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freebsd/sys/msdosfs/msdosfs_vfsops.c
Adrian Chadd f3a90da995 Reviewed by: jlemon 
An initial tidyup of the mount() syscall and VFS mount code.

This code replaces the earlier work done by jlemon in an attempt to
make linux_mount() work.

* the guts of the mount work has been moved into vfs_mount().

* move `type', `path' and `flags' from being userland variables into being
  kernel variables in vfs_mount(). `data' remains a pointer into
  userspace.

* Attempt to verify the `type' and `path' strings passed to vfs_mount()
  aren't too long.

* rework mount() and linux_mount() to take the userland parameters
  (besides data, as mentioned) and pass kernel variables to vfs_mount().
  (linux_mount() already did this, I've just tidied it up a little more.)

* remove the copyin*() stuff for `path'. `data' still requires copyin*()
  since its a pointer into userland.

* set `mount->mnt_statf_mntonname' in vfs_mount() rather than in each
  filesystem.  This variable is generally initialised with `path', and
  each filesystem can override it if they want to.

* NOTE: f_mntonname is intiailised with "/" in the case of a root mount.
2001-03-01 21:00:17 +00:00

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/* $FreeBSD$ */
/* $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/conf.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/fcntl.h>
#include <sys/malloc.h>
#include <sys/stat.h> /* defines ALLPERMS */
#include <sys/mutex.h>
#include <msdosfs/bpb.h>
#include <msdosfs/bootsect.h>
#include <msdosfs/direntry.h>
#include <msdosfs/denode.h>
#include <msdosfs/msdosfsmount.h>
#include <msdosfs/fat.h>
#define MSDOSFS_DFLTBSIZE 4096
#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");
static int update_mp __P((struct mount *mp, struct msdosfs_args *argp));
static int mountmsdosfs __P((struct vnode *devvp, struct mount *mp,
struct proc *p, struct msdosfs_args *argp));
static int msdosfs_fhtovp __P((struct mount *, struct fid *,
struct vnode **));
static int msdosfs_checkexp __P((struct mount *, struct sockaddr *,
int *, struct ucred **));
static int msdosfs_mount __P((struct mount *, char *, caddr_t,
struct nameidata *, struct proc *));
static int msdosfs_root __P((struct mount *, struct vnode **));
static int msdosfs_statfs __P((struct mount *, struct statfs *,
struct proc *));
static int msdosfs_sync __P((struct mount *, int, struct ucred *,
struct proc *));
static int msdosfs_unmount __P((struct mount *, int, struct proc *));
static int msdosfs_vptofh __P((struct vnode *, struct fid *));
static int
update_mp(mp, argp)
struct mount *mp;
struct msdosfs_args *argp;
{
struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
int error;
pmp->pm_gid = argp->gid;
pmp->pm_uid = argp->uid;
pmp->pm_mask = argp->mask & ALLPERMS;
pmp->pm_flags |= argp->flags & MSDOSFSMNT_MNTOPT;
if (pmp->pm_flags & MSDOSFSMNT_U2WTABLE) {
bcopy(argp->u2w, pmp->pm_u2w, sizeof(pmp->pm_u2w));
bcopy(argp->d2u, pmp->pm_d2u, sizeof(pmp->pm_d2u));
bcopy(argp->u2d, pmp->pm_u2d, sizeof(pmp->pm_u2d));
}
if (pmp->pm_flags & MSDOSFSMNT_ULTABLE) {
bcopy(argp->ul, pmp->pm_ul, sizeof(pmp->pm_ul));
bcopy(argp->lu, pmp->pm_lu, sizeof(pmp->pm_lu));
}
#ifndef __FreeBSD__
/*
* GEMDOS knows nothing (yet) about win95
*/
if (pmp->pm_flags & MSDOSFSMNT_GEMDOSFS)
pmp->pm_flags |= MSDOSFSMNT_NOWIN95;
#endif
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, &rootvp)) != 0)
return error;
pmp->pm_flags |= findwin95(VTODE(rootvp))
? MSDOSFSMNT_LONGNAME
: MSDOSFSMNT_SHORTNAME;
vput(rootvp);
}
}
return 0;
}
#ifndef __FreeBSD__
int
msdosfs_mountroot()
{
register struct mount *mp;
struct proc *p = curproc; /* XXX */
size_t size;
int error;
struct msdosfs_args args;
if (root_device->dv_class != DV_DISK)
return (ENODEV);
/*
* Get vnodes for swapdev and rootdev.
