Merge branch 'dpaa2-switch-various-improvements'

Ioana Ciornei says:

====================
dpaa2-switch: various improvements

This patch set is a comprised of improvements and fixes for
long-standing bugs which were only caught by sashiko while reviewing the
LAG support patches for the dpaa2-switch:
https://lore.kernel.org/all/20260512131554.952971-1-ioana.ciornei@nxp.com/

In order to not just add to the already big set, I am submitting these
before any v3 of the LAG support patches.

The individual patches tackle FDB and VLAN management in the
dpaa2-switch driver as well as removal of some duplicated code. The
error path of the dpaa2_switch_rx() is also improved.
====================

Link: https://patch.msgid.link/20260528173452.1953102-1-ioana.ciornei@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 104 insertions, 75 deletions

diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.c b/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.c
index 52c1cb9cb7e0..a0bf5b50aae5 100644
--- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.c
+++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.c
@@ -54,27 +54,44 @@ dpaa2_switch_filter_block_get_unused(struct ethsw_core *ethsw)
 static u16 dpaa2_switch_port_set_fdb(struct ethsw_port_priv *port_priv,
 				     struct net_device *bridge_dev)
 {
+	struct ethsw_core *ethsw = port_priv->ethsw_data;
 	struct ethsw_port_priv *other_port_priv = NULL;
 	struct dpaa2_switch_fdb *fdb;
 	struct net_device *other_dev;
+	bool last_fdb_user = true;
 	struct list_head *iter;
+	int i;
 
 	/* If we leave a bridge (bridge_dev is NULL), find an unused
 	 * FDB and use that.
 	 */
 	if (!bridge_dev) {
-		fdb = dpaa2_switch_fdb_get_unused(port_priv->ethsw_data);
-
-		/* If there is no unused FDB, we must be the last port that
-		 * leaves the last bridge, all the others are standalone. We
-		 * can just keep the FDB that we already have.
-		 */
+		/* First verify if this is the last port to leave this bridge */
+		for (i = 0; i < ethsw->sw_attr.num_ifs; i++) {
+			if (!ethsw->ports[i] || ethsw->ports[i] == port_priv)
+				continue;
+			if (ethsw->ports[i]->fdb == port_priv->fdb) {
+				last_fdb_user = false;
+				break;
+			}
+		}
 
-		if (!fdb) {
+		/* If this is the last user of the FDB, just keep using it. */
+		if (last_fdb_user) {
 			port_priv->fdb->bridge_dev = NULL;
 			return 0;
 		}
 
+		/* Since we are not the last port which leaves a bridge,
+		 * acquire a new FDB and use it. The number of FDBs is sized to
+		 * accommodate all switch ports as standalone, each with its
+		 * private FDB, which means that dpaa2_switch_fdb_get_unused()
+		 * must succeed here. WARN if not.
+		 */
+		fdb = dpaa2_switch_fdb_get_unused(port_priv->ethsw_data);
+		if (WARN_ON(!fdb))
+			return 0;
+
 		port_priv->fdb = fdb;
 		port_priv->fdb->in_use = true;
 		port_priv->fdb->bridge_dev = NULL;
@@ -281,49 +298,68 @@ set_tci_error:
 }
 
 static int dpaa2_switch_port_add_vlan(struct ethsw_port_priv *port_priv,
-				      u16 vid, u16 flags)
+				      u16 vid, u16 flags, bool changed)
 {
 	struct ethsw_core *ethsw = port_priv->ethsw_data;
 	struct net_device *netdev = port_priv->netdev;
 	struct dpsw_vlan_if_cfg vcfg = {0};
 	int err;
 
