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ehea: fix skb_frag_size typo
[linux-btrfs-devel.git] / fs / nilfs2 / btree.c
blobb2e3ff34762070a4b37085c051223809b59e4a6c
1 /*
2 * btree.c - NILFS B-tree.
3 *
4 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 *
20 * Written by Koji Sato <koji@osrg.net>.
21 */
22
23 #include <linux/slab.h>
24 #include <linux/string.h>
25 #include <linux/errno.h>
26 #include <linux/pagevec.h>
27 #include "nilfs.h"
28 #include "page.h"
29 #include "btnode.h"
30 #include "btree.h"
31 #include "alloc.h"
32 #include "dat.h"
33
34 static struct nilfs_btree_path *nilfs_btree_alloc_path(void)
35 {
36 struct nilfs_btree_path *path;
37 int level = NILFS_BTREE_LEVEL_DATA;
38
39 path = kmem_cache_alloc(nilfs_btree_path_cache, GFP_NOFS);
40 if (path == NULL)
41 goto out;
42
43 for (; level < NILFS_BTREE_LEVEL_MAX; level++) {
44 path[level].bp_bh = NULL;
45 path[level].bp_sib_bh = NULL;
46 path[level].bp_index = 0;
47 path[level].bp_oldreq.bpr_ptr = NILFS_BMAP_INVALID_PTR;
48 path[level].bp_newreq.bpr_ptr = NILFS_BMAP_INVALID_PTR;
49 path[level].bp_op = NULL;
50 }
51
52 out:
53 return path;
54 }
55
56 static void nilfs_btree_free_path(struct nilfs_btree_path *path)
57 {
58 int level = NILFS_BTREE_LEVEL_DATA;
59
60 for (; level < NILFS_BTREE_LEVEL_MAX; level++)
61 brelse(path[level].bp_bh);
62
63 kmem_cache_free(nilfs_btree_path_cache, path);
64 }
65
66 /*
67 * B-tree node operations
68 */
69 static int nilfs_btree_get_new_block(const struct nilfs_bmap *btree,
70 __u64 ptr, struct buffer_head **bhp)
71 {
72 struct address_space *btnc = &NILFS_BMAP_I(btree)->i_btnode_cache;
73 struct buffer_head *bh;
74
75 bh = nilfs_btnode_create_block(btnc, ptr);
76 if (!bh)
77 return -ENOMEM;
78
79 set_buffer_nilfs_volatile(bh);
80 *bhp = bh;
81 return 0;
82 }
83
84 static int nilfs_btree_node_get_flags(const struct nilfs_btree_node *node)
85 {
86 return node->bn_flags;
87 }
88
89 static void
90 nilfs_btree_node_set_flags(struct nilfs_btree_node *node, int flags)
91 {
92 node->bn_flags = flags;
93 }
94
95 static int nilfs_btree_node_root(const struct nilfs_btree_node *node)
96 {
97 return nilfs_btree_node_get_flags(node) & NILFS_BTREE_NODE_ROOT;
98 }
99
100 static int nilfs_btree_node_get_level(const struct nilfs_btree_node *node)
101 {
102 return node->bn_level;
103 }
104
105 static void
106 nilfs_btree_node_set_level(struct nilfs_btree_node *node, int level)
107 {
108 node->bn_level = level;
109 }
110
111 static int nilfs_btree_node_get_nchildren(const struct nilfs_btree_node *node)
112 {
113 return le16_to_cpu(node->bn_nchildren);
114 }
115
116 static void
117 nilfs_btree_node_set_nchildren(struct nilfs_btree_node *node, int nchildren)
118 {
119 node->bn_nchildren = cpu_to_le16(nchildren);
120 }
121
122 static int nilfs_btree_node_size(const struct nilfs_bmap *btree)
123 {
124 return 1 << btree->b_inode->i_blkbits;
125 }
126
127 static int nilfs_btree_nchildren_per_block(const struct nilfs_bmap *btree)
128 {
129 return btree->b_nchildren_per_block;
130 }
131
132 static __le64 *
133 nilfs_btree_node_dkeys(const struct nilfs_btree_node *node)
134 {
135 return (__le64 *)((char *)(node + 1) +
136 (nilfs_btree_node_root(node) ?
137 0 : NILFS_BTREE_NODE_EXTRA_PAD_SIZE));
138 }
139
140 static __le64 *
141 nilfs_btree_node_dptrs(const struct nilfs_btree_node *node, int ncmax)
142 {
143 return (__le64 *)(nilfs_btree_node_dkeys(node) + ncmax);
144 }
145
146 static __u64
147 nilfs_btree_node_get_key(const struct nilfs_btree_node *node, int index)
148 {
149 return le64_to_cpu(*(nilfs_btree_node_dkeys(node) + index));
150 }
151
152 static void
153 nilfs_btree_node_set_key(struct nilfs_btree_node *node, int index, __u64 key)
154 {
155 *(nilfs_btree_node_dkeys(node) + index) = cpu_to_le64(key);
156 }
157
158 static __u64
159 nilfs_btree_node_get_ptr(const struct nilfs_btree_node *node, int index,
160 int ncmax)
161 {
162 return le64_to_cpu(*(nilfs_btree_node_dptrs(node, ncmax) + index));
163 }
164
165 static void
166 nilfs_btree_node_set_ptr(struct nilfs_btree_node *node, int index, __u64 ptr,
167 int ncmax)
168 {
169 *(nilfs_btree_node_dptrs(node, ncmax) + index) = cpu_to_le64(ptr);
170 }
171
172 static void nilfs_btree_node_init(struct nilfs_btree_node *node, int flags,
173 int level, int nchildren, int ncmax,
174 const __u64 *keys, const __u64 *ptrs)
175 {
176 __le64 *dkeys;
177 __le64 *dptrs;
178 int i;
179
180 nilfs_btree_node_set_flags(node, flags);
181 nilfs_btree_node_set_level(node, level);
182 nilfs_btree_node_set_nchildren(node, nchildren);
183
184 dkeys = nilfs_btree_node_dkeys(node);
185 dptrs = nilfs_btree_node_dptrs(node, ncmax);
186 for (i = 0; i < nchildren; i++) {
187 dkeys[i] = cpu_to_le64(keys[i]);
188 dptrs[i] = cpu_to_le64(ptrs[i]);
189 }
190 }
191
192 /* Assume the buffer heads corresponding to left and right are locked. */
193 static void nilfs_btree_node_move_left(struct nilfs_btree_node *left,
194 struct nilfs_btree_node *right,
195 int n, int lncmax, int rncmax)
196 {
197 __le64 *ldkeys, *rdkeys;
198 __le64 *ldptrs, *rdptrs;
199 int lnchildren, rnchildren;
200
201 ldkeys = nilfs_btree_node_dkeys(left);
202 ldptrs = nilfs_btree_node_dptrs(left, lncmax);
203 lnchildren = nilfs_btree_node_get_nchildren(left);
204
205 rdkeys = nilfs_btree_node_dkeys(right);
206 rdptrs = nilfs_btree_node_dptrs(right, rncmax);
207 rnchildren = nilfs_btree_node_get_nchildren(right);
208
209 memcpy(ldkeys + lnchildren, rdkeys, n * sizeof(*rdkeys));
210 memcpy(ldptrs + lnchildren, rdptrs, n * sizeof(*rdptrs));
211 memmove(rdkeys, rdkeys + n, (rnchildren - n) * sizeof(*rdkeys));
212 memmove(rdptrs, rdptrs + n, (rnchildren - n) * sizeof(*rdptrs));
213
214 lnchildren += n;
215 rnchildren -= n;
216 nilfs_btree_node_set_nchildren(left, lnchildren);
217 nilfs_btree_node_set_nchildren(right, rnchildren);
218 }
219
220 /* Assume that the buffer heads corresponding to left and right are locked. */
221 static void nilfs_btree_node_move_right(struct nilfs_btree_node *left,
222 struct nilfs_btree_node *right,
223 int n, int lncmax, int rncmax)
224 {
225 __le64 *ldkeys, *rdkeys;
226 __le64 *ldptrs, *rdptrs;
227 int lnchildren, rnchildren;
228
229 ldkeys = nilfs_btree_node_dkeys(left);
230 ldptrs = nilfs_btree_node_dptrs(left, lncmax);
231 lnchildren = nilfs_btree_node_get_nchildren(left);
232
233 rdkeys = nilfs_btree_node_dkeys(right);
234 rdptrs = nilfs_btree_node_dptrs(right, rncmax);
235 rnchildren = nilfs_btree_node_get_nchildren(right);
236
237 memmove(rdkeys + n, rdkeys, rnchildren * sizeof(*rdkeys));
238 memmove(rdptrs + n, rdptrs, rnchildren * sizeof(*rdptrs));
239 memcpy(rdkeys, ldkeys + lnchildren - n, n * sizeof(*rdkeys));
240 memcpy(rdptrs, ldptrs + lnchildren - n, n * sizeof(*rdptrs));
241
242 lnchildren -= n;
243 rnchildren += n;
244 nilfs_btree_node_set_nchildren(left, lnchildren);
245 nilfs_btree_node_set_nchildren(right, rnchildren);
246 }
247
248 /* Assume that the buffer head corresponding to node is locked. */
249 static void nilfs_btree_node_insert(struct nilfs_btree_node *node, int index,
250 __u64 key, __u64 ptr, int ncmax)
251 {
252 __le64 *dkeys;
253 __le64 *dptrs;
254 int nchildren;
255
256 dkeys = nilfs_btree_node_dkeys(node);
257 dptrs = nilfs_btree_node_dptrs(node, ncmax);
258 nchildren = nilfs_btree_node_get_nchildren(node);
259 if (index < nchildren) {
260 memmove(dkeys + index + 1, dkeys + index,
261 (nchildren - index) * sizeof(*dkeys));
262 memmove(dptrs + index + 1, dptrs + index,
263 (nchildren - index) * sizeof(*dptrs));
264 }
265 dkeys[index] = cpu_to_le64(key);
266 dptrs[index] = cpu_to_le64(ptr);
267 nchildren++;
268 nilfs_btree_node_set_nchildren(node, nchildren);
269 }
270
271 /* Assume that the buffer head corresponding to node is locked. */
272 static void nilfs_btree_node_delete(struct nilfs_btree_node *node, int index,
273 __u64 *keyp, __u64 *ptrp, int ncmax)
274 {
275 __u64 key;
276 __u64 ptr;
277 __le64 *dkeys;
278 __le64 *dptrs;
279 int nchildren;
280
281 dkeys = nilfs_btree_node_dkeys(node);
282 dptrs = nilfs_btree_node_dptrs(node, ncmax);
283 key = le64_to_cpu(dkeys[index]);
284 ptr = le64_to_cpu(dptrs[index]);
285 nchildren = nilfs_btree_node_get_nchildren(node);
286 if (keyp != NULL)
287 *keyp = key;
288 if (ptrp != NULL)
289 *ptrp = ptr;
290
291 if (index < nchildren - 1) {
292 memmove(dkeys + index, dkeys + index + 1,
293 (nchildren - index - 1) * sizeof(*dkeys));
294 memmove(dptrs + index, dptrs + index + 1,
295 (nchildren - index - 1) * sizeof(*dptrs));
296 }
297 nchildren--;
298 nilfs_btree_node_set_nchildren(node, nchildren);
299 }
300
301 static int nilfs_btree_node_lookup(const struct nilfs_btree_node *node,
302 __u64 key, int *indexp)
303 {
304 __u64 nkey;
305 int index, low, high, s;
306
307 /* binary search */
308 low = 0;
309 high = nilfs_btree_node_get_nchildren(node) - 1;
310 index = 0;
311 s = 0;
312 while (low <= high) {
313 index = (low + high) / 2;
314 nkey = nilfs_btree_node_get_key(node, index);
315 if (nkey == key) {
316 s = 0;
317 goto out;
318 } else if (nkey < key) {
319 low = index + 1;
320 s = -1;
321 } else {
322 high = index - 1;
323 s = 1;
324 }
325 }
326
327 /* adjust index */
328 if (nilfs_btree_node_get_level(node) > NILFS_BTREE_LEVEL_NODE_MIN) {
329 if (s > 0 && index > 0)
330 index--;
331 } else if (s < 0)
332 index++;
333
334 out:
335 *indexp = index;
336
337 return s == 0;
338 }
339
340 /**
341 * nilfs_btree_node_broken - verify consistency of btree node
342 * @node: btree node block to be examined
343 * @size: node size (in bytes)
344 * @blocknr: block number
345 *
346 * Return Value: If node is broken, 1 is returned. Otherwise, 0 is returned.
