igc: Fix NFC rules restoration

When network interface is brought up, the driver re-enables the NFC
rules previously configured. However, this is done in reverse order
the rules were added and hardware filters are configured differently.

For example, consider the following rules:

$ ethtool -N eth0 flow-type ether dst 00:00:00:00:00:AA queue 0
$ ethtool -N eth0 flow-type ether dst 00:00:00:00:00:BB queue 1
$ ethtool -N eth0 flow-type ether dst 00:00:00:00:00:CC queue 2
$ ethtool -N eth0 flow-type ether dst 00:00:00:00:00:DD queue 3

RAL/RAH registers are configure so filter index 1 has address ending
with AA, filter index 2 has address ending in BB, and so on.

If we bring the interface down and up again, RAL/RAH registers are
configured so filter index 1 has address ending in DD, filter index 2
has CC, and so on. IOW, in reverse order we had before bringing the
interface down.

This issue can be fixed by traversing adapter->nfc_rule_list in
backwards when restoring the rules. Since hlist doesn't support
backwards traversal, this patch replaces it by list_head and fixes
igc_restore_nfc_rules() accordingly.

Signed-off-by: Andre Guedes <andre.guedes@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

diff --git a/drivers/net/ethernet/intel/igc/igc.h b/drivers/net/ethernet/intel/igc/igc.h
index ae7d480..76bc3a5 100644 (file)
--- a/drivers/net/ethernet/intel/igc/igc.h
+++ b/drivers/net/ethernet/intel/igc/igc.h
@@ -191,7 +191,7 @@ struct igc_adapter {
         * nfc_rule_lock.
         */
        spinlock_t nfc_rule_lock;
-       struct hlist_head nfc_rule_list;
+       struct list_head nfc_rule_list;
        unsigned int nfc_rule_count;
 
        u8 rss_indir_tbl[IGC_RETA_SIZE];
@@ -461,7 +461,7 @@ struct igc_nfc_filter {
 };
 
 struct igc_nfc_rule {
-       struct hlist_node nfc_node;
+       struct list_head list;
        struct igc_nfc_filter filter;
        u32 location;
        u16 action;

diff --git a/drivers/net/ethernet/intel/igc/igc_ethtool.c b/drivers/net/ethernet/intel/igc/igc_ethtool.c
index f01a7ec..a90493f 100644 (file)
--- a/drivers/net/ethernet/intel/igc/igc_ethtool.c
+++ b/drivers/net/ethernet/intel/igc/igc_ethtool.c
@@ -941,7 +941,7 @@ static int igc_ethtool_get_nfc_rule(struct igc_adapter *adapter,
 
        spin_lock(&adapter->nfc_rule_lock);
 
-       hlist_for_each_entry(rule, &adapter->nfc_rule_list, nfc_node) {
+       list_for_each_entry(rule, &adapter->nfc_rule_list, list) {
                if (fsp->location <= rule->location)
                        break;
        }
@@ -997,7 +997,7 @@ static int igc_ethtool_get_nfc_rules(struct igc_adapter *adapter,
 
        spin_lock(&adapter->nfc_rule_lock);
 
-       hlist_for_each_entry(rule, &adapter->nfc_rule_list, nfc_node) {
+       list_for_each_entry(rule, &adapter->nfc_rule_list, list) {
                if (cnt == cmd->rule_cnt) {
                        spin_unlock(&adapter->nfc_rule_lock);
                        return -EMSGSIZE;
@@ -1261,7 +1261,7 @@ static int igc_ethtool_update_nfc_rule(struct igc_adapter *adapter,
        parent = NULL;
        rule = NULL;
 
-       hlist_for_each_entry(rule, &adapter->nfc_rule_list, nfc_node) {
+       list_for_each_entry(rule, &adapter->nfc_rule_list, list) {
                /* hash found, or no matching entry */
                if (rule->location >= location)
                        break;
@@ -1272,7 +1272,7 @@ static int igc_ethtool_update_nfc_rule(struct igc_adapter *adapter,
        if (rule && rule->location == location) {
                err = igc_disable_nfc_rule(adapter, rule);
 
