From 3ab8227d3e7d1d2bf1829675d3197e3cb600e9f6 Mon Sep 17 00:00:00 2001
From: Sergey Matyukevich <sergey.matyukevich.os@quantenna.com>
Date: Fri, 26 Jul 2019 16:39:32 +0000
Subject: [PATCH] cfg80211: refactor cfg80211_bss_update
Git-commit: 3ab8227d3e7d1d2bf1829675d3197e3cb600e9f6
Patch-mainline: v5.4-rc1
References: jsc#SLE-13430
This patch implements minor refactoring for cfg80211_bss_update function.
Code path for updating known BSS is extracted into dedicated
cfg80211_update_known_bss function.
Signed-off-by: Sergey Matyukevich <sergey.matyukevich.os@quantenna.com>
Link: https://lore.kernel.org/r/20190726163922.27509-2-sergey.matyukevich.os@quantenna.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
net/wireless/scan.c | 171 +++++++++++++++++++++++++++-------------------------
1 file changed, 89 insertions(+), 82 deletions(-)
diff --git a/net/wireless/scan.c b/net/wireless/scan.c
index a98dabab557a..9119f5ce3677 100644
--- a/net/wireless/scan.c
+++ b/net/wireless/scan.c
@@ -1091,6 +1091,93 @@ struct cfg80211_non_tx_bss {
u8 bssid_index;
};
+static bool
+cfg80211_update_known_bss(struct cfg80211_registered_device *rdev,
+ struct cfg80211_internal_bss *known,
+ struct cfg80211_internal_bss *new,
+ bool signal_valid)
+{
+ lockdep_assert_held(&rdev->bss_lock);
+
+ /* Update IEs */
+ if (rcu_access_pointer(new->pub.proberesp_ies)) {
+ const struct cfg80211_bss_ies *old;
+
+ old = rcu_access_pointer(known->pub.proberesp_ies);
+
+ rcu_assign_pointer(known->pub.proberesp_ies,
+ new->pub.proberesp_ies);
+ /* Override possible earlier Beacon frame IEs */
+ rcu_assign_pointer(known->pub.ies,
+ new->pub.proberesp_ies);
+ if (old)
+ kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
+ } else if (rcu_access_pointer(new->pub.beacon_ies)) {
+ const struct cfg80211_bss_ies *old;
+ struct cfg80211_internal_bss *bss;
+
+ if (known->pub.hidden_beacon_bss &&
+ !list_empty(&known->hidden_list)) {
+ const struct cfg80211_bss_ies *f;
+
+ /* The known BSS struct is one of the probe
+ * response members of a group, but we're
+ * receiving a beacon (beacon_ies in the new
+ * bss is used). This can only mean that the
+ * AP changed its beacon from not having an
+ * SSID to showing it, which is confusing so
+ * drop this information.
+ */
+
+ f = rcu_access_pointer(new->pub.beacon_ies);
+ kfree_rcu((struct cfg80211_bss_ies *)f, rcu_head);
+ return false;
+ }
+
+ old = rcu_access_pointer(known->pub.beacon_ies);
+
+ rcu_assign_pointer(known->pub.beacon_ies, new->pub.beacon_ies);
+
+ /* Override IEs if they were from a beacon before */
+ if (old == rcu_access_pointer(known->pub.ies))
+ rcu_assign_pointer(known->pub.ies, new->pub.beacon_ies);
+
+ /* Assign beacon IEs to all sub entries */
+ list_for_each_entry(bss, &known->hidden_list, hidden_list) {
+ const struct cfg80211_bss_ies *ies;
+
+ ies = rcu_access_pointer(bss->pub.beacon_ies);
+ WARN_ON(ies != old);
+
+ rcu_assign_pointer(bss->pub.beacon_ies,
+ new->pub.beacon_ies);
+ }
+
+ if (old)
+ kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head);
+ }
+
+ known->pub.beacon_interval = new->pub.beacon_interval;
+
+ /* don't update the signal if beacon was heard on
+ * adjacent channel.
