[deliverable/linux.git] / fs / ext4 / ext4_jbd2.h

/*
 * ext4_jbd2.h
 *
 * Written by Stephen C. Tweedie <sct@redhat.com>, 1999
 *
 * Copyright 1998--1999 Red Hat corp --- All Rights Reserved
 *
 * This file is part of the Linux kernel and is made available under
 * the terms of the GNU General Public License, version 2, or at your
 * option, any later version, incorporated herein by reference.
 *
 * Ext4-specific journaling extensions.
 */

#ifndef _EXT4_JBD2_H
#define _EXT4_JBD2_H

#include <linux/fs.h>
#include <linux/jbd2.h>
#include "ext4.h"

#define EXT4_JOURNAL(inode)	(EXT4_SB((inode)->i_sb)->s_journal)

/* Define the number of blocks we need to account to a transaction to
 * modify one block of data.
 *
 * We may have to touch one inode, one bitmap buffer, up to three
 * indirection blocks, the group and superblock summaries, and the data
 * block to complete the transaction.
 *
 * For extents-enabled fs we may have to allocate and modify up to
 * 5 levels of tree, data block (for each of these we need bitmap + group
 * summaries), root which is stored in the inode, sb
 */

#define EXT4_SINGLEDATA_TRANS_BLOCKS(sb)				\
	(EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)   \
	 ? 20U : 8U)

/* Extended attribute operations touch at most two data buffers,
 * two bitmap buffers, and two group summaries, in addition to the inode
 * and the superblock, which are already accounted for. */

#define EXT4_XATTR_TRANS_BLOCKS		6U

/* Define the minimum size for a transaction which modifies data.  This
 * needs to take into account the fact that we may end up modifying two
 * quota files too (one for the group, one for the user quota).  The
 * superblock only gets updated once, of course, so don't bother
 * counting that again for the quota updates. */

#define EXT4_DATA_TRANS_BLOCKS(sb)	(EXT4_SINGLEDATA_TRANS_BLOCKS(sb) + \
					 EXT4_XATTR_TRANS_BLOCKS - 2 + \
					 EXT4_MAXQUOTAS_TRANS_BLOCKS(sb))

/*
 * Define the number of metadata blocks we need to account to modify data.
 *
 * This include super block, inode block, quota blocks and xattr blocks
 */
#define EXT4_META_TRANS_BLOCKS(sb)	(EXT4_XATTR_TRANS_BLOCKS + \
					EXT4_MAXQUOTAS_TRANS_BLOCKS(sb))

/* Define an arbitrary limit for the amount of data we will anticipate
 * writing to any given transaction.  For unbounded transactions such as
 * write(2) and truncate(2) we can write more than this, but we always
 * start off at the maximum transaction size and grow the transaction
 * optimistically as we go. */

#define EXT4_MAX_TRANS_DATA		64U

/* We break up a large truncate or write transaction once the handle's
 * buffer credits gets this low, we need either to extend the
 * transaction or to start a new one.  Reserve enough space here for
 * inode, bitmap, superblock, group and indirection updates for at least
 * one block, plus two quota updates.  Quota allocations are not
 * needed. */

#define EXT4_RESERVE_TRANS_BLOCKS	12U

#define EXT4_INDEX_EXTRA_TRANS_BLOCKS	8

#ifdef CONFIG_QUOTA
/* Amount of blocks needed for quota update - we know that the structure was
 * allocated so we need to update only data block */
#define EXT4_QUOTA_TRANS_BLOCKS(sb) ((test_opt(sb, QUOTA) ||\
		EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA)) ?\
		1 : 0)
/* Amount of blocks needed for quota insert/delete - we do some block writes
 * but inode, sb and group updates are done only once */
#define EXT4_QUOTA_INIT_BLOCKS(sb) ((test_opt(sb, QUOTA) ||\
		EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA)) ?\
		(DQUOT_INIT_ALLOC*(EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)\
		 +3+DQUOT_INIT_REWRITE) : 0)

#define EXT4_QUOTA_DEL_BLOCKS(sb) ((test_opt(sb, QUOTA) ||\
		EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA)) ?\
		(DQUOT_DEL_ALLOC*(EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)\
		 +3+DQUOT_DEL_REWRITE) : 0)
#else
#define EXT4_QUOTA_TRANS_BLOCKS(sb) 0
#define EXT4_QUOTA_INIT_BLOCKS(sb) 0
#define EXT4_QUOTA_DEL_BLOCKS(sb) 0
#endif
#define EXT4_MAXQUOTAS_TRANS_BLOCKS(sb) (EXT4_MAXQUOTAS*EXT4_QUOTA_TRANS_BLOCKS(sb))
#define EXT4_MAXQUOTAS_INIT_BLOCKS(sb) (EXT4_MAXQUOTAS*EXT4_QUOTA_INIT_BLOCKS(sb))
#define EXT4_MAXQUOTAS_DEL_BLOCKS(sb) (EXT4_MAXQUOTAS*EXT4_QUOTA_DEL_BLOCKS(sb))

static inline int ext4_jbd2_credits_xattr(struct inode *inode)
{
	int credits = EXT4_DATA_TRANS_BLOCKS(inode->i_sb);

