NetBSD/sbin/newfs_ext2fs/mke2fs.c
2008-05-14 13:29:27 +00:00

1432 lines
43 KiB
C

/* $NetBSD: mke2fs.c,v 1.8 2008/05/14 13:29:27 tsutsui Exp $ */
/*-
* Copyright (c) 2007 Izumi Tsutsui. 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*/
/*
* Copyright (c) 1980, 1989, 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.
*/
/*
* Copyright (c) 1997 Manuel Bouyer.
*
* 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 Manuel Bouyer.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*/
/*
* mke2fs.c: "re-invent (dumb but non-GPLed) wheel as a fun project"
*
* In spite of this name, there is no piece of code
* derived from GPLed e2fsprogs written for Linux.
* I referred them only to see how each structure
* member should be initialized.
*
* Reference:
* - All NetBSD sources under src/sys/ufs/ext2fs and src/sbin/fsck_ext2fs
* - Ext2fs Home Page
* http://e2fsprogs.sourceforge.net/ext2.html
* - Design and Implementation of the Second Extended Filesystem
* http://e2fsprogs.sourceforge.net/ext2intro.html
* - Linux Documentation "The Second Extended Filesystem"
* src/linux/Documentation/filesystems/ext2.txt
* in the Linux kernel distribution
*/
#include <sys/cdefs.h>
#ifndef lint
#if 0
static char sccsid[] = "@(#)mkfs.c 8.11 (Berkeley) 5/3/95";
#else
__RCSID("$NetBSD: mke2fs.c,v 1.8 2008/05/14 13:29:27 tsutsui Exp $");
#endif
#endif /* not lint */
#include <sys/param.h>
#include <sys/mman.h>
#include <sys/time.h>
#include <ufs/ext2fs/ext2fs_dinode.h>
#include <ufs/ext2fs/ext2fs_dir.h>
#include <ufs/ext2fs/ext2fs.h>
#include <sys/ioctl.h>
#include <err.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
#include <stdlib.h>
#include <stddef.h>
#include <stdio.h>
#include <uuid.h>
#include "extern.h"
static void initcg(uint);
static void zap_old_sblock(daddr_t);
static uint cgoverhead(uint);
static int fsinit(const struct timeval *);
static int makedir(struct ext2fs_direct *, int);
static void copy_dir(struct ext2fs_direct *, struct ext2fs_direct *);
static void init_resizeino(const struct timeval *);
static uint32_t alloc(uint32_t, uint16_t);
static void iput(struct ext2fs_dinode *, ino_t);
static void rdfs(daddr_t, int, void *);
static void wtfs(daddr_t, int, void *);
static int ilog2(uint);
static int skpc(int, size_t, uint8_t *);
/* XXX: some of these macro should be into <ufs/ext2fs/ext2fs.h>? */
#define EXT2_DEF_MAX_MNT_COUNT 20
#define EXT2_DEF_FSCKINTV (180 * 24 * 60 * 60) /* 180 days */
#define EXT2_RESERVED_INODES (EXT2_FIRSTINO - 1)
#define EXT2_UMASK 0755
#define EXT2_INO_INDEX(ino) ((ino) - 1) /* no inode zero */
#define EXT2_LOSTFOUNDSIZE 16384
#define EXT2_LOSTFOUNDINO EXT2_FIRSTINO /* XXX: not quite */
#define EXT2_LOSTFOUNDUMASK 0700
#define EXT2_RESIZEINOUMASK 0600
#define NBLOCK_SUPERBLOCK 1
#define NBLOCK_BLOCK_BITMAP 1
#define NBLOCK_INODE_BITMAP 1
#define cgbase(fs, c) \
((fs)->e2fs.e2fs_first_dblock + (fs)->e2fs.e2fs_bpg * (c))
/*
* ext2fs super block and group descriptor structures
*
* We don't have to use or setup whole in-memory m_ext2fs structure,
* but prepare it to use several macro defined in kernel headers.
*/
union {
struct m_ext2fs m_ext2fs;
char pad[SBSIZE];
} ext2fsun;
#define sblock ext2fsun.m_ext2fs
#define gd ext2fsun.m_ext2fs.e2fs_gd
static uint8_t *iobuf; /* for superblock and group descriptors */
static int iobufsize;
static uint8_t buf[MAXBSIZE]; /* for initcg() and makedir() ops */
static int fsi, fso;
void
mke2fs(const char *fsys, int fi, int fo)
{
struct timeval tv;
int64_t minfssize;
uint bcount, fbcount, ficount;
uint blocks_gd, blocks_per_cg, inodes_per_cg, iblocks_per_cg;
uint minblocks_per_cg, blocks_lastcg;
uint ncg, cylno, sboff;
uuid_t uuid;
uint32_t uustat;
int i, len, col, delta, fld_width, max_cols;
struct winsize winsize;
gettimeofday(&tv, NULL);
fsi = fi;
fso = fo;
/*
* collect and verify the block and fragment sizes
*/
if (!powerof2(bsize)) {
errx(EXIT_FAILURE,
"block size must be a power of 2, not %u\n",
bsize);
}
if (!powerof2(fsize)) {
errx(EXIT_FAILURE,
"fragment size must be a power of 2, not %u\n",
fsize);
}
if (fsize < sectorsize) {
errx(EXIT_FAILURE,
"fragment size %u is too small, minimum is %u\n",
fsize, sectorsize);
}
if (bsize < MINBSIZE) {
errx(EXIT_FAILURE,
"block size %u is too small, minimum is %u\n",
bsize, MINBSIZE);
}
if (bsize > EXT2_MAXBSIZE) {
errx(EXIT_FAILURE,
"block size %u is too large, maximum is %u\n",
bsize, MAXBSIZE);
}
if (bsize != fsize) {
/*
* There is no fragment support on current ext2fs (yet?),
* but some kernel code refers fsize or fpg as bsize or bpg
* and Linux seems to set the same values to them.
*/
errx(EXIT_FAILURE,
"block size (%u) can't be diffrent from "
"fragment size (%u)\n",
bsize, fsize);
}
sblock.e2fs.e2fs_log_bsize = ilog2(bsize) - LOG_MINBSIZE;
/* Umm, why not e2fs_log_fsize? */
sblock.e2fs.e2fs_fsize = ilog2(fsize) - LOG_MINBSIZE;
sblock.e2fs_bsize = bsize;
sblock.e2fs_bshift = sblock.e2fs.e2fs_log_bsize + LOG_MINBSIZE;
sblock.e2fs_qbmask = sblock.e2fs_bsize - 1;
sblock.e2fs_bmask = ~sblock.e2fs_qbmask;
sblock.e2fs_fsbtodb = ilog2(sblock.e2fs_bsize) - ilog2(sectorsize);
sblock.e2fs_ipb = sblock.e2fs_bsize / EXT2_DINODE_SIZE;
/*
* Ext2fs preseves BBSIZE (1024 bytes) space at the top for
* bootloader (though it is not enough at all for our bootloader).
