xref: /openbmc/linux/include/scsi/libfc.h (revision 76426e23)
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  * Structure and function definitions for managing Fibre Channel Exchanges
356  * and Sequences
357  *
358  * fc_exch holds state for one exchange and links to its active sequence.
359  *
360  * fc_seq holds the state for an individual sequence.
361  */
362 
363 struct fc_exch_mgr;
364 struct fc_exch_mgr_anchor;
365 extern u16 fc_cpu_mask;	/* cpu mask for possible cpus */
366 
367 /**
368  * struct fc_seq - FC sequence
369  * @id:       The sequence ID
370  * @ssb_stat: Status flags for the sequence status block (SSB)
371  * @cnt:      Number of frames sent so far
372  * @rec_data: FC-4 value for REC
373  */
374 struct fc_seq {
375 	u8  id;
376 	u16 ssb_stat;
377 	u16 cnt;
378 	u32 rec_data;
379 };
380 
381 #define FC_EX_DONE		(1 << 0) /* ep is completed */
382 #define FC_EX_RST_CLEANUP	(1 << 1) /* reset is forcing completion */
383 #define FC_EX_QUARANTINE	(1 << 2) /* exch is quarantined */
384 
385 /**
386  * struct fc_exch - Fibre Channel Exchange
387  * @em:           Exchange manager
388  * @pool:         Exchange pool
389  * @state:        The exchange's state
390  * @xid:          The exchange ID
391  * @ex_list:      Handle used by the EM to track free exchanges
392  * @ex_lock:      Lock that protects the exchange
393  * @ex_refcnt:    Reference count
394  * @timeout_work: Handle for timeout handler
395  * @lp:           The local port that this exchange is on
396  * @oxid:         Originator's exchange ID
397  * @rxid:         Responder's exchange ID
398  * @oid:          Originator's FCID
399  * @sid:          Source FCID
400  * @did:          Destination FCID
401  * @esb_stat:     ESB exchange status
402  * @r_a_tov:      Resouce allocation time out value (in msecs)
403  * @seq_id:       The next sequence ID to use
404  * @encaps:       encapsulation information for lower-level driver
405  * @f_ctl:        F_CTL flags for the sequence
406  * @fh_type:      The frame type
407  * @class:        The class of service
408  * @seq:          The sequence in use on this exchange
409  * @resp_active:  Number of tasks that are concurrently executing @resp().
410  * @resp_task:    If @resp_active > 0, either the task executing @resp(), the
411  *                task that has been interrupted to execute the soft-IRQ
412  *                executing @resp() or NULL if more than one task is executing
413  *                @resp concurrently.
414  * @resp_wq:      Waitqueue for the tasks waiting on @resp_active.
415  * @resp:         Callback for responses on this exchange
416  * @destructor:   Called when destroying the exchange
417  * @arg:          Passed as a void pointer to the resp() callback
418  *
419  * Locking notes: The ex_lock protects following items:
420  *	state, esb_stat, f_ctl, seq.ssb_stat
421  *	seq_id
422  *	sequence allocation
423  */
424 struct fc_exch {
425 	spinlock_t	    ex_lock;
426 	atomic_t	    ex_refcnt;
427 	enum fc_class	    class;
428 	struct fc_exch_mgr  *em;
429 	struct fc_exch_pool *pool;
430 	struct list_head    ex_list;
431 	struct fc_lport	    *lp;
432 	u32		    esb_stat;
433 	u8		    state;
434 	u8		    fh_type;
435 	u8		    seq_id;
436 	u8		    encaps;
437 	u16		    xid;
438 	u16		    oxid;
439 	u16		    rxid;
