text: /*
   * Copyright (c) 2014 Intel Corporation. All rights reserved.
   * Copyright (c) 2014 Chelsio, Inc. All rights reserved.
   *
   * This software is available to you under a choice of one of two
   * licenses.  You may choose to be licensed under the terms of the GNU
   * General Public License (GPL) Version 2, available from the file
   * COPYING in the main directory of this source tree, or the
   * OpenIB.org BSD license below:
   *
   *     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.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
   * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
   * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
   * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
   * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
   * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
   * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
   * SOFTWARE.
   */
  #ifndef _IWPM_UTIL_H
  #define _IWPM_UTIL_H
  
  #include <linux/module.h>
  #include <linux/io.h>
  #include <linux/in.h>
  #include <linux/in6.h>
  #include <linux/spinlock.h>
  #include <linux/kernel.h>
  #include <linux/netdevice.h>
  #include <linux/delay.h>
  #include <linux/workqueue.h>
  #include <linux/mutex.h>
  #include <linux/jhash.h>
  #include <linux/kref.h>
  #include <net/netlink.h>
  #include <linux/errno.h>
  #include <rdma/iw_portmap.h>
  #include <rdma/rdma_netlink.h>
  
  
  #define IWPM_NL_RETRANS		3
  #define IWPM_NL_TIMEOUT		(10*HZ)
  #define IWPM_MAPINFO_SKB_COUNT	20
  
  #define IWPM_PID_UNDEFINED     -1
  #define IWPM_PID_UNAVAILABLE   -2
  
  #define IWPM_REG_UNDEF          0x01
  #define IWPM_REG_VALID          0x02
  #define IWPM_REG_INCOMPL        0x04
  
  struct iwpm_nlmsg_request {
  	struct list_head    inprocess_list;
  	__u32               nlmsg_seq;
  	void                *req_buffer;
  	u8	            nl_client;
  	u8                  request_done;
  	u16                 err_code;
  	wait_queue_head_t   waitq;
  	struct kref         kref;
  };
  
  struct iwpm_mapping_info {
  	struct hlist_node hlist_node;
  	struct sockaddr_storage local_sockaddr;
  	struct sockaddr_storage mapped_sockaddr;
  	u8     nl_client;
  };
  
  struct iwpm_remote_info {
  	struct hlist_node hlist_node;
  	struct sockaddr_storage remote_sockaddr;
  	struct sockaddr_storage mapped_loc_sockaddr;
  	struct sockaddr_storage mapped_rem_sockaddr;
  	u8     nl_client;
  };
  
  struct iwpm_admin_data {
  	atomic_t refcount;
  	atomic_t nlmsg_seq;
  	int      client_list[RDMA_NL_NUM_CLIENTS];
  	u32      reg_list[RDMA_NL_NUM_CLIENTS];
  };
  
  /**
   * iwpm_get_nlmsg_request - Allocate and initialize netlink message request
   * @nlmsg_seq: Sequence number of the netlink message
   * @nl_client: The index of the netlink client
   * @gfp: Indicates how the memory for the request should be allocated
   *
   * Returns the newly allocated netlink request object if successful,
   * otherwise returns NULL
   */
  struct iwpm_nlmsg_request *iwpm_get_nlmsg_request(__u32 nlmsg_seq,
  						u8 nl_client, gfp_t gfp);
  
  /**
   * iwpm_free_nlmsg_request - Deallocate netlink message request
   * @kref: Holds reference of netlink message request
   */
  void iwpm_free_nlmsg_request(struct kref *kref);
  
  /**
   * iwpm_find_nlmsg_request - Find netlink message request in the request list
   * @echo_seq: Sequence number of the netlink request to find
   *
   * Returns the found netlink message request,
   * if not found, returns NULL
   */
  struct iwpm_nlmsg_request *iwpm_find_nlmsg_request(__u32 echo_seq);
  
  /**
   * iwpm_wait_complete_req - Block while servicing the netlink request
   * @nlmsg_request: Netlink message request to service
   *
   * Wakes up, after the request is completed or expired
   * Returns 0 if the request is complete without error
   */
  int iwpm_wait_complete_req(struct iwpm_nlmsg_request *nlmsg_request);
  
  /**
   * iwpm_get_nlmsg_seq - Get the sequence number for a netlink
   *			message to send to the port mapper
   *
   * Returns the sequence number for the netlink message.
   */
  int iwpm_get_nlmsg_seq(void);
  
