From 19ea042eb870468a68651adbc0791e4ce3c21843 Mon Sep 17 00:00:00 2001
From: Konstantin Belousov <kib@FreeBSD.org>
Date: Fri, 30 Mar 2018 10:55:31 +0000
Subject: [PATCH] Make vm_map_max/min/pmap KBI stable.

There are out of tree consumers of vm_map_min() and vm_map_max(), and
I believe there are consumers of vm_map_pmap(), although the later is
arguably less in the need of KBI-stable interface. For the consumers
benefit, make modules using this KPI not depended on the struct vm_map
layout.

Reviewed by:	alc, markj
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D14902
---
 sys/vm/vm_map.c | 21 +++++++++++++++++++++
 sys/vm/vm_map.h |  9 +++++++++
 2 files changed, 30 insertions(+)

diff --git a/sys/vm/vm_map.c b/sys/vm/vm_map.c
index 65c009003d8..1ce2435fe3c 100644
--- a/sys/vm/vm_map.c
+++ b/sys/vm/vm_map.c
@@ -4315,6 +4315,27 @@ vm_map_lookup_done(vm_map_t map, vm_map_entry_t entry)
 	vm_map_unlock_read(map);
 }
 
+vm_offset_t
+vm_map_max_KBI(const struct vm_map *map)
+{
+
+	return (map->max_offset);
+}
+
+vm_offset_t
+vm_map_min_KBI(const struct vm_map *map)
+{
+
+	return (map->min_offset);
+}
+
+pmap_t
+vm_map_pmap_KBI(vm_map_t map)
+{
+
+	return (map->pmap);
+}
+
 #include "opt_ddb.h"
 #ifdef DDB
 #include <sys/kernel.h>
diff --git a/sys/vm/vm_map.h b/sys/vm/vm_map.h
index bc6371006ce..65b8f23ce58 100644
--- a/sys/vm/vm_map.h
+++ b/sys/vm/vm_map.h
@@ -206,6 +206,11 @@ struct vm_map {
 #define	MAP_BUSY_WAKEUP		0x02
 
 #ifdef	_KERNEL
+#ifdef KLD_MODULE
+#define	vm_map_max(map)		vm_map_max_KBI((map))
+#define	vm_map_min(map)		vm_map_min_KBI((map))
+#define	vm_map_pmap(map)	vm_map_pmap_KBI((map))
+#else
 static __inline vm_offset_t
 vm_map_max(const struct vm_map *map)
 {
@@ -229,6 +234,7 @@ vm_map_modflags(vm_map_t map, vm_flags_t set, vm_flags_t clear)
 {
 	map->flags = (map->flags | set) & ~clear;
 }
+#endif	/* KLD_MODULE */
 #endif	/* _KERNEL */
 
 /*
@@ -289,6 +295,9 @@ void vm_map_wakeup(vm_map_t map);
 void vm_map_busy(vm_map_t map);
 void vm_map_unbusy(vm_map_t map);
 void vm_map_wait_busy(vm_map_t map);
+vm_offset_t vm_map_max_KBI(const struct vm_map *map);
+vm_offset_t vm_map_min_KBI(const struct vm_map *map);
+pmap_t vm_map_pmap_KBI(vm_map_t map);
 
 #define	vm_map_lock(map)	_vm_map_lock(map, LOCK_FILE, LOCK_LINE)
 #define	vm_map_unlock(map)	_vm_map_unlock(map, LOCK_FILE, LOCK_LINE)