| 1 | /* $NetBSD: list.h,v 1.5 2014/08/20 15:26:52 riastradh 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 | /* |
| 33 | * Notes on porting: |
| 34 | * |
| 35 | * - LIST_HEAD(x) means a declaration `struct list_head x = |
| 36 | * LIST_HEAD_INIT(x)' in Linux, but something else in NetBSD. |
| 37 | * Replace by the expansion. |
| 38 | * |
| 39 | * - The `_rcu' routines here are not actually pserialize(9)-safe. |
| 40 | * They need dependent read memory barriers added. Please fix this |
| 41 | * if you need to use them with pserialize(9). |
| 42 | */ |
| 43 | |
| 44 | #ifndef _LINUX_LIST_H_ |
| 45 | #define _LINUX_LIST_H_ |
| 46 | |
| 47 | #include <sys/null.h> |
| 48 | #include <sys/queue.h> |
| 49 | |
| 50 | #include <linux/kernel.h> |
| 51 | |
| 52 | /* |
| 53 | * Doubly-linked lists. |
| 54 | */ |
| 55 | |
| 56 | struct list_head { |
| 57 | struct list_head *prev; |
| 58 | struct list_head *next; |
| 59 | }; |
| 60 | |
| 61 | #define LIST_HEAD_INIT(name) { .prev = &(name), .next = &(name) } |
| 62 | |
| 63 | static inline void |
| 64 | INIT_LIST_HEAD(struct list_head *head) |
| 65 | { |
| 66 | head->prev = head; |
| 67 | head->next = head; |
| 68 | } |
| 69 | |
| 70 | static inline struct list_head * |
| 71 | list_first(const struct list_head *head) |
| 72 | { |
| 73 | return head->next; |
| 74 | } |
| 75 | |
| 76 | static inline struct list_head * |
| 77 | list_last(const struct list_head *head) |
| 78 | { |
| 79 | return head->prev; |
| 80 | } |
| 81 | |
| 82 | static inline struct list_head * |
| 83 | list_next(const struct list_head *node) |
| 84 | { |
| 85 | return node->next; |
| 86 | } |
| 87 | |
| 88 | static inline struct list_head * |
| 89 | list_prev(const struct list_head *node) |
| 90 | { |
| 91 | return node->prev; |
| 92 | } |
| 93 | |
| 94 | static inline int |
| 95 | list_empty(const struct list_head *head) |
| 96 | { |
| 97 | return (head->next == head); |
| 98 | } |
| 99 | |
| 100 | static inline int |
| 101 | list_is_singular(const struct list_head *head) |
| 102 | { |
| 103 | |
| 104 | if (list_empty(head)) |
| 105 | return false; |
| 106 | if (head->next != head->prev) |
| 107 | return false; |
| 108 | return true; |
| 109 | } |
| 110 | |
| 111 | static inline void |
| 112 | __list_add_between(struct list_head *prev, struct list_head *node, |
| 113 | struct list_head *next) |
| 114 | { |
| 115 | prev->next = node; |
| 116 | node->prev = prev; |
| 117 | node->next = next; |
| 118 | next->prev = node; |
| 119 | } |
| 120 | |
| 121 | static inline void |
| 122 | list_add(struct list_head *node, struct list_head *head) |
| 123 | { |
| 124 | __list_add_between(head, node, head->next); |
| 125 | } |
| 126 | |
| 127 | static inline void |
| 128 | list_add_tail(struct list_head *node, struct list_head *head) |
| 129 | { |
| 130 | __list_add_between(head->prev, node, head); |
| 131 | } |
| 132 | |
| 133 | static inline void |
| 134 | list_del(struct list_head *entry) |
| 135 | { |
| 136 | entry->prev->next = entry->next; |
| 137 | entry->next->prev = entry->prev; |
| 138 | } |
| 139 | |
| 140 | static inline void |
| 141 | __list_splice_between(struct list_head *prev, const struct list_head *list, |
