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 #include <linux/log2.h> 19 20 #include "xfs.h" 21 #include "xfs_fs.h" 22 #include "xfs_format.h" 23 #include "xfs_log_format.h" 24 #include "xfs_trans_resv.h" 25 #include "xfs_mount.h" 26 #include "xfs_inode.h" 27 #include "xfs_trans.h" 28 #include "xfs_inode_item.h" 29 #include "xfs_bmap_btree.h" 30 #include "xfs_bmap.h" 31 #include "xfs_error.h" 32 #include "xfs_trace.h" 33 #include "xfs_attr_sf.h" 34 #include "xfs_da_format.h" 35 36 kmem_zone_t *xfs_ifork_zone; 37 38 STATIC int xfs_iformat_local(xfs_inode_t *, xfs_dinode_t *, int, int); 39 STATIC int xfs_iformat_extents(xfs_inode_t *, xfs_dinode_t *, int); 40 STATIC int xfs_iformat_btree(xfs_inode_t *, xfs_dinode_t *, int); 41 42 #ifdef DEBUG 43 /* 44 * Make sure that the extents in the given memory buffer 45 * are valid. 46 */ 47 void 48 xfs_validate_extents( 49 xfs_ifork_t *ifp, 50 int nrecs, 51 xfs_exntfmt_t fmt) 52 { 53 xfs_bmbt_irec_t irec; 54 xfs_bmbt_rec_host_t rec; 55 int i; 56 57 for (i = 0; i < nrecs; i++) { 58 xfs_bmbt_rec_host_t *ep = xfs_iext_get_ext(ifp, i); 59 rec.l0 = get_unaligned(&ep->l0); 60 rec.l1 = get_unaligned(&ep->l1); 61 xfs_bmbt_get_all(&rec, &irec); 62 if (fmt == XFS_EXTFMT_NOSTATE) 63 ASSERT(irec.br_state == XFS_EXT_NORM); 64 } 65 } 66 #else /* DEBUG */ 67 #define xfs_validate_extents(ifp, nrecs, fmt) 68 #endif /* DEBUG */ 69 70 71 /* 72 * Move inode type and inode format specific information from the 73 * on-disk inode to the in-core inode. For fifos, devs, and sockets 74 * this means set if_rdev to the proper value. For files, directories, 75 * and symlinks this means to bring in the in-line data or extent 76 * pointers. For a file in B-tree format, only the root is immediately 77 * brought in-core. The rest will be in-lined in if_extents when it 78 * is first referenced (see xfs_iread_extents()). 79 */ 80 int 81 xfs_iformat_fork( 82 xfs_inode_t *ip, 83 xfs_dinode_t *dip) 84 { 85 xfs_attr_shortform_t *atp; 86 int size; 87 int error = 0; 88 xfs_fsize_t di_size; 89 90 if (unlikely(be32_to_cpu(dip->di_nextents) + 91 be16_to_cpu(dip->di_anextents) > 92 be64_to_cpu(dip->di_nblocks))) { 93 xfs_warn(ip->i_mount, 94 "corrupt dinode %Lu, extent total = %d, nblocks = %Lu.", 95 (unsigned long long)ip->i_ino, 96 (int)(be32_to_cpu(dip->di_nextents) + 97 be16_to_cpu(dip->di_anextents)), 98 (unsigned long long) 99 be64_to_cpu(dip->di_nblocks)); 100 XFS_CORRUPTION_ERROR("xfs_iformat(1)", XFS_ERRLEVEL_LOW, 101 ip->i_mount, dip); 102 return -EFSCORRUPTED; 103 } 104 105 if (unlikely(dip->di_forkoff > ip->i_mount->m_sb.sb_inodesize)) { 106 xfs_warn(ip->i_mount, "corrupt dinode %Lu, forkoff = 0x%x.", 107 (unsigned long long)ip->i_ino, 108 dip->di_forkoff); 109 XFS_CORRUPTION_ERROR("xfs_iformat(2)", XFS_ERRLEVEL_LOW, 110 ip->i_mount, dip); 111 return -EFSCORRUPTED; 112 } 113 114 if (unlikely((ip->i_d.di_flags & XFS_DIFLAG_REALTIME) && 115 !ip->i_mount->m_rtdev_targp)) { 116 xfs_warn(ip->i_mount, 117 "corrupt dinode %Lu, has realtime flag set.", 118 ip->i_ino); 119 XFS_CORRUPTION_ERROR("xfs_iformat(realtime)", 120 XFS_ERRLEVEL_LOW, ip->i_mount, dip); 121 return -EFSCORRUPTED; 122 } 123 124 switch (VFS_I(ip)->i_mode & S_IFMT) { 125 case S_IFIFO: 126 case S_IFCHR: 127 case S_IFBLK: 128 case S_IFSOCK: 129 if (unlikely(dip->di_format != XFS_DINODE_FMT_DEV)) { 130 XFS_CORRUPTION_ERROR("xfs_iformat(3)", XFS_ERRLEVEL_LOW, 131 ip->i_mount, dip); 132 return -EFSCORRUPTED; 133 } 134 ip->i_d.di_size = 0; 135 ip->i_df.if_u2.if_rdev = xfs_dinode_get_rdev(dip); 136 break; 137 138 case S_IFREG: 139 case S_IFLNK: 140 case S_IFDIR: 141 switch (dip->di_format) { 142 case XFS_DINODE_FMT_LOCAL: 143 /* 144 * no local regular files yet 145 */ 146 if (unlikely(S_ISREG(be16_to_cpu(dip->di_mode)))) { 147 xfs_warn(ip->i_mount, 148 "corrupt inode %Lu (local format for regular file).", 149 (unsigned long long) ip->i_ino); 150 XFS_CORRUPTION_ERROR("xfs_iformat(4)", 151 XFS_ERRLEVEL_LOW, 152 ip->i_mount, dip); 153 return -EFSCORRUPTED; 154 } 155 156 di_size = be64_to_cpu(dip->di_size); 157 if (unlikely(di_size < 0 || 158 di_size > XFS_DFORK_DSIZE(dip, ip->i_mount))) { 159 xfs_warn(ip->i_mount, 160 "corrupt inode %Lu (bad size %Ld for local inode).", 161 (unsigned long long) ip->i_ino, 162 (long long) di_size); 163 XFS_CORRUPTION_ERROR("xfs_iformat(5)", 164 XFS_ERRLEVEL_LOW, 165 ip->i_mount, dip); 166 return -EFSCORRUPTED; 167 } 168 169 size = (int)di_size; 170 error = xfs_iformat_local(ip, dip, XFS_DATA_FORK, size); 171 break; 172 case XFS_DINODE_FMT_EXTENTS: 173 error = xfs_iformat_extents(ip, dip, XFS_DATA_FORK); 174 break; 175 case XFS_DINODE_FMT_BTREE: 176 error = xfs_iformat_btree(ip, dip, XFS_DATA_FORK); 177 break; 178 default: 179 XFS_ERROR_REPORT("xfs_iformat(6)", XFS_ERRLEVEL_LOW, 180 ip->i_mount); 181 return -EFSCORRUPTED; 182 } 183 break; 184 185 default: 186 XFS_ERROR_REPORT("xfs_iformat(7)", XFS_ERRLEVEL_LOW, ip->i_mount); 187 return -EFSCORRUPTED; 188 } 189 if (error) { 190 return error; 191 } 192 if (!XFS_DFORK_Q(dip)) 193 return 0; 194 195 ASSERT(ip->i_afp == NULL); 196 ip->i_afp = kmem_zone_zalloc(xfs_ifork_zone, KM_SLEEP | KM_NOFS); 197 198 switch (dip->di_aformat) { 199 case XFS_DINODE_FMT_LOCAL: 200 atp = (xfs_attr_shortform_t *)XFS_DFORK_APTR(dip); 201 size = be16_to_cpu(atp->hdr.totsize); 202 203 if (unlikely(size < sizeof(struct xfs_attr_sf_hdr))) { 204 xfs_warn(ip->i_mount, 205 "corrupt inode %Lu (bad attr fork size %Ld).", 206 (unsigned long long) ip->i_ino, 207 (long long) size); 208 XFS_CORRUPTION_ERROR("xfs_iformat(8)", 209 XFS_ERRLEVEL_LOW, 210 ip->i_mount, dip); 211 return -EFSCORRUPTED; 212 } 213 214 error = xfs_iformat_local(ip, dip, XFS_ATTR_FORK, size); 215 break; 216 case XFS_DINODE_FMT_EXTENTS: 217 error = xfs_iformat_extents(ip, dip, XFS_ATTR_FORK); 218 break; 219 case XFS_DINODE_FMT_BTREE: 220 error = xfs_iformat_btree(ip, dip, XFS_ATTR_FORK); 221 break; 222 default: 223 error = -EFSCORRUPTED; 224 break; 225 } 226 if (error) { 227 kmem_zone_free(xfs_ifork_zone, ip->i_afp); 228 ip->i_afp = NULL; 229 xfs_idestroy_fork(ip, XFS_DATA_FORK); 230 } 231 return error; 232 } 233 234 void 235 xfs_init_local_fork( 236 struct xfs_inode *ip, 237 int whichfork, 238 const void *data, 239 int size) 240 { 241 struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, whichfork); 242 int mem_size = size, real_size = 0; 243 bool zero_terminate; 244 245 /* 246 * If we are using the local fork to store a symlink body we need to 247 * zero-terminate it so that we can pass it back to the VFS directly. 248 * Overallocate the in-memory fork by one for that and add a zero 249 * to terminate it below. 250 */ 251 zero_terminate = S_ISLNK(VFS_I(ip)->i_mode); 252 if (zero_terminate) 253 mem_size++; 254 255 if (size == 0) 256 ifp->if_u1.if_data = NULL; 257 else if (mem_size <= sizeof(ifp->if_u2.if_inline_data)) 258 ifp->if_u1.if_data = ifp->if_u2.if_inline_data; 259 else { 260 real_size = roundup(mem_size, 4); 261 ifp->if_u1.if_data = kmem_alloc(real_size, KM_SLEEP | KM_NOFS); 262 } 263 264 if (size) { 265 memcpy(ifp->if_u1.if_data, data, size); 266 if (zero_terminate) 267 ifp->if_u1.if_data[size] = '\0'; 268 } 269 270 ifp->if_bytes = size; 271 ifp->if_real_bytes = real_size; 272 ifp->if_flags &= ~(XFS_IFEXTENTS | XFS_IFBROOT); 273 ifp->if_flags |= XFS_IFINLINE; 274 } 275 276 /* 277 * The file is in-lined in the on-disk inode. 278 * If it fits into if_inline_data, then copy 279 * it there, otherwise allocate a buffer for it 280 * and copy the data there. Either way, set 281 * if_data to point at the data. 282 * If we allocate a buffer for the data, make 283 * sure that its size is a multiple of 4 and 284 * record the real size in i_real_bytes. 