/*
* Truncate the file described by dep to the length specified by length.
*/
int
detrunc(struct denode *dep, u_long length, int flags, struct ucred *cred)
{
int error;
int allerror;
u_long eofentry;
u_long chaintofree;
daddr_t bn;
int boff;
int isadir = dep->de_Attributes & ATTR_DIRECTORY;
struct buf *bp;
struct msdosfsmount *pmp = dep->de_pmp;
#ifdef MSDOSFS_DEBUG
printf("detrunc(): file %s, length %lu, flags %x\n", dep->de_Name, length, flags);
#endif
/*
* Disallow attempts to truncate the root directory since it is of
* fixed size. That's just the way dos filesystems are. We use
* the VROOT bit in the vnode because checking for the directory
* bit and a startcluster of 0 in the denode is not adequate to
* recognize the root directory at this point in a file or
* directory's life.
*/
if ((DETOV(dep)->v_vflag & VV_ROOT) && !FAT32(pmp)) {
#ifdef MSDOSFS_DEBUG
printf("detrunc(): can't truncate root directory, clust %ld, offset %ld\n",
dep->de_dirclust, dep->de_diroffset);
#endif
return (EINVAL);
}
if (dep->de_FileSize < length) {
vnode_pager_setsize(DETOV(dep), length);
return deextend(dep, length, cred);
}
/*
* If the desired length is 0 then remember the starting cluster of
* the file and set the StartCluster field in the directory entry
* to 0. If the desired length is not zero, then get the number of
* the last cluster in the shortened file. Then get the number of
* the first cluster in the part of the file that is to be freed.
* Then set the next cluster pointer in the last cluster of the
* file to CLUST_EOFE.
*/
if (length == 0) {
chaintofree = dep->de_StartCluster;
dep->de_StartCluster = 0;
eofentry = ~0;
} else {
error = pcbmap(dep, de_clcount(pmp, length) - 1, 0,
&eofentry, 0);
if (error) {
#ifdef MSDOSFS_DEBUG
printf("detrunc(): pcbmap fails %d\n", error);
#endif
return (error);
}
}
fc_purge(dep, de_clcount(pmp, length));
/*
* If the new length is not a multiple of the cluster size then we
* must zero the tail end of the new last cluster in case it
* becomes part of the file again because of a seek.
*/
if ((boff = length & pmp->pm_crbomask) != 0) {
if (isadir) {
bn = cntobn(pmp, eofentry);
error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster,
NOCRED, &bp);
if (error) {
brelse(bp);
#ifdef MSDOSFS_DEBUG
printf("detrunc(): bread fails %d\n", error);
#endif
return (error);
}
bzero(bp->b_data + boff, pmp->pm_bpcluster - boff);
if (flags & IO_SYNC)
bwrite(bp);
else
bdwrite(bp);
}
}
/*
* Write out the updated directory entry. Even if the update fails
* we free the trailing clusters.
*/
dep->de_FileSize = length;
if (!isadir)
dep->de_flag |= DE_UPDATE | DE_MODIFIED;
allerror = vtruncbuf(DETOV(dep), cred, length, pmp->pm_bpcluster);
#ifdef MSDOSFS_DEBUG
if (allerror)
printf("detrunc(): vtruncbuf error %d\n", allerror);
#endif
error = deupdat(dep, !DOINGASYNC((DETOV(dep))));
if (error != 0 && allerror == 0)
allerror = error;
#ifdef MSDOSFS_DEBUG
printf("detrunc(): allerror %d, eofentry %lu\n",
allerror, eofentry);
#endif
/*
* If we need to break the cluster chain for the file then do it
* now.
*/
if (eofentry != ~0) {
error = fatentry(FAT_GET_AND_SET, pmp, eofentry,
&chaintofree, CLUST_EOFE);
if (error) {
#ifdef MSDOSFS_DEBUG
printf("detrunc(): fatentry errors %d\n", error);
#endif
return (error);
}
fc_setcache(dep, FC_LASTFC, de_cluster(pmp, length - 1),
eofentry);
}
/*
* Now free the clusters removed from the file because of the
* truncation.
