This change is the next step in implementing the cache control functionality

required by video card drivers.  Specifically, this change introduces
vm_cache_mode_t with an appropriate VM_CACHE_DEFAULT definition on all
architectures.  In addition, this changes adds a vm_cache_mode_t parameter
to kmem_alloc_contig() and vm_phys_alloc_contig().  These will be the
interfaces for allocating mapped kernel memory and physical memory,
respectively, with non-default cache modes.

In collaboration with:	jhb

1 files changed, 45 insertions, 0 deletions

diff --git a/sys/amd64/include/vm.h b/sys/amd64/include/vm.h
new file mode 100644
index 0000000..411e271
--- /dev/null
+++ b/sys/amd64/include/vm.h
@@ -0,0 +1,45 @@
+/*-
+ * Copyright (c) 2009 Advanced Computing Technologies LLC
+ * Written by: John H. Baldwin <jhb@FreeBSD.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _MACHINE_VM_H_
+#define	_MACHINE_VM_H_
+
+#include <machine/specialreg.h>
+
+/* Cache control options. */
+#define	VM_CACHE_UNCACHEABLE		((vm_cache_mode_t)PAT_UNCACHEABLE)
+#define	VM_CACHE_WRITE_COMBINING	((vm_cache_mode_t)PAT_WRITE_COMBINING)
+#define	VM_CACHE_WRITE_THROUGH		((vm_cache_mode_t)PAT_WRITE_THROUGH)
+#define	VM_CACHE_WRITE_PROTECTED	((vm_cache_mode_t)PAT_WRITE_PROTECTED)
+#define	VM_CACHE_WRITE_BACK		((vm_cache_mode_t)PAT_WRITE_BACK)
+#define	VM_CACHE_UNCACHED		((vm_cache_mode_t)PAT_UNCACHED)
+
+#define	VM_CACHE_DEFAULT		VM_CACHE_WRITE_BACK
+
+#endif /* !_MACHINE_PMAP_H_ */