From 80e78ef74dffb2195e2a1164c18579180a76fd5b Mon Sep 17 00:00:00 2001
From: Dan Williams <dcbw@redhat.com>
Date: Fri, 25 May 2007 22:18:47 -0400
Subject: [PATCH] libertas: fix deadlock SIOCGIWSCAN handler
Update signal quality before the locked scan result translation loop,
because calling libertas_prepare_and_send_command() with the
'waitforrsp' option grabs adapter->lock in the command return processing,
leading to the deadlock.
Signed-off-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
---
drivers/net/wireless/libertas/scan.c | 35 ++++++++++++++++++-----------------
1 file changed, 18 insertions(+), 17 deletions(-)
(limited to 'drivers/net')
diff --git a/drivers/net/wireless/libertas/scan.c b/drivers/net/wireless/libertas/scan.c
index abc9d56..8aaac5f 100644
--- a/drivers/net/wireless/libertas/scan.c
+++ b/drivers/net/wireless/libertas/scan.c
@@ -1506,7 +1506,6 @@ static inline char *libertas_translate_scan(wlan_private *priv,
char *current_val; /* For rates */
struct iw_event iwe; /* Temporary buffer */
int j;
- int ret;
#define PERFECT_RSSI ((u8)50)
#define WORST_RSSI ((u8)0)
#define RSSI_DIFF ((u8)(PERFECT_RSSI - WORST_RSSI))
@@ -1560,22 +1559,18 @@ static inline char *libertas_translate_scan(wlan_private *priv,
iwe.u.qual.noise =
CAL_NF(adapter->NF[TYPE_BEACON][TYPE_NOAVG]);
}
- if ((adapter->mode == IW_MODE_AUTO) &&
- !libertas_SSID_cmp(&adapter->curbssparams.ssid, &bss->ssid)
- && adapter->adhoccreate) {
- ret = libertas_prepare_and_send_command(priv,
- cmd_802_11_rssi,
- 0,
- cmd_option_waitforrsp,
- 0, NULL);
-
- if (!ret) {
- iwe.u.qual.level =
- CAL_RSSI(adapter->SNR[TYPE_RXPD][TYPE_AVG] /
- AVG_SCALE,
- adapter->NF[TYPE_RXPD][TYPE_AVG] /
- AVG_SCALE);
- }
+
+ /* Locally created ad-hoc BSSs won't have beacons if this is the
+ * only station in the adhoc network; so get signal strength
+ * from receive statistics.
+ */
+ if ((adapter->mode == IW_MODE_ADHOC)
+ && adapter->adhoccreate
+ && !libertas_SSID_cmp(&adapter->curbssparams.ssid, &bss->ssid)) {
+ int snr, nf;
+ snr = adapter->SNR[TYPE_RXPD][TYPE_AVG] / AVG_SCALE;
+ nf = adapter->NF[TYPE_RXPD][TYPE_AVG] / AVG_SCALE;
+ iwe.u.qual.level = CAL_RSSI(snr, nf);
}
start = iwe_stream_add_event(start, stop, &iwe, IW_EV_QUAL_LEN);
@@ -1665,6 +1660,12 @@ int libertas_get_scan(struct net_device *dev, struct iw_request_info *info,
if (!adapter->nr_cmd_pending && adapter->last_scanned_channel)
wlan_scan_networks(priv, NULL, 0);
+ /* Update RSSI if current BSS is a locally created ad-hoc BSS */
+ if ((adapter->inframode == wlan802_11ibss) && adapter->adhoccreate) {
+ libertas_prepare_and_send_command(priv, cmd_802_11_rssi, 0,
+ cmd_option_waitforrsp, 0, NULL);
+ }
+
mutex_lock(&adapter->lock);
list_for_each_entry_safe (iter_bss, safe, &adapter->network_list, list) {
char * next_ev;
--
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