[PATCH net] net: txgbe: fix FDIR filter restore for VF rules

[Zhang Yunfei]

txgbe_fdir_filter_restore() reprograms every filter from
txgbe->fdir_filter_list after a reset. It extracts the ring part of
filter->action with ethtool_get_flow_spec_ring() and maps it onto a
PF rx ring, silently dropping the VF part of the cookie that
txgbe_add_ethtool_fdir_entry() stores there (input->action =
fsp->ring_cookie).

For a rule directed at a VF, restore therefore reprograms the filter
to the PF queue with the same ring index: after any down/up or
txgbe_reinit_locked(), traffic matching the rule is steered to the
PF instead of the VF.

Handle VF rules the same way txgbe_add_ethtool_fdir_entry() does:
validate vf against wx->num_vfs and ring against
wx->num_rx_queues_per_pool, and map the ring onto the absolute
queue index ((vf - 1) * wx->num_rx_queues_per_pool) + ring.

Fixes: 7a91722e0dd4 ("net: txgbe: Support the FDIR rules assigned to VFs")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Zhang Yunfei <zhangyunfei1@xxxxxxxxxx>
---
 drivers/net/ethernet/wangxun/txgbe/txgbe_fdir.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/wangxun/txgbe/txgbe_fdir.c b/drivers/net/ethernet/wangxun/txgbe/txgbe_fdir.c
index a84010828551..59a47532618c 100644
--- a/drivers/net/ethernet/wangxun/txgbe/txgbe_fdir.c
+++ b/drivers/net/ethernet/wangxun/txgbe/txgbe_fdir.c
@@ -591,15 +591,24 @@ static void txgbe_fdir_filter_restore(struct wx *wx)
 			queue = TXGBE_RDB_FDIR_DROP_QUEUE;
 		} else {
 			u32 ring = ethtool_get_flow_spec_ring(filter->action);
+			u8 vf = ethtool_get_flow_spec_ring_vf(filter->action);
 
-			if (ring >= wx->num_rx_queues) {
+			if (!vf && ring >= wx->num_rx_queues) {
 				wx_err(wx, "FDIR restore failed, ring:%u\n",
 				       ring);
 				continue;
+			} else if (vf && (vf > wx->num_vfs ||
+				  ring >= wx->num_rx_queues_per_pool)) {
+				wx_err(wx, "FDIR restore failed, vf:%u, ring:%u\n",
+				       vf, ring);
+				continue;
 			}
 
 			/* Map the ring onto the absolute queue index */
-			queue = wx->rx_ring[ring]->reg_idx;
+			if (!vf)
+				queue = wx->rx_ring[ring]->reg_idx;
+			else
+				queue = ((vf - 1) * wx->num_rx_queues_per_pool) + ring;
 		}
 
 		ret = txgbe_fdir_write_perfect_filter(wx,
-- 
2.25.1