*/
if (chaintofree != 0 && !MSDOSFSEOF(pmp, chaintofree))
freeclusterchain(pmp, chaintofree);
return (allerror);
}
/*
* dep - directory entry to copy into the directory
* ddep - directory to add to
* depp - return the address of the denode for the created directory entry
* if depp != 0
* cnp - componentname needed for Win95 long filenames
*/
int
createde(struct denode *dep, struct denode *ddep, struct denode **depp, struct componentname *cnp)
{
int error, rberror;
u_long dirclust, clusoffset;
u_long fndoffset, havecnt = 0, wcnt = 1, i;
struct direntry *ndep;
struct msdosfsmount *pmp = ddep->de_pmp;
struct buf *bp;
daddr_t bn;
int blsize;
#ifdef _KERNEL
int async = ddep->de_pmp->pm_mountp->mnt_flag & MNT_ASYNC;
#else
#define async 0
#endif
#ifdef MSDOSFS_DEBUG
printf("createde(dep %p, ddep %p, depp %p, cnp %p)\n",
dep, ddep, depp, cnp);
#endif
/*
* If no space left in the directory then allocate another cluster
* and chain it onto the end of the file. There is one exception
* to this. That is, if the root directory has no more space it
* can NOT be expanded. extendfile() checks for and fails attempts
* to extend the root directory. We just return an error in that
* case.
*/
if (ddep->de_fndoffset >= ddep->de_FileSize) {
u_long needlen = ddep->de_fndoffset + sizeof(struct direntry)
- ddep->de_FileSize;
dirclust = de_clcount(pmp, needlen);
if ((error = extendfile(ddep, dirclust, 0, 0, DE_CLEAR)) != 0) {
(void)detrunc(ddep, ddep->de_FileSize, 0, NOCRED);
goto err_norollback;
}
/*
* Update the size of the directory
*/
ddep->de_FileSize += de_cn2off(pmp, dirclust);
}
/*
* We just read in the cluster with space. Copy the new directory
* entry in. Then write it to disk. NOTE: DOS directories
* do not get smaller as clusters are emptied.
*/
error = pcbmap(ddep, de_cluster(pmp, ddep->de_fndoffset),
&bn, &dirclust, &blsize);
if (error)
goto err_norollback;
clusoffset = ddep->de_fndoffset;
if (dirclust != MSDOSFSROOT)
clusoffset &= pmp->pm_crbomask;
if ((error = bread(pmp->pm_devvp, de_bn2kb(pmp, bn), blsize, NOCRED,
B_MODIFY, &bp)) != 0) {
goto err_norollback;
}
ndep = bptoep(pmp, bp, clusoffset);
DE_EXTERNALIZE(ndep, dep);
/*
* Now write the Win95 long name
*/
if (ddep->de_fndcnt > 0) {
u_int8_t chksum = winChksum(ndep->deName);
const u_char *un = (const u_char *)cnp->cn_nameptr;
int unlen = cnp->cn_namelen;
u_long xhavecnt;
fndoffset = ddep->de_fndoffset;
xhavecnt = ddep->de_fndcnt + 1;
for(; wcnt < xhavecnt; wcnt++) {
if ((fndoffset & pmp->pm_crbomask) == 0) {
/* we should never get here if ddep is root
* directory */
if (async)
(void) bdwrite(bp);
else if ((error = bwrite(bp)) != 0)
goto rollback;
fndoffset -= sizeof(struct direntry);
error = pcbmap(ddep,
de_cluster(pmp, fndoffset),
&bn, 0, &blsize);
if (error)
goto rollback;
error = bread(pmp->pm_devvp, de_bn2kb(pmp, bn),
blsize, NOCRED, B_MODIFY, &bp);
if (error) {
goto rollback;
}
ndep = bptoep(pmp, bp,
fndoffset & pmp->pm_crbomask);
} else {
ndep--;
fndoffset -= sizeof(struct direntry);
}
if (!unix2winfn(un, unlen, (struct winentry *)ndep,
wcnt, chksum))
break;
}
}
if (async)
bdwrite(bp);
else if ((error = bwrite(bp)) != 0)
goto rollback;
/*
* If they want us to return with the denode gotten.
*/
if (depp) {
u_long diroffset = clusoffset;
if (dep->de_Attributes & ATTR_DIRECTORY) {
dirclust = dep->de_StartCluster;
if (FAT32(pmp) && dirclust == pmp->pm_rootdirblk)
dirclust = MSDOSFSROOT;
if (dirclust == MSDOSFSROOT)
diroffset = MSDOSFSROOT_OFS;
else
diroffset = 0;
}
error = deget(pmp, dirclust, diroffset, depp);
#ifndef MAKEFS
if (error == 0)
VOP_UNLOCK(DETOV(*depp));
#endif
return error;
}
return 0;
rollback:
/*
* Mark all slots modified so far as deleted. Note that we
* can't just call removede(), since directory is not in
* consistent state.