| 142 | struct list_head *next) |
| 143 | { |
| 144 | struct list_head *first = list->next; |
| 145 | struct list_head *last = list->prev; |
| 146 | |
| 147 | first->prev = prev; |
| 148 | prev->next = first; |
| 149 | |
| 150 | last->next = next; |
| 151 | next->prev = last; |
| 152 | } |
| 153 | |
| 154 | static inline void |
| 155 | list_splice(const struct list_head *list, struct list_head *head) |
| 156 | { |
| 157 | if (!list_empty(list)) |
| 158 | __list_splice_between(head, list, head->next); |
| 159 | } |
| 160 | |
| 161 | static inline void |
| 162 | list_splice_tail(const struct list_head *list, struct list_head *head) |
| 163 | { |
| 164 | if (!list_empty(list)) |
| 165 | __list_splice_between(head->prev, list, head); |
| 166 | } |
| 167 | |
| 168 | static inline void |
| 169 | list_move(struct list_head *node, struct list_head *head) |
| 170 | { |
| 171 | list_del(node); |
| 172 | list_add(node, head); |
| 173 | } |
| 174 | |
| 175 | static inline void |
| 176 | list_move_tail(struct list_head *node, struct list_head *head) |
| 177 | { |
| 178 | list_del(node); |
| 179 | list_add_tail(node, head); |
| 180 | } |
| 181 | |
| 182 | static inline void |
| 183 | list_replace(struct list_head *old, struct list_head *new) |
| 184 | { |
| 185 | new->prev = old->prev; |
| 186 | old->prev->next = new; |
| 187 | new->next = old->next; |
| 188 | old->next->prev = new; |
| 189 | } |
| 190 | |
| 191 | static inline void |
| 192 | list_del_init(struct list_head *node) |
| 193 | { |
| 194 | list_del(node); |
| 195 | INIT_LIST_HEAD(node); |
| 196 | } |
| 197 | |
| 198 | #define list_entry(PTR, TYPE, FIELD) container_of(PTR, TYPE, FIELD) |
| 199 | #define list_first_entry(PTR, TYPE, FIELD) \ |
| 200 | list_entry(list_first((PTR)), TYPE, FIELD) |
| 201 | #define list_last_entry(PTR, TYPE, FIELD) \ |
| 202 | list_entry(list_last((PTR)), TYPE, FIELD) |
| 203 | #define list_next_entry(ENTRY, FIELD) \ |
| 204 | list_entry(list_next(&(ENTRY)->FIELD), typeof(*(ENTRY)), FIELD) |
| 205 | #define list_prev_entry(ENTRY, FIELD) \ |
| 206 | list_entry(list_prev(&(ENTRY)->FIELD), typeof(*(ENTRY)), FIELD) |
| 207 | |
| 208 | #define list_for_each(VAR, HEAD) \ |
| 209 | for ((VAR) = list_first((HEAD)); \ |
| 210 | (VAR) != (HEAD); \ |
| 211 | (VAR) = list_next((VAR))) |
| 212 | |
| 213 | #define list_for_each_safe(VAR, NEXT, HEAD) \ |
| 214 | for ((VAR) = list_first((HEAD)); \ |
| 215 | ((VAR) != (HEAD)) && ((NEXT) = list_next((VAR)), 1); \ |
| 216 | (VAR) = (NEXT)) |
| 217 | |
| 218 | #define list_for_each_entry(VAR, HEAD, FIELD) \ |
| 219 | for ((VAR) = list_entry(list_first((HEAD)), typeof(*(VAR)), FIELD); \ |
| 220 | &(VAR)->FIELD != (HEAD); \ |
| 221 | (VAR) = list_entry(list_next(&(VAR)->FIELD), typeof(*(VAR)), \ |
| 222 | FIELD)) |
| 223 | |
| 224 | #define list_for_each_entry_reverse(VAR, HEAD, FIELD) \ |
| 225 | for ((VAR) = list_entry(list_last((HEAD)), typeof(*(VAR)), FIELD); \ |
| 226 | &(VAR)->FIELD != (HEAD); \ |
| 227 | (VAR) = list_entry(list_prev(&(VAR)->FIELD), typeof(*(VAR)), \ |
| 228 | FIELD)) |
| 229 | |
| 230 | #define list_for_each_entry_safe(VAR, NEXT, HEAD, FIELD) \ |
| 231 | for ((VAR) = list_entry(list_first((HEAD)), typeof(*(VAR)), FIELD); \ |
