| 1 | /* |
| 2 | * Copyright (c) 2000-2002,2005 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 "xfs.h" |
| 19 | #include "xfs_fs.h" |
| 20 | #include "xfs_types.h" |
| 21 | #include "xfs_bit.h" |
| 22 | #include "xfs_log.h" |
| 23 | #include "xfs_trans.h" |
| 24 | #include "xfs_sb.h" |
| 25 | #include "xfs_ag.h" |
| 26 | #include "xfs_mount.h" |
| 27 | #include "xfs_bmap_btree.h" |
| 28 | #include "xfs_alloc_btree.h" |
| 29 | #include "xfs_ialloc_btree.h" |
| 30 | #include "xfs_dinode.h" |
| 31 | #include "xfs_inode.h" |
| 32 | #include "xfs_inode_item.h" |
| 33 | #include "xfs_btree.h" |
| 34 | #include "xfs_error.h" |
| 35 | #include "xfs_trace.h" |
| 36 | |
| 37 | /* |
| 38 | * Cursor allocation zone. |
| 39 | */ |
| 40 | kmem_zone_t *xfs_btree_cur_zone; |
| 41 | |
| 42 | /* |
| 43 | * Btree magic numbers. |
| 44 | */ |
| 45 | const __uint32_t xfs_magics[XFS_BTNUM_MAX] = { |
| 46 | XFS_ABTB_MAGIC, XFS_ABTC_MAGIC, XFS_BMAP_MAGIC, XFS_IBT_MAGIC |
| 47 | }; |
| 48 | |
| 49 | |
| 50 | STATIC int /* error (0 or EFSCORRUPTED) */ |
| 51 | xfs_btree_check_lblock( |
| 52 | struct xfs_btree_cur *cur, /* btree cursor */ |
| 53 | struct xfs_btree_block *block, /* btree long form block pointer */ |
| 54 | int level, /* level of the btree block */ |
| 55 | struct xfs_buf *bp) /* buffer for block, if any */ |
| 56 | { |
| 57 | int lblock_ok; /* block passes checks */ |
| 58 | struct xfs_mount *mp; /* file system mount point */ |
| 59 | |
| 60 | mp = cur->bc_mp; |
| 61 | lblock_ok = |
| 62 | be32_to_cpu(block->bb_magic) == xfs_magics[cur->bc_btnum] && |
| 63 | be16_to_cpu(block->bb_level) == level && |
| 64 | be16_to_cpu(block->bb_numrecs) <= |
| 65 | cur->bc_ops->get_maxrecs(cur, level) && |
| 66 | block->bb_u.l.bb_leftsib && |
| 67 | (block->bb_u.l.bb_leftsib == cpu_to_be64(NULLDFSBNO) || |
| 68 | XFS_FSB_SANITY_CHECK(mp, |
| 69 | be64_to_cpu(block->bb_u.l.bb_leftsib))) && |
| 70 | block->bb_u.l.bb_rightsib && |
| 71 | (block->bb_u.l.bb_rightsib == cpu_to_be64(NULLDFSBNO) || |
| 72 | XFS_FSB_SANITY_CHECK(mp, |
| 73 | be64_to_cpu(block->bb_u.l.bb_rightsib))); |
| 74 | if (unlikely(XFS_TEST_ERROR(!lblock_ok, mp, |
| 75 | XFS_ERRTAG_BTREE_CHECK_LBLOCK, |
| 76 | XFS_RANDOM_BTREE_CHECK_LBLOCK))) { |
| 77 | if (bp) |
| 78 | trace_xfs_btree_corrupt(bp, _RET_IP_); |
| 79 | XFS_ERROR_REPORT("xfs_btree_check_lblock", XFS_ERRLEVEL_LOW, |
| 80 | mp); |
| 81 | return XFS_ERROR(EFSCORRUPTED); |
| 82 | } |
| 83 | return 0; |
| 84 | } |
| 85 | |
| 86 | STATIC int /* error (0 or EFSCORRUPTED) */ |
| 87 | xfs_btree_check_sblock( |
| 88 | struct xfs_btree_cur *cur, /* btree cursor */ |
| 89 | struct xfs_btree_block *block, /* btree short form block pointer */ |
| 90 | int level, /* level of the btree block */ |
| 91 | struct xfs_buf *bp) /* buffer containing block */ |
| 92 | { |
| 93 | struct xfs_buf *agbp; /* buffer for ag. freespace struct */ |
| 94 | struct xfs_agf *agf; /* ag. freespace structure */ |
| 95 | xfs_agblock_t agflen; /* native ag. freespace length */ |
| 96 | int sblock_ok; /* block passes checks */ |
| 97 | |
| 98 | agbp = cur->bc_private.a.agbp; |
| 99 | agf = XFS_BUF_TO_AGF(agbp); |
| 100 | agflen = be32_to_cpu(agf->agf_length); |
| 101 | sblock_ok = |
| 102 | be32_to_cpu(block->bb_magic) == xfs_magics[cur->bc_btnum] && |
| 103 | be16_to_cpu(block->bb_level) == level && |
| 104 | be16_to_cpu(block->bb_numrecs) <= |
| 105 | cur->bc_ops->get_maxrecs(cur, level) && |
| 106 | (block->bb_u.s.bb_leftsib == cpu_to_be32(NULLAGBLOCK) || |
| 107 | be32_to_cpu(block->bb_u.s.bb_leftsib) < agflen) && |
| 108 | block->bb_u.s.bb_leftsib && |
| 109 | (block->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK) || |
| 110 | be32_to_cpu(block->bb_u.s.bb_rightsib) < agflen) && |
| 111 | block->bb_u.s.bb_rightsib; |
| 112 | if (unlikely(XFS_TEST_ERROR(!sblock_ok, cur->bc_mp, |
| 113 | XFS_ERRTAG_BTREE_CHECK_SBLOCK, |
| 114 | XFS_RANDOM_BTREE_CHECK_SBLOCK))) { |
| 115 | if (bp) |
| 116 | trace_xfs_btree_corrupt(bp, _RET_IP_); |
| 117 | XFS_CORRUPTION_ERROR("xfs_btree_check_sblock", |
| 118 | XFS_ERRLEVEL_LOW, cur->bc_mp, block); |
| 119 | return XFS_ERROR(EFSCORRUPTED); |
| 120 | } |
| 121 | return 0; |
| 122 | } |
| 123 | |
| 124 | /* |
| 125 | * Debug routine: check that block header is ok. |
| 126 | */ |
| 127 | int |
| 128 | xfs_btree_check_block( |
| 129 | struct xfs_btree_cur *cur, /* btree cursor */ |
| 130 | struct xfs_btree_block *block, /* generic btree block pointer */ |
| 131 | int level, /* level of the btree block */ |
| 132 | struct xfs_buf *bp) /* buffer containing block, if any */ |
| 133 | { |
| 134 | if (cur->bc_flags & XFS_BTREE_LONG_PTRS) |
| 135 | return xfs_btree_check_lblock(cur, block, level, bp); |
| 136 | else |
| 137 | return xfs_btree_check_sblock(cur, block, level, bp); |
| 138 | } |
| 139 | |
| 140 | /* |
| 141 | * Check that (long) pointer is ok. |
| 142 | */ |
| 143 | int /* error (0 or EFSCORRUPTED) */ |
| 144 | xfs_btree_check_lptr( |
| 145 | struct xfs_btree_cur *cur, /* btree cursor */ |
| 146 | xfs_dfsbno_t bno, /* btree block disk address */ |
| 147 | int level) /* btree block level */ |
| 148 | { |
| 149 | XFS_WANT_CORRUPTED_RETURN( |
| 150 | level > 0 && |
| 151 | bno != NULLDFSBNO && |
| 152 | XFS_FSB_SANITY_CHECK(cur->bc_mp, bno)); |
| 153 | return 0; |
| 154 | } |
| 155 | |
| 156 | #ifdef DEBUG |
| 157 | /* |
| 158 | * Check that (short) pointer is ok. |
| 159 | */ |
| 160 | STATIC int /* error (0 or EFSCORRUPTED) */ |
| 161 | xfs_btree_check_sptr( |
| 162 | struct xfs_btree_cur *cur, /* btree cursor */ |
| 163 | xfs_agblock_t bno, /* btree block disk address */ |
| 164 | int level) /* btree block level */ |
| 165 | { |
| 166 | xfs_agblock_t agblocks = cur->bc_mp->m_sb.sb_agblocks; |
| 167 | |
| 168 | XFS_WANT_CORRUPTED_RETURN( |
| 169 | level > 0 && |
| 170 | bno != NULLAGBLOCK && |
| 171 | bno != 0 && |
| 172 | bno < agblocks); |
| 173 | return 0; |
| 174 | } |
| 175 | |
| 176 | /* |
| 177 | * Check that block ptr is ok. |
| 178 | */ |
| 179 | STATIC int /* error (0 or EFSCORRUPTED) */ |
| 180 | xfs_btree_check_ptr( |
| 181 | struct xfs_btree_cur *cur, /* btree cursor */ |
| 182 | union xfs_btree_ptr *ptr, /* btree block disk address */ |
| 183 | int index, /* offset from ptr to check */ |
| 184 | int level) /* btree block level */ |
| 185 | { |
| 186 | if (cur->bc_flags & XFS_BTREE_LONG_PTRS) { |
| 187 | return xfs_btree_check_lptr(cur, |
| 188 | be64_to_cpu((&ptr->l)[index]), level); |
| 189 | } else { |
| 190 | return xfs_btree_check_sptr(cur, |
| 191 | be32_to_cpu((&ptr->s)[index]), level); |
| 192 | } |
| 193 | } |
| 194 | #endif |
| 195 | |
| 196 | /* |
| 197 | * Delete the btree cursor. |
| 198 | */ |
| 199 | void |
| 200 | xfs_btree_del_cursor( |
| 201 | xfs_btree_cur_t *cur, /* btree cursor */ |
| 202 | int error) /* del because of error */ |
| 203 | { |
| 204 | int i; /* btree level */ |
| 205 | |
| 206 | /* |
| 207 | * Clear the buffer pointers, and release the buffers. |
| 208 | * If we're doing this in the face of an error, we |
| 209 | * need to make sure to inspect all of the entries |
| 210 | * in the bc_bufs array for buffers to be unlocked. |
| 211 | * This is because some of the btree code works from |
| 212 | * level n down to 0, and if we get an error along |
| 213 | * the way we won't have initialized all the entries |
| 214 | * down to 0. |
| 215 | */ |
| 216 | for (i = 0; i < cur->bc_nlevels; i++) { |
| 217 | if (cur->bc_bufs[i]) |
| 218 | xfs_trans_brelse(cur->bc_tp, cur->bc_bufs[i]); |
| 219 | else if (!error) |
| 220 | break; |
| 221 | } |
| 222 | /* |
| 223 | * Can't free a bmap cursor without having dealt with the |
| 224 | * allocated indirect blocks' accounting. |
| 225 | */ |
| 226 | ASSERT(cur->bc_btnum != XFS_BTNUM_BMAP || |
| 227 | cur->bc_private.b.allocated == 0); |
| 228 | /* |
| 229 | * Free the cursor. |
| 230 | */ |
| 231 | kmem_zone_free(xfs_btree_cur_zone, cur); |
| 232 | } |
| 233 | |
| 234 | /* |
| 235 | * Duplicate the btree cursor. |
| 236 | * Allocate a new one, copy the record, re-get the buffers. |
| 237 | */ |
| 238 | int /* error */ |
| 239 | xfs_btree_dup_cursor( |
| 240 | xfs_btree_cur_t *cur, /* input cursor */ |
| 241 | xfs_btree_cur_t **ncur) /* output cursor */ |
| 242 | { |
| 243 | xfs_buf_t *bp; /* btree block's buffer pointer */ |
| 244 | int error; /* error return value */ |
| 245 | int i; /* level number of btree block */ |
| 246 | xfs_mount_t *mp; /* mount structure for filesystem */ |
| 247 | xfs_btree_cur_t *new; /* new cursor value */ |
| 248 | xfs_trans_t *tp; /* transaction pointer, can be NULL */ |
| 249 | |
| 250 | tp = cur->bc_tp; |
| 251 | mp = cur->bc_mp; |
| 252 | |
| 253 | /* |
| 254 | * Allocate a new cursor like the old one. |
| 255 | */ |
| 256 | new = cur->bc_ops->dup_cursor(cur); |
| 257 | |
| 258 | /* |
| 259 | * Copy the record currently in the cursor. |
| 260 | */ |
| 261 | new->bc_rec = cur->bc_rec; |
| 262 | |
| 263 | /* |
| 264 | * For each level current, re-get the buffer and copy the ptr value. |
| 265 | */ |
| 266 | for (i = 0; i < new->bc_nlevels; i++) { |
| 267 | new->bc_ptrs[i] = cur->bc_ptrs[i]; |
| 268 | new->bc_ra[i] = cur->bc_ra[i]; |
| 269 | if ((bp = cur->bc_bufs[i])) { |
| 270 | if ((error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, |
| 271 | XFS_BUF_ADDR(bp), mp->m_bsize, 0, &bp))) { |
| 272 | xfs_btree_del_cursor(new, error); |
| 273 | *ncur = NULL; |
| 274 | return error; |
| 275 | } |
| 276 | new->bc_bufs[i] = bp; |
| 277 | ASSERT(!xfs_buf_geterror(bp)); |
| 278 | } else |
| 279 | new->bc_bufs[i] = NULL; |
| 280 | } |
| 281 | *ncur = new; |
| 282 | return 0; |
| 283 | } |
| 284 | |
| 285 | /* |
| 286 | * XFS btree block layout and addressing: |
| 287 | * |
| 288 | * There are two types of blocks in the btree: leaf and non-leaf blocks. |
| 289 | * |
| 290 | * The leaf record start with a header then followed by records containing |
| 291 | * the values. A non-leaf block also starts with the same header, and |
| 292 | * then first contains lookup keys followed by an equal number of pointers |
| 293 | * to the btree blocks at the previous level. |
| 294 | * |
| 295 | * +--------+-------+-------+-------+-------+-------+-------+ |
| 296 | * Leaf: | header | rec 1 | rec 2 | rec 3 | rec 4 | rec 5 | rec N | |
| 297 | * +--------+-------+-------+-------+-------+-------+-------+ |
| 298 | * |
| 299 | * +--------+-------+-------+-------+-------+-------+-------+ |
| 300 | * Non-Leaf: | header | key 1 | key 2 | key N | ptr 1 | ptr 2 | ptr N | |
| 301 | * +--------+-------+-------+-------+-------+-------+-------+ |
| 302 | * |
| 303 | * The header is called struct xfs_btree_block for reasons better left unknown |
| 304 | * and comes in different versions for short (32bit) and long (64bit) block |
| 305 | * pointers. The record and key structures are defined by the btree instances |
| 306 | * and opaque to the btree core. The block pointers are simple disk endian |
| 307 | * integers, available in a short (32bit) and long (64bit) variant. |
| 308 | * |
| 309 | * The helpers below calculate the offset of a given record, key or pointer |
| 310 | * into a btree block (xfs_btree_*_offset) or return a pointer to the given |
| 311 | * record, key or pointer (xfs_btree_*_addr). Note that all addressing |
| 312 | * inside the btree block is done using indices starting at one, not zero! |
| 313 | */ |
| 314 | |
| 315 | /* |
| 316 | * Return size of the btree block header for this btree instance. |
| 317 | */ |
| 318 | static inline size_t xfs_btree_block_len(struct xfs_btree_cur *cur) |
| 319 | { |
| 320 | return (cur->bc_flags & XFS_BTREE_LONG_PTRS) ? |
| 321 | XFS_BTREE_LBLOCK_LEN : |
| 322 | XFS_BTREE_SBLOCK_LEN; |
| 323 | } |
| 324 | |
| 325 | /* |
| 326 | * Return size of btree block pointers for this btree instance. |
| 327 | */ |
| 328 | static inline size_t xfs_btree_ptr_len(struct xfs_btree_cur *cur) |
| 329 | { |
| 330 | return (cur->bc_flags & XFS_BTREE_LONG_PTRS) ? |
| 331 | sizeof(__be64) : sizeof(__be32); |
| 332 | } |
| 333 | |
| 334 | /* |
| 335 | * Calculate offset of the n-th record in a btree block. |
| 336 | */ |
| 337 | STATIC size_t |
| 338 | xfs_btree_rec_offset( |
| 339 | struct xfs_btree_cur *cur, |
| 340 | int n) |
| 341 | { |
| 342 | return xfs_btree_block_len(cur) + |
| 343 | (n - 1) * cur->bc_ops->rec_len; |
| 344 | } |
| 345 | |
| 346 | /* |
| 347 | * Calculate offset of the n-th key in a btree block. |
| 348 | */ |
| 349 | STATIC size_t |
| 350 | xfs_btree_key_offset( |
| 351 | struct xfs_btree_cur *cur, |
| 352 | int n) |
| 353 | { |
| 354 | return xfs_btree_block_len(cur) + |
| 355 | (n - 1) * cur->bc_ops->key_len; |
| 356 | } |
| 357 | |
| 358 | /* |
| 359 | * Calculate offset of the n-th block pointer in a btree block. |
| 360 | */ |
| 361 | STATIC size_t |
| 362 | xfs_btree_ptr_offset( |
| 363 | struct xfs_btree_cur *cur, |
| 364 | int n, |
| 365 | int level) |
| 366 | { |
| 367 | return xfs_btree_block_len(cur) + |
| 368 | cur->bc_ops->get_maxrecs(cur, level) * cur->bc_ops->key_len + |
| 369 | (n - 1) * xfs_btree_ptr_len(cur); |
| 370 | } |
| 371 | |
| 372 | /* |
| 373 | * Return a pointer to the n-th record in the btree block. |
| 374 | */ |
| 375 | STATIC union xfs_btree_rec * |
| 376 | xfs_btree_rec_addr( |
| 377 | struct xfs_btree_cur *cur, |
| 378 | int n, |
| 379 | struct xfs_btree_block *block) |
| 380 | { |
| 381 | return (union xfs_btree_rec *) |
| 382 | ((char *)block + xfs_btree_rec_offset(cur, n)); |
| 383 | } |
| 384 | |
| 385 | /* |
| 386 | * Return a pointer to the n-th key in the btree block. |
| 387 | */ |
| 388 | STATIC union xfs_btree_key * |
| 389 | xfs_btree_key_addr( |
| 390 | struct xfs_btree_cur *cur, |
| 391 | int n, |
| 392 | struct xfs_btree_block *block) |
| 393 | { |
| 394 | return (union xfs_btree_key *) |
| 395 | ((char *)block + xfs_btree_key_offset(cur, n)); |
| 396 | } |
| 397 | |
| 398 | /* |
| 399 | * Return a pointer to the n-th block pointer in the btree block. |
| 400 | */ |
| 401 | STATIC union xfs_btree_ptr * |
| 402 | xfs_btree_ptr_addr( |
| 403 | struct xfs_btree_cur *cur, |
| 404 | int n, |
| 405 | struct xfs_btree_block *block) |
| 406 | { |
| 407 | int level = xfs_btree_get_level(block); |
| 408 | |
| 409 | ASSERT(block->bb_level != 0); |
| 410 | |
| 411 | return (union xfs_btree_ptr *) |
| 412 | ((char *)block + xfs_btree_ptr_offset(cur, n, level)); |
| 413 | } |
| 414 | |
| 415 | /* |
| 416 | * Get a the root block which is stored in the inode. |
| 417 | * |
| 418 | * For now this btree implementation assumes the btree root is always |
| 419 | * stored in the if_broot field of an inode fork. |
| 420 | */ |
| 421 | STATIC struct xfs_btree_block * |
| 422 | xfs_btree_get_iroot( |
| 423 | struct xfs_btree_cur *cur) |
| 424 | { |
| 425 | struct xfs_ifork *ifp; |
| 426 | |
| 427 | ifp = XFS_IFORK_PTR(cur->bc_private.b.ip, cur->bc_private.b.whichfork); |
| 428 | return (struct xfs_btree_block *)ifp->if_broot; |
| 429 | } |
| 430 | |
| 431 | /* |
| 432 | * Retrieve the block pointer from the cursor at the given level. |
| 433 | * This may be an inode btree root or from a buffer. |
| 434 | */ |
| 435 | STATIC struct xfs_btree_block * /* generic btree block pointer */ |
| 436 | xfs_btree_get_block( |
| 437 | struct xfs_btree_cur *cur, /* btree cursor */ |
| 438 | int level, /* level in btree */ |
| 439 | struct xfs_buf **bpp) /* buffer containing the block */ |
| 440 | { |
| 441 | if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) && |
| 442 | (level == cur->bc_nlevels - 1)) { |
| 443 | *bpp = NULL; |
| 444 | return xfs_btree_get_iroot(cur); |
| 445 | } |
| 446 | |
| 447 | *bpp = cur->bc_bufs[level]; |
| 448 | return XFS_BUF_TO_BLOCK(*bpp); |
| 449 | } |
| 450 | |
| 451 | /* |
| 452 | * Get a buffer for the block, return it with no data read. |
| 453 | * Long-form addressing. |
| 454 | */ |
| 455 | xfs_buf_t * /* buffer for fsbno */ |
| 456 | xfs_btree_get_bufl( |
| 457 | xfs_mount_t *mp, /* file system mount point */ |
| 458 | xfs_trans_t *tp, /* transaction pointer */ |
| 459 | xfs_fsblock_t fsbno, /* file system block number */ |
| 460 | uint lock) /* lock flags for get_buf */ |
| 461 | { |
| 462 | xfs_buf_t *bp; /* buffer pointer (return value) */ |
| 463 | xfs_daddr_t d; /* real disk block address */ |
| 464 | |
| 465 | ASSERT(fsbno != NULLFSBLOCK); |
