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
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 /*
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.
64 */
65 struct xfs_ail_cursor {
66 struct xfs_ail_cursor *next;
67 struct xfs_log_item *item;
68 };
69
70 /*
71 * Private AIL structures.
72 *
73 * Eventually we need to drive the locking in here as well.
74 */
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;
81 struct xfs_ail_cursor xa_cursors;
82 spinlock_t xa_lock;
83 };
84
85 /*
86 * From xfs_trans_ail.c
87 */
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 *);
97
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,
104 struct xfs_ail_cursor *cur);
105 void xfs_trans_ail_cursor_done(struct xfs_ail *ailp,
106 struct xfs_ail_cursor *cur);
107
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 *);
112
113 #if BITS_PER_LONG != 64
114 static inline void
xfs_trans_ail_copy_lsn(struct xfs_ail * ailp,xfs_lsn_t * dst,xfs_lsn_t * src)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 */
121 spin_lock(&ailp->xa_lock);
122 *dst = *src;
123 spin_unlock(&ailp->xa_lock);
124 }
125 #else
126 static inline void
xfs_trans_ail_copy_lsn(struct xfs_ail * ailp,xfs_lsn_t * dst,xfs_lsn_t * src)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
136 #endif /* __XFS_TRANS_PRIV_H__ */
137