/*
* Find empty directory entry and put new entry on it.
* This search is done only in directory of specified cluster.
* @dvp: vnode for directory.
* @np: pointer to fat node
*/
int
fatfs_add_node(vnode_t dvp, struct fatfs_node *np)
{
struct fatfsmount *fmp;
u_long cl, sec, sec_start;
int err;
u_long i, next;
fmp = (struct fatfsmount *)dvp->v_mount->m_data;
cl = dvp->v_blkno;
DPRINTF(("fatfs_add_node: cl=%d\n", cl));
if (cl == CL_ROOT && !(FAT32(fmp))) {
/* Add entry in root directory */
sec_start = fmp->root_start;
for (sec = sec_start; sec < fmp->data_start; sec++) {
err = fat_add_dirent(fmp, sec, np);
if (err != ENOENT)
return err;
}
} else {
/* Search entry in sub directory */
if(cl == CL_ROOT) /* CL_ROOT of FAT32 */
cl = fmp->root_start;
while (!IS_EOFCL(fmp, cl)) {
sec = cl_to_sec(fmp, cl);
for (i = 0; i < fmp->sec_per_cl; i++) {
err = fat_add_dirent(fmp, sec, np);
if (err != ENOENT)
return err;
sec++;
}
err = fat_next_cluster(fmp, cl, &next);
if (err)
return err;
cl = next;
}
/* No entry found, add one more free cluster for directory */
DPRINTF(("fatfs_add_node: expand dir\n"));
err = fat_expand_dir(fmp, cl, &next);
if (err)
return err;
/* Initialize free cluster. */
memset(fmp->dir_buf, 0, SEC_SIZE);
sec = cl_to_sec(fmp, next);
for (i = 0; i < fmp->sec_per_cl; i++) {
err = fat_write_dirent(fmp, sec);
if (err)
return err;
sec++;
}
/* Try again */
sec = cl_to_sec(fmp, next);
err = fat_add_dirent(fmp, sec, np);
return err;
}
return ENOENT;
}
static int
update_mp(struct mount *mp, struct msdosfs_args *argp)
{
struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
int error;
char cs_local[ICONV_CSNMAXLEN];
char cs_dos[ICONV_CSNMAXLEN];
pmp->pm_gid = argp->gid;
pmp->pm_uid = argp->uid;
pmp->pm_mask = argp->mask & ALLPERMS;
pmp->pm_flags |= argp->flags & MSDOSFSMNT_MNTOPT;
if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdos_iconv) {
bcopy(argp->cs_local, cs_local, sizeof(cs_local));
bcopy(argp->cs_dos, cs_dos, sizeof(cs_dos));
kprintf("local: %s dos: %s\n",argp->cs_local, argp->cs_dos);
error = msdos_iconv->open(cs_local, ENCODING_UNICODE, &pmp->pm_w2u);
if(error)
return error;
error = msdos_iconv->open(ENCODING_UNICODE, cs_local, &pmp->pm_u2w);
if(error)
return error;
error = msdos_iconv->open(cs_dos, cs_local, &pmp->pm_u2d);
if(error)
return error;
error = msdos_iconv->open(cs_local, cs_dos, &pmp->pm_d2u);
if(error)
return error;
}
if (pmp->pm_flags & MSDOSFSMNT_NOWIN95)
pmp->pm_flags |= MSDOSFSMNT_SHORTNAME;
else if (!(pmp->pm_flags &
(MSDOSFSMNT_SHORTNAME | MSDOSFSMNT_LONGNAME))) {
struct vnode *rootvp;
/*
* Try to divine whether to support Win'95 long filenames
*/
if (FAT32(pmp))
pmp->pm_flags |= MSDOSFSMNT_LONGNAME;
else {
if ((error = msdosfs_root(mp, &rootvp)) != 0)
return error;
pmp->pm_flags |= findwin95(VTODE(rootvp))
? MSDOSFSMNT_LONGNAME
: MSDOSFSMNT_SHORTNAME;
vput(rootvp);
}
}
return 0;
}
/*
* Find directory entry for specified name in directory.
* The fat vnode data is filled if success.
*
* @dvp: vnode for directory.
* @name: file name
* @np: pointer to fat node
*/
int
fatfs_lookup_node(vnode_t dvp, char *name, struct fatfs_node *np)
{
struct fatfsmount *fmp;
char fat_name[12];
u_long i, cl, sec, sec_start;
int err;
if (name == NULL)
return ENOENT;
DPRINTF(("fat_lookup_denode: cl=%d name=%s\n", dvp->v_blkno, name));
fat_convert_name(name, fat_name);
*(fat_name + 11) = '\0';
fmp = (struct fatfsmount *)dvp->v_mount->m_data;
cl = dvp->v_blkno;
if (cl == CL_ROOT && !(FAT32(fmp))) {
/* Search entry in root directory */
sec_start = fmp->root_start;
for (sec = sec_start; sec < fmp->data_start; sec++) {
err = fat_lookup_dirent(fmp, sec, fat_name, np);
if (err != EAGAIN)
return err;
}
} else {
/* Search entry in sub directory */
if(cl == CL_ROOT) /* CL_ROOT of FAT32 */
cl = fmp->root_start;
while (!IS_EOFCL(fmp, cl)) {
sec = cl_to_sec(fmp, cl);
for (i = 0; i < fmp->sec_per_cl; i++) {
err = fat_lookup_dirent(fmp, sec, fat_name,
np);
if (err != EAGAIN)
return err;
sec++;
}
err = fat_next_cluster(fmp, cl, &cl);
if (err)
return err;
}
}
return ENOENT;
}
/*
* Extend the file described by dep to length specified by length.
*/
int
deextend(struct denode *dep, u_long length, struct kauth_cred *cred)
{
struct msdosfsmount *pmp = dep->de_pmp;
u_long count;
int error;
/*
* The root of a DOS filesystem cannot be extended.
*/
if (dep->de_vnode != NULL && !FAT32(pmp))
return EINVAL;
/*
* Directories cannot be extended.
*/
if (dep->de_Attributes & ATTR_DIRECTORY)
return EISDIR;
if (length <= dep->de_FileSize)
return E2BIG;
/*
* Compute the number of clusters to allocate.
*/
count = de_clcount(pmp, length) - de_clcount(pmp, dep->de_FileSize);
if (count > 0) {
if (count > pmp->pm_freeclustercount)
return (ENOSPC);
error = extendfile(dep, count, NULL, NULL, DE_CLEAR);
if (error) {
/* truncate the added clusters away again */
(void) detrunc(dep, dep->de_FileSize, 0, cred);
return (error);
}
}
/*
* Zero extend file range; ubc_zerorange() uses ubc_alloc() and a
* memset(); we set the write size so ubc won't read in file data that
* is zero'd later.
*/
dep->de_FileSize = length;
dep->de_flag |= DE_UPDATE|DE_MODIFIED;
return 0;
}
static int
update_mp(struct mount *mp, struct msdosfs_args *argp)
{
struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
int error;
pmp->pm_gid = argp->gid;
pmp->pm_uid = argp->uid;
pmp->pm_mask = argp->mask & ALLPERMS;
pmp->pm_dirmask = argp->dirmask & ALLPERMS;
pmp->pm_gmtoff = argp->gmtoff;
pmp->pm_flags |= argp->flags & MSDOSFSMNT_MNTOPT;
/*
* GEMDOS knows nothing about win95 long filenames
*/
if (pmp->pm_flags & MSDOSFSMNT_GEMDOSFS)
pmp->pm_flags |= MSDOSFSMNT_NOWIN95;
if (pmp->pm_flags & MSDOSFSMNT_NOWIN95)
pmp->pm_flags |= MSDOSFSMNT_SHORTNAME;
else if (!(pmp->pm_flags &
(MSDOSFSMNT_SHORTNAME | MSDOSFSMNT_LONGNAME))) {
struct vnode *rtvp;
/*
* Try to divine whether to support Win'95 long filenames
*/
if (FAT32(pmp))
pmp->pm_flags |= MSDOSFSMNT_LONGNAME;
else {
if ((error = msdosfs_root(mp, &rtvp)) != 0)
return error;
pmp->pm_flags |= findwin95(VTODE(rtvp))
? MSDOSFSMNT_LONGNAME
: MSDOSFSMNT_SHORTNAME;
vput(rtvp);
}
}
mp->mnt_stat.f_namemax = MSDOSFS_NAMEMAX(pmp);
return 0;
}
/*
* Extend the file described by dep to length specified by length.
*/
int
deextend(struct denode *dep, uint32_t length, struct ucred *cred)
{
struct msdosfsmount *pmp = dep->de_pmp;
uint32_t count;
int error;
/*
* The root of a DOS filesystem cannot be extended.
*/
if ((DETOV(dep)->v_flag & VROOT) && !FAT32(pmp))
return (EINVAL);
/*
* Directories cannot be extended.
*/
if (dep->de_Attributes & ATTR_DIRECTORY)
return (EISDIR);
if (length <= dep->de_FileSize)
panic("deextend: file too large");
/*
* Compute the number of clusters to allocate.
*/
count = de_clcount(pmp, length) - de_clcount(pmp, dep->de_FileSize);
if (count > 0) {
if (count > pmp->pm_freeclustercount)
return (ENOSPC);
error = extendfile(dep, count, NULL, NULL, DE_CLEAR);
if (error) {
/* truncate the added clusters away again */
(void) detrunc(dep, dep->de_FileSize, 0, cred, NULL);
return (error);
}
}
dep->de_FileSize = length;
dep->de_flag |= DE_UPDATE|DE_MODIFIED;
return (deupdat(dep, 1));
}
/*
* Get directory entry for specified index.
*
* @dvp: vnode for directory.
* @index: index of the entry
* @np: pointer to fat node
*/
int
fatfs_get_node(vnode_t dvp, int index, struct fatfs_node *np)
{
struct fatfsmount *fmp;
u_long i, cl, sec, sec_start;
int cur_index, err;
fmp = (struct fatfsmount *)dvp->v_mount->m_data;
cl = dvp->v_blkno;
cur_index = 0;
DPRINTF(("fatfs_get_node: index=%d\n", index));
if (cl == CL_ROOT && !(FAT32(fmp))) {
/* Get entry from the root directory */
sec_start = fmp->root_start;
for (sec = sec_start; sec < fmp->data_start; sec++) {
err = fat_get_dirent(fmp, sec, index, &cur_index, np);
if (err != EAGAIN)
return err;
}
} else {
if(cl == CL_ROOT) /* CL_ROOT of FAT32 */
cl = fmp->root_start;
/* Get entry from the sub directory */
while (!IS_EOFCL(fmp, cl)) {
sec = cl_to_sec(fmp, cl);
for (i = 0; i < fmp->sec_per_cl; i++) {
err = fat_get_dirent(fmp, sec, index,
&cur_index, np);
if (err != EAGAIN)
return err;
sec++;
}
err = fat_next_cluster(fmp, cl, &cl);
if (err)
return err;
}
}
return ENOENT;
}
/*
* 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;
}
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);
}
static int
mountmsdosfs(struct vnode *devvp, struct mount *mp)
{
struct msdosfsmount *pmp;
struct buf *bp;
struct cdev *dev;
union bootsector *bsp;
struct byte_bpb33 *b33;
struct byte_bpb50 *b50;
struct byte_bpb710 *b710;
u_int8_t SecPerClust;
u_long clusters;
int ronly, error;
struct g_consumer *cp;
struct bufobj *bo;
bp = NULL; /* This and pmp both used in error_exit. */
pmp = NULL;
ronly = (mp->mnt_flag & MNT_RDONLY) != 0;
dev = devvp->v_rdev;
dev_ref(dev);
DROP_GIANT();
g_topology_lock();
error = g_vfs_open(devvp, &cp, "msdosfs", ronly ? 0 : 1);
g_topology_unlock();
PICKUP_GIANT();
VOP_UNLOCK(devvp, 0);
if (error)
goto error_exit;
bo = &devvp->v_bufobj;
/*
* Read the boot sector of the filesystem, and then check the
* boot signature. If not a dos boot sector then error out.
*
* NOTE: 8192 is a magic size that works for ffs.
*/
error = bread(devvp, 0, 8192, NOCRED, &bp);
if (error)
goto error_exit;
bp->b_flags |= B_AGE;
bsp = (union bootsector *)bp->b_data;
b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB;
b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB;
b710 = (struct byte_bpb710 *)bsp->bs710.bsBPB;
#ifndef MSDOSFS_NOCHECKSIG
if (bsp->bs50.bsBootSectSig0 != BOOTSIG0
|| bsp->bs50.bsBootSectSig1 != BOOTSIG1) {
error = EINVAL;
goto error_exit;
}
#endif
pmp = malloc(sizeof *pmp, M_MSDOSFSMNT, M_WAITOK | M_ZERO);
pmp->pm_mountp = mp;
pmp->pm_cp = cp;
pmp->pm_bo = bo;
lockinit(&pmp->pm_fatlock, 0, msdosfs_lock_msg, 0, 0);
/*
* Initialize ownerships and permissions, since nothing else will
* initialize them iff we are mounting root.
*/
pmp->pm_uid = UID_ROOT;
pmp->pm_gid = GID_WHEEL;
pmp->pm_mask = pmp->pm_dirmask = S_IXUSR | S_IXGRP | S_IXOTH |
S_IRUSR | S_IRGRP | S_IROTH | S_IWUSR;
/*
* Experimental support for large MS-DOS filesystems.
* WARNING: This uses at least 32 bytes of kernel memory (which is not
* reclaimed until the FS is unmounted) for each file on disk to map
* between the 32-bit inode numbers used by VFS and the 64-bit
* pseudo-inode numbers used internally by msdosfs. This is only
* safe to use in certain controlled situations (e.g. read-only FS
* with less than 1 million files).
* Since the mappings do not persist across unmounts (or reboots), these
* filesystems are not suitable for exporting through NFS, or any other
* application that requires fixed inode numbers.
*/
vfs_flagopt(mp->mnt_optnew, "large", &pmp->pm_flags, MSDOSFS_LARGEFS);
/*
* Compute several useful quantities from the bpb in the
* bootsector. Copy in the dos 5 variant of the bpb then fix up
* the fields that are different between dos 5 and dos 3.3.
*/
SecPerClust = b50->bpbSecPerClust;
pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec);
if (pmp->pm_BytesPerSec < DEV_BSIZE) {
error = EINVAL;
goto error_exit;
}
pmp->pm_ResSectors = getushort(b50->bpbResSectors);
pmp->pm_FATs = b50->bpbFATs;
pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts);
pmp->pm_Sectors = getushort(b50->bpbSectors);
pmp->pm_FATsecs = getushort(b50->bpbFATsecs);
pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack);
pmp->pm_Heads = getushort(b50->bpbHeads);
pmp->pm_Media = b50->bpbMedia;
/* calculate the ratio of sector size to DEV_BSIZE */
pmp->pm_BlkPerSec = pmp->pm_BytesPerSec / DEV_BSIZE;
/*
* We don't check pm_Heads nor pm_SecPerTrack, because
* these may not be set for EFI file systems. We don't
* use these anyway, so we're unaffected if they are
* invalid.
