1 /* 2 * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc. 3 * Copyright (c) 2013 Red Hat, Inc. 4 * All Rights Reserved. 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License as 8 * published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope that it would be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 18 */ 19 #include "xfs.h" 20 #include "xfs_fs.h" 21 #include "xfs_format.h" 22 #include "xfs_log_format.h" 23 #include "xfs_trans_resv.h" 24 #include "xfs_mount.h" 25 #include "xfs_da_format.h" 26 #include "xfs_da_btree.h" 27 #include "xfs_inode.h" 28 #include "xfs_dir2.h" 29 #include "xfs_dir2_priv.h" 30 #include "xfs_error.h" 31 #include "xfs_trans.h" 32 #include "xfs_buf_item.h" 33 #include "xfs_cksum.h" 34 #include "xfs_log.h" 35 36 /* 37 * Check the consistency of the data block. 38 * The input can also be a block-format directory. 39 * Return 0 is the buffer is good, otherwise an error. 40 */ 41 int 42 __xfs_dir3_data_check( 43 struct xfs_inode *dp, /* incore inode pointer */ 44 struct xfs_buf *bp) /* data block's buffer */ 45 { 46 xfs_dir2_dataptr_t addr; /* addr for leaf lookup */ 47 xfs_dir2_data_free_t *bf; /* bestfree table */ 48 xfs_dir2_block_tail_t *btp=NULL; /* block tail */ 49 int count; /* count of entries found */ 50 xfs_dir2_data_hdr_t *hdr; /* data block header */ 51 xfs_dir2_data_entry_t *dep; /* data entry */ 52 xfs_dir2_data_free_t *dfp; /* bestfree entry */ 53 xfs_dir2_data_unused_t *dup; /* unused entry */ 54 char *endp; /* end of useful data */ 55 int freeseen; /* mask of bestfrees seen */ 56 xfs_dahash_t hash; /* hash of current name */ 57 int i; /* leaf index */ 58 int lastfree; /* last entry was unused */ 59 xfs_dir2_leaf_entry_t *lep=NULL; /* block leaf entries */ 60 xfs_mount_t *mp; /* filesystem mount point */ 61 char *p; /* current data position */ 62 int stale; /* count of stale leaves */ 63 struct xfs_name name; 64 const struct xfs_dir_ops *ops; 65 struct xfs_da_geometry *geo; 66 67 mp = bp->b_target->bt_mount; 68 geo = mp->m_dir_geo; 69 70 /* 71 * We can be passed a null dp here from a verifier, so we need to go the 72 * hard way to get them. 73 */ 74 ops = xfs_dir_get_ops(mp, dp); 75 76 hdr = bp->b_addr; 77 p = (char *)ops->data_entry_p(hdr); 78 79 switch (hdr->magic) { 80 case cpu_to_be32(XFS_DIR3_BLOCK_MAGIC): 81 case cpu_to_be32(XFS_DIR2_BLOCK_MAGIC): 82 btp = xfs_dir2_block_tail_p(geo, hdr); 83 lep = xfs_dir2_block_leaf_p(btp); 84 endp = (char *)lep; 85 86 /* 87 * The number of leaf entries is limited by the size of the 88 * block and the amount of space used by the data entries. 89 * We don't know how much space is used by the data entries yet, 90 * so just ensure that the count falls somewhere inside the 91 * block right now. 92 */ 93 XFS_WANT_CORRUPTED_RETURN(mp, be32_to_cpu(btp->count) < 94 ((char *)btp - p) / sizeof(struct xfs_dir2_leaf_entry)); 95 break; 96 case cpu_to_be32(XFS_DIR3_DATA_MAGIC): 97 case cpu_to_be32(XFS_DIR2_DATA_MAGIC): 98 endp = (char *)hdr + geo->blksize; 99 break; 100 default: 101 XFS_ERROR_REPORT("Bad Magic", XFS_ERRLEVEL_LOW, mp); 102 return -EFSCORRUPTED; 103 } 104 105 /* 106 * Account for zero bestfree entries. 107 */ 108 bf = ops->data_bestfree_p(hdr); 109 count = lastfree = freeseen = 0; 110 if (!bf[0].length) { 111 XFS_WANT_CORRUPTED_RETURN(mp, !bf[0].offset); 112 freeseen |= 1 << 0; 113 } 114 if (!bf[1].length) { 115 XFS_WANT_CORRUPTED_RETURN(mp, !bf[1].offset); 116 freeseen |= 1 << 1; 117 } 118 if (!bf[2].length) { 119 XFS_WANT_CORRUPTED_RETURN(mp, !bf[2].offset); 120 freeseen |= 1 << 2; 121 } 122 123 XFS_WANT_CORRUPTED_RETURN(mp, be16_to_cpu(bf[0].length) >= 124 be16_to_cpu(bf[1].length)); 125 XFS_WANT_CORRUPTED_RETURN(mp, be16_to_cpu(bf[1].length) >= 126 be16_to_cpu(bf[2].length)); 127 /* 128 * Loop over the data/unused entries. 129 */ 130 while (p < endp) { 131 dup = (xfs_dir2_data_unused_t *)p; 132 /* 133 * If it's unused, look for the space in the bestfree table. 134 * If we find it, account for that, else make sure it 135 * doesn't need to be there. 