/*
* Find root of lofs mount.
*/
static int
lo_root(struct vfs *vfsp, struct vnode **vpp)
{
*vpp = vtoli(vfsp)->li_rootvp;
#ifdef LODEBUG
lo_dprint(4, "lo_root(0x%p) = %p\n", vfsp, *vpp);
#endif
/*
* If the root of the filesystem is a special file, return the specvp
* version of the vnode. We don't save the specvp vnode in our
* hashtable since that's exclusively for lnodes.
*/
if (IS_DEVVP(*vpp)) {
struct vnode *svp;
svp = specvp(*vpp, (*vpp)->v_rdev, (*vpp)->v_type, kcred);
if (svp == NULL)
return (ENOSYS);
*vpp = svp;
} else {
VN_HOLD(*vpp);
}
return (0);
}
/*
* Undo loopback mount
*/
static int
lo_unmount(struct vfs *vfsp, int flag, struct cred *cr)
{
struct loinfo *li;
if (secpolicy_fs_unmount(cr, vfsp) != 0)
return (EPERM);
/*
* Forced unmount is not supported by this file system
* and thus, ENOTSUP, is being returned.
*/
if (flag & MS_FORCE)
return (ENOTSUP);
li = vtoli(vfsp);
#ifdef LODEBUG
lo_dprint(4, "lo_unmount(%p) li %p\n", vfsp, li);
#endif
if (li->li_refct != 1 || li->li_rootvp->v_count != 1) {
#ifdef LODEBUG
lo_dprint(4, "refct %d v_ct %d\n", li->li_refct,
li->li_rootvp->v_count);
#endif
return (EBUSY);
}
VN_RELE(li->li_rootvp);
return (0);
}
/*
* Free mount-specific data.
*/
static void
lo_freevfs(struct vfs *vfsp)
{
struct loinfo *li = vtoli(vfsp);
ldestroy(li);
kmem_free(li, sizeof (struct loinfo));
}
/*
* Find real vfs given loopback vfs
*/
struct vfs *
lo_realvfs(struct vfs *vfsp, struct vnode **realrootvpp)
{
struct loinfo *li = vtoli(vfsp);
struct lfsnode *lfs;
ASSERT(li->li_refct > 0);
if (vfsp == li->li_mountvfs) {
if (realrootvpp != NULL)
*realrootvpp = vtol(li->li_rootvp)->lo_vp;
return (li->li_realvfs);
}
mutex_enter(&li->li_lfslock);
for (lfs = li->li_lfs; lfs != NULL; lfs = lfs->lfs_next) {
if (vfsp == &lfs->lfs_vfs) {
if (realrootvpp != NULL)
*realrootvpp = lfs->lfs_realrootvp;
mutex_exit(&li->li_lfslock);
return (lfs->lfs_realvfs);
}
}
panic("lo_realvfs");
/*NOTREACHED*/
}
/*
* Remove a lnode from the table
*/
void
freelonode(lnode_t *lp)
{
lnode_t *lt;
lnode_t *ltprev = NULL;
struct lfsnode *lfs, *nextlfs;
struct vfs *vfsp;
struct vnode *vp = ltov(lp);
struct vnode *realvp = realvp(vp);
struct loinfo *li = vtoli(vp->v_vfsp);
#ifdef LODEBUG
lo_dprint(4, "freelonode lp %p hash %d\n",
lp, ltablehash(lp->lo_vp, li));
#endif
TABLE_LOCK_ENTER(lp->lo_vp, li);
mutex_enter(&vp->v_lock);
if (vp->v_count > 1) {
vp->v_count--; /* release our hold from vn_rele */
mutex_exit(&vp->v_lock);
TABLE_LOCK_EXIT(lp->lo_vp, li);
return;
}
mutex_exit(&vp->v_lock);
for (lt = TABLE_BUCKET(lp->lo_vp, li); lt != NULL;
ltprev = lt, lt = lt->lo_next) {
if (lt == lp) {
#ifdef LODEBUG
lo_dprint(4, "freeing %p, vfsp %p\n",
vp, vp->v_vfsp);
#endif
atomic_dec_32(&li->li_refct);
vfsp = vp->v_vfsp;
vn_invalid(vp);
if (vfsp != li->li_mountvfs) {
mutex_enter(&li->li_lfslock);
/*
* Check for unused lfs
*/
lfs = li->li_lfs;
while (lfs != NULL) {
nextlfs = lfs->lfs_next;
if (vfsp == &lfs->lfs_vfs) {
lfs_rele(lfs, li);
break;
}
if (lfs->lfs_vfs.vfs_count == 1) {
/*
* Lfs is idle
*/
freelfsnode(lfs, li);
}
lfs = nextlfs;
}
mutex_exit(&li->li_lfslock);
}
if (ltprev == NULL) {
TABLE_BUCKET(lt->lo_vp, li) = lt->lo_next;
} else {
ltprev->lo_next = lt->lo_next;
}
TABLE_COUNT(lt->lo_vp, li)--;
TABLE_LOCK_EXIT(lt->lo_vp, li);
kmem_cache_free(lnode_cache, lt);
vn_free(vp);
VN_RELE(realvp);
return;
}
}
panic("freelonode");
/*NOTREACHED*/
}