summaryrefslogtreecommitdiffstats
path: root/fs/xfs/libxfs/xfs_bmap.h
blob: 423a34e832bdc07ab402a3f17023ac311ba1251b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
/*
 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
 * All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it would be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write the Free Software Foundation,
 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
#ifndef __XFS_BMAP_H__
#define	__XFS_BMAP_H__

struct getbmap;
struct xfs_bmbt_irec;
struct xfs_ifork;
struct xfs_inode;
struct xfs_mount;
struct xfs_trans;

extern kmem_zone_t	*xfs_bmap_free_item_zone;

/*
 * Argument structure for xfs_bmap_alloc.
 */
struct xfs_bmalloca {
	xfs_fsblock_t		*firstblock; /* i/o first block allocated */
	struct xfs_bmap_free	*flist;	/* bmap freelist */
	struct xfs_trans	*tp;	/* transaction pointer */
	struct xfs_inode	*ip;	/* incore inode pointer */
	struct xfs_bmbt_irec	prev;	/* extent before the new one */
	struct xfs_bmbt_irec	got;	/* extent after, or delayed */

	xfs_fileoff_t		offset;	/* offset in file filling in */
	xfs_extlen_t		length;	/* i/o length asked/allocated */
	xfs_fsblock_t		blkno;	/* starting block of new extent */

	struct xfs_btree_cur	*cur;	/* btree cursor */
	xfs_extnum_t		idx;	/* current extent index */
	int			nallocs;/* number of extents alloc'd */
	int			logflags;/* flags for transaction logging */

	xfs_extlen_t		total;	/* total blocks needed for xaction */
	xfs_extlen_t		minlen;	/* minimum allocation size (blocks) */
	xfs_extlen_t		minleft; /* amount must be left after alloc */
	bool			eof;	/* set if allocating past last extent */
	bool			wasdel;	/* replacing a delayed allocation */
	bool			aeof;	/* allocated space at eof */
	bool			conv;	/* overwriting unwritten extents */
	char			userdata;/* userdata mask */
	int			flags;
};

/*
 * List of extents to be free "later".
 * The list is kept sorted on xbf_startblock.
 */
typedef struct xfs_bmap_free_item
{
	xfs_fsblock_t		xbfi_startblock;/* starting fs block number */
	xfs_extlen_t		xbfi_blockcount;/* number of blocks in extent */
	struct xfs_bmap_free_item *xbfi_next;	/* link to next entry */
} xfs_bmap_free_item_t;

/*
 * Header for free extent list.
 *
 * xbf_low is used by the allocator to activate the lowspace algorithm -
 * when free space is running low the extent allocator may choose to
 * allocate an extent from an AG without leaving sufficient space for
 * a btree split when inserting the new extent.  In this case the allocator
 * will enable the lowspace algorithm which is supposed to allow further
 * allocations (such as btree splits and newroots) to allocate from
 * sequential AGs.  In order to avoid locking AGs out of order the lowspace
 * algorithm will start searching for free space from AG 0.  If the correct
 * transaction reservations have been made then this algorithm will eventually
 * find all the space it needs.
 */
typedef	struct xfs_bmap_free
{
	xfs_bmap_free_item_t	*xbf_first;	/* list of to-be-free extents */
	int			xbf_count;	/* count of items on list */
	int			xbf_low;	/* alloc in low mode */
} xfs_bmap_free_t;

#define	XFS_BMAP_MAX_NMAP	4

/*
 * Flags for xfs_bmapi_*
 */
#define XFS_BMAPI_ENTIRE	0x001	/* return entire extent, not trimmed */
#define XFS_BMAPI_METADATA	0x002	/* mapping metadata not user data */
#define XFS_BMAPI_ATTRFORK	0x004	/* use attribute fork not data */
#define XFS_BMAPI_PREALLOC	0x008	/* preallocation op: unwritten space */
#define XFS_BMAPI_IGSTATE	0x010	/* Ignore state - */
					/* combine contig. space */
#define XFS_BMAPI_CONTIG	0x020	/* must allocate only one extent */
/*
 * unwritten extent conversion - this needs write cache flushing and no additional
 * allocation alignments. When specified with XFS_BMAPI_PREALLOC it converts
 * from written to unwritten, otherwise convert from unwritten to written.
 */
#define XFS_BMAPI_CONVERT	0x040

/*
 * allocate zeroed extents - this requires all newly allocated user data extents
 * to be initialised to zero. It will be ignored if XFS_BMAPI_METADATA is set.
 * Use in conjunction with XFS_BMAPI_CONVERT to convert unwritten extents found
 * during the allocation range to zeroed written extents.
 */
#define XFS_BMAPI_ZERO		0x080

#define XFS_BMAPI_FLAGS \
	{ XFS_BMAPI_ENTIRE,	"ENTIRE" }, \
	{ XFS_BMAPI_METADATA,	"METADATA" }, \
	{ XFS_BMAPI_ATTRFORK,	"ATTRFORK" }, \
	{ XFS_BMAPI_PREALLOC,	"PREALLOC" }, \
	{ XFS_BMAPI_IGSTATE,	"IGSTATE" }, \
	{ XFS_BMAPI_CONTIG,	"CONTIG" }, \
	{ XFS_BMAPI_CONVERT,	"CONVERT" }, \
	{ XFS_BMAPI_ZERO,	"ZERO" }


static inline int xfs_bmapi_aflag(int w)
{
	return (w == XFS_ATTR_FORK ? XFS_BMAPI_ATTRFORK : 0);
}

