xref: /linux/include/scsi/libfc.h (revision edcbb4395ecd2f2731fbf38ecbff5be0316513cb)
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_FLOGI:   Waiting for FLOGI completion for point-to-multipoint
101  * @RPORT_ST_PLOGI_WAIT:   Waiting for peer to login for point-to-multipoint
102  * @RPORT_ST_PLOGI:   Waiting for PLOGI completion
103  * @RPORT_ST_PRLI:    Waiting for PRLI completion
104  * @RPORT_ST_RTV:     Waiting for RTV completion
105  * @RPORT_ST_READY:   Ready for use
106  * @RPORT_ST_LOGO:    Remote port logout (LOGO) sent
107  * @RPORT_ST_ADISC:   Discover Address sent
108  * @RPORT_ST_DELETE:  Remote port being deleted
109 */
110 enum fc_rport_state {
111 	RPORT_ST_INIT,
112 	RPORT_ST_FLOGI,
113 	RPORT_ST_PLOGI_WAIT,
114 	RPORT_ST_PLOGI,
115 	RPORT_ST_PRLI,
116 	RPORT_ST_RTV,
117 	RPORT_ST_READY,
118 	RPORT_ST_LOGO,
119 	RPORT_ST_ADISC,
120 	RPORT_ST_DELETE,
121 };
122 
123 /**
124  * struct fc_disc_port - temporary discovery port to hold rport identifiers
125  * @lp:         Fibre Channel host port instance
126  * @peers:      Node for list management during discovery and RSCN processing
127  * @rport_work: Work struct for starting the rport state machine
128  * @port_id:    Port ID of the discovered port
129  */
130 struct fc_disc_port {
131 	struct fc_lport    *lp;
132 	struct list_head   peers;
133 	struct work_struct rport_work;
134 	u32                port_id;
135 };
136 
137 /**
138  * enum fc_rport_event - Remote port events
139  * @RPORT_EV_NONE:   No event
140  * @RPORT_EV_READY:  Remote port is ready for use
141  * @RPORT_EV_FAILED: State machine failed, remote port is not ready
142  * @RPORT_EV_STOP:   Remote port has been stopped
143  * @RPORT_EV_LOGO:   Remote port logout (LOGO) sent
144  */
145 enum fc_rport_event {
146 	RPORT_EV_NONE = 0,
147 	RPORT_EV_READY,
148 	RPORT_EV_FAILED,
149 	RPORT_EV_STOP,
150 	RPORT_EV_LOGO
151 };
152 
153 struct fc_rport_priv;
154 
155 /**
156  * struct fc_rport_operations - Operations for a remote port
157  * @event_callback: Function to be called for remote port events
158  */
159 struct fc_rport_operations {
160 	void (*event_callback)(struct fc_lport *, struct fc_rport_priv *,
161 			       enum fc_rport_event);
162 };
163 
164 /**
165  * struct fc_rport_libfc_priv - libfc internal information about a remote port
166  * @local_port: The associated local port
167  * @rp_state:   Indicates READY for I/O or DELETE when blocked
168  * @flags:      REC and RETRY supported flags
169  * @e_d_tov:    Error detect timeout value (in msec)
170  * @r_a_tov:    Resource allocation timeout value (in msec)
171  */
172 struct fc_rport_libfc_priv {
173 	struct fc_lport		   *local_port;
174 	enum fc_rport_state        rp_state;
175 	u16			   flags;
176 	#define FC_RP_FLAGS_REC_SUPPORTED	(1 << 0)
177 	#define FC_RP_FLAGS_RETRY		(1 << 1)
178 	#define FC_RP_STARTED			(1 << 2)
179 	unsigned int	           e_d_tov;
180 	unsigned int	           r_a_tov;
181 };
182 
183 /**
184  * struct fc_rport_priv - libfc remote port and discovery info
185  * @local_port:     The associated local port
186  * @rport:          The FC transport remote port
187  * @kref:           Reference counter
188  * @rp_state:       Enumeration that tracks progress of PLOGI, PRLI,
189  *                  and RTV exchanges
190  * @ids:            The remote port identifiers and roles
191  * @flags:          STARTED, REC and RETRY_SUPPORTED flags
192  * @max_seq:        Maximum number of concurrent sequences
193  * @disc_id:        The discovery identifier
194  * @maxframe_size:  The maximum frame size
195  * @retries:        The retry count for the current state
196  * @major_retries:  The retry count for the entire PLOGI/PRLI state machine
197  * @e_d_tov:        Error detect timeout value (in msec)
198  * @r_a_tov:        Resource allocation timeout value (in msec)
199  * @rp_mutex:       The mutex that protects the remote port
200  * @retry_work:     Handle for retries
201  * @event_callback: Callback when READY, FAILED or LOGO states complete
202  * @rcu:	    Structure used for freeing in an RCU-safe manner
203  */
204 struct fc_rport_priv {
205 	struct fc_lport		    *local_port;
206 	struct fc_rport		    *rport;
207 	struct kref		    kref;
208 	enum fc_rport_state         rp_state;
209 	struct fc_rport_identifiers ids;
210 	u16			    flags;
211 	u16		            max_seq;
212 	u16			    disc_id;
213 	u16			    maxframe_size;
214 	unsigned int	            retries;
215 	unsigned int	            major_retries;
216 	unsigned int	            e_d_tov;
217 	unsigned int	            r_a_tov;
218 	struct mutex                rp_mutex;
