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freebsd-skq/sys/fs/msdosfs/msdosfs_vfsops.c
Kirk McKusick f257ebbb2e This change creates a new list of active vnodes associated with 
a mount point. Active vnodes are those with a non-zero use or hold
count, e.g., those vnodes that are not on the free list. Note that
this list is in addition to the list of all the vnodes associated
with a mount point.

To avoid adding another set of linkage pointers to the vnode
structure, the active list uses the existing linkage pointers
used by the free list (previously named v_freelist, now renamed
v_actfreelist).

This update adds the MNT_VNODE_FOREACH_ACTIVE interface that loops
over just the active vnodes associated with a mount point (typically
less than 1% of the vnodes associated with the mount point).

Reviewed by: kib
Tested by:   Peter Holm
MFC after:   2 weeks
2012-04-20 06:50:44 +00:00

996 lines
27 KiB
C
Raw Blame History

/* $FreeBSD$ */
/* $NetBSD: msdosfs_vfsops.c,v 1.51 1997/11/17 15:36:58 ws Exp $ */
/*-
* Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank.
* Copyright (C) 1994, 1995, 1997 TooLs GmbH.
* All rights reserved.
* Original code by Paul Popelka (paulp@uts.amdahl.com) (see below).
*
* 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 TooLs GmbH.
* 4. The name of TooLs GmbH may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``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 TOOLS GMBH 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.
*/
/*-
* Written by Paul Popelka (paulp@uts.amdahl.com)
*
* You can do anything you want with this software, just don't say you wrote
* it, and don't remove this notice.
*
* This software is provided "as is".
*
* The author supplies this software to be publicly redistributed on the
* understanding that the author is not responsible for the correct
* functioning of this software in any circumstances and is not liable for
* any damages caused by this software.
*
* October 1992
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/buf.h>
#include <sys/conf.h>
#include <sys/fcntl.h>
#include <sys/iconv.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mount.h>
#include <sys/mutex.h>
#include <sys/namei.h>
#include <sys/priv.h>
#include <sys/proc.h>
#include <sys/stat.h>
#include <sys/vnode.h>
#include <geom/geom.h>
#include <geom/geom_vfs.h>
#include <fs/msdosfs/bootsect.h>
#include <fs/msdosfs/bpb.h>
#include <fs/msdosfs/direntry.h>
#include <fs/msdosfs/denode.h>
#include <fs/msdosfs/fat.h>
#include <fs/msdosfs/msdosfsmount.h>
static const char msdosfs_lock_msg[] = "fatlk";
/* Mount options that we support. */
static const char *msdosfs_opts[] = {
"async", "noatime", "noclusterr", "noclusterw",
"export", "force", "from", "sync",
"cs_dos", "cs_local", "cs_win", "dirmask",
"gid", "kiconv", "large", "longname",
"longnames", "mask", "shortname", "shortnames",
"uid", "win95", "nowin95",
NULL
};
#if 1 /*def PC98*/
/*
* XXX - The boot signature formatted by NEC PC-98 DOS looks like a
* garbage or a random value :-{
* If you want to use that broken-signatured media, define the
* following symbol even though PC/AT.
