[RFC v3 6/8] wifi: mac80211: extend ifcomb check functions for multi-radio

[Karthikeyan Periyasamy]

On 6/7/2024 3:52 PM, Felix Fietkau wrote:
> On 07.06.24 12:07, Karthikeyan Periyasamy wrote:
>>
>>
>> On 6/6/2024 11:37 PM, Felix Fietkau wrote:
>>> Add support for counting global and per-radio max/current number of
>>> channels, as well as checking radio-specific interface combinations.
>>>
>>> Signed-off-by: Felix Fietkau <nbd at nbd.name>
>>> ---
>>>   net/mac80211/cfg.c         |   7 +-
>>>   net/mac80211/chan.c        |  17 +++--
>>>   net/mac80211/ibss.c        |   2 +-
>>>   net/mac80211/ieee80211_i.h |   6 +-
>>>   net/mac80211/iface.c       |   2 +-
>>>   net/mac80211/util.c        | 131 
>>> +++++++++++++++++++++++++++-----------
>>>   6 files changed, 116 insertions(+), 49 deletions(-)
>>>
>>> diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
>>> index 62119e957cd8..950b7b72f0b8 100644
>>> --- a/net/mac80211/cfg.c
>>> +++ b/net/mac80211/cfg.c
>>> @@ -263,7 +263,7 @@ static int ieee80211_start_p2p_device(struct 
>>> wiphy *wiphy,
>>>       lockdep_assert_wiphy(sdata->local->hw.wiphy);
>>> -    ret = ieee80211_check_combinations(sdata, NULL, 0, 0);
>>> +    ret = ieee80211_check_combinations(sdata, NULL, 0, 0, -1);
>>>       if (ret < 0)
>>>           return ret;
>>> @@ -285,7 +285,7 @@ static int ieee80211_start_nan(struct wiphy *wiphy,
>>>       lockdep_assert_wiphy(sdata->local->hw.wiphy);
>>> -    ret = ieee80211_check_combinations(sdata, NULL, 0, 0);
>>> +    ret = ieee80211_check_combinations(sdata, NULL, 0, 0, -1);
>>>       if (ret < 0)
>>>           return ret;
>>> @@ -4001,7 +4001,7 @@ __ieee80211_channel_switch(struct wiphy *wiphy, 
>>> struct net_device *dev,
>>>           goto out;
>>>       /* if reservation is invalid then this will fail */
>>> -    err = ieee80211_check_combinations(sdata, NULL, chanctx->mode, 0);
>>> +    err = ieee80211_check_combinations(sdata, NULL, chanctx->mode, 
>>> 0, -1);
>>
>> Once we reach the global limit, all the -1 passing caller get fail
>> becuase the iface check param (existing and new) is validated against
>> the global limit. since global limt as a sort of union of all per-radio
>> limits.
>>
>> Ex:
>> Global iface = 6 (Radio iface 2GHz:4, 5GHz:4, 6GHz:6)
>>
>>
>> So far 6 iface created (Radio iface 2GHz:2, 5GHz:3, 6GHz:1)
>>
>> In this case, new iface creation get fail because caller uses
>> ieee80211_check_combinations() with -1 as radio idx, so it checked
>> against global limit
> 
> Use the sum of the number of interfaces from each radio instead of the 
> maximum.

Oh, then legacy user have misconception of the global interfaces 
advertised and try to fail for the allowed limits.

-- 
Karthikeyan Periyasamy
--
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