[Devel] [PATCH RHEL9 COMMIT] Revert "Revert "ms/net: macsec: report real_dev features when HW offloading is enabled""

[Konstantin Khorenko]

The commit is pushed to "branch-rh9-5.14.vz9.1.x-ovz" and will appear at https://src.openvz.org/scm/ovz/vzkernel.git
after rh9-5.14.0-4.vz9.10.21
------>
commit 56c632876072d07ac9a67aa26b010fe42b860ee0
Author: Konstantin Khorenko <khorenko at virtuozzo.com>
Date:   Wed Oct 27 19:19:38 2021 +0300

    Revert "Revert "ms/net: macsec: report real_dev features when HW offloading is enabled""
    
    This reverts commit 040a3573b2d3904a5c546d4bf3dd6e068c6d6945.
    
    It's time to go home in a time machine.
    
    https://jira.sw.ru/browse/PSBM-134132
    
    Signed-off-by: Konstantin Khorenko <khorenko at virtuozzo.com>
---
 drivers/net/macsec.c | 27 +++++++++++++++++++++++----
 1 file changed, 23 insertions(+), 4 deletions(-)

diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c
index 6c0e5a0d32c7..93dc48b9b4f2 100644
--- a/drivers/net/macsec.c
+++ b/drivers/net/macsec.c
@@ -2644,6 +2644,11 @@ static int macsec_upd_offload(struct sk_buff *skb, struct genl_info *info)
 	if (ret)
 		goto rollback;
 
+	/* Force features update, since they are different for SW MACSec and
+	 * HW offloading cases.
+	 */
+	netdev_update_features(dev);
+
 	rtnl_unlock();
 	return 0;
 
@@ -3411,9 +3416,16 @@ static netdev_tx_t macsec_start_xmit(struct sk_buff *skb,
 	return ret;
 }
 
-#define MACSEC_FEATURES \
+#define SW_MACSEC_FEATURES \
 	(NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST)
 
+/* If h/w offloading is enabled, use real device features save for
+ *   VLAN_FEATURES - they require additional ops
+ *   HW_MACSEC - no reason to report it
+ */
+#define REAL_DEV_FEATURES(dev) \
+	((dev)->features & ~(NETIF_F_VLAN_FEATURES | NETIF_F_HW_MACSEC))
+
 static int macsec_dev_init(struct net_device *dev)
 {
 	struct macsec_dev *macsec = macsec_priv(dev);
@@ -3430,8 +3442,12 @@ static int macsec_dev_init(struct net_device *dev)
 		return err;
 	}
 
-	dev->features = real_dev->features & MACSEC_FEATURES;
-	dev->features |= NETIF_F_LLTX | NETIF_F_GSO_SOFTWARE;
+	if (macsec_is_offloaded(macsec)) {
+		dev->features = REAL_DEV_FEATURES(real_dev);
+	} else {
+		dev->features = real_dev->features & SW_MACSEC_FEATURES;
+		dev->features |= NETIF_F_LLTX | NETIF_F_GSO_SOFTWARE;
+	}
 
 	dev->needed_headroom = real_dev->needed_headroom +
 			       MACSEC_NEEDED_HEADROOM;
@@ -3460,7 +3476,10 @@ static netdev_features_t macsec_fix_features(struct net_device *dev,
 	struct macsec_dev *macsec = macsec_priv(dev);
 	struct net_device *real_dev = macsec->real_dev;
 
-	features &= (real_dev->features & MACSEC_FEATURES) |
+	if (macsec_is_offloaded(macsec))
+		return REAL_DEV_FEATURES(real_dev);
+
+	features &= (real_dev->features & SW_MACSEC_FEATURES) |
 		    NETIF_F_GSO_SOFTWARE | NETIF_F_SOFT_FEATURES;
 	features |= NETIF_F_LLTX;