xref: /openbmc/linux/fs/xfs/libxfs/xfs_alloc.h (revision 4cff79e9)
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 unsigned int xfs_agfl_size(struct xfs_mount *mp);
30 
31 /*
32  * Freespace allocation types.  Argument to xfs_alloc_[v]extent.
33  */
34 #define XFS_ALLOCTYPE_FIRST_AG	0x02	/* ... start at ag 0 */
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_FIRST_AG,	"FIRST_AG" }, \
45 	{ XFS_ALLOCTYPE_THIS_AG,	"THIS_AG" }, \
46 	{ XFS_ALLOCTYPE_START_BNO,	"START_BNO" }, \
47 	{ XFS_ALLOCTYPE_NEAR_BNO,	"NEAR_BNO" }, \
48 	{ XFS_ALLOCTYPE_THIS_BNO,	"THIS_BNO" }
49 
50 /*
51  * Flags for xfs_alloc_fix_freelist.
52  */
53 #define	XFS_ALLOC_FLAG_TRYLOCK	0x00000001  /* use trylock for buffer locking */
54 #define	XFS_ALLOC_FLAG_FREEING	0x00000002  /* indicate caller is freeing extents*/
55 #define	XFS_ALLOC_FLAG_NORMAP	0x00000004  /* don't modify the rmapbt */
56 #define	XFS_ALLOC_FLAG_NOSHRINK	0x00000008  /* don't shrink the freelist */
57 #define	XFS_ALLOC_FLAG_CHECK	0x00000010  /* test only, don't modify args */
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 	struct xfs_inode *ip;		/* for userdata zeroing method */
70 	xfs_fsblock_t	fsbno;		/* file system block number */
71 	xfs_agnumber_t	agno;		/* allocation group number */
72 	xfs_agblock_t	agbno;		/* allocation group-relative block # */
73 	xfs_extlen_t	minlen;		/* minimum size of extent */
74 	xfs_extlen_t	maxlen;		/* maximum size of extent */
75 	xfs_extlen_t	mod;		/* mod value for extent size */
76 	xfs_extlen_t	prod;		/* prod value for extent size */
77 	xfs_extlen_t	minleft;	/* min blocks must be left after us */
78 	xfs_extlen_t	total;		/* total blocks needed in xaction */
79 	xfs_extlen_t	alignment;	/* align answer to multiple of this */
80 	xfs_extlen_t	minalignslop;	/* slop for minlen+alignment calcs */
81 	xfs_agblock_t	min_agbno;	/* set an agbno range for NEAR allocs */
82 	xfs_agblock_t	max_agbno;	/* ... */
83 	xfs_extlen_t	len;		/* output: actual size of extent */
84 	xfs_alloctype_t	type;		/* allocation type XFS_ALLOCTYPE_... */
85 	xfs_alloctype_t	otype;		/* original allocation type */
86 	int		datatype;	/* mask defining data type treatment */
87 	char		wasdel;		/* set if allocation was prev delayed */
88 	char		wasfromfl;	/* set if allocation is from freelist */
89 	xfs_fsblock_t	firstblock;	/* io first block allocated */
90 	struct xfs_owner_info	oinfo;	/* owner of blocks being allocated */
91 	enum xfs_ag_resv_type	resv;	/* block reservation to use */
92 } xfs_alloc_arg_t;
93 
94 /*
95  * Defines for datatype
96  */
97 #define XFS_ALLOC_USERDATA		(1 << 0)/* allocation is for user data*/
98 #define XFS_ALLOC_INITIAL_USER_DATA	(1 << 1)/* special case start of file */
99 #define XFS_ALLOC_USERDATA_ZERO		(1 << 2)/* zero extent on allocation */
100 #define XFS_ALLOC_NOBUSY		(1 << 3)/* Busy extents not allowed */
101 
102 static inline bool
103 xfs_alloc_is_userdata(int datatype)
104 {
105 	return (datatype & ~XFS_ALLOC_NOBUSY) != 0;
106 }
107 
108 static inline bool
109 xfs_alloc_allow_busy_reuse(int datatype)
110 {
111 	return (datatype & XFS_ALLOC_NOBUSY) == 0;
112 }
113 
114 /* freespace limit calculations */
115 #define XFS_ALLOC_AGFL_RESERVE	4
116 unsigned int xfs_alloc_set_aside(struct xfs_mount *mp);
117 unsigned int xfs_alloc_ag_max_usable(struct xfs_mount *mp);
118 
119 xfs_extlen_t xfs_alloc_longest_free_extent(struct xfs_perag *pag,
120 		xfs_extlen_t need, xfs_extlen_t reserved);
121 unsigned int xfs_alloc_min_freelist(struct xfs_mount *mp,
122 		struct xfs_perag *pag);
123 
124 /*
125  * Compute and fill in value of m_ag_maxlevels.
126  */
127 void
128 xfs_alloc_compute_maxlevels(
129 	struct xfs_mount	*mp);	/* file system mount structure */
130 
131 /*
132  * Get a block from the freelist.
133  * Returns with the buffer for the block gotten.
134  */
135 int				/* error */
136 xfs_alloc_get_freelist(
137 	struct xfs_trans *tp,	/* transaction pointer */
138 	struct xfs_buf	*agbp,	/* buffer containing the agf structure */
139 	xfs_agblock_t	*bnop,	/* block address retrieved from freelist */
140 	int		btreeblk); /* destination is a AGF btree */
141 
142 /*
143  * Log the given fields from the agf structure.
