MFamd64

 Simplify the sf_buf implementation.  In short, make it a veneer
 over the direct virtual-to-physical mapping.

1 files changed, 14 insertions, 12 deletions

diff --git a/sys/powerpc/include/sf_buf.h b/sys/powerpc/include/sf_buf.h
index b6ee1cc..6997419 100644
--- a/sys/powerpc/include/sf_buf.h
+++ b/sys/powerpc/include/sf_buf.h
@@ -29,28 +29,30 @@
 #ifndef _MACHINE_SF_BUF_H_
 #define _MACHINE_SF_BUF_H_
 
-#include <sys/queue.h>
-
-struct vm_page;
-
-struct sf_buf {
-	SLIST_ENTRY(sf_buf) free_list;	/* list of free buffer slots */
-	struct		vm_page *m;	/* currently mapped page */
-	vm_offset_t	kva;		/* va of mapping */
-};
+#include <vm/vm.h>
+#include <vm/vm_param.h>
+#include <vm/vm_page.h>
+
+/*
+ * On this machine, the only purpose for which sf_buf is used is to implement
+ * an opaque pointer required by the machine-independent parts of the kernel.
+ * That pointer references the vm_page that is "mapped" by the sf_buf.  The
+ * actual mapping is provided by the direct virtual-to-physical mapping.  
+ */
+struct sf_buf;
 
 static __inline vm_offset_t
 sf_buf_kva(struct sf_buf *sf)
 {
 
-	return (sf->kva);
+	return (VM_PAGE_TO_PHYS((vm_page_t)sf));
 }
 
-static __inline struct vm_page *
+static __inline vm_page_t
 sf_buf_page(struct sf_buf *sf)
 {
 
-	return (sf->m);
+	return ((vm_page_t)sf);
 }
 
 #endif /* !_MACHINE_SF_BUF_H_ */