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freebsd-skq/sys/msdosfs/msdosfs_vnops.c
John Dyson 39b1a97c77 MSDOS FS used to allocate a buffer before extending the VM object. In 
certain error conditions, it is possible for pages to be left allocated
in the object beyond it's end.  It is generally bad practice to allocate
pages beyond the end of an object.
1996-10-02 05:01:17 +00:00

2056 lines
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/* $Id: msdosfs_vnops.c,v 1.33 1996/09/19 18:20:47 nate Exp $ */
/* $NetBSD: msdosfs_vnops.c,v 1.20 1994/08/21 18:44:13 ws 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/resourcevar.h> /* defines plimit structure in proc struct */
#include <sys/kernel.h>
#include <sys/stat.h>
#include <sys/buf.h>
#include <sys/proc.h>
#include <sys/mount.h>
#include <sys/unistd.h>
#include <sys/vnode.h>
#include <miscfs/specfs/specdev.h> /* XXX */ /* defines v_rdev */
#include <sys/malloc.h>
#include <sys/dir.h> /* defines dirent structure */
#include <sys/signalvar.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/vm_extern.h>
#include <msdosfs/bpb.h>
#include <msdosfs/direntry.h>
#include <msdosfs/denode.h>
#include <msdosfs/msdosfsmount.h>
#include <msdosfs/fat.h>
/*
* Prototypes for MSDOSFS vnode operations
*/
static int msdosfs_create __P((struct vop_create_args *));
static int msdosfs_mknod __P((struct vop_mknod_args *));
static int msdosfs_open __P((struct vop_open_args *));
static int msdosfs_close __P((struct vop_close_args *));
static int msdosfs_access __P((struct vop_access_args *));
static int msdosfs_getattr __P((struct vop_getattr_args *));
static int msdosfs_setattr __P((struct vop_setattr_args *));
static int msdosfs_read __P((struct vop_read_args *));
static int msdosfs_write __P((struct vop_write_args *));
static int msdosfs_ioctl __P((struct vop_ioctl_args *));
static int msdosfs_select __P((struct vop_select_args *));
static int msdosfs_mmap __P((struct vop_mmap_args *));
static int msdosfs_fsync __P((struct vop_fsync_args *));
static int msdosfs_seek __P((struct vop_seek_args *));
static int msdosfs_remove __P((struct vop_remove_args *));
static int msdosfs_link __P((struct vop_link_args *));
static int msdosfs_rename __P((struct vop_rename_args *));
static int msdosfs_mkdir __P((struct vop_mkdir_args *));
static int msdosfs_rmdir __P((struct vop_rmdir_args *));
static int msdosfs_symlink __P((struct vop_symlink_args *));
static int msdosfs_readdir __P((struct vop_readdir_args *));
static int msdosfs_readlink __P((struct vop_readlink_args *));
static int msdosfs_abortop __P((struct vop_abortop_args *));
static int msdosfs_lock __P((struct vop_lock_args *));
static int msdosfs_unlock __P((struct vop_unlock_args *));
static int msdosfs_bmap __P((struct vop_bmap_args *));
static int msdosfs_strategy __P((struct vop_strategy_args *));
static int msdosfs_print __P((struct vop_print_args *));
static int msdosfs_islocked __P((struct vop_islocked_args *));
static int msdosfs_advlock __P((struct vop_advlock_args *));
static int msdosfs_pathconf __P((struct vop_pathconf_args *ap));
static int msdosfs_reallocblks __P((struct vop_reallocblks_args *));
/*
* Some general notes:
*
* In the ufs filesystem the inodes, superblocks, and indirect blocks are
* read/written using the vnode for the filesystem. Blocks that represent
* the contents of a file are read/written using the vnode for the file
* (including directories when they are read/written as files). This
* presents problems for the dos filesystem because data that should be in
* an inode (if dos had them) resides in the directory itself. Since we
* must update directory entries without the benefit of having the vnode
* for the directory we must use the vnode for the filesystem. This means
* that when a directory is actually read/written (via read, write, or
* readdir, or seek) we must use the vnode for the filesystem instead of
* the vnode for the directory as would happen in ufs. This is to insure we
* retreive the correct block from the buffer cache since the hash value is
* based upon the vnode address and the desired block number.
*/
/*
* Create a regular file. On entry the directory to contain the file being
* created is locked. We must release before we return. We must also free
* the pathname buffer pointed at by cnp->cn_pnbuf, always on error, or
* only if the SAVESTART bit in cn_flags is clear on success.
*/
static int
msdosfs_create(ap)
struct vop_create_args /* {
struct vnode *a_dvp;
struct vnode **a_vpp;
struct componentname *a_cnp;
struct vattr *a_vap;
} */ *ap;
{
struct componentname *cnp = ap->a_cnp;
struct denode ndirent;
struct denode *dep;
struct denode *pdep = VTODE(ap->a_dvp);
struct timespec ts;
int error;
#ifdef MSDOSFS_DEBUG
printf("msdosfs_create(cnp %08x, vap %08x\n", cnp, ap->a_vap);
#endif
/*
* Create a directory entry for the file, then call createde() to
* have it installed. NOTE: DOS files are always executable. We
* use the absence of the owner write bit to make the file
* readonly.
*/
#ifdef DIAGNOSTIC
if ((cnp->cn_flags & SAVENAME) == 0)
panic("msdosfs_create: no name");
#endif
bzero(&ndirent, sizeof(ndirent));
TIMEVAL_TO_TIMESPEC(&time, &ts);
unix2dostime(&ts, &ndirent.de_Date, &ndirent.de_Time);
unix2dosfn((u_char *)cnp->cn_nameptr, ndirent.de_Name, cnp->cn_namelen);
ndirent.de_Attributes = (ap->a_vap->va_mode & VWRITE)
? ATTR_ARCHIVE : ATTR_ARCHIVE | ATTR_READONLY;
ndirent.de_StartCluster = 0;
ndirent.de_FileSize = 0;
ndirent.de_dev = pdep->de_dev;
ndirent.de_devvp = pdep->de_devvp;
if ((error = createde(&ndirent, pdep, &dep)) == 0) {
*ap->a_vpp = DETOV(dep);
if ((cnp->cn_flags & SAVESTART) == 0)
free(cnp->cn_pnbuf, M_NAMEI);
} else {
free(cnp->cn_pnbuf, M_NAMEI);
}
vput(ap->a_dvp); /* release parent dir */
return error;
}
static int
msdosfs_mknod(ap)
struct vop_mknod_args /* {
struct vnode *a_dvp;
struct vnode **a_vpp;
struct componentname *a_cnp;
struct vattr *a_vap;
} */ *ap;
{
int error;
switch (ap->a_vap->va_type) {
case VDIR:
error = msdosfs_mkdir((struct vop_mkdir_args *)ap);
break;
case VREG:
error = msdosfs_create((struct vop_create_args *)ap);
break;
default:
error = EINVAL;
free(ap->a_cnp->cn_pnbuf, M_NAMEI);
vput(ap->a_dvp);
break;
}
return error;
}
static int
msdosfs_open(ap)
struct vop_open_args /* {
struct vnode *a_vp;
int a_mode;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
return 0;
}
static int
msdosfs_close(ap)
struct vop_close_args /* {
struct vnode *a_vp;
int a_fflag;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
struct vnode *vp = ap->a_vp;
struct denode *dep = VTODE(vp);
if (vp->v_usecount > 1 && !(dep->de_flag & DE_LOCKED))
DE_TIMES(dep, &time);
return 0;
}
static int
msdosfs_access(ap)
struct vop_access_args /* {
struct vnode *a_vp;
int a_mode;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
struct vnode *vp = ap->a_vp;
struct denode *dep = VTODE(ap->a_vp);
struct msdosfsmount *pmp = dep->de_pmp;
struct ucred *cred = ap->a_cred;
mode_t mask, file_mode, mode = ap->a_mode;
register gid_t *gp;
int i;
file_mode = (S_IXUSR|S_IXGRP|S_IXOTH) | (S_IRUSR|S_IRGRP|S_IROTH) |
((dep->de_Attributes & ATTR_READONLY) ? 0 : (S_IWUSR|S_IWGRP|S_IWOTH));
file_mode &= pmp->pm_mask;
/*
* Disallow write attempts on read-only file systems;
* unless the file is a socket, fifo, or a block or
* character device resident on the file system.