	/*
	 * In case of inline data, we may push out the data to a block,
	 * so we need to reserve credits for this eventuality
	 */
	if (ext4_has_inline_data(inode))
		credits += ext4_writepage_trans_blocks(inode) + 1;
	return credits;
}


/*
 * Ext4 handle operation types -- for logging purposes
 */
#define EXT4_HT_MISC             0
#define EXT4_HT_INODE            1
#define EXT4_HT_WRITE_PAGE       2
#define EXT4_HT_MAP_BLOCKS       3
#define EXT4_HT_DIR              4
#define EXT4_HT_TRUNCATE         5
#define EXT4_HT_QUOTA            6
#define EXT4_HT_RESIZE           7
#define EXT4_HT_MIGRATE          8
#define EXT4_HT_MOVE_EXTENTS     9
#define EXT4_HT_XATTR           10
#define EXT4_HT_EXT_CONVERT     11
#define EXT4_HT_MAX             12

/**
 *   struct ext4_journal_cb_entry - Base structure for callback information.
 *
 *   This struct is a 'seed' structure for a using with your own callback
 *   structs. If you are using callbacks you must allocate one of these
 *   or another struct of your own definition which has this struct
 *   as it's first element and pass it to ext4_journal_callback_add().
 */
struct ext4_journal_cb_entry {
	/* list information for other callbacks attached to the same handle */
	struct list_head jce_list;

	/*  Function to call with this callback structure */
	void (*jce_func)(struct super_block *sb,
			 struct ext4_journal_cb_entry *jce, int error);

	/* user data goes here */
};

/**
 * ext4_journal_callback_add: add a function to call after transaction commit
 * @handle: active journal transaction handle to register callback on
 * @func: callback function to call after the transaction has committed:
 *        @sb: superblock of current filesystem for transaction
 *        @jce: returned journal callback data
 *        @rc: journal state at commit (0 = transaction committed properly)
 * @jce: journal callback data (internal and function private data struct)
 *
 * The registered function will be called in the context of the journal thread
 * after the transaction for which the handle was created has completed.
 *
 * No locks are held when the callback function is called, so it is safe to
 * call blocking functions from within the callback, but the callback should
 * not block or run for too long, or the filesystem will be blocked waiting for
 * the next transaction to commit. No journaling functions can be used, or
 * there is a risk of deadlock.
 *
 * There is no guaranteed calling order of multiple registered callbacks on
 * the same transaction.
 */
static inline void ext4_journal_callback_add(handle_t *handle,
			void (*func)(struct super_block *sb,
				     struct ext4_journal_cb_entry *jce,
				     int rc),
			struct ext4_journal_cb_entry *jce)
{
	struct ext4_sb_info *sbi =
			EXT4_SB(handle->h_transaction->t_journal->j_private);

	/* Add the jce to transaction's private list */
	jce->jce_func = func;
	spin_lock(&sbi->s_md_lock);
	list_add_tail(&jce->jce_list, &handle->h_transaction->t_private_list);
	spin_unlock(&sbi->s_md_lock);
}

/**
 * ext4_journal_callback_del: delete a registered callback
 * @handle: active journal transaction handle on which callback was registered
 * @jce: registered journal callback entry to unregister
 * Return true if object was successfully removed
 */
static inline bool ext4_journal_callback_try_del(handle_t *handle,
					     struct ext4_journal_cb_entry *jce)
{
	bool deleted;
	struct ext4_sb_info *sbi =
			EXT4_SB(handle->h_transaction->t_journal->j_private);

	spin_lock(&sbi->s_md_lock);
	deleted = !list_empty(&jce->jce_list);
	list_del_init(&jce->jce_list);
	spin_unlock(&sbi->s_md_lock);
	return deleted;
}

int
ext4_mark_iloc_dirty(handle_t *handle,
		     struct inode *inode,
		     struct ext4_iloc *iloc);

/*
 * On success, We end up with an outstanding reference count against
 * iloc->bh.  This _must_ be cleaned up later.
 */

int ext4_reserve_inode_write(handle_t *handle, struct inode *inode,
			struct ext4_iloc *iloc);

int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode);

/*
 * Wrapper functions with which ext4 calls into JBD.
 */
int __ext4_journal_get_write_access(const char *where, unsigned int line,
				    handle_t *handle, struct buffer_head *bh);

int __ext4_forget(const char *where, unsigned int line, handle_t *handle,
		  int is_metadata, struct inode *inode,
		  struct buffer_head *bh, ext4_fsblk_t blocknr);

int __ext4_journal_get_create_access(const char *where, unsigned int line,
				handle_t *handle, struct buffer_head *bh);

int __ext4_handle_dirty_metadata(const char *where, unsigned int line,
				 handle_t *handle, struct inode *inode,
				 struct buffer_head *bh);

int __ext4_handle_dirty_super(const char *where, unsigned int line,
			      handle_t *handle, struct super_block *sb);

