xref: /linux/fs/xfs/xfs_log.h (revision f3f5edc5e41e038cf66d124a4cbacf6ff0983513)
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_used;	/* buffer space used so far */
20 	int			lv_alloc_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
xlog_calc_iovec_len(int len)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
xlog_finish_iovec(struct xfs_log_vec * lv,struct xfs_log_iovec * vec,int data_len)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_used += 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 <=
73 		(void *)lv + lv->lv_alloc_size);
74 }
75 
76 /*
77  * Copy the amount of data requested by the caller into a new log iovec.
78  */
79 static inline void *
xlog_copy_iovec(struct xfs_log_vec * lv,struct xfs_log_iovec ** vecp,uint type,void * data,int len)80 xlog_copy_iovec(struct xfs_log_vec *lv, struct xfs_log_iovec **vecp,
81 		uint type, void *data, int len)
82 {
83 	void *buf;
84 
85 	buf = xlog_prepare_iovec(lv, vecp, type);
86 	memcpy(buf, data, len);
87 	xlog_finish_iovec(lv, *vecp, len);
88 	return buf;
89 }
90 
91 /*
92  * By comparing each component, we don't have to worry about extra
93  * endian issues in treating two 32 bit numbers as one 64 bit number
94  */
_lsn_cmp(xfs_lsn_t lsn1,xfs_lsn_t lsn2)95 static inline xfs_lsn_t	_lsn_cmp(xfs_lsn_t lsn1, xfs_lsn_t lsn2)
96 {
97 	if (CYCLE_LSN(lsn1) != CYCLE_LSN(lsn2))
98 		return (CYCLE_LSN(lsn1)<CYCLE_LSN(lsn2))? -999 : 999;
99 
100 	if (BLOCK_LSN(lsn1) != BLOCK_LSN(lsn2))
101 		return (BLOCK_LSN(lsn1)<BLOCK_LSN(lsn2))? -999 : 999;
102 
103 	return 0;
104 }
105 
106 #define	XFS_LSN_CMP(x,y) _lsn_cmp(x,y)
107 
108 /*
109  * Flags to xfs_log_force()
110  *
111  *	XFS_LOG_SYNC:	Synchronous force in-core log to disk
112  */
113 #define XFS_LOG_SYNC		0x1
114 
115 /* Log manager interfaces */
116 struct xfs_mount;
117 struct xlog_in_core;
118 struct xlog_ticket;
119 struct xfs_log_item;
120 struct xfs_item_ops;
121 struct xfs_trans;
122 struct xlog;
123 
124 int	  xfs_log_force(struct xfs_mount *mp, uint flags);
125 int	  xfs_log_force_seq(struct xfs_mount *mp, xfs_csn_t seq, uint flags,
126 		int *log_forced);
127 int	  xfs_log_mount(struct xfs_mount	*mp,
128 			struct xfs_buftarg	*log_target,
129 			xfs_daddr_t		start_block,
130 			int		 	num_bblocks);
131 int	  xfs_log_mount_finish(struct xfs_mount *mp);
132 void	xfs_log_mount_cancel(struct xfs_mount *);
133 xfs_lsn_t xlog_assign_tail_lsn(struct xfs_mount *mp);
134 xfs_lsn_t xlog_assign_tail_lsn_locked(struct xfs_mount *mp);
135 void	xfs_log_space_wake(struct xfs_mount *mp);
136 int	xfs_log_reserve(struct xfs_mount *mp, int length, int count,
137 			struct xlog_ticket **ticket, bool permanent);
138 int	xfs_log_regrant(struct xfs_mount *mp, struct xlog_ticket *tic);
139 void	xfs_log_unmount(struct xfs_mount *mp);
140 bool	xfs_log_writable(struct xfs_mount *mp);
141 
142 struct xlog_ticket *xfs_log_ticket_get(struct xlog_ticket *ticket);
143 void	  xfs_log_ticket_put(struct xlog_ticket *ticket);
144 
145 void	xlog_cil_process_committed(struct list_head *list);
146 bool	xfs_log_item_in_current_chkpt(struct xfs_log_item *lip);
147 
148 void	xfs_log_work_queue(struct xfs_mount *mp);
149 int	xfs_log_quiesce(struct xfs_mount *mp);
150 void	xfs_log_clean(struct xfs_mount *mp);
151 bool	xfs_log_check_lsn(struct xfs_mount *, xfs_lsn_t);
152 
153 bool	  xlog_force_shutdown(struct xlog *log, uint32_t shutdown_flags);
154 
155 #endif	/* __XFS_LOG_H__ */
156