summaryrefslogtreecommitdiff
path: root/include
diff options
context:
space:
mode:
authorJohannes Berg <johannes@sipsolutions.net>2010-05-05 15:25:02 +0200
committerJohn W. Linville <linville@tuxdriver.com>2010-05-07 14:55:50 -0400
commitf444de05d20e27cdd960c13fcbcfca3099f03143 (patch)
treea7fbef60420d88dda5840e06094be21ee3eb1dc0 /include
parentac8dd506e40ee2c7fcc61654a44c32555a0a8d6c (diff)
cfg80211/mac80211: better channel handling
Currently (all tested with hwsim) you can do stupid things like setting up an AP on a certain channel, then adding another virtual interface and making that associate on another channel -- this will make the beaconing to move channel but obviously without the necessary IEs data update. In order to improve this situation, first make the configuration APIs (cfg80211 and nl80211) aware of multi-channel operation -- we'll eventually need that in the future anyway. There's one userland API change and one API addition. The API change is that now SET_WIPHY must be called with virtual interface index rather than only wiphy index in order to take effect for that interface -- luckily all current users (hostapd) do that. For monitor interfaces, the old setting is preserved, but monitors are always slaved to other devices anyway so no guarantees. The second userland API change is the introduction of a per virtual interface SET_CHANNEL command, that hostapd should use going forward to make it easier to understand what's going on (it can automatically detect a kernel with this command). Other than mac80211, no existing cfg80211 drivers are affected by this change because they only allow a single virtual interface. mac80211, however, now needs to be aware that the channel settings are per interface now, and needs to disallow (for now) real multi-channel operation, which is another important part of this patch. One of the immediate benefits is that you can now start hostapd to operate on a hardware that already has a connection on another virtual interface, as long as you specify the same channel. Note that two things are left unhandled (this is an improvement -- not a complete fix): * different HT/no-HT modes currently you could start an HT AP and then connect to a non-HT network on the same channel which would configure the hardware for no HT; that can be fixed fairly easily * CSA An AP we're connected to on a virtual interface might indicate switching channels, and in that case we would follow it, regardless of how many other interfaces are operating; this requires more effort to fix but is pretty rare after all Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com>
Diffstat (limited to 'include')
-rw-r--r--include/linux/nl80211.h13
-rw-r--r--include/net/cfg80211.h11
2 files changed, 22 insertions, 2 deletions
diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h
index f8750f9a65b8..b7c77f9712f4 100644
--- a/include/linux/nl80211.h
+++ b/include/linux/nl80211.h
@@ -52,6 +52,8 @@
* %NL80211_ATTR_WIPHY_CHANNEL_TYPE, %NL80211_ATTR_WIPHY_RETRY_SHORT,
* %NL80211_ATTR_WIPHY_RETRY_LONG, %NL80211_ATTR_WIPHY_FRAG_THRESHOLD,
* and/or %NL80211_ATTR_WIPHY_RTS_THRESHOLD.
+ * However, for setting the channel, see %NL80211_CMD_SET_CHANNEL
+ * instead, the support here is for backward compatibility only.
* @NL80211_CMD_NEW_WIPHY: Newly created wiphy, response to get request
* or rename notification. Has attributes %NL80211_ATTR_WIPHY and
* %NL80211_ATTR_WIPHY_NAME.
@@ -329,6 +331,15 @@
* @NL80211_CMD_NOTIFY_CQM: Connection quality monitor notification. This
* command is used as an event to indicate the that a trigger level was
* reached.
+ * @NL80211_CMD_SET_CHANNEL: Set the channel (using %NL80211_ATTR_WIPHY_FREQ
+ * and %NL80211_ATTR_WIPHY_CHANNEL_TYPE) the given interface (identifed
+ * by %NL80211_ATTR_IFINDEX) shall operate on.
+ * In case multiple channels are supported by the device, the mechanism
+ * with which it switches channels is implementation-defined.
+ * When a monitor interface is given, it can only switch channel while
+ * no other interfaces are operating to avoid disturbing the operation
+ * of any other interfaces, and other interfaces will again take
+ * precedence when they are used.
*
* @NL80211_CMD_MAX: highest used command number
* @__NL80211_CMD_AFTER_LAST: internal use
@@ -428,6 +439,8 @@ enum nl80211_commands {
NL80211_CMD_SET_CQM,
NL80211_CMD_NOTIFY_CQM,
+ NL80211_CMD_SET_CHANNEL,
+
/* add new commands above here */
/* used to define NL80211_CMD_MAX below */
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 7d10c0182f53..b44a2e5321a3 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -966,7 +966,11 @@ struct cfg80211_pmksa {
*
* @set_txq_params: Set TX queue parameters
*
- * @set_channel: Set channel
+ * @set_channel: Set channel for a given wireless interface. Some devices
+ * may support multi-channel operation (by channel hopping) so cfg80211
+ * doesn't verify much. Note, however, that the passed netdev may be
+ * %NULL as well if the user requested changing the channel for the
+ * device itself, or for a monitor interface.
*
* @scan: Request to do a scan. If returning zero, the scan request is given
* the driver, and will be valid until passed to cfg80211_scan_done().
@@ -1095,7 +1099,7 @@ struct cfg80211_ops {
int (*set_txq_params)(struct wiphy *wiphy,
struct ieee80211_txq_params *params);
- int (*set_channel)(struct wiphy *wiphy,
+ int (*set_channel)(struct wiphy *wiphy, struct net_device *dev,
struct ieee80211_channel *chan,
enum nl80211_channel_type channel_type);
@@ -1461,6 +1465,8 @@ struct cfg80211_cached_keys;
* @list: (private) Used to collect the interfaces
* @netdev: (private) Used to reference back to the netdev
* @current_bss: (private) Used by the internal configuration code
+ * @channel: (private) Used by the internal configuration code to track
+ * user-set AP, monitor and WDS channels for wireless extensions
* @bssid: (private) Used by the internal configuration code
* @ssid: (private) Used by the internal configuration code
* @ssid_len: (private) Used by the internal configuration code
@@ -1507,6 +1513,7 @@ struct wireless_dev {
struct cfg80211_internal_bss *authtry_bsses[MAX_AUTH_BSSES];
struct cfg80211_internal_bss *auth_bsses[MAX_AUTH_BSSES];
struct cfg80211_internal_bss *current_bss; /* associated / joined */
+ struct ieee80211_channel *channel;
bool ps;
int ps_timeout;