[VLAN]: Avoid a 4-order allocation.

This patch splits the vlan_group struct into a multi-allocated struct. On
x86_64, the size of the original struct is a little more than 32KB, causing
a 4-order allocation, which is prune to problems caused by buddy-system
external fragmentation conditions.

I couldn't just use vmalloc() because vfree() cannot be called in the
softirq context of the RCU callback.

Signed-off-by: Dan Aloni <da-x@monatomic.org>
Acked-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 13 insertions, 12 deletions

diff --git a/drivers/s390/net/qeth_main.c b/drivers/s390/net/qeth_main.c
index 2257e45594b3..d8a86f5af379 100644
--- a/drivers/s390/net/qeth_main.c
+++ b/drivers/s390/net/qeth_main.c
@@ -3654,7 +3654,7 @@ qeth_verify_vlan_dev(struct net_device *dev, struct qeth_card *card)
 		return rc;
 
 	for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++){
-		if (vg->vlan_devices[i] == dev){
+		if (vlan_group_get_device(vg, i) == dev){
 			rc = QETH_VLAN_CARD;
 			break;
 		}
@@ -5261,7 +5261,7 @@ qeth_free_vlan_addresses4(struct qeth_card *card, unsigned short vid)
 	QETH_DBF_TEXT(trace, 4, "frvaddr4");
 
 	rcu_read_lock();
-	in_dev = __in_dev_get_rcu(card->vlangrp->vlan_devices[vid]);
+	in_dev = __in_dev_get_rcu(vlan_group_get_device(card->vlangrp, vid));
 	if (!in_dev)
 		goto out;
 	for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
@@ -5288,7 +5288,7 @@ qeth_free_vlan_addresses6(struct qeth_card *card, unsigned short vid)
 
 	QETH_DBF_TEXT(trace, 4, "frvaddr6");
 
-	in6_dev = in6_dev_get(card->vlangrp->vlan_devices[vid]);
+	in6_dev = in6_dev_get(vlan_group_get_device(card->vlangrp, vid));
 	if (!in6_dev)
 		return;
 	for (ifa = in6_dev->addr_list; ifa; ifa = ifa->lst_next){
@@ -5360,7 +5360,7 @@ qeth_layer2_process_vlans(struct qeth_card *card, int clear)
 	if (!card->vlangrp)
 		return;
 	for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
-		if (card->vlangrp->vlan_devices[i] == NULL)
+		if (vlan_group_get_device(card->vlangrp, i) == NULL)
 			continue;
 		if (clear)
 			qeth_layer2_send_setdelvlan(card, i, IPA_CMD_DELVLAN);
@@ -5398,8 +5398,7 @@ qeth_vlan_rx_kill_vid(struct net_device *dev, unsigned short vid)
 	spin_lock_irqsave(&card->vlanlock, flags);
 	/* unregister IP addresses of vlan device */
 	qeth_free_vlan_addresses(card, vid);
-	if (card->vlangrp)
-		card->vlangrp->vlan_devices[vid] = NULL;
+	vlan_group_set_device(card->vlangrp, vid, NULL);
 	spin_unlock_irqrestore(&card->vlanlock, flags);
 	if (card->options.layer2)
 		qeth_layer2_send_setdelvlan(card, vid, IPA_CMD_DELVLAN);
@@ -5662,10 +5661,11 @@ qeth_add_vlan_mc(struct qeth_card *card)
 
 	vg = card->vlangrp;
 	for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
-		if (vg->vlan_devices[i] == NULL ||
-		    !(vg->vlan_devices[i]->flags & IFF_UP))
+		struct net_device *netdev = vlan_group_get_device(vg, i);
+		if (netdev == NULL ||
+		    !(netdev->flags & IFF_UP))
 			continue;
-		in_dev = in_dev_get(vg->vlan_devices[i]);
+		in_dev = in_dev_get(netdev);
 		if (!in_dev)
 			continue;
 		read_lock(&in_dev->mc_list_lock);
@@ -5749,10 +5749,11 @@ qeth_add_vlan_mc6(struct qeth_card *card)
 
 	vg = card->vlangrp;
 	for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
-		if (vg->vlan_devices[i] == NULL ||
-		    !(vg->vlan_devices[i]->flags & IFF_UP))
+		struct net_device *netdev = vlan_group_get_device(vg, i);
+		if (netdev == NULL ||
+		    !(netdev->flags & IFF_UP))
 			continue;
-		in_dev = in6_dev_get(vg->vlan_devices[i]);
+		in_dev = in6_dev_get(netdev);
 		if (!in_dev)
 			continue;
 		read_lock(&in_dev->lock);