xref: /openbmc/linux/include/scsi/libfc.h (revision f657d299)
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_DELETE,	/* port being deleted */
147 };
148 
149 /**
150  * struct fc_disc_port - temporary discovery port to hold rport identifiers
151  * @lp:         Fibre Channel host port instance
152  * @peers:      Node for list management during discovery and RSCN processing
153  * @rport_work: Work struct for starting the rport state machine
154  * @port_id:    Port ID of the discovered port
155  */
156 struct fc_disc_port {
157 	struct fc_lport             *lp;
158 	struct list_head            peers;
159 	struct work_struct	    rport_work;
160 	u32                         port_id;
161 };
162 
163 enum fc_rport_event {
164 	RPORT_EV_NONE = 0,
165 	RPORT_EV_READY,
166 	RPORT_EV_FAILED,
167 	RPORT_EV_STOP,
168 	RPORT_EV_LOGO
169 };
170 
171 struct fc_rport_priv;
172 
173 struct fc_rport_operations {
174 	void (*event_callback)(struct fc_lport *, struct fc_rport_priv *,
175 			       enum fc_rport_event);
176 };
177 
178 /**
179  * struct fc_rport_libfc_priv - libfc internal information about a remote port
180  * @local_port: Fibre Channel host port instance
181  * @rp_state: indicates READY for I/O or DELETE when blocked.
182  * @flags: REC and RETRY supported flags
183  * @e_d_tov: error detect timeout value (in msec)
184  * @r_a_tov: resource allocation timeout value (in msec)
185  */
186 struct fc_rport_libfc_priv {
187 	struct fc_lport		   *local_port;
188 	enum fc_rport_state        rp_state;
189 	u16			   flags;
190 	#define FC_RP_FLAGS_REC_SUPPORTED	(1 << 0)
191 	#define FC_RP_FLAGS_RETRY		(1 << 1)
192 	unsigned int	           e_d_tov;
193 	unsigned int	           r_a_tov;
194 };
195 
196 /**
197  * struct fc_rport_priv - libfc rport and discovery info about a remote port
198  * @local_port: Fibre Channel host port instance
199  * @rport: transport remote port
200  * @kref: reference counter
201  * @rp_state: state tracks progress of PLOGI, PRLI, and RTV exchanges
202  * @ids: remote port identifiers and roles
203  * @flags: REC and RETRY supported flags
204  * @max_seq: maximum number of concurrent sequences
205  * @disc_id: discovery identifier
206  * @maxframe_size: maximum frame size
207  * @retries: retry count in current state
208  * @e_d_tov: error detect timeout value (in msec)
209  * @r_a_tov: resource allocation timeout value (in msec)
210  * @rp_mutex: mutex protects rport
211  * @retry_work:
212  * @event_callback: Callback for rport READY, FAILED or LOGO
213  */
214 struct fc_rport_priv {
215 	struct fc_lport		   *local_port;
216 	struct fc_rport		   *rport;
217 	struct kref		   kref;
218 	enum fc_rport_state        rp_state;
219 	struct fc_rport_identifiers ids;
220 	u16			   flags;
221 	u16		           max_seq;
222 	u16			   disc_id;
223 	u16			   maxframe_size;
224 	unsigned int	           retries;
225 	unsigned int	           e_d_tov;
226 	unsigned int	           r_a_tov;
227 	struct mutex               rp_mutex;
228 	struct delayed_work	   retry_work;
229 	enum fc_rport_event        event;
230 	struct fc_rport_operations *ops;
231 	struct list_head           peers;
232 	struct work_struct         event_work;
233 	u32			   supported_classes;
234 };
235 
236 /*
237  * fcoe stats structure
238  */
239 struct fcoe_dev_stats {
240 	u64		SecondsSinceLastReset;
241 	u64		TxFrames;
242 	u64		TxWords;
243 	u64		RxFrames;
244 	u64		RxWords;
245 	u64		ErrorFrames;
246 	u64		DumpedFrames;
247 	u64		LinkFailureCount;
248 	u64		LossOfSignalCount;
249 	u64		InvalidTxWordCount;
250 	u64		InvalidCRCCount;
251 	u64		InputRequests;
252 	u64		OutputRequests;
253 	u64		ControlRequests;
254 	u64		InputMegabytes;
255 	u64		OutputMegabytes;
256 };
257 
258 /*
259  * els data is used for passing ELS respone specific
260  * data to send ELS response mainly using infomation
261  * in exchange and sequence in EM layer.