347 */
348 static int nilfs_btree_node_broken(const struct nilfs_btree_node *node,
349 size_t size, sector_t blocknr)
350 {
351 int level, flags, nchildren;
352 int ret = 0;
353
354 level = nilfs_btree_node_get_level(node);
355 flags = nilfs_btree_node_get_flags(node);
356 nchildren = nilfs_btree_node_get_nchildren(node);
357
358 if (unlikely(level < NILFS_BTREE_LEVEL_NODE_MIN ||
359 level >= NILFS_BTREE_LEVEL_MAX ||
360 (flags & NILFS_BTREE_NODE_ROOT) ||
361 nchildren < 0 ||
362 nchildren > NILFS_BTREE_NODE_NCHILDREN_MAX(size))) {
363 printk(KERN_CRIT "NILFS: bad btree node (blocknr=%llu): "
364 "level = %d, flags = 0x%x, nchildren = %d\n",
365 (unsigned long long)blocknr, level, flags, nchildren);
366 ret = 1;
367 }
368 return ret;
369 }
370
371 int nilfs_btree_broken_node_block(struct buffer_head *bh)
372 {
373 int ret;
374
375 if (buffer_nilfs_checked(bh))
376 return 0;
377
378 ret = nilfs_btree_node_broken((struct nilfs_btree_node *)bh->b_data,
379 bh->b_size, bh->b_blocknr);
380 if (likely(!ret))
381 set_buffer_nilfs_checked(bh);
382 return ret;
383 }
384
385 static struct nilfs_btree_node *
386 nilfs_btree_get_root(const struct nilfs_bmap *btree)
387 {
388 return (struct nilfs_btree_node *)btree->b_u.u_data;
389 }
390
391 static struct nilfs_btree_node *
392 nilfs_btree_get_nonroot_node(const struct nilfs_btree_path *path, int level)
393 {
394 return (struct nilfs_btree_node *)path[level].bp_bh->b_data;
395 }
396
397 static struct nilfs_btree_node *
398 nilfs_btree_get_sib_node(const struct nilfs_btree_path *path, int level)
399 {
400 return (struct nilfs_btree_node *)path[level].bp_sib_bh->b_data;
401 }
402
403 static int nilfs_btree_height(const struct nilfs_bmap *btree)
404 {
405 return nilfs_btree_node_get_level(nilfs_btree_get_root(btree)) + 1;
406 }
407
408 static struct nilfs_btree_node *
409 nilfs_btree_get_node(const struct nilfs_bmap *btree,
410 const struct nilfs_btree_path *path,
411 int level, int *ncmaxp)
412 {
413 struct nilfs_btree_node *node;
414
415 if (level == nilfs_btree_height(btree) - 1) {
416 node = nilfs_btree_get_root(btree);
417 *ncmaxp = NILFS_BTREE_ROOT_NCHILDREN_MAX;
418 } else {
419 node = nilfs_btree_get_nonroot_node(path, level);
420 *ncmaxp = nilfs_btree_nchildren_per_block(btree);
421 }
422 return node;
423 }
424
425 static int
426 nilfs_btree_bad_node(struct nilfs_btree_node *node, int level)
427 {
428 if (unlikely(nilfs_btree_node_get_level(node) != level)) {
429 dump_stack();
430 printk(KERN_CRIT "NILFS: btree level mismatch: %d != %d\n",
431 nilfs_btree_node_get_level(node), level);
432 return 1;
433 }
434 return 0;
435 }
436
437 struct nilfs_btree_readahead_info {
438 struct nilfs_btree_node *node; /* parent node */
439 int max_ra_blocks; /* max nof blocks to read ahead */
440 int index; /* current index on the parent node */
441 int ncmax; /* nof children in the parent node */
442 };
443
444 static int __nilfs_btree_get_block(const struct nilfs_bmap *btree, __u64 ptr,
445 struct buffer_head **bhp,
446 const struct nilfs_btree_readahead_info *ra)
447 {
448 struct address_space *btnc = &NILFS_BMAP_I(btree)->i_btnode_cache;
449 struct buffer_head *bh, *ra_bh;
450 sector_t submit_ptr = 0;
451 int ret;
452
453 ret = nilfs_btnode_submit_block(btnc, ptr, 0, READ, &bh, &submit_ptr);
454 if (ret) {
455 if (ret != -EEXIST)
456 return ret;
457 goto out_check;
458 }
459
460 if (ra) {
461 int i, n;
462 __u64 ptr2;
463
464 /* read ahead sibling nodes */
465 for (n = ra->max_ra_blocks, i = ra->index + 1;
466 n > 0 && i < ra->ncmax; n--, i++) {
467 ptr2 = nilfs_btree_node_get_ptr(ra->node, i, ra->ncmax);
468
469 ret = nilfs_btnode_submit_block(btnc, ptr2, 0, READA,
470 &ra_bh, &submit_ptr);
471 if (likely(!ret || ret == -EEXIST))
472 brelse(ra_bh);
473 else if (ret != -EBUSY)
474 break;
475 if (!buffer_locked(bh))
476 goto out_no_wait;
477 }
478 }
479
480 wait_on_buffer(bh);
481
482 out_no_wait:
483 if (!buffer_uptodate(bh)) {
484 brelse(bh);
485 return -EIO;
486 }
487
488 out_check:
489 if (nilfs_btree_broken_node_block(bh)) {
490 clear_buffer_uptodate(bh);
491 brelse(bh);
492 return -EINVAL;
493 }
494
495 *bhp = bh;
496 return 0;
497 }
498
499 static int nilfs_btree_get_block(const struct nilfs_bmap *btree, __u64 ptr,
500 struct buffer_head **bhp)
501 {
502 return __nilfs_btree_get_block(btree, ptr, bhp, NULL);
503 }
504
505 static int nilfs_btree_do_lookup(const struct nilfs_bmap *btree,
506 struct nilfs_btree_path *path,
507 __u64 key, __u64 *ptrp, int minlevel,
508 int readahead)
509 {
510 struct nilfs_btree_node *node;
511 struct nilfs_btree_readahead_info p, *ra;
512 __u64 ptr;
513 int level, index, found, ncmax, ret;
514
515 node = nilfs_btree_get_root(btree);
516 level = nilfs_btree_node_get_level(node);
517 if (level < minlevel || nilfs_btree_node_get_nchildren(node) <= 0)
518 return -ENOENT;
519
520 found = nilfs_btree_node_lookup(node, key, &index);
521 ptr = nilfs_btree_node_get_ptr(node, index,
522 NILFS_BTREE_ROOT_NCHILDREN_MAX);
523 path[level].bp_bh = NULL;
524 path[level].bp_index = index;
525
526 ncmax = nilfs_btree_nchildren_per_block(btree);
527
528 while (--level >= minlevel) {
529 ra = NULL;
530 if (level == NILFS_BTREE_LEVEL_NODE_MIN && readahead) {
531 p.node = nilfs_btree_get_node(btree, path, level + 1,
532 &p.ncmax);
533 p.index = index;
534 p.max_ra_blocks = 7;
535 ra = &p;
536 }
537 ret = __nilfs_btree_get_block(btree, ptr, &path[level].bp_bh,
538 ra);
539 if (ret < 0)
540 return ret;
541
542 node = nilfs_btree_get_nonroot_node(path, level);
543 if (nilfs_btree_bad_node(node, level))
544 return -EINVAL;
545 if (!found)
546 found = nilfs_btree_node_lookup(node, key, &index);
547 else
548 index = 0;
549 if (index < ncmax) {
550 ptr = nilfs_btree_node_get_ptr(node, index, ncmax);
551 } else {
552 WARN_ON(found || level != NILFS_BTREE_LEVEL_NODE_MIN);
553 /* insert */
554 ptr = NILFS_BMAP_INVALID_PTR;
555 }
556 path[level].bp_index = index;
557 }
558 if (!found)
559 return -ENOENT;
560
561 if (ptrp != NULL)
562 *ptrp = ptr;
563
564 return 0;
565 }
566
567 static int nilfs_btree_do_lookup_last(const struct nilfs_bmap *btree,
568 struct nilfs_btree_path *path,
569 __u64 *keyp, __u64 *ptrp)
570 {
571 struct nilfs_btree_node *node;
572 __u64 ptr;
573 int index, level, ncmax, ret;
574
575 node = nilfs_btree_get_root(btree);
576 index = nilfs_btree_node_get_nchildren(node) - 1;
577 if (index < 0)
578 return -ENOENT;
579 level = nilfs_btree_node_get_level(node);
580 ptr = nilfs_btree_node_get_ptr(node, index,
581 NILFS_BTREE_ROOT_NCHILDREN_MAX);
582 path[level].bp_bh = NULL;
583 path[level].bp_index = index;
584 ncmax = nilfs_btree_nchildren_per_block(btree);
585
586 for (level--; level > 0; level--) {
587 ret = nilfs_btree_get_block(btree, ptr, &path[level].bp_bh);
588 if (ret < 0)
589 return ret;
590 node = nilfs_btree_get_nonroot_node(path, level);
591 if (nilfs_btree_bad_node(node, level))
592 return -EINVAL;
593 index = nilfs_btree_node_get_nchildren(node) - 1;
594 ptr = nilfs_btree_node_get_ptr(node, index, ncmax);
595 path[level].bp_index = index;
596 }
597
598 if (keyp != NULL)
599 *keyp = nilfs_btree_node_get_key(node, index);
600 if (ptrp != NULL)
601 *ptrp = ptr;
602
603 return 0;
604 }
605
606 static int nilfs_btree_lookup(const struct nilfs_bmap *btree,
607 __u64 key, int level, __u64 *ptrp)
608 {
609 struct nilfs_btree_path *path;
610 int ret;
611
612 path = nilfs_btree_alloc_path();
613 if (path == NULL)
614 return -ENOMEM;
615
616 ret = nilfs_btree_do_lookup(btree, path, key, ptrp, level, 0);
617
618 nilfs_btree_free_path(path);
619
620 return ret;
621 }
622
623 static int nilfs_btree_lookup_contig(const struct nilfs_bmap *btree,
624 __u64 key, __u64 *ptrp, unsigned maxblocks)
625 {
626 struct nilfs_btree_path *path;
627 struct nilfs_btree_node *node;
628 struct inode *dat = NULL;
629 __u64 ptr, ptr2;
630 sector_t blocknr;
631 int level = NILFS_BTREE_LEVEL_NODE_MIN;
632 int ret, cnt, index, maxlevel, ncmax;
633 struct nilfs_btree_readahead_info p;
634
635 path = nilfs_btree_alloc_path();
636 if (path == NULL)
637 return -ENOMEM;
638
639 ret = nilfs_btree_do_lookup(btree, path, key, &ptr, level, 1);
