2 * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
20 #include "xfs_shared.h"
21 #include "xfs_format.h"
22 #include "xfs_log_format.h"
23 #include "xfs_trans_resv.h"
25 #include "xfs_mount.h"
26 #include "xfs_defer.h"
27 #include "xfs_inode.h"
28 #include "xfs_trans.h"
29 #include "xfs_inode_item.h"
30 #include "xfs_buf_item.h"
31 #include "xfs_btree.h"
32 #include "xfs_error.h"
33 #include "xfs_trace.h"
34 #include "xfs_cksum.h"
35 #include "xfs_alloc.h"
39 * Cursor allocation zone.
41 kmem_zone_t *xfs_btree_cur_zone;
44 * Btree magic numbers.
46 static const __uint32_t xfs_magics[2][XFS_BTNUM_MAX] = {
47 { XFS_ABTB_MAGIC, XFS_ABTC_MAGIC, 0, XFS_BMAP_MAGIC, XFS_IBT_MAGIC,
49 { XFS_ABTB_CRC_MAGIC, XFS_ABTC_CRC_MAGIC, XFS_RMAP_CRC_MAGIC,
50 XFS_BMAP_CRC_MAGIC, XFS_IBT_CRC_MAGIC, XFS_FIBT_CRC_MAGIC,
59 __uint32_t magic = xfs_magics[crc][btnum];
61 /* Ensure we asked for crc for crc-only magics. */
66 STATIC int /* error (0 or EFSCORRUPTED) */
67 xfs_btree_check_lblock(
68 struct xfs_btree_cur *cur, /* btree cursor */
69 struct xfs_btree_block *block, /* btree long form block pointer */
70 int level, /* level of the btree block */
71 struct xfs_buf *bp) /* buffer for block, if any */
73 int lblock_ok = 1; /* block passes checks */
74 struct xfs_mount *mp; /* file system mount point */
75 xfs_btnum_t btnum = cur->bc_btnum;
79 crc = xfs_sb_version_hascrc(&mp->m_sb);
82 lblock_ok = lblock_ok &&
83 uuid_equal(&block->bb_u.l.bb_uuid,
84 &mp->m_sb.sb_meta_uuid) &&
85 block->bb_u.l.bb_blkno == cpu_to_be64(
86 bp ? bp->b_bn : XFS_BUF_DADDR_NULL);
89 lblock_ok = lblock_ok &&
90 be32_to_cpu(block->bb_magic) == xfs_btree_magic(crc, btnum) &&
91 be16_to_cpu(block->bb_level) == level &&
92 be16_to_cpu(block->bb_numrecs) <=
93 cur->bc_ops->get_maxrecs(cur, level) &&
94 block->bb_u.l.bb_leftsib &&
95 (block->bb_u.l.bb_leftsib == cpu_to_be64(NULLFSBLOCK) ||
96 XFS_FSB_SANITY_CHECK(mp,
97 be64_to_cpu(block->bb_u.l.bb_leftsib))) &&
98 block->bb_u.l.bb_rightsib &&
99 (block->bb_u.l.bb_rightsib == cpu_to_be64(NULLFSBLOCK) ||
100 XFS_FSB_SANITY_CHECK(mp,
101 be64_to_cpu(block->bb_u.l.bb_rightsib)));
103 if (unlikely(XFS_TEST_ERROR(!lblock_ok, mp,
104 XFS_ERRTAG_BTREE_CHECK_LBLOCK,
105 XFS_RANDOM_BTREE_CHECK_LBLOCK))) {
107 trace_xfs_btree_corrupt(bp, _RET_IP_);
108 XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, mp);
109 return -EFSCORRUPTED;
114 STATIC int /* error (0 or EFSCORRUPTED) */
115 xfs_btree_check_sblock(
116 struct xfs_btree_cur *cur, /* btree cursor */
117 struct xfs_btree_block *block, /* btree short form block pointer */
118 int level, /* level of the btree block */
119 struct xfs_buf *bp) /* buffer containing block */
121 struct xfs_mount *mp; /* file system mount point */
122 struct xfs_buf *agbp; /* buffer for ag. freespace struct */
123 struct xfs_agf *agf; /* ag. freespace structure */
124 xfs_agblock_t agflen; /* native ag. freespace length */
125 int sblock_ok = 1; /* block passes checks */
126 xfs_btnum_t btnum = cur->bc_btnum;
130 crc = xfs_sb_version_hascrc(&mp->m_sb);
131 agbp = cur->bc_private.a.agbp;
132 agf = XFS_BUF_TO_AGF(agbp);
133 agflen = be32_to_cpu(agf->agf_length);
136 sblock_ok = sblock_ok &&
137 uuid_equal(&block->bb_u.s.bb_uuid,
138 &mp->m_sb.sb_meta_uuid) &&
139 block->bb_u.s.bb_blkno == cpu_to_be64(
140 bp ? bp->b_bn : XFS_BUF_DADDR_NULL);
143 sblock_ok = sblock_ok &&
144 be32_to_cpu(block->bb_magic) == xfs_btree_magic(crc, btnum) &&
145 be16_to_cpu(block->bb_level) == level &&
146 be16_to_cpu(block->bb_numrecs) <=
147 cur->bc_ops->get_maxrecs(cur, level) &&
148 (block->bb_u.s.bb_leftsib == cpu_to_be32(NULLAGBLOCK) ||
149 be32_to_cpu(block->bb_u.s.bb_leftsib) < agflen) &&
150 block->bb_u.s.bb_leftsib &&
151 (block->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK) ||
152 be32_to_cpu(block->bb_u.s.bb_rightsib) < agflen) &&
153 block->bb_u.s.bb_rightsib;
155 if (unlikely(XFS_TEST_ERROR(!sblock_ok, mp,
156 XFS_ERRTAG_BTREE_CHECK_SBLOCK,
157 XFS_RANDOM_BTREE_CHECK_SBLOCK))) {
159 trace_xfs_btree_corrupt(bp, _RET_IP_);
160 XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, mp);
161 return -EFSCORRUPTED;
167 * Debug routine: check that block header is ok.
170 xfs_btree_check_block(
171 struct xfs_btree_cur *cur, /* btree cursor */
172 struct xfs_btree_block *block, /* generic btree block pointer */
173 int level, /* level of the btree block */
174 struct xfs_buf *bp) /* buffer containing block, if any */
176 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
177 return xfs_btree_check_lblock(cur, block, level, bp);
179 return xfs_btree_check_sblock(cur, block, level, bp);
183 * Check that (long) pointer is ok.
185 int /* error (0 or EFSCORRUPTED) */
186 xfs_btree_check_lptr(
187 struct xfs_btree_cur *cur, /* btree cursor */
188 xfs_fsblock_t bno, /* btree block disk address */
189 int level) /* btree block level */
191 XFS_WANT_CORRUPTED_RETURN(cur->bc_mp,
193 bno != NULLFSBLOCK &&
194 XFS_FSB_SANITY_CHECK(cur->bc_mp, bno));
200 * Check that (short) pointer is ok.
202 STATIC int /* error (0 or EFSCORRUPTED) */
203 xfs_btree_check_sptr(
204 struct xfs_btree_cur *cur, /* btree cursor */
205 xfs_agblock_t bno, /* btree block disk address */
206 int level) /* btree block level */
208 xfs_agblock_t agblocks = cur->bc_mp->m_sb.sb_agblocks;
210 XFS_WANT_CORRUPTED_RETURN(cur->bc_mp,
212 bno != NULLAGBLOCK &&
219 * Check that block ptr is ok.
221 STATIC int /* error (0 or EFSCORRUPTED) */
223 struct xfs_btree_cur *cur, /* btree cursor */
224 union xfs_btree_ptr *ptr, /* btree block disk address */
225 int index, /* offset from ptr to check */
226 int level) /* btree block level */
228 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
229 return xfs_btree_check_lptr(cur,
230 be64_to_cpu((&ptr->l)[index]), level);
232 return xfs_btree_check_sptr(cur,
233 be32_to_cpu((&ptr->s)[index]), level);
239 * Calculate CRC on the whole btree block and stuff it into the
240 * long-form btree header.
242 * Prior to calculting the CRC, pull the LSN out of the buffer log item and put
243 * it into the buffer so recovery knows what the last modification was that made
247 xfs_btree_lblock_calc_crc(
250 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
251 struct xfs_buf_log_item *bip = bp->b_fspriv;
253 if (!xfs_sb_version_hascrc(&bp->b_target->bt_mount->m_sb))
256 block->bb_u.l.bb_lsn = cpu_to_be64(bip->bli_item.li_lsn);
257 xfs_buf_update_cksum(bp, XFS_BTREE_LBLOCK_CRC_OFF);
261 xfs_btree_lblock_verify_crc(
264 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
265 struct xfs_mount *mp = bp->b_target->bt_mount;
267 if (xfs_sb_version_hascrc(&mp->m_sb)) {
268 if (!xfs_log_check_lsn(mp, be64_to_cpu(block->bb_u.l.bb_lsn)))
270 return xfs_buf_verify_cksum(bp, XFS_BTREE_LBLOCK_CRC_OFF);
277 * Calculate CRC on the whole btree block and stuff it into the
278 * short-form btree header.
280 * Prior to calculting the CRC, pull the LSN out of the buffer log item and put
281 * it into the buffer so recovery knows what the last modification was that made
285 xfs_btree_sblock_calc_crc(
288 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
289 struct xfs_buf_log_item *bip = bp->b_fspriv;
291 if (!xfs_sb_version_hascrc(&bp->b_target->bt_mount->m_sb))
294 block->bb_u.s.bb_lsn = cpu_to_be64(bip->bli_item.li_lsn);
295 xfs_buf_update_cksum(bp, XFS_BTREE_SBLOCK_CRC_OFF);
299 xfs_btree_sblock_verify_crc(
302 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
303 struct xfs_mount *mp = bp->b_target->bt_mount;
305 if (xfs_sb_version_hascrc(&mp->m_sb)) {
306 if (!xfs_log_check_lsn(mp, be64_to_cpu(block->bb_u.s.bb_lsn)))
308 return xfs_buf_verify_cksum(bp, XFS_BTREE_SBLOCK_CRC_OFF);
315 xfs_btree_free_block(
316 struct xfs_btree_cur *cur,
321 error = cur->bc_ops->free_block(cur, bp);
323 xfs_trans_binval(cur->bc_tp, bp);
324 XFS_BTREE_STATS_INC(cur, free);
330 * Delete the btree cursor.
333 xfs_btree_del_cursor(
334 xfs_btree_cur_t *cur, /* btree cursor */
335 int error) /* del because of error */
337 int i; /* btree level */
340 * Clear the buffer pointers, and release the buffers.
341 * If we're doing this in the face of an error, we
342 * need to make sure to inspect all of the entries
343 * in the bc_bufs array for buffers to be unlocked.
344 * This is because some of the btree code works from
345 * level n down to 0, and if we get an error along
346 * the way we won't have initialized all the entries
349 for (i = 0; i < cur->bc_nlevels; i++) {
351 xfs_trans_brelse(cur->bc_tp, cur->bc_bufs[i]);
356 * Can't free a bmap cursor without having dealt with the
357 * allocated indirect blocks' accounting.
359 ASSERT(cur->bc_btnum != XFS_BTNUM_BMAP ||
360 cur->bc_private.b.allocated == 0);
364 kmem_zone_free(xfs_btree_cur_zone, cur);
368 * Duplicate the btree cursor.
369 * Allocate a new one, copy the record, re-get the buffers.
372 xfs_btree_dup_cursor(
373 xfs_btree_cur_t *cur, /* input cursor */
374 xfs_btree_cur_t **ncur) /* output cursor */
376 xfs_buf_t *bp; /* btree block's buffer pointer */
377 int error; /* error return value */
378 int i; /* level number of btree block */
379 xfs_mount_t *mp; /* mount structure for filesystem */
380 xfs_btree_cur_t *new; /* new cursor value */
381 xfs_trans_t *tp; /* transaction pointer, can be NULL */
387 * Allocate a new cursor like the old one.
389 new = cur->bc_ops->dup_cursor(cur);
392 * Copy the record currently in the cursor.
394 new->bc_rec = cur->bc_rec;
397 * For each level current, re-get the buffer and copy the ptr value.
399 for (i = 0; i < new->bc_nlevels; i++) {
400 new->bc_ptrs[i] = cur->bc_ptrs[i];
401 new->bc_ra[i] = cur->bc_ra[i];
402 bp = cur->bc_bufs[i];
404 error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
405 XFS_BUF_ADDR(bp), mp->m_bsize,
407 cur->bc_ops->buf_ops);
409 xfs_btree_del_cursor(new, error);
414 new->bc_bufs[i] = bp;
421 * XFS btree block layout and addressing:
423 * There are two types of blocks in the btree: leaf and non-leaf blocks.
425 * The leaf record start with a header then followed by records containing
426 * the values. A non-leaf block also starts with the same header, and
427 * then first contains lookup keys followed by an equal number of pointers
428 * to the btree blocks at the previous level.
430 * +--------+-------+-------+-------+-------+-------+-------+
431 * Leaf: | header | rec 1 | rec 2 | rec 3 | rec 4 | rec 5 | rec N |
432 * +--------+-------+-------+-------+-------+-------+-------+
434 * +--------+-------+-------+-------+-------+-------+-------+
435 * Non-Leaf: | header | key 1 | key 2 | key N | ptr 1 | ptr 2 | ptr N |
436 * +--------+-------+-------+-------+-------+-------+-------+
438 * The header is called struct xfs_btree_block for reasons better left unknown
439 * and comes in different versions for short (32bit) and long (64bit) block
440 * pointers. The record and key structures are defined by the btree instances
441 * and opaque to the btree core. The block pointers are simple disk endian
442 * integers, available in a short (32bit) and long (64bit) variant.
444 * The helpers below calculate the offset of a given record, key or pointer
445 * into a btree block (xfs_btree_*_offset) or return a pointer to the given
446 * record, key or pointer (xfs_btree_*_addr). Note that all addressing
447 * inside the btree block is done using indices starting at one, not zero!
449 * If XFS_BTREE_OVERLAPPING is set, then this btree supports keys containing
450 * overlapping intervals. In such a tree, records are still sorted lowest to
451 * highest and indexed by the smallest key value that refers to the record.
452 * However, nodes are different: each pointer has two associated keys -- one
453 * indexing the lowest key available in the block(s) below (the same behavior
454 * as the key in a regular btree) and another indexing the highest key
455 * available in the block(s) below. Because records are /not/ sorted by the
456 * highest key, all leaf block updates require us to compute the highest key
457 * that matches any record in the leaf and to recursively update the high keys
458 * in the nodes going further up in the tree, if necessary. Nodes look like
461 * +--------+-----+-----+-----+-----+-----+-------+-------+-----+
462 * Non-Leaf: | header | lo1 | hi1 | lo2 | hi2 | ... | ptr 1 | ptr 2 | ... |
463 * +--------+-----+-----+-----+-----+-----+-------+-------+-----+
465 * To perform an interval query on an overlapped tree, perform the usual
466 * depth-first search and use the low and high keys to decide if we can skip
467 * that particular node. If a leaf node is reached, return the records that
468 * intersect the interval. Note that an interval query may return numerous
469 * entries. For a non-overlapped tree, simply search for the record associated
470 * with the lowest key and iterate forward until a non-matching record is
471 * found. Section 14.3 ("Interval Trees") of _Introduction to Algorithms_ by
472 * Cormen, Leiserson, Rivest, and Stein (2nd or 3rd ed. only) discuss this in
475 * Why do we care about overlapping intervals? Let's say you have a bunch of
476 * reverse mapping records on a reflink filesystem:
478 * 1: +- file A startblock B offset C length D -----------+
479 * 2: +- file E startblock F offset G length H --------------+
480 * 3: +- file I startblock F offset J length K --+
481 * 4: +- file L... --+
483 * Now say we want to map block (B+D) into file A at offset (C+D). Ideally,
484 * we'd simply increment the length of record 1. But how do we find the record
485 * that ends at (B+D-1) (i.e. record 1)? A LE lookup of (B+D-1) would return
486 * record 3 because the keys are ordered first by startblock. An interval
487 * query would return records 1 and 2 because they both overlap (B+D-1), and
488 * from that we can pick out record 1 as the appropriate left neighbor.
490 * In the non-overlapped case you can do a LE lookup and decrement the cursor
491 * because a record's interval must end before the next record.
495 * Return size of the btree block header for this btree instance.
497 static inline size_t xfs_btree_block_len(struct xfs_btree_cur *cur)
499 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
500 if (cur->bc_flags & XFS_BTREE_CRC_BLOCKS)
501 return XFS_BTREE_LBLOCK_CRC_LEN;
502 return XFS_BTREE_LBLOCK_LEN;
504 if (cur->bc_flags & XFS_BTREE_CRC_BLOCKS)
505 return XFS_BTREE_SBLOCK_CRC_LEN;
506 return XFS_BTREE_SBLOCK_LEN;
510 * Return size of btree block pointers for this btree instance.
512 static inline size_t xfs_btree_ptr_len(struct xfs_btree_cur *cur)
514 return (cur->bc_flags & XFS_BTREE_LONG_PTRS) ?
515 sizeof(__be64) : sizeof(__be32);
519 * Calculate offset of the n-th record in a btree block.
522 xfs_btree_rec_offset(
523 struct xfs_btree_cur *cur,
526 return xfs_btree_block_len(cur) +
527 (n - 1) * cur->bc_ops->rec_len;
531 * Calculate offset of the n-th key in a btree block.
534 xfs_btree_key_offset(
535 struct xfs_btree_cur *cur,
538 return xfs_btree_block_len(cur) +
539 (n - 1) * cur->bc_ops->key_len;
543 * Calculate offset of the n-th high key in a btree block.
546 xfs_btree_high_key_offset(
547 struct xfs_btree_cur *cur,
550 return xfs_btree_block_len(cur) +
551 (n - 1) * cur->bc_ops->key_len + (cur->bc_ops->key_len / 2);
555 * Calculate offset of the n-th block pointer in a btree block.
