devlink: Support querying hardware address of port function

Add support to query the hardware address of function represented
by devlink port function.

Example of a PCI VF port which supports a port function:
$ devlink port show pci/0000:06:00.0/2
pci/0000:06:00.0/2: type eth netdev enp6s0pf0vf1 flavour pcivf pfnum 0 vfnum 1
  function:
    hw_addr 00:11:22:33:44:66

$ devlink port show pci/0000:06:00.0/2 -jp
{
    "port": {
        "pci/0000:06:00.0/2": {
            "type": "eth",
            "netdev": "enp6s0pf0vf1",
            "flavour": "pcivf",
            "pfnum": 0,
            "vfnum": 1,
            "function": {
                "hw_addr": "00:11:22:33:44:66"
            }
        }
    }
}

Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David Ahern <dsahern@kernel.org>

diff --git a/devlink/devlink.c b/devlink/devlink.c
index b7699f301c6d3d6a3e62a525ba58eda9946d71d2..16fc834e049686383ec3c70db73b3ffa8dfb4829 100644 (file)
--- a/devlink/devlink.c
+++ b/devlink/devlink.c
@@ -26,6 +26,7 @@
 #include <libmnl/libmnl.h>
 #include <netinet/ether.h>
 #include <sys/types.h>
+#include <rt_names.h>
 
 #include "SNAPSHOT.h"
 #include "list.h"
@@ -708,6 +709,30 @@ static int attr_stats_cb(const struct nlattr *attr, void *data)
        return MNL_CB_OK;
 }
 
+static const enum mnl_attr_data_type
+devlink_function_policy[DEVLINK_PORT_FUNCTION_ATTR_MAX + 1] = {
+       [DEVLINK_PORT_FUNCTION_ATTR_HW_ADDR ] = MNL_TYPE_BINARY,
+};
+
+static int function_attr_cb(const struct nlattr *attr, void *data)
+{
+       const struct nlattr **tb = data;
+       int type;
+
+       /* Allow the tool to work on top of newer kernels that might contain
+        * more attributes.
+        */
+       if (mnl_attr_type_valid(attr, DEVLINK_PORT_FUNCTION_ATTR_MAX) < 0)
+               return MNL_CB_OK;
+
+       type = mnl_attr_get_type(attr);
+       if (mnl_attr_validate(attr, devlink_function_policy[type]) < 0)
+               return MNL_CB_ERROR;
+
+       tb[type] = attr;
+       return MNL_CB_OK;
+}
+
 static int ifname_map_cb(const struct nlmsghdr *nlh, void *data)
 {
        struct nlattr *tb[DEVLINK_ATTR_MAX + 1] = {};
@@ -3243,6 +3268,37 @@ static void pr_out_port_pfvf_num(struct dl *dl, struct nlattr **tb)
        }
 }
 
+static void pr_out_port_function(struct dl *dl, struct nlattr **tb_port)
+{
+       struct nlattr *tb[DEVLINK_PORT_FUNCTION_ATTR_MAX + 1] = {};
+       unsigned char *data;
+       SPRINT_BUF(hw_addr);
+       uint32_t len;
+       int err;
+
+       if (!tb_port[DEVLINK_ATTR_PORT_FUNCTION])
+               return;
+
+       err = mnl_attr_parse_nested(tb_port[DEVLINK_ATTR_PORT_FUNCTION],
+                                   function_attr_cb, tb);
+       if (err != MNL_CB_OK)
+               return;
+
+       if (!tb[DEVLINK_PORT_FUNCTION_ATTR_HW_ADDR])
+               return;
+
+       len = mnl_attr_get_payload_len(tb[DEVLINK_PORT_FUNCTION_ATTR_HW_ADDR]);
+       data = mnl_attr_get_payload(tb[DEVLINK_PORT_FUNCTION_ATTR_HW_ADDR]);
+
+       pr_out_object_start(dl, "function");
+       check_indent_newline(dl);
+       print_string(PRINT_ANY, "hw_addr", "hw_addr %s",
+                    ll_addr_n2a(data, len, 0, hw_addr, sizeof(hw_addr)));
+       if (!dl->json_output)
+               __pr_out_indent_dec();
+       pr_out_object_end(dl);
+}
+
 static void pr_out_port(struct dl *dl, struct nlattr **tb)
 {
        struct nlattr *pt_attr = tb[DEVLINK_ATTR_PORT_TYPE];
@@ -3296,6 +3352,7 @@ static void pr_out_port(struct dl *dl, struct nlattr **tb)
        if (tb[DEVLINK_ATTR_PORT_SPLIT_GROUP])
                print_uint(PRINT_ANY, "split_group", " split_group %u",
                           mnl_attr_get_u32(tb[DEVLINK_ATTR_PORT_SPLIT_GROUP]));
+       pr_out_port_function(dl, tb);
        pr_out_port_handle_end(dl);
 }