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-rw-r--r--fs/xfs/xfs_btree.c3596
1 files changed, 3186 insertions, 410 deletions
diff --git a/fs/xfs/xfs_btree.c b/fs/xfs/xfs_btree.c
index cc593a84c345..7ed59267420d 100644
--- a/fs/xfs/xfs_btree.c
+++ b/fs/xfs/xfs_btree.c
@@ -34,7 +34,9 @@
34#include "xfs_attr_sf.h" 34#include "xfs_attr_sf.h"
35#include "xfs_dinode.h" 35#include "xfs_dinode.h"
36#include "xfs_inode.h" 36#include "xfs_inode.h"
37#include "xfs_inode_item.h"
37#include "xfs_btree.h" 38#include "xfs_btree.h"
39#include "xfs_btree_trace.h"
38#include "xfs_ialloc.h" 40#include "xfs_ialloc.h"
39#include "xfs_error.h" 41#include "xfs_error.h"
40 42
@@ -50,135 +52,33 @@ const __uint32_t xfs_magics[XFS_BTNUM_MAX] = {
50 XFS_ABTB_MAGIC, XFS_ABTC_MAGIC, XFS_BMAP_MAGIC, XFS_IBT_MAGIC 52 XFS_ABTB_MAGIC, XFS_ABTC_MAGIC, XFS_BMAP_MAGIC, XFS_IBT_MAGIC
51}; 53};
52 54
53/*
54 * Checking routine: return maxrecs for the block.
55 */
56STATIC int /* number of records fitting in block */
57xfs_btree_maxrecs(
58 xfs_btree_cur_t *cur, /* btree cursor */
59 xfs_btree_block_t *block) /* generic btree block pointer */
60{
61 switch (cur->bc_btnum) {
62 case XFS_BTNUM_BNO:
63 case XFS_BTNUM_CNT:
64 return (int)XFS_ALLOC_BLOCK_MAXRECS(
65 be16_to_cpu(block->bb_h.bb_level), cur);
66 case XFS_BTNUM_BMAP:
67 return (int)XFS_BMAP_BLOCK_IMAXRECS(
68 be16_to_cpu(block->bb_h.bb_level), cur);
69 case XFS_BTNUM_INO:
70 return (int)XFS_INOBT_BLOCK_MAXRECS(
71 be16_to_cpu(block->bb_h.bb_level), cur);
72 default:
73 ASSERT(0);
74 return 0;
75 }
76}
77
78/*
79 * External routines.
80 */
81
82#ifdef DEBUG
83/*
84 * Debug routine: check that block header is ok.
85 */
86void
87xfs_btree_check_block(
88 xfs_btree_cur_t *cur, /* btree cursor */
89 xfs_btree_block_t *block, /* generic btree block pointer */
90 int level, /* level of the btree block */
91 xfs_buf_t *bp) /* buffer containing block, if any */
92{
93 if (XFS_BTREE_LONG_PTRS(cur->bc_btnum))
94 xfs_btree_check_lblock(cur, (xfs_btree_lblock_t *)block, level,
95 bp);
96 else
97 xfs_btree_check_sblock(cur, (xfs_btree_sblock_t *)block, level,
98 bp);
99}
100
101/*
102 * Debug routine: check that keys are in the right order.
103 */
104void
105xfs_btree_check_key(
106 xfs_btnum_t btnum, /* btree identifier */
107 void *ak1, /* pointer to left (lower) key */
108 void *ak2) /* pointer to right (higher) key */
109{
110 switch (btnum) {
111 case XFS_BTNUM_BNO: {
112 xfs_alloc_key_t *k1;
113 xfs_alloc_key_t *k2;
114
115 k1 = ak1;
116 k2 = ak2;
117 ASSERT(be32_to_cpu(k1->ar_startblock) < be32_to_cpu(k2->ar_startblock));
118 break;
119 }
120 case XFS_BTNUM_CNT: {
121 xfs_alloc_key_t *k1;
122 xfs_alloc_key_t *k2;
123
124 k1 = ak1;
125 k2 = ak2;
126 ASSERT(be32_to_cpu(k1->ar_blockcount) < be32_to_cpu(k2->ar_blockcount) ||
127 (k1->ar_blockcount == k2->ar_blockcount &&
128 be32_to_cpu(k1->ar_startblock) < be32_to_cpu(k2->ar_startblock)));
129 break;
130 }
131 case XFS_BTNUM_BMAP: {
132 xfs_bmbt_key_t *k1;
133 xfs_bmbt_key_t *k2;
134
135 k1 = ak1;
136 k2 = ak2;
137 ASSERT(be64_to_cpu(k1->br_startoff) < be64_to_cpu(k2->br_startoff));
138 break;
139 }
140 case XFS_BTNUM_INO: {
141 xfs_inobt_key_t *k1;
142 xfs_inobt_key_t *k2;
143
144 k1 = ak1;
145 k2 = ak2;
146 ASSERT(be32_to_cpu(k1->ir_startino) < be32_to_cpu(k2->ir_startino));
147 break;
148 }
149 default:
150 ASSERT(0);
151 }
152}
153#endif /* DEBUG */
154 55
155/* 56STATIC int /* error (0 or EFSCORRUPTED) */
156 * Checking routine: check that long form block header is ok.
157 */
158/* ARGSUSED */
159int /* error (0 or EFSCORRUPTED) */
160xfs_btree_check_lblock( 57xfs_btree_check_lblock(
161 xfs_btree_cur_t *cur, /* btree cursor */ 58 struct xfs_btree_cur *cur, /* btree cursor */
162 xfs_btree_lblock_t *block, /* btree long form block pointer */ 59 struct xfs_btree_block *block, /* btree long form block pointer */
163 int level, /* level of the btree block */ 60 int level, /* level of the btree block */
164 xfs_buf_t *bp) /* buffer for block, if any */ 61 struct xfs_buf *bp) /* buffer for block, if any */
165{ 62{
166 int lblock_ok; /* block passes checks */ 63 int lblock_ok; /* block passes checks */
167 xfs_mount_t *mp; /* file system mount point */ 64 struct xfs_mount *mp; /* file system mount point */
168 65
169 mp = cur->bc_mp; 66 mp = cur->bc_mp;
170 lblock_ok = 67 lblock_ok =
171 be32_to_cpu(block->bb_magic) == xfs_magics[cur->bc_btnum] && 68 be32_to_cpu(block->bb_magic) == xfs_magics[cur->bc_btnum] &&
172 be16_to_cpu(block->bb_level) == level && 69 be16_to_cpu(block->bb_level) == level &&
173 be16_to_cpu(block->bb_numrecs) <= 70 be16_to_cpu(block->bb_numrecs) <=
174 xfs_btree_maxrecs(cur, (xfs_btree_block_t *)block) && 71 cur->bc_ops->get_maxrecs(cur, level) &&
175 block->bb_leftsib && 72 block->bb_u.l.bb_leftsib &&
176 (be64_to_cpu(block->bb_leftsib) == NULLDFSBNO || 73 (be64_to_cpu(block->bb_u.l.bb_leftsib) == NULLDFSBNO ||
177 XFS_FSB_SANITY_CHECK(mp, be64_to_cpu(block->bb_leftsib))) && 74 XFS_FSB_SANITY_CHECK(mp,
178 block->bb_rightsib && 75 be64_to_cpu(block->bb_u.l.bb_leftsib))) &&
179 (be64_to_cpu(block->bb_rightsib) == NULLDFSBNO || 76 block->bb_u.l.bb_rightsib &&
180 XFS_FSB_SANITY_CHECK(mp, be64_to_cpu(block->bb_rightsib))); 77 (be64_to_cpu(block->bb_u.l.bb_rightsib) == NULLDFSBNO ||
181 if (unlikely(XFS_TEST_ERROR(!lblock_ok, mp, XFS_ERRTAG_BTREE_CHECK_LBLOCK, 78 XFS_FSB_SANITY_CHECK(mp,
79 be64_to_cpu(block->bb_u.l.bb_rightsib)));
80 if (unlikely(XFS_TEST_ERROR(!lblock_ok, mp,
81 XFS_ERRTAG_BTREE_CHECK_LBLOCK,
182 XFS_RANDOM_BTREE_CHECK_LBLOCK))) { 82 XFS_RANDOM_BTREE_CHECK_LBLOCK))) {
183 if (bp) 83 if (bp)
184 xfs_buftrace("LBTREE ERROR", bp); 84 xfs_buftrace("LBTREE ERROR", bp);
@@ -189,98 +89,15 @@ xfs_btree_check_lblock(
189 return 0; 89 return 0;
190} 90}
191 91
192/* 92STATIC int /* error (0 or EFSCORRUPTED) */
193 * Checking routine: check that (long) pointer is ok.
194 */
195int /* error (0 or EFSCORRUPTED) */
196xfs_btree_check_lptr(
197 xfs_btree_cur_t *cur, /* btree cursor */
198 xfs_dfsbno_t ptr, /* btree block disk address */
199 int level) /* btree block level */
200{
201 xfs_mount_t *mp; /* file system mount point */
202
203 mp = cur->bc_mp;
204 XFS_WANT_CORRUPTED_RETURN(
205 level > 0 &&
206 ptr != NULLDFSBNO &&
207 XFS_FSB_SANITY_CHECK(mp, ptr));
208 return 0;
209}
210
211#ifdef DEBUG
212/*
213 * Debug routine: check that records are in the right order.
214 */
215void
216xfs_btree_check_rec(
217 xfs_btnum_t btnum, /* btree identifier */
218 void *ar1, /* pointer to left (lower) record */
219 void *ar2) /* pointer to right (higher) record */
220{
221 switch (btnum) {
222 case XFS_BTNUM_BNO: {
223 xfs_alloc_rec_t *r1;
224 xfs_alloc_rec_t *r2;
225
226 r1 = ar1;
227 r2 = ar2;
228 ASSERT(be32_to_cpu(r1->ar_startblock) +
229 be32_to_cpu(r1->ar_blockcount) <=
230 be32_to_cpu(r2->ar_startblock));
231 break;
232 }
233 case XFS_BTNUM_CNT: {
234 xfs_alloc_rec_t *r1;
235 xfs_alloc_rec_t *r2;
236
237 r1 = ar1;
238 r2 = ar2;
239 ASSERT(be32_to_cpu(r1->ar_blockcount) < be32_to_cpu(r2->ar_blockcount) ||
240 (r1->ar_blockcount == r2->ar_blockcount &&
241 be32_to_cpu(r1->ar_startblock) < be32_to_cpu(r2->ar_startblock)));
242 break;
243 }
244 case XFS_BTNUM_BMAP: {
245 xfs_bmbt_rec_t *r1;
246 xfs_bmbt_rec_t *r2;
247
248 r1 = ar1;
249 r2 = ar2;
250 ASSERT(xfs_bmbt_disk_get_startoff(r1) +
251 xfs_bmbt_disk_get_blockcount(r1) <=
252 xfs_bmbt_disk_get_startoff(r2));
253 break;
254 }
255 case XFS_BTNUM_INO: {
256 xfs_inobt_rec_t *r1;
257 xfs_inobt_rec_t *r2;
258
259 r1 = ar1;
260 r2 = ar2;
261 ASSERT(be32_to_cpu(r1->ir_startino) + XFS_INODES_PER_CHUNK <=
262 be32_to_cpu(r2->ir_startino));
263 break;
264 }
265 default:
266 ASSERT(0);
267 }
268}
269#endif /* DEBUG */
270
271/*
272 * Checking routine: check that block header is ok.
273 */
274/* ARGSUSED */
275int /* error (0 or EFSCORRUPTED) */
276xfs_btree_check_sblock( 93xfs_btree_check_sblock(
277 xfs_btree_cur_t *cur, /* btree cursor */ 94 struct xfs_btree_cur *cur, /* btree cursor */
278 xfs_btree_sblock_t *block, /* btree short form block pointer */ 95 struct xfs_btree_block *block, /* btree short form block pointer */
279 int level, /* level of the btree block */ 96 int level, /* level of the btree block */
280 xfs_buf_t *bp) /* buffer containing block */ 97 struct xfs_buf *bp) /* buffer containing block */
281{ 98{
282 xfs_buf_t *agbp; /* buffer for ag. freespace struct */ 99 struct xfs_buf *agbp; /* buffer for ag. freespace struct */
283 xfs_agf_t *agf; /* ag. freespace structure */ 100 struct xfs_agf *agf; /* ag. freespace structure */
284 xfs_agblock_t agflen; /* native ag. freespace length */ 101 xfs_agblock_t agflen; /* native ag. freespace length */
285 int sblock_ok; /* block passes checks */ 102 int sblock_ok; /* block passes checks */
286 103
@@ -291,13 +108,13 @@ xfs_btree_check_sblock(
291 be32_to_cpu(block->bb_magic) == xfs_magics[cur->bc_btnum] && 108 be32_to_cpu(block->bb_magic) == xfs_magics[cur->bc_btnum] &&
292 be16_to_cpu(block->bb_level) == level && 109 be16_to_cpu(block->bb_level) == level &&
293 be16_to_cpu(block->bb_numrecs) <= 110 be16_to_cpu(block->bb_numrecs) <=
294 xfs_btree_maxrecs(cur, (xfs_btree_block_t *)block) && 111 cur->bc_ops->get_maxrecs(cur, level) &&
295 (be32_to_cpu(block->bb_leftsib) == NULLAGBLOCK || 112 (be32_to_cpu(block->bb_u.s.bb_leftsib) == NULLAGBLOCK ||
296 be32_to_cpu(block->bb_leftsib) < agflen) && 113 be32_to_cpu(block->bb_u.s.bb_leftsib) < agflen) &&
297 block->bb_leftsib && 114 block->bb_u.s.bb_leftsib &&
298 (be32_to_cpu(block->bb_rightsib) == NULLAGBLOCK || 115 (be32_to_cpu(block->bb_u.s.bb_rightsib) == NULLAGBLOCK ||
299 be32_to_cpu(block->bb_rightsib) < agflen) && 116 be32_to_cpu(block->bb_u.s.bb_rightsib) < agflen) &&
300 block->bb_rightsib; 117 block->bb_u.s.bb_rightsib;
301 if (unlikely(XFS_TEST_ERROR(!sblock_ok, cur->bc_mp, 118 if (unlikely(XFS_TEST_ERROR(!sblock_ok, cur->bc_mp,
302 XFS_ERRTAG_BTREE_CHECK_SBLOCK, 119 XFS_ERRTAG_BTREE_CHECK_SBLOCK,
303 XFS_RANDOM_BTREE_CHECK_SBLOCK))) { 120 XFS_RANDOM_BTREE_CHECK_SBLOCK))) {
@@ -311,27 +128,78 @@ xfs_btree_check_sblock(
311} 128}
312 129
313/* 130/*
314 * Checking routine: check that (short) pointer is ok. 131 * Debug routine: check that block header is ok.
132 */
133int
134xfs_btree_check_block(
135 struct xfs_btree_cur *cur, /* btree cursor */
136 struct xfs_btree_block *block, /* generic btree block pointer */
137 int level, /* level of the btree block */
138 struct xfs_buf *bp) /* buffer containing block, if any */
139{
140 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
141 return xfs_btree_check_lblock(cur, block, level, bp);
142 else
143 return xfs_btree_check_sblock(cur, block, level, bp);
144}
145
146/*
147 * Check that (long) pointer is ok.
315 */ 148 */
316int /* error (0 or EFSCORRUPTED) */ 149int /* error (0 or EFSCORRUPTED) */
150xfs_btree_check_lptr(
151 struct xfs_btree_cur *cur, /* btree cursor */
152 xfs_dfsbno_t bno, /* btree block disk address */
153 int level) /* btree block level */
154{
155 XFS_WANT_CORRUPTED_RETURN(
156 level > 0 &&
157 bno != NULLDFSBNO &&
158 XFS_FSB_SANITY_CHECK(cur->bc_mp, bno));
159 return 0;
160}
161
162#ifdef DEBUG
163/*
164 * Check that (short) pointer is ok.
165 */
166STATIC int /* error (0 or EFSCORRUPTED) */
317xfs_btree_check_sptr( 167xfs_btree_check_sptr(
318 xfs_btree_cur_t *cur, /* btree cursor */ 168 struct xfs_btree_cur *cur, /* btree cursor */
319 xfs_agblock_t ptr, /* btree block disk address */ 169 xfs_agblock_t bno, /* btree block disk address */
320 int level) /* btree block level */ 170 int level) /* btree block level */
321{ 171{
322 xfs_buf_t *agbp; /* buffer for ag. freespace struct */ 172 xfs_agblock_t agblocks = cur->bc_mp->m_sb.sb_agblocks;
323 xfs_agf_t *agf; /* ag. freespace structure */
324 173
325 agbp = cur->bc_private.a.agbp;
326 agf = XFS_BUF_TO_AGF(agbp);
327 XFS_WANT_CORRUPTED_RETURN( 174 XFS_WANT_CORRUPTED_RETURN(
328 level > 0 && 175 level > 0 &&
329 ptr != NULLAGBLOCK && ptr != 0 && 176 bno != NULLAGBLOCK &&
330 ptr < be32_to_cpu(agf->agf_length)); 177 bno != 0 &&
178 bno < agblocks);
331 return 0; 179 return 0;
332} 180}
333 181
334/* 182/*
183 * Check that block ptr is ok.
184 */
185STATIC int /* error (0 or EFSCORRUPTED) */
186xfs_btree_check_ptr(
187 struct xfs_btree_cur *cur, /* btree cursor */
188 union xfs_btree_ptr *ptr, /* btree block disk address */
189 int index, /* offset from ptr to check */
190 int level) /* btree block level */
191{
192 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
193 return xfs_btree_check_lptr(cur,
194 be64_to_cpu((&ptr->l)[index]), level);
195 } else {
196 return xfs_btree_check_sptr(cur,
197 be32_to_cpu((&ptr->s)[index]), level);
198 }
199}
200#endif
201
202/*
335 * Delete the btree cursor. 203 * Delete the btree cursor.
336 */ 204 */
337void 205void
@@ -387,16 +255,17 @@ xfs_btree_dup_cursor(
387 255
388 tp = cur->bc_tp; 256 tp = cur->bc_tp;
389 mp = cur->bc_mp; 257 mp = cur->bc_mp;
258
390 /* 259 /*
391 * Allocate a new cursor like the old one. 260 * Allocate a new cursor like the old one.
