net/smc: allow pnetid-less configuration

Without hardware pnetid support there must currently be a pnet
table configured to determine the IB device port to be used for SMC
RDMA traffic. This patch enables a setup without pnet table, if
the used handshake interface belongs already to a RoCE port.

Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/smc/smc_pnet.c b/net/smc/smc_pnet.c
index 25dfbe3..8d2f629 100644 (file)
--- a/net/smc/smc_pnet.c
+++ b/net/smc/smc_pnet.c
@@ -754,9 +754,47 @@ static int smc_pnet_find_ndev_pnetid_by_table(struct net_device *ndev,
        return rc;
 }
 
+/* if handshake network device belongs to a roce device, return its
+ * IB device and port
+ */
+static void smc_pnet_find_rdma_dev(struct net_device *netdev,
+                                  struct smc_ib_device **smcibdev,
+                                  u8 *ibport, unsigned short vlan_id, u8 gid[])
+{
+       struct smc_ib_device *ibdev;
+
+       spin_lock(&smc_ib_devices.lock);
+       list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
+               struct net_device *ndev;
+               int i;
+
+               for (i = 1; i <= SMC_MAX_PORTS; i++) {
+                       if (!rdma_is_port_valid(ibdev->ibdev, i))
+                               continue;
+                       if (!ibdev->ibdev->ops.get_netdev)
+                               continue;
+                       ndev = ibdev->ibdev->ops.get_netdev(ibdev->ibdev, i);
+                       if (!ndev)
+                               continue;
+                       dev_put(ndev);
+                       if (netdev == ndev &&
+                           smc_ib_port_active(ibdev, i) &&
+                           !smc_ib_determine_gid(ibdev, i, vlan_id, gid,
+                                                 NULL)) {
+                               *smcibdev = ibdev;
+                               *ibport = i;
+                               break;
+                       }
+               }
+       }
+       spin_unlock(&smc_ib_devices.lock);
+}
+
 /* Determine the corresponding IB device port based on the hardware PNETID.
  * Searching stops at the first matching active IB device port with vlan_id
  * configured.
+ * If nothing found, check pnetid table.
+ * If nothing found, try to use handshake device
  */
 static void smc_pnet_find_roce_by_pnetid(struct net_device *ndev,
                                         struct smc_ib_device **smcibdev,
@@ -770,8 +808,10 @@ static void smc_pnet_find_roce_by_pnetid(struct net_device *ndev,
        ndev = pnet_find_base_ndev(ndev);
        if (smc_pnetid_by_dev_port(ndev->dev.parent, ndev->dev_port,
                                   ndev_pnetid) &&
-           smc_pnet_find_ndev_pnetid_by_table(ndev, ndev_pnetid))
+           smc_pnet_find_ndev_pnetid_by_table(ndev, ndev_pnetid)) {
+               smc_pnet_find_rdma_dev(ndev, smcibdev, ibport, vlan_id, gid);
                return; /* pnetid could not be determined */
+       }
 
        spin_lock(&smc_ib_devices.lock);
        list_for_each_entry(ibdev, &smc_ib_devices.list, list) {