xref: /linux/include/scsi/libfc.h (revision 0526b56cbc3c489642bd6a5fe4b718dea7ef0ee8)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright(c) 2007 Intel Corporation. All rights reserved.
4  *
5  * Maintained at www.Open-FCoE.org
6  */
7 
8 #ifndef _LIBFC_H_
9 #define _LIBFC_H_
10 
11 #include <linux/timer.h>
12 #include <linux/if.h>
13 #include <linux/percpu.h>
14 #include <linux/refcount.h>
15 
16 #include <scsi/scsi_transport.h>
17 #include <scsi/scsi_transport_fc.h>
18 #include <scsi/scsi_bsg_fc.h>
19 
20 #include <scsi/fc/fc_fcp.h>
21 #include <scsi/fc/fc_ns.h>
22 #include <scsi/fc/fc_ms.h>
23 #include <scsi/fc/fc_els.h>
24 #include <scsi/fc/fc_gs.h>
25 
26 #include <scsi/fc_frame.h>
27 
28 #define	FC_FC4_PROV_SIZE	(FC_TYPE_FCP + 1)	/* size of tables */
29 
30 /*
31  * libfc error codes
32  */
33 #define	FC_NO_ERR	0	/* no error */
34 #define	FC_EX_TIMEOUT	1	/* Exchange timeout */
35 #define	FC_EX_CLOSED	2	/* Exchange closed */
36 #define FC_EX_ALLOC_ERR	3	/* Exchange allocation failed */
37 #define FC_EX_XMIT_ERR	4	/* Exchange transmit failed */
38 #define FC_EX_ELS_RJT	5	/* ELS rejected */
39 #define FC_EX_INV_LOGIN	6	/* Login not completed */
40 #define FC_EX_SEQ_ERR	6	/* Exchange sequence error */
41 
42 /**
43  * enum fc_lport_state - Local port states
44  * @LPORT_ST_DISABLED: Disabled
45  * @LPORT_ST_FLOGI:    Fabric login (FLOGI) sent
46  * @LPORT_ST_DNS:      Waiting for name server remote port to become ready
47  * @LPORT_ST_RPN_ID:   Register port name by ID (RPN_ID) sent
48  * @LPORT_ST_RFT_ID:   Register Fibre Channel types by ID (RFT_ID) sent
49  * @LPORT_ST_RFF_ID:   Register FC-4 Features by ID (RFF_ID) sent
50  * @LPORT_ST_FDMI:     Waiting for mgmt server rport to become ready
51  * @LPORT_ST_RHBA:
52  * @LPORT_ST_SCR:      State Change Register (SCR) sent
53  * @LPORT_ST_READY:    Ready for use
54  * @LPORT_ST_LOGO:     Local port logout (LOGO) sent
55  * @LPORT_ST_RESET:    Local port reset
56  */
57 enum fc_lport_state {
58 	LPORT_ST_DISABLED = 0,
59 	LPORT_ST_FLOGI,
60 	LPORT_ST_DNS,
61 	LPORT_ST_RNN_ID,
62 	LPORT_ST_RSNN_NN,
63 	LPORT_ST_RSPN_ID,
64 	LPORT_ST_RFT_ID,
65 	LPORT_ST_RFF_ID,
66 	LPORT_ST_FDMI,
67 	LPORT_ST_RHBA,
68 	LPORT_ST_RPA,
69 	LPORT_ST_DHBA,
70 	LPORT_ST_DPRT,
71 	LPORT_ST_SCR,
72 	LPORT_ST_READY,
73 	LPORT_ST_LOGO,
74 	LPORT_ST_RESET
75 };
76 
77 enum fc_disc_event {
78 	DISC_EV_NONE = 0,
79 	DISC_EV_SUCCESS,
80 	DISC_EV_FAILED
81 };
82 
83 /**
84  * enum fc_rport_state - Remote port states
85  * @RPORT_ST_INIT:    Initialized
86  * @RPORT_ST_FLOGI:   Waiting for FLOGI completion for point-to-multipoint
87  * @RPORT_ST_PLOGI_WAIT:   Waiting for peer to login for point-to-multipoint
88  * @RPORT_ST_PLOGI:   Waiting for PLOGI completion
89  * @RPORT_ST_PRLI:    Waiting for PRLI completion
90  * @RPORT_ST_RTV:     Waiting for RTV completion
91  * @RPORT_ST_READY:   Ready for use
92  * @RPORT_ST_ADISC:   Discover Address sent
93  * @RPORT_ST_DELETE:  Remote port being deleted
94 */
95 enum fc_rport_state {
96 	RPORT_ST_INIT,
97 	RPORT_ST_FLOGI,
98 	RPORT_ST_PLOGI_WAIT,
99 	RPORT_ST_PLOGI,
100 	RPORT_ST_PRLI,
101 	RPORT_ST_RTV,
102 	RPORT_ST_READY,
103 	RPORT_ST_ADISC,
104 	RPORT_ST_DELETE,
105 };
106 
107 /**
108  * struct fc_disc_port - temporary discovery port to hold rport identifiers
109  * @lp:         Fibre Channel host port instance
110  * @peers:      Node for list management during discovery and RSCN processing
111  * @rport_work: Work struct for starting the rport state machine
112  * @port_id:    Port ID of the discovered port
113  */
114 struct fc_disc_port {
115 	struct fc_lport    *lp;
116 	struct list_head   peers;
117 	struct work_struct rport_work;
118 	u32		   port_id;
119 };
120 
121 /**
122  * enum fc_rport_event - Remote port events
123  * @RPORT_EV_NONE:   No event
124  * @RPORT_EV_READY:  Remote port is ready for use
125  * @RPORT_EV_FAILED: State machine failed, remote port is not ready
126  * @RPORT_EV_STOP:   Remote port has been stopped
127  * @RPORT_EV_LOGO:   Remote port logout (LOGO) sent
128  */
129 enum fc_rport_event {
130 	RPORT_EV_NONE = 0,
131 	RPORT_EV_READY,
132 	RPORT_EV_FAILED,
133 	RPORT_EV_STOP,
134 	RPORT_EV_LOGO
135 };
136 
137 struct fc_rport_priv;
138 
139 /**
140  * struct fc_rport_operations - Operations for a remote port
141  * @event_callback: Function to be called for remote port events
142  */
143 struct fc_rport_operations {
144 	void (*event_callback)(struct fc_lport *, struct fc_rport_priv *,
145 			       enum fc_rport_event);
146 };
147 
148 /**
149  * struct fc_rport_libfc_priv - libfc internal information about a remote port
150  * @local_port: The associated local port
151  * @rp_state:   Indicates READY for I/O or DELETE when blocked
152  * @flags:      REC and RETRY supported flags
