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xfs: Use defines for CRC offsets in all cases
[deliverable/linux.git] / fs / xfs / xfs_btree.c
CommitLineData
1da177e4 1/*
7b718769
NS		 2 * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
1da177e4 4 *
7b718769
NS		 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
1da177e4
LT		 7 * published by the Free Software Foundation.
8 *
7b718769
NS		 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.
1da177e4 13 *
7b718769
NS		 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
1da177e4 17 */
1da177e4 18#include "xfs.h"
a844f451 19#include "xfs_fs.h"
70a9883c 20#include "xfs_shared.h"
a4fbe6ab 21#include "xfs_format.h"
239880ef
DC		 22#include "xfs_log_format.h"
23#include "xfs_trans_resv.h"
a844f451 24#include "xfs_bit.h"
1da177e4
LT		 25#include "xfs_sb.h"
26#include "xfs_ag.h"
1da177e4 27#include "xfs_mount.h"
1da177e4 28#include "xfs_inode.h"
239880ef 29#include "xfs_trans.h"
38bb7423 30#include "xfs_inode_item.h"
ee1a47ab 31#include "xfs_buf_item.h"
a844f451 32#include "xfs_btree.h"
1da177e4 33#include "xfs_error.h"
0b1b213f 34#include "xfs_trace.h"
ee1a47ab 35#include "xfs_cksum.h"
1da177e4
LT		 36
37/*
38 * Cursor allocation zone.
39 */
40kmem_zone_t *xfs_btree_cur_zone;
41
42/*
43 * Btree magic numbers.
44 */
ee1a47ab
CH		 45static const __uint32_t xfs_magics[2][XFS_BTNUM_MAX] = {
46 { XFS_ABTB_MAGIC, XFS_ABTC_MAGIC, XFS_BMAP_MAGIC, XFS_IBT_MAGIC },
47 { XFS_ABTB_CRC_MAGIC, XFS_ABTC_CRC_MAGIC,
48 XFS_BMAP_CRC_MAGIC, XFS_IBT_CRC_MAGIC }
1da177e4 49};
ee1a47ab
CH		 50#define xfs_btree_magic(cur) \
51 xfs_magics[!!((cur)->bc_flags & XFS_BTREE_CRC_BLOCKS)][cur->bc_btnum]
1da177e4 52
1da177e4 53
7cc95a82 54STATIC int /* error (0 or EFSCORRUPTED) */
a23f6ef8
CH		 55xfs_btree_check_lblock(
56 struct xfs_btree_cur *cur, /* btree cursor */
7cc95a82 57 struct xfs_btree_block *block, /* btree long form block pointer */
a23f6ef8
CH		 58 int level, /* level of the btree block */
59 struct xfs_buf *bp) /* buffer for block, if any */
60{
ee1a47ab 61 int lblock_ok = 1; /* block passes checks */
a23f6ef8
CH		 62 struct xfs_mount *mp; /* file system mount point */
63
64 mp = cur->bc_mp;
ee1a47ab
CH		 65
66 if (xfs_sb_version_hascrc(&mp->m_sb)) {
67 lblock_ok = lblock_ok &&
68 uuid_equal(&block->bb_u.l.bb_uuid, &mp->m_sb.sb_uuid) &&
69 block->bb_u.l.bb_blkno == cpu_to_be64(
70 bp ? bp->b_bn : XFS_BUF_DADDR_NULL);
71 }
72
73 lblock_ok = lblock_ok &&
74 be32_to_cpu(block->bb_magic) == xfs_btree_magic(cur) &&
a23f6ef8
CH		 75 be16_to_cpu(block->bb_level) == level &&
76 be16_to_cpu(block->bb_numrecs) <=
ce5e42db 77 cur->bc_ops->get_maxrecs(cur, level) &&
7cc95a82 78 block->bb_u.l.bb_leftsib &&
69ef921b 79 (block->bb_u.l.bb_leftsib == cpu_to_be64(NULLDFSBNO) ||
7cc95a82 80 XFS_FSB_SANITY_CHECK(mp,
ee1a47ab 81 be64_to_cpu(block->bb_u.l.bb_leftsib))) &&
7cc95a82 82 block->bb_u.l.bb_rightsib &&
69ef921b 83 (block->bb_u.l.bb_rightsib == cpu_to_be64(NULLDFSBNO) ||
7cc95a82 84 XFS_FSB_SANITY_CHECK(mp,
ee1a47ab
CH		 85 be64_to_cpu(block->bb_u.l.bb_rightsib)));
86
a23f6ef8
CH		 87 if (unlikely(XFS_TEST_ERROR(!lblock_ok, mp,
88 XFS_ERRTAG_BTREE_CHECK_LBLOCK,
89 XFS_RANDOM_BTREE_CHECK_LBLOCK))) {
90 if (bp)
0b1b213f 91 trace_xfs_btree_corrupt(bp, _RET_IP_);
ee1a47ab 92 XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, mp);
a23f6ef8
CH		 93 return XFS_ERROR(EFSCORRUPTED);
94 }
95 return 0;
96}
97
3cc7524c 98STATIC int /* error (0 or EFSCORRUPTED) */
1da177e4 99xfs_btree_check_sblock(
a23f6ef8 100 struct xfs_btree_cur *cur, /* btree cursor */
7cc95a82 101 struct xfs_btree_block *block, /* btree short form block pointer */
1da177e4 102 int level, /* level of the btree block */
a23f6ef8 103 struct xfs_buf *bp) /* buffer containing block */
1da177e4 104{
ee1a47ab 105 struct xfs_mount *mp; /* file system mount point */
a23f6ef8
CH		 106 struct xfs_buf *agbp; /* buffer for ag. freespace struct */
107 struct xfs_agf *agf; /* ag. freespace structure */
1da177e4 108 xfs_agblock_t agflen; /* native ag. freespace length */
ee1a47ab 109 int sblock_ok = 1; /* block passes checks */
1da177e4 110
ee1a47ab 111 mp = cur->bc_mp;
1da177e4
LT		 112 agbp = cur->bc_private.a.agbp;
113 agf = XFS_BUF_TO_AGF(agbp);
16259e7d 114 agflen = be32_to_cpu(agf->agf_length);
ee1a47ab
CH		 115
116 if (xfs_sb_version_hascrc(&mp->m_sb)) {
117 sblock_ok = sblock_ok &&
118 uuid_equal(&block->bb_u.s.bb_uuid, &mp->m_sb.sb_uuid) &&
119 block->bb_u.s.bb_blkno == cpu_to_be64(
120 bp ? bp->b_bn : XFS_BUF_DADDR_NULL);
121 }
122
123 sblock_ok = sblock_ok &&
124 be32_to_cpu(block->bb_magic) == xfs_btree_magic(cur) &&
16259e7d
CH		 125 be16_to_cpu(block->bb_level) == level &&
126 be16_to_cpu(block->bb_numrecs) <=
ce5e42db 127 cur->bc_ops->get_maxrecs(cur, level) &&
69ef921b 128 (block->bb_u.s.bb_leftsib == cpu_to_be32(NULLAGBLOCK) ||
7cc95a82
CH		 129 be32_to_cpu(block->bb_u.s.bb_leftsib) < agflen) &&
130 block->bb_u.s.bb_leftsib &&
69ef921b 131 (block->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK) ||
7cc95a82
CH		 132 be32_to_cpu(block->bb_u.s.bb_rightsib) < agflen) &&
133 block->bb_u.s.bb_rightsib;
ee1a47ab
CH		 134
135 if (unlikely(XFS_TEST_ERROR(!sblock_ok, mp,
1da177e4
LT		 136 XFS_ERRTAG_BTREE_CHECK_SBLOCK,
137 XFS_RANDOM_BTREE_CHECK_SBLOCK))) {
138 if (bp)
0b1b213f 139 trace_xfs_btree_corrupt(bp, _RET_IP_);
ee1a47ab 140 XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, mp);
1da177e4
LT		 141 return XFS_ERROR(EFSCORRUPTED);
142 }
143 return 0;
144}
145
146/*
a23f6ef8
CH		 147 * Debug routine: check that block header is ok.
148 */
149int
150xfs_btree_check_block(
151 struct xfs_btree_cur *cur, /* btree cursor */
152 struct xfs_btree_block *block, /* generic btree block pointer */
153 int level, /* level of the btree block */
154 struct xfs_buf *bp) /* buffer containing block, if any */
155{
7cc95a82
CH		 156 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
157 return xfs_btree_check_lblock(cur, block, level, bp);
158 else
159 return xfs_btree_check_sblock(cur, block, level, bp);
a23f6ef8
CH		 160}
161
162/*
163 * Check that (long) pointer is ok.
164 */
165int /* error (0 or EFSCORRUPTED) */
166xfs_btree_check_lptr(
167 struct xfs_btree_cur *cur, /* btree cursor */
168 xfs_dfsbno_t bno, /* btree block disk address */
169 int level) /* btree block level */
170{
171 XFS_WANT_CORRUPTED_RETURN(
172 level > 0 &&
173 bno != NULLDFSBNO &&
174 XFS_FSB_SANITY_CHECK(cur->bc_mp, bno));
175 return 0;
176}
177
24ee0e49 178#ifdef DEBUG
a23f6ef8
CH		 179/*
180 * Check that (short) pointer is ok.
1da177e4 181 */
3cc7524c 182STATIC int /* error (0 or EFSCORRUPTED) */
1da177e4 183xfs_btree_check_sptr(
a23f6ef8
CH		 184 struct xfs_btree_cur *cur, /* btree cursor */
185 xfs_agblock_t bno, /* btree block disk address */
186 int level) /* btree block level */
1da177e4 187{
a23f6ef8 188 xfs_agblock_t agblocks = cur->bc_mp->m_sb.sb_agblocks;
1da177e4 189
1da177e4
LT		 190 XFS_WANT_CORRUPTED_RETURN(
191 level > 0 &&
a23f6ef8
CH		 192 bno != NULLAGBLOCK &&
193 bno != 0 &&
194 bno < agblocks);
1da177e4
LT		 195 return 0;
196}
197
a23f6ef8
CH		 198/*
199 * Check that block ptr is ok.
200 */
3cc7524c 201STATIC int /* error (0 or EFSCORRUPTED) */
a23f6ef8
CH		 202xfs_btree_check_ptr(
203 struct xfs_btree_cur *cur, /* btree cursor */
204 union xfs_btree_ptr *ptr, /* btree block disk address */
205 int index, /* offset from ptr to check */
206 int level) /* btree block level */
207{
208 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
209 return xfs_btree_check_lptr(cur,
210 be64_to_cpu((&ptr->l)[index]), level);
211 } else {
212 return xfs_btree_check_sptr(cur,
213 be32_to_cpu((&ptr->s)[index]), level);
214 }
215}
24ee0e49 216#endif
a23f6ef8 217
ee1a47ab
CH		 218/*
219 * Calculate CRC on the whole btree block and stuff it into the
220 * long-form btree header.
221 *
222 * Prior to calculting the CRC, pull the LSN out of the buffer log item and put
223 * it into the buffer so recovery knows what the last modifcation was that made
224 * it to disk.
225 */
226void
227xfs_btree_lblock_calc_crc(
228 struct xfs_buf *bp)
229{
230 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
231 struct xfs_buf_log_item *bip = bp->b_fspriv;
232
233 if (!xfs_sb_version_hascrc(&bp->b_target->bt_mount->m_sb))
234 return;
235 if (bip)
236 block->bb_u.l.bb_lsn = cpu_to_be64(bip->bli_item.li_lsn);
237 xfs_update_cksum(bp->b_addr, BBTOB(bp->b_length),
238 XFS_BTREE_LBLOCK_CRC_OFF);
239}
240
241bool
242xfs_btree_lblock_verify_crc(
243 struct xfs_buf *bp)
244{
245 if (xfs_sb_version_hascrc(&bp->b_target->bt_mount->m_sb))
246 return xfs_verify_cksum(bp->b_addr, BBTOB(bp->b_length),
247 XFS_BTREE_LBLOCK_CRC_OFF);
248 return true;
249}
250
251/*
252 * Calculate CRC on the whole btree block and stuff it into the
253 * short-form btree header.
254 *
255 * Prior to calculting the CRC, pull the LSN out of the buffer log item and put
256 * it into the buffer so recovery knows what the last modifcation was that made
257 * it to disk.
258 */
259void
260xfs_btree_sblock_calc_crc(
261 struct xfs_buf *bp)
262{
263 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
264 struct xfs_buf_log_item *bip = bp->b_fspriv;
265
266 if (!xfs_sb_version_hascrc(&bp->b_target->bt_mount->m_sb))
267 return;
268 if (bip)
269 block->bb_u.s.bb_lsn = cpu_to_be64(bip->bli_item.li_lsn);
270 xfs_update_cksum(bp->b_addr, BBTOB(bp->b_length),
271 XFS_BTREE_SBLOCK_CRC_OFF);
272}
273
274bool
275xfs_btree_sblock_verify_crc(
276 struct xfs_buf *bp)
277{
278 if (xfs_sb_version_hascrc(&bp->b_target->bt_mount->m_sb))
279 return xfs_verify_cksum(bp->b_addr, BBTOB(bp->b_length),
280 XFS_BTREE_SBLOCK_CRC_OFF);
281 return true;
282}
283
1da177e4
LT		 284/*
285 * Delete the btree cursor.
286 */
287void
288xfs_btree_del_cursor(
289 xfs_btree_cur_t *cur, /* btree cursor */
290 int error) /* del because of error */
291{
292 int i; /* btree level */
293
294 /*
295 * Clear the buffer pointers, and release the buffers.
296 * If we're doing this in the face of an error, we
297 * need to make sure to inspect all of the entries
298 * in the bc_bufs array for buffers to be unlocked.
299 * This is because some of the btree code works from
300 * level n down to 0, and if we get an error along
301 * the way we won't have initialized all the entries
302 * down to 0.
303 */
304 for (i = 0; i < cur->bc_nlevels; i++) {
305 if (cur->bc_bufs[i])
c0e59e1a 306 xfs_trans_brelse(cur->bc_tp, cur->bc_bufs[i]);
1da177e4
LT		 307 else if (!error)
308 break;
309 }
310 /*
311 * Can't free a bmap cursor without having dealt with the
312 * allocated indirect blocks' accounting.
313 */
314 ASSERT(cur->bc_btnum != XFS_BTNUM_BMAP ||
315 cur->bc_private.b.allocated == 0);
316 /*
317 * Free the cursor.
318 */
319 kmem_zone_free(xfs_btree_cur_zone, cur);
320}
321
322/*
323 * Duplicate the btree cursor.
324 * Allocate a new one, copy the record, re-get the buffers.
325 */
326int /* error */
327xfs_btree_dup_cursor(
328 xfs_btree_cur_t *cur, /* input cursor */
329 xfs_btree_cur_t **ncur) /* output cursor */
330{
331 xfs_buf_t *bp; /* btree block's buffer pointer */
332 int error; /* error return value */
333 int i; /* level number of btree block */
334 xfs_mount_t *mp; /* mount structure for filesystem */
335 xfs_btree_cur_t *new; /* new cursor value */
336 xfs_trans_t *tp; /* transaction pointer, can be NULL */
337
338 tp = cur->bc_tp;
339 mp = cur->bc_mp;
561f7d17 340
1da177e4
LT		 341 /*
342 * Allocate a new cursor like the old one.
343 */
561f7d17
CH		 344 new = cur->bc_ops->dup_cursor(cur);
345
1da177e4
LT		 346 /*
347 * Copy the record currently in the cursor.
348 */
349 new->bc_rec = cur->bc_rec;
561f7d17 350
1da177e4
LT		 351 /*
352 * For each level current, re-get the buffer and copy the ptr value.
353 */
354 for (i = 0; i < new->bc_nlevels; i++) {
355 new->bc_ptrs[i] = cur->bc_ptrs[i];
356 new->bc_ra[i] = cur->bc_ra[i];
c3f8fc73
DC		 357 bp = cur->bc_bufs[i];
358 if (bp) {
359 error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
360 XFS_BUF_ADDR(bp), mp->m_bsize,
3d3e6f64 361 0, &bp,
1813dd64 362 cur->bc_ops->buf_ops);
c3f8fc73 363 if (error) {
1da177e4
LT		 364 xfs_btree_del_cursor(new, error);
365 *ncur = NULL;
366 return error;
367 }
ee1a47ab
CH		 368 }
369 new->bc_bufs[i] = bp;
1da177e4 370 }
1da177e4
LT		 371 *ncur = new;
372 return 0;
373}
374
65f1eaea
CH		 375/*
376 * XFS btree block layout and addressing:
377 *
378 * There are two types of blocks in the btree: leaf and non-leaf blocks.
379 *
380 * The leaf record start with a header then followed by records containing
381 * the values. A non-leaf block also starts with the same header, and
382 * then first contains lookup keys followed by an equal number of pointers
383 * to the btree blocks at the previous level.
384 *
385 * +--------+-------+-------+-------+-------+-------+-------+
386 * Leaf: | header | rec 1 | rec 2 | rec 3 | rec 4 | rec 5 | rec N |
387 * +--------+-------+-------+-------+-------+-------+-------+
388 *
389 * +--------+-------+-------+-------+-------+-------+-------+
390 * Non-Leaf: | header | key 1 | key 2 | key N | ptr 1 | ptr 2 | ptr N |
391 * +--------+-------+-------+-------+-------+-------+-------+
392 *
393 * The header is called struct xfs_btree_block for reasons better left unknown
394 * and comes in different versions for short (32bit) and long (64bit) block
395 * pointers. The record and key structures are defined by the btree instances
396 * and opaque to the btree core. The block pointers are simple disk endian
397 * integers, available in a short (32bit) and long (64bit) variant.
398 *
399 * The helpers below calculate the offset of a given record, key or pointer
400 * into a btree block (xfs_btree_*_offset) or return a pointer to the given
401 * record, key or pointer (xfs_btree_*_addr). Note that all addressing
402 * inside the btree block is done using indices starting at one, not zero!
403 */
404
405/*
406 * Return size of the btree block header for this btree instance.
407 */
408static inline size_t xfs_btree_block_len(struct xfs_btree_cur *cur)
409{
ee1a47ab
CH		 410 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
411 if (cur->bc_flags & XFS_BTREE_CRC_BLOCKS)
412 return XFS_BTREE_LBLOCK_CRC_LEN;
413 return XFS_BTREE_LBLOCK_LEN;
414 }
415 if (cur->bc_flags & XFS_BTREE_CRC_BLOCKS)
416 return XFS_BTREE_SBLOCK_CRC_LEN;
417 return XFS_BTREE_SBLOCK_LEN;
65f1eaea
CH		 418}
419
420/*
421 * Return size of btree block pointers for this btree instance.
422 */
423static inline size_t xfs_btree_ptr_len(struct xfs_btree_cur *cur)
424{
425 return (cur->bc_flags & XFS_BTREE_LONG_PTRS) ?
426 sizeof(__be64) : sizeof(__be32);
427}
428
429/*
430 * Calculate offset of the n-th record in a btree block.
431 */
432STATIC size_t
433xfs_btree_rec_offset(
434 struct xfs_btree_cur *cur,
435 int n)
436{
437 return xfs_btree_block_len(cur) +
438 (n - 1) * cur->bc_ops->rec_len;
439}
440
441/*
442 * Calculate offset of the n-th key in a btree block.
