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        spinlock_t                j_lock;
  71        unsigned long             j_trans_id;
  72        struct rw_semaphore       j_trans_barrier;
  73        wait_queue_head_t         j_checkpointed;
  74
  75        /* both fields protected by j_lock*/
  76        struct list_head          j_la_cleanups;
  77        struct work_struct        j_recovery_work;
  78};
  79
  80extern spinlock_t trans_inc_lock;
  81
  82/* wrap j_trans_id so we never have it equal to zero. */
  83static inline unsigned long ocfs2_inc_trans_id(struct ocfs2_journal *j)
  84{
  85        unsigned long old_id;
  86        spin_lock(&trans_inc_lock);
  87        old_id = j->j_trans_id++;
  88        if (unlikely(!j->j_trans_id))
  89                j->j_trans_id = 1;
  90        spin_unlock(&trans_inc_lock);
  91        return old_id;
  92}
  93
  94static inline void ocfs2_set_ci_lock_trans(struct ocfs2_journal *journal,
  95                                           struct ocfs2_caching_info *ci)
  96{
  97        spin_lock(&trans_inc_lock);
  98        ci->ci_last_trans = journal->j_trans_id;
  99        spin_unlock(&trans_inc_lock);
 100}
 101
 102/* Used to figure out whether it's safe to drop a metadata lock on an
 103 * cached object. Returns true if all the object's changes have been
 104 * checkpointed to disk. You should be holding the spinlock on the
 105 * metadata lock while calling this to be sure that nobody can take
 106 * the lock and put it on another transaction. */
 107static inline int ocfs2_ci_fully_checkpointed(struct ocfs2_caching_info *ci)
 108{
 109        int ret;
 110        struct ocfs2_journal *journal =
 111                OCFS2_SB(ocfs2_metadata_cache_get_super(ci))->journal;
 112
 113        spin_lock(&trans_inc_lock);
 114        ret = time_after(journal->j_trans_id, ci->ci_last_trans);
 115        spin_unlock(&trans_inc_lock);
 116        return ret;
 117}
 118
 119/* convenience function to check if an object backed by struct
 120 * ocfs2_caching_info  is still new (has never hit disk) Will do you a
 121 * favor and set created_trans = 0 when you've
 122 * been checkpointed.  returns '1' if the ci is still new. */
 123static inline int ocfs2_ci_is_new(struct ocfs2_caching_info *ci)
 124{
 125        int ret;
 126        struct ocfs2_journal *journal =
 127                OCFS2_SB(ocfs2_metadata_cache_get_super(ci))->journal;
 128
 129        spin_lock(&trans_inc_lock);
 130        ret = !(time_after(journal->j_trans_id, ci->ci_created_trans));
 131        if (!ret)
 132                ci->ci_created_trans = 0;
 133        spin_unlock(&trans_inc_lock);
 134        return ret;
 135}
 136
 137/* Wrapper for inodes so we can check system files */
 138static inline int ocfs2_inode_is_new(struct inode *inode)
 139{
 140        /* System files are never "new" as they're written out by
 141         * mkfs. This helps us early during mount, before we have the
 142         * journal open and j_trans_id could be junk. */
 143        if (OCFS2_I(inode)->ip_flags & OCFS2_INODE_SYSTEM_FILE)
 144                return 0;
 145
 146        return ocfs2_ci_is_new(INODE_CACHE(inode));
 147}
 148
 149static inline void ocfs2_ci_set_new(struct ocfs2_super *osb,
 150                                    struct ocfs2_caching_info *ci)
 151{
 152        spin_lock(&trans_inc_lock);
 153        ci->ci_created_trans = osb->journal->j_trans_id;
 154        spin_unlock(&trans_inc_lock);
 155}
 156
 157/* Exported only for the journal struct init code in super.c. Do not call. */
 158void ocfs2_orphan_scan_init(struct ocfs2_super *osb);
 159void ocfs2_orphan_scan_start(struct ocfs2_super *osb);
 160void ocfs2_orphan_scan_stop(struct ocfs2_super *osb);
 161void ocfs2_orphan_scan_exit(struct ocfs2_super *osb);
 162
 163void ocfs2_complete_recovery(struct work_struct *work);
 164void ocfs2_wait_for_recovery(struct ocfs2_super *osb);
 165
 166int ocfs2_recovery_init(struct ocfs2_super *osb);
 167void ocfs2_recovery_exit(struct ocfs2_super *osb);
 168
 169int ocfs2_compute_replay_slots(struct ocfs2_super *osb);
 170/*
 171 *  Journal Control:
 172 *  Initialize, Load, Shutdown, Wipe a journal.
