xref: /openbmc/linux/fs/xfs/libxfs/xfs_alloc.h (revision 82003e04)
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_ANY_AG	0x01	/* allocate anywhere, use rotor */
33 #define XFS_ALLOCTYPE_FIRST_AG	0x02	/* ... start at ag 0 */
34 #define XFS_ALLOCTYPE_START_AG	0x04	/* anywhere, start in this a.g. */
35 #define XFS_ALLOCTYPE_THIS_AG	0x08	/* anywhere in this a.g. */
36 #define XFS_ALLOCTYPE_START_BNO	0x10	/* near this block else anywhere */
37 #define XFS_ALLOCTYPE_NEAR_BNO	0x20	/* in this a.g. and near this block */
38 #define XFS_ALLOCTYPE_THIS_BNO	0x40	/* at exactly this block */
39 
40 /* this should become an enum again when the tracing code is fixed */
41 typedef unsigned int xfs_alloctype_t;
42 
43 #define XFS_ALLOC_TYPES \
44 	{ XFS_ALLOCTYPE_ANY_AG,		"ANY_AG" }, \
45 	{ XFS_ALLOCTYPE_FIRST_AG,	"FIRST_AG" }, \
46 	{ XFS_ALLOCTYPE_START_AG,	"START_AG" }, \
47 	{ XFS_ALLOCTYPE_THIS_AG,	"THIS_AG" }, \
48 	{ XFS_ALLOCTYPE_START_BNO,	"START_BNO" }, \
49 	{ XFS_ALLOCTYPE_NEAR_BNO,	"NEAR_BNO" }, \
50 	{ XFS_ALLOCTYPE_THIS_BNO,	"THIS_BNO" }
51 
52 /*
53  * Flags for xfs_alloc_fix_freelist.
54  */
55 #define	XFS_ALLOC_FLAG_TRYLOCK	0x00000001  /* use trylock for buffer locking */
56 #define	XFS_ALLOC_FLAG_FREEING	0x00000002  /* indicate caller is freeing extents*/
57 #define	XFS_ALLOC_FLAG_NORMAP	0x00000004  /* don't modify the rmapbt */
58 #define	XFS_ALLOC_FLAG_NOSHRINK	0x00000008  /* don't shrink the freelist */
59 
60 
61 /*
62  * Argument structure for xfs_alloc routines.
63  * This is turned into a structure to avoid having 20 arguments passed
64  * down several levels of the stack.
65  */
66 typedef struct xfs_alloc_arg {
67 	struct xfs_trans *tp;		/* transaction pointer */
68 	struct xfs_mount *mp;		/* file system mount point */
69 	struct xfs_buf	*agbp;		/* buffer for a.g. freelist header */
70 	struct xfs_perag *pag;		/* per-ag struct for this agno */
71 	struct xfs_inode *ip;		/* for userdata zeroing method */
72 	xfs_fsblock_t	fsbno;		/* file system block number */
73 	xfs_agnumber_t	agno;		/* allocation group number */
74 	xfs_agblock_t	agbno;		/* allocation group-relative block # */
75 	xfs_extlen_t	minlen;		/* minimum size of extent */
76 	xfs_extlen_t	maxlen;		/* maximum size of extent */
77 	xfs_extlen_t	mod;		/* mod value for extent size */
78 	xfs_extlen_t	prod;		/* prod value for extent size */
79 	xfs_extlen_t	minleft;	/* min blocks must be left after us */
80 	xfs_extlen_t	total;		/* total blocks needed in xaction */
81 	xfs_extlen_t	alignment;	/* align answer to multiple of this */
82 	xfs_extlen_t	minalignslop;	/* slop for minlen+alignment calcs */
83 	xfs_agblock_t	min_agbno;	/* set an agbno range for NEAR allocs */
84 	xfs_agblock_t	max_agbno;	/* ... */
85 	xfs_extlen_t	len;		/* output: actual size of extent */
86 	xfs_alloctype_t	type;		/* allocation type XFS_ALLOCTYPE_... */
87 	xfs_alloctype_t	otype;		/* original allocation type */
88 	int		datatype;	/* mask defining data type treatment */
89 	char		wasdel;		/* set if allocation was prev delayed */
90 	char		wasfromfl;	/* set if allocation is from freelist */
91 	xfs_fsblock_t	firstblock;	/* io first block allocated */
92 	struct xfs_owner_info	oinfo;	/* owner of blocks being allocated */
93 	enum xfs_ag_resv_type	resv;	/* block reservation to use */
94 } xfs_alloc_arg_t;
95 
96 /*
97  * Defines for datatype
98  */
99 #define XFS_ALLOC_USERDATA		(1 << 0)/* allocation is for user data*/
100 #define XFS_ALLOC_INITIAL_USER_DATA	(1 << 1)/* special case start of file */
101 #define XFS_ALLOC_USERDATA_ZERO		(1 << 2)/* zero extent on allocation */
102 #define XFS_ALLOC_NOBUSY		(1 << 3)/* Busy extents not allowed */
103 
104 static inline bool
105 xfs_alloc_is_userdata(int datatype)
106 {
107 	return (datatype & ~XFS_ALLOC_NOBUSY) != 0;
108 }
109 
110 static inline bool
111 xfs_alloc_allow_busy_reuse(int datatype)
112 {
113 	return (datatype & XFS_ALLOC_NOBUSY) == 0;
114 }
115 
116 /* freespace limit calculations */
117 #define XFS_ALLOC_AGFL_RESERVE	4
118 unsigned int xfs_alloc_set_aside(struct xfs_mount *mp);
119 unsigned int xfs_alloc_ag_max_usable(struct xfs_mount *mp);
120 
121 xfs_extlen_t xfs_alloc_longest_free_extent(struct xfs_mount *mp,
122 		struct xfs_perag *pag, xfs_extlen_t need,
123 		xfs_extlen_t reserved);
124 unsigned int xfs_alloc_min_freelist(struct xfs_mount *mp,
125 		struct xfs_perag *pag);
126 
127 /*
128  * Compute and fill in value of m_ag_maxlevels.