443 */
444STATIC size_t
445xfs_btree_key_offset(
446 struct xfs_btree_cur *cur,
447 int n)
448{
449 return xfs_btree_block_len(cur) +
450 (n - 1) * cur->bc_ops->key_len;
451}
452
453/*
454 * Calculate offset of the n-th block pointer in a btree block.
455 */
456STATIC size_t
457xfs_btree_ptr_offset(
458 struct xfs_btree_cur *cur,
459 int n,
460 int level)
461{
462 return xfs_btree_block_len(cur) +
463 cur->bc_ops->get_maxrecs(cur, level) * cur->bc_ops->key_len +
464 (n - 1) * xfs_btree_ptr_len(cur);
465}
466
467/*
468 * Return a pointer to the n-th record in the btree block.
469 */
470STATIC union xfs_btree_rec *
471xfs_btree_rec_addr(
472 struct xfs_btree_cur *cur,
473 int n,
474 struct xfs_btree_block *block)
475{
476 return (union xfs_btree_rec *)
477 ((char *)block + xfs_btree_rec_offset(cur, n));
478}
479
480/*
481 * Return a pointer to the n-th key in the btree block.
482 */
483STATIC union xfs_btree_key *
484xfs_btree_key_addr(
485 struct xfs_btree_cur *cur,
486 int n,
487 struct xfs_btree_block *block)
488{
489 return (union xfs_btree_key *)
490 ((char *)block + xfs_btree_key_offset(cur, n));
491}
492
493/*
494 * Return a pointer to the n-th block pointer in the btree block.
495 */
496STATIC union xfs_btree_ptr *
497xfs_btree_ptr_addr(
498 struct xfs_btree_cur *cur,
499 int n,
500 struct xfs_btree_block *block)
501{
502 int level = xfs_btree_get_level(block);
503
504 ASSERT(block->bb_level != 0);
505
506 return (union xfs_btree_ptr *)
507 ((char *)block + xfs_btree_ptr_offset(cur, n, level));
508}
509
8186e517 510/*
1cb93863 511 * Get the root block which is stored in the inode.
8186e517
CH		 512 *
513 * For now this btree implementation assumes the btree root is always
514 * stored in the if_broot field of an inode fork.
515 */
516STATIC struct xfs_btree_block *
517xfs_btree_get_iroot(
518 struct xfs_btree_cur *cur)
519{
520 struct xfs_ifork *ifp;
521
522 ifp = XFS_IFORK_PTR(cur->bc_private.b.ip, cur->bc_private.b.whichfork);
523 return (struct xfs_btree_block *)ifp->if_broot;
524}
525
1da177e4
LT		 526/*
527 * Retrieve the block pointer from the cursor at the given level.
8186e517 528 * This may be an inode btree root or from a buffer.
1da177e4 529 */
8186e517 530STATIC struct xfs_btree_block * /* generic btree block pointer */
1da177e4 531xfs_btree_get_block(
8186e517 532 struct xfs_btree_cur *cur, /* btree cursor */
1da177e4 533 int level, /* level in btree */
8186e517 534 struct xfs_buf **bpp) /* buffer containing the block */
1da177e4 535{
8186e517
CH		 536 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
537 (level == cur->bc_nlevels - 1)) {
538 *bpp = NULL;
539 return xfs_btree_get_iroot(cur);
1da177e4 540 }
8186e517
CH		 541
542 *bpp = cur->bc_bufs[level];
543 return XFS_BUF_TO_BLOCK(*bpp);
1da177e4
LT		 544}
545
546/*
547 * Get a buffer for the block, return it with no data read.
548 * Long-form addressing.
549 */
550xfs_buf_t * /* buffer for fsbno */
551xfs_btree_get_bufl(
552 xfs_mount_t *mp, /* file system mount point */
553 xfs_trans_t *tp, /* transaction pointer */
554 xfs_fsblock_t fsbno, /* file system block number */
555 uint lock) /* lock flags for get_buf */
556{
557 xfs_buf_t *bp; /* buffer pointer (return value) */
558 xfs_daddr_t d; /* real disk block address */
559
560 ASSERT(fsbno != NULLFSBLOCK);
561 d = XFS_FSB_TO_DADDR(mp, fsbno);
562 bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, d, mp->m_bsize, lock);
5a52c2a5 563 ASSERT(!xfs_buf_geterror(bp));
1da177e4
LT		 564 return bp;
565}
566
567/*
568 * Get a buffer for the block, return it with no data read.
569 * Short-form addressing.
570 */
571xfs_buf_t * /* buffer for agno/agbno */
572xfs_btree_get_bufs(
573 xfs_mount_t *mp, /* file system mount point */
574 xfs_trans_t *tp, /* transaction pointer */
575 xfs_agnumber_t agno, /* allocation group number */
576 xfs_agblock_t agbno, /* allocation group block number */
577 uint lock) /* lock flags for get_buf */
578{
579 xfs_buf_t *bp; /* buffer pointer (return value) */
580 xfs_daddr_t d; /* real disk block address */
581
582 ASSERT(agno != NULLAGNUMBER);
583 ASSERT(agbno != NULLAGBLOCK);
584 d = XFS_AGB_TO_DADDR(mp, agno, agbno);
585 bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, d, mp->m_bsize, lock);
5a52c2a5 586 ASSERT(!xfs_buf_geterror(bp));
1da177e4
LT		 587 return bp;
588}
589
1da177e4
LT		 590/*
591 * Check for the cursor referring to the last block at the given level.
592 */
593int /* 1=is last block, 0=not last block */
594xfs_btree_islastblock(
595 xfs_btree_cur_t *cur, /* btree cursor */
596 int level) /* level to check */
597{
7cc95a82 598 struct xfs_btree_block *block; /* generic btree block pointer */
1da177e4
LT		 599 xfs_buf_t *bp; /* buffer containing block */
600
601 block = xfs_btree_get_block(cur, level, &bp);
602 xfs_btree_check_block(cur, block, level, bp);
e99ab90d 603 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
69ef921b 604 return block->bb_u.l.bb_rightsib == cpu_to_be64(NULLDFSBNO);
1da177e4 605 else
69ef921b 606 return block->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK);
1da177e4
LT		 607}
608
cdcf4333
CH		 609/*
610 * Change the cursor to point to the first record at the given level.
611 * Other levels are unaffected.
612 */
3cc7524c 613STATIC int /* success=1, failure=0 */
cdcf4333
CH		 614xfs_btree_firstrec(
615 xfs_btree_cur_t *cur, /* btree cursor */
616 int level) /* level to change */
617{
7cc95a82 618 struct xfs_btree_block *block; /* generic btree block pointer */
cdcf4333
CH		 619 xfs_buf_t *bp; /* buffer containing block */
620
621 /*
622 * Get the block pointer for this level.
623 */
624 block = xfs_btree_get_block(cur, level, &bp);
625 xfs_btree_check_block(cur, block, level, bp);
626 /*
627 * It's empty, there is no such record.
628 */
f2277f06 629 if (!block->bb_numrecs)
cdcf4333
CH		 630 return 0;
631 /*
632 * Set the ptr value to 1, that's the first record/key.
633 */
634 cur->bc_ptrs[level] = 1;
635 return 1;
636}
637
1da177e4
LT		 638/*
639 * Change the cursor to point to the last record in the current block
640 * at the given level. Other levels are unaffected.
641 */
3cc7524c 642STATIC int /* success=1, failure=0 */
1da177e4
LT		 643xfs_btree_lastrec(
644 xfs_btree_cur_t *cur, /* btree cursor */
645 int level) /* level to change */
646{
7cc95a82 647 struct xfs_btree_block *block; /* generic btree block pointer */
1da177e4
LT		 648 xfs_buf_t *bp; /* buffer containing block */
649
650 /*
651 * Get the block pointer for this level.
652 */
653 block = xfs_btree_get_block(cur, level, &bp);
654 xfs_btree_check_block(cur, block, level, bp);
655 /*
656 * It's empty, there is no such record.
657 */
f2277f06 658 if (!block->bb_numrecs)
1da177e4
LT		 659 return 0;
660 /*
661 * Set the ptr value to numrecs, that's the last record/key.
662 */
f2277f06 663 cur->bc_ptrs[level] = be16_to_cpu(block->bb_numrecs);
1da177e4
LT		 664 return 1;
665}
666
667/*
668 * Compute first and last byte offsets for the fields given.
669 * Interprets the offsets table, which contains struct field offsets.
670 */
671void
672xfs_btree_offsets(
673 __int64_t fields, /* bitmask of fields */
674 const short *offsets, /* table of field offsets */
675 int nbits, /* number of bits to inspect */
676 int *first, /* output: first byte offset */
677 int *last) /* output: last byte offset */
678{
679 int i; /* current bit number */
680 __int64_t imask; /* mask for current bit number */
681
682 ASSERT(fields != 0);
683 /*
684 * Find the lowest bit, so the first byte offset.
685 */
686 for (i = 0, imask = 1LL; ; i++, imask <<= 1) {
687 if (imask & fields) {
688 *first = offsets[i];
689 break;
690 }
691 }
692 /*
693 * Find the highest bit, so the last byte offset.
694 */
695 for (i = nbits - 1, imask = 1LL << i; ; i--, imask >>= 1) {
696 if (imask & fields) {
697 *last = offsets[i + 1] - 1;
698 break;
699 }
700 }
701}
702
703/*
704 * Get a buffer for the block, return it read in.
705 * Long-form addressing.
706 */
3d3e6f64 707int
1da177e4 708xfs_btree_read_bufl(
3d3e6f64
DC		 709 struct xfs_mount *mp, /* file system mount point */
710 struct xfs_trans *tp, /* transaction pointer */
711 xfs_fsblock_t fsbno, /* file system block number */
712 uint lock, /* lock flags for read_buf */
713 struct xfs_buf **bpp, /* buffer for fsbno */
714 int refval, /* ref count value for buffer */
1813dd64 715 const struct xfs_buf_ops *ops)
1da177e4 716{
3d3e6f64 717 struct xfs_buf *bp; /* return value */
1da177e4 718 xfs_daddr_t d; /* real disk block address */
3d3e6f64 719 int error;
1da177e4
LT		 720
721 ASSERT(fsbno != NULLFSBLOCK);
722 d = XFS_FSB_TO_DADDR(mp, fsbno);
c3f8fc73 723 error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, d,
1813dd64 724 mp->m_bsize, lock, &bp, ops);
c3f8fc73 725 if (error)
1da177e4 726 return error;
5a52c2a5 727 ASSERT(!xfs_buf_geterror(bp));
821eb21d 728 if (bp)
38f23232 729 xfs_buf_set_ref(bp, refval);
1da177e4
LT		 730 *bpp = bp;
731 return 0;
732}
733
1da177e4
LT		 734/*
735 * Read-ahead the block, don't wait for it, don't return a buffer.
736 * Long-form addressing.
737 */
738/* ARGSUSED */
739void
740xfs_btree_reada_bufl(
3d3e6f64
DC		 741 struct xfs_mount *mp, /* file system mount point */
742 xfs_fsblock_t fsbno, /* file system block number */
743 xfs_extlen_t count, /* count of filesystem blocks */
1813dd64 744 const struct xfs_buf_ops *ops)
1da177e4
LT		 745{
746 xfs_daddr_t d;
747
748 ASSERT(fsbno != NULLFSBLOCK);
749 d = XFS_FSB_TO_DADDR(mp, fsbno);
1813dd64 750 xfs_buf_readahead(mp->m_ddev_targp, d, mp->m_bsize * count, ops);
1da177e4
LT		 751}
752
753/*
754 * Read-ahead the block, don't wait for it, don't return a buffer.
755 * Short-form addressing.
756 */
757/* ARGSUSED */
758void
759xfs_btree_reada_bufs(
3d3e6f64
DC		 760 struct xfs_mount *mp, /* file system mount point */
761 xfs_agnumber_t agno, /* allocation group number */
762 xfs_agblock_t agbno, /* allocation group block number */
763 xfs_extlen_t count, /* count of filesystem blocks */
1813dd64 764 const struct xfs_buf_ops *ops)
1da177e4
LT		 765{
766 xfs_daddr_t d;
767
768 ASSERT(agno != NULLAGNUMBER);
769 ASSERT(agbno != NULLAGBLOCK);
770 d = XFS_AGB_TO_DADDR(mp, agno, agbno);
1813dd64 771 xfs_buf_readahead(mp->m_ddev_targp, d, mp->m_bsize * count, ops);
1da177e4
LT		 772}
773
b524bfee
CH		 774STATIC int
775xfs_btree_readahead_lblock(
776 struct xfs_btree_cur *cur,
777 int lr,
778 struct xfs_btree_block *block)
779{
780 int rval = 0;
e6edbd1c
CH		 781 xfs_dfsbno_t left = be64_to_cpu(block->bb_u.l.bb_leftsib);
782 xfs_dfsbno_t right = be64_to_cpu(block->bb_u.l.bb_rightsib);
b524bfee
CH		 783
784 if ((lr & XFS_BTCUR_LEFTRA) && left != NULLDFSBNO) {
3d3e6f64 785 xfs_btree_reada_bufl(cur->bc_mp, left, 1,
1813dd64 786 cur->bc_ops->buf_ops);
b524bfee
CH		 787 rval++;
788 }
789
790 if ((lr & XFS_BTCUR_RIGHTRA) && right != NULLDFSBNO) {
3d3e6f64 791 xfs_btree_reada_bufl(cur->bc_mp, right, 1,
1813dd64 792 cur->bc_ops->buf_ops);
b524bfee
CH		 793 rval++;
794 }
795
796 return rval;
797}
798
799STATIC int
800xfs_btree_readahead_sblock(
801 struct xfs_btree_cur *cur,
802 int lr,
803 struct xfs_btree_block *block)
804{
805 int rval = 0;
806 xfs_agblock_t left = be32_to_cpu(block->bb_u.s.bb_leftsib);
807 xfs_agblock_t right = be32_to_cpu(block->bb_u.s.bb_rightsib);
808
809
810 if ((lr & XFS_BTCUR_LEFTRA) && left != NULLAGBLOCK) {
811 xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.a.agno,
1813dd64 812 left, 1, cur->bc_ops->buf_ops);
b524bfee
CH		 813 rval++;
814 }
815
816 if ((lr & XFS_BTCUR_RIGHTRA) && right != NULLAGBLOCK) {
817 xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.a.agno,
1813dd64 818 right, 1, cur->bc_ops->buf_ops);
b524bfee
CH		 819 rval++;
820 }
821
822 return rval;
823}
824
1da177e4
LT		 825/*
826 * Read-ahead btree blocks, at the given level.
827 * Bits in lr are set from XFS_BTCUR_{LEFT,RIGHT}RA.
828 */
3cc7524c 829STATIC int
b524bfee
CH		 830xfs_btree_readahead(
831 struct xfs_btree_cur *cur, /* btree cursor */
1da177e4
LT		 832 int lev, /* level in btree */
833 int lr) /* left/right bits */
834{
b524bfee
CH		 835 struct xfs_btree_block *block;
836
837 /*
838 * No readahead needed if we are at the root level and the
839 * btree root is stored in the inode.
840 */
841 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
842 (lev == cur->bc_nlevels - 1))
843 return 0;
844
845 if ((cur->bc_ra[lev] | lr) == cur->bc_ra[lev])
846 return 0;
1da177e4 847
1da177e4 848 cur->bc_ra[lev] |= lr;
b524bfee
CH		 849 block = XFS_BUF_TO_BLOCK(cur->bc_bufs[lev]);
850
851 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
852 return xfs_btree_readahead_lblock(cur, lr, block);
853 return xfs_btree_readahead_sblock(cur, lr, block);
1da177e4
LT		 854}
855
21b5c978
DC		 856STATIC xfs_daddr_t
857xfs_btree_ptr_to_daddr(
858 struct xfs_btree_cur *cur,
859 union xfs_btree_ptr *ptr)
860{
861 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
862 ASSERT(ptr->l != cpu_to_be64(NULLDFSBNO));
863
864 return XFS_FSB_TO_DADDR(cur->bc_mp, be64_to_cpu(ptr->l));
865 } else {
866 ASSERT(cur->bc_private.a.agno != NULLAGNUMBER);
867 ASSERT(ptr->s != cpu_to_be32(NULLAGBLOCK));
868
869 return XFS_AGB_TO_DADDR(cur->bc_mp, cur->bc_private.a.agno,
870 be32_to_cpu(ptr->s));
871 }
872}
873
874/*
875 * Readahead @count btree blocks at the given @ptr location.
876 *
877 * We don't need to care about long or short form btrees here as we have a
878 * method of converting the ptr directly to a daddr available to us.
879 */
880STATIC void
881xfs_btree_readahead_ptr(
882 struct xfs_btree_cur *cur,
883 union xfs_btree_ptr *ptr,
884 xfs_extlen_t count)
885{
886 xfs_buf_readahead(cur->bc_mp->m_ddev_targp,
887 xfs_btree_ptr_to_daddr(cur, ptr),
888 cur->bc_mp->m_bsize * count, cur->bc_ops->buf_ops);
889}
890
1da177e4
LT		 891/*
892 * Set the buffer for level "lev" in the cursor to bp, releasing
893 * any previous buffer.
