xref: /netbsd-src/sys/external/bsd/common/include/linux/list.h (revision 6a493d6bc668897c91594964a732d38505b70cbb)
1 /*	$NetBSD: list.h,v 1.1 2013/09/05 15:28:07 skrll Exp $	*/
2 
3 /*-
4  * Copyright (c) 2013 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Taylor R. Campbell.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #ifndef _LINUX_LIST_H_
33 #define _LINUX_LIST_H_
34 
35 #include <sys/null.h>
36 #include <sys/queue.h>
37 
38 #include <linux/kernel.h>
39 
40 /*
41  * Doubly-linked lists.
42  */
43 
44 struct list_head {
45 	struct list_head *prev;
46 	struct list_head *next;
47 };
48 
49 #define	LIST_HEAD_INIT(name)	{ .prev = &(name), .next = &(name) }
50 
51 static inline void
52 INIT_LIST_HEAD(struct list_head *head)
53 {
54 	head->prev = head;
55 	head->next = head;
56 }
57 
58 static inline struct list_head *
59 list_first(const struct list_head *head)
60 {
61 	return head->next;
62 }
63 
64 static inline struct list_head *
65 list_next(const struct list_head *node)
66 {
67 	return node->next;
68 }
69 
70 static inline struct list_head *
71 list_prev(const struct list_head *node)
72 {
73 	return node->prev;
74 }
75 
76 static inline int
77 list_empty(const struct list_head *head)
78 {
79 	return (head->next == head);
80 }
81 
82 static inline void
83 __list_add_between(struct list_head *prev, struct list_head *node,
84     struct list_head *next)
85 {
86 	prev->next = node;
87 	node->prev = prev;
88 	node->next = next;
89 	next->prev = node;
90 }
91 
92 static inline void
93 list_add(struct list_head *node, struct list_head *head)
94 {
95 	__list_add_between(head, node, head->next);
96 }
97 
98 static inline void
99 list_add_tail(struct list_head *node, struct list_head *head)
100 {
101 	__list_add_between(head->prev, node, head);
102 }
103 
104 static inline void
105 list_del(struct list_head *entry)
106 {
107 	entry->prev->next = entry->next;
108 	entry->next->prev = entry->prev;
109 }
110 
111 static inline void
112 __list_splice_between(struct list_head *prev, const struct list_head *list,
113     struct list_head *next)
114 {
115 	struct list_head *first = list->next;
116 	struct list_head *last = list->prev;
117 
118 	first->prev = prev;
119 	prev->next = first;
120 
121 	last->next = next;
122 	next->prev = last;
123 }
124 
125 static inline void
126 list_splice(const struct list_head *list, struct list_head *head)
127 {
128 	if (!list_empty(list))
129 		__list_splice_between(head, list, head->next);
130 }
131 
132 static inline void
133 list_splice_tail(const struct list_head *list, struct list_head *head)
134 {
135 	if (!list_empty(list))
136 		__list_splice_between(head->prev, list, head);
137 }
138 
139 static inline void
140 list_move(struct list_head *node, struct list_head *head)
141 {
142 	list_del(node);
143 	list_add(node, head);
144 }
145 
146 static inline void
147 list_move_tail(struct list_head *node, struct list_head *head)
148 {
149 	list_del(node);
150 	list_add_tail(node, head);
151 }
152 
153 static inline void
154 list_replace(struct list_head *old, struct list_head *new)
155 {
156 	new->prev = old->prev;
157 	old->prev->next = new;
158 	new->next = old->next;
