Skip to content

Commit

Permalink
mac80211: add support for mcs masks
Browse files Browse the repository at this point in the history
* Handle MCS masks set by the user.
* Match rates provided by the rate control algorithm to the mask set,
  also in HT mode, and switch back to legacy mode if necessary.
* add debugfs files to observate the rate selection

Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Mathias Kretschmer <mathias.kretschmer@fokus.fraunhofer.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
  • Loading branch information
Simon Wunderlich authored and John W. Linville committed Jan 30, 2012
1 parent 24db78c commit 1946841
Show file tree
Hide file tree
Showing 7 changed files with 168 additions and 9 deletions.
1 change: 1 addition & 0 deletions include/net/mac80211.h
Original file line number Diff line number Diff line change
Expand Up @@ -3551,6 +3551,7 @@ struct ieee80211_tx_rate_control {
bool rts, short_preamble;
u8 max_rate_idx;
u32 rate_idx_mask;
u8 rate_idx_mcs_mask[IEEE80211_HT_MCS_MASK_LEN];
bool bss;
};

Expand Down
5 changes: 4 additions & 1 deletion net/mac80211/cfg.c
Original file line number Diff line number Diff line change
Expand Up @@ -1902,8 +1902,11 @@ static int ieee80211_set_bitrate_mask(struct wiphy *wiphy,
return ret;
}

for (i = 0; i < IEEE80211_NUM_BANDS; i++)
for (i = 0; i < IEEE80211_NUM_BANDS; i++) {
sdata->rc_rateidx_mask[i] = mask->control[i].legacy;
memcpy(sdata->rc_rateidx_mcs_mask[i], mask->control[i].mcs,
sizeof(mask->control[i].mcs));
}

return 0;
}
Expand Down
34 changes: 34 additions & 0 deletions net/mac80211/debugfs_netdev.c
Original file line number Diff line number Diff line change
Expand Up @@ -87,6 +87,21 @@ static ssize_t ieee80211_if_fmt_##name( \
#define IEEE80211_IF_FMT_SIZE(name, field) \
IEEE80211_IF_FMT(name, field, "%zd\n")

#define IEEE80211_IF_FMT_HEXARRAY(name, field) \
static ssize_t ieee80211_if_fmt_##name( \
const struct ieee80211_sub_if_data *sdata, \
char *buf, int buflen) \
{ \
char *p = buf; \
int i; \
for (i = 0; i < sizeof(sdata->field); i++) { \
p += scnprintf(p, buflen + buf - p, "%.2x ", \
sdata->field[i]); \
} \
p += scnprintf(p, buflen + buf - p, "\n"); \
return p - buf; \
}

#define IEEE80211_IF_FMT_ATOMIC(name, field) \
static ssize_t ieee80211_if_fmt_##name( \
const struct ieee80211_sub_if_data *sdata, \
Expand Down Expand Up @@ -148,6 +163,11 @@ IEEE80211_IF_FILE(rc_rateidx_mask_2ghz, rc_rateidx_mask[IEEE80211_BAND_2GHZ],
HEX);
IEEE80211_IF_FILE(rc_rateidx_mask_5ghz, rc_rateidx_mask[IEEE80211_BAND_5GHZ],
HEX);
IEEE80211_IF_FILE(rc_rateidx_mcs_mask_2ghz,
rc_rateidx_mcs_mask[IEEE80211_BAND_2GHZ], HEXARRAY);
IEEE80211_IF_FILE(rc_rateidx_mcs_mask_5ghz,
rc_rateidx_mcs_mask[IEEE80211_BAND_5GHZ], HEXARRAY);

IEEE80211_IF_FILE(flags, flags, HEX);
IEEE80211_IF_FILE(state, state, LHEX);
IEEE80211_IF_FILE(channel_type, vif.bss_conf.channel_type, DEC);
Expand Down Expand Up @@ -442,6 +462,8 @@ static void add_sta_files(struct ieee80211_sub_if_data *sdata)
DEBUGFS_ADD(channel_type);
DEBUGFS_ADD(rc_rateidx_mask_2ghz);
DEBUGFS_ADD(rc_rateidx_mask_5ghz);
DEBUGFS_ADD(rc_rateidx_mcs_mask_2ghz);
DEBUGFS_ADD(rc_rateidx_mcs_mask_5ghz);

DEBUGFS_ADD(bssid);
DEBUGFS_ADD(aid);
Expand All @@ -459,6 +481,8 @@ static void add_ap_files(struct ieee80211_sub_if_data *sdata)
DEBUGFS_ADD(channel_type);
DEBUGFS_ADD(rc_rateidx_mask_2ghz);
DEBUGFS_ADD(rc_rateidx_mask_5ghz);
DEBUGFS_ADD(rc_rateidx_mcs_mask_2ghz);
DEBUGFS_ADD(rc_rateidx_mcs_mask_5ghz);

