cfg80211: Add support for aborting an ongoing scan

Implement new functionality for aborting an ongoing scan.

Add NL80211_CMD_ABORT_SCAN to the nl80211 interface. After
aborting the scan, driver shall provide the scan status by
calling cfg80211_scan_done().

Reviewed-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Vidyullatha Kanchanapally <vkanchan@qti.qualcomm.com>
Signed-off-by: Sunil Dutt <usdutt@qti.qualcomm.com>
[change command to take wdev instead of netdev so that it
 can be used on p2p-device scans]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

5 files changed, 47 insertions, 0 deletions

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index e568872203a5..9bcaaf7cd15a 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -2321,6 +2321,8 @@ struct cfg80211_qos_map {
  *      the driver, and will be valid until passed to cfg80211_scan_done().
  *      For scan results, call cfg80211_inform_bss(); you can call this outside
  *      the scan/scan_done bracket too.
+ * @abort_scan: Tell the driver to abort an ongoing scan. The driver shall
+ *      indicate the status of the scan through cfg80211_scan_done().
  *
  * @auth: Request to authenticate with the specified peer
  *      (invoked with the wireless_dev mutex held)
@@ -2593,6 +2595,7 @@ struct cfg80211_ops {
 
         int     (*scan)(struct wiphy *wiphy,
                         struct cfg80211_scan_request *request);
+        void    (*abort_scan)(struct wiphy *wiphy, struct wireless_dev *wdev);
 
         int     (*auth)(struct wiphy *wiphy, struct net_device *dev,
                         struct cfg80211_auth_request *req);
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index 07099cb14778..5b7b5ebe7ca8 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -820,6 +820,10 @@
  *      as an event to indicate changes for devices with wiphy-specific regdom
  *      management.
  *
+ * @NL80211_CMD_ABORT_SCAN: Stop an ongoing scan. Returns -ENOENT if a scan is
+ *      not running. The driver indicates the status of the scan through
+ *      cfg80211_scan_done().
+ *
  * @NL80211_CMD_MAX: highest used command number
  * @__NL80211_CMD_AFTER_LAST: internal use
  */
@@ -1006,6 +1010,8 @@ enum nl80211_commands {
 
         NL80211_CMD_WIPHY_REG_CHANGE,
 
+        NL80211_CMD_ABORT_SCAN,
+
         /* add new commands above here */
 
         /* used to define NL80211_CMD_MAX below */
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 41e57d0c4d43..67e7b531db79 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -5997,6 +5997,24 @@ static int nl80211_trigger_scan(struct sk_buff *skb, struct genl_info *info)
         return err;
 }
 
+static int nl80211_abort_scan(struct sk_buff *skb, struct genl_info *info)
+{
+        struct cfg80211_registered_device *rdev = info->user_ptr[0];
+        struct wireless_dev *wdev = info->user_ptr[1];
+
+        if (!rdev->ops->abort_scan)
+                return -EOPNOTSUPP;
+
+        if (rdev->scan_msg)
+                return 0;
+
+        if (!rdev->scan_req)
+                return -ENOENT;
+
+        rdev_abort_scan(rdev, wdev);
+        return 0;
+}
+
 static int
 nl80211_parse_sched_scan_plans(struct wiphy *wiphy, int n_plans,
                                struct cfg80211_sched_scan_request *request,
@@ -10945,6 +10963,14 @@ static const struct genl_ops nl80211_ops[] = {
                                   NL80211_FLAG_NEED_RTNL,
         },
         {
+                .cmd = NL80211_CMD_ABORT_SCAN,
+                .doit = nl80211_abort_scan,
+                .policy = nl80211_policy,
+                .flags = GENL_ADMIN_PERM,
+                .internal_flags = NL80211_FLAG_NEED_WDEV_UP |
+                                  NL80211_FLAG_NEED_RTNL,
+        },
+        {
                 .cmd = NL80211_CMD_GET_SCAN,
                 .policy = nl80211_policy,
                 .dumpit = nl80211_dump_scan,
diff --git a/net/wireless/rdev-ops.h b/net/wireless/rdev-ops.h
index b8cc594d409d..8ae0c04f9fc7 100644
--- a/net/wireless/rdev-ops.h
+++ b/net/wireless/rdev-ops.h
@@ -427,6 +427,14 @@ static inline int rdev_scan(struct cfg80211_registered_device *rdev,
         return ret;
 }
 
+static inline void rdev_abort_scan(struct cfg80211_registered_device *rdev,
+                                   struct wireless_dev *wdev)
+{
+        trace_rdev_abort_scan(&rdev->wiphy, wdev);
+        rdev->ops->abort_scan(&rdev->wiphy, wdev);
+        trace_rdev_return_void(&rdev->wiphy);
+}
+
 static inline int rdev_auth(struct cfg80211_registered_device *rdev,
                             struct net_device *dev,
                             struct cfg80211_auth_request *req)
diff --git a/net/wireless/trace.h b/net/wireless/trace.h
index 5b9139e53199..09b242b09bed 100644
--- a/net/wireless/trace.h
+++ b/net/wireless/trace.h
@@ -2917,6 +2917,10 @@ TRACE_EVENT(rdev_set_coalesce,
                   WIPHY_PR_ARG, __entry->n_rules)
 );
 
+DEFINE_EVENT(wiphy_wdev_evt, rdev_abort_scan,
+        TP_PROTO(struct wiphy *wiphy, struct wireless_dev *wdev),
+        TP_ARGS(wiphy, wdev)
+);
 #endif /* !__RDEV_OPS_TRACE || TRACE_HEADER_MULTI_READ */
 
 #undef TRACE_INCLUDE_PATH