xref: /openbmc/linux/include/scsi/libfc.h (revision 9e9d0452)
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  * @ids: identifiers structure to pass to fc_remote_port_add()
154  * @rport_work: work struct for starting the rport state machine
155  */
156 struct fc_disc_port {
157 	struct fc_lport             *lp;
158 	struct list_head            peers;
159 	struct fc_rport_identifiers ids;
160 	struct work_struct	    rport_work;
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  * @maxframe_size: maximum frame size
206  * @retries: retry count in current state
207  * @e_d_tov: error detect timeout value (in msec)
208  * @r_a_tov: resource allocation timeout value (in msec)
209  * @rp_mutex: mutex protects rport
210  * @retry_work:
211  * @event_callback: Callback for rport READY, FAILED or LOGO
212  */
213 struct fc_rport_priv {
214 	struct fc_lport		   *local_port;
215 	struct fc_rport		   *rport;
216 	struct kref		   kref;
217 	enum fc_rport_state        rp_state;
218 	struct fc_rport_identifiers ids;
219 	u16			   flags;
220 	u16		           max_seq;
221 	u16			   maxframe_size;
222 	unsigned int	           retries;
223 	unsigned int	           e_d_tov;
224 	unsigned int	           r_a_tov;
225 	struct mutex               rp_mutex;
226 	struct delayed_work	   retry_work;
227 	enum fc_rport_event        event;
228 	struct fc_rport_operations *ops;
229 	struct list_head           peers;
230 	struct work_struct         event_work;
231 	u32			   supported_classes;
232 };
233 
234 /*
235  * fcoe stats structure
236  */
237 struct fcoe_dev_stats {
238 	u64		SecondsSinceLastReset;
239 	u64		TxFrames;
240 	u64		TxWords;
241 	u64		RxFrames;
242 	u64		RxWords;
243 	u64		ErrorFrames;
244 	u64		DumpedFrames;
245 	u64		LinkFailureCount;
246 	u64		LossOfSignalCount;
247 	u64		InvalidTxWordCount;
248 	u64		InvalidCRCCount;
249 	u64		InputRequests;
250 	u64		OutputRequests;
251 	u64		ControlRequests;
252 	u64		InputMegabytes;
253 	u64		OutputMegabytes;
254 };
255 
256 /*
257  * els data is used for passing ELS respone specific
258  * data to send ELS response mainly using infomation
259  * in exchange and sequence in EM layer.
260  */
261 struct fc_seq_els_data {
262 	struct fc_frame *fp;
263 	enum fc_els_rjt_reason reason;
264 	enum fc_els_rjt_explan explan;
265 };
266 
267 /*
268  * FCP request structure, one for each scsi cmd request
269  */
270 struct fc_fcp_pkt {
271 	/*
272 	 * housekeeping stuff
273 	 */
274 	struct fc_lport *lp;	/* handle to hba struct */
275 	u16		state;		/* scsi_pkt state state */
276 	u16		tgt_flags;	/* target flags	 */
277 	atomic_t	ref_cnt;	/* fcp pkt ref count */
278 	spinlock_t	scsi_pkt_lock;	/* Must be taken before the host lock
279 					 * if both are held at the same time */
280 	/*
281 	 * SCSI I/O related stuff
282 	 */
283 	struct scsi_cmnd *cmd;		/* scsi command pointer. set/clear
284 					 * under host lock */
285 	struct list_head list;		/* tracks queued commands. access under
286 					 * host lock */
287 	/*
288 	 * timeout related stuff
289 	 */
290 	struct timer_list timer;	/* command timer */
291 	struct completion tm_done;
292 	int	wait_for_comp;
293 	unsigned long	start_time;	/* start jiffie */
294 	unsigned long	end_time;	/* end jiffie */
295 	unsigned long	last_pkt_time;	 /* jiffies of last frame received */
296 
