xref: /freebsd/lib/libdevctl/devctl.c (revision 1da7f3f6f72b2245e458fc7195733268ae4a1136)
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/types.h>
27 #include <sys/bus.h>
28 #include <errno.h>
29 #include <fcntl.h>
30 #include <stdlib.h>
31 #include <string.h>
32 #include "devctl.h"
33 
34 static int
35 devctl_request(u_long cmd, struct devreq *req)
36 {
37 	static int devctl2_fd = -1;
38 
39 	if (devctl2_fd == -1) {
40 		devctl2_fd = open("/dev/devctl2", O_RDONLY);
41 		if (devctl2_fd == -1)
42 			return (-1);
43 	}
44 	return (ioctl(devctl2_fd, cmd, req));
45 }
46 
47 static int
48 devctl_simple_request(u_long cmd, const char *name, int flags)
49 {
50 	struct devreq req;
51 
52 	memset(&req, 0, sizeof(req));
53 	if (strlcpy(req.dr_name, name, sizeof(req.dr_name)) >=
54 	    sizeof(req.dr_name)) {
55 		errno = EINVAL;
56 		return (-1);
57 	}
58 	req.dr_flags = flags;
59 	return (devctl_request(cmd, &req));
60 }
61 
62 int
63 devctl_attach(const char *device)
64 {
65 
66 	return (devctl_simple_request(DEV_ATTACH, device, 0));
67 }
68 
69 int
70 devctl_detach(const char *device, bool force)
71 {
72 
73 	return (devctl_simple_request(DEV_DETACH, device, force ?
74 	    DEVF_FORCE_DETACH : 0));
75 }
76 
77 int
78 devctl_enable(const char *device)
79 {
80 
81 	return (devctl_simple_request(DEV_ENABLE, device, 0));
82 }
83 
84 int
85 devctl_disable(const char *device, bool force_detach)
86 {
87 
88 	return (devctl_simple_request(DEV_DISABLE, device, force_detach ?
89 	    DEVF_FORCE_DETACH : 0));
90 }
91 
92 int
93 devctl_suspend(const char *device)
94 {
95 
96 	return (devctl_simple_request(DEV_SUSPEND, device, 0));
97 }
98 
99 int
100 devctl_resume(const char *device)
101 {
102 
103 	return (devctl_simple_request(DEV_RESUME, device, 0));
104 }
105 
106 int
107 devctl_set_driver(const char *device, const char *driver, bool force)
108 {
109 	struct devreq req;
110 
111 	memset(&req, 0, sizeof(req));
112 	if (strlcpy(req.dr_name, device, sizeof(req.dr_name)) >=
113 	    sizeof(req.dr_name)) {
114 		errno = EINVAL;
115 		return (-1);
116 	}
117 	req.dr_data = __DECONST(char *, driver);
118 	if (force)
119 		req.dr_flags |= DEVF_SET_DRIVER_DETACH;
120 	return (devctl_request(DEV_SET_DRIVER, &req));
121 }
122 
123 int
124 devctl_clear_driver(const char *device, bool force)
125 {
126 
127 	return (devctl_simple_request(DEV_CLEAR_DRIVER, device, force ?
128 	    DEVF_CLEAR_DRIVER_DETACH : 0));
129 }
130 
131 int
132 devctl_rescan(const char *device)
133 {
134 
135 	return (devctl_simple_request(DEV_RESCAN, device, 0));
136 }
137 
138 int
139 devctl_delete(const char *device, bool force)
140 {
141 
142 	return (devctl_simple_request(DEV_DELETE, device, force ?
143 	    DEVF_FORCE_DELETE : 0));
144 }
145 
146 int
147 devctl_freeze(void)
148 {
149 
150 	return (devctl_simple_request(DEV_FREEZE, "", 0));
151 }
152 
153 int
154 devctl_thaw(void)
155 {
156 
157 	return (devctl_simple_request(DEV_THAW, "", 0));
158 }
159 
160 int
161 devctl_reset(const char *device, bool detach)
162 {
163 
164 	return (devctl_simple_request(DEV_RESET, device, detach ?
165 	    DEVF_RESET_DETACH : 0));
166 }
167 
168 #define BUFLEN 1024
169 
170 int
171 devctl_getpath(const char *device, const char *locator, char **buffer)
172 {
173 	struct devreq req;
174 	int serrno;
175 
176 	memset(&req, 0, sizeof(req));
177 	if (strlcpy(req.dr_name, device, sizeof(req.dr_name)) >=
178 	    sizeof(req.dr_name)) {
179 		errno = EINVAL;
180 		*buffer = NULL;
181 		return (-1);
182 	}
183 
184 	/*
185 	 * Maybe do the request twice. Once to get the length, and then again to
186 	 * get the string if BUFLEN bytes is insufficient.
187 	 */
188 	req.dr_flags = 0;
189 	req.dr_buffer.length = BUFLEN;
190 again:
191 	req.dr_buffer.buffer = malloc(req.dr_buffer.length);
192 	strlcpy(req.dr_buffer.buffer, locator, req.dr_buffer.length);
193 	if (devctl_request(DEV_GET_PATH, &req) == 0) {
194 		*buffer = req.dr_buffer.buffer;
195 		return (0);
196 	}
197 	if (errno == ENAMETOOLONG && req.dr_buffer.length != BUFLEN) {
198 		free(req.dr_buffer.buffer);
199 		goto again;
200 	}
201 	serrno = errno;
202 	free(req.dr_buffer.buffer);
203 	errno = serrno;
204 	*buffer = NULL;
205 	return (-1);
206 }
207