558 xfs_btree_ptr_offset(
559 struct xfs_btree_cur *cur,
563 return xfs_btree_block_len(cur) +
564 cur->bc_ops->get_maxrecs(cur, level) * cur->bc_ops->key_len +
565 (n - 1) * xfs_btree_ptr_len(cur);
569 * Return a pointer to the n-th record in the btree block.
571 STATIC union xfs_btree_rec *
573 struct xfs_btree_cur *cur,
575 struct xfs_btree_block *block)
577 return (union xfs_btree_rec *)
578 ((char *)block + xfs_btree_rec_offset(cur, n));
582 * Return a pointer to the n-th key in the btree block.
584 STATIC union xfs_btree_key *
586 struct xfs_btree_cur *cur,
588 struct xfs_btree_block *block)
590 return (union xfs_btree_key *)
591 ((char *)block + xfs_btree_key_offset(cur, n));
595 * Return a pointer to the n-th high key in the btree block.
597 STATIC union xfs_btree_key *
598 xfs_btree_high_key_addr(
599 struct xfs_btree_cur *cur,
601 struct xfs_btree_block *block)
603 return (union xfs_btree_key *)
604 ((char *)block + xfs_btree_high_key_offset(cur, n));
608 * Return a pointer to the n-th block pointer in the btree block.
610 STATIC union xfs_btree_ptr *
612 struct xfs_btree_cur *cur,
614 struct xfs_btree_block *block)
616 int level = xfs_btree_get_level(block);
618 ASSERT(block->bb_level != 0);
620 return (union xfs_btree_ptr *)
621 ((char *)block + xfs_btree_ptr_offset(cur, n, level));
625 * Get the root block which is stored in the inode.
627 * For now this btree implementation assumes the btree root is always
628 * stored in the if_broot field of an inode fork.
630 STATIC struct xfs_btree_block *
632 struct xfs_btree_cur *cur)
634 struct xfs_ifork *ifp;
636 ifp = XFS_IFORK_PTR(cur->bc_private.b.ip, cur->bc_private.b.whichfork);
637 return (struct xfs_btree_block *)ifp->if_broot;
641 * Retrieve the block pointer from the cursor at the given level.
642 * This may be an inode btree root or from a buffer.
644 STATIC struct xfs_btree_block * /* generic btree block pointer */
646 struct xfs_btree_cur *cur, /* btree cursor */
647 int level, /* level in btree */
648 struct xfs_buf **bpp) /* buffer containing the block */
650 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
651 (level == cur->bc_nlevels - 1)) {
653 return xfs_btree_get_iroot(cur);
656 *bpp = cur->bc_bufs[level];
657 return XFS_BUF_TO_BLOCK(*bpp);
661 * Get a buffer for the block, return it with no data read.
662 * Long-form addressing.
664 xfs_buf_t * /* buffer for fsbno */
666 xfs_mount_t *mp, /* file system mount point */
667 xfs_trans_t *tp, /* transaction pointer */
668 xfs_fsblock_t fsbno, /* file system block number */
669 uint lock) /* lock flags for get_buf */
671 xfs_daddr_t d; /* real disk block address */
673 ASSERT(fsbno != NULLFSBLOCK);
674 d = XFS_FSB_TO_DADDR(mp, fsbno);
675 return xfs_trans_get_buf(tp, mp->m_ddev_targp, d, mp->m_bsize, lock);
679 * Get a buffer for the block, return it with no data read.
680 * Short-form addressing.
682 xfs_buf_t * /* buffer for agno/agbno */
684 xfs_mount_t *mp, /* file system mount point */
685 xfs_trans_t *tp, /* transaction pointer */
686 xfs_agnumber_t agno, /* allocation group number */
687 xfs_agblock_t agbno, /* allocation group block number */
688 uint lock) /* lock flags for get_buf */
690 xfs_daddr_t d; /* real disk block address */
692 ASSERT(agno != NULLAGNUMBER);
693 ASSERT(agbno != NULLAGBLOCK);
694 d = XFS_AGB_TO_DADDR(mp, agno, agbno);
695 return xfs_trans_get_buf(tp, mp->m_ddev_targp, d, mp->m_bsize, lock);
699 * Check for the cursor referring to the last block at the given level.
701 int /* 1=is last block, 0=not last block */
702 xfs_btree_islastblock(
703 xfs_btree_cur_t *cur, /* btree cursor */
704 int level) /* level to check */
706 struct xfs_btree_block *block; /* generic btree block pointer */
707 xfs_buf_t *bp; /* buffer containing block */
709 block = xfs_btree_get_block(cur, level, &bp);
710 xfs_btree_check_block(cur, block, level, bp);
711 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
712 return block->bb_u.l.bb_rightsib == cpu_to_be64(NULLFSBLOCK);
714 return block->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK);
718 * Change the cursor to point to the first record at the given level.
719 * Other levels are unaffected.
721 STATIC int /* success=1, failure=0 */
723 xfs_btree_cur_t *cur, /* btree cursor */
724 int level) /* level to change */
726 struct xfs_btree_block *block; /* generic btree block pointer */
727 xfs_buf_t *bp; /* buffer containing block */
730 * Get the block pointer for this level.
732 block = xfs_btree_get_block(cur, level, &bp);
733 xfs_btree_check_block(cur, block, level, bp);
735 * It's empty, there is no such record.
737 if (!block->bb_numrecs)
740 * Set the ptr value to 1, that's the first record/key.
742 cur->bc_ptrs[level] = 1;
747 * Change the cursor to point to the last record in the current block
748 * at the given level. Other levels are unaffected.
750 STATIC int /* success=1, failure=0 */
752 xfs_btree_cur_t *cur, /* btree cursor */
753 int level) /* level to change */
755 struct xfs_btree_block *block; /* generic btree block pointer */
756 xfs_buf_t *bp; /* buffer containing block */
759 * Get the block pointer for this level.
761 block = xfs_btree_get_block(cur, level, &bp);
762 xfs_btree_check_block(cur, block, level, bp);
764 * It's empty, there is no such record.
766 if (!block->bb_numrecs)
769 * Set the ptr value to numrecs, that's the last record/key.
771 cur->bc_ptrs[level] = be16_to_cpu(block->bb_numrecs);
776 * Compute first and last byte offsets for the fields given.
777 * Interprets the offsets table, which contains struct field offsets.
781 __int64_t fields, /* bitmask of fields */
782 const short *offsets, /* table of field offsets */
783 int nbits, /* number of bits to inspect */
784 int *first, /* output: first byte offset */
785 int *last) /* output: last byte offset */
787 int i; /* current bit number */
788 __int64_t imask; /* mask for current bit number */
792 * Find the lowest bit, so the first byte offset.
794 for (i = 0, imask = 1LL; ; i++, imask <<= 1) {
795 if (imask & fields) {
801 * Find the highest bit, so the last byte offset.
803 for (i = nbits - 1, imask = 1LL << i; ; i--, imask >>= 1) {
804 if (imask & fields) {
805 *last = offsets[i + 1] - 1;
812 * Get a buffer for the block, return it read in.
813 * Long-form addressing.
817 struct xfs_mount *mp, /* file system mount point */
818 struct xfs_trans *tp, /* transaction pointer */
819 xfs_fsblock_t fsbno, /* file system block number */
820 uint lock, /* lock flags for read_buf */
821 struct xfs_buf **bpp, /* buffer for fsbno */
822 int refval, /* ref count value for buffer */
823 const struct xfs_buf_ops *ops)
825 struct xfs_buf *bp; /* return value */
826 xfs_daddr_t d; /* real disk block address */
829 ASSERT(fsbno != NULLFSBLOCK);
830 d = XFS_FSB_TO_DADDR(mp, fsbno);
831 error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, d,
832 mp->m_bsize, lock, &bp, ops);
836 xfs_buf_set_ref(bp, refval);
842 * Read-ahead the block, don't wait for it, don't return a buffer.
843 * Long-form addressing.
847 xfs_btree_reada_bufl(
848 struct xfs_mount *mp, /* file system mount point */
849 xfs_fsblock_t fsbno, /* file system block number */
850 xfs_extlen_t count, /* count of filesystem blocks */
851 const struct xfs_buf_ops *ops)
855 ASSERT(fsbno != NULLFSBLOCK);
856 d = XFS_FSB_TO_DADDR(mp, fsbno);
857 xfs_buf_readahead(mp->m_ddev_targp, d, mp->m_bsize * count, ops);
861 * Read-ahead the block, don't wait for it, don't return a buffer.
862 * Short-form addressing.
866 xfs_btree_reada_bufs(
867 struct xfs_mount *mp, /* file system mount point */
868 xfs_agnumber_t agno, /* allocation group number */
869 xfs_agblock_t agbno, /* allocation group block number */
870 xfs_extlen_t count, /* count of filesystem blocks */
871 const struct xfs_buf_ops *ops)
875 ASSERT(agno != NULLAGNUMBER);
876 ASSERT(agbno != NULLAGBLOCK);
877 d = XFS_AGB_TO_DADDR(mp, agno, agbno);
878 xfs_buf_readahead(mp->m_ddev_targp, d, mp->m_bsize * count, ops);
882 xfs_btree_readahead_lblock(
883 struct xfs_btree_cur *cur,
885 struct xfs_btree_block *block)
888 xfs_fsblock_t left = be64_to_cpu(block->bb_u.l.bb_leftsib);
889 xfs_fsblock_t right = be64_to_cpu(block->bb_u.l.bb_rightsib);
891 if ((lr & XFS_BTCUR_LEFTRA) && left != NULLFSBLOCK) {
892 xfs_btree_reada_bufl(cur->bc_mp, left, 1,
893 cur->bc_ops->buf_ops);
897 if ((lr & XFS_BTCUR_RIGHTRA) && right != NULLFSBLOCK) {
898 xfs_btree_reada_bufl(cur->bc_mp, right, 1,
899 cur->bc_ops->buf_ops);
907 xfs_btree_readahead_sblock(
908 struct xfs_btree_cur *cur,
910 struct xfs_btree_block *block)
913 xfs_agblock_t left = be32_to_cpu(block->bb_u.s.bb_leftsib);
914 xfs_agblock_t right = be32_to_cpu(block->bb_u.s.bb_rightsib);
917 if ((lr & XFS_BTCUR_LEFTRA) && left != NULLAGBLOCK) {
918 xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.a.agno,
919 left, 1, cur->bc_ops->buf_ops);
923 if ((lr & XFS_BTCUR_RIGHTRA) && right != NULLAGBLOCK) {
924 xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.a.agno,
925 right, 1, cur->bc_ops->buf_ops);
933 * Read-ahead btree blocks, at the given level.
934 * Bits in lr are set from XFS_BTCUR_{LEFT,RIGHT}RA.
938 struct xfs_btree_cur *cur, /* btree cursor */
939 int lev, /* level in btree */
940 int lr) /* left/right bits */
942 struct xfs_btree_block *block;
945 * No readahead needed if we are at the root level and the
946 * btree root is stored in the inode.
948 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
949 (lev == cur->bc_nlevels - 1))
952 if ((cur->bc_ra[lev] | lr) == cur->bc_ra[lev])
955 cur->bc_ra[lev] |= lr;
956 block = XFS_BUF_TO_BLOCK(cur->bc_bufs[lev]);
958 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
959 return xfs_btree_readahead_lblock(cur, lr, block);
960 return xfs_btree_readahead_sblock(cur, lr, block);
964 xfs_btree_ptr_to_daddr(
965 struct xfs_btree_cur *cur,
966 union xfs_btree_ptr *ptr)
968 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
969 ASSERT(ptr->l != cpu_to_be64(NULLFSBLOCK));
971 return XFS_FSB_TO_DADDR(cur->bc_mp, be64_to_cpu(ptr->l));
973 ASSERT(cur->bc_private.a.agno != NULLAGNUMBER);
974 ASSERT(ptr->s != cpu_to_be32(NULLAGBLOCK));
976 return XFS_AGB_TO_DADDR(cur->bc_mp, cur->bc_private.a.agno,
977 be32_to_cpu(ptr->s));
982 * Readahead @count btree blocks at the given @ptr location.
984 * We don't need to care about long or short form btrees here as we have a
985 * method of converting the ptr directly to a daddr available to us.
988 xfs_btree_readahead_ptr(
989 struct xfs_btree_cur *cur,
990 union xfs_btree_ptr *ptr,
993 xfs_buf_readahead(cur->bc_mp->m_ddev_targp,
994 xfs_btree_ptr_to_daddr(cur, ptr),
995 cur->bc_mp->m_bsize * count, cur->bc_ops->buf_ops);
999 * Set the buffer for level "lev" in the cursor to bp, releasing
1000 * any previous buffer.
1004 xfs_btree_cur_t *cur, /* btree cursor */
1005 int lev, /* level in btree */
1006 xfs_buf_t *bp) /* new buffer to set */
1008 struct xfs_btree_block *b; /* btree block */
1010 if (cur->bc_bufs[lev])
1011 xfs_trans_brelse(cur->bc_tp, cur->bc_bufs[lev]);
1012 cur->bc_bufs[lev] = bp;
1013 cur->bc_ra[lev] = 0;
1015 b = XFS_BUF_TO_BLOCK(bp);
1016 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
1017 if (b->bb_u.l.bb_leftsib == cpu_to_be64(NULLFSBLOCK))
1018 cur->bc_ra[lev] |= XFS_BTCUR_LEFTRA;
1019 if (b->bb_u.l.bb_rightsib == cpu_to_be64(NULLFSBLOCK))
1020 cur->bc_ra[lev] |= XFS_BTCUR_RIGHTRA;
1022 if (b->bb_u.s.bb_leftsib == cpu_to_be32(NULLAGBLOCK))
1023 cur->bc_ra[lev] |= XFS_BTCUR_LEFTRA;
1024 if (b->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK))
1025 cur->bc_ra[lev] |= XFS_BTCUR_RIGHTRA;
1030 xfs_btree_ptr_is_null(
1031 struct xfs_btree_cur *cur,
1032 union xfs_btree_ptr *ptr)
1034 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
1035 return ptr->l == cpu_to_be64(NULLFSBLOCK);
1037 return ptr->s == cpu_to_be32(NULLAGBLOCK);
1041 xfs_btree_set_ptr_null(
1042 struct xfs_btree_cur *cur,
1043 union xfs_btree_ptr *ptr)
1045 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
1046 ptr->l = cpu_to_be64(NULLFSBLOCK);
1048 ptr->s = cpu_to_be32(NULLAGBLOCK);
1052 * Get/set/init sibling pointers
1055 xfs_btree_get_sibling(
1056 struct xfs_btree_cur *cur,
1057 struct xfs_btree_block *block,
1058 union xfs_btree_ptr *ptr,
1061 ASSERT(lr == XFS_BB_LEFTSIB || lr == XFS_BB_RIGHTSIB);
1063 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
1064 if (lr == XFS_BB_RIGHTSIB)
1065 ptr->l = block->bb_u.l.bb_rightsib;
1067 ptr->l = block->bb_u.l.bb_leftsib;
1069 if (lr == XFS_BB_RIGHTSIB)
1070 ptr->s = block->bb_u.s.bb_rightsib;
1072 ptr->s = block->bb_u.s.bb_leftsib;
1077 xfs_btree_set_sibling(
1078 struct xfs_btree_cur *cur,
1079 struct xfs_btree_block *block,
1080 union xfs_btree_ptr *ptr,
1083 ASSERT(lr == XFS_BB_LEFTSIB || lr == XFS_BB_RIGHTSIB);
1085 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
1086 if (lr == XFS_BB_RIGHTSIB)
1087 block->bb_u.l.bb_rightsib = ptr->l;
1089 block->bb_u.l.bb_leftsib = ptr->l;
1091 if (lr == XFS_BB_RIGHTSIB)
1092 block->bb_u.s.bb_rightsib = ptr->s;
1094 block->bb_u.s.bb_leftsib = ptr->s;
1099 xfs_btree_init_block_int(
1100 struct xfs_mount *mp,
1101 struct xfs_btree_block *buf,
1109 int crc = xfs_sb_version_hascrc(&mp->m_sb);
1110 __u32 magic = xfs_btree_magic(crc, btnum);
1112 buf->bb_magic = cpu_to_be32(magic);
1113 buf->bb_level = cpu_to_be16(level);
1114 buf->bb_numrecs = cpu_to_be16(numrecs);
1116 if (flags & XFS_BTREE_LONG_PTRS) {
1117 buf->bb_u.l.bb_leftsib = cpu_to_be64(NULLFSBLOCK);
1118 buf->bb_u.l.bb_rightsib = cpu_to_be64(NULLFSBLOCK);
1120 buf->bb_u.l.bb_blkno = cpu_to_be64(blkno);
1121 buf->bb_u.l.bb_owner = cpu_to_be64(owner);
1122 uuid_copy(&buf->bb_u.l.bb_uuid, &mp->m_sb.sb_meta_uuid);
1123 buf->bb_u.l.bb_pad = 0;
1124 buf->bb_u.l.bb_lsn = 0;
1127 /* owner is a 32 bit value on short blocks */
1128 __u32 __owner = (__u32)owner;
1130 buf->bb_u.s.bb_leftsib = cpu_to_be32(NULLAGBLOCK);
1131 buf->bb_u.s.bb_rightsib = cpu_to_be32(NULLAGBLOCK);
1133 buf->bb_u.s.bb_blkno = cpu_to_be64(blkno);
1134 buf->bb_u.s.bb_owner = cpu_to_be32(__owner);
1135 uuid_copy(&buf->bb_u.s.bb_uuid, &mp->m_sb.sb_meta_uuid);
1136 buf->bb_u.s.bb_lsn = 0;
1142 xfs_btree_init_block(
1143 struct xfs_mount *mp,
1151 xfs_btree_init_block_int(mp, XFS_BUF_TO_BLOCK(bp), bp->b_bn,
1152 btnum, level, numrecs, owner, flags);
1156 xfs_btree_init_block_cur(
1157 struct xfs_btree_cur *cur,
1165 * we can pull the owner from the cursor right now as the different
1166 * owners align directly with the pointer size of the btree. This may
1167 * change in future, but is safe for current users of the generic btree
1170 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
1171 owner = cur->bc_private.b.ip->i_ino;
1173 owner = cur->bc_private.a.agno;
1175 xfs_btree_init_block_int(cur->bc_mp, XFS_BUF_TO_BLOCK(bp), bp->b_bn,
1176 cur->bc_btnum, level, numrecs,
1177 owner, cur->bc_flags);
1181 * Return true if ptr is the last record in the btree and
1182 * we need to track updates to this record. The decision
1183 * will be further refined in the update_lastrec method.
