4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or https://opensource.org/licenses/CDDL-1.0.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
22 * Copyright 2009 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
26 * Copyright (c) 2013, 2019 by Delphix. All rights reserved.
27 * Copyright (c) 2015, Nexenta Systems, Inc. All rights reserved.
30 #include <sys/zfs_context.h>
33 #include <sys/dnode.h>
35 #include <sys/range_tree.h>
38 * Range trees are tree-based data structures that can be used to
39 * track free space or generally any space allocation information.
40 * A range tree keeps track of individual segments and automatically
41 * provides facilities such as adjacent extent merging and extent
42 * splitting in response to range add/remove requests.
44 * A range tree starts out completely empty, with no segments in it.
45 * Adding an allocation via range_tree_add to the range tree can either:
46 * 1) create a new extent
47 * 2) extend an adjacent extent
48 * 3) merge two adjacent extents
49 * Conversely, removing an allocation via range_tree_remove can:
50 * 1) completely remove an extent
51 * 2) shorten an extent (if the allocation was near one of its ends)
52 * 3) split an extent into two extents, in effect punching a hole
54 * A range tree is also capable of 'bridging' gaps when adding
55 * allocations. This is useful for cases when close proximity of
56 * allocations is an important detail that needs to be represented
57 * in the range tree. See range_tree_set_gap(). The default behavior
58 * is not to bridge gaps (i.e. the maximum allowed gap size is 0).
60 * In order to traverse a range tree, use either the range_tree_walk()
61 * or range_tree_vacate() functions.
63 * To obtain more accurate information on individual segment
64 * operations that the range tree performs "under the hood", you can
65 * specify a set of callbacks by passing a range_tree_ops_t structure
66 * to the range_tree_create function. Any callbacks that are non-NULL
67 * are then called at the appropriate times.
69 * The range tree code also supports a special variant of range trees
70 * that can bridge small gaps between segments. This kind of tree is used
71 * by the dsl scanning code to group I/Os into mostly sequential chunks to
72 * optimize disk performance. The code here attempts to do this with as
73 * little memory and computational overhead as possible. One limitation of
74 * this implementation is that segments of range trees with gaps can only
75 * support removing complete segments.
79 rs_copy(range_seg_t *src, range_seg_t *dest, range_tree_t *rt)
81 ASSERT3U(rt->rt_type, <, RANGE_SEG_NUM_TYPES);
83 switch (rt->rt_type) {
85 size = sizeof (range_seg32_t);
88 size = sizeof (range_seg64_t);
91 size = sizeof (range_seg_gap_t);
94 __builtin_unreachable();
96 memcpy(dest, src, size);
100 range_tree_stat_verify(range_tree_t *rt)
103 zfs_btree_index_t where;
104 uint64_t hist[RANGE_TREE_HISTOGRAM_SIZE] = { 0 };
107 for (rs = zfs_btree_first(&rt->rt_root, &where); rs != NULL;
108 rs = zfs_btree_next(&rt->rt_root, &where, &where)) {
109 uint64_t size = rs_get_end(rs, rt) - rs_get_start(rs, rt);
110 int idx = highbit64(size) - 1;
