NetBSD/sys/msdosfs/msdosfs_vnops.c

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brought in fixed/renamed/matching MS-DOS FS code, from Jeff Polk <polk@bsdi.com>. His notes are as follows: ------------------------------------------------------------------------------ July 22, 1993 - Changed name of entire package from PCFS to MSDOSFS - Fixed bugs: root directory size in clusters instead of bytes growing directory didn't update in-core size link, symlink, mknod didn't free locked parent (deadlock) lookup returned real error on create and rename instead of EJUSTRETURN rename changed `.' entry in child instead of name entry in parent rename removed `.' entry in child instead of removing entry in parent when moving a directory from one dir to another createde() left new node locked when write of parent failed (deadlock) removede() decremented refcount even on error (rmdir's which failed due to write errors left in-core cache entries inconsistent) changed validation for filesystem to not check for the boot signature since some disks (e.g., mtools) aren't bootable directories are always show current time as modify time (needed for NFS export since DOS never updates dir mod times -- ctime is true create time). - Added support for cookies changes to the readdir() vnode interface (#ifdef __bsdi__) - Punted on the whole problem of inode generation numbers. This means that there's a chance of using a stale file handle to access a new file, but it doesn't appear to be the common case, and I don't see how to generate reasonable generation numbers without changing something on the disk (which is the way the SVR4 filesystem survival kit guys did it). I don't think it would be very safe to change the on-disk format. Jeff Polk (polk@BSDI.COM) ------------------------------------------------------------------------------
1993-08-13 15:35:13 +04:00
/*
* 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
*
* msdosfs_vnops.c,v 1.1 1993/08/13 11:35:40 cgd Exp
brought in fixed/renamed/matching MS-DOS FS code, from Jeff Polk <polk@bsdi.com>. His notes are as follows: ------------------------------------------------------------------------------ July 22, 1993 - Changed name of entire package from PCFS to MSDOSFS - Fixed bugs: root directory size in clusters instead of bytes growing directory didn't update in-core size link, symlink, mknod didn't free locked parent (deadlock) lookup returned real error on create and rename instead of EJUSTRETURN rename changed `.' entry in child instead of name entry in parent rename removed `.' entry in child instead of removing entry in parent when moving a directory from one dir to another createde() left new node locked when write of parent failed (deadlock) removede() decremented refcount even on error (rmdir's which failed due to write errors left in-core cache entries inconsistent) changed validation for filesystem to not check for the boot signature since some disks (e.g., mtools) aren't bootable directories are always show current time as modify time (needed for NFS export since DOS never updates dir mod times -- ctime is true create time). - Added support for cookies changes to the readdir() vnode interface (#ifdef __bsdi__) - Punted on the whole problem of inode generation numbers. This means that there's a chance of using a stale file handle to access a new file, but it doesn't appear to be the common case, and I don't see how to generate reasonable generation numbers without changing something on the disk (which is the way the SVR4 filesystem survival kit guys did it). I don't think it would be very safe to change the on-disk format. Jeff Polk (polk@BSDI.COM) ------------------------------------------------------------------------------
1993-08-13 15:35:13 +04:00
*/
#include "param.h"
#include "systm.h"
#include "namei.h"
#include "resourcevar.h" /* defines plimit structure in proc struct */
#include "kernel.h"
#include "file.h" /* define FWRITE ... */
#include "stat.h"
#include "buf.h"
#include "proc.h"
#include "mount.h"
#include "vnode.h"
#include "specdev.h" /* defines plimit structure in the proc struct */
#include "malloc.h"
#include "dir.h" /* defines dirent structure */
#include "bpb.h"
#include "direntry.h"
#include "denode.h"
#include "msdosfsmount.h"
#include "fat.h"
/*
* 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 ndp->ni_pnbuf, always on error, or
* only if the SAVESTART bit in ni_nameiop is clear on success.
*/
int
msdosfs_create(ndp, vap, p)
struct nameidata *ndp;
struct vattr *vap;
struct proc *p;
{
struct denode ndirent;
struct direntry *ndirp = &ndirent.de_de;
struct denode *dep;
struct denode *pdep = VTODE(ndp->ni_dvp);
int error;
#if defined(MSDOSFSDEBUG)
printf("msdosfs_create(ndp %08x, vap %08x, p %08x\n", ndp, vap, p);
#endif /* defined(MSDOSFSDEBUG) */
/*
* 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.
*/
bzero(&ndirent, sizeof(ndirent));
unix2dostime(&time, (union dosdate *) & ndirp->deDate,
(union dostime *) & ndirp->deTime);
unix2dosfn((u_char *) ndp->ni_ptr, ndirp->deName, ndp->ni_namelen);
ndirp->deAttributes = (vap->va_mode & VWRITE) ? 0 : ATTR_READONLY;
ndirp->deStartCluster = 0;
ndirp->deFileSize = 0;
ndirent.de_pmp = pdep->de_pmp;
ndirent.de_dev = pdep->de_dev;
ndirent.de_devvp = pdep->de_devvp;
if ((error = createde(&ndirent, ndp, &dep)) == 0) {
ndp->ni_vp = DETOV(dep);
if ((ndp->ni_nameiop & SAVESTART) == 0)
free(ndp->ni_pnbuf, M_NAMEI);
}
else {
free(ndp->ni_pnbuf, M_NAMEI);
}
deput(pdep); /* release parent dir */
return error;
}
int
msdosfs_mknod(ndp, vap, cred, p)
struct nameidata *ndp;
struct vattr *vap;
struct ucred *cred;
struct proc *p;
{
int error;
struct denode *pdep = VTODE(ndp->ni_dvp);
switch (vap->va_type) {
case VDIR:
error = msdosfs_mkdir(ndp, vap, p);
break;
/*
* msdosfs_create() sets ndp->ni_vp.