136 */ 137 if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) { 138 XFS_WANT_CORRUPTED_RETURN(mp, lastfree == 0); 139 XFS_WANT_CORRUPTED_RETURN(mp, endp >= 140 p + be16_to_cpu(dup->length)); 141 XFS_WANT_CORRUPTED_RETURN(mp, 142 be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup)) == 143 (char *)dup - (char *)hdr); 144 dfp = xfs_dir2_data_freefind(hdr, bf, dup); 145 if (dfp) { 146 i = (int)(dfp - bf); 147 XFS_WANT_CORRUPTED_RETURN(mp, 148 (freeseen & (1 << i)) == 0); 149 freeseen |= 1 << i; 150 } else { 151 XFS_WANT_CORRUPTED_RETURN(mp, 152 be16_to_cpu(dup->length) <= 153 be16_to_cpu(bf[2].length)); 154 } 155 p += be16_to_cpu(dup->length); 156 lastfree = 1; 157 continue; 158 } 159 /* 160 * It's a real entry. Validate the fields. 161 * If this is a block directory then make sure it's 162 * in the leaf section of the block. 163 * The linear search is crude but this is DEBUG code. 164 */ 165 dep = (xfs_dir2_data_entry_t *)p; 166 XFS_WANT_CORRUPTED_RETURN(mp, dep->namelen != 0); 167 XFS_WANT_CORRUPTED_RETURN(mp, 168 !xfs_dir_ino_validate(mp, be64_to_cpu(dep->inumber))); 169 XFS_WANT_CORRUPTED_RETURN(mp, endp >= 170 p + ops->data_entsize(dep->namelen)); 171 XFS_WANT_CORRUPTED_RETURN(mp, 172 be16_to_cpu(*ops->data_entry_tag_p(dep)) == 173 (char *)dep - (char *)hdr); 174 XFS_WANT_CORRUPTED_RETURN(mp, 175 ops->data_get_ftype(dep) < XFS_DIR3_FT_MAX); 176 count++; 177 lastfree = 0; 178 if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || 179 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)) { 180 addr = xfs_dir2_db_off_to_dataptr(geo, geo->datablk, 181 (xfs_dir2_data_aoff_t) 182 ((char *)dep - (char *)hdr)); 183 name.name = dep->name; 184 name.len = dep->namelen; 185 hash = mp->m_dirnameops->hashname(&name); 186 for (i = 0; i < be32_to_cpu(btp->count); i++) { 187 if (be32_to_cpu(lep[i].address) == addr && 188 be32_to_cpu(lep[i].hashval) == hash) 189 break; 190 } 191 XFS_WANT_CORRUPTED_RETURN(mp, 192 i < be32_to_cpu(btp->count)); 193 } 194 p += ops->data_entsize(dep->namelen); 195 } 196 /* 197 * Need to have seen all the entries and all the bestfree slots. 198 */ 199 XFS_WANT_CORRUPTED_RETURN(mp, freeseen == 7); 200 if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || 201 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)) { 202 for (i = stale = 0; i < be32_to_cpu(btp->count); i++) { 203 if (lep[i].address == 204 cpu_to_be32(XFS_DIR2_NULL_DATAPTR)) 205 stale++; 206 if (i > 0) 207 XFS_WANT_CORRUPTED_RETURN(mp, 208 be32_to_cpu(lep[i].hashval) >= 209 be32_to_cpu(lep[i - 1].hashval)); 210 } 211 XFS_WANT_CORRUPTED_RETURN(mp, count == 212 be32_to_cpu(btp->count) - be32_to_cpu(btp->stale)); 213 XFS_WANT_CORRUPTED_RETURN(mp, stale == be32_to_cpu(btp->stale)); 214 } 215 return 0; 216 } 217 218 static bool 219 xfs_dir3_data_verify( 220 struct xfs_buf *bp) 221 { 222 struct xfs_mount *mp = bp->b_target->bt_mount; 223 struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr; 224 225 if (xfs_sb_version_hascrc(&mp->m_sb)) { 226 if (hdr3->magic != cpu_to_be32(XFS_DIR3_DATA_MAGIC)) 227 return false; 228 if (!uuid_equal(&hdr3->uuid, &mp->m_sb.sb_meta_uuid)) 229 return false; 230 if (be64_to_cpu(hdr3->blkno) != bp->b_bn) 231 return false; 232 if (!xfs_log_check_lsn(mp, be64_to_cpu(hdr3->lsn))) 233 return false; 234 } else { 235 if (hdr3->magic != cpu_to_be32(XFS_DIR2_DATA_MAGIC)) 236 return false; 237 } 238 if (__xfs_dir3_data_check(NULL, bp)) 239 return false; 240 return true; 241 } 242 243 /* 244 * Readahead of the first block of the directory when it is opened is completely 245 * oblivious to the format of the directory. Hence we can either get a block 246 * format buffer or a data format buffer on readahead. 247 */ 248 static void 249 xfs_dir3_data_reada_verify( 250 struct xfs_buf *bp) 251 { 252 struct xfs_dir2_data_hdr *hdr = bp->b_addr; 253 254 switch (hdr->magic) { 255 case cpu_to_be32(XFS_DIR2_BLOCK_MAGIC): 256 case cpu_to_be32(XFS_DIR3_BLOCK_MAGIC): 257 bp->b_ops = &xfs_dir3_block_buf_ops; 258 bp->b_ops->verify_read(bp); 259 return; 260 case cpu_to_be32(XFS_DIR2_DATA_MAGIC): 261 case cpu_to_be32(XFS_DIR3_DATA_MAGIC): 262 bp->b_ops = &xfs_dir3_data_buf_ops; 263 bp->b_ops->verify_read(bp); 264 return; 265 default: 266 xfs_buf_ioerror(bp, -EFSCORRUPTED); 267 xfs_verifier_error(bp); 268 break; 269 } 270 } 271 272 static void 273 xfs_dir3_data_read_verify( 274 struct xfs_buf *bp) 275 { 276 struct xfs_mount *mp = bp->b_target->bt_mount; 277 278 if (xfs_sb_version_hascrc(&mp->m_sb) && 279 !xfs_buf_verify_cksum(bp, XFS_DIR3_DATA_CRC_OFF)) 280 xfs_buf_ioerror(bp, -EFSBADCRC); 281 else if (!xfs_dir3_data_verify(bp)) 282 xfs_buf_ioerror(bp, -EFSCORRUPTED); 283 284 if (bp->b_error) 285 xfs_verifier_error(bp); 286 } 287 288 static void 289 xfs_dir3_data_write_verify( 290 struct xfs_buf *bp) 291 { 292 struct xfs_mount *mp = bp->b_target->bt_mount; 293 struct xfs_buf_log_item *bip = bp->b_fspriv; 294 struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr; 295 296 if (!xfs_dir3_data_verify(bp)) { 297 xfs_buf_ioerror(bp, -EFSCORRUPTED); 298 xfs_verifier_error(bp); 299 return; 300 } 301 302 if (!xfs_sb_version_hascrc(&mp->m_sb)) 303 return; 304 305 if (bip) 306 hdr3->lsn = cpu_to_be64(bip->bli_item.li_lsn); 307 308 xfs_buf_update_cksum(bp, XFS_DIR3_DATA_CRC_OFF); 309 } 310 311 const struct xfs_buf_ops xfs_dir3_data_buf_ops = { 312 .name = "xfs_dir3_data", 313 .verify_read = xfs_dir3_data_read_verify, 314 .verify_write = xfs_dir3_data_write_verify, 315 }; 316 317 static const struct xfs_buf_ops xfs_dir3_data_reada_buf_ops = { 318 .name = "xfs_dir3_data_reada", 319 .verify_read = xfs_dir3_data_reada_verify, 320 .verify_write = xfs_dir3_data_write_verify, 321 }; 322 323 324 int 325 xfs_dir3_data_read( 326 struct xfs_trans *tp, 327 struct xfs_inode *dp, 328 xfs_dablk_t bno, 329 xfs_daddr_t mapped_bno, 330 struct xfs_buf **bpp) 331 { 332 int err; 333 334 err = xfs_da_read_buf(tp, dp, bno, mapped_bno, bpp, 335 XFS_DATA_FORK, &xfs_dir3_data_buf_ops); 336 if (!err && tp && *bpp) 337 xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_DATA_BUF); 338 return err; 339 } 340 341 int 342 xfs_dir3_data_readahead( 343 struct xfs_inode *dp, 344 xfs_dablk_t bno, 345 xfs_daddr_t mapped_bno) 346 { 347 return xfs_da_reada_buf(dp, bno, mapped_bno, 348 XFS_DATA_FORK, &xfs_dir3_data_reada_buf_ops); 349 } 350 351 /* 352 * Given a data block and an unused entry from that block, 353 * return the bestfree entry if any that corresponds to it. 354 */ 355 xfs_dir2_data_free_t * 356 xfs_dir2_data_freefind( 357 struct xfs_dir2_data_hdr *hdr, /* data block header */ 358 struct xfs_dir2_data_free *bf, /* bestfree table pointer */ 359 struct xfs_dir2_data_unused *dup) /* unused space */ 360 { 361 xfs_dir2_data_free_t *dfp; /* bestfree entry */ 362 xfs_dir2_data_aoff_t off; /* offset value needed */ 363 #ifdef DEBUG 364 int matched; /* matched the value */ 365 int seenzero; /* saw a 0 bestfree entry */ 366 #endif 367 368 off = (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr); 369 370 #ifdef DEBUG 371 /* 372 * Validate some consistency in the bestfree table. 373 * Check order, non-overlapping entries, and if we find the 374 * one we're looking for it has to be exact. 375 */ 376 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || 377 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) || 378 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || 379 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)); 380 for (dfp = &bf[0], seenzero = matched = 0; 381 dfp < &bf[XFS_DIR2_DATA_FD_COUNT]; 382 dfp++) { 383 if (!dfp->offset) { 384 ASSERT(!dfp->length); 385 seenzero = 1; 386 continue; 387 } 388 ASSERT(seenzero == 0); 389 if (be16_to_cpu(dfp->offset) == off) { 390 matched = 1; 391 ASSERT(dfp->length == dup->length); 392 } else if (off < be16_to_cpu(dfp->offset)) 393 ASSERT(off + be16_to_cpu(dup->length) <= be16_to_cpu(dfp->offset)); 394 else 395 ASSERT(be16_to_cpu(dfp->offset) + be16_to_cpu(dfp->length) <= off); 396 ASSERT(matched || be16_to_cpu(dfp->length) >= be16_to_cpu(dup->length)); 397 if (dfp > &bf[0]) 398 ASSERT(be16_to_cpu(dfp[-1].length) >= be16_to_cpu(dfp[0].length)); 399 } 400 #endif 401 /* 402 * If this is smaller than the smallest bestfree entry, 403 * it can't be there since they're sorted. 404 */ 405 if (be16_to_cpu(dup->length) < 406 be16_to_cpu(bf[XFS_DIR2_DATA_FD_COUNT - 1].length)) 407 return NULL; 408 /* 409 * Look at the three bestfree entries for our guy. 410 */ 411 for (dfp = &bf[0]; dfp < &bf[XFS_DIR2_DATA_FD_COUNT]; dfp++) { 412 if (!dfp->offset) 413 return NULL; 414 if (be16_to_cpu(dfp->offset) == off) 415 return dfp; 416 } 417 /* 418 * Didn't find it. This only happens if there are duplicate lengths. 