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/*
 * Descending-priority-sorted double-linked list
 *
 * (C) 2002-2003 Intel Corp
 * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>.
 *
 * 2001-2005 (c) MontaVista Software, Inc.
 * Daniel Walker <dwalker@mvista.com>
 *
 * (C) 2005 Thomas Gleixner <tglx@linutronix.de>
 *
 * Simplifications of the original code by
 * Oleg Nesterov <oleg@tv-sign.ru>
 *
 * Licensed under the FSF's GNU Public License v2 or later.
 *
 * Based on simple lists (include/linux/list.h).
 *
 * This is a priority-sorted list of nodes; each node has a
 * priority from INT_MIN (highest) to INT_MAX (lowest).
 *
 * Addition is O(K), removal is O(1), change of priority of a node is
 * O(K) and K is the number of RT priority levels used in the system.
 * (1 <= K <= 99)
 *
 * This list is really a list of lists:
 *
 *  - The tier 1 list is the prio_list, different priority nodes.
 *
 *  - The tier 2 list is the node_list, serialized nodes.
 *
 * Simple ASCII art explanation:
 *
 * pl:prio_list (only for plist_node)
 * nl:node_list
 *   HEAD|             NODE(S)
 *       |
 *       ||------------------------------------|
 *       ||->|pl|<->|pl|<--------------->|pl|<-|
 *       |   |10|   |21|   |21|   |21|   |40|   (prio)
 *       |   |  |   |  |   |  |   |  |   |  |
 *       |   |  |   |  |   |  |   |  |   |  |
 * |->|nl|<->|nl|<->|nl|<->|nl|<->|nl|<->|nl|<-|
 * |-------------------------------------------|
 *
 * The nodes on the prio_list list are sorted by priority to simplify
 * the insertion of new nodes. There are no nodes with duplicate
 * priorites on the list.
 *
 * The nodes on the node_list are ordered by priority and can contain
 * entries which have the same priority. Those entries are ordered
 * FIFO
 *
 * Addition means: look for the prio_list node in the prio_list
 * for the priority of the node and insert it before the node_list
 * entry of the next prio_list node. If it is the first node of
 * that priority, add it to the prio_list in the right position and
 * insert it into the serialized node_list list
 *
 * Removal means remove it from the node_list and remove it from
 * the prio_list if the node_list list_head is non empty. In case
 * of removal from the prio_list it must be checked whether other
 * entries of the same priority are on the list or not. If there
 * is another entry of the same priority then this entry has to
 * replace the removed entry on the prio_list. If the entry which
 * is removed is the only entry of this priority then a simple
 * remove from both list is sufficient.
 *
 * INT_MIN is the highest priority, 0 is the medium highest, INT_MAX
 * is lowest priority.
 *
 * No locking is done, up to the caller.
 *
 */
#ifndef _LINUX_PLIST_H_
#define _LINUX_PLIST_H_

#include <linux/kernel.h>
#include <linux/list.h>

struct plist_head {
	struct list_head node_list;
};

struct plist_node {
	int			prio;
	struct list_head	prio_list;
	struct list_head	node_list;
};

/**
 * PLIST_HEAD_INIT - static struct plist_head initializer
 * @head:	struct plist_head variable name
 */
#define PLIST_HEAD_INIT(head)				\
{							\
	.node_list = LIST_HEAD_INIT((head).node_list)	\
}

/**
 * PLIST_HEAD - declare and init plist_head
 * @head:	name for struct plist_head variable
 */
#define PLIST_HEAD(head) \
	struct plist_head head = PLIST_HEAD_INIT(head)

/**
 * PLIST_NODE_INIT - static struct plist_node initializer
 * @node:	struct plist_node variable name
 * @__prio:	initial node priority
 */
#define PLIST_NODE_INIT(node, __prio)			\
{							\
	.prio  = (__prio),				\
	.prio_list = LIST_HEAD_INIT((node).prio_list),	\
	.node_list = LIST_HEAD_INIT((node).node_list),	\
}

/**
 * plist_head_init - dynamic struct plist_head initializer
 * @head:	&struct plist_head pointer
 */
static inline void
plist_head_init(struct plist_head *head)
{
	INIT_LIST_HEAD(&head->node_list);
}

/**
 * plist_node_init - Dynamic struct plist_node initializer
 * @node:	&struct plist_node pointer
 * @prio:	initial node priority
 */
static inline void plist_node_init(struct plist_node *node, int prio)
{
	node->prio = prio;
	INIT_LIST_HEAD(&node->prio_list);
	INIT_LIST_HEAD(&node->node_list);
}

extern void plist_add(struct plist_node *node, struct plist_head *head);
extern void plist_del(struct plist_node *node, struct plist_head *head);

extern void plist_requeue(struct plist_node *node, struct plist_head *head);