640 if (ret < 0)
641 goto out;
642
643 if (NILFS_BMAP_USE_VBN(btree)) {
644 dat = nilfs_bmap_get_dat(btree);
645 ret = nilfs_dat_translate(dat, ptr, &blocknr);
646 if (ret < 0)
647 goto out;
648 ptr = blocknr;
649 }
650 cnt = 1;
651 if (cnt == maxblocks)
652 goto end;
653
654 maxlevel = nilfs_btree_height(btree) - 1;
655 node = nilfs_btree_get_node(btree, path, level, &ncmax);
656 index = path[level].bp_index + 1;
657 for (;;) {
658 while (index < nilfs_btree_node_get_nchildren(node)) {
659 if (nilfs_btree_node_get_key(node, index) !=
660 key + cnt)
661 goto end;
662 ptr2 = nilfs_btree_node_get_ptr(node, index, ncmax);
663 if (dat) {
664 ret = nilfs_dat_translate(dat, ptr2, &blocknr);
665 if (ret < 0)
666 goto out;
667 ptr2 = blocknr;
668 }
669 if (ptr2 != ptr + cnt || ++cnt == maxblocks)
670 goto end;
671 index++;
672 continue;
673 }
674 if (level == maxlevel)
675 break;
676
677 /* look-up right sibling node */
678 p.node = nilfs_btree_get_node(btree, path, level + 1, &p.ncmax);
679 p.index = path[level + 1].bp_index + 1;
680 p.max_ra_blocks = 7;
681 if (p.index >= nilfs_btree_node_get_nchildren(p.node) ||
682 nilfs_btree_node_get_key(p.node, p.index) != key + cnt)
683 break;
684 ptr2 = nilfs_btree_node_get_ptr(p.node, p.index, p.ncmax);
685 path[level + 1].bp_index = p.index;
686
687 brelse(path[level].bp_bh);
688 path[level].bp_bh = NULL;
689
690 ret = __nilfs_btree_get_block(btree, ptr2, &path[level].bp_bh,
691 &p);
692 if (ret < 0)
693 goto out;
694 node = nilfs_btree_get_nonroot_node(path, level);
695 ncmax = nilfs_btree_nchildren_per_block(btree);
696 index = 0;
697 path[level].bp_index = index;
698 }
699 end:
700 *ptrp = ptr;
701 ret = cnt;
702 out:
703 nilfs_btree_free_path(path);
704 return ret;
705 }
706
707 static void nilfs_btree_promote_key(struct nilfs_bmap *btree,
708 struct nilfs_btree_path *path,
709 int level, __u64 key)
710 {
711 if (level < nilfs_btree_height(btree) - 1) {
712 do {
713 nilfs_btree_node_set_key(
714 nilfs_btree_get_nonroot_node(path, level),
715 path[level].bp_index, key);
716 if (!buffer_dirty(path[level].bp_bh))
717 mark_buffer_dirty(path[level].bp_bh);
718 } while ((path[level].bp_index == 0) &&
719 (++level < nilfs_btree_height(btree) - 1));
720 }
721
722 /* root */
723 if (level == nilfs_btree_height(btree) - 1) {
724 nilfs_btree_node_set_key(nilfs_btree_get_root(btree),
725 path[level].bp_index, key);
726 }
727 }
728
729 static void nilfs_btree_do_insert(struct nilfs_bmap *btree,
730 struct nilfs_btree_path *path,
731 int level, __u64 *keyp, __u64 *ptrp)
732 {
733 struct nilfs_btree_node *node;
734 int ncblk;
735
736 if (level < nilfs_btree_height(btree) - 1) {
737 node = nilfs_btree_get_nonroot_node(path, level);
738 ncblk = nilfs_btree_nchildren_per_block(btree);
739 nilfs_btree_node_insert(node, path[level].bp_index,
740 *keyp, *ptrp, ncblk);
741 if (!buffer_dirty(path[level].bp_bh))
742 mark_buffer_dirty(path[level].bp_bh);
743
744 if (path[level].bp_index == 0)
745 nilfs_btree_promote_key(btree, path, level + 1,
746 nilfs_btree_node_get_key(node,
747 0));
748 } else {
749 node = nilfs_btree_get_root(btree);
750 nilfs_btree_node_insert(node, path[level].bp_index,
751 *keyp, *ptrp,
752 NILFS_BTREE_ROOT_NCHILDREN_MAX);
753 }
754 }
755
756 static void nilfs_btree_carry_left(struct nilfs_bmap *btree,
757 struct nilfs_btree_path *path,
758 int level, __u64 *keyp, __u64 *ptrp)
759 {
760 struct nilfs_btree_node *node, *left;
761 int nchildren, lnchildren, n, move, ncblk;
762
763 node = nilfs_btree_get_nonroot_node(path, level);
764 left = nilfs_btree_get_sib_node(path, level);
765 nchildren = nilfs_btree_node_get_nchildren(node);
766 lnchildren = nilfs_btree_node_get_nchildren(left);
767 ncblk = nilfs_btree_nchildren_per_block(btree);
768 move = 0;
769
770 n = (nchildren + lnchildren + 1) / 2 - lnchildren;
771 if (n > path[level].bp_index) {
772 /* move insert point */
773 n--;
774 move = 1;
775 }
776
777 nilfs_btree_node_move_left(left, node, n, ncblk, ncblk);
778
779 if (!buffer_dirty(path[level].bp_bh))
780 mark_buffer_dirty(path[level].bp_bh);
781 if (!buffer_dirty(path[level].bp_sib_bh))
782 mark_buffer_dirty(path[level].bp_sib_bh);
783
784 nilfs_btree_promote_key(btree, path, level + 1,
785 nilfs_btree_node_get_key(node, 0));
786
787 if (move) {
788 brelse(path[level].bp_bh);
789 path[level].bp_bh = path[level].bp_sib_bh;
790 path[level].bp_sib_bh = NULL;
791 path[level].bp_index += lnchildren;
792 path[level + 1].bp_index--;
793 } else {
794 brelse(path[level].bp_sib_bh);
795 path[level].bp_sib_bh = NULL;
796 path[level].bp_index -= n;
797 }
798
799 nilfs_btree_do_insert(btree, path, level, keyp, ptrp);
800 }
801
802 static void nilfs_btree_carry_right(struct nilfs_bmap *btree,
803 struct nilfs_btree_path *path,
804 int level, __u64 *keyp, __u64 *ptrp)
805 {
806 struct nilfs_btree_node *node, *right;
807 int nchildren, rnchildren, n, move, ncblk;
808
809 node = nilfs_btree_get_nonroot_node(path, level);
810 right = nilfs_btree_get_sib_node(path, level);
811 nchildren = nilfs_btree_node_get_nchildren(node);
812 rnchildren = nilfs_btree_node_get_nchildren(right);
813 ncblk = nilfs_btree_nchildren_per_block(btree);
814 move = 0;
815
816 n = (nchildren + rnchildren + 1) / 2 - rnchildren;
817 if (n > nchildren - path[level].bp_index) {
818 /* move insert point */
819 n--;
820 move = 1;
821 }
822
823 nilfs_btree_node_move_right(node, right, n, ncblk, ncblk);
824
825 if (!buffer_dirty(path[level].bp_bh))
826 mark_buffer_dirty(path[level].bp_bh);
827 if (!buffer_dirty(path[level].bp_sib_bh))
828 mark_buffer_dirty(path[level].bp_sib_bh);
829
830 path[level + 1].bp_index++;
831 nilfs_btree_promote_key(btree, path, level + 1,
832 nilfs_btree_node_get_key(right, 0));
833 path[level + 1].bp_index--;
834
835 if (move) {
836 brelse(path[level].bp_bh);
837 path[level].bp_bh = path[level].bp_sib_bh;
838 path[level].bp_sib_bh = NULL;
839 path[level].bp_index -= nilfs_btree_node_get_nchildren(node);
840 path[level + 1].bp_index++;
841 } else {
842 brelse(path[level].bp_sib_bh);
843 path[level].bp_sib_bh = NULL;
844 }
845
846 nilfs_btree_do_insert(btree, path, level, keyp, ptrp);
847 }
848
849 static void nilfs_btree_split(struct nilfs_bmap *btree,
850 struct nilfs_btree_path *path,
851 int level, __u64 *keyp, __u64 *ptrp)
852 {
853 struct nilfs_btree_node *node, *right;
854 __u64 newkey;
855 __u64 newptr;
856 int nchildren, n, move, ncblk;
857
858 node = nilfs_btree_get_nonroot_node(path, level);
859 right = nilfs_btree_get_sib_node(path, level);
860 nchildren = nilfs_btree_node_get_nchildren(node);
861 ncblk = nilfs_btree_nchildren_per_block(btree);
862 move = 0;
863
864 n = (nchildren + 1) / 2;
865 if (n > nchildren - path[level].bp_index) {
866 n--;
867 move = 1;
868 }
869
870 nilfs_btree_node_move_right(node, right, n, ncblk, ncblk);
871
872 if (!buffer_dirty(path[level].bp_bh))
873 mark_buffer_dirty(path[level].bp_bh);
874 if (!buffer_dirty(path[level].bp_sib_bh))
875 mark_buffer_dirty(path[level].bp_sib_bh);
876
877 newkey = nilfs_btree_node_get_key(right, 0);
878 newptr = path[level].bp_newreq.bpr_ptr;
879
880 if (move) {
881 path[level].bp_index -= nilfs_btree_node_get_nchildren(node);
882 nilfs_btree_node_insert(right, path[level].bp_index,
883 *keyp, *ptrp, ncblk);
884
885 *keyp = nilfs_btree_node_get_key(right, 0);
886 *ptrp = path[level].bp_newreq.bpr_ptr;
887
888 brelse(path[level].bp_bh);
889 path[level].bp_bh = path[level].bp_sib_bh;
890 path[level].bp_sib_bh = NULL;
891 } else {
892 nilfs_btree_do_insert(btree, path, level, keyp, ptrp);
893
894 *keyp = nilfs_btree_node_get_key(right, 0);
895 *ptrp = path[level].bp_newreq.bpr_ptr;
896
897 brelse(path[level].bp_sib_bh);
898 path[level].bp_sib_bh = NULL;
899 }
900
901 path[level + 1].bp_index++;
902 }
903
904 static void nilfs_btree_grow(struct nilfs_bmap *btree,
905 struct nilfs_btree_path *path,
906 int level, __u64 *keyp, __u64 *ptrp)
907 {
908 struct nilfs_btree_node *root, *child;
909 int n, ncblk;
910
911 root = nilfs_btree_get_root(btree);
912 child = nilfs_btree_get_sib_node(path, level);
913 ncblk = nilfs_btree_nchildren_per_block(btree);
914