*/
if (mode & VWRITE) {
switch (vp->v_type) {
case VDIR:
case VLNK:
case VREG:
if (vp->v_mount->mnt_flag & MNT_RDONLY)
return (EROFS);
break;
}
}
/* User id 0 always gets access. */
if (cred->cr_uid == 0)
return 0;
mask = 0;
/* Otherwise, check the owner. */
if (cred->cr_uid == pmp->pm_uid) {
if (mode & VEXEC)
mask |= S_IXUSR;
if (mode & VREAD)
mask |= S_IRUSR;
if (mode & VWRITE)
mask |= S_IWUSR;
return (file_mode & mask) == mask ? 0 : EACCES;
}
/* Otherwise, check the groups. */
for (i = 0, gp = cred->cr_groups; i < cred->cr_ngroups; i++, gp++)
if (pmp->pm_gid == *gp) {
if (mode & VEXEC)
mask |= S_IXGRP;
if (mode & VREAD)
mask |= S_IRGRP;
if (mode & VWRITE)
mask |= S_IWGRP;
return (file_mode & mask) == mask ? 0 : EACCES;
}
/* Otherwise, check everyone else. */
if (mode & VEXEC)
mask |= S_IXOTH;
if (mode & VREAD)
mask |= S_IROTH;
if (mode & VWRITE)
mask |= S_IWOTH;
return (file_mode & mask) == mask ? 0 : EACCES;
}
static int
msdosfs_getattr(ap)
struct vop_getattr_args /* {
struct vnode *a_vp;
struct vattr *a_vap;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
u_int cn;
struct denode *dep = VTODE(ap->a_vp);
struct vattr *vap = ap->a_vap;
DE_TIMES(dep, &time);
vap->va_fsid = dep->de_dev;
/*
* The following computation of the fileid must be the same as that
* used in msdosfs_readdir() to compute d_fileno. If not, pwd
* doesn't work.
*/
if (dep->de_Attributes & ATTR_DIRECTORY) {
if ((cn = dep->de_StartCluster) == MSDOSFSROOT)
cn = 1;
} else {
if ((cn = dep->de_dirclust) == MSDOSFSROOT)
cn = 1;
cn = (cn << 16) | (dep->de_diroffset & 0xffff);
}
vap->va_fileid = cn;
vap->va_mode = (S_IXUSR|S_IXGRP|S_IXOTH) | (S_IRUSR|S_IRGRP|S_IROTH) |
((dep->de_Attributes & ATTR_READONLY) ? 0 : (S_IWUSR|S_IWGRP|S_IWOTH));
vap->va_mode &= dep->de_pmp->pm_mask;
if (dep->de_Attributes & ATTR_DIRECTORY)
vap->va_mode |= S_IFDIR;
vap->va_nlink = 1;
vap->va_gid = dep->de_pmp->pm_gid;
vap->va_uid = dep->de_pmp->pm_uid;
vap->va_rdev = 0;
vap->va_size = dep->de_FileSize;
dos2unixtime(dep->de_Date, dep->de_Time, &vap->va_atime);
vap->va_mtime = vap->va_atime;
#if 0
#ifndef MSDOSFS_NODIRMOD
if (vap->va_mode & S_IFDIR)
TIMEVAL_TO_TIMESPEC(&time, &vap->va_mtime);
#endif
#endif
vap->va_ctime = vap->va_atime;
vap->va_flags = (dep->de_Attributes & ATTR_ARCHIVE) ? 0 : SF_ARCHIVED;
vap->va_gen = 0;
vap->va_blocksize = dep->de_pmp->pm_bpcluster;
vap->va_bytes = (dep->de_FileSize + dep->de_pmp->pm_crbomask) &
~(dep->de_pmp->pm_crbomask);
vap->va_type = ap->a_vp->v_type;
vap->va_filerev = dep->de_modrev;
return 0;
}
static int
msdosfs_setattr(ap)
struct vop_setattr_args /* {
struct vnode *a_vp;
struct vattr *a_vap;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
struct vnode *vp = ap->a_vp;
struct denode *dep = VTODE(ap->a_vp);
struct vattr *vap = ap->a_vap;
struct ucred *cred = ap->a_cred;
int error = 0;
/*
* Check for unsettable attributes.
*/
if ((vap->va_type != VNON) || (vap->va_nlink != VNOVAL) ||
(vap->va_fsid != VNOVAL) || (vap->va_fileid != VNOVAL) ||
(vap->va_blocksize != VNOVAL) || (vap->va_rdev != VNOVAL) ||
(vap->va_bytes != VNOVAL) || (vap->va_gen != VNOVAL)) {
return (EINVAL);
}
if (vap->va_flags != VNOVAL) {
if (vp->v_mount->mnt_flag & MNT_RDONLY)
return (EROFS);
if (cred->cr_uid != dep->de_pmp->pm_uid &&
(error = suser(cred, &ap->a_p->p_acflag)))
return (error);
/*
* We are very inconsistent about handling unsupported
* attributes. We ignored the the access time and the
* read and execute bits. We were strict for the other
* attributes.
*
* Here we are strict, stricter than ufs in not allowing
* users to attempt to set SF_SETTABLE bits or anyone to
* set unsupported bits. However, we ignore attempts to
* set ATTR_ARCHIVE for directories `cp -pr' from a more
* sensible file system attempts it a lot.
*/
if (cred->cr_uid != 0) {
if (vap->va_flags & SF_SETTABLE)
return EPERM;
}
if (vap->va_flags & ~SF_ARCHIVED)
return EINVAL;
if (vap->va_flags & SF_ARCHIVED)
dep->de_Attributes &= ~ATTR_ARCHIVE;
else if (!(dep->de_Attributes & ATTR_DIRECTORY))
dep->de_Attributes |= ATTR_ARCHIVE;
dep->de_flag |= DE_MODIFIED;
}
if (vap->va_uid != (uid_t)VNOVAL || vap->va_gid != (uid_t)VNOVAL) {
if (vp->v_mount->mnt_flag & MNT_RDONLY)
return (EROFS);
if ((cred->cr_uid != dep->de_pmp->pm_uid ||
vap->va_uid != dep->de_pmp->pm_uid ||
(vap->va_gid != dep->de_pmp->pm_gid &&
!groupmember(vap->va_gid, cred))) &&
(error = suser(cred, &ap->a_p->p_acflag)))
return error;
if (vap->va_uid != dep->de_pmp->pm_uid ||
vap->va_gid != dep->de_pmp->pm_gid)
return EINVAL;
}
if (vap->va_size != VNOVAL) {
/*
* Disallow write attempts on read-only file systems;
* unless the file is a socket, fifo, or a block or
* character device resident on the file system.
*/
switch (vp->v_type) {
case VDIR:
return (EISDIR);
case VLNK:
case VREG:
if (vp->v_mount->mnt_flag & MNT_RDONLY)
return (EROFS);
break;
}
error = detrunc(dep, vap->va_size, 0, cred, ap->a_p);
if (error)
return error;
}
if (vap->va_mtime.tv_sec != VNOVAL) {
if (vp->v_mount->mnt_flag & MNT_RDONLY)
return (EROFS);
if (cred->cr_uid != dep->de_pmp->pm_uid &&
(error = suser(cred, &ap->a_p->p_acflag)) &&
((vap->va_vaflags & VA_UTIMES_NULL) == 0 ||
(error = VOP_ACCESS(vp, VWRITE, cred, ap->a_p))))
return error;
dep->de_flag |= DE_UPDATE;
error = deupdat(dep, &vap->va_mtime, 1);
if (error)
return error;
}
/*
* DOS files only have the ability to have their writability
* attribute set, so we use the owner write bit to set the readonly
* attribute.
