xref: /openbmc/linux/include/scsi/libfc.h (revision fd589a8f)
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 
30 #include <scsi/fc/fc_fcp.h>
31 #include <scsi/fc/fc_ns.h>
32 #include <scsi/fc/fc_els.h>
33 #include <scsi/fc/fc_gs.h>
34 
35 #include <scsi/fc_frame.h>
36 
37 #define FC_LIBFC_LOGGING 0x01 /* General logging, not categorized */
38 #define FC_LPORT_LOGGING 0x02 /* lport layer logging */
39 #define FC_DISC_LOGGING  0x04 /* discovery layer logging */
40 #define FC_RPORT_LOGGING 0x08 /* rport layer logging */
41 #define FC_FCP_LOGGING   0x10 /* I/O path logging */
42 #define FC_EM_LOGGING    0x20 /* Exchange Manager logging */
43 #define FC_EXCH_LOGGING  0x40 /* Exchange/Sequence logging */
44 #define FC_SCSI_LOGGING  0x80 /* SCSI logging (mostly error handling) */
45 
46 extern unsigned int fc_debug_logging;
47 
48 #define FC_CHECK_LOGGING(LEVEL, CMD)				\
49 do {								\
50 	if (unlikely(fc_debug_logging & LEVEL))			\
51 		do {						\
52 			CMD;					\
53 		} while (0);					\
54 } while (0)
55 
56 #define FC_LIBFC_DBG(fmt, args...)					\
57 	FC_CHECK_LOGGING(FC_LIBFC_LOGGING,				\
58 			 printk(KERN_INFO "libfc: " fmt, ##args))
59 
60 #define FC_LPORT_DBG(lport, fmt, args...)				\
61 	FC_CHECK_LOGGING(FC_LPORT_LOGGING,				\
62 			 printk(KERN_INFO "host%u: lport %6x: " fmt,	\
63 				(lport)->host->host_no,			\
64 				fc_host_port_id((lport)->host), ##args))
65 
66 #define FC_DISC_DBG(disc, fmt, args...)					\
67 	FC_CHECK_LOGGING(FC_DISC_LOGGING,				\
68 			 printk(KERN_INFO "host%u: disc: " fmt,		\
69 				(disc)->lport->host->host_no,		\
70 				##args))
71 
72 #define FC_RPORT_ID_DBG(lport, port_id, fmt, args...)			\
73 	FC_CHECK_LOGGING(FC_RPORT_LOGGING,				\
74 			 printk(KERN_INFO "host%u: rport %6x: " fmt,	\
75 				(lport)->host->host_no,			\
76 				(port_id), ##args))
77 
78 #define FC_RPORT_DBG(rdata, fmt, args...)				\
79 	FC_RPORT_ID_DBG((rdata)->local_port, (rdata)->ids.port_id, fmt, ##args)
80 
81 #define FC_FCP_DBG(pkt, fmt, args...)					\
82 	FC_CHECK_LOGGING(FC_FCP_LOGGING,				\
83 			 printk(KERN_INFO "host%u: fcp: %6x: " fmt,	\
84 				(pkt)->lp->host->host_no,		\
85 				pkt->rport->port_id, ##args))
86 
87 #define FC_EXCH_DBG(exch, fmt, args...)					\
88 	FC_CHECK_LOGGING(FC_EXCH_LOGGING,				\
89 			 printk(KERN_INFO "host%u: xid %4x: " fmt,	\
90 				(exch)->lp->host->host_no,		\
91 				exch->xid, ##args))
92 
93 #define FC_SCSI_DBG(lport, fmt, args...)				\
94 	FC_CHECK_LOGGING(FC_SCSI_LOGGING,                               \
95 			 printk(KERN_INFO "host%u: scsi: " fmt,		\
96 				(lport)->host->host_no,	##args))
97 
98 /*
99  * libfc error codes
100  */
101 #define	FC_NO_ERR	0	/* no error */
102 #define	FC_EX_TIMEOUT	1	/* Exchange timeout */
103 #define	FC_EX_CLOSED	2	/* Exchange closed */
104 
105 /* some helpful macros */
106 
107 #define ntohll(x) be64_to_cpu(x)
108 #define htonll(x) cpu_to_be64(x)
109 
110 #define ntoh24(p) (((p)[0] << 16) | ((p)[1] << 8) | ((p)[2]))
111 
112 #define hton24(p, v)	do {			\
113 		p[0] = (((v) >> 16) & 0xFF);	\
114 		p[1] = (((v) >> 8) & 0xFF);	\
115 		p[2] = ((v) & 0xFF);		\
116 	} while (0)
117 
118 /*
119  * FC HBA status
120  */
121 enum fc_lport_state {
122 	LPORT_ST_DISABLED = 0,
123 	LPORT_ST_FLOGI,
124 	LPORT_ST_DNS,
125 	LPORT_ST_RPN_ID,
126 	LPORT_ST_RFT_ID,
127 	LPORT_ST_SCR,
128 	LPORT_ST_READY,
129 	LPORT_ST_LOGO,
130 	LPORT_ST_RESET
131 };
132 
133 enum fc_disc_event {
134 	DISC_EV_NONE = 0,
135 	DISC_EV_SUCCESS,
136 	DISC_EV_FAILED
137 };
138 
139 enum fc_rport_state {
140 	RPORT_ST_INIT,		/* initialized */
141 	RPORT_ST_PLOGI,		/* waiting for PLOGI completion */
142 	RPORT_ST_PRLI,		/* waiting for PRLI completion */
143 	RPORT_ST_RTV,		/* waiting for RTV completion */
144 	RPORT_ST_READY,		/* ready for use */
145 	RPORT_ST_LOGO,		/* port logout sent */