915 n = nilfs_btree_node_get_nchildren(root);
916
917 nilfs_btree_node_move_right(root, child, n,
918 NILFS_BTREE_ROOT_NCHILDREN_MAX, ncblk);
919 nilfs_btree_node_set_level(root, level + 1);
920
921 if (!buffer_dirty(path[level].bp_sib_bh))
922 mark_buffer_dirty(path[level].bp_sib_bh);
923
924 path[level].bp_bh = path[level].bp_sib_bh;
925 path[level].bp_sib_bh = NULL;
926
927 nilfs_btree_do_insert(btree, path, level, keyp, ptrp);
928
929 *keyp = nilfs_btree_node_get_key(child, 0);
930 *ptrp = path[level].bp_newreq.bpr_ptr;
931 }
932
933 static __u64 nilfs_btree_find_near(const struct nilfs_bmap *btree,
934 const struct nilfs_btree_path *path)
935 {
936 struct nilfs_btree_node *node;
937 int level, ncmax;
938
939 if (path == NULL)
940 return NILFS_BMAP_INVALID_PTR;
941
942 /* left sibling */
943 level = NILFS_BTREE_LEVEL_NODE_MIN;
944 if (path[level].bp_index > 0) {
945 node = nilfs_btree_get_node(btree, path, level, &ncmax);
946 return nilfs_btree_node_get_ptr(node,
947 path[level].bp_index - 1,
948 ncmax);
949 }
950
951 /* parent */
952 level = NILFS_BTREE_LEVEL_NODE_MIN + 1;
953 if (level <= nilfs_btree_height(btree) - 1) {
954 node = nilfs_btree_get_node(btree, path, level, &ncmax);
955 return nilfs_btree_node_get_ptr(node, path[level].bp_index,
956 ncmax);
957 }
958
959 return NILFS_BMAP_INVALID_PTR;
960 }
961
962 static __u64 nilfs_btree_find_target_v(const struct nilfs_bmap *btree,
963 const struct nilfs_btree_path *path,
964 __u64 key)
965 {
966 __u64 ptr;
967
968 ptr = nilfs_bmap_find_target_seq(btree, key);
969 if (ptr != NILFS_BMAP_INVALID_PTR)
970 /* sequential access */
971 return ptr;
972 else {
973 ptr = nilfs_btree_find_near(btree, path);
974 if (ptr != NILFS_BMAP_INVALID_PTR)
975 /* near */
976 return ptr;
977 }
978 /* block group */
979 return nilfs_bmap_find_target_in_group(btree);
980 }
981
982 static int nilfs_btree_prepare_insert(struct nilfs_bmap *btree,
983 struct nilfs_btree_path *path,
984 int *levelp, __u64 key, __u64 ptr,
985 struct nilfs_bmap_stats *stats)
986 {
987 struct buffer_head *bh;
988 struct nilfs_btree_node *node, *parent, *sib;
989 __u64 sibptr;
990 int pindex, level, ncmax, ncblk, ret;
991 struct inode *dat = NULL;
992
993 stats->bs_nblocks = 0;
994 level = NILFS_BTREE_LEVEL_DATA;
995
996 /* allocate a new ptr for data block */
997 if (NILFS_BMAP_USE_VBN(btree)) {
998 path[level].bp_newreq.bpr_ptr =
999 nilfs_btree_find_target_v(btree, path, key);
1000 dat = nilfs_bmap_get_dat(btree);
1001 }
1002
1003 ret = nilfs_bmap_prepare_alloc_ptr(btree, &path[level].bp_newreq, dat);
1004 if (ret < 0)
1005 goto err_out_data;
1006
1007 ncblk = nilfs_btree_nchildren_per_block(btree);
1008
1009 for (level = NILFS_BTREE_LEVEL_NODE_MIN;
1010 level < nilfs_btree_height(btree) - 1;
1011 level++) {
1012 node = nilfs_btree_get_nonroot_node(path, level);
1013 if (nilfs_btree_node_get_nchildren(node) < ncblk) {
1014 path[level].bp_op = nilfs_btree_do_insert;
1015 stats->bs_nblocks++;
1016 goto out;
1017 }
1018
1019 parent = nilfs_btree_get_node(btree, path, level + 1, &ncmax);
1020 pindex = path[level + 1].bp_index;
1021
1022 /* left sibling */
1023 if (pindex > 0) {
1024 sibptr = nilfs_btree_node_get_ptr(parent, pindex - 1,
1025 ncmax);
1026 ret = nilfs_btree_get_block(btree, sibptr, &bh);
1027 if (ret < 0)
1028 goto err_out_child_node;
1029 sib = (struct nilfs_btree_node *)bh->b_data;
1030 if (nilfs_btree_node_get_nchildren(sib) < ncblk) {
1031 path[level].bp_sib_bh = bh;
1032 path[level].bp_op = nilfs_btree_carry_left;
1033 stats->bs_nblocks++;
1034 goto out;
1035 } else {
1036 brelse(bh);
1037 }
1038 }
1039
1040 /* right sibling */
1041 if (pindex < nilfs_btree_node_get_nchildren(parent) - 1) {
1042 sibptr = nilfs_btree_node_get_ptr(parent, pindex + 1,
1043 ncmax);
1044 ret = nilfs_btree_get_block(btree, sibptr, &bh);
1045 if (ret < 0)
1046 goto err_out_child_node;
1047 sib = (struct nilfs_btree_node *)bh->b_data;
1048 if (nilfs_btree_node_get_nchildren(sib) < ncblk) {
1049 path[level].bp_sib_bh = bh;
1050 path[level].bp_op = nilfs_btree_carry_right;
1051 stats->bs_nblocks++;
1052 goto out;
1053 } else {
1054 brelse(bh);
1055 }
1056 }
1057
1058 /* split */
1059 path[level].bp_newreq.bpr_ptr =
1060 path[level - 1].bp_newreq.bpr_ptr + 1;
1061 ret = nilfs_bmap_prepare_alloc_ptr(btree,
1062 &path[level].bp_newreq, dat);
1063 if (ret < 0)
1064 goto err_out_child_node;
1065 ret = nilfs_btree_get_new_block(btree,
1066 path[level].bp_newreq.bpr_ptr,
1067 &bh);
1068 if (ret < 0)
1069 goto err_out_curr_node;
1070
1071 stats->bs_nblocks++;
1072
1073 sib = (struct nilfs_btree_node *)bh->b_data;
1074 nilfs_btree_node_init(sib, 0, level, 0, ncblk, NULL, NULL);
1075 path[level].bp_sib_bh = bh;
1076 path[level].bp_op = nilfs_btree_split;
1077 }
1078
1079 /* root */
1080 node = nilfs_btree_get_root(btree);
1081 if (nilfs_btree_node_get_nchildren(node) <
1082 NILFS_BTREE_ROOT_NCHILDREN_MAX) {
1083 path[level].bp_op = nilfs_btree_do_insert;
1084 stats->bs_nblocks++;
1085 goto out;
1086 }
1087
1088 /* grow */
1089 path[level].bp_newreq.bpr_ptr = path[level - 1].bp_newreq.bpr_ptr + 1;
1090 ret = nilfs_bmap_prepare_alloc_ptr(btree, &path[level].bp_newreq, dat);
1091 if (ret < 0)
1092 goto err_out_child_node;
1093 ret = nilfs_btree_get_new_block(btree, path[level].bp_newreq.bpr_ptr,
1094 &bh);
1095 if (ret < 0)
1096 goto err_out_curr_node;
1097
1098 nilfs_btree_node_init((struct nilfs_btree_node *)bh->b_data,
1099 0, level, 0, ncblk, NULL, NULL);
1100 path[level].bp_sib_bh = bh;
1101 path[level].bp_op = nilfs_btree_grow;
1102
1103 level++;
1104 path[level].bp_op = nilfs_btree_do_insert;
1105
1106 /* a newly-created node block and a data block are added */
1107 stats->bs_nblocks += 2;
1108
1109 /* success */
1110 out:
1111 *levelp = level;
1112 return ret;
1113
1114 /* error */
1115 err_out_curr_node:
1116 nilfs_bmap_abort_alloc_ptr(btree, &path[level].bp_newreq, dat);
1117 err_out_child_node:
1118 for (level--; level > NILFS_BTREE_LEVEL_DATA; level--) {
1119 nilfs_btnode_delete(path[level].bp_sib_bh);
1120 nilfs_bmap_abort_alloc_ptr(btree, &path[level].bp_newreq, dat);
1121
1122 }
1123
1124 nilfs_bmap_abort_alloc_ptr(btree, &path[level].bp_newreq, dat);
1125 err_out_data:
1126 *levelp = level;
1127 stats->bs_nblocks = 0;
1128 return ret;
1129 }
1130
1131 static void nilfs_btree_commit_insert(struct nilfs_bmap *btree,
1132 struct nilfs_btree_path *path,
1133 int maxlevel, __u64 key, __u64 ptr)
1134 {
1135 struct inode *dat = NULL;
1136 int level;
1137
1138 set_buffer_nilfs_volatile((struct buffer_head *)((unsigned long)ptr));
1139 ptr = path[NILFS_BTREE_LEVEL_DATA].bp_newreq.bpr_ptr;
1140 if (NILFS_BMAP_USE_VBN(btree)) {
1141 nilfs_bmap_set_target_v(btree, key, ptr);
1142 dat = nilfs_bmap_get_dat(btree);
1143 }
1144
1145 for (level = NILFS_BTREE_LEVEL_NODE_MIN; level <= maxlevel; level++) {
1146 nilfs_bmap_commit_alloc_ptr(btree,
1147 &path[level - 1].bp_newreq, dat);
1148 path[level].bp_op(btree, path, level, &key, &ptr);
1149 }
1150
1151 if (!nilfs_bmap_dirty(btree))
1152 nilfs_bmap_set_dirty(btree);
1153 }
1154
1155 static int nilfs_btree_insert(struct nilfs_bmap *btree, __u64 key, __u64 ptr)
1156 {
1157 struct nilfs_btree_path *path;
1158 struct nilfs_bmap_stats stats;
1159 int level, ret;
1160
1161 path = nilfs_btree_alloc_path();
1162 if (path == NULL)
1163 return -ENOMEM;
1164
1165 ret = nilfs_btree_do_lookup(btree, path, key, NULL,
1166 NILFS_BTREE_LEVEL_NODE_MIN, 0);
1167 if (ret != -ENOENT) {
1168 if (ret == 0)
1169 ret = -EEXIST;
1170 goto out;
1171 }
1172
1173 ret = nilfs_btree_prepare_insert(btree, path, &level, key, ptr, &stats);
1174 if (ret < 0)
1175 goto out;
1176 nilfs_btree_commit_insert(btree, path, level, key, ptr);
1177 nilfs_inode_add_blocks(btree->b_inode, stats.bs_nblocks);
1178
1179 out:
1180 nilfs_btree_free_path(path);
1181 return ret;
1182 }
1183
1184 static void nilfs_btree_do_delete(struct nilfs_bmap *btree,
1185 struct nilfs_btree_path *path,
1186 int level, __u64 *keyp, __u64 *ptrp)
1187 {
1188 struct nilfs_btree_node *node;
1189 int ncblk;
1190
1191 if (level < nilfs_btree_height(btree) - 1) {
