[linux-2.6-block.git] / fs / xfs / xfs_trans_priv.h

/*
 * Copyright (c) 2000,2002,2005 Silicon Graphics, Inc.
 * 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.
 *
 * This program is distributed in the hope that it would 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 the Free Software Foundation,
 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
#ifndef __XFS_TRANS_PRIV_H__
#define	__XFS_TRANS_PRIV_H__

struct xfs_log_item;
struct xfs_log_item_desc;
struct xfs_mount;
struct xfs_trans;

/*
 * From xfs_trans_item.c
 */
struct xfs_log_item_desc	*xfs_trans_add_item(struct xfs_trans *,
					    struct xfs_log_item *);
void				xfs_trans_free_item(struct xfs_trans *,
					    struct xfs_log_item_desc *);
struct xfs_log_item_desc	*xfs_trans_find_item(struct xfs_trans *,
					     struct xfs_log_item *);
struct xfs_log_item_desc	*xfs_trans_first_item(struct xfs_trans *);
struct xfs_log_item_desc	*xfs_trans_next_item(struct xfs_trans *,
					     struct xfs_log_item_desc *);
void				xfs_trans_free_items(struct xfs_trans *, int);
void				xfs_trans_unlock_items(struct xfs_trans *,
							xfs_lsn_t);
void				xfs_trans_free_busy(xfs_trans_t *tp);
xfs_log_busy_slot_t		*xfs_trans_add_busy(xfs_trans_t *tp,
						    xfs_agnumber_t ag,
						    xfs_extlen_t idx);

/*
 * AIL traversal cursor.
 *
 * Rather than using a generation number for detecting changes in the ail, use
 * a cursor that is protected by the ail lock. The aild cursor exists in the
 * struct xfs_ail, but other traversals can declare it on the stack and link it
 * to the ail list.
 *
 * When an object is deleted from or moved int the AIL, the cursor list is
 * searched to see if the object is a designated cursor item. If it is, it is
 * deleted from the cursor so that the next time the cursor is used traversal
 * will return to the start.
 *
 * This means a traversal colliding with a removal will cause a restart of the
 * list scan, rather than any insertion or deletion anywhere in the list. The
 * low bit of the item pointer is set if the cursor has been invalidated so
 * that we can tell the difference between invalidation and reaching the end
 * of the list to trigger traversal restarts.
 */
struct xfs_ail_cursor {
	struct xfs_ail_cursor	*next;
	struct xfs_log_item	*item;
};

/*
 * Private AIL structures.
 *
 * Eventually we need to drive the locking in here as well.
 */
struct xfs_ail {
	struct xfs_mount	*xa_mount;
	struct list_head	xa_ail;
	uint			xa_gen;
	struct task_struct	*xa_task;
	xfs_lsn_t		xa_target;
	struct xfs_ail_cursor	xa_cursors;
	spinlock_t		xa_lock;
};

/*
 * From xfs_trans_ail.c
 */
void			xfs_trans_ail_update(struct xfs_ail *ailp,
					struct xfs_log_item *lip, xfs_lsn_t lsn)
					__releases(ailp->xa_lock);
void			xfs_trans_ail_delete(struct xfs_ail *ailp,
					struct xfs_log_item *lip)
					__releases(ailp->xa_lock);
void			xfs_trans_ail_push(struct xfs_ail *, xfs_lsn_t);
void			xfs_trans_unlocked_item(struct xfs_ail *,
					xfs_log_item_t *);

xfs_lsn_t		xfs_trans_ail_tail(struct xfs_ail *ailp);

struct xfs_log_item	*xfs_trans_ail_cursor_first(struct xfs_ail *ailp,
					struct xfs_ail_cursor *cur,
					xfs_lsn_t lsn);
struct xfs_log_item	*xfs_trans_ail_cursor_next(struct xfs_ail *ailp,
					struct xfs_ail_cursor *cur);
void			xfs_trans_ail_cursor_done(struct xfs_ail *ailp,
					struct xfs_ail_cursor *cur);

long	xfsaild_push(struct xfs_ail *, xfs_lsn_t *);
void	xfsaild_wakeup(struct xfs_ail *, xfs_lsn_t);
int	xfsaild_start(struct xfs_ail *);
void	xfsaild_stop(struct xfs_ail *);