894 */
c0e59e1a 895STATIC void
1da177e4
LT		 896xfs_btree_setbuf(
897 xfs_btree_cur_t *cur, /* btree cursor */
898 int lev, /* level in btree */
899 xfs_buf_t *bp) /* new buffer to set */
900{
7cc95a82 901 struct xfs_btree_block *b; /* btree block */
1da177e4 902
c0e59e1a
CH		 903 if (cur->bc_bufs[lev])
904 xfs_trans_brelse(cur->bc_tp, cur->bc_bufs[lev]);
1da177e4
LT		 905 cur->bc_bufs[lev] = bp;
906 cur->bc_ra[lev] = 0;
c0e59e1a 907
1da177e4 908 b = XFS_BUF_TO_BLOCK(bp);
e99ab90d 909 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
69ef921b 910 if (b->bb_u.l.bb_leftsib == cpu_to_be64(NULLDFSBNO))
1da177e4 911 cur->bc_ra[lev] |= XFS_BTCUR_LEFTRA;
69ef921b 912 if (b->bb_u.l.bb_rightsib == cpu_to_be64(NULLDFSBNO))
1da177e4
LT		 913 cur->bc_ra[lev] |= XFS_BTCUR_RIGHTRA;
914 } else {
69ef921b 915 if (b->bb_u.s.bb_leftsib == cpu_to_be32(NULLAGBLOCK))
1da177e4 916 cur->bc_ra[lev] |= XFS_BTCUR_LEFTRA;
69ef921b 917 if (b->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK))
1da177e4
LT		 918 cur->bc_ra[lev] |= XFS_BTCUR_RIGHTRA;
919 }
920}
637aa50f
CH		 921
922STATIC int
923xfs_btree_ptr_is_null(
924 struct xfs_btree_cur *cur,
925 union xfs_btree_ptr *ptr)
926{
927 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
69ef921b 928 return ptr->l == cpu_to_be64(NULLDFSBNO);
637aa50f 929 else
69ef921b 930 return ptr->s == cpu_to_be32(NULLAGBLOCK);
637aa50f
CH		 931}
932
4b22a571
CH		 933STATIC void
934xfs_btree_set_ptr_null(
935 struct xfs_btree_cur *cur,
936 union xfs_btree_ptr *ptr)
937{
938 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
33ad965d 939 ptr->l = cpu_to_be64(NULLDFSBNO);
4b22a571
CH		 940 else
941 ptr->s = cpu_to_be32(NULLAGBLOCK);
942}
943
637aa50f
CH		 944/*
945 * Get/set/init sibling pointers
946 */
947STATIC void
948xfs_btree_get_sibling(
949 struct xfs_btree_cur *cur,
950 struct xfs_btree_block *block,
951 union xfs_btree_ptr *ptr,
952 int lr)
953{
954 ASSERT(lr == XFS_BB_LEFTSIB || lr == XFS_BB_RIGHTSIB);
955
956 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
957 if (lr == XFS_BB_RIGHTSIB)
958 ptr->l = block->bb_u.l.bb_rightsib;
959 else
960 ptr->l = block->bb_u.l.bb_leftsib;
961 } else {
962 if (lr == XFS_BB_RIGHTSIB)
963 ptr->s = block->bb_u.s.bb_rightsib;
964 else
965 ptr->s = block->bb_u.s.bb_leftsib;
966 }
967}
968
f5eb8e7c
CH		 969STATIC void
970xfs_btree_set_sibling(
971 struct xfs_btree_cur *cur,
972 struct xfs_btree_block *block,
973 union xfs_btree_ptr *ptr,
974 int lr)
975{
976 ASSERT(lr == XFS_BB_LEFTSIB || lr == XFS_BB_RIGHTSIB);
977
978 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
979 if (lr == XFS_BB_RIGHTSIB)
980 block->bb_u.l.bb_rightsib = ptr->l;
981 else
982 block->bb_u.l.bb_leftsib = ptr->l;
983 } else {
984 if (lr == XFS_BB_RIGHTSIB)
985 block->bb_u.s.bb_rightsib = ptr->s;
986 else
987 block->bb_u.s.bb_leftsib = ptr->s;
988 }
989}
990
ee1a47ab
CH		 991void
992xfs_btree_init_block_int(
993 struct xfs_mount *mp,
994 struct xfs_btree_block *buf,
995 xfs_daddr_t blkno,
996 __u32 magic,
997 __u16 level,
998 __u16 numrecs,
999 __u64 owner,
1000 unsigned int flags)
1001{
1002 buf->bb_magic = cpu_to_be32(magic);
1003 buf->bb_level = cpu_to_be16(level);
1004 buf->bb_numrecs = cpu_to_be16(numrecs);
1005
1006 if (flags & XFS_BTREE_LONG_PTRS) {
1007 buf->bb_u.l.bb_leftsib = cpu_to_be64(NULLDFSBNO);
1008 buf->bb_u.l.bb_rightsib = cpu_to_be64(NULLDFSBNO);
1009 if (flags & XFS_BTREE_CRC_BLOCKS) {
1010 buf->bb_u.l.bb_blkno = cpu_to_be64(blkno);
1011 buf->bb_u.l.bb_owner = cpu_to_be64(owner);
1012 uuid_copy(&buf->bb_u.l.bb_uuid, &mp->m_sb.sb_uuid);
1013 buf->bb_u.l.bb_pad = 0;
b58fa554 1014 buf->bb_u.l.bb_lsn = 0;
ee1a47ab
CH		 1015 }
1016 } else {
1017 /* owner is a 32 bit value on short blocks */
1018 __u32 __owner = (__u32)owner;
1019
1020 buf->bb_u.s.bb_leftsib = cpu_to_be32(NULLAGBLOCK);
1021 buf->bb_u.s.bb_rightsib = cpu_to_be32(NULLAGBLOCK);
1022 if (flags & XFS_BTREE_CRC_BLOCKS) {
1023 buf->bb_u.s.bb_blkno = cpu_to_be64(blkno);
1024 buf->bb_u.s.bb_owner = cpu_to_be32(__owner);
1025 uuid_copy(&buf->bb_u.s.bb_uuid, &mp->m_sb.sb_uuid);
b58fa554 1026 buf->bb_u.s.bb_lsn = 0;
ee1a47ab
CH		 1027 }
1028 }
1029}
1030
b64f3a39 1031void
f5eb8e7c 1032xfs_btree_init_block(
b64f3a39
DC		 1033 struct xfs_mount *mp,
1034 struct xfs_buf *bp,
1035 __u32 magic,
1036 __u16 level,
1037 __u16 numrecs,
ee1a47ab 1038 __u64 owner,
b64f3a39 1039 unsigned int flags)
f5eb8e7c 1040{
ee1a47ab
CH		 1041 xfs_btree_init_block_int(mp, XFS_BUF_TO_BLOCK(bp), bp->b_bn,
1042 magic, level, numrecs, owner, flags);
f5eb8e7c
CH		 1043}
1044
b64f3a39
DC		 1045STATIC void
1046xfs_btree_init_block_cur(
1047 struct xfs_btree_cur *cur,
ee1a47ab 1048 struct xfs_buf *bp,
b64f3a39 1049 int level,
ee1a47ab 1050 int numrecs)
b64f3a39 1051{
ee1a47ab
CH		 1052 __u64 owner;
1053
1054 /*
1055 * we can pull the owner from the cursor right now as the different
1056 * owners align directly with the pointer size of the btree. This may
1057 * change in future, but is safe for current users of the generic btree
1058 * code.
1059 */
1060 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
1061 owner = cur->bc_private.b.ip->i_ino;
1062 else
1063 owner = cur->bc_private.a.agno;
1064
1065 xfs_btree_init_block_int(cur->bc_mp, XFS_BUF_TO_BLOCK(bp), bp->b_bn,
1066 xfs_btree_magic(cur), level, numrecs,
1067 owner, cur->bc_flags);
b64f3a39
DC		 1068}
1069
278d0ca1
CH		 1070/*
1071 * Return true if ptr is the last record in the btree and
ee1a47ab 1072 * we need to track updates to this record. The decision
278d0ca1
CH		 1073 * will be further refined in the update_lastrec method.
1074 */
1075STATIC int
1076xfs_btree_is_lastrec(
1077 struct xfs_btree_cur *cur,
1078 struct xfs_btree_block *block,
1079 int level)
1080{
1081 union xfs_btree_ptr ptr;
1082
1083 if (level > 0)
1084 return 0;
1085 if (!(cur->bc_flags & XFS_BTREE_LASTREC_UPDATE))
1086 return 0;
1087
1088 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
1089 if (!xfs_btree_ptr_is_null(cur, &ptr))
1090 return 0;
1091 return 1;
1092}
1093
f5eb8e7c
CH		 1094STATIC void
1095xfs_btree_buf_to_ptr(
1096 struct xfs_btree_cur *cur,
1097 struct xfs_buf *bp,
1098 union xfs_btree_ptr *ptr)
1099{
1100 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
1101 ptr->l = cpu_to_be64(XFS_DADDR_TO_FSB(cur->bc_mp,
1102 XFS_BUF_ADDR(bp)));
1103 else {
9d87c319 1104 ptr->s = cpu_to_be32(xfs_daddr_to_agbno(cur->bc_mp,
f5eb8e7c
CH		 1105 XFS_BUF_ADDR(bp)));
1106 }
1107}
1108
637aa50f
CH		 1109STATIC void
1110xfs_btree_set_refs(
1111 struct xfs_btree_cur *cur,
1112 struct xfs_buf *bp)
1113{
1114 switch (cur->bc_btnum) {
1115 case XFS_BTNUM_BNO:
1116 case XFS_BTNUM_CNT:
38f23232 1117 xfs_buf_set_ref(bp, XFS_ALLOC_BTREE_REF);
637aa50f
CH		 1118 break;
1119 case XFS_BTNUM_INO:
38f23232 1120 xfs_buf_set_ref(bp, XFS_INO_BTREE_REF);
637aa50f
CH		 1121 break;
1122 case XFS_BTNUM_BMAP:
38f23232 1123 xfs_buf_set_ref(bp, XFS_BMAP_BTREE_REF);
637aa50f
CH		 1124 break;
1125 default:
1126 ASSERT(0);
1127 }
1128}
1129
f5eb8e7c
CH		 1130STATIC int
1131xfs_btree_get_buf_block(
1132 struct xfs_btree_cur *cur,
1133 union xfs_btree_ptr *ptr,
1134 int flags,
1135 struct xfs_btree_block **block,
1136 struct xfs_buf **bpp)
1137{
1138 struct xfs_mount *mp = cur->bc_mp;
1139 xfs_daddr_t d;
1140
1141 /* need to sort out how callers deal with failures first */
0cadda1c 1142 ASSERT(!(flags & XBF_TRYLOCK));
f5eb8e7c
CH		 1143
1144 d = xfs_btree_ptr_to_daddr(cur, ptr);
1145 *bpp = xfs_trans_get_buf(cur->bc_tp, mp->m_ddev_targp, d,
1146 mp->m_bsize, flags);
1147
2a30f36d
CS		 1148 if (!*bpp)
1149 return ENOMEM;
f5eb8e7c 1150
1813dd64 1151 (*bpp)->b_ops = cur->bc_ops->buf_ops;
f5eb8e7c
CH		 1152 *block = XFS_BUF_TO_BLOCK(*bpp);
1153 return 0;
1154}
1155
637aa50f
CH		 1156/*
1157 * Read in the buffer at the given ptr and return the buffer and
1158 * the block pointer within the buffer.
1159 */
1160STATIC int
1161xfs_btree_read_buf_block(
1162 struct xfs_btree_cur *cur,
1163 union xfs_btree_ptr *ptr,
1164 int level,
1165 int flags,
1166 struct xfs_btree_block **block,
1167 struct xfs_buf **bpp)
1168{
1169 struct xfs_mount *mp = cur->bc_mp;
1170 xfs_daddr_t d;
1171 int error;
1172
1173 /* need to sort out how callers deal with failures first */
0cadda1c 1174 ASSERT(!(flags & XBF_TRYLOCK));
637aa50f
CH		 1175
1176 d = xfs_btree_ptr_to_daddr(cur, ptr);
1177 error = xfs_trans_read_buf(mp, cur->bc_tp, mp->m_ddev_targp, d,
3d3e6f64 1178 mp->m_bsize, flags, bpp,
1813dd64 1179 cur->bc_ops->buf_ops);
637aa50f
CH		 1180 if (error)
1181 return error;
1182
5a52c2a5 1183 ASSERT(!xfs_buf_geterror(*bpp));
637aa50f
CH		 1184 xfs_btree_set_refs(cur, *bpp);
1185 *block = XFS_BUF_TO_BLOCK(*bpp);
3d3e6f64 1186 return 0;
637aa50f
CH		 1187}
1188
38bb7423
CH		 1189/*
1190 * Copy keys from one btree block to another.
1191 */
1192STATIC void
1193xfs_btree_copy_keys(
1194 struct xfs_btree_cur *cur,
1195 union xfs_btree_key *dst_key,
1196 union xfs_btree_key *src_key,
1197 int numkeys)
1198{
1199 ASSERT(numkeys >= 0);
1200 memcpy(dst_key, src_key, numkeys * cur->bc_ops->key_len);
1201}
1202
278d0ca1
CH		 1203/*
1204 * Copy records from one btree block to another.
1205 */
1206STATIC void
1207xfs_btree_copy_recs(
1208 struct xfs_btree_cur *cur,
1209 union xfs_btree_rec *dst_rec,
1210 union xfs_btree_rec *src_rec,
1211 int numrecs)
1212{
1213 ASSERT(numrecs >= 0);
1214 memcpy(dst_rec, src_rec, numrecs * cur->bc_ops->rec_len);
1215}
1216
9eaead51
CH		 1217/*
1218 * Copy block pointers from one btree block to another.
1219 */
1220STATIC void
1221xfs_btree_copy_ptrs(
1222 struct xfs_btree_cur *cur,
1223 union xfs_btree_ptr *dst_ptr,
1224 union xfs_btree_ptr *src_ptr,
1225 int numptrs)
1226{
1227 ASSERT(numptrs >= 0);
1228 memcpy(dst_ptr, src_ptr, numptrs * xfs_btree_ptr_len(cur));
1229}
1230
1231/*
1232 * Shift keys one index left/right inside a single btree block.
1233 */
1234STATIC void
1235xfs_btree_shift_keys(
1236 struct xfs_btree_cur *cur,
1237 union xfs_btree_key *key,
1238 int dir,
1239 int numkeys)
1240{
1241 char *dst_key;
1242
1243 ASSERT(numkeys >= 0);
1244 ASSERT(dir == 1 || dir == -1);
1245
1246 dst_key = (char *)key + (dir * cur->bc_ops->key_len);
1247 memmove(dst_key, key, numkeys * cur->bc_ops->key_len);
1248}
1249
1250/*
1251 * Shift records one index left/right inside a single btree block.
1252 */
1253STATIC void
1254xfs_btree_shift_recs(
1255 struct xfs_btree_cur *cur,
1256 union xfs_btree_rec *rec,
1257 int dir,
1258 int numrecs)
1259{
1260 char *dst_rec;
1261
1262 ASSERT(numrecs >= 0);
1263 ASSERT(dir == 1 || dir == -1);
1264
1265 dst_rec = (char *)rec + (dir * cur->bc_ops->rec_len);
1266 memmove(dst_rec, rec, numrecs * cur->bc_ops->rec_len);
1267}
1268
1269/*
1270 * Shift block pointers one index left/right inside a single btree block.
1271 */
1272STATIC void
1273xfs_btree_shift_ptrs(
1274 struct xfs_btree_cur *cur,
1275 union xfs_btree_ptr *ptr,
1276 int dir,
1277 int numptrs)
1278{
1279 char *dst_ptr;
1280
1281 ASSERT(numptrs >= 0);
1282 ASSERT(dir == 1 || dir == -1);
1283
1284 dst_ptr = (char *)ptr + (dir * xfs_btree_ptr_len(cur));
1285 memmove(dst_ptr, ptr, numptrs * xfs_btree_ptr_len(cur));
1286}
1287
38bb7423
CH		 1288/*
1289 * Log key values from the btree block.
1290 */
1291STATIC void
1292xfs_btree_log_keys(
1293 struct xfs_btree_cur *cur,
1294 struct xfs_buf *bp,
1295 int first,
1296 int last)
1297{
1298 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1299 XFS_BTREE_TRACE_ARGBII(cur, bp, first, last);
1300
1301 if (bp) {
61fe135c 1302 xfs_trans_buf_set_type(cur->bc_tp, bp, XFS_BLFT_BTREE_BUF);
38bb7423
CH		 1303 xfs_trans_log_buf(cur->bc_tp, bp,
1304 xfs_btree_key_offset(cur, first),
1305 xfs_btree_key_offset(cur, last + 1) - 1);
1306 } else {
1307 xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip,
1308 xfs_ilog_fbroot(cur->bc_private.b.whichfork));
1309 }
1310
1311 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1312}
1313
278d0ca1
CH		 1314/*
1315 * Log record values from the btree block.
1316 */
fd6bcc5b 1317void
278d0ca1
CH		 1318xfs_btree_log_recs(
1319 struct xfs_btree_cur *cur,
1320 struct xfs_buf *bp,
1321 int first,
1322 int last)
1323{
1324 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1325 XFS_BTREE_TRACE_ARGBII(cur, bp, first, last);
1326
61fe135c 1327 xfs_trans_buf_set_type(cur->bc_tp, bp, XFS_BLFT_BTREE_BUF);
278d0ca1
CH		 1328 xfs_trans_log_buf(cur->bc_tp, bp,
1329 xfs_btree_rec_offset(cur, first),
1330 xfs_btree_rec_offset(cur, last + 1) - 1);
1331
1332 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1333}
1334
9eaead51
CH		 1335/*
1336 * Log block pointer fields from a btree block (nonleaf).
1337 */
1338STATIC void
1339xfs_btree_log_ptrs(
1340 struct xfs_btree_cur *cur, /* btree cursor */
1341 struct xfs_buf *bp, /* buffer containing btree block */
1342 int first, /* index of first pointer to log */
1343 int last) /* index of last pointer to log */
1344{
1345 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1346 XFS_BTREE_TRACE_ARGBII(cur, bp, first, last);
1347
1348 if (bp) {
1349 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
1350 int level = xfs_btree_get_level(block);
1351
61fe135c 1352 xfs_trans_buf_set_type(cur->bc_tp, bp, XFS_BLFT_BTREE_BUF);
9eaead51
CH		 1353 xfs_trans_log_buf(cur->bc_tp, bp,
1354 xfs_btree_ptr_offset(cur, first, level),
1355 xfs_btree_ptr_offset(cur, last + 1, level) - 1);
1356 } else {
1357 xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip,
1358 xfs_ilog_fbroot(cur->bc_private.b.whichfork));
1359 }
1360
1361 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1362}
1363
1364/*
1365 * Log fields from a btree block header.
1366 */
fd6bcc5b 1367void
9eaead51
CH		 1368xfs_btree_log_block(
1369 struct xfs_btree_cur *cur, /* btree cursor */
1370 struct xfs_buf *bp, /* buffer containing btree block */
1371 int fields) /* mask of fields: XFS_BB_... */
1372{
1373 int first; /* first byte offset logged */
1374 int last; /* last byte offset logged */
1375 static const short soffsets[] = { /* table of offsets (short) */
7cc95a82
CH		 1376 offsetof(struct xfs_btree_block, bb_magic),
1377 offsetof(struct xfs_btree_block, bb_level),
1378 offsetof(struct xfs_btree_block, bb_numrecs),
1379 offsetof(struct xfs_btree_block, bb_u.s.bb_leftsib),
1380 offsetof(struct xfs_btree_block, bb_u.s.bb_rightsib),
ee1a47ab
CH		 1381 offsetof(struct xfs_btree_block, bb_u.s.bb_blkno),
1382 offsetof(struct xfs_btree_block, bb_u.s.bb_lsn),
1383 offsetof(struct xfs_btree_block, bb_u.s.bb_uuid),
1384 offsetof(struct xfs_btree_block, bb_u.s.bb_owner),
1385 offsetof(struct xfs_btree_block, bb_u.s.bb_crc),
1386 XFS_BTREE_SBLOCK_CRC_LEN
9eaead51
CH		 1387 };
1388 static const short loffsets[] = { /* table of offsets (long) */
7cc95a82
CH		 1389 offsetof(struct xfs_btree_block, bb_magic),
1390 offsetof(struct xfs_btree_block, bb_level),
1391 offsetof(struct xfs_btree_block, bb_numrecs),
1392 offsetof(struct xfs_btree_block, bb_u.l.bb_leftsib),
1393 offsetof(struct xfs_btree_block, bb_u.l.bb_rightsib),
ee1a47ab
CH		 1394 offsetof(struct xfs_btree_block, bb_u.l.bb_blkno),
1395 offsetof(struct xfs_btree_block, bb_u.l.bb_lsn),
1396 offsetof(struct xfs_btree_block, bb_u.l.bb_uuid),
1397 offsetof(struct xfs_btree_block, bb_u.l.bb_owner),
1398 offsetof(struct xfs_btree_block, bb_u.l.bb_crc),
1399 offsetof(struct xfs_btree_block, bb_u.l.bb_pad),
1400 XFS_BTREE_LBLOCK_CRC_LEN
9eaead51
CH		 1401 };
1402
1403 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1404 XFS_BTREE_TRACE_ARGBI(cur, bp, fields);
1405
1406 if (bp) {
ee1a47ab
CH		 1407 int nbits;
1408
1409 if (cur->bc_flags & XFS_BTREE_CRC_BLOCKS) {
1410 /*
1411 * We don't log the CRC when updating a btree
1412 * block but instead recreate it during log
1413 * recovery. As the log buffers have checksums
1414 * of their own this is safe and avoids logging a crc
1415 * update in a lot of places.