153  * @e_d_tov:    Error detect timeout value (in msec)
154  * @r_a_tov:    Resource allocation timeout value (in msec)
155  */
156 struct fc_rport_libfc_priv {
157 	struct fc_lport		   *local_port;
158 	enum fc_rport_state	   rp_state;
159 	u16			   flags;
160 	#define FC_RP_FLAGS_REC_SUPPORTED	(1 << 0)
161 	#define FC_RP_FLAGS_RETRY		(1 << 1)
162 	#define FC_RP_STARTED			(1 << 2)
163 	#define FC_RP_FLAGS_CONF_REQ		(1 << 3)
164 	unsigned int		   e_d_tov;
165 	unsigned int		   r_a_tov;
166 };
167 
168 /**
169  * struct fc_rport_priv - libfc remote port and discovery info
170  * @local_port:     The associated local port
171  * @rport:          The FC transport remote port
172  * @kref:           Reference counter
173  * @rp_state:       Enumeration that tracks progress of PLOGI, PRLI,
174  *                  and RTV exchanges
175  * @ids:            The remote port identifiers and roles
176  * @flags:          STARTED, REC and RETRY_SUPPORTED flags
177  * @max_seq:        Maximum number of concurrent sequences
178  * @disc_id:        The discovery identifier
179  * @maxframe_size:  The maximum frame size
180  * @retries:        The retry count for the current state
181  * @major_retries:  The retry count for the entire PLOGI/PRLI state machine
182  * @e_d_tov:        Error detect timeout value (in msec)
183  * @r_a_tov:        Resource allocation timeout value (in msec)
184  * @rp_mutex:       The mutex that protects the remote port
185  * @retry_work:     Handle for retries
186  * @event_callback: Callback when READY, FAILED or LOGO states complete
187  * @prli_count:     Count of open PRLI sessions in providers
188  * @rcu:	    Structure used for freeing in an RCU-safe manner
189  */
190 struct fc_rport_priv {
191 	struct fc_lport		    *local_port;
192 	struct fc_rport		    *rport;
193 	struct kref		    kref;
194 	enum fc_rport_state	    rp_state;
195 	struct fc_rport_identifiers ids;
196 	u16			    flags;
197 	u16			    max_seq;
198 	u16			    disc_id;
199 	u16			    maxframe_size;
200 	unsigned int		    retries;
201 	unsigned int		    major_retries;
202 	unsigned int		    e_d_tov;
203 	unsigned int		    r_a_tov;
204 	struct mutex		    rp_mutex;
205 	struct delayed_work	    retry_work;
206 	enum fc_rport_event	    event;
207 	struct fc_rport_operations  *ops;
208 	struct list_head	    peers;
209 	struct work_struct	    event_work;
210 	u32			    supported_classes;
211 	u16			    prli_count;
212 	struct rcu_head		    rcu;
213 	u16			    sp_features;
214 	u8			    spp_type;
215 	void			    (*lld_event_callback)(struct fc_lport *,
216 						      struct fc_rport_priv *,
217 						      enum fc_rport_event);
218 };
219 
220 /**
221  * struct fc_stats - fc stats structure
222  * @SecondsSinceLastReset: Seconds since the last reset
223  * @TxFrames:              Number of transmitted frames
224  * @TxWords:               Number of transmitted words
225  * @RxFrames:              Number of received frames
226  * @RxWords:               Number of received words
227  * @ErrorFrames:           Number of received error frames
228  * @DumpedFrames:          Number of dumped frames
229  * @FcpPktAllocFails:      Number of fcp packet allocation failures
230  * @FcpPktAborts:          Number of fcp packet aborts
231  * @FcpFrameAllocFails:    Number of fcp frame allocation failures
232  * @LinkFailureCount:      Number of link failures
233  * @LossOfSignalCount:     Number for signal losses
234  * @InvalidTxWordCount:    Number of invalid transmitted words
235  * @InvalidCRCCount:       Number of invalid CRCs
236  * @InputRequests:         Number of input requests
237  * @OutputRequests:        Number of output requests
238  * @ControlRequests:       Number of control requests
239  * @InputBytes:            Number of received bytes
240  * @OutputBytes:           Number of transmitted bytes
241  * @VLinkFailureCount:     Number of virtual link failures
242  * @MissDiscAdvCount:      Number of missing FIP discovery advertisement
243  */
244 struct fc_stats {
245 	u64		SecondsSinceLastReset;
246 	u64		TxFrames;
247 	u64		TxWords;
248 	u64		RxFrames;
249 	u64		RxWords;
250 	u64		ErrorFrames;
251 	u64		DumpedFrames;
252 	u64		FcpPktAllocFails;
253 	u64		FcpPktAborts;
254 	u64		FcpFrameAllocFails;
255 	u64		LinkFailureCount;
256 	u64		LossOfSignalCount;
257 	u64		InvalidTxWordCount;
258 	u64		InvalidCRCCount;
259 	u64		InputRequests;
260 	u64		OutputRequests;
261 	u64		ControlRequests;
262 	u64		InputBytes;
263 	u64		OutputBytes;
264 	u64		VLinkFailureCount;
265 	u64		MissDiscAdvCount;
266 };
267 
268 /**
269  * struct fc_seq_els_data - ELS data used for passing ELS specific responses
270  * @reason: The reason for rejection
271  * @explan: The explanation of the rejection
272  *
273  * Mainly used by the exchange manager layer.
