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authorKent Overstreet <kent.overstreet@linux.dev>2024-01-16 17:00:02 -0500
committerKent Overstreet <kent.overstreet@linux.dev>2024-01-16 17:17:23 -0500
commitb5fd066153c40a70a29caa1ea7987723ab687763 (patch)
tree6d43a8b0a90d549a54c65565ac96c92b3e84b594 /c_src/include/linux/list_nulls.h
parent06ff8b55b70fda44d91b31b5511fafd1680a8934 (diff)
Move c_src dirs back to toplevel
We just wanted c sourcefiles out of the top level, not c source directories. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Diffstat (limited to 'c_src/include/linux/list_nulls.h')
-rw-r--r--c_src/include/linux/list_nulls.h145
1 files changed, 0 insertions, 145 deletions
diff --git a/c_src/include/linux/list_nulls.h b/c_src/include/linux/list_nulls.h
deleted file mode 100644
index fa6e8471..00000000
--- a/c_src/include/linux/list_nulls.h
+++ /dev/null
@@ -1,145 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _LINUX_LIST_NULLS_H
-#define _LINUX_LIST_NULLS_H
-
-#include <linux/poison.h>
-#include <linux/const.h>
-
-/*
- * Special version of lists, where end of list is not a NULL pointer,
- * but a 'nulls' marker, which can have many different values.
- * (up to 2^31 different values guaranteed on all platforms)
- *
- * In the standard hlist, termination of a list is the NULL pointer.
- * In this special 'nulls' variant, we use the fact that objects stored in
- * a list are aligned on a word (4 or 8 bytes alignment).
- * We therefore use the last significant bit of 'ptr' :
- * Set to 1 : This is a 'nulls' end-of-list marker (ptr >> 1)
- * Set to 0 : This is a pointer to some object (ptr)
- */
-
-struct hlist_nulls_head {
- struct hlist_nulls_node *first;
-};
-
-struct hlist_nulls_node {
- struct hlist_nulls_node *next, **pprev;
-};
-#define NULLS_MARKER(value) (1UL | (((long)value) << 1))
-#define INIT_HLIST_NULLS_HEAD(ptr, nulls) \
- ((ptr)->first = (struct hlist_nulls_node *) NULLS_MARKER(nulls))
-
-#define hlist_nulls_entry(ptr, type, member) container_of(ptr,type,member)
-
-#define hlist_nulls_entry_safe(ptr, type, member) \
- ({ typeof(ptr) ____ptr = (ptr); \
- !is_a_nulls(____ptr) ? hlist_nulls_entry(____ptr, type, member) : NULL; \
- })
-/**
- * ptr_is_a_nulls - Test if a ptr is a nulls
- * @ptr: ptr to be tested
- *
- */
-static inline int is_a_nulls(const struct hlist_nulls_node *ptr)
-{
- return ((unsigned long)ptr & 1);
-}
-
-/**
- * get_nulls_value - Get the 'nulls' value of the end of chain
- * @ptr: end of chain
- *
- * Should be called only if is_a_nulls(ptr);
- */
-static inline unsigned long get_nulls_value(const struct hlist_nulls_node *ptr)
-{
- return ((unsigned long)ptr) >> 1;
-}
-
-/**
- * hlist_nulls_unhashed - Has node been removed and reinitialized?
- * @h: Node to be checked
- *
- * Not that not all removal functions will leave a node in unhashed state.
- * For example, hlist_del_init_rcu() leaves the node in unhashed state,
- * but hlist_nulls_del() does not.
- */
-static inline int hlist_nulls_unhashed(const struct hlist_nulls_node *h)
-{
- return !h->pprev;
-}
-
-/**
- * hlist_nulls_unhashed_lockless - Has node been removed and reinitialized?
- * @h: Node to be checked
- *
- * Not that not all removal functions will leave a node in unhashed state.
- * For example, hlist_del_init_rcu() leaves the node in unhashed state,
- * but hlist_nulls_del() does not. Unlike hlist_nulls_unhashed(), this
- * function may be used locklessly.
- */
-static inline int hlist_nulls_unhashed_lockless(const struct hlist_nulls_node *h)
-{
- return !READ_ONCE(h->pprev);
-}
-
-static inline int hlist_nulls_empty(const struct hlist_nulls_head *h)
-{
- return is_a_nulls(READ_ONCE(h->first));
-}
-
-static inline void hlist_nulls_add_head(struct hlist_nulls_node *n,
- struct hlist_nulls_head *h)
-{
- struct hlist_nulls_node *first = h->first;
-
- n->next = first;
- WRITE_ONCE(n->pprev, &h->first);
- h->first = n;
- if (!is_a_nulls(first))
- WRITE_ONCE(first->pprev, &n->next);
-}
-
-static inline void __hlist_nulls_del(struct hlist_nulls_node *n)
-{
- struct hlist_nulls_node *next = n->next;
- struct hlist_nulls_node **pprev = n->pprev;
-
- WRITE_ONCE(*pprev, next);
- if (!is_a_nulls(next))
- WRITE_ONCE(next->pprev, pprev);
-}
-
-static inline void hlist_nulls_del(struct hlist_nulls_node *n)
-{
- __hlist_nulls_del(n);
- WRITE_ONCE(n->pprev, LIST_POISON2);
-}
-
-/**
- * hlist_nulls_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_nulls_for_each_entry(tpos, pos, head, member) \
- for (pos = (head)->first; \
- (!is_a_nulls(pos)) && \
- ({ tpos = hlist_nulls_entry(pos, typeof(*tpos), member); 1;}); \
- pos = pos->next)
-
-/**
- * hlist_nulls_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_nulls_for_each_entry_from(tpos, pos, member) \
- for (; (!is_a_nulls(pos)) && \
- ({ tpos = hlist_nulls_entry(pos, typeof(*tpos), member); 1;}); \
- pos = pos->next)
-
-#endif