1192 node = nilfs_btree_get_nonroot_node(path, level);
1193 ncblk = nilfs_btree_nchildren_per_block(btree);
1194 nilfs_btree_node_delete(node, path[level].bp_index,
1195 keyp, ptrp, ncblk);
1196 if (!buffer_dirty(path[level].bp_bh))
1197 mark_buffer_dirty(path[level].bp_bh);
1198 if (path[level].bp_index == 0)
1199 nilfs_btree_promote_key(btree, path, level + 1,
1200 nilfs_btree_node_get_key(node, 0));
1201 } else {
1202 node = nilfs_btree_get_root(btree);
1203 nilfs_btree_node_delete(node, path[level].bp_index,
1204 keyp, ptrp,
1205 NILFS_BTREE_ROOT_NCHILDREN_MAX);
1206 }
1207 }
1208
1209 static void nilfs_btree_borrow_left(struct nilfs_bmap *btree,
1210 struct nilfs_btree_path *path,
1211 int level, __u64 *keyp, __u64 *ptrp)
1212 {
1213 struct nilfs_btree_node *node, *left;
1214 int nchildren, lnchildren, n, ncblk;
1215
1216 nilfs_btree_do_delete(btree, path, level, keyp, ptrp);
1217
1218 node = nilfs_btree_get_nonroot_node(path, level);
1219 left = nilfs_btree_get_sib_node(path, level);
1220 nchildren = nilfs_btree_node_get_nchildren(node);
1221 lnchildren = nilfs_btree_node_get_nchildren(left);
1222 ncblk = nilfs_btree_nchildren_per_block(btree);
1223
1224 n = (nchildren + lnchildren) / 2 - nchildren;
1225
1226 nilfs_btree_node_move_right(left, node, n, ncblk, ncblk);
1227
1228 if (!buffer_dirty(path[level].bp_bh))
1229 mark_buffer_dirty(path[level].bp_bh);
1230 if (!buffer_dirty(path[level].bp_sib_bh))
1231 mark_buffer_dirty(path[level].bp_sib_bh);
1232
1233 nilfs_btree_promote_key(btree, path, level + 1,
1234 nilfs_btree_node_get_key(node, 0));
1235
1236 brelse(path[level].bp_sib_bh);
1237 path[level].bp_sib_bh = NULL;
1238 path[level].bp_index += n;
1239 }
1240
1241 static void nilfs_btree_borrow_right(struct nilfs_bmap *btree,
1242 struct nilfs_btree_path *path,
1243 int level, __u64 *keyp, __u64 *ptrp)
1244 {
1245 struct nilfs_btree_node *node, *right;
1246 int nchildren, rnchildren, n, ncblk;
1247
1248 nilfs_btree_do_delete(btree, path, level, keyp, ptrp);
1249
1250 node = nilfs_btree_get_nonroot_node(path, level);
1251 right = nilfs_btree_get_sib_node(path, level);
1252 nchildren = nilfs_btree_node_get_nchildren(node);
1253 rnchildren = nilfs_btree_node_get_nchildren(right);
1254 ncblk = nilfs_btree_nchildren_per_block(btree);
1255
1256 n = (nchildren + rnchildren) / 2 - nchildren;
1257
1258 nilfs_btree_node_move_left(node, right, n, ncblk, ncblk);
1259
1260 if (!buffer_dirty(path[level].bp_bh))
1261 mark_buffer_dirty(path[level].bp_bh);
1262 if (!buffer_dirty(path[level].bp_sib_bh))
1263 mark_buffer_dirty(path[level].bp_sib_bh);
1264
1265 path[level + 1].bp_index++;
1266 nilfs_btree_promote_key(btree, path, level + 1,
1267 nilfs_btree_node_get_key(right, 0));
1268 path[level + 1].bp_index--;
1269
1270 brelse(path[level].bp_sib_bh);
1271 path[level].bp_sib_bh = NULL;
1272 }
1273
1274 static void nilfs_btree_concat_left(struct nilfs_bmap *btree,
1275 struct nilfs_btree_path *path,
1276 int level, __u64 *keyp, __u64 *ptrp)
1277 {
1278 struct nilfs_btree_node *node, *left;
1279 int n, ncblk;
1280
1281 nilfs_btree_do_delete(btree, path, level, keyp, ptrp);
1282
1283 node = nilfs_btree_get_nonroot_node(path, level);
1284 left = nilfs_btree_get_sib_node(path, level);
1285 ncblk = nilfs_btree_nchildren_per_block(btree);
1286
1287 n = nilfs_btree_node_get_nchildren(node);
1288
1289 nilfs_btree_node_move_left(left, node, n, ncblk, ncblk);
1290
1291 if (!buffer_dirty(path[level].bp_sib_bh))
1292 mark_buffer_dirty(path[level].bp_sib_bh);
1293
1294 nilfs_btnode_delete(path[level].bp_bh);
1295 path[level].bp_bh = path[level].bp_sib_bh;
1296 path[level].bp_sib_bh = NULL;
1297 path[level].bp_index += nilfs_btree_node_get_nchildren(left);
1298 }
1299
1300 static void nilfs_btree_concat_right(struct nilfs_bmap *btree,
1301 struct nilfs_btree_path *path,
1302 int level, __u64 *keyp, __u64 *ptrp)
1303 {
1304 struct nilfs_btree_node *node, *right;
1305 int n, ncblk;
1306
1307 nilfs_btree_do_delete(btree, path, level, keyp, ptrp);
1308
1309 node = nilfs_btree_get_nonroot_node(path, level);
1310 right = nilfs_btree_get_sib_node(path, level);
1311 ncblk = nilfs_btree_nchildren_per_block(btree);
1312
1313 n = nilfs_btree_node_get_nchildren(right);
1314
1315 nilfs_btree_node_move_left(node, right, n, ncblk, ncblk);
1316
1317 if (!buffer_dirty(path[level].bp_bh))
1318 mark_buffer_dirty(path[level].bp_bh);
1319
1320 nilfs_btnode_delete(path[level].bp_sib_bh);
1321 path[level].bp_sib_bh = NULL;
1322 path[level + 1].bp_index++;
1323 }
1324
1325 static void nilfs_btree_shrink(struct nilfs_bmap *btree,
1326 struct nilfs_btree_path *path,
1327 int level, __u64 *keyp, __u64 *ptrp)
1328 {
1329 struct nilfs_btree_node *root, *child;
1330 int n, ncblk;
1331
1332 nilfs_btree_do_delete(btree, path, level, keyp, ptrp);
1333
1334 root = nilfs_btree_get_root(btree);
1335 child = nilfs_btree_get_nonroot_node(path, level);
1336 ncblk = nilfs_btree_nchildren_per_block(btree);
1337
1338 nilfs_btree_node_delete(root, 0, NULL, NULL,
1339 NILFS_BTREE_ROOT_NCHILDREN_MAX);
1340 nilfs_btree_node_set_level(root, level);
1341 n = nilfs_btree_node_get_nchildren(child);
1342 nilfs_btree_node_move_left(root, child, n,
1343 NILFS_BTREE_ROOT_NCHILDREN_MAX, ncblk);
1344
1345 nilfs_btnode_delete(path[level].bp_bh);
1346 path[level].bp_bh = NULL;
1347 }
1348
1349 static void nilfs_btree_nop(struct nilfs_bmap *btree,
1350 struct nilfs_btree_path *path,
1351 int level, __u64 *keyp, __u64 *ptrp)
1352 {
1353 }
1354
1355 static int nilfs_btree_prepare_delete(struct nilfs_bmap *btree,
1356 struct nilfs_btree_path *path,
1357 int *levelp,
1358 struct nilfs_bmap_stats *stats,
1359 struct inode *dat)
1360 {
1361 struct buffer_head *bh;
1362 struct nilfs_btree_node *node, *parent, *sib;
1363 __u64 sibptr;
1364 int pindex, dindex, level, ncmin, ncmax, ncblk, ret;
1365
1366 ret = 0;
1367 stats->bs_nblocks = 0;
1368 ncmin = NILFS_BTREE_NODE_NCHILDREN_MIN(nilfs_btree_node_size(btree));
1369 ncblk = nilfs_btree_nchildren_per_block(btree);
1370
1371 for (level = NILFS_BTREE_LEVEL_NODE_MIN, dindex = path[level].bp_index;
1372 level < nilfs_btree_height(btree) - 1;
1373 level++) {
1374 node = nilfs_btree_get_nonroot_node(path, level);
1375 path[level].bp_oldreq.bpr_ptr =
1376 nilfs_btree_node_get_ptr(node, dindex, ncblk);
1377 ret = nilfs_bmap_prepare_end_ptr(btree,
1378 &path[level].bp_oldreq, dat);
1379 if (ret < 0)
1380 goto err_out_child_node;
1381
1382 if (nilfs_btree_node_get_nchildren(node) > ncmin) {
1383 path[level].bp_op = nilfs_btree_do_delete;
1384 stats->bs_nblocks++;
1385 goto out;
1386 }
1387
1388 parent = nilfs_btree_get_node(btree, path, level + 1, &ncmax);
1389 pindex = path[level + 1].bp_index;
1390 dindex = pindex;
1391
1392 if (pindex > 0) {
1393 /* left sibling */
1394 sibptr = nilfs_btree_node_get_ptr(parent, pindex - 1,
1395 ncmax);
1396 ret = nilfs_btree_get_block(btree, sibptr, &bh);
1397 if (ret < 0)
1398 goto err_out_curr_node;
1399 sib = (struct nilfs_btree_node *)bh->b_data;
1400 if (nilfs_btree_node_get_nchildren(sib) > ncmin) {
1401 path[level].bp_sib_bh = bh;
1402 path[level].bp_op = nilfs_btree_borrow_left;
1403 stats->bs_nblocks++;
1404 goto out;
1405 } else {
1406 path[level].bp_sib_bh = bh;
1407 path[level].bp_op = nilfs_btree_concat_left;
1408 stats->bs_nblocks++;
1409 /* continue; */
1410 }
1411 } else if (pindex <
1412 nilfs_btree_node_get_nchildren(parent) - 1) {
1413 /* right sibling */
1414 sibptr = nilfs_btree_node_get_ptr(parent, pindex + 1,
1415 ncmax);
1416 ret = nilfs_btree_get_block(btree, sibptr, &bh);
1417 if (ret < 0)
1418 goto err_out_curr_node;
1419 sib = (struct nilfs_btree_node *)bh->b_data;
1420 if (nilfs_btree_node_get_nchildren(sib) > ncmin) {
1421 path[level].bp_sib_bh = bh;
1422 path[level].bp_op = nilfs_btree_borrow_right;
1423 stats->bs_nblocks++;
1424 goto out;
1425 } else {
1426 path[level].bp_sib_bh = bh;
1427 path[level].bp_op = nilfs_btree_concat_right;
1428 stats->bs_nblocks++;
1429 /*
1430 * When merging right sibling node
1431 * into the current node, pointer to
1432 * the right sibling node must be
1433 * terminated instead. The adjustment
1434 * below is required for that.
