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freebsd-nq/sys/net80211/ieee80211_tdma.c
Adrian Chadd 23401900d3 Fix a panic in the wifi stack when a software beacon miss occurs in the wrong state. 
The ieee80211_swbmiss() callout is not called with the ic lock held, so it's
quite possible the scheduler will run the callout during a state change.

This patch:

* changes the swbmiss callout to be locked by the ic lock
* enforces the ic lock being held across the beacon vap functions
  by grabbing it inside beacon_miss() and beacon_swmiss().

This ensures that the ic lock is held (and thus the VAP state
stays constant) during beacon miss and software miss processing.
Since the callout is removed whilst the ic lock is held, it also
ensures that the ic lock can't be called during a state change
or exhibit any race conditions seen above.

Both Edgar and Joel report that this patch fixes the crash and
doesn't introduce new issues.

Reported by:	Edgar Martinez <emartinez@kbcnetworks.com>
Reported by:	Joel Dahl <joel@vnode.se>
Reported by:	emaste
2011-10-02 02:42:31 +00:00

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/*-
* Copyright (c) 2007-2009 Sam Leffler, Errno Consulting
* Copyright (c) 2007-2009 Intel Corporation
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
#ifdef __FreeBSD__
__FBSDID("$FreeBSD$");
#endif
/*
* IEEE 802.11 TDMA mode support.
*/
#include "opt_inet.h"
#include "opt_tdma.h"
#include "opt_wlan.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/malloc.h>
#include <sys/kernel.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/endian.h>
#include <sys/errno.h>
#include <sys/proc.h>
#include <sys/sysctl.h>
#include <net/if.h>
#include <net/if_media.h>
#include <net/if_llc.h>
#include <net/ethernet.h>
#include <net/bpf.h>
#include <net80211/ieee80211_var.h>
#include <net80211/ieee80211_tdma.h>
#include <net80211/ieee80211_input.h>
#ifndef TDMA_SLOTLEN_DEFAULT
#define TDMA_SLOTLEN_DEFAULT 10*1000 /* 10ms */
#endif
#ifndef TDMA_SLOTCNT_DEFAULT
#define TDMA_SLOTCNT_DEFAULT 2 /* 2x (pt-to-pt) */
#endif
#ifndef TDMA_BINTVAL_DEFAULT
#define TDMA_BINTVAL_DEFAULT 5 /* 5x ~= 100TU beacon intvl */
#endif
#ifndef TDMA_TXRATE_11B_DEFAULT
#define TDMA_TXRATE_11B_DEFAULT 2*11
#endif
#ifndef TDMA_TXRATE_11G_DEFAULT
#define TDMA_TXRATE_11G_DEFAULT 2*24
#endif
#ifndef TDMA_TXRATE_11A_DEFAULT
#define TDMA_TXRATE_11A_DEFAULT 2*24
#endif
#ifndef TDMA_TXRATE_TURBO_DEFAULT
#define TDMA_TXRATE_TURBO_DEFAULT 2*24
#endif
#ifndef TDMA_TXRATE_HALF_DEFAULT
#define TDMA_TXRATE_HALF_DEFAULT 2*12
#endif
#ifndef TDMA_TXRATE_QUARTER_DEFAULT
#define TDMA_TXRATE_QUARTER_DEFAULT 2*6
#endif
#ifndef TDMA_TXRATE_11NA_DEFAULT
#define TDMA_TXRATE_11NA_DEFAULT (4 | IEEE80211_RATE_MCS)
#endif
#ifndef TDMA_TXRATE_11NG_DEFAULT
#define TDMA_TXRATE_11NG_DEFAULT (4 | IEEE80211_RATE_MCS)
#endif
#define TDMA_VERSION_VALID(_version) \
(TDMA_VERSION_V2 <= (_version) && (_version) <= TDMA_VERSION)
#define TDMA_SLOTCNT_VALID(_slotcnt) \
(2 <= (_slotcnt) && (_slotcnt) <= TDMA_MAXSLOTS)
/* XXX magic constants */
#define TDMA_SLOTLEN_VALID(_slotlen) \
(2*100 <= (_slotlen) && (unsigned)(_slotlen) <= 0xfffff)
/* XXX probably should set a max */
#define TDMA_BINTVAL_VALID(_bintval) (1 <= (_bintval))
/*
* This code is not prepared to handle more than 2 slots.