*/
error = 0;
if (vap->va_mode != (u_short) VNOVAL) {
if (vp->v_mount->mnt_flag & MNT_RDONLY)
return (EROFS);
if (cred->cr_uid != dep->de_pmp->pm_uid &&
(error = suser(cred, &ap->a_p->p_acflag)))
return error;
/* We ignore the read and execute bits */
if (vap->va_mode & VWRITE)
dep->de_Attributes &= ~ATTR_READONLY;
else
dep->de_Attributes |= ATTR_READONLY;
dep->de_flag |= DE_MODIFIED;
}
return error;
}
static int
msdosfs_read(ap)
struct vop_read_args /* {
struct vnode *a_vp;
struct uio *a_uio;
int a_ioflag;
struct ucred *a_cred;
} */ *ap;
{
int error = 0;
int diff;
int isadir;
long n;
long on;
daddr_t lbn;
daddr_t rablock;
int rasize;
struct buf *bp;
struct vnode *vp = ap->a_vp;
struct denode *dep = VTODE(vp);
struct msdosfsmount *pmp = dep->de_pmp;
struct uio *uio = ap->a_uio;
/*
* If they didn't ask for any data, then we are done.
*/
if (uio->uio_resid == 0)
return 0;
if (uio->uio_offset < 0)
return EINVAL;
isadir = dep->de_Attributes & ATTR_DIRECTORY;
do {
lbn = uio->uio_offset >> pmp->pm_cnshift;
on = uio->uio_offset & pmp->pm_crbomask;
n = min((u_long) (pmp->pm_bpcluster - on), uio->uio_resid);
diff = dep->de_FileSize - uio->uio_offset;
if (diff <= 0)
return 0;
/* convert cluster # to block # if a directory */
if (isadir) {
error = pcbmap(dep, lbn, &lbn, 0);
if (error)
return error;
}
if (diff < n)
n = diff;
/*
* If we are operating on a directory file then be sure to
* do i/o with the vnode for the filesystem instead of the
* vnode for the directory.
*/
if (isadir) {
error = bread(pmp->pm_devvp, lbn, pmp->pm_bpcluster,
NOCRED, &bp);
} else {
rablock = lbn + 1;
#ifdef PC98
/*
* 1024byte/sector support
*/
if (pmp->pm_BytesPerSec == 1024)
vp->v_flag |= 0x10000;
#endif
if (vp->v_lastr + 1 == lbn &&
rablock * pmp->pm_bpcluster < dep->de_FileSize) {
rasize = pmp->pm_bpcluster;
error = breadn(vp, lbn, pmp->pm_bpcluster,
&rablock, &rasize, 1,
NOCRED, &bp);
} else {
error = bread(vp, lbn, pmp->pm_bpcluster, NOCRED,
&bp);
}
vp->v_lastr = lbn;
}
n = min(n, pmp->pm_bpcluster - bp->b_resid);
if (error) {
brelse(bp);
return error;
}
error = uiomove(bp->b_data + on, (int) n, uio);
/*
* If we have read everything from this block or have read
* to end of file then we are done with this block. Mark
* it to say the buffer can be reused if need be.
*/
#if 0
if (n + on == pmp->pm_bpcluster ||
uio->uio_offset == dep->de_FileSize)
bp->b_flags |= B_AGE;
#endif
brelse(bp);
} while (error == 0 && uio->uio_resid > 0 && n != 0);
return error;
}
/*
* Write data to a file or directory.
*/
static int
msdosfs_write(ap)
struct vop_write_args /* {
struct vnode *a_vp;
struct uio *a_uio;
int a_ioflag;
struct ucred *a_cred;
} */ *ap;
{
int n;
int isadir;
int croffset;
int resid;
int osize;
int error = 0;
u_long count;
daddr_t bn, lastcn;
struct buf *bp;
int ioflag = ap->a_ioflag;
struct uio *uio = ap->a_uio;
struct proc *p = uio->uio_procp;
struct vnode *vp = ap->a_vp;
struct vnode *thisvp;
struct denode *dep = VTODE(vp);
struct msdosfsmount *pmp = dep->de_pmp;
struct ucred *cred = ap->a_cred;
struct timespec ts;
#ifdef MSDOSFS_DEBUG
printf("msdosfs_write(vp %08x, uio %08x, ioflag %08x, cred %08x\n",
vp, uio, ioflag, cred);
printf("msdosfs_write(): diroff %d, dirclust %d, startcluster %d\n",
dep->de_diroffset, dep->de_dirclust, dep->de_StartCluster);
#endif
switch (vp->v_type) {
case VREG:
if (ioflag & IO_APPEND)
uio->uio_offset = dep->de_FileSize;
isadir = 0;
thisvp = vp;
break;
case VDIR:
if ((ioflag & IO_SYNC) == 0)
panic("msdosfs_write(): non-sync directory update");
isadir = 1;
thisvp = pmp->pm_devvp;
break;
default:
panic("msdosfs_write(): bad file type");
break;
}
if (uio->uio_offset < 0)
return EINVAL;
if (uio->uio_resid == 0)
return 0;
/*
* If they've exceeded their filesize limit, tell them about it.
*/
if (vp->v_type == VREG && p &&
((uio->uio_offset + uio->uio_resid) >
p->p_rlimit[RLIMIT_FSIZE].rlim_cur)) {
psignal(p, SIGXFSZ);
return EFBIG;
}
/*
* If attempting to write beyond the end of the root directory we
* stop that here because the root directory can not grow.
*/
if ((dep->de_Attributes & ATTR_DIRECTORY) &&
dep->de_StartCluster == MSDOSFSROOT &&
(uio->uio_offset + uio->uio_resid) > dep->de_FileSize)
return ENOSPC;
/*
* If the offset we are starting the write at is beyond the end of
* the file, then they've done a seek. Unix filesystems allow
* files with holes in them, DOS doesn't so we must fill the hole
* with zeroed blocks.
*/
if (uio->uio_offset > dep->de_FileSize) {
error = deextend(dep, uio->uio_offset, cred);
if (error)
return error;
}
/*
* Remember some values in case the write fails.
*/
resid = uio->uio_resid;
osize = dep->de_FileSize;
#ifdef PC98
/*
* 1024byte/sector support
*/
if (pmp->pm_BytesPerSec == 1024)
thisvp->v_flag |= 0x10000;
#endif
/*
* If we write beyond the end of the file, extend it to its ultimate
* size ahead of the time to hopefully get a contiguous area.
*/
if (uio->uio_offset + resid > osize) {
count = de_clcount(pmp, uio->uio_offset + resid) - de_clcount(pmp, osize);
if ((error = extendfile(dep, count, NULL, NULL, 0))
&& (error != ENOSPC || (ioflag & IO_UNIT)))
goto errexit;
lastcn = dep->de_fc[FC_LASTFC].fc_frcn;
} else
lastcn = de_clcount(pmp, osize) - 1;
do {
bn = de_blk(pmp, uio->uio_offset);
if (isadir) {
error = pcbmap(dep, bn, &bn, 0);
if (error)
break;
} else if (bn > lastcn) {
error = ENOSPC;
break;
}
croffset = uio->uio_offset & pmp->pm_crbomask;
n = min(uio->uio_resid, pmp->pm_bpcluster - croffset);
if (uio->uio_offset + n > dep->de_FileSize) {
dep->de_FileSize = uio->uio_offset + n;
/* The object size needs to be set before buffer is allocated */
vnode_pager_setsize(vp, dep->de_FileSize);
}
if ((uio->uio_offset & pmp->pm_crbomask) == 0
&& (de_blk(pmp, uio->uio_offset + uio->uio_resid) > de_blk(pmp, uio->uio_offset)
|| uio->uio_offset + uio->uio_resid >= dep->de_FileSize)) {
/*
* If either the whole cluster gets written,
* or we write the cluster from its start beyond EOF,
* then no need to read data from disk.
