linux_list.h has macros and functions that mnl-api programs may want to use. Will have to add linux_list.h to the doxygen system, so cut out stuff we don't need to document. Update libnetfilter_queue.h to include linux_list.h. Signed-off-by: Duncan Roe <duncan_roe@xxxxxxxxxxxxxxx> --- .../libnetfilter_queue/libnetfilter_queue.h | 1 + include/libnetfilter_queue/linux_list.h | 586 +----------------- 2 files changed, 7 insertions(+), 580 deletions(-) diff --git a/include/libnetfilter_queue/libnetfilter_queue.h b/include/libnetfilter_queue/libnetfilter_queue.h index 9327f8c..9bd9c43 100644 --- a/include/libnetfilter_queue/libnetfilter_queue.h +++ b/include/libnetfilter_queue/libnetfilter_queue.h @@ -16,6 +16,7 @@ #include <sys/time.h> #include <libnfnetlink/libnfnetlink.h> +#include <libnetfilter_queue/linux_list.h> #include <libnetfilter_queue/linux_nfnetlink_queue.h> #ifdef __cplusplus diff --git a/include/libnetfilter_queue/linux_list.h b/include/libnetfilter_queue/linux_list.h index cf71837..eaa9c07 100644 --- a/include/libnetfilter_queue/linux_list.h +++ b/include/libnetfilter_queue/linux_list.h @@ -6,6 +6,12 @@ #undef offsetof #define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER) +/* + * This is a cut-down copy of libnfnetlink/include/linux_list.h which is itself + * an old snapshot of linux/include/linux/list.h. + * This file only contains what we use. + */ + /** * container_of - cast a member of a structure out to the containing structure * @@ -18,24 +24,8 @@ typeof( ((type *)0)->member ) *__mptr = (ptr); \ (type *)( (char *)__mptr - offsetof(type,member) );}) -/* - * Check at compile time that something is of a particular type. - * Always evaluates to 1 so you may use it easily in comparisons. - */ -#define typecheck(type,x) \ -({ type __dummy; \ - typeof(x) __dummy2; \ - (void)(&__dummy == &__dummy2); \ - 1; \ -}) - #define prefetch(x) ((void)0) -/* empty define to make this work in userspace -HW */ -#ifndef smp_wmb -#define smp_wmb() -#endif - /* * These are non-NULL pointers that will result in page faults * under normal circumstances, used to verify that nobody uses @@ -58,11 +48,6 @@ struct list_head { struct list_head *next, *prev; }; -#define LIST_HEAD_INIT(name) { &(name), &(name) } - -#define LIST_HEAD(name) \ - struct list_head name = LIST_HEAD_INIT(name) - #define INIT_LIST_HEAD(ptr) do { \ (ptr)->next = (ptr); (ptr)->prev = (ptr); \ } while (0) @@ -96,78 +81,6 @@ static inline void list_add(struct list_head *new, struct list_head *head) __list_add(new, head, head->next); } -/** - * list_add_tail - add a new entry - * @new: new entry to be added - * @head: list head to add it before - * - * Insert a new entry before the specified head. - * This is useful for implementing queues. - */ -static inline void list_add_tail(struct list_head *new, struct list_head *head) -{ - __list_add(new, head->prev, head); -} - -/* - * Insert a new entry between two known consecutive entries. - * - * This is only for internal list manipulation where we know - * the prev/next entries already! - */ -static inline void __list_add_rcu(struct list_head * new, - struct list_head * prev, struct list_head * next) -{ - new->next = next; - new->prev = prev; - smp_wmb(); - next->prev = new; - prev->next = new; -} - -/** - * list_add_rcu - add a new entry to rcu-protected list - * @new: new entry to be added - * @head: list head to add it after - * - * Insert a new entry after the specified head. - * This is good for implementing stacks. - * - * The caller must take whatever precautions are necessary - * (such as holding appropriate locks) to avoid racing - * with another list-mutation primitive, such as list_add_rcu() - * or list_del_rcu(), running on this same list. - * However, it is perfectly legal to run concurrently with - * the _rcu list-traversal primitives, such as - * list_for_each_entry_rcu(). - */ -static inline void list_add_rcu(struct list_head *new, struct list_head *head) -{ - __list_add_rcu(new, head, head->next); -} - -/** - * list_add_tail_rcu - add a new entry to rcu-protected list - * @new: new entry to be added - * @head: list head to add it before - * - * Insert a new entry before the specified head. - * This is useful for implementing queues. - * - * The caller must take whatever precautions