*/
CTASSERT(TDMA_MAXSLOTS == 2);
static void tdma_vdetach(struct ieee80211vap *vap);
static int tdma_newstate(struct ieee80211vap *, enum ieee80211_state, int);
static void tdma_beacon_miss(struct ieee80211vap *vap);
static void tdma_recv_mgmt(struct ieee80211_node *, struct mbuf *,
int subtype, int rssi, int nf);
static int tdma_update(struct ieee80211vap *vap,
const struct ieee80211_tdma_param *tdma, struct ieee80211_node *ni,
int pickslot);
static int tdma_process_params(struct ieee80211_node *ni,
const u_int8_t *ie, int rssi, int nf, const struct ieee80211_frame *wh);
static void
settxparms(struct ieee80211vap *vap, enum ieee80211_phymode mode, int rate)
{
vap->iv_txparms[mode].ucastrate = rate;
vap->iv_txparms[mode].mcastrate = rate;
}
static void
setackpolicy(struct ieee80211com *ic, int noack)
{
struct ieee80211_wme_state *wme = &ic->ic_wme;
int ac;
for (ac = 0; ac < WME_NUM_AC; ac++) {
wme->wme_chanParams.cap_wmeParams[ac].wmep_noackPolicy = noack;
wme->wme_wmeChanParams.cap_wmeParams[ac].wmep_noackPolicy = noack;
}
}
void
ieee80211_tdma_vattach(struct ieee80211vap *vap)
{
struct ieee80211_tdma_state *ts;
KASSERT(vap->iv_caps & IEEE80211_C_TDMA,
("not a tdma vap, caps 0x%x", vap->iv_caps));
ts = (struct ieee80211_tdma_state *) malloc(
sizeof(struct ieee80211_tdma_state), M_80211_VAP, M_NOWAIT | M_ZERO);
if (ts == NULL) {
printf("%s: cannot allocate TDMA state block\n", __func__);
/* NB: fall back to adhdemo mode */
vap->iv_caps &= ~IEEE80211_C_TDMA;
return;
}
/* NB: default configuration is passive so no beacons */
ts->tdma_version = TDMA_VERSION;
ts->tdma_slotlen = TDMA_SLOTLEN_DEFAULT;
ts->tdma_slotcnt = TDMA_SLOTCNT_DEFAULT;
ts->tdma_bintval = TDMA_BINTVAL_DEFAULT;
ts->tdma_slot = 1; /* passive operation */
/* setup default fixed rates */
settxparms(vap, IEEE80211_MODE_11A, TDMA_TXRATE_11A_DEFAULT);
settxparms(vap, IEEE80211_MODE_11B, TDMA_TXRATE_11B_DEFAULT);
settxparms(vap, IEEE80211_MODE_11G, TDMA_TXRATE_11G_DEFAULT);
settxparms(vap, IEEE80211_MODE_TURBO_A, TDMA_TXRATE_TURBO_DEFAULT);
settxparms(vap, IEEE80211_MODE_TURBO_G, TDMA_TXRATE_TURBO_DEFAULT);
settxparms(vap, IEEE80211_MODE_STURBO_A, TDMA_TXRATE_TURBO_DEFAULT);
settxparms(vap, IEEE80211_MODE_11NA, TDMA_TXRATE_11NA_DEFAULT);
settxparms(vap, IEEE80211_MODE_11NG, TDMA_TXRATE_11NG_DEFAULT);
settxparms(vap, IEEE80211_MODE_HALF, TDMA_TXRATE_HALF_DEFAULT);
settxparms(vap, IEEE80211_MODE_QUARTER, TDMA_TXRATE_QUARTER_DEFAULT);
setackpolicy(vap->iv_ic, 1); /* disable ACK's */
ts->tdma_opdetach = vap->iv_opdetach;
vap->iv_opdetach = tdma_vdetach;
ts->tdma_newstate = vap->iv_newstate;
vap->iv_newstate = tdma_newstate;
vap->iv_bmiss = tdma_beacon_miss;
ts->tdma_recv_mgmt = vap->iv_recv_mgmt;
vap->iv_recv_mgmt = tdma_recv_mgmt;
vap->iv_tdma = ts;
}
static void
tdma_vdetach(struct ieee80211vap *vap)
{
struct ieee80211_tdma_state *ts = vap->iv_tdma;
if (ts == NULL) {
/* NB: should not have touched any ic state */
return;
}
ts->tdma_opdetach(vap);
free(vap->iv_tdma, M_80211_VAP);
vap->iv_tdma = NULL;
setackpolicy(vap->iv_ic, 0); /* enable ACK's */
}
static void
sta_leave(void *arg, struct ieee80211_node *ni)
{
struct ieee80211vap *vap = arg;
if (ni->ni_vap == vap && ni != vap->iv_bss)
ieee80211_node_leave(ni);
}
/*
* TDMA state machine handler.
