isdnl2.c

linux-2.6.15.6

l2_got_ui(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;
	struct sk_buff *skb = arg;

	skb_pull(skb, l2headersize(&st->l2, 1));
	st->l2.l2l3(st, DL_UNIT_DATA | INDICATION, skb);
/*	^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 *		in states 1-3 for broadcast
 */


}

static void
l2_establish(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;

	establishlink(fi);
	test_and_set_bit(FLG_L3_INIT, &st->l2.flag);
}

static void
l2_discard_i_setl3(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;

	skb_queue_purge(&st->l2.i_queue);
	test_and_set_bit(FLG_L3_INIT, &st->l2.flag);
	test_and_clear_bit(FLG_PEND_REL, &st->l2.flag);
}

static void
l2_l3_reestablish(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;

	skb_queue_purge(&st->l2.i_queue);
	establishlink(fi);
	test_and_set_bit(FLG_L3_INIT, &st->l2.flag);
}

static void
l2_release(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;

	st->l2.l2l3(st, DL_RELEASE | CONFIRM, NULL);
}

static void
l2_pend_rel(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;

	test_and_set_bit(FLG_PEND_REL, &st->l2.flag);
}

static void
l2_disconnect(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;

	skb_queue_purge(&st->l2.i_queue);
	freewin(st);
	FsmChangeState(fi, ST_L2_6);
	st->l2.rc = 0;
	send_uframe(st, DISC | 0x10, CMD);
	FsmDelTimer(&st->l2.t203, 1);
	restart_t200(st, 2);
}

static void
l2_start_multi(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;
	struct sk_buff *skb = arg;

	send_uframe(st, UA | get_PollFlagFree(st, skb), RSP);

	clear_exception(&st->l2);
	st->l2.vs = 0;
	st->l2.va = 0;
	st->l2.vr = 0;
	st->l2.sow = 0;
	FsmChangeState(fi, ST_L2_7);
	FsmAddTimer(&st->l2.t203, st->l2.T203, EV_L2_T203, NULL, 3);

	st->l2.l2l3(st, DL_ESTABLISH | INDICATION, NULL);
}

static void
l2_send_UA(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;
	struct sk_buff *skb = arg;

	send_uframe(st, UA | get_PollFlagFree(st, skb), RSP);
}

static void
l2_send_DM(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;
	struct sk_buff *skb = arg;

	send_uframe(st, DM | get_PollFlagFree(st, skb), RSP);
}

static void
l2_restart_multi(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;
	struct sk_buff *skb = arg;
	int est = 0, state;

	state = fi->state;

	send_uframe(st, UA | get_PollFlagFree(st, skb), RSP);

	st->ma.layer(st, MDL_ERROR | INDICATION, (void *) 'F');

	if (st->l2.vs != st->l2.va) {
		skb_queue_purge(&st->l2.i_queue);
		est = 1;
	}

	clear_exception(&st->l2);
	st->l2.vs = 0;
	st->l2.va = 0;
	st->l2.vr = 0;
	st->l2.sow = 0;
	FsmChangeState(fi, ST_L2_7);
	stop_t200(st, 3);
	FsmRestartTimer(&st->l2.t203, st->l2.T203, EV_L2_T203, NULL, 3);

	if (est)
		st->l2.l2l3(st, DL_ESTABLISH | INDICATION, NULL);

	if ((ST_L2_7==state) || (ST_L2_8 == state))
		if (!skb_queue_empty(&st->l2.i_queue) && cansend(st))
			st->l2.l2l1(st, PH_PULL | REQUEST, NULL);
}

static void
l2_stop_multi(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;
	struct sk_buff *skb = arg;