/*
 * Special values for xfs_bmbt_irec_t br_startblock field.
 */
#define	DELAYSTARTBLOCK		((xfs_fsblock_t)-1LL)
#define	HOLESTARTBLOCK		((xfs_fsblock_t)-2LL)

static inline void xfs_bmap_init(xfs_bmap_free_t *flp, xfs_fsblock_t *fbp)
{
	((flp)->xbf_first = NULL, (flp)->xbf_count = 0, \
		(flp)->xbf_low = 0, *(fbp) = NULLFSBLOCK);
}

/*
 * Flags for xfs_bmap_add_extent*.
 */
#define BMAP_LEFT_CONTIG	(1 << 0)
#define BMAP_RIGHT_CONTIG	(1 << 1)
#define BMAP_LEFT_FILLING	(1 << 2)
#define BMAP_RIGHT_FILLING	(1 << 3)
#define BMAP_LEFT_DELAY		(1 << 4)
#define BMAP_RIGHT_DELAY	(1 << 5)
#define BMAP_LEFT_VALID		(1 << 6)
#define BMAP_RIGHT_VALID	(1 << 7)
#define BMAP_ATTRFORK		(1 << 8)

#define XFS_BMAP_EXT_FLAGS \
	{ BMAP_LEFT_CONTIG,	"LC" }, \
	{ BMAP_RIGHT_CONTIG,	"RC" }, \
	{ BMAP_LEFT_FILLING,	"LF" }, \
	{ BMAP_RIGHT_FILLING,	"RF" }, \
	{ BMAP_ATTRFORK,	"ATTR" }


/*
 * This macro is used to determine how many extents will be shifted
 * in one write transaction. We could require two splits,
 * an extent move on the first and an extent merge on the second,
 * So it is proper that one extent is shifted inside write transaction
 * at a time.
 */
#define XFS_BMAP_MAX_SHIFT_EXTENTS	1

enum shift_direction {
	SHIFT_LEFT = 0,
	SHIFT_RIGHT,
};

#ifdef DEBUG
void	xfs_bmap_trace_exlist(struct xfs_inode *ip, xfs_extnum_t cnt,
		int whichfork, unsigned long caller_ip);
#define	XFS_BMAP_TRACE_EXLIST(ip,c,w)	\
	xfs_bmap_trace_exlist(ip,c,w, _THIS_IP_)
#else
#define	XFS_BMAP_TRACE_EXLIST(ip,c,w)
#endif

int	xfs_bmap_add_attrfork(struct xfs_inode *ip, int size, int rsvd);
void	xfs_bmap_local_to_extents_empty(struct xfs_inode *ip, int whichfork);
void	xfs_bmap_add_free(xfs_fsblock_t bno, xfs_filblks_t len,
		struct xfs_bmap_free *flist, struct xfs_mount *mp);
void	xfs_bmap_cancel(struct xfs_bmap_free *flist);
int	xfs_bmap_finish(struct xfs_trans **tp, struct xfs_bmap_free *flist,
			struct xfs_inode *ip);
void	xfs_bmap_compute_maxlevels(struct xfs_mount *mp, int whichfork);
int	xfs_bmap_first_unused(struct xfs_trans *tp, struct xfs_inode *ip,
		xfs_extlen_t len, xfs_fileoff_t *unused, int whichfork);
int	xfs_bmap_last_before(struct xfs_trans *tp, struct xfs_inode *ip,
		xfs_fileoff_t *last_block, int whichfork);
int	xfs_bmap_last_offset(struct xfs_inode *ip, xfs_fileoff_t *unused,
		int whichfork);
int	xfs_bmap_one_block(struct xfs_inode *ip, int whichfork);
int	xfs_bmap_read_extents(struct xfs_trans *tp, struct xfs_inode *ip,
		int whichfork);
int	xfs_bmapi_read(struct xfs_inode *ip, xfs_fileoff_t bno,
		xfs_filblks_t len, struct xfs_bmbt_irec *mval,
		int *nmap, int flags);
int	xfs_bmapi_delay(struct xfs_inode *ip, xfs_fileoff_t bno,
		xfs_filblks_t len, struct xfs_bmbt_irec *mval,
		int *nmap, int flags);
int	xfs_bmapi_write(struct xfs_trans *tp, struct xfs_inode *ip,
		xfs_fileoff_t bno, xfs_filblks_t len, int flags,
		xfs_fsblock_t *firstblock, xfs_extlen_t total,
		struct xfs_bmbt_irec *mval, int *nmap,
		struct xfs_bmap_free *flist);
int	xfs_bunmapi(struct xfs_trans *tp, struct xfs_inode *ip,
		xfs_fileoff_t bno, xfs_filblks_t len, int flags,
		xfs_extnum_t nexts, xfs_fsblock_t *firstblock,
		struct xfs_bmap_free *flist, int *done);
int	xfs_check_nostate_extents(struct xfs_ifork *ifp, xfs_extnum_t idx,
		xfs_extnum_t num);
uint	xfs_default_attroffset(struct xfs_inode *ip);
int	xfs_bmap_shift_extents(struct xfs_trans *tp, struct xfs_inode *ip,
		xfs_fileoff_t *next_fsb, xfs_fileoff_t offset_shift_fsb,
		int *done, xfs_fileoff_t stop_fsb, xfs_fsblock_t *firstblock,
		struct xfs_bmap_free *flist, enum shift_direction direction,
		int num_exts);
int	xfs_bmap_split_extent(struct xfs_inode *ip, xfs_fileoff_t split_offset);

#endif	/* __XFS_BMAP_H__ */