*/
fndoffset = ddep->de_fndoffset;
rberror = pcbmap(ddep, de_cluster(pmp, fndoffset),
&bn, NULL, &blsize);
if (rberror)
goto err_norollback;
if ((rberror = bread(pmp->pm_devvp, de_bn2kb(pmp, bn), blsize, NOCRED,
B_MODIFY, &bp)) != 0) {
goto err_norollback;
}
ndep = bptoep(pmp, bp, clusoffset);
havecnt = ddep->de_fndcnt + 1;
for(i = wcnt; i <= havecnt; i++) {
/* mark entry as deleted */
ndep->deName[0] = SLOT_DELETED;
if ((fndoffset & pmp->pm_crbomask) == 0) {
/* we should never get here if ddep is root
* directory */
if (async)
bdwrite(bp);
else if ((rberror = bwrite(bp)) != 0)
goto err_norollback;
fndoffset -= sizeof(struct direntry);
rberror = pcbmap(ddep,
de_cluster(pmp, fndoffset),
&bn, 0, &blsize);
if (rberror)
goto err_norollback;
rberror = bread(pmp->pm_devvp, de_bn2kb(pmp, bn),
blsize, NOCRED, B_MODIFY, &bp);
if (rberror) {
goto err_norollback;
}
ndep = bptoep(pmp, bp, fndoffset);
} else {
ndep--;
fndoffset -= sizeof(struct direntry);
}
}
/* ignore any further error */
if (async)
(void) bdwrite(bp);
else
(void) bwrite(bp);
err_norollback:
return error;
}
/*
* Remove a directory entry. At this point the file represented by the
* directory entry to be removed is still full length until noone has it
* open. When the file no longer being used msdosfs_inactive() is called
* and will truncate the file to 0 length. When the vnode containing the
* denode is needed for some other purpose by VFS it will call
* msdosfs_reclaim() which will remove the denode from the denode cache.
*/
int
removede(struct denode *pdep, struct denode *dep)
/* pdep: directory where the entry is removed */
/* dep: file to be removed */
{
int error;
struct direntry *ep;
struct buf *bp;
daddr_t bn;
int blsize;
struct msdosfsmount *pmp = pdep->de_pmp;
u_long offset = pdep->de_fndoffset;
#ifdef _KERNEL
int async = pdep->de_pmp->pm_mountp->mnt_flag & MNT_ASYNC;
#else
#define async 0
#endif
#ifdef MSDOSFS_DEBUG
printf("removede(): filename %s, dep %p, offset %08lx\n",
dep->de_Name, dep, offset);
#endif
dep->de_refcnt--;
offset += sizeof(struct direntry);
do {
offset -= sizeof(struct direntry);
error = pcbmap(pdep, de_cluster(pmp, offset), &bn, 0, &blsize);
if (error)
return error;
error = bread(pmp->pm_devvp, de_bn2kb(pmp, bn), blsize, NOCRED,
B_MODIFY, &bp);
if (error) {
return error;
}
ep = bptoep(pmp, bp, offset);
/*
* Check whether, if we came here the second time, i.e.
* when underflowing into the previous block, the last
* entry in this block is a longfilename entry, too.
*/
if (ep->deAttributes != ATTR_WIN95
&& offset != pdep->de_fndoffset) {
brelse(bp, 0);
break;
}
offset += sizeof(struct direntry);
while (1) {
/*
* We are a bit agressive here in that we delete any Win95
* entries preceding this entry, not just the ones we "own".
* Since these presumably aren't valid anyway,
* there should be no harm.
*/
offset -= sizeof(struct direntry);
ep--->deName[0] = SLOT_DELETED;
if ((pmp->pm_flags & MSDOSFSMNT_NOWIN95)
|| !(offset & pmp->pm_crbomask)
|| ep->deAttributes != ATTR_WIN95)
break;
}
if (async)
bdwrite(bp);
else if ((error = bwrite(bp)) != 0)
return error;
} while (!(pmp->pm_flags & MSDOSFSMNT_NOWIN95)
&& !(offset & pmp->pm_crbomask)
&& offset);
return 0;
}
/*
* dep - directory entry to copy into the directory
* ddep - directory to add to
* depp - return the address of the denode for the created directory entry
* if depp != 0
* cnp - componentname needed for Win95 long filenames
*/
int
createde(struct denode *dep, struct denode *ddep, struct denode **depp,
struct componentname *cnp)
{
int error;
u_long dirclust, diroffset;
struct direntry *ndep;
struct msdosfsmount *pmp = ddep->de_pmp;
struct buf *bp;
daddr_t bn;
int blsize;
#ifdef MSDOSFS_DEBUG
kprintf("createde(dep %p, ddep %p, depp %p, cnp %p)\n",
dep, ddep, depp, cnp);
#endif
/*
* If no space left in the directory then allocate another cluster
* and chain it onto the end of the file. There is one exception
* to this. That is, if the root directory has no more space it
* can NOT be expanded. extendfile() checks for and fails attempts
* to extend the root directory. We just return an error in that
* case.
