ctl_backend.c revision 288795 
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 288795 2015-10-05 10:58:41Z 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 = control_softc;
69	struct ctl_backend_driver *be_tmp;
70
71	mtx_lock(&softc->ctl_lock);
72	/*
73	 * Sanity check, make sure this isn't a duplicate registration.
74	 */
75	STAILQ_FOREACH(be_tmp, &softc->be_list, links) {
76		if (strcmp(be_tmp->name, be->name) == 0) {
77			mtx_unlock(&softc->ctl_lock);
78			return (-1);
79		}
80	}
81	mtx_unlock(&softc->ctl_lock);
82
83	/*
84	 * Call the backend's initialization routine.
85	 */
86	be->init();
87
88	mtx_lock(&softc->ctl_lock);
89
90	STAILQ_INSERT_TAIL(&softc->be_list, be, links);
91
92	softc->num_backends++;
93
94	/*
95	 * Don't want to increment the usage count for internal consumers,
96	 * we won't be able to unload otherwise.
97	 */
98	/* XXX KDM find a substitute for this? */
99#if 0
100	if ((be->flags & CTL_BE_FLAG_INTERNAL) == 0)
101		MOD_INC_USE_COUNT;
102#endif
103
104#ifdef CS_BE_CONFIG_MOVE_DONE_IS_NOT_USED
105	be->config_move_done = ctl_config_move_done;
106#endif
107	/* XXX KDM fix this! */
108	be->num_luns = 0;
109#if 0
110	atomic_set(&be->num_luns, 0);
111#endif
112
113	mtx_unlock(&softc->ctl_lock);
114
115	return (0);
116}
117
118int
119ctl_backend_deregister(struct ctl_backend_driver *be)
120{
121	struct ctl_softc *softc = control_softc;
122
123	mtx_lock(&softc->ctl_lock);
124
125#if 0
126	if (atomic_read(&be->num_luns) != 0) {
127#endif
128	/* XXX KDM fix this! */
129	if (be->num_luns != 0) {
130		mtx_unlock(&softc->ctl_lock);
131		return (-1);
132	}
133
134	STAILQ_REMOVE(&softc->be_list, be, ctl_backend_driver, links);
135
136	softc->num_backends--;
137
138	/* XXX KDM find a substitute for this? */
139#if 0
140	if ((be->flags & CTL_BE_FLAG_INTERNAL) == 0)
141		MOD_DEC_USE_COUNT;
142#endif
143
144	mtx_unlock(&softc->ctl_lock);
145
146	return (0);
147}
148
149struct ctl_backend_driver *
150ctl_backend_find(char *backend_name)
151{
152	struct ctl_softc *softc = control_softc;
153	struct ctl_backend_driver *be_tmp;
154
155	mtx_lock(&softc->ctl_lock);
156	STAILQ_FOREACH(be_tmp, &softc->be_list, links) {
157		if (strcmp(be_tmp->name, backend_name) == 0) {
158			mtx_unlock(&softc->ctl_lock);
159			return (be_tmp);
160		}
161	}
162	mtx_unlock(&softc->ctl_lock);
163
164	return (NULL);
165}
166
167void
168ctl_init_opts(ctl_options_t *opts, int num_args, struct ctl_be_arg *args)
169{
170	struct ctl_option *opt;
171	int i;
172
173	STAILQ_INIT(opts);
174	for (i = 0; i < num_args; i++) {
175		if ((args[i].flags & CTL_BEARG_RD) == 0)
176			continue;
177		if ((args[i].flags & CTL_BEARG_ASCII) == 0)
178			continue;
179		opt = malloc(sizeof(*opt), M_CTL, M_WAITOK);
180		opt->name = strdup(args[i].kname, M_CTL);
181		opt->value = strdup(args[i].kvalue, M_CTL);
182		STAILQ_INSERT_TAIL(opts, opt, links);
183	}
184}
185
186void
187ctl_update_opts(ctl_options_t *opts, int num_args, struct ctl_be_arg *args)
188{
189	struct ctl_option *opt;
190	int i;
191
192	for (i = 0; i < num_args; i++) {
193		if ((args[i].flags & CTL_BEARG_RD) == 0)
194			continue;
195		if ((args[i].flags & CTL_BEARG_ASCII) == 0)
196			continue;
197		STAILQ_FOREACH(opt, opts, links) {
198			if (strcmp(opt->name, args[i].kname) == 0)
199				break;
200		}
201		if (args[i].kvalue != NULL &&
202		    ((char *)args[i].kvalue)[0] != 0) {
203			if (opt) {
204				free(opt->value, M_CTL);
205				opt->value = strdup(args[i].kvalue, M_CTL);
206			} else {
207				opt = malloc(sizeof(*opt), M_CTL, M_WAITOK);
208				opt->name = strdup(args[i].kname, M_CTL);
209				opt->value = strdup(args[i].kvalue, M_CTL);
210				STAILQ_INSERT_TAIL(opts, opt, links);
211			}
212		} else if (opt) {
213			STAILQ_REMOVE(opts, opt, ctl_option, links);
214			free(opt->name, M_CTL);
215			free(opt->value, M_CTL);
216			free(opt, M_CTL);
217		}
218	}
219}
220
221void
222ctl_free_opts(ctl_options_t *opts)
223{
224	struct ctl_option *opt;
225
226	while ((opt = STAILQ_FIRST(opts)) != NULL) {
227		STAILQ_REMOVE_HEAD(opts, links);
228		free(opt->name, M_CTL);
229		free(opt->value, M_CTL);
230		free(opt, M_CTL);
231	}
232}
233
234char *
235ctl_get_opt(ctl_options_t *opts, const char *name)
236{
237	struct ctl_option *opt;
238
239	STAILQ_FOREACH(opt, opts, links) {
240		if (strcmp(opt->name, name) == 0) {
241			return (opt->value);
242		}
243	}
244	return (NULL);
245}
246