*/
if (bdevvp(rootdev, &rootvp))
panic("msdosfs_mountroot: can't setup rootvp");
mp = malloc((u_long)sizeof(struct mount), M_MOUNT, M_WAITOK | M_ZERO);
mp->mnt_op = &msdosfs_vfsops;
mp->mnt_flag = 0;
LIST_INIT(&mp->mnt_vnodelist);
args.flags = 0;
args.uid = 0;
args.gid = 0;
args.mask = 0777;
if ((error = mountmsdosfs(rootvp, mp, p, &args)) != 0) {
free(mp, M_MOUNT);
return (error);
}
if ((error = update_mp(mp, &args)) != 0) {
(void)msdosfs_unmount(mp, 0, p);
free(mp, M_MOUNT);
return (error);
}
if ((error = vfs_lock(mp)) != 0) {
(void)msdosfs_unmount(mp, 0, p);
free(mp, M_MOUNT);
return (error);
}
TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list);
mp->mnt_vnodecovered = NULLVP;
(void) copystr("/", mp->mnt_stat.f_mntonname, MNAMELEN - 1,
&size);
bzero(mp->mnt_stat.f_mntonname + size, MNAMELEN - size);
(void) copystr(ROOTNAME, mp->mnt_stat.f_mntfromname, MNAMELEN - 1,
&size);
bzero(mp->mnt_stat.f_mntfromname + size, MNAMELEN - size);
(void)msdosfs_statfs(mp, &mp->mnt_stat, p);
vfs_unlock(mp);
return (0);
}
#endif
/*
* 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(mp, path, data, ndp, p)
struct mount *mp;
char *path;
caddr_t data;
struct nameidata *ndp;
struct proc *p;
{
struct vnode *devvp; /* vnode for blk device to mount */
struct msdosfs_args args; /* will hold data from mount request */
/* msdosfs specific mount control block */
struct msdosfsmount *pmp = NULL;
size_t size;
int error, flags;
mode_t accessmode;
error = copyin(data, (caddr_t)&args, sizeof(struct msdosfs_args));
if (error)
return (error);
if (args.magic != MSDOSFS_ARGSMAGIC)
args.flags = 0;
/*
* 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);
error = 0;
if (!(pmp->pm_flags & MSDOSFSMNT_RONLY) && (mp->mnt_flag & MNT_RDONLY)) {
flags = WRITECLOSE;
if (mp->mnt_flag & MNT_FORCE)
flags |= FORCECLOSE;
error = vflush(mp, NULLVP, flags);
}
if (!error && (mp->mnt_flag & MNT_RELOAD))
/* not yet implemented */
error = EOPNOTSUPP;
if (error)
return (error);
if ((pmp->pm_flags & MSDOSFSMNT_RONLY) && (mp->mnt_kern_flag & MNTK_WANTRDWR)) {
/*
* If upgrade to read-write by non-root, then verify
* that user has necessary permissions on the device.
*/
if (p->p_ucred->cr_uid != 0) {
devvp = pmp->pm_devvp;
vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, p);
error = VOP_ACCESS(devvp, VREAD | VWRITE,
p->p_ucred, p);
if (error) {
VOP_UNLOCK(devvp, 0, p);
return (error);
}
VOP_UNLOCK(devvp, 0, p);
}
pmp->pm_flags &= ~MSDOSFSMNT_RONLY;
}
if (args.fspec == 0) {
#ifdef __notyet__ /* doesn't work correctly with current mountd XXX */
if (args.flags & MSDOSFSMNT_MNTOPT) {
pmp->pm_flags &= ~MSDOSFSMNT_MNTOPT;
pmp->pm_flags |= args.flags & MSDOSFSMNT_MNTOPT;
if (pmp->pm_flags & MSDOSFSMNT_NOWIN95)
pmp->pm_flags |= MSDOSFSMNT_SHORTNAME;
}
#endif
/*
* Process export requests.
