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,
53 #define xfs_btree_magic(cur) \
54 xfs_magics[!!((cur)->bc_flags & XFS_BTREE_CRC_BLOCKS)][cur->bc_btnum]
56 STATIC int /* error (0 or EFSCORRUPTED) */
57 xfs_btree_check_lblock(
58 struct xfs_btree_cur *cur, /* btree cursor */
59 struct xfs_btree_block *block, /* btree long form block pointer */
60 int level, /* level of the btree block */
61 struct xfs_buf *bp) /* buffer for block, if any */
63 int lblock_ok = 1; /* block passes checks */
64 struct xfs_mount *mp; /* file system mount point */
68 if (xfs_sb_version_hascrc(&mp->m_sb)) {
69 lblock_ok = lblock_ok &&
70 uuid_equal(&block->bb_u.l.bb_uuid,
71 &mp->m_sb.sb_meta_uuid) &&
72 block->bb_u.l.bb_blkno == cpu_to_be64(
73 bp ? bp->b_bn : XFS_BUF_DADDR_NULL);
76 lblock_ok = lblock_ok &&
77 be32_to_cpu(block->bb_magic) == xfs_btree_magic(cur) &&
78 be16_to_cpu(block->bb_level) == level &&
79 be16_to_cpu(block->bb_numrecs) <=
80 cur->bc_ops->get_maxrecs(cur, level) &&
81 block->bb_u.l.bb_leftsib &&
82 (block->bb_u.l.bb_leftsib == cpu_to_be64(NULLFSBLOCK) ||
83 XFS_FSB_SANITY_CHECK(mp,
84 be64_to_cpu(block->bb_u.l.bb_leftsib))) &&
85 block->bb_u.l.bb_rightsib &&
86 (block->bb_u.l.bb_rightsib == cpu_to_be64(NULLFSBLOCK) ||
87 XFS_FSB_SANITY_CHECK(mp,
88 be64_to_cpu(block->bb_u.l.bb_rightsib)));
90 if (unlikely(XFS_TEST_ERROR(!lblock_ok, mp,
91 XFS_ERRTAG_BTREE_CHECK_LBLOCK,
92 XFS_RANDOM_BTREE_CHECK_LBLOCK))) {
94 trace_xfs_btree_corrupt(bp, _RET_IP_);
95 XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, mp);
101 STATIC int /* error (0 or EFSCORRUPTED) */
102 xfs_btree_check_sblock(
103 struct xfs_btree_cur *cur, /* btree cursor */
104 struct xfs_btree_block *block, /* btree short form block pointer */
105 int level, /* level of the btree block */
106 struct xfs_buf *bp) /* buffer containing block */
108 struct xfs_mount *mp; /* file system mount point */
109 struct xfs_buf *agbp; /* buffer for ag. freespace struct */
110 struct xfs_agf *agf; /* ag. freespace structure */
111 xfs_agblock_t agflen; /* native ag. freespace length */
112 int sblock_ok = 1; /* block passes checks */
115 agbp = cur->bc_private.a.agbp;
116 agf = XFS_BUF_TO_AGF(agbp);
117 agflen = be32_to_cpu(agf->agf_length);
119 if (xfs_sb_version_hascrc(&mp->m_sb)) {
120 sblock_ok = sblock_ok &&
121 uuid_equal(&block->bb_u.s.bb_uuid,
122 &mp->m_sb.sb_meta_uuid) &&
123 block->bb_u.s.bb_blkno == cpu_to_be64(
124 bp ? bp->b_bn : XFS_BUF_DADDR_NULL);
127 sblock_ok = sblock_ok &&
128 be32_to_cpu(block->bb_magic) == xfs_btree_magic(cur) &&
129 be16_to_cpu(block->bb_level) == level &&
130 be16_to_cpu(block->bb_numrecs) <=
131 cur->bc_ops->get_maxrecs(cur, level) &&
132 (block->bb_u.s.bb_leftsib == cpu_to_be32(NULLAGBLOCK) ||
133 be32_to_cpu(block->bb_u.s.bb_leftsib) < agflen) &&
134 block->bb_u.s.bb_leftsib &&
135 (block->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK) ||
136 be32_to_cpu(block->bb_u.s.bb_rightsib) < agflen) &&
137 block->bb_u.s.bb_rightsib;
139 if (unlikely(XFS_TEST_ERROR(!sblock_ok, mp,
140 XFS_ERRTAG_BTREE_CHECK_SBLOCK,
141 XFS_RANDOM_BTREE_CHECK_SBLOCK))) {
143 trace_xfs_btree_corrupt(bp, _RET_IP_);
144 XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, mp);
145 return -EFSCORRUPTED;
151 * Debug routine: check that block header is ok.
154 xfs_btree_check_block(
155 struct xfs_btree_cur *cur, /* btree cursor */
156 struct xfs_btree_block *block, /* generic btree block pointer */
157 int level, /* level of the btree block */
158 struct xfs_buf *bp) /* buffer containing block, if any */
160 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
161 return xfs_btree_check_lblock(cur, block, level, bp);
163 return xfs_btree_check_sblock(cur, block, level, bp);
167 * Check that (long) pointer is ok.
169 int /* error (0 or EFSCORRUPTED) */
170 xfs_btree_check_lptr(
171 struct xfs_btree_cur *cur, /* btree cursor */
172 xfs_fsblock_t bno, /* btree block disk address */
173 int level) /* btree block level */
175 XFS_WANT_CORRUPTED_RETURN(cur->bc_mp,
177 bno != NULLFSBLOCK &&
178 XFS_FSB_SANITY_CHECK(cur->bc_mp, bno));
184 * Check that (short) pointer is ok.
186 STATIC int /* error (0 or EFSCORRUPTED) */
187 xfs_btree_check_sptr(
188 struct xfs_btree_cur *cur, /* btree cursor */
189 xfs_agblock_t bno, /* btree block disk address */
190 int level) /* btree block level */
192 xfs_agblock_t agblocks = cur->bc_mp->m_sb.sb_agblocks;
194 XFS_WANT_CORRUPTED_RETURN(cur->bc_mp,
196 bno != NULLAGBLOCK &&
203 * Check that block ptr is ok.
205 STATIC int /* error (0 or EFSCORRUPTED) */
207 struct xfs_btree_cur *cur, /* btree cursor */
208 union xfs_btree_ptr *ptr, /* btree block disk address */
209 int index, /* offset from ptr to check */
210 int level) /* btree block level */
212 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
213 return xfs_btree_check_lptr(cur,
214 be64_to_cpu((&ptr->l)[index]), level);
216 return xfs_btree_check_sptr(cur,
217 be32_to_cpu((&ptr->s)[index]), level);
223 * Calculate CRC on the whole btree block and stuff it into the
224 * long-form btree header.
226 * Prior to calculting the CRC, pull the LSN out of the buffer log item and put
227 * it into the buffer so recovery knows what the last modification was that made
231 xfs_btree_lblock_calc_crc(
234 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
235 struct xfs_buf_log_item *bip = bp->b_fspriv;
237 if (!xfs_sb_version_hascrc(&bp->b_target->bt_mount->m_sb))
240 block->bb_u.l.bb_lsn = cpu_to_be64(bip->bli_item.li_lsn);
241 xfs_buf_update_cksum(bp, XFS_BTREE_LBLOCK_CRC_OFF);
245 xfs_btree_lblock_verify_crc(
248 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
249 struct xfs_mount *mp = bp->b_target->bt_mount;
251 if (xfs_sb_version_hascrc(&mp->m_sb)) {
252 if (!xfs_log_check_lsn(mp, be64_to_cpu(block->bb_u.l.bb_lsn)))
254 return xfs_buf_verify_cksum(bp, XFS_BTREE_LBLOCK_CRC_OFF);
261 * Calculate CRC on the whole btree block and stuff it into the
262 * short-form btree header.
264 * Prior to calculting the CRC, pull the LSN out of the buffer log item and put
265 * it into the buffer so recovery knows what the last modification was that made
269 xfs_btree_sblock_calc_crc(
272 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
273 struct xfs_buf_log_item *bip = bp->b_fspriv;
275 if (!xfs_sb_version_hascrc(&bp->b_target->bt_mount->m_sb))
278 block->bb_u.s.bb_lsn = cpu_to_be64(bip->bli_item.li_lsn);
279 xfs_buf_update_cksum(bp, XFS_BTREE_SBLOCK_CRC_OFF);
283 xfs_btree_sblock_verify_crc(
286 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
287 struct xfs_mount *mp = bp->b_target->bt_mount;
289 if (xfs_sb_version_hascrc(&mp->m_sb)) {
290 if (!xfs_log_check_lsn(mp, be64_to_cpu(block->bb_u.s.bb_lsn)))
292 return xfs_buf_verify_cksum(bp, XFS_BTREE_SBLOCK_CRC_OFF);
299 xfs_btree_free_block(
300 struct xfs_btree_cur *cur,
305 error = cur->bc_ops->free_block(cur, bp);
307 xfs_trans_binval(cur->bc_tp, bp);
308 XFS_BTREE_STATS_INC(cur, free);
314 * Delete the btree cursor.
317 xfs_btree_del_cursor(
318 xfs_btree_cur_t *cur, /* btree cursor */
319 int error) /* del because of error */
321 int i; /* btree level */
324 * Clear the buffer pointers, and release the buffers.
325 * If we're doing this in the face of an error, we
326 * need to make sure to inspect all of the entries
327 * in the bc_bufs array for buffers to be unlocked.
328 * This is because some of the btree code works from
329 * level n down to 0, and if we get an error along
330 * the way we won't have initialized all the entries
333 for (i = 0; i < cur->bc_nlevels; i++) {
335 xfs_trans_brelse(cur->bc_tp, cur->bc_bufs[i]);
340 * Can't free a bmap cursor without having dealt with the
341 * allocated indirect blocks' accounting.
343 ASSERT(cur->bc_btnum != XFS_BTNUM_BMAP ||
344 cur->bc_private.b.allocated == 0);
348 kmem_zone_free(xfs_btree_cur_zone, cur);
352 * Duplicate the btree cursor.
353 * Allocate a new one, copy the record, re-get the buffers.
356 xfs_btree_dup_cursor(
357 xfs_btree_cur_t *cur, /* input cursor */
358 xfs_btree_cur_t **ncur) /* output cursor */
360 xfs_buf_t *bp; /* btree block's buffer pointer */
361 int error; /* error return value */
362 int i; /* level number of btree block */
363 xfs_mount_t *mp; /* mount structure for filesystem */
364 xfs_btree_cur_t *new; /* new cursor value */
365 xfs_trans_t *tp; /* transaction pointer, can be NULL */
371 * Allocate a new cursor like the old one.
373 new = cur->bc_ops->dup_cursor(cur);
376 * Copy the record currently in the cursor.
378 new->bc_rec = cur->bc_rec;
381 * For each level current, re-get the buffer and copy the ptr value.
383 for (i = 0; i < new->bc_nlevels; i++) {
384 new->bc_ptrs[i] = cur->bc_ptrs[i];
385 new->bc_ra[i] = cur->bc_ra[i];
386 bp = cur->bc_bufs[i];
388 error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
389 XFS_BUF_ADDR(bp), mp->m_bsize,
391 cur->bc_ops->buf_ops);
393 xfs_btree_del_cursor(new, error);
398 new->bc_bufs[i] = bp;
405 * XFS btree block layout and addressing:
407 * There are two types of blocks in the btree: leaf and non-leaf blocks.
409 * The leaf record start with a header then followed by records containing
410 * the values. A non-leaf block also starts with the same header, and
411 * then first contains lookup keys followed by an equal number of pointers
412 * to the btree blocks at the previous level.
414 * +--------+-------+-------+-------+-------+-------+-------+
415 * Leaf: | header | rec 1 | rec 2 | rec 3 | rec 4 | rec 5 | rec N |
416 * +--------+-------+-------+-------+-------+-------+-------+
418 * +--------+-------+-------+-------+-------+-------+-------+
419 * Non-Leaf: | header | key 1 | key 2 | key N | ptr 1 | ptr 2 | ptr N |
420 * +--------+-------+-------+-------+-------+-------+-------+
422 * The header is called struct xfs_btree_block for reasons better left unknown
423 * and comes in different versions for short (32bit) and long (64bit) block
424 * pointers. The record and key structures are defined by the btree instances
425 * and opaque to the btree core. The block pointers are simple disk endian
426 * integers, available in a short (32bit) and long (64bit) variant.
428 * The helpers below calculate the offset of a given record, key or pointer
429 * into a btree block (xfs_btree_*_offset) or return a pointer to the given
430 * record, key or pointer (xfs_btree_*_addr). Note that all addressing
431 * inside the btree block is done using indices starting at one, not zero!
433 * If XFS_BTREE_OVERLAPPING is set, then this btree supports keys containing
434 * overlapping intervals. In such a tree, records are still sorted lowest to
435 * highest and indexed by the smallest key value that refers to the record.
436 * However, nodes are different: each pointer has two associated keys -- one
437 * indexing the lowest key available in the block(s) below (the same behavior
438 * as the key in a regular btree) and another indexing the highest key
439 * available in the block(s) below. Because records are /not/ sorted by the
440 * highest key, all leaf block updates require us to compute the highest key
441 * that matches any record in the leaf and to recursively update the high keys
442 * in the nodes going further up in the tree, if necessary. Nodes look like
445 * +--------+-----+-----+-----+-----+-----+-------+-------+-----+
446 * Non-Leaf: | header | lo1 | hi1 | lo2 | hi2 | ... | ptr 1 | ptr 2 | ... |
447 * +--------+-----+-----+-----+-----+-----+-------+-------+-----+
449 * To perform an interval query on an overlapped tree, perform the usual
450 * depth-first search and use the low and high keys to decide if we can skip
451 * that particular node. If a leaf node is reached, return the records that
452 * intersect the interval. Note that an interval query may return numerous
453 * entries. For a non-overlapped tree, simply search for the record associated
454 * with the lowest key and iterate forward until a non-matching record is
455 * found. Section 14.3 ("Interval Trees") of _Introduction to Algorithms_ by
456 * Cormen, Leiserson, Rivest, and Stein (2nd or 3rd ed. only) discuss this in
459 * Why do we care about overlapping intervals? Let's say you have a bunch of
460 * reverse mapping records on a reflink filesystem:
462 * 1: +- file A startblock B offset C length D -----------+
463 * 2: +- file E startblock F offset G length H --------------+
464 * 3: +- file I startblock F offset J length K --+
465 * 4: +- file L... --+
467 * Now say we want to map block (B+D) into file A at offset (C+D). Ideally,
468 * we'd simply increment the length of record 1. But how do we find the record
469 * that ends at (B+D-1) (i.e. record 1)? A LE lookup of (B+D-1) would return
470 * record 3 because the keys are ordered first by startblock. An interval
471 * query would return records 1 and 2 because they both overlap (B+D-1), and
472 * from that we can pick out record 1 as the appropriate left neighbor.
474 * In the non-overlapped case you can do a LE lookup and decrement the cursor
475 * because a record's interval must end before the next record.
479 * Return size of the btree block header for this btree instance.
481 static inline size_t xfs_btree_block_len(struct xfs_btree_cur *cur)
483 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
484 if (cur->bc_flags & XFS_BTREE_CRC_BLOCKS)
485 return XFS_BTREE_LBLOCK_CRC_LEN;
486 return XFS_BTREE_LBLOCK_LEN;
488 if (cur->bc_flags & XFS_BTREE_CRC_BLOCKS)
489 return XFS_BTREE_SBLOCK_CRC_LEN;
490 return XFS_BTREE_SBLOCK_LEN;
494 * Return size of btree block pointers for this btree instance.
496 static inline size_t xfs_btree_ptr_len(struct xfs_btree_cur *cur)
498 return (cur->bc_flags & XFS_BTREE_LONG_PTRS) ?
499 sizeof(__be64) : sizeof(__be32);
503 * Calculate offset of the n-th record in a btree block.
506 xfs_btree_rec_offset(
507 struct xfs_btree_cur *cur,
510 return xfs_btree_block_len(cur) +
511 (n - 1) * cur->bc_ops->rec_len;
515 * Calculate offset of the n-th key in a btree block.
518 xfs_btree_key_offset(
519 struct xfs_btree_cur *cur,
522 return xfs_btree_block_len(cur) +
523 (n - 1) * cur->bc_ops->key_len;
527 * Calculate offset of the n-th high key in a btree block.
530 xfs_btree_high_key_offset(
531 struct xfs_btree_cur *cur,
534 return xfs_btree_block_len(cur) +
535 (n - 1) * cur->bc_ops->key_len + (cur->bc_ops->key_len / 2);
539 * Calculate offset of the n-th block pointer in a btree block.
542 xfs_btree_ptr_offset(
543 struct xfs_btree_cur *cur,
547 return xfs_btree_block_len(cur) +
548 cur->bc_ops->get_maxrecs(cur, level) * cur->bc_ops->key_len +
549 (n - 1) * xfs_btree_ptr_len(cur);
553 * Return a pointer to the n-th record in the btree block.
555 STATIC union xfs_btree_rec *
557 struct xfs_btree_cur *cur,
559 struct xfs_btree_block *block)
561 return (union xfs_btree_rec *)
562 ((char *)block + xfs_btree_rec_offset(cur, n));
566 * Return a pointer to the n-th key in the btree block.
568 STATIC union xfs_btree_key *
570 struct xfs_btree_cur *cur,
572 struct xfs_btree_block *block)
574 return (union xfs_btree_key *)
575 ((char *)block + xfs_btree_key_offset(cur, n));
579 * Return a pointer to the n-th high key in the btree block.
