1 #ifndef _LINUX_FLIST_H 2 #define _LINUX_FLIST_H 3 4 #include <stdlib.h> 5 6 #undef offsetof 7 #ifdef __compiler_offsetof 8 #define offsetof(TYPE,MEMBER) __compiler_offsetof(TYPE,MEMBER) 9 #else 10 #define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER) 11 #endif 12 13 #define container_of(ptr, type, member) ({ \ 14 const typeof( ((type *)0)->member ) *__mptr = (ptr); \ 15 (type *)( (char *)__mptr - offsetof(type,member) );}) 16 17 /* 18 * Simple doubly linked list implementation. 19 * 20 * Some of the internal functions ("__xxx") are useful when 21 * manipulating whole lists rather than single entries, as 22 * sometimes we already know the next/prev entries and we can 23 * generate better code by using them directly rather than 24 * using the generic single-entry routines. 25 */ 26 27 struct flist_head { 28 struct flist_head *next, *prev; 29 }; 30 31 #define FLIST_HEAD_INIT(name) { &(name), &(name) } 32 33 #define FLIST_HEAD(name) \ 34 struct flist_head name = FLIST_HEAD_INIT(name) 35 36 #define INIT_FLIST_HEAD(ptr) do { \ 37 (ptr)->next = (ptr); (ptr)->prev = (ptr); \ 38 } while (0) 39 40 /* 41 * Insert a new entry between two known consecutive entries. 42 * 43 * This is only for internal list manipulation where we know 44 * the prev/next entries already! 45 */ 46 static inline void __flist_add(struct flist_head *new_entry, 47 struct flist_head *prev, 48 struct flist_head *next) 49 { 50 next->prev = new_entry; 51 new_entry->next = next; 52 new_entry->prev = prev; 53 prev->next = new_entry; 54 } 55 56 /** 57 * flist_add - add a new entry 58 * @new_entry: new entry to be added 59 * @head: list head to add it after 60 * 61 * Insert a new entry after the specified head. 62 * This is good for implementing stacks. 63 */ 64 static inline void flist_add(struct flist_head *new_entry, 65 struct flist_head *head) 66 { 67 __flist_add(new_entry, head, head->next); 68 } 69 70 static inline void flist_add_tail(struct flist_head *new_entry, 71 struct flist_head *head) 72 { 73 __flist_add(new_entry, head->prev, head); 74 } 75 76 /* 77 * Delete a list entry by making the prev/next entries 78 * point to each other. 79 * 80 * This is only for internal list manipulation where we know 81 * the prev/next entries already! 82 */ 83 static inline void __flist_del(struct flist_head *prev, 84 struct flist_head * next) 85 { 86 next->prev = prev; 87 prev->next = next; 88 } 89 90 /** 91 * flist_del - deletes entry from list. 92 * @entry: the element to delete from the list. 93 * Note: flist_empty on entry does not return true after this, the entry is 94 * in an undefined state. 95 */ 96 static inline void flist_del(struct flist_head *entry) 97 { 98 __flist_del(entry->prev, entry->next); 99 entry->next = NULL; 100 entry->prev = NULL; 101 } 102 103 /** 104 * flist_del_init - deletes entry from list and reinitialize it. 105 * @entry: the element to delete from the list. 106 */ 107 static inline void flist_del_init(struct flist_head *entry) 108 { 109 __flist_del(entry->prev, entry->next); 110 INIT_FLIST_HEAD(entry); 111 } 112 113 /** 114 * flist_empty - tests whether a list is empty 115 * @head: the list to test. 116 */ 117 static inline int flist_empty(const struct flist_head *head) 118 { 119 return head->next == head; 120 } 121 122 static inline void __flist_splice(const struct flist_head *list, 123 struct flist_head *prev, 124 struct flist_head *next) 125 { 126 struct flist_head *first = list->next; 127 struct flist_head *last = list->prev; 128 129 first->prev = prev; 130 prev->next = first; 131 132 last->next = next; 133 next->prev = last; 134 } 135 136 static inline void flist_splice(const struct flist_head *list, 137 struct flist_head *head) 138 { 139 if (!flist_empty(list)) 140 __flist_splice(list, head, head->next); 141 } 142 143 static inline void flist_splice_tail(struct flist_head *list, 144 struct flist_head *head) 145 { 146 if (!flist_empty(list)) 147 __flist_splice(list, head->prev, head); 148 } 149 150 static inline void flist_splice_tail_init(struct flist_head *list, 151 struct flist_head *head) 152 { 153 if (!flist_empty(list)) { 154 __flist_splice(list, head->prev, head); 155 INIT_FLIST_HEAD(list); 156 } 157 } 158 159 static inline void flist_splice_init(struct flist_head *list, 160 struct flist_head *head) 161 { 162 if (!flist_empty(list)) { 163 __flist_splice(list, head, head->next); 164 INIT_FLIST_HEAD(list); 165 } 166 } 167 168 /** 169 * flist_entry - get the struct for this entry 170 * @ptr: the &struct flist_head pointer. 171 * @type: the type of the struct this is embedded in. 172 * @member: the name of the flist_struct within the struct. 173 */ 174 #define flist_entry(ptr, type, member) \ 175 container_of(ptr, type, member) 176 177 #define flist_first_entry(ptr, type, member) \ 178 flist_entry((ptr)->next, type, member) 179 180 #define flist_last_entry(ptr, type, member) \ 181 flist_entry((ptr)->prev, type, member) 182 183 /** 184 * flist_for_each - iterate over a list 185 * @pos: the &struct flist_head to use as a loop counter. 186 * @head: the head for your list. 187 */ 188 #define flist_for_each(pos, head) \ 189 for (pos = (head)->next; pos != (head); pos = pos->next) 190 191 /** 192 * flist_for_each_safe - iterate over a list safe against removal of list entry 193 * @pos: the &struct flist_head to use as a loop counter. 194 * @n: another &struct flist_head to use as temporary storage 195 * @head: the head for your list. 196 */ 197 #define flist_for_each_safe(pos, n, head) \ 198 for (pos = (head)->next, n = pos->next; pos != (head); \ 199 pos = n, n = pos->next) 200 201 extern void flist_sort(void *priv, struct flist_head *head, 202 int (*cmp)(void *priv, struct flist_head *a, struct flist_head *b)); 203 204 #endif 205
