[deliverable/linux.git] / fs / ocfs2 / journal.h

/* -*- mode: c; c-basic-offset: 8; -*-
 * vim: noexpandtab sw=8 ts=8 sts=0:
 *
 * journal.h
 *
 * Defines journalling api and structures.
 *
 * Copyright (C) 2003, 2005 Oracle.  All rights reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public
 * License along with this program; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 021110-1307, USA.
 */

#ifndef OCFS2_JOURNAL_H
#define OCFS2_JOURNAL_H

#include <linux/fs.h>
#include <linux/jbd.h>

enum ocfs2_journal_state {
	OCFS2_JOURNAL_FREE = 0,
	OCFS2_JOURNAL_LOADED,
	OCFS2_JOURNAL_IN_SHUTDOWN,
};

struct ocfs2_super;
struct ocfs2_dinode;

struct ocfs2_journal {
	enum ocfs2_journal_state   j_state;    /* Journals current state   */

	journal_t                 *j_journal; /* The kernels journal type */
	struct inode              *j_inode;   /* Kernel inode pointing to
					       * this journal             */
	struct ocfs2_super        *j_osb;     /* pointer to the super
					       * block for the node
					       * we're currently
					       * running on -- not
					       * necessarily the super
					       * block from the node
					       * which we usually run
					       * from (recovery,
					       * etc)                     */
	struct buffer_head        *j_bh;      /* Journal disk inode block */
	atomic_t                  j_num_trans; /* Number of transactions
					        * currently in the system. */
	unsigned long             j_trans_id;
	struct rw_semaphore       j_trans_barrier;
	wait_queue_head_t         j_checkpointed;

	spinlock_t                j_lock;
	struct list_head          j_la_cleanups;
	struct work_struct        j_recovery_work;
};

extern spinlock_t trans_inc_lock;

/* wrap j_trans_id so we never have it equal to zero. */
static inline unsigned long ocfs2_inc_trans_id(struct ocfs2_journal *j)
{
	unsigned long old_id;
	spin_lock(&trans_inc_lock);
	old_id = j->j_trans_id++;
	if (unlikely(!j->j_trans_id))
		j->j_trans_id = 1;
	spin_unlock(&trans_inc_lock);
	return old_id;
}

static inline void ocfs2_set_inode_lock_trans(struct ocfs2_journal *journal,
					      struct inode *inode)
{
	spin_lock(&trans_inc_lock);
	OCFS2_I(inode)->ip_last_trans = journal->j_trans_id;
	spin_unlock(&trans_inc_lock);
}

/* Used to figure out whether it's safe to drop a metadata lock on an
 * inode. Returns true if all the inodes changes have been
 * checkpointed to disk. You should be holding the spinlock on the
 * metadata lock while calling this to be sure that nobody can take
 * the lock and put it on another transaction. */
static inline int ocfs2_inode_fully_checkpointed(struct inode *inode)
{
	int ret;
	struct ocfs2_journal *journal = OCFS2_SB(inode->i_sb)->journal;

	spin_lock(&trans_inc_lock);
	ret = time_after(journal->j_trans_id, OCFS2_I(inode)->ip_last_trans);
	spin_unlock(&trans_inc_lock);
	return ret;
}

/* convenience function to check if an inode is still new (has never
 * hit disk) Will do you a favor and set created_trans = 0 when you've
 * been checkpointed.  returns '1' if the inode is still new. */
static inline int ocfs2_inode_is_new(struct inode *inode)
{
	int ret;

	/* System files are never "new" as they're written out by
	 * mkfs. This helps us early during mount, before we have the
	 * journal open and j_trans_id could be junk. */
	if (OCFS2_I(inode)->ip_flags & OCFS2_INODE_SYSTEM_FILE)
		return 0;
	spin_lock(&trans_inc_lock);
	ret = !(time_after(OCFS2_SB(inode->i_sb)->journal->j_trans_id,
			   OCFS2_I(inode)->ip_created_trans));
	if (!ret)
		OCFS2_I(inode)->ip_created_trans = 0;
	spin_unlock(&trans_inc_lock);
	return ret;
}

static inline void ocfs2_inode_set_new(struct ocfs2_super *osb,
				       struct inode *inode)
{
	spin_lock(&trans_inc_lock);
	OCFS2_I(inode)->ip_created_trans = osb->journal->j_trans_id;
	spin_unlock(&trans_inc_lock);
}

/* Exported only for the journal struct init code in super.c. Do not call. */
void ocfs2_complete_recovery(struct work_struct *work);
void ocfs2_wait_for_recovery(struct ocfs2_super *osb);

int ocfs2_recovery_init(struct ocfs2_super *osb);
void ocfs2_recovery_exit(struct ocfs2_super *osb);