297 	/*
298 	 * scsi cmd and data transfer information
299 	 */
300 	u32		data_len;
301 	/*
302 	 * transport related veriables
303 	 */
304 	struct fcp_cmnd cdb_cmd;
305 	size_t		xfer_len;
306 	u16		xfer_ddp;	/* this xfer is ddped */
307 	u32		xfer_contig_end; /* offset of end of contiguous xfer */
308 	u16		max_payload;	/* max payload size in bytes */
309 
310 	/*
311 	 * scsi/fcp return status
312 	 */
313 	u32		io_status;	/* SCSI result upper 24 bits */
314 	u8		cdb_status;
315 	u8		status_code;	/* FCP I/O status */
316 	/* bit 3 Underrun bit 2: overrun */
317 	u8		scsi_comp_flags;
318 	u32		req_flags;	/* bit 0: read bit:1 write */
319 	u32		scsi_resid;	/* residule length */
320 
321 	struct fc_rport	*rport;		/* remote port pointer */
322 	struct fc_seq	*seq_ptr;	/* current sequence pointer */
323 	/*
324 	 * Error Processing
325 	 */
326 	u8		recov_retry;	/* count of recovery retries */
327 	struct fc_seq	*recov_seq;	/* sequence for REC or SRR */
328 };
329 /*
330  * FC_FCP HELPER FUNCTIONS
331  *****************************/
332 static inline bool fc_fcp_is_read(const struct fc_fcp_pkt *fsp)
333 {
334 	if (fsp && fsp->cmd)
335 		return fsp->cmd->sc_data_direction == DMA_FROM_DEVICE;
336 	return false;
337 }
338 
339 /*
340  * Structure and function definitions for managing Fibre Channel Exchanges
341  * and Sequences
342  *
343  * fc_exch holds state for one exchange and links to its active sequence.
344  *
345  * fc_seq holds the state for an individual sequence.
346  */
347 
348 struct fc_exch_mgr;
349 struct fc_exch_mgr_anchor;
350 extern u16	fc_cpu_mask;	/* cpu mask for possible cpus */
351 
352 /*
353  * Sequence.
354  */
355 struct fc_seq {
356 	u8	id;		/* seq ID */
357 	u16	ssb_stat;	/* status flags for sequence status block */
358 	u16	cnt;		/* frames sent so far on sequence */
359 	u32	rec_data;	/* FC-4 value for REC */
360 };
361 
362 #define FC_EX_DONE		(1 << 0) /* ep is completed */
363 #define FC_EX_RST_CLEANUP	(1 << 1) /* reset is forcing completion */
364 
365 /*
366  * Exchange.
367  *
368  * Locking notes: The ex_lock protects following items:
369  *	state, esb_stat, f_ctl, seq.ssb_stat
370  *	seq_id
371  *	sequence allocation
372  */
373 struct fc_exch {
374 	struct fc_exch_mgr *em;		/* exchange manager */
375 	struct fc_exch_pool *pool;	/* per cpu exches pool */
376 	u32		state;		/* internal driver state */
377 	u16		xid;		/* our exchange ID */
378 	struct list_head	ex_list;	/* free or busy list linkage */
379 	spinlock_t	ex_lock;	/* lock covering exchange state */
380 	atomic_t	ex_refcnt;	/* reference counter */
381 	struct delayed_work timeout_work; /* timer for upper level protocols */
382 	struct fc_lport	*lp;		/* fc device instance */
383 	u16		oxid;		/* originator's exchange ID */
384 	u16		rxid;		/* responder's exchange ID */
385 	u32		oid;		/* originator's FCID */
386 	u32		sid;		/* source FCID */
387 	u32		did;		/* destination FCID */
388 	u32		esb_stat;	/* exchange status for ESB */
389 	u32		r_a_tov;	/* r_a_tov from rport (msec) */
390 	u8		seq_id;		/* next sequence ID to use */
391 	u32		f_ctl;		/* F_CTL flags for sequences */
392 	u8		fh_type;	/* frame type */
393 	enum fc_class	class;		/* class of service */
394 	struct fc_seq	seq;		/* single sequence */
395 	/*
396 	 * Handler for responses to this current exchange.