274  */
275 struct fc_seq_els_data {
276 	enum fc_els_rjt_reason reason;
277 	enum fc_els_rjt_explan explan;
278 };
279 
280 /**
281  * struct fc_fcp_pkt - FCP request structure (one for each scsi_cmnd request)
282  * @lp:              The associated local port
283  * @state:           The state of the I/O
284  * @ref_cnt:         Reference count
285  * @scsi_pkt_lock:   Lock to protect the SCSI packet (must be taken before the
286  *                   host_lock if both are to be held at the same time)
287  * @cmd:             The SCSI command (set and clear with the host_lock held)
288  * @list:            Tracks queued commands (accessed with the host_lock held)
289  * @timer:           The command timer
290  * @tm_done:         Completion indicator
291  * @wait_for_comp:   Indicator to wait for completion of the I/O (in jiffies)
292  * @data_len:        The length of the data
293  * @cdb_cmd:         The CDB command
294  * @xfer_len:        The transfer length
295  * @xfer_ddp:        Indicates if this transfer used DDP (XID of the exchange
296  *                   will be set here if DDP was setup)
297  * @xfer_contig_end: The offset into the buffer if the buffer is contiguous
298  *                   (Tx and Rx)
299  * @max_payload:     The maximum payload size (in bytes)
300  * @io_status:       SCSI result (upper 24 bits)
301  * @cdb_status:      CDB status
302  * @status_code:     FCP I/O status
303  * @scsi_comp_flags: Completion flags (bit 3 Underrun bit 2: overrun)
304  * @req_flags:       Request flags (bit 0: read bit:1 write)
305  * @scsi_resid:      SCSI residule length
306  * @rport:           The remote port that the SCSI command is targeted at
307  * @seq_ptr:         The sequence that will carry the SCSI command
308  * @recov_retry:     Number of recovery retries
309  * @recov_seq:       The sequence for REC or SRR
310  */
311 struct fc_fcp_pkt {
312 	spinlock_t	  scsi_pkt_lock;
313 	refcount_t	  ref_cnt;
314 
315 	/* SCSI command and data transfer information */
316 	u32		  data_len;
317 
318 	/* SCSI I/O related information */
319 	struct scsi_cmnd  *cmd;
320 	struct list_head  list;
321 
322 	/* Housekeeping information */
323 	struct fc_lport   *lp;
324 	u8		  state;
325 
326 	/* SCSI/FCP return status */
327 	u8		  cdb_status;
328 	u8		  status_code;
329 	u8		  scsi_comp_flags;
330 	u32		  io_status;
331 	u32		  req_flags;
332 	u32		  scsi_resid;
333 
334 	/* Transport related veriables */
335 	size_t		  xfer_len;
336 	struct fcp_cmnd   cdb_cmd;
337 	u32		  xfer_contig_end;
338 	u16		  max_payload;
339 	u16		  xfer_ddp;
340 
341 	/* Associated structures */
342 	struct fc_rport	  *rport;
343 	struct fc_seq	  *seq_ptr;
344 
345 	/* Timeout/error related information */
346 	struct timer_list timer;
347 	int		  wait_for_comp;
348 	int		  timer_delay;
349 	u32		  recov_retry;
350 	struct fc_seq	  *recov_seq;
351 	struct completion tm_done;
352 } ____cacheline_aligned_in_smp;
353 
354 /*
355  * @fsp should be tested and set under the scsi_pkt_queue lock
356  */
357 struct libfc_cmd_priv {
358 	struct fc_fcp_pkt *fsp;
359 	u32 resid_len;
360 	u8 status;
361 };
362 
363 /*
364  * Structure and function definitions for managing Fibre Channel Exchanges
365  * and Sequences
366  *
367  * fc_exch holds state for one exchange and links to its active sequence.
368  *
369  * fc_seq holds the state for an individual sequence.
