cfg80211: allow mgmt_frame_register callback to sleep
This callback is currently not allowed to sleep, which makes it more
difficult to implement proper driver methods in mac80211 than it has
to be. Instead of doing asynchronous work here in mac80211, make it
possible for the callback to sleep by doing some asynchronous work
in cfg80211. This also enables improvements to other drivers, like
ath6kl, that would like to sleep in this callback.
While at it, also fix the code to call the driver on the implicit
unregistration when an interface is removed, and do that also when
a P2P-Device wdev is destroyed (otherwise we leak the structs.)
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index a741678..9a529c4 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -2369,8 +2369,7 @@
* method returns 0.)
*
* @mgmt_frame_register: Notify driver that a management frame type was
- * registered. Note that this callback may not sleep, and cannot run
- * concurrently with itself.
+ * registered. The callback is allowed to sleep.
*
* @set_antenna: Set antenna configuration (tx_ant, rx_ant) on the device.
* Parameters are bitmaps of allowed antennas to use for TX/RX. Drivers may
diff --git a/net/wireless/core.c b/net/wireless/core.c
index 2a0bbd2..3893409 100644
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -407,6 +407,9 @@
INIT_LIST_HEAD(&rdev->bss_list);
INIT_WORK(&rdev->scan_done_wk, __cfg80211_scan_done);
INIT_WORK(&rdev->sched_scan_results_wk, __cfg80211_sched_scan_results);
+ INIT_LIST_HEAD(&rdev->mlme_unreg);
+ spin_lock_init(&rdev->mlme_unreg_lock);
+ INIT_WORK(&rdev->mlme_unreg_wk, cfg80211_mlme_unreg_wk);
INIT_DELAYED_WORK(&rdev->dfs_update_channels_wk,
cfg80211_dfs_channels_update_work);
#ifdef CONFIG_CFG80211_WEXT
@@ -802,6 +805,7 @@
cancel_delayed_work_sync(&rdev->dfs_update_channels_wk);
flush_work(&rdev->destroy_work);
flush_work(&rdev->sched_scan_stop_wk);
+ flush_work(&rdev->mlme_unreg_wk);
#ifdef CONFIG_PM
if (rdev->wiphy.wowlan_config && rdev->ops->set_wakeup)
@@ -855,6 +859,7 @@
switch (wdev->iftype) {
case NL80211_IFTYPE_P2P_DEVICE:
+ cfg80211_mlme_purge_registrations(wdev);
cfg80211_stop_p2p_device(rdev, wdev);
break;
default:
diff --git a/net/wireless/core.h b/net/wireless/core.h
index 311eef2..b9d5bc8 100644
--- a/net/wireless/core.h
+++ b/net/wireless/core.h
@@ -59,6 +59,10 @@
struct list_head beacon_registrations;
spinlock_t beacon_registrations_lock;
+ struct list_head mlme_unreg;
+ spinlock_t mlme_unreg_lock;
+ struct work_struct mlme_unreg_wk;
+
/* protected by RTNL only */
int num_running_ifaces;
int num_running_monitor_ifaces;
@@ -348,6 +352,7 @@
int cfg80211_mlme_register_mgmt(struct wireless_dev *wdev, u32 snd_pid,
u16 frame_type, const u8 *match_data,
int match_len);
+void cfg80211_mlme_unreg_wk(struct work_struct *wk);
void cfg80211_mlme_unregister_socket(struct wireless_dev *wdev, u32 nlpid);
void cfg80211_mlme_purge_registrations(struct wireless_dev *wdev);
int cfg80211_mlme_mgmt_tx(struct cfg80211_registered_device *rdev,
diff --git a/net/wireless/mlme.c b/net/wireless/mlme.c
index 7aae329..fb44fa3 100644
--- a/net/wireless/mlme.c
+++ b/net/wireless/mlme.c
@@ -2,6 +2,7 @@
* cfg80211 MLME SAP interface
*
* Copyright (c) 2009, Jouni Malinen <j@w1.fi>
+ * Copyright (c) 2015 Intel Deutschland GmbH
*/
#include <linux/kernel.h>
@@ -389,6 +390,7 @@
