/*
   * Copyright(c) 2007 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 _LIBFC_H_
  #define _LIBFC_H_
  
  #include <linux/timer.h>
  #include <linux/if.h>

  #include <linux/percpu.h>

  
  #include <scsi/scsi_transport.h>
  #include <scsi/scsi_transport_fc.h>

  #include <scsi/scsi_bsg_fc.h>

  
  #include <scsi/fc/fc_fcp.h>
  #include <scsi/fc/fc_ns.h>
  #include <scsi/fc/fc_els.h>
  #include <scsi/fc/fc_gs.h>
  
  #include <scsi/fc_frame.h>

  #define	FC_FC4_PROV_SIZE	(FC_TYPE_FCP + 1)	/* size of tables */

  /*
   * libfc error codes
   */
  #define	FC_NO_ERR	0	/* no error */
  #define	FC_EX_TIMEOUT	1	/* Exchange timeout */
  #define	FC_EX_CLOSED	2	/* Exchange closed */

  /**
   * enum fc_lport_state - Local port states
   * @LPORT_ST_DISABLED: Disabled
   * @LPORT_ST_FLOGI:    Fabric login (FLOGI) sent
   * @LPORT_ST_DNS:      Waiting for name server remote port to become ready
   * @LPORT_ST_RPN_ID:   Register port name by ID (RPN_ID) sent
   * @LPORT_ST_RFT_ID:   Register Fibre Channel types by ID (RFT_ID) sent

   * @LPORT_ST_RFF_ID:   Register FC-4 Features by ID (RFF_ID) sent

   * @LPORT_ST_SCR:      State Change Register (SCR) sent
   * @LPORT_ST_READY:    Ready for use
   * @LPORT_ST_LOGO:     Local port logout (LOGO) sent
   * @LPORT_ST_RESET:    Local port reset

   */

  enum fc_lport_state {

  	LPORT_ST_DISABLED = 0,

  	LPORT_ST_FLOGI,
  	LPORT_ST_DNS,

  	LPORT_ST_RNN_ID,

  	LPORT_ST_RSNN_NN,

  	LPORT_ST_RSPN_ID,

  	LPORT_ST_RFT_ID,

  	LPORT_ST_RFF_ID,

  	LPORT_ST_SCR,
  	LPORT_ST_READY,
  	LPORT_ST_LOGO,
  	LPORT_ST_RESET
  };
  
  enum fc_disc_event {
  	DISC_EV_NONE = 0,
  	DISC_EV_SUCCESS,
  	DISC_EV_FAILED
  };

  /**
   * enum fc_rport_state - Remote port states
   * @RPORT_ST_INIT:    Initialized

   * @RPORT_ST_FLOGI:   Waiting for FLOGI completion for point-to-multipoint
   * @RPORT_ST_PLOGI_WAIT:   Waiting for peer to login for point-to-multipoint

   * @RPORT_ST_PLOGI:   Waiting for PLOGI completion
   * @RPORT_ST_PRLI:    Waiting for PRLI completion
   * @RPORT_ST_RTV:     Waiting for RTV completion
   * @RPORT_ST_READY:   Ready for use

   * @RPORT_ST_ADISC:   Discover Address sent
   * @RPORT_ST_DELETE:  Remote port being deleted

  */

  enum fc_rport_state {

  	RPORT_ST_INIT,

  	RPORT_ST_FLOGI,
  	RPORT_ST_PLOGI_WAIT,

  	RPORT_ST_PLOGI,
  	RPORT_ST_PRLI,
  	RPORT_ST_RTV,
  	RPORT_ST_READY,

  	RPORT_ST_ADISC,
  	RPORT_ST_DELETE,

  };

  /**
   * struct fc_disc_port - temporary discovery port to hold rport identifiers

   * @lp:         Fibre Channel host port instance
   * @peers:      Node for list management during discovery and RSCN processing
   * @rport_work: Work struct for starting the rport state machine
   * @port_id:    Port ID of the discovered port

   */
  struct fc_disc_port {

  	struct fc_lport    *lp;
  	struct list_head   peers;
  	struct work_struct rport_work;
  	u32                port_id;

  };

  /**
   * enum fc_rport_event - Remote port events
   * @RPORT_EV_NONE:   No event
   * @RPORT_EV_READY:  Remote port is ready for use
   * @RPORT_EV_FAILED: State machine failed, remote port is not ready
   * @RPORT_EV_STOP:   Remote port has been stopped
   * @RPORT_EV_LOGO:   Remote port logout (LOGO) sent
   */

  enum fc_rport_event {
  	RPORT_EV_NONE = 0,

  	RPORT_EV_READY,

  	RPORT_EV_FAILED,
  	RPORT_EV_STOP,
  	RPORT_EV_LOGO
  };

  struct fc_rport_priv;

  /**
   * struct fc_rport_operations - Operations for a remote port
   * @event_callback: Function to be called for remote port events
   */

  struct fc_rport_operations {

  	void (*event_callback)(struct fc_lport *, struct fc_rport_priv *,

  			       enum fc_rport_event);
  };
  
  /**
   * struct fc_rport_libfc_priv - libfc internal information about a remote port