*/
bp = getblk(thisvp, bn, pmp->pm_bpcluster, 0, 0);
clrbuf(bp);
/*
* Do the bmap now, since pcbmap needs buffers
* for the fat table. (see msdosfs_strategy)
*/
if (!isadir) {
if (bp->b_blkno == bp->b_lblkno) {
error = pcbmap(dep, bp->b_lblkno,
&bp->b_blkno, 0);
if (error)
bp->b_blkno = -1;
}
if (bp->b_blkno == -1) {
brelse(bp);
if (!error)
error = EIO; /* XXX */
break;
}
}
} else {
/*
* The block we need to write into exists, so read it in.
*/
error = bread(thisvp, bn, pmp->pm_bpcluster, cred, &bp);
if (error)
break;
}
/*
* Should these vnode_pager_* functions be done on dir
* files?
*/
/*
* Copy the data from user space into the buf header.
*/
error = uiomove(bp->b_data + croffset, n, uio);
/*
* If they want this synchronous then write it and wait for
* it. Otherwise, if on a cluster boundary write it
* asynchronously so we can move on to the next block
* without delay. Otherwise do a delayed write because we
* may want to write somemore into the block later.
*/
if (ioflag & IO_SYNC)
(void) bwrite(bp);
else if (n + croffset == pmp->pm_bpcluster) {
bawrite(bp);
} else
bdwrite(bp);
dep->de_flag |= DE_UPDATE;
} while (error == 0 && uio->uio_resid > 0);
/*
* If the write failed and they want us to, truncate the file back
* to the size it was before the write was attempted.
*/
errexit:
if (error) {
if (ioflag & IO_UNIT) {
detrunc(dep, osize, ioflag & IO_SYNC, NOCRED, NULL);
uio->uio_offset -= resid - uio->uio_resid;
uio->uio_resid = resid;
} else {
detrunc(dep, dep->de_FileSize, ioflag & IO_SYNC, NOCRED, NULL);
if (uio->uio_resid != resid)
error = 0;
}
} else {
TIMEVAL_TO_TIMESPEC(&time, &ts);
error = deupdat(dep, &ts, 1);
}
return error;
}
static int
msdosfs_ioctl(ap)
struct vop_ioctl_args /* {
struct vnode *a_vp;
int a_command;
caddr_t a_data;
int a_fflag;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
return ENOTTY;
}
static int
msdosfs_select(ap)
struct vop_select_args /* {
struct vnode *a_vp;
int a_which;
int a_fflags;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
return 1; /* DOS filesystems never block? */
}
static int
msdosfs_mmap(ap)
struct vop_mmap_args /* {
struct vnode *a_vp;
int a_fflags;
struct ucred *a_cred;
struct proc *a_p;
} */ *ap;
{
return EINVAL;
}
/*
* Flush the blocks of a file to disk.
*
* This function is worthless for vnodes that represent directories. Maybe we
* could just do a sync if they try an fsync on a directory file.
*/
static int
msdosfs_fsync(ap)
struct vop_fsync_args /* {
struct vnode *a_vp;
struct ucred *a_cred;
int a_waitfor;
struct proc *a_p;
} */ *ap;
{
register struct vnode *vp = ap->a_vp;
register struct buf *bp;
int wait = ap->a_waitfor == MNT_WAIT;
struct timespec ts;
struct buf *nbp;
int s;
/*
* Flush all dirty buffers associated with a vnode.
*/
loop:
s = splbio();
for (bp = vp->v_dirtyblkhd.lh_first; bp; bp = nbp) {
nbp = bp->b_vnbufs.le_next;
if ((bp->b_flags & B_BUSY))
continue;
if ((bp->b_flags & B_DELWRI) == 0)
panic("msdosfs_fsync: not dirty");
bremfree(bp);
bp->b_flags |= B_BUSY;
splx(s);
(void) bwrite(bp);
goto loop;
}
while (vp->v_numoutput) {
vp->v_flag |= VBWAIT;
(void) tsleep((caddr_t)&vp->v_numoutput, PRIBIO + 1, "msdosfsn", 0);
}
#ifdef DIAGNOSTIC
if (vp->v_dirtyblkhd.lh_first) {
vprint("msdosfs_fsync: dirty", vp);
goto loop;
}
#endif
splx(s);
TIMEVAL_TO_TIMESPEC(&time, &ts);
return deupdat(VTODE(vp), &ts, wait);
}
/*
* Now the whole work of extending a file is done in the write function.
* So nothing to do here.
*/
static int
msdosfs_seek(ap)
struct vop_seek_args /* {
struct vnode *a_vp;
off_t a_oldoff;
off_t a_newoff;
struct ucred *a_cred;
} */ *ap;
{
return 0;
}
static int
msdosfs_remove(ap)
struct vop_remove_args /* {
struct vnode *a_dvp;
struct vnode *a_vp;
struct componentname *a_cnp;
} */ *ap;
{
int error;
struct denode *dep = VTODE(ap->a_vp);
struct denode *ddep = VTODE(ap->a_dvp);
error = removede(ddep,dep);
#ifdef MSDOSFS_DEBUG
printf("msdosfs_remove(), dep %08x, v_usecount %d\n", dep, ap->a_vp->v_usecount);
#endif
if (ddep == dep)
vrele(ap->a_vp);
else
vput(ap->a_vp); /* causes msdosfs_inactive() to be called
* via vrele() */
vput(ap->a_dvp);
return error;
}
/*
* DOS filesystems don't know what links are. But since we already called
* msdosfs_lookup() with create and lockparent, the parent is locked so we
* have to free it before we return the error.
*/
static int
msdosfs_link(ap)
struct vop_link_args /* {
struct vnode *a_tdvp;
struct vnode *a_vp;
struct componentname *a_cnp;
} */ *ap;
{
VOP_ABORTOP(ap->a_tdvp, ap->a_cnp);
vput(ap->a_tdvp);
return EOPNOTSUPP;
}
/*
* Renames on files require moving the denode to a new hash queue since the
* denode's location is used to compute which hash queue to put the file
* in. Unless it is a rename in place. For example "mv a b".
*
* What follows is the basic algorithm:
*
* if (file move) {
* if (dest file exists) {
* remove dest file
* }
* if (dest and src in same directory) {
* rewrite name in existing directory slot
* } else {
* write new entry in dest directory
* update offset and dirclust in denode
* move denode to new hash chain
* clear old directory entry
* }
* } else {
* directory move
* if (dest directory exists) {
* if (dest is not empty) {
* return ENOTEMPTY
* }
* remove dest directory
* }
* if (dest and src in same directory) {
* rewrite name in existing entry
* } else {
* be sure dest is not a child of src directory
* write entry in dest directory
* update "." and ".." in moved directory
* clear old directory entry for moved directory
* }
* }
*
* On entry:
* source's parent directory is unlocked
* source file or directory is unlocked
* destination's parent directory is locked
* destination file or directory is locked if it exists
*
* On exit:
* all denodes should be released
*
* Notes:
* I'm not sure how the memory containing the pathnames pointed at by the
* componentname structures is freed, there may be some memory bleeding
* for each rename done.
*/
static int
msdosfs_rename(ap)
struct vop_rename_args /* {
struct vnode *a_fdvp;
struct vnode *a_fvp;
struct componentname *a_fcnp;
struct vnode *a_tdvp;
struct vnode *a_tvp;
struct componentname *a_tcnp;
} */ *ap;
{
u_char toname[11];
int error;
int newparent = 0;
int sourceisadirectory = 0;
u_long cn;
daddr_t bn;
struct vnode *tvp = ap->a_tvp;
struct denode *fddep; /* from file's parent directory */
struct denode *fdep; /* from file or directory */
struct denode *tddep; /* to file's parent directory */
struct denode *tdep; /* to file or directory */
struct msdosfsmount *pmp;
struct direntry *dotdotp;
struct direntry *ep;
struct buf *bp;
fddep = VTODE(ap->a_fdvp);
fdep = VTODE(ap->a_fvp);
tddep = VTODE(ap->a_tdvp);
tdep = tvp ? VTODE(tvp) : NULL;
pmp = fddep->de_pmp;
/* Check for cross-device rename */
if ((ap->a_fvp->v_mount != ap->a_tdvp->v_mount) ||
(tvp && (ap->a_fvp->v_mount != tvp->v_mount))) {
error = EXDEV;
goto bad;
}
/*
* Convert the filename in tcnp into a dos filename. We copy this
* into the denode and directory entry for the destination
* file/directory.
