cfg80211: send events when devices are added/removed

We're currently sending NEW_WIPHY events for renames (which
is a bit odd, but now can't be changed), but also send them
for really new devices that register.

Also send DEL_WIPHY events when a device is removed, the
event ID for this was already reserved.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

3 files changed, 22 insertions, 7 deletions

diff --git a/net/wireless/core.c b/net/wireless/core.c
index d03d8bdb29ca..a1c40654dd9b 100644
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -130,7 +130,7 @@ int cfg80211_dev_rename(struct cfg80211_registered_device *rdev,
                             newname))
                 pr_err("failed to rename debugfs dir to %s!\n", newname);
 
-        nl80211_notify_dev_rename(rdev);
+        nl80211_notify_wiphy(rdev, NL80211_CMD_NEW_WIPHY);
 
         return 0;
 }
@@ -660,6 +660,8 @@ int wiphy_register(struct wiphy *wiphy)
                 return res;
         }
 
+        nl80211_notify_wiphy(rdev, NL80211_CMD_NEW_WIPHY);
+
         return 0;
 }
 EXPORT_SYMBOL(wiphy_register);
@@ -698,6 +700,7 @@ void wiphy_unregister(struct wiphy *wiphy)
                 rfkill_unregister(rdev->rfkill);
 
         rtnl_lock();
+        nl80211_notify_wiphy(rdev, NL80211_CMD_DEL_WIPHY);
         rdev->wiphy.registered = false;
 
         WARN_ON(!list_empty(&rdev->wdev_list));
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 62bdb1adaa4d..ba4f1723c83a 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -1226,6 +1226,7 @@ struct nl80211_dump_wiphy_state {
 };
 
 static int nl80211_send_wiphy(struct cfg80211_registered_device *rdev,
+                              enum nl80211_commands cmd,
                               struct sk_buff *msg, u32 portid, u32 seq,
                               int flags, struct nl80211_dump_wiphy_state *state)
 {
@@ -1240,7 +1241,7 @@ static int nl80211_send_wiphy(struct cfg80211_registered_device *rdev,
                                 rdev->wiphy.mgmt_stypes;
         u32 features;
 
-        hdr = nl80211hdr_put(msg, portid, seq, flags, NL80211_CMD_NEW_WIPHY);
+        hdr = nl80211hdr_put(msg, portid, seq, flags, cmd);
         if (!hdr)
                 return -ENOBUFS;
 
@@ -1254,6 +1255,9 @@ static int nl80211_send_wiphy(struct cfg80211_registered_device *rdev,
                         cfg80211_rdev_list_generation))
                 goto nla_put_failure;
 
+        if (cmd != NL80211_CMD_NEW_WIPHY)
+                goto finish;
+
         switch (state->split_start) {
         case 0:
                 if (nla_put_u8(msg, NL80211_ATTR_WIPHY_RETRY_SHORT,
@@ -1682,6 +1686,7 @@ static int nl80211_send_wiphy(struct cfg80211_registered_device *rdev,
                 state->split_start = 0;
                 break;
         }
+ finish:
         return genlmsg_end(msg, hdr);
 
  nla_put_failure:
@@ -1756,7 +1761,8 @@ static int nl80211_dump_wiphy(struct sk_buff *skb, struct netlink_callback *cb)
                         continue;
                 /* attempt to fit multiple wiphy data chunks into the skb */
                 do {
-                        ret = nl80211_send_wiphy(rdev, skb,
+                        ret = nl80211_send_wiphy(rdev, NL80211_CMD_NEW_WIPHY,
+                                                 skb,
                                                  NETLINK_CB(cb->skb).portid,
                                                  cb->nlh->nlmsg_seq,
                                                  NLM_F_MULTI, state);
@@ -1811,7 +1817,8 @@ static int nl80211_get_wiphy(struct sk_buff *skb, struct genl_info *info)
         if (!msg)
                 return -ENOMEM;
 
-        if (nl80211_send_wiphy(rdev, msg, info->snd_portid, info->snd_seq, 0,
+        if (nl80211_send_wiphy(rdev, NL80211_CMD_NEW_WIPHY, msg,
+                               info->snd_portid, info->snd_seq, 0,
                                &state) < 0) {
                 nlmsg_free(msg);
                 return -ENOBUFS;
@@ -10101,16 +10108,20 @@ static const struct genl_ops nl80211_ops[] = {
 
 /* notification functions */
 
-void nl80211_notify_dev_rename(struct cfg80211_registered_device *rdev)
+void nl80211_notify_wiphy(struct cfg80211_registered_device *rdev,
+                          enum nl80211_commands cmd)
 {
         struct sk_buff *msg;
         struct nl80211_dump_wiphy_state state = {};
 
+        WARN_ON(cmd != NL80211_CMD_NEW_WIPHY &&
+                cmd != NL80211_CMD_DEL_WIPHY);
+
         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
         if (!msg)
                 return;
 
-        if (nl80211_send_wiphy(rdev, msg, 0, 0, 0, &state) < 0) {
+        if (nl80211_send_wiphy(rdev, cmd, msg, 0, 0, 0, &state) < 0) {
                 nlmsg_free(msg);
                 return;
         }
diff --git a/net/wireless/nl80211.h b/net/wireless/nl80211.h
index 1e6df9630f42..49c9a482dd12 100644
--- a/net/wireless/nl80211.h
+++ b/net/wireless/nl80211.h
@@ -5,7 +5,8 @@
 
 int nl80211_init(void);
 void nl80211_exit(void);
-void nl80211_notify_dev_rename(struct cfg80211_registered_device *rdev);
+void nl80211_notify_wiphy(struct cfg80211_registered_device *rdev,
+                          enum nl80211_commands cmd);
 void nl80211_send_scan_start(struct cfg80211_registered_device *rdev,
                              struct wireless_dev *wdev);
 struct sk_buff *nl80211_build_scan_msg(struct cfg80211_registered_device *rdev,