146 	RPORT_ST_ADISC,		/* Discover Address sent */
147 	RPORT_ST_DELETE,	/* port being deleted */
148 };
149 
150 /**
151  * struct fc_disc_port - temporary discovery port to hold rport identifiers
152  * @lp:         Fibre Channel host port instance
153  * @peers:      Node for list management during discovery and RSCN processing
154  * @rport_work: Work struct for starting the rport state machine
155  * @port_id:    Port ID of the discovered port
156  */
157 struct fc_disc_port {
158 	struct fc_lport             *lp;
159 	struct list_head            peers;
160 	struct work_struct	    rport_work;
161 	u32                         port_id;
162 };
163 
164 enum fc_rport_event {
165 	RPORT_EV_NONE = 0,
166 	RPORT_EV_READY,
167 	RPORT_EV_FAILED,
168 	RPORT_EV_STOP,
169 	RPORT_EV_LOGO
170 };
171 
172 struct fc_rport_priv;
173 
174 struct fc_rport_operations {
175 	void (*event_callback)(struct fc_lport *, struct fc_rport_priv *,
176 			       enum fc_rport_event);
177 };
178 
179 /**
180  * struct fc_rport_libfc_priv - libfc internal information about a remote port
181  * @local_port: Fibre Channel host port instance
182  * @rp_state: indicates READY for I/O or DELETE when blocked.
183  * @flags: REC and RETRY supported flags
184  * @e_d_tov: error detect timeout value (in msec)
185  * @r_a_tov: resource allocation timeout value (in msec)
186  */
187 struct fc_rport_libfc_priv {
188 	struct fc_lport		   *local_port;
189 	enum fc_rport_state        rp_state;
190 	u16			   flags;
191 	#define FC_RP_FLAGS_REC_SUPPORTED	(1 << 0)
192 	#define FC_RP_FLAGS_RETRY		(1 << 1)
193 	unsigned int	           e_d_tov;
194 	unsigned int	           r_a_tov;
195 };
196 
197 /**
198  * struct fc_rport_priv - libfc rport and discovery info about a remote port
199  * @local_port: Fibre Channel host port instance
200  * @rport: transport remote port
201  * @kref: reference counter
202  * @rp_state: state tracks progress of PLOGI, PRLI, and RTV exchanges
203  * @ids: remote port identifiers and roles
204  * @flags: REC and RETRY supported flags
205  * @max_seq: maximum number of concurrent sequences
206  * @disc_id: discovery identifier
207  * @maxframe_size: maximum frame size
208  * @retries: retry count in current state
209  * @e_d_tov: error detect timeout value (in msec)
210  * @r_a_tov: resource allocation timeout value (in msec)
211  * @rp_mutex: mutex protects rport
212  * @retry_work:
213  * @event_callback: Callback for rport READY, FAILED or LOGO
214  */
215 struct fc_rport_priv {
216 	struct fc_lport		   *local_port;
217 	struct fc_rport		   *rport;
218 	struct kref		   kref;
219 	enum fc_rport_state        rp_state;
220 	struct fc_rport_identifiers ids;
221 	u16			   flags;
222 	u16		           max_seq;
223 	u16			   disc_id;
224 	u16			   maxframe_size;
225 	unsigned int	           retries;
226 	unsigned int	           e_d_tov;
227 	unsigned int	           r_a_tov;
228 	struct mutex               rp_mutex;
229 	struct delayed_work	   retry_work;
230 	enum fc_rport_event        event;
231 	struct fc_rport_operations *ops;
232 	struct list_head           peers;
233 	struct work_struct         event_work;
234 	u32			   supported_classes;
235 };
236 
237 /*
238  * fcoe stats structure
239  */
240 struct fcoe_dev_stats {
241 	u64		SecondsSinceLastReset;
242 	u64		TxFrames;
243 	u64		TxWords;
244 	u64		RxFrames;
245 	u64		RxWords;
246 	u64		ErrorFrames;
247 	u64		DumpedFrames;
248 	u64		LinkFailureCount;
249 	u64		LossOfSignalCount;
250 	u64		InvalidTxWordCount;
251 	u64		InvalidCRCCount;
252 	u64		InputRequests;
253 	u64		OutputRequests;
254 	u64		ControlRequests;
255 	u64		InputMegabytes;
256 	u64		OutputMegabytes;
257 };
258 
259 /*
260  * els data is used for passing ELS respone specific
261  * data to send ELS response mainly using infomation
262  * in exchange and sequence in EM layer.
