[src/trunk]: src/sys/arch/usermode/usermode Implement switch to have a sparse...

[reinoud <reinoud%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/e1d763e2ada4
branches:  trunk
changeset: 769301:e1d763e2ada4
user:      reinoud <reinoud%NetBSD.org@localhost>
date:      Tue Sep 06 09:37:41 2011 +0000

description:
Implement switch to have a sparse memory file or to fill it beforehand.

diffstat:

 sys/arch/usermode/usermode/pmap.c |  38 +++++++++++++++++++++++++++++++-------
 1 files changed, 31 insertions(+), 7 deletions(-)

diffs (80 lines):

diff -r 38fe8a3fa0c0 -r e1d763e2ada4 sys/arch/usermode/usermode/pmap.c
--- a/sys/arch/usermode/usermode/pmap.c Tue Sep 06 08:44:39 2011 +0000
+++ b/sys/arch/usermode/usermode/pmap.c Tue Sep 06 09:37:41 2011 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: pmap.c,v 1.56 2011/09/06 08:44:39 reinoud Exp $ */
+/* $NetBSD: pmap.c,v 1.57 2011/09/06 09:37:41 reinoud Exp $ */
 
 /*-
  * Copyright (c) 2011 Reinoud Zandijk <reinoud%NetBSD.org@localhost>
@@ -27,7 +27,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.56 2011/09/06 08:44:39 reinoud Exp $");
+__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.57 2011/09/06 09:37:41 reinoud Exp $");
 
 #include "opt_memsize.h"
 #include "opt_kmempages.h"
@@ -104,6 +104,8 @@
 vaddr_t kmem_user_start, kmem_user_end;
 vaddr_t kmem_ext_cur_start, kmem_ext_cur_end;
 
+#define SPARSE_MEMFILE
+
 void
 pmap_bootstrap(void)
 {
@@ -119,7 +121,6 @@
        vaddr_t va;
        uintptr_t pg;
        void *addr;
-       char dummy;
        int err;
 
        extern void _init(void);        /* start of kernel               */
@@ -188,7 +189,7 @@
        aprint_debug("\tkmem_ext_end\t%p\n",    (void *) kmem_ext_end);
        aprint_debug("\tkmem_user_start\t%p\n", (void *) kmem_user_start);
        aprint_debug("\tkmem_user_end\t%p\n",   (void *) kmem_user_end);
-       aprint_debug("\n\n\n");
+       aprint_debug("\n\n");
 
        aprint_debug("Creating memory mapped backend\n");
 
@@ -203,9 +204,32 @@
 
        /* file_len is the backing store length, nothing to do with placement */
        file_len = 1024 * MEMSIZE;
-       wlen = thunk_pwrite(mem_fh, &dummy, 1, file_len - 1);
-       if (wlen != 1)
-               panic("pmap_bootstrap: can't grow file\n");
+
+#ifdef SPARSE_MEMFILE
+       {
+               char dummy;
+
+               wlen = thunk_pwrite(mem_fh, &dummy, 1, file_len - 1);
+               if (wlen != 1)
+                       panic("pmap_bootstrap: can't grow file\n");
+       }
+#else
+       {
+               void *block;
+
+               printf("Creating memory file\r");
+               block = thunk_malloc(PAGE_SIZE);
+               if (!block)
+                       panic("pmap_bootstrap: can't malloc writeout block");
+
+               for (pg = 0; pg < file_len; pg += PAGE_SIZE) {
+                       wlen = thunk_pwrite(mem_fh, block, PAGE_SIZE, pg);
+                       if (wlen != PAGE_SIZE)
+                               panic("pmap_bootstrap: write fails, disc full?");
+               }
+               thunk_free(block);
+       }
+#endif
 
        /* protect the current kernel section */
        /* XXX kernel stack? */