	FsmChangeState(fi, ST_L2_4);
	FsmDelTimer(&st->l2.t203, 3);
	stop_t200(st, 4);

	send_uframe(st, UA | get_PollFlagFree(st, skb), RSP);

	skb_queue_purge(&st->l2.i_queue);
	freewin(st);
	lapb_dl_release_l2l3(st, INDICATION);
}

static void
l2_connected(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;
	struct sk_buff *skb = arg;
	int pr=-1;

	if (!get_PollFlag(st, skb)) {
		l2_mdl_error_ua(fi, event, arg);
		return;
	}
	dev_kfree_skb(skb);

	if (test_and_clear_bit(FLG_PEND_REL, &st->l2.flag))
		l2_disconnect(fi, event, arg);

	if (test_and_clear_bit(FLG_L3_INIT, &st->l2.flag)) {
		pr = DL_ESTABLISH | CONFIRM;
	} else if (st->l2.vs != st->l2.va) {
		skb_queue_purge(&st->l2.i_queue);
		pr = DL_ESTABLISH | INDICATION;
	}

	stop_t200(st, 5);

	st->l2.vr = 0;
	st->l2.vs = 0;
	st->l2.va = 0;
	st->l2.sow = 0;
	FsmChangeState(fi, ST_L2_7);
	FsmAddTimer(&st->l2.t203, st->l2.T203, EV_L2_T203, NULL, 4);

	if (pr != -1)
		st->l2.l2l3(st, pr, NULL);

	if (!skb_queue_empty(&st->l2.i_queue) && cansend(st))
		st->l2.l2l1(st, PH_PULL | REQUEST, NULL);
}

static void
l2_released(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;
	struct sk_buff *skb = arg;

	if (!get_PollFlag(st, skb)) {
		l2_mdl_error_ua(fi, event, arg);
		return;
	}
	dev_kfree_skb(skb);

	stop_t200(st, 6);
	lapb_dl_release_l2l3(st, CONFIRM);
	FsmChangeState(fi, ST_L2_4);
}

static void
l2_reestablish(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;
	struct sk_buff *skb = arg;

	if (!get_PollFlagFree(st, skb)) {
		establishlink(fi);
		test_and_set_bit(FLG_L3_INIT, &st->l2.flag);
	}
}

static void
l2_st5_dm_release(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;
	struct sk_buff *skb = arg;

	if (get_PollFlagFree(st, skb)) {
		stop_t200(st, 7);
	 	if (!test_bit(FLG_L3_INIT, &st->l2.flag))
			skb_queue_purge(&st->l2.i_queue);
		if (test_bit(FLG_LAPB, &st->l2.flag))
			st->l2.l2l1(st, PH_DEACTIVATE | REQUEST, NULL);
		st5_dl_release_l2l3(st);
		FsmChangeState(fi, ST_L2_4);
	}
}

static void
l2_st6_dm_release(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;
	struct sk_buff *skb = arg;

	if (get_PollFlagFree(st, skb)) {
		stop_t200(st, 8);
		lapb_dl_release_l2l3(st, CONFIRM);
		FsmChangeState(fi, ST_L2_4);
	}
}

static inline void
enquiry_cr(struct PStack *st, u_char typ, u_char cr, u_char pf)
{
	struct sk_buff *skb;
	struct Layer2 *l2;
	u_char tmp[MAX_HEADER_LEN];
	int i;

	l2 = &st->l2;
	i = sethdraddr(l2, tmp, cr);
	if (test_bit(FLG_MOD128, &l2->flag)) {
		tmp[i++] = typ;
		tmp[i++] = (l2->vr << 1) | (pf ? 1 : 0);
	} else
		tmp[i++] = (l2->vr << 5) | typ | (pf ? 0x10 : 0);
	if (!(skb = alloc_skb(i, GFP_ATOMIC))) {
		printk(KERN_WARNING "isdl2 can't alloc sbbuff for enquiry_cr\n");
		return;
	}
	memcpy(skb_put(skb, i), tmp, i);
	enqueue_super(st, skb);
}

static inline void
enquiry_response(struct PStack *st)
{
	if (test_bit(FLG_OWN_BUSY, &st->l2.flag))
		enquiry_cr(st, RNR, RSP, 1);
	else
		enquiry_cr(st, RR, RSP, 1);
	test_and_clear_bit(FLG_ACK_PEND, &st->l2.flag);
}

