xref: /netbsd-src/sbin/resize_lfs/resize_lfs.c (revision df0caa2637da0538ecdf6b878c4d08e684b43d8f)
1 /*	$NetBSD: resize_lfs.c,v 1.2 2005/06/02 01:16:06 lukem 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  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *      This product includes software developed by the NetBSD
20  *      Foundation, Inc. and its contributors.
21  * 4. Neither the name of The NetBSD Foundation nor the names of its
22  *    contributors may be used to endorse or promote products derived
23  *    from this software without specific prior written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
26  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
29  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35  * POSSIBILITY OF SUCH DAMAGE.
36  */
37 
38 #include <sys/param.h>
39 #include <sys/types.h>
40 #include <sys/stat.h>
41 #include <sys/ioctl.h>
42 #include <sys/disklabel.h>
43 #include <sys/file.h>
44 #include <sys/mount.h>
45 #include <sys/statvfs.h>
46 
47 #include <ufs/ufs/dinode.h>
48 #include <ufs/lfs/lfs.h>
49 
50 #include <disktab.h>
51 #include <err.h>
52 #include <stdio.h>
53 #include <stdlib.h>
54 #include <string.h>
55 #include <unistd.h>
56 
57 static void
58 usage(void)
59 {
60 	errx(1, "usage: resize_lfs [-v] [-s new-size] [filesystem]\n");
61 }
62 
63 int
64 main(int argc, char **argv)
65 {
66 	char *cp, *rdev, *fsname, buf[LFS_SBPAD];
67 	daddr_t newsize, newnsegs;
68 	int devfd, rootfd;
69 	int ch, i, verbose;
70 	off_t secsize, sboff;
71 	struct disklabel lbl;
72 	struct lfs *fs;
73 	struct partition *pp;
74 	struct statvfs vfs;
75 
76 	/* Initialize and parse arguments */
77 	verbose = 0;
78 	newsize = 0;
79 	while ((ch = getopt(argc, argv, "s:v")) != -1) {
80 		switch(ch) {
81 		case 's':	/* New size, in sectors */
82 			newsize = strtoll(optarg, NULL, 10);
83 			break;
84 		case 'v':
85 			++verbose;
86 			break;
87 		default:
88 			usage();
89 		}
90 	}
91 	fsname = argv[optind];
92 
93 	if (fsname == NULL)
94 		usage();
95 
96 	/*
97 	 * If the user did not supply a filesystem size, use the
98 	 * length of the mounted partition.
99 	 */
100 	if (statvfs(fsname, &vfs) < 0)
101 		err(1, "%s", fsname);
102 	rdev = (char *)malloc(strlen(vfs.f_mntfromname + 2));
103 	sprintf(rdev, "/dev/r%s", vfs.f_mntfromname + 5);
104 	devfd = open(rdev, O_RDONLY);
105 	if (devfd < 0)
106 		err(1, "open raw device");
107 
108 	/*
109 	 * Read the disklabel to find the sector size.  Check the
110 	 * given size against the partition size.  We can skip some
111 	 * error checking here since we know the fs is mountable.
112 	 */
113 	if (ioctl(devfd, DIOCGDINFO, &lbl) < 0)
114 		err(1, "%s: ioctl (GDINFO)", rdev);
115 	secsize = lbl.d_secsize;
116 	cp = strchr(rdev, '\0') - 1;
117 	pp = &lbl.d_partitions[*cp - 'a'];
118 	if (newsize > pp->p_size)
119 		errx(1, "new size must be <= the partition size");
120 	if (newsize == 0)
121 		newsize = pp->p_size;
122 
123 	/* Open the root of the filesystem so we can fcntl() it */
124 	rootfd = open(fsname, O_RDONLY);
125 	if (rootfd < 0)
126 		err(1, "open filesystem root");
127 
128 	/* Read the superblock, finding alternates if necessary */
129 	fs = (struct lfs *)malloc(sizeof(*fs));
130 	for (sboff = LFS_LABELPAD;;) {
131 		pread(devfd, buf, sboff, LFS_SBPAD);
132 		memcpy(&fs->lfs_dlfs, buf, sizeof(struct dlfs));
133 		if (sboff == LFS_LABELPAD && fsbtob(fs, 1) > LFS_LABELPAD)
134 			sboff = fsbtob(fs, (off_t)fs->lfs_sboffs[0]);
135 		else
136 			break;
137 	}
138 	close(devfd);
139 
140 	/* Calculate new number of segments. */
141 	newnsegs = (newsize * secsize) / fs->lfs_ssize;
142 	if (newnsegs == fs->lfs_nseg) {
143 		errx(0, "the filesystem is unchanged.");
144 	}
145 
146 	/*
147 	 * If the new filesystem is smaller than the old, we have to
148 	 * invalidate the segments that extend beyond the new boundary.
149 	 * Make the cleaner do this for us.
150 	 * (XXX make the kernel able to do this instead?)
151 	 */
152 	for (i = fs->lfs_nseg - 1; i >= newnsegs; --i) {
153 		char cmd[80];
154 
155 		/* If it's already empty, don't call the cleaner */
156 		if (fcntl(rootfd, LFCNINVAL, &i) == 0)
157 			continue;
158 
159 		sprintf(cmd, "/usr/libexec/lfs_cleanerd -q -i %d %s", i, fsname);
160 		if (system(cmd) != 0)
161 			err(1, "invalidating segment %d", i);
162 	}
163 
164 	/* Tell the filesystem to resize itself. */
165 	if (fcntl(rootfd, LFCNRESIZE, &newnsegs) == -1) {
166 		err(1, "resizing");
167 	}
168 
169 	if (verbose)
170 		printf("Successfully resized %s from %d to %lld segments\n",
171 			fsname, fs->lfs_nseg, (long long)newnsegs);
172 	return 0;
173 }
174