*/
unix2dosfn((u_char *) ap->a_tcnp->cn_nameptr,
toname, ap->a_tcnp->cn_namelen);
/*
* At this point this is the lock state of the denodes:
* fddep referenced
* fdep referenced
* tddep locked
* tdep locked if it exists
*/
/*
* Be sure we are not renaming ".", "..", or an alias of ".". This
* leads to a crippled directory tree. It's pretty tough to do a
* "ls" or "pwd" with the "." directory entry missing, and "cd .."
* doesn't work if the ".." entry is missing.
*/
if (fdep->de_Attributes & ATTR_DIRECTORY) {
if ((ap->a_fcnp->cn_namelen == 1
&& ap->a_fcnp->cn_nameptr[0] == '.')
|| fddep == fdep
|| (ap->a_fcnp->cn_flags | ap->a_tcnp->cn_flags)
& ISDOTDOT) {
VOP_ABORTOP(ap->a_tdvp, ap->a_tcnp);
vput(ap->a_tdvp);
if (tvp)
vput(tvp);
VOP_ABORTOP(ap->a_fdvp, ap->a_fcnp);
vrele(ap->a_fdvp);
vrele(ap->a_fvp);
return EINVAL;
}
sourceisadirectory = 1;
}
/*
* If we are renaming a directory, and the directory is being moved
* to another directory, then we must be sure the destination
* directory is not in the subtree of the source directory. This
* could orphan everything under the source directory.
* doscheckpath() unlocks the destination's parent directory so we
* must look it up again to relock it.
*/
if (fddep->de_StartCluster != tddep->de_StartCluster)
newparent = 1;
if (sourceisadirectory && newparent) {
if (tdep) {
vput(ap->a_tvp);
tdep = NULL;
}
/* doscheckpath() vput()'s tddep */
error = doscheckpath(fdep, tddep);
tddep = NULL;
if (error)
goto bad;
if ((ap->a_tcnp->cn_flags & SAVESTART) == 0)
panic("msdosfs_rename(): lost to startdir");
error = relookup(ap->a_tdvp, &tvp, ap->a_tcnp);
if (error)
goto bad;
tddep = VTODE(ap->a_tdvp);
tdep = tvp ? VTODE(tvp) : NULL;
}
/*
* If the destination exists, then be sure its type (file or dir)
* matches that of the source. And, if it is a directory make sure
* it is empty. Then delete the destination.
*/
if (tdep) {
if (tdep->de_Attributes & ATTR_DIRECTORY) {
if (!sourceisadirectory) {
error = ENOTDIR;
goto bad;
}
if (!dosdirempty(tdep)) {
error = ENOTEMPTY;
goto bad;
}
cache_purge(DETOV(tddep));
} else { /* destination is file */
if (sourceisadirectory) {
error = EISDIR;
goto bad;
}
}
error = removede(tddep,tdep);
if (error)
goto bad;
vput(ap->a_tvp);
tdep = NULL;
}
/*
* If the source and destination are in the same directory then
* just read in the directory entry, change the name in the
* directory entry and write it back to disk.
*/
if (newparent == 0) {
/* tddep and fddep point to the same denode here */
VOP_LOCK(ap->a_fvp); /* ap->a_fdvp is already locked */
error = readep(fddep->de_pmp, fdep->de_dirclust,
fdep->de_diroffset, &bp, &ep);
if (error) {
VOP_UNLOCK(ap->a_fvp);
goto bad;
}
bcopy(toname, ep->deName, 11);
error = bwrite(bp);
if (error) {
VOP_UNLOCK(ap->a_fvp);
goto bad;
}
bcopy(toname, fdep->de_Name, 11); /* update denode */
/*
* fdep locked fddep and tddep point to the same denode
* which is locked tdep is NULL
*/
} else {
u_long dirsize = 0L;
/*
* If the source and destination are in different
* directories, then mark the entry in the source directory
* as deleted and write a new entry in the destination
* directory. Then move the denode to the correct hash
* chain for its new location in the filesystem. And, if
* we moved a directory, then update its .. entry to point
* to the new parent directory. If we moved a directory
* will also insure that the directory entry on disk has a
* filesize of zero.
*/
VOP_LOCK(ap->a_fvp);
bcopy(toname, fdep->de_Name, 11); /* update denode */
if (fdep->de_Attributes & ATTR_DIRECTORY) {
dirsize = fdep->de_FileSize;
fdep->de_FileSize = 0;
}
error = createde(fdep, tddep, (struct denode **) 0);
if (fdep->de_Attributes & ATTR_DIRECTORY) {
fdep->de_FileSize = dirsize;
}
if (error) {
/* should put back filename */
VOP_UNLOCK(ap->a_fvp);
goto bad;
}
VOP_LOCK(ap->a_fdvp);
error = readep(fddep->de_pmp, fddep->de_fndclust,
fddep->de_fndoffset, &bp, &ep);
if (error) {
VOP_UNLOCK(ap->a_fvp);
VOP_UNLOCK(ap->a_fdvp);
goto bad;
}
ep->deName[0] = SLOT_DELETED;
error = bwrite(bp);
if (error) {
VOP_UNLOCK(ap->a_fvp);
VOP_UNLOCK(ap->a_fdvp);
goto bad;
}
if (!sourceisadirectory) {
fdep->de_dirclust = tddep->de_fndclust;
fdep->de_diroffset = tddep->de_fndoffset;
reinsert(fdep);
}
VOP_UNLOCK(ap->a_fdvp);
}
/* fdep is still locked here */
/*
* If we moved a directory to a new parent directory, then we must
* fixup the ".." entry in the moved directory.
*/
if (sourceisadirectory && newparent) {
cn = fdep->de_StartCluster;
if (cn == MSDOSFSROOT) {
/* this should never happen */
panic("msdosfs_rename(): updating .. in root directory?");
} else {
bn = cntobn(pmp, cn);
}
error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster,
NOCRED, &bp);
if (error) {
/* should really panic here, fs is corrupt */
VOP_UNLOCK(ap->a_fvp);
goto bad;
}
dotdotp = (struct direntry *) bp->b_data + 1;
putushort(dotdotp->deStartCluster, tddep->de_StartCluster);
error = bwrite(bp);
VOP_UNLOCK(ap->a_fvp);
if (error) {
/* should really panic here, fs is corrupt */
goto bad;
}
} else
VOP_UNLOCK(ap->a_fvp);
bad: ;
vrele(DETOV(fdep));
vrele(DETOV(fddep));
if (tdep)
vput(DETOV(tdep));
if (tddep)
vput(DETOV(tddep));
return error;
}
static struct {
struct direntry dot;
struct direntry dotdot;
} dosdirtemplate = {
{
". ", " ", /* the . entry */
ATTR_DIRECTORY, /* file attribute */
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0}, /* resevered */
{210, 4}, {210, 4}, /* time and date */
{0, 0}, /* startcluster */
{0, 0, 0, 0}, /* filesize */
},{
".. ", " ", /* the .. entry */
ATTR_DIRECTORY, /* file attribute */
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0}, /* resevered */
{210, 4}, {210, 4}, /* time and date */
{0, 0}, /* startcluster */
{0, 0, 0, 0}, /* filesize */
}
};
static int
msdosfs_mkdir(ap)
struct vop_mkdir_args /* {
struct vnode *a_dvp;
struvt vnode **a_vpp;
struvt componentname *a_cnp;
struct vattr *a_vap;
} */ *ap;
{
int bn;
int error;
u_long newcluster;
struct denode *pdep;
struct denode *ndep;
struct direntry *denp;
struct denode ndirent;
struct msdosfsmount *pmp;
struct buf *bp;
struct timespec ts;
u_short dDate, dTime;
pdep = VTODE(ap->a_dvp);
/*
* If this is the root directory and there is no space left we
* can't do anything. This is because the root directory can not
* change size.
