freebsd-dev/sbin/fsck_ffs/setup.c
Kirk McKusick ac4b20a0a7 After a crash, a file that extends into indirect blocks may end up
shorter than its size resulting in a hole as its final block (which
is a violation of the invarients of the UFS filesystem).

Soft updates will always ensure that the file size is correct when
writing inodes to disk for files that contain only direct block
pointers. However soft updates does not roll back sizes for files
with indirect blocks that it has set to unallocated because their
contents have not yet been written to disk. Hence, the file can
appear to have a hole at its end because the block pointer has been
rolled back to zero when its inode was written to disk. Thus,
fsck_ffs calculates the last allocated block in the file. For files
that extend into indirect blocks, fsck_ffs checks for a size past
the last allocated block of the file and if that is found, shortens
the file to reference the last allocated block thus avoiding having
it reference a hole at its end.

Submitted by: Chuck Silvers <chs@netflix.com>
Tested by:    Chuck Silvers <chs@netflix.com>
MFC after:    1 week
Sponsored by: Netflix
2019-02-25 21:58:19 +00:00

558 lines
16 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1980, 1986, 1993
* The Regents of the University of California. All rights reserved.
*
* 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.
*/
#if 0
#ifndef lint
static const char sccsid[] = "@(#)setup.c 8.10 (Berkeley) 5/9/95";
#endif /* not lint */
#endif
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/disk.h>
#include <sys/stat.h>
#define FSTYPENAMES
#include <sys/disklabel.h>
#include <sys/file.h>
#include <sys/sysctl.h>
#include <ufs/ufs/dinode.h>
#include <ufs/ffs/fs.h>
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <limits.h>
#include <stdint.h>
#include <string.h>
#include <libufs.h>
#include "fsck.h"
struct uufsd disk;
struct bufarea asblk;
#define altsblock (*asblk.b_un.b_fs)
#define POWEROF2(num) (((num) & ((num) - 1)) == 0)
static int calcsb(char *dev, int devfd, struct fs *fs);
static void saverecovery(int readfd, int writefd);
static int chkrecovery(int devfd);
/*
* Read in a superblock finding an alternate if necessary.
* Return 1 if successful, 0 if unsuccessful, -1 if file system
* is already clean (ckclean and preen mode only).
*/
int
setup(char *dev)
{
long cg, asked, i, j;
long bmapsize;
struct stat statb;
struct fs proto;
size_t size;
havesb = 0;
fswritefd = -1;
cursnapshot = 0;
if (stat(dev, &statb) < 0) {
printf("Can't stat %s: %s\n", dev, strerror(errno));
if (bkgrdflag) {
unlink(snapname);
bkgrdflag = 0;
}
return (0);
}
if ((statb.st_mode & S_IFMT) != S_IFCHR &&
(statb.st_mode & S_IFMT) != S_IFBLK) {
if (bkgrdflag != 0 && (statb.st_flags & SF_SNAPSHOT) == 0) {
unlink(snapname);
printf("background fsck lacks a snapshot\n");
exit(EEXIT);
}
if ((statb.st_flags & SF_SNAPSHOT) != 0 && cvtlevel == 0) {
cursnapshot = statb.st_ino;
} else {
if (cvtlevel == 0 ||
(statb.st_flags & SF_SNAPSHOT) == 0) {
if (preen && bkgrdflag) {
unlink(snapname);
bkgrdflag = 0;
}
pfatal("%s is not a disk device", dev);
if (reply("CONTINUE") == 0) {
if (bkgrdflag) {
unlink(snapname);
bkgrdflag = 0;
}
return (0);
}
} else {
if (bkgrdflag) {
unlink(snapname);
bkgrdflag = 0;
}
pfatal("cannot convert a snapshot");
exit(EEXIT);
}
}
}
if ((fsreadfd = open(dev, O_RDONLY)) < 0 ||
ufs_disk_fillout_blank(&disk, dev) < 0) {
if (bkgrdflag) {
unlink(snapname);
bkgrdflag = 0;
}
printf("Can't open %s: %s\n", dev, strerror(errno));
return (0);
}
if (bkgrdflag) {
unlink(snapname);
size = MIBSIZE;
if (sysctlnametomib("vfs.ffs.adjrefcnt", adjrefcnt, &size) < 0||
sysctlnametomib("vfs.ffs.adjblkcnt", adjblkcnt, &size) < 0||
sysctlnametomib("vfs.ffs.setsize", setsize, &size) < 0 ||
sysctlnametomib("vfs.ffs.freefiles", freefiles, &size) < 0||
sysctlnametomib("vfs.ffs.freedirs", freedirs, &size) < 0 ||
sysctlnametomib("vfs.ffs.freeblks", freeblks, &size) < 0) {
pfatal("kernel lacks background fsck support\n");
exit(EEXIT);
}
/*
* When kernel is lack of runtime bgfsck superblock summary
* adjustment functionality, it does not mean we can not
* continue, as old kernels will recompute the summary at
* mount time. However, it will be an unexpected softupdates
* inconsistency if it turns out that the summary is still
* incorrect. Set a flag so subsequent operation can know
* this.