581 STATIC union xfs_btree_key *
582 xfs_btree_high_key_addr(
583 struct xfs_btree_cur *cur,
585 struct xfs_btree_block *block)
587 return (union xfs_btree_key *)
588 ((char *)block + xfs_btree_high_key_offset(cur, n));
592 * Return a pointer to the n-th block pointer in the btree block.
594 STATIC union xfs_btree_ptr *
596 struct xfs_btree_cur *cur,
598 struct xfs_btree_block *block)
600 int level = xfs_btree_get_level(block);
602 ASSERT(block->bb_level != 0);
604 return (union xfs_btree_ptr *)
605 ((char *)block + xfs_btree_ptr_offset(cur, n, level));
609 * Get the root block which is stored in the inode.
611 * For now this btree implementation assumes the btree root is always
612 * stored in the if_broot field of an inode fork.
614 STATIC struct xfs_btree_block *
616 struct xfs_btree_cur *cur)
618 struct xfs_ifork *ifp;
620 ifp = XFS_IFORK_PTR(cur->bc_private.b.ip, cur->bc_private.b.whichfork);
621 return (struct xfs_btree_block *)ifp->if_broot;
625 * Retrieve the block pointer from the cursor at the given level.
626 * This may be an inode btree root or from a buffer.
628 STATIC struct xfs_btree_block * /* generic btree block pointer */
630 struct xfs_btree_cur *cur, /* btree cursor */
631 int level, /* level in btree */
632 struct xfs_buf **bpp) /* buffer containing the block */
634 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
635 (level == cur->bc_nlevels - 1)) {
637 return xfs_btree_get_iroot(cur);
640 *bpp = cur->bc_bufs[level];
641 return XFS_BUF_TO_BLOCK(*bpp);
645 * Get a buffer for the block, return it with no data read.
646 * Long-form addressing.
648 xfs_buf_t * /* buffer for fsbno */
650 xfs_mount_t *mp, /* file system mount point */
651 xfs_trans_t *tp, /* transaction pointer */
652 xfs_fsblock_t fsbno, /* file system block number */
653 uint lock) /* lock flags for get_buf */
655 xfs_daddr_t d; /* real disk block address */
657 ASSERT(fsbno != NULLFSBLOCK);
658 d = XFS_FSB_TO_DADDR(mp, fsbno);
659 return xfs_trans_get_buf(tp, mp->m_ddev_targp, d, mp->m_bsize, lock);
663 * Get a buffer for the block, return it with no data read.
664 * Short-form addressing.
666 xfs_buf_t * /* buffer for agno/agbno */
668 xfs_mount_t *mp, /* file system mount point */
669 xfs_trans_t *tp, /* transaction pointer */
670 xfs_agnumber_t agno, /* allocation group number */
671 xfs_agblock_t agbno, /* allocation group block number */
672 uint lock) /* lock flags for get_buf */
674 xfs_daddr_t d; /* real disk block address */
676 ASSERT(agno != NULLAGNUMBER);
677 ASSERT(agbno != NULLAGBLOCK);
678 d = XFS_AGB_TO_DADDR(mp, agno, agbno);
679 return xfs_trans_get_buf(tp, mp->m_ddev_targp, d, mp->m_bsize, lock);
683 * Check for the cursor referring to the last block at the given level.
685 int /* 1=is last block, 0=not last block */
686 xfs_btree_islastblock(
687 xfs_btree_cur_t *cur, /* btree cursor */
688 int level) /* level to check */
690 struct xfs_btree_block *block; /* generic btree block pointer */
691 xfs_buf_t *bp; /* buffer containing block */
693 block = xfs_btree_get_block(cur, level, &bp);
694 xfs_btree_check_block(cur, block, level, bp);
695 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
696 return block->bb_u.l.bb_rightsib == cpu_to_be64(NULLFSBLOCK);
698 return block->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK);
702 * Change the cursor to point to the first record at the given level.
703 * Other levels are unaffected.
705 STATIC int /* success=1, failure=0 */
707 xfs_btree_cur_t *cur, /* btree cursor */
708 int level) /* level to change */
710 struct xfs_btree_block *block; /* generic btree block pointer */
711 xfs_buf_t *bp; /* buffer containing block */
714 * Get the block pointer for this level.
716 block = xfs_btree_get_block(cur, level, &bp);
717 xfs_btree_check_block(cur, block, level, bp);
719 * It's empty, there is no such record.
721 if (!block->bb_numrecs)
724 * Set the ptr value to 1, that's the first record/key.
726 cur->bc_ptrs[level] = 1;
731 * Change the cursor to point to the last record in the current block
732 * at the given level. Other levels are unaffected.
734 STATIC int /* success=1, failure=0 */
736 xfs_btree_cur_t *cur, /* btree cursor */
737 int level) /* level to change */
739 struct xfs_btree_block *block; /* generic btree block pointer */
740 xfs_buf_t *bp; /* buffer containing block */
743 * Get the block pointer for this level.
745 block = xfs_btree_get_block(cur, level, &bp);
746 xfs_btree_check_block(cur, block, level, bp);
748 * It's empty, there is no such record.
750 if (!block->bb_numrecs)
753 * Set the ptr value to numrecs, that's the last record/key.
755 cur->bc_ptrs[level] = be16_to_cpu(block->bb_numrecs);
760 * Compute first and last byte offsets for the fields given.
761 * Interprets the offsets table, which contains struct field offsets.
765 __int64_t fields, /* bitmask of fields */
766 const short *offsets, /* table of field offsets */
767 int nbits, /* number of bits to inspect */
768 int *first, /* output: first byte offset */
769 int *last) /* output: last byte offset */
771 int i; /* current bit number */
772 __int64_t imask; /* mask for current bit number */
776 * Find the lowest bit, so the first byte offset.
778 for (i = 0, imask = 1LL; ; i++, imask <<= 1) {
779 if (imask & fields) {
785 * Find the highest bit, so the last byte offset.
787 for (i = nbits - 1, imask = 1LL << i; ; i--, imask >>= 1) {
788 if (imask & fields) {
789 *last = offsets[i + 1] - 1;
796 * Get a buffer for the block, return it read in.
797 * Long-form addressing.
801 struct xfs_mount *mp, /* file system mount point */
802 struct xfs_trans *tp, /* transaction pointer */
803 xfs_fsblock_t fsbno, /* file system block number */
804 uint lock, /* lock flags for read_buf */
805 struct xfs_buf **bpp, /* buffer for fsbno */
806 int refval, /* ref count value for buffer */
807 const struct xfs_buf_ops *ops)
809 struct xfs_buf *bp; /* return value */
810 xfs_daddr_t d; /* real disk block address */
813 ASSERT(fsbno != NULLFSBLOCK);
814 d = XFS_FSB_TO_DADDR(mp, fsbno);
815 error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, d,
816 mp->m_bsize, lock, &bp, ops);
820 xfs_buf_set_ref(bp, refval);
826 * Read-ahead the block, don't wait for it, don't return a buffer.
827 * Long-form addressing.
831 xfs_btree_reada_bufl(
832 struct xfs_mount *mp, /* file system mount point */
833 xfs_fsblock_t fsbno, /* file system block number */
834 xfs_extlen_t count, /* count of filesystem blocks */
835 const struct xfs_buf_ops *ops)
839 ASSERT(fsbno != NULLFSBLOCK);
840 d = XFS_FSB_TO_DADDR(mp, fsbno);
841 xfs_buf_readahead(mp->m_ddev_targp, d, mp->m_bsize * count, ops);
845 * Read-ahead the block, don't wait for it, don't return a buffer.
846 * Short-form addressing.
850 xfs_btree_reada_bufs(
851 struct xfs_mount *mp, /* file system mount point */
852 xfs_agnumber_t agno, /* allocation group number */
853 xfs_agblock_t agbno, /* allocation group block number */
854 xfs_extlen_t count, /* count of filesystem blocks */
855 const struct xfs_buf_ops *ops)
859 ASSERT(agno != NULLAGNUMBER);
860 ASSERT(agbno != NULLAGBLOCK);
861 d = XFS_AGB_TO_DADDR(mp, agno, agbno);
862 xfs_buf_readahead(mp->m_ddev_targp, d, mp->m_bsize * count, ops);
866 xfs_btree_readahead_lblock(
867 struct xfs_btree_cur *cur,
869 struct xfs_btree_block *block)
872 xfs_fsblock_t left = be64_to_cpu(block->bb_u.l.bb_leftsib);
873 xfs_fsblock_t right = be64_to_cpu(block->bb_u.l.bb_rightsib);
875 if ((lr & XFS_BTCUR_LEFTRA) && left != NULLFSBLOCK) {
876 xfs_btree_reada_bufl(cur->bc_mp, left, 1,
877 cur->bc_ops->buf_ops);
881 if ((lr & XFS_BTCUR_RIGHTRA) && right != NULLFSBLOCK) {
882 xfs_btree_reada_bufl(cur->bc_mp, right, 1,
883 cur->bc_ops->buf_ops);
891 xfs_btree_readahead_sblock(
892 struct xfs_btree_cur *cur,
894 struct xfs_btree_block *block)
897 xfs_agblock_t left = be32_to_cpu(block->bb_u.s.bb_leftsib);
898 xfs_agblock_t right = be32_to_cpu(block->bb_u.s.bb_rightsib);
901 if ((lr & XFS_BTCUR_LEFTRA) && left != NULLAGBLOCK) {
902 xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.a.agno,
903 left, 1, cur->bc_ops->buf_ops);
907 if ((lr & XFS_BTCUR_RIGHTRA) && right != NULLAGBLOCK) {
908 xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.a.agno,
909 right, 1, cur->bc_ops->buf_ops);
917 * Read-ahead btree blocks, at the given level.
918 * Bits in lr are set from XFS_BTCUR_{LEFT,RIGHT}RA.
922 struct xfs_btree_cur *cur, /* btree cursor */
923 int lev, /* level in btree */
924 int lr) /* left/right bits */
926 struct xfs_btree_block *block;
929 * No readahead needed if we are at the root level and the
930 * btree root is stored in the inode.
932 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
933 (lev == cur->bc_nlevels - 1))
936 if ((cur->bc_ra[lev] | lr) == cur->bc_ra[lev])
939 cur->bc_ra[lev] |= lr;
940 block = XFS_BUF_TO_BLOCK(cur->bc_bufs[lev]);
942 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
943 return xfs_btree_readahead_lblock(cur, lr, block);
944 return xfs_btree_readahead_sblock(cur, lr, block);
948 xfs_btree_ptr_to_daddr(
949 struct xfs_btree_cur *cur,
950 union xfs_btree_ptr *ptr)
952 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
953 ASSERT(ptr->l != cpu_to_be64(NULLFSBLOCK));
955 return XFS_FSB_TO_DADDR(cur->bc_mp, be64_to_cpu(ptr->l));
957 ASSERT(cur->bc_private.a.agno != NULLAGNUMBER);
958 ASSERT(ptr->s != cpu_to_be32(NULLAGBLOCK));
960 return XFS_AGB_TO_DADDR(cur->bc_mp, cur->bc_private.a.agno,
961 be32_to_cpu(ptr->s));
966 * Readahead @count btree blocks at the given @ptr location.
968 * We don't need to care about long or short form btrees here as we have a
969 * method of converting the ptr directly to a daddr available to us.
972 xfs_btree_readahead_ptr(
973 struct xfs_btree_cur *cur,
974 union xfs_btree_ptr *ptr,
977 xfs_buf_readahead(cur->bc_mp->m_ddev_targp,
978 xfs_btree_ptr_to_daddr(cur, ptr),
979 cur->bc_mp->m_bsize * count, cur->bc_ops->buf_ops);
983 * Set the buffer for level "lev" in the cursor to bp, releasing
984 * any previous buffer.
988 xfs_btree_cur_t *cur, /* btree cursor */
989 int lev, /* level in btree */
990 xfs_buf_t *bp) /* new buffer to set */
992 struct xfs_btree_block *b; /* btree block */
994 if (cur->bc_bufs[lev])
995 xfs_trans_brelse(cur->bc_tp, cur->bc_bufs[lev]);
996 cur->bc_bufs[lev] = bp;
999 b = XFS_BUF_TO_BLOCK(bp);
1000 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
1001 if (b->bb_u.l.bb_leftsib == cpu_to_be64(NULLFSBLOCK))
1002 cur->bc_ra[lev] |= XFS_BTCUR_LEFTRA;
1003 if (b->bb_u.l.bb_rightsib == cpu_to_be64(NULLFSBLOCK))
1004 cur->bc_ra[lev] |= XFS_BTCUR_RIGHTRA;
1006 if (b->bb_u.s.bb_leftsib == cpu_to_be32(NULLAGBLOCK))
1007 cur->bc_ra[lev] |= XFS_BTCUR_LEFTRA;
1008 if (b->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK))
1009 cur->bc_ra[lev] |= XFS_BTCUR_RIGHTRA;
1014 xfs_btree_ptr_is_null(
1015 struct xfs_btree_cur *cur,
1016 union xfs_btree_ptr *ptr)
1018 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
1019 return ptr->l == cpu_to_be64(NULLFSBLOCK);
1021 return ptr->s == cpu_to_be32(NULLAGBLOCK);
1025 xfs_btree_set_ptr_null(
1026 struct xfs_btree_cur *cur,
1027 union xfs_btree_ptr *ptr)
1029 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
1030 ptr->l = cpu_to_be64(NULLFSBLOCK);
1032 ptr->s = cpu_to_be32(NULLAGBLOCK);
1036 * Get/set/init sibling pointers
1039 xfs_btree_get_sibling(
1040 struct xfs_btree_cur *cur,
1041 struct xfs_btree_block *block,
1042 union xfs_btree_ptr *ptr,
1045 ASSERT(lr == XFS_BB_LEFTSIB || lr == XFS_BB_RIGHTSIB);
1047 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
1048 if (lr == XFS_BB_RIGHTSIB)
1049 ptr->l = block->bb_u.l.bb_rightsib;
1051 ptr->l = block->bb_u.l.bb_leftsib;
1053 if (lr == XFS_BB_RIGHTSIB)
1054 ptr->s = block->bb_u.s.bb_rightsib;
1056 ptr->s = block->bb_u.s.bb_leftsib;
1061 xfs_btree_set_sibling(
1062 struct xfs_btree_cur *cur,
1063 struct xfs_btree_block *block,
1064 union xfs_btree_ptr *ptr,
1067 ASSERT(lr == XFS_BB_LEFTSIB || lr == XFS_BB_RIGHTSIB);
1069 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
1070 if (lr == XFS_BB_RIGHTSIB)
1071 block->bb_u.l.bb_rightsib = ptr->l;
1073 block->bb_u.l.bb_leftsib = ptr->l;
1075 if (lr == XFS_BB_RIGHTSIB)
1076 block->bb_u.s.bb_rightsib = ptr->s;
1078 block->bb_u.s.bb_leftsib = ptr->s;
1083 xfs_btree_init_block_int(
1084 struct xfs_mount *mp,
1085 struct xfs_btree_block *buf,
1093 int crc = xfs_sb_version_hascrc(&mp->m_sb);
1095 buf->bb_magic = cpu_to_be32(magic);
1096 buf->bb_level = cpu_to_be16(level);
1097 buf->bb_numrecs = cpu_to_be16(numrecs);
1099 if (flags & XFS_BTREE_LONG_PTRS) {
1100 buf->bb_u.l.bb_leftsib = cpu_to_be64(NULLFSBLOCK);
1101 buf->bb_u.l.bb_rightsib = cpu_to_be64(NULLFSBLOCK);
1103 buf->bb_u.l.bb_blkno = cpu_to_be64(blkno);
1104 buf->bb_u.l.bb_owner = cpu_to_be64(owner);
1105 uuid_copy(&buf->bb_u.l.bb_uuid, &mp->m_sb.sb_meta_uuid);
1106 buf->bb_u.l.bb_pad = 0;
1107 buf->bb_u.l.bb_lsn = 0;
1110 /* owner is a 32 bit value on short blocks */
1111 __u32 __owner = (__u32)owner;
1113 buf->bb_u.s.bb_leftsib = cpu_to_be32(NULLAGBLOCK);
1114 buf->bb_u.s.bb_rightsib = cpu_to_be32(NULLAGBLOCK);
1116 buf->bb_u.s.bb_blkno = cpu_to_be64(blkno);
1117 buf->bb_u.s.bb_owner = cpu_to_be32(__owner);
1118 uuid_copy(&buf->bb_u.s.bb_uuid, &mp->m_sb.sb_meta_uuid);
1119 buf->bb_u.s.bb_lsn = 0;
1125 xfs_btree_init_block(
1126 struct xfs_mount *mp,
1134 xfs_btree_init_block_int(mp, XFS_BUF_TO_BLOCK(bp), bp->b_bn,
1135 magic, level, numrecs, owner, flags);
1139 xfs_btree_init_block_cur(
1140 struct xfs_btree_cur *cur,
1148 * we can pull the owner from the cursor right now as the different
1149 * owners align directly with the pointer size of the btree. This may
1150 * change in future, but is safe for current users of the generic btree
1153 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
1154 owner = cur->bc_private.b.ip->i_ino;
1156 owner = cur->bc_private.a.agno;
1158 xfs_btree_init_block_int(cur->bc_mp, XFS_BUF_TO_BLOCK(bp), bp->b_bn,
1159 xfs_btree_magic(cur), level, numrecs,
1160 owner, cur->bc_flags);
1164 * Return true if ptr is the last record in the btree and
1165 * we need to track updates to this record. The decision
1166 * will be further refined in the update_lastrec method.
