2 * btree.c - NILFS B-tree.
4 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
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.
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.
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
20 * Written by Koji Sato <koji@osrg.net>.
23 #include <linux/slab.h>
24 #include <linux/string.h>
25 #include <linux/errno.h>
26 #include <linux/pagevec.h>
34 * struct nilfs_btree_path - A path on which B-tree operations are executed
35 * @bp_bh: buffer head of node block
36 * @bp_sib_bh: buffer head of sibling node block
37 * @bp_index: index of child node
38 * @bp_oldreq: ptr end request for old ptr
39 * @bp_newreq: ptr alloc request for new ptr
40 * @bp_op: rebalance operation
42 struct nilfs_btree_path {
43 struct buffer_head *bp_bh;
44 struct buffer_head *bp_sib_bh;
46 union nilfs_bmap_ptr_req bp_oldreq;
47 union nilfs_bmap_ptr_req bp_newreq;
48 struct nilfs_btnode_chkey_ctxt bp_ctxt;
49 void (*bp_op)(struct nilfs_btree *, struct nilfs_btree_path *,
50 int, __u64 *, __u64 *);
54 * B-tree path operations
57 static struct kmem_cache *nilfs_btree_path_cache;
59 int __init nilfs_btree_path_cache_init(void)
61 nilfs_btree_path_cache =
62 kmem_cache_create("nilfs2_btree_path_cache",
63 sizeof(struct nilfs_btree_path) *
64 NILFS_BTREE_LEVEL_MAX, 0, 0, NULL);
65 return (nilfs_btree_path_cache != NULL) ? 0 : -ENOMEM;
68 void nilfs_btree_path_cache_destroy(void)
70 kmem_cache_destroy(nilfs_btree_path_cache);
73 static inline struct nilfs_btree_path *
74 nilfs_btree_alloc_path(const struct nilfs_btree *btree)
76 return (struct nilfs_btree_path *)
77 kmem_cache_alloc(nilfs_btree_path_cache, GFP_NOFS);
80 static inline void nilfs_btree_free_path(const struct nilfs_btree *btree,
81 struct nilfs_btree_path *path)
83 kmem_cache_free(nilfs_btree_path_cache, path);
86 static void nilfs_btree_init_path(const struct nilfs_btree *btree,
87 struct nilfs_btree_path *path)
91 for (level = NILFS_BTREE_LEVEL_DATA;
92 level < NILFS_BTREE_LEVEL_MAX;
94 path[level].bp_bh = NULL;
95 path[level].bp_sib_bh = NULL;
96 path[level].bp_index = 0;
97 path[level].bp_oldreq.bpr_ptr = NILFS_BMAP_INVALID_PTR;
98 path[level].bp_newreq.bpr_ptr = NILFS_BMAP_INVALID_PTR;
99 path[level].bp_op = NULL;
103 static void nilfs_btree_clear_path(const struct nilfs_btree *btree,
104 struct nilfs_btree_path *path)
108 for (level = NILFS_BTREE_LEVEL_DATA;
109 level < NILFS_BTREE_LEVEL_MAX;
111 if (path[level].bp_bh != NULL) {
112 brelse(path[level].bp_bh);
113 path[level].bp_bh = NULL;
115 /* sib_bh is released or deleted by prepare or commit
117 path[level].bp_sib_bh = NULL;
118 path[level].bp_index = 0;
119 path[level].bp_oldreq.bpr_ptr = NILFS_BMAP_INVALID_PTR;
120 path[level].bp_newreq.bpr_ptr = NILFS_BMAP_INVALID_PTR;
121 path[level].bp_op = NULL;
126 * B-tree node operations
128 static int nilfs_btree_get_block(const struct nilfs_btree *btree, __u64 ptr,
129 struct buffer_head **bhp)
131 struct address_space *btnc =
132 &NILFS_BMAP_I((struct nilfs_bmap *)btree)->i_btnode_cache;
133 return nilfs_btnode_get(btnc, ptr, 0, bhp, 0);
136 static int nilfs_btree_get_new_block(const struct nilfs_btree *btree,
137 __u64 ptr, struct buffer_head **bhp)
139 struct address_space *btnc =
140 &NILFS_BMAP_I((struct nilfs_bmap *)btree)->i_btnode_cache;
143 ret = nilfs_btnode_get(btnc, ptr, 0, bhp, 1);
145 set_buffer_nilfs_volatile(*bhp);
150 nilfs_btree_node_get_flags(const struct nilfs_btree *btree,
151 const struct nilfs_btree_node *node)
153 return node->bn_flags;
157 nilfs_btree_node_set_flags(struct nilfs_btree *btree,
158 struct nilfs_btree_node *node,
161 node->bn_flags = flags;
164 static inline int nilfs_btree_node_root(const struct nilfs_btree *btree,
165 const struct nilfs_btree_node *node)
167 return nilfs_btree_node_get_flags(btree, node) & NILFS_BTREE_NODE_ROOT;
171 nilfs_btree_node_get_level(const struct nilfs_btree *btree,
172 const struct nilfs_btree_node *node)
174 return node->bn_level;
178 nilfs_btree_node_set_level(struct nilfs_btree *btree,
179 struct nilfs_btree_node *node,
182 node->bn_level = level;
186 nilfs_btree_node_get_nchildren(const struct nilfs_btree *btree,
187 const struct nilfs_btree_node *node)
189 return le16_to_cpu(node->bn_nchildren);
193 nilfs_btree_node_set_nchildren(struct nilfs_btree *btree,
194 struct nilfs_btree_node *node,
197 node->bn_nchildren = cpu_to_le16(nchildren);
201 nilfs_btree_node_size(const struct nilfs_btree *btree)
203 return 1 << btree->bt_bmap.b_inode->i_blkbits;
207 nilfs_btree_node_nchildren_min(const struct nilfs_btree *btree,
208 const struct nilfs_btree_node *node)
210 return nilfs_btree_node_root(btree, node) ?
211 NILFS_BTREE_ROOT_NCHILDREN_MIN :
212 NILFS_BTREE_NODE_NCHILDREN_MIN(nilfs_btree_node_size(btree));
216 nilfs_btree_node_nchildren_max(const struct nilfs_btree *btree,
217 const struct nilfs_btree_node *node)
219 return nilfs_btree_node_root(btree, node) ?
220 NILFS_BTREE_ROOT_NCHILDREN_MAX :
221 NILFS_BTREE_NODE_NCHILDREN_MAX(nilfs_btree_node_size(btree));
224 static inline __le64 *
225 nilfs_btree_node_dkeys(const struct nilfs_btree *btree,
226 const struct nilfs_btree_node *node)
228 return (__le64 *)((char *)(node + 1) +
229 (nilfs_btree_node_root(btree, node) ?