*/
bkgrdsumadj = 1;
if (sysctlnametomib("vfs.ffs.adjndir", adjndir, &size) < 0 ||
sysctlnametomib("vfs.ffs.adjnbfree", adjnbfree, &size) < 0 ||
sysctlnametomib("vfs.ffs.adjnifree", adjnifree, &size) < 0 ||
sysctlnametomib("vfs.ffs.adjnffree", adjnffree, &size) < 0 ||
sysctlnametomib("vfs.ffs.adjnumclusters", adjnumclusters, &size) < 0) {
bkgrdsumadj = 0;
pwarn("kernel lacks runtime superblock summary adjustment support");
}
cmd.version = FFS_CMD_VERSION;
cmd.handle = fsreadfd;
fswritefd = -1;
}
if (preen == 0)
printf("** %s", dev);
if (bkgrdflag == 0 &&
(nflag || ufs_disk_write(&disk) < 0 ||
(fswritefd = dup(disk.d_fd)) < 0)) {
fswritefd = -1;
if (preen)
pfatal("NO WRITE ACCESS");
printf(" (NO WRITE)");
}
if (preen == 0)
printf("\n");
/*
* Read in the superblock, looking for alternates if necessary
*/
if (readsb(1) == 0) {
skipclean = 0;
if (bflag || preen || calcsb(dev, fsreadfd, &proto) == 0)
return(0);
if (reply("LOOK FOR ALTERNATE SUPERBLOCKS") == 0)
return (0);
for (cg = 0; cg < proto.fs_ncg; cg++) {
bflag = fsbtodb(&proto, cgsblock(&proto, cg));
if (readsb(0) != 0)
break;
}
if (cg >= proto.fs_ncg) {
printf("%s %s\n%s %s\n%s %s\n",
"SEARCH FOR ALTERNATE SUPER-BLOCK",
"FAILED. YOU MUST USE THE",
"-b OPTION TO FSCK TO SPECIFY THE",
"LOCATION OF AN ALTERNATE",
"SUPER-BLOCK TO SUPPLY NEEDED",
"INFORMATION; SEE fsck_ffs(8).");
bflag = 0;
return(0);
}
pwarn("USING ALTERNATE SUPERBLOCK AT %jd\n", bflag);
bflag = 0;
}
/* Save copy of things needed by libufs */
memcpy(&disk.d_fs, &sblock, sblock.fs_sbsize);
disk.d_ufs = (sblock.fs_magic == FS_UFS1_MAGIC) ? 1 : 2;
disk.d_bsize = sblock.fs_fsize / fsbtodb(&sblock, 1);
disk.d_sblock = sblock.fs_sblockloc / disk.d_bsize;
disk.d_sbcsum = sblock.fs_csp;
if (skipclean && ckclean && sblock.fs_clean) {
pwarn("FILE SYSTEM CLEAN; SKIPPING CHECKS\n");
return (-1);
}
maxfsblock = sblock.fs_size;
maxino = sblock.fs_ncg * sblock.fs_ipg;
/*
* Check and potentially fix certain fields in the super block.
