new blocks and root refcount block */
 508#define OCFS2_EXPAND_REFCOUNT_TREE_CREDITS (OCFS2_SUBALLOC_ALLOC * 2 + 3)
 509
 510/*
 511 * Please note that the caller must make sure that root_el is the root
 512 * of extent tree. So for an inode, it should be &fe->id2.i_list. Otherwise
 513 * the result may be wrong.
 514 */
 515static inline int ocfs2_calc_extend_credits(struct super_block *sb,
 516                                            struct ocfs2_extent_list *root_el,
 517                                            u32 bits_wanted)
 518{
 519        int bitmap_blocks, sysfile_bitmap_blocks, extent_blocks;
 520
 521        /* bitmap dinode, group desc. + relinked group. */
 522        bitmap_blocks = OCFS2_SUBALLOC_ALLOC;
 523
 524        /* we might need to shift tree depth so lets assume an
 525         * absolute worst case of complete fragmentation.  Even with
 526         * that, we only need one update for the dinode, and then
 527         * however many metadata chunks needed * a remaining suballoc
 528         * alloc. */
 529        sysfile_bitmap_blocks = 1 +
 530                (OCFS2_SUBALLOC_ALLOC - 1) * ocfs2_extend_meta_needed(root_el);
 531
 532        /* this does not include *new* metadata blocks, which are
 533         * accounted for in sysfile_bitmap_blocks. root_el +
 534         * prev. last_eb_blk + blocks along edge of tree.
 535         * calc_symlink_credits passes because we just need 1
 536         * credit for the dinode there. */
 537        extent_blocks = 1 + 1 + le16_to_cpu(root_el->l_tree_depth);
 538
 539        return bitmap_blocks + sysfile_bitmap_blocks + extent_blocks +
 540               ocfs2_quota_trans_credits(sb);
 541}
 542
 543static inline int ocfs2_calc_symlink_credits(struct super_block *sb)
 544{
 545        int blocks = ocfs2_mknod_credits(sb, 0, 0);
 546
 547        /* links can be longer than one block so we may update many
 548         * within our single allocated extent. */
 549        blocks += ocfs2_clusters_to_blocks(sb, 1);
 550
 551        return blocks + ocfs2_quota_trans_credits(sb);
 552}
 553
 554static inline int ocfs2_calc_group_alloc_credits(struct super_block *sb,
 555                                                 unsigned int cpg)
 556{
 557        int blocks;
 558        int bitmap_blocks = OCFS2_SUBALLOC_ALLOC + 1;
 559        /* parent inode update + new block group header + bitmap inode update
 560           + bitmap blocks affected */
 561        blocks = 1 + 1 + 1 + bitmap_blocks;
 562        return blocks;
 563}
 564
 565static inline int ocfs2_calc_tree_trunc_credits(struct super_block *sb,
 566                                                unsigned int clusters_to_del,
 567                                                struct ocfs2_dinode *fe,
 568                                                struct ocfs2_extent_list *last_el)
 569{
 570        /* for dinode + all headers in this pass + update to next leaf */
 571        u16 next_free = le16_to_cpu(last_el->l_next_free_rec);
 572        u16 tree_depth = le16_to_cpu(fe->id2.i_list.l_tree_depth);
 573        int credits = 1 + tree_depth + 1;
 574        int i;
 575
 576        i = next_free - 1;
 577        BUG_ON(i < 0);
 578
 579        /* We may be deleting metadata blocks, so metadata alloc dinode +
 580           one desc. block for each possible delete. */
 581        if (tree_depth && next_free == 1 &&
 582            ocfs2_rec_clusters(last_el, &last_el->l_recs[i]) == clusters_to_del)
 583                credits += 1 + tree_depth;
 584
 585        /* update to the truncate log. */
 586        credits += OCFS2_TRUNCATE_LOG_UPDATE;
 587
 588        credits += ocfs2_quota_trans_credits(sb);
 589
 590        return credits;
 591}
 592
 593static inline int ocfs2_jbd2_file_inode(handle_t *handle, struct inode *inode)
 594{
 595        return jbd2_journal_file_inode(handle, &OCFS2_I(inode)->ip_jinode);
 596}
 597
 598static inline int ocfs2_begin_ordered_truncate(struct inode *inode,
 599                                               loff_t new_size)
 600{
 601        return jbd2_journal_begin_ordered_truncate(
 602                                OCFS2_SB(inode->i_sb)->journal->j_journal,
 603                                &OCFS2_I(inode)->ip_jinode,
 604                                new_size);
 605}
 606
 607#endif /* OCFS2_JOURNAL_H */
 608