xref: /freebsd/lib/libdevctl/devctl.c (revision 4d846d26)
1 /*-
2  * Copyright (c) 2014 John Baldwin <jhb@FreeBSD.org>
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23  * SUCH DAMAGE.
24  */
25 
26 #include <sys/cdefs.h>
27 __FBSDID("$FreeBSD$");
28 
29 #include <sys/types.h>
30 #include <sys/bus.h>
31 #include <errno.h>
32 #include <fcntl.h>
33 #include <stdlib.h>
34 #include <string.h>
35 #include "devctl.h"
36 
37 static int
38 devctl_request(u_long cmd, struct devreq *req)
39 {
40 	static int devctl2_fd = -1;
41 
42 	if (devctl2_fd == -1) {
43 		devctl2_fd = open("/dev/devctl2", O_RDONLY);
44 		if (devctl2_fd == -1)
45 			return (-1);
46 	}
47 	return (ioctl(devctl2_fd, cmd, req));
48 }
49 
50 static int
51 devctl_simple_request(u_long cmd, const char *name, int flags)
52 {
53 	struct devreq req;
54 
55 	memset(&req, 0, sizeof(req));
56 	if (strlcpy(req.dr_name, name, sizeof(req.dr_name)) >=
57 	    sizeof(req.dr_name)) {
58 		errno = EINVAL;
59 		return (-1);
60 	}
61 	req.dr_flags = flags;
62 	return (devctl_request(cmd, &req));
63 }
64 
65 int
66 devctl_attach(const char *device)
67 {
68 
69 	return (devctl_simple_request(DEV_ATTACH, device, 0));
70 }
71 
72 int
73 devctl_detach(const char *device, bool force)
74 {
75 
76 	return (devctl_simple_request(DEV_DETACH, device, force ?
77 	    DEVF_FORCE_DETACH : 0));
78 }
79 
80 int
81 devctl_enable(const char *device)
82 {
83 
84 	return (devctl_simple_request(DEV_ENABLE, device, 0));
85 }
86 
87 int
88 devctl_disable(const char *device, bool force_detach)
89 {
90 
91 	return (devctl_simple_request(DEV_DISABLE, device, force_detach ?
92 	    DEVF_FORCE_DETACH : 0));
93 }
94 
95 int
96 devctl_suspend(const char *device)
97 {
98 
99 	return (devctl_simple_request(DEV_SUSPEND, device, 0));
100 }
101 
102 int
103 devctl_resume(const char *device)
104 {
105 
106 	return (devctl_simple_request(DEV_RESUME, device, 0));
107 }
108 
109 int
110 devctl_set_driver(const char *device, const char *driver, bool force)
111 {
112 	struct devreq req;
113 
114 	memset(&req, 0, sizeof(req));
115 	if (strlcpy(req.dr_name, device, sizeof(req.dr_name)) >=
116 	    sizeof(req.dr_name)) {
117 		errno = EINVAL;
118 		return (-1);
119 	}
120 	req.dr_data = __DECONST(char *, driver);
121 	if (force)
122 		req.dr_flags |= DEVF_SET_DRIVER_DETACH;
123 	return (devctl_request(DEV_SET_DRIVER, &req));
124 }
125 
126 int
127 devctl_clear_driver(const char *device, bool force)
128 {
129 
130 	return (devctl_simple_request(DEV_CLEAR_DRIVER, device, force ?
131 	    DEVF_CLEAR_DRIVER_DETACH : 0));
132 }
133 
134 int
135 devctl_rescan(const char *device)
136 {
137 
138 	return (devctl_simple_request(DEV_RESCAN, device, 0));
139 }
140 
141 int
142 devctl_delete(const char *device, bool force)
143 {
144 
145 	return (devctl_simple_request(DEV_DELETE, device, force ?
146 	    DEVF_FORCE_DELETE : 0));
147 }
148 
149 int
150 devctl_freeze(void)
151 {
152 
153 	return (devctl_simple_request(DEV_FREEZE, "", 0));
154 }
155 
156 int
157 devctl_thaw(void)
158 {
159 
160 	return (devctl_simple_request(DEV_THAW, "", 0));
161 }
162 
163 int
164 devctl_reset(const char *device, bool detach)
165 {
166 
167 	return (devctl_simple_request(DEV_RESET, device, detach ?
168 	    DEVF_RESET_DETACH : 0));
169 }
170 
171 #define BUFLEN 1024
172 
173 int
174 devctl_getpath(const char *device, const char *locator, char **buffer)
175 {
176 	struct devreq req;
177 	int serrno;
178 
179 	memset(&req, 0, sizeof(req));
180 	if (strlcpy(req.dr_name, device, sizeof(req.dr_name)) >=
181 	    sizeof(req.dr_name)) {
182 		errno = EINVAL;
183 		*buffer = NULL;
184 		return (-1);
185 	}
186 
187 	/*
188 	 * Maybe do the request twice. Once to get the length, and then again to
189 	 * get the string if BUFLEN bytes is insufficient.
190 	 */
191 	req.dr_flags = 0;
192 	req.dr_buffer.length = BUFLEN;
193 again:
194 	req.dr_buffer.buffer = malloc(req.dr_buffer.length);
195 	strlcpy(req.dr_buffer.buffer, locator, req.dr_buffer.length);
196 	if (devctl_request(DEV_GET_PATH, &req) == 0) {
197 		*buffer = req.dr_buffer.buffer;
198 		return (0);
199 	}
200 	if (errno == ENAMETOOLONG && req.dr_buffer.length != BUFLEN) {
201 		free(req.dr_buffer.buffer);
202 		goto again;
203 	}
204 	serrno = errno;
205 	free(req.dr_buffer.buffer);
206 	errno = serrno;
207 	*buffer = NULL;
208 	return (-1);
209 }
210