113 ASSERT3U(hist[idx], !=, 0);
116 for (i = 0; i < RANGE_TREE_HISTOGRAM_SIZE; i++) {
117 if (hist[i] != rt->rt_histogram[i]) {
118 zfs_dbgmsg("i=%d, hist=%px, hist=%llu, rt_hist=%llu",
119 i, hist, (u_longlong_t)hist[i],
120 (u_longlong_t)rt->rt_histogram[i]);
122 VERIFY3U(hist[i], ==, rt->rt_histogram[i]);
127 range_tree_stat_incr(range_tree_t *rt, range_seg_t *rs)
129 uint64_t size = rs_get_end(rs, rt) - rs_get_start(rs, rt);
130 int idx = highbit64(size) - 1;
134 sizeof (rt->rt_histogram) / sizeof (*rt->rt_histogram));
136 rt->rt_histogram[idx]++;
137 ASSERT3U(rt->rt_histogram[idx], !=, 0);
141 range_tree_stat_decr(range_tree_t *rt, range_seg_t *rs)
143 uint64_t size = rs_get_end(rs, rt) - rs_get_start(rs, rt);
144 int idx = highbit64(size) - 1;
148 sizeof (rt->rt_histogram) / sizeof (*rt->rt_histogram));
150 ASSERT3U(rt->rt_histogram[idx], !=, 0);
151 rt->rt_histogram[idx]--;
154 __attribute__((always_inline)) inline
156 range_tree_seg32_compare(const void *x1, const void *x2)
158 const range_seg32_t *r1 = x1;
159 const range_seg32_t *r2 = x2;
161 ASSERT3U(r1->rs_start, <=, r1->rs_end);
162 ASSERT3U(r2->rs_start, <=, r2->rs_end);
164 return ((r1->rs_start >= r2->rs_end) - (r1->rs_end <= r2->rs_start));
167 __attribute__((always_inline)) inline
169 range_tree_seg64_compare(const void *x1, const void *x2)
171 const range_seg64_t *r1 = x1;
172 const range_seg64_t *r2 = x2;
174 ASSERT3U(r1->rs_start, <=, r1->rs_end);
175 ASSERT3U(r2->rs_start, <=, r2->rs_end);
177 return ((r1->rs_start >= r2->rs_end) - (r1->rs_end <= r2->rs_start));
180 __attribute__((always_inline)) inline
182 range_tree_seg_gap_compare(const void *x1, const void *x2)
184 const range_seg_gap_t *r1 = x1;
185 const range_seg_gap_t *r2 = x2;
187 ASSERT3U(r1->rs_start, <=, r1->rs_end);
188 ASSERT3U(r2->rs_start, <=, r2->rs_end);
190 return ((r1->rs_start >= r2->rs_end) - (r1->rs_end <= r2->rs_start));
193 ZFS_BTREE_FIND_IN_BUF_FUNC(range_tree_seg32_find_in_buf, range_seg32_t,
194 range_tree_seg32_compare)
196 ZFS_BTREE_FIND_IN_BUF_FUNC(range_tree_seg64_find_in_buf, range_seg64_t,
197 range_tree_seg64_compare)
199 ZFS_BTREE_FIND_IN_BUF_FUNC(range_tree_seg_gap_find_in_buf, range_seg_gap_t,
200 range_tree_seg_gap_compare)
203 range_tree_create_gap(const range_tree_ops_t *ops, range_seg_type_t type,
204 void *arg, uint64_t start, uint64_t shift, uint64_t gap)
206 range_tree_t *rt = kmem_zalloc(sizeof (range_tree_t), KM_SLEEP);
208 ASSERT3U(shift, <, 64);
209 ASSERT3U(type, <=, RANGE_SEG_NUM_TYPES);
211 int (*compare) (const void *, const void *);
212 bt_find_in_buf_f bt_find;
215 size = sizeof (range_seg32_t);
216 compare = range_tree_seg32_compare;
217 bt_find = range_tree_seg32_find_in_buf;
220 size = sizeof (range_seg64_t);
221 compare = range_tree_seg64_compare;
222 bt_find = range_tree_seg64_find_in_buf;
225 size = sizeof (range_seg_gap_t);
226 compare = range_tree_seg_gap_compare;
227 bt_find = range_tree_seg_gap_find_in_buf;
230 panic("Invalid range seg type %d", type);
232 zfs_btree_create(&rt->rt_root, compare, bt_find, size);
238 rt->rt_start = start;
239 rt->rt_shift = shift;
241 if (rt->rt_ops != NULL && rt->rt_ops->rtop_create != NULL)
