1/*
2 * Copyright (c) 2000-2006 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_BMAP_H__
19#define	__XFS_BMAP_H__
20
21struct getbmap;
22struct xfs_bmbt_irec;
23struct xfs_ifork;
24struct xfs_inode;
25struct xfs_mount;
26struct xfs_trans;
27
28extern kmem_zone_t	*xfs_bmap_free_item_zone;
29
30/*
31 * Argument structure for xfs_bmap_alloc.
32 */
33struct xfs_bmalloca {
34	xfs_fsblock_t		*firstblock; /* i/o first block allocated */
35	struct xfs_bmap_free	*flist;	/* bmap freelist */
36	struct xfs_trans	*tp;	/* transaction pointer */
37	struct xfs_inode	*ip;	/* incore inode pointer */
38	struct xfs_bmbt_irec	prev;	/* extent before the new one */
39	struct xfs_bmbt_irec	got;	/* extent after, or delayed */
40
41	xfs_fileoff_t		offset;	/* offset in file filling in */
42	xfs_extlen_t		length;	/* i/o length asked/allocated */
43	xfs_fsblock_t		blkno;	/* starting block of new extent */
44
45	struct xfs_btree_cur	*cur;	/* btree cursor */
46	xfs_extnum_t		idx;	/* current extent index */
47	int			nallocs;/* number of extents alloc'd */
48	int			logflags;/* flags for transaction logging */
49
50	xfs_extlen_t		total;	/* total blocks needed for xaction */
51	xfs_extlen_t		minlen;	/* minimum allocation size (blocks) */
52	xfs_extlen_t		minleft; /* amount must be left after alloc */
53	bool			eof;	/* set if allocating past last extent */
54	bool			wasdel;	/* replacing a delayed allocation */
55	bool			aeof;	/* allocated space at eof */
56	bool			conv;	/* overwriting unwritten extents */
57	char			userdata;/* userdata mask */
58	int			flags;
59};
60
61/*
62 * List of extents to be free "later".
63 * The list is kept sorted on xbf_startblock.
64 */
65typedef struct xfs_bmap_free_item
66{
67	xfs_fsblock_t		xbfi_startblock;/* starting fs block number */
68	xfs_extlen_t		xbfi_blockcount;/* number of blocks in extent */
69	struct xfs_bmap_free_item *xbfi_next;	/* link to next entry */
70} xfs_bmap_free_item_t;
71
72/*
73 * Header for free extent list.
74 *
75 * xbf_low is used by the allocator to activate the lowspace algorithm -
76 * when free space is running low the extent allocator may choose to
77 * allocate an extent from an AG without leaving sufficient space for
78 * a btree split when inserting the new extent.  In this case the allocator
79 * will enable the lowspace algorithm which is supposed to allow further
80 * allocations (such as btree splits and newroots) to allocate from
81 * sequential AGs.  In order to avoid locking AGs out of order the lowspace
82 * algorithm will start searching for free space from AG 0.  If the correct
83 * transaction reservations have been made then this algorithm will eventually
84 * find all the space it needs.
85 */
86typedef	struct xfs_bmap_free
87{
88	xfs_bmap_free_item_t	*xbf_first;	/* list of to-be-free extents */
89	int			xbf_count;	/* count of items on list */
90	int			xbf_low;	/* alloc in low mode */
91} xfs_bmap_free_t;
92
93#define	XFS_BMAP_MAX_NMAP	4
94
95/*
96 * Flags for xfs_bmapi_*
97 */
98#define XFS_BMAPI_ENTIRE	0x001	/* return entire extent, not trimmed */
99#define XFS_BMAPI_METADATA	0x002	/* mapping metadata not user data */
100#define XFS_BMAPI_ATTRFORK	0x004	/* use attribute fork not data */
101#define XFS_BMAPI_PREALLOC	0x008	/* preallocation op: unwritten space */
102#define XFS_BMAPI_IGSTATE	0x010	/* Ignore state - */
103					/* combine contig. space */
104#define XFS_BMAPI_CONTIG	0x020	/* must allocate only one extent */
105/*
106 * unwritten extent conversion - this needs write cache flushing and no additional
107 * allocation alignments. When specified with XFS_BMAPI_PREALLOC it converts
108 * from written to unwritten, otherwise convert from unwritten to written.
109 */
110#define XFS_BMAPI_CONVERT	0x040
111
112/*
113 * allocate zeroed extents - this requires all newly allocated user data extents
114 * to be initialised to zero. It will be ignored if XFS_BMAPI_METADATA is set.
115 * Use in conjunction with XFS_BMAPI_CONVERT to convert unwritten extents found
116 * during the allocation range to zeroed written extents.
117 */
118#define XFS_BMAPI_ZERO		0x080
119
120#define XFS_BMAPI_FLAGS \
121	{ XFS_BMAPI_ENTIRE,	"ENTIRE" }, \
122	{ XFS_BMAPI_METADATA,	"METADATA" }, \
123	{ XFS_BMAPI_ATTRFORK,	"ATTRFORK" }, \
124	{ XFS_BMAPI_PREALLOC,	"PREALLOC" }, \
125	{ XFS_BMAPI_IGSTATE,	"IGSTATE" }, \
126	{ XFS_BMAPI_CONTIG,	"CONTIG" }, \
127	{ XFS_BMAPI_CONVERT,	"CONVERT" }, \
128	{ XFS_BMAPI_ZERO,	"ZERO" }
129
130
131static inline int xfs_bmapi_aflag(int w)
132{
133	return (w == XFS_ATTR_FORK ? XFS_BMAPI_ATTRFORK : 0);
134}
135
136/*
137 * Special values for xfs_bmbt_irec_t br_startblock field.