/*
 *  Journal Control:
 *  Initialize, Load, Shutdown, Wipe a journal.
 *
 *  ocfs2_journal_init     - Initialize journal structures in the OSB.
 *  ocfs2_journal_load     - Load the given journal off disk. Replay it if
 *                          there's transactions still in there.
 *  ocfs2_journal_shutdown - Shutdown a journal, this will flush all
 *                          uncommitted, uncheckpointed transactions.
 *  ocfs2_journal_wipe     - Wipe transactions from a journal. Optionally
 *                          zero out each block.
 *  ocfs2_recovery_thread  - Perform recovery on a node. osb is our own osb.
 *  ocfs2_mark_dead_nodes - Start recovery on nodes we won't get a heartbeat
 *                          event on.
 *  ocfs2_start_checkpoint - Kick the commit thread to do a checkpoint.
 */
void   ocfs2_set_journal_params(struct ocfs2_super *osb);
int    ocfs2_journal_init(struct ocfs2_journal *journal,
			  int *dirty);
void   ocfs2_journal_shutdown(struct ocfs2_super *osb);
int    ocfs2_journal_wipe(struct ocfs2_journal *journal,
			  int full);
int    ocfs2_journal_load(struct ocfs2_journal *journal, int local,
			  int replayed);
int    ocfs2_check_journals_nolocks(struct ocfs2_super *osb);
void   ocfs2_recovery_thread(struct ocfs2_super *osb,
			     int node_num);
int    ocfs2_mark_dead_nodes(struct ocfs2_super *osb);
void   ocfs2_complete_mount_recovery(struct ocfs2_super *osb);

static inline void ocfs2_start_checkpoint(struct ocfs2_super *osb)
{
	atomic_set(&osb->needs_checkpoint, 1);
	wake_up(&osb->checkpoint_event);
}

static inline void ocfs2_checkpoint_inode(struct inode *inode)
{
	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);

	if (ocfs2_mount_local(osb))
		return;

	if (!ocfs2_inode_fully_checkpointed(inode)) {
		/* WARNING: This only kicks off a single
		 * checkpoint. If someone races you and adds more
		 * metadata to the journal, you won't know, and will
		 * wind up waiting *alot* longer than necessary. Right
		 * now we only use this in clear_inode so that's
		 * OK. */
		ocfs2_start_checkpoint(osb);

		wait_event(osb->journal->j_checkpointed,
			   ocfs2_inode_fully_checkpointed(inode));
	}
}

/*
 *  Transaction Handling:
 *  Manage the lifetime of a transaction handle.
 *
 *  ocfs2_start_trans      - Begin a transaction. Give it an upper estimate of
 *                          the number of blocks that will be changed during
 *                          this handle.
 *  ocfs2_commit_trans - Complete a handle. It might return -EIO if
 *                       the journal was aborted. The majority of paths don't
 *                       check the return value as an error there comes too
 *                       late to do anything (and will be picked up in a
 *                       later transaction).
 *  ocfs2_extend_trans     - Extend a handle by nblocks credits. This may
 *                          commit the handle to disk in the process, but will
 *                          not release any locks taken during the transaction.
 *  ocfs2_journal_access   - Notify the handle that we want to journal this
 *                          buffer. Will have to call ocfs2_journal_dirty once
 *                          we've actually dirtied it. Type is one of . or .
 *  ocfs2_journal_dirty    - Mark a journalled buffer as having dirty data.
 *  ocfs2_journal_dirty_data - Indicate that a data buffer should go out before
 *                             the current handle commits.
 */

/* You must always start_trans with a number of buffs > 0, but it's
 * perfectly legal to go through an entire transaction without having
 * dirtied any buffers. */
handle_t		    *ocfs2_start_trans(struct ocfs2_super *osb,
					       int max_buffs);
int			     ocfs2_commit_trans(struct ocfs2_super *osb,
						handle_t *handle);
int			     ocfs2_extend_trans(handle_t *handle, int nblocks);

