/* SPDX-License-Identifier: BSD-3-Clause
 * Copyright 2019 Mellanox Technologies, Ltd
 */

#ifndef RTE_PMD_MLX5_COMMON_UTILS_H_
#define RTE_PMD_MLX5_COMMON_UTILS_H_

#include <rte_rwlock.h>

#include "mlx5_common.h"

/************************ mlx5 list *****************************/

/** Maximum size of string for naming. */
#define MLX5_NAME_SIZE			32
/** Maximum size of list. */
#define MLX5_LIST_MAX			(RTE_MAX_LCORE + 2)
/** Global list index. */
#define MLX5_LIST_GLOBAL		((MLX5_LIST_MAX) - 1)
/** None rte core list index. */
#define MLX5_LIST_NLCORE		((MLX5_LIST_MAX) - 2)

struct mlx5_list;

/**
 * Structure of the entry in the mlx5 list, user should define its own struct
 * that contains this in order to store the data.
 */
struct mlx5_list_entry {
	LIST_ENTRY(mlx5_list_entry) next; /* Entry pointers in the list. */
	uint32_t ref_cnt __rte_aligned(8); /* 0 means, entry is invalid. */
	uint32_t lcore_idx;
	union {
		struct mlx5_list_entry *gentry;
		uint32_t bucket_idx;
	};
} __rte_packed;

struct mlx5_list_cache {
	LIST_HEAD(mlx5_list_head, mlx5_list_entry) h;
	uint32_t inv_cnt; /* Invalid entries counter. */
} __rte_cache_aligned;

/**
 * Type of callback function for entry removal.
 *
 * @param tool_ctx
 *   The tool instance user context.
 * @param entry
 *   The entry in the list.
 */
typedef void (*mlx5_list_remove_cb)(void *tool_ctx,
				    struct mlx5_list_entry *entry);

/**
 * Type of function for user defined matching.
 *
 * @param tool_ctx
 *   The tool instance context.
 * @param entry
 *   The entry in the list.
 * @param ctx
 *   The pointer to new entry context.
 *
 * @return
 *   0 if matching, non-zero number otherwise.
 */
typedef int (*mlx5_list_match_cb)(void *tool_ctx,
				   struct mlx5_list_entry *entry, void *ctx);

typedef struct mlx5_list_entry *(*mlx5_list_clone_cb)(void *tool_ctx,
				      struct mlx5_list_entry *entry, void *ctx);

typedef void (*mlx5_list_clone_free_cb)(void *tool_ctx,
					struct mlx5_list_entry *entry);

/**
 * Type of function for user defined mlx5 list entry creation.
 *
 * @param tool_ctx
 *   The mlx5 tool instance context.
 * @param ctx
 *   The pointer to new entry context.
 *
 * @return
 *   Pointer of entry on success, NULL otherwise.
 */
typedef struct mlx5_list_entry *(*mlx5_list_create_cb)(void *tool_ctx,
						       void *ctx);

/**
 * Linked mlx5 list constant object.
 */
struct mlx5_list_const {
	char name[MLX5_NAME_SIZE]; /**< Name of the mlx5 list. */
	void *ctx; /* user objects target to callback. */
	bool lcores_share; /* Whether to share objects between the lcores. */
	rte_spinlock_t lcore_lock; /* Lock for non-lcore list. */
	mlx5_list_create_cb cb_create; /**< entry create callback. */
	mlx5_list_match_cb cb_match; /**< entry match callback. */
	mlx5_list_remove_cb cb_remove; /**< entry remove callback. */
	mlx5_list_clone_cb cb_clone; /**< entry clone callback. */
	mlx5_list_clone_free_cb cb_clone_free;
	/**< entry clone free callback. */
};

/**
 * Linked mlx5 list inconstant data.
 */
struct mlx5_list_inconst {
	rte_rwlock_t lock; /* read/write lock. */
	volatile uint32_t gen_cnt; /* List modification may update it. */
	volatile uint32_t count; /* number of entries in list. */
	struct mlx5_list_cache *cache[MLX5_LIST_MAX];
	/* Lcore cache, last index is the global cache. */
};

/**
 * Linked mlx5 list structure.
 *
 * Entry in mlx5 list could be reused if entry already exists,
 * reference count will increase and the existing entry returns.
 *
 * When destroy an entry from list, decrease reference count and only
 * destroy when no further reference.
 *
 * Linked list is designed for limited number of entries,
 * read mostly, less modification.
 *
 * For huge amount of entries, please consider hash list.
 *
 */
struct mlx5_list {
	struct mlx5_list_const l_const;
	struct mlx5_list_inconst l_inconst;
};

/**
 * Create a mlx5 list.
 *
 * For actions in SW-steering is only memory and  can be allowed
 * to create duplicate objects, the lists don't need to check if
 * there are existing same objects in other sub local lists,
 * search the object only in local list will be more efficient.
 *
 * @param list
 *   Pointer to the hast list table.
 * @param name
 *   Name of the mlx5 list.
 * @param ctx
 *   Pointer to the list context data.
 * @param lcores_share
 *   Whether to share objects between the lcores.
 * @param cb_create
 *   Callback function for entry create.
 * @param cb_match
 *   Callback function for entry match.
 * @param cb_remove
 *   Callback function for entry remove.
 * @return
 *   List pointer on success, otherwise NULL.
 */
__rte_internal
struct mlx5_list *mlx5_list_create(const char *name, void *ctx,
				   bool lcores_share,
				   mlx5_list_create_cb cb_create,
				   mlx5_list_match_cb cb_match,
				   mlx5_list_remove_cb cb_remove,
				   mlx5_list_clone_cb cb_clone,
				   mlx5_list_clone_free_cb cb_clone_free);

