diff options
| -rw-r--r-- | include/net/mac80211.h | 47 | ||||
| -rw-r--r-- | net/mac80211/util.c | 140 |
2 files changed, 187 insertions, 0 deletions
diff --git a/include/net/mac80211.h b/include/net/mac80211.h index 531785f5819e..f838af816b56 100644 --- a/include/net/mac80211.h +++ b/include/net/mac80211.h @@ -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 */ diff --git a/net/mac80211/util.c b/net/mac80211/util.c index ed93504d24b8..df00f1978a77 100644 --- a/net/mac80211/util.c +++ b/net/mac80211/util.c @@ -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); |