230 0 : NILFS_BTREE_NODE_EXTRA_PAD_SIZE));
233 static inline __le64 *
234 nilfs_btree_node_dptrs(const struct nilfs_btree *btree,
235 const struct nilfs_btree_node *node)
237 return (__le64 *)(nilfs_btree_node_dkeys(btree, node) +
238 nilfs_btree_node_nchildren_max(btree, node));
242 nilfs_btree_node_get_key(const struct nilfs_btree *btree,
243 const struct nilfs_btree_node *node, int index)
245 return nilfs_bmap_dkey_to_key(*(nilfs_btree_node_dkeys(btree, node) +
250 nilfs_btree_node_set_key(struct nilfs_btree *btree,
251 struct nilfs_btree_node *node, int index, __u64 key)
253 *(nilfs_btree_node_dkeys(btree, node) + index) =
254 nilfs_bmap_key_to_dkey(key);
258 nilfs_btree_node_get_ptr(const struct nilfs_btree *btree,
259 const struct nilfs_btree_node *node,
262 return nilfs_bmap_dptr_to_ptr(*(nilfs_btree_node_dptrs(btree, node) +
267 nilfs_btree_node_set_ptr(struct nilfs_btree *btree,
268 struct nilfs_btree_node *node,
272 *(nilfs_btree_node_dptrs(btree, node) + index) =
273 nilfs_bmap_ptr_to_dptr(ptr);
276 static void nilfs_btree_node_init(struct nilfs_btree *btree,
277 struct nilfs_btree_node *node,
278 int flags, int level, int nchildren,
279 const __u64 *keys, const __u64 *ptrs)
285 nilfs_btree_node_set_flags(btree, node, flags);
286 nilfs_btree_node_set_level(btree, node, level);
287 nilfs_btree_node_set_nchildren(btree, node, nchildren);
289 dkeys = nilfs_btree_node_dkeys(btree, node);
290 dptrs = nilfs_btree_node_dptrs(btree, node);
291 for (i = 0; i < nchildren; i++) {
292 dkeys[i] = nilfs_bmap_key_to_dkey(keys[i]);
293 dptrs[i] = nilfs_bmap_ptr_to_dptr(ptrs[i]);
297 /* Assume the buffer heads corresponding to left and right are locked. */
298 static void nilfs_btree_node_move_left(struct nilfs_btree *btree,
299 struct nilfs_btree_node *left,
300 struct nilfs_btree_node *right,
303 __le64 *ldkeys, *rdkeys;
304 __le64 *ldptrs, *rdptrs;
305 int lnchildren, rnchildren;
307 ldkeys = nilfs_btree_node_dkeys(btree, left);
308 ldptrs = nilfs_btree_node_dptrs(btree, left);
309 lnchildren = nilfs_btree_node_get_nchildren(btree, left);
311 rdkeys = nilfs_btree_node_dkeys(btree, right);
312 rdptrs = nilfs_btree_node_dptrs(btree, right);
313 rnchildren = nilfs_btree_node_get_nchildren(btree, right);
315 memcpy(ldkeys + lnchildren, rdkeys, n * sizeof(*rdkeys));
316 memcpy(ldptrs + lnchildren, rdptrs, n * sizeof(*rdptrs));
317 memmove(rdkeys, rdkeys + n, (rnchildren - n) * sizeof(*rdkeys));
318 memmove(rdptrs, rdptrs + n, (rnchildren - n) * sizeof(*rdptrs));
322 nilfs_btree_node_set_nchildren(btree, left, lnchildren);
323 nilfs_btree_node_set_nchildren(btree, right, rnchildren);
326 /* Assume that the buffer heads corresponding to left and right are locked. */
327 static void nilfs_btree_node_move_right(struct nilfs_btree *btree,
328 struct nilfs_btree_node *left,
329 struct nilfs_btree_node *right,
332 __le64 *ldkeys, *rdkeys;
333 __le64 *ldptrs, *rdptrs;
334 int lnchildren, rnchildren;
336 ldkeys = nilfs_btree_node_dkeys(btree, left);
337 ldptrs = nilfs_btree_node_dptrs(btree, left);
338 lnchildren = nilfs_btree_node_get_nchildren(btree, left);
340 rdkeys = nilfs_btree_node_dkeys(btree, right);
341 rdptrs = nilfs_btree_node_dptrs(btree, right);
342 rnchildren = nilfs_btree_node_get_nchildren(btree, right);
344 memmove(rdkeys + n, rdkeys, rnchildren * sizeof(*rdkeys));
345 memmove(rdptrs + n, rdptrs, rnchildren * sizeof(*rdptrs));
346 memcpy(rdkeys, ldkeys + lnchildren - n, n * sizeof(*rdkeys));
347 memcpy(rdptrs, ldptrs + lnchildren - n, n * sizeof(*rdptrs));
351 nilfs_btree_node_set_nchildren(btree, left, lnchildren);
352 nilfs_btree_node_set_nchildren(btree, right, rnchildren);
355 /* Assume that the buffer head corresponding to node is locked. */
356 static void nilfs_btree_node_insert(struct nilfs_btree *btree,
357 struct nilfs_btree_node *node,
358 __u64 key, __u64 ptr, int index)
364 dkeys = nilfs_btree_node_dkeys(btree, node);
365 dptrs = nilfs_btree_node_dptrs(btree, node);
366 nchildren = nilfs_btree_node_get_nchildren(btree, node);
367 if (index < nchildren) {
368 memmove(dkeys + index + 1, dkeys + index,
369 (nchildren - index) * sizeof(*dkeys));
370 memmove(dptrs + index + 1, dptrs + index,
371 (nchildren - index) * sizeof(*dptrs));
373 dkeys[index] = nilfs_bmap_key_to_dkey(key);
374 dptrs[index] = nilfs_bmap_ptr_to_dptr(ptr);
376 nilfs_btree_node_set_nchildren(btree, node, nchildren);
379 /* Assume that the buffer head corresponding to node is locked. */
380 static void nilfs_btree_node_delete(struct nilfs_btree *btree,
381 struct nilfs_btree_node *node,
382 __u64 *keyp, __u64 *ptrp, int index)
390 dkeys = nilfs_btree_node_dkeys(btree, node);
391 dptrs = nilfs_btree_node_dptrs(btree, node);
392 key = nilfs_bmap_dkey_to_key(dkeys[index]);
393 ptr = nilfs_bmap_dptr_to_ptr(dptrs[index]);
394 nchildren = nilfs_btree_node_get_nchildren(btree, node);
400 if (index < nchildren - 1) {
401 memmove(dkeys + index, dkeys + index + 1,
402 (nchildren - index - 1) * sizeof(*dkeys));
403 memmove(dptrs + index, dptrs + index + 1,
404 (nchildren - index - 1) * sizeof(*dptrs));
407 nilfs_btree_node_set_nchildren(btree, node, nchildren);
410 static int nilfs_btree_node_lookup(const struct nilfs_btree *btree,
411 const struct nilfs_btree_node *node,
412 __u64 key, int *indexp)
415 int index, low, high, s;
419 high = nilfs_btree_node_get_nchildren(btree, node) - 1;
422 while (low <= high) {
423 index = (low + high) / 2;
424 nkey = nilfs_btree_node_get_key(btree, node, index);
428 } else if (nkey < key) {
438 if (nilfs_btree_node_get_level(btree, node) >
439 NILFS_BTREE_LEVEL_NODE_MIN) {
440 if ((s > 0) && (index > 0))
451 static inline struct nilfs_btree_node *
452 nilfs_btree_get_root(const struct nilfs_btree *btree)
454 return (struct nilfs_btree_node *)btree->bt_bmap.b_u.u_data;
457 static inline struct nilfs_btree_node *
458 nilfs_btree_get_nonroot_node(const struct nilfs_btree *btree,
459 const struct nilfs_btree_path *path,
462 return (struct nilfs_btree_node *)path[level].bp_bh->b_data;
465 static inline struct nilfs_btree_node *
466 nilfs_btree_get_sib_node(const struct nilfs_btree *btree,
467 const struct nilfs_btree_path *path,
470 return (struct nilfs_btree_node *)path[level].bp_sib_bh->b_data;
473 static inline int nilfs_btree_height(const struct nilfs_btree *btree)
475 return nilfs_btree_node_get_level(btree, nilfs_btree_get_root(btree))
479 static inline struct nilfs_btree_node *
480 nilfs_btree_get_node(const struct nilfs_btree *btree,
481 const struct nilfs_btree_path *path,
484 return (level == nilfs_btree_height(btree) - 1) ?
485 nilfs_btree_get_root(btree) :
486 nilfs_btree_get_nonroot_node(btree, path, level);
489 static int nilfs_btree_do_lookup(const struct nilfs_btree *btree,
490 struct nilfs_btree_path *path,
491 __u64 key, __u64 *ptrp, int minlevel)
493 struct nilfs_btree_node *node;
495 int level, index, found, ret;
497 node = nilfs_btree_get_root(btree);
498 level = nilfs_btree_node_get_level(btree, node);
499 if ((level < minlevel) ||
500 (nilfs_btree_node_get_nchildren(btree, node) <= 0))
503 found = nilfs_btree_node_lookup(btree, node, key, &index);
504 ptr = nilfs_btree_node_get_ptr(btree, node, index);
505 path[level].bp_bh = NULL;
506 path[level].bp_index = index;
508 for (level--; level >= minlevel; level--) {
