diff options
Diffstat (limited to 'include/linux/list.h')
| -rw-r--r-- | include/linux/list.h | 79 |
1 files changed, 53 insertions, 26 deletions
diff --git a/include/linux/list.h b/include/linux/list.h index f4d8a2f12a33..ef9594171062 100644 --- a/include/linux/list.h +++ b/include/linux/list.h @@ -362,6 +362,17 @@ static inline void list_splice_tail_init(struct list_head *list, list_entry((ptr)->next, type, member) /** + * list_last_entry - get the last element from a list + * @ptr: the list head to take the element from. + * @type: the type of the struct this is embedded in. + * @member: the name of the list_struct within the struct. + * + * Note, that list is expected to be not empty. + */ +#define list_last_entry(ptr, type, member) \ + list_entry((ptr)->prev, type, member) + +/** * list_first_entry_or_null - get the first element from a list * @ptr: the list head to take the element from. * @type: the type of the struct this is embedded in. @@ -373,6 +384,22 @@ static inline void list_splice_tail_init(struct list_head *list, (!list_empty(ptr) ? list_first_entry(ptr, type, member) : NULL) /** + * list_next_entry - get the next element in list + * @pos: the type * to cursor + * @member: the name of the list_struct within the struct. + */ +#define list_next_entry(pos, member) \ + list_entry((pos)->member.next, typeof(*(pos)), member) + +/** + * list_prev_entry - get the prev element in list + * @pos: the type * to cursor + * @member: the name of the list_struct within the struct. + */ +#define list_prev_entry(pos, member) \ + list_entry((pos)->member.prev, typeof(*(pos)), member) + +/** * list_for_each - iterate over a list * @pos: the &struct list_head to use as a loop cursor. * @head: the head for your list. @@ -416,9 +443,9 @@ static inline void list_splice_tail_init(struct list_head *list, * @member: the name of the list_struct within the struct. */ #define list_for_each_entry(pos, head, member) \ - for (pos = list_entry((head)->next, typeof(*pos), member); \ - &pos->member != (head); \ - pos = list_entry(pos->member.next, typeof(*pos), member)) + for (pos = list_first_entry(head, typeof(*pos), member); \ + &pos->member != (head); \ + pos = list_next_entry(pos, member)) /** * list_for_each_entry_reverse - iterate backwards over list of given type. @@ -427,9 +454,9 @@ static inline void list_splice_tail_init(struct list_head *list, * @member: the name of the list_struct within the struct. */ #define list_for_each_entry_reverse(pos, head, member) \ - for (pos = list_entry((head)->prev, typeof(*pos), member); \ - &pos->member != (head); \ - pos = list_entry(pos->member.prev, typeof(*pos), member)) + for (pos = list_last_entry(head, typeof(*pos), member); \ + &pos->member != (head); \ + pos = list_prev_entry(pos, member)) /** * list_prepare_entry - prepare a pos entry for use in list_for_each_entry_continue() @@ -452,9 +479,9 @@ static inline void list_splice_tail_init(struct list_head *list, * the current position. */ #define list_for_each_entry_continue(pos, head, member) \ - for (pos = list_entry(pos->member.next, typeof(*pos), member); \ - &pos->member != (head); \ - pos = list_entry(pos->member.next, typeof(*pos), member)) + for (pos = list_next_entry(pos, member); \ + &pos->member != (head); \ + pos = list_next_entry(pos, member)) /** * list_for_each_entry_continue_reverse - iterate backwards from the given point @@ -466,9 +493,9 @@ static inline void list_splice_tail_init(struct list_head *list, * the current position. */ #define list_for_each_entry_continue_reverse(pos, head, member) \ - for (pos = list_entry(pos->member.prev, typeof(*pos), member); \ - &pos->member != (head); \ - pos = list_entry(pos->member.prev, typeof(*pos), member)) + for (pos = list_prev_entry(pos, member); \ + &pos->member != (head); \ + pos = list_prev_entry(pos, member)) /** * list_for_each_entry_from - iterate over list of given type from the current point @@ -479,8 +506,8 @@ static inline void list_splice_tail_init(struct list_head *list, * Iterate over list of given type, continuing from current position. */ #define list_for_each_entry_from(pos, head, member) \ - for (; &pos->member != (head); \ - pos = list_entry(pos->member.next, typeof(*pos), member)) + for (; &pos->member != (head); \ + pos = list_next_entry(pos, member)) /** * list_for_each_entry_safe - iterate over list of given type safe against removal of list entry @@ -490,10 +517,10 @@ static inline void list_splice_tail_init(struct list_head *list, * @member: the name of the list_struct within the struct. */ #define list_for_each_entry_safe(pos, n, head, member) \ - for (pos = list_entry((head)->next, typeof(*pos), member), \ - n = list_entry(pos->member.next, typeof(*pos), member); \ + for (pos = list_first_entry(head, typeof(*pos), member), \ + n = list_next_entry(pos, member); \ &pos->member != (head); \ - pos = n, n = list_entry(n->member.next, typeof(*n), member)) + pos = n, n = list_next_entry(n, member)) /** * list_for_each_entry_safe_continue - continue list iteration safe against removal @@ -506,10 +533,10 @@ static inline void list_splice_tail_init(struct list_head *list, * safe against removal of list entry. */ #define list_for_each_entry_safe_continue(pos, n, head, member) \ - for (pos = list_entry(pos->member.next, typeof(*pos), member), \ - n = list_entry(pos->member.next, typeof(*pos), member); \ + for (pos = list_next_entry(pos, member), \ + n = list_next_entry(pos, member); \ &pos->member != (head); \ - pos = n, n = list_entry(n->member.next, typeof(*n), member)) + pos = n, n = list_next_entry(n, member)) /** * list_for_each_entry_safe_from - iterate over list from current point safe against removal @@ -522,9 +549,9 @@ static inline void list_splice_tail_init(struct list_head *list, * removal of list entry. */ #define list_for_each_entry_safe_from(pos, n, head, member) \ - for (n = list_entry(pos->member.next, typeof(*pos), member); \ + for (n = list_next_entry(pos, member); \ &pos->member != (head); \ - pos = n, n = list_entry(n->member.next, typeof(*n), member)) + pos = n, n = list_next_entry(n, member)) /** * list_for_each_entry_safe_reverse - iterate backwards over list safe against removal @@ -537,10 +564,10 @@ static inline void list_splice_tail_init(struct list_head *list, * of list entry. */ #define list_for_each_entry_safe_reverse(pos, n, head, member) \ - for (pos = list_entry((head)->prev, typeof(*pos), member), \ - n = list_entry(pos->member.prev, typeof(*pos), member); \ + for (pos = list_last_entry(head, typeof(*pos), member), \ + n = list_prev_entry(pos, member); \ &pos->member != (head); \ - pos = n, n = list_entry(n->member.prev, typeof(*n), member)) + pos = n, n = list_prev_entry(n, member)) /** * list_safe_reset_next - reset a stale list_for_each_entry_safe loop @@ -555,7 +582,7 @@ static inline void list_splice_tail_init(struct list_head *list, * completing the current iteration of the loop body. */ #define list_safe_reset_next(pos, n, member) \ - n = list_entry(pos->member.next, typeof(*pos), member) + n = list_next_entry(pos, member) /* * Double linked lists with a single pointer list head. |