cfg80211/mac80211: Use more generic bitrate mask for rate control

Extend struct cfg80211_bitrate_mask to actually use a bitfield mask
instead of just a single fixed or maximum rate index. This change
itself does not modify the behavior (except for debugfs files), but it
prepares cfg80211 and mac80211 for a new nl80211 command for setting
which rates can be used in TX rate control.

Since frames are now going through the rate control algorithm
unconditionally, the internal IEEE80211_TX_INTFL_RCALGO flag can now
be removed. The RC implementations can use the rate_idx_mask value to
optimize their behavior if only a single rate is enabled.

The old max_rate_idx in struct ieee80211_tx_rate_control is maintained
(but commented as deprecated) for backwards compatibility with existing
RC implementations. Once these implementations have been updated to
use the more generic rate_idx_mask, the max_rate_idx value can be
removed.

Signed-off-by: Jouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 6 insertions, 2 deletions

diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index 264a6c9..fe140bf 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -856,8 +856,12 @@ int ieee80211_if_add(struct ieee80211_local *local, const char *name,
 
 	INIT_LIST_HEAD(&sdata->key_list);
 
-	sdata->force_unicast_rateidx = -1;
-	sdata->max_ratectrl_rateidx = -1;
+	for (i = 0; i < IEEE80211_NUM_BANDS; i++) {
+		struct ieee80211_supported_band *sband;
+		sband = local->hw.wiphy->bands[i];
+		sdata->rc_rateidx_mask[i] =
+			sband ? (1 << sband->n_bitrates) - 1 : 0;
+	}
 
 	/* setup type-dependent data */
 	ieee80211_setup_sdata(sdata, type);