are necessary - * (such as holding appropriate locks) to avoid racing - * with another list-mutation primitive, such as list_add_tail_rcu() - * or list_del_rcu(), running on this same list. - * However, it is perfectly legal to run concurrently with - * the _rcu list-traversal primitives, such as - * list_for_each_entry_rcu(). - */ -static inline void list_add_tail_rcu(struct list_head *new, - struct list_head *head) -{ - __list_add_rcu(new, head->prev, head); -} - /* * Delete a list entry by making the prev/next entries * point to each other. @@ -194,69 +107,6 @@ static inline void list_del(struct list_head *entry) entry->prev = LIST_POISON2; } -/** - * list_del_rcu - deletes entry from list without re-initialization - * @entry: the element to delete from the list. - * - * Note: list_empty on entry does not return true after this, - * the entry is in an undefined state. It is useful for RCU based - * lockfree traversal. - * - * In particular, it means that we can not poison the forward - * pointers that may still be used for walking the list. - * - * The caller must take whatever precautions are necessary - * (such as holding appropriate locks) to avoid racing - * with another list-mutation primitive, such as list_del_rcu() - * or list_add_rcu(), running on this same list. - * However, it is perfectly legal to run concurrently with - * the _rcu list-traversal primitives, such as - * list_for_each_entry_rcu(). - * - * Note that the caller is not permitted to immediately free - * the newly deleted entry. Instead, either synchronize_kernel() - * or call_rcu() must be used to defer freeing until an RCU - * grace period has elapsed. - */ -static inline void list_del_rcu(struct list_head *entry) -{ - __list_del(entry->prev, entry->next); - entry->prev = LIST_POISON2; -} - -/** - * list_del_init - deletes entry from list and reinitialize it. - * @entry: the element to delete from the list. - */ -static inline void list_del_init(struct list_head *entry) -{ - __list_del(entry->prev, entry->next); - INIT_LIST_HEAD(entry); -} - -/** - * list_move - delete from one list and add as another's head - * @list: the entry to move - * @head: the head that will precede our entry - */ -static inline void list_move(struct list_head *list, struct list_head *head) -{ - __list_del(list->prev, list->next); - list_add(list, head); -} - -/** - * list_move_tail - delete from one list and add as another's tail - * @list: the entry to move - * @head: the head that will follow our entry - */ -static inline void list_move_tail(struct list_head *list, - struct list_head *head) -{ - __list_del(list->prev, list->next); - list_add_tail(list, head); -} - /** * list_empty - tests whether a list is empty * @head: the list to test. @@ -265,66 +115,6 @@ static inline int list_empty(const struct list_head *head) { return head->next == head; } - -/** - * list_empty_careful - tests whether a list is - * empty _and_ checks that no other CPU might be - * in the process of still modifying either member - * - * NOTE: using list_empty_careful() without synchronization - * can only be safe if the only activity that can happen - * to the list entry is list_del_init(). Eg. it cannot be used - * if another CPU could re-list_add() it. - * - * @head: the list to test. - */ -static inline int list_empty_careful(const struct list_head *head) -{ - struct list_head *next = head->next; - return (next == head) && (next == head->prev); -} - -static inline void __list_splice(struct list_head *list, - struct list_head *head) -{ - struct list_head *first = list->next; - struct list_head *last = list->prev; - struct list_head *at = head->next; - - first->prev = head; - head->next = first; - - last->next = at; - at->prev = last; -} - -/** - * list_splice - join two lists - * @list: the new list to add. - * @head: the place to add it in the first list. - */ -static inline void list_splice(struct list_head *list, struct list_head *head) -{ - if (!list_empty(list)) - __list_splice(list, head); -} - -/** - * list_splice_init - join two lists and reinitialise the emptied list. - * @list: the new list to add. - * @head: the place to add it in the first list. - * - * The list at @list is reinitialised - */ -static inline void list_splice_init(struct list_head *list, - struct list_head *head) -{ - if (!list_empty(list)) { - __list_splice(list, head); - INIT_LIST_HEAD(list); - } -} - /** * list_entry - get the struct for this entry * @ptr: the &struct list_head pointer. @@ -334,47 +124,6 @@ static inline void list_splice_init(struct list_head *list, #define list_entry(ptr, type, member) \ container_of(ptr, type, member) -/** - * list_for_each - iterate over a list - * @pos: the &struct list_head to use as a loop counter. - * @head: the head for your list. - */ -#define list_for_each(pos, head) \ - for (pos = (head)->next, prefetch(pos->next); pos != (head); \ - pos = pos->next, prefetch(pos->next)) - -/** - * __list_for_each - iterate over a list - * @pos: the &struct list_head to use as a loop counter. - * @head: the head for your list. - * - * This variant differs from list_for_each() in that it's the - * simplest possible list iteration code, no prefetching is done. - * Use this for code that knows the list to be very short (empty - * or 1 entry) most of the time. - */ -#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 counter. - * @head: the head for your list. - */ -#define list_for_each_prev(pos, head) \ - for (pos = (head)->prev, prefetch(pos->prev); pos != (head); \ - pos = pos->prev, prefetch(pos->prev)) - -/** - * list_for_each_safe - iterate over a list safe against removal of list entry - * @pos: the &struct list_head to use as a loop counter. - * @n: another &struct list_head to use as temporary storage - * @head: the head for your list. - */ -#define list_for_each_safe(pos, n, head) \ - for (pos = (head)->next, n = pos->next; pos != (head); \ - pos = n, n = pos->next) - /** * list_for_each_entry - iterate over list of given type * @pos: the type * to use as a loop counter. @@ -388,43 +137,6 @@ static inline void list_splice_init(struct list_head *list, pos = list_entry(pos->member.next, typeof(*pos), member), \ prefetch(pos->member.next)) -/** - * list_for_each_entry_reverse - iterate backwards over list of given type. - * @pos: the type * to use as a loop counter. - * @head: the head for your 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), \ - prefetch(pos->member.prev); \ - &pos->member != (head); \ - pos = list_entry(pos->member.prev, typeof(*pos), member), \ - prefetch(pos->member.prev)) - -/** - * list_prepare_entry - prepare a pos entry for use as a start point 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. - */ -#define list_prepare_entry(pos, head, member) \ - ((pos) ? : list_entry(head, typeof(*pos), member)) - -/** - * list_for_each_entry_continue - iterate over list of given type - * continuing after existing point - * @pos: the type * to use as a loop counter. - * @head: the head for your list. - * @member: the name of the list_struct within the struct. - */ -#define list_for_each_entry_continue(pos, head, member) \ - for (pos = list_entry(pos->member.next, typeof(*pos), member), \ - prefetch(pos->member.next); \ - &pos->member != (head); \ - pos = list_entry(pos->member.next, typeof(*pos), member), \ - prefetch(pos->member.next)) - /** * 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 counter. @@ -438,290 +150,4 @@ static inline void list_splice_init(struct list_head *list, &pos->member != (head); \ pos = n, n = list_entry(n->member.next, typeof(*n), member)) -/** - * list_for_each_rcu - iterate over an rcu-protected list - * @pos: the &struct list_head to use as a loop counter. - * @head: the head for your list. - * - * This list-traversal primitive may safely run concurrently with - * the _rcu list-mutation primitives such as list_add_rcu() - * as long as the traversal is guarded by rcu_read_lock(). - */ -#define list_for_each_rcu(pos, head) \ - for (pos = (head)->next, prefetch(pos->next); pos != (head); \ - pos = pos->next, ({ smp_read_barrier_depends(); 0;}), prefetch(pos->next)) - -#define __list_for_each_rcu(pos, head) \ - for (pos = (head)->next; pos != (head); \ - pos = pos->next, ({ smp_read_barrier_depends(); 0;})) - -/** - * list_for_each_safe_rcu - iterate over an rcu-protected list safe - * against removal of list entry - * @pos: the &struct list_head to use as a loop counter. - * @n: another &struct list_head to use as temporary storage - * @head: the head for your list. - * - * This list-traversal primitive may safely run