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 <sys/tree.h>
33
34 struct rb_node {
35 RB_ENTRY(rb_node) __entry;
36 };
37 #define rb_left __entry.rbe_left
38 #define rb_right __entry.rbe_right
39
40 /*
41 * We provide a false structure that has the same bit pattern as tree.h
42 * presents so it matches the member names expected by linux.
43 */
44 struct rb_root {
45 struct rb_node *rb_node;
46 };
47
48 struct rb_root_cached {
49 struct rb_root rb_root;
50 };
51
52 /*
53 * In linux all of the comparisons are done by the caller.
54 */
55 int panic_cmp(struct rb_node *one, struct rb_node *two);
56
57 RB_HEAD(linux_root, rb_node);
58 RB_PROTOTYPE(linux_root, rb_node, __entry, panic_cmp);
59
60 #define rb_parent(r) RB_PARENT(r, __entry)
61 #define rb_color(r) RB_COLOR(r, __entry)
62 #define rb_is_red(r) (rb_color(r) == RB_RED)
63 #define rb_is_black(r) (rb_color(r) == RB_BLACK)
64 #define rb_set_parent(r, p) rb_parent((r)) = (p)
65 #define rb_set_color(r, c) rb_color((r)) = (c)
66 #define rb_entry(ptr, type, member) container_of(ptr, type, member)
67 #define rb_entry_safe(ptr, type, member) \
68 (ptr ? rb_entry(ptr, type, member) : NULL)
69
70 #define RB_EMPTY_ROOT(root) ((root)->rb_node == NULL)
71 #define RB_EMPTY_NODE(node) (rb_parent(node) == node)
72 #define RB_CLEAR_NODE(node) (rb_set_parent(node, node))
73
74 #define rb_insert_color(node, root) \
75 linux_root_RB_INSERT_COLOR((struct linux_root *)(root), (node))
76 #define rb_erase(node, root) \
77 linux_root_RB_REMOVE((struct linux_root *)(root), (node))
78 #define rb_next(node) RB_NEXT(linux_root, NULL, (node))
79 #define rb_prev(node) RB_PREV(linux_root, NULL, (node))
80 #define rb_first(root) RB_MIN(linux_root, (struct linux_root *)(root))
81 #define rb_last(root) RB_MAX(linux_root, (struct linux_root *)(root))
82
83 #define rb_insert_color_cached(node, root, leftmost) \
84 linux_root_RB_INSERT_COLOR((struct linux_root *)(&(root)->rb_root), (node))
85 #define rb_erase_cached(node, root) \
86 linux_root_RB_REMOVE((struct linux_root *)(&(root)->rb_root), (node))
87 #define rb_first_cached(root) RB_MIN(linux_root, (struct linux_root *)(&(root)->rb_root))
88 #define rb_replace_node_cached(old, new, root) \
89 rb_replace_node(old, new, &(root)->rb_root)
90
91 static inline struct rb_node *
__rb_deepest_left(struct rb_node * node)92 __rb_deepest_left(struct rb_node *node)
93 {
94 struct rb_node *parent = NULL;
95 while (node) {
96 parent = node;
97 if (RB_LEFT(node, __entry))
98 node = RB_LEFT(node, __entry);
99 else
100 node = RB_RIGHT(node, __entry);
101 }
102 return parent;
103 }
104
105 static inline struct rb_node *
rb_next_postorder(const struct rb_node * node)106 rb_next_postorder(const struct rb_node *node)
107 {
108 struct rb_node *parent = RB_PARENT(node, __entry);
109 /* left -> right, right -> root */
110 if (parent != NULL &&
111 (node == RB_LEFT(parent, __entry)) &&
112 (RB_RIGHT(parent, __entry)))
113 return __rb_deepest_left(RB_RIGHT(parent, __entry));
114 else
115 return parent;
116 }
117
118 #define rbtree_postorder_for_each_entry_safe(x, y, head, member) \
119 for ((x) = rb_entry_safe(__rb_deepest_left((head)->rb_node), \
120 __typeof(*x), member); \
121 ((x) != NULL) && ((y) = \
122 rb_entry_safe(rb_next_postorder(&x->member), typeof(*x), member), 1); \
123 (x) = (y))
124
125 static inline void
rb_link_node(struct rb_node * node,struct rb_node * parent,struct rb_node ** rb_link)126 rb_link_node(struct rb_node *node, struct rb_node *parent,
127 struct rb_node **rb_link)
128 {
129 rb_set_parent(node, parent);
130 rb_set_color(node, RB_RED);
131 node->__entry.rbe_left = node->__entry.rbe_right = NULL;
132 *rb_link = node;
133 }
134
135 static inline void
rb_replace_node(struct rb_node * victim,struct rb_node * new,struct rb_root * root)136 rb_replace_node(struct rb_node *victim, struct rb_node *new,
137 struct rb_root *root)
138 {
139 struct rb_node *p;
140
141 p = rb_parent(victim);
142 if (p) {
143 if (p->rb_left == victim)
144 p->rb_left = new;
145 else
146 p->rb_right = new;
147 } else
148 root->rb_node = new;
149 if (victim->rb_left)
150 rb_set_parent(victim->rb_left, new);
151 if (victim->rb_right)
152 rb_set_parent(victim->rb_right, new);
153 *new = *victim;
154 }
155
156 static inline void
rb_add_cached(struct rb_node * node,struct rb_root_cached * root,bool (* less)(struct rb_node *,const struct rb_node *))157 rb_add_cached(struct rb_node *node, struct rb_root_cached *root,
158 bool (*less)(struct rb_node *, const struct rb_node *))
159 {
160 struct rb_node **iter = &root->rb_root.rb_node;
161 struct rb_node *parent = NULL;
162
163 while (*iter) {
164 parent = *iter;
165
166 if (less(node, parent))
167 iter = &(*iter)->rb_left;
168 else
169 iter = &(*iter)->rb_right;
170 }
171
172 rb_link_node(node, parent, iter);
173 rb_insert_color_cached(node, root, false);
174 }
175
176 #undef RB_ROOT
177 #define RB_ROOT (struct rb_root) { NULL }
178 #ifdef __clang__
179 #define RB_ROOT_CACHED (struct rb_root_cached) { NULL }
180 #else
181 #define RB_ROOT_CACHED (struct rb_root_cached) { { NULL } }
182 #endif
183
184 #endif /* _LINUX_RBTREE_H_ */
185