129  */
130 void
131 xfs_alloc_compute_maxlevels(
132 	struct xfs_mount	*mp);	/* file system mount structure */
133 
134 /*
135  * Get a block from the freelist.
136  * Returns with the buffer for the block gotten.
137  */
138 int				/* error */
139 xfs_alloc_get_freelist(
140 	struct xfs_trans *tp,	/* transaction pointer */
141 	struct xfs_buf	*agbp,	/* buffer containing the agf structure */
142 	xfs_agblock_t	*bnop,	/* block address retrieved from freelist */
143 	int		btreeblk); /* destination is a AGF btree */
144 
145 /*
146  * Log the given fields from the agf structure.
147  */
148 void
149 xfs_alloc_log_agf(
150 	struct xfs_trans *tp,	/* transaction pointer */
151 	struct xfs_buf	*bp,	/* buffer for a.g. freelist header */
152 	int		fields);/* mask of fields to be logged (XFS_AGF_...) */
153 
154 /*
155  * Interface for inode allocation to force the pag data to be initialized.
156  */
157 int				/* error */
158 xfs_alloc_pagf_init(
159 	struct xfs_mount *mp,	/* file system mount structure */
160 	struct xfs_trans *tp,	/* transaction pointer */
161 	xfs_agnumber_t	agno,	/* allocation group number */
162 	int		flags);	/* XFS_ALLOC_FLAGS_... */
163 
164 /*
165  * Put the block on the freelist for the allocation group.
166  */
167 int				/* error */
168 xfs_alloc_put_freelist(
169 	struct xfs_trans *tp,	/* transaction pointer */
170 	struct xfs_buf	*agbp,	/* buffer for a.g. freelist header */
171 	struct xfs_buf	*agflbp,/* buffer for a.g. free block array */
172 	xfs_agblock_t	bno,	/* block being freed */
173 	int		btreeblk); /* owner was a AGF btree */
174 
175 /*
176  * Read in the allocation group header (free/alloc section).
177  */
178 int					/* error  */
179 xfs_alloc_read_agf(
180 	struct xfs_mount *mp,		/* mount point structure */
181 	struct xfs_trans *tp,		/* transaction pointer */
182 	xfs_agnumber_t	agno,		/* allocation group number */
183 	int		flags,		/* XFS_ALLOC_FLAG_... */
184 	struct xfs_buf	**bpp);		/* buffer for the ag freelist header */
185 
186 /*
187  * Allocate an extent (variable-size).
188  */
189 int				/* error */
190 xfs_alloc_vextent(
191 	xfs_alloc_arg_t	*args);	/* allocation argument structure */
192 
193 /*
194  * Free an extent.
195  */
196 int				/* error */
197 xfs_free_extent(
198 	struct xfs_trans	*tp,	/* transaction pointer */
199 	xfs_fsblock_t		bno,	/* starting block number of extent */
200 	xfs_extlen_t		len,	/* length of extent */
201 	struct xfs_owner_info	*oinfo,	/* extent owner */
202 	enum xfs_ag_resv_type	type);	/* block reservation type */
203 
204 int				/* error */
205 xfs_alloc_lookup_ge(
206 	struct xfs_btree_cur	*cur,	/* btree cursor */
207 	xfs_agblock_t		bno,	/* starting block of extent */
208 	xfs_extlen_t		len,	/* length of extent */
209 	int			*stat);	/* success/failure */
210 
211 int					/* error */
212 xfs_alloc_get_rec(
213 	struct xfs_btree_cur	*cur,	/* btree cursor */
214 	xfs_agblock_t		*bno,	/* output: starting block of extent */
215 	xfs_extlen_t		*len,	/* output: length of extent */
216 	int			*stat);	/* output: success/failure */
217 
218 int xfs_read_agf(struct xfs_mount *mp, struct xfs_trans *tp,
219 			xfs_agnumber_t agno, int flags, struct xfs_buf **bpp);
220 int xfs_alloc_fix_freelist(struct xfs_alloc_arg *args, int flags);
221 int xfs_free_extent_fix_freelist(struct xfs_trans *tp, xfs_agnumber_t agno,
222 		struct xfs_buf **agbp);
223 
224 xfs_extlen_t xfs_prealloc_blocks(struct xfs_mount *mp);
225 
226 #endif	/* __XFS_ALLOC_H__ */
227