xref: /linux/fs/xfs/xfs_buf_item.h (revision ee1a47ab0e77600fcbdf1c87d461bd8f3f63150d)
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 
49 #define XFS_BLF_TYPE_MASK	\
50 		(XFS_BLF_UDQUOT_BUF | \
51 		 XFS_BLF_PDQUOT_BUF | \
52 		 XFS_BLF_GDQUOT_BUF | \
53 		 XFS_BLF_BTREE_BUF)
54 
55 #define	XFS_BLF_CHUNK		128
56 #define	XFS_BLF_SHIFT		7
57 #define	BIT_TO_WORD_SHIFT	5
58 #define	NBWORD			(NBBY * sizeof(unsigned int))
59 
60 /*
61  * This is the structure used to lay out a buf log item in the
62  * log.  The data map describes which 128 byte chunks of the buffer
63  * have been logged.
64  */
65 #define XFS_BLF_DATAMAP_SIZE	((XFS_MAX_BLOCKSIZE / XFS_BLF_CHUNK) / NBWORD)
66 
67 typedef struct xfs_buf_log_format {
68 	unsigned short	blf_type;	/* buf log item type indicator */
69 	unsigned short	blf_size;	/* size of this item */
70 	ushort		blf_flags;	/* misc state */
71 	ushort		blf_len;	/* number of blocks in this buf */
72 	__int64_t	blf_blkno;	/* starting blkno of this buf */
73 	unsigned int	blf_map_size;	/* used size of data bitmap in words */
74 	unsigned int	blf_data_map[XFS_BLF_DATAMAP_SIZE]; /* dirty bitmap */
75 } xfs_buf_log_format_t;
76 
77 /*
78  * buf log item flags
79  */
80 #define	XFS_BLI_HOLD		0x01
81 #define	XFS_BLI_DIRTY		0x02
82 #define	XFS_BLI_STALE		0x04
83 #define	XFS_BLI_LOGGED		0x08
84 #define	XFS_BLI_INODE_ALLOC_BUF	0x10
85 #define XFS_BLI_STALE_INODE	0x20
86 #define	XFS_BLI_INODE_BUF	0x40
87 
88 #define XFS_BLI_FLAGS \
89 	{ XFS_BLI_HOLD,		"HOLD" }, \
90 	{ XFS_BLI_DIRTY,	"DIRTY" }, \
91 	{ XFS_BLI_STALE,	"STALE" }, \
92 	{ XFS_BLI_LOGGED,	"LOGGED" }, \
93 	{ XFS_BLI_INODE_ALLOC_BUF, "INODE_ALLOC" }, \
94 	{ XFS_BLI_STALE_INODE,	"STALE_INODE" }, \
95 	{ XFS_BLI_INODE_BUF,	"INODE_BUF" }
96 
97 
98 #ifdef __KERNEL__
99 
100 struct xfs_buf;
101 struct xfs_mount;
102 struct xfs_buf_log_item;
103 
104 /*
105  * This is the in core log item structure used to track information
106  * needed to log buffers.  It tracks how many times the lock has been
107  * locked, and which 128 byte chunks of the buffer are dirty.
108  */
109 typedef struct xfs_buf_log_item {
110 	xfs_log_item_t		bli_item;	/* common item structure */
111 	struct xfs_buf		*bli_buf;	/* real buffer pointer */
112 	unsigned int		bli_flags;	/* misc flags */
113 	unsigned int		bli_recur;	/* lock recursion count */
114 	atomic_t		bli_refcount;	/* cnt of tp refs */
115 	int			bli_format_count;	/* count of headers */
116 	struct xfs_buf_log_format *bli_formats;	/* array of in-log header ptrs */
117 	struct xfs_buf_log_format __bli_format;	/* embedded in-log header */
118 } xfs_buf_log_item_t;
119 
120 void	xfs_buf_item_init(struct xfs_buf *, struct xfs_mount *);
121 void	xfs_buf_item_relse(struct xfs_buf *);
122 void	xfs_buf_item_log(xfs_buf_log_item_t *, uint, uint);
123 uint	xfs_buf_item_dirty(xfs_buf_log_item_t *);
124 void	xfs_buf_attach_iodone(struct xfs_buf *,
125 			      void(*)(struct xfs_buf *, xfs_log_item_t *),
126 			      xfs_log_item_t *);
127 void	xfs_buf_iodone_callbacks(struct xfs_buf *);
128 void	xfs_buf_iodone(struct xfs_buf *, struct xfs_log_item *);
129 
130 #endif	/* __KERNEL__ */
131 
132 #endif	/* __XFS_BUF_ITEM_H__ */
133