1169 xfs_btree_is_lastrec(
1170 struct xfs_btree_cur *cur,
1171 struct xfs_btree_block *block,
1174 union xfs_btree_ptr ptr;
1178 if (!(cur->bc_flags & XFS_BTREE_LASTREC_UPDATE))
1181 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
1182 if (!xfs_btree_ptr_is_null(cur, &ptr))
1188 xfs_btree_buf_to_ptr(
1189 struct xfs_btree_cur *cur,
1191 union xfs_btree_ptr *ptr)
1193 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
1194 ptr->l = cpu_to_be64(XFS_DADDR_TO_FSB(cur->bc_mp,
1197 ptr->s = cpu_to_be32(xfs_daddr_to_agbno(cur->bc_mp,
1204 struct xfs_btree_cur *cur,
1207 switch (cur->bc_btnum) {
1210 xfs_buf_set_ref(bp, XFS_ALLOC_BTREE_REF);
1213 case XFS_BTNUM_FINO:
1214 xfs_buf_set_ref(bp, XFS_INO_BTREE_REF);
1216 case XFS_BTNUM_BMAP:
1217 xfs_buf_set_ref(bp, XFS_BMAP_BTREE_REF);
1219 case XFS_BTNUM_RMAP:
1220 xfs_buf_set_ref(bp, XFS_RMAP_BTREE_REF);
1222 case XFS_BTNUM_REFC:
1223 xfs_buf_set_ref(bp, XFS_REFC_BTREE_REF);
1231 xfs_btree_get_buf_block(
1232 struct xfs_btree_cur *cur,
1233 union xfs_btree_ptr *ptr,
1235 struct xfs_btree_block **block,
1236 struct xfs_buf **bpp)
1238 struct xfs_mount *mp = cur->bc_mp;
1241 /* need to sort out how callers deal with failures first */
1242 ASSERT(!(flags & XBF_TRYLOCK));
1244 d = xfs_btree_ptr_to_daddr(cur, ptr);
1245 *bpp = xfs_trans_get_buf(cur->bc_tp, mp->m_ddev_targp, d,
1246 mp->m_bsize, flags);
1251 (*bpp)->b_ops = cur->bc_ops->buf_ops;
1252 *block = XFS_BUF_TO_BLOCK(*bpp);
1257 * Read in the buffer at the given ptr and return the buffer and
1258 * the block pointer within the buffer.
1261 xfs_btree_read_buf_block(
1262 struct xfs_btree_cur *cur,
1263 union xfs_btree_ptr *ptr,
1265 struct xfs_btree_block **block,
1266 struct xfs_buf **bpp)
1268 struct xfs_mount *mp = cur->bc_mp;
1272 /* need to sort out how callers deal with failures first */
1273 ASSERT(!(flags & XBF_TRYLOCK));
1275 d = xfs_btree_ptr_to_daddr(cur, ptr);
1276 error = xfs_trans_read_buf(mp, cur->bc_tp, mp->m_ddev_targp, d,
1277 mp->m_bsize, flags, bpp,
1278 cur->bc_ops->buf_ops);
1282 xfs_btree_set_refs(cur, *bpp);
1283 *block = XFS_BUF_TO_BLOCK(*bpp);
1288 * Copy keys from one btree block to another.
1291 xfs_btree_copy_keys(
1292 struct xfs_btree_cur *cur,
1293 union xfs_btree_key *dst_key,
1294 union xfs_btree_key *src_key,
1297 ASSERT(numkeys >= 0);
1298 memcpy(dst_key, src_key, numkeys * cur->bc_ops->key_len);
1302 * Copy records from one btree block to another.
1305 xfs_btree_copy_recs(
1306 struct xfs_btree_cur *cur,
1307 union xfs_btree_rec *dst_rec,
1308 union xfs_btree_rec *src_rec,
1311 ASSERT(numrecs >= 0);
1312 memcpy(dst_rec, src_rec, numrecs * cur->bc_ops->rec_len);
1316 * Copy block pointers from one btree block to another.
1319 xfs_btree_copy_ptrs(
1320 struct xfs_btree_cur *cur,
1321 union xfs_btree_ptr *dst_ptr,
1322 union xfs_btree_ptr *src_ptr,
1325 ASSERT(numptrs >= 0);
1326 memcpy(dst_ptr, src_ptr, numptrs * xfs_btree_ptr_len(cur));
1330 * Shift keys one index left/right inside a single btree block.
1333 xfs_btree_shift_keys(
1334 struct xfs_btree_cur *cur,
1335 union xfs_btree_key *key,
1341 ASSERT(numkeys >= 0);
1342 ASSERT(dir == 1 || dir == -1);
1344 dst_key = (char *)key + (dir * cur->bc_ops->key_len);
1345 memmove(dst_key, key, numkeys * cur->bc_ops->key_len);
1349 * Shift records one index left/right inside a single btree block.
1352 xfs_btree_shift_recs(
1353 struct xfs_btree_cur *cur,
1354 union xfs_btree_rec *rec,
1360 ASSERT(numrecs >= 0);
1361 ASSERT(dir == 1 || dir == -1);
1363 dst_rec = (char *)rec + (dir * cur->bc_ops->rec_len);
1364 memmove(dst_rec, rec, numrecs * cur->bc_ops->rec_len);
1368 * Shift block pointers one index left/right inside a single btree block.
1371 xfs_btree_shift_ptrs(
1372 struct xfs_btree_cur *cur,
1373 union xfs_btree_ptr *ptr,
1379 ASSERT(numptrs >= 0);
1380 ASSERT(dir == 1 || dir == -1);
1382 dst_ptr = (char *)ptr + (dir * xfs_btree_ptr_len(cur));
1383 memmove(dst_ptr, ptr, numptrs * xfs_btree_ptr_len(cur));
1387 * Log key values from the btree block.
1391 struct xfs_btree_cur *cur,
1396 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1397 XFS_BTREE_TRACE_ARGBII(cur, bp, first, last);
1400 xfs_trans_buf_set_type(cur->bc_tp, bp, XFS_BLFT_BTREE_BUF);
1401 xfs_trans_log_buf(cur->bc_tp, bp,
1402 xfs_btree_key_offset(cur, first),
1403 xfs_btree_key_offset(cur, last + 1) - 1);
1405 xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip,
1406 xfs_ilog_fbroot(cur->bc_private.b.whichfork));
1409 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1413 * Log record values from the btree block.
1417 struct xfs_btree_cur *cur,
1422 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1423 XFS_BTREE_TRACE_ARGBII(cur, bp, first, last);
1425 xfs_trans_buf_set_type(cur->bc_tp, bp, XFS_BLFT_BTREE_BUF);
1426 xfs_trans_log_buf(cur->bc_tp, bp,
1427 xfs_btree_rec_offset(cur, first),
1428 xfs_btree_rec_offset(cur, last + 1) - 1);
1430 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1434 * Log block pointer fields from a btree block (nonleaf).
1438 struct xfs_btree_cur *cur, /* btree cursor */
1439 struct xfs_buf *bp, /* buffer containing btree block */
1440 int first, /* index of first pointer to log */
1441 int last) /* index of last pointer to log */
1443 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1444 XFS_BTREE_TRACE_ARGBII(cur, bp, first, last);
1447 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
1448 int level = xfs_btree_get_level(block);
1450 xfs_trans_buf_set_type(cur->bc_tp, bp, XFS_BLFT_BTREE_BUF);
1451 xfs_trans_log_buf(cur->bc_tp, bp,
1452 xfs_btree_ptr_offset(cur, first, level),
1453 xfs_btree_ptr_offset(cur, last + 1, level) - 1);
1455 xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip,
1456 xfs_ilog_fbroot(cur->bc_private.b.whichfork));
1459 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1463 * Log fields from a btree block header.
1466 xfs_btree_log_block(
1467 struct xfs_btree_cur *cur, /* btree cursor */
1468 struct xfs_buf *bp, /* buffer containing btree block */
1469 int fields) /* mask of fields: XFS_BB_... */
1471 int first; /* first byte offset logged */
1472 int last; /* last byte offset logged */
1473 static const short soffsets[] = { /* table of offsets (short) */
1474 offsetof(struct xfs_btree_block, bb_magic),
1475 offsetof(struct xfs_btree_block, bb_level),
1476 offsetof(struct xfs_btree_block, bb_numrecs),
1477 offsetof(struct xfs_btree_block, bb_u.s.bb_leftsib),
1478 offsetof(struct xfs_btree_block, bb_u.s.bb_rightsib),
1479 offsetof(struct xfs_btree_block, bb_u.s.bb_blkno),
1480 offsetof(struct xfs_btree_block, bb_u.s.bb_lsn),
1481 offsetof(struct xfs_btree_block, bb_u.s.bb_uuid),
1482 offsetof(struct xfs_btree_block, bb_u.s.bb_owner),
1483 offsetof(struct xfs_btree_block, bb_u.s.bb_crc),
1484 XFS_BTREE_SBLOCK_CRC_LEN
1486 static const short loffsets[] = { /* table of offsets (long) */
1487 offsetof(struct xfs_btree_block, bb_magic),
1488 offsetof(struct xfs_btree_block, bb_level),
1489 offsetof(struct xfs_btree_block, bb_numrecs),
1490 offsetof(struct xfs_btree_block, bb_u.l.bb_leftsib),
1491 offsetof(struct xfs_btree_block, bb_u.l.bb_rightsib),
1492 offsetof(struct xfs_btree_block, bb_u.l.bb_blkno),
1493 offsetof(struct xfs_btree_block, bb_u.l.bb_lsn),
1494 offsetof(struct xfs_btree_block, bb_u.l.bb_uuid),
1495 offsetof(struct xfs_btree_block, bb_u.l.bb_owner),
1496 offsetof(struct xfs_btree_block, bb_u.l.bb_crc),
1497 offsetof(struct xfs_btree_block, bb_u.l.bb_pad),
1498 XFS_BTREE_LBLOCK_CRC_LEN
1501 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1502 XFS_BTREE_TRACE_ARGBI(cur, bp, fields);
1507 if (cur->bc_flags & XFS_BTREE_CRC_BLOCKS) {
1509 * We don't log the CRC when updating a btree
1510 * block but instead recreate it during log
1511 * recovery. As the log buffers have checksums
1512 * of their own this is safe and avoids logging a crc
1513 * update in a lot of places.
1515 if (fields == XFS_BB_ALL_BITS)
1516 fields = XFS_BB_ALL_BITS_CRC;
1517 nbits = XFS_BB_NUM_BITS_CRC;
1519 nbits = XFS_BB_NUM_BITS;
1521 xfs_btree_offsets(fields,
1522 (cur->bc_flags & XFS_BTREE_LONG_PTRS) ?
1523 loffsets : soffsets,
1524 nbits, &first, &last);
1525 xfs_trans_buf_set_type(cur->bc_tp, bp, XFS_BLFT_BTREE_BUF);
1526 xfs_trans_log_buf(cur->bc_tp, bp, first, last);
1528 xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip,
1529 xfs_ilog_fbroot(cur->bc_private.b.whichfork));
1532 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1536 * Increment cursor by one record at the level.
1537 * For nonzero levels the leaf-ward information is untouched.
1540 xfs_btree_increment(
1541 struct xfs_btree_cur *cur,
1543 int *stat) /* success/failure */
1545 struct xfs_btree_block *block;
1546 union xfs_btree_ptr ptr;
1548 int error; /* error return value */
1551 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1552 XFS_BTREE_TRACE_ARGI(cur, level);
1554 ASSERT(level < cur->bc_nlevels);
1556 /* Read-ahead to the right at this level. */
1557 xfs_btree_readahead(cur, level, XFS_BTCUR_RIGHTRA);
1559 /* Get a pointer to the btree block. */
1560 block = xfs_btree_get_block(cur, level, &bp);
1563 error = xfs_btree_check_block(cur, block, level, bp);
1568 /* We're done if we remain in the block after the increment. */
1569 if (++cur->bc_ptrs[level] <= xfs_btree_get_numrecs(block))
1572 /* Fail if we just went off the right edge of the tree. */
1573 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
1574 if (xfs_btree_ptr_is_null(cur, &ptr))
1577 XFS_BTREE_STATS_INC(cur, increment);
1580 * March up the tree incrementing pointers.
1581 * Stop when we don't go off the right edge of a block.
1583 for (lev = level + 1; lev < cur->bc_nlevels; lev++) {
1584 block = xfs_btree_get_block(cur, lev, &bp);
1587 error = xfs_btree_check_block(cur, block, lev, bp);
1592 if (++cur->bc_ptrs[lev] <= xfs_btree_get_numrecs(block))
1595 /* Read-ahead the right block for the next loop. */
1596 xfs_btree_readahead(cur, lev, XFS_BTCUR_RIGHTRA);
1600 * If we went off the root then we are either seriously
1601 * confused or have the tree root in an inode.
1603 if (lev == cur->bc_nlevels) {
1604 if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE)
1607 error = -EFSCORRUPTED;
1610 ASSERT(lev < cur->bc_nlevels);
1613 * Now walk back down the tree, fixing up the cursor's buffer
1614 * pointers and key numbers.
1616 for (block = xfs_btree_get_block(cur, lev, &bp); lev > level; ) {
1617 union xfs_btree_ptr *ptrp;
1619 ptrp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[lev], block);
1621 error = xfs_btree_read_buf_block(cur, ptrp, 0, &block, &bp);
1625 xfs_btree_setbuf(cur, lev, bp);
1626 cur->bc_ptrs[lev] = 1;
1629 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1634 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1639 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
1644 * Decrement cursor by one record at the level.
1645 * For nonzero levels the leaf-ward information is untouched.
1648 xfs_btree_decrement(
1649 struct xfs_btree_cur *cur,
1651 int *stat) /* success/failure */
1653 struct xfs_btree_block *block;
1655 int error; /* error return value */
1657 union xfs_btree_ptr ptr;
1659 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1660 XFS_BTREE_TRACE_ARGI(cur, level);
1662 ASSERT(level < cur->bc_nlevels);
1664 /* Read-ahead to the left at this level. */
1665 xfs_btree_readahead(cur, level, XFS_BTCUR_LEFTRA);
1667 /* We're done if we remain in the block after the decrement. */
1668 if (--cur->bc_ptrs[level] > 0)
1671 /* Get a pointer to the btree block. */
1672 block = xfs_btree_get_block(cur, level, &bp);
1675 error = xfs_btree_check_block(cur, block, level, bp);
1680 /* Fail if we just went off the left edge of the tree. */
1681 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_LEFTSIB);
1682 if (xfs_btree_ptr_is_null(cur, &ptr))
1685 XFS_BTREE_STATS_INC(cur, decrement);
1688 * March up the tree decrementing pointers.
1689 * Stop when we don't go off the left edge of a block.
1691 for (lev = level + 1; lev < cur->bc_nlevels; lev++) {
1692 if (--cur->bc_ptrs[lev] > 0)
1694 /* Read-ahead the left block for the next loop. */
1695 xfs_btree_readahead(cur, lev, XFS_BTCUR_LEFTRA);
1699 * If we went off the root then we are seriously confused.
1700 * or the root of the tree is in an inode.
1702 if (lev == cur->bc_nlevels) {
1703 if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE)
1706 error = -EFSCORRUPTED;
1709 ASSERT(lev < cur->bc_nlevels);
1712 * Now walk back down the tree, fixing up the cursor's buffer
1713 * pointers and key numbers.
1715 for (block = xfs_btree_get_block(cur, lev, &bp); lev > level; ) {
1716 union xfs_btree_ptr *ptrp;
1718 ptrp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[lev], block);
1720 error = xfs_btree_read_buf_block(cur, ptrp, 0, &block, &bp);
1723 xfs_btree_setbuf(cur, lev, bp);
1724 cur->bc_ptrs[lev] = xfs_btree_get_numrecs(block);
1727 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1732 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1737 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
1742 xfs_btree_lookup_get_block(
1743 struct xfs_btree_cur *cur, /* btree cursor */
1744 int level, /* level in the btree */
1745 union xfs_btree_ptr *pp, /* ptr to btree block */
1746 struct xfs_btree_block **blkp) /* return btree block */
1748 struct xfs_buf *bp; /* buffer pointer for btree block */
1751 /* special case the root block if in an inode */
1752 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
1753 (level == cur->bc_nlevels - 1)) {
1754 *blkp = xfs_btree_get_iroot(cur);
1759 * If the old buffer at this level for the disk address we are
1760 * looking for re-use it.
1762 * Otherwise throw it away and get a new one.
1764 bp = cur->bc_bufs[level];
1765 if (bp && XFS_BUF_ADDR(bp) == xfs_btree_ptr_to_daddr(cur, pp)) {
1766 *blkp = XFS_BUF_TO_BLOCK(bp);
1770 error = xfs_btree_read_buf_block(cur, pp, 0, blkp, &bp);
1774 /* Check the inode owner since the verifiers don't. */
1775 if (xfs_sb_version_hascrc(&cur->bc_mp->m_sb) &&
1776 (cur->bc_flags & XFS_BTREE_LONG_PTRS) &&
1777 be64_to_cpu((*blkp)->bb_u.l.bb_owner) !=
1778 cur->bc_private.b.ip->i_ino)
1781 /* Did we get the level we were looking for? */
1782 if (be16_to_cpu((*blkp)->bb_level) != level)
1785 /* Check that internal nodes have at least one record. */
1786 if (level != 0 && be16_to_cpu((*blkp)->bb_numrecs) == 0)
1789 xfs_btree_setbuf(cur, level, bp);
1794 xfs_trans_brelse(cur->bc_tp, bp);
1795 return -EFSCORRUPTED;
1799 * Get current search key. For level 0 we don't actually have a key
1800 * structure so we make one up from the record. For all other levels
1801 * we just return the right key.
1803 STATIC union xfs_btree_key *
1804 xfs_lookup_get_search_key(
1805 struct xfs_btree_cur *cur,
1808 struct xfs_btree_block *block,
1809 union xfs_btree_key *kp)
1812 cur->bc_ops->init_key_from_rec(kp,
1813 xfs_btree_rec_addr(cur, keyno, block));
1817 return xfs_btree_key_addr(cur, keyno, block);
1821 * Lookup the record. The cursor is made to point to it, based on dir.