440 	u32		    oid;
441 	u32		    sid;
442 	u32		    did;
443 	u32		    r_a_tov;
444 	u32		    f_ctl;
445 	struct fc_seq       seq;
446 	int		    resp_active;
447 	struct task_struct  *resp_task;
448 	wait_queue_head_t   resp_wq;
449 	void		    (*resp)(struct fc_seq *, struct fc_frame *, void *);
450 	void		    *arg;
451 	void		    (*destructor)(struct fc_seq *, void *);
452 	struct delayed_work timeout_work;
453 } ____cacheline_aligned_in_smp;
454 #define	fc_seq_exch(sp) container_of(sp, struct fc_exch, seq)
455 
456 
457 struct libfc_function_template {
458 	/*
459 	 * Interface to send a FC frame
460 	 *
461 	 * STATUS: REQUIRED
462 	 */
463 	int (*frame_send)(struct fc_lport *, struct fc_frame *);
464 
465 	/*
466 	 * Interface to send ELS/CT frames
467 	 *
468 	 * STATUS: OPTIONAL
469 	 */
470 	struct fc_seq *(*elsct_send)(struct fc_lport *, u32 did,
471 				     struct fc_frame *, unsigned int op,
472 				     void (*resp)(struct fc_seq *,
473 					     struct fc_frame *, void *arg),
474 				     void *arg, u32 timer_msec);
475 
476 	/*
477 	 * Sets up the DDP context for a given exchange id on the given
478 	 * scatterlist if LLD supports DDP for large receive.
479 	 *
480 	 * STATUS: OPTIONAL
481 	 */
482 	int (*ddp_setup)(struct fc_lport *, u16, struct scatterlist *,
483 			 unsigned int);
484 	/*
485 	 * Completes the DDP transfer and returns the length of data DDPed
486 	 * for the given exchange id.
487 	 *
488 	 * STATUS: OPTIONAL
489 	 */
490 	int (*ddp_done)(struct fc_lport *, u16);
491 	/*
492 	 * Sets up the DDP context for a given exchange id on the given
493 	 * scatterlist if LLD supports DDP for target.
494 	 *
495 	 * STATUS: OPTIONAL
496 	 */
497 	int (*ddp_target)(struct fc_lport *, u16, struct scatterlist *,
498 			  unsigned int);
499 	/*
500 	 * Allow LLD to fill its own Link Error Status Block
501 	 *
502 	 * STATUS: OPTIONAL
503 	 */
504 	void (*get_lesb)(struct fc_lport *, struct fc_els_lesb *lesb);
505 
506 	/*
507 	 * Reset an exchange manager, completing all sequences and exchanges.
508 	 * If s_id is non-zero, reset only exchanges originating from that FID.
509 	 * If d_id is non-zero, reset only exchanges sending to that FID.
510 	 *
511 	 * STATUS: OPTIONAL
512 	 */
513 	void (*exch_mgr_reset)(struct fc_lport *, u32 s_id, u32 d_id);
514 
515 	/*
516 	 * Set the local port FC_ID.
517 	 *
518 	 * This may be provided by the LLD to allow it to be
519 	 * notified when the local port is assigned a FC-ID.
520 	 *
521 	 * The frame, if non-NULL, is the incoming frame with the
522 	 * FLOGI LS_ACC or FLOGI, and may contain the granted MAC
523 	 * address for the LLD.  The frame pointer may be NULL if
524 	 * no MAC is associated with this assignment (LOGO or PLOGI).
525 	 *
526 	 * If FC_ID is non-zero, r_a_tov and e_d_tov must be valid.
527 	 *
528 	 * Note: this is called with the local port mutex held.
529 	 *
530 	 * STATUS: OPTIONAL
531 	 */
532 	void (*lport_set_port_id)(struct fc_lport *, u32 port_id,
533 				  struct fc_frame *);
534 
535 	/*
536 	 * Callback routine after the remote port is logged in
537 	 *
538 	 * STATUS: OPTIONAL
539 	 */
540 	void (*rport_event_callback)(struct fc_lport *,
541 				     struct fc_rport_priv *,
542 				     enum fc_rport_event);
543 
544 	/*
545 	 * Send a fcp cmd from fsp pkt.
