Allow EVFILT_VNODE events to work on every filesystem type, not just

UFS by:
- Making the pre and post hooks for the VOP functions work even when
DEBUG_VFS_LOCKS is not defined.
- Moving the KNOTE activations into the corresponding VOP hooks.
- Creating a MNTK_NOKNOTE flag for the mnt_kern_flag field of struct
mount that permits filesystems to disable the new behavior.
- Creating a default VOP_KQFILTER function: vfs_kqfilter()

My benchmarks have not revealed any performance degradation.

Reviewed by:	jeff, bde
Approved by:	rwatson, jmg (kqueue changes), grehan (mentor)

1 files changed, 8 insertions, 0 deletions

diff --git a/sys/kern/vfs_default.c b/sys/kern/vfs_default.c
index 32f3f9b..2336438 100644
--- a/sys/kern/vfs_default.c
+++ b/sys/kern/vfs_default.c
@@ -40,6 +40,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/bio.h>
 #include <sys/buf.h>
 #include <sys/conf.h>
+#include <sys/event.h>
 #include <sys/kernel.h>
 #include <sys/limits.h>
 #include <sys/lock.h>
@@ -82,6 +83,7 @@ struct vop_vector default_vnodeops = {
 	.vop_getwritemount = 	vop_stdgetwritemount,
 	.vop_inactive =		VOP_NULL,
 	.vop_ioctl =		VOP_ENOTTY,
+	.vop_kqfilter =		vop_stdkqfilter,
 	.vop_islocked =		vop_stdislocked,
 	.vop_lease =		VOP_NULL,
 	.vop_lock =		vop_stdlock,
@@ -464,6 +466,12 @@ vop_stdgetpages(ap)
 	    ap->a_count, ap->a_reqpage);
 }
 
+int
+vop_stdkqfilter(struct vop_kqfilter_args *ap)
+{
+	return vfs_kqfilter(ap);
+}
+
 /* XXX Needs good comment and more info in the manpage (VOP_PUTPAGES(9)). */
 int
 vop_stdputpages(ap)