xref: /openbmc/linux/include/scsi/libfc.h (revision b2f0091f)
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(rport, fmt, args...)				\
79 do {									\
80 	struct fc_rport_libfc_priv *rdata = rport->dd_data;		\
81 	struct fc_lport *lport = rdata->local_port;			\
82 	FC_RPORT_ID_DBG(lport, rport->port_id, fmt, ##args);		\
83 } while (0)
84 
85 #define FC_FCP_DBG(pkt, fmt, args...)					\
86 	FC_CHECK_LOGGING(FC_FCP_LOGGING,				\
87 			 printk(KERN_INFO "host%u: fcp: %6x: " fmt,	\
88 				(pkt)->lp->host->host_no,		\
89 				pkt->rport->port_id, ##args))
90 
91 #define FC_EXCH_DBG(exch, fmt, args...)					\
92 	FC_CHECK_LOGGING(FC_EXCH_LOGGING,				\
93 			 printk(KERN_INFO "host%u: xid %4x: " fmt,	\
94 				(exch)->lp->host->host_no,		\
95 				exch->xid, ##args))
96 
97 #define FC_SCSI_DBG(lport, fmt, args...)				\
98 	FC_CHECK_LOGGING(FC_SCSI_LOGGING,                               \
99 			 printk(KERN_INFO "host%u: scsi: " fmt,		\
100 				(lport)->host->host_no,	##args))
101 
102 /*
103  * libfc error codes
104  */
105 #define	FC_NO_ERR	0	/* no error */
106 #define	FC_EX_TIMEOUT	1	/* Exchange timeout */
107 #define	FC_EX_CLOSED	2	/* Exchange closed */
108 
109 /* some helpful macros */
110 
111 #define ntohll(x) be64_to_cpu(x)
112 #define htonll(x) cpu_to_be64(x)
113 
114 #define ntoh24(p) (((p)[0] << 16) | ((p)[1] << 8) | ((p)[2]))
115 
116 #define hton24(p, v)	do {			\
117 		p[0] = (((v) >> 16) & 0xFF);	\
118 		p[1] = (((v) >> 8) & 0xFF);	\
119 		p[2] = ((v) & 0xFF);		\
120 	} while (0)
121 
122 /*
123  * FC HBA status
124  */
125 enum fc_lport_state {
126 	LPORT_ST_DISABLED = 0,
127 	LPORT_ST_FLOGI,
128 	LPORT_ST_DNS,
129 	LPORT_ST_RPN_ID,
130 	LPORT_ST_RFT_ID,
131 	LPORT_ST_SCR,
132 	LPORT_ST_READY,
133 	LPORT_ST_LOGO,
134 	LPORT_ST_RESET
135 };
136 
137 enum fc_disc_event {
138 	DISC_EV_NONE = 0,
139 	DISC_EV_SUCCESS,
140 	DISC_EV_FAILED
141 };
142 
143 enum fc_rport_state {
144 	RPORT_ST_INIT,		/* initialized */
145 	RPORT_ST_PLOGI,		/* waiting for PLOGI completion */
146 	RPORT_ST_PRLI,		/* waiting for PRLI completion */
147 	RPORT_ST_RTV,		/* waiting for RTV completion */
148 	RPORT_ST_READY,		/* ready for use */
149 	RPORT_ST_LOGO,		/* port logout sent */
150 	RPORT_ST_DELETE,	/* port being deleted */
151 };
152 
153 enum fc_rport_trans_state {
154 	FC_PORTSTATE_ROGUE,
155 	FC_PORTSTATE_REAL,
156 };
157 
158 /**
159  * struct fc_disc_port - temporary discovery port to hold rport identifiers
160  * @lp: Fibre Channel host port instance
161  * @peers: node for list management during discovery and RSCN processing
162  * @ids: identifiers structure to pass to fc_remote_port_add()
163  * @rport_work: work struct for starting the rport state machine
164  */
165 struct fc_disc_port {
166 	struct fc_lport             *lp;
167 	struct list_head            peers;
168 	struct fc_rport_identifiers ids;
169 	struct work_struct	    rport_work;
170 };
171 
172 enum fc_rport_event {
173 	RPORT_EV_NONE = 0,
174 	RPORT_EV_CREATED,
175 	RPORT_EV_FAILED,
176 	RPORT_EV_STOP,
177 	RPORT_EV_LOGO
178 };
179 
180 struct fc_rport_operations {
181 	void (*event_callback)(struct fc_lport *, struct fc_rport *,
182 			       enum fc_rport_event);
183 };
184 
185 /**
186  * struct fc_rport_libfc_priv - libfc internal information about a remote port
187  * @local_port: Fibre Channel host port instance
188  * @rp_state: state tracks progress of PLOGI, PRLI, and RTV exchanges
189  * @flags: REC and RETRY supported flags
190  * @max_seq: maximum number of concurrent sequences
191  * @retries: retry count in current state
192  * @e_d_tov: error detect timeout value (in msec)
193  * @r_a_tov: resource allocation timeout value (in msec)
