mac80211: allow configure_filter callback to sleep

Over time, a whole bunch of drivers have come up
with their own scheme to delay the configure_filter
operation to a workqueue. To be able to simplify
things, allow configure_filter to sleep, and add
a new prepare_multicast callback that drivers that
need the multicast address list implement. This new
callback must be atomic, but most drivers either
don't care or just calculate a hash which can be
done atomically and then uploaded to the hardware
non-atomically.

A cursory look suggests that at76c50x-usb, ar9170,
mwl8k (which is actually very broken now), rt2x00,
wl1251, wl1271 and zd1211 should make use of this
new capability.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 28 insertions, 14 deletions

diff --git a/drivers/net/wireless/adm8211.c b/drivers/net/wireless/adm8211.c
index 5695911bc602..b80f514877d8 100644
--- a/drivers/net/wireless/adm8211.c
+++ b/drivers/net/wireless/adm8211.c
@@ -1328,16 +1328,39 @@ static void adm8211_bss_info_changed(struct ieee80211_hw *dev,
         }
 }
 
+static u64 adm8211_prepare_multicast(struct ieee80211_hw *hw,
+                                     int mc_count, struct dev_addr_list *mclist)
+{
+        unsigned int bit_nr, i;
+        u32 mc_filter[2];
+
+        mc_filter[1] = mc_filter[0] = 0;
+
+        for (i = 0; i < mc_count; i++) {
+                if (!mclist)
+                        break;
+                bit_nr = ether_crc(ETH_ALEN, mclist->dmi_addr) >> 26;
+
+                bit_nr &= 0x3F;
+                mc_filter[bit_nr >> 5] |= 1 << (bit_nr & 31);
+                mclist = mclist->next;
+        }
+
+        return mc_filter[0] | ((u64)(mc_filter[1]) << 32);
+}
+
 static void adm8211_configure_filter(struct ieee80211_hw *dev,
                                      unsigned int changed_flags,
                                      unsigned int *total_flags,
-                                     int mc_count, struct dev_mc_list *mclist)
+                                     u64 multicast)
 {
         static const u8 bcast[ETH_ALEN] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
         struct adm8211_priv *priv = dev->priv;
-        unsigned int bit_nr, new_flags;
+        unsigned int new_flags;
         u32 mc_filter[2];
-        int i;
+
+        mc_filter[0] = multicast;
+        mc_filter[1] = multicast >> 32;
 
         new_flags = 0;
 
@@ -1346,23 +1369,13 @@ static void adm8211_configure_filter(struct ieee80211_hw *dev,
                 priv->nar |= ADM8211_NAR_PR;
                 priv->nar &= ~ADM8211_NAR_MM;
                 mc_filter[1] = mc_filter[0] = ~0;
-        } else if ((*total_flags & FIF_ALLMULTI) || (mc_count > 32)) {
+        } else if (*total_flags & FIF_ALLMULTI || multicast == ~(0ULL)) {
                 new_flags |= FIF_ALLMULTI;
                 priv->nar &= ~ADM8211_NAR_PR;
                 priv->nar |= ADM8211_NAR_MM;
                 mc_filter[1] = mc_filter[0] = ~0;
         } else {
                 priv->nar &= ~(ADM8211_NAR_MM | ADM8211_NAR_PR);
-                mc_filter[1] = mc_filter[0] = 0;
-                for (i = 0; i < mc_count; i++) {
-                        if (!mclist)
-                                break;
-                        bit_nr = ether_crc(ETH_ALEN, mclist->dmi_addr) >> 26;
-
-                        bit_nr &= 0x3F;
-                        mc_filter[bit_nr >> 5] |= 1 << (bit_nr & 31);
-                        mclist = mclist->next;
-                }
         }
 
         ADM8211_IDLE_RX();
@@ -1757,6 +1770,7 @@ static const struct ieee80211_ops adm8211_ops = {
         .remove_interface       = adm8211_remove_interface,
         .config                 = adm8211_config,
         .bss_info_changed       = adm8211_bss_info_changed,
+        .prepare_multicast      = adm8211_prepare_multicast,
         .configure_filter       = adm8211_configure_filter,
         .get_stats              = adm8211_get_stats,
         .get_tx_stats           = adm8211_get_tx_stats,