1 /*
2  * Copyright (c) 2000-2002 Silicon Graphics, Inc.  All Rights Reserved.
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms of version 2 of the GNU General Public License as
6  * published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it would be useful, but
9  * WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
11  *
12  * Further, this software is distributed without any warranty that it is
13  * free of the rightful claim of any third person regarding infringement
14  * or the like.  Any license provided herein, whether implied or
15  * otherwise, applies only to this software file.  Patent licenses, if
16  * any, provided herein do not apply to combinations of this program with
17  * other software, or any other product whatsoever.
18  *
19  * You should have received a copy of the GNU General Public License along
20  * with this program; if not, write the Free Software Foundation, Inc., 59
21  * Temple Place - Suite 330, Boston MA 02111-1307, USA.
22  *
23  * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
24  * Mountain View, CA  94043, or:
25  *
26  * http://www.sgi.com
27  *
28  * For further information regarding this notice, see:
29  *
30  * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
31  */
32 #ifndef __XFS_ALLOC_H__
33 #define	__XFS_ALLOC_H__
34 
35 struct xfs_buf;
36 struct xfs_mount;
37 struct xfs_perag;
38 struct xfs_trans;
39 
40 /*
41  * Freespace allocation types.  Argument to xfs_alloc_[v]extent.
42  */
43 typedef enum xfs_alloctype
44 {
45 	XFS_ALLOCTYPE_ANY_AG,		/* allocate anywhere, use rotor */
46 	XFS_ALLOCTYPE_FIRST_AG,		/* ... start at ag 0 */
47 	XFS_ALLOCTYPE_START_AG,		/* anywhere, start in this a.g. */
48 	XFS_ALLOCTYPE_THIS_AG,		/* anywhere in this a.g. */
49 	XFS_ALLOCTYPE_START_BNO,	/* near this block else anywhere */
50 	XFS_ALLOCTYPE_NEAR_BNO,		/* in this a.g. and near this block */
51 	XFS_ALLOCTYPE_THIS_BNO		/* at exactly this block */
52 } xfs_alloctype_t;
53 
54 /*
55  * Flags for xfs_alloc_fix_freelist.
56  */
57 #define	XFS_ALLOC_FLAG_TRYLOCK	0x00000001  /* use trylock for buffer locking */
58 
59 /*
60  * Argument structure for xfs_alloc routines.
61  * This is turned into a structure to avoid having 20 arguments passed
62  * down several levels of the stack.
63  */
64 typedef struct xfs_alloc_arg {
65 	struct xfs_trans *tp;		/* transaction pointer */
66 	struct xfs_mount *mp;		/* file system mount point */
67 	struct xfs_buf	*agbp;		/* buffer for a.g. freelist header */
68 	struct xfs_perag *pag;		/* per-ag struct for this agno */
69 	xfs_fsblock_t	fsbno;		/* file system block number */
70 	xfs_agnumber_t	agno;		/* allocation group number */
71 	xfs_agblock_t	agbno;		/* allocation group-relative block # */
72 	xfs_extlen_t	minlen;		/* minimum size of extent */
73 	xfs_extlen_t	maxlen;		/* maximum size of extent */
74 	xfs_extlen_t	mod;		/* mod value for extent size */
75 	xfs_extlen_t	prod;		/* prod value for extent size */
76 	xfs_extlen_t	minleft;	/* min blocks must be left after us */
77 	xfs_extlen_t	total;		/* total blocks needed in xaction */
78 	xfs_extlen_t	alignment;	/* align answer to multiple of this */
79 	xfs_extlen_t	minalignslop;	/* slop for minlen+alignment calcs */
80 	xfs_extlen_t	len;		/* output: actual size of extent */
81 	xfs_alloctype_t	type;		/* allocation type XFS_ALLOCTYPE_... */
82 	xfs_alloctype_t	otype;		/* original allocation type */
83 	char		wasdel;		/* set if allocation was prev delayed */
84 	char		wasfromfl;	/* set if allocation is from freelist */
85 	char		isfl;		/* set if is freelist blocks - !actg */
86 	char		userdata;	/* set if this is user data */
87 } xfs_alloc_arg_t;
88 
89 /*
90  * Defines for userdata
91  */
92 #define XFS_ALLOC_USERDATA		1	/* allocation is for user data*/
93 #define XFS_ALLOC_INITIAL_USER_DATA	2	/* special case start of file */
94 
95 
96 #ifdef __KERNEL__
97 
98 #if defined(XFS_ALLOC_TRACE)
99 /*
100  * Allocation tracing buffer size.