509 ret = nilfs_btree_get_block(btree, ptr, &path[level].bp_bh);
512 node = nilfs_btree_get_nonroot_node(btree, path, level);
513 BUG_ON(level != nilfs_btree_node_get_level(btree, node));
515 found = nilfs_btree_node_lookup(btree, node, key,
519 if (index < nilfs_btree_node_nchildren_max(btree, node))
520 ptr = nilfs_btree_node_get_ptr(btree, node, index);
522 WARN_ON(found || level != NILFS_BTREE_LEVEL_NODE_MIN);
524 ptr = NILFS_BMAP_INVALID_PTR;
526 path[level].bp_index = index;
537 static int nilfs_btree_do_lookup_last(const struct nilfs_btree *btree,
538 struct nilfs_btree_path *path,
539 __u64 *keyp, __u64 *ptrp)
541 struct nilfs_btree_node *node;
543 int index, level, ret;
545 node = nilfs_btree_get_root(btree);
546 index = nilfs_btree_node_get_nchildren(btree, node) - 1;
549 level = nilfs_btree_node_get_level(btree, node);
550 ptr = nilfs_btree_node_get_ptr(btree, node, index);
551 path[level].bp_bh = NULL;
552 path[level].bp_index = index;
554 for (level--; level > 0; level--) {
555 ret = nilfs_btree_get_block(btree, ptr, &path[level].bp_bh);
558 node = nilfs_btree_get_nonroot_node(btree, path, level);
559 BUG_ON(level != nilfs_btree_node_get_level(btree, node));
560 index = nilfs_btree_node_get_nchildren(btree, node) - 1;
561 ptr = nilfs_btree_node_get_ptr(btree, node, index);
562 path[level].bp_index = index;
566 *keyp = nilfs_btree_node_get_key(btree, node, index);
573 static int nilfs_btree_lookup(const struct nilfs_bmap *bmap,
574 __u64 key, int level, __u64 *ptrp)
576 struct nilfs_btree *btree;
577 struct nilfs_btree_path *path;
581 btree = (struct nilfs_btree *)bmap;
582 path = nilfs_btree_alloc_path(btree);
585 nilfs_btree_init_path(btree, path);
587 ret = nilfs_btree_do_lookup(btree, path, key, &ptr, level);
592 nilfs_btree_clear_path(btree, path);
593 nilfs_btree_free_path(btree, path);
598 static void nilfs_btree_promote_key(struct nilfs_btree *btree,
599 struct nilfs_btree_path *path,
600 int level, __u64 key)
602 if (level < nilfs_btree_height(btree) - 1) {
604 lock_buffer(path[level].bp_bh);
605 nilfs_btree_node_set_key(
607 nilfs_btree_get_nonroot_node(
609 path[level].bp_index, key);
610 if (!buffer_dirty(path[level].bp_bh))
611 nilfs_btnode_mark_dirty(path[level].bp_bh);
612 unlock_buffer(path[level].bp_bh);
613 } while ((path[level].bp_index == 0) &&
614 (++level < nilfs_btree_height(btree) - 1));
618 if (level == nilfs_btree_height(btree) - 1) {
619 nilfs_btree_node_set_key(btree,
620 nilfs_btree_get_root(btree),
621 path[level].bp_index, key);
625 static void nilfs_btree_do_insert(struct nilfs_btree *btree,
626 struct nilfs_btree_path *path,
627 int level, __u64 *keyp, __u64 *ptrp)
629 struct nilfs_btree_node *node;
631 if (level < nilfs_btree_height(btree) - 1) {
632 lock_buffer(path[level].bp_bh);
633 node = nilfs_btree_get_nonroot_node(btree, path, level);
634 nilfs_btree_node_insert(btree, node, *keyp, *ptrp,
635 path[level].bp_index);
636 if (!buffer_dirty(path[level].bp_bh))
637 nilfs_btnode_mark_dirty(path[level].bp_bh);
638 unlock_buffer(path[level].bp_bh);
640 if (path[level].bp_index == 0)
641 nilfs_btree_promote_key(btree, path, level + 1,
642 nilfs_btree_node_get_key(
645 node = nilfs_btree_get_root(btree);
646 nilfs_btree_node_insert(btree, node, *keyp, *ptrp,
647 path[level].bp_index);
651 static void nilfs_btree_carry_left(struct nilfs_btree *btree,
652 struct nilfs_btree_path *path,
653 int level, __u64 *keyp, __u64 *ptrp)
655 struct nilfs_btree_node *node, *left;
656 int nchildren, lnchildren, n, move;
658 lock_buffer(path[level].bp_bh);
659 lock_buffer(path[level].bp_sib_bh);
661 node = nilfs_btree_get_nonroot_node(btree, path, level);
662 left = nilfs_btree_get_sib_node(btree, path, level);
663 nchildren = nilfs_btree_node_get_nchildren(btree, node);
664 lnchildren = nilfs_btree_node_get_nchildren(btree, left);
667 n = (nchildren + lnchildren + 1) / 2 - lnchildren;
668 if (n > path[level].bp_index) {
669 /* move insert point */
674 nilfs_btree_node_move_left(btree, left, node, n);
676 if (!buffer_dirty(path[level].bp_bh))
677 nilfs_btnode_mark_dirty(path[level].bp_bh);
678 if (!buffer_dirty(path[level].bp_sib_bh))
679 nilfs_btnode_mark_dirty(path[level].bp_sib_bh);
681 unlock_buffer(path[level].bp_bh);
682 unlock_buffer(path[level].bp_sib_bh);
684 nilfs_btree_promote_key(btree, path, level + 1,
685 nilfs_btree_node_get_key(btree, node, 0));
688 brelse(path[level].bp_bh);
689 path[level].bp_bh = path[level].bp_sib_bh;
690 path[level].bp_sib_bh = NULL;
691 path[level].bp_index += lnchildren;
692 path[level + 1].bp_index--;
694 brelse(path[level].bp_sib_bh);
695 path[level].bp_sib_bh = NULL;
696 path[level].bp_index -= n;
699 nilfs_btree_do_insert(btree, path, level, keyp, ptrp);
702 static void nilfs_btree_carry_right(struct nilfs_btree *btree,
703 struct nilfs_btree_path *path,
704 int level, __u64 *keyp, __u64 *ptrp)
706 struct nilfs_btree_node *node, *right;
707 int nchildren, rnchildren, n, move;
709 lock_buffer(path[level].bp_bh);
710 lock_buffer(path[level].bp_sib_bh);
712 node = nilfs_btree_get_nonroot_node(btree, path, level);
713 right = nilfs_btree_get_sib_node(btree, path, level);
714 nchildren = nilfs_btree_node_get_nchildren(btree, node);
715 rnchildren = nilfs_btree_node_get_nchildren(btree, right);
718 n = (nchildren + rnchildren + 1) / 2 - rnchildren;
719 if (n > nchildren - path[level].bp_index) {
720 /* move insert point */
725 nilfs_btree_node_move_right(btree, node, right, n);
727 if (!buffer_dirty(path[level].bp_bh))
728 nilfs_btnode_mark_dirty(path[level].bp_bh);
729 if (!buffer_dirty(path[level].bp_sib_bh))
730 nilfs_btnode_mark_dirty(path[level].bp_sib_bh);
732 unlock_buffer(path[level].bp_bh);
733 unlock_buffer(path[level].bp_sib_bh);
735 path[level + 1].bp_index++;
736 nilfs_btree_promote_key(btree, path, level + 1,
737 nilfs_btree_node_get_key(btree, right, 0));
738 path[level + 1].bp_index--;
741 brelse(path[level].bp_bh);
742 path[level].bp_bh = path[level].bp_sib_bh;
743 path[level].bp_sib_bh = NULL;
744 path[level].bp_index -=
745 nilfs_btree_node_get_nchildren(btree, node);
746 path[level + 1].bp_index++;
748 brelse(path[level].bp_sib_bh);
749 path[level].bp_sib_bh = NULL;
752 nilfs_btree_do_insert(btree, path, level, keyp, ptrp);
755 static void nilfs_btree_split(struct nilfs_btree *btree,
756 struct nilfs_btree_path *path,
757 int level, __u64 *keyp, __u64 *ptrp)
759 struct nilfs_btree_node *node, *right;
762 int nchildren, n, move;
764 lock_buffer(path[level].bp_bh);
765 lock_buffer(path[level].bp_sib_bh);
767 node = nilfs_btree_get_nonroot_node(btree, path, level);
768 right = nilfs_btree_get_sib_node(btree, path, level);
769 nchildren = nilfs_btree_node_get_nchildren(btree, node);
772 n = (nchildren + 1) / 2;
773 if (n > nchildren - path[level].bp_index) {
778 nilfs_btree_node_move_right(btree, node, right, n);
780 if (!buffer_dirty(path[level].bp_bh))
781 nilfs_btnode_mark_dirty(path[level].bp_bh);
782 if (!buffer_dirty(path[level].bp_sib_bh))
783 nilfs_btnode_mark_dirty(path[level].bp_sib_bh);
785 unlock_buffer(path[level].bp_bh);
786 unlock_buffer(path[level].bp_sib_bh);
788 newkey = nilfs_btree_node_get_key(btree, right, 0);
789 newptr = path[level].bp_newreq.bpr_ptr;
792 path[level].bp_index -=
793 nilfs_btree_node_get_nchildren(btree, node);
