xref: /freebsd/sys/compat/linuxkpi/common/include/linux/rculist.h (revision f976241773df2260e6170317080761d1c5814fe5)
1 /*-
2  * Copyright (c) 2015 François Tigeot
3  * Copyright (c) 2016-2017 Mellanox Technologies, Ltd.
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice unmodified, this list of conditions, and the following
11  *    disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  *
27  * $FreeBSD$
28  */
29 
30 #ifndef _LINUX_RCULIST_H_
31 #define	_LINUX_RCULIST_H_
32 
33 #include <linux/list.h>
34 #include <linux/rcupdate.h>
35 
36 #define	list_entry_rcu(ptr, type, member) \
37 	container_of(READ_ONCE(ptr), type, member)
38 
39 #define	list_next_rcu(head)	(*((struct list_head **)(&(head)->next)))
40 
41 #define	list_for_each_entry_rcu(pos, head, member) \
42 	for (pos = list_entry_rcu((head)->next, typeof(*(pos)), member); \
43 	     &(pos)->member != (head);					\
44 	     pos = list_entry_rcu((pos)->member.next, typeof(*(pos)), member))
45 
46 static inline void
47 list_add_rcu(struct list_head *new, struct list_head *prev)
48 {
49 	new->next = prev->next;
50 	new->prev = prev;
51 	rcu_assign_pointer(list_next_rcu(prev), new);
52 	prev->prev = new;
53 }
54 
55 #define	hlist_first_rcu(head)	(*((struct hlist_node **)(&(head)->first)))
56 #define	hlist_next_rcu(node)	(*((struct hlist_node **)(&(node)->next)))
57 #define	hlist_pprev_rcu(node)	(*((struct hlist_node **)((node)->pprev)))
58 
59 static inline void
60 hlist_add_behind_rcu(struct hlist_node *n, struct hlist_node *prev)
61 {
62 	n->next = prev->next;
63 	n->pprev = &prev->next;
64 	rcu_assign_pointer(hlist_next_rcu(prev), n);
65 	if (n->next)
66 		n->next->pprev = &n->next;
67 }
68 
69 #define	hlist_for_each_entry_rcu(pos, head, member)			\
70 	for (pos = hlist_entry_safe (rcu_dereference_raw(hlist_first_rcu(head)),\
71 	        typeof(*(pos)), member);				\
72 	     (pos);							\
73 	     pos = hlist_entry_safe(rcu_dereference_raw(hlist_next_rcu(	\
74 			&(pos)->member)), typeof(*(pos)), member))
75 
76 static inline void
77 hlist_del_rcu(struct hlist_node *n)
78 {
79 	struct hlist_node *next = n->next;
80 	struct hlist_node **pprev = n->pprev;
81 
82 	WRITE_ONCE(*pprev, next);
83 	if (next)
84 		next->pprev = pprev;
85 }
86 
87 static inline void
88 hlist_add_head_rcu(struct hlist_node *n, struct hlist_head *h)
89 {
90 	struct hlist_node *first = h->first;
91 
92 	n->next = first;
93 	n->pprev = &h->first;
94 	rcu_assign_pointer(hlist_first_rcu(h), n);
95 	if (first)
96 		first->pprev = &n->next;
97 }
98 
99 static inline void
100 hlist_del_init_rcu(struct hlist_node *n)
101 {
102 	if (!hlist_unhashed(n)) {
103 		hlist_del_rcu(n);
104 		n->pprev = NULL;
105 	}
106 }
107 
108 #endif					/* _LINUX_RCULIST_H_ */
109