11  * Fibre Channel exchange and sequence handling.
40  * fc_exch holds state for one exchange and links to its active sequence.
42  * fc_seq holds the state for an individual sequence.
132  * to have one per CPU. The sequence manager is one per exchange manager
136  * assigned by the Sequence Initiator that shall be unique for a specific
137  * D_ID and S_ID pair while the Sequence is open."   Note that it isn't
142  * The exchange and its sequence are freed when the last sequence is received.
154  * Sequence event handling:
162  *	    The sequence is marked complete.
165  *	    with exchange and sequence tuple.
167  *	    When we receive the next sequence on the same exchange, we can
168  *	    retire the previous sequence ID.  (XXX not implemented).
170  *	    R_A_TOV frees the sequence ID.  If we're waiting for ACK,
181  *	    Allocate sequence for first frame received.
186  *	    Deallocate sequence
190  * For now, we neglect conditions where only part of a sequence was
200  * sequence allocation and deallocation must be locked.
202  *  - sequence allocation must be locked by exch lock.
486 	 * update sequence count if this frame is carrying  in fc_seq_send_locked()
487 	 * multiple FC frames when sequence offload is enabled  in fc_seq_send_locked()
505 	 * Update the exchange and sequence flags,  in fc_seq_send_locked()
506 	 * assuming all frames for the sequence have been sent.  in fc_seq_send_locked()
507 	 * We can only be called to send once for each sequence.  in fc_seq_send_locked()
517  * fc_seq_send() - Send a frame using existing sequence/exchange pair
519  * @sp:	   The sequence to be sent
538  * fc_seq_alloc() - Allocate a sequence for a given exchange
539  * @ep:	    The exchange to allocate a new sequence for
540  * @seq_id: The sequence ID to be used
543  * By implication, any previously originated sequence on this exchange
544  * is complete, and we reallocate the same sequence.
558  * fc_seq_start_next_locked() - Allocate a new sequence on the same
559  *				exchange as the supplied sequence
560  * @sp: The sequence/exchange to get a new sequence for
573  * fc_seq_start_next() - Lock the exchange and get a new sequence
574  *			 for a given sequence/exchange pair
575  * @sp: The sequence/exchange to get a new exchange for
590  * Set the response handler for the exchange associated with a sequence.
622  * Abort an exchange and sequence. Generally called because of a
649 	 * Send the abort on a new sequence if possible.  in fc_exch_abort_locked()
660 		 * Send an abort for the sequence that timed out.  in fc_exch_abort_locked()
675 		 * sequence active until next timeout.  in fc_exch_abort_locked()
684  * fc_seq_exch_abort() - Abort an exchange and sequence
685  * @req_sp:	The sequence to be aborted
708  * @sp:	   The sequence pointer to pass through to ->resp()
961  * fc_exch_done() - Indicate that an exchange/sequence tuple is complete and
963  * @sp: The sequence that has completed
1029  * fc_seq_lookup_recip() - Find a sequence where the other end
1030  *			   originated the sequence
1033  * @fp:	   The frame associated with the sequence we're looking for
1053 	 * Lookup or create the exchange if we will be creating the sequence.  in fc_seq_lookup_recip()
1084 		 * new sequence - find the exchange  in fc_seq_lookup_recip()
1109 	 * Find or create the sequence.  in fc_seq_lookup_recip()
1122 				 * frame of sequence exchange. This is needed  in fc_seq_lookup_recip()
1139 				/* sequence/exch should exist */  in fc_seq_lookup_recip()
1161  * fc_seq_lookup_orig() - Find a sequence where this end
1162  *			  originated the sequence
1164  * @fp:	   The frame associated with the sequence we're looking for
1166  * Does not hold the sequence for the caller.
1203  * Note this must be done before the first sequence of the exchange is sent.
1220  *			   the existing sequence/exchange.
1250  * fc_seq_send_last() - Send a sequence that is the last in the exchange
1251  * @sp:	     The sequence that is to be sent
1252  * @fp:	     The frame that will be sent on the sequence
1270  * @sp:	   The sequence to send the ACK on
1302 		 * Last ACK uses bits 7-6 (continue sequence),  in fc_seq_send_ack()
1381 	 * Last ACK uses bits 7-6 (continue sequence),  in fc_exch_send_ba_rjt()
1466  * fc_seq_assign() - Assign exchange and sequence for incoming request
1470  * On success, the sequence pointer will be returned and also in fr_seq(@fp).
1471  * A reference will be held on the exchange/sequence for the caller, which
1492  * @sp:    The sequence.
1507  * and the sequence.
1538 		sp = fr_seq(fp);	/* sequence will be held */  in fc_exch_recv_req()
1546 		 * The receive function may allocate a new sequence  in fc_exch_recv_req()
1548 		 * sequence after this.  in fc_exch_recv_req()
1566  *			     end is the originator of the sequence that is a
1636 	 * The sequence is held (has a refcnt) for us,  in fc_exch_recv_seq_resp()
1639 	 * The receive function may allocate a new sequence  in fc_exch_recv_seq_resp()
1641 	 * sequence after this.  in fc_exch_recv_seq_resp()
1660  * fc_exch_recv_resp() - Handler for a sequence where other end is
1661  *			 responding to our sequence
1669 	sp = fc_seq_lookup_orig(mp, fp);	/* doesn't hold sequence */  in fc_exch_recv_resp()
1684  * This response would be to an ABTS cancelling an exchange or sequence.
1757  * fc_exch_recv_bls() - Handler for a BLS sequence
1761  * The BLS frame is always a sequence initiated by the remote side.
1783 		 * A response to a sequence we initiated.  in fc_exch_recv_bls()
1823  * fc_seq_ls_acc() - Accept sequence with LS_ACC
1827  * originator will repeat the sequence.
1852  * fc_seq_ls_rjt() - Reject a sequence with ELS LS_RJT
1854  * @reason: The reason the sequence is being rejected
1858  * originator will repeat the sequence.
2095  * @sp:	 The sequence that the RRQ is on
2139  * fc_exch_seq_send() - Send a frame using a new exchange and sequence