*/
if (sblock.fs_optim != FS_OPTTIME && sblock.fs_optim != FS_OPTSPACE) {
pfatal("UNDEFINED OPTIMIZATION IN SUPERBLOCK");
if (reply("SET TO DEFAULT") == 1) {
sblock.fs_optim = FS_OPTTIME;
sbdirty();
}
}
if ((sblock.fs_minfree < 0 || sblock.fs_minfree > 99)) {
pfatal("IMPOSSIBLE MINFREE=%d IN SUPERBLOCK",
sblock.fs_minfree);
if (reply("SET TO DEFAULT") == 1) {
sblock.fs_minfree = 10;
sbdirty();
}
}
if (sblock.fs_magic == FS_UFS1_MAGIC &&
sblock.fs_old_inodefmt < FS_44INODEFMT) {
pwarn("Format of file system is too old.\n");
pwarn("Must update to modern format using a version of fsck\n");
pfatal("from before 2002 with the command ``fsck -c 2''\n");
exit(EEXIT);
}
if (asblk.b_dirty && !bflag) {
memmove(&altsblock, &sblock, (size_t)sblock.fs_sbsize);
flush(fswritefd, &asblk);
}
if (preen == 0 && yflag == 0 && sblock.fs_magic == FS_UFS2_MAGIC &&
fswritefd != -1 && chkrecovery(fsreadfd) == 0 &&
reply("SAVE DATA TO FIND ALTERNATE SUPERBLOCKS") != 0)
saverecovery(fsreadfd, fswritefd);
/*
* read in the summary info.
*/
asked = 0;
sblock.fs_csp = Calloc(1, sblock.fs_cssize);
if (sblock.fs_csp == NULL) {
printf("cannot alloc %u bytes for cg summary info\n",
(unsigned)sblock.fs_cssize);
goto badsb;
}
for (i = 0, j = 0; i < sblock.fs_cssize; i += sblock.fs_bsize, j++) {
size = MIN(sblock.fs_cssize - i, sblock.fs_bsize);
readcnt[sblk.b_type]++;
if (blread(fsreadfd, (char *)sblock.fs_csp + i,
fsbtodb(&sblock, sblock.fs_csaddr + j * sblock.fs_frag),
size) != 0 && !asked) {
pfatal("BAD SUMMARY INFORMATION");
if (reply("CONTINUE") == 0) {
ckfini(0);
exit(EEXIT);
}
asked++;
}
}
/*
* allocate and initialize the necessary maps
*/
bmapsize = roundup(howmany(maxfsblock, CHAR_BIT), sizeof(short));
blockmap = Calloc((unsigned)bmapsize, sizeof (char));
if (blockmap == NULL) {
printf("cannot alloc %u bytes for blockmap\n",
(unsigned)bmapsize);
goto badsb;
}
inostathead = Calloc(sblock.fs_ncg, sizeof(struct inostatlist));
if (inostathead == NULL) {
printf("cannot alloc %u bytes for inostathead\n",
(unsigned)(sizeof(struct inostatlist) * (sblock.fs_ncg)));
goto badsb;
}
numdirs = MAX(sblock.fs_cstotal.cs_ndir, 128);
dirhash = numdirs;
inplast = 0;
listmax = numdirs + 10;
inpsort = (struct inoinfo **)Calloc(listmax, sizeof(struct inoinfo *));
inphead = (struct inoinfo **)Calloc(numdirs, sizeof(struct inoinfo *));
if (inpsort == NULL || inphead == NULL) {
printf("cannot alloc %ju bytes for inphead\n",
(uintmax_t)numdirs * sizeof(struct inoinfo *));
goto badsb;
}
bufinit();
if (sblock.fs_flags & FS_DOSOFTDEP)
usedsoftdep = 1;
else
usedsoftdep = 0;
return (1);
badsb:
ckfini(0);
return (0);
}
/*
* Read in the super block and its summary info.