194  * @rp_mutex: mutex protects rport
195  * @retry_work:
196  * @event_callback: Callback for rport READY, FAILED or LOGO
197  */
198 struct fc_rport_libfc_priv {
199 	struct fc_lport		   *local_port;
200 	enum fc_rport_state        rp_state;
201 	u16			   flags;
202 	#define FC_RP_FLAGS_REC_SUPPORTED	(1 << 0)
203 	#define FC_RP_FLAGS_RETRY		(1 << 1)
204 	u16		           max_seq;
205 	unsigned int	           retries;
206 	unsigned int	           e_d_tov;
207 	unsigned int	           r_a_tov;
208 	enum fc_rport_trans_state  trans_state;
209 	struct mutex               rp_mutex;
210 	struct delayed_work	   retry_work;
211 	enum fc_rport_event        event;
212 	struct fc_rport_operations *ops;
213 	struct list_head           peers;
214 	struct work_struct         event_work;
215 };
216 
217 #define PRIV_TO_RPORT(x)						\
218 	(struct fc_rport *)((void *)x - sizeof(struct fc_rport));
219 #define RPORT_TO_PRIV(x)						\
220 	(struct fc_rport_libfc_priv *)((void *)x + sizeof(struct fc_rport));
221 
222 struct fc_rport *fc_rport_rogue_create(struct fc_disc_port *);
223 
224 static inline void fc_rport_set_name(struct fc_rport *rport, u64 wwpn, u64 wwnn)
225 {
226 	rport->node_name = wwnn;
227 	rport->port_name = wwpn;
228 }
229 
230 /*
231  * fcoe stats structure
232  */
233 struct fcoe_dev_stats {
234 	u64		SecondsSinceLastReset;
235 	u64		TxFrames;
236 	u64		TxWords;
237 	u64		RxFrames;
238 	u64		RxWords;
239 	u64		ErrorFrames;
240 	u64		DumpedFrames;
241 	u64		LinkFailureCount;
242 	u64		LossOfSignalCount;
243 	u64		InvalidTxWordCount;
244 	u64		InvalidCRCCount;
245 	u64		InputRequests;
246 	u64		OutputRequests;
247 	u64		ControlRequests;
248 	u64		InputMegabytes;
249 	u64		OutputMegabytes;
250 };
251 
252 /*
253  * els data is used for passing ELS respone specific
254  * data to send ELS response mainly using infomation
255  * in exchange and sequence in EM layer.
256  */
257 struct fc_seq_els_data {
258 	struct fc_frame *fp;
259 	enum fc_els_rjt_reason reason;
260 	enum fc_els_rjt_explan explan;
261 };
262 
263 /*
264  * FCP request structure, one for each scsi cmd request
265  */
266 struct fc_fcp_pkt {
267 	/*
268 	 * housekeeping stuff
269 	 */
270 	struct fc_lport *lp;	/* handle to hba struct */
271 	u16		state;		/* scsi_pkt state state */
272 	u16		tgt_flags;	/* target flags	 */
273 	atomic_t	ref_cnt;	/* fcp pkt ref count */
274 	spinlock_t	scsi_pkt_lock;	/* Must be taken before the host lock
275 					 * if both are held at the same time */
276 	/*
277 	 * SCSI I/O related stuff
278 	 */
279 	struct scsi_cmnd *cmd;		/* scsi command pointer. set/clear
280 					 * under host lock */
281 	struct list_head list;		/* tracks queued commands. access under
282 					 * host lock */
283 	/*
284 	 * timeout related stuff
285 	 */
286 	struct timer_list timer;	/* command timer */
287 	struct completion tm_done;
288 	int	wait_for_comp;
289 	unsigned long	start_time;	/* start jiffie */
290 	unsigned long	end_time;	/* end jiffie */
291 	unsigned long	last_pkt_time;	 /* jiffies of last frame received */
292 
293 	/*
294 	 * scsi cmd and data transfer information
295 	 */
296 	u32		data_len;
297 	/*
298 	 * transport related veriables
299 	 */
300 	struct fcp_cmnd cdb_cmd;
301 	size_t		xfer_len;
302 	u16		xfer_ddp;	/* this xfer is ddped */
303 	u32		xfer_contig_end; /* offset of end of contiguous xfer */
304 	u16		max_payload;	/* max payload size in bytes */
305 
306 	/*
307 	 * scsi/fcp return status
308 	 */
309 	u32		io_status;	/* SCSI result upper 24 bits */
310 	u8		cdb_status;
311 	u8		status_code;	/* FCP I/O status */
312 	/* bit 3 Underrun bit 2: overrun */
313 	u8		scsi_comp_flags;
314 	u32		req_flags;	/* bit 0: read bit:1 write */