546 	 * Called with the SCSI host lock unlocked and irqs disabled.
547 	 *
548 	 * The resp handler is called when FCP_RSP received.
549 	 *
550 	 * STATUS: OPTIONAL
551 	 */
552 	int (*fcp_cmd_send)(struct fc_lport *, struct fc_fcp_pkt *,
553 			    void (*resp)(struct fc_seq *, struct fc_frame *,
554 					 void *));
555 
556 	/*
557 	 * Cleanup the FCP layer, used during link down and reset
558 	 *
559 	 * STATUS: OPTIONAL
560 	 */
561 	void (*fcp_cleanup)(struct fc_lport *);
562 
563 	/*
564 	 * Abort all I/O on a local port
565 	 *
566 	 * STATUS: OPTIONAL
567 	 */
568 	void (*fcp_abort_io)(struct fc_lport *);
569 
570 	/*
571 	 * Receive a request for the discovery layer.
572 	 *
573 	 * STATUS: OPTIONAL
574 	 */
575 	void (*disc_recv_req)(struct fc_lport *, struct fc_frame *);
576 
577 	/*
578 	 * Start discovery for a local port.
579 	 *
580 	 * STATUS: OPTIONAL
581 	 */
582 	void (*disc_start)(void (*disc_callback)(struct fc_lport *,
583 						 enum fc_disc_event),
584 			   struct fc_lport *);
585 
586 	/*
587 	 * Stop discovery for a given lport. This will remove
588 	 * all discovered rports
589 	 *
590 	 * STATUS: OPTIONAL
591 	 */
592 	void (*disc_stop) (struct fc_lport *);
593 
594 	/*
595 	 * Stop discovery for a given lport. This will block
596 	 * until all discovered rports are deleted from the
597 	 * FC transport class
598 	 *
599 	 * STATUS: OPTIONAL
600 	 */
601 	void (*disc_stop_final) (struct fc_lport *);
602 };
603 
604 /**
605  * struct fc_disc - Discovery context
606  * @retry_count:   Number of retries
607  * @pending:       1 if discovery is pending, 0 if not
608  * @requested:     1 if discovery has been requested, 0 if not
609  * @seq_count:     Number of sequences used for discovery
610  * @buf_len:       Length of the discovery buffer
611  * @disc_id:       Discovery ID
612  * @rports:        List of discovered remote ports
613  * @priv:          Private pointer for use by discovery code
614  * @disc_mutex:    Mutex that protects the discovery context
615  * @partial_buf:   Partial name buffer (if names are returned
616  *                 in multiple frames)
617  * @disc_work:     handle for delayed work context
618  * @disc_callback: Callback routine called when discovery completes
619  */
620 struct fc_disc {
621 	unsigned char	      retry_count;
622 	unsigned char	      pending;
623 	unsigned char	      requested;
624 	unsigned short	      seq_count;
625 	unsigned char	      buf_len;
626 	u16		      disc_id;
627 
628 	struct list_head      rports;
629 	void		      *priv;
630 	struct mutex	      disc_mutex;
631 	struct fc_gpn_ft_resp partial_buf;
632 	struct delayed_work   disc_work;
633 
634 	void (*disc_callback)(struct fc_lport *,
635 			      enum fc_disc_event);
636 };
637 
638 /*
639  * Local port notifier and events.