*/
if (ddep->de_fndoffset >= ddep->de_FileSize) {
diroffset = ddep->de_fndoffset + sizeof(struct direntry)
- ddep->de_FileSize;
dirclust = de_clcount(pmp, diroffset);
error = extendfile(ddep, dirclust, 0, 0, DE_CLEAR);
if (error) {
detrunc(ddep, ddep->de_FileSize, 0);
return error;
}
/*
* Update the size of the directory
*/
ddep->de_FileSize += de_cn2off(pmp, dirclust);
}
/*
* We just read in the cluster with space. Copy the new directory
* entry in. Then write it to disk. NOTE: DOS directories
* do not get smaller as clusters are emptied.
*/
error = pcbmap(ddep, de_cluster(pmp, ddep->de_fndoffset),
&bn, &dirclust, &blsize);
if (error)
return error;
diroffset = ddep->de_fndoffset;
if (dirclust != MSDOSFSROOT)
diroffset &= pmp->pm_crbomask;
if ((error = bread(pmp->pm_devvp, de_bntodoff(pmp, bn), blsize, &bp)) != 0) {
brelse(bp);
return error;
}
ndep = bptoep(pmp, bp, ddep->de_fndoffset);
DE_EXTERNALIZE(ndep, dep);
/*
* Now write the Win95 long name
*/
if (ddep->de_fndcnt > 0) {
u_int8_t chksum = winChksum(ndep->deName);
const u_char *un = (const u_char *)cnp->cn_nameptr;
int unlen = cnp->cn_namelen;
int cnt = 1;
while (--ddep->de_fndcnt >= 0) {
if (!(ddep->de_fndoffset & pmp->pm_crbomask)) {
if ((error = bwrite(bp)) != 0)
return error;
ddep->de_fndoffset -= sizeof(struct direntry);
error = pcbmap(ddep,
de_cluster(pmp,
ddep->de_fndoffset),
&bn, NULL, &blsize);
if (error)
return error;
error = bread(pmp->pm_devvp, de_bntodoff(pmp, bn), blsize, &bp);
if (error) {
brelse(bp);
return error;
}
ndep = bptoep(pmp, bp, ddep->de_fndoffset);
} else {
ndep--;
ddep->de_fndoffset -= sizeof(struct direntry);
}
if (!unix2winfn(un, unlen, (struct winentry *)ndep,
cnt++, chksum,
pmp))
break;
}
}
if ((error = bwrite(bp)) != 0)
return error;
/*
* If they want us to return with the denode gotten.
*/
if (depp) {
if (dep->de_Attributes & ATTR_DIRECTORY) {
dirclust = dep->de_StartCluster;
if (FAT32(pmp) && dirclust == pmp->pm_rootdirblk)
dirclust = MSDOSFSROOT;
if (dirclust == MSDOSFSROOT)
diroffset = MSDOSFSROOT_OFS;
else
diroffset = 0;
}
return deget(pmp, dirclust, diroffset, depp);
}
return 0;
}
/*
* 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
* componentname structures is freed, there may be some memory bleeding
* for each rename done.
*/
int
msdosfs_rename(void *v)
{
struct vop_rename_args *ap = v;
struct vnode *tvp = ap->a_tvp;
struct vnode *tdvp = ap->a_tdvp;
struct vnode *fvp = ap->a_fvp;
struct vnode *fdvp = ap->a_fdvp;
struct componentname *tcnp = ap->a_tcnp;
struct componentname *fcnp = ap->a_fcnp;
struct proc *p = curproc; /* XXX */
struct denode *ip, *xp, *dp, *zp;
u_char toname[11], oldname[11];
uint32_t from_diroffset, to_diroffset;
u_char to_count;
int doingdirectory = 0, newparent = 0;
int error;
uint32_t cn, pcl;
daddr64_t bn;
struct msdosfsmount *pmp;
struct direntry *dotdotp;
struct buf *bp;
pmp = VFSTOMSDOSFS(fdvp->v_mount);
#ifdef DIAGNOSTIC
if ((tcnp->cn_flags & HASBUF) == 0 ||
(fcnp->cn_flags & HASBUF) == 0)
panic("msdosfs_rename: no name");
#endif
/*
* Check for cross-device rename.