*/
if (!pmp->pm_BytesPerSec || !SecPerClust) {
error = EINVAL;
goto error_exit;
}
if (pmp->pm_Sectors == 0) {
pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs);
pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors);
} else {
pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs);
pmp->pm_HugeSectors = pmp->pm_Sectors;
}
if (!(pmp->pm_flags & MSDOSFS_LARGEFS)) {
if (pmp->pm_HugeSectors > 0xffffffff /
(pmp->pm_BytesPerSec / sizeof(struct direntry)) + 1) {
/*
* We cannot deal currently with this size of disk
* due to fileid limitations (see msdosfs_getattr and
* msdosfs_readdir)
*/
error = EINVAL;
vfs_mount_error(mp,
"Disk too big, try '-o large' mount option");
goto error_exit;
}
}
if (pmp->pm_RootDirEnts == 0) {
if (pmp->pm_FATsecs
|| getushort(b710->bpbFSVers)) {
error = EINVAL;
#ifdef MSDOSFS_DEBUG
printf("mountmsdosfs(): bad FAT32 filesystem\n");
#endif
goto error_exit;
}
pmp->pm_fatmask = FAT32_MASK;
pmp->pm_fatmult = 4;
pmp->pm_fatdiv = 1;
pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs);
if (getushort(b710->bpbExtFlags) & FATMIRROR)
pmp->pm_curfat = getushort(b710->bpbExtFlags) & FATNUM;
else
pmp->pm_flags |= MSDOSFS_FATMIRROR;
} else
pmp->pm_flags |= MSDOSFS_FATMIRROR;
/*
* Check a few values (could do some more):
* - logical sector size: power of 2, >= block size
* - sectors per cluster: power of 2, >= 1
* - number of sectors: >= 1, <= size of partition
* - number of FAT sectors: >= 1
*/
if ( (SecPerClust == 0)
|| (SecPerClust & (SecPerClust - 1))
|| (pmp->pm_BytesPerSec < DEV_BSIZE)
|| (pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1))
|| (pmp->pm_HugeSectors == 0)
|| (pmp->pm_FATsecs == 0)
|| (SecPerClust * pmp->pm_BlkPerSec > MAXBSIZE / DEV_BSIZE)
) {
error = EINVAL;
goto error_exit;
}
pmp->pm_HugeSectors *= pmp->pm_BlkPerSec;
pmp->pm_HiddenSects *= pmp->pm_BlkPerSec; /* XXX not used? */
pmp->pm_FATsecs *= pmp->pm_BlkPerSec;
SecPerClust *= pmp->pm_BlkPerSec;
pmp->pm_fatblk = pmp->pm_ResSectors * pmp->pm_BlkPerSec;
if (FAT32(pmp)) {
pmp->pm_rootdirblk = getulong(b710->bpbRootClust);
pmp->pm_firstcluster = pmp->pm_fatblk
+ (pmp->pm_FATs * pmp->pm_FATsecs);
pmp->pm_fsinfo = getushort(b710->bpbFSInfo) * pmp->pm_BlkPerSec;
} else {
pmp->pm_rootdirblk = pmp->pm_fatblk +
(pmp->pm_FATs * pmp->pm_FATsecs);
pmp->pm_rootdirsize = howmany(pmp->pm_RootDirEnts *
sizeof(struct direntry), DEV_BSIZE); /* in blocks */
pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize;
}
pmp->pm_maxcluster = (pmp->pm_HugeSectors - pmp->pm_firstcluster) /
SecPerClust + 1;
pmp->pm_fatsize = pmp->pm_FATsecs * DEV_BSIZE; /* XXX not used? */
if (pmp->pm_fatmask == 0) {
if (pmp->pm_maxcluster
<= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) {
/*
* This will usually be a floppy disk. This size makes
* sure that one fat entry will not be split across
* multiple blocks.
*/
pmp->pm_fatmask = FAT12_MASK;
pmp->pm_fatmult = 3;
pmp->pm_fatdiv = 2;
} else {
pmp->pm_fatmask = FAT16_MASK;
pmp->pm_fatmult = 2;
pmp->pm_fatdiv = 1;
}
}
clusters = (pmp->pm_fatsize / pmp->pm_fatmult) * pmp->pm_fatdiv;
if (pmp->pm_maxcluster >= clusters) {
#ifdef MSDOSFS_DEBUG
printf("Warning: number of clusters (%ld) exceeds FAT "
"capacity (%ld)\n", pmp->pm_maxcluster + 1, clusters);
#endif
pmp->pm_maxcluster = clusters - 1;
}
if (FAT12(pmp))
pmp->pm_fatblocksize = 3 * 512;
else
pmp->pm_fatblocksize = PAGE_SIZE;
pmp->pm_fatblocksize = roundup(pmp->pm_fatblocksize,
pmp->pm_BytesPerSec);
pmp->pm_fatblocksec = pmp->pm_fatblocksize / DEV_BSIZE;
pmp->pm_bnshift = ffs(DEV_BSIZE) - 1;
/*
* Compute mask and shift value for isolating cluster relative byte
* offsets and cluster numbers from a file offset.
*/
pmp->pm_bpcluster = SecPerClust * DEV_BSIZE;
pmp->pm_crbomask = pmp->pm_bpcluster - 1;
pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1;
/*
* Check for valid cluster size
* must be a power of 2
*/
if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) {
error = EINVAL;
goto error_exit;
}
/*
* Release the bootsector buffer.
*/
brelse(bp);
bp = NULL;
/*
* Check the fsinfo sector if we have one. Silently fix up our
* in-core copy of fp->fsinxtfree if it is unknown (0xffffffff)
* or too large. Ignore fp->fsinfree for now, since we need to
* read the entire FAT anyway to fill the inuse map.
*/
if (pmp->pm_fsinfo) {
struct fsinfo *fp;
if ((error = bread(devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec,
NOCRED, &bp)) != 0)
goto error_exit;
fp = (struct fsinfo *)bp->b_data;
if (!bcmp(fp->fsisig1, "RRaA", 4)
&& !bcmp(fp->fsisig2, "rrAa", 4)
&& !bcmp(fp->fsisig3, "\0\0\125\252", 4)) {
pmp->pm_nxtfree = getulong(fp->fsinxtfree);
if (pmp->pm_nxtfree > pmp->pm_maxcluster)
pmp->pm_nxtfree = CLUST_FIRST;
} else
pmp->pm_fsinfo = 0;
brelse(bp);
bp = NULL;
}
/*
* Finish initializing pmp->pm_nxtfree (just in case the first few
* sectors aren't properly reserved in the FAT). This completes
* the fixup for fp->fsinxtfree, and fixes up the zero-initialized
* value if there is no fsinfo. We will use pmp->pm_nxtfree
* internally even if there is no fsinfo.
*/
if (pmp->pm_nxtfree < CLUST_FIRST)
pmp->pm_nxtfree = CLUST_FIRST;
/*
* Allocate memory for the bitmap of allocated clusters, and then
* fill it in.
*/
pmp->pm_inusemap = malloc(howmany(pmp->pm_maxcluster + 1, N_INUSEBITS)
* sizeof(*pmp->pm_inusemap),
M_MSDOSFSFAT, M_WAITOK);
/*
* fillinusemap() needs pm_devvp.
*/
pmp->pm_devvp = devvp;
pmp->pm_dev = dev;
/*
* Have the inuse map filled in.
*/
MSDOSFS_LOCK_MP(pmp);
error = fillinusemap(pmp);
MSDOSFS_UNLOCK_MP(pmp);
if (error != 0)
goto error_exit;
/*
* If they want fat updates to be synchronous then let them suffer
* the performance degradation in exchange for the on disk copy of
* the fat being correct just about all the time. I suppose this
* would be a good thing to turn on if the kernel is still flakey.
*/
if (mp->mnt_flag & MNT_SYNCHRONOUS)
pmp->pm_flags |= MSDOSFSMNT_WAITONFAT;
/*
* Finish up.
*/
if (ronly)
pmp->pm_flags |= MSDOSFSMNT_RONLY;
else {
if ((error = markvoldirty(pmp, 1)) != 0) {
(void)markvoldirty(pmp, 0);
goto error_exit;
}
pmp->pm_fmod = 1;
}
mp->mnt_data = pmp;
mp->mnt_stat.f_fsid.val[0] = dev2udev(dev);
mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum;
MNT_ILOCK(mp);
mp->mnt_flag |= MNT_LOCAL;
mp->mnt_kern_flag |= MNTK_USES_BCACHE;
MNT_IUNLOCK(mp);
if (pmp->pm_flags & MSDOSFS_LARGEFS)
msdosfs_fileno_init(mp);
return 0;
error_exit:
if (bp)
brelse(bp);
if (cp != NULL) {
DROP_GIANT();
g_topology_lock();
g_vfs_close(cp);
g_topology_unlock();
PICKUP_GIANT();
}
if (pmp) {
lockdestroy(&pmp->pm_fatlock);
if (pmp->pm_inusemap)
free(pmp->pm_inusemap, M_MSDOSFSFAT);
free(pmp, M_MSDOSFSMNT);
mp->mnt_data = NULL;
}
dev_rel(dev);
return (error);
}
static int
update_mp(struct mount *mp, struct thread *td)
{
struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
void *dos, *win, *local;
int error, v;
if (!vfs_getopt(mp->mnt_optnew, "kiconv", NULL, NULL)) {
if (msdosfs_iconv != NULL) {
error = vfs_getopt(mp->mnt_optnew,
"cs_win", &win, NULL);
if (!error)
error = vfs_getopt(mp->mnt_optnew,
"cs_local", &local, NULL);
if (!error)
error = vfs_getopt(mp->mnt_optnew,
"cs_dos", &dos, NULL);
if (!error) {
msdosfs_iconv->open(win, local, &pmp->pm_u2w);
msdosfs_iconv->open(local, win, &pmp->pm_w2u);
msdosfs_iconv->open(dos, local, &pmp->pm_u2d);
msdosfs_iconv->open(local, dos, &pmp->pm_d2u);
}
if (error != 0)
return (error);
} else {
pmp->pm_w2u = NULL;
pmp->pm_u2w = NULL;
pmp->pm_d2u = NULL;
pmp->pm_u2d = NULL;
}
}
if (vfs_scanopt(mp->mnt_optnew, "gid", "%d", &v) == 1)
pmp->pm_gid = v;
if (vfs_scanopt(mp->mnt_optnew, "uid", "%d", &v) == 1)
pmp->pm_uid = v;
if (vfs_scanopt(mp->mnt_optnew, "mask", "%d", &v) == 1)
pmp->pm_mask = v & ALLPERMS;
if (vfs_scanopt(mp->mnt_optnew, "dirmask", "%d", &v) == 1)
pmp->pm_dirmask = v & ALLPERMS;
vfs_flagopt(mp->mnt_optnew, "shortname",
&pmp->pm_flags, MSDOSFSMNT_SHORTNAME);
vfs_flagopt(mp->mnt_optnew, "shortnames",
&pmp->pm_flags, MSDOSFSMNT_SHORTNAME);
vfs_flagopt(mp->mnt_optnew, "longname",
&pmp->pm_flags, MSDOSFSMNT_LONGNAME);
vfs_flagopt(mp->mnt_optnew, "longnames",
&pmp->pm_flags, MSDOSFSMNT_LONGNAME);
vfs_flagopt(mp->mnt_optnew, "kiconv",
&pmp->pm_flags, MSDOSFSMNT_KICONV);
if (vfs_getopt(mp->mnt_optnew, "nowin95", NULL, NULL) == 0)
pmp->pm_flags |= MSDOSFSMNT_NOWIN95;
else
pmp->pm_flags &= ~MSDOSFSMNT_NOWIN95;
if (pmp->pm_flags & MSDOSFSMNT_NOWIN95)
pmp->pm_flags |= MSDOSFSMNT_SHORTNAME;
else if (!(pmp->pm_flags &
(MSDOSFSMNT_SHORTNAME | MSDOSFSMNT_LONGNAME))) {
struct vnode *rootvp;
/*
* Try to divine whether to support Win'95 long filenames
*/
if (FAT32(pmp))
pmp->pm_flags |= MSDOSFSMNT_LONGNAME;
else {
if ((error =
msdosfs_root(mp, LK_EXCLUSIVE, &rootvp)) != 0)
return error;
pmp->pm_flags |= findwin95(VTODE(rootvp)) ?
MSDOSFSMNT_LONGNAME : MSDOSFSMNT_SHORTNAME;
vput(rootvp);
}
}
return 0;
}
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 {
/*
* When we search a directory the blocks containing directory entries are
* read and examined. The directory entries contain information that would
* normally be in the inode of a unix filesystem. This means that some of
* a directory's contents may also be in memory resident denodes (sort of
* an inode). This can cause problems if we are searching while some other
* process is modifying a directory. To prevent one process from accessing
* incompletely modified directory information we depend upon being the
* sole owner of a directory block. bread/brelse provide this service.
* This being the case, when a process modifies a directory it must first
* acquire the disk block that contains the directory entry to be modified.
* Then update the disk block and the denode, and then write the disk block
* out to disk. This way disk blocks containing directory entries and in
* memory denode's will be in synch.
*
* msdosfs_lookup(struct vnode *a_dvp, struct vnode **a_vpp,
* struct componentname *a_cnp)
*/
int
msdosfs_lookup(struct vop_old_lookup_args *ap)
{
struct mbnambuf nb;
struct vnode *vdp = ap->a_dvp;
struct vnode **vpp = ap->a_vpp;
struct componentname *cnp = ap->a_cnp;
daddr_t bn;
int error;
int lockparent;
int wantparent;
int slotcount;
int slotoffset = 0;
int frcn;
u_long cluster;
int blkoff;
int diroff;
int blsize;
int isadir; /* ~0 if found direntry is a directory */
u_long scn; /* starting cluster number */
struct vnode *pdp;
struct denode *dp;
struct denode *tdp;
struct msdosfsmount *pmp;
struct buf *bp = NULL;
struct direntry *dep = NULL;
u_char dosfilename[12];
int flags = cnp->cn_flags;
int nameiop = cnp->cn_nameiop;
int unlen;
int wincnt = 1;
int chksum = -1;
int olddos = 1;
cnp->cn_flags &= ~CNP_PDIRUNLOCK;
#ifdef MSDOSFS_DEBUG
kprintf("msdosfs_lookup(): looking for %s\n", cnp->cn_nameptr);
#endif
dp = VTODE(vdp);
pmp = dp->de_pmp;
*vpp = NULL;
lockparent = flags & CNP_LOCKPARENT;
wantparent = flags & (CNP_LOCKPARENT | CNP_WANTPARENT);
#ifdef MSDOSFS_DEBUG
kprintf("msdosfs_lookup(): vdp %p, dp %p, Attr %02x\n",
vdp, dp, dp->de_Attributes);
#endif
/*
* If they are going after the . or .. entry in the root directory,
* they won't find it. DOS filesystems don't have them in the root
* directory. So, we fake it. deget() is in on this scam too.
*/
if ((vdp->v_flag & VROOT) && cnp->cn_nameptr[0] == '.' &&
(cnp->cn_namelen == 1 ||
(cnp->cn_namelen == 2 && cnp->cn_nameptr[1] == '.'))) {
isadir = ATTR_DIRECTORY;
scn = MSDOSFSROOT;
#ifdef MSDOSFS_DEBUG
kprintf("msdosfs_lookup(): looking for . or .. in root directory\n");
#endif
cluster = MSDOSFSROOT;
blkoff = MSDOSFSROOT_OFS;
goto foundroot;
}
switch (unix2dosfn((const u_char *)cnp->cn_nameptr, dosfilename,
cnp->cn_namelen, 0, pmp)) {
case 0:
return (EINVAL);
case 1:
break;
case 2:
wincnt = winSlotCnt((const u_char *)cnp->cn_nameptr,
cnp->cn_namelen, pmp) + 1;
break;
case 3:
olddos = 0;
wincnt = winSlotCnt((const u_char *)cnp->cn_nameptr,
cnp->cn_namelen, pmp) + 1;
break;
}
if (pmp->pm_flags & MSDOSFSMNT_SHORTNAME) {
wincnt = 1;
olddos = 1;
}
unlen = winLenFixup(cnp->cn_nameptr, cnp->cn_namelen);
/*
* Suppress search for slots unless creating
* file and at end of pathname, in which case
* we watch for a place to put the new file in
* case it doesn't already exist.
*/
slotcount = wincnt;
if (nameiop == NAMEI_CREATE || nameiop == NAMEI_RENAME)
slotcount = 0;
#ifdef MSDOSFS_DEBUG
kprintf("msdosfs_lookup(): dos version of filename %s, length %ld\n",
dosfilename, cnp->cn_namelen);
#endif
/*
* Search the directory pointed at by vdp for the name pointed at
* by cnp->cn_nameptr.
*/
tdp = NULL;
mbnambuf_init(&nb);
/*
* The outer loop ranges over the clusters that make up the
* directory. Note that the root directory is different from all
* other directories. It has a fixed number of blocks that are not
* part of the pool of allocatable clusters. So, we treat it a
* little differently. The root directory starts at "cluster" 0.
