include/linux/assoc_array_priv.h

Source file repositories/reference/linux-study-clean/include/linux/assoc_array_priv.h

File Facts

System
Linux kernel
Corpus path
include/linux/assoc_array_priv.h
Extension
.h
Size
5423 bytes
Lines
179
Domain
Core OS
Bucket
Core Kernel Interface
Inferred role
Core OS: implementation source
Status
source implementation candidate

Why This File Exists

Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.

Dependency Surface

Detected Declarations

Annotated Snippet

struct assoc_array_node {
	struct assoc_array_ptr	*back_pointer;
	u8			parent_slot;
	struct assoc_array_ptr	*slots[ASSOC_ARRAY_FAN_OUT];
	unsigned long		nr_leaves_on_branch;
};

/*
 * A shortcut through the index space out to where a collection of nodes/leaves
 * with the same IDs live.
 */
struct assoc_array_shortcut {
	struct assoc_array_ptr	*back_pointer;
	int			parent_slot;
	int			skip_to_level;
	struct assoc_array_ptr	*next_node;
	unsigned long		index_key[];
};

/*
 * Preallocation cache.
 */
struct assoc_array_edit {
	struct rcu_head			rcu;
	struct assoc_array		*array;
	const struct assoc_array_ops	*ops;
	const struct assoc_array_ops	*ops_for_excised_subtree;
	struct assoc_array_ptr		*leaf;
	struct assoc_array_ptr		**leaf_p;
	struct assoc_array_ptr		*dead_leaf;
	struct assoc_array_ptr		*new_meta[3];
	struct assoc_array_ptr		*excised_meta[1];
	struct assoc_array_ptr		*excised_subtree;
	struct assoc_array_ptr		**set_backpointers[ASSOC_ARRAY_FAN_OUT];
	struct assoc_array_ptr		*set_backpointers_to;
	struct assoc_array_node		*adjust_count_on;
	long				adjust_count_by;
	struct {
		struct assoc_array_ptr	**ptr;
		struct assoc_array_ptr	*to;
	} set[2];
	struct {
		u8			*p;
		u8			to;
	} set_parent_slot[1];
	u8				segment_cache[ASSOC_ARRAY_FAN_OUT + 1];
};

/*
 * Internal tree member pointers are marked in the bottom one or two bits to
 * indicate what type they are so that we don't have to look behind every
 * pointer to see what it points to.
 *
 * We provide functions to test type annotations and to create and translate
 * the annotated pointers.
 */
#define ASSOC_ARRAY_PTR_TYPE_MASK 0x1UL
#define ASSOC_ARRAY_PTR_LEAF_TYPE 0x0UL	/* Points to leaf (or nowhere) */
#define ASSOC_ARRAY_PTR_META_TYPE 0x1UL	/* Points to node or shortcut */
#define ASSOC_ARRAY_PTR_SUBTYPE_MASK	0x2UL
#define ASSOC_ARRAY_PTR_NODE_SUBTYPE	0x0UL
#define ASSOC_ARRAY_PTR_SHORTCUT_SUBTYPE 0x2UL

static inline bool assoc_array_ptr_is_meta(const struct assoc_array_ptr *x)
{
	return (unsigned long)x & ASSOC_ARRAY_PTR_TYPE_MASK;
}
static inline bool assoc_array_ptr_is_leaf(const struct assoc_array_ptr *x)
{
	return !assoc_array_ptr_is_meta(x);
}
static inline bool assoc_array_ptr_is_shortcut(const struct assoc_array_ptr *x)
{
	return (unsigned long)x & ASSOC_ARRAY_PTR_SUBTYPE_MASK;
}
static inline bool assoc_array_ptr_is_node(const struct assoc_array_ptr *x)
{
	return !assoc_array_ptr_is_shortcut(x);
}

static inline void *assoc_array_ptr_to_leaf(const struct assoc_array_ptr *x)
{
	return (void *)((unsigned long)x & ~ASSOC_ARRAY_PTR_TYPE_MASK);
}

static inline
unsigned long __assoc_array_ptr_to_meta(const struct assoc_array_ptr *x)
{
	return (unsigned long)x &
		~(ASSOC_ARRAY_PTR_SUBTYPE_MASK | ASSOC_ARRAY_PTR_TYPE_MASK);

Annotation

Implementation Notes