1 /*
2  * Copyright (c) 2000-2002,2005 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_ALLOC_H__
19 #define	__XFS_ALLOC_H__
20 
21 struct xfs_buf;
22 struct xfs_mount;
23 struct xfs_perag;
24 struct xfs_trans;
25 
26 /*
27  * Freespace allocation types.  Argument to xfs_alloc_[v]extent.
28  */
29 typedef enum xfs_alloctype
30 {
31 	XFS_ALLOCTYPE_ANY_AG,		/* allocate anywhere, use rotor */
32 	XFS_ALLOCTYPE_FIRST_AG,		/* ... start at ag 0 */
33 	XFS_ALLOCTYPE_START_AG,		/* anywhere, start in this a.g. */
34 	XFS_ALLOCTYPE_THIS_AG,		/* anywhere in this a.g. */
35 	XFS_ALLOCTYPE_START_BNO,	/* near this block else anywhere */
36 	XFS_ALLOCTYPE_NEAR_BNO,		/* in this a.g. and near this block */
37 	XFS_ALLOCTYPE_THIS_BNO		/* at exactly this block */
38 } xfs_alloctype_t;
39 
40 /*
41  * Flags for xfs_alloc_fix_freelist.
42  */
43 #define	XFS_ALLOC_FLAG_TRYLOCK	0x00000001  /* use trylock for buffer locking */
44 
45 /*
46  * Argument structure for xfs_alloc routines.
47  * This is turned into a structure to avoid having 20 arguments passed
48  * down several levels of the stack.
49  */
50 typedef struct xfs_alloc_arg {
51 	struct xfs_trans *tp;		/* transaction pointer */
52 	struct xfs_mount *mp;		/* file system mount point */
53 	struct xfs_buf	*agbp;		/* buffer for a.g. freelist header */
54 	struct xfs_perag *pag;		/* per-ag struct for this agno */
55 	xfs_fsblock_t	fsbno;		/* file system block number */
56 	xfs_agnumber_t	agno;		/* allocation group number */
57 	xfs_agblock_t	agbno;		/* allocation group-relative block # */
58 	xfs_extlen_t	minlen;		/* minimum size of extent */
59 	xfs_extlen_t	maxlen;		/* maximum size of extent */
60 	xfs_extlen_t	mod;		/* mod value for extent size */
61 	xfs_extlen_t	prod;		/* prod value for extent size */
62 	xfs_extlen_t	minleft;	/* min blocks must be left after us */
63 	xfs_extlen_t	total;		/* total blocks needed in xaction */
64 	xfs_extlen_t	alignment;	/* align answer to multiple of this */
65 	xfs_extlen_t	minalignslop;	/* slop for minlen+alignment calcs */
66 	xfs_extlen_t	len;		/* output: actual size of extent */
67 	xfs_alloctype_t	type;		/* allocation type XFS_ALLOCTYPE_... */
68 	xfs_alloctype_t	otype;		/* original allocation type */
69 	char		wasdel;		/* set if allocation was prev delayed */
70 	char		wasfromfl;	/* set if allocation is from freelist */
71 	char		isfl;		/* set if is freelist blocks - !acctg */
72 	char		userdata;	/* set if this is user data */
73 } xfs_alloc_arg_t;
74 
75 /*
76  * Defines for userdata
77  */
78 #define XFS_ALLOC_USERDATA		1	/* allocation is for user data*/
79 #define XFS_ALLOC_INITIAL_USER_DATA	2	/* special case start of file */
80 
81 
82 #ifdef __KERNEL__
83 
84 #if defined(XFS_ALLOC_TRACE)
85 /*
86  * Allocation tracing buffer size.
87  */
88 #define	XFS_ALLOC_TRACE_SIZE	4096
89 extern ktrace_t *xfs_alloc_trace_buf;
90 
91 /*
92  * Types for alloc tracing.
93  */
94 #define	XFS_ALLOC_KTRACE_ALLOC	1
95 #define	XFS_ALLOC_KTRACE_FREE	2
96 #define	XFS_ALLOC_KTRACE_MODAGF	3
97 #define	XFS_ALLOC_KTRACE_BUSY	4
98 #define	XFS_ALLOC_KTRACE_UNBUSY	5
99 #define	XFS_ALLOC_KTRACE_BUSYSEARCH	6
100 #endif
101 
102 /*
103  * Compute and fill in value of m_ag_maxlevels.
104  */
105 void
106 xfs_alloc_compute_maxlevels(
107 	struct xfs_mount	*mp);	/* file system mount structure */
108 
109 /*
110  * Get a block from the freelist.
111  * Returns with the buffer for the block gotten.
112  */
113 int				/* error */
114 xfs_alloc_get_freelist(
115 	struct xfs_trans *tp,	/* transaction pointer */
116 	struct xfs_buf	*agbp,	/* buffer containing the agf structure */
117 	xfs_agblock_t	*bnop);	/* block address retrieved from freelist */
118 
119 /*
120  * Log the given fields from the agf structure.
121  */
122 void
123 xfs_alloc_log_agf(
124 	struct xfs_trans *tp,	/* transaction pointer */
125 	struct xfs_buf	*bp,	/* buffer for a.g. freelist header */
126 	int		fields);/* mask of fields to be logged (XFS_AGF_...) */
127 
128 /*
129  * Interface for inode allocation to force the pag data to be initialized.
130  */
131 int				/* error */
132 xfs_alloc_pagf_init(
133 	struct xfs_mount *mp,	/* file system mount structure */
134 	struct xfs_trans *tp,	/* transaction pointer */
135 	xfs_agnumber_t	agno,	/* allocation group number */
136 	int		flags);	/* XFS_ALLOC_FLAGS_... */
137 
138 /*
139  * Put the block on the freelist for the allocation group.
140  */
141 int				/* error */
142 xfs_alloc_put_freelist(
143 	struct xfs_trans *tp,	/* transaction pointer */
144 	struct xfs_buf	*agbp,	/* buffer for a.g. freelist header */
145 	struct xfs_buf	*agflbp,/* buffer for a.g. free block array */
146 	xfs_agblock_t	bno);	/* block being freed */
147 
148 /*
149  * Read in the allocation group header (free/alloc section).
150  */
151 int					/* error  */
152 xfs_alloc_read_agf(
153 	struct xfs_mount *mp,		/* mount point structure */
154 	struct xfs_trans *tp,		/* transaction pointer */
155 	xfs_agnumber_t	agno,		/* allocation group number */
156 	int		flags,		/* XFS_ALLOC_FLAG_... */
157 	struct xfs_buf	**bpp);		/* buffer for the ag freelist header */
158 
159 /*
160  * Allocate an extent (variable-size).
161  */
162 int				/* error */
163 xfs_alloc_vextent(
164 	xfs_alloc_arg_t	*args);	/* allocation argument structure */
165 
166 /*
167  * Free an extent.
168  */
169 int				/* error */
170 xfs_free_extent(
171 	struct xfs_trans *tp,	/* transaction pointer */
172 	xfs_fsblock_t	bno,	/* starting block number of extent */
173 	xfs_extlen_t	len);	/* length of extent */
174 
175 void
176 xfs_alloc_mark_busy(xfs_trans_t *tp,
177 		xfs_agnumber_t agno,
178 		xfs_agblock_t bno,
179 		xfs_extlen_t len);
180 
181 void
182 xfs_alloc_clear_busy(xfs_trans_t *tp,
183 		xfs_agnumber_t ag,
184 		int idx);
185 
186 
187 #endif	/* __KERNEL__ */
188 
189 #endif	/* __XFS_ALLOC_H__ */
190