* (ex. mount PC-98 DOS formatted FD on PC/AT)
*/
#define MSDOSFS_NOCHECKSIG
#endif
MALLOC_DEFINE(M_MSDOSFSMNT, "msdosfs_mount", "MSDOSFS mount structure");
static MALLOC_DEFINE(M_MSDOSFSFAT, "msdosfs_fat", "MSDOSFS file allocation table");
struct iconv_functions *msdosfs_iconv;
static int update_mp(struct mount *mp, struct thread *td);
static int mountmsdosfs(struct vnode *devvp, struct mount *mp);
static vfs_fhtovp_t msdosfs_fhtovp;
static vfs_mount_t msdosfs_mount;
static vfs_root_t msdosfs_root;
static vfs_statfs_t msdosfs_statfs;
static vfs_sync_t msdosfs_sync;
static vfs_unmount_t msdosfs_unmount;
/* Maximum length of a character set name (arbitrary). */
#define MAXCSLEN 64
static int
update_mp(struct mount *mp, struct thread *td)
{
struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
void *dos, *win, *local;
int error, v;
if (!vfs_getopt(mp->mnt_optnew, "kiconv", NULL, NULL)) {
if (msdosfs_iconv != NULL) {
error = vfs_getopt(mp->mnt_optnew,
"cs_win", &win, NULL);
if (!error)
error = vfs_getopt(mp->mnt_optnew,
"cs_local", &local, NULL);
if (!error)
error = vfs_getopt(mp->mnt_optnew,
"cs_dos", &dos, NULL);
if (!error) {
msdosfs_iconv->open(win, local, &pmp->pm_u2w);
msdosfs_iconv->open(local, win, &pmp->pm_w2u);
msdosfs_iconv->open(dos, local, &pmp->pm_u2d);
msdosfs_iconv->open(local, dos, &pmp->pm_d2u);
}
if (error != 0)
return (error);
} else {
pmp->pm_w2u = NULL;
pmp->pm_u2w = NULL;
pmp->pm_d2u = NULL;
pmp->pm_u2d = NULL;
}
}
if (vfs_scanopt(mp->mnt_optnew, "gid", "%d", &v) == 1)
pmp->pm_gid = v;
if (vfs_scanopt(mp->mnt_optnew, "uid", "%d", &v) == 1)
pmp->pm_uid = v;
if (vfs_scanopt(mp->mnt_optnew, "mask", "%d", &v) == 1)
pmp->pm_mask = v & ALLPERMS;
if (vfs_scanopt(mp->mnt_optnew, "dirmask", "%d", &v) == 1)
pmp->pm_dirmask = v & ALLPERMS;
vfs_flagopt(mp->mnt_optnew, "shortname",
&pmp->pm_flags, MSDOSFSMNT_SHORTNAME);
vfs_flagopt(mp->mnt_optnew, "shortnames",
&pmp->pm_flags, MSDOSFSMNT_SHORTNAME);
vfs_flagopt(mp->mnt_optnew, "longname",
&pmp->pm_flags, MSDOSFSMNT_LONGNAME);
vfs_flagopt(mp->mnt_optnew, "longnames",
&pmp->pm_flags, MSDOSFSMNT_LONGNAME);
vfs_flagopt(mp->mnt_optnew, "kiconv",
&pmp->pm_flags, MSDOSFSMNT_KICONV);
if (vfs_getopt(mp->mnt_optnew, "nowin95", NULL, NULL) == 0)
pmp->pm_flags |= MSDOSFSMNT_NOWIN95;
else
pmp->pm_flags &= ~MSDOSFSMNT_NOWIN95;
if (pmp->pm_flags & MSDOSFSMNT_NOWIN95)
pmp->pm_flags |= MSDOSFSMNT_SHORTNAME;
else if (!(pmp->pm_flags &
(MSDOSFSMNT_SHORTNAME | MSDOSFSMNT_LONGNAME))) {
struct vnode *rootvp;
/*
* Try to divine whether to support Win'95 long filenames
*/
if (FAT32(pmp))
pmp->pm_flags |= MSDOSFSMNT_LONGNAME;
else {
if ((error =
msdosfs_root(mp, LK_EXCLUSIVE, &rootvp)) != 0)
return error;
pmp->pm_flags |= findwin95(VTODE(rootvp)) ?
MSDOSFSMNT_LONGNAME : MSDOSFSMNT_SHORTNAME;
vput(rootvp);
}
}
return 0;
}
static int
msdosfs_cmount(struct mntarg *ma, void *data, uint64_t flags)
{
struct msdosfs_args args;
struct export_args exp;
int error;
if (data == NULL)
return (EINVAL);
error = copyin(data, &args, sizeof args);
if (error)
return (error);
vfs_oexport_conv(&args.export, &exp);
ma = mount_argsu(ma, "from", args.fspec, MAXPATHLEN);
ma = mount_arg(ma, "export", &exp, sizeof(exp));
ma = mount_argf(ma, "uid", "%d", args.uid);
ma = mount_argf(ma, "gid", "%d", args.gid);
ma = mount_argf(ma, "mask", "%d", args.mask);
ma = mount_argf(ma, "dirmask", "%d", args.dirmask);
ma = mount_argb(ma, args.flags & MSDOSFSMNT_SHORTNAME, "noshortname");
ma = mount_argb(ma, args.flags & MSDOSFSMNT_LONGNAME, "nolongname");
ma = mount_argb(ma, !(args.flags & MSDOSFSMNT_NOWIN95), "nowin95");
ma = mount_argb(ma, args.flags & MSDOSFSMNT_KICONV, "nokiconv");
ma = mount_argsu(ma, "cs_win", args.cs_win, MAXCSLEN);
ma = mount_argsu(ma, "cs_dos", args.cs_dos, MAXCSLEN);
ma = mount_argsu(ma, "cs_local", args.cs_local, MAXCSLEN);
error = kernel_mount(ma, flags);
return (error);
}
/*
* mp - path - addr in user space of mount point (ie /usr or whatever)
* data - addr in user space of mount params including the name of the block
* special file to treat as a filesystem.