315 	u32		scsi_resid;	/* residule length */
316 
317 	struct fc_rport	*rport;		/* remote port pointer */
318 	struct fc_seq	*seq_ptr;	/* current sequence pointer */
319 	/*
320 	 * Error Processing
321 	 */
322 	u8		recov_retry;	/* count of recovery retries */
323 	struct fc_seq	*recov_seq;	/* sequence for REC or SRR */
324 };
325 /*
326  * FC_FCP HELPER FUNCTIONS
327  *****************************/
328 static inline bool fc_fcp_is_read(const struct fc_fcp_pkt *fsp)
329 {
330 	if (fsp && fsp->cmd)
331 		return fsp->cmd->sc_data_direction == DMA_FROM_DEVICE;
332 	return false;
333 }
334 
335 /*
336  * Structure and function definitions for managing Fibre Channel Exchanges
337  * and Sequences
338  *
339  * fc_exch holds state for one exchange and links to its active sequence.
340  *
341  * fc_seq holds the state for an individual sequence.
342  */
343 
344 struct fc_exch_mgr;
345 struct fc_exch_mgr_anchor;
346 extern u16	fc_cpu_mask;	/* cpu mask for possible cpus */
347 
348 /*
349  * Sequence.
350  */
351 struct fc_seq {
352 	u8	id;		/* seq ID */
353 	u16	ssb_stat;	/* status flags for sequence status block */
354 	u16	cnt;		/* frames sent so far on sequence */
355 	u32	rec_data;	/* FC-4 value for REC */
356 };
357 
358 #define FC_EX_DONE		(1 << 0) /* ep is completed */
359 #define FC_EX_RST_CLEANUP	(1 << 1) /* reset is forcing completion */
360 
361 /*
362  * Exchange.
363  *
364  * Locking notes: The ex_lock protects following items:
365  *	state, esb_stat, f_ctl, seq.ssb_stat
366  *	seq_id
367  *	sequence allocation
368  */
369 struct fc_exch {
370 	struct fc_exch_mgr *em;		/* exchange manager */
371 	struct fc_exch_pool *pool;	/* per cpu exches pool */
372 	u32		state;		/* internal driver state */
373 	u16		xid;		/* our exchange ID */
374 	struct list_head	ex_list;	/* free or busy list linkage */
375 	spinlock_t	ex_lock;	/* lock covering exchange state */
376 	atomic_t	ex_refcnt;	/* reference counter */
377 	struct delayed_work timeout_work; /* timer for upper level protocols */
378 	struct fc_lport	*lp;		/* fc device instance */
379 	u16		oxid;		/* originator's exchange ID */
380 	u16		rxid;		/* responder's exchange ID */
381 	u32		oid;		/* originator's FCID */
382 	u32		sid;		/* source FCID */
383 	u32		did;		/* destination FCID */
384 	u32		esb_stat;	/* exchange status for ESB */
385 	u32		r_a_tov;	/* r_a_tov from rport (msec) */
386 	u8		seq_id;		/* next sequence ID to use */
387 	u32		f_ctl;		/* F_CTL flags for sequences */
388 	u8		fh_type;	/* frame type */
389 	enum fc_class	class;		/* class of service */
390 	struct fc_seq	seq;		/* single sequence */
391 	/*
392 	 * Handler for responses to this current exchange.
393 	 */
394 	void		(*resp)(struct fc_seq *, struct fc_frame *, void *);
395 	void		(*destructor)(struct fc_seq *, void *);
396 	/*
397 	 * arg is passed as void pointer to exchange
398 	 * resp and destructor handlers
399 	 */
400 	void		*arg;
401 };
402 #define	fc_seq_exch(sp) container_of(sp, struct fc_exch, seq)
403 
404 struct libfc_function_template {
405 
406 	/*
407 	 * Interface to send a FC frame
408 	 *
409 	 * STATUS: REQUIRED
410 	 */
411 	int (*frame_send)(struct fc_lport *lp, struct fc_frame *fp);
412 
413 	/*
414 	 * Interface to send ELS/CT frames
415 	 *
416 	 * STATUS: OPTIONAL
417 	 */
418 	struct fc_seq *(*elsct_send)(struct fc_lport *lport,
419 				     struct fc_rport *rport,
420 				     struct fc_frame *fp,
421 				     unsigned int op,
422 				     void (*resp)(struct fc_seq *,
423 					     struct fc_frame *fp,
424 					     void *arg),
425 				     void *arg, u32 timer_msec);
426 
427 	/*
428 	 * Send the FC frame payload using a new exchange and sequence.
