/*
* Age frames on the age queue. Ages are stored as time
* deltas (in seconds) relative to the head so we can check
* and/or adjust only the head of the list. If a frame's age
* exceeds the time quanta then remove it. The list of removed
* frames is is returned to the caller joined by m_nextpkt.
*/
struct mbuf *
ieee80211_ageq_age(struct ieee80211_ageq *aq, int quanta)
{
struct mbuf *head, **phead;
struct mbuf *m;
phead = &head;
if (aq->aq_len != 0) {
IEEE80211_AGEQ_LOCK(aq);
while ((m = aq->aq_head) != NULL && M_AGE_GET(m) < quanta) {
if ((aq->aq_head = m->m_nextpkt) == NULL)
aq->aq_tail = NULL;
KASSERT(aq->aq_len > 0, ("aq len %d", aq->aq_len));
aq->aq_len--;
/* add to private list for return */
*phead = m;
phead = &m->m_nextpkt;
}
if (m != NULL)
M_AGE_SUB(m, quanta);
IEEE80211_AGEQ_UNLOCK(aq);
}
*phead = NULL;
return head;
}
/*
* Append an mbuf to the ageq and mark it with the specified max age
* If the frame is not removed before the age (in seconds) expires
* then it is reclaimed (along with any node reference).
*/
int
ieee80211_ageq_append(struct ieee80211_ageq *aq, struct mbuf *m, int age)
{
IEEE80211_AGEQ_LOCK(aq);
if (__predict_true(aq->aq_len < aq->aq_maxlen)) {
if (aq->aq_tail == NULL) {
aq->aq_head = m;
} else {
aq->aq_tail->m_nextpkt = m;
age -= M_AGE_GET(aq->aq_head);
}
KASSERT(age >= 0, ("age %d", age));
M_AGE_SET(m, age);
m->m_nextpkt = NULL;
aq->aq_tail = m;
aq->aq_len++;
IEEE80211_AGEQ_UNLOCK(aq);
return 0;
} else {
/*
* No space, drop and cleanup references.
*/
aq->aq_drops++;
IEEE80211_AGEQ_UNLOCK(aq);
/* XXX tail drop? */
ageq_mfree(m);
return ENOSPC;
}
}
/*
* Age frames on the power save queue. The aging interval is
* 4 times the listen interval specified by the station. This
* number is factored into the age calculations when the frame
* is placed on the queue. We store ages as time differences
* so we can check and/or adjust only the head of the list.
* If a frame's age exceeds the threshold then discard it.
* The number of frames discarded is returned so the caller
* can check if it needs to adjust the tim.
*/
int
ieee80211_node_psq_age(struct ieee80211_node *ni)
{
struct ieee80211_psq *psq = &ni->ni_psq;
int discard = 0;
if (psq->psq_len != 0) {
#ifdef IEEE80211_DEBUG
struct ieee80211vap *vap = ni->ni_vap;
#endif
struct ieee80211_psq_head *qhead;
struct mbuf *m;
IEEE80211_PSQ_LOCK(psq);
qhead = &psq->psq_head[0];
again:
while ((m = qhead->head) != NULL &&
M_AGE_GET(m) < IEEE80211_INACT_WAIT) {
IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni,
"discard frame, age %u", M_AGE_GET(m));
if ((qhead->head = m->m_nextpkt) == NULL)
qhead->tail = NULL;
KASSERT(qhead->len > 0, ("qhead len %d", qhead->len));
qhead->len--;
KASSERT(psq->psq_len > 0, ("psq len %d", psq->psq_len));
psq->psq_len--;
psq_mfree(m);
discard++;
}
if (qhead == &psq->psq_head[0]) { /* Algol-68 style for loop */
qhead = &psq->psq_head[1];
goto again;
}
if (m != NULL)
M_AGE_SUB(m, IEEE80211_INACT_WAIT);
IEEE80211_PSQ_UNLOCK(psq);
IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni,
"discard %u frames for age", discard);
IEEE80211_NODE_STAT_ADD(ni, ps_discard, discard);
}
return discard;
}
/*
* Save an outbound packet for a node in power-save sleep state.
* The new packet is placed on the node's saved queue, and the TIM
* is changed, if necessary.
*/
int
ieee80211_pwrsave(struct ieee80211_node *ni, struct mbuf *m)
{
struct ieee80211_psq *psq = &ni->ni_psq;
struct ieee80211vap *vap = ni->ni_vap;
struct ieee80211com *ic = ni->ni_ic;
struct ieee80211_psq_head *qhead;
int qlen, age;
IEEE80211_PSQ_LOCK(psq);
if (psq->psq_len >= psq->psq_maxlen) {
psq->psq_drops++;
IEEE80211_PSQ_UNLOCK(psq);
IEEE80211_NOTE(vap, IEEE80211_MSG_ANY, ni,
"pwr save q overflow, drops %d (size %d)",
psq->psq_drops, psq->psq_len);
#ifdef IEEE80211_DEBUG
if (ieee80211_msg_dumppkts(vap))
ieee80211_dump_pkt(ni->ni_ic, mtod(m, caddr_t),
m->m_len, -1, -1);
#endif
psq_mfree(m);
return ENOSPC;
}
/*
* Tag the frame with it's expiry time and insert it in
* the appropriate queue. The aging interval is 4 times
* the listen interval specified by the station. Frames
* that sit around too long are reclaimed using this
* information.
*/
/* TU -> secs. XXX handle overflow? */
age = IEEE80211_TU_TO_MS((ni->ni_intval * ic->ic_bintval) << 2) / 1000;
/*
* Encapsulated frames go on the high priority queue,
* other stuff goes on the low priority queue. We use
* this to order frames returned out of the driver
* ahead of frames we collect in ieee80211_start.
*/
if (m->m_flags & M_ENCAP)
qhead = &psq->psq_head[0];
else
qhead = &psq->psq_head[1];
if (qhead->tail == NULL) {
struct mbuf *mh;
qhead->head = m;
/*
* Take care to adjust age when inserting the first
* frame of a queue and the other queue already has
* frames. We need to preserve the age difference
* relationship so ieee80211_node_psq_age works.
*/
if (qhead == &psq->psq_head[1]) {
mh = psq->psq_head[0].head;
if (mh != NULL)
age-= M_AGE_GET(mh);
} else {
mh = psq->psq_head[1].head;
if (mh != NULL) {
int nage = M_AGE_GET(mh) - age;
/* XXX is clamping to zero good 'nuf? */
M_AGE_SET(mh, nage < 0 ? 0 : nage);
}
}
} else {
qhead->tail->m_nextpkt = m;
age -= M_AGE_GET(qhead->head);
}
KASSERT(age >= 0, ("age %d", age));
M_AGE_SET(m, age);
m->m_nextpkt = NULL;
qhead->tail = m;
qhead->len++;
qlen = ++(psq->psq_len);
IEEE80211_PSQ_UNLOCK(psq);
IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni,
"save frame with age %d, %u now queued", age, qlen);
if (qlen == 1 && vap->iv_set_tim != NULL)
vap->iv_set_tim(ni, 1);
return 0;
}
