1 files changed, 33 insertions, 0 deletions
diff --git a/sys/vm/vnode_pager.c b/sys/vm/vnode_pager.c
index 1b0dc7e..817516d 100644
--- a/sys/vm/vnode_pager.c
+++ b/sys/vm/vnode_pager.c
@@ -665,6 +665,39 @@ vnode_pager_getpages(vm_object_t object, vm_page_t *m, int count, int reqpage)
 }
 
 /*
+ * The implementation of VOP_GETPAGES() for local filesystems, where
+ * partially valid pages can only occur at the end of file.
+ */
+int
+vnode_pager_local_getpages(struct vop_getpages_args *ap)
+{
+	vm_page_t mreq;
+
+	mreq = ap->a_m[ap->a_reqpage];
+
+	/*
+	 * Since the caller has busied the requested page, that page's valid
+	 * field will not be changed by other threads.
+	 */
+	vm_page_assert_xbusied(mreq);
+
+	/*
+	 * The requested page has valid blocks.  Invalid part can only
+	 * exist at the end of file, and the page is made fully valid
+	 * by zeroing in vm_pager_getpages().  Free non-requested
+	 * pages, since no i/o is done to read its content.
+	 */
+	if (mreq->valid != 0) {
+		vm_pager_free_nonreq(mreq->object, ap->a_m, ap->a_reqpage,
+		    round_page(ap->a_count) / PAGE_SIZE);
+		return (VM_PAGER_OK);
+	}
+
+	return (vnode_pager_generic_getpages(ap->a_vp, ap->a_m,
+	    ap->a_count, ap->a_reqpage));
+}
+
+/*
  * This is now called from local media FS's to operate against their
  * own vnodes if they fail to implement VOP_GETPAGES.
  */