/*
* Return buffer with the contents of block "offset" from the beginning of
* directory "ip". If "res" is non-zero, fill it in with a pointer to the
* remaining space in the directory.
*/
int
cd9660_blkatoff(struct vnode *vp, off_t offset, char **res, struct buf **bpp)
{
struct iso_node *ip;
struct iso_mnt *imp;
struct buf *bp;
daddr_t lbn;
int bsize, error;
ip = VTOI(vp);
imp = ip->i_mnt;
lbn = cd9660_lblkno(imp, offset);
bsize = cd9660_blksize(imp, ip, lbn);
if ((error = bread(vp, lbn, bsize, NOCRED, 0, &bp)) != 0) {
*bpp = NULL;
return (error);
}
if (res)
*res = (char *)bp->b_data + cd9660_blkoff(imp, offset);
*bpp = bp;
return (0);
}
/*
* Vnode op for reading.
*/
int
cd9660_read(void *v)
{
struct vop_read_args /* {
struct vnode *a_vp;
struct uio *a_uio;
int a_ioflag;
kauth_cred_t a_cred;
} */ *ap = v;
struct vnode *vp = ap->a_vp;
struct uio *uio = ap->a_uio;
struct iso_node *ip = VTOI(vp);
struct iso_mnt *imp;
struct buf *bp;
daddr_t lbn, rablock;
off_t diff;
int rasize, error = 0;
long size, n, on;
if (uio->uio_resid == 0)
return (0);
if (uio->uio_offset < 0)
return (EINVAL);
if (uio->uio_offset >= ip->i_size)
return 0;
ip->i_flag |= IN_ACCESS;
imp = ip->i_mnt;
if (vp->v_type == VREG) {
const int advice = IO_ADV_DECODE(ap->a_ioflag);
error = 0;
while (uio->uio_resid > 0) {
vsize_t bytelen = MIN(ip->i_size - uio->uio_offset,
uio->uio_resid);
if (bytelen == 0)
break;
error = ubc_uiomove(&vp->v_uobj, uio, bytelen, advice,
UBC_READ | UBC_PARTIALOK | UBC_UNMAP_FLAG(vp));
if (error)
break;
}
goto out;
}
do {
lbn = cd9660_lblkno(imp, uio->uio_offset);
on = cd9660_blkoff(imp, uio->uio_offset);
n = MIN(imp->logical_block_size - on, uio->uio_resid);
diff = (off_t)ip->i_size - uio->uio_offset;
if (diff <= 0)
return (0);
if (diff < n)
n = diff;
size = cd9660_blksize(imp, ip, lbn);
rablock = lbn + 1;
if (cd9660_lblktosize(imp, rablock) < ip->i_size) {
rasize = cd9660_blksize(imp, ip, rablock);
error = breadn(vp, lbn, size, &rablock,
&rasize, 1, NOCRED, 0, &bp);
} else {
error = bread(vp, lbn, size, NOCRED, 0, &bp);
}
if (error) {
return (error);
}
n = MIN(n, size - bp->b_resid);
error = uiomove((char *)bp->b_data + on, (int)n, uio);
brelse(bp, 0);
} while (error == 0 && uio->uio_resid > 0 && n != 0);
out:
return (error);
}
/*
* Convert a component of a pathname into a pointer to a locked inode.
* This is a very central and rather complicated routine.
* If the file system is not maintained in a strict tree hierarchy,
* this can result in a deadlock situation (see comments in code below).
*
* The flag argument is LOOKUP, CREATE, RENAME, or DELETE depending on
* whether the name is to be looked up, created, renamed, or deleted.
* When CREATE, RENAME, or DELETE is specified, information usable in
* creating, renaming, or deleting a directory entry may be calculated.
* If the target of the pathname exists, lookup returns both the target
* and its parent directory locked.
* When creating or renaming, the target may * not be ".".
* When deleting , the target may be "."., but the caller must check
* to ensure it does an vrele and vput instead of two vputs.
