net/ethtool/linkstate.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2
   3 #include "netlink.h"
   4 #include "common.h"
   5
   6 struct linkstate_req_info {
   7         struct ethnl_req_info           base;
   8 };
   9
  10 struct linkstate_reply_data {
  11         struct ethnl_reply_data         base;
  12         int                             link;
  13 };
  14
  15 #define LINKSTATE_REPDATA(__reply_base) \
  16         container_of(__reply_base, struct linkstate_reply_data, base)
  17
  18 static const struct nla_policy
  19 linkstate_get_policy[ETHTOOL_A_LINKSTATE_MAX + 1] = {
  20         [ETHTOOL_A_LINKSTATE_UNSPEC]            = { .type = NLA_REJECT },
  21         [ETHTOOL_A_LINKSTATE_HEADER]            = { .type = NLA_NESTED },
  22         [ETHTOOL_A_LINKSTATE_LINK]              = { .type = NLA_REJECT },
  23 };
  24
  25 static int linkstate_prepare_data(const struct ethnl_req_info *req_base,
  26                                   struct ethnl_reply_data *reply_base,
  27                                   struct genl_info *info)
  28 {
  29         struct linkstate_reply_data *data = LINKSTATE_REPDATA(reply_base);
  30         struct net_device *dev = reply_base->dev;
  31         int ret;
  32
  33         ret = ethnl_ops_begin(dev);
  34         if (ret < 0)
  35                 return ret;
  36         data->link = __ethtool_get_link(dev);
  37         ethnl_ops_complete(dev);
  38
  39         return 0;
  40 }
  41
  42 static int linkstate_reply_size(const struct ethnl_req_info *req_base,
  43                                 const struct ethnl_reply_data *reply_base)
  44 {
  45         return nla_total_size(sizeof(u8)) /* LINKSTATE_LINK */
  46                 + 0;
  47 }
  48
  49 static int linkstate_fill_reply(struct sk_buff *skb,
  50                                 const struct ethnl_req_info *req_base,
  51                                 const struct ethnl_reply_data *reply_base)
  52 {
  53         struct linkstate_reply_data *data = LINKSTATE_REPDATA(reply_base);
  54
  55         if (data->link >= 0 &&
  56             nla_put_u8(skb, ETHTOOL_A_LINKSTATE_LINK, !!data->link))
  57                 return -EMSGSIZE;
  58
  59         return 0;
  60 }
  61
  62 const struct ethnl_request_ops ethnl_linkstate_request_ops = {
  63         .request_cmd            = ETHTOOL_MSG_LINKSTATE_GET,
  64         .reply_cmd              = ETHTOOL_MSG_LINKSTATE_GET_REPLY,
  65         .hdr_attr               = ETHTOOL_A_LINKSTATE_HEADER,
  66         .max_attr               = ETHTOOL_A_LINKSTATE_MAX,
  67         .req_info_size          = sizeof(struct linkstate_req_info),
  68         .reply_data_size        = sizeof(struct linkstate_reply_data),
  69         .request_policy         = linkstate_get_policy,
  70
  71         .prepare_data           = linkstate_prepare_data,
  72         .reply_size             = linkstate_reply_size,
  73         .fill_reply             = linkstate_fill_reply,
  74 };