263  */
264 struct fc_seq_els_data {
265 	struct fc_frame *fp;
266 	enum fc_els_rjt_reason reason;
267 	enum fc_els_rjt_explan explan;
268 };
269 
270 /*
271  * FCP request structure, one for each scsi cmd request
272  */
273 struct fc_fcp_pkt {
274 	/*
275 	 * housekeeping stuff
276 	 */
277 	struct fc_lport *lp;	/* handle to hba struct */
278 	u16		state;		/* scsi_pkt state state */
279 	u16		tgt_flags;	/* target flags	 */
280 	atomic_t	ref_cnt;	/* fcp pkt ref count */
281 	spinlock_t	scsi_pkt_lock;	/* Must be taken before the host lock
282 					 * if both are held at the same time */
283 	/*
284 	 * SCSI I/O related stuff
285 	 */
286 	struct scsi_cmnd *cmd;		/* scsi command pointer. set/clear
287 					 * under host lock */
288 	struct list_head list;		/* tracks queued commands. access under
289 					 * host lock */
290 	/*
291 	 * timeout related stuff
292 	 */
293 	struct timer_list timer;	/* command timer */
294 	struct completion tm_done;
295 	int	wait_for_comp;
296 	unsigned long	start_time;	/* start jiffie */
297 	unsigned long	end_time;	/* end jiffie */
298 	unsigned long	last_pkt_time;	 /* jiffies of last frame received */
299 
300 	/*
301 	 * scsi cmd and data transfer information
302 	 */
303 	u32		data_len;
304 	/*
305 	 * transport related veriables
306 	 */
307 	struct fcp_cmnd cdb_cmd;
308 	size_t		xfer_len;
309 	u16		xfer_ddp;	/* this xfer is ddped */
310 	u32		xfer_contig_end; /* offset of end of contiguous xfer */
311 	u16		max_payload;	/* max payload size in bytes */
312 
313 	/*
314 	 * scsi/fcp return status
315 	 */
316 	u32		io_status;	/* SCSI result upper 24 bits */
317 	u8		cdb_status;
318 	u8		status_code;	/* FCP I/O status */
319 	/* bit 3 Underrun bit 2: overrun */
320 	u8		scsi_comp_flags;
321 	u32		req_flags;	/* bit 0: read bit:1 write */
322 	u32		scsi_resid;	/* residule length */
323 
324 	struct fc_rport	*rport;		/* remote port pointer */
325 	struct fc_seq	*seq_ptr;	/* current sequence pointer */
326 	/*
327 	 * Error Processing
328 	 */
329 	u8		recov_retry;	/* count of recovery retries */
330 	struct fc_seq	*recov_seq;	/* sequence for REC or SRR */
331 };
332 /*
333  * FC_FCP HELPER FUNCTIONS
334  *****************************/
335 static inline bool fc_fcp_is_read(const struct fc_fcp_pkt *fsp)
336 {
337 	if (fsp && fsp->cmd)
338 		return fsp->cmd->sc_data_direction == DMA_FROM_DEVICE;
339 	return false;
340 }
341 
342 /*
343  * Structure and function definitions for managing Fibre Channel Exchanges
344  * and Sequences
345  *
346  * fc_exch holds state for one exchange and links to its active sequence.
347  *
348  * fc_seq holds the state for an individual sequence.
349  */
350 
351 struct fc_exch_mgr;
352 struct fc_exch_mgr_anchor;
353 extern u16	fc_cpu_mask;	/* cpu mask for possible cpus */
354 
355 /*
356  * Sequence.
357  */
358 struct fc_seq {
359 	u8	id;		/* seq ID */
360 	u16	ssb_stat;	/* status flags for sequence status block */
361 	u16	cnt;		/* frames sent so far on sequence */
362 	u32	rec_data;	/* FC-4 value for REC */
363 };
364 
365 #define FC_EX_DONE		(1 << 0) /* ep is completed */
366 #define FC_EX_RST_CLEANUP	(1 << 1) /* reset is forcing completion */
367 
368 /*
369  * Exchange.
370  *
371  * Locking notes: The ex_lock protects following items:
372  *	state, esb_stat, f_ctl, seq.ssb_stat
373  *	seq_id
374  *	sequence allocation
375  */
376 struct fc_exch {
377 	struct fc_exch_mgr *em;		/* exchange manager */
378 	struct fc_exch_pool *pool;	/* per cpu exches pool */
379 	u32		state;		/* internal driver state */
380 	u16		xid;		/* our exchange ID */
381 	struct list_head	ex_list;	/* free or busy list linkage */
382 	spinlock_t	ex_lock;	/* lock covering exchange state */
383 	atomic_t	ex_refcnt;	/* reference counter */
384 	struct delayed_work timeout_work; /* timer for upper level protocols */
385 	struct fc_lport	*lp;		/* fc device instance */
386 	u16		oxid;		/* originator's exchange ID */
387 	u16		rxid;		/* responder's exchange ID */
388 	u32		oid;		/* originator's FCID */
389 	u32		sid;		/* source FCID */
390 	u32		did;		/* destination FCID */
391 	u32		esb_stat;	/* exchange status for ESB */
392 	u32		r_a_tov;	/* r_a_tov from rport (msec) */
393 	u8		seq_id;		/* next sequence ID to use */
394 	u32		f_ctl;		/* F_CTL flags for sequences */
395 	u8		fh_type;	/* frame type */
396 	enum fc_class	class;		/* class of service */
397 	struct fc_seq	seq;		/* single sequence */
398 	/*
399 	 * Handler for responses to this current exchange.