397 	 */
398 	void		(*resp)(struct fc_seq *, struct fc_frame *, void *);
399 	void		(*destructor)(struct fc_seq *, void *);
400 	/*
401 	 * arg is passed as void pointer to exchange
402 	 * resp and destructor handlers
403 	 */
404 	void		*arg;
405 };
406 #define	fc_seq_exch(sp) container_of(sp, struct fc_exch, seq)
407 
408 struct libfc_function_template {
409 
410 	/*
411 	 * Interface to send a FC frame
412 	 *
413 	 * STATUS: REQUIRED
414 	 */
415 	int (*frame_send)(struct fc_lport *lp, struct fc_frame *fp);
416 
417 	/*
418 	 * Interface to send ELS/CT frames
419 	 *
420 	 * STATUS: OPTIONAL
421 	 */
422 	struct fc_seq *(*elsct_send)(struct fc_lport *lport,
423 				     u32 did,
424 				     struct fc_frame *fp,
425 				     unsigned int op,
426 				     void (*resp)(struct fc_seq *,
427 					     struct fc_frame *fp,
428 					     void *arg),
429 				     void *arg, u32 timer_msec);
430 
431 	/*
432 	 * Send the FC frame payload using a new exchange and sequence.
433 	 *
434 	 * The frame pointer with some of the header's fields must be
435 	 * filled before calling exch_seq_send(), those fields are,
436 	 *
437 	 * - routing control
438 	 * - FC port did
439 	 * - FC port sid
440 	 * - FC header type
441 	 * - frame control
442 	 * - parameter or relative offset
443 	 *
444 	 * The exchange response handler is set in this routine to resp()
445 	 * function pointer. It can be called in two scenarios: if a timeout
446 	 * occurs or if a response frame is received for the exchange. The
447 	 * fc_frame pointer in response handler will also indicate timeout
448 	 * as error using IS_ERR related macros.
449 	 *
450 	 * The exchange destructor handler is also set in this routine.
451 	 * The destructor handler is invoked by EM layer when exchange
452 	 * is about to free, this can be used by caller to free its
453 	 * resources along with exchange free.
454 	 *
455 	 * The arg is passed back to resp and destructor handler.
456 	 *
457 	 * The timeout value (in msec) for an exchange is set if non zero
458 	 * timer_msec argument is specified. The timer is canceled when
459 	 * it fires or when the exchange is done. The exchange timeout handler
460 	 * is registered by EM layer.
461 	 *
462 	 * STATUS: OPTIONAL
463 	 */
464 	struct fc_seq *(*exch_seq_send)(struct fc_lport *lp,
465 					struct fc_frame *fp,
466 					void (*resp)(struct fc_seq *sp,
467 						     struct fc_frame *fp,
468 						     void *arg),
469 					void (*destructor)(struct fc_seq *sp,
470 							   void *arg),
471 					void *arg, unsigned int timer_msec);
472 
473 	/*
474 	 * Sets up the DDP context for a given exchange id on the given
475 	 * scatterlist if LLD supports DDP for large receive.
476 	 *
477 	 * STATUS: OPTIONAL
478 	 */
479 	int (*ddp_setup)(struct fc_lport *lp, u16 xid,
480 			 struct scatterlist *sgl, unsigned int sgc);
481 	/*
482 	 * Completes the DDP transfer and returns the length of data DDPed
483 	 * for the given exchange id.
484 	 *
485 	 * STATUS: OPTIONAL
486 	 */
487 	int (*ddp_done)(struct fc_lport *lp, u16 xid);
488 	/*
489 	 * Send a frame using an existing sequence and exchange.
490 	 *
491 	 * STATUS: OPTIONAL
492 	 */
493 	int (*seq_send)(struct fc_lport *lp, struct fc_seq *sp,
494 			struct fc_frame *fp);
495 
496 	/*
497 	 * Send an ELS response using infomation from a previous
498 	 * exchange and sequence.