1416 */
1417 if (fields == XFS_BB_ALL_BITS)
1418 fields = XFS_BB_ALL_BITS_CRC;
1419 nbits = XFS_BB_NUM_BITS_CRC;
1420 } else {
1421 nbits = XFS_BB_NUM_BITS;
1422 }
9eaead51
CH		 1423 xfs_btree_offsets(fields,
1424 (cur->bc_flags & XFS_BTREE_LONG_PTRS) ?
1425 loffsets : soffsets,
ee1a47ab 1426 nbits, &first, &last);
61fe135c 1427 xfs_trans_buf_set_type(cur->bc_tp, bp, XFS_BLFT_BTREE_BUF);
9eaead51
CH		 1428 xfs_trans_log_buf(cur->bc_tp, bp, first, last);
1429 } else {
1430 xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip,
1431 xfs_ilog_fbroot(cur->bc_private.b.whichfork));
1432 }
1433
1434 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1435}
1436
637aa50f
CH		 1437/*
1438 * Increment cursor by one record at the level.
1439 * For nonzero levels the leaf-ward information is untouched.
1440 */
1441int /* error */
1442xfs_btree_increment(
1443 struct xfs_btree_cur *cur,
1444 int level,
1445 int *stat) /* success/failure */
1446{
1447 struct xfs_btree_block *block;
1448 union xfs_btree_ptr ptr;
1449 struct xfs_buf *bp;
1450 int error; /* error return value */
1451 int lev;
1452
1453 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1454 XFS_BTREE_TRACE_ARGI(cur, level);
1455
1456 ASSERT(level < cur->bc_nlevels);
1457
1458 /* Read-ahead to the right at this level. */
1459 xfs_btree_readahead(cur, level, XFS_BTCUR_RIGHTRA);
1460
1461 /* Get a pointer to the btree block. */
1462 block = xfs_btree_get_block(cur, level, &bp);
1463
1464#ifdef DEBUG
1465 error = xfs_btree_check_block(cur, block, level, bp);
1466 if (error)
1467 goto error0;
1468#endif
1469
1470 /* We're done if we remain in the block after the increment. */
1471 if (++cur->bc_ptrs[level] <= xfs_btree_get_numrecs(block))
1472 goto out1;
1473
1474 /* Fail if we just went off the right edge of the tree. */
1475 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
1476 if (xfs_btree_ptr_is_null(cur, &ptr))
1477 goto out0;
1478
1479 XFS_BTREE_STATS_INC(cur, increment);
1480
1481 /*
1482 * March up the tree incrementing pointers.
1483 * Stop when we don't go off the right edge of a block.
1484 */
1485 for (lev = level + 1; lev < cur->bc_nlevels; lev++) {
1486 block = xfs_btree_get_block(cur, lev, &bp);
1487
1488#ifdef DEBUG
1489 error = xfs_btree_check_block(cur, block, lev, bp);
1490 if (error)
1491 goto error0;
1492#endif
1493
1494 if (++cur->bc_ptrs[lev] <= xfs_btree_get_numrecs(block))
1495 break;
1496
1497 /* Read-ahead the right block for the next loop. */
1498 xfs_btree_readahead(cur, lev, XFS_BTCUR_RIGHTRA);
1499 }
1500
1501 /*
1502 * If we went off the root then we are either seriously
1503 * confused or have the tree root in an inode.
1504 */
1505 if (lev == cur->bc_nlevels) {
1506 if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE)
1507 goto out0;
1508 ASSERT(0);
1509 error = EFSCORRUPTED;
1510 goto error0;
1511 }
1512 ASSERT(lev < cur->bc_nlevels);
1513
1514 /*
1515 * Now walk back down the tree, fixing up the cursor's buffer
1516 * pointers and key numbers.
1517 */
1518 for (block = xfs_btree_get_block(cur, lev, &bp); lev > level; ) {
1519 union xfs_btree_ptr *ptrp;
1520
1521 ptrp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[lev], block);
1522 error = xfs_btree_read_buf_block(cur, ptrp, --lev,
1523 0, &block, &bp);
1524 if (error)
1525 goto error0;
1526
1527 xfs_btree_setbuf(cur, lev, bp);
1528 cur->bc_ptrs[lev] = 1;
1529 }
1530out1:
1531 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1532 *stat = 1;
1533 return 0;
1534
1535out0:
1536 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1537 *stat = 0;
1538 return 0;
1539
1540error0:
1541 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
1542 return error;
1543}
8df4da4a
CH		 1544
1545/*
1546 * Decrement cursor by one record at the level.
1547 * For nonzero levels the leaf-ward information is untouched.
1548 */
1549int /* error */
1550xfs_btree_decrement(
1551 struct xfs_btree_cur *cur,
1552 int level,
1553 int *stat) /* success/failure */
1554{
1555 struct xfs_btree_block *block;
1556 xfs_buf_t *bp;
1557 int error; /* error return value */
1558 int lev;
1559 union xfs_btree_ptr ptr;
1560
1561 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1562 XFS_BTREE_TRACE_ARGI(cur, level);
1563
1564 ASSERT(level < cur->bc_nlevels);
1565
1566 /* Read-ahead to the left at this level. */
1567 xfs_btree_readahead(cur, level, XFS_BTCUR_LEFTRA);
1568
1569 /* We're done if we remain in the block after the decrement. */
1570 if (--cur->bc_ptrs[level] > 0)
1571 goto out1;
1572
1573 /* Get a pointer to the btree block. */
1574 block = xfs_btree_get_block(cur, level, &bp);
1575
1576#ifdef DEBUG
1577 error = xfs_btree_check_block(cur, block, level, bp);
1578 if (error)
1579 goto error0;
1580#endif
1581
1582 /* Fail if we just went off the left edge of the tree. */
1583 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_LEFTSIB);
1584 if (xfs_btree_ptr_is_null(cur, &ptr))
1585 goto out0;
1586
1587 XFS_BTREE_STATS_INC(cur, decrement);
1588
1589 /*
1590 * March up the tree decrementing pointers.
1591 * Stop when we don't go off the left edge of a block.
1592 */
1593 for (lev = level + 1; lev < cur->bc_nlevels; lev++) {
1594 if (--cur->bc_ptrs[lev] > 0)
1595 break;
1596 /* Read-ahead the left block for the next loop. */
1597 xfs_btree_readahead(cur, lev, XFS_BTCUR_LEFTRA);
1598 }
1599
1600 /*
1601 * If we went off the root then we are seriously confused.
1602 * or the root of the tree is in an inode.
1603 */
1604 if (lev == cur->bc_nlevels) {
1605 if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE)
1606 goto out0;
1607 ASSERT(0);
1608 error = EFSCORRUPTED;
1609 goto error0;
1610 }
1611 ASSERT(lev < cur->bc_nlevels);
1612
1613 /*
1614 * Now walk back down the tree, fixing up the cursor's buffer
1615 * pointers and key numbers.
1616 */
1617 for (block = xfs_btree_get_block(cur, lev, &bp); lev > level; ) {
1618 union xfs_btree_ptr *ptrp;
1619
1620 ptrp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[lev], block);
1621 error = xfs_btree_read_buf_block(cur, ptrp, --lev,
1622 0, &block, &bp);
1623 if (error)
1624 goto error0;
1625 xfs_btree_setbuf(cur, lev, bp);
1626 cur->bc_ptrs[lev] = xfs_btree_get_numrecs(block);
1627 }
1628out1:
1629 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1630 *stat = 1;
1631 return 0;
1632
1633out0:
1634 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1635 *stat = 0;
1636 return 0;
1637
1638error0:
1639 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
1640 return error;
1641}
1642
fe033cc8
CH		 1643STATIC int
1644xfs_btree_lookup_get_block(
1645 struct xfs_btree_cur *cur, /* btree cursor */
1646 int level, /* level in the btree */
1647 union xfs_btree_ptr *pp, /* ptr to btree block */
1648 struct xfs_btree_block **blkp) /* return btree block */
1649{
1650 struct xfs_buf *bp; /* buffer pointer for btree block */
1651 int error = 0;
1652
1653 /* special case the root block if in an inode */
1654 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
1655 (level == cur->bc_nlevels - 1)) {
1656 *blkp = xfs_btree_get_iroot(cur);
1657 return 0;
1658 }
1659
1660 /*
1661 * If the old buffer at this level for the disk address we are
1662 * looking for re-use it.
1663 *
1664 * Otherwise throw it away and get a new one.
1665 */
1666 bp = cur->bc_bufs[level];
1667 if (bp && XFS_BUF_ADDR(bp) == xfs_btree_ptr_to_daddr(cur, pp)) {
1668 *blkp = XFS_BUF_TO_BLOCK(bp);
1669 return 0;
1670 }
1671
1672 error = xfs_btree_read_buf_block(cur, pp, level, 0, blkp, &bp);
1673 if (error)
1674 return error;
1675
1676 xfs_btree_setbuf(cur, level, bp);
1677 return 0;
1678}
1679
1680/*
1681 * Get current search key. For level 0 we don't actually have a key
1682 * structure so we make one up from the record. For all other levels
1683 * we just return the right key.
1684 */
1685STATIC union xfs_btree_key *
1686xfs_lookup_get_search_key(
1687 struct xfs_btree_cur *cur,
1688 int level,
1689 int keyno,
1690 struct xfs_btree_block *block,
1691 union xfs_btree_key *kp)
1692{
1693 if (level == 0) {
1694 cur->bc_ops->init_key_from_rec(kp,
1695 xfs_btree_rec_addr(cur, keyno, block));
1696 return kp;
1697 }
1698
1699 return xfs_btree_key_addr(cur, keyno, block);
1700}
1701
1702/*
1703 * Lookup the record. The cursor is made to point to it, based on dir.
49d3da14 1704 * stat is set to 0 if can't find any such record, 1 for success.
fe033cc8
CH		 1705 */
1706int /* error */
1707xfs_btree_lookup(
1708 struct xfs_btree_cur *cur, /* btree cursor */
1709 xfs_lookup_t dir, /* <=, ==, or >= */
1710 int *stat) /* success/failure */
1711{
1712 struct xfs_btree_block *block; /* current btree block */
1713 __int64_t diff; /* difference for the current key */
1714 int error; /* error return value */
1715 int keyno; /* current key number */
1716 int level; /* level in the btree */
1717 union xfs_btree_ptr *pp; /* ptr to btree block */
1718 union xfs_btree_ptr ptr; /* ptr to btree block */
1719
1720 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1721 XFS_BTREE_TRACE_ARGI(cur, dir);
1722
1723 XFS_BTREE_STATS_INC(cur, lookup);
1724
1725 block = NULL;
1726 keyno = 0;
1727
1728 /* initialise start pointer from cursor */
1729 cur->bc_ops->init_ptr_from_cur(cur, &ptr);
1730 pp = &ptr;
1731
1732 /*
1733 * Iterate over each level in the btree, starting at the root.
1734 * For each level above the leaves, find the key we need, based
1735 * on the lookup record, then follow the corresponding block
1736 * pointer down to the next level.
1737 */
1738 for (level = cur->bc_nlevels - 1, diff = 1; level >= 0; level--) {
1739 /* Get the block we need to do the lookup on. */
1740 error = xfs_btree_lookup_get_block(cur, level, pp, &block);
1741 if (error)
1742 goto error0;
1743
1744 if (diff == 0) {
1745 /*
1746 * If we already had a key match at a higher level, we
1747 * know we need to use the first entry in this block.
1748 */
1749 keyno = 1;
1750 } else {
1751 /* Otherwise search this block. Do a binary search. */
1752
1753 int high; /* high entry number */
1754 int low; /* low entry number */
1755
1756 /* Set low and high entry numbers, 1-based. */
1757 low = 1;
1758 high = xfs_btree_get_numrecs(block);
1759 if (!high) {
1760 /* Block is empty, must be an empty leaf. */
1761 ASSERT(level == 0 && cur->bc_nlevels == 1);
1762
1763 cur->bc_ptrs[0] = dir != XFS_LOOKUP_LE;
1764 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1765 *stat = 0;
1766 return 0;
1767 }
1768
1769 /* Binary search the block. */
1770 while (low <= high) {
1771 union xfs_btree_key key;
1772 union xfs_btree_key *kp;
1773
1774 XFS_BTREE_STATS_INC(cur, compare);
1775
1776 /* keyno is average of low and high. */
1777 keyno = (low + high) >> 1;
1778
1779 /* Get current search key */
1780 kp = xfs_lookup_get_search_key(cur, level,
1781 keyno, block, &key);
1782
1783 /*
1784 * Compute difference to get next direction:
1785 * - less than, move right
1786 * - greater than, move left
1787 * - equal, we're done
1788 */
1789 diff = cur->bc_ops->key_diff(cur, kp);
1790 if (diff < 0)
1791 low = keyno + 1;
1792 else if (diff > 0)
1793 high = keyno - 1;
1794 else
1795 break;
1796 }
1797 }
1798
1799 /*
1800 * If there are more levels, set up for the next level
1801 * by getting the block number and filling in the cursor.
1802 */
1803 if (level > 0) {
1804 /*
1805 * If we moved left, need the previous key number,
1806 * unless there isn't one.
1807 */
1808 if (diff > 0 && --keyno < 1)
1809 keyno = 1;
1810 pp = xfs_btree_ptr_addr(cur, keyno, block);
1811
1812#ifdef DEBUG
1813 error = xfs_btree_check_ptr(cur, pp, 0, level);
1814 if (error)
1815 goto error0;
1816#endif
1817 cur->bc_ptrs[level] = keyno;
1818 }
1819 }
1820
1821 /* Done with the search. See if we need to adjust the results. */
1822 if (dir != XFS_LOOKUP_LE && diff < 0) {
1823 keyno++;
1824 /*
1825 * If ge search and we went off the end of the block, but it's
1826 * not the last block, we're in the wrong block.
1827 */
1828 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
1829 if (dir == XFS_LOOKUP_GE &&
1830 keyno > xfs_btree_get_numrecs(block) &&
1831 !xfs_btree_ptr_is_null(cur, &ptr)) {
1832 int i;
1833
1834 cur->bc_ptrs[0] = keyno;
1835 error = xfs_btree_increment(cur, 0, &i);
1836 if (error)
1837 goto error0;
1838 XFS_WANT_CORRUPTED_RETURN(i == 1);
1839 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1840 *stat = 1;
1841 return 0;
1842 }
1843 } else if (dir == XFS_LOOKUP_LE && diff > 0)
1844 keyno--;
1845 cur->bc_ptrs[0] = keyno;
1846
1847 /* Return if we succeeded or not. */
1848 if (keyno == 0 || keyno > xfs_btree_get_numrecs(block))
1849 *stat = 0;
1850 else if (dir != XFS_LOOKUP_EQ || diff == 0)
1851 *stat = 1;
1852 else
1853 *stat = 0;
1854 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1855 return 0;
1856
1857error0:
1858 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
1859 return error;
1860}
38bb7423
CH		 1861
1862/*
1863 * Update keys at all levels from here to the root along the cursor's path.
1864 */
3cc7524c 1865STATIC int
38bb7423
CH		 1866xfs_btree_updkey(
1867 struct xfs_btree_cur *cur,
1868 union xfs_btree_key *keyp,
1869 int level)
1870{
1871 struct xfs_btree_block *block;
1872 struct xfs_buf *bp;
1873 union xfs_btree_key *kp;
1874 int ptr;
1875
1876 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1877 XFS_BTREE_TRACE_ARGIK(cur, level, keyp);
1878
1879 ASSERT(!(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) || level >= 1);
1880
1881 /*
1882 * Go up the tree from this level toward the root.
1883 * At each level, update the key value to the value input.
1884 * Stop when we reach a level where the cursor isn't pointing
1885 * at the first entry in the block.
1886 */
1887 for (ptr = 1; ptr == 1 && level < cur->bc_nlevels; level++) {
1888#ifdef DEBUG
1889 int error;
1890#endif
1891 block = xfs_btree_get_block(cur, level, &bp);
1892#ifdef DEBUG
1893 error = xfs_btree_check_block(cur, block, level, bp);
1894 if (error) {
1895 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
1896 return error;
1897 }
1898#endif
1899 ptr = cur->bc_ptrs[level];
1900 kp = xfs_btree_key_addr(cur, ptr, block);
1901 xfs_btree_copy_keys(cur, kp, keyp, 1);
1902 xfs_btree_log_keys(cur, bp, ptr, ptr);
1903 }
1904
1905 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1906 return 0;
1907}
278d0ca1
CH		 1908
1909/*
1910 * Update the record referred to by cur to the value in the
1911 * given record. This either works (return 0) or gets an
1912 * EFSCORRUPTED error.
1913 */
1914int
1915xfs_btree_update(
1916 struct xfs_btree_cur *cur,
1917 union xfs_btree_rec *rec)
1918{
1919 struct xfs_btree_block *block;
1920 struct xfs_buf *bp;
1921 int error;
1922 int ptr;
1923 union xfs_btree_rec *rp;
1924
1925 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1926 XFS_BTREE_TRACE_ARGR(cur, rec);
1927
1928 /* Pick up the current block. */
1929 block = xfs_btree_get_block(cur, 0, &bp);
1930
1931#ifdef DEBUG
1932 error = xfs_btree_check_block(cur, block, 0, bp);
1933 if (error)
1934 goto error0;
1935#endif
1936 /* Get the address of the rec to be updated. */
1937 ptr = cur->bc_ptrs[0];
1938 rp = xfs_btree_rec_addr(cur, ptr, block);
1939
1940 /* Fill in the new contents and log them. */
1941 xfs_btree_copy_recs(cur, rp, rec, 1);
1942 xfs_btree_log_recs(cur, bp, ptr, ptr);
1943
1944 /*
1945 * If we are tracking the last record in the tree and
1946 * we are at the far right edge of the tree, update it.
1947 */
1948 if (xfs_btree_is_lastrec(cur, block, 0)) {
1949 cur->bc_ops->update_lastrec(cur, block, rec,
1950 ptr, LASTREC_UPDATE);
1951 }
1952
1953 /* Updating first rec in leaf. Pass new key value up to our parent. */
1954 if (ptr == 1) {
1955 union xfs_btree_key key;
1956
1957 cur->bc_ops->init_key_from_rec(&key, rec);
1958 error = xfs_btree_updkey(cur, &key, 1);
1959 if (error)
1960 goto error0;
1961 }
1962
1963 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1964 return 0;
1965
1966error0:
1967 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
1968 return error;
1969}
1970
687b890a
CH		 1971/*
1972 * Move 1 record left from cur/level if possible.
1973 * Update cur to reflect the new path.
