/*

   * Copyright (c) 2008-2009 Cisco Systems, Inc.  All rights reserved.
   * Copyright (c) 2007-2008 Intel Corporation.  All rights reserved.

   *
   * This program is free software; you can redistribute it and/or modify it
   * under the terms and conditions of the GNU General Public License,
   * version 2, as published by the Free Software Foundation.
   *
   * This program is distributed in the hope it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
   * more details.
   *
   * You should have received a copy of the GNU General Public License along with
   * this program; if not, write to the Free Software Foundation, Inc.,
   * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * Maintained at www.Open-FCoE.org
   */
  
  #ifndef _LIBFCOE_H
  #define _LIBFCOE_H

  #include <linux/etherdevice.h>
  #include <linux/if_ether.h>

  #include <linux/netdevice.h>
  #include <linux/skbuff.h>

  #include <linux/workqueue.h>

  #include <linux/random.h>

  #include <scsi/fc/fc_fcoe.h>
  #include <scsi/libfc.h>

  #define FCOE_MAX_CMD_LEN	16	/* Supported CDB length */

  /*

   * Max MTU for FCoE: 14 (FCoE header) + 24 (FC header) + 2112 (max FC payload)
   * + 4 (FC CRC) + 4 (FCoE trailer) =  2158 bytes
   */
  #define FCOE_MTU	2158
  
  /*

   * FIP tunable parameters.
   */
  #define FCOE_CTLR_START_DELAY	2000	/* mS after first adv. to choose FCF */
  #define FCOE_CTRL_SOL_TOV	2000	/* min. solicitation interval (mS) */
  #define FCOE_CTLR_FCF_LIMIT	20	/* max. number of FCF entries */

  #define FCOE_CTLR_VN2VN_LOGIN_LIMIT 3	/* max. VN2VN rport login retries */

  
  /**
   * enum fip_state - internal state of FCoE controller.
   * @FIP_ST_DISABLED: 	controller has been disabled or not yet enabled.
   * @FIP_ST_LINK_WAIT:	the physical link is down or unusable.
   * @FIP_ST_AUTO:	determining whether to use FIP or non-FIP mode.
   * @FIP_ST_NON_FIP:	non-FIP mode selected.
   * @FIP_ST_ENABLED:	FIP mode selected.

   * @FIP_ST_VNMP_START:	VN2VN multipath mode start, wait
   * @FIP_ST_VNMP_PROBE1:	VN2VN sent first probe, listening
   * @FIP_ST_VNMP_PROBE2:	VN2VN sent second probe, listening
   * @FIP_ST_VNMP_CLAIM:	VN2VN sent claim, waiting for responses
   * @FIP_ST_VNMP_UP:	VN2VN multipath mode operation

   */
  enum fip_state {
  	FIP_ST_DISABLED,
  	FIP_ST_LINK_WAIT,
  	FIP_ST_AUTO,
  	FIP_ST_NON_FIP,
  	FIP_ST_ENABLED,

  	FIP_ST_VNMP_START,
  	FIP_ST_VNMP_PROBE1,
  	FIP_ST_VNMP_PROBE2,
  	FIP_ST_VNMP_CLAIM,
  	FIP_ST_VNMP_UP,

  };

  /*
   * Modes:
   * The mode is the state that is to be entered after link up.
   * It must not change after fcoe_ctlr_init() sets it.
   */
  #define FIP_MODE_AUTO		FIP_ST_AUTO
  #define FIP_MODE_NON_FIP	FIP_ST_NON_FIP
  #define FIP_MODE_FABRIC		FIP_ST_ENABLED

  #define FIP_MODE_VN2VN		FIP_ST_VNMP_START

  /**

   * struct fcoe_ctlr - FCoE Controller and FIP state
   * @state:	   internal FIP state for network link and FIP or non-FIP mode.

   * @mode:	   LLD-selected mode.

   * @lp:		   &fc_lport: libfc local port.
   * @sel_fcf:	   currently selected FCF, or NULL.
   * @fcfs:	   list of discovered FCFs.
   * @fcf_count:	   number of discovered FCF entries.
   * @sol_time:	   time when a multicast solicitation was last sent.
   * @sel_time:	   time after which to select an FCF.
   * @port_ka_time:  time of next port keep-alive.
   * @ctlr_ka_time:  time of next controller keep-alive.
   * @timer:	   timer struct used for all delayed events.

   * @timer_work:	   &work_struct for doing keep-alives and resets.

   * @recv_work:	   &work_struct for receiving FIP frames.

   * @fip_recv_list: list of received FIP frames.

   * @flogi_req:	   clone of FLOGI request sent

   * @rnd_state:	   state for pseudo-random number generator.
   * @port_id:	   proposed or selected local-port ID.

   * @user_mfs:	   configured maximum FC frame size, including FC header.
   * @flogi_oxid:    exchange ID of most recent fabric login.

   * @flogi_req_send: send of FLOGI requested

   * @flogi_count:   number of FLOGI attempts in AUTO mode.