*/
static int
msdosfs_mount(struct mount *mp)
{
struct vnode *devvp; /* vnode for blk device to mount */
struct thread *td;
/* msdosfs specific mount control block */
struct msdosfsmount *pmp = NULL;
struct nameidata ndp;
int error, flags;
accmode_t accmode;
char *from;
td = curthread;
if (vfs_filteropt(mp->mnt_optnew, msdosfs_opts))
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) {
pmp = VFSTOMSDOSFS(mp);
if (vfs_flagopt(mp->mnt_optnew, "export", NULL, 0)) {
/*
* Forbid export requests if filesystem has
* MSDOSFS_LARGEFS flag set.
*/
if ((pmp->pm_flags & MSDOSFS_LARGEFS) != 0) {
vfs_mount_error(mp,
"MSDOSFS_LARGEFS flag set, cannot export");
return (EOPNOTSUPP);
}
}
if (!(pmp->pm_flags & MSDOSFSMNT_RONLY) &&
vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) {
error = VFS_SYNC(mp, MNT_WAIT);
if (error)
return (error);
flags = WRITECLOSE;
if (mp->mnt_flag & MNT_FORCE)
flags |= FORCECLOSE;
error = vflush(mp, 0, flags, td);
if (error)
return (error);
/*
* Now the volume is clean. Mark it so while the
* device is still rw.
*/
error = markvoldirty(pmp, 0);
if (error) {
(void)markvoldirty(pmp, 1);
return (error);
}
/* Downgrade the device from rw to ro. */
DROP_GIANT();
g_topology_lock();
error = g_access(pmp->pm_cp, 0, -1, 0);
g_topology_unlock();
PICKUP_GIANT();
if (error) {
(void)markvoldirty(pmp, 1);
return (error);
}
/*
* Backing out after an error was painful in the
* above. Now we are committed to succeeding.
*/
pmp->pm_fmod = 0;
pmp->pm_flags |= MSDOSFSMNT_RONLY;
MNT_ILOCK(mp);
mp->mnt_flag |= MNT_RDONLY;
MNT_IUNLOCK(mp);
} else if ((pmp->pm_flags & MSDOSFSMNT_RONLY) &&
!vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) {
/*
* If upgrade to read-write by non-root, then verify
* that user has necessary permissions on the device.
*/
devvp = pmp->pm_devvp;
vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
error = VOP_ACCESS(devvp, VREAD | VWRITE,
td->td_ucred, td);
if (error)
error = priv_check(td, PRIV_VFS_MOUNT_PERM);
if (error) {
VOP_UNLOCK(devvp, 0);
return (error);
}
VOP_UNLOCK(devvp, 0);
DROP_GIANT();
g_topology_lock();
error = g_access(pmp->pm_cp, 0, 1, 0);
g_topology_unlock();
PICKUP_GIANT();
if (error)
return (error);
pmp->pm_fmod = 1;
pmp->pm_flags &= ~MSDOSFSMNT_RONLY;
MNT_ILOCK(mp);
mp->mnt_flag &= ~MNT_RDONLY;
MNT_IUNLOCK(mp);
/* Now that the volume is modifiable, mark it dirty. */
error = markvoldirty(pmp, 1);
if (error)
return (error);
}
}
/*
* Not an update, or updating the name: look up the name
* and verify that it refers to a sensible disk device.
*/
if (vfs_getopt(mp->mnt_optnew, "from", (void **)&from, NULL))
return (EINVAL);
NDINIT(&ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, from, td);
error = namei(&ndp);
if (error)
return (error);
devvp = ndp.ni_vp;
NDFREE(&ndp, NDF_ONLY_PNBUF);
if (!vn_isdisk(devvp, &error)) {
vput(devvp);
return (error);
}
/*
* If mount by non-root, then verify that user has necessary
* permissions on the device.
