Index: sys/vm/vm_object.c
===================================================================
--- sys/vm/vm_object.c
+++ sys/vm/vm_object.c
@@ -1000,7 +1000,7 @@
 
 static int
 vm_object_page_clean_flush(struct pctrie_iter *pages, vm_page_t p,
-    int pagerflags, int flags, boolean_t *allclean, boolean_t *eio)
+    int pagerflags, int flags, boolean_t *allclean, bool *eio)
 {
 	vm_page_t ma[vm_pageout_page_count];
 	int count, runlen;
@@ -1020,8 +1020,7 @@
 		}
 	}
 
-	vm_pageout_flush(ma, count, pagerflags, 0, &runlen, eio);
-	return (runlen);
+	return (vm_pageout_flush(ma, count, pagerflags, eio));
 }
 
 /*
@@ -1054,7 +1053,8 @@
 	vm_page_t np, p;
 	vm_pindex_t pi, tend, tstart;
 	int curgeneration, n, pagerflags;
-	boolean_t eio, res, allclean;
+	boolean_t res, allclean;
+	bool eio;
 
 	VM_OBJECT_ASSERT_WLOCKED(object);
 
Index: sys/vm/vm_pageout.h
===================================================================
--- sys/vm/vm_pageout.h
+++ sys/vm/vm_pageout.h
@@ -100,7 +100,7 @@
 void vm_wait_min(void);
 void vm_wait_severe(void);
 
-int vm_pageout_flush(vm_page_t *, int, int, int, int *, boolean_t *);
+int vm_pageout_flush(vm_page_t *, int count, int flags, bool *eio);
 void vm_pageout_oom(int shortage);
 
 #endif /* _KERNEL */
Index: sys/vm/vm_pageout.c
===================================================================
--- sys/vm/vm_pageout.c
+++ sys/vm/vm_pageout.c
@@ -438,7 +438,7 @@
 	}
 
 	return (vm_pageout_flush(&mc[page_base], pageout_count,
-	    VM_PAGER_PUT_NOREUSE, 0, NULL, NULL));
+	    VM_PAGER_PUT_NOREUSE, NULL));
 }
 
 /*
@@ -450,19 +450,19 @@
  *	the parent to do more sophisticated things we may have to change
  *	the ordering.
  *
- *	Returned runlen is the count of pages between mreq and first
- *	page after mreq with status VM_PAGER_AGAIN.
- *	*eio is set to TRUE if pager returned VM_PAGER_ERROR or VM_PAGER_FAIL
- *	for any page in runlen set.
+ *	If eio is not NULL, returns the count of pages between 0 and first page
+ *	with status VM_PAGER_AGAIN.  *eio is set to TRUE if pager returned
+ *	VM_PAGER_ERROR or VM_PAGER_FAIL for any page in that set.
+ *
+ *	Otherwise, returns the number of paged-out pages.
  */
 int
-vm_pageout_flush(vm_page_t *mc, int count, int flags, int mreq, int *prunlen,
-    boolean_t *eio)
+vm_pageout_flush(vm_page_t *mc, int count, int flags, bool *eio)
 {
 	vm_object_t object = mc[0]->object;
 	int pageout_status[count];
 	int numpagedout = 0;
-	int i, runlen;
+	int i;
 
 	VM_OBJECT_ASSERT_WLOCKED(object);
 
@@ -488,9 +488,8 @@
 
 	vm_pager_put_pages(object, mc, count, flags, pageout_status);
 
-	runlen = count - mreq;
 	if (eio != NULL)
-		*eio = FALSE;
+		*eio = false;
 	for (i = 0; i < count; i++) {
 		vm_page_t mt = mc[i];
 
@@ -540,12 +539,11 @@
 				numpagedout++;
 			} else
 				vm_page_activate(mt);
-			if (eio != NULL && i >= mreq && i - mreq < runlen)
-				*eio = TRUE;
+			if (eio != NULL)
+				*eio = true;
 			break;
 		case VM_PAGER_AGAIN:
-			if (i >= mreq && i - mreq < runlen)
-				runlen = i - mreq;
+			count = i;
 			break;
 		}
 
@@ -560,8 +558,8 @@
 			vm_page_sunbusy(mt);
 		}
 	}
-	if (prunlen != NULL)
-		*prunlen = runlen;
+	if (eio != NULL)
+		return (count);
 	return (numpagedout);
 }