*/
static int
tdma_newstate(struct ieee80211vap *vap, enum ieee80211_state nstate, int arg)
{
struct ieee80211_tdma_state *ts = vap->iv_tdma;
struct ieee80211com *ic = vap->iv_ic;
enum ieee80211_state ostate;
int status;
IEEE80211_LOCK_ASSERT(ic);
ostate = vap->iv_state;
IEEE80211_DPRINTF(vap, IEEE80211_MSG_STATE, "%s: %s -> %s (%d)\n",
__func__, ieee80211_state_name[ostate],
ieee80211_state_name[nstate], arg);
if (vap->iv_flags_ext & IEEE80211_FEXT_SWBMISS)
callout_stop(&vap->iv_swbmiss);
if (nstate == IEEE80211_S_SCAN &&
(ostate == IEEE80211_S_INIT || ostate == IEEE80211_S_RUN) &&
ts->tdma_slot != 0) {
/*
* Override adhoc behaviour when operating as a slave;
* we need to scan even if the channel is locked.
*/
vap->iv_state = nstate; /* state transition */
ieee80211_cancel_scan(vap); /* background scan */
if (ostate == IEEE80211_S_RUN) {
/* purge station table; entries are stale */
ieee80211_iterate_nodes(&ic->ic_sta, sta_leave, vap);
}
if (vap->iv_flags_ext & IEEE80211_FEXT_SCANREQ) {
ieee80211_check_scan(vap,
vap->iv_scanreq_flags,
vap->iv_scanreq_duration,
vap->iv_scanreq_mindwell,
vap->iv_scanreq_maxdwell,
vap->iv_scanreq_nssid, vap->iv_scanreq_ssid);
vap->iv_flags_ext &= ~IEEE80211_FEXT_SCANREQ;
} else
ieee80211_check_scan_current(vap);
status = 0;
} else {
status = ts->tdma_newstate(vap, nstate, arg);
}
if (status == 0 &&
nstate == IEEE80211_S_RUN && ostate != IEEE80211_S_RUN &&
(vap->iv_flags_ext & IEEE80211_FEXT_SWBMISS) &&
ts->tdma_slot != 0 &&
vap->iv_des_chan == IEEE80211_CHAN_ANYC) {
/*
* Start s/w beacon miss timer for slave devices w/o
* hardware support. Note we do this only if we're
* not locked to a channel (i.e. roam to follow the
* master). The 2x is a fudge for our doing this in
* software.
