1. 10 Jul, 2009 2 commits
    • Helmut Schaa's avatar
      mac80211: shorten the passive dwell time for sw scans · 96f7e739
      Helmut Schaa authored
      
      
      mac80211's software scan implementation uses a passive dwell time of
      (HZ / 5) which means we stay 200ms on each passive channel. Compared
      to iwlwifi's hw scan and the old ipw* drivers which use values around
      120ms this is quite long.
      
      Reducing the passive dwell time from 200ms to 125ms should save us
      something around a second on cards capable of 11a and we should still be
      able to catch beacons from most access points (assuming a ~100ms beacon
      interval).
      Signed-off-by: default avatarHelmut Schaa <helmut.schaa@googlemail.com>
      Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
      96f7e739
    • Johannes Berg's avatar
      mac80211: push rx status into skb->cb · f1d58c25
      Johannes Berg authored
      
      
      Within mac80211, we often need to copy the rx status into
      skb->cb. This is wasteful, as drivers could be building it
      in there to start with. This patch changes the API so that
      drivers are expected to pass the RX status in skb->cb, now
      accessible as IEEE80211_SKB_RXCB(skb). It also updates all
      drivers to pass the rx status in there, but only by making
      them memcpy() it into place before the call to the receive
      function (ieee80211_rx(_irqsafe)). Each driver can now be
      optimised on its own schedule.
      Signed-off-by: default avatarJohannes Berg <johannes@sipsolutions.net>
      Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
      f1d58c25
  2. 20 May, 2009 1 commit
    • Johannes Berg's avatar
      mac80211: cancel/restart all timers across suspend/resume · 5bb644a0
      Johannes Berg authored
      
      
      We forgot to cancel all timers in mac80211 when suspending.
      In particular we forgot to deal with some things that can
      cause hardware reconfiguration -- while it is down.
      
      While at it we go ahead and add a warning in ieee80211_sta_work()
      if its run while the suspend->resume cycle is in effect. This
      should not happen and if it does it would indicate there is
      a bug lurking in either mac80211 or mac80211 drivers.
      
      With this now wpa_supplicant doesn't blink when I go to suspend
      and resume where as before there where issues with some timers
      running during the suspend->resume cycle. This caused a lot of
      incorrect assumptions and would at times bring back the device
      in an incoherent, but mostly recoverable, state.
      Signed-off-by: default avatarLuis R. Rodriguez <lrodriguez@atheros.com>
      Signed-off-by: default avatarJohannes Berg <johannes@sipsolutions.net>
      Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
      5bb644a0
  3. 11 May, 2009 2 commits
    • Johannes Berg's avatar
      mac80211: improve scan timing · 99c84cb0
      Johannes Berg authored
      
      
      The call to ieee80211_hw_config() is supposed to apply changes
      synchronously, so once it returns the parameters are applied to
      the hardware. Thus, there really is no need to delay the probing
      by the channel switch time again since the channel switch has
      already happened once we get to this code.
      
      Additionally, there is no need to wait for a NAV update (probe
      delay) when the channel is passively scanned. Remove that extra
      time too.
      
      This cuts scanning time from over 7 seconds to under 4 on ar9170,
      which is due to the number of channels scanned and ar9170's switch
      time being advertised as 135ms (my test now indicates it is about
      77ms with the current driver, but the difference might also be due
      to using a different machine with different USB controllers).
      Signed-off-by: default avatarJohannes Berg <johannes@sipsolutions.net>
      Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
      99c84cb0
    • Johannes Berg's avatar
      mac80211: fix scan channel race · 58905ca5
      Johannes Berg authored
      
      
      When a software scan starts, it first sets sw_scanning, but
      leaves the scan_channel "unset" (it currently actually gets
      initialised to a default). Now, when something else tries
      to (re)configure the hardware in the window between these two
      events (after sw_scanning = true, but before scan_channel is
      set), the current code switches to the (unset!) scan_channel.
      This causes trouble, especially when switching bands and
      sending frames on the wrong channel.
      
      To work around this, leave scan_channel initialised to NULL
      and use it to determine whether or not a switch to a different
      channel should occur (and also use the same condition to check
      whether to adjust power for scan or not).
      
      Additionally, avoid reconfiguring the hardware completely when
      recalculating idle resulted in no changes, this was the problem
      that originally led us to discover the race condition in the
      first place, which was helpfully bisected by Pavel. This part
      of the patch should not be necessary with the other fixes, but
      not calling the ieee80211_hw_config function when we know it to
      be unnecessary is certainly a correct thing to do.
      
      Unfortunately, this patch cannot and does not fix the race
      condition completely, but due to the way the scan code is
      structured it makes the particular problem Pavel discovered
      (race while changing channel at the same time as transmitting
      frames) go away. To fix it completely, more work especially
      with locking configuration is needed.
      Bisected-by: default avatarPavel Roskin <proski@gnu.org>
      Signed-off-by: default avatarJohannes Berg <johannes@sipsolutions.net>
      Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
      58905ca5
  4. 06 May, 2009 4 commits
    • Johannes Berg's avatar
      mac80211: tell driver when idle · 5cff20e6
      Johannes Berg authored
      
      
      When we aren't doing anything in mac80211, we can turn off
      much of the hardware, depending on the driver/hw. Not doing
      anything, aka being idle, means:
      
       * no monitor interfaces
       * no AP/mesh/wds interfaces
       * any station interfaces are in DISABLED state
       * any IBSS interfaces aren't trying to be in a network
       * we aren't trying to scan
      
      By creating a new function that verifies these conditions and calling
      it at strategic points where the states of those conditions change,
      we can easily make mac80211 tell the driver when we are idle to save
      power.
      
