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 <linux/export.h>
25#include <asm/unaligned.h>
26#include <scsi/fc/fc_gs.h>
27#include <scsi/fc/fc_ns.h>
28#include <scsi/fc/fc_els.h>
29#include <scsi/libfc.h>
30#include <scsi/fc_encode.h>
31#include "fc_libfc.h"
32
33/**
34 * fc_elsct_send() - Send an ELS or CT frame
35 * @lport:	The local port to send the frame on
36 * @did:	The destination ID for the frame
37 * @fp:		The frame to be sent
38 * @op:		The operational code
39 * @resp:	The callback routine when the response is received
40 * @arg:	The argument to pass to the response callback routine
41 * @timer_msec: The timeout period for the frame (in msecs)
42 */
43struct fc_seq *fc_elsct_send(struct fc_lport *lport, u32 did,
44			     struct fc_frame *fp, unsigned int op,
45			     void (*resp)(struct fc_seq *,
46					  struct fc_frame *,
47					  void *),
48			     void *arg, u32 timer_msec)
49{
50	enum fc_rctl r_ctl;
51	enum fc_fh_type fh_type;
52	int rc;
53
54	/* ELS requests */
55	if ((op >= ELS_LS_RJT) && (op <= ELS_AUTH_ELS))
56		rc = fc_els_fill(lport, did, fp, op, &r_ctl, &fh_type);
57	else {
58		/* CT requests */
59		rc = fc_ct_fill(lport, did, fp, op, &r_ctl, &fh_type, &did);
60	}
61
62	if (rc) {
63		fc_frame_free(fp);
64		return NULL;
65	}
66
67	fc_fill_fc_hdr(fp, r_ctl, did, lport->port_id, fh_type,
68		       FC_FCTL_REQ, 0);
69
70	return lport->tt.exch_seq_send(lport, fp, resp, NULL, arg, timer_msec);
71}
72EXPORT_SYMBOL(fc_elsct_send);
73
74/**
75 * fc_elsct_init() - Initialize the ELS/CT layer
76 * @lport: The local port to initialize the ELS/CT layer for
77 */
78int fc_elsct_init(struct fc_lport *lport)
79{
80	if (!lport->tt.elsct_send)
81		lport->tt.elsct_send = fc_elsct_send;
82
83	return 0;
84}
85EXPORT_SYMBOL(fc_elsct_init);
86
87/**
88 * fc_els_resp_type() - Return a string describing the ELS response
89 * @fp: The frame pointer or possible error code
90 */
91const char *fc_els_resp_type(struct fc_frame *fp)
92{
93	const char *msg;
94	struct fc_frame_header *fh;
95	struct fc_ct_hdr *ct;
96
97	if (IS_ERR(fp)) {
98		switch (-PTR_ERR(fp)) {
99		case FC_NO_ERR:
100			msg = "response no error";
101			break;
102		case FC_EX_TIMEOUT:
103			msg = "response timeout";
104			break;
105		case FC_EX_CLOSED:
106			msg = "response closed";
107			break;
108		default:
109			msg = "response unknown error";
110			break;
111		}
112	} else {
113		fh = fc_frame_header_get(fp);
114		switch (fh->fh_type) {
115		case FC_TYPE_ELS:
116			switch (fc_frame_payload_op(fp)) {
117			case ELS_LS_ACC:
118				msg = "accept";
119				break;
120			case ELS_LS_RJT:
121				msg = "reject";
122				break;
123			default:
124				msg = "response unknown ELS";
125				break;
126			}
127			break;
128		case FC_TYPE_CT:
129			ct = fc_frame_payload_get(fp, sizeof(*ct));
130			if (ct) {
131				switch (ntohs(ct->ct_cmd)) {
132				case FC_FS_ACC:
133					msg = "CT accept";
134					break;
135				case FC_FS_RJT:
136					msg = "CT reject";
137					break;
138				default:
139					msg = "response unknown CT";
140					break;
141				}
142			} else {
143				msg = "short CT response";
144			}
145			break;
146		default:
147			msg = "response not ELS or CT";
148			break;
149		}
150	}
151	return msg;
152}
153