xref: /freebsd/sys/geom/geom_ctl.c (revision e8b59c3f5defe61b000d83fd915ba86eb5c77f4f)
1 /*-
2  * Copyright (c) 2002 Poul-Henning Kamp
3  * Copyright (c) 2002 Networks Associates Technology, Inc.
4  * All rights reserved.
5  *
6  * This software was developed for the FreeBSD Project by Poul-Henning Kamp
7  * and NAI Labs, the Security Research Division of Network Associates, Inc.
8  * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
9  * DARPA CHATS research program.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. The names of the authors may not be used to endorse or promote
20  *    products derived from this software without specific prior written
21  *    permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  *
35  * $FreeBSD$
36  */
37 
38 #include "opt_geom.h"
39 
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/kernel.h>
43 #include <sys/sysctl.h>
44 #include <sys/bio.h>
45 #include <sys/conf.h>
46 #include <sys/disk.h>
47 #include <sys/malloc.h>
48 #include <sys/sysctl.h>
49 
50 #include <sys/lock.h>
51 #include <sys/mutex.h>
52 #include <geom/geom.h>
53 #include <geom/geom_int.h>
54 
55 static g_access_t g_ctl_access;
56 static g_start_t g_ctl_start;
57 static void g_ctl_init(void);
58 static d_ioctl_t g_ctl_ioctl;
59 
60 struct g_class g_ctl_class = {
61 	"GEOMCTL",
62 	NULL,
63 	NULL,
64 	G_CLASS_INITIALIZER
65 };
66 
67 DECLARE_GEOM_CLASS_INIT(g_ctl_class, g_ctl, g_ctl_init);
68 
69 /*
70  * We cannot do create our geom.ctl geom/provider in g_ctl_init() because
71  * the event thread has to finish adding our class first and that doesn't
72  * happen until later.  We know however, that the events are processed in
73  * FIFO order, so scheduling g_ctl_init2() with g_call_me() is safe.
74  */
75 
76 static void
77 g_ctl_init2(void *p __unused)
78 {
79 	struct g_geom *gp;
80 	struct g_provider *pp;
81 
82 	g_topology_assert();
83 	gp = g_new_geomf(&g_ctl_class, "geom.ctl");
84 	gp->start = g_ctl_start;
85 	gp->access = g_ctl_access;
86 	pp = g_new_providerf(gp, "%s", gp->name);
87 	pp->sectorsize = 512;
88 	g_error_provider(pp, 0);
89 }
90 
91 static void
92 g_ctl_init(void)
93 {
94 	mtx_unlock(&Giant);
95 	g_add_class(&g_ctl_class);
96 	g_call_me(g_ctl_init2, NULL);
97 	mtx_lock(&Giant);
98 }
99 
100 /*
101  * We allow any kind of access.  Access control is handled at the devfs
102  * level.
103  */
104 
105 static int
106 g_ctl_access(struct g_provider *pp, int r, int w, int e)
107 {
108 	int error;
109 
110 	g_trace(G_T_ACCESS, "g_ctl_access(%s, %d, %d, %d)",
111 	    pp->name, r, w, e);
112 
113 	g_topology_assert();
114 	error = 0;
115 	return (error);
116 }
117 
118 static void
119 g_ctl_start(struct bio *bp)
120 {
121 	struct g_ioctl *gio;
122 	int error;
123 
124 	switch(bp->bio_cmd) {
125 	case BIO_DELETE:
126 	case BIO_READ:
127 	case BIO_WRITE:
128 		error = EOPNOTSUPP;
129 		break;
130 	case BIO_GETATTR:
131 	case BIO_SETATTR:
132 		if (strcmp(bp->bio_attribute, "GEOM::ioctl") ||
133 		    bp->bio_length != sizeof *gio) {
134 			error = EOPNOTSUPP;
135 			break;
136 		}
137 		gio = (struct g_ioctl *)bp->bio_data;
138 		gio->func = g_ctl_ioctl;
139 		error = EDIRIOCTL;
140 		break;
141 	default:
142 		error = EOPNOTSUPP;
143 		break;
144 	}
145 	g_io_deliver(bp, error);
146 	return;
147 }
148 
149 /*
150  * All the stuff above is really just needed to get to the stuff below
151  */
152 
153 static int
154 g_ctl_ioctl_configgeom(dev_t dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
155 {
156 	struct geomconfiggeom *gcp;
157 	struct g_configargs ga;
158 	int error;
159 
160 	error = 0;
161 	bzero(&ga, sizeof ga);
162 	gcp = (struct geomconfiggeom *)data;
163 	ga.class = g_idclass(&gcp->class);
164 	if (ga.class == NULL)
165 		return (EINVAL);
166 	if (ga.class->config == NULL)
167 		return (EOPNOTSUPP);
168 	ga.geom = g_idgeom(&gcp->geom);
169 	ga.provider = g_idprovider(&gcp->provider);
170 	ga.len = gcp->len;
171 	if (gcp->len > 64 * 1024)
172 		return (EINVAL);
173 	else if (gcp->len == 0) {
174 		ga.ptr = NULL;
175 	} else {
176 		ga.ptr = g_malloc(gcp->len, M_WAITOK);
177 		error = copyin(gcp->ptr, ga.ptr, gcp->len);
178 		if (error) {
179 			g_free(ga.ptr);
180 			return (error);
181 		}
182 	}
183 	ga.flag = gcp->flag;
184 	error = ga.class->config(&ga);
185 	if (gcp->len != 0)
186 		copyout(ga.ptr, gcp->ptr, gcp->len);	/* Ignore error */
187 	gcp->class.u.id = (uintptr_t)ga.class;
188 	gcp->class.len = 0;
189 	gcp->geom.u.id = (uintptr_t)ga.geom;
190 	gcp->geom.len = 0;
191 	gcp->provider.u.id = (uintptr_t)ga.provider;
192 	gcp->provider.len = 0;
193 	return(error);
194 }
195 
196 static int
197 g_ctl_ioctl(dev_t dev, u_long cmd, caddr_t data, int fflag, struct thread *td)
198 {
199 	int error;
200 
201 	DROP_GIANT();
202 	g_topology_lock();
203 	switch(cmd) {
204 	case GEOMCONFIGGEOM:
205 		error = g_ctl_ioctl_configgeom(dev, cmd, data, fflag, td);
206 		break;
207 	default:
208 		error = ENOTTY;
209 		break;
210 	}
211 	g_topology_unlock();
212 	PICKUP_GIANT();
213 	return (error);
214 
215 }
216