*/
case VREG:
error = msdosfs_create(ndp, vap, p);
break;
default:
error = EINVAL;
free(ndp->ni_pnbuf, M_NAMEI);
deput(pdep);
break;
}
return error;
}
int
msdosfs_open(vp, mode, cred, p)
struct vnode *vp;
int mode;
struct ucred *cred;
struct proc *p;
{
return 0;
}
int
msdosfs_close(vp, fflag, cred, p)
struct vnode *vp;
int fflag;
struct ucred *cred;
struct proc *p;
{
struct denode *dep = VTODE(vp);
if (vp->v_usecount > 1 && !(dep->de_flag & DELOCKED))
DETIMES(dep, &time);
return 0;
}
int
msdosfs_access(vp, mode, cred, p)
struct vnode *vp;
int mode;
struct ucred *cred;
struct proc *p;
{
int dosmode;
struct denode *dep = VTODE(vp);
/*
* Root gets to do anything. Even execute a file without the x-bit
* on? But, for dos filesystems every file is executable. I may
* regret this.
*/
if (cred->cr_uid == 0)
return 0;
/*
* mode is filled with a combination of VREAD, VWRITE, and/or VEXEC
* bits turned on. In an octal number these are the Y in 0Y00.
*
* Since the dos filesystem doesn't have the concept of file ownership
* we just give everybody read and execute access and write access
* if the readonly bit is off.
*/
dosmode = VEXEC | VREAD |
((dep->de_Attributes & ATTR_READONLY) ? 0 : VWRITE);
return ((dosmode & mode) != 0) ? 0 : EACCES;
}
int
msdosfs_getattr(vp, vap, cred, p)
struct vnode *vp;
struct vattr *vap;
struct ucred *cred;
struct proc *p;
{
u_int cn;
struct denode *dep = VTODE(vp);
DETIMES(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 = (dep->de_Attributes & ATTR_READONLY) ? 0555 : 0777;
if (dep->de_Attributes & ATTR_DIRECTORY)
vap->va_mode |= S_IFDIR;
vap->va_nlink = 1;
vap->va_gid = 0;
vap->va_uid = 0;
vap->va_rdev = 0;
vap->va_size = dep->de_FileSize;
vap->va_size_rsv = 0;
dos2unixtime((union dosdate *) & dep->de_Date,
(union dostime *) & dep->de_Time, &vap->va_atime);
vap->va_atime.tv_usec = 0;
vap->va_mtime.tv_sec = vap->va_atime.tv_sec;
vap->va_mtime.tv_usec = 0;
#ifndef MSDOSFS_NODIRMOD
if (vap->va_mode & S_IFDIR) {
vap->va_mtime.tv_sec = time.tv_sec;
vap->va_mtime.tv_usec = time.tv_usec;
}
#endif
vap->va_ctime.tv_sec = vap->va_atime.tv_sec;
vap->va_ctime.tv_usec = 0;
vap->va_flags = dep->de_flag;
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_bytes_rsv = 0;
vap->va_type = vp->v_type;
return 0;
}
int
msdosfs_setattr(vp, vap, cred, p)
struct vnode *vp;
struct vattr *vap;
struct ucred *cred;
struct proc *p;
{
int error = 0;
struct denode *dep = VTODE(vp);
#if defined(MSDOSFSDEBUG)
printf("msdosfs_setattr(): vp %08x, vap %08x, cred %08x, p %08x\n",
vp, vap, cred, p);
#endif /* defined(MSDOSFSDEBUG) */
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) ||
(vap->va_uid != (u_short) VNOVAL) ||
(vap->va_gid != (u_short) VNOVAL) ||
(vap->va_atime.tv_sec != VNOVAL)) {
#if defined(MSDOSFSDEBUG)
printf("msdosfs_setattr(): returning EINVAL\n");
printf(" va_type %d, va_nlink %x, va_fsid %x, va_fileid %x\n",
vap->va_type, vap->va_nlink, vap->va_fsid, vap->va_fileid);
printf(" va_blocksize %x, va_rdev %x, va_bytes %x, va_gen %x\n",
vap->va_blocksize, vap->va_rdev, vap->va_bytes, vap->va_gen);
printf(" va_uid %x, va_gid %x, va_atime.tv_sec %x\n",
vap->va_uid, vap->va_gid, vap->va_atime.tv_sec);
#endif /* defined(MSDOSFSDEBUG) */
return EINVAL;
}
if (vap->va_size != VNOVAL) {
if (vp->v_type == VDIR)
return EISDIR;
if (error = detrunc(dep, vap->va_size, 0))
return error;
}
if (vap->va_mtime.tv_sec != VNOVAL) {
dep->de_flag |= DEUPD;
if (error = deupdat(dep, &vap->va_mtime, 1))
return error;
}
/*
* DOS files only have the ability to have thier writability
* attribute set, so we use the owner write bit to set the readonly
* attribute.
*/
if (vap->va_mode != (u_short) VNOVAL) {
/* 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 |= DEUPD;
}
if (vap->va_flags != VNOVAL) {
if (error = suser(cred, &p->p_acflag))
return error;
if (cred->cr_uid == 0)
dep->de_flag = vap->va_flags;
else {
dep->de_flag &= 0xffff0000;
dep->de_flag |= (vap->va_flags & 0xffff);
}
dep->de_flag |= DEUPD;
}
return error;
}
int
msdosfs_read(vp, uio, ioflag, cred)
struct vnode *vp;
struct uio *uio;
int ioflag;
struct ucred *cred;
{
int error = 0;
int diff;
int isadir;
long n;
long on;
daddr_t bn;
daddr_t lbn;
daddr_t rablock;
struct buf *bp;
struct denode *dep = VTODE(vp);
struct msdosfsmount *pmp = dep->de_pmp;
/*
* 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) {
error = breada(vp, lbn, pmp->pm_bpcluster,
rablock, pmp->pm_bpcluster, 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_un.b_addr + 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.
