/*
* Check to see if the directory described by target is in some
* subdirectory of source. This prevents something like the following from
* succeeding and leaving a bunch or files and directories orphaned. mv
* /a/b/c /a/b/c/d/e/f Where c and f are directories.
*
* source - the inode for /a/b/c
* target - the inode for /a/b/c/d/e/f
*
* Returns 0 if target is NOT a subdirectory of source.
* Otherwise returns a non-zero error number.
* The target inode is always unlocked on return.
*/
int
doscheckpath(struct denode *source, struct denode *target)
{
u_long scn;
struct msdosfsmount *pmp;
struct direntry *ep;
struct denode *dep;
struct buf *bp = NULL;
int error = 0;
dep = target;
if ((target->de_Attributes & ATTR_DIRECTORY) == 0 ||
(source->de_Attributes & ATTR_DIRECTORY) == 0) {
error = ENOTDIR;
goto out;
}
if (dep->de_StartCluster == source->de_StartCluster) {
error = EEXIST;
goto out;
}
if (dep->de_StartCluster == MSDOSFSROOT)
goto out;
pmp = dep->de_pmp;
#ifdef DIAGNOSTIC
if (pmp != source->de_pmp)
panic("doscheckpath: source and target on different filesystems");
#endif
if (FAT32(pmp) && dep->de_StartCluster == pmp->pm_rootdirblk)
goto out;
for (;;) {
if ((dep->de_Attributes & ATTR_DIRECTORY) == 0) {
error = ENOTDIR;
break;
}
scn = dep->de_StartCluster;
error = bread(pmp->pm_devvp, de_bn2kb(pmp, cntobn(pmp, scn)),
pmp->pm_bpcluster, NOCRED, 0, &bp);
if (error)
break;
ep = (struct direntry *) bp->b_data + 1;
if ((ep->deAttributes & ATTR_DIRECTORY) == 0 ||
memcmp(ep->deName, ".. ", 11) != 0) {
error = ENOTDIR;
break;
}
scn = getushort(ep->deStartCluster);
if (FAT32(pmp))
scn |= getushort(ep->deHighClust) << 16;
if (scn == source->de_StartCluster) {
error = EINVAL;
break;
}
if (scn == MSDOSFSROOT)
break;
if (FAT32(pmp) && scn == pmp->pm_rootdirblk) {
/*
* scn should be 0 in this case,
* but we silently ignore the error.
*/
break;
}
vput(DETOV(dep));
brelse(bp, 0);
bp = NULL;
/* NOTE: deget() clears dep on error */
if ((error = deget(pmp, scn, 0, &dep)) != 0)
break;
}
out:
if (bp)
brelse(bp, 0);
if (error == ENOTDIR)
printf("doscheckpath(): .. not a directory?\n");
if (dep != NULL)
vput(DETOV(dep));
return (error);
}
/*
* 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);
}
/*
* Write data to a file or directory.