429 	 *
430 	 * The frame pointer with some of the header's fields must be
431 	 * filled before calling exch_seq_send(), those fields are,
432 	 *
433 	 * - routing control
434 	 * - FC port did
435 	 * - FC port sid
436 	 * - FC header type
437 	 * - frame control
438 	 * - parameter or relative offset
439 	 *
440 	 * The exchange response handler is set in this routine to resp()
441 	 * function pointer. It can be called in two scenarios: if a timeout
442 	 * occurs or if a response frame is received for the exchange. The
443 	 * fc_frame pointer in response handler will also indicate timeout
444 	 * as error using IS_ERR related macros.
445 	 *
446 	 * The exchange destructor handler is also set in this routine.
447 	 * The destructor handler is invoked by EM layer when exchange
448 	 * is about to free, this can be used by caller to free its
449 	 * resources along with exchange free.
450 	 *
451 	 * The arg is passed back to resp and destructor handler.
452 	 *
453 	 * The timeout value (in msec) for an exchange is set if non zero
454 	 * timer_msec argument is specified. The timer is canceled when
455 	 * it fires or when the exchange is done. The exchange timeout handler
456 	 * is registered by EM layer.
457 	 *
458 	 * STATUS: OPTIONAL
459 	 */
460 	struct fc_seq *(*exch_seq_send)(struct fc_lport *lp,
461 					struct fc_frame *fp,
462 					void (*resp)(struct fc_seq *sp,
463 						     struct fc_frame *fp,
464 						     void *arg),
465 					void (*destructor)(struct fc_seq *sp,
466 							   void *arg),
467 					void *arg, unsigned int timer_msec);
468 
469 	/*
470 	 * Sets up the DDP context for a given exchange id on the given
471 	 * scatterlist if LLD supports DDP for large receive.
472 	 *
473 	 * STATUS: OPTIONAL
474 	 */
475 	int (*ddp_setup)(struct fc_lport *lp, u16 xid,
476 			 struct scatterlist *sgl, unsigned int sgc);
477 	/*
478 	 * Completes the DDP transfer and returns the length of data DDPed
479 	 * for the given exchange id.
480 	 *
481 	 * STATUS: OPTIONAL
482 	 */
483 	int (*ddp_done)(struct fc_lport *lp, u16 xid);
484 	/*
485 	 * Send a frame using an existing sequence and exchange.
486 	 *
487 	 * STATUS: OPTIONAL
488 	 */
489 	int (*seq_send)(struct fc_lport *lp, struct fc_seq *sp,
490 			struct fc_frame *fp);
491 
492 	/*
493 	 * Send an ELS response using infomation from a previous
494 	 * exchange and sequence.
495 	 *
496 	 * STATUS: OPTIONAL
497 	 */
498 	void (*seq_els_rsp_send)(struct fc_seq *sp, enum fc_els_cmd els_cmd,
499 				 struct fc_seq_els_data *els_data);
500 
501 	/*
502 	 * Abort an exchange and sequence. Generally called because of a
503 	 * exchange timeout or an abort from the upper layer.
504 	 *
505 	 * A timer_msec can be specified for abort timeout, if non-zero
506 	 * timer_msec value is specified then exchange resp handler
507 	 * will be called with timeout error if no response to abort.
508 	 *
509 	 * STATUS: OPTIONAL
510 	 */
511 	int (*seq_exch_abort)(const struct fc_seq *req_sp,
512 			      unsigned int timer_msec);
513 
514 	/*
515 	 * Indicate that an exchange/sequence tuple is complete and the memory
516 	 * allocated for the related objects may be freed.
517 	 *
518 	 * STATUS: OPTIONAL
519 	 */
520 	void (*exch_done)(struct fc_seq *sp);
521 
522 	/*
523 	 * Start a new sequence on the same exchange/sequence tuple.
524 	 *
525 	 * STATUS: OPTIONAL
526 	 */
527 	struct fc_seq *(*seq_start_next)(struct fc_seq *sp);
528 
529 	/*
530 	 * Reset an exchange manager, completing all sequences and exchanges.
531 	 * If s_id is non-zero, reset only exchanges originating from that FID.
532 	 * If d_id is non-zero, reset only exchanges sending to that FID.