242 rt->rt_ops->rtop_create(rt, rt->rt_arg);
248 range_tree_create(const range_tree_ops_t *ops, range_seg_type_t type,
249 void *arg, uint64_t start, uint64_t shift)
251 return (range_tree_create_gap(ops, type, arg, start, shift, 0));
255 range_tree_destroy(range_tree_t *rt)
257 VERIFY0(rt->rt_space);
259 if (rt->rt_ops != NULL && rt->rt_ops->rtop_destroy != NULL)
260 rt->rt_ops->rtop_destroy(rt, rt->rt_arg);
262 zfs_btree_destroy(&rt->rt_root);
263 kmem_free(rt, sizeof (*rt));
267 range_tree_adjust_fill(range_tree_t *rt, range_seg_t *rs, int64_t delta)
269 if (delta < 0 && delta * -1 >= rs_get_fill(rs, rt)) {
270 zfs_panic_recover("zfs: attempting to decrease fill to or "
271 "below 0; probable double remove in segment [%llx:%llx]",
272 (longlong_t)rs_get_start(rs, rt),
273 (longlong_t)rs_get_end(rs, rt));
275 if (rs_get_fill(rs, rt) + delta > rs_get_end(rs, rt) -
276 rs_get_start(rs, rt)) {
277 zfs_panic_recover("zfs: attempting to increase fill beyond "
278 "max; probable double add in segment [%llx:%llx]",
279 (longlong_t)rs_get_start(rs, rt),
280 (longlong_t)rs_get_end(rs, rt));
283 if (rt->rt_ops != NULL && rt->rt_ops->rtop_remove != NULL)
284 rt->rt_ops->rtop_remove(rt, rs, rt->rt_arg);
285 rs_set_fill(rs, rt, rs_get_fill(rs, rt) + delta);
286 if (rt->rt_ops != NULL && rt->rt_ops->rtop_add != NULL)
287 rt->rt_ops->rtop_add(rt, rs, rt->rt_arg);
291 range_tree_add_impl(void *arg, uint64_t start, uint64_t size, uint64_t fill)
293 range_tree_t *rt = arg;
294 zfs_btree_index_t where;
295 range_seg_t *rs_before, *rs_after, *rs;
296 range_seg_max_t tmp, rsearch;
297 uint64_t end = start + size, gap = rt->rt_gap;
298 uint64_t bridge_size = 0;
299 boolean_t merge_before, merge_after;
301 ASSERT3U(size, !=, 0);
302 ASSERT3U(fill, <=, size);
303 ASSERT3U(start + size, >, start);
305 rs_set_start(&rsearch, rt, start);
306 rs_set_end(&rsearch, rt, end);
307 rs = zfs_btree_find(&rt->rt_root, &rsearch, &where);
310 * If this is a gap-supporting range tree, it is possible that we
311 * are inserting into an existing segment. In this case simply
312 * bump the fill count and call the remove / add callbacks. If the
313 * new range will extend an existing segment, we remove the
314 * existing one, apply the new extent to it and re-insert it using
315 * the normal code paths.
319 zfs_panic_recover("zfs: adding existent segment to "
320 "range tree (offset=%llx size=%llx)",
321 (longlong_t)start, (longlong_t)size);
324 uint64_t rstart = rs_get_start(rs, rt);
325 uint64_t rend = rs_get_end(rs, rt);
326 if (rstart <= start && rend >= end) {
327 range_tree_adjust_fill(rt, rs, fill);
331 if (rt->rt_ops != NULL && rt->rt_ops->rtop_remove != NULL)
332 rt->rt_ops->rtop_remove(rt, rs, rt->rt_arg);
334 range_tree_stat_decr(rt, rs);
335 rt->rt_space -= rend - rstart;
337 fill += rs_get_fill(rs, rt);
338 start = MIN(start, rstart);
339 end = MAX(end, rend);
342 zfs_btree_remove(&rt->rt_root, rs);
343 range_tree_add_impl(rt, start, size, fill);
347 ASSERT3P(rs, ==, NULL);
350 * Determine whether or not we will have to merge with our neighbors.
351 * If gap != 0, we might need to merge with our neighbors even if we
352 * aren't directly touching.
