X-Git-Url: http://git.archive.openwrt.org/?p=project%2Flibubox.git;a=blobdiff_plain;f=list.h;h=ab52acff2f82ffbe41592144f5f193b161090521;hp=e8271d0042ca74b0b01603989f87b65d8e2feb29;hb=0c2fbbca80a242280e5bb8b079184479c9abfa6f;hpb=82ce342055ec8f7a0235d46f5332014eb3f69216 diff --git a/list.h b/list.h index e8271d0..ab52acf 100644 --- a/list.h +++ b/list.h @@ -1,612 +1,208 @@ -#ifndef _LINUX_LIST_H -#define _LINUX_LIST_H +/*- + * Copyright (c) 2011 Felix Fietkau + * Copyright (c) 2010 Isilon Systems, Inc. + * Copyright (c) 2010 iX Systems, Inc. + * Copyright (c) 2010 Panasas, Inc. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice unmodified, this list of conditions, and the following + * disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#ifndef _LINUX_LIST_H_ +#define _LINUX_LIST_H_ #include -/** - * container_of - cast a member of a structure out to the containing structure - * @ptr: the pointer to the member. - * @type: the type of the container struct this is embedded in. - * @member: the name of the member within the struct. - * - */ -#ifndef container_of -#define container_of(ptr, type, member) ( \ - (type *)( (char *)ptr - offsetof(type,member) )) -#endif +#include +#define prefetch(x) -/* - * Simple doubly linked list implementation. - * - * Some of the internal functions ("__xxx") are useful when - * manipulating whole lists rather than single entries, as - * sometimes we already know the next/prev entries and we can - * generate better code by using them directly rather than - * using the generic single-entry routines. - */ +#ifndef container_of +#define container_of(ptr, type, member) \ + ({ \ + const typeof(((type *) NULL)->member) *__mptr = (ptr); \ + (type *) ((char *) __mptr - offsetof(type, member)); \ + }) +#endif struct list_head { - struct list_head *next, *prev; + struct list_head *next; + struct list_head *prev; }; #define LIST_HEAD_INIT(name) { &(name), &(name) } +#undef LIST_HEAD +#define LIST_HEAD(name) struct list_head name = LIST_HEAD_INIT(name) -#define LIST_HEAD(name) \ - struct list_head name = LIST_HEAD_INIT(name) - -static inline void INIT_LIST_HEAD(struct list_head *list) +static inline void +INIT_LIST_HEAD(struct list_head *list) { - list->next = list; - list->prev = list; + list->next = list->prev = list; } -/* - * Insert a new entry between two known consecutive entries. - * - * This is only for internal list manipulation where we know - * the prev/next entries already! - */ -static inline void __list_add(struct list_head *new, - struct list_head *prev, - struct list_head *next) +static inline bool +list_empty(const struct list_head *head) { - next->prev = new; - new->next = next; - new->prev = prev; - prev->next = new; + return (head->next == head); } -/** - * list_add - add a new entry - * @new: new entry to be added - * @head: list head to add it after - * - * Insert a new entry after the specified head. - * This is good for implementing stacks. - */ -static inline void list_add(struct list_head *new, struct list_head *head) +static inline bool +list_is_first(const struct list_head *list, + const struct list_head *head) { - __list_add(new, head, head->next); + return list->prev == head; } - -/** - * list_add_tail - add a new entry - * @new: new entry to be added - * @head: list head to add it before - * - * Insert a new entry before the specified head. - * This is useful for implementing queues. - */ -static inline void list_add_tail(struct list_head *new, struct list_head *head) +static inline bool +list_is_last(const struct list_head *list, + const struct list_head *head) { - __list_add(new, head->prev, head); + return list->next == head; } - -/* - * Delete a list entry by making the prev/next entries - * point to each other. - * - * This is only for internal list manipulation where we know - * the prev/next entries already! - */ -static inline void __list_del(struct list_head * prev, struct list_head * next) +static inline void +_list_del(struct list_head *entry) { - next->prev = prev; - prev->next = next; + entry->next->prev = entry->prev; + entry->prev->next = entry->next; } -/** - * list_del - deletes entry from list. - * @entry: the element to delete from the list. - * Note: list_empty() on entry does not return true after this, the entry is - * in an undefined state. - */ -static inline void list_del(struct list_head *entry) +static inline void +list_del(struct list_head *entry) { - __list_del(entry->prev, entry->next); - entry->next = NULL; - entry->prev = NULL; + _list_del(entry); + entry->next = entry->prev = NULL; } -/** - * list_replace - replace old entry by new one - * @old : the element to be replaced - * @new : the new element to insert - * - * If @old was empty, it will be overwritten. - */ -static inline void list_replace(struct list_head *old, - struct list_head *new) +static inline void +_list_add(struct list_head *_new, struct list_head *prev, + struct list_head *next) { - new->next = old->next; - new->next->prev = new; - new->prev = old->prev; - new->prev->next = new; -} -static inline void list_replace_init(struct list_head *old, - struct list_head *new) -{ - list_replace(old, new); - INIT_LIST_HEAD(old); + next->prev = _new; + _new->next = next; + _new->prev = prev; + prev->next = _new; } -/** - * list_del_init - deletes entry from list and reinitialize it. - * @entry: the element to delete from the list. - */ -static inline void list_del_init(struct list_head *entry) +static inline void +list_del_init(struct list_head *entry) { - __list_del(entry->prev, entry->next); + _list_del(entry); INIT_LIST_HEAD(entry); } -/** - * list_move - delete from one list and add as another's head - * @list: the entry to move - * @head: the head that will precede our entry - */ -static inline void list_move(struct list_head *list, struct list_head *head) -{ - __list_del(list->prev, list->next); - list_add(list, head); -} +#define list_entry(ptr, type, field) container_of(ptr, type, field) +#define list_first_entry(ptr, type, field) list_entry((ptr)->next, type, field) +#define list_last_entry(ptr, type, field) list_entry((ptr)->prev, type, field) -/** - * list_move_tail - delete from one list and add as another's tail - * @list: the entry to move - * @head: the head that will follow our entry - */ -static inline void list_move_tail(struct list_head *list, - struct list_head *head) -{ - __list_del(list->prev, list->next); - list_add_tail(list, head); -} +#define list_for_each(p, head) \ + for (p = (head)->next; p != (head); p = p->next) -/** - * list_is_first - tests whether @list is the first entry in list @head - * @list: the entry to test - * @head: the head of the list - */ -static inline int list_is_first(const struct list_head *list, - const struct list_head *head) -{ - return list->prev == head; -} +#define list_for_each_safe(p, n, head) \ + for (p = (head)->next, n = p->next; p != (head); p = n, n = p->next) -/** - * list_is_last - tests whether @list is the last entry in list @head - * @list: the entry to test - * @head: the head of the list - */ -static inline int list_is_last(const struct list_head *list, - const struct list_head *head) -{ - return list->next == head; -} +#define list_for_each_entry(p, h, field) \ + for (p = list_first_entry(h, typeof(*p), field); &p->field != (h); \ + p = list_entry(p->field.next, typeof(*p), field)) -/** - * list_empty - tests whether a list is empty - * @head: the list to test. - */ -static inline int list_empty(const struct list_head *head) -{ - return head->next == head; -} +#define list_for_each_entry_safe(p, n, h, field) \ + for (p = list_first_entry(h, typeof(*p), field), \ + n = list_entry(p->field.next, typeof(*p), field); &p->field != (h);\ + p = n, n = list_entry(n->field.next, typeof(*n), field)) -/** - * list_empty_careful - tests whether a list is empty and not being modified - * @head: the list to test - * - * Description: - * tests whether a list is empty _and_ checks that no other CPU might be - * in the process of modifying either member (next or prev) - * - * NOTE: using list_empty_careful() without synchronization - * can only be safe if the only activity that can happen - * to the list entry is list_del_init(). Eg. it cannot be used - * if another CPU could re-list_add() it. - */ -static inline int list_empty_careful(const struct list_head *head) -{ - struct list_head *next = head->next; - return (next == head) && (next == head->prev); -} - -static inline void __list_splice(struct list_head *list, - struct list_head *head) -{ - struct list_head *first = list->next; - struct list_head *last = list->prev; - struct list_head *at = head->next; - - first->prev = head; - head->next = first; +#define list_for_each_entry_reverse(p, h, field) \ + for (p = list_last_entry(h, typeof(*p), field); &p->field != (h); \ + p = list_entry(p->field.prev, typeof(*p), field)) - last->next = at; - at->prev = last; -} +#define list_for_each_prev(p, h) for (p = (h)->prev; p != (h); p = p->prev) +#define list_for_each_prev_safe(p, n, h) for (p = (h)->prev, n = p->prev; p != (h); p = n, n = p->prev) -/** - * list_splice - join