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freebsd-dev/sys/gnu/fs/ext2fs/ext2_vfsops.c
Craig Rodrigues bdb7d194d0 In ext2_mountfs(), check that the superblock size, SBSIZE, 
is aligned with the sectorsize value returned by GEOM, before
doing a bread() of the superblock.
This eliminates a panic when trying the following on an empty CD-ROM drive:
mount_ext2fs /dev/acd0 /mnt

Reviewed by:	phk
2005-09-10 21:30:49 +00:00

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31 KiB
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/*-
* modified for EXT2FS support in Lites 1.1
*
* Aug 1995, Godmar Back (gback@cs.utah.edu)
* University of Utah, Department of Computer Science
*/
/*-
* Copyright (c) 1989, 1991, 1993, 1994
* 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.
* 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.
*
* @(#)ffs_vfsops.c 8.8 (Berkeley) 4/18/94
* $FreeBSD$
*/
/*-
* COPYRIGHT.INFO says this has some GPL'd code from ext2_super.c in it
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/namei.h>
#include <sys/proc.h>
#include <sys/kernel.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/bio.h>
#include <sys/buf.h>
#include <sys/conf.h>
#include <sys/fcntl.h>
#include <sys/malloc.h>
#include <sys/stat.h>
#include <sys/mutex.h>
#include <geom/geom.h>
#include <geom/geom_vfs.h>
#include <gnu/fs/ext2fs/ext2_mount.h>
#include <gnu/fs/ext2fs/inode.h>
#include <gnu/fs/ext2fs/fs.h>
#include <gnu/fs/ext2fs/ext2_extern.h>
#include <gnu/fs/ext2fs/ext2_fs.h>
#include <gnu/fs/ext2fs/ext2_fs_sb.h>
static int ext2_flushfiles(struct mount *mp, int flags, struct thread *td);
static int ext2_mountfs(struct vnode *, struct mount *, struct thread *);
static int ext2_reload(struct mount *mp, struct thread *td);
static int ext2_sbupdate(struct ext2mount *, int);
static vfs_unmount_t ext2_unmount;
static vfs_root_t ext2_root;
static vfs_statfs_t ext2_statfs;
static vfs_sync_t ext2_sync;
static vfs_vget_t ext2_vget;
static vfs_fhtovp_t ext2_fhtovp;
static vfs_vptofh_t ext2_vptofh;
static vfs_mount_t ext2_mount;
MALLOC_DEFINE(M_EXT2NODE, "EXT2 node", "EXT2 vnode private part");
static MALLOC_DEFINE(M_EXT2MNT, "EXT2 mount", "EXT2 mount structure");
static struct vfsops ext2fs_vfsops = {
.vfs_fhtovp = ext2_fhtovp,
.vfs_mount = ext2_mount,
.vfs_root = ext2_root, /* root inode via vget */
.vfs_statfs = ext2_statfs,
.vfs_sync = ext2_sync,
.vfs_unmount = ext2_unmount,
.vfs_vget = ext2_vget,
.vfs_vptofh = ext2_vptofh,
};
VFS_SET(ext2fs_vfsops, ext2fs, 0);
#define bsd_malloc malloc
#define bsd_free free
static int ext2_check_sb_compat(struct ext2_super_block *es, struct cdev *dev,
int ronly);
static int compute_sb_data(struct vnode * devvp,
struct ext2_super_block * es, struct ext2_sb_info * fs);
static const char *ext2_opts[] = { "from", "export" };
/*
* VFS Operations.
*
* mount system call
*/
static int
ext2_mount(mp, td)
struct mount *mp;
struct thread *td;
{
struct export_args *export;
struct vfsoptlist *opts;
struct vnode *devvp;
struct ext2mount *ump = 0;
struct ext2_sb_info *fs;
char *path, *fspec;
int error, flags, len;
mode_t accessmode;
struct nameidata nd, *ndp = &nd;
opts = mp->mnt_optnew;
if (vfs_filteropt(opts, ext2_opts))
return (EINVAL);
vfs_getopt(opts, "fspath", (void **)&path, NULL);
/* Double-check the length of path.. */
if (strlen(path) >= MAXMNTLEN - 1)
return (ENAMETOOLONG);
fspec = NULL;
error = vfs_getopt(opts, "from", (void **)&fspec, &len);
if (!error && fspec[len - 1] != '\0')
return (EINVAL);
/*
* If updating, check whether changing from read-only to
* read/write; if there is no device name, that's all we do.
