cfg80211: keep track of supported interface modes

It is obviously good for userspace to know up front which
interface modes a given piece of hardware might support (even
if adding such an interface might fail later because of
concurrency issues), so let's make cfg80211 aware of that.
For good measure, disallow adding interfaces in all other
modes so drivers don't forget to announce support for one mode
when they add it.

Signed-off-by: Johannes Berg <[e-mail]>
Signed-off-by: Stephen Blackheath <[e-mail]>
Signed-off-by: Ivo van Doorn <[e-mail]>
Signed-off-by: Luis R. Rodriguez <[e-mail]>
Signed-off-by: John W. Linville <[e-mail]>

drivers/net/wireless/adm8211.c

···
 	dev->extra_tx_headroom = sizeof(struct adm8211_tx_hdr);
 	/* dev->flags = IEEE80211_HW_RX_INCLUDES_FCS in promisc mode */
 	dev->flags = IEEE80211_HW_SIGNAL_UNSPEC;
+	dev->wiphy->interface_modes = BIT(NL80211_IFTYPE_STATION);
 
 	dev->channel_change_time = 1000;
 	dev->max_signal = 100;    /* FIXME: find better value */

drivers/net/wireless/ath5k/base.c

···
 	hw->flags = IEEE80211_HW_RX_INCLUDES_FCS |
 		    IEEE80211_HW_SIGNAL_DBM |
 		    IEEE80211_HW_NOISE_DBM;
+
+	hw->wiphy->interface_modes =
+		BIT(NL80211_IFTYPE_STATION) |
+		BIT(NL80211_IFTYPE_ADHOC) |
+		BIT(NL80211_IFTYPE_MESH_POINT);
+
 	hw->extra_tx_headroom = 2;
 	hw->channel_change_time = 5000;
 	sc = hw->priv;

drivers/net/wireless/ath9k/main.c

···
 		IEEE80211_HW_SIGNAL_DBM |
 		IEEE80211_HW_NOISE_DBM;
 
+	hw->wiphy->interface_modes =
+		BIT(NL80211_IFTYPE_AP) |
+		BIT(NL80211_IFTYPE_STATION) |
+		BIT(NL80211_IFTYPE_ADHOC);
+
 	SET_IEEE80211_DEV(hw, &pdev->dev);
 	pci_set_drvdata(pdev, hw);
 

drivers/net/wireless/b43/main.c

···
 		    IEEE80211_HW_SIGNAL_DBM |
 		    IEEE80211_HW_NOISE_DBM;
 
+	hw->wiphy->interface_modes =
+		BIT(NL80211_IFTYPE_AP) |
+		BIT(NL80211_IFTYPE_MESH_POINT) |
+		BIT(NL80211_IFTYPE_STATION) |
+		BIT(NL80211_IFTYPE_WDS) |
+		BIT(NL80211_IFTYPE_ADHOC);
+
 	hw->queues = b43_modparam_qos ? 4 : 1;
 	SET_IEEE80211_DEV(hw, dev->dev);
 	if (is_valid_ether_addr(sprom->et1mac))

drivers/net/wireless/b43legacy/main.c

···
 	hw->flags = IEEE80211_HW_RX_INCLUDES_FCS |
 		    IEEE80211_HW_SIGNAL_DBM |
 		    IEEE80211_HW_NOISE_DBM;
+	hw->wiphy->interface_modes =
+		BIT(NL80211_IFTYPE_AP) |
+		BIT(NL80211_IFTYPE_STATION) |
+		BIT(NL80211_IFTYPE_WDS) |
+		BIT(NL80211_IFTYPE_ADHOC);
 	hw->queues = 1; /* FIXME: hardware has more queues */
 	SET_IEEE80211_DEV(hw, dev->dev);
 	if (is_valid_ether_addr(sprom->et1mac))

