linux/include/linux/rhashtable-types.h

/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Resizable, Scalable, Concurrent Hash Table
 *
 * Simple structures that might be needed in include
 * files.
 */

#ifndef _LINUX_RHASHTABLE_TYPES_H
#define _LINUX_RHASHTABLE_TYPES_H

#include <linux/alloc_tag.h>
#include <linux/atomic.h>
#include <linux/compiler.h>
#include <linux/mutex.h>
#include <linux/workqueue_types.h>

struct rhash_head { … };

struct rhlist_head { … };

struct bucket_table;

/**
 * struct rhashtable_compare_arg - Key for the function rhashtable_compare
 * @ht: Hash table
 * @key: Key to compare against
 */
struct rhashtable_compare_arg { … };

rht_hashfn_t;
rht_obj_hashfn_t;
rht_obj_cmpfn_t;

/**
 * struct rhashtable_params - Hash table construction parameters
 * @nelem_hint: Hint on number of elements, should be 75% of desired size
 * @key_len: Length of key
 * @key_offset: Offset of key in struct to be hashed
 * @head_offset: Offset of rhash_head in struct to be hashed
 * @max_size: Maximum size while expanding
 * @min_size: Minimum size while shrinking
 * @automatic_shrinking: Enable automatic shrinking of tables
 * @hashfn: Hash function (default: jhash2 if !(key_len % 4), or jhash)
 * @obj_hashfn: Function to hash object
 * @obj_cmpfn: Function to compare key with object
 */
struct rhashtable_params { … };

/**
 * struct rhashtable - Hash table handle
 * @tbl: Bucket table
 * @key_len: Key length for hashfn
 * @max_elems: Maximum number of elements in table
 * @p: Configuration parameters
 * @rhlist: True if this is an rhltable
 * @run_work: Deferred worker to expand/shrink asynchronously
 * @mutex: Mutex to protect current/future table swapping
 * @lock: Spin lock to protect walker list
 * @nelems: Number of elements in table
 */
struct rhashtable { … };

/**
 * struct rhltable - Hash table with duplicate objects in a list
 * @ht: Underlying rhtable
 */
struct rhltable { … };

/**
 * struct rhashtable_walker - Hash table walker
 * @list: List entry on list of walkers
 * @tbl: The table that we were walking over
 */
struct rhashtable_walker { … };

/**
 * struct rhashtable_iter - Hash table iterator
 * @ht: Table to iterate through
 * @p: Current pointer
 * @list: Current hash list pointer
 * @walker: Associated rhashtable walker
 * @slot: Current slot
 * @skip: Number of entries to skip in slot
 */
struct rhashtable_iter { … };

int rhashtable_init_noprof(struct rhashtable *ht,
		    const struct rhashtable_params *params);
#define rhashtable_init(...) …

int rhltable_init_noprof(struct rhltable *hlt,
		  const struct rhashtable_params *params);
#define rhltable_init(...) …

#endif /* _LINUX_RHASHTABLE_TYPES_H */