#define ext4_journal_get_write_access(handle, bh) \
	__ext4_journal_get_write_access(__func__, __LINE__, (handle), (bh))
#define ext4_forget(handle, is_metadata, inode, bh, block_nr) \
	__ext4_forget(__func__, __LINE__, (handle), (is_metadata), (inode), \
		      (bh), (block_nr))
#define ext4_journal_get_create_access(handle, bh) \
	__ext4_journal_get_create_access(__func__, __LINE__, (handle), (bh))
#define ext4_handle_dirty_metadata(handle, inode, bh) \
	__ext4_handle_dirty_metadata(__func__, __LINE__, (handle), (inode), \
				     (bh))
#define ext4_handle_dirty_super(handle, sb) \
	__ext4_handle_dirty_super(__func__, __LINE__, (handle), (sb))

handle_t *__ext4_journal_start_sb(struct super_block *sb, unsigned int line,
				  int type, int blocks, int rsv_blocks);
int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle);

#define EXT4_NOJOURNAL_MAX_REF_COUNT ((unsigned long) 4096)

/* Note:  Do not use this for NULL handles.  This is only to determine if
 * a properly allocated handle is using a journal or not. */
static inline int ext4_handle_valid(handle_t *handle)
{
	if ((unsigned long)handle < EXT4_NOJOURNAL_MAX_REF_COUNT)
		return 0;
	return 1;
}

static inline void ext4_handle_sync(handle_t *handle)
{
	if (ext4_handle_valid(handle))
		handle->h_sync = 1;
}

static inline int ext4_handle_is_aborted(handle_t *handle)
{
	if (ext4_handle_valid(handle))
		return is_handle_aborted(handle);
	return 0;
}

static inline int ext4_handle_has_enough_credits(handle_t *handle, int needed)
{
	if (ext4_handle_valid(handle) && handle->h_buffer_credits < needed)
		return 0;
	return 1;
}

#define ext4_journal_start_sb(sb, type, nblocks)			\
	__ext4_journal_start_sb((sb), __LINE__, (type), (nblocks), 0)

#define ext4_journal_start(inode, type, nblocks)			\
	__ext4_journal_start((inode), __LINE__, (type), (nblocks), 0)

#define ext4_journal_start_with_reserve(inode, type, blocks, rsv_blocks) \
	__ext4_journal_start((inode), __LINE__, (type), (blocks), (rsv_blocks))

static inline handle_t *__ext4_journal_start(struct inode *inode,
					     unsigned int line, int type,
					     int blocks, int rsv_blocks)
{
	return __ext4_journal_start_sb(inode->i_sb, line, type, blocks,
				       rsv_blocks);
}

#define ext4_journal_stop(handle) \
	__ext4_journal_stop(__func__, __LINE__, (handle))

#define ext4_journal_start_reserved(handle, type) \
	__ext4_journal_start_reserved((handle), __LINE__, (type))

handle_t *__ext4_journal_start_reserved(handle_t *handle, unsigned int line,
					int type);

static inline void ext4_journal_free_reserved(handle_t *handle)
{
	if (ext4_handle_valid(handle))
		jbd2_journal_free_reserved(handle);
}

static inline handle_t *ext4_journal_current_handle(void)
{
	return journal_current_handle();
}

static inline int ext4_journal_extend(handle_t *handle, int nblocks)
{
	if (ext4_handle_valid(handle))
		return jbd2_journal_extend(handle, nblocks);
	return 0;
}

static inline int ext4_journal_restart(handle_t *handle, int nblocks)
{
	if (ext4_handle_valid(handle))
		return jbd2_journal_restart(handle, nblocks);
	return 0;
}

static inline int ext4_journal_blocks_per_page(struct inode *inode)
{
	if (EXT4_JOURNAL(inode) != NULL)
		return jbd2_journal_blocks_per_page(inode);
	return 0;
}

static inline int ext4_journal_force_commit(journal_t *journal)
{
	if (journal)
		return jbd2_journal_force_commit(journal);
	return 0;
}

static inline int ext4_jbd2_file_inode(handle_t *handle, struct inode *inode)
{
	if (ext4_handle_valid(handle))
		return jbd2_journal_file_inode(handle, EXT4_I(inode)->jinode);
	return 0;
}

static inline void ext4_update_inode_fsync_trans(handle_t *handle,
						 struct inode *inode,
						 int datasync)
{
	struct ext4_inode_info *ei = EXT4_I(inode);

	if (ext4_handle_valid(handle)) {
		ei->i_sync_tid = handle->h_transaction->t_tid;
		if (datasync)
			ei->i_datasync_tid = handle->h_transaction->t_tid;
	}
}

/* super.c */
int ext4_force_commit(struct super_block *sb);

