Merge master.kernel.org:/home/rmk/linux-2.6-mmc
[linux-2.6/mini2440.git] / fs / xfs / xfs_bmap.h
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1 /*
2 * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
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.
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.
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
18 #ifndef __XFS_BMAP_H__
19 #define __XFS_BMAP_H__
21 struct getbmap;
22 struct xfs_bmbt_irec;
23 struct xfs_inode;
24 struct xfs_mount;
25 struct xfs_trans;
28 * List of extents to be free "later".
29 * The list is kept sorted on xbf_startblock.
31 typedef struct xfs_bmap_free_item
33 xfs_fsblock_t xbfi_startblock;/* starting fs block number */
34 xfs_extlen_t xbfi_blockcount;/* number of blocks in extent */
35 struct xfs_bmap_free_item *xbfi_next; /* link to next entry */
36 } xfs_bmap_free_item_t;
39 * Header for free extent list.
41 typedef struct xfs_bmap_free
43 xfs_bmap_free_item_t *xbf_first; /* list of to-be-free extents */
44 int xbf_count; /* count of items on list */
45 int xbf_low; /* kludge: alloc in low mode */
46 } xfs_bmap_free_t;
48 #define XFS_BMAP_MAX_NMAP 4
51 * Flags for xfs_bmapi
53 #define XFS_BMAPI_WRITE 0x001 /* write operation: allocate space */
54 #define XFS_BMAPI_DELAY 0x002 /* delayed write operation */
55 #define XFS_BMAPI_ENTIRE 0x004 /* return entire extent, not trimmed */
56 #define XFS_BMAPI_METADATA 0x008 /* mapping metadata not user data */
57 #define XFS_BMAPI_EXACT 0x010 /* allocate only to spec'd bounds */
58 #define XFS_BMAPI_ATTRFORK 0x020 /* use attribute fork not data */
59 #define XFS_BMAPI_ASYNC 0x040 /* bunmapi xactions can be async */
60 #define XFS_BMAPI_RSVBLOCKS 0x080 /* OK to alloc. reserved data blocks */
61 #define XFS_BMAPI_PREALLOC 0x100 /* preallocation op: unwritten space */
62 #define XFS_BMAPI_IGSTATE 0x200 /* Ignore state - */
63 /* combine contig. space */
64 #define XFS_BMAPI_CONTIG 0x400 /* must allocate only one extent */
66 #define XFS_BMAPI_AFLAG(w) xfs_bmapi_aflag(w)
67 static inline int xfs_bmapi_aflag(int w)
69 return (w == XFS_ATTR_FORK ? XFS_BMAPI_ATTRFORK : 0);
73 * Special values for xfs_bmbt_irec_t br_startblock field.
75 #define DELAYSTARTBLOCK ((xfs_fsblock_t)-1LL)
76 #define HOLESTARTBLOCK ((xfs_fsblock_t)-2LL)
78 #define XFS_BMAP_INIT(flp,fbp) xfs_bmap_init(flp,fbp)
79 static inline void xfs_bmap_init(xfs_bmap_free_t *flp, xfs_fsblock_t *fbp)
81 ((flp)->xbf_first = NULL, (flp)->xbf_count = 0, \
82 (flp)->xbf_low = 0, *(fbp) = NULLFSBLOCK);
86 * Argument structure for xfs_bmap_alloc.
88 typedef struct xfs_bmalloca {
89 xfs_fsblock_t firstblock; /* i/o first block allocated */
90 xfs_fsblock_t rval; /* starting block of new extent */
91 xfs_fileoff_t off; /* offset in file filling in */
92 struct xfs_trans *tp; /* transaction pointer */
93 struct xfs_inode *ip; /* incore inode pointer */
94 struct xfs_bmbt_irec *prevp; /* extent before the new one */
95 struct xfs_bmbt_irec *gotp; /* extent after, or delayed */
96 xfs_extlen_t alen; /* i/o length asked/allocated */
97 xfs_extlen_t total; /* total blocks needed for xaction */
98 xfs_extlen_t minlen; /* mininum allocation size (blocks) */
99 xfs_extlen_t minleft; /* amount must be left after alloc */
100 char eof; /* set if allocating past last extent */
101 char wasdel; /* replacing a delayed allocation */
102 char userdata;/* set if is user data */
103 char low; /* low on space, using seq'l ags */
104 char aeof; /* allocated space at eof */
105 } xfs_bmalloca_t;
107 #ifdef __KERNEL__
109 #if defined(XFS_BMAP_TRACE)
111 * Trace operations for bmap extent tracing
113 #define XFS_BMAP_KTRACE_DELETE 1
114 #define XFS_BMAP_KTRACE_INSERT 2
115 #define XFS_BMAP_KTRACE_PRE_UP 3
116 #define XFS_BMAP_KTRACE_POST_UP 4
118 #define XFS_BMAP_TRACE_SIZE 4096 /* size of global trace buffer */
119 #define XFS_BMAP_KTRACE_SIZE 32 /* size of per-inode trace buffer */
120 extern ktrace_t *xfs_bmap_trace_buf;
123 * Add bmap trace insert entries for all the contents of the extent list.