640  */
641 extern struct blocking_notifier_head fc_lport_notifier_head;
642 enum fc_lport_event {
643 	FC_LPORT_EV_ADD,
644 	FC_LPORT_EV_DEL,
645 };
646 
647 /**
648  * struct fc_lport - Local port
649  * @host:                  The SCSI host associated with a local port
650  * @ema_list:              Exchange manager anchor list
651  * @dns_rdata:             The directory server remote port
652  * @ms_rdata:		   The management server remote port
653  * @ptp_rdata:             Point to point remote port
654  * @scsi_priv:             FCP layer internal data
655  * @disc:                  Discovery context
656  * @vports:                Child vports if N_Port
657  * @vport:                 Parent vport if VN_Port
658  * @tt:                    Libfc function template
659  * @link_up:               Link state (1 = link up, 0 = link down)
660  * @qfull:                 Queue state (1 queue is full, 0 queue is not full)
661  * @state:                 Identifies the state
662  * @boot_time:             Timestamp indicating when the local port came online
663  * @host_stats:            SCSI host statistics
664  * @stats:                 FC local port stats (TODO separate libfc LLD stats)
665  * @retry_count:           Number of retries in the current state
666  * @port_id:               FC Port ID
667  * @wwpn:                  World Wide Port Name
668  * @wwnn:                  World Wide Node Name
669  * @service_params:        Common service parameters
670  * @e_d_tov:               Error detection timeout value
671  * @r_a_tov:               Resouce allocation timeout value
672  * @rnid_gen:              RNID information
673  * @sg_supp:               Indicates if scatter gather is supported
674  * @seq_offload:           Indicates if sequence offload is supported
675  * @crc_offload:           Indicates if CRC offload is supported
676  * @lro_enabled:           Indicates if large receive offload is supported
677  * @does_npiv:             Supports multiple vports
678  * @npiv_enabled:          Switch/fabric allows NPIV
679  * @mfs:                   The maximum Fibre Channel payload size
680  * @max_retry_count:       The maximum retry attempts
681  * @max_rport_retry_count: The maximum remote port retry attempts
682  * @rport_priv_size:       Size needed by driver after struct fc_rport_priv
683  * @lro_xid:               The maximum XID for LRO
684  * @lso_max:               The maximum large offload send size
685  * @fcts:                  FC-4 type mask
686  * @lp_mutex:              Mutex to protect the local port
687  * @list:                  Linkage on list of vport peers
688  * @retry_work:            Handle to local port for delayed retry context
689  * @prov:		   Pointers available for use by passive FC-4 providers
690  * @lport_list:            Linkage on module-wide list of local ports
691  */
692 struct fc_lport {
693 	/* Associations */
694 	struct Scsi_Host	       *host;
695 	struct list_head	       ema_list;
696 	struct fc_rport_priv	       *dns_rdata;
697 	struct fc_rport_priv	       *ms_rdata;
698 	struct fc_rport_priv	       *ptp_rdata;
699 	void			       *scsi_priv;
700 	struct fc_disc		       disc;
701 
702 	/* Virtual port information */
703 	struct list_head	       vports;
704 	struct fc_vport		       *vport;
705 
706 	/* Operational Information */
707 	struct libfc_function_template tt;
708 	u8			       link_up;
709 	u8			       qfull;
710 	u16			       vlan;
711 	enum fc_lport_state	       state;
712 	unsigned long		       boot_time;
713 	struct fc_host_statistics      host_stats;
714 	struct fc_stats	__percpu       *stats;
715 	u8			       retry_count;
716 
717 	/* Fabric information */
718 	u32			       port_id;
719 	u64			       wwpn;
720 	u64			       wwnn;
721 	unsigned int		       service_params;
722 	unsigned int		       e_d_tov;
723 	unsigned int		       r_a_tov;
724 	struct fc_els_rnid_gen	       rnid_gen;
725 
726 	/* Capabilities */
727 	u32			       sg_supp:1;
728 	u32			       seq_offload:1;
729 	u32			       crc_offload:1;
730 	u32			       lro_enabled:1;
731 	u32			       does_npiv:1;
732 	u32			       npiv_enabled:1;
733 	u32			       point_to_multipoint:1;
734 	u32			       fdmi_enabled:1;
735 	u32			       mfs;
736 	u8			       max_retry_count;
737 	u8			       max_rport_retry_count;
738 	u16			       rport_priv_size;
739 	u16			       link_speed;
740 	u16			       link_supported_speeds;
741 	u16			       lro_xid;
742 	unsigned int		       lso_max;
743 	struct fc_ns_fts	       fcts;
744 
745 	/* Miscellaneous */
746 	struct mutex		       lp_mutex;
747 	struct list_head	       list;
748 	struct delayed_work	       retry_work;
749 	void			       *prov[FC_FC4_PROV_SIZE];
750 	struct list_head	       lport_list;
751 };
752 
753 /**
754  * struct fc4_prov - FC-4 provider registration
755  * @prli:               Handler for incoming PRLI
756  * @prlo:               Handler for session reset
757  * @recv:		Handler for incoming request
758  * @module:		Pointer to module.  May be NULL.
