rs->max_sectors =
min_not_zero(rs->max_sectors, q->max_sectors);
- /* FIXME: Device-Mapper on top of RAID-0 breaks because DM
- * currently doesn't honor MD's merge_bvec_fn routine.
- * In this case, we'll force DM to use PAGE_SIZE or
- * smaller I/O, just to be safe. A better fix is in the
- * works, but add this for the time being so it will at
- * least operate correctly.
+ /*
+ * Check if merge fn is supported.
+ * If not we'll force DM to use PAGE_SIZE or
+ * smaller I/O, just to be safe.
*/
- if (q->merge_bvec_fn)
+
+ if (q->merge_bvec_fn && !ti->type->merge)
rs->max_sectors =
min_not_zero(rs->max_sectors,
(unsigned int) (PAGE_SIZE >> 9));