219 	struct delayed_work	    retry_work;
220 	enum fc_rport_event         event;
221 	struct fc_rport_operations  *ops;
222 	struct list_head            peers;
223 	struct work_struct          event_work;
224 	u32			    supported_classes;
225 	struct rcu_head		    rcu;
226 };
227 
228 /**
229  * struct fcoe_dev_stats - fcoe stats structure
230  * @SecondsSinceLastReset: Seconds since the last reset
231  * @TxFrames:              Number of transmitted frames
232  * @TxWords:               Number of transmitted words
233  * @RxFrames:              Number of received frames
234  * @RxWords:               Number of received words
235  * @ErrorFrames:           Number of received error frames
236  * @DumpedFrames:          Number of dumped frames
237  * @LinkFailureCount:      Number of link failures
238  * @LossOfSignalCount:     Number for signal losses
239  * @InvalidTxWordCount:    Number of invalid transmitted words
240  * @InvalidCRCCount:       Number of invalid CRCs
241  * @InputRequests:         Number of input requests
242  * @OutputRequests:        Number of output requests
243  * @ControlRequests:       Number of control requests
244  * @InputMegabytes:        Number of received megabytes
245  * @OutputMegabytes:       Number of transmitted megabytes
246  * @VLinkFailureCount:     Number of virtual link failures
247  * @MissDiscAdvCount:      Number of missing FIP discovery advertisement
248  */
249 struct fcoe_dev_stats {
250 	u64		SecondsSinceLastReset;
251 	u64		TxFrames;
252 	u64		TxWords;
253 	u64		RxFrames;
254 	u64		RxWords;
255 	u64		ErrorFrames;
256 	u64		DumpedFrames;
257 	u64		LinkFailureCount;
258 	u64		LossOfSignalCount;
259 	u64		InvalidTxWordCount;
260 	u64		InvalidCRCCount;
261 	u64		InputRequests;
262 	u64		OutputRequests;
263 	u64		ControlRequests;
264 	u64		InputMegabytes;
265 	u64		OutputMegabytes;
266 	u64		VLinkFailureCount;
267 	u64		MissDiscAdvCount;
268 };
269 
270 /**
271  * struct fc_seq_els_data - ELS data used for passing ELS specific responses
272  * @fp:     The ELS frame
273  * @reason: The reason for rejection
274  * @explan: The explaination of the rejection
275  *
276  * Mainly used by the exchange manager layer.
277  */
278 struct fc_seq_els_data {
279 	struct fc_frame *fp;
280 	enum fc_els_rjt_reason reason;
281 	enum fc_els_rjt_explan explan;
282 };
283 
284 /**
285  * struct fc_fcp_pkt - FCP request structure (one for each scsi_cmnd request)
286  * @lp:              The associated local port
287  * @state:           The state of the I/O
288  * @tgt_flags:       Target's flags
289  * @ref_cnt:         Reference count
290  * @scsi_pkt_lock:   Lock to protect the SCSI packet (must be taken before the
291  *                   host_lock if both are to be held at the same time)
292  * @cmd:             The SCSI command (set and clear with the host_lock held)
293  * @list:            Tracks queued commands (accessed with the host_lock held)
294  * @timer:           The command timer
295  * @tm_done:         Completion indicator
296  * @wait_for_comp:   Indicator to wait for completion of the I/O (in jiffies)
297  * @start_time:      Timestamp indicating the start of the I/O (in jiffies)
298  * @end_time:        Timestamp indicating the end of the I/O (in jiffies)
299  * @last_pkt_time:   Timestamp of the last frame received (in jiffies)
300  * @data_len:        The length of the data
301  * @cdb_cmd:         The CDB command
302  * @xfer_len:        The transfer length
303  * @xfer_ddp:        Indicates if this transfer used DDP (XID of the exchange
304  *                   will be set here if DDP was setup)
305  * @xfer_contig_end: The offset into the buffer if the buffer is contiguous
306  *                   (Tx and Rx)
307  * @max_payload:     The maximum payload size (in bytes)
308  * @io_status:       SCSI result (upper 24 bits)
309  * @cdb_status:      CDB status
310  * @status_code:     FCP I/O status
311  * @scsi_comp_flags: Completion flags (bit 3 Underrun bit 2: overrun)
312  * @req_flags:       Request flags (bit 0: read bit:1 write)
313  * @scsi_resid:      SCSI residule length
314  * @rport:           The remote port that the SCSI command is targeted at
315  * @seq_ptr:         The sequence that will carry the SCSI command
316  * @recov_retry:     Number of recovery retries
317  * @recov_seq:       The sequence for REC or SRR
318  */
319 struct fc_fcp_pkt {
320 	/* Housekeeping information */
321 	struct fc_lport   *lp;
322 	u16		  state;
323 	u16		  tgt_flags;
324 	atomic_t	  ref_cnt;
325 	spinlock_t	  scsi_pkt_lock;
326 
327 	/* SCSI I/O related information */
328 	struct scsi_cmnd  *cmd;
329 	struct list_head  list;