*/
diroff = 0;
for (frcn = 0;; frcn++) {
error = pcbmap(dp, frcn, &bn, &cluster, &blsize);
if (error) {
if (error == E2BIG)
break;
return (error);
}
error = bread(pmp->pm_devvp, de_bntodoff(pmp, bn), blsize, &bp);
if (error) {
brelse(bp);
return (error);
}
for (blkoff = 0; blkoff < blsize;
blkoff += sizeof(struct direntry),
diroff += sizeof(struct direntry)) {
dep = (struct direntry *)(bp->b_data + blkoff);
/*
* If the slot is empty and we are still looking
* for an empty then remember this one. If the
* slot is not empty then check to see if it
* matches what we are looking for. If the slot
* has never been filled with anything, then the
* remainder of the directory has never been used,
* so there is no point in searching it.
*/
if (dep->deName[0] == SLOT_EMPTY ||
dep->deName[0] == SLOT_DELETED) {
/*
* Drop memory of previous long matches
*/
chksum = -1;
mbnambuf_init(&nb);
if (slotcount < wincnt) {
slotcount++;
slotoffset = diroff;
}
if (dep->deName[0] == SLOT_EMPTY) {
brelse(bp);
goto notfound;
}
} else {
/*
* If there wasn't enough space for our winentries,
* forget about the empty space
*/
if (slotcount < wincnt)
slotcount = 0;
/*
* Check for Win95 long filename entry
*/
if (dep->deAttributes == ATTR_WIN95) {
if (pmp->pm_flags & MSDOSFSMNT_SHORTNAME)
continue;
chksum = win2unixfn(&nb,
(struct winentry *)dep, chksum,
pmp);
continue;
}
chksum = winChkName(&nb,
(const u_char *)cnp->cn_nameptr, unlen,
chksum, pmp);
if (chksum == -2) {
chksum = -1;
continue;
}
/*
* Ignore volume labels (anywhere, not just
* the root directory).
*/
if (dep->deAttributes & ATTR_VOLUME) {
chksum = -1;
continue;
}
/*
* Check for a checksum or name match
*/
if (chksum != winChksum(dep->deName)
&& (!olddos || bcmp(dosfilename, dep->deName, 11))) {
chksum = -1;
continue;
}
#ifdef MSDOSFS_DEBUG
kprintf("msdosfs_lookup(): match blkoff %d, diroff %d\n",
blkoff, diroff);
#endif
/*
* Remember where this directory
* entry came from for whoever did
* this lookup.
*/
dp->de_fndoffset = diroff;
dp->de_fndcnt = wincnt - 1;
goto found;
}
} /* for (blkoff = 0; .... */
/*
* Release the buffer holding the directory cluster just
* searched.
*/
brelse(bp);
} /* for (frcn = 0; ; frcn++) */
notfound:
/*
* We hold no disk buffers at this point.
*/
/*
* Fixup the slot description to point to the place where
* we might put the new DOS direntry (putting the Win95
* long name entries before that)
*/
if (!slotcount) {
slotcount = 1;
slotoffset = diroff;
}
if (wincnt > slotcount)
slotoffset += sizeof(struct direntry) * (wincnt - slotcount);
/*
* If we get here we didn't find the entry we were looking for. But
* that's ok if we are creating or renaming and are at the end of
* the pathname and the directory hasn't been removed.
*/
#ifdef MSDOSFS_DEBUG
kprintf("msdosfs_lookup(): op %d, refcnt %ld\n",
nameiop, dp->de_refcnt);
kprintf(" slotcount %d, slotoffset %d\n",
slotcount, slotoffset);
#endif
if ((nameiop == NAMEI_CREATE || nameiop == NAMEI_RENAME) &&
dp->de_refcnt > 0) {
/*
* Access for write is interpreted as allowing
* creation of files in the directory.
*/
error = VOP_EACCESS(vdp, VWRITE, cnp->cn_cred);
if (error)
return (error);
/*
* Return an indication of where the new directory
* entry should be put.
*/
dp->de_fndoffset = slotoffset;
dp->de_fndcnt = wincnt - 1;
/*
* We return with the directory locked, so that
* the parameters we set up above will still be
* valid if we actually decide to do a direnter().
* We return ni_vp == NULL to indicate that the entry
* does not currently exist; we leave a pointer to
* the (locked) directory inode in ndp->ni_dvp.
* The pathname buffer is saved so that the name
* can be obtained later.
*
* NB - if the directory is unlocked, then this
* information cannot be used.
*/
if (!lockparent) {
vn_unlock(vdp);
cnp->cn_flags |= CNP_PDIRUNLOCK;
}
return (EJUSTRETURN);
}
return (ENOENT);
found:
/*
* NOTE: We still have the buffer with matched directory entry at
* this point.
*/
isadir = dep->deAttributes & ATTR_DIRECTORY;
scn = getushort(dep->deStartCluster);
if (FAT32(pmp)) {
scn |= getushort(dep->deHighClust) << 16;
if (scn == pmp->pm_rootdirblk) {
/*
* There should actually be 0 here.
* Just ignore the error.
*/
scn = MSDOSFSROOT;
}
}
if (isadir) {
cluster = scn;
if (cluster == MSDOSFSROOT)
blkoff = MSDOSFSROOT_OFS;
else
blkoff = 0;
} else if (cluster == MSDOSFSROOT)
blkoff = diroff;
/*
* Now release buf to allow deget to read the entry again.
* Reserving it here and giving it to deget could result
* in a deadlock.
*/
brelse(bp);
bp = NULL;
foundroot:
/*
* If we entered at foundroot, then we are looking for the . or ..
* entry of the filesystems root directory. isadir and scn were
* setup before jumping here. And, bp is already null.
*/
if (FAT32(pmp) && scn == MSDOSFSROOT)
scn = pmp->pm_rootdirblk;
/*
* If deleting, and at end of pathname, return
* parameters which can be used to remove file.
* If the wantparent flag isn't set, we return only
* the directory (in ndp->ni_dvp), otherwise we go
* on and lock the inode, being careful with ".".
*/
if (nameiop == NAMEI_DELETE) {
/*
* Don't allow deleting the root.
*/
if (blkoff == MSDOSFSROOT_OFS)
return EROFS; /* really? XXX */
/*
* Write access to directory required to delete files.
*/
error = VOP_EACCESS(vdp, VWRITE, cnp->cn_cred);
if (error)
return (error);
/*
* Return pointer to current entry in dp->i_offset.
* Save directory inode pointer in ndp->ni_dvp for dirremove().
*/
if (dp->de_StartCluster == scn && isadir) { /* "." */
vref(vdp);
*vpp = vdp;
return (0);
}
error = deget(pmp, cluster, blkoff, &tdp);
if (error)
return (error);
*vpp = DETOV(tdp);
if (!lockparent) {
vn_unlock(vdp);
cnp->cn_flags |= CNP_PDIRUNLOCK;
}
return (0);
}
/*
* If rewriting (RENAME), return the inode and the
* information required to rewrite the present directory
* Must get inode of directory entry to verify it's a
* regular file, or empty directory.
*/
if (nameiop == NAMEI_RENAME && wantparent) {
if (blkoff == MSDOSFSROOT_OFS)
return EROFS; /* really? XXX */
error = VOP_EACCESS(vdp, VWRITE, cnp->cn_cred);
if (error)
return (error);
/*
* Careful about locking second inode.
* This can only occur if the target is ".".
*/
if (dp->de_StartCluster == scn && isadir)
return (EISDIR);
if ((error = deget(pmp, cluster, blkoff, &tdp)) != 0)
return (error);
*vpp = DETOV(tdp);
if (!lockparent) {
vn_unlock(vdp);
cnp->cn_flags |= CNP_PDIRUNLOCK;
}
return (0);
}
/*
* Step through the translation in the name. We do not `vput' the
* directory because we may need it again if a symbolic link
* is relative to the current directory. Instead we save it
* unlocked as "pdp". We must get the target inode before unlocking
* the directory to insure that the inode will not be removed
* before we get it. We prevent deadlock by always fetching
* inodes from the root, moving down the directory tree. Thus
* when following backward pointers ".." we must unlock the
* parent directory before getting the requested directory.
* There is a potential race condition here if both the current
* and parent directories are removed before the VFS_VGET for the
* inode associated with ".." returns. We hope that this occurs
* infrequently since we cannot avoid this race condition without
* implementing a sophisticated deadlock detection algorithm.
* Note also that this simple deadlock detection scheme will not
* work if the file system has any hard links other than ".."
* that point backwards in the directory structure.
*/
pdp = vdp;
if (flags & CNP_ISDOTDOT) {
vn_unlock(pdp);
cnp->cn_flags |= CNP_PDIRUNLOCK;
error = deget(pmp, cluster, blkoff, &tdp);
if (error) {
vn_lock(pdp, LK_EXCLUSIVE | LK_RETRY);
cnp->cn_flags &= ~CNP_PDIRUNLOCK;
return (error);
}
if (lockparent) {
error = vn_lock(pdp, LK_EXCLUSIVE | LK_FAILRECLAIM);
if (error) {
vput(DETOV(tdp));
return (error);
}
cnp->cn_flags &= ~CNP_PDIRUNLOCK;
}
*vpp = DETOV(tdp);
} else if (dp->de_StartCluster == scn && isadir) {
vref(vdp); /* we want ourself, ie "." */
*vpp = vdp;
} else {
if ((error = deget(pmp, cluster, blkoff, &tdp)) != 0)
return (error);
if (!lockparent) {
vn_unlock(pdp);
cnp->cn_flags |= CNP_PDIRUNLOCK;
}
*vpp = DETOV(tdp);
}
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;
}
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);
}
/*
* 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);
}
int
msdosfs_mountfs(struct vnode *devvp, struct mount *mp, struct proc *p,
struct msdosfs_args *argp)
{
struct msdosfsmount *pmp;
struct buf *bp;
dev_t dev = devvp->v_rdev;
union bootsector *bsp;
struct byte_bpb33 *b33;
struct byte_bpb50 *b50;
struct byte_bpb710 *b710;
extern struct vnode *rootvp;
u_int8_t SecPerClust;
int ronly, error, bmapsiz;
uint32_t fat_max_clusters;
/*
* Disallow multiple mounts of the same device.
* Disallow mounting of a device that is currently in use
* (except for root, which might share swap device for miniroot).
* Flush out any old buffers remaining from a previous use.
*/
if ((error = vfs_mountedon(devvp)) != 0)
return (error);
if (vcount(devvp) > 1 && devvp != rootvp)
return (EBUSY);
vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, p);
error = vinvalbuf(devvp, V_SAVE, p->p_ucred, p, 0, 0);
VOP_UNLOCK(devvp, 0, p);
if (error)
return (error);
ronly = (mp->mnt_flag & MNT_RDONLY) != 0;
error = VOP_OPEN(devvp, ronly ? FREAD : FREAD|FWRITE, FSCRED, p);
if (error)
return (error);
bp = NULL; /* both used in error_exit */
pmp = NULL;
/*
* Read the boot sector of the filesystem, and then check the
* boot signature. If not a dos boot sector then error out.
*/
if ((error = bread(devvp, 0, 4096, NOCRED, &bp)) != 0)
goto error_exit;
bp->b_flags |= B_AGE;
bsp = (union bootsector *)bp->b_data;
b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB;
b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB;
b710 = (struct byte_bpb710 *)bsp->bs710.bsPBP;
pmp = malloc(sizeof *pmp, M_MSDOSFSMNT, M_WAITOK | M_ZERO);
pmp->pm_mountp = mp;
/*
* Compute several useful quantities from the bpb in the
* bootsector. Copy in the dos 5 variant of the bpb then fix up
* the fields that are different between dos 5 and dos 3.3.
*/
SecPerClust = b50->bpbSecPerClust;
pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec);
pmp->pm_ResSectors = getushort(b50->bpbResSectors);
pmp->pm_FATs = b50->bpbFATs;
pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts);
pmp->pm_Sectors = getushort(b50->bpbSectors);
pmp->pm_FATsecs = getushort(b50->bpbFATsecs);
pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack);
pmp->pm_Heads = getushort(b50->bpbHeads);
pmp->pm_Media = b50->bpbMedia;
/* Determine the number of DEV_BSIZE blocks in a MSDOSFS sector */
pmp->pm_BlkPerSec = pmp->pm_BytesPerSec / DEV_BSIZE;
if (!pmp->pm_BytesPerSec || !SecPerClust || pmp->pm_SecPerTrack > 64) {
error = EFTYPE;
goto error_exit;
}
if (pmp->pm_Sectors == 0) {
pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs);
pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors);
} else {
pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs);
pmp->pm_HugeSectors = pmp->pm_Sectors;
}
if (pmp->pm_RootDirEnts == 0) {
if (pmp->pm_Sectors || pmp->pm_FATsecs ||
getushort(b710->bpbFSVers)) {
error = EINVAL;
goto error_exit;
}
pmp->pm_fatmask = FAT32_MASK;
pmp->pm_fatmult = 4;
pmp->pm_fatdiv = 1;
pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs);
if (getushort(b710->bpbExtFlags) & FATMIRROR)
pmp->pm_curfat = getushort(b710->bpbExtFlags) & FATNUM;
else
pmp->pm_flags |= MSDOSFS_FATMIRROR;
} else
pmp->pm_flags |= MSDOSFS_FATMIRROR;
/*
* More sanity checks:
* MSDOSFS sectors per cluster: >0 && power of 2
* MSDOSFS sector size: >= DEV_BSIZE && power of 2
* HUGE sector count: >0
* FAT sectors: >0
*/
if ((SecPerClust == 0) || (SecPerClust & (SecPerClust - 1)) ||
(pmp->pm_BytesPerSec < DEV_BSIZE) ||
(pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1)) ||
(pmp->pm_HugeSectors == 0) || (pmp->pm_FATsecs == 0)) {
error = EINVAL;
goto error_exit;
}
pmp->pm_HugeSectors *= pmp->pm_BlkPerSec;
pmp->pm_HiddenSects *= pmp->pm_BlkPerSec;
pmp->pm_FATsecs *= pmp->pm_BlkPerSec;
pmp->pm_fatblk = pmp->pm_ResSectors * pmp->pm_BlkPerSec;
SecPerClust *= pmp->pm_BlkPerSec;
if (FAT32(pmp)) {
pmp->pm_rootdirblk = getulong(b710->bpbRootClust);
pmp->pm_firstcluster = pmp->pm_fatblk
+ (pmp->pm_FATs * pmp->pm_FATsecs);
pmp->pm_fsinfo = getushort(b710->bpbFSInfo) * pmp->pm_BlkPerSec;
} else {
pmp->pm_rootdirblk = pmp->pm_fatblk +
(pmp->pm_FATs * pmp->pm_FATsecs);
pmp->pm_rootdirsize = (pmp->pm_RootDirEnts * sizeof(struct direntry)
+ DEV_BSIZE - 1) / DEV_BSIZE;
pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize;
}
pmp->pm_nmbrofclusters = (pmp->pm_HugeSectors - pmp->pm_firstcluster) /
SecPerClust;
pmp->pm_maxcluster = pmp->pm_nmbrofclusters + 1;
pmp->pm_fatsize = pmp->pm_FATsecs * DEV_BSIZE;
if (pmp->pm_fatmask == 0) {
if (pmp->pm_maxcluster
<= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) {
/*
* This will usually be a floppy disk. This size makes
* sure that one fat entry will not be split across
* multiple blocks.
*/
pmp->pm_fatmask = FAT12_MASK;
pmp->pm_fatmult = 3;
pmp->pm_fatdiv = 2;
} else {
pmp->pm_fatmask = FAT16_MASK;
pmp->pm_fatmult = 2;
pmp->pm_fatdiv = 1;
}
}
if (FAT12(pmp))
pmp->pm_fatblocksize = 3 * pmp->pm_BytesPerSec;
else
pmp->pm_fatblocksize = MAXBSIZE;
/*
* We now have the number of sectors in each FAT, so can work
* out how many clusters can be represented in a FAT. Let's
* make sure the file system doesn't claim to have more clusters
* than this.
*
* We perform the calculation like we do to avoid integer overflow.
*
* This will give us a count of clusters. They are numbered
* from 0, so the max cluster value is one less than the value
* we end up with.