* If bsize == BBSIZE we have to preserve one block.
* If bsize > BBSIZE, the first block already contains BBSIZE space
* before superblock because superblock is allocated at SBOFF and
* bsize is a power of two (i.e. 2048 bytes or more).
*/
sblock.e2fs.e2fs_first_dblock = (sblock.e2fs_bsize > BBSIZE) ? 0 : 1;
minfssize = fsbtodb(&sblock,
sblock.e2fs.e2fs_first_dblock +
NBLOCK_SUPERBLOCK +
1 /* at least one group descriptor */ +
NBLOCK_BLOCK_BITMAP +
NBLOCK_INODE_BITMAP +
1 /* at least one inode table block */ +
1 /* at least one data block for rootdir */ +
1 /* at least one data block for data */
); /* XXX and more? */
if (fssize < minfssize)
errx(EXIT_FAILURE, "Filesystem size %" PRId64
" < minimum size of %" PRId64 "\n", fssize, minfssize);
bcount = dbtofsb(&sblock, fssize);
/*
* While many people claim that ext2fs is a (bad) clone of ufs/ffs,
* it isn't actual ffs so maybe we should call it "block group"
* as their native name rather than ffs delived "cylinder group."
* But we'll use the latter here since other kernel sources use it.
* (I also agree "cylinder" based allocation is obsolete though)
*/
/* maybe "simple is the best" */
blocks_per_cg = sblock.e2fs_bsize * NBBY;
ncg = howmany(bcount - sblock.e2fs.e2fs_first_dblock, blocks_per_cg);
blocks_gd = howmany(sizeof(struct ext2_gd) * ncg, bsize);
/* check range of inode number */
if (num_inodes < EXT2_FIRSTINO)
num_inodes = EXT2_FIRSTINO; /* needs reserved inodes + 1 */
if (num_inodes > UINT16_MAX * ncg)
num_inodes = UINT16_MAX * ncg; /* ext2bgd_nifree is uint16_t */
inodes_per_cg = num_inodes / ncg;
iblocks_per_cg = howmany(EXT2_DINODE_SIZE * inodes_per_cg, bsize);
/* Check that the last cylinder group has enough space for inodes */
minblocks_per_cg =
NBLOCK_BLOCK_BITMAP +
NBLOCK_INODE_BITMAP +
iblocks_per_cg +
1; /* at least one data block */
if (Oflag == 0 || cg_has_sb(ncg - 1) != 0)
minblocks_per_cg += NBLOCK_SUPERBLOCK + blocks_gd;
blocks_lastcg = bcount - sblock.e2fs.e2fs_first_dblock -
blocks_per_cg * (ncg - 1);
if (blocks_lastcg < minblocks_per_cg) {
/*
* Since we make all the cylinder groups the same size, the
* last will only be small if there are more than one
* cylinder groups. If the last one is too small to store
* filesystem data, just kill it.
*
* XXX: Does fsck_ext2fs(8) properly handle this case?
*/
bcount -= blocks_lastcg;
ncg--;
blocks_lastcg = blocks_per_cg;
blocks_gd = howmany(sizeof(struct ext2_gd) * ncg, bsize);
inodes_per_cg = num_inodes / ncg;
}
/* roundup inodes_per_cg to make it use whole inode table blocks */
inodes_per_cg = roundup(inodes_per_cg, sblock.e2fs_ipb);
num_inodes = inodes_per_cg * ncg;
iblocks_per_cg = inodes_per_cg / sblock.e2fs_ipb;
/* XXX: probably we should check these adjusted values again */
sblock.e2fs.e2fs_bcount = bcount;
sblock.e2fs.e2fs_icount = num_inodes;
sblock.e2fs_ncg = ncg;
sblock.e2fs_ngdb = blocks_gd;
sblock.e2fs_itpg = iblocks_per_cg;
sblock.e2fs.e2fs_rbcount = sblock.e2fs.e2fs_bcount * minfree / 100;
/* e2fs_fbcount will be accounted later */
/* e2fs_ficount will be accounted later */
sblock.e2fs.e2fs_bpg = blocks_per_cg;
sblock.e2fs.e2fs_fpg = blocks_per_cg;
sblock.e2fs.e2fs_ipg = inodes_per_cg;
sblock.e2fs.e2fs_mtime = 0;
sblock.e2fs.e2fs_wtime = tv.tv_sec;
sblock.e2fs.e2fs_mnt_count = 0;
/* XXX: should add some entropy to avoid checking all fs at once? */
sblock.e2fs.e2fs_max_mnt_count = EXT2_DEF_MAX_MNT_COUNT;
sblock.e2fs.e2fs_magic = E2FS_MAGIC;
sblock.e2fs.e2fs_state = E2FS_ISCLEAN;
sblock.e2fs.e2fs_beh = E2FS_BEH_DEFAULT;
sblock.e2fs.e2fs_minrev = 0;
sblock.e2fs.e2fs_lastfsck = tv.tv_sec;
sblock.e2fs.e2fs_fsckintv = EXT2_DEF_FSCKINTV;
/*
* Maybe we can use E2FS_OS_FREEBSD here and it would be more proper,
* but the purpose of this newfs_ext2fs(8) command is to provide
* a filesystem which can be recognized by firmwares on some
* Linux based appliances that can load bootstrap files only from
* (their native) ext2fs, and anyway we will (and should) try to
* act like them as much as possible.
*
* Anyway, I hope that all newer such boxes will keep their support
* for the "GOOD_OLD_REV" ext2fs.
*/
sblock.e2fs.e2fs_creator = E2FS_OS_LINUX;
if (Oflag == 0) {
sblock.e2fs.e2fs_rev = E2FS_REV0;
sblock.e2fs.e2fs_features_compat = 0;
sblock.e2fs.e2fs_features_incompat = 0;
sblock.e2fs.e2fs_features_rocompat = 0;
} else {
sblock.e2fs.e2fs_rev = E2FS_REV1;
/*
* e2fsprogs say "REV1" is "dynamic" so
* it isn't quite a version and maybe it means
* "extended from REV0 so check compat features."