499 	 *
500 	 * STATUS: OPTIONAL
501 	 */
502 	void (*seq_els_rsp_send)(struct fc_seq *sp, enum fc_els_cmd els_cmd,
503 				 struct fc_seq_els_data *els_data);
504 
505 	/*
506 	 * Abort an exchange and sequence. Generally called because of a
507 	 * exchange timeout or an abort from the upper layer.
508 	 *
509 	 * A timer_msec can be specified for abort timeout, if non-zero
510 	 * timer_msec value is specified then exchange resp handler
511 	 * will be called with timeout error if no response to abort.
512 	 *
513 	 * STATUS: OPTIONAL
514 	 */
515 	int (*seq_exch_abort)(const struct fc_seq *req_sp,
516 			      unsigned int timer_msec);
517 
518 	/*
519 	 * Indicate that an exchange/sequence tuple is complete and the memory
520 	 * allocated for the related objects may be freed.
521 	 *
522 	 * STATUS: OPTIONAL
523 	 */
524 	void (*exch_done)(struct fc_seq *sp);
525 
526 	/*
527 	 * Start a new sequence on the same exchange/sequence tuple.
528 	 *
529 	 * STATUS: OPTIONAL
530 	 */
531 	struct fc_seq *(*seq_start_next)(struct fc_seq *sp);
532 
533 	/*
534 	 * Reset an exchange manager, completing all sequences and exchanges.
535 	 * If s_id is non-zero, reset only exchanges originating from that FID.
536 	 * If d_id is non-zero, reset only exchanges sending to that FID.
537 	 *
538 	 * STATUS: OPTIONAL
539 	 */
540 	void (*exch_mgr_reset)(struct fc_lport *,
541 			       u32 s_id, u32 d_id);
542 
543 	/*
544 	 * Flush the rport work queue. Generally used before shutdown.
545 	 *
546 	 * STATUS: OPTIONAL
547 	 */
548 	void (*rport_flush_queue)(void);
549 
550 	/*
551 	 * Receive a frame for a local port.
552 	 *
553 	 * STATUS: OPTIONAL
554 	 */
555 	void (*lport_recv)(struct fc_lport *lp, struct fc_seq *sp,
556 			   struct fc_frame *fp);
557 
558 	/*
559 	 * Reset the local port.
560 	 *
561 	 * STATUS: OPTIONAL
562 	 */
563 	int (*lport_reset)(struct fc_lport *);
564 
565 	/*
566 	 * Create a remote port
567 	 */
568 	struct fc_rport_priv *(*rport_create)(struct fc_lport *,
569 					      struct fc_rport_identifiers *);
570 
571 	/*
572 	 * Initiates the RP state machine. It is called from the LP module.
573 	 * This function will issue the following commands to the N_Port
574 	 * identified by the FC ID provided.
575 	 *
576 	 * - PLOGI
577 	 * - PRLI
578 	 * - RTV
579 	 *
580 	 * STATUS: OPTIONAL
581 	 */
582 	int (*rport_login)(struct fc_rport_priv *);
583 
584 	/*
585 	 * Logoff, and remove the rport from the transport if
586 	 * it had been added. This will send a LOGO to the target.
587 	 *
588 	 * STATUS: OPTIONAL
589 	 */
590 	int (*rport_logoff)(struct fc_rport_priv *);
591 
592 	/*
593 	 * Recieve a request from a remote port.
594 	 *
595 	 * STATUS: OPTIONAL
596 	 */
597 	void (*rport_recv_req)(struct fc_seq *, struct fc_frame *,
598 			       struct fc_rport_priv *);
599 
600 	/*
601 	 * lookup an rport by it's port ID.
602 	 *
603 	 * STATUS: OPTIONAL
604 	 */
605 	struct fc_rport_priv *(*rport_lookup)(const struct fc_lport *, u32);
606 
607 	/*
608 	 * Destroy an rport after final kref_put().
609 	 * The argument is a pointer to the kref inside the fc_rport_priv.
610 	 */
611 	void (*rport_destroy)(struct kref *);
612 
613 	/*
614 	 * Send a fcp cmd from fsp pkt.
615 	 * Called with the SCSI host lock unlocked and irqs disabled.
