rt2x00: Add per-interface structure

Rework the interface handling. Delete the interface structure
and replace it with a per-interface structure. This changes the
way rt2x00 handles the active interface drastically.

Copy ieee80211_bss_conf to the this rt2x00_intf structure during
the bss_info_changed() callback function. This will allow us to
reference it later, and removes the requirement for the device flag
SHORT_PREAMBLE flag which is interface specific.

Drivers receive the option to give the maximum number of virtual
interfaces the device can handle. Virtual interface support:
rt2400pci: 1 sta or 1 ap, * monitor interfaces
rt2500pci: 1 sta or 1 ap, * monitor interfaces
rt2500usb: 1 sta or 1 ap, * monitor interfaces
rt61pci: 1 sta or 4 ap, * monitor interfaces
rt73usb: 1 sta or 4 ap, * monitor interfaces

At the moment none of the drivers support AP and STA interfaces
simultaneously, this is a hardware limitation so future support
will be very unlikely.

Each interface structure receives its dedicated beacon entry,
with this we can easily work with beaconing while multiple master
mode interfaces are currently active.

The configuration handlers for the MAC, BSSID and type are
often called together since they all belong to the interface
configuration. Merge the 3 configuration calls and cleanup
the API between rt2x00lib and the drivers. While we are cleaning
up the interface configuration anyway, we might as well clean up
the configuration handler as well.

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 101 insertions, 51 deletions

diff --git a/drivers/net/wireless/rt2x00/rt2x00mac.c b/drivers/net/wireless/rt2x00/rt2x00mac.c
index f08c151ee4ba..65a2bcd18aa1 100644
--- a/drivers/net/wireless/rt2x00/rt2x00mac.c
+++ b/drivers/net/wireless/rt2x00/rt2x00mac.c
@@ -52,11 +52,11 @@ static int rt2x00mac_tx_rts_cts(struct rt2x00_dev *rt2x00dev,
         skb_put(skb, size);
 
         if (control->flags & IEEE80211_TXCTL_USE_CTS_PROTECT)
-                ieee80211_ctstoself_get(rt2x00dev->hw, rt2x00dev->interface.id,
+                ieee80211_ctstoself_get(rt2x00dev->hw, control->vif,
                                         frag_skb->data, frag_skb->len, control,
                                         (struct ieee80211_cts *)(skb->data));
         else
-                ieee80211_rts_get(rt2x00dev->hw, rt2x00dev->interface.id,
+                ieee80211_rts_get(rt2x00dev->hw, control->vif,
                                   frag_skb->data, frag_skb->len, control,
                                   (struct ieee80211_rts *)(skb->data));
 
@@ -162,19 +162,67 @@ int rt2x00mac_add_interface(struct ieee80211_hw *hw,
                             struct ieee80211_if_init_conf *conf)
 {
         struct rt2x00_dev *rt2x00dev = hw->priv;
-        struct interface *intf = &rt2x00dev->interface;
+        struct rt2x00_intf *intf = vif_to_intf(conf->vif);
+        struct data_queue *queue =
+            rt2x00queue_get_queue(rt2x00dev, IEEE80211_TX_QUEUE_BEACON);
+        struct queue_entry *entry = NULL;
+        unsigned int i;
 