/*
 * Ext4 inode journal modes
 */
#define EXT4_INODE_JOURNAL_DATA_MODE	0x01 /* journal data mode */
#define EXT4_INODE_ORDERED_DATA_MODE	0x02 /* ordered data mode */
#define EXT4_INODE_WRITEBACK_DATA_MODE	0x04 /* writeback data mode */

static inline int ext4_inode_journal_mode(struct inode *inode)
{
	if (EXT4_JOURNAL(inode) == NULL)
		return EXT4_INODE_WRITEBACK_DATA_MODE;	/* writeback */
	/* We do not support data journalling with delayed allocation */
	if (!S_ISREG(inode->i_mode) ||
	    test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
		return EXT4_INODE_JOURNAL_DATA_MODE;	/* journal data */
	if (ext4_test_inode_flag(inode, EXT4_INODE_JOURNAL_DATA) &&
	    !test_opt(inode->i_sb, DELALLOC))
		return EXT4_INODE_JOURNAL_DATA_MODE;	/* journal data */
	if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
		return EXT4_INODE_ORDERED_DATA_MODE;	/* ordered */
	if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
		return EXT4_INODE_WRITEBACK_DATA_MODE;	/* writeback */
	else
		BUG();
}

static inline int ext4_should_journal_data(struct inode *inode)
{
	return ext4_inode_journal_mode(inode) & EXT4_INODE_JOURNAL_DATA_MODE;
}

static inline int ext4_should_order_data(struct inode *inode)
{
	return ext4_inode_journal_mode(inode) & EXT4_INODE_ORDERED_DATA_MODE;
}

static inline int ext4_should_writeback_data(struct inode *inode)
{
	return ext4_inode_journal_mode(inode) & EXT4_INODE_WRITEBACK_DATA_MODE;
}

/*
 * This function controls whether or not we should try to go down the
 * dioread_nolock code paths, which makes it safe to avoid taking
 * i_mutex for direct I/O reads.  This only works for extent-based
 * files, and it doesn't work if data journaling is enabled, since the
 * dioread_nolock code uses b_private to pass information back to the
 * I/O completion handler, and this conflicts with the jbd's use of
 * b_private.
 */
static inline int ext4_should_dioread_nolock(struct inode *inode)
{
	if (!test_opt(inode->i_sb, DIOREAD_NOLOCK))
		return 0;
	if (!S_ISREG(inode->i_mode))
		return 0;
	if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
		return 0;
	if (ext4_should_journal_data(inode))
		return 0;
	return 1;
}