400 	 */
401 	void		(*resp)(struct fc_seq *, struct fc_frame *, void *);
402 	void		(*destructor)(struct fc_seq *, void *);
403 	/*
404 	 * arg is passed as void pointer to exchange
405 	 * resp and destructor handlers
406 	 */
407 	void		*arg;
408 };
409 #define	fc_seq_exch(sp) container_of(sp, struct fc_exch, seq)
410 
411 struct libfc_function_template {
412 
413 	/*
414 	 * Interface to send a FC frame
415 	 *
416 	 * STATUS: REQUIRED
417 	 */
418 	int (*frame_send)(struct fc_lport *lp, struct fc_frame *fp);
419 
420 	/*
421 	 * Interface to send ELS/CT frames
422 	 *
423 	 * STATUS: OPTIONAL
424 	 */
425 	struct fc_seq *(*elsct_send)(struct fc_lport *lport,
426 				     u32 did,
427 				     struct fc_frame *fp,
428 				     unsigned int op,
429 				     void (*resp)(struct fc_seq *,
430 					     struct fc_frame *fp,
431 					     void *arg),
432 				     void *arg, u32 timer_msec);
433 
434 	/*
435 	 * Send the FC frame payload using a new exchange and sequence.
436 	 *
437 	 * The frame pointer with some of the header's fields must be
438 	 * filled before calling exch_seq_send(), those fields are,
439 	 *
440 	 * - routing control
441 	 * - FC port did
442 	 * - FC port sid
443 	 * - FC header type
444 	 * - frame control
445 	 * - parameter or relative offset
446 	 *
447 	 * The exchange response handler is set in this routine to resp()
448 	 * function pointer. It can be called in two scenarios: if a timeout
449 	 * occurs or if a response frame is received for the exchange. The
450 	 * fc_frame pointer in response handler will also indicate timeout
451 	 * as error using IS_ERR related macros.
452 	 *
453 	 * The exchange destructor handler is also set in this routine.
454 	 * The destructor handler is invoked by EM layer when exchange
455 	 * is about to free, this can be used by caller to free its
456 	 * resources along with exchange free.
457 	 *
458 	 * The arg is passed back to resp and destructor handler.
459 	 *
460 	 * The timeout value (in msec) for an exchange is set if non zero
461 	 * timer_msec argument is specified. The timer is canceled when
462 	 * it fires or when the exchange is done. The exchange timeout handler
463 	 * is registered by EM layer.
464 	 *
465 	 * STATUS: OPTIONAL
466 	 */
467 	struct fc_seq *(*exch_seq_send)(struct fc_lport *lp,
468 					struct fc_frame *fp,
469 					void (*resp)(struct fc_seq *sp,
470 						     struct fc_frame *fp,
471 						     void *arg),
472 					void (*destructor)(struct fc_seq *sp,
473 							   void *arg),
474 					void *arg, unsigned int timer_msec);
475 
476 	/*
477 	 * Sets up the DDP context for a given exchange id on the given
478 	 * scatterlist if LLD supports DDP for large receive.
479 	 *
480 	 * STATUS: OPTIONAL
481 	 */
482 	int (*ddp_setup)(struct fc_lport *lp, u16 xid,
483 			 struct scatterlist *sgl, unsigned int sgc);
484 	/*
485 	 * Completes the DDP transfer and returns the length of data DDPed
486 	 * for the given exchange id.
487 	 *
488 	 * STATUS: OPTIONAL
489 	 */
490 	int (*ddp_done)(struct fc_lport *lp, u16 xid);
491 	/*
492 	 * Send a frame using an existing sequence and exchange.
493 	 *
494 	 * STATUS: OPTIONAL
495 	 */
496 	int (*seq_send)(struct fc_lport *lp, struct fc_seq *sp,
497 			struct fc_frame *fp);
498 
499 	/*
500 	 * Send an ELS response using infomation from a previous
501 	 * exchange and sequence.
502 	 *
503 	 * STATUS: OPTIONAL
504 	 */
505 	void (*seq_els_rsp_send)(struct fc_seq *sp, enum fc_els_cmd els_cmd,
506 				 struct fc_seq_els_data *els_data);
507 
508 	/*
509 	 * Abort an exchange and sequence. Generally called because of a
510 	 * exchange timeout or an abort from the upper layer.
