xref: /freebsd/lib/libgeom/geom_util.c (revision 38c63bdc46252d4d8cd313dff4183ec4546d26d9)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2007 Pawel Jakub Dawidek <pjd@FreeBSD.org>
5  * 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 AUTHORS 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 AUTHORS 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/param.h>
30 #include <sys/disk.h>
31 #include <sys/stat.h>
32 
33 #include <stdio.h>
34 #include <fcntl.h>
35 #include <errno.h>
36 #include <stdint.h>
37 #include <unistd.h>
38 #include <string.h>
39 #include <stdlib.h>
40 #include <paths.h>
41 
42 #include <libgeom.h>
43 
44 static char	*g_device_path_open(const char *, int *, int);
45 
46 /*
47  * Open the given provider and at least check if this is a block device.
48  */
49 int
50 g_open(const char *name, int dowrite)
51 {
52 	char *path;
53 	int fd;
54 
55 	path = g_device_path_open(name, &fd, dowrite);
56 	if (path != NULL)
57 		free(path);
58 	return (fd);
59 }
60 
61 int
62 g_close(int fd)
63 {
64 
65 	return (close(fd));
66 }
67 
68 static int
69 g_ioctl_arg(int fd, unsigned long cmd, void *arg)
70 {
71 	int ret;
72 
73 	if (arg != NULL)
74 		ret = ioctl(fd, cmd, arg);
75 	else
76 		ret = ioctl(fd, cmd);
77 	return (ret >= 0 ? 0 : -1);
78 }
79 
80 static int
81 g_ioctl(int fd, unsigned long cmd)
82 {
83 
84 	return (g_ioctl_arg(fd, cmd, NULL));
85 }
86 
87 /*
88  * Return media size of the given provider.
89  */
90 off_t
91 g_mediasize(int fd)
92 {
93 	off_t mediasize;
94 
95 	if (g_ioctl_arg(fd, DIOCGMEDIASIZE, &mediasize) == -1)
96 		mediasize = -1;
97 	return (mediasize);
98 }
99 
100 /*
101  * Return sector size of the given provider.
102  */
103 ssize_t
104 g_sectorsize(int fd)
105 {
106 	u_int sectorsize;
107 
108 	if (g_ioctl_arg(fd, DIOCGSECTORSIZE, &sectorsize) == -1)
109 		return (-1);
110 	return ((ssize_t)sectorsize);
111 }
112 
113 /*
114  * Return stripe size of the given provider.
115  */
116 off_t
117 g_stripesize(int fd)
118 {
119 	off_t stripesize;
120 
121 	if (g_ioctl_arg(fd, DIOCGSTRIPESIZE, &stripesize) == -1)
122 		return (-1);
123 	return (stripesize);
124 }
125 
126 /*
127  * Return stripe size of the given provider.
128  */
129 off_t
130 g_stripeoffset(int fd)
131 {
132 	off_t stripeoffset;
133 
134 	if (g_ioctl_arg(fd, DIOCGSTRIPEOFFSET, &stripeoffset) == -1)
135 		return (-1);
136 	return (stripeoffset);
137 }
138 
139 /*
140  * Return the correct provider name.
141  */
142 char *
143 g_providername(int fd)
144 {
145 	char name[MAXPATHLEN];
146 
147 	if (g_ioctl_arg(fd, DIOCGPROVIDERNAME, name) == -1)
148 		return (NULL);
149 	return (strdup(name));
150 }
151 
152 /*
153  * Call BIO_FLUSH for the given provider.
154  */
155 int
156 g_flush(int fd)
157 {
158 
159 	return (g_ioctl(fd, DIOCGFLUSH));
160 }
161 
162 /*
163  * Call BIO_DELETE for the given range.
164  */
165 int
166 g_delete(int fd, off_t offset, off_t length)
167 {
168 	off_t arg[2];
169 
170 	arg[0] = offset;
171 	arg[1] = length;
172 	return (g_ioctl_arg(fd, DIOCGDELETE, arg));
173 }
174 
175 /*
176  * Return ID of the given provider.