262  */
263 struct fc_seq_els_data {
264 	struct fc_frame *fp;
265 	enum fc_els_rjt_reason reason;
266 	enum fc_els_rjt_explan explan;
267 };
268 
269 /*
270  * FCP request structure, one for each scsi cmd request
271  */
272 struct fc_fcp_pkt {
273 	/*
274 	 * housekeeping stuff
275 	 */
276 	struct fc_lport *lp;	/* handle to hba struct */
277 	u16		state;		/* scsi_pkt state state */
278 	u16		tgt_flags;	/* target flags	 */
279 	atomic_t	ref_cnt;	/* fcp pkt ref count */
280 	spinlock_t	scsi_pkt_lock;	/* Must be taken before the host lock
281 					 * if both are held at the same time */
282 	/*
283 	 * SCSI I/O related stuff
284 	 */
285 	struct scsi_cmnd *cmd;		/* scsi command pointer. set/clear
286 					 * under host lock */
287 	struct list_head list;		/* tracks queued commands. access under
288 					 * host lock */
289 	/*
290 	 * timeout related stuff
291 	 */
292 	struct timer_list timer;	/* command timer */
293 	struct completion tm_done;
294 	int	wait_for_comp;
295 	unsigned long	start_time;	/* start jiffie */
296 	unsigned long	end_time;	/* end jiffie */
297 	unsigned long	last_pkt_time;	 /* jiffies of last frame received */
298 
299 	/*
300 	 * scsi cmd and data transfer information
301 	 */
302 	u32		data_len;
303 	/*
304 	 * transport related veriables
305 	 */
306 	struct fcp_cmnd cdb_cmd;
307 	size_t		xfer_len;
308 	u16		xfer_ddp;	/* this xfer is ddped */
309 	u32		xfer_contig_end; /* offset of end of contiguous xfer */
310 	u16		max_payload;	/* max payload size in bytes */
311 
312 	/*
313 	 * scsi/fcp return status
314 	 */
315 	u32		io_status;	/* SCSI result upper 24 bits */
316 	u8		cdb_status;
317 	u8		status_code;	/* FCP I/O status */
318 	/* bit 3 Underrun bit 2: overrun */
319 	u8		scsi_comp_flags;
320 	u32		req_flags;	/* bit 0: read bit:1 write */
321 	u32		scsi_resid;	/* residule length */
322 
323 	struct fc_rport	*rport;		/* remote port pointer */
324 	struct fc_seq	*seq_ptr;	/* current sequence pointer */
325 	/*
326 	 * Error Processing
327 	 */
328 	u8		recov_retry;	/* count of recovery retries */
329 	struct fc_seq	*recov_seq;	/* sequence for REC or SRR */
330 };
331 /*
332  * FC_FCP HELPER FUNCTIONS
333  *****************************/
334 static inline bool fc_fcp_is_read(const struct fc_fcp_pkt *fsp)
335 {
336 	if (fsp && fsp->cmd)
337 		return fsp->cmd->sc_data_direction == DMA_FROM_DEVICE;
338 	return false;
339 }
340 
341 /*
342  * Structure and function definitions for managing Fibre Channel Exchanges
343  * and Sequences
344  *
345  * fc_exch holds state for one exchange and links to its active sequence.
346  *
347  * fc_seq holds the state for an individual sequence.
348  */
349 
350 struct fc_exch_mgr;
351 struct fc_exch_mgr_anchor;
352 extern u16	fc_cpu_mask;	/* cpu mask for possible cpus */
353 
354 /*
355  * Sequence.
356  */
357 struct fc_seq {
358 	u8	id;		/* seq ID */
359 	u16	ssb_stat;	/* status flags for sequence status block */
360 	u16	cnt;		/* frames sent so far on sequence */
361 	u32	rec_data;	/* FC-4 value for REC */
362 };
363 
364 #define FC_EX_DONE		(1 << 0) /* ep is completed */
365 #define FC_EX_RST_CLEANUP	(1 << 1) /* reset is forcing completion */
366 
367 /*
368  * Exchange.