| 466 | d = XFS_FSB_TO_DADDR(mp, fsbno); |
| 467 | bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, d, mp->m_bsize, lock); |
| 468 | ASSERT(!xfs_buf_geterror(bp)); |
| 469 | return bp; |
| 470 | } |
| 471 | |
| 472 | /* |
| 473 | * Get a buffer for the block, return it with no data read. |
| 474 | * Short-form addressing. |
| 475 | */ |
| 476 | xfs_buf_t * /* buffer for agno/agbno */ |
| 477 | xfs_btree_get_bufs( |
| 478 | xfs_mount_t *mp, /* file system mount point */ |
| 479 | xfs_trans_t *tp, /* transaction pointer */ |
| 480 | xfs_agnumber_t agno, /* allocation group number */ |
| 481 | xfs_agblock_t agbno, /* allocation group block number */ |
| 482 | uint lock) /* lock flags for get_buf */ |
| 483 | { |
| 484 | xfs_buf_t *bp; /* buffer pointer (return value) */ |
| 485 | xfs_daddr_t d; /* real disk block address */ |
| 486 | |
| 487 | ASSERT(agno != NULLAGNUMBER); |
| 488 | ASSERT(agbno != NULLAGBLOCK); |
| 489 | d = XFS_AGB_TO_DADDR(mp, agno, agbno); |
| 490 | bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, d, mp->m_bsize, lock); |
| 491 | ASSERT(!xfs_buf_geterror(bp)); |
| 492 | return bp; |
| 493 | } |
| 494 | |
| 495 | /* |
| 496 | * Check for the cursor referring to the last block at the given level. |
| 497 | */ |
| 498 | int /* 1=is last block, 0=not last block */ |
| 499 | xfs_btree_islastblock( |
| 500 | xfs_btree_cur_t *cur, /* btree cursor */ |
| 501 | int level) /* level to check */ |
| 502 | { |
| 503 | struct xfs_btree_block *block; /* generic btree block pointer */ |
| 504 | xfs_buf_t *bp; /* buffer containing block */ |
| 505 | |
| 506 | block = xfs_btree_get_block(cur, level, &bp); |
| 507 | xfs_btree_check_block(cur, block, level, bp); |
| 508 | if (cur->bc_flags & XFS_BTREE_LONG_PTRS) |
| 509 | return block->bb_u.l.bb_rightsib == cpu_to_be64(NULLDFSBNO); |
| 510 | else |
| 511 | return block->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK); |
| 512 | } |
| 513 | |
| 514 | /* |
| 515 | * Change the cursor to point to the first record at the given level. |
| 516 | * Other levels are unaffected. |
| 517 | */ |
| 518 | STATIC int /* success=1, failure=0 */ |
| 519 | xfs_btree_firstrec( |
| 520 | xfs_btree_cur_t *cur, /* btree cursor */ |
| 521 | int level) /* level to change */ |
| 522 | { |
| 523 | struct xfs_btree_block *block; /* generic btree block pointer */ |
| 524 | xfs_buf_t *bp; /* buffer containing block */ |
| 525 | |
| 526 | /* |
| 527 | * Get the block pointer for this level. |
| 528 | */ |
| 529 | block = xfs_btree_get_block(cur, level, &bp); |
| 530 | xfs_btree_check_block(cur, block, level, bp); |
| 531 | /* |
| 532 | * It's empty, there is no such record. |
| 533 | */ |
| 534 | if (!block->bb_numrecs) |
| 535 | return 0; |
| 536 | /* |
| 537 | * Set the ptr value to 1, that's the first record/key. |
| 538 | */ |
| 539 | cur->bc_ptrs[level] = 1; |
| 540 | return 1; |
| 541 | } |
| 542 | |
| 543 | /* |
| 544 | * Change the cursor to point to the last record in the current block |
| 545 | * at the given level. Other levels are unaffected. |
| 546 | */ |
| 547 | STATIC int /* success=1, failure=0 */ |
| 548 | xfs_btree_lastrec( |
| 549 | xfs_btree_cur_t *cur, /* btree cursor */ |
| 550 | int level) /* level to change */ |
| 551 | { |
| 552 | struct xfs_btree_block *block; /* generic btree block pointer */ |
| 553 | xfs_buf_t *bp; /* buffer containing block */ |
| 554 | |
| 555 | /* |
| 556 | * Get the block pointer for this level. |
| 557 | */ |
| 558 | block = xfs_btree_get_block(cur, level, &bp); |
| 559 | xfs_btree_check_block(cur, block, level, bp); |
| 560 | /* |
| 561 | * It's empty, there is no such record. |
| 562 | */ |
| 563 | if (!block->bb_numrecs) |
| 564 | return 0; |
| 565 | /* |
| 566 | * Set the ptr value to numrecs, that's the last record/key. |
| 567 | */ |
| 568 | cur->bc_ptrs[level] = be16_to_cpu(block->bb_numrecs); |
| 569 | return 1; |
| 570 | } |
| 571 | |
| 572 | /* |
| 573 | * Compute first and last byte offsets for the fields given. |
| 574 | * Interprets the offsets table, which contains struct field offsets. |
| 575 | */ |
| 576 | void |
| 577 | xfs_btree_offsets( |
| 578 | __int64_t fields, /* bitmask of fields */ |
| 579 | const short *offsets, /* table of field offsets */ |
| 580 | int nbits, /* number of bits to inspect */ |
| 581 | int *first, /* output: first byte offset */ |
| 582 | int *last) /* output: last byte offset */ |
| 583 | { |
| 584 | int i; /* current bit number */ |
| 585 | __int64_t imask; /* mask for current bit number */ |
| 586 | |
| 587 | ASSERT(fields != 0); |
| 588 | /* |
| 589 | * Find the lowest bit, so the first byte offset. |
| 590 | */ |
| 591 | for (i = 0, imask = 1LL; ; i++, imask <<= 1) { |
| 592 | if (imask & fields) { |
| 593 | *first = offsets[i]; |
| 594 | break; |
| 595 | } |
| 596 | } |
| 597 | /* |
| 598 | * Find the highest bit, so the last byte offset. |
| 599 | */ |
| 600 | for (i = nbits - 1, imask = 1LL << i; ; i--, imask >>= 1) { |
| 601 | if (imask & fields) { |
| 602 | *last = offsets[i + 1] - 1; |
| 603 | break; |
| 604 | } |
| 605 | } |
| 606 | } |
| 607 | |
| 608 | /* |
| 609 | * Get a buffer for the block, return it read in. |
| 610 | * Long-form addressing. |
| 611 | */ |
| 612 | int /* error */ |
| 613 | xfs_btree_read_bufl( |
| 614 | xfs_mount_t *mp, /* file system mount point */ |
| 615 | xfs_trans_t *tp, /* transaction pointer */ |
| 616 | xfs_fsblock_t fsbno, /* file system block number */ |
| 617 | uint lock, /* lock flags for read_buf */ |
| 618 | xfs_buf_t **bpp, /* buffer for fsbno */ |
| 619 | int refval) /* ref count value for buffer */ |
| 620 | { |
| 621 | xfs_buf_t *bp; /* return value */ |
| 622 | xfs_daddr_t d; /* real disk block address */ |
| 623 | int error; |
| 624 | |
| 625 | ASSERT(fsbno != NULLFSBLOCK); |
| 626 | d = XFS_FSB_TO_DADDR(mp, fsbno); |
| 627 | if ((error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, d, |
| 628 | mp->m_bsize, lock, &bp))) { |
| 629 | return error; |
| 630 | } |
| 631 | ASSERT(!xfs_buf_geterror(bp)); |
| 632 | if (bp) |
| 633 | xfs_buf_set_ref(bp, refval); |
| 634 | *bpp = bp; |
| 635 | return 0; |
| 636 | } |
| 637 | |
| 638 | /* |
| 639 | * Read-ahead the block, don't wait for it, don't return a buffer. |
| 640 | * Long-form addressing. |
| 641 | */ |
| 642 | /* ARGSUSED */ |
| 643 | void |
| 644 | xfs_btree_reada_bufl( |
| 645 | xfs_mount_t *mp, /* file system mount point */ |
| 646 | xfs_fsblock_t fsbno, /* file system block number */ |
| 647 | xfs_extlen_t count) /* count of filesystem blocks */ |
| 648 | { |
| 649 | xfs_daddr_t d; |
| 650 | |
| 651 | ASSERT(fsbno != NULLFSBLOCK); |
| 652 | d = XFS_FSB_TO_DADDR(mp, fsbno); |
| 653 | xfs_buf_readahead(mp->m_ddev_targp, d, mp->m_bsize * count); |
| 654 | } |
| 655 | |
| 656 | /* |
| 657 | * Read-ahead the block, don't wait for it, don't return a buffer. |
| 658 | * Short-form addressing. |
| 659 | */ |
| 660 | /* ARGSUSED */ |
| 661 | void |
| 662 | xfs_btree_reada_bufs( |
| 663 | xfs_mount_t *mp, /* file system mount point */ |
| 664 | xfs_agnumber_t agno, /* allocation group number */ |
| 665 | xfs_agblock_t agbno, /* allocation group block number */ |
| 666 | xfs_extlen_t count) /* count of filesystem blocks */ |
| 667 | { |
| 668 | xfs_daddr_t d; |
| 669 | |
| 670 | ASSERT(agno != NULLAGNUMBER); |
| 671 | ASSERT(agbno != NULLAGBLOCK); |
| 672 | d = XFS_AGB_TO_DADDR(mp, agno, agbno); |
| 673 | xfs_buf_readahead(mp->m_ddev_targp, d, mp->m_bsize * count); |
| 674 | } |
| 675 | |
| 676 | STATIC int |
| 677 | xfs_btree_readahead_lblock( |
| 678 | struct xfs_btree_cur *cur, |
| 679 | int lr, |
| 680 | struct xfs_btree_block *block) |
| 681 | { |
| 682 | int rval = 0; |
| 683 | xfs_dfsbno_t left = be64_to_cpu(block->bb_u.l.bb_leftsib); |
| 684 | xfs_dfsbno_t right = be64_to_cpu(block->bb_u.l.bb_rightsib); |
| 685 | |
| 686 | if ((lr & XFS_BTCUR_LEFTRA) && left != NULLDFSBNO) { |
| 687 | xfs_btree_reada_bufl(cur->bc_mp, left, 1); |
| 688 | rval++; |
| 689 | } |
| 690 | |
| 691 | if ((lr & XFS_BTCUR_RIGHTRA) && right != NULLDFSBNO) { |
| 692 | xfs_btree_reada_bufl(cur->bc_mp, right, 1); |
| 693 | rval++; |
| 694 | } |
| 695 | |
| 696 | return rval; |
| 697 | } |
| 698 | |
| 699 | STATIC int |
| 700 | xfs_btree_readahead_sblock( |
| 701 | struct xfs_btree_cur *cur, |
| 702 | int lr, |
| 703 | struct xfs_btree_block *block) |
| 704 | { |
| 705 | int rval = 0; |
| 706 | xfs_agblock_t left = be32_to_cpu(block->bb_u.s.bb_leftsib); |
| 707 | xfs_agblock_t right = be32_to_cpu(block->bb_u.s.bb_rightsib); |
| 708 | |
| 709 | |
| 710 | if ((lr & XFS_BTCUR_LEFTRA) && left != NULLAGBLOCK) { |
| 711 | xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.a.agno, |
| 712 | left, 1); |
| 713 | rval++; |
| 714 | } |
| 715 | |
| 716 | if ((lr & XFS_BTCUR_RIGHTRA) && right != NULLAGBLOCK) { |
| 717 | xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.a.agno, |
| 718 | right, 1); |
| 719 | rval++; |
| 720 | } |
| 721 | |
| 722 | return rval; |
| 723 | } |
| 724 | |
| 725 | /* |
| 726 | * Read-ahead btree blocks, at the given level. |
| 727 | * Bits in lr are set from XFS_BTCUR_{LEFT,RIGHT}RA. |
| 728 | */ |
| 729 | STATIC int |
| 730 | xfs_btree_readahead( |
| 731 | struct xfs_btree_cur *cur, /* btree cursor */ |
| 732 | int lev, /* level in btree */ |
| 733 | int lr) /* left/right bits */ |
| 734 | { |
| 735 | struct xfs_btree_block *block; |
| 736 | |
| 737 | /* |
| 738 | * No readahead needed if we are at the root level and the |
| 739 | * btree root is stored in the inode. |
| 740 | */ |
| 741 | if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) && |
| 742 | (lev == cur->bc_nlevels - 1)) |
| 743 | return 0; |
| 744 | |
| 745 | if ((cur->bc_ra[lev] | lr) == cur->bc_ra[lev]) |
| 746 | return 0; |
| 747 | |
| 748 | cur->bc_ra[lev] |= lr; |
| 749 | block = XFS_BUF_TO_BLOCK(cur->bc_bufs[lev]); |
| 750 | |
| 751 | if (cur->bc_flags & XFS_BTREE_LONG_PTRS) |
| 752 | return xfs_btree_readahead_lblock(cur, lr, block); |
| 753 | return xfs_btree_readahead_sblock(cur, lr, block); |
| 754 | } |
| 755 | |
| 756 | /* |
| 757 | * Set the buffer for level "lev" in the cursor to bp, releasing |
| 758 | * any previous buffer. |
| 759 | */ |
| 760 | STATIC void |
| 761 | xfs_btree_setbuf( |
| 762 | xfs_btree_cur_t *cur, /* btree cursor */ |
| 763 | int lev, /* level in btree */ |
| 764 | xfs_buf_t *bp) /* new buffer to set */ |
| 765 | { |
| 766 | struct xfs_btree_block *b; /* btree block */ |
| 767 | |
| 768 | if (cur->bc_bufs[lev]) |
| 769 | xfs_trans_brelse(cur->bc_tp, cur->bc_bufs[lev]); |
| 770 | cur->bc_bufs[lev] = bp; |
| 771 | cur->bc_ra[lev] = 0; |
| 772 | |
| 773 | b = XFS_BUF_TO_BLOCK(bp); |
| 774 | if (cur->bc_flags & XFS_BTREE_LONG_PTRS) { |
| 775 | if (b->bb_u.l.bb_leftsib == cpu_to_be64(NULLDFSBNO)) |
| 776 | cur->bc_ra[lev] |= XFS_BTCUR_LEFTRA; |
| 777 | if (b->bb_u.l.bb_rightsib == cpu_to_be64(NULLDFSBNO)) |
| 778 | cur->bc_ra[lev] |= XFS_BTCUR_RIGHTRA; |
| 779 | } else { |
| 780 | if (b->bb_u.s.bb_leftsib == cpu_to_be32(NULLAGBLOCK)) |
| 781 | cur->bc_ra[lev] |= XFS_BTCUR_LEFTRA; |
| 782 | if (b->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK)) |
| 783 | cur->bc_ra[lev] |= XFS_BTCUR_RIGHTRA; |
| 784 | } |
| 785 | } |
| 786 | |
| 787 | STATIC int |
| 788 | xfs_btree_ptr_is_null( |
| 789 | struct xfs_btree_cur *cur, |
| 790 | union xfs_btree_ptr *ptr) |
| 791 | { |
| 792 | if (cur->bc_flags & XFS_BTREE_LONG_PTRS) |
| 793 | return ptr->l == cpu_to_be64(NULLDFSBNO); |
| 794 | else |
| 795 | return ptr->s == cpu_to_be32(NULLAGBLOCK); |
| 796 | } |
| 797 | |
| 798 | STATIC void |
| 799 | xfs_btree_set_ptr_null( |
| 800 | struct xfs_btree_cur *cur, |
| 801 | union xfs_btree_ptr *ptr) |
| 802 | { |
| 803 | if (cur->bc_flags & XFS_BTREE_LONG_PTRS) |
| 804 | ptr->l = cpu_to_be64(NULLDFSBNO); |
| 805 | else |
| 806 | ptr->s = cpu_to_be32(NULLAGBLOCK); |
| 807 | } |
| 808 | |
| 809 | /* |
| 810 | * Get/set/init sibling pointers |
| 811 | */ |
| 812 | STATIC void |
| 813 | xfs_btree_get_sibling( |
| 814 | struct xfs_btree_cur *cur, |
| 815 | struct xfs_btree_block *block, |
| 816 | union xfs_btree_ptr *ptr, |
| 817 | int lr) |
| 818 | { |
| 819 | ASSERT(lr == XFS_BB_LEFTSIB || lr == XFS_BB_RIGHTSIB); |
| 820 | |
| 821 | if (cur->bc_flags & XFS_BTREE_LONG_PTRS) { |
| 822 | if (lr == XFS_BB_RIGHTSIB) |
| 823 | ptr->l = block->bb_u.l.bb_rightsib; |
| 824 | else |
| 825 | ptr->l = block->bb_u.l.bb_leftsib; |
| 826 | } else { |
| 827 | if (lr == XFS_BB_RIGHTSIB) |
| 828 | ptr->s = block->bb_u.s.bb_rightsib; |
| 829 | else |
| 830 | ptr->s = block->bb_u.s.bb_leftsib; |
| 831 | } |
| 832 | } |
| 833 | |
| 834 | STATIC void |
| 835 | xfs_btree_set_sibling( |
| 836 | struct xfs_btree_cur *cur, |
| 837 | struct xfs_btree_block *block, |
| 838 | union xfs_btree_ptr *ptr, |
| 839 | int lr) |
| 840 | { |
| 841 | ASSERT(lr == XFS_BB_LEFTSIB || lr == XFS_BB_RIGHTSIB); |
| 842 | |
| 843 | if (cur->bc_flags & XFS_BTREE_LONG_PTRS) { |
| 844 | if (lr == XFS_BB_RIGHTSIB) |
| 845 | block->bb_u.l.bb_rightsib = ptr->l; |
| 846 | else |
| 847 | block->bb_u.l.bb_leftsib = ptr->l; |
| 848 | } else { |
| 849 | if (lr == XFS_BB_RIGHTSIB) |
| 850 | block->bb_u.s.bb_rightsib = ptr->s; |
| 851 | else |
| 852 | block->bb_u.s.bb_leftsib = ptr->s; |
| 853 | } |
| 854 | } |
| 855 | |
| 856 | STATIC void |
| 857 | xfs_btree_init_block( |
| 858 | struct xfs_btree_cur *cur, |
| 859 | int level, |
| 860 | int numrecs, |
| 861 | struct xfs_btree_block *new) /* new block */ |
| 862 | { |
| 863 | new->bb_magic = cpu_to_be32(xfs_magics[cur->bc_btnum]); |
| 864 | new->bb_level = cpu_to_be16(level); |
| 865 | new->bb_numrecs = cpu_to_be16(numrecs); |
| 866 | |
| 867 | if (cur->bc_flags & XFS_BTREE_LONG_PTRS) { |
| 868 | new->bb_u.l.bb_leftsib = cpu_to_be64(NULLDFSBNO); |
| 869 | new->bb_u.l.bb_rightsib = cpu_to_be64(NULLDFSBNO); |
| 870 | } else { |
| 871 | new->bb_u.s.bb_leftsib = cpu_to_be32(NULLAGBLOCK); |
| 872 | new->bb_u.s.bb_rightsib = cpu_to_be32(NULLAGBLOCK); |
| 873 | } |
| 874 | } |
| 875 | |
| 876 | /* |
| 877 | * Return true if ptr is the last record in the btree and |
| 878 | * we need to track updateѕ to this record. The decision |
| 879 | * will be further refined in the update_lastrec method. |
| 880 | */ |
| 881 | STATIC int |
| 882 | xfs_btree_is_lastrec( |
| 883 | struct xfs_btree_cur *cur, |
| 884 | struct xfs_btree_block *block, |
| 885 | int level) |
| 886 | { |
| 887 | union xfs_btree_ptr ptr; |
| 888 | |
| 889 | if (level > 0) |
| 890 | return 0; |
| 891 | if (!(cur->bc_flags & XFS_BTREE_LASTREC_UPDATE)) |
| 892 | return 0; |
| 893 | |
| 894 | xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB); |
| 895 | if (!xfs_btree_ptr_is_null(cur, &ptr)) |
| 896 | return 0; |
| 897 | return 1; |
| 898 | } |
| 899 | |
| 900 | STATIC void |
| 901 | xfs_btree_buf_to_ptr( |
| 902 | struct xfs_btree_cur *cur, |
| 903 | struct xfs_buf *bp, |
| 904 | union xfs_btree_ptr *ptr) |
| 905 | { |
| 906 | if (cur->bc_flags & XFS_BTREE_LONG_PTRS) |
| 907 | ptr->l = cpu_to_be64(XFS_DADDR_TO_FSB(cur->bc_mp, |
| 908 | XFS_BUF_ADDR(bp))); |
| 909 | else { |
| 910 | ptr->s = cpu_to_be32(xfs_daddr_to_agbno(cur->bc_mp, |
| 911 | XFS_BUF_ADDR(bp))); |
| 912 | } |
| 913 | } |
| 914 | |
| 915 | STATIC xfs_daddr_t |
| 916 | xfs_btree_ptr_to_daddr( |
| 917 | struct xfs_btree_cur *cur, |
| 918 | union xfs_btree_ptr *ptr) |
| 919 | { |
| 920 | if (cur->bc_flags & XFS_BTREE_LONG_PTRS) { |
| 921 | ASSERT(ptr->l != cpu_to_be64(NULLDFSBNO)); |
| 922 | |
| 923 | return XFS_FSB_TO_DADDR(cur->bc_mp, be64_to_cpu(ptr->l)); |
| 924 | } else { |
| 925 | ASSERT(cur->bc_private.a.agno != NULLAGNUMBER); |
| 926 | ASSERT(ptr->s != cpu_to_be32(NULLAGBLOCK)); |
| 927 | |
| 928 | return XFS_AGB_TO_DADDR(cur->bc_mp, cur->bc_private.a.agno, |
| 929 | be32_to_cpu(ptr->s)); |
| 930 | } |
| 931 | } |
| 932 | |
| 933 | STATIC void |
| 934 | xfs_btree_set_refs( |
| 935 | struct xfs_btree_cur *cur, |
| 936 | struct xfs_buf *bp) |
| 937 | { |
| 938 | switch (cur->bc_btnum) { |
| 939 | case XFS_BTNUM_BNO: |
| 940 | case XFS_BTNUM_CNT: |
| 941 | xfs_buf_set_ref(bp, XFS_ALLOC_BTREE_REF); |
| 942 | break; |
| 943 | case XFS_BTNUM_INO: |
| 944 | xfs_buf_set_ref(bp, XFS_INO_BTREE_REF); |
| 945 | break; |
| 946 | case XFS_BTNUM_BMAP: |
| 947 | xfs_buf_set_ref(bp, XFS_BMAP_BTREE_REF); |
| 948 | break; |
| 949 | default: |