533 	 *
534 	 * STATUS: OPTIONAL
535 	 */
536 	void (*exch_mgr_reset)(struct fc_lport *,
537 			       u32 s_id, u32 d_id);
538 
539 	/*
540 	 * Flush the rport work queue. Generally used before shutdown.
541 	 *
542 	 * STATUS: OPTIONAL
543 	 */
544 	void (*rport_flush_queue)(void);
545 
546 	/*
547 	 * Receive a frame for a local port.
548 	 *
549 	 * STATUS: OPTIONAL
550 	 */
551 	void (*lport_recv)(struct fc_lport *lp, struct fc_seq *sp,
552 			   struct fc_frame *fp);
553 
554 	/*
555 	 * Reset the local port.
556 	 *
557 	 * STATUS: OPTIONAL
558 	 */
559 	int (*lport_reset)(struct fc_lport *);
560 
561 	/*
562 	 * Create a remote port
563 	 */
564 	struct fc_rport *(*rport_create)(struct fc_disc_port *);
565 
566 	/*
567 	 * Initiates the RP state machine. It is called from the LP module.
568 	 * This function will issue the following commands to the N_Port
569 	 * identified by the FC ID provided.
570 	 *
571 	 * - PLOGI
572 	 * - PRLI
573 	 * - RTV
574 	 *
575 	 * STATUS: OPTIONAL
576 	 */
577 	int (*rport_login)(struct fc_rport *rport);
578 
579 	/*
580 	 * Logoff, and remove the rport from the transport if
581 	 * it had been added. This will send a LOGO to the target.
582 	 *
583 	 * STATUS: OPTIONAL
584 	 */
585 	int (*rport_logoff)(struct fc_rport *rport);
586 
587 	/*
588 	 * Recieve a request from a remote port.
589 	 *
590 	 * STATUS: OPTIONAL
591 	 */
592 	void (*rport_recv_req)(struct fc_seq *, struct fc_frame *,
593 			       struct fc_rport *);
594 
595 	/*
596 	 * lookup an rport by it's port ID.
597 	 *
598 	 * STATUS: OPTIONAL
599 	 */
600 	struct fc_rport *(*rport_lookup)(const struct fc_lport *, u32);
601 
602 	/*
603 	 * Send a fcp cmd from fsp pkt.
604 	 * Called with the SCSI host lock unlocked and irqs disabled.
605 	 *
606 	 * The resp handler is called when FCP_RSP received.
607 	 *
608 	 * STATUS: OPTIONAL
609 	 */
610 	int (*fcp_cmd_send)(struct fc_lport *lp, struct fc_fcp_pkt *fsp,
611 			    void (*resp)(struct fc_seq *, struct fc_frame *fp,
612 					 void *arg));
613 
614 	/*
615 	 * Cleanup the FCP layer, used durring link down and reset
616 	 *
617 	 * STATUS: OPTIONAL
618 	 */
619 	void (*fcp_cleanup)(struct fc_lport *lp);
620 
621 	/*
622 	 * Abort all I/O on a local port
623 	 *
624 	 * STATUS: OPTIONAL
625 	 */
626 	void (*fcp_abort_io)(struct fc_lport *lp);
627 
628 	/*
629 	 * Receive a request for the discovery layer.
630 	 *
631 	 * STATUS: OPTIONAL
632 	 */
633 	void (*disc_recv_req)(struct fc_seq *,
634 			      struct fc_frame *, struct fc_lport *);
635 
636 	/*
637 	 * Start discovery for a local port.
