xref: /linux/include/scsi/libfc.h (revision a5c4300389bb33ade2515c082709217f0614cf15)
1 /*
2  * Copyright(c) 2007 Intel Corporation. All rights reserved.
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms and conditions of the GNU General Public License,
6  * version 2, as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope it will be useful, but WITHOUT
9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
11  * more details.
12  *
13  * You should have received a copy of the GNU General Public License along with
14  * this program; if not, write to the Free Software Foundation, Inc.,
15  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
16  *
17  * Maintained at www.Open-FCoE.org
18  */
19 
20 #ifndef _LIBFC_H_
21 #define _LIBFC_H_
22 
23 #include <linux/timer.h>
24 #include <linux/if.h>
25 #include <linux/percpu.h>
26 
27 #include <scsi/scsi_transport.h>
28 #include <scsi/scsi_transport_fc.h>
29 #include <scsi/scsi_bsg_fc.h>
30 
31 #include <scsi/fc/fc_fcp.h>
32 #include <scsi/fc/fc_ns.h>
33 #include <scsi/fc/fc_els.h>
34 #include <scsi/fc/fc_gs.h>
35 
36 #include <scsi/fc_frame.h>
37 
38 /*
39  * libfc error codes
40  */
41 #define	FC_NO_ERR	0	/* no error */
42 #define	FC_EX_TIMEOUT	1	/* Exchange timeout */
43 #define	FC_EX_CLOSED	2	/* Exchange closed */
44 
45 /* some helpful macros */
46 
47 #define ntohll(x) be64_to_cpu(x)
48 #define htonll(x) cpu_to_be64(x)
49 
50 
51 static inline u32 ntoh24(const u8 *p)
52 {
53 	return (p[0] << 16) | (p[1] << 8) | p[2];
54 }
55 
56 static inline void hton24(u8 *p, u32 v)
57 {
58 	p[0] = (v >> 16) & 0xff;
59 	p[1] = (v >> 8) & 0xff;
60 	p[2] = v & 0xff;
61 }
62 
63 /**
64  * enum fc_lport_state - Local port states
65  * @LPORT_ST_DISABLED: Disabled
66  * @LPORT_ST_FLOGI:    Fabric login (FLOGI) sent
67  * @LPORT_ST_DNS:      Waiting for name server remote port to become ready
68  * @LPORT_ST_RPN_ID:   Register port name by ID (RPN_ID) sent
69  * @LPORT_ST_RFT_ID:   Register Fibre Channel types by ID (RFT_ID) sent
70  * @LPORT_ST_RFF_ID:   Register FC-4 Features by ID (RFF_ID) sent
71  * @LPORT_ST_SCR:      State Change Register (SCR) sent
72  * @LPORT_ST_READY:    Ready for use
73  * @LPORT_ST_LOGO:     Local port logout (LOGO) sent
74  * @LPORT_ST_RESET:    Local port reset
75  */
76 enum fc_lport_state {
77 	LPORT_ST_DISABLED = 0,
78 	LPORT_ST_FLOGI,
79 	LPORT_ST_DNS,
80 	LPORT_ST_RNN_ID,
81 	LPORT_ST_RSNN_NN,
82 	LPORT_ST_RSPN_ID,
83 	LPORT_ST_RFT_ID,
84 	LPORT_ST_RFF_ID,
85 	LPORT_ST_SCR,
86 	LPORT_ST_READY,
87 	LPORT_ST_LOGO,
88 	LPORT_ST_RESET
89 };
90 
91 enum fc_disc_event {
92 	DISC_EV_NONE = 0,
93 	DISC_EV_SUCCESS,
94 	DISC_EV_FAILED
95 };
96 
97 /**
98  * enum fc_rport_state - Remote port states
99  * @RPORT_ST_INIT:    Initialized
100  * @RPORT_ST_PLOGI:   Waiting for PLOGI completion
101  * @RPORT_ST_PRLI:    Waiting for PRLI completion
102  * @RPORT_ST_RTV:     Waiting for RTV completion
103  * @RPORT_ST_READY:   Ready for use
104  * @RPORT_ST_LOGO:    Remote port logout (LOGO) sent
105  * @RPORT_ST_ADISC:   Discover Address sent
106  * @RPORT_ST_DELETE:  Remote port being deleted
107  * @RPORT_ST_RESTART: Remote port being deleted and will restart
108 */
109 enum fc_rport_state {
110 	RPORT_ST_INIT,
111 	RPORT_ST_PLOGI,
112 	RPORT_ST_PRLI,
113 	RPORT_ST_RTV,
114 	RPORT_ST_READY,
115 	RPORT_ST_LOGO,
116 	RPORT_ST_ADISC,
117 	RPORT_ST_DELETE,
118 	RPORT_ST_RESTART,
119 };
120 
121 /**
122  * struct fc_disc_port - temporary discovery port to hold rport identifiers
123  * @lp:         Fibre Channel host port instance
124  * @peers:      Node for list management during discovery and RSCN processing
125  * @rport_work: Work struct for starting the rport state machine
126  * @port_id:    Port ID of the discovered port
127  */
128 struct fc_disc_port {
129 	struct fc_lport    *lp;
130 	struct list_head   peers;
131 	struct work_struct rport_work;
132 	u32                port_id;
133 };
134 
135 /**
136  * enum fc_rport_event - Remote port events
137  * @RPORT_EV_NONE:   No event
138  * @RPORT_EV_READY:  Remote port is ready for use
139  * @RPORT_EV_FAILED: State machine failed, remote port is not ready
140  * @RPORT_EV_STOP:   Remote port has been stopped
141  * @RPORT_EV_LOGO:   Remote port logout (LOGO) sent
142  */
143 enum fc_rport_event {
144 	RPORT_EV_NONE = 0,
145 	RPORT_EV_READY,
146 	RPORT_EV_FAILED,
147 	RPORT_EV_STOP,
148 	RPORT_EV_LOGO
149 };
150 
151 struct fc_rport_priv;
152 
153 /**
154  * struct fc_rport_operations - Operations for a remote port