*/
if (pdep->de_StartCluster == MSDOSFSROOT && pdep->de_fndclust == (u_long)-1) {
free(ap->a_cnp->cn_pnbuf, M_NAMEI);
vput(ap->a_dvp);
return ENOSPC;
}
pmp = pdep->de_pmp;
/*
* Allocate a cluster to hold the about to be created directory.
*/
error = clusteralloc(pmp, 0, 1, CLUST_EOFE, &newcluster, NULL);
if (error) {
free(ap->a_cnp->cn_pnbuf, M_NAMEI);
vput(ap->a_dvp);
return error;
}
/*
* Now fill the cluster with the "." and ".." entries. And write
* the cluster to disk. This way it is there for the parent
* directory to be pointing at if there were a crash.
*/
bn = cntobn(pmp, newcluster);
/* always succeeds */
bp = getblk(pmp->pm_devvp, bn, pmp->pm_bpcluster, 0, 0);
bzero(bp->b_data, pmp->pm_bpcluster);
bcopy(&dosdirtemplate, bp->b_data, sizeof dosdirtemplate);
denp = (struct direntry *) bp->b_data;
putushort(denp->deStartCluster, newcluster);
TIMEVAL_TO_TIMESPEC(&time, &ts);
unix2dostime(&ts, &dDate, &dTime);
putushort(denp->deDate, dDate);
putushort(denp->deTime, dTime);
denp++;
putushort(denp->deStartCluster, pdep->de_StartCluster);
putushort(denp->deDate, dDate);
putushort(denp->deTime, dTime);
error = bwrite(bp);
if (error) {
clusterfree(pmp, newcluster, NULL);
free(ap->a_cnp->cn_pnbuf, M_NAMEI);
vput(ap->a_dvp);
return error;
}
/*
* Now build up a directory entry pointing to the newly allocated
* cluster. This will be written to an empty slot in the parent
* directory.
*/
ndep = &ndirent;
bzero(ndep, sizeof(*ndep));
unix2dosfn((u_char *)ap->a_cnp->cn_nameptr,
ndep->de_Name, ap->a_cnp->cn_namelen);
TIMEVAL_TO_TIMESPEC(&time, &ts);
unix2dostime(&ts, &ndep->de_Date, &ndep->de_Time);
ndep->de_StartCluster = newcluster;
ndep->de_Attributes = ATTR_DIRECTORY;
error = createde(ndep, pdep, &ndep);
if (error) {
clusterfree(pmp, newcluster, NULL);
} else {
*ap->a_vpp = DETOV(ndep);
}
free(ap->a_cnp->cn_pnbuf, M_NAMEI);
#ifdef MSDOSFS_DEBUG
printf("msdosfs_mkdir(): vput(%08x)\n", ap->a_dvp);
#endif
vput(ap->a_dvp);
return error;
}
static int
msdosfs_rmdir(ap)
struct vop_rmdir_args /* {
struct vnode *a_dvp;
struct vnode *a_vp;
struct componentname *a_cnp;
} */ *ap;
{
struct denode *ddep;
struct denode *dep;
int error = 0;
ddep = VTODE(ap->a_dvp); /* parent dir of dir to delete */
dep = VTODE(ap->a_vp);/* directory to delete */
/*
* Don't let "rmdir ." go thru.
*/
if (ddep == dep) {
vrele(ap->a_vp);
vput(ap->a_vp);
return EINVAL;
}
/*
* Be sure the directory being deleted is empty.
*/
if (dosdirempty(dep) == 0) {
error = ENOTEMPTY;
goto out;
}
/*
* Delete the entry from the directory. For dos filesystems this
* gets rid of the directory entry on disk, the in memory copy
* still exists but the de_refcnt is <= 0. This prevents it from
* being found by deget(). When the vput() on dep is done we give
* up access and eventually msdosfs_reclaim() will be called which
* will remove it from the denode cache.
*/
error = removede(ddep,dep);
if (error)
goto out;
/*
* This is where we decrement the link count in the parent
* directory. Since dos filesystems don't do this we just purge
* the name cache and let go of the parent directory denode.
*/
cache_purge(DETOV(ddep));
vput(ap->a_dvp);
ap->a_dvp = NULL;
/*
* Truncate the directory that is being deleted.
*/
error = detrunc(dep, (u_long) 0, IO_SYNC, NOCRED, NULL);
cache_purge(DETOV(dep));
out: ;
if (ap->a_dvp)
vput(ap->a_dvp);
vput(ap->a_vp);
return error;
}
/*
* DOS filesystems don't know what symlinks are.
*/
static int
msdosfs_symlink(ap)
struct vop_symlink_args /* {
struct vnode *a_dvp;
struct vnode **a_vpp;
struct componentname *a_cnp;
struct vattr *a_vap;
char *a_target;
} */ *ap;
{
free(ap->a_cnp->cn_pnbuf, M_NAMEI);
vput(ap->a_dvp);
return EINVAL;
}
/*
* Dummy dirents to simulate the "." and ".." entries of the root directory
* in a dos filesystem. Dos doesn't provide these. Note that each entry
* must be the same size as a dos directory entry (32 bytes).
*/
static struct dos_dirent {
u_long d_fileno;
u_short d_reclen;
u_char d_type;
u_char d_namlen;
u_char d_name[24];
} rootdots[2] = {
{
1, /* d_fileno */
sizeof(struct direntry), /* d_reclen */
DT_DIR, /* d_type */
1, /* d_namlen */
"." /* d_name */
},
{
1, /* d_fileno */
sizeof(struct direntry), /* d_reclen */
DT_DIR, /* d_type */
2, /* d_namlen */
".." /* d_name */
}
};
static int
msdosfs_readdir(ap)
struct vop_readdir_args /* {
struct vnode *a_vp;
struct uio *a_uio;
struct ucred *a_cred;
int *a_eofflag;
u_int *a_cookies;
int a_ncookies;
} */ *ap;
{
int error = 0;
int diff;
char pushout;
long n;
long on;
long lost;
long count;
u_long cn;
u_long fileno;
long bias = 0;
daddr_t bn;
daddr_t lbn;
struct buf *bp;
struct denode *dep = VTODE(ap->a_vp);
struct msdosfsmount *pmp = dep->de_pmp;
struct direntry *dentp;
struct dirent *prev;
struct dirent *crnt;
u_char dirbuf[512]; /* holds converted dos directories */
struct uio *uio = ap->a_uio;
off_t off;
int ncookies = 0;
#ifdef MSDOSFS_DEBUG
printf("msdosfs_readdir(): vp %08x, uio %08x, cred %08x, eofflagp %08x\n",
ap->a_vp, uio, ap->a_cred, ap->a_eofflag);
#endif
/*
* msdosfs_readdir() won't operate properly on regular files since
* it does i/o only with the the filesystem vnode, and hence can
* retrieve the wrong block from the buffer cache for a plain file.
* So, fail attempts to readdir() on a plain file.
*/
if ((dep->de_Attributes & ATTR_DIRECTORY) == 0)
return ENOTDIR;
/*
* If the user buffer is smaller than the size of one dos directory
* entry or the file offset is not a multiple of the size of a
* directory entry, then we fail the read.
*/
count = uio->uio_resid & ~(sizeof(struct direntry) - 1);
lost = uio->uio_resid - count;
if (count < sizeof(struct direntry) ||
(uio->uio_offset & (sizeof(struct direntry) - 1)))
return EINVAL;
uio->uio_resid = count;
uio->uio_iov->iov_len = count;
off = uio->uio_offset;
/*
* If they are reading from the root directory then, we simulate
* the . and .. entries since these don't exist in the root
* directory. We also set the offset bias to make up for having to
* simulate these entries. By this I mean that at file offset 64 we
* read the first entry in the root directory that lives on disk.