125 void
126 xfs_bmap_trace_exlist(
127 char *fname, /* function name */
128 struct xfs_inode *ip, /* incore inode pointer */
129 xfs_extnum_t cnt, /* count of entries in list */
130 int whichfork); /* data or attr fork */
131 #else
132 #define xfs_bmap_trace_exlist(f,ip,c,w)
133 #endif
136 * Convert inode from non-attributed to attributed.
137 * Must not be in a transaction, ip must not be locked.
139 int /* error code */
140 xfs_bmap_add_attrfork(
141 struct xfs_inode *ip, /* incore inode pointer */
142 int size, /* space needed for new attribute */
143 int rsvd); /* flag for reserved block allocation */
146 * Add the extent to the list of extents to be free at transaction end.
147 * The list is maintained sorted (by block number).
149 void
150 xfs_bmap_add_free(
151 xfs_fsblock_t bno, /* fs block number of extent */
152 xfs_filblks_t len, /* length of extent */
153 xfs_bmap_free_t *flist, /* list of extents */
154 struct xfs_mount *mp); /* mount point structure */
157 * Routine to clean up the free list data structure when
158 * an error occurs during a transaction.
160 void
161 xfs_bmap_cancel(
162 xfs_bmap_free_t *flist); /* free list to clean up */
165 * Compute and fill in the value of the maximum depth of a bmap btree
166 * in this filesystem. Done once, during mount.
168 void
169 xfs_bmap_compute_maxlevels(
170 struct xfs_mount *mp, /* file system mount structure */
171 int whichfork); /* data or attr fork */
174 * Routine to be called at transaction's end by xfs_bmapi, xfs_bunmapi
175 * caller. Frees all the extents that need freeing, which must be done
176 * last due to locking considerations.
178 * Return 1 if the given transaction was committed and a new one allocated,
179 * and 0 otherwise.
181 int /* error */
182 xfs_bmap_finish(
183 struct xfs_trans **tp, /* transaction pointer addr */
184 xfs_bmap_free_t *flist, /* i/o: list extents to free */
185 xfs_fsblock_t firstblock, /* controlled a.g. for allocs */
186 int *committed); /* xact committed or not */
189 * Returns the file-relative block number of the first unused block in the file.
190 * This is the lowest-address hole if the file has holes, else the first block
191 * past the end of file.
193 int /* error */
194 xfs_bmap_first_unused(
195 struct xfs_trans *tp, /* transaction pointer */
196 struct xfs_inode *ip, /* incore inode */
197 xfs_extlen_t len, /* size of hole to find */
198 xfs_fileoff_t *unused, /* unused block num */
199 int whichfork); /* data or attr fork */
202 * Returns the file-relative block number of the last block + 1 before
203 * last_block (input value) in the file.
204 * This is not based on i_size, it is based on the extent list.
205 * Returns 0 for local files, as they do not have an extent list.
207 int /* error */
208 xfs_bmap_last_before(
209 struct xfs_trans *tp, /* transaction pointer */
210 struct xfs_inode *ip, /* incore inode */
211 xfs_fileoff_t *last_block, /* last block */
212 int whichfork); /* data or attr fork */
215 * Returns the file-relative block number of the first block past eof in
216 * the file. This is not based on i_size, it is based on the extent list.
217 * Returns 0 for local files, as they do not have an extent list.
219 int /* error */
220 xfs_bmap_last_offset(
221 struct xfs_trans *tp, /* transaction pointer */
222 struct xfs_inode *ip, /* incore inode */
223 xfs_fileoff_t *unused, /* last block num */
224 int whichfork); /* data or attr fork */
227 * Returns whether the selected fork of the inode has exactly one
228 * block or not. For the data fork we check this matches di_size,
229 * implying the file's range is 0..bsize-1.