DEBUGFS_ADD(num_sta_authorized);
DEBUGFS_ADD(num_sta_ps);
Expand All @@ -469,6 +493,12 @@ static void add_ap_files(struct ieee80211_sub_if_data *sdata)

static void add_ibss_files(struct ieee80211_sub_if_data *sdata)
{
DEBUGFS_ADD(channel_type);
DEBUGFS_ADD(rc_rateidx_mask_2ghz);
DEBUGFS_ADD(rc_rateidx_mask_5ghz);
DEBUGFS_ADD(rc_rateidx_mcs_mask_2ghz);
DEBUGFS_ADD(rc_rateidx_mcs_mask_5ghz);

DEBUGFS_ADD_MODE(tsf, 0600);
}

Expand All @@ -480,6 +510,8 @@ static void add_wds_files(struct ieee80211_sub_if_data *sdata)
DEBUGFS_ADD(channel_type);
DEBUGFS_ADD(rc_rateidx_mask_2ghz);
DEBUGFS_ADD(rc_rateidx_mask_5ghz);
DEBUGFS_ADD(rc_rateidx_mcs_mask_2ghz);
DEBUGFS_ADD(rc_rateidx_mcs_mask_5ghz);

DEBUGFS_ADD(peer);
}
Expand All @@ -492,6 +524,8 @@ static void add_vlan_files(struct ieee80211_sub_if_data *sdata)
DEBUGFS_ADD(channel_type);
DEBUGFS_ADD(rc_rateidx_mask_2ghz);
DEBUGFS_ADD(rc_rateidx_mask_5ghz);
DEBUGFS_ADD(rc_rateidx_mcs_mask_2ghz);
DEBUGFS_ADD(rc_rateidx_mcs_mask_5ghz);
}

static void add_monitor_files(struct ieee80211_sub_if_data *sdata)
Expand Down
1 change: 1 addition & 0 deletions net/mac80211/ieee80211_i.h
Original file line number Diff line number Diff line change
Expand Up @@ -646,6 +646,7 @@ struct ieee80211_sub_if_data {

/* bitmap of allowed (non-MCS) rate indexes for rate control */
u32 rc_rateidx_mask[IEEE80211_NUM_BANDS];
u8 rc_rateidx_mcs_mask[IEEE80211_NUM_BANDS][IEEE80211_HT_MCS_MASK_LEN];

union {
struct ieee80211_if_ap ap;
Expand Down
7 changes: 7 additions & 0 deletions net/mac80211/iface.c
Original file line number Diff line number Diff line change
Expand Up @@ -1181,6 +1181,13 @@ int ieee80211_if_add(struct ieee80211_local *local, const char *name,
sband = local->hw.wiphy->bands[i];
sdata->rc_rateidx_mask[i] =
sband ? (1 << sband->n_bitrates) - 1 : 0;
if (sband)
memcpy(sdata->rc_rateidx_mcs_mask[i],
sband->ht_cap.mcs.rx_mask,
sizeof(sdata->rc_rateidx_mcs_mask[i]));
else
memset(sdata->rc_rateidx_mcs_mask[i], 0,
sizeof(sdata->rc_rateidx_mcs_mask[i]));
}

/* setup type-dependent data */
Expand Down
124 changes: 116 additions & 8 deletions net/mac80211/rate.c
Original file line number Diff line number Diff line change
Expand Up @@ -289,8 +289,8 @@ bool rate_control_send_low(struct ieee80211_sta *sta,
}
EXPORT_SYMBOL(rate_control_send_low);

static void rate_idx_match_mask(struct ieee80211_tx_rate *rate,
int n_bitrates, u32 mask)
static bool rate_idx_match_legacy_mask(struct ieee80211_tx_rate *rate,
int n_bitrates, u32 mask)
{
int j;

Expand All @@ -299,7 +299,7 @@ static void rate_idx_match_mask(struct ieee80211_tx_rate *rate,
if (mask & (1 << j)) {
/* Okay, found a suitable rate. Use it. */
rate->idx = j;
return;
return true;
}
}

Expand All @@ -308,6 +308,112 @@ static void rate_idx_match_mask(struct ieee80211_tx_rate *rate,
if (mask & (1 << j)) {
/* Okay, found a suitable rate. Use it. */
rate->idx = j;
return true;
}
}
return false;
}

static bool rate_idx_match_mcs_mask(struct ieee80211_tx_rate *rate,
u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN])
{
int i, j;
int ridx, rbit;

ridx = rate->idx / 8;
rbit = rate->idx % 8;

/* sanity check */
if (ridx < 0 || ridx > IEEE80211_HT_MCS_MASK_LEN)
return false;

/* See whether the selected rate or anything below it is allowed. */
for (i = ridx; i >= 0; i--) {
for (j = rbit; j >= 0; j--)
if (mcs_mask[i] & BIT(j)) {
rate->idx = i * 8 + j;
return true;
}
rbit = 7;
}