*/
accmode = VREAD;
if ((mp->mnt_flag & MNT_RDONLY) == 0)
accmode |= VWRITE;
error = VOP_ACCESS(devvp, accmode, td->td_ucred, td);
if (error)
error = priv_check(td, PRIV_VFS_MOUNT_PERM);
if (error) {
vput(devvp);
return (error);
}
if ((mp->mnt_flag & MNT_UPDATE) == 0) {
error = mountmsdosfs(devvp, mp);
#ifdef MSDOSFS_DEBUG /* only needed for the printf below */
pmp = VFSTOMSDOSFS(mp);
#endif
} else {
vput(devvp);
if (devvp != pmp->pm_devvp)
return (EINVAL); /* XXX needs translation */
}
if (error) {
vrele(devvp);
return (error);
}
error = update_mp(mp, td);
if (error) {
if ((mp->mnt_flag & MNT_UPDATE) == 0)
msdosfs_unmount(mp, MNT_FORCE);
return error;
}
if (devvp->v_type == VCHR && devvp->v_rdev != NULL)
devvp->v_rdev->si_mountpt = mp;
vfs_mountedfrom(mp, from);
#ifdef MSDOSFS_DEBUG
printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap);
#endif
return (0);
}
static int
mountmsdosfs(struct vnode *devvp, struct mount *mp)
{
struct msdosfsmount *pmp;
struct buf *bp;
struct cdev *dev;
union bootsector *bsp;
struct byte_bpb33 *b33;
struct byte_bpb50 *b50;
struct byte_bpb710 *b710;
u_int8_t SecPerClust;
u_long clusters;
int ronly, error;
struct g_consumer *cp;
struct bufobj *bo;
bp = NULL; /* This and pmp both used in error_exit. */
pmp = NULL;
ronly = (mp->mnt_flag & MNT_RDONLY) != 0;
dev = devvp->v_rdev;
dev_ref(dev);
DROP_GIANT();
g_topology_lock();
error = g_vfs_open(devvp, &cp, "msdosfs", ronly ? 0 : 1);
g_topology_unlock();
PICKUP_GIANT();
VOP_UNLOCK(devvp, 0);
if (error)
goto error_exit;
bo = &devvp->v_bufobj;
/*
* Read the boot sector of the filesystem, and then check the
* boot signature. If not a dos boot sector then error out.
*
* NOTE: 8192 is a magic size that works for ffs.
*/
error = bread(devvp, 0, 8192, NOCRED, &bp);
if (error)
goto error_exit;
bp->b_flags |= B_AGE;
bsp = (union bootsector *)bp->b_data;
b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB;
b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB;
b710 = (struct byte_bpb710 *)bsp->bs710.bsBPB;
#ifndef MSDOSFS_NOCHECKSIG
if (bsp->bs50.bsBootSectSig0 != BOOTSIG0
|| bsp->bs50.bsBootSectSig1 != BOOTSIG1) {
error = EINVAL;
goto error_exit;
}
#endif
pmp = malloc(sizeof *pmp, M_MSDOSFSMNT, M_WAITOK | M_ZERO);
pmp->pm_mountp = mp;
pmp->pm_cp = cp;
pmp->pm_bo = bo;
lockinit(&pmp->pm_fatlock, 0, msdosfs_lock_msg, 0, 0);
/*
* Initialize ownerships and permissions, since nothing else will
* initialize them iff we are mounting root.
*/
pmp->pm_uid = UID_ROOT;
pmp->pm_gid = GID_WHEEL;
pmp->pm_mask = pmp->pm_dirmask = S_IXUSR | S_IXGRP | S_IXOTH |
S_IRUSR | S_IRGRP | S_IROTH | S_IWUSR;
/*
* Experimental support for large MS-DOS filesystems.
* WARNING: This uses at least 32 bytes of kernel memory (which is not
* reclaimed until the FS is unmounted) for each file on disk to map
* between the 32-bit inode numbers used by VFS and the 64-bit
* pseudo-inode numbers used internally by msdosfs. This is only
* safe to use in certain controlled situations (e.g. read-only FS
* with less than 1 million files).
* Since the mappings do not persist across unmounts (or reboots), these
* filesystems are not suitable for exporting through NFS, or any other
* application that requires fixed inode numbers.
