On 4/23/2024 11:56 PM, Karthikeyan Periyasamy wrote:
> Currently, hardware state is not protected across the reconfigure
> operations. However, in single wiphy models, multiple radio/links is
> exposed as a MAC hardware (ieee80211_hw) through the driver hardware
> abstraction (ath12k_hw) layer. In such scenario, we need to protect
> hardware state across the multiple radio/link at the driver hardware
> abstraction (ath12k_hw) layer. Therefore, introduce a new mutex in
> the ath12k_hw layer.
>
> Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.0.1-00029-QCAHKSWPL_SILICONZ-1
>
> Signed-off-by: Karthikeyan Periyasamy <quic_periyasa@xxxxxxxxxxx>
> ---
> drivers/net/wireless/ath/ath12k/core.c | 4 ++++
> drivers/net/wireless/ath/ath12k/core.h | 6 ++++++
> drivers/net/wireless/ath/ath12k/mac.c | 29 ++++++++++++++++++++++++--
> 3 files changed, 37 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/wireless/ath/ath12k/core.c b/drivers/net/wireless/ath/ath12k/core.c
> index a685cfd6fd92..e9aabdb9341c 100644
> --- a/drivers/net/wireless/ath/ath12k/core.c
> +++ b/drivers/net/wireless/ath/ath12k/core.c
> @@ -1048,6 +1048,8 @@ static void ath12k_core_post_reconfigure_recovery(struct ath12k_base *ab)
> if (!ah || ah->state == ATH12K_HW_STATE_OFF)
> continue;
>
> + mutex_lock(&ah->hw_mutex);
> +
> switch (ah->state) {
> case ATH12K_HW_STATE_ON:
> ah->state = ATH12K_HW_STATE_RESTARTING;
> @@ -1078,6 +1080,8 @@ static void ath12k_core_post_reconfigure_recovery(struct ath12k_base *ab)
> "device is wedged, will not restart hw %d\n", i);
> break;
> }
> +
> + mutex_unlock(&ah->hw_mutex);
> }
>
> complete(&ab->driver_recovery);
> diff --git a/drivers/net/wireless/ath/ath12k/core.h b/drivers/net/wireless/ath/ath12k/core.h
> index eff1093fbb6e..3e3e157b6c56 100644
> --- a/drivers/net/wireless/ath/ath12k/core.h
> +++ b/drivers/net/wireless/ath/ath12k/core.h
> @@ -634,11 +634,17 @@ struct ath12k {
> struct ath12k_hw {
> struct ieee80211_hw *hw;
> struct ath12k_base *ab;
> +
> + /* Protect the write operation of the hardware state ath12k_hw::state
> + * between hardware start<=>reconfigure<=>stop transitions.
> + */
> + struct mutex hw_mutex;
> enum ath12k_hw_state state;
> bool regd_updated;
> bool use_6ghz_regd;
> u8 num_radio;
>
> + /* Keep last */
> struct ath12k radio[] __aligned(sizeof(void *));
> };
>
> diff --git a/drivers/net/wireless/ath/ath12k/mac.c b/drivers/net/wireless/ath/ath12k/mac.c
> index 8b003c18796d..3dc95d36b6a2 100644
> --- a/drivers/net/wireless/ath/ath12k/mac.c
> +++ b/drivers/net/wireless/ath/ath12k/mac.c
> @@ -5546,10 +5546,13 @@ static void ath12k_mac_wait_reconfigure(struct ath12k_base *ab)
>
> static int ath12k_mac_start(struct ath12k *ar)
> {
> + struct ath12k_hw *ah = ar->ah;
> struct ath12k_base *ab = ar->ab;
> struct ath12k_pdev *pdev = ar->pdev;