511 	 *
512 	 * A timer_msec can be specified for abort timeout, if non-zero
513 	 * timer_msec value is specified then exchange resp handler
514 	 * will be called with timeout error if no response to abort.
515 	 *
516 	 * STATUS: OPTIONAL
517 	 */
518 	int (*seq_exch_abort)(const struct fc_seq *req_sp,
519 			      unsigned int timer_msec);
520 
521 	/*
522 	 * Indicate that an exchange/sequence tuple is complete and the memory
523 	 * allocated for the related objects may be freed.
524 	 *
525 	 * STATUS: OPTIONAL
526 	 */
527 	void (*exch_done)(struct fc_seq *sp);
528 
529 	/*
530 	 * Start a new sequence on the same exchange/sequence tuple.
531 	 *
532 	 * STATUS: OPTIONAL
533 	 */
534 	struct fc_seq *(*seq_start_next)(struct fc_seq *sp);
535 
536 	/*
537 	 * Reset an exchange manager, completing all sequences and exchanges.
538 	 * If s_id is non-zero, reset only exchanges originating from that FID.
539 	 * If d_id is non-zero, reset only exchanges sending to that FID.
540 	 *
541 	 * STATUS: OPTIONAL
542 	 */
543 	void (*exch_mgr_reset)(struct fc_lport *,
544 			       u32 s_id, u32 d_id);
545 
546 	/*
547 	 * Flush the rport work queue. Generally used before shutdown.
548 	 *
549 	 * STATUS: OPTIONAL
550 	 */
551 	void (*rport_flush_queue)(void);
552 
553 	/*
554 	 * Receive a frame for a local port.
555 	 *
556 	 * STATUS: OPTIONAL
557 	 */
558 	void (*lport_recv)(struct fc_lport *lp, struct fc_seq *sp,
559 			   struct fc_frame *fp);
560 
561 	/*
562 	 * Reset the local port.
563 	 *
564 	 * STATUS: OPTIONAL
565 	 */
566 	int (*lport_reset)(struct fc_lport *);
567 
568 	/*
569 	 * Create a remote port with a given port ID
570 	 *
571 	 * STATUS: OPTIONAL
572 	 */
573 	struct fc_rport_priv *(*rport_create)(struct fc_lport *, u32);
574 
575 	/*
576 	 * Initiates the RP state machine. It is called from the LP module.
577 	 * This function will issue the following commands to the N_Port
578 	 * identified by the FC ID provided.
579 	 *
580 	 * - PLOGI
581 	 * - PRLI
582 	 * - RTV
583 	 *
584 	 * STATUS: OPTIONAL
585 	 */
586 	int (*rport_login)(struct fc_rport_priv *);
587 
588 	/*
589 	 * Logoff, and remove the rport from the transport if
590 	 * it had been added. This will send a LOGO to the target.
591 	 *
592 	 * STATUS: OPTIONAL
593 	 */
594 	int (*rport_logoff)(struct fc_rport_priv *);
595 
596 	/*
597 	 * Recieve a request from a remote port.
598 	 *
599 	 * STATUS: OPTIONAL
600 	 */
601 	void (*rport_recv_req)(struct fc_seq *, struct fc_frame *,
602 			       struct fc_lport *);
603 
604 	/*
605 	 * lookup an rport by it's port ID.
606 	 *
607 	 * STATUS: OPTIONAL
608 	 */
609 	struct fc_rport_priv *(*rport_lookup)(const struct fc_lport *, u32);
610 
611 	/*
612 	 * Destroy an rport after final kref_put().
613 	 * The argument is a pointer to the kref inside the fc_rport_priv.
614 	 */
615 	void (*rport_destroy)(struct kref *);
616 
617 	/*
618 	 * Send a fcp cmd from fsp pkt.
619 	 * Called with the SCSI host lock unlocked and irqs disabled.
620 	 *
621 	 * The resp handler is called when FCP_RSP received.
622 	 *
623 	 * STATUS: OPTIONAL
624 	 */
625 	int (*fcp_cmd_send)(struct fc_lport *lp, struct fc_fcp_pkt *fsp,
626 			    void (*resp)(struct fc_seq *, struct fc_frame *fp,
627 					 void *arg));
628 
629 	/*
630 	 * Cleanup the FCP layer, used durring link down and reset
631 	 *
632 	 * STATUS: OPTIONAL
633 	 */
634 	void (*fcp_cleanup)(struct fc_lport *lp);
635 
636 	/*
637 	 * Abort all I/O on a local port
638 	 *
639 	 * STATUS: OPTIONAL
640 	 */
641 	void (*fcp_abort_io)(struct fc_lport *lp);
642 
643 	/*
644 	 * Receive a request for the discovery layer.
645 	 *
646 	 * STATUS: OPTIONAL
647 	 */
648 	void (*disc_recv_req)(struct fc_seq *,
649 			      struct fc_frame *, struct fc_lport *);
650 
651 	/*
652 	 * Start discovery for a local port.
