xref: /netbsd-src/sys/kern/kern_drvctl.c (revision 267197ec1eebfcb9810ea27a89625b6ddf68e3e7)
1 /* $NetBSD: kern_drvctl.c,v 1.14 2008/02/12 17:30:59 joerg 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 1.14 2008/02/12 17:30:59 joerg 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 pmdevbyname(int cmd, struct devpmargs *a)
58 {
59 	struct device *d;
60 
61 	if ((d = device_find_by_xname(a->devname)) == NULL)
62 		return ENXIO;
63 
64 	switch (cmd) {
65 	case DRVSUSPENDDEV:
66 		return pmf_device_recursive_suspend(d) ? 0 : EBUSY;
67 	case DRVRESUMEDEV:
68 		if (a->flags & DEVPM_F_SUBTREE)
69 			return pmf_device_resume_subtree(d) ? 0 : EBUSY;
70 		else
71 			return pmf_device_recursive_resume(d) ? 0 : EBUSY;
72 	default:
73 		return EPASSTHROUGH;
74 	}
75 }
76 
77 static int
78 listdevbyname(struct devlistargs *l)
79 {
80 	device_t d, child;
81 	int cnt = 0, idx, error;
82 
83 	if ((d = device_find_by_xname(l->l_devname)) == NULL)
84 		return ENXIO;
85 
86 	TAILQ_FOREACH(child, &alldevs, dv_list) {
87 		if (device_parent(child) != d)
88 			continue;
89 		idx = cnt++;
90 		if (l->l_childname == NULL || idx >= l->l_children)
91 			continue;
92 		error = copyoutstr(device_xname(child), l->l_childname[idx],
93 				sizeof(l->l_childname[idx]), NULL);
94 		if (error)
95 			return error;
96 	}
97 
98 	l->l_children = cnt;
99 	return 0;
100 }
101 
102 static int
103 detachdevbyname(const char *devname)
104 {
105 	struct device *d;
106 
107 	if ((d = device_find_by_xname(devname)) == NULL)
108 		return ENXIO;
109 
110 #ifndef XXXFULLRISK
111 	/*
112 	 * If the parent cannot be notified, it might keep
113 	 * pointers to the detached device.
114 	 * There might be a private notification mechanism,
115 	 * but better play save here.
116 	 */
117 	if (d->dv_parent && !d->dv_parent->dv_cfattach->ca_childdetached)
118 		return (ENOTSUP);
119 #endif
120 	return (config_detach(d, 0));
121 }
122 
123 static int
124 rescanbus(const char *busname, const char *ifattr,
125 	  int numlocators, const int *locators)
126 {
127 	int i, rc;
128 	struct device *d;
129 	const struct cfiattrdata * const *ap;
130 
131 	/* XXX there should be a way to get limits and defaults (per device)
132 	   from config generated data */
133 	int locs[MAXLOCATORS];
134 	for (i = 0; i < MAXLOCATORS; i++)
135 		locs[i] = -1;
136 
137 	for (i = 0; i < numlocators;i++)
138 		locs[i] = locators[i];
139 
140 	if ((d = device_find_by_xname(busname)) == NULL)
141 		return ENXIO;
142 
143 	/*
144 	 * must support rescan, and must have something
145 	 * to attach to
146 	 */
147 	if (!d->dv_cfattach->ca_rescan ||
148 	    !d->dv_cfdriver->cd_attrs)
149 		return (ENODEV);
150 
151 	/* allow to omit attribute if there is exactly one */
152 	if (!ifattr) {
153 		if (d->dv_cfdriver->cd_attrs[1])
154 			return (EINVAL);
155 		ifattr = d->dv_cfdriver->cd_attrs[0]->ci_name;
156 	} else {
157 		/* check for valid attribute passed */
158 		for (ap = d->dv_cfdriver->cd_attrs; *ap; ap++)
159 			if (!strcmp((*ap)->ci_name, ifattr))
160 				break;
161 		if (!*ap)
162 			return (EINVAL);
163 	}
164 
165 	rc = (*d->dv_cfattach->ca_rescan)(d, ifattr, locs);
166 	config_deferred(NULL);
167 	return rc;
168 }
169 
170 int
171 drvctlioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *p)
172 {
173 	int res;
174 	char *ifattr;
175 	int *locs;
176 
177 	switch (cmd) {
178 	case DRVSUSPENDDEV:
179 	case DRVRESUMEDEV:
180 #define d ((struct devpmargs *)data)
181 		res = pmdevbyname(cmd, d);
182 #undef d
183 		break;
184 	case DRVLISTDEV:
185 		res = listdevbyname((struct devlistargs *)data);
186 		break;
187 	case DRVDETACHDEV:
188 #define d ((struct devdetachargs *)data)
189 		res = detachdevbyname(d->devname);
190 #undef d
191 		break;
192 	case DRVRESCANBUS:
193 #define d ((struct devrescanargs *)data)
194 		d->busname[sizeof(d->busname) - 1] = '\0';
195 
