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+/*-
+ * BSD LICENSE
+ *
+ * Copyright(c) 2010-2012 Intel Corporation. All rights reserved.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ * * Neither the name of Intel Corporation nor the names of its
+ * contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * version: DPDK.L.1.2.3-3
+ */
+
+#ifndef _RTE_HASH_H_
+#define _RTE_HASH_H_
+
+/**
+ * @file
+ *
+ * RTE Hash Table
+ */
+
+#include <stdint.h>
+#include <sys/queue.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/** Maximum size of hash table that can be created. */
+#define RTE_HASH_ENTRIES_MAX (1 << 26)
+
+/** Maximum bucket size that can be created. */
+#define RTE_HASH_BUCKET_ENTRIES_MAX 16
+
+/** Maximum length of key that can be used. */
+#define RTE_HASH_KEY_LENGTH_MAX 64
+
+/** Max number of keys that can be searched for using rte_hash_lookup_multi. */
+#define RTE_HASH_LOOKUP_MULTI_MAX 16
+
+/** Max number of characters in hash name.*/
+#define RTE_HASH_NAMESIZE 32
+
+/** Signature of key that is stored internally. */
+typedef uint32_t hash_sig_t;
+
+/** Type of function that can be used for calculating the hash value. */
+typedef uint32_t (*rte_hash_function)(const void *key, uint32_t key_len,
+ uint32_t init_val);
+
+/**
+ * Parameters used when creating the hash table. The total table entries and
+ * bucket entries must be a power of 2.
+ */
+struct rte_hash_parameters {
+ const char *name; /**< Name of the hash. */
+ uint32_t entries; /**< Total hash table entries. */
+ uint32_t bucket_entries; /**< Bucket entries. */
+ uint32_t key_len; /**< Length of hash key. */
+ rte_hash_function hash_func; /**< Function used to calculate hash. */
+ uint32_t hash_func_init_val; /**< Init value used by hash_func. */
+ int socket_id; /**< NUMA Socket ID for memory. */
+};
+
+/** A hash table structure. */
+struct rte_hash {
+ TAILQ_ENTRY(rte_hash) next;/**< Next in list. */
+
+ char name[RTE_HASH_NAMESIZE]; /**< Name of the hash. */
+ uint32_t entries; /**< Total table entries. */
+ uint32_t bucket_entries; /**< Bucket entries. */
+ uint32_t key_len; /**< Length of hash key. */
+ rte_hash_function hash_func; /**< Function used to calculate hash. */
+ uint32_t hash_func_init_val; /**< Init value used by hash_func. */
+ uint32_t num_buckets; /**< Number of buckets in table. */
+ uint32_t bucket_bitmask; /**< Bitmask for getting bucket index
+ from hash signature. */
+ hash_sig_t sig_msb; /**< MSB is always set in valid signatures. */
+ uint8_t *sig_tbl; /**< Flat array of hash signature buckets. */
+ uint32_t sig_tbl_bucket_size; /**< Signature buckets may be padded for
+ alignment reasons, and this is the
+ bucket size used by sig_tbl. */
+ uint8_t *key_tbl; /**< Flat array of key value buckets. */
+ uint32_t key_tbl_key_size; /**< Keys may be padded for alignment
+ reasons, and this is the key size
+ used by key_tbl. */
+};
+
+/**
+ * Create a new hash table. If RTE_LIBRTE_HASH_USE_MEMZONE is defined, then
+ * the hash table is allocated in a memzone on a specific NUMA socket ID,
+ * otherwise it is allocated in the heap.
+ *
+ * @param params
+ * Parameters used to create and initialise the hash table.
+ * @return
+ * Pointer to hash table structure that is used in future hash table
+ * operations, or NULL on error, with error code set in rte_errno.
+ * Possible rte_errno errors include:
+ * - E_RTE_NO_CONFIG - function could not get pointer to rte_config structure
+ * - E_RTE_SECONDARY - function was called from a secondary process instance
+ * - E_RTE_NO_TAILQ - no tailq list could be got for the hash table list
+ * - ENOENT - missing entry
+ * - EINVAL - invalid parameter passed to function
+ * - ENOSPC - the maximum number of memzones has already been allocated
+ * - EEXIST - a memzone with the same name already exists
+ * - ENOMEM - no appropriate memory area found in which to create memzone
+ */
+struct rte_hash *
+rte_hash_create(const struct rte_hash_parameters *params);
+
+
+/**
+ * Find an existing hash table object and return a pointer to it.
+ *
+ * @param name
+ * Name of the hash table as passed to rte_hash_create()
+ * @return
+ * Pointer to hash table or NULL if object not found
+ * with rte_errno set appropriately. Possible rte_errno values include:
+ * - ENOENT - value not available for return
+ */
+struct rte_hash *
+rte_hash_find_existing(const char *name);
+
+/**
+ * De-allocate all memory used by hash table. If RTE_LIBRTE_HASH_USE_MEMZONE
+ * is defined, then this has no effect.
+ * @param h
+ * Hash table to free
+ */
+void
+rte_hash_free(struct rte_hash *h);
+
+/**
+ * Add a key to an existing hash table. This operation is not multi-thread safe
+ * and should only be called from one thread.
+ *
+ * @param h
+ * Hash table to add the key to.
+ * @param key
+ * Key to add to the hash table.
+ * @return
+ * - -EINVAL if the parameters are invalid.
+ * - -ENOSPC if there is no space in the hash for this key.
+ * - A positive value that can be used by the caller as an offset into an
+ * array of user data. This value is unique for this key.
+ */
+int32_t
+rte_hash_add_key(const struct rte_hash *h, const void *key);
+
+/**
+ * Remove a key from an existing hash table. This operation is not multi-thread
+ * safe and should only be called from one thread.
+ *
+ * @param h
+ * Hash table to remove the key from.
+ * @param key
+ * Key to remove from the hash table.
+ * @return
+ * - -EINVAL if the parameters are invalid.
+ * - -ENOENT if the key is not found.
+ * - A positive value that can be used by the caller as an offset into an
+ * array of user data. This value is unique for this key, and is the same
+ * value that was returned when the key was added.
+ */
+int32_t
+rte_hash_del_key(const struct rte_hash *h, const void *key);
+
+/**
+ * Find a key in the hash table. This operation is multi-thread safe.
+ *
+ * @param h
+ * Hash table to look in.
+ * @param key
+ * Key to find.
+ * @return
+ * - -EINVAL if the parameters are invalid.
+ * - -ENOENT if the key is not found.
+ * - A positive value that can be used by the caller as an offset into an
+ * array of user data. This value is unique for this key, and is the same
+ * value that was returned when the key was added.
+ */
+int32_t
+rte_hash_lookup(const struct rte_hash *h, const void *key);
+
+/**
+ * Find multiple keys in the hash table. This operation is multi-thread safe.
+ *
+ * @param h
+ * Hash table to look in.
+ * @param keys
+ * A pointer to a list of keys to look for.
+ * @param num_keys
+ * How many keys are in the keys list (less than RTE_HASH_LOOKUP_MULTI_MAX).
+ * @param positions
+ * Output containing a list of values, corresponding to the list of keys that
+ * can be used by the caller as an offset into an array of user data. These
+ * values are unique for each key, and are the same values that were returned
+ * when each key was added. If a key in the list was not found, then -ENOENT
+ * will be the value.
+ * @return
+ * -EINVAL if there's an error, otherwise 0.
+ */
+int
+rte_hash_lookup_multi(const struct rte_hash *h, const void **keys,
+ uint32_t num_keys, int32_t *positions);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _RTE_HASH_H_ */