1 /*- 2 * Copyright (c) 2010 Isilon Systems, Inc. 3 * Copyright (c) 2010 iX Systems, Inc. 4 * Copyright (c) 2010 Panasas, Inc. 5 * Copyright (c) 2013-2016 Mellanox Technologies, Ltd. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice unmodified, this list of conditions, and the following 13 * disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 */ 29 #ifndef _LINUX_LIST_H_ 30 #define _LINUX_LIST_H_ 31 32 #define container_of(ptr, type, member) \ 33 ({ \ 34 const __typeof(((type *)0)->member) *__p = (ptr); \ 35 (type *)((uintptr_t)__p - offsetof(type, member)); \ 36 }) 37 38 #define LINUX_LIST_HEAD_INIT(name) { &(name), &(name) } 39 40 #define LINUX_LIST_HEAD(name) \ 41 struct list_head name = LINUX_LIST_HEAD_INIT(name) 42 43 #ifndef LIST_HEAD_DEF 44 #define LIST_HEAD_DEF 45 struct list_head { 46 struct list_head *next; 47 struct list_head *prev; 48 }; 49 #endif 50 51 #define barrier() __asm__ __volatile__("": : :"memory") 52 53 54 #define ACCESS_ONCE(x) (*(volatile __typeof(x) *)&(x)) 55 56 #define WRITE_ONCE(x,v) do { \ 57 barrier(); \ 58 ACCESS_ONCE(x) = (v); \ 59 barrier(); \ 60 } while (0) 61 62 #define READ_ONCE(x) ({ \ 63 __typeof(x) __var = ({ \ 64 barrier(); \ 65 ACCESS_ONCE(x); \ 66 }); \ 67 barrier(); \ 68 __var; \ 69 }) 70 71 static inline void 72 INIT_LIST_HEAD(struct list_head *list) 73 { 74 75 list->next = list->prev = list; 76 } 77 78 static inline int 79 list_empty(const struct list_head *head) 80 { 81 82 return (head->next == head); 83 } 84 85 static inline int 86 list_empty_careful(const struct list_head *head) 87 { 88 struct list_head *next = head->next; 89 90 return ((next == head) && (next == head->prev)); 91 } 92 93 static inline void 94 __list_del(struct list_head *prev, struct list_head *next) 95 { 96 next->prev = prev; 97 WRITE_ONCE(prev->next, next); 98 } 99 100 static inline void 101 __list_del_entry(struct list_head *entry) 102 { 103 104 __list_del(entry->prev, entry->next); 105 } 106 107 static inline void 108 list_del(struct list_head *entry) 109 { 110 111 __list_del(entry->prev, entry->next); 112 } 113 114 static inline void 115 list_replace(struct list_head *old, struct list_head *new) 116 { 117 new->next = old->next; 118 new->next->prev = new; 119 new->prev = old->prev; 120 new->prev->next = new; 121 } 122 123 static inline void 124 list_replace_init(struct list_head *old, struct list_head *new) 125 { 126 list_replace(old, new); 127 INIT_LIST_HEAD(old); 128 } 129 130 static inline void 131 linux_list_add(struct list_head *new, struct list_head *prev, 132 struct list_head *next) 133 { 134 135 next->prev = new; 136 new->next = next; 137 new->prev = prev; 138 prev->next = new; 139 } 140 141 static inline void 142 list_del_init(struct list_head *entry) 143 { 144 145 list_del(entry); 146 INIT_LIST_HEAD(entry); 147 } 148 149 #define list_entry(ptr, type, field) container_of(ptr, type, field) 150 151 #define list_first_entry(ptr, type, member) \ 152 list_entry((ptr)->next, type, member) 153 154 #define list_last_entry(ptr, type, member) \ 155 list_entry((ptr)->prev, type, member) 156 157 #define list_first_entry_or_null(ptr, type, member) \ 158 (!list_empty(ptr) ? list_first_entry(ptr, type, member) : NULL) 159 160 #define list_next_entry(ptr, member) \ 161 list_entry(((ptr)->member.next), typeof(*(ptr)), member) 162 163 #define list_safe_reset_next(ptr, n, member) \ 164 (n) = list_next_entry(ptr, member) 165 166 #define list_prev_entry(ptr, member) \ 167 list_entry(((ptr)->member.prev), typeof(*(ptr)), member) 168 169 #define list_for_each(p, head) \ 170 for (p = (head)->next; p != (head); p = (p)->next) 171 172 #define list_for_each_safe(p, n, head) \ 173 for (p = (head)->next, n = (p)->next; p != (head); p = n, n = (p)->next) 174 175 #define list_for_each_entry(p, h, field) \ 176 for (p = list_entry((h)->next, typeof(*p), field); &(p)->field != (h); \ 177 p = list_entry((p)->field.next, typeof(*p), field)) 178 179 #define list_for_each_entry_safe(p, n, h, field) \ 180 for (p = list_entry((h)->next, typeof(*p), field), \ 181 n = list_entry((p)->field.next, typeof(*p), field); &(p)->field != (h);\ 182 p = n, n = list_entry(n->field.next, typeof(*n), field)) 183 184 #define list_for_each_entry_from(p, h, field) \ 185 for ( ; &(p)->field != (h); \ 186 p = list_entry((p)->field.next, typeof(*p), field)) 187 188 #define list_for_each_entry_continue(p, h, field) \ 189 for (p = list_next_entry((p), field); &(p)->field != (h); \ 190 p = list_next_entry((p), field)) 191 192 #define list_for_each_entry_safe_from(pos, n, head, member) \ 193 for (n = list_entry((pos)->member.next, typeof(*pos), member); \ 194 &(pos)->member != (head); \ 195 pos = n, n = list_entry(n->member.next, typeof(*n), member)) 196 197 #define list_for_each_entry_reverse(p, h, field) \ 198 for (p = list_entry((h)->prev, typeof(*p), field); &(p)->field != (h); \ 199 p = list_entry((p)->field.prev, typeof(*p), field)) 200 201 #define list_for_each_entry_safe_reverse(p, n, h, field) \ 202 for (p = list_entry((h)->prev, typeof(*p), field), \ 203 n = list_entry((p)->field.prev, typeof(*p), field); &(p)->field != (h); \ 204 p = n, n = list_entry(n->field.prev, typeof(*n), field)) 205 206 #define list_for_each_entry_continue_reverse(p, h, field) \ 207 for (p = list_entry((p)->field.prev, typeof(*p), field); &(p)->field != (h); \ 208 p = list_entry((p)->field.prev, typeof(*p), field)) 209 210 #define list_for_each_prev(p, h) for (p = (h)->prev; p != (h); p = (p)->prev) 211 212 static inline void 213 list_add(struct list_head *new, struct list_head *head) 214 { 215 216 linux_list_add(new, head, head->next); 217 } 218 219 static inline void 220 list_add_tail(struct list_head *new, struct list_head *head) 221 { 222 223 linux_list_add(new, head->prev, head); 224 } 225 226 static inline void 227 list_move(struct list_head *list, struct list_head *head) 228 { 229 230 list_del(list); 231 list_add(list, head); 232 } 233 234 static inline void 235 list_move_tail(struct list_head *entry, struct list_head *head) 236 { 237 238 list_del(entry); 239 list_add_tail(entry, head); 240 } 241 242 static inline void 243 linux_list_splice(const struct list_head *list, struct list_head *prev, 244 struct list_head *next) 245 { 246 struct list_head *first; 247 struct list_head *last; 248 249 if (list_empty(list)) 250 return; 251 first = list->next; 252 last = list->prev; 253 first->prev = prev; 254 prev->next = first; 255 last->next = next; 256 next->prev = last; 257 } 258 259 static inline void 260 list_splice(const struct list_head *list, struct list_head *head) 261 { 262 263 linux_list_splice(list, head, head->next); 264 } 265 266 static inline void 267 list_splice_tail(struct list_head *list, struct list_head *head) 268 { 269 270 linux_list_splice(list, head->prev, head); 271 } 272 273 static inline void 274 list_splice_init(struct list_head *list, struct list_head *head) 275 { 276 277 linux_list_splice(list, head, head->next); 278 INIT_LIST_HEAD(list); 279 } 280 281 static inline void 282 list_splice_tail_init(struct list_head *list, struct list_head *head) 283 { 284 285 linux_list_splice(list, head->prev, head); 286 INIT_LIST_HEAD(list); 287 } 288 289 #undef LIST_HEAD 290 #define LIST_HEAD(name) struct list_head name = { &(name), &(name) } 291 292 293 struct hlist_head { 294 struct hlist_node *first; 295 }; 296 297 struct hlist_node { 298 struct hlist_node *next, **pprev; 299 }; 300 301 #define HLIST_HEAD_INIT { } 302 #define HLIST_HEAD(name) struct hlist_head name = HLIST_HEAD_INIT 303 #define INIT_HLIST_HEAD(head) (head)->first = NULL 304 #define INIT_HLIST_NODE(node) \ 305 do { \ 306 (node)->next = NULL; \ 307 (node)->pprev = NULL; \ 308 } while (0) 309 310 static inline int 311 hlist_unhashed(const struct hlist_node *h) 312 { 313 314 return !h->pprev; 315 } 316 317 static inline int 318 hlist_empty(const struct hlist_head *h) 319 { 320 321 return !h->first; 322 } 323 324 static inline void 325 hlist_del(struct hlist_node *n) 326 { 327 328 if (n->next) 329 n->next->pprev = n->pprev; 330 *n->pprev = n->next; 331 } 332 333 static inline void 334 hlist_del_init(struct hlist_node *n) 335 { 336 337 if (hlist_unhashed(n)) 338 return; 339 hlist_del(n); 340 INIT_HLIST_NODE(n); 341 } 342 343 static inline void 344 hlist_add_head(struct hlist_node *n, struct hlist_head *h) 345 { 346 347 n->next = h->first; 348 if (h->first) 349 h->first->pprev = &n->next; 350 h->first = n; 351 n->pprev = &h->first; 352 } 353 354 static inline void 355 hlist_add_before(struct hlist_node *n, struct hlist_node *next) 356 { 357 358 n->pprev = next->pprev; 359 n->next = next; 360 next->pprev = &n->next; 361 *(n->pprev) = n; 362 } 363 364 static inline void 365 hlist_add_after(struct hlist_node *n, struct hlist_node *next) 366 { 367 368 next->next = n->next; 369 n->next = next; 370 next->pprev = &n->next; 371 if (next->next) 372 next->next->pprev = &next->next; 373 } 374 375 static inline void 376 hlist_move_list(struct hlist_head *old, struct hlist_head *new) 377 { 378 379 new->first = old->first; 380 if (new->first) 381 new->first->pprev = &new->first; 382 old->first = NULL; 383 } 384 385 static inline int list_is_singular(const struct list_head *head) 386 { 387 return !list_empty(head) && (head->next == head->prev); 388 } 389 390 static inline void __list_cut_position(struct list_head *list, 391 struct list_head *head, struct list_head *entry) 392 { 393 struct list_head *new_first = entry->next; 394 list->next = head->next; 395 list->next->prev = list; 396 list->prev = entry; 397 entry->next = list; 398 head->next = new_first; 399 new_first->prev = head; 400 } 401 402 static inline void list_cut_position(struct list_head *list, 403 struct list_head *head, struct list_head *entry) 404 { 405 if (list_empty(head)) 406 return; 407 if (list_is_singular(head) && 408 (head->next != entry && head != entry)) 409 return; 410 if (entry == head) 411 INIT_LIST_HEAD(list); 412 else 413 __list_cut_position(list, head, entry); 414 } 415 416 static inline int list_is_last(const struct list_head *list, 417 const struct list_head *head) 418 { 419 return list->next == head; 420 } 421 422 #define hlist_entry(ptr, type, field) container_of(ptr, type, field) 423 424 #define hlist_for_each(p, head) \ 425 for (p = (head)->first; p; p = (p)->next) 426 427 #define hlist_for_each_safe(p, n, head) \ 428 for (p = (head)->first; p && ({ n = (p)->next; 1; }); p = n) 429 430 #define hlist_entry_safe(ptr, type, member) \ 431 ((ptr) ? hlist_entry(ptr, type, member) : NULL) 432 433 #define hlist_for_each_entry(pos, head, member) \ 434 for (pos = hlist_entry_safe((head)->first, typeof(*(pos)), member);\ 435 pos; \ 436 pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member)) 437 438 #define hlist_for_each_entry_continue(pos, member) \ 439 for (pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member); \ 440 (pos); \ 441 pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member)) 442 443 #define hlist_for_each_entry_from(pos, member) \ 444 for (; (pos); \ 445 pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member)) 446 447 #define hlist_for_each_entry_safe(pos, n, head, member) \ 448 for (pos = hlist_entry_safe((head)->first, typeof(*(pos)), member); \ 449 (pos) && ({ n = (pos)->member.next; 1; }); \ 450 pos = hlist_entry_safe(n, typeof(*(pos)), member)) 451 452 extern void list_sort(void *priv, struct list_head *head, int (*cmp)(void *priv, 453 struct list_head *a, struct list_head *b)); 454 455 #endif /* _LINUX_LIST_H_ */ 456