*/
return (vfs_export(mp, &pmp->pm_export, &args.export));
}
}
/*
* Not an update, or updating the name: look up the name
* and verify that it refers to a sensible block device.
*/
NDINIT(ndp, LOOKUP, FOLLOW, UIO_USERSPACE, args.fspec, p);
error = namei(ndp);
if (error)
return (error);
devvp = ndp->ni_vp;
NDFREE(ndp, NDF_ONLY_PNBUF);
if (!vn_isdisk(devvp, &error)) {
vrele(devvp);
return (error);
}
/*
* If mount by non-root, then verify that user has necessary
* permissions on the device.
*/
if (p->p_ucred->cr_uid != 0) {
accessmode = VREAD;
if ((mp->mnt_flag & MNT_RDONLY) == 0)
accessmode |= VWRITE;
vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, p);
error = VOP_ACCESS(devvp, accessmode, p->p_ucred, p);
if (error) {
vput(devvp);
return (error);
}
VOP_UNLOCK(devvp, 0, p);
}
if ((mp->mnt_flag & MNT_UPDATE) == 0) {
error = mountmsdosfs(devvp, mp, p, &args);
#ifdef MSDOSFS_DEBUG /* only needed for the printf below */
pmp = VFSTOMSDOSFS(mp);
#endif
} else {
if (devvp != pmp->pm_devvp)
error = EINVAL; /* XXX needs translation */
else
vrele(devvp);
}
if (error) {
vrele(devvp);
return (error);
}
error = update_mp(mp, &args);
if (error) {
msdosfs_unmount(mp, MNT_FORCE, p);
return error;
}
(void) copyinstr(args.fspec, mp->mnt_stat.f_mntfromname, MNAMELEN - 1,
&size);
bzero(mp->mnt_stat.f_mntfromname + size, MNAMELEN - size);
(void) msdosfs_statfs(mp, &mp->mnt_stat, p);
#ifdef MSDOSFS_DEBUG
printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap);
#endif
return (0);
}
static int
mountmsdosfs(devvp, mp, p, argp)
struct vnode *devvp;
struct mount *mp;
struct proc *p;
struct msdosfs_args *argp;
{
struct msdosfsmount *pmp;
struct buf *bp;
dev_t dev = devvp->v_rdev;
#ifndef __FreeBSD__
struct partinfo dpart;
int bsize = 0, dtype = 0, tmp;
#endif
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;
/*
* Disallow multiple mounts of the same device.
* Disallow mounting of a device that is currently in use
* (except for root, which might share swap device for miniroot).
* Flush out any old buffers remaining from a previous use.
*/
error = vfs_mountedon(devvp);
if (error)
return (error);
if (vcount(devvp) > 1 && devvp != rootvp)
return (EBUSY);
vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, p);
error = vinvalbuf(devvp, V_SAVE, p->p_ucred, p, 0, 0);
VOP_UNLOCK(devvp, 0, p);
if (error)
return (error);
ronly = (mp->mnt_flag & MNT_RDONLY) != 0;
vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, p);
error = VOP_OPEN(devvp, ronly ? FREAD : FREAD|FWRITE, FSCRED, p);
VOP_UNLOCK(devvp, 0, p);
if (error)
return (error);
bp = NULL; /* both used in error_exit */
pmp = NULL;
#ifndef __FreeBSD__
if (argp->flags & MSDOSFSMNT_GEMDOSFS) {
/*
* We need the disklabel to calculate the size of a FAT entry
* later on. Also make sure the partition contains a filesystem
* of type FS_MSDOS. This doesn't work for floppies, so we have
* to check for them too.
