1 /*- 2 * Copyright (c) 2010 Isilon Systems, Inc. 3 * Copyright (c) 2010 iX Systems, Inc. 4 * Copyright (c) 2010 Panasas, Inc. 5 * Copyright (c) 2013, 2014 Mellanox Technologies, Ltd. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice unmodified, this list of conditions, and the following 13 * disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 */ 29 #ifndef _LINUX_RBTREE_H_ 30 #define _LINUX_RBTREE_H_ 31 32 #include <linux/kernel.h> 33 #include <linux/stddef.h> 34 #include <linux/rcupdate.h> 35 36 #include <sys/tree.h> 37 #include <sys/spinlock.h> 38 39 struct rb_node { 40 RB_ENTRY(rb_node) __entry; 41 }; 42 #define rb_left __entry.rbe_left 43 #define rb_right __entry.rbe_right 44 45 /* 46 * This must match enough of sys/tree.h so the macros still work. 47 */ 48 struct rb_root { 49 struct rb_node *rb_node; /* only member under linux */ 50 void *rbh_inprog; /* so we can use sys/tree macros */ 51 struct spinlock rbh_spin; /* so we can use sys/tree macros */ 52 }; 53 54 /* 55 * Leftmost-cached rbtrees. 56 * 57 * We do not cache the rightmost node based on footprint 58 * size vs number of potential users that could benefit 59 * from O(1) rb_last(). Just not worth it, users that want 60 * this feature can always implement the logic explicitly. 61 * Furthermore, users that want to cache both pointers may 62 * find it a bit asymmetric, but that's ok. 63 */ 64 struct rb_root_cached { 65 struct rb_root rb_root; 66 struct rb_node *rb_leftmost; 67 }; 68 69 /* 70 * In linux all of the comparisons are done by the caller. 71 */ 72 int panic_cmp(struct rb_node *one, struct rb_node *two); 73 74 RB_HEAD(linux_root, rb_node); 75 RB_PROTOTYPE(linux_root, rb_node, __entry, panic_cmp); 76 77 #define rb_parent(r) RB_PARENT(r, __entry) 78 #define rb_color(r) RB_COLOR(r, __entry) 79 #define rb_is_red(r) (rb_color(r) == RB_RED) 80 #define rb_is_black(r) (rb_color(r) == RB_BLACK) 81 #define rb_set_parent(r, p) rb_parent((r)) = (p) 82 #define rb_set_color(r, c) rb_color((r)) = (c) 83 #define rb_entry(ptr, type, member) container_of(ptr, type, member) 84 #define rb_entry_safe(ptr, type, member) \ 85 (ptr ? rb_entry(ptr, type, member) : NULL) 86 87 #define RB_EMPTY_ROOT(root) RB_EMPTY((struct linux_root *)root) 88 #define RB_EMPTY_NODE(node) (rb_parent(node) == node) 89 #define RB_CLEAR_NODE(node) (rb_set_parent(node, node)) 90 91 #define rb_insert_color(node, root) \ 92 linux_root_RB_INSERT_COLOR((struct linux_root *)(root), (node)) 93 #define rb_erase(node, root) \ 94 linux_root_RB_REMOVE((struct linux_root *)(root), (node)) 95 #define rb_next(node) RB_NEXT(linux_root, NULL, (node)) 96 #define rb_prev(node) RB_PREV(linux_root, NULL, (node)) 97 #define rb_first(root) RB_MIN(linux_root, (struct linux_root *)(root)) 98 #define rb_last(root) RB_MAX(linux_root, (struct linux_root *)(root)) 99 100 #define rb_insert_color_cached(node, root, leftmost) \ 101 linux_root_RB_INSERT_COLOR((struct linux_root *)(&(root)->rb_root), (node)) 102 #define rb_erase_cached(node, root) \ 103 linux_root_RB_REMOVE((struct linux_root *)(&(root)->rb_root), (node)) 104 #define rb_first_cached(root) RB_MIN(linux_root, (struct linux_root *)(&(root)->rb_root)) 105 106 static inline struct rb_node * 107 __rb_deepest_left(struct rb_node *node) 108 { 109 struct rb_node *parent = NULL; 110 while (node) { 111 parent = node; 112 if (RB_LEFT(node, __entry)) 113 node = RB_LEFT(node, __entry); 114 else 115 node = RB_RIGHT(node, __entry); 116 } 117 return parent; 118 } 119 120 static inline struct rb_node * 121 rb_next_postorder(const struct rb_node *node) 122 { 123 struct rb_node *parent = RB_PARENT(node, __entry); 124 /* left -> right, right -> root */ 125 if (parent != NULL && 126 (node == RB_LEFT(parent, __entry)) && 127 (RB_RIGHT(parent, __entry))) 128 return __rb_deepest_left(RB_RIGHT(parent, __entry)); 129 else 130 return parent; 131 } 132 133 #define rbtree_postorder_for_each_entry_safe(x, y, head, member) \ 134 for ((x) = rb_entry_safe(__rb_deepest_left((head)->rb_node), \ 135 __typeof(*x), member); \ 136 ((x) != NULL) && ((y) = \ 137 rb_entry_safe(rb_next_postorder(&x->member), typeof(*x), member), 1); \ 138 (x) = (y)) 139 140 static inline void 141 rb_link_node(struct rb_node *node, struct rb_node *parent, 142 struct rb_node **rb_link) 143 { 144 rb_set_parent(node, parent); 145 rb_set_color(node, RB_RED); 146 node->__entry.rbe_left = node->__entry.rbe_right = NULL; 147 *rb_link = node; 148 } 149 150 static inline void 151 rb_replace_node(struct rb_node *victim, struct rb_node *new, 152 struct rb_root *root) 153 { 154 struct rb_node *p; 155 156 p = rb_parent(victim); 157 if (p) { 158 if (p->rb_left == victim) 159 p->rb_left = new; 160 else 161 p->rb_right = new; 162 } else 163 root->rb_node = new; 164 if (victim->rb_left) 165 rb_set_parent(victim->rb_left, new); 166 if (victim->rb_right) 167 rb_set_parent(victim->rb_right, new); 168 *new = *victim; 169 } 170 171 #define LINUX_RB_ROOT (struct rb_root) { NULL } 172 173 #define LINUX_RB_ROOT_CACHED (struct rb_root_cached) { {NULL, }, NULL } 174 175 #endif /* _LINUX_RBTREE_H_ */ 176