419 */ 420 return NULL; 421 } 422 423 /* 424 * Insert an unused-space entry into the bestfree table. 425 */ 426 xfs_dir2_data_free_t * /* entry inserted */ 427 xfs_dir2_data_freeinsert( 428 struct xfs_dir2_data_hdr *hdr, /* data block pointer */ 429 struct xfs_dir2_data_free *dfp, /* bestfree table pointer */ 430 struct xfs_dir2_data_unused *dup, /* unused space */ 431 int *loghead) /* log the data header (out) */ 432 { 433 xfs_dir2_data_free_t new; /* new bestfree entry */ 434 435 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || 436 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || 437 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) || 438 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)); 439 440 new.length = dup->length; 441 new.offset = cpu_to_be16((char *)dup - (char *)hdr); 442 443 /* 444 * Insert at position 0, 1, or 2; or not at all. 445 */ 446 if (be16_to_cpu(new.length) > be16_to_cpu(dfp[0].length)) { 447 dfp[2] = dfp[1]; 448 dfp[1] = dfp[0]; 449 dfp[0] = new; 450 *loghead = 1; 451 return &dfp[0]; 452 } 453 if (be16_to_cpu(new.length) > be16_to_cpu(dfp[1].length)) { 454 dfp[2] = dfp[1]; 455 dfp[1] = new; 456 *loghead = 1; 457 return &dfp[1]; 458 } 459 if (be16_to_cpu(new.length) > be16_to_cpu(dfp[2].length)) { 460 dfp[2] = new; 461 *loghead = 1; 462 return &dfp[2]; 463 } 464 return NULL; 465 } 466 467 /* 468 * Remove a bestfree entry from the table. 469 */ 470 STATIC void 471 xfs_dir2_data_freeremove( 472 struct xfs_dir2_data_hdr *hdr, /* data block header */ 473 struct xfs_dir2_data_free *bf, /* bestfree table pointer */ 474 struct xfs_dir2_data_free *dfp, /* bestfree entry pointer */ 475 int *loghead) /* out: log data header */ 476 { 477 478 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || 479 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || 480 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) || 481 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)); 482 483 /* 484 * It's the first entry, slide the next 2 up. 485 */ 486 if (dfp == &bf[0]) { 487 bf[0] = bf[1]; 488 bf[1] = bf[2]; 489 } 490 /* 491 * It's the second entry, slide the 3rd entry up. 492 */ 493 else if (dfp == &bf[1]) 494 bf[1] = bf[2]; 495 /* 496 * Must be the last entry. 497 */ 498 else 499 ASSERT(dfp == &bf[2]); 500 /* 501 * Clear the 3rd entry, must be zero now. 502 */ 503 bf[2].length = 0; 504 bf[2].offset = 0; 505 *loghead = 1; 506 } 507 508 /* 509 * Given a data block, reconstruct its bestfree map. 510 */ 511 void 512 xfs_dir2_data_freescan_int( 513 struct xfs_da_geometry *geo, 514 const struct xfs_dir_ops *ops, 515 struct xfs_dir2_data_hdr *hdr, 516 int *loghead) 517 { 518 xfs_dir2_block_tail_t *btp; /* block tail */ 519 xfs_dir2_data_entry_t *dep; /* active data entry */ 520 xfs_dir2_data_unused_t *dup; /* unused data entry */ 521 struct xfs_dir2_data_free *bf; 522 char *endp; /* end of block's data */ 523 char *p; /* current entry pointer */ 524 525 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || 526 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) || 527 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || 528 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)); 529 530 /* 531 * Start by clearing the table. 532 */ 533 bf = ops->data_bestfree_p(hdr); 534 memset(bf, 0, sizeof(*bf) * XFS_DIR2_DATA_FD_COUNT); 535 *loghead = 1; 536 /* 537 * Set up pointers. 538 */ 539 p = (char *)ops->data_entry_p(hdr); 540 if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || 541 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)) { 542 btp = xfs_dir2_block_tail_p(geo, hdr); 543 endp = (char *)xfs_dir2_block_leaf_p(btp); 544 } else 545 endp = (char *)hdr + geo->blksize; 546 /* 547 * Loop over the block's entries. 