From: Maor Gottlieb <maorg@mellanox.com>
Date: Thu, 30 Apr 2020 22:21:38 +0300
Subject: bonding: Add array of all slaves
Patch-mainline: v5.8-rc1
Git-commit: 6b447e76ed44cc354cd0a346b86efe393e603e0d
References: bsc#1176447

Keep all slaves in array so it could be used to get the xmit slave
assume all the slaves are active.
The logic to add slave to the array is like the usable slaves, except
that we also add slaves that currently can't transmit - not up or active.

Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Jay Vosburgh <jay.vosburgh@canonical.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/bonding/bond_main.c |   78 ++++++++++++++++++++++++++++++----------
 include/net/bonding.h           |    3 +
 2 files changed, 61 insertions(+), 20 deletions(-)

--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -4117,6 +4117,38 @@ static void bond_skip_slave(struct bond_
 	}
 }
 
+static void bond_set_slave_arr(struct bonding *bond,
+			       struct bond_up_slave *usable_slaves,
+			       struct bond_up_slave *all_slaves)
+{
+	struct bond_up_slave *usable, *all;
+
+	usable = rtnl_dereference(bond->usable_slaves);
+	rcu_assign_pointer(bond->usable_slaves, usable_slaves);
+	kfree_rcu(usable, rcu);
+
+	all = rtnl_dereference(bond->all_slaves);
+	rcu_assign_pointer(bond->all_slaves, all_slaves);
+	kfree_rcu(all, rcu);
+}
+
+static void bond_reset_slave_arr(struct bonding *bond)
+{
+	struct bond_up_slave *usable, *all;
+
+	usable = rtnl_dereference(bond->usable_slaves);
+	if (usable) {
+		RCU_INIT_POINTER(bond->usable_slaves, NULL);
+		kfree_rcu(usable, rcu);
+	}
+
+	all = rtnl_dereference(bond->all_slaves);
+	if (all) {
+		RCU_INIT_POINTER(bond->all_slaves, NULL);
+		kfree_rcu(all, rcu);
+	}
+}
+
 /* Build the usable slaves array in control path for modes that use xmit-hash
  * to determine the slave interface -
  * (a) BOND_MODE_8023AD
@@ -4127,7 +4159,7 @@ static void bond_skip_slave(struct bond_
  */
 int bond_update_slave_arr(struct bonding *bond, struct slave *skipslave)
 {
-	struct bond_up_slave *usable_slaves, *old_usable_slaves;
+	struct bond_up_slave *usable_slaves = NULL, *all_slaves = NULL;
 	struct slave *slave;
 	struct list_head *iter;
 	int agg_id = 0;
@@ -4139,7 +4171,9 @@ int bond_update_slave_arr(struct bonding
 
 	usable_slaves = kzalloc(struct_size(usable_slaves, arr,
 					    bond->slave_cnt), GFP_KERNEL);
-	if (!usable_slaves) {
+	all_slaves = kzalloc(struct_size(all_slaves, arr,
+					 bond->slave_cnt), GFP_KERNEL);
+	if (!usable_slaves || !all_slaves) {
 		ret = -ENOMEM;
 		goto out;
 	}
@@ -4148,20 +4182,19 @@ int bond_update_slave_arr(struct bonding
 
 		if (bond_3ad_get_active_agg_info(bond, &ad_info)) {
 			pr_debug("bond_3ad_get_active_agg_info failed\n");
-			kfree_rcu(usable_slaves, rcu);
 			/* No active aggragator means it's not safe to use
 			 * the previous array.
 			 */
-			old_usable_slaves = rtnl_dereference(bond->usable_slaves);
-			if (old_usable_slaves) {
-				RCU_INIT_POINTER(bond->usable_slaves, NULL);
-				kfree_rcu(old_usable_slaves, rcu);
-			}
+			bond_reset_slave_arr(bond);
 			goto out;
 		}
 		agg_id = ad_info.aggregator_id;
 	}
 	bond_for_each_slave(bond, slave, iter) {
+		if (skipslave == slave)
+			continue;
+
+		all_slaves->arr[all_slaves->count++] = slave;
 		if (BOND_MODE(bond) == BOND_MODE_8023AD) {
 			struct aggregator *agg;
 
@@ -4171,8 +4204,6 @@ int bond_update_slave_arr(struct bonding
 		}
 		if (!bond_slave_can_tx(slave))
 			continue;
-		if (skipslave == slave)
-			continue;
 
 		slave_dbg(bond->dev, slave->dev, "Adding slave to tx hash array[%d]\n",
 			  usable_slaves->count);
@@ -4180,14 +4211,17 @@ int bond_update_slave_arr(struct bonding
 		usable_slaves->arr[usable_slaves->count++] = slave;
 	}
 
-	old_usable_slaves = rtnl_dereference(bond->usable_slaves);
-	rcu_assign_pointer(bond->usable_slaves, usable_slaves);
-	if (old_usable_slaves)
-		kfree_rcu(old_usable_slaves, rcu);
+	bond_set_slave_arr(bond, usable_slaves, all_slaves);
+	return ret;
 out:
-	if (ret != 0 && skipslave)
+	if (ret != 0 && skipslave) {
+		bond_skip_slave(rtnl_dereference(bond->all_slaves),
+				skipslave);
 		bond_skip_slave(rtnl_dereference(bond->usable_slaves),
 				skipslave);
+	}
+	kfree_rcu(all_slaves, rcu);
+	kfree_rcu(usable_slaves, rcu);
 
 	return ret;
 }
@@ -4494,9 +4528,9 @@ void bond_setup(struct net_device *bond_
 static void bond_uninit(struct net_device *bond_dev)
 {
 	struct bonding *bond = netdev_priv(bond_dev);
+	struct bond_up_slave *usable, *all;
 	struct list_head *iter;
 	struct slave *slave;
-	struct bond_up_slave *arr;
 
 	bond_netpoll_cleanup(bond_dev);
 
@@ -4505,10 +4539,16 @@ static void bond_uninit(struct net_devic
 		__bond_release_one(bond_dev, slave->dev, true, true);
 	netdev_info(bond_dev, "Released all slaves\n");
 
-	arr = rtnl_dereference(bond->usable_slaves);
-	if (arr) {
+	usable = rtnl_dereference(bond->usable_slaves);
+	if (usable) {
 		RCU_INIT_POINTER(bond->usable_slaves, NULL);
-		kfree_rcu(arr, rcu);
+		kfree_rcu(usable, rcu);
+	}
+
+	all = rtnl_dereference(bond->all_slaves);
+	if (all) {
+		RCU_INIT_POINTER(bond->all_slaves, NULL);
+		kfree_rcu(all, rcu);
 	}
 
 	list_del(&bond->bond_list);
--- a/include/net/bonding.h
+++ b/include/net/bonding.h
@@ -200,7 +200,8 @@ struct bonding {
 	struct   slave __rcu *curr_active_slave;
 	struct   slave __rcu *current_arp_slave;
 	struct   slave __rcu *primary_slave;
-	struct   bond_up_slave __rcu *usable_slaves; /* Array of usable slaves */
+	struct   bond_up_slave __rcu *usable_slaves;
+	struct   bond_up_slave __rcu *all_slaves;
 	bool     force_primary;
 	s32      slave_cnt; /* never change this value outside the attach/detach wrappers */
 	int     (*recv_probe)(const struct sk_buff *, struct bonding *,