616 	 *
617 	 * The resp handler is called when FCP_RSP received.
618 	 *
619 	 * STATUS: OPTIONAL
620 	 */
621 	int (*fcp_cmd_send)(struct fc_lport *lp, struct fc_fcp_pkt *fsp,
622 			    void (*resp)(struct fc_seq *, struct fc_frame *fp,
623 					 void *arg));
624 
625 	/*
626 	 * Cleanup the FCP layer, used durring link down and reset
627 	 *
628 	 * STATUS: OPTIONAL
629 	 */
630 	void (*fcp_cleanup)(struct fc_lport *lp);
631 
632 	/*
633 	 * Abort all I/O on a local port
634 	 *
635 	 * STATUS: OPTIONAL
636 	 */
637 	void (*fcp_abort_io)(struct fc_lport *lp);
638 
639 	/*
640 	 * Receive a request for the discovery layer.
641 	 *
642 	 * STATUS: OPTIONAL
643 	 */
644 	void (*disc_recv_req)(struct fc_seq *,
645 			      struct fc_frame *, struct fc_lport *);
646 
647 	/*
648 	 * Start discovery for a local port.
649 	 *
650 	 * STATUS: OPTIONAL
651 	 */
652 	void (*disc_start)(void (*disc_callback)(struct fc_lport *,
653 						 enum fc_disc_event),
654 			   struct fc_lport *);
655 
656 	/*
657 	 * Stop discovery for a given lport. This will remove
658 	 * all discovered rports
659 	 *
660 	 * STATUS: OPTIONAL
661 	 */
662 	void (*disc_stop) (struct fc_lport *);
663 
664 	/*
665 	 * Stop discovery for a given lport. This will block
666 	 * until all discovered rports are deleted from the
667 	 * FC transport class
668 	 *
669 	 * STATUS: OPTIONAL
670 	 */
671 	void (*disc_stop_final) (struct fc_lport *);
672 };
673 
674 /* information used by the discovery layer */
675 struct fc_disc {
676 	unsigned char		retry_count;
677 	unsigned char		delay;
678 	unsigned char		pending;
679 	unsigned char		requested;
680 	unsigned short		seq_count;
681 	unsigned char		buf_len;
682 	enum fc_disc_event	event;
683 
684 	void (*disc_callback)(struct fc_lport *,
685 			      enum fc_disc_event);
686 
687 	struct list_head	 rports;
688 	struct fc_lport		*lport;
689 	struct mutex		disc_mutex;
690 	struct fc_gpn_ft_resp	partial_buf;	/* partial name buffer */
691 	struct delayed_work	disc_work;
692 };
693 
694 struct fc_lport {
695 	struct list_head list;
696 
697 	/* Associations */
698 	struct Scsi_Host	*host;
699 	struct list_head	ema_list;
700 	struct fc_rport_priv	*dns_rp;
701 	struct fc_rport_priv	*ptp_rp;
702 	void			*scsi_priv;
703 	struct fc_disc          disc;
704 
705 	/* Operational Information */
706 	struct libfc_function_template tt;
707 	u8			link_up;
708 	u8			qfull;
709 	enum fc_lport_state	state;
710 	unsigned long		boot_time;
711 
712 	struct fc_host_statistics host_stats;
713 	struct fcoe_dev_stats	*dev_stats;
714 
715 	u64			wwpn;
716 	u64			wwnn;
717 	u8			retry_count;
718 
719 	/* Capabilities */
720 	u32			sg_supp:1;	/* scatter gather supported */
721 	u32			seq_offload:1;	/* seq offload supported */
722 	u32			crc_offload:1;	/* crc offload supported */
723 	u32			lro_enabled:1;	/* large receive offload */
724 	u32			mfs;	        /* max FC payload size */
725 	unsigned int		service_params;
726 	unsigned int		e_d_tov;
727 	unsigned int		r_a_tov;
728 	u8			max_retry_count;
729 	u8			max_rport_retry_count;
730 	u16			link_speed;
731 	u16			link_supported_speeds;
