xref: /openbmc/linux/fs/xfs/xfs_trans_priv.h (revision d3964221)
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 struct xfs_ail;
26 struct xfs_log_vec;
27 
28 
29 void	xfs_trans_init(struct xfs_mount *);
30 void	xfs_trans_add_item(struct xfs_trans *, struct xfs_log_item *);
31 void	xfs_trans_del_item(struct xfs_log_item *);
32 void	xfs_trans_free_items(struct xfs_trans *tp, xfs_lsn_t commit_lsn,
33 				bool abort);
34 void	xfs_trans_unreserve_and_mod_sb(struct xfs_trans *tp);
35 
36 void	xfs_trans_committed_bulk(struct xfs_ail *ailp, struct xfs_log_vec *lv,
37 				xfs_lsn_t commit_lsn, int aborted);
38 /*
39  * AIL traversal cursor.
40  *
41  * Rather than using a generation number for detecting changes in the ail, use
42  * a cursor that is protected by the ail lock. The aild cursor exists in the
43  * struct xfs_ail, but other traversals can declare it on the stack and link it
44  * to the ail list.
45  *
46  * When an object is deleted from or moved int the AIL, the cursor list is
47  * searched to see if the object is a designated cursor item. If it is, it is
48  * deleted from the cursor so that the next time the cursor is used traversal
49  * will return to the start.
50  *
51  * This means a traversal colliding with a removal will cause a restart of the
52  * list scan, rather than any insertion or deletion anywhere in the list. The
53  * low bit of the item pointer is set if the cursor has been invalidated so
54  * that we can tell the difference between invalidation and reaching the end
55  * of the list to trigger traversal restarts.
56  */
57 struct xfs_ail_cursor {
58 	struct list_head	list;
59 	struct xfs_log_item	*item;
60 };
61 
62 /*
63  * Private AIL structures.
64  *
65  * Eventually we need to drive the locking in here as well.
66  */
67 struct xfs_ail {
68 	struct xfs_mount	*xa_mount;
69 	struct task_struct	*xa_task;
70 	struct list_head	xa_ail;
71 	xfs_lsn_t		xa_target;
72 	xfs_lsn_t		xa_target_prev;
73 	struct list_head	xa_cursors;
74 	spinlock_t		xa_lock;
75 	xfs_lsn_t		xa_last_pushed_lsn;
76 	int			xa_log_flush;
77 	struct list_head	xa_buf_list;
78 	wait_queue_head_t	xa_empty;
79 };
80 
81 /*
82  * From xfs_trans_ail.c
83  */
84 void	xfs_trans_ail_update_bulk(struct xfs_ail *ailp,
85 				struct xfs_ail_cursor *cur,
86 				struct xfs_log_item **log_items, int nr_items,
87 				xfs_lsn_t lsn) __releases(ailp->xa_lock);
88 /*
89  * Return a pointer to the first item in the AIL.  If the AIL is empty, then
90  * return NULL.
91  */
92 static inline struct xfs_log_item *
93 xfs_ail_min(
94 	struct xfs_ail  *ailp)
95 {
96 	return list_first_entry_or_null(&ailp->xa_ail, struct xfs_log_item,
97 					li_ail);
98 }
99 
100 static inline void
101 xfs_trans_ail_update(
102 	struct xfs_ail		*ailp,
103 	struct xfs_log_item	*lip,
104 	xfs_lsn_t		lsn) __releases(ailp->xa_lock)
105 {
106 	xfs_trans_ail_update_bulk(ailp, NULL, &lip, 1, lsn);
107 }
108 
109 bool xfs_ail_delete_one(struct xfs_ail *ailp, struct xfs_log_item *lip);
110 void xfs_trans_ail_delete(struct xfs_ail *ailp, struct xfs_log_item *lip,
111 		int shutdown_type) __releases(ailp->xa_lock);
112 
113 static inline void
114 xfs_trans_ail_remove(
115 	struct xfs_log_item	*lip,
116 	int			shutdown_type)
117 {
118 	struct xfs_ail		*ailp = lip->li_ailp;
119 
120 	spin_lock(&ailp->xa_lock);
121 	/* xfs_trans_ail_delete() drops the AIL lock */
122 	if (lip->li_flags & XFS_LI_IN_AIL)
123 		xfs_trans_ail_delete(ailp, lip, shutdown_type);
124 	else
125 		spin_unlock(&ailp->xa_lock);
126 }
127 
128 void			xfs_ail_push(struct xfs_ail *, xfs_lsn_t);
129 void			xfs_ail_push_all(struct xfs_ail *);
130 void			xfs_ail_push_all_sync(struct xfs_ail *);
131 struct xfs_log_item	*xfs_ail_min(struct xfs_ail  *ailp);
132 xfs_lsn_t		xfs_ail_min_lsn(struct xfs_ail *ailp);
133 
134 struct xfs_log_item *	xfs_trans_ail_cursor_first(struct xfs_ail *ailp,
135 					struct xfs_ail_cursor *cur,
136 					xfs_lsn_t lsn);
137 struct xfs_log_item *	xfs_trans_ail_cursor_last(struct xfs_ail *ailp,
138 					struct xfs_ail_cursor *cur,
139 					xfs_lsn_t lsn);
140 struct xfs_log_item *	xfs_trans_ail_cursor_next(struct xfs_ail *ailp,
141 					struct xfs_ail_cursor *cur);
142 void			xfs_trans_ail_cursor_done(struct xfs_ail_cursor *cur);
143 
144 #if BITS_PER_LONG != 64
145 static inline void
146 xfs_trans_ail_copy_lsn(
147 	struct xfs_ail	*ailp,
148 	xfs_lsn_t	*dst,
149 	xfs_lsn_t	*src)
150 {
151 	ASSERT(sizeof(xfs_lsn_t) == 8);	/* don't lock if it shrinks */
152 	spin_lock(&ailp->xa_lock);
153 	*dst = *src;
154 	spin_unlock(&ailp->xa_lock);
155 }
156 #else
157 static inline void
158 xfs_trans_ail_copy_lsn(
159 	struct xfs_ail	*ailp,
160 	xfs_lsn_t	*dst,
161 	xfs_lsn_t	*src)
162 {
163 	ASSERT(sizeof(xfs_lsn_t) == 8);
164 	*dst = *src;
165 }
166 #endif
167 
168 static inline void
169 xfs_clear_li_failed(
170 	struct xfs_log_item	*lip)
171 {
172 	struct xfs_buf	*bp = lip->li_buf;
173 
174 	ASSERT(lip->li_flags & XFS_LI_IN_AIL);
175 	lockdep_assert_held(&lip->li_ailp->xa_lock);
176 
177 	if (lip->li_flags & XFS_LI_FAILED) {
178 		lip->li_flags &= ~XFS_LI_FAILED;
179 		lip->li_buf = NULL;
180 		xfs_buf_rele(bp);
181 	}
182 }
183 
184 static inline void
185 xfs_set_li_failed(
186 	struct xfs_log_item	*lip,
187 	struct xfs_buf		*bp)
188 {
189 	lockdep_assert_held(&lip->li_ailp->xa_lock);
190 
191 	if (!(lip->li_flags & XFS_LI_FAILED)) {
192 		xfs_buf_hold(bp);
193 		lip->li_flags |= XFS_LI_FAILED;
194 		lip->li_buf = bp;
195 	}
196 }
197 
198 #endif	/* __XFS_TRANS_PRIV_H__ */
199