638 	 *
639 	 * STATUS: OPTIONAL
640 	 */
641 	void (*disc_start)(void (*disc_callback)(struct fc_lport *,
642 						 enum fc_disc_event),
643 			   struct fc_lport *);
644 
645 	/*
646 	 * Stop discovery for a given lport. This will remove
647 	 * all discovered rports
648 	 *
649 	 * STATUS: OPTIONAL
650 	 */
651 	void (*disc_stop) (struct fc_lport *);
652 
653 	/*
654 	 * Stop discovery for a given lport. This will block
655 	 * until all discovered rports are deleted from the
656 	 * FC transport class
657 	 *
658 	 * STATUS: OPTIONAL
659 	 */
660 	void (*disc_stop_final) (struct fc_lport *);
661 };
662 
663 /* information used by the discovery layer */
664 struct fc_disc {
665 	unsigned char		retry_count;
666 	unsigned char		delay;
667 	unsigned char		pending;
668 	unsigned char		requested;
669 	unsigned short		seq_count;
670 	unsigned char		buf_len;
671 	enum fc_disc_event	event;
672 
673 	void (*disc_callback)(struct fc_lport *,
674 			      enum fc_disc_event);
675 
676 	struct list_head	 rports;
677 	struct list_head	 rogue_rports;
678 	struct fc_lport		*lport;
679 	struct mutex		disc_mutex;
680 	struct fc_gpn_ft_resp	partial_buf;	/* partial name buffer */
681 	struct delayed_work	disc_work;
682 };
683 
684 struct fc_lport {
685 	struct list_head list;
686 
687 	/* Associations */
688 	struct Scsi_Host	*host;
689 	struct list_head	ema_list;
690 	struct fc_rport		*dns_rp;
691 	struct fc_rport		*ptp_rp;
692 	void			*scsi_priv;
693 	struct fc_disc          disc;
694 
695 	/* Operational Information */
696 	struct libfc_function_template tt;
697 	u8			link_up;
698 	u8			qfull;
699 	enum fc_lport_state	state;
700 	unsigned long		boot_time;
701 
702 	struct fc_host_statistics host_stats;
703 	struct fcoe_dev_stats	*dev_stats;
704 
705 	u64			wwpn;
706 	u64			wwnn;
707 	u8			retry_count;
708 
709 	/* Capabilities */
710 	u32			sg_supp:1;	/* scatter gather supported */
711 	u32			seq_offload:1;	/* seq offload supported */
712 	u32			crc_offload:1;	/* crc offload supported */
713 	u32			lro_enabled:1;	/* large receive offload */
714 	u32			mfs;	        /* max FC payload size */
715 	unsigned int		service_params;
716 	unsigned int		e_d_tov;
717 	unsigned int		r_a_tov;
718 	u8			max_retry_count;
719 	u8			max_rport_retry_count;
720 	u16			link_speed;
721 	u16			link_supported_speeds;
722 	u16			lro_xid;	/* max xid for fcoe lro */
723 	unsigned int		lso_max;	/* max large send size */
724 	struct fc_ns_fts	fcts;	        /* FC-4 type masks */
725 	struct fc_els_rnid_gen	rnid_gen;	/* RNID information */
726 
727 	/* Semaphores */
728 	struct mutex lp_mutex;
729 
730 	/* Miscellaneous */
731 	struct delayed_work	retry_work;
732 	struct delayed_work	disc_work;
733 };
734 
735 /*
736  * FC_LPORT HELPER FUNCTIONS
737  *****************************/
738 static inline int fc_lport_test_ready(struct fc_lport *lp)
739 {
740 	return lp->state == LPORT_ST_READY;
741 }
742 
743 static inline void fc_set_wwnn(struct fc_lport *lp, u64 wwnn)
744 {
745 	lp->wwnn = wwnn;
746 }
747 
748 static inline void fc_set_wwpn(struct fc_lport *lp, u64 wwnn)
749 {
750 	lp->wwpn = wwnn;
751 }
752 
753 static inline void fc_lport_state_enter(struct fc_lport *lp,
754 					enum fc_lport_state state)
755 {
756 	if (state != lp->state)
757 		lp->retry_count = 0;
758 	lp->state = state;
759 }
760 
761 static inline int fc_lport_init_stats(struct fc_lport *lp)
762 {
763 	/* allocate per cpu stats block */
764 	lp->dev_stats = alloc_percpu(struct fcoe_dev_stats);
765 	if (!lp->dev_stats)
766 		return -ENOMEM;
767 	return 0;
768 }
769 
770 static inline void fc_lport_free_stats(struct fc_lport *lp)
771 {
772 	free_percpu(lp->dev_stats);
773 }
774 
775 static inline struct fcoe_dev_stats *fc_lport_get_stats(struct fc_lport *lp)
776 {
777 	return per_cpu_ptr(lp->dev_stats, smp_processor_id());
778 }
779 
780 static inline void *lport_priv(const struct fc_lport *lp)
781 {
782 	return (void *)(lp + 1);
783 }
784 
785 /**
786  * libfc_host_alloc() - Allocate a Scsi_Host with room for the fc_lport
787  * @sht: ptr to the scsi host templ
788  * @priv_size: size of private data after fc_lport
789  *
790  * Returns: ptr to Scsi_Host
791  */
792 static inline struct Scsi_Host *
793 libfc_host_alloc(struct scsi_host_template *sht, int priv_size)
794 {
795 	return scsi_host_alloc(sht, sizeof(struct fc_lport) + priv_size);
796 }
797 
798 /*
799  * LOCAL PORT LAYER
800  *****************************/
801 int fc_lport_init(struct fc_lport *lp);
802 
803 /*
804  * Destroy the specified local port by finding and freeing all
805  * fc_rports associated with it and then by freeing the fc_lport
806  * itself.