#endif	/* _EXT4_JBD2_H */
Commit	Line	Data
470decc6	1	/*
3dcf5451	2	* ext4_jbd2.h
470decc6 DK	3	*
	4	* Written by Stephen C. Tweedie <sct@redhat.com>, 1999
	5	*
	6	* Copyright 1998--1999 Red Hat corp --- All Rights Reserved
	7	*
	8	* This file is part of the Linux kernel and is made available under
	9	* the terms of the GNU General Public License, version 2, or at your
	10	* option, any later version, incorporated herein by reference.
	11	*
	12	* Ext4-specific journaling extensions.
	13	*/
	14
3dcf5451 CH	15	#ifndef _EXT4_JBD2_H
3dcf5451 CH	16	#define _EXT4_JBD2_H
470decc6 DK	17
470decc6 DK	18	#include <linux/fs.h>
f7f4bccb	19	#include <linux/jbd2.h>
3dcf5451	20	#include "ext4.h"
470decc6 DK	21
	22	#define EXT4_JOURNAL(inode) (EXT4_SB((inode)->i_sb)->s_journal)
	23
	24	/* Define the number of blocks we need to account to a transaction to
	25	* modify one block of data.
	26	*
	27	* We may have to touch one inode, one bitmap buffer, up to three
	28	* indirection blocks, the group and superblock summaries, and the data
a86c6181 AT	29	* block to complete the transaction.
a86c6181 AT	30	*
d0d856e8	31	* For extents-enabled fs we may have to allocate and modify up to
f45a5ef9 JK	32	* 5 levels of tree, data block (for each of these we need bitmap + group
	33	* summaries), root which is stored in the inode, sb
	34	*/
470decc6	35
a86c6181	36	#define EXT4_SINGLEDATA_TRANS_BLOCKS(sb) \
83982b6f	37	(EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS) \
f45a5ef9	38	? 20U : 8U)
470decc6 DK	39
	40	/* Extended attribute operations touch at most two data buffers,
	41	* two bitmap buffers, and two group summaries, in addition to the inode
	42	* and the superblock, which are already accounted for. */
	43
	44	#define EXT4_XATTR_TRANS_BLOCKS 6U
	45
	46	/* Define the minimum size for a transaction which modifies data. This
	47	* needs to take into account the fact that we may end up modifying two
	48	* quota files too (one for the group, one for the user quota). The
	49	* superblock only gets updated once, of course, so don't bother
	50	* counting that again for the quota updates. */
	51
a86c6181	52	#define EXT4_DATA_TRANS_BLOCKS(sb) (EXT4_SINGLEDATA_TRANS_BLOCKS(sb) + \
470decc6	53	EXT4_XATTR_TRANS_BLOCKS - 2 + \
5aca07eb	54	EXT4_MAXQUOTAS_TRANS_BLOCKS(sb))
470decc6	55
a02908f1 MC	56	/*
	57	* Define the number of metadata blocks we need to account to modify data.
	58	*
	59	* This include super block, inode block, quota blocks and xattr blocks
	60	*/
	61	#define EXT4_META_TRANS_BLOCKS(sb) (EXT4_XATTR_TRANS_BLOCKS + \
5aca07eb	62	EXT4_MAXQUOTAS_TRANS_BLOCKS(sb))
a02908f1	63
470decc6 DK	64	/* Define an arbitrary limit for the amount of data we will anticipate
	65	* writing to any given transaction. For unbounded transactions such as
	66	* write(2) and truncate(2) we can write more than this, but we always
	67	* start off at the maximum transaction size and grow the transaction
	68	* optimistically as we go. */
	69
	70	#define EXT4_MAX_TRANS_DATA 64U
	71
	72	/* We break up a large truncate or write transaction once the handle's
	73	* buffer credits gets this low, we need either to extend the
	74	* transaction or to start a new one. Reserve enough space here for
	75	* inode, bitmap, superblock, group and indirection updates for at least
	76	* one block, plus two quota updates. Quota allocations are not
	77	* needed. */
	78
	79	#define EXT4_RESERVE_TRANS_BLOCKS 12U
	80
	81	#define EXT4_INDEX_EXTRA_TRANS_BLOCKS 8
	82
	83	#ifdef CONFIG_QUOTA
	84	/* Amount of blocks needed for quota update - we know that the structure was
21f97697	85	* allocated so we need to update only data block */
7c319d32 AK	86	#define EXT4_QUOTA_TRANS_BLOCKS(sb) ((test_opt(sb, QUOTA) \|\|\
	87	EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA)) ?\
	88	1 : 0)
470decc6 DK	89	/* Amount of blocks needed for quota insert/delete - we do some block writes
470decc6 DK	90	* but inode, sb and group updates are done only once */
7c319d32 AK	91	#define EXT4_QUOTA_INIT_BLOCKS(sb) ((test_opt(sb, QUOTA) \|\|\
	92	EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA)) ?\
	93	(DQUOT_INIT_ALLOC*(EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)\
	94	+3+DQUOT_INIT_REWRITE) : 0)
	95
	96	#define EXT4_QUOTA_DEL_BLOCKS(sb) ((test_opt(sb, QUOTA) \|\|\
	97	EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA)) ?\
	98	(DQUOT_DEL_ALLOC*(EXT4_SINGLEDATA_TRANS_BLOCKS(sb)-3)\
	99	+3+DQUOT_DEL_REWRITE) : 0)
470decc6 DK	100	#else
	101	#define EXT4_QUOTA_TRANS_BLOCKS(sb) 0
	102	#define EXT4_QUOTA_INIT_BLOCKS(sb) 0
