Merge branch 'gve-xdp-fixes'

Joshua Washington says:

====================
gve: various XDP fixes

This patch series contains the following XDP fixes:
 - clean up XDP tx queue when stopping rings
 - use RCU synchronization to guard existence of XDP queues
 - perform XSK TX as part of RX NAPI to fix busy polling
 - fix XDP allocation issues when non-XDP configurations occur
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 60 insertions, 29 deletions

diff --git a/drivers/net/ethernet/google/gve/gve.h b/drivers/net/ethernet/google/gve/gve.h
index dd92949bb214..8167cc5fb0df 100644
--- a/drivers/net/ethernet/google/gve/gve.h
+++ b/drivers/net/ethernet/google/gve/gve.h
@@ -1140,6 +1140,7 @@ int gve_xdp_xmit_one(struct gve_priv *priv, struct gve_tx_ring *tx,
 void gve_xdp_tx_flush(struct gve_priv *priv, u32 xdp_qid);
 bool gve_tx_poll(struct gve_notify_block *block, int budget);
 bool gve_xdp_poll(struct gve_notify_block *block, int budget);
+int gve_xsk_tx_poll(struct gve_notify_block *block, int budget);
 int gve_tx_alloc_rings_gqi(struct gve_priv *priv,
 			   struct gve_tx_alloc_rings_cfg *cfg);
 void gve_tx_free_rings_gqi(struct gve_priv *priv,
diff --git a/drivers/net/ethernet/google/gve/gve_main.c b/drivers/net/ethernet/google/gve/gve_main.c
index e171ca248f9a..09fb7f16f73e 100644
--- a/drivers/net/ethernet/google/gve/gve_main.c
+++ b/drivers/net/ethernet/google/gve/gve_main.c
@@ -333,6 +333,14 @@ int gve_napi_poll(struct napi_struct *napi, int budget)
 
 	if (block->rx) {
 		work_done = gve_rx_poll(block, budget);
+
+		/* Poll XSK TX as part of RX NAPI. Setup re-poll based on max of
+		 * TX and RX work done.
+		 */
+		if (priv->xdp_prog)
+			work_done = max_t(int, work_done,
+					  gve_xsk_tx_poll(block, budget));
+
 		reschedule |= work_done == budget;
 	}
 
@@ -922,11 +930,13 @@ static void gve_init_sync_stats(struct gve_priv *priv)
 static void gve_tx_get_curr_alloc_cfg(struct gve_priv *priv,
 				      struct gve_tx_alloc_rings_cfg *cfg)
 {
+	int num_xdp_queues = priv->xdp_prog ? priv->rx_cfg.num_queues : 0;
+
 	cfg->qcfg = &priv->tx_cfg;
 	cfg->raw_addressing = !gve_is_qpl(priv);
 	cfg->ring_size = priv->tx_desc_cnt;
 	cfg->start_idx = 0;
-	cfg->num_rings = gve_num_tx_queues(priv);
+	cfg->num_rings = priv->tx_cfg.num_queues + num_xdp_queues;
 	cfg->tx = priv->tx;
 }
 
@@ -1623,8 +1633,8 @@ static int gve_xsk_pool_enable(struct net_device *dev,
 	if (err)
 		return err;
 
-	/* If XDP prog is not installed, return */
-	if (!priv->xdp_prog)
+	/* If XDP prog is not installed or interface is down, return. */
+	if (!priv->xdp_prog || !netif_running(dev))
 		return 0;
 
 	rx = &priv->rx[qid];
@@ -1669,21 +1679,16 @@ static int gve_xsk_pool_disable(struct net_device *dev,
 	if (qid >= priv->rx_cfg.num_queues)
 		return -EINVAL;
 
-	/* If XDP prog is not installed, unmap DMA and return */
-	if (!priv->xdp_prog)
-		goto done;
-
-	tx_qid = gve_xdp_tx_queue_id(priv, qid);
-	if (!netif_running(dev)) {
-		priv->rx[qid].xsk_pool = NULL;
-		xdp_rxq_info_unreg(&priv->rx[qid].xsk_rxq);
-		priv->tx[tx_qid].xsk_pool = NULL;
+	/* If XDP prog is not installed or interface is down, unmap DMA and
+	 * return.
+	 */
+	if (!priv->xdp_prog || !netif_running(dev))
 		goto done;
-	}
 
 	napi_rx = &priv->ntfy_blocks[priv->rx[qid].ntfy_id].napi;
 	napi_disable(napi_rx); /* make sure current rx poll is done */
 
+	tx_qid = gve_xdp_tx_queue_id(priv, qid);
 	napi_tx = &priv->ntfy_blocks[priv->tx[tx_qid].ntfy_id].napi;
 	napi_disable(napi_tx); /* make sure current tx poll is done */
 
@@ -1711,6 +1716,9 @@ static int gve_xsk_wakeup(struct net_device *dev, u32 queue_id, u32 flags)
 	struct gve_priv *priv = netdev_priv(dev);
 	int tx_queue_id = gve_xdp_tx_queue_id(priv, queue_id);
 