   * @local_port: The associated local port
   * @rp_state:   Indicates READY for I/O or DELETE when blocked
   * @flags:      REC and RETRY supported flags
   * @e_d_tov:    Error detect timeout value (in msec)
   * @r_a_tov:    Resource allocation timeout value (in msec)

   */
  struct fc_rport_libfc_priv {
  	struct fc_lport		   *local_port;
  	enum fc_rport_state        rp_state;
  	u16			   flags;
  	#define FC_RP_FLAGS_REC_SUPPORTED	(1 << 0)
  	#define FC_RP_FLAGS_RETRY		(1 << 1)

  	#define FC_RP_STARTED			(1 << 2)

  	#define FC_RP_FLAGS_CONF_REQ		(1 << 3)

  	unsigned int	           e_d_tov;
  	unsigned int	           r_a_tov;
  };
  
  /**

   * struct fc_rport_priv - libfc remote port and discovery info
   * @local_port:     The associated local port
   * @rport:          The FC transport remote port
   * @kref:           Reference counter
   * @rp_state:       Enumeration that tracks progress of PLOGI, PRLI,
   *                  and RTV exchanges
   * @ids:            The remote port identifiers and roles

   * @flags:          STARTED, REC and RETRY_SUPPORTED flags

   * @max_seq:        Maximum number of concurrent sequences
   * @disc_id:        The discovery identifier
   * @maxframe_size:  The maximum frame size
   * @retries:        The retry count for the current state

   * @major_retries:  The retry count for the entire PLOGI/PRLI state machine

   * @e_d_tov:        Error detect timeout value (in msec)
   * @r_a_tov:        Resource allocation timeout value (in msec)
   * @rp_mutex:       The mutex that protects the remote port
   * @retry_work:     Handle for retries
   * @event_callback: Callback when READY, FAILED or LOGO states complete

   * @prli_count:     Count of open PRLI sessions in providers

   * @rcu:	    Structure used for freeing in an RCU-safe manner

   */

  struct fc_rport_priv {

  	struct fc_lport		    *local_port;
  	struct fc_rport		    *rport;
  	struct kref		    kref;
  	enum fc_rport_state         rp_state;

  	struct fc_rport_identifiers ids;

  	u16			    flags;
  	u16		            max_seq;
  	u16			    disc_id;
  	u16			    maxframe_size;
  	unsigned int	            retries;

  	unsigned int	            major_retries;

  	unsigned int	            e_d_tov;
  	unsigned int	            r_a_tov;
  	struct mutex                rp_mutex;
  	struct delayed_work	    retry_work;
  	enum fc_rport_event         event;
  	struct fc_rport_operations  *ops;
  	struct list_head            peers;
  	struct work_struct          event_work;
  	u32			    supported_classes;

  	u16                         prli_count;

  	struct rcu_head		    rcu;

  	u16			    sp_features;
  	u8			    spp_type;
  	void			    (*lld_event_callback)(struct fc_lport *,
  						      struct fc_rport_priv *,
  						      enum fc_rport_event);

  };

  /**
   * struct fcoe_dev_stats - fcoe stats structure
   * @SecondsSinceLastReset: Seconds since the last reset
   * @TxFrames:              Number of transmitted frames
   * @TxWords:               Number of transmitted words
   * @RxFrames:              Number of received frames
   * @RxWords:               Number of received words
   * @ErrorFrames:           Number of received error frames
   * @DumpedFrames:          Number of dumped frames
   * @LinkFailureCount:      Number of link failures
   * @LossOfSignalCount:     Number for signal losses
   * @InvalidTxWordCount:    Number of invalid transmitted words
   * @InvalidCRCCount:       Number of invalid CRCs
   * @InputRequests:         Number of input requests
   * @OutputRequests:        Number of output requests
   * @ControlRequests:       Number of control requests

   * @InputBytes:            Number of received bytes
   * @OutputBytes:           Number of transmitted bytes

   * @VLinkFailureCount:     Number of virtual link failures
   * @MissDiscAdvCount:      Number of missing FIP discovery advertisement

   */
  struct fcoe_dev_stats {
  	u64		SecondsSinceLastReset;
  	u64		TxFrames;
  	u64		TxWords;
  	u64		RxFrames;
  	u64		RxWords;
  	u64		ErrorFrames;
  	u64		DumpedFrames;
  	u64		LinkFailureCount;
  	u64		LossOfSignalCount;
  	u64		InvalidTxWordCount;
  	u64		InvalidCRCCount;
  	u64		InputRequests;
  	u64		OutputRequests;
  	u64		ControlRequests;

  	u64		InputBytes;
  	u64		OutputBytes;

  	u64		VLinkFailureCount;
  	u64		MissDiscAdvCount;

  };

  /**
   * struct fc_seq_els_data - ELS data used for passing ELS specific responses

   * @reason: The reason for rejection

   * @explan: The explanation of the rejection

   *
   * Mainly used by the exchange manager layer.