1822 * stat is set to 0 if can't find any such record, 1 for success.
1826 struct xfs_btree_cur *cur, /* btree cursor */
1827 xfs_lookup_t dir, /* <=, ==, or >= */
1828 int *stat) /* success/failure */
1830 struct xfs_btree_block *block; /* current btree block */
1831 __int64_t diff; /* difference for the current key */
1832 int error; /* error return value */
1833 int keyno; /* current key number */
1834 int level; /* level in the btree */
1835 union xfs_btree_ptr *pp; /* ptr to btree block */
1836 union xfs_btree_ptr ptr; /* ptr to btree block */
1838 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1839 XFS_BTREE_TRACE_ARGI(cur, dir);
1841 XFS_BTREE_STATS_INC(cur, lookup);
1843 /* No such thing as a zero-level tree. */
1844 if (cur->bc_nlevels == 0)
1845 return -EFSCORRUPTED;
1850 /* initialise start pointer from cursor */
1851 cur->bc_ops->init_ptr_from_cur(cur, &ptr);
1855 * Iterate over each level in the btree, starting at the root.
1856 * For each level above the leaves, find the key we need, based
1857 * on the lookup record, then follow the corresponding block
1858 * pointer down to the next level.
1860 for (level = cur->bc_nlevels - 1, diff = 1; level >= 0; level--) {
1861 /* Get the block we need to do the lookup on. */
1862 error = xfs_btree_lookup_get_block(cur, level, pp, &block);
1868 * If we already had a key match at a higher level, we
1869 * know we need to use the first entry in this block.
1873 /* Otherwise search this block. Do a binary search. */
1875 int high; /* high entry number */
1876 int low; /* low entry number */
1878 /* Set low and high entry numbers, 1-based. */
1880 high = xfs_btree_get_numrecs(block);
1882 /* Block is empty, must be an empty leaf. */
1883 ASSERT(level == 0 && cur->bc_nlevels == 1);
1885 cur->bc_ptrs[0] = dir != XFS_LOOKUP_LE;
1886 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1891 /* Binary search the block. */
1892 while (low <= high) {
1893 union xfs_btree_key key;
1894 union xfs_btree_key *kp;
1896 XFS_BTREE_STATS_INC(cur, compare);
1898 /* keyno is average of low and high. */
1899 keyno = (low + high) >> 1;
1901 /* Get current search key */
1902 kp = xfs_lookup_get_search_key(cur, level,
1903 keyno, block, &key);
1906 * Compute difference to get next direction:
1907 * - less than, move right
1908 * - greater than, move left
1909 * - equal, we're done
1911 diff = cur->bc_ops->key_diff(cur, kp);
1922 * If there are more levels, set up for the next level
1923 * by getting the block number and filling in the cursor.
1927 * If we moved left, need the previous key number,
1928 * unless there isn't one.
1930 if (diff > 0 && --keyno < 1)
1932 pp = xfs_btree_ptr_addr(cur, keyno, block);
1935 error = xfs_btree_check_ptr(cur, pp, 0, level);
1939 cur->bc_ptrs[level] = keyno;
1943 /* Done with the search. See if we need to adjust the results. */
1944 if (dir != XFS_LOOKUP_LE && diff < 0) {
1947 * If ge search and we went off the end of the block, but it's
1948 * not the last block, we're in the wrong block.
1950 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
1951 if (dir == XFS_LOOKUP_GE &&
1952 keyno > xfs_btree_get_numrecs(block) &&
1953 !xfs_btree_ptr_is_null(cur, &ptr)) {
1956 cur->bc_ptrs[0] = keyno;
1957 error = xfs_btree_increment(cur, 0, &i);
1960 XFS_WANT_CORRUPTED_RETURN(cur->bc_mp, i == 1);
1961 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1965 } else if (dir == XFS_LOOKUP_LE && diff > 0)
1967 cur->bc_ptrs[0] = keyno;
1969 /* Return if we succeeded or not. */
1970 if (keyno == 0 || keyno > xfs_btree_get_numrecs(block))
1972 else if (dir != XFS_LOOKUP_EQ || diff == 0)
1976 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1980 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
1984 /* Find the high key storage area from a regular key. */
1985 STATIC union xfs_btree_key *
1986 xfs_btree_high_key_from_key(
1987 struct xfs_btree_cur *cur,
1988 union xfs_btree_key *key)
1990 ASSERT(cur->bc_flags & XFS_BTREE_OVERLAPPING);
1991 return (union xfs_btree_key *)((char *)key +
1992 (cur->bc_ops->key_len / 2));
1995 /* Determine the low (and high if overlapped) keys of a leaf block */
1997 xfs_btree_get_leaf_keys(
1998 struct xfs_btree_cur *cur,
1999 struct xfs_btree_block *block,
2000 union xfs_btree_key *key)
2002 union xfs_btree_key max_hkey;
2003 union xfs_btree_key hkey;
2004 union xfs_btree_rec *rec;
2005 union xfs_btree_key *high;
2008 rec = xfs_btree_rec_addr(cur, 1, block);
2009 cur->bc_ops->init_key_from_rec(key, rec);
2011 if (cur->bc_flags & XFS_BTREE_OVERLAPPING) {
2013 cur->bc_ops->init_high_key_from_rec(&max_hkey, rec);
2014 for (n = 2; n <= xfs_btree_get_numrecs(block); n++) {
2015 rec = xfs_btree_rec_addr(cur, n, block);
2016 cur->bc_ops->init_high_key_from_rec(&hkey, rec);
2017 if (cur->bc_ops->diff_two_keys(cur, &hkey, &max_hkey)
2022 high = xfs_btree_high_key_from_key(cur, key);
2023 memcpy(high, &max_hkey, cur->bc_ops->key_len / 2);
2027 /* Determine the low (and high if overlapped) keys of a node block */
2029 xfs_btree_get_node_keys(
2030 struct xfs_btree_cur *cur,
2031 struct xfs_btree_block *block,
2032 union xfs_btree_key *key)
2034 union xfs_btree_key *hkey;
2035 union xfs_btree_key *max_hkey;
2036 union xfs_btree_key *high;
2039 if (cur->bc_flags & XFS_BTREE_OVERLAPPING) {
2040 memcpy(key, xfs_btree_key_addr(cur, 1, block),
2041 cur->bc_ops->key_len / 2);
2043 max_hkey = xfs_btree_high_key_addr(cur, 1, block);
2044 for (n = 2; n <= xfs_btree_get_numrecs(block); n++) {
2045 hkey = xfs_btree_high_key_addr(cur, n, block);
2046 if (cur->bc_ops->diff_two_keys(cur, hkey, max_hkey) > 0)
2050 high = xfs_btree_high_key_from_key(cur, key);
2051 memcpy(high, max_hkey, cur->bc_ops->key_len / 2);
2053 memcpy(key, xfs_btree_key_addr(cur, 1, block),
2054 cur->bc_ops->key_len);
2058 /* Derive the keys for any btree block. */
2061 struct xfs_btree_cur *cur,
2062 struct xfs_btree_block *block,
2063 union xfs_btree_key *key)
2065 if (be16_to_cpu(block->bb_level) == 0)
2066 xfs_btree_get_leaf_keys(cur, block, key);
2068 xfs_btree_get_node_keys(cur, block, key);
2072 * Decide if we need to update the parent keys of a btree block. For
2073 * a standard btree this is only necessary if we're updating the first
2074 * record/key. For an overlapping btree, we must always update the
2075 * keys because the highest key can be in any of the records or keys
2079 xfs_btree_needs_key_update(
2080 struct xfs_btree_cur *cur,
2083 return (cur->bc_flags & XFS_BTREE_OVERLAPPING) || ptr == 1;
2087 * Update the low and high parent keys of the given level, progressing
2088 * towards the root. If force_all is false, stop if the keys for a given
2089 * level do not need updating.
2092 __xfs_btree_updkeys(
2093 struct xfs_btree_cur *cur,
2095 struct xfs_btree_block *block,
2096 struct xfs_buf *bp0,
2099 union xfs_btree_key key; /* keys from current level */
2100 union xfs_btree_key *lkey; /* keys from the next level up */
2101 union xfs_btree_key *hkey;
2102 union xfs_btree_key *nlkey; /* keys from the next level up */
2103 union xfs_btree_key *nhkey;
2107 ASSERT(cur->bc_flags & XFS_BTREE_OVERLAPPING);
2109 /* Exit if there aren't any parent levels to update. */
2110 if (level + 1 >= cur->bc_nlevels)
2113 trace_xfs_btree_updkeys(cur, level, bp0);
2116 hkey = xfs_btree_high_key_from_key(cur, lkey);
2117 xfs_btree_get_keys(cur, block, lkey);
2118 for (level++; level < cur->bc_nlevels; level++) {
2122 block = xfs_btree_get_block(cur, level, &bp);
2123 trace_xfs_btree_updkeys(cur, level, bp);
2125 error = xfs_btree_check_block(cur, block, level, bp);
2127 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2131 ptr = cur->bc_ptrs[level];
2132 nlkey = xfs_btree_key_addr(cur, ptr, block);
2133 nhkey = xfs_btree_high_key_addr(cur, ptr, block);
2135 !(cur->bc_ops->diff_two_keys(cur, nlkey, lkey) != 0 ||
2136 cur->bc_ops->diff_two_keys(cur, nhkey, hkey) != 0))
2138 xfs_btree_copy_keys(cur, nlkey, lkey, 1);
2139 xfs_btree_log_keys(cur, bp, ptr, ptr);
2140 if (level + 1 >= cur->bc_nlevels)
2142 xfs_btree_get_node_keys(cur, block, lkey);
2148 /* Update all the keys from some level in cursor back to the root. */
2150 xfs_btree_updkeys_force(
2151 struct xfs_btree_cur *cur,
2155 struct xfs_btree_block *block;
2157 block = xfs_btree_get_block(cur, level, &bp);
2158 return __xfs_btree_updkeys(cur, level, block, bp, true);
2162 * Update the parent keys of the given level, progressing towards the root.
2165 xfs_btree_update_keys(
2166 struct xfs_btree_cur *cur,
2169 struct xfs_btree_block *block;
2171 union xfs_btree_key *kp;
2172 union xfs_btree_key key;
2177 block = xfs_btree_get_block(cur, level, &bp);
2178 if (cur->bc_flags & XFS_BTREE_OVERLAPPING)
2179 return __xfs_btree_updkeys(cur, level, block, bp, false);
2181 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2182 XFS_BTREE_TRACE_ARGIK(cur, level, keyp);
2185 * Go up the tree from this level toward the root.
2186 * At each level, update the key value to the value input.
2187 * Stop when we reach a level where the cursor isn't pointing
2188 * at the first entry in the block.
2190 xfs_btree_get_keys(cur, block, &key);
2191 for (level++, ptr = 1; ptr == 1 && level < cur->bc_nlevels; level++) {
2195 block = xfs_btree_get_block(cur, level, &bp);
2197 error = xfs_btree_check_block(cur, block, level, bp);
2199 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2203 ptr = cur->bc_ptrs[level];
2204 kp = xfs_btree_key_addr(cur, ptr, block);
2205 xfs_btree_copy_keys(cur, kp, &key, 1);
2206 xfs_btree_log_keys(cur, bp, ptr, ptr);
2209 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2214 * Update the record referred to by cur to the value in the
2215 * given record. This either works (return 0) or gets an
2216 * EFSCORRUPTED error.
2220 struct xfs_btree_cur *cur,
2221 union xfs_btree_rec *rec)
2223 struct xfs_btree_block *block;
2227 union xfs_btree_rec *rp;
2229 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2230 XFS_BTREE_TRACE_ARGR(cur, rec);
2232 /* Pick up the current block. */
2233 block = xfs_btree_get_block(cur, 0, &bp);
2236 error = xfs_btree_check_block(cur, block, 0, bp);
2240 /* Get the address of the rec to be updated. */
2241 ptr = cur->bc_ptrs[0];
2242 rp = xfs_btree_rec_addr(cur, ptr, block);
2244 /* Fill in the new contents and log them. */
2245 xfs_btree_copy_recs(cur, rp, rec, 1);
2246 xfs_btree_log_recs(cur, bp, ptr, ptr);
2249 * If we are tracking the last record in the tree and
2250 * we are at the far right edge of the tree, update it.
2252 if (xfs_btree_is_lastrec(cur, block, 0)) {
2253 cur->bc_ops->update_lastrec(cur, block, rec,
2254 ptr, LASTREC_UPDATE);
2257 /* Pass new key value up to our parent. */
2258 if (xfs_btree_needs_key_update(cur, ptr)) {
2259 error = xfs_btree_update_keys(cur, 0);
2264 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2268 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2273 * Move 1 record left from cur/level if possible.
2274 * Update cur to reflect the new path.
2276 STATIC int /* error */
2278 struct xfs_btree_cur *cur,
2280 int *stat) /* success/failure */
2282 struct xfs_buf *lbp; /* left buffer pointer */
2283 struct xfs_btree_block *left; /* left btree block */
2284 int lrecs; /* left record count */
2285 struct xfs_buf *rbp; /* right buffer pointer */
2286 struct xfs_btree_block *right; /* right btree block */
2287 struct xfs_btree_cur *tcur; /* temporary btree cursor */
2288 int rrecs; /* right record count */
2289 union xfs_btree_ptr lptr; /* left btree pointer */
2290 union xfs_btree_key *rkp = NULL; /* right btree key */
2291 union xfs_btree_ptr *rpp = NULL; /* right address pointer */
2292 union xfs_btree_rec *rrp = NULL; /* right record pointer */
2293 int error; /* error return value */
2296 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2297 XFS_BTREE_TRACE_ARGI(cur, level);
2299 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
2300 level == cur->bc_nlevels - 1)
2303 /* Set up variables for this block as "right". */
2304 right = xfs_btree_get_block(cur, level, &rbp);
2307 error = xfs_btree_check_block(cur, right, level, rbp);
2312 /* If we've got no left sibling then we can't shift an entry left. */
2313 xfs_btree_get_sibling(cur, right, &lptr, XFS_BB_LEFTSIB);
2314 if (xfs_btree_ptr_is_null(cur, &lptr))
2318 * If the cursor entry is the one that would be moved, don't
2319 * do it... it's too complicated.
2321 if (cur->bc_ptrs[level] <= 1)
2324 /* Set up the left neighbor as "left". */
2325 error = xfs_btree_read_buf_block(cur, &lptr, 0, &left, &lbp);
2329 /* If it's full, it can't take another entry. */
2330 lrecs = xfs_btree_get_numrecs(left);
2331 if (lrecs == cur->bc_ops->get_maxrecs(cur, level))
2334 rrecs = xfs_btree_get_numrecs(right);
2337 * We add one entry to the left side and remove one for the right side.
2338 * Account for it here, the changes will be updated on disk and logged
2344 XFS_BTREE_STATS_INC(cur, lshift);
2345 XFS_BTREE_STATS_ADD(cur, moves, 1);
2348 * If non-leaf, copy a key and a ptr to the left block.
2349 * Log the changes to the left block.
2352 /* It's a non-leaf. Move keys and pointers. */
2353 union xfs_btree_key *lkp; /* left btree key */
2354 union xfs_btree_ptr *lpp; /* left address pointer */
2356 lkp = xfs_btree_key_addr(cur, lrecs, left);
2357 rkp = xfs_btree_key_addr(cur, 1, right);
2359 lpp = xfs_btree_ptr_addr(cur, lrecs, left);
2360 rpp = xfs_btree_ptr_addr(cur, 1, right);
2362 error = xfs_btree_check_ptr(cur, rpp, 0, level);
2366 xfs_btree_copy_keys(cur, lkp, rkp, 1);
2367 xfs_btree_copy_ptrs(cur, lpp, rpp, 1);
2369 xfs_btree_log_keys(cur, lbp, lrecs, lrecs);
2370 xfs_btree_log_ptrs(cur, lbp, lrecs, lrecs);
2372 ASSERT(cur->bc_ops->keys_inorder(cur,
2373 xfs_btree_key_addr(cur, lrecs - 1, left), lkp));
2375 /* It's a leaf. Move records. */
2376 union xfs_btree_rec *lrp; /* left record pointer */
2378 lrp = xfs_btree_rec_addr(cur, lrecs, left);
2379 rrp = xfs_btree_rec_addr(cur, 1, right);
2381 xfs_btree_copy_recs(cur, lrp, rrp, 1);
2382 xfs_btree_log_recs(cur, lbp, lrecs, lrecs);
2384 ASSERT(cur->bc_ops->recs_inorder(cur,
2385 xfs_btree_rec_addr(cur, lrecs - 1, left), lrp));
2388 xfs_btree_set_numrecs(left, lrecs);
2389 xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS);
2391 xfs_btree_set_numrecs(right, rrecs);
2392 xfs_btree_log_block(cur, rbp, XFS_BB_NUMRECS);
2395 * Slide the contents of right down one entry.
2397 XFS_BTREE_STATS_ADD(cur, moves, rrecs - 1);
2399 /* It's a nonleaf. operate on keys and ptrs */
2401 int i; /* loop index */
2403 for (i = 0; i < rrecs; i++) {
2404 error = xfs_btree_check_ptr(cur, rpp, i + 1, level);
2409 xfs_btree_shift_keys(cur,
2410 xfs_btree_key_addr(cur, 2, right),
2412 xfs_btree_shift_ptrs(cur,
2413 xfs_btree_ptr_addr(cur, 2, right),
2416 xfs_btree_log_keys(cur, rbp, 1, rrecs);
2417 xfs_btree_log_ptrs(cur, rbp, 1, rrecs);
2419 /* It's a leaf. operate on records */
2420 xfs_btree_shift_recs(cur,
2421 xfs_btree_rec_addr(cur, 2, right),
2423 xfs_btree_log_recs(cur, rbp, 1, rrecs);
2427 * Using a temporary cursor, update the parent key values of the
2428 * block on the left.