| 950 | ASSERT(0); |
| 951 | } |
| 952 | } |
| 953 | |
| 954 | STATIC int |
| 955 | xfs_btree_get_buf_block( |
| 956 | struct xfs_btree_cur *cur, |
| 957 | union xfs_btree_ptr *ptr, |
| 958 | int flags, |
| 959 | struct xfs_btree_block **block, |
| 960 | struct xfs_buf **bpp) |
| 961 | { |
| 962 | struct xfs_mount *mp = cur->bc_mp; |
| 963 | xfs_daddr_t d; |
| 964 | |
| 965 | /* need to sort out how callers deal with failures first */ |
| 966 | ASSERT(!(flags & XBF_TRYLOCK)); |
| 967 | |
| 968 | d = xfs_btree_ptr_to_daddr(cur, ptr); |
| 969 | *bpp = xfs_trans_get_buf(cur->bc_tp, mp->m_ddev_targp, d, |
| 970 | mp->m_bsize, flags); |
| 971 | |
| 972 | if (!*bpp) |
| 973 | return ENOMEM; |
| 974 | |
| 975 | *block = XFS_BUF_TO_BLOCK(*bpp); |
| 976 | return 0; |
| 977 | } |
| 978 | |
| 979 | /* |
| 980 | * Read in the buffer at the given ptr and return the buffer and |
| 981 | * the block pointer within the buffer. |
| 982 | */ |
| 983 | STATIC int |
| 984 | xfs_btree_read_buf_block( |
| 985 | struct xfs_btree_cur *cur, |
| 986 | union xfs_btree_ptr *ptr, |
| 987 | int level, |
| 988 | int flags, |
| 989 | struct xfs_btree_block **block, |
| 990 | struct xfs_buf **bpp) |
| 991 | { |
| 992 | struct xfs_mount *mp = cur->bc_mp; |
| 993 | xfs_daddr_t d; |
| 994 | int error; |
| 995 | |
| 996 | /* need to sort out how callers deal with failures first */ |
| 997 | ASSERT(!(flags & XBF_TRYLOCK)); |
| 998 | |
| 999 | d = xfs_btree_ptr_to_daddr(cur, ptr); |
| 1000 | error = xfs_trans_read_buf(mp, cur->bc_tp, mp->m_ddev_targp, d, |
| 1001 | mp->m_bsize, flags, bpp); |
| 1002 | if (error) |
| 1003 | return error; |
| 1004 | |
| 1005 | ASSERT(!xfs_buf_geterror(*bpp)); |
| 1006 | |
| 1007 | xfs_btree_set_refs(cur, *bpp); |
| 1008 | *block = XFS_BUF_TO_BLOCK(*bpp); |
| 1009 | |
| 1010 | error = xfs_btree_check_block(cur, *block, level, *bpp); |
| 1011 | if (error) |
| 1012 | xfs_trans_brelse(cur->bc_tp, *bpp); |
| 1013 | return error; |
| 1014 | } |
| 1015 | |
| 1016 | /* |
| 1017 | * Copy keys from one btree block to another. |
| 1018 | */ |
| 1019 | STATIC void |
| 1020 | xfs_btree_copy_keys( |
| 1021 | struct xfs_btree_cur *cur, |
| 1022 | union xfs_btree_key *dst_key, |
| 1023 | union xfs_btree_key *src_key, |
| 1024 | int numkeys) |
| 1025 | { |
| 1026 | ASSERT(numkeys >= 0); |
| 1027 | memcpy(dst_key, src_key, numkeys * cur->bc_ops->key_len); |
| 1028 | } |
| 1029 | |
| 1030 | /* |
| 1031 | * Copy records from one btree block to another. |
| 1032 | */ |
| 1033 | STATIC void |
| 1034 | xfs_btree_copy_recs( |
| 1035 | struct xfs_btree_cur *cur, |
| 1036 | union xfs_btree_rec *dst_rec, |
| 1037 | union xfs_btree_rec *src_rec, |
| 1038 | int numrecs) |
| 1039 | { |
| 1040 | ASSERT(numrecs >= 0); |
| 1041 | memcpy(dst_rec, src_rec, numrecs * cur->bc_ops->rec_len); |
| 1042 | } |
| 1043 | |
| 1044 | /* |
| 1045 | * Copy block pointers from one btree block to another. |
| 1046 | */ |
| 1047 | STATIC void |
| 1048 | xfs_btree_copy_ptrs( |
| 1049 | struct xfs_btree_cur *cur, |
| 1050 | union xfs_btree_ptr *dst_ptr, |
| 1051 | union xfs_btree_ptr *src_ptr, |
| 1052 | int numptrs) |
| 1053 | { |
| 1054 | ASSERT(numptrs >= 0); |
| 1055 | memcpy(dst_ptr, src_ptr, numptrs * xfs_btree_ptr_len(cur)); |
| 1056 | } |
| 1057 | |
| 1058 | /* |
| 1059 | * Shift keys one index left/right inside a single btree block. |
| 1060 | */ |
| 1061 | STATIC void |
| 1062 | xfs_btree_shift_keys( |
| 1063 | struct xfs_btree_cur *cur, |
| 1064 | union xfs_btree_key *key, |
| 1065 | int dir, |
| 1066 | int numkeys) |
| 1067 | { |
| 1068 | char *dst_key; |
| 1069 | |
| 1070 | ASSERT(numkeys >= 0); |
| 1071 | ASSERT(dir == 1 || dir == -1); |
| 1072 | |
| 1073 | dst_key = (char *)key + (dir * cur->bc_ops->key_len); |
| 1074 | memmove(dst_key, key, numkeys * cur->bc_ops->key_len); |
| 1075 | } |
| 1076 | |
| 1077 | /* |
| 1078 | * Shift records one index left/right inside a single btree block. |
| 1079 | */ |
| 1080 | STATIC void |
| 1081 | xfs_btree_shift_recs( |
| 1082 | struct xfs_btree_cur *cur, |
| 1083 | union xfs_btree_rec *rec, |
| 1084 | int dir, |
| 1085 | int numrecs) |
| 1086 | { |
| 1087 | char *dst_rec; |
| 1088 | |
| 1089 | ASSERT(numrecs >= 0); |
| 1090 | ASSERT(dir == 1 || dir == -1); |
| 1091 | |
| 1092 | dst_rec = (char *)rec + (dir * cur->bc_ops->rec_len); |
| 1093 | memmove(dst_rec, rec, numrecs * cur->bc_ops->rec_len); |
| 1094 | } |
| 1095 | |
| 1096 | /* |
| 1097 | * Shift block pointers one index left/right inside a single btree block. |
| 1098 | */ |
| 1099 | STATIC void |
| 1100 | xfs_btree_shift_ptrs( |
| 1101 | struct xfs_btree_cur *cur, |
| 1102 | union xfs_btree_ptr *ptr, |
| 1103 | int dir, |
| 1104 | int numptrs) |
| 1105 | { |
| 1106 | char *dst_ptr; |
| 1107 | |
| 1108 | ASSERT(numptrs >= 0); |
| 1109 | ASSERT(dir == 1 || dir == -1); |
| 1110 | |
| 1111 | dst_ptr = (char *)ptr + (dir * xfs_btree_ptr_len(cur)); |
| 1112 | memmove(dst_ptr, ptr, numptrs * xfs_btree_ptr_len(cur)); |
| 1113 | } |
| 1114 | |
| 1115 | /* |
| 1116 | * Log key values from the btree block. |
| 1117 | */ |
| 1118 | STATIC void |
| 1119 | xfs_btree_log_keys( |
| 1120 | struct xfs_btree_cur *cur, |
| 1121 | struct xfs_buf *bp, |
| 1122 | int first, |
| 1123 | int last) |
| 1124 | { |
| 1125 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| 1126 | XFS_BTREE_TRACE_ARGBII(cur, bp, first, last); |
| 1127 | |
| 1128 | if (bp) { |
| 1129 | xfs_trans_log_buf(cur->bc_tp, bp, |
| 1130 | xfs_btree_key_offset(cur, first), |
| 1131 | xfs_btree_key_offset(cur, last + 1) - 1); |
| 1132 | } else { |
| 1133 | xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip, |
| 1134 | xfs_ilog_fbroot(cur->bc_private.b.whichfork)); |
| 1135 | } |
| 1136 | |
| 1137 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 1138 | } |
| 1139 | |
| 1140 | /* |
| 1141 | * Log record values from the btree block. |
| 1142 | */ |
| 1143 | void |
| 1144 | xfs_btree_log_recs( |
| 1145 | struct xfs_btree_cur *cur, |
| 1146 | struct xfs_buf *bp, |
| 1147 | int first, |
| 1148 | int last) |
| 1149 | { |
| 1150 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| 1151 | XFS_BTREE_TRACE_ARGBII(cur, bp, first, last); |
| 1152 | |
| 1153 | xfs_trans_log_buf(cur->bc_tp, bp, |
| 1154 | xfs_btree_rec_offset(cur, first), |
| 1155 | xfs_btree_rec_offset(cur, last + 1) - 1); |
| 1156 | |
| 1157 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 1158 | } |
| 1159 | |
| 1160 | /* |
| 1161 | * Log block pointer fields from a btree block (nonleaf). |
| 1162 | */ |
| 1163 | STATIC void |
| 1164 | xfs_btree_log_ptrs( |
| 1165 | struct xfs_btree_cur *cur, /* btree cursor */ |
| 1166 | struct xfs_buf *bp, /* buffer containing btree block */ |
| 1167 | int first, /* index of first pointer to log */ |
| 1168 | int last) /* index of last pointer to log */ |
| 1169 | { |
| 1170 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| 1171 | XFS_BTREE_TRACE_ARGBII(cur, bp, first, last); |
| 1172 | |
| 1173 | if (bp) { |
| 1174 | struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp); |
| 1175 | int level = xfs_btree_get_level(block); |
| 1176 | |
| 1177 | xfs_trans_log_buf(cur->bc_tp, bp, |
| 1178 | xfs_btree_ptr_offset(cur, first, level), |
| 1179 | xfs_btree_ptr_offset(cur, last + 1, level) - 1); |
| 1180 | } else { |
| 1181 | xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip, |
| 1182 | xfs_ilog_fbroot(cur->bc_private.b.whichfork)); |
| 1183 | } |
| 1184 | |
| 1185 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 1186 | } |
| 1187 | |
| 1188 | /* |
| 1189 | * Log fields from a btree block header. |
| 1190 | */ |
| 1191 | void |
| 1192 | xfs_btree_log_block( |
| 1193 | struct xfs_btree_cur *cur, /* btree cursor */ |
| 1194 | struct xfs_buf *bp, /* buffer containing btree block */ |
| 1195 | int fields) /* mask of fields: XFS_BB_... */ |
| 1196 | { |
| 1197 | int first; /* first byte offset logged */ |
| 1198 | int last; /* last byte offset logged */ |
| 1199 | static const short soffsets[] = { /* table of offsets (short) */ |
| 1200 | offsetof(struct xfs_btree_block, bb_magic), |
| 1201 | offsetof(struct xfs_btree_block, bb_level), |
| 1202 | offsetof(struct xfs_btree_block, bb_numrecs), |
| 1203 | offsetof(struct xfs_btree_block, bb_u.s.bb_leftsib), |
| 1204 | offsetof(struct xfs_btree_block, bb_u.s.bb_rightsib), |
| 1205 | XFS_BTREE_SBLOCK_LEN |
| 1206 | }; |
| 1207 | static const short loffsets[] = { /* table of offsets (long) */ |
| 1208 | offsetof(struct xfs_btree_block, bb_magic), |
| 1209 | offsetof(struct xfs_btree_block, bb_level), |
| 1210 | offsetof(struct xfs_btree_block, bb_numrecs), |
| 1211 | offsetof(struct xfs_btree_block, bb_u.l.bb_leftsib), |
| 1212 | offsetof(struct xfs_btree_block, bb_u.l.bb_rightsib), |
| 1213 | XFS_BTREE_LBLOCK_LEN |
| 1214 | }; |
| 1215 | |
| 1216 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| 1217 | XFS_BTREE_TRACE_ARGBI(cur, bp, fields); |
| 1218 | |
| 1219 | if (bp) { |
| 1220 | xfs_btree_offsets(fields, |
| 1221 | (cur->bc_flags & XFS_BTREE_LONG_PTRS) ? |
| 1222 | loffsets : soffsets, |
| 1223 | XFS_BB_NUM_BITS, &first, &last); |
| 1224 | xfs_trans_log_buf(cur->bc_tp, bp, first, last); |
| 1225 | } else { |
| 1226 | xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip, |
| 1227 | xfs_ilog_fbroot(cur->bc_private.b.whichfork)); |
| 1228 | } |
| 1229 | |
| 1230 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 1231 | } |
| 1232 | |
| 1233 | /* |
| 1234 | * Increment cursor by one record at the level. |
| 1235 | * For nonzero levels the leaf-ward information is untouched. |
| 1236 | */ |
| 1237 | int /* error */ |
| 1238 | xfs_btree_increment( |
| 1239 | struct xfs_btree_cur *cur, |
| 1240 | int level, |
| 1241 | int *stat) /* success/failure */ |
| 1242 | { |
| 1243 | struct xfs_btree_block *block; |
| 1244 | union xfs_btree_ptr ptr; |
| 1245 | struct xfs_buf *bp; |
| 1246 | int error; /* error return value */ |
| 1247 | int lev; |
| 1248 | |
| 1249 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| 1250 | XFS_BTREE_TRACE_ARGI(cur, level); |
| 1251 | |
| 1252 | ASSERT(level < cur->bc_nlevels); |
| 1253 | |
| 1254 | /* Read-ahead to the right at this level. */ |
| 1255 | xfs_btree_readahead(cur, level, XFS_BTCUR_RIGHTRA); |
| 1256 | |
| 1257 | /* Get a pointer to the btree block. */ |
| 1258 | block = xfs_btree_get_block(cur, level, &bp); |
| 1259 | |
| 1260 | #ifdef DEBUG |
| 1261 | error = xfs_btree_check_block(cur, block, level, bp); |
| 1262 | if (error) |
| 1263 | goto error0; |
| 1264 | #endif |
| 1265 | |
| 1266 | /* We're done if we remain in the block after the increment. */ |
| 1267 | if (++cur->bc_ptrs[level] <= xfs_btree_get_numrecs(block)) |
| 1268 | goto out1; |
| 1269 | |
| 1270 | /* Fail if we just went off the right edge of the tree. */ |
| 1271 | xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB); |
| 1272 | if (xfs_btree_ptr_is_null(cur, &ptr)) |
| 1273 | goto out0; |
| 1274 | |
| 1275 | XFS_BTREE_STATS_INC(cur, increment); |
| 1276 | |
| 1277 | /* |
| 1278 | * March up the tree incrementing pointers. |
| 1279 | * Stop when we don't go off the right edge of a block. |
| 1280 | */ |
| 1281 | for (lev = level + 1; lev < cur->bc_nlevels; lev++) { |
| 1282 | block = xfs_btree_get_block(cur, lev, &bp); |
| 1283 | |
| 1284 | #ifdef DEBUG |
| 1285 | error = xfs_btree_check_block(cur, block, lev, bp); |
| 1286 | if (error) |
| 1287 | goto error0; |
| 1288 | #endif |
| 1289 | |
| 1290 | if (++cur->bc_ptrs[lev] <= xfs_btree_get_numrecs(block)) |
| 1291 | break; |
| 1292 | |
| 1293 | /* Read-ahead the right block for the next loop. */ |
| 1294 | xfs_btree_readahead(cur, lev, XFS_BTCUR_RIGHTRA); |
| 1295 | } |
| 1296 | |
| 1297 | /* |
| 1298 | * If we went off the root then we are either seriously |
| 1299 | * confused or have the tree root in an inode. |
| 1300 | */ |
| 1301 | if (lev == cur->bc_nlevels) { |
| 1302 | if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) |
| 1303 | goto out0; |
| 1304 | ASSERT(0); |
| 1305 | error = EFSCORRUPTED; |
| 1306 | goto error0; |
| 1307 | } |
| 1308 | ASSERT(lev < cur->bc_nlevels); |
| 1309 | |
| 1310 | /* |
| 1311 | * Now walk back down the tree, fixing up the cursor's buffer |
| 1312 | * pointers and key numbers. |
| 1313 | */ |
| 1314 | for (block = xfs_btree_get_block(cur, lev, &bp); lev > level; ) { |
| 1315 | union xfs_btree_ptr *ptrp; |
| 1316 | |
| 1317 | ptrp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[lev], block); |
| 1318 | error = xfs_btree_read_buf_block(cur, ptrp, --lev, |
| 1319 | 0, &block, &bp); |
| 1320 | if (error) |
| 1321 | goto error0; |
| 1322 | |
| 1323 | xfs_btree_setbuf(cur, lev, bp); |
| 1324 | cur->bc_ptrs[lev] = 1; |
| 1325 | } |
| 1326 | out1: |
| 1327 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 1328 | *stat = 1; |
| 1329 | return 0; |
| 1330 | |
| 1331 | out0: |
| 1332 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 1333 | *stat = 0; |
| 1334 | return 0; |
| 1335 | |
| 1336 | error0: |
| 1337 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| 1338 | return error; |
| 1339 | } |
| 1340 | |
| 1341 | /* |
| 1342 | * Decrement cursor by one record at the level. |
| 1343 | * For nonzero levels the leaf-ward information is untouched. |
| 1344 | */ |
| 1345 | int /* error */ |
| 1346 | xfs_btree_decrement( |
| 1347 | struct xfs_btree_cur *cur, |
| 1348 | int level, |
| 1349 | int *stat) /* success/failure */ |
| 1350 | { |
| 1351 | struct xfs_btree_block *block; |
| 1352 | xfs_buf_t *bp; |
| 1353 | int error; /* error return value */ |
| 1354 | int lev; |
| 1355 | union xfs_btree_ptr ptr; |
| 1356 | |
| 1357 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| 1358 | XFS_BTREE_TRACE_ARGI(cur, level); |
| 1359 | |
| 1360 | ASSERT(level < cur->bc_nlevels); |
| 1361 | |
| 1362 | /* Read-ahead to the left at this level. */ |
| 1363 | xfs_btree_readahead(cur, level, XFS_BTCUR_LEFTRA); |
| 1364 | |
| 1365 | /* We're done if we remain in the block after the decrement. */ |
| 1366 | if (--cur->bc_ptrs[level] > 0) |
| 1367 | goto out1; |
| 1368 | |
| 1369 | /* Get a pointer to the btree block. */ |
| 1370 | block = xfs_btree_get_block(cur, level, &bp); |
| 1371 | |
| 1372 | #ifdef DEBUG |
| 1373 | error = xfs_btree_check_block(cur, block, level, bp); |
| 1374 | if (error) |
| 1375 | goto error0; |
| 1376 | #endif |
| 1377 | |
| 1378 | /* Fail if we just went off the left edge of the tree. */ |
| 1379 | xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_LEFTSIB); |
| 1380 | if (xfs_btree_ptr_is_null(cur, &ptr)) |
| 1381 | goto out0; |
| 1382 | |
| 1383 | XFS_BTREE_STATS_INC(cur, decrement); |
| 1384 | |
| 1385 | /* |
| 1386 | * March up the tree decrementing pointers. |
| 1387 | * Stop when we don't go off the left edge of a block. |
| 1388 | */ |
| 1389 | for (lev = level + 1; lev < cur->bc_nlevels; lev++) { |
| 1390 | if (--cur->bc_ptrs[lev] > 0) |
| 1391 | break; |
| 1392 | /* Read-ahead the left block for the next loop. */ |
| 1393 | xfs_btree_readahead(cur, lev, XFS_BTCUR_LEFTRA); |
| 1394 | } |
| 1395 | |
| 1396 | /* |
| 1397 | * If we went off the root then we are seriously confused. |
| 1398 | * or the root of the tree is in an inode. |
| 1399 | */ |
| 1400 | if (lev == cur->bc_nlevels) { |
| 1401 | if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) |
| 1402 | goto out0; |
| 1403 | ASSERT(0); |
| 1404 | error = EFSCORRUPTED; |
| 1405 | goto error0; |
| 1406 | } |
| 1407 | ASSERT(lev < cur->bc_nlevels); |
| 1408 | |
| 1409 | /* |
| 1410 | * Now walk back down the tree, fixing up the cursor's buffer |
| 1411 | * pointers and key numbers. |
| 1412 | */ |
| 1413 | for (block = xfs_btree_get_block(cur, lev, &bp); lev > level; ) { |
| 1414 | union xfs_btree_ptr *ptrp; |
| 1415 | |
| 1416 | ptrp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[lev], block); |
| 1417 | error = xfs_btree_read_buf_block(cur, ptrp, --lev, |
| 1418 | 0, &block, &bp); |
| 1419 | if (error) |
| 1420 | goto error0; |
| 1421 | xfs_btree_setbuf(cur, lev, bp); |
| 1422 | cur->bc_ptrs[lev] = xfs_btree_get_numrecs(block); |
| 1423 | } |
| 1424 | out1: |
| 1425 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 1426 | *stat = 1; |
| 1427 | return 0; |
| 1428 | |
| 1429 | out0: |
| 1430 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 1431 | *stat = 0; |
| 1432 | return 0; |
| 1433 | |