 173 *
 174 *  ocfs2_journal_init     - Initialize journal structures in the OSB.
 175 *  ocfs2_journal_load     - Load the given journal off disk. Replay it if
 176 *                          there's transactions still in there.
 177 *  ocfs2_journal_shutdown - Shutdown a journal, this will flush all
 178 *                          uncommitted, uncheckpointed transactions.
 179 *  ocfs2_journal_wipe     - Wipe transactions from a journal. Optionally
 180 *                          zero out each block.
 181 *  ocfs2_recovery_thread  - Perform recovery on a node. osb is our own osb.
 182 *  ocfs2_mark_dead_nodes - Start recovery on nodes we won't get a heartbeat
 183 *                          event on.
 184 *  ocfs2_start_checkpoint - Kick the commit thread to do a checkpoint.
 185 */
 186void   ocfs2_set_journal_params(struct ocfs2_super *osb);
 187int    ocfs2_journal_init(struct ocfs2_journal *journal,
 188                          int *dirty);
 189void   ocfs2_journal_shutdown(struct ocfs2_super *osb);
 190int    ocfs2_journal_wipe(struct ocfs2_journal *journal,
 191                          int full);
 192int    ocfs2_journal_load(struct ocfs2_journal *journal, int local,
 193                          int replayed);
 194int    ocfs2_check_journals_nolocks(struct ocfs2_super *osb);
 195void   ocfs2_recovery_thread(struct ocfs2_super *osb,
 196                             int node_num);
 197int    ocfs2_mark_dead_nodes(struct ocfs2_super *osb);
 198void   ocfs2_complete_mount_recovery(struct ocfs2_super *osb);
 199void ocfs2_complete_quota_recovery(struct ocfs2_super *osb);
 200
 201static inline void ocfs2_start_checkpoint(struct ocfs2_super *osb)
 202{
 203        atomic_set(&osb->needs_checkpoint, 1);
 204        wake_up(&osb->checkpoint_event);
 205}
 206
 207static inline void ocfs2_checkpoint_inode(struct inode *inode)
 208{
 209        struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 210
 211        if (ocfs2_mount_local(osb))
 212                return;
 213
 214        if (!ocfs2_ci_fully_checkpointed(INODE_CACHE(inode))) {
 215                /* WARNING: This only kicks off a single
 216                 * checkpoint. If someone races you and adds more
 217                 * metadata to the journal, you won't know, and will
 218                 * wind up waiting *a lot* longer than necessary. Right
 219                 * now we only use this in clear_inode so that's
 220                 * OK. */
 221                ocfs2_start_checkpoint(osb);
 222
 223                wait_event(osb->journal->j_checkpointed,
 224                           ocfs2_ci_fully_checkpointed(INODE_CACHE(inode)));
 225        }
 226}
 227
 228/*
 229 *  Transaction Handling:
 230 *  Manage the lifetime of a transaction handle.
 231 *
 232 *  ocfs2_start_trans      - Begin a transaction. Give it an upper estimate of
 233 *                          the number of blocks that will be changed during
 234 *                          this handle.
 235 *  ocfs2_commit_trans - Complete a handle. It might return -EIO if
 236 *                       the journal was aborted. The majority of paths don't
 237 *                       check the return value as an error there comes too
 238 *                       late to do anything (and will be picked up in a
 239 *                       later transaction).
 240 *  ocfs2_extend_trans     - Extend a handle by nblocks credits. This may
 241 *                          commit the handle to disk in the process, but will
 242 *                          not release any locks taken during the transaction.
 243 *  ocfs2_journal_access* - Notify the handle that we want to journal this
 244 *                          buffer. Will have to call ocfs2_journal_dirty once
 245 *                          we've actually dirtied it. Type is one of . or .
 246 *                          Always call the specific flavor of
 247 *                          ocfs2_journal_access_*() unless you intend to
 248 *                          manage the checksum by hand.
 249 *  ocfs2_journal_dirty    - Mark a journalled buffer as having dirty data.
