summaryrefslogtreecommitdiffstats
path: root/net/mac80211/scan.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2010-05-20 21:04:44 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2010-05-20 21:04:44 -0700
commitf8965467f366fd18f01feafb5db10512d7b4422c (patch)
tree3706a9cd779859271ca61b85c63a1bc3f82d626e /net/mac80211/scan.c
parenta26272e5200765691e67d6780e52b32498fdb659 (diff)
parent2ec8c6bb5d8f3a62a79f463525054bae1e3d4487 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1674 commits) qlcnic: adding co maintainer ixgbe: add support for active DA cables ixgbe: dcb, do not tag tc_prio_control frames ixgbe: fix ixgbe_tx_is_paused logic ixgbe: always enable vlan strip/insert when DCB is enabled ixgbe: remove some redundant code in setting FCoE FIP filter ixgbe: fix wrong offset to fc_frame_header in ixgbe_fcoe_ddp ixgbe: fix header len when unsplit packet overflows to data buffer ipv6: Never schedule DAD timer on dead address ipv6: Use POSTDAD state ipv6: Use state_lock to protect ifa state ipv6: Replace inet6_ifaddr->dead with state cxgb4: notify upper drivers if the device is already up when they load cxgb4: keep interrupts available when the ports are brought down cxgb4: fix initial addition of MAC address cnic: Return SPQ credit to bnx2x after ring setup and shutdown. cnic: Convert cnic_local_flags to atomic ops. can: Fix SJA1000 command register writes on SMP systems bridge: fix build for CONFIG_SYSFS disabled ARCNET: Limit com20020 PCI ID matches for SOHARD cards ... Fix up various conflicts with pcmcia tree drivers/net/ {pcmcia/3c589_cs.c, wireless/orinoco/orinoco_cs.c and wireless/orinoco/spectrum_cs.c} and feature removal (Documentation/feature-removal-schedule.txt). Also fix a non-content conflict due to pm_qos_requirement getting renamed in the PM tree (now pm_qos_request) in net/mac80211/scan.c
Diffstat (limited to 'net/mac80211/scan.c')
-rw-r--r--net/mac80211/scan.c126
1 files changed, 107 insertions, 19 deletions
diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index 85507bd9e34..e1b0be7a57b 100644
--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -14,6 +14,8 @@
#include <linux/if_arp.h>
#include <linux/rtnetlink.h>
+#include <linux/pm_qos_params.h>
+#include <net/sch_generic.h>
#include <linux/slab.h>
#include <net/mac80211.h>
@@ -83,7 +85,7 @@ ieee80211_bss_info_update(struct ieee80211_local *local,
{
struct cfg80211_bss *cbss;
struct ieee80211_bss *bss;
- int clen;
+ int clen, srlen;
s32 signal = 0;
if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
@@ -112,23 +114,24 @@ ieee80211_bss_info_update(struct ieee80211_local *local,
bss->dtim_period = tim_ie->dtim_period;
}
- bss->supp_rates_len = 0;
+ /* replace old supported rates if we get new values */
+ srlen = 0;
if (elems->supp_rates) {
- clen = IEEE80211_MAX_SUPP_RATES - bss->supp_rates_len;
+ clen = IEEE80211_MAX_SUPP_RATES;
if (clen > elems->supp_rates_len)
clen = elems->supp_rates_len;
- memcpy(&bss->supp_rates[bss->supp_rates_len], elems->supp_rates,
- clen);
- bss->supp_rates_len += clen;
+ memcpy(bss->supp_rates, elems->supp_rates, clen);
+ srlen += clen;
}
if (elems->ext_supp_rates) {
- clen = IEEE80211_MAX_SUPP_RATES - bss->supp_rates_len;
+ clen = IEEE80211_MAX_SUPP_RATES - srlen;
if (clen > elems->ext_supp_rates_len)
clen = elems->ext_supp_rates_len;
- memcpy(&bss->supp_rates[bss->supp_rates_len],
- elems->ext_supp_rates, clen);
- bss->supp_rates_len += clen;
+ memcpy(bss->supp_rates + srlen, elems->ext_supp_rates, clen);
+ srlen += clen;
}
+ if (srlen)
+ bss->supp_rates_len = srlen;
bss->wmm_used = elems->wmm_param || elems->wmm_info;
bss->uapsd_supported = is_uapsd_supported(elems);
@@ -246,6 +249,8 @@ void ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
struct ieee80211_local *local = hw_to_local(hw);
bool was_hw_scan;
+ trace_api_scan_completed(local, aborted);
+
mutex_lock(&local->scan_mtx);
/*
@@ -322,6 +327,7 @@ static int ieee80211_start_sw_scan(struct ieee80211_local *local)
ieee80211_offchannel_stop_beaconing(local);
+ local->leave_oper_channel_time = 0;
local->next_scan_state = SCAN_DECISION;
local->scan_channel_idx = 0;
@@ -406,7 +412,7 @@ static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
if (local->ops->hw_scan) {
WARN_ON(!ieee80211_prep_hw_scan(local));
- rc = drv_hw_scan(local, local->hw_scan_req);
+ rc = drv_hw_scan(local, sdata, local->hw_scan_req);
} else
rc = ieee80211_start_sw_scan(local);
@@ -426,11 +432,28 @@ static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
return rc;
}
+static unsigned long
+ieee80211_scan_get_channel_time(struct ieee80211_channel *chan)
+{
+ /*
+ * TODO: channel switching also consumes quite some time,
+ * add that delay as well to get a better estimation
+ */
+ if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN)