138 */
139#define	DELAYSTARTBLOCK		((xfs_fsblock_t)-1LL)
140#define	HOLESTARTBLOCK		((xfs_fsblock_t)-2LL)
141
142static inline void xfs_bmap_init(xfs_bmap_free_t *flp, xfs_fsblock_t *fbp)
143{
144	((flp)->xbf_first = NULL, (flp)->xbf_count = 0, \
145		(flp)->xbf_low = 0, *(fbp) = NULLFSBLOCK);
146}
147
148/*
149 * Flags for xfs_bmap_add_extent*.
150 */
151#define BMAP_LEFT_CONTIG	(1 << 0)
152#define BMAP_RIGHT_CONTIG	(1 << 1)
153#define BMAP_LEFT_FILLING	(1 << 2)
154#define BMAP_RIGHT_FILLING	(1 << 3)
155#define BMAP_LEFT_DELAY		(1 << 4)
156#define BMAP_RIGHT_DELAY	(1 << 5)
157#define BMAP_LEFT_VALID		(1 << 6)
158#define BMAP_RIGHT_VALID	(1 << 7)
159#define BMAP_ATTRFORK		(1 << 8)
160
161#define XFS_BMAP_EXT_FLAGS \
162	{ BMAP_LEFT_CONTIG,	"LC" }, \
163	{ BMAP_RIGHT_CONTIG,	"RC" }, \
164	{ BMAP_LEFT_FILLING,	"LF" }, \
165	{ BMAP_RIGHT_FILLING,	"RF" }, \
166	{ BMAP_ATTRFORK,	"ATTR" }
167
168
169/*
170 * This macro is used to determine how many extents will be shifted
171 * in one write transaction. We could require two splits,
172 * an extent move on the first and an extent merge on the second,
173 * So it is proper that one extent is shifted inside write transaction
174 * at a time.
175 */
176#define XFS_BMAP_MAX_SHIFT_EXTENTS	1
177
178enum shift_direction {
179	SHIFT_LEFT = 0,
180	SHIFT_RIGHT,
181};
182
183#ifdef DEBUG
184void	xfs_bmap_trace_exlist(struct xfs_inode *ip, xfs_extnum_t cnt,
185		int whichfork, unsigned long caller_ip);
186#define	XFS_BMAP_TRACE_EXLIST(ip,c,w)	\
187	xfs_bmap_trace_exlist(ip,c,w, _THIS_IP_)
188#else
189#define	XFS_BMAP_TRACE_EXLIST(ip,c,w)
190#endif
191
192int	xfs_bmap_add_attrfork(struct xfs_inode *ip, int size, int rsvd);
193void	xfs_bmap_local_to_extents_empty(struct xfs_inode *ip, int whichfork);
194void	xfs_bmap_add_free(xfs_fsblock_t bno, xfs_filblks_t len,
195		struct xfs_bmap_free *flist, struct xfs_mount *mp);
196void	xfs_bmap_cancel(struct xfs_bmap_free *flist);
197int	xfs_bmap_finish(struct xfs_trans **tp, struct xfs_bmap_free *flist,
198			int *committed);
199void	xfs_bmap_compute_maxlevels(struct xfs_mount *mp, int whichfork);
200int	xfs_bmap_first_unused(struct xfs_trans *tp, struct xfs_inode *ip,
201		xfs_extlen_t len, xfs_fileoff_t *unused, int whichfork);
202int	xfs_bmap_last_before(struct xfs_trans *tp, struct xfs_inode *ip,
203		xfs_fileoff_t *last_block, int whichfork);
204int	xfs_bmap_last_offset(struct xfs_inode *ip, xfs_fileoff_t *unused,
205		int whichfork);
206int	xfs_bmap_one_block(struct xfs_inode *ip, int whichfork);
207int	xfs_bmap_read_extents(struct xfs_trans *tp, struct xfs_inode *ip,
208		int whichfork);
209int	xfs_bmapi_read(struct xfs_inode *ip, xfs_fileoff_t bno,
210		xfs_filblks_t len, struct xfs_bmbt_irec *mval,
211		int *nmap, int flags);
212int	xfs_bmapi_delay(struct xfs_inode *ip, xfs_fileoff_t bno,
213		xfs_filblks_t len, struct xfs_bmbt_irec *mval,
214		int *nmap, int flags);
215int	xfs_bmapi_write(struct xfs_trans *tp, struct xfs_inode *ip,
216		xfs_fileoff_t bno, xfs_filblks_t len, int flags,
217		xfs_fsblock_t *firstblock, xfs_extlen_t total,
218		struct xfs_bmbt_irec *mval, int *nmap,
219		struct xfs_bmap_free *flist);
220int	xfs_bunmapi(struct xfs_trans *tp, struct xfs_inode *ip,
221		xfs_fileoff_t bno, xfs_filblks_t len, int flags,
222		xfs_extnum_t nexts, xfs_fsblock_t *firstblock,
223		struct xfs_bmap_free *flist, int *done);
224int	xfs_check_nostate_extents(struct xfs_ifork *ifp, xfs_extnum_t idx,
225		xfs_extnum_t num);
226uint	xfs_default_attroffset(struct xfs_inode *ip);
227int	xfs_bmap_shift_extents(struct xfs_trans *tp, struct xfs_inode *ip,
228		xfs_fileoff_t *next_fsb, xfs_fileoff_t offset_shift_fsb,
229		int *done, xfs_fileoff_t stop_fsb, xfs_fsblock_t *firstblock,
230		struct xfs_bmap_free *flist, enum shift_direction direction,
231		int num_exts);
232int	xfs_bmap_split_extent(struct xfs_inode *ip, xfs_fileoff_t split_offset);
233
234#endif	/* __XFS_BMAP_H__ */
235