*/
if (dep->de_StartCluster == MSDOSFSROOT) {
/*
* printf("msdosfs_readdir(): going after . or .. in root dir, offset %d\n",
* uio->uio_offset);
*/
bias = 2 * sizeof(struct direntry);
if (uio->uio_offset < 2 * sizeof(struct direntry)) {
if (uio->uio_offset
&& uio->uio_offset != sizeof(struct direntry)) {
error = EINVAL;
goto out;
}
n = 1;
if (!uio->uio_offset) {
n = 2;
ncookies++;
}
ncookies++;
error = uiomove((char *) rootdots + uio->uio_offset,
n * sizeof(struct direntry), uio);
}
}
while (!error && uio->uio_resid > 0) {
lbn = (uio->uio_offset - bias) >> pmp->pm_cnshift;
on = (uio->uio_offset - bias) & pmp->pm_crbomask;
n = min((u_long) (pmp->pm_bpcluster - on), uio->uio_resid);
diff = dep->de_FileSize - (uio->uio_offset - bias);
if (diff <= 0)
break;
if (diff < n)
n = diff;
error = pcbmap(dep, lbn, &bn, &cn);
if (error)
break;
error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster, NOCRED, &bp);
n = min(n, pmp->pm_bpcluster - bp->b_resid);
if (error) {
brelse(bp);
return error;
}
/*
* code to convert from dos directory entries to ufs
* directory entries
*/
pushout = 0;
dentp = (struct direntry *)(bp->b_data + on);
prev = 0;
crnt = (struct dirent *) dirbuf;
while ((char *) dentp < bp->b_data + on + n) {
/*
* printf("rd: dentp %08x prev %08x crnt %08x deName %02x attr %02x\n",
* dentp, prev, crnt, dentp->deName[0], dentp->deAttributes);
*/
/*
* If we have an empty entry or a slot from a
* deleted file, or a volume label entry just
* concatenate its space onto the end of the
* previous entry or, manufacture an empty entry if
* there is no previous entry.
*/
if (dentp->deName[0] == SLOT_EMPTY ||
dentp->deName[0] == SLOT_DELETED ||
(dentp->deAttributes & ATTR_VOLUME)) {
if (prev) {
prev->d_reclen += sizeof(struct direntry);
} else {
prev = crnt;
prev->d_fileno = 0;
prev->d_reclen = sizeof(struct direntry);
prev->d_type = DT_UNKNOWN;
prev->d_namlen = 0;
prev->d_name[0] = 0;
ncookies++;
}
} else {
/*
* this computation of d_fileno must match
* the computation of va_fileid in
* msdosfs_getattr
*/
if (dentp->deAttributes & ATTR_DIRECTORY) {
/* if this is the root directory */
fileno = getushort(dentp->deStartCluster);
if (fileno == MSDOSFSROOT)
fileno = 1;
} else {
/*
* if the file's dirent lives in
* root dir
*/
if ((fileno = cn) == MSDOSFSROOT)
fileno = 1;
fileno = (fileno << 16) |
((dentp - (struct direntry *) bp->b_data) & 0xffff);
}
crnt->d_fileno = fileno;
crnt->d_reclen = sizeof(struct direntry);
crnt->d_type = (dentp->deAttributes & ATTR_DIRECTORY)
? DT_DIR : DT_REG;
crnt->d_namlen = dos2unixfn(dentp->deName,
(u_char *)crnt->d_name);
/*
* printf("readdir: file %s, fileno %08x, attr %02x, start %08x\n",
* crnt->d_name, crnt->d_fileno, dentp->deAttributes,
* dentp->deStartCluster);
*/
prev = crnt;
ncookies++;
}
dentp++;
crnt = (struct dirent *) ((char *) crnt + sizeof(struct direntry));
pushout = 1;
/*
* If our intermediate buffer is full then copy its
* contents to user space. I would just use the
* buffer the buf header points to but, I'm afraid
* that when we brelse() it someone else might find
* it in the cache and think its contents are
* valid. Maybe there is a way to invalidate the
* buffer before brelse()'ing it.
*/
if ((u_char *) crnt >= &dirbuf[sizeof dirbuf]) {
pushout = 0;
error = uiomove(dirbuf, sizeof(dirbuf), uio);
if (error)
break;
prev = 0;
crnt = (struct dirent *) dirbuf;
}
}
if (pushout) {
pushout = 0;
error = uiomove(dirbuf, (char *) crnt - (char *) dirbuf,
uio);
}
#if 0
/*
* If we have read everything from this block or have read
* to end of file then we are done with this block. Mark
* it to say the buffer can be reused if need be.
*/
if (n + on == pmp->pm_bpcluster ||
(uio->uio_offset - bias) == dep->de_FileSize)
bp->b_flags |= B_AGE;
#endif /* if 0 */
brelse(bp);
if (n == 0)
break;
}
out: ;
uio->uio_resid += lost;
if (!error && ap->a_ncookies != NULL) {
struct dirent* dpStart;
struct dirent* dpEnd;
struct dirent* dp;
u_int *cookies;
u_int *cookiep;
if (uio->uio_segflg != UIO_SYSSPACE || uio->uio_iovcnt != 1)
panic("msdosfs_readdir: unexpected uio from NFS server");
dpStart = (struct dirent *)
(uio->uio_iov->iov_base - (uio->uio_offset - off));
dpEnd = (struct dirent *) uio->uio_iov->iov_base;
MALLOC(cookies, u_int *, ncookies * sizeof(u_int),
M_TEMP, M_WAITOK);
for (dp = dpStart, cookiep = cookies;
dp < dpEnd;
dp = (struct dirent *)((caddr_t) dp + dp->d_reclen)) {
off += dp->d_reclen;
*cookiep++ = (u_int) off;
}
*ap->a_ncookies = ncookies;
*ap->a_cookies = cookies;
}
/*
* Set the eofflag (NFS uses it)
*/
if (ap->a_eofflag)
if (dep->de_FileSize - (uio->uio_offset - bias) <= 0)
*ap->a_eofflag = 1;
else
*ap->a_eofflag = 0;
return error;
}
/*
* DOS filesystems don't know what symlinks are.
*/
static int
msdosfs_readlink(ap)
struct vop_readlink_args /* {
struct vnode *a_vp;
struct uio *a_uio;
struct ucred *a_cred;
} */ *ap;
{
return EINVAL;
}
static int
msdosfs_abortop(ap)
struct vop_abortop_args /* {
struct vnode *a_dvp;
struct componentname *a_cnp;
} */ *ap;
{
if ((ap->a_cnp->cn_flags & (HASBUF | SAVESTART)) == HASBUF)
FREE(ap->a_cnp->cn_pnbuf, M_NAMEI);
return 0;
}
static int
msdosfs_lock(ap)
struct vop_lock_args /* {
struct vnode *a_vp;
} */ *ap;
{
struct denode *dep = VTODE(ap->a_vp);
while (dep->de_flag & DE_LOCKED) {
dep->de_flag |= DE_WANTED;
if (dep->de_lockholder == curproc->p_pid)
panic("msdosfs_lock: locking against myself");
dep->de_lockwaiter = curproc->p_pid;
(void) tsleep((caddr_t) dep, PINOD, "msdlck", 0);
}
dep->de_lockwaiter = 0;
dep->de_lockholder = curproc->p_pid;
dep->de_flag |= DE_LOCKED;
return 0;
}
static int
msdosfs_unlock(ap)
struct vop_unlock_args /* {
struct vnode *vp;
} */ *ap;
{
struct denode *dep = VTODE(ap->a_vp);
if (!(dep->de_flag & DE_LOCKED))
panic("msdosfs_unlock: denode not locked");
dep->de_lockholder = 0;
dep->de_flag &= ~DE_LOCKED;
if (dep->de_flag & DE_WANTED) {
dep->de_flag &= ~DE_WANTED;
wakeup((caddr_t) dep);
}
return 0;
}
static int
msdosfs_islocked(ap)
struct vop_islocked_args /* {
struct vnode *a_vp;
} */ *ap;
{
return VTODE(ap->a_vp)->de_flag & DE_LOCKED ? 1 : 0;
}
/*
* vp - address of vnode file the file
* bn - which cluster we are interested in mapping to a filesystem block number.