*
* XXX: We don't have any native tool to activate
* the EXT2F_COMPAT_RESIZE feature and
* fsck_ext2fs(8) might not fix structures for it.
*/
sblock.e2fs.e2fs_features_compat = EXT2F_COMPAT_RESIZE;
sblock.e2fs.e2fs_features_incompat = EXT2F_INCOMPAT_FTYPE;
sblock.e2fs.e2fs_features_rocompat =
EXT2F_ROCOMPAT_SPARSESUPER | EXT2F_ROCOMPAT_LARGEFILE;
}
sblock.e2fs.e2fs_ruid = geteuid();
sblock.e2fs.e2fs_rgid = getegid();
sblock.e2fs.e2fs_first_ino = EXT2_FIRSTINO;
sblock.e2fs.e2fs_inode_size = EXT2_DINODE_SIZE;
/* e2fs_block_group_nr is set on writing superblock to each group */
uuid_create(&uuid, &uustat);
if (uustat != uuid_s_ok)
errx(EXIT_FAILURE, "Failed to generate uuid\n");
uuid_enc_le(sblock.e2fs.e2fs_uuid, &uuid);
if (volname != NULL) {
if (strlen(volname) > sizeof(sblock.e2fs.e2fs_vname))
errx(EXIT_FAILURE, "Volume name is too long");
strlcpy(sblock.e2fs.e2fs_vname, volname,
sizeof(sblock.e2fs.e2fs_vname));
}
sblock.e2fs.e2fs_fsmnt[0] = '\0';
sblock.e2fs_fsmnt[0] = '\0';
sblock.e2fs.e2fs_algo = 0; /* XXX unsupported? */
sblock.e2fs.e2fs_prealloc = 0; /* XXX unsupported? */
sblock.e2fs.e2fs_dir_prealloc = 0; /* XXX unsupported? */
/* calculate blocks for reserved group descriptors for resize */
sblock.e2fs.e2fs_reserved_ngdb = 0;
if (sblock.e2fs.e2fs_rev > E2FS_REV0 &&
(sblock.e2fs.e2fs_features_compat & EXT2F_COMPAT_RESIZE) != 0) {
uint64_t target_blocks;
uint target_ncg, target_ngdb, reserved_ngdb;
/* reserve descriptors for size as 1024 times as current */
target_blocks =
(sblock.e2fs.e2fs_bcount - sblock.e2fs.e2fs_first_dblock)
* 1024ULL;
/* number of blocks must be in uint32_t */
if (target_blocks > UINT32_MAX)
target_blocks = UINT32_MAX;
target_ncg = howmany(target_blocks, sblock.e2fs.e2fs_bpg);
target_ngdb = howmany(sizeof(struct ext2_gd) * target_ncg,
sblock.e2fs_bsize);
/*
* Reserved group descriptor blocks are preserved as
* the second level double indirect reference blocks in
* the EXT2_RESIZEINO inode, so the maximum number of
* the blocks is NINDIR(fs).
* (see also descriptions in init_resizeino() function)
*
* We check a number including current e2fs_ngdb here
* because they will be moved into reserved gdb on
* possible future size shrink, though e2fsprogs don't
* seem to care about it.
*/
if (target_ngdb > NINDIR(&sblock))
target_ngdb = NINDIR(&sblock);
reserved_ngdb = target_ngdb - sblock.e2fs_ngdb;
/* make sure reserved_ngdb fits in the last cg */
if (reserved_ngdb >= blocks_lastcg - cgoverhead(ncg - 1))
reserved_ngdb = blocks_lastcg - cgoverhead(ncg - 1);
if (reserved_ngdb == 0) {
/* if no space for reserved gdb, disable the feature */
sblock.e2fs.e2fs_features_compat &=
~EXT2F_COMPAT_RESIZE;
}
sblock.e2fs.e2fs_reserved_ngdb = reserved_ngdb;
}
/*
* Initialize group descriptors
*/
gd = malloc(sblock.e2fs_ngdb * bsize);
if (gd == NULL)
errx(EXIT_FAILURE, "Can't allocate descriptors buffer");
memset(gd, 0, sblock.e2fs_ngdb * bsize);
fbcount = 0;
ficount = 0;
for (cylno = 0; cylno < ncg; cylno++) {
uint boffset;
boffset = cgbase(&sblock, cylno);
if (sblock.e2fs.e2fs_rev == E2FS_REV0 ||
(sblock.e2fs.e2fs_features_rocompat &
EXT2F_ROCOMPAT_SPARSESUPER) == 0 ||
cg_has_sb(cylno)) {
boffset += NBLOCK_SUPERBLOCK + sblock.e2fs_ngdb;
if (sblock.e2fs.e2fs_rev > E2FS_REV0 &&
(sblock.e2fs.e2fs_features_compat &
EXT2F_COMPAT_RESIZE) != 0)
boffset += sblock.e2fs.e2fs_reserved_ngdb;
}
gd[cylno].ext2bgd_b_bitmap = boffset;
boffset += NBLOCK_BLOCK_BITMAP;
gd[cylno].ext2bgd_i_bitmap = boffset;
boffset += NBLOCK_INODE_BITMAP;
gd[cylno].ext2bgd_i_tables = boffset;
if (cylno == (ncg - 1))
gd[cylno].ext2bgd_nbfree =
blocks_lastcg - cgoverhead(cylno);
else
gd[cylno].ext2bgd_nbfree =
sblock.e2fs.e2fs_bpg - cgoverhead(cylno);
fbcount += gd[cylno].ext2bgd_nbfree;
gd[cylno].ext2bgd_nifree = sblock.e2fs.e2fs_ipg;
if (cylno == 0) {
/* take reserved inodes off nifree */
gd[cylno].ext2bgd_nifree -= EXT2_RESERVED_INODES;
}
ficount += gd[cylno].ext2bgd_nifree;
gd[cylno].ext2bgd_ndirs = 0;
}
sblock.e2fs.e2fs_fbcount = fbcount;
sblock.e2fs.e2fs_ficount = ficount;
/*
* Dump out summary information about file system.