101  */
102 #define	XFS_ALLOC_TRACE_SIZE	4096
103 extern ktrace_t *xfs_alloc_trace_buf;
104 
105 /*
106  * Types for alloc tracing.
107  */
108 #define	XFS_ALLOC_KTRACE_ALLOC	1
109 #define	XFS_ALLOC_KTRACE_FREE	2
110 #define	XFS_ALLOC_KTRACE_MODAGF	3
111 #define	XFS_ALLOC_KTRACE_BUSY	4
112 #define	XFS_ALLOC_KTRACE_UNBUSY	5
113 #define	XFS_ALLOC_KTRACE_BUSYSEARCH	6
114 #endif
115 
116 /*
117  * Compute and fill in value of m_ag_maxlevels.
118  */
119 void
120 xfs_alloc_compute_maxlevels(
121 	struct xfs_mount	*mp);	/* file system mount structure */
122 
123 /*
124  * Get a block from the freelist.
125  * Returns with the buffer for the block gotten.
126  */
127 int				/* error */
128 xfs_alloc_get_freelist(
129 	struct xfs_trans *tp,	/* transaction pointer */
130 	struct xfs_buf	*agbp,	/* buffer containing the agf structure */
131 	xfs_agblock_t	*bnop);	/* block address retrieved from freelist */
132 
133 /*
134  * Log the given fields from the agf structure.
135  */
136 void
137 xfs_alloc_log_agf(
138 	struct xfs_trans *tp,	/* transaction pointer */
139 	struct xfs_buf	*bp,	/* buffer for a.g. freelist header */
140 	int		fields);/* mask of fields to be logged (XFS_AGF_...) */
141 
142 /*
143  * Interface for inode allocation to force the pag data to be initialized.
144  */
145 int				/* error */
146 xfs_alloc_pagf_init(
147 	struct xfs_mount *mp,	/* file system mount structure */
148 	struct xfs_trans *tp,	/* transaction pointer */
149 	xfs_agnumber_t	agno,	/* allocation group number */
150 	int		flags);	/* XFS_ALLOC_FLAGS_... */
151 
152 /*
153  * Put the block on the freelist for the allocation group.
154  */
155 int				/* error */
156 xfs_alloc_put_freelist(
157 	struct xfs_trans *tp,	/* transaction pointer */
158 	struct xfs_buf	*agbp,	/* buffer for a.g. freelist header */
159 	struct xfs_buf	*agflbp,/* buffer for a.g. free block array */
160 	xfs_agblock_t	bno);	/* block being freed */
161 
162 /*
163  * Read in the allocation group header (free/alloc section).
164  */
165 int					/* error  */
166 xfs_alloc_read_agf(
167 	struct xfs_mount *mp,		/* mount point structure */
168 	struct xfs_trans *tp,		/* transaction pointer */
169 	xfs_agnumber_t	agno,		/* allocation group number */
170 	int		flags,		/* XFS_ALLOC_FLAG_... */
171 	struct xfs_buf	**bpp);		/* buffer for the ag freelist header */
172 
173 /*
174  * Allocate an extent (variable-size).
175  */
176 int				/* error */
177 xfs_alloc_vextent(
178 	xfs_alloc_arg_t	*args);	/* allocation argument structure */
179 
180 /*
181  * Free an extent.
182  */
183 int				/* error */
184 xfs_free_extent(
185 	struct xfs_trans *tp,	/* transaction pointer */
186 	xfs_fsblock_t	bno,	/* starting block number of extent */
187 	xfs_extlen_t	len);	/* length of extent */
188 
189 void
190 xfs_alloc_mark_busy(xfs_trans_t *tp,
191 		xfs_agnumber_t agno,
192 		xfs_agblock_t bno,
193 		xfs_extlen_t len);
194 
195 void
196 xfs_alloc_clear_busy(xfs_trans_t *tp,
197 		xfs_agnumber_t ag,
198 		int idx);
199 
200 
201 #endif	/* __KERNEL__ */
202 
203 #endif	/* __XFS_ALLOC_H__ */
204