392 */ 261 */
393 new = xfs_btree_init_cursor(mp, tp, cur->bc_private.a.agbp, 262 new = cur->bc_ops->dup_cursor(cur);
394 cur->bc_private.a.agno, cur->bc_btnum, cur->bc_private.b.ip, 263
395 cur->bc_private.b.whichfork);
396 /* 264 /*
397 * Copy the record currently in the cursor. 265 * Copy the record currently in the cursor.
398 */ 266 */
399 new->bc_rec = cur->bc_rec; 267 new->bc_rec = cur->bc_rec;
268
400 /* 269 /*
401 * For each level current, re-get the buffer and copy the ptr value. 270 * For each level current, re-get the buffer and copy the ptr value.
402 */ 271 */
@@ -416,46 +285,174 @@ xfs_btree_dup_cursor(
416 } else 285 } else
417 new->bc_bufs[i] = NULL; 286 new->bc_bufs[i] = NULL;
418 } 287 }
419 /*
420 * For bmap btrees, copy the firstblock, flist, and flags values,
421 * since init cursor doesn't get them.
422 */
423 if (new->bc_btnum == XFS_BTNUM_BMAP) {
424 new->bc_private.b.firstblock = cur->bc_private.b.firstblock;
425 new->bc_private.b.flist = cur->bc_private.b.flist;
426 new->bc_private.b.flags = cur->bc_private.b.flags;
427 }
428 *ncur = new; 288 *ncur = new;
429 return 0; 289 return 0;
430} 290}
431 291
432/* 292/*
293 * XFS btree block layout and addressing:
294 *
295 * There are two types of blocks in the btree: leaf and non-leaf blocks.
296 *
297 * The leaf record start with a header then followed by records containing
298 * the values. A non-leaf block also starts with the same header, and
299 * then first contains lookup keys followed by an equal number of pointers
300 * to the btree blocks at the previous level.
301 *
302 * +--------+-------+-------+-------+-------+-------+-------+
303 * Leaf: | header | rec 1 | rec 2 | rec 3 | rec 4 | rec 5 | rec N |
304 * +--------+-------+-------+-------+-------+-------+-------+
305 *
306 * +--------+-------+-------+-------+-------+-------+-------+
307 * Non-Leaf: | header | key 1 | key 2 | key N | ptr 1 | ptr 2 | ptr N |
308 * +--------+-------+-------+-------+-------+-------+-------+
309 *
310 * The header is called struct xfs_btree_block for reasons better left unknown
311 * and comes in different versions for short (32bit) and long (64bit) block
312 * pointers. The record and key structures are defined by the btree instances
313 * and opaque to the btree core. The block pointers are simple disk endian
314 * integers, available in a short (32bit) and long (64bit) variant.
315 *
316 * The helpers below calculate the offset of a given record, key or pointer
317 * into a btree block (xfs_btree_*_offset) or return a pointer to the given
318 * record, key or pointer (xfs_btree_*_addr). Note that all addressing
319 * inside the btree block is done using indices starting at one, not zero!
320 */
321
322/*
323 * Return size of the btree block header for this btree instance.
324 */
325static inline size_t xfs_btree_block_len(struct xfs_btree_cur *cur)
326{
327 return (cur->bc_flags & XFS_BTREE_LONG_PTRS) ?
328 XFS_BTREE_LBLOCK_LEN :
329 XFS_BTREE_SBLOCK_LEN;
330}
331
332/*
333 * Return size of btree block pointers for this btree instance.
334 */
335static inline size_t xfs_btree_ptr_len(struct xfs_btree_cur *cur)
336{
337 return (cur->bc_flags & XFS_BTREE_LONG_PTRS) ?
338 sizeof(__be64) : sizeof(__be32);
339}
340
341/*
342 * Calculate offset of the n-th record in a btree block.
343 */
344STATIC size_t
345xfs_btree_rec_offset(
346 struct xfs_btree_cur *cur,
347 int n)
348{
349 return xfs_btree_block_len(cur) +
350 (n - 1) * cur->bc_ops->rec_len;
351}
352
353/*
354 * Calculate offset of the n-th key in a btree block.
355 */
356STATIC size_t
357xfs_btree_key_offset(
358 struct xfs_btree_cur *cur,
359 int n)
360{
361 return xfs_btree_block_len(cur) +
362 (n - 1) * cur->bc_ops->key_len;
363}
364
365/*
366 * Calculate offset of the n-th block pointer in a btree block.
367 */
368STATIC size_t
369xfs_btree_ptr_offset(
370 struct xfs_btree_cur *cur,
371 int n,
372 int level)
373{
374 return xfs_btree_block_len(cur) +
375 cur->bc_ops->get_maxrecs(cur, level) * cur->bc_ops->key_len +
376 (n - 1) * xfs_btree_ptr_len(cur);
377}
378
379/*
380 * Return a pointer to the n-th record in the btree block.
381 */
382STATIC union xfs_btree_rec *
383xfs_btree_rec_addr(
384 struct xfs_btree_cur *cur,
385 int n,
386 struct xfs_btree_block *block)
387{
388 return (union xfs_btree_rec *)
389 ((char *)block + xfs_btree_rec_offset(cur, n));
390}
391
392/*
393 * Return a pointer to the n-th key in the btree block.
394 */
395STATIC union xfs_btree_key *
396xfs_btree_key_addr(
397 struct xfs_btree_cur *cur,
398 int n,
399 struct xfs_btree_block *block)
400{
401 return (union xfs_btree_key *)
402 ((char *)block + xfs_btree_key_offset(cur, n));
403}
404
405/*
406 * Return a pointer to the n-th block pointer in the btree block.
407 */
408STATIC union xfs_btree_ptr *
409xfs_btree_ptr_addr(
410 struct xfs_btree_cur *cur,
411 int n,
412 struct xfs_btree_block *block)
413{
414 int level = xfs_btree_get_level(block);
415
416 ASSERT(block->bb_level != 0);
417
418 return (union xfs_btree_ptr *)
419 ((char *)block + xfs_btree_ptr_offset(cur, n, level));
420}
421
422/*
423 * Get a the root block which is stored in the inode.
424 *
425 * For now this btree implementation assumes the btree root is always
426 * stored in the if_broot field of an inode fork.
427 */
428STATIC struct xfs_btree_block *
429xfs_btree_get_iroot(
430 struct xfs_btree_cur *cur)
431{
432 struct xfs_ifork *ifp;
433
434 ifp = XFS_IFORK_PTR(cur->bc_private.b.ip, cur->bc_private.b.whichfork);
435 return (struct xfs_btree_block *)ifp->if_broot;
436}
437
438/*
433 * Retrieve the block pointer from the cursor at the given level. 439 * Retrieve the block pointer from the cursor at the given level.
434 * This may be a bmap btree root or from a buffer. 440 * This may be an inode btree root or from a buffer.
435 */ 441 */
436STATIC xfs_btree_block_t * /* generic btree block pointer */ 442STATIC struct xfs_btree_block * /* generic btree block pointer */
437xfs_btree_get_block( 443xfs_btree_get_block(
438 xfs_btree_cur_t *cur, /* btree cursor */ 444 struct xfs_btree_cur *cur, /* btree cursor */
439 int level, /* level in btree */ 445 int level, /* level in btree */
440 xfs_buf_t **bpp) /* buffer containing the block */ 446 struct xfs_buf **bpp) /* buffer containing the block */
441{ 447{
442 xfs_btree_block_t *block; /* return value */ 448 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
443 xfs_buf_t *bp; /* return buffer */ 449 (level == cur->bc_nlevels - 1)) {
444 xfs_ifork_t *ifp; /* inode fork pointer */ 450 *bpp = NULL;
445 int whichfork; /* data or attr fork */ 451 return xfs_btree_get_iroot(cur);
446
447 if (cur->bc_btnum == XFS_BTNUM_BMAP && level == cur->bc_nlevels - 1) {
448 whichfork = cur->bc_private.b.whichfork;
449 ifp = XFS_IFORK_PTR(cur->bc_private.b.ip, whichfork);
450 block = (xfs_btree_block_t *)ifp->if_broot;
451 bp = NULL;
452 } else {
453 bp = cur->bc_bufs[level];
454 block = XFS_BUF_TO_BLOCK(bp);
455 } 452 }
456 ASSERT(block != NULL); 453
457 *bpp = bp; 454 *bpp = cur->bc_bufs[level];
458 return block; 455 return XFS_BUF_TO_BLOCK(*bpp);
459} 456}
460 457
461/* 458/*
@@ -505,97 +502,6 @@ xfs_btree_get_bufs(
505} 502}
506 503
507/* 504/*
508 * Allocate a new btree cursor.
509 * The cursor is either for allocation (A) or bmap (B) or inodes (I).
510 */
511xfs_btree_cur_t * /* new btree cursor */
512xfs_btree_init_cursor(
513 xfs_mount_t *mp, /* file system mount point */
514 xfs_trans_t *tp, /* transaction pointer */
515 xfs_buf_t *agbp, /* (A only) buffer for agf structure */
516 /* (I only) buffer for agi structure */
517 xfs_agnumber_t agno, /* (AI only) allocation group number */
518 xfs_btnum_t btnum, /* btree identifier */
519 xfs_inode_t *ip, /* (B only) inode owning the btree */
520 int whichfork) /* (B only) data or attr fork */
521{
522 xfs_agf_t *agf; /* (A) allocation group freespace */
523 xfs_agi_t *agi; /* (I) allocation group inodespace */
524 xfs_btree_cur_t *cur; /* return value */
525 xfs_ifork_t *ifp; /* (I) inode fork pointer */
526 int nlevels=0; /* number of levels in the btree */
527
528 ASSERT(xfs_btree_cur_zone != NULL);
529 /*
530 * Allocate a new cursor.
531 */
532 cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_SLEEP);
533 /*
534 * Deduce the number of btree levels from the arguments.
535 */
536 switch (btnum) {
537 case XFS_BTNUM_BNO:
538 case XFS_BTNUM_CNT:
539 agf = XFS_BUF_TO_AGF(agbp);
540 nlevels = be32_to_cpu(agf->agf_levels[btnum]);
541 break;
542 case XFS_BTNUM_BMAP:
543 ifp = XFS_IFORK_PTR(ip, whichfork);
544 nlevels = be16_to_cpu(ifp->if_broot->bb_level) + 1;
545 break;
546 case XFS_BTNUM_INO:
547 agi = XFS_BUF_TO_AGI(agbp);
548 nlevels = be32_to_cpu(agi->agi_level);
549 break;
550 default:
551 ASSERT(0);
552 }
553 /*
554 * Fill in the common fields.
555 */
556 cur->bc_tp = tp;
557 cur->bc_mp = mp;
558 cur->bc_nlevels = nlevels;
559 cur->bc_btnum = btnum;
560 cur->bc_blocklog = mp->m_sb.sb_blocklog;
561 /*
562 * Fill in private fields.
563 */
564 switch (btnum) {
565 case XFS_BTNUM_BNO:
566 case XFS_BTNUM_CNT:
567 /*
568 * Allocation btree fields.
569 */
570 cur->bc_private.a.agbp = agbp;
571 cur->bc_private.a.agno = agno;
572 break;
573 case XFS_BTNUM_INO:
574 /*
575 * Inode allocation btree fields.
576 */
577 cur->bc_private.a.agbp = agbp;
578 cur->bc_private.a.agno = agno;
579 break;
580 case XFS_BTNUM_BMAP:
581 /*
582 * Bmap btree fields.
583 */
584 cur->bc_private.b.forksize = XFS_IFORK_SIZE(ip, whichfork);
585 cur->bc_private.b.ip = ip;
586 cur->bc_private.b.firstblock = NULLFSBLOCK;
587 cur->bc_private.b.flist = NULL;
588 cur->bc_private.b.allocated = 0;
589 cur->bc_private.b.flags = 0;
590 cur->bc_private.b.whichfork = whichfork;
591 break;
592 default:
593 ASSERT(0);
594 }
595 return cur;
596}
597
598/*
599 * Check for the cursor referring to the last block at the given level. 505 * Check for the cursor referring to the last block at the given level.
600 */ 506 */
601int /* 1=is last block, 0=not last block */ 507int /* 1=is last block, 0=not last block */
@@ -603,12 +509,12 @@ xfs_btree_islastblock(
603 xfs_btree_cur_t *cur, /* btree cursor */ 509 xfs_btree_cur_t *cur, /* btree cursor */
604 int level) /* level to check */ 510 int level) /* level to check */
605{ 511{
606 xfs_btree_block_t *block; /* generic btree block pointer */ 512 struct xfs_btree_block *block; /* generic btree block pointer */
607 xfs_buf_t *bp; /* buffer containing block */ 513 xfs_buf_t *bp; /* buffer containing block */
608 514
609 block = xfs_btree_get_block(cur, level, &bp); 515 block = xfs_btree_get_block(cur, level, &bp);
610 xfs_btree_check_block(cur, block, level, bp); 516 xfs_btree_check_block(cur, block, level, bp);
611 if (XFS_BTREE_LONG_PTRS(cur->bc_btnum)) 517 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
612 return be64_to_cpu(block->bb_u.l.bb_rightsib) == NULLDFSBNO; 518 return be64_to_cpu(block->bb_u.l.bb_rightsib) == NULLDFSBNO;
613 else 519 else
614 return be32_to_cpu(block->bb_u.s.bb_rightsib) == NULLAGBLOCK; 520 return be32_to_cpu(block->bb_u.s.bb_rightsib) == NULLAGBLOCK;
@@ -618,12 +524,12 @@ xfs_btree_islastblock(
618 * Change the cursor to point to the first record at the given level. 524 * Change the cursor to point to the first record at the given level.
619 * Other levels are unaffected. 525 * Other levels are unaffected.
620 */ 526 */
621int /* success=1, failure=0 */ 527STATIC int /* success=1, failure=0 */
622xfs_btree_firstrec( 528xfs_btree_firstrec(
623 xfs_btree_cur_t *cur, /* btree cursor */ 529 xfs_btree_cur_t *cur, /* btree cursor */
624 int level) /* level to change */ 530 int level) /* level to change */
625{ 531{
626 xfs_btree_block_t *block; /* generic btree block pointer */ 532 struct xfs_btree_block *block; /* generic btree block pointer */
627 xfs_buf_t *bp; /* buffer containing block */ 533 xfs_buf_t *bp; /* buffer containing block */
628 534
629 /* 535 /*
@@ -634,7 +540,7 @@ xfs_btree_firstrec(
634 /* 540 /*
635 * It's empty, there is no such record. 541 * It's empty, there is no such record.
636 */ 542 */
637 if (!block->bb_h.bb_numrecs) 543 if (!block->bb_numrecs)
638 return 0; 544 return 0;
639 /* 545 /*
640 * Set the ptr value to 1, that's the first record/key. 546 * Set the ptr value to 1, that's the first record/key.
@@ -647,12 +553,12 @@ xfs_btree_firstrec(
647 * Change the cursor to point to the last record in the current block 553 * Change the cursor to point to the last record in the current block
648 * at the given level. Other levels are unaffected. 554 * at the given level. Other levels are unaffected.
649 */ 555 */
650int /* success=1, failure=0 */ 556STATIC int /* success=1, failure=0 */
651xfs_btree_lastrec( 557xfs_btree_lastrec(
652 xfs_btree_cur_t *cur, /* btree cursor */ 558 xfs_btree_cur_t *cur, /* btree cursor */
653 int level) /* level to change */ 559 int level) /* level to change */
654{ 560{
655 xfs_btree_block_t *block; /* generic btree block pointer */ 561 struct xfs_btree_block *block; /* generic btree block pointer */
656 xfs_buf_t *bp; /* buffer containing block */ 562 xfs_buf_t *bp; /* buffer containing block */
657 563
658 /* 564 /*
@@ -663,12 +569,12 @@ xfs_btree_lastrec(
663 /* 569 /*
664 * It's empty, there is no such record. 570 * It's empty, there is no such record.
665 */ 571 */
666 if (!block->bb_h.bb_numrecs) 572 if (!block->bb_numrecs)
667 return 0; 573 return 0;
668 /* 574 /*
669 * Set the ptr value to numrecs, that's the last record/key. 575 * Set the ptr value to numrecs, that's the last record/key.
670 */ 576 */
671 cur->bc_ptrs[level] = be16_to_cpu(block->bb_h.bb_numrecs); 577 cur->bc_ptrs[level] = be16_to_cpu(block->bb_numrecs);
672 return 1; 578 return 1;
673} 579}
674 580
@@ -817,66 +723,84 @@ xfs_btree_reada_bufs(
817 xfs_baread(mp->m_ddev_targp, d, mp->m_bsize * count); 723 xfs_baread(mp->m_ddev_targp, d, mp->m_bsize * count);
818} 724}
819 725
726STATIC int
727xfs_btree_readahead_lblock(
728 struct xfs_btree_cur *cur,
729 int lr,
730 struct xfs_btree_block *block)
731{
732 int rval = 0;
733 xfs_fsblock_t left = be64_to_cpu(block->bb_u.l.bb_leftsib);
734 xfs_fsblock_t right = be64_to_cpu(block->bb_u.l.bb_rightsib);
735
736 if ((lr & XFS_BTCUR_LEFTRA) && left != NULLDFSBNO) {
737 xfs_btree_reada_bufl(cur->bc_mp, left, 1);
738 rval++;
739 }
740
741 if ((lr & XFS_BTCUR_RIGHTRA) && right != NULLDFSBNO) {
742 xfs_btree_reada_bufl(cur->bc_mp, right, 1);
743 rval++;
744 }
745
746 return rval;
747}
748
749STATIC int
750xfs_btree_readahead_sblock(
751 struct xfs_btree_cur *cur,
752 int lr,
753 struct xfs_btree_block *block)
754{
755 int rval = 0;
756 xfs_agblock_t left = be32_to_cpu(block->bb_u.s.bb_leftsib);
757 xfs_agblock_t right = be32_to_cpu(block->bb_u.s.bb_rightsib);
758
759
760 if ((lr & XFS_BTCUR_LEFTRA) && left != NULLAGBLOCK) {
761 xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.a.agno,
762 left, 1);
763 rval++;
764 }
765
766 if ((lr & XFS_BTCUR_RIGHTRA) && right != NULLAGBLOCK) {
767 xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.a.agno,
768 right, 1);
769 rval++;
770 }
771
772 return rval;
773}
774
820/* 775/*
821 * Read-ahead btree blocks, at the given level. 776 * Read-ahead btree blocks, at the given level.