144  */
145 void
146 xfs_alloc_log_agf(
147 	struct xfs_trans *tp,	/* transaction pointer */
148 	struct xfs_buf	*bp,	/* buffer for a.g. freelist header */
149 	int		fields);/* mask of fields to be logged (XFS_AGF_...) */
150 
151 /*
152  * Interface for inode allocation to force the pag data to be initialized.
153  */
154 int				/* error */
155 xfs_alloc_pagf_init(
156 	struct xfs_mount *mp,	/* file system mount structure */
157 	struct xfs_trans *tp,	/* transaction pointer */
158 	xfs_agnumber_t	agno,	/* allocation group number */
159 	int		flags);	/* XFS_ALLOC_FLAGS_... */
160 
161 /*
162  * Put the block on the freelist for the allocation group.
163  */
164 int				/* error */
165 xfs_alloc_put_freelist(
166 	struct xfs_trans *tp,	/* transaction pointer */
167 	struct xfs_buf	*agbp,	/* buffer for a.g. freelist header */
168 	struct xfs_buf	*agflbp,/* buffer for a.g. free block array */
169 	xfs_agblock_t	bno,	/* block being freed */
170 	int		btreeblk); /* owner was a AGF btree */
171 
172 /*
173  * Read in the allocation group header (free/alloc section).
174  */
175 int					/* error  */
176 xfs_alloc_read_agf(
177 	struct xfs_mount *mp,		/* mount point structure */
178 	struct xfs_trans *tp,		/* transaction pointer */
179 	xfs_agnumber_t	agno,		/* allocation group number */
180 	int		flags,		/* XFS_ALLOC_FLAG_... */
181 	struct xfs_buf	**bpp);		/* buffer for the ag freelist header */
182 
183 /*
184  * Allocate an extent (variable-size).
185  */
186 int				/* error */
187 xfs_alloc_vextent(
188 	xfs_alloc_arg_t	*args);	/* allocation argument structure */
189 
190 /*
191  * Free an extent.
192  */
193 int				/* error */
194 xfs_free_extent(
195 	struct xfs_trans	*tp,	/* transaction pointer */
196 	xfs_fsblock_t		bno,	/* starting block number of extent */
197 	xfs_extlen_t		len,	/* length of extent */
198 	struct xfs_owner_info	*oinfo,	/* extent owner */
199 	enum xfs_ag_resv_type	type);	/* block reservation type */
200 
201 int				/* error */
202 xfs_alloc_lookup_le(
203 	struct xfs_btree_cur	*cur,	/* btree cursor */
204 	xfs_agblock_t		bno,	/* starting block of extent */
205 	xfs_extlen_t		len,	/* length of extent */
206 	int			*stat);	/* success/failure */
207 
208 int				/* error */
209 xfs_alloc_lookup_ge(
210 	struct xfs_btree_cur	*cur,	/* btree cursor */
211 	xfs_agblock_t		bno,	/* starting block of extent */
212 	xfs_extlen_t		len,	/* length of extent */
213 	int			*stat);	/* success/failure */
214 
215 int					/* error */
216 xfs_alloc_get_rec(
217 	struct xfs_btree_cur	*cur,	/* btree cursor */
218 	xfs_agblock_t		*bno,	/* output: starting block of extent */
219 	xfs_extlen_t		*len,	/* output: length of extent */
220 	int			*stat);	/* output: success/failure */
221 
222 int xfs_read_agf(struct xfs_mount *mp, struct xfs_trans *tp,
223 			xfs_agnumber_t agno, int flags, struct xfs_buf **bpp);
224 int xfs_alloc_read_agfl(struct xfs_mount *mp, struct xfs_trans *tp,
225 			xfs_agnumber_t agno, struct xfs_buf **bpp);
226 int xfs_alloc_fix_freelist(struct xfs_alloc_arg *args, int flags);
227 int xfs_free_extent_fix_freelist(struct xfs_trans *tp, xfs_agnumber_t agno,
228 		struct xfs_buf **agbp);
229 
230 xfs_extlen_t xfs_prealloc_blocks(struct xfs_mount *mp);
231 
232 typedef int (*xfs_alloc_query_range_fn)(
233 	struct xfs_btree_cur		*cur,
234 	struct xfs_alloc_rec_incore	*rec,
235 	void				*priv);
236 
237 int xfs_alloc_query_range(struct xfs_btree_cur *cur,
238 		struct xfs_alloc_rec_incore *low_rec,
239 		struct xfs_alloc_rec_incore *high_rec,
240 		xfs_alloc_query_range_fn fn, void *priv);
241 int xfs_alloc_query_all(struct xfs_btree_cur *cur, xfs_alloc_query_range_fn fn,
242 		void *priv);
243 xfs_agblock_t xfs_ag_block_count(struct xfs_mount *mp, xfs_agnumber_t agno);
244 bool xfs_verify_agbno(struct xfs_mount *mp, xfs_agnumber_t agno,
245 		xfs_agblock_t agbno);
246 bool xfs_verify_fsbno(struct xfs_mount *mp, xfs_fsblock_t fsbno);
247 
248 int xfs_alloc_has_record(struct xfs_btree_cur *cur, xfs_agblock_t bno,
249 		xfs_extlen_t len, bool *exist);
250 
251 #endif	/* __XFS_ALLOC_H__ */
252