xref: /freebsd/lib/libdevctl/devctl.c (revision 22cf89c938886d14f5796fc49f9f020c23ea8eaf)
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 #include <sys/types.h>
28 #include <sys/bus.h>
29 #include <errno.h>
30 #include <fcntl.h>
31 #include <stdlib.h>
32 #include <string.h>
33 #include "devctl.h"
34 
35 static int
36 devctl_request(u_long cmd, struct devreq *req)
37 {
38 	static int devctl2_fd = -1;
39 
40 	if (devctl2_fd == -1) {
41 		devctl2_fd = open("/dev/devctl2", O_RDONLY);
42 		if (devctl2_fd == -1)
43 			return (-1);
44 	}
45 	return (ioctl(devctl2_fd, cmd, req));
46 }
47 
48 static int
49 devctl_simple_request(u_long cmd, const char *name, int flags)
50 {
51 	struct devreq req;
52 
53 	memset(&req, 0, sizeof(req));
54 	if (strlcpy(req.dr_name, name, sizeof(req.dr_name)) >=
55 	    sizeof(req.dr_name)) {
56 		errno = EINVAL;
57 		return (-1);
58 	}
59 	req.dr_flags = flags;
60 	return (devctl_request(cmd, &req));
61 }
62 
63 int
64 devctl_attach(const char *device)
65 {
66 
67 	return (devctl_simple_request(DEV_ATTACH, device, 0));
68 }
69 
70 int
71 devctl_detach(const char *device, bool force)
72 {
73 
74 	return (devctl_simple_request(DEV_DETACH, device, force ?
75 	    DEVF_FORCE_DETACH : 0));
76 }
77 
78 int
79 devctl_enable(const char *device)
80 {
81 
82 	return (devctl_simple_request(DEV_ENABLE, device, 0));
83 }
84 
85 int
86 devctl_disable(const char *device, bool force_detach)
87 {
88 
89 	return (devctl_simple_request(DEV_DISABLE, device, force_detach ?
90 	    DEVF_FORCE_DETACH : 0));
91 }
92 
93 int
94 devctl_suspend(const char *device)
95 {
96 
97 	return (devctl_simple_request(DEV_SUSPEND, device, 0));
98 }
99 
100 int
101 devctl_resume(const char *device)
102 {
103 
104 	return (devctl_simple_request(DEV_RESUME, device, 0));
105 }
106 
107 int
108 devctl_set_driver(const char *device, const char *driver, bool force)
109 {
110 	struct devreq req;
111 
112 	memset(&req, 0, sizeof(req));
113 	if (strlcpy(req.dr_name, device, sizeof(req.dr_name)) >=
114 	    sizeof(req.dr_name)) {
115 		errno = EINVAL;
116 		return (-1);
117 	}
118 	req.dr_data = __DECONST(char *, driver);
119 	if (force)
120 		req.dr_flags |= DEVF_SET_DRIVER_DETACH;
121 	return (devctl_request(DEV_SET_DRIVER, &req));
122 }
123 
124 int
125 devctl_clear_driver(const char *device, bool force)
126 {
127 
128 	return (devctl_simple_request(DEV_CLEAR_DRIVER, device, force ?
129 	    DEVF_CLEAR_DRIVER_DETACH : 0));
130 }
131 
132 int
133 devctl_rescan(const char *device)
134 {
135 
136 	return (devctl_simple_request(DEV_RESCAN, device, 0));
137 }
138 
139 int
140 devctl_delete(const char *device, bool force)
141 {
142 
143 	return (devctl_simple_request(DEV_DELETE, device, force ?
144 	    DEVF_FORCE_DELETE : 0));
145 }
146 
147 int
148 devctl_freeze(void)
149 {
150 
151 	return (devctl_simple_request(DEV_FREEZE, "", 0));
152 }
153 
154 int
155 devctl_thaw(void)
156 {
157 
158 	return (devctl_simple_request(DEV_THAW, "", 0));
159 }
160 
161 int
162 devctl_reset(const char *device, bool detach)
163 {
164 
165 	return (devctl_simple_request(DEV_RESET, device, detach ?
166 	    DEVF_RESET_DETACH : 0));
167 }
168 
169 #define BUFLEN 1024
170 
171 int
172 devctl_getpath(const char *device, const char *locator, char **buffer)
173 {
174 	struct devreq req;
175 	int serrno;
176 
177 	memset(&req, 0, sizeof(req));
178 	if (strlcpy(req.dr_name, device, sizeof(req.dr_name)) >=
179 	    sizeof(req.dr_name)) {
180 		errno = EINVAL;
181 		*buffer = NULL;
182 		return (-1);
183 	}
184 
185 	/*
186 	 * Maybe do the request twice. Once to get the length, and then again to
187 	 * get the string if BUFLEN bytes is insufficient.
188 	 */
189 	req.dr_flags = 0;
190 	req.dr_buffer.length = BUFLEN;
191 again:
192 	req.dr_buffer.buffer = malloc(req.dr_buffer.length);
193 	strlcpy(req.dr_buffer.buffer, locator, req.dr_buffer.length);
194 	if (devctl_request(DEV_GET_PATH, &req) == 0) {
195 		*buffer = req.dr_buffer.buffer;
196 		return (0);
197 	}
198 	if (errno == ENAMETOOLONG && req.dr_buffer.length != BUFLEN) {
199 		free(req.dr_buffer.buffer);
200 		goto again;
201 	}
202 	serrno = errno;
203 	free(req.dr_buffer.buffer);
204 	errno = serrno;
205 	*buffer = NULL;
206 	return (-1);
207 }
208