2 * Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC.
3 * Copyright (C) 2007 The Regents of the University of California.
4 * Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
5 * Written by Brian Behlendorf <behlendorf1@llnl.gov>.
8 * This file is part of the SPL, Solaris Porting Layer.
10 * The SPL is free software; you can redistribute it and/or modify it
11 * under the terms of the GNU General Public License as published by the
12 * Free Software Foundation; either version 2 of the License, or (at your
13 * option) any later version.
15 * The SPL is distributed in the hope that it will be useful, but WITHOUT
16 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
17 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
20 * You should have received a copy of the GNU General Public License along
21 * with the SPL. If not, see <http://www.gnu.org/licenses/>.
27 #include <sys/types.h>
28 #include <sys/debug.h>
29 #include <linux/list.h>
32 * NOTE: I have implemented the Solaris list API in terms of the native
33 * linux API. This has certain advantages in terms of leveraging the linux
34 * list debugging infrastructure, but it also means that the internals of a
35 * list differ slightly than on Solaris. This is not a problem as long as
36 * all callers stick to the published API. The two major differences are:
38 * 1) A list_node_t is mapped to a linux list_head struct which changes
39 * the name of the list_next/list_prev pointers to next/prev respectively.
41 * 2) A list_node_t which is not attached to a list on Solaris is denoted
42 * by having its list_next/list_prev pointers set to NULL. Under linux
43 * the next/prev pointers are set to LIST_POISON1 and LIST_POISON2
44 * respectively. At this moment this only impacts the implementation
45 * of the list_link_init() and list_link_active() functions.
48 typedef struct list_head list_node_t;
53 list_node_t list_head;
56 #define list_d2l(a, obj) ((list_node_t *)(((char *)obj) + (a)->list_offset))
57 #define list_object(a, node) ((void *)(((char *)node) - (a)->list_offset))
60 list_is_empty(list_t *list)
62 return (list_empty(&list->list_head));
66 list_link_init(list_node_t *node)
68 node->next = LIST_POISON1;
69 node->prev = LIST_POISON2;
73 list_create(list_t *list, size_t size, size_t offset)
75 list->list_size = size;
76 list->list_offset = offset;
77 INIT_LIST_HEAD(&list->list_head);
81 list_destroy(list_t *list)
83 list_del(&list->list_head);
87 list_insert_head(list_t *list, void *object)
89 list_add(list_d2l(list, object), &list->list_head);
93 list_insert_tail(list_t *list, void *object)
95 list_add_tail(list_d2l(list, object), &list->list_head);
99 list_insert_after(list_t *list, void *object, void *nobject)
102 list_insert_head(list, nobject);
104 list_add(list_d2l(list, nobject), list_d2l(list, object));
108 list_insert_before(list_t *list, void *object, void *nobject)
111 list_insert_tail(list, nobject);
113 list_add_tail(list_d2l(list, nobject), list_d2l(list, object));
117 list_remove(list_t *list, void *object)
119 list_del(list_d2l(list, object));
123 list_remove_head(list_t *list)
125 list_node_t *head = list->list_head.next;
126 if (head == &list->list_head)
130 return (list_object(list, head));
134 list_remove_tail(list_t *list)
136 list_node_t *tail = list->list_head.prev;
137 if (tail == &list->list_head)
141 return (list_object(list, tail));
145 list_head(list_t *list)
147 if (list_is_empty(list))
150 return (list_object(list, list->list_head.next));
154 list_tail(list_t *list)
156 if (list_is_empty(list))
159 return (list_object(list, list->list_head.prev));
163 list_next(list_t *list, void *object)
165 list_node_t *node = list_d2l(list, object);
167 if (node->next != &list->list_head)
168 return (list_object(list, node->next));
174 list_prev(list_t *list, void *object)
176 list_node_t *node = list_d2l(list, object);
178 if (node->prev != &list->list_head)
179 return (list_object(list, node->prev));
185 list_link_active(list_node_t *node)
187 EQUIV(node->next == LIST_POISON1, node->prev == LIST_POISON2);
188 return (node->next != LIST_POISON1);
192 spl_list_move_tail(list_t *dst, list_t *src)
194 list_splice_init(&src->list_head, dst->list_head.prev);
197 #define list_move_tail(dst, src) spl_list_move_tail(dst, src)
200 list_link_replace(list_node_t *old_node, list_node_t *new_node)
202 new_node->next = old_node->next;
203 new_node->prev = old_node->prev;
204 old_node->prev->next = new_node;
205 old_node->next->prev = new_node;
206 list_link_init(old_node);
209 #endif /* SPL_LIST_H */