155  * @event_callback: Function to be called for remote port events
156  */
157 struct fc_rport_operations {
158 	void (*event_callback)(struct fc_lport *, struct fc_rport_priv *,
159 			       enum fc_rport_event);
160 };
161 
162 /**
163  * struct fc_rport_libfc_priv - libfc internal information about a remote port
164  * @local_port: The associated local port
165  * @rp_state:   Indicates READY for I/O or DELETE when blocked
166  * @flags:      REC and RETRY supported flags
167  * @e_d_tov:    Error detect timeout value (in msec)
168  * @r_a_tov:    Resource allocation timeout value (in msec)
169  */
170 struct fc_rport_libfc_priv {
171 	struct fc_lport		   *local_port;
172 	enum fc_rport_state        rp_state;
173 	u16			   flags;
174 	#define FC_RP_FLAGS_REC_SUPPORTED	(1 << 0)
175 	#define FC_RP_FLAGS_RETRY		(1 << 1)
176 	unsigned int	           e_d_tov;
177 	unsigned int	           r_a_tov;
178 };
179 
180 /**
181  * struct fc_rport_priv - libfc remote port and discovery info
182  * @local_port:     The associated local port
183  * @rport:          The FC transport remote port
184  * @kref:           Reference counter
185  * @rp_state:       Enumeration that tracks progress of PLOGI, PRLI,
186  *                  and RTV exchanges
187  * @ids:            The remote port identifiers and roles
188  * @flags:          REC and RETRY supported flags
189  * @max_seq:        Maximum number of concurrent sequences
190  * @disc_id:        The discovery identifier
191  * @maxframe_size:  The maximum frame size
192  * @retries:        The retry count for the current state
193  * @e_d_tov:        Error detect timeout value (in msec)
194  * @r_a_tov:        Resource allocation timeout value (in msec)
195  * @rp_mutex:       The mutex that protects the remote port
196  * @retry_work:     Handle for retries
197  * @event_callback: Callback when READY, FAILED or LOGO states complete
198  */
199 struct fc_rport_priv {
200 	struct fc_lport		    *local_port;
201 	struct fc_rport		    *rport;
202 	struct kref		    kref;
203 	enum fc_rport_state         rp_state;
204 	struct fc_rport_identifiers ids;
205 	u16			    flags;
206 	u16		            max_seq;
207 	u16			    disc_id;
208 	u16			    maxframe_size;
209 	unsigned int	            retries;
210 	unsigned int	            e_d_tov;
211 	unsigned int	            r_a_tov;
212 	struct mutex                rp_mutex;
213 	struct delayed_work	    retry_work;
214 	enum fc_rport_event         event;
215 	struct fc_rport_operations  *ops;
216 	struct list_head            peers;
217 	struct work_struct          event_work;
218 	u32			    supported_classes;
219 };
220 
221 /**
222  * struct fcoe_dev_stats - fcoe stats structure
223  * @SecondsSinceLastReset: Seconds since the last reset
224  * @TxFrames:              Number of transmitted frames
225  * @TxWords:               Number of transmitted words
226  * @RxFrames:              Number of received frames
227  * @RxWords:               Number of received words
228  * @ErrorFrames:           Number of received error frames
229  * @DumpedFrames:          Number of dumped frames
230  * @LinkFailureCount:      Number of link failures
231  * @LossOfSignalCount:     Number for signal losses
232  * @InvalidTxWordCount:    Number of invalid transmitted words
233  * @InvalidCRCCount:       Number of invalid CRCs
234  * @InputRequests:         Number of input requests
235  * @OutputRequests:        Number of output requests
236  * @ControlRequests:       Number of control requests
237  * @InputMegabytes:        Number of received megabytes
238  * @OutputMegabytes:       Number of transmitted megabytes
239  * @VLinkFailureCount:     Number of virtual link failures
240  * @MissDiscAdvCount:      Number of missing FIP discovery advertisement
241  */
242 struct fcoe_dev_stats {
243 	u64		SecondsSinceLastReset;
244 	u64		TxFrames;
245 	u64		TxWords;
246 	u64		RxFrames;
247 	u64		RxWords;
248 	u64		ErrorFrames;
249 	u64		DumpedFrames;
250 	u64		LinkFailureCount;
251 	u64		LossOfSignalCount;
252 	u64		InvalidTxWordCount;
253 	u64		InvalidCRCCount;
254 	u64		InputRequests;
255 	u64		OutputRequests;
256 	u64		ControlRequests;
257 	u64		InputMegabytes;
258 	u64		OutputMegabytes;
259 	u64		VLinkFailureCount;
260 	u64		MissDiscAdvCount;
261 };
262 
263 /**
264  * struct fc_seq_els_data - ELS data used for passing ELS specific responses
265  * @fp:     The ELS frame
266  * @reason: The reason for rejection
267  * @explan: The explaination of the rejection
268  *
269  * Mainly used by the exchange manager layer.
