/*
* Returns non-zero (1) if the vnodeops matches that of the vnode.
* Returns zero (0) if not.
*/
int
vn_matchops(vnode_t * vp, vnodeops_t * vnodeops)
{
return (vn_getops(vp) == vnodeops);
}
/*
* Create a reference to the vnode representing the file descriptor.
* Then, apply the VOP_OPEN operation to that vnode.
*
* The vnode for the file descriptor may be switched under you.
* If it is, search the hash list for an nodep - nodep->nm_filevp
* pair. If it exists, return that nodep to the user.
* If it does not exist, create a new namenode to attach
* to the nodep->nm_filevp then place the pair on the hash list.
*
* Newly created objects are like children/nodes in the mounted
* file system, with the parent being the initial mount.
*/
int
nm_open(vnode_t **vpp, int flag, cred_t *crp, caller_context_t *ct)
{
struct namenode *nodep = VTONM(*vpp);
int error = 0;
struct namenode *newnamep;
struct vnode *newvp;
struct vnode *infilevp;
struct vnode *outfilevp;
/*
* If the vnode is switched under us, the corresponding
* VN_RELE for this VN_HOLD will be done by the file system
* performing the switch. Otherwise, the corresponding
* VN_RELE will be done by nm_close().
*/
infilevp = outfilevp = nodep->nm_filevp;
VN_HOLD(outfilevp);
if ((error = VOP_OPEN(&outfilevp, flag, crp, ct)) != 0) {
VN_RELE(outfilevp);
return (error);
}
if (infilevp != outfilevp) {
/*
* See if the new filevp (outfilevp) is already associated
* with the mount point. If it is, then it already has a
* namenode associated with it.
*/
mutex_enter(&ntable_lock);
if ((newnamep =
namefind(outfilevp, nodep->nm_mountpt)) != NULL) {
struct vnode *vp = NMTOV(newnamep);
VN_HOLD(vp);
goto gotit;
}
newnamep = kmem_zalloc(sizeof (struct namenode), KM_SLEEP);
newvp = vn_alloc(KM_SLEEP);
newnamep->nm_vnode = newvp;
mutex_init(&newnamep->nm_lock, NULL, MUTEX_DEFAULT, NULL);
mutex_enter(&nodep->nm_lock);
newvp->v_flag = ((*vpp)->v_flag | VNOMAP | VNOSWAP) & ~VROOT;
vn_setops(newvp, vn_getops(*vpp));
newvp->v_vfsp = &namevfs;
newvp->v_stream = outfilevp->v_stream;
newvp->v_type = outfilevp->v_type;
newvp->v_rdev = outfilevp->v_rdev;
newvp->v_data = (caddr_t)newnamep;
vn_exists(newvp);
bcopy(&nodep->nm_vattr, &newnamep->nm_vattr, sizeof (vattr_t));
newnamep->nm_vattr.va_type = outfilevp->v_type;
newnamep->nm_vattr.va_nodeid = namenodeno_alloc();
newnamep->nm_vattr.va_size = (u_offset_t)0;
newnamep->nm_vattr.va_rdev = outfilevp->v_rdev;
newnamep->nm_flag = NMNMNT;
newnamep->nm_filevp = outfilevp;
newnamep->nm_filep = nodep->nm_filep;
newnamep->nm_mountpt = nodep->nm_mountpt;
mutex_exit(&nodep->nm_lock);
/*
* Insert the new namenode into the hash list.
*/
nameinsert(newnamep);
gotit:
mutex_exit(&ntable_lock);
/*
* Release the above reference to the infilevp, the reference
* to the NAMEFS vnode, create a reference to the new vnode
* and return the new vnode to the user.
*/
VN_RELE(*vpp);
*vpp = NMTOV(newnamep);
}
return (0);
}
