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 * List of extents to be free "later".
32 * The list is kept sorted on xbf_startblock.
33 */
34 typedef struct xfs_bmap_free_item
35 {
36 xfs_fsblock_t xbfi_startblock;/* starting fs block number */
37 xfs_extlen_t xbfi_blockcount;/* number of blocks in extent */
38 struct xfs_bmap_free_item *xbfi_next; /* link to next entry */
39 } xfs_bmap_free_item_t;
40
41 /*
42 * Header for free extent list.
43 *
44 * xbf_low is used by the allocator to activate the lowspace algorithm -
45 * when free space is running low the extent allocator may choose to
46 * allocate an extent from an AG without leaving sufficient space for
47 * a btree split when inserting the new extent. In this case the allocator
48 * will enable the lowspace algorithm which is supposed to allow further
49 * allocations (such as btree splits and newroots) to allocate from
50 * sequential AGs. In order to avoid locking AGs out of order the lowspace
51 * algorithm will start searching for free space from AG 0. If the correct
52 * transaction reservations have been made then this algorithm will eventually
53 * find all the space it needs.
54 */
55 typedef struct xfs_bmap_free
56 {
57 xfs_bmap_free_item_t *xbf_first; /* list of to-be-free extents */
58 int xbf_count; /* count of items on list */
59 int xbf_low; /* alloc in low mode */
60 } xfs_bmap_free_t;
61
62 #define XFS_BMAP_MAX_NMAP 4
63
64 /*
65 * Flags for xfs_bmapi
66 */
67 #define XFS_BMAPI_WRITE 0x001 /* write operation: allocate space */
68 #define XFS_BMAPI_DELAY 0x002 /* delayed write operation */
69 #define XFS_BMAPI_ENTIRE 0x004 /* return entire extent, not trimmed */
70 #define XFS_BMAPI_METADATA 0x008 /* mapping metadata not user data */
71 #define XFS_BMAPI_ATTRFORK 0x010 /* use attribute fork not data */
72 #define XFS_BMAPI_RSVBLOCKS 0x020 /* OK to alloc. reserved data blocks */
73 #define XFS_BMAPI_PREALLOC 0x040 /* preallocation op: unwritten space */
74 #define XFS_BMAPI_IGSTATE 0x080 /* Ignore state - */
75 /* combine contig. space */
76 #define XFS_BMAPI_CONTIG 0x100 /* must allocate only one extent */
77 /*
78 * unwritten extent conversion - this needs write cache flushing and no additional
79 * allocation alignments. When specified with XFS_BMAPI_PREALLOC it converts
80 * from written to unwritten, otherwise convert from unwritten to written.
81 */
82 #define XFS_BMAPI_CONVERT 0x200
83
84 #define XFS_BMAPI_FLAGS \
85 { XFS_BMAPI_WRITE, "WRITE" }, \
86 { XFS_BMAPI_DELAY, "DELAY" }, \
87 { XFS_BMAPI_ENTIRE, "ENTIRE" }, \
88 { XFS_BMAPI_METADATA, "METADATA" }, \
89 { XFS_BMAPI_ATTRFORK, "ATTRFORK" }, \
90 { XFS_BMAPI_RSVBLOCKS, "RSVBLOCKS" }, \
91 { XFS_BMAPI_PREALLOC, "PREALLOC" }, \
92 { XFS_BMAPI_IGSTATE, "IGSTATE" }, \
93 { XFS_BMAPI_CONTIG, "CONTIG" }, \
94 { XFS_BMAPI_CONVERT, "CONVERT" }
95
96
xfs_bmapi_aflag(int w)97 static inline int xfs_bmapi_aflag(int w)
98 {
99 return (w == XFS_ATTR_FORK ? XFS_BMAPI_ATTRFORK : 0);
100 }
101
102 /*
103 * Special values for xfs_bmbt_irec_t br_startblock field.
