osd: do_sparse_read(): On Checksum mismatch try to repair

Fixes: http://tracker.ceph.com/issues/24875

Signed-off-by: David Zafman <dzafman@redhat.com>
(cherry picked from commit 929f78a)

src/osd/PrimaryLogPG.cc

@@ -5596,8 +5596,10 @@ int PrimaryLogPG::do_sparse_read(OpContext *ctx, OSDOp& osd_op) {
           << " full-object read crc 0x" << crc
           << " != expected 0x" << oi.data_digest
           << std::dec << " on " << soid;
-        // FIXME fall back to replica or something?
-        return -EIO;
+        r = rep_repair_primary_object(soid, ctx->op);
+	if (r < 0) {
+	  return r;
+	}
       }
     }