  /**
   * iwpm_add_reminfo - Add remote address info of the connecting peer
   *                    to the remote info hash table
   * @reminfo: The remote info to be added
   */
  void iwpm_add_remote_info(struct iwpm_remote_info *reminfo);
  
  /**
   * iwpm_valid_client - Check if the port mapper client is valid
   * @nl_client: The index of the netlink client
   *
   * Valid clients need to call iwpm_init() before using
   * the port mapper
   */
  int iwpm_valid_client(u8 nl_client);
  
  /**
   * iwpm_set_valid - Set the port mapper client to valid or not
   * @nl_client: The index of the netlink client
   * @valid: 1 if valid or 0 if invalid
   */
  void iwpm_set_valid(u8 nl_client, int valid);
  
  /**
   * iwpm_check_registration - Check if the client registration
   *			      matches the given one
   * @nl_client: The index of the netlink client
   * @reg: The given registration type to compare with
   *
   * Call iwpm_register_pid() to register a client
   * Returns true if the client registration matches reg,
   * otherwise returns false
   */
  u32 iwpm_check_registration(u8 nl_client, u32 reg);
  
  /**
   * iwpm_set_registration - Set the client registration
   * @nl_client: The index of the netlink client
   * @reg: Registration type to set
   */
  void iwpm_set_registration(u8 nl_client, u32 reg);
  
  /**
   * iwpm_get_registration
   * @nl_client: The index of the netlink client
   *
   * Returns the client registration type
   */
  u32 iwpm_get_registration(u8 nl_client);
  
  /**
   * iwpm_send_mapinfo - Send local and mapped IPv4/IPv6 address info of
   *                     a client to the user space port mapper
   * @nl_client: The index of the netlink client
   * @iwpm_pid: The pid of the user space port mapper
   *
   * If successful, returns the number of sent mapping info records
   */
  int iwpm_send_mapinfo(u8 nl_client, int iwpm_pid);
  
  /**
   * iwpm_mapinfo_available - Check if any mapping info records is available
   *		            in the hash table
   *
   * Returns 1 if mapping information is available, otherwise returns 0
   */
  int iwpm_mapinfo_available(void);
  
  /**
   * iwpm_compare_sockaddr - Compare two sockaddr storage structs
   *
   * Returns 0 if they are holding the same ip/tcp address info,
   * otherwise returns 1
   */
  int iwpm_compare_sockaddr(struct sockaddr_storage *a_sockaddr,
  			struct sockaddr_storage *b_sockaddr);
  
  /**
   * iwpm_validate_nlmsg_attr - Check for NULL netlink attributes
   * @nltb: Holds address of each netlink message attributes
   * @nla_count: Number of netlink message attributes
   *
   * Returns error if any of the nla_count attributes is NULL
   */
  static inline int iwpm_validate_nlmsg_attr(struct nlattr *nltb[],
  					   int nla_count)
  {
  	int i;
  	for (i = 1; i < nla_count; i++) {
  		if (!nltb[i])
  			return -EINVAL;
  	}
  	return 0;
  }
  
  /**
   * iwpm_create_nlmsg - Allocate skb and form a netlink message
   * @nl_op: Netlink message opcode
   * @nlh: Holds address of the netlink message header in skb
   * @nl_client: The index of the netlink client
   *
   * Returns the newly allcated skb, or NULL if the tailroom of the skb
   * is insufficient to store the message header and payload
   */
  struct sk_buff *iwpm_create_nlmsg(u32 nl_op, struct nlmsghdr **nlh,
  					int nl_client);
  
  /**
   * iwpm_parse_nlmsg - Validate and parse the received netlink message
   * @cb: Netlink callback structure
   * @policy_max: Maximum attribute type to be expected
   * @nlmsg_policy: Validation policy
   * @nltb: Array to store policy_max parsed elements
   * @msg_type: Type of netlink message
   *
   * Returns 0 on success or a negative error code
   */
  int iwpm_parse_nlmsg(struct netlink_callback *cb, int policy_max,
  				const struct nla_policy *nlmsg_policy,
  				struct nlattr *nltb[], const char *msg_type);
  
  /**
   * iwpm_print_sockaddr - Print IPv4/IPv6 address and TCP port
   * @sockaddr: Socket address to print
   * @msg: Message to print
   */
  void iwpm_print_sockaddr(struct sockaddr_storage *sockaddr, char *msg);
  #endif
  