1186 xfs_btree_is_lastrec(
1187 struct xfs_btree_cur *cur,
1188 struct xfs_btree_block *block,
1191 union xfs_btree_ptr ptr;
1195 if (!(cur->bc_flags & XFS_BTREE_LASTREC_UPDATE))
1198 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
1199 if (!xfs_btree_ptr_is_null(cur, &ptr))
1205 xfs_btree_buf_to_ptr(
1206 struct xfs_btree_cur *cur,
1208 union xfs_btree_ptr *ptr)
1210 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
1211 ptr->l = cpu_to_be64(XFS_DADDR_TO_FSB(cur->bc_mp,
1214 ptr->s = cpu_to_be32(xfs_daddr_to_agbno(cur->bc_mp,
1221 struct xfs_btree_cur *cur,
1224 switch (cur->bc_btnum) {
1227 xfs_buf_set_ref(bp, XFS_ALLOC_BTREE_REF);
1230 case XFS_BTNUM_FINO:
1231 xfs_buf_set_ref(bp, XFS_INO_BTREE_REF);
1233 case XFS_BTNUM_BMAP:
1234 xfs_buf_set_ref(bp, XFS_BMAP_BTREE_REF);
1236 case XFS_BTNUM_RMAP:
1237 xfs_buf_set_ref(bp, XFS_RMAP_BTREE_REF);
1239 case XFS_BTNUM_REFC:
1240 xfs_buf_set_ref(bp, XFS_REFC_BTREE_REF);
1248 xfs_btree_get_buf_block(
1249 struct xfs_btree_cur *cur,
1250 union xfs_btree_ptr *ptr,
1252 struct xfs_btree_block **block,
1253 struct xfs_buf **bpp)
1255 struct xfs_mount *mp = cur->bc_mp;
1258 /* need to sort out how callers deal with failures first */
1259 ASSERT(!(flags & XBF_TRYLOCK));
1261 d = xfs_btree_ptr_to_daddr(cur, ptr);
1262 *bpp = xfs_trans_get_buf(cur->bc_tp, mp->m_ddev_targp, d,
1263 mp->m_bsize, flags);
1268 (*bpp)->b_ops = cur->bc_ops->buf_ops;
1269 *block = XFS_BUF_TO_BLOCK(*bpp);
1274 * Read in the buffer at the given ptr and return the buffer and
1275 * the block pointer within the buffer.
1278 xfs_btree_read_buf_block(
1279 struct xfs_btree_cur *cur,
1280 union xfs_btree_ptr *ptr,
1282 struct xfs_btree_block **block,
1283 struct xfs_buf **bpp)
1285 struct xfs_mount *mp = cur->bc_mp;
1289 /* need to sort out how callers deal with failures first */
1290 ASSERT(!(flags & XBF_TRYLOCK));
1292 d = xfs_btree_ptr_to_daddr(cur, ptr);
1293 error = xfs_trans_read_buf(mp, cur->bc_tp, mp->m_ddev_targp, d,
1294 mp->m_bsize, flags, bpp,
1295 cur->bc_ops->buf_ops);
1299 xfs_btree_set_refs(cur, *bpp);
1300 *block = XFS_BUF_TO_BLOCK(*bpp);
1305 * Copy keys from one btree block to another.
1308 xfs_btree_copy_keys(
1309 struct xfs_btree_cur *cur,
1310 union xfs_btree_key *dst_key,
1311 union xfs_btree_key *src_key,
1314 ASSERT(numkeys >= 0);
1315 memcpy(dst_key, src_key, numkeys * cur->bc_ops->key_len);
1319 * Copy records from one btree block to another.
1322 xfs_btree_copy_recs(
1323 struct xfs_btree_cur *cur,
1324 union xfs_btree_rec *dst_rec,
1325 union xfs_btree_rec *src_rec,
1328 ASSERT(numrecs >= 0);
1329 memcpy(dst_rec, src_rec, numrecs * cur->bc_ops->rec_len);
1333 * Copy block pointers from one btree block to another.
1336 xfs_btree_copy_ptrs(
1337 struct xfs_btree_cur *cur,
1338 union xfs_btree_ptr *dst_ptr,
1339 union xfs_btree_ptr *src_ptr,
1342 ASSERT(numptrs >= 0);
1343 memcpy(dst_ptr, src_ptr, numptrs * xfs_btree_ptr_len(cur));
1347 * Shift keys one index left/right inside a single btree block.
1350 xfs_btree_shift_keys(
1351 struct xfs_btree_cur *cur,
1352 union xfs_btree_key *key,
1358 ASSERT(numkeys >= 0);
1359 ASSERT(dir == 1 || dir == -1);
1361 dst_key = (char *)key + (dir * cur->bc_ops->key_len);
1362 memmove(dst_key, key, numkeys * cur->bc_ops->key_len);
1366 * Shift records one index left/right inside a single btree block.
1369 xfs_btree_shift_recs(
1370 struct xfs_btree_cur *cur,
1371 union xfs_btree_rec *rec,
1377 ASSERT(numrecs >= 0);
1378 ASSERT(dir == 1 || dir == -1);
1380 dst_rec = (char *)rec + (dir * cur->bc_ops->rec_len);
1381 memmove(dst_rec, rec, numrecs * cur->bc_ops->rec_len);
1385 * Shift block pointers one index left/right inside a single btree block.
1388 xfs_btree_shift_ptrs(
1389 struct xfs_btree_cur *cur,
1390 union xfs_btree_ptr *ptr,
1396 ASSERT(numptrs >= 0);
1397 ASSERT(dir == 1 || dir == -1);
1399 dst_ptr = (char *)ptr + (dir * xfs_btree_ptr_len(cur));
1400 memmove(dst_ptr, ptr, numptrs * xfs_btree_ptr_len(cur));
1404 * Log key values from the btree block.
1408 struct xfs_btree_cur *cur,
1413 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1414 XFS_BTREE_TRACE_ARGBII(cur, bp, first, last);
1417 xfs_trans_buf_set_type(cur->bc_tp, bp, XFS_BLFT_BTREE_BUF);
1418 xfs_trans_log_buf(cur->bc_tp, bp,
1419 xfs_btree_key_offset(cur, first),
1420 xfs_btree_key_offset(cur, last + 1) - 1);
1422 xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip,
1423 xfs_ilog_fbroot(cur->bc_private.b.whichfork));
1426 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1430 * Log record values from the btree block.
1434 struct xfs_btree_cur *cur,
1439 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1440 XFS_BTREE_TRACE_ARGBII(cur, bp, first, last);
1442 xfs_trans_buf_set_type(cur->bc_tp, bp, XFS_BLFT_BTREE_BUF);
1443 xfs_trans_log_buf(cur->bc_tp, bp,
1444 xfs_btree_rec_offset(cur, first),
1445 xfs_btree_rec_offset(cur, last + 1) - 1);
1447 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1451 * Log block pointer fields from a btree block (nonleaf).
1455 struct xfs_btree_cur *cur, /* btree cursor */
1456 struct xfs_buf *bp, /* buffer containing btree block */
1457 int first, /* index of first pointer to log */
1458 int last) /* index of last pointer to log */
1460 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1461 XFS_BTREE_TRACE_ARGBII(cur, bp, first, last);
1464 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
1465 int level = xfs_btree_get_level(block);
1467 xfs_trans_buf_set_type(cur->bc_tp, bp, XFS_BLFT_BTREE_BUF);
1468 xfs_trans_log_buf(cur->bc_tp, bp,
1469 xfs_btree_ptr_offset(cur, first, level),
1470 xfs_btree_ptr_offset(cur, last + 1, level) - 1);
1472 xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip,
1473 xfs_ilog_fbroot(cur->bc_private.b.whichfork));
1476 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1480 * Log fields from a btree block header.
1483 xfs_btree_log_block(
1484 struct xfs_btree_cur *cur, /* btree cursor */
1485 struct xfs_buf *bp, /* buffer containing btree block */
1486 int fields) /* mask of fields: XFS_BB_... */
1488 int first; /* first byte offset logged */
1489 int last; /* last byte offset logged */
1490 static const short soffsets[] = { /* table of offsets (short) */
1491 offsetof(struct xfs_btree_block, bb_magic),
1492 offsetof(struct xfs_btree_block, bb_level),
1493 offsetof(struct xfs_btree_block, bb_numrecs),
1494 offsetof(struct xfs_btree_block, bb_u.s.bb_leftsib),
1495 offsetof(struct xfs_btree_block, bb_u.s.bb_rightsib),
1496 offsetof(struct xfs_btree_block, bb_u.s.bb_blkno),
1497 offsetof(struct xfs_btree_block, bb_u.s.bb_lsn),
1498 offsetof(struct xfs_btree_block, bb_u.s.bb_uuid),
1499 offsetof(struct xfs_btree_block, bb_u.s.bb_owner),
1500 offsetof(struct xfs_btree_block, bb_u.s.bb_crc),
1501 XFS_BTREE_SBLOCK_CRC_LEN
1503 static const short loffsets[] = { /* table of offsets (long) */
1504 offsetof(struct xfs_btree_block, bb_magic),
1505 offsetof(struct xfs_btree_block, bb_level),
1506 offsetof(struct xfs_btree_block, bb_numrecs),
1507 offsetof(struct xfs_btree_block, bb_u.l.bb_leftsib),
1508 offsetof(struct xfs_btree_block, bb_u.l.bb_rightsib),
1509 offsetof(struct xfs_btree_block, bb_u.l.bb_blkno),
1510 offsetof(struct xfs_btree_block, bb_u.l.bb_lsn),
1511 offsetof(struct xfs_btree_block, bb_u.l.bb_uuid),
1512 offsetof(struct xfs_btree_block, bb_u.l.bb_owner),
1513 offsetof(struct xfs_btree_block, bb_u.l.bb_crc),
1514 offsetof(struct xfs_btree_block, bb_u.l.bb_pad),
1515 XFS_BTREE_LBLOCK_CRC_LEN
1518 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1519 XFS_BTREE_TRACE_ARGBI(cur, bp, fields);
1524 if (cur->bc_flags & XFS_BTREE_CRC_BLOCKS) {
1526 * We don't log the CRC when updating a btree
1527 * block but instead recreate it during log
1528 * recovery. As the log buffers have checksums
1529 * of their own this is safe and avoids logging a crc
1530 * update in a lot of places.
1532 if (fields == XFS_BB_ALL_BITS)
1533 fields = XFS_BB_ALL_BITS_CRC;
1534 nbits = XFS_BB_NUM_BITS_CRC;
1536 nbits = XFS_BB_NUM_BITS;
1538 xfs_btree_offsets(fields,
1539 (cur->bc_flags & XFS_BTREE_LONG_PTRS) ?
1540 loffsets : soffsets,
1541 nbits, &first, &last);
1542 xfs_trans_buf_set_type(cur->bc_tp, bp, XFS_BLFT_BTREE_BUF);
1543 xfs_trans_log_buf(cur->bc_tp, bp, first, last);
1545 xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip,
1546 xfs_ilog_fbroot(cur->bc_private.b.whichfork));
1549 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1553 * Increment cursor by one record at the level.
1554 * For nonzero levels the leaf-ward information is untouched.
1557 xfs_btree_increment(
1558 struct xfs_btree_cur *cur,
1560 int *stat) /* success/failure */
1562 struct xfs_btree_block *block;
1563 union xfs_btree_ptr ptr;
1565 int error; /* error return value */
1568 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1569 XFS_BTREE_TRACE_ARGI(cur, level);
1571 ASSERT(level < cur->bc_nlevels);
1573 /* Read-ahead to the right at this level. */
1574 xfs_btree_readahead(cur, level, XFS_BTCUR_RIGHTRA);
1576 /* Get a pointer to the btree block. */
1577 block = xfs_btree_get_block(cur, level, &bp);
1580 error = xfs_btree_check_block(cur, block, level, bp);
1585 /* We're done if we remain in the block after the increment. */
1586 if (++cur->bc_ptrs[level] <= xfs_btree_get_numrecs(block))
1589 /* Fail if we just went off the right edge of the tree. */
1590 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
1591 if (xfs_btree_ptr_is_null(cur, &ptr))
1594 XFS_BTREE_STATS_INC(cur, increment);
1597 * March up the tree incrementing pointers.
1598 * Stop when we don't go off the right edge of a block.
1600 for (lev = level + 1; lev < cur->bc_nlevels; lev++) {
1601 block = xfs_btree_get_block(cur, lev, &bp);
1604 error = xfs_btree_check_block(cur, block, lev, bp);
1609 if (++cur->bc_ptrs[lev] <= xfs_btree_get_numrecs(block))
1612 /* Read-ahead the right block for the next loop. */
1613 xfs_btree_readahead(cur, lev, XFS_BTCUR_RIGHTRA);
1617 * If we went off the root then we are either seriously
1618 * confused or have the tree root in an inode.
1620 if (lev == cur->bc_nlevels) {
1621 if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE)
1624 error = -EFSCORRUPTED;
1627 ASSERT(lev < cur->bc_nlevels);
1630 * Now walk back down the tree, fixing up the cursor's buffer
1631 * pointers and key numbers.
1633 for (block = xfs_btree_get_block(cur, lev, &bp); lev > level; ) {
1634 union xfs_btree_ptr *ptrp;
1636 ptrp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[lev], block);
1638 error = xfs_btree_read_buf_block(cur, ptrp, 0, &block, &bp);
1642 xfs_btree_setbuf(cur, lev, bp);
1643 cur->bc_ptrs[lev] = 1;
1646 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1651 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1656 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
1661 * Decrement cursor by one record at the level.
1662 * For nonzero levels the leaf-ward information is untouched.
1665 xfs_btree_decrement(
1666 struct xfs_btree_cur *cur,
1668 int *stat) /* success/failure */
1670 struct xfs_btree_block *block;
1672 int error; /* error return value */
1674 union xfs_btree_ptr ptr;
1676 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1677 XFS_BTREE_TRACE_ARGI(cur, level);
1679 ASSERT(level < cur->bc_nlevels);
1681 /* Read-ahead to the left at this level. */
1682 xfs_btree_readahead(cur, level, XFS_BTCUR_LEFTRA);
1684 /* We're done if we remain in the block after the decrement. */
1685 if (--cur->bc_ptrs[level] > 0)
1688 /* Get a pointer to the btree block. */
1689 block = xfs_btree_get_block(cur, level, &bp);
1692 error = xfs_btree_check_block(cur, block, level, bp);
1697 /* Fail if we just went off the left edge of the tree. */
1698 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_LEFTSIB);
1699 if (xfs_btree_ptr_is_null(cur, &ptr))
1702 XFS_BTREE_STATS_INC(cur, decrement);
1705 * March up the tree decrementing pointers.
1706 * Stop when we don't go off the left edge of a block.
1708 for (lev = level + 1; lev < cur->bc_nlevels; lev++) {
1709 if (--cur->bc_ptrs[lev] > 0)
1711 /* Read-ahead the left block for the next loop. */
1712 xfs_btree_readahead(cur, lev, XFS_BTCUR_LEFTRA);
1716 * If we went off the root then we are seriously confused.
1717 * or the root of the tree is in an inode.
1719 if (lev == cur->bc_nlevels) {
1720 if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE)
1723 error = -EFSCORRUPTED;
1726 ASSERT(lev < cur->bc_nlevels);
1729 * Now walk back down the tree, fixing up the cursor's buffer
1730 * pointers and key numbers.
1732 for (block = xfs_btree_get_block(cur, lev, &bp); lev > level; ) {
1733 union xfs_btree_ptr *ptrp;
1735 ptrp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[lev], block);
1737 error = xfs_btree_read_buf_block(cur, ptrp, 0, &block, &bp);
1740 xfs_btree_setbuf(cur, lev, bp);
1741 cur->bc_ptrs[lev] = xfs_btree_get_numrecs(block);
1744 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1749 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1754 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
1759 xfs_btree_lookup_get_block(
1760 struct xfs_btree_cur *cur, /* btree cursor */
1761 int level, /* level in the btree */
1762 union xfs_btree_ptr *pp, /* ptr to btree block */
1763 struct xfs_btree_block **blkp) /* return btree block */
1765 struct xfs_buf *bp; /* buffer pointer for btree block */
1768 /* special case the root block if in an inode */
1769 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
1770 (level == cur->bc_nlevels - 1)) {
1771 *blkp = xfs_btree_get_iroot(cur);
1776 * If the old buffer at this level for the disk address we are
1777 * looking for re-use it.
1779 * Otherwise throw it away and get a new one.