370  */
371 
372 struct fc_exch_mgr;
373 struct fc_exch_mgr_anchor;
374 extern u16 fc_cpu_mask;	/* cpu mask for possible cpus */
375 
376 /**
377  * struct fc_seq - FC sequence
378  * @id:       The sequence ID
379  * @ssb_stat: Status flags for the sequence status block (SSB)
380  * @cnt:      Number of frames sent so far
381  * @rec_data: FC-4 value for REC
382  */
383 struct fc_seq {
384 	u8  id;
385 	u16 ssb_stat;
386 	u16 cnt;
387 	u32 rec_data;
388 };
389 
390 #define FC_EX_DONE		(1 << 0) /* ep is completed */
391 #define FC_EX_RST_CLEANUP	(1 << 1) /* reset is forcing completion */
392 #define FC_EX_QUARANTINE	(1 << 2) /* exch is quarantined */
393 
394 /**
395  * struct fc_exch - Fibre Channel Exchange
396  * @em:           Exchange manager
397  * @pool:         Exchange pool
398  * @state:        The exchange's state
399  * @xid:          The exchange ID
400  * @ex_list:      Handle used by the EM to track free exchanges
401  * @ex_lock:      Lock that protects the exchange
402  * @ex_refcnt:    Reference count
403  * @timeout_work: Handle for timeout handler
404  * @lp:           The local port that this exchange is on
405  * @oxid:         Originator's exchange ID
406  * @rxid:         Responder's exchange ID
407  * @oid:          Originator's FCID
408  * @sid:          Source FCID
409  * @did:          Destination FCID
410  * @esb_stat:     ESB exchange status
411  * @r_a_tov:      Resource allocation time out value (in msecs)
412  * @seq_id:       The next sequence ID to use
413  * @encaps:       encapsulation information for lower-level driver
414  * @f_ctl:        F_CTL flags for the sequence
415  * @fh_type:      The frame type
416  * @class:        The class of service
417  * @seq:          The sequence in use on this exchange
418  * @resp_active:  Number of tasks that are concurrently executing @resp().
419  * @resp_task:    If @resp_active > 0, either the task executing @resp(), the
420  *                task that has been interrupted to execute the soft-IRQ
421  *                executing @resp() or NULL if more than one task is executing
422  *                @resp concurrently.
423  * @resp_wq:      Waitqueue for the tasks waiting on @resp_active.
424  * @resp:         Callback for responses on this exchange
425  * @destructor:   Called when destroying the exchange
426  * @arg:          Passed as a void pointer to the resp() callback
427  *
428  * Locking notes: The ex_lock protects following items:
429  *	state, esb_stat, f_ctl, seq.ssb_stat
430  *	seq_id
431  *	sequence allocation
432  */
433 struct fc_exch {
434 	spinlock_t	    ex_lock;
435 	atomic_t	    ex_refcnt;
436 	enum fc_class	    class;
437 	struct fc_exch_mgr  *em;
438 	struct fc_exch_pool *pool;
439 	struct list_head    ex_list;
440 	struct fc_lport	    *lp;
441 	u32		    esb_stat;
442 	u8		    state;
443 	u8		    fh_type;
444 	u8		    seq_id;
445 	u8		    encaps;
446 	u16		    xid;
447 	u16		    oxid;
448 	u16		    rxid;
449 	u32		    oid;
450 	u32		    sid;
451 	u32		    did;
452 	u32		    r_a_tov;
453 	u32		    f_ctl;
454 	struct fc_seq       seq;
455 	int		    resp_active;
456 	struct task_struct  *resp_task;
457 	wait_queue_head_t   resp_wq;
458 	void		    (*resp)(struct fc_seq *, struct fc_frame *, void *);
459 	void		    *arg;
460 	void		    (*destructor)(struct fc_seq *, void *);
461 	struct delayed_work timeout_work;
462 } ____cacheline_aligned_in_smp;
463 #define	fc_seq_exch(sp) container_of(sp, struct fc_exch, seq)
464 
465 
466 struct libfc_function_template {
467 	/*
468 	 * Interface to send a FC frame
469 	 *
470 	 * STATUS: REQUIRED
471 	 */
472 	int (*frame_send)(struct fc_lport *, struct fc_frame *);
473 
474 	/*
475 	 * Interface to send ELS/CT frames
476 	 *
477 	 * STATUS: OPTIONAL
478 	 */
479 	struct fc_seq *(*elsct_send)(struct fc_lport *, u32 did,
480 				     struct fc_frame *, unsigned int op,
481 				     void (*resp)(struct fc_seq *,
482 					     struct fc_frame *, void *arg),
483 				     void *arg, u32 timer_msec);
484 
485 	/*
486 	 * Sets up the DDP context for a given exchange id on the given
487 	 * scatterlist if LLD supports DDP for large receive.
488 	 *
489 	 * STATUS: OPTIONAL
490 	 */
491 	int (*ddp_setup)(struct fc_lport *, u16, struct scatterlist *,
492 			 unsigned int);
493 	/*
494 	 * Completes the DDP transfer and returns the length of data DDPed
495 	 * for the given exchange id.
496 	 *
497 	 * STATUS: OPTIONAL
498 	 */
499 	int (*ddp_done)(struct fc_lport *, u16);
500 	/*
501 	 * Sets up the DDP context for a given exchange id on the given
502 	 * scatterlist if LLD supports DDP for target.
