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1 | #ifndef _LINUX_LIST_H |
1 | #ifndef _LINUX_LIST_H |
2 | #define _LINUX_LIST_H |
2 | #define _LINUX_LIST_H |
3 | 3 | ||
4 | #include |
4 | #include |
5 | #include |
5 | #include |
6 | #include |
6 | #include |
7 | #include |
7 | #include |
8 | #include |
8 | #include |
9 | 9 | ||
10 | /* |
10 | /* |
11 | * Simple doubly linked list implementation. |
11 | * Simple doubly linked list implementation. |
12 | * |
12 | * |
13 | * Some of the internal functions ("__xxx") are useful when |
13 | * Some of the internal functions ("__xxx") are useful when |
14 | * manipulating whole lists rather than single entries, as |
14 | * manipulating whole lists rather than single entries, as |
15 | * sometimes we already know the next/prev entries and we can |
15 | * sometimes we already know the next/prev entries and we can |
16 | * generate better code by using them directly rather than |
16 | * generate better code by using them directly rather than |
17 | * using the generic single-entry routines. |
17 | * using the generic single-entry routines. |
18 | */ |
18 | */ |
19 | 19 | ||
20 | #define LIST_HEAD_INIT(name) { &(name), &(name) } |
20 | #define LIST_HEAD_INIT(name) { &(name), &(name) } |
21 | 21 | ||
22 | #define LIST_HEAD(name) \ |
22 | #define LIST_HEAD(name) \ |
23 | struct list_head name = LIST_HEAD_INIT(name) |
23 | struct list_head name = LIST_HEAD_INIT(name) |
24 | 24 | ||
25 | static inline void INIT_LIST_HEAD(struct list_head *list) |
25 | static inline void INIT_LIST_HEAD(struct list_head *list) |
26 | { |
26 | { |
27 | list->next = list; |
27 | WRITE_ONCE(list->next, list); |
28 | list->prev = list; |
28 | list->prev = list; |
29 | } |
29 | } |
30 | 30 | ||
31 | /* |
31 | /* |
32 | * Insert a new entry between two known consecutive entries. |
32 | * Insert a new entry between two known consecutive entries. |
33 | * |
33 | * |
34 | * This is only for internal list manipulation where we know |
34 | * This is only for internal list manipulation where we know |
35 | * the prev/next entries already! |
35 | * the prev/next entries already! |
36 | */ |
36 | */ |
37 | #ifndef CONFIG_DEBUG_LIST |
37 | #ifndef CONFIG_DEBUG_LIST |
38 | static inline void __list_add(struct list_head *new, |
38 | static inline void __list_add(struct list_head *new, |
39 | struct list_head *prev, |
39 | struct list_head *prev, |
40 | struct list_head *next) |
40 | struct list_head *next) |
41 | { |
41 | { |
42 | next->prev = new; |
42 | next->prev = new; |
43 | new->next = next; |
43 | new->next = next; |
44 | new->prev = prev; |
44 | new->prev = prev; |
45 | prev->next = new; |
45 | WRITE_ONCE(prev->next, new); |
46 | } |
46 | } |
47 | #else |
47 | #else |
48 | extern void __list_add(struct list_head *new, |
48 | extern void __list_add(struct list_head *new, |
49 | struct list_head *prev, |
49 | struct list_head *prev, |
50 | struct list_head *next); |
50 | struct list_head *next); |
51 | #endif |
51 | #endif |
52 | 52 | ||
53 | /** |
53 | /** |
54 | * list_add - add a new entry |
54 | * list_add - add a new entry |
55 | * @new: new entry to be added |
55 | * @new: new entry to be added |
56 | * @head: list head to add it after |
56 | * @head: list head to add it after |
57 | * |
57 | * |
58 | * Insert a new entry after the specified head. |
58 | * Insert a new entry after the specified head. |
59 | * This is good for implementing stacks. |
59 | * This is good for implementing stacks. |
60 | */ |
60 | */ |
61 | static inline void list_add(struct list_head *new, struct list_head *head) |
61 | static inline void list_add(struct list_head *new, struct list_head *head) |
62 | { |
62 | { |
63 | __list_add(new, head, head->next); |
63 | __list_add(new, head, head->next); |
64 | } |
64 | } |
65 | 65 | ||
66 | 66 | ||
67 | /** |
67 | /** |
68 | * list_add_tail - add a new entry |
68 | * list_add_tail - add a new entry |
69 | * @new: new entry to be added |
69 | * @new: new entry to be added |
70 | * @head: list head to add it before |
70 | * @head: list head to add it before |
71 | * |
71 | * |
72 | * Insert a new entry before the specified head. |
72 | * Insert a new entry before the specified head. |
73 | * This is useful for implementing queues. |
73 | * This is useful for implementing queues. |
74 | */ |
74 | */ |
75 | static inline void list_add_tail(struct list_head *new, struct list_head *head) |
75 | static inline void list_add_tail(struct list_head *new, struct list_head *head) |
76 | { |
76 | { |
77 | __list_add(new, head->prev, head); |
77 | __list_add(new, head->prev, head); |
78 | } |
78 | } |
79 | 79 | ||
80 | /* |
80 | /* |
81 | * Delete a list entry by making the prev/next entries |
81 | * Delete a list entry by making the prev/next entries |
82 | * point to each other. |
82 | * point to each other. |
83 | * |
83 | * |
84 | * This is only for internal list manipulation where we know |
84 | * This is only for internal list manipulation where we know |
85 | * the prev/next entries already! |
85 | * the prev/next entries already! |
86 | */ |
86 | */ |
87 | static inline void __list_del(struct list_head * prev, struct list_head * next) |
87 | static inline void __list_del(struct list_head * prev, struct list_head * next) |
88 | { |
88 | { |
89 | next->prev = prev; |
89 | next->prev = prev; |
90 | WRITE_ONCE(prev->next, next); |
90 | WRITE_ONCE(prev->next, next); |
91 | } |
91 | } |
92 | 92 | ||
93 | /** |
93 | /** |
94 | * list_del - deletes entry from list. |
94 | * list_del - deletes entry from list. |
95 | * @entry: the element to delete from the list. |
95 | * @entry: the element to delete from the list. |
96 | * Note: list_empty() on entry does not return true after this, the entry is |
96 | * Note: list_empty() on entry does not return true after this, the entry is |
97 | * in an undefined state. |
97 | * in an undefined state. |
98 | */ |
98 | */ |
99 | #ifndef CONFIG_DEBUG_LIST |
99 | #ifndef CONFIG_DEBUG_LIST |
100 | static inline void __list_del_entry(struct list_head *entry) |
100 | static inline void __list_del_entry(struct list_head *entry) |
101 | { |
101 | { |
102 | __list_del(entry->prev, entry->next); |
102 | __list_del(entry->prev, entry->next); |
103 | } |
103 | } |
104 | 104 | ||
105 | static inline void list_del(struct list_head *entry) |
105 | static inline void list_del(struct list_head *entry) |
106 | { |
106 | { |
107 | __list_del(entry->prev, entry->next); |
107 | __list_del(entry->prev, entry->next); |
108 | entry->next = LIST_POISON1; |
108 | entry->next = LIST_POISON1; |
109 | entry->prev = LIST_POISON2; |
109 | entry->prev = LIST_POISON2; |
110 | } |
110 | } |
111 | #else |
111 | #else |
