NetBSD/sys/msdosfs/msdosfs_vfsops.c
1995-01-18 09:14:37 +00:00

673 lines
18 KiB
C

/* $NetBSD: msdosfs_vfsops.c,v 1.26 1995/01/18 09:14:37 mycroft Exp $ */
/*-
* Copyright (C) 1994 Wolfgang Solfrank.
* Copyright (C) 1994 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/namei.h>
#include <sys/proc.h>
#include <sys/kernel.h>
#include <sys/vnode.h>
#include <miscfs/specfs/specdev.h> /* XXX */ /* defines v_rdev */
#include <sys/mount.h>
#include <sys/buf.h>
#include <sys/file.h>
#include <sys/disklabel.h>
#include <sys/ioctl.h>
#include <sys/malloc.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>
/*
* 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.
*/
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 */
struct msdosfsmount *pmp; /* msdosfs specific mount control block */
u_int size;
int error, flags;
mode_t accessmode;
if (error = copyin(data, (caddr_t)&args, sizeof(struct msdosfs_args)))
return (error);
/*
* 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_ronly == 0 && (mp->mnt_flag & MNT_RDONLY)) {
flags = WRITECLOSE;
if (mp->mnt_flag & MNT_FORCE)
flags |= FORCECLOSE;
if (vfs_busy(mp))
return (EBUSY);
error = vflush(mp, NULLVP, flags);
vfs_unbusy(mp);
}
if (!error && (mp->mnt_flag & MNT_RELOAD))
/* not yet implemented */
error = EOPNOTSUPP;
if (error)
return (error);
if (pmp->pm_ronly && (mp->mnt_flag & MNT_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;
VOP_LOCK(devvp);
if (error = VOP_ACCESS(devvp, VREAD | VWRITE,
p->p_ucred, p)) {
VOP_UNLOCK(devvp);
return (error);
}
VOP_UNLOCK(devvp);
}
pmp->pm_ronly = 0;
}
if (args.fspec == 0) {
/*
* 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);
if (error = namei(ndp))
return (error);
devvp = ndp->ni_vp;
if (devvp->v_type != VBLK) {
vrele(devvp);
return (ENOTBLK);
}
if (major(devvp->v_rdev) >= nblkdev) {
vrele(devvp);
return (ENXIO);
}
/*
* 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;
VOP_LOCK(devvp);
if (error = VOP_ACCESS(devvp, accessmode, p->p_ucred, p)) {
vput(devvp);
return (error);
}
VOP_UNLOCK(devvp);
}
if ((mp->mnt_flag & MNT_UPDATE) == 0)
error = msdosfs_mountfs(devvp, mp, p);
else {
if (devvp != pmp->pm_devvp)
error = EINVAL; /* needs translation */
else
vrele(devvp);
}
if (error) {
vrele(devvp);
return (error);
}
pmp = VFSTOMSDOSFS(mp);
pmp->pm_gid = args.gid;
pmp->pm_uid = args.uid;
pmp->pm_mask = args.mask;
(void) copyinstr(path, mp->mnt_stat.f_mntonname, MNAMELEN - 1, &size);
bzero(mp->mnt_stat.f_mntonname + size, MNAMELEN - size);
(void) copyinstr(args.fspec, mp->mnt_stat.f_mntfromname, MNAMELEN - 1,
&size);
bzero(mp->mnt_stat.f_mntfromname + size, MNAMELEN - size);
#ifdef MSDOSFS_DEBUG
printf("msdosfs_mount(): mp %x, pmp %x, inusemap %x\n", mp, pmp, pmp->pm_inusemap);
#endif
return (0);
}
int
msdosfs_mountfs(devvp, mp, p)
struct vnode *devvp;
struct mount *mp;
struct proc *p;
{
struct msdosfsmount *pmp;
struct buf *bp;
dev_t dev = devvp->v_rdev;
struct partinfo dpart;
union bootsector *bsp;
struct byte_bpb33 *b33;
struct byte_bpb50 *b50;
int bpc;
int bit;
int error, i, size;
int ronly;
extern struct vnode *rootvp;
/*
* 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.
*/
if (error = vfs_mountedon(devvp))
return (error);
if (vcount(devvp) > 1 && devvp != rootvp)
return (EBUSY);
if (error = vinvalbuf(devvp, V_SAVE, p->p_ucred, p, 0, 0))
return (error);
ronly = (mp->mnt_flag & MNT_RDONLY) != 0;
if (error = VOP_OPEN(devvp, ronly ? FREAD : FREAD|FWRITE, FSCRED, p))
return (error);
if (VOP_IOCTL(devvp, DIOCGPART, (caddr_t)&dpart, FREAD, NOCRED, p) != 0)
size = DEV_BSIZE;
else
size = dpart.disklab->d_secsize;
/*
* Read the boot sector of the filesystem, and then check the boot
* signature. If not a dos boot sector then error out. We could
* also add some checking on the bsOemName field. So far I've seen
* the following values: "IBM 3.3" "MSDOS3.3" "MSDOS5.0"
*/
bp = NULL;
pmp = NULL;
if (error = bread(devvp, 0, 512, NOCRED, &bp))
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;
#ifdef MSDOSFS_CHECKSIG
if (bsp->bs50.bsBootSectSig != BOOTSIG) {
error = EINVAL;
goto error_exit;
}
#endif
if ( bsp->bs50.bsJump[0] != 0xe9 &&
(bsp->bs50.bsJump[0] != 0xeb || bsp->bs50.bsJump[2] != 0x90)) {
error = EINVAL;
goto error_exit;
}
pmp = malloc(sizeof *pmp, M_MSDOSFSMNT, M_WAITOK);
bzero((caddr_t)pmp, sizeof *pmp);
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.