| 1434 | error0: |
| 1435 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| 1436 | return error; |
| 1437 | } |
| 1438 | |
| 1439 | STATIC int |
| 1440 | xfs_btree_lookup_get_block( |
| 1441 | struct xfs_btree_cur *cur, /* btree cursor */ |
| 1442 | int level, /* level in the btree */ |
| 1443 | union xfs_btree_ptr *pp, /* ptr to btree block */ |
| 1444 | struct xfs_btree_block **blkp) /* return btree block */ |
| 1445 | { |
| 1446 | struct xfs_buf *bp; /* buffer pointer for btree block */ |
| 1447 | int error = 0; |
| 1448 | |
| 1449 | /* special case the root block if in an inode */ |
| 1450 | if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) && |
| 1451 | (level == cur->bc_nlevels - 1)) { |
| 1452 | *blkp = xfs_btree_get_iroot(cur); |
| 1453 | return 0; |
| 1454 | } |
| 1455 | |
| 1456 | /* |
| 1457 | * If the old buffer at this level for the disk address we are |
| 1458 | * looking for re-use it. |
| 1459 | * |
| 1460 | * Otherwise throw it away and get a new one. |
| 1461 | */ |
| 1462 | bp = cur->bc_bufs[level]; |
| 1463 | if (bp && XFS_BUF_ADDR(bp) == xfs_btree_ptr_to_daddr(cur, pp)) { |
| 1464 | *blkp = XFS_BUF_TO_BLOCK(bp); |
| 1465 | return 0; |
| 1466 | } |
| 1467 | |
| 1468 | error = xfs_btree_read_buf_block(cur, pp, level, 0, blkp, &bp); |
| 1469 | if (error) |
| 1470 | return error; |
| 1471 | |
| 1472 | xfs_btree_setbuf(cur, level, bp); |
| 1473 | return 0; |
| 1474 | } |
| 1475 | |
| 1476 | /* |
| 1477 | * Get current search key. For level 0 we don't actually have a key |
| 1478 | * structure so we make one up from the record. For all other levels |
| 1479 | * we just return the right key. |
| 1480 | */ |
| 1481 | STATIC union xfs_btree_key * |
| 1482 | xfs_lookup_get_search_key( |
| 1483 | struct xfs_btree_cur *cur, |
| 1484 | int level, |
| 1485 | int keyno, |
| 1486 | struct xfs_btree_block *block, |
| 1487 | union xfs_btree_key *kp) |
| 1488 | { |
| 1489 | if (level == 0) { |
| 1490 | cur->bc_ops->init_key_from_rec(kp, |
| 1491 | xfs_btree_rec_addr(cur, keyno, block)); |
| 1492 | return kp; |
| 1493 | } |
| 1494 | |
| 1495 | return xfs_btree_key_addr(cur, keyno, block); |
| 1496 | } |
| 1497 | |
| 1498 | /* |
| 1499 | * Lookup the record. The cursor is made to point to it, based on dir. |
| 1500 | * Return 0 if can't find any such record, 1 for success. |
| 1501 | */ |
| 1502 | int /* error */ |
| 1503 | xfs_btree_lookup( |
| 1504 | struct xfs_btree_cur *cur, /* btree cursor */ |
| 1505 | xfs_lookup_t dir, /* <=, ==, or >= */ |
| 1506 | int *stat) /* success/failure */ |
| 1507 | { |
| 1508 | struct xfs_btree_block *block; /* current btree block */ |
| 1509 | __int64_t diff; /* difference for the current key */ |
| 1510 | int error; /* error return value */ |
| 1511 | int keyno; /* current key number */ |
| 1512 | int level; /* level in the btree */ |
| 1513 | union xfs_btree_ptr *pp; /* ptr to btree block */ |
| 1514 | union xfs_btree_ptr ptr; /* ptr to btree block */ |
| 1515 | |
| 1516 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| 1517 | XFS_BTREE_TRACE_ARGI(cur, dir); |
| 1518 | |
| 1519 | XFS_BTREE_STATS_INC(cur, lookup); |
| 1520 | |
| 1521 | block = NULL; |
| 1522 | keyno = 0; |
| 1523 | |
| 1524 | /* initialise start pointer from cursor */ |
| 1525 | cur->bc_ops->init_ptr_from_cur(cur, &ptr); |
| 1526 | pp = &ptr; |
| 1527 | |
| 1528 | /* |
| 1529 | * Iterate over each level in the btree, starting at the root. |
| 1530 | * For each level above the leaves, find the key we need, based |
| 1531 | * on the lookup record, then follow the corresponding block |
| 1532 | * pointer down to the next level. |
| 1533 | */ |
| 1534 | for (level = cur->bc_nlevels - 1, diff = 1; level >= 0; level--) { |
| 1535 | /* Get the block we need to do the lookup on. */ |
| 1536 | error = xfs_btree_lookup_get_block(cur, level, pp, &block); |
| 1537 | if (error) |
| 1538 | goto error0; |
| 1539 | |
| 1540 | if (diff == 0) { |
| 1541 | /* |
| 1542 | * If we already had a key match at a higher level, we |
| 1543 | * know we need to use the first entry in this block. |
| 1544 | */ |
| 1545 | keyno = 1; |
| 1546 | } else { |
| 1547 | /* Otherwise search this block. Do a binary search. */ |
| 1548 | |
| 1549 | int high; /* high entry number */ |
| 1550 | int low; /* low entry number */ |
| 1551 | |
| 1552 | /* Set low and high entry numbers, 1-based. */ |
| 1553 | low = 1; |
| 1554 | high = xfs_btree_get_numrecs(block); |
| 1555 | if (!high) { |
| 1556 | /* Block is empty, must be an empty leaf. */ |
| 1557 | ASSERT(level == 0 && cur->bc_nlevels == 1); |
| 1558 | |
| 1559 | cur->bc_ptrs[0] = dir != XFS_LOOKUP_LE; |
| 1560 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 1561 | *stat = 0; |
| 1562 | return 0; |
| 1563 | } |
| 1564 | |
| 1565 | /* Binary search the block. */ |
| 1566 | while (low <= high) { |
| 1567 | union xfs_btree_key key; |
| 1568 | union xfs_btree_key *kp; |
| 1569 | |
| 1570 | XFS_BTREE_STATS_INC(cur, compare); |
| 1571 | |
| 1572 | /* keyno is average of low and high. */ |
| 1573 | keyno = (low + high) >> 1; |
| 1574 | |
| 1575 | /* Get current search key */ |
| 1576 | kp = xfs_lookup_get_search_key(cur, level, |
| 1577 | keyno, block, &key); |
| 1578 | |
| 1579 | /* |
| 1580 | * Compute difference to get next direction: |
| 1581 | * - less than, move right |
| 1582 | * - greater than, move left |
| 1583 | * - equal, we're done |
| 1584 | */ |
| 1585 | diff = cur->bc_ops->key_diff(cur, kp); |
| 1586 | if (diff < 0) |
| 1587 | low = keyno + 1; |
| 1588 | else if (diff > 0) |
| 1589 | high = keyno - 1; |
| 1590 | else |
| 1591 | break; |
| 1592 | } |
| 1593 | } |
| 1594 | |
| 1595 | /* |
| 1596 | * If there are more levels, set up for the next level |
| 1597 | * by getting the block number and filling in the cursor. |
| 1598 | */ |
| 1599 | if (level > 0) { |
| 1600 | /* |
| 1601 | * If we moved left, need the previous key number, |
| 1602 | * unless there isn't one. |
| 1603 | */ |
| 1604 | if (diff > 0 && --keyno < 1) |
| 1605 | keyno = 1; |
| 1606 | pp = xfs_btree_ptr_addr(cur, keyno, block); |
| 1607 | |
| 1608 | #ifdef DEBUG |
| 1609 | error = xfs_btree_check_ptr(cur, pp, 0, level); |
| 1610 | if (error) |
| 1611 | goto error0; |
| 1612 | #endif |
| 1613 | cur->bc_ptrs[level] = keyno; |
| 1614 | } |
| 1615 | } |
| 1616 | |
| 1617 | /* Done with the search. See if we need to adjust the results. */ |
| 1618 | if (dir != XFS_LOOKUP_LE && diff < 0) { |
| 1619 | keyno++; |
| 1620 | /* |
| 1621 | * If ge search and we went off the end of the block, but it's |
| 1622 | * not the last block, we're in the wrong block. |
| 1623 | */ |
| 1624 | xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB); |
| 1625 | if (dir == XFS_LOOKUP_GE && |
| 1626 | keyno > xfs_btree_get_numrecs(block) && |
| 1627 | !xfs_btree_ptr_is_null(cur, &ptr)) { |
| 1628 | int i; |
| 1629 | |
| 1630 | cur->bc_ptrs[0] = keyno; |
| 1631 | error = xfs_btree_increment(cur, 0, &i); |
| 1632 | if (error) |
| 1633 | goto error0; |
| 1634 | XFS_WANT_CORRUPTED_RETURN(i == 1); |
| 1635 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 1636 | *stat = 1; |
| 1637 | return 0; |
| 1638 | } |
| 1639 | } else if (dir == XFS_LOOKUP_LE && diff > 0) |
| 1640 | keyno--; |
| 1641 | cur->bc_ptrs[0] = keyno; |
| 1642 | |
| 1643 | /* Return if we succeeded or not. */ |
| 1644 | if (keyno == 0 || keyno > xfs_btree_get_numrecs(block)) |
| 1645 | *stat = 0; |
| 1646 | else if (dir != XFS_LOOKUP_EQ || diff == 0) |
| 1647 | *stat = 1; |
| 1648 | else |
| 1649 | *stat = 0; |
| 1650 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 1651 | return 0; |
| 1652 | |
| 1653 | error0: |
| 1654 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| 1655 | return error; |
| 1656 | } |
| 1657 | |
| 1658 | /* |
| 1659 | * Update keys at all levels from here to the root along the cursor's path. |
| 1660 | */ |
| 1661 | STATIC int |
| 1662 | xfs_btree_updkey( |
| 1663 | struct xfs_btree_cur *cur, |
| 1664 | union xfs_btree_key *keyp, |
| 1665 | int level) |
| 1666 | { |
| 1667 | struct xfs_btree_block *block; |
| 1668 | struct xfs_buf *bp; |
| 1669 | union xfs_btree_key *kp; |
| 1670 | int ptr; |
| 1671 | |
| 1672 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| 1673 | XFS_BTREE_TRACE_ARGIK(cur, level, keyp); |
| 1674 | |
| 1675 | ASSERT(!(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) || level >= 1); |
| 1676 | |
| 1677 | /* |
| 1678 | * Go up the tree from this level toward the root. |
| 1679 | * At each level, update the key value to the value input. |
| 1680 | * Stop when we reach a level where the cursor isn't pointing |
| 1681 | * at the first entry in the block. |
| 1682 | */ |
| 1683 | for (ptr = 1; ptr == 1 && level < cur->bc_nlevels; level++) { |
| 1684 | #ifdef DEBUG |
| 1685 | int error; |
| 1686 | #endif |
| 1687 | block = xfs_btree_get_block(cur, level, &bp); |
| 1688 | #ifdef DEBUG |
| 1689 | error = xfs_btree_check_block(cur, block, level, bp); |
| 1690 | if (error) { |
| 1691 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| 1692 | return error; |
| 1693 | } |
| 1694 | #endif |
| 1695 | ptr = cur->bc_ptrs[level]; |
| 1696 | kp = xfs_btree_key_addr(cur, ptr, block); |
| 1697 | xfs_btree_copy_keys(cur, kp, keyp, 1); |
| 1698 | xfs_btree_log_keys(cur, bp, ptr, ptr); |
| 1699 | } |
| 1700 | |
| 1701 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 1702 | return 0; |
| 1703 | } |
| 1704 | |
| 1705 | /* |
| 1706 | * Update the record referred to by cur to the value in the |
| 1707 | * given record. This either works (return 0) or gets an |
| 1708 | * EFSCORRUPTED error. |
| 1709 | */ |
| 1710 | int |
| 1711 | xfs_btree_update( |
| 1712 | struct xfs_btree_cur *cur, |
| 1713 | union xfs_btree_rec *rec) |
| 1714 | { |
| 1715 | struct xfs_btree_block *block; |
| 1716 | struct xfs_buf *bp; |
| 1717 | int error; |
| 1718 | int ptr; |
| 1719 | union xfs_btree_rec *rp; |
| 1720 | |
| 1721 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| 1722 | XFS_BTREE_TRACE_ARGR(cur, rec); |
| 1723 | |
| 1724 | /* Pick up the current block. */ |
| 1725 | block = xfs_btree_get_block(cur, 0, &bp); |
| 1726 | |
| 1727 | #ifdef DEBUG |
| 1728 | error = xfs_btree_check_block(cur, block, 0, bp); |
| 1729 | if (error) |
| 1730 | goto error0; |
| 1731 | #endif |
| 1732 | /* Get the address of the rec to be updated. */ |
| 1733 | ptr = cur->bc_ptrs[0]; |
| 1734 | rp = xfs_btree_rec_addr(cur, ptr, block); |
| 1735 | |
| 1736 | /* Fill in the new contents and log them. */ |
| 1737 | xfs_btree_copy_recs(cur, rp, rec, 1); |
| 1738 | xfs_btree_log_recs(cur, bp, ptr, ptr); |
| 1739 | |
| 1740 | /* |
| 1741 | * If we are tracking the last record in the tree and |
| 1742 | * we are at the far right edge of the tree, update it. |
| 1743 | */ |
| 1744 | if (xfs_btree_is_lastrec(cur, block, 0)) { |
| 1745 | cur->bc_ops->update_lastrec(cur, block, rec, |
| 1746 | ptr, LASTREC_UPDATE); |
| 1747 | } |
| 1748 | |
| 1749 | /* Updating first rec in leaf. Pass new key value up to our parent. */ |
| 1750 | if (ptr == 1) { |
| 1751 | union xfs_btree_key key; |
| 1752 | |
| 1753 | cur->bc_ops->init_key_from_rec(&key, rec); |
| 1754 | error = xfs_btree_updkey(cur, &key, 1); |
| 1755 | if (error) |
| 1756 | goto error0; |
| 1757 | } |
| 1758 | |
| 1759 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 1760 | return 0; |
| 1761 | |
| 1762 | error0: |
| 1763 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| 1764 | return error; |
| 1765 | } |
| 1766 | |
| 1767 | /* |
| 1768 | * Move 1 record left from cur/level if possible. |
| 1769 | * Update cur to reflect the new path. |
| 1770 | */ |
| 1771 | STATIC int /* error */ |
| 1772 | xfs_btree_lshift( |
| 1773 | struct xfs_btree_cur *cur, |
| 1774 | int level, |
| 1775 | int *stat) /* success/failure */ |
| 1776 | { |
| 1777 | union xfs_btree_key key; /* btree key */ |
| 1778 | struct xfs_buf *lbp; /* left buffer pointer */ |
| 1779 | struct xfs_btree_block *left; /* left btree block */ |
| 1780 | int lrecs; /* left record count */ |
| 1781 | struct xfs_buf *rbp; /* right buffer pointer */ |
| 1782 | struct xfs_btree_block *right; /* right btree block */ |
| 1783 | int rrecs; /* right record count */ |
| 1784 | union xfs_btree_ptr lptr; /* left btree pointer */ |
| 1785 | union xfs_btree_key *rkp = NULL; /* right btree key */ |
| 1786 | union xfs_btree_ptr *rpp = NULL; /* right address pointer */ |
| 1787 | union xfs_btree_rec *rrp = NULL; /* right record pointer */ |
| 1788 | int error; /* error return value */ |
| 1789 | |
| 1790 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| 1791 | XFS_BTREE_TRACE_ARGI(cur, level); |
| 1792 | |
| 1793 | if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) && |
| 1794 | level == cur->bc_nlevels - 1) |
| 1795 | goto out0; |
| 1796 | |
| 1797 | /* Set up variables for this block as "right". */ |
| 1798 | right = xfs_btree_get_block(cur, level, &rbp); |
| 1799 | |
| 1800 | #ifdef DEBUG |
| 1801 | error = xfs_btree_check_block(cur, right, level, rbp); |
| 1802 | if (error) |
| 1803 | goto error0; |
| 1804 | #endif |
| 1805 | |
| 1806 | /* If we've got no left sibling then we can't shift an entry left. */ |
| 1807 | xfs_btree_get_sibling(cur, right, &lptr, XFS_BB_LEFTSIB); |
| 1808 | if (xfs_btree_ptr_is_null(cur, &lptr)) |
| 1809 | goto out0; |
| 1810 | |
| 1811 | /* |
| 1812 | * If the cursor entry is the one that would be moved, don't |
| 1813 | * do it... it's too complicated. |
| 1814 | */ |
| 1815 | if (cur->bc_ptrs[level] <= 1) |
| 1816 | goto out0; |
| 1817 | |
| 1818 | /* Set up the left neighbor as "left". */ |
| 1819 | error = xfs_btree_read_buf_block(cur, &lptr, level, 0, &left, &lbp); |
| 1820 | if (error) |
| 1821 | goto error0; |
| 1822 | |
| 1823 | /* If it's full, it can't take another entry. */ |
| 1824 | lrecs = xfs_btree_get_numrecs(left); |
| 1825 | if (lrecs == cur->bc_ops->get_maxrecs(cur, level)) |
| 1826 | goto out0; |
| 1827 | |
| 1828 | rrecs = xfs_btree_get_numrecs(right); |
| 1829 | |
| 1830 | /* |
| 1831 | * We add one entry to the left side and remove one for the right side. |
| 1832 | * Account for it here, the changes will be updated on disk and logged |
| 1833 | * later. |
| 1834 | */ |
| 1835 | lrecs++; |
| 1836 | rrecs--; |
| 1837 | |
| 1838 | XFS_BTREE_STATS_INC(cur, lshift); |
| 1839 | XFS_BTREE_STATS_ADD(cur, moves, 1); |
| 1840 | |
| 1841 | /* |
| 1842 | * If non-leaf, copy a key and a ptr to the left block. |
| 1843 | * Log the changes to the left block. |
| 1844 | */ |
| 1845 | if (level > 0) { |
| 1846 | /* It's a non-leaf. Move keys and pointers. */ |
| 1847 | union xfs_btree_key *lkp; /* left btree key */ |
| 1848 | union xfs_btree_ptr *lpp; /* left address pointer */ |
| 1849 | |
| 1850 | lkp = xfs_btree_key_addr(cur, lrecs, left); |
| 1851 | rkp = xfs_btree_key_addr(cur, 1, right); |
| 1852 | |
| 1853 | lpp = xfs_btree_ptr_addr(cur, lrecs, left); |
| 1854 | rpp = xfs_btree_ptr_addr(cur, 1, right); |
| 1855 | #ifdef DEBUG |
| 1856 | error = xfs_btree_check_ptr(cur, rpp, 0, level); |
| 1857 | if (error) |
| 1858 | goto error0; |
| 1859 | #endif |
| 1860 | xfs_btree_copy_keys(cur, lkp, rkp, 1); |
| 1861 | xfs_btree_copy_ptrs(cur, lpp, rpp, 1); |
| 1862 | |
| 1863 | xfs_btree_log_keys(cur, lbp, lrecs, lrecs); |
| 1864 | xfs_btree_log_ptrs(cur, lbp, lrecs, lrecs); |
| 1865 | |
| 1866 | ASSERT(cur->bc_ops->keys_inorder(cur, |
| 1867 | xfs_btree_key_addr(cur, lrecs - 1, left), lkp)); |
| 1868 | } else { |
| 1869 | /* It's a leaf. Move records. */ |
| 1870 | union xfs_btree_rec *lrp; /* left record pointer */ |
| 1871 | |
| 1872 | lrp = xfs_btree_rec_addr(cur, lrecs, left); |
| 1873 | rrp = xfs_btree_rec_addr(cur, 1, right); |
| 1874 | |
| 1875 | xfs_btree_copy_recs(cur, lrp, rrp, 1); |
| 1876 | xfs_btree_log_recs(cur, lbp, lrecs, lrecs); |
| 1877 | |
| 1878 | ASSERT(cur->bc_ops->recs_inorder(cur, |
| 1879 | xfs_btree_rec_addr(cur, lrecs - 1, left), lrp)); |
| 1880 | } |
| 1881 | |
| 1882 | xfs_btree_set_numrecs(left, lrecs); |
| 1883 | xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS); |
| 1884 | |
| 1885 | xfs_btree_set_numrecs(right, rrecs); |
| 1886 | xfs_btree_log_block(cur, rbp, XFS_BB_NUMRECS); |
| 1887 | |
| 1888 | /* |
| 1889 | * Slide the contents of right down one entry. |
| 1890 | */ |
| 1891 | XFS_BTREE_STATS_ADD(cur, moves, rrecs - 1); |