   * @map_dest:	   use the FC_MAP mode for destination MAC addresses.
   * @spma:	   supports SPMA server-provided MACs mode

   * @probe_tries:   number of FC_IDs probed

   * @dest_addr:	   MAC address of the selected FC forwarder.
   * @ctl_src_addr:  the native MAC address of our local port.
   * @send:	   LLD-supplied function to handle sending FIP Ethernet frames
   * @update_mac:    LLD-supplied function to handle changes to MAC addresses.
   * @get_src_addr:  LLD-supplied function to supply a source MAC address.

   * @ctlr_mutex:	   lock protecting this structure.

   * @ctlr_lock:     spinlock covering flogi_req

   *
   * This structure is used by all FCoE drivers.  It contains information
   * needed by all FCoE low-level drivers (LLDs) as well as internal state
   * for FIP, and fields shared with the LLDS.
   */
  struct fcoe_ctlr {
  	enum fip_state state;

  	enum fip_state mode;

  	struct fc_lport *lp;
  	struct fcoe_fcf *sel_fcf;
  	struct list_head fcfs;
  	u16 fcf_count;
  	unsigned long sol_time;
  	unsigned long sel_time;
  	unsigned long port_ka_time;
  	unsigned long ctlr_ka_time;
  	struct timer_list timer;

  	struct work_struct timer_work;

  	struct work_struct recv_work;
  	struct sk_buff_head fip_recv_list;

  	struct sk_buff *flogi_req;

  
  	struct rnd_state rnd_state;
  	u32 port_id;

  	u16 user_mfs;
  	u16 flogi_oxid;

  	u8 flogi_req_send;

  	u8 flogi_count;

  	u8 map_dest;

  	u8 spma;

  	u8 probe_tries;

  	u8 priority;

  	u8 dest_addr[ETH_ALEN];
  	u8 ctl_src_addr[ETH_ALEN];

  
  	void (*send)(struct fcoe_ctlr *, struct sk_buff *);

  	void (*update_mac)(struct fc_lport *, u8 *addr);
  	u8 * (*get_src_addr)(struct fc_lport *);

  	struct mutex ctlr_mutex;

  	spinlock_t ctlr_lock;

  };

  /**
   * struct fcoe_fcf - Fibre-Channel Forwarder
   * @list:	 list linkage
   * @time:	 system time (jiffies) when an advertisement was last received
   * @switch_name: WWN of switch from advertisement
   * @fabric_name: WWN of fabric from advertisement
   * @fc_map:	 FC_MAP value from advertisement
   * @fcf_mac:	 Ethernet address of the FCF
   * @vfid:	 virtual fabric ID
   * @pri:	 selection priority, smaller values are better

   * @flogi_sent:	 current FLOGI sent to this FCF

   * @flags:	 flags received from advertisement
   * @fka_period:	 keep-alive period, in jiffies

   *
   * A Fibre-Channel Forwarder (FCF) is the entity on the Ethernet that
   * passes FCoE frames on to an FC fabric.  This structure represents
   * one FCF from which advertisements have been received.
   *
   * When looking up an FCF, @switch_name, @fabric_name, @fc_map, @vfid, and
   * @fcf_mac together form the lookup key.
   */
  struct fcoe_fcf {
  	struct list_head list;
  	unsigned long time;
  
  	u64 switch_name;
  	u64 fabric_name;
  	u32 fc_map;
  	u16 vfid;
  	u8 fcf_mac[ETH_ALEN];
  
  	u8 pri;

  	u8 flogi_sent;

  	u16 flags;
  	u32 fka_period;

  	u8 fd_flags:1;

  };

  /**
   * struct fcoe_rport - VN2VN remote port
   * @time:	time of create or last beacon packet received from node
   * @fcoe_len:	max FCoE frame size, not including VLAN or Ethernet headers
   * @flags:	flags from probe or claim
   * @login_count: number of unsuccessful rport logins to this port
   * @enode_mac:	E_Node control MAC address
   * @vn_mac:	VN_Node assigned MAC address for data
   */
  struct fcoe_rport {
  	unsigned long time;
  	u16 fcoe_len;
  	u16 flags;
  	u8 login_count;
  	u8 enode_mac[ETH_ALEN];
  	u8 vn_mac[ETH_ALEN];
  };

  /* FIP API functions */

  void fcoe_ctlr_init(struct fcoe_ctlr *, enum fip_state);

  void fcoe_ctlr_destroy(struct fcoe_ctlr *);
  void fcoe_ctlr_link_up(struct fcoe_ctlr *);
  int fcoe_ctlr_link_down(struct fcoe_ctlr *);

  int fcoe_ctlr_els_send(struct fcoe_ctlr *, struct fc_lport *, struct sk_buff *);

  void fcoe_ctlr_recv(struct fcoe_ctlr *, struct sk_buff *);

  int fcoe_ctlr_recv_flogi(struct fcoe_ctlr *, struct fc_lport *,

  			 struct fc_frame *);

