ctl_backend.c revision 288719 
1/*-
2 * Copyright (c) 2003 Silicon Graphics International Corp.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions, and the following disclaimer,
10 *    without modification.
11 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
12 *    substantially similar to the "NO WARRANTY" disclaimer below
13 *    ("Disclaimer") and any redistribution must be conditioned upon
14 *    including a substantially similar Disclaimer requirement for further
15 *    binary redistribution.
16 *
17 * NO WARRANTY
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
26 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
27 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 * POSSIBILITY OF SUCH DAMAGES.
29 *
30 * $Id: //depot/users/kenm/FreeBSD-test2/sys/cam/ctl/ctl_backend.c#3 $
31 */
32/*
33 * CTL backend driver registration routines
34 *
35 * Author: Ken Merry <ken@FreeBSD.org>
36 */
37
38#include <sys/cdefs.h>
39__FBSDID("$FreeBSD: stable/10/sys/cam/ctl/ctl_backend.c 288719 2015-10-05 08:42:43Z mav $");
40
41#include <sys/param.h>
42#include <sys/systm.h>
43#include <sys/kernel.h>
44#include <sys/types.h>
45#include <sys/malloc.h>
46#include <sys/lock.h>
47#include <sys/mutex.h>
48#include <sys/condvar.h>
49#include <sys/queue.h>
50#include <sys/sysctl.h>
51
52#include <cam/scsi/scsi_all.h>
53#include <cam/scsi/scsi_da.h>
54#include <cam/ctl/ctl_io.h>
55#include <cam/ctl/ctl.h>
56#include <cam/ctl/ctl_frontend.h>
57#include <cam/ctl/ctl_backend.h>
58#include <cam/ctl/ctl_ioctl.h>
59#include <cam/ctl/ctl_ha.h>
60#include <cam/ctl/ctl_private.h>
61#include <cam/ctl/ctl_debug.h>
62
63extern struct ctl_softc *control_softc;
64
65int
66ctl_backend_register(struct ctl_backend_driver *be)
67{
68	struct ctl_softc *softc;
69	struct ctl_backend_driver *be_tmp;
70
71	softc = control_softc;
72
73	mtx_lock(&softc->ctl_lock);
74	/*
75	 * Sanity check, make sure this isn't a duplicate registration.
76	 */
77	STAILQ_FOREACH(be_tmp, &softc->be_list, links) {
78		if (strcmp(be_tmp->name, be->name) == 0) {
79			mtx_unlock(&softc->ctl_lock);
80			return (-1);
81		}
82	}
83	mtx_unlock(&softc->ctl_lock);
84
85	/*
86	 * Call the backend's initialization routine.
87	 */
88	be->init();
89
90	mtx_lock(&softc->ctl_lock);
91
92	STAILQ_INSERT_TAIL(&softc->be_list, be, links);
93
94	softc->num_backends++;
95
96	/*
97	 * Don't want to increment the usage count for internal consumers,
98	 * we won't be able to unload otherwise.
99	 */
100	/* XXX KDM find a substitute for this? */
101#if 0
102	if ((be->flags & CTL_BE_FLAG_INTERNAL) == 0)
103		MOD_INC_USE_COUNT;
104#endif
105
106#ifdef CS_BE_CONFIG_MOVE_DONE_IS_NOT_USED
107	be->config_move_done = ctl_config_move_done;
108#endif
109	/* XXX KDM fix this! */
110	be->num_luns = 0;
111#if 0
112	atomic_set(&be->num_luns, 0);
113#endif
114
115	mtx_unlock(&softc->ctl_lock);
116
117	return (0);
118}
119
120int
121ctl_backend_deregister(struct ctl_backend_driver *be)
122{
123	struct ctl_softc *softc;
124
125	softc = control_softc;
126
127	mtx_lock(&softc->ctl_lock);
128
129#if 0
130	if (atomic_read(&be->num_luns) != 0) {
131#endif
132	/* XXX KDM fix this! */
133	if (be->num_luns != 0) {
134		mtx_unlock(&softc->ctl_lock);
135		return (-1);
136	}
137
138	STAILQ_REMOVE(&softc->be_list, be, ctl_backend_driver, links);
139
140	softc->num_backends--;
141
142	/* XXX KDM find a substitute for this? */
143#if 0
144	if ((be->flags & CTL_BE_FLAG_INTERNAL) == 0)
145		MOD_DEC_USE_COUNT;
146#endif
147
148	mtx_unlock(&softc->ctl_lock);
149
150	return (0);
151}
152
153struct ctl_backend_driver *
154ctl_backend_find(char *backend_name)
155{
156	struct ctl_softc *softc;
157	struct ctl_backend_driver *be_tmp;
158
159	softc = control_softc;
160
161	mtx_lock(&softc->ctl_lock);
162
163	STAILQ_FOREACH(be_tmp, &softc->be_list, links) {
164		if (strcmp(be_tmp->name, backend_name) == 0) {
165			mtx_unlock(&softc->ctl_lock);
166			return (be_tmp);
167		}
168	}
169
170	mtx_unlock(&softc->ctl_lock);
171
172	return (NULL);
173}
174
175void
176ctl_init_opts(ctl_options_t *opts, int num_args, struct ctl_be_arg *args)
177{
178	struct ctl_option *opt;
179	int i;
180
181	STAILQ_INIT(opts);
182	for (i = 0; i < num_args; i++) {
183		if ((args[i].flags & CTL_BEARG_RD) == 0)
184			continue;
185		if ((args[i].flags & CTL_BEARG_ASCII) == 0)
186			continue;
187		opt = malloc(sizeof(*opt), M_CTL, M_WAITOK);
188		opt->name = malloc(strlen(args[i].kname) + 1, M_CTL, M_WAITOK);
189		strcpy(opt->name, args[i].kname);
190		opt->value = malloc(strlen(args[i].kvalue) + 1, M_CTL, M_WAITOK);
191		strcpy(opt->value, args[i].kvalue);
192		STAILQ_INSERT_TAIL(opts, opt, links);
193	}
194}
195
196void
197ctl_free_opts(ctl_options_t *opts)
198{
199	struct ctl_option *opt;
200
201	while ((opt = STAILQ_FIRST(opts)) != NULL) {
202		STAILQ_REMOVE_HEAD(opts, links);
203		free(opt->name, M_CTL);
204		free(opt->value, M_CTL);
205		free(opt, M_CTL);
206	}
207}
208
209char *
210ctl_get_opt(ctl_options_t *opts, const char *name)
211{
212	struct ctl_option *opt;
213
214	STAILQ_FOREACH(opt, opts, links) {
215		if (strcmp(opt->name, name) == 0) {
216			return (opt->value);
217		}
218	}
219	return (NULL);
220}
221