net: ethtool: pass a pointer to parameters to get/set_rxfh ethtool ops

The get/set_rxfh ethtool ops currently takes the rxfh (RSS) parameters
as direct function arguments. This will force us to change the API (and
all drivers' functions) every time some new parameters are added.

This is part 1/2 of the fix, as suggested in [1]:

- First simplify the code by always providing a pointer to all params
   (indir, key and func); the fact that some of them may be NULL seems
   like a weird historic thing or a premature optimization.
   It will simplify the drivers if all pointers are always present.

 - Then make the functions take a dev pointer, and a pointer to a
   single struct wrapping all arguments. The set_* should also take
   an extack.

Link: https://lore.kernel.org/netdev/20231121152906.2dd5f487@kernel.org/ [1]
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Suggested-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Ahmed Zaki <ahmed.zaki@intel.com>
Link: https://lore.kernel.org/r/20231213003321.605376-2-ahmed.zaki@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 16 insertions, 15 deletions

diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_ethtool.c b/drivers/net/ethernet/aquantia/atlantic/aq_ethtool.c
index ac4ea93bd8dd..18a6c8d99fa0 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_ethtool.c
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_ethtool.c
@@ -447,8 +447,8 @@ static u32 aq_ethtool_get_rss_key_size(struct net_device *ndev)
 	return sizeof(cfg->aq_rss.hash_secret_key);
 }
 
-static int aq_ethtool_get_rss(struct net_device *ndev, u32 *indir, u8 *key,
-			      u8 *hfunc)
+static int aq_ethtool_get_rss(struct net_device *ndev,
+			      struct ethtool_rxfh_param *rxfh)
 {
 	struct aq_nic_s *aq_nic = netdev_priv(ndev);
 	struct aq_nic_cfg_s *cfg;
@@ -456,21 +456,21 @@ static int aq_ethtool_get_rss(struct net_device *ndev, u32 *indir, u8 *key,
 
 	cfg = aq_nic_get_cfg(aq_nic);
 
-	if (hfunc)
-		*hfunc = ETH_RSS_HASH_TOP; /* Toeplitz */
-	if (indir) {
+	rxfh->hfunc = ETH_RSS_HASH_TOP; /* Toeplitz */
+	if (rxfh->indir) {
 		for (i = 0; i < AQ_CFG_RSS_INDIRECTION_TABLE_MAX; i++)
-			indir[i] = cfg->aq_rss.indirection_table[i];
+			rxfh->indir[i] = cfg->aq_rss.indirection_table[i];
 	}
-	if (key)
-		memcpy(key, cfg->aq_rss.hash_secret_key,
+	if (rxfh->key)
+		memcpy(rxfh->key, cfg->aq_rss.hash_secret_key,
 		       sizeof(cfg->aq_rss.hash_secret_key));
 
 	return 0;
 }
 
-static int aq_ethtool_set_rss(struct net_device *netdev, const u32 *indir,
-			      const u8 *key, const u8 hfunc)
+static int aq_ethtool_set_rss(struct net_device *netdev,
+			      struct ethtool_rxfh_param *rxfh,
+			      struct netlink_ext_ack *extack)
 {
 	struct aq_nic_s *aq_nic = netdev_priv(netdev);
 	struct aq_nic_cfg_s *cfg;
@@ -482,16 +482,17 @@ static int aq_ethtool_set_rss(struct net_device *netdev, const u32 *indir,
 	rss_entries = cfg->aq_rss.indirection_table_size;
 
 	/* We do not allow change in unsupported parameters */
-	if (hfunc != ETH_RSS_HASH_NO_CHANGE && hfunc != ETH_RSS_HASH_TOP)
+	if (rxfh->hfunc != ETH_RSS_HASH_NO_CHANGE &&
+	    rxfh->hfunc != ETH_RSS_HASH_TOP)
 		return -EOPNOTSUPP;
 	/* Fill out the redirection table */
-	if (indir)
+	if (rxfh->indir)
 		for (i = 0; i < rss_entries; i++)
-			cfg->aq_rss.indirection_table[i] = indir[i];
+			cfg->aq_rss.indirection_table[i] = rxfh->indir[i];
 
 	/* Fill out the rss hash key */
-	if (key) {
-		memcpy(cfg->aq_rss.hash_secret_key, key,
+	if (rxfh->key) {
+		memcpy(cfg->aq_rss.hash_secret_key, rxfh->key,
 		       sizeof(cfg->aq_rss.hash_secret_key));
 		err = aq_nic->aq_hw_ops->hw_rss_hash_set(aq_nic->aq_hw,
 			&cfg->aq_rss);