503 	 *
504 	 * STATUS: OPTIONAL
505 	 */
506 	int (*ddp_target)(struct fc_lport *, u16, struct scatterlist *,
507 			  unsigned int);
508 	/*
509 	 * Allow LLD to fill its own Link Error Status Block
510 	 *
511 	 * STATUS: OPTIONAL
512 	 */
513 	void (*get_lesb)(struct fc_lport *, struct fc_els_lesb *lesb);
514 
515 	/*
516 	 * Reset an exchange manager, completing all sequences and exchanges.
517 	 * If s_id is non-zero, reset only exchanges originating from that FID.
518 	 * If d_id is non-zero, reset only exchanges sending to that FID.
519 	 *
520 	 * STATUS: OPTIONAL
521 	 */
522 	void (*exch_mgr_reset)(struct fc_lport *, u32 s_id, u32 d_id);
523 
524 	/*
525 	 * Set the local port FC_ID.
526 	 *
527 	 * This may be provided by the LLD to allow it to be
528 	 * notified when the local port is assigned a FC-ID.
529 	 *
530 	 * The frame, if non-NULL, is the incoming frame with the
531 	 * FLOGI LS_ACC or FLOGI, and may contain the granted MAC
532 	 * address for the LLD.  The frame pointer may be NULL if
533 	 * no MAC is associated with this assignment (LOGO or PLOGI).
534 	 *
535 	 * If FC_ID is non-zero, r_a_tov and e_d_tov must be valid.
536 	 *
537 	 * Note: this is called with the local port mutex held.
538 	 *
539 	 * STATUS: OPTIONAL
540 	 */
541 	void (*lport_set_port_id)(struct fc_lport *, u32 port_id,
542 				  struct fc_frame *);
543 
544 	/*
545 	 * Callback routine after the remote port is logged in
546 	 *
547 	 * STATUS: OPTIONAL
548 	 */
549 	void (*rport_event_callback)(struct fc_lport *,
550 				     struct fc_rport_priv *,
551 				     enum fc_rport_event);
552 
553 	/*
554 	 * Send a fcp cmd from fsp pkt.
555 	 * Called with the SCSI host lock unlocked and irqs disabled.
556 	 *
557 	 * The resp handler is called when FCP_RSP received.
558 	 *
559 	 * STATUS: OPTIONAL
560 	 */
561 	int (*fcp_cmd_send)(struct fc_lport *, struct fc_fcp_pkt *,
562 			    void (*resp)(struct fc_seq *, struct fc_frame *,
563 					 void *));
564 
565 	/*
566 	 * Cleanup the FCP layer, used during link down and reset
567 	 *
568 	 * STATUS: OPTIONAL
569 	 */
570 	void (*fcp_cleanup)(struct fc_lport *);
571 
572 	/*
573 	 * Abort all I/O on a local port
574 	 *
575 	 * STATUS: OPTIONAL
576 	 */
577 	void (*fcp_abort_io)(struct fc_lport *);
578 
579 	/*
580 	 * Receive a request for the discovery layer.
581 	 *
582 	 * STATUS: OPTIONAL
583 	 */
584 	void (*disc_recv_req)(struct fc_lport *, struct fc_frame *);
585 
586 	/*
587 	 * Start discovery for a local port.
588 	 *
589 	 * STATUS: OPTIONAL
590 	 */
591 	void (*disc_start)(void (*disc_callback)(struct fc_lport *,
592 						 enum fc_disc_event),
593 			   struct fc_lport *);
594 
595 	/*
596 	 * Stop discovery for a given lport. This will remove
597 	 * all discovered rports
598 	 *
599 	 * STATUS: OPTIONAL
600 	 */
601 	void (*disc_stop) (struct fc_lport *);
602 
603 	/*
604 	 * Stop discovery for a given lport. This will block
605 	 * until all discovered rports are deleted from the
606 	 * FC transport class
607 	 *
608 	 * STATUS: OPTIONAL
609 	 */
610 	void (*disc_stop_final) (struct fc_lport *);
611 };
612 
613 /**
614  * struct fc_disc - Discovery context
615  * @retry_count:   Number of retries
616  * @pending:       1 if discovery is pending, 0 if not
617  * @requested:     1 if discovery has been requested, 0 if not
618  * @seq_count:     Number of sequences used for discovery
619  * @buf_len:       Length of the discovery buffer
620  * @disc_id:       Discovery ID
621  * @rports:        List of discovered remote ports
622  * @priv:          Private pointer for use by discovery code
623  * @disc_mutex:    Mutex that protects the discovery context
624  * @partial_buf:   Partial name buffer (if names are returned
625  *                 in multiple frames)
626  * @disc_work:     handle for delayed work context
627  * @disc_callback: Callback routine called when discovery completes
628  */
629 struct fc_disc {
630 	unsigned char	      retry_count;
631 	unsigned char	      pending;
632 	unsigned char	      requested;
633 	unsigned short	      seq_count;
634 	unsigned char	      buf_len;
635 	u16		      disc_id;
636 
637 	struct list_head      rports;
638 	void		      *priv;
639 	struct mutex	      disc_mutex;
640 	struct fc_gpn_ft_resp partial_buf;
641 	struct delayed_work   disc_work;
642 
643 	void (*disc_callback)(struct fc_lport *,
644 			      enum fc_disc_event);
645 };
646 
647 /*
648  * Local port notifier and events.
