aboutsummaryrefslogtreecommitdiff
path: root/net/mac80211
AgeCommit message (Collapse)Author
2014-02-06mac80211: Fix IBSS disconnectSujith Manoharan
Currently, when a station leaves an IBSS network, the corresponding BSS is not dropped from cfg80211 if there are other active stations in the network. But, the small window that is present when trying to determine a station's status based on IEEE80211_IBSS_MERGE_INTERVAL introduces a race. Instead of trying to keep the BSS, always remove it when leaving an IBSS network. There is not much benefit to retain the BSS entry since it will be added with a subsequent join operation. This fixes an issue where a dangling BSS entry causes ath9k to wait for a beacon indefinitely. Cc: <stable@vger.kernel.org> Reported-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-02-06mac80211: release the channel in error path in start_apEmmanuel Grumbach
When the driver cannot start the AP or when the assignement of the beacon goes wrong, we need to unassign the vif. Cc: stable@vger.kernel.org Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-02-06mac80211: avoid deadlock revealed by lockdepEmmanuel Grumbach
sdata->u.ap.request_smps_work can’t be flushed synchronously under wdev_lock(wdev) since ieee80211_request_smps_ap_work itself locks the same lock. While at it, reset the driver_smps_mode when the ap is stopped to its default: OFF. This solves: ====================================================== [ INFO: possible circular locking dependency detected ] 3.12.0-ipeer+ #2 Tainted: G O ------------------------------------------------------- rmmod/2867 is trying to acquire lock: ((&sdata->u.ap.request_smps_work)){+.+...}, at: [<c105b8d0>] flush_work+0x0/0x90 but task is already holding lock: (&wdev->mtx){+.+.+.}, at: [<f9b32626>] cfg80211_stop_ap+0x26/0x230 [cfg80211] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&wdev->mtx){+.+.+.}: [<c10aefa9>] lock_acquire+0x79/0xe0 [<c1607a1a>] mutex_lock_nested+0x4a/0x360 [<fb06288b>] ieee80211_request_smps_ap_work+0x2b/0x50 [mac80211] [<c105cdd8>] process_one_work+0x198/0x450 [<c105d469>] worker_thread+0xf9/0x320 [<c10669ff>] kthread+0x9f/0xb0 [<c1613397>] ret_from_kernel_thread+0x1b/0x28 -> #0 ((&sdata->u.ap.request_smps_work)){+.+...}: [<c10ae9df>] __lock_acquire+0x183f/0x1910 [<c10aefa9>] lock_acquire+0x79/0xe0 [<c105b917>] flush_work+0x47/0x90 [<c105d867>] __cancel_work_timer+0x67/0xe0 [<c105d90f>] cancel_work_sync+0xf/0x20 [<fb0765cc>] ieee80211_stop_ap+0x8c/0x340 [mac80211] [<f9b3268c>] cfg80211_stop_ap+0x8c/0x230 [cfg80211] [<f9b0d8f9>] cfg80211_leave+0x79/0x100 [cfg80211] [<f9b0da72>] cfg80211_netdev_notifier_call+0xf2/0x4f0 [cfg80211] [<c160f2c9>] notifier_call_chain+0x59/0x130 [<c106c6de>] __raw_notifier_call_chain+0x1e/0x30 [<c106c70f>] raw_notifier_call_chain+0x1f/0x30 [<c14f8213>] call_netdevice_notifiers_info+0x33/0x70 [<c14f8263>] call_netdevice_notifiers+0x13/0x20 [<c14f82a4>] __dev_close_many+0x34/0xb0 [<c14f83fe>] dev_close_many+0x6e/0xc0 [<c14f9c77>] rollback_registered_many+0xa7/0x1f0 [<c14f9dd4>] unregister_netdevice_many+0x14/0x60 [<fb06f4d9>] ieee80211_remove_interfaces+0xe9/0x170 [mac80211] [<fb055116>] ieee80211_unregister_hw+0x56/0x110 [mac80211] [<fa3e9396>] iwl_op_mode_mvm_stop+0x26/0xe0 [iwlmvm] [<f9b9d8ca>] _iwl_op_mode_stop+0x3a/0x70 [iwlwifi] [<f9b9d96f>] iwl_opmode_deregister+0x6f/0x90 [iwlwifi] [<fa405179>] __exit_compat+0xd/0x19 [iwlmvm] [<c10b8bf9>] SyS_delete_module+0x179/0x2b0 [<c1613421>] sysenter_do_call+0x12/0x32 Fixes: 687da132234f ("mac80211: implement SMPS for AP") Cc: <stable@vger.kernel.org> [3.13] Reported-by: Ilan Peer <ilan.peer@intel.com> Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-02-06mac80211: move roc cookie assignment earlierEliad Peller
ieee80211_start_roc_work() might add a new roc to existing roc, and tell cfg80211 it has already started. However, this might happen before the roc cookie was set, resulting in REMAIN_ON_CHANNEL (started) event with null cookie. Consequently, it can make wpa_supplicant go out of sync. Fix it by setting the roc cookie earlier. Cc: stable@vger.kernel.org Signed-off-by: Eliad Peller <eliad@wizery.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-01-17Merge branch 'master' of ↵John W. Linville
git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next into for-davem
2014-01-14Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
2014-01-10net: core: explicitly select a txq before doing l2 forwardingJason Wang