270  */
271 struct fc_seq_els_data {
272 	struct fc_frame *fp;
273 	enum fc_els_rjt_reason reason;
274 	enum fc_els_rjt_explan explan;
275 };
276 
277 /**
278  * struct fc_fcp_pkt - FCP request structure (one for each scsi_cmnd request)
279  * @lp:              The associated local port
280  * @state:           The state of the I/O
281  * @tgt_flags:       Target's flags
282  * @ref_cnt:         Reference count
283  * @scsi_pkt_lock:   Lock to protect the SCSI packet (must be taken before the
284  *                   host_lock if both are to be held at the same time)
285  * @cmd:             The SCSI command (set and clear with the host_lock held)
286  * @list:            Tracks queued commands (accessed with the host_lock held)
287  * @timer:           The command timer
288  * @tm_done:         Completion indicator
289  * @wait_for_comp:   Indicator to wait for completion of the I/O (in jiffies)
290  * @start_time:      Timestamp indicating the start of the I/O (in jiffies)
291  * @end_time:        Timestamp indicating the end of the I/O (in jiffies)
292  * @last_pkt_time:   Timestamp of the last frame received (in jiffies)
293  * @data_len:        The length of the data
294  * @cdb_cmd:         The CDB command
295  * @xfer_len:        The transfer length
296  * @xfer_ddp:        Indicates if this transfer used DDP (XID of the exchange
297  *                   will be set here if DDP was setup)
298  * @xfer_contig_end: The offset into the buffer if the buffer is contiguous
299  *                   (Tx and Rx)
300  * @max_payload:     The maximum payload size (in bytes)
301  * @io_status:       SCSI result (upper 24 bits)
302  * @cdb_status:      CDB status
303  * @status_code:     FCP I/O status
304  * @scsi_comp_flags: Completion flags (bit 3 Underrun bit 2: overrun)
305  * @req_flags:       Request flags (bit 0: read bit:1 write)
306  * @scsi_resid:      SCSI residule length
307  * @rport:           The remote port that the SCSI command is targeted at
308  * @seq_ptr:         The sequence that will carry the SCSI command
309  * @recov_retry:     Number of recovery retries
310  * @recov_seq:       The sequence for REC or SRR
311  */
312 struct fc_fcp_pkt {
313 	/* Housekeeping information */
314 	struct fc_lport   *lp;
315 	u16		  state;
316 	u16		  tgt_flags;
317 	atomic_t	  ref_cnt;
318 	spinlock_t	  scsi_pkt_lock;
319 
320 	/* SCSI I/O related information */
321 	struct scsi_cmnd  *cmd;
322 	struct list_head  list;
323 
324 	/* Timeout related information */
325 	struct timer_list timer;
326 	struct completion tm_done;
327 	int	          wait_for_comp;
328 	unsigned long	  start_time;
329 	unsigned long	  end_time;
330 	unsigned long	  last_pkt_time;
331 
332 	/* SCSI command and data transfer information */
333 	u32		  data_len;
334 
335 	/* Transport related veriables */
336 	struct fcp_cmnd   cdb_cmd;
337 	size_t		  xfer_len;
338 	u16		  xfer_ddp;
339 	u32		  xfer_contig_end;
340 	u16		  max_payload;
341 
342 	/* SCSI/FCP return status */
343 	u32		  io_status;
344 	u8		  cdb_status;
345 	u8		  status_code;
346 	u8		  scsi_comp_flags;
347 	u32		  req_flags;
348 	u32		  scsi_resid;
349 
350 	/* Associated structures */
351 	struct fc_rport	  *rport;
352 	struct fc_seq	  *seq_ptr;
353 
354 	/* Error Processing information */
355 	u8		  recov_retry;
356 	struct fc_seq	  *recov_seq;
357 };
358 
359 /*
360  * Structure and function definitions for managing Fibre Channel Exchanges
361  * and Sequences
362  *
363  * fc_exch holds state for one exchange and links to its active sequence.
364  *
365  * fc_seq holds the state for an individual sequence.
