IPoIB/CM: Enable SRQ support on HCAs that support fewer than 16 SG entries
Some HCAs (such as ehca2) support SRQ, but only support fewer than 16 SG
entries for SRQs. Currently IPoIB/CM implicitly assumes all HCAs will
support 16 SG entries for SRQs (to handle a 64K MTU with 4K pages). This
patch removes that restriction by limiting the maximum MTU in connected
mode to what the maximum number of SRQ SG entries allows.
This patch addresses <https://bugs.openfabrics.org/show_bug.cgi?id=728>
Signed-off-by: Pradeep Satyanarayana <pradeeps@linux.vnet.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_main.c b/drivers/infiniband/ulp/ipoib/ipoib_main.c
index 3bfc2ef..d733045 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_main.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c
@@ -182,17 +182,20 @@
struct ipoib_dev_priv *priv = netdev_priv(dev);
/* dev->mtu > 2K ==> connected mode */
- if (ipoib_cm_admin_enabled(dev) && new_mtu <= IPOIB_CM_MTU) {
+ if (ipoib_cm_admin_enabled(dev)) {
+ if (new_mtu > ipoib_cm_max_mtu(dev))
+ return -EINVAL;
+
if (new_mtu > priv->mcast_mtu)
ipoib_warn(priv, "mtu > %d will cause multicast packet drops.\n",
priv->mcast_mtu);
+
dev->mtu = new_mtu;
return 0;
}
- if (new_mtu > IPOIB_PACKET_SIZE - IPOIB_ENCAP_LEN) {
+ if (new_mtu > IPOIB_PACKET_SIZE - IPOIB_ENCAP_LEN)
return -EINVAL;
- }
priv->admin_mtu = new_mtu;