*/
if ((fvp->v_mount != tdvp->v_mount) ||
(tvp && (fvp->v_mount != tvp->v_mount))) {
error = EXDEV;
abortit:
VOP_ABORTOP(tdvp, tcnp);
if (tdvp == tvp)
vrele(tdvp);
else
vput(tdvp);
if (tvp)
vput(tvp);
VOP_ABORTOP(fdvp, fcnp);
vrele(fdvp);
vrele(fvp);
return (error);
}
/*
* If source and dest are the same, do nothing.
*/
if (tvp == fvp) {
error = 0;
goto abortit;
}
/* */
if ((error = vn_lock(fvp, LK_EXCLUSIVE | LK_RETRY, p)) != 0)
goto abortit;
dp = VTODE(fdvp);
ip = VTODE(fvp);
/*
* 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 (ip->de_Attributes & ATTR_DIRECTORY) {
/*
* Avoid ".", "..", and aliases of "." for obvious reasons.
*/
if ((fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.') ||
dp == ip ||
(fcnp->cn_flags & ISDOTDOT) ||
(tcnp->cn_flags & ISDOTDOT) ||
(ip->de_flag & DE_RENAME)) {
VOP_UNLOCK(fvp, 0, p);
error = EINVAL;
goto abortit;
}
ip->de_flag |= DE_RENAME;
doingdirectory++;
}
/*
* When the target exists, both the directory
* and target vnodes are returned locked.
*/
dp = VTODE(tdvp);
xp = tvp ? VTODE(tvp) : NULL;
/*
* Remember direntry place to use for destination
*/
to_diroffset = dp->de_fndoffset;
to_count = dp->de_fndcnt;
/*
* If ".." must be changed (ie the directory gets a new
* parent) then the source directory must not be in the
* directory hierarchy above the target, as this would
* orphan everything below the source directory. Also
* the user must have write permission in the source so
* as to be able to change "..". We must repeat the call
* to namei, as the parent directory is unlocked by the
* call to doscheckpath().
*/
error = VOP_ACCESS(fvp, VWRITE, tcnp->cn_cred, tcnp->cn_proc);
VOP_UNLOCK(fvp, 0, p);
if (VTODE(fdvp)->de_StartCluster != VTODE(tdvp)->de_StartCluster)
newparent = 1;
vrele(fdvp);
if (doingdirectory && newparent) {
if (error) /* write access check above */
goto bad1;
if (xp != NULL)
vput(tvp);
/*
* doscheckpath() vput()'s dp,
* so we have to do a relookup afterwards
*/
if ((error = doscheckpath(ip, dp)) != 0)
goto out;
if ((tcnp->cn_flags & SAVESTART) == 0)
panic("msdosfs_rename: lost to startdir");
if ((error = vfs_relookup(tdvp, &tvp, tcnp)) != 0)
goto out;
dp = VTODE(tdvp);
xp = tvp ? VTODE(tvp) : NULL;
}
if (xp != NULL) {
/*
* Target must be empty if a directory and have no links
* to it. Also, ensure source and target are compatible
* (both directories, or both not directories).
*/
if (xp->de_Attributes & ATTR_DIRECTORY) {
if (!dosdirempty(xp)) {
error = ENOTEMPTY;
goto bad1;
}
if (!doingdirectory) {
error = ENOTDIR;
goto bad1;
}
cache_purge(tdvp);
} else if (doingdirectory) {
error = EISDIR;
goto bad1;
}
if ((error = removede(dp, xp)) != 0)
goto bad1;
vput(tvp);
xp = NULL;
}
/*
* Convert the filename in tcnp into a dos filename. We copy this
* into the denode and directory entry for the destination
* file/directory.
*/
if ((error = uniqdosname(VTODE(tdvp), tcnp, toname)) != 0)
goto bad1;
/*
* Since from wasn't locked at various places above,
* have to do a relookup here.
*/
fcnp->cn_flags &= ~MODMASK;
fcnp->cn_flags |= LOCKPARENT | LOCKLEAF;
if ((fcnp->cn_flags & SAVESTART) == 0)
panic("msdosfs_rename: lost from startdir");
if (!newparent)
VOP_UNLOCK(tdvp, 0, p);
(void) vfs_relookup(fdvp, &fvp, fcnp);
if (fvp == NULL) {
/*
* From name has disappeared.