concurrently with - * the _rcu list-mutation primitives such as list_add_rcu() - * as long as the traversal is guarded by rcu_read_lock(). - */ -#define list_for_each_safe_rcu(pos, n, head) \ - for (pos = (head)->next, n = pos->next; pos != (head); \ - pos = n, ({ smp_read_barrier_depends(); 0;}), n = pos->next) - -/** - * list_for_each_entry_rcu - iterate over rcu list of given type - * @pos: the type * to use as a loop counter. - * @head: the head for your list. - * @member: the name of the list_struct within the struct. - * - * This list-traversal primitive may safely run concurrently with - * the _rcu list-mutation primitives such as list_add_rcu() - * as long as the traversal is guarded by rcu_read_lock(). - */ -#define list_for_each_entry_rcu(pos, head, member) \ - for (pos = list_entry((head)->next, typeof(*pos), member), \ - prefetch(pos->member.next); \ - &pos->member != (head); \ - pos = list_entry(pos->member.next, typeof(*pos), member), \ - ({ smp_read_barrier_depends(); 0;}), \ - prefetch(pos->member.next)) - - -/** - * list_for_each_continue_rcu - iterate over an rcu-protected list - * continuing after existing point. - * @pos: the &struct list_head to use as a loop counter. - * @head: the head for your list. - * - * This list-traversal primitive may safely run concurrently with - * the _rcu list-mutation primitives such as list_add_rcu() - * as long as the traversal is guarded by rcu_read_lock(). - */ -#define list_for_each_continue_rcu(pos, head) \ - for ((pos) = (pos)->next, prefetch((pos)->next); (pos) != (head); \ - (pos) = (pos)->next, ({ smp_read_barrier_depends(); 0;}), prefetch((pos)->next)) - -/* - * Double linked lists with a single pointer list head. - * Mostly useful for hash tables where the two pointer list head is - * too wasteful. - * You lose the ability to access the tail in O(1). - */ - -struct hlist_head { - struct hlist_node *first; -}; - -struct hlist_node { - struct hlist_node *next, **pprev; -}; - -#define HLIST_HEAD_INIT { .first = NULL } -#define HLIST_HEAD(name) struct hlist_head name = { .first = NULL } -#define INIT_HLIST_HEAD(ptr) ((ptr)->first = NULL) -#define INIT_HLIST_NODE(ptr) ((ptr)->next = NULL, (ptr)->pprev = NULL) - -static inline int hlist_unhashed(const struct hlist_node *h) -{ - return !h->pprev; -} - -static inline int hlist_empty(const struct hlist_head *h) -{ - return !h->first; -} - -static inline void __hlist_del(struct hlist_node *n) -{ - struct hlist_node *next = n->next; - struct hlist_node **pprev = n->pprev; - *pprev = next; - if (next) - next->pprev = pprev; -} - -static inline void hlist_del(struct hlist_node *n) -{ - __hlist_del(n); - n->next = LIST_POISON1; - n->pprev = LIST_POISON2; -} - -/** - * hlist_del_rcu - deletes entry from hash list without re-initialization - * @n: the element to delete from the hash list. - * - * Note: list_unhashed() on entry does not return true after this, - * the entry is in an undefined state. It is useful for RCU based - * lockfree traversal. - * - * In particular, it means that we can not poison the forward - * pointers that may still be used for walking the hash list. - * - * The caller must take whatever precautions are necessary - * (such as holding appropriate locks) to avoid racing - * with another list-mutation primitive, such as hlist_add_head_rcu() - * or hlist_del_rcu(), running on this same list. - * However, it is perfectly legal to run concurrently with - * the _rcu list-traversal primitives, such as - * hlist_for_each_entry(). - */ -static inline void hlist_del_rcu(struct hlist_node *n) -{ - __hlist_del(n); - n->pprev = LIST_POISON2; -} - -static inline void hlist_del_init(struct hlist_node *n) -{ - if (n->pprev) { - __hlist_del(n); - INIT_HLIST_NODE(n); - } -} - -#define hlist_del_rcu_init hlist_del_init - -static inline void hlist_add_head(struct hlist_node *n, struct hlist_head *h) -{ - struct hlist_node *first = h->first; - n->next = first; - if (first) - first->pprev = &n->next; - h->first = n; - n->pprev = &h->first; -} - - -/** - * hlist_add_head_rcu - adds the specified element to the specified hlist, - * while permitting racing traversals. - * @n: the element to add to the hash list. - * @h: the list to add to. - * - * The caller must take whatever precautions are necessary - * (such