*
* Overall outline of ufs_lookup:
*
* check accessibility of directory
* look for name in cache, if found, then if at end of path
* and deleting or creating, drop it, else return name
* search for name in directory, to found or notfound
* notfound:
* if creating, return locked directory, leaving info on available slots
* else return error
* found:
* if at end of path and deleting, return information to allow delete
* if at end of path and rewriting (RENAME), lock target
* inode and return info to allow rewrite
* if not at end, add name to cache; if at end and neither creating
* nor deleting, add name to cache
*/
int
cd9660_lookup(void *v)
{
struct vop_lookup_args /* {
struct vnode *a_dvp;
struct vnode **a_vpp;
struct componentname *a_cnp;
} */ *ap = v;
struct vnode *vdp; /* vnode for directory being searched */
struct iso_node *dp; /* inode for directory being searched */
struct iso_mnt *imp; /* file system that directory is in */
struct buf *bp; /* a buffer of directory entries */
struct iso_directory_record *ep = NULL;
/* the current directory entry */
int entryoffsetinblock; /* offset of ep in bp's buffer */
int saveoffset = -1; /* offset of last directory entry in dir */
int numdirpasses; /* strategy for directory search */
doff_t endsearch; /* offset to end directory search */
struct vnode *pdp; /* saved dp during symlink work */
struct vnode *tdp; /* returned by cd9660_vget_internal */
u_long bmask; /* block offset mask */
int error;
ino_t ino = 0;
int reclen;
u_short namelen;
char altname[ISO_MAXNAMLEN];
int res;
int assoc, len;
const char *name;
struct vnode **vpp = ap->a_vpp;
struct componentname *cnp = ap->a_cnp;
kauth_cred_t cred = cnp->cn_cred;
int flags;
int nameiop = cnp->cn_nameiop;
flags = cnp->cn_flags;
bp = NULL;
*vpp = NULL;
vdp = ap->a_dvp;
dp = VTOI(vdp);
imp = dp->i_mnt;
/*
* Check accessiblity of directory.
*/
if ((error = VOP_ACCESS(vdp, VEXEC, 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;
}
len = cnp->cn_namelen;
name = cnp->cn_nameptr;
/*
* A leading `=' means, we are looking for an associated file
*/
assoc = (imp->iso_ftype != ISO_FTYPE_RRIP && *name == ASSOCCHAR);
if (assoc) {
len--;
name++;
}
/*
* If there is cached information on a previous search of
* this directory, pick up where we last left off.
* We cache only lookups as these are the most common
* and have the greatest payoff. Caching CREATE has little
* benefit as it usually must search the entire directory
* to determine that the entry does not exist. Caching the
* location of the last DELETE or RENAME has not reduced
* profiling time and hence has been removed in the interest
* of simplicity.
*/
bmask = imp->im_bmask;
if (nameiop != LOOKUP || dp->i_diroff == 0 ||
dp->i_diroff > dp->i_size) {
entryoffsetinblock = 0;
dp->i_offset = 0;
numdirpasses = 1;
} else {
dp->i_offset = dp->i_diroff;
if ((entryoffsetinblock = dp->i_offset & bmask) &&
(error = cd9660_blkatoff(vdp, (off_t)dp->i_offset, NULL,
&bp)))
return (error);
numdirpasses = 2;
iso_nchstats.ncs_2passes++;
}
endsearch = dp->i_size;
searchloop:
while (dp->i_offset < endsearch) {
/*
* If offset is on a block boundary,
* read the next directory block.
* Release previous if it exists.
*/
if ((dp->i_offset & bmask) == 0) {
if (bp != NULL)
brelse(bp, 0);
error = cd9660_blkatoff(vdp, (off_t)dp->i_offset,
NULL, &bp);
if (error)
return (error);
entryoffsetinblock = 0;
}
/*
* Get pointer to next entry.
*/
KASSERT(bp != NULL);
ep = (struct iso_directory_record *)
((char *)bp->b_data + entryoffsetinblock);
reclen = isonum_711(ep->length);
if (reclen == 0) {
/* skip to next block, if any */
dp->i_offset =
(dp->i_offset & ~bmask) + imp->logical_block_size;
continue;
}
if (reclen < ISO_DIRECTORY_RECORD_SIZE)
/* illegal entry, stop */
break;
if (entryoffsetinblock + reclen > imp->logical_block_size)
/* entries are not allowed to cross boundaries */
break;
namelen = isonum_711(ep->name_len);
if (reclen < ISO_DIRECTORY_RECORD_SIZE + namelen)
/* illegal entry, stop */
break;
/*
* Check for a name match.
*/
switch (imp->iso_ftype) {
default:
if ((!(isonum_711(ep->flags)&4)) == !assoc) {
if ((len == 1
&& *name == '.')
|| (flags & ISDOTDOT)) {
if (namelen == 1
&& ep->name[0] == ((flags & ISDOTDOT) ? 1 : 0)) {
/*
* Save directory entry's inode number and
* release directory buffer.
