usr.sbin/trim/trim.c

   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 }