649  */
650 extern struct blocking_notifier_head fc_lport_notifier_head;
651 enum fc_lport_event {
652 	FC_LPORT_EV_ADD,
653 	FC_LPORT_EV_DEL,
654 };
655 
656 /**
657  * struct fc_lport - Local port
658  * @host:                  The SCSI host associated with a local port
659  * @ema_list:              Exchange manager anchor list
660  * @dns_rdata:             The directory server remote port
661  * @ms_rdata:		   The management server remote port
662  * @ptp_rdata:             Point to point remote port
663  * @scsi_priv:             FCP layer internal data
664  * @disc:                  Discovery context
665  * @vports:                Child vports if N_Port
666  * @vport:                 Parent vport if VN_Port
667  * @tt:                    Libfc function template
668  * @link_up:               Link state (1 = link up, 0 = link down)
669  * @qfull:                 Queue state (1 queue is full, 0 queue is not full)
670  * @state:                 Identifies the state
671  * @boot_time:             Timestamp indicating when the local port came online
672  * @host_stats:            SCSI host statistics
673  * @stats:                 FC local port stats (TODO separate libfc LLD stats)
674  * @retry_count:           Number of retries in the current state
675  * @port_id:               FC Port ID
676  * @wwpn:                  World Wide Port Name
677  * @wwnn:                  World Wide Node Name
678  * @service_params:        Common service parameters
679  * @e_d_tov:               Error detection timeout value
680  * @r_a_tov:               Resource allocation timeout value
681  * @rnid_gen:              RNID information
682  * @sg_supp:               Indicates if scatter gather is supported
683  * @seq_offload:           Indicates if sequence offload is supported
684  * @crc_offload:           Indicates if CRC offload is supported
685  * @lro_enabled:           Indicates if large receive offload is supported
686  * @does_npiv:             Supports multiple vports
687  * @npiv_enabled:          Switch/fabric allows NPIV
688  * @mfs:                   The maximum Fibre Channel payload size
689  * @max_retry_count:       The maximum retry attempts
690  * @max_rport_retry_count: The maximum remote port retry attempts
691  * @rport_priv_size:       Size needed by driver after struct fc_rport_priv
692  * @lro_xid:               The maximum XID for LRO
693  * @lso_max:               The maximum large offload send size
694  * @fcts:                  FC-4 type mask
695  * @lp_mutex:              Mutex to protect the local port
696  * @list:                  Linkage on list of vport peers
697  * @retry_work:            Handle to local port for delayed retry context
698  * @prov:		   Pointers available for use by passive FC-4 providers
699  * @lport_list:            Linkage on module-wide list of local ports
700  */
701 struct fc_lport {
702 	/* Associations */
703 	struct Scsi_Host	       *host;
704 	struct list_head	       ema_list;
705 	struct fc_rport_priv	       *dns_rdata;
706 	struct fc_rport_priv	       *ms_rdata;
707 	struct fc_rport_priv	       *ptp_rdata;
708 	void			       *scsi_priv;
709 	struct fc_disc		       disc;
710 
711 	/* Virtual port information */
712 	struct list_head	       vports;
713 	struct fc_vport		       *vport;
714 
715 	/* Operational Information */
716 	struct libfc_function_template tt;
717 	u8			       link_up;
718 	u8			       qfull;
719 	u16			       vlan;
720 	enum fc_lport_state	       state;
721 	unsigned long		       boot_time;
722 	struct fc_host_statistics      host_stats;
723 	struct fc_stats	__percpu       *stats;
724 	u8			       retry_count;
725 
726 	/* Fabric information */
727 	u32			       port_id;
728 	u64			       wwpn;
729 	u64			       wwnn;
730 	unsigned int		       service_params;
731 	unsigned int		       e_d_tov;
732 	unsigned int		       r_a_tov;
733 	struct fc_els_rnid_gen	       rnid_gen;
734 
735 	/* Capabilities */
736 	u32			       sg_supp:1;
737 	u32			       seq_offload:1;
738 	u32			       crc_offload:1;
739 	u32			       lro_enabled:1;
740 	u32			       does_npiv:1;
741 	u32			       npiv_enabled:1;
742 	u32			       point_to_multipoint:1;
743 	u32			       fdmi_enabled:1;
744 	u32			       mfs;
745 	u8			       max_retry_count;
746 	u8			       max_rport_retry_count;
747 	u16			       rport_priv_size;
748 	u16			       link_speed;
749 	u16			       link_supported_speeds;
750 	u16			       lro_xid;
751 	unsigned int		       lso_max;
752 	struct fc_ns_fts	       fcts;
753 
754 	/* Miscellaneous */
755 	struct mutex		       lp_mutex;
756 	struct list_head	       list;
757 	struct delayed_work	       retry_work;
758 	void			       *prov[FC_FC4_PROV_SIZE];
759 	struct list_head	       lport_list;
760 };
761 
762 /**
763  * struct fc4_prov - FC-4 provider registration
764  * @prli:               Handler for incoming PRLI
765  * @prlo:               Handler for session reset
766  * @recv:		Handler for incoming request
767  * @module:		Pointer to module.  May be NULL.
