From dfa279f9568b934ec1126d8a6302b23a84046ab9 Mon Sep 17 00:00:00 2001
From: "Christopher J. Morrone" <morrone2@llnl.gov>
Date: Wed, 24 Aug 2016 16:35:44 -0700
Subject: [PATCH] LU-8540 o2iblnd: Add support for 5arg ib_map_mr_sg()

Starting in kernel v4.7, ib_map_mr_sg() takes five arguments
rather than four.  It added an "sg_offset_p" offset pointer
argument.

RHEL7.3 also contains this change.

Change-Id: Ie63c992421bdf4ca195cf55152e6dfed9cf40e1d
Signed-off-by: Christopher J. Morrone <morrone2@llnl.gov>
Reviewed-on: http://review.whamcloud.com/22126
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Bob Glossman <bob.glossman@intel.com>
Reviewed-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-by: Dmitry Eremin <dmitry.eremin@intel.com>
Reviewed-by: Li Dongyang <dongyang.li@anu.edu.au>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
---
 lnet/autoconf/lustre-lnet.m4 | 27 +++++++++++++++++++++++++--
 lnet/klnds/o2iblnd/o2iblnd.c |  5 +++++
 2 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/lnet/autoconf/lustre-lnet.m4 b/lnet/autoconf/lustre-lnet.m4
index 47a4ff1..a1fdb5e 100644
--- a/lnet/autoconf/lustre-lnet.m4
+++ b/lnet/autoconf/lustre-lnet.m4
@@ -453,8 +453,8 @@ AS_IF([test $ENABLEO2IB != "no"], [
 	])
 
 	# new fast registration API introduced in 4.4
-	LB_CHECK_COMPILE([if 'ib_map_mr_sg' exists],
-	ib_map_mr_sg, [
+	LB_CHECK_COMPILE([if 4arg 'ib_map_mr_sg' exists],
+	ib_map_mr_sg_4args, [
 		#ifdef HAVE_COMPAT_RDMA
 		#undef PACKAGE_NAME
 		#undef PACKAGE_TARNAME
@@ -472,6 +472,29 @@ AS_IF([test $ENABLEO2IB != "no"], [
 			[ib_map_mr_sg exists])
 	])
 
+	# ib_map_mr_sg changes from 4 to 5 args (adding sg_offset_p)
+	# in kernel 4.7 (and RHEL 7.3)
+	LB_CHECK_COMPILE([if 5arg 'ib_map_mr_sg' exists],
+	ib_map_mr_sg_5args, [
+		#ifdef HAVE_COMPAT_RDMA
+		#undef PACKAGE_NAME
+		#undef PACKAGE_TARNAME
+		#undef PACKAGE_VERSION
+		#undef PACKAGE_STRING
+		#undef PACKAGE_BUGREPORT
+		#undef PACKAGE_URL
+		#include <linux/compat-2.6.h>
+		#endif
+		#include <rdma/ib_verbs.h>
+	],[
+		ib_map_mr_sg(NULL, NULL, 0, NULL, 0);
+	],[
+		AC_DEFINE(HAVE_IB_MAP_MR_SG, 1,
+			[ib_map_mr_sg exists])
+		AC_DEFINE(HAVE_IB_MAP_MR_SG_5ARGS, 1,
+			[ib_map_mr_sg has 5 arguments])
+	])
+
 	# ib_query_device() removed in 4.5
 	LB_CHECK_COMPILE([if 'struct ib_device' has member 'attrs'],
 	ib_device.attrs, [
diff --git a/lnet/klnds/o2iblnd/o2iblnd.c b/lnet/klnds/o2iblnd/o2iblnd.c
index aeecb30..9c6b8d5 100644
--- a/lnet/klnds/o2iblnd/o2iblnd.c
+++ b/lnet/klnds/o2iblnd/o2iblnd.c
@@ -1877,8 +1877,13 @@ again:
 				}
 
 #ifdef HAVE_IB_MAP_MR_SG
+#ifdef HAVE_IB_MAP_MR_SG_5ARGS
+				n = ib_map_mr_sg(mr, tx->tx_frags,
+						 tx->tx_nfrags, NULL, PAGE_SIZE);
+#else
 				n = ib_map_mr_sg(mr, tx->tx_frags,
 						 tx->tx_nfrags, PAGE_SIZE);
+#endif
 				if (unlikely(n != tx->tx_nfrags)) {
 					CERROR("Failed to map mr %d/%d "
 					       "elements\n", n, tx->tx_nfrags);
-- 
1.8.3.1