822 * Bits in lr are set from XFS_BTCUR_{LEFT,RIGHT}RA. 777 * Bits in lr are set from XFS_BTCUR_{LEFT,RIGHT}RA.
823 */ 778 */
824int 779STATIC int
825xfs_btree_readahead_core( 780xfs_btree_readahead(
826 xfs_btree_cur_t *cur, /* btree cursor */ 781 struct xfs_btree_cur *cur, /* btree cursor */
827 int lev, /* level in btree */ 782 int lev, /* level in btree */
828 int lr) /* left/right bits */ 783 int lr) /* left/right bits */
829{ 784{
830 xfs_alloc_block_t *a; 785 struct xfs_btree_block *block;
831 xfs_bmbt_block_t *b; 786
832 xfs_inobt_block_t *i; 787 /*
833 int rval = 0; 788 * No readahead needed if we are at the root level and the
789 * btree root is stored in the inode.
790 */
791 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
792 (lev == cur->bc_nlevels - 1))
793 return 0;
794
795 if ((cur->bc_ra[lev] | lr) == cur->bc_ra[lev])
796 return 0;
834 797
835 ASSERT(cur->bc_bufs[lev] != NULL);
836 cur->bc_ra[lev] |= lr; 798 cur->bc_ra[lev] |= lr;
837 switch (cur->bc_btnum) { 799 block = XFS_BUF_TO_BLOCK(cur->bc_bufs[lev]);
838 case XFS_BTNUM_BNO: 800
839 case XFS_BTNUM_CNT: 801 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
840 a = XFS_BUF_TO_ALLOC_BLOCK(cur->bc_bufs[lev]); 802 return xfs_btree_readahead_lblock(cur, lr, block);
841 if ((lr & XFS_BTCUR_LEFTRA) && be32_to_cpu(a->bb_leftsib) != NULLAGBLOCK) { 803 return xfs_btree_readahead_sblock(cur, lr, block);
842 xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.a.agno,
843 be32_to_cpu(a->bb_leftsib), 1);
844 rval++;
845 }
846 if ((lr & XFS_BTCUR_RIGHTRA) && be32_to_cpu(a->bb_rightsib) != NULLAGBLOCK) {
847 xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.a.agno,
848 be32_to_cpu(a->bb_rightsib), 1);
849 rval++;
850 }
851 break;
852 case XFS_BTNUM_BMAP:
853 b = XFS_BUF_TO_BMBT_BLOCK(cur->bc_bufs[lev]);
854 if ((lr & XFS_BTCUR_LEFTRA) && be64_to_cpu(b->bb_leftsib) != NULLDFSBNO) {
855 xfs_btree_reada_bufl(cur->bc_mp, be64_to_cpu(b->bb_leftsib), 1);
856 rval++;
857 }
858 if ((lr & XFS_BTCUR_RIGHTRA) && be64_to_cpu(b->bb_rightsib) != NULLDFSBNO) {
859 xfs_btree_reada_bufl(cur->bc_mp, be64_to_cpu(b->bb_rightsib), 1);
860 rval++;
861 }
862 break;
863 case XFS_BTNUM_INO:
864 i = XFS_BUF_TO_INOBT_BLOCK(cur->bc_bufs[lev]);
865 if ((lr & XFS_BTCUR_LEFTRA) && be32_to_cpu(i->bb_leftsib) != NULLAGBLOCK) {
866 xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.a.agno,
867 be32_to_cpu(i->bb_leftsib), 1);
868 rval++;
869 }
870 if ((lr & XFS_BTCUR_RIGHTRA) && be32_to_cpu(i->bb_rightsib) != NULLAGBLOCK) {
871 xfs_btree_reada_bufs(cur->bc_mp, cur->bc_private.a.agno,
872 be32_to_cpu(i->bb_rightsib), 1);
873 rval++;
874 }
875 break;
876 default:
877 ASSERT(0);
878 }
879 return rval;
880} 804}
881 805
882/* 806/*
@@ -889,7 +813,7 @@ xfs_btree_setbuf(
889 int lev, /* level in btree */ 813 int lev, /* level in btree */
890 xfs_buf_t *bp) /* new buffer to set */ 814 xfs_buf_t *bp) /* new buffer to set */
891{ 815{
892 xfs_btree_block_t *b; /* btree block */ 816 struct xfs_btree_block *b; /* btree block */
893 xfs_buf_t *obp; /* old buffer pointer */ 817 xfs_buf_t *obp; /* old buffer pointer */
894 818
895 obp = cur->bc_bufs[lev]; 819 obp = cur->bc_bufs[lev];
@@ -900,7 +824,7 @@ xfs_btree_setbuf(
900 if (!bp) 824 if (!bp)
901 return; 825 return;
902 b = XFS_BUF_TO_BLOCK(bp); 826 b = XFS_BUF_TO_BLOCK(bp);
903 if (XFS_BTREE_LONG_PTRS(cur->bc_btnum)) { 827 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
904 if (be64_to_cpu(b->bb_u.l.bb_leftsib) == NULLDFSBNO) 828 if (be64_to_cpu(b->bb_u.l.bb_leftsib) == NULLDFSBNO)
905 cur->bc_ra[lev] |= XFS_BTCUR_LEFTRA; 829 cur->bc_ra[lev] |= XFS_BTCUR_LEFTRA;
906 if (be64_to_cpu(b->bb_u.l.bb_rightsib) == NULLDFSBNO) 830 if (be64_to_cpu(b->bb_u.l.bb_rightsib) == NULLDFSBNO)
@@ -912,3 +836,2855 @@ xfs_btree_setbuf(
912 cur->bc_ra[lev] |= XFS_BTCUR_RIGHTRA; 836 cur->bc_ra[lev] |= XFS_BTCUR_RIGHTRA;
913 } 837 }
914} 838}
839
840STATIC int
841xfs_btree_ptr_is_null(
842 struct xfs_btree_cur *cur,
843 union xfs_btree_ptr *ptr)
844{
845 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
846 return be64_to_cpu(ptr->l) == NULLFSBLOCK;
847 else
848 return be32_to_cpu(ptr->s) == NULLAGBLOCK;
849}
850
851STATIC void
852xfs_btree_set_ptr_null(
853 struct xfs_btree_cur *cur,
854 union xfs_btree_ptr *ptr)
855{
856 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
857 ptr->l = cpu_to_be64(NULLFSBLOCK);
858 else
859 ptr->s = cpu_to_be32(NULLAGBLOCK);
860}
861
862/*
863 * Get/set/init sibling pointers
864 */
865STATIC void
866xfs_btree_get_sibling(
867 struct xfs_btree_cur *cur,
868 struct xfs_btree_block *block,
869 union xfs_btree_ptr *ptr,
870 int lr)
871{
872 ASSERT(lr == XFS_BB_LEFTSIB || lr == XFS_BB_RIGHTSIB);
873
874 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
875 if (lr == XFS_BB_RIGHTSIB)
876 ptr->l = block->bb_u.l.bb_rightsib;
877 else
878 ptr->l = block->bb_u.l.bb_leftsib;
879 } else {
880 if (lr == XFS_BB_RIGHTSIB)
881 ptr->s = block->bb_u.s.bb_rightsib;
882 else
883 ptr->s = block->bb_u.s.bb_leftsib;
884 }
885}
886
887STATIC void
888xfs_btree_set_sibling(
889 struct xfs_btree_cur *cur,
890 struct xfs_btree_block *block,
891 union xfs_btree_ptr *ptr,
892 int lr)
893{
894 ASSERT(lr == XFS_BB_LEFTSIB || lr == XFS_BB_RIGHTSIB);
895
896 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
897 if (lr == XFS_BB_RIGHTSIB)
898 block->bb_u.l.bb_rightsib = ptr->l;
899 else
900 block->bb_u.l.bb_leftsib = ptr->l;
901 } else {
902 if (lr == XFS_BB_RIGHTSIB)
903 block->bb_u.s.bb_rightsib = ptr->s;
904 else
905 block->bb_u.s.bb_leftsib = ptr->s;
906 }
907}
908
909STATIC void
910xfs_btree_init_block(
911 struct xfs_btree_cur *cur,
912 int level,
913 int numrecs,
914 struct xfs_btree_block *new) /* new block */
915{
916 new->bb_magic = cpu_to_be32(xfs_magics[cur->bc_btnum]);
917 new->bb_level = cpu_to_be16(level);
918 new->bb_numrecs = cpu_to_be16(numrecs);
919
920 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
921 new->bb_u.l.bb_leftsib = cpu_to_be64(NULLFSBLOCK);
922 new->bb_u.l.bb_rightsib = cpu_to_be64(NULLFSBLOCK);
923 } else {
924 new->bb_u.s.bb_leftsib = cpu_to_be32(NULLAGBLOCK);
925 new->bb_u.s.bb_rightsib = cpu_to_be32(NULLAGBLOCK);
926 }
927}
928
929/*
930 * Return true if ptr is the last record in the btree and
931 * we need to track updateѕ to this record. The decision
932 * will be further refined in the update_lastrec method.
933 */
934STATIC int
935xfs_btree_is_lastrec(
936 struct xfs_btree_cur *cur,
937 struct xfs_btree_block *block,
938 int level)
939{
940 union xfs_btree_ptr ptr;
941
942 if (level > 0)
943 return 0;
944 if (!(cur->bc_flags & XFS_BTREE_LASTREC_UPDATE))
945 return 0;
946
947 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
948 if (!xfs_btree_ptr_is_null(cur, &ptr))
949 return 0;
950 return 1;
951}
952
953STATIC void
954xfs_btree_buf_to_ptr(
955 struct xfs_btree_cur *cur,
956 struct xfs_buf *bp,
957 union xfs_btree_ptr *ptr)
958{
959 if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
960 ptr->l = cpu_to_be64(XFS_DADDR_TO_FSB(cur->bc_mp,
961 XFS_BUF_ADDR(bp)));
962 else {
963 ptr->s = cpu_to_be32(XFS_DADDR_TO_AGBNO(cur->bc_mp,
964 XFS_BUF_ADDR(bp)));
965 }
966}
967
968STATIC xfs_daddr_t
969xfs_btree_ptr_to_daddr(
970 struct xfs_btree_cur *cur,
971 union xfs_btree_ptr *ptr)
972{
973 if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
974 ASSERT(be64_to_cpu(ptr->l) != NULLFSBLOCK);
975
976 return XFS_FSB_TO_DADDR(cur->bc_mp, be64_to_cpu(ptr->l));
977 } else {
978 ASSERT(cur->bc_private.a.agno != NULLAGNUMBER);
979 ASSERT(be32_to_cpu(ptr->s) != NULLAGBLOCK);
980
981 return XFS_AGB_TO_DADDR(cur->bc_mp, cur->bc_private.a.agno,
982 be32_to_cpu(ptr->s));
983 }
984}
985
986STATIC void
987xfs_btree_set_refs(
988 struct xfs_btree_cur *cur,
989 struct xfs_buf *bp)
990{
991 switch (cur->bc_btnum) {
992 case XFS_BTNUM_BNO:
993 case XFS_BTNUM_CNT:
994 XFS_BUF_SET_VTYPE_REF(*bpp, B_FS_MAP, XFS_ALLOC_BTREE_REF);
995 break;
996 case XFS_BTNUM_INO:
997 XFS_BUF_SET_VTYPE_REF(*bpp, B_FS_INOMAP, XFS_INO_BTREE_REF);
998 break;
999 case XFS_BTNUM_BMAP:
1000 XFS_BUF_SET_VTYPE_REF(*bpp, B_FS_MAP, XFS_BMAP_BTREE_REF);
1001 break;
1002 default:
1003 ASSERT(0);
1004 }
1005}
1006
1007STATIC int
1008xfs_btree_get_buf_block(
1009 struct xfs_btree_cur *cur,
1010 union xfs_btree_ptr *ptr,
1011 int flags,
1012 struct xfs_btree_block **block,
1013 struct xfs_buf **bpp)
1014{
1015 struct xfs_mount *mp = cur->bc_mp;
1016 xfs_daddr_t d;
1017
1018 /* need to sort out how callers deal with failures first */
1019 ASSERT(!(flags & XFS_BUF_TRYLOCK));
1020
1021 d = xfs_btree_ptr_to_daddr(cur, ptr);
1022 *bpp = xfs_trans_get_buf(cur->bc_tp, mp->m_ddev_targp, d,
1023 mp->m_bsize, flags);
1024
1025 ASSERT(*bpp);
1026 ASSERT(!XFS_BUF_GETERROR(*bpp));
1027
1028 *block = XFS_BUF_TO_BLOCK(*bpp);
1029 return 0;
1030}
1031
1032/*
1033 * Read in the buffer at the given ptr and return the buffer and
1034 * the block pointer within the buffer.
1035 */
1036STATIC int
1037xfs_btree_read_buf_block(
1038 struct xfs_btree_cur *cur,
1039 union xfs_btree_ptr *ptr,
1040 int level,
1041 int flags,
1042 struct xfs_btree_block **block,
1043 struct xfs_buf **bpp)
1044{
1045 struct xfs_mount *mp = cur->bc_mp;
1046 xfs_daddr_t d;
1047 int error;
1048
1049 /* need to sort out how callers deal with failures first */
1050 ASSERT(!(flags & XFS_BUF_TRYLOCK));
1051
1052 d = xfs_btree_ptr_to_daddr(cur, ptr);
1053 error = xfs_trans_read_buf(mp, cur->bc_tp, mp->m_ddev_targp, d,
1054 mp->m_bsize, flags, bpp);
1055 if (error)
1056 return error;
1057
1058 ASSERT(*bpp != NULL);
1059 ASSERT(!XFS_BUF_GETERROR(*bpp));
1060
1061 xfs_btree_set_refs(cur, *bpp);
1062 *block = XFS_BUF_TO_BLOCK(*bpp);
1063
1064 error = xfs_btree_check_block(cur, *block, level, *bpp);
1065 if (error)
1066 xfs_trans_brelse(cur->bc_tp, *bpp);
1067 return error;
1068}
1069
1070/*
1071 * Copy keys from one btree block to another.
1072 */
1073STATIC void
1074xfs_btree_copy_keys(
1075 struct xfs_btree_cur *cur,
1076 union xfs_btree_key *dst_key,
1077 union xfs_btree_key *src_key,
1078 int numkeys)
1079{
1080 ASSERT(numkeys >= 0);
1081 memcpy(dst_key, src_key, numkeys * cur->bc_ops->key_len);
1082}
1083
1084/*
1085 * Copy records from one btree block to another.
1086 */
1087STATIC void
1088xfs_btree_copy_recs(
1089 struct xfs_btree_cur *cur,
1090 union xfs_btree_rec *dst_rec,
1091 union xfs_btree_rec *src_rec,
1092 int numrecs)
1093{
1094 ASSERT(numrecs >= 0);
1095 memcpy(dst_rec, src_rec, numrecs * cur->bc_ops->rec_len);
1096}
1097
1098/*
1099 * Copy block pointers from one btree block to another.
1100 */
1101STATIC void
1102xfs_btree_copy_ptrs(
1103 struct xfs_btree_cur *cur,
1104 union xfs_btree_ptr *dst_ptr,
1105 union xfs_btree_ptr *src_ptr,
1106 int numptrs)
1107{
1108 ASSERT(numptrs >= 0);
1109 memcpy(dst_ptr, src_ptr, numptrs * xfs_btree_ptr_len(cur));
1110}
1111
1112/*
1113 * Shift keys one index left/right inside a single btree block.
1114 */
1115STATIC void
1116xfs_btree_shift_keys(
1117 struct xfs_btree_cur *cur,
1118 union xfs_btree_key *key,
1119 int dir,
1120 int numkeys)
1121{
1122 char *dst_key;
1123
1124 ASSERT(numkeys >= 0);
1125 ASSERT(dir == 1 || dir == -1);
1126
1127 dst_key = (char *)key + (dir * cur->bc_ops->key_len);
1128 memmove(dst_key, key, numkeys * cur->bc_ops->key_len);
1129}
1130
1131/*
1132 * Shift records one index left/right inside a single btree block.
1133 */
1134STATIC void
1135xfs_btree_shift_recs(
1136 struct xfs_btree_cur *cur,
1137 union xfs_btree_rec *rec,
1138 int dir,
1139 int numrecs)
1140{
1141 char *dst_rec;
1142
1143 ASSERT(numrecs >= 0);
1144 ASSERT(dir == 1 || dir == -1);
1145
1146 dst_rec = (char *)rec + (dir * cur->bc_ops->rec_len);
1147 memmove(dst_rec, rec, numrecs * cur->bc_ops->rec_len);
1148}
1149
1150/*
1151 * Shift block pointers one index left/right inside a single btree block.
1152 */
1153STATIC void
1154xfs_btree_shift_ptrs(
1155 struct xfs_btree_cur *cur,
1156 union xfs_btree_ptr *ptr,
1157 int dir,
1158 int numptrs)
1159{
1160 char *dst_ptr;
1161
1162 ASSERT(numptrs >= 0);
1163 ASSERT(dir == 1 || dir == -1);
1164
1165 dst_ptr = (char *)ptr + (dir * xfs_btree_ptr_len(cur));
1166 memmove(dst_ptr, ptr, numptrs * xfs_btree_ptr_len(cur));
1167}
1168
1169/*
1170 * Log key values from the btree block.
1171 */
1172STATIC void
1173xfs_btree_log_keys(
1174 struct xfs_btree_cur *cur,
1175 struct xfs_buf *bp,
1176 int first,
1177 int last)
1178{
1179 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1180 XFS_BTREE_TRACE_ARGBII(cur, bp, first, last);
1181
1182 if (bp) {
1183 xfs_trans_log_buf(cur->bc_tp, bp,
1184 xfs_btree_key_offset(cur, first),
1185 xfs_btree_key_offset(cur, last + 1) - 1);
1186 } else {
1187 xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip,
1188 xfs_ilog_fbroot(cur->bc_private.b.whichfork));
1189 }
1190
1191 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1192}
1193
1194/*
1195 * Log record values from the btree block.