*/
if (mp->mnt_flag & MNT_UPDATE) {
ump = VFSTOEXT2(mp);
fs = ump->um_e2fs;
error = 0;
if (fs->s_rd_only == 0 &&
vfs_flagopt(opts, "ro", NULL, 0)) {
error = VFS_SYNC(mp, MNT_WAIT, td);
if (error)
return (error);
flags = WRITECLOSE;
if (mp->mnt_flag & MNT_FORCE)
flags |= FORCECLOSE;
if (vfs_busy(mp, LK_NOWAIT, 0, td))
return (EBUSY);
error = ext2_flushfiles(mp, flags, td);
vfs_unbusy(mp, td);
if (!error && fs->s_wasvalid) {
fs->s_es->s_state |= EXT2_VALID_FS;
ext2_sbupdate(ump, MNT_WAIT);
}
fs->s_rd_only = 1;
vfs_flagopt(opts, "ro", &mp->mnt_flag, MNT_RDONLY);
DROP_GIANT();
g_topology_lock();
g_access(ump->um_cp, 0, -1, 0);
g_topology_unlock();
PICKUP_GIANT();
}
if (!error && (mp->mnt_flag & MNT_RELOAD))
error = ext2_reload(mp, td);
if (error)
return (error);
devvp = ump->um_devvp;
if (fs->s_rd_only && !vfs_flagopt(opts, "ro", NULL, 0)) {
if (ext2_check_sb_compat(fs->s_es, devvp->v_rdev, 0))
return (EPERM);
/*
* If upgrade to read-write by non-root, then verify
* that user has necessary permissions on the device.
*/
if (suser(td)) {
vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, td);
if ((error = VOP_ACCESS(devvp, VREAD | VWRITE,
td->td_ucred, td)) != 0) {
VOP_UNLOCK(devvp, 0, td);
return (error);
}
VOP_UNLOCK(devvp, 0, td);
}
DROP_GIANT();
g_topology_lock();
error = g_access(ump->um_cp, 0, 1, 0);
g_topology_unlock();
PICKUP_GIANT();
if (error)
return (error);
if ((fs->s_es->s_state & EXT2_VALID_FS) == 0 ||
(fs->s_es->s_state & EXT2_ERROR_FS)) {
if (mp->mnt_flag & MNT_FORCE) {
printf(
"WARNING: %s was not properly dismounted\n",
fs->fs_fsmnt);
} else {
printf(
"WARNING: R/W mount of %s denied. Filesystem is not clean - run fsck\n",
fs->fs_fsmnt);
return (EPERM);
}
}
fs->s_es->s_state &= ~EXT2_VALID_FS;
ext2_sbupdate(ump, MNT_WAIT);
fs->s_rd_only = 0;
mp->mnt_flag &= ~MNT_RDONLY;
}
if (fspec == NULL) {
error = vfs_getopt(opts, "export", (void **)&export,
&len);
if (error || len != sizeof(struct export_args))
return (EINVAL);
/* Process export requests. */
return (vfs_export(mp, export));
}
}
/*
* Not an update, or updating the name: look up the name
* and verify that it refers to a sensible disk device.
*/
if (fspec == NULL)
return (EINVAL);
NDINIT(ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, fspec, td);
if ((error = namei(ndp)) != 0)
return (error);
NDFREE(ndp, NDF_ONLY_PNBUF);
devvp = ndp->ni_vp;
if (!vn_isdisk(devvp, &error)) {
vput(devvp);
return (error);
}
/*
* If mount by non-root, then verify that user has necessary
* permissions on the device.
*/
if (suser(td)) {
accessmode = VREAD;
if ((mp->mnt_flag & MNT_RDONLY) == 0)
accessmode |= VWRITE;
if ((error = VOP_ACCESS(devvp, accessmode, td->td_ucred, td)) != 0) {
vput(devvp);
return (error);
}
}
if ((mp->mnt_flag & MNT_UPDATE) == 0) {
error = ext2_mountfs(devvp, mp, td);
} else {
if (devvp != ump->um_devvp) {
vput(devvp);
return (EINVAL); /* needs translation */
} else
vput(devvp);
}
if (error) {
vrele(devvp);
return (error);
}
ump = VFSTOEXT2(mp);
fs = ump->um_e2fs;
/*
* Note that this strncpy() is ok because of a check at the start
* of ext2_mount().