794 nilfs_btree_node_insert(btree, right, *keyp, *ptrp,
795 path[level].bp_index);
797 *keyp = nilfs_btree_node_get_key(btree, right, 0);
798 *ptrp = path[level].bp_newreq.bpr_ptr;
800 brelse(path[level].bp_bh);
801 path[level].bp_bh = path[level].bp_sib_bh;
802 path[level].bp_sib_bh = NULL;
804 nilfs_btree_do_insert(btree, path, level, keyp, ptrp);
806 *keyp = nilfs_btree_node_get_key(btree, right, 0);
807 *ptrp = path[level].bp_newreq.bpr_ptr;
809 brelse(path[level].bp_sib_bh);
810 path[level].bp_sib_bh = NULL;
813 path[level + 1].bp_index++;
816 static void nilfs_btree_grow(struct nilfs_btree *btree,
817 struct nilfs_btree_path *path,
818 int level, __u64 *keyp, __u64 *ptrp)
820 struct nilfs_btree_node *root, *child;
823 lock_buffer(path[level].bp_sib_bh);
825 root = nilfs_btree_get_root(btree);
826 child = nilfs_btree_get_sib_node(btree, path, level);
828 n = nilfs_btree_node_get_nchildren(btree, root);
830 nilfs_btree_node_move_right(btree, root, child, n);
831 nilfs_btree_node_set_level(btree, root, level + 1);
833 if (!buffer_dirty(path[level].bp_sib_bh))
834 nilfs_btnode_mark_dirty(path[level].bp_sib_bh);
836 unlock_buffer(path[level].bp_sib_bh);
838 path[level].bp_bh = path[level].bp_sib_bh;
839 path[level].bp_sib_bh = NULL;
841 nilfs_btree_do_insert(btree, path, level, keyp, ptrp);
843 *keyp = nilfs_btree_node_get_key(btree, child, 0);
844 *ptrp = path[level].bp_newreq.bpr_ptr;
847 static __u64 nilfs_btree_find_near(const struct nilfs_btree *btree,
848 const struct nilfs_btree_path *path)
850 struct nilfs_btree_node *node;
854 return NILFS_BMAP_INVALID_PTR;
857 level = NILFS_BTREE_LEVEL_NODE_MIN;
858 if (path[level].bp_index > 0) {
859 node = nilfs_btree_get_node(btree, path, level);
860 return nilfs_btree_node_get_ptr(btree, node,
861 path[level].bp_index - 1);
865 level = NILFS_BTREE_LEVEL_NODE_MIN + 1;
866 if (level <= nilfs_btree_height(btree) - 1) {
867 node = nilfs_btree_get_node(btree, path, level);
868 return nilfs_btree_node_get_ptr(btree, node,
869 path[level].bp_index);
872 return NILFS_BMAP_INVALID_PTR;
875 static __u64 nilfs_btree_find_target_v(const struct nilfs_btree *btree,
876 const struct nilfs_btree_path *path,
881 ptr = nilfs_bmap_find_target_seq(&btree->bt_bmap, key);
882 if (ptr != NILFS_BMAP_INVALID_PTR)
883 /* sequential access */
886 ptr = nilfs_btree_find_near(btree, path);
887 if (ptr != NILFS_BMAP_INVALID_PTR)
892 return nilfs_bmap_find_target_in_group(&btree->bt_bmap);
895 static void nilfs_btree_set_target_v(struct nilfs_btree *btree, __u64 key,
898 btree->bt_bmap.b_last_allocated_key = key;
899 btree->bt_bmap.b_last_allocated_ptr = ptr;
902 static int nilfs_btree_prepare_insert(struct nilfs_btree *btree,
903 struct nilfs_btree_path *path,
904 int *levelp, __u64 key, __u64 ptr,
905 struct nilfs_bmap_stats *stats)
907 struct buffer_head *bh;
908 struct nilfs_btree_node *node, *parent, *sib;
910 int pindex, level, ret;
912 stats->bs_nblocks = 0;
913 level = NILFS_BTREE_LEVEL_DATA;
915 /* allocate a new ptr for data block */
916 if (btree->bt_ops->btop_find_target != NULL)
917 path[level].bp_newreq.bpr_ptr =
918 btree->bt_ops->btop_find_target(btree, path, key);
920 ret = btree->bt_bmap.b_pops->bpop_prepare_alloc_ptr(
921 &btree->bt_bmap, &path[level].bp_newreq);
925 for (level = NILFS_BTREE_LEVEL_NODE_MIN;
926 level < nilfs_btree_height(btree) - 1;
928 node = nilfs_btree_get_nonroot_node(btree, path, level);
929 if (nilfs_btree_node_get_nchildren(btree, node) <
930 nilfs_btree_node_nchildren_max(btree, node)) {
931 path[level].bp_op = nilfs_btree_do_insert;
936 parent = nilfs_btree_get_node(btree, path, level + 1);
937 pindex = path[level + 1].bp_index;
941 sibptr = nilfs_btree_node_get_ptr(btree, parent,
943 ret = nilfs_btree_get_block(btree, sibptr, &bh);
945 goto err_out_child_node;
946 sib = (struct nilfs_btree_node *)bh->b_data;
947 if (nilfs_btree_node_get_nchildren(btree, sib) <
948 nilfs_btree_node_nchildren_max(btree, sib)) {
949 path[level].bp_sib_bh = bh;
950 path[level].bp_op = nilfs_btree_carry_left;
959 nilfs_btree_node_get_nchildren(btree, parent) - 1) {
960 sibptr = nilfs_btree_node_get_ptr(btree, parent,
962 ret = nilfs_btree_get_block(btree, sibptr, &bh);
964 goto err_out_child_node;
965 sib = (struct nilfs_btree_node *)bh->b_data;
966 if (nilfs_btree_node_get_nchildren(btree, sib) <
967 nilfs_btree_node_nchildren_max(btree, sib)) {
968 path[level].bp_sib_bh = bh;
969 path[level].bp_op = nilfs_btree_carry_right;
977 path[level].bp_newreq.bpr_ptr =
978 path[level - 1].bp_newreq.bpr_ptr + 1;
979 ret = btree->bt_bmap.b_pops->bpop_prepare_alloc_ptr(
980 &btree->bt_bmap, &path[level].bp_newreq);
982 goto err_out_child_node;
983 ret = nilfs_btree_get_new_block(btree,
984 path[level].bp_newreq.bpr_ptr,
987 goto err_out_curr_node;
992 nilfs_btree_node_init(btree,
993 (struct nilfs_btree_node *)bh->b_data,
994 0, level, 0, NULL, NULL);
996 path[level].bp_sib_bh = bh;
997 path[level].bp_op = nilfs_btree_split;
1001 node = nilfs_btree_get_root(btree);
1002 if (nilfs_btree_node_get_nchildren(btree, node) <
1003 nilfs_btree_node_nchildren_max(btree, node)) {
1004 path[level].bp_op = nilfs_btree_do_insert;
1005 stats->bs_nblocks++;
1010 path[level].bp_newreq.bpr_ptr = path[level - 1].bp_newreq.bpr_ptr + 1;
1011 ret = btree->bt_bmap.b_pops->bpop_prepare_alloc_ptr(
1012 &btree->bt_bmap, &path[level].bp_newreq);
1014 goto err_out_child_node;
1015 ret = nilfs_btree_get_new_block(btree, path[level].bp_newreq.bpr_ptr,
1018 goto err_out_curr_node;
1021 nilfs_btree_node_init(btree, (struct nilfs_btree_node *)bh->b_data,
1022 0, level, 0, NULL, NULL);
1024 path[level].bp_sib_bh = bh;
1025 path[level].bp_op = nilfs_btree_grow;
1028 path[level].bp_op = nilfs_btree_do_insert;
1030 /* a newly-created node block and a data block are added */
1031 stats->bs_nblocks += 2;
1040 btree->bt_bmap.b_pops->bpop_abort_alloc_ptr(&btree->bt_bmap,
1041 &path[level].bp_newreq);
1043 for (level--; level > NILFS_BTREE_LEVEL_DATA; level--) {
1044 nilfs_btnode_delete(path[level].bp_sib_bh);
1045 btree->bt_bmap.b_pops->bpop_abort_alloc_ptr(
1046 &btree->bt_bmap, &path[level].bp_newreq);
1050 btree->bt_bmap.b_pops->bpop_abort_alloc_ptr(&btree->bt_bmap,
1051 &path[level].bp_newreq);
1054 stats->bs_nblocks = 0;
1058 static void nilfs_btree_commit_insert(struct nilfs_btree *btree,
1059 struct nilfs_btree_path *path,
1060 int maxlevel, __u64 key, __u64 ptr)
1064 set_buffer_nilfs_volatile((struct buffer_head *)((unsigned long)ptr));
1065 ptr = path[NILFS_BTREE_LEVEL_DATA].bp_newreq.bpr_ptr;
1066 if (btree->bt_ops->btop_set_target != NULL)
1067 btree->bt_ops->btop_set_target(btree, key, ptr);
1069 for (level = NILFS_BTREE_LEVEL_NODE_MIN; level <= maxlevel; level++) {
1070 if (btree->bt_bmap.b_pops->bpop_commit_alloc_ptr != NULL) {
1071 btree->bt_bmap.b_pops->bpop_commit_alloc_ptr(
1072 &btree->bt_bmap, &path[level - 1].bp_newreq);
1074 path[level].bp_op(btree, path, level, &key, &ptr);
1077 if (!nilfs_bmap_dirty(&btree->bt_bmap))
1078 nilfs_bmap_set_dirty(&btree->bt_bmap);
1081 static int nilfs_btree_insert(struct nilfs_bmap *bmap, __u64 key, __u64 ptr)
1083 struct nilfs_btree *btree;
1084 struct nilfs_btree_path *path;
1085 struct nilfs_bmap_stats stats;
1088 btree = (struct nilfs_btree *)bmap;