1196 */
1197void
1198xfs_btree_log_recs(
1199 struct xfs_btree_cur *cur,
1200 struct xfs_buf *bp,
1201 int first,
1202 int last)
1203{
1204 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1205 XFS_BTREE_TRACE_ARGBII(cur, bp, first, last);
1206
1207 xfs_trans_log_buf(cur->bc_tp, bp,
1208 xfs_btree_rec_offset(cur, first),
1209 xfs_btree_rec_offset(cur, last + 1) - 1);
1210
1211 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1212}
1213
1214/*
1215 * Log block pointer fields from a btree block (nonleaf).
1216 */
1217STATIC void
1218xfs_btree_log_ptrs(
1219 struct xfs_btree_cur *cur, /* btree cursor */
1220 struct xfs_buf *bp, /* buffer containing btree block */
1221 int first, /* index of first pointer to log */
1222 int last) /* index of last pointer to log */
1223{
1224 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1225 XFS_BTREE_TRACE_ARGBII(cur, bp, first, last);
1226
1227 if (bp) {
1228 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
1229 int level = xfs_btree_get_level(block);
1230
1231 xfs_trans_log_buf(cur->bc_tp, bp,
1232 xfs_btree_ptr_offset(cur, first, level),
1233 xfs_btree_ptr_offset(cur, last + 1, level) - 1);
1234 } else {
1235 xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip,
1236 xfs_ilog_fbroot(cur->bc_private.b.whichfork));
1237 }
1238
1239 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1240}
1241
1242/*
1243 * Log fields from a btree block header.
1244 */
1245void
1246xfs_btree_log_block(
1247 struct xfs_btree_cur *cur, /* btree cursor */
1248 struct xfs_buf *bp, /* buffer containing btree block */
1249 int fields) /* mask of fields: XFS_BB_... */
1250{
1251 int first; /* first byte offset logged */
1252 int last; /* last byte offset logged */
1253 static const short soffsets[] = { /* table of offsets (short) */
1254 offsetof(struct xfs_btree_block, bb_magic),
1255 offsetof(struct xfs_btree_block, bb_level),
1256 offsetof(struct xfs_btree_block, bb_numrecs),
1257 offsetof(struct xfs_btree_block, bb_u.s.bb_leftsib),
1258 offsetof(struct xfs_btree_block, bb_u.s.bb_rightsib),
1259 XFS_BTREE_SBLOCK_LEN
1260 };
1261 static const short loffsets[] = { /* table of offsets (long) */
1262 offsetof(struct xfs_btree_block, bb_magic),
1263 offsetof(struct xfs_btree_block, bb_level),
1264 offsetof(struct xfs_btree_block, bb_numrecs),
1265 offsetof(struct xfs_btree_block, bb_u.l.bb_leftsib),
1266 offsetof(struct xfs_btree_block, bb_u.l.bb_rightsib),
1267 XFS_BTREE_LBLOCK_LEN
1268 };
1269
1270 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1271 XFS_BTREE_TRACE_ARGBI(cur, bp, fields);
1272
1273 if (bp) {
1274 xfs_btree_offsets(fields,
1275 (cur->bc_flags & XFS_BTREE_LONG_PTRS) ?
1276 loffsets : soffsets,
1277 XFS_BB_NUM_BITS, &first, &last);
1278 xfs_trans_log_buf(cur->bc_tp, bp, first, last);
1279 } else {
1280 xfs_trans_log_inode(cur->bc_tp, cur->bc_private.b.ip,
1281 xfs_ilog_fbroot(cur->bc_private.b.whichfork));
1282 }
1283
1284 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1285}
1286
1287/*
1288 * Increment cursor by one record at the level.
1289 * For nonzero levels the leaf-ward information is untouched.
1290 */
1291int /* error */
1292xfs_btree_increment(
1293 struct xfs_btree_cur *cur,
1294 int level,
1295 int *stat) /* success/failure */
1296{
1297 struct xfs_btree_block *block;
1298 union xfs_btree_ptr ptr;
1299 struct xfs_buf *bp;
1300 int error; /* error return value */
1301 int lev;
1302
1303 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1304 XFS_BTREE_TRACE_ARGI(cur, level);
1305
1306 ASSERT(level < cur->bc_nlevels);
1307
1308 /* Read-ahead to the right at this level. */
1309 xfs_btree_readahead(cur, level, XFS_BTCUR_RIGHTRA);
1310
1311 /* Get a pointer to the btree block. */
1312 block = xfs_btree_get_block(cur, level, &bp);
1313
1314#ifdef DEBUG
1315 error = xfs_btree_check_block(cur, block, level, bp);
1316 if (error)
1317 goto error0;
1318#endif
1319
1320 /* We're done if we remain in the block after the increment. */
1321 if (++cur->bc_ptrs[level] <= xfs_btree_get_numrecs(block))
1322 goto out1;
1323
1324 /* Fail if we just went off the right edge of the tree. */
1325 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
1326 if (xfs_btree_ptr_is_null(cur, &ptr))
1327 goto out0;
1328
1329 XFS_BTREE_STATS_INC(cur, increment);
1330
1331 /*
1332 * March up the tree incrementing pointers.
1333 * Stop when we don't go off the right edge of a block.
1334 */
1335 for (lev = level + 1; lev < cur->bc_nlevels; lev++) {
1336 block = xfs_btree_get_block(cur, lev, &bp);
1337
1338#ifdef DEBUG
1339 error = xfs_btree_check_block(cur, block, lev, bp);
1340 if (error)
1341 goto error0;
1342#endif
1343
1344 if (++cur->bc_ptrs[lev] <= xfs_btree_get_numrecs(block))
1345 break;
1346
1347 /* Read-ahead the right block for the next loop. */
1348 xfs_btree_readahead(cur, lev, XFS_BTCUR_RIGHTRA);
1349 }
1350
1351 /*
1352 * If we went off the root then we are either seriously
1353 * confused or have the tree root in an inode.
1354 */
1355 if (lev == cur->bc_nlevels) {
1356 if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE)
1357 goto out0;
1358 ASSERT(0);
1359 error = EFSCORRUPTED;
1360 goto error0;
1361 }
1362 ASSERT(lev < cur->bc_nlevels);
1363
1364 /*
1365 * Now walk back down the tree, fixing up the cursor's buffer
1366 * pointers and key numbers.
1367 */
1368 for (block = xfs_btree_get_block(cur, lev, &bp); lev > level; ) {
1369 union xfs_btree_ptr *ptrp;
1370
1371 ptrp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[lev], block);
1372 error = xfs_btree_read_buf_block(cur, ptrp, --lev,
1373 0, &block, &bp);
1374 if (error)
1375 goto error0;
1376
1377 xfs_btree_setbuf(cur, lev, bp);
1378 cur->bc_ptrs[lev] = 1;
1379 }
1380out1:
1381 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1382 *stat = 1;
1383 return 0;
1384
1385out0:
1386 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1387 *stat = 0;
1388 return 0;
1389
1390error0:
1391 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
1392 return error;
1393}
1394
1395/*
1396 * Decrement cursor by one record at the level.
1397 * For nonzero levels the leaf-ward information is untouched.
1398 */
1399int /* error */
1400xfs_btree_decrement(
1401 struct xfs_btree_cur *cur,
1402 int level,
1403 int *stat) /* success/failure */
1404{
1405 struct xfs_btree_block *block;
1406 xfs_buf_t *bp;
1407 int error; /* error return value */
1408 int lev;
1409 union xfs_btree_ptr ptr;
1410
1411 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1412 XFS_BTREE_TRACE_ARGI(cur, level);
1413
1414 ASSERT(level < cur->bc_nlevels);
1415
1416 /* Read-ahead to the left at this level. */
1417 xfs_btree_readahead(cur, level, XFS_BTCUR_LEFTRA);
1418
1419 /* We're done if we remain in the block after the decrement. */
1420 if (--cur->bc_ptrs[level] > 0)
1421 goto out1;
1422
1423 /* Get a pointer to the btree block. */
1424 block = xfs_btree_get_block(cur, level, &bp);
1425
1426#ifdef DEBUG
1427 error = xfs_btree_check_block(cur, block, level, bp);
1428 if (error)
1429 goto error0;
1430#endif
1431
1432 /* Fail if we just went off the left edge of the tree. */
1433 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_LEFTSIB);
1434 if (xfs_btree_ptr_is_null(cur, &ptr))
1435 goto out0;
1436
1437 XFS_BTREE_STATS_INC(cur, decrement);
1438
1439 /*
1440 * March up the tree decrementing pointers.
1441 * Stop when we don't go off the left edge of a block.
1442 */
1443 for (lev = level + 1; lev < cur->bc_nlevels; lev++) {
1444 if (--cur->bc_ptrs[lev] > 0)
1445 break;
1446 /* Read-ahead the left block for the next loop. */
1447 xfs_btree_readahead(cur, lev, XFS_BTCUR_LEFTRA);
1448 }
1449
1450 /*
1451 * If we went off the root then we are seriously confused.
1452 * or the root of the tree is in an inode.
1453 */
1454 if (lev == cur->bc_nlevels) {
1455 if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE)
1456 goto out0;
1457 ASSERT(0);
1458 error = EFSCORRUPTED;
1459 goto error0;
1460 }
1461 ASSERT(lev < cur->bc_nlevels);
1462
1463 /*
1464 * Now walk back down the tree, fixing up the cursor's buffer
1465 * pointers and key numbers.
1466 */
1467 for (block = xfs_btree_get_block(cur, lev, &bp); lev > level; ) {
1468 union xfs_btree_ptr *ptrp;
1469
1470 ptrp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[lev], block);
1471 error = xfs_btree_read_buf_block(cur, ptrp, --lev,
1472 0, &block, &bp);
1473 if (error)
1474 goto error0;
1475 xfs_btree_setbuf(cur, lev, bp);
1476 cur->bc_ptrs[lev] = xfs_btree_get_numrecs(block);
1477 }
1478out1:
1479 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1480 *stat = 1;
1481 return 0;
1482
1483out0:
1484 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1485 *stat = 0;
1486 return 0;
1487
1488error0:
1489 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
1490 return error;
1491}
1492
1493STATIC int
1494xfs_btree_lookup_get_block(
1495 struct xfs_btree_cur *cur, /* btree cursor */
1496 int level, /* level in the btree */
1497 union xfs_btree_ptr *pp, /* ptr to btree block */
1498 struct xfs_btree_block **blkp) /* return btree block */
1499{
1500 struct xfs_buf *bp; /* buffer pointer for btree block */
1501 int error = 0;
1502
1503 /* special case the root block if in an inode */
1504 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
1505 (level == cur->bc_nlevels - 1)) {
1506 *blkp = xfs_btree_get_iroot(cur);
1507 return 0;
1508 }
1509
1510 /*
1511 * If the old buffer at this level for the disk address we are
1512 * looking for re-use it.
1513 *
1514 * Otherwise throw it away and get a new one.
1515 */
1516 bp = cur->bc_bufs[level];
1517 if (bp && XFS_BUF_ADDR(bp) == xfs_btree_ptr_to_daddr(cur, pp)) {
1518 *blkp = XFS_BUF_TO_BLOCK(bp);
1519 return 0;
1520 }
1521
1522 error = xfs_btree_read_buf_block(cur, pp, level, 0, blkp, &bp);
1523 if (error)
1524 return error;
1525
1526 xfs_btree_setbuf(cur, level, bp);
1527 return 0;
1528}
1529
1530/*
1531 * Get current search key. For level 0 we don't actually have a key
1532 * structure so we make one up from the record. For all other levels
1533 * we just return the right key.
1534 */
1535STATIC union xfs_btree_key *
1536xfs_lookup_get_search_key(
1537 struct xfs_btree_cur *cur,
1538 int level,
1539 int keyno,
1540 struct xfs_btree_block *block,
1541 union xfs_btree_key *kp)
1542{
1543 if (level == 0) {
1544 cur->bc_ops->init_key_from_rec(kp,
1545 xfs_btree_rec_addr(cur, keyno, block));
1546 return kp;
1547 }
1548
1549 return xfs_btree_key_addr(cur, keyno, block);
1550}
1551
1552/*
1553 * Lookup the record. The cursor is made to point to it, based on dir.
1554 * Return 0 if can't find any such record, 1 for success.
1555 */
1556int /* error */
1557xfs_btree_lookup(
1558 struct xfs_btree_cur *cur, /* btree cursor */
1559 xfs_lookup_t dir, /* <=, ==, or >= */
1560 int *stat) /* success/failure */
1561{
1562 struct xfs_btree_block *block; /* current btree block */
1563 __int64_t diff; /* difference for the current key */
1564 int error; /* error return value */
1565 int keyno; /* current key number */
1566 int level; /* level in the btree */
1567 union xfs_btree_ptr *pp; /* ptr to btree block */
1568 union xfs_btree_ptr ptr; /* ptr to btree block */
1569
1570 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1571 XFS_BTREE_TRACE_ARGI(cur, dir);
1572
1573 XFS_BTREE_STATS_INC(cur, lookup);
1574
1575 block = NULL;
1576 keyno = 0;
1577
1578 /* initialise start pointer from cursor */
1579 cur->bc_ops->init_ptr_from_cur(cur, &ptr);
1580 pp = &ptr;
1581
1582 /*
1583 * Iterate over each level in the btree, starting at the root.
1584 * For each level above the leaves, find the key we need, based
1585 * on the lookup record, then follow the corresponding block
1586 * pointer down to the next level.
1587 */
1588 for (level = cur->bc_nlevels - 1, diff = 1; level >= 0; level--) {
1589 /* Get the block we need to do the lookup on. */
1590 error = xfs_btree_lookup_get_block(cur, level, pp, &block);
1591 if (error)
1592 goto error0;
1593
1594 if (diff == 0) {
1595 /*
1596 * If we already had a key match at a higher level, we
1597 * know we need to use the first entry in this block.
1598 */
1599 keyno = 1;
1600 } else {
1601 /* Otherwise search this block. Do a binary search. */
1602
1603 int high; /* high entry number */
1604 int low; /* low entry number */
1605
1606 /* Set low and high entry numbers, 1-based. */
1607 low = 1;
1608 high = xfs_btree_get_numrecs(block);
1609 if (!high) {
1610 /* Block is empty, must be an empty leaf. */
1611 ASSERT(level == 0 && cur->bc_nlevels == 1);
1612
1613 cur->bc_ptrs[0] = dir != XFS_LOOKUP_LE;
1614 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1615 *stat = 0;
1616 return 0;
1617 }
1618
1619 /* Binary search the block. */
1620 while (low <= high) {
1621 union xfs_btree_key key;
1622 union xfs_btree_key *kp;
1623
1624 XFS_BTREE_STATS_INC(cur, compare);
1625
1626 /* keyno is average of low and high. */
1627 keyno = (low + high) >> 1;
1628
1629 /* Get current search key */
1630 kp = xfs_lookup_get_search_key(cur, level,
1631 keyno, block, &key);
1632
1633 /*
1634 * Compute difference to get next direction:
1635 * - less than, move right
1636 * - greater than, move left
1637 * - equal, we're done
1638 */
1639 diff = cur->bc_ops->key_diff(cur, kp);
1640 if (diff < 0)
1641 low = keyno + 1;
1642 else if (diff > 0)
1643 high = keyno - 1;
1644 else
1645 break;
1646 }
1647 }
1648
1649 /*
1650 * If there are more levels, set up for the next level
1651 * by getting the block number and filling in the cursor.
1652 */
1653 if (level > 0) {
1654 /*
1655 * If we moved left, need the previous key number,
1656 * unless there isn't one.
1657 */
1658 if (diff > 0 && --keyno < 1)
1659 keyno = 1;
1660 pp = xfs_btree_ptr_addr(cur, keyno, block);
1661
1662#ifdef DEBUG
1663 error = xfs_btree_check_ptr(cur, pp, 0, level);
1664 if (error)
1665 goto error0;
1666#endif
1667 cur->bc_ptrs[level] = keyno;
1668 }
1669 }
1670
1671 /* Done with the search. See if we need to adjust the results. */
1672 if (dir != XFS_LOOKUP_LE && diff < 0) {
1673 keyno++;
1674 /*
1675 * If ge search and we went off the end of the block, but it's
1676 * not the last block, we're in the wrong block.
1677 */
1678 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
1679 if (dir == XFS_LOOKUP_GE &&
1680 keyno > xfs_btree_get_numrecs(block) &&
1681 !xfs_btree_ptr_is_null(cur, &ptr)) {
1682 int i;
1683
1684 cur->bc_ptrs[0] = keyno;
1685 error = xfs_btree_increment(cur, 0, &i);
1686 if (error)
1687 goto error0;
1688 XFS_WANT_CORRUPTED_RETURN(i == 1);
1689 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1690 *stat = 1;
1691 return 0;
1692 }
1693 } else if (dir == XFS_LOOKUP_LE && diff > 0)
1694 keyno--;
1695 cur->bc_ptrs[0] = keyno;
1696
1697 /* Return if we succeeded or not. */
1698 if (keyno == 0 || keyno > xfs_btree_get_numrecs(block))
1699 *stat = 0;
1700 else if (dir != XFS_LOOKUP_EQ || diff == 0)
1701 *stat = 1;
1702 else
1703 *stat = 0;
1704 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1705 return 0;
1706
1707error0:
1708 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
1709 return error;
1710}
1711
1712/*
1713 * Update keys at all levels from here to the root along the cursor's path.
1714 */
1715STATIC int
1716xfs_btree_updkey(
1717 struct xfs_btree_cur *cur,
1718 union xfs_btree_key *keyp,
1719 int level)
1720{
1721 struct xfs_btree_block *block;
1722 struct xfs_buf *bp;
1723 union xfs_btree_key *kp;
1724 int ptr;
1725
1726 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1727 XFS_BTREE_TRACE_ARGIK(cur, level, keyp);
1728
1729 ASSERT(!(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) || level >= 1);
1730
1731 /*
1732 * Go up the tree from this level toward the root.
1733 * At each level, update the key value to the value input.
