Commit a7022e65 authored by Felix Fietkau's avatar Felix Fietkau Committed by Johannes Berg

mac80211: add helper functions for tracking P2P NoA state

Signed-off-by: default avatarFelix Fietkau <nbd@openwrt.org>
Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
parent 34a3740d
......@@ -4652,4 +4652,51 @@ bool ieee80211_tx_prepare_skb(struct ieee80211_hw *hw,
struct ieee80211_vif *vif, struct sk_buff *skb,
int band, struct ieee80211_sta **sta);
/**
* struct ieee80211_noa_data - holds temporary data for tracking P2P NoA state
*
* @next_tsf: TSF timestamp of the next absent state change
* @has_next_tsf: next absent state change event pending
*
* @absent: descriptor bitmask, set if GO is currently absent
*
* private:
*
* @count: count fields from the NoA descriptors
* @desc: adjusted data from the NoA
*/
struct ieee80211_noa_data {
u32 next_tsf;
bool has_next_tsf;
u8 absent;
u8 count[IEEE80211_P2P_NOA_DESC_MAX];
struct {
u32 start;
u32 duration;
u32 interval;
} desc[IEEE80211_P2P_NOA_DESC_MAX];
};
/**
* ieee80211_parse_p2p_noa - initialize NoA tracking data from P2P IE
*
* @attr: P2P NoA IE
* @data: NoA tracking data
* @tsf: current TSF timestamp
*
* Return: number of successfully parsed descriptors
*/
int ieee80211_parse_p2p_noa(const struct ieee80211_p2p_noa_attr *attr,
struct ieee80211_noa_data *data, u32 tsf);
/**
* ieee80211_update_p2p_noa - get next pending P2P GO absent state change
*
* @data: NoA tracking data
* @tsf: current TSF timestamp
*/
void ieee80211_update_p2p_noa(struct ieee80211_noa_data *data, u32 tsf);
#endif /* MAC80211_H */
......@@ -2594,3 +2594,143 @@ int ieee80211_cs_headroom(struct ieee80211_local *local,
return headroom;
}
static bool
ieee80211_extend_noa_desc(struct ieee80211_noa_data *data, u32 tsf, int i)
{
s32 end = data->desc[i].start + data->desc[i].duration - (tsf + 1);
int skip;
if (end > 0)
return false;
/* End time is in the past, check for repetitions */
skip = DIV_ROUND_UP(-end, data->desc[i].interval);
if (data->count[i] < 255) {
if (data->count[i] <= skip) {
data->count[i] = 0;
return false;
}
data->count[i] -= skip;
}
data->desc[i].start += skip * data->desc[i].interval;
return true;
}
static bool
ieee80211_extend_absent_time(struct ieee80211_noa_data *data, u32 tsf,
s32 *offset)
{
bool ret = false;
int i;
for (i = 0; i < IEEE80211_P2P_NOA_DESC_MAX; i++) {
s32 cur;
if (!data->count[i])
continue;
if (ieee80211_extend_noa_desc(data, tsf + *offset, i))
ret = true;
cur = data->desc[i].start - tsf;
if (cur > *offset)
continue;
cur = data->desc[i].start + data->desc[i].duration - tsf;
if (cur > *offset)
*offset = cur;
}
return ret;
}
static u32
ieee80211_get_noa_absent_time(struct ieee80211_noa_data *data, u32 tsf)
{
s32 offset = 0;
int tries = 0;
/*
* arbitrary limit, used to avoid infinite loops when combined NoA
* descriptors cover the full time period.
*/
int max_tries = 5;
ieee80211_extend_absent_time(data, tsf, &offset);
do {
if (!ieee80211_extend_absent_time(data, tsf, &offset))
break;
tries++;
} while (tries < max_tries);
return offset;
}
void ieee80211_update_p2p_noa(struct ieee80211_noa_data *data, u32 tsf)
{
u32 next_offset = BIT(31) - 1;
int i;
data->absent = 0;
data->has_next_tsf = false;
for (i = 0; i < IEEE80211_P2P_NOA_DESC_MAX; i++) {
s32 start;
if (!data->count[i])
continue;
ieee80211_extend_noa_desc(data, tsf, i);
start = data->desc[i].start - tsf;
if (start <= 0)
data->absent |= BIT(i);
if (next_offset > start)
next_offset = start;
data->has_next_tsf = true;
}
if (data->absent)
next_offset = ieee80211_get_noa_absent_time(data, tsf);
data->next_tsf = tsf + next_offset;
}
EXPORT_SYMBOL(ieee80211_update_p2p_noa);
int ieee80211_parse_p2p_noa(const struct ieee80211_p2p_noa_attr *attr,
struct ieee80211_noa_data *data, u32 tsf)
{
int ret = 0;
int i;
memset(data, 0, sizeof(*data));
for (i = 0; i < IEEE80211_P2P_NOA_DESC_MAX; i++) {
const struct ieee80211_p2p_noa_desc *desc = &attr->desc[i];
if (!desc->count || !desc->duration)
continue;
data->count[i] = desc->count;
data->desc[i].start = le32_to_cpu(desc->start_time);
data->desc[i].duration = le32_to_cpu(desc->duration);
data->desc[i].interval = le32_to_cpu(desc->interval);
if (data->count[i] > 1 &&
data->desc[i].interval < data->desc[i].duration)
continue;
ieee80211_extend_noa_desc(data, tsf, i);
ret++;
}
if (ret)
ieee80211_update_p2p_noa(data, tsf);
return ret;
}
EXPORT_SYMBOL(ieee80211_parse_p2p_noa);
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