*/
strncpy(fs->fs_fsmnt, path, MAXMNTLEN);
fs->fs_fsmnt[MAXMNTLEN - 1] = '\0';
vfs_mountedfrom(mp, fspec);
return (0);
}
/*
* checks that the data in the descriptor blocks make sense
* this is taken from ext2/super.c
*/
static int ext2_check_descriptors (struct ext2_sb_info * sb)
{
int i;
int desc_block = 0;
unsigned long block = sb->s_es->s_first_data_block;
struct ext2_group_desc * gdp = NULL;
/* ext2_debug ("Checking group descriptors"); */
for (i = 0; i < sb->s_groups_count; i++)
{
/* examine next descriptor block */
if ((i % EXT2_DESC_PER_BLOCK(sb)) == 0)
gdp = (struct ext2_group_desc *)
sb->s_group_desc[desc_block++]->b_data;
if (gdp->bg_block_bitmap < block ||
gdp->bg_block_bitmap >= block + EXT2_BLOCKS_PER_GROUP(sb))
{
printf ("ext2_check_descriptors: "
"Block bitmap for group %d"
" not in group (block %lu)!\n",
i, (unsigned long) gdp->bg_block_bitmap);
return 0;
}
if (gdp->bg_inode_bitmap < block ||
gdp->bg_inode_bitmap >= block + EXT2_BLOCKS_PER_GROUP(sb))
{
printf ("ext2_check_descriptors: "
"Inode bitmap for group %d"
" not in group (block %lu)!\n",
i, (unsigned long) gdp->bg_inode_bitmap);
return 0;
}
if (gdp->bg_inode_table < block ||
gdp->bg_inode_table + sb->s_itb_per_group >=
block + EXT2_BLOCKS_PER_GROUP(sb))
{
printf ("ext2_check_descriptors: "
"Inode table for group %d"
" not in group (block %lu)!\n",
i, (unsigned long) gdp->bg_inode_table);
return 0;
}
block += EXT2_BLOCKS_PER_GROUP(sb);
gdp++;
}
return 1;
}
static int
ext2_check_sb_compat(es, dev, ronly)
struct ext2_super_block *es;
struct cdev *dev;
int ronly;
{
if (es->s_magic != EXT2_SUPER_MAGIC) {
printf("ext2fs: %s: wrong magic number %#x (expected %#x)\n",
devtoname(dev), es->s_magic, EXT2_SUPER_MAGIC);
return (1);
}
if (es->s_rev_level > EXT2_GOOD_OLD_REV) {
if (es->s_feature_incompat & ~EXT2_FEATURE_INCOMPAT_SUPP) {
printf(
"WARNING: mount of %s denied due to unsupported optional features\n",
devtoname(dev));
return (1);
}
if (!ronly &&
(es->s_feature_ro_compat & ~EXT2_FEATURE_RO_COMPAT_SUPP)) {
printf(
"WARNING: R/W mount of %s denied due to unsupported optional features\n",
devtoname(dev));
return (1);
}
}
return (0);
}
/*
* this computes the fields of the ext2_sb_info structure from the
* data in the ext2_super_block structure read in
*/
static int compute_sb_data(devvp, es, fs)
struct vnode * devvp;
struct ext2_super_block * es;
struct ext2_sb_info * fs;
{
int db_count, error;
int i, j;
int logic_sb_block = 1; /* XXX for now */
#if 1
#define V(v)
#else
#define V(v) printf(#v"= %d\n", fs->v);
#endif
fs->s_blocksize = EXT2_MIN_BLOCK_SIZE << es->s_log_block_size;
V(s_blocksize)
fs->s_bshift = EXT2_MIN_BLOCK_LOG_SIZE + es->s_log_block_size;
V(s_bshift)
fs->s_fsbtodb = es->s_log_block_size + 1;
V(s_fsbtodb)
fs->s_qbmask = fs->s_blocksize - 1;
V(s_bmask)
fs->s_blocksize_bits = EXT2_BLOCK_SIZE_BITS(es);
V(s_blocksize_bits)
fs->s_frag_size = EXT2_MIN_FRAG_SIZE << es->s_log_frag_size;
V(s_frag_size)
if (fs->s_frag_size)
fs->s_frags_per_block = fs->s_blocksize / fs->s_frag_size;
V(s_frags_per_block)
fs->s_blocks_per_group = es->s_blocks_per_group;
V(s_blocks_per_group)
fs->s_frags_per_group = es->s_frags_per_group;
V(s_frags_per_group)
fs->s_inodes_per_group = es->s_inodes_per_group;
V(s_inodes_per_group)
fs->s_inodes_per_block = fs->s_blocksize / EXT2_INODE_SIZE;
V(s_inodes_per_block)
fs->s_itb_per_group = fs->s_inodes_per_group /fs->s_inodes_per_block;
V(s_itb_per_group)
fs->s_desc_per_block = fs->s_blocksize / sizeof (struct ext2_group_desc);
V(s_desc_per_block)
/* s_resuid / s_resgid ? */
fs->s_groups_count = (es->s_blocks_count -
es->s_first_data_block +
EXT2_BLOCKS_PER_GROUP(fs) - 1) /
EXT2_BLOCKS_PER_GROUP(fs);
V(s_groups_count)
db_count = (fs->s_groups_count + EXT2_DESC_PER_BLOCK(fs) - 1) /
EXT2_DESC_PER_BLOCK(fs);
fs->s_db_per_group = db_count;
V(s_db_per_group)
fs->s_group_desc = bsd_malloc(db_count * sizeof (struct buf *),
M_EXT2MNT, M_WAITOK);
/* adjust logic_sb_block */
if(fs->s_blocksize > SBSIZE)
/* Godmar thinks: if the blocksize is greater than 1024, then
the superblock is logically part of block zero.
