freebsd-nq/sbin/fsck_ffs/main.c
Kirk McKusick ff76fc7f16 Create a .snap directory mode 770 group operator in the root of each
filesystem that is checked in background. Create the snapshot in this
directory rather than in the root. There are two benefits:

1) For terabyte-sized filesystems, the snapshot may require many
   minutes to build. Although the filesystem will not be suspended
   during most of the snapshot build, the snapshot file itself is
   locked during the entire snapshot build period. Thus, if it is
   accessed during the period that it is being built, the process
   trying to access it will block holding its containing directory
   locked. If the snapshot is in the root, the root will lock and
   the system will come to a halt until the snapshot finishes. By
   putting the snapshot in a subdirectory, it is out of the likely
   path of any process traversing through the root and hence much
   less likely to cause a lock race to the root.

2) The dump program is usually run by a non-root user running with
   operator group privilege. Such a user is typically not permitted
   to create files in the root of a filesystem. By having a directory
   in group operator with group write access available, such a user
   will be able to create a snapshot there. Having the dump program
   create its snapshot in a subdirectory below the root will benefit
   from point (1) as well.

Sponsored by:   DARPA & NAI Labs.
2003-10-08 02:14:03 +00:00

541 lines
14 KiB
C

/*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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 copyright[] =
"@(#) Copyright (c) 1980, 1986, 1993\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
static char sccsid[] = "@(#)main.c 8.6 (Berkeley) 5/14/95";
#endif /* not lint */
#endif
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/stat.h>
#include <sys/file.h>
#include <sys/time.h>
#include <sys/mount.h>
#include <sys/resource.h>
#include <sys/sysctl.h>
#include <sys/disklabel.h>
#include <ufs/ufs/dinode.h>
#include <ufs/ufs/ufsmount.h>
#include <ufs/ffs/fs.h>
#include <err.h>
#include <errno.h>
#include <fstab.h>
#include <grp.h>
#include <paths.h>
#include <stdint.h>
#include <string.h>
#include "fsck.h"
static void usage(void) __dead2;
static int argtoi(int flag, const char *req, const char *str, int base);
static int checkfilesys(char *filesys);
static struct statfs *getmntpt(const char *);
int
main(int argc, char *argv[])
{
int ch;
struct rlimit rlimit;
int ret = 0;
sync();
skipclean = 1;
while ((ch = getopt(argc, argv, "b:Bc:dfFm:npy")) != -1) {
switch (ch) {
case 'b':
skipclean = 0;
bflag = argtoi('b', "number", optarg, 10);
printf("Alternate super block location: %d\n", bflag);
break;
case 'B':
bkgrdflag = 1;
break;
case 'c':
skipclean = 0;
cvtlevel = argtoi('c', "conversion level", optarg, 10);
if (cvtlevel < 3)
errx(EEXIT, "cannot do level %d conversion",
cvtlevel);
break;
case 'd':
debug++;
break;
case 'f':
skipclean = 0;
break;
case 'F':
bkgrdcheck = 1;
break;
case 'm':
lfmode = argtoi('m', "mode", optarg, 8);
if (lfmode &~ 07777)
errx(EEXIT, "bad mode to -m: %o", lfmode);
printf("** lost+found creation mode %o\n", lfmode);
break;
case 'n':
nflag++;
yflag = 0;
break;
case 'p':
preen++;
break;
case 'y':
yflag++;
nflag = 0;
break;
default:
usage();
}
}
argc -= optind;
argv += optind;
if (!argc)
usage();
if (signal(SIGINT, SIG_IGN) != SIG_IGN)
(void)signal(SIGINT, catch);
if (preen)
(void)signal(SIGQUIT, catchquit);
signal(SIGINFO, infohandler);
/*
* Push up our allowed memory limit so we can cope
* with huge file systems.
*/
if (getrlimit(RLIMIT_DATA, &rlimit) == 0) {
rlimit.rlim_cur = rlimit.rlim_max;
(void)setrlimit(RLIMIT_DATA, &rlimit);
}
while (argc-- > 0)
(void)checkfilesys(*argv++);
if (returntosingle)
ret = 2;
exit(ret);
}
static int
argtoi(int flag, const char *req, const char *str, int base)
{
char *cp;
int ret;
ret = (int)strtol(str, &cp, base);
if (cp == str || *cp)
errx(EEXIT, "-%c flag requires a %s", flag, req);
return (ret);
}
/*
* Check the specified file system.