*/
fat_max_clusters = pmp->pm_fatsize / pmp->pm_fatmult;
fat_max_clusters *= pmp->pm_fatdiv;
if (pmp->pm_maxcluster >= fat_max_clusters) {
#ifndef SMALL_KERNEL
printf("msdosfs: reducing max cluster to %d from %d "
"due to FAT size\n", fat_max_clusters - 1,
pmp->pm_maxcluster);
#endif
pmp->pm_maxcluster = fat_max_clusters - 1;
}
pmp->pm_fatblocksec = pmp->pm_fatblocksize / DEV_BSIZE;
pmp->pm_bnshift = ffs(DEV_BSIZE) - 1;
/*
* Compute mask and shift value for isolating cluster relative byte
* offsets and cluster numbers from a file offset.
*/
pmp->pm_bpcluster = SecPerClust * DEV_BSIZE;
pmp->pm_crbomask = pmp->pm_bpcluster - 1;
pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1;
/*
* Check for valid cluster size
* must be a power of 2
*/
if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) {
error = EFTYPE;
goto error_exit;
}
/*
* Release the bootsector buffer.
*/
brelse(bp);
bp = NULL;
/*
* Check FSInfo
*/
if (pmp->pm_fsinfo) {
struct fsinfo *fp;
if ((error = bread(devvp, pmp->pm_fsinfo, fsi_size(pmp),
NOCRED, &bp)) != 0)
goto error_exit;
fp = (struct fsinfo *)bp->b_data;
if (!bcmp(fp->fsisig1, "RRaA", 4)
&& !bcmp(fp->fsisig2, "rrAa", 4)
&& !bcmp(fp->fsisig3, "\0\0\125\252", 4)
&& !bcmp(fp->fsisig4, "\0\0\125\252", 4))
/* Valid FSInfo. */
;
else
pmp->pm_fsinfo = 0;
/* XXX make sure this tiny buf doesn't come back in fillinusemap! */
SET(bp->b_flags, B_INVAL);
brelse(bp);
bp = NULL;
}
/*
* Check and validate (or perhaps invalidate?) the fsinfo structure? XXX
*/
/*
* Allocate memory for the bitmap of allocated clusters, and then
* fill it in.
*/
bmapsiz = (pmp->pm_maxcluster + N_INUSEBITS - 1) / N_INUSEBITS;
if (bmapsiz == 0 || SIZE_MAX / bmapsiz < sizeof(*pmp->pm_inusemap)) {
/* detect multiplicative integer overflow */
error = EINVAL;
goto error_exit;
}
pmp->pm_inusemap = malloc(bmapsiz * sizeof(*pmp->pm_inusemap),
M_MSDOSFSFAT, M_WAITOK | M_CANFAIL);
if (pmp->pm_inusemap == NULL) {
error = EINVAL;
goto error_exit;
}
/*
* fillinusemap() needs pm_devvp.
*/
pmp->pm_dev = dev;
pmp->pm_devvp = devvp;
/*
* Have the inuse map filled in.
*/
if ((error = fillinusemap(pmp)) != 0)
goto error_exit;
/*
* If they want fat updates to be synchronous then let them suffer
* the performance degradation in exchange for the on disk copy of
* the fat being correct just about all the time. I suppose this
* would be a good thing to turn on if the kernel is still flakey.
*/
if (mp->mnt_flag & MNT_SYNCHRONOUS)
pmp->pm_flags |= MSDOSFSMNT_WAITONFAT;
/*
* Finish up.
*/
if (ronly)
pmp->pm_flags |= MSDOSFSMNT_RONLY;
else
pmp->pm_fmod = 1;
mp->mnt_data = (qaddr_t)pmp;
mp->mnt_stat.f_fsid.val[0] = (long)dev;
mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum;
#ifdef QUOTA
/*
* If we ever do quotas for DOS filesystems this would be a place
* to fill in the info in the msdosfsmount structure. You dolt,
* quotas on dos filesystems make no sense because files have no
* owners on dos filesystems. of course there is some empty space
* in the directory entry where we could put uid's and gid's.
*/
#endif
devvp->v_specmountpoint = mp;
return (0);
error_exit:
devvp->v_specmountpoint = NULL;
if (bp)
brelse(bp);
vn_lock(devvp, LK_EXCLUSIVE|LK_RETRY, p);
(void) VOP_CLOSE(devvp, ronly ? FREAD : FREAD|FWRITE, NOCRED, p);
VOP_UNLOCK(devvp, 0, p);
if (pmp) {
if (pmp->pm_inusemap)
free(pmp->pm_inusemap, M_MSDOSFSFAT);
free(pmp, M_MSDOSFSMNT);
mp->mnt_data = (qaddr_t)0;
}
return (error);
}
/*
* 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);
}
/*
* If deget() succeeds it returns with the gotten denode locked().
*
* pmp - address of msdosfsmount structure of the filesystem containing
* the denode of interest. The pm_dev field and the address of
* the msdosfsmount structure are used.
* dirclust - which cluster bp contains, if dirclust is 0 (root directory)
* diroffset is relative to the beginning of the root directory,
* otherwise it is cluster relative.
* diroffset - offset past begin of cluster of denode we want
* depp - returns the address of the gotten denode.
*/
int
deget(struct msdosfsmount *pmp, uint32_t dirclust, uint32_t diroffset,
struct denode **depp)
{
int error;
extern struct vops msdosfs_vops;
struct direntry *direntptr;
struct denode *ldep;
struct vnode *nvp;
struct buf *bp;
struct proc *p = curproc; /* XXX */
#ifdef MSDOSFS_DEBUG
printf("deget(pmp %08x, dirclust %d, diroffset %x, depp %08x)\n",
pmp, dirclust, diroffset, depp);
#endif
/*
* On FAT32 filesystems, root is a (more or less) normal
* directory
*/
if (FAT32(pmp) && dirclust == MSDOSFSROOT)
dirclust = pmp->pm_rootdirblk;
/*
* See if the denode is in the denode cache. Use the location of
* the directory entry to compute the hash value. For subdir use
* address of "." entry. For root dir (if not FAT32) use cluster
* MSDOSFSROOT, offset MSDOSFSROOT_OFS
*
* NOTE: The check for de_refcnt > 0 below insures the denode being
* examined does not represent an unlinked but still open file.
* These files are not to be accessible even when the directory
* entry that represented the file happens to be reused while the
* deleted file is still open.
*/
retry:
ldep = msdosfs_hashget(pmp->pm_dev, dirclust, diroffset);
if (ldep) {
*depp = ldep;
return (0);
}
/*
* Directory entry was not in cache, have to create a vnode and
* copy it from the passed disk buffer.
*/
/* getnewvnode() does a vref() on the vnode */
error = getnewvnode(VT_MSDOSFS, pmp->pm_mountp, &msdosfs_vops, &nvp);
if (error) {
*depp = 0;
return (error);
}
ldep = malloc(sizeof(*ldep), M_MSDOSFSNODE, M_WAITOK | M_ZERO);
lockinit(&ldep->de_lock, PINOD, "denode", 0, 0);
nvp->v_data = ldep;
ldep->de_vnode = nvp;
ldep->de_flag = 0;
ldep->de_devvp = 0;
ldep->de_lockf = 0;
ldep->de_dev = pmp->pm_dev;
ldep->de_dirclust = dirclust;
ldep->de_diroffset = diroffset;
fc_purge(ldep, 0); /* init the fat cache for this denode */
/*
* Insert the denode into the hash queue and lock the denode so it
* can't be accessed until we've read it in and have done what we
* need to it.
*/
vn_lock(nvp, LK_EXCLUSIVE | LK_RETRY, p);
error = msdosfs_hashins(ldep);
if (error) {
vput (nvp);
if (error == EEXIST)
goto retry;
return (error);
}
ldep->de_pmp = pmp;
ldep->de_devvp = pmp->pm_devvp;
ldep->de_refcnt = 1;
/*
* Copy the directory entry into the denode area of the vnode.
*/
if ((dirclust == MSDOSFSROOT
|| (FAT32(pmp) && dirclust == pmp->pm_rootdirblk))
&& diroffset == MSDOSFSROOT_OFS) {
/*
* Directory entry for the root directory. There isn't one,
* so we manufacture one. We should probably rummage
* through the root directory and find a label entry (if it
* exists), and then use the time and date from that entry
* as the time and date for the root denode.
*/
nvp->v_flag |= VROOT; /* should be further down XXX */
ldep->de_Attributes = ATTR_DIRECTORY;
if (FAT32(pmp))
ldep->de_StartCluster = pmp->pm_rootdirblk;
/* de_FileSize will be filled in further down */
else {
ldep->de_StartCluster = MSDOSFSROOT;
ldep->de_FileSize = pmp->pm_rootdirsize * pmp->pm_BytesPerSec;
}
/*
* fill in time and date so that dos2unixtime() doesn't
* spit up when called from msdosfs_getattr() with root
* denode
*/
ldep->de_CTime = 0x0000; /* 00:00:00 */
ldep->de_CTimeHundredth = 0;
ldep->de_CDate = (0 << DD_YEAR_SHIFT) | (1 << DD_MONTH_SHIFT)
| (1 << DD_DAY_SHIFT);
/* Jan 1, 1980 */
ldep->de_ADate = ldep->de_CDate;
ldep->de_MTime = ldep->de_CTime;
ldep->de_MDate = ldep->de_CDate;
/* leave the other fields as garbage */
} else {
error = readep(pmp, dirclust, diroffset, &bp, &direntptr);
if (error)
return (error);
DE_INTERNALIZE(ldep, direntptr);
brelse(bp);
}
/*
* Fill in a few fields of the vnode and finish filling in the
* denode. Then return the address of the found denode.
*/
if (ldep->de_Attributes & ATTR_DIRECTORY) {
/*
* Since DOS directory entries that describe directories
* have 0 in the filesize field, we take this opportunity
* to find out the length of the directory and plug it into
* the denode structure.
*/
uint32_t size;
nvp->v_type = VDIR;
if (ldep->de_StartCluster != MSDOSFSROOT) {
error = pcbmap(ldep, 0xffff, 0, &size, 0);
if (error == E2BIG) {
ldep->de_FileSize = de_cn2off(pmp, size);
error = 0;
} else if (error) {
printf("deget(): pcbmap returned %d\n", error);
return (error);
}
}
} else
nvp->v_type = VREG;
vref(ldep->de_devvp);
*depp = ldep;
return (0);
}
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);
}
/*
* 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;
}
}
/*
* If deget() succeeds it returns with the gotten denode locked().
*
* pmp - address of msdosfsmount structure of the filesystem containing
* the denode of interest. The pm_dev field and the address of
* the msdosfsmount structure are used.
* dirclust - which cluster bp contains, if dirclust is 0 (root directory)
* diroffset is relative to the beginning of the root directory,
* otherwise it is cluster relative.
* diroffset - offset past begin of cluster of denode we want
* depp - returns the address of the gotten denode.
*/
int
deget(struct msdosfsmount *pmp, u_long dirclust, u_long diroffset,
struct denode **depp)
/* pmp: so we know the maj/min number */
/* dirclust: cluster this dir entry came from */
/* diroffset: index of entry within the cluster */
/* depp: returns the addr of the gotten denode */
{
int error;
struct direntry *direntptr;
struct denode *ldep;
struct buf *bp;
#ifdef MSDOSFS_DEBUG
printf("deget(pmp %p, dirclust %lu, diroffset %lx, depp %p)\n",
pmp, dirclust, diroffset, depp);
#endif
/*
* On FAT32 filesystems, root is a (more or less) normal
* directory
*/
if (FAT32(pmp) && dirclust == MSDOSFSROOT)
dirclust = pmp->pm_rootdirblk;
ldep = ecalloc(1, sizeof(*ldep));
ldep->de_vnode = NULL;
ldep->de_flag = 0;
ldep->de_devvp = 0;
ldep->de_lockf = 0;
ldep->de_dev = pmp->pm_dev;
ldep->de_dirclust = dirclust;
ldep->de_diroffset = diroffset;
ldep->de_pmp = pmp;
ldep->de_devvp = pmp->pm_devvp;
ldep->de_refcnt = 1;
fc_purge(ldep, 0);
/*
* Copy the directory entry into the denode area of the vnode.
*/
if ((dirclust == MSDOSFSROOT
|| (FAT32(pmp) && dirclust == pmp->pm_rootdirblk))
&& diroffset == MSDOSFSROOT_OFS) {
/*
* Directory entry for the root directory. There isn't one,
* so we manufacture one. We should probably rummage
* through the root directory and find a label entry (if it
* exists), and then use the time and date from that entry
* as the time and date for the root denode.
*/
ldep->de_vnode = (struct vnode *)-1;
ldep->de_Attributes = ATTR_DIRECTORY;
if (FAT32(pmp))
ldep->de_StartCluster = pmp->pm_rootdirblk;
/* de_FileSize will be filled in further down */
else {
ldep->de_StartCluster = MSDOSFSROOT;
ldep->de_FileSize = pmp->pm_rootdirsize * pmp->pm_BytesPerSec;
}
/*
* fill in time and date so that dos2unixtime() doesn't
* spit up when called from msdosfs_getattr() with root
* denode
*/
ldep->de_CHun = 0;
ldep->de_CTime = 0x0000; /* 00:00:00 */
ldep->de_CDate = (0 << DD_YEAR_SHIFT) | (1 << DD_MONTH_SHIFT)
| (1 << DD_DAY_SHIFT);
/* Jan 1, 1980 */
ldep->de_ADate = ldep->de_CDate;
ldep->de_MTime = ldep->de_CTime;
ldep->de_MDate = ldep->de_CDate;
/* leave the other fields as garbage */
} else {
error = readep(pmp, dirclust, diroffset, &bp, &direntptr);
if (error) {
ldep->de_devvp = NULL;
ldep->de_Name[0] = SLOT_DELETED;
return (error);
}
DE_INTERNALIZE(ldep, direntptr);
brelse(bp, 0);
}
/*
* Fill in a few fields of the vnode and finish filling in the
* denode. Then return the address of the found denode.
*/
if (ldep->de_Attributes & ATTR_DIRECTORY) {
/*
* Since DOS directory entries that describe directories
* have 0 in the filesize field, we take this opportunity
* to find out the length of the directory and plug it into
* the denode structure.
*/
u_long size;
if (ldep->de_StartCluster != MSDOSFSROOT) {
error = pcbmap(ldep, CLUST_END, 0, &size, 0);
if (error == E2BIG) {
ldep->de_FileSize = de_cn2off(pmp, size);
error = 0;
} else
printf("deget(): pcbmap returned %d\n", error);
}
}
*depp = ldep;
return (0);
}
/*
* When we search a directory the blocks containing directory entries are
* read and examined. The directory entries contain information that would
* normally be in the inode of a unix filesystem. This means that some of
* a directory's contents may also be in memory resident denodes (sort of
* an inode). This can cause problems if we are searching while some other
* process is modifying a directory. To prevent one process from accessing
* incompletely modified directory information we depend upon being the
* sole owner of a directory block. bread/brelse provide this service.
* This being the case, when a process modifies a directory it must first
* acquire the disk block that contains the directory entry to be modified.
* Then update the disk block and the denode, and then write the disk block
* out to disk. This way disk blocks containing directory entries and in
* memory denode's will be in synch.
*/
int
msdosfs_lookup(void *v)
{
struct vop_lookup_v2_args /* {
struct vnode *a_dvp;
struct vnode **a_vpp;
struct componentname *a_cnp;
} */ *ap = v;
struct vnode *vdp = ap->a_dvp;
struct vnode **vpp = ap->a_vpp;
struct componentname *cnp = ap->a_cnp;
daddr_t bn;
int error;
int slotcount;
int slotoffset = 0;
int frcn;
u_long cluster;
int blkoff;
int diroff;
int blsize;
int isadir; /* ~0 if found direntry is a directory */
u_long scn; /* starting cluster number */
struct vnode *pdp;
struct denode *dp;
struct denode *tdp;
struct msdosfsmount *pmp;
struct buf *bp = 0;
struct direntry *dep;
u_char dosfilename[12];
int flags;
int nameiop = cnp->cn_nameiop;
int wincnt = 1;
int chksum = -1, chksum_ok;
int olddos = 1;
flags = cnp->cn_flags;
#ifdef MSDOSFS_DEBUG
printf("msdosfs_lookup(): looking for %.*s\n",
(int)cnp->cn_namelen, cnp->cn_nameptr);
#endif
dp = VTODE(vdp);
pmp = dp->de_pmp;
*vpp = NULL;
#ifdef MSDOSFS_DEBUG
printf("msdosfs_lookup(): vdp %p, dp %p, Attr %02x\n",
vdp, dp, dp->de_Attributes);
#endif
/*
* Check accessiblity of directory.