1781 bp = cur->bc_bufs[level];
1782 if (bp && XFS_BUF_ADDR(bp) == xfs_btree_ptr_to_daddr(cur, pp)) {
1783 *blkp = XFS_BUF_TO_BLOCK(bp);
1787 error = xfs_btree_read_buf_block(cur, pp, 0, blkp, &bp);
1791 /* Check the inode owner since the verifiers don't. */
1792 if (xfs_sb_version_hascrc(&cur->bc_mp->m_sb) &&
1793 (cur->bc_flags & XFS_BTREE_LONG_PTRS) &&
1794 be64_to_cpu((*blkp)->bb_u.l.bb_owner) !=
1795 cur->bc_private.b.ip->i_ino)
1798 /* Did we get the level we were looking for? */
1799 if (be16_to_cpu((*blkp)->bb_level) != level)
1802 /* Check that internal nodes have at least one record. */
1803 if (level != 0 && be16_to_cpu((*blkp)->bb_numrecs) == 0)
1806 xfs_btree_setbuf(cur, level, bp);
1811 xfs_trans_brelse(cur->bc_tp, bp);
1812 return -EFSCORRUPTED;
1816 * Get current search key. For level 0 we don't actually have a key
1817 * structure so we make one up from the record. For all other levels
1818 * we just return the right key.
1820 STATIC union xfs_btree_key *
1821 xfs_lookup_get_search_key(
1822 struct xfs_btree_cur *cur,
1825 struct xfs_btree_block *block,
1826 union xfs_btree_key *kp)
1829 cur->bc_ops->init_key_from_rec(kp,
1830 xfs_btree_rec_addr(cur, keyno, block));
1834 return xfs_btree_key_addr(cur, keyno, block);
1838 * Lookup the record. The cursor is made to point to it, based on dir.
1839 * stat is set to 0 if can't find any such record, 1 for success.
1843 struct xfs_btree_cur *cur, /* btree cursor */
1844 xfs_lookup_t dir, /* <=, ==, or >= */
1845 int *stat) /* success/failure */
1847 struct xfs_btree_block *block; /* current btree block */
1848 __int64_t diff; /* difference for the current key */
1849 int error; /* error return value */
1850 int keyno; /* current key number */
1851 int level; /* level in the btree */
1852 union xfs_btree_ptr *pp; /* ptr to btree block */
1853 union xfs_btree_ptr ptr; /* ptr to btree block */
1855 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1856 XFS_BTREE_TRACE_ARGI(cur, dir);
1858 XFS_BTREE_STATS_INC(cur, lookup);
1860 /* No such thing as a zero-level tree. */
1861 if (cur->bc_nlevels == 0)
1862 return -EFSCORRUPTED;
1867 /* initialise start pointer from cursor */
1868 cur->bc_ops->init_ptr_from_cur(cur, &ptr);
1872 * Iterate over each level in the btree, starting at the root.
1873 * For each level above the leaves, find the key we need, based
1874 * on the lookup record, then follow the corresponding block
1875 * pointer down to the next level.
1877 for (level = cur->bc_nlevels - 1, diff = 1; level >= 0; level--) {
1878 /* Get the block we need to do the lookup on. */
1879 error = xfs_btree_lookup_get_block(cur, level, pp, &block);
1885 * If we already had a key match at a higher level, we
1886 * know we need to use the first entry in this block.
1890 /* Otherwise search this block. Do a binary search. */
1892 int high; /* high entry number */
1893 int low; /* low entry number */
1895 /* Set low and high entry numbers, 1-based. */
1897 high = xfs_btree_get_numrecs(block);
1899 /* Block is empty, must be an empty leaf. */
1900 ASSERT(level == 0 && cur->bc_nlevels == 1);
1902 cur->bc_ptrs[0] = dir != XFS_LOOKUP_LE;
1903 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1908 /* Binary search the block. */
1909 while (low <= high) {
1910 union xfs_btree_key key;
1911 union xfs_btree_key *kp;
1913 XFS_BTREE_STATS_INC(cur, compare);
1915 /* keyno is average of low and high. */
1916 keyno = (low + high) >> 1;
1918 /* Get current search key */
1919 kp = xfs_lookup_get_search_key(cur, level,
1920 keyno, block, &key);
1923 * Compute difference to get next direction:
1924 * - less than, move right
1925 * - greater than, move left
1926 * - equal, we're done
1928 diff = cur->bc_ops->key_diff(cur, kp);
1939 * If there are more levels, set up for the next level
1940 * by getting the block number and filling in the cursor.
1944 * If we moved left, need the previous key number,
1945 * unless there isn't one.
1947 if (diff > 0 && --keyno < 1)
1949 pp = xfs_btree_ptr_addr(cur, keyno, block);
1952 error = xfs_btree_check_ptr(cur, pp, 0, level);
1956 cur->bc_ptrs[level] = keyno;
1960 /* Done with the search. See if we need to adjust the results. */
1961 if (dir != XFS_LOOKUP_LE && diff < 0) {
1964 * If ge search and we went off the end of the block, but it's
1965 * not the last block, we're in the wrong block.
1967 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
1968 if (dir == XFS_LOOKUP_GE &&
1969 keyno > xfs_btree_get_numrecs(block) &&
1970 !xfs_btree_ptr_is_null(cur, &ptr)) {
1973 cur->bc_ptrs[0] = keyno;
1974 error = xfs_btree_increment(cur, 0, &i);
1977 XFS_WANT_CORRUPTED_RETURN(cur->bc_mp, i == 1);
1978 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1982 } else if (dir == XFS_LOOKUP_LE && diff > 0)
1984 cur->bc_ptrs[0] = keyno;
1986 /* Return if we succeeded or not. */
1987 if (keyno == 0 || keyno > xfs_btree_get_numrecs(block))
1989 else if (dir != XFS_LOOKUP_EQ || diff == 0)
1993 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1997 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2001 /* Find the high key storage area from a regular key. */
2002 STATIC union xfs_btree_key *
2003 xfs_btree_high_key_from_key(
2004 struct xfs_btree_cur *cur,
2005 union xfs_btree_key *key)
2007 ASSERT(cur->bc_flags & XFS_BTREE_OVERLAPPING);
2008 return (union xfs_btree_key *)((char *)key +
2009 (cur->bc_ops->key_len / 2));
2012 /* Determine the low (and high if overlapped) keys of a leaf block */
2014 xfs_btree_get_leaf_keys(
2015 struct xfs_btree_cur *cur,
2016 struct xfs_btree_block *block,
2017 union xfs_btree_key *key)
2019 union xfs_btree_key max_hkey;
2020 union xfs_btree_key hkey;
2021 union xfs_btree_rec *rec;
2022 union xfs_btree_key *high;
2025 rec = xfs_btree_rec_addr(cur, 1, block);
2026 cur->bc_ops->init_key_from_rec(key, rec);
2028 if (cur->bc_flags & XFS_BTREE_OVERLAPPING) {
2030 cur->bc_ops->init_high_key_from_rec(&max_hkey, rec);
2031 for (n = 2; n <= xfs_btree_get_numrecs(block); n++) {
2032 rec = xfs_btree_rec_addr(cur, n, block);
2033 cur->bc_ops->init_high_key_from_rec(&hkey, rec);
2034 if (cur->bc_ops->diff_two_keys(cur, &hkey, &max_hkey)
2039 high = xfs_btree_high_key_from_key(cur, key);
2040 memcpy(high, &max_hkey, cur->bc_ops->key_len / 2);
2044 /* Determine the low (and high if overlapped) keys of a node block */
2046 xfs_btree_get_node_keys(
2047 struct xfs_btree_cur *cur,
2048 struct xfs_btree_block *block,
2049 union xfs_btree_key *key)
2051 union xfs_btree_key *hkey;
2052 union xfs_btree_key *max_hkey;
2053 union xfs_btree_key *high;
2056 if (cur->bc_flags & XFS_BTREE_OVERLAPPING) {
2057 memcpy(key, xfs_btree_key_addr(cur, 1, block),
2058 cur->bc_ops->key_len / 2);
2060 max_hkey = xfs_btree_high_key_addr(cur, 1, block);
2061 for (n = 2; n <= xfs_btree_get_numrecs(block); n++) {
2062 hkey = xfs_btree_high_key_addr(cur, n, block);
2063 if (cur->bc_ops->diff_two_keys(cur, hkey, max_hkey) > 0)
2067 high = xfs_btree_high_key_from_key(cur, key);
2068 memcpy(high, max_hkey, cur->bc_ops->key_len / 2);
2070 memcpy(key, xfs_btree_key_addr(cur, 1, block),
2071 cur->bc_ops->key_len);
2075 /* Derive the keys for any btree block. */
2078 struct xfs_btree_cur *cur,
2079 struct xfs_btree_block *block,
2080 union xfs_btree_key *key)
2082 if (be16_to_cpu(block->bb_level) == 0)
2083 xfs_btree_get_leaf_keys(cur, block, key);
2085 xfs_btree_get_node_keys(cur, block, key);
2089 * Decide if we need to update the parent keys of a btree block. For
2090 * a standard btree this is only necessary if we're updating the first
2091 * record/key. For an overlapping btree, we must always update the
2092 * keys because the highest key can be in any of the records or keys
2096 xfs_btree_needs_key_update(
2097 struct xfs_btree_cur *cur,
2100 return (cur->bc_flags & XFS_BTREE_OVERLAPPING) || ptr == 1;
2104 * Update the low and high parent keys of the given level, progressing
2105 * towards the root. If force_all is false, stop if the keys for a given
2106 * level do not need updating.
2109 __xfs_btree_updkeys(
2110 struct xfs_btree_cur *cur,
2112 struct xfs_btree_block *block,
2113 struct xfs_buf *bp0,
2116 union xfs_btree_key key; /* keys from current level */
2117 union xfs_btree_key *lkey; /* keys from the next level up */
2118 union xfs_btree_key *hkey;
2119 union xfs_btree_key *nlkey; /* keys from the next level up */
2120 union xfs_btree_key *nhkey;
2124 ASSERT(cur->bc_flags & XFS_BTREE_OVERLAPPING);
2126 /* Exit if there aren't any parent levels to update. */
2127 if (level + 1 >= cur->bc_nlevels)
2130 trace_xfs_btree_updkeys(cur, level, bp0);
2133 hkey = xfs_btree_high_key_from_key(cur, lkey);
2134 xfs_btree_get_keys(cur, block, lkey);
2135 for (level++; level < cur->bc_nlevels; level++) {
2139 block = xfs_btree_get_block(cur, level, &bp);
2140 trace_xfs_btree_updkeys(cur, level, bp);
2142 error = xfs_btree_check_block(cur, block, level, bp);
2144 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2148 ptr = cur->bc_ptrs[level];
2149 nlkey = xfs_btree_key_addr(cur, ptr, block);
2150 nhkey = xfs_btree_high_key_addr(cur, ptr, block);
2152 !(cur->bc_ops->diff_two_keys(cur, nlkey, lkey) != 0 ||
2153 cur->bc_ops->diff_two_keys(cur, nhkey, hkey) != 0))
2155 xfs_btree_copy_keys(cur, nlkey, lkey, 1);
2156 xfs_btree_log_keys(cur, bp, ptr, ptr);
2157 if (level + 1 >= cur->bc_nlevels)
2159 xfs_btree_get_node_keys(cur, block, lkey);
2165 /* Update all the keys from some level in cursor back to the root. */
2167 xfs_btree_updkeys_force(
2168 struct xfs_btree_cur *cur,
2172 struct xfs_btree_block *block;
2174 block = xfs_btree_get_block(cur, level, &bp);
2175 return __xfs_btree_updkeys(cur, level, block, bp, true);
2179 * Update the parent keys of the given level, progressing towards the root.
2182 xfs_btree_update_keys(
2183 struct xfs_btree_cur *cur,
2186 struct xfs_btree_block *block;
2188 union xfs_btree_key *kp;
2189 union xfs_btree_key key;
2194 block = xfs_btree_get_block(cur, level, &bp);
2195 if (cur->bc_flags & XFS_BTREE_OVERLAPPING)
2196 return __xfs_btree_updkeys(cur, level, block, bp, false);
2198 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2199 XFS_BTREE_TRACE_ARGIK(cur, level, keyp);
2202 * Go up the tree from this level toward the root.
2203 * At each level, update the key value to the value input.
2204 * Stop when we reach a level where the cursor isn't pointing
2205 * at the first entry in the block.
2207 xfs_btree_get_keys(cur, block, &key);
2208 for (level++, ptr = 1; ptr == 1 && level < cur->bc_nlevels; level++) {
2212 block = xfs_btree_get_block(cur, level, &bp);
2214 error = xfs_btree_check_block(cur, block, level, bp);
2216 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2220 ptr = cur->bc_ptrs[level];
2221 kp = xfs_btree_key_addr(cur, ptr, block);
2222 xfs_btree_copy_keys(cur, kp, &key, 1);
2223 xfs_btree_log_keys(cur, bp, ptr, ptr);
2226 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2231 * Update the record referred to by cur to the value in the
2232 * given record. This either works (return 0) or gets an
2233 * EFSCORRUPTED error.
2237 struct xfs_btree_cur *cur,
2238 union xfs_btree_rec *rec)
2240 struct xfs_btree_block *block;
2244 union xfs_btree_rec *rp;
2246 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2247 XFS_BTREE_TRACE_ARGR(cur, rec);
2249 /* Pick up the current block. */
2250 block = xfs_btree_get_block(cur, 0, &bp);
2253 error = xfs_btree_check_block(cur, block, 0, bp);
2257 /* Get the address of the rec to be updated. */
2258 ptr = cur->bc_ptrs[0];
2259 rp = xfs_btree_rec_addr(cur, ptr, block);
2261 /* Fill in the new contents and log them. */
2262 xfs_btree_copy_recs(cur, rp, rec, 1);
2263 xfs_btree_log_recs(cur, bp, ptr, ptr);
2266 * If we are tracking the last record in the tree and
2267 * we are at the far right edge of the tree, update it.
2269 if (xfs_btree_is_lastrec(cur, block, 0)) {
2270 cur->bc_ops->update_lastrec(cur, block, rec,
2271 ptr, LASTREC_UPDATE);
2274 /* Pass new key value up to our parent. */
2275 if (xfs_btree_needs_key_update(cur, ptr)) {
2276 error = xfs_btree_update_keys(cur, 0);
2281 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2285 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2290 * Move 1 record left from cur/level if possible.
2291 * Update cur to reflect the new path.
2293 STATIC int /* error */
2295 struct xfs_btree_cur *cur,
2297 int *stat) /* success/failure */
2299 struct xfs_buf *lbp; /* left buffer pointer */
2300 struct xfs_btree_block *left; /* left btree block */
2301 int lrecs; /* left record count */
2302 struct xfs_buf *rbp; /* right buffer pointer */
2303 struct xfs_btree_block *right; /* right btree block */
2304 struct xfs_btree_cur *tcur; /* temporary btree cursor */
2305 int rrecs; /* right record count */
2306 union xfs_btree_ptr lptr; /* left btree pointer */
2307 union xfs_btree_key *rkp = NULL; /* right btree key */
2308 union xfs_btree_ptr *rpp = NULL; /* right address pointer */
2309 union xfs_btree_rec *rrp = NULL; /* right record pointer */
2310 int error; /* error return value */
2313 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2314 XFS_BTREE_TRACE_ARGI(cur, level);
2316 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
2317 level == cur->bc_nlevels - 1)
2320 /* Set up variables for this block as "right". */
2321 right = xfs_btree_get_block(cur, level, &rbp);
2324 error = xfs_btree_check_block(cur, right, level, rbp);
2329 /* If we've got no left sibling then we can't shift an entry left. */
2330 xfs_btree_get_sibling(cur, right, &lptr, XFS_BB_LEFTSIB);
2331 if (xfs_btree_ptr_is_null(cur, &lptr))
2335 * If the cursor entry is the one that would be moved, don't
2336 * do it... it's too complicated.
2338 if (cur->bc_ptrs[level] <= 1)
2341 /* Set up the left neighbor as "left". */
2342 error = xfs_btree_read_buf_block(cur, &lptr, 0, &left, &lbp);
2346 /* If it's full, it can't take another entry. */
2347 lrecs = xfs_btree_get_numrecs(left);
2348 if (lrecs == cur->bc_ops->get_maxrecs(cur, level))
2351 rrecs = xfs_btree_get_numrecs(right);
2354 * We add one entry to the left side and remove one for the right side.
2355 * Account for it here, the changes will be updated on disk and logged
2361 XFS_BTREE_STATS_INC(cur, lshift);
2362 XFS_BTREE_STATS_ADD(cur, moves, 1);
2365 * If non-leaf, copy a key and a ptr to the left block.
2366 * Log the changes to the left block.
2369 /* It's a non-leaf. Move keys and pointers. */
2370 union xfs_btree_key *lkp; /* left btree key */
2371 union xfs_btree_ptr *lpp; /* left address pointer */
2373 lkp = xfs_btree_key_addr(cur, lrecs, left);
2374 rkp = xfs_btree_key_addr(cur, 1, right);
2376 lpp = xfs_btree_ptr_addr(cur, lrecs, left);
2377 rpp = xfs_btree_ptr_addr(cur, 1, right);
2379 error = xfs_btree_check_ptr(cur, rpp, 0, level);
2383 xfs_btree_copy_keys(cur, lkp, rkp, 1);
2384 xfs_btree_copy_ptrs(cur, lpp, rpp, 1);
2386 xfs_btree_log_keys(cur, lbp, lrecs, lrecs);
2387 xfs_btree_log_ptrs(cur, lbp, lrecs, lrecs);
2389 ASSERT(cur->bc_ops->keys_inorder(cur,
2390 xfs_btree_key_addr(cur, lrecs - 1, left), lkp));
2392 /* It's a leaf. Move records. */
2393 union xfs_btree_rec *lrp; /* left record pointer */
2395 lrp = xfs_btree_rec_addr(cur, lrecs, left);
2396 rrp = xfs_btree_rec_addr(cur, 1, right);
2398 xfs_btree_copy_recs(cur, lrp, rrp, 1);
2399 xfs_btree_log_recs(cur, lbp, lrecs, lrecs);
2401 ASSERT(cur->bc_ops->recs_inorder(cur,
2402 xfs_btree_rec_addr(cur, lrecs - 1, left), lrp));
2405 xfs_btree_set_numrecs(left, lrecs);
2406 xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS);
2408 xfs_btree_set_numrecs(right, rrecs);
2409 xfs_btree_log_block(cur, rbp, XFS_BB_NUMRECS);
2412 * Slide the contents of right down one entry.