*/
vfs_flagopt(mp->mnt_optnew, "large", &pmp->pm_flags, MSDOSFS_LARGEFS);
/*
* Compute several useful quantities from the bpb in the
* bootsector. Copy in the dos 5 variant of the bpb then fix up
* the fields that are different between dos 5 and dos 3.3.
*/
SecPerClust = b50->bpbSecPerClust;
pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec);
if (pmp->pm_BytesPerSec < DEV_BSIZE) {
error = EINVAL;
goto error_exit;
}
pmp->pm_ResSectors = getushort(b50->bpbResSectors);
pmp->pm_FATs = b50->bpbFATs;
pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts);
pmp->pm_Sectors = getushort(b50->bpbSectors);
pmp->pm_FATsecs = getushort(b50->bpbFATsecs);
pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack);
pmp->pm_Heads = getushort(b50->bpbHeads);
pmp->pm_Media = b50->bpbMedia;
/* calculate the ratio of sector size to DEV_BSIZE */
pmp->pm_BlkPerSec = pmp->pm_BytesPerSec / DEV_BSIZE;
/*
* We don't check pm_Heads nor pm_SecPerTrack, because
* these may not be set for EFI file systems. We don't
* use these anyway, so we're unaffected if they are
* invalid.
*/
if (!pmp->pm_BytesPerSec || !SecPerClust) {
error = EINVAL;
goto error_exit;
}
if (pmp->pm_Sectors == 0) {
pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs);
pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors);
} else {
pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs);
pmp->pm_HugeSectors = pmp->pm_Sectors;
}
if (!(pmp->pm_flags & MSDOSFS_LARGEFS)) {
if (pmp->pm_HugeSectors > 0xffffffff /
(pmp->pm_BytesPerSec / sizeof(struct direntry)) + 1) {
/*
* We cannot deal currently with this size of disk
* due to fileid limitations (see msdosfs_getattr and
* msdosfs_readdir)
*/
error = EINVAL;
vfs_mount_error(mp,
"Disk too big, try '-o large' mount option");
goto error_exit;
}
}
if (pmp->pm_RootDirEnts == 0) {
if (pmp->pm_Sectors
|| pmp->pm_FATsecs
|| getushort(b710->bpbFSVers)) {
error = EINVAL;
#ifdef MSDOSFS_DEBUG
printf("mountmsdosfs(): bad FAT32 filesystem\n");
#endif
goto error_exit;
}
pmp->pm_fatmask = FAT32_MASK;
pmp->pm_fatmult = 4;
pmp->pm_fatdiv = 1;
pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs);
if (getushort(b710->bpbExtFlags) & FATMIRROR)
pmp->pm_curfat = getushort(b710->bpbExtFlags) & FATNUM;
else
pmp->pm_flags |= MSDOSFS_FATMIRROR;
} else
pmp->pm_flags |= MSDOSFS_FATMIRROR;
/*
* Check a few values (could do some more):
* - logical sector size: power of 2, >= block size
* - sectors per cluster: power of 2, >= 1
* - number of sectors: >= 1, <= size of partition
* - number of FAT sectors: >= 1
*/
if ( (SecPerClust == 0)
|| (SecPerClust & (SecPerClust - 1))
|| (pmp->pm_BytesPerSec < DEV_BSIZE)
|| (pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1))
|| (pmp->pm_HugeSectors == 0)
|| (pmp->pm_FATsecs == 0)
|| (SecPerClust * pmp->pm_BlkPerSec > MAXBSIZE / DEV_BSIZE)
) {
error = EINVAL;
goto error_exit;
}
pmp->pm_HugeSectors *= pmp->pm_BlkPerSec;
pmp->pm_HiddenSects *= pmp->pm_BlkPerSec; /* XXX not used? */
pmp->pm_FATsecs *= pmp->pm_BlkPerSec;
SecPerClust *= pmp->pm_BlkPerSec;
pmp->pm_fatblk = pmp->pm_ResSectors * pmp->pm_BlkPerSec;
if (FAT32(pmp)) {
pmp->pm_rootdirblk = getulong(b710->bpbRootClust);
pmp->pm_firstcluster = pmp->pm_fatblk
+ (pmp->pm_FATs * pmp->pm_FATsecs);
pmp->pm_fsinfo = getushort(b710->bpbFSInfo) * pmp->pm_BlkPerSec;
} else {
pmp->pm_rootdirblk = pmp->pm_fatblk +
(pmp->pm_FATs * pmp->pm_FATsecs);
pmp->pm_rootdirsize = (pmp->pm_RootDirEnts * sizeof(struct direntry)
+ DEV_BSIZE - 1)
/ DEV_BSIZE; /* in blocks */
pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize;
}
pmp->pm_maxcluster = (pmp->pm_HugeSectors - pmp->pm_firstcluster) /
SecPerClust + 1;
pmp->pm_fatsize = pmp->pm_FATsecs * DEV_BSIZE; /* XXX not used? */
if (pmp->pm_fatmask == 0) {
if (pmp->pm_maxcluster
<= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) {
/*
* This will usually be a floppy disk. This size makes
* sure that one fat entry will not be split across
* multiple blocks.
