ethtool: Allow network drivers to dump arbitrary EEPROM data

Define get_module_eeprom_by_page() ethtool callback and implement
netlink infrastructure.

get_module_eeprom_by_page() allows network drivers to dump a part of
module's EEPROM specified by page and bank numbers along with offset and
length. It is effectively a netlink replacement for get_module_info()
and get_module_eeprom() pair, which is needed due to emergence of
complex non-linear EEPROM layouts.

Signed-off-by: Vladyslav Tarasiuk <vladyslavt@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ethtool/netlink.h b/net/ethtool/netlink.h
index 785f7ee4..4305ac9 100644
--- a/net/ethtool/netlink.h
+++ b/net/ethtool/netlink.h
@@ -345,6 +345,7 @@ extern const struct ethnl_request_ops ethnl_pause_request_ops;
 extern const struct ethnl_request_ops ethnl_eee_request_ops;
 extern const struct ethnl_request_ops ethnl_tsinfo_request_ops;
 extern const struct ethnl_request_ops ethnl_fec_request_ops;
+extern const struct ethnl_request_ops ethnl_module_eeprom_request_ops;
 
 extern const struct nla_policy ethnl_header_policy[ETHTOOL_A_HEADER_FLAGS + 1];
 extern const struct nla_policy ethnl_header_policy_stats[ETHTOOL_A_HEADER_FLAGS + 1];
@@ -378,6 +379,7 @@ extern const struct nla_policy ethnl_cable_test_tdr_act_policy[ETHTOOL_A_CABLE_T
 extern const struct nla_policy ethnl_tunnel_info_get_policy[ETHTOOL_A_TUNNEL_INFO_HEADER + 1];
 extern const struct nla_policy ethnl_fec_get_policy[ETHTOOL_A_FEC_HEADER + 1];
 extern const struct nla_policy ethnl_fec_set_policy[ETHTOOL_A_FEC_AUTO + 1];
+extern const struct nla_policy ethnl_module_eeprom_get_policy[ETHTOOL_A_MODULE_EEPROM_DATA + 1];
 
 int ethnl_set_linkinfo(struct sk_buff *skb, struct genl_info *info);
 int ethnl_set_linkmodes(struct sk_buff *skb, struct genl_info *info);