*/
int
msdosfs_write(vp, uio, ioflag, cred)
struct vnode *vp;
struct uio *uio;
int ioflag;
struct ucred *cred;
{
int n;
int isadir;
int croffset;
int resid;
int osize;
int error;
u_long cluster;
u_long nextcluster;
u_long lastcluster;
daddr_t bn;
struct buf *bp;
struct proc *p = uio->uio_procp;
struct vnode *thisvp;
struct denode *dep = VTODE(vp);
struct msdosfsmount *pmp = dep->de_pmp;
#if defined(MSDOSFSDEBUG)
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 /* defined(MSDOSFSDEBUG) */
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. We do this by calling our seek function.
* This could probably be cleaned up someday.
*/
if (uio->uio_offset > dep->de_FileSize) {
error = msdosfs_seek(vp, (off_t) 0, uio->uio_offset, cred);
if (error)
return error;
}
/*
* Remember some values in case the write fails.
*/
resid = uio->uio_resid;
osize = dep->de_FileSize;
do {
bn = uio->uio_offset >> pmp->pm_cnshift;
/*
* If we are appending to the file and we are on a cluster
* boundary, then allocate a new cluster and chain it onto
* the file.
*/
if (uio->uio_offset == dep->de_FileSize &&
(uio->uio_offset & pmp->pm_crbomask) == 0) {
if (error = extendfile(dep, &bp, 0))
break;
}
else {
/*
* The block we need to write into exists, so just
* read it in.
*/
if (isadir) {
error = pcbmap(dep, bn, &bn, 0);
if (error)
return error;
}
error = bread(thisvp, bn, pmp->pm_bpcluster, cred, &bp);
if (error)
return error;
}
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? */
}
(void) vnode_pager_uncache(vp); /* why not? */
/*
* Should these vnode_pager_* functions be done on dir
* files?
*/
/*
* Copy the data from user space into the buf header.
*/
error = uiomove(bp->b_un.b_addr + 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) {
bp->b_flags |= B_AGE;
bawrite(bp);
}
else
bdwrite(bp);
dep->de_flag |= DEUPD;
} 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.
*/
if (error && (ioflag & IO_UNIT)) {
detrunc(dep, osize, ioflag & IO_SYNC);
uio->uio_offset -= resid - uio->uio_resid;
uio->uio_resid = resid;
}
if (!error && (ioflag & IO_UNIT))
error = deupdat(dep, &time, 1);
return error;
}
int
msdosfs_ioctl(vp, com, data, fflag, cred, p)
struct vnode *vp;
int com;
caddr_t data;
struct ucred *cred;
struct proc *p;
{
return ENOTTY;
}
int
msdosfs_select(vp, which, fflags, cred, p)
struct vnode *vp;
int which;
int fflags;
struct ucred *cred;
struct proc *p;
{
return 1; /* DOS filesystems never block? */
}
int
msdosfs_mmap(vp, fflags, cred, p)
struct vnode *vp;
int fflags;
struct ucred *cred;
struct proc *p;
{
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.
*/
int
msdosfs_fsync(vp, fflags, cred, waitfor, p)
struct vnode *vp;
int fflags;
struct ucred *cred;
int waitfor;
struct proc *p;
{
struct denode *dep = VTODE(vp);
if (fflags & FWRITE)
dep->de_flag |= DEUPD;
/*
* Does this call to vflushbuf() do anything? I can find no code
* anywhere that sets v_dirtyblkhd in the vnode, which vflushbuf()
* seems to depend upon.
*/
vflushbuf(vp, waitfor == MNT_WAIT ? B_SYNC : 0);
return deupdat(dep, &time, waitfor == MNT_WAIT);
}
/*
* Since the dos filesystem does not allow files with holes in them we must
* fill the file with zeroed blocks when a seek past the end of file
* happens.
*
* It seems that nothing in the kernel calls the filesystem specific file seek
* functions. And, someone on the net told me that NFS never sends
* announcements of seeks to the server. So, if msdosfs ever becomes NFS
* mountable it will have to use other means to fill in holes in what would
* be a sparse file. (This appears fixed since msdosfs_write() calls seek
* before writing if the offset is past EOF)
*/
int
msdosfs_seek(vp, oldoff, newoff, cred)
struct vnode *vp;
off_t oldoff;
off_t newoff;
struct ucred *cred;
{
int error = 0;
off_t foff;
daddr_t bn;
u_long cluster;
u_long lastcluster;
struct buf *bp;
struct denode *dep = VTODE(vp);
struct msdosfsmount *pmp = dep->de_pmp;
#if defined(MSDOSFSDEBUG)
printf("msdosfs_seek(vp %08x, oldoff %d, newoff %d, cred %08x)\n",
vp, oldoff, newoff, cred);
#endif /* defined(MSDOSFSDEBUG) */
/*
* Compute the offset of the first byte after the last block in the
* file. If seeking beyond the end of file then fill the file with
* zeroed blocks up to the seek address.
*/
foff = (dep->de_FileSize + (pmp->pm_bpcluster - 1)) & ~pmp->pm_crbomask;
#if defined(MSDOSFSDEBUG)
printf("seek: newoff %d > foff %d\n", newoff, foff);
#endif /* defined(MSDOSFSDEBUG) */
if (newoff > foff) {
/*
* If this is the root directory and we are attempting to
* seek beyond the end disallow it. DOS filesystem root
* directories can not grow.
*/
if (vp->v_flag & VROOT)
return EINVAL;
/*
* If this is a directory and the caller is not root, then
* do not let them seek beyond the end of file. If we
* allowed this then users could cause directories to grow.
* Is this really that important?
*/
if (dep->de_Attributes & ATTR_DIRECTORY) {
if (error = suser(cred, NULL)) {
return error;
}
}
/*
* Allocate and chain together as many clusters as are
* needed to get to newoff.