/*
 * Create access is for when we get a newly created buffer and we're
 * not gonna read it off disk, but rather fill it ourselves.  Right
 * now, we don't do anything special with this (it turns into a write
 * request), but this is a good placeholder in case we do...
 *
 * Write access is for when we read a block off disk and are going to
 * modify it. This way the journalling layer knows it may need to make
 * a copy of that block (if it's part of another, uncommitted
 * transaction) before we do so.
 */
#define OCFS2_JOURNAL_ACCESS_CREATE 0
#define OCFS2_JOURNAL_ACCESS_WRITE  1
#define OCFS2_JOURNAL_ACCESS_UNDO   2

int                  ocfs2_journal_access(handle_t *handle,
					  struct inode *inode,
					  struct buffer_head *bh,
					  int type);
/*
 * A word about the journal_access/journal_dirty "dance". It is
 * entirely legal to journal_access a buffer more than once (as long
 * as the access type is the same -- I'm not sure what will happen if
 * access type is different but this should never happen anyway) It is
 * also legal to journal_dirty a buffer more than once. In fact, you
 * can even journal_access a buffer after you've done a
 * journal_access/journal_dirty pair. The only thing you cannot do
 * however, is journal_dirty a buffer which you haven't yet passed to
 * journal_access at least once.
 *
 * That said, 99% of the time this doesn't matter and this is what the
 * path looks like:
 *
 *	<read a bh>
 *	ocfs2_journal_access(handle, bh,	OCFS2_JOURNAL_ACCESS_WRITE);
 *	<modify the bh>
 * 	ocfs2_journal_dirty(handle, bh);
 */
int                  ocfs2_journal_dirty(handle_t *handle,
					 struct buffer_head *bh);
int                  ocfs2_journal_dirty_data(handle_t *handle,
					      struct buffer_head *bh);

/*
 *  Credit Macros:
 *  Convenience macros to calculate number of credits needed.
 *
 *  For convenience sake, I have a set of macros here which calculate
 *  the *maximum* number of sectors which will be changed for various
 *  metadata updates.
 */

/* simple file updates like chmod, etc. */
#define OCFS2_INODE_UPDATE_CREDITS 1

/* group extend. inode update and last group update. */
#define OCFS2_GROUP_EXTEND_CREDITS	(OCFS2_INODE_UPDATE_CREDITS + 1)

/* group add. inode update and the new group update. */
#define OCFS2_GROUP_ADD_CREDITS	(OCFS2_INODE_UPDATE_CREDITS + 1)

/* get one bit out of a suballocator: dinode + group descriptor +
 * prev. group desc. if we relink. */
#define OCFS2_SUBALLOC_ALLOC (3)

#define OCFS2_INLINE_TO_EXTENTS_CREDITS (OCFS2_SUBALLOC_ALLOC		\
					 + OCFS2_INODE_UPDATE_CREDITS)

/* dinode + group descriptor update. We don't relink on free yet. */
#define OCFS2_SUBALLOC_FREE  (2)

#define OCFS2_TRUNCATE_LOG_UPDATE OCFS2_INODE_UPDATE_CREDITS
#define OCFS2_TRUNCATE_LOG_FLUSH_ONE_REC (OCFS2_SUBALLOC_FREE 		      \
					 + OCFS2_TRUNCATE_LOG_UPDATE)

#define OCFS2_REMOVE_EXTENT_CREDITS (OCFS2_TRUNCATE_LOG_UPDATE + OCFS2_INODE_UPDATE_CREDITS)

/* data block for new dir/symlink, 2 for bitmap updates (bitmap fe +
 * bitmap block for the new bit) */
#define OCFS2_DIR_LINK_ADDITIONAL_CREDITS (1 + 2)

/* parent fe, parent block, new file entry, inode alloc fe, inode alloc
 * group descriptor + mkdir/symlink blocks */
#define OCFS2_MKNOD_CREDITS (3 + OCFS2_SUBALLOC_ALLOC                         \
			    + OCFS2_DIR_LINK_ADDITIONAL_CREDITS)

/* local alloc metadata change + main bitmap updates */
#define OCFS2_WINDOW_MOVE_CREDITS (OCFS2_INODE_UPDATE_CREDITS                 \
				  + OCFS2_SUBALLOC_ALLOC + OCFS2_SUBALLOC_FREE)

/* used when we don't need an allocation change for a dir extend. One
 * for the dinode, one for the new block. */
#define OCFS2_SIMPLE_DIR_EXTEND_CREDITS (2)

/* file update (nlink, etc) + directory mtime/ctime + dir entry block */
#define OCFS2_LINK_CREDITS  (2*OCFS2_INODE_UPDATE_CREDITS + 1)

/* inode + dir inode (if we unlink a dir), + dir entry block + orphan
 * dir inode link */
#define OCFS2_UNLINK_CREDITS  (2 * OCFS2_INODE_UPDATE_CREDITS + 1             \
			      + OCFS2_LINK_CREDITS)

/* dinode + orphan dir dinode + inode alloc dinode + orphan dir entry +
 * inode alloc group descriptor */
#define OCFS2_DELETE_INODE_CREDITS (3 * OCFS2_INODE_UPDATE_CREDITS + 1 + 1)