*/
/* ARGSUSED */
static int
checkfilesys(char *filesys)
{
ufs2_daddr_t n_ffree, n_bfree;
struct ufs_args args;
struct dups *dp;
struct statfs *mntp;
struct zlncnt *zlnp;
struct stat snapdir;
struct group *grp;
ufs2_daddr_t blks;
int cylno, ret;
ino_t files;
size_t size;
cdevname = filesys;
if (debug && preen)
pwarn("starting\n");
/*
* Make best effort to get the disk name. Check first to see
* if it is listed among the mounted file systems. Failing that
* check to see if it is listed in /etc/fstab.
*/
mntp = getmntpt(filesys);
if (mntp != NULL)
filesys = mntp->f_mntfromname;
else
filesys = blockcheck(filesys);
/*
* If -F flag specified, check to see whether a background check
* is possible and needed. If possible and needed, exit with
* status zero. Otherwise exit with status non-zero. A non-zero
* exit status will cause a foreground check to be run.
*/
sblock_init();
if (bkgrdcheck) {
if ((fsreadfd = open(filesys, O_RDONLY)) < 0 || readsb(0) == 0)
exit(3); /* Cannot read superblock */
close(fsreadfd);
if (sblock.fs_flags & FS_NEEDSFSCK)
exit(4); /* Earlier background failed */
if ((sblock.fs_flags & FS_DOSOFTDEP) == 0)
exit(5); /* Not running soft updates */
size = MIBSIZE;
if (sysctlnametomib("vfs.ffs.adjrefcnt", adjrefcnt, &size) < 0)
exit(6); /* Lacks kernel support */
if ((mntp == NULL && sblock.fs_clean == 1) ||
(mntp != NULL && (sblock.fs_flags & FS_UNCLEAN) == 0))
exit(7); /* Filesystem clean, report it now */
exit(0);
}
/*
* If we are to do a background check:
* Get the mount point information of the file system
* create snapshot file
* return created snapshot file
* if not found, clear bkgrdflag and proceed with normal fsck
*/
if (bkgrdflag) {
if (mntp == NULL) {
bkgrdflag = 0;
pfatal("NOT MOUNTED, CANNOT RUN IN BACKGROUND\n");
} else if ((mntp->f_flags & MNT_SOFTDEP) == 0) {
bkgrdflag = 0;
pfatal("NOT USING SOFT UPDATES, %s\n",
"CANNOT RUN IN BACKGROUND");
} else if ((mntp->f_flags & MNT_RDONLY) != 0) {
bkgrdflag = 0;
pfatal("MOUNTED READ-ONLY, CANNOT RUN IN BACKGROUND\n");
} else if ((fsreadfd = open(filesys, O_RDONLY)) >= 0) {
if (readsb(0) != 0) {
if (sblock.fs_flags & FS_NEEDSFSCK) {
bkgrdflag = 0;
pfatal("UNEXPECTED INCONSISTENCY, %s\n",
"CANNOT RUN IN BACKGROUND\n");
}
if ((sblock.fs_flags & FS_UNCLEAN) == 0 &&
skipclean && preen) {
/*
* file system is clean;
* skip snapshot and report it clean
*/
pwarn("FILE SYSTEM CLEAN; %s\n",
"SKIPPING CHECKS");
goto clean;
}
}
close(fsreadfd);
}
if (bkgrdflag) {
snprintf(snapname, sizeof snapname, "%s/.snap",
mntp->f_mntonname);
if (stat(snapname, &snapdir) < 0) {
if (errno != ENOENT) {
bkgrdflag = 0;
pfatal("CANNOT FIND %s %s: %s, %s\n",
"SNAPSHOT DIRECTORY",
snapname, strerror(errno),
"CANNOT RUN IN BACKGROUND");
} else if ((grp = getgrnam("operator")) == 0 ||
mkdir(snapname, 0770) < 0 ||
chown(snapname, -1, grp->gr_gid) < 0 ||
chmod(snapname, 0770) < 0) {
bkgrdflag = 0;
pfatal("CANNOT CREATE %s %s: %s, %s\n",
"SNAPSHOT DIRECTORY",
snapname, strerror(errno),