366  */
367 
368 struct fc_exch_mgr;
369 struct fc_exch_mgr_anchor;
370 extern u16 fc_cpu_mask;	/* cpu mask for possible cpus */
371 
372 /**
373  * struct fc_seq - FC sequence
374  * @id:       The sequence ID
375  * @ssb_stat: Status flags for the sequence status block (SSB)
376  * @cnt:      Number of frames sent so far
377  * @rec_data: FC-4 value for REC
378  */
379 struct fc_seq {
380 	u8  id;
381 	u16 ssb_stat;
382 	u16 cnt;
383 	u32 rec_data;
384 };
385 
386 #define FC_EX_DONE		(1 << 0) /* ep is completed */
387 #define FC_EX_RST_CLEANUP	(1 << 1) /* reset is forcing completion */
388 
389 /**
390  * struct fc_exch - Fibre Channel Exchange
391  * @em:           Exchange manager
392  * @pool:         Exchange pool
393  * @state:        The exchange's state
394  * @xid:          The exchange ID
395  * @ex_list:      Handle used by the EM to track free exchanges
396  * @ex_lock:      Lock that protects the exchange
397  * @ex_refcnt:    Reference count
398  * @timeout_work: Handle for timeout handler
399  * @lp:           The local port that this exchange is on
400  * @oxid:         Originator's exchange ID
401  * @rxid:         Responder's exchange ID
402  * @oid:          Originator's FCID
403  * @sid:          Source FCID
404  * @did:          Destination FCID
405  * @esb_stat:     ESB exchange status
406  * @r_a_tov:      Resouce allocation time out value (in msecs)
407  * @seq_id:       The next sequence ID to use
408  * @f_ctl:        F_CTL flags for the sequence
409  * @fh_type:      The frame type
410  * @class:        The class of service
411  * @seq:          The sequence in use on this exchange
412  * @resp:         Callback for responses on this exchange
413  * @destructor:   Called when destroying the exchange
414  * @arg:          Passed as a void pointer to the resp() callback
415  *
416  * Locking notes: The ex_lock protects following items:
417  *	state, esb_stat, f_ctl, seq.ssb_stat
418  *	seq_id
419  *	sequence allocation
420  */
421 struct fc_exch {
422 	struct fc_exch_mgr  *em;
423 	struct fc_exch_pool *pool;
424 	u32		    state;
425 	u16		    xid;
426 	struct list_head    ex_list;
427 	spinlock_t	    ex_lock;
428 	atomic_t	    ex_refcnt;
429 	struct delayed_work timeout_work;
430 	struct fc_lport	    *lp;
431 	u16		    oxid;
432 	u16		    rxid;
433 	u32		    oid;
434 	u32		    sid;
435 	u32		    did;
436 	u32		    esb_stat;
437 	u32		    r_a_tov;
438 	u8		    seq_id;
439 	u32		    f_ctl;
440 	u8		    fh_type;
441 	enum fc_class	    class;
442 	struct fc_seq	    seq;
443 
444 	void		    (*resp)(struct fc_seq *, struct fc_frame *, void *);
445 	void		    *arg;
446 
447 	void		    (*destructor)(struct fc_seq *, void *);
448 
449 };
450 #define	fc_seq_exch(sp) container_of(sp, struct fc_exch, seq)
451 
452 
453 struct libfc_function_template {
454 	/*
455 	 * Interface to send a FC frame
456 	 *
457 	 * STATUS: REQUIRED
458 	 */
459 	int (*frame_send)(struct fc_lport *, struct fc_frame *);
460 
461 	/*
462 	 * Interface to send ELS/CT frames
463 	 *
464 	 * STATUS: OPTIONAL
465 	 */
466 	struct fc_seq *(*elsct_send)(struct fc_lport *, u32 did,
467 				     struct fc_frame *, unsigned int op,
468 				     void (*resp)(struct fc_seq *,
469 					     struct fc_frame *, void *arg),
470 				     void *arg, u32 timer_msec);
471 
472 	/*
473 	 * Send the FC frame payload using a new exchange and sequence.
474 	 *
475 	 * The exchange response handler is set in this routine to resp()
476 	 * function pointer. It can be called in two scenarios: if a timeout
477 	 * occurs or if a response frame is received for the exchange. The
478 	 * fc_frame pointer in response handler will also indicate timeout
479 	 * as error using IS_ERR related macros.
480 	 *
481 	 * The exchange destructor handler is also set in this routine.
482 	 * The destructor handler is invoked by EM layer when exchange
483 	 * is about to free, this can be used by caller to free its
484 	 * resources along with exchange free.
485 	 *
486 	 * The arg is passed back to resp and destructor handler.
487 	 *
488 	 * The timeout value (in msec) for an exchange is set if non zero
489 	 * timer_msec argument is specified. The timer is canceled when
490 	 * it fires or when the exchange is done. The exchange timeout handler
491 	 * is registered by EM layer.
492 	 *
493 	 * STATUS: OPTIONAL
494 	 */
495 	struct fc_seq *(*exch_seq_send)(struct fc_lport *, struct fc_frame *,
496 					void (*resp)(struct fc_seq *,
497 						     struct fc_frame *,
498 						     void *),
499 					void (*destructor)(struct fc_seq *,
500 							   void *),
501 					void *, unsigned int timer_msec);
502 
503 	/*
504 	 * Sets up the DDP context for a given exchange id on the given
505 	 * scatterlist if LLD supports DDP for large receive.
506 	 *
507 	 * STATUS: OPTIONAL
508 	 */
509 	int (*ddp_setup)(struct fc_lport *, u16, struct scatterlist *,
510 			 unsigned int);
511 	/*
512 	 * Completes the DDP transfer and returns the length of data DDPed
513 	 * for the given exchange id.
