xref: /netbsd-src/sys/kern/kern_drvctl.c (revision ce2c90c7c172d95d2402a5b3d96d8f8e6d138a21)
1 /* $NetBSD: kern_drvctl.c,v 1.7 2006/10/12 04:29:37 thorpej Exp $ */
2 
3 /*
4  * Copyright (c) 2004
5  * 	Matthias Drochner.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions, and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: kern_drvctl.c,v 1.7 2006/10/12 04:29:37 thorpej Exp $");
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/kernel.h>
35 #include <sys/conf.h>
36 #include <sys/device.h>
37 #include <sys/event.h>
38 #include <sys/malloc.h>
39 #include <sys/ioctl.h>
40 #include <sys/fcntl.h>
41 #include <sys/drvctlio.h>
42 
43 dev_type_ioctl(drvctlioctl);
44 
45 const struct cdevsw drvctl_cdevsw = {
46 	nullopen, nullclose, nullread, nullwrite, drvctlioctl,
47 	nostop, notty, nopoll, nommap, nokqfilter, D_OTHER
48 };
49 
50 void drvctlattach(int);
51 
52 #define MAXLOCATORS 100
53 
54 static int drvctl_command(struct lwp *, struct plistref *, u_long, int flag);
55 
56 static int
57 detachdevbyname(const char *devname)
58 {
59 	struct device *d;
60 
61 	TAILQ_FOREACH(d, &alldevs, dv_list) {
62 		if (!strcmp(devname, d->dv_xname)) {
63 #ifndef XXXFULLRISK
64 			/*
65 			 * If the parent cannot be notified, it might keep
66 			 * pointers to the detached device.
67 			 * There might be a private notification mechanism,
68 			 * but better play save here.
69 			 */
70 			if (d->dv_parent &&
71 			    !d->dv_parent->dv_cfattach->ca_childdetached)
72 				return (ENOTSUP);
73 #endif
74 			return (config_detach(d, 0));
75 		}
76 	}
77 
78 	return (ENXIO);
79 }
80 
81 static int
82 rescanbus(const char *busname, const char *ifattr,
83 	  int numlocators, const int *locators)
84 {
85 	int i;
86 	struct device *d;
87 	const struct cfiattrdata * const *ap;
88 
89 	/* XXX there should be a way to get limits and defaults (per device)
90 	   from config generated data */
91 	int locs[MAXLOCATORS];
92 	for (i = 0; i < MAXLOCATORS; i++)
93 		locs[i] = -1;
94 
95 	for (i = 0; i < numlocators;i++)
96 		locs[i] = locators[i];
97 
98 	TAILQ_FOREACH(d, &alldevs, dv_list) {
99 		if (!strcmp(busname, d->dv_xname)) {
100 			/*
101 			 * must support rescan, and must have something
102 			 * to attach to
103 			 */
104 			if (!d->dv_cfattach->ca_rescan ||
105 			    !d->dv_cfdriver->cd_attrs)
106 				return (ENODEV);
107 
108 			/* allow to omit attribute if there is exactly one */
109 			if (!ifattr) {
110 				if (d->dv_cfdriver->cd_attrs[1])
111 					return (EINVAL);
112 				ifattr = d->dv_cfdriver->cd_attrs[0]->ci_name;
113 			} else {
114 				/* check for valid attribute passed */
115 				for (ap = d->dv_cfdriver->cd_attrs; *ap; ap++)
116 					if (!strcmp((*ap)->ci_name, ifattr))
117 						break;
118 				if (!*ap)
119 					return (EINVAL);
120 			}
121 
122 			return (*d->dv_cfattach->ca_rescan)(d, ifattr, locs);
123 		}
124 	}
125 
126 	return (ENXIO);
127 }
128 
129 int
130 drvctlioctl(dev_t dev __unused, u_long cmd, caddr_t data, int flag,
131 	    struct lwp *p)
132 {
133 	int res;
134 	char *ifattr;
135 	int *locs;
136 
137 	switch (cmd) {
138 	case DRVDETACHDEV:
139 #define d ((struct devdetachargs *)data)
140 		res = detachdevbyname(d->devname);
141 #undef d
142 		break;
143 	case DRVRESCANBUS:
144 #define d ((struct devrescanargs *)data)
145 		d->busname[sizeof(d->busname) - 1] = '\0';
146 
147 		/* XXX better copyin? */
148 		if (d->ifattr[0]) {
149 			d->ifattr[sizeof(d->ifattr) - 1] = '\0';
150 			ifattr = d->ifattr;
151 		} else
152 			ifattr = 0;
153 
154 		if (d->numlocators) {
155 			if (d->numlocators > MAXLOCATORS)
156 				return (EINVAL);
157 			locs = malloc(d->numlocators * sizeof(int), M_DEVBUF,