 250 *  ocfs2_jbd2_file_inode  - Mark an inode so that its data goes out before
 251 *                           the current handle commits.
 252 */
 253
 254/* You must always start_trans with a number of buffs > 0, but it's
 255 * perfectly legal to go through an entire transaction without having
 256 * dirtied any buffers. */
 257handle_t                    *ocfs2_start_trans(struct ocfs2_super *osb,
 258                                               int max_buffs);
 259int                          ocfs2_commit_trans(struct ocfs2_super *osb,
 260                                                handle_t *handle);
 261int                          ocfs2_extend_trans(handle_t *handle, int nblocks);
 262
 263/*
 264 * Create access is for when we get a newly created buffer and we're
 265 * not gonna read it off disk, but rather fill it ourselves.  Right
 266 * now, we don't do anything special with this (it turns into a write
 267 * request), but this is a good placeholder in case we do...
 268 *
 269 * Write access is for when we read a block off disk and are going to
 270 * modify it. This way the journalling layer knows it may need to make
 271 * a copy of that block (if it's part of another, uncommitted
 272 * transaction) before we do so.
 273 */
 274#define OCFS2_JOURNAL_ACCESS_CREATE 0
 275#define OCFS2_JOURNAL_ACCESS_WRITE  1
 276#define OCFS2_JOURNAL_ACCESS_UNDO   2
 277
 278
 279/* ocfs2_inode */
 280int ocfs2_journal_access_di(handle_t *handle, struct ocfs2_caching_info *ci,
 281                            struct buffer_head *bh, int type);
 282/* ocfs2_extent_block */
 283int ocfs2_journal_access_eb(handle_t *handle, struct ocfs2_caching_info *ci,
 284                            struct buffer_head *bh, int type);
 285/* ocfs2_refcount_block */
 286int ocfs2_journal_access_rb(handle_t *handle, struct ocfs2_caching_info *ci,
 287                            struct buffer_head *bh, int type);
 288/* ocfs2_group_desc */
 289int ocfs2_journal_access_gd(handle_t *handle, struct ocfs2_caching_info *ci,
 290                            struct buffer_head *bh, int type);
 291/* ocfs2_xattr_block */
 292int ocfs2_journal_access_xb(handle_t *handle, struct ocfs2_caching_info *ci,
 293                            struct buffer_head *bh, int type);
 294/* quota blocks */
 295int ocfs2_journal_access_dq(handle_t *handle, struct ocfs2_caching_info *ci,
 296                            struct buffer_head *bh, int type);
 297/* dirblock */
 298int ocfs2_journal_access_db(handle_t *handle, struct ocfs2_caching_info *ci,
 299                            struct buffer_head *bh, int type);
 300/* ocfs2_dx_root_block */
 301int ocfs2_journal_access_dr(handle_t *handle, struct ocfs2_caching_info *ci,
 302                            struct buffer_head *bh, int type);
 303/* ocfs2_dx_leaf */
 304int ocfs2_journal_access_dl(handle_t *handle, struct ocfs2_caching_info *ci,
 305                            struct buffer_head *bh, int type);
 306/* Anything that has no ecc */
 307int ocfs2_journal_access(handle_t *handle, struct ocfs2_caching_info *ci,
 308                         struct buffer_head *bh, int type);
 309
 310/*
 311 * A word about the journal_access/journal_dirty "dance". It is
 312 * entirely legal to journal_access a buffer more than once (as long
 313 * as the access type is the same -- I'm not sure what will happen if
 314 * access type is different but this should never happen anyway) It is
 315 * also legal to journal_dirty a buffer more than once. In fact, you
 316 * can even journal_access a buffer after you've done a
 317 * journal_access/journal_dirty pair. The only thing you cannot do
 318 * however, is journal_dirty a buffer which you haven't yet passed to
 319 * journal_access at least once.