1089 path = nilfs_btree_alloc_path(btree);
1092 nilfs_btree_init_path(btree, path);
1094 ret = nilfs_btree_do_lookup(btree, path, key, NULL,
1095 NILFS_BTREE_LEVEL_NODE_MIN);
1096 if (ret != -ENOENT) {
1102 ret = nilfs_btree_prepare_insert(btree, path, &level, key, ptr, &stats);
1105 nilfs_btree_commit_insert(btree, path, level, key, ptr);
1106 nilfs_bmap_add_blocks(bmap, stats.bs_nblocks);
1109 nilfs_btree_clear_path(btree, path);
1110 nilfs_btree_free_path(btree, path);
1114 static void nilfs_btree_do_delete(struct nilfs_btree *btree,
1115 struct nilfs_btree_path *path,
1116 int level, __u64 *keyp, __u64 *ptrp)
1118 struct nilfs_btree_node *node;
1120 if (level < nilfs_btree_height(btree) - 1) {
1121 lock_buffer(path[level].bp_bh);
1122 node = nilfs_btree_get_nonroot_node(btree, path, level);
1123 nilfs_btree_node_delete(btree, node, keyp, ptrp,
1124 path[level].bp_index);
1125 if (!buffer_dirty(path[level].bp_bh))
1126 nilfs_btnode_mark_dirty(path[level].bp_bh);
1127 unlock_buffer(path[level].bp_bh);
1128 if (path[level].bp_index == 0)
1129 nilfs_btree_promote_key(btree, path, level + 1,
1130 nilfs_btree_node_get_key(btree, node, 0));
1132 node = nilfs_btree_get_root(btree);
1133 nilfs_btree_node_delete(btree, node, keyp, ptrp,
1134 path[level].bp_index);
1138 static void nilfs_btree_borrow_left(struct nilfs_btree *btree,
1139 struct nilfs_btree_path *path,
1140 int level, __u64 *keyp, __u64 *ptrp)
1142 struct nilfs_btree_node *node, *left;
1143 int nchildren, lnchildren, n;
1145 nilfs_btree_do_delete(btree, path, level, keyp, ptrp);
1147 lock_buffer(path[level].bp_bh);
1148 lock_buffer(path[level].bp_sib_bh);
1150 node = nilfs_btree_get_nonroot_node(btree, path, level);
1151 left = nilfs_btree_get_sib_node(btree, path, level);
1152 nchildren = nilfs_btree_node_get_nchildren(btree, node);
1153 lnchildren = nilfs_btree_node_get_nchildren(btree, left);
1155 n = (nchildren + lnchildren) / 2 - nchildren;
1157 nilfs_btree_node_move_right(btree, left, node, n);
1159 if (!buffer_dirty(path[level].bp_bh))
1160 nilfs_btnode_mark_dirty(path[level].bp_bh);
1161 if (!buffer_dirty(path[level].bp_sib_bh))
1162 nilfs_btnode_mark_dirty(path[level].bp_sib_bh);
1164 unlock_buffer(path[level].bp_bh);
1165 unlock_buffer(path[level].bp_sib_bh);
1167 nilfs_btree_promote_key(btree, path, level + 1,
1168 nilfs_btree_node_get_key(btree, node, 0));
1170 brelse(path[level].bp_sib_bh);
1171 path[level].bp_sib_bh = NULL;
1172 path[level].bp_index += n;
1175 static void nilfs_btree_borrow_right(struct nilfs_btree *btree,
1176 struct nilfs_btree_path *path,
1177 int level, __u64 *keyp, __u64 *ptrp)
1179 struct nilfs_btree_node *node, *right;
1180 int nchildren, rnchildren, n;
1182 nilfs_btree_do_delete(btree, path, level, keyp, ptrp);
1184 lock_buffer(path[level].bp_bh);
1185 lock_buffer(path[level].bp_sib_bh);
1187 node = nilfs_btree_get_nonroot_node(btree, path, level);
1188 right = nilfs_btree_get_sib_node(btree, path, level);
1189 nchildren = nilfs_btree_node_get_nchildren(btree, node);
1190 rnchildren = nilfs_btree_node_get_nchildren(btree, right);
1192 n = (nchildren + rnchildren) / 2 - nchildren;
1194 nilfs_btree_node_move_left(btree, node, right, n);
1196 if (!buffer_dirty(path[level].bp_bh))
1197 nilfs_btnode_mark_dirty(path[level].bp_bh);
1198 if (!buffer_dirty(path[level].bp_sib_bh))
1199 nilfs_btnode_mark_dirty(path[level].bp_sib_bh);
1201 unlock_buffer(path[level].bp_bh);
1202 unlock_buffer(path[level].bp_sib_bh);
1204 path[level + 1].bp_index++;
1205 nilfs_btree_promote_key(btree, path, level + 1,
1206 nilfs_btree_node_get_key(btree, right, 0));
1207 path[level + 1].bp_index--;
1209 brelse(path[level].bp_sib_bh);
1210 path[level].bp_sib_bh = NULL;
1213 static void nilfs_btree_concat_left(struct nilfs_btree *btree,
1214 struct nilfs_btree_path *path,
1215 int level, __u64 *keyp, __u64 *ptrp)
1217 struct nilfs_btree_node *node, *left;
1220 nilfs_btree_do_delete(btree, path, level, keyp, ptrp);
1222 lock_buffer(path[level].bp_bh);
1223 lock_buffer(path[level].bp_sib_bh);
1225 node = nilfs_btree_get_nonroot_node(btree, path, level);
1226 left = nilfs_btree_get_sib_node(btree, path, level);
1228 n = nilfs_btree_node_get_nchildren(btree, node);
1230 nilfs_btree_node_move_left(btree, left, node, n);
1232 if (!buffer_dirty(path[level].bp_sib_bh))
1233 nilfs_btnode_mark_dirty(path[level].bp_sib_bh);
1235 unlock_buffer(path[level].bp_bh);
1236 unlock_buffer(path[level].bp_sib_bh);
1238 nilfs_btnode_delete(path[level].bp_bh);
1239 path[level].bp_bh = path[level].bp_sib_bh;
1240 path[level].bp_sib_bh = NULL;
1241 path[level].bp_index += nilfs_btree_node_get_nchildren(btree, left);
1244 static void nilfs_btree_concat_right(struct nilfs_btree *btree,
1245 struct nilfs_btree_path *path,
1246 int level, __u64 *keyp, __u64 *ptrp)
1248 struct nilfs_btree_node *node, *right;
1251 nilfs_btree_do_delete(btree, path, level, keyp, ptrp);
1253 lock_buffer(path[level].bp_bh);
1254 lock_buffer(path[level].bp_sib_bh);
1256 node = nilfs_btree_get_nonroot_node(btree, path, level);
1257 right = nilfs_btree_get_sib_node(btree, path, level);
1259 n = nilfs_btree_node_get_nchildren(btree, right);
1261 nilfs_btree_node_move_left(btree, node, right, n);
1263 if (!buffer_dirty(path[level].bp_bh))
1264 nilfs_btnode_mark_dirty(path[level].bp_bh);
1266 unlock_buffer(path[level].bp_bh);
1267 unlock_buffer(path[level].bp_sib_bh);
1269 nilfs_btnode_delete(path[level].bp_sib_bh);
1270 path[level].bp_sib_bh = NULL;
1271 path[level + 1].bp_index++;
1274 static void nilfs_btree_shrink(struct nilfs_btree *btree,
1275 struct nilfs_btree_path *path,
1276 int level, __u64 *keyp, __u64 *ptrp)
1278 struct nilfs_btree_node *root, *child;
1281 nilfs_btree_do_delete(btree, path, level, keyp, ptrp);
1283 lock_buffer(path[level].bp_bh);
1284 root = nilfs_btree_get_root(btree);
1285 child = nilfs_btree_get_nonroot_node(btree, path, level);
1287 nilfs_btree_node_delete(btree, root, NULL, NULL, 0);
1288 nilfs_btree_node_set_level(btree, root, level);
1289 n = nilfs_btree_node_get_nchildren(btree, child);
1290 nilfs_btree_node_move_left(btree, root, child, n);
1291 unlock_buffer(path[level].bp_bh);
1293 nilfs_btnode_delete(path[level].bp_bh);
1294 path[level].bp_bh = NULL;
1298 static int nilfs_btree_prepare_delete(struct nilfs_btree *btree,
1299 struct nilfs_btree_path *path,
1301 struct nilfs_bmap_stats *stats)
1303 struct buffer_head *bh;
1304 struct nilfs_btree_node *node, *parent, *sib;
1306 int pindex, level, ret;
1309 stats->bs_nblocks = 0;
1310 for (level = NILFS_BTREE_LEVEL_NODE_MIN;
1311 level < nilfs_btree_height(btree) - 1;
1313 node = nilfs_btree_get_nonroot_node(btree, path, level);
1314 path[level].bp_oldreq.bpr_ptr =
1315 nilfs_btree_node_get_ptr(btree, node,
1316 path[level].bp_index);
1317 if (btree->bt_bmap.b_pops->bpop_prepare_end_ptr != NULL) {
1318 ret = btree->bt_bmap.b_pops->bpop_prepare_end_ptr(
1319 &btree->bt_bmap, &path[level].bp_oldreq);
1321 goto err_out_child_node;
1324 if (nilfs_btree_node_get_nchildren(btree, node) >
1325 nilfs_btree_node_nchildren_min(btree, node)) {
1326 path[level].bp_op = nilfs_btree_do_delete;
1327 stats->bs_nblocks++;
1331 parent = nilfs_btree_get_node(btree, path, level + 1);
1332 pindex = path[level + 1].bp_index;
