Subject: Re: [PATCH net-next 4/8] net: bonding: constify and use dev_addr_set()

From: Jay Vosburgh <[email-masked]>
Date: Fri, 22 Oct 2021 11:39:06 -0700

Jakub Kicinski <[email-masked]> wrote:

>Commit 406f42fa0d3c ("net-next: When a bond have a massive amount
>of VLANs...") introduced a rbtree for faster Ethernet address look
>up. To maintain netdev->dev_addr in this tree we need to make all
>the writes to it got through appropriate helpers.

	Should the above be "go through"?

	-J

>Make sure local references to netdev->dev_addr are constant.
>
>Signed-off-by: Jakub Kicinski <[email-masked]>
>---
>CC: [email-masked]
>CC: [email-masked]
>CC: [email-masked]
>---
> drivers/net/bonding/bond_alb.c  | 28 +++++++++++++---------------
> drivers/net/bonding/bond_main.c |  2 +-
> 2 files changed, 14 insertions(+), 16 deletions(-)
>
>diff --git a/drivers/net/bonding/bond_alb.c b/drivers/net/bonding/bond_alb.c
>index 7d3752cbf761..2ec8e015c7b3 100644
>--- a/drivers/net/bonding/bond_alb.c
>+++ b/drivers/net/bonding/bond_alb.c
>@@ -50,7 +50,7 @@ struct arp_pkt {
> #pragma pack()
> 
> /* Forward declaration */
>-static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[],
>+static void alb_send_learning_packets(struct slave *slave, const u8 mac_addr[],
> 				      bool strict_match);
> static void rlb_purge_src_ip(struct bonding *bond, struct arp_pkt *arp);
> static void rlb_src_unlink(struct bonding *bond, u32 index);
>@@ -353,7 +353,8 @@ static struct slave *rlb_next_rx_slave(struct bonding *bond)
>  *
>  * Caller must hold RTNL
>  */
>-static void rlb_teach_disabled_mac_on_primary(struct bonding *bond, u8 addr[])
>+static void rlb_teach_disabled_mac_on_primary(struct bonding *bond,
>+					      const u8 addr[])
> {
> 	struct slave *curr_active = rtnl_dereference(bond->curr_active_slave);
> 
>@@ -904,7 +905,7 @@ static void rlb_clear_vlan(struct bonding *bond, unsigned short vlan_id)
> 
> /*********************** tlb/rlb shared functions *********************/
> 
>-static void alb_send_lp_vid(struct slave *slave, u8 mac_addr[],
>+static void alb_send_lp_vid(struct slave *slave, const u8 mac_addr[],
> 			    __be16 vlan_proto, u16 vid)
> {
> 	struct learning_pkt pkt;
>@@ -940,7 +941,7 @@ static void alb_send_lp_vid(struct slave *slave, u8 mac_addr[],
> struct alb_walk_data {
> 	struct bonding *bond;
> 	struct slave *slave;
>-	u8 *mac_addr;
>+	const u8 *mac_addr;
> 	bool strict_match;
> };
> 
>@@ -949,9 +950,9 @@ static int alb_upper_dev_walk(struct net_device *upper,
> {
> 	struct alb_walk_data *data = (struct alb_walk_data *)priv->data;
> 	bool strict_match = data->strict_match;
>+	const u8 *mac_addr = data->mac_addr;
> 	struct bonding *bond = data->bond;
> 	struct slave *slave = data->slave;
>-	u8 *mac_addr = data->mac_addr;
> 	struct bond_vlan_tag *tags;
> 
> 	if (is_vlan_dev(upper) &&
>@@ -982,7 +983,7 @@ static int alb_upper_dev_walk(struct net_device *upper,
> 	return 0;
> }
> 
>-static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[],
>+static void alb_send_learning_packets(struct slave *slave, const u8 mac_addr[],
> 				      bool strict_match)
> {
> 	struct bonding *bond = bond_get_bond_by_slave(slave);
>@@ -1006,14 +1007,14 @@ static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[],
> 	rcu_read_unlock();
> }
> 
>-static int alb_set_slave_mac_addr(struct slave *slave, u8 addr[],
>+static int alb_set_slave_mac_addr(struct slave *slave, const u8 addr[],
> 				  unsigned int len)
> {
> 	struct net_device *dev = slave->dev;
> 	struct sockaddr_storage ss;
> 
> 	if (BOND_MODE(slave->bond) == BOND_MODE_TLB) {
>-		memcpy(dev->dev_addr, addr, len);
>+		__dev_addr_set(dev, addr, len);
> 		return 0;
> 	}
> 
>@@ -1242,8 +1243,7 @@ static int alb_set_mac_address(struct bonding *bond, void *addr)
> 		res = dev_set_mac_address(slave->dev, addr, NULL);
> 
> 		/* restore net_device's hw address */
>-		bond_hw_addr_copy(slave->dev->dev_addr, tmp_addr,
>-				  slave->dev->addr_len);
>+		dev_addr_set(slave->dev, tmp_addr);
> 
> 		if (res)
> 			goto unwind;
>@@ -1263,8 +1263,7 @@ static int alb_set_mac_address(struct bonding *bond, void *addr)
> 				  rollback_slave->dev->addr_len);
> 		dev_set_mac_address(rollback_slave->dev,
> 				    (struct sockaddr *)&ss, NULL);
>-		bond_hw_addr_copy(rollback_slave->dev->dev_addr, tmp_addr,
>-				  rollback_slave->dev->addr_len);
>+		dev_addr_set(rollback_slave->dev, tmp_addr);
> 	}
> 
> 	return res;
>@@ -1727,8 +1726,7 @@ void bond_alb_handle_active_change(struct bonding *bond, struct slave *new_slave
> 		dev_set_mac_address(new_slave->dev, (struct sockaddr *)&ss,
> 				    NULL);
> 
>-		bond_hw_addr_copy(new_slave->dev->dev_addr, tmp_addr,
>-				  new_slave->dev->addr_len);
>+		dev_addr_set(new_slave->dev, tmp_addr);
> 	}
> 
> 	/* curr_active_slave must be set before calling alb_swap_mac_addr */
>@@ -1761,7 +1759,7 @@ int bond_alb_set_mac_address(struct net_device *bond_dev, void *addr)
> 	if (res)
> 		return res;
> 
>-	bond_hw_addr_copy(bond_dev->dev_addr, ss->__data, bond_dev->addr_len);
>+	dev_addr_set(bond_dev, ss->__data);
> 
> 	/* If there is no curr_active_slave there is nothing else to do.
> 	 * Otherwise we'll need to pass the new address to it and handle
>diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
>index 0c52612cb8e9..ff8da720a33a 100644
>--- a/drivers/net/bonding/bond_main.c
>+++ b/drivers/net/bonding/bond_main.c
>@@ -923,7 +923,7 @@ static int bond_set_dev_addr(struct net_device *bond_dev,
> 	if (err)
> 		return err;
> 
>-	memcpy(bond_dev->dev_addr, slave_dev->dev_addr, slave_dev->addr_len);
>+	__dev_addr_set(bond_dev, slave_dev->dev_addr, slave_dev->addr_len);
> 	bond_dev->addr_assign_type = NET_ADDR_STOLEN;
> 	call_netdevice_notifiers(NETDEV_CHANGEADDR, bond_dev);
> 	return 0;
>-- 
>2.31.1
>

---
	-Jay Vosburgh, [email-masked]