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