Currently, the tx queue were selected implicitly in ndo_dfwd_start_xmit(). The will cause several issues: - NETIF_F_LLTX were removed for macvlan, so txq lock were done for macvlan instead of lower device which misses the necessary txq synchronization for lower device such as txq stopping or frozen required by dev watchdog or control path. - dev_hard_start_xmit() was called with NULL txq which bypasses the net device watchdog. - dev_hard_start_xmit() does not check txq everywhere which will lead a crash when tso is disabled for lower device. Fix this by explicitly introducing a new param for .ndo_select_queue() for just selecting queues in the case of l2 forwarding offload. netdev_pick_tx() was also extended to accept this parameter and dev_queue_xmit_accel() was used to do l2 forwarding transmission. With this fixes, NETIF_F_LLTX could be preserved for macvlan and there's no need to check txq against NULL in dev_hard_start_xmit(). Also there's no need to keep a dedicated ndo_dfwd_start_xmit() and we can just reuse the code of dev_queue_xmit() to do the transmission. In the future, it was also required for macvtap l2 forwarding support since it provides a necessary synchronization method. Cc: John Fastabend <john.r.fastabend@intel.com> Cc: Neil Horman <nhorman@tuxdriver.com> Cc: e1000-devel@lists.sourceforge.net Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-10Merge branch 'master' of ↵John W. Linville
git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next into for-davem Conflicts: net/ieee802154/6lowpan.c
2014-01-10mac80211: handle MMPDUs at EOSP correctlyJohannes Berg
If a uAPSD service period ends with an MMPDU, we currently just send that MMPDU, but it obviously won't get the EOSP bit set as it doesn't have a QoS header. This contradicts the standard, so add a QoS-nulldata frame after the MMPDU to properly terminate the service period with a frame that has EOSP set. Also fix a bug wrt. the TID for the MMPDU, it shouldn't be set to 0 unconditionally but use the actual TID that was assigned. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-01-10mac80211: reset TX info flags when frame will be reprocessedJohannes Berg
The temporary TX info flags need to be cleared if the frame will be processed through the TX handlers again, otherwise it can get messed up. This fixes a bug that happened when an aggregation session was stopped while the station was sleeping - some frames might get transmitted marked as aggregation erroneously without this fix. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-01-10mac80211: release multiple ACs in uAPSD, fix more-data bugJohannes Berg
When a response for PS-Poll or a uAPSD trigger frame is sent, the more-data bit should be set according to 802.11-2012 11.2.1.5 h), meaning that it should indicate more data on the relevant ACs (delivery-enabled or nondelivery-enabled for uAPSD or PS-Poll.) In, for example, the following scenario: * 1 frame on VO queue (either in driver or in mac80211) * at least 1 frame on VI queue (in the driver) * both VO/VI are delivery-enabled * uAPSD trigger frame received The more-data flag to the driver would not be set, even though it should be. While fixing this, I noticed that we should really release frames from multiple ACs where there's data buffered in the driver for the corresponding TIDs. To address all this, restructure the code a bit to consider all ACs if we only release driver frames or only buffered frames. This also addresses the more-data bug described above as now the TIDs will all be marked as released, so the driver will have to check the number of frames. While at it, clarify some code and comments and remove the found variable, replacing it with the appropriate sw/hw release check. Reported-by: Eliad Peller <eliad@wizery.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-01-10mac80211: fix PS-Poll driver release TIDJohannes Berg
Using ffs() for the PS-Poll release TID is wrong, it will cause frames to be released in order 0 1 2 3 4 5 6 7 instead of the correct 7 6 5 4 3 0 2 1. Fix this by adding a new function that implements "highest priority TID" properly. Reported-by: Eliad Peller <eliad@wizery.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-01-07mac80211: allow to set smps mode to OFF in AP modeEmmanuel Grumbach
In managed mode, we should not ask for OFF mode because the power settings may still require DYNAMIC. In AP mode, this should be allowed since the default settings is OFF and AUTOMATIC is not allowed. Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-01-07mac80211: clean up prepare_for_handlers() return valueJohannes Berg
Using an int with 0/1 is not very common, make the function return a bool instead with the same values (false/true). Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-01-07mac80211: simplify code in ieee80211_prepare_and_rx_handleEmmanuel Grumbach