112 | extern void __list_del_entry(struct list_head *entry); |
112 | extern void __list_del_entry(struct list_head *entry); |
113 | extern void list_del(struct list_head *entry); |
113 | extern void list_del(struct list_head *entry); |
114 | #endif |
114 | #endif |
115 | 115 | ||
116 | /** |
116 | /** |
117 | * list_replace - replace old entry by new one |
117 | * list_replace - replace old entry by new one |
118 | * @old : the element to be replaced |
118 | * @old : the element to be replaced |
119 | * @new : the new element to insert |
119 | * @new : the new element to insert |
120 | * |
120 | * |
121 | * If @old was empty, it will be overwritten. |
121 | * If @old was empty, it will be overwritten. |
122 | */ |
122 | */ |
123 | static inline void list_replace(struct list_head *old, |
123 | static inline void list_replace(struct list_head *old, |
124 | struct list_head *new) |
124 | struct list_head *new) |
125 | { |
125 | { |
126 | new->next = old->next; |
126 | new->next = old->next; |
127 | new->next->prev = new; |
127 | new->next->prev = new; |
128 | new->prev = old->prev; |
128 | new->prev = old->prev; |
129 | new->prev->next = new; |
129 | new->prev->next = new; |
130 | } |
130 | } |
131 | 131 | ||
132 | static inline void list_replace_init(struct list_head *old, |
132 | static inline void list_replace_init(struct list_head *old, |
133 | struct list_head *new) |
133 | struct list_head *new) |
134 | { |
134 | { |
135 | list_replace(old, new); |
135 | list_replace(old, new); |
136 | INIT_LIST_HEAD(old); |
136 | INIT_LIST_HEAD(old); |
137 | } |
137 | } |
138 | 138 | ||
139 | /** |
139 | /** |
140 | * list_del_init - deletes entry from list and reinitialize it. |
140 | * list_del_init - deletes entry from list and reinitialize it. |
141 | * @entry: the element to delete from the list. |
141 | * @entry: the element to delete from the list. |
142 | */ |
142 | */ |
143 | static inline void list_del_init(struct list_head *entry) |
143 | static inline void list_del_init(struct list_head *entry) |
144 | { |
144 | { |
145 | __list_del_entry(entry); |
145 | __list_del_entry(entry); |
146 | INIT_LIST_HEAD(entry); |
146 | INIT_LIST_HEAD(entry); |
147 | } |
147 | } |
148 | 148 | ||
149 | /** |
149 | /** |
150 | * list_move - delete from one list and add as another's head |
150 | * list_move - delete from one list and add as another's head |
151 | * @list: the entry to move |
151 | * @list: the entry to move |
152 | * @head: the head that will precede our entry |
152 | * @head: the head that will precede our entry |
153 | */ |
153 | */ |
154 | static inline void list_move(struct list_head *list, struct list_head *head) |
154 | static inline void list_move(struct list_head *list, struct list_head *head) |
155 | { |
155 | { |
156 | __list_del_entry(list); |
156 | __list_del_entry(list); |
157 | list_add(list, head); |
157 | list_add(list, head); |
158 | } |
158 | } |
159 | 159 | ||
160 | /** |
160 | /** |
161 | * list_move_tail - delete from one list and add as another's tail |
161 | * list_move_tail - delete from one list and add as another's tail |
162 | * @list: the entry to move |
162 | * @list: the entry to move |
163 | * @head: the head that will follow our entry |
163 | * @head: the head that will follow our entry |
164 | */ |
164 | */ |
165 | static inline void list_move_tail(struct list_head *list, |
165 | static inline void list_move_tail(struct list_head *list, |
166 | struct list_head *head) |
166 | struct list_head *head) |
167 | { |
167 | { |
168 | __list_del_entry(list); |
168 | __list_del_entry(list); |
169 | list_add_tail(list, head); |
169 | list_add_tail(list, head); |
170 | } |
170 | } |
171 | 171 | ||
172 | /** |
172 | /** |
173 | * list_is_last - tests whether @list is the last entry in list @head |
173 | * list_is_last - tests whether @list is the last entry in list @head |
174 | * @list: the entry to test |
174 | * @list: the entry to test |
175 | * @head: the head of the list |
175 | * @head: the head of the list |
176 | */ |
176 | */ |
177 | static inline int list_is_last(const struct list_head *list, |
177 | static inline int list_is_last(const struct list_head *list, |
178 | const struct list_head *head) |
178 | const struct list_head *head) |
179 | { |
179 | { |
180 | return list->next == head; |
180 | return list->next == head; |
181 | } |
181 | } |
182 | 182 | ||
183 | /** |
183 | /** |
184 | * list_empty - tests whether a list is empty |
184 | * list_empty - tests whether a list is empty |
185 | * @head: the list to test. |
185 | * @head: the list to test. |
186 | */ |
186 | */ |
187 | static inline int list_empty(const struct list_head *head) |
187 | static inline int list_empty(const struct list_head *head) |
188 | { |
188 | { |
189 | return head->next == head; |
189 | return READ_ONCE(head->next) == head; |
190 | } |
190 | } |
191 | 191 | ||
192 | /** |
192 | /** |
193 | * list_empty_careful - tests whether a list is empty and not being modified |
193 | * list_empty_careful - tests whether a list is empty and not being modified |
194 | * @head: the list to test |
194 | * @head: the list to test |
195 | * |
195 | * |
196 | * Description: |
196 | * Description: |
197 | * tests whether a list is empty _and_ checks that no other CPU might be |
197 | * tests whether a list is empty _and_ checks that no other CPU might be |
198 | * in the process of modifying either member (next or prev) |
198 | * in the process of modifying either member (next or prev) |
199 | * |
199 | * |
200 | * NOTE: using list_empty_careful() without synchronization |
200 | * NOTE: using list_empty_careful() without synchronization |
201 | * can only be safe if the only activity that can happen |
201 | * can only be safe if the only activity that can happen |
202 | * to the list entry is list_del_init(). Eg. it cannot be used |
202 | * to the list entry is list_del_init(). Eg. it cannot be used |
203 | * if another CPU could re-list_add() it. |
203 | * if another CPU could re-list_add() it. |
204 | */ |
204 | */ |
205 | static inline int list_empty_careful(const struct list_head *head) |
205 | static inline int list_empty_careful(const struct list_head *head) |
206 | { |
206 | { |
207 | struct list_head *next = head->next; |
207 | struct list_head *next = head->next; |
208 | return (next == head) && (next == head->prev); |
208 | return (next == head) && (next == head->prev); |
209 | } |
209 | } |
210 | 210 | ||
211 | /** |
211 | /** |
212 | * list_rotate_left - rotate the list to the left |
212 | * list_rotate_left - rotate the list to the left |
213 | * @head: the head of the list |
213 | * @head: the head of the list |
214 | */ |
214 | */ |