	103	#define EXT4_QUOTA_DEL_BLOCKS(sb) 0
	104	#endif
a2d4a646 JK	105	#define EXT4_MAXQUOTAS_TRANS_BLOCKS(sb) (EXT4_MAXQUOTAS*EXT4_QUOTA_TRANS_BLOCKS(sb))
	106	#define EXT4_MAXQUOTAS_INIT_BLOCKS(sb) (EXT4_MAXQUOTAS*EXT4_QUOTA_INIT_BLOCKS(sb))
	107	#define EXT4_MAXQUOTAS_DEL_BLOCKS(sb) (EXT4_MAXQUOTAS*EXT4_QUOTA_DEL_BLOCKS(sb))
470decc6	108
95eaefbd TT	109	static inline int ext4_jbd2_credits_xattr(struct inode *inode)
	110	{
	111	int credits = EXT4_DATA_TRANS_BLOCKS(inode->i_sb);
	112
	113	/*
	114	* In case of inline data, we may push out the data to a block,
	115	* so we need to reserve credits for this eventuality
	116	*/
	117	if (ext4_has_inline_data(inode))
	118	credits += ext4_writepage_trans_blocks(inode) + 1;
	119	return credits;
	120	}
	121
	122
9924a92a TT	123	/*
	124	* Ext4 handle operation types -- for logging purposes
	125	*/
	126	#define EXT4_HT_MISC 0
	127	#define EXT4_HT_INODE 1
	128	#define EXT4_HT_WRITE_PAGE 2
	129	#define EXT4_HT_MAP_BLOCKS 3
	130	#define EXT4_HT_DIR 4
	131	#define EXT4_HT_TRUNCATE 5
	132	#define EXT4_HT_QUOTA 6
	133	#define EXT4_HT_RESIZE 7
	134	#define EXT4_HT_MIGRATE 8
	135	#define EXT4_HT_MOVE_EXTENTS 9
	136	#define EXT4_HT_XATTR 10
6b523df4 JK	137	#define EXT4_HT_EXT_CONVERT 11
6b523df4 JK	138	#define EXT4_HT_MAX 12
9924a92a	139
18aadd47 BJ	140	/**
	141	* struct ext4_journal_cb_entry - Base structure for callback information.
	142	*
	143	* This struct is a 'seed' structure for a using with your own callback
	144	* structs. If you are using callbacks you must allocate one of these
	145	* or another struct of your own definition which has this struct
	146	* as it's first element and pass it to ext4_journal_callback_add().
	147	*/
	148	struct ext4_journal_cb_entry {
	149	/* list information for other callbacks attached to the same handle */
	150	struct list_head jce_list;
	151
	152	/* Function to call with this callback structure */
	153	void (jce_func)(struct super_block sb,
	154	struct ext4_journal_cb_entry *jce, int error);
	155
	156	/* user data goes here */
	157	};
	158
	159	/**
	160	* ext4_journal_callback_add: add a function to call after transaction commit
	161	* @handle: active journal transaction handle to register callback on
	162	* @func: callback function to call after the transaction has committed:
	163	* @sb: superblock of current filesystem for transaction
	164	* @jce: returned journal callback data
	165	* @rc: journal state at commit (0 = transaction committed properly)
	166	* @jce: journal callback data (internal and function private data struct)
	167	*
	168	* The registered function will be called in the context of the journal thread
	169	* after the transaction for which the handle was created has completed.
	170	*
	171	* No locks are held when the callback function is called, so it is safe to
	172	* call blocking functions from within the callback, but the callback should
	173	* not block or run for too long, or the filesystem will be blocked waiting for
	174	* the next transaction to commit. No journaling functions can be used, or
	175	* there is a risk of deadlock.
	176	*
	177	* There is no guaranteed calling order of multiple registered callbacks on
	178	* the same transaction.
	179	*/
	180	static inline void ext4_journal_callback_add(handle_t *handle,
	181	void (func)(struct super_block sb,
	182	struct ext4_journal_cb_entry *jce,
	183	int rc),
	184	struct ext4_journal_cb_entry *jce)
	185	{
	186	struct ext4_sb_info *sbi =
	187	EXT4_SB(handle->h_transaction->t_journal->j_private);
	188
	189	/* Add the jce to transaction's private list */
	190	jce->jce_func = func;
	191	spin_lock(&sbi->s_md_lock);
	192	list_add_tail(&jce->jce_list, &handle->h_transaction->t_private_list);
	193	spin_unlock(&sbi->s_md_lock);
	194	}
	195
	196	/**
	197	* ext4_journal_callback_del: delete a registered callback
	198	* @handle: active journal transaction handle on which callback was registered
	199	* @jce: registered journal callback entry to unregister
70261f56	200	* Return true if object was successfully removed
18aadd47	201	*/
5d3ee208	202	static inline bool ext4_journal_callback_try_del(handle_t *handle,
18aadd47 BJ	203	struct ext4_journal_cb_entry *jce)
18aadd47 BJ	204	{
5d3ee208	205	bool deleted;
18aadd47 BJ	206	struct ext4_sb_info *sbi =
	207	EXT4_SB(handle->h_transaction->t_journal->j_private);
	208
	209	spin_lock(&sbi->s_md_lock);
5d3ee208	210	deleted = !list_empty(&jce->jce_list);
18aadd47 BJ	211	list_del_init(&jce->jce_list);
18aadd47 BJ	212	spin_unlock(&sbi->s_md_lock);
5d3ee208	213	return deleted;
18aadd47 BJ	214	}
18aadd47 BJ	215