| 1892 | if (level > 0) { |
| 1893 | /* It's a nonleaf. operate on keys and ptrs */ |
| 1894 | #ifdef DEBUG |
| 1895 | int i; /* loop index */ |
| 1896 | |
| 1897 | for (i = 0; i < rrecs; i++) { |
| 1898 | error = xfs_btree_check_ptr(cur, rpp, i + 1, level); |
| 1899 | if (error) |
| 1900 | goto error0; |
| 1901 | } |
| 1902 | #endif |
| 1903 | xfs_btree_shift_keys(cur, |
| 1904 | xfs_btree_key_addr(cur, 2, right), |
| 1905 | -1, rrecs); |
| 1906 | xfs_btree_shift_ptrs(cur, |
| 1907 | xfs_btree_ptr_addr(cur, 2, right), |
| 1908 | -1, rrecs); |
| 1909 | |
| 1910 | xfs_btree_log_keys(cur, rbp, 1, rrecs); |
| 1911 | xfs_btree_log_ptrs(cur, rbp, 1, rrecs); |
| 1912 | } else { |
| 1913 | /* It's a leaf. operate on records */ |
| 1914 | xfs_btree_shift_recs(cur, |
| 1915 | xfs_btree_rec_addr(cur, 2, right), |
| 1916 | -1, rrecs); |
| 1917 | xfs_btree_log_recs(cur, rbp, 1, rrecs); |
| 1918 | |
| 1919 | /* |
| 1920 | * If it's the first record in the block, we'll need a key |
| 1921 | * structure to pass up to the next level (updkey). |
| 1922 | */ |
| 1923 | cur->bc_ops->init_key_from_rec(&key, |
| 1924 | xfs_btree_rec_addr(cur, 1, right)); |
| 1925 | rkp = &key; |
| 1926 | } |
| 1927 | |
| 1928 | /* Update the parent key values of right. */ |
| 1929 | error = xfs_btree_updkey(cur, rkp, level + 1); |
| 1930 | if (error) |
| 1931 | goto error0; |
| 1932 | |
| 1933 | /* Slide the cursor value left one. */ |
| 1934 | cur->bc_ptrs[level]--; |
| 1935 | |
| 1936 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 1937 | *stat = 1; |
| 1938 | return 0; |
| 1939 | |
| 1940 | out0: |
| 1941 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 1942 | *stat = 0; |
| 1943 | return 0; |
| 1944 | |
| 1945 | error0: |
| 1946 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| 1947 | return error; |
| 1948 | } |
| 1949 | |
| 1950 | /* |
| 1951 | * Move 1 record right from cur/level if possible. |
| 1952 | * Update cur to reflect the new path. |
| 1953 | */ |
| 1954 | STATIC int /* error */ |
| 1955 | xfs_btree_rshift( |
| 1956 | struct xfs_btree_cur *cur, |
| 1957 | int level, |
| 1958 | int *stat) /* success/failure */ |
| 1959 | { |
| 1960 | union xfs_btree_key key; /* btree key */ |
| 1961 | struct xfs_buf *lbp; /* left buffer pointer */ |
| 1962 | struct xfs_btree_block *left; /* left btree block */ |
| 1963 | struct xfs_buf *rbp; /* right buffer pointer */ |
| 1964 | struct xfs_btree_block *right; /* right btree block */ |
| 1965 | struct xfs_btree_cur *tcur; /* temporary btree cursor */ |
| 1966 | union xfs_btree_ptr rptr; /* right block pointer */ |
| 1967 | union xfs_btree_key *rkp; /* right btree key */ |
| 1968 | int rrecs; /* right record count */ |
| 1969 | int lrecs; /* left record count */ |
| 1970 | int error; /* error return value */ |
| 1971 | int i; /* loop counter */ |
| 1972 | |
| 1973 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| 1974 | XFS_BTREE_TRACE_ARGI(cur, level); |
| 1975 | |
| 1976 | if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) && |
| 1977 | (level == cur->bc_nlevels - 1)) |
| 1978 | goto out0; |
| 1979 | |
| 1980 | /* Set up variables for this block as "left". */ |
| 1981 | left = xfs_btree_get_block(cur, level, &lbp); |
| 1982 | |
| 1983 | #ifdef DEBUG |
| 1984 | error = xfs_btree_check_block(cur, left, level, lbp); |
| 1985 | if (error) |
| 1986 | goto error0; |
| 1987 | #endif |
| 1988 | |
| 1989 | /* If we've got no right sibling then we can't shift an entry right. */ |
| 1990 | xfs_btree_get_sibling(cur, left, &rptr, XFS_BB_RIGHTSIB); |
| 1991 | if (xfs_btree_ptr_is_null(cur, &rptr)) |
| 1992 | goto out0; |
| 1993 | |
| 1994 | /* |
| 1995 | * If the cursor entry is the one that would be moved, don't |
| 1996 | * do it... it's too complicated. |
| 1997 | */ |
| 1998 | lrecs = xfs_btree_get_numrecs(left); |
| 1999 | if (cur->bc_ptrs[level] >= lrecs) |
| 2000 | goto out0; |
| 2001 | |
| 2002 | /* Set up the right neighbor as "right". */ |
| 2003 | error = xfs_btree_read_buf_block(cur, &rptr, level, 0, &right, &rbp); |
| 2004 | if (error) |
| 2005 | goto error0; |
| 2006 | |
| 2007 | /* If it's full, it can't take another entry. */ |
| 2008 | rrecs = xfs_btree_get_numrecs(right); |
| 2009 | if (rrecs == cur->bc_ops->get_maxrecs(cur, level)) |
| 2010 | goto out0; |
| 2011 | |
| 2012 | XFS_BTREE_STATS_INC(cur, rshift); |
| 2013 | XFS_BTREE_STATS_ADD(cur, moves, rrecs); |
| 2014 | |
| 2015 | /* |
| 2016 | * Make a hole at the start of the right neighbor block, then |
| 2017 | * copy the last left block entry to the hole. |
| 2018 | */ |
| 2019 | if (level > 0) { |
| 2020 | /* It's a nonleaf. make a hole in the keys and ptrs */ |
| 2021 | union xfs_btree_key *lkp; |
| 2022 | union xfs_btree_ptr *lpp; |
| 2023 | union xfs_btree_ptr *rpp; |
| 2024 | |
| 2025 | lkp = xfs_btree_key_addr(cur, lrecs, left); |
| 2026 | lpp = xfs_btree_ptr_addr(cur, lrecs, left); |
| 2027 | rkp = xfs_btree_key_addr(cur, 1, right); |
| 2028 | rpp = xfs_btree_ptr_addr(cur, 1, right); |
| 2029 | |
| 2030 | #ifdef DEBUG |
| 2031 | for (i = rrecs - 1; i >= 0; i--) { |
| 2032 | error = xfs_btree_check_ptr(cur, rpp, i, level); |
| 2033 | if (error) |
| 2034 | goto error0; |
| 2035 | } |
| 2036 | #endif |
| 2037 | |
| 2038 | xfs_btree_shift_keys(cur, rkp, 1, rrecs); |
| 2039 | xfs_btree_shift_ptrs(cur, rpp, 1, rrecs); |
| 2040 | |
| 2041 | #ifdef DEBUG |
| 2042 | error = xfs_btree_check_ptr(cur, lpp, 0, level); |
| 2043 | if (error) |
| 2044 | goto error0; |
| 2045 | #endif |
| 2046 | |
| 2047 | /* Now put the new data in, and log it. */ |
| 2048 | xfs_btree_copy_keys(cur, rkp, lkp, 1); |
| 2049 | xfs_btree_copy_ptrs(cur, rpp, lpp, 1); |
| 2050 | |
| 2051 | xfs_btree_log_keys(cur, rbp, 1, rrecs + 1); |
| 2052 | xfs_btree_log_ptrs(cur, rbp, 1, rrecs + 1); |
| 2053 | |
| 2054 | ASSERT(cur->bc_ops->keys_inorder(cur, rkp, |
| 2055 | xfs_btree_key_addr(cur, 2, right))); |
| 2056 | } else { |
| 2057 | /* It's a leaf. make a hole in the records */ |
| 2058 | union xfs_btree_rec *lrp; |
| 2059 | union xfs_btree_rec *rrp; |
| 2060 | |
| 2061 | lrp = xfs_btree_rec_addr(cur, lrecs, left); |
| 2062 | rrp = xfs_btree_rec_addr(cur, 1, right); |
| 2063 | |
| 2064 | xfs_btree_shift_recs(cur, rrp, 1, rrecs); |
| 2065 | |
| 2066 | /* Now put the new data in, and log it. */ |
| 2067 | xfs_btree_copy_recs(cur, rrp, lrp, 1); |
| 2068 | xfs_btree_log_recs(cur, rbp, 1, rrecs + 1); |
| 2069 | |
| 2070 | cur->bc_ops->init_key_from_rec(&key, rrp); |
| 2071 | rkp = &key; |
| 2072 | |
| 2073 | ASSERT(cur->bc_ops->recs_inorder(cur, rrp, |
| 2074 | xfs_btree_rec_addr(cur, 2, right))); |
| 2075 | } |
| 2076 | |
| 2077 | /* |
| 2078 | * Decrement and log left's numrecs, bump and log right's numrecs. |
| 2079 | */ |
| 2080 | xfs_btree_set_numrecs(left, --lrecs); |
| 2081 | xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS); |
| 2082 | |
| 2083 | xfs_btree_set_numrecs(right, ++rrecs); |
| 2084 | xfs_btree_log_block(cur, rbp, XFS_BB_NUMRECS); |
| 2085 | |
| 2086 | /* |
| 2087 | * Using a temporary cursor, update the parent key values of the |
| 2088 | * block on the right. |
| 2089 | */ |
| 2090 | error = xfs_btree_dup_cursor(cur, &tcur); |
| 2091 | if (error) |
| 2092 | goto error0; |
| 2093 | i = xfs_btree_lastrec(tcur, level); |
| 2094 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); |
| 2095 | |
| 2096 | error = xfs_btree_increment(tcur, level, &i); |
| 2097 | if (error) |
| 2098 | goto error1; |
| 2099 | |
| 2100 | error = xfs_btree_updkey(tcur, rkp, level + 1); |
| 2101 | if (error) |
| 2102 | goto error1; |
| 2103 | |
| 2104 | xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR); |
| 2105 | |
| 2106 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 2107 | *stat = 1; |
| 2108 | return 0; |
| 2109 | |
| 2110 | out0: |
| 2111 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 2112 | *stat = 0; |
| 2113 | return 0; |
| 2114 | |
| 2115 | error0: |
| 2116 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| 2117 | return error; |
| 2118 | |
| 2119 | error1: |
| 2120 | XFS_BTREE_TRACE_CURSOR(tcur, XBT_ERROR); |
| 2121 | xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR); |
| 2122 | return error; |
| 2123 | } |
| 2124 | |
| 2125 | /* |
| 2126 | * Split cur/level block in half. |
| 2127 | * Return new block number and the key to its first |
| 2128 | * record (to be inserted into parent). |
| 2129 | */ |
| 2130 | STATIC int /* error */ |
| 2131 | xfs_btree_split( |
| 2132 | struct xfs_btree_cur *cur, |
| 2133 | int level, |
| 2134 | union xfs_btree_ptr *ptrp, |
| 2135 | union xfs_btree_key *key, |
| 2136 | struct xfs_btree_cur **curp, |
| 2137 | int *stat) /* success/failure */ |
| 2138 | { |
| 2139 | union xfs_btree_ptr lptr; /* left sibling block ptr */ |
| 2140 | struct xfs_buf *lbp; /* left buffer pointer */ |
| 2141 | struct xfs_btree_block *left; /* left btree block */ |
| 2142 | union xfs_btree_ptr rptr; /* right sibling block ptr */ |
| 2143 | struct xfs_buf *rbp; /* right buffer pointer */ |
| 2144 | struct xfs_btree_block *right; /* right btree block */ |
| 2145 | union xfs_btree_ptr rrptr; /* right-right sibling ptr */ |
| 2146 | struct xfs_buf *rrbp; /* right-right buffer pointer */ |
| 2147 | struct xfs_btree_block *rrblock; /* right-right btree block */ |
| 2148 | int lrecs; |
| 2149 | int rrecs; |
| 2150 | int src_index; |
| 2151 | int error; /* error return value */ |
| 2152 | #ifdef DEBUG |
| 2153 | int i; |
| 2154 | #endif |
| 2155 | |
| 2156 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| 2157 | XFS_BTREE_TRACE_ARGIPK(cur, level, *ptrp, key); |
| 2158 | |
| 2159 | XFS_BTREE_STATS_INC(cur, split); |
| 2160 | |
| 2161 | /* Set up left block (current one). */ |
| 2162 | left = xfs_btree_get_block(cur, level, &lbp); |
| 2163 | |
| 2164 | #ifdef DEBUG |
| 2165 | error = xfs_btree_check_block(cur, left, level, lbp); |
| 2166 | if (error) |
| 2167 | goto error0; |
| 2168 | #endif |
| 2169 | |
| 2170 | xfs_btree_buf_to_ptr(cur, lbp, &lptr); |
| 2171 | |
| 2172 | /* Allocate the new block. If we can't do it, we're toast. Give up. */ |
| 2173 | error = cur->bc_ops->alloc_block(cur, &lptr, &rptr, 1, stat); |
| 2174 | if (error) |
| 2175 | goto error0; |
| 2176 | if (*stat == 0) |
| 2177 | goto out0; |
| 2178 | XFS_BTREE_STATS_INC(cur, alloc); |
| 2179 | |
| 2180 | /* Set up the new block as "right". */ |
| 2181 | error = xfs_btree_get_buf_block(cur, &rptr, 0, &right, &rbp); |
| 2182 | if (error) |
| 2183 | goto error0; |
| 2184 | |
| 2185 | /* Fill in the btree header for the new right block. */ |
| 2186 | xfs_btree_init_block(cur, xfs_btree_get_level(left), 0, right); |
| 2187 | |
| 2188 | /* |
| 2189 | * Split the entries between the old and the new block evenly. |
| 2190 | * Make sure that if there's an odd number of entries now, that |
| 2191 | * each new block will have the same number of entries. |
| 2192 | */ |
| 2193 | lrecs = xfs_btree_get_numrecs(left); |
| 2194 | rrecs = lrecs / 2; |
| 2195 | if ((lrecs & 1) && cur->bc_ptrs[level] <= rrecs + 1) |
| 2196 | rrecs++; |
| 2197 | src_index = (lrecs - rrecs + 1); |
| 2198 | |
| 2199 | XFS_BTREE_STATS_ADD(cur, moves, rrecs); |
| 2200 | |
| 2201 | /* |
| 2202 | * Copy btree block entries from the left block over to the |
| 2203 | * new block, the right. Update the right block and log the |
| 2204 | * changes. |
| 2205 | */ |
| 2206 | if (level > 0) { |
| 2207 | /* It's a non-leaf. Move keys and pointers. */ |
| 2208 | union xfs_btree_key *lkp; /* left btree key */ |
| 2209 | union xfs_btree_ptr *lpp; /* left address pointer */ |
| 2210 | union xfs_btree_key *rkp; /* right btree key */ |
| 2211 | union xfs_btree_ptr *rpp; /* right address pointer */ |
| 2212 | |
| 2213 | lkp = xfs_btree_key_addr(cur, src_index, left); |
| 2214 | lpp = xfs_btree_ptr_addr(cur, src_index, left); |
| 2215 | rkp = xfs_btree_key_addr(cur, 1, right); |
| 2216 | rpp = xfs_btree_ptr_addr(cur, 1, right); |
| 2217 | |
| 2218 | #ifdef DEBUG |
| 2219 | for (i = src_index; i < rrecs; i++) { |
| 2220 | error = xfs_btree_check_ptr(cur, lpp, i, level); |
| 2221 | if (error) |
| 2222 | goto error0; |
| 2223 | } |
| 2224 | #endif |
| 2225 | |
| 2226 | xfs_btree_copy_keys(cur, rkp, lkp, rrecs); |
| 2227 | xfs_btree_copy_ptrs(cur, rpp, lpp, rrecs); |
| 2228 | |
| 2229 | xfs_btree_log_keys(cur, rbp, 1, rrecs); |
| 2230 | xfs_btree_log_ptrs(cur, rbp, 1, rrecs); |
| 2231 | |
| 2232 | /* Grab the keys to the entries moved to the right block */ |
| 2233 | xfs_btree_copy_keys(cur, key, rkp, 1); |
| 2234 | } else { |
| 2235 | /* It's a leaf. Move records. */ |
| 2236 | union xfs_btree_rec *lrp; /* left record pointer */ |
| 2237 | union xfs_btree_rec *rrp; /* right record pointer */ |
| 2238 | |
| 2239 | lrp = xfs_btree_rec_addr(cur, src_index, left); |
| 2240 | rrp = xfs_btree_rec_addr(cur, 1, right); |
| 2241 | |
| 2242 | xfs_btree_copy_recs(cur, rrp, lrp, rrecs); |
| 2243 | xfs_btree_log_recs(cur, rbp, 1, rrecs); |
| 2244 | |
| 2245 | cur->bc_ops->init_key_from_rec(key, |
| 2246 | xfs_btree_rec_addr(cur, 1, right)); |
| 2247 | } |
| 2248 | |
| 2249 | |
| 2250 | /* |
| 2251 | * Find the left block number by looking in the buffer. |
| 2252 | * Adjust numrecs, sibling pointers. |
| 2253 | */ |
| 2254 | xfs_btree_get_sibling(cur, left, &rrptr, XFS_BB_RIGHTSIB); |
| 2255 | xfs_btree_set_sibling(cur, right, &rrptr, XFS_BB_RIGHTSIB); |
| 2256 | xfs_btree_set_sibling(cur, right, &lptr, XFS_BB_LEFTSIB); |
| 2257 | xfs_btree_set_sibling(cur, left, &rptr, XFS_BB_RIGHTSIB); |
| 2258 | |
| 2259 | lrecs -= rrecs; |
| 2260 | xfs_btree_set_numrecs(left, lrecs); |
| 2261 | xfs_btree_set_numrecs(right, xfs_btree_get_numrecs(right) + rrecs); |
| 2262 | |
| 2263 | xfs_btree_log_block(cur, rbp, XFS_BB_ALL_BITS); |
| 2264 | xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS | XFS_BB_RIGHTSIB); |
| 2265 | |
| 2266 | /* |
| 2267 | * If there's a block to the new block's right, make that block |
| 2268 | * point back to right instead of to left. |
| 2269 | */ |
| 2270 | if (!xfs_btree_ptr_is_null(cur, &rrptr)) { |
| 2271 | error = xfs_btree_read_buf_block(cur, &rrptr, level, |
| 2272 | 0, &rrblock, &rrbp); |
| 2273 | if (error) |
| 2274 | goto error0; |
| 2275 | xfs_btree_set_sibling(cur, rrblock, &rptr, XFS_BB_LEFTSIB); |
| 2276 | xfs_btree_log_block(cur, rrbp, XFS_BB_LEFTSIB); |
| 2277 | } |
| 2278 | /* |
| 2279 | * If the cursor is really in the right block, move it there. |
| 2280 | * If it's just pointing past the last entry in left, then we'll |
| 2281 | * insert there, so don't change anything in that case. |
| 2282 | */ |
| 2283 | if (cur->bc_ptrs[level] > lrecs + 1) { |
| 2284 | xfs_btree_setbuf(cur, level, rbp); |
| 2285 | cur->bc_ptrs[level] -= lrecs; |
| 2286 | } |
| 2287 | /* |
| 2288 | * If there are more levels, we'll need another cursor which refers |
| 2289 | * the right block, no matter where this cursor was. |
| 2290 | */ |
| 2291 | if (level + 1 < cur->bc_nlevels) { |
| 2292 | error = xfs_btree_dup_cursor(cur, curp); |
| 2293 | if (error) |
| 2294 | goto error0; |
| 2295 | (*curp)->bc_ptrs[level + 1]++; |
| 2296 | } |
| 2297 | *ptrp = rptr; |
| 2298 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 2299 | *stat = 1; |
| 2300 | return 0; |
| 2301 | out0: |
| 2302 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 2303 | *stat = 0; |
| 2304 | return 0; |
| 2305 | |
| 2306 | error0: |
| 2307 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| 2308 | return error; |
| 2309 | } |
| 2310 | |
| 2311 | /* |
| 2312 | * Copy the old inode root contents into a real block and make the |
| 2313 | * broot point to it. |
| 2314 | */ |
| 2315 | int /* error */ |
| 2316 | xfs_btree_new_iroot( |
| 2317 | struct xfs_btree_cur *cur, /* btree cursor */ |
| 2318 | int *logflags, /* logging flags for inode */ |
| 2319 | int *stat) /* return status - 0 fail */ |
| 2320 | { |
| 2321 | struct xfs_buf *cbp; /* buffer for cblock */ |
| 2322 | struct xfs_btree_block *block; /* btree block */ |
| 2323 | struct xfs_btree_block *cblock; /* child btree block */ |
| 2324 | union xfs_btree_key *ckp; /* child key pointer */ |
| 2325 | union xfs_btree_ptr *cpp; /* child ptr pointer */ |
| 2326 | union xfs_btree_key *kp; /* pointer to btree key */ |
| 2327 | union xfs_btree_ptr *pp; /* pointer to block addr */ |
| 2328 | union xfs_btree_ptr nptr; /* new block addr */ |
