xref: /openbmc/linux/fs/xfs/libxfs/xfs_alloc.h (revision 4f6cce39)
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_btree_cur;
23 struct xfs_mount;
24 struct xfs_perag;
25 struct xfs_trans;
26 
27 extern struct workqueue_struct *xfs_alloc_wq;
28 
29 /*
30  * Freespace allocation types.  Argument to xfs_alloc_[v]extent.
31  */
32 #define XFS_ALLOCTYPE_FIRST_AG	0x02	/* ... start at ag 0 */
33 #define XFS_ALLOCTYPE_THIS_AG	0x08	/* anywhere in this a.g. */
34 #define XFS_ALLOCTYPE_START_BNO	0x10	/* near this block else anywhere */
35 #define XFS_ALLOCTYPE_NEAR_BNO	0x20	/* in this a.g. and near this block */
36 #define XFS_ALLOCTYPE_THIS_BNO	0x40	/* at exactly this block */
37 
38 /* this should become an enum again when the tracing code is fixed */
39 typedef unsigned int xfs_alloctype_t;
40 
41 #define XFS_ALLOC_TYPES \
42 	{ XFS_ALLOCTYPE_FIRST_AG,	"FIRST_AG" }, \
43 	{ XFS_ALLOCTYPE_THIS_AG,	"THIS_AG" }, \
44 	{ XFS_ALLOCTYPE_START_BNO,	"START_BNO" }, \
45 	{ XFS_ALLOCTYPE_NEAR_BNO,	"NEAR_BNO" }, \
46 	{ XFS_ALLOCTYPE_THIS_BNO,	"THIS_BNO" }
47 
48 /*
49  * Flags for xfs_alloc_fix_freelist.
50  */
51 #define	XFS_ALLOC_FLAG_TRYLOCK	0x00000001  /* use trylock for buffer locking */
52 #define	XFS_ALLOC_FLAG_FREEING	0x00000002  /* indicate caller is freeing extents*/
53 #define	XFS_ALLOC_FLAG_NORMAP	0x00000004  /* don't modify the rmapbt */
54 #define	XFS_ALLOC_FLAG_NOSHRINK	0x00000008  /* don't shrink the freelist */
55 #define	XFS_ALLOC_FLAG_CHECK	0x00000010  /* test only, don't modify args */
56 
57 /*
58  * Argument structure for xfs_alloc routines.
59  * This is turned into a structure to avoid having 20 arguments passed
60  * down several levels of the stack.
61  */
62 typedef struct xfs_alloc_arg {
63 	struct xfs_trans *tp;		/* transaction pointer */
64 	struct xfs_mount *mp;		/* file system mount point */
65 	struct xfs_buf	*agbp;		/* buffer for a.g. freelist header */
66 	struct xfs_perag *pag;		/* per-ag struct for this agno */
67 	struct xfs_inode *ip;		/* for userdata zeroing method */
68 	xfs_fsblock_t	fsbno;		/* file system block number */
69 	xfs_agnumber_t	agno;		/* allocation group number */
70 	xfs_agblock_t	agbno;		/* allocation group-relative block # */
71 	xfs_extlen_t	minlen;		/* minimum size of extent */
72 	xfs_extlen_t	maxlen;		/* maximum size of extent */
73 	xfs_extlen_t	mod;		/* mod value for extent size */
74 	xfs_extlen_t	prod;		/* prod value for extent size */
75 	xfs_extlen_t	minleft;	/* min blocks must be left after us */
76 	xfs_extlen_t	total;		/* total blocks needed in xaction */
77 	xfs_extlen_t	alignment;	/* align answer to multiple of this */
78 	xfs_extlen_t	minalignslop;	/* slop for minlen+alignment calcs */
79 	xfs_agblock_t	min_agbno;	/* set an agbno range for NEAR allocs */
80 	xfs_agblock_t	max_agbno;	/* ... */
81 	xfs_extlen_t	len;		/* output: actual size of extent */
82 	xfs_alloctype_t	type;		/* allocation type XFS_ALLOCTYPE_... */
83 	xfs_alloctype_t	otype;		/* original allocation type */
84 	int		datatype;	/* mask defining data type treatment */
85 	char		wasdel;		/* set if allocation was prev delayed */
86 	char		wasfromfl;	/* set if allocation is from freelist */
87 	xfs_fsblock_t	firstblock;	/* io first block allocated */
88 	struct xfs_owner_info	oinfo;	/* owner of blocks being allocated */
89 	enum xfs_ag_resv_type	resv;	/* block reservation to use */
90 } xfs_alloc_arg_t;
91 
92 /*
93  * Defines for datatype
94  */
95 #define XFS_ALLOC_USERDATA		(1 << 0)/* allocation is for user data*/
96 #define XFS_ALLOC_INITIAL_USER_DATA	(1 << 1)/* special case start of file */
97 #define XFS_ALLOC_USERDATA_ZERO		(1 << 2)/* zero extent on allocation */
98 #define XFS_ALLOC_NOBUSY		(1 << 3)/* Busy extents not allowed */
99 
100 static inline bool
101 xfs_alloc_is_userdata(int datatype)
102 {
103 	return (datatype & ~XFS_ALLOC_NOBUSY) != 0;
104 }
105 
106 static inline bool
107 xfs_alloc_allow_busy_reuse(int datatype)
108 {
109 	return (datatype & XFS_ALLOC_NOBUSY) == 0;
110 }
111 
112 /* freespace limit calculations */
113 #define XFS_ALLOC_AGFL_RESERVE	4
114 unsigned int xfs_alloc_set_aside(struct xfs_mount *mp);
115 unsigned int xfs_alloc_ag_max_usable(struct xfs_mount *mp);
116 
117 xfs_extlen_t xfs_alloc_longest_free_extent(struct xfs_mount *mp,
118 		struct xfs_perag *pag, xfs_extlen_t need,
119 		xfs_extlen_t reserved);
120 unsigned int xfs_alloc_min_freelist(struct xfs_mount *mp,
121 		struct xfs_perag *pag);
122 
123 /*
124  * Compute and fill in value of m_ag_maxlevels.
