ionic: handle vlan id overflow

Add vlans to the existing rx_filter_sync mechanics currently
used for managing mac filters.

Older versions of our firmware had no enforced limits on the
number of vlans that the LIF could request, but requesting large
numbers of vlans caused issues in FW memory management, so an
arbitrary limit was added in the FW.  The FW now returns -ENOSPC
when it hits that limit, which the driver needs to handle.

Unfortunately, the FW doesn't advertise the vlan id limit,
as it does with mac filters, so the driver won't know the
limit until it bumps into it.  We'll grab the current vlan id
count and use that as the limit from there on and thus prevent
getting any more -ENOSPC errors.

Just as is done for the mac filters, the device puts the device
into promiscuous mode when -ENOSPC is seen for vlan ids, and
the driver will track the vlans that aren't synced to the FW.
When vlans are removed, the driver will retry the un-synced
vlans.  If all outstanding vlans are synced, the promiscuous
mode will be disabled.

Signed-off-by: Shannon Nelson <snelson@pensando.io>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 40 insertions, 1 deletions

diff --git a/drivers/net/ethernet/pensando/ionic/ionic_rx_filter.c b/drivers/net/ethernet/pensando/ionic/ionic_rx_filter.c
index 40a12b9df982..366f15794866 100644
--- a/drivers/net/ethernet/pensando/ionic/ionic_rx_filter.c
+++ b/drivers/net/ethernet/pensando/ionic/ionic_rx_filter.c
@@ -337,8 +337,16 @@ static int ionic_lif_filter_add(struct ionic_lif *lif,
 
 	/* Don't bother with the write to FW if we know there's no room,
 	 * we can try again on the next sync attempt.
+	 * Since the FW doesn't have a way to tell us the vlan limit,
+	 * we start max_vlans at 0 until we hit the ENOSPC error.
 	 */
 	switch (le16_to_cpu(ctx.cmd.rx_filter_add.match)) {
+	case IONIC_RX_FILTER_MATCH_VLAN:
+		netdev_dbg(lif->netdev, "%s: rx_filter add VLAN %d\n",
+			   __func__, ctx.cmd.rx_filter_add.vlan.vlan);
+		if (lif->max_vlans && lif->nvlans >= lif->max_vlans)
+			err = -ENOSPC;
+		break;
 	case IONIC_RX_FILTER_MATCH_MAC:
 		netdev_dbg(lif->netdev, "%s: rx_filter add ADDR %pM\n",
 			   __func__, ctx.cmd.rx_filter_add.mac.addr);
@@ -368,13 +376,19 @@ static int ionic_lif_filter_add(struct ionic_lif *lif,
 
 		spin_unlock_bh(&lif->rx_filters.lock);
 
-		if (err == -ENOSPC)
+		if (err == -ENOSPC) {
+			if (le16_to_cpu(ctx.cmd.rx_filter_add.match) == IONIC_RX_FILTER_MATCH_VLAN)
+				lif->max_vlans = lif->nvlans;
 			return 0;
+		}
 
 		return err;
 	}
 
 	switch (le16_to_cpu(ctx.cmd.rx_filter_add.match)) {
+	case IONIC_RX_FILTER_MATCH_VLAN:
+		lif->nvlans++;
+		break;
 	case IONIC_RX_FILTER_MATCH_MAC:
 		if (is_multicast_ether_addr(ctx.cmd.rx_filter_add.mac.addr))
 			lif->nmcast++;
@@ -413,6 +427,16 @@ int ionic_lif_addr_add(struct ionic_lif *lif, const u8 *addr)
 	return ionic_lif_filter_add(lif, &ac);
 }
 
+int ionic_lif_vlan_add(struct ionic_lif *lif, const u16 vid)
+{
+	struct ionic_rx_filter_add_cmd ac = {
+		.match = cpu_to_le16(IONIC_RX_FILTER_MATCH_VLAN),
+		.vlan.vlan = cpu_to_le16(vid),
+	};
+
+	return ionic_lif_filter_add(lif, &ac);
+}
+
 static int ionic_lif_filter_del(struct ionic_lif *lif,
 				struct ionic_rx_filter_add_cmd *ac)
 {
@@ -435,6 +459,11 @@ static int ionic_lif_filter_del(struct ionic_lif *lif,
 	}
 
 	switch (le16_to_cpu(ac->match)) {
+	case IONIC_RX_FILTER_MATCH_VLAN:
+		netdev_dbg(lif->netdev, "%s: rx_filter del VLAN %d id %d\n",
+			   __func__, ac->vlan.vlan, f->filter_id);
+		lif->nvlans--;
+		break;
 	case IONIC_RX_FILTER_MATCH_MAC:
 		netdev_dbg(lif->netdev, "%s: rx_filter del ADDR %pM id %d\n",
 			   __func__, ac->mac.addr, f->filter_id);
@@ -471,6 +500,16 @@ int ionic_lif_addr_del(struct ionic_lif *lif, const u8 *addr)
 	return ionic_lif_filter_del(lif, &ac);
 }
 
+int ionic_lif_vlan_del(struct ionic_lif *lif, const u16 vid)
+{
+	struct ionic_rx_filter_add_cmd ac = {
+		.match = cpu_to_le16(IONIC_RX_FILTER_MATCH_VLAN),
+		.vlan.vlan = cpu_to_le16(vid),
+	};
+
+	return ionic_lif_filter_del(lif, &ac);
+}
+
 struct sync_item {
 	struct list_head list;
 	struct ionic_rx_filter f;