+	if (!gve_get_napi_enabled(priv))
+		return -ENETDOWN;
+
 	if (queue_id >= priv->rx_cfg.num_queues || !priv->xdp_prog)
 		return -EINVAL;
 
@@ -1837,6 +1845,7 @@ int gve_adjust_queues(struct gve_priv *priv,
 {
 	struct gve_tx_alloc_rings_cfg tx_alloc_cfg = {0};
 	struct gve_rx_alloc_rings_cfg rx_alloc_cfg = {0};
+	int num_xdp_queues;
 	int err;
 
 	gve_get_curr_alloc_cfgs(priv, &tx_alloc_cfg, &rx_alloc_cfg);
@@ -1847,6 +1856,10 @@ int gve_adjust_queues(struct gve_priv *priv,
 	rx_alloc_cfg.qcfg = &new_rx_config;
 	tx_alloc_cfg.num_rings = new_tx_config.num_queues;
 
+	/* Add dedicated XDP TX queues if enabled. */
+	num_xdp_queues = priv->xdp_prog ? new_rx_config.num_queues : 0;
+	tx_alloc_cfg.num_rings += num_xdp_queues;
+
 	if (netif_running(priv->dev)) {
 		err = gve_adjust_config(priv, &tx_alloc_cfg, &rx_alloc_cfg);
 		return err;
@@ -1899,6 +1912,9 @@ static void gve_turndown(struct gve_priv *priv)
 
 	gve_clear_napi_enabled(priv);
 	gve_clear_report_stats(priv);
+
+	/* Make sure that all traffic is finished processing. */
+	synchronize_net();
 }
 
 static void gve_turnup(struct gve_priv *priv)
diff --git a/drivers/net/ethernet/google/gve/gve_tx.c b/drivers/net/ethernet/google/gve/gve_tx.c
index e7fb7d6d283d..4350ebd9c2bd 100644
--- a/drivers/net/ethernet/google/gve/gve_tx.c
+++ b/drivers/net/ethernet/google/gve/gve_tx.c
@@ -206,7 +206,10 @@ void gve_tx_stop_ring_gqi(struct gve_priv *priv, int idx)
 		return;
 
 	gve_remove_napi(priv, ntfy_idx);
-	gve_clean_tx_done(priv, tx, priv->tx_desc_cnt, false);
+	if (tx->q_num < priv->tx_cfg.num_queues)
+		gve_clean_tx_done(priv, tx, priv->tx_desc_cnt, false);
+	else
+		gve_clean_xdp_done(priv, tx, priv->tx_desc_cnt);
 	netdev_tx_reset_queue(tx->netdev_txq);
 	gve_tx_remove_from_block(priv, idx);
 }
@@ -834,9 +837,12 @@ int gve_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **frames,
 	struct gve_tx_ring *tx;
 	int i, err = 0, qid;
 
-	if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK))
+	if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK) || !priv->xdp_prog)
 		return -EINVAL;
 
+	if (!gve_get_napi_enabled(priv))
+		return -ENETDOWN;
+
 	qid = gve_xdp_tx_queue_id(priv,
 				  smp_processor_id() % priv->num_xdp_queues);
 
@@ -975,33 +981,41 @@ out:
 	return sent;
 }
 
+int gve_xsk_tx_poll(struct gve_notify_block *rx_block, int budget)
+{
+	struct gve_rx_ring *rx = rx_block->rx;
+	struct gve_priv *priv = rx->gve;
+	struct gve_tx_ring *tx;
+	int sent = 0;
+
+	tx = &priv->tx[gve_xdp_tx_queue_id(priv, rx->q_num)];
+	if (tx->xsk_pool) {
+		sent = gve_xsk_tx(priv, tx, budget);
+
+		u64_stats_update_begin(&tx->statss);
+		tx->xdp_xsk_sent += sent;
+		u64_stats_update_end(&tx->statss);
+		if (xsk_uses_need_wakeup(tx->xsk_pool))
+			xsk_set_tx_need_wakeup(tx->xsk_pool);
+	}
+
+	return sent;
+}
+
 bool gve_xdp_poll(struct gve_notify_block *block, int budget)
 {
 	struct gve_priv *priv = block->priv;
 	struct gve_tx_ring *tx = block->tx;
 	u32 nic_done;
-	bool repoll;
 	u32 to_do;
 
 	/* Find out how much work there is to be done */
 	nic_done = gve_tx_load_event_counter(priv, tx);
 	to_do = min_t(u32, (nic_done - tx->done), budget);
 	gve_clean_xdp_done(priv, tx, to_do);
-	repoll = nic_done != tx->done;
-
-	if (tx->xsk_pool) {
-		int sent = gve_xsk_tx(priv, tx, budget);
-
-		u64_stats_update_begin(&tx->statss);
-		tx->xdp_xsk_sent += sent;
-		u64_stats_update_end(&tx->statss);
-		repoll |= (sent == budget);
-		if (xsk_uses_need_wakeup(tx->xsk_pool))
-			xsk_set_tx_need_wakeup(tx->xsk_pool);
-	}
 
 	/* If we still have work we want to repoll */
-	return repoll;
+	return nic_done != tx->done;
 }
 
 bool gve_tx_poll(struct gve_notify_block *block, int budget)