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
21 struct getbmap;
22 struct xfs_bmbt_irec;
23 struct xfs_ifork;
24 struct xfs_inode;
25 struct xfs_mount;
26 struct xfs_trans;
27
28 extern kmem_zone_t *xfs_bmap_free_item_zone;
29
30 /*
31 * Argument structure for xfs_bmap_alloc.
32 */
33 struct 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 */
65 typedef 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 */
86 typedef 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
xfs_bmapi_aflag(int w)131 static 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
xfs_bmap_init(xfs_bmap_free_t * flp,xfs_fsblock_t * fbp)142 static 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
178 enum shift_direction {
179 SHIFT_LEFT = 0,
180 SHIFT_RIGHT,
181 };
182
183 #ifdef DEBUG
184 void 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
192 int xfs_bmap_add_attrfork(struct xfs_inode *ip, int size, int rsvd);
193 void xfs_bmap_local_to_extents_empty(struct xfs_inode *ip, int whichfork);
194 void xfs_bmap_add_free(xfs_fsblock_t bno, xfs_filblks_t len,
195 struct xfs_bmap_free *flist, struct xfs_mount *mp);
196 void xfs_bmap_cancel(struct xfs_bmap_free *flist);
197 int xfs_bmap_finish(struct xfs_trans **tp, struct xfs_bmap_free *flist,
198 int *committed);
199 void xfs_bmap_compute_maxlevels(struct xfs_mount *mp, int whichfork);
200 int xfs_bmap_first_unused(struct xfs_trans *tp, struct xfs_inode *ip,
201 xfs_extlen_t len, xfs_fileoff_t *unused, int whichfork);
202 int xfs_bmap_last_before(struct xfs_trans *tp, struct xfs_inode *ip,
203 xfs_fileoff_t *last_block, int whichfork);
204 int xfs_bmap_last_offset(struct xfs_inode *ip, xfs_fileoff_t *unused,
205 int whichfork);
206 int xfs_bmap_one_block(struct xfs_inode *ip, int whichfork);
207 int xfs_bmap_read_extents(struct xfs_trans *tp, struct xfs_inode *ip,
208 int whichfork);
209 int 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);
212 int 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);
215 int 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);
220 int 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);
224 int xfs_check_nostate_extents(struct xfs_ifork *ifp, xfs_extnum_t idx,
225 xfs_extnum_t num);
226 uint xfs_default_attroffset(struct xfs_inode *ip);
227 int 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);
232 int xfs_bmap_split_extent(struct xfs_inode *ip, xfs_fileoff_t split_offset);
233
234 #endif /* __XFS_BMAP_H__ */
235