*/
if (verbosity > 0) {
printf("%s: %u.%1uMB (%" PRId64 " sectors) "
"block size %u, fragment size %u\n",
fsys,
(uint)(((uint64_t)bcount * bsize) / (1024 * 1024)),
(uint)((uint64_t)bcount * bsize -
rounddown((uint64_t)bcount * bsize, 1024 * 1024))
/ 1024 / 100,
fssize, bsize, fsize);
printf("\tusing %u block groups of %u.0MB, %u blks, "
"%u inodes.\n",
ncg, bsize * sblock.e2fs.e2fs_bpg / (1024 * 1024),
sblock.e2fs.e2fs_bpg, sblock.e2fs.e2fs_ipg);
}
/*
* allocate space for superblock and group descriptors
*/
iobufsize = (NBLOCK_SUPERBLOCK + sblock.e2fs_ngdb) * sblock.e2fs_bsize;
iobuf = mmap(0, iobufsize, PROT_READ|PROT_WRITE,
MAP_ANON|MAP_PRIVATE, -1, 0);
if (iobuf == NULL)
errx(EXIT_FAILURE, "Cannot allocate I/O buffer\n");
memset(iobuf, 0, iobufsize);
/*
* We now start writing to the filesystem
*/
if (!Nflag) {
static const uint pbsize[] = { 1024, 2048, 4096, 0 };
uint pblock, epblock;
/*
* Validate the given file system size.
* Verify that its last block can actually be accessed.
* Convert to file system fragment sized units.
*/
if (fssize <= 0)
errx(EXIT_FAILURE, "Preposterous size %" PRId64 "\n",
fssize);
wtfs(fssize - 1, sectorsize, iobuf);
/*
* Ensure there is nothing that looks like a filesystem
* superbock anywhere other than where ours will be.
* If fsck_ext2fs finds the wrong one all hell breaks loose!
*
* XXX: needs to check how fsck_ext2fs programs even
* on other OSes determine alternate superblocks
*/
for (i = 0; pbsize[i] != 0; i++) {
epblock = (uint64_t)bcount * bsize / pbsize[i];
for (pblock = ((pbsize[i] == SBSIZE) ? 1 : 0);
pblock < epblock;
pblock += pbsize[i] * NBBY /* bpg */)
zap_old_sblock((daddr_t)pblock *
pbsize[i] / sectorsize);
}
}
if (verbosity >= 3)
printf("super-block backups (for fsck_ext2fs -b #) at:\n");
/* If we are printing more than one line of numbers, line up columns */
fld_width = verbosity < 4 ? 1 : snprintf(NULL, 0, "%" PRIu64,
(uint64_t)cgbase(&sblock, ncg - 1));
/* Get terminal width */
if (ioctl(fileno(stdout), TIOCGWINSZ, &winsize) == 0)
max_cols = winsize.ws_col;
else
max_cols = 80;
if (Nflag && verbosity == 3)
/* Leave space to add " ..." after one row of numbers */
max_cols -= 4;
#define BASE 0x10000 /* For some fixed-point maths */
col = 0;
delta = verbosity > 2 ? 0 : max_cols * BASE / ncg;
for (cylno = 0; cylno < ncg; cylno++) {
fflush(stdout);
initcg(cylno);
if (verbosity < 2)
continue;
/* the first one is a master, not backup */
if (cylno == 0)
continue;
/* skip if this cylinder doesn't have a backup */
if (sblock.e2fs.e2fs_rev > E2FS_REV0 &&
(sblock.e2fs.e2fs_features_rocompat &
EXT2F_ROCOMPAT_SPARSESUPER) != 0 &&
cg_has_sb(cylno) == 0)
continue;
if (delta > 0) {
if (Nflag)
/* No point doing dots for -N */
break;
/* Print dots scaled to end near RH margin */
for (col += delta; col > BASE; col -= BASE)
printf(".");
continue;
}
/* Print superblock numbers */
len = printf(" %*" PRIu64 "," + !col, fld_width,
(uint64_t)cgbase(&sblock, cylno));
col += len;
if (col + len < max_cols)
/* Next number fits */
continue;
/* Next number won't fit, need a newline */
if (verbosity <= 3) {
/* Print dots for subsequent cylinder groups */
delta = sblock.e2fs_ncg - cylno - 1;
if (delta != 0) {
if (Nflag) {
printf(" ...");
break;
}
delta = max_cols * BASE / delta;
}
}
col = 0;
printf("\n");
}
#undef BASE
if (col > 0)
printf("\n");
if (Nflag)
return;
/*
* Now construct the initial file system,
*/
if (fsinit(&tv) == 0)
errx(EXIT_FAILURE, "Error making filesystem");
/*
* Write out the superblock and group descriptors
*/
sblock.e2fs.e2fs_block_group_nr = 0;
sboff = 0;
if (cgbase(&sblock, 0) == 0) {
/*
* If the first block contains the boot block sectors,
* (i.e. in case of sblock.e2fs.e2fs_bsize > BBSIZE)
* we have to preserve data in it.
*/
sboff = SBOFF;
}
e2fs_sbsave(&sblock.e2fs, (struct ext2fs *)(iobuf + sboff));
e2fs_cgsave(gd, (struct ext2_gd *)(iobuf + sblock.e2fs_bsize),
sizeof(struct ext2_gd) * sblock.e2fs_ncg);
wtfs(fsbtodb(&sblock, cgbase(&sblock, 0)) + sboff / sectorsize,
iobufsize - sboff, iobuf + sboff);
munmap(iobuf, iobufsize);
}
/*
* Initialize a cylinder (block) group.
*/
void
initcg(uint cylno)
{
uint nblcg, i, j, sboff;
struct ext2fs_dinode *dp;
/*
* Make a copy of the superblock and group descriptors.
*/
if (sblock.e2fs.e2fs_rev == E2FS_REV0 ||
(sblock.e2fs.e2fs_features_rocompat &
EXT2F_ROCOMPAT_SPARSESUPER) == 0 ||
cg_has_sb(cylno)) {
sblock.e2fs.e2fs_block_group_nr = cylno;
sboff = 0;
if (cgbase(&sblock, cylno) == 0) {
/* preserve data in bootblock in cg0 */
sboff = SBOFF;
}
e2fs_sbsave(&sblock.e2fs, (struct ext2fs *)(iobuf + sboff));
e2fs_cgsave(gd, (struct ext2_gd *)(iobuf +
sblock.e2fs_bsize * NBLOCK_SUPERBLOCK),
sizeof(struct ext2_gd) * sblock.e2fs_ncg);
/* write superblock and group descriptor backups */
wtfs(fsbtodb(&sblock, cgbase(&sblock, cylno)) +
sboff / sectorsize, iobufsize - sboff, iobuf + sboff);
}
/*
* Initialize block bitmap.