369  *
370  * Locking notes: The ex_lock protects following items:
371  *	state, esb_stat, f_ctl, seq.ssb_stat
372  *	seq_id
373  *	sequence allocation
374  */
375 struct fc_exch {
376 	struct fc_exch_mgr *em;		/* exchange manager */
377 	struct fc_exch_pool *pool;	/* per cpu exches pool */
378 	u32		state;		/* internal driver state */
379 	u16		xid;		/* our exchange ID */
380 	struct list_head	ex_list;	/* free or busy list linkage */
381 	spinlock_t	ex_lock;	/* lock covering exchange state */
382 	atomic_t	ex_refcnt;	/* reference counter */
383 	struct delayed_work timeout_work; /* timer for upper level protocols */
384 	struct fc_lport	*lp;		/* fc device instance */
385 	u16		oxid;		/* originator's exchange ID */
386 	u16		rxid;		/* responder's exchange ID */
387 	u32		oid;		/* originator's FCID */
388 	u32		sid;		/* source FCID */
389 	u32		did;		/* destination FCID */
390 	u32		esb_stat;	/* exchange status for ESB */
391 	u32		r_a_tov;	/* r_a_tov from rport (msec) */
392 	u8		seq_id;		/* next sequence ID to use */
393 	u32		f_ctl;		/* F_CTL flags for sequences */
394 	u8		fh_type;	/* frame type */
395 	enum fc_class	class;		/* class of service */
396 	struct fc_seq	seq;		/* single sequence */
397 	/*
398 	 * Handler for responses to this current exchange.
399 	 */
400 	void		(*resp)(struct fc_seq *, struct fc_frame *, void *);
401 	void		(*destructor)(struct fc_seq *, void *);
402 	/*
403 	 * arg is passed as void pointer to exchange
404 	 * resp and destructor handlers
405 	 */
406 	void		*arg;
407 };
408 #define	fc_seq_exch(sp) container_of(sp, struct fc_exch, seq)
409 
410 struct libfc_function_template {
411 
412 	/*
413 	 * Interface to send a FC frame
414 	 *
415 	 * STATUS: REQUIRED
416 	 */
417 	int (*frame_send)(struct fc_lport *lp, struct fc_frame *fp);
418 
419 	/*
420 	 * Interface to send ELS/CT frames
421 	 *
422 	 * STATUS: OPTIONAL
423 	 */
424 	struct fc_seq *(*elsct_send)(struct fc_lport *lport,
425 				     u32 did,
426 				     struct fc_frame *fp,
427 				     unsigned int op,
428 				     void (*resp)(struct fc_seq *,
429 					     struct fc_frame *fp,
430 					     void *arg),
431 				     void *arg, u32 timer_msec);
432 
433 	/*
434 	 * Send the FC frame payload using a new exchange and sequence.
435 	 *
436 	 * The frame pointer with some of the header's fields must be
437 	 * filled before calling exch_seq_send(), those fields are,
438 	 *
439 	 * - routing control
440 	 * - FC port did
441 	 * - FC port sid
442 	 * - FC header type
443 	 * - frame control
444 	 * - parameter or relative offset
445 	 *
446 	 * The exchange response handler is set in this routine to resp()
447 	 * function pointer. It can be called in two scenarios: if a timeout
448 	 * occurs or if a response frame is received for the exchange. The
449 	 * fc_frame pointer in response handler will also indicate timeout
450 	 * as error using IS_ERR related macros.
451 	 *
452 	 * The exchange destructor handler is also set in this routine.
453 	 * The destructor handler is invoked by EM layer when exchange
454 	 * is about to free, this can be used by caller to free its
455 	 * resources along with exchange free.
456 	 *
457 	 * The arg is passed back to resp and destructor handler.
458 	 *
459 	 * The timeout value (in msec) for an exchange is set if non zero
460 	 * timer_msec argument is specified. The timer is canceled when
461 	 * it fires or when the exchange is done. The exchange timeout handler
462 	 * is registered by EM layer.
463 	 *
464 	 * STATUS: OPTIONAL
465 	 */
466 	struct fc_seq *(*exch_seq_send)(struct fc_lport *lp,
467 					struct fc_frame *fp,
468 					void (*resp)(struct fc_seq *sp,
469 						     struct fc_frame *fp,
470 						     void *arg),
471 					void (*destructor)(struct fc_seq *sp,
472 							   void *arg),
473 					void *arg, unsigned int timer_msec);
474 
475 	/*
476 	 * Sets up the DDP context for a given exchange id on the given
477 	 * scatterlist if LLD supports DDP for large receive.