285 */ 286 STATIC int 287 xfs_iformat_local( 288 xfs_inode_t *ip, 289 xfs_dinode_t *dip, 290 int whichfork, 291 int size) 292 { 293 294 /* 295 * If the size is unreasonable, then something 296 * is wrong and we just bail out rather than crash in 297 * kmem_alloc() or memcpy() below. 298 */ 299 if (unlikely(size > XFS_DFORK_SIZE(dip, ip->i_mount, whichfork))) { 300 xfs_warn(ip->i_mount, 301 "corrupt inode %Lu (bad size %d for local fork, size = %d).", 302 (unsigned long long) ip->i_ino, size, 303 XFS_DFORK_SIZE(dip, ip->i_mount, whichfork)); 304 XFS_CORRUPTION_ERROR("xfs_iformat_local", XFS_ERRLEVEL_LOW, 305 ip->i_mount, dip); 306 return -EFSCORRUPTED; 307 } 308 309 xfs_init_local_fork(ip, whichfork, XFS_DFORK_PTR(dip, whichfork), size); 310 return 0; 311 } 312 313 /* 314 * The file consists of a set of extents all 315 * of which fit into the on-disk inode. 316 * If there are few enough extents to fit into 317 * the if_inline_ext, then copy them there. 318 * Otherwise allocate a buffer for them and copy 319 * them into it. Either way, set if_extents 320 * to point at the extents. 321 */ 322 STATIC int 323 xfs_iformat_extents( 324 xfs_inode_t *ip, 325 xfs_dinode_t *dip, 326 int whichfork) 327 { 328 xfs_bmbt_rec_t *dp; 329 xfs_ifork_t *ifp; 330 int nex; 331 int size; 332 int i; 333 334 ifp = XFS_IFORK_PTR(ip, whichfork); 335 nex = XFS_DFORK_NEXTENTS(dip, whichfork); 336 size = nex * (uint)sizeof(xfs_bmbt_rec_t); 337 338 /* 339 * If the number of extents is unreasonable, then something 340 * is wrong and we just bail out rather than crash in 341 * kmem_alloc() or memcpy() below. 342 */ 343 if (unlikely(size < 0 || size > XFS_DFORK_SIZE(dip, ip->i_mount, whichfork))) { 344 xfs_warn(ip->i_mount, "corrupt inode %Lu ((a)extents = %d).", 345 (unsigned long long) ip->i_ino, nex); 346 XFS_CORRUPTION_ERROR("xfs_iformat_extents(1)", XFS_ERRLEVEL_LOW, 347 ip->i_mount, dip); 348 return -EFSCORRUPTED; 349 } 350 351 ifp->if_real_bytes = 0; 352 if (nex == 0) 353 ifp->if_u1.if_extents = NULL; 354 else if (nex <= XFS_INLINE_EXTS) 355 ifp->if_u1.if_extents = ifp->if_u2.if_inline_ext; 356 else 357 xfs_iext_add(ifp, 0, nex); 358 359 ifp->if_bytes = size; 360 if (size) { 361 dp = (xfs_bmbt_rec_t *) XFS_DFORK_PTR(dip, whichfork); 362 xfs_validate_extents(ifp, nex, XFS_EXTFMT_INODE(ip)); 363 for (i = 0; i < nex; i++, dp++) { 364 xfs_bmbt_rec_host_t *ep = xfs_iext_get_ext(ifp, i); 365 ep->l0 = get_unaligned_be64(&dp->l0); 366 ep->l1 = get_unaligned_be64(&dp->l1); 367 } 368 XFS_BMAP_TRACE_EXLIST(ip, nex, whichfork); 369 if (whichfork != XFS_DATA_FORK || 370 XFS_EXTFMT_INODE(ip) == XFS_EXTFMT_NOSTATE) 371 if (unlikely(xfs_check_nostate_extents( 372 ifp, 0, nex))) { 373 XFS_ERROR_REPORT("xfs_iformat_extents(2)", 374 XFS_ERRLEVEL_LOW, 375 ip->i_mount); 376 return -EFSCORRUPTED; 377 } 378 } 379 ifp->if_flags |= XFS_IFEXTENTS; 380 return 0; 381 } 382 383 /* 384 * The file has too many extents to fit into 385 * the inode, so they are in B-tree format. 386 * Allocate a buffer for the root of the B-tree 387 * and copy the root into it. The i_extents 388 * field will remain NULL until all of the 389 * extents are read in (when they are needed). 390 */ 391 STATIC int 392 xfs_iformat_btree( 393 xfs_inode_t *ip, 394 xfs_dinode_t *dip, 395 int whichfork) 396 { 397 struct xfs_mount *mp = ip->i_mount; 398 xfs_bmdr_block_t *dfp; 399 xfs_ifork_t *ifp; 400 /* REFERENCED */ 401 int nrecs; 402 int size; 403 404 ifp = XFS_IFORK_PTR(ip, whichfork); 405 dfp = (xfs_bmdr_block_t *)XFS_DFORK_PTR(dip, whichfork); 406 size = XFS_BMAP_BROOT_SPACE(mp, dfp); 407 nrecs = be16_to_cpu(dfp->bb_numrecs); 408 409 /* 410 * blow out if -- fork has less extents than can fit in 411 * fork (fork shouldn't be a btree format), root btree 412 * block has more records than can fit into the fork, 413 * or the number of extents is greater than the number of 414 * blocks. 415 */ 416 if (unlikely(XFS_IFORK_NEXTENTS(ip, whichfork) <= 417 XFS_IFORK_MAXEXT(ip, whichfork) || 418 XFS_BMDR_SPACE_CALC(nrecs) > 419 XFS_DFORK_SIZE(dip, mp, whichfork) || 420 XFS_IFORK_NEXTENTS(ip, whichfork) > ip->i_d.di_nblocks)) { 421 xfs_warn(mp, "corrupt inode %Lu (btree).", 422 (unsigned long long) ip->i_ino); 423 XFS_CORRUPTION_ERROR("xfs_iformat_btree", XFS_ERRLEVEL_LOW, 424 mp, dip); 425 return -EFSCORRUPTED; 426 } 427 428 ifp->if_broot_bytes = size; 429 ifp->if_broot = kmem_alloc(size, KM_SLEEP | KM_NOFS); 430 ASSERT(ifp->if_broot != NULL); 431 /* 432 * Copy and convert from the on-disk structure 433 * to the in-memory structure. 434 */ 435 xfs_bmdr_to_bmbt(ip, dfp, XFS_DFORK_SIZE(dip, ip->i_mount, whichfork), 436 ifp->if_broot, size); 437 ifp->if_flags &= ~XFS_IFEXTENTS; 438 ifp->if_flags |= XFS_IFBROOT; 439 440 return 0; 441 } 442 443 /* 444 * Read in extents from a btree-format inode. 445 * Allocate and fill in if_extents. Real work is done in xfs_bmap.c. 446 */ 447 int 448 xfs_iread_extents( 449 xfs_trans_t *tp, 450 xfs_inode_t *ip, 451 int whichfork) 452 { 453 int error; 454 xfs_ifork_t *ifp; 455 xfs_extnum_t nextents; 456 457 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL)); 458 459 if (unlikely(XFS_IFORK_FORMAT(ip, whichfork) != XFS_DINODE_FMT_BTREE)) { 460 XFS_ERROR_REPORT("xfs_iread_extents", XFS_ERRLEVEL_LOW, 461 ip->i_mount); 462 return -EFSCORRUPTED; 463 } 464 nextents = XFS_IFORK_NEXTENTS(ip, whichfork); 465 ifp = XFS_IFORK_PTR(ip, whichfork); 466 467 /* 468 * We know that the size is valid (it's checked in iformat_btree) 469 */ 470 ifp->if_bytes = ifp->if_real_bytes = 0; 471 ifp->if_flags |= XFS_IFEXTENTS; 472 xfs_iext_add(ifp, 0, nextents); 473 error = xfs_bmap_read_extents(tp, ip, whichfork); 474 if (error) { 475 xfs_iext_destroy(ifp); 476 ifp->if_flags &= ~XFS_IFEXTENTS; 477 return error; 478 } 479 xfs_validate_extents(ifp, nextents, XFS_EXTFMT_INODE(ip)); 480 return 0; 481 } 482 /* 483 * Reallocate the space for if_broot based on the number of records 484 * being added or deleted as indicated in rec_diff. Move the records 485 * and pointers in if_broot to fit the new size. When shrinking this 486 * will eliminate holes between the records and pointers created by 487 * the caller. When growing this will create holes to be filled in 488 * by the caller. 489 * 490 * The caller must not request to add more records than would fit in 491 * the on-disk inode root. If the if_broot is currently NULL, then 492 * if we are adding records, one will be allocated. The caller must also 493 * not request that the number of records go below zero, although 494 * it can go to zero. 495 * 496 * ip -- the inode whose if_broot area is changing 497 * ext_diff -- the change in the number of records, positive or negative, 498 * requested for the if_broot array. 499 */ 500 void 501 xfs_iroot_realloc( 502 xfs_inode_t *ip, 503 int rec_diff, 504 int whichfork) 505 { 506 struct xfs_mount *mp = ip->i_mount; 507 int cur_max; 508 xfs_ifork_t *ifp; 509 struct xfs_btree_block *new_broot; 510 int new_max; 511 size_t new_size; 512 char *np; 513 char *op; 514 515 /* 516 * Handle the degenerate case quietly. 517 */ 518 if (rec_diff == 0) { 519 return; 520 } 521 522 ifp = XFS_IFORK_PTR(ip, whichfork); 523 if (rec_diff > 0) { 524 /* 525 * If there wasn't any memory allocated before, just 526 * allocate it now and get out. 527 */ 528 if (ifp->if_broot_bytes == 0) { 529 new_size = XFS_BMAP_BROOT_SPACE_CALC(mp, rec_diff); 530 ifp->if_broot = kmem_alloc(new_size, KM_SLEEP | KM_NOFS); 531 ifp->if_broot_bytes = (int)new_size; 532 return; 533 } 534 535 /* 536 * If there is already an existing if_broot, then we need 537 * to realloc() it and shift the pointers to their new 538 * location. The records don't change location because 539 * they are kept butted up against the btree block header. 