1734 * Stop when we reach a level where the cursor isn't pointing
1735 * at the first entry in the block.
1736 */
1737 for (ptr = 1; ptr == 1 && level < cur->bc_nlevels; level++) {
1738#ifdef DEBUG
1739 int error;
1740#endif
1741 block = xfs_btree_get_block(cur, level, &bp);
1742#ifdef DEBUG
1743 error = xfs_btree_check_block(cur, block, level, bp);
1744 if (error) {
1745 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
1746 return error;
1747 }
1748#endif
1749 ptr = cur->bc_ptrs[level];
1750 kp = xfs_btree_key_addr(cur, ptr, block);
1751 xfs_btree_copy_keys(cur, kp, keyp, 1);
1752 xfs_btree_log_keys(cur, bp, ptr, ptr);
1753 }
1754
1755 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1756 return 0;
1757}
1758
1759/*
1760 * Update the record referred to by cur to the value in the
1761 * given record. This either works (return 0) or gets an
1762 * EFSCORRUPTED error.
1763 */
1764int
1765xfs_btree_update(
1766 struct xfs_btree_cur *cur,
1767 union xfs_btree_rec *rec)
1768{
1769 struct xfs_btree_block *block;
1770 struct xfs_buf *bp;
1771 int error;
1772 int ptr;
1773 union xfs_btree_rec *rp;
1774
1775 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1776 XFS_BTREE_TRACE_ARGR(cur, rec);
1777
1778 /* Pick up the current block. */
1779 block = xfs_btree_get_block(cur, 0, &bp);
1780
1781#ifdef DEBUG
1782 error = xfs_btree_check_block(cur, block, 0, bp);
1783 if (error)
1784 goto error0;
1785#endif
1786 /* Get the address of the rec to be updated. */
1787 ptr = cur->bc_ptrs[0];
1788 rp = xfs_btree_rec_addr(cur, ptr, block);
1789
1790 /* Fill in the new contents and log them. */
1791 xfs_btree_copy_recs(cur, rp, rec, 1);
1792 xfs_btree_log_recs(cur, bp, ptr, ptr);
1793
1794 /*
1795 * If we are tracking the last record in the tree and
1796 * we are at the far right edge of the tree, update it.
1797 */
1798 if (xfs_btree_is_lastrec(cur, block, 0)) {
1799 cur->bc_ops->update_lastrec(cur, block, rec,
1800 ptr, LASTREC_UPDATE);
1801 }
1802
1803 /* Updating first rec in leaf. Pass new key value up to our parent. */
1804 if (ptr == 1) {
1805 union xfs_btree_key key;
1806
1807 cur->bc_ops->init_key_from_rec(&key, rec);
1808 error = xfs_btree_updkey(cur, &key, 1);
1809 if (error)
1810 goto error0;
1811 }
1812
1813 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1814 return 0;
1815
1816error0:
1817 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
1818 return error;
1819}
1820
1821/*
1822 * Move 1 record left from cur/level if possible.
1823 * Update cur to reflect the new path.
1824 */
1825STATIC int /* error */
1826xfs_btree_lshift(
1827 struct xfs_btree_cur *cur,
1828 int level,
1829 int *stat) /* success/failure */
1830{
1831 union xfs_btree_key key; /* btree key */
1832 struct xfs_buf *lbp; /* left buffer pointer */
1833 struct xfs_btree_block *left; /* left btree block */
1834 int lrecs; /* left record count */
1835 struct xfs_buf *rbp; /* right buffer pointer */
1836 struct xfs_btree_block *right; /* right btree block */
1837 int rrecs; /* right record count */
1838 union xfs_btree_ptr lptr; /* left btree pointer */
1839 union xfs_btree_key *rkp = NULL; /* right btree key */
1840 union xfs_btree_ptr *rpp = NULL; /* right address pointer */
1841 union xfs_btree_rec *rrp = NULL; /* right record pointer */
1842 int error; /* error return value */
1843
1844 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
1845 XFS_BTREE_TRACE_ARGI(cur, level);
1846
1847 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
1848 level == cur->bc_nlevels - 1)
1849 goto out0;
1850
1851 /* Set up variables for this block as "right". */
1852 right = xfs_btree_get_block(cur, level, &rbp);
1853
1854#ifdef DEBUG
1855 error = xfs_btree_check_block(cur, right, level, rbp);
1856 if (error)
1857 goto error0;
1858#endif
1859
1860 /* If we've got no left sibling then we can't shift an entry left. */
1861 xfs_btree_get_sibling(cur, right, &lptr, XFS_BB_LEFTSIB);
1862 if (xfs_btree_ptr_is_null(cur, &lptr))
1863 goto out0;
1864
1865 /*
1866 * If the cursor entry is the one that would be moved, don't
1867 * do it... it's too complicated.
1868 */
1869 if (cur->bc_ptrs[level] <= 1)
1870 goto out0;
1871
1872 /* Set up the left neighbor as "left". */
1873 error = xfs_btree_read_buf_block(cur, &lptr, level, 0, &left, &lbp);
1874 if (error)
1875 goto error0;
1876
1877 /* If it's full, it can't take another entry. */
1878 lrecs = xfs_btree_get_numrecs(left);
1879 if (lrecs == cur->bc_ops->get_maxrecs(cur, level))
1880 goto out0;
1881
1882 rrecs = xfs_btree_get_numrecs(right);
1883
1884 /*
1885 * We add one entry to the left side and remove one for the right side.
1886 * Accout for it here, the changes will be updated on disk and logged
1887 * later.
1888 */
1889 lrecs++;
1890 rrecs--;
1891
1892 XFS_BTREE_STATS_INC(cur, lshift);
1893 XFS_BTREE_STATS_ADD(cur, moves, 1);
1894
1895 /*
1896 * If non-leaf, copy a key and a ptr to the left block.
1897 * Log the changes to the left block.
1898 */
1899 if (level > 0) {
1900 /* It's a non-leaf. Move keys and pointers. */
1901 union xfs_btree_key *lkp; /* left btree key */
1902 union xfs_btree_ptr *lpp; /* left address pointer */
1903
1904 lkp = xfs_btree_key_addr(cur, lrecs, left);
1905 rkp = xfs_btree_key_addr(cur, 1, right);
1906
1907 lpp = xfs_btree_ptr_addr(cur, lrecs, left);
1908 rpp = xfs_btree_ptr_addr(cur, 1, right);
1909#ifdef DEBUG
1910 error = xfs_btree_check_ptr(cur, rpp, 0, level);
1911 if (error)
1912 goto error0;
1913#endif
1914 xfs_btree_copy_keys(cur, lkp, rkp, 1);
1915 xfs_btree_copy_ptrs(cur, lpp, rpp, 1);
1916
1917 xfs_btree_log_keys(cur, lbp, lrecs, lrecs);
1918 xfs_btree_log_ptrs(cur, lbp, lrecs, lrecs);
1919
1920 ASSERT(cur->bc_ops->keys_inorder(cur,
1921 xfs_btree_key_addr(cur, lrecs - 1, left), lkp));
1922 } else {
1923 /* It's a leaf. Move records. */
1924 union xfs_btree_rec *lrp; /* left record pointer */
1925
1926 lrp = xfs_btree_rec_addr(cur, lrecs, left);
1927 rrp = xfs_btree_rec_addr(cur, 1, right);
1928
1929 xfs_btree_copy_recs(cur, lrp, rrp, 1);
1930 xfs_btree_log_recs(cur, lbp, lrecs, lrecs);
1931
1932 ASSERT(cur->bc_ops->recs_inorder(cur,
1933 xfs_btree_rec_addr(cur, lrecs - 1, left), lrp));
1934 }
1935
1936 xfs_btree_set_numrecs(left, lrecs);
1937 xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS);
1938
1939 xfs_btree_set_numrecs(right, rrecs);
1940 xfs_btree_log_block(cur, rbp, XFS_BB_NUMRECS);
1941
1942 /*
1943 * Slide the contents of right down one entry.
1944 */
1945 XFS_BTREE_STATS_ADD(cur, moves, rrecs - 1);
1946 if (level > 0) {
1947 /* It's a nonleaf. operate on keys and ptrs */
1948#ifdef DEBUG
1949 int i; /* loop index */
1950
1951 for (i = 0; i < rrecs; i++) {
1952 error = xfs_btree_check_ptr(cur, rpp, i + 1, level);
1953 if (error)
1954 goto error0;
1955 }
1956#endif
1957 xfs_btree_shift_keys(cur,
1958 xfs_btree_key_addr(cur, 2, right),
1959 -1, rrecs);
1960 xfs_btree_shift_ptrs(cur,
1961 xfs_btree_ptr_addr(cur, 2, right),
1962 -1, rrecs);
1963
1964 xfs_btree_log_keys(cur, rbp, 1, rrecs);
1965 xfs_btree_log_ptrs(cur, rbp, 1, rrecs);
1966 } else {
1967 /* It's a leaf. operate on records */
1968 xfs_btree_shift_recs(cur,
1969 xfs_btree_rec_addr(cur, 2, right),
1970 -1, rrecs);
1971 xfs_btree_log_recs(cur, rbp, 1, rrecs);
1972
1973 /*
1974 * If it's the first record in the block, we'll need a key
1975 * structure to pass up to the next level (updkey).
1976 */
1977 cur->bc_ops->init_key_from_rec(&key,
1978 xfs_btree_rec_addr(cur, 1, right));
1979 rkp = &key;
1980 }
1981
1982 /* Update the parent key values of right. */
1983 error = xfs_btree_updkey(cur, rkp, level + 1);
1984 if (error)
1985 goto error0;
1986
1987 /* Slide the cursor value left one. */
1988 cur->bc_ptrs[level]--;
1989
1990 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1991 *stat = 1;
1992 return 0;
1993
1994out0:
1995 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
1996 *stat = 0;
1997 return 0;
1998
1999error0:
2000 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2001 return error;
2002}
2003
2004/*
2005 * Move 1 record right from cur/level if possible.
2006 * Update cur to reflect the new path.
2007 */
2008STATIC int /* error */
2009xfs_btree_rshift(
2010 struct xfs_btree_cur *cur,
2011 int level,
2012 int *stat) /* success/failure */
2013{
2014 union xfs_btree_key key; /* btree key */
2015 struct xfs_buf *lbp; /* left buffer pointer */
2016 struct xfs_btree_block *left; /* left btree block */
2017 struct xfs_buf *rbp; /* right buffer pointer */
2018 struct xfs_btree_block *right; /* right btree block */
2019 struct xfs_btree_cur *tcur; /* temporary btree cursor */
2020 union xfs_btree_ptr rptr; /* right block pointer */
2021 union xfs_btree_key *rkp; /* right btree key */
2022 int rrecs; /* right record count */
2023 int lrecs; /* left record count */
2024 int error; /* error return value */
2025 int i; /* loop counter */
2026
2027 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2028 XFS_BTREE_TRACE_ARGI(cur, level);
2029
2030 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
2031 (level == cur->bc_nlevels - 1))
2032 goto out0;
2033
2034 /* Set up variables for this block as "left". */
2035 left = xfs_btree_get_block(cur, level, &lbp);
2036
2037#ifdef DEBUG
2038 error = xfs_btree_check_block(cur, left, level, lbp);
2039 if (error)
2040 goto error0;
2041#endif
2042
2043 /* If we've got no right sibling then we can't shift an entry right. */
2044 xfs_btree_get_sibling(cur, left, &rptr, XFS_BB_RIGHTSIB);
2045 if (xfs_btree_ptr_is_null(cur, &rptr))
2046 goto out0;
2047
2048 /*
2049 * If the cursor entry is the one that would be moved, don't
2050 * do it... it's too complicated.
2051 */
2052 lrecs = xfs_btree_get_numrecs(left);
2053 if (cur->bc_ptrs[level] >= lrecs)
2054 goto out0;
2055
2056 /* Set up the right neighbor as "right". */
2057 error = xfs_btree_read_buf_block(cur, &rptr, level, 0, &right, &rbp);
2058 if (error)
2059 goto error0;
2060
2061 /* If it's full, it can't take another entry. */
2062 rrecs = xfs_btree_get_numrecs(right);
2063 if (rrecs == cur->bc_ops->get_maxrecs(cur, level))
2064 goto out0;
2065
2066 XFS_BTREE_STATS_INC(cur, rshift);
2067 XFS_BTREE_STATS_ADD(cur, moves, rrecs);
2068
2069 /*
2070 * Make a hole at the start of the right neighbor block, then
2071 * copy the last left block entry to the hole.
2072 */
2073 if (level > 0) {
2074 /* It's a nonleaf. make a hole in the keys and ptrs */
2075 union xfs_btree_key *lkp;
2076 union xfs_btree_ptr *lpp;
2077 union xfs_btree_ptr *rpp;
2078
2079 lkp = xfs_btree_key_addr(cur, lrecs, left);
2080 lpp = xfs_btree_ptr_addr(cur, lrecs, left);
2081 rkp = xfs_btree_key_addr(cur, 1, right);
2082 rpp = xfs_btree_ptr_addr(cur, 1, right);
2083
2084#ifdef DEBUG
2085 for (i = rrecs - 1; i >= 0; i--) {
2086 error = xfs_btree_check_ptr(cur, rpp, i, level);
2087 if (error)
2088 goto error0;
2089 }
2090#endif
2091
2092 xfs_btree_shift_keys(cur, rkp, 1, rrecs);
2093 xfs_btree_shift_ptrs(cur, rpp, 1, rrecs);
2094
2095#ifdef DEBUG
2096 error = xfs_btree_check_ptr(cur, lpp, 0, level);
2097 if (error)
2098 goto error0;
2099#endif
2100
2101 /* Now put the new data in, and log it. */
2102 xfs_btree_copy_keys(cur, rkp, lkp, 1);
2103 xfs_btree_copy_ptrs(cur, rpp, lpp, 1);
2104
2105 xfs_btree_log_keys(cur, rbp, 1, rrecs + 1);
2106 xfs_btree_log_ptrs(cur, rbp, 1, rrecs + 1);
2107
2108 ASSERT(cur->bc_ops->keys_inorder(cur, rkp,
2109 xfs_btree_key_addr(cur, 2, right)));
2110 } else {
2111 /* It's a leaf. make a hole in the records */
2112 union xfs_btree_rec *lrp;
2113 union xfs_btree_rec *rrp;
2114
2115 lrp = xfs_btree_rec_addr(cur, lrecs, left);
2116 rrp = xfs_btree_rec_addr(cur, 1, right);
2117
2118 xfs_btree_shift_recs(cur, rrp, 1, rrecs);
2119
2120 /* Now put the new data in, and log it. */
2121 xfs_btree_copy_recs(cur, rrp, lrp, 1);
2122 xfs_btree_log_recs(cur, rbp, 1, rrecs + 1);
2123
2124 cur->bc_ops->init_key_from_rec(&key, rrp);
2125 rkp = &key;
2126
2127 ASSERT(cur->bc_ops->recs_inorder(cur, rrp,
2128 xfs_btree_rec_addr(cur, 2, right)));
2129 }
2130
2131 /*
2132 * Decrement and log left's numrecs, bump and log right's numrecs.
2133 */
2134 xfs_btree_set_numrecs(left, --lrecs);
2135 xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS);
2136
2137 xfs_btree_set_numrecs(right, ++rrecs);
2138 xfs_btree_log_block(cur, rbp, XFS_BB_NUMRECS);
2139
2140 /*
2141 * Using a temporary cursor, update the parent key values of the
2142 * block on the right.
2143 */
2144 error = xfs_btree_dup_cursor(cur, &tcur);
2145 if (error)
2146 goto error0;
2147 i = xfs_btree_lastrec(tcur, level);
2148 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
2149
2150 error = xfs_btree_increment(tcur, level, &i);
2151 if (error)
2152 goto error1;
2153
2154 error = xfs_btree_updkey(tcur, rkp, level + 1);
2155 if (error)
2156 goto error1;
2157
2158 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
2159
2160 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2161 *stat = 1;
2162 return 0;
2163
2164out0:
2165 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2166 *stat = 0;
2167 return 0;
2168
2169error0:
2170 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2171 return error;
2172
2173error1:
2174 XFS_BTREE_TRACE_CURSOR(tcur, XBT_ERROR);
2175 xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
2176 return error;
2177}
2178
2179/*
2180 * Split cur/level block in half.
2181 * Return new block number and the key to its first
2182 * record (to be inserted into parent).
2183 */
2184STATIC int /* error */
2185xfs_btree_split(
2186 struct xfs_btree_cur *cur,
2187 int level,
2188 union xfs_btree_ptr *ptrp,
2189 union xfs_btree_key *key,
2190 struct xfs_btree_cur **curp,
2191 int *stat) /* success/failure */
2192{
2193 union xfs_btree_ptr lptr; /* left sibling block ptr */
2194 struct xfs_buf *lbp; /* left buffer pointer */
2195 struct xfs_btree_block *left; /* left btree block */
2196 union xfs_btree_ptr rptr; /* right sibling block ptr */
2197 struct xfs_buf *rbp; /* right buffer pointer */
2198 struct xfs_btree_block *right; /* right btree block */
2199 union xfs_btree_ptr rrptr; /* right-right sibling ptr */
2200 struct xfs_buf *rrbp; /* right-right buffer pointer */
2201 struct xfs_btree_block *rrblock; /* right-right btree block */
2202 int lrecs;
2203 int rrecs;
2204 int src_index;
2205 int error; /* error return value */
2206#ifdef DEBUG
2207 int i;
2208#endif
2209
2210 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2211 XFS_BTREE_TRACE_ARGIPK(cur, level, *ptrp, key);
2212
2213 XFS_BTREE_STATS_INC(cur, split);
2214
2215 /* Set up left block (current one). */
2216 left = xfs_btree_get_block(cur, level, &lbp);
2217
2218#ifdef DEBUG
2219 error = xfs_btree_check_block(cur, left, level, lbp);
2220 if (error)
2221 goto error0;
2222#endif
2223
2224 xfs_btree_buf_to_ptr(cur, lbp, &lptr);
2225
2226 /* Allocate the new block. If we can't do it, we're toast. Give up. */
2227 error = cur->bc_ops->alloc_block(cur, &lptr, &rptr, 1, stat);
2228 if (error)
2229 goto error0;
2230 if (*stat == 0)
2231 goto out0;
2232 XFS_BTREE_STATS_INC(cur, alloc);
2233
2234 /* Set up the new block as "right". */
2235 error = xfs_btree_get_buf_block(cur, &rptr, 0, &right, &rbp);
2236 if (error)
2237 goto error0;
2238
2239 /* Fill in the btree header for the new right block. */
2240 xfs_btree_init_block(cur, xfs_btree_get_level(left), 0, right);
2241
2242 /*
2243 * Split the entries between the old and the new block evenly.