159 	old->next->prev = new;
160 }
161 
162 static inline void
163 list_del_init(struct list_head *node)
164 {
165 	list_del(node);
166 	INIT_LIST_HEAD(node);
167 }
168 
169 #define	list_entry(PTR, TYPE, FIELD)	container_of(PTR, TYPE, FIELD)
170 #define	list_first_entry(PTR, TYPE, FIELD)				\
171 	list_entry(list_first((PTR)), TYPE, FIELD)
172 
173 #define	list_for_each(VAR, HEAD)					\
174 	for ((VAR) = list_first((HEAD));				\
175 		(VAR) != (HEAD);					\
176 		(VAR) = list_next((VAR)))
177 
178 #define	list_for_each_safe(VAR, NEXT, HEAD)				\
179 	for ((VAR) = list_first((HEAD));				\
180 		((VAR) != (HEAD)) && ((NEXT) = list_next((VAR)), 1);	\
181 		(VAR) = (NEXT))
182 
183 #define	list_for_each_entry(VAR, HEAD, FIELD)				\
184 	for ((VAR) = list_entry(list_first((HEAD)), typeof(*(VAR)), FIELD); \
185 		&(VAR)->FIELD != (HEAD);				\
186 		(VAR) = list_entry(list_next(&(VAR)->FIELD), typeof(*(VAR)), \
187 		    FIELD))
188 
189 #define	list_for_each_entry_safe(VAR, NEXT, HEAD, FIELD)		\
190 	for ((VAR) = list_entry(list_first((HEAD)), typeof(*(VAR)), FIELD); \
191 		(&(VAR)->FIELD != (HEAD)) &&				\
192 		    ((NEXT) = list_entry(list_next(&(VAR)->FIELD),	\
193 			typeof(*(VAR)), FIELD), 1);			\
194 		(VAR) = (NEXT))
195 
196 /*
197  * `H'ead-only/`H'ash-table doubly-linked lists.
198  */
199 
200 LIST_HEAD(hlist_head, hlist_node);
201 struct hlist_node {
202 	LIST_ENTRY(hlist_node) hln_entry;
203 };
204 
205 static inline struct hlist_node *
206 hlist_first(struct hlist_head *head)
207 {
208 	return LIST_FIRST(head);
209 }
210 
211 static inline struct hlist_node *
212 hlist_next(struct hlist_node *node)
213 {
214 	return LIST_NEXT(node, hln_entry);
215 }
216 
217 static inline void
218 hlist_add_head(struct hlist_node *node, struct hlist_head *head)
219 {
220 	LIST_INSERT_HEAD(head, node, hln_entry);
221 }
222 
223 static inline void
224 hlist_add_after(struct hlist_node *node, struct hlist_node *next)
225 {
226 	LIST_INSERT_AFTER(node, next, hln_entry);
227 }
228 
229 static inline void
230 hlist_del(struct hlist_node *node)
231 {
232 	LIST_REMOVE(node, hln_entry);
233 }
234 
235 static inline void
236 hlist_del_init(struct hlist_node *node)
237 {
238 	LIST_REMOVE(node, hln_entry);
239 }
240 
241 #define	hlist_entry(PTR, TYPE, FIELD)	container_of(PTR, TYPE, FIELD)
242 #define	hlist_for_each(VAR, HEAD)	LIST_FOREACH(VAR, HEAD, hln_entry)
243 #define	hlist_for_each_safe(VAR, NEXT, HEAD)				\
244 	LIST_FOREACH_SAFE(VAR, HEAD, hln_entry, NEXT)
245 
246 #define	hlist_for_each_entry(VAR, HLIST, HEAD, FIELD)			\
247 	for ((HLIST) = LIST_FIRST((HEAD));				\
248 		((HLIST) != NULL) &&					\
249 		    ((VAR) = hlist_entry((HLIST), typeof(*(VAR)), FIELD), 1); \
250 		(HLIST) = LIST_NEXT((HLIST), hln_entry))
251 
252 /*
253  * XXX The nominally RCU-safe APIs below lack dependent read barriers,
254  * so they're not actually RCU-safe...on the alpha, anyway.  Someone^TM
255  * should fix this.
256  */
257 
258 #define	hlist_add_after_rcu		hlist_add_after
259 #define	hlist_add_head_rcu		hlist_add_head
260 #define	hlist_del_init_rcu		hlist_del_init
261 #define	hlist_for_each_entry_rcu	hlist_for_each_entry
262 
263 #endif  /* _LINUX_LIST_H_ */
264