*/
pmp->pm_fatmask = FAT12_MASK;
pmp->pm_fatmult = 3;
pmp->pm_fatdiv = 2;
} else {
pmp->pm_fatmask = FAT16_MASK;
pmp->pm_fatmult = 2;
pmp->pm_fatdiv = 1;
}
}
clusters = (pmp->pm_fatsize / pmp->pm_fatmult) * pmp->pm_fatdiv;
if (pmp->pm_maxcluster >= clusters) {
#ifdef MSDOSFS_DEBUG
printf("Warning: number of clusters (%ld) exceeds FAT "
"capacity (%ld)\n", pmp->pm_maxcluster + 1, clusters);
#endif
pmp->pm_maxcluster = clusters - 1;
}
if (FAT12(pmp))
pmp->pm_fatblocksize = 3 * 512;
else
pmp->pm_fatblocksize = PAGE_SIZE;
pmp->pm_fatblocksize = roundup(pmp->pm_fatblocksize,
pmp->pm_BytesPerSec);
pmp->pm_fatblocksec = pmp->pm_fatblocksize / DEV_BSIZE;
pmp->pm_bnshift = ffs(DEV_BSIZE) - 1;
/*
* Compute mask and shift value for isolating cluster relative byte
* offsets and cluster numbers from a file offset.
*/
pmp->pm_bpcluster = SecPerClust * DEV_BSIZE;
pmp->pm_crbomask = pmp->pm_bpcluster - 1;
pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1;
/*
* Check for valid cluster size
* must be a power of 2
*/
if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) {
error = EINVAL;
goto error_exit;
}
/*
* Release the bootsector buffer.
*/
brelse(bp);
bp = NULL;
/*
* Check the fsinfo sector if we have one. Silently fix up our
* in-core copy of fp->fsinxtfree if it is unknown (0xffffffff)
* or too large. Ignore fp->fsinfree for now, since we need to
* read the entire FAT anyway to fill the inuse map.
*/
if (pmp->pm_fsinfo) {
struct fsinfo *fp;
if ((error = bread(devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec,
NOCRED, &bp)) != 0)
goto error_exit;
fp = (struct fsinfo *)bp->b_data;
if (!bcmp(fp->fsisig1, "RRaA", 4)
&& !bcmp(fp->fsisig2, "rrAa", 4)
&& !bcmp(fp->fsisig3, "\0\0\125\252", 4)) {
pmp->pm_nxtfree = getulong(fp->fsinxtfree);
if (pmp->pm_nxtfree > pmp->pm_maxcluster)
pmp->pm_nxtfree = CLUST_FIRST;
} else
pmp->pm_fsinfo = 0;
brelse(bp);
bp = NULL;
}
/*
* Finish initializing pmp->pm_nxtfree (just in case the first few
* sectors aren't properly reserved in the FAT). This completes
* the fixup for fp->fsinxtfree, and fixes up the zero-initialized
* value if there is no fsinfo. We will use pmp->pm_nxtfree
* internally even if there is no fsinfo.
*/
if (pmp->pm_nxtfree < CLUST_FIRST)
pmp->pm_nxtfree = CLUST_FIRST;
/*
* Allocate memory for the bitmap of allocated clusters, and then
* fill it in.
*/
pmp->pm_inusemap = malloc(howmany(pmp->pm_maxcluster + 1, N_INUSEBITS)
* sizeof(*pmp->pm_inusemap),
M_MSDOSFSFAT, M_WAITOK);
/*
* fillinusemap() needs pm_devvp.