*/
int
readsb(int listerr)
{
off_t super;
int bad, ret;
struct fs *fs;
super = bflag ? bflag * dev_bsize : STDSB;
readcnt[sblk.b_type]++;
if ((ret = sbget(fsreadfd, &fs, super)) != 0) {
switch (ret) {
case EINVAL:
/* Superblock check-hash failed */
return (0);
case ENOENT:
if (bflag)
fprintf(stderr, "%jd is not a file system "
"superblock\n", super / dev_bsize);
else
fprintf(stderr, "Cannot find file system "
"superblock\n");
return (0);
case EIO:
default:
fprintf(stderr, "I/O error reading %jd\n",
super / dev_bsize);
return (0);
}
}
memcpy(&sblock, fs, fs->fs_sbsize);
free(fs);
/*
* Compute block size that the file system is based on,
* according to fsbtodb, and adjust superblock block number
* so we can tell if this is an alternate later.
*/
dev_bsize = sblock.fs_fsize / fsbtodb(&sblock, 1);
sblk.b_bno = sblock.fs_sblockactualloc / dev_bsize;
sblk.b_size = SBLOCKSIZE;
/*
* Compare all fields that should not differ in alternate super block.
* When an alternate super-block is specified this check is skipped.
*/
if (bflag)
goto out;
getblk(&asblk, cgsblock(&sblock, sblock.fs_ncg - 1), sblock.fs_sbsize);
if (asblk.b_errs)
return (0);
bad = 0;
#define CHK(x, y) \
if (altsblock.x != sblock.x) { \
bad++; \
if (listerr && debug) \
printf("SUPER BLOCK VS ALTERNATE MISMATCH %s: " y " vs " y "\n", \
#x, (intmax_t)sblock.x, (intmax_t)altsblock.x); \
}
CHK(fs_sblkno, "%jd");
CHK(fs_cblkno, "%jd");
CHK(fs_iblkno, "%jd");
CHK(fs_dblkno, "%jd");
CHK(fs_ncg, "%jd");
CHK(fs_bsize, "%jd");
CHK(fs_fsize, "%jd");
CHK(fs_frag, "%jd");
CHK(fs_bmask, "%#jx");
CHK(fs_fmask, "%#jx");
CHK(fs_bshift, "%jd");
CHK(fs_fshift, "%jd");
CHK(fs_fragshift, "%jd");
CHK(fs_fsbtodb, "%jd");
CHK(fs_sbsize, "%jd");
CHK(fs_nindir, "%jd");
CHK(fs_inopb, "%jd");
CHK(fs_cssize, "%jd");
CHK(fs_ipg, "%jd");
CHK(fs_fpg, "%jd");
CHK(fs_magic, "%#jx");
#undef CHK
if (bad) {
if (listerr == 0)
return (0);
if (preen)
printf("%s: ", cdevname);
printf(
"VALUES IN SUPER BLOCK LSB=%jd DISAGREE WITH THOSE IN\n"
"LAST ALTERNATE LSB=%jd\n",
sblk.b_bno, asblk.b_bno);
if (reply("IGNORE ALTERNATE SUPER BLOCK") == 0)
return (0);
}
out:
/*
* If not yet done, update UFS1 superblock with new wider fields.
*/
if (sblock.fs_magic == FS_UFS1_MAGIC &&
sblock.fs_maxbsize != sblock.fs_bsize) {
sblock.fs_maxbsize = sblock.fs_bsize;
sblock.fs_time = sblock.fs_old_time;
sblock.fs_size = sblock.fs_old_size;
sblock.fs_dsize = sblock.fs_old_dsize;
sblock.fs_csaddr = sblock.fs_old_csaddr;
sblock.fs_cstotal.cs_ndir = sblock.fs_old_cstotal.cs_ndir;
sblock.fs_cstotal.cs_nbfree = sblock.fs_old_cstotal.cs_nbfree;
sblock.fs_cstotal.cs_nifree = sblock.fs_old_cstotal.cs_nifree;
sblock.fs_cstotal.cs_nffree = sblock.fs_old_cstotal.cs_nffree;
}
havesb = 1;
return (1);
}
void
sblock_init(void)
{
fswritefd = -1;
fsmodified = 0;
lfdir = 0;
initbarea(&sblk, BT_SUPERBLK);
initbarea(&asblk, BT_SUPERBLK);
sblk.b_un.b_buf = Malloc(SBLOCKSIZE);
asblk.b_un.b_buf = Malloc(SBLOCKSIZE);
if (sblk.b_un.b_buf == NULL || asblk.b_un.b_buf == NULL)
errx(EEXIT, "cannot allocate space for superblock");
dev_bsize = secsize = DEV_BSIZE;
}
/*
* Calculate a prototype superblock based on information in the boot area.