*/
static int
msdosfs_wfile(const char *path, struct denode *dep, fsnode *node)
{
int error, fd;
size_t osize = dep->de_FileSize;
struct stat *st = &node->inode->st;
size_t nsize, offs;
struct msdosfsmount *pmp = dep->de_pmp;
struct buf *bp;
char *dat;
u_long cn = 0;
error = 0; /* XXX: gcc/vax */
DPRINTF(("%s(diroff %lu, dirclust %lu, startcluster %lu)\n", __func__,
dep->de_diroffset, dep->de_dirclust, dep->de_StartCluster));
if (st->st_size == 0)
return 0;
/* Don't bother to try to write files larger than the fs limit */
if (st->st_size > MSDOSFS_FILESIZE_MAX) {
errno = EFBIG;
return -1;
}
nsize = st->st_size;
DPRINTF(("%s(nsize=%zu, osize=%zu)\n", __func__, nsize, osize));
if (nsize > osize) {
if ((error = deextend(dep, nsize, NULL)) != 0) {
errno = error;
return -1;
}
if ((error = msdosfs_updatede(dep)) != 0) {
errno = error;
return -1;
}
}
if ((fd = open(path, O_RDONLY)) == -1)
err(1, "open %s", path);
if ((dat = mmap(0, nsize, PROT_READ, MAP_FILE | MAP_PRIVATE, fd, 0))
== MAP_FAILED) {
DPRINTF(("%s: mmap %s %s", __func__, node->name,
strerror(errno)));
close(fd);
goto out;
}
close(fd);
for (offs = 0; offs < nsize;) {
int blsize, cpsize;
daddr_t bn;
u_long on = offs & pmp->pm_crbomask;
#ifdef HACK
cn = dep->de_StartCluster;
if (cn == MSDOSFSROOT) {
DPRINTF(("%s: bad lbn %lu", __func__, cn));
goto out;
}
bn = cntobn(pmp, cn);
blsize = pmp->pm_bpcluster;
#else
if ((error = pcbmap(dep, cn++, &bn, NULL, &blsize)) != 0) {
DPRINTF(("%s: pcbmap %lu", __func__, bn));
goto out;
}
#endif
DPRINTF(("%s(cn=%lu, bn=%llu/%llu, blsize=%d)\n", __func__,
cn, (unsigned long long)bn,
(unsigned long long)de_bn2kb(pmp, bn), blsize));
if ((error = bread(pmp->pm_devvp, de_bn2kb(pmp, bn), blsize,
0, &bp)) != 0) {
DPRINTF(("bread %d\n", error));
goto out;
}
cpsize = MIN((nsize - offs), blsize - on);
memcpy((char *)bp->b_data + on, dat + offs, cpsize);
bwrite(bp);
offs += cpsize;
}
munmap(dat, nsize);
return 0;
out:
munmap(dat, nsize);
return error;
}
struct denode *
msdosfs_mkdire(const char *path, struct denode *pdep, fsnode *node) {
struct denode ndirent;
struct denode *dep;
struct componentname cn;
struct stat *st = &node->inode->st;
struct msdosfsmount *pmp = pdep->de_pmp;
int error;
u_long newcluster, pcl, bn;
daddr_t lbn;
struct direntry *denp;
struct buf *bp;
cn.cn_nameptr = node->name;
cn.cn_namelen = strlen(node->name);
/*
* If this is the root directory and there is no space left we
* can't do anything. This is because the root directory can not
* change size.
*/
if (pdep->de_StartCluster == MSDOSFSROOT
&& pdep->de_fndoffset >= pdep->de_FileSize) {
error = ENOSPC;
goto bad2;
}
/*
* Allocate a cluster to hold the about to be created directory.
*/
error = clusteralloc(pmp, 0, 1, &newcluster, NULL);
if (error)
goto bad2;
memset(&ndirent, 0, sizeof(ndirent));
ndirent.de_pmp = pmp;
ndirent.de_flag = DE_ACCESS | DE_CREATE | DE_UPDATE;
msdosfs_times(pmp, &ndirent, st);
/*
* 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);
lbn = de_bn2kb(pmp, bn);
DPRINTF(("%s(newcluster %lu, bn=%lu, lbn=%lu)\n", __func__, newcluster,
bn, lbn));
/* always succeeds */
bp = getblk(pmp->pm_devvp, lbn, pmp->pm_bpcluster, 0, 0);
memset(bp->b_data, 0, pmp->pm_bpcluster);
memcpy(bp->b_data, &dosdirtemplate, sizeof dosdirtemplate);
denp = (struct direntry *)bp->b_data;