732 	u16			lro_xid;	/* max xid for fcoe lro */
733 	unsigned int		lso_max;	/* max large send size */
734 	struct fc_ns_fts	fcts;	        /* FC-4 type masks */
735 	struct fc_els_rnid_gen	rnid_gen;	/* RNID information */
736 
737 	/* Semaphores */
738 	struct mutex lp_mutex;
739 
740 	/* Miscellaneous */
741 	struct delayed_work	retry_work;
742 	struct delayed_work	disc_work;
743 };
744 
745 /*
746  * FC_LPORT HELPER FUNCTIONS
747  *****************************/
748 static inline int fc_lport_test_ready(struct fc_lport *lp)
749 {
750 	return lp->state == LPORT_ST_READY;
751 }
752 
753 static inline void fc_set_wwnn(struct fc_lport *lp, u64 wwnn)
754 {
755 	lp->wwnn = wwnn;
756 }
757 
758 static inline void fc_set_wwpn(struct fc_lport *lp, u64 wwnn)
759 {
760 	lp->wwpn = wwnn;
761 }
762 
763 static inline void fc_lport_state_enter(struct fc_lport *lp,
764 					enum fc_lport_state state)
765 {
766 	if (state != lp->state)
767 		lp->retry_count = 0;
768 	lp->state = state;
769 }
770 
771 static inline int fc_lport_init_stats(struct fc_lport *lp)
772 {
773 	/* allocate per cpu stats block */
774 	lp->dev_stats = alloc_percpu(struct fcoe_dev_stats);
775 	if (!lp->dev_stats)
776 		return -ENOMEM;
777 	return 0;
778 }
779 
780 static inline void fc_lport_free_stats(struct fc_lport *lp)
781 {
782 	free_percpu(lp->dev_stats);
783 }
784 
785 static inline struct fcoe_dev_stats *fc_lport_get_stats(struct fc_lport *lp)
786 {
787 	return per_cpu_ptr(lp->dev_stats, smp_processor_id());
788 }
789 
790 static inline void *lport_priv(const struct fc_lport *lp)
791 {
792 	return (void *)(lp + 1);
793 }
794 
795 /**
796  * libfc_host_alloc() - Allocate a Scsi_Host with room for the fc_lport
797  * @sht: ptr to the scsi host templ
798  * @priv_size: size of private data after fc_lport
799  *
800  * Returns: ptr to Scsi_Host
801  */
802 static inline struct Scsi_Host *
803 libfc_host_alloc(struct scsi_host_template *sht, int priv_size)
804 {
805 	return scsi_host_alloc(sht, sizeof(struct fc_lport) + priv_size);
806 }
807 
808 /*
809  * LOCAL PORT LAYER
810  *****************************/
811 int fc_lport_init(struct fc_lport *lp);
812 
813 /*
814  * Destroy the specified local port by finding and freeing all
815  * fc_rports associated with it and then by freeing the fc_lport
816  * itself.
817  */
818 int fc_lport_destroy(struct fc_lport *lp);
819 
820 /*
821  * Logout the specified local port from the fabric
822  */
823 int fc_fabric_logoff(struct fc_lport *lp);
824 
825 /*
826  * Initiate the LP state machine. This handler will use fc_host_attr
827  * to store the FLOGI service parameters, so fc_host_attr must be
828  * initialized before calling this handler.
829  */
830 int fc_fabric_login(struct fc_lport *lp);
831 
832 /*
833  * The link is up for the given local port.
834  */
835 void fc_linkup(struct fc_lport *);
836 
837 /*
838  * Link is down for the given local port.
839  */
840 void fc_linkdown(struct fc_lport *);
841 
842 /*
843  * Configure the local port.
844  */
845 int fc_lport_config(struct fc_lport *);
846 
847 /*
848  * Reset the local port.