*/
logic_sb_block = 0;
for (i = 0; i < db_count; i++) {
error = bread(devvp , fsbtodb(fs, logic_sb_block + i + 1),
fs->s_blocksize, NOCRED, &fs->s_group_desc[i]);
if(error) {
for (j = 0; j < i; j++)
brelse(fs->s_group_desc[j]);
bsd_free(fs->s_group_desc, M_EXT2MNT);
printf("EXT2-fs: unable to read group descriptors (%d)\n", error);
return EIO;
}
LCK_BUF(fs->s_group_desc[i])
}
if(!ext2_check_descriptors(fs)) {
for (j = 0; j < db_count; j++)
ULCK_BUF(fs->s_group_desc[j])
bsd_free(fs->s_group_desc, M_EXT2MNT);
printf("EXT2-fs: (ext2_check_descriptors failure) "
"unable to read group descriptors\n");
return EIO;
}
for (i = 0; i < EXT2_MAX_GROUP_LOADED; i++) {
fs->s_inode_bitmap_number[i] = 0;
fs->s_inode_bitmap[i] = NULL;
fs->s_block_bitmap_number[i] = 0;
fs->s_block_bitmap[i] = NULL;
}
fs->s_loaded_inode_bitmaps = 0;
fs->s_loaded_block_bitmaps = 0;
if (es->s_rev_level == EXT2_GOOD_OLD_REV || (es->s_feature_ro_compat &
EXT2_FEATURE_RO_COMPAT_LARGE_FILE) == 0)
fs->fs_maxfilesize = 0x7fffffff;
else
fs->fs_maxfilesize = 0x7fffffffffffffff;
return 0;
}
/*
* Reload all incore data for a filesystem (used after running fsck on
* the root filesystem and finding things to fix). The filesystem must
* be mounted read-only.
*
* Things to do to update the mount:
* 1) invalidate all cached meta-data.
* 2) re-read superblock from disk.
* 3) re-read summary information from disk.
* 4) invalidate all inactive vnodes.
* 5) invalidate all cached file data.
* 6) re-read inode data for all active vnodes.
*/
static int
ext2_reload(struct mount *mp, struct thread *td)
{
struct vnode *vp, *nvp, *devvp;
struct inode *ip;
struct buf *bp;
struct ext2_super_block * es;
struct ext2_sb_info *fs;
int error;
if ((mp->mnt_flag & MNT_RDONLY) == 0)
return (EINVAL);
/*
* Step 1: invalidate all cached meta-data.
*/
devvp = VFSTOEXT2(mp)->um_devvp;
vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, td);
if (vinvalbuf(devvp, 0, td, 0, 0) != 0)
panic("ext2_reload: dirty1");
VOP_UNLOCK(devvp, 0, td);
/*
* Step 2: re-read superblock from disk.
* constants have been adjusted for ext2
*/
if ((error = bread(devvp, SBLOCK, SBSIZE, NOCRED, &bp)) != 0)
return (error);
es = (struct ext2_super_block *)bp->b_data;
if (ext2_check_sb_compat(es, devvp->v_rdev, 0) != 0) {
brelse(bp);
return (EIO); /* XXX needs translation */
}
fs = VFSTOEXT2(mp)->um_e2fs;
bcopy(bp->b_data, fs->s_es, sizeof(struct ext2_super_block));
if((error = compute_sb_data(devvp, es, fs)) != 0) {
brelse(bp);
return error;
}
#ifdef UNKLAR
if (fs->fs_sbsize < SBSIZE)
bp->b_flags |= B_INVAL;
#endif
brelse(bp);
loop:
MNT_ILOCK(mp);
MNT_VNODE_FOREACH(vp, mp, nvp) {
VI_LOCK(vp);
if (vp->v_iflag & VI_DOOMED) {
VI_UNLOCK(vp);
continue;
}
MNT_IUNLOCK(mp);
/*
* Step 4: invalidate all cached file data.
*/
if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK, td)) {
goto loop;
}
if (vinvalbuf(vp, 0, td, 0, 0))
panic("ext2_reload: dirty2");
/*
* Step 5: re-read inode data for all active vnodes.
