list.h revision 6029a2d88c01674debfd7c2e16c941a97302b739
/*
* list.h: header for mega_sas
*
* Solaris MegaRAID driver for SAS controllers
* Copyright (c) 2004-2008, LSI Logic Corporation.
* 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,
* 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.
*
* 3. Neither the name of the author nor the names of its contributors may be
* used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "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
* COPYRIGHT OWNER OR CONTRIBUTORS 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.
*/
/*
* Copyright 2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#ifndef _LIST_H_
#define _LIST_H_
#pragma ident "%Z%%M% %I% %E% SMI"
#ifdef __cplusplus
extern "C" {
#endif
/*
* 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.
*/
struct mlist_head {
struct mlist_head *next, *prev;
};
typedef struct mlist_head mlist_t;
#define LIST_HEAD_INIT(name) { &(name), &(name) }
#define LIST_HEAD(name) \
struct mlist_head name = LIST_HEAD_INIT(name)
#define INIT_LIST_HEAD(ptr) { \
(ptr)->next = (ptr); (ptr)->prev = (ptr); \
}
/*
* 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 void __list_add(struct mlist_head *new,
struct mlist_head *prev,
struct mlist_head *next)
{
next->prev = new;
new->next = next;
new->prev = prev;
prev->next = new;
}
/*
* mlist_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 void mlist_add(struct mlist_head *new, struct mlist_head *head)
{
__list_add(new, head, head->next);
}
/*
* mlist_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 void mlist_add_tail(struct mlist_head *new, struct mlist_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 void __list_del(struct mlist_head *prev,
struct mlist_head *next)
{
next->prev = prev;
prev->next = next;
}
/*
* mlist_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.
*/
/* LINTED E_STATIC_UNUSED */
static void mlist_del(struct mlist_head *entry)
{
__list_del(entry->prev, entry->next);
entry->next = entry->prev = 0;
}
/*
* mlist_del_init - deletes entry from list and reinitialize it.
* @entry: the element to delete from the list.
*/
static void mlist_del_init(struct mlist_head *entry)
{
__list_del(entry->prev, entry->next);
INIT_LIST_HEAD(entry);
}
/*
* mlist_empty - tests whether a list is empty
* @head: the list to test.
*/
static int mlist_empty(struct mlist_head *head)
{
return (head->next == head);
}
/*
* mlist_splice - join two lists
* @list: the new list to add.
* @head: the place to add it in the first list.
*/
static void mlist_splice(struct mlist_head *list, struct mlist_head *head)
{
struct mlist_head *first = list->next;
if (first != list) {
struct mlist_head *last = list->prev;
struct mlist_head *at = head->next;
first->prev = head;
head->next = first;
last->next = at;
at->prev = last;
}
}
/* TODO: set this */
#if 0
#pragma inline(list_add, list_add_tail, __list_del, list_del,
list_del_init, list_empty, list_splice)
#endif
/*
* mlist_entry - get the struct for this entry
* @ptr: the &struct mlist_head pointer.
* @type: the type of the struct this is embedded in.
* @member: the name of the list_struct within the struct.
*/
#define mlist_entry(ptr, type, member) \
((type *)((char *)(ptr)-(unsigned long)(&((type *)0)->member)))
/*
* mlist_for_each - iterate over a list
* @pos: the &struct mlist_head to use as a loop counter.
* @head: the head for your list.
*/
#define mlist_for_each(pos, head) \
for (pos = (head)->next, prefetch(pos->next); pos != (head); \
pos = pos->next, prefetch(pos->next))
/*
* mlist_for_each_safe - iterate over a list safe against removal of list entry
* @pos: the &struct mlist_head to use as a loop counter.
* @n: another &struct mlist_head to use as temporary storage
* @head: the head for your list.
*/
#define mlist_for_each_safe(pos, n, head) \
for (pos = (head)->next, n = pos->next; pos != (head); \
pos = n, n = pos->next)
#ifdef __cplusplus
}
#endif
#endif /* _LIST_H_ */