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, 19 insertions, 16 deletions

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c
index dd722b0381e0..af55f19d5bba 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_ethtool.c
@@ -3107,35 +3107,37 @@ static void ixgbe_get_reta(struct ixgbe_adapter *adapter, u32 *indir)
 		indir[i] = adapter->rss_indir_tbl[i] & rss_m;
 }
 
-static int ixgbe_get_rxfh(struct net_device *netdev, u32 *indir, u8 *key,
-			  u8 *hfunc)
+static int ixgbe_get_rxfh(struct net_device *netdev,
+			  struct ethtool_rxfh_param *rxfh)
 {
 	struct ixgbe_adapter *adapter = netdev_priv(netdev);
 
-	if (hfunc)
-		*hfunc = ETH_RSS_HASH_TOP;
+	rxfh->hfunc = ETH_RSS_HASH_TOP;
 
-	if (indir)
-		ixgbe_get_reta(adapter, indir);
+	if (rxfh->indir)
+		ixgbe_get_reta(adapter, rxfh->indir);
 
-	if (key)
-		memcpy(key, adapter->rss_key, ixgbe_get_rxfh_key_size(netdev));
+	if (rxfh->key)
+		memcpy(rxfh->key, adapter->rss_key,
+		       ixgbe_get_rxfh_key_size(netdev));
 
 	return 0;
 }
 
-static int ixgbe_set_rxfh(struct net_device *netdev, const u32 *indir,
-			  const u8 *key, const u8 hfunc)
+static int ixgbe_set_rxfh(struct net_device *netdev,
+			  struct ethtool_rxfh_param *rxfh,
+			  struct netlink_ext_ack *extack)
 {
 	struct ixgbe_adapter *adapter = netdev_priv(netdev);
 	int i;
 	u32 reta_entries = ixgbe_rss_indir_tbl_entries(adapter);
 
-	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) {
 		int max_queues = min_t(int, adapter->num_rx_queues,
 				       ixgbe_rss_indir_tbl_max(adapter));
 
@@ -3146,18 +3148,19 @@ static int ixgbe_set_rxfh(struct net_device *netdev, const u32 *indir,
 
 		/* Verify user input. */
 		for (i = 0; i < reta_entries; i++)
-			if (indir[i] >= max_queues)
+			if (rxfh->indir[i] >= max_queues)
 				return -EINVAL;
 
 		for (i = 0; i < reta_entries; i++)
-			adapter->rss_indir_tbl[i] = indir[i];
+			adapter->rss_indir_tbl[i] = rxfh->indir[i];
 
 		ixgbe_store_reta(adapter);
 	}
 
 	/* Fill out the rss hash key */
-	if (key) {
-		memcpy(adapter->rss_key, key, ixgbe_get_rxfh_key_size(netdev));
+	if (rxfh->key) {
+		memcpy(adapter->rss_key, rxfh->key,
+		       ixgbe_get_rxfh_key_size(netdev));
 		ixgbe_store_key(adapter);
 	}