215 | static inline void list_rotate_left(struct list_head *head) |
215 | static inline void list_rotate_left(struct list_head *head) |
216 | { |
216 | { |
217 | struct list_head *first; |
217 | struct list_head *first; |
218 | 218 | ||
219 | if (!list_empty(head)) { |
219 | if (!list_empty(head)) { |
220 | first = head->next; |
220 | first = head->next; |
221 | list_move_tail(first, head); |
221 | list_move_tail(first, head); |
222 | } |
222 | } |
223 | } |
223 | } |
224 | 224 | ||
225 | /** |
225 | /** |
226 | * list_is_singular - tests whether a list has just one entry. |
226 | * list_is_singular - tests whether a list has just one entry. |
227 | * @head: the list to test. |
227 | * @head: the list to test. |
228 | */ |
228 | */ |
229 | static inline int list_is_singular(const struct list_head *head) |
229 | static inline int list_is_singular(const struct list_head *head) |
230 | { |
230 | { |
231 | return !list_empty(head) && (head->next == head->prev); |
231 | return !list_empty(head) && (head->next == head->prev); |
232 | } |
232 | } |
233 | 233 | ||
234 | static inline void __list_cut_position(struct list_head *list, |
234 | static inline void __list_cut_position(struct list_head *list, |
235 | struct list_head *head, struct list_head *entry) |
235 | struct list_head *head, struct list_head *entry) |
236 | { |
236 | { |
237 | struct list_head *new_first = entry->next; |
237 | struct list_head *new_first = entry->next; |
238 | list->next = head->next; |
238 | list->next = head->next; |
239 | list->next->prev = list; |
239 | list->next->prev = list; |
240 | list->prev = entry; |
240 | list->prev = entry; |
241 | entry->next = list; |
241 | entry->next = list; |
242 | head->next = new_first; |
242 | head->next = new_first; |
243 | new_first->prev = head; |
243 | new_first->prev = head; |
244 | } |
244 | } |
245 | 245 | ||
246 | /** |
246 | /** |
247 | * list_cut_position - cut a list into two |
247 | * list_cut_position - cut a list into two |
248 | * @list: a new list to add all removed entries |
248 | * @list: a new list to add all removed entries |
249 | * @head: a list with entries |
249 | * @head: a list with entries |
250 | * @entry: an entry within head, could be the head itself |
250 | * @entry: an entry within head, could be the head itself |
251 | * and if so we won't cut the list |
251 | * and if so we won't cut the list |
252 | * |
252 | * |
253 | * This helper moves the initial part of @head, up to and |
253 | * This helper moves the initial part of @head, up to and |
254 | * including @entry, from @head to @list. You should |
254 | * including @entry, from @head to @list. You should |
255 | * pass on @entry an element you know is on @head. @list |
255 | * pass on @entry an element you know is on @head. @list |
256 | * should be an empty list or a list you do not care about |
256 | * should be an empty list or a list you do not care about |
257 | * losing its data. |
257 | * losing its data. |
258 | * |
258 | * |
259 | */ |
259 | */ |
260 | static inline void list_cut_position(struct list_head *list, |
260 | static inline void list_cut_position(struct list_head *list, |
261 | struct list_head *head, struct list_head *entry) |
261 | struct list_head *head, struct list_head *entry) |
262 | { |
262 | { |
263 | if (list_empty(head)) |
263 | if (list_empty(head)) |
264 | return; |
264 | return; |
265 | if (list_is_singular(head) && |
265 | if (list_is_singular(head) && |
266 | (head->next != entry && head != entry)) |
266 | (head->next != entry && head != entry)) |
267 | return; |
267 | return; |
268 | if (entry == head) |
268 | if (entry == head) |
269 | INIT_LIST_HEAD(list); |
269 | INIT_LIST_HEAD(list); |
270 | else |
270 | else |
271 | __list_cut_position(list, head, entry); |
271 | __list_cut_position(list, head, entry); |
272 | } |
272 | } |
273 | 273 | ||
274 | static inline void __list_splice(const struct list_head *list, |
274 | static inline void __list_splice(const struct list_head *list, |
275 | struct list_head *prev, |
275 | struct list_head *prev, |
276 | struct list_head *next) |
276 | struct list_head *next) |
277 | { |
277 | { |
278 | struct list_head *first = list->next; |
278 | struct list_head *first = list->next; |
279 | struct list_head *last = list->prev; |
279 | struct list_head *last = list->prev; |
280 | 280 | ||
281 | first->prev = prev; |
281 | first->prev = prev; |
282 | prev->next = first; |
282 | prev->next = first; |
283 | 283 | ||
284 | last->next = next; |
284 | last->next = next; |
285 | next->prev = last; |
285 | next->prev = last; |
286 | } |
286 | } |
287 | 287 | ||
288 | /** |
288 | /** |
289 | * list_splice - join two lists, this is designed for stacks |
289 | * list_splice - join two lists, this is designed for stacks |
290 | * @list: the new list to add. |
290 | * @list: the new list to add. |
291 | * @head: the place to add it in the first list. |
291 | * @head: the place to add it in the first list. |
292 | */ |
292 | */ |
293 | static inline void list_splice(const struct list_head *list, |
293 | static inline void list_splice(const struct list_head *list, |
294 | struct list_head *head) |
294 | struct list_head *head) |
295 | { |
295 | { |
296 | if (!list_empty(list)) |
296 | if (!list_empty(list)) |
297 | __list_splice(list, head, head->next); |
297 | __list_splice(list, head, head->next); |
298 | } |
298 | } |
299 | 299 | ||
300 | /** |
300 | /** |
301 | * list_splice_tail - join two lists, each list being a queue |
301 | * list_splice_tail - join two lists, each list being a queue |
302 | * @list: the new list to add. |
302 | * @list: the new list to add. |
303 | * @head: the place to add it in the first list. |
303 | * @head: the place to add it in the first list. |
304 | */ |
304 | */ |
305 | static inline void list_splice_tail(struct list_head *list, |
305 | static inline void list_splice_tail(struct list_head *list, |
306 | struct list_head *head) |
306 | struct list_head *head) |
307 | { |
307 | { |
308 | if (!list_empty(list)) |
308 | if (!list_empty(list)) |
309 | __list_splice(list, head->prev, head); |
309 | __list_splice(list, head->prev, head); |
310 | } |
310 | } |
311 | 311 | ||
312 | /** |
312 | /** |
313 | * list_splice_init - join two lists and reinitialise the emptied list. |
313 | * list_splice_init - join two lists and reinitialise the emptied list. |
314 | * @list: the new list to add. |
314 | * @list: the new list to add. |
315 | * @head: the place to add it in the first list. |
315 | * @head: the place to add it in the first list. |
316 | * |
316 | * |
317 | * The list at @list is reinitialised |
317 | * The list at @list is reinitialised |
318 | */ |
318 | */ |
319 | static inline void list_splice_init(struct list_head *list, |