*/
ip = VTOI(vp);
error =
bread(devvp, fsbtodb(fs, ino_to_fsba(fs, ip->i_number)),
(int)fs->s_blocksize, NOCRED, &bp);
if (error) {
VOP_UNLOCK(vp, 0, td);
vrele(vp);
return (error);
}
ext2_ei2i((struct ext2_inode *) ((char *)bp->b_data +
EXT2_INODE_SIZE * ino_to_fsbo(fs, ip->i_number)), ip);
brelse(bp);
VOP_UNLOCK(vp, 0, td);
vrele(vp);
MNT_ILOCK(mp);
}
MNT_IUNLOCK(mp);
return (0);
}
/*
* Common code for mount and mountroot
*/
static int
ext2_mountfs(devvp, mp, td)
struct vnode *devvp;
struct mount *mp;
struct thread *td;
{
struct ext2mount *ump;
struct buf *bp;
struct ext2_sb_info *fs;
struct ext2_super_block * es;
struct cdev *dev = devvp->v_rdev;
struct g_consumer *cp;
struct bufobj *bo;
int error;
int ronly;
ronly = vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0);
/* XXX: use VOP_ACESS to check FS perms */
DROP_GIANT();
g_topology_lock();
error = g_vfs_open(devvp, &cp, "ext2fs", ronly ? 0 : 1);
g_topology_unlock();
PICKUP_GIANT();
VOP_UNLOCK(devvp, 0, td);
if (error)
return (error);
/* XXX: should we check for some sectorsize or 512 instead? */
if (((SBSIZE % cp->provider->sectorsize) != 0) ||
(SBSIZE < cp->provider->sectorsize)) {
DROP_GIANT();
g_topology_lock();
g_vfs_close(cp, td);
g_topology_unlock();
PICKUP_GIANT();
return (EINVAL);
}
bo = &devvp->v_bufobj;
bo->bo_private = cp;
bo->bo_ops = g_vfs_bufops;
if (devvp->v_rdev->si_iosize_max != 0)
mp->mnt_iosize_max = devvp->v_rdev->si_iosize_max;
if (mp->mnt_iosize_max > MAXPHYS)
mp->mnt_iosize_max = MAXPHYS;
bp = NULL;
ump = NULL;
if ((error = bread(devvp, SBLOCK, SBSIZE, NOCRED, &bp)) != 0)
goto out;
es = (struct ext2_super_block *)bp->b_data;
if (ext2_check_sb_compat(es, dev, ronly) != 0) {
error = EINVAL; /* XXX needs translation */
goto out;
}
if ((es->s_state & EXT2_VALID_FS) == 0 ||
(es->s_state & EXT2_ERROR_FS)) {
if (ronly || (mp->mnt_flag & MNT_FORCE)) {
printf(
"WARNING: Filesystem was not properly dismounted\n");
} else {
printf(
"WARNING: R/W mount denied. Filesystem is not clean - run fsck\n");
error = EPERM;
goto out;
}
}
ump = bsd_malloc(sizeof *ump, M_EXT2MNT, M_WAITOK);
bzero((caddr_t)ump, sizeof *ump);
/* I don't know whether this is the right strategy. Note that
we dynamically allocate both an ext2_sb_info and an ext2_super_block
while Linux keeps the super block in a locked buffer
*/
ump->um_e2fs = bsd_malloc(sizeof(struct ext2_sb_info),
M_EXT2MNT, M_WAITOK);
ump->um_e2fs->s_es = bsd_malloc(sizeof(struct ext2_super_block),
M_EXT2MNT, M_WAITOK);
bcopy(es, ump->um_e2fs->s_es, (u_int)sizeof(struct ext2_super_block));
if ((error = compute_sb_data(devvp, ump->um_e2fs->s_es, ump->um_e2fs)))
goto out;
/*
* We don't free the group descriptors allocated by compute_sb_data()
* until ext2_unmount(). This is OK since the mount will succeed.
*/
brelse(bp);
bp = NULL;
fs = ump->um_e2fs;
fs->s_rd_only = ronly; /* ronly is set according to mnt_flags */
/* if the fs is not mounted read-only, make sure the super block is
always written back on a sync()
*/
fs->s_wasvalid = fs->s_es->s_state & EXT2_VALID_FS ? 1 : 0;
if (ronly == 0) {
fs->s_dirt = 1; /* mark it modified */
fs->s_es->s_state &= ~EXT2_VALID_FS; /* set fs invalid */
}
mp->mnt_data = (qaddr_t)ump;
mp->mnt_stat.f_fsid.val[0] = dev2udev(dev);
mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum;
mp->mnt_maxsymlinklen = EXT2_MAXSYMLINKLEN;
mp->mnt_flag |= MNT_LOCAL;
ump->um_mountp = mp;
ump->um_dev = dev;
ump->um_devvp = devvp;
ump->um_bo = &devvp->v_bufobj;
ump->um_cp = cp;
/* setting those two parameters allowed us to use
ufs_bmap w/o changse !