478 	 *
479 	 * STATUS: OPTIONAL
480 	 */
481 	int (*ddp_setup)(struct fc_lport *lp, u16 xid,
482 			 struct scatterlist *sgl, unsigned int sgc);
483 	/*
484 	 * Completes the DDP transfer and returns the length of data DDPed
485 	 * for the given exchange id.
486 	 *
487 	 * STATUS: OPTIONAL
488 	 */
489 	int (*ddp_done)(struct fc_lport *lp, u16 xid);
490 	/*
491 	 * Send a frame using an existing sequence and exchange.
492 	 *
493 	 * STATUS: OPTIONAL
494 	 */
495 	int (*seq_send)(struct fc_lport *lp, struct fc_seq *sp,
496 			struct fc_frame *fp);
497 
498 	/*
499 	 * Send an ELS response using infomation from a previous
500 	 * exchange and sequence.
501 	 *
502 	 * STATUS: OPTIONAL
503 	 */
504 	void (*seq_els_rsp_send)(struct fc_seq *sp, enum fc_els_cmd els_cmd,
505 				 struct fc_seq_els_data *els_data);
506 
507 	/*
508 	 * Abort an exchange and sequence. Generally called because of a
509 	 * exchange timeout or an abort from the upper layer.
510 	 *
511 	 * A timer_msec can be specified for abort timeout, if non-zero
512 	 * timer_msec value is specified then exchange resp handler
513 	 * will be called with timeout error if no response to abort.
514 	 *
515 	 * STATUS: OPTIONAL
516 	 */
517 	int (*seq_exch_abort)(const struct fc_seq *req_sp,
518 			      unsigned int timer_msec);
519 
520 	/*
521 	 * Indicate that an exchange/sequence tuple is complete and the memory
522 	 * allocated for the related objects may be freed.
523 	 *
524 	 * STATUS: OPTIONAL
525 	 */
526 	void (*exch_done)(struct fc_seq *sp);
527 
528 	/*
529 	 * Start a new sequence on the same exchange/sequence tuple.
530 	 *
531 	 * STATUS: OPTIONAL
532 	 */
533 	struct fc_seq *(*seq_start_next)(struct fc_seq *sp);
534 
535 	/*
536 	 * Reset an exchange manager, completing all sequences and exchanges.
537 	 * If s_id is non-zero, reset only exchanges originating from that FID.
538 	 * If d_id is non-zero, reset only exchanges sending to that FID.
539 	 *
540 	 * STATUS: OPTIONAL
541 	 */
542 	void (*exch_mgr_reset)(struct fc_lport *,
543 			       u32 s_id, u32 d_id);
544 
545 	/*
546 	 * Flush the rport work queue. Generally used before shutdown.
547 	 *
548 	 * STATUS: OPTIONAL
549 	 */
550 	void (*rport_flush_queue)(void);
551 
552 	/*
553 	 * Receive a frame for a local port.
554 	 *
555 	 * STATUS: OPTIONAL
556 	 */
557 	void (*lport_recv)(struct fc_lport *lp, struct fc_seq *sp,
558 			   struct fc_frame *fp);
559 
560 	/*
561 	 * Reset the local port.
562 	 *
563 	 * STATUS: OPTIONAL
564 	 */
565 	int (*lport_reset)(struct fc_lport *);
566 
567 	/*
568 	 * Create a remote port with a given port ID
569 	 *
570 	 * STATUS: OPTIONAL
571 	 */
572 	struct fc_rport_priv *(*rport_create)(struct fc_lport *, u32);
573 
574 	/*
575 	 * Initiates the RP state machine. It is called from the LP module.
576 	 * This function will issue the following commands to the N_Port
577 	 * identified by the FC ID provided.
578 	 *
579 	 * - PLOGI
580 	 * - PRLI
581 	 * - RTV
582 	 *
583 	 * STATUS: OPTIONAL
584 	 */
585 	int (*rport_login)(struct fc_rport_priv *);
586 
587 	/*
588 	 * Logoff, and remove the rport from the transport if
589 	 * it had been added. This will send a LOGO to the target.
