xref: /freebsd/sys/compat/linuxkpi/common/include/linux/rculist.h (revision c3f8f86efd5fdbf5701d41c47a7fc4cd3ccdc802)
1 /*-
2  * Copyright (c) 2015 François Tigeot
3  * Copyright (c) 2016-2020 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 #define	list_prev_rcu(head)	(*((struct list_head **)(&(head)->prev)))
41 
42 #define	list_for_each_entry_rcu(pos, head, member) \
43 	for (pos = list_entry_rcu((head)->next, typeof(*(pos)), member); \
44 	     &(pos)->member != (head);					\
45 	     pos = list_entry_rcu((pos)->member.next, typeof(*(pos)), member))
46 
47 static inline void
48 linux_list_add_rcu(struct list_head *new, struct list_head *prev,
49     struct list_head *next)
50 {
51 	new->next = next;
52 	new->prev = prev;
53 	rcu_assign_pointer(list_next_rcu(prev), new);
54 	next->prev = new;
55 }
56 
57 static inline void
58 list_add_rcu(struct list_head *new, struct list_head *head)
59 {
60 	linux_list_add_rcu(new, head, head->next);
61 }
62 
63 static inline void
64 list_add_tail_rcu(struct list_head *new, struct list_head *head)
65 {
66 	linux_list_add_rcu(new, head->prev, head);
67 }
68 
69 static inline void
70 __list_del_rcu(struct list_head *prev, struct list_head *next)
71 {
72 	next->prev = prev;
73 	rcu_assign_pointer(list_next_rcu(prev), next);
74 }
75 
76 static inline void
77 __list_del_entry_rcu(struct list_head *entry)
78 {
79 	__list_del_rcu(entry->prev, entry->next);
80 }
81 
82 static inline void
83 list_del_rcu(struct list_head *entry)
84 {
85 	__list_del_rcu(entry->prev, entry->next);
86 }
87 
88 #define	hlist_first_rcu(head)	(*((struct hlist_node **)(&(head)->first)))
89 #define	hlist_next_rcu(node)	(*((struct hlist_node **)(&(node)->next)))
90 #define	hlist_pprev_rcu(node)	(*((struct hlist_node **)((node)->pprev)))
91 
92 static inline void
93 hlist_add_behind_rcu(struct hlist_node *n, struct hlist_node *prev)
94 {
95 	n->next = prev->next;
96 	n->pprev = &prev->next;
97 	rcu_assign_pointer(hlist_next_rcu(prev), n);
98 	if (n->next)
99 		n->next->pprev = &n->next;
100 }
101 
102 #define	hlist_for_each_entry_rcu(pos, head, member)			\
103 	for (pos = hlist_entry_safe (rcu_dereference_raw(hlist_first_rcu(head)),\
104 	        typeof(*(pos)), member);				\
105 	     (pos);							\
106 	     pos = hlist_entry_safe(rcu_dereference_raw(hlist_next_rcu(	\
107 			&(pos)->member)), typeof(*(pos)), member))
108 
109 static inline void
110 hlist_del_rcu(struct hlist_node *n)
111 {
112 	struct hlist_node *next = n->next;
113 	struct hlist_node **pprev = n->pprev;
114 
115 	WRITE_ONCE(*pprev, next);
116 	if (next)
117 		next->pprev = pprev;
118 }
119 
120 static inline void
121 hlist_add_head_rcu(struct hlist_node *n, struct hlist_head *h)
122 {
123 	struct hlist_node *first = h->first;
124 
125 	n->next = first;
126 	n->pprev = &h->first;
127 	rcu_assign_pointer(hlist_first_rcu(h), n);
128 	if (first)
129 		first->pprev = &n->next;
130 }
131 
132 static inline void
133 hlist_del_init_rcu(struct hlist_node *n)
134 {
135 	if (!hlist_unhashed(n)) {
136 		hlist_del_rcu(n);
137 		n->pprev = NULL;
138 	}
139 }
140 
141 #endif					/* _LINUX_RCULIST_H_ */
142