514 	 *
515 	 * STATUS: OPTIONAL
516 	 */
517 	int (*ddp_done)(struct fc_lport *, u16);
518 	/*
519 	 * Allow LLD to fill its own Link Error Status Block
520 	 *
521 	 * STATUS: OPTIONAL
522 	 */
523 	void (*get_lesb)(struct fc_lport *, struct fc_els_lesb *lesb);
524 	/*
525 	 * Send a frame using an existing sequence and exchange.
526 	 *
527 	 * STATUS: OPTIONAL
528 	 */
529 	int (*seq_send)(struct fc_lport *, struct fc_seq *,
530 			struct fc_frame *);
531 
532 	/*
533 	 * Send an ELS response using infomation from a previous
534 	 * exchange and sequence.
535 	 *
536 	 * STATUS: OPTIONAL
537 	 */
538 	void (*seq_els_rsp_send)(struct fc_seq *, enum fc_els_cmd,
539 				 struct fc_seq_els_data *);
540 
541 	/*
542 	 * Abort an exchange and sequence. Generally called because of a
543 	 * exchange timeout or an abort from the upper layer.
544 	 *
545 	 * A timer_msec can be specified for abort timeout, if non-zero
546 	 * timer_msec value is specified then exchange resp handler
547 	 * will be called with timeout error if no response to abort.
548 	 *
549 	 * STATUS: OPTIONAL
550 	 */
551 	int (*seq_exch_abort)(const struct fc_seq *,
552 			      unsigned int timer_msec);
553 
554 	/*
555 	 * Indicate that an exchange/sequence tuple is complete and the memory
556 	 * allocated for the related objects may be freed.
557 	 *
558 	 * STATUS: OPTIONAL
559 	 */
560 	void (*exch_done)(struct fc_seq *);
561 
562 	/*
563 	 * Start a new sequence on the same exchange/sequence tuple.
564 	 *
565 	 * STATUS: OPTIONAL
566 	 */
567 	struct fc_seq *(*seq_start_next)(struct fc_seq *);
568 
569 	/*
570 	 * Reset an exchange manager, completing all sequences and exchanges.
571 	 * If s_id is non-zero, reset only exchanges originating from that FID.
572 	 * If d_id is non-zero, reset only exchanges sending to that FID.
573 	 *
574 	 * STATUS: OPTIONAL
575 	 */
576 	void (*exch_mgr_reset)(struct fc_lport *, u32 s_id, u32 d_id);
577 
578 	/*
579 	 * Flush the rport work queue. Generally used before shutdown.
580 	 *
581 	 * STATUS: OPTIONAL
582 	 */
583 	void (*rport_flush_queue)(void);
584 
585 	/*
586 	 * Receive a frame for a local port.
587 	 *
588 	 * STATUS: OPTIONAL
589 	 */
590 	void (*lport_recv)(struct fc_lport *, struct fc_seq *,
591 			   struct fc_frame *);
592 
593 	/*
594 	 * Reset the local port.
595 	 *
596 	 * STATUS: OPTIONAL
597 	 */
598 	int (*lport_reset)(struct fc_lport *);
599 
600 	/*
601 	 * Set the local port FC_ID.
602 	 *
603 	 * This may be provided by the LLD to allow it to be
604 	 * notified when the local port is assigned a FC-ID.
605 	 *
606 	 * The frame, if non-NULL, is the incoming frame with the
607 	 * FLOGI LS_ACC or FLOGI, and may contain the granted MAC
608 	 * address for the LLD.  The frame pointer may be NULL if
609 	 * no MAC is associated with this assignment (LOGO or PLOGI).
610 	 *
611 	 * If FC_ID is non-zero, r_a_tov and e_d_tov must be valid.
612 	 *
613 	 * Note: this is called with the local port mutex held.
614 	 *
615 	 * STATUS: OPTIONAL
616 	 */
617 	void (*lport_set_port_id)(struct fc_lport *, u32 port_id,
618 				  struct fc_frame *);
619 
620 	/*
621 	 * Create a remote port with a given port ID
622 	 *
623 	 * STATUS: OPTIONAL
624 	 */
625 	struct fc_rport_priv *(*rport_create)(struct fc_lport *, u32);
626 
627 	/*
628 	 * Initiates the RP state machine. It is called from the LP module.
629 	 * This function will issue the following commands to the N_Port
630 	 * identified by the FC ID provided.
631 	 *
632 	 * - PLOGI
633 	 * - PRLI
634 	 * - RTV
635 	 *
636 	 * STATUS: OPTIONAL
637 	 */
638 	int (*rport_login)(struct fc_rport_priv *);
639 
640 	/*
641 	 * Logoff, and remove the rport from the transport if
642 	 * it had been added. This will send a LOGO to the target.
643 	 *
644 	 * STATUS: OPTIONAL
645 	 */
646 	int (*rport_logoff)(struct fc_rport_priv *);
647 
648 	/*
649 	 * Recieve a request from a remote port.
650 	 *
651 	 * STATUS: OPTIONAL
652 	 */
653 	void (*rport_recv_req)(struct fc_seq *, struct fc_frame *,
654 			       struct fc_lport *);
655 
656 	/*
657 	 * lookup an rport by it's port ID.
658 	 *
659 	 * STATUS: OPTIONAL
660 	 */
661 	struct fc_rport_priv *(*rport_lookup)(const struct fc_lport *, u32);
662 
663 	/*
664 	 * Destroy an rport after final kref_put().