No need to assign the return value of prepare_for_handlers to a variable if the only usage is to test it. Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-01-07mac80211: clean up garbage in commentEmmanuel Grumbach
Not clear how this landed here. Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-01-06mac80211: sync dtim_count to TSFThomas Pedersen
On starting a mesh or AP BSS, the interface dtim_count countdown should match that of the driver TSF. Signed-off-by: Thomas Pedersen <twpedersen@gmail.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-01-06mac80211: enable WME for peer mesh STAChun-Yeow Yeoh
Enable the WME for peer mesh STA so that the driver, such as wcn36xx, will pick this up and enabling it in HW. Signed-off-by: Chun-Yeow Yeoh <yeohchunyeow@gmail.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-01-06mac80211: fix memory leak in register_hw() error pathJohannes Berg
Move the internal scan request allocation below the last sanity check in ieee80211_register_hw() to avoid leaking memory if the sanity check actually triggers. Reported-by: ZHAO Gang <gamerh2o@gmail.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-01-06mac80211: handle station TX latency allocation errorsJohannes Berg
When the station's TX latency data structures need to be allocated, handle failures properly and also free all the structures if there are any other problems. Move the allocation code up so that allocation failures don't trigger rate control algorithm calls. Reported-by: ZHAO Gang <gamerh2o@gmail.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-01-06mac80211: clean up netdev debugfs macros a bitJohannes Berg
Clean up the file macros a bit and use that to remove the unnecessary format function for the tkip MIC test file that really is write-only. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-01-06mac80211: add tracing for ieee80211_sta_set_bufferedJohannes Berg
This is useful for debugging issues with drivers using this function (erroneously), so add tracing for the API call. Change-Id: Ice9d7eabb8fecbac188f0a741920d3488de700ec Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-01-01Merge branch 'master' of ↵John W. Linville
git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next into for-davem
2013-12-30cfg80211/mac80211: correct qos-map lockingJohannes Berg
Since the RTNL can't always be held, use wdev/sdata locking for the qos-map dereference in mac80211. This requires cfg80211 to consistently lock it, which it was missing in one place. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-12-26mac8011: slight optimization of addr comparedingtianhong
Use the possibly more efficient ether_addr_equal to instead of memcmp. Cc: Johannes Berg <johannes@sipsolutions.net> Cc: John W. Linville <linville@tuxdriver.com> Cc: David Miller <davem@davemloft.net> Cc: linux-wireless@vger.kernel.org Cc: netdev@vger.kernel.org Signed-off-by: Wang Weidong <wangweidong1@huawei.com> Signed-off-by: Ding Tianhong <dingtianhong@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-19mac80211: Add support for QoS mappingKyeyoon Park
Implement set_qos_map() handler for mac80211 to enable QoS mapping functionality. Signed-off-by: Kyeyoon Park <kyeyoonp@qca.qualcomm.com> Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-12-19cfg80211: Add support for QoS mappingKyeyoon Park
This allows QoS mapping from external networks to be implemented as defined in IEEE Std 802.11-2012, 10.24.9. APs can use this to advertise DSCP ranges and exceptions for mapping frames to a specific UP over Wi-Fi. The payload of the QoS Map Set element (IEEE Std 802.11-2012, 8.4.2.97) is sent to the driver through the new NL80211_ATTR_QOS_MAP attribute to configure the local behavior either on the AP (based on local configuration) or on a station (based on information received from the AP). Signed-off-by: Kyeyoon Park <kyeyoonp@qca.qualcomm.com> Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-12-19mac80211: add helper functions for tracking P2P NoA stateFelix Fietkau
Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-12-19mac80211: fix iflist_mtx/mtx locking in radar detectionJohannes Berg