putushort(denp[0].deStartCluster, newcluster);
putushort(denp[0].deCDate, ndirent.de_CDate);
putushort(denp[0].deCTime, ndirent.de_CTime);
denp[0].deCHundredth = ndirent.de_CHun;
putushort(denp[0].deADate, ndirent.de_ADate);
putushort(denp[0].deMDate, ndirent.de_MDate);
putushort(denp[0].deMTime, ndirent.de_MTime);
pcl = pdep->de_StartCluster;
DPRINTF(("%s(pcl %lu, rootdirblk=%lu)\n", __func__, pcl,
pmp->pm_rootdirblk));
if (FAT32(pmp) && pcl == pmp->pm_rootdirblk)
pcl = 0;
putushort(denp[1].deStartCluster, pcl);
putushort(denp[1].deCDate, ndirent.de_CDate);
putushort(denp[1].deCTime, ndirent.de_CTime);
denp[1].deCHundredth = ndirent.de_CHun;
putushort(denp[1].deADate, ndirent.de_ADate);
putushort(denp[1].deMDate, ndirent.de_MDate);
putushort(denp[1].deMTime, ndirent.de_MTime);
if (FAT32(pmp)) {
putushort(denp[0].deHighClust, newcluster >> 16);
putushort(denp[1].deHighClust, pdep->de_StartCluster >> 16);
} else {
int
msdosfs_filestat(kvm_t *kd, struct vnode *vp, struct vnstat *vn)
{
struct denode denode;
static struct dosmount *mounts;
struct dosmount *mnt;
u_long dirsperblk;
int fileid;
if (!kvm_read_all(kd, (unsigned long)VTODE(vp), &denode,
sizeof(denode))) {
warnx("can't read denode at %p", (void *)VTODE(vp));
return (1);
}
/*
* Find msdosfsmount structure for the vnode's filesystem. Needed
* for some filesystem parameters
*/
for (mnt = mounts; mnt; mnt = mnt->next)
if (mnt->kptr == denode.de_pmp)
break;
if (!mnt) {
if ((mnt = malloc(sizeof(struct dosmount))) == NULL) {
warn("malloc()");
return (1);
}
if (!kvm_read_all(kd, (unsigned long)denode.de_pmp,
&mnt->data, sizeof(mnt->data))) {
free(mnt);
warnx("can't read mount info at %p",
(void *)denode.de_pmp);
return (1);
}
mnt->next = mounts;
mounts = mnt;
mnt->kptr = denode.de_pmp;
}
vn->vn_fsid = dev2udev(kd, mnt->data.pm_dev);
vn->vn_mode = 0555;
vn->vn_mode |= denode.de_Attributes & ATTR_READONLY ? 0 : 0222;
vn->vn_mode &= mnt->data.pm_mask;
/* Distinguish directories and files. No "special" files in FAT. */
vn->vn_mode |= denode.de_Attributes & ATTR_DIRECTORY ? S_IFDIR : S_IFREG;
vn->vn_size = denode.de_FileSize;
/*
* XXX -
* Culled from msdosfs_vnops.c. There appears to be a problem
* here, in that a directory has the same inode number as the first
* file in the directory. stat(2) suffers from this problem also, so
* I won't try to fix it here.
*
* 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.
*/
dirsperblk = mnt->data.pm_BytesPerSec / sizeof(struct direntry);
if (denode.de_Attributes & ATTR_DIRECTORY) {
fileid = cntobn(&mnt->data, denode.de_StartCluster)
* dirsperblk;
if (denode.de_StartCluster == MSDOSFSROOT)
fileid = 1;
} else {
fileid = cntobn(&mnt->data, denode.de_dirclust) * dirsperblk;
if (denode.de_dirclust == MSDOSFSROOT)
fileid = roottobn(&mnt->data, 0) * dirsperblk;
fileid += denode.de_diroffset / sizeof(struct direntry);
}
vn->vn_fileid = fileid;
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;
}
}
int
msdosfs_getattr(void *v)
{
struct vop_getattr_args *ap = v;
struct denode *dep = VTODE(ap->a_vp);
struct msdosfsmount *pmp = dep->de_pmp;
struct vattr *vap = ap->a_vap;
struct timespec ts;
uint32_t fileid;
getnanotime(&ts);
DETIMES(dep, &ts, &ts, &ts);
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.
*
* We now use the starting cluster number as the fileid/fileno.