-               hlist_del(&rule->nfc_node);
+               list_del(&rule->list);
                kfree(rule);
                adapter->nfc_rule_count--;
        }
@@ -1283,11 +1283,8 @@ static int igc_ethtool_update_nfc_rule(struct igc_adapter *adapter,
        if (!input)
                return err;
 
-       /* add filter to the list */
-       if (parent)
-               hlist_add_behind(&input->nfc_node, &parent->nfc_node);
-       else
-               hlist_add_head(&input->nfc_node, &adapter->nfc_rule_list);
+       list_add(&input->list, parent ? &parent->list :
+                                       &adapter->nfc_rule_list);
 
        /* update counts */
        adapter->nfc_rule_count++;
@@ -1298,7 +1295,7 @@ static int igc_ethtool_update_nfc_rule(struct igc_adapter *adapter,
 static void igc_ethtool_init_nfc_rule(struct igc_nfc_rule *rule,
                                      const struct ethtool_rx_flow_spec *fsp)
 {
-       INIT_HLIST_NODE(&rule->nfc_node);
+       INIT_LIST_HEAD(&rule->list);
 
        rule->action = fsp->ring_cookie;
        rule->location = fsp->location;
@@ -1362,7 +1359,7 @@ static int igc_ethtool_check_nfc_rule(struct igc_adapter *adapter,
                return -EOPNOTSUPP;
        }
 
-       hlist_for_each_entry(tmp, &adapter->nfc_rule_list, nfc_node) {
+       list_for_each_entry(tmp, &adapter->nfc_rule_list, list) {
                if (!memcmp(&rule->filter, &tmp->filter,
                            sizeof(rule->filter))) {
                        netdev_dbg(dev, "Rule already exists\n");

diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c
index acb8dfd..cf76e2c 100644 (file)
--- a/drivers/net/ethernet/intel/igc/igc_main.c
+++ b/drivers/net/ethernet/intel/igc/igc_main.c
@@ -2180,7 +2180,7 @@ static void igc_restore_nfc_rules(struct igc_adapter *adapter)
 
        spin_lock(&adapter->nfc_rule_lock);
 
-       hlist_for_each_entry(rule, &adapter->nfc_rule_list, nfc_node)
+       list_for_each_entry_reverse(rule, &adapter->nfc_rule_list, list)
                igc_enable_nfc_rule(adapter, rule);
 
        spin_unlock(&adapter->nfc_rule_lock);
@@ -3419,6 +3419,9 @@ static int igc_sw_init(struct igc_adapter *adapter)
        adapter->min_frame_size = ETH_ZLEN + ETH_FCS_LEN;
 
        spin_lock_init(&adapter->nfc_rule_lock);
+       INIT_LIST_HEAD(&adapter->nfc_rule_list);
+       adapter->nfc_rule_count = 0;
+
        spin_lock_init(&adapter->stats64_lock);
        /* Assume MSI-X interrupts, will be checked during IRQ allocation */
        adapter->flags |= IGC_FLAG_HAS_MSIX;
@@ -3651,7 +3654,7 @@ static void igc_nfc_rule_exit(struct igc_adapter *adapter)
 
        spin_lock(&adapter->nfc_rule_lock);
 
-       hlist_for_each_entry(rule, &adapter->nfc_rule_list, nfc_node)
+       list_for_each_entry(rule, &adapter->nfc_rule_list, list)
                igc_disable_nfc_rule(adapter, rule);
 
        spin_unlock(&adapter->nfc_rule_lock);
@@ -3826,14 +3829,13 @@ static int igc_set_features(struct net_device *netdev,
                return 0;
 
        if (!(features & NETIF_F_NTUPLE)) {
-               struct hlist_node *node2;
-               struct igc_nfc_rule *rule;
+               struct igc_nfc_rule *rule, *tmp;
 
                spin_lock(&adapter->nfc_rule_lock);
-               hlist_for_each_entry_safe(rule, node2,
-                                         &adapter->nfc_rule_list, nfc_node) {
+               list_for_each_entry_safe(rule, tmp,
+                                        &adapter->nfc_rule_list, list) {
                        igc_disable_nfc_rule(adapter, rule);
-                       hlist_del(&rule->nfc_node);
+                       list_del(&rule->list);
                        kfree(rule);
                }
                spin_unlock(&adapter->nfc_rule_lock);