Add a new option, OBJPR_NOTMAPPED, to vm_object_page_remove(). Passing this

option to vm_object_page_remove() asserts that the specified range of pages
is not mapped, or more precisely that none of these pages have any managed
mappings.  Thus, vm_object_page_remove() need not call pmap_remove_all() on
the pages.

This change not only saves time by eliminating pointless calls to
pmap_remove_all(), but it also eliminates an inconsistency in the use of
pmap_remove_all() versus related functions, like pmap_remove_write().  It
eliminates harmless but pointless calls to pmap_remove_all() that were being
performed on PG_UNMANAGED pages.

Update all of the existing assertions on pmap_remove_all() to reflect this
change.

Reviewed by:	kib

1 files changed, 8 insertions, 1 deletions

diff --git a/sys/vm/vm_object.h b/sys/vm/vm_object.h
index 0f4f47d..a11f144 100644
--- a/sys/vm/vm_object.h
+++ b/sys/vm/vm_object.h
@@ -168,6 +168,12 @@ struct vm_object {
 #define OBJPC_INVAL	0x2			/* invalidate */
 #define OBJPC_NOSYNC	0x4			/* skip if PG_NOSYNC */
 
+/*
+ * The following options are supported by vm_object_page_remove().
+ */
+#define	OBJPR_CLEANONLY	0x1		/* Don't remove dirty pages. */
+#define	OBJPR_NOTMAPPED	0x2		/* Don't unmap pages. */
+
 TAILQ_HEAD(object_q, vm_object);
 
 extern struct object_q vm_object_list;	/* list of allocated objects */
@@ -219,7 +225,8 @@ void vm_object_set_writeable_dirty (vm_object_t);
 void vm_object_init (void);
 void vm_object_page_clean(vm_object_t object, vm_ooffset_t start,
     vm_ooffset_t end, int flags);
-void vm_object_page_remove (vm_object_t, vm_pindex_t, vm_pindex_t, boolean_t);
+void vm_object_page_remove(vm_object_t object, vm_pindex_t start,
+    vm_pindex_t end, int options);
 boolean_t vm_object_populate(vm_object_t, vm_pindex_t, vm_pindex_t);
 void vm_object_print(long addr, boolean_t have_addr, long count, char *modif);
 void vm_object_reference (vm_object_t);