2414 XFS_BTREE_STATS_ADD(cur, moves, rrecs - 1);
2416 /* It's a nonleaf. operate on keys and ptrs */
2418 int i; /* loop index */
2420 for (i = 0; i < rrecs; i++) {
2421 error = xfs_btree_check_ptr(cur, rpp, i + 1, level);
2426 xfs_btree_shift_keys(cur,
2427 xfs_btree_key_addr(cur, 2, right),
2429 xfs_btree_shift_ptrs(cur,
2430 xfs_btree_ptr_addr(cur, 2, right),
2433 xfs_btree_log_keys(cur, rbp, 1, rrecs);
2434 xfs_btree_log_ptrs(cur, rbp, 1, rrecs);
2436 /* It's a leaf. operate on records */
2437 xfs_btree_shift_recs(cur,
2438 xfs_btree_rec_addr(cur, 2, right),
2440 xfs_btree_log_recs(cur, rbp, 1, rrecs);
2444 * Using a temporary cursor, update the parent key values of the
2445 * block on the left.
2447 if (cur->bc_flags & XFS_BTREE_OVERLAPPING) {
2448 error = xfs_btree_dup_cursor(cur, &tcur);
2451 i = xfs_btree_firstrec(tcur, level);
2452 XFS_WANT_CORRUPTED_GOTO(tcur->bc_mp, i == 1, error0);
2454 error = xfs_btree_decrement(tcur, level, &i);
2458 /* Update the parent high keys of the left block, if needed. */
2459 error = xfs_btree_update_keys(tcur, level);
2463 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
2466 /* Update the parent keys of the right block. */
2467 error = xfs_btree_update_keys(cur, level);
2471 /* Slide the cursor value left one. */
2472 cur->bc_ptrs[level]--;
2474 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2479 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2484 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2488 XFS_BTREE_TRACE_CURSOR(tcur, XBT_ERROR);
2489 xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
2494 * Move 1 record right from cur/level if possible.
2495 * Update cur to reflect the new path.
2497 STATIC int /* error */
2499 struct xfs_btree_cur *cur,
2501 int *stat) /* success/failure */
2503 struct xfs_buf *lbp; /* left buffer pointer */
2504 struct xfs_btree_block *left; /* left btree block */
2505 struct xfs_buf *rbp; /* right buffer pointer */
2506 struct xfs_btree_block *right; /* right btree block */
2507 struct xfs_btree_cur *tcur; /* temporary btree cursor */
2508 union xfs_btree_ptr rptr; /* right block pointer */
2509 union xfs_btree_key *rkp; /* right btree key */
2510 int rrecs; /* right record count */
2511 int lrecs; /* left record count */
2512 int error; /* error return value */
2513 int i; /* loop counter */
2515 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2516 XFS_BTREE_TRACE_ARGI(cur, level);
2518 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
2519 (level == cur->bc_nlevels - 1))
2522 /* Set up variables for this block as "left". */
2523 left = xfs_btree_get_block(cur, level, &lbp);
2526 error = xfs_btree_check_block(cur, left, level, lbp);
2531 /* If we've got no right sibling then we can't shift an entry right. */
2532 xfs_btree_get_sibling(cur, left, &rptr, XFS_BB_RIGHTSIB);
2533 if (xfs_btree_ptr_is_null(cur, &rptr))
2537 * If the cursor entry is the one that would be moved, don't
2538 * do it... it's too complicated.
2540 lrecs = xfs_btree_get_numrecs(left);
2541 if (cur->bc_ptrs[level] >= lrecs)
2544 /* Set up the right neighbor as "right". */
2545 error = xfs_btree_read_buf_block(cur, &rptr, 0, &right, &rbp);
2549 /* If it's full, it can't take another entry. */
2550 rrecs = xfs_btree_get_numrecs(right);
2551 if (rrecs == cur->bc_ops->get_maxrecs(cur, level))
2554 XFS_BTREE_STATS_INC(cur, rshift);
2555 XFS_BTREE_STATS_ADD(cur, moves, rrecs);
2558 * Make a hole at the start of the right neighbor block, then
2559 * copy the last left block entry to the hole.
2562 /* It's a nonleaf. make a hole in the keys and ptrs */
2563 union xfs_btree_key *lkp;
2564 union xfs_btree_ptr *lpp;
2565 union xfs_btree_ptr *rpp;
2567 lkp = xfs_btree_key_addr(cur, lrecs, left);
2568 lpp = xfs_btree_ptr_addr(cur, lrecs, left);
2569 rkp = xfs_btree_key_addr(cur, 1, right);
2570 rpp = xfs_btree_ptr_addr(cur, 1, right);
2573 for (i = rrecs - 1; i >= 0; i--) {
2574 error = xfs_btree_check_ptr(cur, rpp, i, level);
2580 xfs_btree_shift_keys(cur, rkp, 1, rrecs);
2581 xfs_btree_shift_ptrs(cur, rpp, 1, rrecs);
2584 error = xfs_btree_check_ptr(cur, lpp, 0, level);
2589 /* Now put the new data in, and log it. */
2590 xfs_btree_copy_keys(cur, rkp, lkp, 1);
2591 xfs_btree_copy_ptrs(cur, rpp, lpp, 1);
2593 xfs_btree_log_keys(cur, rbp, 1, rrecs + 1);
2594 xfs_btree_log_ptrs(cur, rbp, 1, rrecs + 1);
2596 ASSERT(cur->bc_ops->keys_inorder(cur, rkp,
2597 xfs_btree_key_addr(cur, 2, right)));
2599 /* It's a leaf. make a hole in the records */
2600 union xfs_btree_rec *lrp;
2601 union xfs_btree_rec *rrp;
2603 lrp = xfs_btree_rec_addr(cur, lrecs, left);
2604 rrp = xfs_btree_rec_addr(cur, 1, right);
2606 xfs_btree_shift_recs(cur, rrp, 1, rrecs);
2608 /* Now put the new data in, and log it. */
2609 xfs_btree_copy_recs(cur, rrp, lrp, 1);
2610 xfs_btree_log_recs(cur, rbp, 1, rrecs + 1);
2614 * Decrement and log left's numrecs, bump and log right's numrecs.
2616 xfs_btree_set_numrecs(left, --lrecs);
2617 xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS);
2619 xfs_btree_set_numrecs(right, ++rrecs);
2620 xfs_btree_log_block(cur, rbp, XFS_BB_NUMRECS);
2623 * Using a temporary cursor, update the parent key values of the
2624 * block on the right.
2626 error = xfs_btree_dup_cursor(cur, &tcur);
2629 i = xfs_btree_lastrec(tcur, level);
2630 XFS_WANT_CORRUPTED_GOTO(tcur->bc_mp, i == 1, error0);
2632 error = xfs_btree_increment(tcur, level, &i);
2636 /* Update the parent high keys of the left block, if needed. */
2637 if (cur->bc_flags & XFS_BTREE_OVERLAPPING) {
2638 error = xfs_btree_update_keys(cur, level);
2643 /* Update the parent keys of the right block. */
2644 error = xfs_btree_update_keys(tcur, level);
2648 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
2650 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2655 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2660 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2664 XFS_BTREE_TRACE_CURSOR(tcur, XBT_ERROR);
2665 xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
2670 * Split cur/level block in half.
2671 * Return new block number and the key to its first
2672 * record (to be inserted into parent).
2674 STATIC int /* error */
2676 struct xfs_btree_cur *cur,
2678 union xfs_btree_ptr *ptrp,
2679 union xfs_btree_key *key,
2680 struct xfs_btree_cur **curp,
2681 int *stat) /* success/failure */
2683 union xfs_btree_ptr lptr; /* left sibling block ptr */
2684 struct xfs_buf *lbp; /* left buffer pointer */
2685 struct xfs_btree_block *left; /* left btree block */
2686 union xfs_btree_ptr rptr; /* right sibling block ptr */
2687 struct xfs_buf *rbp; /* right buffer pointer */
2688 struct xfs_btree_block *right; /* right btree block */
2689 union xfs_btree_ptr rrptr; /* right-right sibling ptr */
2690 struct xfs_buf *rrbp; /* right-right buffer pointer */
2691 struct xfs_btree_block *rrblock; /* right-right btree block */
2695 int error; /* error return value */
2700 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2701 XFS_BTREE_TRACE_ARGIPK(cur, level, *ptrp, key);
2703 XFS_BTREE_STATS_INC(cur, split);
2705 /* Set up left block (current one). */
2706 left = xfs_btree_get_block(cur, level, &lbp);
2709 error = xfs_btree_check_block(cur, left, level, lbp);
2714 xfs_btree_buf_to_ptr(cur, lbp, &lptr);
2716 /* Allocate the new block. If we can't do it, we're toast. Give up. */
2717 error = cur->bc_ops->alloc_block(cur, &lptr, &rptr, stat);
2722 XFS_BTREE_STATS_INC(cur, alloc);
2724 /* Set up the new block as "right". */
2725 error = xfs_btree_get_buf_block(cur, &rptr, 0, &right, &rbp);
2729 /* Fill in the btree header for the new right block. */
2730 xfs_btree_init_block_cur(cur, rbp, xfs_btree_get_level(left), 0);
2733 * Split the entries between the old and the new block evenly.
2734 * Make sure that if there's an odd number of entries now, that
2735 * each new block will have the same number of entries.
2737 lrecs = xfs_btree_get_numrecs(left);
2739 if ((lrecs & 1) && cur->bc_ptrs[level] <= rrecs + 1)
2741 src_index = (lrecs - rrecs + 1);
2743 XFS_BTREE_STATS_ADD(cur, moves, rrecs);
2745 /* Adjust numrecs for the later get_*_keys() calls. */
2747 xfs_btree_set_numrecs(left, lrecs);
2748 xfs_btree_set_numrecs(right, xfs_btree_get_numrecs(right) + rrecs);
2751 * Copy btree block entries from the left block over to the
2752 * new block, the right. Update the right block and log the
2756 /* It's a non-leaf. Move keys and pointers. */
2757 union xfs_btree_key *lkp; /* left btree key */
2758 union xfs_btree_ptr *lpp; /* left address pointer */
2759 union xfs_btree_key *rkp; /* right btree key */
2760 union xfs_btree_ptr *rpp; /* right address pointer */
2762 lkp = xfs_btree_key_addr(cur, src_index, left);
2763 lpp = xfs_btree_ptr_addr(cur, src_index, left);
2764 rkp = xfs_btree_key_addr(cur, 1, right);
2765 rpp = xfs_btree_ptr_addr(cur, 1, right);
2768 for (i = src_index; i < rrecs; i++) {
2769 error = xfs_btree_check_ptr(cur, lpp, i, level);
2775 /* Copy the keys & pointers to the new block. */
2776 xfs_btree_copy_keys(cur, rkp, lkp, rrecs);
2777 xfs_btree_copy_ptrs(cur, rpp, lpp, rrecs);
2779 xfs_btree_log_keys(cur, rbp, 1, rrecs);
2780 xfs_btree_log_ptrs(cur, rbp, 1, rrecs);
2782 /* Stash the keys of the new block for later insertion. */
2783 xfs_btree_get_node_keys(cur, right, key);
2785 /* It's a leaf. Move records. */
2786 union xfs_btree_rec *lrp; /* left record pointer */
2787 union xfs_btree_rec *rrp; /* right record pointer */
2789 lrp = xfs_btree_rec_addr(cur, src_index, left);
2790 rrp = xfs_btree_rec_addr(cur, 1, right);
2792 /* Copy records to the new block. */
2793 xfs_btree_copy_recs(cur, rrp, lrp, rrecs);
2794 xfs_btree_log_recs(cur, rbp, 1, rrecs);
2796 /* Stash the keys of the new block for later insertion. */
2797 xfs_btree_get_leaf_keys(cur, right, key);
2801 * Find the left block number by looking in the buffer.
2802 * Adjust sibling pointers.
2804 xfs_btree_get_sibling(cur, left, &rrptr, XFS_BB_RIGHTSIB);
2805 xfs_btree_set_sibling(cur, right, &rrptr, XFS_BB_RIGHTSIB);
2806 xfs_btree_set_sibling(cur, right, &lptr, XFS_BB_LEFTSIB);
2807 xfs_btree_set_sibling(cur, left, &rptr, XFS_BB_RIGHTSIB);
2809 xfs_btree_log_block(cur, rbp, XFS_BB_ALL_BITS);
2810 xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS | XFS_BB_RIGHTSIB);
2813 * If there's a block to the new block's right, make that block
2814 * point back to right instead of to left.
2816 if (!xfs_btree_ptr_is_null(cur, &rrptr)) {
2817 error = xfs_btree_read_buf_block(cur, &rrptr,
2818 0, &rrblock, &rrbp);
2821 xfs_btree_set_sibling(cur, rrblock, &rptr, XFS_BB_LEFTSIB);
2822 xfs_btree_log_block(cur, rrbp, XFS_BB_LEFTSIB);
2825 /* Update the parent high keys of the left block, if needed. */
2826 if (cur->bc_flags & XFS_BTREE_OVERLAPPING) {
2827 error = xfs_btree_update_keys(cur, level);
2833 * If the cursor is really in the right block, move it there.
2834 * If it's just pointing past the last entry in left, then we'll
2835 * insert there, so don't change anything in that case.
2837 if (cur->bc_ptrs[level] > lrecs + 1) {
2838 xfs_btree_setbuf(cur, level, rbp);
2839 cur->bc_ptrs[level] -= lrecs;
2842 * If there are more levels, we'll need another cursor which refers
2843 * the right block, no matter where this cursor was.
2845 if (level + 1 < cur->bc_nlevels) {
2846 error = xfs_btree_dup_cursor(cur, curp);
2849 (*curp)->bc_ptrs[level + 1]++;
2852 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2856 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2861 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2865 struct xfs_btree_split_args {
2866 struct xfs_btree_cur *cur;
2868 union xfs_btree_ptr *ptrp;
2869 union xfs_btree_key *key;
2870 struct xfs_btree_cur **curp;
2871 int *stat; /* success/failure */
2873 bool kswapd; /* allocation in kswapd context */
2874 struct completion *done;
2875 struct work_struct work;
2879 * Stack switching interfaces for allocation
2882 xfs_btree_split_worker(
2883 struct work_struct *work)
2885 struct xfs_btree_split_args *args = container_of(work,
2886 struct xfs_btree_split_args, work);
2887 unsigned long pflags;
2888 unsigned long new_pflags = PF_FSTRANS;
2891 * we are in a transaction context here, but may also be doing work
2892 * in kswapd context, and hence we may need to inherit that state
2893 * temporarily to ensure that we don't block waiting for memory reclaim
2897 new_pflags |= PF_MEMALLOC | PF_SWAPWRITE | PF_KSWAPD;
2899 current_set_flags_nested(&pflags, new_pflags);
2901 args->result = __xfs_btree_split(args->cur, args->level, args->ptrp,
2902 args->key, args->curp, args->stat);
2903 complete(args->done);
2905 current_restore_flags_nested(&pflags, new_pflags);
2909 * BMBT split requests often come in with little stack to work on. Push
2910 * them off to a worker thread so there is lots of stack to use. For the other
2911 * btree types, just call directly to avoid the context switch overhead here.
2913 STATIC int /* error */
2915 struct xfs_btree_cur *cur,
2917 union xfs_btree_ptr *ptrp,
2918 union xfs_btree_key *key,
2919 struct xfs_btree_cur **curp,
2920 int *stat) /* success/failure */
2922 struct xfs_btree_split_args args;
2923 DECLARE_COMPLETION_ONSTACK(done);
2925 if (cur->bc_btnum != XFS_BTNUM_BMAP)
2926 return __xfs_btree_split(cur, level, ptrp, key, curp, stat);
2935 args.kswapd = current_is_kswapd();
2936 INIT_WORK_ONSTACK(&args.work, xfs_btree_split_worker);
2937 queue_work(xfs_alloc_wq, &args.work);
2938 wait_for_completion(&done);
2939 destroy_work_on_stack(&args.work);
2945 * Copy the old inode root contents into a real block and make the
2946 * broot point to it.
2949 xfs_btree_new_iroot(
2950 struct xfs_btree_cur *cur, /* btree cursor */
2951 int *logflags, /* logging flags for inode */
2952 int *stat) /* return status - 0 fail */
2954 struct xfs_buf *cbp; /* buffer for cblock */
2955 struct xfs_btree_block *block; /* btree block */
2956 struct xfs_btree_block *cblock; /* child btree block */
2957 union xfs_btree_key *ckp; /* child key pointer */
2958 union xfs_btree_ptr *cpp; /* child ptr pointer */
2959 union xfs_btree_key *kp; /* pointer to btree key */
2960 union xfs_btree_ptr *pp; /* pointer to block addr */
2961 union xfs_btree_ptr nptr; /* new block addr */
2962 int level; /* btree level */
2963 int error; /* error return code */
2965 int i; /* loop counter */
2968 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2969 XFS_BTREE_STATS_INC(cur, newroot);
2971 ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE);
2973 level = cur->bc_nlevels - 1;
2975 block = xfs_btree_get_iroot(cur);
2976 pp = xfs_btree_ptr_addr(cur, 1, block);
2978 /* Allocate the new block. If we can't do it, we're toast. Give up. */
2979 error = cur->bc_ops->alloc_block(cur, pp, &nptr, stat);
2983 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2986 XFS_BTREE_STATS_INC(cur, alloc);
2988 /* Copy the root into a real block. */
2989 error = xfs_btree_get_buf_block(cur, &nptr, 0, &cblock, &cbp);
2994 * we can't just memcpy() the root in for CRC enabled btree blocks.