125  */
126 void
127 xfs_alloc_compute_maxlevels(
128 	struct xfs_mount	*mp);	/* file system mount structure */
129 
130 /*
131  * Get a block from the freelist.
132  * Returns with the buffer for the block gotten.
133  */
134 int				/* error */
135 xfs_alloc_get_freelist(
136 	struct xfs_trans *tp,	/* transaction pointer */
137 	struct xfs_buf	*agbp,	/* buffer containing the agf structure */
138 	xfs_agblock_t	*bnop,	/* block address retrieved from freelist */
139 	int		btreeblk); /* destination is a AGF btree */
140 
141 /*
142  * Log the given fields from the agf structure.
143  */
144 void
145 xfs_alloc_log_agf(
146 	struct xfs_trans *tp,	/* transaction pointer */
147 	struct xfs_buf	*bp,	/* buffer for a.g. freelist header */
148 	int		fields);/* mask of fields to be logged (XFS_AGF_...) */
149 
150 /*
151  * Interface for inode allocation to force the pag data to be initialized.
152  */
153 int				/* error */
154 xfs_alloc_pagf_init(
155 	struct xfs_mount *mp,	/* file system mount structure */
156 	struct xfs_trans *tp,	/* transaction pointer */
157 	xfs_agnumber_t	agno,	/* allocation group number */
158 	int		flags);	/* XFS_ALLOC_FLAGS_... */
159 
160 /*
161  * Put the block on the freelist for the allocation group.
162  */
163 int				/* error */
164 xfs_alloc_put_freelist(
165 	struct xfs_trans *tp,	/* transaction pointer */
166 	struct xfs_buf	*agbp,	/* buffer for a.g. freelist header */
167 	struct xfs_buf	*agflbp,/* buffer for a.g. free block array */
168 	xfs_agblock_t	bno,	/* block being freed */
169 	int		btreeblk); /* owner was a AGF btree */
170 
171 /*
172  * Read in the allocation group header (free/alloc section).
173  */
174 int					/* error  */
175 xfs_alloc_read_agf(
176 	struct xfs_mount *mp,		/* mount point structure */
177 	struct xfs_trans *tp,		/* transaction pointer */
178 	xfs_agnumber_t	agno,		/* allocation group number */
179 	int		flags,		/* XFS_ALLOC_FLAG_... */
180 	struct xfs_buf	**bpp);		/* buffer for the ag freelist header */
181 
182 /*
183  * Allocate an extent (variable-size).
184  */
185 int				/* error */
186 xfs_alloc_vextent(
187 	xfs_alloc_arg_t	*args);	/* allocation argument structure */
188 
189 /*
190  * Free an extent.
191  */
192 int				/* error */
193 xfs_free_extent(
194 	struct xfs_trans	*tp,	/* transaction pointer */
195 	xfs_fsblock_t		bno,	/* starting block number of extent */
196 	xfs_extlen_t		len,	/* length of extent */
197 	struct xfs_owner_info	*oinfo,	/* extent owner */
198 	enum xfs_ag_resv_type	type);	/* block reservation type */
199 
200 int				/* error */
201 xfs_alloc_lookup_ge(
202 	struct xfs_btree_cur	*cur,	/* btree cursor */
203 	xfs_agblock_t		bno,	/* starting block of extent */
204 	xfs_extlen_t		len,	/* length of extent */
205 	int			*stat);	/* success/failure */
206 
207 int					/* error */
208 xfs_alloc_get_rec(
209 	struct xfs_btree_cur	*cur,	/* btree cursor */
210 	xfs_agblock_t		*bno,	/* output: starting block of extent */
211 	xfs_extlen_t		*len,	/* output: length of extent */
212 	int			*stat);	/* output: success/failure */
213 
214 int xfs_read_agf(struct xfs_mount *mp, struct xfs_trans *tp,
215 			xfs_agnumber_t agno, int flags, struct xfs_buf **bpp);
216 int xfs_alloc_fix_freelist(struct xfs_alloc_arg *args, int flags);
217 int xfs_free_extent_fix_freelist(struct xfs_trans *tp, xfs_agnumber_t agno,
218 		struct xfs_buf **agbp);
219 
220 xfs_extlen_t xfs_prealloc_blocks(struct xfs_mount *mp);
221 
222 #endif	/* __XFS_ALLOC_H__ */
223