1435 */
1436 dindex = pindex + 1;
1437 /* continue; */
1438 }
1439 } else {
1440 /* no siblings */
1441 /* the only child of the root node */
1442 WARN_ON(level != nilfs_btree_height(btree) - 2);
1443 if (nilfs_btree_node_get_nchildren(node) - 1 <=
1444 NILFS_BTREE_ROOT_NCHILDREN_MAX) {
1445 path[level].bp_op = nilfs_btree_shrink;
1446 stats->bs_nblocks += 2;
1447 level++;
1448 path[level].bp_op = nilfs_btree_nop;
1449 goto shrink_root_child;
1450 } else {
1451 path[level].bp_op = nilfs_btree_do_delete;
1452 stats->bs_nblocks++;
1453 goto out;
1454 }
1455 }
1456 }
1457
1458 /* child of the root node is deleted */
1459 path[level].bp_op = nilfs_btree_do_delete;
1460 stats->bs_nblocks++;
1461
1462 shrink_root_child:
1463 node = nilfs_btree_get_root(btree);
1464 path[level].bp_oldreq.bpr_ptr =
1465 nilfs_btree_node_get_ptr(node, dindex,
1466 NILFS_BTREE_ROOT_NCHILDREN_MAX);
1467
1468 ret = nilfs_bmap_prepare_end_ptr(btree, &path[level].bp_oldreq, dat);
1469 if (ret < 0)
1470 goto err_out_child_node;
1471
1472 /* success */
1473 out:
1474 *levelp = level;
1475 return ret;
1476
1477 /* error */
1478 err_out_curr_node:
1479 nilfs_bmap_abort_end_ptr(btree, &path[level].bp_oldreq, dat);
1480 err_out_child_node:
1481 for (level--; level >= NILFS_BTREE_LEVEL_NODE_MIN; level--) {
1482 brelse(path[level].bp_sib_bh);
1483 nilfs_bmap_abort_end_ptr(btree, &path[level].bp_oldreq, dat);
1484 }
1485 *levelp = level;
1486 stats->bs_nblocks = 0;
1487 return ret;
1488 }
1489
1490 static void nilfs_btree_commit_delete(struct nilfs_bmap *btree,
1491 struct nilfs_btree_path *path,
1492 int maxlevel, struct inode *dat)
1493 {
1494 int level;
1495
1496 for (level = NILFS_BTREE_LEVEL_NODE_MIN; level <= maxlevel; level++) {
1497 nilfs_bmap_commit_end_ptr(btree, &path[level].bp_oldreq, dat);
1498 path[level].bp_op(btree, path, level, NULL, NULL);
1499 }
1500
1501 if (!nilfs_bmap_dirty(btree))
1502 nilfs_bmap_set_dirty(btree);
1503 }
1504
1505 static int nilfs_btree_delete(struct nilfs_bmap *btree, __u64 key)
1506
1507 {
1508 struct nilfs_btree_path *path;
1509 struct nilfs_bmap_stats stats;
1510 struct inode *dat;
1511 int level, ret;
1512
1513 path = nilfs_btree_alloc_path();
1514 if (path == NULL)
1515 return -ENOMEM;
1516
1517 ret = nilfs_btree_do_lookup(btree, path, key, NULL,
1518 NILFS_BTREE_LEVEL_NODE_MIN, 0);
1519 if (ret < 0)
1520 goto out;
1521
1522
1523 dat = NILFS_BMAP_USE_VBN(btree) ? nilfs_bmap_get_dat(btree) : NULL;
1524
1525 ret = nilfs_btree_prepare_delete(btree, path, &level, &stats, dat);
1526 if (ret < 0)
1527 goto out;
1528 nilfs_btree_commit_delete(btree, path, level, dat);
1529 nilfs_inode_sub_blocks(btree->b_inode, stats.bs_nblocks);
1530
1531 out:
1532 nilfs_btree_free_path(path);
1533 return ret;
1534 }
1535
1536 static int nilfs_btree_last_key(const struct nilfs_bmap *btree, __u64 *keyp)
1537 {
1538 struct nilfs_btree_path *path;
1539 int ret;
1540
1541 path = nilfs_btree_alloc_path();
1542 if (path == NULL)
1543 return -ENOMEM;
1544
1545 ret = nilfs_btree_do_lookup_last(btree, path, keyp, NULL);
1546
1547 nilfs_btree_free_path(path);
1548
1549 return ret;
1550 }
1551
1552 static int nilfs_btree_check_delete(struct nilfs_bmap *btree, __u64 key)
1553 {
1554 struct buffer_head *bh;
1555 struct nilfs_btree_node *root, *node;
1556 __u64 maxkey, nextmaxkey;
1557 __u64 ptr;
1558 int nchildren, ret;
1559
1560 root = nilfs_btree_get_root(btree);
1561 switch (nilfs_btree_height(btree)) {
1562 case 2:
1563 bh = NULL;
1564 node = root;
1565 break;
1566 case 3:
1567 nchildren = nilfs_btree_node_get_nchildren(root);
1568 if (nchildren > 1)
1569 return 0;
1570 ptr = nilfs_btree_node_get_ptr(root, nchildren - 1,
1571 NILFS_BTREE_ROOT_NCHILDREN_MAX);
1572 ret = nilfs_btree_get_block(btree, ptr, &bh);
1573 if (ret < 0)
1574 return ret;
1575 node = (struct nilfs_btree_node *)bh->b_data;
1576 break;
1577 default:
1578 return 0;
1579 }
1580
1581 nchildren = nilfs_btree_node_get_nchildren(node);
1582 maxkey = nilfs_btree_node_get_key(node, nchildren - 1);
1583 nextmaxkey = (nchildren > 1) ?
1584 nilfs_btree_node_get_key(node, nchildren - 2) : 0;
1585 if (bh != NULL)
1586 brelse(bh);
1587
1588 return (maxkey == key) && (nextmaxkey < NILFS_BMAP_LARGE_LOW);
1589 }
1590
1591 static int nilfs_btree_gather_data(struct nilfs_bmap *btree,
1592 __u64 *keys, __u64 *ptrs, int nitems)
1593 {
1594 struct buffer_head *bh;
1595 struct nilfs_btree_node *node, *root;
1596 __le64 *dkeys;
1597 __le64 *dptrs;
1598 __u64 ptr;
1599 int nchildren, ncmax, i, ret;
1600
1601 root = nilfs_btree_get_root(btree);
1602 switch (nilfs_btree_height(btree)) {
1603 case 2:
1604 bh = NULL;
1605 node = root;
1606 ncmax = NILFS_BTREE_ROOT_NCHILDREN_MAX;
1607 break;
1608 case 3:
1609 nchildren = nilfs_btree_node_get_nchildren(root);
1610 WARN_ON(nchildren > 1);
1611 ptr = nilfs_btree_node_get_ptr(root, nchildren - 1,
1612 NILFS_BTREE_ROOT_NCHILDREN_MAX);
1613 ret = nilfs_btree_get_block(btree, ptr, &bh);
1614 if (ret < 0)
1615 return ret;
1616 node = (struct nilfs_btree_node *)bh->b_data;
1617 ncmax = nilfs_btree_nchildren_per_block(btree);
1618 break;
1619 default:
1620 node = NULL;
1621 return -EINVAL;
1622 }
1623
1624 nchildren = nilfs_btree_node_get_nchildren(node);
1625 if (nchildren < nitems)
1626 nitems = nchildren;
1627 dkeys = nilfs_btree_node_dkeys(node);
1628 dptrs = nilfs_btree_node_dptrs(node, ncmax);
1629 for (i = 0; i < nitems; i++) {
1630 keys[i] = le64_to_cpu(dkeys[i]);
1631 ptrs[i] = le64_to_cpu(dptrs[i]);
1632 }
1633
1634 if (bh != NULL)
1635 brelse(bh);
1636
1637 return nitems;
1638 }
1639
1640 static int
1641 nilfs_btree_prepare_convert_and_insert(struct nilfs_bmap *btree, __u64 key,
1642 union nilfs_bmap_ptr_req *dreq,
1643 union nilfs_bmap_ptr_req *nreq,
1644 struct buffer_head **bhp,
1645 struct nilfs_bmap_stats *stats)
1646 {
1647 struct buffer_head *bh;
1648 struct inode *dat = NULL;
1649 int ret;
1650
1651 stats->bs_nblocks = 0;
1652
1653 /* for data */
1654 /* cannot find near ptr */
1655 if (NILFS_BMAP_USE_VBN(btree)) {
1656 dreq->bpr_ptr = nilfs_btree_find_target_v(btree, NULL, key);
1657 dat = nilfs_bmap_get_dat(btree);
1658 }
1659
1660 ret = nilfs_bmap_prepare_alloc_ptr(btree, dreq, dat);
1661 if (ret < 0)
1662 return ret;
1663
1664 *bhp = NULL;
1665 stats->bs_nblocks++;
1666 if (nreq != NULL) {
1667 nreq->bpr_ptr = dreq->bpr_ptr + 1;
1668 ret = nilfs_bmap_prepare_alloc_ptr(btree, nreq, dat);
1669 if (ret < 0)
1670 goto err_out_dreq;
1671
1672 ret = nilfs_btree_get_new_block(btree, nreq->bpr_ptr, &bh);
1673 if (ret < 0)
1674 goto err_out_nreq;
1675
1676 *bhp = bh;
1677 stats->bs_nblocks++;
1678 }
1679
1680 /* success */
1681 return 0;
1682
1683 /* error */
1684 err_out_nreq:
1685 nilfs_bmap_abort_alloc_ptr(btree, nreq, dat);
1686 err_out_dreq:
1687 nilfs_bmap_abort_alloc_ptr(btree, dreq, dat);
1688 stats->bs_nblocks = 0;
1689 return ret;
1690
1691 }
1692
1693 static void
1694 nilfs_btree_commit_convert_and_insert(struct nilfs_bmap *btree,
1695 __u64 key, __u64 ptr,
1696 const __u64 *keys, const __u64 *ptrs,
1697 int n,
1698 union nilfs_bmap_ptr_req *dreq,
1699 union nilfs_bmap_ptr_req *nreq,
1700 struct buffer_head *bh)
1701 {
1702 struct nilfs_btree_node *node;
1703 struct inode *dat;
1704 __u64 tmpptr;
1705 int ncblk;
1706
1707 /* free resources */
1708 if (btree->b_ops->bop_clear != NULL)
1709 btree->b_ops->bop_clear(btree);
1710
1711 /* ptr must be a pointer to a buffer head. */
1712 set_buffer_nilfs_volatile((struct buffer_head *)((unsigned long)ptr));
1713
1714 /* convert and insert */
1715 dat = NILFS_BMAP_USE_VBN(btree) ? nilfs_bmap_get_dat(btree) : NULL;
1716 nilfs_btree_init(btree);
1717 if (nreq != NULL) {
1718 nilfs_bmap_commit_alloc_ptr(btree, dreq, dat);
1719 nilfs_bmap_commit_alloc_ptr(btree, nreq, dat);
1720
1721 /* create child node at level 1 */
1722 node = (struct nilfs_btree_node *)bh->b_data;
1723 ncblk = nilfs_btree_nchildren_per_block(btree);
1724 nilfs_btree_node_init(node, 0, 1, n, ncblk, keys, ptrs);
1725 nilfs_btree_node_insert(node, n, key, dreq->bpr_ptr, ncblk);