static inline void
transmit_enquiry(struct PStack *st)
{
	if (test_bit(FLG_OWN_BUSY, &st->l2.flag))
		enquiry_cr(st, RNR, CMD, 1);
	else
		enquiry_cr(st, RR, CMD, 1);
	test_and_clear_bit(FLG_ACK_PEND, &st->l2.flag);
	start_t200(st, 9);
}


static void
nrerrorrecovery(struct FsmInst *fi)
{
	struct PStack *st = fi->userdata;

	st->ma.layer(st, MDL_ERROR | INDICATION, (void *) 'J');
	establishlink(fi);
	test_and_clear_bit(FLG_L3_INIT, &st->l2.flag);
}

static void
invoke_retransmission(struct PStack *st, unsigned int nr)
{
	struct Layer2 *l2 = &st->l2;
	u_int p1;
	u_long flags;

	spin_lock_irqsave(&l2->lock, flags);
	if (l2->vs != nr) {
		while (l2->vs != nr) {
			(l2->vs)--;
			if(test_bit(FLG_MOD128, &l2->flag)) {
				l2->vs %= 128;
				p1 = (l2->vs - l2->va) % 128;
			} else {
				l2->vs %= 8;
				p1 = (l2->vs - l2->va) % 8;
			}
			p1 = (p1 + l2->sow) % l2->window;
			if (test_bit(FLG_LAPB, &l2->flag))
				st->l1.bcs->tx_cnt += l2->windowar[p1]->len + l2headersize(l2, 0);
			skb_queue_head(&l2->i_queue, l2->windowar[p1]);
			l2->windowar[p1] = NULL;
		}
		spin_unlock_irqrestore(&l2->lock, flags);
		st->l2.l2l1(st, PH_PULL | REQUEST, NULL);
		return;
	}
	spin_unlock_irqrestore(&l2->lock, flags);
}

static void
l2_st7_got_super(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;
	struct sk_buff *skb = arg;
	int PollFlag, rsp, typ = RR;
	unsigned int nr;
	struct Layer2 *l2 = &st->l2;

	rsp = *skb->data & 0x2;
	if (test_bit(FLG_ORIG, &l2->flag))
		rsp = !rsp;

	skb_pull(skb, l2addrsize(l2));
	if (IsRNR(skb->data, st)) {
		set_peer_busy(l2);
		typ = RNR;
	} else
		clear_peer_busy(l2);
	if (IsREJ(skb->data, st))
		typ = REJ;

	if (test_bit(FLG_MOD128, &l2->flag)) {
		PollFlag = (skb->data[1] & 0x1) == 0x1;
		nr = skb->data[1] >> 1;
	} else {
		PollFlag = (skb->data[0] & 0x10);
		nr = (skb->data[0] >> 5) & 0x7;
	}
	dev_kfree_skb(skb);

	if (PollFlag) {
		if (rsp)
			st->ma.layer(st, MDL_ERROR | INDICATION, (void *) 'A');
		else
			enquiry_response(st);
	}
	if (legalnr(st, nr)) {
		if (typ == REJ) {
			setva(st, nr);
			invoke_retransmission(st, nr);
			stop_t200(st, 10);
			if (FsmAddTimer(&st->l2.t203, st->l2.T203,
					EV_L2_T203, NULL, 6))
				l2m_debug(&st->l2.l2m, "Restart T203 ST7 REJ");
		} else if ((nr == l2->vs) && (typ == RR)) {
			setva(st, nr);
			stop_t200(st, 11);
			FsmRestartTimer(&st->l2.t203, st->l2.T203,
					EV_L2_T203, NULL, 7);
		} else if ((l2->va != nr) || (typ == RNR)) {
			setva(st, nr);
			if(typ != RR) FsmDelTimer(&st->l2.t203, 9);
			restart_t200(st, 12);
		}
		if (!skb_queue_empty(&st->l2.i_queue) && (typ == RR))
			st->l2.l2l1(st, PH_PULL | REQUEST, NULL);
	} else
		nrerrorrecovery(fi);
}