759  */
760 struct fc4_prov {
761 	int (*prli)(struct fc_rport_priv *, u32 spp_len,
762 		    const struct fc_els_spp *spp_in,
763 		    struct fc_els_spp *spp_out);
764 	void (*prlo)(struct fc_rport_priv *);
765 	void (*recv)(struct fc_lport *, struct fc_frame *);
766 	struct module *module;
767 };
768 
769 /*
770  * Register FC-4 provider with libfc.
771  */
772 int fc_fc4_register_provider(enum fc_fh_type type, struct fc4_prov *);
773 void fc_fc4_deregister_provider(enum fc_fh_type type, struct fc4_prov *);
774 
775 /*
776  * FC_LPORT HELPER FUNCTIONS
777  *****************************/
778 
779 /**
780  * fc_lport_test_ready() - Determine if a local port is in the READY state
781  * @lport: The local port to test
782  */
783 static inline int fc_lport_test_ready(struct fc_lport *lport)
784 {
785 	return lport->state == LPORT_ST_READY;
786 }
787 
788 /**
789  * fc_set_wwnn() - Set the World Wide Node Name of a local port
790  * @lport: The local port whose WWNN is to be set
791  * @wwnn:  The new WWNN
792  */
793 static inline void fc_set_wwnn(struct fc_lport *lport, u64 wwnn)
794 {
795 	lport->wwnn = wwnn;
796 }
797 
798 /**
799  * fc_set_wwpn() - Set the World Wide Port Name of a local port
800  * @lport: The local port whose WWPN is to be set
801  * @wwpn:  The new WWPN
802  */
803 static inline void fc_set_wwpn(struct fc_lport *lport, u64 wwpn)
804 {
805 	lport->wwpn = wwpn;
806 }
807 
808 /**
809  * fc_lport_state_enter() - Change a local port's state
810  * @lport: The local port whose state is to change
811  * @state: The new state
812  */
813 static inline void fc_lport_state_enter(struct fc_lport *lport,
814 					enum fc_lport_state state)
815 {
816 	if (state != lport->state)
817 		lport->retry_count = 0;
818 	lport->state = state;
819 }
820 
821 /**
822  * fc_lport_init_stats() - Allocate per-CPU statistics for a local port
823  * @lport: The local port whose statistics are to be initialized
824  */
825 static inline int fc_lport_init_stats(struct fc_lport *lport)
826 {
827 	lport->stats = alloc_percpu(struct fc_stats);
828 	if (!lport->stats)
829 		return -ENOMEM;
830 	return 0;
831 }
832 
833 /**
834  * fc_lport_free_stats() - Free memory for a local port's statistics
835  * @lport: The local port whose statistics are to be freed
836  */
837 static inline void fc_lport_free_stats(struct fc_lport *lport)
838 {
839 	free_percpu(lport->stats);
840 }
841 
842 /**
843  * lport_priv() - Return the private data from a local port
844  * @lport: The local port whose private data is to be retreived
845  */
846 static inline void *lport_priv(const struct fc_lport *lport)
847 {
848 	return (void *)(lport + 1);
849 }
850 
851 /**
852  * libfc_host_alloc() - Allocate a Scsi_Host with room for a local port and
853  *                      LLD private data
854  * @sht:       The SCSI host template
855  * @priv_size: Size of private data
856  *
857  * Returns: libfc lport
858  */