+ return IEEE80211_PASSIVE_CHANNEL_TIME;
+ return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME;
+}
+
static int ieee80211_scan_state_decision(struct ieee80211_local *local,
unsigned long *next_delay)
{
bool associated = false;
+ bool tx_empty = true;
+ bool bad_latency;
+ bool listen_int_exceeded;
+ unsigned long min_beacon_int = 0;
struct ieee80211_sub_if_data *sdata;
+ struct ieee80211_channel *next_chan;
/* if no more bands/channels left, complete scan and advance to the idle state */
if (local->scan_channel_idx >= local->scan_req->n_channels) {
@@ -438,7 +461,11 @@ static int ieee80211_scan_state_decision(struct ieee80211_local *local,
return 1;
}
- /* check if at least one STA interface is associated */
+ /*
+ * check if at least one STA interface is associated,
+ * check if at least one STA interface has pending tx frames
+ * and grab the lowest used beacon interval
+ */
mutex_lock(&local->iflist_mtx);
list_for_each_entry(sdata, &local->interfaces, list) {
if (!ieee80211_sdata_running(sdata))
@@ -447,7 +474,16 @@ static int ieee80211_scan_state_decision(struct ieee80211_local *local,
if (sdata->vif.type == NL80211_IFTYPE_STATION) {
if (sdata->u.mgd.associated) {
associated = true;
- break;
+
+ if (sdata->vif.bss_conf.beacon_int <
+ min_beacon_int || min_beacon_int == 0)
+ min_beacon_int =
+ sdata->vif.bss_conf.beacon_int;
+
+ if (!qdisc_all_tx_empty(sdata->dev)) {
+ tx_empty = false;
+ break;
+ }
}
}
}
@@ -456,11 +492,34 @@ static int ieee80211_scan_state_decision(struct ieee80211_local *local,
if (local->scan_channel) {
/*
* we're currently scanning a different channel, let's
- * switch back to the operating channel now if at least
- * one interface is associated. Otherwise just scan the
- * next channel
+ * see if we can scan another channel without interfering
+ * with the current traffic situation.
+ *
+ * Since we don't know if the AP has pending frames for us
+ * we can only check for our tx queues and use the current
+ * pm_qos requirements for rx. Hence, if no tx traffic occurs
+ * at all we will scan as many channels in a row as the pm_qos
+ * latency allows us to. Additionally we also check for the
+ * currently negotiated listen interval to prevent losing
+ * frames unnecessarily.
+ *
+ * Otherwise switch back to the operating channel.
*/
- if (associated)
+ next_chan = local->scan_req->channels[local->scan_channel_idx];
+
+ bad_latency = time_after(jiffies +
+ ieee80211_scan_get_channel_time(next_chan),
+ local->leave_oper_channel_time +
+ usecs_to_jiffies(pm_qos_request(PM_QOS_NETWORK_LATENCY)));
+
+ listen_int_exceeded = time_after(jiffies +
+ ieee80211_scan_get_channel_time(next_chan),
+ local->leave_oper_channel_time +
+ usecs_to_jiffies(min_beacon_int * 1024) *
+ local->hw.conf.listen_interval);
+
+ if (associated && ( !tx_empty || bad_latency ||
+ listen_int_exceeded))
local->next_scan_state = SCAN_ENTER_OPER_CHANNEL;
else
local->next_scan_state = SCAN_SET_CHANNEL;
@@ -492,6 +551,9 @@ static void ieee80211_scan_state_leave_oper_channel(struct ieee80211_local *loca
else
*next_delay = HZ / 10;
+ /* remember when we left the operating channel */
+ local->leave_oper_channel_time = jiffies;
+
/* advance to the next channel to be scanned */
local->next_scan_state = SCAN_SET_CHANNEL;
}
@@ -594,7 +656,7 @@ void ieee80211_scan_work(struct work_struct *work)
}
if (local->hw_scan_req) {
- int rc = drv_hw_scan(local, local->hw_scan_req);
+ int rc = drv_hw_scan(local, sdata, local->hw_scan_req);
mutex_unlock(&local->scan_mtx);
if (rc)
ieee80211_scan_completed(&local->hw, true);
@@ -667,10 +729,12 @@ int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata,
}
int ieee80211_request_internal_scan(struct ieee80211_sub_if_data *sdata,
- const u8 *ssid, u8 ssid_len)
+ const u8 *ssid, u8 ssid_len,
+ struct ieee80211_channel *chan)
{
struct ieee80211_local *local = sdata->local;
int ret = -EBUSY;
+ enum nl80211_band band;
mutex_lock(&local->scan_mtx);
@@ -678,6 +742,30 @@ int ieee80211_request_internal_scan(struct ieee80211_sub_if_data *sdata,
if (local->scan_req)
goto unlock;
+ /* fill internal scan request */
+ if (!chan) {
+ int i, nchan = 0;
+
+ for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
+ if (!local->hw.wiphy->bands[band])
+ continue;
+ for (i = 0;
+ i < local->hw.wiphy->bands[band]->n_channels;
+ i++) {
+ local->int_scan_req->channels[nchan] =
+ &local->hw.wiphy->bands[band]->channels[i];
+ nchan++;
+ }
+ }
+
+ local->int_scan_req->n_channels = nchan;
+ } else {
+ local->int_scan_req->channels[0] = chan;
+ local->int_scan_req->n_channels = 1;
+ }
+
+ local->int_scan_req->ssids = &local->scan_ssid;
+ local->int_scan_req->n_ssids = 1;
memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN);
local->int_scan_req->ssids[0].ssid_len = ssid_len;