Training courses

Kernel and Embedded Linux

Bootlin training courses

Embedded Linux, kernel,
Yocto Project, Buildroot, real-time,
graphics, boot time, debugging...

Bootlin logo

Elixir Cross Referencer

/*	$NetBSD: clri.c,v 1.26 2023/02/26 22:55:02 andvar Exp $	*/

/*
 * Copyright (c) 1990, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Rich $alz of BBN Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/cdefs.h>
#ifndef lint
__COPYRIGHT("@(#) Copyright (c) 1990, 1993\
 The Regents of the University of California.  All rights reserved.");
#endif /* not lint */

#ifndef lint
#if 0
static char sccsid[] = "@(#)clri.c	8.3 (Berkeley) 4/28/95";
#else
__RCSID("$NetBSD: clri.c,v 1.26 2023/02/26 22:55:02 andvar Exp $");
#endif
#endif /* not lint */

#include <sys/param.h>
#include <sys/time.h>

#include <ufs/ufs/dinode.h>
#include <ufs/ufs/ufs_bswap.h>
#include <ufs/ffs/fs.h>
#include <ufs/ffs/ffs_extern.h>

#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>

/*
 * Possible superblock locations ordered from most to least likely.
 */
static off_t sblock_try[] = SBLOCKSEARCH;
off_t sblockloc;


int
main(int argc, char *argv[])
{
	struct fs *sbp;
	struct ufs1_dinode *ip1;
	struct ufs2_dinode *ip2;
	int fd;
	void *ibuf;
	int32_t generation;
	off_t offset;
	size_t bsize;
	int inonum;
	char *fs, sblock[SBLOCKSIZE];
	int needswap = 0, is_ufs2 = 0;
	int i, imax;
	long dev_bsize;

	if (argc < 3) {
		(void)fprintf(stderr, "usage: clri filesystem inode ...\n");
		exit(1);
	}

	fs = *++argv;


	/* get the superblock. */
	if ((fd = open(fs, O_RDWR, 0)) < 0)
		err(1, "%s", fs);
	for (i = 0;; i++) {
		sblockloc = sblock_try[i];
		if (sblockloc == -1)
			errx(1, "%s: can't find superblock", fs);
		if (pread(fd, sblock, sizeof(sblock), sblockloc) != sizeof(sblock))
			errx(1, "%s: can't read superblock", fs);

		sbp = (struct fs *)sblock;
		switch(sbp->fs_magic) {
		case FS_UFS2_MAGIC:
		case FS_UFS2EA_MAGIC:
			is_ufs2 = 1;
			/*FALLTHROUGH*/
		case FS_UFS1_MAGIC:
			break;
		case FS_UFS2_MAGIC_SWAPPED:
		case FS_UFS2EA_MAGIC_SWAPPED:
			is_ufs2 = 1;
			/*FALLTHROUGH*/
		case FS_UFS1_MAGIC_SWAPPED:
			needswap = 1;
			break;
		default:
			continue;
		}

		/* check we haven't found an alternate */
		if (is_ufs2 || sbp->fs_old_flags & FS_FLAGS_UPDATED) {
			if ((uint64_t)sblockloc != ufs_rw64(sbp->fs_sblockloc, needswap))
				continue;
		} else {
			if (sblockloc == SBLOCK_UFS2)
				continue;
		}

		break;
	}

	/* check that inode numbers are valid */
	imax = ufs_rw32(sbp->fs_ncg, needswap) *
		ufs_rw32(sbp->fs_ipg, needswap);
	for (i = 1; i < (argc - 1); i++)
		if (atoi(argv[i]) <= 0 || atoi(argv[i]) >= imax) 
			errx(1, "%s is not a valid inode number", argv[i]);

	/* delete clean flag in the superblock */
	sbp->fs_clean = ufs_rw32(ufs_rw32(sbp->fs_clean, needswap) << 1,
				needswap);
	if (lseek(fd, sblockloc, SEEK_SET) < 0)
		err(1, "%s", fs);
	if (write(fd, sblock, sizeof(sblock)) != sizeof(sblock))
		errx(1, "%s: can't rewrite superblock", fs);
	(void)fsync(fd);

	if (needswap)
		ffs_sb_swap(sbp, sbp);

	/* compute disk block size from superblock parameters */
	dev_bsize = sbp->fs_fsize / FFS_FSBTODB(sbp, 1);

	bsize = sbp->fs_bsize;
	ibuf = malloc(bsize);
	if (ibuf == NULL) {
		err(1, "malloc");
	}

	/* remaining arguments are inode numbers. */
	while (*++argv) {
		/* get the inode number. */
		inonum = atoi(*argv);
		(void)printf("clearing %d\n", inonum);

		/* read in the appropriate block. */
		offset = ino_to_fsba(sbp, inonum);	/* inode to fs blk */
		offset = FFS_FSBTODB(sbp, offset);	/* fs blk disk blk */
		offset *= dev_bsize;			/* disk blk to bytes */

		/* seek and read the block */
		if (lseek(fd, offset, SEEK_SET) < 0)
			err(1, "%s", fs);
		if ((size_t)read(fd, ibuf, bsize) != bsize)
			err(1, "%s", fs);

		/* get the inode within the block. */
		if (is_ufs2) {
			ip2 = &((struct ufs2_dinode *)ibuf)
			    [ino_to_fsbo(sbp, inonum)];
			/* clear the inode, and bump the generation count. */
			generation = ip2->di_gen + 1;
			memset(ip2, 0, sizeof(*ip2));
			ip2->di_gen = generation;
		} else {
			ip1 = &((struct ufs1_dinode *)ibuf)
			    [ino_to_fsbo(sbp, inonum)];
			/* clear the inode, and bump the generation count. */
			generation = ip1->di_gen + 1;
			memset(ip1, 0, sizeof(*ip1));
			ip1->di_gen = generation;
		}

		/* backup and write the block */
		if (lseek(fd, offset, SEEK_SET) < 0)
			err(1, "%s", fs);
		if ((size_t)write(fd, ibuf, bsize) != bsize)
			err(1, "%s", fs);
		(void)fsync(fd);
	}
	free(ibuf);
	(void)close(fd);
	exit(0);
}