2244 * Make sure that if there's an odd number of entries now, that
2245 * each new block will have the same number of entries.
2246 */
2247 lrecs = xfs_btree_get_numrecs(left);
2248 rrecs = lrecs / 2;
2249 if ((lrecs & 1) && cur->bc_ptrs[level] <= rrecs + 1)
2250 rrecs++;
2251 src_index = (lrecs - rrecs + 1);
2252
2253 XFS_BTREE_STATS_ADD(cur, moves, rrecs);
2254
2255 /*
2256 * Copy btree block entries from the left block over to the
2257 * new block, the right. Update the right block and log the
2258 * changes.
2259 */
2260 if (level > 0) {
2261 /* It's a non-leaf. Move keys and pointers. */
2262 union xfs_btree_key *lkp; /* left btree key */
2263 union xfs_btree_ptr *lpp; /* left address pointer */
2264 union xfs_btree_key *rkp; /* right btree key */
2265 union xfs_btree_ptr *rpp; /* right address pointer */
2266
2267 lkp = xfs_btree_key_addr(cur, src_index, left);
2268 lpp = xfs_btree_ptr_addr(cur, src_index, left);
2269 rkp = xfs_btree_key_addr(cur, 1, right);
2270 rpp = xfs_btree_ptr_addr(cur, 1, right);
2271
2272#ifdef DEBUG
2273 for (i = src_index; i < rrecs; i++) {
2274 error = xfs_btree_check_ptr(cur, lpp, i, level);
2275 if (error)
2276 goto error0;
2277 }
2278#endif
2279
2280 xfs_btree_copy_keys(cur, rkp, lkp, rrecs);
2281 xfs_btree_copy_ptrs(cur, rpp, lpp, rrecs);
2282
2283 xfs_btree_log_keys(cur, rbp, 1, rrecs);
2284 xfs_btree_log_ptrs(cur, rbp, 1, rrecs);
2285
2286 /* Grab the keys to the entries moved to the right block */
2287 xfs_btree_copy_keys(cur, key, rkp, 1);
2288 } else {
2289 /* It's a leaf. Move records. */
2290 union xfs_btree_rec *lrp; /* left record pointer */
2291 union xfs_btree_rec *rrp; /* right record pointer */
2292
2293 lrp = xfs_btree_rec_addr(cur, src_index, left);
2294 rrp = xfs_btree_rec_addr(cur, 1, right);
2295
2296 xfs_btree_copy_recs(cur, rrp, lrp, rrecs);
2297 xfs_btree_log_recs(cur, rbp, 1, rrecs);
2298
2299 cur->bc_ops->init_key_from_rec(key,
2300 xfs_btree_rec_addr(cur, 1, right));
2301 }
2302
2303
2304 /*
2305 * Find the left block number by looking in the buffer.
2306 * Adjust numrecs, sibling pointers.
2307 */
2308 xfs_btree_get_sibling(cur, left, &rrptr, XFS_BB_RIGHTSIB);
2309 xfs_btree_set_sibling(cur, right, &rrptr, XFS_BB_RIGHTSIB);
2310 xfs_btree_set_sibling(cur, right, &lptr, XFS_BB_LEFTSIB);
2311 xfs_btree_set_sibling(cur, left, &rptr, XFS_BB_RIGHTSIB);
2312
2313 lrecs -= rrecs;
2314 xfs_btree_set_numrecs(left, lrecs);
2315 xfs_btree_set_numrecs(right, xfs_btree_get_numrecs(right) + rrecs);
2316
2317 xfs_btree_log_block(cur, rbp, XFS_BB_ALL_BITS);
2318 xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS | XFS_BB_RIGHTSIB);
2319
2320 /*
2321 * If there's a block to the new block's right, make that block
2322 * point back to right instead of to left.
2323 */
2324 if (!xfs_btree_ptr_is_null(cur, &rrptr)) {
2325 error = xfs_btree_read_buf_block(cur, &rrptr, level,
2326 0, &rrblock, &rrbp);
2327 if (error)
2328 goto error0;
2329 xfs_btree_set_sibling(cur, rrblock, &rptr, XFS_BB_LEFTSIB);
2330 xfs_btree_log_block(cur, rrbp, XFS_BB_LEFTSIB);
2331 }
2332 /*
2333 * If the cursor is really in the right block, move it there.
2334 * If it's just pointing past the last entry in left, then we'll
2335 * insert there, so don't change anything in that case.
2336 */
2337 if (cur->bc_ptrs[level] > lrecs + 1) {
2338 xfs_btree_setbuf(cur, level, rbp);
2339 cur->bc_ptrs[level] -= lrecs;
2340 }
2341 /*
2342 * If there are more levels, we'll need another cursor which refers
2343 * the right block, no matter where this cursor was.
2344 */
2345 if (level + 1 < cur->bc_nlevels) {
2346 error = xfs_btree_dup_cursor(cur, curp);
2347 if (error)
2348 goto error0;
2349 (*curp)->bc_ptrs[level + 1]++;
2350 }
2351 *ptrp = rptr;
2352 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2353 *stat = 1;
2354 return 0;
2355out0:
2356 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2357 *stat = 0;
2358 return 0;
2359
2360error0:
2361 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2362 return error;
2363}
2364
2365/*
2366 * Copy the old inode root contents into a real block and make the
2367 * broot point to it.
2368 */
2369int /* error */
2370xfs_btree_new_iroot(
2371 struct xfs_btree_cur *cur, /* btree cursor */
2372 int *logflags, /* logging flags for inode */
2373 int *stat) /* return status - 0 fail */
2374{
2375 struct xfs_buf *cbp; /* buffer for cblock */
2376 struct xfs_btree_block *block; /* btree block */
2377 struct xfs_btree_block *cblock; /* child btree block */
2378 union xfs_btree_key *ckp; /* child key pointer */
2379 union xfs_btree_ptr *cpp; /* child ptr pointer */
2380 union xfs_btree_key *kp; /* pointer to btree key */
2381 union xfs_btree_ptr *pp; /* pointer to block addr */
2382 union xfs_btree_ptr nptr; /* new block addr */
2383 int level; /* btree level */
2384 int error; /* error return code */
2385#ifdef DEBUG
2386 int i; /* loop counter */
2387#endif
2388
2389 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2390 XFS_BTREE_STATS_INC(cur, newroot);
2391
2392 ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE);
2393
2394 level = cur->bc_nlevels - 1;
2395
2396 block = xfs_btree_get_iroot(cur);
2397 pp = xfs_btree_ptr_addr(cur, 1, block);
2398
2399 /* Allocate the new block. If we can't do it, we're toast. Give up. */
2400 error = cur->bc_ops->alloc_block(cur, pp, &nptr, 1, stat);
2401 if (error)
2402 goto error0;
2403 if (*stat == 0) {
2404 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2405 return 0;
2406 }
2407 XFS_BTREE_STATS_INC(cur, alloc);
2408
2409 /* Copy the root into a real block. */
2410 error = xfs_btree_get_buf_block(cur, &nptr, 0, &cblock, &cbp);
2411 if (error)
2412 goto error0;
2413
2414 memcpy(cblock, block, xfs_btree_block_len(cur));
2415
2416 be16_add_cpu(&block->bb_level, 1);
2417 xfs_btree_set_numrecs(block, 1);
2418 cur->bc_nlevels++;
2419 cur->bc_ptrs[level + 1] = 1;
2420
2421 kp = xfs_btree_key_addr(cur, 1, block);
2422 ckp = xfs_btree_key_addr(cur, 1, cblock);
2423 xfs_btree_copy_keys(cur, ckp, kp, xfs_btree_get_numrecs(cblock));
2424
2425 cpp = xfs_btree_ptr_addr(cur, 1, cblock);
2426#ifdef DEBUG
2427 for (i = 0; i < be16_to_cpu(cblock->bb_numrecs); i++) {
2428 error = xfs_btree_check_ptr(cur, pp, i, level);
2429 if (error)
2430 goto error0;
2431 }
2432#endif
2433 xfs_btree_copy_ptrs(cur, cpp, pp, xfs_btree_get_numrecs(cblock));
2434
2435#ifdef DEBUG
2436 error = xfs_btree_check_ptr(cur, &nptr, 0, level);
2437 if (error)
2438 goto error0;
2439#endif
2440 xfs_btree_copy_ptrs(cur, pp, &nptr, 1);
2441
2442 xfs_iroot_realloc(cur->bc_private.b.ip,
2443 1 - xfs_btree_get_numrecs(cblock),
2444 cur->bc_private.b.whichfork);
2445
2446 xfs_btree_setbuf(cur, level, cbp);
2447
2448 /*
2449 * Do all this logging at the end so that
2450 * the root is at the right level.
2451 */
2452 xfs_btree_log_block(cur, cbp, XFS_BB_ALL_BITS);
2453 xfs_btree_log_keys(cur, cbp, 1, be16_to_cpu(cblock->bb_numrecs));
2454 xfs_btree_log_ptrs(cur, cbp, 1, be16_to_cpu(cblock->bb_numrecs));
2455
2456 *logflags |=
2457 XFS_ILOG_CORE | XFS_ILOG_FBROOT(cur->bc_private.b.whichfork);
2458 *stat = 1;
2459 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2460 return 0;
2461error0:
2462 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2463 return error;
2464}
2465
2466/*
2467 * Allocate a new root block, fill it in.
2468 */
2469STATIC int /* error */
2470xfs_btree_new_root(
2471 struct xfs_btree_cur *cur, /* btree cursor */
2472 int *stat) /* success/failure */
2473{
2474 struct xfs_btree_block *block; /* one half of the old root block */
2475 struct xfs_buf *bp; /* buffer containing block */
2476 int error; /* error return value */
2477 struct xfs_buf *lbp; /* left buffer pointer */
2478 struct xfs_btree_block *left; /* left btree block */
2479 struct xfs_buf *nbp; /* new (root) buffer */
2480 struct xfs_btree_block *new; /* new (root) btree block */
2481 int nptr; /* new value for key index, 1 or 2 */
2482 struct xfs_buf *rbp; /* right buffer pointer */
2483 struct xfs_btree_block *right; /* right btree block */
2484 union xfs_btree_ptr rptr;
2485 union xfs_btree_ptr lptr;
2486
2487 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2488 XFS_BTREE_STATS_INC(cur, newroot);
2489
2490 /* initialise our start point from the cursor */
2491 cur->bc_ops->init_ptr_from_cur(cur, &rptr);
2492
2493 /* Allocate the new block. If we can't do it, we're toast. Give up. */
2494 error = cur->bc_ops->alloc_block(cur, &rptr, &lptr, 1, stat);
2495 if (error)
2496 goto error0;
2497 if (*stat == 0)
2498 goto out0;
2499 XFS_BTREE_STATS_INC(cur, alloc);
2500
2501 /* Set up the new block. */
2502 error = xfs_btree_get_buf_block(cur, &lptr, 0, &new, &nbp);
2503 if (error)
2504 goto error0;
2505
2506 /* Set the root in the holding structure increasing the level by 1. */
2507 cur->bc_ops->set_root(cur, &lptr, 1);
2508
2509 /*
2510 * At the previous root level there are now two blocks: the old root,
2511 * and the new block generated when it was split. We don't know which
2512 * one the cursor is pointing at, so we set up variables "left" and
2513 * "right" for each case.
2514 */
2515 block = xfs_btree_get_block(cur, cur->bc_nlevels - 1, &bp);
2516
2517#ifdef DEBUG
2518 error = xfs_btree_check_block(cur, block, cur->bc_nlevels - 1, bp);
2519 if (error)
2520 goto error0;
2521#endif
2522
2523 xfs_btree_get_sibling(cur, block, &rptr, XFS_BB_RIGHTSIB);
2524 if (!xfs_btree_ptr_is_null(cur, &rptr)) {
2525 /* Our block is left, pick up the right block. */
2526 lbp = bp;
2527 xfs_btree_buf_to_ptr(cur, lbp, &lptr);
2528 left = block;
2529 error = xfs_btree_read_buf_block(cur, &rptr,
2530 cur->bc_nlevels - 1, 0, &right, &rbp);
2531 if (error)
2532 goto error0;
2533 bp = rbp;
2534 nptr = 1;
2535 } else {
2536 /* Our block is right, pick up the left block. */
2537 rbp = bp;
2538 xfs_btree_buf_to_ptr(cur, rbp, &rptr);
2539 right = block;
2540 xfs_btree_get_sibling(cur, right, &lptr, XFS_BB_LEFTSIB);
2541 error = xfs_btree_read_buf_block(cur, &lptr,
2542 cur->bc_nlevels - 1, 0, &left, &lbp);
2543 if (error)
2544 goto error0;
2545 bp = lbp;
2546 nptr = 2;
2547 }
2548 /* Fill in the new block's btree header and log it. */
2549 xfs_btree_init_block(cur, cur->bc_nlevels, 2, new);
2550 xfs_btree_log_block(cur, nbp, XFS_BB_ALL_BITS);
2551 ASSERT(!xfs_btree_ptr_is_null(cur, &lptr) &&
2552 !xfs_btree_ptr_is_null(cur, &rptr));
2553
2554 /* Fill in the key data in the new root. */
2555 if (xfs_btree_get_level(left) > 0) {
2556 xfs_btree_copy_keys(cur,
2557 xfs_btree_key_addr(cur, 1, new),
2558 xfs_btree_key_addr(cur, 1, left), 1);
2559 xfs_btree_copy_keys(cur,
2560 xfs_btree_key_addr(cur, 2, new),
2561 xfs_btree_key_addr(cur, 1, right), 1);
2562 } else {
2563 cur->bc_ops->init_key_from_rec(
2564 xfs_btree_key_addr(cur, 1, new),
2565 xfs_btree_rec_addr(cur, 1, left));
2566 cur->bc_ops->init_key_from_rec(
2567 xfs_btree_key_addr(cur, 2, new),
2568 xfs_btree_rec_addr(cur, 1, right));
2569 }
2570 xfs_btree_log_keys(cur, nbp, 1, 2);
2571
2572 /* Fill in the pointer data in the new root. */
2573 xfs_btree_copy_ptrs(cur,
2574 xfs_btree_ptr_addr(cur, 1, new), &lptr, 1);
2575 xfs_btree_copy_ptrs(cur,
2576 xfs_btree_ptr_addr(cur, 2, new), &rptr, 1);
2577 xfs_btree_log_ptrs(cur, nbp, 1, 2);
2578
2579 /* Fix up the cursor. */
2580 xfs_btree_setbuf(cur, cur->bc_nlevels, nbp);
2581 cur->bc_ptrs[cur->bc_nlevels] = nptr;
2582 cur->bc_nlevels++;
2583 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2584 *stat = 1;
2585 return 0;
2586error0:
2587 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2588 return error;
2589out0:
2590 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2591 *stat = 0;
2592 return 0;
2593}
2594
2595STATIC int
2596xfs_btree_make_block_unfull(
2597 struct xfs_btree_cur *cur, /* btree cursor */
2598 int level, /* btree level */
2599 int numrecs,/* # of recs in block */
2600 int *oindex,/* old tree index */
2601 int *index, /* new tree index */
2602 union xfs_btree_ptr *nptr, /* new btree ptr */
2603 struct xfs_btree_cur **ncur, /* new btree cursor */
2604 union xfs_btree_rec *nrec, /* new record */
2605 int *stat)
2606{
2607 union xfs_btree_key key; /* new btree key value */
2608 int error = 0;
2609
2610 if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
2611 level == cur->bc_nlevels - 1) {
2612 struct xfs_inode *ip = cur->bc_private.b.ip;
2613
2614 if (numrecs < cur->bc_ops->get_dmaxrecs(cur, level)) {
2615 /* A root block that can be made bigger. */
2616
2617 xfs_iroot_realloc(ip, 1, cur->bc_private.b.whichfork);
2618 } else {
2619 /* A root block that needs replacing */
2620 int logflags = 0;
2621
2622 error = xfs_btree_new_iroot(cur, &logflags, stat);
2623 if (error || *stat == 0)
2624 return error;
2625
2626 xfs_trans_log_inode(cur->bc_tp, ip, logflags);
2627 }
2628
2629 return 0;
2630 }
2631
2632 /* First, try shifting an entry to the right neighbor. */
2633 error = xfs_btree_rshift(cur, level, stat);
2634 if (error || *stat)
2635 return error;
2636
2637 /* Next, try shifting an entry to the left neighbor. */
2638 error = xfs_btree_lshift(cur, level, stat);
2639 if (error)
2640 return error;
2641
2642 if (*stat) {
2643 *oindex = *index = cur->bc_ptrs[level];
2644 return 0;
2645 }
2646
2647 /*
2648 * Next, try splitting the current block in half.
2649 *
2650 * If this works we have to re-set our variables because we
2651 * could be in a different block now.
2652 */
2653 error = xfs_btree_split(cur, level, nptr, &key, ncur, stat);
2654 if (error || *stat == 0)
2655 return error;
2656
2657
2658 *index = cur->bc_ptrs[level];
2659 cur->bc_ops->init_rec_from_key(&key, nrec);
2660 return 0;
2661}
2662
2663/*
2664 * Insert one record/level. Return information to the caller
2665 * allowing the next level up to proceed if necessary.
