For UNIX sockets make vnode point not to the socket, but to the UNIX …

…PCB,

since the latter is the thing that links together VFS and sockets.

While here, make the union in the struct vnode anonymous.

sys/kern/uipc_usrreq.c

@@ -552,7 +552,7 @@ uipc_bindat(int fd, struct socket *so, struct sockaddr *nam, struct thread *td)
 
 	UNP_LINK_WLOCK();
 	UNP_PCB_LOCK(unp);
-	VOP_UNP_BIND(vp, unp->unp_socket);
+	VOP_UNP_BIND(vp, unp);
 	unp->unp_vnode = vp;
 	unp->unp_addr = soun;
 	unp->unp_flags &= ~UNP_BINDING;
@@ -670,9 +670,6 @@ uipc_detach(struct socket *so)
 	UNP_LINK_WLOCK();
 	UNP_PCB_LOCK(unp);
 
-	/*
-	 * XXXRW: Should assert vp->v_socket == so.
-	 */
 	if ((vp = unp->unp_vnode) != NULL) {
 		VOP_UNP_DETACH(vp);
 		unp->unp_vnode = NULL;
@@ -1386,11 +1383,12 @@ unp_connectat(int fd, struct socket *so, struct sockaddr *nam,
 	 * and to protect simultaneous locking of multiple pcbs.
 	 */
 	UNP_LINK_WLOCK();
-	VOP_UNP_CONNECT(vp, &so2);
-	if (so2 == NULL) {
+	VOP_UNP_CONNECT(vp, &unp2);
+	if (unp2 == NULL) {
 		error = ECONNREFUSED;
 		goto bad2;
 	}
+	so2 = unp2->unp_socket;
 	if (so->so_type != so2->so_type) {
 		error = EPROTOTYPE;
 		goto bad2;
@@ -2454,7 +2452,6 @@ unp_scan(struct mbuf *m0, void (*op)(struct filedescent **, int))
 void
 vfs_unp_reclaim(struct vnode *vp)
 {
-	struct socket *so;
 	struct unpcb *unp;
 	int active;
 
@@ -2464,10 +2461,7 @@ vfs_unp_reclaim(struct vnode *vp)
 
 	active = 0;
 	UNP_LINK_WLOCK();
-	VOP_UNP_CONNECT(vp, &so);
-	if (so == NULL)
-		goto done;
-	unp = sotounpcb(so);
+	VOP_UNP_CONNECT(vp, &unp);
 	if (unp == NULL)
 		goto done;
 	UNP_PCB_LOCK(unp);

sys/kern/vfs_default.c

@@ -1128,23 +1128,23 @@ int
 vop_stdunp_bind(struct vop_unp_bind_args *ap)
 {
 
-	ap->a_vp->v_socket = ap->a_socket;
+	ap->a_vp->v_unpcb = ap->a_unpcb;
 	return (0);
 }
 
 int
 vop_stdunp_connect(struct vop_unp_connect_args *ap)
 {
 
-	*ap->a_socket = ap->a_vp->v_socket;
+	*ap->a_unpcb = ap->a_vp->v_unpcb;
 	return (0);
 }
 
 int
 vop_stdunp_detach(struct vop_unp_detach_args *ap)
 {
 
-	ap->a_vp->v_socket = NULL;
+	ap->a_vp->v_unpcb = NULL;
 	return (0);
 }
 

sys/kern/vfs_subr.c

@@ -2994,7 +2994,10 @@ _vdrop(struct vnode *vp, bool locked)
 	/* XXX Elsewhere we detect an already freed vnode via NULL v_op. */
 	vp->v_op = NULL;
 #endif
-	bzero(&vp->v_un, sizeof(vp->v_un));
+	vp->v_mountedhere = NULL;
+	vp->v_unpcb = NULL;
+	vp->v_rdev = NULL;
+	vp->v_fifoinfo = NULL;
 	vp->v_lasta = vp->v_clen = vp->v_cstart = vp->v_lastw = 0;
 	vp->v_iflag = 0;
 	vp->v_vflag = 0;

sys/kern/vnode_if.src

@@ -662,15 +662,15 @@ vop_advise {
 
 vop_unp_bind {
 	IN struct vnode *vp;
-	IN struct socket *socket;
+	IN struct unpcb *unpcb;
 };
 
 
 %% unp_connect	vp	L L L
 
 vop_unp_connect {
 	IN struct vnode *vp;
-	OUT struct socket **socket;
+	OUT struct unpcb **unpcb;
 };
 
 

sys/sys/vnode.h

@@ -112,14 +112,13 @@ struct vnode {
 
 	/*
 	 * Type specific fields, only one applies to any given vnode.
-	 * See #defines below for renaming to v_* namespace.
 	 */
 	union {
-		struct mount	*vu_mount;	/* v ptr to mountpoint (VDIR) */
-		struct socket	*vu_socket;	/* v unix domain net (VSOCK) */
-		struct cdev	*vu_cdev; 	/* v device (VCHR, VBLK) */
-		struct fifoinfo	*vu_fifoinfo;	/* v fifo (VFIFO) */
-	} v_un;
+		struct mount	*v_mountedhere;	/* v ptr to mountpoint (VDIR) */
+		struct unpcb	*v_unpcb;	/* v unix domain net (VSOCK) */
+		struct cdev	*v_rdev; 	/* v device (VCHR, VBLK) */
+		struct fifoinfo	*v_fifoinfo;	/* v fifo (VFIFO) */
+	};
 
 	/*
 	 * vfs_hash: (mount + inode) -> vnode hash.  The hash value
@@ -175,11 +174,6 @@ struct vnode {
 
 #endif /* defined(_KERNEL) || defined(_KVM_VNODE) */
 
-#define	v_mountedhere	v_un.vu_mount
-#define	v_socket	v_un.vu_socket
-#define	v_rdev		v_un.vu_cdev
-#define	v_fifoinfo	v_un.vu_fifoinfo
-
 #define	bo2vnode(bo)	__containerof((bo), struct vnode, v_bufobj)
 
 /* XXX: These are temporary to avoid a source sweep at this time */
@@ -200,7 +194,7 @@ struct xvnode {
 	long	xv_numoutput;			/* num of writes in progress */
 	enum	vtype xv_type;			/* vnode type */
 	union {
-		void	*xvu_socket;		/* socket, if VSOCK */
+		void	*xvu_socket;		/* unpcb, if VSOCK */
 		void	*xvu_fifo;		/* fifo, if VFIFO */
 		dev_t	xvu_rdev;		/* maj/min, if VBLK/VCHR */
 		struct {