470decc6 DK	216	int
	217	ext4_mark_iloc_dirty(handle_t *handle,
	218	struct inode *inode,
	219	struct ext4_iloc *iloc);
	220
	221	/*
	222	* On success, We end up with an outstanding reference count against
	223	* iloc->bh. This _must_ be cleaned up later.
	224	*/
	225
	226	int ext4_reserve_inode_write(handle_t handle, struct inode inode,
	227	struct ext4_iloc *iloc);
	228
	229	int ext4_mark_inode_dirty(handle_t handle, struct inode inode);
	230
	231	/*
e4684b3f	232	* Wrapper functions with which ext4 calls into JBD.
470decc6	233	*/
90c7201b TT	234	int __ext4_journal_get_write_access(const char *where, unsigned int line,
90c7201b TT	235	handle_t handle, struct buffer_head bh);
470decc6	236
90c7201b TT	237	int __ext4_forget(const char where, unsigned int line, handle_t handle,
	238	int is_metadata, struct inode *inode,
	239	struct buffer_head *bh, ext4_fsblk_t blocknr);
d6797d14	240
90c7201b	241	int __ext4_journal_get_create_access(const char *where, unsigned int line,
8984d137	242	handle_t handle, struct buffer_head bh);
470decc6	243
90c7201b TT	244	int __ext4_handle_dirty_metadata(const char *where, unsigned int line,
	245	handle_t handle, struct inode inode,
	246	struct buffer_head *bh);
470decc6	247
90c7201b	248	int __ext4_handle_dirty_super(const char *where, unsigned int line,
b50924c2	249	handle_t handle, struct super_block sb);
a0375156	250
470decc6	251	#define ext4_journal_get_write_access(handle, bh) \
90c7201b	252	__ext4_journal_get_write_access(__func__, __LINE__, (handle), (bh))
d6797d14	253	#define ext4_forget(handle, is_metadata, inode, bh, block_nr) \
90c7201b TT	254	__ext4_forget(__func__, __LINE__, (handle), (is_metadata), (inode), \
90c7201b TT	255	(bh), (block_nr))
470decc6	256	#define ext4_journal_get_create_access(handle, bh) \
90c7201b	257	__ext4_journal_get_create_access(__func__, __LINE__, (handle), (bh))
0390131b	258	#define ext4_handle_dirty_metadata(handle, inode, bh) \
90c7201b TT	259	__ext4_handle_dirty_metadata(__func__, __LINE__, (handle), (inode), \
90c7201b TT	260	(bh))
a0375156	261	#define ext4_handle_dirty_super(handle, sb) \
b50924c2	262	__ext4_handle_dirty_super(__func__, __LINE__, (handle), (sb))
470decc6	263
9924a92a	264	handle_t __ext4_journal_start_sb(struct super_block sb, unsigned int line,
5fe2fe89	265	int type, int blocks, int rsv_blocks);
c398eda0	266	int __ext4_journal_stop(const char where, unsigned int line, handle_t handle);
470decc6	267
d3d1faf6	268	#define EXT4_NOJOURNAL_MAX_REF_COUNT ((unsigned long) 4096)
0390131b	269
d3d1faf6 CW	270	/* Note: Do not use this for NULL handles. This is only to determine if
d3d1faf6 CW	271	* a properly allocated handle is using a journal or not. */
0390131b FM	272	static inline int ext4_handle_valid(handle_t *handle)
0390131b FM	273	{
d3d1faf6	274	if ((unsigned long)handle < EXT4_NOJOURNAL_MAX_REF_COUNT)
0390131b FM	275	return 0;
	276	return 1;
	277	}
	278
	279	static inline void ext4_handle_sync(handle_t *handle)
	280	{
	281	if (ext4_handle_valid(handle))
	282	handle->h_sync = 1;
	283	}
	284
0390131b FM	285	static inline int ext4_handle_is_aborted(handle_t *handle)
	286	{
	287	if (ext4_handle_valid(handle))
	288	return is_handle_aborted(handle);
	289	return 0;
	290	}
	291
	292	static inline int ext4_handle_has_enough_credits(handle_t *handle, int needed)
	293	{
	294	if (ext4_handle_valid(handle) && handle->h_buffer_credits < needed)
	295	return 0;
	296	return 1;
	297	}
	298
9924a92a	299	#define ext4_journal_start_sb(sb, type, nblocks) \
5fe2fe89	300	__ext4_journal_start_sb((sb), __LINE__, (type), (nblocks), 0)
9924a92a TT	301
9924a92a TT	302	#define ext4_journal_start(inode, type, nblocks) \
5fe2fe89 JK	303	__ext4_journal_start((inode), __LINE__, (type), (nblocks), 0)
	304
	305	#define ext4_journal_start_with_reserve(inode, type, blocks, rsv_blocks) \
	306	__ext4_journal_start((inode), __LINE__, (type), (blocks), (rsv_blocks))
9924a92a TT	307
	308	static inline handle_t __ext4_journal_start(struct inode inode,
	309	unsigned int line, int type,
5fe2fe89	310	int blocks, int rsv_blocks)
470decc6	311	{
5fe2fe89 JK	312	return __ext4_journal_start_sb(inode->i_sb, line, type, blocks,
5fe2fe89 JK	313	rsv_blocks);
470decc6 DK	314	}
	315
	316	#define ext4_journal_stop(handle) \
c398eda0	317	__ext4_journal_stop(__func__, __LINE__, (handle))
470decc6	318
6b523df4	319	#define ext4_journal_start_reserved(handle, type) \
5fe2fe89 JK	320	__ext4_journal_start_reserved((handle), __LINE__, (type))
	321
	322	handle_t __ext4_journal_start_reserved(handle_t handle, unsigned int line,