1336 sibptr = nilfs_btree_node_get_ptr(btree, parent,
1338 ret = nilfs_btree_get_block(btree, sibptr, &bh);
1340 goto err_out_curr_node;
1341 sib = (struct nilfs_btree_node *)bh->b_data;
1342 if (nilfs_btree_node_get_nchildren(btree, sib) >
1343 nilfs_btree_node_nchildren_min(btree, sib)) {
1344 path[level].bp_sib_bh = bh;
1345 path[level].bp_op = nilfs_btree_borrow_left;
1346 stats->bs_nblocks++;
1349 path[level].bp_sib_bh = bh;
1350 path[level].bp_op = nilfs_btree_concat_left;
1351 stats->bs_nblocks++;
1355 nilfs_btree_node_get_nchildren(btree, parent) - 1) {
1357 sibptr = nilfs_btree_node_get_ptr(btree, parent,
1359 ret = nilfs_btree_get_block(btree, sibptr, &bh);
1361 goto err_out_curr_node;
1362 sib = (struct nilfs_btree_node *)bh->b_data;
1363 if (nilfs_btree_node_get_nchildren(btree, sib) >
1364 nilfs_btree_node_nchildren_min(btree, sib)) {
1365 path[level].bp_sib_bh = bh;
1366 path[level].bp_op = nilfs_btree_borrow_right;
1367 stats->bs_nblocks++;
1370 path[level].bp_sib_bh = bh;
1371 path[level].bp_op = nilfs_btree_concat_right;
1372 stats->bs_nblocks++;
1377 /* the only child of the root node */
1378 WARN_ON(level != nilfs_btree_height(btree) - 2);
1379 if (nilfs_btree_node_get_nchildren(btree, node) - 1 <=
1380 NILFS_BTREE_ROOT_NCHILDREN_MAX) {
1381 path[level].bp_op = nilfs_btree_shrink;
1382 stats->bs_nblocks += 2;
1384 path[level].bp_op = nilfs_btree_do_delete;
1385 stats->bs_nblocks++;
1393 node = nilfs_btree_get_root(btree);
1394 path[level].bp_oldreq.bpr_ptr =
1395 nilfs_btree_node_get_ptr(btree, node, path[level].bp_index);
1396 if (btree->bt_bmap.b_pops->bpop_prepare_end_ptr != NULL) {
1397 ret = btree->bt_bmap.b_pops->bpop_prepare_end_ptr(
1398 &btree->bt_bmap, &path[level].bp_oldreq);
1400 goto err_out_child_node;
1402 /* child of the root node is deleted */
1403 path[level].bp_op = nilfs_btree_do_delete;
1404 stats->bs_nblocks++;
1413 if (btree->bt_bmap.b_pops->bpop_abort_end_ptr != NULL)
1414 btree->bt_bmap.b_pops->bpop_abort_end_ptr(
1415 &btree->bt_bmap, &path[level].bp_oldreq);
1417 for (level--; level >= NILFS_BTREE_LEVEL_NODE_MIN; level--) {
1418 brelse(path[level].bp_sib_bh);
1419 if (btree->bt_bmap.b_pops->bpop_abort_end_ptr != NULL)
1420 btree->bt_bmap.b_pops->bpop_abort_end_ptr(
1421 &btree->bt_bmap, &path[level].bp_oldreq);
1424 stats->bs_nblocks = 0;
1428 static void nilfs_btree_commit_delete(struct nilfs_btree *btree,
1429 struct nilfs_btree_path *path,
1434 for (level = NILFS_BTREE_LEVEL_NODE_MIN; level <= maxlevel; level++) {
1435 if (btree->bt_bmap.b_pops->bpop_commit_end_ptr != NULL)
1436 btree->bt_bmap.b_pops->bpop_commit_end_ptr(
1437 &btree->bt_bmap, &path[level].bp_oldreq);
1438 path[level].bp_op(btree, path, level, NULL, NULL);
1441 if (!nilfs_bmap_dirty(&btree->bt_bmap))
1442 nilfs_bmap_set_dirty(&btree->bt_bmap);
1445 static int nilfs_btree_delete(struct nilfs_bmap *bmap, __u64 key)
1448 struct nilfs_btree *btree;
1449 struct nilfs_btree_path *path;
1450 struct nilfs_bmap_stats stats;
1453 btree = (struct nilfs_btree *)bmap;
1454 path = nilfs_btree_alloc_path(btree);
1457 nilfs_btree_init_path(btree, path);
1458 ret = nilfs_btree_do_lookup(btree, path, key, NULL,
1459 NILFS_BTREE_LEVEL_NODE_MIN);
1463 ret = nilfs_btree_prepare_delete(btree, path, &level, &stats);
1466 nilfs_btree_commit_delete(btree, path, level);
1467 nilfs_bmap_sub_blocks(bmap, stats.bs_nblocks);
1470 nilfs_btree_clear_path(btree, path);
1471 nilfs_btree_free_path(btree, path);
1475 static int nilfs_btree_last_key(const struct nilfs_bmap *bmap, __u64 *keyp)
1477 struct nilfs_btree *btree;
1478 struct nilfs_btree_path *path;
1481 btree = (struct nilfs_btree *)bmap;
1482 path = nilfs_btree_alloc_path(btree);
1485 nilfs_btree_init_path(btree, path);
1487 ret = nilfs_btree_do_lookup_last(btree, path, keyp, NULL);
1489 nilfs_btree_clear_path(btree, path);
1490 nilfs_btree_free_path(btree, path);
1495 static int nilfs_btree_check_delete(struct nilfs_bmap *bmap, __u64 key)
1497 struct buffer_head *bh;
1498 struct nilfs_btree *btree;
1499 struct nilfs_btree_node *root, *node;
1500 __u64 maxkey, nextmaxkey;
1504 btree = (struct nilfs_btree *)bmap;
1505 root = nilfs_btree_get_root(btree);
1506 switch (nilfs_btree_height(btree)) {
1512 nchildren = nilfs_btree_node_get_nchildren(btree, root);
1515 ptr = nilfs_btree_node_get_ptr(btree, root, nchildren - 1);
1516 ret = nilfs_btree_get_block(btree, ptr, &bh);
1519 node = (struct nilfs_btree_node *)bh->b_data;
1525 nchildren = nilfs_btree_node_get_nchildren(btree, node);
1526 maxkey = nilfs_btree_node_get_key(btree, node, nchildren - 1);
1527 nextmaxkey = (nchildren > 1) ?
1528 nilfs_btree_node_get_key(btree, node, nchildren - 2) : 0;
1532 return (maxkey == key) && (nextmaxkey < bmap->b_low);
1535 static int nilfs_btree_gather_data(struct nilfs_bmap *bmap,
1536 __u64 *keys, __u64 *ptrs, int nitems)
1538 struct buffer_head *bh;
1539 struct nilfs_btree *btree;
1540 struct nilfs_btree_node *node, *root;
1544 int nchildren, i, ret;
1546 btree = (struct nilfs_btree *)bmap;
1547 root = nilfs_btree_get_root(btree);
1548 switch (nilfs_btree_height(btree)) {
1554 nchildren = nilfs_btree_node_get_nchildren(btree, root);
1555 WARN_ON(nchildren > 1);
1556 ptr = nilfs_btree_node_get_ptr(btree, root, nchildren - 1);
1557 ret = nilfs_btree_get_block(btree, ptr, &bh);
1560 node = (struct nilfs_btree_node *)bh->b_data;
1567 nchildren = nilfs_btree_node_get_nchildren(btree, node);
1568 if (nchildren < nitems)
1570 dkeys = nilfs_btree_node_dkeys(btree, node);
1571 dptrs = nilfs_btree_node_dptrs(btree, node);
1572 for (i = 0; i < nitems; i++) {
1573 keys[i] = nilfs_bmap_dkey_to_key(dkeys[i]);
1574 ptrs[i] = nilfs_bmap_dptr_to_ptr(dptrs[i]);
1584 nilfs_btree_prepare_convert_and_insert(struct nilfs_bmap *bmap, __u64 key,
1585 union nilfs_bmap_ptr_req *dreq,
1586 union nilfs_bmap_ptr_req *nreq,
1587 struct buffer_head **bhp,
1588 struct nilfs_bmap_stats *stats)
1590 struct buffer_head *bh;
1591 struct nilfs_btree *btree;
1594 btree = (struct nilfs_btree *)bmap;
1595 stats->bs_nblocks = 0;
1598 /* cannot find near ptr */
1599 if (btree->bt_ops->btop_find_target != NULL)
1601 = btree->bt_ops->btop_find_target(btree, NULL, key);
1602 ret = bmap->b_pops->bpop_prepare_alloc_ptr(bmap, dreq);
1607 stats->bs_nblocks++;
1609 nreq->bpr_ptr = dreq->bpr_ptr + 1;
1610 ret = bmap->b_pops->bpop_prepare_alloc_ptr(bmap, nreq);
1614 ret = nilfs_btree_get_new_block(btree, nreq->bpr_ptr, &bh);
1619 stats->bs_nblocks++;
1627 bmap->b_pops->bpop_abort_alloc_ptr(bmap, nreq);
1629 bmap->b_pops->bpop_abort_alloc_ptr(bmap, dreq);
1630 stats->bs_nblocks = 0;
1636 nilfs_btree_commit_convert_and_insert(struct nilfs_bmap *bmap,
1637 __u64 key, __u64 ptr,
1638 const __u64 *keys, const __u64 *ptrs,
1639 int n, __u64 low, __u64 high,
1640 union nilfs_bmap_ptr_req *dreq,
1641 union nilfs_bmap_ptr_req *nreq,
1642 struct buffer_head *bh)
1644 struct nilfs_btree *btree;
1645 struct nilfs_btree_node *node;
1648 /* free resources */
1649 if (bmap->b_ops->bop_clear != NULL)
1650 bmap->b_ops->bop_clear(bmap);
1652 /* ptr must be a pointer to a buffer head. */
1653 set_buffer_nilfs_volatile((struct buffer_head *)((unsigned long)ptr));
1655 /* convert and insert */
1656 btree = (struct nilfs_btree *)bmap;
1657 nilfs_btree_init(bmap, low, high);