-	if (port_priv->vlans[vid]) {
-		netdev_err(netdev, "VLAN %d already configured\n", vid);
-		return -EEXIST;
+	if (!port_priv->vlans[vid]) {
+		/* If hit, this VLAN rule will lead the packet into the FDB
+		 * table specified in the vlan configuration below
+		 */
+		vcfg.num_ifs = 1;
+		vcfg.if_id[0] = port_priv->idx;
+		vcfg.fdb_id = dpaa2_switch_port_get_fdb_id(port_priv);
+		vcfg.options |= DPSW_VLAN_ADD_IF_OPT_FDB_ID;
+		err = dpsw_vlan_add_if(ethsw->mc_io, 0, ethsw->dpsw_handle,
+				       vid, &vcfg);
+		if (err) {
+			netdev_err(netdev, "dpsw_vlan_add_if err %d\n", err);
+			return err;
+		}
+
+		port_priv->vlans[vid] = ETHSW_VLAN_MEMBER;
 	}
 
-	/* If hit, this VLAN rule will lead the packet into the FDB table
-	 * specified in the vlan configuration below
-	 */
+	memset(&vcfg, 0, sizeof(vcfg));
 	vcfg.num_ifs = 1;
 	vcfg.if_id[0] = port_priv->idx;
-	vcfg.fdb_id = dpaa2_switch_port_get_fdb_id(port_priv);
-	vcfg.options |= DPSW_VLAN_ADD_IF_OPT_FDB_ID;
-	err = dpsw_vlan_add_if(ethsw->mc_io, 0, ethsw->dpsw_handle, vid, &vcfg);
-	if (err) {
-		netdev_err(netdev, "dpsw_vlan_add_if err %d\n", err);
-		return err;
-	}
-
-	port_priv->vlans[vid] = ETHSW_VLAN_MEMBER;
 
 	if (flags & BRIDGE_VLAN_INFO_UNTAGGED) {
-		err = dpsw_vlan_add_if_untagged(ethsw->mc_io, 0,
-						ethsw->dpsw_handle,
-						vid, &vcfg);
+		if (!(port_priv->vlans[vid] & ETHSW_VLAN_UNTAGGED)) {
+			err = dpsw_vlan_add_if_untagged(ethsw->mc_io, 0,
+							ethsw->dpsw_handle,
+							vid, &vcfg);
+			if (err) {
+				netdev_err(netdev,
+					   "dpsw_vlan_add_if_untagged err %d\n",
+					   err);
+				return err;
+			}
+			port_priv->vlans[vid] |= ETHSW_VLAN_UNTAGGED;
+		}
+	} else if (changed && (port_priv->vlans[vid] & ETHSW_VLAN_UNTAGGED)) {
+		err = dpsw_vlan_remove_if_untagged(ethsw->mc_io, 0,
+						   ethsw->dpsw_handle,
+						   vid, &vcfg);
 		if (err) {
 			netdev_err(netdev,
-				   "dpsw_vlan_add_if_untagged err %d\n", err);
-			return err;
+				   "dpsw_vlan_remove_if_untagged err %d\n",
+				   err);
 		}
-		port_priv->vlans[vid] |= ETHSW_VLAN_UNTAGGED;
+		port_priv->vlans[vid] &= ~ETHSW_VLAN_UNTAGGED;
 	}
 
 	if (flags & BRIDGE_VLAN_INFO_PVID) {
 		err = dpaa2_switch_port_set_pvid(port_priv, vid);
 		if (err)
 			return err;
+	} else if (changed && port_priv->vlans[vid] & ETHSW_VLAN_PVID) {
+		err = dpaa2_switch_port_set_pvid(port_priv, 4095);
+		if (err)
+			return err;
 	}
 
 	return 0;
@@ -953,6 +989,7 @@ static int dpaa2_switch_port_vlan_add(struct net_device *netdev, __be16 proto,
 		.obj.orig_dev = netdev,
 		/* This API only allows programming tagged, non-PVID VIDs */
 		.flags = 0,
+		.changed = false,
 	};
 
 	return dpaa2_switch_port_vlans_add(netdev, &vlan);
@@ -1786,35 +1823,19 @@ int dpaa2_switch_port_vlans_add(struct net_device *netdev,
 	struct dpsw_attr *attr = &ethsw->sw_attr;
 	int err = 0;
 