590 	 *
591 	 * STATUS: OPTIONAL
592 	 */
593 	int (*rport_logoff)(struct fc_rport_priv *);
594 
595 	/*
596 	 * Recieve a request from a remote port.
597 	 *
598 	 * STATUS: OPTIONAL
599 	 */
600 	void (*rport_recv_req)(struct fc_seq *, struct fc_frame *,
601 			       struct fc_lport *);
602 
603 	/*
604 	 * lookup an rport by it's port ID.
605 	 *
606 	 * STATUS: OPTIONAL
607 	 */
608 	struct fc_rport_priv *(*rport_lookup)(const struct fc_lport *, u32);
609 
610 	/*
611 	 * Destroy an rport after final kref_put().
612 	 * The argument is a pointer to the kref inside the fc_rport_priv.
613 	 */
614 	void (*rport_destroy)(struct kref *);
615 
616 	/*
617 	 * Send a fcp cmd from fsp pkt.
618 	 * Called with the SCSI host lock unlocked and irqs disabled.
619 	 *
620 	 * The resp handler is called when FCP_RSP received.
621 	 *
622 	 * STATUS: OPTIONAL
623 	 */
624 	int (*fcp_cmd_send)(struct fc_lport *lp, struct fc_fcp_pkt *fsp,
625 			    void (*resp)(struct fc_seq *, struct fc_frame *fp,
626 					 void *arg));
627 
628 	/*
629 	 * Cleanup the FCP layer, used durring link down and reset
630 	 *
631 	 * STATUS: OPTIONAL
632 	 */
633 	void (*fcp_cleanup)(struct fc_lport *lp);
634 
635 	/*
636 	 * Abort all I/O on a local port
637 	 *
638 	 * STATUS: OPTIONAL
639 	 */
640 	void (*fcp_abort_io)(struct fc_lport *lp);
641 
642 	/*
643 	 * Receive a request for the discovery layer.
644 	 *
645 	 * STATUS: OPTIONAL
646 	 */
647 	void (*disc_recv_req)(struct fc_seq *,
648 			      struct fc_frame *, struct fc_lport *);
649 
650 	/*
651 	 * Start discovery for a local port.
652 	 *
653 	 * STATUS: OPTIONAL
654 	 */
655 	void (*disc_start)(void (*disc_callback)(struct fc_lport *,
656 						 enum fc_disc_event),
657 			   struct fc_lport *);
658 
659 	/*
660 	 * Stop discovery for a given lport. This will remove
661 	 * all discovered rports
662 	 *
663 	 * STATUS: OPTIONAL
664 	 */
665 	void (*disc_stop) (struct fc_lport *);
666 
667 	/*
668 	 * Stop discovery for a given lport. This will block
669 	 * until all discovered rports are deleted from the
670 	 * FC transport class
671 	 *
672 	 * STATUS: OPTIONAL
673 	 */
674 	void (*disc_stop_final) (struct fc_lport *);
675 };
676 
677 /* information used by the discovery layer */
678 struct fc_disc {
679 	unsigned char		retry_count;
680 	unsigned char		pending;
681 	unsigned char		requested;
682 	unsigned short		seq_count;
683 	unsigned char		buf_len;
684 	u16			disc_id;
685 
686 	void (*disc_callback)(struct fc_lport *,
687 			      enum fc_disc_event);
688 
689 	struct list_head	 rports;
690 	struct fc_lport		*lport;
691 	struct mutex		disc_mutex;
692 	struct fc_gpn_ft_resp	partial_buf;	/* partial name buffer */
693 	struct delayed_work	disc_work;
694 };
695 
696 struct fc_lport {
697 	struct list_head list;
698 
699 	/* Associations */
700 	struct Scsi_Host	*host;
701 	struct list_head	ema_list;
702 	struct fc_rport_priv	*dns_rp;
703 	struct fc_rport_priv	*ptp_rp;
704 	void			*scsi_priv;
705 	struct fc_disc          disc;
706 
707 	/* Operational Information */
708 	struct libfc_function_template tt;
709 	u8			link_up;
710 	u8			qfull;
711 	enum fc_lport_state	state;
712 	unsigned long		boot_time;
713 
714 	struct fc_host_statistics host_stats;
715 	struct fcoe_dev_stats	*dev_stats;
716 
717 	u64			wwpn;
718 	u64			wwnn;
719 	u8			retry_count;
720 
721 	/* Capabilities */
722 	u32			sg_supp:1;	/* scatter gather supported */