768  */
769 struct fc4_prov {
770 	int (*prli)(struct fc_rport_priv *, u32 spp_len,
771 		    const struct fc_els_spp *spp_in,
772 		    struct fc_els_spp *spp_out);
773 	void (*prlo)(struct fc_rport_priv *);
774 	void (*recv)(struct fc_lport *, struct fc_frame *);
775 	struct module *module;
776 };
777 
778 /*
779  * Register FC-4 provider with libfc.
780  */
781 int fc_fc4_register_provider(enum fc_fh_type type, struct fc4_prov *);
782 void fc_fc4_deregister_provider(enum fc_fh_type type, struct fc4_prov *);
783 
784 /*
785  * FC_LPORT HELPER FUNCTIONS
786  *****************************/
787 
788 /**
789  * fc_lport_test_ready() - Determine if a local port is in the READY state
790  * @lport: The local port to test
791  */
792 static inline int fc_lport_test_ready(struct fc_lport *lport)
793 {
794 	return lport->state == LPORT_ST_READY;
795 }
796 
797 /**
798  * fc_set_wwnn() - Set the World Wide Node Name of a local port
799  * @lport: The local port whose WWNN is to be set
800  * @wwnn:  The new WWNN
801  */
802 static inline void fc_set_wwnn(struct fc_lport *lport, u64 wwnn)
803 {
804 	lport->wwnn = wwnn;
805 }
806 
807 /**
808  * fc_set_wwpn() - Set the World Wide Port Name of a local port
809  * @lport: The local port whose WWPN is to be set
810  * @wwpn:  The new WWPN
811  */
812 static inline void fc_set_wwpn(struct fc_lport *lport, u64 wwpn)
813 {
814 	lport->wwpn = wwpn;
815 }
816 
817 /**
818  * fc_lport_state_enter() - Change a local port's state
819  * @lport: The local port whose state is to change
820  * @state: The new state
821  */
822 static inline void fc_lport_state_enter(struct fc_lport *lport,
823 					enum fc_lport_state state)
824 {
825 	if (state != lport->state)
826 		lport->retry_count = 0;
827 	lport->state = state;
828 }
829 
830 /**
831  * fc_lport_init_stats() - Allocate per-CPU statistics for a local port
832  * @lport: The local port whose statistics are to be initialized
833  */
834 static inline int fc_lport_init_stats(struct fc_lport *lport)
835 {
836 	lport->stats = alloc_percpu(struct fc_stats);
837 	if (!lport->stats)
838 		return -ENOMEM;
839 	return 0;
840 }
841 
842 /**
843  * fc_lport_free_stats() - Free memory for a local port's statistics
844  * @lport: The local port whose statistics are to be freed
845  */
846 static inline void fc_lport_free_stats(struct fc_lport *lport)
847 {
848 	free_percpu(lport->stats);
849 }
850 
851 /**
852  * lport_priv() - Return the private data from a local port
853  * @lport: The local port whose private data is to be retrieved
854  */
855 static inline void *lport_priv(const struct fc_lport *lport)
856 {
857 	return (void *)(lport + 1);
858 }
859 
860 /**
861  * libfc_host_alloc() - Allocate a Scsi_Host with room for a local port and
862  *                      LLD private data
863  * @sht:       The SCSI host template
864  * @priv_size: Size of private data
865  *
866  * Returns: libfc lport
867  */
868 static inline struct fc_lport *
869 libfc_host_alloc(const struct scsi_host_template *sht, int priv_size)
870 {
871 	struct fc_lport *lport;
872 	struct Scsi_Host *shost;
873 
874 	shost = scsi_host_alloc(sht, sizeof(*lport) + priv_size);
875 	if (!shost)
876 		return NULL;
877 	lport = shost_priv(shost);
878 	lport->host = shost;
879 	INIT_LIST_HEAD(&lport->ema_list);
880 	INIT_LIST_HEAD(&lport->vports);
881 	return lport;
882 }
883 
884 /*
885  * FC_FCP HELPER FUNCTIONS
886  *****************************/
887 static inline bool fc_fcp_is_read(const struct fc_fcp_pkt *fsp)
888 {
889 	if (fsp && fsp->cmd)
890 		return fsp->cmd->sc_data_direction == DMA_FROM_DEVICE;
891 	return false;
892 }
893 
894 /*
895  * LOCAL PORT LAYER
896  *****************************/
897 int fc_lport_init(struct fc_lport *);
898 int fc_lport_destroy(struct fc_lport *);
899 int fc_fabric_logoff(struct fc_lport *);
900 int fc_fabric_login(struct fc_lport *);
901 void __fc_linkup(struct fc_lport *);
902 void fc_linkup(struct fc_lport *);
903 void __fc_linkdown(struct fc_lport *);
904 void fc_linkdown(struct fc_lport *);
905 void fc_vport_setlink(struct fc_lport *);
906 void fc_vports_linkchange(struct fc_lport *);
907 int fc_lport_config(struct fc_lport *);
908 int fc_lport_reset(struct fc_lport *);
909 void fc_lport_recv(struct fc_lport *lport, struct fc_frame *fp);
910 int fc_set_mfs(struct fc_lport *, u32 mfs);
911 struct fc_lport *libfc_vport_create(struct fc_vport *, int privsize);