319 | static inline void list_splice_init(struct list_head *list, |
320 | struct list_head *head) |
320 | struct list_head *head) |
321 | { |
321 | { |
322 | if (!list_empty(list)) { |
322 | if (!list_empty(list)) { |
323 | __list_splice(list, head, head->next); |
323 | __list_splice(list, head, head->next); |
324 | INIT_LIST_HEAD(list); |
324 | INIT_LIST_HEAD(list); |
325 | } |
325 | } |
326 | } |
326 | } |
327 | 327 | ||
328 | /** |
328 | /** |
329 | * list_splice_tail_init - join two lists and reinitialise the emptied list |
329 | * list_splice_tail_init - join two lists and reinitialise the emptied list |
330 | * @list: the new list to add. |
330 | * @list: the new list to add. |
331 | * @head: the place to add it in the first list. |
331 | * @head: the place to add it in the first list. |
332 | * |
332 | * |
333 | * Each of the lists is a queue. |
333 | * Each of the lists is a queue. |
334 | * The list at @list is reinitialised |
334 | * The list at @list is reinitialised |
335 | */ |
335 | */ |
336 | static inline void list_splice_tail_init(struct list_head *list, |
336 | static inline void list_splice_tail_init(struct list_head *list, |
337 | struct list_head *head) |
337 | struct list_head *head) |
338 | { |
338 | { |
339 | if (!list_empty(list)) { |
339 | if (!list_empty(list)) { |
340 | __list_splice(list, head->prev, head); |
340 | __list_splice(list, head->prev, head); |
341 | INIT_LIST_HEAD(list); |
341 | INIT_LIST_HEAD(list); |
342 | } |
342 | } |
343 | } |
343 | } |
344 | 344 | ||
345 | /** |
345 | /** |
346 | * list_entry - get the struct for this entry |
346 | * list_entry - get the struct for this entry |
347 | * @ptr: the &struct list_head pointer. |
347 | * @ptr: the &struct list_head pointer. |
348 | * @type: the type of the struct this is embedded in. |
348 | * @type: the type of the struct this is embedded in. |
349 | * @member: the name of the list_head within the struct. |
349 | * @member: the name of the list_head within the struct. |
350 | */ |
350 | */ |
351 | #define list_entry(ptr, type, member) \ |
351 | #define list_entry(ptr, type, member) \ |
352 | container_of(ptr, type, member) |
352 | container_of(ptr, type, member) |
353 | 353 | ||
354 | /** |
354 | /** |
355 | * list_first_entry - get the first element from a list |
355 | * list_first_entry - get the first element from a list |
356 | * @ptr: the list head to take the element from. |
356 | * @ptr: the list head to take the element from. |
357 | * @type: the type of the struct this is embedded in. |
357 | * @type: the type of the struct this is embedded in. |
358 | * @member: the name of the list_head within the struct. |
358 | * @member: the name of the list_head within the struct. |
359 | * |
359 | * |
360 | * Note, that list is expected to be not empty. |
360 | * Note, that list is expected to be not empty. |
361 | */ |
361 | */ |
362 | #define list_first_entry(ptr, type, member) \ |
362 | #define list_first_entry(ptr, type, member) \ |
363 | list_entry((ptr)->next, type, member) |
363 | list_entry((ptr)->next, type, member) |
364 | 364 | ||
365 | /** |
365 | /** |
366 | * list_last_entry - get the last element from a list |
366 | * list_last_entry - get the last element from a list |
367 | * @ptr: the list head to take the element from. |
367 | * @ptr: the list head to take the element from. |
368 | * @type: the type of the struct this is embedded in. |
368 | * @type: the type of the struct this is embedded in. |
369 | * @member: the name of the list_head within the struct. |
369 | * @member: the name of the list_head within the struct. |
370 | * |
370 | * |
371 | * Note, that list is expected to be not empty. |
371 | * Note, that list is expected to be not empty. |
372 | */ |
372 | */ |
373 | #define list_last_entry(ptr, type, member) \ |
373 | #define list_last_entry(ptr, type, member) \ |
374 | list_entry((ptr)->prev, type, member) |
374 | list_entry((ptr)->prev, type, member) |
375 | 375 | ||
376 | /** |
376 | /** |
377 | * list_first_entry_or_null - get the first element from a list |
377 | * list_first_entry_or_null - get the first element from a list |
378 | * @ptr: the list head to take the element from. |
378 | * @ptr: the list head to take the element from. |
379 | * @type: the type of the struct this is embedded in. |
379 | * @type: the type of the struct this is embedded in. |
380 | * @member: the name of the list_head within the struct. |
380 | * @member: the name of the list_head within the struct. |
381 | * |
381 | * |
382 | * Note that if the list is empty, it returns NULL. |
382 | * Note that if the list is empty, it returns NULL. |
383 | */ |
383 | */ |
384 | #define list_first_entry_or_null(ptr, type, member) \ |
384 | #define list_first_entry_or_null(ptr, type, member) \ |
385 | (!list_empty(ptr) ? list_first_entry(ptr, type, member) : NULL) |
385 | (!list_empty(ptr) ? list_first_entry(ptr, type, member) : NULL) |
386 | 386 | ||
387 | /** |
387 | /** |
388 | * list_next_entry - get the next element in list |
388 | * list_next_entry - get the next element in list |
389 | * @pos: the type * to cursor |
389 | * @pos: the type * to cursor |
390 | * @member: the name of the list_head within the struct. |
390 | * @member: the name of the list_head within the struct. |
391 | */ |
391 | */ |
392 | #define list_next_entry(pos, member) \ |
392 | #define list_next_entry(pos, member) \ |
393 | list_entry((pos)->member.next, typeof(*(pos)), member) |
393 | list_entry((pos)->member.next, typeof(*(pos)), member) |
394 | 394 | ||
395 | /** |
395 | /** |
396 | * list_prev_entry - get the prev element in list |
396 | * list_prev_entry - get the prev element in list |
397 | * @pos: the type * to cursor |
397 | * @pos: the type * to cursor |
398 | * @member: the name of the list_head within the struct. |
398 | * @member: the name of the list_head within the struct. |
399 | */ |
399 | */ |
400 | #define list_prev_entry(pos, member) \ |
400 | #define list_prev_entry(pos, member) \ |
401 | list_entry((pos)->member.prev, typeof(*(pos)), member) |
401 | list_entry((pos)->member.prev, typeof(*(pos)), member) |
402 | 402 | ||
403 | /** |
403 | /** |
404 | * list_for_each - iterate over a list |
404 | * list_for_each - iterate over a list |
405 | * @pos: the &struct list_head to use as a loop cursor. |
405 | * @pos: the &struct list_head to use as a loop cursor. |
406 | * @head: the head for your list. |
406 | * @head: the head for your list. |
407 | */ |
407 | */ |
408 | #define list_for_each(pos, head) \ |
408 | #define list_for_each(pos, head) \ |
409 | for (pos = (head)->next; pos != (head); pos = pos->next) |
