1/*	$NetBSD: resize_lfs.c,v 1.16 2023/08/07 23:27:07 mrg 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/lfs/lfs.h>
42#include <ufs/lfs/lfs_accessors.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#include <util.h>
51
52#include "partutil.h"
53
54static void
55usage(void)
56{
57	errx(1, "usage: resize_lfs [-v] [-s new-size] [filesystem]");
58}
59
60int
61main(int argc, char **argv)
62{
63	char *rdev, *fsname, buf[LFS_SBPAD];
64	size_t rdevlen;
65	daddr_t newsize, newnsegs;
66	int devfd, rootfd;
67	int ch, i, verbose;
68	off_t secsize, sboff;
69	struct disk_geom geo;
70	struct dkwedge_info dkw;
71	struct lfs *fs;
72	struct statvfs vfs;
73
74	/* Initialize and parse arguments */
75	verbose = 0;
76	newsize = 0;
77	while ((ch = getopt(argc, argv, "s:v")) != -1) {
78		switch(ch) {
79		case 's':	/* New size, in sectors */
80			newsize = strtoll(optarg, NULL, 10);
81			break;
82		case 'v':
83			++verbose;
84			break;
85		default:
86			usage();
87		}
88	}
89	fsname = argv[optind];
90
91	if (fsname == NULL)
92		usage();
93
94	/*
95	 * If the user did not supply a filesystem size, use the
96	 * length of the mounted partition.
97	 */
98	if (statvfs(fsname, &vfs) < 0)
99		err(1, "%s", fsname);
100	rdevlen = strlen(vfs.f_mntfromname) + 2;
101	rdev = malloc(rdevlen);
102	if (getdiskrawname(rdev, rdevlen, vfs.f_mntfromname) == NULL)
103		err(1, "Could not convert '%s' to raw name", vfs.f_mntfromname);
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 (getdiskinfo(rdev, devfd, NULL, &geo, &dkw) == -1)
114		err(1, "%s: could not get info", rdev);
115	secsize = geo.dg_secsize;
116	if (newsize > dkw.dkw_size)
117		errx(1, "new size must be <= the partition size");
118	if (newsize == 0)
119		newsize = dkw.dkw_size;
120
121	/* Open the root of the filesystem so we can fcntl() it */
122	rootfd = open(fsname, O_RDONLY);
123	if (rootfd < 0)
124		err(1, "open filesystem root");
125
126	/* Read the superblock, finding alternates if necessary */
127	fs = (struct lfs *)calloc(sizeof(*fs), 1);
128	for (sboff = LFS_LABELPAD;;) {
129		pread(devfd, buf, sboff, LFS_SBPAD);
130		__CTASSERT(sizeof(struct dlfs) == sizeof(struct dlfs64));
131		memcpy(&fs->lfs_dlfs_u, buf, sizeof(struct dlfs));
132		if (sboff == LFS_LABELPAD && lfs_fsbtob(fs, 1) > LFS_LABELPAD)
133			sboff = lfs_fsbtob(fs, (off_t)lfs_sb_getsboff(fs, 0));
134		else
135			break;
136	}
137	close(devfd);
138
139	/* Calculate new number of segments. */
140	newnsegs = (newsize * secsize) / lfs_sb_getssize(fs);
141	if (newnsegs == lfs_sb_getnseg(fs)) {
142		errx(0, "the filesystem is unchanged.");
143	}
144
145	/*
146	 * If the new filesystem is smaller than the old, we have to
147	 * invalidate the segments that extend beyond the new boundary.
148	 * Make the cleaner do this for us.
149	 * (XXX make the kernel able to do this instead?)
150	 */
151	for (i = lfs_sb_getnseg(fs) - 1; i >= newnsegs; --i) {
152		char cmd[128];
153
154		/* If it's already empty, don't call the cleaner */
155		if (fcntl(rootfd, LFCNINVAL, &i) == 0)
156			continue;
157
158		snprintf(cmd, sizeof(cmd), "/libexec/lfs_cleanerd -q -i %d %s",
159			 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 %u to %lld segments\n",
171			fsname, lfs_sb_getnseg(fs), (long long)newnsegs);
172	return 0;
173}
174