/* dinode update, old dir dinode update, new dir dinode update, old
 * dir dir entry, new dir dir entry, dir entry update for renaming
 * directory + target unlink */
#define OCFS2_RENAME_CREDITS (3 * OCFS2_INODE_UPDATE_CREDITS + 3              \
			     + OCFS2_UNLINK_CREDITS)

/*
 * Please note that the caller must make sure that root_el is the root
 * of extent tree. So for an inode, it should be &fe->id2.i_list. Otherwise
 * the result may be wrong.
 */
static inline int ocfs2_calc_extend_credits(struct super_block *sb,
					    struct ocfs2_extent_list *root_el,
					    u32 bits_wanted)
{
	int bitmap_blocks, sysfile_bitmap_blocks, extent_blocks;

	/* bitmap dinode, group desc. + relinked group. */
	bitmap_blocks = OCFS2_SUBALLOC_ALLOC;

	/* we might need to shift tree depth so lets assume an
	 * absolute worst case of complete fragmentation.  Even with
	 * that, we only need one update for the dinode, and then
	 * however many metadata chunks needed * a remaining suballoc
	 * alloc. */
	sysfile_bitmap_blocks = 1 +
		(OCFS2_SUBALLOC_ALLOC - 1) * ocfs2_extend_meta_needed(root_el);

	/* this does not include *new* metadata blocks, which are
	 * accounted for in sysfile_bitmap_blocks. root_el +
	 * prev. last_eb_blk + blocks along edge of tree.
	 * calc_symlink_credits passes because we just need 1
	 * credit for the dinode there. */
	extent_blocks = 1 + 1 + le16_to_cpu(root_el->l_tree_depth);

	return bitmap_blocks + sysfile_bitmap_blocks + extent_blocks;
}

static inline int ocfs2_calc_symlink_credits(struct super_block *sb)
{
	int blocks = OCFS2_MKNOD_CREDITS;

	/* links can be longer than one block so we may update many
	 * within our single allocated extent. */
	blocks += ocfs2_clusters_to_blocks(sb, 1);

	return blocks;
}

static inline int ocfs2_calc_group_alloc_credits(struct super_block *sb,
						 unsigned int cpg)
{
	int blocks;
	int bitmap_blocks = OCFS2_SUBALLOC_ALLOC + 1;
	/* parent inode update + new block group header + bitmap inode update
	   + bitmap blocks affected */
	blocks = 1 + 1 + 1 + bitmap_blocks;
	return blocks;
}

static inline int ocfs2_calc_tree_trunc_credits(struct super_block *sb,
						unsigned int clusters_to_del,
						struct ocfs2_dinode *fe,
						struct ocfs2_extent_list *last_el)
{
 	/* for dinode + all headers in this pass + update to next leaf */
	u16 next_free = le16_to_cpu(last_el->l_next_free_rec);
	u16 tree_depth = le16_to_cpu(fe->id2.i_list.l_tree_depth);
	int credits = 1 + tree_depth + 1;
	int i;

	i = next_free - 1;
	BUG_ON(i < 0);

	/* We may be deleting metadata blocks, so metadata alloc dinode +
	   one desc. block for each possible delete. */
	if (tree_depth && next_free == 1 &&
	    ocfs2_rec_clusters(last_el, &last_el->l_recs[i]) == clusters_to_del)
		credits += 1 + tree_depth;

	/* update to the truncate log. */
	credits += OCFS2_TRUNCATE_LOG_UPDATE;

