include/sys/range_tree.h

   1 /*
   2  * CDDL HEADER START
   3  *
   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.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  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]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25
  26 /*
  27  * Copyright (c) 2013, 2017 by Delphix. All rights reserved.
  28  */
  29
  30 #ifndef _SYS_RANGE_TREE_H
  31 #define _SYS_RANGE_TREE_H
  32
  33 #include <sys/avl.h>
  34 #include <sys/dmu.h>
  35
  36 #ifdef  __cplusplus
  37 extern "C" {
  38 #endif
  39
  40 #define RANGE_TREE_HISTOGRAM_SIZE       64
  41
  42 typedef struct range_tree_ops range_tree_ops_t;
  43
  44 /*
  45  * Note: the range_tree may not be accessed concurrently; consumers
  46  * must provide external locking if required.
  47  */
  48 typedef struct range_tree {
  49         avl_tree_t      rt_root;        /* offset-ordered segment AVL tree */
  50         uint64_t        rt_space;       /* sum of all segments in the map */
  51         uint64_t        rt_gap;         /* allowable inter-segment gap */
  52         range_tree_ops_t *rt_ops;
  53
  54         /* rt_avl_compare should only be set if rt_arg is an AVL tree */
  55         void            *rt_arg;
  56         int (*rt_avl_compare)(const void *, const void *);
  57
  58
  59         /*
  60          * The rt_histogram maintains a histogram of ranges. Each bucket,
  61          * rt_histogram[i], contains the number of ranges whose size is:
  62          * 2^i <= size of range in bytes < 2^(i+1)
  63          */
  64         uint64_t        rt_histogram[RANGE_TREE_HISTOGRAM_SIZE];
  65 } range_tree_t;
  66
  67 typedef struct range_seg {
  68         avl_node_t      rs_node;        /* AVL node */
  69         avl_node_t      rs_pp_node;     /* AVL picker-private node */
  70         uint64_t        rs_start;       /* starting offset of this segment */
  71         uint64_t        rs_end;         /* ending offset (non-inclusive) */
  72         uint64_t        rs_fill;        /* actual fill if gap mode is on */
  73 } range_seg_t;
  74
  75 struct range_tree_ops {
  76         void    (*rtop_create)(range_tree_t *rt, void *arg);
  77         void    (*rtop_destroy)(range_tree_t *rt, void *arg);
  78         void    (*rtop_add)(range_tree_t *rt, range_seg_t *rs, void *arg);
  79         void    (*rtop_remove)(range_tree_t *rt, range_seg_t *rs, void *arg);
  80         void    (*rtop_vacate)(range_tree_t *rt, void *arg);
  81 };
  82
  83 typedef void range_tree_func_t(void *arg, uint64_t start, uint64_t size);
  84
  85 void range_tree_init(void);
  86 void range_tree_fini(void);
  87 range_tree_t *range_tree_create_impl(range_tree_ops_t *ops, void *arg,
  88     int (*avl_compare) (const void *, const void *), uint64_t gap);
  89 range_tree_t *range_tree_create(range_tree_ops_t *ops, void *arg);
  90 void range_tree_destroy(range_tree_t *rt);
  91 boolean_t range_tree_contains(range_tree_t *rt, uint64_t start, uint64_t size);
  92 void range_tree_verify_not_present(range_tree_t *rt,
  93     uint64_t start, uint64_t size);
  94 range_seg_t *range_tree_find(range_tree_t *rt, uint64_t start, uint64_t size);
  95 void range_tree_resize_segment(range_tree_t *rt, range_seg_t *rs,
  96     uint64_t newstart, uint64_t newsize);
  97 uint64_t range_tree_space(range_tree_t *rt);
  98 boolean_t range_tree_is_empty(range_tree_t *rt);
  99 void range_tree_swap(range_tree_t **rtsrc, range_tree_t **rtdst);
 100 void range_tree_stat_verify(range_tree_t *rt);
 101 uint64_t range_tree_min(range_tree_t *rt);
 102 uint64_t range_tree_max(range_tree_t *rt);
 103 uint64_t range_tree_span(range_tree_t *rt);
 104
 105 void range_tree_add(void *arg, uint64_t start, uint64_t size);
 106 void range_tree_remove(void *arg, uint64_t start, uint64_t size);
 107 void range_tree_remove_fill(range_tree_t *rt, uint64_t start, uint64_t size);
 108 void range_tree_adjust_fill(range_tree_t *rt, range_seg_t *rs, int64_t delta);
 109 void range_tree_clear(range_tree_t *rt, uint64_t start, uint64_t size);
 110
 111 void range_tree_vacate(range_tree_t *rt, range_tree_func_t *func, void *arg);
 112 void range_tree_walk(range_tree_t *rt, range_tree_func_t *func, void *arg);
 113 range_seg_t *range_tree_first(range_tree_t *rt);
 114
 115 void rt_avl_create(range_tree_t *rt, void *arg);
 116 void rt_avl_destroy(range_tree_t *rt, void *arg);
 117 void rt_avl_add(range_tree_t *rt, range_seg_t *rs, void *arg);
 118 void rt_avl_remove(range_tree_t *rt, range_seg_t *rs, void *arg);
 119 void rt_avl_vacate(range_tree_t *rt, void *arg);
 120 extern struct range_tree_ops rt_avl_ops;
 121
 122 #ifdef  __cplusplus
 123 }
 124 #endif
 125
 126 #endif  /* _SYS_RANGE_TREE_H */