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linux/include/net/regulatory.h
Luis R. Rodriguez b2e253cf30 cfg80211: Fix regulatory bug with multiple cards and delays
When two cards are connected with the same regulatory domain
if CRDA had a delayed response then cfg80211's own set regulatory
domain would still be the world regulatory domain. There was a bug
on cfg80211's logic such that it assumed that once you pegged a
request as the last request it was already the currently set
regulatory domain. This would mean we would race setting a stale
regulatory domain to secondary cards which had the same regulatory
domain since the alpha2 would match.

We fix this by processing each regulatory request atomically,
and only move on to the next one once we get it fully processed.
In the case CRDA is not present we will simply world roam.

This issue is only present when you have a slow system and the
CRDA processing is delayed. Because of this it is not a known
regression.

Without this fix when a delay is present with CRDA the second card
would end up with an intersected regulatory domain and not allow it
to use the channels it really is designed for. When two cards with
two different regulatory domains were inserted you'd end up
rejecting the second card's regulatory domain request.
This fails with mac80211_hswim's regtest=2 (two requests, same alpha2)
and regtest=3 (two requests, different alpha2) module parameter
options.

This was reproduced and tested against mac80211_hwsim using this
CRDA delayer:

       #!/bin/bash
       echo $COUNTRY >> /tmp/log
       sleep 2
       /sbin/crda.orig

And these regulatory tests:

       modprobe mac80211_hwsim regtest=2
       modprobe mac80211_hwsim regtest=3

Reported-by: Mark Mentovai <mark@moxienet.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Tested-by: Mark Mentovai <mark@moxienet.com>
Tested-by: Bruno Randolf <br1@einfach.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-11-22 15:48:51 -05:00

109 lines
3.5 KiB
C

#ifndef __NET_REGULATORY_H
#define __NET_REGULATORY_H
/*
* regulatory support structures
*
* Copyright 2008-2009 Luis R. Rodriguez <lrodriguez@atheros.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
/**
* enum environment_cap - Environment parsed from country IE
* @ENVIRON_ANY: indicates country IE applies to both indoor and
* outdoor operation.
* @ENVIRON_INDOOR: indicates country IE applies only to indoor operation
* @ENVIRON_OUTDOOR: indicates country IE applies only to outdoor operation
*/
enum environment_cap {
ENVIRON_ANY,
ENVIRON_INDOOR,
ENVIRON_OUTDOOR,
};
/**
* struct regulatory_request - used to keep track of regulatory requests
*
* @wiphy_idx: this is set if this request's initiator is
* %REGDOM_SET_BY_COUNTRY_IE or %REGDOM_SET_BY_DRIVER. This
* can be used by the wireless core to deal with conflicts
* and potentially inform users of which devices specifically
* cased the conflicts.
* @initiator: indicates who sent this request, could be any of
* of those set in nl80211_reg_initiator (%NL80211_REGDOM_SET_BY_*)
* @alpha2: the ISO / IEC 3166 alpha2 country code of the requested
* regulatory domain. We have a few special codes:
* 00 - World regulatory domain
* 99 - built by driver but a specific alpha2 cannot be determined
* 98 - result of an intersection between two regulatory domains
* 97 - regulatory domain has not yet been configured
* @intersect: indicates whether the wireless core should intersect
* the requested regulatory domain with the presently set regulatory
* domain.
* @processed: indicates whether or not this requests has already been
* processed. When the last request is processed it means that the
* currently regulatory domain set on cfg80211 is updated from
* CRDA and can be used by other regulatory requests. When a
* the last request is not yet processed we must yield until it
* is processed before processing any new requests.
* @country_ie_checksum: checksum of the last processed and accepted
* country IE
* @country_ie_env: lets us know if the AP is telling us we are outdoor,
* indoor, or if it doesn't matter
* @list: used to insert into the reg_requests_list linked list
*/
struct regulatory_request {
int wiphy_idx;
enum nl80211_reg_initiator initiator;
char alpha2[2];
bool intersect;
bool processed;
enum environment_cap country_ie_env;
struct list_head list;
};
struct ieee80211_freq_range {
u32 start_freq_khz;
u32 end_freq_khz;
u32 max_bandwidth_khz;
};
struct ieee80211_power_rule {
u32 max_antenna_gain;
u32 max_eirp;
};
struct ieee80211_reg_rule {
struct ieee80211_freq_range freq_range;
struct ieee80211_power_rule power_rule;
u32 flags;
};
struct ieee80211_regdomain {
u32 n_reg_rules;
char alpha2[2];
struct ieee80211_reg_rule reg_rules[];
};
#define MHZ_TO_KHZ(freq) ((freq) * 1000)
#define KHZ_TO_MHZ(freq) ((freq) / 1000)
#define DBI_TO_MBI(gain) ((gain) * 100)
#define MBI_TO_DBI(gain) ((gain) / 100)
#define DBM_TO_MBM(gain) ((gain) * 100)
#define MBM_TO_DBM(gain) ((gain) / 100)
#define REG_RULE(start, end, bw, gain, eirp, reg_flags) \
{ \
.freq_range.start_freq_khz = MHZ_TO_KHZ(start), \
.freq_range.end_freq_khz = MHZ_TO_KHZ(end), \
.freq_range.max_bandwidth_khz = MHZ_TO_KHZ(bw), \
.power_rule.max_antenna_gain = DBI_TO_MBI(gain),\
.power_rule.max_eirp = DBM_TO_MBM(eirp), \
.flags = reg_flags, \
}
#endif