177  */
178 int
179 g_get_ident(int fd, char *ident, size_t size)
180 {
181 	char lident[DISK_IDENT_SIZE];
182 
183 	if (g_ioctl_arg(fd, DIOCGIDENT, lident) == -1)
184 		return (-1);
185 	if (lident[0] == '\0') {
186 		errno = ENOENT;
187 		return (-1);
188 	}
189 	if (strlcpy(ident, lident, size) >= size) {
190 		errno = ENAMETOOLONG;
191 		return (-1);
192 	}
193 	return (0);
194 }
195 
196 /*
197  * Return name of the provider, which has the given ID.
198  */
199 int
200 g_get_name(const char *ident, char *name, size_t size)
201 {
202 	int fd;
203 
204 	fd = g_open_by_ident(ident, 0, name, size);
205 	if (fd == -1)
206 		return (-1);
207 	g_close(fd);
208 	return (0);
209 }
210 
211 /*
212  * Find provider name by the given ID.
213  */
214 int
215 g_open_by_ident(const char *ident, int dowrite, char *name, size_t size)
216 {
217 	char lident[DISK_IDENT_SIZE];
218 	struct gmesh mesh;
219 	struct gclass *mp;
220 	struct ggeom *gp;
221 	struct gprovider *pp;
222 	int error, fd;
223 
224 	error = geom_gettree(&mesh);
225 	if (error != 0) {
226 		errno = error;
227 		return (-1);
228 	}
229 
230 	error = ENOENT;
231 	fd = -1;
232 
233 	LIST_FOREACH(mp, &mesh.lg_class, lg_class) {
234 		LIST_FOREACH(gp, &mp->lg_geom, lg_geom) {
235 			LIST_FOREACH(pp, &gp->lg_provider, lg_provider) {
236 				fd = g_open(pp->lg_name, dowrite);
237 				if (fd == -1)
238 					continue;
239 				if (g_get_ident(fd, lident,
240 				    sizeof(lident)) == -1) {
241 					g_close(fd);
242 					continue;
243 				}
244 				if (strcmp(ident, lident) != 0) {
245 					g_close(fd);
246 					continue;
247 				}
248 				error = 0;
249 				if (name != NULL && strlcpy(name, pp->lg_name,
250 				    size) >= size) {
251 					error = ENAMETOOLONG;
252 					g_close(fd);
253 				}
254 				goto end;
255 			}
256 		}
257 	}
258 end:
259 	geom_deletetree(&mesh);
260 	if (error != 0) {
261 		errno = error;
262 		return (-1);
263 	}
264 	return (fd);
265 }
266 
267 /*
268  * Return the device path device given a partial or full path to its node.
269  * A pointer can be provided, which will be set to an opened file descriptor of
270  * not NULL.
271  */
272 static char *
273 g_device_path_open(const char *devpath, int *fdp, int dowrite)
274 {
275 	char *path;
276 	int fd;
277 
278 	/* Make sure that we can fail. */
279 	if (fdp != NULL)
280 		*fdp = -1;
281 
282 	/* Use the device node if we're able to open it. */
283 	fd = open(devpath, dowrite ? O_RDWR : O_RDONLY);
284 	if (fd != -1) {
285 		if ((path = strdup(devpath)) == NULL) {
286 			close(fd);
287 			return (NULL);
288 		}
289 		goto fd_ok;
290 	}
291 
292 	/* If we're not given an absolute path, assume /dev/ prefix. */
293 	if (*devpath == '/')
294 		return (NULL);
295 
296 	asprintf(&path, "%s%s", _PATH_DEV, devpath);
297 	if (path == NULL)
298 		return (NULL);
299 	fd = open(path, dowrite ? O_RDWR : O_RDONLY);
300 	if (fd == -1) {
301 		free(path);
302 		return (NULL);
303 	}
304 
305 fd_ok:
306 	/*
307 	 * Let try to get sectorsize, which will prove it is a GEOM provider.
308 	 */
309 	if (g_sectorsize(fd) == -1) {
310 		free(path);
311 		close(fd);
312 		errno = EFTYPE;
313 		return (NULL);
314 	}
315 	if (fdp != NULL)
316 		*fdp = fd;
317 	else
318 		close(fd);
319 	return (path);
320 }
321 
322 char *
323 g_device_path(const char *devpath)
324 {
325 	return (g_device_path_open(devpath, NULL, 0));
326 }
327