+# LN_IB_SG_DMA_ADDRESS_EXISTS
+#
+# kernel 5.1 commit a163afc88556e099271a7b423295bc5176fcecce
+# IB/core: Remove ib_sg_dma_address() and ib_sg_dma_len()
+# ... when dma_ops existed (3.6) ib_sg_dma_address() was not trivial ...
+#
+AC_DEFUN([LN_IB_SG_DMA_ADDRESS_EXISTS], [
+tmp_flags="$EXTRA_KCFLAGS"
+EXTRA_KCFLAGS="-Werror"
+LB_CHECK_COMPILE([if ib_sg_dma_address wrapper exists],
+ib_sg_dma_address_test, [
+ #include <rdma/ib_verbs.h>
+],[
+ u64 x = ib_sg_dma_address(NULL, NULL);
+ x = x;
+ (void)x;
+],[
+ AC_DEFINE(HAVE_IB_SG_DMA_ADDRESS, 1,
+ [if ib_sg_dma_address wrapper exists])
+])
+EXTRA_KCFLAGS="$tmp_flags"
+]) # LN_IB_SG_DMA_ADDRESS_EXISTS
+
+#