2430 if (cur->bc_flags & XFS_BTREE_OVERLAPPING) {
2431 error = xfs_btree_dup_cursor(cur, &tcur);
2434 i = xfs_btree_firstrec(tcur, level);
2435 XFS_WANT_CORRUPTED_GOTO(tcur->bc_mp, i == 1, error0);
2437 error = xfs_btree_decrement(tcur, level, &i);
2441 /* Update the parent high keys of the left block, if needed. */
2442 error = xfs_btree_update_keys(tcur, level);
2446 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
2449 /* Update the parent keys of the right block. */
2450 error = xfs_btree_update_keys(cur, level);
2454 /* Slide the cursor value left one. */
2455 cur->bc_ptrs[level]--;
2457 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2462 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2467 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2471 XFS_BTREE_TRACE_CURSOR(tcur, XBT_ERROR);
2472 xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
2477 * Move 1 record right from cur/level if possible.
2478 * Update cur to reflect the new path.
2480 STATIC int /* error */
2482 struct xfs_btree_cur *cur,
2484 int *stat) /* success/failure */
2486 struct xfs_buf *lbp; /* left buffer pointer */
2487 struct xfs_btree_block *left; /* left btree block */
2488 struct xfs_buf *rbp; /* right buffer pointer */
2489 struct xfs_btree_block *right; /* right btree block */
2490 struct xfs_btree_cur *tcur; /* temporary btree cursor */
2491 union xfs_btree_ptr rptr; /* right block pointer */
2492 union xfs_btree_key *rkp; /* right btree key */
2493 int rrecs; /* right record count */
2494 int lrecs; /* left record count */
2495 int error; /* error return value */
2496 int i; /* loop counter */
2498 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2499 XFS_BTREE_TRACE_ARGI(cur, level);
2501 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
2502 (level == cur->bc_nlevels - 1))
2505 /* Set up variables for this block as "left". */
2506 left = xfs_btree_get_block(cur, level, &lbp);
2509 error = xfs_btree_check_block(cur, left, level, lbp);
2514 /* If we've got no right sibling then we can't shift an entry right. */
2515 xfs_btree_get_sibling(cur, left, &rptr, XFS_BB_RIGHTSIB);
2516 if (xfs_btree_ptr_is_null(cur, &rptr))
2520 * If the cursor entry is the one that would be moved, don't
2521 * do it... it's too complicated.
2523 lrecs = xfs_btree_get_numrecs(left);
2524 if (cur->bc_ptrs[level] >= lrecs)
2527 /* Set up the right neighbor as "right". */
2528 error = xfs_btree_read_buf_block(cur, &rptr, 0, &right, &rbp);
2532 /* If it's full, it can't take another entry. */
2533 rrecs = xfs_btree_get_numrecs(right);
2534 if (rrecs == cur->bc_ops->get_maxrecs(cur, level))
2537 XFS_BTREE_STATS_INC(cur, rshift);
2538 XFS_BTREE_STATS_ADD(cur, moves, rrecs);
2541 * Make a hole at the start of the right neighbor block, then
2542 * copy the last left block entry to the hole.
2545 /* It's a nonleaf. make a hole in the keys and ptrs */
2546 union xfs_btree_key *lkp;
2547 union xfs_btree_ptr *lpp;
2548 union xfs_btree_ptr *rpp;
2550 lkp = xfs_btree_key_addr(cur, lrecs, left);
2551 lpp = xfs_btree_ptr_addr(cur, lrecs, left);
2552 rkp = xfs_btree_key_addr(cur, 1, right);
2553 rpp = xfs_btree_ptr_addr(cur, 1, right);
2556 for (i = rrecs - 1; i >= 0; i--) {
2557 error = xfs_btree_check_ptr(cur, rpp, i, level);
2563 xfs_btree_shift_keys(cur, rkp, 1, rrecs);
2564 xfs_btree_shift_ptrs(cur, rpp, 1, rrecs);
2567 error = xfs_btree_check_ptr(cur, lpp, 0, level);
2572 /* Now put the new data in, and log it. */
2573 xfs_btree_copy_keys(cur, rkp, lkp, 1);
2574 xfs_btree_copy_ptrs(cur, rpp, lpp, 1);
2576 xfs_btree_log_keys(cur, rbp, 1, rrecs + 1);
2577 xfs_btree_log_ptrs(cur, rbp, 1, rrecs + 1);
2579 ASSERT(cur->bc_ops->keys_inorder(cur, rkp,
2580 xfs_btree_key_addr(cur, 2, right)));
2582 /* It's a leaf. make a hole in the records */
2583 union xfs_btree_rec *lrp;
2584 union xfs_btree_rec *rrp;
2586 lrp = xfs_btree_rec_addr(cur, lrecs, left);
2587 rrp = xfs_btree_rec_addr(cur, 1, right);
2589 xfs_btree_shift_recs(cur, rrp, 1, rrecs);
2591 /* Now put the new data in, and log it. */
2592 xfs_btree_copy_recs(cur, rrp, lrp, 1);
2593 xfs_btree_log_recs(cur, rbp, 1, rrecs + 1);
2597 * Decrement and log left's numrecs, bump and log right's numrecs.
2599 xfs_btree_set_numrecs(left, --lrecs);
2600 xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS);
2602 xfs_btree_set_numrecs(right, ++rrecs);
2603 xfs_btree_log_block(cur, rbp, XFS_BB_NUMRECS);
2606 * Using a temporary cursor, update the parent key values of the
2607 * block on the right.
2609 error = xfs_btree_dup_cursor(cur, &tcur);
2612 i = xfs_btree_lastrec(tcur, level);
2613 XFS_WANT_CORRUPTED_GOTO(tcur->bc_mp, i == 1, error0);
2615 error = xfs_btree_increment(tcur, level, &i);
2619 /* Update the parent high keys of the left block, if needed. */
2620 if (cur->bc_flags & XFS_BTREE_OVERLAPPING) {
2621 error = xfs_btree_update_keys(cur, level);
2626 /* Update the parent keys of the right block. */
2627 error = xfs_btree_update_keys(tcur, level);
2631 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
2633 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2638 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2643 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2647 XFS_BTREE_TRACE_CURSOR(tcur, XBT_ERROR);
2648 xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
2653 * Split cur/level block in half.
2654 * Return new block number and the key to its first
2655 * record (to be inserted into parent).
2657 STATIC int /* error */
2659 struct xfs_btree_cur *cur,
2661 union xfs_btree_ptr *ptrp,
2662 union xfs_btree_key *key,
2663 struct xfs_btree_cur **curp,
2664 int *stat) /* success/failure */
2666 union xfs_btree_ptr lptr; /* left sibling block ptr */
2667 struct xfs_buf *lbp; /* left buffer pointer */
2668 struct xfs_btree_block *left; /* left btree block */
2669 union xfs_btree_ptr rptr; /* right sibling block ptr */
2670 struct xfs_buf *rbp; /* right buffer pointer */
2671 struct xfs_btree_block *right; /* right btree block */
2672 union xfs_btree_ptr rrptr; /* right-right sibling ptr */
2673 struct xfs_buf *rrbp; /* right-right buffer pointer */
2674 struct xfs_btree_block *rrblock; /* right-right btree block */
2678 int error; /* error return value */
2683 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2684 XFS_BTREE_TRACE_ARGIPK(cur, level, *ptrp, key);
2686 XFS_BTREE_STATS_INC(cur, split);
2688 /* Set up left block (current one). */
2689 left = xfs_btree_get_block(cur, level, &lbp);
2692 error = xfs_btree_check_block(cur, left, level, lbp);
2697 xfs_btree_buf_to_ptr(cur, lbp, &lptr);
2699 /* Allocate the new block. If we can't do it, we're toast. Give up. */
2700 error = cur->bc_ops->alloc_block(cur, &lptr, &rptr, stat);
2705 XFS_BTREE_STATS_INC(cur, alloc);
2707 /* Set up the new block as "right". */
2708 error = xfs_btree_get_buf_block(cur, &rptr, 0, &right, &rbp);
2712 /* Fill in the btree header for the new right block. */
2713 xfs_btree_init_block_cur(cur, rbp, xfs_btree_get_level(left), 0);
2716 * Split the entries between the old and the new block evenly.
2717 * Make sure that if there's an odd number of entries now, that
2718 * each new block will have the same number of entries.
2720 lrecs = xfs_btree_get_numrecs(left);
2722 if ((lrecs & 1) && cur->bc_ptrs[level] <= rrecs + 1)
2724 src_index = (lrecs - rrecs + 1);
2726 XFS_BTREE_STATS_ADD(cur, moves, rrecs);
2728 /* Adjust numrecs for the later get_*_keys() calls. */
2730 xfs_btree_set_numrecs(left, lrecs);
2731 xfs_btree_set_numrecs(right, xfs_btree_get_numrecs(right) + rrecs);
2734 * Copy btree block entries from the left block over to the
2735 * new block, the right. Update the right block and log the
2739 /* It's a non-leaf. Move keys and pointers. */
2740 union xfs_btree_key *lkp; /* left btree key */
2741 union xfs_btree_ptr *lpp; /* left address pointer */
2742 union xfs_btree_key *rkp; /* right btree key */
2743 union xfs_btree_ptr *rpp; /* right address pointer */
2745 lkp = xfs_btree_key_addr(cur, src_index, left);
2746 lpp = xfs_btree_ptr_addr(cur, src_index, left);
2747 rkp = xfs_btree_key_addr(cur, 1, right);
2748 rpp = xfs_btree_ptr_addr(cur, 1, right);
2751 for (i = src_index; i < rrecs; i++) {
2752 error = xfs_btree_check_ptr(cur, lpp, i, level);
2758 /* Copy the keys & pointers to the new block. */
2759 xfs_btree_copy_keys(cur, rkp, lkp, rrecs);
2760 xfs_btree_copy_ptrs(cur, rpp, lpp, rrecs);
2762 xfs_btree_log_keys(cur, rbp, 1, rrecs);
2763 xfs_btree_log_ptrs(cur, rbp, 1, rrecs);
2765 /* Stash the keys of the new block for later insertion. */
2766 xfs_btree_get_node_keys(cur, right, key);
2768 /* It's a leaf. Move records. */
2769 union xfs_btree_rec *lrp; /* left record pointer */
2770 union xfs_btree_rec *rrp; /* right record pointer */
2772 lrp = xfs_btree_rec_addr(cur, src_index, left);
2773 rrp = xfs_btree_rec_addr(cur, 1, right);
2775 /* Copy records to the new block. */
2776 xfs_btree_copy_recs(cur, rrp, lrp, rrecs);
2777 xfs_btree_log_recs(cur, rbp, 1, rrecs);
2779 /* Stash the keys of the new block for later insertion. */
2780 xfs_btree_get_leaf_keys(cur, right, key);
2784 * Find the left block number by looking in the buffer.
2785 * Adjust sibling pointers.
2787 xfs_btree_get_sibling(cur, left, &rrptr, XFS_BB_RIGHTSIB);
2788 xfs_btree_set_sibling(cur, right, &rrptr, XFS_BB_RIGHTSIB);
2789 xfs_btree_set_sibling(cur, right, &lptr, XFS_BB_LEFTSIB);
2790 xfs_btree_set_sibling(cur, left, &rptr, XFS_BB_RIGHTSIB);
2792 xfs_btree_log_block(cur, rbp, XFS_BB_ALL_BITS);
2793 xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS | XFS_BB_RIGHTSIB);
2796 * If there's a block to the new block's right, make that block
2797 * point back to right instead of to left.
2799 if (!xfs_btree_ptr_is_null(cur, &rrptr)) {
2800 error = xfs_btree_read_buf_block(cur, &rrptr,
2801 0, &rrblock, &rrbp);
2804 xfs_btree_set_sibling(cur, rrblock, &rptr, XFS_BB_LEFTSIB);
2805 xfs_btree_log_block(cur, rrbp, XFS_BB_LEFTSIB);
2808 /* Update the parent high keys of the left block, if needed. */
2809 if (cur->bc_flags & XFS_BTREE_OVERLAPPING) {
2810 error = xfs_btree_update_keys(cur, level);
2816 * If the cursor is really in the right block, move it there.
2817 * If it's just pointing past the last entry in left, then we'll
2818 * insert there, so don't change anything in that case.
2820 if (cur->bc_ptrs[level] > lrecs + 1) {
2821 xfs_btree_setbuf(cur, level, rbp);
2822 cur->bc_ptrs[level] -= lrecs;
2825 * If there are more levels, we'll need another cursor which refers
2826 * the right block, no matter where this cursor was.
2828 if (level + 1 < cur->bc_nlevels) {
2829 error = xfs_btree_dup_cursor(cur, curp);
2832 (*curp)->bc_ptrs[level + 1]++;
2835 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2839 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2844 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2848 struct xfs_btree_split_args {
2849 struct xfs_btree_cur *cur;
2851 union xfs_btree_ptr *ptrp;
2852 union xfs_btree_key *key;
2853 struct xfs_btree_cur **curp;
2854 int *stat; /* success/failure */
2856 bool kswapd; /* allocation in kswapd context */
2857 struct completion *done;
2858 struct work_struct work;
2862 * Stack switching interfaces for allocation
2865 xfs_btree_split_worker(
2866 struct work_struct *work)
2868 struct xfs_btree_split_args *args = container_of(work,
2869 struct xfs_btree_split_args, work);
2870 unsigned long pflags;
2871 unsigned long new_pflags = PF_FSTRANS;
2874 * we are in a transaction context here, but may also be doing work
2875 * in kswapd context, and hence we may need to inherit that state
2876 * temporarily to ensure that we don't block waiting for memory reclaim
2880 new_pflags |= PF_MEMALLOC | PF_SWAPWRITE | PF_KSWAPD;
2882 current_set_flags_nested(&pflags, new_pflags);
2884 args->result = __xfs_btree_split(args->cur, args->level, args->ptrp,
2885 args->key, args->curp, args->stat);
2886 complete(args->done);
2888 current_restore_flags_nested(&pflags, new_pflags);
2892 * BMBT split requests often come in with little stack to work on. Push
2893 * them off to a worker thread so there is lots of stack to use. For the other
2894 * btree types, just call directly to avoid the context switch overhead here.
2896 STATIC int /* error */
2898 struct xfs_btree_cur *cur,
2900 union xfs_btree_ptr *ptrp,
2901 union xfs_btree_key *key,
2902 struct xfs_btree_cur **curp,
2903 int *stat) /* success/failure */
2905 struct xfs_btree_split_args args;
2906 DECLARE_COMPLETION_ONSTACK(done);
2908 if (cur->bc_btnum != XFS_BTNUM_BMAP)
2909 return __xfs_btree_split(cur, level, ptrp, key, curp, stat);
2918 args.kswapd = current_is_kswapd();
2919 INIT_WORK_ONSTACK(&args.work, xfs_btree_split_worker);
2920 queue_work(xfs_alloc_wq, &args.work);
2921 wait_for_completion(&done);
2922 destroy_work_on_stack(&args.work);
2928 * Copy the old inode root contents into a real block and make the
2929 * broot point to it.
2932 xfs_btree_new_iroot(
2933 struct xfs_btree_cur *cur, /* btree cursor */
2934 int *logflags, /* logging flags for inode */
2935 int *stat) /* return status - 0 fail */
2937 struct xfs_buf *cbp; /* buffer for cblock */
2938 struct xfs_btree_block *block; /* btree block */
2939 struct xfs_btree_block *cblock; /* child btree block */
2940 union xfs_btree_key *ckp; /* child key pointer */
2941 union xfs_btree_ptr *cpp; /* child ptr pointer */
2942 union xfs_btree_key *kp; /* pointer to btree key */
2943 union xfs_btree_ptr *pp; /* pointer to block addr */
2944 union xfs_btree_ptr nptr; /* new block addr */
2945 int level; /* btree level */
2946 int error; /* error return code */
2948 int i; /* loop counter */
2951 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2952 XFS_BTREE_STATS_INC(cur, newroot);
2954 ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE);
2956 level = cur->bc_nlevels - 1;
2958 block = xfs_btree_get_iroot(cur);
2959 pp = xfs_btree_ptr_addr(cur, 1, block);
2961 /* Allocate the new block. If we can't do it, we're toast. Give up. */
2962 error = cur->bc_ops->alloc_block(cur, pp, &nptr, stat);
2966 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2969 XFS_BTREE_STATS_INC(cur, alloc);
2971 /* Copy the root into a real block. */
2972 error = xfs_btree_get_buf_block(cur, &nptr, 0, &cblock, &cbp);
2977 * we can't just memcpy() the root in for CRC enabled btree blocks.