548 */ 549 while (p < endp) { 550 dup = (xfs_dir2_data_unused_t *)p; 551 /* 552 * If it's a free entry, insert it. 553 */ 554 if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) { 555 ASSERT((char *)dup - (char *)hdr == 556 be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup))); 557 xfs_dir2_data_freeinsert(hdr, bf, dup, loghead); 558 p += be16_to_cpu(dup->length); 559 } 560 /* 561 * For active entries, check their tags and skip them. 562 */ 563 else { 564 dep = (xfs_dir2_data_entry_t *)p; 565 ASSERT((char *)dep - (char *)hdr == 566 be16_to_cpu(*ops->data_entry_tag_p(dep))); 567 p += ops->data_entsize(dep->namelen); 568 } 569 } 570 } 571 572 void 573 xfs_dir2_data_freescan( 574 struct xfs_inode *dp, 575 struct xfs_dir2_data_hdr *hdr, 576 int *loghead) 577 { 578 return xfs_dir2_data_freescan_int(dp->i_mount->m_dir_geo, dp->d_ops, 579 hdr, loghead); 580 } 581 582 /* 583 * Initialize a data block at the given block number in the directory. 584 * Give back the buffer for the created block. 585 */ 586 int /* error */ 587 xfs_dir3_data_init( 588 xfs_da_args_t *args, /* directory operation args */ 589 xfs_dir2_db_t blkno, /* logical dir block number */ 590 struct xfs_buf **bpp) /* output block buffer */ 591 { 592 struct xfs_buf *bp; /* block buffer */ 593 xfs_dir2_data_hdr_t *hdr; /* data block header */ 594 xfs_inode_t *dp; /* incore directory inode */ 595 xfs_dir2_data_unused_t *dup; /* unused entry pointer */ 596 struct xfs_dir2_data_free *bf; 597 int error; /* error return value */ 598 int i; /* bestfree index */ 599 xfs_mount_t *mp; /* filesystem mount point */ 600 xfs_trans_t *tp; /* transaction pointer */ 601 int t; /* temp */ 602 603 dp = args->dp; 604 mp = dp->i_mount; 605 tp = args->trans; 606 /* 607 * Get the buffer set up for the block. 608 */ 609 error = xfs_da_get_buf(tp, dp, xfs_dir2_db_to_da(args->geo, blkno), 610 -1, &bp, XFS_DATA_FORK); 611 if (error) 612 return error; 613 bp->b_ops = &xfs_dir3_data_buf_ops; 614 xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_DATA_BUF); 615 616 /* 617 * Initialize the header. 618 */ 619 hdr = bp->b_addr; 620 if (xfs_sb_version_hascrc(&mp->m_sb)) { 621 struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr; 622 623 memset(hdr3, 0, sizeof(*hdr3)); 624 hdr3->magic = cpu_to_be32(XFS_DIR3_DATA_MAGIC); 625 hdr3->blkno = cpu_to_be64(bp->b_bn); 626 hdr3->owner = cpu_to_be64(dp->i_ino); 627 uuid_copy(&hdr3->uuid, &mp->m_sb.sb_meta_uuid); 628 629 } else 630 hdr->magic = cpu_to_be32(XFS_DIR2_DATA_MAGIC); 631 632 bf = dp->d_ops->data_bestfree_p(hdr); 633 bf[0].offset = cpu_to_be16(dp->d_ops->data_entry_offset); 634 for (i = 1; i < XFS_DIR2_DATA_FD_COUNT; i++) { 635 bf[i].length = 0; 636 bf[i].offset = 0; 637 } 638 639 /* 640 * Set up an unused entry for the block's body. 641 */ 642 dup = dp->d_ops->data_unused_p(hdr); 643 dup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG); 644 645 t = args->geo->blksize - (uint)dp->d_ops->data_entry_offset; 646 bf[0].length = cpu_to_be16(t); 647 dup->length = cpu_to_be16(t); 648 *xfs_dir2_data_unused_tag_p(dup) = cpu_to_be16((char *)dup - (char *)hdr); 649 /* 650 * Log it and return it. 651 */ 652 xfs_dir2_data_log_header(args, bp); 653 xfs_dir2_data_log_unused(args, bp, dup); 654 *bpp = bp; 655 return 0; 656 } 657 658 /* 659 * Log an active data entry from the block. 660 */ 661 void 662 xfs_dir2_data_log_entry( 663 struct xfs_da_args *args, 664 struct xfs_buf *bp, 665 xfs_dir2_data_entry_t *dep) /* data entry pointer */ 666 { 667 struct xfs_dir2_data_hdr *hdr = bp->b_addr; 668 669 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || 670 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) || 671 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || 672 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)); 673 674 xfs_trans_log_buf(args->trans, bp, (uint)((char *)dep - (char *)hdr), 675 (uint)((char *)(args->dp->d_ops->data_entry_tag_p(dep) + 1) - 676 (char *)hdr - 1)); 677 } 678 679 /* 680 * Log a data block header. 681 */ 682 void 683 xfs_dir2_data_log_header( 684 struct xfs_da_args *args, 685 struct xfs_buf *bp) 686 { 687 #ifdef DEBUG 688 struct xfs_dir2_data_hdr *hdr = bp->b_addr; 689 690 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || 691 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) || 692 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || 693 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)); 694 #endif 695 696 xfs_trans_log_buf(args->trans, bp, 0, 697 args->dp->d_ops->data_entry_offset - 1); 698 } 699 700 /* 701 * Log a data unused entry. 