   */
  struct fc_seq_els_data {

  	enum fc_els_rjt_reason reason;
  	enum fc_els_rjt_explan explan;
  };

  /**
   * struct fc_fcp_pkt - FCP request structure (one for each scsi_cmnd request)
   * @lp:              The associated local port
   * @state:           The state of the I/O

   * @ref_cnt:         Reference count
   * @scsi_pkt_lock:   Lock to protect the SCSI packet (must be taken before the
   *                   host_lock if both are to be held at the same time)
   * @cmd:             The SCSI command (set and clear with the host_lock held)
   * @list:            Tracks queued commands (accessed with the host_lock held)
   * @timer:           The command timer
   * @tm_done:         Completion indicator
   * @wait_for_comp:   Indicator to wait for completion of the I/O (in jiffies)

   * @data_len:        The length of the data
   * @cdb_cmd:         The CDB command
   * @xfer_len:        The transfer length
   * @xfer_ddp:        Indicates if this transfer used DDP (XID of the exchange
   *                   will be set here if DDP was setup)
   * @xfer_contig_end: The offset into the buffer if the buffer is contiguous
   *                   (Tx and Rx)
   * @max_payload:     The maximum payload size (in bytes)
   * @io_status:       SCSI result (upper 24 bits)
   * @cdb_status:      CDB status
   * @status_code:     FCP I/O status
   * @scsi_comp_flags: Completion flags (bit 3 Underrun bit 2: overrun)
   * @req_flags:       Request flags (bit 0: read bit:1 write)
   * @scsi_resid:      SCSI residule length
   * @rport:           The remote port that the SCSI command is targeted at
   * @seq_ptr:         The sequence that will carry the SCSI command
   * @recov_retry:     Number of recovery retries
   * @recov_seq:       The sequence for REC or SRR

   */
  struct fc_fcp_pkt {

  	spinlock_t	  scsi_pkt_lock;

  	atomic_t	  ref_cnt;
  
  	/* SCSI command and data transfer information */
  	u32		  data_len;

  
  	/* SCSI I/O related information */
  	struct scsi_cmnd  *cmd;
  	struct list_head  list;

  	/* Housekeeping information */
  	struct fc_lport   *lp;
  	u8		  state;

  
  	/* SCSI/FCP return status */

  	u8		  cdb_status;
  	u8		  status_code;
  	u8		  scsi_comp_flags;

  	u32		  io_status;

  	u32		  req_flags;
  	u32		  scsi_resid;

  	/* Transport related veriables */
  	size_t		  xfer_len;
  	struct fcp_cmnd   cdb_cmd;
  	u32		  xfer_contig_end;
  	u16		  max_payload;
  	u16		  xfer_ddp;

  	/* Associated structures */
  	struct fc_rport	  *rport;
  	struct fc_seq	  *seq_ptr;

  	/* Timeout/error related information */
  	struct timer_list timer;
  	int	          wait_for_comp;
  	u32		  recov_retry;

  	struct fc_seq	  *recov_seq;

  	struct completion tm_done;
  } ____cacheline_aligned_in_smp;

  
  /*
   * Structure and function definitions for managing Fibre Channel Exchanges
   * and Sequences
   *
   * fc_exch holds state for one exchange and links to its active sequence.
   *
   * fc_seq holds the state for an individual sequence.
   */
  
  struct fc_exch_mgr;

  struct fc_exch_mgr_anchor;

  extern u16 fc_cpu_mask;	/* cpu mask for possible cpus */

  /**
   * struct fc_seq - FC sequence
   * @id:       The sequence ID
   * @ssb_stat: Status flags for the sequence status block (SSB)
   * @cnt:      Number of frames sent so far
   * @rec_data: FC-4 value for REC

   */
  struct fc_seq {

  	u8  id;
  	u16 ssb_stat;
  	u16 cnt;
  	u32 rec_data;

  };
  
  #define FC_EX_DONE		(1 << 0) /* ep is completed */
  #define FC_EX_RST_CLEANUP	(1 << 1) /* reset is forcing completion */

  /**
   * struct fc_exch - Fibre Channel Exchange
   * @em:           Exchange manager
   * @pool:         Exchange pool
   * @state:        The exchange's state
   * @xid:          The exchange ID
   * @ex_list:      Handle used by the EM to track free exchanges
   * @ex_lock:      Lock that protects the exchange
   * @ex_refcnt:    Reference count
   * @timeout_work: Handle for timeout handler
   * @lp:           The local port that this exchange is on
   * @oxid:         Originator's exchange ID
   * @rxid:         Responder's exchange ID
   * @oid:          Originator's FCID
   * @sid:          Source FCID
   * @did:          Destination FCID
   * @esb_stat:     ESB exchange status
   * @r_a_tov:      Resouce allocation time out value (in msecs)
   * @seq_id:       The next sequence ID to use

   * @encaps:       encapsulation information for lower-level driver

   * @f_ctl:        F_CTL flags for the sequence
   * @fh_type:      The frame type
   * @class:        The class of service
   * @seq:          The sequence in use on this exchange
   * @resp:         Callback for responses on this exchange
   * @destructor:   Called when destroying the exchange
   * @arg:          Passed as a void pointer to the resp() callback