849  */
850 int fc_lport_reset(struct fc_lport *);
851 
852 /*
853  * Set the mfs or reset
854  */
855 int fc_set_mfs(struct fc_lport *lp, u32 mfs);
856 
857 
858 /*
859  * REMOTE PORT LAYER
860  *****************************/
861 int fc_rport_init(struct fc_lport *lp);
862 void fc_rport_terminate_io(struct fc_rport *rp);
863 
864 /*
865  * DISCOVERY LAYER
866  *****************************/
867 int fc_disc_init(struct fc_lport *lp);
868 
869 
870 /*
871  * SCSI LAYER
872  *****************************/
873 /*
874  * Initialize the SCSI block of libfc
875  */
876 int fc_fcp_init(struct fc_lport *);
877 
878 /*
879  * This section provides an API which allows direct interaction
880  * with the SCSI-ml. Each of these functions satisfies a function
881  * pointer defined in Scsi_Host and therefore is always called
882  * directly from the SCSI-ml.
883  */
884 int fc_queuecommand(struct scsi_cmnd *sc_cmd,
885 		    void (*done)(struct scsi_cmnd *));
886 
887 /*
888  * complete processing of a fcp packet
889  *
890  * This function may sleep if a fsp timer is pending.
891  * The host lock must not be held by caller.
892  */
893 void fc_fcp_complete(struct fc_fcp_pkt *fsp);
894 
895 /*
896  * Send an ABTS frame to the target device. The sc_cmd argument
897  * is a pointer to the SCSI command to be aborted.
898  */
899 int fc_eh_abort(struct scsi_cmnd *sc_cmd);
900 
901 /*
902  * Reset a LUN by sending send the tm cmd to the target.
903  */
904 int fc_eh_device_reset(struct scsi_cmnd *sc_cmd);
905 
906 /*
907  * Reset the host adapter.
908  */
909 int fc_eh_host_reset(struct scsi_cmnd *sc_cmd);
910 
911 /*
912  * Check rport status.
913  */
914 int fc_slave_alloc(struct scsi_device *sdev);
915 
916 /*
917  * Adjust the queue depth.
918  */
919 int fc_change_queue_depth(struct scsi_device *sdev, int qdepth);
920 
921 /*
922  * Change the tag type.
923  */
924 int fc_change_queue_type(struct scsi_device *sdev, int tag_type);
925 
926 /*
927  * Free memory pools used by the FCP layer.
928  */
929 void fc_fcp_destroy(struct fc_lport *);
930 
931 /*
932  * Set up direct-data placement for this I/O request
933  */
934 void fc_fcp_ddp_setup(struct fc_fcp_pkt *fsp, u16 xid);
935 
936 /*
937  * ELS/CT interface
938  *****************************/
939 /*
940  * Initializes ELS/CT interface
941  */
942 int fc_elsct_init(struct fc_lport *lp);
943 
944 
945 /*
946  * EXCHANGE MANAGER LAYER
947  *****************************/
948 /*
949  * Initializes Exchange Manager related
950  * function pointers in struct libfc_function_template.
951  */
952 int fc_exch_init(struct fc_lport *lp);
953 
954 /*
955  * Adds Exchange Manager (EM) mp to lport.
956  *
957  * Adds specified mp to lport using struct fc_exch_mgr_anchor,
958  * the struct fc_exch_mgr_anchor allows same EM sharing by
959  * more than one lport with their specified match function,
960  * the match function is used in allocating exchange from
961  * added mp.
962  */
963 struct fc_exch_mgr_anchor *fc_exch_mgr_add(struct fc_lport *lport,
964 					   struct fc_exch_mgr *mp,
965 					   bool (*match)(struct fc_frame *));
966 
967 /*
968  * Deletes Exchange Manager (EM) from lport by removing
969  * its anchor ema from lport.
970  *
971  * If removed anchor ema was the last user of its associated EM
972  * then also destroys associated EM.
973  */
974 void fc_exch_mgr_del(struct fc_exch_mgr_anchor *ema);
975 
976 /*
977  * Allocates an Exchange Manager (EM).
978  *
979  * The EM manages exchanges for their allocation and
980  * free, also allows exchange lookup for received
981  * frame.
982  *
983  * The class is used for initializing FC class of
984  * allocated exchange from EM.