723 	u32			seq_offload:1;	/* seq offload supported */
724 	u32			crc_offload:1;	/* crc offload supported */
725 	u32			lro_enabled:1;	/* large receive offload */
726 	u32			mfs;	        /* max FC payload size */
727 	unsigned int		service_params;
728 	unsigned int		e_d_tov;
729 	unsigned int		r_a_tov;
730 	u8			max_retry_count;
731 	u8			max_rport_retry_count;
732 	u16			link_speed;
733 	u16			link_supported_speeds;
734 	u16			lro_xid;	/* max xid for fcoe lro */
735 	unsigned int		lso_max;	/* max large send size */
736 	struct fc_ns_fts	fcts;	        /* FC-4 type masks */
737 	struct fc_els_rnid_gen	rnid_gen;	/* RNID information */
738 
739 	/* Semaphores */
740 	struct mutex lp_mutex;
741 
742 	/* Miscellaneous */
743 	struct delayed_work	retry_work;
744 	struct delayed_work	disc_work;
745 };
746 
747 /*
748  * FC_LPORT HELPER FUNCTIONS
749  *****************************/
750 static inline int fc_lport_test_ready(struct fc_lport *lp)
751 {
752 	return lp->state == LPORT_ST_READY;
753 }
754 
755 static inline void fc_set_wwnn(struct fc_lport *lp, u64 wwnn)
756 {
757 	lp->wwnn = wwnn;
758 }
759 
760 static inline void fc_set_wwpn(struct fc_lport *lp, u64 wwnn)
761 {
762 	lp->wwpn = wwnn;
763 }
764 
765 static inline void fc_lport_state_enter(struct fc_lport *lp,
766 					enum fc_lport_state state)
767 {
768 	if (state != lp->state)
769 		lp->retry_count = 0;
770 	lp->state = state;
771 }
772 
773 static inline int fc_lport_init_stats(struct fc_lport *lp)
774 {
775 	/* allocate per cpu stats block */
776 	lp->dev_stats = alloc_percpu(struct fcoe_dev_stats);
777 	if (!lp->dev_stats)
778 		return -ENOMEM;
779 	return 0;
780 }
781 
782 static inline void fc_lport_free_stats(struct fc_lport *lp)
783 {
784 	free_percpu(lp->dev_stats);
785 }
786 
787 static inline struct fcoe_dev_stats *fc_lport_get_stats(struct fc_lport *lp)
788 {
789 	return per_cpu_ptr(lp->dev_stats, smp_processor_id());
790 }
791 
792 static inline void *lport_priv(const struct fc_lport *lp)
793 {
794 	return (void *)(lp + 1);
795 }
796 
797 /**
798  * libfc_host_alloc() - Allocate a Scsi_Host with room for the fc_lport
799  * @sht: ptr to the scsi host templ
800  * @priv_size: size of private data after fc_lport
801  *
802  * Returns: ptr to Scsi_Host
803  */
804 static inline struct Scsi_Host *
805 libfc_host_alloc(struct scsi_host_template *sht, int priv_size)
806 {
807 	return scsi_host_alloc(sht, sizeof(struct fc_lport) + priv_size);
808 }
809 
810 /*
811  * LOCAL PORT LAYER
812  *****************************/
813 int fc_lport_init(struct fc_lport *lp);
814 
815 /*
816  * Destroy the specified local port by finding and freeing all
817  * fc_rports associated with it and then by freeing the fc_lport
818  * itself.
819  */
820 int fc_lport_destroy(struct fc_lport *lp);
821 
822 /*
823  * Logout the specified local port from the fabric
824  */
825 int fc_fabric_logoff(struct fc_lport *lp);
826 
827 /*
828  * Initiate the LP state machine. This handler will use fc_host_attr
829  * to store the FLOGI service parameters, so fc_host_attr must be
830  * initialized before calling this handler.
831  */
832 int fc_fabric_login(struct fc_lport *lp);
833 
834 /*
835  * The link is up for the given local port.
836  */
837 void fc_linkup(struct fc_lport *);
838 
839 /*
840  * Link is down for the given local port.
841  */
842 void fc_linkdown(struct fc_lport *);
843 
844 /*
845  * Configure the local port.