*/
pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec);
pmp->pm_SectPerClust = b50->bpbSecPerClust;
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_Media = b50->bpbMedia;
pmp->pm_FATsecs = getushort(b50->bpbFATsecs);
pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack);
pmp->pm_Heads = getushort(b50->bpbHeads);
/* XXX - We should probably check more values here */
if (!pmp->pm_BytesPerSec || !pmp->pm_SectPerClust ||
!pmp->pm_Heads || pmp->pm_Heads > 255 ||
!pmp->pm_SecPerTrack || pmp->pm_SecPerTrack > 63) {
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;
}
pmp->pm_fatblk = pmp->pm_ResSectors;
pmp->pm_rootdirblk = pmp->pm_fatblk +
(pmp->pm_FATs * pmp->pm_FATsecs);
pmp->pm_rootdirsize = (pmp->pm_RootDirEnts * sizeof(struct direntry))
/
pmp->pm_BytesPerSec;/* in sectors */
pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize;
pmp->pm_nmbrofclusters = (pmp->pm_HugeSectors - pmp->pm_firstcluster) /
pmp->pm_SectPerClust;
pmp->pm_maxcluster = pmp->pm_nmbrofclusters + 1;
pmp->pm_fatsize = pmp->pm_FATsecs * pmp->pm_BytesPerSec;
if (FAT12(pmp))
/*
* This will usually be a floppy disk. This size makes sure
* that one fat entry will not be split across multiple
* blocks.
*/
pmp->pm_fatblocksize = 3 * pmp->pm_BytesPerSec;
else
/*
* This will usually be a hard disk. Reading or writing one
* block should be quite fast.
*/
pmp->pm_fatblocksize = MAXBSIZE;
pmp->pm_fatblocksec = pmp->pm_fatblocksize / pmp->pm_BytesPerSec;
if ((pmp->pm_rootdirsize % pmp->pm_SectPerClust) != 0)
printf("mountmsdosfs(): root directory is not a multiple of the clustersize in length\n");
/*
* Compute mask and shift value for isolating cluster relative byte
* offsets and cluster numbers from a file offset.
*/
bpc = pmp->pm_SectPerClust * pmp->pm_BytesPerSec;
pmp->pm_bpcluster = bpc;
pmp->pm_depclust = bpc / sizeof(struct direntry);
pmp->pm_crbomask = bpc - 1;
if (bpc == 0) {
error = EINVAL;
goto error_exit;
}
bit = 1;
for (i = 0; i < 32; i++) {
if (bit & bpc) {
if (bit ^ bpc) {
error = EINVAL;
goto error_exit;
}
pmp->pm_cnshift = i;
break;
}
bit <<= 1;
}
pmp->pm_brbomask = 0x01ff; /* 512 byte blocks only (so far) */
pmp->pm_bnshift = 9; /* shift right 9 bits to get bn */
/*
* Release the bootsector buffer.
*/
brelse(bp);
bp = NULL;
/*
* 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))
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.
*/
pmp->pm_waitonfat = mp->mnt_flag & MNT_SYNCHRONOUS;
/*
* Finish up.
*/
pmp->pm_ronly = ronly;
if (ronly == 0)
pmp->pm_fmod = 1;
mp->mnt_data = (qaddr_t)pmp;
mp->mnt_stat.f_fsid.val[0] = (long)dev;
mp->mnt_stat.f_fsid.val[1] = makefstype(MOUNT_MSDOS);
mp->mnt_flag |= MNT_LOCAL;
#ifdef QUOTA
/*
* If we ever do quotas for DOS filesystems this would be a place
* to fill in the info in the msdosfsmount structure. You dolt,
* quotas on dos filesystems make no sense because files have no
* owners on dos filesystems. of course there is some empty space
* in the directory entry where we could put uid's and gid's.
*/
#endif
devvp->v_specflags |= SI_MOUNTEDON;
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);
}
int
msdosfs_start(mp, flags, p)
struct mount *mp;
int flags;
struct proc *p;
{
return (0);
}
/*
* Unmount the filesystem described by mp.