*/
pmp->pm_devvp = devvp;
pmp->pm_dev = dev;
/*
* Have the inuse map filled in.
*/
MSDOSFS_LOCK_MP(pmp);
error = fillinusemap(pmp);
MSDOSFS_UNLOCK_MP(pmp);
if (error != 0)
goto error_exit;
/*
* If they want fat updates to be synchronous then let them suffer
* the performance degradation in exchange for the on disk copy of
* the fat being correct just about all the time. I suppose this
* would be a good thing to turn on if the kernel is still flakey.
*/
if (mp->mnt_flag & MNT_SYNCHRONOUS)
pmp->pm_flags |= MSDOSFSMNT_WAITONFAT;
/*
* Finish up.
*/
if (ronly)
pmp->pm_flags |= MSDOSFSMNT_RONLY;
else {
if ((error = markvoldirty(pmp, 1)) != 0) {
(void)markvoldirty(pmp, 0);
goto error_exit;
}
pmp->pm_fmod = 1;
}
mp->mnt_data = pmp;
mp->mnt_stat.f_fsid.val[0] = dev2udev(dev);
mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum;
MNT_ILOCK(mp);
mp->mnt_flag |= MNT_LOCAL;
mp->mnt_kern_flag |= MNTK_MPSAFE;
MNT_IUNLOCK(mp);
if (pmp->pm_flags & MSDOSFS_LARGEFS)
msdosfs_fileno_init(mp);
return 0;
error_exit:
if (bp)
brelse(bp);
if (cp != NULL) {
DROP_GIANT();
g_topology_lock();
g_vfs_close(cp);
g_topology_unlock();
PICKUP_GIANT();
}
if (pmp) {
lockdestroy(&pmp->pm_fatlock);
if (pmp->pm_inusemap)
free(pmp->pm_inusemap, M_MSDOSFSFAT);
free(pmp, M_MSDOSFSMNT);
mp->mnt_data = NULL;
}
dev_rel(dev);
return (error);
}
/*
* Unmount the filesystem described by mp.
*/
static int
msdosfs_unmount(struct mount *mp, int mntflags)
{
struct msdosfsmount *pmp;
int error, flags;
flags = 0;
if (mntflags & MNT_FORCE)
flags |= FORCECLOSE;
error = vflush(mp, 0, flags, curthread);
if (error && error != ENXIO)
return error;
pmp = VFSTOMSDOSFS(mp);
if ((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0) {
error = markvoldirty(pmp, 0);
if (error && error != ENXIO) {
(void)markvoldirty(pmp, 1);
return (error);
}
}
if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdosfs_iconv) {
if (pmp->pm_w2u)
msdosfs_iconv->close(pmp->pm_w2u);
if (pmp->pm_u2w)
msdosfs_iconv->close(pmp->pm_u2w);
if (pmp->pm_d2u)
msdosfs_iconv->close(pmp->pm_d2u);
if (pmp->pm_u2d)
msdosfs_iconv->close(pmp->pm_u2d);
}
#ifdef MSDOSFS_DEBUG
{
struct vnode *vp = pmp->pm_devvp;
struct bufobj *bo;
bo = &vp->v_bufobj;
BO_LOCK(bo);
VI_LOCK(vp);
vn_printf(vp,
"msdosfs_umount(): just before calling VOP_CLOSE()\n");
printf("freef %p, freeb %p, mount %p\n",
TAILQ_NEXT(vp, v_actfreelist), vp->v_actfreelist.tqe_prev,
vp->v_mount);
printf("cleanblkhd %p, dirtyblkhd %p, numoutput %ld, type %d\n",
TAILQ_FIRST(&vp->v_bufobj.bo_clean.bv_hd),
TAILQ_FIRST(&vp->v_bufobj.bo_dirty.bv_hd),
vp->v_bufobj.bo_numoutput, vp->v_type);
VI_UNLOCK(vp);
BO_UNLOCK(bo);
}
#endif
DROP_GIANT();
if (pmp->pm_devvp->v_type == VCHR && pmp->pm_devvp->v_rdev != NULL)
pmp->pm_devvp->v_rdev->si_mountpt = NULL;
g_topology_lock();
g_vfs_close(pmp->pm_cp);
g_topology_unlock();
PICKUP_GIANT();
vrele(pmp->pm_devvp);
dev_rel(pmp->pm_dev);
free(pmp->pm_inusemap, M_MSDOSFSFAT);
if (pmp->pm_flags & MSDOSFS_LARGEFS)
msdosfs_fileno_free(mp);