702 */ 703 void 704 xfs_dir2_data_log_unused( 705 struct xfs_da_args *args, 706 struct xfs_buf *bp, 707 xfs_dir2_data_unused_t *dup) /* data unused pointer */ 708 { 709 xfs_dir2_data_hdr_t *hdr = bp->b_addr; 710 711 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || 712 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) || 713 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || 714 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)); 715 716 /* 717 * Log the first part of the unused entry. 718 */ 719 xfs_trans_log_buf(args->trans, bp, (uint)((char *)dup - (char *)hdr), 720 (uint)((char *)&dup->length + sizeof(dup->length) - 721 1 - (char *)hdr)); 722 /* 723 * Log the end (tag) of the unused entry. 724 */ 725 xfs_trans_log_buf(args->trans, bp, 726 (uint)((char *)xfs_dir2_data_unused_tag_p(dup) - (char *)hdr), 727 (uint)((char *)xfs_dir2_data_unused_tag_p(dup) - (char *)hdr + 728 sizeof(xfs_dir2_data_off_t) - 1)); 729 } 730 731 /* 732 * Make a byte range in the data block unused. 733 * Its current contents are unimportant. 734 */ 735 void 736 xfs_dir2_data_make_free( 737 struct xfs_da_args *args, 738 struct xfs_buf *bp, 739 xfs_dir2_data_aoff_t offset, /* starting byte offset */ 740 xfs_dir2_data_aoff_t len, /* length in bytes */ 741 int *needlogp, /* out: log header */ 742 int *needscanp) /* out: regen bestfree */ 743 { 744 xfs_dir2_data_hdr_t *hdr; /* data block pointer */ 745 xfs_dir2_data_free_t *dfp; /* bestfree pointer */ 746 char *endptr; /* end of data area */ 747 int needscan; /* need to regen bestfree */ 748 xfs_dir2_data_unused_t *newdup; /* new unused entry */ 749 xfs_dir2_data_unused_t *postdup; /* unused entry after us */ 750 xfs_dir2_data_unused_t *prevdup; /* unused entry before us */ 751 struct xfs_dir2_data_free *bf; 752 753 hdr = bp->b_addr; 754 755 /* 756 * Figure out where the end of the data area is. 757 */ 758 if (hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || 759 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC)) 760 endptr = (char *)hdr + args->geo->blksize; 761 else { 762 xfs_dir2_block_tail_t *btp; /* block tail */ 763 764 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || 765 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)); 766 btp = xfs_dir2_block_tail_p(args->geo, hdr); 767 endptr = (char *)xfs_dir2_block_leaf_p(btp); 768 } 769 /* 770 * If this isn't the start of the block, then back up to 771 * the previous entry and see if it's free. 772 */ 773 if (offset > args->dp->d_ops->data_entry_offset) { 774 __be16 *tagp; /* tag just before us */ 775 776 tagp = (__be16 *)((char *)hdr + offset) - 1; 777 prevdup = (xfs_dir2_data_unused_t *)((char *)hdr + be16_to_cpu(*tagp)); 778 if (be16_to_cpu(prevdup->freetag) != XFS_DIR2_DATA_FREE_TAG) 779 prevdup = NULL; 780 } else 781 prevdup = NULL; 782 /* 783 * If this isn't the end of the block, see if the entry after 784 * us is free. 785 */ 786 if ((char *)hdr + offset + len < endptr) { 787 postdup = 788 (xfs_dir2_data_unused_t *)((char *)hdr + offset + len); 789 if (be16_to_cpu(postdup->freetag) != XFS_DIR2_DATA_FREE_TAG) 790 postdup = NULL; 791 } else 792 postdup = NULL; 793 ASSERT(*needscanp == 0); 794 needscan = 0; 795 /* 796 * Previous and following entries are both free, 797 * merge everything into a single free entry. 798 */ 799 bf = args->dp->d_ops->data_bestfree_p(hdr); 800 if (prevdup && postdup) { 801 xfs_dir2_data_free_t *dfp2; /* another bestfree pointer */ 802 803 /* 804 * See if prevdup and/or postdup are in bestfree table. 805 */ 806 dfp = xfs_dir2_data_freefind(hdr, bf, prevdup); 807 dfp2 = xfs_dir2_data_freefind(hdr, bf, postdup); 808 /* 809 * We need a rescan unless there are exactly 2 free entries 810 * namely our two. Then we know what's happening, otherwise 811 * since the third bestfree is there, there might be more 812 * entries. 813 */ 814 needscan = (bf[2].length != 0); 815 /* 816 * Fix up the new big freespace. 817 */ 818 be16_add_cpu(&prevdup->length, len + be16_to_cpu(postdup->length)); 819 *xfs_dir2_data_unused_tag_p(prevdup) = 820 cpu_to_be16((char *)prevdup - (char *)hdr); 821 xfs_dir2_data_log_unused(args, bp, prevdup); 822 if (!needscan) { 823 /* 824 * Has to be the case that entries 0 and 1 are 825 * dfp and dfp2 (don't know which is which), and 826 * entry 2 is empty. 