Index: src/sys/kern/kern_event.c
===================================================================
--- src/sys/kern/kern_event.c	(revision 163)
+++ src/sys/kern/kern_event.c	(working copy)
@@ -45,8 +45,10 @@
 #include <sys/queue.h>
 #include <sys/event.h>
 #include <sys/eventvar.h>
+#include <sys/namei.h>
 #include <sys/poll.h>
 #include <sys/protosw.h>
+#include <sys/resourcevar.h>
 #include <sys/sigio.h>
 #include <sys/signalvar.h>
 #include <sys/socket.h>
@@ -57,6 +59,7 @@
 #include <sys/syscallsubr.h>
 #include <sys/taskqueue.h>
 #include <sys/uio.h>
+#include <sys/vnode.h>
 
 #include <vm/uma.h>
 
@@ -132,6 +135,9 @@
 static int	filt_timerattach(struct knote *kn);
 static void	filt_timerdetach(struct knote *kn);
 static int	filt_timer(struct knote *kn, long hint);
+static int	filt_nvnodeattach(struct knote *kn);
+static void	filt_nvnodedetach(struct knote *kn);
+static int	filt_nvnode(struct knote *kn, long hint);
 
 static struct filterops file_filtops =
 	{ 1, filt_fileattach, NULL, NULL };
@@ -142,6 +148,8 @@
 	{ 0, filt_procattach, filt_procdetach, filt_proc };
 static struct filterops timer_filtops =
 	{ 0, filt_timerattach, filt_timerdetach, filt_timer };
+static struct filterops nvnode_filtops =
+	{ 0, filt_nvnodeattach, filt_nvnodedetach, filt_nvnode };
 
 static uma_zone_t	knote_zone;
 static int 		kq_ncallouts = 0;
@@ -228,6 +236,7 @@
 	{ &timer_filtops },			/* EVFILT_TIMER */
 	{ &file_filtops },			/* EVFILT_NETDEV */
 	{ &fs_filtops },			/* EVFILT_FS */
+	{ &nvnode_filtops },			/* EVFILT_NAMEDVNODE */
 };
 
 /*
@@ -478,7 +487,91 @@
 	return (kn->kn_data != 0);
 }
 
+static int maxwatchedvnodes = 8192;
+
+SYSCTL_INT(_kern, OID_AUTO, maxwatchedvnodes, CTLFLAG_RW,
+    &maxwatchedvnodes, 0, "Maximum number of watched vnodes by kqueue per "
+    "user");
+
 /*
+ * Attaches a knote to a vnode found from a path.
+ * Note: The vnode does not get vput().
+ */
+static int
+filt_nvnodeattach(struct knote *kn)
+{
+	struct vnode *vp;	
+	struct nameidata nd;
+	struct uidinfo *uip;
+	int error, vfslocked;
+
+	error = 0;
+
+	NDINIT(&nd, LOOKUP, NOFOLLOW | LOCKLEAF, UIO_SYSSPACE,
+	    (char *)kn->kn_id, curthread);
+
+	if ((error = namei(&nd)) != 0)
+		return (error);
+
+	vfslocked = NDHASGIANT(&nd);
+	vp = nd.ni_vp;
+	kn->kn_hook = vp;
+
+	if (vp->v_pollinfo == NULL)
+		v_addpollinfo(vp);
+	if (vp->v_pollinfo == NULL) {
+		error = ENOMEM;
+		goto done;
+	}
+
+	uip = curthread->td_ucred->cr_uidinfo;
+	UIDINFO_LOCK(uip);
+	if (uip->ui_watchedvnodes >= maxwatchedvnodes) {
+		UIDINFO_UNLOCK(uip);
+		error = EMFILE;
+		goto done;
+	}
+	uip->ui_watchedvnodes++;
+	UIDINFO_UNLOCK(uip);
+
+	knlist_add(&vp->v_pollinfo->vpi_selinfo.si_note, kn, 0);
+done:
+	NDFREE(&nd, NDF_ONLY_PNBUF);
+	VOP_UNLOCK(vp, 0, curthread);
+	VFS_UNLOCK_GIANT(vfslocked);
+
+	return (error);
+}
+
+static void
+filt_nvnodedetach(struct knote *kn)
+{
+	struct uidinfo *uip;
+	struct vnode *vp;
+
+	vp = (struct vnode *)kn->kn_hook;
+	KASSERT(vp->v_pollinfo != NULL, ("Missing v_pollinfo"));
+        uip = curthread->td_ucred->cr_uidinfo;
+        UIDINFO_LOCK(uip);
+	uip->ui_watchedvnodes--;
+	UIDINFO_UNLOCK(uip);
+	knlist_remove(&vp->v_pollinfo->vpi_selinfo.si_note, kn, 0);
+	vrele(vp);
+}
+
+static int
+filt_nvnode(struct knote *kn, long hint)
+{
+	if (kn->kn_sfflags & hint)
+		kn->kn_fflags |= hint;
+	if (hint & NOTE_REVOKE) {
+		kn->kn_flags |= EV_EOF;
+		return (1);
+	}
+	return (kn->kn_fflags != 0);
+}
+
+/*
  * MPSAFE
  */
 int
Index: src/sys/sys/resourcevar.h
===================================================================
--- src/sys/sys/resourcevar.h	(revision 163)
+++ src/sys/sys/resourcevar.h	(working copy)
@@ -99,6 +99,7 @@
 	long	ui_proccnt;		/* (b) number of processes */
 	uid_t	ui_uid;			/* (a) uid */
 	u_int	ui_ref;			/* (b) reference count */
+	long	ui_watchedvnodes;	/* (b) number of watched vnodes */
 	struct mtx *ui_mtxp;		/* protect all counts/limits */
 };
 
Index: src/sys/sys/event.h
===================================================================
--- src/sys/sys/event.h	(revision 163)
+++ src/sys/sys/event.h	(working copy)
@@ -38,8 +38,9 @@
 #define EVFILT_TIMER		(-7)	/* timers */
 #define EVFILT_NETDEV		(-8)	/* network devices */
 #define EVFILT_FS		(-9)	/* filesystem events */
+#define EVFILT_NAMEDVNODE	(-10)	/* vnodes from paths */
 
-#define EVFILT_SYSCOUNT		9
+#define EVFILT_SYSCOUNT		10
 
 #define EV_SET(kevp_, a, b, c, d, e, f) do {	\
 	struct kevent *kevp = (kevp_);		\