1974 */
3cc7524c 1975STATIC int /* error */
687b890a
CH		 1976xfs_btree_lshift(
1977 struct xfs_btree_cur *cur,
1978 int level,
1979 int *stat) /* success/failure */
1980{
1981 union xfs_btree_key key; /* btree key */
1982 struct xfs_buf *lbp; /* left buffer pointer */
1983 struct xfs_btree_block *left; /* left btree block */
1984 int lrecs; /* left record count */
1985 struct xfs_buf *rbp; /* right buffer pointer */
1986 struct xfs_btree_block *right; /* right btree block */
1987 int rrecs; /* right record count */
1988 union xfs_btree_ptr lptr; /* left btree pointer */
1989 union xfs_btree_key *rkp = NULL; /* right btree key */
1990 union xfs_btree_ptr *rpp = NULL; /* right address pointer */
1991 union xfs_btree_rec *rrp = NULL; /* right record pointer */
1992 int error; /* error return value */
1993
1994 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1995 XFS_BTREE_TRACE_ARGI(cur, level);
1996
1997 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
1998 level == cur->bc_nlevels - 1)
1999 goto out0;
2000
2001 /* Set up variables for this block as "right". */
2002 right = xfs_btree_get_block(cur, level, &rbp);
2003
2004#ifdef DEBUG
2005 error = xfs_btree_check_block(cur, right, level, rbp);
2006 if (error)
2007 goto error0;
2008#endif
2009
2010 /* If we've got no left sibling then we can't shift an entry left. */
2011 xfs_btree_get_sibling(cur, right, &lptr, XFS_BB_LEFTSIB);
2012 if (xfs_btree_ptr_is_null(cur, &lptr))
2013 goto out0;
2014
2015 /*
2016 * If the cursor entry is the one that would be moved, don't
2017 * do it... it's too complicated.
2018 */
2019 if (cur->bc_ptrs[level] <= 1)
2020 goto out0;
2021
2022 /* Set up the left neighbor as "left". */
2023 error = xfs_btree_read_buf_block(cur, &lptr, level, 0, &left, &lbp);
2024 if (error)
2025 goto error0;
2026
2027 /* If it's full, it can't take another entry. */
2028 lrecs = xfs_btree_get_numrecs(left);
2029 if (lrecs == cur->bc_ops->get_maxrecs(cur, level))
2030 goto out0;
2031
2032 rrecs = xfs_btree_get_numrecs(right);
2033
2034 /*
2035 * We add one entry to the left side and remove one for the right side.
9da096fd 2036 * Account for it here, the changes will be updated on disk and logged
687b890a
CH		 2037 * later.
2038 */
2039 lrecs++;
2040 rrecs--;
2041
2042 XFS_BTREE_STATS_INC(cur, lshift);
2043 XFS_BTREE_STATS_ADD(cur, moves, 1);
2044
2045 /*
2046 * If non-leaf, copy a key and a ptr to the left block.
2047 * Log the changes to the left block.
2048 */
2049 if (level > 0) {
2050 /* It's a non-leaf. Move keys and pointers. */
2051 union xfs_btree_key *lkp; /* left btree key */
2052 union xfs_btree_ptr *lpp; /* left address pointer */
2053
2054 lkp = xfs_btree_key_addr(cur, lrecs, left);
2055 rkp = xfs_btree_key_addr(cur, 1, right);
2056
2057 lpp = xfs_btree_ptr_addr(cur, lrecs, left);
2058 rpp = xfs_btree_ptr_addr(cur, 1, right);
2059#ifdef DEBUG
2060 error = xfs_btree_check_ptr(cur, rpp, 0, level);
2061 if (error)
2062 goto error0;
2063#endif
2064 xfs_btree_copy_keys(cur, lkp, rkp, 1);
2065 xfs_btree_copy_ptrs(cur, lpp, rpp, 1);
2066
2067 xfs_btree_log_keys(cur, lbp, lrecs, lrecs);
2068 xfs_btree_log_ptrs(cur, lbp, lrecs, lrecs);
2069
4a26e66e
CH		 2070 ASSERT(cur->bc_ops->keys_inorder(cur,
2071 xfs_btree_key_addr(cur, lrecs - 1, left), lkp));
687b890a
CH		 2072 } else {
2073 /* It's a leaf. Move records. */
2074 union xfs_btree_rec *lrp; /* left record pointer */
2075
2076 lrp = xfs_btree_rec_addr(cur, lrecs, left);
2077 rrp = xfs_btree_rec_addr(cur, 1, right);
2078
2079 xfs_btree_copy_recs(cur, lrp, rrp, 1);
2080 xfs_btree_log_recs(cur, lbp, lrecs, lrecs);
2081
4a26e66e
CH		 2082 ASSERT(cur->bc_ops->recs_inorder(cur,
2083 xfs_btree_rec_addr(cur, lrecs - 1, left), lrp));
687b890a
CH		 2084 }
2085
2086 xfs_btree_set_numrecs(left, lrecs);
2087 xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS);
2088
2089 xfs_btree_set_numrecs(right, rrecs);
2090 xfs_btree_log_block(cur, rbp, XFS_BB_NUMRECS);
2091
2092 /*
2093 * Slide the contents of right down one entry.
2094 */
2095 XFS_BTREE_STATS_ADD(cur, moves, rrecs - 1);
2096 if (level > 0) {
2097 /* It's a nonleaf. operate on keys and ptrs */
2098#ifdef DEBUG
2099 int i; /* loop index */
2100
2101 for (i = 0; i < rrecs; i++) {
2102 error = xfs_btree_check_ptr(cur, rpp, i + 1, level);
2103 if (error)
2104 goto error0;
2105 }
2106#endif
2107 xfs_btree_shift_keys(cur,
2108 xfs_btree_key_addr(cur, 2, right),
2109 -1, rrecs);
2110 xfs_btree_shift_ptrs(cur,
2111 xfs_btree_ptr_addr(cur, 2, right),
2112 -1, rrecs);
2113
2114 xfs_btree_log_keys(cur, rbp, 1, rrecs);
2115 xfs_btree_log_ptrs(cur, rbp, 1, rrecs);
2116 } else {
2117 /* It's a leaf. operate on records */
2118 xfs_btree_shift_recs(cur,
2119 xfs_btree_rec_addr(cur, 2, right),
2120 -1, rrecs);
2121 xfs_btree_log_recs(cur, rbp, 1, rrecs);
2122
2123 /*
2124 * If it's the first record in the block, we'll need a key
2125 * structure to pass up to the next level (updkey).
2126 */
2127 cur->bc_ops->init_key_from_rec(&key,
2128 xfs_btree_rec_addr(cur, 1, right));
2129 rkp = &key;
2130 }
2131
2132 /* Update the parent key values of right. */
2133 error = xfs_btree_updkey(cur, rkp, level + 1);
2134 if (error)
2135 goto error0;
2136
2137 /* Slide the cursor value left one. */
2138 cur->bc_ptrs[level]--;
2139
2140 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2141 *stat = 1;
2142 return 0;
2143
2144out0:
2145 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2146 *stat = 0;
2147 return 0;
2148
2149error0:
2150 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2151 return error;
2152}
2153
9eaead51
CH		 2154/*
2155 * Move 1 record right from cur/level if possible.
2156 * Update cur to reflect the new path.
2157 */
3cc7524c 2158STATIC int /* error */
9eaead51
CH		 2159xfs_btree_rshift(
2160 struct xfs_btree_cur *cur,
2161 int level,
2162 int *stat) /* success/failure */
2163{
2164 union xfs_btree_key key; /* btree key */
2165 struct xfs_buf *lbp; /* left buffer pointer */
2166 struct xfs_btree_block *left; /* left btree block */
2167 struct xfs_buf *rbp; /* right buffer pointer */
2168 struct xfs_btree_block *right; /* right btree block */
2169 struct xfs_btree_cur *tcur; /* temporary btree cursor */
2170 union xfs_btree_ptr rptr; /* right block pointer */
2171 union xfs_btree_key *rkp; /* right btree key */
2172 int rrecs; /* right record count */
2173 int lrecs; /* left record count */
2174 int error; /* error return value */
2175 int i; /* loop counter */
2176
2177 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2178 XFS_BTREE_TRACE_ARGI(cur, level);
2179
2180 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
2181 (level == cur->bc_nlevels - 1))
2182 goto out0;
2183
2184 /* Set up variables for this block as "left". */
2185 left = xfs_btree_get_block(cur, level, &lbp);
2186
2187#ifdef DEBUG
2188 error = xfs_btree_check_block(cur, left, level, lbp);
2189 if (error)
2190 goto error0;
2191#endif
2192
2193 /* If we've got no right sibling then we can't shift an entry right. */
2194 xfs_btree_get_sibling(cur, left, &rptr, XFS_BB_RIGHTSIB);
2195 if (xfs_btree_ptr_is_null(cur, &rptr))
2196 goto out0;
2197
2198 /*
2199 * If the cursor entry is the one that would be moved, don't
2200 * do it... it's too complicated.
2201 */
2202 lrecs = xfs_btree_get_numrecs(left);
2203 if (cur->bc_ptrs[level] >= lrecs)
2204 goto out0;
2205
2206 /* Set up the right neighbor as "right". */
2207 error = xfs_btree_read_buf_block(cur, &rptr, level, 0, &right, &rbp);
2208 if (error)
2209 goto error0;
2210
2211 /* If it's full, it can't take another entry. */
2212 rrecs = xfs_btree_get_numrecs(right);
2213 if (rrecs == cur->bc_ops->get_maxrecs(cur, level))
2214 goto out0;
2215
2216 XFS_BTREE_STATS_INC(cur, rshift);
2217 XFS_BTREE_STATS_ADD(cur, moves, rrecs);
2218
2219 /*
2220 * Make a hole at the start of the right neighbor block, then
2221 * copy the last left block entry to the hole.
2222 */
2223 if (level > 0) {
2224 /* It's a nonleaf. make a hole in the keys and ptrs */
2225 union xfs_btree_key *lkp;
2226 union xfs_btree_ptr *lpp;
2227 union xfs_btree_ptr *rpp;
2228
2229 lkp = xfs_btree_key_addr(cur, lrecs, left);
2230 lpp = xfs_btree_ptr_addr(cur, lrecs, left);
2231 rkp = xfs_btree_key_addr(cur, 1, right);
2232 rpp = xfs_btree_ptr_addr(cur, 1, right);
2233
2234#ifdef DEBUG
2235 for (i = rrecs - 1; i >= 0; i--) {
2236 error = xfs_btree_check_ptr(cur, rpp, i, level);
2237 if (error)
2238 goto error0;
2239 }
2240#endif
2241
2242 xfs_btree_shift_keys(cur, rkp, 1, rrecs);
2243 xfs_btree_shift_ptrs(cur, rpp, 1, rrecs);
2244
2245#ifdef DEBUG
2246 error = xfs_btree_check_ptr(cur, lpp, 0, level);
2247 if (error)
2248 goto error0;
2249#endif
2250
2251 /* Now put the new data in, and log it. */
2252 xfs_btree_copy_keys(cur, rkp, lkp, 1);
2253 xfs_btree_copy_ptrs(cur, rpp, lpp, 1);
2254
2255 xfs_btree_log_keys(cur, rbp, 1, rrecs + 1);
2256 xfs_btree_log_ptrs(cur, rbp, 1, rrecs + 1);
2257
4a26e66e
CH		 2258 ASSERT(cur->bc_ops->keys_inorder(cur, rkp,
2259 xfs_btree_key_addr(cur, 2, right)));
9eaead51
CH		 2260 } else {
2261 /* It's a leaf. make a hole in the records */
2262 union xfs_btree_rec *lrp;
2263 union xfs_btree_rec *rrp;
2264
2265 lrp = xfs_btree_rec_addr(cur, lrecs, left);
2266 rrp = xfs_btree_rec_addr(cur, 1, right);
2267
2268 xfs_btree_shift_recs(cur, rrp, 1, rrecs);
2269
2270 /* Now put the new data in, and log it. */
2271 xfs_btree_copy_recs(cur, rrp, lrp, 1);
2272 xfs_btree_log_recs(cur, rbp, 1, rrecs + 1);
2273
2274 cur->bc_ops->init_key_from_rec(&key, rrp);
2275 rkp = &key;
2276
4a26e66e
CH		 2277 ASSERT(cur->bc_ops->recs_inorder(cur, rrp,
2278 xfs_btree_rec_addr(cur, 2, right)));
9eaead51
CH		 2279 }
2280
2281 /*
2282 * Decrement and log left's numrecs, bump and log right's numrecs.
2283 */
2284 xfs_btree_set_numrecs(left, --lrecs);
2285 xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS);
2286
2287 xfs_btree_set_numrecs(right, ++rrecs);
2288 xfs_btree_log_block(cur, rbp, XFS_BB_NUMRECS);
2289
2290 /*
2291 * Using a temporary cursor, update the parent key values of the
2292 * block on the right.
2293 */
2294 error = xfs_btree_dup_cursor(cur, &tcur);
2295 if (error)
2296 goto error0;
2297 i = xfs_btree_lastrec(tcur, level);
2298 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
2299
2300 error = xfs_btree_increment(tcur, level, &i);
2301 if (error)
2302 goto error1;
2303
2304 error = xfs_btree_updkey(tcur, rkp, level + 1);
2305 if (error)
2306 goto error1;
2307
2308 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
2309
2310 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2311 *stat = 1;
2312 return 0;
2313
2314out0:
2315 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2316 *stat = 0;
2317 return 0;
2318
2319error0:
2320 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2321 return error;
2322
2323error1:
2324 XFS_BTREE_TRACE_CURSOR(tcur, XBT_ERROR);
2325 xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
2326 return error;
2327}
f5eb8e7c
CH		 2328
2329/*
2330 * Split cur/level block in half.
2331 * Return new block number and the key to its first
2332 * record (to be inserted into parent).
2333 */
3cc7524c 2334STATIC int /* error */
f5eb8e7c
CH		 2335xfs_btree_split(
2336 struct xfs_btree_cur *cur,
2337 int level,
2338 union xfs_btree_ptr *ptrp,
2339 union xfs_btree_key *key,
2340 struct xfs_btree_cur **curp,
2341 int *stat) /* success/failure */
2342{
2343 union xfs_btree_ptr lptr; /* left sibling block ptr */
2344 struct xfs_buf *lbp; /* left buffer pointer */
2345 struct xfs_btree_block *left; /* left btree block */
2346 union xfs_btree_ptr rptr; /* right sibling block ptr */
2347 struct xfs_buf *rbp; /* right buffer pointer */
2348 struct xfs_btree_block *right; /* right btree block */
2349 union xfs_btree_ptr rrptr; /* right-right sibling ptr */
2350 struct xfs_buf *rrbp; /* right-right buffer pointer */
2351 struct xfs_btree_block *rrblock; /* right-right btree block */
2352 int lrecs;
2353 int rrecs;
2354 int src_index;
2355 int error; /* error return value */
2356#ifdef DEBUG
2357 int i;
2358#endif
2359
2360 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2361 XFS_BTREE_TRACE_ARGIPK(cur, level, *ptrp, key);
2362
2363 XFS_BTREE_STATS_INC(cur, split);
2364
2365 /* Set up left block (current one). */
2366 left = xfs_btree_get_block(cur, level, &lbp);
2367
2368#ifdef DEBUG
2369 error = xfs_btree_check_block(cur, left, level, lbp);
2370 if (error)
2371 goto error0;
2372#endif
2373
2374 xfs_btree_buf_to_ptr(cur, lbp, &lptr);
2375
2376 /* Allocate the new block. If we can't do it, we're toast. Give up. */
2377 error = cur->bc_ops->alloc_block(cur, &lptr, &rptr, 1, stat);
2378 if (error)
2379 goto error0;
2380 if (*stat == 0)
2381 goto out0;
2382 XFS_BTREE_STATS_INC(cur, alloc);
2383
2384 /* Set up the new block as "right". */
2385 error = xfs_btree_get_buf_block(cur, &rptr, 0, &right, &rbp);
2386 if (error)
2387 goto error0;
2388
2389 /* Fill in the btree header for the new right block. */
ee1a47ab 2390 xfs_btree_init_block_cur(cur, rbp, xfs_btree_get_level(left), 0);
f5eb8e7c
CH		 2391
2392 /*
2393 * Split the entries between the old and the new block evenly.
2394 * Make sure that if there's an odd number of entries now, that
2395 * each new block will have the same number of entries.
2396 */
2397 lrecs = xfs_btree_get_numrecs(left);
2398 rrecs = lrecs / 2;
2399 if ((lrecs & 1) && cur->bc_ptrs[level] <= rrecs + 1)
2400 rrecs++;
2401 src_index = (lrecs - rrecs + 1);
2402
2403 XFS_BTREE_STATS_ADD(cur, moves, rrecs);
2404
2405 /*
2406 * Copy btree block entries from the left block over to the
2407 * new block, the right. Update the right block and log the
2408 * changes.
2409 */
2410 if (level > 0) {
2411 /* It's a non-leaf. Move keys and pointers. */
2412 union xfs_btree_key *lkp; /* left btree key */
2413 union xfs_btree_ptr *lpp; /* left address pointer */
2414 union xfs_btree_key *rkp; /* right btree key */
2415 union xfs_btree_ptr *rpp; /* right address pointer */
2416
2417 lkp = xfs_btree_key_addr(cur, src_index, left);
2418 lpp = xfs_btree_ptr_addr(cur, src_index, left);
2419 rkp = xfs_btree_key_addr(cur, 1, right);
2420 rpp = xfs_btree_ptr_addr(cur, 1, right);
2421
2422#ifdef DEBUG
2423 for (i = src_index; i < rrecs; i++) {
2424 error = xfs_btree_check_ptr(cur, lpp, i, level);
2425 if (error)
2426 goto error0;
2427 }
2428#endif
2429
2430 xfs_btree_copy_keys(cur, rkp, lkp, rrecs);
2431 xfs_btree_copy_ptrs(cur, rpp, lpp, rrecs);
2432
2433 xfs_btree_log_keys(cur, rbp, 1, rrecs);
2434 xfs_btree_log_ptrs(cur, rbp, 1, rrecs);
2435
2436 /* Grab the keys to the entries moved to the right block */
2437 xfs_btree_copy_keys(cur, key, rkp, 1);
2438 } else {
2439 /* It's a leaf. Move records. */
2440 union xfs_btree_rec *lrp; /* left record pointer */
2441 union xfs_btree_rec *rrp; /* right record pointer */
2442
2443 lrp = xfs_btree_rec_addr(cur, src_index, left);
2444 rrp = xfs_btree_rec_addr(cur, 1, right);
2445
2446 xfs_btree_copy_recs(cur, rrp, lrp, rrecs);
2447 xfs_btree_log_recs(cur, rbp, 1, rrecs);
2448
2449 cur->bc_ops->init_key_from_rec(key,
2450 xfs_btree_rec_addr(cur, 1, right));
2451 }
2452
2453
2454 /*
2455 * Find the left block number by looking in the buffer.
2456 * Adjust numrecs, sibling pointers.