*/
memset(buf, 0, sblock.e2fs_bsize);
if (cylno == (sblock.e2fs_ncg - 1)) {
/* The last group could have less blocks than e2fs_bpg. */
nblcg = sblock.e2fs.e2fs_bcount -
cgbase(&sblock, sblock.e2fs_ncg - 1);
for (i = nblcg; i < roundup(nblcg, NBBY); i++)
setbit(buf, i);
memset(&buf[i / NBBY], ~0U, sblock.e2fs.e2fs_bpg - i);
}
/* set overhead (superblock, group descriptor etc.) blocks used */
for (i = 0; i < cgoverhead(cylno) / NBBY; i++)
buf[i] = ~0;
i = i * NBBY;
for (; i < cgoverhead(cylno); i++)
setbit(buf, i);
wtfs(fsbtodb(&sblock, gd[cylno].ext2bgd_b_bitmap), sblock.e2fs_bsize,
buf);
/*
* Initialize inode bitmap.
*
* Assume e2fs_ipg is a multiple of NBBY since
* it's a multible of e2fs_ipb (as we did above).
* Note even (possibly smaller) the last group has the same e2fs_ipg.
*/
i = sblock.e2fs.e2fs_ipg / NBBY;
memset(buf, 0, i);
memset(buf + i, ~0U, sblock.e2fs_bsize - i);
if (cylno == 0) {
/* mark reserved inodes */
for (i = 1; i < EXT2_FIRSTINO; i++)
setbit(buf, EXT2_INO_INDEX(i));
}
wtfs(fsbtodb(&sblock, gd[cylno].ext2bgd_i_bitmap), sblock.e2fs_bsize,
buf);
/*
* Initialize inode tables.
*
* Just initialize generation numbers for NFS security.
* XXX: sys/ufs/ext2fs/ext2fs_alloc.c:ext2fs_valloc() seems
* to override these generated numbers.
*/
memset(buf, 0, sblock.e2fs_bsize);
dp = (struct ext2fs_dinode *)buf;
for (i = 0; i < sblock.e2fs_itpg; i++) {
for (j = 0; j < sblock.e2fs_ipb; j++) {
/* h2fs32() just for consistency */
dp[j].e2di_gen = h2fs32(arc4random());
}
wtfs(fsbtodb(&sblock, gd[cylno].ext2bgd_i_tables + i),
sblock.e2fs_bsize, buf);
}
}
/*
* Zap possible lingering old superblock data
*/
static void
zap_old_sblock(daddr_t sec)
{
static daddr_t cg0_data;
uint32_t oldfs[SBSIZE / sizeof(uint32_t)];
static const struct fsm {
uint32_t offset;
uint32_t magic;
uint32_t mask;
} fs_magics[] = {
{offsetof(struct ext2fs, e2fs_magic) / 4, E2FS_MAGIC, 0xffff},
{offsetof(struct ext2fs, e2fs_magic) / 4,
E2FS_MAGIC << 16, 0xffff0000},
{14, 0xef530000, 0xffff0000}, /* EXT2FS (big) */
{0x55c / 4, 0x00011954, ~0U}, /* FS_UFS1_MAGIC */
{0x55c / 4, 0x19540119, ~0U}, /* FS_UFS2_MAGIC */
{0, 0x70162, ~0U}, /* LFS_MAGIC */
{.offset = ~0U},
};
const struct fsm *fsm;
if (Nflag)
return;
/* don't override data before superblock */
if (sec < SBOFF / sectorsize)
return;
if (cg0_data == 0) {
cg0_data =
((daddr_t)sblock.e2fs.e2fs_first_dblock + cgoverhead(0)) *
sblock.e2fs_bsize / sectorsize;
}
/* Ignore anything that is beyond our filesystem */
if (sec >= fssize)
return;
/* Zero anything inside our filesystem... */
if (sec >= sblock.e2fs.e2fs_first_dblock * bsize / sectorsize) {
/* ...unless we will write that area anyway */
if (sec >= cg0_data)
/* assume iobuf is zero'ed here */
wtfs(sec, roundup(SBSIZE, sectorsize), iobuf);
return;
}
/*
* The sector might contain boot code, so we must validate it
*
* XXX: ext2fs won't preserve data after SBOFF,
* but first_dblock could have a differnt value.
*/
rdfs(sec, sizeof(oldfs), &oldfs);
for (fsm = fs_magics;; fsm++) {
uint32_t v;
if (fsm->mask == 0)
return;
v = oldfs[fsm->offset];
if ((v & fsm->mask) == fsm->magic ||
(bswap32(v) & fsm->mask) == fsm->magic)
break;
}
/* Just zap the magic number */
oldfs[fsm->offset] = 0;
wtfs(sec, sizeof(oldfs), &oldfs);
}
/*
* uint cgoverhead(uint c)
*
* Return a number of reserved blocks on the specified group.