540 */ 541 cur_max = xfs_bmbt_maxrecs(mp, ifp->if_broot_bytes, 0); 542 new_max = cur_max + rec_diff; 543 new_size = XFS_BMAP_BROOT_SPACE_CALC(mp, new_max); 544 ifp->if_broot = kmem_realloc(ifp->if_broot, new_size, 545 KM_SLEEP | KM_NOFS); 546 op = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, ifp->if_broot, 1, 547 ifp->if_broot_bytes); 548 np = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, ifp->if_broot, 1, 549 (int)new_size); 550 ifp->if_broot_bytes = (int)new_size; 551 ASSERT(XFS_BMAP_BMDR_SPACE(ifp->if_broot) <= 552 XFS_IFORK_SIZE(ip, whichfork)); 553 memmove(np, op, cur_max * (uint)sizeof(xfs_fsblock_t)); 554 return; 555 } 556 557 /* 558 * rec_diff is less than 0. In this case, we are shrinking the 559 * if_broot buffer. It must already exist. If we go to zero 560 * records, just get rid of the root and clear the status bit. 561 */ 562 ASSERT((ifp->if_broot != NULL) && (ifp->if_broot_bytes > 0)); 563 cur_max = xfs_bmbt_maxrecs(mp, ifp->if_broot_bytes, 0); 564 new_max = cur_max + rec_diff; 565 ASSERT(new_max >= 0); 566 if (new_max > 0) 567 new_size = XFS_BMAP_BROOT_SPACE_CALC(mp, new_max); 568 else 569 new_size = 0; 570 if (new_size > 0) { 571 new_broot = kmem_alloc(new_size, KM_SLEEP | KM_NOFS); 572 /* 573 * First copy over the btree block header. 574 */ 575 memcpy(new_broot, ifp->if_broot, 576 XFS_BMBT_BLOCK_LEN(ip->i_mount)); 577 } else { 578 new_broot = NULL; 579 ifp->if_flags &= ~XFS_IFBROOT; 580 } 581 582 /* 583 * Only copy the records and pointers if there are any. 584 */ 585 if (new_max > 0) { 586 /* 587 * First copy the records. 588 */ 589 op = (char *)XFS_BMBT_REC_ADDR(mp, ifp->if_broot, 1); 590 np = (char *)XFS_BMBT_REC_ADDR(mp, new_broot, 1); 591 memcpy(np, op, new_max * (uint)sizeof(xfs_bmbt_rec_t)); 592 593 /* 594 * Then copy the pointers. 595 */ 596 op = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, ifp->if_broot, 1, 597 ifp->if_broot_bytes); 598 np = (char *)XFS_BMAP_BROOT_PTR_ADDR(mp, new_broot, 1, 599 (int)new_size); 600 memcpy(np, op, new_max * (uint)sizeof(xfs_fsblock_t)); 601 } 602 kmem_free(ifp->if_broot); 603 ifp->if_broot = new_broot; 604 ifp->if_broot_bytes = (int)new_size; 605 if (ifp->if_broot) 606 ASSERT(XFS_BMAP_BMDR_SPACE(ifp->if_broot) <= 607 XFS_IFORK_SIZE(ip, whichfork)); 608 return; 609 } 610 611 612 /* 613 * This is called when the amount of space needed for if_data 614 * is increased or decreased. The change in size is indicated by 615 * the number of bytes that need to be added or deleted in the 616 * byte_diff parameter. 617 * 618 * If the amount of space needed has decreased below the size of the 619 * inline buffer, then switch to using the inline buffer. Otherwise, 620 * use kmem_realloc() or kmem_alloc() to adjust the size of the buffer 621 * to what is needed. 622 * 623 * ip -- the inode whose if_data area is changing 624 * byte_diff -- the change in the number of bytes, positive or negative, 625 * requested for the if_data array. 626 */ 627 void 628 xfs_idata_realloc( 629 xfs_inode_t *ip, 630 int byte_diff, 631 int whichfork) 632 { 633 xfs_ifork_t *ifp; 634 int new_size; 635 int real_size; 636 637 if (byte_diff == 0) { 638 return; 639 } 640 641 ifp = XFS_IFORK_PTR(ip, whichfork); 642 new_size = (int)ifp->if_bytes + byte_diff; 643 ASSERT(new_size >= 0); 644 645 if (new_size == 0) { 646 if (ifp->if_u1.if_data != ifp->if_u2.if_inline_data) { 647 kmem_free(ifp->if_u1.if_data); 648 } 649 ifp->if_u1.if_data = NULL; 650 real_size = 0; 651 } else if (new_size <= sizeof(ifp->if_u2.if_inline_data)) { 652 /* 653 * If the valid extents/data can fit in if_inline_ext/data, 654 * copy them from the malloc'd vector and free it. 655 */ 656 if (ifp->if_u1.if_data == NULL) { 657 ifp->if_u1.if_data = ifp->if_u2.if_inline_data; 658 } else if (ifp->if_u1.if_data != ifp->if_u2.if_inline_data) { 659 ASSERT(ifp->if_real_bytes != 0); 660 memcpy(ifp->if_u2.if_inline_data, ifp->if_u1.if_data, 661 new_size); 662 kmem_free(ifp->if_u1.if_data); 663 ifp->if_u1.if_data = ifp->if_u2.if_inline_data; 664 } 665 real_size = 0; 666 } else { 667 /* 668 * Stuck with malloc/realloc. 669 * For inline data, the underlying buffer must be 670 * a multiple of 4 bytes in size so that it can be 671 * logged and stay on word boundaries. We enforce 672 * that here. 673 */ 674 real_size = roundup(new_size, 4); 675 if (ifp->if_u1.if_data == NULL) { 676 ASSERT(ifp->if_real_bytes == 0); 677 ifp->if_u1.if_data = kmem_alloc(real_size, 678 KM_SLEEP | KM_NOFS); 679 } else if (ifp->if_u1.if_data != ifp->if_u2.if_inline_data) { 680 /* 681 * Only do the realloc if the underlying size 682 * is really changing. 683 */ 684 if (ifp->if_real_bytes != real_size) { 685 ifp->if_u1.if_data = 686 kmem_realloc(ifp->if_u1.if_data, 687 real_size, 688 KM_SLEEP | KM_NOFS); 689 } 690 } else { 691 ASSERT(ifp->if_real_bytes == 0); 692 ifp->if_u1.if_data = kmem_alloc(real_size, 693 KM_SLEEP | KM_NOFS); 694 memcpy(ifp->if_u1.if_data, ifp->if_u2.if_inline_data, 695 ifp->if_bytes); 696 } 697 } 698 ifp->if_real_bytes = real_size; 699 ifp->if_bytes = new_size; 700 ASSERT(ifp->if_bytes <= XFS_IFORK_SIZE(ip, whichfork)); 701 } 702 703 void 704 xfs_idestroy_fork( 705 xfs_inode_t *ip, 706 int whichfork) 707 { 708 xfs_ifork_t *ifp; 709 710 ifp = XFS_IFORK_PTR(ip, whichfork); 711 if (ifp->if_broot != NULL) { 712 kmem_free(ifp->if_broot); 713 ifp->if_broot = NULL; 714 } 715 716 /* 717 * If the format is local, then we can't have an extents 718 * array so just look for an inline data array. If we're 719 * not local then we may or may not have an extents list, 720 * so check and free it up if we do. 721 */ 722 if (XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_LOCAL) { 723 if ((ifp->if_u1.if_data != ifp->if_u2.if_inline_data) && 724 (ifp->if_u1.if_data != NULL)) { 725 ASSERT(ifp->if_real_bytes != 0); 726 kmem_free(ifp->if_u1.if_data); 727 ifp->if_u1.if_data = NULL; 728 ifp->if_real_bytes = 0; 729 } 730 } else if ((ifp->if_flags & XFS_IFEXTENTS) && 731 ((ifp->if_flags & XFS_IFEXTIREC) || 732 ((ifp->if_u1.if_extents != NULL) && 733 (ifp->if_u1.if_extents != ifp->if_u2.if_inline_ext)))) { 734 ASSERT(ifp->if_real_bytes != 0); 735 xfs_iext_destroy(ifp); 736 } 737 ASSERT(ifp->if_u1.if_extents == NULL || 738 ifp->if_u1.if_extents == ifp->if_u2.if_inline_ext); 739 ASSERT(ifp->if_real_bytes == 0); 740 if (whichfork == XFS_ATTR_FORK) { 741 kmem_zone_free(xfs_ifork_zone, ip->i_afp); 742 ip->i_afp = NULL; 743 } 744 } 745 746 /* 747 * Convert in-core extents to on-disk form 748 * 749 * For either the data or attr fork in extent format, we need to endian convert 750 * the in-core extent as we place them into the on-disk inode. 751 * 752 * In the case of the data fork, the in-core and on-disk fork sizes can be 753 * different due to delayed allocation extents. We only copy on-disk extents 754 * here, so callers must always use the physical fork size to determine the 755 * size of the buffer passed to this routine. We will return the size actually 756 * used. 757 */ 758 int 759 xfs_iextents_copy( 760 xfs_inode_t *ip, 761 xfs_bmbt_rec_t *dp, 762 int whichfork) 763 { 764 int copied; 765 int i; 766 xfs_ifork_t *ifp; 767 int nrecs; 768 xfs_fsblock_t start_block; 769 770 ifp = XFS_IFORK_PTR(ip, whichfork); 771 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)); 772 ASSERT(ifp->if_bytes > 0); 773 774 nrecs = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t); 775 XFS_BMAP_TRACE_EXLIST(ip, nrecs, whichfork); 776 ASSERT(nrecs > 0); 777 778 /* 779 * There are some delayed allocation extents in the 780 * inode, so copy the extents one at a time and skip 781 * the delayed ones. There must be at least one 782 * non-delayed extent. 