   *
   * Locking notes: The ex_lock protects following items:
   *	state, esb_stat, f_ctl, seq.ssb_stat
   *	seq_id
   *	sequence allocation
   */
  struct fc_exch {

  	spinlock_t	    ex_lock;
  	atomic_t	    ex_refcnt;
  	enum fc_class	    class;

  	struct fc_exch_mgr  *em;
  	struct fc_exch_pool *pool;

  	struct list_head    ex_list;

  	struct fc_lport	    *lp;

  	u32		    esb_stat;
  	u8		    state;
  	u8		    fh_type;
  	u8		    seq_id;
  	u8		    encaps;
  	u16		    xid;

  	u16		    oxid;
  	u16		    rxid;
  	u32		    oid;
  	u32		    sid;
  	u32		    did;

  	u32		    r_a_tov;

  	u32		    f_ctl;

  	struct fc_seq       seq;

  	void		    (*resp)(struct fc_seq *, struct fc_frame *, void *);
  	void		    *arg;

  	void		    (*destructor)(struct fc_seq *, void *);

  	struct delayed_work timeout_work;
  } ____cacheline_aligned_in_smp;

  #define	fc_seq_exch(sp) container_of(sp, struct fc_exch, seq)

  struct libfc_function_template {

  	/*
  	 * Interface to send a FC frame

  	 *

  	 * STATUS: REQUIRED

  	 */

  	int (*frame_send)(struct fc_lport *, struct fc_frame *);

  
  	/*

  	 * Interface to send ELS/CT frames
  	 *
  	 * STATUS: OPTIONAL

  	 */

  	struct fc_seq *(*elsct_send)(struct fc_lport *, u32 did,
  				     struct fc_frame *, unsigned int op,

  				     void (*resp)(struct fc_seq *,

  					     struct fc_frame *, void *arg),

  				     void *arg, u32 timer_msec);

  
  	/*
  	 * Send the FC frame payload using a new exchange and sequence.
  	 *

  	 * The exchange response handler is set in this routine to resp()
  	 * function pointer. It can be called in two scenarios: if a timeout
  	 * occurs or if a response frame is received for the exchange. The
  	 * fc_frame pointer in response handler will also indicate timeout
  	 * as error using IS_ERR related macros.
  	 *
  	 * The exchange destructor handler is also set in this routine.
  	 * The destructor handler is invoked by EM layer when exchange
  	 * is about to free, this can be used by caller to free its
  	 * resources along with exchange free.
  	 *
  	 * The arg is passed back to resp and destructor handler.
  	 *
  	 * The timeout value (in msec) for an exchange is set if non zero
  	 * timer_msec argument is specified. The timer is canceled when
  	 * it fires or when the exchange is done. The exchange timeout handler
  	 * is registered by EM layer.

  	 *
  	 * STATUS: OPTIONAL

  	 */

  	struct fc_seq *(*exch_seq_send)(struct fc_lport *, struct fc_frame *,
  					void (*resp)(struct fc_seq *,
  						     struct fc_frame *,
  						     void *),
  					void (*destructor)(struct fc_seq *,
  							   void *),
  					void *, unsigned int timer_msec);

  
  	/*

  	 * Sets up the DDP context for a given exchange id on the given
  	 * scatterlist if LLD supports DDP for large receive.
  	 *
  	 * STATUS: OPTIONAL
  	 */

  	int (*ddp_setup)(struct fc_lport *, u16, struct scatterlist *,
  			 unsigned int);

  	/*
  	 * Completes the DDP transfer and returns the length of data DDPed
  	 * for the given exchange id.
  	 *
  	 * STATUS: OPTIONAL
  	 */

  	int (*ddp_done)(struct fc_lport *, u16);

  	/*

  	 * Sets up the DDP context for a given exchange id on the given
  	 * scatterlist if LLD supports DDP for FCoE target.
  	 *
  	 * STATUS: OPTIONAL
  	 */
  	int (*ddp_target)(struct fc_lport *, u16, struct scatterlist *,
  			  unsigned int);
  	/*

  	 * Allow LLD to fill its own Link Error Status Block
  	 *
  	 * STATUS: OPTIONAL
  	 */
  	void (*get_lesb)(struct fc_lport *, struct fc_els_lesb *lesb);
  	/*

  	 * Send a frame using an existing sequence and exchange.
  	 *
  	 * STATUS: OPTIONAL

  	 */

  	int (*seq_send)(struct fc_lport *, struct fc_seq *,
  			struct fc_frame *);

  
  	/*

  	 * Send an ELS response using information from the received frame.

  	 *
  	 * STATUS: OPTIONAL

  	 */

  	void (*seq_els_rsp_send)(struct fc_frame *, enum fc_els_cmd,

  				 struct fc_seq_els_data *);

  
  	/*
  	 * Abort an exchange and sequence. Generally called because of a
  	 * exchange timeout or an abort from the upper layer.
  	 *
  	 * A timer_msec can be specified for abort timeout, if non-zero
  	 * timer_msec value is specified then exchange resp handler
  	 * will be called with timeout error if no response to abort.

  	 *
  	 * STATUS: OPTIONAL

  	 */

  	int (*seq_exch_abort)(const struct fc_seq *,

  			      unsigned int timer_msec);
  
  	/*
  	 * Indicate that an exchange/sequence tuple is complete and the memory
  	 * allocated for the related objects may be freed.

  	 *
  	 * STATUS: OPTIONAL

  	 */

  	void (*exch_done)(struct fc_seq *);

  
  	/*

  	 * Start a new sequence on the same exchange/sequence tuple.