* XXX: should be shared with src/sbin/fsck_ext2fs/setup.c
*/
uint
cgoverhead(uint c)
{
uint overh;
overh = NBLOCK_BLOCK_BITMAP + NBLOCK_INODE_BITMAP + sblock.e2fs_itpg;
if (sblock.e2fs.e2fs_rev == E2FS_REV0 ||
(sblock.e2fs.e2fs_features_rocompat &
EXT2F_ROCOMPAT_SPARSESUPER) == 0 ||
cg_has_sb(c) != 0) {
overh += NBLOCK_SUPERBLOCK + sblock.e2fs_ngdb;
if (sblock.e2fs.e2fs_rev > E2FS_REV0 &&
(sblock.e2fs.e2fs_features_compat &
EXT2F_COMPAT_RESIZE) != 0)
overh += sblock.e2fs.e2fs_reserved_ngdb;
}
return overh;
}
/*
* Initialize the file system
*/
#define LOSTDIR /* e2fsck complains if there is no lost+found */
#define PREDEFDIR 2
#ifdef LOSTDIR
#define PREDEFROOTDIR (PREDEFDIR + 1)
#else
#define PREDEFROOTDIR PREDEFDIR
#endif
struct ext2fs_direct root_dir[] = {
{ EXT2_ROOTINO, 0, 1, 0, "." },
{ EXT2_ROOTINO, 0, 2, 0, ".." },
#ifdef LOSTDIR
{ EXT2_LOSTFOUNDINO, 0, 10, 0, "lost+found" },
#endif
};
#ifdef LOSTDIR
struct ext2fs_direct lost_found_dir[] = {
{ EXT2_LOSTFOUNDINO, 0, 1, 0, "." },
{ EXT2_ROOTINO, 0, 2, 0, ".." },
};
struct ext2fs_direct pad_dir = { 0, sizeof(struct ext2fs_direct), 0, 0, "" };
#endif
int
fsinit(const struct timeval *tv)
{
struct ext2fs_dinode node;
#ifdef LOSTDIR
uint i, nblks_lostfound, blk;
#endif
/*
* Initialize the inode for the resizefs feature
*/
if (sblock.e2fs.e2fs_rev > E2FS_REV0 &&
(sblock.e2fs.e2fs_features_compat & EXT2F_COMPAT_RESIZE) != 0)
init_resizeino(tv);
/*
* Initialize the node
*/
#ifdef LOSTDIR
/*
* Create the lost+found directory
*/
if (sblock.e2fs.e2fs_rev > E2FS_REV0 &&
sblock.e2fs.e2fs_features_incompat & EXT2F_INCOMPAT_FTYPE) {
lost_found_dir[0].e2d_type = EXT2_FT_DIR;
lost_found_dir[1].e2d_type = EXT2_FT_DIR;
}
(void)makedir(lost_found_dir, __arraycount(lost_found_dir));
/* prepare a bit large directory for preserved files */
nblks_lostfound = EXT2_LOSTFOUNDSIZE / sblock.e2fs_bsize;
/* ...but only with direct blocks */
if (nblks_lostfound > NDADDR)
nblks_lostfound = NDADDR;
memset(&node, 0, sizeof(node));
node.e2di_mode = EXT2_IFDIR | EXT2_LOSTFOUNDUMASK;
node.e2di_uid = geteuid();
node.e2di_size = sblock.e2fs_bsize * nblks_lostfound;
node.e2di_atime = tv->tv_sec;
node.e2di_ctime = tv->tv_sec;
node.e2di_mtime = tv->tv_sec;
node.e2di_gid = getegid();
node.e2di_nlink = PREDEFDIR;
/* e2di_nblock is a number of disk block, not ext2fs block */
node.e2di_nblock = fsbtodb(&sblock, nblks_lostfound);
node.e2di_blocks[0] = alloc(sblock.e2fs_bsize, node.e2di_mode);
if (node.e2di_blocks[0] == 0) {
printf("%s: can't allocate block for lost+found\n", __func__);
return 0;
}
for (i = 1; i < nblks_lostfound; i++) {
blk = alloc(sblock.e2fs_bsize, 0);
if (blk == 0) {
printf("%s: can't allocate blocks for lost+found\n",
__func__);
return 0;
}
node.e2di_blocks[i] = blk;
}
wtfs(fsbtodb(&sblock, node.e2di_blocks[0]), sblock.e2fs_bsize, buf);
pad_dir.e2d_reclen = sblock.e2fs_bsize;
for (i = 1; i < nblks_lostfound; i++) {
memset(buf, 0, sblock.e2fs_bsize);
copy_dir(&pad_dir, (struct ext2fs_direct *)buf);
wtfs(fsbtodb(&sblock, node.e2di_blocks[i]), sblock.e2fs_bsize,
buf);
}
iput(&node, EXT2_LOSTFOUNDINO);
#endif
/*
* create the root directory
*/
memset(&node, 0, sizeof(node));
if (sblock.e2fs.e2fs_rev > E2FS_REV0 &&
sblock.e2fs.e2fs_features_incompat & EXT2F_INCOMPAT_FTYPE) {
root_dir[0].e2d_type = EXT2_FT_DIR;
root_dir[1].e2d_type = EXT2_FT_DIR;
#ifdef LOSTDIR
root_dir[2].e2d_type = EXT2_FT_DIR;
#endif
}
node.e2di_mode = EXT2_IFDIR | EXT2_UMASK;
node.e2di_uid = geteuid();
node.e2di_size = makedir(root_dir, __arraycount(root_dir));
node.e2di_atime = tv->tv_sec;
node.e2di_ctime = tv->tv_sec;
node.e2di_mtime = tv->tv_sec;
node.e2di_gid = getegid();
node.e2di_nlink = PREDEFROOTDIR;
/* e2di_nblock is a number of disk block, not ext2fs block */
node.e2di_nblock = fsbtodb(&sblock, 1);
node.e2di_blocks[0] = alloc(node.e2di_size, node.e2di_mode);
if (node.e2di_blocks[0] == 0) {
printf("%s: can't allocate block for root dir\n", __func__);
return 0;
}
wtfs(fsbtodb(&sblock, node.e2di_blocks[0]), sblock.e2fs_bsize, buf);
iput(&node, EXT2_ROOTINO);
return 1;
}
/*
* Construct a set of directory entries in "buf".
* return size of directory.
*/
int
makedir(struct ext2fs_direct *protodir, int entries)
{
uint8_t *cp;
uint i, spcleft;
uint dirblksiz;
dirblksiz = sblock.e2fs_bsize;
memset(buf, 0, dirblksiz);
spcleft = dirblksiz;
for (cp = buf, i = 0; i < entries - 1; i++) {
protodir[i].e2d_reclen = EXT2FS_DIRSIZ(protodir[i].e2d_namlen);
copy_dir(&protodir[i], (struct ext2fs_direct *)cp);
cp += protodir[i].e2d_reclen;
spcleft -= protodir[i].e2d_reclen;
}
protodir[i].e2d_reclen = spcleft;
copy_dir(&protodir[i], (struct ext2fs_direct *)cp);
return dirblksiz;
}
/*
* Copy a direntry to a buffer, in fs byte order
*/
static void
copy_dir(struct ext2fs_direct *dir, struct ext2fs_direct *dbuf)
{
memcpy(dbuf, dir, EXT2FS_DIRSIZ(dir->e2d_namlen));
dbuf->e2d_ino = h2fs32(dir->e2d_ino);
dbuf->e2d_reclen = h2fs16(dir->e2d_reclen);
}
/*
* void init_resizeino(const struct timeval *tv);
*
* Initialize the EXT2_RESEIZE_INO inode to prereserve
* reserved group descriptor blocks for future growth of this ext2fs.
*/
void
init_resizeino(const struct timeval *tv)
{
struct ext2fs_dinode node;
uint64_t isize;
uint32_t *dindir_block, *reserved_gdb;
uint nblock, i, cylno, n;
memset(&node, 0, sizeof(node));
/*
* Note this function only prepares required structures for
* future resize. It's a quite different work to implement
* a utility like resize_ext2fs(8) which handles actual
* resize ops even on offline.