"CANNOT RUN IN BACKGROUND");
}
} else if (!S_ISDIR(snapdir.st_mode)) {
bkgrdflag = 0;
pfatal("%s IS NOT A DIRECTORY, %s\n", snapname,
"CANNOT RUN IN BACKGROUND");
}
}
if (bkgrdflag) {
snprintf(snapname, sizeof snapname,
"%s/.snap/fsck_snapshot", mntp->f_mntonname);
args.fspec = snapname;
while (mount("ffs", mntp->f_mntonname,
mntp->f_flags | MNT_UPDATE | MNT_SNAPSHOT,
&args) < 0) {
if (errno == EEXIST && unlink(snapname) == 0)
continue;
bkgrdflag = 0;
pfatal("CANNOT CREATE SNAPSHOT %s: %s\n",
snapname, strerror(errno));
break;
}
if (bkgrdflag != 0)
filesys = snapname;
}
}
switch (setup(filesys)) {
case 0:
if (preen)
pfatal("CAN'T CHECK FILE SYSTEM.");
return (0);
case -1:
clean:
pwarn("clean, %ld free ", (long)(sblock.fs_cstotal.cs_nffree +
sblock.fs_frag * sblock.fs_cstotal.cs_nbfree));
printf("(%lld frags, %lld blocks, %.1f%% fragmentation)\n",
(long long)sblock.fs_cstotal.cs_nffree,
(long long)sblock.fs_cstotal.cs_nbfree,
sblock.fs_cstotal.cs_nffree * 100.0 / sblock.fs_dsize);
return (0);
}
/*
* Cleared if any questions answered no. Used to decide if
* the superblock should be marked clean.
*/
resolved = 1;
/*
* 1: scan inodes tallying blocks used
*/
if (preen == 0) {
printf("** Last Mounted on %s\n", sblock.fs_fsmnt);
if (mntp != NULL && mntp->f_flags & MNT_ROOTFS)
printf("** Root file system\n");
printf("** Phase 1 - Check Blocks and Sizes\n");
}
pass1();
/*
* 1b: locate first references to duplicates, if any
*/
if (duplist) {
if (preen || usedsoftdep)
pfatal("INTERNAL ERROR: dups with -p");
printf("** Phase 1b - Rescan For More DUPS\n");
pass1b();
}
/*
* 2: traverse directories from root to mark all connected directories
*/
if (preen == 0)
printf("** Phase 2 - Check Pathnames\n");
pass2();
/*
* 3: scan inodes looking for disconnected directories
*/
if (preen == 0)
printf("** Phase 3 - Check Connectivity\n");
pass3();
/*
* 4: scan inodes looking for disconnected files; check reference counts
*/
if (preen == 0)
printf("** Phase 4 - Check Reference Counts\n");
pass4();
/*
* 5: check and repair resource counts in cylinder groups
*/
if (preen == 0)
printf("** Phase 5 - Check Cyl groups\n");
pass5();
/*
* print out summary statistics
*/
n_ffree = sblock.fs_cstotal.cs_nffree;
n_bfree = sblock.fs_cstotal.cs_nbfree;
files = maxino - ROOTINO - sblock.fs_cstotal.cs_nifree - n_files;
blks = n_blks +
sblock.fs_ncg * (cgdmin(&sblock, 0) - cgsblock(&sblock, 0));
blks += cgsblock(&sblock, 0) - cgbase(&sblock, 0);
blks += howmany(sblock.fs_cssize, sblock.fs_fsize);
blks = maxfsblock - (n_ffree + sblock.fs_frag * n_bfree) - blks;
if (bkgrdflag && (files > 0 || blks > 0)) {
countdirs = sblock.fs_cstotal.cs_ndir - countdirs;
pwarn("Reclaimed: %ld directories, %ld files, %lld fragments\n",
countdirs, (long)files - countdirs, (long long)blks);
}
pwarn("%ld files, %jd used, %ju free ",
(long)n_files, (intmax_t)n_blks,
(uintmax_t)n_ffree + sblock.fs_frag * n_bfree);
printf("(%ju frags, %ju blocks, %.1f%% fragmentation)\n",
(uintmax_t)n_ffree, (uintmax_t)n_bfree,