	return credits;
}

#endif /* OCFS2_JOURNAL_H */
Commit	Line	Data
ccd979bd MF	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/jbd.h>
	31
ccd979bd MF	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;
ccd979bd MF	40
	41	struct ocfs2_journal {
	42	enum ocfs2_journal_state j_state; /* Journals current state */
	43
	44	journal_t j_journal; / The kernels journal type */
	45	struct inode j_inode; / Kernel inode pointing to
	46	* this journal */
	47	struct ocfs2_super j_osb; / pointer to the super
	48	* block for the node
	49	* we're currently
	50	* running on -- not
	51	* necessarily the super
	52	* block from the node
	53	* which we usually run
	54	* from (recovery,
	55	* etc) */
	56	struct buffer_head j_bh; / Journal disk inode block */
	57	atomic_t j_num_trans; /* Number of transactions
	58	* currently in the system. */
	59	unsigned long j_trans_id;
	60	struct rw_semaphore j_trans_barrier;
	61	wait_queue_head_t j_checkpointed;
	62
	63	spinlock_t j_lock;
	64	struct list_head j_la_cleanups;
	65	struct work_struct j_recovery_work;
	66	};
	67
	68	extern spinlock_t trans_inc_lock;
	69
	70	/* wrap j_trans_id so we never have it equal to zero. */
	71	static inline unsigned long ocfs2_inc_trans_id(struct ocfs2_journal *j)
	72	{
	73	unsigned long old_id;
	74	spin_lock(&trans_inc_lock);
	75	old_id = j->j_trans_id++;
	76	if (unlikely(!j->j_trans_id))
	77	j->j_trans_id = 1;
	78	spin_unlock(&trans_inc_lock);
	79	return old_id;
	80	}
	81
	82	static inline void ocfs2_set_inode_lock_trans(struct ocfs2_journal *journal,
	83	struct inode *inode)
	84	{
	85	spin_lock(&trans_inc_lock);
	86	OCFS2_I(inode)->ip_last_trans = journal->j_trans_id;
	87	spin_unlock(&trans_inc_lock);
	88	}
	89
	90	/* Used to figure out whether it's safe to drop a metadata lock on an
	91	* inode. Returns true if all the inodes changes have been
	92	* checkpointed to disk. You should be holding the spinlock on the
	93	* metadata lock while calling this to be sure that nobody can take
	94	* the lock and put it on another transaction. */
	95	static inline int ocfs2_inode_fully_checkpointed(struct inode *inode)
	96	{
	97	int ret;
	98	struct ocfs2_journal *journal = OCFS2_SB(inode->i_sb)->journal;
	99
	100	spin_lock(&trans_inc_lock);
	101	ret = time_after(journal->j_trans_id, OCFS2_I(inode)->ip_last_trans);
	102	spin_unlock(&trans_inc_lock);
	103	return ret;
104	}
105
106	/* convenience function to check if an inode is still new (has never
107	* hit disk) Will do you a favor and set created_trans = 0 when you've
108	* been checkpointed. returns '1' if the inode is still new. */
109	static inline int ocfs2_inode_is_new(struct inode *inode)
110	{
111	int ret;
112
113	/* System files are never "new" as they're written out by
114	* mkfs. This helps us early during mount, before we have the
115	* journal open and j_trans_id could be junk. */
116	if (OCFS2_I(inode)->ip_flags & OCFS2_INODE_SYSTEM_FILE)
117	return 0;
118	spin_lock(&trans_inc_lock);
119	ret = !(time_after(OCFS2_SB(inode->i_sb)->journal->j_trans_id,
120	OCFS2_I(inode)->ip_created_trans));
121	if (!ret)
122	OCFS2_I(inode)->ip_created_trans = 0;
123	spin_unlock(&trans_inc_lock);
124	return ret;
125	}
126
127	static inline void ocfs2_inode_set_new(struct ocfs2_super *osb,
128	struct inode *inode)
129	{
130	spin_lock(&trans_inc_lock);
131	OCFS2_I(inode)->ip_created_trans = osb->journal->j_trans_id;
132	spin_unlock(&trans_inc_lock);
133	}
134
ccd979bd	135	/* Exported only for the journal struct init code in super.c. Do not call. */
c4028958	136	void ocfs2_complete_recovery(struct work_struct *work);
553abd04 JB	137	void ocfs2_wait_for_recovery(struct ocfs2_super *osb);
	138
	139	int ocfs2_recovery_init(struct ocfs2_super *osb);
	140	void ocfs2_recovery_exit(struct ocfs2_super *osb);
ccd979bd MF	141
	142	/*
	143	* Journal Control:
	144	* Initialize, Load, Shutdown, Wipe a journal.
	145	*
	146	* ocfs2_journal_init - Initialize journal structures in the OSB.