| 2329 | int level; /* btree level */ |
| 2330 | int error; /* error return code */ |
| 2331 | #ifdef DEBUG |
| 2332 | int i; /* loop counter */ |
| 2333 | #endif |
| 2334 | |
| 2335 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| 2336 | XFS_BTREE_STATS_INC(cur, newroot); |
| 2337 | |
| 2338 | ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE); |
| 2339 | |
| 2340 | level = cur->bc_nlevels - 1; |
| 2341 | |
| 2342 | block = xfs_btree_get_iroot(cur); |
| 2343 | pp = xfs_btree_ptr_addr(cur, 1, block); |
| 2344 | |
| 2345 | /* Allocate the new block. If we can't do it, we're toast. Give up. */ |
| 2346 | error = cur->bc_ops->alloc_block(cur, pp, &nptr, 1, stat); |
| 2347 | if (error) |
| 2348 | goto error0; |
| 2349 | if (*stat == 0) { |
| 2350 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 2351 | return 0; |
| 2352 | } |
| 2353 | XFS_BTREE_STATS_INC(cur, alloc); |
| 2354 | |
| 2355 | /* Copy the root into a real block. */ |
| 2356 | error = xfs_btree_get_buf_block(cur, &nptr, 0, &cblock, &cbp); |
| 2357 | if (error) |
| 2358 | goto error0; |
| 2359 | |
| 2360 | memcpy(cblock, block, xfs_btree_block_len(cur)); |
| 2361 | |
| 2362 | be16_add_cpu(&block->bb_level, 1); |
| 2363 | xfs_btree_set_numrecs(block, 1); |
| 2364 | cur->bc_nlevels++; |
| 2365 | cur->bc_ptrs[level + 1] = 1; |
| 2366 | |
| 2367 | kp = xfs_btree_key_addr(cur, 1, block); |
| 2368 | ckp = xfs_btree_key_addr(cur, 1, cblock); |
| 2369 | xfs_btree_copy_keys(cur, ckp, kp, xfs_btree_get_numrecs(cblock)); |
| 2370 | |
| 2371 | cpp = xfs_btree_ptr_addr(cur, 1, cblock); |
| 2372 | #ifdef DEBUG |
| 2373 | for (i = 0; i < be16_to_cpu(cblock->bb_numrecs); i++) { |
| 2374 | error = xfs_btree_check_ptr(cur, pp, i, level); |
| 2375 | if (error) |
| 2376 | goto error0; |
| 2377 | } |
| 2378 | #endif |
| 2379 | xfs_btree_copy_ptrs(cur, cpp, pp, xfs_btree_get_numrecs(cblock)); |
| 2380 | |
| 2381 | #ifdef DEBUG |
| 2382 | error = xfs_btree_check_ptr(cur, &nptr, 0, level); |
| 2383 | if (error) |
| 2384 | goto error0; |
| 2385 | #endif |
| 2386 | xfs_btree_copy_ptrs(cur, pp, &nptr, 1); |
| 2387 | |
| 2388 | xfs_iroot_realloc(cur->bc_private.b.ip, |
| 2389 | 1 - xfs_btree_get_numrecs(cblock), |
| 2390 | cur->bc_private.b.whichfork); |
| 2391 | |
| 2392 | xfs_btree_setbuf(cur, level, cbp); |
| 2393 | |
| 2394 | /* |
| 2395 | * Do all this logging at the end so that |
| 2396 | * the root is at the right level. |
| 2397 | */ |
| 2398 | xfs_btree_log_block(cur, cbp, XFS_BB_ALL_BITS); |
| 2399 | xfs_btree_log_keys(cur, cbp, 1, be16_to_cpu(cblock->bb_numrecs)); |
| 2400 | xfs_btree_log_ptrs(cur, cbp, 1, be16_to_cpu(cblock->bb_numrecs)); |
| 2401 | |
| 2402 | *logflags |= |
| 2403 | XFS_ILOG_CORE | xfs_ilog_fbroot(cur->bc_private.b.whichfork); |
| 2404 | *stat = 1; |
| 2405 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 2406 | return 0; |
| 2407 | error0: |
| 2408 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| 2409 | return error; |
| 2410 | } |
| 2411 | |
| 2412 | /* |
| 2413 | * Allocate a new root block, fill it in. |
| 2414 | */ |
| 2415 | STATIC int /* error */ |
| 2416 | xfs_btree_new_root( |
| 2417 | struct xfs_btree_cur *cur, /* btree cursor */ |
| 2418 | int *stat) /* success/failure */ |
| 2419 | { |
| 2420 | struct xfs_btree_block *block; /* one half of the old root block */ |
| 2421 | struct xfs_buf *bp; /* buffer containing block */ |
| 2422 | int error; /* error return value */ |
| 2423 | struct xfs_buf *lbp; /* left buffer pointer */ |
| 2424 | struct xfs_btree_block *left; /* left btree block */ |
| 2425 | struct xfs_buf *nbp; /* new (root) buffer */ |
| 2426 | struct xfs_btree_block *new; /* new (root) btree block */ |
| 2427 | int nptr; /* new value for key index, 1 or 2 */ |
| 2428 | struct xfs_buf *rbp; /* right buffer pointer */ |
| 2429 | struct xfs_btree_block *right; /* right btree block */ |
| 2430 | union xfs_btree_ptr rptr; |
| 2431 | union xfs_btree_ptr lptr; |
| 2432 | |
| 2433 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| 2434 | XFS_BTREE_STATS_INC(cur, newroot); |
| 2435 | |
| 2436 | /* initialise our start point from the cursor */ |
| 2437 | cur->bc_ops->init_ptr_from_cur(cur, &rptr); |
| 2438 | |
| 2439 | /* Allocate the new block. If we can't do it, we're toast. Give up. */ |
| 2440 | error = cur->bc_ops->alloc_block(cur, &rptr, &lptr, 1, stat); |
| 2441 | if (error) |
| 2442 | goto error0; |
| 2443 | if (*stat == 0) |
| 2444 | goto out0; |
| 2445 | XFS_BTREE_STATS_INC(cur, alloc); |
| 2446 | |
| 2447 | /* Set up the new block. */ |
| 2448 | error = xfs_btree_get_buf_block(cur, &lptr, 0, &new, &nbp); |
| 2449 | if (error) |
| 2450 | goto error0; |
| 2451 | |
| 2452 | /* Set the root in the holding structure increasing the level by 1. */ |
| 2453 | cur->bc_ops->set_root(cur, &lptr, 1); |
| 2454 | |
| 2455 | /* |
| 2456 | * At the previous root level there are now two blocks: the old root, |
| 2457 | * and the new block generated when it was split. We don't know which |
| 2458 | * one the cursor is pointing at, so we set up variables "left" and |
| 2459 | * "right" for each case. |
| 2460 | */ |
| 2461 | block = xfs_btree_get_block(cur, cur->bc_nlevels - 1, &bp); |
| 2462 | |
| 2463 | #ifdef DEBUG |
| 2464 | error = xfs_btree_check_block(cur, block, cur->bc_nlevels - 1, bp); |
| 2465 | if (error) |
| 2466 | goto error0; |
| 2467 | #endif |
| 2468 | |
| 2469 | xfs_btree_get_sibling(cur, block, &rptr, XFS_BB_RIGHTSIB); |
| 2470 | if (!xfs_btree_ptr_is_null(cur, &rptr)) { |
| 2471 | /* Our block is left, pick up the right block. */ |
| 2472 | lbp = bp; |
| 2473 | xfs_btree_buf_to_ptr(cur, lbp, &lptr); |
| 2474 | left = block; |
| 2475 | error = xfs_btree_read_buf_block(cur, &rptr, |
| 2476 | cur->bc_nlevels - 1, 0, &right, &rbp); |
| 2477 | if (error) |
| 2478 | goto error0; |
| 2479 | bp = rbp; |
| 2480 | nptr = 1; |
| 2481 | } else { |
| 2482 | /* Our block is right, pick up the left block. */ |
| 2483 | rbp = bp; |
| 2484 | xfs_btree_buf_to_ptr(cur, rbp, &rptr); |
| 2485 | right = block; |
| 2486 | xfs_btree_get_sibling(cur, right, &lptr, XFS_BB_LEFTSIB); |
| 2487 | error = xfs_btree_read_buf_block(cur, &lptr, |
| 2488 | cur->bc_nlevels - 1, 0, &left, &lbp); |
| 2489 | if (error) |
| 2490 | goto error0; |
| 2491 | bp = lbp; |
| 2492 | nptr = 2; |
| 2493 | } |
| 2494 | /* Fill in the new block's btree header and log it. */ |
| 2495 | xfs_btree_init_block(cur, cur->bc_nlevels, 2, new); |
| 2496 | xfs_btree_log_block(cur, nbp, XFS_BB_ALL_BITS); |
| 2497 | ASSERT(!xfs_btree_ptr_is_null(cur, &lptr) && |
| 2498 | !xfs_btree_ptr_is_null(cur, &rptr)); |
| 2499 | |
| 2500 | /* Fill in the key data in the new root. */ |
| 2501 | if (xfs_btree_get_level(left) > 0) { |
| 2502 | xfs_btree_copy_keys(cur, |
| 2503 | xfs_btree_key_addr(cur, 1, new), |
| 2504 | xfs_btree_key_addr(cur, 1, left), 1); |
| 2505 | xfs_btree_copy_keys(cur, |
| 2506 | xfs_btree_key_addr(cur, 2, new), |
| 2507 | xfs_btree_key_addr(cur, 1, right), 1); |
| 2508 | } else { |
| 2509 | cur->bc_ops->init_key_from_rec( |
| 2510 | xfs_btree_key_addr(cur, 1, new), |
| 2511 | xfs_btree_rec_addr(cur, 1, left)); |
| 2512 | cur->bc_ops->init_key_from_rec( |
| 2513 | xfs_btree_key_addr(cur, 2, new), |
| 2514 | xfs_btree_rec_addr(cur, 1, right)); |
| 2515 | } |
| 2516 | xfs_btree_log_keys(cur, nbp, 1, 2); |
| 2517 | |
| 2518 | /* Fill in the pointer data in the new root. */ |
| 2519 | xfs_btree_copy_ptrs(cur, |
| 2520 | xfs_btree_ptr_addr(cur, 1, new), &lptr, 1); |
| 2521 | xfs_btree_copy_ptrs(cur, |
| 2522 | xfs_btree_ptr_addr(cur, 2, new), &rptr, 1); |
| 2523 | xfs_btree_log_ptrs(cur, nbp, 1, 2); |
| 2524 | |
| 2525 | /* Fix up the cursor. */ |
| 2526 | xfs_btree_setbuf(cur, cur->bc_nlevels, nbp); |
| 2527 | cur->bc_ptrs[cur->bc_nlevels] = nptr; |
| 2528 | cur->bc_nlevels++; |
| 2529 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 2530 | *stat = 1; |
| 2531 | return 0; |
| 2532 | error0: |
| 2533 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| 2534 | return error; |
| 2535 | out0: |
| 2536 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 2537 | *stat = 0; |
| 2538 | return 0; |
| 2539 | } |
| 2540 | |
| 2541 | STATIC int |
| 2542 | xfs_btree_make_block_unfull( |
| 2543 | struct xfs_btree_cur *cur, /* btree cursor */ |
| 2544 | int level, /* btree level */ |
| 2545 | int numrecs,/* # of recs in block */ |
| 2546 | int *oindex,/* old tree index */ |
| 2547 | int *index, /* new tree index */ |
| 2548 | union xfs_btree_ptr *nptr, /* new btree ptr */ |
| 2549 | struct xfs_btree_cur **ncur, /* new btree cursor */ |
| 2550 | union xfs_btree_rec *nrec, /* new record */ |
| 2551 | int *stat) |
| 2552 | { |
| 2553 | union xfs_btree_key key; /* new btree key value */ |
| 2554 | int error = 0; |
| 2555 | |
| 2556 | if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) && |
| 2557 | level == cur->bc_nlevels - 1) { |
| 2558 | struct xfs_inode *ip = cur->bc_private.b.ip; |
| 2559 | |
| 2560 | if (numrecs < cur->bc_ops->get_dmaxrecs(cur, level)) { |
| 2561 | /* A root block that can be made bigger. */ |
| 2562 | |
| 2563 | xfs_iroot_realloc(ip, 1, cur->bc_private.b.whichfork); |
| 2564 | } else { |
| 2565 | /* A root block that needs replacing */ |
| 2566 | int logflags = 0; |
| 2567 | |
| 2568 | error = xfs_btree_new_iroot(cur, &logflags, stat); |
| 2569 | if (error || *stat == 0) |
| 2570 | return error; |
| 2571 | |
| 2572 | xfs_trans_log_inode(cur->bc_tp, ip, logflags); |
| 2573 | } |
| 2574 | |
| 2575 | return 0; |
| 2576 | } |
| 2577 | |
| 2578 | /* First, try shifting an entry to the right neighbor. */ |
| 2579 | error = xfs_btree_rshift(cur, level, stat); |
| 2580 | if (error || *stat) |
| 2581 | return error; |
| 2582 | |
| 2583 | /* Next, try shifting an entry to the left neighbor. */ |
| 2584 | error = xfs_btree_lshift(cur, level, stat); |
| 2585 | if (error) |
| 2586 | return error; |
| 2587 | |
| 2588 | if (*stat) { |
| 2589 | *oindex = *index = cur->bc_ptrs[level]; |
| 2590 | return 0; |
| 2591 | } |
| 2592 | |
| 2593 | /* |
| 2594 | * Next, try splitting the current block in half. |
| 2595 | * |
| 2596 | * If this works we have to re-set our variables because we |
| 2597 | * could be in a different block now. |
| 2598 | */ |
| 2599 | error = xfs_btree_split(cur, level, nptr, &key, ncur, stat); |
| 2600 | if (error || *stat == 0) |
| 2601 | return error; |
| 2602 | |
| 2603 | |
| 2604 | *index = cur->bc_ptrs[level]; |
| 2605 | cur->bc_ops->init_rec_from_key(&key, nrec); |
| 2606 | return 0; |
| 2607 | } |
| 2608 | |
| 2609 | /* |
| 2610 | * Insert one record/level. Return information to the caller |
| 2611 | * allowing the next level up to proceed if necessary. |
| 2612 | */ |
| 2613 | STATIC int |
| 2614 | xfs_btree_insrec( |
| 2615 | struct xfs_btree_cur *cur, /* btree cursor */ |
| 2616 | int level, /* level to insert record at */ |
| 2617 | union xfs_btree_ptr *ptrp, /* i/o: block number inserted */ |
| 2618 | union xfs_btree_rec *recp, /* i/o: record data inserted */ |
| 2619 | struct xfs_btree_cur **curp, /* output: new cursor replacing cur */ |
| 2620 | int *stat) /* success/failure */ |
| 2621 | { |
| 2622 | struct xfs_btree_block *block; /* btree block */ |
| 2623 | struct xfs_buf *bp; /* buffer for block */ |
| 2624 | union xfs_btree_key key; /* btree key */ |
| 2625 | union xfs_btree_ptr nptr; /* new block ptr */ |
| 2626 | struct xfs_btree_cur *ncur; /* new btree cursor */ |
| 2627 | union xfs_btree_rec nrec; /* new record count */ |
| 2628 | int optr; /* old key/record index */ |
| 2629 | int ptr; /* key/record index */ |
| 2630 | int numrecs;/* number of records */ |
| 2631 | int error; /* error return value */ |
| 2632 | #ifdef DEBUG |
| 2633 | int i; |
| 2634 | #endif |
| 2635 | |
| 2636 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| 2637 | XFS_BTREE_TRACE_ARGIPR(cur, level, *ptrp, recp); |
| 2638 | |
| 2639 | ncur = NULL; |
| 2640 | |
| 2641 | /* |
| 2642 | * If we have an external root pointer, and we've made it to the |
| 2643 | * root level, allocate a new root block and we're done. |
| 2644 | */ |
| 2645 | if (!(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) && |
| 2646 | (level >= cur->bc_nlevels)) { |
| 2647 | error = xfs_btree_new_root(cur, stat); |
| 2648 | xfs_btree_set_ptr_null(cur, ptrp); |
| 2649 | |
| 2650 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 2651 | return error; |
| 2652 | } |
| 2653 | |
| 2654 | /* If we're off the left edge, return failure. */ |
| 2655 | ptr = cur->bc_ptrs[level]; |
| 2656 | if (ptr == 0) { |
| 2657 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 2658 | *stat = 0; |
| 2659 | return 0; |
| 2660 | } |
| 2661 | |
| 2662 | /* Make a key out of the record data to be inserted, and save it. */ |
| 2663 | cur->bc_ops->init_key_from_rec(&key, recp); |
| 2664 | |
| 2665 | optr = ptr; |
| 2666 | |
| 2667 | XFS_BTREE_STATS_INC(cur, insrec); |
| 2668 | |
| 2669 | /* Get pointers to the btree buffer and block. */ |
| 2670 | block = xfs_btree_get_block(cur, level, &bp); |
| 2671 | numrecs = xfs_btree_get_numrecs(block); |
| 2672 | |
| 2673 | #ifdef DEBUG |
| 2674 | error = xfs_btree_check_block(cur, block, level, bp); |
| 2675 | if (error) |
| 2676 | goto error0; |
| 2677 | |
| 2678 | /* Check that the new entry is being inserted in the right place. */ |
| 2679 | if (ptr <= numrecs) { |
| 2680 | if (level == 0) { |
| 2681 | ASSERT(cur->bc_ops->recs_inorder(cur, recp, |
| 2682 | xfs_btree_rec_addr(cur, ptr, block))); |
| 2683 | } else { |
| 2684 | ASSERT(cur->bc_ops->keys_inorder(cur, &key, |
| 2685 | xfs_btree_key_addr(cur, ptr, block))); |
| 2686 | } |
| 2687 | } |
| 2688 | #endif |
| 2689 | |
| 2690 | /* |
| 2691 | * If the block is full, we can't insert the new entry until we |
| 2692 | * make the block un-full. |
| 2693 | */ |
| 2694 | xfs_btree_set_ptr_null(cur, &nptr); |
| 2695 | if (numrecs == cur->bc_ops->get_maxrecs(cur, level)) { |
| 2696 | error = xfs_btree_make_block_unfull(cur, level, numrecs, |
| 2697 | &optr, &ptr, &nptr, &ncur, &nrec, stat); |
| 2698 | if (error || *stat == 0) |
| 2699 | goto error0; |
| 2700 | } |
| 2701 | |
| 2702 | /* |
| 2703 | * The current block may have changed if the block was |
| 2704 | * previously full and we have just made space in it. |
| 2705 | */ |
| 2706 | block = xfs_btree_get_block(cur, level, &bp); |
| 2707 | numrecs = xfs_btree_get_numrecs(block); |
| 2708 | |
| 2709 | #ifdef DEBUG |
| 2710 | error = xfs_btree_check_block(cur, block, level, bp); |
| 2711 | if (error) |
| 2712 | return error; |
| 2713 | #endif |
| 2714 | |
| 2715 | /* |
| 2716 | * At this point we know there's room for our new entry in the block |
| 2717 | * we're pointing at. |
| 2718 | */ |
| 2719 | XFS_BTREE_STATS_ADD(cur, moves, numrecs - ptr + 1); |
| 2720 | |
| 2721 | if (level > 0) { |
| 2722 | /* It's a nonleaf. make a hole in the keys and ptrs */ |
| 2723 | union xfs_btree_key *kp; |
| 2724 | union xfs_btree_ptr *pp; |
| 2725 | |
| 2726 | kp = xfs_btree_key_addr(cur, ptr, block); |
| 2727 | pp = xfs_btree_ptr_addr(cur, ptr, block); |
| 2728 | |
| 2729 | #ifdef DEBUG |
| 2730 | for (i = numrecs - ptr; i >= 0; i--) { |
| 2731 | error = xfs_btree_check_ptr(cur, pp, i, level); |
| 2732 | if (error) |
| 2733 | return error; |
| 2734 | } |
| 2735 | #endif |
| 2736 | |
| 2737 | xfs_btree_shift_keys(cur, kp, 1, numrecs - ptr + 1); |
| 2738 | xfs_btree_shift_ptrs(cur, pp, 1, numrecs - ptr + 1); |
| 2739 | |
| 2740 | #ifdef DEBUG |
| 2741 | error = xfs_btree_check_ptr(cur, ptrp, 0, level); |
| 2742 | if (error) |
| 2743 | goto error0; |
| 2744 | #endif |
| 2745 | |
| 2746 | /* Now put the new data in, bump numrecs and log it. */ |
| 2747 | xfs_btree_copy_keys(cur, kp, &key, 1); |
| 2748 | xfs_btree_copy_ptrs(cur, pp, ptrp, 1); |
| 2749 | numrecs++; |
| 2750 | xfs_btree_set_numrecs(block, numrecs); |
| 2751 | xfs_btree_log_ptrs(cur, bp, ptr, numrecs); |
| 2752 | xfs_btree_log_keys(cur, bp, ptr, numrecs); |
| 2753 | #ifdef DEBUG |
| 2754 | if (ptr < numrecs) { |
| 2755 | ASSERT(cur->bc_ops->keys_inorder(cur, kp, |
| 2756 | xfs_btree_key_addr(cur, ptr + 1, block))); |
| 2757 | } |
| 2758 | #endif |
| 2759 | } else { |
| 2760 | /* It's a leaf. make a hole in the records */ |
| 2761 | union xfs_btree_rec *rp; |
| 2762 | |
| 2763 | rp = xfs_btree_rec_addr(cur, ptr, block); |
| 2764 | |