2978 * In that case have to also ensure the blkno remains correct
2980 memcpy(cblock, block, xfs_btree_block_len(cur));
2981 if (cur->bc_flags & XFS_BTREE_CRC_BLOCKS) {
2982 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
2983 cblock->bb_u.l.bb_blkno = cpu_to_be64(cbp->b_bn);
2985 cblock->bb_u.s.bb_blkno = cpu_to_be64(cbp->b_bn);
2988 be16_add_cpu(&block->bb_level, 1);
2989 xfs_btree_set_numrecs(block, 1);
2991 cur->bc_ptrs[level + 1] = 1;
2993 kp = xfs_btree_key_addr(cur, 1, block);
2994 ckp = xfs_btree_key_addr(cur, 1, cblock);
2995 xfs_btree_copy_keys(cur, ckp, kp, xfs_btree_get_numrecs(cblock));
2997 cpp = xfs_btree_ptr_addr(cur, 1, cblock);
2999 for (i = 0; i < be16_to_cpu(cblock->bb_numrecs); i++) {
3000 error = xfs_btree_check_ptr(cur, pp, i, level);
3005 xfs_btree_copy_ptrs(cur, cpp, pp, xfs_btree_get_numrecs(cblock));
3008 error = xfs_btree_check_ptr(cur, &nptr, 0, level);
3012 xfs_btree_copy_ptrs(cur, pp, &nptr, 1);
3014 xfs_iroot_realloc(cur->bc_private.b.ip,
3015 1 - xfs_btree_get_numrecs(cblock),
3016 cur->bc_private.b.whichfork);
3018 xfs_btree_setbuf(cur, level, cbp);
3021 * Do all this logging at the end so that
3022 * the root is at the right level.
3024 xfs_btree_log_block(cur, cbp, XFS_BB_ALL_BITS);
3025 xfs_btree_log_keys(cur, cbp, 1, be16_to_cpu(cblock->bb_numrecs));
3026 xfs_btree_log_ptrs(cur, cbp, 1, be16_to_cpu(cblock->bb_numrecs));
3029 XFS_ILOG_CORE | xfs_ilog_fbroot(cur->bc_private.b.whichfork);
3031 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3034 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3039 * Allocate a new root block, fill it in.
3041 STATIC int /* error */
3043 struct xfs_btree_cur *cur, /* btree cursor */
3044 int *stat) /* success/failure */
3046 struct xfs_btree_block *block; /* one half of the old root block */
3047 struct xfs_buf *bp; /* buffer containing block */
3048 int error; /* error return value */
3049 struct xfs_buf *lbp; /* left buffer pointer */
3050 struct xfs_btree_block *left; /* left btree block */
3051 struct xfs_buf *nbp; /* new (root) buffer */
3052 struct xfs_btree_block *new; /* new (root) btree block */
3053 int nptr; /* new value for key index, 1 or 2 */
3054 struct xfs_buf *rbp; /* right buffer pointer */
3055 struct xfs_btree_block *right; /* right btree block */
3056 union xfs_btree_ptr rptr;
3057 union xfs_btree_ptr lptr;
3059 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
3060 XFS_BTREE_STATS_INC(cur, newroot);
3062 /* initialise our start point from the cursor */
3063 cur->bc_ops->init_ptr_from_cur(cur, &rptr);
3065 /* Allocate the new block. If we can't do it, we're toast. Give up. */
3066 error = cur->bc_ops->alloc_block(cur, &rptr, &lptr, stat);
3071 XFS_BTREE_STATS_INC(cur, alloc);
3073 /* Set up the new block. */
3074 error = xfs_btree_get_buf_block(cur, &lptr, 0, &new, &nbp);
3078 /* Set the root in the holding structure increasing the level by 1. */
3079 cur->bc_ops->set_root(cur, &lptr, 1);
3082 * At the previous root level there are now two blocks: the old root,
3083 * and the new block generated when it was split. We don't know which
3084 * one the cursor is pointing at, so we set up variables "left" and
3085 * "right" for each case.
3087 block = xfs_btree_get_block(cur, cur->bc_nlevels - 1, &bp);
3090 error = xfs_btree_check_block(cur, block, cur->bc_nlevels - 1, bp);
3095 xfs_btree_get_sibling(cur, block, &rptr, XFS_BB_RIGHTSIB);
3096 if (!xfs_btree_ptr_is_null(cur, &rptr)) {
3097 /* Our block is left, pick up the right block. */
3099 xfs_btree_buf_to_ptr(cur, lbp, &lptr);
3101 error = xfs_btree_read_buf_block(cur, &rptr, 0, &right, &rbp);
3107 /* Our block is right, pick up the left block. */
3109 xfs_btree_buf_to_ptr(cur, rbp, &rptr);
3111 xfs_btree_get_sibling(cur, right, &lptr, XFS_BB_LEFTSIB);
3112 error = xfs_btree_read_buf_block(cur, &lptr, 0, &left, &lbp);
3119 /* Fill in the new block's btree header and log it. */
3120 xfs_btree_init_block_cur(cur, nbp, cur->bc_nlevels, 2);
3121 xfs_btree_log_block(cur, nbp, XFS_BB_ALL_BITS);
3122 ASSERT(!xfs_btree_ptr_is_null(cur, &lptr) &&
3123 !xfs_btree_ptr_is_null(cur, &rptr));
3125 /* Fill in the key data in the new root. */
3126 if (xfs_btree_get_level(left) > 0) {
3128 * Get the keys for the left block's keys and put them directly
3129 * in the parent block. Do the same for the right block.
3131 xfs_btree_get_node_keys(cur, left,
3132 xfs_btree_key_addr(cur, 1, new));
3133 xfs_btree_get_node_keys(cur, right,
3134 xfs_btree_key_addr(cur, 2, new));
3137 * Get the keys for the left block's records and put them
3138 * directly in the parent block. Do the same for the right
3141 xfs_btree_get_leaf_keys(cur, left,
3142 xfs_btree_key_addr(cur, 1, new));
3143 xfs_btree_get_leaf_keys(cur, right,
3144 xfs_btree_key_addr(cur, 2, new));
3146 xfs_btree_log_keys(cur, nbp, 1, 2);
3148 /* Fill in the pointer data in the new root. */
3149 xfs_btree_copy_ptrs(cur,
3150 xfs_btree_ptr_addr(cur, 1, new), &lptr, 1);
3151 xfs_btree_copy_ptrs(cur,
3152 xfs_btree_ptr_addr(cur, 2, new), &rptr, 1);
3153 xfs_btree_log_ptrs(cur, nbp, 1, 2);
3155 /* Fix up the cursor. */
3156 xfs_btree_setbuf(cur, cur->bc_nlevels, nbp);
3157 cur->bc_ptrs[cur->bc_nlevels] = nptr;
3159 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3163 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3166 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3172 xfs_btree_make_block_unfull(
3173 struct xfs_btree_cur *cur, /* btree cursor */
3174 int level, /* btree level */
3175 int numrecs,/* # of recs in block */
3176 int *oindex,/* old tree index */
3177 int *index, /* new tree index */
3178 union xfs_btree_ptr *nptr, /* new btree ptr */
3179 struct xfs_btree_cur **ncur, /* new btree cursor */
3180 union xfs_btree_key *key, /* key of new block */
3185 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
3186 level == cur->bc_nlevels - 1) {
3187 struct xfs_inode *ip = cur->bc_private.b.ip;
3189 if (numrecs < cur->bc_ops->get_dmaxrecs(cur, level)) {
3190 /* A root block that can be made bigger. */
3191 xfs_iroot_realloc(ip, 1, cur->bc_private.b.whichfork);
3194 /* A root block that needs replacing */
3197 error = xfs_btree_new_iroot(cur, &logflags, stat);
3198 if (error || *stat == 0)
3201 xfs_trans_log_inode(cur->bc_tp, ip, logflags);
3207 /* First, try shifting an entry to the right neighbor. */
3208 error = xfs_btree_rshift(cur, level, stat);
3212 /* Next, try shifting an entry to the left neighbor. */
3213 error = xfs_btree_lshift(cur, level, stat);
3218 *oindex = *index = cur->bc_ptrs[level];
3223 * Next, try splitting the current block in half.
3225 * If this works we have to re-set our variables because we
3226 * could be in a different block now.
3228 error = xfs_btree_split(cur, level, nptr, key, ncur, stat);
3229 if (error || *stat == 0)
3233 *index = cur->bc_ptrs[level];
3238 * Insert one record/level. Return information to the caller
3239 * allowing the next level up to proceed if necessary.
3243 struct xfs_btree_cur *cur, /* btree cursor */
3244 int level, /* level to insert record at */
3245 union xfs_btree_ptr *ptrp, /* i/o: block number inserted */
3246 union xfs_btree_rec *rec, /* record to insert */
3247 union xfs_btree_key *key, /* i/o: block key for ptrp */
3248 struct xfs_btree_cur **curp, /* output: new cursor replacing cur */
3249 int *stat) /* success/failure */
3251 struct xfs_btree_block *block; /* btree block */
3252 struct xfs_buf *bp; /* buffer for block */
3253 union xfs_btree_ptr nptr; /* new block ptr */
3254 struct xfs_btree_cur *ncur; /* new btree cursor */
3255 union xfs_btree_key nkey; /* new block key */
3256 union xfs_btree_key *lkey;
3257 int optr; /* old key/record index */
3258 int ptr; /* key/record index */
3259 int numrecs;/* number of records */
3260 int error; /* error return value */
3266 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
3267 XFS_BTREE_TRACE_ARGIPR(cur, level, *ptrp, &rec);
3273 * If we have an external root pointer, and we've made it to the
3274 * root level, allocate a new root block and we're done.
3276 if (!(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
3277 (level >= cur->bc_nlevels)) {
3278 error = xfs_btree_new_root(cur, stat);
3279 xfs_btree_set_ptr_null(cur, ptrp);
3281 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3285 /* If we're off the left edge, return failure. */
3286 ptr = cur->bc_ptrs[level];
3288 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3295 XFS_BTREE_STATS_INC(cur, insrec);
3297 /* Get pointers to the btree buffer and block. */
3298 block = xfs_btree_get_block(cur, level, &bp);
3299 old_bn = bp ? bp->b_bn : XFS_BUF_DADDR_NULL;
3300 numrecs = xfs_btree_get_numrecs(block);
3303 error = xfs_btree_check_block(cur, block, level, bp);
3307 /* Check that the new entry is being inserted in the right place. */
3308 if (ptr <= numrecs) {
3310 ASSERT(cur->bc_ops->recs_inorder(cur, rec,
3311 xfs_btree_rec_addr(cur, ptr, block)));
3313 ASSERT(cur->bc_ops->keys_inorder(cur, key,
3314 xfs_btree_key_addr(cur, ptr, block)));
3320 * If the block is full, we can't insert the new entry until we
3321 * make the block un-full.
3323 xfs_btree_set_ptr_null(cur, &nptr);
3324 if (numrecs == cur->bc_ops->get_maxrecs(cur, level)) {
3325 error = xfs_btree_make_block_unfull(cur, level, numrecs,
3326 &optr, &ptr, &nptr, &ncur, lkey, stat);
3327 if (error || *stat == 0)
3332 * The current block may have changed if the block was
3333 * previously full and we have just made space in it.
3335 block = xfs_btree_get_block(cur, level, &bp);
3336 numrecs = xfs_btree_get_numrecs(block);
3339 error = xfs_btree_check_block(cur, block, level, bp);
3345 * At this point we know there's room for our new entry in the block
3346 * we're pointing at.
3348 XFS_BTREE_STATS_ADD(cur, moves, numrecs - ptr + 1);
3351 /* It's a nonleaf. make a hole in the keys and ptrs */
3352 union xfs_btree_key *kp;
3353 union xfs_btree_ptr *pp;
3355 kp = xfs_btree_key_addr(cur, ptr, block);
3356 pp = xfs_btree_ptr_addr(cur, ptr, block);
3359 for (i = numrecs - ptr; i >= 0; i--) {
3360 error = xfs_btree_check_ptr(cur, pp, i, level);
3366 xfs_btree_shift_keys(cur, kp, 1, numrecs - ptr + 1);
3367 xfs_btree_shift_ptrs(cur, pp, 1, numrecs - ptr + 1);
3370 error = xfs_btree_check_ptr(cur, ptrp, 0, level);
3375 /* Now put the new data in, bump numrecs and log it. */
3376 xfs_btree_copy_keys(cur, kp, key, 1);
3377 xfs_btree_copy_ptrs(cur, pp, ptrp, 1);
3379 xfs_btree_set_numrecs(block, numrecs);
3380 xfs_btree_log_ptrs(cur, bp, ptr, numrecs);
3381 xfs_btree_log_keys(cur, bp, ptr, numrecs);
3383 if (ptr < numrecs) {
3384 ASSERT(cur->bc_ops->keys_inorder(cur, kp,
3385 xfs_btree_key_addr(cur, ptr + 1, block)));
3389 /* It's a leaf. make a hole in the records */
3390 union xfs_btree_rec *rp;
3392 rp = xfs_btree_rec_addr(cur, ptr, block);
3394 xfs_btree_shift_recs(cur, rp, 1, numrecs - ptr + 1);
3396 /* Now put the new data in, bump numrecs and log it. */
3397 xfs_btree_copy_recs(cur, rp, rec, 1);
3398 xfs_btree_set_numrecs(block, ++numrecs);
3399 xfs_btree_log_recs(cur, bp, ptr, numrecs);
3401 if (ptr < numrecs) {
3402 ASSERT(cur->bc_ops->recs_inorder(cur, rp,
3403 xfs_btree_rec_addr(cur, ptr + 1, block)));
3408 /* Log the new number of records in the btree header. */
3409 xfs_btree_log_block(cur, bp, XFS_BB_NUMRECS);
3412 * If we just inserted into a new tree block, we have to
3413 * recalculate nkey here because nkey is out of date.
3415 * Otherwise we're just updating an existing block (having shoved
3416 * some records into the new tree block), so use the regular key
3419 if (bp && bp->b_bn != old_bn) {
3420 xfs_btree_get_keys(cur, block, lkey);
3421 } else if (xfs_btree_needs_key_update(cur, optr)) {
3422 error = xfs_btree_update_keys(cur, level);
3428 * If we are tracking the last record in the tree and
3429 * we are at the far right edge of the tree, update it.
3431 if (xfs_btree_is_lastrec(cur, block, level)) {
3432 cur->bc_ops->update_lastrec(cur, block, rec,
3433 ptr, LASTREC_INSREC);
3437 * Return the new block number, if any.
3438 * If there is one, give back a record value and a cursor too.
3441 if (!xfs_btree_ptr_is_null(cur, &nptr)) {
3442 xfs_btree_copy_keys(cur, key, lkey, 1);
3446 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3451 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3456 * Insert the record at the point referenced by cur.
3458 * A multi-level split of the tree on insert will invalidate the original
3459 * cursor. All callers of this function should assume that the cursor is
3460 * no longer valid and revalidate it.
3464 struct xfs_btree_cur *cur,
3467 int error; /* error return value */
3468 int i; /* result value, 0 for failure */
3469 int level; /* current level number in btree */
3470 union xfs_btree_ptr nptr; /* new block number (split result) */
3471 struct xfs_btree_cur *ncur; /* new cursor (split result) */
3472 struct xfs_btree_cur *pcur; /* previous level's cursor */
3473 union xfs_btree_key bkey; /* key of block to insert */
3474 union xfs_btree_key *key;
3475 union xfs_btree_rec rec; /* record to insert */
3482 xfs_btree_set_ptr_null(cur, &nptr);
3484 /* Make a key out of the record data to be inserted, and save it. */
3485 cur->bc_ops->init_rec_from_cur(cur, &rec);
3486 cur->bc_ops->init_key_from_rec(key, &rec);
3489 * Loop going up the tree, starting at the leaf level.
3490 * Stop when we don't get a split block, that must mean that
3491 * the insert is finished with this level.
3495 * Insert nrec/nptr into this level of the tree.
3496 * Note if we fail, nptr will be null.
3498 error = xfs_btree_insrec(pcur, level, &nptr, &rec, key,
3502 xfs_btree_del_cursor(pcur, XFS_BTREE_ERROR);
3506 XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0);
3510 * See if the cursor we just used is trash.
3511 * Can't trash the caller's cursor, but otherwise we should
3512 * if ncur is a new cursor or we're about to be done.
3515 (ncur || xfs_btree_ptr_is_null(cur, &nptr))) {
3516 /* Save the state from the cursor before we trash it */
3517 if (cur->bc_ops->update_cursor)
3518 cur->bc_ops->update_cursor(pcur, cur);
3519 cur->bc_nlevels = pcur->bc_nlevels;
3520 xfs_btree_del_cursor(pcur, XFS_BTREE_NOERROR);
3522 /* If we got a new cursor, switch to it. */
3527 } while (!xfs_btree_ptr_is_null(cur, &nptr));
3529 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3533 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3538 * Try to merge a non-leaf block back into the inode root.
3540 * Note: the killroot names comes from the fact that we're effectively
3541 * killing the old root block. But because we can't just delete the
3542 * inode we have to copy the single block it was pointing to into the
3546 xfs_btree_kill_iroot(
3547 struct xfs_btree_cur *cur)
3549 int whichfork = cur->bc_private.b.whichfork;
3550 struct xfs_inode *ip = cur->bc_private.b.ip;
3551 struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, whichfork);
3552 struct xfs_btree_block *block;
3553 struct xfs_btree_block *cblock;
3554 union xfs_btree_key *kp;
3555 union xfs_btree_key *ckp;
3556 union xfs_btree_ptr *pp;
3557 union xfs_btree_ptr *cpp;
3558 struct xfs_buf *cbp;
3564 union xfs_btree_ptr ptr;
3568 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
3570 ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE);
3571 ASSERT(cur->bc_nlevels > 1);
3574 * Don't deal with the root block needs to be a leaf case.
3575 * We're just going to turn the thing back into extents anyway.
3577 level = cur->bc_nlevels - 1;
3582 * Give up if the root has multiple children.
3584 block = xfs_btree_get_iroot(cur);
3585 if (xfs_btree_get_numrecs(block) != 1)
3588 cblock = xfs_btree_get_block(cur, level - 1, &cbp);
3589 numrecs = xfs_btree_get_numrecs(cblock);
3592 * Only do this if the next level will fit.
3593 * Then the data must be copied up to the inode,
3594 * instead of freeing the root you free the next level.