807  */
808 int fc_lport_destroy(struct fc_lport *lp);
809 
810 /*
811  * Logout the specified local port from the fabric
812  */
813 int fc_fabric_logoff(struct fc_lport *lp);
814 
815 /*
816  * Initiate the LP state machine. This handler will use fc_host_attr
817  * to store the FLOGI service parameters, so fc_host_attr must be
818  * initialized before calling this handler.
819  */
820 int fc_fabric_login(struct fc_lport *lp);
821 
822 /*
823  * The link is up for the given local port.
824  */
825 void fc_linkup(struct fc_lport *);
826 
827 /*
828  * Link is down for the given local port.
829  */
830 void fc_linkdown(struct fc_lport *);
831 
832 /*
833  * Configure the local port.
834  */
835 int fc_lport_config(struct fc_lport *);
836 
837 /*
838  * Reset the local port.
839  */
840 int fc_lport_reset(struct fc_lport *);
841 
842 /*
843  * Set the mfs or reset
844  */
845 int fc_set_mfs(struct fc_lport *lp, u32 mfs);
846 
847 
848 /*
849  * REMOTE PORT LAYER
850  *****************************/
851 int fc_rport_init(struct fc_lport *lp);
852 void fc_rport_terminate_io(struct fc_rport *rp);
853 
854 /*
855  * DISCOVERY LAYER
856  *****************************/
857 int fc_disc_init(struct fc_lport *lp);
858 
859 
860 /*
861  * SCSI LAYER
862  *****************************/
863 /*
864  * Initialize the SCSI block of libfc
865  */
866 int fc_fcp_init(struct fc_lport *);
867 
868 /*
869  * This section provides an API which allows direct interaction
870  * with the SCSI-ml. Each of these functions satisfies a function
871  * pointer defined in Scsi_Host and therefore is always called
872  * directly from the SCSI-ml.
873  */
874 int fc_queuecommand(struct scsi_cmnd *sc_cmd,
875 		    void (*done)(struct scsi_cmnd *));
876 
877 /*
878  * complete processing of a fcp packet
879  *
880  * This function may sleep if a fsp timer is pending.
881  * The host lock must not be held by caller.
882  */
883 void fc_fcp_complete(struct fc_fcp_pkt *fsp);
884 
885 /*
886  * Send an ABTS frame to the target device. The sc_cmd argument
887  * is a pointer to the SCSI command to be aborted.
888  */
889 int fc_eh_abort(struct scsi_cmnd *sc_cmd);
890 
891 /*
892  * Reset a LUN by sending send the tm cmd to the target.
893  */
894 int fc_eh_device_reset(struct scsi_cmnd *sc_cmd);
895 
896 /*
897  * Reset the host adapter.
898  */
899 int fc_eh_host_reset(struct scsi_cmnd *sc_cmd);
900 
901 /*
902  * Check rport status.
903  */
904 int fc_slave_alloc(struct scsi_device *sdev);
905 
906 /*
907  * Adjust the queue depth.
908  */
909 int fc_change_queue_depth(struct scsi_device *sdev, int qdepth);
910 
911 /*
912  * Change the tag type.
913  */
914 int fc_change_queue_type(struct scsi_device *sdev, int tag_type);
915 
916 /*
917  * Free memory pools used by the FCP layer.
918  */
919 void fc_fcp_destroy(struct fc_lport *);
920 
921 /*
922  * Set up direct-data placement for this I/O request
923  */
924 void fc_fcp_ddp_setup(struct fc_fcp_pkt *fsp, u16 xid);
925 
926 /*
927  * ELS/CT interface
928  *****************************/
929 /*
930  * Initializes ELS/CT interface
931  */
932 int fc_elsct_init(struct fc_lport *lp);
933 
934 
935 /*
936  * EXCHANGE MANAGER LAYER
937  *****************************/
938 /*
939  * Initializes Exchange Manager related
940  * function pointers in struct libfc_function_template.
941  */
942 int fc_exch_init(struct fc_lport *lp);
943 
944 /*
945  * Adds Exchange Manager (EM) mp to lport.
946  *
947  * Adds specified mp to lport using struct fc_exch_mgr_anchor,
948  * the struct fc_exch_mgr_anchor allows same EM sharing by
949  * more than one lport with their specified match function,
950  * the match function is used in allocating exchange from
951  * added mp.
952  */
953 struct fc_exch_mgr_anchor *fc_exch_mgr_add(struct fc_lport *lport,
954 					   struct fc_exch_mgr *mp,
955 					   bool (*match)(struct fc_frame *));
956 
957 /*
958  * Deletes Exchange Manager (EM) from lport by removing
959  * its anchor ema from lport.