| 2765 | xfs_btree_shift_recs(cur, rp, 1, numrecs - ptr + 1); |
| 2766 | |
| 2767 | /* Now put the new data in, bump numrecs and log it. */ |
| 2768 | xfs_btree_copy_recs(cur, rp, recp, 1); |
| 2769 | xfs_btree_set_numrecs(block, ++numrecs); |
| 2770 | xfs_btree_log_recs(cur, bp, ptr, numrecs); |
| 2771 | #ifdef DEBUG |
| 2772 | if (ptr < numrecs) { |
| 2773 | ASSERT(cur->bc_ops->recs_inorder(cur, rp, |
| 2774 | xfs_btree_rec_addr(cur, ptr + 1, block))); |
| 2775 | } |
| 2776 | #endif |
| 2777 | } |
| 2778 | |
| 2779 | /* Log the new number of records in the btree header. */ |
| 2780 | xfs_btree_log_block(cur, bp, XFS_BB_NUMRECS); |
| 2781 | |
| 2782 | /* If we inserted at the start of a block, update the parents' keys. */ |
| 2783 | if (optr == 1) { |
| 2784 | error = xfs_btree_updkey(cur, &key, level + 1); |
| 2785 | if (error) |
| 2786 | goto error0; |
| 2787 | } |
| 2788 | |
| 2789 | /* |
| 2790 | * If we are tracking the last record in the tree and |
| 2791 | * we are at the far right edge of the tree, update it. |
| 2792 | */ |
| 2793 | if (xfs_btree_is_lastrec(cur, block, level)) { |
| 2794 | cur->bc_ops->update_lastrec(cur, block, recp, |
| 2795 | ptr, LASTREC_INSREC); |
| 2796 | } |
| 2797 | |
| 2798 | /* |
| 2799 | * Return the new block number, if any. |
| 2800 | * If there is one, give back a record value and a cursor too. |
| 2801 | */ |
| 2802 | *ptrp = nptr; |
| 2803 | if (!xfs_btree_ptr_is_null(cur, &nptr)) { |
| 2804 | *recp = nrec; |
| 2805 | *curp = ncur; |
| 2806 | } |
| 2807 | |
| 2808 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 2809 | *stat = 1; |
| 2810 | return 0; |
| 2811 | |
| 2812 | error0: |
| 2813 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| 2814 | return error; |
| 2815 | } |
| 2816 | |
| 2817 | /* |
| 2818 | * Insert the record at the point referenced by cur. |
| 2819 | * |
| 2820 | * A multi-level split of the tree on insert will invalidate the original |
| 2821 | * cursor. All callers of this function should assume that the cursor is |
| 2822 | * no longer valid and revalidate it. |
| 2823 | */ |
| 2824 | int |
| 2825 | xfs_btree_insert( |
| 2826 | struct xfs_btree_cur *cur, |
| 2827 | int *stat) |
| 2828 | { |
| 2829 | int error; /* error return value */ |
| 2830 | int i; /* result value, 0 for failure */ |
| 2831 | int level; /* current level number in btree */ |
| 2832 | union xfs_btree_ptr nptr; /* new block number (split result) */ |
| 2833 | struct xfs_btree_cur *ncur; /* new cursor (split result) */ |
| 2834 | struct xfs_btree_cur *pcur; /* previous level's cursor */ |
| 2835 | union xfs_btree_rec rec; /* record to insert */ |
| 2836 | |
| 2837 | level = 0; |
| 2838 | ncur = NULL; |
| 2839 | pcur = cur; |
| 2840 | |
| 2841 | xfs_btree_set_ptr_null(cur, &nptr); |
| 2842 | cur->bc_ops->init_rec_from_cur(cur, &rec); |
| 2843 | |
| 2844 | /* |
| 2845 | * Loop going up the tree, starting at the leaf level. |
| 2846 | * Stop when we don't get a split block, that must mean that |
| 2847 | * the insert is finished with this level. |
| 2848 | */ |
| 2849 | do { |
| 2850 | /* |
| 2851 | * Insert nrec/nptr into this level of the tree. |
| 2852 | * Note if we fail, nptr will be null. |
| 2853 | */ |
| 2854 | error = xfs_btree_insrec(pcur, level, &nptr, &rec, &ncur, &i); |
| 2855 | if (error) { |
| 2856 | if (pcur != cur) |
| 2857 | xfs_btree_del_cursor(pcur, XFS_BTREE_ERROR); |
| 2858 | goto error0; |
| 2859 | } |
| 2860 | |
| 2861 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); |
| 2862 | level++; |
| 2863 | |
| 2864 | /* |
| 2865 | * See if the cursor we just used is trash. |
| 2866 | * Can't trash the caller's cursor, but otherwise we should |
| 2867 | * if ncur is a new cursor or we're about to be done. |
| 2868 | */ |
| 2869 | if (pcur != cur && |
| 2870 | (ncur || xfs_btree_ptr_is_null(cur, &nptr))) { |
| 2871 | /* Save the state from the cursor before we trash it */ |
| 2872 | if (cur->bc_ops->update_cursor) |
| 2873 | cur->bc_ops->update_cursor(pcur, cur); |
| 2874 | cur->bc_nlevels = pcur->bc_nlevels; |
| 2875 | xfs_btree_del_cursor(pcur, XFS_BTREE_NOERROR); |
| 2876 | } |
| 2877 | /* If we got a new cursor, switch to it. */ |
| 2878 | if (ncur) { |
| 2879 | pcur = ncur; |
| 2880 | ncur = NULL; |
| 2881 | } |
| 2882 | } while (!xfs_btree_ptr_is_null(cur, &nptr)); |
| 2883 | |
| 2884 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 2885 | *stat = i; |
| 2886 | return 0; |
| 2887 | error0: |
| 2888 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| 2889 | return error; |
| 2890 | } |
| 2891 | |
| 2892 | /* |
| 2893 | * Try to merge a non-leaf block back into the inode root. |
| 2894 | * |
| 2895 | * Note: the killroot names comes from the fact that we're effectively |
| 2896 | * killing the old root block. But because we can't just delete the |
| 2897 | * inode we have to copy the single block it was pointing to into the |
| 2898 | * inode. |
| 2899 | */ |
| 2900 | STATIC int |
| 2901 | xfs_btree_kill_iroot( |
| 2902 | struct xfs_btree_cur *cur) |
| 2903 | { |
| 2904 | int whichfork = cur->bc_private.b.whichfork; |
| 2905 | struct xfs_inode *ip = cur->bc_private.b.ip; |
| 2906 | struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, whichfork); |
| 2907 | struct xfs_btree_block *block; |
| 2908 | struct xfs_btree_block *cblock; |
| 2909 | union xfs_btree_key *kp; |
| 2910 | union xfs_btree_key *ckp; |
| 2911 | union xfs_btree_ptr *pp; |
| 2912 | union xfs_btree_ptr *cpp; |
| 2913 | struct xfs_buf *cbp; |
| 2914 | int level; |
| 2915 | int index; |
| 2916 | int numrecs; |
| 2917 | #ifdef DEBUG |
| 2918 | union xfs_btree_ptr ptr; |
| 2919 | int i; |
| 2920 | #endif |
| 2921 | |
| 2922 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| 2923 | |
| 2924 | ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE); |
| 2925 | ASSERT(cur->bc_nlevels > 1); |
| 2926 | |
| 2927 | /* |
| 2928 | * Don't deal with the root block needs to be a leaf case. |
| 2929 | * We're just going to turn the thing back into extents anyway. |
| 2930 | */ |
| 2931 | level = cur->bc_nlevels - 1; |
| 2932 | if (level == 1) |
| 2933 | goto out0; |
| 2934 | |
| 2935 | /* |
| 2936 | * Give up if the root has multiple children. |
| 2937 | */ |
| 2938 | block = xfs_btree_get_iroot(cur); |
| 2939 | if (xfs_btree_get_numrecs(block) != 1) |
| 2940 | goto out0; |
| 2941 | |
| 2942 | cblock = xfs_btree_get_block(cur, level - 1, &cbp); |
| 2943 | numrecs = xfs_btree_get_numrecs(cblock); |
| 2944 | |
| 2945 | /* |
| 2946 | * Only do this if the next level will fit. |
| 2947 | * Then the data must be copied up to the inode, |
| 2948 | * instead of freeing the root you free the next level. |
| 2949 | */ |
| 2950 | if (numrecs > cur->bc_ops->get_dmaxrecs(cur, level)) |
| 2951 | goto out0; |
| 2952 | |
| 2953 | XFS_BTREE_STATS_INC(cur, killroot); |
| 2954 | |
| 2955 | #ifdef DEBUG |
| 2956 | xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_LEFTSIB); |
| 2957 | ASSERT(xfs_btree_ptr_is_null(cur, &ptr)); |
| 2958 | xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB); |
| 2959 | ASSERT(xfs_btree_ptr_is_null(cur, &ptr)); |
| 2960 | #endif |
| 2961 | |
| 2962 | index = numrecs - cur->bc_ops->get_maxrecs(cur, level); |
| 2963 | if (index) { |
| 2964 | xfs_iroot_realloc(cur->bc_private.b.ip, index, |
| 2965 | cur->bc_private.b.whichfork); |
| 2966 | block = ifp->if_broot; |
| 2967 | } |
| 2968 | |
| 2969 | be16_add_cpu(&block->bb_numrecs, index); |
| 2970 | ASSERT(block->bb_numrecs == cblock->bb_numrecs); |
| 2971 | |
| 2972 | kp = xfs_btree_key_addr(cur, 1, block); |
| 2973 | ckp = xfs_btree_key_addr(cur, 1, cblock); |
| 2974 | xfs_btree_copy_keys(cur, kp, ckp, numrecs); |
| 2975 | |
| 2976 | pp = xfs_btree_ptr_addr(cur, 1, block); |
| 2977 | cpp = xfs_btree_ptr_addr(cur, 1, cblock); |
| 2978 | #ifdef DEBUG |
| 2979 | for (i = 0; i < numrecs; i++) { |
| 2980 | int error; |
| 2981 | |
| 2982 | error = xfs_btree_check_ptr(cur, cpp, i, level - 1); |
| 2983 | if (error) { |
| 2984 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| 2985 | return error; |
| 2986 | } |
| 2987 | } |
| 2988 | #endif |
| 2989 | xfs_btree_copy_ptrs(cur, pp, cpp, numrecs); |
| 2990 | |
| 2991 | cur->bc_ops->free_block(cur, cbp); |
| 2992 | XFS_BTREE_STATS_INC(cur, free); |
| 2993 | |
| 2994 | cur->bc_bufs[level - 1] = NULL; |
| 2995 | be16_add_cpu(&block->bb_level, -1); |
| 2996 | xfs_trans_log_inode(cur->bc_tp, ip, |
| 2997 | XFS_ILOG_CORE | xfs_ilog_fbroot(cur->bc_private.b.whichfork)); |
| 2998 | cur->bc_nlevels--; |
| 2999 | out0: |
| 3000 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 3001 | return 0; |
| 3002 | } |
| 3003 | |
| 3004 | /* |
| 3005 | * Kill the current root node, and replace it with it's only child node. |
| 3006 | */ |
| 3007 | STATIC int |
| 3008 | xfs_btree_kill_root( |
| 3009 | struct xfs_btree_cur *cur, |
| 3010 | struct xfs_buf *bp, |
| 3011 | int level, |
| 3012 | union xfs_btree_ptr *newroot) |
| 3013 | { |
| 3014 | int error; |
| 3015 | |
| 3016 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| 3017 | XFS_BTREE_STATS_INC(cur, killroot); |
| 3018 | |
| 3019 | /* |
| 3020 | * Update the root pointer, decreasing the level by 1 and then |
| 3021 | * free the old root. |
| 3022 | */ |
| 3023 | cur->bc_ops->set_root(cur, newroot, -1); |
| 3024 | |
| 3025 | error = cur->bc_ops->free_block(cur, bp); |
| 3026 | if (error) { |
| 3027 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| 3028 | return error; |
| 3029 | } |
| 3030 | |
| 3031 | XFS_BTREE_STATS_INC(cur, free); |
| 3032 | |
| 3033 | cur->bc_bufs[level] = NULL; |
| 3034 | cur->bc_ra[level] = 0; |
| 3035 | cur->bc_nlevels--; |
| 3036 | |
| 3037 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 3038 | return 0; |
| 3039 | } |
| 3040 | |
| 3041 | STATIC int |
| 3042 | xfs_btree_dec_cursor( |
| 3043 | struct xfs_btree_cur *cur, |
| 3044 | int level, |
| 3045 | int *stat) |
| 3046 | { |
| 3047 | int error; |
| 3048 | int i; |
| 3049 | |
| 3050 | if (level > 0) { |
| 3051 | error = xfs_btree_decrement(cur, level, &i); |
| 3052 | if (error) |
| 3053 | return error; |
| 3054 | } |
| 3055 | |
| 3056 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 3057 | *stat = 1; |
| 3058 | return 0; |
| 3059 | } |
| 3060 | |
| 3061 | /* |
| 3062 | * Single level of the btree record deletion routine. |
| 3063 | * Delete record pointed to by cur/level. |
| 3064 | * Remove the record from its block then rebalance the tree. |
| 3065 | * Return 0 for error, 1 for done, 2 to go on to the next level. |
| 3066 | */ |
| 3067 | STATIC int /* error */ |
| 3068 | xfs_btree_delrec( |
| 3069 | struct xfs_btree_cur *cur, /* btree cursor */ |
| 3070 | int level, /* level removing record from */ |
| 3071 | int *stat) /* fail/done/go-on */ |
| 3072 | { |
| 3073 | struct xfs_btree_block *block; /* btree block */ |
| 3074 | union xfs_btree_ptr cptr; /* current block ptr */ |
| 3075 | struct xfs_buf *bp; /* buffer for block */ |
| 3076 | int error; /* error return value */ |
| 3077 | int i; /* loop counter */ |
| 3078 | union xfs_btree_key key; /* storage for keyp */ |
| 3079 | union xfs_btree_key *keyp = &key; /* passed to the next level */ |
| 3080 | union xfs_btree_ptr lptr; /* left sibling block ptr */ |
| 3081 | struct xfs_buf *lbp; /* left buffer pointer */ |
| 3082 | struct xfs_btree_block *left; /* left btree block */ |
| 3083 | int lrecs = 0; /* left record count */ |
| 3084 | int ptr; /* key/record index */ |
| 3085 | union xfs_btree_ptr rptr; /* right sibling block ptr */ |
| 3086 | struct xfs_buf *rbp; /* right buffer pointer */ |
| 3087 | struct xfs_btree_block *right; /* right btree block */ |
| 3088 | struct xfs_btree_block *rrblock; /* right-right btree block */ |
| 3089 | struct xfs_buf *rrbp; /* right-right buffer pointer */ |
| 3090 | int rrecs = 0; /* right record count */ |
| 3091 | struct xfs_btree_cur *tcur; /* temporary btree cursor */ |
| 3092 | int numrecs; /* temporary numrec count */ |
| 3093 | |
| 3094 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| 3095 | XFS_BTREE_TRACE_ARGI(cur, level); |
| 3096 | |
| 3097 | tcur = NULL; |
| 3098 | |
| 3099 | /* Get the index of the entry being deleted, check for nothing there. */ |
| 3100 | ptr = cur->bc_ptrs[level]; |
| 3101 | if (ptr == 0) { |
| 3102 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 3103 | *stat = 0; |
| 3104 | return 0; |
| 3105 | } |
| 3106 | |
| 3107 | /* Get the buffer & block containing the record or key/ptr. */ |
| 3108 | block = xfs_btree_get_block(cur, level, &bp); |
| 3109 | numrecs = xfs_btree_get_numrecs(block); |
| 3110 | |
| 3111 | #ifdef DEBUG |
| 3112 | error = xfs_btree_check_block(cur, block, level, bp); |
| 3113 | if (error) |
| 3114 | goto error0; |
| 3115 | #endif |
| 3116 | |
| 3117 | /* Fail if we're off the end of the block. */ |
| 3118 | if (ptr > numrecs) { |
| 3119 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 3120 | *stat = 0; |
| 3121 | return 0; |
| 3122 | } |
| 3123 | |
| 3124 | XFS_BTREE_STATS_INC(cur, delrec); |
| 3125 | XFS_BTREE_STATS_ADD(cur, moves, numrecs - ptr); |
| 3126 | |
| 3127 | /* Excise the entries being deleted. */ |
| 3128 | if (level > 0) { |
| 3129 | /* It's a nonleaf. operate on keys and ptrs */ |
| 3130 | union xfs_btree_key *lkp; |
| 3131 | union xfs_btree_ptr *lpp; |
| 3132 | |
| 3133 | lkp = xfs_btree_key_addr(cur, ptr + 1, block); |
| 3134 | lpp = xfs_btree_ptr_addr(cur, ptr + 1, block); |
| 3135 | |
| 3136 | #ifdef DEBUG |
| 3137 | for (i = 0; i < numrecs - ptr; i++) { |
| 3138 | error = xfs_btree_check_ptr(cur, lpp, i, level); |
| 3139 | if (error) |
| 3140 | goto error0; |
| 3141 | } |
| 3142 | #endif |
| 3143 | |
| 3144 | if (ptr < numrecs) { |
| 3145 | xfs_btree_shift_keys(cur, lkp, -1, numrecs - ptr); |
| 3146 | xfs_btree_shift_ptrs(cur, lpp, -1, numrecs - ptr); |
| 3147 | xfs_btree_log_keys(cur, bp, ptr, numrecs - 1); |
| 3148 | xfs_btree_log_ptrs(cur, bp, ptr, numrecs - 1); |
| 3149 | } |
| 3150 | |
| 3151 | /* |
| 3152 | * If it's the first record in the block, we'll need to pass a |
| 3153 | * key up to the next level (updkey). |
| 3154 | */ |
| 3155 | if (ptr == 1) |
| 3156 | keyp = xfs_btree_key_addr(cur, 1, block); |
| 3157 | } else { |
| 3158 | /* It's a leaf. operate on records */ |
| 3159 | if (ptr < numrecs) { |
| 3160 | xfs_btree_shift_recs(cur, |
| 3161 | xfs_btree_rec_addr(cur, ptr + 1, block), |
| 3162 | -1, numrecs - ptr); |
| 3163 | xfs_btree_log_recs(cur, bp, ptr, numrecs - 1); |
| 3164 | } |
| 3165 | |
| 3166 | /* |
| 3167 | * If it's the first record in the block, we'll need a key |
| 3168 | * structure to pass up to the next level (updkey). |
| 3169 | */ |
| 3170 | if (ptr == 1) { |
| 3171 | cur->bc_ops->init_key_from_rec(&key, |
| 3172 | xfs_btree_rec_addr(cur, 1, block)); |
| 3173 | keyp = &key; |
| 3174 | } |
| 3175 | } |
| 3176 | |
| 3177 | /* |
| 3178 | * Decrement and log the number of entries in the block. |
| 3179 | */ |
| 3180 | xfs_btree_set_numrecs(block, --numrecs); |
| 3181 | xfs_btree_log_block(cur, bp, XFS_BB_NUMRECS); |
| 3182 | |
| 3183 | /* |
| 3184 | * If we are tracking the last record in the tree and |
| 3185 | * we are at the far right edge of the tree, update it. |
| 3186 | */ |
| 3187 | if (xfs_btree_is_lastrec(cur, block, level)) { |
| 3188 | cur->bc_ops->update_lastrec(cur, block, NULL, |
| 3189 | ptr, LASTREC_DELREC); |
| 3190 | } |
| 3191 | |
| 3192 | /* |
| 3193 | * We're at the root level. First, shrink the root block in-memory. |
| 3194 | * Try to get rid of the next level down. If we can't then there's |
| 3195 | * nothing left to do. |
| 3196 | */ |
| 3197 | if (level == cur->bc_nlevels - 1) { |
| 3198 | if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) { |
| 3199 | xfs_iroot_realloc(cur->bc_private.b.ip, -1, |
| 3200 | cur->bc_private.b.whichfork); |
| 3201 | |
| 3202 | error = xfs_btree_kill_iroot(cur); |
| 3203 | if (error) |
| 3204 | goto error0; |
| 3205 | |
| 3206 | error = xfs_btree_dec_cursor(cur, level, stat); |
| 3207 | if (error) |
| 3208 | goto error0; |
| 3209 | *stat = 1; |
| 3210 | return 0; |
| 3211 | } |
| 3212 | |
| 3213 | /* |
| 3214 | * If this is the root level, and there's only one entry left, |
| 3215 | * and it's NOT the leaf level, then we can get rid of this |
| 3216 | * level. |
| 3217 | */ |
| 3218 | if (numrecs == 1 && level > 0) { |
