xref: /linux/fs/xfs/xfs_buf_item.h (revision 93848a999cf9b9e4f4f77dba843a48c393f33c59)
1 /*
2  * Copyright (c) 2000-2001,2005 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_BUF_ITEM_H__
19 #define	__XFS_BUF_ITEM_H__
20 
21 extern kmem_zone_t	*xfs_buf_item_zone;
22 
23 /*
24  * This flag indicates that the buffer contains on disk inodes
25  * and requires special recovery handling.
26  */
27 #define	XFS_BLF_INODE_BUF	(1<<0)
28 /*
29  * This flag indicates that the buffer should not be replayed
30  * during recovery because its blocks are being freed.
31  */
32 #define	XFS_BLF_CANCEL		(1<<1)
33 
34 /*
35  * This flag indicates that the buffer contains on disk
36  * user or group dquots and may require special recovery handling.
37  */
38 #define	XFS_BLF_UDQUOT_BUF	(1<<2)
39 #define XFS_BLF_PDQUOT_BUF	(1<<3)
40 #define	XFS_BLF_GDQUOT_BUF	(1<<4)
41 
42 /*
43  * all buffers now need flags to tell recovery where the magic number
44  * is so that it can verify and calculate the CRCs on the buffer correctly
45  * once the changes have been replayed into the buffer.
46  */
47 #define XFS_BLF_BTREE_BUF	(1<<5)
48 #define XFS_BLF_AGF_BUF		(1<<6)
49 #define XFS_BLF_AGFL_BUF	(1<<7)
50 #define XFS_BLF_AGI_BUF		(1<<8)
51 #define XFS_BLF_DINO_BUF	(1<<9)
52 
53 #define XFS_BLF_TYPE_MASK	\
54 		(XFS_BLF_UDQUOT_BUF | \
55 		 XFS_BLF_PDQUOT_BUF | \
56 		 XFS_BLF_GDQUOT_BUF | \
57 		 XFS_BLF_BTREE_BUF | \
58 		 XFS_BLF_AGF_BUF | \
59 		 XFS_BLF_AGFL_BUF | \
60 		 XFS_BLF_AGI_BUF | \
61 		 XFS_BLF_DINO_BUF)
62 
63 #define	XFS_BLF_CHUNK		128
64 #define	XFS_BLF_SHIFT		7
65 #define	BIT_TO_WORD_SHIFT	5
66 #define	NBWORD			(NBBY * sizeof(unsigned int))
67 
68 /*
69  * This is the structure used to lay out a buf log item in the
70  * log.  The data map describes which 128 byte chunks of the buffer
71  * have been logged.
72  */
73 #define XFS_BLF_DATAMAP_SIZE	((XFS_MAX_BLOCKSIZE / XFS_BLF_CHUNK) / NBWORD)
74 
75 typedef struct xfs_buf_log_format {
76 	unsigned short	blf_type;	/* buf log item type indicator */
77 	unsigned short	blf_size;	/* size of this item */
78 	ushort		blf_flags;	/* misc state */
79 	ushort		blf_len;	/* number of blocks in this buf */
80 	__int64_t	blf_blkno;	/* starting blkno of this buf */
81 	unsigned int	blf_map_size;	/* used size of data bitmap in words */
82 	unsigned int	blf_data_map[XFS_BLF_DATAMAP_SIZE]; /* dirty bitmap */
83 } xfs_buf_log_format_t;
84 
85 /*
86  * buf log item flags
87  */
88 #define	XFS_BLI_HOLD		0x01
89 #define	XFS_BLI_DIRTY		0x02
90 #define	XFS_BLI_STALE		0x04
91 #define	XFS_BLI_LOGGED		0x08
92 #define	XFS_BLI_INODE_ALLOC_BUF	0x10
93 #define XFS_BLI_STALE_INODE	0x20
94 #define	XFS_BLI_INODE_BUF	0x40
95 
96 #define XFS_BLI_FLAGS \
97 	{ XFS_BLI_HOLD,		"HOLD" }, \
98 	{ XFS_BLI_DIRTY,	"DIRTY" }, \
99 	{ XFS_BLI_STALE,	"STALE" }, \
100 	{ XFS_BLI_LOGGED,	"LOGGED" }, \
101 	{ XFS_BLI_INODE_ALLOC_BUF, "INODE_ALLOC" }, \
102 	{ XFS_BLI_STALE_INODE,	"STALE_INODE" }, \
103 	{ XFS_BLI_INODE_BUF,	"INODE_BUF" }
104 
105 
106 #ifdef __KERNEL__
107 
108 struct xfs_buf;
109 struct xfs_mount;
110 struct xfs_buf_log_item;
111 
112 /*
113  * This is the in core log item structure used to track information
114  * needed to log buffers.  It tracks how many times the lock has been
115  * locked, and which 128 byte chunks of the buffer are dirty.
116  */
117 typedef struct xfs_buf_log_item {
118 	xfs_log_item_t		bli_item;	/* common item structure */
119 	struct xfs_buf		*bli_buf;	/* real buffer pointer */
120 	unsigned int		bli_flags;	/* misc flags */
121 	unsigned int		bli_recur;	/* lock recursion count */
122 	atomic_t		bli_refcount;	/* cnt of tp refs */
123 	int			bli_format_count;	/* count of headers */
124 	struct xfs_buf_log_format *bli_formats;	/* array of in-log header ptrs */
125 	struct xfs_buf_log_format __bli_format;	/* embedded in-log header */
126 } xfs_buf_log_item_t;
127 
128 void	xfs_buf_item_init(struct xfs_buf *, struct xfs_mount *);
129 void	xfs_buf_item_relse(struct xfs_buf *);
130 void	xfs_buf_item_log(xfs_buf_log_item_t *, uint, uint);
131 uint	xfs_buf_item_dirty(xfs_buf_log_item_t *);
132 void	xfs_buf_attach_iodone(struct xfs_buf *,
133 			      void(*)(struct xfs_buf *, xfs_log_item_t *),
134 			      xfs_log_item_t *);
135 void	xfs_buf_iodone_callbacks(struct xfs_buf *);
136 void	xfs_buf_iodone(struct xfs_buf *, struct xfs_log_item *);
137 
138 #endif	/* __KERNEL__ */
139 
140 #endif	/* __XFS_BUF_ITEM_H__ */
141