  /* libfcoe funcs */

  u64 fcoe_wwn_from_mac(unsigned char mac[], unsigned int, unsigned int);

  int fcoe_libfc_config(struct fc_lport *, struct fcoe_ctlr *,
  		      const struct libfc_function_template *, int init_fcp);

  u32 fcoe_fc_crc(struct fc_frame *fp);
  int fcoe_start_io(struct sk_buff *skb);

  int fcoe_get_wwn(struct net_device *netdev, u64 *wwn, int type);

  void __fcoe_get_lesb(struct fc_lport *lport, struct fc_els_lesb *fc_lesb,
  		     struct net_device *netdev);

  void fcoe_wwn_to_str(u64 wwn, char *buf, int len);
  int fcoe_validate_vport_create(struct fc_vport *vport);

  /**
   * is_fip_mode() - returns true if FIP mode selected.
   * @fip:	FCoE controller.
   */
  static inline bool is_fip_mode(struct fcoe_ctlr *fip)
  {
  	return fip->state == FIP_ST_ENABLED;
  }

  /* helper for FCoE SW HBA drivers, can include subven and subdev if needed. The
   * modpost would use pci_device_id table to auto-generate formatted module alias
   * into the corresponding .mod.c file, but there may or may not be a pci device
   * id table for FCoE drivers so we use the following helper for build the fcoe
   * driver module alias.
   */
  #define MODULE_ALIAS_FCOE_PCI(ven, dev) \
  	MODULE_ALIAS("fcoe-pci:"	\
  		"v" __stringify(ven)	\
  		"d" __stringify(dev) "sv*sd*bc*sc*i*")
  
  /* the name of the default FCoE transport driver fcoe.ko */
  #define FCOE_TRANSPORT_DEFAULT	"fcoe"
  
  /* struct fcoe_transport - The FCoE transport interface
   * @name:	a vendor specific name for their FCoE transport driver
   * @attached:	whether this transport is already attached
   * @list:	list linkage to all attached transports
   * @match:	handler to allow the transport driver to match up a given netdev
   * @create:	handler to sysfs entry of create for FCoE instances
   * @destroy:	handler to sysfs entry of destroy for FCoE instances
   * @enable:	handler to sysfs entry of enable for FCoE instances
   * @disable:	handler to sysfs entry of disable for FCoE instances
   */
  struct fcoe_transport {
  	char name[IFNAMSIZ];
  	bool attached;
  	struct list_head list;
  	bool (*match) (struct net_device *device);
  	int (*create) (struct net_device *device, enum fip_state fip_mode);
  	int (*destroy) (struct net_device *device);
  	int (*enable) (struct net_device *device);
  	int (*disable) (struct net_device *device);
  };
  
  /**

   * struct fcoe_percpu_s - The context for FCoE receive thread(s)
   * @thread:	    The thread context
   * @fcoe_rx_list:   The queue of pending packets to process
   * @page:	    The memory page for calculating frame trailer CRCs
   * @crc_eof_offset: The offset into the CRC page pointing to available
   *		    memory for a new trailer
   */
  struct fcoe_percpu_s {
  	struct task_struct *thread;
  	struct sk_buff_head fcoe_rx_list;
  	struct page *crc_eof_page;
  	int crc_eof_offset;
  };
  
  /**
   * struct fcoe_port - The FCoE private structure
   * @priv:		       The associated fcoe interface. The structure is
   *			       defined by the low level driver
   * @lport:		       The associated local port
   * @fcoe_pending_queue:	       The pending Rx queue of skbs
   * @fcoe_pending_queue_active: Indicates if the pending queue is active

   * @priority:		       Packet priority (DCB)

   * @max_queue_depth:	       Max queue depth of pending queue
   * @min_queue_depth:	       Min queue depth of pending queue
   * @timer:		       The queue timer
   * @destroy_work:	       Handle for work context
   *			       (to prevent RTNL deadlocks)
   * @data_srt_addr:	       Source address for data
   *
   * An instance of this structure is to be allocated along with the
   * Scsi_Host and libfc fc_lport structures.
   */
  struct fcoe_port {
  	void		      *priv;
  	struct fc_lport	      *lport;
  	struct sk_buff_head   fcoe_pending_queue;
  	u8		      fcoe_pending_queue_active;

  	u8		      priority;

  	u32		      max_queue_depth;
  	u32		      min_queue_depth;
  	struct timer_list     timer;
  	struct work_struct    destroy_work;
  	u8		      data_src_addr[ETH_ALEN];
  };
  void fcoe_clean_pending_queue(struct fc_lport *);
  void fcoe_check_wait_queue(struct fc_lport *lport, struct sk_buff *skb);
  void fcoe_queue_timer(ulong lport);
  int fcoe_get_paged_crc_eof(struct sk_buff *skb, int tlen,
  			   struct fcoe_percpu_s *fps);
  
  /**

   * struct netdev_list
   * A mapping from netdevice to fcoe_transport
   */
  struct fcoe_netdev_mapping {
  	struct list_head list;
  	struct net_device *netdev;
  	struct fcoe_transport *ft;
  };
  
  /* fcoe transports registration and deregistration */
  int fcoe_transport_attach(struct fcoe_transport *ft);
  int fcoe_transport_detach(struct fcoe_transport *ft);

  #endif /* _LIBFCOE_H */