2457 */
2458 xfs_btree_get_sibling(cur, left, &rrptr, XFS_BB_RIGHTSIB);
2459 xfs_btree_set_sibling(cur, right, &rrptr, XFS_BB_RIGHTSIB);
2460 xfs_btree_set_sibling(cur, right, &lptr, XFS_BB_LEFTSIB);
2461 xfs_btree_set_sibling(cur, left, &rptr, XFS_BB_RIGHTSIB);
2462
2463 lrecs -= rrecs;
2464 xfs_btree_set_numrecs(left, lrecs);
2465 xfs_btree_set_numrecs(right, xfs_btree_get_numrecs(right) + rrecs);
2466
2467 xfs_btree_log_block(cur, rbp, XFS_BB_ALL_BITS);
2468 xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS | XFS_BB_RIGHTSIB);
2469
2470 /*
2471 * If there's a block to the new block's right, make that block
2472 * point back to right instead of to left.
2473 */
2474 if (!xfs_btree_ptr_is_null(cur, &rrptr)) {
2475 error = xfs_btree_read_buf_block(cur, &rrptr, level,
2476 0, &rrblock, &rrbp);
2477 if (error)
2478 goto error0;
2479 xfs_btree_set_sibling(cur, rrblock, &rptr, XFS_BB_LEFTSIB);
2480 xfs_btree_log_block(cur, rrbp, XFS_BB_LEFTSIB);
2481 }
2482 /*
2483 * If the cursor is really in the right block, move it there.
2484 * If it's just pointing past the last entry in left, then we'll
2485 * insert there, so don't change anything in that case.
2486 */
2487 if (cur->bc_ptrs[level] > lrecs + 1) {
2488 xfs_btree_setbuf(cur, level, rbp);
2489 cur->bc_ptrs[level] -= lrecs;
2490 }
2491 /*
2492 * If there are more levels, we'll need another cursor which refers
2493 * the right block, no matter where this cursor was.
2494 */
2495 if (level + 1 < cur->bc_nlevels) {
2496 error = xfs_btree_dup_cursor(cur, curp);
2497 if (error)
2498 goto error0;
2499 (*curp)->bc_ptrs[level + 1]++;
2500 }
2501 *ptrp = rptr;
2502 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2503 *stat = 1;
2504 return 0;
2505out0:
2506 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2507 *stat = 0;
2508 return 0;
2509
2510error0:
2511 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2512 return error;
2513}
344207ce 2514
ea77b0a6
CH		 2515/*
2516 * Copy the old inode root contents into a real block and make the
2517 * broot point to it.
2518 */
2519int /* error */
2520xfs_btree_new_iroot(
2521 struct xfs_btree_cur *cur, /* btree cursor */
2522 int *logflags, /* logging flags for inode */
2523 int *stat) /* return status - 0 fail */
2524{
2525 struct xfs_buf *cbp; /* buffer for cblock */
2526 struct xfs_btree_block *block; /* btree block */
2527 struct xfs_btree_block *cblock; /* child btree block */
2528 union xfs_btree_key *ckp; /* child key pointer */
2529 union xfs_btree_ptr *cpp; /* child ptr pointer */
2530 union xfs_btree_key *kp; /* pointer to btree key */
2531 union xfs_btree_ptr *pp; /* pointer to block addr */
2532 union xfs_btree_ptr nptr; /* new block addr */
2533 int level; /* btree level */
2534 int error; /* error return code */
2535#ifdef DEBUG
2536 int i; /* loop counter */
2537#endif
2538
2539 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2540 XFS_BTREE_STATS_INC(cur, newroot);
2541
2542 ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE);
2543
2544 level = cur->bc_nlevels - 1;
2545
2546 block = xfs_btree_get_iroot(cur);
2547 pp = xfs_btree_ptr_addr(cur, 1, block);
2548
2549 /* Allocate the new block. If we can't do it, we're toast. Give up. */
2550 error = cur->bc_ops->alloc_block(cur, pp, &nptr, 1, stat);
2551 if (error)
2552 goto error0;
2553 if (*stat == 0) {
2554 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2555 return 0;
2556 }
2557 XFS_BTREE_STATS_INC(cur, alloc);
2558
2559 /* Copy the root into a real block. */
2560 error = xfs_btree_get_buf_block(cur, &nptr, 0, &cblock, &cbp);
2561 if (error)
2562 goto error0;
2563
088c9f67
DC		 2564 /*
2565 * we can't just memcpy() the root in for CRC enabled btree blocks.
2566 * In that case have to also ensure the blkno remains correct
2567 */
ea77b0a6 2568 memcpy(cblock, block, xfs_btree_block_len(cur));
088c9f67
DC		 2569 if (cur->bc_flags & XFS_BTREE_CRC_BLOCKS) {
2570 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
2571 cblock->bb_u.l.bb_blkno = cpu_to_be64(cbp->b_bn);
2572 else
2573 cblock->bb_u.s.bb_blkno = cpu_to_be64(cbp->b_bn);
2574 }
ea77b0a6
CH		 2575
2576 be16_add_cpu(&block->bb_level, 1);
2577 xfs_btree_set_numrecs(block, 1);
2578 cur->bc_nlevels++;
2579 cur->bc_ptrs[level + 1] = 1;
2580
2581 kp = xfs_btree_key_addr(cur, 1, block);
2582 ckp = xfs_btree_key_addr(cur, 1, cblock);
2583 xfs_btree_copy_keys(cur, ckp, kp, xfs_btree_get_numrecs(cblock));
2584
2585 cpp = xfs_btree_ptr_addr(cur, 1, cblock);
2586#ifdef DEBUG
2587 for (i = 0; i < be16_to_cpu(cblock->bb_numrecs); i++) {
2588 error = xfs_btree_check_ptr(cur, pp, i, level);
2589 if (error)
2590 goto error0;
2591 }
2592#endif
2593 xfs_btree_copy_ptrs(cur, cpp, pp, xfs_btree_get_numrecs(cblock));
2594
2595#ifdef DEBUG
2596 error = xfs_btree_check_ptr(cur, &nptr, 0, level);
2597 if (error)
2598 goto error0;
2599#endif
2600 xfs_btree_copy_ptrs(cur, pp, &nptr, 1);
2601
2602 xfs_iroot_realloc(cur->bc_private.b.ip,
2603 1 - xfs_btree_get_numrecs(cblock),
2604 cur->bc_private.b.whichfork);
2605
2606 xfs_btree_setbuf(cur, level, cbp);
2607
2608 /*
2609 * Do all this logging at the end so that
2610 * the root is at the right level.
2611 */
2612 xfs_btree_log_block(cur, cbp, XFS_BB_ALL_BITS);
2613 xfs_btree_log_keys(cur, cbp, 1, be16_to_cpu(cblock->bb_numrecs));
2614 xfs_btree_log_ptrs(cur, cbp, 1, be16_to_cpu(cblock->bb_numrecs));
2615
2616 *logflags |=
9d87c319 2617 XFS_ILOG_CORE | xfs_ilog_fbroot(cur->bc_private.b.whichfork);
ea77b0a6
CH		 2618 *stat = 1;
2619 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2620 return 0;
2621error0:
2622 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2623 return error;
2624}
2625
344207ce
CH		 2626/*
2627 * Allocate a new root block, fill it in.
2628 */
3cc7524c 2629STATIC int /* error */
344207ce
CH		 2630xfs_btree_new_root(
2631 struct xfs_btree_cur *cur, /* btree cursor */
2632 int *stat) /* success/failure */
2633{
2634 struct xfs_btree_block *block; /* one half of the old root block */
2635 struct xfs_buf *bp; /* buffer containing block */
2636 int error; /* error return value */
2637 struct xfs_buf *lbp; /* left buffer pointer */
2638 struct xfs_btree_block *left; /* left btree block */
2639 struct xfs_buf *nbp; /* new (root) buffer */
2640 struct xfs_btree_block *new; /* new (root) btree block */
2641 int nptr; /* new value for key index, 1 or 2 */
2642 struct xfs_buf *rbp; /* right buffer pointer */
2643 struct xfs_btree_block *right; /* right btree block */
2644 union xfs_btree_ptr rptr;
2645 union xfs_btree_ptr lptr;
2646
2647 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2648 XFS_BTREE_STATS_INC(cur, newroot);
2649
2650 /* initialise our start point from the cursor */
2651 cur->bc_ops->init_ptr_from_cur(cur, &rptr);
2652
2653 /* Allocate the new block. If we can't do it, we're toast. Give up. */
2654 error = cur->bc_ops->alloc_block(cur, &rptr, &lptr, 1, stat);
2655 if (error)
2656 goto error0;
2657 if (*stat == 0)
2658 goto out0;
2659 XFS_BTREE_STATS_INC(cur, alloc);
2660
2661 /* Set up the new block. */
2662 error = xfs_btree_get_buf_block(cur, &lptr, 0, &new, &nbp);
2663 if (error)
2664 goto error0;
2665
2666 /* Set the root in the holding structure increasing the level by 1. */
2667 cur->bc_ops->set_root(cur, &lptr, 1);
2668
2669 /*
2670 * At the previous root level there are now two blocks: the old root,
2671 * and the new block generated when it was split. We don't know which
2672 * one the cursor is pointing at, so we set up variables "left" and
2673 * "right" for each case.
2674 */
2675 block = xfs_btree_get_block(cur, cur->bc_nlevels - 1, &bp);
2676
2677#ifdef DEBUG
2678 error = xfs_btree_check_block(cur, block, cur->bc_nlevels - 1, bp);
2679 if (error)
2680 goto error0;
2681#endif
2682
2683 xfs_btree_get_sibling(cur, block, &rptr, XFS_BB_RIGHTSIB);
2684 if (!xfs_btree_ptr_is_null(cur, &rptr)) {
2685 /* Our block is left, pick up the right block. */
2686 lbp = bp;
2687 xfs_btree_buf_to_ptr(cur, lbp, &lptr);
2688 left = block;
2689 error = xfs_btree_read_buf_block(cur, &rptr,
2690 cur->bc_nlevels - 1, 0, &right, &rbp);
2691 if (error)
2692 goto error0;
2693 bp = rbp;
2694 nptr = 1;
2695 } else {
2696 /* Our block is right, pick up the left block. */
2697 rbp = bp;
2698 xfs_btree_buf_to_ptr(cur, rbp, &rptr);
2699 right = block;
2700 xfs_btree_get_sibling(cur, right, &lptr, XFS_BB_LEFTSIB);
2701 error = xfs_btree_read_buf_block(cur, &lptr,
2702 cur->bc_nlevels - 1, 0, &left, &lbp);
2703 if (error)
2704 goto error0;
2705 bp = lbp;
2706 nptr = 2;
2707 }
2708 /* Fill in the new block's btree header and log it. */
ee1a47ab 2709 xfs_btree_init_block_cur(cur, nbp, cur->bc_nlevels, 2);
344207ce
CH		 2710 xfs_btree_log_block(cur, nbp, XFS_BB_ALL_BITS);
2711 ASSERT(!xfs_btree_ptr_is_null(cur, &lptr) &&
2712 !xfs_btree_ptr_is_null(cur, &rptr));
2713
2714 /* Fill in the key data in the new root. */
2715 if (xfs_btree_get_level(left) > 0) {
2716 xfs_btree_copy_keys(cur,
2717 xfs_btree_key_addr(cur, 1, new),
2718 xfs_btree_key_addr(cur, 1, left), 1);
2719 xfs_btree_copy_keys(cur,
2720 xfs_btree_key_addr(cur, 2, new),
2721 xfs_btree_key_addr(cur, 1, right), 1);
2722 } else {
2723 cur->bc_ops->init_key_from_rec(
2724 xfs_btree_key_addr(cur, 1, new),
2725 xfs_btree_rec_addr(cur, 1, left));
2726 cur->bc_ops->init_key_from_rec(
2727 xfs_btree_key_addr(cur, 2, new),
2728 xfs_btree_rec_addr(cur, 1, right));
2729 }
2730 xfs_btree_log_keys(cur, nbp, 1, 2);
2731
2732 /* Fill in the pointer data in the new root. */
2733 xfs_btree_copy_ptrs(cur,
2734 xfs_btree_ptr_addr(cur, 1, new), &lptr, 1);
2735 xfs_btree_copy_ptrs(cur,
2736 xfs_btree_ptr_addr(cur, 2, new), &rptr, 1);
2737 xfs_btree_log_ptrs(cur, nbp, 1, 2);
2738
2739 /* Fix up the cursor. */
2740 xfs_btree_setbuf(cur, cur->bc_nlevels, nbp);
2741 cur->bc_ptrs[cur->bc_nlevels] = nptr;
2742 cur->bc_nlevels++;
2743 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2744 *stat = 1;
2745 return 0;
2746error0:
2747 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2748 return error;
2749out0:
2750 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2751 *stat = 0;
2752 return 0;
2753}
4b22a571
CH		 2754
2755STATIC int
2756xfs_btree_make_block_unfull(
2757 struct xfs_btree_cur *cur, /* btree cursor */
2758 int level, /* btree level */
2759 int numrecs,/* # of recs in block */
2760 int *oindex,/* old tree index */
2761 int *index, /* new tree index */
2762 union xfs_btree_ptr *nptr, /* new btree ptr */
2763 struct xfs_btree_cur **ncur, /* new btree cursor */
2764 union xfs_btree_rec *nrec, /* new record */
2765 int *stat)
2766{
2767 union xfs_btree_key key; /* new btree key value */
2768 int error = 0;
2769
2770 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
2771 level == cur->bc_nlevels - 1) {
2772 struct xfs_inode *ip = cur->bc_private.b.ip;
2773
2774 if (numrecs < cur->bc_ops->get_dmaxrecs(cur, level)) {
2775 /* A root block that can be made bigger. */
4b22a571
CH		 2776 xfs_iroot_realloc(ip, 1, cur->bc_private.b.whichfork);
2777 } else {
2778 /* A root block that needs replacing */
2779 int logflags = 0;
2780
2781 error = xfs_btree_new_iroot(cur, &logflags, stat);
2782 if (error || *stat == 0)
2783 return error;
2784
2785 xfs_trans_log_inode(cur->bc_tp, ip, logflags);
2786 }
2787
2788 return 0;
2789 }
2790
2791 /* First, try shifting an entry to the right neighbor. */
2792 error = xfs_btree_rshift(cur, level, stat);
2793 if (error || *stat)
2794 return error;
2795
2796 /* Next, try shifting an entry to the left neighbor. */
2797 error = xfs_btree_lshift(cur, level, stat);
2798 if (error)
2799 return error;
2800
2801 if (*stat) {
2802 *oindex = *index = cur->bc_ptrs[level];
2803 return 0;
2804 }
2805
2806 /*
2807 * Next, try splitting the current block in half.
2808 *
2809 * If this works we have to re-set our variables because we
2810 * could be in a different block now.
2811 */
2812 error = xfs_btree_split(cur, level, nptr, &key, ncur, stat);
2813 if (error || *stat == 0)
2814 return error;
2815
2816
2817 *index = cur->bc_ptrs[level];
2818 cur->bc_ops->init_rec_from_key(&key, nrec);
2819 return 0;
2820}
2821
2822/*
2823 * Insert one record/level. Return information to the caller
2824 * allowing the next level up to proceed if necessary.
2825 */
2826STATIC int
2827xfs_btree_insrec(
2828 struct xfs_btree_cur *cur, /* btree cursor */
2829 int level, /* level to insert record at */
2830 union xfs_btree_ptr *ptrp, /* i/o: block number inserted */
2831 union xfs_btree_rec *recp, /* i/o: record data inserted */
2832 struct xfs_btree_cur **curp, /* output: new cursor replacing cur */
2833 int *stat) /* success/failure */
2834{
2835 struct xfs_btree_block *block; /* btree block */
2836 struct xfs_buf *bp; /* buffer for block */
2837 union xfs_btree_key key; /* btree key */
2838 union xfs_btree_ptr nptr; /* new block ptr */
2839 struct xfs_btree_cur *ncur; /* new btree cursor */
2840 union xfs_btree_rec nrec; /* new record count */
2841 int optr; /* old key/record index */
2842 int ptr; /* key/record index */
2843 int numrecs;/* number of records */
2844 int error; /* error return value */
2845#ifdef DEBUG
2846 int i;
2847#endif
2848
2849 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2850 XFS_BTREE_TRACE_ARGIPR(cur, level, *ptrp, recp);
2851
2852 ncur = NULL;
2853
2854 /*
2855 * If we have an external root pointer, and we've made it to the
2856 * root level, allocate a new root block and we're done.
2857 */
2858 if (!(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
2859 (level >= cur->bc_nlevels)) {
2860 error = xfs_btree_new_root(cur, stat);
2861 xfs_btree_set_ptr_null(cur, ptrp);
2862
2863 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2864 return error;
2865 }
2866
2867 /* If we're off the left edge, return failure. */
2868 ptr = cur->bc_ptrs[level];
2869 if (ptr == 0) {
2870 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2871 *stat = 0;
2872 return 0;
2873 }
2874
2875 /* Make a key out of the record data to be inserted, and save it. */
2876 cur->bc_ops->init_key_from_rec(&key, recp);
2877
2878 optr = ptr;
2879
2880 XFS_BTREE_STATS_INC(cur, insrec);
2881
2882 /* Get pointers to the btree buffer and block. */
2883 block = xfs_btree_get_block(cur, level, &bp);
2884 numrecs = xfs_btree_get_numrecs(block);
2885
2886#ifdef DEBUG
2887 error = xfs_btree_check_block(cur, block, level, bp);
2888 if (error)
2889 goto error0;
2890
2891 /* Check that the new entry is being inserted in the right place. */
2892 if (ptr <= numrecs) {
2893 if (level == 0) {
4a26e66e
CH		 2894 ASSERT(cur->bc_ops->recs_inorder(cur, recp,
2895 xfs_btree_rec_addr(cur, ptr, block)));
4b22a571 2896 } else {
4a26e66e
CH		 2897 ASSERT(cur->bc_ops->keys_inorder(cur, &key,
2898 xfs_btree_key_addr(cur, ptr, block)));
4b22a571
CH		 2899 }
2900 }
2901#endif
2902
2903 /*
2904 * If the block is full, we can't insert the new entry until we
2905 * make the block un-full.
2906 */
2907 xfs_btree_set_ptr_null(cur, &nptr);
2908 if (numrecs == cur->bc_ops->get_maxrecs(cur, level)) {
2909 error = xfs_btree_make_block_unfull(cur, level, numrecs,
2910 &optr, &ptr, &nptr, &ncur, &nrec, stat);
2911 if (error || *stat == 0)
2912 goto error0;
2913 }
2914
2915 /*
2916 * The current block may have changed if the block was
2917 * previously full and we have just made space in it.
2918 */
2919 block = xfs_btree_get_block(cur, level, &bp);
2920 numrecs = xfs_btree_get_numrecs(block);
2921
2922#ifdef DEBUG
2923 error = xfs_btree_check_block(cur, block, level, bp);
2924 if (error)
2925 return error;
2926#endif
2927
2928 /*
2929 * At this point we know there's room for our new entry in the block
2930 * we're pointing at.