  	 *
  	 * STATUS: OPTIONAL

  	 */

  	struct fc_seq *(*seq_start_next)(struct fc_seq *);

  
  	/*

  	 * Set a response handler for the exchange of the sequence.
  	 *
  	 * STATUS: OPTIONAL
  	 */
  	void (*seq_set_resp)(struct fc_seq *sp,
  			     void (*resp)(struct fc_seq *, struct fc_frame *,
  					  void *),
  			     void *arg);
  
  	/*

  	 * Assign a sequence for an incoming request frame.
  	 *
  	 * STATUS: OPTIONAL
  	 */
  	struct fc_seq *(*seq_assign)(struct fc_lport *, struct fc_frame *);
  
  	/*

  	 * Release the reference on the sequence returned by seq_assign().
  	 *
  	 * STATUS: OPTIONAL
  	 */
  	void (*seq_release)(struct fc_seq *);
  
  	/*

  	 * Reset an exchange manager, completing all sequences and exchanges.
  	 * If s_id is non-zero, reset only exchanges originating from that FID.
  	 * If d_id is non-zero, reset only exchanges sending to that FID.

  	 *
  	 * STATUS: OPTIONAL

  	 */

  	void (*exch_mgr_reset)(struct fc_lport *, u32 s_id, u32 d_id);

  	/*
  	 * Flush the rport work queue. Generally used before shutdown.
  	 *
  	 * STATUS: OPTIONAL

  	 */

  	void (*rport_flush_queue)(void);

  
  	/*

  	 * Receive a frame for a local port.
  	 *
  	 * STATUS: OPTIONAL

  	 */

  	void (*lport_recv)(struct fc_lport *, struct fc_frame *);

  	/*
  	 * Reset the local port.
  	 *
  	 * STATUS: OPTIONAL

  	 */

  	int (*lport_reset)(struct fc_lport *);

  
  	/*

  	 * Set the local port FC_ID.
  	 *
  	 * This may be provided by the LLD to allow it to be
  	 * notified when the local port is assigned a FC-ID.
  	 *
  	 * The frame, if non-NULL, is the incoming frame with the
  	 * FLOGI LS_ACC or FLOGI, and may contain the granted MAC
  	 * address for the LLD.  The frame pointer may be NULL if
  	 * no MAC is associated with this assignment (LOGO or PLOGI).
  	 *
  	 * If FC_ID is non-zero, r_a_tov and e_d_tov must be valid.
  	 *
  	 * Note: this is called with the local port mutex held.
  	 *
  	 * STATUS: OPTIONAL
  	 */
  	void (*lport_set_port_id)(struct fc_lport *, u32 port_id,
  				  struct fc_frame *);
  
  	/*

  	 * Create a remote port with a given port ID
  	 *
  	 * STATUS: OPTIONAL

  	 */

  	struct fc_rport_priv *(*rport_create)(struct fc_lport *, u32);

  
  	/*

  	 * Initiates the RP state machine. It is called from the LP module.
  	 * This function will issue the following commands to the N_Port
  	 * identified by the FC ID provided.
  	 *
  	 * - PLOGI
  	 * - PRLI
  	 * - RTV

  	 *
  	 * STATUS: OPTIONAL

  	 */

  	int (*rport_login)(struct fc_rport_priv *);

  
  	/*
  	 * Logoff, and remove the rport from the transport if
  	 * it had been added. This will send a LOGO to the target.

  	 *
  	 * STATUS: OPTIONAL

  	 */

  	int (*rport_logoff)(struct fc_rport_priv *);

  
  	/*

  	 * Receive a request from a remote port.

  	 *
  	 * STATUS: OPTIONAL

  	 */

  	void (*rport_recv_req)(struct fc_lport *, struct fc_frame *);

  	/*
  	 * lookup an rport by it's port ID.
  	 *
  	 * STATUS: OPTIONAL

  	 */

  	struct fc_rport_priv *(*rport_lookup)(const struct fc_lport *, u32);

  
  	/*

  	 * Destroy an rport after final kref_put().
  	 * The argument is a pointer to the kref inside the fc_rport_priv.
  	 */
  	void (*rport_destroy)(struct kref *);
  
  	/*

  	 * Callback routine after the remote port is logged in
  	 *
  	 * STATUS: OPTIONAL
  	 */
  	void (*rport_event_callback)(struct fc_lport *,
  				     struct fc_rport_priv *,
  				     enum fc_rport_event);
  
  	/*

  	 * Send a fcp cmd from fsp pkt.
  	 * Called with the SCSI host lock unlocked and irqs disabled.
  	 *
  	 * The resp handler is called when FCP_RSP received.
  	 *

  	 * STATUS: OPTIONAL

  	 */

  	int (*fcp_cmd_send)(struct fc_lport *, struct fc_fcp_pkt *,
  			    void (*resp)(struct fc_seq *, struct fc_frame *,
  					 void *));

  
  	/*

  	 * Cleanup the FCP layer, used during link down and reset

  	 *
  	 * STATUS: OPTIONAL

  	 */

  	void (*fcp_cleanup)(struct fc_lport *);

  
  	/*
  	 * Abort all I/O on a local port

  	 *
  	 * STATUS: OPTIONAL

  	 */

  	void (*fcp_abort_io)(struct fc_lport *);

  	/*
  	 * Receive a request for the discovery layer.
  	 *
  	 * STATUS: OPTIONAL

  	 */

  	void (*disc_recv_req)(struct fc_lport *, struct fc_frame *);

  
  	/*
  	 * Start discovery for a local port.

