summaryrefslogtreecommitdiff
path: root/fs/xfs/xfs_trans_priv.h
blob: 901dc0f032dae73a79a81c611f22171013be0b42 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
/*
 * 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);

/*
 * 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__ */