*/
vap->iv_swbmiss_period = IEEE80211_TU_TO_TICKS(
2 * vap->iv_bmissthreshold * ts->tdma_bintval *
((ts->tdma_slotcnt * ts->tdma_slotlen) / 1024));
vap->iv_swbmiss_count = 0;
callout_reset(&vap->iv_swbmiss, vap->iv_swbmiss_period,
ieee80211_swbmiss, vap);
}
return status;
}
static void
tdma_beacon_miss(struct ieee80211vap *vap)
{
struct ieee80211_tdma_state *ts = vap->iv_tdma;
struct ieee80211com *ic = vap->iv_ic;
IEEE80211_LOCK_ASSERT(ic);
KASSERT((vap->iv_ic->ic_flags & IEEE80211_F_SCAN) == 0, ("scanning"));
KASSERT(vap->iv_state == IEEE80211_S_RUN,
("wrong state %d", vap->iv_state));
IEEE80211_DPRINTF(vap,
IEEE80211_MSG_STATE | IEEE80211_MSG_TDMA | IEEE80211_MSG_DEBUG,
"beacon miss, mode %u state %s\n",
vap->iv_opmode, ieee80211_state_name[vap->iv_state]);
callout_stop(&vap->iv_swbmiss);
if (ts->tdma_peer != NULL) { /* XXX? can this be null? */
ieee80211_notify_node_leave(vap->iv_bss);
ts->tdma_peer = NULL;
/*
* Treat beacon miss like an associate failure wrt the
* scan policy; this forces the entry in the scan cache
* to be ignored after several tries.
*/
ieee80211_scan_assoc_fail(vap, vap->iv_bss->ni_macaddr,
IEEE80211_STATUS_TIMEOUT);
}
#if 0
ts->tdma_inuse = 0; /* clear slot usage */
#endif
ieee80211_new_state(vap, IEEE80211_S_SCAN, 0);
}
static void
tdma_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m0,
int subtype, int rssi, int nf)
{
struct ieee80211com *ic = ni->ni_ic;
struct ieee80211vap *vap = ni->ni_vap;
struct ieee80211_tdma_state *ts = vap->iv_tdma;
if (subtype == IEEE80211_FC0_SUBTYPE_BEACON &&
(ic->ic_flags & IEEE80211_F_SCAN) == 0) {
struct ieee80211_frame *wh = mtod(m0, struct ieee80211_frame *);
struct ieee80211_scanparams scan;
if (ieee80211_parse_beacon(ni, m0, &scan) != 0)
return;
if (scan.tdma == NULL) {
/*
* TDMA stations must beacon a TDMA ie; ignore
* any other station.
* XXX detect overlapping bss and change channel
*/
IEEE80211_DISCARD(vap,
IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
wh, ieee80211_mgt_subtype_name[subtype >>
IEEE80211_FC0_SUBTYPE_SHIFT],
"%s", "no TDMA ie");
vap->iv_stats.is_rx_mgtdiscard++;
return;
}
if (ni == vap->iv_bss &&
!IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
/*
* Fake up a node for this newly
* discovered member of the IBSS.
*/
ni = ieee80211_add_neighbor(vap, wh, &scan);
if (ni == NULL) {
/* NB: stat kept for alloc failure */
return;
}
}
/*
* Check for state updates.
*/
if (IEEE80211_ADDR_EQ(wh->i_addr3, ni->ni_bssid)) {
/*
* Count frame now that we know it's to be processed.
*/
vap->iv_stats.is_rx_beacon++;
IEEE80211_NODE_STAT(ni, rx_beacons);
/*
* Record tsf of last beacon. NB: this must be
* done before calling tdma_process_params
* as deeper routines reference it.
*/
memcpy(&ni->ni_tstamp.data, scan.tstamp,
sizeof(ni->ni_tstamp.data));
/*
* Count beacon frame for s/w bmiss handling.
*/
vap->iv_swbmiss_count++;
/*
* Process tdma ie. The contents are used to sync
* the slot timing, reconfigure the bss, etc.
*/
(void) tdma_process_params(ni, scan.tdma, rssi, nf, wh);
return;
}
/*
* NB: defer remaining work to the adhoc code; this causes
* 2x parsing of the frame but should happen infrequently
*/
}
ts->tdma_recv_mgmt(ni, m0, subtype, rssi, nf);
}
/*
* Update TDMA state on receipt of a beacon frame with
* a TDMA information element. The sender's identity
* is provided so we can track who our peer is. If pickslot
* is non-zero we scan the slot allocation state in the ie
* to locate a free slot for our use.
