xref: /linux/fs/xfs/xfs_log.h (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
4  * All Rights Reserved.
5  */
6 #ifndef	__XFS_LOG_H__
7 #define __XFS_LOG_H__
8 
9 struct xfs_cil_ctx;
10 
11 struct xfs_log_vec {
12 	struct list_head	lv_list;	/* CIL lv chain ptrs */
13 	uint32_t		lv_order_id;	/* chain ordering info */
14 	int			lv_niovecs;	/* number of iovecs in lv */
15 	struct xfs_log_iovec	*lv_iovecp;	/* iovec array */
16 	struct xfs_log_item	*lv_item;	/* owner */
17 	char			*lv_buf;	/* formatted buffer */
18 	int			lv_bytes;	/* accounted space in buffer */
19 	int			lv_buf_len;	/* aligned size of buffer */
20 	int			lv_size;	/* size of allocated lv */
21 };
22 
23 #define XFS_LOG_VEC_ORDERED	(-1)
24 
25 /*
26  * Calculate the log iovec length for a given user buffer length. Intended to be
27  * used by ->iop_size implementations when sizing buffers of arbitrary
28  * alignments.
29  */
30 static inline int
31 xlog_calc_iovec_len(int len)
32 {
33 	return roundup(len, sizeof(uint32_t));
34 }
35 
36 void *xlog_prepare_iovec(struct xfs_log_vec *lv, struct xfs_log_iovec **vecp,
37 		uint type);
38 
39 static inline void
40 xlog_finish_iovec(struct xfs_log_vec *lv, struct xfs_log_iovec *vec,
41 		int data_len)
42 {
43 	struct xlog_op_header	*oph = vec->i_addr;
44 	int			len;
45 
46 	/*
47 	 * Always round up the length to the correct alignment so callers don't
48 	 * need to know anything about this log vec layout requirement. This
49 	 * means we have to zero the area the data to be written does not cover.
50 	 * This is complicated by fact the payload region is offset into the
51 	 * logvec region by the opheader that tracks the payload.
52 	 */
53 	len = xlog_calc_iovec_len(data_len);
54 	if (len - data_len != 0) {
55 		char	*buf = vec->i_addr + sizeof(struct xlog_op_header);
56 
57 		memset(buf + data_len, 0, len - data_len);
58 	}
59 
60 	/*
61 	 * The opheader tracks aligned payload length, whilst the logvec tracks
62 	 * the overall region length.
63 	 */
64 	oph->oh_len = cpu_to_be32(len);
65 
66 	len += sizeof(struct xlog_op_header);
67 	lv->lv_buf_len += len;
68 	lv->lv_bytes += len;
69 	vec->i_len = len;
70 
71 	/* Catch buffer overruns */
72 	ASSERT((void *)lv->lv_buf + lv->lv_bytes <= (void *)lv + lv->lv_size);
73 }
74 
75 /*
76  * Copy the amount of data requested by the caller into a new log iovec.
77  */
78 static inline void *
79 xlog_copy_iovec(struct xfs_log_vec *lv, struct xfs_log_iovec **vecp,
80 		uint type, void *data, int len)
81 {
82 	void *buf;
83 
84 	buf = xlog_prepare_iovec(lv, vecp, type);
85 	memcpy(buf, data, len);
86 	xlog_finish_iovec(lv, *vecp, len);
87 	return buf;
88 }
89 
90 static inline void *
91 xlog_copy_from_iovec(struct xfs_log_vec *lv, struct xfs_log_iovec **vecp,
92 		const struct xfs_log_iovec *src)
93 {
94 	return xlog_copy_iovec(lv, vecp, src->i_type, src->i_addr, src->i_len);
95 }
96 
97 /*
98  * By comparing each component, we don't have to worry about extra
99  * endian issues in treating two 32 bit numbers as one 64 bit number
100  */
101 static inline xfs_lsn_t	_lsn_cmp(xfs_lsn_t lsn1, xfs_lsn_t lsn2)
102 {
103 	if (CYCLE_LSN(lsn1) != CYCLE_LSN(lsn2))
104 		return (CYCLE_LSN(lsn1)<CYCLE_LSN(lsn2))? -999 : 999;
105 
106 	if (BLOCK_LSN(lsn1) != BLOCK_LSN(lsn2))
107 		return (BLOCK_LSN(lsn1)<BLOCK_LSN(lsn2))? -999 : 999;
108 
109 	return 0;
110 }
111 
112 #define	XFS_LSN_CMP(x,y) _lsn_cmp(x,y)
113 
114 /*
115  * Flags to xfs_log_force()
116  *
117  *	XFS_LOG_SYNC:	Synchronous force in-core log to disk
118  */
119 #define XFS_LOG_SYNC		0x1
120 
121 /* Log manager interfaces */
122 struct xfs_mount;
123 struct xlog_in_core;
124 struct xlog_ticket;
125 struct xfs_log_item;
126 struct xfs_item_ops;
127 struct xfs_trans;
128 struct xlog;
129 
130 int	  xfs_log_force(struct xfs_mount *mp, uint flags);
131 int	  xfs_log_force_seq(struct xfs_mount *mp, xfs_csn_t seq, uint flags,
132 		int *log_forced);
133 int	  xfs_log_mount(struct xfs_mount	*mp,
134 			struct xfs_buftarg	*log_target,
135 			xfs_daddr_t		start_block,
136 			int		 	num_bblocks);
137 int	  xfs_log_mount_finish(struct xfs_mount *mp);
138 void	xfs_log_mount_cancel(struct xfs_mount *);
139 xfs_lsn_t xlog_assign_tail_lsn(struct xfs_mount *mp);
140 xfs_lsn_t xlog_assign_tail_lsn_locked(struct xfs_mount *mp);
141 void	xfs_log_space_wake(struct xfs_mount *mp);
142 int	xfs_log_reserve(struct xfs_mount *mp, int length, int count,
143 			struct xlog_ticket **ticket, bool permanent);
144 int	xfs_log_regrant(struct xfs_mount *mp, struct xlog_ticket *tic);
145 void	xfs_log_unmount(struct xfs_mount *mp);
146 bool	xfs_log_writable(struct xfs_mount *mp);
147 
148 struct xlog_ticket *xfs_log_ticket_get(struct xlog_ticket *ticket);
149 void	  xfs_log_ticket_put(struct xlog_ticket *ticket);
150 
151 void	xlog_cil_process_committed(struct list_head *list);
152 bool	xfs_log_item_in_current_chkpt(struct xfs_log_item *lip);
153 
154 void	xfs_log_work_queue(struct xfs_mount *mp);
155 int	xfs_log_quiesce(struct xfs_mount *mp);
156 void	xfs_log_clean(struct xfs_mount *mp);
157 bool	xfs_log_check_lsn(struct xfs_mount *, xfs_lsn_t);
158 
159 bool	  xlog_force_shutdown(struct xlog *log, uint32_t shutdown_flags);
160 
161 #endif	/* __XFS_LOG_H__ */
162