static void
l2_feed_i_if_reest(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;
	struct sk_buff *skb = arg;

	if (test_bit(FLG_LAPB, &st->l2.flag))
		st->l1.bcs->tx_cnt += skb->len + l2headersize(&st->l2, 0);
	if (!test_bit(FLG_L3_INIT, &st->l2.flag))
		skb_queue_tail(&st->l2.i_queue, skb);
	else
		dev_kfree_skb(skb);
}

static void
l2_feed_i_pull(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;
	struct sk_buff *skb = arg;

	if (test_bit(FLG_LAPB, &st->l2.flag))
		st->l1.bcs->tx_cnt += skb->len + l2headersize(&st->l2, 0);
	skb_queue_tail(&st->l2.i_queue, skb);
	st->l2.l2l1(st, PH_PULL | REQUEST, NULL);
}

static void
l2_feed_iqueue(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;
	struct sk_buff *skb = arg;

	if (test_bit(FLG_LAPB, &st->l2.flag))
		st->l1.bcs->tx_cnt += skb->len + l2headersize(&st->l2, 0);
	skb_queue_tail(&st->l2.i_queue, skb);
}

static void
l2_got_iframe(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;
	struct sk_buff *skb = arg;
	struct Layer2 *l2 = &(st->l2);
	int PollFlag, ns, i;
	unsigned int nr;

	i = l2addrsize(l2);
	if (test_bit(FLG_MOD128, &l2->flag)) {
		PollFlag = ((skb->data[i + 1] & 0x1) == 0x1);
		ns = skb->data[i] >> 1;
		nr = (skb->data[i + 1] >> 1) & 0x7f;
	} else {
		PollFlag = (skb->data[i] & 0x10);
		ns = (skb->data[i] >> 1) & 0x7;
		nr = (skb->data[i] >> 5) & 0x7;
	}
	if (test_bit(FLG_OWN_BUSY, &l2->flag)) {
		dev_kfree_skb(skb);
		if(PollFlag) enquiry_response(st);
	} else if (l2->vr == ns) {
		(l2->vr)++;
		if(test_bit(FLG_MOD128, &l2->flag))
			l2->vr %= 128;
		else
			l2->vr %= 8;
		test_and_clear_bit(FLG_REJEXC, &l2->flag);

		if (PollFlag)
			enquiry_response(st);
		else
			test_and_set_bit(FLG_ACK_PEND, &l2->flag);
		skb_pull(skb, l2headersize(l2, 0));
		st->l2.l2l3(st, DL_DATA | INDICATION, skb);
	} else {
		/* n(s)!=v(r) */
		dev_kfree_skb(skb);
		if (test_and_set_bit(FLG_REJEXC, &l2->flag)) {
			if (PollFlag)
				enquiry_response(st);
		} else {
			enquiry_cr(st, REJ, RSP, PollFlag);
			test_and_clear_bit(FLG_ACK_PEND, &l2->flag);
		}
	}

	if (legalnr(st, nr)) {
		if (!test_bit(FLG_PEER_BUSY, &st->l2.flag) && (fi->state == ST_L2_7)) {
			if (nr == st->l2.vs) {
				stop_t200(st, 13);
				FsmRestartTimer(&st->l2.t203, st->l2.T203,
						EV_L2_T203, NULL, 7);
			} else if (nr != st->l2.va)
				restart_t200(st, 14);
		}
		setva(st, nr);
	} else {
		nrerrorrecovery(fi);
		return;
	}

	if (!skb_queue_empty(&st->l2.i_queue) && (fi->state == ST_L2_7))
		st->l2.l2l1(st, PH_PULL | REQUEST, NULL);
	if (test_and_clear_bit(FLG_ACK_PEND, &st->l2.flag))
		enquiry_cr(st, RR, RSP, 0);
}