*/
static int
tdma_update(struct ieee80211vap *vap, const struct ieee80211_tdma_param *tdma,
struct ieee80211_node *ni, int pickslot)
{
struct ieee80211_tdma_state *ts = vap->iv_tdma;
int slot, slotlen, update;
KASSERT(vap->iv_caps & IEEE80211_C_TDMA,
("not a tdma vap, caps 0x%x", vap->iv_caps));
update = 0;
if (tdma->tdma_slotcnt != ts->tdma_slotcnt) {
if (!TDMA_SLOTCNT_VALID(tdma->tdma_slotcnt)) {
if (ppsratecheck(&ts->tdma_lastprint, &ts->tdma_fails, 1))
printf("%s: bad slot cnt %u\n",
__func__, tdma->tdma_slotcnt);
return 0;
}
update |= TDMA_UPDATE_SLOTCNT;
}
slotlen = le16toh(tdma->tdma_slotlen) * 100;
if (slotlen != ts->tdma_slotlen) {
if (!TDMA_SLOTLEN_VALID(slotlen)) {
if (ppsratecheck(&ts->tdma_lastprint, &ts->tdma_fails, 1))
printf("%s: bad slot len %u\n",
__func__, slotlen);
return 0;
}
update |= TDMA_UPDATE_SLOTLEN;
}
if (tdma->tdma_bintval != ts->tdma_bintval) {
if (!TDMA_BINTVAL_VALID(tdma->tdma_bintval)) {
if (ppsratecheck(&ts->tdma_lastprint, &ts->tdma_fails, 1))
printf("%s: bad beacon interval %u\n",
__func__, tdma->tdma_bintval);
return 0;
}
update |= TDMA_UPDATE_BINTVAL;
}
slot = ts->tdma_slot;
if (pickslot) {
/*
* Pick unoccupied slot. Note we never choose slot 0.
*/
for (slot = tdma->tdma_slotcnt-1; slot > 0; slot--)
if (isclr(tdma->tdma_inuse, slot))
break;
if (slot <= 0) {
printf("%s: no free slot, slotcnt %u inuse: 0x%x\n",
__func__, tdma->tdma_slotcnt,
tdma->tdma_inuse[0]);
/* XXX need to do something better */
return 0;
}
if (slot != ts->tdma_slot)
update |= TDMA_UPDATE_SLOT;
}
if (ni != ts->tdma_peer) {
/* update everything */
update = TDMA_UPDATE_SLOT
| TDMA_UPDATE_SLOTCNT
| TDMA_UPDATE_SLOTLEN
| TDMA_UPDATE_BINTVAL;
}
if (update) {
/*
* New/changed parameters; update runtime state.
*/
/* XXX overwrites user parameters */
if (update & TDMA_UPDATE_SLOTCNT)
ts->tdma_slotcnt = tdma->tdma_slotcnt;
if (update & TDMA_UPDATE_SLOTLEN)
ts->tdma_slotlen = slotlen;
if (update & TDMA_UPDATE_SLOT)
ts->tdma_slot = slot;
if (update & TDMA_UPDATE_BINTVAL)
ts->tdma_bintval = tdma->tdma_bintval;
/* mark beacon to be updated before next xmit */
ieee80211_beacon_notify(vap, IEEE80211_BEACON_TDMA);
IEEE80211_DPRINTF(vap, IEEE80211_MSG_TDMA,
"%s: slot %u slotcnt %u slotlen %u us bintval %u\n",
__func__, ts->tdma_slot, ts->tdma_slotcnt,
ts->tdma_slotlen, ts->tdma_bintval);
}
/*
* Notify driver. Note we can be called before
* entering RUN state if we scanned and are
* joining an existing bss. In that case do not
* call the driver because not all necessary state
* has been setup. The next beacon will dtrt.
*/
if (vap->iv_state == IEEE80211_S_RUN)
vap->iv_ic->ic_tdma_update(ni, tdma, update);
/*
* Dispatch join event on first beacon from new master.
