xref: /linux/fs/ocfs2/journal.h (revision 60e13231561b3a4c5269bfa1ef6c0569ad6f28ec)
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 
32 enum ocfs2_journal_state {
33 	OCFS2_JOURNAL_FREE = 0,
34 	OCFS2_JOURNAL_LOADED,
35 	OCFS2_JOURNAL_IN_SHUTDOWN,
36 };
37 
38 struct ocfs2_super;
39 struct 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 
46 struct ocfs2_recovery_map {
47 	unsigned int rm_used;
48 	unsigned int *rm_entries;
49 };
50 
51 
52 struct 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 
80 extern spinlock_t trans_inc_lock;
81 
82 /* wrap j_trans_id so we never have it equal to zero. */
83 static 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 
94 static 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. */
107 static 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. */
123 static 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 */
138 static 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 
149 static 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. */
158 void ocfs2_orphan_scan_init(struct ocfs2_super *osb);
159 void ocfs2_orphan_scan_start(struct ocfs2_super *osb);
160 void ocfs2_orphan_scan_stop(struct ocfs2_super *osb);
161 void ocfs2_orphan_scan_exit(struct ocfs2_super *osb);
162 
163 void ocfs2_complete_recovery(struct work_struct *work);
164 void ocfs2_wait_for_recovery(struct ocfs2_super *osb);
165 
166 int ocfs2_recovery_init(struct ocfs2_super *osb);
167 void ocfs2_recovery_exit(struct ocfs2_super *osb);
168 
169 int 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  */
186 void   ocfs2_set_journal_params(struct ocfs2_super *osb);
187 int    ocfs2_journal_init(struct ocfs2_journal *journal,
188 			  int *dirty);
189 void   ocfs2_journal_shutdown(struct ocfs2_super *osb);
190 int    ocfs2_journal_wipe(struct ocfs2_journal *journal,
191 			  int full);
192 int    ocfs2_journal_load(struct ocfs2_journal *journal, int local,
193 			  int replayed);
194 int    ocfs2_check_journals_nolocks(struct ocfs2_super *osb);
195 void   ocfs2_recovery_thread(struct ocfs2_super *osb,
196 			     int node_num);
197 int    ocfs2_mark_dead_nodes(struct ocfs2_super *osb);
198 void   ocfs2_complete_mount_recovery(struct ocfs2_super *osb);
199 void ocfs2_complete_quota_recovery(struct ocfs2_super *osb);
200 
201 static 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 
207 static 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. */
257 handle_t		    *ocfs2_start_trans(struct ocfs2_super *osb,
258 					       int max_buffs);
259 int			     ocfs2_commit_trans(struct ocfs2_super *osb,
260 						handle_t *handle);
261 int			     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 */
280 int ocfs2_journal_access_di(handle_t *handle, struct ocfs2_caching_info *ci,
281 			    struct buffer_head *bh, int type);
282 /* ocfs2_extent_block */
283 int ocfs2_journal_access_eb(handle_t *handle, struct ocfs2_caching_info *ci,
284 			    struct buffer_head *bh, int type);
285 /* ocfs2_refcount_block */
286 int ocfs2_journal_access_rb(handle_t *handle, struct ocfs2_caching_info *ci,
287 			    struct buffer_head *bh, int type);
288 /* ocfs2_group_desc */
289 int ocfs2_journal_access_gd(handle_t *handle, struct ocfs2_caching_info *ci,
290 			    struct buffer_head *bh, int type);
291 /* ocfs2_xattr_block */
292 int ocfs2_journal_access_xb(handle_t *handle, struct ocfs2_caching_info *ci,
293 			    struct buffer_head *bh, int type);
294 /* quota blocks */
295 int ocfs2_journal_access_dq(handle_t *handle, struct ocfs2_caching_info *ci,
296 			    struct buffer_head *bh, int type);
297 /* dirblock */
298 int ocfs2_journal_access_db(handle_t *handle, struct ocfs2_caching_info *ci,
299 			    struct buffer_head *bh, int type);
300 /* ocfs2_dx_root_block */
301 int ocfs2_journal_access_dr(handle_t *handle, struct ocfs2_caching_info *ci,
302 			    struct buffer_head *bh, int type);
303 /* ocfs2_dx_leaf */
304 int 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 */
307 int 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  */
329 void 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 
368 static 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 
389 static 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 
402 static 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 
412 static 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 */
423 static 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 static 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 */
453 static 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 */
467 static 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 
483 static 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  */
515 static 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 
543 static 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 
554 static 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 
565 /*
566  * Allocating a discontiguous block group requires the credits from
567  * ocfs2_calc_group_alloc_credits() as well as enough credits to fill
568  * the group descriptor's extent list.  The caller already has started
569  * the transaction with ocfs2_calc_group_alloc_credits().  They extend
570  * it with these credits.
571  */
572 static inline int ocfs2_calc_bg_discontig_credits(struct super_block *sb)
573 {
574 	return ocfs2_extent_recs_per_gd(sb);
575 }
576 
577 static inline int ocfs2_calc_tree_trunc_credits(struct super_block *sb,
578 						unsigned int clusters_to_del,
579 						struct ocfs2_dinode *fe,
580 						struct ocfs2_extent_list *last_el)
581 {
582  	/* for dinode + all headers in this pass + update to next leaf */
583 	u16 next_free = le16_to_cpu(last_el->l_next_free_rec);
584 	u16 tree_depth = le16_to_cpu(fe->id2.i_list.l_tree_depth);
585 	int credits = 1 + tree_depth + 1;
586 	int i;
587 
588 	i = next_free - 1;
589 	BUG_ON(i < 0);
590 
591 	/* We may be deleting metadata blocks, so metadata alloc dinode +
592 	   one desc. block for each possible delete. */
593 	if (tree_depth && next_free == 1 &&
594 	    ocfs2_rec_clusters(last_el, &last_el->l_recs[i]) == clusters_to_del)
595 		credits += 1 + tree_depth;
596 
597 	/* update to the truncate log. */
598 	credits += OCFS2_TRUNCATE_LOG_UPDATE;
599 
600 	credits += ocfs2_quota_trans_credits(sb);
601 
602 	return credits;
603 }
604 
605 static inline int ocfs2_jbd2_file_inode(handle_t *handle, struct inode *inode)
606 {
607 	return jbd2_journal_file_inode(handle, &OCFS2_I(inode)->ip_jinode);
608 }
609 
610 static inline int ocfs2_begin_ordered_truncate(struct inode *inode,
611 					       loff_t new_size)
612 {
613 	return jbd2_journal_begin_ordered_truncate(
614 				OCFS2_SB(inode->i_sb)->journal->j_journal,
615 				&OCFS2_I(inode)->ip_jinode,
616 				new_size);
617 }
618 
619 #endif /* OCFS2_JOURNAL_H */
620