859 static inline struct fc_lport *
860 libfc_host_alloc(struct scsi_host_template *sht, int priv_size)
861 {
862 	struct fc_lport *lport;
863 	struct Scsi_Host *shost;
864 
865 	shost = scsi_host_alloc(sht, sizeof(*lport) + priv_size);
866 	if (!shost)
867 		return NULL;
868 	lport = shost_priv(shost);
869 	lport->host = shost;
870 	INIT_LIST_HEAD(&lport->ema_list);
871 	INIT_LIST_HEAD(&lport->vports);
872 	return lport;
873 }
874 
875 /*
876  * FC_FCP HELPER FUNCTIONS
877  *****************************/
878 static inline bool fc_fcp_is_read(const struct fc_fcp_pkt *fsp)
879 {
880 	if (fsp && fsp->cmd)
881 		return fsp->cmd->sc_data_direction == DMA_FROM_DEVICE;
882 	return false;
883 }
884 
885 /*
886  * LOCAL PORT LAYER
887  *****************************/
888 int fc_lport_init(struct fc_lport *);
889 int fc_lport_destroy(struct fc_lport *);
890 int fc_fabric_logoff(struct fc_lport *);
891 int fc_fabric_login(struct fc_lport *);
892 void __fc_linkup(struct fc_lport *);
893 void fc_linkup(struct fc_lport *);
894 void __fc_linkdown(struct fc_lport *);
895 void fc_linkdown(struct fc_lport *);
896 void fc_vport_setlink(struct fc_lport *);
897 void fc_vports_linkchange(struct fc_lport *);
898 int fc_lport_config(struct fc_lport *);
899 int fc_lport_reset(struct fc_lport *);
900 void fc_lport_recv(struct fc_lport *lport, struct fc_frame *fp);
901 int fc_set_mfs(struct fc_lport *, u32 mfs);
902 struct fc_lport *libfc_vport_create(struct fc_vport *, int privsize);
903 struct fc_lport *fc_vport_id_lookup(struct fc_lport *, u32 port_id);
904 int fc_lport_bsg_request(struct bsg_job *);
905 void fc_lport_set_local_id(struct fc_lport *, u32 port_id);
906 void fc_lport_iterate(void (*func)(struct fc_lport *, void *), void *);
907 
908 /*
909  * REMOTE PORT LAYER
910  *****************************/
911 void fc_rport_terminate_io(struct fc_rport *);
912 struct fc_rport_priv *fc_rport_lookup(const struct fc_lport *lport,
913 				      u32 port_id);
914 struct fc_rport_priv *fc_rport_create(struct fc_lport *, u32);
915 void fc_rport_destroy(struct kref *kref);
916 int fc_rport_login(struct fc_rport_priv *rdata);
917 int fc_rport_logoff(struct fc_rport_priv *rdata);
918 void fc_rport_recv_req(struct fc_lport *lport, struct fc_frame *fp);
919 void fc_rport_flush_queue(void);
920 
921 /*
922  * DISCOVERY LAYER
923  *****************************/
924 void fc_disc_init(struct fc_lport *);
925 void fc_disc_config(struct fc_lport *, void *);
926 
927 static inline struct fc_lport *fc_disc_lport(struct fc_disc *disc)
928 {
929 	return container_of(disc, struct fc_lport, disc);
930 }
931 
932 /*
933  * FCP LAYER
934  *****************************/
935 int fc_fcp_init(struct fc_lport *);
936 void fc_fcp_destroy(struct fc_lport *);
937 
938 /*
939  * SCSI INTERACTION LAYER
940  *****************************/
941 int fc_queuecommand(struct Scsi_Host *, struct scsi_cmnd *);
942 int fc_eh_abort(struct scsi_cmnd *);