drivers/net/wireless/iwlwifi/iwl-core.c

···
 	/* Tell mac80211 our characteristics */
 	hw->flags = IEEE80211_HW_SIGNAL_DBM |
 		    IEEE80211_HW_NOISE_DBM;
+	hw->wiphy->interface_modes =
+		BIT(NL80211_IFTYPE_AP) |
+		BIT(NL80211_IFTYPE_STATION) |
+		BIT(NL80211_IFTYPE_ADHOC);
 	/* Default value; 4 EDCA QOS priorities */
 	hw->queues = 4;
 	/* queues to support 11n aggregation */

drivers/net/wireless/iwlwifi/iwl3945-base.c

···
 	hw->flags = IEEE80211_HW_SIGNAL_DBM |
 		    IEEE80211_HW_NOISE_DBM;
 
+	hw->wiphy->interface_modes =
+		BIT(NL80211_IFTYPE_AP) |
+		BIT(NL80211_IFTYPE_STATION) |
+		BIT(NL80211_IFTYPE_ADHOC);
+
 	/* 4 EDCA QOS priorities */
 	hw->queues = 4;
 

drivers/net/wireless/mac80211_hwsim.c

···
 
 		hw->channel_change_time = 1;
 		hw->queues = 4;
+		hw->wiphy->interface_modes =
+			BIT(NL80211_IFTYPE_STATION) |
+			BIT(NL80211_IFTYPE_AP);
 		hw->ampdu_queues = 1;
 
 		memcpy(data->channels, hwsim_channels, sizeof(hwsim_channels));

drivers/net/wireless/p54/p54common.c

···
 	dev->flags = IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING | /* not sure */
 		     IEEE80211_HW_RX_INCLUDES_FCS |
 		     IEEE80211_HW_SIGNAL_UNSPEC;
+
+	dev->wiphy->interface_modes = BIT(NL80211_IFTYPE_STATION);
+
 	dev->channel_change_time = 1000;	/* TODO: find actual value */
 	dev->max_signal = 127;
 

drivers/net/wireless/rt2x00/rt2x00dev.c

···
 	 */
 	rt2x00dev->hw->vif_data_size = sizeof(struct rt2x00_intf);
 
+	rt2x00dev->hw->wiphy->interface_modes =
+	    BIT(NL80211_IFTYPE_AP) |
+	    BIT(NL80211_IFTYPE_STATION) |
+	    BIT(NL80211_IFTYPE_ADHOC);
+
 	/*
 	 * Let the driver probe the device to detect the capabilities.
 	 */

drivers/net/wireless/rtl8187_dev.c

···
 		dev->max_signal = 65;
 	}
 
+	dev->wiphy->interface_modes = BIT(NL80211_IFTYPE_STATION);
+
 	if ((id->driver_info == DEVICE_RTL8187) && priv->is_rtl8187b)
 		printk(KERN_INFO "rtl8187: inconsistency between id with OEM"
 		       " info!\n");

drivers/net/wireless/zd1211rw/zd_mac.c

···
 	hw->flags = IEEE80211_HW_RX_INCLUDES_FCS |
 		    IEEE80211_HW_SIGNAL_DB;
 
+	hw->wiphy->interface_modes =
+		BIT(NL80211_IFTYPE_MESH_POINT) |
+		BIT(NL80211_IFTYPE_STATION) |
+		BIT(NL80211_IFTYPE_ADHOC);
+
 	hw->max_signal = 100;
 	hw->queues = 1;
 	hw->extra_tx_headroom = sizeof(struct zd_ctrlset);

include/linux/nl80211.h

···
  * @NL80211_ATTR_HT_CAPABILITY: HT Capability information element (from
  *	association request when used with NL80211_CMD_NEW_STATION)
  *
+ * @NL80211_ATTR_SUPPORTED_IFTYPES: nested attribute containing all
+ *	supported interface types, each a flag attribute with the number
+ *	of the interface mode.
+ *
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
  */
···
 	NL80211_ATTR_BSS_SHORT_SLOT_TIME,
 