#if BITS_PER_LONG != 64
static inline void
xfs_trans_ail_copy_lsn(
	struct xfs_ail	*ailp,
	xfs_lsn_t	*dst,
	xfs_lsn_t	*src)
{
	ASSERT(sizeof(xfs_lsn_t) == 8);	/* don't lock if it shrinks */
	spin_lock(&ailp->xa_lock);
	*dst = *src;
	spin_unlock(&ailp->xa_lock);
}
#else
static inline void
xfs_trans_ail_copy_lsn(
	struct xfs_ail	*ailp,
	xfs_lsn_t	*dst,
	xfs_lsn_t	*src)
{
	ASSERT(sizeof(xfs_lsn_t) == 8);
	*dst = *src;
}
#endif
#endif	/* __XFS_TRANS_PRIV_H__ */
Commit	Line	Data
1da177e4	1	/*
7b718769 NS	2	* Copyright (c) 2000,2002,2005 Silicon Graphics, Inc.
7b718769 NS	3	* All Rights Reserved.
1da177e4	4	*
7b718769 NS	5	* This program is free software; you can redistribute it and/or
7b718769 NS	6	* modify it under the terms of the GNU General Public License as
1da177e4 LT	7	* published by the Free Software Foundation.
1da177e4 LT	8	*
7b718769 NS	9	* This program is distributed in the hope that it would be useful,
	10	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	12	* GNU General Public License for more details.
1da177e4	13	*
7b718769 NS	14	* You should have received a copy of the GNU General Public License
	15	* along with this program; if not, write the Free Software Foundation,
	16	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
1da177e4 LT	17	*/
	18	#ifndef __XFS_TRANS_PRIV_H__
	19	#define __XFS_TRANS_PRIV_H__
	20
	21	struct xfs_log_item;
	22	struct xfs_log_item_desc;
	23	struct xfs_mount;
	24	struct xfs_trans;
	25
	26	/*
	27	* From xfs_trans_item.c
	28	*/
	29	struct xfs_log_item_desc xfs_trans_add_item(struct xfs_trans ,
	30	struct xfs_log_item *);
	31	void xfs_trans_free_item(struct xfs_trans *,
	32	struct xfs_log_item_desc *);
	33	struct xfs_log_item_desc xfs_trans_find_item(struct xfs_trans ,
	34	struct xfs_log_item *);
	35	struct xfs_log_item_desc xfs_trans_first_item(struct xfs_trans );
	36	struct xfs_log_item_desc xfs_trans_next_item(struct xfs_trans ,
	37	struct xfs_log_item_desc *);
	38	void xfs_trans_free_items(struct xfs_trans *, int);
	39	void xfs_trans_unlock_items(struct xfs_trans *,
	40	xfs_lsn_t);
	41	void xfs_trans_free_busy(xfs_trans_t *tp);
	42	xfs_log_busy_slot_t xfs_trans_add_busy(xfs_trans_t tp,
	43	xfs_agnumber_t ag,
	44	xfs_extlen_t idx);
	45
	46	/*
27d8d5fe DC	47	* AIL traversal cursor.
	48	*
	49	* Rather than using a generation number for detecting changes in the ail, use
	50	* a cursor that is protected by the ail lock. The aild cursor exists in the
	51	* struct xfs_ail, but other traversals can declare it on the stack and link it
	52	* to the ail list.
	53	*
	54	* When an object is deleted from or moved int the AIL, the cursor list is
	55	* searched to see if the object is a designated cursor item. If it is, it is