409 | for (pos = (head)->next; pos != (head); pos = pos->next) |
410 | 410 | ||
411 | /** |
411 | /** |
412 | * list_for_each_prev - iterate over a list backwards |
412 | * list_for_each_prev - iterate over a list backwards |
413 | * @pos: the &struct list_head to use as a loop cursor. |
413 | * @pos: the &struct list_head to use as a loop cursor. |
414 | * @head: the head for your list. |
414 | * @head: the head for your list. |
415 | */ |
415 | */ |
416 | #define list_for_each_prev(pos, head) \ |
416 | #define list_for_each_prev(pos, head) \ |
417 | for (pos = (head)->prev; pos != (head); pos = pos->prev) |
417 | for (pos = (head)->prev; pos != (head); pos = pos->prev) |
418 | 418 | ||
419 | /** |
419 | /** |
420 | * list_for_each_safe - iterate over a list safe against removal of list entry |
420 | * list_for_each_safe - iterate over a list safe against removal of list entry |
421 | * @pos: the &struct list_head to use as a loop cursor. |
421 | * @pos: the &struct list_head to use as a loop cursor. |
422 | * @n: another &struct list_head to use as temporary storage |
422 | * @n: another &struct list_head to use as temporary storage |
423 | * @head: the head for your list. |
423 | * @head: the head for your list. |
424 | */ |
424 | */ |
425 | #define list_for_each_safe(pos, n, head) \ |
425 | #define list_for_each_safe(pos, n, head) \ |
426 | for (pos = (head)->next, n = pos->next; pos != (head); \ |
426 | for (pos = (head)->next, n = pos->next; pos != (head); \ |
427 | pos = n, n = pos->next) |
427 | pos = n, n = pos->next) |
428 | 428 | ||
429 | /** |
429 | /** |
430 | * list_for_each_prev_safe - iterate over a list backwards safe against removal of list entry |
430 | * list_for_each_prev_safe - iterate over a list backwards safe against removal of list entry |
431 | * @pos: the &struct list_head to use as a loop cursor. |
431 | * @pos: the &struct list_head to use as a loop cursor. |
432 | * @n: another &struct list_head to use as temporary storage |
432 | * @n: another &struct list_head to use as temporary storage |
433 | * @head: the head for your list. |
433 | * @head: the head for your list. |
434 | */ |
434 | */ |
435 | #define list_for_each_prev_safe(pos, n, head) \ |
435 | #define list_for_each_prev_safe(pos, n, head) \ |
436 | for (pos = (head)->prev, n = pos->prev; \ |
436 | for (pos = (head)->prev, n = pos->prev; \ |
437 | pos != (head); \ |
437 | pos != (head); \ |
438 | pos = n, n = pos->prev) |
438 | pos = n, n = pos->prev) |
439 | 439 | ||
440 | /** |
440 | /** |
441 | * list_for_each_entry - iterate over list of given type |
441 | * list_for_each_entry - iterate over list of given type |
442 | * @pos: the type * to use as a loop cursor. |
442 | * @pos: the type * to use as a loop cursor. |
443 | * @head: the head for your list. |
443 | * @head: the head for your list. |
444 | * @member: the name of the list_head within the struct. |
444 | * @member: the name of the list_head within the struct. |
445 | */ |
445 | */ |
446 | #define list_for_each_entry(pos, head, member) \ |
446 | #define list_for_each_entry(pos, head, member) \ |
447 | for (pos = list_first_entry(head, typeof(*pos), member); \ |
447 | for (pos = list_first_entry(head, typeof(*pos), member); \ |
448 | &pos->member != (head); \ |
448 | &pos->member != (head); \ |
449 | pos = list_next_entry(pos, member)) |
449 | pos = list_next_entry(pos, member)) |
450 | 450 | ||
451 | /** |
451 | /** |
452 | * list_for_each_entry_reverse - iterate backwards over list of given type. |
452 | * list_for_each_entry_reverse - iterate backwards over list of given type. |
453 | * @pos: the type * to use as a loop cursor. |
453 | * @pos: the type * to use as a loop cursor. |
454 | * @head: the head for your list. |
454 | * @head: the head for your list. |
455 | * @member: the name of the list_head within the struct. |
455 | * @member: the name of the list_head within the struct. |
456 | */ |
456 | */ |
457 | #define list_for_each_entry_reverse(pos, head, member) \ |
457 | #define list_for_each_entry_reverse(pos, head, member) \ |
458 | for (pos = list_last_entry(head, typeof(*pos), member); \ |
458 | for (pos = list_last_entry(head, typeof(*pos), member); \ |
459 | &pos->member != (head); \ |
459 | &pos->member != (head); \ |
460 | pos = list_prev_entry(pos, member)) |
460 | pos = list_prev_entry(pos, member)) |
461 | 461 | ||
462 | /** |
462 | /** |
463 | * list_prepare_entry - prepare a pos entry for use in list_for_each_entry_continue() |
463 | * list_prepare_entry - prepare a pos entry for use in list_for_each_entry_continue() |
464 | * @pos: the type * to use as a start point |
464 | * @pos: the type * to use as a start point |
465 | * @head: the head of the list |
465 | * @head: the head of the list |
466 | * @member: the name of the list_head within the struct. |
466 | * @member: the name of the list_head within the struct. |
467 | * |
467 | * |
468 | * Prepares a pos entry for use as a start point in list_for_each_entry_continue(). |
468 | * Prepares a pos entry for use as a start point in list_for_each_entry_continue(). |
469 | */ |
469 | */ |
470 | #define list_prepare_entry(pos, head, member) \ |
470 | #define list_prepare_entry(pos, head, member) \ |
471 | ((pos) ? : list_entry(head, typeof(*pos), member)) |
471 | ((pos) ? : list_entry(head, typeof(*pos), member)) |
472 | 472 | ||
473 | /** |
473 | /** |
474 | * list_for_each_entry_continue - continue iteration over list of given type |
474 | * list_for_each_entry_continue - continue iteration over list of given type |
475 | * @pos: the type * to use as a loop cursor. |
475 | * @pos: the type * to use as a loop cursor. |
476 | * @head: the head for your list. |
476 | * @head: the head for your list. |
477 | * @member: the name of the list_head within the struct. |
477 | * @member: the name of the list_head within the struct. |
478 | * |
478 | * |
479 | * Continue to iterate over list of given type, continuing after |
479 | * Continue to iterate over list of given type, continuing after |
480 | * the current position. |
480 | * the current position. |
481 | */ |
481 | */ |
482 | #define list_for_each_entry_continue(pos, head, member) \ |
482 | #define list_for_each_entry_continue(pos, head, member) \ |
483 | for (pos = list_next_entry(pos, member); \ |
483 | for (pos = list_next_entry(pos, member); \ |
484 | &pos->member != (head); \ |
484 | &pos->member != (head); \ |
485 | pos = list_next_entry(pos, member)) |
485 | pos = list_next_entry(pos, member)) |
486 | 486 | ||
487 | /** |
487 | /** |
488 | * list_for_each_entry_continue_reverse - iterate backwards from the given point |
488 | * list_for_each_entry_continue_reverse - iterate backwards from the given point |