783 */ 784 copied = 0; 785 for (i = 0; i < nrecs; i++) { 786 xfs_bmbt_rec_host_t *ep = xfs_iext_get_ext(ifp, i); 787 start_block = xfs_bmbt_get_startblock(ep); 788 if (isnullstartblock(start_block)) { 789 /* 790 * It's a delayed allocation extent, so skip it. 791 */ 792 continue; 793 } 794 795 /* Translate to on disk format */ 796 put_unaligned_be64(ep->l0, &dp->l0); 797 put_unaligned_be64(ep->l1, &dp->l1); 798 dp++; 799 copied++; 800 } 801 ASSERT(copied != 0); 802 xfs_validate_extents(ifp, copied, XFS_EXTFMT_INODE(ip)); 803 804 return (copied * (uint)sizeof(xfs_bmbt_rec_t)); 805 } 806 807 /* 808 * Each of the following cases stores data into the same region 809 * of the on-disk inode, so only one of them can be valid at 810 * any given time. While it is possible to have conflicting formats 811 * and log flags, e.g. having XFS_ILOG_?DATA set when the fork is 812 * in EXTENTS format, this can only happen when the fork has 813 * changed formats after being modified but before being flushed. 814 * In these cases, the format always takes precedence, because the 815 * format indicates the current state of the fork. 816 */ 817 void 818 xfs_iflush_fork( 819 xfs_inode_t *ip, 820 xfs_dinode_t *dip, 821 xfs_inode_log_item_t *iip, 822 int whichfork) 823 { 824 char *cp; 825 xfs_ifork_t *ifp; 826 xfs_mount_t *mp; 827 static const short brootflag[2] = 828 { XFS_ILOG_DBROOT, XFS_ILOG_ABROOT }; 829 static const short dataflag[2] = 830 { XFS_ILOG_DDATA, XFS_ILOG_ADATA }; 831 static const short extflag[2] = 832 { XFS_ILOG_DEXT, XFS_ILOG_AEXT }; 833 834 if (!iip) 835 return; 836 ifp = XFS_IFORK_PTR(ip, whichfork); 837 /* 838 * This can happen if we gave up in iformat in an error path, 839 * for the attribute fork. 840 */ 841 if (!ifp) { 842 ASSERT(whichfork == XFS_ATTR_FORK); 843 return; 844 } 845 cp = XFS_DFORK_PTR(dip, whichfork); 846 mp = ip->i_mount; 847 switch (XFS_IFORK_FORMAT(ip, whichfork)) { 848 case XFS_DINODE_FMT_LOCAL: 849 if ((iip->ili_fields & dataflag[whichfork]) && 850 (ifp->if_bytes > 0)) { 851 ASSERT(ifp->if_u1.if_data != NULL); 852 ASSERT(ifp->if_bytes <= XFS_IFORK_SIZE(ip, whichfork)); 853 memcpy(cp, ifp->if_u1.if_data, ifp->if_bytes); 854 } 855 break; 856 857 case XFS_DINODE_FMT_EXTENTS: 858 ASSERT((ifp->if_flags & XFS_IFEXTENTS) || 859 !(iip->ili_fields & extflag[whichfork])); 860 if ((iip->ili_fields & extflag[whichfork]) && 861 (ifp->if_bytes > 0)) { 862 ASSERT(xfs_iext_get_ext(ifp, 0)); 863 ASSERT(XFS_IFORK_NEXTENTS(ip, whichfork) > 0); 864 (void)xfs_iextents_copy(ip, (xfs_bmbt_rec_t *)cp, 865 whichfork); 866 } 867 break; 868 869 case XFS_DINODE_FMT_BTREE: 870 if ((iip->ili_fields & brootflag[whichfork]) && 871 (ifp->if_broot_bytes > 0)) { 872 ASSERT(ifp->if_broot != NULL); 873 ASSERT(XFS_BMAP_BMDR_SPACE(ifp->if_broot) <= 874 XFS_IFORK_SIZE(ip, whichfork)); 875 xfs_bmbt_to_bmdr(mp, ifp->if_broot, ifp->if_broot_bytes, 876 (xfs_bmdr_block_t *)cp, 877 XFS_DFORK_SIZE(dip, mp, whichfork)); 878 } 879 break; 880 881 case XFS_DINODE_FMT_DEV: 882 if (iip->ili_fields & XFS_ILOG_DEV) { 883 ASSERT(whichfork == XFS_DATA_FORK); 884 xfs_dinode_put_rdev(dip, ip->i_df.if_u2.if_rdev); 885 } 886 break; 887 888 case XFS_DINODE_FMT_UUID: 889 if (iip->ili_fields & XFS_ILOG_UUID) { 890 ASSERT(whichfork == XFS_DATA_FORK); 891 memcpy(XFS_DFORK_DPTR(dip), 892 &ip->i_df.if_u2.if_uuid, 893 sizeof(uuid_t)); 894 } 895 break; 896 897 default: 898 ASSERT(0); 899 break; 900 } 901 } 902 903 /* 904 * Return a pointer to the extent record at file index idx. 905 */ 906 xfs_bmbt_rec_host_t * 907 xfs_iext_get_ext( 908 xfs_ifork_t *ifp, /* inode fork pointer */ 909 xfs_extnum_t idx) /* index of target extent */ 910 { 911 ASSERT(idx >= 0); 912 ASSERT(idx < ifp->if_bytes / sizeof(xfs_bmbt_rec_t)); 913 914 if ((ifp->if_flags & XFS_IFEXTIREC) && (idx == 0)) { 915 return ifp->if_u1.if_ext_irec->er_extbuf; 916 } else if (ifp->if_flags & XFS_IFEXTIREC) { 917 xfs_ext_irec_t *erp; /* irec pointer */ 918 int erp_idx = 0; /* irec index */ 919 xfs_extnum_t page_idx = idx; /* ext index in target list */ 920 921 erp = xfs_iext_idx_to_irec(ifp, &page_idx, &erp_idx, 0); 922 return &erp->er_extbuf[page_idx]; 923 } else if (ifp->if_bytes) { 924 return &ifp->if_u1.if_extents[idx]; 925 } else { 926 return NULL; 927 } 928 } 929 930 /* 931 * Insert new item(s) into the extent records for incore inode 932 * fork 'ifp'. 'count' new items are inserted at index 'idx'. 933 */ 934 void 935 xfs_iext_insert( 936 xfs_inode_t *ip, /* incore inode pointer */ 937 xfs_extnum_t idx, /* starting index of new items */ 938 xfs_extnum_t count, /* number of inserted items */ 939 xfs_bmbt_irec_t *new, /* items to insert */ 940 int state) /* type of extent conversion */ 941 { 942 xfs_ifork_t *ifp = (state & BMAP_ATTRFORK) ? ip->i_afp : &ip->i_df; 943 xfs_extnum_t i; /* extent record index */ 944 945 trace_xfs_iext_insert(ip, idx, new, state, _RET_IP_); 946 947 ASSERT(ifp->if_flags & XFS_IFEXTENTS); 948 xfs_iext_add(ifp, idx, count); 949 for (i = idx; i < idx + count; i++, new++) 950 xfs_bmbt_set_all(xfs_iext_get_ext(ifp, i), new); 951 } 952 953 /* 954 * This is called when the amount of space required for incore file 955 * extents needs to be increased. The ext_diff parameter stores the 956 * number of new extents being added and the idx parameter contains 957 * the extent index where the new extents will be added. If the new 958 * extents are being appended, then we just need to (re)allocate and 959 * initialize the space. Otherwise, if the new extents are being 960 * inserted into the middle of the existing entries, a bit more work 961 * is required to make room for the new extents to be inserted. The 962 * caller is responsible for filling in the new extent entries upon 963 * return. 964 */ 965 void 966 xfs_iext_add( 967 xfs_ifork_t *ifp, /* inode fork pointer */ 968 xfs_extnum_t idx, /* index to begin adding exts */ 969 int ext_diff) /* number of extents to add */ 970 { 971 int byte_diff; /* new bytes being added */ 972 int new_size; /* size of extents after adding */ 973 xfs_extnum_t nextents; /* number of extents in file */ 974 975 nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t); 976 ASSERT((idx >= 0) && (idx <= nextents)); 977 byte_diff = ext_diff * sizeof(xfs_bmbt_rec_t); 978 new_size = ifp->if_bytes + byte_diff; 979 /* 980 * If the new number of extents (nextents + ext_diff) 981 * fits inside the inode, then continue to use the inline 982 * extent buffer. 983 */ 984 if (nextents + ext_diff <= XFS_INLINE_EXTS) { 985 if (idx < nextents) { 986 memmove(&ifp->if_u2.if_inline_ext[idx + ext_diff], 987 &ifp->if_u2.if_inline_ext[idx], 988 (nextents - idx) * sizeof(xfs_bmbt_rec_t)); 989 memset(&ifp->if_u2.if_inline_ext[idx], 0, byte_diff); 990 } 991 ifp->if_u1.if_extents = ifp->if_u2.if_inline_ext; 992 ifp->if_real_bytes = 0; 993 } 994 /* 995 * Otherwise use a linear (direct) extent list. 996 * If the extents are currently inside the inode, 997 * xfs_iext_realloc_direct will switch us from 998 * inline to direct extent allocation mode. 999 */ 1000 else if (nextents + ext_diff <= XFS_LINEAR_EXTS) { 1001 xfs_iext_realloc_direct(ifp, new_size); 1002 if (idx < nextents) { 1003 memmove(&ifp->if_u1.if_extents[idx + ext_diff], 1004 &ifp->if_u1.if_extents[idx], 1005 (nextents - idx) * sizeof(xfs_bmbt_rec_t)); 1006 memset(&ifp->if_u1.if_extents[idx], 0, byte_diff); 1007 } 1008 } 1009 /* Indirection array */ 1010 else { 1011 xfs_ext_irec_t *erp; 1012 int erp_idx = 0; 1013 int page_idx = idx; 1014 1015 ASSERT(nextents + ext_diff > XFS_LINEAR_EXTS); 1016 if (ifp->if_flags & XFS_IFEXTIREC) { 1017 erp = xfs_iext_idx_to_irec(ifp, &page_idx, &erp_idx, 1); 1018 } else { 1019 xfs_iext_irec_init(ifp); 1020 ASSERT(ifp->if_flags & XFS_IFEXTIREC); 1021 erp = ifp->if_u1.if_ext_irec; 1022 } 1023 /* Extents fit in target extent page */ 1024 if (erp && erp->er_extcount + ext_diff <= XFS_LINEAR_EXTS) { 1025 if (page_idx < erp->er_extcount) { 1026 memmove(&erp->er_extbuf[page_idx + ext_diff], 1027 &erp->er_extbuf[page_idx], 1028 (erp->er_extcount - page_idx) * 1029 sizeof(xfs_bmbt_rec_t)); 1030 memset(&erp->er_extbuf[page_idx], 0, byte_diff); 1031 } 1032 erp->er_extcount += ext_diff; 1033 xfs_iext_irec_update_extoffs(ifp, erp_idx + 1, ext_diff); 1034 } 1035 /* Insert a new extent page */ 1036 else if (erp) { 1037 xfs_iext_add_indirect_multi(ifp, 1038 erp_idx, page_idx, ext_diff); 1039 } 1040 /* 1041 * If extent(s) are being appended to the last page in 1042 * the indirection array and the new extent(s) don't fit 1043 * in the page, then erp is NULL and erp_idx is set to 1044 * the next index needed in the indirection array. 