freebsd-nq/sys/dev/isci/scil/sci_fast_list.h
Pedro F. Giffuni 718cf2ccb9 sys/dev: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
2017-11-27 14:52:40 +00:00

342 lines
12 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause OR GPL-2.0
*
* This file is provided under a dual BSD/GPLv2 license. When using or
* redistributing this file, you may do so under either license.
*
* GPL LICENSE SUMMARY
*
* Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
* The full GNU General Public License is included in this distribution
* in the file called LICENSE.GPL.
*
* BSD LICENSE
*
* Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * 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 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.
*
* $FreeBSD$
*/
#ifndef _SCI_FAST_LIST_HEADER_
#define _SCI_FAST_LIST_HEADER_
/**
* @file
*
* @brief Header file that contains basic Linked List manipulation macros.
* These macros implement a double linked list (SCI_FAST_LIST_T) that is
* circular in nature. This means that the next and prev pointers for
* an empty queue head always the address of the queue head
* SCI_FAST_LIST_T. Likewise an element that has been removed from
* a queue will have its next and prev pointer set to the address of
* the SCI_FAST_LIST_T found in the structure just removed from the
* queue. Pointers in this implementation never == NULL.
*
* Definitions:
* - anchor : This is the list container and has a
* pointer to both the head and tail of the
* list elements
* - element: This is the list element not the actual
* object but the list element which has a
* pointer to the object.
*/
//******************************************************************************
//*
//* P U B L I C M E T H O D S
//*
//******************************************************************************
/**
* Initialize the double linked list anchor. The other macros require the list
* anchor to be set up using this macro.
*/
#define sci_fast_list_init(anchor) \
{ \
(anchor)->list_head = NULL; \
(anchor)->list_tail = NULL; \
(anchor)->element_count = 0; \
}
/**
* Initialize the sci_fast_list_element to point to its owning object
*/
#define sci_fast_list_element_init(list_object, element) \
{ \
(element)->object = (list_object); \
(element)->next = (element)->prev = NULL; \
(element)->owning_list = NULL; \
}
/**
* See if there is anything on the list by checking the list anchor.
*/
#define sci_fast_list_is_empty(anchor) ((anchor)->list_head == NULL)
/**
* Return a pointer to the element at the head of the sci_fast_list. The
* item is NOT removed from the list.
*
* NOTE: This macro will always return a value, even if the list is empty.
* You must insure the list is not empty or use Dlist_safeGetHead.
*
* element - A pointer into which to save the address of the structure
* containing the SCI_FAST_LIST at the list head.
*/
#define sci_fast_list_get_head(anchor) \
((anchor)->list_head == NULL ? NULL: (anchor)->list_head->object)
/**
* Return a pointer to the element at the tail of the sci_fast_list. The item
* is NOT removed from the list.
*
* NOTE: This macro will always return a value, even if the list is empty.
* You must insure the list is not empty or use Dlist_safeGetHead.
*
* element - A pointer into which to save the address of the structure
* containing the SCI_FAST_LIST at the list head.
*/
#define sci_fast_list_get_tail(anchor) \
((anchor)->list_tail == NULL ? NULL: (anchor)->list_head->object)
/**
* This method will get the next dListField in the SCI_FAST_LIST. This method
* returns a pointer to a SCI_FAST_LIST object.
*/
#define sci_fast_list_get_next(element) ((element)->next)
/**
* This method will get the prev dListField in the SCI_FAST_LIST. This method
* returns a pointer to a SCI_FAST_LIST object.
*/
#define sci_fast_list_get_prev(element) ((element)->prev)
/**
* This method returns the object that is represented by this
* sci_fast_list_element
*/
#define sci_fast_list_get_object(element) ((element)->object)
/**
* This method will determine if the supplied dListField is on a SCI_FAST_LIST.
* If the element has only one dListField but can be on more than one list,
* this will only tell you that it is on one of them. If the element has
* multiple dListFields and can exist on multiple lists at the same time, this
* macro can tell you exactly which list it is on.
*/
#define sci_fast_list_is_on_a_list(element) ((element)->owning_list != NULL)
/**
* This method will determine if the supplied dListFieldName is on the given
* specified list? If the element can be on more than one list, this
* allows you to determine exactly which list it is on. Performs a linear
* search through the list.
* result - BOOL_T that will contain the result of the search.
* TRUE - item is on the list described by head.
* FALSE - item is not on the list.