2666 */
2667STATIC int
2668xfs_btree_insrec(
2669 struct xfs_btree_cur *cur, /* btree cursor */
2670 int level, /* level to insert record at */
2671 union xfs_btree_ptr *ptrp, /* i/o: block number inserted */
2672 union xfs_btree_rec *recp, /* i/o: record data inserted */
2673 struct xfs_btree_cur **curp, /* output: new cursor replacing cur */
2674 int *stat) /* success/failure */
2675{
2676 struct xfs_btree_block *block; /* btree block */
2677 struct xfs_buf *bp; /* buffer for block */
2678 union xfs_btree_key key; /* btree key */
2679 union xfs_btree_ptr nptr; /* new block ptr */
2680 struct xfs_btree_cur *ncur; /* new btree cursor */
2681 union xfs_btree_rec nrec; /* new record count */
2682 int optr; /* old key/record index */
2683 int ptr; /* key/record index */
2684 int numrecs;/* number of records */
2685 int error; /* error return value */
2686#ifdef DEBUG
2687 int i;
2688#endif
2689
2690 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2691 XFS_BTREE_TRACE_ARGIPR(cur, level, *ptrp, recp);
2692
2693 ncur = NULL;
2694
2695 /*
2696 * If we have an external root pointer, and we've made it to the
2697 * root level, allocate a new root block and we're done.
2698 */
2699 if (!(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
2700 (level >= cur->bc_nlevels)) {
2701 error = xfs_btree_new_root(cur, stat);
2702 xfs_btree_set_ptr_null(cur, ptrp);
2703
2704 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2705 return error;
2706 }
2707
2708 /* If we're off the left edge, return failure. */
2709 ptr = cur->bc_ptrs[level];
2710 if (ptr == 0) {
2711 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2712 *stat = 0;
2713 return 0;
2714 }
2715
2716 /* Make a key out of the record data to be inserted, and save it. */
2717 cur->bc_ops->init_key_from_rec(&key, recp);
2718
2719 optr = ptr;
2720
2721 XFS_BTREE_STATS_INC(cur, insrec);
2722
2723 /* Get pointers to the btree buffer and block. */
2724 block = xfs_btree_get_block(cur, level, &bp);
2725 numrecs = xfs_btree_get_numrecs(block);
2726
2727#ifdef DEBUG
2728 error = xfs_btree_check_block(cur, block, level, bp);
2729 if (error)
2730 goto error0;
2731
2732 /* Check that the new entry is being inserted in the right place. */
2733 if (ptr <= numrecs) {
2734 if (level == 0) {
2735 ASSERT(cur->bc_ops->recs_inorder(cur, recp,
2736 xfs_btree_rec_addr(cur, ptr, block)));
2737 } else {
2738 ASSERT(cur->bc_ops->keys_inorder(cur, &key,
2739 xfs_btree_key_addr(cur, ptr, block)));
2740 }
2741 }
2742#endif
2743
2744 /*
2745 * If the block is full, we can't insert the new entry until we
2746 * make the block un-full.
2747 */
2748 xfs_btree_set_ptr_null(cur, &nptr);
2749 if (numrecs == cur->bc_ops->get_maxrecs(cur, level)) {
2750 error = xfs_btree_make_block_unfull(cur, level, numrecs,
2751 &optr, &ptr, &nptr, &ncur, &nrec, stat);
2752 if (error || *stat == 0)
2753 goto error0;
2754 }
2755
2756 /*
2757 * The current block may have changed if the block was
2758 * previously full and we have just made space in it.
2759 */
2760 block = xfs_btree_get_block(cur, level, &bp);
2761 numrecs = xfs_btree_get_numrecs(block);
2762
2763#ifdef DEBUG
2764 error = xfs_btree_check_block(cur, block, level, bp);
2765 if (error)
2766 return error;
2767#endif
2768
2769 /*
2770 * At this point we know there's room for our new entry in the block
2771 * we're pointing at.
2772 */
2773 XFS_BTREE_STATS_ADD(cur, moves, numrecs - ptr + 1);
2774
2775 if (level > 0) {
2776 /* It's a nonleaf. make a hole in the keys and ptrs */
2777 union xfs_btree_key *kp;
2778 union xfs_btree_ptr *pp;
2779
2780 kp = xfs_btree_key_addr(cur, ptr, block);
2781 pp = xfs_btree_ptr_addr(cur, ptr, block);
2782
2783#ifdef DEBUG
2784 for (i = numrecs - ptr; i >= 0; i--) {
2785 error = xfs_btree_check_ptr(cur, pp, i, level);
2786 if (error)
2787 return error;
2788 }
2789#endif
2790
2791 xfs_btree_shift_keys(cur, kp, 1, numrecs - ptr + 1);
2792 xfs_btree_shift_ptrs(cur, pp, 1, numrecs - ptr + 1);
2793
2794#ifdef DEBUG
2795 error = xfs_btree_check_ptr(cur, ptrp, 0, level);
2796 if (error)
2797 goto error0;
2798#endif
2799
2800 /* Now put the new data in, bump numrecs and log it. */
2801 xfs_btree_copy_keys(cur, kp, &key, 1);
2802 xfs_btree_copy_ptrs(cur, pp, ptrp, 1);
2803 numrecs++;
2804 xfs_btree_set_numrecs(block, numrecs);
2805 xfs_btree_log_ptrs(cur, bp, ptr, numrecs);
2806 xfs_btree_log_keys(cur, bp, ptr, numrecs);
2807#ifdef DEBUG
2808 if (ptr < numrecs) {
2809 ASSERT(cur->bc_ops->keys_inorder(cur, kp,
2810 xfs_btree_key_addr(cur, ptr + 1, block)));
2811 }
2812#endif
2813 } else {
2814 /* It's a leaf. make a hole in the records */
2815 union xfs_btree_rec *rp;
2816
2817 rp = xfs_btree_rec_addr(cur, ptr, block);
2818
2819 xfs_btree_shift_recs(cur, rp, 1, numrecs - ptr + 1);
2820
2821 /* Now put the new data in, bump numrecs and log it. */
2822 xfs_btree_copy_recs(cur, rp, recp, 1);
2823 xfs_btree_set_numrecs(block, ++numrecs);
2824 xfs_btree_log_recs(cur, bp, ptr, numrecs);
2825#ifdef DEBUG
2826 if (ptr < numrecs) {
2827 ASSERT(cur->bc_ops->recs_inorder(cur, rp,
2828 xfs_btree_rec_addr(cur, ptr + 1, block)));
2829 }
2830#endif
2831 }
2832
2833 /* Log the new number of records in the btree header. */
2834 xfs_btree_log_block(cur, bp, XFS_BB_NUMRECS);
2835
2836 /* If we inserted at the start of a block, update the parents' keys. */
2837 if (optr == 1) {
2838 error = xfs_btree_updkey(cur, &key, level + 1);
2839 if (error)
2840 goto error0;
2841 }
2842
2843 /*
2844 * If we are tracking the last record in the tree and
2845 * we are at the far right edge of the tree, update it.
2846 */
2847 if (xfs_btree_is_lastrec(cur, block, level)) {
2848 cur->bc_ops->update_lastrec(cur, block, recp,
2849 ptr, LASTREC_INSREC);
2850 }
2851
2852 /*
2853 * Return the new block number, if any.
2854 * If there is one, give back a record value and a cursor too.
2855 */
2856 *ptrp = nptr;
2857 if (!xfs_btree_ptr_is_null(cur, &nptr)) {
2858 *recp = nrec;
2859 *curp = ncur;
2860 }
2861
2862 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2863 *stat = 1;
2864 return 0;
2865
2866error0:
2867 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2868 return error;
2869}
2870
2871/*
2872 * Insert the record at the point referenced by cur.
2873 *
2874 * A multi-level split of the tree on insert will invalidate the original
2875 * cursor. All callers of this function should assume that the cursor is
2876 * no longer valid and revalidate it.
2877 */
2878int
2879xfs_btree_insert(
2880 struct xfs_btree_cur *cur,
2881 int *stat)
2882{
2883 int error; /* error return value */
2884 int i; /* result value, 0 for failure */
2885 int level; /* current level number in btree */
2886 union xfs_btree_ptr nptr; /* new block number (split result) */
2887 struct xfs_btree_cur *ncur; /* new cursor (split result) */
2888 struct xfs_btree_cur *pcur; /* previous level's cursor */
2889 union xfs_btree_rec rec; /* record to insert */
2890
2891 level = 0;
2892 ncur = NULL;
2893 pcur = cur;
2894
2895 xfs_btree_set_ptr_null(cur, &nptr);
2896 cur->bc_ops->init_rec_from_cur(cur, &rec);
2897
2898 /*
2899 * Loop going up the tree, starting at the leaf level.
2900 * Stop when we don't get a split block, that must mean that
2901 * the insert is finished with this level.
2902 */
2903 do {
2904 /*
2905 * Insert nrec/nptr into this level of the tree.
2906 * Note if we fail, nptr will be null.
2907 */
2908 error = xfs_btree_insrec(pcur, level, &nptr, &rec, &ncur, &i);
2909 if (error) {
2910 if (pcur != cur)
2911 xfs_btree_del_cursor(pcur, XFS_BTREE_ERROR);
2912 goto error0;
2913 }
2914
2915 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
2916 level++;
2917
2918 /*
2919 * See if the cursor we just used is trash.
2920 * Can't trash the caller's cursor, but otherwise we should
2921 * if ncur is a new cursor or we're about to be done.
2922 */
2923 if (pcur != cur &&
2924 (ncur || xfs_btree_ptr_is_null(cur, &nptr))) {
2925 /* Save the state from the cursor before we trash it */
2926 if (cur->bc_ops->update_cursor)
2927 cur->bc_ops->update_cursor(pcur, cur);
2928 cur->bc_nlevels = pcur->bc_nlevels;
2929 xfs_btree_del_cursor(pcur, XFS_BTREE_NOERROR);
2930 }
2931 /* If we got a new cursor, switch to it. */
2932 if (ncur) {
2933 pcur = ncur;
2934 ncur = NULL;
2935 }
2936 } while (!xfs_btree_ptr_is_null(cur, &nptr));
2937
2938 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
2939 *stat = i;
2940 return 0;
2941error0:
2942 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
2943 return error;
2944}
2945
2946/*
2947 * Try to merge a non-leaf block back into the inode root.
2948 *
2949 * Note: the killroot names comes from the fact that we're effectively
2950 * killing the old root block. But because we can't just delete the
2951 * inode we have to copy the single block it was pointing to into the
2952 * inode.
2953 */
2954int
2955xfs_btree_kill_iroot(
2956 struct xfs_btree_cur *cur)
2957{
2958 int whichfork = cur->bc_private.b.whichfork;
2959 struct xfs_inode *ip = cur->bc_private.b.ip;
2960 struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, whichfork);
2961 struct xfs_btree_block *block;
2962 struct xfs_btree_block *cblock;
2963 union xfs_btree_key *kp;
2964 union xfs_btree_key *ckp;
2965 union xfs_btree_ptr *pp;
2966 union xfs_btree_ptr *cpp;
2967 struct xfs_buf *cbp;
2968 int level;
2969 int index;
2970 int numrecs;
2971#ifdef DEBUG
2972 union xfs_btree_ptr ptr;
2973 int i;
2974#endif
2975
2976 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
2977
2978 ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE);
2979 ASSERT(cur->bc_nlevels > 1);
2980
2981 /*
2982 * Don't deal with the root block needs to be a leaf case.
2983 * We're just going to turn the thing back into extents anyway.
2984 */
2985 level = cur->bc_nlevels - 1;
2986 if (level == 1)
2987 goto out0;
2988
2989 /*
2990 * Give up if the root has multiple children.
2991 */
2992 block = xfs_btree_get_iroot(cur);
2993 if (xfs_btree_get_numrecs(block) != 1)
2994 goto out0;
2995
2996 cblock = xfs_btree_get_block(cur, level - 1, &cbp);
2997 numrecs = xfs_btree_get_numrecs(cblock);
2998
2999 /*
3000 * Only do this if the next level will fit.
3001 * Then the data must be copied up to the inode,
3002 * instead of freeing the root you free the next level.
3003 */
3004 if (numrecs > cur->bc_ops->get_dmaxrecs(cur, level))
3005 goto out0;
3006
3007 XFS_BTREE_STATS_INC(cur, killroot);
3008
3009#ifdef DEBUG
3010 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_LEFTSIB);
3011 ASSERT(xfs_btree_ptr_is_null(cur, &ptr));
3012 xfs_btree_get_sibling(cur, block, &ptr, XFS_BB_RIGHTSIB);
3013 ASSERT(xfs_btree_ptr_is_null(cur, &ptr));
3014#endif
3015
3016 index = numrecs - cur->bc_ops->get_maxrecs(cur, level);
3017 if (index) {
3018 xfs_iroot_realloc(cur->bc_private.b.ip, index,
3019 cur->bc_private.b.whichfork);
3020 block = ifp->if_broot;
3021 }
3022
3023 be16_add_cpu(&block->bb_numrecs, index);
3024 ASSERT(block->bb_numrecs == cblock->bb_numrecs);
3025
3026 kp = xfs_btree_key_addr(cur, 1, block);
3027 ckp = xfs_btree_key_addr(cur, 1, cblock);
3028 xfs_btree_copy_keys(cur, kp, ckp, numrecs);
3029
3030 pp = xfs_btree_ptr_addr(cur, 1, block);
3031 cpp = xfs_btree_ptr_addr(cur, 1, cblock);
3032#ifdef DEBUG
3033 for (i = 0; i < numrecs; i++) {
3034 int error;
3035
3036 error = xfs_btree_check_ptr(cur, cpp, i, level - 1);
3037 if (error) {
3038 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3039 return error;
3040 }
3041 }
3042#endif
3043 xfs_btree_copy_ptrs(cur, pp, cpp, numrecs);
3044
3045 cur->bc_ops->free_block(cur, cbp);
3046 XFS_BTREE_STATS_INC(cur, free);
3047
3048 cur->bc_bufs[level - 1] = NULL;
3049 be16_add_cpu(&block->bb_level, -1);
3050 xfs_trans_log_inode(cur->bc_tp, ip,
3051 XFS_ILOG_CORE | XFS_ILOG_FBROOT(cur->bc_private.b.whichfork));
3052 cur->bc_nlevels--;
3053out0:
3054 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3055 return 0;
3056}
3057
3058STATIC int
3059xfs_btree_dec_cursor(
3060 struct xfs_btree_cur *cur,
3061 int level,
3062 int *stat)
3063{
3064 int error;
3065 int i;
3066
3067 if (level > 0) {
3068 error = xfs_btree_decrement(cur, level, &i);
3069 if (error)
3070 return error;
3071 }
3072
3073 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3074 *stat = 1;
3075 return 0;
3076}
3077
3078/*
3079 * Single level of the btree record deletion routine.
3080 * Delete record pointed to by cur/level.
3081 * Remove the record from its block then rebalance the tree.
3082 * Return 0 for error, 1 for done, 2 to go on to the next level.
3083 */
3084STATIC int /* error */
3085xfs_btree_delrec(
3086 struct xfs_btree_cur *cur, /* btree cursor */
3087 int level, /* level removing record from */
3088 int *stat) /* fail/done/go-on */
3089{
3090 struct xfs_btree_block *block; /* btree block */
3091 union xfs_btree_ptr cptr; /* current block ptr */
3092 struct xfs_buf *bp; /* buffer for block */
3093 int error; /* error return value */
3094 int i; /* loop counter */
3095 union xfs_btree_key key; /* storage for keyp */
3096 union xfs_btree_key *keyp = &key; /* passed to the next level */
3097 union xfs_btree_ptr lptr; /* left sibling block ptr */
3098 struct xfs_buf *lbp; /* left buffer pointer */
3099 struct xfs_btree_block *left; /* left btree block */
3100 int lrecs = 0; /* left record count */
3101 int ptr; /* key/record index */
3102 union xfs_btree_ptr rptr; /* right sibling block ptr */
3103 struct xfs_buf *rbp; /* right buffer pointer */
3104 struct xfs_btree_block *right; /* right btree block */
3105 struct xfs_btree_block *rrblock; /* right-right btree block */
3106 struct xfs_buf *rrbp; /* right-right buffer pointer */
3107 int rrecs = 0; /* right record count */
3108 struct xfs_btree_cur *tcur; /* temporary btree cursor */
3109 int numrecs; /* temporary numrec count */
3110
3111 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
3112 XFS_BTREE_TRACE_ARGI(cur, level);
3113
3114 tcur = NULL;
3115
3116 /* Get the index of the entry being deleted, check for nothing there. */
3117 ptr = cur->bc_ptrs[level];
3118 if (ptr == 0) {
3119 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3120 *stat = 0;
3121 return 0;
3122 }
3123
3124 /* Get the buffer & block containing the record or key/ptr. */
3125 block = xfs_btree_get_block(cur, level, &bp);
3126 numrecs = xfs_btree_get_numrecs(block);
3127
3128#ifdef DEBUG
3129 error = xfs_btree_check_block(cur, block, level, bp);
3130 if (error)
3131 goto error0;
3132#endif
3133
3134 /* Fail if we're off the end of the block. */
3135 if (ptr > numrecs) {
3136 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3137 *stat = 0;
3138 return 0;
3139 }
3140
3141 XFS_BTREE_STATS_INC(cur, delrec);
3142 XFS_BTREE_STATS_ADD(cur, moves, numrecs - ptr);
3143
3144 /* Excise the entries being deleted. */
3145 if (level > 0) {
3146 /* It's a nonleaf. operate on keys and ptrs */
3147 union xfs_btree_key *lkp;
3148 union xfs_btree_ptr *lpp;
3149
3150 lkp = xfs_btree_key_addr(cur, ptr + 1, block);
3151 lpp = xfs_btree_ptr_addr(cur, ptr + 1, block);
3152
3153#ifdef DEBUG
3154 for (i = 0; i < numrecs - ptr; i++) {
3155 error = xfs_btree_check_ptr(cur, lpp, i, level);
3156 if (error)
3157 goto error0;
3158 }
3159#endif
3160
3161 if (ptr < numrecs) {
3162 xfs_btree_shift_keys(cur, lkp, -1, numrecs - ptr);
3163 xfs_btree_shift_ptrs(cur, lpp, -1, numrecs - ptr);
3164 xfs_btree_log_keys(cur, bp, ptr, numrecs - 1);
3165 xfs_btree_log_ptrs(cur, bp, ptr, numrecs - 1);
3166 }
3167
3168 /*
3169 * If it's the first record in the block, we'll need to pass a
3170 * key up to the next level (updkey).