* When done the cgsblock macro can be calculated and the fs_ncg field
* can be used. Do NOT attempt to use other macros without verifying that
* their needed information is available!
*/
static int
calcsb(char *dev, int devfd, struct fs *fs)
{
struct fsrecovery *fsr;
char *fsrbuf;
u_int secsize;
/*
* We need fragments-per-group and the partition-size.
*
* Newfs stores these details at the end of the boot block area
* at the start of the filesystem partition. If they have been
* overwritten by a boot block, we fail. But usually they are
* there and we can use them.
*/
if (ioctl(devfd, DIOCGSECTORSIZE, &secsize) == -1)
return (0);
fsrbuf = Malloc(secsize);
if (fsrbuf == NULL)
errx(EEXIT, "calcsb: cannot allocate recovery buffer");
if (blread(devfd, fsrbuf,
(SBLOCK_UFS2 - secsize) / dev_bsize, secsize) != 0)
return (0);
fsr = (struct fsrecovery *)&fsrbuf[secsize - sizeof *fsr];
if (fsr->fsr_magic != FS_UFS2_MAGIC)
return (0);
memset(fs, 0, sizeof(struct fs));
fs->fs_fpg = fsr->fsr_fpg;
fs->fs_fsbtodb = fsr->fsr_fsbtodb;
fs->fs_sblkno = fsr->fsr_sblkno;
fs->fs_magic = fsr->fsr_magic;
fs->fs_ncg = fsr->fsr_ncg;
free(fsrbuf);
return (1);
}
/*
* Check to see if recovery information exists.
* Return 1 if it exists or cannot be created.
* Return 0 if it does not exist and can be created.
*/
static int
chkrecovery(int devfd)
{
struct fsrecovery *fsr;
char *fsrbuf;
u_int secsize;
/*
* Could not determine if backup material exists, so do not
* offer to create it.
*/
if (ioctl(devfd, DIOCGSECTORSIZE, &secsize) == -1 ||
(fsrbuf = Malloc(secsize)) == NULL ||
blread(devfd, fsrbuf, (SBLOCK_UFS2 - secsize) / dev_bsize,
secsize) != 0)
return (1);
/*
* Recovery material has already been created, so do not
* need to create it again.
*/
fsr = (struct fsrecovery *)&fsrbuf[secsize - sizeof *fsr];
if (fsr->fsr_magic == FS_UFS2_MAGIC) {
free(fsrbuf);
return (1);
}
/*
* Recovery material has not been created and can be if desired.
*/
free(fsrbuf);
return (0);
}
/*
* Read the last sector of the boot block, replace the last
* 20 bytes with the recovery information, then write it back.
* The recovery information only works for UFS2 filesystems.
*/
static void
saverecovery(int readfd, int writefd)
{
struct fsrecovery *fsr;
char *fsrbuf;
u_int secsize;
if (sblock.fs_magic != FS_UFS2_MAGIC ||
ioctl(readfd, DIOCGSECTORSIZE, &secsize) == -1 ||
(fsrbuf = Malloc(secsize)) == NULL ||
blread(readfd, fsrbuf, (SBLOCK_UFS2 - secsize) / dev_bsize,
secsize) != 0) {
printf("RECOVERY DATA COULD NOT BE CREATED\n");
return;
}
fsr = (struct fsrecovery *)&fsrbuf[secsize - sizeof *fsr];
fsr->fsr_magic = sblock.fs_magic;
fsr->fsr_fpg = sblock.fs_fpg;
fsr->fsr_fsbtodb = sblock.fs_fsbtodb;
fsr->fsr_sblkno = sblock.fs_sblkno;
fsr->fsr_ncg = sblock.fs_ncg;
blwrite(writefd, fsrbuf, (SBLOCK_UFS2 - secsize) / secsize, secsize);
free(fsrbuf);
}