354 zfs_btree_index_t where_before, where_after;
355 rs_before = zfs_btree_prev(&rt->rt_root, &where, &where_before);
356 rs_after = zfs_btree_next(&rt->rt_root, &where, &where_after);
358 merge_before = (rs_before != NULL && rs_get_end(rs_before, rt) >=
360 merge_after = (rs_after != NULL && rs_get_start(rs_after, rt) <= end +
363 if (merge_before && gap != 0)
364 bridge_size += start - rs_get_end(rs_before, rt);
365 if (merge_after && gap != 0)
366 bridge_size += rs_get_start(rs_after, rt) - end;
368 if (merge_before && merge_after) {
369 if (rt->rt_ops != NULL && rt->rt_ops->rtop_remove != NULL) {
370 rt->rt_ops->rtop_remove(rt, rs_before, rt->rt_arg);
371 rt->rt_ops->rtop_remove(rt, rs_after, rt->rt_arg);
374 range_tree_stat_decr(rt, rs_before);
375 range_tree_stat_decr(rt, rs_after);
377 rs_copy(rs_after, &tmp, rt);
378 uint64_t before_start = rs_get_start_raw(rs_before, rt);
379 uint64_t before_fill = rs_get_fill(rs_before, rt);
380 uint64_t after_fill = rs_get_fill(rs_after, rt);
381 zfs_btree_remove_idx(&rt->rt_root, &where_before);
384 * We have to re-find the node because our old reference is
385 * invalid as soon as we do any mutating btree operations.
387 rs_after = zfs_btree_find(&rt->rt_root, &tmp, &where_after);
388 ASSERT3P(rs_after, !=, NULL);
389 rs_set_start_raw(rs_after, rt, before_start);
390 rs_set_fill(rs_after, rt, after_fill + before_fill + fill);
392 } else if (merge_before) {
393 if (rt->rt_ops != NULL && rt->rt_ops->rtop_remove != NULL)
394 rt->rt_ops->rtop_remove(rt, rs_before, rt->rt_arg);
396 range_tree_stat_decr(rt, rs_before);
398 uint64_t before_fill = rs_get_fill(rs_before, rt);
399 rs_set_end(rs_before, rt, end);
400 rs_set_fill(rs_before, rt, before_fill + fill);
402 } else if (merge_after) {
403 if (rt->rt_ops != NULL && rt->rt_ops->rtop_remove != NULL)
404 rt->rt_ops->rtop_remove(rt, rs_after, rt->rt_arg);
406 range_tree_stat_decr(rt, rs_after);
408 uint64_t after_fill = rs_get_fill(rs_after, rt);
409 rs_set_start(rs_after, rt, start);
410 rs_set_fill(rs_after, rt, after_fill + fill);
415 rs_set_start(rs, rt, start);
416 rs_set_end(rs, rt, end);
417 rs_set_fill(rs, rt, fill);
418 zfs_btree_add_idx(&rt->rt_root, rs, &where);
422 ASSERT3U(rs_get_fill(rs, rt), <=, rs_get_end(rs, rt) -
423 rs_get_start(rs, rt));
425 ASSERT3U(rs_get_fill(rs, rt), ==, rs_get_end(rs, rt) -
426 rs_get_start(rs, rt));
429 if (rt->rt_ops != NULL && rt->rt_ops->rtop_add != NULL)
430 rt->rt_ops->rtop_add(rt, rs, rt->rt_arg);
432 range_tree_stat_incr(rt, rs);
433 rt->rt_space += size + bridge_size;
437 range_tree_add(void *arg, uint64_t start, uint64_t size)
439 range_tree_add_impl(arg, start, size, size);
443 range_tree_remove_impl(range_tree_t *rt, uint64_t start, uint64_t size,
446 zfs_btree_index_t where;
448 range_seg_max_t rsearch, rs_tmp;
449 uint64_t end = start + size;
450 boolean_t left_over, right_over;
452 VERIFY3U(size, !=, 0);
453 VERIFY3U(size, <=, rt->rt_space);
454 if (rt->rt_type == RANGE_SEG64)
455 ASSERT3U(start + size, >, start);
457 rs_set_start(&rsearch, rt, start);
458 rs_set_end(&rsearch, rt, end);
459 rs = zfs_btree_find(&rt->rt_root, &rsearch, &where);
461 /* Make sure we completely overlap with someone */
463 zfs_panic_recover("zfs: removing nonexistent segment from "
464 "range tree (offset=%llx size=%llx)",
465 (longlong_t)start, (longlong_t)size);
470 * Range trees with gap support must only remove complete segments
471 * from the tree. This allows us to maintain accurate fill accounting
472 * and to ensure that bridged sections are not leaked. If we need to
473 * remove less than the full segment, we can only adjust the fill count.