104 */
105 #define DELAYSTARTBLOCK ((xfs_fsblock_t)-1LL)
106 #define HOLESTARTBLOCK ((xfs_fsblock_t)-2LL)
107
xfs_bmap_init(xfs_bmap_free_t * flp,xfs_fsblock_t * fbp)108 static inline void xfs_bmap_init(xfs_bmap_free_t *flp, xfs_fsblock_t *fbp)
109 {
110 ((flp)->xbf_first = NULL, (flp)->xbf_count = 0, \
111 (flp)->xbf_low = 0, *(fbp) = NULLFSBLOCK);
112 }
113
114 /*
115 * Argument structure for xfs_bmap_alloc.
116 */
117 typedef struct xfs_bmalloca {
118 xfs_fsblock_t firstblock; /* i/o first block allocated */
119 xfs_fsblock_t rval; /* starting block of new extent */
120 xfs_fileoff_t off; /* offset in file filling in */
121 struct xfs_trans *tp; /* transaction pointer */
122 struct xfs_inode *ip; /* incore inode pointer */
123 struct xfs_bmbt_irec *prevp; /* extent before the new one */
124 struct xfs_bmbt_irec *gotp; /* extent after, or delayed */
125 xfs_extlen_t alen; /* i/o length asked/allocated */
126 xfs_extlen_t total; /* total blocks needed for xaction */
127 xfs_extlen_t minlen; /* minimum allocation size (blocks) */
128 xfs_extlen_t minleft; /* amount must be left after alloc */
129 char eof; /* set if allocating past last extent */
130 char wasdel; /* replacing a delayed allocation */
131 char userdata;/* set if is user data */
132 char low; /* low on space, using seq'l ags */
133 char aeof; /* allocated space at eof */
134 char conv; /* overwriting unwritten extents */
135 } xfs_bmalloca_t;
136
137 /*
138 * Flags for xfs_bmap_add_extent*.
139 */
140 #define BMAP_LEFT_CONTIG (1 << 0)
141 #define BMAP_RIGHT_CONTIG (1 << 1)
142 #define BMAP_LEFT_FILLING (1 << 2)
143 #define BMAP_RIGHT_FILLING (1 << 3)
144 #define BMAP_LEFT_DELAY (1 << 4)
145 #define BMAP_RIGHT_DELAY (1 << 5)
146 #define BMAP_LEFT_VALID (1 << 6)
147 #define BMAP_RIGHT_VALID (1 << 7)
148 #define BMAP_ATTRFORK (1 << 8)
149
150 #define XFS_BMAP_EXT_FLAGS \
151 { BMAP_LEFT_CONTIG, "LC" }, \
152 { BMAP_RIGHT_CONTIG, "RC" }, \
153 { BMAP_LEFT_FILLING, "LF" }, \
154 { BMAP_RIGHT_FILLING, "RF" }, \
155 { BMAP_ATTRFORK, "ATTR" }
156
157 /*
158 * Add bmap trace insert entries for all the contents of the extent list.
159 *
160 * Quite excessive tracing. Only do this for debug builds.
161 */
162 #if defined(__KERNEL) && defined(DEBUG)
163 void
164 xfs_bmap_trace_exlist(
165 struct xfs_inode *ip, /* incore inode pointer */
166 xfs_extnum_t cnt, /* count of entries in list */
167 int whichfork,
168 unsigned long caller_ip); /* data or attr fork */
169 #define XFS_BMAP_TRACE_EXLIST(ip,c,w) \
170 xfs_bmap_trace_exlist(ip,c,w, _THIS_IP_)
171 #else
172 #define XFS_BMAP_TRACE_EXLIST(ip,c,w)
173 #endif
174
175 /*
176 * Convert inode from non-attributed to attributed.
177 * Must not be in a transaction, ip must not be locked.
178 */
179 int /* error code */
180 xfs_bmap_add_attrfork(
181 struct xfs_inode *ip, /* incore inode pointer */
182 int size, /* space needed for new attribute */
183 int rsvd); /* flag for reserved block allocation */
184
185 /*
186 * Add the extent to the list of extents to be free at transaction end.
187 * The list is maintained sorted (by block number).