*/
while (foff < newoff) {
if (error = extendfile(dep, &bp, 0))
return error;
dep->de_flag |= DEUPD;
bdwrite(bp);
foff += pmp->pm_bpcluster;
dep->de_FileSize += pmp->pm_bpcluster;
} /* end while() */
dep->de_FileSize = newoff;
return deupdat(dep, &time);
}
return 0;
}
int
msdosfs_remove(ndp, p)
struct nameidata *ndp;
struct proc *p;
{
int error;
struct denode *dep = VTODE(ndp->ni_vp);
struct denode *ddep = VTODE(ndp->ni_dvp);
error = removede(ndp);
#if defined(MSDOSFSDEBUG)
printf("msdosfs_remove(), dep %08x, v_usecount %d\n", dep, ndp->ni_vp->v_usecount);
#endif /* defined(MSDOSFSDEBUG) */
if (ddep == dep)
vrele(DETOV(dep));
else
deput(dep); /* causes msdosfs_inactive() to be called
* via vrele() */
deput(ddep);
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.
*/
int
msdosfs_link(vp, ndp, p)
struct vnode *vp;
struct nameidata *ndp;
struct proc *p;
{
struct denode *pdep = VTODE(ndp->ni_dvp);
free(ndp->ni_pnbuf, M_NAMEI);
deput(pdep);
return EINVAL;
}
/*
* 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 update offset and dirclust in denode move denode
* to new hash chain 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 nameidata structures is
* freed, there may be some memory bleeding for each rename done.
*/
int
msdosfs_rename(fndp, tndp, p)
struct nameidata *fndp;
struct nameidata *tndp;
struct proc *p;
{
u_char toname[11];
int error;
int newparent = 0;
int sourceisadirectory = 0;
u_long to_dirclust;
u_long to_diroffset;
u_long cn;
daddr_t bn;
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;
#if defined(MSDOSFSDEBUG)
printf("msdosfs_rename(fndp %08x, tndp %08x, p %08x\n", fndp, tndp, p);
#endif /* defined(MSDOSFSDEBUG) */
fddep = VTODE(fndp->ni_dvp);
fdep = VTODE(fndp->ni_vp);
tddep = VTODE(tndp->ni_dvp);
tdep = tndp->ni_vp ? VTODE(tndp->ni_vp) : NULL;
pmp = fddep->de_pmp;
/*
* Convert the filename in tdnp into a dos filename. We copy this
* into the denode and directory entry for the destination
* file/directory.
*/
unix2dosfn((u_char *) tndp->ni_ptr, toname, tndp->ni_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 ((fndp->ni_namelen == 1 && fndp->ni_ptr[0] == '.') ||
fddep == fdep || /* won't happen ? */
fndp->ni_isdotdot) {
VOP_ABORTOP(tndp);
vput(tndp->ni_dvp);
if (tndp->ni_vp)
vput(tndp->ni_vp);
VOP_ABORTOP(fndp);
vrele(fndp->ni_dvp);
vrele(fndp->ni_vp);
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) {
deput(tdep);
tdep = NULL;
}
/* doscheckpath() deput()'s tddep */
error = doscheckpath(fdep, tddep, tndp->ni_cred);
tddep = NULL;
if (error) {
goto bad;
}
if ((tndp->ni_nameiop & SAVESTART) == 0)
panic("msdosfs_rename(): lost to startdir");
if (error = lookup(tndp, p)) {
goto bad;
}
tddep = VTODE(tndp->ni_dvp);
tdep = tndp->ni_vp ? VTODE(tndp->ni_vp) : 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;
}
}
else { /* destination is file */
if (sourceisadirectory) {
error = EISDIR;
goto bad;
}
}
to_dirclust = tdep->de_dirclust;
to_diroffset = tdep->de_diroffset;
if (error = removede(tndp)) {
goto bad;
}
deput(tdep);
tdep = NULL;
/*
* Remember where the slot was for createde().
*/
tndp->ni_msdosfs.msdosfs_count = 1;
tndp->ni_msdosfs.msdosfs_cluster = to_dirclust;
tndp->ni_msdosfs.msdosfs_offset = to_diroffset;
}
/*
* 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 */
DELOCK(fdep); /* tddep is already locked */
if (error = readep(fdep->de_pmp,
fndp->ni_msdosfs.msdosfs_cluster,
fndp->ni_msdosfs.msdosfs_offset,
&bp, &ep)) {
DEUNLOCK(fdep);
goto bad;
}
bcopy(toname, ep->deName, 11);
if (error = bwrite(bp)) {
DEUNLOCK(fdep);
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 unlocked and unreferenced
*/
}
else {
u_long dirsize;
/*
* 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.
*/
DELOCK(fdep);
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, tndp, (struct denode **) 0);
if (fdep->de_Attributes & ATTR_DIRECTORY) {
fdep->de_FileSize = dirsize;
}
if (error) {
/* should put back filename */
DEUNLOCK(fdep);
goto bad;
}
DELOCK(fddep);
if (error = readep(fdep->de_pmp,
fndp->ni_msdosfs.msdosfs_cluster,
fndp->ni_msdosfs.msdosfs_offset,
&bp, &ep)) {
DEUNLOCK(fdep);
DEUNLOCK(fddep);
goto bad;
}
ep->deName[0] = SLOT_DELETED;
if (error = bwrite(bp)) {
DEUNLOCK(fdep);
DEUNLOCK(fddep);
goto bad;
}
fdep->de_dirclust = tndp->ni_msdosfs.msdosfs_cluster;
fdep->de_diroffset = tndp->ni_msdosfs.msdosfs_offset;
reinsert(fdep);
DEUNLOCK(fddep);
}
/* 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?\n");
}
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 */
DEUNLOCK(fdep);
goto bad;
}
dotdotp = (struct direntry *) bp->b_un.b_addr + 1;
dotdotp->deStartCluster = tddep->de_StartCluster;
error = bwrite(bp);
DEUNLOCK(fdep);
if (error) {
/* should really panic here, fs is corrupt */
goto bad;
}
}
else {
DEUNLOCK(fdep);
}
bad: ;
vrele(DETOV(fdep));
vrele(DETOV(fddep));
if (tdep)
vput(DETOV(tdep));
if (tddep)
vput(DETOV(tddep));
return error;
}
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 */
1234, 1234, /* time and date */
0, /* startcluster */
0, /* filesize */
".. ", " ", /* the .. entry */
ATTR_DIRECTORY, /* file attribute */
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* resevered */
1234, 1234, /* time and date */
0, /* startcluster */
0, /* filesize */
};
int
msdosfs_mkdir(ndp, vap, p)
struct nameidata *ndp;
struct vattr *vap;
struct proc *p;
{
int bn;
int error;
u_long newcluster;
struct denode *pdep;
struct denode *ndep;
struct vnode *pvp;
struct direntry *denp;
struct denode ndirent;
struct msdosfsmount *pmp;
struct buf *bp;
pvp = ndp->ni_dvp;
pdep = VTODE(pvp);
/*
* 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 && ndp->ni_msdosfs.msdosfs_count == 0) {
free(ndp->ni_pnbuf, M_NAMEI);
deput(pdep);
return ENOSPC;
}
pmp = pdep->de_pmp;
/*
* Allocate a cluster to hold the about to be created directory.
