From:   Martin Blumenstingl <martin.blumenstingl@googlemail.com>
To:     linux-wireless@vger.kernel.org
Cc:     tony0620emma@gmail.com, kvalo@codeaurora.org,
        johannes@sipsolutions.net, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, Neo Jou <neojou@gmail.com>,
        Jernej Skrabec <jernej.skrabec@gmail.com>,
        Pkshih <pkshih@realtek.com>,
        Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Subject: [PATCH 3/9] rtw88: Move rtw_update_sta_info() out of rtw_ra_mask_info_update_iter()
Date:   Tue, 28 Dec 2021 22:14:55 +0100
Message-Id: <20211228211501.468981-4-martin.blumenstingl@googlemail.com>
In-Reply-To: <20211228211501.468981-1-martin.blumenstingl@googlemail.com>
References: <20211228211501.468981-1-martin.blumenstingl@googlemail.com>
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rtw_update_sta_info() internally access some registers while being
called unter an atomic lock acquired by rtw_iterate_vifs_atomic(). Move
rtw_update_sta_info() call out of (rtw_ra_mask_info_update_iter) in
preparation for SDIO support where register access may sleep.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
---
v1 -> v2:
- this patch is new in v2
- keep rtw_iterate_vifs_atomic() to prevent deadlocks as Johannes
  suggested. Keep track of all relevant stations inside
  rtw_ra_mask_info_update_iter() and the iter-data and then call
  rtw_update_sta_info() while held under rtwdev->mutex instead

 drivers/net/wireless/realtek/rtw88/mac80211.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/realtek/rtw88/mac80211.c b/drivers/net/wireless/realtek/rtw88/mac80211.c
index ae7d97de5fdf..3bd12354a8a1 100644
--- a/drivers/net/wireless/realtek/rtw88/mac80211.c
+++ b/drivers/net/wireless/realtek/rtw88/mac80211.c
@@ -671,6 +671,8 @@ struct rtw_iter_bitrate_mask_data {
 	struct rtw_dev *rtwdev;
 	struct ieee80211_vif *vif;
 	const struct cfg80211_bitrate_mask *mask;
+	unsigned int num_si;
+	struct rtw_sta_info *si[RTW_MAX_MAC_ID_NUM];
 };
 
 static void rtw_ra_mask_info_update_iter(void *data, struct ieee80211_sta *sta)
@@ -691,7 +693,8 @@ static void rtw_ra_mask_info_update_iter(void *data, struct ieee80211_sta *sta)
 	}
 
 	si->use_cfg_mask = true;
-	rtw_update_sta_info(br_data->rtwdev, si);
+
+	br_data->si[br_data->num_si++] = si;
 }
 
 static void rtw_ra_mask_info_update(struct rtw_dev *rtwdev,
@@ -699,11 +702,20 @@ static void rtw_ra_mask_info_update(struct rtw_dev *rtwdev,
 				    const struct cfg80211_bitrate_mask *mask)
 {
 	struct rtw_iter_bitrate_mask_data br_data;
+	unsigned int i;
+
+	mutex_lock(&rtwdev->mutex);
 
 	br_data.rtwdev = rtwdev;
 	br_data.vif = vif;
 	br_data.mask = mask;
+	br_data.num_si = 0;
 	rtw_iterate_stas_atomic(rtwdev, rtw_ra_mask_info_update_iter, &br_data);
+
+	for (i = 0; i < br_data.num_si; i++)
+		rtw_update_sta_info(rtwdev, br_data.si[i]);
+
+	mutex_unlock(&rtwdev->mutex);
 }
 
 static int rtw_ops_set_bitrate_mask(struct ieee80211_hw *hw,
-- 
2.34.1