827 * Remove entry 1 first then entry 0. 828 */ 829 ASSERT(dfp && dfp2); 830 if (dfp == &bf[1]) { 831 dfp = &bf[0]; 832 ASSERT(dfp2 == dfp); 833 dfp2 = &bf[1]; 834 } 835 xfs_dir2_data_freeremove(hdr, bf, dfp2, needlogp); 836 xfs_dir2_data_freeremove(hdr, bf, dfp, needlogp); 837 /* 838 * Now insert the new entry. 839 */ 840 dfp = xfs_dir2_data_freeinsert(hdr, bf, prevdup, 841 needlogp); 842 ASSERT(dfp == &bf[0]); 843 ASSERT(dfp->length == prevdup->length); 844 ASSERT(!dfp[1].length); 845 ASSERT(!dfp[2].length); 846 } 847 } 848 /* 849 * The entry before us is free, merge with it. 850 */ 851 else if (prevdup) { 852 dfp = xfs_dir2_data_freefind(hdr, bf, prevdup); 853 be16_add_cpu(&prevdup->length, len); 854 *xfs_dir2_data_unused_tag_p(prevdup) = 855 cpu_to_be16((char *)prevdup - (char *)hdr); 856 xfs_dir2_data_log_unused(args, bp, prevdup); 857 /* 858 * If the previous entry was in the table, the new entry 859 * is longer, so it will be in the table too. Remove 860 * the old one and add the new one. 861 */ 862 if (dfp) { 863 xfs_dir2_data_freeremove(hdr, bf, dfp, needlogp); 864 xfs_dir2_data_freeinsert(hdr, bf, prevdup, needlogp); 865 } 866 /* 867 * Otherwise we need a scan if the new entry is big enough. 868 */ 869 else { 870 needscan = be16_to_cpu(prevdup->length) > 871 be16_to_cpu(bf[2].length); 872 } 873 } 874 /* 875 * The following entry is free, merge with it. 876 */ 877 else if (postdup) { 878 dfp = xfs_dir2_data_freefind(hdr, bf, postdup); 879 newdup = (xfs_dir2_data_unused_t *)((char *)hdr + offset); 880 newdup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG); 881 newdup->length = cpu_to_be16(len + be16_to_cpu(postdup->length)); 882 *xfs_dir2_data_unused_tag_p(newdup) = 883 cpu_to_be16((char *)newdup - (char *)hdr); 884 xfs_dir2_data_log_unused(args, bp, newdup); 885 /* 886 * If the following entry was in the table, the new entry 887 * is longer, so it will be in the table too. Remove 888 * the old one and add the new one. 889 */ 890 if (dfp) { 891 xfs_dir2_data_freeremove(hdr, bf, dfp, needlogp); 892 xfs_dir2_data_freeinsert(hdr, bf, newdup, needlogp); 893 } 894 /* 895 * Otherwise we need a scan if the new entry is big enough. 896 */ 897 else { 898 needscan = be16_to_cpu(newdup->length) > 899 be16_to_cpu(bf[2].length); 900 } 901 } 902 /* 903 * Neither neighbor is free. Make a new entry. 904 */ 905 else { 906 newdup = (xfs_dir2_data_unused_t *)((char *)hdr + offset); 907 newdup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG); 908 newdup->length = cpu_to_be16(len); 909 *xfs_dir2_data_unused_tag_p(newdup) = 910 cpu_to_be16((char *)newdup - (char *)hdr); 911 xfs_dir2_data_log_unused(args, bp, newdup); 912 xfs_dir2_data_freeinsert(hdr, bf, newdup, needlogp); 913 } 914 *needscanp = needscan; 915 } 916 917 /* 918 * Take a byte range out of an existing unused space and make it un-free. 919 */ 920 void 921 xfs_dir2_data_use_free( 922 struct xfs_da_args *args, 923 struct xfs_buf *bp, 924 xfs_dir2_data_unused_t *dup, /* unused entry */ 925 xfs_dir2_data_aoff_t offset, /* starting offset to use */ 926 xfs_dir2_data_aoff_t len, /* length to use */ 927 int *needlogp, /* out: need to log header */ 928 int *needscanp) /* out: need regen bestfree */ 929 { 930 xfs_dir2_data_hdr_t *hdr; /* data block header */ 931 xfs_dir2_data_free_t *dfp; /* bestfree pointer */ 932 int matchback; /* matches end of freespace */ 933 int matchfront; /* matches start of freespace */ 934 int needscan; /* need to regen bestfree */ 935 xfs_dir2_data_unused_t *newdup; /* new unused entry */ 936 xfs_dir2_data_unused_t *newdup2; /* another new unused entry */ 937 int oldlen; /* old unused entry's length */ 938 struct xfs_dir2_data_free *bf; 939 940 hdr = bp->b_addr; 941 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) || 942 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) || 943 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) || 944 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)); 945 ASSERT(be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG); 946 ASSERT(offset >= (char *)dup - (char *)hdr); 947 ASSERT(offset + len <= (char *)dup + be16_to_cpu(dup->length) - (char *)hdr); 948 ASSERT((char *)dup - (char *)hdr == be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup))); 949 /* 950 * Look up the entry in the bestfree table. 