* vpp - returns the vnode for the block special file holding the filesystem
* containing the file of interest
* bnp - address of where to return the filesystem relative block number
*/
static int
msdosfs_bmap(ap)
struct vop_bmap_args /* {
struct vnode *a_vp;
daddr_t a_bn;
struct vnode **a_vpp;
daddr_t *a_bnp;
int *a_runp;
int *a_runb;
} */ *ap;
{
struct denode *dep = VTODE(ap->a_vp);
if (ap->a_vpp != NULL)
*ap->a_vpp = dep->de_devvp;
if (ap->a_bnp == NULL)
return 0;
if (ap->a_runp) {
/*
* Sequential clusters should be counted here.
*/
*ap->a_runp = 0;
}
if (ap->a_runb) {
*ap->a_runb = 0;
}
return pcbmap(dep, ap->a_bn, ap->a_bnp, 0);
}
static int
msdosfs_reallocblks(ap)
struct vop_reallocblks_args /* {
struct vnode *a_vp;
struct cluster_save *a_buflist;
} */ *ap;
{
/* Currently no support for clustering */ /* XXX */
return ENOSPC;
}
static int
msdosfs_strategy(ap)
struct vop_strategy_args /* {
struct buf *a_bp;
} */ *ap;
{
struct buf *bp = ap->a_bp;
struct denode *dep = VTODE(bp->b_vp);
struct vnode *vp;
int error = 0;
if (bp->b_vp->v_type == VBLK || bp->b_vp->v_type == VCHR)
panic("msdosfs_strategy: spec");
/*
* If we don't already know the filesystem relative block number
* then get it using pcbmap(). If pcbmap() returns the block
* number as -1 then we've got a hole in the file. DOS filesystems
* don't allow files with holes, so we shouldn't ever see this.
*/
if (bp->b_blkno == bp->b_lblkno) {
error = pcbmap(dep, bp->b_lblkno, &bp->b_blkno, 0);
if (error)
bp->b_blkno = -1;
if (bp->b_blkno == -1)
clrbuf(bp);
}
if (bp->b_blkno == -1) {
biodone(bp);
return error;
}
#ifdef DIAGNOSTIC
#endif
/*
* Read/write the block from/to the disk that contains the desired
* file block.
*/
vp = dep->de_devvp;
bp->b_dev = vp->v_rdev;
VOCALL(vp->v_op, VOFFSET(vop_strategy), ap);
return 0;
}
static int
msdosfs_print(ap)
struct vop_print_args /* {
struct vnode *vp;
} */ *ap;
{
struct denode *dep = VTODE(ap->a_vp);
printf(
"tag VT_MSDOSFS, startcluster %d, dircluster %ld, diroffset %ld ",
dep->de_StartCluster, dep->de_dirclust, dep->de_diroffset);
printf(" dev %d, %d, %s\n",
major(dep->de_dev), minor(dep->de_dev),
dep->de_flag & DE_LOCKED ? "(LOCKED)" : "");
if (dep->de_lockholder) {
printf(" owner pid %d", (int)dep->de_lockholder);
if (dep->de_lockwaiter)
printf(" waiting pid %d", (int)dep->de_lockwaiter);
printf("\n");
}
return 0;
}
static int
msdosfs_advlock(ap)
struct vop_advlock_args /* {
struct vnode *a_vp;
caddr_t a_id;
int a_op;
struct flock *a_fl;
int a_flags;
} */ *ap;
{
return EINVAL; /* we don't do locking yet */
}
static int
msdosfs_pathconf(ap)
struct vop_pathconf_args /* {
struct vnode *a_vp;
int a_name;
int *a_retval;
} */ *ap;
{
switch (ap->a_name) {
case _PC_LINK_MAX:
*ap->a_retval = 1;
return 0;
case _PC_NAME_MAX:
*ap->a_retval = 12;
return 0;
case _PC_PATH_MAX:
*ap->a_retval = PATH_MAX; /* 255? */
return 0;
case _PC_CHOWN_RESTRICTED:
*ap->a_retval = 1;
return 0;
case _PC_NO_TRUNC:
*ap->a_retval = 0;
return 0;
default:
return EINVAL;
}
}
/* Global vfs data structures for msdosfs */
vop_t **msdosfs_vnodeop_p;
static struct vnodeopv_entry_desc msdosfs_vnodeop_entries[] = {
{ &vop_default_desc, (vop_t *)vn_default_error },
{ &vop_lookup_desc, (vop_t *)msdosfs_lookup }, /* lookup */
{ &vop_create_desc, (vop_t *)msdosfs_create }, /* create */
{ &vop_mknod_desc, (vop_t *)msdosfs_mknod }, /* mknod */
{ &vop_open_desc, (vop_t *)msdosfs_open }, /* open */
{ &vop_close_desc, (vop_t *)msdosfs_close }, /* close */
{ &vop_access_desc, (vop_t *)msdosfs_access }, /* access */
{ &vop_getattr_desc, (vop_t *)msdosfs_getattr }, /* getattr */
{ &vop_setattr_desc, (vop_t *)msdosfs_setattr }, /* setattr */
{ &vop_read_desc, (vop_t *)msdosfs_read }, /* read */
{ &vop_write_desc, (vop_t *)msdosfs_write }, /* write */
{ &vop_ioctl_desc, (vop_t *)msdosfs_ioctl }, /* ioctl */
{ &vop_select_desc, (vop_t *)msdosfs_select }, /* select */
{ &vop_mmap_desc, (vop_t *)msdosfs_mmap }, /* mmap */
{ &vop_fsync_desc, (vop_t *)msdosfs_fsync }, /* fsync */
{ &vop_seek_desc, (vop_t *)msdosfs_seek }, /* seek */
{ &vop_remove_desc, (vop_t *)msdosfs_remove }, /* remove */
{ &vop_link_desc, (vop_t *)msdosfs_link }, /* link */
{ &vop_rename_desc, (vop_t *)msdosfs_rename }, /* rename */
{ &vop_mkdir_desc, (vop_t *)msdosfs_mkdir }, /* mkdir */
{ &vop_rmdir_desc, (vop_t *)msdosfs_rmdir }, /* rmdir */
{ &vop_symlink_desc, (vop_t *)msdosfs_symlink }, /* symlink */
{ &vop_readdir_desc, (vop_t *)msdosfs_readdir }, /* readdir */
{ &vop_readlink_desc, (vop_t *)msdosfs_readlink }, /* readlink */
{ &vop_abortop_desc, (vop_t *)msdosfs_abortop }, /* abortop */
{ &vop_inactive_desc, (vop_t *)msdosfs_inactive }, /* inactive */
{ &vop_reclaim_desc, (vop_t *)msdosfs_reclaim }, /* reclaim */
{ &vop_lock_desc, (vop_t *)msdosfs_lock }, /* lock */
{ &vop_unlock_desc, (vop_t *)msdosfs_unlock }, /* unlock */
{ &vop_bmap_desc, (vop_t *)msdosfs_bmap }, /* bmap */
{ &vop_strategy_desc, (vop_t *)msdosfs_strategy }, /* strategy */
{ &vop_print_desc, (vop_t *)msdosfs_print }, /* print */
{ &vop_islocked_desc, (vop_t *)msdosfs_islocked }, /* islocked */
{ &vop_pathconf_desc, (vop_t *)msdosfs_pathconf }, /* pathconf */
{ &vop_advlock_desc, (vop_t *)msdosfs_advlock }, /* advlock */
{ &vop_reallocblks_desc, (vop_t *)msdosfs_reallocblks }, /* reallocblks */
{ &vop_bwrite_desc, (vop_t *)vn_bwrite }, /* bwrite */
{ NULL, NULL }
};
static struct vnodeopv_desc msdosfs_vnodeop_opv_desc =
{ &msdosfs_vnodeop_p, msdosfs_vnodeop_entries };
VNODEOP_SET(msdosfs_vnodeop_opv_desc);
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