3596 if (numrecs > cur->bc_ops->get_dmaxrecs(cur, level))
3599 XFS_BTREE_STATS_INC(cur, killroot);
3602 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_LEFTSIB);
3603 ASSERT(xfs_btree_ptr_is_null(cur, &ptr));
3604 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
3605 ASSERT(xfs_btree_ptr_is_null(cur, &ptr));
3608 index = numrecs - cur->bc_ops->get_maxrecs(cur, level);
3610 xfs_iroot_realloc(cur->bc_private.b.ip, index,
3611 cur->bc_private.b.whichfork);
3612 block = ifp->if_broot;
3615 be16_add_cpu(&block->bb_numrecs, index);
3616 ASSERT(block->bb_numrecs == cblock->bb_numrecs);
3618 kp = xfs_btree_key_addr(cur, 1, block);
3619 ckp = xfs_btree_key_addr(cur, 1, cblock);
3620 xfs_btree_copy_keys(cur, kp, ckp, numrecs);
3622 pp = xfs_btree_ptr_addr(cur, 1, block);
3623 cpp = xfs_btree_ptr_addr(cur, 1, cblock);
3625 for (i = 0; i < numrecs; i++) {
3626 error = xfs_btree_check_ptr(cur, cpp, i, level - 1);
3628 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3633 xfs_btree_copy_ptrs(cur, pp, cpp, numrecs);
3635 error = xfs_btree_free_block(cur, cbp);
3637 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3641 cur->bc_bufs[level - 1] = NULL;
3642 be16_add_cpu(&block->bb_level, -1);
3643 xfs_trans_log_inode(cur->bc_tp, ip,
3644 XFS_ILOG_CORE | xfs_ilog_fbroot(cur->bc_private.b.whichfork));
3647 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3652 * Kill the current root node, and replace it with it's only child node.
3655 xfs_btree_kill_root(
3656 struct xfs_btree_cur *cur,
3659 union xfs_btree_ptr *newroot)
3663 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
3664 XFS_BTREE_STATS_INC(cur, killroot);
3667 * Update the root pointer, decreasing the level by 1 and then
3668 * free the old root.
3670 cur->bc_ops->set_root(cur, newroot, -1);
3672 error = xfs_btree_free_block(cur, bp);
3674 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3678 cur->bc_bufs[level] = NULL;
3679 cur->bc_ra[level] = 0;
3682 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3687 xfs_btree_dec_cursor(
3688 struct xfs_btree_cur *cur,
3696 error = xfs_btree_decrement(cur, level, &i);
3701 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3707 * Single level of the btree record deletion routine.
3708 * Delete record pointed to by cur/level.
3709 * Remove the record from its block then rebalance the tree.
3710 * Return 0 for error, 1 for done, 2 to go on to the next level.
3712 STATIC int /* error */
3714 struct xfs_btree_cur *cur, /* btree cursor */
3715 int level, /* level removing record from */
3716 int *stat) /* fail/done/go-on */
3718 struct xfs_btree_block *block; /* btree block */
3719 union xfs_btree_ptr cptr; /* current block ptr */
3720 struct xfs_buf *bp; /* buffer for block */
3721 int error; /* error return value */
3722 int i; /* loop counter */
3723 union xfs_btree_ptr lptr; /* left sibling block ptr */
3724 struct xfs_buf *lbp; /* left buffer pointer */
3725 struct xfs_btree_block *left; /* left btree block */
3726 int lrecs = 0; /* left record count */
3727 int ptr; /* key/record index */
3728 union xfs_btree_ptr rptr; /* right sibling block ptr */
3729 struct xfs_buf *rbp; /* right buffer pointer */
3730 struct xfs_btree_block *right; /* right btree block */
3731 struct xfs_btree_block *rrblock; /* right-right btree block */
3732 struct xfs_buf *rrbp; /* right-right buffer pointer */
3733 int rrecs = 0; /* right record count */
3734 struct xfs_btree_cur *tcur; /* temporary btree cursor */
3735 int numrecs; /* temporary numrec count */
3737 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
3738 XFS_BTREE_TRACE_ARGI(cur, level);
3742 /* Get the index of the entry being deleted, check for nothing there. */
3743 ptr = cur->bc_ptrs[level];
3745 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3750 /* Get the buffer & block containing the record or key/ptr. */
3751 block = xfs_btree_get_block(cur, level, &bp);
3752 numrecs = xfs_btree_get_numrecs(block);
3755 error = xfs_btree_check_block(cur, block, level, bp);
3760 /* Fail if we're off the end of the block. */
3761 if (ptr > numrecs) {
3762 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3767 XFS_BTREE_STATS_INC(cur, delrec);
3768 XFS_BTREE_STATS_ADD(cur, moves, numrecs - ptr);
3770 /* Excise the entries being deleted. */
3772 /* It's a nonleaf. operate on keys and ptrs */
3773 union xfs_btree_key *lkp;
3774 union xfs_btree_ptr *lpp;
3776 lkp = xfs_btree_key_addr(cur, ptr + 1, block);
3777 lpp = xfs_btree_ptr_addr(cur, ptr + 1, block);
3780 for (i = 0; i < numrecs - ptr; i++) {
3781 error = xfs_btree_check_ptr(cur, lpp, i, level);
3787 if (ptr < numrecs) {
3788 xfs_btree_shift_keys(cur, lkp, -1, numrecs - ptr);
3789 xfs_btree_shift_ptrs(cur, lpp, -1, numrecs - ptr);
3790 xfs_btree_log_keys(cur, bp, ptr, numrecs - 1);
3791 xfs_btree_log_ptrs(cur, bp, ptr, numrecs - 1);
3794 /* It's a leaf. operate on records */
3795 if (ptr < numrecs) {
3796 xfs_btree_shift_recs(cur,
3797 xfs_btree_rec_addr(cur, ptr + 1, block),
3799 xfs_btree_log_recs(cur, bp, ptr, numrecs - 1);
3804 * Decrement and log the number of entries in the block.
3806 xfs_btree_set_numrecs(block, --numrecs);
3807 xfs_btree_log_block(cur, bp, XFS_BB_NUMRECS);
3810 * If we are tracking the last record in the tree and
3811 * we are at the far right edge of the tree, update it.
3813 if (xfs_btree_is_lastrec(cur, block, level)) {
3814 cur->bc_ops->update_lastrec(cur, block, NULL,
3815 ptr, LASTREC_DELREC);
3819 * We're at the root level. First, shrink the root block in-memory.
3820 * Try to get rid of the next level down. If we can't then there's
3821 * nothing left to do.
3823 if (level == cur->bc_nlevels - 1) {
3824 if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) {
3825 xfs_iroot_realloc(cur->bc_private.b.ip, -1,
3826 cur->bc_private.b.whichfork);
3828 error = xfs_btree_kill_iroot(cur);
3832 error = xfs_btree_dec_cursor(cur, level, stat);
3840 * If this is the root level, and there's only one entry left,
3841 * and it's NOT the leaf level, then we can get rid of this
3844 if (numrecs == 1 && level > 0) {
3845 union xfs_btree_ptr *pp;
3847 * pp is still set to the first pointer in the block.
3848 * Make it the new root of the btree.
3850 pp = xfs_btree_ptr_addr(cur, 1, block);
3851 error = xfs_btree_kill_root(cur, bp, level, pp);
3854 } else if (level > 0) {
3855 error = xfs_btree_dec_cursor(cur, level, stat);
3864 * If we deleted the leftmost entry in the block, update the
3865 * key values above us in the tree.
3867 if (xfs_btree_needs_key_update(cur, ptr)) {
3868 error = xfs_btree_update_keys(cur, level);
3874 * If the number of records remaining in the block is at least
3875 * the minimum, we're done.
3877 if (numrecs >= cur->bc_ops->get_minrecs(cur, level)) {
3878 error = xfs_btree_dec_cursor(cur, level, stat);
3885 * Otherwise, we have to move some records around to keep the
3886 * tree balanced. Look at the left and right sibling blocks to
3887 * see if we can re-balance by moving only one record.
3889 xfs_btree_get_sibling(cur, block, &rptr, XFS_BB_RIGHTSIB);
3890 xfs_btree_get_sibling(cur, block, &lptr, XFS_BB_LEFTSIB);
3892 if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) {
3894 * One child of root, need to get a chance to copy its contents
3895 * into the root and delete it. Can't go up to next level,
3896 * there's nothing to delete there.
3898 if (xfs_btree_ptr_is_null(cur, &rptr) &&
3899 xfs_btree_ptr_is_null(cur, &lptr) &&
3900 level == cur->bc_nlevels - 2) {
3901 error = xfs_btree_kill_iroot(cur);
3903 error = xfs_btree_dec_cursor(cur, level, stat);
3910 ASSERT(!xfs_btree_ptr_is_null(cur, &rptr) ||
3911 !xfs_btree_ptr_is_null(cur, &lptr));
3914 * Duplicate the cursor so our btree manipulations here won't
3915 * disrupt the next level up.
3917 error = xfs_btree_dup_cursor(cur, &tcur);
3922 * If there's a right sibling, see if it's ok to shift an entry
3925 if (!xfs_btree_ptr_is_null(cur, &rptr)) {
3927 * Move the temp cursor to the last entry in the next block.
3928 * Actually any entry but the first would suffice.
3930 i = xfs_btree_lastrec(tcur, level);
3931 XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0);
3933 error = xfs_btree_increment(tcur, level, &i);
3936 XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0);
3938 i = xfs_btree_lastrec(tcur, level);
3939 XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0);
3941 /* Grab a pointer to the block. */
3942 right = xfs_btree_get_block(tcur, level, &rbp);
3944 error = xfs_btree_check_block(tcur, right, level, rbp);
3948 /* Grab the current block number, for future use. */
3949 xfs_btree_get_sibling(tcur, right, &cptr, XFS_BB_LEFTSIB);
3952 * If right block is full enough so that removing one entry
3953 * won't make it too empty, and left-shifting an entry out
3954 * of right to us works, we're done.
3956 if (xfs_btree_get_numrecs(right) - 1 >=
3957 cur->bc_ops->get_minrecs(tcur, level)) {
3958 error = xfs_btree_lshift(tcur, level, &i);
3962 ASSERT(xfs_btree_get_numrecs(block) >=
3963 cur->bc_ops->get_minrecs(tcur, level));
3965 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
3968 error = xfs_btree_dec_cursor(cur, level, stat);
3976 * Otherwise, grab the number of records in right for
3977 * future reference, and fix up the temp cursor to point
3978 * to our block again (last record).
3980 rrecs = xfs_btree_get_numrecs(right);
3981 if (!xfs_btree_ptr_is_null(cur, &lptr)) {
3982 i = xfs_btree_firstrec(tcur, level);
3983 XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0);
3985 error = xfs_btree_decrement(tcur, level, &i);
3988 XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0);
3993 * If there's a left sibling, see if it's ok to shift an entry
3996 if (!xfs_btree_ptr_is_null(cur, &lptr)) {
3998 * Move the temp cursor to the first entry in the
4001 i = xfs_btree_firstrec(tcur, level);
4002 XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0);
4004 error = xfs_btree_decrement(tcur, level, &i);
4007 i = xfs_btree_firstrec(tcur, level);
4008 XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, error0);
4010 /* Grab a pointer to the block. */
4011 left = xfs_btree_get_block(tcur, level, &lbp);
4013 error = xfs_btree_check_block(cur, left, level, lbp);
4017 /* Grab the current block number, for future use. */
4018 xfs_btree_get_sibling(tcur, left, &cptr, XFS_BB_RIGHTSIB);
4021 * If left block is full enough so that removing one entry
4022 * won't make it too empty, and right-shifting an entry out
4023 * of left to us works, we're done.
4025 if (xfs_btree_get_numrecs(left) - 1 >=
4026 cur->bc_ops->get_minrecs(tcur, level)) {
4027 error = xfs_btree_rshift(tcur, level, &i);
4031 ASSERT(xfs_btree_get_numrecs(block) >=
4032 cur->bc_ops->get_minrecs(tcur, level));
4033 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
4037 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
4044 * Otherwise, grab the number of records in right for
4047 lrecs = xfs_btree_get_numrecs(left);
4050 /* Delete the temp cursor, we're done with it. */
4051 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
4054 /* If here, we need to do a join to keep the tree balanced. */
4055 ASSERT(!xfs_btree_ptr_is_null(cur, &cptr));
4057 if (!xfs_btree_ptr_is_null(cur, &lptr) &&
4058 lrecs + xfs_btree_get_numrecs(block) <=
4059 cur->bc_ops->get_maxrecs(cur, level)) {
4061 * Set "right" to be the starting block,
4062 * "left" to be the left neighbor.
4067 error = xfs_btree_read_buf_block(cur, &lptr, 0, &left, &lbp);
4072 * If that won't work, see if we can join with the right neighbor block.
4074 } else if (!xfs_btree_ptr_is_null(cur, &rptr) &&
4075 rrecs + xfs_btree_get_numrecs(block) <=
4076 cur->bc_ops->get_maxrecs(cur, level)) {
4078 * Set "left" to be the starting block,
4079 * "right" to be the right neighbor.
4084 error = xfs_btree_read_buf_block(cur, &rptr, 0, &right, &rbp);
4089 * Otherwise, we can't fix the imbalance.
4090 * Just return. This is probably a logic error, but it's not fatal.
4093 error = xfs_btree_dec_cursor(cur, level, stat);
4099 rrecs = xfs_btree_get_numrecs(right);
4100 lrecs = xfs_btree_get_numrecs(left);
4103 * We're now going to join "left" and "right" by moving all the stuff
4104 * in "right" to "left" and deleting "right".
4106 XFS_BTREE_STATS_ADD(cur, moves, rrecs);
4108 /* It's a non-leaf. Move keys and pointers. */
4109 union xfs_btree_key *lkp; /* left btree key */
4110 union xfs_btree_ptr *lpp; /* left address pointer */
4111 union xfs_btree_key *rkp; /* right btree key */
4112 union xfs_btree_ptr *rpp; /* right address pointer */
4114 lkp = xfs_btree_key_addr(cur, lrecs + 1, left);
4115 lpp = xfs_btree_ptr_addr(cur, lrecs + 1, left);
4116 rkp = xfs_btree_key_addr(cur, 1, right);
4117 rpp = xfs_btree_ptr_addr(cur, 1, right);
4119 for (i = 1; i < rrecs; i++) {
4120 error = xfs_btree_check_ptr(cur, rpp, i, level);
4125 xfs_btree_copy_keys(cur, lkp, rkp, rrecs);
4126 xfs_btree_copy_ptrs(cur, lpp, rpp, rrecs);
4128 xfs_btree_log_keys(cur, lbp, lrecs + 1, lrecs + rrecs);
4129 xfs_btree_log_ptrs(cur, lbp, lrecs + 1, lrecs + rrecs);
4131 /* It's a leaf. Move records. */
4132 union xfs_btree_rec *lrp; /* left record pointer */
4133 union xfs_btree_rec *rrp; /* right record pointer */
4135 lrp = xfs_btree_rec_addr(cur, lrecs + 1, left);
4136 rrp = xfs_btree_rec_addr(cur, 1, right);
4138 xfs_btree_copy_recs(cur, lrp, rrp, rrecs);
4139 xfs_btree_log_recs(cur, lbp, lrecs + 1, lrecs + rrecs);
4142 XFS_BTREE_STATS_INC(cur, join);
4145 * Fix up the number of records and right block pointer in the
4146 * surviving block, and log it.
4148 xfs_btree_set_numrecs(left, lrecs + rrecs);
4149 xfs_btree_get_sibling(cur, right, &cptr, XFS_BB_RIGHTSIB),
4150 xfs_btree_set_sibling(cur, left, &cptr, XFS_BB_RIGHTSIB);
4151 xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS | XFS_BB_RIGHTSIB);
4153 /* If there is a right sibling, point it to the remaining block. */
4154 xfs_btree_get_sibling(cur, left, &cptr, XFS_BB_RIGHTSIB);
4155 if (!xfs_btree_ptr_is_null(cur, &cptr)) {
4156 error = xfs_btree_read_buf_block(cur, &cptr, 0, &rrblock, &rrbp);
4159 xfs_btree_set_sibling(cur, rrblock, &lptr, XFS_BB_LEFTSIB);
4160 xfs_btree_log_block(cur, rrbp, XFS_BB_LEFTSIB);
4163 /* Free the deleted block. */
4164 error = xfs_btree_free_block(cur, rbp);
4169 * If we joined with the left neighbor, set the buffer in the
4170 * cursor to the left block, and fix up the index.
4173 cur->bc_bufs[level] = lbp;
4174 cur->bc_ptrs[level] += lrecs;
4175 cur->bc_ra[level] = 0;
4178 * If we joined with the right neighbor and there's a level above
4179 * us, increment the cursor at that level.
4181 else if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) ||
4182 (level + 1 < cur->bc_nlevels)) {
4183 error = xfs_btree_increment(cur, level + 1, &i);
4189 * Readjust the ptr at this level if it's not a leaf, since it's
4190 * still pointing at the deletion point, which makes the cursor
4191 * inconsistent. If this makes the ptr 0, the caller fixes it up.
4192 * We can't use decrement because it would change the next level up.
4195 cur->bc_ptrs[level]--;
4198 * We combined blocks, so we have to update the parent keys if the
4199 * btree supports overlapped intervals. However, bc_ptrs[level + 1]
4200 * points to the old block so that the caller knows which record to
4201 * delete. Therefore, the caller must be savvy enough to call updkeys
4202 * for us if we return stat == 2. The other exit points from this
4203 * function don't require deletions further up the tree, so they can
4204 * call updkeys directly.
4207 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
4208 /* Return value means the next level up has something to do. */
4213 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
4215 xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
4220 * Delete the record pointed to by cur.