489 | * @pos: the type * to use as a loop cursor. |
489 | * @pos: the type * to use as a loop cursor. |
490 | * @head: the head for your list. |
490 | * @head: the head for your list. |
491 | * @member: the name of the list_head within the struct. |
491 | * @member: the name of the list_head within the struct. |
492 | * |
492 | * |
493 | * Start to iterate over list of given type backwards, continuing after |
493 | * Start to iterate over list of given type backwards, continuing after |
494 | * the current position. |
494 | * the current position. |
495 | */ |
495 | */ |
496 | #define list_for_each_entry_continue_reverse(pos, head, member) \ |
496 | #define list_for_each_entry_continue_reverse(pos, head, member) \ |
497 | for (pos = list_prev_entry(pos, member); \ |
497 | for (pos = list_prev_entry(pos, member); \ |
498 | &pos->member != (head); \ |
498 | &pos->member != (head); \ |
499 | pos = list_prev_entry(pos, member)) |
499 | pos = list_prev_entry(pos, member)) |
500 | 500 | ||
501 | /** |
501 | /** |
502 | * list_for_each_entry_from - iterate over list of given type from the current point |
502 | * list_for_each_entry_from - iterate over list of given type from the current point |
503 | * @pos: the type * to use as a loop cursor. |
503 | * @pos: the type * to use as a loop cursor. |
504 | * @head: the head for your list. |
504 | * @head: the head for your list. |
505 | * @member: the name of the list_head within the struct. |
505 | * @member: the name of the list_head within the struct. |
506 | * |
506 | * |
507 | * Iterate over list of given type, continuing from current position. |
507 | * Iterate over list of given type, continuing from current position. |
508 | */ |
508 | */ |
509 | #define list_for_each_entry_from(pos, head, member) \ |
509 | #define list_for_each_entry_from(pos, head, member) \ |
510 | for (; &pos->member != (head); \ |
510 | for (; &pos->member != (head); \ |
511 | pos = list_next_entry(pos, member)) |
511 | pos = list_next_entry(pos, member)) |
512 | 512 | ||
513 | /** |
513 | /** |
514 | * list_for_each_entry_safe - iterate over list of given type safe against removal of list entry |
514 | * list_for_each_entry_safe - iterate over list of given type safe against removal of list entry |
515 | * @pos: the type * to use as a loop cursor. |
515 | * @pos: the type * to use as a loop cursor. |
516 | * @n: another type * to use as temporary storage |
516 | * @n: another type * to use as temporary storage |
517 | * @head: the head for your list. |
517 | * @head: the head for your list. |
518 | * @member: the name of the list_head within the struct. |
518 | * @member: the name of the list_head within the struct. |
519 | */ |
519 | */ |
520 | #define list_for_each_entry_safe(pos, n, head, member) \ |
520 | #define list_for_each_entry_safe(pos, n, head, member) \ |
521 | for (pos = list_first_entry(head, typeof(*pos), member), \ |
521 | for (pos = list_first_entry(head, typeof(*pos), member), \ |
522 | n = list_next_entry(pos, member); \ |
522 | n = list_next_entry(pos, member); \ |
523 | &pos->member != (head); \ |
523 | &pos->member != (head); \ |
524 | pos = n, n = list_next_entry(n, member)) |
524 | pos = n, n = list_next_entry(n, member)) |
525 | 525 | ||
526 | /** |
526 | /** |
527 | * list_for_each_entry_safe_continue - continue list iteration safe against removal |
527 | * list_for_each_entry_safe_continue - continue list iteration safe against removal |
528 | * @pos: the type * to use as a loop cursor. |
528 | * @pos: the type * to use as a loop cursor. |
529 | * @n: another type * to use as temporary storage |
529 | * @n: another type * to use as temporary storage |
530 | * @head: the head for your list. |
530 | * @head: the head for your list. |
531 | * @member: the name of the list_head within the struct. |
531 | * @member: the name of the list_head within the struct. |
532 | * |
532 | * |
533 | * Iterate over list of given type, continuing after current point, |
533 | * Iterate over list of given type, continuing after current point, |
534 | * safe against removal of list entry. |
534 | * safe against removal of list entry. |
535 | */ |
535 | */ |
536 | #define list_for_each_entry_safe_continue(pos, n, head, member) \ |
536 | #define list_for_each_entry_safe_continue(pos, n, head, member) \ |
537 | for (pos = list_next_entry(pos, member), \ |
537 | for (pos = list_next_entry(pos, member), \ |
538 | n = list_next_entry(pos, member); \ |
538 | n = list_next_entry(pos, member); \ |
539 | &pos->member != (head); \ |
539 | &pos->member != (head); \ |
540 | pos = n, n = list_next_entry(n, member)) |
540 | pos = n, n = list_next_entry(n, member)) |
541 | 541 | ||
542 | /** |
542 | /** |
543 | * list_for_each_entry_safe_from - iterate over list from current point safe against removal |
543 | * list_for_each_entry_safe_from - iterate over list from current point safe against removal |
544 | * @pos: the type * to use as a loop cursor. |
544 | * @pos: the type * to use as a loop cursor. |
545 | * @n: another type * to use as temporary storage |
545 | * @n: another type * to use as temporary storage |
546 | * @head: the head for your list. |
546 | * @head: the head for your list. |
547 | * @member: the name of the list_head within the struct. |
547 | * @member: the name of the list_head within the struct. |
548 | * |
548 | * |
549 | * Iterate over list of given type from current point, safe against |
549 | * Iterate over list of given type from current point, safe against |
550 | * removal of list entry. |
550 | * removal of list entry. |
551 | */ |
551 | */ |
552 | #define list_for_each_entry_safe_from(pos, n, head, member) \ |
552 | #define list_for_each_entry_safe_from(pos, n, head, member) \ |
553 | for (n = list_next_entry(pos, member); \ |
553 | for (n = list_next_entry(pos, member); \ |
554 | &pos->member != (head); \ |
554 | &pos->member != (head); \ |
555 | pos = n, n = list_next_entry(n, member)) |
555 | pos = n, n = list_next_entry(n, member)) |
556 | 556 | ||
557 | /** |
557 | /** |
558 | * list_for_each_entry_safe_reverse - iterate backwards over list safe against removal |
558 | * list_for_each_entry_safe_reverse - iterate backwards over list safe against removal |
559 | * @pos: the type * to use as a loop cursor. |
559 | * @pos: the type * to use as a loop cursor. |
560 | * @n: another type * to use as temporary storage |
560 | * @n: another type * to use as temporary storage |
561 | * @head: the head for your list. |
561 | * @head: the head for your list. |
562 | * @member: the name of the list_head within the struct. |
562 | * @member: the name of the list_head within the struct. |
563 | * |
563 | * |