653 	 *
654 	 * STATUS: OPTIONAL
655 	 */
656 	void (*disc_start)(void (*disc_callback)(struct fc_lport *,
657 						 enum fc_disc_event),
658 			   struct fc_lport *);
659 
660 	/*
661 	 * Stop discovery for a given lport. This will remove
662 	 * all discovered rports
663 	 *
664 	 * STATUS: OPTIONAL
665 	 */
666 	void (*disc_stop) (struct fc_lport *);
667 
668 	/*
669 	 * Stop discovery for a given lport. This will block
670 	 * until all discovered rports are deleted from the
671 	 * FC transport class
672 	 *
673 	 * STATUS: OPTIONAL
674 	 */
675 	void (*disc_stop_final) (struct fc_lport *);
676 };
677 
678 /* information used by the discovery layer */
679 struct fc_disc {
680 	unsigned char		retry_count;
681 	unsigned char		pending;
682 	unsigned char		requested;
683 	unsigned short		seq_count;
684 	unsigned char		buf_len;
685 	u16			disc_id;
686 
687 	void (*disc_callback)(struct fc_lport *,
688 			      enum fc_disc_event);
689 
690 	struct list_head	 rports;
691 	struct fc_lport		*lport;
692 	struct mutex		disc_mutex;
693 	struct fc_gpn_ft_resp	partial_buf;	/* partial name buffer */
694 	struct delayed_work	disc_work;
695 };
696 
697 struct fc_lport {
698 	struct list_head list;
699 
700 	/* Associations */
701 	struct Scsi_Host	*host;
702 	struct list_head	ema_list;
703 	struct fc_rport_priv	*dns_rp;
704 	struct fc_rport_priv	*ptp_rp;
705 	void			*scsi_priv;
706 	struct fc_disc          disc;
707 
708 	/* Operational Information */
709 	struct libfc_function_template tt;
710 	u8			link_up;
711 	u8			qfull;
712 	enum fc_lport_state	state;
713 	unsigned long		boot_time;
714 
715 	struct fc_host_statistics host_stats;
716 	struct fcoe_dev_stats	*dev_stats;
717 
718 	u64			wwpn;
719 	u64			wwnn;
720 	u8			retry_count;
721 
722 	/* Capabilities */
723 	u32			sg_supp:1;	/* scatter gather supported */
724 	u32			seq_offload:1;	/* seq offload supported */
725 	u32			crc_offload:1;	/* crc offload supported */
726 	u32			lro_enabled:1;	/* large receive offload */
727 	u32			mfs;	        /* max FC payload size */
728 	unsigned int		service_params;
729 	unsigned int		e_d_tov;
730 	unsigned int		r_a_tov;
731 	u8			max_retry_count;
732 	u8			max_rport_retry_count;
733 	u16			link_speed;
734 	u16			link_supported_speeds;
735 	u16			lro_xid;	/* max xid for fcoe lro */
736 	unsigned int		lso_max;	/* max large send size */
737 	struct fc_ns_fts	fcts;	        /* FC-4 type masks */
738 	struct fc_els_rnid_gen	rnid_gen;	/* RNID information */
739 
740 	/* Semaphores */
741 	struct mutex lp_mutex;
742 
743 	/* Miscellaneous */
744 	struct delayed_work	retry_work;
745 	struct delayed_work	disc_work;
746 };
747 
748 /*
749  * FC_LPORT HELPER FUNCTIONS
750  *****************************/
751 static inline int fc_lport_test_ready(struct fc_lport *lp)
752 {
753 	return lp->state == LPORT_ST_READY;
754 }
755 
756 static inline void fc_set_wwnn(struct fc_lport *lp, u64 wwnn)
757 {
758 	lp->wwnn = wwnn;
759 }
760 
761 static inline void fc_set_wwpn(struct fc_lport *lp, u64 wwnn)
762 {
763 	lp->wwpn = wwnn;
764 }
765 
766 static inline void fc_lport_state_enter(struct fc_lport *lp,
767 					enum fc_lport_state state)
768 {
769 	if (state != lp->state)
770 		lp->retry_count = 0;
771 	lp->state = state;
772 }
773 
774 static inline int fc_lport_init_stats(struct fc_lport *lp)
775 {
776 	/* allocate per cpu stats block */
777 	lp->dev_stats = alloc_percpu(struct fcoe_dev_stats);
778 	if (!lp->dev_stats)
779 		return -ENOMEM;
780 	return 0;
781 }
782 
783 static inline void fc_lport_free_stats(struct fc_lport *lp)
784 {
785 	free_percpu(lp->dev_stats);
786 }
787 
788 static inline struct fcoe_dev_stats *fc_lport_get_stats(struct fc_lport *lp)
789 {
790 	return per_cpu_ptr(lp->dev_stats, smp_processor_id());
791 }
792 
793 static inline void *lport_priv(const struct fc_lport *lp)
794 {
795 	return (void *)(lp + 1);
796 }
797 
798 /**
799  * libfc_host_alloc() - Allocate a Scsi_Host with room for the fc_lport
800  * @sht: ptr to the scsi host templ
801  * @priv_size: size of private data after fc_lport
802  *
803  * Returns: ptr to Scsi_Host
804  */
805 static inline struct Scsi_Host *
806 libfc_host_alloc(struct scsi_host_template *sht, int priv_size)
807 {
808 	return scsi_host_alloc(sht, sizeof(struct fc_lport) + priv_size);
809 }
810 
811 /*
812  * LOCAL PORT LAYER
813  *****************************/
814 int fc_lport_init(struct fc_lport *lp);
815 
816 /*
817  * Destroy the specified local port by finding and freeing all
818  * fc_rports associated with it and then by freeing the fc_lport
819  * itself.