*/
if ((error = VOP_ACCESS(vdp, VEXEC, cnp->cn_cred)) != 0)
return (error);
if ((flags & ISLASTCN) && (vdp->v_mount->mnt_flag & MNT_RDONLY) &&
(cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME))
return (EROFS);
/*
* We now have a segment name to search for, and a directory to search.
*
* Before tediously performing a linear scan of the directory,
* check the name cache to see if the directory/name pair
* we are looking for is known already.
*/
if (cache_lookup(vdp, cnp->cn_nameptr, cnp->cn_namelen,
cnp->cn_nameiop, cnp->cn_flags, NULL, vpp)) {
return *vpp == NULLVP ? ENOENT: 0;
}
/*
* If they are going after the . or .. entry in the root directory,
* they won't find it. DOS filesystems don't have them in the root
* directory. So, we fake it. deget() is in on this scam too.
*/
if ((vdp->v_vflag & VV_ROOT) && cnp->cn_nameptr[0] == '.' &&
(cnp->cn_namelen == 1 ||
(cnp->cn_namelen == 2 && cnp->cn_nameptr[1] == '.'))) {
isadir = ATTR_DIRECTORY;
scn = MSDOSFSROOT;
#ifdef MSDOSFS_DEBUG
printf("msdosfs_lookup(): looking for . or .. in root directory\n");
#endif
cluster = MSDOSFSROOT;
blkoff = MSDOSFSROOT_OFS;
goto foundroot;
}
switch (unix2dosfn((const u_char *)cnp->cn_nameptr, dosfilename,
cnp->cn_namelen, 0)) {
case 0:
return (EINVAL);
case 1:
break;
case 2:
wincnt = winSlotCnt((const u_char *)cnp->cn_nameptr,
cnp->cn_namelen) + 1;
break;
case 3:
olddos = 0;
wincnt = winSlotCnt((const u_char *)cnp->cn_nameptr,
cnp->cn_namelen) + 1;
break;
}
if (pmp->pm_flags & MSDOSFSMNT_SHORTNAME)
wincnt = 1;
/*
* Suppress search for slots unless creating
* file and at end of pathname, in which case
* we watch for a place to put the new file in
* case it doesn't already exist.
*/
slotcount = wincnt;
if ((nameiop == CREATE || nameiop == RENAME) &&
(flags & ISLASTCN))
slotcount = 0;
#ifdef MSDOSFS_DEBUG
printf("msdosfs_lookup(): dos filename: %s\n", dosfilename);
#endif
/*
* Search the directory pointed at by vdp for the name pointed at
* by cnp->cn_nameptr.
*/
tdp = NULL;
/*
* The outer loop ranges over the clusters that make up the
* directory. Note that the root directory is different from all
* other directories. It has a fixed number of blocks that are not
* part of the pool of allocatable clusters. So, we treat it a
* little differently. The root directory starts at "cluster" 0.
*/
diroff = 0;
for (frcn = 0; diroff < dp->de_FileSize; frcn++) {
if ((error = pcbmap(dp, frcn, &bn, &cluster, &blsize)) != 0) {
if (error == E2BIG)
break;
return (error);
}
error = bread(pmp->pm_devvp, de_bn2kb(pmp, bn), blsize, NOCRED,
0, &bp);
if (error) {
return (error);
}
for (blkoff = 0; blkoff < blsize;
blkoff += sizeof(struct direntry),
diroff += sizeof(struct direntry)) {
dep = (struct direntry *)((char *)bp->b_data + blkoff);
/*
* If the slot is empty and we are still looking
* for an empty then remember this one. If the
* slot is not empty then check to see if it
* matches what we are looking for. If the slot
* has never been filled with anything, then the
* remainder of the directory has never been used,
* so there is no point in searching it.
*/
if (dep->deName[0] == SLOT_EMPTY ||
dep->deName[0] == SLOT_DELETED) {
/*
* Drop memory of previous long matches
*/
chksum = -1;
if (slotcount < wincnt) {
slotcount++;
slotoffset = diroff;
}
if (dep->deName[0] == SLOT_EMPTY) {
brelse(bp, 0);
goto notfound;
}
} else {
/*
* If there wasn't enough space for our
* winentries, forget about the empty space
*/
if (slotcount < wincnt)
slotcount = 0;
/*
* Check for Win95 long filename entry
*/
if (dep->deAttributes == ATTR_WIN95) {
if (pmp->pm_flags & MSDOSFSMNT_SHORTNAME)
continue;
chksum = winChkName((const u_char *)cnp->cn_nameptr,
cnp->cn_namelen,
(struct winentry *)dep,
chksum);
continue;
}
/*
* Ignore volume labels (anywhere, not just
* the root directory).
*/
if (dep->deAttributes & ATTR_VOLUME) {
chksum = -1;
continue;
}
/*
* Check for a checksum or name match
*/
chksum_ok = (chksum == winChksum(dep->deName));
if (!chksum_ok && (
!olddos ||
memcmp(&dosfilename[0],dep->deName,8) ||
memcmp(&dosfilename[8],dep->deExtension,3))) {
chksum = -1;
continue;
}
#ifdef MSDOSFS_DEBUG
printf("msdosfs_lookup(): match blkoff %d, diroff %d\n",
blkoff, diroff);
#endif
/*
* Remember where this directory
* entry came from for whoever did
* this lookup.
*/
dp->de_fndoffset = diroff;
if (chksum_ok && nameiop == RENAME) {
/*
* Target had correct long name
* directory entries, reuse them
* as needed.
*/
dp->de_fndcnt = wincnt - 1;
} else {
/*
* Long name directory entries
* not present or corrupt, can only
* reuse dos directory entry.
*/
dp->de_fndcnt = 0;
}
goto found;
}
} /* for (blkoff = 0; .... */
/*
* Release the buffer holding the directory cluster just
* searched.
*/
brelse(bp, 0);
} /* for (frcn = 0; ; frcn++) */
notfound:
/*
* We hold no disk buffers at this point.
*/
/*
* If we get here we didn't find the entry we were looking for. But
* that's ok if we are creating or renaming and are at the end of
* the pathname and the directory hasn't been removed.
*/
#ifdef MSDOSFS_DEBUG
printf("msdosfs_lookup(): op %d, refcnt %ld, slotcount %d, slotoffset %d\n",
nameiop, dp->de_refcnt, slotcount, slotoffset);
#endif
if ((nameiop == CREATE || nameiop == RENAME) &&
(flags & ISLASTCN) && dp->de_refcnt != 0) {
/*
* Access for write is interpreted as allowing
* creation of files in the directory.
*/
error = VOP_ACCESS(vdp, VWRITE, cnp->cn_cred);
if (error)
return (error);
/*
* Fixup the slot description to point to the place where
* we might put the new DOS direntry (putting the Win95
* long name entries before that)
*/
if (!slotcount) {
slotcount = 1;
slotoffset = diroff;
}
if (wincnt > slotcount) {
slotoffset +=
sizeof(struct direntry) * (wincnt - slotcount);
}
/*
* Return an indication of where the new directory
* entry should be put.
*/
dp->de_fndoffset = slotoffset;
dp->de_fndcnt = wincnt - 1;
/*
* We return with the directory locked, so that
* the parameters we set up above will still be
* valid if we actually decide to do a direnter().
* We return ni_vp == NULL to indicate that the entry
* does not currently exist; we leave a pointer to
* the (locked) directory inode in ndp->ni_dvp.
*
* NB - if the directory is unlocked, then this
* information cannot be used.
*/
return (EJUSTRETURN);
}
#if 0
/*
* Insert name into cache (as non-existent) if appropriate.
*
* XXX Negative caching is broken for msdosfs because the name
* cache doesn't understand peculiarities such as case insensitivity
* and 8.3 filenames. Hence, it may not invalidate all negative
* entries if a file with this name is later created.
* e.g. creating a file 'foo' won't invalidate a negative entry
* for 'FOO'.
*/
if (nameiop != CREATE)
cache_enter(vdp, *vpp, cnp->cn_nameptr, cnp->cn_namelen,
cnp->cn_flags);
#endif
return (ENOENT);
found:
/*
* NOTE: We still have the buffer with matched directory entry at
* this point.
*/
isadir = dep->deAttributes & ATTR_DIRECTORY;
scn = getushort(dep->deStartCluster);
if (FAT32(pmp)) {
scn |= getushort(dep->deHighClust) << 16;
if (scn == pmp->pm_rootdirblk) {
/*
* There should actually be 0 here.
* Just ignore the error.
*/
scn = MSDOSFSROOT;
}
}
if (isadir) {
cluster = scn;
if (cluster == MSDOSFSROOT)
blkoff = MSDOSFSROOT_OFS;
else
blkoff = 0;
} else if (cluster == MSDOSFSROOT)
blkoff = diroff;
/*
* Now release buf to allow deget to read the entry again.
* Reserving it here and giving it to deget could result
* in a deadlock.
*/
brelse(bp, 0);
foundroot:
/*
* If we entered at foundroot, then we are looking for the . or ..
* entry of the filesystems root directory. isadir and scn were
* setup before jumping here. And, bp is already null.
*/
if (FAT32(pmp) && scn == MSDOSFSROOT)
scn = pmp->pm_rootdirblk;
/*
* If deleting, and at end of pathname, return
* parameters which can be used to remove file.
* Lock the inode, being careful with ".".
*/
if (nameiop == DELETE && (flags & ISLASTCN)) {
/*
* Don't allow deleting the root.
*/
if (blkoff == MSDOSFSROOT_OFS)
return EINVAL;
/*
* Write access to directory required to delete files.
*/
error = VOP_ACCESS(vdp, VWRITE, cnp->cn_cred);
if (error)
return (error);
/*
* Return pointer to current entry in dp->i_offset.
* Save directory inode pointer in ndp->ni_dvp for dirremove().
*/
if (dp->de_StartCluster == scn && isadir) { /* "." */
vref(vdp);
*vpp = vdp;
return (0);
}
if ((error = deget(pmp, cluster, blkoff, &tdp)) != 0)
return (error);
*vpp = DETOV(tdp);
VOP_UNLOCK(*vpp);
return (0);
}
/*
* If rewriting (RENAME), return the inode and the
* information required to rewrite the present directory
* Must get inode of directory entry to verify it's a
* regular file, or empty directory.
*/
if (nameiop == RENAME && (flags & ISLASTCN)) {
if (vdp->v_mount->mnt_flag & MNT_RDONLY)
return (EROFS);
if (blkoff == MSDOSFSROOT_OFS)
return EINVAL;
error = VOP_ACCESS(vdp, VWRITE, cnp->cn_cred);
if (error)
return (error);
/*
* Careful about locking second inode.
* This can only occur if the target is ".".
*/
if (dp->de_StartCluster == scn && isadir)
return (EISDIR);
if ((error = deget(pmp, cluster, blkoff, &tdp)) != 0)
return (error);
*vpp = DETOV(tdp);
VOP_UNLOCK(*vpp);
return (0);
}
/*
* Step through the translation in the name. We do not `vput' the
* directory because we may need it again if a symbolic link
* is relative to the current directory. Instead we save it
* unlocked as "pdp". We must get the target inode before unlocking
* the directory to insure that the inode will not be removed
* before we get it. We prevent deadlock by always fetching
* inodes from the root, moving down the directory tree. Thus
* when following backward pointers ".." we must unlock the
* parent directory before getting the requested directory.
* There is a potential race condition here if both the current
* and parent directories are removed before the VFS_VGET for the
* inode associated with ".." returns. We hope that this occurs
* infrequently since we cannot avoid this race condition without
* implementing a sophisticated deadlock detection algorithm.
* Note also that this simple deadlock detection scheme will not
* work if the file system has any hard links other than ".."
* that point backwards in the directory structure.
*/
pdp = vdp;
if (flags & ISDOTDOT) {
VOP_UNLOCK(pdp); /* race to get the inode */
error = deget(pmp, cluster, blkoff, &tdp);
vn_lock(pdp, LK_EXCLUSIVE | LK_RETRY);
if (error) {
return error;
}
*vpp = DETOV(tdp);
} else if (dp->de_StartCluster == scn && isadir) {
vref(vdp); /* we want ourself, ie "." */
*vpp = vdp;
} else {
if ((error = deget(pmp, cluster, blkoff, &tdp)) != 0)
return (error);
*vpp = DETOV(tdp);
}
/*
* Insert name into cache if appropriate.
*/
cache_enter(vdp, *vpp, cnp->cn_nameptr, cnp->cn_namelen, cnp->cn_flags);
if (*vpp != vdp)
VOP_UNLOCK(*vpp);
return 0;
}
int
msdosfs_mountfs(struct vnode *devvp, struct mount *mp, struct lwp *l, struct msdosfs_args *argp)
{
struct msdosfsmount *pmp;
struct buf *bp;
dev_t dev = devvp->v_rdev;
union bootsector *bsp;
struct byte_bpb33 *b33;
struct byte_bpb50 *b50;
struct byte_bpb710 *b710;
uint8_t SecPerClust;
int ronly, error, tmp;
int bsize;
uint64_t psize;
unsigned secsize;
/* Flush out any old buffers remaining from a previous use. */
if ((error = vinvalbuf(devvp, V_SAVE, l->l_cred, l, 0, 0)) != 0)
return (error);
ronly = (mp->mnt_flag & MNT_RDONLY) != 0;
bp = NULL; /* both used in error_exit */
pmp = NULL;
error = fstrans_mount(mp);
if (error)
goto error_exit;
error = getdisksize(devvp, &psize, &secsize);
if (error) {
if (argp->flags & MSDOSFSMNT_GEMDOSFS)
goto error_exit;
/* ok, so it failed. we most likely don't need the info */
secsize = DEV_BSIZE;
psize = 0;
error = 0;
}
if (argp->flags & MSDOSFSMNT_GEMDOSFS) {
bsize = secsize;
if (bsize != 512) {
DPRINTF(("Invalid block bsize %d for GEMDOS\n", bsize));
error = EINVAL;
goto error_exit;
}
} else
bsize = 0;
/*
* Read the boot sector of the filesystem, and then check the
* boot signature. If not a dos boot sector then error out.
*/
if ((error = bread(devvp, 0, secsize, NOCRED, 0, &bp)) != 0)
goto error_exit;
bsp = (union bootsector *)bp->b_data;
b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB;
b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB;
b710 = (struct byte_bpb710 *)bsp->bs710.bsBPB;
if (!(argp->flags & MSDOSFSMNT_GEMDOSFS)) {
if (bsp->bs50.bsBootSectSig0 != BOOTSIG0
|| bsp->bs50.bsBootSectSig1 != BOOTSIG1) {
DPRINTF(("bootsig0 %d bootsig1 %d\n",
bsp->bs50.bsBootSectSig0,
bsp->bs50.bsBootSectSig1));
error = EINVAL;
goto error_exit;
}
}
pmp = malloc(sizeof *pmp, M_MSDOSFSMNT, M_WAITOK);
memset(pmp, 0, sizeof *pmp);
pmp->pm_mountp = mp;
/*
* Compute several useful quantities from the bpb in the
* bootsector. Copy in the dos 5 variant of the bpb then fix up
* the fields that are different between dos 5 and dos 3.3.
*/
SecPerClust = b50->bpbSecPerClust;
pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec);
pmp->pm_ResSectors = getushort(b50->bpbResSectors);
pmp->pm_FATs = b50->bpbFATs;
pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts);
pmp->pm_Sectors = getushort(b50->bpbSectors);
pmp->pm_FATsecs = getushort(b50->bpbFATsecs);
pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack);
pmp->pm_Heads = getushort(b50->bpbHeads);
pmp->pm_Media = b50->bpbMedia;
if (!(argp->flags & MSDOSFSMNT_GEMDOSFS)) {
/* XXX - We should probably check more values here */
if (!pmp->pm_BytesPerSec || !SecPerClust
|| pmp->pm_SecPerTrack > 63) {
DPRINTF(("bytespersec %d secperclust %d "
"secpertrack %d\n",
pmp->pm_BytesPerSec, SecPerClust,
pmp->pm_SecPerTrack));
error = EINVAL;
goto error_exit;
}
}
if (pmp->pm_Sectors == 0) {
pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs);
pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors);
} else {
pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs);
pmp->pm_HugeSectors = pmp->pm_Sectors;
}
if (pmp->pm_RootDirEnts == 0) {
unsigned short vers = getushort(b710->bpbFSVers);
/*
* Some say that bsBootSectSig[23] must be zero, but
* Windows does not require this and some digital cameras
* do not set these to zero. Therefore, do not insist.