/**
 * plist_for_each - iterate over the plist
 * @pos:	the type * to use as a loop counter
 * @head:	the head for your list
 */
#define plist_for_each(pos, head)	\
	 list_for_each_entry(pos, &(head)->node_list, node_list)

/**
 * plist_for_each_continue - continue iteration over the plist
 * @pos:	the type * to use as a loop cursor
 * @head:	the head for your list
 *
 * Continue to iterate over plist, continuing after the current position.
 */
#define plist_for_each_continue(pos, head)	\
	 list_for_each_entry_continue(pos, &(head)->node_list, node_list)

/**
 * plist_for_each_safe - iterate safely over a plist of given type
 * @pos:	the type * to use as a loop counter
 * @n:	another type * to use as temporary storage
 * @head:	the head for your list
 *
 * Iterate over a plist of given type, safe against removal of list entry.
 */
#define plist_for_each_safe(pos, n, head)	\
	 list_for_each_entry_safe(pos, n, &(head)->node_list, node_list)

/**
 * plist_for_each_entry	- iterate over list of given type
 * @pos:	the type * to use as a loop counter
 * @head:	the head for your list
 * @mem:	the name of the list_head within the struct
 */
#define plist_for_each_entry(pos, head, mem)	\
	 list_for_each_entry(pos, &(head)->node_list, mem.node_list)

/**
 * plist_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
 * @m:		the name of the list_head within the struct
 *
 * Continue to iterate over list of given type, continuing after
 * the current position.
 */
#define plist_for_each_entry_continue(pos, head, m)	\
	list_for_each_entry_continue(pos, &(head)->node_list, m.node_list)

/**
 * plist_for_each_entry_safe - iterate safely over list of given type
 * @pos:	the type * to use as a loop counter
 * @n:		another type * to use as temporary storage
 * @head:	the head for your list
 * @m:		the name of the list_head within the struct
 *
 * Iterate over list of given type, safe against removal of list entry.
 */
#define plist_for_each_entry_safe(pos, n, head, m)	\
	list_for_each_entry_safe(pos, n, &(head)->node_list, m.node_list)

/**
 * plist_head_empty - return !0 if a plist_head is empty
 * @head:	&struct plist_head pointer
 */
static inline int plist_head_empty(const struct plist_head *head)
{
	return list_empty(&head->node_list);
}

/**
 * plist_node_empty - return !0 if plist_node is not on a list
 * @node:	&struct plist_node pointer
 */
static inline int plist_node_empty(const struct plist_node *node)
{
	return list_empty(&node->node_list);
}

/* All functions below assume the plist_head is not empty. */

/**
 * plist_first_entry - get the struct for the first entry
 * @head:	the &struct plist_head pointer
 * @type:	the type of the struct this is embedded in
 * @member:	the name of the list_head within the struct
 */
#ifdef CONFIG_DEBUG_PI_LIST
# define plist_first_entry(head, type, member)	\
({ \
	WARN_ON(plist_head_empty(head)); \
	container_of(plist_first(head), type, member); \
})
#else
# define plist_first_entry(head, type, member)	\
	container_of(plist_first(head), type, member)
#endif

/**
 * plist_last_entry - get the struct for the last entry
 * @head:	the &struct plist_head pointer
 * @type:	the type of the struct this is embedded in
 * @member:	the name of the list_head within the struct
 */
#ifdef CONFIG_DEBUG_PI_LIST
# define plist_last_entry(head, type, member)	\
({ \
	WARN_ON(plist_head_empty(head)); \
	container_of(plist_last(head), type, member); \
})
#else
# define plist_last_entry(head, type, member)	\
	container_of(plist_last(head), type, member)
#endif

/**
 * plist_next - get the next entry in list
 * @pos:	the type * to cursor
 */
#define plist_next(pos) \
	list_next_entry(pos, node_list)

/**
 * plist_prev - get the prev entry in list
 * @pos:	the type * to cursor
 */
#define plist_prev(pos) \
	list_prev_entry(pos, node_list)

/**
 * plist_first - return the first node (and thus, highest priority)
 * @head:	the &struct plist_head pointer
 *
 * Assumes the plist is _not_ empty.
 */
static inline struct plist_node *plist_first(const struct plist_head *head)
{
	return list_entry(head->node_list.next,
			  struct plist_node, node_list);
}

/**
 * plist_last - return the last node (and thus, lowest priority)
 * @head:	the &struct plist_head pointer
 *
 * Assumes the plist is _not_ empty.
 */
static inline struct plist_node *plist_last(const struct plist_head *head)
{
	return list_entry(head->node_list.prev,
			  struct plist_node, node_list);
}