*/
ump->um_nindir = EXT2_ADDR_PER_BLOCK(fs);
ump->um_bptrtodb = fs->s_es->s_log_block_size + 1;
ump->um_seqinc = EXT2_FRAGS_PER_BLOCK(fs);
if (ronly == 0)
ext2_sbupdate(ump, MNT_WAIT);
return (0);
out:
if (bp)
brelse(bp);
if (cp != NULL) {
DROP_GIANT();
g_topology_lock();
g_vfs_close(cp, td);
g_topology_unlock();
PICKUP_GIANT();
}
if (ump) {
bsd_free(ump->um_e2fs->s_es, M_EXT2MNT);
bsd_free(ump->um_e2fs, M_EXT2MNT);
bsd_free(ump, M_EXT2MNT);
mp->mnt_data = (qaddr_t)0;
}
return (error);
}
/*
* unmount system call
*/
static int
ext2_unmount(mp, mntflags, td)
struct mount *mp;
int mntflags;
struct thread *td;
{
struct ext2mount *ump;
struct ext2_sb_info *fs;
int error, flags, ronly, i;
flags = 0;
if (mntflags & MNT_FORCE) {
if (mp->mnt_flag & MNT_ROOTFS)
return (EINVAL);
flags |= FORCECLOSE;
}
if ((error = ext2_flushfiles(mp, flags, td)) != 0)
return (error);
ump = VFSTOEXT2(mp);
fs = ump->um_e2fs;
ronly = fs->s_rd_only;
if (ronly == 0) {
if (fs->s_wasvalid)
fs->s_es->s_state |= EXT2_VALID_FS;
ext2_sbupdate(ump, MNT_WAIT);
}
/* release buffers containing group descriptors */
for(i = 0; i < fs->s_db_per_group; i++)
ULCK_BUF(fs->s_group_desc[i])
bsd_free(fs->s_group_desc, M_EXT2MNT);
/* release cached inode/block bitmaps */
for (i = 0; i < EXT2_MAX_GROUP_LOADED; i++)
if (fs->s_inode_bitmap[i])
ULCK_BUF(fs->s_inode_bitmap[i])
for (i = 0; i < EXT2_MAX_GROUP_LOADED; i++)
if (fs->s_block_bitmap[i])
ULCK_BUF(fs->s_block_bitmap[i])
DROP_GIANT();
g_topology_lock();
g_vfs_close(ump->um_cp, td);
g_topology_unlock();
PICKUP_GIANT();
vrele(ump->um_devvp);
bsd_free(fs->s_es, M_EXT2MNT);
bsd_free(fs, M_EXT2MNT);
bsd_free(ump, M_EXT2MNT);
mp->mnt_data = (qaddr_t)0;
mp->mnt_flag &= ~MNT_LOCAL;
return (error);
}
/*
* Flush out all the files in a filesystem.
*/
static int
ext2_flushfiles(mp, flags, td)
struct mount *mp;
int flags;
struct thread *td;
{
int error;
error = vflush(mp, 0, flags, td);
return (error);
}
/*
* Get file system statistics.
* taken from ext2/super.c ext2_statfs
*/
static int
ext2_statfs(mp, sbp, td)
struct mount *mp;
struct statfs *sbp;
struct thread *td;
{
unsigned long overhead;
struct ext2mount *ump;
struct ext2_sb_info *fs;
struct ext2_super_block *es;
int i, nsb;
ump = VFSTOEXT2(mp);
fs = ump->um_e2fs;
es = fs->s_es;
if (es->s_magic != EXT2_SUPER_MAGIC)
panic("ext2_statfs - magic number spoiled");
/*
* Compute the overhead (FS structures)
*/
if (es->s_feature_ro_compat & EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER) {
nsb = 0;
for (i = 0 ; i < fs->s_groups_count; i++)
if (ext2_group_sparse(i))
nsb++;
} else
nsb = fs->s_groups_count;
overhead = es->s_first_data_block +
/* Superblocks and block group descriptors: */
nsb * (1 + fs->s_db_per_group) +
/* Inode bitmap, block bitmap, and inode table: */
fs->s_groups_count * (1 + 1 + fs->s_itb_per_group);
sbp->f_bsize = EXT2_FRAG_SIZE(fs);
sbp->f_iosize = EXT2_BLOCK_SIZE(fs);
sbp->f_blocks = es->s_blocks_count - overhead;
sbp->f_bfree = es->s_free_blocks_count;
sbp->f_bavail = sbp->f_bfree - es->s_r_blocks_count;
sbp->f_files = es->s_inodes_count;
sbp->f_ffree = es->s_free_inodes_count;
return (0);
}
/*
* Go through the disk queues to initiate sandbagged IO;
* go through the inodes to write those that have been modified;
* initiate the writing of the super block if it has been modified.
*
* Note: we are always called with the filesystem marked `MPBUSY'.