*
* At least some parts of the msdos fs driver seem to assume
* that the size of a disk block will always be 512 bytes.
* Let's check it...
*/
error = VOP_IOCTL(devvp, DIOCGPART, (caddr_t)&dpart,
FREAD, NOCRED, p);
if (error)
goto error_exit;
tmp = dpart.part->p_fstype;
dtype = dpart.disklab->d_type;
bsize = dpart.disklab->d_secsize;
if (bsize != 512 || (dtype!=DTYPE_FLOPPY && tmp!=FS_MSDOS)) {
error = EINVAL;
goto error_exit;
}
}
#endif
/*
* Read the boot sector of the filesystem, and then check the
* boot signature. If not a dos boot sector then error out.
*
* NOTE: 2048 is a maximum sector size in current...
*/
error = bread(devvp, 0, 2048, 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.bsPBP;
#ifndef __FreeBSD__
if (!(argp->flags & MSDOSFSMNT_GEMDOSFS)) {
#endif
#ifndef MSDOSFS_NOCHECKSIG
if (bsp->bs50.bsBootSectSig0 != BOOTSIG0
|| bsp->bs50.bsBootSectSig1 != BOOTSIG1) {
error = EINVAL;
goto error_exit;
}
#endif
#ifndef __FreeBSD__
}
#endif
pmp = malloc(sizeof *pmp, M_MSDOSFSMNT, M_WAITOK | M_ZERO);
pmp->pm_mountp = mp;
/*
* 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);
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;
#ifndef __FreeBSD__
if (!(argp->flags & MSDOSFSMNT_GEMDOSFS)) {
#endif
/* XXX - We should probably check more values here */
if (!pmp->pm_BytesPerSec || !SecPerClust
|| !pmp->pm_Heads || pmp->pm_Heads > 255
#ifdef PC98
|| !pmp->pm_SecPerTrack || pmp->pm_SecPerTrack > 255) {
#else
|| !pmp->pm_SecPerTrack || pmp->pm_SecPerTrack > 63) {
#endif
error = EINVAL;
goto error_exit;
}
#ifndef __FreeBSD__
}
#endif
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_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;
printf("mountmsdosfs(): disk too big, sorry\n");
goto error_exit;
}
if (pmp->pm_RootDirEnts == 0) {
if (bsp->bs710.bsBootSectSig2 != BOOTSIG2
|| bsp->bs710.bsBootSectSig3 != BOOTSIG3
|| pmp->pm_Sectors
|| pmp->pm_FATsecs
|| getushort(b710->bpbFSVers)) {
error = EINVAL;
printf("mountmsdosfs(): bad FAT32 filesystem\n");
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
*/
if ( (SecPerClust == 0)
|| (SecPerClust & (SecPerClust - 1))
|| (pmp->pm_BytesPerSec < DEV_BSIZE)
|| (pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1))
|| (pmp->pm_HugeSectors == 0)
) {
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? */
#ifndef __FreeBSD__
if (argp->flags & MSDOSFSMNT_GEMDOSFS) {
if ((pmp->pm_maxcluster <= (0xff0 - 2))
&& ((dtype == DTYPE_FLOPPY) || ((dtype == DTYPE_VNODE)
&& ((pmp->pm_Heads == 1) || (pmp->pm_Heads == 2))))
) {
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;
}
} else
#endif
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) {
printf("Warning: number of clusters (%ld) exceeds FAT "
"capacity (%ld)\n", pmp->pm_maxcluster + 1, clusters);
pmp->pm_maxcluster = clusters - 1;
}
if (FAT12(pmp))
pmp->pm_fatblocksize = 3 * pmp->pm_BytesPerSec;
else
pmp->pm_fatblocksize = MSDOSFS_DFLTBSIZE;
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 FSInfo.