475 if (rt->rt_gap != 0) {
477 if (rs_get_fill(rs, rt) == size) {
478 start = rs_get_start(rs, rt);
479 end = rs_get_end(rs, rt);
482 range_tree_adjust_fill(rt, rs, -size);
485 } else if (rs_get_start(rs, rt) != start ||
486 rs_get_end(rs, rt) != end) {
487 zfs_panic_recover("zfs: freeing partial segment of "
488 "gap tree (offset=%llx size=%llx) of "
489 "(offset=%llx size=%llx)",
490 (longlong_t)start, (longlong_t)size,
491 (longlong_t)rs_get_start(rs, rt),
492 (longlong_t)rs_get_end(rs, rt) - rs_get_start(rs,
498 VERIFY3U(rs_get_start(rs, rt), <=, start);
499 VERIFY3U(rs_get_end(rs, rt), >=, end);
501 left_over = (rs_get_start(rs, rt) != start);
502 right_over = (rs_get_end(rs, rt) != end);
504 range_tree_stat_decr(rt, rs);
506 if (rt->rt_ops != NULL && rt->rt_ops->rtop_remove != NULL)
507 rt->rt_ops->rtop_remove(rt, rs, rt->rt_arg);
509 if (left_over && right_over) {
510 range_seg_max_t newseg;
511 rs_set_start(&newseg, rt, end);
512 rs_set_end_raw(&newseg, rt, rs_get_end_raw(rs, rt));
513 rs_set_fill(&newseg, rt, rs_get_end(rs, rt) - end);
514 range_tree_stat_incr(rt, &newseg);
516 // This modifies the buffer already inside the range tree
517 rs_set_end(rs, rt, start);
519 rs_copy(rs, &rs_tmp, rt);
520 if (zfs_btree_next(&rt->rt_root, &where, &where) != NULL)
521 zfs_btree_add_idx(&rt->rt_root, &newseg, &where);
523 zfs_btree_add(&rt->rt_root, &newseg);
525 if (rt->rt_ops != NULL && rt->rt_ops->rtop_add != NULL)
526 rt->rt_ops->rtop_add(rt, &newseg, rt->rt_arg);
527 } else if (left_over) {
528 // This modifies the buffer already inside the range tree
529 rs_set_end(rs, rt, start);
530 rs_copy(rs, &rs_tmp, rt);
531 } else if (right_over) {
532 // This modifies the buffer already inside the range tree
533 rs_set_start(rs, rt, end);
534 rs_copy(rs, &rs_tmp, rt);
536 zfs_btree_remove_idx(&rt->rt_root, &where);
542 * The fill of the leftover segment will always be equal to
543 * the size, since we do not support removing partial segments
544 * of range trees with gaps.
546 rs_set_fill_raw(rs, rt, rs_get_end_raw(rs, rt) -
547 rs_get_start_raw(rs, rt));
548 range_tree_stat_incr(rt, &rs_tmp);
550 if (rt->rt_ops != NULL && rt->rt_ops->rtop_add != NULL)
551 rt->rt_ops->rtop_add(rt, &rs_tmp, rt->rt_arg);
554 rt->rt_space -= size;
558 range_tree_remove(void *arg, uint64_t start, uint64_t size)
560 range_tree_remove_impl(arg, start, size, B_FALSE);
564 range_tree_remove_fill(range_tree_t *rt, uint64_t start, uint64_t size)
566 range_tree_remove_impl(rt, start, size, B_TRUE);
570 range_tree_resize_segment(range_tree_t *rt, range_seg_t *rs,
571 uint64_t newstart, uint64_t newsize)
573 int64_t delta = newsize - (rs_get_end(rs, rt) - rs_get_start(rs, rt));
575 range_tree_stat_decr(rt, rs);
576 if (rt->rt_ops != NULL && rt->rt_ops->rtop_remove != NULL)
577 rt->rt_ops->rtop_remove(rt, rs, rt->rt_arg);
579 rs_set_start(rs, rt, newstart);
580 rs_set_end(rs, rt, newstart + newsize);
582 range_tree_stat_incr(rt, rs);
583 if (rt->rt_ops != NULL && rt->rt_ops->rtop_add != NULL)
584 rt->rt_ops->rtop_add(rt, rs, rt->rt_arg);
586 rt->rt_space += delta;
590 range_tree_find_impl(range_tree_t *rt, uint64_t start, uint64_t size)
592 range_seg_max_t rsearch;
593 uint64_t end = start + size;
597 rs_set_start(&rsearch, rt, start);
598 rs_set_end(&rsearch, rt, end);
599 return (zfs_btree_find(&rt->rt_root, &rsearch, NULL));