846  */
847 int fc_lport_config(struct fc_lport *);
848 
849 /*
850  * Reset the local port.
851  */
852 int fc_lport_reset(struct fc_lport *);
853 
854 /*
855  * Set the mfs or reset
856  */
857 int fc_set_mfs(struct fc_lport *lp, u32 mfs);
858 
859 
860 /*
861  * REMOTE PORT LAYER
862  *****************************/
863 int fc_rport_init(struct fc_lport *lp);
864 void fc_rport_terminate_io(struct fc_rport *rp);
865 
866 /*
867  * DISCOVERY LAYER
868  *****************************/
869 int fc_disc_init(struct fc_lport *lp);
870 
871 
872 /*
873  * SCSI LAYER
874  *****************************/
875 /*
876  * Initialize the SCSI block of libfc
877  */
878 int fc_fcp_init(struct fc_lport *);
879 
880 /*
881  * This section provides an API which allows direct interaction
882  * with the SCSI-ml. Each of these functions satisfies a function
883  * pointer defined in Scsi_Host and therefore is always called
884  * directly from the SCSI-ml.
885  */
886 int fc_queuecommand(struct scsi_cmnd *sc_cmd,
887 		    void (*done)(struct scsi_cmnd *));
888 
889 /*
890  * complete processing of a fcp packet
891  *
892  * This function may sleep if a fsp timer is pending.
893  * The host lock must not be held by caller.
894  */
895 void fc_fcp_complete(struct fc_fcp_pkt *fsp);
896 
897 /*
898  * Send an ABTS frame to the target device. The sc_cmd argument
899  * is a pointer to the SCSI command to be aborted.
900  */
901 int fc_eh_abort(struct scsi_cmnd *sc_cmd);
902 
903 /*
904  * Reset a LUN by sending send the tm cmd to the target.
905  */
906 int fc_eh_device_reset(struct scsi_cmnd *sc_cmd);
907 
908 /*
909  * Reset the host adapter.
910  */
911 int fc_eh_host_reset(struct scsi_cmnd *sc_cmd);
912 
913 /*
914  * Check rport status.
915  */
916 int fc_slave_alloc(struct scsi_device *sdev);
917 
918 /*
919  * Adjust the queue depth.
920  */
921 int fc_change_queue_depth(struct scsi_device *sdev, int qdepth);
922 
923 /*
924  * Change the tag type.
925  */
926 int fc_change_queue_type(struct scsi_device *sdev, int tag_type);
927 
928 /*
929  * Free memory pools used by the FCP layer.
930  */
931 void fc_fcp_destroy(struct fc_lport *);
932 
933 /*
934  * Set up direct-data placement for this I/O request
935  */
936 void fc_fcp_ddp_setup(struct fc_fcp_pkt *fsp, u16 xid);
937 
938 /*
939  * ELS/CT interface
940  *****************************/
941 /*
942  * Initializes ELS/CT interface
943  */
944 int fc_elsct_init(struct fc_lport *lp);
945 
946 
947 /*
948  * EXCHANGE MANAGER LAYER
949  *****************************/
950 /*
951  * Initializes Exchange Manager related
952  * function pointers in struct libfc_function_template.
953  */
954 int fc_exch_init(struct fc_lport *lp);
955 
956 /*
957  * Adds Exchange Manager (EM) mp to lport.
958  *
959  * Adds specified mp to lport using struct fc_exch_mgr_anchor,
960  * the struct fc_exch_mgr_anchor allows same EM sharing by
961  * more than one lport with their specified match function,
962  * the match function is used in allocating exchange from
963  * added mp.
964  */
965 struct fc_exch_mgr_anchor *fc_exch_mgr_add(struct fc_lport *lport,
966 					   struct fc_exch_mgr *mp,
967 					   bool (*match)(struct fc_frame *));
968 
969 /*
970  * Deletes Exchange Manager (EM) from lport by removing
971  * its anchor ema from lport.
972  *
973  * If removed anchor ema was the last user of its associated EM
974  * then also destroys associated EM.
975  */
976 void fc_exch_mgr_del(struct fc_exch_mgr_anchor *ema);
977 
978 /*
979  * Allocates an Exchange Manager (EM).
980  *
981  * The EM manages exchanges for their allocation and
982  * free, also allows exchange lookup for received
983  * frame.