two lists - * @list: the new list to add. - * @head: the place to add it in the first list. - */ -static inline void list_splice(struct list_head *list, struct list_head *head) +static inline void +list_add(struct list_head *_new, struct list_head *head) { - if (!list_empty(list)) - __list_splice(list, head); + _list_add(_new, head, head->next); } -/** - * list_splice_init - join two lists and reinitialise the emptied list. - * @list: the new list to add. - * @head: the place to add it in the first list. - * - * The list at @list is reinitialised - */ -static inline void list_splice_init(struct list_head *list, - struct list_head *head) +static inline void +list_add_tail(struct list_head *_new, struct list_head *head) { - if (!list_empty(list)) { - __list_splice(list, head); - INIT_LIST_HEAD(list); - } + _list_add(_new, head->prev, head); } -/** - * list_entry - get the struct for this entry - * @ptr: the &struct list_head pointer. - * @type: the type of the struct this is embedded in. - * @member: the name of the list_struct within the struct. - */ -#define list_entry(ptr, type, member) \ - container_of(ptr, type, member) - -/** - * list_first_entry - get the first element from a list - * @ptr: the list head to take the element from. - * @type: the type of the struct this is embedded in. - * @member: the name of the list_struct within the struct. - * - * Note, that list is expected to be not empty. - */ -#define list_first_entry(ptr, type, member) \ - list_entry((ptr)->next, type, member) - -/** - * list_for_each - iterate over a list - * @pos: the &struct list_head to use as a loop cursor. - * @head: the head for your list. - */ -#define list_for_each(pos, head) \ - for (pos = (head)->next; pos != (head); \ - pos = pos->next) - -/** - * __list_for_each - iterate over a list - * @pos: the &struct list_head to use as a loop cursor. - * @head: the head for your list. - * - * This variant differs from list_for_each() in that it's the - * simplest possible list iteration code, no prefetching is done. - * Use this for code that knows the list to be very short (empty - * or 1 entry) most of the time. - */ -#define __list_for_each(pos, head) \ - for (pos = (head)->next; pos != (head); pos = pos->next) - -/** - * list_for_each_prev - iterate over a list backwards - * @pos: the &struct list_head to use as a loop cursor. - * @head: the head for your list. - */ -#define list_for_each_prev(pos, head) \ - for (pos = (head)->prev; pos != (head); \ - pos = pos->prev) - -/** - * list_for_each_safe - iterate over a list safe against removal of list entry - * @pos: the &struct list_head to use as a loop cursor. - * @n: another &struct list_head to use as temporary storage - * @head: the head for your list. - */ -#define list_for_each_safe(pos, n, head) \ - for (pos = (head)->next, n = pos->next; pos != (head); \ - pos = n, n = pos->next) - -/** - * list_for_each_prev_safe - iterate over a list backwards safe against removal of list entry - * @pos: the &struct list_head to use as a loop cursor. - * @n: another &struct list_head to use as temporary storage - * @head: the head for your list. - */ -#define list_for_each_prev_safe(pos, n, head) \ - for (pos = (head)->prev, n = pos->prev; \ - pos != (head); \ - pos = n, n = pos->prev) - -/** - * list_for_each_entry - iterate over list of given type - * @pos: the type * to use as a loop cursor. - * @head: the head for your list. - * @member: the name of the list_struct within the struct. - */ -#define list_for_each_entry(pos, head, member) \ - for (pos = list_entry((head)->next, typeof(*pos), member); \ - &pos->member != (head); \ - pos = list_entry(pos->member.next, typeof(*pos), member)) - -/** - * list_for_each_entry_reverse - iterate backwards over list of given type. - * @pos: the type * to use as a loop cursor. - * @head: the head for your list. - * @member: the name of the list_struct within the struct. - */ -#define list_for_each_entry_reverse(pos, head, member) \ - for (pos = list_entry((head)->prev, typeof(*pos), member); \ - &pos->member != (head); \ - pos = list_entry(pos->member.prev, typeof(*pos), member)) - -/** - * list_prepare_entry - prepare a pos entry for use in list_for_each_entry_continue() - * @pos: the type * to use as a start point - * @head: the head of the list - * @member: the name of the list_struct within the struct. - * - * Prepares a pos entry for use as a start point in list_for_each_entry_continue(). - */ -#define list_prepare_entry(pos, head, member) \ - ((pos) ? : list_entry(head, typeof(*pos), member)) - -/** - * list_for_each_entry_continue - continue iteration over list of given type - * @pos: the type * to use as a loop cursor. - * @head: the head for your list. - * @member: the name of the list_struct within the struct. - * - * Continue to iterate over list of given type, continuing after - * the current position. - */ -#define list_for_each_entry_continue(pos, head, member) \ - for (pos = list_entry(pos->member.next, typeof(*pos), member); \ - &pos->member != (head); \ - pos = list_entry(pos->member.next, typeof(*pos), member)) - -/** - * list_for_each_entry_continue_reverse - iterate backwards from the given point - * @pos: the type * to use as a loop cursor. - * @head: the head for your list. - * @member: the name of the list_struct within the struct. - * - * Start to iterate over list of given type backwards, continuing after - * the current position. - */ -#define list_for_each_entry_continue_reverse(pos, head, member) \ - for (pos = list_entry(pos->member.prev, typeof(*pos), member); \ - &pos->member != (head); \ - pos = list_entry(pos->member.prev, typeof(*pos), member)) - -/** - * list_for_each_entry_from - iterate over list of given type from the current point - * @pos: the type * to use as a loop cursor. - * @head: the head for your list. - * @member: the name of the list_struct within the struct. - * - * Iterate over list of given type, continuing from current position. - */ -#define list_for_each_entry_from(pos, head, member) \ - for (; &pos->member != (head); \ - pos = list_entry(pos->member.next, typeof(*pos), member)) - -/** - * list_for_each_entry_safe - iterate over list of given type safe against removal of list entry - * @pos: the type * to use as a loop cursor. - * @n: another type * to use as temporary storage - * @head: the head for your list. - * @member: the name of the list_struct within the struct. - */ -#define list_for_each_entry_safe(pos, n, head, member) \ - for (pos = list_entry((head)->next, typeof(*pos), member), \ - n = list_entry(pos->member.next, typeof(*pos), member); \ - &pos->member != (head); \ - pos = n, n = list_entry(n->member.next, typeof(*n), member)) - -/** - * list_for_each_entry_safe_continue - * @pos: the type * to use as a loop cursor. - * @n: another type * to use as temporary storage - * @head: the head for your list. - * @member: the name of the list_struct within the struct. - * - * Iterate over list of given type, continuing after current point, - * safe against removal of list entry. - */ -#define list_for_each_entry_safe_continue(pos, n, head, member) \ - for (pos = list_entry(pos->member.next, typeof(*pos), member), \ - n = list_entry(pos->member.next, typeof(*pos), member); \ - &pos->member != (head); \ - pos = n, n = list_entry(n->member.next, typeof(*n), member)) - -/** - * list_for_each_entry_safe_from - * @pos: the type * to use as a loop cursor. - * @n: another type * to use as temporary storage - * @head: the head for your list. - * @member: the name of the list_struct within the struct. - * - * Iterate over list of given type from current point, safe against - * removal of list entry. - */ -#define list_for_each_entry_safe_from(pos, n, head, member) \ - for (n = list_entry(pos->member.next, typeof(*pos), member); \ - &pos->member != (head); \ - pos = n, n = list_entry(n->member.next, typeof(*n), member)) - -/** - * list_for_each_entry_safe_reverse - * @pos: the type * to use as a loop cursor. - * @n: another type * to use as temporary storage - * @head: the head for your list. - * @member: the name of the list_struct within the struct. - * - * Iterate backwards over list of given type, safe against removal - * of list entry. - */ -#define list_for_each_entry_safe_reverse(pos, n, head, member) \ - for (pos = list_entry((head)->prev, typeof(*pos), member), \ - n = list_entry(pos->member.prev, typeof(*pos), member); \ - &pos->member != (head); \ - pos = n, n = list_entry(n->member.prev, typeof(*n), member)) - -/* - * Double linked lists with a single pointer list head. - * Mostly useful for hash tables where the two pointer list head is - * too wasteful. - * You lose the ability to access the tail in O(1). - */ - -struct hlist_head { - struct hlist_node *first; -}; - -struct hlist_node { - struct hlist_node *next, **pprev; -}; - -#define HLIST_HEAD_INIT { .first = NULL } -#define HLIST_HEAD(name) struct hlist_head name = { .first = NULL } -#define INIT_HLIST_HEAD(ptr) ((ptr)->first = NULL) -static inline void INIT_HLIST_NODE(struct hlist_node *h) +static inline void +list_move(struct