  	 *
  	 * STATUS: OPTIONAL

  	 */
  	void (*disc_start)(void (*disc_callback)(struct fc_lport *,
  						 enum fc_disc_event),
  			   struct fc_lport *);
  
  	/*
  	 * Stop discovery for a given lport. This will remove
  	 * all discovered rports

  	 *
  	 * STATUS: OPTIONAL

  	 */
  	void (*disc_stop) (struct fc_lport *);
  
  	/*
  	 * Stop discovery for a given lport. This will block
  	 * until all discovered rports are deleted from the
  	 * FC transport class

  	 *
  	 * STATUS: OPTIONAL

  	 */
  	void (*disc_stop_final) (struct fc_lport *);
  };

  /**
   * struct fc_disc - Discovery context
   * @retry_count:   Number of retries
   * @pending:       1 if discovery is pending, 0 if not

   * @requested:     1 if discovery has been requested, 0 if not

   * @seq_count:     Number of sequences used for discovery
   * @buf_len:       Length of the discovery buffer
   * @disc_id:       Discovery ID
   * @rports:        List of discovered remote ports

   * @priv:          Private pointer for use by discovery code

   * @disc_mutex:    Mutex that protects the discovery context
   * @partial_buf:   Partial name buffer (if names are returned
   *                 in multiple frames)
   * @disc_work:     handle for delayed work context
   * @disc_callback: Callback routine called when discovery completes
   */

  struct fc_disc {

  	unsigned char         retry_count;
  	unsigned char         pending;
  	unsigned char         requested;
  	unsigned short        seq_count;
  	unsigned char         buf_len;
  	u16                   disc_id;
  
  	struct list_head      rports;

  	void		      *priv;

  	struct mutex	      disc_mutex;
  	struct fc_gpn_ft_resp partial_buf;
  	struct delayed_work   disc_work;

  
  	void (*disc_callback)(struct fc_lport *,
  			      enum fc_disc_event);

  };

  /*
   * Local port notifier and events.
   */
  extern struct blocking_notifier_head fc_lport_notifier_head;
  enum fc_lport_event {
  	FC_LPORT_EV_ADD,
  	FC_LPORT_EV_DEL,
  };

  /**
   * struct fc_lport - Local port
   * @host:                  The SCSI host associated with a local port
   * @ema_list:              Exchange manager anchor list
   * @dns_rdata:             The directory server remote port
   * @ptp_rdata:             Point to point remote port
   * @scsi_priv:             FCP layer internal data
   * @disc:                  Discovery context
   * @vports:                Child vports if N_Port
   * @vport:                 Parent vport if VN_Port
   * @tt:                    Libfc function template
   * @link_up:               Link state (1 = link up, 0 = link down)
   * @qfull:                 Queue state (1 queue is full, 0 queue is not full)
   * @state:                 Identifies the state
   * @boot_time:             Timestamp indicating when the local port came online
   * @host_stats:            SCSI host statistics
   * @dev_stats:             FCoE device stats (TODO: libfc should not be
   *                         FCoE aware)
   * @retry_count:           Number of retries in the current state

   * @port_id:               FC Port ID

   * @wwpn:                  World Wide Port Name
   * @wwnn:                  World Wide Node Name
   * @service_params:        Common service parameters
   * @e_d_tov:               Error detection timeout value
   * @r_a_tov:               Resouce allocation timeout value
   * @rnid_gen:              RNID information
   * @sg_supp:               Indicates if scatter gather is supported
   * @seq_offload:           Indicates if sequence offload is supported
   * @crc_offload:           Indicates if CRC offload is supported
   * @lro_enabled:           Indicates if large receive offload is supported
   * @does_npiv:             Supports multiple vports
   * @npiv_enabled:          Switch/fabric allows NPIV
   * @mfs:                   The maximum Fibre Channel payload size
   * @max_retry_count:       The maximum retry attempts
   * @max_rport_retry_count: The maximum remote port retry attempts

   * @rport_priv_size:       Size needed by driver after struct fc_rport_priv

   * @lro_xid:               The maximum XID for LRO
   * @lso_max:               The maximum large offload send size
   * @fcts:                  FC-4 type mask
   * @lp_mutex:              Mutex to protect the local port

   * @list:                  Linkage on list of vport peers

   * @retry_work:            Handle to local port for delayed retry context

   * @prov:		   Pointers available for use by passive FC-4 providers

   * @lport_list:            Linkage on module-wide list of local ports

   */

  struct fc_lport {

  	/* Associations */

  	struct Scsi_Host	       *host;
  	struct list_head	       ema_list;
  	struct fc_rport_priv	       *dns_rdata;
  	struct fc_rport_priv	       *ptp_rdata;
  	void			       *scsi_priv;
  	struct fc_disc                 disc;
  