as holding appropriate locks) to avoid racing - * with another list-mutation primitive, such as hlist_add_head_rcu() - * or hlist_del_rcu(), running on this same list. - * However, it is perfectly legal to run concurrently with - * the _rcu list-traversal primitives, such as - * hlist_for_each_entry(), but only if smp_read_barrier_depends() - * is used to prevent memory-consistency problems on Alpha CPUs. - * Regardless of the type of CPU, the list-traversal primitive - * must be guarded by rcu_read_lock(). - * - * OK, so why don't we have an hlist_for_each_entry_rcu()??? - */ -static inline void hlist_add_head_rcu(struct hlist_node *n, - struct hlist_head *h) -{ - struct hlist_node *first = h->first; - n->next = first; - n->pprev = &h->first; - smp_wmb(); - if (first) - first->pprev = &n->next; - h->first = n; -} - -/* next must be != NULL */ -static inline void hlist_add_before(struct hlist_node *n, - struct hlist_node *next) -{ - n->pprev = next->pprev; - n->next = next; - next->pprev = &n->next; - *(n->pprev) = n; -} - -static inline void hlist_add_after(struct hlist_node *n, - struct hlist_node *next) -{ - next->next = n->next; - n->next = next; - next->pprev = &n->next; - - if(next->next) - next->next->pprev = &next->next; -} - -#define hlist_entry(ptr, type, member) container_of(ptr,type,member) - -#define hlist_for_each(pos, head) \ - for (pos = (head)->first; pos && ({ prefetch(pos->next); 1; }); \ - pos = pos->next) - -#define hlist_for_each_safe(pos, n, head) \ - for (pos = (head)->first; pos && ({ n = pos->next; 1; }); \ - pos = n) - -/** - * hlist_for_each_entry - iterate over list of given type - * @tpos: the type * to use as a loop counter. - * @pos: the &struct hlist_node to use as a loop counter. - * @head: the head for your list. - * @member: the name of the hlist_node within the struct. - */ -#define hlist_for_each_entry(tpos, pos, head, member) \ - for (pos = (head)->first; \ - pos && ({ prefetch(pos->next); 1;}) && \ - ({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \ - pos = pos->next) - -/** - * hlist_for_each_entry_continue - iterate over a hlist continuing after existing point - * @tpos: the type * to use as a loop counter. - * @pos: the &struct hlist_node to use as a loop counter. - * @member: the name of the hlist_node within the struct. - */ -#define hlist_for_each_entry_continue(tpos, pos, member) \ - for (pos = (pos)->next; \ - pos && ({ prefetch(pos->next); 1;}) && \ - ({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \ - pos = pos->next) - -/** - * hlist_for_each_entry_from - iterate over a hlist continuing from existing point - * @tpos: the type * to use as a loop counter. - * @pos: the &struct hlist_node to use as a loop counter. - * @member: the name of the hlist_node within the struct. - */ -#define hlist_for_each_entry_from(tpos, pos, member) \ - for (; pos && ({ prefetch(pos->next); 1;}) && \ - ({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \ - pos = pos->next) - -/** - * hlist_for_each_entry_safe - iterate over list of given type safe against removal of list entry - * @tpos: the type * to use as a loop counter. - * @pos: the &struct hlist_node to use as a loop counter. - * @n: another &struct hlist_node to use as temporary storage - * @head: the head for your list. - * @member: the name of the hlist_node within the struct. - */ -#define hlist_for_each_entry_safe(tpos, pos, n, head, member) \ - for (pos = (head)->first; \ - pos && ({ n = pos->next; 1; }) && \ - ({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \ - pos = n) - -/** - * hlist_for_each_entry_rcu - iterate over rcu list of given type - * @pos: the type * to use as a loop counter. - * @pos: the &struct hlist_node to use as a loop counter. - * @head: the head for your list. - * @member: the name of the hlist_node within the struct. - * - * This list-traversal primitive may safely run concurrently with - * the _rcu list-mutation primitives such as hlist_add_rcu() - * as long as the traversal is guarded by rcu_read_lock(). - */ -#define hlist_for_each_entry_rcu(tpos, pos, head, member) \ - for (pos = (head)->first; \ - pos && ({ prefetch(pos->next); 1;}) && \ - ({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \ - pos = pos->next, ({ smp_read_barrier_depends(); 0; }) ) - #endif -- 2.35.8