On Fri, Dec 18, 2015 at 03:16:52PM +0100, David Coppa wrote:
> On Thu, Dec 17, 2015 at 10:34 PM, Stefan Sperling <s...@stsp.name> wrote:
> > On Thu, Dec 17, 2015 at 08:13:03PM +0100, Stefan Sperling wrote:
> >> This should fix the infinite scanning loops people have been
> >> reporting with 11n-enabled iwn(4), as well as the issue where
> >> clients associating to 11g APs end up in 11b mode and can't
> >> use OFDM data rates.
> >>
> >> ok?
> >
> > Updated diff which allows scanning to work after somebody decided
> > to run 'ifconfig iwn0 media autoselect mode 11n' for some reason.
> > (Don't do that, it won't enforce 11n -- 11n cannot really be set
> > a priori because it's negotiated during association.)
> >
> > Also delete a bit of code from ieee80211_newstate() in ieee80211_proto.c
> > which is pointless now that ieee80211_chan2mode() won't return MODE_11N.
>
> A minor problem I've noticed was dhclient being slower to get the link
> from my AP.
> The patch below fixed it.
Here's yet another update.
I hope this also fixes a transmit problem on 2GHz reported by sthen@.
For some reason ieee80211_end_scan() handled some parts of setting
up 11g ERP but that's now much too early in the association process.
I've moved this code into ieee80211_recv_assoc_resp() because before
then we just don't know whether we're going to end up in 11g or 11n mode.
Index: ieee80211.c
===================================================================
RCS file: /cvs/src/sys/net80211/ieee80211.c,v
retrieving revision 1.53
diff -u -p -r1.53 ieee80211.c
--- ieee80211.c 18 Dec 2015 07:42:24 -0000 1.53
+++ ieee80211.c 18 Dec 2015 14:23:08 -0000
@@ -875,6 +875,14 @@ ieee80211_next_mode(struct ifnet *ifp)
/* Wrap around and ignore turbo mode */
if (ic->ic_curmode == IEEE80211_MODE_TURBO)
continue;
+#ifndef IEEE80211_NO_HT
+ /*
+ * Skip over 11n mode. Its set of channels is the superset
+ * of all channels supported by the other modes.
+ */
+ if (ic->ic_curmode == IEEE80211_MODE_11N)
+ continue;
+#endif
if (ic->ic_curmode >= IEEE80211_MODE_MAX) {
ic->ic_curmode = IEEE80211_MODE_AUTO;
break;
@@ -894,6 +902,11 @@ ieee80211_next_mode(struct ifnet *ifp)
* caller can select a rate set. This is problematic and the
* work here assumes how things work elsewhere in this code.
*
+ * Because the result of this function is ultimately used to select
+ * a rate from the rate set of the returned mode, it must not return
+ * IEEE80211_MODE_11N. This function may be called in 11n mode to find
+ * a non-MCS rate to use for sending frames to non-HT STAs.
+ *
* XXX never returns turbo modes -dcy
*/
enum ieee80211_phymode
@@ -904,19 +917,15 @@ ieee80211_chan2mode(struct ieee80211com
* NB: this assumes the channel would not be supplied to us
* unless it was already compatible with the current mode.
*/
- if (ic->ic_curmode != IEEE80211_MODE_AUTO ||
- chan == IEEE80211_CHAN_ANYC)
+ if (ic->ic_curmode != IEEE80211_MODE_11N &&
+ (ic->ic_curmode != IEEE80211_MODE_AUTO ||
+ chan == IEEE80211_CHAN_ANYC))
return ic->ic_curmode;
/*
- * In autoselect mode; deduce a mode based on the channel
+ * In autoselect or 11n mode; deduce a mode based on the channel
* characteristics. We assume that turbo-only channels
* are not considered when the channel set is constructed.