 	NL80211_ATTR_HT_CAPABILITY,
+
+	NL80211_ATTR_SUPPORTED_IFTYPES,
 
 	/* add attributes here, update the policy in nl80211.c */
 

include/net/wireless.h

···
 	/* permanent MAC address */
 	u8 perm_addr[ETH_ALEN];
 
+	/* Supported interface modes, OR together BIT(NL80211_IFTYPE_...) */
+	u16 interface_modes;
+
 	/* If multiple wiphys are registered and you're handed e.g.
 	 * a regular netdev with assigned ieee80211_ptr, you won't
 	 * know whether it points to a wiphy your driver has registered

net/mac80211/main.c

···
 		}
 	}
 
+	/* if low-level driver supports AP, we also support VLAN */
+	if (local->hw.wiphy->interface_modes & BIT(NL80211_IFTYPE_AP))
+		local->hw.wiphy->interface_modes |= BIT(NL80211_IFTYPE_AP_VLAN);
+
+	/* mac80211 always supports monitor */
+	local->hw.wiphy->interface_modes |= BIT(NL80211_IFTYPE_MONITOR);
+
 	result = wiphy_register(local->hw.wiphy);
 	if (result < 0)
 		return result;

net/wireless/core.c

···
 /*
  * This is the linux wireless configuration interface.
  *
- * Copyright 2006, 2007		Johannes Berg <[e-mail]>
+ * Copyright 2006-2008		Johannes Berg <[e-mail]>
  */
 
 #include <linux/if.h>
···
 	struct ieee80211_supported_band *sband;
 	bool have_band = false;
 	int i;
+	u16 ifmodes = wiphy->interface_modes;
+
+	/* sanity check ifmodes */
+	WARN_ON(!ifmodes);
+	ifmodes &= ((1 << __NL80211_IFTYPE_AFTER_LAST) - 1) & ~1;
+	if (WARN_ON(ifmodes != wiphy->interface_modes))
+		wiphy->interface_modes = ifmodes;
 
 	/* sanity check supported bands/channels */
 	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {

net/wireless/nl80211.c

···
 	struct nlattr *nl_bands, *nl_band;
 	struct nlattr *nl_freqs, *nl_freq;
 	struct nlattr *nl_rates, *nl_rate;
+	struct nlattr *nl_modes;
 	enum ieee80211_band band;
 	struct ieee80211_channel *chan;
 	struct ieee80211_rate *rate;
 	int i;
+	u16 ifmodes = dev->wiphy.interface_modes;
 
 	hdr = nl80211hdr_put(msg, pid, seq, flags, NL80211_CMD_NEW_WIPHY);
 	if (!hdr)
···
 
 	NLA_PUT_U32(msg, NL80211_ATTR_WIPHY, dev->idx);
 	NLA_PUT_STRING(msg, NL80211_ATTR_WIPHY_NAME, wiphy_name(&dev->wiphy));
+
+	nl_modes = nla_nest_start(msg, NL80211_ATTR_SUPPORTED_IFTYPES);
+	if (!nl_modes)
+		goto nla_put_failure;
+
+	i = 0;
+	while (ifmodes) {
+		if (ifmodes & 1)
+			NLA_PUT_FLAG(msg, i);
+		ifmodes >>= 1;
+		i++;
+	}
+
+	nla_nest_end(msg, nl_modes);
 
 	nl_bands = nla_nest_start(msg, NL80211_ATTR_WIPHY_BANDS);
 	if (!nl_bands)
···
 	ifindex = dev->ifindex;
 	dev_put(dev);
 
-	if (!drv->ops->change_virtual_intf) {
+	if (!drv->ops->change_virtual_intf ||
+	    !(drv->wiphy.interface_modes & (1 << type))) {
 		err = -EOPNOTSUPP;
 		goto unlock;
 	}
···
 	if (IS_ERR(drv))
 		return PTR_ERR(drv);
 
-	if (!drv->ops->add_virtual_intf) {
+	if (!drv->ops->add_virtual_intf ||
+	    !(drv->wiphy.interface_modes & (1 << type))) {
 		err = -EOPNOTSUPP;
 		goto unlock;
 	}