From 572d1df4bc37d9f36a99792bb35a44fb05ad0066 Mon Sep 17 00:00:00 2001
From: Mike Hibler <hibler@ucbvax.Berkeley.EDU>
Date: Fri, 27 May 1994 22:28:11 -0800
Subject: [PATCH] back out change requiring alignment of "pos" also don't
 require that munmap range be completely allocated

SCCS-vsn: sys/vm/vm_mmap.c 8.7
---
 usr/src/sys/vm/vm_mmap.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/usr/src/sys/vm/vm_mmap.c b/usr/src/sys/vm/vm_mmap.c
index 73de83c866..9c8f3ff3eb 100644
--- a/usr/src/sys/vm/vm_mmap.c
+++ b/usr/src/sys/vm/vm_mmap.c
@@ -11,7 +11,7 @@
  *
  * from: Utah $Hdr: vm_mmap.c 1.6 91/10/21$
  *
- *	@(#)vm_mmap.c	8.6 (Berkeley) %G%
+ *	@(#)vm_mmap.c	8.7 (Berkeley) %G%
  */
 
 /*
@@ -179,10 +179,17 @@ mmap(p, uap, retval)
 	/*
 	 * Address (if FIXED) must be page aligned.
 	 * Size is implicitly rounded to a page boundary.
+	 *
+	 * XXX most (all?) vendors require that the file offset be
+	 * page aligned as well.  However, we already have applications
+	 * (e.g. nlist) that rely on unrestricted alignment.  Since we
+	 * support it, let it happen.
 	 */
 	addr = (vm_offset_t) uap->addr;
 	if (((flags & MAP_FIXED) && (addr & PAGE_MASK)) ||
+#if 0
 	    ((flags & MAP_ANON) == 0 && (pos & PAGE_MASK)) ||
+#endif
 	    (ssize_t)uap->len < 0 || ((flags & MAP_ANON) && uap->fd != -1))
 		return (EINVAL);
 	size = (vm_size_t) round_page(uap->len);
@@ -385,9 +392,12 @@ munmap(p, uap, retval)
 	map = &p->p_vmspace->vm_map;
 	/*
 	 * Make sure entire range is allocated.
+	 * XXX this seemed overly restrictive, so we relaxed it.
 	 */
+#if 0
 	if (!vm_map_check_protection(map, addr, addr + size, VM_PROT_NONE))
 		return(EINVAL);
+#endif
 	/* returns nothing but KERN_SUCCESS anyway */
 	(void) vm_map_remove(map, addr, addr+size);
 	return(0);
-- 
2.20.1