1045 */ 1046 else { 1047 uint count = ext_diff; 1048 1049 while (count) { 1050 erp = xfs_iext_irec_new(ifp, erp_idx); 1051 erp->er_extcount = min(count, XFS_LINEAR_EXTS); 1052 count -= erp->er_extcount; 1053 if (count) 1054 erp_idx++; 1055 } 1056 } 1057 } 1058 ifp->if_bytes = new_size; 1059 } 1060 1061 /* 1062 * This is called when incore extents are being added to the indirection 1063 * array and the new extents do not fit in the target extent list. The 1064 * erp_idx parameter contains the irec index for the target extent list 1065 * in the indirection array, and the idx parameter contains the extent 1066 * index within the list. The number of extents being added is stored 1067 * in the count parameter. 1068 * 1069 * |-------| |-------| 1070 * | | | | idx - number of extents before idx 1071 * | idx | | count | 1072 * | | | | count - number of extents being inserted at idx 1073 * |-------| |-------| 1074 * | count | | nex2 | nex2 - number of extents after idx + count 1075 * |-------| |-------| 1076 */ 1077 void 1078 xfs_iext_add_indirect_multi( 1079 xfs_ifork_t *ifp, /* inode fork pointer */ 1080 int erp_idx, /* target extent irec index */ 1081 xfs_extnum_t idx, /* index within target list */ 1082 int count) /* new extents being added */ 1083 { 1084 int byte_diff; /* new bytes being added */ 1085 xfs_ext_irec_t *erp; /* pointer to irec entry */ 1086 xfs_extnum_t ext_diff; /* number of extents to add */ 1087 xfs_extnum_t ext_cnt; /* new extents still needed */ 1088 xfs_extnum_t nex2; /* extents after idx + count */ 1089 xfs_bmbt_rec_t *nex2_ep = NULL; /* temp list for nex2 extents */ 1090 int nlists; /* number of irec's (lists) */ 1091 1092 ASSERT(ifp->if_flags & XFS_IFEXTIREC); 1093 erp = &ifp->if_u1.if_ext_irec[erp_idx]; 1094 nex2 = erp->er_extcount - idx; 1095 nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ; 1096 1097 /* 1098 * Save second part of target extent list 1099 * (all extents past */ 1100 if (nex2) { 1101 byte_diff = nex2 * sizeof(xfs_bmbt_rec_t); 1102 nex2_ep = (xfs_bmbt_rec_t *) kmem_alloc(byte_diff, KM_NOFS); 1103 memmove(nex2_ep, &erp->er_extbuf[idx], byte_diff); 1104 erp->er_extcount -= nex2; 1105 xfs_iext_irec_update_extoffs(ifp, erp_idx + 1, -nex2); 1106 memset(&erp->er_extbuf[idx], 0, byte_diff); 1107 } 1108 1109 /* 1110 * Add the new extents to the end of the target 1111 * list, then allocate new irec record(s) and 1112 * extent buffer(s) as needed to store the rest 1113 * of the new extents. 1114 */ 1115 ext_cnt = count; 1116 ext_diff = MIN(ext_cnt, (int)XFS_LINEAR_EXTS - erp->er_extcount); 1117 if (ext_diff) { 1118 erp->er_extcount += ext_diff; 1119 xfs_iext_irec_update_extoffs(ifp, erp_idx + 1, ext_diff); 1120 ext_cnt -= ext_diff; 1121 } 1122 while (ext_cnt) { 1123 erp_idx++; 1124 erp = xfs_iext_irec_new(ifp, erp_idx); 1125 ext_diff = MIN(ext_cnt, (int)XFS_LINEAR_EXTS); 1126 erp->er_extcount = ext_diff; 1127 xfs_iext_irec_update_extoffs(ifp, erp_idx + 1, ext_diff); 1128 ext_cnt -= ext_diff; 1129 } 1130 1131 /* Add nex2 extents back to indirection array */ 1132 if (nex2) { 1133 xfs_extnum_t ext_avail; 1134 int i; 1135 1136 byte_diff = nex2 * sizeof(xfs_bmbt_rec_t); 1137 ext_avail = XFS_LINEAR_EXTS - erp->er_extcount; 1138 i = 0; 1139 /* 1140 * If nex2 extents fit in the current page, append 1141 * nex2_ep after the new extents. 1142 */ 1143 if (nex2 <= ext_avail) { 1144 i = erp->er_extcount; 1145 } 1146 /* 1147 * Otherwise, check if space is available in the 1148 * next page. 1149 */ 1150 else if ((erp_idx < nlists - 1) && 1151 (nex2 <= (ext_avail = XFS_LINEAR_EXTS - 1152 ifp->if_u1.if_ext_irec[erp_idx+1].er_extcount))) { 1153 erp_idx++; 1154 erp++; 1155 /* Create a hole for nex2 extents */ 1156 memmove(&erp->er_extbuf[nex2], erp->er_extbuf, 1157 erp->er_extcount * sizeof(xfs_bmbt_rec_t)); 1158 } 1159 /* 1160 * Final choice, create a new extent page for 1161 * nex2 extents. 1162 */ 1163 else { 1164 erp_idx++; 1165 erp = xfs_iext_irec_new(ifp, erp_idx); 1166 } 1167 memmove(&erp->er_extbuf[i], nex2_ep, byte_diff); 1168 kmem_free(nex2_ep); 1169 erp->er_extcount += nex2; 1170 xfs_iext_irec_update_extoffs(ifp, erp_idx + 1, nex2); 1171 } 1172 } 1173 1174 /* 1175 * This is called when the amount of space required for incore file 1176 * extents needs to be decreased. The ext_diff parameter stores the 1177 * number of extents to be removed and the idx parameter contains 1178 * the extent index where the extents will be removed from. 1179 * 1180 * If the amount of space needed has decreased below the linear 1181 * limit, XFS_IEXT_BUFSZ, then switch to using the contiguous 1182 * extent array. Otherwise, use kmem_realloc() to adjust the 1183 * size to what is needed. 1184 */ 1185 void 1186 xfs_iext_remove( 1187 xfs_inode_t *ip, /* incore inode pointer */ 1188 xfs_extnum_t idx, /* index to begin removing exts */ 1189 int ext_diff, /* number of extents to remove */ 1190 int state) /* type of extent conversion */ 1191 { 1192 xfs_ifork_t *ifp = (state & BMAP_ATTRFORK) ? ip->i_afp : &ip->i_df; 1193 xfs_extnum_t nextents; /* number of extents in file */ 1194 int new_size; /* size of extents after removal */ 1195 1196 trace_xfs_iext_remove(ip, idx, state, _RET_IP_); 1197 1198 ASSERT(ext_diff > 0); 1199 nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t); 1200 new_size = (nextents - ext_diff) * sizeof(xfs_bmbt_rec_t); 1201 1202 if (new_size == 0) { 1203 xfs_iext_destroy(ifp); 1204 } else if (ifp->if_flags & XFS_IFEXTIREC) { 1205 xfs_iext_remove_indirect(ifp, idx, ext_diff); 1206 } else if (ifp->if_real_bytes) { 1207 xfs_iext_remove_direct(ifp, idx, ext_diff); 1208 } else { 1209 xfs_iext_remove_inline(ifp, idx, ext_diff); 1210 } 1211 ifp->if_bytes = new_size; 1212 } 1213 1214 /* 1215 * This removes ext_diff extents from the inline buffer, beginning 1216 * at extent index idx. 1217 */ 1218 void 1219 xfs_iext_remove_inline( 1220 xfs_ifork_t *ifp, /* inode fork pointer */ 1221 xfs_extnum_t idx, /* index to begin removing exts */ 1222 int ext_diff) /* number of extents to remove */ 1223 { 1224 int nextents; /* number of extents in file */ 1225 1226 ASSERT(!(ifp->if_flags & XFS_IFEXTIREC)); 1227 ASSERT(idx < XFS_INLINE_EXTS); 1228 nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t); 1229 ASSERT(((nextents - ext_diff) > 0) && 1230 (nextents - ext_diff) < XFS_INLINE_EXTS); 1231 1232 if (idx + ext_diff < nextents) { 1233 memmove(&ifp->if_u2.if_inline_ext[idx], 1234 &ifp->if_u2.if_inline_ext[idx + ext_diff], 1235 (nextents - (idx + ext_diff)) * 1236 sizeof(xfs_bmbt_rec_t)); 1237 memset(&ifp->if_u2.if_inline_ext[nextents - ext_diff], 1238 0, ext_diff * sizeof(xfs_bmbt_rec_t)); 1239 } else { 1240 memset(&ifp->if_u2.if_inline_ext[idx], 0, 1241 ext_diff * sizeof(xfs_bmbt_rec_t)); 1242 } 1243 } 1244 1245 /* 1246 * This removes ext_diff extents from a linear (direct) extent list, 1247 * beginning at extent index idx. If the extents are being removed 1248 * from the end of the list (ie. truncate) then we just need to re- 1249 * allocate the list to remove the extra space. Otherwise, if the 1250 * extents are being removed from the middle of the existing extent 1251 * entries, then we first need to move the extent records beginning 1252 * at idx + ext_diff up in the list to overwrite the records being 1253 * removed, then remove the extra space via kmem_realloc. 