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, 2019 by Delphix. All rights reserved.
  28  */
  29
  30 #ifndef _SYS_RANGE_TREE_H
  31 #define _SYS_RANGE_TREE_H
  32
  33 #include <sys/btree.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 typedef enum range_seg_type {
  45         RANGE_SEG32,
  46         RANGE_SEG64,
  47         RANGE_SEG_GAP,
  48         RANGE_SEG_NUM_TYPES,
  49 } range_seg_type_t;
  50
  51 /*
  52  * Note: the range_tree may not be accessed concurrently; consumers
  53  * must provide external locking if required.
  54  */
  55 typedef struct range_tree {
  56         zfs_btree_t     rt_root;        /* offset-ordered segment b-tree */
  57         uint64_t        rt_space;       /* sum of all segments in the map */
  58         range_seg_type_t rt_type;       /* type of range_seg_t in use */
  59         /*
  60          * All data that is stored in the range tree must have a start higher
  61          * than or equal to rt_start, and all sizes and offsets must be
  62          * multiples of 1 << rt_shift.
  63          */
  64         uint8_t         rt_shift;
  65         uint64_t        rt_start;
  66         const range_tree_ops_t *rt_ops;
  67
  68         /* rt_btree_compare should only be set if rt_arg is a b-tree */
  69         void            *rt_arg;
  70         int (*rt_btree_compare)(const void *, const void *);
  71
  72         uint64_t        rt_gap;         /* allowable inter-segment gap */
  73
  74         /*
  75          * The rt_histogram maintains a histogram of ranges. Each bucket,
  76          * rt_histogram[i], contains the number of ranges whose size is:
  77          * 2^i <= size of range in bytes < 2^(i+1)
  78          */
  79         uint64_t        rt_histogram[RANGE_TREE_HISTOGRAM_SIZE];
  80 } range_tree_t;
  81
  82 typedef struct range_seg32 {
  83         uint32_t        rs_start;       /* starting offset of this segment */
  84         uint32_t        rs_end;         /* ending offset (non-inclusive) */
  85 } range_seg32_t;
  86
  87 /*
  88  * Extremely large metaslabs, vdev-wide trees, and dnode-wide trees may
  89  * require 64-bit integers for ranges.
  90  */
  91 typedef struct range_seg64 {
  92         uint64_t        rs_start;       /* starting offset of this segment */
  93         uint64_t        rs_end;         /* ending offset (non-inclusive) */
  94 } range_seg64_t;
  95
  96 typedef struct range_seg_gap {
  97         uint64_t        rs_start;       /* starting offset of this segment */
  98         uint64_t        rs_end;         /* ending offset (non-inclusive) */
  99         uint64_t        rs_fill;        /* actual fill if gap mode is on */
 100 } range_seg_gap_t;
 101
 102 /*
 103  * This type needs to be the largest of the range segs, since it will be stack
 104  * allocated and then cast the actual type to do tree operations.
 105  */
 106 typedef range_seg_gap_t range_seg_max_t;
 107
 108 /*
 109  * This is just for clarity of code purposes, so we can make it clear that a
 110  * pointer is to a range seg of some type; when we need to do the actual math,
 111  * we'll figure out the real type.
 112  */
 113 typedef void range_seg_t;
 114
 115 struct range_tree_ops {
 116         void    (*rtop_create)(range_tree_t *rt, void *arg);
 117         void    (*rtop_destroy)(range_tree_t *rt, void *arg);
 118         void    (*rtop_add)(range_tree_t *rt, void *rs, void *arg);
 119         void    (*rtop_remove)(range_tree_t *rt, void *rs, void *arg);
 120         void    (*rtop_vacate)(range_tree_t *rt, void *arg);
 121 };
 122
 123 static inline uint64_t
 124 rs_get_start_raw(const range_seg_t *rs, const range_tree_t *rt)
 125 {
 126         ASSERT3U(rt->rt_type, <=, RANGE_SEG_NUM_TYPES);
 127         switch (rt->rt_type) {
 128         case RANGE_SEG32:
 129                 return (((const range_seg32_t *)rs)->rs_start);
 130         case RANGE_SEG64:
 131                 return (((const range_seg64_t *)rs)->rs_start);
 132         case RANGE_SEG_GAP:
 133                 return (((const range_seg_gap_t *)rs)->rs_start);
 134         default:
 135                 VERIFY(0);
 136                 return (0);
 137         }
 138 }
 139
 140 static inline uint64_t
 141 rs_get_end_raw(const range_seg_t *rs, const range_tree_t *rt)
 142 {
 143         ASSERT3U(rt->rt_type, <=, RANGE_SEG_NUM_TYPES);
 144         switch (rt->rt_type) {
 145         case RANGE_SEG32:
 146                 return (((const range_seg32_t *)rs)->rs_end);
 147         case RANGE_SEG64:
 148                 return (((const range_seg64_t *)rs)->rs_end);
 149         case RANGE_SEG_GAP:
 150                 return (((const range_seg_gap_t *)rs)->rs_end);
 151         default:
 152                 VERIFY(0);
 153                 return (0);
 154         }
 155 }
 156
 157 static inline uint64_t
 158 rs_get_fill_raw(const range_seg_t *rs, const range_tree_t *rt)
 159 {
 160         ASSERT3U(rt->rt_type, <=, RANGE_SEG_NUM_TYPES);
 161         switch (rt->rt_type) {
 162         case RANGE_SEG32: {
 163                 const range_seg32_t *r32 = (const range_seg32_t *)rs;
 164                 return (r32->rs_end - r32->rs_start);
 165         }
 166         case RANGE_SEG64: {
 167                 const range_seg64_t *r64 = (const range_seg64_t *)rs;
 168                 return (r64->rs_end - r64->rs_start);
 169         }
 170         case RANGE_SEG_GAP:
 171                 return (((const range_seg_gap_t *)rs)->rs_fill);
 172         default:
 173                 VERIFY(0);
 174                 return (0);
 175         }
 176
 177 }
 178
 179 static inline uint64_t
 180 rs_get_start(const range_seg_t *rs, const range_tree_t *rt)
 181 {
 182         return ((rs_get_start_raw(rs, rt) << rt->rt_shift) + rt->rt_start);
 183 }
 184
 185 static inline uint64_t
 186 rs_get_end(const range_seg_t *rs, const range_tree_t *rt)
 187 {
 188         return ((rs_get_end_raw(rs, rt) << rt->rt_shift) + rt->rt_start);
 189 }
 190
 191 static inline uint64_t
 192 rs_get_fill(const range_seg_t *rs, const range_tree_t *rt)
 193 {
 194         return (rs_get_fill_raw(rs, rt) << rt->rt_shift);
 195 }
 196
 197 static inline void
 198 rs_set_start_raw(range_seg_t *rs, range_tree_t *rt, uint64_t start)
 199 {
 200         ASSERT3U(rt->rt_type, <=, RANGE_SEG_NUM_TYPES);
 201         switch (rt->rt_type) {
 202         case RANGE_SEG32:
 203                 ASSERT3U(start, <=, UINT32_MAX);
 204                 ((range_seg32_t *)rs)->rs_start = (uint32_t)start;
 205                 break;
 206         case RANGE_SEG64:
 207                 ((range_seg64_t *)rs)->rs_start = start;
 208                 break;
 209         case RANGE_SEG_GAP:
 210                 ((range_seg_gap_t *)rs)->rs_start = start;
 211                 break;
 212         default:
 213                 VERIFY(0);
 214         }
 215 }
 216
 217 static inline void
 218 rs_set_end_raw(range_seg_t *rs, range_tree_t *rt, uint64_t end)
 219 {
 220         ASSERT3U(rt->rt_type, <=, RANGE_SEG_NUM_TYPES);
 221         switch (rt->rt_type) {
 222         case RANGE_SEG32:
 223                 ASSERT3U(end, <=, UINT32_MAX);
 224                 ((range_seg32_t *)rs)->rs_end = (uint32_t)end;
 225                 break;
 226         case RANGE_SEG64:
 227                 ((range_seg64_t *)rs)->rs_end = end;
 228                 break;
 229         case RANGE_SEG_GAP:
 230                 ((range_seg_gap_t *)rs)->rs_end = end;
 231                 break;
 232         default:
 233                 VERIFY(0);
 234         }
 235 }
 236
 237 static inline void
 238 rs_set_fill_raw(range_seg_t *rs, range_tree_t *rt, uint64_t fill)
 239 {
 240         ASSERT3U(rt->rt_type, <=, RANGE_SEG_NUM_TYPES);
 241         switch (rt->rt_type) {
 242         case RANGE_SEG32:
 243                 /* fall through */
 244         case RANGE_SEG64:
 245                 ASSERT3U(fill, ==, rs_get_end_raw(rs, rt) - rs_get_start_raw(rs,
 246                     rt));
 247                 break;
 248         case RANGE_SEG_GAP:
 249                 ((range_seg_gap_t *)rs)->rs_fill = fill;
 250                 break;
 251         default:
 252                 VERIFY(0);
 253         }
 254 }
 255
 256 static inline void
 257 rs_set_start(range_seg_t *rs, range_tree_t *rt, uint64_t start)
 258 {
 259         ASSERT3U(start, >=, rt->rt_start);
 260         ASSERT(IS_P2ALIGNED(start, 1ULL << rt->rt_shift));
 261         rs_set_start_raw(rs, rt, (start - rt->rt_start) >> rt->rt_shift);
 262 }
 263
 264 static inline void
 265 rs_set_end(range_seg_t *rs, range_tree_t *rt, uint64_t end)
 266 {
 267         ASSERT3U(end, >=, rt->rt_start);
 268         ASSERT(IS_P2ALIGNED(end, 1ULL << rt->rt_shift));
 269         rs_set_end_raw(rs, rt, (end - rt->rt_start) >> rt->rt_shift);
 270 }
 271
 272 static inline void
 273 rs_set_fill(range_seg_t *rs, range_tree_t *rt, uint64_t fill)
 274 {
 275         ASSERT(IS_P2ALIGNED(fill, 1ULL << rt->rt_shift));
 276         rs_set_fill_raw(rs, rt, fill >> rt->rt_shift);
 277 }
 278
 279 typedef void range_tree_func_t(void *arg, uint64_t start, uint64_t size);
 280
 281 range_tree_t *range_tree_create_impl(const range_tree_ops_t *ops,
 282     range_seg_type_t type, void *arg, uint64_t start, uint64_t shift,
 283     int (*zfs_btree_compare) (const void *, const void *), uint64_t gap);
 284 range_tree_t *range_tree_create(const range_tree_ops_t *ops,
 285     range_seg_type_t type, void *arg, uint64_t start, uint64_t shift);
 286 void range_tree_destroy(range_tree_t *rt);
 287 boolean_t range_tree_contains(range_tree_t *rt, uint64_t start, uint64_t size);
 288 range_seg_t *range_tree_find(range_tree_t *rt, uint64_t start, uint64_t size);
 289 boolean_t range_tree_find_in(range_tree_t *rt, uint64_t start, uint64_t size,
 290     uint64_t *ostart, uint64_t *osize);
 291 void range_tree_verify_not_present(range_tree_t *rt,
 292     uint64_t start, uint64_t size);
 293 void range_tree_resize_segment(range_tree_t *rt, range_seg_t *rs,
 294     uint64_t newstart, uint64_t newsize);
 295 uint64_t range_tree_space(range_tree_t *rt);
 296 uint64_t range_tree_numsegs(range_tree_t *rt);
 297 boolean_t range_tree_is_empty(range_tree_t *rt);
 298 void range_tree_swap(range_tree_t **rtsrc, range_tree_t **rtdst);
 299 void range_tree_stat_verify(range_tree_t *rt);
 300 uint64_t range_tree_min(range_tree_t *rt);
 301 uint64_t range_tree_max(range_tree_t *rt);
 302 uint64_t range_tree_span(range_tree_t *rt);
 303
 304 void range_tree_add(void *arg, uint64_t start, uint64_t size);
 305 void range_tree_remove(void *arg, uint64_t start, uint64_t size);
 306 void range_tree_remove_fill(range_tree_t *rt, uint64_t start, uint64_t size);
 307 void range_tree_adjust_fill(range_tree_t *rt, range_seg_t *rs, int64_t delta);
 308 void range_tree_clear(range_tree_t *rt, uint64_t start, uint64_t size);
 309
 310 void range_tree_vacate(range_tree_t *rt, range_tree_func_t *func, void *arg);
 311 void range_tree_walk(range_tree_t *rt, range_tree_func_t *func, void *arg);
 312 range_seg_t *range_tree_first(range_tree_t *rt);
 313
 314 void range_tree_remove_xor_add_segment(uint64_t start, uint64_t end,
 315     range_tree_t *removefrom, range_tree_t *addto);
 316 void range_tree_remove_xor_add(range_tree_t *rt, range_tree_t *removefrom,
 317     range_tree_t *addto);
 318
 319 void rt_btree_create(range_tree_t *rt, void *arg);
 320 void rt_btree_destroy(range_tree_t *rt, void *arg);
 321 void rt_btree_add(range_tree_t *rt, range_seg_t *rs, void *arg);
 322 void rt_btree_remove(range_tree_t *rt, range_seg_t *rs, void *arg);
 323 void rt_btree_vacate(range_tree_t *rt, void *arg);
 324 extern const range_tree_ops_t rt_btree_ops;
 325
 326 #ifdef  __cplusplus
 327 }
 328 #endif
 329
 330 #endif  /* _SYS_RANGE_TREE_H */