	147	* ocfs2_journal_load - Load the given journal off disk. Replay it if
	148	* there's transactions still in there.
	149	* ocfs2_journal_shutdown - Shutdown a journal, this will flush all
	150	* uncommitted, uncheckpointed transactions.
	151	* ocfs2_journal_wipe - Wipe transactions from a journal. Optionally
	152	* zero out each block.
	153	* ocfs2_recovery_thread - Perform recovery on a node. osb is our own osb.
	154	* ocfs2_mark_dead_nodes - Start recovery on nodes we won't get a heartbeat
	155	* event on.
	156	* ocfs2_start_checkpoint - Kick the commit thread to do a checkpoint.
	157	*/
	158	void ocfs2_set_journal_params(struct ocfs2_super *osb);
	159	int ocfs2_journal_init(struct ocfs2_journal *journal,
	160	int *dirty);
	161	void ocfs2_journal_shutdown(struct ocfs2_super *osb);
	162	int ocfs2_journal_wipe(struct ocfs2_journal *journal,
	163	int full);
539d8264 SM	164	int ocfs2_journal_load(struct ocfs2_journal *journal, int local,
539d8264 SM	165	int replayed);
ccd979bd MF	166	int ocfs2_check_journals_nolocks(struct ocfs2_super *osb);
	167	void ocfs2_recovery_thread(struct ocfs2_super *osb,
	168	int node_num);
	169	int ocfs2_mark_dead_nodes(struct ocfs2_super *osb);
	170	void ocfs2_complete_mount_recovery(struct ocfs2_super *osb);
	171
	172	static inline void ocfs2_start_checkpoint(struct ocfs2_super *osb)
	173	{
	174	atomic_set(&osb->needs_checkpoint, 1);
	175	wake_up(&osb->checkpoint_event);
	176	}
	177
	178	static inline void ocfs2_checkpoint_inode(struct inode *inode)
	179	{
	180	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
	181
c271c5c2 SM	182	if (ocfs2_mount_local(osb))
	183	return;
	184
ccd979bd MF	185	if (!ocfs2_inode_fully_checkpointed(inode)) {
	186	/* WARNING: This only kicks off a single
	187	* checkpoint. If someone races you and adds more
	188	* metadata to the journal, you won't know, and will
	189	* wind up waiting alot longer than necessary. Right
	190	* now we only use this in clear_inode so that's
	191	* OK. */
	192	ocfs2_start_checkpoint(osb);
	193
	194	wait_event(osb->journal->j_checkpointed,
	195	ocfs2_inode_fully_checkpointed(inode));
	196	}
	197	}
	198
	199	/*
	200	* Transaction Handling:
	201	* Manage the lifetime of a transaction handle.
	202	*
ccd979bd MF	203	* ocfs2_start_trans - Begin a transaction. Give it an upper estimate of
	204	* the number of blocks that will be changed during
	205	* this handle.
1fabe148 MF	206	* ocfs2_commit_trans - Complete a handle. It might return -EIO if
	207	* the journal was aborted. The majority of paths don't
	208	* check the return value as an error there comes too
	209	* late to do anything (and will be picked up in a
	210	* later transaction).
ccd979bd MF	211	* ocfs2_extend_trans - Extend a handle by nblocks credits. This may
	212	* commit the handle to disk in the process, but will
	213	* not release any locks taken during the transaction.
	214	* ocfs2_journal_access - Notify the handle that we want to journal this
	215	* buffer. Will have to call ocfs2_journal_dirty once
	216	* we've actually dirtied it. Type is one of . or .
	217	* ocfs2_journal_dirty - Mark a journalled buffer as having dirty data.
	218	* ocfs2_journal_dirty_data - Indicate that a data buffer should go out before
	219	* the current handle commits.
ccd979bd MF	220	*/
	221
	222	/* You must always start_trans with a number of buffs > 0, but it's
	223	* perfectly legal to go through an entire transaction without having
	224	* dirtied any buffers. */
1fabe148	225	handle_t ocfs2_start_trans(struct ocfs2_super osb,
ccd979bd	226	int max_buffs);
1fabe148 MF	227	int ocfs2_commit_trans(struct ocfs2_super *osb,
1fabe148 MF	228	handle_t *handle);
1fc58146	229	int ocfs2_extend_trans(handle_t *handle, int nblocks);
ccd979bd MF	230
	231	/*
	232	* Create access is for when we get a newly created buffer and we're
	233	* not gonna read it off disk, but rather fill it ourselves. Right