The scan code creates an iflist_mtx -> mtx locking dependency, and a few other places, notably radar detection, were creating the opposite dependency, causing lockdep to complain. As scan and radar detection are mutually exclusive, the deadlock can't really happen in practice, but it's still bad form. A similar issue exists in the monitor mode code, but this is only used by channel-context drivers right now and those have to have hardware scan, so that also can't happen. Still, fix these issues by making some of the channel context code require the mtx to be held rather than acquiring it, thus allowing the monitor/radar callers to keep the iflist_mtx->mtx lock ordering. While at it, also fix access to the local->scanning variable in the radar code, and document that radar_detect_enabled is now properly protected by the mtx. All this would now introduce an ABBA deadlock between the DFS work cancelling and local->mtx, so change the locking there a bit to not need to use cancel_delayed_work_sync() but be able to just use cancel_delayed_work(). The work is also safely stopped/removed when the interface is stopped, so no extra changes are needed. Reported-by: Kalle Valo <kvalo@qca.qualcomm.com> Tested-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-12-19mac80211: remove unnecessary iflist_mtx lockingJohannes Berg
The radar detection code changed a few times, and due to the changes some iflist_mtx locking stayed in that isn't actually necessary - remove it. One version of the code needed it because an AP interface's VLAN list was changed to use this, but then we moved the list handling outside of the chanctx handling and thus the locking was no longer needed. Tested-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-12-19mac80211: align struct ps_data.tim to unsigned longJoe Perches
Its address is used as an unsigned long *, so make sure that the tim u8 array is properly aligned. Signed-off-by: Joe Perches <joe@perches.com Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-12-18mac80211: make ieee80211_recalc_radar_chanctx staticJohannes Berg
The function is only used in one file, so move it up a bit to avoid forward declarations and make it static. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-12-18mac80211: fix checkpatch errorsWeilong Chen
Fix a number of different checkpatch errors. Signed-off-by: Weilong Chen <chenweilong@huawei.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-12-16mac80211: move "bufferable MMPDU" check to fix AP mode scanFelix Fietkau
The check needs to apply to both multicast and unicast packets, otherwise probe requests on AP mode scans are sent through the multicast buffer queue, which adds long delays (often longer than the scanning interval). Cc: stable@vger.kernel.org Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-12-16mac80211: read station mgmt keys via get_key callMax Stepanov
Allow to read management keys stored in a station's gtk key array with a get_key function. Signed-off-by: Max Stepanov <Max.Stepanov@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-12-16mac80211: check pairwise key_idx on get_key callMax Stepanov
Verify that a pairwise key index value on ieee80211_get_key call doesn't exceed the boundaries of the pairwise key array. Signed-off-by: Max Stepanov <Max.Stepanov@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-12-16mac80211: align ieee80211_ibss_csa_beacon() with ieee80211_assign_beacon()Luciano Coelho
The return value of ieee80211_ibss_csa_beacon is not aligned with the return value of ieee80211_assign_beacon(). For consistency and to be able to use both functions with similar code, change ieee80211_ibss_csa_beacon() not to send the bss changed notification itself, but return what has changed so the caller can send the notification instead. Tested by: Simon Wunderlich <sw@simonwunderlich.de> Acked by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Luciano Coelho <luciano.coelho@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-12-16mac80211: refactor ieee80211_ibss_process_chanswitch()Luciano Coelho
Refactor ieee80211_ibss_process_chanswitch() to use ieee80211_channel_switch() and avoid code duplication. Tested by: Simon Wunderlich <sw@simonwunderlich.de> Acked by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Luciano Coelho <luciano.coelho@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-12-16mac80211: update adjusting TBTT bit in beaconThomas Pedersen
This regression was introduced in "mac80211: cache mesh beacon". mesh_sync_offset_adjust_tbtt() was assuming that the beacon would be rebuilt in every single pre-tbtt interrupt, but now the beacon update happens on the workqueue, and it must be ready for immediate delivery to the driver. Save a pointer to the meshconf IE in the beacon_data (this works because both the IE pointer and beacon buffer are protected by the same rcu_{dereference,assign_pointer}()) for quick updates during pre-tbtt. This is faster and a little prettier than iterating over the elements to find the meshconf IE every time. Signed-off-by: Thomas Pedersen <thomas@cozybit.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-12-16mac80211: reschedule sched scan after HW restartDavid Spinadel