list_head *list, struct list_head *head) { - h->next = NULL; - h->pprev = NULL; + _list_del(list); + list_add(list, head); } -static inline int hlist_unhashed(const struct hlist_node *h) +static inline void +list_move_tail(struct list_head *entry, struct list_head *head) { - return !h->pprev; + _list_del(entry); + list_add_tail(entry, head); } -static inline int hlist_empty(const struct hlist_head *h) +static inline void +_list_splice(const struct list_head *list, struct list_head *prev, + struct list_head *next) { - return !h->first; -} + struct list_head *first; + struct list_head *last; -static inline void __hlist_del(struct hlist_node *n) -{ - struct hlist_node *next = n->next; - struct hlist_node **pprev = n->pprev; - *pprev = next; - if (next) - next->pprev = pprev; -} + if (list_empty(list)) + return; -static inline void hlist_del(struct hlist_node *n) -{ - __hlist_del(n); - n->next = NULL; - n->pprev = NULL; + first = list->next; + last = list->prev; + first->prev = prev; + prev->next = first; + last->next = next; + next->prev = last; } -static inline void hlist_del_init(struct hlist_node *n) +static inline void +list_splice(const struct list_head *list, struct list_head *head) { - if (!hlist_unhashed(n)) { - __hlist_del(n); - INIT_HLIST_NODE(n); - } + _list_splice(list, head, head->next); } - -static inline void hlist_add_head(struct hlist_node *n, struct hlist_head *h) +static inline void +list_splice_tail(struct list_head *list, struct list_head *head) { - struct hlist_node *first = h->first; - n->next = first; - if (first) - first->pprev = &n->next; - h->first = n; - n->pprev = &h->first; + _list_splice(list, head->prev, head); } - -/* next must be != NULL */ -static inline void hlist_add_before(struct hlist_node *n, - struct hlist_node *next) +static inline void +list_splice_init(struct list_head *list, struct list_head *head) { - n->pprev = next->pprev; - n->next = next; - next->pprev = &n->next; - *(n->pprev) = n; + _list_splice(list, head, head->next); + INIT_LIST_HEAD(list); } -static inline void hlist_add_after(struct hlist_node *n, - struct hlist_node *next) +static inline void +list_splice_tail_init(struct list_head *list, struct list_head *head) { - next->next = n->next; - n->next = next; - next->pprev = &n->next; - - if(next->next) - next->next->pprev = &next->next; + _list_splice(list, head->prev, head); + INIT_LIST_HEAD(list); } -#define hlist_entry(ptr, type, member) container_of(ptr,type,member) - -#define hlist_for_each(pos, head) \ - for (pos = (head)->first; pos; pos = pos->next) - -#define hlist_for_each_safe(pos, n, head) \ - for (pos = (head)->first; pos; pos = n) - -/** - * hlist_for_each_entry - iterate over list of given type - * @tpos: the type * to use as a loop cursor. - * @pos: the &struct hlist_node to use as a loop cursor. - * @head: the head for your list. - * @member: the name of the hlist_node within the struct. - */ -#define hlist_for_each_entry(tpos, pos, head, member) \ - for (pos = (head)->first; pos && \ - ({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \ - pos = pos->next) - -/** - * hlist_for_each_entry_continue - iterate over a hlist continuing after current point - * @tpos: the type * to use as a loop cursor. - * @pos: the &struct hlist_node to use as a loop cursor. - * @member: the name of the hlist_node within the struct. - */ -#define hlist_for_each_entry_continue(tpos, pos, member) \ - for (pos = (pos)->next; pos && \ - ({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \ - pos = pos->next) - -/** - * hlist_for_each_entry_from - iterate over a hlist continuing from current point - * @tpos: the type * to use as a loop cursor. - * @pos: the &struct hlist_node to use as a loop cursor. - * @member: the name of the hlist_node within the struct. - */ -#define hlist_for_each_entry_from(tpos, pos, member) \ - for (; pos && \ - ({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \ - pos = pos->next) - -/** - * hlist_for_each_entry_safe - iterate over list of given type safe against removal of list entry - * @tpos: the type * to use as a loop cursor. - * @pos: the &struct hlist_node to use as a loop cursor. - * @n: another &struct hlist_node to use as temporary storage - * @head: the head for your list. - * @member: the name of the hlist_node within the struct. - */ -#define hlist_for_each_entry_safe(tpos, pos, n, head, member) \ - for (pos = (head)->first; \ - pos && ({ n = pos->next; 1; }) && \ - ({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \ - pos = n) - -#endif +#endif /* _LINUX_LIST_H_ */