	234	* now, we don't do anything special with this (it turns into a write
	235	* request), but this is a good placeholder in case we do...
	236	*
	237	* Write access is for when we read a block off disk and are going to
	238	* modify it. This way the journalling layer knows it may need to make
	239	* a copy of that block (if it's part of another, uncommitted
	240	* transaction) before we do so.
	241	*/
	242	#define OCFS2_JOURNAL_ACCESS_CREATE 0
	243	#define OCFS2_JOURNAL_ACCESS_WRITE 1
	244	#define OCFS2_JOURNAL_ACCESS_UNDO 2
	245
1fabe148	246	int ocfs2_journal_access(handle_t *handle,
ccd979bd MF	247	struct inode *inode,
	248	struct buffer_head *bh,
	249	int type);
	250	/*
	251	* A word about the journal_access/journal_dirty "dance". It is
	252	* entirely legal to journal_access a buffer more than once (as long
	253	* as the access type is the same -- I'm not sure what will happen if
	254	* access type is different but this should never happen anyway) It is
	255	* also legal to journal_dirty a buffer more than once. In fact, you
	256	* can even journal_access a buffer after you've done a
	257	* journal_access/journal_dirty pair. The only thing you cannot do
	258	* however, is journal_dirty a buffer which you haven't yet passed to
	259	* journal_access at least once.
	260	*
	261	* That said, 99% of the time this doesn't matter and this is what the
	262	* path looks like:
	263	*
	264	* <read a bh>
	265	* ocfs2_journal_access(handle, bh, OCFS2_JOURNAL_ACCESS_WRITE);
	266	* <modify the bh>
	267	* ocfs2_journal_dirty(handle, bh);
	268	*/
1fabe148	269	int ocfs2_journal_dirty(handle_t *handle,
ccd979bd MF	270	struct buffer_head *bh);
	271	int ocfs2_journal_dirty_data(handle_t *handle,
	272	struct buffer_head *bh);
ccd979bd MF	273
	274	/*
	275	* Credit Macros:
	276	* Convenience macros to calculate number of credits needed.
	277	*
	278	* For convenience sake, I have a set of macros here which calculate
	279	* the maximum number of sectors which will be changed for various
	280	* metadata updates.
	281	*/
	282
	283	/* simple file updates like chmod, etc. */
	284	#define OCFS2_INODE_UPDATE_CREDITS 1
	285
d659072f TM	286	/* group extend. inode update and last group update. */
	287	#define OCFS2_GROUP_EXTEND_CREDITS (OCFS2_INODE_UPDATE_CREDITS + 1)
	288
7909f2bf TM	289	/* group add. inode update and the new group update. */
	290	#define OCFS2_GROUP_ADD_CREDITS (OCFS2_INODE_UPDATE_CREDITS + 1)
	291
ccd979bd MF	292	/* get one bit out of a suballocator: dinode + group descriptor +
	293	* prev. group desc. if we relink. */
	294	#define OCFS2_SUBALLOC_ALLOC (3)
	295
1afc32b9 MF	296	#define OCFS2_INLINE_TO_EXTENTS_CREDITS (OCFS2_SUBALLOC_ALLOC \
	297	+ OCFS2_INODE_UPDATE_CREDITS)
	298
ccd979bd MF	299	/* dinode + group descriptor update. We don't relink on free yet. */
	300	#define OCFS2_SUBALLOC_FREE (2)
	301
	302	#define OCFS2_TRUNCATE_LOG_UPDATE OCFS2_INODE_UPDATE_CREDITS
	303	#define OCFS2_TRUNCATE_LOG_FLUSH_ONE_REC (OCFS2_SUBALLOC_FREE \
	304	+ OCFS2_TRUNCATE_LOG_UPDATE)
	305
063c4561 MF	306	#define OCFS2_REMOVE_EXTENT_CREDITS (OCFS2_TRUNCATE_LOG_UPDATE + OCFS2_INODE_UPDATE_CREDITS)
063c4561 MF	307
ccd979bd MF	308	/* data block for new dir/symlink, 2 for bitmap updates (bitmap fe +
	309	* bitmap block for the new bit) */
	310	#define OCFS2_DIR_LINK_ADDITIONAL_CREDITS (1 + 2)
	311
	312	/* parent fe, parent block, new file entry, inode alloc fe, inode alloc
	313	* group descriptor + mkdir/symlink blocks */
	314	#define OCFS2_MKNOD_CREDITS (3 + OCFS2_SUBALLOC_ALLOC \
	315	+ OCFS2_DIR_LINK_ADDITIONAL_CREDITS)
	316
	317	/* local alloc metadata change + main bitmap updates */
	318	#define OCFS2_WINDOW_MOVE_CREDITS (OCFS2_INODE_UPDATE_CREDITS \
	319	+ OCFS2_SUBALLOC_ALLOC + OCFS2_SUBALLOC_FREE)
	320
	321	/* used when we don't need an allocation change for a dir extend. One
	322	* for the dinode, one for the new block. */
	323	#define OCFS2_SIMPLE_DIR_EXTEND_CREDITS (2)
	324