*/
dp->i_ino = isodirino(ep, imp);
goto found;
}
if (namelen != 1
|| ep->name[0] != 0)
goto notfound;
} else if (!(res = isofncmp(name,len,
ep->name,namelen,
imp->im_joliet_level))) {
if (isonum_711(ep->flags)&2)
ino = isodirino(ep, imp);
else
ino = dbtob(bp->b_blkno)
+ entryoffsetinblock;
saveoffset = dp->i_offset;
} else if (ino)
goto foundino;
#ifdef NOSORTBUG /* On some CDs directory entries are not sorted correctly */
else if (res < 0)
goto notfound;
else if (res > 0 && numdirpasses == 2)
numdirpasses++;
#endif
}
break;
case ISO_FTYPE_RRIP:
if (isonum_711(ep->flags)&2)
ino = isodirino(ep, imp);
else
ino = dbtob(bp->b_blkno) + entryoffsetinblock;
dp->i_ino = ino;
cd9660_rrip_getname(ep,altname,&namelen,&dp->i_ino,imp);
if (namelen == cnp->cn_namelen) {
if (imp->im_flags & ISOFSMNT_RRCASEINS) {
if (strncasecmp(name, altname, namelen) == 0)
goto found;
} else {
if (memcmp(name, altname, namelen) == 0)
goto found;
}
}
ino = 0;
break;
}
dp->i_offset += reclen;
entryoffsetinblock += reclen;
}
if (ino) {
foundino:
dp->i_ino = ino;
if (saveoffset != dp->i_offset) {
if (cd9660_lblkno(imp, dp->i_offset) !=
cd9660_lblkno(imp, saveoffset)) {
if (bp != NULL)
brelse(bp, 0);
if ((error = cd9660_blkatoff(vdp,
(off_t)saveoffset, NULL, &bp)) != 0)
return (error);
}
entryoffsetinblock = saveoffset & bmask;
ep = (struct iso_directory_record *)
((char *)bp->b_data + entryoffsetinblock);
dp->i_offset = saveoffset;
}
goto found;
}
notfound:
/*
* If we started in the middle of the directory and failed
* to find our target, we must check the beginning as well.
*/
if (numdirpasses == 2) {
numdirpasses--;
dp->i_offset = 0;
endsearch = dp->i_diroff;
goto searchloop;
}
if (bp != NULL)
brelse(bp, 0);
/*
* Insert name into cache (as non-existent) if appropriate.
*/
cache_enter(vdp, *vpp, cnp->cn_nameptr, cnp->cn_namelen, cnp->cn_flags);
return (nameiop == CREATE || nameiop == RENAME) ? EROFS : ENOENT;
found:
if (numdirpasses == 2)
iso_nchstats.ncs_pass2++;
/*
* Found component in pathname.
* If the final component of path name, save information
* in the cache as to where the entry was found.
*/
if ((flags & ISLASTCN) && nameiop == LOOKUP)
dp->i_diroff = dp->i_offset;
/*
* Step through the translation in the name. We do not `iput' 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 `iget' 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 ino is different from dp->i_ino,
* it's a relocated directory.
*/
brelse(bp, 0);
if (flags & ISDOTDOT) {
VOP_UNLOCK(pdp); /* race to get the inode */
error = cd9660_vget_internal(vdp->v_mount, dp->i_ino, &tdp,
dp->i_ino != ino, ep);
vn_lock(pdp, LK_EXCLUSIVE | LK_RETRY);
if (error)
return error;
*vpp = tdp;
} else if (dp->i_number == dp->i_ino) {
vref(vdp); /* we want ourself, ie "." */
*vpp = vdp;
} else {
error = cd9660_vget_internal(vdp->v_mount, dp->i_ino, &tdp,
dp->i_ino != ino, ep);
if (error)
return (error);
*vpp = tdp;
}
/*
* Insert name into cache if appropriate.
*/
cache_enter(vdp, *vpp, cnp->cn_nameptr, cnp->cn_namelen, cnp->cn_flags);
return 0;
}
int
cd9660_vget_internal(struct mount *mp, ino_t ino, struct vnode **vpp,
int relocated, struct iso_directory_record *isodir)
{
struct iso_mnt *imp;
struct iso_node *ip;
struct buf *bp;
struct vnode *vp;
dev_t dev;
int error;
imp = VFSTOISOFS(mp);
dev = imp->im_dev;
retry:
if ((*vpp = cd9660_ihashget(dev, ino, LK_EXCLUSIVE)) != NULLVP)
return (0);
/* Allocate a new vnode/iso_node. */
error = getnewvnode(VT_ISOFS, mp, cd9660_vnodeop_p, NULL, &vp);
if (error) {
*vpp = NULLVP;
return (error);
}
ip = pool_get(&cd9660_node_pool, PR_WAITOK);
/*
* If someone beat us to it, put back the freshly allocated
* vnode/inode pair and retry.