  	/* Virtual port information */
  	struct list_head	       vports;
  	struct fc_vport		       *vport;

  
  	/* Operational Information */
  	struct libfc_function_template tt;

  	u8			       link_up;
  	u8			       qfull;
  	enum fc_lport_state	       state;
  	unsigned long		       boot_time;
  	struct fc_host_statistics      host_stats;
  	struct fcoe_dev_stats	       *dev_stats;
  	u8			       retry_count;
  
  	/* Fabric information */

  	u32                            port_id;

  	u64			       wwpn;
  	u64			       wwnn;
  	unsigned int		       service_params;
  	unsigned int		       e_d_tov;
  	unsigned int		       r_a_tov;
  	struct fc_els_rnid_gen	       rnid_gen;

  
  	/* Capabilities */

  	u32			       sg_supp:1;
  	u32			       seq_offload:1;
  	u32			       crc_offload:1;
  	u32			       lro_enabled:1;
  	u32			       does_npiv:1;
  	u32			       npiv_enabled:1;

  	u32			       point_to_multipoint:1;

  	u32			       mfs;
  	u8			       max_retry_count;
  	u8			       max_rport_retry_count;

  	u16			       rport_priv_size;

  	u16			       link_speed;
  	u16			       link_supported_speeds;
  	u16			       lro_xid;
  	unsigned int		       lso_max;
  	struct fc_ns_fts	       fcts;

  
  	/* Miscellaneous */

  	struct mutex                   lp_mutex;
  	struct list_head               list;
  	struct delayed_work	       retry_work;

  	void			       *prov[FC_FC4_PROV_SIZE];

  	struct list_head               lport_list;

  };

  /**
   * struct fc4_prov - FC-4 provider registration
   * @prli:               Handler for incoming PRLI
   * @prlo:               Handler for session reset
   * @recv:		Handler for incoming request
   * @module:		Pointer to module.  May be NULL.
   */
  struct fc4_prov {
  	int (*prli)(struct fc_rport_priv *, u32 spp_len,
  		    const struct fc_els_spp *spp_in,
  		    struct fc_els_spp *spp_out);
  	void (*prlo)(struct fc_rport_priv *);
  	void (*recv)(struct fc_lport *, struct fc_frame *);
  	struct module *module;
  };
  
  /*
   * Register FC-4 provider with libfc.
   */
  int fc_fc4_register_provider(enum fc_fh_type type, struct fc4_prov *);
  void fc_fc4_deregister_provider(enum fc_fh_type type, struct fc4_prov *);

  /*

   * FC_LPORT HELPER FUNCTIONS
   *****************************/

  
  /**
   * fc_lport_test_ready() - Determine if a local port is in the READY state
   * @lport: The local port to test
   */
  static inline int fc_lport_test_ready(struct fc_lport *lport)

  {

  	return lport->state == LPORT_ST_READY;

  }

  /**
   * fc_set_wwnn() - Set the World Wide Node Name of a local port
   * @lport: The local port whose WWNN is to be set
   * @wwnn:  The new WWNN
   */
  static inline void fc_set_wwnn(struct fc_lport *lport, u64 wwnn)

  {

  	lport->wwnn = wwnn;

  }

  /**
   * fc_set_wwpn() - Set the World Wide Port Name of a local port
   * @lport: The local port whose WWPN is to be set
   * @wwnn:  The new WWPN
   */
  static inline void fc_set_wwpn(struct fc_lport *lport, u64 wwnn)

  {

  	lport->wwpn = wwnn;

  }

  /**
   * fc_lport_state_enter() - Change a local port's state
   * @lport: The local port whose state is to change
   * @state: The new state
   */
  static inline void fc_lport_state_enter(struct fc_lport *lport,

  					enum fc_lport_state state)
  {

  	if (state != lport->state)
  		lport->retry_count = 0;
  	lport->state = state;

  }

  /**
   * fc_lport_init_stats() - Allocate per-CPU statistics for a local port
   * @lport: The local port whose statistics are to be initialized
   */
  static inline int fc_lport_init_stats(struct fc_lport *lport)

  {

  	lport->dev_stats = alloc_percpu(struct fcoe_dev_stats);
  	if (!lport->dev_stats)

  		return -ENOMEM;
  	return 0;
  }

  /**
   * fc_lport_free_stats() - Free memory for a local port's statistics
   * @lport: The local port whose statistics are to be freed
   */
  static inline void fc_lport_free_stats(struct fc_lport *lport)

  {

  	free_percpu(lport->dev_stats);

  }

  /**
   * lport_priv() - Return the private data from a local port
   * @lport: The local port whose private data is to be retreived
   */
  static inline void *lport_priv(const struct fc_lport *lport)

  {

  	return (void *)(lport + 1);

  }
  
  /**

   * libfc_host_alloc() - Allocate a Scsi_Host with room for a local port and
   *                      LLD private data
   * @sht:       The SCSI host template
   * @priv_size: Size of private data

   *

   * Returns: libfc lport

   */

  static inline struct fc_lport *

  libfc_host_alloc(struct scsi_host_template *sht, int priv_size)
  {

  	struct fc_lport *lport;
  	struct Scsi_Host *shost;
  
  	shost = scsi_host_alloc(sht, sizeof(*lport) + priv_size);
  	if (!shost)
  		return NULL;
  	lport = shost_priv(shost);
  	lport->host = shost;
  	INIT_LIST_HEAD(&lport->ema_list);