*/
-#ifndef IEEE80211_NO_HT
- if (IEEE80211_IS_CHAN_N(chan))
- return IEEE80211_MODE_11N;
- else
-#endif
if (IEEE80211_IS_CHAN_T(chan))
return IEEE80211_MODE_TURBO;
else if (IEEE80211_IS_CHAN_5GHZ(chan))
Index: ieee80211_input.c
===================================================================
RCS file: /cvs/src/sys/net80211/ieee80211_input.c,v
retrieving revision 1.145
diff -u -p -r1.145 ieee80211_input.c
--- ieee80211_input.c 12 Dec 2015 13:56:10 -0000 1.145
+++ ieee80211_input.c 18 Dec 2015 13:35:17 -0000
@@ -210,8 +210,7 @@ ieee80211_input_print(struct ieee80211co
"%s: received %s from %s rssi %d mode %s\n", ifp->if_xname,
ieee80211_mgt_subtype_name[subtype >> IEEE80211_FC0_SUBTYPE_SHIFT],
ether_sprintf(wh->i_addr2), rxi->rxi_rssi,
- ieee80211_phymode_name[ieee80211_chan2mode(
- ic, ic->ic_bss->ni_chan)]);
+ ieee80211_phymode_name[ic->ic_curmode]);
task_set(&msg->task, ieee80211_input_print_task, msg);
task_add(systq, &msg->task);
@@ -2250,24 +2249,17 @@ ieee80211_recv_assoc_resp(struct ieee802
ieee80211_ht_negotiate(ic, ni);
/* Hop into 11n mode after associating to an HT AP in a non-11n mode. */
- if (ic->ic_curmode != IEEE80211_MODE_AUTO &&
- ic->ic_curmode != IEEE80211_MODE_11N &&
- (ni->ni_flags & IEEE80211_NODE_HT))
+ if (ni->ni_flags & IEEE80211_NODE_HT)
ieee80211_setmode(ic, IEEE80211_MODE_11N);
-
- /* Hop out of 11n mode after associating to a non-HT AP. */
- if (ic->ic_curmode == IEEE80211_MODE_11N &&
- (ni->ni_flags & IEEE80211_NODE_HT) == 0) {
- if (IEEE80211_IS_CHAN_T(ni->ni_chan))
- ieee80211_setmode(ic, IEEE80211_MODE_TURBO);
- else if (IEEE80211_IS_CHAN_A(ni->ni_chan))
- ieee80211_setmode(ic, IEEE80211_MODE_11A);
- else if (IEEE80211_IS_CHAN_G(ni->ni_chan))
- ieee80211_setmode(ic, IEEE80211_MODE_11G);
- else
- ieee80211_setmode(ic, IEEE80211_MODE_11B);
- }
+ else
#endif
+ ieee80211_setmode(ic, ieee80211_chan2mode(ic, ni->ni_chan));
+ /*
+ * Reset the erp state (mostly the slot time) now that
+ * our operating mode has been nailed down.
+ */
+ ieee80211_reset_erp(ic);
+
/*
* Configure state now that we are associated.
*/
Index: ieee80211_node.c
===================================================================
RCS file: /cvs/src/sys/net80211/ieee80211_node.c,v
retrieving revision 1.93
diff -u -p -r1.93 ieee80211_node.c
--- ieee80211_node.c 12 Dec 2015 11:25:46 -0000 1.93
+++ ieee80211_node.c 18 Dec 2015 13:11:35 -0000
@@ -637,14 +637,6 @@ ieee80211_end_scan(struct ifnet *ifp)
(*ic->ic_node_copy)(ic, ic->ic_bss, selbs);
ni = ic->ic_bss;
- /*
- * Set the erp state (mostly the slot time) to deal with
- * the auto-select case; this should be redundant if the
- * mode is locked.
- */
- ic->ic_curmode = ieee80211_chan2mode(ic, ni->ni_chan);
- ieee80211_reset_erp(ic);
-
if (ic->ic_flags & IEEE80211_F_RSNON)
ieee80211_choose_rsnparams(ic);
else if (ic->ic_flags & IEEE80211_F_WEPON)
Index: ieee80211_proto.c
===================================================================
RCS file: /cvs/src/sys/net80211/ieee80211_proto.c,v
retrieving revision 1.56
diff -u -p -r1.56 ieee80211_proto.c
--- ieee80211_proto.c 24 Nov 2015 13:45:06 -0000 1.56
+++ ieee80211_proto.c 18 Dec 2015 14:38:07 -0000
@@ -894,15 +894,8 @@ justcleanup:
/* initialize bss for probe request */
IEEE80211_ADDR_COPY(ni->ni_macaddr, etherbroadcastaddr);
IEEE80211_ADDR_COPY(ni->ni_bssid, etherbroadcastaddr);
-#ifndef IEEE80211_NO_HT
- if (ic->ic_curmode == IEEE80211_MODE_11N)
- ni->ni_rates = ic->ic_sup_rates[
- IEEE80211_IS_CHAN_2GHZ(ni->ni_chan) ?
- IEEE80211_MODE_11G : IEEE80211_MODE_11A];
- else
-#endif
- ni->ni_rates = ic->ic_sup_rates[
- ieee80211_chan2mode(ic, ni->ni_chan)];
+ ni->ni_rates = ic->ic_sup_rates[
+ ieee80211_chan2mode(ic, ni->ni_chan)];
ni->ni_associd = 0;
ni->ni_rstamp = 0;
switch (ostate) {