196 		/* XXX better copyin? */
197 		if (d->ifattr[0]) {
198 			d->ifattr[sizeof(d->ifattr) - 1] = '\0';
199 			ifattr = d->ifattr;
200 		} else
201 			ifattr = 0;
202 
203 		if (d->numlocators) {
204 			if (d->numlocators > MAXLOCATORS)
205 				return (EINVAL);
206 			locs = malloc(d->numlocators * sizeof(int), M_DEVBUF,
207 				      M_WAITOK);
208 			res = copyin(d->locators, locs,
209 				     d->numlocators * sizeof(int));
210 			if (res) {
211 				free(locs, M_DEVBUF);
212 				return (res);
213 			}
214 		} else
215 			locs = 0;
216 		res = rescanbus(d->busname, ifattr, d->numlocators, locs);
217 		if (locs)
218 			free(locs, M_DEVBUF);
219 #undef d
220 		break;
221 	case DRVCTLCOMMAND:
222 	    	res = drvctl_command(p, (struct plistref *)data, cmd, flag);
223 	    	break;
224 	default:
225 		return (EPASSTHROUGH);
226 	}
227 	return (res);
228 }
229 
230 void
231 drvctlattach(int arg)
232 {
233 }
234 
235 /*****************************************************************************
236  * Driver control command processing engine
237  *****************************************************************************/
238 
239 static int
240 drvctl_command_get_properties(struct lwp *l,
241 			      prop_dictionary_t command_dict,
242 			      prop_dictionary_t results_dict)
243 {
244 	prop_dictionary_t args_dict;
245 	prop_string_t devname_string;
246 	device_t dev;
247 
248 	args_dict = prop_dictionary_get(command_dict, "drvctl-arguments");
249 	if (args_dict == NULL)
250 		return (EINVAL);
251 
252 	devname_string = prop_dictionary_get(args_dict, "device-name");
253 	if (devname_string == NULL)
254 		return (EINVAL);
255 
256 	TAILQ_FOREACH(dev, &alldevs, dv_list) {
257 		if (prop_string_equals_cstring(devname_string,
258 					       device_xname(dev)))
259 			break;
260 	}
261 
262 	if (dev == NULL)
263 		return (ESRCH);
264 
265 	prop_dictionary_set(results_dict, "drvctl-result-data",
266 			    device_properties(dev));
267 
268 	return (0);
269 }
270 
271 struct drvctl_command_desc {
272 	const char *dcd_name;		/* command name */
273 	int (*dcd_func)(struct lwp *,	/* handler function */
274 			prop_dictionary_t,
275 			prop_dictionary_t);
276 	int dcd_rw;			/* read or write required */
277 };
278 
279 static const struct drvctl_command_desc drvctl_command_table[] = {
280 	{ .dcd_name = "get-properties",
281 	  .dcd_func = drvctl_command_get_properties,
282 	  .dcd_rw   = FREAD,
283 	},
284 
285 	{ .dcd_name = NULL }
286 };
287 
288 static int
289 drvctl_command(struct lwp *l, struct plistref *pref, u_long ioctl_cmd,
290 	       int fflag)
291 {
292 	prop_dictionary_t command_dict, results_dict;
293 	prop_string_t command_string;
294 	const struct drvctl_command_desc *dcd;
295 	int error;
296 
297 	error = prop_dictionary_copyin_ioctl(pref, ioctl_cmd, &command_dict);
298 	if (error)
299 		return (error);
300 
301 	results_dict = prop_dictionary_create();
302 	if (results_dict == NULL) {
303 		prop_object_release(command_dict);
304 		return (ENOMEM);
305 	}
306 
307 	command_string = prop_dictionary_get(command_dict, "drvctl-command");
308 	if (command_string == NULL) {
309 		error = EINVAL;
310 		goto out;
311 	}
312 
313 	for (dcd = drvctl_command_table; dcd->dcd_name != NULL; dcd++) {
314 		if (prop_string_equals_cstring(command_string,
315 					       dcd->dcd_name))
316 			break;
317 	}
318 
319 	if (dcd->dcd_name == NULL) {
320 		error = EINVAL;
321 		goto out;
322 	}
323 
324 	if ((fflag & dcd->dcd_rw) == 0) {
325 		error = EPERM;
326 		goto out;
327 	}
328 
329 	error = (*dcd->dcd_func)(l, command_dict, results_dict);
330 
331 	prop_dictionary_set_int32(results_dict, "drvctl-error", error);
332 
333 	error = prop_dictionary_copyout_ioctl(pref, ioctl_cmd, results_dict);
334  out:
335 	prop_object_release(command_dict);
336 	prop_object_release(results_dict);
337 	return (error);
338 }
339