2995 * In that case have to also ensure the blkno remains correct
2997 memcpy(cblock, block, xfs_btree_block_len(cur));
2998 if (cur->bc_flags & XFS_BTREE_CRC_BLOCKS) {
2999 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
3000 cblock->bb_u.l.bb_blkno = cpu_to_be64(cbp->b_bn);
3002 cblock->bb_u.s.bb_blkno = cpu_to_be64(cbp->b_bn);
3005 be16_add_cpu(&block->bb_level, 1);
3006 xfs_btree_set_numrecs(block, 1);
3008 cur->bc_ptrs[level + 1] = 1;
3010 kp = xfs_btree_key_addr(cur, 1, block);
3011 ckp = xfs_btree_key_addr(cur, 1, cblock);
3012 xfs_btree_copy_keys(cur, ckp, kp, xfs_btree_get_numrecs(cblock));
3014 cpp = xfs_btree_ptr_addr(cur, 1, cblock);
3016 for (i = 0; i < be16_to_cpu(cblock->bb_numrecs); i++) {
3017 error = xfs_btree_check_ptr(cur, pp, i, level);
3022 xfs_btree_copy_ptrs(cur, cpp, pp, xfs_btree_get_numrecs(cblock));
3025 error = xfs_btree_check_ptr(cur, &nptr, 0, level);
3029 xfs_btree_copy_ptrs(cur, pp, &nptr, 1);
3031 xfs_iroot_realloc(cur->bc_private.b.ip,
3032 1 - xfs_btree_get_numrecs(cblock),
3033 cur->bc_private.b.whichfork);
3035 xfs_btree_setbuf(cur, level, cbp);
3038 * Do all this logging at the end so that
3039 * the root is at the right level.
3041 xfs_btree_log_block(cur, cbp, XFS_BB_ALL_BITS);
3042 xfs_btree_log_keys(cur, cbp, 1, be16_to_cpu(cblock->bb_numrecs));
3043 xfs_btree_log_ptrs(cur, cbp, 1, be16_to_cpu(cblock->bb_numrecs));
3046 XFS_ILOG_CORE | xfs_ilog_fbroot(cur->bc_private.b.whichfork);
3048 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3051 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3056 * Allocate a new root block, fill it in.
3058 STATIC int /* error */
3060 struct xfs_btree_cur *cur, /* btree cursor */
3061 int *stat) /* success/failure */
3063 struct xfs_btree_block *block; /* one half of the old root block */
3064 struct xfs_buf *bp; /* buffer containing block */
3065 int error; /* error return value */
3066 struct xfs_buf *lbp; /* left buffer pointer */
3067 struct xfs_btree_block *left; /* left btree block */
3068 struct xfs_buf *nbp; /* new (root) buffer */
3069 struct xfs_btree_block *new; /* new (root) btree block */
3070 int nptr; /* new value for key index, 1 or 2 */
3071 struct xfs_buf *rbp; /* right buffer pointer */
3072 struct xfs_btree_block *right; /* right btree block */
3073 union xfs_btree_ptr rptr;
3074 union xfs_btree_ptr lptr;
3076 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
3077 XFS_BTREE_STATS_INC(cur, newroot);
3079 /* initialise our start point from the cursor */
3080 cur->bc_ops->init_ptr_from_cur(cur, &rptr);
3082 /* Allocate the new block. If we can't do it, we're toast. Give up. */
3083 error = cur->bc_ops->alloc_block(cur, &rptr, &lptr, stat);
3088 XFS_BTREE_STATS_INC(cur, alloc);
3090 /* Set up the new block. */
3091 error = xfs_btree_get_buf_block(cur, &lptr, 0, &new, &nbp);
3095 /* Set the root in the holding structure increasing the level by 1. */
3096 cur->bc_ops->set_root(cur, &lptr, 1);
3099 * At the previous root level there are now two blocks: the old root,
3100 * and the new block generated when it was split. We don't know which
3101 * one the cursor is pointing at, so we set up variables "left" and
3102 * "right" for each case.
3104 block = xfs_btree_get_block(cur, cur->bc_nlevels - 1, &bp);
3107 error = xfs_btree_check_block(cur, block, cur->bc_nlevels - 1, bp);
3112 xfs_btree_get_sibling(cur, block, &rptr, XFS_BB_RIGHTSIB);
3113 if (!xfs_btree_ptr_is_null(cur, &rptr)) {
3114 /* Our block is left, pick up the right block. */
3116 xfs_btree_buf_to_ptr(cur, lbp, &lptr);
3118 error = xfs_btree_read_buf_block(cur, &rptr, 0, &right, &rbp);
3124 /* Our block is right, pick up the left block. */
3126 xfs_btree_buf_to_ptr(cur, rbp, &rptr);
3128 xfs_btree_get_sibling(cur, right, &lptr, XFS_BB_LEFTSIB);
3129 error = xfs_btree_read_buf_block(cur, &lptr, 0, &left, &lbp);
3136 /* Fill in the new block's btree header and log it. */
3137 xfs_btree_init_block_cur(cur, nbp, cur->bc_nlevels, 2);
3138 xfs_btree_log_block(cur, nbp, XFS_BB_ALL_BITS);
3139 ASSERT(!xfs_btree_ptr_is_null(cur, &lptr) &&
3140 !xfs_btree_ptr_is_null(cur, &rptr));
3142 /* Fill in the key data in the new root. */
3143 if (xfs_btree_get_level(left) > 0) {
3145 * Get the keys for the left block's keys and put them directly
3146 * in the parent block. Do the same for the right block.
3148 xfs_btree_get_node_keys(cur, left,
3149 xfs_btree_key_addr(cur, 1, new));
3150 xfs_btree_get_node_keys(cur, right,
3151 xfs_btree_key_addr(cur, 2, new));
3154 * Get the keys for the left block's records and put them
3155 * directly in the parent block. Do the same for the right
3158 xfs_btree_get_leaf_keys(cur, left,
3159 xfs_btree_key_addr(cur, 1, new));
3160 xfs_btree_get_leaf_keys(cur, right,
3161 xfs_btree_key_addr(cur, 2, new));
3163 xfs_btree_log_keys(cur, nbp, 1, 2);
3165 /* Fill in the pointer data in the new root. */
3166 xfs_btree_copy_ptrs(cur,
3167 xfs_btree_ptr_addr(cur, 1, new), &lptr, 1);
3168 xfs_btree_copy_ptrs(cur,
3169 xfs_btree_ptr_addr(cur, 2, new), &rptr, 1);
3170 xfs_btree_log_ptrs(cur, nbp, 1, 2);
3172 /* Fix up the cursor. */
3173 xfs_btree_setbuf(cur, cur->bc_nlevels, nbp);
3174 cur->bc_ptrs[cur->bc_nlevels] = nptr;
3176 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3180 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3183 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3189 xfs_btree_make_block_unfull(
3190 struct xfs_btree_cur *cur, /* btree cursor */
3191 int level, /* btree level */
3192 int numrecs,/* # of recs in block */
3193 int *oindex,/* old tree index */
3194 int *index, /* new tree index */
3195 union xfs_btree_ptr *nptr, /* new btree ptr */
3196 struct xfs_btree_cur **ncur, /* new btree cursor */
3197 union xfs_btree_key *key, /* key of new block */
3202 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
3203 level == cur->bc_nlevels - 1) {
3204 struct xfs_inode *ip = cur->bc_private.b.ip;
3206 if (numrecs < cur->bc_ops->get_dmaxrecs(cur, level)) {
3207 /* A root block that can be made bigger. */
3208 xfs_iroot_realloc(ip, 1, cur->bc_private.b.whichfork);
3211 /* A root block that needs replacing */
3214 error = xfs_btree_new_iroot(cur, &logflags, stat);
3215 if (error || *stat == 0)
3218 xfs_trans_log_inode(cur->bc_tp, ip, logflags);
3224 /* First, try shifting an entry to the right neighbor. */
3225 error = xfs_btree_rshift(cur, level, stat);
3229 /* Next, try shifting an entry to the left neighbor. */
3230 error = xfs_btree_lshift(cur, level, stat);
3235 *oindex = *index = cur->bc_ptrs[level];
3240 * Next, try splitting the current block in half.
3242 * If this works we have to re-set our variables because we
3243 * could be in a different block now.
3245 error = xfs_btree_split(cur, level, nptr, key, ncur, stat);
3246 if (error || *stat == 0)
3250 *index = cur->bc_ptrs[level];
3255 * Insert one record/level. Return information to the caller
3256 * allowing the next level up to proceed if necessary.
3260 struct xfs_btree_cur *cur, /* btree cursor */
3261 int level, /* level to insert record at */
3262 union xfs_btree_ptr *ptrp, /* i/o: block number inserted */
3263 union xfs_btree_rec *rec, /* record to insert */
3264 union xfs_btree_key *key, /* i/o: block key for ptrp */
3265 struct xfs_btree_cur **curp, /* output: new cursor replacing cur */
3266 int *stat) /* success/failure */
3268 struct xfs_btree_block *block; /* btree block */
3269 struct xfs_buf *bp; /* buffer for block */
3270 union xfs_btree_ptr nptr; /* new block ptr */
3271 struct xfs_btree_cur *ncur; /* new btree cursor */
3272 union xfs_btree_key nkey; /* new block key */
3273 union xfs_btree_key *lkey;
3274 int optr; /* old key/record index */
3275 int ptr; /* key/record index */
3276 int numrecs;/* number of records */
3277 int error; /* error return value */
3283 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
3284 XFS_BTREE_TRACE_ARGIPR(cur, level, *ptrp, &rec);
3290 * If we have an external root pointer, and we've made it to the
3291 * root level, allocate a new root block and we're done.
3293 if (!(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
3294 (level >= cur->bc_nlevels)) {
3295 error = xfs_btree_new_root(cur, stat);
3296 xfs_btree_set_ptr_null(cur, ptrp);
3298 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3302 /* If we're off the left edge, return failure. */
3303 ptr = cur->bc_ptrs[level];
3305 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3312 XFS_BTREE_STATS_INC(cur, insrec);
3314 /* Get pointers to the btree buffer and block. */
3315 block = xfs_btree_get_block(cur, level, &bp);
3316 old_bn = bp ? bp->b_bn : XFS_BUF_DADDR_NULL;
3317 numrecs = xfs_btree_get_numrecs(block);
3320 error = xfs_btree_check_block(cur, block, level, bp);
3324 /* Check that the new entry is being inserted in the right place. */
3325 if (ptr <= numrecs) {
3327 ASSERT(cur->bc_ops->recs_inorder(cur, rec,
3328 xfs_btree_rec_addr(cur, ptr, block)));
3330 ASSERT(cur->bc_ops->keys_inorder(cur, key,
3331 xfs_btree_key_addr(cur, ptr, block)));
3337 * If the block is full, we can't insert the new entry until we
3338 * make the block un-full.
3340 xfs_btree_set_ptr_null(cur, &nptr);
3341 if (numrecs == cur->bc_ops->get_maxrecs(cur, level)) {
3342 error = xfs_btree_make_block_unfull(cur, level, numrecs,
3343 &optr, &ptr, &nptr, &ncur, lkey, stat);
3344 if (error || *stat == 0)
3349 * The current block may have changed if the block was
3350 * previously full and we have just made space in it.
3352 block = xfs_btree_get_block(cur, level, &bp);
3353 numrecs = xfs_btree_get_numrecs(block);
3356 error = xfs_btree_check_block(cur, block, level, bp);
3362 * At this point we know there's room for our new entry in the block
3363 * we're pointing at.
3365 XFS_BTREE_STATS_ADD(cur, moves, numrecs - ptr + 1);
3368 /* It's a nonleaf. make a hole in the keys and ptrs */
3369 union xfs_btree_key *kp;
3370 union xfs_btree_ptr *pp;
3372 kp = xfs_btree_key_addr(cur, ptr, block);
3373 pp = xfs_btree_ptr_addr(cur, ptr, block);
3376 for (i = numrecs - ptr; i >= 0; i--) {
3377 error = xfs_btree_check_ptr(cur, pp, i, level);
3383 xfs_btree_shift_keys(cur, kp, 1, numrecs - ptr + 1);
3384 xfs_btree_shift_ptrs(cur, pp, 1, numrecs - ptr + 1);
3387 error = xfs_btree_check_ptr(cur, ptrp, 0, level);
3392 /* Now put the new data in, bump numrecs and log it. */
3393 xfs_btree_copy_keys(cur, kp, key, 1);
3394 xfs_btree_copy_ptrs(cur, pp, ptrp, 1);
3396 xfs_btree_set_numrecs(block, numrecs);
3397 xfs_btree_log_ptrs(cur, bp, ptr, numrecs);
3398 xfs_btree_log_keys(cur, bp, ptr, numrecs);
3400 if (ptr < numrecs) {
3401 ASSERT(cur->bc_ops->keys_inorder(cur, kp,
3402 xfs_btree_key_addr(cur, ptr + 1, block)));
3406 /* It's a leaf. make a hole in the records */
3407 union xfs_btree_rec *rp;
3409 rp = xfs_btree_rec_addr(cur, ptr, block);
3411 xfs_btree_shift_recs(cur, rp, 1, numrecs - ptr + 1);
3413 /* Now put the new data in, bump numrecs and log it. */
3414 xfs_btree_copy_recs(cur, rp, rec, 1);
3415 xfs_btree_set_numrecs(block, ++numrecs);
3416 xfs_btree_log_recs(cur, bp, ptr, numrecs);
3418 if (ptr < numrecs) {
3419 ASSERT(cur->bc_ops->recs_inorder(cur, rp,
3420 xfs_btree_rec_addr(cur, ptr + 1, block)));
3425 /* Log the new number of records in the btree header. */
3426 xfs_btree_log_block(cur, bp, XFS_BB_NUMRECS);
3429 * If we just inserted into a new tree block, we have to
3430 * recalculate nkey here because nkey is out of date.
3432 * Otherwise we're just updating an existing block (having shoved
3433 * some records into the new tree block), so use the regular key
3436 if (bp && bp->b_bn != old_bn) {
3437 xfs_btree_get_keys(cur, block, lkey);
3438 } else if (xfs_btree_needs_key_update(cur, optr)) {
3439 error = xfs_btree_update_keys(cur, level);
3445 * If we are tracking the last record in the tree and
3446 * we are at the far right edge of the tree, update it.
3448 if (xfs_btree_is_lastrec(cur, block, level)) {
3449 cur->bc_ops->update_lastrec(cur, block, rec,
3450 ptr, LASTREC_INSREC);
3454 * Return the new block number, if any.
3455 * If there is one, give back a record value and a cursor too.
3458 if (!xfs_btree_ptr_is_null(cur, &nptr)) {
3459 xfs_btree_copy_keys(cur, key, lkey, 1);
3463 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3468 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3473 * Insert the record at the point referenced by cur.
3475 * A multi-level split of the tree on insert will invalidate the original
3476 * cursor. All callers of this function should assume that the cursor is
3477 * no longer valid and revalidate it.
3481 struct xfs_btree_cur *cur,
3484 int error; /* error return value */
3485 int i; /* result value, 0 for failure */
3486 int level; /* current level number in btree */
3487 union xfs_btree_ptr nptr; /* new block number (split result) */
3488 struct xfs_btree_cur *ncur; /* new cursor (split result) */
3489 struct xfs_btree_cur *pcur; /* previous level's cursor */
3490 union xfs_btree_key bkey; /* key of block to insert */
3491 union xfs_btree_key *key;
3492 union xfs_btree_rec rec; /* record to insert */
3499 xfs_btree_set_ptr_null(cur, &nptr);
3501 /* Make a key out of the record data to be inserted, and save it. */
3502 cur->bc_ops->init_rec_from_cur(cur, &rec);
3503 cur->bc_ops->init_key_from_rec(key, &rec);
3506 * Loop going up the tree, starting at the leaf level.
3507 * Stop when we don't get a split block, that must mean that
3508 * the insert is finished with this level.
3512 * Insert nrec/nptr into this level of the tree.
3513 * Note if we fail, nptr will be null.
3515 error = xfs_btree_insrec(pcur, level, &nptr, &rec, key,
3519 xfs_btree_del_cursor(pcur, XFS_BTREE_ERROR);
3523 XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0);
3527 * See if the cursor we just used is trash.
3528 * Can't trash the caller's cursor, but otherwise we should
3529 * if ncur is a new cursor or we're about to be done.
3532 (ncur || xfs_btree_ptr_is_null(cur, &nptr))) {
3533 /* Save the state from the cursor before we trash it */
3534 if (cur->bc_ops->update_cursor)
3535 cur->bc_ops->update_cursor(pcur, cur);
3536 cur->bc_nlevels = pcur->bc_nlevels;
3537 xfs_btree_del_cursor(pcur, XFS_BTREE_NOERROR);
3539 /* If we got a new cursor, switch to it. */
3544 } while (!xfs_btree_ptr_is_null(cur, &nptr));
3546 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3550 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3555 * Try to merge a non-leaf block back into the inode root.
3557 * Note: the killroot names comes from the fact that we're effectively
3558 * killing the old root block. But because we can't just delete the
3559 * inode we have to copy the single block it was pointing to into the
3563 xfs_btree_kill_iroot(
3564 struct xfs_btree_cur *cur)
3566 int whichfork = cur->bc_private.b.whichfork;
3567 struct xfs_inode *ip = cur->bc_private.b.ip;
3568 struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, whichfork);
3569 struct xfs_btree_block *block;
3570 struct xfs_btree_block *cblock;
3571 union xfs_btree_key *kp;
3572 union xfs_btree_key *ckp;
3573 union xfs_btree_ptr *pp;
3574 union xfs_btree_ptr *cpp;
3575 struct xfs_buf *cbp;
3581 union xfs_btree_ptr ptr;
3585 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
3587 ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE);
3588 ASSERT(cur->bc_nlevels > 1);
3591 * Don't deal with the root block needs to be a leaf case.
3592 * We're just going to turn the thing back into extents anyway.
3594 level = cur->bc_nlevels - 1;
3599 * Give up if the root has multiple children.