232 xfs_bmap_one_block(
233 struct xfs_inode *ip, /* incore inode */
234 int whichfork); /* data or attr fork */
237 * Read in the extents to iu_extents.
238 * All inode fields are set up by caller, we just traverse the btree
239 * and copy the records in.
241 int /* error */
242 xfs_bmap_read_extents(
243 struct xfs_trans *tp, /* transaction pointer */
244 struct xfs_inode *ip, /* incore inode */
245 int whichfork); /* data or attr fork */
248 * Map file blocks to filesystem blocks.
249 * File range is given by the bno/len pair.
250 * Adds blocks to file if a write ("flags & XFS_BMAPI_WRITE" set)
251 * into a hole or past eof.
252 * Only allocates blocks from a single allocation group,
253 * to avoid locking problems.
254 * The returned value in "firstblock" from the first call in a transaction
255 * must be remembered and presented to subsequent calls in "firstblock".
256 * An upper bound for the number of blocks to be allocated is supplied to
257 * the first call in "total"; if no allocation group has that many free
258 * blocks then the call will fail (return NULLFSBLOCK in "firstblock").
260 int /* error */
261 xfs_bmapi(
262 struct xfs_trans *tp, /* transaction pointer */
263 struct xfs_inode *ip, /* incore inode */
264 xfs_fileoff_t bno, /* starting file offs. mapped */
265 xfs_filblks_t len, /* length to map in file */
266 int flags, /* XFS_BMAPI_... */
267 xfs_fsblock_t *firstblock, /* first allocated block
268 controls a.g. for allocs */
269 xfs_extlen_t total, /* total blocks needed */
270 struct xfs_bmbt_irec *mval, /* output: map values */
271 int *nmap, /* i/o: mval size/count */
272 xfs_bmap_free_t *flist); /* i/o: list extents to free */
275 * Map file blocks to filesystem blocks, simple version.
276 * One block only, read-only.
277 * For flags, only the XFS_BMAPI_ATTRFORK flag is examined.
278 * For the other flag values, the effect is as if XFS_BMAPI_METADATA
279 * was set and all the others were clear.
281 int /* error */
282 xfs_bmapi_single(
283 struct xfs_trans *tp, /* transaction pointer */
284 struct xfs_inode *ip, /* incore inode */
285 int whichfork, /* data or attr fork */
286 xfs_fsblock_t *fsb, /* output: mapped block */
287 xfs_fileoff_t bno); /* starting file offs. mapped */
290 * Unmap (remove) blocks from a file.
291 * If nexts is nonzero then the number of extents to remove is limited to
292 * that value. If not all extents in the block range can be removed then
293 * *done is set.
295 int /* error */
296 xfs_bunmapi(
297 struct xfs_trans *tp, /* transaction pointer */
298 struct xfs_inode *ip, /* incore inode */
299 xfs_fileoff_t bno, /* starting offset to unmap */
300 xfs_filblks_t len, /* length to unmap in file */
301 int flags, /* XFS_BMAPI_... */
302 xfs_extnum_t nexts, /* number of extents max */
303 xfs_fsblock_t *firstblock, /* first allocated block
304 controls a.g. for allocs */
305 xfs_bmap_free_t *flist, /* i/o: list extents to free */
306 int *done); /* set if not done yet */
309 * Fcntl interface to xfs_bmapi.
311 int /* error code */
312 xfs_getbmap(
313 bhv_desc_t *bdp, /* XFS behavior descriptor*/
314 struct getbmap *bmv, /* user bmap structure */
315 void __user *ap, /* pointer to user's array */
316 int iflags); /* interface flags */
319 * Check if the endoff is outside the last extent. If so the caller will grow
320 * the allocation to a stripe unit boundary
323 xfs_bmap_eof(
324 struct xfs_inode *ip,
325 xfs_fileoff_t endoff,
326 int whichfork,
327 int *eof);
330 * Count fsblocks of the given fork.
333 xfs_bmap_count_blocks(
334 xfs_trans_t *tp,
335 struct xfs_inode *ip,
336 int whichfork,
337 int *count);
340 * Check an extent list, which has just been read, for
341 * any bit in the extent flag field.
344 xfs_check_nostate_extents(
345 xfs_bmbt_rec_t *ep,
346 xfs_extnum_t num);
348 #endif /* __KERNEL__ */
350 #endif /* __XFS_BMAP_H__ */