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freebsd/sys/msdosfs/msdosfs_vnops.c
David Greenman efeaf95a41 Untangled the vm.h include file spaghetti.
1995-12-07 12:48:31 +00:00

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/* $Id: msdosfs_vnops.c,v 1.29 1995/12/03 16:42:02 bde 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/file.h> /* define FWRITE ... */
#include <sys/stat.h>
#include <sys/buf.h>
#include <sys/proc.h>
#include <sys/mount.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.ts_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;
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;
/*
* 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;
}
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;
}
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;
vnode_pager_setsize(vp, dep->de_FileSize); /* why? */
}
/*
* 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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