n_ffree * 100.0 / sblock.fs_dsize);
if (debug) {
if (files < 0)
printf("%d inodes missing\n", -files);
if (blks < 0)
printf("%lld blocks missing\n", -(long long)blks);
if (duplist != NULL) {
printf("The following duplicate blocks remain:");
for (dp = duplist; dp; dp = dp->next)
printf(" %lld,", (long long)dp->dup);
printf("\n");
}
if (zlnhead != NULL) {
printf("The following zero link count inodes remain:");
for (zlnp = zlnhead; zlnp; zlnp = zlnp->next)
printf(" %u,", zlnp->zlncnt);
printf("\n");
}
}
zlnhead = (struct zlncnt *)0;
duplist = (struct dups *)0;
muldup = (struct dups *)0;
inocleanup();
if (fsmodified) {
sblock.fs_time = time(NULL);
sbdirty();
}
if (cvtlevel && sblk.b_dirty) {
/*
* Write out the duplicate super blocks
*/
for (cylno = 0; cylno < sblock.fs_ncg; cylno++)
bwrite(fswritefd, (char *)&sblock,
fsbtodb(&sblock, cgsblock(&sblock, cylno)),
SBLOCKSIZE);
}
if (rerun)
resolved = 0;
/*
* Check to see if the file system is mounted read-write.
*/
if (bkgrdflag == 0 && mntp != NULL && (mntp->f_flags & MNT_RDONLY) == 0)
resolved = 0;
ckfini(resolved);
for (cylno = 0; cylno < sblock.fs_ncg; cylno++)
if (inostathead[cylno].il_stat != NULL)
free((char *)inostathead[cylno].il_stat);
free((char *)inostathead);
inostathead = NULL;
if (fsmodified && !preen)
printf("\n***** FILE SYSTEM WAS MODIFIED *****\n");
if (rerun)
printf("\n***** PLEASE RERUN FSCK *****\n");
if (mntp != NULL) {
/*
* We modified a mounted file system. Do a mount update on
* it unless it is read-write, so we can continue using it
* as safely as possible.
*/
if (mntp->f_flags & MNT_RDONLY) {
args.fspec = 0;
args.export.ex_flags = 0;
args.export.ex_root = 0;
ret = mount("ufs", mntp->f_mntonname,
mntp->f_flags | MNT_UPDATE | MNT_RELOAD, &args);
if (ret == 0)
return (0);
pwarn("mount reload of '%s' failed: %s\n\n",
mntp->f_mntonname, strerror(errno));
}
if (!fsmodified)
return (0);
if (!preen)
printf("\n***** REBOOT NOW *****\n");
sync();
return (4);
}
return (0);
}
/*
* Get the mount point information for name.
*/
static struct statfs *
getmntpt(const char *name)
{
struct stat devstat, mntdevstat;
char device[sizeof(_PATH_DEV) - 1 + MNAMELEN];
char *ddevname;
struct statfs *mntbuf, *statfsp;
int i, mntsize, isdev;
if (stat(name, &devstat) != 0)
return (NULL);
if (S_ISCHR(devstat.st_mode) || S_ISBLK(devstat.st_mode))
isdev = 1;
else
isdev = 0;
mntsize = getmntinfo(&mntbuf, MNT_NOWAIT);
for (i = 0; i < mntsize; i++) {
statfsp = &mntbuf[i];
ddevname = statfsp->f_mntfromname;
if (*ddevname != '/') {
strcpy(device, _PATH_DEV);
strcat(device, ddevname);
strcpy(statfsp->f_mntfromname, device);
}
if (isdev == 0) {
if (strcmp(name, statfsp->f_mntonname))
continue;
return (statfsp);
}
if (stat(ddevname, &mntdevstat) == 0 &&
mntdevstat.st_rdev == devstat.st_rdev)
return (statfsp);
}
statfsp = NULL;
return (statfsp);
}
static void
usage(void)
{
(void) fprintf(stderr,
"usage: %s [-BFpfny] [-b block] [-c level] [-m mode] "
"file system ...\n",
getprogname());
exit(1);
}