*/
if (pmp->pm_Sectors || pmp->pm_FATsecs || vers) {
DPRINTF(("sectors %d fatsecs %lu vers %d\n",
pmp->pm_Sectors, pmp->pm_FATsecs, vers));
error = EINVAL;
goto error_exit;
}
pmp->pm_fatmask = FAT32_MASK;
pmp->pm_fatmult = 4;
pmp->pm_fatdiv = 1;
pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs);
/* mirrorring is enabled if the FATMIRROR bit is not set */
if ((getushort(b710->bpbExtFlags) & FATMIRROR) == 0)
pmp->pm_flags |= MSDOSFS_FATMIRROR;
else
pmp->pm_curfat = getushort(b710->bpbExtFlags) & FATNUM;
} else
pmp->pm_flags |= MSDOSFS_FATMIRROR;
if (argp->flags & MSDOSFSMNT_GEMDOSFS) {
if (FAT32(pmp)) {
DPRINTF(("FAT32 for GEMDOS\n"));
/*
* GEMDOS doesn't know FAT32.
*/
error = EINVAL;
goto error_exit;
}
/*
* Check a few values (could do some more):
* - logical sector size: power of 2, >= block size
* - sectors per cluster: power of 2, >= 1
* - number of sectors: >= 1, <= size of partition
*/
if ( (SecPerClust == 0)
|| (SecPerClust & (SecPerClust - 1))
|| (pmp->pm_BytesPerSec < bsize)
|| (pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1))
|| (pmp->pm_HugeSectors == 0)
|| (pmp->pm_HugeSectors * (pmp->pm_BytesPerSec / bsize)
> psize)) {
DPRINTF(("consistency checks for GEMDOS\n"));
error = EINVAL;
goto error_exit;
}
/*
* XXX - Many parts of the msdosfs driver seem to assume that
* the number of bytes per logical sector (BytesPerSec) will
* always be the same as the number of bytes per disk block
* Let's pretend it is.
*/
tmp = pmp->pm_BytesPerSec / bsize;
pmp->pm_BytesPerSec = bsize;
pmp->pm_HugeSectors *= tmp;
pmp->pm_HiddenSects *= tmp;
pmp->pm_ResSectors *= tmp;
pmp->pm_Sectors *= tmp;
pmp->pm_FATsecs *= tmp;
SecPerClust *= tmp;
}
/* Check that fs has nonzero FAT size */
if (pmp->pm_FATsecs == 0) {
DPRINTF(("FATsecs is 0\n"));
error = EINVAL;
goto error_exit;
}
pmp->pm_fatblk = pmp->pm_ResSectors;
if (FAT32(pmp)) {
pmp->pm_rootdirblk = getulong(b710->bpbRootClust);
pmp->pm_firstcluster = pmp->pm_fatblk
+ (pmp->pm_FATs * pmp->pm_FATsecs);
pmp->pm_fsinfo = getushort(b710->bpbFSInfo);
} else {
pmp->pm_rootdirblk = pmp->pm_fatblk +
(pmp->pm_FATs * pmp->pm_FATsecs);
pmp->pm_rootdirsize = (pmp->pm_RootDirEnts * sizeof(struct direntry)
+ pmp->pm_BytesPerSec - 1)
/ pmp->pm_BytesPerSec;/* in sectors */
pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize;
}
pmp->pm_nmbrofclusters = (pmp->pm_HugeSectors - pmp->pm_firstcluster) /
SecPerClust;
pmp->pm_maxcluster = pmp->pm_nmbrofclusters + 1;
pmp->pm_fatsize = pmp->pm_FATsecs * pmp->pm_BytesPerSec;
if (argp->flags & MSDOSFSMNT_GEMDOSFS) {
if (pmp->pm_nmbrofclusters <= (0xff0 - 2)) {
pmp->pm_fatmask = FAT12_MASK;
pmp->pm_fatmult = 3;
pmp->pm_fatdiv = 2;
} else {
pmp->pm_fatmask = FAT16_MASK;
pmp->pm_fatmult = 2;
pmp->pm_fatdiv = 1;
}
} else if (pmp->pm_fatmask == 0) {
if (pmp->pm_maxcluster
<= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) {
/*
* This will usually be a floppy disk. This size makes
* sure that one FAT entry will not be split across
* multiple blocks.
*/
pmp->pm_fatmask = FAT12_MASK;
pmp->pm_fatmult = 3;
pmp->pm_fatdiv = 2;
} else {
pmp->pm_fatmask = FAT16_MASK;
pmp->pm_fatmult = 2;
pmp->pm_fatdiv = 1;
}
}
if (FAT12(pmp))
pmp->pm_fatblocksize = 3 * pmp->pm_BytesPerSec;
else
pmp->pm_fatblocksize = MAXBSIZE;
pmp->pm_fatblocksec = pmp->pm_fatblocksize / pmp->pm_BytesPerSec;
pmp->pm_bnshift = ffs(pmp->pm_BytesPerSec) - 1;
/*
* Compute mask and shift value for isolating cluster relative byte
* offsets and cluster numbers from a file offset.
*/
pmp->pm_bpcluster = SecPerClust * pmp->pm_BytesPerSec;
pmp->pm_crbomask = pmp->pm_bpcluster - 1;
pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1;
/*
* Check for valid cluster size
* must be a power of 2
*/
if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) {
DPRINTF(("bpcluster %lu cnshift %lu\n",
pmp->pm_bpcluster, pmp->pm_cnshift));
error = EINVAL;
goto error_exit;
}
/*
* Cluster size must be within limit of MAXBSIZE.
* Many FAT filesystems will not have clusters larger than
* 32KiB due to limits in Windows versions before Vista.
*/
if (pmp->pm_bpcluster > MAXBSIZE) {
DPRINTF(("bpcluster %lu > MAXBSIZE %d\n",
pmp->pm_bpcluster, MAXBSIZE));
error = EINVAL;
goto error_exit;
}
/*
* Release the bootsector buffer.
*/
brelse(bp, BC_AGE);
bp = NULL;
/*
* Check FSInfo.
*/
if (pmp->pm_fsinfo) {
struct fsinfo *fp;
/*
* XXX If the fsinfo block is stored on media with
* 2KB or larger sectors, is the fsinfo structure
* padded at the end or in the middle?
*/
if ((error = bread(devvp, de_bn2kb(pmp, pmp->pm_fsinfo),
pmp->pm_BytesPerSec, NOCRED, 0, &bp)) != 0)
goto error_exit;
fp = (struct fsinfo *)bp->b_data;
if (!memcmp(fp->fsisig1, "RRaA", 4)
&& !memcmp(fp->fsisig2, "rrAa", 4)
&& !memcmp(fp->fsisig3, "\0\0\125\252", 4)
&& !memcmp(fp->fsisig4, "\0\0\125\252", 4))
pmp->pm_nxtfree = getulong(fp->fsinxtfree);
else
pmp->pm_fsinfo = 0;
brelse(bp, 0);
bp = NULL;
}
/*
* Check and validate (or perhaps invalidate?) the fsinfo structure?
* XXX
*/
if (pmp->pm_fsinfo) {
if ((pmp->pm_nxtfree == 0xffffffffUL) ||
(pmp->pm_nxtfree > pmp->pm_maxcluster))
pmp->pm_fsinfo = 0;
}
/*
* Allocate memory for the bitmap of allocated clusters, and then
* fill it in.
*/
pmp->pm_inusemap = malloc(((pmp->pm_maxcluster + N_INUSEBITS)
/ N_INUSEBITS)
* sizeof(*pmp->pm_inusemap),
M_MSDOSFSFAT, M_WAITOK);
/*
* fillinusemap() needs pm_devvp.
*/
pmp->pm_dev = dev;
pmp->pm_devvp = devvp;
/*
* Have the inuse map filled in.
*/
if ((error = fillinusemap(pmp)) != 0) {
DPRINTF(("fillinusemap %d\n", error));
goto error_exit;
}
/*
* If they want FAT updates to be synchronous then let them suffer
* the performance degradation in exchange for the on disk copy of
* the FAT being correct just about all the time. I suppose this
* would be a good thing to turn on if the kernel is still flakey.
*/
if (mp->mnt_flag & MNT_SYNCHRONOUS)
pmp->pm_flags |= MSDOSFSMNT_WAITONFAT;
/*
* Finish up.
*/
if (ronly)
pmp->pm_flags |= MSDOSFSMNT_RONLY;
else
pmp->pm_fmod = 1;
mp->mnt_data = pmp;
mp->mnt_stat.f_fsidx.__fsid_val[0] = (long)dev;
mp->mnt_stat.f_fsidx.__fsid_val[1] = makefstype(MOUNT_MSDOS);
mp->mnt_stat.f_fsid = mp->mnt_stat.f_fsidx.__fsid_val[0];
mp->mnt_stat.f_namemax = MSDOSFS_NAMEMAX(pmp);
mp->mnt_flag |= MNT_LOCAL;
mp->mnt_dev_bshift = pmp->pm_bnshift;
mp->mnt_fs_bshift = pmp->pm_cnshift;
/*
* If we ever do quotas for DOS filesystems this would be a place
* to fill in the info in the msdosfsmount structure. You dolt,
* quotas on dos filesystems make no sense because files have no
* owners on dos filesystems. of course there is some empty space
* in the directory entry where we could put uid's and gid's.
*/
spec_node_setmountedfs(devvp, mp);
return (0);
error_exit:
fstrans_unmount(mp);
if (bp)
brelse(bp, BC_AGE);
if (pmp) {
if (pmp->pm_inusemap)
free(pmp->pm_inusemap, M_MSDOSFSFAT);
free(pmp, M_MSDOSFSMNT);
mp->mnt_data = NULL;
}
return (error);
}
/*
* mp - path - addr in user space of mount point (ie /usr or whatever)
* data - addr in user space of mount params including the name of the block
* special file to treat as a filesystem.
*/
int
msdosfs_mount(struct mount *mp, const char *path, void *data,
struct nameidata *ndp, struct proc *p)
{
struct vnode *devvp; /* vnode for blk device to mount */
struct msdosfs_args args; /* will hold data from mount request */
/* msdosfs specific mount control block */
struct msdosfsmount *pmp = NULL;
size_t size;
int error, flags;
mode_t accessmode;
char *fspec = NULL;
error = copyin(data, &args, sizeof(struct msdosfs_args));
if (error)
return (error);
/*
* If updating, check whether changing from read-only to
* read/write; if there is no device name, that's all we do.
*/
if (mp->mnt_flag & MNT_UPDATE) {
pmp = VFSTOMSDOSFS(mp);
error = 0;
if (!(pmp->pm_flags & MSDOSFSMNT_RONLY) &&
(mp->mnt_flag & MNT_RDONLY)) {
flags = WRITECLOSE;
if (mp->mnt_flag & MNT_FORCE)
flags |= FORCECLOSE;
error = vflush(mp, NULLVP, flags);
}
if (!error && (mp->mnt_flag & MNT_RELOAD))
/* not yet implemented */
error = EOPNOTSUPP;
if (error)
return (error);
if ((pmp->pm_flags & MSDOSFSMNT_RONLY) &&
(mp->mnt_flag & MNT_WANTRDWR)) {
/*
* If upgrade to read-write by non-root, then verify
* that user has necessary permissions on the device.
*/
if (suser(p, 0) != 0) {
devvp = pmp->pm_devvp;
vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, p);
error = VOP_ACCESS(devvp, VREAD | VWRITE,
p->p_ucred, p);
VOP_UNLOCK(devvp, 0, p);
if (error)
return (error);
}
pmp->pm_flags &= ~MSDOSFSMNT_RONLY;
}
if (args.fspec == 0) {
#ifdef __notyet__ /* doesn't work correctly with current mountd XXX */
if (args.flags & MSDOSFSMNT_MNTOPT) {
pmp->pm_flags &= ~MSDOSFSMNT_MNTOPT;
pmp->pm_flags |= args.flags & MSDOSFSMNT_MNTOPT;
if (pmp->pm_flags & MSDOSFSMNT_NOWIN95)
pmp->pm_flags |= MSDOSFSMNT_SHORTNAME;
}
#endif
/*
* Process export requests.
*/
return (vfs_export(mp, &pmp->pm_export,
&args.export_info));
}
}
/*
* Not an update, or updating the name: look up the name
* and verify that it refers to a sensible block device.
*/
fspec = malloc(MNAMELEN, M_MOUNT, M_WAITOK);
error = copyinstr(args.fspec, fspec, MNAMELEN - 1, &size);
if (error)
goto error;
disk_map(fspec, fspec, MNAMELEN, DM_OPENBLCK);
NDINIT(ndp, LOOKUP, FOLLOW, UIO_SYSSPACE, fspec, p);
if ((error = namei(ndp)) != 0)
goto error;
devvp = ndp->ni_vp;
if (devvp->v_type != VBLK) {
error = ENOTBLK;
goto error_devvp;
}
if (major(devvp->v_rdev) >= nblkdev) {
error = ENXIO;
goto error_devvp;
}
/*
* If mount by non-root, then verify that user has necessary
* permissions on the device.
*/
if (suser(p, 0) != 0) {
accessmode = VREAD;
if ((mp->mnt_flag & MNT_RDONLY) == 0)
accessmode |= VWRITE;
vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, p);
error = VOP_ACCESS(devvp, accessmode, p->p_ucred, p);
VOP_UNLOCK(devvp, 0, p);
if (error)
goto error_devvp;
}
if ((mp->mnt_flag & MNT_UPDATE) == 0)
error = msdosfs_mountfs(devvp, mp, p, &args);
else {
if (devvp != pmp->pm_devvp)
error = EINVAL; /* XXX needs translation */
else
vrele(devvp);
}
if (error)
goto error_devvp;
pmp = VFSTOMSDOSFS(mp);
pmp->pm_gid = args.gid;
pmp->pm_uid = args.uid;
pmp->pm_mask = args.mask;
pmp->pm_flags |= args.flags & MSDOSFSMNT_MNTOPT;
if (pmp->pm_flags & MSDOSFSMNT_NOWIN95)
pmp->pm_flags |= MSDOSFSMNT_SHORTNAME;
else if (!(pmp->pm_flags &
(MSDOSFSMNT_SHORTNAME | MSDOSFSMNT_LONGNAME))) {
struct vnode *rvp;
/*
* Try to divine whether to support Win'95 long filenames
*/
if (FAT32(pmp))
pmp->pm_flags |= MSDOSFSMNT_LONGNAME;
else {
if ((error = msdosfs_root(mp, &rvp)) != 0) {
msdosfs_unmount(mp, MNT_FORCE, p);
goto error;
}
pmp->pm_flags |= findwin95(VTODE(rvp))
? MSDOSFSMNT_LONGNAME
: MSDOSFSMNT_SHORTNAME;
vput(rvp);
}
}
(void) copyinstr(path, mp->mnt_stat.f_mntonname, MNAMELEN - 1, &size);
bzero(mp->mnt_stat.f_mntonname + size, MNAMELEN - size);
size = strlcpy(mp->mnt_stat.f_mntfromname, fspec, MNAMELEN - 1);
bzero(mp->mnt_stat.f_mntfromname + size, MNAMELEN - size);
bcopy(&args, &mp->mnt_stat.mount_info.msdosfs_args, sizeof(args));
#ifdef MSDOSFS_DEBUG
printf("msdosfs_mount(): mp %x, pmp %x, inusemap %x\n", mp,
pmp, pmp->pm_inusemap);
#endif
return (0);
error_devvp:
vrele(devvp);
error:
if (fspec)
free(fspec, M_MOUNT);
return (error);
}
/*
* When we search a directory the blocks containing directory entries are
* read and examined. The directory entries contain information that would
* normally be in the inode of a unix filesystem. This means that some of
* a directory's contents may also be in memory resident denodes (sort of
* an inode). This can cause problems if we are searching while some other
* process is modifying a directory. To prevent one process from accessing
* incompletely modified directory information we depend upon being the
* sole owner of a directory block. bread/brelse provide this service.