188 */
189 void
190 xfs_bmap_add_free(
191 xfs_fsblock_t bno, /* fs block number of extent */
192 xfs_filblks_t len, /* length of extent */
193 xfs_bmap_free_t *flist, /* list of extents */
194 struct xfs_mount *mp); /* mount point structure */
195
196 /*
197 * Routine to clean up the free list data structure when
198 * an error occurs during a transaction.
199 */
200 void
201 xfs_bmap_cancel(
202 xfs_bmap_free_t *flist); /* free list to clean up */
203
204 /*
205 * Compute and fill in the value of the maximum depth of a bmap btree
206 * in this filesystem. Done once, during mount.
207 */
208 void
209 xfs_bmap_compute_maxlevels(
210 struct xfs_mount *mp, /* file system mount structure */
211 int whichfork); /* data or attr fork */
212
213 /*
214 * Returns the file-relative block number of the first unused block in the file.
215 * This is the lowest-address hole if the file has holes, else the first block
216 * past the end of file.
217 */
218 int /* error */
219 xfs_bmap_first_unused(
220 struct xfs_trans *tp, /* transaction pointer */
221 struct xfs_inode *ip, /* incore inode */
222 xfs_extlen_t len, /* size of hole to find */
223 xfs_fileoff_t *unused, /* unused block num */
224 int whichfork); /* data or attr fork */
225
226 /*
227 * Returns the file-relative block number of the last block + 1 before
228 * last_block (input value) in the file.
229 * This is not based on i_size, it is based on the extent list.
230 * Returns 0 for local files, as they do not have an extent list.
231 */
232 int /* error */
233 xfs_bmap_last_before(
234 struct xfs_trans *tp, /* transaction pointer */
235 struct xfs_inode *ip, /* incore inode */
236 xfs_fileoff_t *last_block, /* last block */
237 int whichfork); /* data or attr fork */
238
239 /*
240 * Returns the file-relative block number of the first block past eof in
241 * the file. This is not based on i_size, it is based on the extent list.
242 * Returns 0 for local files, as they do not have an extent list.
243 */
244 int /* error */
245 xfs_bmap_last_offset(
246 struct xfs_trans *tp, /* transaction pointer */
247 struct xfs_inode *ip, /* incore inode */
248 xfs_fileoff_t *unused, /* last block num */
249 int whichfork); /* data or attr fork */
250
251 /*
252 * Returns whether the selected fork of the inode has exactly one
253 * block or not. For the data fork we check this matches di_size,
254 * implying the file's range is 0..bsize-1.
255 */
256 int
257 xfs_bmap_one_block(
258 struct xfs_inode *ip, /* incore inode */
259 int whichfork); /* data or attr fork */
260
261 /*
262 * Read in the extents to iu_extents.
263 * All inode fields are set up by caller, we just traverse the btree
264 * and copy the records in.
265 */
266 int /* error */
267 xfs_bmap_read_extents(
268 struct xfs_trans *tp, /* transaction pointer */
269 struct xfs_inode *ip, /* incore inode */
270 int whichfork); /* data or attr fork */
271
272 /*
273 * Map file blocks to filesystem blocks.
274 * File range is given by the bno/len pair.
275 * Adds blocks to file if a write ("flags & XFS_BMAPI_WRITE" set)
276 * into a hole or past eof.
277 * Only allocates blocks from a single allocation group,
278 * to avoid locking problems.
279 * The returned value in "firstblock" from the first call in a transaction
280 * must be remembered and presented to subsequent calls in "firstblock".
281 * An upper bound for the number of blocks to be allocated is supplied to
282 * the first call in "total"; if no allocation group has that many free
283 * blocks then the call will fail (return NULLFSBLOCK in "firstblock").
284 */
285 int /* error */
286 xfs_bmapi(
287 struct xfs_trans *tp, /* transaction pointer */
288 struct xfs_inode *ip, /* incore inode */
289 xfs_fileoff_t bno, /* starting file offs. mapped */
290 xfs_filblks_t len, /* length to map in file */
291 int flags, /* XFS_BMAPI_... */
292 xfs_fsblock_t *firstblock, /* first allocated block
293 controls a.g. for allocs */
294 xfs_extlen_t total, /* total blocks needed */
295 struct xfs_bmbt_irec *mval, /* output: map values */
296 int *nmap, /* i/o: mval size/count */
297 xfs_bmap_free_t *flist); /* i/o: list extents to free */
298
299 /*
300 * Map file blocks to filesystem blocks, simple version.