 320 *
 321 * That said, 99% of the time this doesn't matter and this is what the
 322 * path looks like:
 323 *
 324 *      <read a bh>
 325 *      ocfs2_journal_access(handle, bh,        OCFS2_JOURNAL_ACCESS_WRITE);
 326 *      <modify the bh>
 327 *      ocfs2_journal_dirty(handle, bh);
 328 */
 329void ocfs2_journal_dirty(handle_t *handle, 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, allocation of directory block, dx_root
 409 * update for free list */
 410#define OCFS2_DIR_LINK_ADDITIONAL_CREDITS (1 + OCFS2_SUBALLOC_ALLOC + 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 +
 445 * previous dirblock update in the free list */
 446static inline int ocfs2_link_credits(struct super_block *sb)
 447{
 448        return 2*OCFS2_INODE_UPDATE_CREDITS + 4 +
 449               ocfs2_quota_trans_credits(sb);
 450}
 451
 452/* inode + dir inode (if we unlink a dir), + dir entry block + orphan
 453 * dir inode link + dir inode index leaf + dir index root */
 454static inline int ocfs2_unlink_credits(struct super_block *sb)
 455{
 456        /* The quota update from ocfs2_link_credits is unused here... */
 457        return 2 * OCFS2_INODE_UPDATE_CREDITS + 3 + ocfs2_link_credits(sb);
 458}
 459
 460/* dinode + orphan dir dinode + inode alloc dinode + orphan dir entry +
 461 * inode alloc group descriptor + orphan dir index root +
 462 * orphan dir index leaf */
 463#define OCFS2_DELETE_INODE_CREDITS (3 * OCFS2_INODE_UPDATE_CREDITS + 4)
 464
 465/* dinode update, old dir dinode update, new dir dinode update, old
 466 * dir dir entry, new dir dir entry, dir entry update for renaming
 467 * directory + target unlink + 3 x dir index leaves */
 468static inline int ocfs2_rename_credits(struct super_block *sb)
 469{
 470        return 3 * OCFS2_INODE_UPDATE_CREDITS + 6 + ocfs2_unlink_credits(sb);
 471}
 472
 473/* global bitmap dinode, group desc., relinked group,
 474 * suballocator dinode, group desc., relinked group,
 475 * dinode, xattr block */
 476#define OCFS2_XATTR_BLOCK_CREATE_CREDITS (OCFS2_SUBALLOC_ALLOC * 2 + \
 477                                          + OCFS2_INODE_UPDATE_CREDITS \
 478                                          + OCFS2_XATTR_BLOCK_UPDATE_CREDITS)
 479
 480/* inode update, removal of dx root block from allocator */
 481#define OCFS2_DX_ROOT_REMOVE_CREDITS (OCFS2_INODE_UPDATE_CREDITS +      \
 482                                      OCFS2_SUBALLOC_FREE)
 483
 484static inline int ocfs2_calc_dxi_expand_credits(struct super_block *sb)
 485{
 486        int credits = 1 + OCFS2_SUBALLOC_ALLOC;
 487
 488        credits += ocfs2_clusters_to_blocks(sb, 1);
 489        credits += ocfs2_quota_trans_credits(sb);
 490
 491        return credits;
 492}
 493
 494/* inode update, new refcount block and its allocation credits. */
 495#define OCFS2_REFCOUNT_TREE_CREATE_CREDITS (OCFS2_INODE_UPDATE_CREDITS + 1 \
 496                                            + OCFS2_SUBALLOC_ALLOC)
 497
 498/* inode and the refcount block update. */
 499#define OCFS2_REFCOUNT_TREE_SET_CREDITS (OCFS2_INODE_UPDATE_CREDITS + 1)
 500
 501/*
 502 * inode and the refcount block update.
 503 * It doesn't include the credits for sub alloc change.
 504 * So if we need to free the bit, OCFS2_SUBALLOC_FREE needs to be added.
 505 */
 506#define OCFS2_REFCOUNT_TREE_REMOVE_CREDITS (OCFS2_INODE_UPDATE_CREDITS + 1)
 507
 508/* 2 metadata alloc, 2 new blocks and root refcount block */
 509#define OCFS2_EXPAND_REFCOUNT_TREE_CREDITS (OCFS2_SUBALLOC_ALLOC * 2 + 3)
 510
 511/*
 512 * Please note that the caller must make sure that root_el is the root
 513 * of extent tree. So for an inode, it should be &fe->id2.i_list. Otherwise
 514 * the result may be wrong.