*/
if (ts->tdma_peer != ni) {
if (ts->tdma_peer != NULL)
ieee80211_notify_node_leave(vap->iv_bss);
ieee80211_notify_node_join(ni, 1);
/* NB: no reference, we just use the address */
ts->tdma_peer = ni;
}
return 1;
}
/*
* Process received TDMA parameters.
*/
static int
tdma_process_params(struct ieee80211_node *ni, const u_int8_t *ie,
int rssi, int nf, const struct ieee80211_frame *wh)
{
struct ieee80211vap *vap = ni->ni_vap;
struct ieee80211_tdma_state *ts = vap->iv_tdma;
const struct ieee80211_tdma_param *tdma =
(const struct ieee80211_tdma_param *) ie;
u_int len = ie[1];
KASSERT(vap->iv_caps & IEEE80211_C_TDMA,
("not a tdma vap, caps 0x%x", vap->iv_caps));
if (len < sizeof(*tdma) - 2) {
IEEE80211_DISCARD_IE(vap,
IEEE80211_MSG_ELEMID | IEEE80211_MSG_TDMA,
wh, "tdma", "too short, len %u", len);
return IEEE80211_REASON_IE_INVALID;
}
if (tdma->tdma_version != ts->tdma_version) {
IEEE80211_DISCARD_IE(vap,
IEEE80211_MSG_ELEMID | IEEE80211_MSG_TDMA,
wh, "tdma", "bad version %u (ours %u)",
tdma->tdma_version, ts->tdma_version);
return IEEE80211_REASON_IE_INVALID;
}
/*
* NB: ideally we'd check against tdma_slotcnt, but that
* would require extra effort so do this easy check that
* covers the work below; more stringent checks are done
* before we make more extensive use of the ie contents.
*/
if (tdma->tdma_slot >= TDMA_MAXSLOTS) {
IEEE80211_DISCARD_IE(vap,
IEEE80211_MSG_ELEMID | IEEE80211_MSG_TDMA,
wh, "tdma", "invalid slot %u", tdma->tdma_slot);
return IEEE80211_REASON_IE_INVALID;
}
/*
* Can reach here while scanning, update
* operational state only in RUN state.
*/
if (vap->iv_state == IEEE80211_S_RUN) {
if (tdma->tdma_slot != ts->tdma_slot &&
isclr(ts->tdma_inuse, tdma->tdma_slot)) {
IEEE80211_NOTE(vap, IEEE80211_MSG_TDMA, ni,
"discovered in slot %u", tdma->tdma_slot);
setbit(ts->tdma_inuse, tdma->tdma_slot);
/* XXX dispatch event only when operating as master */
if (ts->tdma_slot == 0)
ieee80211_notify_node_join(ni, 1);
}
setbit(ts->tdma_active, tdma->tdma_slot);
if (tdma->tdma_slot == ts->tdma_slot-1) {
/*
* Slave tsf synchronization to station
* just before us in the schedule. The driver
* is responsible for copying the timestamp
* of the received beacon into our beacon
* frame so the sender can calculate round
* trip time. We cannot do that here because
* we don't know how to update our beacon frame.
*/
(void) tdma_update(vap, tdma, ni, 0);
/* XXX reschedule swbmiss timer on parameter change */
} else if (tdma->tdma_slot == ts->tdma_slot+1) {
uint64_t tstamp;
#if 0
uint32_t rstamp = (uint32_t) le64toh(rs->tsf);
int32_t rtt;
#endif
/*
* Use returned timstamp to calculate the
* roundtrip time.
*/
memcpy(&tstamp, tdma->tdma_tstamp, 8);
#if 0
/* XXX use only 15 bits of rstamp */
rtt = rstamp - (le64toh(tstamp) & 0x7fff);
if (rtt < 0)
rtt += 0x7fff;
/* XXX hack to quiet normal use */
IEEE80211_DPRINTF(vap, IEEE80211_MSG_DOT1X,
"tdma rtt %5u [rstamp %5u tstamp %llu]\n",
rtt, rstamp,
(unsigned long long) le64toh(tstamp));
#endif
} else if (tdma->tdma_slot == ts->tdma_slot &&
le64toh(ni->ni_tstamp.tsf) > vap->iv_bss->ni_tstamp.tsf) {
/*
* Station using the same slot as us and has
* been around longer than us; we must move.