564 | * Iterate backwards over list of given type, safe against removal |
564 | * Iterate backwards over list of given type, safe against removal |
565 | * of list entry. |
565 | * of list entry. |
566 | */ |
566 | */ |
567 | #define list_for_each_entry_safe_reverse(pos, n, head, member) \ |
567 | #define list_for_each_entry_safe_reverse(pos, n, head, member) \ |
568 | for (pos = list_last_entry(head, typeof(*pos), member), \ |
568 | for (pos = list_last_entry(head, typeof(*pos), member), \ |
569 | n = list_prev_entry(pos, member); \ |
569 | n = list_prev_entry(pos, member); \ |
570 | &pos->member != (head); \ |
570 | &pos->member != (head); \ |
571 | pos = n, n = list_prev_entry(n, member)) |
571 | pos = n, n = list_prev_entry(n, member)) |
572 | 572 | ||
573 | /** |
573 | /** |
574 | * list_safe_reset_next - reset a stale list_for_each_entry_safe loop |
574 | * list_safe_reset_next - reset a stale list_for_each_entry_safe loop |
575 | * @pos: the loop cursor used in the list_for_each_entry_safe loop |
575 | * @pos: the loop cursor used in the list_for_each_entry_safe loop |
576 | * @n: temporary storage used in list_for_each_entry_safe |
576 | * @n: temporary storage used in list_for_each_entry_safe |
577 | * @member: the name of the list_head within the struct. |
577 | * @member: the name of the list_head within the struct. |
578 | * |
578 | * |
579 | * list_safe_reset_next is not safe to use in general if the list may be |
579 | * list_safe_reset_next is not safe to use in general if the list may be |
580 | * modified concurrently (eg. the lock is dropped in the loop body). An |
580 | * modified concurrently (eg. the lock is dropped in the loop body). An |
581 | * exception to this is if the cursor element (pos) is pinned in the list, |
581 | * exception to this is if the cursor element (pos) is pinned in the list, |
582 | * and list_safe_reset_next is called after re-taking the lock and before |
582 | * and list_safe_reset_next is called after re-taking the lock and before |
583 | * completing the current iteration of the loop body. |
583 | * completing the current iteration of the loop body. |
584 | */ |
584 | */ |
585 | #define list_safe_reset_next(pos, n, member) \ |
585 | #define list_safe_reset_next(pos, n, member) \ |
586 | n = list_next_entry(pos, member) |
586 | n = list_next_entry(pos, member) |
587 | 587 | ||
588 | /* |
588 | /* |
589 | * Double linked lists with a single pointer list head. |
589 | * Double linked lists with a single pointer list head. |
590 | * Mostly useful for hash tables where the two pointer list head is |
590 | * Mostly useful for hash tables where the two pointer list head is |
591 | * too wasteful. |
591 | * too wasteful. |
592 | * You lose the ability to access the tail in O(1). |
592 | * You lose the ability to access the tail in O(1). |
593 | */ |
593 | */ |
594 | 594 | ||
595 | #define HLIST_HEAD_INIT { .first = NULL } |
595 | #define HLIST_HEAD_INIT { .first = NULL } |
596 | #define HLIST_HEAD(name) struct hlist_head name = { .first = NULL } |
596 | #define HLIST_HEAD(name) struct hlist_head name = { .first = NULL } |
597 | #define INIT_HLIST_HEAD(ptr) ((ptr)->first = NULL) |
597 | #define INIT_HLIST_HEAD(ptr) ((ptr)->first = NULL) |
598 | static inline void INIT_HLIST_NODE(struct hlist_node *h) |
598 | static inline void INIT_HLIST_NODE(struct hlist_node *h) |
599 | { |
599 | { |
600 | h->next = NULL; |
600 | h->next = NULL; |
601 | h->pprev = NULL; |
601 | h->pprev = NULL; |
602 | } |
602 | } |
603 | 603 | ||
604 | static inline int hlist_unhashed(const struct hlist_node *h) |
604 | static inline int hlist_unhashed(const struct hlist_node *h) |
605 | { |
605 | { |
606 | return !h->pprev; |
606 | return !h->pprev; |
607 | } |
607 | } |
608 | 608 | ||
609 | static inline int hlist_empty(const struct hlist_head *h) |
609 | static inline int hlist_empty(const struct hlist_head *h) |
610 | { |
610 | { |
611 | return !h->first; |
611 | return !READ_ONCE(h->first); |
612 | } |
612 | } |
613 | 613 | ||
614 | static inline void __hlist_del(struct hlist_node *n) |
614 | static inline void __hlist_del(struct hlist_node *n) |
615 | { |
615 | { |
616 | struct hlist_node *next = n->next; |
616 | struct hlist_node *next = n->next; |
617 | struct hlist_node **pprev = n->pprev; |
617 | struct hlist_node **pprev = n->pprev; |
618 | 618 | ||
619 | WRITE_ONCE(*pprev, next); |
619 | WRITE_ONCE(*pprev, next); |
620 | if (next) |
620 | if (next) |
621 | next->pprev = pprev; |
621 | next->pprev = pprev; |
622 | } |
622 | } |
623 | 623 | ||
624 | static inline void hlist_del(struct hlist_node *n) |
624 | static inline void hlist_del(struct hlist_node *n) |
625 | { |
625 | { |
626 | __hlist_del(n); |
626 | __hlist_del(n); |
627 | n->next = LIST_POISON1; |
627 | n->next = LIST_POISON1; |
628 | n->pprev = LIST_POISON2; |
628 | n->pprev = LIST_POISON2; |
629 | } |
629 | } |
630 | 630 | ||
631 | static inline void hlist_del_init(struct hlist_node *n) |
631 | static inline void hlist_del_init(struct hlist_node *n) |
632 | { |
632 | { |
633 | if (!hlist_unhashed(n)) { |
633 | if (!hlist_unhashed(n)) { |
634 | __hlist_del(n); |
634 | __hlist_del(n); |
635 | INIT_HLIST_NODE(n); |
635 | INIT_HLIST_NODE(n); |
636 | } |
636 | } |
637 | } |
637 | } |
638 | 638 | ||
639 | static inline void hlist_add_head(struct hlist_node *n, struct hlist_head *h) |
639 | static inline void hlist_add_head(struct hlist_node *n, struct hlist_head *h) |
640 | { |
640 | { |
641 | struct hlist_node *first = h->first; |
641 | struct hlist_node *first = h->first; |
642 | n->next = first; |
642 | n->next = first; |
643 | if (first) |
643 | if (first) |
644 | first->pprev = &n->next; |
644 | first->pprev = &n->next; |
645 | h->first = n; |
645 | WRITE_ONCE(h->first, n); |
646 | n->pprev = &h->first; |
646 | n->pprev = &h->first; |
647 | } |
647 | } |
648 | 648 | ||
649 | /* next must be != NULL */ |
649 | /* next must be != NULL */ |
650 | static inline void hlist_add_before(struct hlist_node *n, |
650 | static inline void hlist_add_before(struct hlist_node *n, |
651 | struct hlist_node *next) |
651 | struct hlist_node *next) |
652 | { |
652 | { |
653 | n->pprev = next->pprev; |
653 | n->pprev = next->pprev; |
654 | n->next = next; |
654 | n->next = next; |
655 | next->pprev = &n->next; |
655 | next->pprev = &n->next; |
656 | *(n->pprev) = n; |
656 | WRITE_ONCE(*(n->pprev), n); |
657 | } |
657 | } |
658 | 658 | ||
659 | static inline void hlist_add_behind(struct hlist_node *n, |
659 | static inline void hlist_add_behind(struct hlist_node *n, |
660 | struct hlist_node *prev) |
660 | struct hlist_node *prev) |
661 | { |
661 | { |
662 | n->next = prev->next; |