*/
static int
ext2_sync(mp, waitfor, td)
struct mount *mp;
int waitfor;
struct thread *td;
{
struct vnode *nvp, *vp;
struct inode *ip;
struct ext2mount *ump = VFSTOEXT2(mp);
struct ext2_sb_info *fs;
int error, allerror = 0;
fs = ump->um_e2fs;
if (fs->s_dirt != 0 && fs->s_rd_only != 0) { /* XXX */
printf("fs = %s\n", fs->fs_fsmnt);
panic("ext2_sync: rofs mod");
}
/*
* Write back each (modified) inode.
*/
MNT_ILOCK(mp);
loop:
MNT_VNODE_FOREACH(vp, mp, nvp) {
VI_LOCK(vp);
if (vp->v_type == VNON || (vp->v_iflag & VI_DOOMED)) {
VI_UNLOCK(vp);
continue;
}
MNT_IUNLOCK(mp);
ip = VTOI(vp);
if ((ip->i_flag &
(IN_ACCESS | IN_CHANGE | IN_MODIFIED | IN_UPDATE)) == 0 &&
(vp->v_bufobj.bo_dirty.bv_cnt == 0 ||
waitfor == MNT_LAZY)) {
VI_UNLOCK(vp);
MNT_ILOCK(mp);
continue;
}
error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK, td);
if (error) {
MNT_ILOCK(mp);
if (error == ENOENT)
goto loop;
continue;
}
if ((error = VOP_FSYNC(vp, waitfor, td)) != 0)
allerror = error;
VOP_UNLOCK(vp, 0, td);
vrele(vp);
MNT_ILOCK(mp);
}
MNT_IUNLOCK(mp);
/*
* Force stale file system control information to be flushed.
*/
if (waitfor != MNT_LAZY) {
vn_lock(ump->um_devvp, LK_EXCLUSIVE | LK_RETRY, td);
if ((error = VOP_FSYNC(ump->um_devvp, waitfor, td)) != 0)
allerror = error;
VOP_UNLOCK(ump->um_devvp, 0, td);
}
/*
* Write back modified superblock.
*/
if (fs->s_dirt != 0) {
fs->s_dirt = 0;
fs->s_es->s_wtime = time_second;
if ((error = ext2_sbupdate(ump, waitfor)) != 0)
allerror = error;
}
return (allerror);
}
/*
* Look up an EXT2FS dinode number to find its incore vnode, otherwise read it
* in from disk. If it is in core, wait for the lock bit to clear, then
* return the inode locked. Detection and handling of mount points must be
* done by the calling routine.
*/
static int
ext2_vget(mp, ino, flags, vpp)
struct mount *mp;
ino_t ino;
int flags;
struct vnode **vpp;
{
struct ext2_sb_info *fs;
struct inode *ip;
struct ext2mount *ump;
struct buf *bp;
struct vnode *vp;
struct cdev *dev;
int i, error;
int used_blocks;
error = vfs_hash_get(mp, ino, flags, curthread, vpp, NULL, NULL);
if (error || *vpp != NULL)
return (error);
ump = VFSTOEXT2(mp);
dev = ump->um_dev;
/*
* If this MALLOC() is performed after the getnewvnode()
* it might block, leaving a vnode with a NULL v_data to be
* found by ext2_sync() if a sync happens to fire right then,
* which will cause a panic because ext2_sync() blindly
* dereferences vp->v_data (as well it should).
*/
ip = malloc(sizeof(struct inode), M_EXT2NODE, M_WAITOK | M_ZERO);
/* Allocate a new vnode/inode. */
if ((error = getnewvnode("ext2fs", mp, &ext2_vnodeops, &vp)) != 0) {
*vpp = NULL;
free(ip, M_EXT2NODE);
return (error);
}
vp->v_data = ip;
ip->i_vnode = vp;
ip->i_e2fs = fs = ump->um_e2fs;
ip->i_number = ino;
error = vfs_hash_insert(vp, ino, flags, curthread, vpp, NULL, NULL);
if (error || *vpp != NULL)
return (error);
/* Read in the disk contents for the inode, copy into the inode. */
#if 0
printf("ext2_vget(%d) dbn= %d ", ino, fsbtodb(fs, ino_to_fsba(fs, ino)));
#endif
if ((error = bread(ump->um_devvp, fsbtodb(fs, ino_to_fsba(fs, ino)),
(int)fs->s_blocksize, NOCRED, &bp)) != 0) {
/*
* The inode does not contain anything useful, so it would
* be misleading to leave it on its hash chain. With mode
* still zero, it will be unlinked and returned to the free
* list by vput().