3601 block = xfs_btree_get_iroot(cur);
3602 if (xfs_btree_get_numrecs(block) != 1)
3605 cblock = xfs_btree_get_block(cur, level - 1, &cbp);
3606 numrecs = xfs_btree_get_numrecs(cblock);
3609 * Only do this if the next level will fit.
3610 * Then the data must be copied up to the inode,
3611 * instead of freeing the root you free the next level.
3613 if (numrecs > cur->bc_ops->get_dmaxrecs(cur, level))
3616 XFS_BTREE_STATS_INC(cur, killroot);
3619 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_LEFTSIB);
3620 ASSERT(xfs_btree_ptr_is_null(cur, &ptr));
3621 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
3622 ASSERT(xfs_btree_ptr_is_null(cur, &ptr));
3625 index = numrecs - cur->bc_ops->get_maxrecs(cur, level);
3627 xfs_iroot_realloc(cur->bc_private.b.ip, index,
3628 cur->bc_private.b.whichfork);
3629 block = ifp->if_broot;
3632 be16_add_cpu(&block->bb_numrecs, index);
3633 ASSERT(block->bb_numrecs == cblock->bb_numrecs);
3635 kp = xfs_btree_key_addr(cur, 1, block);
3636 ckp = xfs_btree_key_addr(cur, 1, cblock);
3637 xfs_btree_copy_keys(cur, kp, ckp, numrecs);
3639 pp = xfs_btree_ptr_addr(cur, 1, block);
3640 cpp = xfs_btree_ptr_addr(cur, 1, cblock);
3642 for (i = 0; i < numrecs; i++) {
3643 error = xfs_btree_check_ptr(cur, cpp, i, level - 1);
3645 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3650 xfs_btree_copy_ptrs(cur, pp, cpp, numrecs);
3652 error = xfs_btree_free_block(cur, cbp);
3654 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3658 cur->bc_bufs[level - 1] = NULL;
3659 be16_add_cpu(&block->bb_level, -1);
3660 xfs_trans_log_inode(cur->bc_tp, ip,
3661 XFS_ILOG_CORE | xfs_ilog_fbroot(cur->bc_private.b.whichfork));
3664 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3669 * Kill the current root node, and replace it with it's only child node.
3672 xfs_btree_kill_root(
3673 struct xfs_btree_cur *cur,
3676 union xfs_btree_ptr *newroot)
3680 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
3681 XFS_BTREE_STATS_INC(cur, killroot);
3684 * Update the root pointer, decreasing the level by 1 and then
3685 * free the old root.
3687 cur->bc_ops->set_root(cur, newroot, -1);
3689 error = xfs_btree_free_block(cur, bp);
3691 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3695 cur->bc_bufs[level] = NULL;
3696 cur->bc_ra[level] = 0;
3699 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3704 xfs_btree_dec_cursor(
3705 struct xfs_btree_cur *cur,
3713 error = xfs_btree_decrement(cur, level, &i);
3718 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3724 * Single level of the btree record deletion routine.
3725 * Delete record pointed to by cur/level.
3726 * Remove the record from its block then rebalance the tree.
3727 * Return 0 for error, 1 for done, 2 to go on to the next level.
3729 STATIC int /* error */
3731 struct xfs_btree_cur *cur, /* btree cursor */
3732 int level, /* level removing record from */
3733 int *stat) /* fail/done/go-on */
3735 struct xfs_btree_block *block; /* btree block */
3736 union xfs_btree_ptr cptr; /* current block ptr */
3737 struct xfs_buf *bp; /* buffer for block */
3738 int error; /* error return value */
3739 int i; /* loop counter */
3740 union xfs_btree_ptr lptr; /* left sibling block ptr */
3741 struct xfs_buf *lbp; /* left buffer pointer */
3742 struct xfs_btree_block *left; /* left btree block */
3743 int lrecs = 0; /* left record count */
3744 int ptr; /* key/record index */
3745 union xfs_btree_ptr rptr; /* right sibling block ptr */
3746 struct xfs_buf *rbp; /* right buffer pointer */
3747 struct xfs_btree_block *right; /* right btree block */
3748 struct xfs_btree_block *rrblock; /* right-right btree block */
3749 struct xfs_buf *rrbp; /* right-right buffer pointer */
3750 int rrecs = 0; /* right record count */
3751 struct xfs_btree_cur *tcur; /* temporary btree cursor */
3752 int numrecs; /* temporary numrec count */
3754 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
3755 XFS_BTREE_TRACE_ARGI(cur, level);
3759 /* Get the index of the entry being deleted, check for nothing there. */
3760 ptr = cur->bc_ptrs[level];
3762 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3767 /* Get the buffer & block containing the record or key/ptr. */
3768 block = xfs_btree_get_block(cur, level, &bp);
3769 numrecs = xfs_btree_get_numrecs(block);
3772 error = xfs_btree_check_block(cur, block, level, bp);
3777 /* Fail if we're off the end of the block. */
3778 if (ptr > numrecs) {
3779 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3784 XFS_BTREE_STATS_INC(cur, delrec);
3785 XFS_BTREE_STATS_ADD(cur, moves, numrecs - ptr);
3787 /* Excise the entries being deleted. */
3789 /* It's a nonleaf. operate on keys and ptrs */
3790 union xfs_btree_key *lkp;
3791 union xfs_btree_ptr *lpp;
3793 lkp = xfs_btree_key_addr(cur, ptr + 1, block);
3794 lpp = xfs_btree_ptr_addr(cur, ptr + 1, block);
3797 for (i = 0; i < numrecs - ptr; i++) {
3798 error = xfs_btree_check_ptr(cur, lpp, i, level);
3804 if (ptr < numrecs) {
3805 xfs_btree_shift_keys(cur, lkp, -1, numrecs - ptr);
3806 xfs_btree_shift_ptrs(cur, lpp, -1, numrecs - ptr);
3807 xfs_btree_log_keys(cur, bp, ptr, numrecs - 1);
3808 xfs_btree_log_ptrs(cur, bp, ptr, numrecs - 1);
3811 /* It's a leaf. operate on records */
3812 if (ptr < numrecs) {
3813 xfs_btree_shift_recs(cur,
3814 xfs_btree_rec_addr(cur, ptr + 1, block),
3816 xfs_btree_log_recs(cur, bp, ptr, numrecs - 1);
3821 * Decrement and log the number of entries in the block.
3823 xfs_btree_set_numrecs(block, --numrecs);
3824 xfs_btree_log_block(cur, bp, XFS_BB_NUMRECS);
3827 * If we are tracking the last record in the tree and
3828 * we are at the far right edge of the tree, update it.
3830 if (xfs_btree_is_lastrec(cur, block, level)) {
3831 cur->bc_ops->update_lastrec(cur, block, NULL,
3832 ptr, LASTREC_DELREC);
3836 * We're at the root level. First, shrink the root block in-memory.
3837 * Try to get rid of the next level down. If we can't then there's
3838 * nothing left to do.
3840 if (level == cur->bc_nlevels - 1) {
3841 if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) {
3842 xfs_iroot_realloc(cur->bc_private.b.ip, -1,
3843 cur->bc_private.b.whichfork);
3845 error = xfs_btree_kill_iroot(cur);
3849 error = xfs_btree_dec_cursor(cur, level, stat);
3857 * If this is the root level, and there's only one entry left,
3858 * and it's NOT the leaf level, then we can get rid of this
3861 if (numrecs == 1 && level > 0) {
3862 union xfs_btree_ptr *pp;
3864 * pp is still set to the first pointer in the block.
3865 * Make it the new root of the btree.
3867 pp = xfs_btree_ptr_addr(cur, 1, block);
3868 error = xfs_btree_kill_root(cur, bp, level, pp);
3871 } else if (level > 0) {
3872 error = xfs_btree_dec_cursor(cur, level, stat);
3881 * If we deleted the leftmost entry in the block, update the
3882 * key values above us in the tree.
3884 if (xfs_btree_needs_key_update(cur, ptr)) {
3885 error = xfs_btree_update_keys(cur, level);
3891 * If the number of records remaining in the block is at least
3892 * the minimum, we're done.
3894 if (numrecs >= cur->bc_ops->get_minrecs(cur, level)) {
3895 error = xfs_btree_dec_cursor(cur, level, stat);
3902 * Otherwise, we have to move some records around to keep the
3903 * tree balanced. Look at the left and right sibling blocks to
3904 * see if we can re-balance by moving only one record.
3906 xfs_btree_get_sibling(cur, block, &rptr, XFS_BB_RIGHTSIB);
3907 xfs_btree_get_sibling(cur, block, &lptr, XFS_BB_LEFTSIB);
3909 if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) {
3911 * One child of root, need to get a chance to copy its contents
3912 * into the root and delete it. Can't go up to next level,
3913 * there's nothing to delete there.
3915 if (xfs_btree_ptr_is_null(cur, &rptr) &&
3916 xfs_btree_ptr_is_null(cur, &lptr) &&
3917 level == cur->bc_nlevels - 2) {
3918 error = xfs_btree_kill_iroot(cur);
3920 error = xfs_btree_dec_cursor(cur, level, stat);
3927 ASSERT(!xfs_btree_ptr_is_null(cur, &rptr) ||
3928 !xfs_btree_ptr_is_null(cur, &lptr));
3931 * Duplicate the cursor so our btree manipulations here won't
3932 * disrupt the next level up.
3934 error = xfs_btree_dup_cursor(cur, &tcur);
3939 * If there's a right sibling, see if it's ok to shift an entry
3942 if (!xfs_btree_ptr_is_null(cur, &rptr)) {
3944 * Move the temp cursor to the last entry in the next block.
3945 * Actually any entry but the first would suffice.
3947 i = xfs_btree_lastrec(tcur, level);
3948 XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0);
3950 error = xfs_btree_increment(tcur, level, &i);
3953 XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0);
3955 i = xfs_btree_lastrec(tcur, level);
3956 XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0);
3958 /* Grab a pointer to the block. */
3959 right = xfs_btree_get_block(tcur, level, &rbp);
3961 error = xfs_btree_check_block(tcur, right, level, rbp);
3965 /* Grab the current block number, for future use. */
3966 xfs_btree_get_sibling(tcur, right, &cptr, XFS_BB_LEFTSIB);
3969 * If right block is full enough so that removing one entry
3970 * won't make it too empty, and left-shifting an entry out
3971 * of right to us works, we're done.
3973 if (xfs_btree_get_numrecs(right) - 1 >=
3974 cur->bc_ops->get_minrecs(tcur, level)) {
3975 error = xfs_btree_lshift(tcur, level, &i);
3979 ASSERT(xfs_btree_get_numrecs(block) >=
3980 cur->bc_ops->get_minrecs(tcur, level));
3982 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
3985 error = xfs_btree_dec_cursor(cur, level, stat);
3993 * Otherwise, grab the number of records in right for
3994 * future reference, and fix up the temp cursor to point
3995 * to our block again (last record).
3997 rrecs = xfs_btree_get_numrecs(right);
3998 if (!xfs_btree_ptr_is_null(cur, &lptr)) {
3999 i = xfs_btree_firstrec(tcur, level);
4000 XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0);
4002 error = xfs_btree_decrement(tcur, level, &i);
4005 XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0);
4010 * If there's a left sibling, see if it's ok to shift an entry
4013 if (!xfs_btree_ptr_is_null(cur, &lptr)) {
4015 * Move the temp cursor to the first entry in the
4018 i = xfs_btree_firstrec(tcur, level);
4019 XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0);
4021 error = xfs_btree_decrement(tcur, level, &i);
4024 i = xfs_btree_firstrec(tcur, level);
4025 XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0);
4027 /* Grab a pointer to the block. */
4028 left = xfs_btree_get_block(tcur, level, &lbp);
4030 error = xfs_btree_check_block(cur, left, level, lbp);
4034 /* Grab the current block number, for future use. */
4035 xfs_btree_get_sibling(tcur, left, &cptr, XFS_BB_RIGHTSIB);
4038 * If left block is full enough so that removing one entry
4039 * won't make it too empty, and right-shifting an entry out
4040 * of left to us works, we're done.
4042 if (xfs_btree_get_numrecs(left) - 1 >=
4043 cur->bc_ops->get_minrecs(tcur, level)) {
4044 error = xfs_btree_rshift(tcur, level, &i);
4048 ASSERT(xfs_btree_get_numrecs(block) >=
4049 cur->bc_ops->get_minrecs(tcur, level));
4050 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
4054 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
4061 * Otherwise, grab the number of records in right for
4064 lrecs = xfs_btree_get_numrecs(left);
4067 /* Delete the temp cursor, we're done with it. */
4068 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
4071 /* If here, we need to do a join to keep the tree balanced. */
4072 ASSERT(!xfs_btree_ptr_is_null(cur, &cptr));
4074 if (!xfs_btree_ptr_is_null(cur, &lptr) &&
4075 lrecs + xfs_btree_get_numrecs(block) <=
4076 cur->bc_ops->get_maxrecs(cur, level)) {
4078 * Set "right" to be the starting block,
4079 * "left" to be the left neighbor.
4084 error = xfs_btree_read_buf_block(cur, &lptr, 0, &left, &lbp);
4089 * If that won't work, see if we can join with the right neighbor block.
4091 } else if (!xfs_btree_ptr_is_null(cur, &rptr) &&
4092 rrecs + xfs_btree_get_numrecs(block) <=
4093 cur->bc_ops->get_maxrecs(cur, level)) {
4095 * Set "left" to be the starting block,
4096 * "right" to be the right neighbor.
4101 error = xfs_btree_read_buf_block(cur, &rptr, 0, &right, &rbp);
4106 * Otherwise, we can't fix the imbalance.
4107 * Just return. This is probably a logic error, but it's not fatal.
4110 error = xfs_btree_dec_cursor(cur, level, stat);
4116 rrecs = xfs_btree_get_numrecs(right);
4117 lrecs = xfs_btree_get_numrecs(left);
4120 * We're now going to join "left" and "right" by moving all the stuff
4121 * in "right" to "left" and deleting "right".
4123 XFS_BTREE_STATS_ADD(cur, moves, rrecs);
4125 /* It's a non-leaf. Move keys and pointers. */
4126 union xfs_btree_key *lkp; /* left btree key */
4127 union xfs_btree_ptr *lpp; /* left address pointer */
4128 union xfs_btree_key *rkp; /* right btree key */
4129 union xfs_btree_ptr *rpp; /* right address pointer */
4131 lkp = xfs_btree_key_addr(cur, lrecs + 1, left);
4132 lpp = xfs_btree_ptr_addr(cur, lrecs + 1, left);
4133 rkp = xfs_btree_key_addr(cur, 1, right);
4134 rpp = xfs_btree_ptr_addr(cur, 1, right);
4136 for (i = 1; i < rrecs; i++) {
4137 error = xfs_btree_check_ptr(cur, rpp, i, level);
4142 xfs_btree_copy_keys(cur, lkp, rkp, rrecs);
4143 xfs_btree_copy_ptrs(cur, lpp, rpp, rrecs);
4145 xfs_btree_log_keys(cur, lbp, lrecs + 1, lrecs + rrecs);
4146 xfs_btree_log_ptrs(cur, lbp, lrecs + 1, lrecs + rrecs);
4148 /* It's a leaf. Move records. */
4149 union xfs_btree_rec *lrp; /* left record pointer */
4150 union xfs_btree_rec *rrp; /* right record pointer */
4152 lrp = xfs_btree_rec_addr(cur, lrecs + 1, left);
4153 rrp = xfs_btree_rec_addr(cur, 1, right);
4155 xfs_btree_copy_recs(cur, lrp, rrp, rrecs);
4156 xfs_btree_log_recs(cur, lbp, lrecs + 1, lrecs + rrecs);
4159 XFS_BTREE_STATS_INC(cur, join);
4162 * Fix up the number of records and right block pointer in the
4163 * surviving block, and log it.
4165 xfs_btree_set_numrecs(left, lrecs + rrecs);
4166 xfs_btree_get_sibling(cur, right, &cptr, XFS_BB_RIGHTSIB),
4167 xfs_btree_set_sibling(cur, left, &cptr, XFS_BB_RIGHTSIB);
4168 xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS | XFS_BB_RIGHTSIB);
4170 /* If there is a right sibling, point it to the remaining block. */
4171 xfs_btree_get_sibling(cur, left, &cptr, XFS_BB_RIGHTSIB);
4172 if (!xfs_btree_ptr_is_null(cur, &cptr)) {
4173 error = xfs_btree_read_buf_block(cur, &cptr, 0, &rrblock, &rrbp);
4176 xfs_btree_set_sibling(cur, rrblock, &lptr, XFS_BB_LEFTSIB);
4177 xfs_btree_log_block(cur, rrbp, XFS_BB_LEFTSIB);
4180 /* Free the deleted block. */
4181 error = xfs_btree_free_block(cur, rbp);
4186 * If we joined with the left neighbor, set the buffer in the
4187 * cursor to the left block, and fix up the index.
4190 cur->bc_bufs[level] = lbp;
4191 cur->bc_ptrs[level] += lrecs;
4192 cur->bc_ra[level] = 0;
4195 * If we joined with the right neighbor and there's a level above
4196 * us, increment the cursor at that level.
4198 else if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) ||
4199 (level + 1 < cur->bc_nlevels)) {
4200 error = xfs_btree_increment(cur, level + 1, &i);
4206 * Readjust the ptr at this level if it's not a leaf, since it's
4207 * still pointing at the deletion point, which makes the cursor
4208 * inconsistent. If this makes the ptr 0, the caller fixes it up.
4209 * We can't use decrement because it would change the next level up.
4212 cur->bc_ptrs[level]--;
4215 * We combined blocks, so we have to update the parent keys if the
4216 * btree supports overlapped intervals. However, bc_ptrs[level + 1]
4217 * points to the old block so that the caller knows which record to
4218 * delete. Therefore, the caller must be savvy enough to call updkeys
4219 * for us if we return stat == 2. The other exit points from this
4220 * function don't require deletions further up the tree, so they can
4221 * call updkeys directly.