      Additionally, this fixes a small quirk where a recalculated powersave
      state is passed to the driver even if the hardware is about to stopped
      completely.
      
      This patch intentionally doesn't touch radio_enabled because that is
      currently implemented to be a soft rfkill which is inappropriate here
      when we need to be able to wake up with low latency.
      
      One thing I'm not entirely sure about is this:
      
        phy0: device no longer idle - in use
        wlan0: direct probe to AP 00:11:24:91:07:4d try 1
        wlan0 direct probe responded
        wlan0: authenticate with AP 00:11:24:91:07:4d
        wlan0: authenticated
      > phy0: device now idle
      > phy0: device no longer idle - in use
        wlan0: associate with AP 00:11:24:91:07:4d
        wlan0: RX AssocResp from 00:11:24:91:07:4d (capab=0x401 status=0 aid=1)
        wlan0: associated
      
      Is it appropriate to go into idle state for a short time when we have
      just authenticated, but not associated yet? This happens only with the
      userspace SME, because we cannot really know how long it will wait
      before asking us to associate. Would going idle after a short timeout
      be more appropriate? We may need to revisit this, depending on what
      happens.
      Signed-off-by: default avatarJohannes Berg <johannes@sipsolutions.net>
      Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
      5cff20e6
    • Johannes Berg's avatar
      mac80211: add driver ops wrappers · 24487981
      Johannes Berg authored
      
      
      In order to later add tracing or verifications to the driver
      calls mac80211 makes, this patch adds static inline wrappers
      for all operations.
      
      All calls are now written as
      
      	drv_<op>(local, ...);
      
      instead of
      
      	local->ops-><op>(&local->hw, ...);
      
      Where necessary, the wrappers also do existence checking and
      return default values as appropriate.
      Signed-off-by: default avatarJohannes Berg <johannes@sipsolutions.net>
      Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
      24487981
    • Johannes Berg's avatar
      mac80211: unify config_interface and bss_info_changed · 2d0ddec5
      Johannes Berg authored
      
      
      The config_interface method is a little strange, it contains the
      BSSID and beacon updates, while bss_info_changed contains most
      other BSS information for each interface. This patch removes
      config_interface and rolls all the information it previously
      passed to drivers into bss_info_changed.
      Signed-off-by: default avatarJohannes Berg <johannes@sipsolutions.net>
      Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
      2d0ddec5
    • Johannes Berg's avatar
      mac80211: fix scan races and rework scanning · f3b85252
      Johannes Berg authored
      
      
      There are some places marked
      	/* XXX maybe racy? */
      and they really are racy because there's no locking.
      
      This patch reworks much of the scan code, and introduces proper
      locking for the scan request as well as the internal scanning
      (which is necessary for IBSS/managed modes). Helper functions
      are added to call the scanning code whenever necessary. The
      scan deferring is changed to simply queue the scanning work
      instead of trying to start the scan in place, the scanning work
      will then take care of the rest.
      
      Also, currently when internal scans are requested for an interface
      that is trying to associate, we reject such scans. This was not
      intended, the mlme code has provisions to scan twice when it can't
      find the BSS to associate with right away; this has never worked
      properly. Fix this by not rejecting internal scan requests for an
      interface that is associating.
      Signed-off-by: default avatarJohannes Berg <johannes@sipsolutions.net>
      Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
      f3b85252
  5. 22 Apr, 2009 3 commits
  6. 27 Mar, 2009 2 commits
  7. 16 Mar, 2009 1 commit
    • Helmut Schaa's avatar
      mac80211: handle failed scan requests in STA mode · af88b907
      Helmut Schaa authored
      
      
      If cfg80211 requests a scan it awaits either a return code != 0 from
      the scan function or the cfg80211_scan_done to be called. In case of
      a STA mac80211's scan function ever returns 0 and queues the scan request.
      If ieee80211_sta_work is executed and ieee80211_start_scan fails for
      some reason cfg80211_scan_done will never be called but cfg80211 still
      thinks the scan was triggered successfully and will refuse any future
      scan requests due to drv->scan_req not being cleaned up.
      
      If a scan is triggered from within the MLME a similar problem appears. If
      ieee80211_start_scan returns an error, local->scan_req will not be reset
      and mac80211 will refuse any future scan requests.
      
      Hence, in both cases call ieee80211_scan_failed (which notifies cfg80211
      and resets local->scan_req) if ieee80211_start_scan returns an error.
      Signed-off-by: default avatarHelmut Schaa <helmut.schaa@googlemail.com>
      Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
      af88b907
  8. 27 Feb, 2009 4 commits
  9. 13 Feb, 2009 4 commits
  10. 11 Feb, 2009 1 commit
  11. 29 Jan, 2009 3 commits
  12. 10 Nov, 2008 1 commit
  13. 31 Oct, 2008 2 commits
  14. 14 Oct, 2008 1 commit
  15. 15 Sep, 2008 5 commits
  16. 11 Sep, 2008 4 commits