/**
 * Search an entry matching the key.
 *
 * Result returned might be destroyed by other thread, must use
 * this function only in main thread.
 *
 * @param list
 *   Pointer to the mlx5 list.
 * @param ctx
 *   Common context parameter used by entry callback function.
 *
 * @return
 *   Pointer of the list entry if found, NULL otherwise.
 */
__rte_internal
struct mlx5_list_entry *mlx5_list_lookup(struct mlx5_list *list,
					   void *ctx);

/**
 * Reuse or create an entry to the mlx5 list.
 *
 * @param list
 *   Pointer to the hast list table.
 * @param ctx
 *   Common context parameter used by callback function.
 *
 * @return
 *   registered entry on success, NULL otherwise
 */
__rte_internal
struct mlx5_list_entry *mlx5_list_register(struct mlx5_list *list,
					     void *ctx);

/**
 * Remove an entry from the mlx5 list.
 *
 * User should guarantee the validity of the entry.
 *
 * @param list
 *   Pointer to the hast list.
 * @param entry
 *   Entry to be removed from the mlx5 list table.
 * @return
 *   0 on entry removed, 1 on entry still referenced.
 */
__rte_internal
int mlx5_list_unregister(struct mlx5_list *list,
			  struct mlx5_list_entry *entry);

/**
 * Destroy the mlx5 list.
 *
 * @param list
 *   Pointer to the mlx5 list.
 */
__rte_internal
void mlx5_list_destroy(struct mlx5_list *list);

/**
 * Get entry number from the mlx5 list.
 *
 * @param list
 *   Pointer to the hast list.
 * @return
 *   mlx5 list entry number.
 */
__rte_internal
uint32_t
mlx5_list_get_entry_num(struct mlx5_list *list);

/********************* Hash List **********************/

/* Hash list bucket. */
struct mlx5_hlist_bucket {
	struct mlx5_list_inconst l;
} __rte_cache_aligned;

/**
 * Hash list table structure
 *
 * The hash list bucket using the mlx5_list object for managing.
 */
struct mlx5_hlist {
	uint32_t mask; /* A mask for the bucket index range. */
	uint8_t flags;
	bool direct_key; /* Whether to use the key directly as hash index. */
	struct mlx5_list_const l_const; /* List constant data. */
	struct mlx5_hlist_bucket buckets[] __rte_cache_aligned;
};

/**
 * Create a hash list table, the user can specify the list heads array size
 * of the table, now the size should be a power of 2 in order to get better
 * distribution for the entries. Each entry is a part of the whole data element
 * and the caller should be responsible for the data element's allocation and
 * cleanup / free. Key of each entry will be calculated with CRC in order to
 * generate a little fairer distribution.
 *
 * @param name
 *   Name of the hash list(optional).
 * @param size
 *   Heads array size of the hash list.
 * @param entry_size
 *   Entry size to allocate if cb_create not specified.
 * @param direct key
 *   Whether to use the key directly as hash index.
 * @param lcores_share
 *   Whether to share objects between the lcores.
 * @param ctx
 *   The hlist instance context.
 * @param cb_create
 *   Callback function for entry create.
 * @param cb_match
 *   Callback function for entry match.
 * @param cb_remove
 *   Callback function for entry remove.
 * @param cb_clone
 *   Callback function for entry clone.
 * @param cb_clone_free
 *   Callback function for entry clone free.
 * @return
 *   Pointer of the hash list table created, NULL on failure.
 */
__rte_internal
struct mlx5_hlist *mlx5_hlist_create(const char *name, uint32_t size,
				     bool direct_key, bool lcores_share,
				     void *ctx, mlx5_list_create_cb cb_create,
				     mlx5_list_match_cb cb_match,
				     mlx5_list_remove_cb cb_remove,
				     mlx5_list_clone_cb cb_clone,
				     mlx5_list_clone_free_cb cb_clone_free);

/**
 * Search an entry matching the key.
 *
 * Result returned might be destroyed by other thread, must use
 * this function only in main thread.
 *
 * @param h
 *   Pointer to the hast list table.
 * @param key
 *   Key for the searching entry.
 * @param ctx
 *   Common context parameter used by entry callback function.
 *
 * @return
 *   Pointer of the hlist entry if found, NULL otherwise.
 */
__rte_internal
struct mlx5_list_entry *mlx5_hlist_lookup(struct mlx5_hlist *h, uint64_t key,
					   void *ctx);

/**
 * Insert an entry to the hash list table, the entry is only part of whole data
 * element and a 64B key is used for matching. User should construct the key or
 * give a calculated hash signature and guarantee there is no collision.
 *
 * @param h
 *   Pointer to the hast list table.
 * @param entry
 *   Entry to be inserted into the hash list table.
 * @param ctx
 *   Common context parameter used by callback function.
 *
 * @return
 *   registered entry on success, NULL otherwise
 */
__rte_internal
struct mlx5_list_entry *mlx5_hlist_register(struct mlx5_hlist *h, uint64_t key,
					     void *ctx);

/**
 * Remove an entry from the hash list table. User should guarantee the validity
 * of the entry.
 *
 * @param h
 *   Pointer to the hast list table. (not used)
 * @param entry
 *   Entry to be removed from the hash list table.
 * @return
 *   0 on entry removed, 1 on entry still referenced.
 */
__rte_internal
int mlx5_hlist_unregister(struct mlx5_hlist *h, struct mlx5_list_entry *entry);

/**
 * Destroy the hash list table, all the entries already inserted into the lists
 * will be handled by the callback function provided by the user (including
 * free if needed) before the table is freed.
 *
 * @param h
 *   Pointer to the hast list table.
 */
__rte_internal
void mlx5_hlist_destroy(struct mlx5_hlist *h);

#endif /* RTE_PMD_MLX5_COMMON_UTILS_H_ */