         /*
-         * Don't allow interfaces to be added while
-         * either the device has disappeared or when
-         * another interface is already present.
+         * Don't allow interfaces to be added
+         * the device has disappeared.
          */
         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags) ||
-            is_interface_present(intf))
+            !test_bit(DEVICE_STARTED, &rt2x00dev->flags))
+                return -ENODEV;
+
+        /*
+         * When we don't support mixed interfaces (a combination
+         * of sta and ap virtual interfaces) then we can only
+         * add this interface when the rival interface count is 0.
+         */
+        if (!test_bit(DRIVER_SUPPORT_MIXED_INTERFACES, &rt2x00dev->flags) &&
+            ((conf->type == IEEE80211_IF_TYPE_AP && rt2x00dev->intf_sta_count) ||
+             (conf->type != IEEE80211_IF_TYPE_AP && rt2x00dev->intf_ap_count)))
+                return -ENOBUFS;
+
+        /*
+         * Check if we exceeded the maximum amount of supported interfaces.
+         */
+        if ((conf->type == IEEE80211_IF_TYPE_AP &&
+             rt2x00dev->intf_ap_count >= rt2x00dev->ops->max_ap_intf) ||
+            (conf->type != IEEE80211_IF_TYPE_AP &&
+             rt2x00dev->intf_sta_count >= rt2x00dev->ops->max_sta_intf))
+                return -ENOBUFS;
+
+        /*
+         * Loop through all beacon queues to find a free
+         * entry. Since there are as much beacon entries
+         * as the maximum interfaces, this search shouldn't
+         * fail.
+         */
+        for (i = 0; i < queue->limit; i++) {
+                entry = &queue->entries[i];
+                if (!__test_and_set_bit(ENTRY_BCN_ASSIGNED, &entry->flags))
+                        break;
+        }
+
+        if (unlikely(i == queue->limit))
                 return -ENOBUFS;
 
-        intf->id = conf->vif;
-        intf->type = conf->type;
+        /*
+         * We are now absolutely sure the interface can be created,
+         * increase interface count and start initialization.
+         */
+
+        if (conf->type == IEEE80211_IF_TYPE_AP)
+                rt2x00dev->intf_ap_count++;
+        else
+                rt2x00dev->intf_sta_count++;
+
+        spin_lock_init(&intf->lock);
+        intf->beacon = entry;
+
         if (conf->type == IEEE80211_IF_TYPE_AP)
                 memcpy(&intf->bssid, conf->mac_addr, ETH_ALEN);
         memcpy(&intf->mac, conf->mac_addr, ETH_ALEN);
@@ -184,8 +232,7 @@ int rt2x00mac_add_interface(struct ieee80211_hw *hw,
          * has been initialized. Otherwise the device can reset
          * the MAC registers.
          */
-        rt2x00lib_config_mac_addr(rt2x00dev, intf->mac);
-        rt2x00lib_config_type(rt2x00dev, conf->type);
+        rt2x00lib_config_intf(rt2x00dev, intf, conf->type, intf->mac, NULL);
 
         return 0;
 }
@@ -195,7 +242,7 @@ void rt2x00mac_remove_interface(struct ieee80211_hw *hw,
                                 struct ieee80211_if_init_conf *conf)
 {
         struct rt2x00_dev *rt2x00dev = hw->priv;
-        struct interface *intf = &rt2x00dev->interface;
+        struct rt2x00_intf *intf = vif_to_intf(conf->vif);
 
         /*
          * Don't allow interfaces to be remove while
@@ -203,21 +250,27 @@ void rt2x00mac_remove_interface(struct ieee80211_hw *hw,
          * no interface is present.
          */
         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags) ||
-            !is_interface_present(intf))
+            (conf->type == IEEE80211_IF_TYPE_AP && !rt2x00dev->intf_ap_count) ||
+            (conf->type != IEEE80211_IF_TYPE_AP && !rt2x00dev->intf_sta_count))
                 return;
 
-        intf->id = NULL;
-        intf->type = IEEE80211_IF_TYPE_INVALID;
-        memset(&intf->bssid, 0x00, ETH_ALEN);
-        memset(&intf->mac, 0x00, ETH_ALEN);
+        if (conf->type == IEEE80211_IF_TYPE_AP)
+                rt2x00dev->intf_ap_count--;
+        else
+                rt2x00dev->intf_sta_count--;
+
+        /*
+         * Release beacon entry so it is available for
+         * new interfaces again.
+         */
+        __clear_bit(ENTRY_BCN_ASSIGNED, &intf->beacon->flags);
 
         /*
          * Make sure the bssid and mac address registers
          * are cleared to prevent false ACKing of frames.
          */
-        rt2x00lib_config_mac_addr(rt2x00dev, intf->mac);
-        rt2x00lib_config_bssid(rt2x00dev, intf->bssid);
-        rt2x00lib_config_type(rt2x00dev, intf->type);
+        rt2x00lib_config_intf(rt2x00dev, intf,
+                              IEEE80211_IF_TYPE_INVALID, NULL, NULL);
 }
 EXPORT_SYMBOL_GPL(rt2x00mac_remove_interface);
 