| 232 | (&(VAR)->FIELD != (HEAD)) && \ |
| 233 | ((NEXT) = list_entry(list_next(&(VAR)->FIELD), \ |
| 234 | typeof(*(VAR)), FIELD), 1); \ |
| 235 | (VAR) = (NEXT)) |
| 236 | |
| 237 | #define list_for_each_entry_continue(VAR, HEAD, FIELD) \ |
| 238 | for ((VAR) = list_next_entry((VAR), FIELD); \ |
| 239 | &(VAR)->FIELD != (HEAD); \ |
| 240 | (VAR) = list_next_entry((VAR), FIELD)) |
| 241 | |
| 242 | #define list_for_each_entry_continue_reverse(VAR, HEAD, FIELD) \ |
| 243 | for ((VAR) = list_prev_entry((VAR), FIELD); \ |
| 244 | &(VAR)->FIELD != (HEAD); \ |
| 245 | (VAR) = list_prev_entry((VAR), FIELD)) |
| 246 | |
| 247 | #define list_for_each_entry_safe_from(VAR, NEXT, HEAD, FIELD) \ |
| 248 | for (; \ |
| 249 | (&(VAR)->FIELD != (HEAD)) && \ |
| 250 | ((NEXT) = list_next_entry((VAR), FIELD)); \ |
| 251 | (VAR) = (NEXT)) |
| 252 | |
| 253 | /* |
| 254 | * `H'ead-only/`H'ash-table doubly-linked lists. |
| 255 | */ |
| 256 | |
| 257 | LIST_HEAD(hlist_head, hlist_node); |
| 258 | struct hlist_node { |
| 259 | LIST_ENTRY(hlist_node) hln_entry; |
| 260 | }; |
| 261 | |
| 262 | static inline struct hlist_node * |
| 263 | hlist_first(struct hlist_head *head) |
| 264 | { |
| 265 | return LIST_FIRST(head); |
| 266 | } |
| 267 | |
| 268 | static inline struct hlist_node * |
| 269 | hlist_next(struct hlist_node *node) |
| 270 | { |
| 271 | return LIST_NEXT(node, hln_entry); |
| 272 | } |
| 273 | |
| 274 | static inline void |
| 275 | hlist_add_head(struct hlist_node *node, struct hlist_head *head) |
| 276 | { |
| 277 | LIST_INSERT_HEAD(head, node, hln_entry); |
| 278 | } |
| 279 | |
| 280 | static inline void |
| 281 | hlist_add_after(struct hlist_node *node, struct hlist_node *next) |
| 282 | { |
| 283 | LIST_INSERT_AFTER(node, next, hln_entry); |
| 284 | } |
| 285 | |
| 286 | static inline void |
| 287 | hlist_del(struct hlist_node *node) |
| 288 | { |
| 289 | LIST_REMOVE(node, hln_entry); |
| 290 | } |
| 291 | |
| 292 | static inline void |
| 293 | hlist_del_init(struct hlist_node *node) |
| 294 | { |
| 295 | LIST_REMOVE(node, hln_entry); |
| 296 | } |
| 297 | |
| 298 | #define hlist_entry(PTR, TYPE, FIELD) container_of(PTR, TYPE, FIELD) |
| 299 | #define hlist_for_each(VAR, HEAD) LIST_FOREACH(VAR, HEAD, hln_entry) |
| 300 | #define hlist_for_each_safe(VAR, NEXT, HEAD) \ |
| 301 | LIST_FOREACH_SAFE(VAR, HEAD, hln_entry, NEXT) |
| 302 | |
| 303 | #define hlist_for_each_entry(VAR, HEAD, FIELD) \ |
| 304 | for ((VAR) = hlist_entry(LIST_FIRST((HEAD)), typeof(*(VAR)), FIELD); \ |
| 305 | &(VAR)->FIELD != NULL; \ |
| 306 | (VAR) = hlist_entry(LIST_NEXT(&(VAR)->FIELD, hln_entry), \ |
| 307 | typeof(*(VAR)), FIELD)) |
| 308 | |
| 309 | /* |
| 310 | * XXX The nominally RCU-safe APIs below lack dependent read barriers, |
| 311 | * so they're not actually RCU-safe...on the alpha, anyway. Someone^TM |
| 312 | * should fix this. |
| 313 | */ |
| 314 | |
| 315 | #define hlist_add_after_rcu hlist_add_after |
| 316 | #define hlist_add_head_rcu hlist_add_head |
| 317 | #define hlist_del_init_rcu hlist_del_init |
| 318 | #define hlist_for_each_entry_rcu hlist_for_each_entry |
| 319 | |
| 320 | #endif /* _LINUX_LIST_H_ */ |
| 321 | |