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#ifndef __INCLUDE_RTE_TABLE_H__
#define __INCLUDE_RTE_TABLE_H__

#ifdef __cplusplus
extern "C" {
#endif

/**
 * @file
 * RTE Table
 *
 * This tool is part of the Intel DPDK Packet Framework tool suite and provides
 * a standard interface to implement different types of lookup tables for data
 * plane processing.
 *
 * Virtually any search algorithm that can uniquely associate data to a lookup
 * key can be fitted under this lookup table abstraction. For the flow table
 * use-case, the lookup key is an n-tuple of packet fields that uniquely
 * identifies a traffic flow, while data represents actions and action
 * meta-data associated with the same traffic flow.
 *
 ***/

#include <stdint.h>
#include <rte_mbuf.h>
#include <rte_port.h>

/**
 * Lookup table create
 *
 * @param params
 *   Parameters for lookup table creation. The underlying data structure is
 *   different for each lookup table type.
 * @param socket_id
 *   CPU socket ID (e.g. for memory allocation purpose)
 * @param entry_size
 *   Data size of each lookup table entry (measured in bytes)
 * @return
 *   Handle to lookup table instance
 */
typedef void* (*rte_table_op_create)(void *params, int socket_id,
	uint32_t entry_size);

/**
 * Lookup table free
 *
 * @param table
 *   Handle to lookup table instance
 * @return
 *   0 on success, error code otherwise
 */
typedef int (*rte_table_op_free)(void *table);

/**
 * Lookup table entry add
 *
 * @param table
 *   Handle to lookup table instance
 * @param key
 *   Lookup key
 * @param entry
 *   Data to be associated with the current key. This parameter has to point to
 *   a valid memory buffer where the first entry_size bytes (table create
 *   parameter) are populated with the data.
 * @param key_found
 *   After successful invocation, *key_found is set to a value different than 0
 *   if the current key is already present in the table and to 0 if not. This
 *   pointer has to be set to a valid memory location before the table entry add
 *   function is called.
 * @param entry_ptr
 *   After successful invocation, *entry_ptr stores the handle to the table
 *   entry containing the data associated with the current key. This handle can
 *   be used to perform further read-write accesses to this entry. This handle
 *   is valid until the key is deleted from the table or the same key is
 *   re-added to the table, typically to associate it with different data. This
 *   pointer has to be set to a valid memory location before the function is
 *   called.
 * @return
 *   0 on success, error code otherwise
 */
typedef int (*rte_table_op_entry_add)(
	void *table,
	void *key,
	void *entry,
	int *key_found,
	void **entry_ptr);

/**
 * Lookup table entry delete
 *
 * @param table
 *   Handle to lookup table instance
 * @param key
 *   Lookup key
 * @param key_found
 *   After successful invocation, *key_found is set to a value different than 0
 *   if the current key was present in the table before the delete operation
 *   was performed and to 0 if not. This pointer has to be set to a valid
 *   memory location before the table entry delete function is called.
 * @param entry
 *   After successful invocation, if the key is found in the table (*key found
 *   is different than 0 after function call is completed) and entry points to
 *   a valid buffer (entry is set to a value different than NULL before the
 *   function is called), then the first entry_size bytes (table create
 *   parameter) in *entry store a copy of table entry that contained the data
 *   associated with the current key before the key was deleted.
 * @return
 *   0 on success, error code otherwise
 */
typedef int (*rte_table_op_entry_delete)(
	void *table,
	void *key,
	int *key_found,
	void *entry);

/**
 * Lookup table lookup
 *
 * @param table
 *   Handle to lookup table instance
 * @param pkts
 *   Burst of input packets specified as array of up to 64 pointers to struct
 *   rte_mbuf
 * @param pkts_mask
 *   64-bit bitmask specifying which packets in the input burst are valid. When
 *   pkts_mask bit n is set, then element n of pkts array is pointing to a
 *   valid packet. Otherwise, element n of pkts array does not point to a valid
 *   packet, therefore it will not be accessed.
 * @param lookup_hit_mask
 *   Once the table lookup operation is completed, this 64-bit bitmask
 *   specifies which of the valid packets in the input burst resulted in lookup
 *   hit. For each valid input packet (pkts_mask bit n is set), the following
 *   are true on lookup hit: lookup_hit_mask bit n is set, element n of entries
 *   array is valid and it points to the lookup table entry that was hit. For
 *   each valid input packet (pkts_mask bit n is set), the following are true
 *   on lookup miss: lookup_hit_mask bit n is not set and element n of entries
 *   array is not valid.
 * @param entries
 *   Once the table lookup operation is completed, this array provides the
 *   lookup table entries that were hit, as described above. It is required
 *   that this array is always pre-allocated by the caller of this function
 *   with exactly 64 elements. The implementation is allowed to speculatively
 *   modify the elements of this array, so elements marked as invalid in
 *   lookup_hit_mask once the table lookup operation is completed might have
 *   been modified by this function.
 * @return
 *   0 on success, error code otherwise
 */
typedef int (*rte_table_op_lookup)(
	void *table,
	struct rte_mbuf **pkts,
	uint64_t pkts_mask,
	uint64_t *lookup_hit_mask,
	void **entries);

/** Lookup table interface defining the lookup table operation */
struct rte_table_ops {
	rte_table_op_create f_create;       /**< Create */
	rte_table_op_free f_free;           /**< Free */
	rte_table_op_entry_add f_add;       /**< Entry add */
	rte_table_op_entry_delete f_delete; /**< Entry delete */
	rte_table_op_lookup f_lookup;       /**< Lookup */
};

#ifdef __cplusplus
}
#endif

#endif