330 
331 	/* Timeout related information */
332 	struct timer_list timer;
333 	struct completion tm_done;
334 	int	          wait_for_comp;
335 	unsigned long	  start_time;
336 	unsigned long	  end_time;
337 	unsigned long	  last_pkt_time;
338 
339 	/* SCSI command and data transfer information */
340 	u32		  data_len;
341 
342 	/* Transport related veriables */
343 	struct fcp_cmnd   cdb_cmd;
344 	size_t		  xfer_len;
345 	u16		  xfer_ddp;
346 	u32		  xfer_contig_end;
347 	u16		  max_payload;
348 
349 	/* SCSI/FCP return status */
350 	u32		  io_status;
351 	u8		  cdb_status;
352 	u8		  status_code;
353 	u8		  scsi_comp_flags;
354 	u32		  req_flags;
355 	u32		  scsi_resid;
356 
357 	/* Associated structures */
358 	struct fc_rport	  *rport;
359 	struct fc_seq	  *seq_ptr;
360 
361 	/* Error Processing information */
362 	u8		  recov_retry;
363 	struct fc_seq	  *recov_seq;
364 };
365 
366 /*
367  * Structure and function definitions for managing Fibre Channel Exchanges
368  * and Sequences
369  *
370  * fc_exch holds state for one exchange and links to its active sequence.
371  *
372  * fc_seq holds the state for an individual sequence.
373  */
374 
375 struct fc_exch_mgr;
376 struct fc_exch_mgr_anchor;
377 extern u16 fc_cpu_mask;	/* cpu mask for possible cpus */
378 
379 /**
380  * struct fc_seq - FC sequence
381  * @id:       The sequence ID
382  * @ssb_stat: Status flags for the sequence status block (SSB)
383  * @cnt:      Number of frames sent so far
384  * @rec_data: FC-4 value for REC
385  */
386 struct fc_seq {
387 	u8  id;
388 	u16 ssb_stat;
389 	u16 cnt;
390 	u32 rec_data;
391 };
392 
393 #define FC_EX_DONE		(1 << 0) /* ep is completed */
394 #define FC_EX_RST_CLEANUP	(1 << 1) /* reset is forcing completion */
395 
396 /**
397  * struct fc_exch - Fibre Channel Exchange
398  * @em:           Exchange manager
399  * @pool:         Exchange pool
400  * @state:        The exchange's state
401  * @xid:          The exchange ID
402  * @ex_list:      Handle used by the EM to track free exchanges
403  * @ex_lock:      Lock that protects the exchange
404  * @ex_refcnt:    Reference count
405  * @timeout_work: Handle for timeout handler
406  * @lp:           The local port that this exchange is on
407  * @oxid:         Originator's exchange ID
408  * @rxid:         Responder's exchange ID
409  * @oid:          Originator's FCID
410  * @sid:          Source FCID
411  * @did:          Destination FCID
412  * @esb_stat:     ESB exchange status
413  * @r_a_tov:      Resouce allocation time out value (in msecs)
414  * @seq_id:       The next sequence ID to use
415  * @encaps:       encapsulation information for lower-level driver
416  * @f_ctl:        F_CTL flags for the sequence
417  * @fh_type:      The frame type
418  * @class:        The class of service
419  * @seq:          The sequence in use on this exchange
420  * @resp:         Callback for responses on this exchange
421  * @destructor:   Called when destroying the exchange
422  * @arg:          Passed as a void pointer to the resp() callback
423  *
424  * Locking notes: The ex_lock protects following items:
425  *	state, esb_stat, f_ctl, seq.ssb_stat
426  *	seq_id
427  *	sequence allocation
428  */
429 struct fc_exch {
430 	struct fc_exch_mgr  *em;
431 	struct fc_exch_pool *pool;
432 	u32		    state;
433 	u16		    xid;
434 	struct list_head    ex_list;
435 	spinlock_t	    ex_lock;
436 	atomic_t	    ex_refcnt;
437 	struct delayed_work timeout_work;
438 	struct fc_lport	    *lp;
439 	u16		    oxid;
440 	u16		    rxid;
441 	u32		    oid;
442 	u32		    sid;
443 	u32		    did;
444 	u32		    esb_stat;
445 	u32		    r_a_tov;
446 	u8		    seq_id;
447 	u8		    encaps;
448 	u32		    f_ctl;
449 	u8		    fh_type;
450 	enum fc_class	    class;
451 	struct fc_seq	    seq;
452 
453 	void		    (*resp)(struct fc_seq *, struct fc_frame *, void *);
454 	void		    *arg;
455 
456 	void		    (*destructor)(struct fc_seq *, void *);
457 
458 };
459 #define	fc_seq_exch(sp) container_of(sp, struct fc_exch, seq)
460 
461 
462 struct libfc_function_template {
463 	/*
464 	 * Interface to send a FC frame
465 	 *
466 	 * STATUS: REQUIRED
467 	 */
468 	int (*frame_send)(struct fc_lport *, struct fc_frame *);
469 
470 	/*
471 	 * Interface to send ELS/CT frames
472 	 *
473 	 * STATUS: OPTIONAL
474 	 */
475 	struct fc_seq *(*elsct_send)(struct fc_lport *, u32 did,
476 				     struct fc_frame *, unsigned int op,
477 				     void (*resp)(struct fc_seq *,
478 					     struct fc_frame *, void *arg),
479 				     void *arg, u32 timer_msec);
480 
481 	/*
482 	 * Send the FC frame payload using a new exchange and sequence.
