xref: /dragonfly/sys/dev/drm/include/linux/rbtree.h (revision da0d35cf)
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  * In linux all of the comparisons are done by the caller.
56  */
57 int panic_cmp(struct rb_node *one, struct rb_node *two);
58 
59 RB_HEAD(linux_root, rb_node);
60 RB_PROTOTYPE(linux_root, rb_node, __entry, panic_cmp);
61 
62 #define	rb_parent(r)	RB_PARENT(r, __entry)
63 #define	rb_color(r)	RB_COLOR(r, __entry)
64 #define	rb_is_red(r)	(rb_color(r) == RB_RED)
65 #define	rb_is_black(r)	(rb_color(r) == RB_BLACK)
66 #define	rb_set_parent(r, p)	rb_parent((r)) = (p)
67 #define	rb_set_color(r, c)	rb_color((r)) = (c)
68 #define	rb_entry(ptr, type, member)	container_of(ptr, type, member)
69 #define	rb_entry_safe(ptr, type, member) \
70 	(ptr ? rb_entry(ptr, type, member) : NULL)
71 
72 #define RB_EMPTY_ROOT(root)     RB_EMPTY((struct linux_root *)root)
73 #define RB_EMPTY_NODE(node)     (rb_parent(node) == node)
74 #define RB_CLEAR_NODE(node)     (rb_set_parent(node, node))
75 
76 #define	rb_insert_color(node, root)					\
77 	linux_root_RB_INSERT_COLOR((struct linux_root *)(root), (node))
78 #define	rb_erase(node, root)						\
79 	linux_root_RB_REMOVE((struct linux_root *)(root), (node))
80 #define	rb_next(node)	RB_NEXT(linux_root, NULL, (node))
81 #define	rb_prev(node)	RB_PREV(linux_root, NULL, (node))
82 #define	rb_first(root)	RB_MIN(linux_root, (struct linux_root *)(root))
83 #define	rb_last(root)	RB_MAX(linux_root, (struct linux_root *)(root))
84 
85 static inline struct rb_node *
86 __rb_deepest_left(struct rb_node *node)
87 {
88 	struct rb_node *parent = NULL;
89 	while (node) {
90 		parent = node;
91 		if (RB_LEFT(node, __entry))
92 			node = RB_LEFT(node, __entry);
93 		else
94 			node = RB_RIGHT(node, __entry);
95 	}
96 	return parent;
97 }
98 
99 static inline struct rb_node *
100 rb_next_postorder(const struct rb_node *node)
101 {
102 	struct rb_node *parent = RB_PARENT(node, __entry);
103 	/* left -> right, right -> root */
104 	if (parent != NULL &&
105 	    (node == RB_LEFT(parent, __entry)) &&
106 	    (RB_RIGHT(parent, __entry)))
107 		return __rb_deepest_left(RB_RIGHT(parent, __entry));
108 	else
109 		return parent;
110 }
111 
112 #define	rbtree_postorder_for_each_entry_safe(x, y, head, member)	\
113 	for ((x) = rb_entry_safe(__rb_deepest_left((head)->rb_node),	\
114 	    __typeof(*x), member);					\
115 	    ((x) != NULL) && ((y) =					\
116 	    rb_entry_safe(rb_next_postorder(&x->member), typeof(*x), member), 1); \
117 	    (x) = (y))
118 
119 static inline void
120 rb_link_node(struct rb_node *node, struct rb_node *parent,
121     struct rb_node **rb_link)
122 {
123 	rb_set_parent(node, parent);
124 	rb_set_color(node, RB_RED);
125 	node->__entry.rbe_left = node->__entry.rbe_right = NULL;
126 	*rb_link = node;
127 }
128 
129 static inline void
130 rb_replace_node(struct rb_node *victim, struct rb_node *new,
131     struct rb_root *root)
132 {
133 	struct rb_node *p;
134 
135 	p = rb_parent(victim);
136 	if (p) {
137 		if (p->rb_left == victim)
138 			p->rb_left = new;
139 		else
140 			p->rb_right = new;
141 	} else
142 		root->rb_node = new;
143 	if (victim->rb_left)
144 		rb_set_parent(victim->rb_left, new);
145 	if (victim->rb_right)
146 		rb_set_parent(victim->rb_right, new);
147 	*new = *victim;
148 }
149 
150 #define LINUX_RB_ROOT		(struct rb_root) { NULL }
151 
152 #endif	/* _LINUX_RBTREE_H_ */
153