* This being the case, when a process modifies a directory it must first
* acquire the disk block that contains the directory entry to be modified.
* Then update the disk block and the denode, and then write the disk block
* out to disk. This way disk blocks containing directory entries and in
* memory denode's will be in synch.
*/
static int
msdosfs_lookup_(struct vnode *vdp, struct vnode **vpp,
struct componentname *cnp, u_int64_t *dd_inum)
{
struct mbnambuf nb;
daddr_t bn;
int error;
int slotcount;
int slotoffset = 0;
int frcn;
u_long cluster;
int blkoff;
int diroff;
int blsize;
int isadir; /* ~0 if found direntry is a directory */
u_long scn; /* starting cluster number */
struct vnode *pdp;
struct denode *dp;
struct denode *tdp;
struct msdosfsmount *pmp;
struct buf *bp = 0;
struct direntry *dep = NULL;
u_char dosfilename[12];
int flags = cnp->cn_flags;
int nameiop = cnp->cn_nameiop;
int unlen;
u_int64_t inode1;
int wincnt = 1;
int chksum = -1, chksum_ok;
int olddos = 1;
#ifdef MSDOSFS_DEBUG
printf("msdosfs_lookup(): looking for %s\n", cnp->cn_nameptr);
#endif
dp = VTODE(vdp);
pmp = dp->de_pmp;
#ifdef MSDOSFS_DEBUG
printf("msdosfs_lookup(): vdp %p, dp %p, Attr %02x\n",
vdp, dp, dp->de_Attributes);
#endif
restart:
if (vpp != NULL)
*vpp = NULL;
/*
* If they are going after the . or .. entry in the root directory,
* they won't find it. DOS filesystems don't have them in the root
* directory. So, we fake it. deget() is in on this scam too.
*/
if ((vdp->v_vflag & VV_ROOT) && cnp->cn_nameptr[0] == '.' &&
(cnp->cn_namelen == 1 ||
(cnp->cn_namelen == 2 && cnp->cn_nameptr[1] == '.'))) {
isadir = ATTR_DIRECTORY;
scn = MSDOSFSROOT;
#ifdef MSDOSFS_DEBUG
printf("msdosfs_lookup(): looking for . or .. in root directory\n");
#endif
cluster = MSDOSFSROOT;
blkoff = MSDOSFSROOT_OFS;
goto foundroot;
}
switch (unix2dosfn((const u_char *)cnp->cn_nameptr, dosfilename,
cnp->cn_namelen, 0, pmp)) {
case 0:
return (EINVAL);
case 1:
break;
case 2:
wincnt = winSlotCnt((const u_char *)cnp->cn_nameptr,
cnp->cn_namelen, pmp) + 1;
break;
case 3:
olddos = 0;
wincnt = winSlotCnt((const u_char *)cnp->cn_nameptr,
cnp->cn_namelen, pmp) + 1;
break;
}
if (pmp->pm_flags & MSDOSFSMNT_SHORTNAME) {
wincnt = 1;
olddos = 1;
}
unlen = winLenFixup(cnp->cn_nameptr, cnp->cn_namelen);
/*
* Suppress search for slots unless creating
* file and at end of pathname, in which case
* we watch for a place to put the new file in
* case it doesn't already exist.
*/
slotcount = wincnt;
if ((nameiop == CREATE || nameiop == RENAME) &&
(flags & ISLASTCN))
slotcount = 0;
#ifdef MSDOSFS_DEBUG
printf("msdosfs_lookup(): dos version of filename %s, length %ld\n",
dosfilename, cnp->cn_namelen);
#endif
/*
* Search the directory pointed at by vdp for the name pointed at
* by cnp->cn_nameptr.
*/
tdp = NULL;
mbnambuf_init(&nb);
/*
* The outer loop ranges over the clusters that make up the
* directory. Note that the root directory is different from all
* other directories. It has a fixed number of blocks that are not
* part of the pool of allocatable clusters. So, we treat it a
* little differently. The root directory starts at "cluster" 0.
*/
diroff = 0;
for (frcn = 0;; frcn++) {
error = pcbmap(dp, frcn, &bn, &cluster, &blsize);
if (error) {
if (error == E2BIG)
break;
return (error);
}
error = bread(pmp->pm_devvp, bn, blsize, NOCRED, &bp);
if (error) {
brelse(bp);
return (error);
}
for (blkoff = 0; blkoff < blsize;
blkoff += sizeof(struct direntry),
diroff += sizeof(struct direntry)) {
dep = (struct direntry *)(bp->b_data + blkoff);
/*
* If the slot is empty and we are still looking
* for an empty then remember this one. If the
* slot is not empty then check to see if it
* matches what we are looking for. If the slot
* has never been filled with anything, then the
* remainder of the directory has never been used,
* so there is no point in searching it.
*/
if (dep->deName[0] == SLOT_EMPTY ||
dep->deName[0] == SLOT_DELETED) {
/*
* Drop memory of previous long matches
*/
chksum = -1;
mbnambuf_init(&nb);
if (slotcount < wincnt) {
slotcount++;
slotoffset = diroff;
}
if (dep->deName[0] == SLOT_EMPTY) {
brelse(bp);
goto notfound;
}
} else {
/*
* If there wasn't enough space for our winentries,
* forget about the empty space
*/
if (slotcount < wincnt)
slotcount = 0;
/*
* Check for Win95 long filename entry
*/
if (dep->deAttributes == ATTR_WIN95) {
if (pmp->pm_flags & MSDOSFSMNT_SHORTNAME)
continue;
chksum = win2unixfn(&nb,
(struct winentry *)dep, chksum,
pmp);
continue;
}
chksum = winChkName(&nb,
(const u_char *)cnp->cn_nameptr, unlen,
chksum, pmp);
if (chksum == -2) {
chksum = -1;
continue;
}
/*
* Ignore volume labels (anywhere, not just
* the root directory).
*/
if (dep->deAttributes & ATTR_VOLUME) {
chksum = -1;
continue;
}
/*
* Check for a checksum or name match
*/
chksum_ok = (chksum == winChksum(dep->deName));
if (!chksum_ok
&& (!olddos || bcmp(dosfilename, dep->deName, 11))) {
chksum = -1;
continue;
}
#ifdef MSDOSFS_DEBUG
printf("msdosfs_lookup(): match blkoff %d, diroff %d\n",
blkoff, diroff);
#endif
/*
* Remember where this directory
* entry came from for whoever did
* this lookup.
*/
dp->de_fndoffset = diroff;
if (chksum_ok && nameiop == RENAME) {
/*
* Target had correct long name
* directory entries, reuse them
* as needed.
*/
dp->de_fndcnt = wincnt - 1;
} else {
/*
* Long name directory entries
* not present or corrupt, can only
* reuse dos directory entry.
*/
dp->de_fndcnt = 0;
}
goto found;
}
} /* for (blkoff = 0; .... */
/*
* Release the buffer holding the directory cluster just
* searched.
*/
brelse(bp);
} /* for (frcn = 0; ; frcn++) */
notfound:
/*
* We hold no disk buffers at this point.
*/
/*
* Fixup the slot description to point to the place where
* we might put the new DOS direntry (putting the Win95
* long name entries before that)
*/
if (!slotcount) {
slotcount = 1;
slotoffset = diroff;
}
if (wincnt > slotcount)
slotoffset += sizeof(struct direntry) * (wincnt - slotcount);
/*
* If we get here we didn't find the entry we were looking for. But
* that's ok if we are creating or renaming and are at the end of
* the pathname and the directory hasn't been removed.
*/
#ifdef MSDOSFS_DEBUG
printf("msdosfs_lookup(): op %d, refcnt %ld\n",
nameiop, dp->de_refcnt);
printf(" slotcount %d, slotoffset %d\n",
slotcount, slotoffset);
#endif
if ((nameiop == CREATE || nameiop == RENAME) &&
(flags & ISLASTCN) && dp->de_refcnt != 0) {
/*
* Access for write is interpreted as allowing
* creation of files in the directory.
*/
error = VOP_ACCESS(vdp, VWRITE, cnp->cn_cred, cnp->cn_thread);
if (error)
return (error);
/*
* Return an indication of where the new directory
* entry should be put.
*/
dp->de_fndoffset = slotoffset;
dp->de_fndcnt = wincnt - 1;
/*
* We return with the directory locked, so that
* the parameters we set up above will still be
* valid if we actually decide to do a direnter().
* We return ni_vp == NULL to indicate that the entry
* does not currently exist; we leave a pointer to
* the (locked) directory inode in ndp->ni_dvp.
* The pathname buffer is saved so that the name
* can be obtained later.
*
* NB - if the directory is unlocked, then this
* information cannot be used.
*/
cnp->cn_flags |= SAVENAME;
return (EJUSTRETURN);
}
#if 0
/*
* Insert name into cache (as non-existent) if appropriate.
*
* XXX Negative caching is broken for msdosfs because the name
* cache doesn't understand peculiarities such as case insensitivity
* and 8.3 filenames. Hence, it may not invalidate all negative
* entries if a file with this name is later created.
*/
if ((cnp->cn_flags & MAKEENTRY) && nameiop != CREATE)
cache_enter(vdp, *vpp, cnp);
#endif
return (ENOENT);
found:
/*
* NOTE: We still have the buffer with matched directory entry at
* this point.
*/
isadir = dep->deAttributes & ATTR_DIRECTORY;
scn = getushort(dep->deStartCluster);
if (FAT32(pmp)) {
scn |= getushort(dep->deHighClust) << 16;
if (scn == pmp->pm_rootdirblk) {
/*
* There should actually be 0 here.
* Just ignore the error.
*/
scn = MSDOSFSROOT;
}
}
if (isadir) {
cluster = scn;
if (cluster == MSDOSFSROOT)
blkoff = MSDOSFSROOT_OFS;
else
blkoff = 0;
} else if (cluster == MSDOSFSROOT)
blkoff = diroff;
/*
* Now release buf to allow deget to read the entry again.
* Reserving it here and giving it to deget could result
* in a deadlock.
*/
brelse(bp);
bp = 0;
foundroot:
/*
* If we entered at foundroot, then we are looking for the . or ..
* entry of the filesystems root directory. isadir and scn were
* setup before jumping here. And, bp is already null.
*/
if (FAT32(pmp) && scn == MSDOSFSROOT)
scn = pmp->pm_rootdirblk;
if (dd_inum != NULL) {
*dd_inum = (uint64_t)pmp->pm_bpcluster * scn + blkoff;
return (0);
}
/*
* If deleting, and at end of pathname, return
* parameters which can be used to remove file.
*/
if (nameiop == DELETE && (flags & ISLASTCN)) {
/*
* Don't allow deleting the root.
*/
if (blkoff == MSDOSFSROOT_OFS)
return (EBUSY);
/*
* Write access to directory required to delete files.
*/
error = VOP_ACCESS(vdp, VWRITE, cnp->cn_cred, cnp->cn_thread);
if (error)
return (error);
/*
* Return pointer to current entry in dp->i_offset.
* Save directory inode pointer in ndp->ni_dvp for dirremove().
*/
if (dp->de_StartCluster == scn && isadir) { /* "." */
VREF(vdp);
*vpp = vdp;
return (0);
}
error = deget(pmp, cluster, blkoff, &tdp);
if (error)
return (error);
*vpp = DETOV(tdp);
return (0);
}
/*
* If rewriting (RENAME), return the inode and the
* information required to rewrite the present directory
* Must get inode of directory entry to verify it's a
* regular file, or empty directory.
*/
if (nameiop == RENAME && (flags & ISLASTCN)) {
if (blkoff == MSDOSFSROOT_OFS)
return (EBUSY);
error = VOP_ACCESS(vdp, VWRITE, cnp->cn_cred, cnp->cn_thread);
if (error)
return (error);
/*
* Careful about locking second inode.
* This can only occur if the target is ".".
*/
if (dp->de_StartCluster == scn && isadir)
return (EISDIR);
if ((error = deget(pmp, cluster, blkoff, &tdp)) != 0)
return (error);
*vpp = DETOV(tdp);
cnp->cn_flags |= SAVENAME;
return (0);
}
/*
* Step through the translation in the name. We do not `vput' the
* directory because we may need it again if a symbolic link
* is relative to the current directory. Instead we save it
* unlocked as "pdp". We must get the target inode before unlocking
* the directory to insure that the inode will not be removed
* before we get it. We prevent deadlock by always fetching
* inodes from the root, moving down the directory tree. Thus
* when following backward pointers ".." we must unlock the
* parent directory before getting the requested directory.
*/
pdp = vdp;
if (flags & ISDOTDOT) {
error = msdosfs_deget_dotdot(pdp, cluster, blkoff, vpp);
if (error) {
*vpp = NULL;
return (error);
}
/*
* Recheck that ".." still points to the inode we
* looked up before pdp lock was dropped.
*/
error = msdosfs_lookup_(pdp, NULL, cnp, &inode1);
if (error) {
vput(*vpp);
*vpp = NULL;
return (error);
}
if (VTODE(*vpp)->de_inode != inode1) {
vput(*vpp);
goto restart;
}
} else if (dp->de_StartCluster == scn && isadir) {
VREF(vdp); /* we want ourself, ie "." */
*vpp = vdp;
} else {
if ((error = deget(pmp, cluster, blkoff, &tdp)) != 0)
return (error);
*vpp = DETOV(tdp);
}
/*
* Insert name into cache if appropriate.
*/
if (cnp->cn_flags & MAKEENTRY)
cache_enter(vdp, *vpp, cnp);
return (0);
}
/*
* If deget() succeeds it returns with the gotten denode locked().
*
* pmp - address of msdosfsmount structure of the filesystem containing
* the denode of interest. The address of
* the msdosfsmount structure are used.
* dirclust - which cluster bp contains, if dirclust is 0 (root directory)
* diroffset is relative to the beginning of the root directory,
* otherwise it is cluster relative.
* diroffset - offset past begin of cluster of denode we want
* depp - returns the address of the gotten denode.
*/
int
deget(struct msdosfsmount *pmp, u_long dirclust, u_long diroffset,
struct denode **depp)
{
int error;
uint64_t inode;
struct mount *mntp = pmp->pm_mountp;
struct direntry *direntptr;
struct denode *ldep;
struct vnode *nvp, *xvp;
struct buf *bp;
#ifdef MSDOSFS_DEBUG
printf("deget(pmp %p, dirclust %lu, diroffset %lx, depp %p)\n",
pmp, dirclust, diroffset, depp);
#endif
/*
* On FAT32 filesystems, root is a (more or less) normal
* directory
*/
if (FAT32(pmp) && dirclust == MSDOSFSROOT)
dirclust = pmp->pm_rootdirblk;
/*
* See if the denode is in the denode cache. Use the location of
* the directory entry to compute the hash value. For subdir use
* address of "." entry. For root dir (if not FAT32) use cluster
* MSDOSFSROOT, offset MSDOSFSROOT_OFS
*
* NOTE: The check for de_refcnt > 0 below insures the denode being
* examined does not represent an unlinked but still open file.
* These files are not to be accessible even when the directory
* entry that represented the file happens to be reused while the
* deleted file is still open.
*/
inode = (uint64_t)pmp->pm_bpcluster * dirclust + diroffset;
error = vfs_hash_get(mntp, inode, LK_EXCLUSIVE, curthread, &nvp,
de_vncmpf, &inode);
if (error)
return (error);
if (nvp != NULL) {
*depp = VTODE(nvp);
KASSERT((*depp)->de_dirclust == dirclust, ("wrong dirclust"));
KASSERT((*depp)->de_diroffset == diroffset, ("wrong diroffset"));
return (0);
}
ldep = malloc(sizeof(struct denode), M_MSDOSFSNODE, M_WAITOK | M_ZERO);
/*
* Directory entry was not in cache, have to create a vnode and
* copy it from the passed disk buffer.