static void
l2_got_tei(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;

	st->l2.tei = (long) arg;

	if (fi->state == ST_L2_3) {
		establishlink(fi);
		test_and_set_bit(FLG_L3_INIT, &st->l2.flag);
	} else
		FsmChangeState(fi, ST_L2_4);
	if (!skb_queue_empty(&st->l2.ui_queue))
		tx_ui(st);
}

static void
l2_st5_tout_200(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;

	if (test_bit(FLG_LAPD, &st->l2.flag) &&
		test_bit(FLG_DCHAN_BUSY, &st->l2.flag)) {
		FsmAddTimer(&st->l2.t200, st->l2.T200, EV_L2_T200, NULL, 9);
	} else if (st->l2.rc == st->l2.N200) {
		FsmChangeState(fi, ST_L2_4);
		test_and_clear_bit(FLG_T200_RUN, &st->l2.flag);
		skb_queue_purge(&st->l2.i_queue);
		st->ma.layer(st, MDL_ERROR | INDICATION, (void *) 'G');
		if (test_bit(FLG_LAPB, &st->l2.flag))
			st->l2.l2l1(st, PH_DEACTIVATE | REQUEST, NULL);
		st5_dl_release_l2l3(st);
	} else {
		st->l2.rc++;
		FsmAddTimer(&st->l2.t200, st->l2.T200, EV_L2_T200, NULL, 9);
		send_uframe(st, (test_bit(FLG_MOD128, &st->l2.flag) ? SABME : SABM)
			    | 0x10, CMD);
	}
}

static void
l2_st6_tout_200(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;

	if (test_bit(FLG_LAPD, &st->l2.flag) &&
		test_bit(FLG_DCHAN_BUSY, &st->l2.flag)) {
		FsmAddTimer(&st->l2.t200, st->l2.T200, EV_L2_T200, NULL, 9);
	} else if (st->l2.rc == st->l2.N200) {
		FsmChangeState(fi, ST_L2_4);
		test_and_clear_bit(FLG_T200_RUN, &st->l2.flag);
		st->ma.layer(st, MDL_ERROR | INDICATION, (void *) 'H');
		lapb_dl_release_l2l3(st, CONFIRM);
	} else {
		st->l2.rc++;
		FsmAddTimer(&st->l2.t200, st->l2.T200, EV_L2_T200,
			    NULL, 9);
		send_uframe(st, DISC | 0x10, CMD);
	}
}

static void
l2_st7_tout_200(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;

	if (test_bit(FLG_LAPD, &st->l2.flag) &&
		test_bit(FLG_DCHAN_BUSY, &st->l2.flag)) {
		FsmAddTimer(&st->l2.t200, st->l2.T200, EV_L2_T200, NULL, 9);
		return;
	}
	test_and_clear_bit(FLG_T200_RUN, &st->l2.flag);
	st->l2.rc = 0;
	FsmChangeState(fi, ST_L2_8);

	transmit_enquiry(st);
	st->l2.rc++;
}

static void
l2_st8_tout_200(struct FsmInst *fi, int event, void *arg)
{
	struct PStack *st = fi->userdata;

	if (test_bit(FLG_LAPD, &st->l2.flag) &&
		test_bit(FLG_DCHAN_BUSY, &st->l2.flag)) {
		FsmAddTimer(&st->l2.t200, st->l2.T200, EV_L2_T200, NULL, 9);
		return;
	}
	test_and_clear_bit(FLG_T200_RUN, &st->l2.flag);
	if (st->l2.rc == st->l2.N200) {
		st->ma.layer(st, MDL_ERROR | INDICATION, (void *) 'I');
		establishlink(fi);
		test_and_clear_bit(FLG_L3_INIT, &st->l2.flag);
	} else {
		transmit_enquiry(st);
		st->l2.rc++;
	}
}

static void
l2_st7_tout_203(struct FsmInst *fi, int event, void *arg)
{