xref: /openbmc/linux/drivers/scsi/libfc/fc_elsct.c (revision e8e0929d)
1 /*
2  * Copyright(c) 2008 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 /*
21  * Provide interface to send ELS/CT FC frames
22  */
23 
24 #include <asm/unaligned.h>
25 #include <scsi/fc/fc_gs.h>
26 #include <scsi/fc/fc_ns.h>
27 #include <scsi/fc/fc_els.h>
28 #include <scsi/libfc.h>
29 #include <scsi/fc_encode.h>
30 
31 /*
32  * fc_elsct_send - sends ELS/CT frame
33  */
34 static struct fc_seq *fc_elsct_send(struct fc_lport *lport,
35 				    u32 did,
36 				    struct fc_frame *fp,
37 				    unsigned int op,
38 				    void (*resp)(struct fc_seq *,
39 						 struct fc_frame *fp,
40 						 void *arg),
41 				    void *arg, u32 timer_msec)
42 {
43 	enum fc_rctl r_ctl;
44 	enum fc_fh_type fh_type;
45 	int rc;
46 
47 	/* ELS requests */
48 	if ((op >= ELS_LS_RJT) && (op <= ELS_AUTH_ELS))
49 		rc = fc_els_fill(lport, did, fp, op, &r_ctl, &fh_type);
50 	else {
51 		/* CT requests */
52 		rc = fc_ct_fill(lport, did, fp, op, &r_ctl, &fh_type);
53 		did = FC_FID_DIR_SERV;
54 	}
55 
56 	if (rc)
57 		return NULL;
58 
59 	fc_fill_fc_hdr(fp, r_ctl, did, fc_host_port_id(lport->host), fh_type,
60 		       FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
61 
62 	return lport->tt.exch_seq_send(lport, fp, resp, NULL, arg, timer_msec);
63 }
64 
65 int fc_elsct_init(struct fc_lport *lport)
66 {
67 	if (!lport->tt.elsct_send)
68 		lport->tt.elsct_send = fc_elsct_send;
69 
70 	return 0;
71 }
72 EXPORT_SYMBOL(fc_elsct_init);
73 
74 /**
75  * fc_els_resp_type() - return string describing ELS response for debug.
76  * @fp: frame pointer with possible error code.
77  */
78 const char *fc_els_resp_type(struct fc_frame *fp)
79 {
80 	const char *msg;
81 	if (IS_ERR(fp)) {
82 		switch (-PTR_ERR(fp)) {
83 		case FC_NO_ERR:
84 			msg = "response no error";
85 			break;
86 		case FC_EX_TIMEOUT:
87 			msg = "response timeout";
88 			break;
89 		case FC_EX_CLOSED:
90 			msg = "response closed";
91 			break;
92 		default:
93 			msg = "response unknown error";
94 			break;
95 		}
96 	} else {
97 		switch (fc_frame_payload_op(fp)) {
98 		case ELS_LS_ACC:
99 			msg = "accept";
100 			break;
101 		case ELS_LS_RJT:
102 			msg = "reject";
103 			break;
104 		default:
105 			msg = "response unknown ELS";
106 			break;
107 		}
108 	}
109 	return msg;
110 }
111