1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright(c) 2008 Intel Corporation. All rights reserved.
4 *
5 * Maintained at www.Open-FCoE.org
6 */
7
8/*
9 * Provide interface to send ELS/CT FC frames
10 */
11
12#include <linux/export.h>
13#include <asm/unaligned.h>
14#include <scsi/fc/fc_gs.h>
15#include <scsi/fc/fc_ns.h>
16#include <scsi/fc/fc_els.h>
17#include <scsi/libfc.h>
18#include "fc_encode.h"
19#include "fc_libfc.h"
20
21/**
22 * fc_elsct_send() - Send an ELS or CT frame
23 * @lport:	The local port to send the frame on
24 * @did:	The destination ID for the frame
25 * @fp:		The frame to be sent
26 * @op:		The operational code
27 * @resp:	The callback routine when the response is received
28 * @arg:	The argument to pass to the response callback routine
29 * @timer_msec: The timeout period for the frame (in msecs)
30 */
31struct fc_seq *fc_elsct_send(struct fc_lport *lport, u32 did,
32			     struct fc_frame *fp, unsigned int op,
33			     void (*resp)(struct fc_seq *,
34					  struct fc_frame *,
35					  void *),
36			     void *arg, u32 timer_msec)
37{
38	enum fc_rctl r_ctl;
39	enum fc_fh_type fh_type;
40	int rc;
41
42	/* ELS requests */
43	if ((op >= ELS_LS_RJT) && (op <= ELS_AUTH_ELS))
44		rc = fc_els_fill(lport, did, fp, op, &r_ctl, &fh_type);
45	else {
46		/* CT requests */
47		rc = fc_ct_fill(lport, did, fp, op, &r_ctl, &fh_type, &did);
48	}
49
50	if (rc) {
51		fc_frame_free(fp);
52		return NULL;
53	}
54
55	fc_fill_fc_hdr(fp, r_ctl, did, lport->port_id, fh_type,
56		       FC_FCTL_REQ, 0);
57
58	return fc_exch_seq_send(lport, fp, resp, NULL, arg, timer_msec);
59}
60EXPORT_SYMBOL(fc_elsct_send);
61
62/**
63 * fc_elsct_init() - Initialize the ELS/CT layer
64 * @lport: The local port to initialize the ELS/CT layer for
65 */
66int fc_elsct_init(struct fc_lport *lport)
67{
68	if (!lport->tt.elsct_send)
69		lport->tt.elsct_send = fc_elsct_send;
70
71	return 0;
72}
73EXPORT_SYMBOL(fc_elsct_init);
74
75/**
76 * fc_els_resp_type() - Return a string describing the ELS response
77 * @fp: The frame pointer or possible error code
78 */
79const char *fc_els_resp_type(struct fc_frame *fp)
80{
81	const char *msg;
82	struct fc_frame_header *fh;
83	struct fc_ct_hdr *ct;
84
85	if (IS_ERR(fp)) {
86		switch (-PTR_ERR(fp)) {
87		case FC_NO_ERR:
88			msg = "response no error";
89			break;
90		case FC_EX_TIMEOUT:
91			msg = "response timeout";
92			break;
93		case FC_EX_CLOSED:
94			msg = "response closed";
95			break;
96		default:
97			msg = "response unknown error";
98			break;
99		}
100	} else {
101		fh = fc_frame_header_get(fp);
102		switch (fh->fh_type) {
103		case FC_TYPE_ELS:
104			switch (fc_frame_payload_op(fp)) {
105			case ELS_LS_ACC:
106				msg = "accept";
107				break;
108			case ELS_LS_RJT:
109				msg = "reject";
110				break;
111			default:
112				msg = "response unknown ELS";
113				break;
114			}
115			break;
116		case FC_TYPE_CT:
117			ct = fc_frame_payload_get(fp, sizeof(*ct));
118			if (ct) {
119				switch (ntohs(ct->ct_cmd)) {
120				case FC_FS_ACC:
121					msg = "CT accept";
122					break;
123				case FC_FS_RJT:
124					msg = "CT reject";
125					break;
126				default:
127					msg = "response unknown CT";
128					break;
129				}
130			} else {
131				msg = "short CT response";
132			}
133			break;
134		default:
135			msg = "response not ELS or CT";
136			break;
137		}
138	}
139	return msg;
140}
141