/* Try to find a higher rate that would be allowed */
ridx = (rate->idx + 1) / 8;
rbit = (rate->idx + 1) % 8;

for (i = ridx; i < IEEE80211_HT_MCS_MASK_LEN; i++) {
for (j = rbit; j < 8; j++)
if (mcs_mask[i] & BIT(j)) {
rate->idx = i * 8 + j;
return true;
}
rbit = 0;
}
return false;
}



static void rate_idx_match_mask(struct ieee80211_tx_rate *rate,
struct ieee80211_tx_rate_control *txrc,
u32 mask,
u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN])
{
struct ieee80211_tx_rate alt_rate;

/* handle HT rates */
if (rate->flags & IEEE80211_TX_RC_MCS) {
if (rate_idx_match_mcs_mask(rate, mcs_mask))
return;

/* also try the legacy rates. */
alt_rate.idx = 0;
/* keep protection flags */
alt_rate.flags = rate->flags &
(IEEE80211_TX_RC_USE_RTS_CTS |
IEEE80211_TX_RC_USE_CTS_PROTECT |
IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
alt_rate.count = rate->count;
if (rate_idx_match_legacy_mask(&alt_rate,
txrc->sband->n_bitrates,
mask)) {
*rate = alt_rate;
return;
}
} else {
struct sk_buff *skb = txrc->skb;
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
__le16 fc;

/* handle legacy rates */
if (rate_idx_match_legacy_mask(rate, txrc->sband->n_bitrates,
mask))
return;

/* if HT BSS, and we handle a data frame, also try HT rates */
if (txrc->bss_conf->channel_type == NL80211_CHAN_NO_HT)
return;

fc = hdr->frame_control;
if (!ieee80211_is_data(fc))
return;

alt_rate.idx = 0;
/* keep protection flags */
alt_rate.flags = rate->flags &
(IEEE80211_TX_RC_USE_RTS_CTS |
IEEE80211_TX_RC_USE_CTS_PROTECT |
IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
alt_rate.count = rate->count;

alt_rate.flags |= IEEE80211_TX_RC_MCS;

if ((txrc->bss_conf->channel_type == NL80211_CHAN_HT40MINUS) ||
(txrc->bss_conf->channel_type == NL80211_CHAN_HT40PLUS))
alt_rate.flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;

if (rate_idx_match_mcs_mask(&alt_rate, mcs_mask)) {
*rate = alt_rate;
return;
}
}
Expand All @@ -331,6 +437,7 @@ void rate_control_get_rate(struct ieee80211_sub_if_data *sdata,
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb);
int i;
u32 mask;
u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN];

if (sta) {
ista = &sta->sta;
Expand All @@ -354,10 +461,14 @@ void rate_control_get_rate(struct ieee80211_sub_if_data *sdata,
* the common case.
*/
mask = sdata->rc_rateidx_mask[info->band];
memcpy(mcs_mask, sdata->rc_rateidx_mcs_mask[info->band],
sizeof(mcs_mask));
if (mask != (1 << txrc->sband->n_bitrates) - 1) {
if (sta) {
/* Filter out rates that the STA does not support */
mask &= sta->sta.supp_rates[info->band];
for (i = 0; i < sizeof(mcs_mask); i++)
mcs_mask[i] &= sta->sta.ht_cap.mcs.rx_mask[i];
}
/*
* Make sure the rate index selected for each TX rate is
Expand All @@ -368,11 +479,8 @@ void rate_control_get_rate(struct ieee80211_sub_if_data *sdata,
/* Skip invalid rates */
if (info->control.rates[i].idx < 0)
break;
/* Rate masking supports only legacy rates for now */
if (info->control.rates[i].flags & IEEE80211_TX_RC_MCS)
continue;
rate_idx_match_mask(&info->control.rates[i],
txrc->sband->n_bitrates, mask);
rate_idx_match_mask(&info->control.rates[i], txrc,
mask, mcs_mask);
}
}

Expand Down
5 changes: 5 additions & 0 deletions net/mac80211/tx.c
Original file line number Diff line number Diff line change
Expand Up @@ -635,6 +635,9 @@ ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx)
txrc.max_rate_idx = -1;
else
txrc.max_rate_idx = fls(txrc.rate_idx_mask) - 1;
memcpy(txrc.rate_idx_mcs_mask,
tx->sdata->rc_rateidx_mcs_mask[tx->channel->band],
sizeof(txrc.rate_idx_mcs_mask));
txrc.bss = (tx->sdata->vif.type == NL80211_IFTYPE_AP ||
tx->sdata->vif.type == NL80211_IFTYPE_MESH_POINT ||
tx->sdata->vif.type == NL80211_IFTYPE_ADHOC);
Expand Down Expand Up @@ -2431,6 +2434,8 @@ struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
txrc.max_rate_idx = -1;
else
txrc.max_rate_idx = fls(txrc.rate_idx_mask) - 1;
memcpy(txrc.rate_idx_mcs_mask, sdata->rc_rateidx_mcs_mask[band],
sizeof(txrc.rate_idx_mcs_mask));
txrc.bss = true;
rate_control_get_rate(sdata, NULL, &txrc);

Expand Down

0 comments on commit 1946841

Please sign in to comment.