  	INIT_LIST_HEAD(&lport->vports);

  	return lport;

  }

  /*

   * FC_FCP HELPER FUNCTIONS

   *****************************/

  static inline bool fc_fcp_is_read(const struct fc_fcp_pkt *fsp)
  {
  	if (fsp && fsp->cmd)
  		return fsp->cmd->sc_data_direction == DMA_FROM_DEVICE;
  	return false;
  }

  
  /*

   * LOCAL PORT LAYER
   *****************************/
  int fc_lport_init(struct fc_lport *);
  int fc_lport_destroy(struct fc_lport *);
  int fc_fabric_logoff(struct fc_lport *);
  int fc_fabric_login(struct fc_lport *);

  void __fc_linkup(struct fc_lport *);

  void fc_linkup(struct fc_lport *);

  void __fc_linkdown(struct fc_lport *);

  void fc_linkdown(struct fc_lport *);

  void fc_vport_setlink(struct fc_lport *);
  void fc_vports_linkchange(struct fc_lport *);

  int fc_lport_config(struct fc_lport *);

  int fc_lport_reset(struct fc_lport *);

  int fc_set_mfs(struct fc_lport *, u32 mfs);
  struct fc_lport *libfc_vport_create(struct fc_vport *, int privsize);
  struct fc_lport *fc_vport_id_lookup(struct fc_lport *, u32 port_id);
  int fc_lport_bsg_request(struct fc_bsg_job *);

  void fc_lport_set_local_id(struct fc_lport *, u32 port_id);

  void fc_lport_iterate(void (*func)(struct fc_lport *, void *), void *);

  
  /*

   * REMOTE PORT LAYER
   *****************************/

  int fc_rport_init(struct fc_lport *);
  void fc_rport_terminate_io(struct fc_rport *);

  /*

   * DISCOVERY LAYER
   *****************************/

  int fc_disc_init(struct fc_lport *);

  static inline struct fc_lport *fc_disc_lport(struct fc_disc *disc)
  {
  	return container_of(disc, struct fc_lport, disc);
  }

  /*

   * FCP LAYER

   *****************************/

  int fc_fcp_init(struct fc_lport *);

  void fc_fcp_destroy(struct fc_lport *);

  
  /*

   * SCSI INTERACTION LAYER
   *****************************/

  int fc_queuecommand(struct Scsi_Host *, struct scsi_cmnd *);

  int fc_eh_abort(struct scsi_cmnd *);
  int fc_eh_device_reset(struct scsi_cmnd *);
  int fc_eh_host_reset(struct scsi_cmnd *);
  int fc_slave_alloc(struct scsi_device *);
  int fc_change_queue_depth(struct scsi_device *, int qdepth, int reason);
  int fc_change_queue_type(struct scsi_device *, int tag_type);

  /*

   * ELS/CT interface
   *****************************/

  int fc_elsct_init(struct fc_lport *);
  struct fc_seq *fc_elsct_send(struct fc_lport *, u32 did,
  				    struct fc_frame *,

  				    unsigned int op,
  				    void (*resp)(struct fc_seq *,

  						 struct fc_frame *,

  						 void *arg),
  				    void *arg, u32 timer_msec);
  void fc_lport_flogi_resp(struct fc_seq *, struct fc_frame *, void *);
  void fc_lport_logo_resp(struct fc_seq *, struct fc_frame *, void *);

  void fc_fill_reply_hdr(struct fc_frame *, const struct fc_frame *,
  		       enum fc_rctl, u32 parm_offset);
  void fc_fill_hdr(struct fc_frame *, const struct fc_frame *,
  		 enum fc_rctl, u32 f_ctl, u16 seq_cnt, u32 parm_offset);

  /*

   * EXCHANGE MANAGER LAYER
   *****************************/

  int fc_exch_init(struct fc_lport *);
  struct fc_exch_mgr_anchor *fc_exch_mgr_add(struct fc_lport *,
  					   struct fc_exch_mgr *,

  					   bool (*match)(struct fc_frame *));

  void fc_exch_mgr_del(struct fc_exch_mgr_anchor *);

  int fc_exch_mgr_list_clone(struct fc_lport *src, struct fc_lport *dst);

  struct fc_exch_mgr *fc_exch_mgr_alloc(struct fc_lport *, enum fc_class class,
  				      u16 min_xid, u16 max_xid,

  				      bool (*match)(struct fc_frame *));

  void fc_exch_mgr_free(struct fc_lport *);
  void fc_exch_recv(struct fc_lport *, struct fc_frame *);

  void fc_exch_mgr_reset(struct fc_lport *, u32 s_id, u32 d_id);

  
  /*
   * Functions for fc_functions_template
   */

  void fc_get_host_speed(struct Scsi_Host *);

  void fc_get_host_port_state(struct Scsi_Host *);
  void fc_set_rport_loss_tmo(struct fc_rport *, u32 timeout);

  struct fc_host_statistics *fc_get_host_stats(struct Scsi_Host *);

  #endif /* _LIBFC_H_ */