1 /* 2 * mr_sas_list.h: header for mr_sas 3 * 4 * Solaris MegaRAID driver for SAS2.0 controllers 5 * Copyright (c) 2008-2009, LSI Logic Corporation. 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 are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright notice, 12 * this list of conditions and the following disclaimer. 13 * 14 * 2. Redistributions in binary form must reproduce the above copyright notice, 15 * this list of conditions and the following disclaimer in the documentation 16 * and/or other materials provided with the distribution. 17 * 18 * 3. Neither the name of the author nor the names of its contributors may be 19 * used to endorse or promote products derived from this software without 20 * specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 23 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 25 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 26 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 27 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 28 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 29 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 30 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 31 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 32 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH 33 * DAMAGE. 34 */ 35 36 /* 37 * Copyright 2009 Sun Microsystems, Inc. All rights reserved. 38 * Use is subject to license terms. 39 */ 40 41 #ifndef _MR_SAS_LIST_H_ 42 #define _MR_SAS_LIST_H_ 43 44 #ifdef __cplusplus 45 extern "C" { 46 #endif 47 48 /* 49 * Simple doubly linked list implementation. 50 * 51 * Some of the internal functions ("__xxx") are useful when 52 * manipulating whole lists rather than single entries, as 53 * sometimes we already know the next/prev entries and we can 54 * generate better code by using them directly rather than 55 * using the generic single-entry routines. 56 */ 57 58 struct mlist_head { 59 struct mlist_head *next, *prev; 60 }; 61 62 typedef struct mlist_head mlist_t; 63 64 #define LIST_HEAD_INIT(name) { &(name), &(name) } 65 66 #define LIST_HEAD(name) \ 67 struct mlist_head name = LIST_HEAD_INIT(name) 68 69 #define INIT_LIST_HEAD(ptr) { \ 70 (ptr)->next = (ptr); (ptr)->prev = (ptr); \ 71 } 72 73 #ifndef KMDB_MODULE 74 /* 75 * Insert a new entry between two known consecutive entries. 76 * 77 * This is only for internal list manipulation where we know 78 * the prev/next entries already! 79 */ 80 static void __list_add(struct mlist_head *new, 81 struct mlist_head *prev, 82 struct mlist_head *next) 83 { 84 next->prev = new; 85 new->next = next; 86 new->prev = prev; 87 prev->next = new; 88 } 89 90 91 /* 92 * mlist_add - add a new entry 93 * @new: new entry to be added 94 * @head: list head to add it after 95 * 96 * Insert a new entry after the specified head. 97 * This is good for implementing stacks. 98 */ 99 static void mlist_add(struct mlist_head *new, struct mlist_head *head) 100 { 101 __list_add(new, head, head->next); 102 } 103 104 105 /* 106 * mlist_add_tail - add a new entry 107 * @new: new entry to be added 108 * @head: list head to add it before 109 * 110 * Insert a new entry before the specified head. 111 * This is useful for implementing queues. 112 */ 113 static void mlist_add_tail(struct mlist_head *new, struct mlist_head *head) 114 { 115 __list_add(new, head->prev, head); 116 } 117 118 119 120 /* 121 * Delete a list entry by making the prev/next entries 122 * point to each other. 123 * 124 * This is only for internal list manipulation where we know 125 * the prev/next entries already! 126 */ 127 static void __list_del(struct mlist_head *prev, 128 struct mlist_head *next) 129 { 130 next->prev = prev; 131 prev->next = next; 132 } 133 134 135 /* 136 * mlist_del_init - deletes entry from list and reinitialize it. 137 * @entry: the element to delete from the list. 138 */ 139 static void mlist_del_init(struct mlist_head *entry) 140 { 141 __list_del(entry->prev, entry->next); 142 INIT_LIST_HEAD(entry); 143 } 144 145 146 /* 147 * mlist_empty - tests whether a list is empty 148 * @head: the list to test. 149 */ 150 static int mlist_empty(struct mlist_head *head) 151 { 152 return (head->next == head); 153 } 154 155 156 /* 157 * mlist_splice - join two lists 158 * @list: the new list to add. 159 * @head: the place to add it in the first list. 160 */ 161 static void mlist_splice(struct mlist_head *list, struct mlist_head *head) 162 { 163 struct mlist_head *first = list->next; 164 165 if (first != list) { 166 struct mlist_head *last = list->prev; 167 struct mlist_head *at = head->next; 168 169 first->prev = head; 170 head->next = first; 171 172 last->next = at; 173 at->prev = last; 174 } 175 } 176 #endif /* KMDB_MODULE */ 177 178 /* 179 * mlist_entry - get the struct for this entry 180 * @ptr: the &struct mlist_head pointer. 181 * @type: the type of the struct this is embedded in. 182 * @member: the name of the list_struct within the struct. 183 */ 184 #define mlist_entry(ptr, type, member) \ 185 ((type *)((size_t)(ptr) - offsetof(type, member))) 186 187 188 /* 189 * mlist_for_each - iterate over a list 190 * @pos: the &struct mlist_head to use as a loop counter. 191 * @head: the head for your list. 192 */ 193 #define mlist_for_each(pos, head) \ 194 for (pos = (head)->next, prefetch(pos->next); pos != (head); \ 195 pos = pos->next, prefetch(pos->next)) 196 197 198 /* 199 * mlist_for_each_safe - iterate over a list safe against removal of list entry 200 * @pos: the &struct mlist_head to use as a loop counter. 201 * @n: another &struct mlist_head to use as temporary storage 202 * @head: the head for your list. 203 */ 204 #define mlist_for_each_safe(pos, n, head) \ 205 for (pos = (head)->next, n = pos->next; pos != (head); \ 206 pos = n, n = pos->next) 207 208 #ifdef __cplusplus 209 } 210 #endif 211 212 #endif /* _MR_SAS_LIST_H_ */ 213