4224 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
4225 /* Return value means the next level up has something to do. */
4230 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
4232 xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
4237 * Delete the record pointed to by cur.
4238 * The cursor refers to the place where the record was (could be inserted)
4239 * when the operation returns.
4243 struct xfs_btree_cur *cur,
4244 int *stat) /* success/failure */
4246 int error; /* error return value */
4249 bool joined = false;
4251 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
4254 * Go up the tree, starting at leaf level.
4256 * If 2 is returned then a join was done; go to the next level.
4257 * Otherwise we are done.
4259 for (level = 0, i = 2; i == 2; level++) {
4260 error = xfs_btree_delrec(cur, level, &i);
4268 * If we combined blocks as part of deleting the record, delrec won't
4269 * have updated the parent high keys so we have to do that here.
4271 if (joined && (cur->bc_flags & XFS_BTREE_OVERLAPPING)) {
4272 error = xfs_btree_updkeys_force(cur, 0);
4278 for (level = 1; level < cur->bc_nlevels; level++) {
4279 if (cur->bc_ptrs[level] == 0) {
4280 error = xfs_btree_decrement(cur, level, &i);
4288 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
4292 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
4297 * Get the data from the pointed-to record.
4301 struct xfs_btree_cur *cur, /* btree cursor */
4302 union xfs_btree_rec **recp, /* output: btree record */
4303 int *stat) /* output: success/failure */
4305 struct xfs_btree_block *block; /* btree block */
4306 struct xfs_buf *bp; /* buffer pointer */
4307 int ptr; /* record number */
4309 int error; /* error return value */
4312 ptr = cur->bc_ptrs[0];
4313 block = xfs_btree_get_block(cur, 0, &bp);
4316 error = xfs_btree_check_block(cur, block, 0, bp);
4322 * Off the right end or left end, return failure.
4324 if (ptr > xfs_btree_get_numrecs(block) || ptr <= 0) {
4330 * Point to the record and extract its data.
4332 *recp = xfs_btree_rec_addr(cur, ptr, block);
4337 /* Visit a block in a btree. */
4339 xfs_btree_visit_block(
4340 struct xfs_btree_cur *cur,
4342 xfs_btree_visit_blocks_fn fn,
4345 struct xfs_btree_block *block;
4347 union xfs_btree_ptr rptr;
4350 /* do right sibling readahead */
4351 xfs_btree_readahead(cur, level, XFS_BTCUR_RIGHTRA);
4352 block = xfs_btree_get_block(cur, level, &bp);
4354 /* process the block */
4355 error = fn(cur, level, data);
4359 /* now read rh sibling block for next iteration */
4360 xfs_btree_get_sibling(cur, block, &rptr, XFS_BB_RIGHTSIB);
4361 if (xfs_btree_ptr_is_null(cur, &rptr))
4364 return xfs_btree_lookup_get_block(cur, level, &rptr, &block);
4368 /* Visit every block in a btree. */
4370 xfs_btree_visit_blocks(
4371 struct xfs_btree_cur *cur,
4372 xfs_btree_visit_blocks_fn fn,
4375 union xfs_btree_ptr lptr;
4377 struct xfs_btree_block *block = NULL;
4380 cur->bc_ops->init_ptr_from_cur(cur, &lptr);
4382 /* for each level */
4383 for (level = cur->bc_nlevels - 1; level >= 0; level--) {
4384 /* grab the left hand block */
4385 error = xfs_btree_lookup_get_block(cur, level, &lptr, &block);
4389 /* readahead the left most block for the next level down */
4391 union xfs_btree_ptr *ptr;
4393 ptr = xfs_btree_ptr_addr(cur, 1, block);
4394 xfs_btree_readahead_ptr(cur, ptr, 1);
4396 /* save for the next iteration of the loop */
4400 /* for each buffer in the level */
4402 error = xfs_btree_visit_block(cur, level, fn, data);
4405 if (error != -ENOENT)
4413 * Change the owner of a btree.
4415 * The mechanism we use here is ordered buffer logging. Because we don't know
4416 * how many buffers were are going to need to modify, we don't really want to
4417 * have to make transaction reservations for the worst case of every buffer in a
4418 * full size btree as that may be more space that we can fit in the log....
4420 * We do the btree walk in the most optimal manner possible - we have sibling
4421 * pointers so we can just walk all the blocks on each level from left to right
4422 * in a single pass, and then move to the next level and do the same. We can
4423 * also do readahead on the sibling pointers to get IO moving more quickly,
4424 * though for slow disks this is unlikely to make much difference to performance
4425 * as the amount of CPU work we have to do before moving to the next block is
4428 * For each btree block that we load, modify the owner appropriately, set the
4429 * buffer as an ordered buffer and log it appropriately. We need to ensure that
4430 * we mark the region we change dirty so that if the buffer is relogged in
4431 * a subsequent transaction the changes we make here as an ordered buffer are
4432 * correctly relogged in that transaction. If we are in recovery context, then
4433 * just queue the modified buffer as delayed write buffer so the transaction
4434 * recovery completion writes the changes to disk.
4436 struct xfs_btree_block_change_owner_info {
4437 __uint64_t new_owner;
4438 struct list_head *buffer_list;
4442 xfs_btree_block_change_owner(
4443 struct xfs_btree_cur *cur,
4447 struct xfs_btree_block_change_owner_info *bbcoi = data;
4448 struct xfs_btree_block *block;
4451 /* modify the owner */
4452 block = xfs_btree_get_block(cur, level, &bp);
4453 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
4454 block->bb_u.l.bb_owner = cpu_to_be64(bbcoi->new_owner);
4456 block->bb_u.s.bb_owner = cpu_to_be32(bbcoi->new_owner);
4459 * If the block is a root block hosted in an inode, we might not have a
4460 * buffer pointer here and we shouldn't attempt to log the change as the
4461 * information is already held in the inode and discarded when the root
4462 * block is formatted into the on-disk inode fork. We still change it,
4463 * though, so everything is consistent in memory.
4467 xfs_trans_ordered_buf(cur->bc_tp, bp);
4468 xfs_btree_log_block(cur, bp, XFS_BB_OWNER);
4470 xfs_buf_delwri_queue(bp, bbcoi->buffer_list);
4473 ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE);
4474 ASSERT(level == cur->bc_nlevels - 1);
4481 xfs_btree_change_owner(
4482 struct xfs_btree_cur *cur,
4483 __uint64_t new_owner,
4484 struct list_head *buffer_list)
4486 struct xfs_btree_block_change_owner_info bbcoi;
4488 bbcoi.new_owner = new_owner;
4489 bbcoi.buffer_list = buffer_list;
4491 return xfs_btree_visit_blocks(cur, xfs_btree_block_change_owner,
4496 * xfs_btree_sblock_v5hdr_verify() -- verify the v5 fields of a short-format
4499 * @bp: buffer containing the btree block
4500 * @max_recs: pointer to the m_*_mxr max records field in the xfs mount
4501 * @pag_max_level: pointer to the per-ag max level field
4504 xfs_btree_sblock_v5hdr_verify(
4507 struct xfs_mount *mp = bp->b_target->bt_mount;
4508 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
4509 struct xfs_perag *pag = bp->b_pag;
4511 if (!xfs_sb_version_hascrc(&mp->m_sb))
4513 if (!uuid_equal(&block->bb_u.s.bb_uuid, &mp->m_sb.sb_meta_uuid))
4515 if (block->bb_u.s.bb_blkno != cpu_to_be64(bp->b_bn))
4517 if (pag && be32_to_cpu(block->bb_u.s.bb_owner) != pag->pag_agno)
4523 * xfs_btree_sblock_verify() -- verify a short-format btree block
4525 * @bp: buffer containing the btree block
4526 * @max_recs: maximum records allowed in this btree node
4529 xfs_btree_sblock_verify(
4531 unsigned int max_recs)
4533 struct xfs_mount *mp = bp->b_target->bt_mount;
4534 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
4536 /* numrecs verification */
4537 if (be16_to_cpu(block->bb_numrecs) > max_recs)
4540 /* sibling pointer verification */
4541 if (!block->bb_u.s.bb_leftsib ||
4542 (be32_to_cpu(block->bb_u.s.bb_leftsib) >= mp->m_sb.sb_agblocks &&
4543 block->bb_u.s.bb_leftsib != cpu_to_be32(NULLAGBLOCK)))
4545 if (!block->bb_u.s.bb_rightsib ||
4546 (be32_to_cpu(block->bb_u.s.bb_rightsib) >= mp->m_sb.sb_agblocks &&
4547 block->bb_u.s.bb_rightsib != cpu_to_be32(NULLAGBLOCK)))
4554 * Calculate the number of btree levels needed to store a given number of
4555 * records in a short-format btree.
4558 xfs_btree_compute_maxlevels(
4559 struct xfs_mount *mp,
4564 unsigned long maxblocks;
4566 maxblocks = (len + limits[0] - 1) / limits[0];
4567 for (level = 1; maxblocks > 1; level++)
4568 maxblocks = (maxblocks + limits[1] - 1) / limits[1];
4573 * Query a regular btree for all records overlapping a given interval.
4574 * Start with a LE lookup of the key of low_rec and return all records
4575 * until we find a record with a key greater than the key of high_rec.
4578 xfs_btree_simple_query_range(
4579 struct xfs_btree_cur *cur,
4580 union xfs_btree_key *low_key,
4581 union xfs_btree_key *high_key,
4582 xfs_btree_query_range_fn fn,
4585 union xfs_btree_rec *recp;
4586 union xfs_btree_key rec_key;
4589 bool firstrec = true;
4592 ASSERT(cur->bc_ops->init_high_key_from_rec);
4593 ASSERT(cur->bc_ops->diff_two_keys);
4596 * Find the leftmost record. The btree cursor must be set
4597 * to the low record used to generate low_key.
4600 error = xfs_btree_lookup(cur, XFS_LOOKUP_LE, &stat);
4604 /* Nothing? See if there's anything to the right. */
4606 error = xfs_btree_increment(cur, 0, &stat);
4612 /* Find the record. */
4613 error = xfs_btree_get_rec(cur, &recp, &stat);
4617 /* Skip if high_key(rec) < low_key. */
4619 cur->bc_ops->init_high_key_from_rec(&rec_key, recp);
4621 diff = cur->bc_ops->diff_two_keys(cur, low_key,
4627 /* Stop if high_key < low_key(rec). */
4628 cur->bc_ops->init_key_from_rec(&rec_key, recp);
4629 diff = cur->bc_ops->diff_two_keys(cur, &rec_key, high_key);
4634 error = fn(cur, recp, priv);
4635 if (error < 0 || error == XFS_BTREE_QUERY_RANGE_ABORT)
4639 /* Move on to the next record. */
4640 error = xfs_btree_increment(cur, 0, &stat);
4650 * Query an overlapped interval btree for all records overlapping a given
4651 * interval. This function roughly follows the algorithm given in
4652 * "Interval Trees" of _Introduction to Algorithms_, which is section
4653 * 14.3 in the 2nd and 3rd editions.
4655 * First, generate keys for the low and high records passed in.
4657 * For any leaf node, generate the high and low keys for the record.
4658 * If the record keys overlap with the query low/high keys, pass the
4659 * record to the function iterator.
4661 * For any internal node, compare the low and high keys of each
4662 * pointer against the query low/high keys. If there's an overlap,
4663 * follow the pointer.
4665 * As an optimization, we stop scanning a block when we find a low key
4666 * that is greater than the query's high key.
4669 xfs_btree_overlapped_query_range(
4670 struct xfs_btree_cur *cur,
4671 union xfs_btree_key *low_key,
4672 union xfs_btree_key *high_key,
4673 xfs_btree_query_range_fn fn,
4676 union xfs_btree_ptr ptr;
4677 union xfs_btree_ptr *pp;
4678 union xfs_btree_key rec_key;
4679 union xfs_btree_key rec_hkey;
4680 union xfs_btree_key *lkp;
4681 union xfs_btree_key *hkp;
4682 union xfs_btree_rec *recp;
4683 struct xfs_btree_block *block;
4691 /* Load the root of the btree. */
4692 level = cur->bc_nlevels - 1;
4693 cur->bc_ops->init_ptr_from_cur(cur, &ptr);
4694 error = xfs_btree_lookup_get_block(cur, level, &ptr, &block);
4697 xfs_btree_get_block(cur, level, &bp);
4698 trace_xfs_btree_overlapped_query_range(cur, level, bp);
4700 error = xfs_btree_check_block(cur, block, level, bp);
4704 cur->bc_ptrs[level] = 1;
4706 while (level < cur->bc_nlevels) {
4707 block = xfs_btree_get_block(cur, level, &bp);
4709 /* End of node, pop back towards the root. */
4710 if (cur->bc_ptrs[level] > be16_to_cpu(block->bb_numrecs)) {
4712 if (level < cur->bc_nlevels - 1)
4713 cur->bc_ptrs[level + 1]++;
4719 /* Handle a leaf node. */
4720 recp = xfs_btree_rec_addr(cur, cur->bc_ptrs[0], block);
4722 cur->bc_ops->init_high_key_from_rec(&rec_hkey, recp);
4723 ldiff = cur->bc_ops->diff_two_keys(cur, &rec_hkey,
4726 cur->bc_ops->init_key_from_rec(&rec_key, recp);
4727 hdiff = cur->bc_ops->diff_two_keys(cur, high_key,
4731 * If (record's high key >= query's low key) and
4732 * (query's high key >= record's low key), then
4733 * this record overlaps the query range; callback.
4735 if (ldiff >= 0 && hdiff >= 0) {
4736 error = fn(cur, recp, priv);
4738 error == XFS_BTREE_QUERY_RANGE_ABORT)
4740 } else if (hdiff < 0) {
4741 /* Record is larger than high key; pop. */
4744 cur->bc_ptrs[level]++;
4748 /* Handle an internal node. */
4749 lkp = xfs_btree_key_addr(cur, cur->bc_ptrs[level], block);
4750 hkp = xfs_btree_high_key_addr(cur, cur->bc_ptrs[level], block);
4751 pp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[level], block);
4753 ldiff = cur->bc_ops->diff_two_keys(cur, hkp, low_key);
4754 hdiff = cur->bc_ops->diff_two_keys(cur, high_key, lkp);
4757 * If (pointer's high key >= query's low key) and
4758 * (query's high key >= pointer's low key), then
4759 * this record overlaps the query range; follow pointer.
4761 if (ldiff >= 0 && hdiff >= 0) {
4763 error = xfs_btree_lookup_get_block(cur, level, pp,
4767 xfs_btree_get_block(cur, level, &bp);
4768 trace_xfs_btree_overlapped_query_range(cur, level, bp);
4770 error = xfs_btree_check_block(cur, block, level, bp);
4774 cur->bc_ptrs[level] = 1;
4776 } else if (hdiff < 0) {
4777 /* The low key is larger than the upper range; pop. */
4780 cur->bc_ptrs[level]++;
4785 * If we don't end this function with the cursor pointing at a record
4786 * block, a subsequent non-error cursor deletion will not release
4787 * node-level buffers, causing a buffer leak. This is quite possible
4788 * with a zero-results range query, so release the buffers if we
4789 * failed to return any results.
4791 if (cur->bc_bufs[0] == NULL) {
4792 for (i = 0; i < cur->bc_nlevels; i++) {
4793 if (cur->bc_bufs[i]) {
4794 xfs_trans_brelse(cur->bc_tp, cur->bc_bufs[i]);
4795 cur->bc_bufs[i] = NULL;
4796 cur->bc_ptrs[i] = 0;
4806 * Query a btree for all records overlapping a given interval of keys. The
4807 * supplied function will be called with each record found; return one of the
4808 * XFS_BTREE_QUERY_RANGE_{CONTINUE,ABORT} values or the usual negative error
4809 * code. This function returns XFS_BTREE_QUERY_RANGE_ABORT, zero, or a
4810 * negative error code.
4813 xfs_btree_query_range(
4814 struct xfs_btree_cur *cur,
4815 union xfs_btree_irec *low_rec,
4816 union xfs_btree_irec *high_rec,
4817 xfs_btree_query_range_fn fn,
4820 union xfs_btree_rec rec;
4821 union xfs_btree_key low_key;
4822 union xfs_btree_key high_key;
4824 /* Find the keys of both ends of the interval. */
4825 cur->bc_rec = *high_rec;
4826 cur->bc_ops->init_rec_from_cur(cur, &rec);
4827 cur->bc_ops->init_key_from_rec(&high_key, &rec);
4829 cur->bc_rec = *low_rec;
4830 cur->bc_ops->init_rec_from_cur(cur, &rec);
4831 cur->bc_ops->init_key_from_rec(&low_key, &rec);
4833 /* Enforce low key < high key. */
4834 if (cur->bc_ops->diff_two_keys(cur, &low_key, &high_key) > 0)
4837 if (!(cur->bc_flags & XFS_BTREE_OVERLAPPING))
4838 return xfs_btree_simple_query_range(cur, &low_key,
4839 &high_key, fn, priv);
4840 return xfs_btree_overlapped_query_range(cur, &low_key, &high_key,
4845 * Calculate the number of blocks needed to store a given number of records
4846 * in a short-format (per-AG metadata) btree.
4849 xfs_btree_calc_size(
4850 struct xfs_mount *mp,
4852 unsigned long long len)
4858 maxrecs = limits[0];
4859 for (level = 0, rval = 0; len > 1; level++) {
4861 do_div(len, maxrecs);
4862 maxrecs = limits[1];
4869 xfs_btree_count_blocks_helper(
4870 struct xfs_btree_cur *cur,
4874 xfs_extlen_t *blocks = data;
4880 /* Count the blocks in a btree and return the result in *blocks. */
4882 xfs_btree_count_blocks(
4883 struct xfs_btree_cur *cur,
4884 xfs_extlen_t *blocks)
4887 return xfs_btree_visit_blocks(cur, xfs_btree_count_blocks_helper,