* Note this can happen if stations do not
* see each other while scanning.
*/
IEEE80211_DPRINTF(vap, IEEE80211_MSG_TDMA,
"slot %u collision rxtsf %llu tsf %llu\n",
tdma->tdma_slot,
(unsigned long long) le64toh(ni->ni_tstamp.tsf),
vap->iv_bss->ni_tstamp.tsf);
setbit(ts->tdma_inuse, tdma->tdma_slot);
(void) tdma_update(vap, tdma, ni, 1);
}
}
return 0;
}
int
ieee80211_tdma_getslot(struct ieee80211vap *vap)
{
struct ieee80211_tdma_state *ts = vap->iv_tdma;
KASSERT(vap->iv_caps & IEEE80211_C_TDMA,
("not a tdma vap, caps 0x%x", vap->iv_caps));
return ts->tdma_slot;
}
/*
* Parse a TDMA ie on station join and use it to setup node state.
*/
void
ieee80211_parse_tdma(struct ieee80211_node *ni, const uint8_t *ie)
{
struct ieee80211vap *vap = ni->ni_vap;
if (vap->iv_caps & IEEE80211_C_TDMA) {
const struct ieee80211_tdma_param *tdma =
(const struct ieee80211_tdma_param *)ie;
struct ieee80211_tdma_state *ts = vap->iv_tdma;
/*
* Adopt TDMA configuration when joining an
* existing network.
*/
setbit(ts->tdma_inuse, tdma->tdma_slot);
(void) tdma_update(vap, tdma, ni, 1);
/*
* Propagate capabilities based on the local
* configuration and the remote station's advertised
* capabilities. In particular this permits us to
* enable use of QoS to disable ACK's.
*/
if ((vap->iv_flags & IEEE80211_F_WME) &&
ni->ni_ies.wme_ie != NULL)
ni->ni_flags |= IEEE80211_NODE_QOS;
}
}
#define TDMA_OUI_BYTES 0x00, 0x03, 0x7f
/*
* Add a TDMA parameters element to a frame.
*/
uint8_t *
ieee80211_add_tdma(uint8_t *frm, struct ieee80211vap *vap)
{
#define ADDSHORT(frm, v) do { \
frm[0] = (v) & 0xff; \
frm[1] = (v) >> 8; \
frm += 2; \
} while (0)
static const struct ieee80211_tdma_param param = {
.tdma_id = IEEE80211_ELEMID_VENDOR,
.tdma_len = sizeof(struct ieee80211_tdma_param) - 2,
.tdma_oui = { TDMA_OUI_BYTES },
.tdma_type = TDMA_OUI_TYPE,
.tdma_subtype = TDMA_SUBTYPE_PARAM,
.tdma_version = TDMA_VERSION,
};
const struct ieee80211_tdma_state *ts = vap->iv_tdma;
uint16_t slotlen;
KASSERT(vap->iv_caps & IEEE80211_C_TDMA,
("not a tdma vap, caps 0x%x", vap->iv_caps));
memcpy(frm, &param, sizeof(param));
frm += __offsetof(struct ieee80211_tdma_param, tdma_slot);
*frm++ = ts->tdma_slot;
*frm++ = ts->tdma_slotcnt;
/* NB: convert units to fit in 16-bits */
slotlen = ts->tdma_slotlen / 100; /* 100us units */
ADDSHORT(frm, slotlen);
*frm++ = ts->tdma_bintval;
*frm++ = ts->tdma_inuse[0];
frm += 10; /* pad+timestamp */
return frm;
#undef ADDSHORT
}
#undef TDMA_OUI_BYTES
/*
* Update TDMA state at TBTT.
