xref: /freebsd/usr.sbin/trim/trim.c (revision 0b57cec536236d46e3dba9bd041533462f33dbb7)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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 __FBSDID("$FreeBSD$");
49 
50 static bool	candelete(int fd);
51 static off_t	getsize(const char *path);
52 static int	opendev(const char *path, int flags);
53 static int	trim(const char *path, off_t offset, off_t length, bool dryrun, bool verbose);
54 static void	usage(const char *name);
55 
56 int
57 main(int argc, char **argv)
58 {
59 	off_t offset, length;
60 	uint64_t usz;
61 	int ch, error;
62 	bool dryrun, verbose;
63 	char *fname, *name;
64 
65 	error = 0;
66 	length = offset = 0;
67 	name = argv[0];
68 	dryrun = verbose = true;
69 
70 	while ((ch = getopt(argc, argv, "Nfl:o:qr:v")) != -1)
71 		switch (ch) {
72 		case 'N':
73 			dryrun = true;
74 			verbose = true;
75 			break;
76 		case 'f':
77 			dryrun = false;
78 			break;
79 		case 'l':
80 		case 'o':
81 			if (expand_number(optarg, &usz) == -1 ||
82 					(off_t)usz < 0 || (usz == 0 && ch == 'l'))
83 				errx(EX_USAGE,
84 					"invalid %s of the region: %s",
85 					ch == 'o' ? "offset" : "length",
86 					optarg);
87 			if (ch == 'o')
88 				offset = (off_t)usz;
89 			else
90 				length = (off_t)usz;
91 			break;
92 		case 'q':
93 			verbose = false;
94 			break;
95 		case 'r':
96 			if ((length = getsize(optarg)) == 0)
97 				errx(EX_USAGE,
98 					"invalid zero length reference file"
99 					" for the region: %s", optarg);
100 			break;
101 		case 'v':
102 			verbose = true;
103 			break;
104 		default:
105 			usage(name);
106 			/* NOTREACHED */
107 		}
108 
109 	/*
110 	 * Safety net: do not allow mistakes like
111 	 *
112 	 *	trim -f /dev/da0 -r rfile
113 	 *
114 	 * This would trim whole device then error on non-existing file -r.
115 	 * Following check prevents this while allowing this form still:
116 	 *
117 	 *	trim -f -- /dev/da0 -r rfile
118 	 */
119 
120 	if (strcmp(argv[optind-1], "--") != 0) {
121 		for (ch = optind; ch < argc; ch++)
122 			if (argv[ch][0] == '-')
123 				usage(name);
124 	}
125 
126 	argv += optind;
127 	argc -= optind;
128 
129 	if (argc < 1)
130 		usage(name);
131 
132 	while ((fname = *argv++) != NULL)
133 		if (trim(fname, offset, length, dryrun, verbose) < 0)
134 			error++;
135 
136 	return (error ? EXIT_FAILURE : EXIT_SUCCESS);
137 }
138 
139 static bool
140 candelete(int fd)
141 {
142 	struct diocgattr_arg arg;
143 
144 	strlcpy(arg.name, "GEOM::candelete", sizeof(arg.name));
145 	arg.len = sizeof(arg.value.i);
146 	if (ioctl(fd, DIOCGATTR, &arg) == 0)
147 		return (arg.value.i != 0);
148 	else
149 		return (false);
150 }
151 
152 static int
153 opendev(const char *path, int flags)
154 {
155 	int fd;
156 	char *tstr;
157 
158 	if ((fd = open(path, flags)) < 0) {
159 		if (errno == ENOENT && path[0] != '/') {
160 			if (asprintf(&tstr, "%s%s", _PATH_DEV, path) < 0)
161 				errx(EX_OSERR, "no memory");
162 			fd = open(tstr, flags);
163 			free(tstr);
164 		}
165 	}
166 
167 	if (fd < 0)
168 		err(EX_NOINPUT, "open failed: %s", path);
169 
170 	return (fd);
171 }
172 
173 static off_t
174 getsize(const char *path)
175 {
176 	struct stat sb;
177 	off_t mediasize;
178 	int fd;
179 
180 	fd = opendev(path, O_RDONLY | O_DIRECT);
181 
182 	if (fstat(fd, &sb) < 0)
183 		err(EX_IOERR, "fstat failed: %s", path);
184 
185 	if (S_ISREG(sb.st_mode) || S_ISDIR(sb.st_mode)) {
186 		close(fd);
187 		return (sb.st_size);
188 	}
189 
190 	if (!S_ISCHR(sb.st_mode) && !S_ISBLK(sb.st_mode))
191 		errx(EX_DATAERR,
192 			"invalid type of the file "
193 			"(not regular, directory nor special device): %s",
194 			path);
195 
196 	if (ioctl(fd, DIOCGMEDIASIZE, &mediasize) < 0)
197 		err(EX_UNAVAILABLE,
198 			"ioctl(DIOCGMEDIASIZE) failed, probably not a disk: "
199 			"%s", path);
200 
201 	close(fd);
202 	return (mediasize);
203 }
204 
205 static int
206 trim(const char *path, off_t offset, off_t length, bool dryrun, bool verbose)
207 {
208 	off_t arg[2];
209 	int error, fd;
210 
211 	if (length == 0)
212 		length = getsize(path);
213 
214 	if (verbose)
215 		printf("trim %s offset %ju length %ju\n",
216 		    path, (uintmax_t)offset, (uintmax_t)length);
217 
218 	if (dryrun) {
219 		printf("dry run: add -f to actually perform the operation\n");
220 		return (0);
221 	}
222 
223 	fd = opendev(path, O_WRONLY | O_DIRECT);
224 	arg[0] = offset;
225 	arg[1] = length;
226 
227 	error = ioctl(fd, DIOCGDELETE, arg);
228 	if (error < 0) {
229 		if (errno == EOPNOTSUPP && verbose && !candelete(fd))
230 			warnx("%s: TRIM/UNMAP not supported by driver", path);
231 		else
232 			warn("ioctl(DIOCGDELETE) failed: %s", path);
233 	}
234 	close(fd);
235 	return (error);
236 }
237 
238 static void
239 usage(const char *name)
240 {
241 	(void)fprintf(stderr,
242 	    "usage: %s [-[lo] offset[K|k|M|m|G|g|T|t]] [-r rfile] [-Nfqv] device ...\n",
243 	    name);
244 	exit(EX_USAGE);
245 }
246