@@ -262,7 +315,7 @@ int rt2x00mac_config_interface(struct ieee80211_hw *hw,
                                struct ieee80211_if_conf *conf)
 {
         struct rt2x00_dev *rt2x00dev = hw->priv;
-        struct interface *intf = &rt2x00dev->interface;
+        struct rt2x00_intf *intf = vif_to_intf(vif);
         int status;
 
         /*
@@ -272,12 +325,7 @@ int rt2x00mac_config_interface(struct ieee80211_hw *hw,
         if (!test_bit(DEVICE_PRESENT, &rt2x00dev->flags))
                 return 0;
 
-        /*
-         * If the given type does not match the configured type,
-         * there has been a problem.
-         */
-        if (conf->type != intf->type)
-                return -EINVAL;
+        spin_lock(&intf->lock);
 
         /*
          * If the interface does not work in master mode,
@@ -286,7 +334,9 @@ int rt2x00mac_config_interface(struct ieee80211_hw *hw,
          */
         if (conf->type != IEEE80211_IF_TYPE_AP)
                 memcpy(&intf->bssid, conf->bssid, ETH_ALEN);
-        rt2x00lib_config_bssid(rt2x00dev, intf->bssid);
+        rt2x00lib_config_intf(rt2x00dev, intf, conf->type, NULL, intf->bssid);
+
+        spin_unlock(&intf->lock);
 
         /*
          * We only need to initialize the beacon when master mode is enabled.
@@ -342,35 +392,35 @@ void rt2x00mac_bss_info_changed(struct ieee80211_hw *hw,
                                 u32 changes)
 {
         struct rt2x00_dev *rt2x00dev = hw->priv;
-        int short_preamble;
-        int ack_timeout;
-        int ack_consume_time;
-        int difs;
-        int preamble;
+        struct rt2x00_intf *intf = vif_to_intf(vif);
 
         /*
-         * We only support changing preamble mode.
+         * When the association status has changed we must reset the link
+         * tuner counter. This is because some drivers determine if they
+         * should perform link tuning based on the number of seconds
+         * while associated or not associated.
          */
-        if (!(changes & BSS_CHANGED_ERP_PREAMBLE))
-                return;
-
-        short_preamble = bss_conf->use_short_preamble;
-        preamble = bss_conf->use_short_preamble ?
-                                SHORT_PREAMBLE : PREAMBLE;
+        if (changes & BSS_CHANGED_ASSOC) {
+                rt2x00dev->link.count = 0;
 
-        difs = (hw->conf.flags & IEEE80211_CONF_SHORT_SLOT_TIME) ?
-                SHORT_DIFS : DIFS;
-        ack_timeout = difs + PLCP + preamble + get_duration(ACK_SIZE, 10);
-
-        ack_consume_time = SIFS + PLCP + preamble + get_duration(ACK_SIZE, 10);
+                if (bss_conf->assoc)
+                        rt2x00dev->intf_associated++;
+                else
+                        rt2x00dev->intf_associated--;
+        }
 
-        if (short_preamble)
-                __set_bit(CONFIG_SHORT_PREAMBLE, &rt2x00dev->flags);
-        else
-                __clear_bit(CONFIG_SHORT_PREAMBLE, &rt2x00dev->flags);
+        /*
+         * When the preamble mode has changed, we should perform additional
+         * configuration steps. For all other changes we are already done.
+         */
+        if (changes & BSS_CHANGED_ERP_PREAMBLE) {
+                rt2x00lib_config_preamble(rt2x00dev, intf,
+                                          bss_conf->use_short_preamble);
 
-        rt2x00dev->ops->lib->config_preamble(rt2x00dev, short_preamble,
-                                             ack_timeout, ack_consume_time);
+                spin_lock(&intf->lock);
+                memcpy(&intf->conf, bss_conf, sizeof(*bss_conf));
+                spin_unlock(&intf->lock);
+        }
 }
 EXPORT_SYMBOL_GPL(rt2x00mac_bss_info_changed);