603 range_tree_find(range_tree_t *rt, uint64_t start, uint64_t size)
605 if (rt->rt_type == RANGE_SEG64)
606 ASSERT3U(start + size, >, start);
608 range_seg_t *rs = range_tree_find_impl(rt, start, size);
609 if (rs != NULL && rs_get_start(rs, rt) <= start &&
610 rs_get_end(rs, rt) >= start + size) {
617 range_tree_verify_not_present(range_tree_t *rt, uint64_t off, uint64_t size)
619 range_seg_t *rs = range_tree_find(rt, off, size);
621 panic("segment already in tree; rs=%p", (void *)rs);
625 range_tree_contains(range_tree_t *rt, uint64_t start, uint64_t size)
627 return (range_tree_find(rt, start, size) != NULL);
631 * Returns the first subset of the given range which overlaps with the range
632 * tree. Returns true if there is a segment in the range, and false if there
636 range_tree_find_in(range_tree_t *rt, uint64_t start, uint64_t size,
637 uint64_t *ostart, uint64_t *osize)
639 if (rt->rt_type == RANGE_SEG64)
640 ASSERT3U(start + size, >, start);
642 range_seg_max_t rsearch;
643 rs_set_start(&rsearch, rt, start);
644 rs_set_end_raw(&rsearch, rt, rs_get_start_raw(&rsearch, rt) + 1);
646 zfs_btree_index_t where;
647 range_seg_t *rs = zfs_btree_find(&rt->rt_root, &rsearch, &where);
650 *osize = MIN(size, rs_get_end(rs, rt) - start);
654 rs = zfs_btree_next(&rt->rt_root, &where, &where);
655 if (rs == NULL || rs_get_start(rs, rt) > start + size)
658 *ostart = rs_get_start(rs, rt);
659 *osize = MIN(start + size, rs_get_end(rs, rt)) -
660 rs_get_start(rs, rt);
665 * Ensure that this range is not in the tree, regardless of whether
666 * it is currently in the tree.
669 range_tree_clear(range_tree_t *rt, uint64_t start, uint64_t size)
676 if (rt->rt_type == RANGE_SEG64)
677 ASSERT3U(start + size, >, start);
679 while ((rs = range_tree_find_impl(rt, start, size)) != NULL) {
680 uint64_t free_start = MAX(rs_get_start(rs, rt), start);
681 uint64_t free_end = MIN(rs_get_end(rs, rt), start + size);
682 range_tree_remove(rt, free_start, free_end - free_start);
687 range_tree_swap(range_tree_t **rtsrc, range_tree_t **rtdst)
691 ASSERT0(range_tree_space(*rtdst));
692 ASSERT0(zfs_btree_numnodes(&(*rtdst)->rt_root));
700 range_tree_vacate(range_tree_t *rt, range_tree_func_t *func, void *arg)
702 if (rt->rt_ops != NULL && rt->rt_ops->rtop_vacate != NULL)
703 rt->rt_ops->rtop_vacate(rt, rt->rt_arg);
707 zfs_btree_index_t *cookie = NULL;
709 while ((rs = zfs_btree_destroy_nodes(&rt->rt_root, &cookie)) !=
711 func(arg, rs_get_start(rs, rt), rs_get_end(rs, rt) -
712 rs_get_start(rs, rt));
715 zfs_btree_clear(&rt->rt_root);
718 memset(rt->rt_histogram, 0, sizeof (rt->rt_histogram));
723 range_tree_walk(range_tree_t *rt, range_tree_func_t *func, void *arg)
725 zfs_btree_index_t where;
726 for (range_seg_t *rs = zfs_btree_first(&rt->rt_root, &where);
727 rs != NULL; rs = zfs_btree_next(&rt->rt_root, &where, &where)) {
728 func(arg, rs_get_start(rs, rt), rs_get_end(rs, rt) -
729 rs_get_start(rs, rt));
734 range_tree_first(range_tree_t *rt)
736 return (zfs_btree_first(&rt->rt_root, NULL));
740 range_tree_space(range_tree_t *rt)
742 return (rt->rt_space);
746 range_tree_numsegs(range_tree_t *rt)
748 return ((rt == NULL) ? 0 : zfs_btree_numnodes(&rt->rt_root));
752 range_tree_is_empty(range_tree_t *rt)
755 return (range_tree_space(rt) == 0);
759 * Remove any overlapping ranges between the given segment [start, end)
760 * from removefrom. Add non-overlapping leftovers to addto.