984  *
985  * The class is used for initializing FC class of
986  * allocated exchange from EM.
987  *
988  * The min_xid and max_xid will limit new
989  * exchange ID (XID) within this range for
990  * a new exchange.
991  * The LLD may choose to have multiple EMs,
992  * e.g. one EM instance per CPU receive thread in LLD.
993  *
994  * Specified match function is used in allocating exchanges
995  * from newly allocated EM.
996  */
997 struct fc_exch_mgr *fc_exch_mgr_alloc(struct fc_lport *lp,
998 				      enum fc_class class,
999 				      u16 min_xid,
1000 				      u16 max_xid,
1001 				      bool (*match)(struct fc_frame *));
1002 
1003 /*
1004  * Free all exchange managers of a lport.
1005  */
1006 void fc_exch_mgr_free(struct fc_lport *lport);
1007 
1008 /*
1009  * Receive a frame on specified local port and exchange manager.
1010  */
1011 void fc_exch_recv(struct fc_lport *lp, struct fc_frame *fp);
1012 
1013 /*
1014  * This function is for exch_seq_send function pointer in
1015  * struct libfc_function_template, see comment block on
1016  * exch_seq_send for description of this function.
1017  */
1018 struct fc_seq *fc_exch_seq_send(struct fc_lport *lp,
1019 				struct fc_frame *fp,
1020 				void (*resp)(struct fc_seq *sp,
1021 					     struct fc_frame *fp,
1022 					     void *arg),
1023 				void (*destructor)(struct fc_seq *sp,
1024 						   void *arg),
1025 				void *arg, u32 timer_msec);
1026 
1027 /*
1028  * send a frame using existing sequence and exchange.
1029  */
1030 int fc_seq_send(struct fc_lport *lp, struct fc_seq *sp, struct fc_frame *fp);
1031 
1032 /*
1033  * Send ELS response using mainly infomation
1034  * in exchange and sequence in EM layer.
1035  */
1036 void fc_seq_els_rsp_send(struct fc_seq *sp, enum fc_els_cmd els_cmd,
1037 			 struct fc_seq_els_data *els_data);
1038 
1039 /*
1040  * This function is for seq_exch_abort function pointer in
1041  * struct libfc_function_template, see comment block on
1042  * seq_exch_abort for description of this function.
1043  */
1044 int fc_seq_exch_abort(const struct fc_seq *req_sp, unsigned int timer_msec);
1045 
1046 /*
1047  * Indicate that an exchange/sequence tuple is complete and the memory
1048  * allocated for the related objects may be freed.
1049  */
1050 void fc_exch_done(struct fc_seq *sp);
1051 
1052 /*
1053  * Allocate a new exchange and sequence pair.
1054  */
1055 struct fc_exch *fc_exch_alloc(struct fc_lport *lport, struct fc_frame *fp);
1056 /*
1057  * Start a new sequence on the same exchange as the supplied sequence.
1058  */
1059 struct fc_seq *fc_seq_start_next(struct fc_seq *sp);
1060 
1061 
1062 /*
1063  * Reset all EMs of a lport, releasing its all sequences and
1064  * exchanges. If sid is non-zero, then reset only exchanges
1065  * we sourced from that FID. If did is non-zero, reset only
1066  * exchanges destined to that FID.
1067  */
1068 void fc_exch_mgr_reset(struct fc_lport *, u32 s_id, u32 d_id);
1069 
1070 /*
1071  * Functions for fc_functions_template
1072  */
1073 void fc_get_host_speed(struct Scsi_Host *shost);
1074 void fc_get_host_port_type(struct Scsi_Host *shost);
1075 void fc_get_host_port_state(struct Scsi_Host *shost);
1076 void fc_set_rport_loss_tmo(struct fc_rport *rport, u32 timeout);
1077 struct fc_host_statistics *fc_get_host_stats(struct Scsi_Host *);
1078 
1079 /*
1080  * module setup functions.
1081  */
1082 int fc_setup_exch_mgr(void);
1083 void fc_destroy_exch_mgr(void);
1084 int fc_setup_rport(void);
1085 void fc_destroy_rport(void);
1086 
1087 /*
1088  * Internal libfc functions.
1089  */
1090 const char *fc_els_resp_type(struct fc_frame *);
1091 
1092 #endif /* _LIBFC_H_ */
1093