*/
#define sci_fast_list_is_on_this_list(anchor, element) \
((element)->owning_list == (anchor))
//******************************************************************************
//*
//* T Y P E S
//*
//******************************************************************************
/**
* @struct SCI_FAST_LIST
*
* @brief the list owner or list anchor for a set of SCI_FAST_LIST
* elements.
*/
typedef struct SCI_FAST_LIST
{
struct SCI_FAST_LIST_ELEMENT *list_head;
struct SCI_FAST_LIST_ELEMENT *list_tail;
int element_count;
} SCI_FAST_LIST_T;
/**
* @struct SCI_FAST_LIST_ELEMENT
*
* @brief This structure defines what a doubly linked list element contains.
*/
typedef struct SCI_FAST_LIST_ELEMENT
{
struct SCI_FAST_LIST_ELEMENT *next;
struct SCI_FAST_LIST_ELEMENT *prev;
struct SCI_FAST_LIST *owning_list;
void *object;
} SCI_FAST_LIST_ELEMENT_T;
/**
* Insert an element to be the new head of the list hanging off of the list
* anchor. An empty list has the list anchor pointing to itself.
* dListAnchor - The name of the SCI_FAST_LIST_T element that is the anchor
* of the queue.
* dListFieldBeingInserted - The SCI_FAST_LIST_T field in the data structure
* being queued. This SCI_FAST_LIST will become
* the new list head.
*/
INLINE
static void sci_fast_list_insert_head(
SCI_FAST_LIST_T *anchor,
SCI_FAST_LIST_ELEMENT_T *element
)
{
element->owning_list = anchor;
element->prev = NULL;
if ( anchor->list_head == NULL )
anchor->list_tail = element;
else
anchor->list_head->prev = element;
element->next = anchor->list_head;
anchor->list_head = element;
anchor->element_count++;
}
/**
* Insert an element at the tail of the list. Since the list is circular we
* can add the element at the tail through use the list anchors previous
* pointer.
* dListAnchor - The name of the SCI_FAST_LIST_T element that is the anchor
* of the queue.
* dListFieldBeingInserted - The SCI_FAST_LIST_T field in the data structure
* being queued. This SCI_FAST_LIST will become
* the new list head.
*/
INLINE
static void sci_fast_list_insert_tail(
SCI_FAST_LIST_T *anchor,
SCI_FAST_LIST_ELEMENT_T *element
)
{
element->owning_list = anchor;
element->next = NULL;
if ( anchor->list_tail == NULL ) {
anchor->list_head = element;
} else {
anchor->list_tail->next = element;
}
element->prev = anchor->list_tail;
anchor->list_tail = element;
anchor->element_count++;
}
/**
* This method will remove a dListFieldName from the head of the list.
*
* NOTE: This macro will always return a value, even if the list is empty.
* You must insure the list is not empty or use Dlist_safeRemoveHead.
*
* element - A pointer into which to save the address of the structure
* containing the SCI_FAST_LIST at the list head.
*/
INLINE
static void *sci_fast_list_remove_head(
SCI_FAST_LIST_T *anchor
)
{
void *object = NULL;
SCI_FAST_LIST_ELEMENT_T *element;
if ( anchor->list_head != NULL )
{
element = anchor->list_head;
object = anchor->list_head->object;
anchor->list_head = anchor->list_head->next;
if ( anchor->list_head == NULL )
{
anchor->list_tail = NULL;
}
anchor->element_count--;
element->next = element->prev = NULL;
element->owning_list = NULL;
}
return object;
}
INLINE
static void *sci_fast_list_remove_tail(
SCI_FAST_LIST_T *anchor
)
{
void *object = NULL;
SCI_FAST_LIST_ELEMENT_T *element;
if ( anchor->list_tail != NULL )
{
element = anchor->list_tail;
object = element->object;
anchor->list_tail = element->prev;
if ( anchor->list_tail == NULL )
anchor->list_head = NULL;
anchor->element_count--;
element->next = element->prev = NULL;
element->owning_list = NULL;
}
return object;
}
/**
* Remove an element from anywhere in the list referenced by name.
*/
INLINE
static void sci_fast_list_remove_element(
SCI_FAST_LIST_ELEMENT_T *element
)
{
if ( element->next == NULL )
element->owning_list->list_tail = element->prev;
else
element->next->prev = element->prev;
if ( element->prev == NULL )
element->owning_list->list_head = element->next;
else
element->prev->next = element->next;
element->owning_list->element_count--;
element->next = element->prev = NULL;
element->owning_list = NULL;
}
#endif // _SCI_FAST_LIST_HEADER_