*/
if (pmp->pm_fsinfo) {
struct fsinfo *fp;
if ((error = bread(devvp, pmp->pm_fsinfo, fsi_size(pmp),
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)
&& !bcmp(fp->fsisig4, "\0\0\125\252", 4))
pmp->pm_nxtfree = getulong(fp->fsinxtfree);
else
pmp->pm_fsinfo = 0;
brelse(bp);
bp = NULL;
}
/*
* Check and validate (or perhaps invalidate?) the fsinfo structure? XXX
*/
/*
* Allocate memory for the bitmap of allocated clusters, and then
* fill it in.
*/
pmp->pm_inusemap = malloc(((pmp->pm_maxcluster + N_INUSEBITS - 1)
/ N_INUSEBITS)
* sizeof(*pmp->pm_inusemap),
M_MSDOSFSFAT, M_WAITOK);
/*
* fillinusemap() needs pm_devvp.
*/
pmp->pm_dev = dev;
pmp->pm_devvp = devvp;
/*
* Have the inuse map filled in.
*/
if ((error = fillinusemap(pmp)) != 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
pmp->pm_fmod = 1;
mp->mnt_data = (qaddr_t) pmp;
mp->mnt_stat.f_fsid.val[0] = dev2udev(dev);
mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum;
mp->mnt_flag |= MNT_LOCAL;
devvp->v_rdev->si_mountpoint = mp;
return 0;
error_exit:
if (bp)
brelse(bp);
(void) VOP_CLOSE(devvp, ronly ? FREAD : FREAD | FWRITE, NOCRED, p);
if (pmp) {
if (pmp->pm_inusemap)
free(pmp->pm_inusemap, M_MSDOSFSFAT);
free(pmp, M_MSDOSFSMNT);
mp->mnt_data = (qaddr_t)0;
}
return (error);
}
/*
* Unmount the filesystem described by mp.
*/
static int
msdosfs_unmount(mp, mntflags, p)
struct mount *mp;
int mntflags;
struct proc *p;
{
struct msdosfsmount *pmp;
int error, flags;
flags = 0;
if (mntflags & MNT_FORCE)
flags |= FORCECLOSE;
error = vflush(mp, NULLVP, flags);
if (error)
return error;
pmp = VFSTOMSDOSFS(mp);
pmp->pm_devvp->v_rdev->si_mountpoint = NULL;
#ifdef MSDOSFS_DEBUG
{
struct vnode *vp = pmp->pm_devvp;
printf("msdosfs_umount(): just before calling VOP_CLOSE()\n");
printf("flag %08lx, usecount %d, writecount %d, holdcnt %ld\n",
vp->v_flag, vp->v_usecount, vp->v_writecount, vp->v_holdcnt);
printf("id %lu, mount %p, op %p\n",
vp->v_id, vp->v_mount, vp->v_op);
printf("freef %p, freeb %p, mount %p\n",
TAILQ_NEXT(vp, v_freelist), vp->v_freelist.tqe_prev,
vp->v_mount);
printf("cleanblkhd %p, dirtyblkhd %p, numoutput %ld, type %d\n",
TAILQ_FIRST(&vp->v_cleanblkhd),
TAILQ_FIRST(&vp->v_dirtyblkhd),
vp->v_numoutput, vp->v_type);
printf("union %p, tag %d, data[0] %08x, data[1] %08x\n",
vp->v_socket, vp->v_tag,
((u_int *)vp->v_data)[0],
((u_int *)vp->v_data)[1]);
}
#endif
error = VOP_CLOSE(pmp->pm_devvp,
(pmp->pm_flags&MSDOSFSMNT_RONLY) ? FREAD : FREAD | FWRITE,
NOCRED, p);
vrele(pmp->pm_devvp);
free(pmp->pm_inusemap, M_MSDOSFSFAT);
free(pmp, M_MSDOSFSMNT);
mp->mnt_data = (qaddr_t)0;
mp->mnt_flag &= ~MNT_LOCAL;
return (error);
}
static int
msdosfs_root(mp, vpp)
struct mount *mp;
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(mp, sbp, p)
struct mount *mp;
struct statfs *sbp;
struct proc *p;
{
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? */
if (sbp != &mp->mnt_stat) {
sbp->f_type = mp->mnt_vfc->vfc_typenum;
bcopy(mp->mnt_stat.f_mntonname, sbp->f_mntonname, MNAMELEN);
bcopy(mp->mnt_stat.f_mntfromname, sbp->f_mntfromname, MNAMELEN);
}
strncpy(sbp->f_fstypename, mp->mnt_vfc->vfc_name, MFSNAMELEN);
return (0);
}
static int
msdosfs_sync(mp, waitfor, cred, p)
struct mount *mp;
int waitfor;
struct ucred *cred;
struct proc *p;
{
struct vnode *vp, *nvp;
struct denode *dep;
struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
int error, allerror = 0;
/*
* 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.