-	/* Make sure that the VLAN is not already configured
-	 * on the switch port
-	 */
-	if (port_priv->vlans[vlan->vid] & ETHSW_VLAN_MEMBER) {
-		netdev_err(netdev, "VLAN %d already configured\n", vlan->vid);
-		return -EEXIST;
-	}
-
-	/* Check if there is space for a new VLAN */
-	err = dpsw_get_attributes(ethsw->mc_io, 0, ethsw->dpsw_handle,
-				  &ethsw->sw_attr);
-	if (err) {
-		netdev_err(netdev, "dpsw_get_attributes err %d\n", err);
-		return err;
-	}
-	if (attr->max_vlans - attr->num_vlans < 1)
-		return -ENOSPC;
-
-	/* Check if there is space for a new VLAN */
-	err = dpsw_get_attributes(ethsw->mc_io, 0, ethsw->dpsw_handle,
-				  &ethsw->sw_attr);
-	if (err) {
-		netdev_err(netdev, "dpsw_get_attributes err %d\n", err);
-		return err;
-	}
-	if (attr->max_vlans - attr->num_vlans < 1)
-		return -ENOSPC;
-
 	if (!port_priv->ethsw_data->vlans[vlan->vid]) {
+		/* Only check for space in case this is a new VLAN from the
+		 * DPSW perspective
+		 */
+		err = dpsw_get_attributes(ethsw->mc_io, 0, ethsw->dpsw_handle,
+					  &ethsw->sw_attr);
+		if (err) {
+			netdev_err(netdev, "dpsw_get_attributes err %d\n", err);
+			return err;
+		}
+		if (attr->max_vlans - attr->num_vlans < 1)
+			return -ENOSPC;
+
 		/* this is a new VLAN */
 		err = dpaa2_switch_add_vlan(port_priv, vlan->vid);
 		if (err)
@@ -1823,7 +1844,8 @@ int dpaa2_switch_port_vlans_add(struct net_device *netdev,
 		port_priv->ethsw_data->vlans[vlan->vid] |= ETHSW_VLAN_GLOBAL;
 	}
 
-	return dpaa2_switch_port_add_vlan(port_priv, vlan->vid, vlan->flags);
+	return dpaa2_switch_port_add_vlan(port_priv, vlan->vid, vlan->flags,
+					  vlan->changed);
 }
 
 static int dpaa2_switch_port_lookup_address(struct net_device *netdev, int is_uc,
@@ -2139,7 +2161,8 @@ static int dpaa2_switch_port_bridge_leave(struct net_device *netdev)
 	 * the dpaa2 switch interfaces are not capable to be VLAN unaware
 	 */
 	return dpaa2_switch_port_add_vlan(port_priv, DEFAULT_VLAN_ID,
-					  BRIDGE_VLAN_INFO_UNTAGGED | BRIDGE_VLAN_INFO_PVID);
+					  BRIDGE_VLAN_INFO_UNTAGGED | BRIDGE_VLAN_INFO_PVID,
+					  false);
 }
 
 static int dpaa2_switch_prevent_bridging_with_8021q_upper(struct net_device *netdev)
@@ -2412,18 +2435,13 @@ static int dpaa2_switch_port_blocking_event(struct notifier_block *nb,
 
 /* Build a linear skb based on a single-buffer frame descriptor */
 static struct sk_buff *dpaa2_switch_build_linear_skb(struct ethsw_core *ethsw,
-						     const struct dpaa2_fd *fd)
+						     const struct dpaa2_fd *fd,
+						     void *fd_vaddr)
 {
 	u16 fd_offset = dpaa2_fd_get_offset(fd);
-	dma_addr_t addr = dpaa2_fd_get_addr(fd);
 	u32 fd_length = dpaa2_fd_get_len(fd);
 	struct device *dev = ethsw->dev;
 	struct sk_buff *skb = NULL;
-	void *fd_vaddr;
-
-	fd_vaddr = dpaa2_iova_to_virt(ethsw->iommu_domain, addr);
-	dma_unmap_page(dev, addr, DPAA2_SWITCH_RX_BUF_SIZE,
-		       DMA_FROM_DEVICE);
 
