linux/drivers/net/wireless/ath9k/virtual.c

/*
 * Copyright (c) 2008-2009 Atheros Communications Inc.
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include "ath9k.h"

struct ath9k_vif_iter_data {
	int count;
	u8 *addr;
};

static void ath9k_vif_iter(void *data, u8 *mac, struct ieee80211_vif *vif)
{
	struct ath9k_vif_iter_data *iter_data = data;
	u8 *nbuf;

	nbuf = krealloc(iter_data->addr, (iter_data->count + 1) * ETH_ALEN,
			GFP_ATOMIC);
	if (nbuf == NULL)
		return;

	memcpy(nbuf + iter_data->count * ETH_ALEN, mac, ETH_ALEN);
	iter_data->addr = nbuf;
	iter_data->count++;
}

void ath9k_set_bssid_mask(struct ieee80211_hw *hw)
{
	struct ath_wiphy *aphy = hw->priv;
	struct ath_softc *sc = aphy->sc;
	struct ath9k_vif_iter_data iter_data;
	int i, j;
	u8 mask[ETH_ALEN];

	/*
	 * Add primary MAC address even if it is not in active use since it
	 * will be configured to the hardware as the starting point and the
	 * BSSID mask will need to be changed if another address is active.
	 */
	iter_data.addr = kmalloc(ETH_ALEN, GFP_ATOMIC);
	if (iter_data.addr) {
		memcpy(iter_data.addr, sc->sc_ah->macaddr, ETH_ALEN);
		iter_data.count = 1;
	} else
		iter_data.count = 0;

	/* Get list of all active MAC addresses */
	spin_lock_bh(&sc->wiphy_lock);
	ieee80211_iterate_active_interfaces_atomic(sc->hw, ath9k_vif_iter,
						   &iter_data);
	for (i = 0; i < sc->num_sec_wiphy; i++) {
		if (sc->sec_wiphy[i] == NULL)
			continue;
		ieee80211_iterate_active_interfaces_atomic(
			sc->sec_wiphy[i]->hw, ath9k_vif_iter, &iter_data);
	}
	spin_unlock_bh(&sc->wiphy_lock);

	/* Generate an address mask to cover all active addresses */
	memset(mask, 0, ETH_ALEN);
	for (i = 0; i < iter_data.count; i++) {
		u8 *a1 = iter_data.addr + i * ETH_ALEN;
		for (j = i + 1; j < iter_data.count; j++) {
			u8 *a2 = iter_data.addr + j * ETH_ALEN;
			mask[0] |= a1[0] ^ a2[0];
			mask[1] |= a1[1] ^ a2[1];
			mask[2] |= a1[2] ^ a2[2];
			mask[3] |= a1[3] ^ a2[3];
			mask[4] |= a1[4] ^ a2[4];
			mask[5] |= a1[5] ^ a2[5];
		}
	}

	kfree(iter_data.addr);

	/* Invert the mask and configure hardware */
	sc->bssidmask[0] = ~mask[0];
	sc->bssidmask[1] = ~mask[1];
	sc->bssidmask[2] = ~mask[2];
	sc->bssidmask[3] = ~mask[3];
	sc->bssidmask[4] = ~mask[4];
	sc->bssidmask[5] = ~mask[5];

	ath9k_hw_setbssidmask(sc);
}

int ath9k_wiphy_add(struct ath_softc *sc)
{
	int i, error;
	struct ath_wiphy *aphy;
	struct ieee80211_hw *hw;
	u8 addr[ETH_ALEN];

	hw = ieee80211_alloc_hw(sizeof(struct ath_wiphy), &ath9k_ops);
	if (hw == NULL)
		return -ENOMEM;

	spin_lock_bh(&sc->wiphy_lock);
	for (i = 0; i < sc->num_sec_wiphy; i++) {
		if (sc->sec_wiphy[i] == NULL)
			break;
	}

	if (i == sc->num_sec_wiphy) {
		/* No empty slot available; increase array length */
		struct ath_wiphy **n;
		n = krealloc(sc->sec_wiphy,
			     (sc->num_sec_wiphy + 1) *
			     sizeof(struct ath_wiphy *),
			     GFP_ATOMIC);
		if (n == NULL) {
			spin_unlock_bh(&sc->wiphy_lock);
			ieee80211_free_hw(hw);
			return -ENOMEM;
		}
		n[i] = NULL;
		sc->sec_wiphy = n;
		sc->num_sec_wiphy++;
	}

	SET_IEEE80211_DEV(hw, sc->dev);

	aphy = hw->priv;
	aphy->sc = sc;
	aphy->hw = hw;
	sc->sec_wiphy[i] = aphy;
	spin_unlock_bh(&sc->wiphy_lock);

	memcpy(addr, sc->sc_ah->macaddr, ETH_ALEN);
	addr[0] |= 0x02; /* Locally managed address */
	/*
	 * XOR virtual wiphy index into the least significant bits to generate
	 * a different MAC address for each virtual wiphy.
	 */
	addr[5] ^= i & 0xff;
	addr[4] ^= (i & 0xff00) >> 8;
	addr[3] ^= (i & 0xff0000) >> 16;

	SET_IEEE80211_PERM_ADDR(hw, addr);

	ath_set_hw_capab(sc, hw);

	error = ieee80211_register_hw(hw);

	return error;
}

int ath9k_wiphy_del(struct ath_wiphy *aphy)
{
	struct ath_softc *sc = aphy->sc;
	int i;

	spin_lock_bh(&sc->wiphy_lock);
	for (i = 0; i < sc->num_sec_wiphy; i++) {
		if (aphy == sc->sec_wiphy[i]) {
			sc->sec_wiphy[i] = NULL;
			spin_unlock_bh(&sc->wiphy_lock);
			ieee80211_unregister_hw(aphy->hw);
			ieee80211_free_hw(aphy->hw);
			return 0;
		}
	}
	spin_unlock_bh(&sc->wiphy_lock);
	return -ENOENT;
}