> int ret;
>
> + lockdep_assert_held(&ah->hw_mutex);
> +
> mutex_lock(&ar->conf_mutex);
>
> ret = ath12k_wmi_pdev_set_param(ar, WMI_PDEV_PARAM_PMF_QOS,
> @@ -5664,6 +5667,8 @@ static int ath12k_mac_op_start(struct ieee80211_hw *hw)
>
> ath12k_drain_tx(ah);
>
> + mutex_lock(&ah->hw_mutex);
since this is always unlocked just before we return, it is a good candidate
for the cleanup.h functionality. just change this to:
guard(mutex)(&ah->hw_mutex);
and remove all of the other edits to this function. the mutex will always be
unlocked when the function returns
> +
> switch (ah->state) {
> case ATH12K_HW_STATE_OFF:
> ah->state = ATH12K_HW_STATE_ON;
> @@ -5678,7 +5683,8 @@ static int ath12k_mac_op_start(struct ieee80211_hw *hw)
> ah->state = ATH12K_HW_STATE_OFF;
>
> WARN_ON(1);
> - return -EINVAL;
> + ret = -EINVAL;
> + goto err;
> }
>
> for_each_ar(ah, ar, i) {
> @@ -5692,6 +5698,8 @@ static int ath12k_mac_op_start(struct ieee80211_hw *hw)
> }
> }
>
> + mutex_unlock(&ah->hw_mutex);
> +
> return 0;
>
> fail_start:
> @@ -5700,6 +5708,8 @@ static int ath12k_mac_op_start(struct ieee80211_hw *hw)
> ath12k_mac_stop(ar);
> }
>
> +err:
> + mutex_unlock(&ah->hw_mutex);
> return ret;
> }
>
> @@ -5762,9 +5772,12 @@ int ath12k_mac_rfkill_enable_radio(struct ath12k *ar, bool enable)
>
> static void ath12k_mac_stop(struct ath12k *ar)
> {
> + struct ath12k_hw *ah = ar->ah;
> struct htt_ppdu_stats_info *ppdu_stats, *tmp;
> int ret;
>
> + lockdep_assert_held(&ah->hw_mutex);
> +
> mutex_lock(&ar->conf_mutex);
> ret = ath12k_mac_config_mon_status_default(ar, false);
> if (ret && (ret != -EOPNOTSUPP))
> @@ -5800,10 +5813,14 @@ static void ath12k_mac_op_stop(struct ieee80211_hw *hw)
>
> ath12k_drain_tx(ah);
>
> + mutex_lock(&ah->hw_mutex);
> +
> ah->state = ATH12K_HW_STATE_OFF;
>
> for_each_ar(ah, ar, i)
> ath12k_mac_stop(ar);
> +
> + mutex_unlock(&ah->hw_mutex);
> }
>
> static u8
> @@ -7848,8 +7865,12 @@ ath12k_mac_op_reconfig_complete(struct ieee80211_hw *hw,
> if (reconfig_type != IEEE80211_RECONFIG_TYPE_RESTART)
> return;
>
> - if (ah->state != ATH12K_HW_STATE_RESTARTED)
> + mutex_lock(&ah->hw_mutex);
another good candidate for
guard(mutex)(&ah->hw_mutex);
> +
> + if (ah->state != ATH12K_HW_STATE_RESTARTED) {
> + mutex_unlock(&ah->hw_mutex);
> return;
> + }
>
> ah->state = ATH12K_HW_STATE_ON;
> ieee80211_wake_queues(hw);
> @@ -7904,6 +7925,8 @@ ath12k_mac_op_reconfig_complete(struct ieee80211_hw *hw,
>
> mutex_unlock(&ar->conf_mutex);
> }
> +
> + mutex_unlock(&ah->hw_mutex);
> }
>
> static void
> @@ -8850,6 +8873,8 @@ static struct ath12k_hw *ath12k_mac_hw_allocate(struct ath12k_base *ab,
> ah->ab = ab;
> ah->num_radio = num_pdev_map;
>
> + mutex_init(&ah->hw_mutex);
> +
> for (i = 0; i < num_pdev_map; i++) {
> ab = pdev_map[i].ab;
> pdev_idx = pdev_map[i].pdev_idx;