301 * One block only, read-only.
302 * For flags, only the XFS_BMAPI_ATTRFORK flag is examined.
303 * For the other flag values, the effect is as if XFS_BMAPI_METADATA
304 * was set and all the others were clear.
305 */
306 int /* error */
307 xfs_bmapi_single(
308 struct xfs_trans *tp, /* transaction pointer */
309 struct xfs_inode *ip, /* incore inode */
310 int whichfork, /* data or attr fork */
311 xfs_fsblock_t *fsb, /* output: mapped block */
312 xfs_fileoff_t bno); /* starting file offs. mapped */
313
314 /*
315 * Unmap (remove) blocks from a file.
316 * If nexts is nonzero then the number of extents to remove is limited to
317 * that value. If not all extents in the block range can be removed then
318 * *done is set.
319 */
320 int /* error */
321 xfs_bunmapi(
322 struct xfs_trans *tp, /* transaction pointer */
323 struct xfs_inode *ip, /* incore inode */
324 xfs_fileoff_t bno, /* starting offset to unmap */
325 xfs_filblks_t len, /* length to unmap in file */
326 int flags, /* XFS_BMAPI_... */
327 xfs_extnum_t nexts, /* number of extents max */
328 xfs_fsblock_t *firstblock, /* first allocated block
329 controls a.g. for allocs */
330 xfs_bmap_free_t *flist, /* i/o: list extents to free */
331 int *done); /* set if not done yet */
332
333 /*
334 * Check an extent list, which has just been read, for
335 * any bit in the extent flag field.
336 */
337 int
338 xfs_check_nostate_extents(
339 struct xfs_ifork *ifp,
340 xfs_extnum_t idx,
341 xfs_extnum_t num);
342
343 uint
344 xfs_default_attroffset(
345 struct xfs_inode *ip);
346
347 #ifdef __KERNEL__
348
349 /*
350 * Routine to be called at transaction's end by xfs_bmapi, xfs_bunmapi
351 * caller. Frees all the extents that need freeing, which must be done
352 * last due to locking considerations.
353 *
354 * Return 1 if the given transaction was committed and a new one allocated,
355 * and 0 otherwise.
356 */
357 int /* error */
358 xfs_bmap_finish(
359 struct xfs_trans **tp, /* transaction pointer addr */
360 xfs_bmap_free_t *flist, /* i/o: list extents to free */
361 int *committed); /* xact committed or not */
362
363 /* bmap to userspace formatter - copy to user & advance pointer */
364 typedef int (*xfs_bmap_format_t)(void **, struct getbmapx *, int *);
365
366 /*
367 * Get inode's extents as described in bmv, and format for output.
368 */
369 int /* error code */
370 xfs_getbmap(
371 xfs_inode_t *ip,
372 struct getbmapx *bmv, /* user bmap structure */
373 xfs_bmap_format_t formatter, /* format to user */
374 void *arg); /* formatter arg */
375
376 /*
377 * Check if the endoff is outside the last extent. If so the caller will grow
378 * the allocation to a stripe unit boundary
379 */
380 int
381 xfs_bmap_eof(
382 struct xfs_inode *ip,
383 xfs_fileoff_t endoff,
384 int whichfork,
385 int *eof);
386
387 /*
388 * Count fsblocks of the given fork.
389 */
390 int
391 xfs_bmap_count_blocks(
392 xfs_trans_t *tp,
393 struct xfs_inode *ip,
394 int whichfork,
395 int *count);
396
397 int
398 xfs_bmap_punch_delalloc_range(
399 struct xfs_inode *ip,
400 xfs_fileoff_t start_fsb,
401 xfs_fileoff_t length);
402 #endif /* __KERNEL__ */
403
404 #endif /* __XFS_BMAP_H__ */
405