Keep the sched scan req when starting sched scan, and reschedule it in case of HW restart during sched scan. The upper layer don't have to know about the restart. Signed-off-by: David Spinadel <david.spinadel@intel.com> Reviewed-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-12-16mac80211: make ieee80211_assign_beacon() staticLuciano Coelho
This function is not used anywhere else than in cfg.c, so there's no need to export it. Signed-off-by: Luciano Coelho <luciano.coelho@intel.com> Reviewed-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-12-16mac80211: lock sdata in ieee80211_csa_connection_drop_work()Luciano Coelho
We call ieee80211_ibss_disconnect(), which requires sdata to be locked, so lock the sdata during ieee80211_csa_connection_drop_work(). Cc: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Luciano Coelho <luciano.coelho@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-12-16mac80211: let the driver reserve extra tailroom in beaconsFelix Fietkau
Can be used to add extra IEs (such as P2P NoA) without having to reallocate the buffer. Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-12-16mac80211: free all AP/VLAN keys at onceJohannes Berg
When the AP interface is stopped, free all AP and VLAN keys at once to only require synchronize_net() once. Since that does synchronize_net(), also move two such calls into the function (using the new force_synchronize parameter) to avoid doing it twice. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-12-16mac80211: optimise mixed AP/VLAN station removalJohannes Berg
Teach sta_info_flush() to optionally also remove stations from all VLANs associated with an AP interface to optimise the station removal (in particular, synchronize_net().) To not have to add the vlans argument throughout, do some refactoring. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-12-16mac80211: optimise synchronize_net() for sta_info_flushJohannes Berg
There's no reason to have one synchronize_net() for each removed station, refactor the code slightly to have just a single synchronize_net() for all stations. Note that this is currently useless as hostapd removes stations one by one and this coalescing never happens. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-12-16mac80211: move synchronize_net() before sta key removalJohannes Berg
There's no reason to do this inside the sta key removal since the keys can only be reached through the sta (and not by the driver at all) so once the sta can no longer be reached, the keys are safe. This will allow further optimisation opportunities with multiple stations. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-12-16mac80211: don't delay station destructionJohannes Berg
If we can assume that stations are never referenced by the driver after sta_state returns (and this is true since the previous iwlmvm patch and for all other drivers) then we don't need to delay station destruction, and don't need to play tricks with rcu_barrier() etc. This should speed up some scenarios like hostapd shutdown. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-12-16mac80211: move 4-addr sta pointer clearing before synchronize_rcu()Johannes Berg
The pointer should be cleared before synchronize_rcu() so that the consequently dead station won't be found by any lookups in the TX or RX paths. Also check that the station is actually the one being removed, the check is not needed because each 4-addr VLAN can only have a single station and non-4-addr VLANs always have a NULL pointer there, but the code is clearer this way (and we avoid the memory write.) Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-12-16mac80211: add pre-RCU-sync sta removal driver operationJohannes Berg
Currently, mac80211 allows drivers to keep RCU-protected station references that are cleared when the station is removed from the driver and consequently needs to synchronize twice, once before removing the station from the driver (so it can guarantee that the station is no longer used in TX towards the driver) and once after the station is removed from the driver. Add a new pre-RCU-synchronisation station removal operation to the API to allow drivers to clear/invalidate their RCU-protected station pointers before the RCU synchronisation. This will allow removing the second synchronisation by changing the driver API so that the driver may no longer assume a valid RCU-protected pointer after sta_remove/sta_state returns. The alternative to this would be to synchronize_rcu() in all the drivers that currently rely on this behaviour (only iwlmvm) but that would defeat the purpose. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-17 12:28:37 +0000