511 lines
15 KiB
C
511 lines
15 KiB
C
#ifndef __LINUX_LIST_WRAPPER_H
|
|
#define __LINUX_LIST_WRAPPER_H
|
|
|
|
#ifdef __KERNEL__
|
|
|
|
#include_next <linux/list.h>
|
|
#include <asm/system.h>
|
|
|
|
#define LIST_POISON1 ((void *) 0x00100100)
|
|
#define LIST_POISON2 ((void *) 0x00200200)
|
|
|
|
/*
|
|
* 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);
|
|
}
|
|
|
|
/**
|
|
* 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_rcu()
|
|
* 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_replace_rcu - replace old entry by new one
|
|
* @old : the element to be replaced
|
|
* @new : the new element to insert
|
|
*
|
|
* The @old entry will be replaced with the @new entry atomically.
|
|
* Note: @old should not be empty.
|
|
*/
|
|
static inline void list_replace_rcu(struct list_head *old,
|
|
struct list_head *new)
|
|
{
|
|
new->next = old->next;
|
|
new->prev = old->prev;
|
|
smp_wmb();
|
|
new->next->prev = new;
|
|
new->prev->next = new;
|
|
old->prev = LIST_POISON2;
|
|
}
|
|
/**
|
|
* list_for_each_rcu - iterate over an rcu-protected list
|
|
* @pos: the &struct list_head to use as a loop cursor.
|
|
* @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(rcu_dereference(pos)->next), pos != (head); \
|
|
pos = pos->next)
|
|
|
|
#define __list_for_each_rcu(pos, head) \
|
|
for (pos = (head)->next; \
|
|
rcu_dereference(pos) != (head); \
|
|
pos = pos->next)
|
|
|
|
/**
|
|
* list_for_each_safe_rcu
|
|
* @pos: the &struct list_head to use as a loop cursor.
|
|
* @n: another &struct list_head to use as temporary storage
|
|
* @head: the head for your list.
|
|
*
|
|
* Iterate over an rcu-protected list, safe against removal of list entry.
|
|
*
|
|
* 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 = rcu_dereference(pos)->next, pos != (head); \
|
|
pos = n)
|
|
|
|
/**
|
|
* list_for_each_entry_rcu - iterate over rcu 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.
|
|
*
|
|
* 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(rcu_dereference(pos)->member.next), \
|
|
&pos->member != (head); \
|
|
pos = list_entry(pos->member.next, typeof(*pos), member))
|
|
|
|
|
|
/**
|
|
* list_for_each_continue_rcu
|
|
* @pos: the &struct list_head to use as a loop cursor.
|
|
* @head: the head for your list.
|
|
*
|
|
* Iterate over an rcu-protected list, continuing after current point.
|
|
*
|
|
* 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(rcu_dereference((pos))->next), (pos) != (head); \
|
|
(pos) = (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)
|
|
static inline void INIT_HLIST_NODE(struct hlist_node *h)
|
|
{
|
|
h->next = NULL;
|
|
h->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 (!hlist_unhashed(n)) {
|
|
__hlist_del(n);
|
|
INIT_HLIST_NODE(n);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* hlist_replace_rcu - replace old entry by new one
|
|
* @old : the element to be replaced
|
|
* @new : the new element to insert
|
|
*
|
|
* The @old entry will be replaced with the @new entry atomically.
|
|
*/
|
|
static inline void hlist_replace_rcu(struct hlist_node *old,
|
|
struct hlist_node *new)
|
|
{
|
|
struct hlist_node *next = old->next;
|
|
|
|
new->next = next;
|
|
new->pprev = old->pprev;
|
|
smp_wmb();
|
|
if (next)
|
|
new->next->pprev = &new->next;
|
|
*new->pprev = new;
|
|
old->pprev = LIST_POISON2;
|
|
}
|
|
|
|
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
|
|
* @n: the element to add to the hash list.
|
|
* @h: the list to add to.
|
|
*
|
|
* Description:
|
|
* Adds the specified element to the specified hlist,
|
|
* while permitting racing traversals.
|
|
*
|
|
* 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_rcu(), 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().
|
|
*/
|
|
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;
|
|
}
|
|
|
|
/**
|
|
* hlist_add_before_rcu
|
|
* @n: the new element to add to the hash list.
|
|
* @next: the existing element to add the new element before.
|
|
*
|
|
* Description:
|
|
* Adds the specified element to the specified hlist
|
|
* before the specified node while permitting racing traversals.
|
|
*
|
|
* 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_rcu(), used to prevent memory-consistency
|
|
* problems on Alpha CPUs.
|
|
*/
|
|
static inline void hlist_add_before_rcu(struct hlist_node *n,
|
|
struct hlist_node *next)
|
|
{
|
|
n->pprev = next->pprev;
|
|
n->next = next;
|
|
smp_wmb();
|
|
next->pprev = &n->next;
|
|
*(n->pprev) = n;
|
|
}
|
|
|
|
/**
|
|
* hlist_add_after_rcu
|
|
* @prev: the existing element to add the new element after.
|
|
* @n: the new element to add to the hash list.
|
|
*
|
|
* Description:
|
|
* Adds the specified element to the specified hlist
|
|
* after the specified node while permitting racing traversals.
|
|
*
|
|
* 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_rcu(), used to prevent memory-consistency
|
|
* problems on Alpha CPUs.
|
|
*/
|
|
static inline void hlist_add_after_rcu(struct hlist_node *prev,
|
|
struct hlist_node *n)
|
|
{
|
|
n->next = prev->next;
|
|
n->pprev = &prev->next;
|
|
smp_wmb();
|
|
prev->next = n;
|
|
if (n->next)
|
|
n->next->pprev = &n->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 cursor.
|
|
* @pos: the &struct hlist_node to use as a loop cursor.
|
|
* @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 current point
|
|
* @tpos: the type * to use as a loop cursor.
|
|
* @pos: the &struct hlist_node to use as a loop cursor.
|
|
* @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 current point
|
|
* @tpos: the type * to use as a loop cursor.
|
|
* @pos: the &struct hlist_node to use as a loop cursor.
|
|
* @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 cursor.
|
|
* @pos: the &struct hlist_node to use as a loop cursor.
|
|
* @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
|
|
* @tpos: the type * to use as a loop cursor.
|
|
* @pos: the &struct hlist_node to use as a loop cursor.
|
|
* @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_head_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; \
|
|
rcu_dereference(pos) && ({ prefetch(pos->next); 1;}) && \
|
|
({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \
|
|
pos = pos->next)
|
|
|
|
|
|
#if LINUX_VERSION_CODE < KERNEL_VERSION(2,4,23)
|
|
/**
|
|
* list_for_each_entry_safe - iterate over list of given type safe against remov
|
|
al of list entry
|
|
* @pos: the type * to use as a loop counter.
|
|
* @n: another type * to use as temporary storage
|
|
* @head: the head for your 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); \
|
|
&pos->member != (head); \
|
|
pos = n, n = list_entry(n->member.next, typeof(*n), member))
|
|
#endif /* linux kernel < 2.4.23 */
|
|
|
|
|
|
#else
|
|
#warning "don't include kernel headers in userspace"
|
|
#endif /* __KERNEL__ */
|
|
#endif
|