*
* Anyway, I'm not sure if there is any documentation about
* this resize ext2fs feature and related data structures,
* and I've written this function based on things what I see
* on some existing implementation and real file system data
* created by existing tools. To be honest, they are not
* so easy to read, so I will try to implement it here without
* any dumb optimization for people who would eventually
* work on "yet another wheel" like resize_ext2fs(8).
*/
/*
* I'm not sure what type is appropriate for this inode.
* The release notes of e2fsprogs says they changed e2fsck to allow
* IFREG for RESIZEINO since a certain resize tool used it. Hmm.
*/
node.e2di_mode = EXT2_IFREG | EXT2_RESIZEINOUMASK;
node.e2di_uid = geteuid();
node.e2di_atime = tv->tv_sec;
node.e2di_ctime = tv->tv_sec;
node.e2di_mtime = tv->tv_sec;
node.e2di_gid = getegid();
node.e2di_nlink = 1;
/*
* To preserve the reserved group descriptor blocks,
* EXT2_RESIZEINO uses only double indirect reference
* blocks in its inode entries.
*
* All entries for direct, single indirect and triple
* indirect references are left zero'ed. Maybe it's safe
* because no write operation will happen with this inode.
*
* We have to allocate a block for the first level double
* indirect reference block. Indexes of inode entries in
* this first level dindirect block are corresponding to
* indexes of group descriptors including both used (e2fs_ngdb)
* and reserved (e2fs_reserved_ngdb) group descriptor blocks.
*
* Inode entries of indexes for used (e2fs_ngdb) descriptors are
* left zero'ed. Entries for reserved (e2fs_reserved_ngdb) ones
* have block numbers of actual reserved group descriptors
* allocated at block group zero. This means e2fs_reserved_ngdb
* blocks are reserved as the second level dindirect reference
* blocks, and they acutually contain block numbers of indirect
* references. It may be safe since they don't have to keep any
* data yet.
*
* Each these second dindirect blocks (i.e. reserved group
* descriptor blocks in the first block group) should have
* block numbers of its backups in all other block groups.
* I.e. reserved_ngdb[0] block in block group 0 contains block
* numbers of resreved_ngdb[0] from group 1 through (e2fs_ncg - 1).
* The number of backups can be determined by the
* EXT2_ROCOMPAT_SPARSESUPER feature and cg_has_sb() macro
* as done in the above initcg() function.
*/
/* set e2di_size which occupies whole blocks through DINDIR blocks */
isize = (uint64_t)sblock.e2fs_bsize * NDADDR +
(uint64_t)sblock.e2fs_bsize * NINDIR(&sblock) +
(uint64_t)sblock.e2fs_bsize * NINDIR(&sblock) * NINDIR(&sblock);
if (isize > UINT32_MAX &&
(sblock.e2fs.e2fs_features_rocompat &
EXT2F_ROCOMPAT_LARGEFILE) == 0) {
/* XXX should enable it here and update all backups? */
errx(EXIT_FAILURE, "%s: large_file rocompat feature is "
"required to enable resize feature for this filesystem\n",
__func__);
}
/* upper 32bit is stored into e2di_dacl on REV1 feature */
node.e2di_size = isize & UINT32_MAX;
node.e2di_dacl = isize >> 32;
#define SINGLE 0 /* index of single indirect block */
#define DOUBLE 1 /* index of double indirect block */
#define TRIPLE 2 /* index of triple indirect block */
/* zero out entries for direct references */
for (i = 0; i < NDADDR; i++)
node.e2di_blocks[i] = 0;
/* also zero out entries for single and triple indirect references */
node.e2di_blocks[NDADDR + SINGLE] = 0;
node.e2di_blocks[NDADDR + TRIPLE] = 0;
/* allocate a block for the first level double indirect reference */
node.e2di_blocks[NDADDR + DOUBLE] =
alloc(sblock.e2fs_bsize, node.e2di_mode);
if (node.e2di_blocks[NDADDR + DOUBLE] == 0)
errx(EXIT_FAILURE, "%s: Can't allocate a dindirect block",
__func__);
/* account this first block */
nblock = fsbtodb(&sblock, 1);
/* allocate buffer to set data in the dindirect block */
dindir_block = malloc(sblock.e2fs_bsize);
if (dindir_block == NULL)
errx(EXIT_FAILURE,
"%s: Can't allocate buffer for a dindirect block",
__func__);
/* allocate buffer to set data in the group descriptor blocks */
reserved_gdb = malloc(sblock.e2fs_bsize);
if (reserved_gdb == NULL)
errx(EXIT_FAILURE,
"%s: Can't allocate buffer for group descriptor blocks",
__func__);
/*
* Setup block entries in the first level dindirect blocks
*/
for (i = 0; i < sblock.e2fs_ngdb; i++) {
/* no need to handle used group descriptor blocks */
dindir_block[i] = 0;
}
for (; i < sblock.e2fs_ngdb + sblock.e2fs.e2fs_reserved_ngdb; i++) {
/*
* point reserved group descriptor block in the first
* (i.e. master) block group
*
* XXX: e2fsprogs seem to use "(i % NINDIR(&sblock))" here
* to store maximum NINDIR(&sblock) reserved gdbs.
* I'm not sure what will be done on future filesystem
* shrink in that case on their way.
*/
if (i >= NINDIR(&sblock))
errx(EXIT_FAILURE, "%s: too many reserved "
"group descriptors (%u) for resize inode",
__func__, sblock.e2fs.e2fs_reserved_ngdb);
dindir_block[i] =
h2fs32(cgbase(&sblock, 0) + NBLOCK_SUPERBLOCK + i);
/*
* Setup block entries in the second dindirect blocks
* (which are primary reserved group descriptor blocks)
* to point their backups.
*/
for (n = 0, cylno = 1; cylno < sblock.e2fs_ncg; cylno++) {
/* skip block groups without backup */
if ((sblock.e2fs.e2fs_features_rocompat &
EXT2F_ROCOMPAT_SPARSESUPER) != 0 &&
cg_has_sb(cylno) == 0)
continue;
if (n >= NINDIR(&sblock))
errx(EXIT_FAILURE, "%s: too many block groups "
"for the resize feature", __func__);
/*
* These blocks are already reserved in
* initcg() so no need to use alloc() here.