e051fda4 MF	325	/* file update (nlink, etc) + directory mtime/ctime + dir entry block */
e051fda4 MF	326	#define OCFS2_LINK_CREDITS (2*OCFS2_INODE_UPDATE_CREDITS + 1)
ccd979bd MF	327
	328	/* inode + dir inode (if we unlink a dir), + dir entry block + orphan
	329	* dir inode link */
	330	#define OCFS2_UNLINK_CREDITS (2 * OCFS2_INODE_UPDATE_CREDITS + 1 \
	331	+ OCFS2_LINK_CREDITS)
	332
	333	/* dinode + orphan dir dinode + inode alloc dinode + orphan dir entry +
	334	* inode alloc group descriptor */
	335	#define OCFS2_DELETE_INODE_CREDITS (3 * OCFS2_INODE_UPDATE_CREDITS + 1 + 1)
	336
	337	/* dinode update, old dir dinode update, new dir dinode update, old
	338	* dir dir entry, new dir dir entry, dir entry update for renaming
	339	* directory + target unlink */
	340	#define OCFS2_RENAME_CREDITS (3 * OCFS2_INODE_UPDATE_CREDITS + 3 \
	341	+ OCFS2_UNLINK_CREDITS)
	342
811f933d TM	343	/*
	344	* Please note that the caller must make sure that root_el is the root
	345	* of extent tree. So for an inode, it should be &fe->id2.i_list. Otherwise
	346	* the result may be wrong.
	347	*/
ccd979bd	348	static inline int ocfs2_calc_extend_credits(struct super_block *sb,
811f933d	349	struct ocfs2_extent_list *root_el,
ccd979bd MF	350	u32 bits_wanted)
ccd979bd MF	351	{
811f933d	352	int bitmap_blocks, sysfile_bitmap_blocks, extent_blocks;
ccd979bd MF	353
	354	/* bitmap dinode, group desc. + relinked group. */
	355	bitmap_blocks = OCFS2_SUBALLOC_ALLOC;
	356
	357	/* we might need to shift tree depth so lets assume an
	358	* absolute worst case of complete fragmentation. Even with
	359	* that, we only need one update for the dinode, and then
	360	* however many metadata chunks needed * a remaining suballoc
	361	* alloc. */
	362	sysfile_bitmap_blocks = 1 +
811f933d	363	(OCFS2_SUBALLOC_ALLOC - 1) * ocfs2_extend_meta_needed(root_el);
ccd979bd MF	364
ccd979bd MF	365	/* this does not include new metadata blocks, which are
811f933d	366	* accounted for in sysfile_bitmap_blocks. root_el +
ccd979bd MF	367	* prev. last_eb_blk + blocks along edge of tree.
	368	* calc_symlink_credits passes because we just need 1
	369	* credit for the dinode there. */
811f933d	370	extent_blocks = 1 + 1 + le16_to_cpu(root_el->l_tree_depth);
ccd979bd	371
811f933d	372	return bitmap_blocks + sysfile_bitmap_blocks + extent_blocks;
ccd979bd MF	373	}
	374
	375	static inline int ocfs2_calc_symlink_credits(struct super_block *sb)
	376	{
	377	int blocks = OCFS2_MKNOD_CREDITS;
	378
	379	/* links can be longer than one block so we may update many
	380	* within our single allocated extent. */
	381	blocks += ocfs2_clusters_to_blocks(sb, 1);
	382
	383	return blocks;
	384	}
	385
	386	static inline int ocfs2_calc_group_alloc_credits(struct super_block *sb,
	387	unsigned int cpg)
	388	{
	389	int blocks;
	390	int bitmap_blocks = OCFS2_SUBALLOC_ALLOC + 1;
	391	/* parent inode update + new block group header + bitmap inode update
	392	+ bitmap blocks affected */
	393	blocks = 1 + 1 + 1 + bitmap_blocks;
	394	return blocks;
	395	}
	396
	397	static inline int ocfs2_calc_tree_trunc_credits(struct super_block *sb,
	398	unsigned int clusters_to_del,
	399	struct ocfs2_dinode *fe,
	400	struct ocfs2_extent_list *last_el)
	401	{
	402	/* for dinode + all headers in this pass + update to next leaf */
	403	u16 next_free = le16_to_cpu(last_el->l_next_free_rec);
	404	u16 tree_depth = le16_to_cpu(fe->id2.i_list.l_tree_depth);
	405	int credits = 1 + tree_depth + 1;
	406	int i;
	407
	408	i = next_free - 1;
	409	BUG_ON(i < 0);
	410
	411	/* We may be deleting metadata blocks, so metadata alloc dinode +
	412	one desc. block for each possible delete. */
	413	if (tree_depth && next_free == 1 &&
e48edee2	414	ocfs2_rec_clusters(last_el, &last_el->l_recs[i]) == clusters_to_del)
ccd979bd MF	415	credits += 1 + tree_depth;
	416
	417	/* update to the truncate log. */
	418	credits += OCFS2_TRUNCATE_LOG_UPDATE;
	419
	420	return credits;
	421	}
	422
	423	#endif /* OCFS2_JOURNAL_H */