483 	 *
484 	 * The exchange response handler is set in this routine to resp()
485 	 * function pointer. It can be called in two scenarios: if a timeout
486 	 * occurs or if a response frame is received for the exchange. The
487 	 * fc_frame pointer in response handler will also indicate timeout
488 	 * as error using IS_ERR related macros.
489 	 *
490 	 * The exchange destructor handler is also set in this routine.
491 	 * The destructor handler is invoked by EM layer when exchange
492 	 * is about to free, this can be used by caller to free its
493 	 * resources along with exchange free.
494 	 *
495 	 * The arg is passed back to resp and destructor handler.
496 	 *
497 	 * The timeout value (in msec) for an exchange is set if non zero
498 	 * timer_msec argument is specified. The timer is canceled when
499 	 * it fires or when the exchange is done. The exchange timeout handler
500 	 * is registered by EM layer.
501 	 *
502 	 * STATUS: OPTIONAL
503 	 */
504 	struct fc_seq *(*exch_seq_send)(struct fc_lport *, struct fc_frame *,
505 					void (*resp)(struct fc_seq *,
506 						     struct fc_frame *,
507 						     void *),
508 					void (*destructor)(struct fc_seq *,
509 							   void *),
510 					void *, unsigned int timer_msec);
511 
512 	/*
513 	 * Sets up the DDP context for a given exchange id on the given
514 	 * scatterlist if LLD supports DDP for large receive.
515 	 *
516 	 * STATUS: OPTIONAL
517 	 */
518 	int (*ddp_setup)(struct fc_lport *, u16, struct scatterlist *,
519 			 unsigned int);
520 	/*
521 	 * Completes the DDP transfer and returns the length of data DDPed
522 	 * for the given exchange id.
523 	 *
524 	 * STATUS: OPTIONAL
525 	 */
526 	int (*ddp_done)(struct fc_lport *, u16);
527 	/*
528 	 * Allow LLD to fill its own Link Error Status Block
529 	 *
530 	 * STATUS: OPTIONAL
531 	 */
532 	void (*get_lesb)(struct fc_lport *, struct fc_els_lesb *lesb);
533 	/*
534 	 * Send a frame using an existing sequence and exchange.
535 	 *
536 	 * STATUS: OPTIONAL
537 	 */
538 	int (*seq_send)(struct fc_lport *, struct fc_seq *,
539 			struct fc_frame *);
540 
541 	/*
542 	 * Send an ELS response using infomation from a previous
543 	 * exchange and sequence.
544 	 *
545 	 * STATUS: OPTIONAL
546 	 */
547 	void (*seq_els_rsp_send)(struct fc_seq *, enum fc_els_cmd,
548 				 struct fc_seq_els_data *);
549 
550 	/*
551 	 * Abort an exchange and sequence. Generally called because of a
552 	 * exchange timeout or an abort from the upper layer.
553 	 *
554 	 * A timer_msec can be specified for abort timeout, if non-zero
555 	 * timer_msec value is specified then exchange resp handler
556 	 * will be called with timeout error if no response to abort.
557 	 *
558 	 * STATUS: OPTIONAL
559 	 */
560 	int (*seq_exch_abort)(const struct fc_seq *,
561 			      unsigned int timer_msec);
562 
563 	/*
564 	 * Indicate that an exchange/sequence tuple is complete and the memory
565 	 * allocated for the related objects may be freed.
566 	 *
567 	 * STATUS: OPTIONAL
568 	 */
569 	void (*exch_done)(struct fc_seq *);
570 
571 	/*
572 	 * Start a new sequence on the same exchange/sequence tuple.