763 range_tree_remove_xor_add_segment(uint64_t start, uint64_t end,
764 range_tree_t *removefrom, range_tree_t *addto)
766 zfs_btree_index_t where;
767 range_seg_max_t starting_rs;
768 rs_set_start(&starting_rs, removefrom, start);
769 rs_set_end_raw(&starting_rs, removefrom, rs_get_start_raw(&starting_rs,
772 range_seg_t *curr = zfs_btree_find(&removefrom->rt_root,
773 &starting_rs, &where);
776 curr = zfs_btree_next(&removefrom->rt_root, &where, &where);
779 for (; curr != NULL; curr = next) {
782 VERIFY3U(start, <, end);
784 /* there is no overlap */
785 if (end <= rs_get_start(curr, removefrom)) {
786 range_tree_add(addto, start, end - start);
790 uint64_t overlap_start = MAX(rs_get_start(curr, removefrom),
792 uint64_t overlap_end = MIN(rs_get_end(curr, removefrom),
794 uint64_t overlap_size = overlap_end - overlap_start;
795 ASSERT3S(overlap_size, >, 0);
797 rs_copy(curr, &rs, removefrom);
799 range_tree_remove(removefrom, overlap_start, overlap_size);
801 if (start < overlap_start)
802 range_tree_add(addto, start, overlap_start - start);
805 next = zfs_btree_find(&removefrom->rt_root, &rs, &where);
807 * If we find something here, we only removed part of the
808 * curr segment. Either there's some left at the end
809 * because we've reached the end of the range we're removing,
810 * or there's some left at the start because we started
811 * partway through the range. Either way, we continue with
812 * the loop. If it's the former, we'll return at the start of
813 * the loop, and if it's the latter we'll see if there is more
817 ASSERT(start == end || start == rs_get_end(&rs,
821 next = zfs_btree_next(&removefrom->rt_root, &where, &where);
823 VERIFY3P(curr, ==, NULL);
826 VERIFY3U(start, <, end);
827 range_tree_add(addto, start, end - start);
829 VERIFY3U(start, ==, end);
834 * For each entry in rt, if it exists in removefrom, remove it
835 * from removefrom. Otherwise, add it to addto.
838 range_tree_remove_xor_add(range_tree_t *rt, range_tree_t *removefrom,
841 zfs_btree_index_t where;
842 for (range_seg_t *rs = zfs_btree_first(&rt->rt_root, &where); rs;
843 rs = zfs_btree_next(&rt->rt_root, &where, &where)) {
844 range_tree_remove_xor_add_segment(rs_get_start(rs, rt),
845 rs_get_end(rs, rt), removefrom, addto);
850 range_tree_min(range_tree_t *rt)
852 range_seg_t *rs = zfs_btree_first(&rt->rt_root, NULL);
853 return (rs != NULL ? rs_get_start(rs, rt) : 0);
857 range_tree_max(range_tree_t *rt)
859 range_seg_t *rs = zfs_btree_last(&rt->rt_root, NULL);
860 return (rs != NULL ? rs_get_end(rs, rt) : 0);
864 range_tree_span(range_tree_t *rt)
866 return (range_tree_max(rt) - range_tree_min(rt));