*/
void
ieee80211_tdma_update_beacon(struct ieee80211vap *vap,
struct ieee80211_beacon_offsets *bo)
{
struct ieee80211_tdma_state *ts = vap->iv_tdma;
KASSERT(vap->iv_caps & IEEE80211_C_TDMA,
("not a tdma vap, caps 0x%x", vap->iv_caps));
if (isset(bo->bo_flags, IEEE80211_BEACON_TDMA)) {
(void) ieee80211_add_tdma(bo->bo_tdma, vap);
clrbit(bo->bo_flags, IEEE80211_BEACON_TDMA);
}
if (ts->tdma_slot != 0) /* only on master */
return;
if (ts->tdma_count <= 0) {
/*
* Time to update the mask of active/inuse stations.
* We track stations that we've received a beacon
* frame from and update this mask periodically.
* This allows us to miss a few beacons before marking
* a slot free for re-use.
*/
ts->tdma_inuse[0] = ts->tdma_active[0];
ts->tdma_active[0] = 0x01;
/* update next time 'round */
/* XXX use notify framework */
setbit(bo->bo_flags, IEEE80211_BEACON_TDMA);
/* NB: use s/w beacon miss threshold; may be too high */
ts->tdma_count = vap->iv_bmissthreshold-1;
} else
ts->tdma_count--;
}
static int
tdma_ioctl_get80211(struct ieee80211vap *vap, struct ieee80211req *ireq)
{
struct ieee80211_tdma_state *ts = vap->iv_tdma;
if ((vap->iv_caps & IEEE80211_C_TDMA) == 0)
return EOPNOTSUPP;
switch (ireq->i_type) {
case IEEE80211_IOC_TDMA_SLOT:
ireq->i_val = ts->tdma_slot;
break;
case IEEE80211_IOC_TDMA_SLOTCNT:
ireq->i_val = ts->tdma_slotcnt;
break;
case IEEE80211_IOC_TDMA_SLOTLEN:
ireq->i_val = ts->tdma_slotlen;
break;
case IEEE80211_IOC_TDMA_BINTERVAL:
ireq->i_val = ts->tdma_bintval;
break;
default:
return ENOSYS;
}
return 0;
}
IEEE80211_IOCTL_GET(tdma, tdma_ioctl_get80211);
static int
tdma_ioctl_set80211(struct ieee80211vap *vap, struct ieee80211req *ireq)
{
struct ieee80211_tdma_state *ts = vap->iv_tdma;
if ((vap->iv_caps & IEEE80211_C_TDMA) == 0)
return EOPNOTSUPP;
switch (ireq->i_type) {
case IEEE80211_IOC_TDMA_SLOT:
if (!(0 <= ireq->i_val && ireq->i_val <= ts->tdma_slotcnt))
return EINVAL;
if (ireq->i_val != ts->tdma_slot) {
ts->tdma_slot = ireq->i_val;
goto restart;
}
break;
case IEEE80211_IOC_TDMA_SLOTCNT:
if (!TDMA_SLOTCNT_VALID(ireq->i_val))
return EINVAL;
if (ireq->i_val != ts->tdma_slotcnt) {
ts->tdma_slotcnt = ireq->i_val;
goto restart;
}
break;
case IEEE80211_IOC_TDMA_SLOTLEN:
/*
* XXX
* 150 insures at least 1/8 TU
* 0xfffff is the max duration for bursting
* (implict by way of 16-bit data type for i_val)
*/
if (!TDMA_SLOTLEN_VALID(ireq->i_val))
return EINVAL;
if (ireq->i_val != ts->tdma_slotlen) {
ts->tdma_slotlen = ireq->i_val;
goto restart;
}
break;
case IEEE80211_IOC_TDMA_BINTERVAL:
if (!TDMA_BINTVAL_VALID(ireq->i_val))
return EINVAL;
if (ireq->i_val != ts->tdma_bintval) {
ts->tdma_bintval = ireq->i_val;
goto restart;
}
break;
default:
return ENOSYS;
}
return 0;
restart:
ieee80211_beacon_notify(vap, IEEE80211_BEACON_TDMA);
return ERESTART;
}
IEEE80211_IOCTL_SET(tdma, tdma_ioctl_set80211);
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