lockdestroy(&pmp->pm_fatlock);
free(pmp, M_MSDOSFSMNT);
mp->mnt_data = NULL;
MNT_ILOCK(mp);
mp->mnt_flag &= ~MNT_LOCAL;
MNT_IUNLOCK(mp);
return (error);
}
static int
msdosfs_root(struct mount *mp, int flags, struct vnode **vpp)
{
struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
struct denode *ndep;
int error;
#ifdef MSDOSFS_DEBUG
printf("msdosfs_root(); mp %p, pmp %p\n", mp, pmp);
#endif
error = deget(pmp, MSDOSFSROOT, MSDOSFSROOT_OFS, &ndep);
if (error)
return (error);
*vpp = DETOV(ndep);
return (0);
}
static int
msdosfs_statfs(struct mount *mp, struct statfs *sbp)
{
struct msdosfsmount *pmp;
pmp = VFSTOMSDOSFS(mp);
sbp->f_bsize = pmp->pm_bpcluster;
sbp->f_iosize = pmp->pm_bpcluster;
sbp->f_blocks = pmp->pm_maxcluster + 1;
sbp->f_bfree = pmp->pm_freeclustercount;
sbp->f_bavail = pmp->pm_freeclustercount;
sbp->f_files = pmp->pm_RootDirEnts; /* XXX */
sbp->f_ffree = 0; /* what to put in here? */
return (0);
}
static int
msdosfs_sync(struct mount *mp, int waitfor)
{
struct vnode *vp, *nvp;
struct thread *td;
struct denode *dep;
struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
int error, allerror = 0;
td = curthread;
/*
* If we ever switch to not updating all of the fats all the time,
* this would be the place to update them from the first one.
*/
if (pmp->pm_fmod != 0) {
if (pmp->pm_flags & MSDOSFSMNT_RONLY)
panic("msdosfs_sync: rofs mod");
else {
/* update fats here */
}
}
/*
* Write back each (modified) denode.
*/
loop:
MNT_VNODE_FOREACH_ALL(vp, mp, nvp) {
if (vp->v_type == VNON) {
VI_UNLOCK(vp);
continue;
}
dep = VTODE(vp);
if ((dep->de_flag &
(DE_ACCESS | DE_CREATE | DE_UPDATE | DE_MODIFIED)) == 0 &&
(vp->v_bufobj.bo_dirty.bv_cnt == 0 ||
waitfor == MNT_LAZY)) {
VI_UNLOCK(vp);
continue;
}
error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK, td);
if (error) {
if (error == ENOENT)
goto loop;
continue;
}
error = VOP_FSYNC(vp, waitfor, td);
if (error)
allerror = error;
VOP_UNLOCK(vp, 0);
vrele(vp);
}
/*
* Flush filesystem control info.
*/
if (waitfor != MNT_LAZY) {
vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY);
error = VOP_FSYNC(pmp->pm_devvp, waitfor, td);
if (error)
allerror = error;
VOP_UNLOCK(pmp->pm_devvp, 0);
}
return (allerror);
}
static int
msdosfs_fhtovp(struct mount *mp, struct fid *fhp, int flags, struct vnode **vpp)
{
struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
struct defid *defhp = (struct defid *) fhp;
struct denode *dep;
int error;
error = deget(pmp, defhp->defid_dirclust, defhp->defid_dirofs, &dep);
if (error) {
*vpp = NULLVP;
return (error);
}
*vpp = DETOV(dep);
vnode_create_vobject(*vpp, dep->de_FileSize, curthread);
return (0);
}
static struct vfsops msdosfs_vfsops = {
.vfs_fhtovp = msdosfs_fhtovp,
.vfs_mount = msdosfs_mount,
.vfs_cmount = msdosfs_cmount,
.vfs_root = msdosfs_root,
.vfs_statfs = msdosfs_statfs,
.vfs_sync = msdosfs_sync,
.vfs_unmount = msdosfs_unmount,
};
VFS_SET(msdosfs_vfsops, msdosfs, 0);
MODULE_VERSION(msdosfs, 1);
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