573 	 *
574 	 * STATUS: OPTIONAL
575 	 */
576 	struct fc_seq *(*seq_start_next)(struct fc_seq *);
577 
578 	/*
579 	 * Reset an exchange manager, completing all sequences and exchanges.
580 	 * If s_id is non-zero, reset only exchanges originating from that FID.
581 	 * If d_id is non-zero, reset only exchanges sending to that FID.
582 	 *
583 	 * STATUS: OPTIONAL
584 	 */
585 	void (*exch_mgr_reset)(struct fc_lport *, u32 s_id, u32 d_id);
586 
587 	/*
588 	 * Flush the rport work queue. Generally used before shutdown.
589 	 *
590 	 * STATUS: OPTIONAL
591 	 */
592 	void (*rport_flush_queue)(void);
593 
594 	/*
595 	 * Receive a frame for a local port.
596 	 *
597 	 * STATUS: OPTIONAL
598 	 */
599 	void (*lport_recv)(struct fc_lport *, struct fc_seq *,
600 			   struct fc_frame *);
601 
602 	/*
603 	 * Reset the local port.
604 	 *
605 	 * STATUS: OPTIONAL
606 	 */
607 	int (*lport_reset)(struct fc_lport *);
608 
609 	/*
610 	 * Set the local port FC_ID.
611 	 *
612 	 * This may be provided by the LLD to allow it to be
613 	 * notified when the local port is assigned a FC-ID.
614 	 *
615 	 * The frame, if non-NULL, is the incoming frame with the
616 	 * FLOGI LS_ACC or FLOGI, and may contain the granted MAC
617 	 * address for the LLD.  The frame pointer may be NULL if
618 	 * no MAC is associated with this assignment (LOGO or PLOGI).
619 	 *
620 	 * If FC_ID is non-zero, r_a_tov and e_d_tov must be valid.
621 	 *
622 	 * Note: this is called with the local port mutex held.
623 	 *
624 	 * STATUS: OPTIONAL
625 	 */
626 	void (*lport_set_port_id)(struct fc_lport *, u32 port_id,
627 				  struct fc_frame *);
628 
629 	/*
630 	 * Create a remote port with a given port ID
631 	 *
632 	 * STATUS: OPTIONAL
633 	 */
634 	struct fc_rport_priv *(*rport_create)(struct fc_lport *, u32);
635 
636 	/*
637 	 * Initiates the RP state machine. It is called from the LP module.
638 	 * This function will issue the following commands to the N_Port
639 	 * identified by the FC ID provided.
640 	 *
641 	 * - PLOGI
642 	 * - PRLI
643 	 * - RTV
644 	 *
645 	 * STATUS: OPTIONAL
646 	 */
647 	int (*rport_login)(struct fc_rport_priv *);
648 
649 	/*
650 	 * Logoff, and remove the rport from the transport if
651 	 * it had been added. This will send a LOGO to the target.
652 	 *
653 	 * STATUS: OPTIONAL
654 	 */
655 	int (*rport_logoff)(struct fc_rport_priv *);
656 
657 	/*
658 	 * Recieve a request from a remote port.
659 	 *
660 	 * STATUS: OPTIONAL
661 	 */
662 	void (*rport_recv_req)(struct fc_seq *, struct fc_frame *,
663 			       struct fc_lport *);
664 
665 	/*
666 	 * lookup an rport by it's port ID.
667 	 *
668 	 * STATUS: OPTIONAL
669 	 */
670 	struct fc_rport_priv *(*rport_lookup)(const struct fc_lport *, u32);
671 
672 	/*
673 	 * Destroy an rport after final kref_put().
674 	 * The argument is a pointer to the kref inside the fc_rport_priv.
675 	 */
676 	void (*rport_destroy)(struct kref *);
677 
678 	/*
679 	 * Send a fcp cmd from fsp pkt.
680 	 * Called with the SCSI host lock unlocked and irqs disabled.
681 	 *
682 	 * The resp handler is called when FCP_RSP received.
683 	 *
684 	 * STATUS: OPTIONAL
685 	 */
686 	int (*fcp_cmd_send)(struct fc_lport *, struct fc_fcp_pkt *,
687 			    void (*resp)(struct fc_seq *, struct fc_frame *,
688 					 void *));
689 
690 	/*
691 	 * Cleanup the FCP layer, used durring link down and reset
692 	 *
693 	 * STATUS: OPTIONAL
694 	 */
695 	void (*fcp_cleanup)(struct fc_lport *);
696 
697 	/*
698 	 * Abort all I/O on a local port
699 	 *
700 	 * STATUS: OPTIONAL
701 	 */
702 	void (*fcp_abort_io)(struct fc_lport *);
703 
704 	/*
705 	 * Receive a request for the discovery layer.
706 	 *
707 	 * STATUS: OPTIONAL
708 	 */
709 	void (*disc_recv_req)(struct fc_seq *, struct fc_frame *,
710 			      struct fc_lport *);
711 
712 	/*
713 	 * Start discovery for a local port.
