[dpdk-dev] [PATCH v2 1/3] eal/linux: select iova-mode va with no-huge option

[David Wilder]

If --no-huge is set and iova-mode has not been specified force VA mode.
If --no-huge and --iova-mode=PA is requested error out as this is
an impossible configuration.

Signed-off-by: David Wilder <dwil...@us.ibm.com>
---
 lib/librte_eal/linux/eal/eal.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/lib/librte_eal/linux/eal/eal.c b/lib/librte_eal/linux/eal/eal.c
index 9530ee55f..d3a0a1731 100644
--- a/lib/librte_eal/linux/eal/eal.c
+++ b/lib/librte_eal/linux/eal/eal.c
@@ -1062,9 +1062,16 @@ rte_eal_init(int argc, char **argv)
 
        /* if no EAL option "--iova-mode=<pa|va>", use bus IOVA scheme */
        if (internal_config.iova_mode == RTE_IOVA_DC) {
+
                /* autodetect the IOVA mapping mode */
                enum rte_iova_mode iova_mode = rte_bus_get_iommu_class();
 
+               if (iova_mode == RTE_IOVA_PA && !rte_eal_has_hugepages()) {
+                       iova_mode = RTE_IOVA_VA;
+                       RTE_LOG(WARNING, EAL, "Some buses want 'PA' but forcing 
'VA' because --no-huge is requested.\n");
+                       RTE_LOG(WARNING, EAL, "Not all buses may be able to 
initialize.\n");
+               }
+
                if (iova_mode == RTE_IOVA_DC) {
                        RTE_LOG(DEBUG, EAL, "Buses did not request a specific 
IOVA mode.\n");
 
@@ -1111,6 +1118,13 @@ rte_eal_init(int argc, char **argv)
                        internal_config.iova_mode;
        }
 
+       if (rte_eal_iova_mode() == RTE_IOVA_PA &&
+           rte_eal_has_hugepages() == 0) {
+               rte_eal_init_alert("Cannot use IOVA as 'PA' with --no-huge");
+               rte_errno = EINVAL;
+               return -1;
+       }
+
        if (rte_eal_iova_mode() == RTE_IOVA_PA && !phys_addrs) {
                rte_eal_init_alert("Cannot use IOVA as 'PA' since physical 
addresses are not available");
                rte_errno = EINVAL;
-- 
2.25.0