960  *
961  * If removed anchor ema was the last user of its associated EM
962  * then also destroys associated EM.
963  */
964 void fc_exch_mgr_del(struct fc_exch_mgr_anchor *ema);
965 
966 /*
967  * Allocates an Exchange Manager (EM).
968  *
969  * The EM manages exchanges for their allocation and
970  * free, also allows exchange lookup for received
971  * frame.
972  *
973  * The class is used for initializing FC class of
974  * allocated exchange from EM.
975  *
976  * The min_xid and max_xid will limit new
977  * exchange ID (XID) within this range for
978  * a new exchange.
979  * The LLD may choose to have multiple EMs,
980  * e.g. one EM instance per CPU receive thread in LLD.
981  *
982  * Specified match function is used in allocating exchanges
983  * from newly allocated EM.
984  */
985 struct fc_exch_mgr *fc_exch_mgr_alloc(struct fc_lport *lp,
986 				      enum fc_class class,
987 				      u16 min_xid,
988 				      u16 max_xid,
989 				      bool (*match)(struct fc_frame *));
990 
991 /*
992  * Free all exchange managers of a lport.
993  */
994 void fc_exch_mgr_free(struct fc_lport *lport);
995 
996 /*
997  * Receive a frame on specified local port and exchange manager.
998  */
999 void fc_exch_recv(struct fc_lport *lp, struct fc_frame *fp);
1000 
1001 /*
1002  * This function is for exch_seq_send function pointer in
1003  * struct libfc_function_template, see comment block on
1004  * exch_seq_send for description of this function.
1005  */
1006 struct fc_seq *fc_exch_seq_send(struct fc_lport *lp,
1007 				struct fc_frame *fp,
1008 				void (*resp)(struct fc_seq *sp,
1009 					     struct fc_frame *fp,
1010 					     void *arg),
1011 				void (*destructor)(struct fc_seq *sp,
1012 						   void *arg),
1013 				void *arg, u32 timer_msec);
1014 
1015 /*
1016  * send a frame using existing sequence and exchange.
1017  */
1018 int fc_seq_send(struct fc_lport *lp, struct fc_seq *sp, struct fc_frame *fp);
1019 
1020 /*
1021  * Send ELS response using mainly infomation
1022  * in exchange and sequence in EM layer.
1023  */
1024 void fc_seq_els_rsp_send(struct fc_seq *sp, enum fc_els_cmd els_cmd,
1025 			 struct fc_seq_els_data *els_data);
1026 
1027 /*
1028  * This function is for seq_exch_abort function pointer in
1029  * struct libfc_function_template, see comment block on
1030  * seq_exch_abort for description of this function.
1031  */
1032 int fc_seq_exch_abort(const struct fc_seq *req_sp, unsigned int timer_msec);
1033 
1034 /*
1035  * Indicate that an exchange/sequence tuple is complete and the memory
1036  * allocated for the related objects may be freed.
1037  */
1038 void fc_exch_done(struct fc_seq *sp);
1039 
1040 /*
1041  * Allocate a new exchange and sequence pair.
1042  */
1043 struct fc_exch *fc_exch_alloc(struct fc_lport *lport, struct fc_frame *fp);
1044 /*
1045  * Start a new sequence on the same exchange as the supplied sequence.
1046  */
1047 struct fc_seq *fc_seq_start_next(struct fc_seq *sp);
1048 
1049 
1050 /*
1051  * Reset all EMs of a lport, releasing its all sequences and
1052  * exchanges. If sid is non-zero, then reset only exchanges
1053  * we sourced from that FID. If did is non-zero, reset only
1054  * exchanges destined to that FID.
1055  */
1056 void fc_exch_mgr_reset(struct fc_lport *, u32 s_id, u32 d_id);
1057 
1058 /*
1059  * Functions for fc_functions_template
1060  */
1061 void fc_get_host_speed(struct Scsi_Host *shost);
1062 void fc_get_host_port_type(struct Scsi_Host *shost);
1063 void fc_get_host_port_state(struct Scsi_Host *shost);
1064 void fc_set_rport_loss_tmo(struct fc_rport *rport, u32 timeout);
1065 struct fc_host_statistics *fc_get_host_stats(struct Scsi_Host *);
1066 
1067 /*
1068  * module setup functions.
1069  */
1070 int fc_setup_exch_mgr(void);
1071 void fc_destroy_exch_mgr(void);
1072 int fc_setup_rport(void);
1073 void fc_destroy_rport(void);
1074 
1075 #endif /* _LIBFC_H_ */
1076