xref: /linux/fs/xfs/xfs_log.h (revision af50e4ba34f4c45e92535364133d4deb5931c1c5)
1 /*
2  * Copyright (c) 2000-2003,2005 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_LOG_H__
19 #define __XFS_LOG_H__
20 
21 struct xfs_log_vec {
22 	struct xfs_log_vec	*lv_next;	/* next lv in build list */
23 	int			lv_niovecs;	/* number of iovecs in lv */
24 	struct xfs_log_iovec	*lv_iovecp;	/* iovec array */
25 	struct xfs_log_item	*lv_item;	/* owner */
26 	char			*lv_buf;	/* formatted buffer */
27 	int			lv_bytes;	/* accounted space in buffer */
28 	int			lv_buf_len;	/* aligned size of buffer */
29 	int			lv_size;	/* size of allocated lv */
30 };
31 
32 #define XFS_LOG_VEC_ORDERED	(-1)
33 
34 static inline void *
35 xlog_prepare_iovec(struct xfs_log_vec *lv, struct xfs_log_iovec **vecp,
36 		uint type)
37 {
38 	struct xfs_log_iovec *vec = *vecp;
39 
40 	if (vec) {
41 		ASSERT(vec - lv->lv_iovecp < lv->lv_niovecs);
42 		vec++;
43 	} else {
44 		vec = &lv->lv_iovecp[0];
45 	}
46 
47 	vec->i_type = type;
48 	vec->i_addr = lv->lv_buf + lv->lv_buf_len;
49 
50 	ASSERT(IS_ALIGNED((unsigned long)vec->i_addr, sizeof(uint64_t)));
51 
52 	*vecp = vec;
53 	return vec->i_addr;
54 }
55 
56 /*
57  * We need to make sure the next buffer is naturally aligned for the biggest
58  * basic data type we put into it.  We already accounted for this padding when
59  * sizing the buffer.
60  *
61  * However, this padding does not get written into the log, and hence we have to
62  * track the space used by the log vectors separately to prevent log space hangs
63  * due to inaccurate accounting (i.e. a leak) of the used log space through the
64  * CIL context ticket.
65  */
66 static inline void
67 xlog_finish_iovec(struct xfs_log_vec *lv, struct xfs_log_iovec *vec, int len)
68 {
69 	lv->lv_buf_len += round_up(len, sizeof(uint64_t));
70 	lv->lv_bytes += len;
71 	vec->i_len = len;
72 }
73 
74 static inline void *
75 xlog_copy_iovec(struct xfs_log_vec *lv, struct xfs_log_iovec **vecp,
76 		uint type, void *data, int len)
77 {
78 	void *buf;
79 
80 	buf = xlog_prepare_iovec(lv, vecp, type);
81 	memcpy(buf, data, len);
82 	xlog_finish_iovec(lv, *vecp, len);
83 	return buf;
84 }
85 
86 /*
87  * Structure used to pass callback function and the function's argument
88  * to the log manager.
89  */
90 typedef struct xfs_log_callback {
91 	struct xfs_log_callback	*cb_next;
92 	void			(*cb_func)(void *, int);
93 	void			*cb_arg;
94 } xfs_log_callback_t;
95 
96 /*
97  * By comparing each component, we don't have to worry about extra
98  * endian issues in treating two 32 bit numbers as one 64 bit number
99  */
100 static inline xfs_lsn_t	_lsn_cmp(xfs_lsn_t lsn1, xfs_lsn_t lsn2)
101 {
102 	if (CYCLE_LSN(lsn1) != CYCLE_LSN(lsn2))
103 		return (CYCLE_LSN(lsn1)<CYCLE_LSN(lsn2))? -999 : 999;
104 
105 	if (BLOCK_LSN(lsn1) != BLOCK_LSN(lsn2))
106 		return (BLOCK_LSN(lsn1)<BLOCK_LSN(lsn2))? -999 : 999;
107 
108 	return 0;
109 }
110 
111 #define	XFS_LSN_CMP(x,y) _lsn_cmp(x,y)
112 
113 /*
114  * Flags to xfs_log_force()
115  *
116  *	XFS_LOG_SYNC:	Synchronous force in-core log to disk
117  */
118 #define XFS_LOG_SYNC		0x1
119 
120 /* Log manager interfaces */
121 struct xfs_mount;
122 struct xlog_in_core;
123 struct xlog_ticket;
124 struct xfs_log_item;
125 struct xfs_item_ops;
126 struct xfs_trans;
127 
128 xfs_lsn_t xfs_log_done(struct xfs_mount *mp,
129 		       struct xlog_ticket *ticket,
130 		       struct xlog_in_core **iclog,
131 		       bool regrant);
132 int	  xfs_log_force(struct xfs_mount *mp, uint flags);
133 int	  xfs_log_force_lsn(struct xfs_mount *mp, xfs_lsn_t lsn, uint flags,
134 		int *log_forced);
135 int	  xfs_log_mount(struct xfs_mount	*mp,
136 			struct xfs_buftarg	*log_target,
137 			xfs_daddr_t		start_block,
138 			int		 	num_bblocks);
139 int	  xfs_log_mount_finish(struct xfs_mount *mp);
140 int	xfs_log_mount_cancel(struct xfs_mount *);
141 xfs_lsn_t xlog_assign_tail_lsn(struct xfs_mount *mp);
142 xfs_lsn_t xlog_assign_tail_lsn_locked(struct xfs_mount *mp);
143 void	  xfs_log_space_wake(struct xfs_mount *mp);
144 int	  xfs_log_notify(struct xlog_in_core	*iclog,
145 			 struct xfs_log_callback *callback_entry);
146 int	  xfs_log_release_iclog(struct xfs_mount *mp,
147 			 struct xlog_in_core	 *iclog);
148 int	  xfs_log_reserve(struct xfs_mount *mp,
149 			  int		   length,
150 			  int		   count,
151 			  struct xlog_ticket **ticket,
152 			  uint8_t		   clientid,
153 			  bool		   permanent);
154 int	  xfs_log_regrant(struct xfs_mount *mp, struct xlog_ticket *tic);
155 void      xfs_log_unmount(struct xfs_mount *mp);
156 int	  xfs_log_force_umount(struct xfs_mount *mp, int logerror);
157 
158 struct xlog_ticket *xfs_log_ticket_get(struct xlog_ticket *ticket);
159 void	  xfs_log_ticket_put(struct xlog_ticket *ticket);
160 
161 void	xfs_log_commit_cil(struct xfs_mount *mp, struct xfs_trans *tp,
162 				xfs_lsn_t *commit_lsn, bool regrant);
163 bool	xfs_log_item_in_current_chkpt(struct xfs_log_item *lip);
164 
165 void	xfs_log_work_queue(struct xfs_mount *mp);
166 void	xfs_log_quiesce(struct xfs_mount *mp);
167 bool	xfs_log_check_lsn(struct xfs_mount *, xfs_lsn_t);
168 
169 #endif	/* __XFS_LOG_H__ */
170