665 	 * The argument is a pointer to the kref inside the fc_rport_priv.
666 	 */
667 	void (*rport_destroy)(struct kref *);
668 
669 	/*
670 	 * Send a fcp cmd from fsp pkt.
671 	 * Called with the SCSI host lock unlocked and irqs disabled.
672 	 *
673 	 * The resp handler is called when FCP_RSP received.
674 	 *
675 	 * STATUS: OPTIONAL
676 	 */
677 	int (*fcp_cmd_send)(struct fc_lport *, struct fc_fcp_pkt *,
678 			    void (*resp)(struct fc_seq *, struct fc_frame *,
679 					 void *));
680 
681 	/*
682 	 * Cleanup the FCP layer, used durring link down and reset
683 	 *
684 	 * STATUS: OPTIONAL
685 	 */
686 	void (*fcp_cleanup)(struct fc_lport *);
687 
688 	/*
689 	 * Abort all I/O on a local port
690 	 *
691 	 * STATUS: OPTIONAL
692 	 */
693 	void (*fcp_abort_io)(struct fc_lport *);
694 
695 	/*
696 	 * Receive a request for the discovery layer.
697 	 *
698 	 * STATUS: OPTIONAL
699 	 */
700 	void (*disc_recv_req)(struct fc_seq *, struct fc_frame *,
701 			      struct fc_lport *);
702 
703 	/*
704 	 * Start discovery for a local port.
705 	 *
706 	 * STATUS: OPTIONAL
707 	 */
708 	void (*disc_start)(void (*disc_callback)(struct fc_lport *,
709 						 enum fc_disc_event),
710 			   struct fc_lport *);
711 
712 	/*
713 	 * Stop discovery for a given lport. This will remove
714 	 * all discovered rports
715 	 *
716 	 * STATUS: OPTIONAL
717 	 */
718 	void (*disc_stop) (struct fc_lport *);
719 
720 	/*
721 	 * Stop discovery for a given lport. This will block
722 	 * until all discovered rports are deleted from the
723 	 * FC transport class
724 	 *
725 	 * STATUS: OPTIONAL
726 	 */
727 	void (*disc_stop_final) (struct fc_lport *);
728 };
729 
730 /**
731  * struct fc_disc - Discovery context
732  * @retry_count:   Number of retries
733  * @pending:       1 if discovery is pending, 0 if not
734  * @requesting:    1 if discovery has been requested, 0 if not
735  * @seq_count:     Number of sequences used for discovery
736  * @buf_len:       Length of the discovery buffer
737  * @disc_id:       Discovery ID
738  * @rports:        List of discovered remote ports
739  * @lport:         The local port that discovery is for
740  * @disc_mutex:    Mutex that protects the discovery context
741  * @partial_buf:   Partial name buffer (if names are returned
742  *                 in multiple frames)
743  * @disc_work:     handle for delayed work context
744  * @disc_callback: Callback routine called when discovery completes
745  */
746 struct fc_disc {
747 	unsigned char         retry_count;
748 	unsigned char         pending;
749 	unsigned char         requested;
750 	unsigned short        seq_count;
751 	unsigned char         buf_len;
752 	u16                   disc_id;
753 
754 	struct list_head      rports;
755 	struct fc_lport	      *lport;
756 	struct mutex	      disc_mutex;
757 	struct fc_gpn_ft_resp partial_buf;
758 	struct delayed_work   disc_work;
759 
760 	void (*disc_callback)(struct fc_lport *,
761 			      enum fc_disc_event);
762 };
763 
764 /**
765  * struct fc_lport - Local port
766  * @host:                  The SCSI host associated with a local port
767  * @ema_list:              Exchange manager anchor list
768  * @dns_rdata:             The directory server remote port
769  * @ptp_rdata:             Point to point remote port
770  * @scsi_priv:             FCP layer internal data
771  * @disc:                  Discovery context
772  * @vports:                Child vports if N_Port
773  * @vport:                 Parent vport if VN_Port
774  * @tt:                    Libfc function template
775  * @link_up:               Link state (1 = link up, 0 = link down)
776  * @qfull:                 Queue state (1 queue is full, 0 queue is not full)
777  * @state:                 Identifies the state
778  * @boot_time:             Timestamp indicating when the local port came online
779  * @host_stats:            SCSI host statistics
780  * @dev_stats:             FCoE device stats (TODO: libfc should not be
781  *                         FCoE aware)
782  * @retry_count:           Number of retries in the current state
783  * @port_id:               FC Port ID
784  * @wwpn:                  World Wide Port Name
785  * @wwnn:                  World Wide Node Name
786  * @service_params:        Common service parameters
787  * @e_d_tov:               Error detection timeout value
788  * @r_a_tov:               Resouce allocation timeout value
789  * @rnid_gen:              RNID information
790  * @sg_supp:               Indicates if scatter gather is supported