1254 */ 1255 void 1256 xfs_iext_remove_direct( 1257 xfs_ifork_t *ifp, /* inode fork pointer */ 1258 xfs_extnum_t idx, /* index to begin removing exts */ 1259 int ext_diff) /* number of extents to remove */ 1260 { 1261 xfs_extnum_t nextents; /* number of extents in file */ 1262 int new_size; /* size of extents after removal */ 1263 1264 ASSERT(!(ifp->if_flags & XFS_IFEXTIREC)); 1265 new_size = ifp->if_bytes - 1266 (ext_diff * sizeof(xfs_bmbt_rec_t)); 1267 nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t); 1268 1269 if (new_size == 0) { 1270 xfs_iext_destroy(ifp); 1271 return; 1272 } 1273 /* Move extents up in the list (if needed) */ 1274 if (idx + ext_diff < nextents) { 1275 memmove(&ifp->if_u1.if_extents[idx], 1276 &ifp->if_u1.if_extents[idx + ext_diff], 1277 (nextents - (idx + ext_diff)) * 1278 sizeof(xfs_bmbt_rec_t)); 1279 } 1280 memset(&ifp->if_u1.if_extents[nextents - ext_diff], 1281 0, ext_diff * sizeof(xfs_bmbt_rec_t)); 1282 /* 1283 * Reallocate the direct extent list. If the extents 1284 * will fit inside the inode then xfs_iext_realloc_direct 1285 * will switch from direct to inline extent allocation 1286 * mode for us. 1287 */ 1288 xfs_iext_realloc_direct(ifp, new_size); 1289 ifp->if_bytes = new_size; 1290 } 1291 1292 /* 1293 * This is called when incore extents are being removed from the 1294 * indirection array and the extents being removed span multiple extent 1295 * buffers. The idx parameter contains the file extent index where we 1296 * want to begin removing extents, and the count parameter contains 1297 * how many extents need to be removed. 1298 * 1299 * |-------| |-------| 1300 * | nex1 | | | nex1 - number of extents before idx 1301 * |-------| | count | 1302 * | | | | count - number of extents being removed at idx 1303 * | count | |-------| 1304 * | | | nex2 | nex2 - number of extents after idx + count 1305 * |-------| |-------| 1306 */ 1307 void 1308 xfs_iext_remove_indirect( 1309 xfs_ifork_t *ifp, /* inode fork pointer */ 1310 xfs_extnum_t idx, /* index to begin removing extents */ 1311 int count) /* number of extents to remove */ 1312 { 1313 xfs_ext_irec_t *erp; /* indirection array pointer */ 1314 int erp_idx = 0; /* indirection array index */ 1315 xfs_extnum_t ext_cnt; /* extents left to remove */ 1316 xfs_extnum_t ext_diff; /* extents to remove in current list */ 1317 xfs_extnum_t nex1; /* number of extents before idx */ 1318 xfs_extnum_t nex2; /* extents after idx + count */ 1319 int page_idx = idx; /* index in target extent list */ 1320 1321 ASSERT(ifp->if_flags & XFS_IFEXTIREC); 1322 erp = xfs_iext_idx_to_irec(ifp, &page_idx, &erp_idx, 0); 1323 ASSERT(erp != NULL); 1324 nex1 = page_idx; 1325 ext_cnt = count; 1326 while (ext_cnt) { 1327 nex2 = MAX((erp->er_extcount - (nex1 + ext_cnt)), 0); 1328 ext_diff = MIN(ext_cnt, (erp->er_extcount - nex1)); 1329 /* 1330 * Check for deletion of entire list; 1331 * xfs_iext_irec_remove() updates extent offsets. 1332 */ 1333 if (ext_diff == erp->er_extcount) { 1334 xfs_iext_irec_remove(ifp, erp_idx); 1335 ext_cnt -= ext_diff; 1336 nex1 = 0; 1337 if (ext_cnt) { 1338 ASSERT(erp_idx < ifp->if_real_bytes / 1339 XFS_IEXT_BUFSZ); 1340 erp = &ifp->if_u1.if_ext_irec[erp_idx]; 1341 nex1 = 0; 1342 continue; 1343 } else { 1344 break; 1345 } 1346 } 1347 /* Move extents up (if needed) */ 1348 if (nex2) { 1349 memmove(&erp->er_extbuf[nex1], 1350 &erp->er_extbuf[nex1 + ext_diff], 1351 nex2 * sizeof(xfs_bmbt_rec_t)); 1352 } 1353 /* Zero out rest of page */ 1354 memset(&erp->er_extbuf[nex1 + nex2], 0, (XFS_IEXT_BUFSZ - 1355 ((nex1 + nex2) * sizeof(xfs_bmbt_rec_t)))); 1356 /* Update remaining counters */ 1357 erp->er_extcount -= ext_diff; 1358 xfs_iext_irec_update_extoffs(ifp, erp_idx + 1, -ext_diff); 1359 ext_cnt -= ext_diff; 1360 nex1 = 0; 1361 erp_idx++; 1362 erp++; 1363 } 1364 ifp->if_bytes -= count * sizeof(xfs_bmbt_rec_t); 1365 xfs_iext_irec_compact(ifp); 1366 } 1367 1368 /* 1369 * Create, destroy, or resize a linear (direct) block of extents. 1370 */ 1371 void 1372 xfs_iext_realloc_direct( 1373 xfs_ifork_t *ifp, /* inode fork pointer */ 1374 int new_size) /* new size of extents after adding */ 1375 { 1376 int rnew_size; /* real new size of extents */ 1377 1378 rnew_size = new_size; 1379 1380 ASSERT(!(ifp->if_flags & XFS_IFEXTIREC) || 1381 ((new_size >= 0) && (new_size <= XFS_IEXT_BUFSZ) && 1382 (new_size != ifp->if_real_bytes))); 1383 1384 /* Free extent records */ 1385 if (new_size == 0) { 1386 xfs_iext_destroy(ifp); 1387 } 1388 /* Resize direct extent list and zero any new bytes */ 1389 else if (ifp->if_real_bytes) { 1390 /* Check if extents will fit inside the inode */ 1391 if (new_size <= XFS_INLINE_EXTS * sizeof(xfs_bmbt_rec_t)) { 1392 xfs_iext_direct_to_inline(ifp, new_size / 1393 (uint)sizeof(xfs_bmbt_rec_t)); 1394 ifp->if_bytes = new_size; 1395 return; 1396 } 1397 if (!is_power_of_2(new_size)){ 1398 rnew_size = roundup_pow_of_two(new_size); 1399 } 1400 if (rnew_size != ifp->if_real_bytes) { 1401 ifp->if_u1.if_extents = 1402 kmem_realloc(ifp->if_u1.if_extents, 1403 rnew_size, KM_NOFS); 1404 } 1405 if (rnew_size > ifp->if_real_bytes) { 1406 memset(&ifp->if_u1.if_extents[ifp->if_bytes / 1407 (uint)sizeof(xfs_bmbt_rec_t)], 0, 1408 rnew_size - ifp->if_real_bytes); 1409 } 1410 } 1411 /* Switch from the inline extent buffer to a direct extent list */ 1412 else { 1413 if (!is_power_of_2(new_size)) { 1414 rnew_size = roundup_pow_of_two(new_size); 1415 } 1416 xfs_iext_inline_to_direct(ifp, rnew_size); 1417 } 1418 ifp->if_real_bytes = rnew_size; 1419 ifp->if_bytes = new_size; 1420 } 1421 1422 /* 1423 * Switch from linear (direct) extent records to inline buffer. 1424 */ 1425 void 1426 xfs_iext_direct_to_inline( 1427 xfs_ifork_t *ifp, /* inode fork pointer */ 1428 xfs_extnum_t nextents) /* number of extents in file */ 1429 { 1430 ASSERT(ifp->if_flags & XFS_IFEXTENTS); 1431 ASSERT(nextents <= XFS_INLINE_EXTS); 1432 /* 1433 * The inline buffer was zeroed when we switched 1434 * from inline to direct extent allocation mode, 1435 * so we don't need to clear it here. 1436 */ 1437 memcpy(ifp->if_u2.if_inline_ext, ifp->if_u1.if_extents, 1438 nextents * sizeof(xfs_bmbt_rec_t)); 1439 kmem_free(ifp->if_u1.if_extents); 1440 ifp->if_u1.if_extents = ifp->if_u2.if_inline_ext; 1441 ifp->if_real_bytes = 0; 1442 } 1443 1444 /* 1445 * Switch from inline buffer to linear (direct) extent records. 1446 * new_size should already be rounded up to the next power of 2 1447 * by the caller (when appropriate), so use new_size as it is. 1448 * However, since new_size may be rounded up, we can't update 1449 * if_bytes here. It is the caller's responsibility to update 1450 * if_bytes upon return. 1451 */ 1452 void 1453 xfs_iext_inline_to_direct( 1454 xfs_ifork_t *ifp, /* inode fork pointer */ 1455 int new_size) /* number of extents in file */ 1456 { 1457 ifp->if_u1.if_extents = kmem_alloc(new_size, KM_NOFS); 1458 memset(ifp->if_u1.if_extents, 0, new_size); 1459 if (ifp->if_bytes) { 1460 memcpy(ifp->if_u1.if_extents, ifp->if_u2.if_inline_ext, 1461 ifp->if_bytes); 1462 memset(ifp->if_u2.if_inline_ext, 0, XFS_INLINE_EXTS * 1463 sizeof(xfs_bmbt_rec_t)); 1464 } 1465 ifp->if_real_bytes = new_size; 1466 } 1467 1468 /* 1469 * Resize an extent indirection array to new_size bytes. 