2 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
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__
28 extern kmem_zone_t
*xfs_bmap_free_item_zone
;
31 * DELTA: describe a change to the in-core extent list.
33 * Internally the use of xed_blockount is somewhat funky.
34 * xed_blockcount contains an offset much of the time because this
35 * makes merging changes easier. (xfs_fileoff_t and xfs_filblks_t are
36 * the same underlying type).
38 typedef struct xfs_extdelta
40 xfs_fileoff_t xed_startoff
; /* offset of range */
41 xfs_filblks_t xed_blockcount
; /* blocks in range */
45 * List of extents to be free "later".
46 * The list is kept sorted on xbf_startblock.
48 typedef struct xfs_bmap_free_item
50 xfs_fsblock_t xbfi_startblock
;/* starting fs block number */
51 xfs_extlen_t xbfi_blockcount
;/* number of blocks in extent */
52 struct xfs_bmap_free_item
*xbfi_next
; /* link to next entry */
53 } xfs_bmap_free_item_t
;
56 * Header for free extent list.
58 * xbf_low is used by the allocator to activate the lowspace algorithm -
59 * when free space is running low the extent allocator may choose to
60 * allocate an extent from an AG without leaving sufficient space for
61 * a btree split when inserting the new extent. In this case the allocator
62 * will enable the lowspace algorithm which is supposed to allow further
63 * allocations (such as btree splits and newroots) to allocate from
64 * sequential AGs. In order to avoid locking AGs out of order the lowspace
65 * algorithm will start searching for free space from AG 0. If the correct
66 * transaction reservations have been made then this algorithm will eventually
67 * find all the space it needs.
69 typedef struct xfs_bmap_free
71 xfs_bmap_free_item_t
*xbf_first
; /* list of to-be-free extents */
72 int xbf_count
; /* count of items on list */
73 int xbf_low
; /* alloc in low mode */
76 #define XFS_BMAP_MAX_NMAP 4
81 #define XFS_BMAPI_WRITE 0x001 /* write operation: allocate space */
82 #define XFS_BMAPI_DELAY 0x002 /* delayed write operation */
83 #define XFS_BMAPI_ENTIRE 0x004 /* return entire extent, not trimmed */
84 #define XFS_BMAPI_METADATA 0x008 /* mapping metadata not user data */
85 #define XFS_BMAPI_EXACT 0x010 /* allocate only to spec'd bounds */
86 #define XFS_BMAPI_ATTRFORK 0x020 /* use attribute fork not data */
87 #define XFS_BMAPI_ASYNC 0x040 /* bunmapi xactions can be async */
88 #define XFS_BMAPI_RSVBLOCKS 0x080 /* OK to alloc. reserved data blocks */
89 #define XFS_BMAPI_PREALLOC 0x100 /* preallocation op: unwritten space */
90 #define XFS_BMAPI_IGSTATE 0x200 /* Ignore state - */
91 /* combine contig. space */
92 #define XFS_BMAPI_CONTIG 0x400 /* must allocate only one extent */
93 /* XFS_BMAPI_DIRECT_IO 0x800 */
94 #define XFS_BMAPI_CONVERT 0x1000 /* unwritten extent conversion - */
95 /* need write cache flushing and no */
96 /* additional allocation alignments */
98 static inline int xfs_bmapi_aflag(int w
)
100 return (w
== XFS_ATTR_FORK
? XFS_BMAPI_ATTRFORK
: 0);
104 * Special values for xfs_bmbt_irec_t br_startblock field.
106 #define DELAYSTARTBLOCK ((xfs_fsblock_t)-1LL)
107 #define HOLESTARTBLOCK ((xfs_fsblock_t)-2LL)
109 static inline void xfs_bmap_init(xfs_bmap_free_t
*flp
, xfs_fsblock_t
*fbp
)
111 ((flp
)->xbf_first
= NULL
, (flp
)->xbf_count
= 0, \
112 (flp
)->xbf_low
= 0, *(fbp
) = NULLFSBLOCK
);
116 * Argument structure for xfs_bmap_alloc.
118 typedef struct xfs_bmalloca
{
119 xfs_fsblock_t firstblock
; /* i/o first block allocated */
120 xfs_fsblock_t rval
; /* starting block of new extent */
121 xfs_fileoff_t off
; /* offset in file filling in */
122 struct xfs_trans
*tp
; /* transaction pointer */
123 struct xfs_inode
*ip
; /* incore inode pointer */
124 struct xfs_bmbt_irec
*prevp
; /* extent before the new one */
125 struct xfs_bmbt_irec
*gotp
; /* extent after, or delayed */
126 xfs_extlen_t alen
; /* i/o length asked/allocated */
127 xfs_extlen_t total
; /* total blocks needed for xaction */
128 xfs_extlen_t minlen
; /* minimum allocation size (blocks) */
129 xfs_extlen_t minleft
; /* amount must be left after alloc */
130 char eof
; /* set if allocating past last extent */
131 char wasdel
; /* replacing a delayed allocation */
132 char userdata
;/* set if is user data */
133 char low
; /* low on space, using seq'l ags */
134 char aeof
; /* allocated space at eof */
135 char conv
; /* overwriting unwritten extents */
139 * Flags for xfs_bmap_add_extent*.