#endif
new, struct list_head *head) { __list_add(new, head->prev, 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) { next->prev = prev; prev->next = 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. */ #ifndef CONFIG_DEBUG_LIST static inline void __list_del_entry(struct list_head *entry) { __list_del(entry->prev, entry->next); } static inline void list_del(struct list_head *entry) { __list_del(entry->prev, entry->next); entry->next = LIST_POISON1; entry->prev = LIST_POISON2; } #else extern void __list_del_entry(struct list_head *entry); extern void list_del(struct list_head *entry); #endif /** * 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) { 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); } /** * 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) { __list_del_entry(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_entry(list); list_add(list, head); } /** * 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_entry(list); list_add_tail(list, head); } /** * 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; } /** * 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; } /** * 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); } /** * list_rotate_left - rotate the list to the left * @head: the head of the list */ static inline void list_rotate_left(struct list_head *head) { struct list_head *first; if (!list_empty(head)) { first = head->next; list_move_tail(first, head); } } /** * list_is_singular - tests whether a list has just one entry. * @head: the list to test. */ static inline int list_is_singular(const struct list_head *head) { return !list_empty(head) && (head->next == head->prev); } static inline void __list_cut_position(struct list_head *list, struct list_head *head, struct list_head *entry) { struct list_head *new_first = entry->next; list->next = head->next; list->next->prev = list; list->prev = entry; entry->next = list; head->next = new_first; new_first->prev = head; } /** * list_cut_position - cut a list into two * @list: a new list to add all removed entries * @head: a list with entries * @entry: an entry within head, could be the head itself * and if so we won't cut the list * * This helper moves the initial part of @head, up to and * including @entry, from @head to @list. You should * pass on @entry an element you know is on @head. @list * should be an empty list or a list you do not care about * losing its data. * */ static inline void list_cut_position(struct list_head *list, struct list_head *head, struct list_head *entry) { if (list_empty(head)) return; if (list_is_singular(head) && (head->next != entry && head != entry)) return; if (entry == head) INIT_LIST_HEAD(list); else __list_cut_position(list, head, entry); } static inline void __list_splice(const struct list_head *list, struct list_head *prev, struct list_head *next) { struct list_head *first = list->next; struct list_head *last = list->prev; first->prev = prev; prev->next = first; last->next = next; next->prev = last; } /** * list_splice - join two lists, this is designed for stacks * @list: the new list to add. * @head: the place to add it in the first list. */ static inline void list_splice(const struct list_head *list, struct list_head *head) { if (!list_empty(list)) __list_splice(list, head, head->next); } /** * list_splice_tail - join two lists, each list being a queue * @list: the new list to add. * @head: the place to add it in the first list. */ static inline void list_splice_tail(struct list_head *list, struct list_head *head) { if (!list_empty(list)) __list_splice(list, head->prev, head); } /** * 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) { if (!list_empty(list)) { __list_splice(list, head, head->next); INIT_LIST_HEAD(list); } } /** * list_splice_tail_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. * * Each of the lists is a queue. * The list at @list is reinitialised */ static inline void list_splice_tail_init(struct list_head *list, struct list_head *head) { if (!list_empty(list)) { __list_splice(list, head->prev, head); INIT_LIST_HEAD(list); } } /** * 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_head 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_head 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_last_entry - get the last 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_head within the struct. * * Note, that list is expected to be not empty. */ #define list_last_entry(ptr, type, member) \ list_entry((ptr)->prev, type, member) /** * list_first_entry_or_null - 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_head within the struct. * * Note that if the list is empty, it returns NULL. */ #define list_first_entry_or_null(ptr, type, member) \ (!list_empty(ptr) ? list_first_entry(ptr, type, member) : NULL) /** * list_next_entry - get the next element in list * @pos: the type * to cursor * @member: the name of the list_head within the struct. */ #define list_next_entry(pos, member) \ list_entry((pos)->member.next, typeof(*(pos)), member) /** * list_prev_entry - get the prev element in list * @pos: the type * to cursor * @member: the name of the list_head within the struct. */ #define list_prev_entry(pos, member) \ list_entry((pos)->member.prev, typeof(*(pos)), 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_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_head within the struct. */ #define list_for_each_entry(pos, head, member) \ for (pos = list_first_entry(head, typeof(*pos), member); \ &pos->member != (head); \ pos = list_next_entry(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_head within the struct. */ #define list_for_each_entry_reverse(pos, head, member) \ for (pos = list_last_entry(head, typeof(*pos), member); \ &pos->member != (head); \ pos = list_prev_entry(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_head 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_head 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_next_entry(pos, member); \ &pos->member != (head); \ pos = list_next_entry(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_head 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_prev_entry(pos, member); \ &pos->member != (head); \ pos = list_prev_entry(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_head 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_next_entry(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_head within the struct. */ #define list_for_each_entry_safe(pos, n, head, member) \ for (pos = list_first_entry(head, typeof(*pos), member), \ n = list_next_entry(pos, member); \ &pos->member != (head); \ pos = n, n = list_next_entry(n, member)) /** * list_for_each_entry_safe_continue - continue list iteration safe against removal * @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_head 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_next_entry(pos, member), \ n = list_next_entry(pos, member); \ &pos->member != (head); \ pos = n, n = list_next_entry(n, member)) /** * list_for_each_entry_safe_from - iterate over list from current point safe against removal * @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_head 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_next_entry(pos, member); \ &pos->member != (head); \ pos = n, n = list_next_entry(n, member)) /** * list_for_each_entry_safe_reverse - iterate backwards over list safe against removal * @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_head 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_last_entry(head, typeof(*pos), member), \ n = list_prev_entry(pos, member); \ &pos->member != (head); \ pos = n, n = list_prev_entry(n, member)) /** * list_safe_reset_next - reset a stale list_for_each_entry_safe loop * @pos: the loop cursor used in the list_for_each_entry_safe loop * @n: temporary storage used in list_for_each_entry_safe * @member: the name of the list_head within the struct. * * list_safe_reset_next is not safe to use in general if the list may be * modified concurrently (eg. the lock is dropped in the loop body). An * exception to this is if the cursor element (pos) is pinned in the list, * and list_safe_reset_next is called after re-taking the lock and before * completing the current iteration of the loop body. */ #define list_safe_reset_next(pos, n, member) \ n = list_next_entry(pos, 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). */ #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) { h->next = NULL; h->pprev = NULL; } static inline int hlist_unhashed(const struct hlist_node *h) { return !h->pprev; } static inline int hlist_empty(const struct hlist_head *h) { return !h->first; } 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; } static inline void hlist_del(struct hlist_node *n) { __hlist_del(n); n->next = LIST_POISON1; n->pprev = LIST_POISON2; } static inline void hlist_del_init(struct hlist_node *n) { if (!hlist_unhashed(n)) { __hlist_del(n); INIT_HLIST_NODE(n); } } static inline void hlist_add_head(struct hlist_node *n, struct hlist_head *h) { struct hlist_node *first = h->first; n->next = first; if (first) first->pprev = &n->next; h->first = n; n->pprev = &h->first; } /* next must be != NULL */ static inline void hlist_add_before(struct hlist_node *n, struct hlist_node *next) { n->pprev = next->pprev; n->next = next; next->pprev = &n->next; *(n->pprev) = n; } static inline void hlist_add_behind(struct hlist_node *n, struct hlist_node *prev) { n->next = prev->next; prev->next = n; n->pprev = &prev->next; if (n->next) n->next->pprev = &n->next; } /* after that we'll appear to be on some hlist and hlist_del will work */ static inline void hlist_add_fake(struct hlist_node *n) { n->pprev = &n->next; } /* * Move a list from one list head to another. Fixup the pprev * reference of the first entry if it exists. */ static inline void hlist_move_list(struct hlist_head *old, struct hlist_head *new) { new->first = old->first; if (new->first) new->first->pprev = &new->first; old->first = NULL; } #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 && ({ n = pos->next; 1; }); \ pos = n) #define hlist_entry_safe(ptr, type, member) \ ({ typeof(ptr) ____ptr = (ptr); \ ____ptr ? hlist_entry(____ptr, type, member) : NULL; \ }) /** * hlist_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 hlist_node within the struct. */ #define hlist_for_each_entry(pos, head, member) \ for (pos = hlist_entry_safe((head)->first, typeof(*(pos)), member);\ pos; \ pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member)) /** * hlist_for_each_entry_continue - iterate over a hlist continuing after current point * @pos: the type * to use as a loop cursor. * @member: the name of the hlist_node within the struct. */ #define hlist_for_each_entry_continue(pos, member) \ for (pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member);\ pos; \ pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member)) /** * hlist_for_each_entry_from - iterate over a hlist continuing from current point * @pos: the type * to use as a loop cursor. * @member: the name of the hlist_node within the struct. */ #define hlist_for_each_entry_from(pos, member) \ for (; pos; \ pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member)) /** * hlist_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 &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(pos, n, head, member) \ for (pos = hlist_entry_safe((head)->first, typeof(*pos), member);\ pos && ({ n = pos->member.next; 1; }); \ pos = hlist_entry_safe(n, typeof(*pos), member)) #endif