1470 */ 1471 STATIC void 1472 xfs_iext_realloc_indirect( 1473 xfs_ifork_t *ifp, /* inode fork pointer */ 1474 int new_size) /* new indirection array size */ 1475 { 1476 int nlists; /* number of irec's (ex lists) */ 1477 int size; /* current indirection array size */ 1478 1479 ASSERT(ifp->if_flags & XFS_IFEXTIREC); 1480 nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ; 1481 size = nlists * sizeof(xfs_ext_irec_t); 1482 ASSERT(ifp->if_real_bytes); 1483 ASSERT((new_size >= 0) && (new_size != size)); 1484 if (new_size == 0) { 1485 xfs_iext_destroy(ifp); 1486 } else { 1487 ifp->if_u1.if_ext_irec = 1488 kmem_realloc(ifp->if_u1.if_ext_irec, new_size, KM_NOFS); 1489 } 1490 } 1491 1492 /* 1493 * Switch from indirection array to linear (direct) extent allocations. 1494 */ 1495 STATIC void 1496 xfs_iext_indirect_to_direct( 1497 xfs_ifork_t *ifp) /* inode fork pointer */ 1498 { 1499 xfs_bmbt_rec_host_t *ep; /* extent record pointer */ 1500 xfs_extnum_t nextents; /* number of extents in file */ 1501 int size; /* size of file extents */ 1502 1503 ASSERT(ifp->if_flags & XFS_IFEXTIREC); 1504 nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t); 1505 ASSERT(nextents <= XFS_LINEAR_EXTS); 1506 size = nextents * sizeof(xfs_bmbt_rec_t); 1507 1508 xfs_iext_irec_compact_pages(ifp); 1509 ASSERT(ifp->if_real_bytes == XFS_IEXT_BUFSZ); 1510 1511 ep = ifp->if_u1.if_ext_irec->er_extbuf; 1512 kmem_free(ifp->if_u1.if_ext_irec); 1513 ifp->if_flags &= ~XFS_IFEXTIREC; 1514 ifp->if_u1.if_extents = ep; 1515 ifp->if_bytes = size; 1516 if (nextents < XFS_LINEAR_EXTS) { 1517 xfs_iext_realloc_direct(ifp, size); 1518 } 1519 } 1520 1521 /* 1522 * Remove all records from the indirection array. 1523 */ 1524 STATIC void 1525 xfs_iext_irec_remove_all( 1526 struct xfs_ifork *ifp) 1527 { 1528 int nlists; 1529 int i; 1530 1531 ASSERT(ifp->if_flags & XFS_IFEXTIREC); 1532 nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ; 1533 for (i = 0; i < nlists; i++) 1534 kmem_free(ifp->if_u1.if_ext_irec[i].er_extbuf); 1535 kmem_free(ifp->if_u1.if_ext_irec); 1536 ifp->if_flags &= ~XFS_IFEXTIREC; 1537 } 1538 1539 /* 1540 * Free incore file extents. 1541 */ 1542 void 1543 xfs_iext_destroy( 1544 xfs_ifork_t *ifp) /* inode fork pointer */ 1545 { 1546 if (ifp->if_flags & XFS_IFEXTIREC) { 1547 xfs_iext_irec_remove_all(ifp); 1548 } else if (ifp->if_real_bytes) { 1549 kmem_free(ifp->if_u1.if_extents); 1550 } else if (ifp->if_bytes) { 1551 memset(ifp->if_u2.if_inline_ext, 0, XFS_INLINE_EXTS * 1552 sizeof(xfs_bmbt_rec_t)); 1553 } 1554 ifp->if_u1.if_extents = NULL; 1555 ifp->if_real_bytes = 0; 1556 ifp->if_bytes = 0; 1557 } 1558 1559 /* 1560 * Return a pointer to the extent record for file system block bno. 1561 */ 1562 xfs_bmbt_rec_host_t * /* pointer to found extent record */ 1563 xfs_iext_bno_to_ext( 1564 xfs_ifork_t *ifp, /* inode fork pointer */ 1565 xfs_fileoff_t bno, /* block number to search for */ 1566 xfs_extnum_t *idxp) /* index of target extent */ 1567 { 1568 xfs_bmbt_rec_host_t *base; /* pointer to first extent */ 1569 xfs_filblks_t blockcount = 0; /* number of blocks in extent */ 1570 xfs_bmbt_rec_host_t *ep = NULL; /* pointer to target extent */ 1571 xfs_ext_irec_t *erp = NULL; /* indirection array pointer */ 1572 int high; /* upper boundary in search */ 1573 xfs_extnum_t idx = 0; /* index of target extent */ 1574 int low; /* lower boundary in search */ 1575 xfs_extnum_t nextents; /* number of file extents */ 1576 xfs_fileoff_t startoff = 0; /* start offset of extent */ 1577 1578 nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t); 1579 if (nextents == 0) { 1580 *idxp = 0; 1581 return NULL; 1582 } 1583 low = 0; 1584 if (ifp->if_flags & XFS_IFEXTIREC) { 1585 /* Find target extent list */ 1586 int erp_idx = 0; 1587 erp = xfs_iext_bno_to_irec(ifp, bno, &erp_idx); 1588 base = erp->er_extbuf; 1589 high = erp->er_extcount - 1; 1590 } else { 1591 base = ifp->if_u1.if_extents; 1592 high = nextents - 1; 1593 } 1594 /* Binary search extent records */ 1595 while (low <= high) { 1596 idx = (low + high) >> 1; 1597 ep = base + idx; 1598 startoff = xfs_bmbt_get_startoff(ep); 1599 blockcount = xfs_bmbt_get_blockcount(ep); 1600 if (bno < startoff) { 1601 high = idx - 1; 1602 } else if (bno >= startoff + blockcount) { 1603 low = idx + 1; 1604 } else { 1605 /* Convert back to file-based extent index */ 1606 if (ifp->if_flags & XFS_IFEXTIREC) { 1607 idx += erp->er_extoff; 1608 } 1609 *idxp = idx; 1610 return ep; 1611 } 1612 } 1613 /* Convert back to file-based extent index */ 1614 if (ifp->if_flags & XFS_IFEXTIREC) { 1615 idx += erp->er_extoff; 1616 } 1617 if (bno >= startoff + blockcount) { 1618 if (++idx == nextents) { 1619 ep = NULL; 1620 } else { 1621 ep = xfs_iext_get_ext(ifp, idx); 1622 } 1623 } 1624 *idxp = idx; 1625 return ep; 1626 } 1627 1628 /* 1629 * Return a pointer to the indirection array entry containing the 1630 * extent record for filesystem block bno. Store the index of the 1631 * target irec in *erp_idxp. 1632 */ 1633 xfs_ext_irec_t * /* pointer to found extent record */ 1634 xfs_iext_bno_to_irec( 1635 xfs_ifork_t *ifp, /* inode fork pointer */ 1636 xfs_fileoff_t bno, /* block number to search for */ 1637 int *erp_idxp) /* irec index of target ext list */ 1638 { 1639 xfs_ext_irec_t *erp = NULL; /* indirection array pointer */ 1640 xfs_ext_irec_t *erp_next; /* next indirection array entry */ 1641 int erp_idx; /* indirection array index */ 1642 int nlists; /* number of extent irec's (lists) */ 1643 int high; /* binary search upper limit */ 1644 int low; /* binary search lower limit */ 1645 1646 ASSERT(ifp->if_flags & XFS_IFEXTIREC); 1647 nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ; 1648 erp_idx = 0; 1649 low = 0; 1650 high = nlists - 1; 1651 while (low <= high) { 1652 erp_idx = (low + high) >> 1; 1653 erp = &ifp->if_u1.if_ext_irec[erp_idx]; 1654 erp_next = erp_idx < nlists - 1 ? erp + 1 : NULL; 1655 if (bno < xfs_bmbt_get_startoff(erp->er_extbuf)) { 1656 high = erp_idx - 1; 1657 } else if (erp_next && bno >= 1658 xfs_bmbt_get_startoff(erp_next->er_extbuf)) { 1659 low = erp_idx + 1; 1660 } else { 1661 break; 1662 } 1663 } 1664 *erp_idxp = erp_idx; 1665 return erp; 1666 } 1667 1668 /* 1669 * Return a pointer to the indirection array entry containing the 1670 * extent record at file extent index *idxp. Store the index of the 1671 * target irec in *erp_idxp and store the page index of the target 1672 * extent record in *idxp. 1673 */ 1674 xfs_ext_irec_t * 1675 xfs_iext_idx_to_irec( 1676 xfs_ifork_t *ifp, /* inode fork pointer */ 1677 xfs_extnum_t *idxp, /* extent index (file -> page) */ 1678 int *erp_idxp, /* pointer to target irec */ 1679 int realloc) /* new bytes were just added */ 1680 { 1681 xfs_ext_irec_t *prev; /* pointer to previous irec */ 1682 xfs_ext_irec_t *erp = NULL; /* pointer to current irec */ 1683 int erp_idx; /* indirection array index */ 1684 int nlists; /* number of irec's (ex lists) */ 1685 int high; /* binary search upper limit */ 1686 int low; /* binary search lower limit */ 1687 xfs_extnum_t page_idx = *idxp; /* extent index in target list */ 1688 1689 ASSERT(ifp->if_flags & XFS_IFEXTIREC); 1690 ASSERT(page_idx >= 0); 1691 ASSERT(page_idx <= ifp->if_bytes / sizeof(xfs_bmbt_rec_t)); 1692 ASSERT(page_idx < ifp->if_bytes / sizeof(xfs_bmbt_rec_t) || realloc); 1693 1694 nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ; 1695 erp_idx = 0; 1696 low = 0; 1697 high = nlists - 1; 1698 1699 /* Binary search extent irec's */ 1700 while (low <= high) { 1701 erp_idx = (low + high) >> 1; 1702 erp = &ifp->if_u1.if_ext_irec[erp_idx]; 1703 prev = erp_idx > 0 ? erp - 1 : NULL; 1704 if (page_idx < erp->er_extoff || (page_idx == erp->er_extoff && 1705 realloc && prev && prev->er_extcount < XFS_LINEAR_EXTS)) { 1706 high = erp_idx - 1; 1707 } else if (page_idx > erp->er_extoff + erp->er_extcount || 1708 (page_idx == erp->er_extoff + erp->er_extcount && 1709 !realloc)) { 1710 low = erp_idx + 1; 1711 } else if (page_idx == erp->er_extoff + erp->er_extcount && 1712 erp->er_extcount == XFS_LINEAR_EXTS) { 1713 ASSERT(realloc); 1714 page_idx = 0; 1715 erp_idx++; 1716 erp = erp_idx < nlists ? erp + 1 : NULL; 1717 break; 1718 } else { 1719 page_idx -= erp->er_extoff; 1720 break; 1721 } 1722 } 1723 *idxp = page_idx; 1724 *erp_idxp = erp_idx; 1725 return erp; 1726 } 1727 1728 /* 1729 * Allocate and initialize an indirection array once the space needed 1730 * for incore extents increases above XFS_IEXT_BUFSZ. 