714 	 *
715 	 * STATUS: OPTIONAL
716 	 */
717 	void (*disc_start)(void (*disc_callback)(struct fc_lport *,
718 						 enum fc_disc_event),
719 			   struct fc_lport *);
720 
721 	/*
722 	 * Stop discovery for a given lport. This will remove
723 	 * all discovered rports
724 	 *
725 	 * STATUS: OPTIONAL
726 	 */
727 	void (*disc_stop) (struct fc_lport *);
728 
729 	/*
730 	 * Stop discovery for a given lport. This will block
731 	 * until all discovered rports are deleted from the
732 	 * FC transport class
733 	 *
734 	 * STATUS: OPTIONAL
735 	 */
736 	void (*disc_stop_final) (struct fc_lport *);
737 };
738 
739 /**
740  * struct fc_disc - Discovery context
741  * @retry_count:   Number of retries
742  * @pending:       1 if discovery is pending, 0 if not
743  * @requesting:    1 if discovery has been requested, 0 if not
744  * @seq_count:     Number of sequences used for discovery
745  * @buf_len:       Length of the discovery buffer
746  * @disc_id:       Discovery ID
747  * @rports:        List of discovered remote ports
748  * @priv:          Private pointer for use by discovery code
749  * @disc_mutex:    Mutex that protects the discovery context
750  * @partial_buf:   Partial name buffer (if names are returned
751  *                 in multiple frames)
752  * @disc_work:     handle for delayed work context
753  * @disc_callback: Callback routine called when discovery completes
754  */
755 struct fc_disc {
756 	unsigned char         retry_count;
757 	unsigned char         pending;
758 	unsigned char         requested;
759 	unsigned short        seq_count;
760 	unsigned char         buf_len;
761 	u16                   disc_id;
762 
763 	struct list_head      rports;
764 	void		      *priv;
765 	struct mutex	      disc_mutex;
766 	struct fc_gpn_ft_resp partial_buf;
767 	struct delayed_work   disc_work;
768 
769 	void (*disc_callback)(struct fc_lport *,
770 			      enum fc_disc_event);
771 };
772 
773 /**
774  * struct fc_lport - Local port
775  * @host:                  The SCSI host associated with a local port
776  * @ema_list:              Exchange manager anchor list
777  * @dns_rdata:             The directory server remote port
778  * @ptp_rdata:             Point to point remote port
779  * @scsi_priv:             FCP layer internal data
780  * @disc:                  Discovery context
781  * @vports:                Child vports if N_Port
782  * @vport:                 Parent vport if VN_Port
783  * @tt:                    Libfc function template
784  * @link_up:               Link state (1 = link up, 0 = link down)
785  * @qfull:                 Queue state (1 queue is full, 0 queue is not full)
786  * @state:                 Identifies the state
787  * @boot_time:             Timestamp indicating when the local port came online
788  * @host_stats:            SCSI host statistics
789  * @dev_stats:             FCoE device stats (TODO: libfc should not be
790  *                         FCoE aware)
791  * @retry_count:           Number of retries in the current state
792  * @port_id:               FC Port ID
793  * @wwpn:                  World Wide Port Name
794  * @wwnn:                  World Wide Node Name
795  * @service_params:        Common service parameters
796  * @e_d_tov:               Error detection timeout value
797  * @r_a_tov:               Resouce allocation timeout value
798  * @rnid_gen:              RNID information
799  * @sg_supp:               Indicates if scatter gather is supported
800  * @seq_offload:           Indicates if sequence offload is supported
801  * @crc_offload:           Indicates if CRC offload is supported
802  * @lro_enabled:           Indicates if large receive offload is supported
803  * @does_npiv:             Supports multiple vports
804  * @npiv_enabled:          Switch/fabric allows NPIV
805  * @mfs:                   The maximum Fibre Channel payload size
806  * @max_retry_count:       The maximum retry attempts
807  * @max_rport_retry_count: The maximum remote port retry attempts
808  * @rport_priv_size:       Size needed by driver after struct fc_rport_priv
809  * @lro_xid:               The maximum XID for LRO
810  * @lso_max:               The maximum large offload send size
811  * @fcts:                  FC-4 type mask
812  * @lp_mutex:              Mutex to protect the local port
