sbin/resize_lfs/resize_lfs.c

   1 /*      $NetBSD: resize_lfs.c,v 1.5 2006/11/11 14:47:28 jmmv Exp $      */
   2 /*-
   3  * Copyright (c) 2005 The NetBSD Foundation, Inc.
   4  * All rights reserved.
   5  *
   6  * This code is derived from software contributed to The NetBSD Foundation
   7  * by Konrad E. Schroder <perseant@hhhh.org>.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  19  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  20  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  21  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  22  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  28  * POSSIBILITY OF SUCH DAMAGE.
  29  */
  30
  31 #include <sys/param.h>
  32 #include <sys/types.h>
  33 #include <sys/stat.h>
  34 #include <sys/ioctl.h>
  35 #include <sys/disklabel.h>
  36 #include <sys/disk.h>
  37 #include <sys/file.h>
  38 #include <sys/mount.h>
  39 #include <sys/statvfs.h>
  40
  41 #include <ufs/ufs/dinode.h>
  42 #include <ufs/lfs/lfs.h>
  43
  44 #include <disktab.h>
  45 #include <err.h>
  46 #include <stdio.h>
  47 #include <stdlib.h>
  48 #include <string.h>
  49 #include <unistd.h>
  50
  51 #include "partutil.h"
  52
  53 static void
  54 usage(void)
  55 {
  56         errx(1, "usage: resize_lfs [-v] [-s new-size] [filesystem]");
  57 }
  58
  59 int
  60 main(int argc, char **argv)
  61 {
  62         char *rdev, *fsname, buf[LFS_SBPAD];
  63         daddr_t newsize, newnsegs;
  64         int devfd, rootfd;
  65         int ch, i, verbose;
  66         off_t secsize, sboff;
  67         struct disk_geom geo;
  68         struct dkwedge_info dkw;
  69         struct lfs *fs;
  70         struct statvfs vfs;
  71
  72         /* Initialize and parse arguments */
  73         verbose = 0;
  74         newsize = 0;
  75         while ((ch = getopt(argc, argv, "s:v")) != -1) {
  76                 switch(ch) {
  77                 case 's':       /* New size, in sectors */
  78                         newsize = strtoll(optarg, NULL, 10);
  79                         break;
  80                 case 'v':
  81                         ++verbose;
  82                         break;
  83                 default:
  84                         usage();
  85                 }
  86         }
  87         fsname = argv[optind];
  88
  89         if (fsname == NULL)
  90                 usage();
  91
  92         /*
  93          * If the user did not supply a filesystem size, use the
  94          * length of the mounted partition.
  95          */
  96         if (statvfs(fsname, &vfs) < 0)
  97                 err(1, "%s", fsname);
  98         rdev = (char *)malloc(strlen(vfs.f_mntfromname + 2));
  99         sprintf(rdev, "/dev/r%s", vfs.f_mntfromname + 5);
 100         devfd = open(rdev, O_RDONLY);
 101         if (devfd < 0)
 102                 err(1, "open raw device");
 103
 104         /*
 105          * Read the disklabel to find the sector size.  Check the
 106          * given size against the partition size.  We can skip some
 107          * error checking here since we know the fs is mountable.
 108          */
 109         if (getdiskinfo(rdev, devfd, NULL, &geo, &dkw) == -1)
 110                 err(1, "%s: could not get info", rdev);
 111         secsize = geo.dg_secsize;
 112         if (newsize > dkw.dkw_size)
 113                 errx(1, "new size must be <= the partition size");
 114         if (newsize == 0)
 115                 newsize = dkw.dkw_size;
 116
 117         /* Open the root of the filesystem so we can fcntl() it */
 118         rootfd = open(fsname, O_RDONLY);
 119         if (rootfd < 0)
 120                 err(1, "open filesystem root");
 121
 122         /* Read the superblock, finding alternates if necessary */
 123         fs = (struct lfs *)malloc(sizeof(*fs));
 124         for (sboff = LFS_LABELPAD;;) {
 125                 pread(devfd, buf, sboff, LFS_SBPAD);
 126                 memcpy(&fs->lfs_dlfs, buf, sizeof(struct dlfs));
 127                 if (sboff == LFS_LABELPAD && fsbtob(fs, 1) > LFS_LABELPAD)
 128                         sboff = fsbtob(fs, (off_t)fs->lfs_sboffs[0]);
 129                 else
 130                         break;
 131         }
 132         close(devfd);
 133
 134         /* Calculate new number of segments. */
 135         newnsegs = (newsize * secsize) / fs->lfs_ssize;
 136         if (newnsegs == fs->lfs_nseg) {
 137                 errx(0, "the filesystem is unchanged.");
 138         }
 139
 140         /*
 141          * If the new filesystem is smaller than the old, we have to
 142          * invalidate the segments that extend beyond the new boundary.
 143          * Make the cleaner do this for us.
 144          * (XXX make the kernel able to do this instead?)
 145          */
 146         for (i = fs->lfs_nseg - 1; i >= newnsegs; --i) {
 147                 char cmd[80];
 148
 149                 /* If it's already empty, don't call the cleaner */
 150                 if (fcntl(rootfd, LFCNINVAL, &i) == 0)
 151                         continue;
 152
 153                 sprintf(cmd, "/libexec/lfs_cleanerd -q -i %d %s", i, fsname);
 154                 if (system(cmd) != 0)
 155                         err(1, "invalidating segment %d", i);
 156         }
 157
 158         /* Tell the filesystem to resize itself. */
 159         if (fcntl(rootfd, LFCNRESIZE, &newnsegs) == -1) {
 160                 err(1, "resizing");
 161         }
 162
 163         if (verbose)
 164                 printf("Successfully resized %s from %d to %lld segments\n",
 165                         fsname, fs->lfs_nseg, (long long)newnsegs);
 166         return 0;
 167 }