1 files changed, 40 insertions, 0 deletions
diff --git a/libpager/pagemap.c b/libpager/pagemap.c
new file mode 100644
index 00000000..c09a4d04
--- /dev/null
+++ b/libpager/pagemap.c
@@ -0,0 +1,40 @@
+/* Pagemap manipulation for pager library
+   Copyright (C) 1994 Free Software Foundation
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2, or (at
+   your option) any later version.
+
+   This program is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
+
+  
+/* Grow the pagemap as necessary to deal with address OFF */
+void
+pagemap_resize (struct pager *p,
+		int off)
+{
+  void *newaddr;
+  int newsize;
+  
+  if (p->pagemapsize && !p->pagemap)
+    panic ("pagemap failure");
+
+  off /= __vm_page_size;
+  if (p->pagemapsize >= off)
+    return;
+  
+  newsize = round_page (off);
+  vm_allocate (mach_task_self (), (u_int *)&newaddr, newsize, 1);
+  bcopy (p->pagemap, newaddr, p->pagemapsize);
+  vm_deallocate (mach_task_self (), (u_int)p->pagemap, p->pagemapsize);
+  p->pagemap = newaddr;
+  p->pagemapsize = newsize;
+}