141 #define BMAP_LEFT_CONTIG (1 << 0)
142 #define BMAP_RIGHT_CONTIG (1 << 1)
143 #define BMAP_LEFT_FILLING (1 << 2)
144 #define BMAP_RIGHT_FILLING (1 << 3)
145 #define BMAP_LEFT_DELAY (1 << 4)
146 #define BMAP_RIGHT_DELAY (1 << 5)
147 #define BMAP_LEFT_VALID (1 << 6)
148 #define BMAP_RIGHT_VALID (1 << 7)
149 #define BMAP_ATTRFORK (1 << 8)
151 #if defined(__KERNEL__) && defined(XFS_BMAP_TRACE)
153 * Trace operations for bmap extent tracing
155 #define XFS_BMAP_KTRACE_DELETE 1
156 #define XFS_BMAP_KTRACE_INSERT 2
157 #define XFS_BMAP_KTRACE_PRE_UP 3
158 #define XFS_BMAP_KTRACE_POST_UP 4
160 #define XFS_BMAP_TRACE_SIZE 4096 /* size of global trace buffer */
161 #define XFS_BMAP_KTRACE_SIZE 32 /* size of per-inode trace buffer */
162 extern ktrace_t
*xfs_bmap_trace_buf
;
165 * Add bmap trace insert entries for all the contents of the extent list.
168 xfs_bmap_trace_exlist(
169 const char *fname
, /* function name */
170 struct xfs_inode
*ip
, /* incore inode pointer */
171 xfs_extnum_t cnt
, /* count of entries in list */
172 int whichfork
); /* data or attr fork */
173 #define XFS_BMAP_TRACE_EXLIST(ip,c,w) \
174 xfs_bmap_trace_exlist(__func__,ip,c,w)
176 #else /* __KERNEL__ && XFS_BMAP_TRACE */
178 #define XFS_BMAP_TRACE_EXLIST(ip,c,w)
180 #endif /* __KERNEL__ && XFS_BMAP_TRACE */
183 * Convert inode from non-attributed to attributed.
184 * Must not be in a transaction, ip must not be locked.
187 xfs_bmap_add_attrfork(
188 struct xfs_inode
*ip
, /* incore inode pointer */
189 int size
, /* space needed for new attribute */
190 int rsvd
); /* flag for reserved block allocation */
193 * Add the extent to the list of extents to be free at transaction end.
194 * The list is maintained sorted (by block number).
198 xfs_fsblock_t bno
, /* fs block number of extent */
199 xfs_filblks_t len
, /* length of extent */
200 xfs_bmap_free_t
*flist
, /* list of extents */
201 struct xfs_mount
*mp
); /* mount point structure */
204 * Routine to clean up the free list data structure when
205 * an error occurs during a transaction.
209 xfs_bmap_free_t
*flist
); /* free list to clean up */
212 * Compute and fill in the value of the maximum depth of a bmap btree
213 * in this filesystem. Done once, during mount.
216 xfs_bmap_compute_maxlevels(
217 struct xfs_mount
*mp
, /* file system mount structure */
218 int whichfork
); /* data or attr fork */
221 * Returns the file-relative block number of the first unused block in the file.
222 * This is the lowest-address hole if the file has holes, else the first block
223 * past the end of file.
226 xfs_bmap_first_unused(
227 struct xfs_trans
*tp
, /* transaction pointer */
228 struct xfs_inode
*ip
, /* incore inode */
229 xfs_extlen_t len
, /* size of hole to find */
230 xfs_fileoff_t
*unused
, /* unused block num */
231 int whichfork
); /* data or attr fork */
234 * Returns the file-relative block number of the last block + 1 before
235 * last_block (input value) in the file.
236 * This is not based on i_size, it is based on the extent list.
237 * Returns 0 for local files, as they do not have an extent list.
240 xfs_bmap_last_before(
241 struct xfs_trans
*tp
, /* transaction pointer */
242 struct xfs_inode
*ip
, /* incore inode */
243 xfs_fileoff_t
*last_block
, /* last block */
244 int whichfork
); /* data or attr fork */
247 * Returns the file-relative block number of the first block past eof in
248 * the file. This is not based on i_size, it is based on the extent list.
249 * Returns 0 for local files, as they do not have an extent list.
252 xfs_bmap_last_offset(
253 struct xfs_trans
*tp
, /* transaction pointer */
254 struct xfs_inode
*ip
, /* incore inode */
255 xfs_fileoff_t
*unused
, /* last block num */
256 int whichfork
); /* data or attr fork */
259 * Returns whether the selected fork of the inode has exactly one
260 * block or not. For the data fork we check this matches di_size,
261 * implying the file's range is 0..bsize-1.