813  * @list:                  Handle for list of local ports
814  * @retry_work:            Handle to local port for delayed retry context
815  */
816 struct fc_lport {
817 	/* Associations */
818 	struct Scsi_Host	       *host;
819 	struct list_head	       ema_list;
820 	struct fc_rport_priv	       *dns_rdata;
821 	struct fc_rport_priv	       *ptp_rdata;
822 	void			       *scsi_priv;
823 	struct fc_disc                 disc;
824 
825 	/* Virtual port information */
826 	struct list_head	       vports;
827 	struct fc_vport		       *vport;
828 
829 	/* Operational Information */
830 	struct libfc_function_template tt;
831 	u8			       link_up;
832 	u8			       qfull;
833 	enum fc_lport_state	       state;
834 	unsigned long		       boot_time;
835 	struct fc_host_statistics      host_stats;
836 	struct fcoe_dev_stats	       *dev_stats;
837 	u8			       retry_count;
838 
839 	/* Fabric information */
840 	u32                            port_id;
841 	u64			       wwpn;
842 	u64			       wwnn;
843 	unsigned int		       service_params;
844 	unsigned int		       e_d_tov;
845 	unsigned int		       r_a_tov;
846 	struct fc_els_rnid_gen	       rnid_gen;
847 
848 	/* Capabilities */
849 	u32			       sg_supp:1;
850 	u32			       seq_offload:1;
851 	u32			       crc_offload:1;
852 	u32			       lro_enabled:1;
853 	u32			       does_npiv:1;
854 	u32			       npiv_enabled:1;
855 	u32			       point_to_multipoint:1;
856 	u32			       mfs;
857 	u8			       max_retry_count;
858 	u8			       max_rport_retry_count;
859 	u16			       rport_priv_size;
860 	u16			       link_speed;
861 	u16			       link_supported_speeds;
862 	u16			       lro_xid;
863 	unsigned int		       lso_max;
864 	struct fc_ns_fts	       fcts;
865 
866 	/* Miscellaneous */
867 	struct mutex                   lp_mutex;
868 	struct list_head               list;
869 	struct delayed_work	       retry_work;
870 };
871 
872 /*
873  * FC_LPORT HELPER FUNCTIONS
874  *****************************/
875 
876 /**
877  * fc_lport_test_ready() - Determine if a local port is in the READY state
878  * @lport: The local port to test
879  */
880 static inline int fc_lport_test_ready(struct fc_lport *lport)
881 {
882 	return lport->state == LPORT_ST_READY;
883 }
884 
885 /**
886  * fc_set_wwnn() - Set the World Wide Node Name of a local port
887  * @lport: The local port whose WWNN is to be set
888  * @wwnn:  The new WWNN
889  */
890 static inline void fc_set_wwnn(struct fc_lport *lport, u64 wwnn)
891 {
892 	lport->wwnn = wwnn;
893 }
894 
895 /**
896  * fc_set_wwpn() - Set the World Wide Port Name of a local port
897  * @lport: The local port whose WWPN is to be set
898  * @wwnn:  The new WWPN
899  */
900 static inline void fc_set_wwpn(struct fc_lport *lport, u64 wwnn)
901 {
902 	lport->wwpn = wwnn;
903 }
904 
905 /**
906  * fc_lport_state_enter() - Change a local port's state
907  * @lport: The local port whose state is to change
908  * @state: The new state
909  */
910 static inline void fc_lport_state_enter(struct fc_lport *lport,
911 					enum fc_lport_state state)
912 {
913 	if (state != lport->state)
914 		lport->retry_count = 0;
915 	lport->state = state;
916 }
917 
918 /**
919  * fc_lport_init_stats() - Allocate per-CPU statistics for a local port
920  * @lport: The local port whose statistics are to be initialized
921  */
922 static inline int fc_lport_init_stats(struct fc_lport *lport)
923 {
924 	lport->dev_stats = alloc_percpu(struct fcoe_dev_stats);
925 	if (!lport->dev_stats)
926 		return -ENOMEM;
927 	return 0;
928 }
929 
930 /**
931  * fc_lport_free_stats() - Free memory for a local port's statistics
932  * @lport: The local port whose statistics are to be freed
933  */
934 static inline void fc_lport_free_stats(struct fc_lport *lport)
935 {
936 	free_percpu(lport->dev_stats);
937 }
938 
939 /**
940  * lport_priv() - Return the private data from a local port
941  * @lport: The local port whose private data is to be retreived
942  */
943 static inline void *lport_priv(const struct fc_lport *lport)
944 {
945 	return (void *)(lport + 1);
946 }
947 
948 /**
949  * libfc_host_alloc() - Allocate a Scsi_Host with room for a local port and
950  *                      LLD private data
951  * @sht:       The SCSI host template
952  * @priv_size: Size of private data
953  *
954  * Returns: libfc lport
955  */
