Merge branch 'ethtool-allow-dumping-policies-to-user-space'

Jakub Kicinski says:

====================
ethtool: allow dumping policies to user space

This series wires up ethtool policies to ops, so they can be
dumped to user space for feature discovery.

First patch wires up GET commands, and second patch wires up SETs.

The policy tables are trimmed to save space and LoC.

Next - take care of linking up nested policies for the header
(which is the policy what we actually care about). And once header
policy is linked make sure that attribute range validation for flags
is done by policy, not a conditions in the code. New type of policy
is needed to validate masks (patch 6).

Netlink as always staying a step ahead of all the other kernel
API interfaces :)

v2:
 - merge patches 1 & 2 -> 1
 - add patch 3 & 5
 - remove .max_attr from struct ethnl_request_ops
====================

Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 7 insertions, 20 deletions

diff --git a/net/ethtool/pause.c b/net/ethtool/pause.c
index 1980aa7eb2b6..09998dc5c185 100644
--- a/net/ethtool/pause.c
+++ b/net/ethtool/pause.c
@@ -16,14 +16,9 @@ struct pause_reply_data {
 #define PAUSE_REPDATA(__reply_base) \
 	container_of(__reply_base, struct pause_reply_data, base)
 
-static const struct nla_policy
-pause_get_policy[ETHTOOL_A_PAUSE_MAX + 1] = {
-	[ETHTOOL_A_PAUSE_UNSPEC]		= { .type = NLA_REJECT },
-	[ETHTOOL_A_PAUSE_HEADER]		= { .type = NLA_NESTED },
-	[ETHTOOL_A_PAUSE_AUTONEG]		= { .type = NLA_REJECT },
-	[ETHTOOL_A_PAUSE_RX]			= { .type = NLA_REJECT },
-	[ETHTOOL_A_PAUSE_TX]			= { .type = NLA_REJECT },
-	[ETHTOOL_A_PAUSE_STATS]			= { .type = NLA_REJECT },
+const struct nla_policy ethnl_pause_get_policy[] = {
+	[ETHTOOL_A_PAUSE_HEADER]		=
+		NLA_POLICY_NESTED(ethnl_header_policy_stats),
 };
 
 static void ethtool_stats_init(u64 *stats, unsigned int n)
@@ -130,10 +125,8 @@ const struct ethnl_request_ops ethnl_pause_request_ops = {
 	.request_cmd		= ETHTOOL_MSG_PAUSE_GET,
 	.reply_cmd		= ETHTOOL_MSG_PAUSE_GET_REPLY,
 	.hdr_attr		= ETHTOOL_A_PAUSE_HEADER,
-	.max_attr		= ETHTOOL_A_PAUSE_MAX,
 	.req_info_size		= sizeof(struct pause_req_info),
 	.reply_data_size	= sizeof(struct pause_reply_data),
-	.request_policy		= pause_get_policy,
 
 	.prepare_data		= pause_prepare_data,
 	.reply_size		= pause_reply_size,
@@ -142,30 +135,24 @@ const struct ethnl_request_ops ethnl_pause_request_ops = {
 
 /* PAUSE_SET */
 
-static const struct nla_policy
-pause_set_policy[ETHTOOL_A_PAUSE_MAX + 1] = {
-	[ETHTOOL_A_PAUSE_UNSPEC]		= { .type = NLA_REJECT },
-	[ETHTOOL_A_PAUSE_HEADER]		= { .type = NLA_NESTED },
+const struct nla_policy ethnl_pause_set_policy[] = {
+	[ETHTOOL_A_PAUSE_HEADER]		=
+		NLA_POLICY_NESTED(ethnl_header_policy),
 	[ETHTOOL_A_PAUSE_AUTONEG]		= { .type = NLA_U8 },
 	[ETHTOOL_A_PAUSE_RX]			= { .type = NLA_U8 },
 	[ETHTOOL_A_PAUSE_TX]			= { .type = NLA_U8 },
-	[ETHTOOL_A_PAUSE_STATS]			= { .type = NLA_REJECT },
 };
 
 int ethnl_set_pause(struct sk_buff *skb, struct genl_info *info)
 {
-	struct nlattr *tb[ETHTOOL_A_PAUSE_MAX + 1];
 	struct ethtool_pauseparam params = {};
 	struct ethnl_req_info req_info = {};
+	struct nlattr **tb = info->attrs;
 	const struct ethtool_ops *ops;
 	struct net_device *dev;
 	bool mod = false;
 	int ret;
 
-	ret = nlmsg_parse(info->nlhdr, GENL_HDRLEN, tb, ETHTOOL_A_PAUSE_MAX,
-			  pause_set_policy, info->extack);
-	if (ret < 0)
-		return ret;
 	ret = ethnl_parse_header_dev_get(&req_info,
 					 tb[ETHTOOL_A_PAUSE_HEADER],
 					 genl_info_net(info), info->extack,