2931 */
2932 XFS_BTREE_STATS_ADD(cur, moves, numrecs - ptr + 1);
2933
2934 if (level > 0) {
2935 /* It's a nonleaf. make a hole in the keys and ptrs */
2936 union xfs_btree_key *kp;
2937 union xfs_btree_ptr *pp;
2938
2939 kp = xfs_btree_key_addr(cur, ptr, block);
2940 pp = xfs_btree_ptr_addr(cur, ptr, block);
2941
2942#ifdef DEBUG
2943 for (i = numrecs - ptr; i >= 0; i--) {
2944 error = xfs_btree_check_ptr(cur, pp, i, level);
2945 if (error)
2946 return error;
2947 }
2948#endif
2949
2950 xfs_btree_shift_keys(cur, kp, 1, numrecs - ptr + 1);
2951 xfs_btree_shift_ptrs(cur, pp, 1, numrecs - ptr + 1);
2952
2953#ifdef DEBUG
2954 error = xfs_btree_check_ptr(cur, ptrp, 0, level);
2955 if (error)
2956 goto error0;
2957#endif
2958
2959 /* Now put the new data in, bump numrecs and log it. */
2960 xfs_btree_copy_keys(cur, kp, &key, 1);
2961 xfs_btree_copy_ptrs(cur, pp, ptrp, 1);
2962 numrecs++;
2963 xfs_btree_set_numrecs(block, numrecs);
2964 xfs_btree_log_ptrs(cur, bp, ptr, numrecs);
2965 xfs_btree_log_keys(cur, bp, ptr, numrecs);
2966#ifdef DEBUG
2967 if (ptr < numrecs) {
4a26e66e
CH		 2968 ASSERT(cur->bc_ops->keys_inorder(cur, kp,
2969 xfs_btree_key_addr(cur, ptr + 1, block)));
4b22a571
CH		 2970 }
2971#endif
2972 } else {
2973 /* It's a leaf. make a hole in the records */
2974 union xfs_btree_rec *rp;
2975
2976 rp = xfs_btree_rec_addr(cur, ptr, block);
2977
2978 xfs_btree_shift_recs(cur, rp, 1, numrecs - ptr + 1);
2979
2980 /* Now put the new data in, bump numrecs and log it. */
2981 xfs_btree_copy_recs(cur, rp, recp, 1);
2982 xfs_btree_set_numrecs(block, ++numrecs);
2983 xfs_btree_log_recs(cur, bp, ptr, numrecs);
2984#ifdef DEBUG
2985 if (ptr < numrecs) {
4a26e66e
CH		 2986 ASSERT(cur->bc_ops->recs_inorder(cur, rp,
2987 xfs_btree_rec_addr(cur, ptr + 1, block)));
4b22a571
CH		 2988 }
2989#endif
2990 }
2991
2992 /* Log the new number of records in the btree header. */
2993 xfs_btree_log_block(cur, bp, XFS_BB_NUMRECS);
2994
2995 /* If we inserted at the start of a block, update the parents' keys. */
2996 if (optr == 1) {
2997 error = xfs_btree_updkey(cur, &key, level + 1);
2998 if (error)
2999 goto error0;
3000 }
3001
3002 /*
3003 * If we are tracking the last record in the tree and
3004 * we are at the far right edge of the tree, update it.
3005 */
3006 if (xfs_btree_is_lastrec(cur, block, level)) {
3007 cur->bc_ops->update_lastrec(cur, block, recp,
3008 ptr, LASTREC_INSREC);
3009 }
3010
3011 /*
3012 * Return the new block number, if any.
3013 * If there is one, give back a record value and a cursor too.
3014 */
3015 *ptrp = nptr;
3016 if (!xfs_btree_ptr_is_null(cur, &nptr)) {
3017 *recp = nrec;
3018 *curp = ncur;
3019 }
3020
3021 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3022 *stat = 1;
3023 return 0;
3024
3025error0:
3026 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3027 return error;
3028}
3029
3030/*
3031 * Insert the record at the point referenced by cur.
3032 *
3033 * A multi-level split of the tree on insert will invalidate the original
3034 * cursor. All callers of this function should assume that the cursor is
3035 * no longer valid and revalidate it.
3036 */
3037int
3038xfs_btree_insert(
3039 struct xfs_btree_cur *cur,
3040 int *stat)
3041{
3042 int error; /* error return value */
3043 int i; /* result value, 0 for failure */
3044 int level; /* current level number in btree */
3045 union xfs_btree_ptr nptr; /* new block number (split result) */
3046 struct xfs_btree_cur *ncur; /* new cursor (split result) */
3047 struct xfs_btree_cur *pcur; /* previous level's cursor */
3048 union xfs_btree_rec rec; /* record to insert */
3049
3050 level = 0;
3051 ncur = NULL;
3052 pcur = cur;
3053
3054 xfs_btree_set_ptr_null(cur, &nptr);
3055 cur->bc_ops->init_rec_from_cur(cur, &rec);
3056
3057 /*
3058 * Loop going up the tree, starting at the leaf level.
3059 * Stop when we don't get a split block, that must mean that
3060 * the insert is finished with this level.
3061 */
3062 do {
3063 /*
3064 * Insert nrec/nptr into this level of the tree.
3065 * Note if we fail, nptr will be null.
3066 */
3067 error = xfs_btree_insrec(pcur, level, &nptr, &rec, &ncur, &i);
3068 if (error) {
3069 if (pcur != cur)
3070 xfs_btree_del_cursor(pcur, XFS_BTREE_ERROR);
3071 goto error0;
3072 }
3073
3074 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
3075 level++;
3076
3077 /*
3078 * See if the cursor we just used is trash.
3079 * Can't trash the caller's cursor, but otherwise we should
3080 * if ncur is a new cursor or we're about to be done.
3081 */
3082 if (pcur != cur &&
3083 (ncur || xfs_btree_ptr_is_null(cur, &nptr))) {
3084 /* Save the state from the cursor before we trash it */
3085 if (cur->bc_ops->update_cursor)
3086 cur->bc_ops->update_cursor(pcur, cur);
3087 cur->bc_nlevels = pcur->bc_nlevels;
3088 xfs_btree_del_cursor(pcur, XFS_BTREE_NOERROR);
3089 }
3090 /* If we got a new cursor, switch to it. */
3091 if (ncur) {
3092 pcur = ncur;
3093 ncur = NULL;
3094 }
3095 } while (!xfs_btree_ptr_is_null(cur, &nptr));
3096
3097 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3098 *stat = i;
3099 return 0;
3100error0:
3101 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3102 return error;
3103}
d4b3a4b7
CH		 3104
3105/*
3106 * Try to merge a non-leaf block back into the inode root.
3107 *
3108 * Note: the killroot names comes from the fact that we're effectively
3109 * killing the old root block. But because we can't just delete the
3110 * inode we have to copy the single block it was pointing to into the
3111 * inode.
3112 */
d96f8f89 3113STATIC int
d4b3a4b7
CH		 3114xfs_btree_kill_iroot(
3115 struct xfs_btree_cur *cur)
3116{
3117 int whichfork = cur->bc_private.b.whichfork;
3118 struct xfs_inode *ip = cur->bc_private.b.ip;
3119 struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, whichfork);
3120 struct xfs_btree_block *block;
3121 struct xfs_btree_block *cblock;
3122 union xfs_btree_key *kp;
3123 union xfs_btree_key *ckp;
3124 union xfs_btree_ptr *pp;
3125 union xfs_btree_ptr *cpp;
3126 struct xfs_buf *cbp;
3127 int level;
3128 int index;
3129 int numrecs;
3130#ifdef DEBUG
3131 union xfs_btree_ptr ptr;
3132 int i;
3133#endif
3134
3135 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
3136
3137 ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE);
3138 ASSERT(cur->bc_nlevels > 1);
3139
3140 /*
3141 * Don't deal with the root block needs to be a leaf case.
3142 * We're just going to turn the thing back into extents anyway.
3143 */
3144 level = cur->bc_nlevels - 1;
3145 if (level == 1)
3146 goto out0;
3147
3148 /*
3149 * Give up if the root has multiple children.
3150 */
3151 block = xfs_btree_get_iroot(cur);
3152 if (xfs_btree_get_numrecs(block) != 1)
3153 goto out0;
3154
3155 cblock = xfs_btree_get_block(cur, level - 1, &cbp);
3156 numrecs = xfs_btree_get_numrecs(cblock);
3157
3158 /*
3159 * Only do this if the next level will fit.
3160 * Then the data must be copied up to the inode,
3161 * instead of freeing the root you free the next level.
3162 */
3163 if (numrecs > cur->bc_ops->get_dmaxrecs(cur, level))
3164 goto out0;
3165
3166 XFS_BTREE_STATS_INC(cur, killroot);
3167
3168#ifdef DEBUG
3169 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_LEFTSIB);
3170 ASSERT(xfs_btree_ptr_is_null(cur, &ptr));
3171 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
3172 ASSERT(xfs_btree_ptr_is_null(cur, &ptr));
3173#endif
3174
3175 index = numrecs - cur->bc_ops->get_maxrecs(cur, level);
3176 if (index) {
3177 xfs_iroot_realloc(cur->bc_private.b.ip, index,
3178 cur->bc_private.b.whichfork);
7cc95a82 3179 block = ifp->if_broot;
d4b3a4b7
CH		 3180 }
3181
3182 be16_add_cpu(&block->bb_numrecs, index);
3183 ASSERT(block->bb_numrecs == cblock->bb_numrecs);
3184
3185 kp = xfs_btree_key_addr(cur, 1, block);
3186 ckp = xfs_btree_key_addr(cur, 1, cblock);
3187 xfs_btree_copy_keys(cur, kp, ckp, numrecs);
3188
3189 pp = xfs_btree_ptr_addr(cur, 1, block);
3190 cpp = xfs_btree_ptr_addr(cur, 1, cblock);
3191#ifdef DEBUG
3192 for (i = 0; i < numrecs; i++) {
3193 int error;
3194
3195 error = xfs_btree_check_ptr(cur, cpp, i, level - 1);
3196 if (error) {
3197 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3198 return error;
3199 }
3200 }
3201#endif
3202 xfs_btree_copy_ptrs(cur, pp, cpp, numrecs);
3203
3204 cur->bc_ops->free_block(cur, cbp);
3205 XFS_BTREE_STATS_INC(cur, free);
3206
3207 cur->bc_bufs[level - 1] = NULL;
3208 be16_add_cpu(&block->bb_level, -1);
3209 xfs_trans_log_inode(cur->bc_tp, ip,
9d87c319 3210 XFS_ILOG_CORE | xfs_ilog_fbroot(cur->bc_private.b.whichfork));
d4b3a4b7
CH		 3211 cur->bc_nlevels--;
3212out0:
3213 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3214 return 0;
3215}
91cca5df 3216
c0e59e1a
CH		 3217/*
3218 * Kill the current root node, and replace it with it's only child node.
3219 */
3220STATIC int
3221xfs_btree_kill_root(
3222 struct xfs_btree_cur *cur,
3223 struct xfs_buf *bp,
3224 int level,
3225 union xfs_btree_ptr *newroot)
3226{
3227 int error;
3228
3229 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
3230 XFS_BTREE_STATS_INC(cur, killroot);
3231
3232 /*
3233 * Update the root pointer, decreasing the level by 1 and then
3234 * free the old root.
3235 */
3236 cur->bc_ops->set_root(cur, newroot, -1);
3237
3238 error = cur->bc_ops->free_block(cur, bp);
3239 if (error) {
3240 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3241 return error;
3242 }
3243
3244 XFS_BTREE_STATS_INC(cur, free);
3245
3246 cur->bc_bufs[level] = NULL;
3247 cur->bc_ra[level] = 0;
3248 cur->bc_nlevels--;
3249
3250 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3251 return 0;
3252}
3253
91cca5df
CH		 3254STATIC int
3255xfs_btree_dec_cursor(
3256 struct xfs_btree_cur *cur,
3257 int level,
3258 int *stat)
3259{
3260 int error;
3261 int i;
3262
3263 if (level > 0) {
3264 error = xfs_btree_decrement(cur, level, &i);
3265 if (error)
3266 return error;
3267 }
3268
3269 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3270 *stat = 1;
3271 return 0;
3272}
3273
3274/*
3275 * Single level of the btree record deletion routine.
3276 * Delete record pointed to by cur/level.
3277 * Remove the record from its block then rebalance the tree.
3278 * Return 0 for error, 1 for done, 2 to go on to the next level.
3279 */
3280STATIC int /* error */
3281xfs_btree_delrec(
3282 struct xfs_btree_cur *cur, /* btree cursor */
3283 int level, /* level removing record from */
3284 int *stat) /* fail/done/go-on */
3285{
3286 struct xfs_btree_block *block; /* btree block */
3287 union xfs_btree_ptr cptr; /* current block ptr */
3288 struct xfs_buf *bp; /* buffer for block */
3289 int error; /* error return value */
3290 int i; /* loop counter */
3291 union xfs_btree_key key; /* storage for keyp */
3292 union xfs_btree_key *keyp = &key; /* passed to the next level */
3293 union xfs_btree_ptr lptr; /* left sibling block ptr */
3294 struct xfs_buf *lbp; /* left buffer pointer */
3295 struct xfs_btree_block *left; /* left btree block */
3296 int lrecs = 0; /* left record count */
3297 int ptr; /* key/record index */
3298 union xfs_btree_ptr rptr; /* right sibling block ptr */
3299 struct xfs_buf *rbp; /* right buffer pointer */
3300 struct xfs_btree_block *right; /* right btree block */
3301 struct xfs_btree_block *rrblock; /* right-right btree block */
3302 struct xfs_buf *rrbp; /* right-right buffer pointer */
3303 int rrecs = 0; /* right record count */
3304 struct xfs_btree_cur *tcur; /* temporary btree cursor */
3305 int numrecs; /* temporary numrec count */
3306
3307 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
3308 XFS_BTREE_TRACE_ARGI(cur, level);
3309
3310 tcur = NULL;
3311
3312 /* Get the index of the entry being deleted, check for nothing there. */
3313 ptr = cur->bc_ptrs[level];
3314 if (ptr == 0) {
3315 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3316 *stat = 0;
3317 return 0;
3318 }
3319
3320 /* Get the buffer & block containing the record or key/ptr. */
3321 block = xfs_btree_get_block(cur, level, &bp);
3322 numrecs = xfs_btree_get_numrecs(block);
3323
3324#ifdef DEBUG
3325 error = xfs_btree_check_block(cur, block, level, bp);
3326 if (error)
3327 goto error0;
3328#endif
3329
3330 /* Fail if we're off the end of the block. */
3331 if (ptr > numrecs) {
3332 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3333 *stat = 0;
3334 return 0;
3335 }
3336
3337 XFS_BTREE_STATS_INC(cur, delrec);
3338 XFS_BTREE_STATS_ADD(cur, moves, numrecs - ptr);
3339
3340 /* Excise the entries being deleted. */
3341 if (level > 0) {
3342 /* It's a nonleaf. operate on keys and ptrs */
3343 union xfs_btree_key *lkp;
3344 union xfs_btree_ptr *lpp;
3345
3346 lkp = xfs_btree_key_addr(cur, ptr + 1, block);
3347 lpp = xfs_btree_ptr_addr(cur, ptr + 1, block);
3348
3349#ifdef DEBUG
3350 for (i = 0; i < numrecs - ptr; i++) {
3351 error = xfs_btree_check_ptr(cur, lpp, i, level);
3352 if (error)
3353 goto error0;
3354 }
3355#endif
3356
3357 if (ptr < numrecs) {
3358 xfs_btree_shift_keys(cur, lkp, -1, numrecs - ptr);
3359 xfs_btree_shift_ptrs(cur, lpp, -1, numrecs - ptr);
3360 xfs_btree_log_keys(cur, bp, ptr, numrecs - 1);
3361 xfs_btree_log_ptrs(cur, bp, ptr, numrecs - 1);
3362 }
3363
3364 /*
3365 * If it's the first record in the block, we'll need to pass a
3366 * key up to the next level (updkey).
3367 */
3368 if (ptr == 1)
3369 keyp = xfs_btree_key_addr(cur, 1, block);
3370 } else {
3371 /* It's a leaf. operate on records */
3372 if (ptr < numrecs) {
3373 xfs_btree_shift_recs(cur,
3374 xfs_btree_rec_addr(cur, ptr + 1, block),
3375 -1, numrecs - ptr);
3376 xfs_btree_log_recs(cur, bp, ptr, numrecs - 1);
3377 }
3378
3379 /*
3380 * If it's the first record in the block, we'll need a key
3381 * structure to pass up to the next level (updkey).
3382 */
3383 if (ptr == 1) {
3384 cur->bc_ops->init_key_from_rec(&key,
3385 xfs_btree_rec_addr(cur, 1, block));
3386 keyp = &key;
3387 }
3388 }
3389
3390 /*
3391 * Decrement and log the number of entries in the block.
3392 */
3393 xfs_btree_set_numrecs(block, --numrecs);
3394 xfs_btree_log_block(cur, bp, XFS_BB_NUMRECS);
3395
3396 /*
3397 * If we are tracking the last record in the tree and
3398 * we are at the far right edge of the tree, update it.
3399 */
3400 if (xfs_btree_is_lastrec(cur, block, level)) {
3401 cur->bc_ops->update_lastrec(cur, block, NULL,
3402 ptr, LASTREC_DELREC);
3403 }
3404
3405 /*
3406 * We're at the root level. First, shrink the root block in-memory.
3407 * Try to get rid of the next level down. If we can't then there's
3408 * nothing left to do.
3409 */
3410 if (level == cur->bc_nlevels - 1) {
3411 if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) {
3412 xfs_iroot_realloc(cur->bc_private.b.ip, -1,
3413 cur->bc_private.b.whichfork);
3414
3415 error = xfs_btree_kill_iroot(cur);
3416 if (error)
3417 goto error0;
3418
3419 error = xfs_btree_dec_cursor(cur, level, stat);
3420 if (error)
3421 goto error0;
3422 *stat = 1;
3423 return 0;
3424 }
3425
3426 /*
3427 * If this is the root level, and there's only one entry left,
3428 * and it's NOT the leaf level, then we can get rid of this
3429 * level.
3430 */
3431 if (numrecs == 1 && level > 0) {
3432 union xfs_btree_ptr *pp;
3433 /*
3434 * pp is still set to the first pointer in the block.
3435 * Make it the new root of the btree.
3436 */
3437 pp = xfs_btree_ptr_addr(cur, 1, block);
c0e59e1a 3438 error = xfs_btree_kill_root(cur, bp, level, pp);
91cca5df
CH		 3439 if (error)
3440 goto error0;
3441 } else if (level > 0) {
3442 error = xfs_btree_dec_cursor(cur, level, stat);
3443 if (error)
3444 goto error0;
3445 }
3446 *stat = 1;
3447 return 0;
3448 }
3449
3450 /*
3451 * If we deleted the leftmost entry in the block, update the
3452 * key values above us in the tree.
3453 */
3454 if (ptr == 1) {
3455 error = xfs_btree_updkey(cur, keyp, level + 1);
3456 if (error)
3457 goto error0;
3458 }
3459
3460 /*
3461 * If the number of records remaining in the block is at least
3462 * the minimum, we're done.
3463 */
3464 if (numrecs >= cur->bc_ops->get_minrecs(cur, level)) {
3465 error = xfs_btree_dec_cursor(cur, level, stat);
3466 if (error)
3467 goto error0;
3468 return 0;
3469 }
3470
3471 /*
3472 * Otherwise, we have to move some records around to keep the
3473 * tree balanced. Look at the left and right sibling blocks to
3474 * see if we can re-balance by moving only one record.