820  */
821 int fc_lport_destroy(struct fc_lport *lp);
822 
823 /*
824  * Logout the specified local port from the fabric
825  */
826 int fc_fabric_logoff(struct fc_lport *lp);
827 
828 /*
829  * Initiate the LP state machine. This handler will use fc_host_attr
830  * to store the FLOGI service parameters, so fc_host_attr must be
831  * initialized before calling this handler.
832  */
833 int fc_fabric_login(struct fc_lport *lp);
834 
835 /*
836  * The link is up for the given local port.
837  */
838 void fc_linkup(struct fc_lport *);
839 
840 /*
841  * Link is down for the given local port.
842  */
843 void fc_linkdown(struct fc_lport *);
844 
845 /*
846  * Configure the local port.
847  */
848 int fc_lport_config(struct fc_lport *);
849 
850 /*
851  * Reset the local port.
852  */
853 int fc_lport_reset(struct fc_lport *);
854 
855 /*
856  * Set the mfs or reset
857  */
858 int fc_set_mfs(struct fc_lport *lp, u32 mfs);
859 
860 
861 /*
862  * REMOTE PORT LAYER
863  *****************************/
864 int fc_rport_init(struct fc_lport *lp);
865 void fc_rport_terminate_io(struct fc_rport *rp);
866 
867 /*
868  * DISCOVERY LAYER
869  *****************************/
870 int fc_disc_init(struct fc_lport *lp);
871 
872 
873 /*
874  * SCSI LAYER
875  *****************************/
876 /*
877  * Initialize the SCSI block of libfc
878  */
879 int fc_fcp_init(struct fc_lport *);
880 
881 /*
882  * This section provides an API which allows direct interaction
883  * with the SCSI-ml. Each of these functions satisfies a function
884  * pointer defined in Scsi_Host and therefore is always called
885  * directly from the SCSI-ml.
886  */
887 int fc_queuecommand(struct scsi_cmnd *sc_cmd,
888 		    void (*done)(struct scsi_cmnd *));
889 
890 /*
891  * complete processing of a fcp packet
892  *
893  * This function may sleep if a fsp timer is pending.
894  * The host lock must not be held by caller.
895  */
896 void fc_fcp_complete(struct fc_fcp_pkt *fsp);
897 
898 /*
899  * Send an ABTS frame to the target device. The sc_cmd argument
900  * is a pointer to the SCSI command to be aborted.
901  */
902 int fc_eh_abort(struct scsi_cmnd *sc_cmd);
903 
904 /*
905  * Reset a LUN by sending send the tm cmd to the target.
906  */
907 int fc_eh_device_reset(struct scsi_cmnd *sc_cmd);
908 
909 /*
910  * Reset the host adapter.
911  */
912 int fc_eh_host_reset(struct scsi_cmnd *sc_cmd);
913 
914 /*
915  * Check rport status.
916  */
917 int fc_slave_alloc(struct scsi_device *sdev);
918 
919 /*
920  * Adjust the queue depth.
921  */
922 int fc_change_queue_depth(struct scsi_device *sdev, int qdepth);
923 
924 /*
925  * Change the tag type.
926  */
927 int fc_change_queue_type(struct scsi_device *sdev, int tag_type);
928 
929 /*
930  * Free memory pools used by the FCP layer.
931  */
932 void fc_fcp_destroy(struct fc_lport *);
933 
934 /*
935  * Set up direct-data placement for this I/O request
936  */
937 void fc_fcp_ddp_setup(struct fc_fcp_pkt *fsp, u16 xid);
938 
939 /*
940  * ELS/CT interface
941  *****************************/
942 /*
943  * Initializes ELS/CT interface
944  */
945 int fc_elsct_init(struct fc_lport *lp);
946 
947 
948 /*
949  * EXCHANGE MANAGER LAYER
950  *****************************/
951 /*
952  * Initializes Exchange Manager related
953  * function pointers in struct libfc_function_template.
954  */
955 int fc_exch_init(struct fc_lport *lp);
956 
957 /*
958  * Adds Exchange Manager (EM) mp to lport.
959  *
960  * Adds specified mp to lport using struct fc_exch_mgr_anchor,
961  * the struct fc_exch_mgr_anchor allows same EM sharing by
962  * more than one lport with their specified match function,
963  * the match function is used in allocating exchange from
964  * added mp.