985  *
986  * The min_xid and max_xid will limit new
987  * exchange ID (XID) within this range for
988  * a new exchange.
989  * The LLD may choose to have multiple EMs,
990  * e.g. one EM instance per CPU receive thread in LLD.
991  *
992  * Specified match function is used in allocating exchanges
993  * from newly allocated EM.
994  */
995 struct fc_exch_mgr *fc_exch_mgr_alloc(struct fc_lport *lp,
996 				      enum fc_class class,
997 				      u16 min_xid,
998 				      u16 max_xid,
999 				      bool (*match)(struct fc_frame *));
1000 
1001 /*
1002  * Free all exchange managers of a lport.
1003  */
1004 void fc_exch_mgr_free(struct fc_lport *lport);
1005 
1006 /*
1007  * Receive a frame on specified local port and exchange manager.
1008  */
1009 void fc_exch_recv(struct fc_lport *lp, struct fc_frame *fp);
1010 
1011 /*
1012  * This function is for exch_seq_send function pointer in
1013  * struct libfc_function_template, see comment block on
1014  * exch_seq_send for description of this function.
1015  */
1016 struct fc_seq *fc_exch_seq_send(struct fc_lport *lp,
1017 				struct fc_frame *fp,
1018 				void (*resp)(struct fc_seq *sp,
1019 					     struct fc_frame *fp,
1020 					     void *arg),
1021 				void (*destructor)(struct fc_seq *sp,
1022 						   void *arg),
1023 				void *arg, u32 timer_msec);
1024 
1025 /*
1026  * send a frame using existing sequence and exchange.
1027  */
1028 int fc_seq_send(struct fc_lport *lp, struct fc_seq *sp, struct fc_frame *fp);
1029 
1030 /*
1031  * Send ELS response using mainly infomation
1032  * in exchange and sequence in EM layer.
1033  */
1034 void fc_seq_els_rsp_send(struct fc_seq *sp, enum fc_els_cmd els_cmd,
1035 			 struct fc_seq_els_data *els_data);
1036 
1037 /*
1038  * This function is for seq_exch_abort function pointer in
1039  * struct libfc_function_template, see comment block on
1040  * seq_exch_abort for description of this function.
1041  */
1042 int fc_seq_exch_abort(const struct fc_seq *req_sp, unsigned int timer_msec);
1043 
1044 /*
1045  * Indicate that an exchange/sequence tuple is complete and the memory
1046  * allocated for the related objects may be freed.
1047  */
1048 void fc_exch_done(struct fc_seq *sp);
1049 
1050 /*
1051  * Allocate a new exchange and sequence pair.
1052  */
1053 struct fc_exch *fc_exch_alloc(struct fc_lport *lport, struct fc_frame *fp);
1054 /*
1055  * Start a new sequence on the same exchange as the supplied sequence.
1056  */
1057 struct fc_seq *fc_seq_start_next(struct fc_seq *sp);
1058 
1059 
1060 /*
1061  * Reset all EMs of a lport, releasing its all sequences and
1062  * exchanges. If sid is non-zero, then reset only exchanges
1063  * we sourced from that FID. If did is non-zero, reset only
1064  * exchanges destined to that FID.
1065  */
1066 void fc_exch_mgr_reset(struct fc_lport *, u32 s_id, u32 d_id);
1067 
1068 /*
1069  * Functions for fc_functions_template
1070  */
1071 void fc_get_host_speed(struct Scsi_Host *shost);
1072 void fc_get_host_port_type(struct Scsi_Host *shost);
1073 void fc_get_host_port_state(struct Scsi_Host *shost);
1074 void fc_set_rport_loss_tmo(struct fc_rport *rport, u32 timeout);
1075 struct fc_host_statistics *fc_get_host_stats(struct Scsi_Host *);
1076 
1077 /*
1078  * module setup functions.
1079  */
1080 int fc_setup_exch_mgr(void);
1081 void fc_destroy_exch_mgr(void);
1082 int fc_setup_rport(void);
1083 void fc_destroy_rport(void);
1084 
1085 #endif /* _LIBFC_H_ */
1086