[PATCH v2] eal: choose IOVA mode according to compilation flags

[Viacheslav Ovsiienko <viacheslavo@nvidia.com>]

The DPDK can be compiled to be run in IOVA VA mode with
'enable_iova_as_pa=false' meson option. If there is no
explicit EAL --iova-mode parameter specified in the command
line the rte_eal_init() tried to deduce VA or PA mode without
taking into account the above mentioned compile time option,
resulting into initialization failure.

Signed-off-by: Viacheslav Ovsiienko <viacheslavo@nvidia.com>
---
 lib/eal/linux/eal.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/lib/eal/linux/eal.c b/lib/eal/linux/eal.c
index ae323cd492..9856ec9d12 100644
--- a/lib/eal/linux/eal.c
+++ b/lib/eal/linux/eal.c
@@ -1081,7 +1081,10 @@ rte_eal_init(int argc, char **argv)
 		if (iova_mode == RTE_IOVA_DC) {
 			RTE_LOG(DEBUG, EAL, "Buses did not request a specific IOVA mode.\n");
 
-			if (!phys_addrs) {
+			if (!RTE_IOVA_IN_MBUF) {
+				iova_mode = RTE_IOVA_VA;
+				RTE_LOG(DEBUG, EAL, "IOVA as VA mode is forced by build option.\n");
+			} else if (!phys_addrs) {
 				/* if we have no access to physical addresses,
 				 * pick IOVA as VA mode.
 				 */
-- 
2.18.1