1726 if (!buffer_dirty(bh))
1727 mark_buffer_dirty(bh);
1728 if (!nilfs_bmap_dirty(btree))
1729 nilfs_bmap_set_dirty(btree);
1730
1731 brelse(bh);
1732
1733 /* create root node at level 2 */
1734 node = nilfs_btree_get_root(btree);
1735 tmpptr = nreq->bpr_ptr;
1736 nilfs_btree_node_init(node, NILFS_BTREE_NODE_ROOT, 2, 1,
1737 NILFS_BTREE_ROOT_NCHILDREN_MAX,
1738 &keys[0], &tmpptr);
1739 } else {
1740 nilfs_bmap_commit_alloc_ptr(btree, dreq, dat);
1741
1742 /* create root node at level 1 */
1743 node = nilfs_btree_get_root(btree);
1744 nilfs_btree_node_init(node, NILFS_BTREE_NODE_ROOT, 1, n,
1745 NILFS_BTREE_ROOT_NCHILDREN_MAX,
1746 keys, ptrs);
1747 nilfs_btree_node_insert(node, n, key, dreq->bpr_ptr,
1748 NILFS_BTREE_ROOT_NCHILDREN_MAX);
1749 if (!nilfs_bmap_dirty(btree))
1750 nilfs_bmap_set_dirty(btree);
1751 }
1752
1753 if (NILFS_BMAP_USE_VBN(btree))
1754 nilfs_bmap_set_target_v(btree, key, dreq->bpr_ptr);
1755 }
1756
1757 /**
1758 * nilfs_btree_convert_and_insert -
1759 * @bmap:
1760 * @key:
1761 * @ptr:
1762 * @keys:
1763 * @ptrs:
1764 * @n:
1765 */
1766 int nilfs_btree_convert_and_insert(struct nilfs_bmap *btree,
1767 __u64 key, __u64 ptr,
1768 const __u64 *keys, const __u64 *ptrs, int n)
1769 {
1770 struct buffer_head *bh;
1771 union nilfs_bmap_ptr_req dreq, nreq, *di, *ni;
1772 struct nilfs_bmap_stats stats;
1773 int ret;
1774
1775 if (n + 1 <= NILFS_BTREE_ROOT_NCHILDREN_MAX) {
1776 di = &dreq;
1777 ni = NULL;
1778 } else if ((n + 1) <= NILFS_BTREE_NODE_NCHILDREN_MAX(
1779 1 << btree->b_inode->i_blkbits)) {
1780 di = &dreq;
1781 ni = &nreq;
1782 } else {
1783 di = NULL;
1784 ni = NULL;
1785 BUG();
1786 }
1787
1788 ret = nilfs_btree_prepare_convert_and_insert(btree, key, di, ni, &bh,
1789 &stats);
1790 if (ret < 0)
1791 return ret;
1792 nilfs_btree_commit_convert_and_insert(btree, key, ptr, keys, ptrs, n,
1793 di, ni, bh);
1794 nilfs_inode_add_blocks(btree->b_inode, stats.bs_nblocks);
1795 return 0;
1796 }
1797
1798 static int nilfs_btree_propagate_p(struct nilfs_bmap *btree,
1799 struct nilfs_btree_path *path,
1800 int level,
1801 struct buffer_head *bh)
1802 {
1803 while ((++level < nilfs_btree_height(btree) - 1) &&
1804 !buffer_dirty(path[level].bp_bh))
1805 mark_buffer_dirty(path[level].bp_bh);
1806
1807 return 0;
1808 }
1809
1810 static int nilfs_btree_prepare_update_v(struct nilfs_bmap *btree,
1811 struct nilfs_btree_path *path,
1812 int level, struct inode *dat)
1813 {
1814 struct nilfs_btree_node *parent;
1815 int ncmax, ret;
1816
1817 parent = nilfs_btree_get_node(btree, path, level + 1, &ncmax);
1818 path[level].bp_oldreq.bpr_ptr =
1819 nilfs_btree_node_get_ptr(parent, path[level + 1].bp_index,
1820 ncmax);
1821 path[level].bp_newreq.bpr_ptr = path[level].bp_oldreq.bpr_ptr + 1;
1822 ret = nilfs_dat_prepare_update(dat, &path[level].bp_oldreq.bpr_req,
1823 &path[level].bp_newreq.bpr_req);
1824 if (ret < 0)
1825 return ret;
1826
1827 if (buffer_nilfs_node(path[level].bp_bh)) {
1828 path[level].bp_ctxt.oldkey = path[level].bp_oldreq.bpr_ptr;
1829 path[level].bp_ctxt.newkey = path[level].bp_newreq.bpr_ptr;
1830 path[level].bp_ctxt.bh = path[level].bp_bh;
1831 ret = nilfs_btnode_prepare_change_key(
1832 &NILFS_BMAP_I(btree)->i_btnode_cache,
1833 &path[level].bp_ctxt);
1834 if (ret < 0) {
1835 nilfs_dat_abort_update(dat,
1836 &path[level].bp_oldreq.bpr_req,
1837 &path[level].bp_newreq.bpr_req);
1838 return ret;
1839 }
1840 }
1841
1842 return 0;
1843 }
1844
1845 static void nilfs_btree_commit_update_v(struct nilfs_bmap *btree,
1846 struct nilfs_btree_path *path,
1847 int level, struct inode *dat)
1848 {
1849 struct nilfs_btree_node *parent;
1850 int ncmax;
1851
1852 nilfs_dat_commit_update(dat, &path[level].bp_oldreq.bpr_req,
1853 &path[level].bp_newreq.bpr_req,
1854 btree->b_ptr_type == NILFS_BMAP_PTR_VS);
1855
1856 if (buffer_nilfs_node(path[level].bp_bh)) {
1857 nilfs_btnode_commit_change_key(
1858 &NILFS_BMAP_I(btree)->i_btnode_cache,
1859 &path[level].bp_ctxt);
1860 path[level].bp_bh = path[level].bp_ctxt.bh;
1861 }
1862 set_buffer_nilfs_volatile(path[level].bp_bh);
1863
1864 parent = nilfs_btree_get_node(btree, path, level + 1, &ncmax);
1865 nilfs_btree_node_set_ptr(parent, path[level + 1].bp_index,
1866 path[level].bp_newreq.bpr_ptr, ncmax);
1867 }
1868
1869 static void nilfs_btree_abort_update_v(struct nilfs_bmap *btree,
1870 struct nilfs_btree_path *path,
1871 int level, struct inode *dat)
1872 {
1873 nilfs_dat_abort_update(dat, &path[level].bp_oldreq.bpr_req,
1874 &path[level].bp_newreq.bpr_req);
1875 if (buffer_nilfs_node(path[level].bp_bh))
1876 nilfs_btnode_abort_change_key(
1877 &NILFS_BMAP_I(btree)->i_btnode_cache,
1878 &path[level].bp_ctxt);
1879 }
1880
1881 static int nilfs_btree_prepare_propagate_v(struct nilfs_bmap *btree,
1882 struct nilfs_btree_path *path,
1883 int minlevel, int *maxlevelp,
1884 struct inode *dat)
1885 {
1886 int level, ret;
1887
1888 level = minlevel;
1889 if (!buffer_nilfs_volatile(path[level].bp_bh)) {
1890 ret = nilfs_btree_prepare_update_v(btree, path, level, dat);
1891 if (ret < 0)
1892 return ret;
1893 }
1894 while ((++level < nilfs_btree_height(btree) - 1) &&
1895 !buffer_dirty(path[level].bp_bh)) {
1896
1897 WARN_ON(buffer_nilfs_volatile(path[level].bp_bh));
1898 ret = nilfs_btree_prepare_update_v(btree, path, level, dat);
1899 if (ret < 0)
1900 goto out;
1901 }
1902
1903 /* success */
1904 *maxlevelp = level - 1;
1905 return 0;
1906
1907 /* error */
1908 out:
1909 while (--level > minlevel)
1910 nilfs_btree_abort_update_v(btree, path, level, dat);
1911 if (!buffer_nilfs_volatile(path[level].bp_bh))
1912 nilfs_btree_abort_update_v(btree, path, level, dat);
1913 return ret;
1914 }
1915
1916 static void nilfs_btree_commit_propagate_v(struct nilfs_bmap *btree,
1917 struct nilfs_btree_path *path,
1918 int minlevel, int maxlevel,
1919 struct buffer_head *bh,
1920 struct inode *dat)
1921 {
1922 int level;
1923
1924 if (!buffer_nilfs_volatile(path[minlevel].bp_bh))
1925 nilfs_btree_commit_update_v(btree, path, minlevel, dat);
1926
1927 for (level = minlevel + 1; level <= maxlevel; level++)
1928 nilfs_btree_commit_update_v(btree, path, level, dat);
1929 }
1930
1931 static int nilfs_btree_propagate_v(struct nilfs_bmap *btree,
1932 struct nilfs_btree_path *path,
1933 int level, struct buffer_head *bh)
1934 {
1935 int maxlevel = 0, ret;
1936 struct nilfs_btree_node *parent;
1937 struct inode *dat = nilfs_bmap_get_dat(btree);
1938 __u64 ptr;
1939 int ncmax;
1940
1941 get_bh(bh);
1942 path[level].bp_bh = bh;
1943 ret = nilfs_btree_prepare_propagate_v(btree, path, level, &maxlevel,
1944 dat);
1945 if (ret < 0)
1946 goto out;
1947
1948 if (buffer_nilfs_volatile(path[level].bp_bh)) {
1949 parent = nilfs_btree_get_node(btree, path, level + 1, &ncmax);
1950 ptr = nilfs_btree_node_get_ptr(parent,
1951 path[level + 1].bp_index,
1952 ncmax);
1953 ret = nilfs_dat_mark_dirty(dat, ptr);
1954 if (ret < 0)
1955 goto out;
1956 }
1957
1958 nilfs_btree_commit_propagate_v(btree, path, level, maxlevel, bh, dat);
1959
1960 out:
1961 brelse(path[level].bp_bh);
1962 path[level].bp_bh = NULL;
1963 return ret;
1964 }
1965
1966 static int nilfs_btree_propagate(struct nilfs_bmap *btree,
1967 struct buffer_head *bh)
1968 {
1969 struct nilfs_btree_path *path;
1970 struct nilfs_btree_node *node;
1971 __u64 key;
1972 int level, ret;
1973
1974 WARN_ON(!buffer_dirty(bh));
1975
1976 path = nilfs_btree_alloc_path();
1977 if (path == NULL)
1978 return -ENOMEM;
1979
1980 if (buffer_nilfs_node(bh)) {
1981 node = (struct nilfs_btree_node *)bh->b_data;
1982 key = nilfs_btree_node_get_key(node, 0);
1983 level = nilfs_btree_node_get_level(node);
1984 } else {
1985 key = nilfs_bmap_data_get_key(btree, bh);
1986 level = NILFS_BTREE_LEVEL_DATA;
1987 }
1988
1989 ret = nilfs_btree_do_lookup(btree, path, key, NULL, level + 1, 0);
1990 if (ret < 0) {
1991 if (unlikely(ret == -ENOENT))
1992 printk(KERN_CRIT "%s: key = %llu, level == %d\n",
1993 __func__, (unsigned long long)key, level);
1994 goto out;
1995 }
1996
1997 ret = NILFS_BMAP_USE_VBN(btree) ?
