Index: sys/geom/geom_dev.c
===================================================================
--- sys/geom/geom_dev.c
+++ sys/geom/geom_dev.c
@@ -634,19 +634,6 @@
 			error = EINVAL;
 			break;
 		}
-		if ((pp->mediasize > 0) && (offset >= pp->mediasize)) {
-			/*
-			 * Catch out-of-bounds requests here. The problem is
-			 * that due to historical GEOM I/O implementation
-			 * peculatities, g_delete_data() would always return
-			 * success for requests starting just the next byte
-			 * after providers media boundary. Condition check on
-			 * non-zero media size, since that condition would
-			 * (most likely) cause ENXIO instead.
-			 */
-			error = EIO;
-			break;
-		}
 		while (length > 0) {
 			chunk = length;
 			if (g_dev_del_max_sectors != 0 &&
Index: sys/geom/geom_io.c
===================================================================
--- sys/geom/geom_io.c
+++ sys/geom/geom_io.c
@@ -894,6 +894,8 @@
 	bp->bio_data = ptr;
 	g_io_request(bp, cp);
 	errorc = biowait(bp, "gread");
+	if (errorc == 0 && bp->bio_completed != length)
+		errorc = EIO;
 	if (error != NULL)
 		*error = errorc;
 	g_destroy_bio(bp);
@@ -948,6 +950,8 @@
 	bp->bio_data = ptr;
 	g_io_request(bp, cp);
 	error = biowait(bp, "gwrite");
+	if (error == 0 && bp->bio_completed != length)
+		error = EIO;
 	g_destroy_bio(bp);
 	return (error);
 }
@@ -979,6 +983,8 @@
 	bp->bio_data = NULL;
 	g_io_request(bp, cp);
 	error = biowait(bp, "gdelete");
+	if (error == 0 && bp->bio_completed != length)
+		error = EIO;
 	g_destroy_bio(bp);
 	return (error);
 }