 	skb = build_skb(fd_vaddr, DPAA2_SWITCH_RX_BUF_SIZE +
 			SKB_DATA_ALIGN(sizeof(struct skb_shared_info)));
@@ -2449,6 +2467,7 @@ static void dpaa2_switch_tx_conf(struct dpaa2_switch_fq *fq,
 static void dpaa2_switch_rx(struct dpaa2_switch_fq *fq,
 			    const struct dpaa2_fd *fd)
 {
+	dma_addr_t addr = dpaa2_fd_get_addr(fd);
 	struct ethsw_core *ethsw = fq->ethsw;
 	struct ethsw_port_priv *port_priv;
 	struct net_device *netdev;
@@ -2456,10 +2475,14 @@ static void dpaa2_switch_rx(struct dpaa2_switch_fq *fq,
 	struct sk_buff *skb;
 	u16 vlan_tci, vid;
 	int if_id, err;
+	void *vaddr;
+
+	vaddr = dpaa2_iova_to_virt(ethsw->iommu_domain, addr);
+	dma_unmap_page(ethsw->dev, addr, DPAA2_SWITCH_RX_BUF_SIZE,
+		       DMA_FROM_DEVICE);
 
 	/* get switch ingress interface ID */
 	if_id = upper_32_bits(dpaa2_fd_get_flc(fd)) & 0x0000FFFF;
-
 	if (if_id >= ethsw->sw_attr.num_ifs) {
 		dev_err(ethsw->dev, "Frame received from unknown interface!\n");
 		goto err_free_fd;
@@ -2475,7 +2498,7 @@ static void dpaa2_switch_rx(struct dpaa2_switch_fq *fq,
 		}
 	}
 
-	skb = dpaa2_switch_build_linear_skb(ethsw, fd);
+	skb = dpaa2_switch_build_linear_skb(ethsw, fd, vaddr);
 	if (unlikely(!skb))
 		goto err_free_fd;
 
@@ -2493,7 +2516,8 @@ static void dpaa2_switch_rx(struct dpaa2_switch_fq *fq,
 		err = __skb_vlan_pop(skb, &vlan_tci);
 		if (err) {
 			dev_info(ethsw->dev, "__skb_vlan_pop() returned %d", err);
-			goto err_free_fd;
+			kfree_skb(skb);
+			return;
 		}
 	}
 
@@ -2508,7 +2532,7 @@ static void dpaa2_switch_rx(struct dpaa2_switch_fq *fq,
 	return;
 
 err_free_fd:
-	dpaa2_switch_free_fd(ethsw, fd);
+	free_pages((unsigned long)vaddr, 0);
 }
 
 static void dpaa2_switch_detect_features(struct ethsw_core *ethsw)
@@ -3280,7 +3304,6 @@ static void dpaa2_switch_teardown(struct fsl_mc_device *sw_dev)
 
 static void dpaa2_switch_remove(struct fsl_mc_device *sw_dev)
 {
-	struct ethsw_port_priv *port_priv;
 	struct ethsw_core *ethsw;
 	struct device *dev;
 	int i;
@@ -3292,11 +3315,17 @@ static void dpaa2_switch_remove(struct fsl_mc_device *sw_dev)
 
 	dpsw_disable(ethsw->mc_io, 0, ethsw->dpsw_handle);
 
-	for (i = 0; i < ethsw->sw_attr.num_ifs; i++) {
-		port_priv = ethsw->ports[i];
-		unregister_netdev(port_priv->netdev);
+	/* Unregister all the netdevs so that they are brought down and the
+	 * shared NAPI instances gets disabled.
+	 */
+	for (i = 0; i < ethsw->sw_attr.num_ifs; i++)
+		unregister_netdev(ethsw->ports[i]->netdev);
+
+	for (i = 0; i < DPAA2_SWITCH_RX_NUM_FQS; i++)
+		netif_napi_del(&ethsw->fq[i].napi);
+
+	for (i = 0; i < ethsw->sw_attr.num_ifs; i++)
 		dpaa2_switch_remove_port(ethsw, i);
-	}
 
 	kfree(ethsw->fdbs);
 	kfree(ethsw->filter_blocks);