*/
/* getnewvnode() does a VREF() on the vnode */
error = getnewvnode("msdosfs", mntp, &msdosfs_vnodeops, &nvp);
if (error) {
*depp = NULL;
free(ldep, M_MSDOSFSNODE);
return error;
}
nvp->v_data = ldep;
ldep->de_vnode = nvp;
ldep->de_flag = 0;
ldep->de_dirclust = dirclust;
ldep->de_diroffset = diroffset;
ldep->de_inode = inode;
lockmgr(nvp->v_vnlock, LK_EXCLUSIVE, NULL);
fc_purge(ldep, 0); /* init the fat cache for this denode */
error = insmntque(nvp, mntp);
if (error != 0) {
free(ldep, M_MSDOSFSNODE);
*depp = NULL;
return (error);
}
error = vfs_hash_insert(nvp, inode, LK_EXCLUSIVE, curthread, &xvp,
de_vncmpf, &inode);
if (error) {
*depp = NULL;
return (error);
}
if (xvp != NULL) {
*depp = xvp->v_data;
return (0);
}
ldep->de_pmp = pmp;
ldep->de_refcnt = 1;
/*
* Copy the directory entry into the denode area of the vnode.
*/
if ((dirclust == MSDOSFSROOT
|| (FAT32(pmp) && dirclust == pmp->pm_rootdirblk))
&& diroffset == MSDOSFSROOT_OFS) {
/*
* Directory entry for the root directory. There isn't one,
* so we manufacture one. We should probably rummage
* through the root directory and find a label entry (if it
* exists), and then use the time and date from that entry
* as the time and date for the root denode.
*/
nvp->v_vflag |= VV_ROOT; /* should be further down XXX */
ldep->de_Attributes = ATTR_DIRECTORY;
ldep->de_LowerCase = 0;
if (FAT32(pmp))
ldep->de_StartCluster = pmp->pm_rootdirblk;
/* de_FileSize will be filled in further down */
else {
ldep->de_StartCluster = MSDOSFSROOT;
ldep->de_FileSize = pmp->pm_rootdirsize * DEV_BSIZE;
}
/*
* fill in time and date so that fattime2timespec() doesn't
* spit up when called from msdosfs_getattr() with root
* denode
*/
ldep->de_CHun = 0;
ldep->de_CTime = 0x0000; /* 00:00:00 */
ldep->de_CDate = (0 << DD_YEAR_SHIFT) | (1 << DD_MONTH_SHIFT)
| (1 << DD_DAY_SHIFT);
/* Jan 1, 1980 */
ldep->de_ADate = ldep->de_CDate;
ldep->de_MTime = ldep->de_CTime;
ldep->de_MDate = ldep->de_CDate;
/* leave the other fields as garbage */
} else {
error = readep(pmp, dirclust, diroffset, &bp, &direntptr);
if (error) {
/*
* The denode does not contain anything useful, so
* it would be wrong to leave it on its hash chain.
* Arrange for vput() to just forget about it.
*/
ldep->de_Name[0] = SLOT_DELETED;
vput(nvp);
*depp = NULL;
return (error);
}
(void)DE_INTERNALIZE(ldep, direntptr);
brelse(bp);
}
/*
* Fill in a few fields of the vnode and finish filling in the
* denode. Then return the address of the found denode.
*/
if (ldep->de_Attributes & ATTR_DIRECTORY) {
/*
* Since DOS directory entries that describe directories
* have 0 in the filesize field, we take this opportunity
* to find out the length of the directory and plug it into
* the denode structure.
*/
u_long size;
/*
* XXX it sometimes happens that the "." entry has cluster
* number 0 when it shouldn't. Use the actual cluster number
* instead of what is written in directory entry.
*/
if (diroffset == 0 && ldep->de_StartCluster != dirclust) {
#ifdef MSDOSFS_DEBUG
printf("deget(): \".\" entry at clust %lu != %lu\n",
dirclust, ldep->de_StartCluster);
#endif
ldep->de_StartCluster = dirclust;
}
nvp->v_type = VDIR;
if (ldep->de_StartCluster != MSDOSFSROOT) {
error = pcbmap(ldep, 0xffff, 0, &size, 0);
if (error == E2BIG) {
ldep->de_FileSize = de_cn2off(pmp, size);
error = 0;
} else {
#ifdef MSDOSFS_DEBUG
printf("deget(): pcbmap returned %d\n", error);
#endif
}
}
} else
nvp->v_type = VREG;
ldep->de_modrev = init_va_filerev();
*depp = ldep;
return (0);
}
struct msdosfsmount *
msdosfs_mount(struct vnode *devvp, int flags)
{
struct msdosfsmount *pmp = NULL;
struct buf *bp;
union bootsector *bsp;
struct byte_bpb33 *b33;
struct byte_bpb50 *b50;
struct byte_bpb710 *b710;
uint8_t SecPerClust;
int ronly = 0, error, tmp;
int bsize;
struct msdos_options *m = devvp->fs->fs_specific;
uint64_t psize = m->create_size;
unsigned secsize = 512;
DPRINTF(("%s(bread 0)\n", __func__));
if ((error = bread(devvp, 0, secsize, NULL, 0, &bp)) != 0)
goto error_exit;
bsp = (union bootsector *)bp->b_data;
b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB;
b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB;
b710 = (struct byte_bpb710 *)bsp->bs710.bsBPB;
if (!(flags & MSDOSFSMNT_GEMDOSFS)) {
if (bsp->bs50.bsBootSectSig0 != BOOTSIG0
|| bsp->bs50.bsBootSectSig1 != BOOTSIG1) {
DPRINTF(("bootsig0 %d bootsig1 %d\n",
bsp->bs50.bsBootSectSig0,
bsp->bs50.bsBootSectSig1));
error = EINVAL;
goto error_exit;
}
bsize = 0;
} else
bsize = 512;
pmp = ecalloc(1, sizeof *pmp);
/*
* Compute several useful quantities from the bpb in the
* bootsector. Copy in the dos 5 variant of the bpb then fix up
* the fields that are different between dos 5 and dos 3.3.
*/
SecPerClust = b50->bpbSecPerClust;
pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec);
pmp->pm_ResSectors = getushort(b50->bpbResSectors);
pmp->pm_FATs = b50->bpbFATs;
pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts);
pmp->pm_Sectors = getushort(b50->bpbSectors);
pmp->pm_FATsecs = getushort(b50->bpbFATsecs);
pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack);
pmp->pm_Heads = getushort(b50->bpbHeads);
pmp->pm_Media = b50->bpbMedia;
DPRINTF(("%s(BytesPerSec=%u, ResSectors=%u, FATs=%d, RootDirEnts=%u, "
"Sectors=%u, FATsecs=%lu, SecPerTrack=%u, Heads=%u, Media=%u)\n",
__func__, pmp->pm_BytesPerSec, pmp->pm_ResSectors, pmp->pm_FATs,
pmp->pm_RootDirEnts, pmp->pm_Sectors, pmp->pm_FATsecs,
pmp->pm_SecPerTrack, pmp->pm_Heads, pmp->pm_Media));
if (!(flags & MSDOSFSMNT_GEMDOSFS)) {
/* XXX - We should probably check more values here */
if (!pmp->pm_BytesPerSec || !SecPerClust
|| pmp->pm_SecPerTrack > 63) {
DPRINTF(("bytespersec %d secperclust %d "
"secpertrack %d\n",
pmp->pm_BytesPerSec, SecPerClust,
pmp->pm_SecPerTrack));
error = EINVAL;
goto error_exit;
}
}
if (pmp->pm_Sectors == 0) {
pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs);
pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors);
} else {
pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs);
pmp->pm_HugeSectors = pmp->pm_Sectors;
}
if (pmp->pm_RootDirEnts == 0) {
unsigned short vers = getushort(b710->bpbFSVers);
/*
* Some say that bsBootSectSig[23] must be zero, but
* Windows does not require this and some digital cameras
* do not set these to zero. Therefore, do not insist.
*/
if (pmp->pm_Sectors || pmp->pm_FATsecs || vers) {
DPRINTF(("sectors %d fatsecs %lu vers %d\n",
pmp->pm_Sectors, pmp->pm_FATsecs, vers));
error = EINVAL;
goto error_exit;
}
pmp->pm_fatmask = FAT32_MASK;
pmp->pm_fatmult = 4;
pmp->pm_fatdiv = 1;
pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs);
/* mirrorring is enabled if the FATMIRROR bit is not set */
if ((getushort(b710->bpbExtFlags) & FATMIRROR) == 0)
pmp->pm_flags |= MSDOSFS_FATMIRROR;
else
pmp->pm_curfat = getushort(b710->bpbExtFlags) & FATNUM;
} else
pmp->pm_flags |= MSDOSFS_FATMIRROR;
if (flags & MSDOSFSMNT_GEMDOSFS) {
if (FAT32(pmp)) {
DPRINTF(("FAT32 for GEMDOS\n"));
/*
* GEMDOS doesn't know FAT32.
*/
error = EINVAL;
goto error_exit;
}
/*
* Check a few values (could do some more):
* - logical sector size: power of 2, >= block size
* - sectors per cluster: power of 2, >= 1
* - number of sectors: >= 1, <= size of partition
*/
if ( (SecPerClust == 0)
|| (SecPerClust & (SecPerClust - 1))
|| (pmp->pm_BytesPerSec < bsize)
|| (pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1))
|| (pmp->pm_HugeSectors == 0)
|| (pmp->pm_HugeSectors * (pmp->pm_BytesPerSec / bsize)
> psize)) {
DPRINTF(("consistency checks for GEMDOS\n"));
error = EINVAL;
goto error_exit;
}
/*
* XXX - Many parts of the msdosfs driver seem to assume that
* the number of bytes per logical sector (BytesPerSec) will
* always be the same as the number of bytes per disk block
* Let's pretend it is.
*/
tmp = pmp->pm_BytesPerSec / bsize;
pmp->pm_BytesPerSec = bsize;
pmp->pm_HugeSectors *= tmp;
pmp->pm_HiddenSects *= tmp;
pmp->pm_ResSectors *= tmp;
pmp->pm_Sectors *= tmp;
pmp->pm_FATsecs *= tmp;
SecPerClust *= tmp;
}
/* Check that fs has nonzero FAT size */
if (pmp->pm_FATsecs == 0) {
DPRINTF(("FATsecs is 0\n"));
error = EINVAL;
goto error_exit;
}
pmp->pm_fatblk = pmp->pm_ResSectors;
if (FAT32(pmp)) {
pmp->pm_rootdirblk = getulong(b710->bpbRootClust);
pmp->pm_firstcluster = pmp->pm_fatblk
+ (pmp->pm_FATs * pmp->pm_FATsecs);
pmp->pm_fsinfo = getushort(b710->bpbFSInfo);
} else {
pmp->pm_rootdirblk = pmp->pm_fatblk +
(pmp->pm_FATs * pmp->pm_FATsecs);
pmp->pm_rootdirsize = (pmp->pm_RootDirEnts * sizeof(struct direntry)
+ pmp->pm_BytesPerSec - 1)
/ pmp->pm_BytesPerSec;/* in sectors */
pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize;
}
pmp->pm_nmbrofclusters = (pmp->pm_HugeSectors - pmp->pm_firstcluster) /
SecPerClust;
pmp->pm_maxcluster = pmp->pm_nmbrofclusters + 1;
pmp->pm_fatsize = pmp->pm_FATsecs * pmp->pm_BytesPerSec;
if (flags & MSDOSFSMNT_GEMDOSFS) {
if (pmp->pm_nmbrofclusters <= (0xff0 - 2)) {
pmp->pm_fatmask = FAT12_MASK;
pmp->pm_fatmult = 3;
pmp->pm_fatdiv = 2;
} else {
pmp->pm_fatmask = FAT16_MASK;
pmp->pm_fatmult = 2;
pmp->pm_fatdiv = 1;
}
} else if (pmp->pm_fatmask == 0) {
if (pmp->pm_maxcluster
<= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) {
/*
* This will usually be a floppy disk. This size makes
* sure that one FAT entry will not be split across
* multiple blocks.
*/
pmp->pm_fatmask = FAT12_MASK;
pmp->pm_fatmult = 3;
pmp->pm_fatdiv = 2;
} else {
pmp->pm_fatmask = FAT16_MASK;
pmp->pm_fatmult = 2;
pmp->pm_fatdiv = 1;
}
}
if (FAT12(pmp))
pmp->pm_fatblocksize = 3 * pmp->pm_BytesPerSec;
else
pmp->pm_fatblocksize = MAXBSIZE;
pmp->pm_fatblocksec = pmp->pm_fatblocksize / pmp->pm_BytesPerSec;
pmp->pm_bnshift = ffs(pmp->pm_BytesPerSec) - 1;
/*
* Compute mask and shift value for isolating cluster relative byte
* offsets and cluster numbers from a file offset.
*/
pmp->pm_bpcluster = SecPerClust * pmp->pm_BytesPerSec;
pmp->pm_crbomask = pmp->pm_bpcluster - 1;
pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1;
DPRINTF(("%s(fatmask=%lu, fatmult=%u, fatdiv=%u, fatblocksize=%lu, "
"fatblocksec=%lu, bnshift=%lu, pbcluster=%lu, crbomask=%lu, "
"cnshift=%lu)\n",
__func__, pmp->pm_fatmask, pmp->pm_fatmult, pmp->pm_fatdiv,
pmp->pm_fatblocksize, pmp->pm_fatblocksec, pmp->pm_bnshift,
pmp->pm_bpcluster, pmp->pm_crbomask, pmp->pm_cnshift));
/*
* Check for valid cluster size
* must be a power of 2
*/
if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) {
DPRINTF(("bpcluster %lu cnshift %lu\n",
pmp->pm_bpcluster, pmp->pm_cnshift));
error = EINVAL;
goto error_exit;
}
/*
* Release the bootsector buffer.
*/
brelse(bp, BC_AGE);
bp = NULL;
/*
* Check FSInfo.
*/
if (pmp->pm_fsinfo) {
struct fsinfo *fp;
/*
* XXX If the fsinfo block is stored on media with
* 2KB or larger sectors, is the fsinfo structure
* padded at the end or in the middle?
*/
DPRINTF(("%s(bread %lu)\n", __func__,
(unsigned long)de_bn2kb(pmp, pmp->pm_fsinfo)));
if ((error = bread(devvp, de_bn2kb(pmp, pmp->pm_fsinfo),
pmp->pm_BytesPerSec, NULL, 0, &bp)) != 0)
goto error_exit;
fp = (struct fsinfo *)bp->b_data;
if (!memcmp(fp->fsisig1, "RRaA", 4)
&& !memcmp(fp->fsisig2, "rrAa", 4)
&& !memcmp(fp->fsisig3, "\0\0\125\252", 4)
&& !memcmp(fp->fsisig4, "\0\0\125\252", 4))
pmp->pm_nxtfree = getulong(fp->fsinxtfree);
else
pmp->pm_fsinfo = 0;
brelse(bp, 0);
bp = NULL;
}
/*
* Check and validate (or perhaps invalidate?) the fsinfo structure?
* XXX
*/
if (pmp->pm_fsinfo) {
if ((pmp->pm_nxtfree == 0xffffffffUL) ||
(pmp->pm_nxtfree > pmp->pm_maxcluster))
pmp->pm_fsinfo = 0;
}
/*
* Allocate memory for the bitmap of allocated clusters, and then
* fill it in.
*/
pmp->pm_inusemap = ecalloc(sizeof(*pmp->pm_inusemap),
((pmp->pm_maxcluster + N_INUSEBITS) / N_INUSEBITS));
/*
* fillinusemap() needs pm_devvp.
*/
pmp->pm_dev = 0;
pmp->pm_devvp = devvp;
/*
* Have the inuse map filled in.
*/
if ((error = fillinusemap(pmp)) != 0) {
DPRINTF(("fillinusemap %d\n", error));
goto error_exit;
}
/*
* Finish up.
*/
if (ronly)
pmp->pm_flags |= MSDOSFSMNT_RONLY;
else
pmp->pm_fmod = 1;
/*
* If we ever do quotas for DOS filesystems this would be a place
* to fill in the info in the msdosfsmount structure. You dolt,
* quotas on dos filesystems make no sense because files have no
* owners on dos filesystems. of course there is some empty space
* in the directory entry where we could put uid's and gid's.
*/
return pmp;
error_exit:
if (bp)
brelse(bp, BC_AGE);
if (pmp) {
if (pmp->pm_inusemap)
free(pmp->pm_inusemap);
free(pmp);
}
errno = error;
return pmp;
}