struct cfg80211_mgmt_registration {
struct list_head list;
+ struct wireless_dev *wdev;
u32 nlportid;
@@ -399,6 +401,46 @@
u8 match[];
};
+static void
+cfg80211_process_mlme_unregistrations(struct cfg80211_registered_device *rdev)
+{
+ struct cfg80211_mgmt_registration *reg;
+
+ ASSERT_RTNL();
+
+ spin_lock_bh(&rdev->mlme_unreg_lock);
+ while ((reg = list_first_entry_or_null(&rdev->mlme_unreg,
+ struct cfg80211_mgmt_registration,
+ list))) {
+ list_del(®->list);
+ spin_unlock_bh(&rdev->mlme_unreg_lock);
+
+ if (rdev->ops->mgmt_frame_register) {
+ u16 frame_type = le16_to_cpu(reg->frame_type);
+
+ rdev_mgmt_frame_register(rdev, reg->wdev,
+ frame_type, false);
+ }
+
+ kfree(reg);
+
+ spin_lock_bh(&rdev->mlme_unreg_lock);
+ }
+ spin_unlock_bh(&rdev->mlme_unreg_lock);
+}
+
+void cfg80211_mlme_unreg_wk(struct work_struct *wk)
+{
+ struct cfg80211_registered_device *rdev;
+
+ rdev = container_of(wk, struct cfg80211_registered_device,
+ mlme_unreg_wk);
+
+ rtnl_lock();
+ cfg80211_process_mlme_unregistrations(rdev);
+ rtnl_unlock();
+}
+
int cfg80211_mlme_register_mgmt(struct wireless_dev *wdev, u32 snd_portid,
u16 frame_type, const u8 *match_data,
int match_len)
@@ -449,11 +491,18 @@
nreg->match_len = match_len;
nreg->nlportid = snd_portid;
nreg->frame_type = cpu_to_le16(frame_type);
+ nreg->wdev = wdev;
list_add(&nreg->list, &wdev->mgmt_registrations);
+ spin_unlock_bh(&wdev->mgmt_registrations_lock);
+
+ /* process all unregistrations to avoid driver confusion */
+ cfg80211_process_mlme_unregistrations(rdev);
if (rdev->ops->mgmt_frame_register)
rdev_mgmt_frame_register(rdev, wdev, frame_type, true);
+ return 0;
+
out:
spin_unlock_bh(&wdev->mgmt_registrations_lock);
@@ -472,15 +521,12 @@
if (reg->nlportid != nlportid)
continue;
- if (rdev->ops->mgmt_frame_register) {
- u16 frame_type = le16_to_cpu(reg->frame_type);
-
- rdev_mgmt_frame_register(rdev, wdev,
- frame_type, false);
- }
-
list_del(®->list);
- kfree(reg);
+ spin_lock(&rdev->mlme_unreg_lock);
+ list_add_tail(®->list, &rdev->mlme_unreg);
+ spin_unlock(&rdev->mlme_unreg_lock);
+
+ schedule_work(&rdev->mlme_unreg_wk);
}
spin_unlock_bh(&wdev->mgmt_registrations_lock);
@@ -496,16 +542,15 @@
void cfg80211_mlme_purge_registrations(struct wireless_dev *wdev)
{
- struct cfg80211_mgmt_registration *reg, *tmp;
+ struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
spin_lock_bh(&wdev->mgmt_registrations_lock);
-
- list_for_each_entry_safe(reg, tmp, &wdev->mgmt_registrations, list) {
- list_del(®->list);
- kfree(reg);
- }
-
+ spin_lock(&rdev->mlme_unreg_lock);
+ list_splice_tail_init(&wdev->mgmt_registrations, &rdev->mlme_unreg);
+ spin_unlock(&rdev->mlme_unreg_lock);
spin_unlock_bh(&wdev->mgmt_registrations_lock);
+
+ cfg80211_process_mlme_unregistrations(rdev);
}
int cfg80211_mlme_mgmt_tx(struct cfg80211_registered_device *rdev,
diff --git a/net/wireless/rdev-ops.h b/net/wireless/rdev-ops.h
index c6e83a7..c23516d 100644
--- a/net/wireless/rdev-ops.h
+++ b/net/wireless/rdev-ops.h
@@ -733,6 +733,8 @@
rdev_mgmt_frame_register(struct cfg80211_registered_device *rdev,
struct wireless_dev *wdev, u16 frame_type, bool reg)
{
+ might_sleep();
+
trace_rdev_mgmt_frame_register(&rdev->wiphy, wdev , frame_type, reg);
rdev->ops->mgmt_frame_register(&rdev->wiphy, wdev , frame_type, reg);
trace_rdev_return_void(&rdev->wiphy);