1/*
2 * Copyright (c) 2000,2002,2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
8 *
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.
13 *
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
17 */
18#ifndef __XFS_TRANS_PRIV_H__
19#define	__XFS_TRANS_PRIV_H__
20
21struct xfs_log_item;
22struct xfs_log_item_desc;
23struct xfs_mount;
24struct xfs_trans;
25
26void	xfs_trans_add_item(struct xfs_trans *, struct xfs_log_item *);
27void	xfs_trans_del_item(struct xfs_log_item *);
28void	xfs_trans_free_items(struct xfs_trans *tp, xfs_lsn_t commit_lsn,
29				int flags);
30void	xfs_trans_item_committed(struct xfs_log_item *lip,
31				xfs_lsn_t commit_lsn, int aborted);
32void	xfs_trans_unreserve_and_mod_sb(struct xfs_trans *tp);
33
34/*
35 * AIL traversal cursor.
36 *
37 * Rather than using a generation number for detecting changes in the ail, use
38 * a cursor that is protected by the ail lock. The aild cursor exists in the
39 * struct xfs_ail, but other traversals can declare it on the stack and link it
40 * to the ail list.
41 *
42 * When an object is deleted from or moved int the AIL, the cursor list is
43 * searched to see if the object is a designated cursor item. If it is, it is
44 * deleted from the cursor so that the next time the cursor is used traversal
45 * will return to the start.
46 *
47 * This means a traversal colliding with a removal will cause a restart of the
48 * list scan, rather than any insertion or deletion anywhere in the list. The
49 * low bit of the item pointer is set if the cursor has been invalidated so
50 * that we can tell the difference between invalidation and reaching the end
51 * of the list to trigger traversal restarts.
52 */
53struct xfs_ail_cursor {
54	struct xfs_ail_cursor	*next;
55	struct xfs_log_item	*item;
56};
57
58/*
59 * Private AIL structures.
60 *
61 * Eventually we need to drive the locking in here as well.
62 */
63struct xfs_ail {
64	struct xfs_mount	*xa_mount;
65	struct list_head	xa_ail;
66	uint			xa_gen;
67	struct task_struct	*xa_task;
68	xfs_lsn_t		xa_target;
69	struct xfs_ail_cursor	xa_cursors;
70	spinlock_t		xa_lock;
71};
72
73/*
74 * From xfs_trans_ail.c
75 */
76void			xfs_trans_ail_update(struct xfs_ail *ailp,
77					struct xfs_log_item *lip, xfs_lsn_t lsn)
78					__releases(ailp->xa_lock);
79void			xfs_trans_ail_delete(struct xfs_ail *ailp,
80					struct xfs_log_item *lip)
81					__releases(ailp->xa_lock);
82void			xfs_trans_ail_push(struct xfs_ail *, xfs_lsn_t);
83void			xfs_trans_unlocked_item(struct xfs_ail *,
84					xfs_log_item_t *);
85
86xfs_lsn_t		xfs_trans_ail_tail(struct xfs_ail *ailp);
87
88struct xfs_log_item	*xfs_trans_ail_cursor_first(struct xfs_ail *ailp,
89					struct xfs_ail_cursor *cur,
90					xfs_lsn_t lsn);
91struct xfs_log_item	*xfs_trans_ail_cursor_next(struct xfs_ail *ailp,
92					struct xfs_ail_cursor *cur);
93void			xfs_trans_ail_cursor_done(struct xfs_ail *ailp,
94					struct xfs_ail_cursor *cur);
95
96long	xfsaild_push(struct xfs_ail *, xfs_lsn_t *);
97void	xfsaild_wakeup(struct xfs_ail *, xfs_lsn_t);
98int	xfsaild_start(struct xfs_ail *);
99void	xfsaild_stop(struct xfs_ail *);
100
101#if BITS_PER_LONG != 64
102static inline void
103xfs_trans_ail_copy_lsn(
104	struct xfs_ail	*ailp,
105	xfs_lsn_t	*dst,
106	xfs_lsn_t	*src)
107{
108	ASSERT(sizeof(xfs_lsn_t) == 8);	/* don't lock if it shrinks */
109	spin_lock(&ailp->xa_lock);
110	*dst = *src;
111	spin_unlock(&ailp->xa_lock);
112}
113#else
114static inline void
115xfs_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);
121	*dst = *src;
122}
123#endif
124#endif	/* __XFS_TRANS_PRIV_H__ */
125