xref: /freebsd/usr.sbin/trim/trim.c (revision 2e3f49888ec8851bafb22011533217487764fdb0)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2019 Eugene Grosbein <eugen@FreeBSD.org>.
5  * Contains code written by Alan Somers <asomers@FreeBSD.org>.
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 
30 #include <sys/disk.h>
31 #include <sys/ioctl.h>
32 #include <sys/stat.h>
33 
34 #include <err.h>
35 #include <errno.h>
36 #include <fcntl.h>
37 #include <libutil.h>
38 #include <limits.h>
39 #include <paths.h>
40 #include <stdbool.h>
41 #include <stdio.h>
42 #include <stdlib.h>
43 #include <string.h>
44 #include <sysexits.h>
45 #include <unistd.h>
46 
47 #include <sys/cdefs.h>
48 static bool	candelete(int fd);
49 static off_t	getsize(const char *path);
50 static int	opendev(const char *path, int flags);
51 static int	trim(const char *path, off_t offset, off_t length, bool dryrun, bool verbose);
52 static void	usage(const char *name);
53 
54 int
55 main(int argc, char **argv)
56 {
57 	off_t offset, length;
58 	uint64_t usz;
59 	int ch, error;
60 	bool dryrun, verbose;
61 	char *fname, *name;
62 
63 	error = 0;
64 	length = offset = 0;
65 	name = argv[0];
66 	dryrun = verbose = true;
67 
68 	while ((ch = getopt(argc, argv, "Nfl:o:qr:v")) != -1)
69 		switch (ch) {
70 		case 'N':
71 			dryrun = true;
72 			verbose = true;
73 			break;
74 		case 'f':
75 			dryrun = false;
76 			break;
77 		case 'l':
78 		case 'o':
79 			if (expand_number(optarg, &usz) == -1 ||
80 					(off_t)usz < 0 || (usz == 0 && ch == 'l'))
81 				errx(EX_USAGE,
82 					"invalid %s of the region: %s",
83 					ch == 'o' ? "offset" : "length",
84 					optarg);
85 			if (ch == 'o')
86 				offset = (off_t)usz;
87 			else
88 				length = (off_t)usz;
89 			break;
90 		case 'q':
91 			verbose = false;
92 			break;
93 		case 'r':
94 			if ((length = getsize(optarg)) == 0)
95 				errx(EX_USAGE,
96 					"invalid zero length reference file"
97 					" for the region: %s", optarg);
98 			break;
99 		case 'v':
100 			verbose = true;
101 			break;
102 		default:
103 			usage(name);
104 			/* NOTREACHED */
105 		}
106 
107 	/*
108 	 * Safety net: do not allow mistakes like
109 	 *
110 	 *	trim -f /dev/da0 -r rfile
111 	 *
112 	 * This would trim whole device then error on non-existing file -r.
113 	 * Following check prevents this while allowing this form still:
114 	 *
115 	 *	trim -f -- /dev/da0 -r rfile
116 	 */
117 
118 	if (strcmp(argv[optind-1], "--") != 0) {
119 		for (ch = optind; ch < argc; ch++)
120 			if (argv[ch][0] == '-')
121 				usage(name);
122 	}
123 
124 	argv += optind;
125 	argc -= optind;
126 
127 	if (argc < 1)
128 		usage(name);
129 
130 	while ((fname = *argv++) != NULL)
131 		if (trim(fname, offset, length, dryrun, verbose) < 0)
132 			error++;
133 
134 	return (error ? EXIT_FAILURE : EXIT_SUCCESS);
135 }
136 
137 static bool
138 candelete(int fd)
139 {
140 	struct diocgattr_arg arg;
141 
142 	strlcpy(arg.name, "GEOM::candelete", sizeof(arg.name));
143 	arg.len = sizeof(arg.value.i);
144 	if (ioctl(fd, DIOCGATTR, &arg) == 0)
145 		return (arg.value.i != 0);
146 	else
147 		return (false);
148 }
149 
150 static int
151 opendev(const char *path, int flags)
152 {
153 	int fd;
154 	char *tstr;
155 
156 	if ((fd = open(path, flags)) < 0) {
157 		if (errno == ENOENT && path[0] != '/') {
158 			if (asprintf(&tstr, "%s%s", _PATH_DEV, path) < 0)
159 				errx(EX_OSERR, "no memory");
160 			fd = open(tstr, flags);
161 			free(tstr);
162 		}
163 	}
164 
165 	if (fd < 0)
166 		err(EX_NOINPUT, "open failed: %s", path);
167 
168 	return (fd);
169 }
170 
171 static off_t
172 getsize(const char *path)
173 {
174 	struct stat sb;
175 	off_t mediasize;
176 	int fd;
177 
178 	fd = opendev(path, O_RDONLY | O_DIRECT);
179 
180 	if (fstat(fd, &sb) < 0)
181 		err(EX_IOERR, "fstat failed: %s", path);
182 
183 	if (S_ISREG(sb.st_mode) || S_ISDIR(sb.st_mode)) {
184 		close(fd);
185 		return (sb.st_size);
186 	}
187 
188 	if (!S_ISCHR(sb.st_mode) && !S_ISBLK(sb.st_mode))
189 		errx(EX_DATAERR,
190 			"invalid type of the file "
191 			"(not regular, directory nor special device): %s",
192 			path);
193 
194 	if (ioctl(fd, DIOCGMEDIASIZE, &mediasize) < 0)
195 		err(EX_UNAVAILABLE,
196 			"ioctl(DIOCGMEDIASIZE) failed, probably not a disk: "
197 			"%s", path);
198 
199 	close(fd);
200 	return (mediasize);
201 }
202 
203 static int
204 trim(const char *path, off_t offset, off_t length, bool dryrun, bool verbose)
205 {
206 	off_t arg[2];
207 	int error, fd;
208 
209 	if (length == 0)
210 		length = getsize(path);
211 
212 	if (verbose)
213 		printf("trim %s offset %ju length %ju\n",
214 		    path, (uintmax_t)offset, (uintmax_t)length);
215 
216 	if (dryrun) {
217 		printf("dry run: add -f to actually perform the operation\n");
218 		return (0);
219 	}
220 
221 	fd = opendev(path, O_RDWR | O_DIRECT);
222 	arg[0] = offset;
223 	arg[1] = length;
224 
225 	error = ioctl(fd, DIOCGDELETE, arg);
226 	if (error < 0) {
227 		if (errno == EOPNOTSUPP && verbose && !candelete(fd))
228 			warnx("%s: TRIM/UNMAP not supported by driver", path);
229 		else
230 			warn("ioctl(DIOCGDELETE) failed: %s", path);
231 	}
232 	close(fd);
233 	return (error);
234 }
235 
236 static void
237 usage(const char *name)
238 {
239 	(void)fprintf(stderr,
240 	    "usage: %s [-[lo] offset[K|k|M|m|G|g|T|t]] [-r rfile] [-Nfqv] device ...\n",
241 	    name);
242 	exit(EX_USAGE);
243 }
244