*/
reserved_gdb[n++] = h2fs32(cgbase(&sblock, cylno) +
NBLOCK_SUPERBLOCK + i);
nblock += fsbtodb(&sblock, 1);
}
for (; n < NINDIR(&sblock); n++)
reserved_gdb[n] = 0;
/* write group descriptor block as the second dindirect refs */
wtfs(fsbtodb(&sblock, fs2h32(dindir_block[i])),
sblock.e2fs_bsize, reserved_gdb);
nblock += fsbtodb(&sblock, 1);
}
for (; i < NINDIR(&sblock); i++) {
/* leave trailing entries unallocated */
dindir_block[i] = 0;
}
free(reserved_gdb);
/* finally write the first level dindirect block */
wtfs(fsbtodb(&sblock, node.e2di_blocks[NDADDR + DOUBLE]),
sblock.e2fs_bsize, dindir_block);
free(dindir_block);
node.e2di_nblock = nblock;
iput(&node, EXT2_RESIZEINO);
}
/*
* uint32_t alloc(uint32_t size, uint16_t mode)
*
* Allocate a block (from cylinder group 0)
* Reference: src/sys/ufs/ext2fs/ext2fs_alloc.c:ext2fs_alloccg()
*/
uint32_t
alloc(uint32_t size, uint16_t mode)
{
uint32_t loc, bno;
uint8_t *bbp;
uint len, map, i;
if (gd[0].ext2bgd_nbfree == 0)
return 0;
if (size > sblock.e2fs_bsize)
return 0;
bbp = malloc(sblock.e2fs_bsize);
if (bbp == NULL)
return 0;
rdfs(fsbtodb(&sblock, gd[0].ext2bgd_b_bitmap), sblock.e2fs_bsize, bbp);
/* XXX: kernel uses e2fs_fpg here */
len = sblock.e2fs.e2fs_bpg / NBBY;
#if 0 /* no need block allocation for root or lost+found dir */
for (loc = 0; loc < len; loc++) {
if (bbp[loc] == 0) {
bno = loc * NBBY;
goto gotit;
}
}
#endif
loc = skpc(~0U, len, bbp);
if (loc == 0)
return 0;
loc = len - loc;
map = bbp[loc];
bno = loc * NBBY;
for (i = 0; i < NBBY; i++, bno++) {
if ((map & (1 << i)) == 0)
goto gotit;
}
return 0;
gotit:
if (isset(bbp, bno))
errx(EXIT_FAILURE, "%s: inconsistent bitmap\n", __func__);
setbit(bbp, bno);
wtfs(fsbtodb(&sblock, gd[0].ext2bgd_b_bitmap), sblock.e2fs_bsize, bbp);
free(bbp);
/* XXX: modified group descriptors won't be written into backups */
gd[0].ext2bgd_nbfree--;
if ((mode & EXT2_IFDIR) != 0)
gd[0].ext2bgd_ndirs++;
sblock.e2fs.e2fs_fbcount--;
return sblock.e2fs.e2fs_first_dblock + bno;
}
/*
* void iput(struct ext2fs_dinode *ip, ino_t ino)
*
* Put an inode entry into the corresponding table.
*/
static void
iput(struct ext2fs_dinode *ip, ino_t ino)
{
daddr_t d;
uint c, i;
struct ext2fs_dinode *dp;
uint8_t *bp;
bp = malloc(sblock.e2fs_bsize);
if (bp == NULL)
errx(EXIT_FAILURE, "%s: can't allocate buffer for inode\n",
__func__);
/*
* Reserved inodes are allocated and accounted in initcg()
* so skip checks of the bitmap and allocation for them.
*/
if (ino >= EXT2_FIRSTINO) {
c = ino_to_cg(&sblock, ino);
/* sanity check */
if (gd[c].ext2bgd_nifree == 0)
errx(EXIT_FAILURE,
"%s: no free inode %" PRIu64 " in block group %u\n",
__func__, (uint64_t)ino, c);
/* update inode bitmap */
rdfs(fsbtodb(&sblock, gd[0].ext2bgd_i_bitmap),
sblock.e2fs_bsize, bp);
/* more sanity */
if (isset(bp, EXT2_INO_INDEX(ino)))
errx(EXIT_FAILURE, "%s: inode %" PRIu64
" already in use\n", __func__, (uint64_t)ino);
setbit(bp, EXT2_INO_INDEX(ino));
wtfs(fsbtodb(&sblock, gd[0].ext2bgd_i_bitmap),
sblock.e2fs_bsize, bp);
gd[c].ext2bgd_nifree--;
sblock.e2fs.e2fs_ficount--;
}
if (ino >= sblock.e2fs.e2fs_ipg * sblock.e2fs_ncg)
errx(EXIT_FAILURE, "%s: inode value out of range (%" PRIu64
").\n", __func__, (uint64_t)ino);
/* update an inode entry in the table */
d = fsbtodb(&sblock, ino_to_fsba(&sblock, ino));
rdfs(d, sblock.e2fs_bsize, bp);
dp = (struct ext2fs_dinode *)bp;
dp += ino_to_fsbo(&sblock, ino);
e2fs_isave(ip, dp);
/* e2fs_i_bswap() doesn't swap e2di_blocks addrs */
if ((ip->e2di_mode & EXT2_IFMT) != EXT2_IFLNK) {
for (i = 0; i < NDADDR + NIADDR; i++)
dp->e2di_blocks[i] = h2fs32(ip->e2di_blocks[i]);
}
/* h2fs32() just for consistency */
dp->e2di_gen = h2fs32(arc4random());
wtfs(d, sblock.e2fs_bsize, bp);
free(bp);
}
/*
* Read a block from the file system
*/
void
rdfs(daddr_t bno, int size, void *bf)
{
int n;
off_t offset;
offset = bno;
n = pread(fsi, bf, size, offset * sectorsize);
if (n != size)
err(EXIT_FAILURE, "%s: read error for sector %" PRId64,
__func__, (int64_t)bno);
}
/*
* Write a block to the file system
*/
void
wtfs(daddr_t bno, int size, void *bf)
{
int n;
off_t offset;
if (Nflag)
return;
offset = bno;
n = pwrite(fso, bf, size, offset * sectorsize);
if (n != size)
err(EXIT_FAILURE, "%s: write error for sector %" PRId64,
__func__, (int64_t)bno);
}
int
ilog2(uint val)
{
if (val == 0 || !powerof2(val))
errx(EXIT_FAILURE, "%s: %u is not a power of 2\n",
__func__, val);
return ffs(val) - 1;
}
/*
* int skpc(int mask, size_t size, uint8_t *cp)
*
* Locate an unsigned character of value mask inside cp[].
* (from src/sys/lib/libkern/skpc.c)
*/
int
skpc(int mask, size_t size, uint8_t *cp)
{
uint8_t *end;
end = &cp[size];
while (cp < end && *cp == (uint8_t)mask)
cp++;
return end - cp;
}