*/
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;
#ifdef QUOTA
#endif
if (error = vflush(mp, NULLVP, flags))
return (error);
pmp = VFSTOMSDOSFS(mp);
pmp->pm_devvp->v_specflags &= ~SI_MOUNTEDON;
#ifdef MSDOSFS_DEBUG
printf("msdosfs_umount(): just before calling VOP_CLOSE()\n");
printf("flag %08x, usecount %d, writecount %d, holdcnt %d\n",
vp->v_flag, vp->v_usecount, vp->v_writecount, vp->v_holdcnt);
printf("lastr %d, id %d, mount %08x, op %08x\n",
vp->v_lastr, vp->v_id, vp->v_mount, vp->v_op);
printf("freef %08x, freeb %08x, mountf %08x, mountb %08x\n",
vp->v_freef, vp->v_freeb, vp->v_mountf, vp->v_mountb);
printf("cleanblkhd %08x, dirtyblkhd %08x, numoutput %d, type %d\n",
vp->v_cleanblkhd, vp->v_dirtyblkhd, vp->v_numoutput, vp->v_type);
printf("union %08x, tag %d, data[0] %08x, data[1] %08x\n",
vp->v_socket, vp->v_tag, vp->v_data[0], vp->v_data[1]);
#endif
error = VOP_CLOSE(pmp->pm_devvp, pmp->pm_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);
}
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 %08x, pmp %08x, ndep %08x, vp %08x\n",
mp, pmp, ndep, DETOV(ndep));
#endif
if (error = deget(pmp, MSDOSFSROOT, MSDOSFSROOT_OFS, NULL, &ndep))
return (error);
*vpp = DETOV(ndep);
return (0);
}
int
msdosfs_quotactl(mp, cmds, uid, arg, p)
struct mount *mp;
int cmds;
uid_t uid;
caddr_t arg;
struct proc *p;
{
#ifdef QUOTA
return (EOPNOTSUPP);
#else
return (EOPNOTSUPP);
#endif
}
int
msdosfs_statfs(mp, sbp, p)
struct mount *mp;
struct statfs *sbp;
struct proc *p;
{
struct msdosfsmount *pmp;
pmp = VFSTOMSDOSFS(mp);
#ifdef COMPAT_09
sbp->f_type = 4;
#else
sbp->f_type = 0;
#endif
sbp->f_bsize = pmp->pm_bpcluster;
sbp->f_iosize = pmp->pm_bpcluster;
sbp->f_blocks = pmp->pm_nmbrofclusters;
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) {
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_op->vfs_name, MFSNAMELEN);
sbp->f_fstypename[MFSNAMELEN] = '\0';
return (0);
}
int
msdosfs_sync(mp, waitfor, cred, p)
struct mount *mp;
int waitfor;
struct ucred *cred;
struct proc *p;
{
struct vnode *vp;
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_ronly != 0)
panic("msdosfs_sync: rofs mod");
else {
/* update fats here */
}
/*
* Write back each (modified) denode.
*/
loop:
for (vp = mp->mnt_vnodelist.lh_first;
vp != NULL;
vp = vp->v_mntvnodes.le_next) {
/*
* If the vnode that we are about to sync is no longer
* assoicated with this mount point, start over.
*/
if (vp->v_mount != mp)
goto loop;
if (VOP_ISLOCKED(vp))
continue;
dep = VTODE(vp);
if ((dep->de_flag & DE_UPDATE) == 0 &&
vp->v_dirtyblkhd.lh_first == NULL)
continue;
if (vget(vp, 1))
goto loop;
if (error = VOP_FSYNC(vp, cred, waitfor, p))
allerror = error;
vput(vp);
}
/*
* Force stale file system control information to be flushed.
*/
if (error = VOP_FSYNC(pmp->pm_devvp, cred, waitfor, p))
allerror = error;
#ifdef QUOTA
#endif
return (allerror);
}
int
msdosfs_fhtovp(mp, fhp, nam, vpp, exflagsp, credanonp)
struct mount *mp;
struct fid *fhp;
struct mbuf *nam;
struct vnode **vpp;
int *exflagsp;
struct ucred **credanonp;
{
struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
struct defid *defhp = (struct defid *) fhp;
struct denode *dep;
struct netcred *np;
int error;
np = vfs_export_lookup(mp, &pmp->pm_export, nam);
if (np == NULL)
return (EACCES);
error = deget(pmp, defhp->defid_dirclust, defhp->defid_dirofs,
NULL, &dep);
if (error) {
*vpp = NULLVP;
return (error);
}
*vpp = DETOV(dep);
*exflagsp = np->netc_exflags;
*credanonp = &np->netc_anon;
return (0);
}
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);
}
int
msdosfs_vget(mp, ino, vpp)
struct mount *mp;
ino_t ino;
struct vnode **vpp;
{
return (EOPNOTSUPP);
}
struct vfsops msdosfs_vfsops = {
MOUNT_MSDOS,
msdosfs_mount,
msdosfs_start,
msdosfs_unmount,
msdosfs_root,
msdosfs_quotactl,
msdosfs_statfs,
msdosfs_sync,
msdosfs_vget,
msdosfs_fhtovp,
msdosfs_vptofh,
msdosfs_init
};