265 struct xfs_inode
*ip
, /* incore inode */
266 int whichfork
); /* data or attr fork */
269 * Read in the extents to iu_extents.
270 * All inode fields are set up by caller, we just traverse the btree
271 * and copy the records in.
274 xfs_bmap_read_extents(
275 struct xfs_trans
*tp
, /* transaction pointer */
276 struct xfs_inode
*ip
, /* incore inode */
277 int whichfork
); /* data or attr fork */
280 * Map file blocks to filesystem blocks.
281 * File range is given by the bno/len pair.
282 * Adds blocks to file if a write ("flags & XFS_BMAPI_WRITE" set)
283 * into a hole or past eof.
284 * Only allocates blocks from a single allocation group,
285 * to avoid locking problems.
286 * The returned value in "firstblock" from the first call in a transaction
287 * must be remembered and presented to subsequent calls in "firstblock".
288 * An upper bound for the number of blocks to be allocated is supplied to
289 * the first call in "total"; if no allocation group has that many free
290 * blocks then the call will fail (return NULLFSBLOCK in "firstblock").
294 struct xfs_trans
*tp
, /* transaction pointer */
295 struct xfs_inode
*ip
, /* incore inode */
296 xfs_fileoff_t bno
, /* starting file offs. mapped */
297 xfs_filblks_t len
, /* length to map in file */
298 int flags
, /* XFS_BMAPI_... */
299 xfs_fsblock_t
*firstblock
, /* first allocated block
300 controls a.g. for allocs */
301 xfs_extlen_t total
, /* total blocks needed */
302 struct xfs_bmbt_irec
*mval
, /* output: map values */
303 int *nmap
, /* i/o: mval size/count */
304 xfs_bmap_free_t
*flist
, /* i/o: list extents to free */
305 xfs_extdelta_t
*delta
); /* o: change made to incore
309 * Map file blocks to filesystem blocks, simple version.
310 * One block only, read-only.
311 * For flags, only the XFS_BMAPI_ATTRFORK flag is examined.
312 * For the other flag values, the effect is as if XFS_BMAPI_METADATA
313 * was set and all the others were clear.
317 struct xfs_trans
*tp
, /* transaction pointer */
318 struct xfs_inode
*ip
, /* incore inode */
319 int whichfork
, /* data or attr fork */
320 xfs_fsblock_t
*fsb
, /* output: mapped block */
321 xfs_fileoff_t bno
); /* starting file offs. mapped */
324 * Unmap (remove) blocks from a file.
325 * If nexts is nonzero then the number of extents to remove is limited to
326 * that value. If not all extents in the block range can be removed then
331 struct xfs_trans
*tp
, /* transaction pointer */
332 struct xfs_inode
*ip
, /* incore inode */
333 xfs_fileoff_t bno
, /* starting offset to unmap */
334 xfs_filblks_t len
, /* length to unmap in file */
335 int flags
, /* XFS_BMAPI_... */
336 xfs_extnum_t nexts
, /* number of extents max */
337 xfs_fsblock_t
*firstblock
, /* first allocated block
338 controls a.g. for allocs */
339 xfs_bmap_free_t
*flist
, /* i/o: list extents to free */
340 xfs_extdelta_t
*delta
, /* o: change made to incore
342 int *done
); /* set if not done yet */
345 * Check an extent list, which has just been read, for
346 * any bit in the extent flag field.
349 xfs_check_nostate_extents(
350 struct xfs_ifork
*ifp
,
355 xfs_default_attroffset(
356 struct xfs_inode
*ip
);
361 * Routine to be called at transaction's end by xfs_bmapi, xfs_bunmapi
362 * caller. Frees all the extents that need freeing, which must be done
363 * last due to locking considerations.
365 * Return 1 if the given transaction was committed and a new one allocated,
370 struct xfs_trans
**tp
, /* transaction pointer addr */
371 xfs_bmap_free_t
*flist
, /* i/o: list extents to free */
372 int *committed
); /* xact committed or not */
374 /* bmap to userspace formatter - copy to user & advance pointer */
375 typedef int (*xfs_bmap_format_t
)(void **, struct getbmapx
*, int *);
378 * Get inode's extents as described in bmv, and format for output.
383 struct getbmapx
*bmv
, /* user bmap structure */
384 xfs_bmap_format_t formatter
, /* format to user */
385 void *arg
); /* formatter arg */
388 * Check if the endoff is outside the last extent. If so the caller will grow
389 * the allocation to a stripe unit boundary
393 struct xfs_inode
*ip
,
394 xfs_fileoff_t endoff
,
399 * Count fsblocks of the given fork.
402 xfs_bmap_count_blocks(
404 struct xfs_inode
*ip
,
408 #endif /* __KERNEL__ */
410 #endif /* __XFS_BMAP_H__ */