From f5097eede22ca7994d4d1cc41eefca2987debac6 Mon Sep 17 00:00:00 2001
From: bluhm <bluhm@openbsd.org>
Date: Fri, 7 Jul 2023 20:38:17 +0000
Subject: [PATCH] Implement route reference counting mockup poperly in rtable
 regress. This allows to change rtable implementation in kernel without
 breaking test.

---
 regress/sys/net/rtable/kern_compat.h |  8 +++--
 regress/sys/net/rtable/util.c        | 53 ++++++++++++++++++++++++++--
 regress/sys/net/rtable/util.h        |  2 +-
 3 files changed, 56 insertions(+), 7 deletions(-)

diff --git a/regress/sys/net/rtable/kern_compat.h b/regress/sys/net/rtable/kern_compat.h
index 5fc616d946f..80e40a26350 100644
--- a/regress/sys/net/rtable/kern_compat.h
+++ b/regress/sys/net/rtable/kern_compat.h
@@ -1,8 +1,12 @@
-/*	$OpenBSD: kern_compat.h,v 1.14 2023/04/18 16:57:44 bluhm Exp $	*/
+/*	$OpenBSD: kern_compat.h,v 1.15 2023/07/07 20:38:17 bluhm Exp $	*/
 
 #ifndef _KERN_COMPAT_H_
 #define _KERN_COMPAT_H_
 
+#define _KERNEL
+#include <sys/refcnt.h>
+#undef _KERNEL
+
 #include <sys/socket.h>
 #include <sys/domain.h>
 #include <sys/queue.h>
@@ -78,8 +82,6 @@ extern struct domain *domains[];
 #define rw_exit_write(rwl)
 #define rw_assert_wrlock(rwl)
 
-#define refcnt_read(cnt)	1
-
 #define SET(t, f)	((t) |= (f))
 #define CLR(t, f)	((t) &= ~(f))
 #define ISSET(t, f)	((t) & (f))
diff --git a/regress/sys/net/rtable/util.c b/regress/sys/net/rtable/util.c
index b948d231cc5..58cc81ec2b8 100644
--- a/regress/sys/net/rtable/util.c
+++ b/regress/sys/net/rtable/util.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: util.c,v 1.12 2022/11/23 14:51:00 kn Exp $ */
+/*	$OpenBSD: util.c,v 1.13 2023/07/07 20:38:17 bluhm Exp $ */
 
 /*
  * Copyright (c) 2015 Martin Pieuchot
@@ -44,6 +44,10 @@
  * SUCH DAMAGE.
  */
 
+#define _KERNEL
+#include <sys/refcnt.h>
+#undef _KERNEL
+
 #include "srp_compat.h"
 
 #include <sys/socket.h>
@@ -112,6 +116,7 @@ route_insert(unsigned int rid, sa_family_t af, char *string)
 	rt = calloc(1, sizeof(*rt));
 	if (rt == NULL)
 		errx(1, "out of memory");
+	refcnt_init(&rt->rt_refcnt);
 
 	plen = inet_net_ptosa(af, string, dst, mask);
 	if (plen == -1)
@@ -132,6 +137,8 @@ route_insert(unsigned int rid, sa_family_t af, char *string)
 		inet_net_satop(af, rt_key(rt), plen, ip, sizeof(ip));
 		errx(1, "added route not found: %s\n", ip);
 	}
+	rtfree(rt);
+	rtfree(nrt);
 }
 
 /*
@@ -173,6 +180,9 @@ route_delete(unsigned int rid, sa_family_t af, char *string)
 		errx(1, "found: %s after deleting: %s", ip, ip0);
 	}
 
+	rtfree(rt);
+	assert(refcnt_read(&rt->rt_refcnt) == 0);
+
 	free(rt_key(rt));
 	free(rt);
 }
@@ -201,6 +211,8 @@ route_lookup(unsigned int rid, sa_family_t af, char *string)
 	}
 	assert(memcmp(rt_key(rt), dst, dst->sa_len) == 0);
 	assert(rt_plen(rt) == rtable_satoplen(af, mask));
+
+	rtfree(rt);
 }
 
 int
@@ -254,6 +266,7 @@ rtentry_delete(struct rtentry *rt, void *w, unsigned int rid)
 		inet_net_satop(af, rt_key(rt), rt_plen(rt), dest, sizeof(dest));
 		errx(1, "can't rm route: %s, %s\n", dest, strerror(error));
 	}
+	assert(refcnt_read(&rt->rt_refcnt) == 0);
 
 	return (0);
 }
@@ -281,13 +294,47 @@ rt_maskedcopy(struct sockaddr *src, struct sockaddr *dst,
 void
 rtref(struct rtentry *rt)
 {
-	rt->rt_refcnt.r_refs++;
+	refcnt_take(&rt->rt_refcnt);
 }
 
 void
 rtfree(struct rtentry *rt)
 {
-	assert(--(rt->rt_refcnt.r_refs) >= 0);
+	if (refcnt_rele(&rt->rt_refcnt) == 0)
+		return;
+}
+
+void
+refcnt_init(struct refcnt *r)
+{
+	r->r_refs = 1;
+}
+
+void
+refcnt_take(struct refcnt *r)
+{
+	u_int refs;
+
+	refs = ++r->r_refs;
+	assert(refs != 0);
+}
+
+int
+refcnt_rele(struct refcnt *r)
+{
+	u_int refs;
+
+	refs = --r->r_refs;
+	assert(refs != ~0);
+	if (r->r_refs == 0)
+		return (1);
+	return (0);
+}
+
+unsigned int
+refcnt_read(struct refcnt *r)
+{
+	return (r->r_refs);
 }
 
 void
diff --git a/regress/sys/net/rtable/util.h b/regress/sys/net/rtable/util.h
index 99529c0c5a0..8b0c24a77da 100644
--- a/regress/sys/net/rtable/util.h
+++ b/regress/sys/net/rtable/util.h
@@ -1,4 +1,4 @@
-/* 	$OpenBSD: util.h,v 1.4 2020/11/07 09:53:21 denis Exp $ */
+/*	$OpenBSD: util.h,v 1.5 2023/07/07 20:38:17 bluhm Exp $	*/
 
 /*
  * Copyright (c) 2015 Martin Pieuchot
-- 
2.20.1