791  * @seq_offload:           Indicates if sequence offload is supported
792  * @crc_offload:           Indicates if CRC offload is supported
793  * @lro_enabled:           Indicates if large receive offload is supported
794  * @does_npiv:             Supports multiple vports
795  * @npiv_enabled:          Switch/fabric allows NPIV
796  * @mfs:                   The maximum Fibre Channel payload size
797  * @max_retry_count:       The maximum retry attempts
798  * @max_rport_retry_count: The maximum remote port retry attempts
799  * @lro_xid:               The maximum XID for LRO
800  * @lso_max:               The maximum large offload send size
801  * @fcts:                  FC-4 type mask
802  * @lp_mutex:              Mutex to protect the local port
803  * @list:                  Handle for list of local ports
804  * @retry_work:            Handle to local port for delayed retry context
805  */
806 struct fc_lport {
807 	/* Associations */
808 	struct Scsi_Host	       *host;
809 	struct list_head	       ema_list;
810 	struct fc_rport_priv	       *dns_rdata;
811 	struct fc_rport_priv	       *ptp_rdata;
812 	void			       *scsi_priv;
813 	struct fc_disc                 disc;
814 
815 	/* Virtual port information */
816 	struct list_head	       vports;
817 	struct fc_vport		       *vport;
818 
819 	/* Operational Information */
820 	struct libfc_function_template tt;
821 	u8			       link_up;
822 	u8			       qfull;
823 	enum fc_lport_state	       state;
824 	unsigned long		       boot_time;
825 	struct fc_host_statistics      host_stats;
826 	struct fcoe_dev_stats	       *dev_stats;
827 	u8			       retry_count;
828 
829 	/* Fabric information */
830 	u32                            port_id;
831 	u64			       wwpn;
832 	u64			       wwnn;
833 	unsigned int		       service_params;
834 	unsigned int		       e_d_tov;
835 	unsigned int		       r_a_tov;
836 	struct fc_els_rnid_gen	       rnid_gen;
837 
838 	/* Capabilities */
839 	u32			       sg_supp:1;
840 	u32			       seq_offload:1;
841 	u32			       crc_offload:1;
842 	u32			       lro_enabled:1;
843 	u32			       does_npiv:1;
844 	u32			       npiv_enabled:1;
845 	u32			       mfs;
846 	u8			       max_retry_count;
847 	u8			       max_rport_retry_count;
848 	u16			       link_speed;
849 	u16			       link_supported_speeds;
850 	u16			       lro_xid;
851 	unsigned int		       lso_max;
852 	struct fc_ns_fts	       fcts;
853 
854 	/* Miscellaneous */
855 	struct mutex                   lp_mutex;
856 	struct list_head               list;
857 	struct delayed_work	       retry_work;
858 };
859 
860 /*
861  * FC_LPORT HELPER FUNCTIONS
862  *****************************/
863 
864 /**
865  * fc_lport_test_ready() - Determine if a local port is in the READY state
866  * @lport: The local port to test
867  */
868 static inline int fc_lport_test_ready(struct fc_lport *lport)
869 {
870 	return lport->state == LPORT_ST_READY;
871 }
872 
873 /**
874  * fc_set_wwnn() - Set the World Wide Node Name of a local port
875  * @lport: The local port whose WWNN is to be set
876  * @wwnn:  The new WWNN
877  */
878 static inline void fc_set_wwnn(struct fc_lport *lport, u64 wwnn)
879 {
880 	lport->wwnn = wwnn;
881 }
882 
883 /**
884  * fc_set_wwpn() - Set the World Wide Port Name of a local port
885  * @lport: The local port whose WWPN is to be set
886  * @wwnn:  The new WWPN
887  */
888 static inline void fc_set_wwpn(struct fc_lport *lport, u64 wwnn)
889 {
890 	lport->wwpn = wwnn;
891 }
892 
893 /**
894  * fc_lport_state_enter() - Change a local port's state
895  * @lport: The local port whose state is to change
896  * @state: The new state
897  */
898 static inline void fc_lport_state_enter(struct fc_lport *lport,
899 					enum fc_lport_state state)
900 {
901 	if (state != lport->state)
902 		lport->retry_count = 0;
903 	lport->state = state;
904 }
905 
906 /**
907  * fc_lport_init_stats() - Allocate per-CPU statistics for a local port
908  * @lport: The local port whose statistics are to be initialized
909  */
910 static inline int fc_lport_init_stats(struct fc_lport *lport)
911 {
912 	lport->dev_stats = alloc_percpu(struct fcoe_dev_stats);
913 	if (!lport->dev_stats)
914 		return -ENOMEM;
915 	return 0;
916 }
917 
918 /**
919  * fc_lport_free_stats() - Free memory for a local port's statistics
920  * @lport: The local port whose statistics are to be freed
921  */
922 static inline void fc_lport_free_stats(struct fc_lport *lport)
923 {
924 	free_percpu(lport->dev_stats);
925 }
926 
927 /**
928  * lport_priv() - Return the private data from a local port
