linux/net/mac80211/chan.c
Michal Kazior 23a85b45cf mac80211: refactor set_channel_type
Split functionality for further reuse.

Will prevent code duplication when channel context
channel_type merging is introduced.

Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-09-06 17:55:00 +02:00

170 lines
3.7 KiB
C

/*
* mac80211 - channel management
*/
#include <linux/nl80211.h>
#include <net/cfg80211.h>
#include "ieee80211_i.h"
static enum ieee80211_chan_mode
__ieee80211_get_channel_mode(struct ieee80211_local *local,
struct ieee80211_sub_if_data *ignore)
{
struct ieee80211_sub_if_data *sdata;
lockdep_assert_held(&local->iflist_mtx);
list_for_each_entry(sdata, &local->interfaces, list) {
if (sdata == ignore)
continue;
if (!ieee80211_sdata_running(sdata))
continue;
switch (sdata->vif.type) {
case NL80211_IFTYPE_MONITOR:
continue;
case NL80211_IFTYPE_STATION:
if (!sdata->u.mgd.associated)
continue;
break;
case NL80211_IFTYPE_ADHOC:
if (!sdata->u.ibss.ssid_len)
continue;
if (!sdata->u.ibss.fixed_channel)
return CHAN_MODE_HOPPING;
break;
case NL80211_IFTYPE_AP_VLAN:
/* will also have _AP interface */
continue;
case NL80211_IFTYPE_AP:
if (!sdata->u.ap.beacon)
continue;
break;
case NL80211_IFTYPE_MESH_POINT:
if (!sdata->wdev.mesh_id_len)
continue;
break;
default:
break;
}
return CHAN_MODE_FIXED;
}
return CHAN_MODE_UNDEFINED;
}
enum ieee80211_chan_mode
ieee80211_get_channel_mode(struct ieee80211_local *local,
struct ieee80211_sub_if_data *ignore)
{
enum ieee80211_chan_mode mode;
mutex_lock(&local->iflist_mtx);
mode = __ieee80211_get_channel_mode(local, ignore);
mutex_unlock(&local->iflist_mtx);
return mode;
}
static enum nl80211_channel_type
ieee80211_get_superchan(struct ieee80211_local *local,
struct ieee80211_sub_if_data *sdata)
{
enum nl80211_channel_type superchan = NL80211_CHAN_NO_HT;
struct ieee80211_sub_if_data *tmp;
mutex_lock(&local->iflist_mtx);
list_for_each_entry(tmp, &local->interfaces, list) {
if (tmp == sdata)
continue;
if (!ieee80211_sdata_running(tmp))
continue;
switch (tmp->vif.bss_conf.channel_type) {
case NL80211_CHAN_NO_HT:
case NL80211_CHAN_HT20:
if (superchan > tmp->vif.bss_conf.channel_type)
break;
superchan = tmp->vif.bss_conf.channel_type;
break;
case NL80211_CHAN_HT40PLUS:
WARN_ON(superchan == NL80211_CHAN_HT40MINUS);
superchan = NL80211_CHAN_HT40PLUS;
break;
case NL80211_CHAN_HT40MINUS:
WARN_ON(superchan == NL80211_CHAN_HT40PLUS);
superchan = NL80211_CHAN_HT40MINUS;
break;
}
}
mutex_unlock(&local->iflist_mtx);
return superchan;
}
static bool
ieee80211_channel_types_are_compatible(enum nl80211_channel_type chantype1,
enum nl80211_channel_type chantype2,
enum nl80211_channel_type *compat)
{
/*
* start out with chantype1 being the result,
* overwriting later if needed
*/
if (compat)
*compat = chantype1;
switch (chantype1) {
case NL80211_CHAN_NO_HT:
if (compat)
*compat = chantype2;
break;
case NL80211_CHAN_HT20:
/*
* allow any change that doesn't go to no-HT
* (if it already is no-HT no change is needed)
*/
if (chantype2 == NL80211_CHAN_NO_HT)
break;
if (compat)
*compat = chantype2;
break;
case NL80211_CHAN_HT40PLUS:
case NL80211_CHAN_HT40MINUS:
/* allow smaller bandwidth and same */
if (chantype2 == NL80211_CHAN_NO_HT)
break;
if (chantype2 == NL80211_CHAN_HT20)
break;
if (chantype2 == chantype1)
break;
return false;
}
return true;
}
bool ieee80211_set_channel_type(struct ieee80211_local *local,
struct ieee80211_sub_if_data *sdata,
enum nl80211_channel_type chantype)
{
enum nl80211_channel_type superchan;
enum nl80211_channel_type compatchan;
superchan = ieee80211_get_superchan(local, sdata);
if (!ieee80211_channel_types_are_compatible(superchan, chantype,
&compatchan))
return false;
local->_oper_channel_type = compatchan;
if (sdata)
sdata->vif.bss_conf.channel_type = chantype;
return true;
}