3475 */
3476 xfs_btree_get_sibling(cur, block, &rptr, XFS_BB_RIGHTSIB);
3477 xfs_btree_get_sibling(cur, block, &lptr, XFS_BB_LEFTSIB);
3478
3479 if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) {
3480 /*
3481 * One child of root, need to get a chance to copy its contents
3482 * into the root and delete it. Can't go up to next level,
3483 * there's nothing to delete there.
3484 */
3485 if (xfs_btree_ptr_is_null(cur, &rptr) &&
3486 xfs_btree_ptr_is_null(cur, &lptr) &&
3487 level == cur->bc_nlevels - 2) {
3488 error = xfs_btree_kill_iroot(cur);
3489 if (!error)
3490 error = xfs_btree_dec_cursor(cur, level, stat);
3491 if (error)
3492 goto error0;
3493 return 0;
3494 }
3495 }
3496
3497 ASSERT(!xfs_btree_ptr_is_null(cur, &rptr) ||
3498 !xfs_btree_ptr_is_null(cur, &lptr));
3499
3500 /*
3501 * Duplicate the cursor so our btree manipulations here won't
3502 * disrupt the next level up.
3503 */
3504 error = xfs_btree_dup_cursor(cur, &tcur);
3505 if (error)
3506 goto error0;
3507
3508 /*
3509 * If there's a right sibling, see if it's ok to shift an entry
3510 * out of it.
3511 */
3512 if (!xfs_btree_ptr_is_null(cur, &rptr)) {
3513 /*
3514 * Move the temp cursor to the last entry in the next block.
3515 * Actually any entry but the first would suffice.
3516 */
3517 i = xfs_btree_lastrec(tcur, level);
3518 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
3519
3520 error = xfs_btree_increment(tcur, level, &i);
3521 if (error)
3522 goto error0;
3523 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
3524
3525 i = xfs_btree_lastrec(tcur, level);
3526 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
3527
3528 /* Grab a pointer to the block. */
3529 right = xfs_btree_get_block(tcur, level, &rbp);
3530#ifdef DEBUG
3531 error = xfs_btree_check_block(tcur, right, level, rbp);
3532 if (error)
3533 goto error0;
3534#endif
3535 /* Grab the current block number, for future use. */
3536 xfs_btree_get_sibling(tcur, right, &cptr, XFS_BB_LEFTSIB);
3537
3538 /*
3539 * If right block is full enough so that removing one entry
3540 * won't make it too empty, and left-shifting an entry out
3541 * of right to us works, we're done.
3542 */
3543 if (xfs_btree_get_numrecs(right) - 1 >=
3544 cur->bc_ops->get_minrecs(tcur, level)) {
3545 error = xfs_btree_lshift(tcur, level, &i);
3546 if (error)
3547 goto error0;
3548 if (i) {
3549 ASSERT(xfs_btree_get_numrecs(block) >=
3550 cur->bc_ops->get_minrecs(tcur, level));
3551
3552 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
3553 tcur = NULL;
3554
3555 error = xfs_btree_dec_cursor(cur, level, stat);
3556 if (error)
3557 goto error0;
3558 return 0;
3559 }
3560 }
3561
3562 /*
3563 * Otherwise, grab the number of records in right for
3564 * future reference, and fix up the temp cursor to point
3565 * to our block again (last record).
3566 */
3567 rrecs = xfs_btree_get_numrecs(right);
3568 if (!xfs_btree_ptr_is_null(cur, &lptr)) {
3569 i = xfs_btree_firstrec(tcur, level);
3570 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
3571
3572 error = xfs_btree_decrement(tcur, level, &i);
3573 if (error)
3574 goto error0;
3575 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
3576 }
3577 }
3578
3579 /*
3580 * If there's a left sibling, see if it's ok to shift an entry
3581 * out of it.
3582 */
3583 if (!xfs_btree_ptr_is_null(cur, &lptr)) {
3584 /*
3585 * Move the temp cursor to the first entry in the
3586 * previous block.
3587 */
3588 i = xfs_btree_firstrec(tcur, level);
3589 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
3590
3591 error = xfs_btree_decrement(tcur, level, &i);
3592 if (error)
3593 goto error0;
3594 i = xfs_btree_firstrec(tcur, level);
3595 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
3596
3597 /* Grab a pointer to the block. */
3598 left = xfs_btree_get_block(tcur, level, &lbp);
3599#ifdef DEBUG
3600 error = xfs_btree_check_block(cur, left, level, lbp);
3601 if (error)
3602 goto error0;
3603#endif
3604 /* Grab the current block number, for future use. */
3605 xfs_btree_get_sibling(tcur, left, &cptr, XFS_BB_RIGHTSIB);
3606
3607 /*
3608 * If left block is full enough so that removing one entry
3609 * won't make it too empty, and right-shifting an entry out
3610 * of left to us works, we're done.
3611 */
3612 if (xfs_btree_get_numrecs(left) - 1 >=
3613 cur->bc_ops->get_minrecs(tcur, level)) {
3614 error = xfs_btree_rshift(tcur, level, &i);
3615 if (error)
3616 goto error0;
3617 if (i) {
3618 ASSERT(xfs_btree_get_numrecs(block) >=
3619 cur->bc_ops->get_minrecs(tcur, level));
3620 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
3621 tcur = NULL;
3622 if (level == 0)
3623 cur->bc_ptrs[0]++;
3624 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3625 *stat = 1;
3626 return 0;
3627 }
3628 }
3629
3630 /*
3631 * Otherwise, grab the number of records in right for
3632 * future reference.
3633 */
3634 lrecs = xfs_btree_get_numrecs(left);
3635 }
3636
3637 /* Delete the temp cursor, we're done with it. */
3638 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
3639 tcur = NULL;
3640
3641 /* If here, we need to do a join to keep the tree balanced. */
3642 ASSERT(!xfs_btree_ptr_is_null(cur, &cptr));
3643
3644 if (!xfs_btree_ptr_is_null(cur, &lptr) &&
3645 lrecs + xfs_btree_get_numrecs(block) <=
3646 cur->bc_ops->get_maxrecs(cur, level)) {
3647 /*
3648 * Set "right" to be the starting block,
3649 * "left" to be the left neighbor.
3650 */
3651 rptr = cptr;
3652 right = block;
3653 rbp = bp;
3654 error = xfs_btree_read_buf_block(cur, &lptr, level,
3655 0, &left, &lbp);
3656 if (error)
3657 goto error0;
3658
3659 /*
3660 * If that won't work, see if we can join with the right neighbor block.
3661 */
3662 } else if (!xfs_btree_ptr_is_null(cur, &rptr) &&
3663 rrecs + xfs_btree_get_numrecs(block) <=
3664 cur->bc_ops->get_maxrecs(cur, level)) {
3665 /*
3666 * Set "left" to be the starting block,
3667 * "right" to be the right neighbor.
3668 */
3669 lptr = cptr;
3670 left = block;
3671 lbp = bp;
3672 error = xfs_btree_read_buf_block(cur, &rptr, level,
3673 0, &right, &rbp);
3674 if (error)
3675 goto error0;
3676
3677 /*
3678 * Otherwise, we can't fix the imbalance.
3679 * Just return. This is probably a logic error, but it's not fatal.
3680 */
3681 } else {
3682 error = xfs_btree_dec_cursor(cur, level, stat);
3683 if (error)
3684 goto error0;
3685 return 0;
3686 }
3687
3688 rrecs = xfs_btree_get_numrecs(right);
3689 lrecs = xfs_btree_get_numrecs(left);
3690
3691 /*
3692 * We're now going to join "left" and "right" by moving all the stuff
3693 * in "right" to "left" and deleting "right".
3694 */
3695 XFS_BTREE_STATS_ADD(cur, moves, rrecs);
3696 if (level > 0) {
3697 /* It's a non-leaf. Move keys and pointers. */
3698 union xfs_btree_key *lkp; /* left btree key */
3699 union xfs_btree_ptr *lpp; /* left address pointer */
3700 union xfs_btree_key *rkp; /* right btree key */
3701 union xfs_btree_ptr *rpp; /* right address pointer */
3702
3703 lkp = xfs_btree_key_addr(cur, lrecs + 1, left);
3704 lpp = xfs_btree_ptr_addr(cur, lrecs + 1, left);
3705 rkp = xfs_btree_key_addr(cur, 1, right);
3706 rpp = xfs_btree_ptr_addr(cur, 1, right);
3707#ifdef DEBUG
3708 for (i = 1; i < rrecs; i++) {
3709 error = xfs_btree_check_ptr(cur, rpp, i, level);
3710 if (error)
3711 goto error0;
3712 }
3713#endif
3714 xfs_btree_copy_keys(cur, lkp, rkp, rrecs);
3715 xfs_btree_copy_ptrs(cur, lpp, rpp, rrecs);
3716
3717 xfs_btree_log_keys(cur, lbp, lrecs + 1, lrecs + rrecs);
3718 xfs_btree_log_ptrs(cur, lbp, lrecs + 1, lrecs + rrecs);
3719 } else {
3720 /* It's a leaf. Move records. */
3721 union xfs_btree_rec *lrp; /* left record pointer */
3722 union xfs_btree_rec *rrp; /* right record pointer */
3723
3724 lrp = xfs_btree_rec_addr(cur, lrecs + 1, left);
3725 rrp = xfs_btree_rec_addr(cur, 1, right);
3726
3727 xfs_btree_copy_recs(cur, lrp, rrp, rrecs);
3728 xfs_btree_log_recs(cur, lbp, lrecs + 1, lrecs + rrecs);
3729 }
3730
3731 XFS_BTREE_STATS_INC(cur, join);
3732
3733 /*
9da096fd 3734 * Fix up the number of records and right block pointer in the
91cca5df
CH		 3735 * surviving block, and log it.
3736 */
3737 xfs_btree_set_numrecs(left, lrecs + rrecs);
3738 xfs_btree_get_sibling(cur, right, &cptr, XFS_BB_RIGHTSIB),
3739 xfs_btree_set_sibling(cur, left, &cptr, XFS_BB_RIGHTSIB);
3740 xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS | XFS_BB_RIGHTSIB);
3741
3742 /* If there is a right sibling, point it to the remaining block. */
3743 xfs_btree_get_sibling(cur, left, &cptr, XFS_BB_RIGHTSIB);
3744 if (!xfs_btree_ptr_is_null(cur, &cptr)) {
3745 error = xfs_btree_read_buf_block(cur, &cptr, level,
3746 0, &rrblock, &rrbp);
3747 if (error)
3748 goto error0;
3749 xfs_btree_set_sibling(cur, rrblock, &lptr, XFS_BB_LEFTSIB);
3750 xfs_btree_log_block(cur, rrbp, XFS_BB_LEFTSIB);
3751 }
3752
3753 /* Free the deleted block. */
3754 error = cur->bc_ops->free_block(cur, rbp);
3755 if (error)
3756 goto error0;
3757 XFS_BTREE_STATS_INC(cur, free);
3758
3759 /*
3760 * If we joined with the left neighbor, set the buffer in the
3761 * cursor to the left block, and fix up the index.
3762 */
3763 if (bp != lbp) {
3764 cur->bc_bufs[level] = lbp;
3765 cur->bc_ptrs[level] += lrecs;
3766 cur->bc_ra[level] = 0;
3767 }
3768 /*
3769 * If we joined with the right neighbor and there's a level above
3770 * us, increment the cursor at that level.
3771 */
3772 else if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) ||
3773 (level + 1 < cur->bc_nlevels)) {
3774 error = xfs_btree_increment(cur, level + 1, &i);
3775 if (error)
3776 goto error0;
3777 }
3778
3779 /*
3780 * Readjust the ptr at this level if it's not a leaf, since it's
3781 * still pointing at the deletion point, which makes the cursor
3782 * inconsistent. If this makes the ptr 0, the caller fixes it up.
3783 * We can't use decrement because it would change the next level up.
3784 */
3785 if (level > 0)
3786 cur->bc_ptrs[level]--;
3787
3788 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3789 /* Return value means the next level up has something to do. */
3790 *stat = 2;
3791 return 0;
3792
3793error0:
3794 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3795 if (tcur)
3796 xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
3797 return error;
3798}
3799
3800/*
3801 * Delete the record pointed to by cur.
3802 * The cursor refers to the place where the record was (could be inserted)
3803 * when the operation returns.
3804 */
3805int /* error */
3806xfs_btree_delete(
3807 struct xfs_btree_cur *cur,
3808 int *stat) /* success/failure */
3809{
3810 int error; /* error return value */
3811 int level;
3812 int i;
3813
3814 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
3815
3816 /*
3817 * Go up the tree, starting at leaf level.
3818 *
3819 * If 2 is returned then a join was done; go to the next level.
3820 * Otherwise we are done.
3821 */
3822 for (level = 0, i = 2; i == 2; level++) {
3823 error = xfs_btree_delrec(cur, level, &i);
3824 if (error)
3825 goto error0;
3826 }
3827
3828 if (i == 0) {
3829 for (level = 1; level < cur->bc_nlevels; level++) {
3830 if (cur->bc_ptrs[level] == 0) {
3831 error = xfs_btree_decrement(cur, level, &i);
3832 if (error)
3833 goto error0;
3834 break;
3835 }
3836 }
3837 }
3838
3839 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3840 *stat = i;
3841 return 0;
3842error0:
3843 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3844 return error;
3845}
8cc938fe
CH		 3846
3847/*
3848 * Get the data from the pointed-to record.
3849 */
3850int /* error */
3851xfs_btree_get_rec(
3852 struct xfs_btree_cur *cur, /* btree cursor */
3853 union xfs_btree_rec **recp, /* output: btree record */
3854 int *stat) /* output: success/failure */
3855{
3856 struct xfs_btree_block *block; /* btree block */
3857 struct xfs_buf *bp; /* buffer pointer */
3858 int ptr; /* record number */
3859#ifdef DEBUG
3860 int error; /* error return value */
3861#endif
3862
3863 ptr = cur->bc_ptrs[0];
3864 block = xfs_btree_get_block(cur, 0, &bp);
3865
3866#ifdef DEBUG
3867 error = xfs_btree_check_block(cur, block, 0, bp);
3868 if (error)
3869 return error;
3870#endif
3871
3872 /*
3873 * Off the right end or left end, return failure.
3874 */
3875 if (ptr > xfs_btree_get_numrecs(block) || ptr <= 0) {
3876 *stat = 0;
3877 return 0;
3878 }
3879
3880 /*
3881 * Point to the record and extract its data.
3882 */
3883 *recp = xfs_btree_rec_addr(cur, ptr, block);
3884 *stat = 1;
3885 return 0;
3886}
21b5c978
DC		 3887
3888/*
3889 * Change the owner of a btree.
3890 *
3891 * The mechanism we use here is ordered buffer logging. Because we don't know
3892 * how many buffers were are going to need to modify, we don't really want to
3893 * have to make transaction reservations for the worst case of every buffer in a
3894 * full size btree as that may be more space that we can fit in the log....
3895 *
3896 * We do the btree walk in the most optimal manner possible - we have sibling
3897 * pointers so we can just walk all the blocks on each level from left to right
3898 * in a single pass, and then move to the next level and do the same. We can
3899 * also do readahead on the sibling pointers to get IO moving more quickly,
3900 * though for slow disks this is unlikely to make much difference to performance
3901 * as the amount of CPU work we have to do before moving to the next block is
3902 * relatively small.
3903 *
3904 * For each btree block that we load, modify the owner appropriately, set the
3905 * buffer as an ordered buffer and log it appropriately. We need to ensure that
3906 * we mark the region we change dirty so that if the buffer is relogged in
3907 * a subsequent transaction the changes we make here as an ordered buffer are
638f4416
DC		 3908 * correctly relogged in that transaction. If we are in recovery context, then
3909 * just queue the modified buffer as delayed write buffer so the transaction
3910 * recovery completion writes the changes to disk.
21b5c978
DC		 3911 */
3912static int
3913xfs_btree_block_change_owner(
3914 struct xfs_btree_cur *cur,
3915 int level,
638f4416
DC		 3916 __uint64_t new_owner,
3917 struct list_head *buffer_list)
21b5c978
DC		 3918{
3919 struct xfs_btree_block *block;
3920 struct xfs_buf *bp;
3921 union xfs_btree_ptr rptr;
3922
3923 /* do right sibling readahead */
3924 xfs_btree_readahead(cur, level, XFS_BTCUR_RIGHTRA);
3925
3926 /* modify the owner */
3927 block = xfs_btree_get_block(cur, level, &bp);
3928 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
3929 block->bb_u.l.bb_owner = cpu_to_be64(new_owner);
3930 else
3931 block->bb_u.s.bb_owner = cpu_to_be32(new_owner);
3932
3933 /*
638f4416
DC		 3934 * If the block is a root block hosted in an inode, we might not have a
3935 * buffer pointer here and we shouldn't attempt to log the change as the
3936 * information is already held in the inode and discarded when the root
3937 * block is formatted into the on-disk inode fork. We still change it,
3938 * though, so everything is consistent in memory.
21b5c978
DC		 3939 */
3940 if (bp) {
638f4416
DC		 3941 if (cur->bc_tp) {
3942 xfs_trans_ordered_buf(cur->bc_tp, bp);
3943 xfs_btree_log_block(cur, bp, XFS_BB_OWNER);
3944 } else {
3945 xfs_buf_delwri_queue(bp, buffer_list);
3946 }
21b5c978
DC		 3947 } else {
3948 ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE);
3949 ASSERT(level == cur->bc_nlevels - 1);
3950 }
3951
3952 /* now read rh sibling block for next iteration */
3953 xfs_btree_get_sibling(cur, block, &rptr, XFS_BB_RIGHTSIB);
3954 if (xfs_btree_ptr_is_null(cur, &rptr))
3955 return ENOENT;
3956
3957 return xfs_btree_lookup_get_block(cur, level, &rptr, &block);
3958}
3959
3960int
3961xfs_btree_change_owner(
3962 struct xfs_btree_cur *cur,
638f4416
DC		 3963 __uint64_t new_owner,
3964 struct list_head *buffer_list)
21b5c978
DC		 3965{
3966 union xfs_btree_ptr lptr;
3967 int level;
3968 struct xfs_btree_block *block = NULL;
3969 int error = 0;
3970
3971 cur->bc_ops->init_ptr_from_cur(cur, &lptr);
3972
3973 /* for each level */
3974 for (level = cur->bc_nlevels - 1; level >= 0; level--) {
3975 /* grab the left hand block */
3976 error = xfs_btree_lookup_get_block(cur, level, &lptr, &block);
3977 if (error)
3978 return error;
3979
3980 /* readahead the left most block for the next level down */
3981 if (level > 0) {
3982 union xfs_btree_ptr *ptr;
3983
3984 ptr = xfs_btree_ptr_addr(cur, 1, block);
3985 xfs_btree_readahead_ptr(cur, ptr, 1);
3986
3987 /* save for the next iteration of the loop */
3988 lptr = *ptr;
3989 }
3990
3991 /* for each buffer in the level */
3992 do {
3993 error = xfs_btree_block_change_owner(cur, level,
638f4416
DC		 3994 new_owner,
3995 buffer_list);
21b5c978
DC		 3996 } while (!error);
3997
3998 if (error != ENOENT)
3999 return error;
4000 }
4001
4002 return 0;
4003}
Linux kernel - Deliverables
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