1659 if (bmap->b_pops->bpop_commit_alloc_ptr != NULL) {
1660 bmap->b_pops->bpop_commit_alloc_ptr(bmap, dreq);
1661 bmap->b_pops->bpop_commit_alloc_ptr(bmap, nreq);
1664 /* create child node at level 1 */
1666 node = (struct nilfs_btree_node *)bh->b_data;
1667 nilfs_btree_node_init(btree, node, 0, 1, n, keys, ptrs);
1668 nilfs_btree_node_insert(btree, node,
1669 key, dreq->bpr_ptr, n);
1670 if (!buffer_dirty(bh))
1671 nilfs_btnode_mark_dirty(bh);
1672 if (!nilfs_bmap_dirty(bmap))
1673 nilfs_bmap_set_dirty(bmap);
1678 /* create root node at level 2 */
1679 node = nilfs_btree_get_root(btree);
1680 tmpptr = nreq->bpr_ptr;
1681 nilfs_btree_node_init(btree, node, NILFS_BTREE_NODE_ROOT,
1682 2, 1, &keys[0], &tmpptr);
1684 if (bmap->b_pops->bpop_commit_alloc_ptr != NULL)
1685 bmap->b_pops->bpop_commit_alloc_ptr(bmap, dreq);
1687 /* create root node at level 1 */
1688 node = nilfs_btree_get_root(btree);
1689 nilfs_btree_node_init(btree, node, NILFS_BTREE_NODE_ROOT,
1691 nilfs_btree_node_insert(btree, node,
1692 key, dreq->bpr_ptr, n);
1693 if (!nilfs_bmap_dirty(bmap))
1694 nilfs_bmap_set_dirty(bmap);
1697 if (btree->bt_ops->btop_set_target != NULL)
1698 btree->bt_ops->btop_set_target(btree, key, dreq->bpr_ptr);
1702 * nilfs_btree_convert_and_insert -
1712 int nilfs_btree_convert_and_insert(struct nilfs_bmap *bmap,
1713 __u64 key, __u64 ptr,
1714 const __u64 *keys, const __u64 *ptrs,
1715 int n, __u64 low, __u64 high)
1717 struct buffer_head *bh;
1718 union nilfs_bmap_ptr_req dreq, nreq, *di, *ni;
1719 struct nilfs_bmap_stats stats;
1722 if (n + 1 <= NILFS_BTREE_ROOT_NCHILDREN_MAX) {
1725 } else if ((n + 1) <= NILFS_BTREE_NODE_NCHILDREN_MAX(
1726 1 << bmap->b_inode->i_blkbits)) {
1735 ret = nilfs_btree_prepare_convert_and_insert(bmap, key, di, ni, &bh,
1739 nilfs_btree_commit_convert_and_insert(bmap, key, ptr, keys, ptrs, n,
1740 low, high, di, ni, bh);
1741 nilfs_bmap_add_blocks(bmap, stats.bs_nblocks);
1745 static int nilfs_btree_propagate_p(struct nilfs_btree *btree,
1746 struct nilfs_btree_path *path,
1748 struct buffer_head *bh)
1750 while ((++level < nilfs_btree_height(btree) - 1) &&
1751 !buffer_dirty(path[level].bp_bh))
1752 nilfs_btnode_mark_dirty(path[level].bp_bh);
1757 static int nilfs_btree_prepare_update_v(struct nilfs_btree *btree,
1758 struct nilfs_btree_path *path,
1761 struct nilfs_btree_node *parent;
1764 parent = nilfs_btree_get_node(btree, path, level + 1);
1765 path[level].bp_oldreq.bpr_ptr =
1766 nilfs_btree_node_get_ptr(btree, parent,
1767 path[level + 1].bp_index);
1768 path[level].bp_newreq.bpr_ptr = path[level].bp_oldreq.bpr_ptr + 1;
1769 ret = nilfs_bmap_prepare_update(&btree->bt_bmap,
1770 &path[level].bp_oldreq,
1771 &path[level].bp_newreq);
1775 if (buffer_nilfs_node(path[level].bp_bh)) {
1776 path[level].bp_ctxt.oldkey = path[level].bp_oldreq.bpr_ptr;
1777 path[level].bp_ctxt.newkey = path[level].bp_newreq.bpr_ptr;
1778 path[level].bp_ctxt.bh = path[level].bp_bh;
1779 ret = nilfs_btnode_prepare_change_key(
1780 &NILFS_BMAP_I(&btree->bt_bmap)->i_btnode_cache,
1781 &path[level].bp_ctxt);
1783 nilfs_bmap_abort_update(&btree->bt_bmap,
1784 &path[level].bp_oldreq,
1785 &path[level].bp_newreq);
1793 static void nilfs_btree_commit_update_v(struct nilfs_btree *btree,
1794 struct nilfs_btree_path *path,
1797 struct nilfs_btree_node *parent;
1799 nilfs_bmap_commit_update(&btree->bt_bmap,
1800 &path[level].bp_oldreq,
1801 &path[level].bp_newreq);
1803 if (buffer_nilfs_node(path[level].bp_bh)) {
1804 nilfs_btnode_commit_change_key(
1805 &NILFS_BMAP_I(&btree->bt_bmap)->i_btnode_cache,
1806 &path[level].bp_ctxt);
1807 path[level].bp_bh = path[level].bp_ctxt.bh;
1809 set_buffer_nilfs_volatile(path[level].bp_bh);
1811 parent = nilfs_btree_get_node(btree, path, level + 1);
1812 nilfs_btree_node_set_ptr(btree, parent, path[level + 1].bp_index,
1813 path[level].bp_newreq.bpr_ptr);
1816 static void nilfs_btree_abort_update_v(struct nilfs_btree *btree,
1817 struct nilfs_btree_path *path,
1820 nilfs_bmap_abort_update(&btree->bt_bmap,
1821 &path[level].bp_oldreq,
1822 &path[level].bp_newreq);
1823 if (buffer_nilfs_node(path[level].bp_bh))
1824 nilfs_btnode_abort_change_key(
1825 &NILFS_BMAP_I(&btree->bt_bmap)->i_btnode_cache,
1826 &path[level].bp_ctxt);
1829 static int nilfs_btree_prepare_propagate_v(struct nilfs_btree *btree,
1830 struct nilfs_btree_path *path,
1837 if (!buffer_nilfs_volatile(path[level].bp_bh)) {
1838 ret = nilfs_btree_prepare_update_v(btree, path, level);
1842 while ((++level < nilfs_btree_height(btree) - 1) &&
1843 !buffer_dirty(path[level].bp_bh)) {
1845 WARN_ON(buffer_nilfs_volatile(path[level].bp_bh));
1846 ret = nilfs_btree_prepare_update_v(btree, path, level);
1852 *maxlevelp = level - 1;
1857 while (--level > minlevel)
1858 nilfs_btree_abort_update_v(btree, path, level);
1859 if (!buffer_nilfs_volatile(path[level].bp_bh))
1860 nilfs_btree_abort_update_v(btree, path, level);
1864 static void nilfs_btree_commit_propagate_v(struct nilfs_btree *btree,
1865 struct nilfs_btree_path *path,
1868 struct buffer_head *bh)
1872 if (!buffer_nilfs_volatile(path[minlevel].bp_bh))
1873 nilfs_btree_commit_update_v(btree, path, minlevel);
1875 for (level = minlevel + 1; level <= maxlevel; level++)
1876 nilfs_btree_commit_update_v(btree, path, level);
1879 static int nilfs_btree_propagate_v(struct nilfs_btree *btree,
1880 struct nilfs_btree_path *path,
1882 struct buffer_head *bh)
1885 struct nilfs_btree_node *parent;
1889 path[level].bp_bh = bh;
1890 ret = nilfs_btree_prepare_propagate_v(btree, path, level, &maxlevel);
1894 if (buffer_nilfs_volatile(path[level].bp_bh)) {
1895 parent = nilfs_btree_get_node(btree, path, level + 1);
1896 ptr = nilfs_btree_node_get_ptr(btree, parent,
1897 path[level + 1].bp_index);
1898 ret = nilfs_bmap_mark_dirty(&btree->bt_bmap, ptr);
1903 nilfs_btree_commit_propagate_v(btree, path, level, maxlevel, bh);
1906 brelse(path[level].bp_bh);
1907 path[level].bp_bh = NULL;
1911 static int nilfs_btree_propagate(const struct nilfs_bmap *bmap,
1912 struct buffer_head *bh)
1914 struct nilfs_btree *btree;
1915 struct nilfs_btree_path *path;
1916 struct nilfs_btree_node *node;
1920 WARN_ON(!buffer_dirty(bh));
1922 btree = (struct nilfs_btree *)bmap;
1923 path = nilfs_btree_alloc_path(btree);
1926 nilfs_btree_init_path(btree, path);
1928 if (buffer_nilfs_node(bh)) {
1929 node = (struct nilfs_btree_node *)bh->b_data;
1930 key = nilfs_btree_node_get_key(btree, node, 0);
1931 level = nilfs_btree_node_get_level(btree, node);
1933 key = nilfs_bmap_data_get_key(bmap, bh);
1934 level = NILFS_BTREE_LEVEL_DATA;
1937 ret = nilfs_btree_do_lookup(btree, path, key, NULL, level + 1);
1939 if (unlikely(ret == -ENOENT))
1940 printk(KERN_CRIT "%s: key = %llu, level == %d\n",
1941 __func__, (unsigned long long)key, level);
1945 ret = btree->bt_ops->btop_propagate(btree, path, level, bh);
1948 nilfs_btree_clear_path(btree, path);
1949 nilfs_btree_free_path(btree, path);
1954 static int nilfs_btree_propagate_gc(const struct nilfs_bmap *bmap,
1955 struct buffer_head *bh)
1957 return nilfs_bmap_mark_dirty(bmap, bh->b_blocknr);
1960 static void nilfs_btree_add_dirty_buffer(struct nilfs_btree *btree,
1961 struct list_head *lists,
1962 struct buffer_head *bh)
1964 struct list_head *head;
1965 struct buffer_head *cbh;