951 */ 952 oldlen = be16_to_cpu(dup->length); 953 bf = args->dp->d_ops->data_bestfree_p(hdr); 954 dfp = xfs_dir2_data_freefind(hdr, bf, dup); 955 ASSERT(dfp || oldlen <= be16_to_cpu(bf[2].length)); 956 /* 957 * Check for alignment with front and back of the entry. 958 */ 959 matchfront = (char *)dup - (char *)hdr == offset; 960 matchback = (char *)dup + oldlen - (char *)hdr == offset + len; 961 ASSERT(*needscanp == 0); 962 needscan = 0; 963 /* 964 * If we matched it exactly we just need to get rid of it from 965 * the bestfree table. 966 */ 967 if (matchfront && matchback) { 968 if (dfp) { 969 needscan = (bf[2].offset != 0); 970 if (!needscan) 971 xfs_dir2_data_freeremove(hdr, bf, dfp, 972 needlogp); 973 } 974 } 975 /* 976 * We match the first part of the entry. 977 * Make a new entry with the remaining freespace. 978 */ 979 else if (matchfront) { 980 newdup = (xfs_dir2_data_unused_t *)((char *)hdr + offset + len); 981 newdup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG); 982 newdup->length = cpu_to_be16(oldlen - len); 983 *xfs_dir2_data_unused_tag_p(newdup) = 984 cpu_to_be16((char *)newdup - (char *)hdr); 985 xfs_dir2_data_log_unused(args, bp, newdup); 986 /* 987 * If it was in the table, remove it and add the new one. 988 */ 989 if (dfp) { 990 xfs_dir2_data_freeremove(hdr, bf, dfp, needlogp); 991 dfp = xfs_dir2_data_freeinsert(hdr, bf, newdup, 992 needlogp); 993 ASSERT(dfp != NULL); 994 ASSERT(dfp->length == newdup->length); 995 ASSERT(be16_to_cpu(dfp->offset) == (char *)newdup - (char *)hdr); 996 /* 997 * If we got inserted at the last slot, 998 * that means we don't know if there was a better 999 * choice for the last slot, or not. Rescan. 1000 */ 1001 needscan = dfp == &bf[2]; 1002 } 1003 } 1004 /* 1005 * We match the last part of the entry. 1006 * Trim the allocated space off the tail of the entry. 1007 */ 1008 else if (matchback) { 1009 newdup = dup; 1010 newdup->length = cpu_to_be16(((char *)hdr + offset) - (char *)newdup); 1011 *xfs_dir2_data_unused_tag_p(newdup) = 1012 cpu_to_be16((char *)newdup - (char *)hdr); 1013 xfs_dir2_data_log_unused(args, bp, newdup); 1014 /* 1015 * If it was in the table, remove it and add the new one. 1016 */ 1017 if (dfp) { 1018 xfs_dir2_data_freeremove(hdr, bf, dfp, needlogp); 1019 dfp = xfs_dir2_data_freeinsert(hdr, bf, newdup, 1020 needlogp); 1021 ASSERT(dfp != NULL); 1022 ASSERT(dfp->length == newdup->length); 1023 ASSERT(be16_to_cpu(dfp->offset) == (char *)newdup - (char *)hdr); 1024 /* 1025 * If we got inserted at the last slot, 1026 * that means we don't know if there was a better 1027 * choice for the last slot, or not. Rescan. 1028 */ 1029 needscan = dfp == &bf[2]; 1030 } 1031 } 1032 /* 1033 * Poking out the middle of an entry. 1034 * Make two new entries. 1035 */ 1036 else { 1037 newdup = dup; 1038 newdup->length = cpu_to_be16(((char *)hdr + offset) - (char *)newdup); 1039 *xfs_dir2_data_unused_tag_p(newdup) = 1040 cpu_to_be16((char *)newdup - (char *)hdr); 1041 xfs_dir2_data_log_unused(args, bp, newdup); 1042 newdup2 = (xfs_dir2_data_unused_t *)((char *)hdr + offset + len); 1043 newdup2->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG); 1044 newdup2->length = cpu_to_be16(oldlen - len - be16_to_cpu(newdup->length)); 1045 *xfs_dir2_data_unused_tag_p(newdup2) = 1046 cpu_to_be16((char *)newdup2 - (char *)hdr); 1047 xfs_dir2_data_log_unused(args, bp, newdup2); 1048 /* 1049 * If the old entry was in the table, we need to scan 1050 * if the 3rd entry was valid, since these entries 1051 * are smaller than the old one. 1052 * If we don't need to scan that means there were 1 or 2 1053 * entries in the table, and removing the old and adding 1054 * the 2 new will work. 1055 */ 1056 if (dfp) { 1057 needscan = (bf[2].length != 0); 1058 if (!needscan) { 1059 xfs_dir2_data_freeremove(hdr, bf, dfp, 1060 needlogp); 1061 xfs_dir2_data_freeinsert(hdr, bf, newdup, 1062 needlogp); 1063 xfs_dir2_data_freeinsert(hdr, bf, newdup2, 1064 needlogp); 1065 } 1066 } 1067 } 1068 *needscanp = needscan; 1069 } 1070