* This works for both files and directories (including the root
* directory, on FAT32). Even on FAT32, this will at most be a
* 28-bit number, as the high 4 bits of FAT32 cluster numbers
* are reserved.
*
* However, we do need to do something for 0-length files, which
* will not have a starting cluster number.
*
* These files cannot be directories, since (except for /, which
* is special-cased anyway) directories contain entries for . and
* .., so must have non-zero length.
*
* In this case, we just create a non-cryptographic hash of the
* original fileid calculation, and set the top bit.
*
* This algorithm has the benefit that all directories, and all
* non-zero-length files, will have fileids that are persistent
* across mounts and reboots, and that cannot collide (as long
* as the filesystem is not corrupt). Zero-length files will
* have fileids that are persistent, but that may collide. We
* will just have to live with that.
*/
fileid = dep->de_StartCluster;
if (dep->de_Attributes & ATTR_DIRECTORY) {
/* Special-case root */
if (dep->de_StartCluster == MSDOSFSROOT)
fileid = FAT32(pmp) ? pmp->pm_rootdirblk : 1;
} else {
if (dep->de_FileSize == 0) {
uint32_t dirsperblk;
uint64_t fileid64;
dirsperblk = pmp->pm_BytesPerSec /
sizeof(struct direntry);
fileid64 = (dep->de_dirclust == MSDOSFSROOT) ?
roottobn(pmp, 0) : cntobn(pmp, dep->de_dirclust);
fileid64 *= dirsperblk;
fileid64 += dep->de_diroffset / sizeof(struct direntry);
fileid = fileidhash(fileid64);
}
}
vap->va_fileid = fileid;
vap->va_mode = (S_IXUSR|S_IXGRP|S_IXOTH) | (S_IRUSR|S_IRGRP|S_IROTH) |
((dep->de_Attributes & ATTR_READONLY) ? 0 : (S_IWUSR|S_IWGRP|S_IWOTH));
vap->va_mode &= dep->de_pmp->pm_mask;
if (dep->de_Attributes & ATTR_DIRECTORY) {
vap->va_mode |= S_IFDIR;
if (pmp->pm_flags & MSDOSFSMNT_ALLOWDIRX) {
vap->va_mode |= (vap->va_mode & S_IRUSR) ? S_IXUSR : 0;
vap->va_mode |= (vap->va_mode & S_IRGRP) ? S_IXGRP : 0;
vap->va_mode |= (vap->va_mode & S_IROTH) ? S_IXOTH : 0;
}
}
vap->va_nlink = 1;
vap->va_gid = dep->de_pmp->pm_gid;
vap->va_uid = dep->de_pmp->pm_uid;
vap->va_rdev = 0;
vap->va_size = dep->de_FileSize;
dos2unixtime(dep->de_MDate, dep->de_MTime, 0, &vap->va_mtime);
if (dep->de_pmp->pm_flags & MSDOSFSMNT_LONGNAME) {
dos2unixtime(dep->de_ADate, 0, 0, &vap->va_atime);
dos2unixtime(dep->de_CDate, dep->de_CTime, dep->de_CTimeHundredth, &vap->va_ctime);
} else {
vap->va_atime = vap->va_mtime;
vap->va_ctime = vap->va_mtime;
}
vap->va_flags = 0;
if ((dep->de_Attributes & ATTR_ARCHIVE) == 0)
vap->va_flags |= SF_ARCHIVED;
vap->va_gen = 0;
vap->va_blocksize = dep->de_pmp->pm_bpcluster;
vap->va_bytes = (dep->de_FileSize + dep->de_pmp->pm_crbomask) &
~(dep->de_pmp->pm_crbomask);
vap->va_type = ap->a_vp->v_type;
return (0);
}
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);
}
int
msdosfs_mkdir(void *v)
{
struct vop_mkdir_args *ap = v;
struct componentname *cnp = ap->a_cnp;
struct denode ndirent;
struct denode *dep;
struct denode *pdep = VTODE(ap->a_dvp);
int error;
daddr64_t bn;
uint32_t newcluster, pcl;
struct direntry *denp;
struct msdosfsmount *pmp = pdep->de_pmp;
struct buf *bp;
struct timespec ts;
/*
* If this is the root directory and there is no space left we
* can't do anything. This is because the root directory can not
* change size.