943 int fc_eh_device_reset(struct scsi_cmnd *);
944 int fc_eh_host_reset(struct scsi_cmnd *);
945 int fc_slave_alloc(struct scsi_device *);
946 
947 /*
948  * ELS/CT interface
949  *****************************/
950 int fc_elsct_init(struct fc_lport *);
951 struct fc_seq *fc_elsct_send(struct fc_lport *, u32 did,
952 				    struct fc_frame *,
953 				    unsigned int op,
954 				    void (*resp)(struct fc_seq *,
955 						 struct fc_frame *,
956 						 void *arg),
957 				    void *arg, u32 timer_msec);
958 void fc_lport_flogi_resp(struct fc_seq *, struct fc_frame *, void *);
959 void fc_lport_logo_resp(struct fc_seq *, struct fc_frame *, void *);
960 void fc_fill_reply_hdr(struct fc_frame *, const struct fc_frame *,
961 		       enum fc_rctl, u32 parm_offset);
962 void fc_fill_hdr(struct fc_frame *, const struct fc_frame *,
963 		 enum fc_rctl, u32 f_ctl, u16 seq_cnt, u32 parm_offset);
964 
965 
966 /*
967  * EXCHANGE MANAGER LAYER
968  *****************************/
969 int fc_exch_init(struct fc_lport *);
970 void fc_exch_update_stats(struct fc_lport *lport);
971 struct fc_seq *fc_exch_seq_send(struct fc_lport *lport,
972 				struct fc_frame *fp,
973 				void (*resp)(struct fc_seq *,
974 					     struct fc_frame *fp,
975 					     void *arg),
976 				void (*destructor)(struct fc_seq *, void *),
977 				void *arg, u32 timer_msec);
978 void fc_seq_els_rsp_send(struct fc_frame *, enum fc_els_cmd,
979 			 struct fc_seq_els_data *);
980 struct fc_seq *fc_seq_start_next(struct fc_seq *sp);
981 void fc_seq_set_resp(struct fc_seq *sp,
982 		     void (*resp)(struct fc_seq *, struct fc_frame *, void *),
983 		     void *arg);
984 struct fc_seq *fc_seq_assign(struct fc_lport *lport, struct fc_frame *fp);
985 void fc_seq_release(struct fc_seq *sp);
986 struct fc_exch_mgr_anchor *fc_exch_mgr_add(struct fc_lport *,
987 					   struct fc_exch_mgr *,
988 					   bool (*match)(struct fc_frame *));
989 void fc_exch_mgr_del(struct fc_exch_mgr_anchor *);
990 int fc_exch_mgr_list_clone(struct fc_lport *src, struct fc_lport *dst);
991 struct fc_exch_mgr *fc_exch_mgr_alloc(struct fc_lport *, enum fc_class class,
992 				      u16 min_xid, u16 max_xid,
993 				      bool (*match)(struct fc_frame *));
994 void fc_exch_mgr_free(struct fc_lport *);
995 void fc_exch_recv(struct fc_lport *, struct fc_frame *);
996 void fc_exch_mgr_reset(struct fc_lport *, u32 s_id, u32 d_id);
997 int fc_seq_send(struct fc_lport *lport, struct fc_seq *sp, struct fc_frame *fp);
998 int fc_seq_exch_abort(const struct fc_seq *, unsigned int timer_msec);
999 void fc_exch_done(struct fc_seq *sp);
1000 
1001 /*
1002  * Functions for fc_functions_template
1003  */
1004 void fc_get_host_speed(struct Scsi_Host *);
1005 void fc_get_host_port_state(struct Scsi_Host *);
1006 void fc_set_rport_loss_tmo(struct fc_rport *, u32 timeout);
1007 struct fc_host_statistics *fc_get_host_stats(struct Scsi_Host *);
1008 
1009 #endif /* _LIBFC_H_ */
1010