1 files changed, 100 insertions, 0 deletions
diff --git a/sys/vm/default_pager.c b/sys/vm/default_pager.c
new file mode 100644
index 0000000..7bbb99f
--- /dev/null
+++ b/sys/vm/default_pager.c
@@ -0,0 +1,100 @@
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/kernel.h>
+#include <sys/malloc.h>
+
+#include <vm/vm.h>
+#include <vm/vm_pager.h>
+#include <vm/vm_page.h>
+#include <vm/default_pager.h>
+#include <vm/swap_pager.h>
+
+/*
+ * pagerops for OBJT_DEFAULT - "default pager".
+ */
+struct pagerops defaultpagerops = {
+	NULL,
+	default_pager_alloc,
+	default_pager_dealloc,
+	default_pager_getpages,
+	default_pager_putpages,
+	default_pager_haspage,
+	NULL
+};
+
+/*
+ * no_pager_alloc just returns an initialized object.
+ */
+vm_object_t
+default_pager_alloc(handle, size, prot, offset)
+	void *handle;
+	register vm_size_t size;
+	vm_prot_t prot;
+	vm_offset_t offset;
+{
+	if (handle != NULL)
+		panic("default_pager_alloc: handle specified");
+
+	return vm_object_allocate(OBJT_DEFAULT, offset + size);
+}
+
+void
+default_pager_dealloc(object)
+	vm_object_t object;
+{
+	/*
+	 * OBJT_DEFAULT objects have no special resources allocated to them.
+	 */
+}
+
+/*
+ * The default pager has no backing store, so we always return
+ * failure.
+ */
+int
+default_pager_getpages(object, m, count, reqpage)
+	vm_object_t object;
+	vm_page_t *m;
+	int count;
+	int reqpage;
+{
+	return VM_PAGER_FAIL;
+}
+
+int
+default_pager_putpages(object, m, c, sync, rtvals)
+	vm_object_t object;
+	vm_page_t *m;
+	int c;
+	boolean_t sync;
+	int *rtvals;
+{
+	int i;
+
+	/*
+	 * Try to convert the object type into a OBJT_SWAP.
+	 * If the swp structure allocation fails, convert it
+	 * back to OBJT_DEFAULT and return failure. Otherwise
+	 * pass this putpages to the swap pager.
+	 */
+	object->type = OBJT_SWAP;
+
+	if (swap_pager_swp_alloc(object, M_KERNEL) != 0) {
+		object->type = OBJT_DEFAULT;
+		for (i = 0; i < c; i++)
+			rtvals[i] = VM_PAGER_FAIL;
+		return VM_PAGER_FAIL;
+	}
+
+	return swap_pager_putpages(object, m, c, sync, rtvals);
+}
+
+boolean_t
+default_pager_haspage(object, offset, before, after)
+	vm_object_t object;
+	vm_offset_t offset;
+	int *before;
+	int *after;
+{
+	return FALSE;
+}