	56	* deleted from the cursor so that the next time the cursor is used traversal
	57	* will return to the start.
	58	*
	59	* This means a traversal colliding with a removal will cause a restart of the
	60	* list scan, rather than any insertion or deletion anywhere in the list. The
	61	* low bit of the item pointer is set if the cursor has been invalidated so
	62	* that we can tell the difference between invalidation and reaching the end
	63	* of the list to trigger traversal restarts.
1da177e4	64	*/
27d8d5fe DC	65	struct xfs_ail_cursor {
	66	struct xfs_ail_cursor *next;
	67	struct xfs_log_item *item;
	68	};
1da177e4	69
249a8c11	70	/*
27d8d5fe DC	71	* Private AIL structures.
	72	*
	73	* Eventually we need to drive the locking in here as well.
249a8c11	74	*/
82fa9012 DC	75	struct xfs_ail {
	76	struct xfs_mount *xa_mount;
	77	struct list_head xa_ail;
	78	uint xa_gen;
	79	struct task_struct *xa_task;
	80	xfs_lsn_t xa_target;
27d8d5fe	81	struct xfs_ail_cursor xa_cursors;
c7e8f268	82	spinlock_t xa_lock;
82fa9012 DC	83	};
82fa9012 DC	84
27d8d5fe DC	85	/*
	86	* From xfs_trans_ail.c
	87	*/
783a2f65 DC	88	void xfs_trans_ail_update(struct xfs_ail *ailp,
	89	struct xfs_log_item *lip, xfs_lsn_t lsn)
	90	__releases(ailp->xa_lock);
	91	void xfs_trans_ail_delete(struct xfs_ail *ailp,
	92	struct xfs_log_item *lip)
	93	__releases(ailp->xa_lock);
	94	void xfs_trans_ail_push(struct xfs_ail *, xfs_lsn_t);
	95	void xfs_trans_unlocked_item(struct xfs_ail *,
	96	xfs_log_item_t *);
27d8d5fe	97
5b00f14f DC	98	xfs_lsn_t xfs_trans_ail_tail(struct xfs_ail *ailp);
	99
	100	struct xfs_log_item xfs_trans_ail_cursor_first(struct xfs_ail ailp,
	101	struct xfs_ail_cursor *cur,
	102	xfs_lsn_t lsn);
	103	struct xfs_log_item xfs_trans_ail_cursor_next(struct xfs_ail ailp,
27d8d5fe	104	struct xfs_ail_cursor *cur);
5b00f14f	105	void xfs_trans_ail_cursor_done(struct xfs_ail *ailp,
27d8d5fe DC	106	struct xfs_ail_cursor *cur);
27d8d5fe DC	107
82fa9012 DC	108	long xfsaild_push(struct xfs_ail , xfs_lsn_t );
	109	void xfsaild_wakeup(struct xfs_ail *, xfs_lsn_t);
	110	int xfsaild_start(struct xfs_ail *);
	111	void xfsaild_stop(struct xfs_ail *);
249a8c11	112
7b2e2a31 DC	113	#if BITS_PER_LONG != 64
	114	static inline void
	115	xfs_trans_ail_copy_lsn(
	116	struct xfs_ail *ailp,
	117	xfs_lsn_t *dst,
	118	xfs_lsn_t *src)
	119	{
	120	ASSERT(sizeof(xfs_lsn_t) == 8); /* don't lock if it shrinks */
c7e8f268	121	spin_lock(&ailp->xa_lock);
7b2e2a31	122	dst = src;
c7e8f268	123	spin_unlock(&ailp->xa_lock);
7b2e2a31 DC	124	}
	125	#else
	126	static inline void
	127	xfs_trans_ail_copy_lsn(
	128	struct xfs_ail *ailp,
	129	xfs_lsn_t *dst,
	130	xfs_lsn_t *src)
	131	{
	132	ASSERT(sizeof(xfs_lsn_t) == 8);
	133	dst = src;
	134	}
	135	#endif
1da177e4	136	#endif /* __XFS_TRANS_PRIV_H__ */