912 struct fc_lport *fc_vport_id_lookup(struct fc_lport *, u32 port_id);
913 int fc_lport_bsg_request(struct bsg_job *);
914 void fc_lport_set_local_id(struct fc_lport *, u32 port_id);
915 void fc_lport_iterate(void (*func)(struct fc_lport *, void *), void *);
916 
917 /*
918  * REMOTE PORT LAYER
919  *****************************/
920 void fc_rport_terminate_io(struct fc_rport *);
921 struct fc_rport_priv *fc_rport_lookup(const struct fc_lport *lport,
922 				      u32 port_id);
923 struct fc_rport_priv *fc_rport_create(struct fc_lport *, u32);
924 void fc_rport_destroy(struct kref *kref);
925 int fc_rport_login(struct fc_rport_priv *rdata);
926 int fc_rport_logoff(struct fc_rport_priv *rdata);
927 void fc_rport_recv_req(struct fc_lport *lport, struct fc_frame *fp);
928 void fc_rport_flush_queue(void);
929 
930 /*
931  * DISCOVERY LAYER
932  *****************************/
933 void fc_disc_init(struct fc_lport *);
934 void fc_disc_config(struct fc_lport *, void *);
935 
936 static inline struct fc_lport *fc_disc_lport(struct fc_disc *disc)
937 {
938 	return container_of(disc, struct fc_lport, disc);
939 }
940 
941 /*
942  * FCP LAYER
943  *****************************/
944 int fc_fcp_init(struct fc_lport *);
945 void fc_fcp_destroy(struct fc_lport *);
946 
947 /*
948  * SCSI INTERACTION LAYER
949  *****************************/
950 int fc_queuecommand(struct Scsi_Host *, struct scsi_cmnd *);
951 int fc_eh_abort(struct scsi_cmnd *);
952 int fc_eh_device_reset(struct scsi_cmnd *);
953 int fc_eh_host_reset(struct scsi_cmnd *);
954 int fc_slave_alloc(struct scsi_device *);
955 
956 /*
957  * ELS/CT interface
958  *****************************/
959 int fc_elsct_init(struct fc_lport *);
960 struct fc_seq *fc_elsct_send(struct fc_lport *, u32 did,
961 				    struct fc_frame *,
962 				    unsigned int op,
963 				    void (*resp)(struct fc_seq *,
964 						 struct fc_frame *,
965 						 void *arg),
966 				    void *arg, u32 timer_msec);
967 void fc_lport_flogi_resp(struct fc_seq *, struct fc_frame *, void *);
968 void fc_lport_logo_resp(struct fc_seq *, struct fc_frame *, void *);
969 void fc_fill_reply_hdr(struct fc_frame *, const struct fc_frame *,
970 		       enum fc_rctl, u32 parm_offset);
971 void fc_fill_hdr(struct fc_frame *, const struct fc_frame *,
972 		 enum fc_rctl, u32 f_ctl, u16 seq_cnt, u32 parm_offset);
973 
974 
975 /*
976  * EXCHANGE MANAGER LAYER
977  *****************************/
978 int fc_exch_init(struct fc_lport *);
979 void fc_exch_update_stats(struct fc_lport *lport);
980 struct fc_seq *fc_exch_seq_send(struct fc_lport *lport,
981 				struct fc_frame *fp,
982 				void (*resp)(struct fc_seq *,
983 					     struct fc_frame *fp,
984 					     void *arg),
985 				void (*destructor)(struct fc_seq *, void *),
986 				void *arg, u32 timer_msec);
987 void fc_seq_els_rsp_send(struct fc_frame *, enum fc_els_cmd,
988 			 struct fc_seq_els_data *);
989 struct fc_seq *fc_seq_start_next(struct fc_seq *sp);
990 void fc_seq_set_resp(struct fc_seq *sp,
991 		     void (*resp)(struct fc_seq *, struct fc_frame *, void *),
992 		     void *arg);
993 struct fc_seq *fc_seq_assign(struct fc_lport *lport, struct fc_frame *fp);
994 void fc_seq_release(struct fc_seq *sp);
995 struct fc_exch_mgr_anchor *fc_exch_mgr_add(struct fc_lport *,
996 					   struct fc_exch_mgr *,
997 					   bool (*match)(struct fc_frame *));
998 void fc_exch_mgr_del(struct fc_exch_mgr_anchor *);
999 int fc_exch_mgr_list_clone(struct fc_lport *src, struct fc_lport *dst);
1000 struct fc_exch_mgr *fc_exch_mgr_alloc(struct fc_lport *, enum fc_class class,
1001 				      u16 min_xid, u16 max_xid,
1002 				      bool (*match)(struct fc_frame *));
1003 void fc_exch_mgr_free(struct fc_lport *);
1004 void fc_exch_recv(struct fc_lport *, struct fc_frame *);
1005 void fc_exch_mgr_reset(struct fc_lport *, u32 s_id, u32 d_id);
1006 int fc_seq_send(struct fc_lport *lport, struct fc_seq *sp, struct fc_frame *fp);
1007 int fc_seq_exch_abort(const struct fc_seq *, unsigned int timer_msec);
1008 void fc_exch_done(struct fc_seq *sp);
1009 
1010 /*
1011  * Functions for fc_functions_template
1012  */
1013 void fc_get_host_speed(struct Scsi_Host *);
1014 void fc_get_host_port_state(struct Scsi_Host *);
1015 void fc_set_rport_loss_tmo(struct fc_rport *, u32 timeout);
1016 struct fc_host_statistics *fc_get_host_stats(struct Scsi_Host *);
1017 
1018 #endif /* _LIBFC_H_ */
1019