*/
if (doingdirectory)
panic("rename: lost dir entry");
vrele(ap->a_fvp);
if (newparent)
VOP_UNLOCK(tdvp, 0, p);
vrele(tdvp);
return 0;
}
xp = VTODE(fvp);
zp = VTODE(fdvp);
from_diroffset = zp->de_fndoffset;
/*
* Ensure that the directory entry still exists and has not
* changed till now. If the source is a file the entry may
* have been unlinked or renamed. In either case there is
* no further work to be done. If the source is a directory
* then it cannot have been rmdir'ed or renamed; this is
* prohibited by the DE_RENAME flag.
*/
if (xp != ip) {
if (doingdirectory)
panic("rename: lost dir entry");
vrele(ap->a_fvp);
if (newparent)
VOP_UNLOCK(fdvp, 0, p);
xp = NULL;
} else {
vrele(fvp);
xp = NULL;
/*
* First write a new entry in the destination
* directory and mark the entry in the source directory
* as deleted. 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.
*/
bcopy(ip->de_Name, oldname, 11);
bcopy(toname, ip->de_Name, 11); /* update denode */
dp->de_fndoffset = to_diroffset;
dp->de_fndcnt = to_count;
error = createde(ip, dp, (struct denode **)0, tcnp);
if (error) {
bcopy(oldname, ip->de_Name, 11);
if (newparent)
VOP_UNLOCK(fdvp, 0, p);
goto bad;
}
ip->de_refcnt++;
zp->de_fndoffset = from_diroffset;
if ((error = removede(zp, ip)) != 0) {
/* XXX should really panic here, fs is corrupt */
if (newparent)
VOP_UNLOCK(fdvp, 0, p);
goto bad;
}
cache_purge(fvp);
if (!doingdirectory) {
error = pcbmap(dp, de_cluster(pmp, to_diroffset), 0,
&ip->de_dirclust, 0);
if (error) {
/* XXX should really panic here, fs is corrupt */
if (newparent)
VOP_UNLOCK(fdvp, 0, p);
goto bad;
}
if (ip->de_dirclust != MSDOSFSROOT)
ip->de_diroffset = to_diroffset & pmp->pm_crbomask;
}
reinsert(ip);
if (newparent)
VOP_UNLOCK(fdvp, 0, p);
}
/*
* If we moved a directory to a new parent directory, then we must
* fixup the ".." entry in the moved directory.
*/
if (doingdirectory && newparent) {
cn = ip->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) {
/* XXX should really panic here, fs is corrupt */
brelse(bp);
goto bad;
}
dotdotp = (struct direntry *)bp->b_data;
putushort(dotdotp[0].deStartCluster, cn);
pcl = dp->de_StartCluster;
if (FAT32(pmp) && pcl == pmp->pm_rootdirblk)
pcl = 0;
putushort(dotdotp[1].deStartCluster, pcl);
if (FAT32(pmp)) {
putushort(dotdotp[0].deHighClust, cn >> 16);
putushort(dotdotp[1].deHighClust, pcl >> 16);
}
if ((error = bwrite(bp)) != 0) {
/* XXX should really panic here, fs is corrupt */
goto bad;
}
}
/*
* Write data to a file or directory.
*/
int
msdosfs_write(void *v)
{
struct vop_write_args *ap = v;
int n;
int croffset;
int resid;
uint32_t osize;
int error = 0;
uint32_t count, lastcn;
daddr64_t bn;
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;
#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;
thisvp = vp;
break;
case VDIR:
return EISDIR;
default:
panic("msdosfs_write(): bad file type");
}
if (uio->uio_offset < 0)
return (EINVAL);
if (uio->uio_resid == 0)
return (0);
/* Don't bother to try to write files larger than the f/s limit */
if (uio->uio_offset + uio->uio_resid > MSDOSFS_FILESIZE_MAX)
return (EFBIG);
/*
* If they've exceeded their filesize limit, tell them about it.