965  */
966 struct fc_exch_mgr_anchor *fc_exch_mgr_add(struct fc_lport *lport,
967 					   struct fc_exch_mgr *mp,
968 					   bool (*match)(struct fc_frame *));
969 
970 /*
971  * Deletes Exchange Manager (EM) from lport by removing
972  * its anchor ema from lport.
973  *
974  * If removed anchor ema was the last user of its associated EM
975  * then also destroys associated EM.
976  */
977 void fc_exch_mgr_del(struct fc_exch_mgr_anchor *ema);
978 
979 /*
980  * Allocates an Exchange Manager (EM).
981  *
982  * The EM manages exchanges for their allocation and
983  * free, also allows exchange lookup for received
984  * frame.
985  *
986  * The class is used for initializing FC class of
987  * allocated exchange from EM.
988  *
989  * The min_xid and max_xid will limit new
990  * exchange ID (XID) within this range for
991  * a new exchange.
992  * The LLD may choose to have multiple EMs,
993  * e.g. one EM instance per CPU receive thread in LLD.
994  *
995  * Specified match function is used in allocating exchanges
996  * from newly allocated EM.
997  */
998 struct fc_exch_mgr *fc_exch_mgr_alloc(struct fc_lport *lp,
999 				      enum fc_class class,
1000 				      u16 min_xid,
1001 				      u16 max_xid,
1002 				      bool (*match)(struct fc_frame *));
1003 
1004 /*
1005  * Free all exchange managers of a lport.
1006  */
1007 void fc_exch_mgr_free(struct fc_lport *lport);
1008 
1009 /*
1010  * Receive a frame on specified local port and exchange manager.
1011  */
1012 void fc_exch_recv(struct fc_lport *lp, struct fc_frame *fp);
1013 
1014 /*
1015  * This function is for exch_seq_send function pointer in
1016  * struct libfc_function_template, see comment block on
1017  * exch_seq_send for description of this function.
1018  */
1019 struct fc_seq *fc_exch_seq_send(struct fc_lport *lp,
1020 				struct fc_frame *fp,
1021 				void (*resp)(struct fc_seq *sp,
1022 					     struct fc_frame *fp,
1023 					     void *arg),
1024 				void (*destructor)(struct fc_seq *sp,
1025 						   void *arg),
1026 				void *arg, u32 timer_msec);
1027 
1028 /*
1029  * send a frame using existing sequence and exchange.
1030  */
1031 int fc_seq_send(struct fc_lport *lp, struct fc_seq *sp, struct fc_frame *fp);
1032 
1033 /*
1034  * Send ELS response using mainly infomation
1035  * in exchange and sequence in EM layer.
1036  */
1037 void fc_seq_els_rsp_send(struct fc_seq *sp, enum fc_els_cmd els_cmd,
1038 			 struct fc_seq_els_data *els_data);
1039 
1040 /*
1041  * This function is for seq_exch_abort function pointer in
1042  * struct libfc_function_template, see comment block on
1043  * seq_exch_abort for description of this function.
1044  */
1045 int fc_seq_exch_abort(const struct fc_seq *req_sp, unsigned int timer_msec);
1046 
1047 /*
1048  * Indicate that an exchange/sequence tuple is complete and the memory
1049  * allocated for the related objects may be freed.
1050  */
1051 void fc_exch_done(struct fc_seq *sp);
1052 
1053 /*
1054  * Allocate a new exchange and sequence pair.
1055  */
1056 struct fc_exch *fc_exch_alloc(struct fc_lport *lport, struct fc_frame *fp);
1057 /*
1058  * Start a new sequence on the same exchange as the supplied sequence.
1059  */
1060 struct fc_seq *fc_seq_start_next(struct fc_seq *sp);
1061 
1062 
1063 /*
1064  * Reset all EMs of a lport, releasing its all sequences and
1065  * exchanges. If sid is non-zero, then reset only exchanges
1066  * we sourced from that FID. If did is non-zero, reset only
1067  * exchanges destined to that FID.
1068  */
1069 void fc_exch_mgr_reset(struct fc_lport *, u32 s_id, u32 d_id);
1070 
1071 /*
1072  * Functions for fc_functions_template
1073  */
1074 void fc_get_host_speed(struct Scsi_Host *shost);
1075 void fc_get_host_port_type(struct Scsi_Host *shost);
1076 void fc_get_host_port_state(struct Scsi_Host *shost);
1077 void fc_set_rport_loss_tmo(struct fc_rport *rport, u32 timeout);
1078 struct fc_host_statistics *fc_get_host_stats(struct Scsi_Host *);
1079 
1080 /*
1081  * module setup functions.
1082  */
1083 int fc_setup_exch_mgr(void);
1084 void fc_destroy_exch_mgr(void);
1085 int fc_setup_rport(void);
1086 void fc_destroy_rport(void);
1087 
1088 /*
1089  * Internal libfc functions.
1090  */
1091 const char *fc_els_resp_type(struct fc_frame *);
1092 
1093 #endif /* _LIBFC_H_ */
1094