*/
vput(vp);
brelse(bp);
*vpp = NULL;
return (error);
}
/* convert ext2 inode to dinode */
ext2_ei2i((struct ext2_inode *) ((char *)bp->b_data + EXT2_INODE_SIZE *
ino_to_fsbo(fs, ino)), ip);
ip->i_block_group = ino_to_cg(fs, ino);
ip->i_next_alloc_block = 0;
ip->i_next_alloc_goal = 0;
ip->i_prealloc_count = 0;
ip->i_prealloc_block = 0;
/* now we want to make sure that block pointers for unused
blocks are zeroed out - ext2_balloc depends on this
although for regular files and directories only
*/
if(S_ISDIR(ip->i_mode) || S_ISREG(ip->i_mode)) {
used_blocks = (ip->i_size+fs->s_blocksize-1) / fs->s_blocksize;
for(i = used_blocks; i < EXT2_NDIR_BLOCKS; i++)
ip->i_db[i] = 0;
}
/*
ext2_print_inode(ip);
*/
brelse(bp);
/*
* Initialize the vnode from the inode, check for aliases.
* Note that the underlying vnode may have changed.
*/
if ((error = ext2_vinit(mp, &ext2_fifoops, &vp)) != 0) {
vput(vp);
*vpp = NULL;
return (error);
}
/*
* Finish inode initialization now that aliasing has been resolved.
*/
ip->i_devvp = ump->um_devvp;
/*
* Set up a generation number for this inode if it does not
* already have one. This should only happen on old filesystems.
*/
if (ip->i_gen == 0) {
ip->i_gen = random() / 2 + 1;
if ((vp->v_mount->mnt_flag & MNT_RDONLY) == 0)
ip->i_flag |= IN_MODIFIED;
}
*vpp = vp;
return (0);
}
/*
* File handle to vnode
*
* Have to be really careful about stale file handles:
* - check that the inode number is valid
* - call ext2_vget() to get the locked inode
* - check for an unallocated inode (i_mode == 0)
* - check that the given client host has export rights and return
* those rights via. exflagsp and credanonp
*/
static int
ext2_fhtovp(mp, fhp, vpp)
struct mount *mp;
struct fid *fhp;
struct vnode **vpp;
{
struct inode *ip;
struct ufid *ufhp;
struct vnode *nvp;
struct ext2_sb_info *fs;
int error;
ufhp = (struct ufid *)fhp;
fs = VFSTOEXT2(mp)->um_e2fs;
if (ufhp->ufid_ino < ROOTINO ||
ufhp->ufid_ino > fs->s_groups_count * fs->s_es->s_inodes_per_group)
return (ESTALE);
error = VFS_VGET(mp, ufhp->ufid_ino, LK_EXCLUSIVE, &nvp);
if (error) {
*vpp = NULLVP;
return (error);
}
ip = VTOI(nvp);
if (ip->i_mode == 0 ||
ip->i_gen != ufhp->ufid_gen || ip->i_nlink <= 0) {
vput(nvp);
*vpp = NULLVP;
return (ESTALE);
}
*vpp = nvp;
vnode_create_vobject(*vpp, 0, curthread);
return (0);
}
/*
* Vnode pointer to File handle
*/
/* ARGSUSED */
static int
ext2_vptofh(vp, fhp)
struct vnode *vp;
struct fid *fhp;
{
struct inode *ip;
struct ufid *ufhp;
ip = VTOI(vp);
ufhp = (struct ufid *)fhp;
ufhp->ufid_len = sizeof(struct ufid);
ufhp->ufid_ino = ip->i_number;
ufhp->ufid_gen = ip->i_gen;
return (0);
}
/*
* Write a superblock and associated information back to disk.
*/
static int
ext2_sbupdate(mp, waitfor)
struct ext2mount *mp;
int waitfor;
{
struct ext2_sb_info *fs = mp->um_e2fs;
struct ext2_super_block *es = fs->s_es;
struct buf *bp;
int error = 0;
/*
printf("\nupdating superblock, waitfor=%s\n", waitfor == MNT_WAIT ? "yes":"no");
*/
bp = getblk(mp->um_devvp, SBLOCK, SBSIZE, 0, 0, 0);
bcopy((caddr_t)es, bp->b_data, (u_int)sizeof(struct ext2_super_block));
if (waitfor == MNT_WAIT)
error = bwrite(bp);
else
bawrite(bp);
/*
* The buffers for group descriptors, inode bitmaps and block bitmaps
* are not busy at this point and are (hopefully) written by the
* usual sync mechanism. No need to write them here
*/
return (error);
}
/*
* Return the root of a filesystem.
*/
static int
ext2_root(mp, flags, vpp, td)
struct mount *mp;
int flags;
struct vnode **vpp;
struct thread *td;
{
struct vnode *nvp;
int error;
error = VFS_VGET(mp, (ino_t)ROOTINO, LK_EXCLUSIVE, &nvp);
if (error)
return (error);
*vpp = nvp;
return (0);
}
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