1966 struct nilfs_btree_node *node, *cnode;
1971 node = (struct nilfs_btree_node *)bh->b_data;
1972 key = nilfs_btree_node_get_key(btree, node, 0);
1973 level = nilfs_btree_node_get_level(btree, node);
1974 list_for_each(head, &lists[level]) {
1975 cbh = list_entry(head, struct buffer_head, b_assoc_buffers);
1976 cnode = (struct nilfs_btree_node *)cbh->b_data;
1977 ckey = nilfs_btree_node_get_key(btree, cnode, 0);
1981 list_add_tail(&bh->b_assoc_buffers, head);
1984 static void nilfs_btree_lookup_dirty_buffers(struct nilfs_bmap *bmap,
1985 struct list_head *listp)
1987 struct nilfs_btree *btree = (struct nilfs_btree *)bmap;
1988 struct address_space *btcache = &NILFS_BMAP_I(bmap)->i_btnode_cache;
1989 struct list_head lists[NILFS_BTREE_LEVEL_MAX];
1990 struct pagevec pvec;
1991 struct buffer_head *bh, *head;
1995 for (level = NILFS_BTREE_LEVEL_NODE_MIN;
1996 level < NILFS_BTREE_LEVEL_MAX;
1998 INIT_LIST_HEAD(&lists[level]);
2000 pagevec_init(&pvec, 0);
2002 while (pagevec_lookup_tag(&pvec, btcache, &index, PAGECACHE_TAG_DIRTY,
2004 for (i = 0; i < pagevec_count(&pvec); i++) {
2005 bh = head = page_buffers(pvec.pages[i]);
2007 if (buffer_dirty(bh))
2008 nilfs_btree_add_dirty_buffer(btree,
2010 } while ((bh = bh->b_this_page) != head);
2012 pagevec_release(&pvec);
2016 for (level = NILFS_BTREE_LEVEL_NODE_MIN;
2017 level < NILFS_BTREE_LEVEL_MAX;
2019 list_splice(&lists[level], listp->prev);
2022 static int nilfs_btree_assign_p(struct nilfs_btree *btree,
2023 struct nilfs_btree_path *path,
2025 struct buffer_head **bh,
2027 union nilfs_binfo *binfo)
2029 struct nilfs_btree_node *parent;
2034 parent = nilfs_btree_get_node(btree, path, level + 1);
2035 ptr = nilfs_btree_node_get_ptr(btree, parent,
2036 path[level + 1].bp_index);
2037 if (buffer_nilfs_node(*bh)) {
2038 path[level].bp_ctxt.oldkey = ptr;
2039 path[level].bp_ctxt.newkey = blocknr;
2040 path[level].bp_ctxt.bh = *bh;
2041 ret = nilfs_btnode_prepare_change_key(
2042 &NILFS_BMAP_I(&btree->bt_bmap)->i_btnode_cache,
2043 &path[level].bp_ctxt);
2046 nilfs_btnode_commit_change_key(
2047 &NILFS_BMAP_I(&btree->bt_bmap)->i_btnode_cache,
2048 &path[level].bp_ctxt);
2049 *bh = path[level].bp_ctxt.bh;
2052 nilfs_btree_node_set_ptr(btree, parent,
2053 path[level + 1].bp_index, blocknr);
2055 key = nilfs_btree_node_get_key(btree, parent,
2056 path[level + 1].bp_index);
2057 /* on-disk format */
2058 binfo->bi_dat.bi_blkoff = nilfs_bmap_key_to_dkey(key);
2059 binfo->bi_dat.bi_level = level;
2064 static int nilfs_btree_assign_v(struct nilfs_btree *btree,
2065 struct nilfs_btree_path *path,
2067 struct buffer_head **bh,
2069 union nilfs_binfo *binfo)
2071 struct nilfs_btree_node *parent;
2074 union nilfs_bmap_ptr_req req;
2077 parent = nilfs_btree_get_node(btree, path, level + 1);
2078 ptr = nilfs_btree_node_get_ptr(btree, parent,
2079 path[level + 1].bp_index);
2081 ret = nilfs_bmap_start_v(&btree->bt_bmap, &req, blocknr);
2082 if (unlikely(ret < 0))
2085 key = nilfs_btree_node_get_key(btree, parent,
2086 path[level + 1].bp_index);
2087 /* on-disk format */
2088 binfo->bi_v.bi_vblocknr = nilfs_bmap_ptr_to_dptr(ptr);
2089 binfo->bi_v.bi_blkoff = nilfs_bmap_key_to_dkey(key);
2094 static int nilfs_btree_assign(struct nilfs_bmap *bmap,
2095 struct buffer_head **bh,
2097 union nilfs_binfo *binfo)
2099 struct nilfs_btree *btree;
2100 struct nilfs_btree_path *path;
2101 struct nilfs_btree_node *node;
2105 btree = (struct nilfs_btree *)bmap;
2106 path = nilfs_btree_alloc_path(btree);
2109 nilfs_btree_init_path(btree, path);
2111 if (buffer_nilfs_node(*bh)) {
2112 node = (struct nilfs_btree_node *)(*bh)->b_data;
2113 key = nilfs_btree_node_get_key(btree, node, 0);
2114 level = nilfs_btree_node_get_level(btree, node);
2116 key = nilfs_bmap_data_get_key(bmap, *bh);
2117 level = NILFS_BTREE_LEVEL_DATA;
2120 ret = nilfs_btree_do_lookup(btree, path, key, NULL, level + 1);
2122 WARN_ON(ret == -ENOENT);
2126 ret = btree->bt_ops->btop_assign(btree, path, level, bh,
2130 nilfs_btree_clear_path(btree, path);
2131 nilfs_btree_free_path(btree, path);
2136 static int nilfs_btree_assign_gc(struct nilfs_bmap *bmap,
2137 struct buffer_head **bh,
2139 union nilfs_binfo *binfo)
2141 struct nilfs_btree *btree;
2142 struct nilfs_btree_node *node;
2146 btree = (struct nilfs_btree *)bmap;
2147 ret = nilfs_bmap_move_v(bmap, (*bh)->b_blocknr, blocknr);
2151 if (buffer_nilfs_node(*bh)) {
2152 node = (struct nilfs_btree_node *)(*bh)->b_data;
2153 key = nilfs_btree_node_get_key(btree, node, 0);
2155 key = nilfs_bmap_data_get_key(bmap, *bh);
2157 /* on-disk format */
2158 binfo->bi_v.bi_vblocknr = cpu_to_le64((*bh)->b_blocknr);
2159 binfo->bi_v.bi_blkoff = nilfs_bmap_key_to_dkey(key);
2164 static int nilfs_btree_mark(struct nilfs_bmap *bmap, __u64 key, int level)
2166 struct buffer_head *bh;
2167 struct nilfs_btree *btree;
2168 struct nilfs_btree_path *path;
2172 btree = (struct nilfs_btree *)bmap;
2173 path = nilfs_btree_alloc_path(btree);
2176 nilfs_btree_init_path(btree, path);
2178 ret = nilfs_btree_do_lookup(btree, path, key, &ptr, level + 1);
2180 WARN_ON(ret == -ENOENT);
2183 ret = nilfs_btree_get_block(btree, ptr, &bh);
2185 WARN_ON(ret == -ENOENT);
2189 if (!buffer_dirty(bh))
2190 nilfs_btnode_mark_dirty(bh);
2192 if (!nilfs_bmap_dirty(&btree->bt_bmap))
2193 nilfs_bmap_set_dirty(&btree->bt_bmap);
2196 nilfs_btree_clear_path(btree, path);
2197 nilfs_btree_free_path(btree, path);
2201 static const struct nilfs_bmap_operations nilfs_btree_ops = {
2202 .bop_lookup = nilfs_btree_lookup,
2203 .bop_insert = nilfs_btree_insert,
2204 .bop_delete = nilfs_btree_delete,
2207 .bop_propagate = nilfs_btree_propagate,
2209 .bop_lookup_dirty_buffers = nilfs_btree_lookup_dirty_buffers,
2211 .bop_assign = nilfs_btree_assign,
2212 .bop_mark = nilfs_btree_mark,
2214 .bop_last_key = nilfs_btree_last_key,
2215 .bop_check_insert = NULL,
2216 .bop_check_delete = nilfs_btree_check_delete,
2217 .bop_gather_data = nilfs_btree_gather_data,
2220 static const struct nilfs_bmap_operations nilfs_btree_ops_gc = {
2226 .bop_propagate = nilfs_btree_propagate_gc,
2228 .bop_lookup_dirty_buffers = nilfs_btree_lookup_dirty_buffers,
2230 .bop_assign = nilfs_btree_assign_gc,
2233 .bop_last_key = NULL,
2234 .bop_check_insert = NULL,
2235 .bop_check_delete = NULL,
2236 .bop_gather_data = NULL,
2239 static const struct nilfs_btree_operations nilfs_btree_ops_v = {
2240 .btop_find_target = nilfs_btree_find_target_v,
2241 .btop_set_target = nilfs_btree_set_target_v,
2242 .btop_propagate = nilfs_btree_propagate_v,
2243 .btop_assign = nilfs_btree_assign_v,
2246 static const struct nilfs_btree_operations nilfs_btree_ops_p = {
2247 .btop_find_target = NULL,
2248 .btop_set_target = NULL,
2249 .btop_propagate = nilfs_btree_propagate_p,
2250 .btop_assign = nilfs_btree_assign_p,
2253 int nilfs_btree_init(struct nilfs_bmap *bmap, __u64 low, __u64 high)
2255 struct nilfs_btree *btree;
2257 btree = (struct nilfs_btree *)bmap;
2258 bmap->b_ops = &nilfs_btree_ops;
2260 bmap->b_high = high;
2261 switch (bmap->b_inode->i_ino) {
2263 btree->bt_ops = &nilfs_btree_ops_p;
2266 btree->bt_ops = &nilfs_btree_ops_v;
2273 void nilfs_btree_init_gc(struct nilfs_bmap *bmap)
2275 bmap->b_low = NILFS_BMAP_LARGE_LOW;
2276 bmap->b_high = NILFS_BMAP_LARGE_HIGH;
2277 bmap->b_ops = &nilfs_btree_ops_gc;