*/
if (pdep->de_StartCluster == MSDOSFSROOT
&& pdep->de_fndoffset >= pdep->de_FileSize) {
error = ENOSPC;
goto bad2;
}
/*
* Allocate a cluster to hold the about to be created directory.
*/
error = clusteralloc(pmp, 0, 1, CLUST_EOFE, &newcluster, NULL);
if (error)
goto bad2;
bzero(&ndirent, sizeof(ndirent));
ndirent.de_pmp = pmp;
ndirent.de_flag = DE_ACCESS | DE_CREATE | DE_UPDATE;
getnanotime(&ts);
DETIMES(&ndirent, &ts, &ts, &ts);
/*
* Now fill the cluster with the "." and ".." entries. And write
* the cluster to disk. This way it is there for the parent
* directory to be pointing at if there were a crash.
*/
bn = cntobn(pmp, newcluster);
/* always succeeds */
bp = getblk(pmp->pm_devvp, bn, pmp->pm_bpcluster, 0, 0);
bzero(bp->b_data, pmp->pm_bpcluster);
bcopy(&dosdirtemplate, bp->b_data, sizeof dosdirtemplate);
denp = (struct direntry *)bp->b_data;
putushort(denp[0].deStartCluster, newcluster);
putushort(denp[0].deCDate, ndirent.de_CDate);
putushort(denp[0].deCTime, ndirent.de_CTime);
denp[0].deCTimeHundredth = ndirent.de_CTimeHundredth;
putushort(denp[0].deADate, ndirent.de_ADate);
putushort(denp[0].deMDate, ndirent.de_MDate);
putushort(denp[0].deMTime, ndirent.de_MTime);
pcl = pdep->de_StartCluster;
if (FAT32(pmp) && pcl == pmp->pm_rootdirblk)
pcl = 0;
putushort(denp[1].deStartCluster, pcl);
putushort(denp[1].deCDate, ndirent.de_CDate);
putushort(denp[1].deCTime, ndirent.de_CTime);
denp[1].deCTimeHundredth = ndirent.de_CTimeHundredth;
putushort(denp[1].deADate, ndirent.de_ADate);
putushort(denp[1].deMDate, ndirent.de_MDate);
putushort(denp[1].deMTime, ndirent.de_MTime);
if (FAT32(pmp)) {
putushort(denp[0].deHighClust, newcluster >> 16);
putushort(denp[1].deHighClust, pdep->de_StartCluster >> 16);
}
if ((error = bwrite(bp)) != 0)
goto bad;
/*
* Now build up a directory entry pointing to the newly allocated
* cluster. This will be written to an empty slot in the parent
* directory.
*/
#ifdef DIAGNOSTIC
if ((cnp->cn_flags & HASBUF) == 0)
panic("msdosfs_mkdir: no name");
#endif
if ((error = uniqdosname(pdep, cnp, ndirent.de_Name)) != 0)
goto bad;
ndirent.de_Attributes = ATTR_DIRECTORY;
ndirent.de_StartCluster = newcluster;
ndirent.de_FileSize = 0;
ndirent.de_dev = pdep->de_dev;
ndirent.de_devvp = pdep->de_devvp;
if ((error = createde(&ndirent, pdep, &dep, cnp)) != 0)
goto bad;
if ((cnp->cn_flags & SAVESTART) == 0)
pool_put(&namei_pool, cnp->cn_pnbuf);
vput(ap->a_dvp);
*ap->a_vpp = DETOV(dep);
return (0);
bad:
clusterfree(pmp, newcluster, NULL);
bad2:
pool_put(&namei_pool, cnp->cn_pnbuf);
vput(ap->a_dvp);
return (error);
}
