bnxt_en: Add new BNXT_FLTR_INSERTED flag to bnxt_filter_base struct.

Change the unused flag to BNXT_FLTR_INSERTED.  To prepare for multiple
pathways that an ntuple filter can be deleted, we add this flag.  These
filter structures can be retreived from the RCU hash table but only
the caller that sees that the BNXT_FLTR_INSERTED flag is set can delete
the filter structure and clear the flag under spinlock.

Reviewed-by: Vasundhara Volam <vasundhara-v.volam@broadcom.com>
Reviewed-by: Andy Gospodarek <andrew.gospodarek@broadcom.com>
Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/bnxt/bnxt.c

@@ -5343,6 +5343,10 @@ void bnxt_del_l2_filter(struct bnxt *bp, struct bnxt_l2_filter *fltr)
 	if (!atomic_dec_and_test(&fltr->refcnt))
 		return;
 	spin_lock_bh(&bp->ntp_fltr_lock);
+	if (!test_and_clear_bit(BNXT_FLTR_INSERTED, &fltr->base.state)) {
+		spin_unlock_bh(&bp->ntp_fltr_lock);
+		return;
+	}
 	hlist_del_rcu(&fltr->base.hash);
 	if (fltr->base.flags) {
 		clear_bit(fltr->base.sw_id, bp->ntp_fltr_bmap);
@@ -5489,6 +5493,7 @@ static int bnxt_init_l2_filter(struct bnxt *bp, struct bnxt_l2_filter *fltr,
 	}
 	head = &bp->l2_fltr_hash_tbl[idx];
 	hlist_add_head_rcu(&fltr->base.hash, head);
+	set_bit(BNXT_FLTR_INSERTED, &fltr->base.state);
 	atomic_set(&fltr->refcnt, 1);
 	return 0;
 }
@@ -14000,6 +14005,7 @@ static int bnxt_rx_flow_steer(struct net_device *dev, const struct sk_buff *skb,
 	new_fltr->base.type = BNXT_FLTR_TYPE_NTUPLE;
 	new_fltr->base.flags = BNXT_ACT_RING_DST;
 	hlist_add_head_rcu(&new_fltr->base.hash, head);
+	set_bit(BNXT_FLTR_INSERTED, &new_fltr->base.state);
 	bp->ntp_fltr_count++;
 	spin_unlock_bh(&bp->ntp_fltr_lock);
 
@@ -14046,6 +14052,10 @@ static void bnxt_cfg_ntp_filters(struct bnxt *bp)
 
 			if (del) {
 				spin_lock_bh(&bp->ntp_fltr_lock);
+				if (!test_and_clear_bit(BNXT_FLTR_INSERTED, &fltr->base.state)) {
+					spin_unlock_bh(&bp->ntp_fltr_lock);
+					continue;
+				}
 				hlist_del_rcu(&fltr->base.hash);
 				bp->ntp_fltr_count--;
 				spin_unlock_bh(&bp->ntp_fltr_lock);

drivers/net/ethernet/broadcom/bnxt/bnxt.h

@@ -1348,7 +1348,7 @@ struct bnxt_filter_base {
 	u16			vf_idx;
 	unsigned long		state;
 #define BNXT_FLTR_VALID		0
-#define BNXT_FLTR_UPDATE	1
+#define BNXT_FLTR_INSERTED	1
 
 	struct rcu_head         rcu;
 };