*/
mtx_lock(&mntvnode_mtx);
loop:
for (vp = LIST_FIRST(&mp->mnt_vnodelist); vp != NULL; vp = nvp) {
/*
* If the vnode that we are about to sync is no longer
* associated with this mount point, start over.
*/
if (vp->v_mount != mp)
goto loop;
mtx_lock(&vp->v_interlock);
nvp = LIST_NEXT(vp, v_mntvnodes);
dep = VTODE(vp);
if (vp->v_type == VNON ||
((dep->de_flag &
(DE_ACCESS | DE_CREATE | DE_UPDATE | DE_MODIFIED)) == 0 &&
(TAILQ_EMPTY(&vp->v_dirtyblkhd) || waitfor == MNT_LAZY))) {
mtx_unlock(&vp->v_interlock);
continue;
}
mtx_unlock(&mntvnode_mtx);
error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK, p);
if (error) {
mtx_lock(&mntvnode_mtx);
if (error == ENOENT)
goto loop;
continue;
}
error = VOP_FSYNC(vp, cred, waitfor, p);
if (error)
allerror = error;
VOP_UNLOCK(vp, 0, p);
vrele(vp);
mtx_lock(&mntvnode_mtx);
}
mtx_unlock(&mntvnode_mtx);
/*
* Flush filesystem control info.
*/
if (waitfor != MNT_LAZY) {
vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY, p);
error = VOP_FSYNC(pmp->pm_devvp, cred, waitfor, p);
if (error)
allerror = error;
VOP_UNLOCK(pmp->pm_devvp, 0, p);
}
return (allerror);
}
static int
msdosfs_fhtovp(mp, fhp, vpp)
struct mount *mp;
struct fid *fhp;
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);
return (0);
}
static int
msdosfs_checkexp(mp, nam, exflagsp, credanonp)
struct mount *mp;
struct sockaddr *nam;
int *exflagsp;
struct ucred **credanonp;
{
struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
struct netcred *np;
np = vfs_export_lookup(mp, &pmp->pm_export, nam);
if (np == NULL)
return (EACCES);
*exflagsp = np->netc_exflags;
*credanonp = &np->netc_anon;
return (0);
}
static int
msdosfs_vptofh(vp, fhp)
struct vnode *vp;
struct fid *fhp;
{
struct denode *dep;
struct defid *defhp;
dep = VTODE(vp);
defhp = (struct defid *)fhp;
defhp->defid_len = sizeof(struct defid);
defhp->defid_dirclust = dep->de_dirclust;
defhp->defid_dirofs = dep->de_diroffset;
/* defhp->defid_gen = dep->de_gen; */
return (0);
}
static struct vfsops msdosfs_vfsops = {
msdosfs_mount,
vfs_stdstart,
msdosfs_unmount,
msdosfs_root,
vfs_stdquotactl,
msdosfs_statfs,
msdosfs_sync,
vfs_stdvget,
msdosfs_fhtovp,
msdosfs_checkexp,
msdosfs_vptofh,
msdosfs_init,
msdosfs_uninit,
vfs_stdextattrctl,
};
VFS_SET(msdosfs_vfsops, msdos, 0);
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