3171 */
3172 if (ptr == 1)
3173 keyp = xfs_btree_key_addr(cur, 1, block);
3174 } else {
3175 /* It's a leaf. operate on records */
3176 if (ptr < numrecs) {
3177 xfs_btree_shift_recs(cur,
3178 xfs_btree_rec_addr(cur, ptr + 1, block),
3179 -1, numrecs - ptr);
3180 xfs_btree_log_recs(cur, bp, ptr, numrecs - 1);
3181 }
3182
3183 /*
3184 * If it's the first record in the block, we'll need a key
3185 * structure to pass up to the next level (updkey).
3186 */
3187 if (ptr == 1) {
3188 cur->bc_ops->init_key_from_rec(&key,
3189 xfs_btree_rec_addr(cur, 1, block));
3190 keyp = &key;
3191 }
3192 }
3193
3194 /*
3195 * Decrement and log the number of entries in the block.
3196 */
3197 xfs_btree_set_numrecs(block, --numrecs);
3198 xfs_btree_log_block(cur, bp, XFS_BB_NUMRECS);
3199
3200 /*
3201 * If we are tracking the last record in the tree and
3202 * we are at the far right edge of the tree, update it.
3203 */
3204 if (xfs_btree_is_lastrec(cur, block, level)) {
3205 cur->bc_ops->update_lastrec(cur, block, NULL,
3206 ptr, LASTREC_DELREC);
3207 }
3208
3209 /*
3210 * We're at the root level. First, shrink the root block in-memory.
3211 * Try to get rid of the next level down. If we can't then there's
3212 * nothing left to do.
3213 */
3214 if (level == cur->bc_nlevels - 1) {
3215 if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) {
3216 xfs_iroot_realloc(cur->bc_private.b.ip, -1,
3217 cur->bc_private.b.whichfork);
3218
3219 error = xfs_btree_kill_iroot(cur);
3220 if (error)
3221 goto error0;
3222
3223 error = xfs_btree_dec_cursor(cur, level, stat);
3224 if (error)
3225 goto error0;
3226 *stat = 1;
3227 return 0;
3228 }
3229
3230 /*
3231 * If this is the root level, and there's only one entry left,
3232 * and it's NOT the leaf level, then we can get rid of this
3233 * level.
3234 */
3235 if (numrecs == 1 && level > 0) {
3236 union xfs_btree_ptr *pp;
3237 /*
3238 * pp is still set to the first pointer in the block.
3239 * Make it the new root of the btree.
3240 */
3241 pp = xfs_btree_ptr_addr(cur, 1, block);
3242 error = cur->bc_ops->kill_root(cur, bp, level, pp);
3243 if (error)
3244 goto error0;
3245 } else if (level > 0) {
3246 error = xfs_btree_dec_cursor(cur, level, stat);
3247 if (error)
3248 goto error0;
3249 }
3250 *stat = 1;
3251 return 0;
3252 }
3253
3254 /*
3255 * If we deleted the leftmost entry in the block, update the
3256 * key values above us in the tree.
3257 */
3258 if (ptr == 1) {
3259 error = xfs_btree_updkey(cur, keyp, level + 1);
3260 if (error)
3261 goto error0;
3262 }
3263
3264 /*
3265 * If the number of records remaining in the block is at least
3266 * the minimum, we're done.
3267 */
3268 if (numrecs >= cur->bc_ops->get_minrecs(cur, level)) {
3269 error = xfs_btree_dec_cursor(cur, level, stat);
3270 if (error)
3271 goto error0;
3272 return 0;
3273 }
3274
3275 /*
3276 * Otherwise, we have to move some records around to keep the
3277 * tree balanced. Look at the left and right sibling blocks to
3278 * see if we can re-balance by moving only one record.
3279 */
3280 xfs_btree_get_sibling(cur, block, &rptr, XFS_BB_RIGHTSIB);
3281 xfs_btree_get_sibling(cur, block, &lptr, XFS_BB_LEFTSIB);
3282
3283 if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) {
3284 /*
3285 * One child of root, need to get a chance to copy its contents
3286 * into the root and delete it. Can't go up to next level,
3287 * there's nothing to delete there.
3288 */
3289 if (xfs_btree_ptr_is_null(cur, &rptr) &&
3290 xfs_btree_ptr_is_null(cur, &lptr) &&
3291 level == cur->bc_nlevels - 2) {
3292 error = xfs_btree_kill_iroot(cur);
3293 if (!error)
3294 error = xfs_btree_dec_cursor(cur, level, stat);
3295 if (error)
3296 goto error0;
3297 return 0;
3298 }
3299 }
3300
3301 ASSERT(!xfs_btree_ptr_is_null(cur, &rptr) ||
3302 !xfs_btree_ptr_is_null(cur, &lptr));
3303
3304 /*
3305 * Duplicate the cursor so our btree manipulations here won't
3306 * disrupt the next level up.
3307 */
3308 error = xfs_btree_dup_cursor(cur, &tcur);
3309 if (error)
3310 goto error0;
3311
3312 /*
3313 * If there's a right sibling, see if it's ok to shift an entry
3314 * out of it.
3315 */
3316 if (!xfs_btree_ptr_is_null(cur, &rptr)) {
3317 /*
3318 * Move the temp cursor to the last entry in the next block.
3319 * Actually any entry but the first would suffice.
3320 */
3321 i = xfs_btree_lastrec(tcur, level);
3322 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
3323
3324 error = xfs_btree_increment(tcur, level, &i);
3325 if (error)
3326 goto error0;
3327 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
3328
3329 i = xfs_btree_lastrec(tcur, level);
3330 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
3331
3332 /* Grab a pointer to the block. */
3333 right = xfs_btree_get_block(tcur, level, &rbp);
3334#ifdef DEBUG
3335 error = xfs_btree_check_block(tcur, right, level, rbp);
3336 if (error)
3337 goto error0;
3338#endif
3339 /* Grab the current block number, for future use. */
3340 xfs_btree_get_sibling(tcur, right, &cptr, XFS_BB_LEFTSIB);
3341
3342 /*
3343 * If right block is full enough so that removing one entry
3344 * won't make it too empty, and left-shifting an entry out
3345 * of right to us works, we're done.
3346 */
3347 if (xfs_btree_get_numrecs(right) - 1 >=
3348 cur->bc_ops->get_minrecs(tcur, level)) {
3349 error = xfs_btree_lshift(tcur, level, &i);
3350 if (error)
3351 goto error0;
3352 if (i) {
3353 ASSERT(xfs_btree_get_numrecs(block) >=
3354 cur->bc_ops->get_minrecs(tcur, level));
3355
3356 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
3357 tcur = NULL;
3358
3359 error = xfs_btree_dec_cursor(cur, level, stat);
3360 if (error)
3361 goto error0;
3362 return 0;
3363 }
3364 }
3365
3366 /*
3367 * Otherwise, grab the number of records in right for
3368 * future reference, and fix up the temp cursor to point
3369 * to our block again (last record).
3370 */
3371 rrecs = xfs_btree_get_numrecs(right);
3372 if (!xfs_btree_ptr_is_null(cur, &lptr)) {
3373 i = xfs_btree_firstrec(tcur, level);
3374 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
3375
3376 error = xfs_btree_decrement(tcur, level, &i);
3377 if (error)
3378 goto error0;
3379 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
3380 }
3381 }
3382
3383 /*
3384 * If there's a left sibling, see if it's ok to shift an entry
3385 * out of it.
3386 */
3387 if (!xfs_btree_ptr_is_null(cur, &lptr)) {
3388 /*
3389 * Move the temp cursor to the first entry in the
3390 * previous block.
3391 */
3392 i = xfs_btree_firstrec(tcur, level);
3393 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
3394
3395 error = xfs_btree_decrement(tcur, level, &i);
3396 if (error)
3397 goto error0;
3398 i = xfs_btree_firstrec(tcur, level);
3399 XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
3400
3401 /* Grab a pointer to the block. */
3402 left = xfs_btree_get_block(tcur, level, &lbp);
3403#ifdef DEBUG
3404 error = xfs_btree_check_block(cur, left, level, lbp);
3405 if (error)
3406 goto error0;
3407#endif
3408 /* Grab the current block number, for future use. */
3409 xfs_btree_get_sibling(tcur, left, &cptr, XFS_BB_RIGHTSIB);
3410
3411 /*
3412 * If left block is full enough so that removing one entry
3413 * won't make it too empty, and right-shifting an entry out
3414 * of left to us works, we're done.
3415 */
3416 if (xfs_btree_get_numrecs(left) - 1 >=
3417 cur->bc_ops->get_minrecs(tcur, level)) {
3418 error = xfs_btree_rshift(tcur, level, &i);
3419 if (error)
3420 goto error0;
3421 if (i) {
3422 ASSERT(xfs_btree_get_numrecs(block) >=
3423 cur->bc_ops->get_minrecs(tcur, level));
3424 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
3425 tcur = NULL;
3426 if (level == 0)
3427 cur->bc_ptrs[0]++;
3428 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3429 *stat = 1;
3430 return 0;
3431 }
3432 }
3433
3434 /*
3435 * Otherwise, grab the number of records in right for
3436 * future reference.
3437 */
3438 lrecs = xfs_btree_get_numrecs(left);
3439 }
3440
3441 /* Delete the temp cursor, we're done with it. */
3442 xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
3443 tcur = NULL;
3444
3445 /* If here, we need to do a join to keep the tree balanced. */
3446 ASSERT(!xfs_btree_ptr_is_null(cur, &cptr));
3447
3448 if (!xfs_btree_ptr_is_null(cur, &lptr) &&
3449 lrecs + xfs_btree_get_numrecs(block) <=
3450 cur->bc_ops->get_maxrecs(cur, level)) {
3451 /*
3452 * Set "right" to be the starting block,
3453 * "left" to be the left neighbor.
3454 */
3455 rptr = cptr;
3456 right = block;
3457 rbp = bp;
3458 error = xfs_btree_read_buf_block(cur, &lptr, level,
3459 0, &left, &lbp);
3460 if (error)
3461 goto error0;
3462
3463 /*
3464 * If that won't work, see if we can join with the right neighbor block.
3465 */
3466 } else if (!xfs_btree_ptr_is_null(cur, &rptr) &&
3467 rrecs + xfs_btree_get_numrecs(block) <=
3468 cur->bc_ops->get_maxrecs(cur, level)) {
3469 /*
3470 * Set "left" to be the starting block,
3471 * "right" to be the right neighbor.
3472 */
3473 lptr = cptr;
3474 left = block;
3475 lbp = bp;
3476 error = xfs_btree_read_buf_block(cur, &rptr, level,
3477 0, &right, &rbp);
3478 if (error)
3479 goto error0;
3480
3481 /*
3482 * Otherwise, we can't fix the imbalance.
3483 * Just return. This is probably a logic error, but it's not fatal.
3484 */
3485 } else {
3486 error = xfs_btree_dec_cursor(cur, level, stat);
3487 if (error)
3488 goto error0;
3489 return 0;
3490 }
3491
3492 rrecs = xfs_btree_get_numrecs(right);
3493 lrecs = xfs_btree_get_numrecs(left);
3494
3495 /*
3496 * We're now going to join "left" and "right" by moving all the stuff
3497 * in "right" to "left" and deleting "right".
3498 */
3499 XFS_BTREE_STATS_ADD(cur, moves, rrecs);
3500 if (level > 0) {
3501 /* It's a non-leaf. Move keys and pointers. */
3502 union xfs_btree_key *lkp; /* left btree key */
3503 union xfs_btree_ptr *lpp; /* left address pointer */
3504 union xfs_btree_key *rkp; /* right btree key */
3505 union xfs_btree_ptr *rpp; /* right address pointer */
3506
3507 lkp = xfs_btree_key_addr(cur, lrecs + 1, left);
3508 lpp = xfs_btree_ptr_addr(cur, lrecs + 1, left);
3509 rkp = xfs_btree_key_addr(cur, 1, right);
3510 rpp = xfs_btree_ptr_addr(cur, 1, right);
3511#ifdef DEBUG
3512 for (i = 1; i < rrecs; i++) {
3513 error = xfs_btree_check_ptr(cur, rpp, i, level);
3514 if (error)
3515 goto error0;
3516 }
3517#endif
3518 xfs_btree_copy_keys(cur, lkp, rkp, rrecs);
3519 xfs_btree_copy_ptrs(cur, lpp, rpp, rrecs);
3520
3521 xfs_btree_log_keys(cur, lbp, lrecs + 1, lrecs + rrecs);
3522 xfs_btree_log_ptrs(cur, lbp, lrecs + 1, lrecs + rrecs);
3523 } else {
3524 /* It's a leaf. Move records. */
3525 union xfs_btree_rec *lrp; /* left record pointer */
3526 union xfs_btree_rec *rrp; /* right record pointer */
3527
3528 lrp = xfs_btree_rec_addr(cur, lrecs + 1, left);
3529 rrp = xfs_btree_rec_addr(cur, 1, right);
3530
3531 xfs_btree_copy_recs(cur, lrp, rrp, rrecs);
3532 xfs_btree_log_recs(cur, lbp, lrecs + 1, lrecs + rrecs);
3533 }
3534
3535 XFS_BTREE_STATS_INC(cur, join);
3536
3537 /*
3538 * Fix up the the number of records and right block pointer in the
3539 * surviving block, and log it.
3540 */
3541 xfs_btree_set_numrecs(left, lrecs + rrecs);
3542 xfs_btree_get_sibling(cur, right, &cptr, XFS_BB_RIGHTSIB),
3543 xfs_btree_set_sibling(cur, left, &cptr, XFS_BB_RIGHTSIB);
3544 xfs_btree_log_block(cur, lbp, XFS_BB_NUMRECS | XFS_BB_RIGHTSIB);
3545
3546 /* If there is a right sibling, point it to the remaining block. */
3547 xfs_btree_get_sibling(cur, left, &cptr, XFS_BB_RIGHTSIB);
3548 if (!xfs_btree_ptr_is_null(cur, &cptr)) {
3549 error = xfs_btree_read_buf_block(cur, &cptr, level,
3550 0, &rrblock, &rrbp);
3551 if (error)
3552 goto error0;
3553 xfs_btree_set_sibling(cur, rrblock, &lptr, XFS_BB_LEFTSIB);
3554 xfs_btree_log_block(cur, rrbp, XFS_BB_LEFTSIB);
3555 }
3556
3557 /* Free the deleted block. */
3558 error = cur->bc_ops->free_block(cur, rbp);
3559 if (error)
3560 goto error0;
3561 XFS_BTREE_STATS_INC(cur, free);
3562
3563 /*
3564 * If we joined with the left neighbor, set the buffer in the
3565 * cursor to the left block, and fix up the index.
3566 */
3567 if (bp != lbp) {
3568 cur->bc_bufs[level] = lbp;
3569 cur->bc_ptrs[level] += lrecs;
3570 cur->bc_ra[level] = 0;
3571 }
3572 /*
3573 * If we joined with the right neighbor and there's a level above
3574 * us, increment the cursor at that level.
3575 */
3576 else if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) ||
3577 (level + 1 < cur->bc_nlevels)) {
3578 error = xfs_btree_increment(cur, level + 1, &i);
3579 if (error)
3580 goto error0;
3581 }
3582
3583 /*
3584 * Readjust the ptr at this level if it's not a leaf, since it's
3585 * still pointing at the deletion point, which makes the cursor
3586 * inconsistent. If this makes the ptr 0, the caller fixes it up.
3587 * We can't use decrement because it would change the next level up.
3588 */
3589 if (level > 0)
3590 cur->bc_ptrs[level]--;
3591
3592 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3593 /* Return value means the next level up has something to do. */
3594 *stat = 2;
3595 return 0;
3596
3597error0:
3598 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3599 if (tcur)
3600 xfs_btree_del_cursor(tcur, XFS_BTREE_ERROR);
3601 return error;
3602}
3603
3604/*
3605 * Delete the record pointed to by cur.
3606 * The cursor refers to the place where the record was (could be inserted)
3607 * when the operation returns.
3608 */
3609int /* error */
3610xfs_btree_delete(
3611 struct xfs_btree_cur *cur,
3612 int *stat) /* success/failure */
3613{
3614 int error; /* error return value */
3615 int level;
3616 int i;
3617
3618 XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
3619
3620 /*
3621 * Go up the tree, starting at leaf level.
3622 *
3623 * If 2 is returned then a join was done; go to the next level.
3624 * Otherwise we are done.
3625 */
3626 for (level = 0, i = 2; i == 2; level++) {
3627 error = xfs_btree_delrec(cur, level, &i);
3628 if (error)
3629 goto error0;
3630 }
3631
3632 if (i == 0) {
3633 for (level = 1; level < cur->bc_nlevels; level++) {
3634 if (cur->bc_ptrs[level] == 0) {
3635 error = xfs_btree_decrement(cur, level, &i);
3636 if (error)
3637 goto error0;
3638 break;
3639 }
3640 }
3641 }
3642
3643 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
3644 *stat = i;
3645 return 0;
3646error0:
3647 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
3648 return error;
3649}
3650
3651/*
3652 * Get the data from the pointed-to record.
3653 */
3654int /* error */
3655xfs_btree_get_rec(
3656 struct xfs_btree_cur *cur, /* btree cursor */
3657 union xfs_btree_rec **recp, /* output: btree record */
3658 int *stat) /* output: success/failure */
3659{
3660 struct xfs_btree_block *block; /* btree block */
3661 struct xfs_buf *bp; /* buffer pointer */
3662 int ptr; /* record number */
3663#ifdef DEBUG
3664 int error; /* error return value */
3665#endif
3666
3667 ptr = cur->bc_ptrs[0];
3668 block = xfs_btree_get_block(cur, 0, &bp);
3669
3670#ifdef DEBUG
3671 error = xfs_btree_check_block(cur, block, 0, bp);
3672 if (error)
3673 return error;
3674#endif
3675
3676 /*
3677 * Off the right end or left end, return failure.
3678 */
3679 if (ptr > xfs_btree_get_numrecs(block) || ptr <= 0) {
3680 *stat = 0;
3681 return 0;
3682 }
3683
3684 /*
3685 * Point to the record and extract its data.
3686 */
3687 *recp = xfs_btree_rec_addr(cur, ptr, block);
3688 *stat = 1;
3689 return 0;
3690}
generated by cgit v1.2.2 (git 2.25.0) at 2025-01-06 03:22:17 -0500