956 static inline struct fc_lport *
957 libfc_host_alloc(struct scsi_host_template *sht, int priv_size)
958 {
959 	struct fc_lport *lport;
960 	struct Scsi_Host *shost;
961 
962 	shost = scsi_host_alloc(sht, sizeof(*lport) + priv_size);
963 	if (!shost)
964 		return NULL;
965 	lport = shost_priv(shost);
966 	lport->host = shost;
967 	INIT_LIST_HEAD(&lport->ema_list);
968 	INIT_LIST_HEAD(&lport->vports);
969 	return lport;
970 }
971 
972 /*
973  * FC_FCP HELPER FUNCTIONS
974  *****************************/
975 static inline bool fc_fcp_is_read(const struct fc_fcp_pkt *fsp)
976 {
977 	if (fsp && fsp->cmd)
978 		return fsp->cmd->sc_data_direction == DMA_FROM_DEVICE;
979 	return false;
980 }
981 
982 /*
983  * LOCAL PORT LAYER
984  *****************************/
985 int fc_lport_init(struct fc_lport *);
986 int fc_lport_destroy(struct fc_lport *);
987 int fc_fabric_logoff(struct fc_lport *);
988 int fc_fabric_login(struct fc_lport *);
989 void __fc_linkup(struct fc_lport *);
990 void fc_linkup(struct fc_lport *);
991 void __fc_linkdown(struct fc_lport *);
992 void fc_linkdown(struct fc_lport *);
993 void fc_vport_setlink(struct fc_lport *);
994 void fc_vports_linkchange(struct fc_lport *);
995 int fc_lport_config(struct fc_lport *);
996 int fc_lport_reset(struct fc_lport *);
997 int fc_set_mfs(struct fc_lport *, u32 mfs);
998 struct fc_lport *libfc_vport_create(struct fc_vport *, int privsize);
999 struct fc_lport *fc_vport_id_lookup(struct fc_lport *, u32 port_id);
1000 int fc_lport_bsg_request(struct fc_bsg_job *);
1001 void fc_lport_set_local_id(struct fc_lport *, u32 port_id);
1002 
1003 /*
1004  * REMOTE PORT LAYER
1005  *****************************/
1006 int fc_rport_init(struct fc_lport *);
1007 void fc_rport_terminate_io(struct fc_rport *);
1008 
1009 /*
1010  * DISCOVERY LAYER
1011  *****************************/
1012 int fc_disc_init(struct fc_lport *);
1013 
1014 static inline struct fc_lport *fc_disc_lport(struct fc_disc *disc)
1015 {
1016 	return container_of(disc, struct fc_lport, disc);
1017 }
1018 
1019 /*
1020  * FCP LAYER
1021  *****************************/
1022 int fc_fcp_init(struct fc_lport *);
1023 void fc_fcp_destroy(struct fc_lport *);
1024 
1025 /*
1026  * SCSI INTERACTION LAYER
1027  *****************************/
1028 int fc_queuecommand(struct scsi_cmnd *,
1029 		    void (*done)(struct scsi_cmnd *));
1030 int fc_eh_abort(struct scsi_cmnd *);
1031 int fc_eh_device_reset(struct scsi_cmnd *);
1032 int fc_eh_host_reset(struct scsi_cmnd *);
1033 int fc_slave_alloc(struct scsi_device *);
1034 int fc_change_queue_depth(struct scsi_device *, int qdepth, int reason);
1035 int fc_change_queue_type(struct scsi_device *, int tag_type);
1036 
1037 /*
1038  * ELS/CT interface
1039  *****************************/
1040 int fc_elsct_init(struct fc_lport *);
1041 struct fc_seq *fc_elsct_send(struct fc_lport *, u32 did,
1042 				    struct fc_frame *,
1043 				    unsigned int op,
1044 				    void (*resp)(struct fc_seq *,
1045 						 struct fc_frame *,
1046 						 void *arg),
1047 				    void *arg, u32 timer_msec);
1048 void fc_lport_flogi_resp(struct fc_seq *, struct fc_frame *, void *);
1049 void fc_lport_logo_resp(struct fc_seq *, struct fc_frame *, void *);
1050 
1051 
1052 /*
1053  * EXCHANGE MANAGER LAYER
1054  *****************************/
1055 int fc_exch_init(struct fc_lport *);
1056 struct fc_exch_mgr_anchor *fc_exch_mgr_add(struct fc_lport *,
1057 					   struct fc_exch_mgr *,
1058 					   bool (*match)(struct fc_frame *));
1059 void fc_exch_mgr_del(struct fc_exch_mgr_anchor *);
1060 int fc_exch_mgr_list_clone(struct fc_lport *src, struct fc_lport *dst);
1061 struct fc_exch_mgr *fc_exch_mgr_alloc(struct fc_lport *, enum fc_class class,
1062 				      u16 min_xid, u16 max_xid,
1063 				      bool (*match)(struct fc_frame *));
1064 void fc_exch_mgr_free(struct fc_lport *);
1065 void fc_exch_recv(struct fc_lport *, struct fc_frame *);
1066 void fc_exch_mgr_reset(struct fc_lport *, u32 s_id, u32 d_id);
1067 
1068 /*
1069  * Functions for fc_functions_template
1070  */
1071 void fc_get_host_speed(struct Scsi_Host *);
1072 void fc_get_host_port_state(struct Scsi_Host *);
1073 void fc_set_rport_loss_tmo(struct fc_rport *, u32 timeout);
1074 struct fc_host_statistics *fc_get_host_stats(struct Scsi_Host *);
1075 
1076 #endif /* _LIBFC_H_ */
1077