*/
if (error = clusteralloc(pmp, &newcluster, CLUST_EOFE)) {
free(ndp->ni_pnbuf, M_NAMEI);
deput(pdep);
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);
bp = getblk(pmp->pm_devvp, bn, pmp->pm_bpcluster); /* always succeeds */
bzero(bp->b_un.b_addr, pmp->pm_bpcluster);
bcopy(&dosdirtemplate, bp->b_un.b_addr, sizeof dosdirtemplate);
denp = (struct direntry *) bp->b_un.b_addr;
denp->deStartCluster = newcluster;
unix2dostime(&time, (union dosdate *) & denp->deDate,
(union dostime *) & denp->deTime);
denp++;
denp->deStartCluster = pdep->de_StartCluster;
unix2dostime(&time, (union dosdate *) & denp->deDate,
(union dostime *) & denp->deTime);
if (error = bwrite(bp)) {
clusterfree(pmp, newcluster, NULL);
free(ndp->ni_pnbuf, M_NAMEI);
deput(pdep);
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 *) ndp->ni_ptr, ndep->de_Name, ndp->ni_namelen);
unix2dostime(&time, (union dosdate *) & ndep->de_Date,
(union dostime *) & ndep->de_Time);
ndep->de_StartCluster = newcluster;
ndep->de_Attributes = ATTR_DIRECTORY;
ndep->de_pmp = pmp; /* createde() needs this */
error = createde(ndep, ndp, &ndep);
if (error) {
clusterfree(pmp, newcluster, NULL);
}
else {
ndp->ni_vp = DETOV(ndep);
}
free(ndp->ni_pnbuf, M_NAMEI);
#if defined(MSDOSFSDEBUG)
printf("msdosfs_mkdir(): deput(%08x), vnode %08x\n", pdep, DETOV(pdep));
#endif /* defined(MSDOSFSDEBUG) */
deput(pdep);
return error;
}
int
msdosfs_rmdir(ndp, p)
struct nameidata *ndp;
struct proc *p;
{
struct denode *ddep;
struct denode *dep;
int error = 0;
ddep = VTODE(ndp->ni_dvp); /* parent dir of dir to delete */
dep = VTODE(ndp->ni_vp);/* directory to delete */
/*
* Don't let "rmdir ." go thru.
*/
if (ddep == dep) {
vrele(DETOV(dep));
deput(dep);
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 deput() on dep is done we give
* up access and eventually msdosfs_reclaim() will be called which
* will remove it from the denode cache.
*/
if (error = removede(ndp))
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));
deput(ddep);
ndp->ni_dvp = NULL; /* getting rid of parent dir pointer? */
/*
* Truncate the directory that is being deleted.
*/
error = detrunc(dep, (u_long) 0, IO_SYNC);
cache_purge(DETOV(dep));
out: ;
if (ndp->ni_dvp)
deput(ddep);
deput(dep);
return error;
}
/*
* DOS filesystems don't know what symlinks are.
*/
int
msdosfs_symlink(ndp, vap, target, p)
struct nameidata *ndp;
struct vattr *vap;
char *target;
struct proc *p;
{
struct denode *pdep = VTODE(ndp->ni_dvp);
free(ndp->ni_pnbuf, M_NAMEI);
deput(pdep);
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).
*/
struct dos_dirent {
u_long d_fileno;
u_short d_reclen;
u_short d_namlen;
u_char d_name[24];
} rootdots[2] = {
{
1, /* d_fileno */
sizeof(struct direntry), /* d_reclen */
1, /* d_namlen */
"." /* d_name */
},
{
1, /* d_fileno */
sizeof(struct direntry), /* d_reclen */
2, /* d_namlen */
".." /* d_name */
}
};
int
msdosfs_readdir(vp, uio, cred, eofflagp, cookies, ncookies)
struct vnode *vp;
struct uio *uio;
struct ucred *cred;
int *eofflagp;
u_int *cookies;
int ncookies;
{
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(vp);
struct msdosfsmount *pmp = dep->de_pmp;
struct direntry *dentp;
struct dirent *prev;
struct dirent *crnt;
u_char dirbuf[512]; /* holds converted dos directories */
int i = 0;
#if defined(MSDOSFSDEBUG)
printf("msdosfs_readdir(): vp %08x, uio %08x, cred %08x, eofflagp %08x\n",
vp, uio, cred, eofflagp);
#endif /* defined(MSDOSFSDEBUG) */
if (!cookies)
ncookies = 1;
brought in fixed/renamed/matching MS-DOS FS code, from Jeff Polk <polk@bsdi.com>. His notes are as follows: ------------------------------------------------------------------------------ July 22, 1993 - Changed name of entire package from PCFS to MSDOSFS - Fixed bugs: root directory size in clusters instead of bytes growing directory didn't update in-core size link, symlink, mknod didn't free locked parent (deadlock) lookup returned real error on create and rename instead of EJUSTRETURN rename changed `.' entry in child instead of name entry in parent rename removed `.' entry in child instead of removing entry in parent when moving a directory from one dir to another createde() left new node locked when write of parent failed (deadlock) removede() decremented refcount even on error (rmdir's which failed due to write errors left in-core cache entries inconsistent) changed validation for filesystem to not check for the boot signature since some disks (e.g., mtools) aren't bootable directories are always show current time as modify time (needed for NFS export since DOS never updates dir mod times -- ctime is true create time). - Added support for cookies changes to the readdir() vnode interface (#ifdef __bsdi__) - Punted on the whole problem of inode generation numbers. This means that there's a chance of using a stale file handle to access a new file, but it doesn't appear to be the common case, and I don't see how to generate reasonable generation numbers without changing something on the disk (which is the way the SVR4 filesystem survival kit guys did it). I don't think it would be very safe to change the on-disk format. Jeff Polk (polk@BSDI.COM) ------------------------------------------------------------------------------
1993-08-13 15:35:13 +04:00
/*
* 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;
/*
* 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;
