A 6GHz AP can decide to transmit Beacon, Broadcast probe response
and FILS discovery frames in a non-HT duplicate PPDU when
operating in non 20MHz Bandwidth to enhance its discoverability.
(IEEE Std 802.11ax‐2021-26.17.2.2)
Add changes to configure 6GHz non-HT duplicate beacon transmission
based on Duplicate Beacon subfield of 6GHz Operation Information
field of the HE Operation element in Beacon.
Signed-off-by: Rameshkumar Sundaram <[email protected]>
---
include/net/mac80211.h | 1 +
net/mac80211/cfg.c | 17 +++++++++++++++++
2 files changed, 18 insertions(+)
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index c50221d..a4b1efb 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -704,6 +704,7 @@ struct ieee80211_bss_conf {
struct cfg80211_he_bss_color he_bss_color;
struct ieee80211_fils_discovery fils_discovery;
u32 unsol_bcast_probe_resp_interval;
+ bool he_6g_nonht_dup_beacon_set;
bool s1g;
struct cfg80211_bitrate_mask beacon_tx_rate;
enum ieee80211_ap_reg_power power_type;
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 87a2080..9b6f55e 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -997,6 +997,9 @@ static int ieee80211_assign_beacon(struct ieee80211_sub_if_data *sdata,
struct beacon_data *new, *old;
int new_head_len, new_tail_len;
int size, err;
+ const struct element *cap;
+ struct ieee80211_he_operation *he_oper;
+ const struct ieee80211_he_6ghz_oper *he_6ghz_oper;
u32 changed = BSS_CHANGED_BEACON;
old = sdata_dereference(sdata->u.ap.beacon, sdata);
@@ -1084,6 +1087,20 @@ static int ieee80211_assign_beacon(struct ieee80211_sub_if_data *sdata,
changed |= BSS_CHANGED_FTM_RESPONDER;
}
+ cap = cfg80211_find_ext_elem(WLAN_EID_EXT_HE_OPERATION,
+ params->tail, params->tail_len);
+ if (cap && cap->datalen >= sizeof(*he_oper) + 1) {
+ he_oper = (void *)(cap->data + 1);
+ he_6ghz_oper = ieee80211_he_6ghz_oper(he_oper);
+ if (he_6ghz_oper) {
+ sdata->vif.bss_conf.he_6g_nonht_dup_beacon_set = false;
+ if (u8_get_bits(he_6ghz_oper->control,
+ IEEE80211_HE_6GHZ_OPER_CTRL_DUP_BEACON)) {
+ sdata->vif.bss_conf.he_6g_nonht_dup_beacon_set = true;
+ }
+ }
+ }
+
rcu_assign_pointer(sdata->u.ap.beacon, new);
if (old)
--
2.7.4
Hi,
Couple of notes below:
> @@ -704,6 +704,7 @@ struct ieee80211_bss_conf {
> struct cfg80211_he_bss_color he_bss_color;
> struct ieee80211_fils_discovery fils_discovery;
> u32 unsol_bcast_probe_resp_interval;
> + bool he_6g_nonht_dup_beacon_set;
This is missing documentation.
> + cap = cfg80211_find_ext_elem(WLAN_EID_EXT_HE_OPERATION,
> + params->tail, params->tail_len);
> + if (cap && cap->datalen >= sizeof(*he_oper) + 1) {
> + he_oper = (void *)(cap->data + 1);
> + he_6ghz_oper = ieee80211_he_6ghz_oper(he_oper);
> + if (he_6ghz_oper) {
> + sdata->vif.bss_conf.he_6g_nonht_dup_beacon_set = false;
> + if (u8_get_bits(he_6ghz_oper->control,
> + IEEE80211_HE_6GHZ_OPER_CTRL_DUP_BEACON)) {
> + sdata->vif.bss_conf.he_6g_nonht_dup_beacon_set = true;
> + }
no braces needed there, and no u8_get_bits() either, you can just & ?
> + }
> + }
I am wondering though if this should even be detected from the HE
operation element itself, rather than from the beacon rate settings that
are separate in nl80211?
johannes
> -----Original Message-----
> From: Johannes Berg <[email protected]>
> Sent: Friday, March 11, 2022 4:33 PM
> To: Rameshkumar Sundaram (QUIC) <[email protected]>
> Cc: [email protected]; [email protected]
> Subject: Re: [PATCH 1/2] mac80211: add support to configure 6GHz non-ht
> duplicate transmission
>
> Hi,
>
> Couple of notes below:
>
> > @@ -704,6 +704,7 @@ struct ieee80211_bss_conf {
> > struct cfg80211_he_bss_color he_bss_color;
> > struct ieee80211_fils_discovery fils_discovery;
> > u32 unsol_bcast_probe_resp_interval;
> > + bool he_6g_nonht_dup_beacon_set;
>
> This is missing documentation.