*/
if (p &&
((uio->uio_offset + uio->uio_resid) >
p->p_rlimit[RLIMIT_FSIZE].rlim_cur)) {
psignal(p, SIGXFSZ);
return (EFBIG);
}
/*
* 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) {
if ((error = deextend(dep, uio->uio_offset, cred)) != 0)
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 {
if (de_cluster(pmp, uio->uio_offset) > lastcn) {
error = ENOSPC;
break;
}
bn = de_blk(pmp, uio->uio_offset);
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 (bp->b_blkno == bp->b_lblkno) {
error = pcbmap(dep,
de_bn2cn(pmp, bp->b_lblkno),
&bp->b_blkno, 0, 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,
NOCRED, &bp);
if (error) {
brelse(bp);
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;
uvm_vnp_setsize(vp, dep->de_FileSize);
}
uvm_vnp_uncache(vp);
/*
* 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 if (ioflag & IO_SYNC)
error = deupdat(dep, 1);
return (error);
}
int
msdosfs_read(void *v)
{
struct vop_read_args *ap = v;
int error = 0;
uint32_t diff;
int blsize;
int isadir;
uint32_t n;
long on;
daddr64_t lbn, rablock, rablkno;
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 {
if (uio->uio_offset >= dep->de_FileSize)
return (0);
lbn = de_cluster(pmp, uio->uio_offset);
on = uio->uio_offset & pmp->pm_crbomask;
n = min((uint32_t) (pmp->pm_bpcluster - on), uio->uio_resid);
/*
* de_FileSize is uint32_t, and we know that uio_offset <
* de_FileSize, so uio->uio_offset < 2^32. Therefore
* the cast to uint32_t on the next line is safe.
*/
diff = dep->de_FileSize - (uint32_t)uio->uio_offset;
if (diff < n)
n = diff;
/* convert cluster # to block # if a directory */
if (isadir) {
error = pcbmap(dep, lbn, &lbn, 0, &blsize);
if (error)
return (error);
}
/*
* 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, blsize, NOCRED, &bp);
} else {
rablock = lbn + 1;
rablkno = de_cn2bn(pmp, rablock);
if (dep->de_lastr + 1 == lbn &&
de_cn2off(pmp, rablock) < dep->de_FileSize)
error = breadn(vp, de_cn2bn(pmp, lbn),
pmp->pm_bpcluster, &rablkno,
&pmp->pm_bpcluster, 1, NOCRED, &bp);
else
error = bread(vp, de_cn2bn(pmp, lbn),
pmp->pm_bpcluster, NOCRED, &bp);
dep->de_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);
brelse(bp);
} while (error == 0 && uio->uio_resid > 0 && n != 0);
if (!isadir && !(vp->v_mount->mnt_flag & MNT_NOATIME))
dep->de_flag |= DE_ACCESS;
return (error);
}
int
msdosfs_readdir(void *v)
{
struct vop_readdir_args *ap = v;
int error = 0;
int diff;
long n;
int blsize;
long on;
long lost;
long count;
uint32_t dirsperblk;
uint32_t cn, lbn;
uint32_t fileno;
long bias = 0;
daddr64_t bn;
struct buf *bp;
struct denode *dep = VTODE(ap->a_vp);
struct msdosfsmount *pmp = dep->de_pmp;
struct direntry *dentp;
struct dirent dirbuf;
struct uio *uio = ap->a_uio;
u_long *cookies = NULL;
int ncookies = 0;
off_t offset, wlast = -1;
int chksum = -1;
#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 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);
/*
* To be safe, initialize dirbuf
*/
bzero(dirbuf.d_name, sizeof(dirbuf.d_name));
/*
* 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);
offset = uio->uio_offset;
if (count < sizeof(struct direntry) ||
(offset & (sizeof(struct direntry) - 1)))
return (EINVAL);
lost = uio->uio_resid - count;
uio->uio_resid = count;
if (ap->a_ncookies) {
ncookies = uio->uio_resid / sizeof(struct direntry) + 3;
cookies = malloc(ncookies * sizeof(u_long), M_TEMP, M_WAITOK);
*ap->a_cookies = cookies;
*ap->a_ncookies = ncookies;
}
dirsperblk = pmp->pm_BytesPerSec / sizeof(struct direntry);
/*
* 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
|| (FAT32(pmp) && dep->de_StartCluster == pmp->pm_rootdirblk)) {
#if 0
printf("msdosfs_readdir(): going after . or .. in root dir, offset %d\n",
offset);
#endif
bias = 2 * sizeof(struct direntry);
if (offset < bias) {
for (n = (int)offset / sizeof(struct direntry);
n < 2; n++) {
if (FAT32(pmp))
dirbuf.d_fileno = pmp->pm_rootdirblk;
else
dirbuf.d_fileno = 1;
dirbuf.d_type = DT_DIR;
switch (n) {
case 0:
dirbuf.d_namlen = 1;
strlcpy(dirbuf.d_name, ".",
sizeof dirbuf.d_name);
break;
case 1:
dirbuf.d_namlen = 2;
strlcpy(dirbuf.d_name, "..",
sizeof dirbuf.d_name);
break;
}
dirbuf.d_reclen = DIRENT_SIZE(&dirbuf);
if (uio->uio_resid < dirbuf.d_reclen)
goto out;
error = uiomove((caddr_t) &dirbuf,
dirbuf.d_reclen, uio);
if (error)
goto out;
offset += sizeof(struct direntry);
if (cookies) {
*cookies++ = offset;
if (--ncookies <= 0)
goto out;
}
}
}
}
while (uio->uio_resid > 0) {
lbn = de_cluster(pmp, offset - bias);
on = (offset - bias) & pmp->pm_crbomask;
n = min(pmp->pm_bpcluster - on, uio->uio_resid);
diff = dep->de_FileSize - (offset - bias);
if (diff <= 0)
break;
n = min(n, diff);
if ((error = pcbmap(dep, lbn, &bn, &cn, &blsize)) != 0)
break;
error = bread(pmp->pm_devvp, bn, blsize, NOCRED, &bp);
if (error) {
brelse(bp);
return (error);
}
n = min(n, blsize - bp->b_resid);
/*
* Convert from dos directory entries to fs-independent
* directory entries.