+ */
+ if (signal_valid)
+ known->pub.signal = new->pub.signal;
+ known->pub.capability = new->pub.capability;
+ known->ts = new->ts;
+ known->ts_boottime = new->ts_boottime;
+ known->parent_tsf = new->parent_tsf;
+ known->pub.chains = new->pub.chains;
+ memcpy(known->pub.chain_signal, new->pub.chain_signal,
+ IEEE80211_MAX_CHAINS);
+ ether_addr_copy(known->parent_bssid, new->parent_bssid);
+ known->pub.max_bssid_indicator = new->pub.max_bssid_indicator;
+ known->pub.bssid_index = new->pub.bssid_index;
+
+ return true;
+}
+
/* Returned bss is reference counted and must be cleaned up appropriately. */
struct cfg80211_internal_bss *
cfg80211_bss_update(struct cfg80211_registered_device *rdev,
@@ -1114,88 +1201,8 @@ cfg80211_bss_update(struct cfg80211_registered_device *rdev,
found = rb_find_bss(rdev, tmp, BSS_CMP_REGULAR);
if (found) {
- /* Update IEs */
- if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
- const struct cfg80211_bss_ies *old;
-
- old = rcu_access_pointer(found->pub.proberesp_ies);
-
- rcu_assign_pointer(found->pub.proberesp_ies,
- tmp->pub.proberesp_ies);
- /* Override possible earlier Beacon frame IEs */
- rcu_assign_pointer(found->pub.ies,
- tmp->pub.proberesp_ies);
- if (old)
- kfree_rcu((struct cfg80211_bss_ies *)old,
- rcu_head);
- } else if (rcu_access_pointer(tmp->pub.beacon_ies)) {
- const struct cfg80211_bss_ies *old;
- struct cfg80211_internal_bss *bss;
-
- if (found->pub.hidden_beacon_bss &&
- !list_empty(&found->hidden_list)) {
- const struct cfg80211_bss_ies *f;
-
- /*
- * The found BSS struct is one of the probe
- * response members of a group, but we're
- * receiving a beacon (beacon_ies in the tmp
- * bss is used). This can only mean that the
- * AP changed its beacon from not having an
- * SSID to showing it, which is confusing so
- * drop this information.
- */
-
- f = rcu_access_pointer(tmp->pub.beacon_ies);
- kfree_rcu((struct cfg80211_bss_ies *)f,
- rcu_head);
- goto drop;
- }
-
- old = rcu_access_pointer(found->pub.beacon_ies);
-
- rcu_assign_pointer(found->pub.beacon_ies,
- tmp->pub.beacon_ies);
-
- /* Override IEs if they were from a beacon before */
- if (old == rcu_access_pointer(found->pub.ies))
- rcu_assign_pointer(found->pub.ies,
- tmp->pub.beacon_ies);
-
- /* Assign beacon IEs to all sub entries */
- list_for_each_entry(bss, &found->hidden_list,
- hidden_list) {
- const struct cfg80211_bss_ies *ies;
-
- ies = rcu_access_pointer(bss->pub.beacon_ies);
- WARN_ON(ies != old);
-
- rcu_assign_pointer(bss->pub.beacon_ies,
- tmp->pub.beacon_ies);
- }
-
- if (old)
- kfree_rcu((struct cfg80211_bss_ies *)old,
- rcu_head);
- }
-
- found->pub.beacon_interval = tmp->pub.beacon_interval;
- /*
- * don't update the signal if beacon was heard on
- * adjacent channel.
- */
- if (signal_valid)
- found->pub.signal = tmp->pub.signal;
- found->pub.capability = tmp->pub.capability;
- found->ts = tmp->ts;
- found->ts_boottime = tmp->ts_boottime;
- found->parent_tsf = tmp->parent_tsf;
- found->pub.chains = tmp->pub.chains;
- memcpy(found->pub.chain_signal, tmp->pub.chain_signal,
- IEEE80211_MAX_CHAINS);
- ether_addr_copy(found->parent_bssid, tmp->parent_bssid);
- found->pub.max_bssid_indicator = tmp->pub.max_bssid_indicator;
- found->pub.bssid_index = tmp->pub.bssid_index;
+ if (!cfg80211_update_known_bss(rdev, found, tmp, signal_valid))
+ goto drop;
} else {
struct cfg80211_internal_bss *new;
struct cfg80211_internal_bss *hidden;
--
2.16.4