--- zzzz-none-000/linux-3.10.107/include/linux/list.h 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/include/linux/list.h 2021-02-04 17:41:59.000000000 +0000 @@ -5,6 +5,7 @@ #include #include #include +#include /* * Simple doubly linked list implementation. @@ -86,7 +87,7 @@ static inline void __list_del(struct list_head * prev, struct list_head * next) { next->prev = prev; - prev->next = next; + WRITE_ONCE(prev->next, next); } /** @@ -345,7 +346,7 @@ * list_entry - get the struct for this entry * @ptr: the &struct list_head pointer. * @type: the type of the struct this is embedded in. - * @member: the name of the list_struct within the struct. + * @member: the name of the list_head within the struct. */ #define list_entry(ptr, type, member) \ container_of(ptr, type, member) @@ -354,7 +355,7 @@ * list_first_entry - 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. - * @member: the name of the list_struct within the struct. + * @member: the name of the list_head within the struct. * * Note, that list is expected to be not empty. */ @@ -362,10 +363,21 @@ 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_head 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. - * @member: the name of the list_struct within the struct. + * @member: the name of the list_head within the struct. * * Note that if the list is empty, it returns NULL. */ @@ -375,7 +387,7 @@ /** * list_next_entry - get the next element in list * @pos: the type * to cursor - * @member: the name of the list_struct within the struct. + * @member: the name of the list_head within the struct. */ #define list_next_entry(pos, member) \ list_entry((pos)->member.next, typeof(*(pos)), member) @@ -383,7 +395,7 @@ /** * list_prev_entry - get the prev element in list * @pos: the type * to cursor - * @member: the name of the list_struct within the struct. + * @member: the name of the list_head within the struct. */ #define list_prev_entry(pos, member) \ list_entry((pos)->member.prev, typeof(*(pos)), member) @@ -397,17 +409,6 @@ for (pos = (head)->next; pos != (head); pos = pos->next) /** - * __list_for_each - iterate over a list - * @pos: the &struct list_head to use as a loop cursor. - * @head: the head for your list. - * - * This variant doesn't differ from list_for_each() any more. - * We don't do prefetching in either case. - */ -#define __list_for_each(pos, head) \ - for (pos = (head)->next; pos != (head); pos = pos->next) - -/** * list_for_each_prev - iterate over a list backwards * @pos: the &struct list_head to use as a loop cursor. * @head: the head for your list. @@ -440,29 +441,29 @@ * list_for_each_entry - iterate over list of given type * @pos: the type * to use as a loop cursor. * @head: the head for your list. - * @member: the name of the list_struct within the struct. + * @member: the name of the list_head 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. * @pos: the type * to use as a loop cursor. * @head: the head for your list. - * @member: the name of the list_struct within the struct. + * @member: the name of the list_head 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() * @pos: the type * to use as a start point * @head: the head of the list - * @member: the name of the list_struct within the struct. + * @member: the name of the list_head within the struct. * * Prepares a pos entry for use as a start point in list_for_each_entry_continue(). */ @@ -473,107 +474,107 @@ * list_for_each_entry_continue - continue iteration over list of given type * @pos: the type * to use as a loop cursor. * @head: the head for your list. - * @member: the name of the list_struct within the struct. + * @member: the name of the list_head within the struct. * * Continue to iterate over list of given type, continuing after * 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 * @pos: the type * to use as a loop cursor. * @head: the head for your list. - * @member: the name of the list_struct within the struct. + * @member: the name of the list_head within the struct. * * Start to iterate over list of given type backwards, continuing after * 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 * @pos: the type * to use as a loop cursor. * @head: the head for your list. - * @member: the name of the list_struct within the struct. + * @member: the name of the list_head within the struct. * * 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 * @pos: the type * to use as a loop cursor. * @n: another type * to use as temporary storage * @head: the head for your list. - * @member: the name of the list_struct within the struct. + * @member: the name of the list_head 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 * @pos: the type * to use as a loop cursor. * @n: another type * to use as temporary storage * @head: the head for your list. - * @member: the name of the list_struct within the struct. + * @member: the name of the list_head within the struct. * * Iterate over list of given type, continuing after current point, * 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 * @pos: the type * to use as a loop cursor. * @n: another type * to use as temporary storage * @head: the head for your list. - * @member: the name of the list_struct within the struct. + * @member: the name of the list_head within the struct. * * Iterate over list of given type from current point, safe against * 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 * @pos: the type * to use as a loop cursor. * @n: another type * to use as temporary storage * @head: the head for your list. - * @member: the name of the list_struct within the struct. + * @member: the name of the list_head within the struct. * * Iterate backwards over list of given type, safe against removal * 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 * @pos: the loop cursor used in the list_for_each_entry_safe loop * @n: temporary storage used in list_for_each_entry_safe - * @member: the name of the list_struct within the struct. + * @member: the name of the list_head within the struct. * * list_safe_reset_next is not safe to use in general if the list may be * modified concurrently (eg. the lock is dropped in the loop body). An @@ -582,7 +583,7 @@ * 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. @@ -614,7 +615,8 @@ { struct hlist_node *next = n->next; struct hlist_node **pprev = n->pprev; - *pprev = next; + + WRITE_ONCE(*pprev, next); if (next) next->pprev = pprev; } @@ -654,15 +656,15 @@ *(n->pprev) = n; } -static inline void hlist_add_after(struct hlist_node *n, - struct hlist_node *next) +static inline void hlist_add_behind(struct hlist_node *n, + struct hlist_node *prev) { - next->next = n->next; - n->next = next; - next->pprev = &n->next; + n->next = prev->next; + prev->next = n; + n->pprev = &prev->next; - if(next->next) - next->next->pprev = &next->next; + if (n->next) + n->next->pprev = &n->next; } /* after that we'll appear to be on some hlist and hlist_del will work */ @@ -671,6 +673,11 @@ n->pprev = &n->next; } +static inline bool hlist_fake(struct hlist_node *h) +{ + return h->pprev == &h->next; +} + /* * Move a list from one list head to another. Fixup the pprev * reference of the first entry if it exists.