4221 * The cursor refers to the place where the record was (could be inserted)
4222 * when the operation returns.
4226 struct xfs_btree_cur *cur,
4227 int *stat) /* success/failure */
4229 int error; /* error return value */
4232 bool joined = false;
4234 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
4237 * Go up the tree, starting at leaf level.
4239 * If 2 is returned then a join was done; go to the next level.
4240 * Otherwise we are done.
4242 for (level = 0, i = 2; i == 2; level++) {
4243 error = xfs_btree_delrec(cur, level, &i);
4251 * If we combined blocks as part of deleting the record, delrec won't
4252 * have updated the parent high keys so we have to do that here.
4254 if (joined && (cur->bc_flags & XFS_BTREE_OVERLAPPING)) {
4255 error = xfs_btree_updkeys_force(cur, 0);
4261 for (level = 1; level < cur->bc_nlevels; level++) {
4262 if (cur->bc_ptrs[level] == 0) {
4263 error = xfs_btree_decrement(cur, level, &i);
4271 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
4275 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
4280 * Get the data from the pointed-to record.
4284 struct xfs_btree_cur *cur, /* btree cursor */
4285 union xfs_btree_rec **recp, /* output: btree record */
4286 int *stat) /* output: success/failure */
4288 struct xfs_btree_block *block; /* btree block */
4289 struct xfs_buf *bp; /* buffer pointer */
4290 int ptr; /* record number */
4292 int error; /* error return value */
4295 ptr = cur->bc_ptrs[0];
4296 block = xfs_btree_get_block(cur, 0, &bp);
4299 error = xfs_btree_check_block(cur, block, 0, bp);
4305 * Off the right end or left end, return failure.
4307 if (ptr > xfs_btree_get_numrecs(block) || ptr <= 0) {
4313 * Point to the record and extract its data.
4315 *recp = xfs_btree_rec_addr(cur, ptr, block);
4320 /* Visit a block in a btree. */
4322 xfs_btree_visit_block(
4323 struct xfs_btree_cur *cur,
4325 xfs_btree_visit_blocks_fn fn,
4328 struct xfs_btree_block *block;
4330 union xfs_btree_ptr rptr;
4333 /* do right sibling readahead */
4334 xfs_btree_readahead(cur, level, XFS_BTCUR_RIGHTRA);
4335 block = xfs_btree_get_block(cur, level, &bp);
4337 /* process the block */
4338 error = fn(cur, level, data);
4342 /* now read rh sibling block for next iteration */
4343 xfs_btree_get_sibling(cur, block, &rptr, XFS_BB_RIGHTSIB);
4344 if (xfs_btree_ptr_is_null(cur, &rptr))
4347 return xfs_btree_lookup_get_block(cur, level, &rptr, &block);
4351 /* Visit every block in a btree. */
4353 xfs_btree_visit_blocks(
4354 struct xfs_btree_cur *cur,
4355 xfs_btree_visit_blocks_fn fn,
4358 union xfs_btree_ptr lptr;
4360 struct xfs_btree_block *block = NULL;
4363 cur->bc_ops->init_ptr_from_cur(cur, &lptr);
4365 /* for each level */
4366 for (level = cur->bc_nlevels - 1; level >= 0; level--) {
4367 /* grab the left hand block */
4368 error = xfs_btree_lookup_get_block(cur, level, &lptr, &block);
4372 /* readahead the left most block for the next level down */
4374 union xfs_btree_ptr *ptr;
4376 ptr = xfs_btree_ptr_addr(cur, 1, block);
4377 xfs_btree_readahead_ptr(cur, ptr, 1);
4379 /* save for the next iteration of the loop */
4383 /* for each buffer in the level */
4385 error = xfs_btree_visit_block(cur, level, fn, data);
4388 if (error != -ENOENT)
4396 * Change the owner of a btree.
4398 * The mechanism we use here is ordered buffer logging. Because we don't know
4399 * how many buffers were are going to need to modify, we don't really want to
4400 * have to make transaction reservations for the worst case of every buffer in a
4401 * full size btree as that may be more space that we can fit in the log....
4403 * We do the btree walk in the most optimal manner possible - we have sibling
4404 * pointers so we can just walk all the blocks on each level from left to right
4405 * in a single pass, and then move to the next level and do the same. We can
4406 * also do readahead on the sibling pointers to get IO moving more quickly,
4407 * though for slow disks this is unlikely to make much difference to performance
4408 * as the amount of CPU work we have to do before moving to the next block is
4411 * For each btree block that we load, modify the owner appropriately, set the
4412 * buffer as an ordered buffer and log it appropriately. We need to ensure that
4413 * we mark the region we change dirty so that if the buffer is relogged in
4414 * a subsequent transaction the changes we make here as an ordered buffer are
4415 * correctly relogged in that transaction. If we are in recovery context, then
4416 * just queue the modified buffer as delayed write buffer so the transaction
4417 * recovery completion writes the changes to disk.
4419 struct xfs_btree_block_change_owner_info {
4420 __uint64_t new_owner;
4421 struct list_head *buffer_list;
4425 xfs_btree_block_change_owner(
4426 struct xfs_btree_cur *cur,
4430 struct xfs_btree_block_change_owner_info *bbcoi = data;
4431 struct xfs_btree_block *block;
4434 /* modify the owner */
4435 block = xfs_btree_get_block(cur, level, &bp);
4436 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
4437 block->bb_u.l.bb_owner = cpu_to_be64(bbcoi->new_owner);
4439 block->bb_u.s.bb_owner = cpu_to_be32(bbcoi->new_owner);
4442 * If the block is a root block hosted in an inode, we might not have a
4443 * buffer pointer here and we shouldn't attempt to log the change as the
4444 * information is already held in the inode and discarded when the root
4445 * block is formatted into the on-disk inode fork. We still change it,
4446 * though, so everything is consistent in memory.
4450 xfs_trans_ordered_buf(cur->bc_tp, bp);
4451 xfs_btree_log_block(cur, bp, XFS_BB_OWNER);
4453 xfs_buf_delwri_queue(bp, bbcoi->buffer_list);
4456 ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE);
4457 ASSERT(level == cur->bc_nlevels - 1);
4464 xfs_btree_change_owner(
4465 struct xfs_btree_cur *cur,
4466 __uint64_t new_owner,
4467 struct list_head *buffer_list)
4469 struct xfs_btree_block_change_owner_info bbcoi;
4471 bbcoi.new_owner = new_owner;
4472 bbcoi.buffer_list = buffer_list;
4474 return xfs_btree_visit_blocks(cur, xfs_btree_block_change_owner,
4479 * xfs_btree_sblock_v5hdr_verify() -- verify the v5 fields of a short-format
4482 * @bp: buffer containing the btree block
4483 * @max_recs: pointer to the m_*_mxr max records field in the xfs mount
4484 * @pag_max_level: pointer to the per-ag max level field
4487 xfs_btree_sblock_v5hdr_verify(
4490 struct xfs_mount *mp = bp->b_target->bt_mount;
4491 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
4492 struct xfs_perag *pag = bp->b_pag;
4494 if (!xfs_sb_version_hascrc(&mp->m_sb))
4496 if (!uuid_equal(&block->bb_u.s.bb_uuid, &mp->m_sb.sb_meta_uuid))
4498 if (block->bb_u.s.bb_blkno != cpu_to_be64(bp->b_bn))
4500 if (pag && be32_to_cpu(block->bb_u.s.bb_owner) != pag->pag_agno)
4506 * xfs_btree_sblock_verify() -- verify a short-format btree block
4508 * @bp: buffer containing the btree block
4509 * @max_recs: maximum records allowed in this btree node
4512 xfs_btree_sblock_verify(
4514 unsigned int max_recs)
4516 struct xfs_mount *mp = bp->b_target->bt_mount;
4517 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
4519 /* numrecs verification */
4520 if (be16_to_cpu(block->bb_numrecs) > max_recs)
4523 /* sibling pointer verification */
4524 if (!block->bb_u.s.bb_leftsib ||
4525 (be32_to_cpu(block->bb_u.s.bb_leftsib) >= mp->m_sb.sb_agblocks &&
4526 block->bb_u.s.bb_leftsib != cpu_to_be32(NULLAGBLOCK)))
4528 if (!block->bb_u.s.bb_rightsib ||
4529 (be32_to_cpu(block->bb_u.s.bb_rightsib) >= mp->m_sb.sb_agblocks &&
4530 block->bb_u.s.bb_rightsib != cpu_to_be32(NULLAGBLOCK)))
4537 * Calculate the number of btree levels needed to store a given number of
4538 * records in a short-format btree.
4541 xfs_btree_compute_maxlevels(
4542 struct xfs_mount *mp,
4547 unsigned long maxblocks;
4549 maxblocks = (len + limits[0] - 1) / limits[0];
4550 for (level = 1; maxblocks > 1; level++)
4551 maxblocks = (maxblocks + limits[1] - 1) / limits[1];
4556 * Query a regular btree for all records overlapping a given interval.
4557 * Start with a LE lookup of the key of low_rec and return all records
4558 * until we find a record with a key greater than the key of high_rec.
4561 xfs_btree_simple_query_range(
4562 struct xfs_btree_cur *cur,
4563 union xfs_btree_key *low_key,
4564 union xfs_btree_key *high_key,
4565 xfs_btree_query_range_fn fn,
4568 union xfs_btree_rec *recp;
4569 union xfs_btree_key rec_key;
4572 bool firstrec = true;
4575 ASSERT(cur->bc_ops->init_high_key_from_rec);
4576 ASSERT(cur->bc_ops->diff_two_keys);
4579 * Find the leftmost record. The btree cursor must be set
4580 * to the low record used to generate low_key.
4583 error = xfs_btree_lookup(cur, XFS_LOOKUP_LE, &stat);
4587 /* Nothing? See if there's anything to the right. */
4589 error = xfs_btree_increment(cur, 0, &stat);
4595 /* Find the record. */
4596 error = xfs_btree_get_rec(cur, &recp, &stat);
4600 /* Skip if high_key(rec) < low_key. */
4602 cur->bc_ops->init_high_key_from_rec(&rec_key, recp);
4604 diff = cur->bc_ops->diff_two_keys(cur, low_key,
4610 /* Stop if high_key < low_key(rec). */
4611 cur->bc_ops->init_key_from_rec(&rec_key, recp);
4612 diff = cur->bc_ops->diff_two_keys(cur, &rec_key, high_key);
4617 error = fn(cur, recp, priv);
4618 if (error < 0 || error == XFS_BTREE_QUERY_RANGE_ABORT)
4622 /* Move on to the next record. */
4623 error = xfs_btree_increment(cur, 0, &stat);
4633 * Query an overlapped interval btree for all records overlapping a given
4634 * interval. This function roughly follows the algorithm given in
4635 * "Interval Trees" of _Introduction to Algorithms_, which is section
4636 * 14.3 in the 2nd and 3rd editions.
4638 * First, generate keys for the low and high records passed in.
4640 * For any leaf node, generate the high and low keys for the record.
4641 * If the record keys overlap with the query low/high keys, pass the
4642 * record to the function iterator.
4644 * For any internal node, compare the low and high keys of each
4645 * pointer against the query low/high keys. If there's an overlap,
4646 * follow the pointer.
4648 * As an optimization, we stop scanning a block when we find a low key
4649 * that is greater than the query's high key.
4652 xfs_btree_overlapped_query_range(
4653 struct xfs_btree_cur *cur,
4654 union xfs_btree_key *low_key,
4655 union xfs_btree_key *high_key,
4656 xfs_btree_query_range_fn fn,
4659 union xfs_btree_ptr ptr;
4660 union xfs_btree_ptr *pp;
4661 union xfs_btree_key rec_key;
4662 union xfs_btree_key rec_hkey;
4663 union xfs_btree_key *lkp;
4664 union xfs_btree_key *hkp;
4665 union xfs_btree_rec *recp;
4666 struct xfs_btree_block *block;
4674 /* Load the root of the btree. */
4675 level = cur->bc_nlevels - 1;
4676 cur->bc_ops->init_ptr_from_cur(cur, &ptr);
4677 error = xfs_btree_lookup_get_block(cur, level, &ptr, &block);
4680 xfs_btree_get_block(cur, level, &bp);
4681 trace_xfs_btree_overlapped_query_range(cur, level, bp);
4683 error = xfs_btree_check_block(cur, block, level, bp);
4687 cur->bc_ptrs[level] = 1;
4689 while (level < cur->bc_nlevels) {
4690 block = xfs_btree_get_block(cur, level, &bp);
4692 /* End of node, pop back towards the root. */
4693 if (cur->bc_ptrs[level] > be16_to_cpu(block->bb_numrecs)) {
4695 if (level < cur->bc_nlevels - 1)
4696 cur->bc_ptrs[level + 1]++;
4702 /* Handle a leaf node. */
4703 recp = xfs_btree_rec_addr(cur, cur->bc_ptrs[0], block);
4705 cur->bc_ops->init_high_key_from_rec(&rec_hkey, recp);
4706 ldiff = cur->bc_ops->diff_two_keys(cur, &rec_hkey,
4709 cur->bc_ops->init_key_from_rec(&rec_key, recp);
4710 hdiff = cur->bc_ops->diff_two_keys(cur, high_key,
4714 * If (record's high key >= query's low key) and
4715 * (query's high key >= record's low key), then
4716 * this record overlaps the query range; callback.
4718 if (ldiff >= 0 && hdiff >= 0) {
4719 error = fn(cur, recp, priv);
4721 error == XFS_BTREE_QUERY_RANGE_ABORT)
4723 } else if (hdiff < 0) {
4724 /* Record is larger than high key; pop. */
4727 cur->bc_ptrs[level]++;
4731 /* Handle an internal node. */
4732 lkp = xfs_btree_key_addr(cur, cur->bc_ptrs[level], block);
4733 hkp = xfs_btree_high_key_addr(cur, cur->bc_ptrs[level], block);
4734 pp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[level], block);
4736 ldiff = cur->bc_ops->diff_two_keys(cur, hkp, low_key);
4737 hdiff = cur->bc_ops->diff_two_keys(cur, high_key, lkp);
4740 * If (pointer's high key >= query's low key) and
4741 * (query's high key >= pointer's low key), then
4742 * this record overlaps the query range; follow pointer.
4744 if (ldiff >= 0 && hdiff >= 0) {
4746 error = xfs_btree_lookup_get_block(cur, level, pp,
4750 xfs_btree_get_block(cur, level, &bp);
4751 trace_xfs_btree_overlapped_query_range(cur, level, bp);
4753 error = xfs_btree_check_block(cur, block, level, bp);
4757 cur->bc_ptrs[level] = 1;
4759 } else if (hdiff < 0) {
4760 /* The low key is larger than the upper range; pop. */
4763 cur->bc_ptrs[level]++;
4768 * If we don't end this function with the cursor pointing at a record
4769 * block, a subsequent non-error cursor deletion will not release
4770 * node-level buffers, causing a buffer leak. This is quite possible
4771 * with a zero-results range query, so release the buffers if we
4772 * failed to return any results.
4774 if (cur->bc_bufs[0] == NULL) {
4775 for (i = 0; i < cur->bc_nlevels; i++) {
4776 if (cur->bc_bufs[i]) {
4777 xfs_trans_brelse(cur->bc_tp, cur->bc_bufs[i]);
4778 cur->bc_bufs[i] = NULL;
4779 cur->bc_ptrs[i] = 0;
4789 * Query a btree for all records overlapping a given interval of keys. The
4790 * supplied function will be called with each record found; return one of the
4791 * XFS_BTREE_QUERY_RANGE_{CONTINUE,ABORT} values or the usual negative error
4792 * code. This function returns XFS_BTREE_QUERY_RANGE_ABORT, zero, or a
4793 * negative error code.
4796 xfs_btree_query_range(
4797 struct xfs_btree_cur *cur,
4798 union xfs_btree_irec *low_rec,
4799 union xfs_btree_irec *high_rec,
4800 xfs_btree_query_range_fn fn,
4803 union xfs_btree_rec rec;
4804 union xfs_btree_key low_key;
4805 union xfs_btree_key high_key;
4807 /* Find the keys of both ends of the interval. */
4808 cur->bc_rec = *high_rec;
4809 cur->bc_ops->init_rec_from_cur(cur, &rec);
4810 cur->bc_ops->init_key_from_rec(&high_key, &rec);
4812 cur->bc_rec = *low_rec;
4813 cur->bc_ops->init_rec_from_cur(cur, &rec);
4814 cur->bc_ops->init_key_from_rec(&low_key, &rec);
4816 /* Enforce low key < high key. */
4817 if (cur->bc_ops->diff_two_keys(cur, &low_key, &high_key) > 0)
4820 if (!(cur->bc_flags & XFS_BTREE_OVERLAPPING))
4821 return xfs_btree_simple_query_range(cur, &low_key,
4822 &high_key, fn, priv);
4823 return xfs_btree_overlapped_query_range(cur, &low_key, &high_key,
4828 * Calculate the number of blocks needed to store a given number of records
4829 * in a short-format (per-AG metadata) btree.
4832 xfs_btree_calc_size(
4833 struct xfs_mount *mp,
4835 unsigned long long len)
4841 maxrecs = limits[0];
4842 for (level = 0, rval = 0; len > 1; level++) {
4844 do_div(len, maxrecs);
4845 maxrecs = limits[1];
4852 xfs_btree_count_blocks_helper(
4853 struct xfs_btree_cur *cur,
4857 xfs_extlen_t *blocks = data;
4863 /* Count the blocks in a btree and return the result in *blocks. */
4865 xfs_btree_count_blocks(
4866 struct xfs_btree_cur *cur,
4867 xfs_extlen_t *blocks)
4870 return xfs_btree_visit_blocks(cur, xfs_btree_count_blocks_helper,