Thanks, will add it in next patch
>
> > + cap = cfg80211_find_ext_elem(WLAN_EID_EXT_HE_OPERATION,
> > + params->tail, params->tail_len);
> > + if (cap && cap->datalen >= sizeof(*he_oper) + 1) {
> > + he_oper = (void *)(cap->data + 1);
> > + he_6ghz_oper = ieee80211_he_6ghz_oper(he_oper);
> > + if (he_6ghz_oper) {
> > + sdata->vif.bss_conf.he_6g_nonht_dup_beacon_set =
> false;
> > + if (u8_get_bits(he_6ghz_oper->control,
> > +
> IEEE80211_HE_6GHZ_OPER_CTRL_DUP_BEACON)) {
> > + sdata-
> >vif.bss_conf.he_6g_nonht_dup_beacon_set = true;
> > + }
>
> no braces needed there, and no u8_get_bits() either, you can just & ?
Sure, I remember I got sparse warnings last time without this (also took reference from net/mac80211/util.c ieee80211_chandef_he_6ghz_oper()), will send v2 with 'just &' anyway.
>
> > + }
> > + }
>
> I am wondering though if this should even be detected from the HE
> operation element itself, rather than from the beacon rate settings that are
> separate in nl80211?
This is a BW dependent bit in HE Oper IE and user space can switch BW (CSA/chan switch scenarios).
Which can call assign_beacon directly, Hence adding the logic here to cover all Beacon change cases.
>
> johannes
On Mon, 2022-03-21 at 05:12 +0000, Rameshkumar Sundaram (QUIC) wrote:
>
> >
> > I am wondering though if this should even be detected from the HE
> > operation element itself, rather than from the beacon rate settings
> > that are
> > separate in nl80211?
> This is a BW dependent bit in HE Oper IE and user space can switch BW
> (CSA/chan switch scenarios).
> Which can call assign_beacon directly, Hence adding the logic here to
> cover all Beacon change cases.
>
Yeah but still ... why do we take it from the content rather than adding
a control for it?
johannes
> -----Original Message-----
> From: Johannes Berg <[email protected]>
> Sent: Monday, March 21, 2022 2:28 PM
> To: Rameshkumar Sundaram (QUIC) <[email protected]>
> Cc: [email protected]; [email protected]
> Subject: Re: [PATCH 1/2] mac80211: add support to configure 6GHz non-ht
> duplicate transmission
>
> On Mon, 2022-03-21 at 05:12 +0000, Rameshkumar Sundaram (QUIC) wrote:
> >
> > >
> > > I am wondering though if this should even be detected from the HE
> > > operation element itself, rather than from the beacon rate settings
> > > that are separate in nl80211?
> > This is a BW dependent bit in HE Oper IE and user space can switch BW
> > (CSA/chan switch scenarios).
> > Which can call assign_beacon directly, Hence adding the logic here to
> > cover all Beacon change cases.
> >
>
> Yeah but still ... why do we take it from the content rather than adding a
> control for it?
So, Suggestion here is to add a new NL attribute to carry the information from user space for
START_AP and SET_BEACON NL commands and use it here, is that understanding correct ?
>
> johannes
On Tue, 2022-03-22 at 13:50 +0000, Rameshkumar Sundaram (QUIC) wrote:
> >
> So, Suggestion here is to add a new NL attribute to carry the
> information from user space for
> START_AP and SET_BEACON NL commands and use it here, is that
> understanding correct ?
>
Well, I was thinking it would reasonably come with the beacon rate, i.e.
as a new attribute like NL80211_TXRATE_DUP?
johannes
> -----Original Message-----
> From: Johannes Berg <[email protected]>
> Sent: Tuesday, March 22, 2022 8:34 PM
> To: Rameshkumar Sundaram (QUIC) <[email protected]>
> Cc: [email protected]; [email protected]
> Subject: Re: [PATCH 1/2] mac80211: add support to configure 6GHz non-ht
> duplicate transmission
>
> WARNING: This email originated from outside of Qualcomm. Please be wary
> of any links or attachments, and do not enable macros.
>
> On Tue, 2022-03-22 at 13:50 +0000, Rameshkumar Sundaram (QUIC) wrote:
> > >
> > So, Suggestion here is to add a new NL attribute to carry the
> > information from user space for START_AP and SET_BEACON NL commands
> > and use it here, is that understanding correct ?
> >
>
> Well, I was thinking it would reasonably come with the beacon rate, i.e.
> as a new attribute like NL80211_TXRATE_DUP?
Sorry not getting this, you mean hostapd would need to send new set of rates for this configuration ?
The expectation is that user-space will set this bit in HE oper IE only if legacy rates are present in beacon or basic rates.
>
> johannes
On Sun, 2022-04-17 at 14:30 +0000, Rameshkumar Sundaram (QUIC) wrote:
> >
> > Well, I was thinking it would reasonably come with the beacon rate,
> > i.e.
> > as a new attribute like NL80211_TXRATE_DUP?
> Sorry not getting this, you mean hostapd would need to send new set of
> rates for this configuration ?
> The expectation is that user-space will set this bit in HE oper IE
> only if legacy rates are present in beacon or basic rates.
>
?
I don't understand.
The point is - you're setting the bit in the beacon that indicates "I'm
transmitting it as duplicate", right?
But you're also using that bit to actually configure it to do (non-HT)
duplicate transmissions.
But fundamentally, those two things aren't really related, are they? Why
shouldn't you be - at least theoretically - be able to configure it for
duplicate transmission (or not) regardless of the bit in the beacon?
To me it seems "do duplicate transmission" is a property of the *rate*
you want to use to transmit, not really necessarily a property of the
*content* of the frame you're transmitting.
johannes