[PATCH net-next] net: ethtool: pass genl_info to the ethnl parse_request operation

[Maxime Chevallier <maxime.chevallier@bootlin.com>]

The .parse_request() ethnl operation extracts the relevant attributes
from the netlink request to populate the private req_info.

By passing genl_info as a parameter to this callback, we can use
the GENL_REQ_ATTR_CHECK() macro to check for missing mandatory
parameters.

This macro has the advantage of returning a better error explanation
through the netlink_ext_ack struct.

Convert the eeprom ethnl code to this macro, as it's the only command
yet that has mandatory request parameters.

Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
---
 net/ethtool/eeprom.c  | 12 +++++++-----
 net/ethtool/netlink.c |  3 ++-
 net/ethtool/netlink.h |  1 +
 net/ethtool/pause.c   |  1 +
 net/ethtool/rss.c     |  4 +++-
 net/ethtool/stats.c   |  1 +
 net/ethtool/strset.c  |  1 +
 net/ethtool/tsinfo.c  |  4 +++-
 8 files changed, 19 insertions(+), 8 deletions(-)

diff --git a/net/ethtool/eeprom.c b/net/ethtool/eeprom.c
index caf1e41e676b..a557e3996c85 100644
--- a/net/ethtool/eeprom.c
+++ b/net/ethtool/eeprom.c
@@ -150,15 +150,17 @@ static int eeprom_prepare_data(const struct ethnl_req_info *req_base,
 	return ret;
 }
 
-static int eeprom_parse_request(struct ethnl_req_info *req_info, struct nlattr **tb,
+static int eeprom_parse_request(struct ethnl_req_info *req_info,
+				const struct genl_info *info,
+				struct nlattr **tb,
 				struct netlink_ext_ack *extack)
 {
 	struct eeprom_req_info *request = MODULE_EEPROM_REQINFO(req_info);
 
-	if (!tb[ETHTOOL_A_MODULE_EEPROM_OFFSET] ||
-	    !tb[ETHTOOL_A_MODULE_EEPROM_LENGTH] ||
-	    !tb[ETHTOOL_A_MODULE_EEPROM_PAGE] ||
-	    !tb[ETHTOOL_A_MODULE_EEPROM_I2C_ADDRESS])
+	if (GENL_REQ_ATTR_CHECK(info, ETHTOOL_A_MODULE_EEPROM_OFFSET) ||
+	    GENL_REQ_ATTR_CHECK(info, ETHTOOL_A_MODULE_EEPROM_LENGTH) ||
+	    GENL_REQ_ATTR_CHECK(info, ETHTOOL_A_MODULE_EEPROM_PAGE) ||
+	    GENL_REQ_ATTR_CHECK(info, ETHTOOL_A_MODULE_EEPROM_I2C_ADDRESS))
 		return -EINVAL;
 
 	request->i2c_address = nla_get_u8(tb[ETHTOOL_A_MODULE_EEPROM_I2C_ADDRESS]);
diff --git a/net/ethtool/netlink.c b/net/ethtool/netlink.c
index 14cb06ec5171..5046023a30b1 100644
--- a/net/ethtool/netlink.c
+++ b/net/ethtool/netlink.c
@@ -462,7 +462,8 @@ static int ethnl_default_parse(struct ethnl_req_info *req_info,
 		return ret;
 
 	if (request_ops->parse_request) {
-		ret = request_ops->parse_request(req_info, tb, info->extack);
+		ret = request_ops->parse_request(req_info, info, tb,
+						 info->extack);
 		if (ret < 0)
 			goto err_dev;
 	}
diff --git a/net/ethtool/netlink.h b/net/ethtool/netlink.h
index 89010eaa67df..aaf6f2468768 100644
--- a/net/ethtool/netlink.h
+++ b/net/ethtool/netlink.h
@@ -396,6 +396,7 @@ struct ethnl_request_ops {
 	u8			set_ntf_cmd;
 
 	int (*parse_request)(struct ethnl_req_info *req_info,
+			     const struct genl_info *info,
 			     struct nlattr **tb,
 			     struct netlink_ext_ack *extack);
 	int (*prepare_data)(const struct ethnl_req_info *req_info,
diff --git a/net/ethtool/pause.c b/net/ethtool/pause.c
index 29f812e935b6..ccaec8e878b2 100644
--- a/net/ethtool/pause.c
+++ b/net/ethtool/pause.c
@@ -28,6 +28,7 @@ const struct nla_policy ethnl_pause_get_policy[] = {
 };
 
 static int pause_parse_request(struct ethnl_req_info *req_base,
+			       const struct genl_info *info,
 			       struct nlattr **tb,
 			       struct netlink_ext_ack *extack)
 {
diff --git a/net/ethtool/rss.c b/net/ethtool/rss.c
index 0f4e5cd2ac71..b6c9b89ff6fb 100644
--- a/net/ethtool/rss.c
+++ b/net/ethtool/rss.c
@@ -66,7 +66,9 @@ const struct nla_policy ethnl_rss_get_policy[] = {
 };
 
 static int
-rss_parse_request(struct ethnl_req_info *req_info, struct nlattr **tb,
+rss_parse_request(struct ethnl_req_info *req_info,
+		  const struct genl_info *info,
+		  struct nlattr **tb,
 		  struct netlink_ext_ack *extack)
 {
 	struct rss_req_info *request = RSS_REQINFO(req_info);
diff --git a/net/ethtool/stats.c b/net/ethtool/stats.c
index 38136f19b2ec..9b0d8cb07675 100644
--- a/net/ethtool/stats.c
+++ b/net/ethtool/stats.c
@@ -99,6 +99,7 @@ const struct nla_policy ethnl_stats_get_policy[ETHTOOL_A_STATS_SRC + 1] = {
 };
 
 static int stats_parse_request(struct ethnl_req_info *req_base,
+			       const struct genl_info *info,
 			       struct nlattr **tb,
 			       struct netlink_ext_ack *extack)
 {
diff --git a/net/ethtool/strset.c b/net/ethtool/strset.c
index aa1e50c98f34..9271aba8255e 100644
--- a/net/ethtool/strset.c
+++ b/net/ethtool/strset.c
@@ -190,6 +190,7 @@ static const struct nla_policy strset_stringsets_policy[] = {
 };
 
 static int strset_parse_request(struct ethnl_req_info *req_base,
+				const struct genl_info *info,
 				struct nlattr **tb,
 				struct netlink_ext_ack *extack)
 {
diff --git a/net/ethtool/tsinfo.c b/net/ethtool/tsinfo.c
index 9aad62695dfb..a865f0fdd26b 100644
--- a/net/ethtool/tsinfo.c
+++ b/net/ethtool/tsinfo.c
@@ -70,7 +70,9 @@ int ts_parse_hwtst_provider(const struct nlattr *nest,
 }
 
 static int
-tsinfo_parse_request(struct ethnl_req_info *req_base, struct nlattr **tb,
+tsinfo_parse_request(struct ethnl_req_info *req_base,
+		     const struct genl_info *info,
+		     struct nlattr **tb,
 		     struct netlink_ext_ack *extack)
 {
 	struct tsinfo_req_info *req = TSINFO_REQINFO(req_base);
-- 
2.49.0