[src/trunk]: src/sys/miscfs/genfs Provide EVFILT_WRITE; this is what FreeBSD ...

[christos <christos%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/51f71eddc19a
branches:  trunk
changeset: 354850:51f71eddc19a
user:      christos <christos%NetBSD.org@localhost>
date:      Sat Jul 01 20:07:00 2017 +0000

description:
Provide EVFILT_WRITE; this is what FreeBSD does and go wants it.
Makes go unit tests pass.

diffstat:

 sys/miscfs/genfs/genfs_vnops.c |  35 +++++++++++++++++++++++++++++++++--
 1 files changed, 33 insertions(+), 2 deletions(-)

diffs (70 lines):

diff -r b9f5e1af9c0f -r 51f71eddc19a sys/miscfs/genfs/genfs_vnops.c
--- a/sys/miscfs/genfs/genfs_vnops.c    Sat Jul 01 16:59:12 2017 +0000
+++ b/sys/miscfs/genfs/genfs_vnops.c    Sat Jul 01 20:07:00 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: genfs_vnops.c,v 1.197 2017/06/04 08:02:26 hannken Exp $        */
+/*     $NetBSD: genfs_vnops.c,v 1.198 2017/07/01 20:07:00 christos Exp $       */
 
 /*-
  * Copyright (c) 2008 The NetBSD Foundation, Inc.
@@ -57,7 +57,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: genfs_vnops.c,v 1.197 2017/06/04 08:02:26 hannken Exp $");
+__KERNEL_RCSID(0, "$NetBSD: genfs_vnops.c,v 1.198 2017/07/01 20:07:00 christos Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -500,6 +500,32 @@
 }
 
 static int
+filt_genfswrite(struct knote *kn, long hint)
+{
+       struct vnode *vp = (struct vnode *)kn->kn_hook;
+
+       /*
+        * filesystem is gone, so set the EOF flag and schedule
+        * the knote for deletion.
+        */
+       switch (hint) {
+       case NOTE_REVOKE:
+               KASSERT(mutex_owned(vp->v_interlock));
+               kn->kn_flags |= (EV_EOF | EV_ONESHOT);
+               return (1);
+       case 0:
+               mutex_enter(vp->v_interlock);
+               kn->kn_data = 0;
+               mutex_exit(vp->v_interlock);
+               return 1;
+       default:
+               KASSERT(mutex_owned(vp->v_interlock));
+               kn->kn_data = 0;
+               return 1;
+       }
+}
+
+static int
 filt_genfsvnode(struct knote *kn, long hint)
 {
        struct vnode *vp = (struct vnode *)kn->kn_hook;
@@ -530,6 +556,8 @@
 
 static const struct filterops genfsread_filtops =
        { 1, NULL, filt_genfsdetach, filt_genfsread };
+static const struct filterops genfswrite_filtops =
+       { 1, NULL, filt_genfsdetach, filt_genfswrite };
 static const struct filterops genfsvnode_filtops =
        { 1, NULL, filt_genfsdetach, filt_genfsvnode };
 
@@ -549,6 +577,9 @@
        case EVFILT_READ:
                kn->kn_fop = &genfsread_filtops;
                break;
+       case EVFILT_WRITE:
+               kn->kn_fop = &genfswrite_filtops;
+               break;
        case EVFILT_VNODE:
                kn->kn_fop = &genfsvnode_filtops;
                break;