	323	int type);
	324
	325	static inline void ext4_journal_free_reserved(handle_t *handle)
	326	{
	327	if (ext4_handle_valid(handle))
	328	jbd2_journal_free_reserved(handle);
	329	}
	330
470decc6 DK	331	static inline handle_t *ext4_journal_current_handle(void)
	332	{
	333	return journal_current_handle();
	334	}
	335
	336	static inline int ext4_journal_extend(handle_t *handle, int nblocks)
	337	{
0390131b FM	338	if (ext4_handle_valid(handle))
	339	return jbd2_journal_extend(handle, nblocks);
	340	return 0;
470decc6 DK	341	}
	342
	343	static inline int ext4_journal_restart(handle_t *handle, int nblocks)
	344	{
0390131b FM	345	if (ext4_handle_valid(handle))
	346	return jbd2_journal_restart(handle, nblocks);
	347	return 0;
470decc6 DK	348	}
	349
	350	static inline int ext4_journal_blocks_per_page(struct inode *inode)
	351	{
0390131b FM	352	if (EXT4_JOURNAL(inode) != NULL)
	353	return jbd2_journal_blocks_per_page(inode);
	354	return 0;
470decc6 DK	355	}
	356
	357	static inline int ext4_journal_force_commit(journal_t *journal)
	358	{
0390131b FM	359	if (journal)
	360	return jbd2_journal_force_commit(journal);
	361	return 0;
470decc6 DK	362	}
470decc6 DK	363
678aaf48 JK	364	static inline int ext4_jbd2_file_inode(handle_t handle, struct inode inode)
678aaf48 JK	365	{
0390131b	366	if (ext4_handle_valid(handle))
8aefcd55	367	return jbd2_journal_file_inode(handle, EXT4_I(inode)->jinode);
0390131b	368	return 0;
678aaf48 JK	369	}
678aaf48 JK	370
b436b9be JK	371	static inline void ext4_update_inode_fsync_trans(handle_t *handle,
	372	struct inode *inode,
	373	int datasync)
	374	{
	375	struct ext4_inode_info *ei = EXT4_I(inode);
	376
	377	if (ext4_handle_valid(handle)) {
	378	ei->i_sync_tid = handle->h_transaction->t_tid;
	379	if (datasync)
	380	ei->i_datasync_tid = handle->h_transaction->t_tid;
	381	}
	382	}
	383
470decc6 DK	384	/* super.c */
	385	int ext4_force_commit(struct super_block *sb);
	386
3d2b1582 LC	387	/*
	388	* Ext4 inode journal modes
	389	*/
	390	#define EXT4_INODE_JOURNAL_DATA_MODE 0x01 /* journal data mode */
	391	#define EXT4_INODE_ORDERED_DATA_MODE 0x02 /* ordered data mode */
	392	#define EXT4_INODE_WRITEBACK_DATA_MODE 0x04 /* writeback data mode */
	393
	394	static inline int ext4_inode_journal_mode(struct inode *inode)
470decc6	395	{
0390131b	396	if (EXT4_JOURNAL(inode) == NULL)
3d2b1582 LC	397	return EXT4_INODE_WRITEBACK_DATA_MODE; /* writeback */
	398	/* We do not support data journalling with delayed allocation */
	399	if (!S_ISREG(inode->i_mode) \|\|
	400	test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
	401	return EXT4_INODE_JOURNAL_DATA_MODE; /* journal data */
	402	if (ext4_test_inode_flag(inode, EXT4_INODE_JOURNAL_DATA) &&
	403	!test_opt(inode->i_sb, DELALLOC))
	404	return EXT4_INODE_JOURNAL_DATA_MODE; /* journal data */
	405	if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
	406	return EXT4_INODE_ORDERED_DATA_MODE; /* ordered */
	407	if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
	408	return EXT4_INODE_WRITEBACK_DATA_MODE; /* writeback */
	409	else
	410	BUG();
	411	}
	412
	413	static inline int ext4_should_journal_data(struct inode *inode)
	414	{
	415	return ext4_inode_journal_mode(inode) & EXT4_INODE_JOURNAL_DATA_MODE;
470decc6 DK	416	}
	417
	418	static inline int ext4_should_order_data(struct inode *inode)
	419	{
3d2b1582	420	return ext4_inode_journal_mode(inode) & EXT4_INODE_ORDERED_DATA_MODE;
470decc6 DK	421	}
	422
	423	static inline int ext4_should_writeback_data(struct inode *inode)
	424	{
3d2b1582	425	return ext4_inode_journal_mode(inode) & EXT4_INODE_WRITEBACK_DATA_MODE;
470decc6 DK	426	}
470decc6 DK	427
744692dc JZ	428	/*
	429	* This function controls whether or not we should try to go down the
	430	* dioread_nolock code paths, which makes it safe to avoid taking
	431	* i_mutex for direct I/O reads. This only works for extent-based
206f7ab4 CH	432	* files, and it doesn't work if data journaling is enabled, since the
	433	* dioread_nolock code uses b_private to pass information back to the
	434	* I/O completion handler, and this conflicts with the jbd's use of
	435	* b_private.
744692dc JZ	436	*/
	437	static inline int ext4_should_dioread_nolock(struct inode *inode)
	438	{
	439	if (!test_opt(inode->i_sb, DIOREAD_NOLOCK))
	440	return 0;
744692dc JZ	441	if (!S_ISREG(inode->i_mode))
744692dc JZ	442	return 0;
12e9b892	443	if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
744692dc JZ	444	return 0;
	445	if (ext4_should_journal_data(inode))
	446	return 0;
	447	return 1;
	448	}
	449
3dcf5451	450	#endif /* _EXT4_JBD2_H */