158 				      M_WAITOK);
159 			res = copyin(d->locators, locs,
160 				     d->numlocators * sizeof(int));
161 			if (res)
162 				return (res);
163 		} else
164 			locs = 0;
165 		res = rescanbus(d->busname, ifattr, d->numlocators, locs);
166 		if (locs)
167 			free(locs, M_DEVBUF);
168 #undef d
169 		break;
170 	case DRVCTLCOMMAND:
171 	    	res = drvctl_command(p, (struct plistref *)data, cmd, flag);
172 	    	break;
173 	default:
174 		return (EPASSTHROUGH);
175 	}
176 	return (res);
177 }
178 
179 void
180 drvctlattach(int arg __unused)
181 {
182 }
183 
184 /*****************************************************************************
185  * Driver control command processing engine
186  *****************************************************************************/
187 
188 static int
189 drvctl_command_get_properties(struct lwp *l __unused,
190 			      prop_dictionary_t command_dict,
191 			      prop_dictionary_t results_dict)
192 {
193 	prop_dictionary_t args_dict;
194 	prop_string_t devname_string;
195 	device_t dev;
196 
197 	args_dict = prop_dictionary_get(command_dict, "drvctl-arguments");
198 	if (args_dict == NULL)
199 		return (EINVAL);
200 
201 	devname_string = prop_dictionary_get(args_dict, "device-name");
202 	if (devname_string == NULL)
203 		return (EINVAL);
204 
205 	TAILQ_FOREACH(dev, &alldevs, dv_list) {
206 		if (prop_string_equals_cstring(devname_string,
207 					       device_xname(dev)))
208 			break;
209 	}
210 
211 	if (dev == NULL)
212 		return (ESRCH);
213 
214 	prop_dictionary_set(results_dict, "drvctl-result-data",
215 			    device_properties(dev));
216 
217 	return (0);
218 }
219 
220 struct drvctl_command_desc {
221 	const char *dcd_name;		/* command name */
222 	int (*dcd_func)(struct lwp *,	/* handler function */
223 			prop_dictionary_t,
224 			prop_dictionary_t);
225 	int dcd_rw;			/* read or write required */
226 };
227 
228 static const struct drvctl_command_desc drvctl_command_table[] = {
229 	{ .dcd_name = "get-properties",
230 	  .dcd_func = drvctl_command_get_properties,
231 	  .dcd_rw   = FREAD,
232 	},
233 
234 	{ .dcd_name = NULL }
235 };
236 
237 static int
238 drvctl_command(struct lwp *l, struct plistref *pref, u_long ioctl_cmd,
239 	       int fflag)
240 {
241 	prop_dictionary_t command_dict, results_dict;
242 	prop_string_t command_string;
243 	prop_number_t error_number;
244 	const struct drvctl_command_desc *dcd;
245 	int error;
246 
247 	error = prop_dictionary_copyin_ioctl(pref, ioctl_cmd, &command_dict);
248 	if (error)
249 		return (error);
250 
251 	results_dict = prop_dictionary_create();
252 	if (results_dict == NULL) {
253 		prop_object_release(command_dict);
254 		return (ENOMEM);
255 	}
256 
257 	command_string = prop_dictionary_get(command_dict, "drvctl-command");
258 	if (command_string == NULL) {
259 		error = EINVAL;
260 		goto out;
261 	}
262 
263 	for (dcd = drvctl_command_table; dcd->dcd_name != NULL; dcd++) {
264 		if (prop_string_equals_cstring(command_string,
265 					       dcd->dcd_name))
266 			break;
267 	}
268 
269 	if (dcd->dcd_name == NULL) {
270 		error = EINVAL;
271 		goto out;
272 	}
273 
274 	if ((fflag & dcd->dcd_rw) == 0) {
275 		error = EPERM;
276 		goto out;
277 	}
278 
279 	error = (*dcd->dcd_func)(l, command_dict, results_dict);
280 
281 	error_number = prop_number_create_integer(error);
282 	prop_dictionary_set(results_dict, "drvctl-error", error_number);
283 	prop_object_release(error_number);
284 
285 	error = prop_dictionary_copyout_ioctl(pref, ioctl_cmd, results_dict);
286  out:
287 	prop_object_release(command_dict);
288 	prop_object_release(results_dict);
289 	return (error);
290 }
291