brought in fixed/renamed/matching MS-DOS FS code, from Jeff Polk <polk@bsdi.com>. His notes are as follows: ------------------------------------------------------------------------------ July 22, 1993 - Changed name of entire package from PCFS to MSDOSFS - Fixed bugs: root directory size in clusters instead of bytes growing directory didn't update in-core size link, symlink, mknod didn't free locked parent (deadlock) lookup returned real error on create and rename instead of EJUSTRETURN rename changed `.' entry in child instead of name entry in parent rename removed `.' entry in child instead of removing entry in parent when moving a directory from one dir to another createde() left new node locked when write of parent failed (deadlock) removede() decremented refcount even on error (rmdir's which failed due to write errors left in-core cache entries inconsistent) changed validation for filesystem to not check for the boot signature since some disks (e.g., mtools) aren't bootable directories are always show current time as modify time (needed for NFS export since DOS never updates dir mod times -- ctime is true create time). - Added support for cookies changes to the readdir() vnode interface (#ifdef __bsdi__) - Punted on the whole problem of inode generation numbers. This means that there's a chance of using a stale file handle to access a new file, but it doesn't appear to be the common case, and I don't see how to generate reasonable generation numbers without changing something on the disk (which is the way the SVR4 filesystem survival kit guys did it). I don't think it would be very safe to change the on-disk format. Jeff Polk (polk@BSDI.COM) ------------------------------------------------------------------------------
1993-08-13 15:35:13 +04:00
goto out;
}
n = 1;
if (!uio->uio_offset) {
n = 2;
if (cookies) {
*cookies++ = sizeof(struct direntry);
ncookies--;
}
}
if (cookies) {
if (ncookies-- <= 0)
n--;
else
*cookies++ = 2 * sizeof(struct direntry);
}
error = uiomove((char *) rootdots + uio->uio_offset,
n * sizeof(struct direntry), uio);
brought in fixed/renamed/matching MS-DOS FS code, from Jeff Polk <polk@bsdi.com>. His notes are as follows: ------------------------------------------------------------------------------ July 22, 1993 - Changed name of entire package from PCFS to MSDOSFS - Fixed bugs: root directory size in clusters instead of bytes growing directory didn't update in-core size link, symlink, mknod didn't free locked parent (deadlock) lookup returned real error on create and rename instead of EJUSTRETURN rename changed `.' entry in child instead of name entry in parent rename removed `.' entry in child instead of removing entry in parent when moving a directory from one dir to another createde() left new node locked when write of parent failed (deadlock) removede() decremented refcount even on error (rmdir's which failed due to write errors left in-core cache entries inconsistent) changed validation for filesystem to not check for the boot signature since some disks (e.g., mtools) aren't bootable directories are always show current time as modify time (needed for NFS export since DOS never updates dir mod times -- ctime is true create time). - Added support for cookies changes to the readdir() vnode interface (#ifdef __bsdi__) - Punted on the whole problem of inode generation numbers. This means that there's a chance of using a stale file handle to access a new file, but it doesn't appear to be the common case, and I don't see how to generate reasonable generation numbers without changing something on the disk (which is the way the SVR4 filesystem survival kit guys did it). I don't think it would be very safe to change the on-disk format. Jeff Polk (polk@BSDI.COM) ------------------------------------------------------------------------------
1993-08-13 15:35:13 +04:00
}
}
while (!error && uio->uio_resid > 0 && ncookies > 0) {
brought in fixed/renamed/matching MS-DOS FS code, from Jeff Polk <polk@bsdi.com>. His notes are as follows: ------------------------------------------------------------------------------ July 22, 1993 - Changed name of entire package from PCFS to MSDOSFS - Fixed bugs: root directory size in clusters instead of bytes growing directory didn't update in-core size link, symlink, mknod didn't free locked parent (deadlock) lookup returned real error on create and rename instead of EJUSTRETURN rename changed `.' entry in child instead of name entry in parent rename removed `.' entry in child instead of removing entry in parent when moving a directory from one dir to another createde() left new node locked when write of parent failed (deadlock) removede() decremented refcount even on error (rmdir's which failed due to write errors left in-core cache entries inconsistent) changed validation for filesystem to not check for the boot signature since some disks (e.g., mtools) aren't bootable directories are always show current time as modify time (needed for NFS export since DOS never updates dir mod times -- ctime is true create time). - Added support for cookies changes to the readdir() vnode interface (#ifdef __bsdi__) - Punted on the whole problem of inode generation numbers. This means that there's a chance of using a stale file handle to access a new file, but it doesn't appear to be the common case, and I don't see how to generate reasonable generation numbers without changing something on the disk (which is the way the SVR4 filesystem survival kit guys did it). I don't think it would be very safe to change the on-disk format. Jeff Polk (polk@BSDI.COM) ------------------------------------------------------------------------------
1993-08-13 15:35:13 +04:00
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)
return 0;
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_un.b_addr + on);
prev = 0;
crnt = (struct dirent *) dirbuf;
while ((char *) dentp < bp->b_un.b_addr + 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);
if (cookies) {
ncookies++;
cookies--;
}