*/
for (dentp = (struct direntry *)(bp->b_data + on);
(char *)dentp < bp->b_data + on + n;
dentp++, offset += sizeof(struct direntry)) {
#if 0
printf("rd: dentp %08x prev %08x crnt %08x deName %02x attr %02x\n",
dentp, prev, crnt, dentp->deName[0], dentp->deAttributes);
#endif
/*
* If this is an unused entry, we can stop.
*/
if (dentp->deName[0] == SLOT_EMPTY) {
brelse(bp);
goto out;
}
/*
* Skip deleted entries.
*/
if (dentp->deName[0] == SLOT_DELETED) {
chksum = -1;
wlast = -1;
continue;
}
/*
* Handle Win95 long directory entries
*/
if (dentp->deAttributes == ATTR_WIN95) {
struct winentry *wep;
if (pmp->pm_flags & MSDOSFSMNT_SHORTNAME)
continue;
wep = (struct winentry *)dentp;
chksum = win2unixfn(wep, &dirbuf, chksum);
if (wep->weCnt & WIN_LAST)
wlast = offset;
continue;
}
/*
* Skip volume labels
*/
if (dentp->deAttributes & ATTR_VOLUME) {
chksum = -1;
wlast = -1;
continue;
}
/*
* This computation of d_fileno must match
* the computation of va_fileid in
* msdosfs_getattr.
*/
fileno = getushort(dentp->deStartCluster);
if (FAT32(pmp))
fileno |= getushort(dentp->deHighClust) << 16;
if (dentp->deAttributes & ATTR_DIRECTORY) {
/* Special-case root */
if (fileno == MSDOSFSROOT) {
fileno = FAT32(pmp) ?
pmp->pm_rootdirblk : 1;
}
dirbuf.d_fileno = fileno;
dirbuf.d_type = DT_DIR;
} else {
if (getulong(dentp->deFileSize) == 0) {
uint64_t fileno64;
fileno64 = (cn == MSDOSFSROOT) ?
roottobn(pmp, 0) : cntobn(pmp, cn);
fileno64 *= dirsperblk;
fileno64 += dentp -
(struct direntry *)bp->b_data;
fileno = fileidhash(fileno64);
}
dirbuf.d_fileno = fileno;
dirbuf.d_type = DT_REG;
}
if (chksum != winChksum(dentp->deName))
dirbuf.d_namlen = dos2unixfn(dentp->deName,
(u_char *)dirbuf.d_name,
pmp->pm_flags & MSDOSFSMNT_SHORTNAME);
else
dirbuf.d_name[dirbuf.d_namlen] = 0;
chksum = -1;
dirbuf.d_reclen = DIRENT_SIZE(&dirbuf);
if (uio->uio_resid < dirbuf.d_reclen) {
brelse(bp);
/* Remember long-name offset. */
if (wlast != -1)
offset = wlast;
goto out;
}
wlast = -1;
error = uiomove((caddr_t) &dirbuf,
dirbuf.d_reclen, uio);
if (error) {
brelse(bp);
goto out;
}
if (cookies) {
*cookies++ = offset + sizeof(struct direntry);
if (--ncookies <= 0) {
brelse(bp);
goto out;
}
}
}
brelse(bp);
}
out:
/* Subtract unused cookies */
if (ap->a_ncookies)
*ap->a_ncookies -= ncookies;
uio->uio_offset = offset;
uio->uio_resid += lost;
if (dep->de_FileSize - (offset - bias) <= 0)
*ap->a_eofflag = 1;
else
*ap->a_eofflag = 0;
return (error);
}
