[PATCH net-next v2 6/6] devlink: Use controller while building phys_port_name

[Parav Pandit]

From: Parav Pandit <pa...@nvidia.com>

Now that controller number attribute is available, use it when
building phsy_port_name for external controller ports.

An example devlink port and representor netdev name consist of controller
annotation for external controller with controller number = 1,
for a VF 1 of PF 0:

$ devlink port show pci/0000:06:00.0/2
pci/0000:06:00.0/2: type eth netdev ens2f0c1pf0vf1 flavour pcivf controller 1 
pfnum 0 vfnum 1 external true splittable false
  function:
    hw_addr 00:00:00:00:00:00

$ devlink port show pci/0000:06:00.0/2 -jp
{
    "port": {
        "pci/0000:06:00.0/2": {
            "type": "eth",
            "netdev": "ens2f0c1pf0vf1",
            "flavour": "pcivf",
            "controller": 1,
            "pfnum": 0,
            "vfnum": 1,
            "external": true,
            "splittable": false,
            "function": {
                "hw_addr": "00:00:00:00:00:00"
            }
        }
    }
}

Controller number annotation is skipped for non external controllers to
maintain backward compatibility.

Signed-off-by: Parav Pandit <pa...@nvidia.com>
Reviewed-by: Jiri Pirko <j...@nvidia.com>
---
Changelog:
v1->v2:
 - New patch
---
 net/core/devlink.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/net/core/devlink.c b/net/core/devlink.c
index 9cf5b118253b..91c12612f2b7 100644
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -7793,9 +7793,23 @@ static int __devlink_port_phys_port_name_get(struct 
devlink_port *devlink_port,
                WARN_ON(1);
                return -EINVAL;
        case DEVLINK_PORT_FLAVOUR_PCI_PF:
+               if (attrs->pci_pf.external) {
+                       n = snprintf(name, len, "c%u", 
attrs->pci_pf.controller);
+                       if (n >= len)
+                               return -EINVAL;
+                       len -= n;
+                       name += n;
+               }
                n = snprintf(name, len, "pf%u", attrs->pci_pf.pf);
                break;
        case DEVLINK_PORT_FLAVOUR_PCI_VF:
+               if (attrs->pci_vf.external) {
+                       n = snprintf(name, len, "c%u", 
attrs->pci_vf.controller);
+                       if (n >= len)
+                               return -EINVAL;
+                       len -= n;
+                       name += n;
+               }
                n = snprintf(name, len, "pf%uvf%u",
                             attrs->pci_vf.pf, attrs->pci_vf.vf);
                break;
-- 
2.26.2