brought in fixed/renamed/matching MS-DOS FS code, from Jeff Polk <polk@bsdi.com>. His notes are as follows: ------------------------------------------------------------------------------ July 22, 1993 - Changed name of entire package from PCFS to MSDOSFS - Fixed bugs: root directory size in clusters instead of bytes growing directory didn't update in-core size link, symlink, mknod didn't free locked parent (deadlock) lookup returned real error on create and rename instead of EJUSTRETURN rename changed `.' entry in child instead of name entry in parent rename removed `.' entry in child instead of removing entry in parent when moving a directory from one dir to another createde() left new node locked when write of parent failed (deadlock) removede() decremented refcount even on error (rmdir's which failed due to write errors left in-core cache entries inconsistent) changed validation for filesystem to not check for the boot signature since some disks (e.g., mtools) aren't bootable directories are always show current time as modify time (needed for NFS export since DOS never updates dir mod times -- ctime is true create time). - Added support for cookies changes to the readdir() vnode interface (#ifdef __bsdi__) - Punted on the whole problem of inode generation numbers. This means that there's a chance of using a stale file handle to access a new file, but it doesn't appear to be the common case, and I don't see how to generate reasonable generation numbers without changing something on the disk (which is the way the SVR4 filesystem survival kit guys did it). I don't think it would be very safe to change the on-disk format. Jeff Polk (polk@BSDI.COM) ------------------------------------------------------------------------------
1993-08-13 15:35:13 +04:00
}
else {
prev = crnt;
prev->d_fileno = 0;
prev->d_reclen = sizeof(struct direntry);
prev->d_namlen = 0;
prev->d_name[0] = 0;
}
}
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 */
if ((fileno = dentp->deStartCluster) == 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_un.b_addr) & 0xffff);
}
crnt->d_fileno = fileno;
crnt->d_reclen = sizeof(struct direntry);
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;
}
dentp++;
if (cookies) {
*cookies++ = (u_int)((char *)dentp - bp->b_un.b_addr - on)
+ uio->uio_offset;
ncookies--;
}
brought in fixed/renamed/matching MS-DOS FS code, from Jeff Polk <polk@bsdi.com>. His notes are as follows: ------------------------------------------------------------------------------ July 22, 1993 - Changed name of entire package from PCFS to MSDOSFS - Fixed bugs: root directory size in clusters instead of bytes growing directory didn't update in-core size link, symlink, mknod didn't free locked parent (deadlock) lookup returned real error on create and rename instead of EJUSTRETURN rename changed `.' entry in child instead of name entry in parent rename removed `.' entry in child instead of removing entry in parent when moving a directory from one dir to another createde() left new node locked when write of parent failed (deadlock) removede() decremented refcount even on error (rmdir's which failed due to write errors left in-core cache entries inconsistent) changed validation for filesystem to not check for the boot signature since some disks (e.g., mtools) aren't bootable directories are always show current time as modify time (needed for NFS export since DOS never updates dir mod times -- ctime is true create time). - Added support for cookies changes to the readdir() vnode interface (#ifdef __bsdi__) - Punted on the whole problem of inode generation numbers. This means that there's a chance of using a stale file handle to access a new file, but it doesn't appear to be the common case, and I don't see how to generate reasonable generation numbers without changing something on the disk (which is the way the SVR4 filesystem survival kit guys did it). I don't think it would be very safe to change the on-disk format. Jeff Polk (polk@BSDI.COM) ------------------------------------------------------------------------------
1993-08-13 15:35:13 +04:00
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 (ncookies <= 0)
brought in fixed/renamed/matching MS-DOS FS code, from Jeff Polk <polk@bsdi.com>. His notes are as follows: ------------------------------------------------------------------------------ July 22, 1993 - Changed name of entire package from PCFS to MSDOSFS - Fixed bugs: root directory size in clusters instead of bytes growing directory didn't update in-core size link, symlink, mknod didn't free locked parent (deadlock) lookup returned real error on create and rename instead of EJUSTRETURN rename changed `.' entry in child instead of name entry in parent rename removed `.' entry in child instead of removing entry in parent when moving a directory from one dir to another createde() left new node locked when write of parent failed (deadlock) removede() decremented refcount even on error (rmdir's which failed due to write errors left in-core cache entries inconsistent) changed validation for filesystem to not check for the boot signature since some disks (e.g., mtools) aren't bootable directories are always show current time as modify time (needed for NFS export since DOS never updates dir mod times -- ctime is true create time). - Added support for cookies changes to the readdir() vnode interface (#ifdef __bsdi__) - Punted on the whole problem of inode generation numbers. This means that there's a chance of using a stale file handle to access a new file, but it doesn't appear to be the common case, and I don't see how to generate reasonable generation numbers without changing something on the disk (which is the way the SVR4 filesystem survival kit guys did it). I don't think it would be very safe to change the on-disk format. Jeff Polk (polk@BSDI.COM) ------------------------------------------------------------------------------
1993-08-13 15:35:13 +04:00
break;
}
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)
