xref: /freebsd/sys/cam/ctl/ctl_backend.c (revision 640235e2c2ba32947f7c59d168437ffa1280f1e6)
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("$FreeBSD$");
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 
63 extern struct ctl_softc *control_softc;
64 
65 int
66 ctl_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 
118 int
119 ctl_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 
149 struct ctl_backend_driver *
150 ctl_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 
167 void
168 ctl_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 
186 void
187 ctl_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 
221 void
222 ctl_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 
234 char *
235 ctl_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