| 3219 | union xfs_btree_ptr *pp; |
| 3220 | /* |
| 3221 | * pp is still set to the first pointer in the block. |
| 3222 | * Make it the new root of the btree. |
| 3223 | */ |
| 3224 | pp = xfs_btree_ptr_addr(cur, 1, block); |
| 3225 | error = xfs_btree_kill_root(cur, bp, level, pp); |
| 3226 | if (error) |
| 3227 | goto error0; |
| 3228 | } else if (level > 0) { |
| 3229 | error = xfs_btree_dec_cursor(cur, level, stat); |
| 3230 | if (error) |
| 3231 | goto error0; |
| 3232 | } |
| 3233 | *stat = 1; |
| 3234 | return 0; |
| 3235 | } |
| 3236 | |
| 3237 | /* |
| 3238 | * If we deleted the leftmost entry in the block, update the |
| 3239 | * key values above us in the tree. |
| 3240 | */ |
| 3241 | if (ptr == 1) { |
| 3242 | error = xfs_btree_updkey(cur, keyp, level + 1); |
| 3243 | if (error) |
| 3244 | goto error0; |
| 3245 | } |
| 3246 | |
| 3247 | /* |
| 3248 | * If the number of records remaining in the block is at least |
| 3249 | * the minimum, we're done. |
| 3250 | */ |
| 3251 | if (numrecs >= cur->bc_ops->get_minrecs(cur, level)) { |
| 3252 | error = xfs_btree_dec_cursor(cur, level, stat); |
| 3253 | if (error) |
| 3254 | goto error0; |
| 3255 | return 0; |
| 3256 | } |
| 3257 | |
| 3258 | /* |
| 3259 | * Otherwise, we have to move some records around to keep the |
| 3260 | * tree balanced. Look at the left and right sibling blocks to |
| 3261 | * see if we can re-balance by moving only one record. |
| 3262 | */ |
| 3263 | xfs_btree_get_sibling(cur, block, &rptr, XFS_BB_RIGHTSIB); |
| 3264 | xfs_btree_get_sibling(cur, block, &lptr, XFS_BB_LEFTSIB); |
| 3265 | |
| 3266 | if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) { |
| 3267 | /* |
| 3268 | * One child of root, need to get a chance to copy its contents |
| 3269 | * into the root and delete it. Can't go up to next level, |
| 3270 | * there's nothing to delete there. |
| 3271 | */ |
| 3272 | if (xfs_btree_ptr_is_null(cur, &rptr) && |
| 3273 | xfs_btree_ptr_is_null(cur, &lptr) && |
| 3274 | level == cur->bc_nlevels - 2) { |
| 3275 | error = xfs_btree_kill_iroot(cur); |
| 3276 | if (!error) |
| 3277 | error = xfs_btree_dec_cursor(cur, level, stat); |
| 3278 | if (error) |
| 3279 | goto error0; |
| 3280 | return 0; |
| 3281 | } |
| 3282 | } |
| 3283 | |
| 3284 | ASSERT(!xfs_btree_ptr_is_null(cur, &rptr) || |
| 3285 | !xfs_btree_ptr_is_null(cur, &lptr)); |
| 3286 | |
| 3287 | /* |
| 3288 | * Duplicate the cursor so our btree manipulations here won't |
| 3289 | * disrupt the next level up. |
| 3290 | */ |
| 3291 | error = xfs_btree_dup_cursor(cur, &tcur); |
| 3292 | if (error) |
| 3293 | goto error0; |
| 3294 | |
| 3295 | /* |
| 3296 | * If there's a right sibling, see if it's ok to shift an entry |
| 3297 | * out of it. |
| 3298 | */ |
| 3299 | if (!xfs_btree_ptr_is_null(cur, &rptr)) { |
| 3300 | /* |
| 3301 | * Move the temp cursor to the last entry in the next block. |
| 3302 | * Actually any entry but the first would suffice. |
| 3303 | */ |
| 3304 | i = xfs_btree_lastrec(tcur, level); |
| 3305 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); |
| 3306 | |
| 3307 | error = xfs_btree_increment(tcur, level, &i); |
| 3308 | if (error) |
| 3309 | goto error0; |
| 3310 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); |
| 3311 | |
| 3312 | i = xfs_btree_lastrec(tcur, level); |
| 3313 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); |
| 3314 | |
| 3315 | /* Grab a pointer to the block. */ |
| 3316 | right = xfs_btree_get_block(tcur, level, &rbp); |
| 3317 | #ifdef DEBUG |
| 3318 | error = xfs_btree_check_block(tcur, right, level, rbp); |
| 3319 | if (error) |
| 3320 | goto error0; |
| 3321 | #endif |
| 3322 | /* Grab the current block number, for future use. */ |
| 3323 | xfs_btree_get_sibling(tcur, right, &cptr, XFS_BB_LEFTSIB); |
| 3324 | |
| 3325 | /* |
| 3326 | * If right block is full enough so that removing one entry |
| 3327 | * won't make it too empty, and left-shifting an entry out |
| 3328 | * of right to us works, we're done. |
| 3329 | */ |
| 3330 | if (xfs_btree_get_numrecs(right) - 1 >= |
| 3331 | cur->bc_ops->get_minrecs(tcur, level)) { |
| 3332 | error = xfs_btree_lshift(tcur, level, &i); |
| 3333 | if (error) |
| 3334 | goto error0; |
| 3335 | if (i) { |
| 3336 | ASSERT(xfs_btree_get_numrecs(block) >= |
| 3337 | cur->bc_ops->get_minrecs(tcur, level)); |
| 3338 | |
| 3339 | xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR); |
| 3340 | tcur = NULL; |
| 3341 | |
| 3342 | error = xfs_btree_dec_cursor(cur, level, stat); |
| 3343 | if (error) |
| 3344 | goto error0; |
| 3345 | return 0; |
| 3346 | } |
| 3347 | } |
| 3348 | |
| 3349 | /* |
| 3350 | * Otherwise, grab the number of records in right for |
| 3351 | * future reference, and fix up the temp cursor to point |
| 3352 | * to our block again (last record). |
| 3353 | */ |
| 3354 | rrecs = xfs_btree_get_numrecs(right); |
| 3355 | if (!xfs_btree_ptr_is_null(cur, &lptr)) { |
| 3356 | i = xfs_btree_firstrec(tcur, level); |
| 3357 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); |
| 3358 | |
| 3359 | error = xfs_btree_decrement(tcur, level, &i); |
| 3360 | if (error) |
| 3361 | goto error0; |
| 3362 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); |
| 3363 | } |
| 3364 | } |
| 3365 | |
| 3366 | /* |
| 3367 | * If there's a left sibling, see if it's ok to shift an entry |
| 3368 | * out of it. |
| 3369 | */ |
| 3370 | if (!xfs_btree_ptr_is_null(cur, &lptr)) { |
| 3371 | /* |
| 3372 | * Move the temp cursor to the first entry in the |
| 3373 | * previous block. |
| 3374 | */ |
| 3375 | i = xfs_btree_firstrec(tcur, level); |
| 3376 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); |
| 3377 | |
| 3378 | error = xfs_btree_decrement(tcur, level, &i); |
| 3379 | if (error) |
| 3380 | goto error0; |
| 3381 | i = xfs_btree_firstrec(tcur, level); |
| 3382 | XFS_WANT_CORRUPTED_GOTO(i == 1, error0); |
| 3383 | |
| 3384 | /* Grab a pointer to the block. */ |
| 3385 | left = xfs_btree_get_block(tcur, level, &lbp); |
| 3386 | #ifdef DEBUG |
| 3387 | error = xfs_btree_check_block(cur, left, level, lbp); |
| 3388 | if (error) |
| 3389 | goto error0; |
| 3390 | #endif |
| 3391 | /* Grab the current block number, for future use. */ |
| 3392 | xfs_btree_get_sibling(tcur, left, &cptr, XFS_BB_RIGHTSIB); |
| 3393 | |
| 3394 | /* |
| 3395 | * If left block is full enough so that removing one entry |
| 3396 | * won't make it too empty, and right-shifting an entry out |
| 3397 | * of left to us works, we're done. |
| 3398 | */ |
| 3399 | if (xfs_btree_get_numrecs(left) - 1 >= |
| 3400 | cur->bc_ops->get_minrecs(tcur, level)) { |
| 3401 | error = xfs_btree_rshift(tcur, level, &i); |
| 3402 | if (error) |
| 3403 | goto error0; |
| 3404 | if (i) { |
| 3405 | ASSERT(xfs_btree_get_numrecs(block) >= |
| 3406 | cur->bc_ops->get_minrecs(tcur, level)); |
| 3407 | xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR); |
| 3408 | tcur = NULL; |
| 3409 | if (level == 0) |
| 3410 | cur->bc_ptrs[0]++; |
| 3411 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 3412 | *stat = 1; |
| 3413 | return 0; |
| 3414 | } |
| 3415 | } |
| 3416 | |
| 3417 | /* |
| 3418 | * Otherwise, grab the number of records in right for |
| 3419 | * future reference. |
| 3420 | */ |
| 3421 | lrecs = xfs_btree_get_numrecs(left); |
| 3422 | } |
| 3423 | |
| 3424 | /* Delete the temp cursor, we're done with it. */ |
| 3425 | xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR); |
| 3426 | tcur = NULL; |
| 3427 | |
| 3428 | /* If here, we need to do a join to keep the tree balanced. */ |
| 3429 | ASSERT(!xfs_btree_ptr_is_null(cur, &cptr)); |
| 3430 | |
| 3431 | if (!xfs_btree_ptr_is_null(cur, &lptr) && |
| 3432 | lrecs + xfs_btree_get_numrecs(block) <= |
| 3433 | cur->bc_ops->get_maxrecs(cur, level)) { |
| 3434 | /* |
| 3435 | * Set "right" to be the starting block, |
| 3436 | * "left" to be the left neighbor. |
| 3437 | */ |
| 3438 | rptr = cptr; |
| 3439 | right = block; |
| 3440 | rbp = bp; |
| 3441 | error = xfs_btree_read_buf_block(cur, &lptr, level, |
| 3442 | 0, &left, &lbp); |
| 3443 | if (error) |
| 3444 | goto error0; |
| 3445 | |
| 3446 | /* |
| 3447 | * If that won't work, see if we can join with the right neighbor block. |
| 3448 | */ |
| 3449 | } else if (!xfs_btree_ptr_is_null(cur, &rptr) && |
| 3450 | rrecs + xfs_btree_get_numrecs(block) <= |
| 3451 | cur->bc_ops->get_maxrecs(cur, level)) { |
| 3452 | /* |
| 3453 | * Set "left" to be the starting block, |
| 3454 | * "right" to be the right neighbor. |
| 3455 | */ |
| 3456 | lptr = cptr; |
| 3457 | left = block; |
| 3458 | lbp = bp; |
| 3459 | error = xfs_btree_read_buf_block(cur, &rptr, level, |
| 3460 | 0, &right, &rbp); |
| 3461 | if (error) |
| 3462 | goto error0; |
| 3463 | |
| 3464 | /* |
| 3465 | * Otherwise, we can't fix the imbalance. |
| 3466 | * Just return. This is probably a logic error, but it's not fatal. |
| 3467 | */ |
| 3468 | } else { |
| 3469 | error = xfs_btree_dec_cursor(cur, level, stat); |
| 3470 | if (error) |
| 3471 | goto error0; |
| 3472 | return 0; |
| 3473 | } |
| 3474 | |
| 3475 | rrecs = xfs_btree_get_numrecs(right); |
| 3476 | lrecs = xfs_btree_get_numrecs(left); |
| 3477 | |
| 3478 | /* |
| 3479 | * We're now going to join "left" and "right" by moving all the stuff |
| 3480 | * in "right" to "left" and deleting "right". |
| 3481 | */ |
| 3482 | XFS_BTREE_STATS_ADD(cur, moves, rrecs); |
| 3483 | if (level > 0) { |
| 3484 | /* It's a non-leaf. Move keys and pointers. */ |
| 3485 | union xfs_btree_key *lkp; /* left btree key */ |
| 3486 | union xfs_btree_ptr *lpp; /* left address pointer */ |
| 3487 | union xfs_btree_key *rkp; /* right btree key */ |
| 3488 | union xfs_btree_ptr *rpp; /* right address pointer */ |
| 3489 | |
| 3490 | lkp = xfs_btree_key_addr(cur, lrecs + 1, left); |
| 3491 | lpp = xfs_btree_ptr_addr(cur, lrecs + 1, left); |
| 3492 | rkp = xfs_btree_key_addr(cur, 1, right); |
| 3493 | rpp = xfs_btree_ptr_addr(cur, 1, right); |
| 3494 | #ifdef DEBUG |
| 3495 | for (i = 1; i < rrecs; i++) { |
| 3496 | error = xfs_btree_check_ptr(cur, rpp, i, level); |
| 3497 | if (error) |
| 3498 | goto error0; |
| 3499 | } |
| 3500 | #endif |
| 3501 | xfs_btree_copy_keys(cur, lkp, rkp, rrecs); |
| 3502 | xfs_btree_copy_ptrs(cur, lpp, rpp, rrecs); |
| 3503 | |
| 3504 | xfs_btree_log_keys(cur, lbp, lrecs + 1, lrecs + rrecs); |
| 3505 | xfs_btree_log_ptrs(cur, lbp, lrecs + 1, lrecs + rrecs); |
| 3506 | } else { |
| 3507 | /* It's a leaf. Move records. */ |
| 3508 | union xfs_btree_rec *lrp; /* left record pointer */ |
| 3509 | union xfs_btree_rec *rrp; /* right record pointer */ |
| 3510 | |
| 3511 | lrp = xfs_btree_rec_addr(cur, lrecs + 1, left); |
| 3512 | rrp = xfs_btree_rec_addr(cur, 1, right); |
| 3513 | |
| 3514 | xfs_btree_copy_recs(cur, lrp, rrp, rrecs); |
| 3515 | xfs_btree_log_recs(cur, lbp, lrecs + 1, lrecs + rrecs); |
| 3516 | } |
| 3517 | |
| 3518 | XFS_BTREE_STATS_INC(cur, join); |
| 3519 | |
| 3520 | /* |
| 3521 | * Fix up the number of records and right block pointer in the |
| 3522 | * surviving block, and log it. |
| 3523 | */ |
| 3524 | xfs_btree_set_numrecs(left, lrecs + rrecs); |
| 3525 | xfs_btree_get_sibling(cur, right, &cptr, XFS_BB_RIGHTSIB), |
| 3526 | xfs_btree_set_sibling(cur, left, &cptr, XFS_BB_RIGHTSIB); |
| 3527 | xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS | XFS_BB_RIGHTSIB); |
| 3528 | |
| 3529 | /* If there is a right sibling, point it to the remaining block. */ |
| 3530 | xfs_btree_get_sibling(cur, left, &cptr, XFS_BB_RIGHTSIB); |
| 3531 | if (!xfs_btree_ptr_is_null(cur, &cptr)) { |
| 3532 | error = xfs_btree_read_buf_block(cur, &cptr, level, |
| 3533 | 0, &rrblock, &rrbp); |
| 3534 | if (error) |
| 3535 | goto error0; |
| 3536 | xfs_btree_set_sibling(cur, rrblock, &lptr, XFS_BB_LEFTSIB); |
| 3537 | xfs_btree_log_block(cur, rrbp, XFS_BB_LEFTSIB); |
| 3538 | } |
| 3539 | |
| 3540 | /* Free the deleted block. */ |
| 3541 | error = cur->bc_ops->free_block(cur, rbp); |
| 3542 | if (error) |
| 3543 | goto error0; |
| 3544 | XFS_BTREE_STATS_INC(cur, free); |
| 3545 | |
| 3546 | /* |
| 3547 | * If we joined with the left neighbor, set the buffer in the |
| 3548 | * cursor to the left block, and fix up the index. |
| 3549 | */ |
| 3550 | if (bp != lbp) { |
| 3551 | cur->bc_bufs[level] = lbp; |
| 3552 | cur->bc_ptrs[level] += lrecs; |
| 3553 | cur->bc_ra[level] = 0; |
| 3554 | } |
| 3555 | /* |
| 3556 | * If we joined with the right neighbor and there's a level above |
| 3557 | * us, increment the cursor at that level. |
| 3558 | */ |
| 3559 | else if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) || |
| 3560 | (level + 1 < cur->bc_nlevels)) { |
| 3561 | error = xfs_btree_increment(cur, level + 1, &i); |
| 3562 | if (error) |
| 3563 | goto error0; |
| 3564 | } |
| 3565 | |
| 3566 | /* |
| 3567 | * Readjust the ptr at this level if it's not a leaf, since it's |
| 3568 | * still pointing at the deletion point, which makes the cursor |
| 3569 | * inconsistent. If this makes the ptr 0, the caller fixes it up. |
| 3570 | * We can't use decrement because it would change the next level up. |
| 3571 | */ |
| 3572 | if (level > 0) |
| 3573 | cur->bc_ptrs[level]--; |
| 3574 | |
| 3575 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 3576 | /* Return value means the next level up has something to do. */ |
| 3577 | *stat = 2; |
| 3578 | return 0; |
| 3579 | |
| 3580 | error0: |
| 3581 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| 3582 | if (tcur) |
| 3583 | xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR); |
| 3584 | return error; |
| 3585 | } |
| 3586 | |
| 3587 | /* |
| 3588 | * Delete the record pointed to by cur. |
| 3589 | * The cursor refers to the place where the record was (could be inserted) |
| 3590 | * when the operation returns. |
| 3591 | */ |
| 3592 | int /* error */ |
| 3593 | xfs_btree_delete( |
| 3594 | struct xfs_btree_cur *cur, |
| 3595 | int *stat) /* success/failure */ |
| 3596 | { |
| 3597 | int error; /* error return value */ |
| 3598 | int level; |
| 3599 | int i; |
| 3600 | |
| 3601 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY); |
| 3602 | |
| 3603 | /* |
| 3604 | * Go up the tree, starting at leaf level. |
| 3605 | * |
| 3606 | * If 2 is returned then a join was done; go to the next level. |
| 3607 | * Otherwise we are done. |
| 3608 | */ |
| 3609 | for (level = 0, i = 2; i == 2; level++) { |
| 3610 | error = xfs_btree_delrec(cur, level, &i); |
| 3611 | if (error) |
| 3612 | goto error0; |
| 3613 | } |
| 3614 | |
| 3615 | if (i == 0) { |
| 3616 | for (level = 1; level < cur->bc_nlevels; level++) { |
| 3617 | if (cur->bc_ptrs[level] == 0) { |
| 3618 | error = xfs_btree_decrement(cur, level, &i); |
| 3619 | if (error) |
| 3620 | goto error0; |
| 3621 | break; |
| 3622 | } |
| 3623 | } |
| 3624 | } |
| 3625 | |
| 3626 | XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT); |
| 3627 | *stat = i; |
| 3628 | return 0; |
| 3629 | error0: |
| 3630 | XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR); |
| 3631 | return error; |
| 3632 | } |
| 3633 | |
| 3634 | /* |
| 3635 | * Get the data from the pointed-to record. |
| 3636 | */ |
| 3637 | int /* error */ |
| 3638 | xfs_btree_get_rec( |
| 3639 | struct xfs_btree_cur *cur, /* btree cursor */ |
| 3640 | union xfs_btree_rec **recp, /* output: btree record */ |
| 3641 | int *stat) /* output: success/failure */ |
| 3642 | { |
| 3643 | struct xfs_btree_block *block; /* btree block */ |
| 3644 | struct xfs_buf *bp; /* buffer pointer */ |
| 3645 | int ptr; /* record number */ |
| 3646 | #ifdef DEBUG |
| 3647 | int error; /* error return value */ |
| 3648 | #endif |
| 3649 | |
| 3650 | ptr = cur->bc_ptrs[0]; |
| 3651 | block = xfs_btree_get_block(cur, 0, &bp); |
| 3652 | |
| 3653 | #ifdef DEBUG |
| 3654 | error = xfs_btree_check_block(cur, block, 0, bp); |
| 3655 | if (error) |
| 3656 | return error; |
| 3657 | #endif |
| 3658 | |
| 3659 | /* |
| 3660 | * Off the right end or left end, return failure. |
| 3661 | */ |
| 3662 | if (ptr > xfs_btree_get_numrecs(block) || ptr <= 0) { |
| 3663 | *stat = 0; |
| 3664 | return 0; |
| 3665 | } |
| 3666 | |
| 3667 | /* |
| 3668 | * Point to the record and extract its data. |
| 3669 | */ |
| 3670 | *recp = xfs_btree_rec_addr(cur, ptr, block); |
| 3671 | *stat = 1; |
| 3672 | return 0; |
| 3673 | } |