929  * @lport: The local port whose private data is to be retreived
930  */
931 static inline void *lport_priv(const struct fc_lport *lport)
932 {
933 	return (void *)(lport + 1);
934 }
935 
936 /**
937  * libfc_host_alloc() - Allocate a Scsi_Host with room for a local port and
938  *                      LLD private data
939  * @sht:       The SCSI host template
940  * @priv_size: Size of private data
941  *
942  * Returns: libfc lport
943  */
944 static inline struct fc_lport *
945 libfc_host_alloc(struct scsi_host_template *sht, int priv_size)
946 {
947 	struct fc_lport *lport;
948 	struct Scsi_Host *shost;
949 
950 	shost = scsi_host_alloc(sht, sizeof(*lport) + priv_size);
951 	if (!shost)
952 		return NULL;
953 	lport = shost_priv(shost);
954 	lport->host = shost;
955 	INIT_LIST_HEAD(&lport->ema_list);
956 	INIT_LIST_HEAD(&lport->vports);
957 	return lport;
958 }
959 
960 /*
961  * FC_FCP HELPER FUNCTIONS
962  *****************************/
963 static inline bool fc_fcp_is_read(const struct fc_fcp_pkt *fsp)
964 {
965 	if (fsp && fsp->cmd)
966 		return fsp->cmd->sc_data_direction == DMA_FROM_DEVICE;
967 	return false;
968 }
969 
970 /*
971  * LOCAL PORT LAYER
972  *****************************/
973 int fc_lport_init(struct fc_lport *);
974 int fc_lport_destroy(struct fc_lport *);
975 int fc_fabric_logoff(struct fc_lport *);
976 int fc_fabric_login(struct fc_lport *);
977 void __fc_linkup(struct fc_lport *);
978 void fc_linkup(struct fc_lport *);
979 void __fc_linkdown(struct fc_lport *);
980 void fc_linkdown(struct fc_lport *);
981 void fc_vport_setlink(struct fc_lport *);
982 void fc_vports_linkchange(struct fc_lport *);
983 int fc_lport_config(struct fc_lport *);
984 int fc_lport_reset(struct fc_lport *);
985 int fc_set_mfs(struct fc_lport *, u32 mfs);
986 struct fc_lport *libfc_vport_create(struct fc_vport *, int privsize);
987 struct fc_lport *fc_vport_id_lookup(struct fc_lport *, u32 port_id);
988 int fc_lport_bsg_request(struct fc_bsg_job *);
989 
990 /*
991  * REMOTE PORT LAYER
992  *****************************/
993 int fc_rport_init(struct fc_lport *);
994 void fc_rport_terminate_io(struct fc_rport *);
995 
996 /*
997  * DISCOVERY LAYER
998  *****************************/
999 int fc_disc_init(struct fc_lport *);
1000 
1001 /*
1002  * FCP LAYER
1003  *****************************/
1004 int fc_fcp_init(struct fc_lport *);
1005 void fc_fcp_destroy(struct fc_lport *);
1006 
1007 /*
1008  * SCSI INTERACTION LAYER
1009  *****************************/
1010 int fc_queuecommand(struct scsi_cmnd *,
1011 		    void (*done)(struct scsi_cmnd *));
1012 int fc_eh_abort(struct scsi_cmnd *);
1013 int fc_eh_device_reset(struct scsi_cmnd *);
1014 int fc_eh_host_reset(struct scsi_cmnd *);
1015 int fc_slave_alloc(struct scsi_device *);
1016 int fc_change_queue_depth(struct scsi_device *, int qdepth, int reason);
1017 int fc_change_queue_type(struct scsi_device *, int tag_type);
1018 
1019 /*
1020  * ELS/CT interface
1021  *****************************/
1022 int fc_elsct_init(struct fc_lport *);
1023 struct fc_seq *fc_elsct_send(struct fc_lport *, u32 did,
1024 				    struct fc_frame *,
1025 				    unsigned int op,
1026 				    void (*resp)(struct fc_seq *,
1027 						 struct fc_frame *,
1028 						 void *arg),
1029 				    void *arg, u32 timer_msec);
1030 void fc_lport_flogi_resp(struct fc_seq *, struct fc_frame *, void *);
1031 void fc_lport_logo_resp(struct fc_seq *, struct fc_frame *, void *);
1032 
1033 
1034 /*
1035  * EXCHANGE MANAGER LAYER
1036  *****************************/
1037 int fc_exch_init(struct fc_lport *);
1038 struct fc_exch_mgr_anchor *fc_exch_mgr_add(struct fc_lport *,
1039 					   struct fc_exch_mgr *,
1040 					   bool (*match)(struct fc_frame *));
1041 void fc_exch_mgr_del(struct fc_exch_mgr_anchor *);
1042 int fc_exch_mgr_list_clone(struct fc_lport *src, struct fc_lport *dst);
1043 struct fc_exch_mgr *fc_exch_mgr_alloc(struct fc_lport *, enum fc_class class,
1044 				      u16 min_xid, u16 max_xid,
1045 				      bool (*match)(struct fc_frame *));
1046 void fc_exch_mgr_free(struct fc_lport *);
1047 void fc_exch_recv(struct fc_lport *, struct fc_frame *);
1048 void fc_exch_mgr_reset(struct fc_lport *, u32 s_id, u32 d_id);
1049 
1050 /*
1051  * Functions for fc_functions_template
1052  */
1053 void fc_get_host_speed(struct Scsi_Host *);
1054 void fc_get_host_port_state(struct Scsi_Host *);
1055 void fc_set_rport_loss_tmo(struct fc_rport *, u32 timeout);
1056 struct fc_host_statistics *fc_get_host_stats(struct Scsi_Host *);
1057 
1058 #endif /* _LIBFC_H_ */
1059