*/
mutex_enter(&cd9660_hashlock);
if (cd9660_ihashget(dev, ino, 0) != NULL) {
mutex_exit(&cd9660_hashlock);
ungetnewvnode(vp);
pool_put(&cd9660_node_pool, ip);
goto retry;
}
memset(ip, 0, sizeof(struct iso_node));
vp->v_data = ip;
ip->i_vnode = vp;
ip->i_dev = dev;
ip->i_number = ino;
ip->i_mnt = imp;
ip->i_devvp = imp->im_devvp;
genfs_node_init(vp, &cd9660_genfsops);
/*
* Put it onto its hash chain and lock it so that other requests for
* this inode will block if they arrive while we are sleeping waiting
* for old data structures to be purged or for the contents of the
* disk portion of this inode to be read.
*/
cd9660_ihashins(ip);
mutex_exit(&cd9660_hashlock);
if (isodir == 0) {
int lbn, off;
lbn = cd9660_lblkno(imp, ino);
if (lbn >= imp->volume_space_size) {
vput(vp);
printf("fhtovp: lbn exceed volume space %d\n", lbn);
return (ESTALE);
}
off = cd9660_blkoff(imp, ino);
if (off + ISO_DIRECTORY_RECORD_SIZE > imp->logical_block_size) {
vput(vp);
printf("fhtovp: crosses block boundary %d\n",
off + ISO_DIRECTORY_RECORD_SIZE);
return (ESTALE);
}
error = bread(imp->im_devvp,
lbn << (imp->im_bshift - DEV_BSHIFT),
imp->logical_block_size, NOCRED, 0, &bp);
if (error) {
vput(vp);
printf("fhtovp: bread error %d\n",error);
return (error);
}
isodir = (struct iso_directory_record *)((char *)bp->b_data + off);
if (off + isonum_711(isodir->length) >
imp->logical_block_size) {
vput(vp);
if (bp != 0)
brelse(bp, 0);
printf("fhtovp: directory crosses block boundary %d[off=%d/len=%d]\n",
off +isonum_711(isodir->length), off,
isonum_711(isodir->length));
return (ESTALE);
}
#if 0
if (isonum_733(isodir->extent) +
isonum_711(isodir->ext_attr_length) != ifhp->ifid_start) {
if (bp != 0)
brelse(bp, 0);
printf("fhtovp: file start miss %d vs %d\n",
isonum_733(isodir->extent) + isonum_711(isodir->ext_attr_length),
ifhp->ifid_start);
return (ESTALE);
}
#endif
} else
bp = 0;
vref(ip->i_devvp);
if (relocated) {
/*
* On relocated directories we must
* read the `.' entry out of a dir.
*/
ip->iso_start = ino >> imp->im_bshift;
if (bp != 0)
brelse(bp, 0);
if ((error = cd9660_blkatoff(vp, (off_t)0, NULL, &bp)) != 0) {
vput(vp);
return (error);
}
isodir = (struct iso_directory_record *)bp->b_data;
}
ip->iso_extent = isonum_733(isodir->extent);
ip->i_size = isonum_733(isodir->size);
ip->iso_start = isonum_711(isodir->ext_attr_length) + ip->iso_extent;
/*
* Setup time stamp, attribute
*/
vp->v_type = VNON;
switch (imp->iso_ftype) {
default: /* ISO_FTYPE_9660 */
{
struct buf *bp2;
int off;
if ((imp->im_flags & ISOFSMNT_EXTATT)
&& (off = isonum_711(isodir->ext_attr_length)))
cd9660_blkatoff(vp, (off_t)-(off << imp->im_bshift),
NULL, &bp2);
else
bp2 = NULL;
cd9660_defattr(isodir, ip, bp2);
cd9660_deftstamp(isodir, ip, bp2);
if (bp2)
brelse(bp2, 0);
break;
}
case ISO_FTYPE_RRIP:
cd9660_rrip_analyze(isodir, ip, imp);
break;
}
if (bp != 0)
brelse(bp, 0);
/*
* Initialize the associated vnode
*/
switch (vp->v_type = IFTOVT(ip->inode.iso_mode)) {
case VFIFO:
vp->v_op = cd9660_fifoop_p;
break;
case VCHR:
case VBLK:
/*
* if device, look at device number table for translation
*/
vp->v_op = cd9660_specop_p;
spec_node_init(vp, ip->inode.iso_rdev);
break;
case VLNK:
case VNON:
case VSOCK:
case VDIR:
case VBAD:
break;
case VREG:
uvm_vnp_setsize(vp, ip->i_size);
break;
}
if (vp->v_type != VREG)
uvm_vnp_setsize(vp, 0);
if (ip->iso_extent == imp->root_extent)
vp->v_vflag |= VV_ROOT;
/*
* XXX need generation number?
*/
*vpp = vp;
return (0);
}