662 | n->next = prev->next; |
663 | prev->next = n; |
663 | WRITE_ONCE(prev->next, n); |
664 | n->pprev = &prev->next; |
664 | n->pprev = &prev->next; |
665 | 665 | ||
666 | if (n->next) |
666 | if (n->next) |
667 | n->next->pprev = &n->next; |
667 | n->next->pprev = &n->next; |
668 | } |
668 | } |
669 | 669 | ||
670 | /* after that we'll appear to be on some hlist and hlist_del will work */ |
670 | /* after that we'll appear to be on some hlist and hlist_del will work */ |
671 | static inline void hlist_add_fake(struct hlist_node *n) |
671 | static inline void hlist_add_fake(struct hlist_node *n) |
672 | { |
672 | { |
673 | n->pprev = &n->next; |
673 | n->pprev = &n->next; |
674 | } |
674 | } |
675 | 675 | ||
676 | static inline bool hlist_fake(struct hlist_node *h) |
676 | static inline bool hlist_fake(struct hlist_node *h) |
677 | { |
677 | { |
678 | return h->pprev == &h->next; |
678 | return h->pprev == &h->next; |
679 | } |
679 | } |
680 | 680 | ||
681 | /* |
681 | /* |
682 | * Move a list from one list head to another. Fixup the pprev |
682 | * Move a list from one list head to another. Fixup the pprev |
683 | * reference of the first entry if it exists. |
683 | * reference of the first entry if it exists. |
684 | */ |
684 | */ |
685 | static inline void hlist_move_list(struct hlist_head *old, |
685 | static inline void hlist_move_list(struct hlist_head *old, |
686 | struct hlist_head *new) |
686 | struct hlist_head *new) |
687 | { |
687 | { |
688 | new->first = old->first; |
688 | new->first = old->first; |
689 | if (new->first) |
689 | if (new->first) |
690 | new->first->pprev = &new->first; |
690 | new->first->pprev = &new->first; |
691 | old->first = NULL; |
691 | old->first = NULL; |
692 | } |
692 | } |
693 | 693 | ||
694 | #define hlist_entry(ptr, type, member) container_of(ptr,type,member) |
694 | #define hlist_entry(ptr, type, member) container_of(ptr,type,member) |
695 | 695 | ||
696 | #define hlist_for_each(pos, head) \ |
696 | #define hlist_for_each(pos, head) \ |
697 | for (pos = (head)->first; pos ; pos = pos->next) |
697 | for (pos = (head)->first; pos ; pos = pos->next) |
698 | 698 | ||
699 | #define hlist_for_each_safe(pos, n, head) \ |
699 | #define hlist_for_each_safe(pos, n, head) \ |
700 | for (pos = (head)->first; pos && ({ n = pos->next; 1; }); \ |
700 | for (pos = (head)->first; pos && ({ n = pos->next; 1; }); \ |
701 | pos = n) |
701 | pos = n) |
702 | 702 | ||
703 | #define hlist_entry_safe(ptr, type, member) \ |
703 | #define hlist_entry_safe(ptr, type, member) \ |
704 | ({ typeof(ptr) ____ptr = (ptr); \ |
704 | ({ typeof(ptr) ____ptr = (ptr); \ |
705 | ____ptr ? hlist_entry(____ptr, type, member) : NULL; \ |
705 | ____ptr ? hlist_entry(____ptr, type, member) : NULL; \ |
706 | }) |
706 | }) |
707 | 707 | ||
708 | /** |
708 | /** |
709 | * hlist_for_each_entry - iterate over list of given type |
709 | * hlist_for_each_entry - iterate over list of given type |
710 | * @pos: the type * to use as a loop cursor. |
710 | * @pos: the type * to use as a loop cursor. |
711 | * @head: the head for your list. |
711 | * @head: the head for your list. |
712 | * @member: the name of the hlist_node within the struct. |
712 | * @member: the name of the hlist_node within the struct. |
713 | */ |
713 | */ |
714 | #define hlist_for_each_entry(pos, head, member) \ |
714 | #define hlist_for_each_entry(pos, head, member) \ |
715 | for (pos = hlist_entry_safe((head)->first, typeof(*(pos)), member);\ |
715 | for (pos = hlist_entry_safe((head)->first, typeof(*(pos)), member);\ |
716 | pos; \ |
716 | pos; \ |
717 | pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member)) |
717 | pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member)) |
718 | 718 | ||
719 | /** |
719 | /** |
720 | * hlist_for_each_entry_continue - iterate over a hlist continuing after current point |
720 | * hlist_for_each_entry_continue - iterate over a hlist continuing after current point |
721 | * @pos: the type * to use as a loop cursor. |
721 | * @pos: the type * to use as a loop cursor. |
722 | * @member: the name of the hlist_node within the struct. |
722 | * @member: the name of the hlist_node within the struct. |
723 | */ |
723 | */ |
724 | #define hlist_for_each_entry_continue(pos, member) \ |
724 | #define hlist_for_each_entry_continue(pos, member) \ |
725 | for (pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member);\ |
725 | for (pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member);\ |
726 | pos; \ |
726 | pos; \ |
727 | pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member)) |
727 | pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member)) |
728 | 728 | ||
729 | /** |
729 | /** |
730 | * hlist_for_each_entry_from - iterate over a hlist continuing from current point |
730 | * hlist_for_each_entry_from - iterate over a hlist continuing from current point |
731 | * @pos: the type * to use as a loop cursor. |
731 | * @pos: the type * to use as a loop cursor. |
732 | * @member: the name of the hlist_node within the struct. |
732 | * @member: the name of the hlist_node within the struct. |
733 | */ |
733 | */ |
734 | #define hlist_for_each_entry_from(pos, member) \ |
734 | #define hlist_for_each_entry_from(pos, member) \ |
735 | for (; pos; \ |
735 | for (; pos; \ |
736 | pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member)) |
736 | pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member)) |
737 | 737 | ||
738 | /** |
738 | /** |
739 | * hlist_for_each_entry_safe - iterate over list of given type safe against removal of list entry |
739 | * hlist_for_each_entry_safe - iterate over list of given type safe against removal of list entry |
740 | * @pos: the type * to use as a loop cursor. |
740 | * @pos: the type * to use as a loop cursor. |
741 | * @n: another &struct hlist_node to use as temporary storage |
741 | * @n: another &struct hlist_node to use as temporary storage |
742 | * @head: the head for your list. |
742 | * @head: the head for your list. |
743 | * @member: the name of the hlist_node within the struct. |
743 | * @member: the name of the hlist_node within the struct. |
744 | */ |
744 | */ |
745 | #define hlist_for_each_entry_safe(pos, n, head, member) \ |
745 | #define hlist_for_each_entry_safe(pos, n, head, member) \ |
746 | for (pos = hlist_entry_safe((head)->first, typeof(*pos), member);\ |
746 | for (pos = hlist_entry_safe((head)->first, typeof(*pos), member);\ |
747 | pos && ({ n = pos->member.next; 1; }); \ |
747 | pos && ({ n = pos->member.next; 1; }); \ |
748 | pos = hlist_entry_safe(n, typeof(*pos), member)) |
748 | pos = hlist_entry_safe(n, typeof(*pos), member)) |
749 | 749 | ||
750 | #endif |
750 | #endif |