1731 */ 1732 void 1733 xfs_iext_irec_init( 1734 xfs_ifork_t *ifp) /* inode fork pointer */ 1735 { 1736 xfs_ext_irec_t *erp; /* indirection array pointer */ 1737 xfs_extnum_t nextents; /* number of extents in file */ 1738 1739 ASSERT(!(ifp->if_flags & XFS_IFEXTIREC)); 1740 nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t); 1741 ASSERT(nextents <= XFS_LINEAR_EXTS); 1742 1743 erp = kmem_alloc(sizeof(xfs_ext_irec_t), KM_NOFS); 1744 1745 if (nextents == 0) { 1746 ifp->if_u1.if_extents = kmem_alloc(XFS_IEXT_BUFSZ, KM_NOFS); 1747 } else if (!ifp->if_real_bytes) { 1748 xfs_iext_inline_to_direct(ifp, XFS_IEXT_BUFSZ); 1749 } else if (ifp->if_real_bytes < XFS_IEXT_BUFSZ) { 1750 xfs_iext_realloc_direct(ifp, XFS_IEXT_BUFSZ); 1751 } 1752 erp->er_extbuf = ifp->if_u1.if_extents; 1753 erp->er_extcount = nextents; 1754 erp->er_extoff = 0; 1755 1756 ifp->if_flags |= XFS_IFEXTIREC; 1757 ifp->if_real_bytes = XFS_IEXT_BUFSZ; 1758 ifp->if_bytes = nextents * sizeof(xfs_bmbt_rec_t); 1759 ifp->if_u1.if_ext_irec = erp; 1760 1761 return; 1762 } 1763 1764 /* 1765 * Allocate and initialize a new entry in the indirection array. 1766 */ 1767 xfs_ext_irec_t * 1768 xfs_iext_irec_new( 1769 xfs_ifork_t *ifp, /* inode fork pointer */ 1770 int erp_idx) /* index for new irec */ 1771 { 1772 xfs_ext_irec_t *erp; /* indirection array pointer */ 1773 int i; /* loop counter */ 1774 int nlists; /* number of irec's (ex lists) */ 1775 1776 ASSERT(ifp->if_flags & XFS_IFEXTIREC); 1777 nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ; 1778 1779 /* Resize indirection array */ 1780 xfs_iext_realloc_indirect(ifp, ++nlists * 1781 sizeof(xfs_ext_irec_t)); 1782 /* 1783 * Move records down in the array so the 1784 * new page can use erp_idx. 1785 */ 1786 erp = ifp->if_u1.if_ext_irec; 1787 for (i = nlists - 1; i > erp_idx; i--) { 1788 memmove(&erp[i], &erp[i-1], sizeof(xfs_ext_irec_t)); 1789 } 1790 ASSERT(i == erp_idx); 1791 1792 /* Initialize new extent record */ 1793 erp = ifp->if_u1.if_ext_irec; 1794 erp[erp_idx].er_extbuf = kmem_alloc(XFS_IEXT_BUFSZ, KM_NOFS); 1795 ifp->if_real_bytes = nlists * XFS_IEXT_BUFSZ; 1796 memset(erp[erp_idx].er_extbuf, 0, XFS_IEXT_BUFSZ); 1797 erp[erp_idx].er_extcount = 0; 1798 erp[erp_idx].er_extoff = erp_idx > 0 ? 1799 erp[erp_idx-1].er_extoff + erp[erp_idx-1].er_extcount : 0; 1800 return (&erp[erp_idx]); 1801 } 1802 1803 /* 1804 * Remove a record from the indirection array. 1805 */ 1806 void 1807 xfs_iext_irec_remove( 1808 xfs_ifork_t *ifp, /* inode fork pointer */ 1809 int erp_idx) /* irec index to remove */ 1810 { 1811 xfs_ext_irec_t *erp; /* indirection array pointer */ 1812 int i; /* loop counter */ 1813 int nlists; /* number of irec's (ex lists) */ 1814 1815 ASSERT(ifp->if_flags & XFS_IFEXTIREC); 1816 nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ; 1817 erp = &ifp->if_u1.if_ext_irec[erp_idx]; 1818 if (erp->er_extbuf) { 1819 xfs_iext_irec_update_extoffs(ifp, erp_idx + 1, 1820 -erp->er_extcount); 1821 kmem_free(erp->er_extbuf); 1822 } 1823 /* Compact extent records */ 1824 erp = ifp->if_u1.if_ext_irec; 1825 for (i = erp_idx; i < nlists - 1; i++) { 1826 memmove(&erp[i], &erp[i+1], sizeof(xfs_ext_irec_t)); 1827 } 1828 /* 1829 * Manually free the last extent record from the indirection 1830 * array. A call to xfs_iext_realloc_indirect() with a size 1831 * of zero would result in a call to xfs_iext_destroy() which 1832 * would in turn call this function again, creating a nasty 1833 * infinite loop. 1834 */ 1835 if (--nlists) { 1836 xfs_iext_realloc_indirect(ifp, 1837 nlists * sizeof(xfs_ext_irec_t)); 1838 } else { 1839 kmem_free(ifp->if_u1.if_ext_irec); 1840 } 1841 ifp->if_real_bytes = nlists * XFS_IEXT_BUFSZ; 1842 } 1843 1844 /* 1845 * This is called to clean up large amounts of unused memory allocated 1846 * by the indirection array. Before compacting anything though, verify 1847 * that the indirection array is still needed and switch back to the 1848 * linear extent list (or even the inline buffer) if possible. The 1849 * compaction policy is as follows: 1850 * 1851 * Full Compaction: Extents fit into a single page (or inline buffer) 1852 * Partial Compaction: Extents occupy less than 50% of allocated space 1853 * No Compaction: Extents occupy at least 50% of allocated space 1854 */ 1855 void 1856 xfs_iext_irec_compact( 1857 xfs_ifork_t *ifp) /* inode fork pointer */ 1858 { 1859 xfs_extnum_t nextents; /* number of extents in file */ 1860 int nlists; /* number of irec's (ex lists) */ 1861 1862 ASSERT(ifp->if_flags & XFS_IFEXTIREC); 1863 nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ; 1864 nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t); 1865 1866 if (nextents == 0) { 1867 xfs_iext_destroy(ifp); 1868 } else if (nextents <= XFS_INLINE_EXTS) { 1869 xfs_iext_indirect_to_direct(ifp); 1870 xfs_iext_direct_to_inline(ifp, nextents); 1871 } else if (nextents <= XFS_LINEAR_EXTS) { 1872 xfs_iext_indirect_to_direct(ifp); 1873 } else if (nextents < (nlists * XFS_LINEAR_EXTS) >> 1) { 1874 xfs_iext_irec_compact_pages(ifp); 1875 } 1876 } 1877 1878 /* 1879 * Combine extents from neighboring extent pages. 1880 */ 1881 void 1882 xfs_iext_irec_compact_pages( 1883 xfs_ifork_t *ifp) /* inode fork pointer */ 1884 { 1885 xfs_ext_irec_t *erp, *erp_next;/* pointers to irec entries */ 1886 int erp_idx = 0; /* indirection array index */ 1887 int nlists; /* number of irec's (ex lists) */ 1888 1889 ASSERT(ifp->if_flags & XFS_IFEXTIREC); 1890 nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ; 1891 while (erp_idx < nlists - 1) { 1892 erp = &ifp->if_u1.if_ext_irec[erp_idx]; 1893 erp_next = erp + 1; 1894 if (erp_next->er_extcount <= 1895 (XFS_LINEAR_EXTS - erp->er_extcount)) { 1896 memcpy(&erp->er_extbuf[erp->er_extcount], 1897 erp_next->er_extbuf, erp_next->er_extcount * 1898 sizeof(xfs_bmbt_rec_t)); 1899 erp->er_extcount += erp_next->er_extcount; 1900 /* 1901 * Free page before removing extent record 1902 * so er_extoffs don't get modified in 1903 * xfs_iext_irec_remove. 1904 */ 1905 kmem_free(erp_next->er_extbuf); 1906 erp_next->er_extbuf = NULL; 1907 xfs_iext_irec_remove(ifp, erp_idx + 1); 1908 nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ; 1909 } else { 1910 erp_idx++; 1911 } 1912 } 1913 } 1914 1915 /* 1916 * This is called to update the er_extoff field in the indirection 1917 * array when extents have been added or removed from one of the 1918 * extent lists. erp_idx contains the irec index to begin updating 1919 * at and ext_diff contains the number of extents that were added 1920 * or removed. 1921 */ 1922 void 1923 xfs_iext_irec_update_extoffs( 1924 xfs_ifork_t *ifp, /* inode fork pointer */ 1925 int erp_idx, /* irec index to update */ 1926 int ext_diff) /* number of new extents */ 1927 { 1928 int i; /* loop counter */ 1929 int nlists; /* number of irec's (ex lists */ 1930 1931 ASSERT(ifp->if_flags & XFS_IFEXTIREC); 1932 nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ; 1933 for (i = erp_idx; i < nlists; i++) { 1934 ifp->if_u1.if_ext_irec[i].er_extoff += ext_diff; 1935 } 1936 } 1937