brought in fixed/renamed/matching MS-DOS FS code, from Jeff Polk <polk@bsdi.com>. His notes are as follows: ------------------------------------------------------------------------------ July 22, 1993 - Changed name of entire package from PCFS to MSDOSFS - Fixed bugs: root directory size in clusters instead of bytes growing directory didn't update in-core size link, symlink, mknod didn't free locked parent (deadlock) lookup returned real error on create and rename instead of EJUSTRETURN rename changed `.' entry in child instead of name entry in parent rename removed `.' entry in child instead of removing entry in parent when moving a directory from one dir to another createde() left new node locked when write of parent failed (deadlock) removede() decremented refcount even on error (rmdir's which failed due to write errors left in-core cache entries inconsistent) changed validation for filesystem to not check for the boot signature since some disks (e.g., mtools) aren't bootable directories are always show current time as modify time (needed for NFS export since DOS never updates dir mod times -- ctime is true create time). - Added support for cookies changes to the readdir() vnode interface (#ifdef __bsdi__) - Punted on the whole problem of inode generation numbers. This means that there's a chance of using a stale file handle to access a new file, but it doesn't appear to be the common case, and I don't see how to generate reasonable generation numbers without changing something on the disk (which is the way the SVR4 filesystem survival kit guys did it). I don't think it would be very safe to change the on-disk format. Jeff Polk (polk@BSDI.COM) ------------------------------------------------------------------------------
1993-08-13 15:35:13 +04:00
break;
}
brought in fixed/renamed/matching MS-DOS FS code, from Jeff Polk <polk@bsdi.com>. His notes are as follows: ------------------------------------------------------------------------------ July 22, 1993 - Changed name of entire package from PCFS to MSDOSFS - Fixed bugs: root directory size in clusters instead of bytes growing directory didn't update in-core size link, symlink, mknod didn't free locked parent (deadlock) lookup returned real error on create and rename instead of EJUSTRETURN rename changed `.' entry in child instead of name entry in parent rename removed `.' entry in child instead of removing entry in parent when moving a directory from one dir to another createde() left new node locked when write of parent failed (deadlock) removede() decremented refcount even on error (rmdir's which failed due to write errors left in-core cache entries inconsistent) changed validation for filesystem to not check for the boot signature since some disks (e.g., mtools) aren't bootable directories are always show current time as modify time (needed for NFS export since DOS never updates dir mod times -- ctime is true create time). - Added support for cookies changes to the readdir() vnode interface (#ifdef __bsdi__) - Punted on the whole problem of inode generation numbers. This means that there's a chance of using a stale file handle to access a new file, but it doesn't appear to be the common case, and I don't see how to generate reasonable generation numbers without changing something on the disk (which is the way the SVR4 filesystem survival kit guys did it). I don't think it would be very safe to change the on-disk format. Jeff Polk (polk@BSDI.COM) ------------------------------------------------------------------------------
1993-08-13 15:35:13 +04:00
out: ;
uio->uio_resid += lost;
/*
* I don't know why we bother setting this eofflag, getdirentries()
* in vfs_syscalls.c doesn't bother to look at it when we return.
* (because NFS uses it in nfs_serv.c -- JMP)
*/
if (dep->de_FileSize - uio->uio_offset - bias <= 0)
*eofflagp = 1;
else
*eofflagp = 0;
return error;
}
/*
* DOS filesystems don't know what symlinks are.
*/
int
msdosfs_readlink(vp, uio, cred)
struct vnode *vp;
struct uio *uio;
struct ucred *cred;
{
return EINVAL;
}
int
msdosfs_abortop(ndp)
struct nameidata *ndp;
{
if ((ndp->ni_nameiop & (HASBUF | SAVESTART)) == HASBUF)
FREE(ndp->ni_pnbuf, M_NAMEI);
return 0;
}
int
msdosfs_lock(vp)
struct vnode *vp;
{
struct denode *dep = VTODE(vp);
DELOCK(dep);
return 0;
}
int
msdosfs_unlock(vp)
struct vnode *vp;
{
struct denode *dep = VTODE(vp);
if (!(dep->de_flag & DELOCKED))
panic("msdosfs_unlock: denode not locked");
DEUNLOCK(dep);
return 0;
}
int
msdosfs_islocked(vp)
struct vnode *vp;
{
return VTODE(vp)->de_flag & DELOCKED ? 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
*/
int
msdosfs_bmap(vp, bn, vpp, bnp)
struct vnode *vp;
daddr_t bn;
struct vnode **vpp;
daddr_t *bnp;
{
struct denode *dep = VTODE(vp);
struct msdosfsmount *pmp = dep->de_pmp;
if (vpp != NULL)
*vpp = dep->de_devvp;
if (bnp == NULL)
return 0;
return pcbmap(dep, bn << (pmp->pm_cnshift - pmp->pm_bnshift), bnp, 0);
}
int
msdosfs_strategy(bp)
struct buf *bp;
{
struct denode *dep = VTODE(bp->b_vp);
struct msdosfsmount *pmp = dep->de_pmp;
struct vnode *vp;
int error;
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) {
if (error = pcbmap(dep, bp->b_lblkno, &bp->b_blkno, 0))
return error;
if ((long) bp->b_blkno == -1)
clrbuf(bp);
}
if ((long) bp->b_blkno == -1) {
biodone(bp);
return 0;
}
#ifdef DIAGNOSTIC
#endif /* defined(DIAGNOSTIC) */
/*
* Read/write the block from/to the disk that contains the desired
* file block.
*/
vp = dep->de_devvp;
bp->b_dev = vp->v_rdev;
(*(vp->v_op->vop_strategy)) (bp);
return 0;
}
int
msdosfs_print(vp)
struct vnode *vp;
{
struct denode *dep = VTODE(vp);
printf("tag VT_MSDOSFS, startcluster %d, dircluster %d, diroffset %d ",
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 & DELOCKED ? "(LOCKED)" : "");
if (dep->de_spare0) {
printf(" owner pid %d", dep->de_spare0);
if (dep->de_spare1)
printf(" waiting pid %d", dep->de_spare1);
printf("\n");
}
}
int
msdosfs_advlock(vp, id, op, fl, flags)
struct vnode *vp;
caddr_t id;
int op;
struct flock *fl;
int flags;
{
return EINVAL; /* we don't do locking yet */
}
struct vnodeops msdosfs_vnodeops = {
msdosfs_lookup,
msdosfs_create,
msdosfs_mknod,
msdosfs_open,
msdosfs_close,
msdosfs_access,
msdosfs_getattr,
msdosfs_setattr,
msdosfs_read,
msdosfs_write,
msdosfs_ioctl,
msdosfs_select,
msdosfs_mmap,
msdosfs_fsync,
msdosfs_seek,
msdosfs_remove,
msdosfs_link,
msdosfs_rename,
msdosfs_mkdir,
msdosfs_rmdir,
msdosfs_symlink,
msdosfs_readdir,
msdosfs_readlink,
msdosfs_abortop,
msdosfs_inactive,
msdosfs_reclaim,
msdosfs_lock,
msdosfs_unlock,
msdosfs_bmap,
msdosfs_strategy,
msdosfs_print,
msdosfs_islocked,
msdosfs_advlock,
};