 515 */
 516static inline int ocfs2_calc_extend_credits(struct super_block *sb,
 517                                            struct ocfs2_extent_list *root_el,
 518                                            u32 bits_wanted)
 519{
 520        int bitmap_blocks, sysfile_bitmap_blocks, extent_blocks;
 521
 522        /* bitmap dinode, group desc. + relinked group. */
 523        bitmap_blocks = OCFS2_SUBALLOC_ALLOC;
 524
 525        /* we might need to shift tree depth so lets assume an
 526         * absolute worst case of complete fragmentation.  Even with
 527         * that, we only need one update for the dinode, and then
 528         * however many metadata chunks needed * a remaining suballoc
 529         * alloc. */
 530        sysfile_bitmap_blocks = 1 +
 531                (OCFS2_SUBALLOC_ALLOC - 1) * ocfs2_extend_meta_needed(root_el);
 532
 533        /* this does not include *new* metadata blocks, which are
 534         * accounted for in sysfile_bitmap_blocks. root_el +
 535         * prev. last_eb_blk + blocks along edge of tree.
 536         * calc_symlink_credits passes because we just need 1
 537         * credit for the dinode there. */
 538        extent_blocks = 1 + 1 + le16_to_cpu(root_el->l_tree_depth);
 539
 540        return bitmap_blocks + sysfile_bitmap_blocks + extent_blocks +
 541               ocfs2_quota_trans_credits(sb);
 542}
 543
 544static inline int ocfs2_calc_symlink_credits(struct super_block *sb)
 545{
 546        int blocks = ocfs2_mknod_credits(sb, 0, 0);
 547
 548        /* links can be longer than one block so we may update many
 549         * within our single allocated extent. */
 550        blocks += ocfs2_clusters_to_blocks(sb, 1);
 551
 552        return blocks + ocfs2_quota_trans_credits(sb);
 553}
 554
 555static inline int ocfs2_calc_group_alloc_credits(struct super_block *sb,
 556                                                 unsigned int cpg)
 557{
 558        int blocks;
 559        int bitmap_blocks = OCFS2_SUBALLOC_ALLOC + 1;
 560        /* parent inode update + new block group header + bitmap inode update
 561           + bitmap blocks affected */
 562        blocks = 1 + 1 + 1 + bitmap_blocks;
 563        return blocks;
 564}
 565
 566/*
 567 * Allocating a discontiguous block group requires the credits from
 568 * ocfs2_calc_group_alloc_credits() as well as enough credits to fill
 569 * the group descriptor's extent list.  The caller already has started
 570 * the transaction with ocfs2_calc_group_alloc_credits().  They extend
 571 * it with these credits.
 572 */
 573static inline int ocfs2_calc_bg_discontig_credits(struct super_block *sb)
 574{
 575        return ocfs2_extent_recs_per_gd(sb);
 576}
 577
 578static inline int ocfs2_calc_tree_trunc_credits(struct super_block *sb,
 579                                                unsigned int clusters_to_del,
 580                                                struct ocfs2_dinode *fe,
 581                                                struct ocfs2_extent_list *last_el)
 582{
 583        /* for dinode + all headers in this pass + update to next leaf */
 584        u16 next_free = le16_to_cpu(last_el->l_next_free_rec);
 585        u16 tree_depth = le16_to_cpu(fe->id2.i_list.l_tree_depth);
 586        int credits = 1 + tree_depth + 1;
 587        int i;
 588
 589        i = next_free - 1;
 590        BUG_ON(i < 0);
 591
 592        /* We may be deleting metadata blocks, so metadata alloc dinode +
 593           one desc. block for each possible delete. */
 594        if (tree_depth && next_free == 1 &&
 595            ocfs2_rec_clusters(last_el, &last_el->l_recs[i]) == clusters_to_del)
 596                credits += 1 + tree_depth;
 597
 598        /* update to the truncate log. */
 599        credits += OCFS2_TRUNCATE_LOG_UPDATE;
 600
 601        credits += ocfs2_quota_trans_credits(sb);
 602
 603        return credits;
 604}
 605
 606static inline int ocfs2_jbd2_file_inode(handle_t *handle, struct inode *inode)
 607{
 608        return jbd2_journal_file_inode(handle, &OCFS2_I(inode)->ip_jinode);
 609}
 610
 611static inline int ocfs2_begin_ordered_truncate(struct inode *inode,
 612                                               loff_t new_size)
 613{
 614        return jbd2_journal_begin_ordered_truncate(
 615                                OCFS2_SB(inode->i_sb)->journal->j_journal,
 616                                &OCFS2_I(inode)->ip_jinode,
 617                                new_size);
 618}
 619
 620#endif /* OCFS2_JOURNAL_H */
 621