1998 nilfs_btree_propagate_v(btree, path, level, bh) :
1999 nilfs_btree_propagate_p(btree, path, level, bh);
2000
2001 out:
2002 nilfs_btree_free_path(path);
2003
2004 return ret;
2005 }
2006
2007 static int nilfs_btree_propagate_gc(struct nilfs_bmap *btree,
2008 struct buffer_head *bh)
2009 {
2010 return nilfs_dat_mark_dirty(nilfs_bmap_get_dat(btree), bh->b_blocknr);
2011 }
2012
2013 static void nilfs_btree_add_dirty_buffer(struct nilfs_bmap *btree,
2014 struct list_head *lists,
2015 struct buffer_head *bh)
2016 {
2017 struct list_head *head;
2018 struct buffer_head *cbh;
2019 struct nilfs_btree_node *node, *cnode;
2020 __u64 key, ckey;
2021 int level;
2022
2023 get_bh(bh);
2024 node = (struct nilfs_btree_node *)bh->b_data;
2025 key = nilfs_btree_node_get_key(node, 0);
2026 level = nilfs_btree_node_get_level(node);
2027 if (level < NILFS_BTREE_LEVEL_NODE_MIN ||
2028 level >= NILFS_BTREE_LEVEL_MAX) {
2029 dump_stack();
2030 printk(KERN_WARNING
2031 "%s: invalid btree level: %d (key=%llu, ino=%lu, "
2032 "blocknr=%llu)\n",
2033 __func__, level, (unsigned long long)key,
2034 NILFS_BMAP_I(btree)->vfs_inode.i_ino,
2035 (unsigned long long)bh->b_blocknr);
2036 return;
2037 }
2038
2039 list_for_each(head, &lists[level]) {
2040 cbh = list_entry(head, struct buffer_head, b_assoc_buffers);
2041 cnode = (struct nilfs_btree_node *)cbh->b_data;
2042 ckey = nilfs_btree_node_get_key(cnode, 0);
2043 if (key < ckey)
2044 break;
2045 }
2046 list_add_tail(&bh->b_assoc_buffers, head);
2047 }
2048
2049 static void nilfs_btree_lookup_dirty_buffers(struct nilfs_bmap *btree,
2050 struct list_head *listp)
2051 {
2052 struct address_space *btcache = &NILFS_BMAP_I(btree)->i_btnode_cache;
2053 struct list_head lists[NILFS_BTREE_LEVEL_MAX];
2054 struct pagevec pvec;
2055 struct buffer_head *bh, *head;
2056 pgoff_t index = 0;
2057 int level, i;
2058
2059 for (level = NILFS_BTREE_LEVEL_NODE_MIN;
2060 level < NILFS_BTREE_LEVEL_MAX;
2061 level++)
2062 INIT_LIST_HEAD(&lists[level]);
2063
2064 pagevec_init(&pvec, 0);
2065
2066 while (pagevec_lookup_tag(&pvec, btcache, &index, PAGECACHE_TAG_DIRTY,
2067 PAGEVEC_SIZE)) {
2068 for (i = 0; i < pagevec_count(&pvec); i++) {
2069 bh = head = page_buffers(pvec.pages[i]);
2070 do {
2071 if (buffer_dirty(bh))
2072 nilfs_btree_add_dirty_buffer(btree,
2073 lists, bh);
2074 } while ((bh = bh->b_this_page) != head);
2075 }
2076 pagevec_release(&pvec);
2077 cond_resched();
2078 }
2079
2080 for (level = NILFS_BTREE_LEVEL_NODE_MIN;
2081 level < NILFS_BTREE_LEVEL_MAX;
2082 level++)
2083 list_splice_tail(&lists[level], listp);
2084 }
2085
2086 static int nilfs_btree_assign_p(struct nilfs_bmap *btree,
2087 struct nilfs_btree_path *path,
2088 int level,
2089 struct buffer_head **bh,
2090 sector_t blocknr,
2091 union nilfs_binfo *binfo)
2092 {
2093 struct nilfs_btree_node *parent;
2094 __u64 key;
2095 __u64 ptr;
2096 int ncmax, ret;
2097
2098 parent = nilfs_btree_get_node(btree, path, level + 1, &ncmax);
2099 ptr = nilfs_btree_node_get_ptr(parent, path[level + 1].bp_index,
2100 ncmax);
2101 if (buffer_nilfs_node(*bh)) {
2102 path[level].bp_ctxt.oldkey = ptr;
2103 path[level].bp_ctxt.newkey = blocknr;
2104 path[level].bp_ctxt.bh = *bh;
2105 ret = nilfs_btnode_prepare_change_key(
2106 &NILFS_BMAP_I(btree)->i_btnode_cache,
2107 &path[level].bp_ctxt);
2108 if (ret < 0)
2109 return ret;
2110 nilfs_btnode_commit_change_key(
2111 &NILFS_BMAP_I(btree)->i_btnode_cache,
2112 &path[level].bp_ctxt);
2113 *bh = path[level].bp_ctxt.bh;
2114 }
2115
2116 nilfs_btree_node_set_ptr(parent, path[level + 1].bp_index, blocknr,
2117 ncmax);
2118
2119 key = nilfs_btree_node_get_key(parent, path[level + 1].bp_index);
2120 /* on-disk format */
2121 binfo->bi_dat.bi_blkoff = cpu_to_le64(key);
2122 binfo->bi_dat.bi_level = level;
2123
2124 return 0;
2125 }
2126
2127 static int nilfs_btree_assign_v(struct nilfs_bmap *btree,
2128 struct nilfs_btree_path *path,
2129 int level,
2130 struct buffer_head **bh,
2131 sector_t blocknr,
2132 union nilfs_binfo *binfo)
2133 {
2134 struct nilfs_btree_node *parent;
2135 struct inode *dat = nilfs_bmap_get_dat(btree);
2136 __u64 key;
2137 __u64 ptr;
2138 union nilfs_bmap_ptr_req req;
2139 int ncmax, ret;
2140
2141 parent = nilfs_btree_get_node(btree, path, level + 1, &ncmax);
2142 ptr = nilfs_btree_node_get_ptr(parent, path[level + 1].bp_index,
2143 ncmax);
2144 req.bpr_ptr = ptr;
2145 ret = nilfs_dat_prepare_start(dat, &req.bpr_req);
2146 if (ret < 0)
2147 return ret;
2148 nilfs_dat_commit_start(dat, &req.bpr_req, blocknr);
2149
2150 key = nilfs_btree_node_get_key(parent, path[level + 1].bp_index);
2151 /* on-disk format */
2152 binfo->bi_v.bi_vblocknr = cpu_to_le64(ptr);
2153 binfo->bi_v.bi_blkoff = cpu_to_le64(key);
2154
2155 return 0;
2156 }
2157
2158 static int nilfs_btree_assign(struct nilfs_bmap *btree,
2159 struct buffer_head **bh,
2160 sector_t blocknr,
2161 union nilfs_binfo *binfo)
2162 {
2163 struct nilfs_btree_path *path;
2164 struct nilfs_btree_node *node;
2165 __u64 key;
2166 int level, ret;
2167
2168 path = nilfs_btree_alloc_path();
2169 if (path == NULL)
2170 return -ENOMEM;
2171
2172 if (buffer_nilfs_node(*bh)) {
2173 node = (struct nilfs_btree_node *)(*bh)->b_data;
2174 key = nilfs_btree_node_get_key(node, 0);
2175 level = nilfs_btree_node_get_level(node);
2176 } else {
2177 key = nilfs_bmap_data_get_key(btree, *bh);
2178 level = NILFS_BTREE_LEVEL_DATA;
2179 }
2180
2181 ret = nilfs_btree_do_lookup(btree, path, key, NULL, level + 1, 0);
2182 if (ret < 0) {
2183 WARN_ON(ret == -ENOENT);
2184 goto out;
2185 }
2186
2187 ret = NILFS_BMAP_USE_VBN(btree) ?
2188 nilfs_btree_assign_v(btree, path, level, bh, blocknr, binfo) :
2189 nilfs_btree_assign_p(btree, path, level, bh, blocknr, binfo);
2190
2191 out:
2192 nilfs_btree_free_path(path);
2193
2194 return ret;
2195 }
2196
2197 static int nilfs_btree_assign_gc(struct nilfs_bmap *btree,
2198 struct buffer_head **bh,
2199 sector_t blocknr,
2200 union nilfs_binfo *binfo)
2201 {
2202 struct nilfs_btree_node *node;
2203 __u64 key;
2204 int ret;
2205
2206 ret = nilfs_dat_move(nilfs_bmap_get_dat(btree), (*bh)->b_blocknr,
2207 blocknr);
2208 if (ret < 0)
2209 return ret;
2210
2211 if (buffer_nilfs_node(*bh)) {
2212 node = (struct nilfs_btree_node *)(*bh)->b_data;
2213 key = nilfs_btree_node_get_key(node, 0);
2214 } else
2215 key = nilfs_bmap_data_get_key(btree, *bh);
2216
2217 /* on-disk format */
2218 binfo->bi_v.bi_vblocknr = cpu_to_le64((*bh)->b_blocknr);
2219 binfo->bi_v.bi_blkoff = cpu_to_le64(key);
2220
2221 return 0;
2222 }
2223
2224 static int nilfs_btree_mark(struct nilfs_bmap *btree, __u64 key, int level)
2225 {
2226 struct buffer_head *bh;
2227 struct nilfs_btree_path *path;
2228 __u64 ptr;
2229 int ret;
2230
2231 path = nilfs_btree_alloc_path();
2232 if (path == NULL)
2233 return -ENOMEM;
2234
2235 ret = nilfs_btree_do_lookup(btree, path, key, &ptr, level + 1, 0);
2236 if (ret < 0) {
2237 WARN_ON(ret == -ENOENT);
2238 goto out;
2239 }
2240 ret = nilfs_btree_get_block(btree, ptr, &bh);
2241 if (ret < 0) {
2242 WARN_ON(ret == -ENOENT);
2243 goto out;
2244 }
2245
2246 if (!buffer_dirty(bh))
2247 mark_buffer_dirty(bh);
2248 brelse(bh);
2249 if (!nilfs_bmap_dirty(btree))
2250 nilfs_bmap_set_dirty(btree);
2251
2252 out:
2253 nilfs_btree_free_path(path);
2254 return ret;
2255 }
2256
2257 static const struct nilfs_bmap_operations nilfs_btree_ops = {
2258 .bop_lookup = nilfs_btree_lookup,
2259 .bop_lookup_contig = nilfs_btree_lookup_contig,
2260 .bop_insert = nilfs_btree_insert,
2261 .bop_delete = nilfs_btree_delete,
2262 .bop_clear = NULL,
2263
2264 .bop_propagate = nilfs_btree_propagate,
2265
2266 .bop_lookup_dirty_buffers = nilfs_btree_lookup_dirty_buffers,
2267
2268 .bop_assign = nilfs_btree_assign,
2269 .bop_mark = nilfs_btree_mark,
2270
2271 .bop_last_key = nilfs_btree_last_key,
2272 .bop_check_insert = NULL,
2273 .bop_check_delete = nilfs_btree_check_delete,
2274 .bop_gather_data = nilfs_btree_gather_data,
2275 };
2276
2277 static const struct nilfs_bmap_operations nilfs_btree_ops_gc = {
2278 .bop_lookup = NULL,
2279 .bop_lookup_contig = NULL,
2280 .bop_insert = NULL,
2281 .bop_delete = NULL,
2282 .bop_clear = NULL,
2283
2284 .bop_propagate = nilfs_btree_propagate_gc,
2285
2286 .bop_lookup_dirty_buffers = nilfs_btree_lookup_dirty_buffers,
2287
2288 .bop_assign = nilfs_btree_assign_gc,
2289 .bop_mark = NULL,
2290
2291 .bop_last_key = NULL,
2292 .bop_check_insert = NULL,
2293 .bop_check_delete = NULL,
2294 .bop_gather_data = NULL,
2295 };
2296
2297 int nilfs_btree_init(struct nilfs_bmap *bmap)
2298 {
2299 bmap->b_ops = &nilfs_btree_ops;
2300 bmap->b_nchildren_per_block =
2301 NILFS_BTREE_NODE_NCHILDREN_MAX(nilfs_btree_node_size(bmap));
2302 return 0;
2303 }
2304
2305 void nilfs_btree_init_gc(struct nilfs_bmap *bmap)
2306 {
2307 bmap->b_ops = &nilfs_btree_ops_gc;
2308 bmap->b_nchildren_per_block =
2309 NILFS_BTREE_NODE_NCHILDREN_MAX(nilfs_btree_node_size(bmap));
2310 }
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