net/ppp/ppp_async.c

97 static int ppp_async_encode(struct asyncppp *ap);
99 static int ppp_async_push(struct asyncppp *ap);
100 static void ppp_async_flush_output(struct asyncppp *ap);
101 static void ppp_async_input(struct asyncppp *ap, const unsigned char *buf,
107 static void async_lcp_peek(struct asyncppp *ap, unsigned char *data,
135 	struct asyncppp *ap;
138 	ap = tty->disc_data;
139 	if (ap != NULL)
140 		refcount_inc(&ap->refcnt);
142 	return ap;
145 static void ap_put(struct asyncppp *ap)
147 	if (refcount_dec_and_test(&ap->refcnt))
148 		complete(&ap->dead);
158 	struct asyncppp *ap;
166 	ap = kzalloc(sizeof(*ap), GFP_KERNEL);
167 	if (!ap)
171 	ap->tty = tty;
172 	ap->mru = PPP_MRU;
173 	spin_lock_init(&ap->xmit_lock);
174 	spin_lock_init(&ap->recv_lock);
175 	ap->xaccm[0] = ~0U;
176 	ap->xaccm[3] = 0x60000000U;
177 	ap->raccm = ~0U;
178 	ap->optr = ap->obuf;
179 	ap->olim = ap->obuf;
180 	ap->lcp_fcs = -1;
182 	skb_queue_head_init(&ap->rqueue);
183 	tasklet_setup(&ap->tsk, ppp_async_process);
185 	refcount_set(&ap->refcnt, 1);
186 	init_completion(&ap->dead);
188 	ap->chan.private = ap;
189 	ap->chan.ops = &async_ops;
190 	ap->chan.mtu = PPP_MRU;
192 	ap->chan.speed = speed;
193 	err = ppp_register_channel(&ap->chan);
197 	tty->disc_data = ap;
202 	kfree(ap);
218 	struct asyncppp *ap;
221 	ap = tty->disc_data;
224 	if (!ap)
228 	 * We have now ensured that nobody can start using ap from now
234 	if (!refcount_dec_and_test(&ap->refcnt))
235 		wait_for_completion(&ap->dead);
236 	tasklet_kill(&ap->tsk);
238 	ppp_unregister_channel(&ap->chan);
239 	kfree_skb(ap->rpkt);
240 	skb_queue_purge(&ap->rqueue);
241 	kfree_skb(ap->tpkt);
242 	kfree(ap);
286 	struct asyncppp *ap = ap_get(tty);
290 	if (!ap)
296 		if (put_user(ppp_channel_index(&ap->chan), p))
303 		if (put_user(ppp_unit_number(&ap->chan), p))
311 			ppp_async_flush_output(ap);
327 	ap_put(ap);
336 	struct asyncppp *ap = ap_get(tty);
339 	if (!ap)
341 	spin_lock_irqsave(&ap->recv_lock, flags);
342 	ppp_async_input(ap, buf, cflags, count);
343 	spin_unlock_irqrestore(&ap->recv_lock, flags);
344 	if (!skb_queue_empty(&ap->rqueue))
345 		tasklet_schedule(&ap->tsk);
346 	ap_put(ap);
353 	struct asyncppp *ap = ap_get(tty);
356 	if (!ap)
358 	set_bit(XMIT_WAKEUP, &ap->xmit_flags);
359 	tasklet_schedule(&ap->tsk);
360 	ap_put(ap);
396 	struct asyncppp *ap = chan->private;
405 		val = ap->flags | ap->rbits;
413 		ap->flags = val & ~SC_RCV_BITS;
414 		spin_lock_irq(&ap->recv_lock);
415 		ap->rbits = val & SC_RCV_BITS;
416 		spin_unlock_irq(&ap->recv_lock);
421 		if (put_user(ap->xaccm[0], (u32 __user *)argp))
426 		if (get_user(ap->xaccm[0], (u32 __user *)argp))
432 		if (put_user(ap->raccm, (u32 __user *)argp))
437 		if (get_user(ap->raccm, (u32 __user *)argp))
443 		if (copy_to_user(argp, ap->xaccm, sizeof(ap->xaccm)))
452 		memcpy(ap->xaccm, accm, sizeof(ap->xaccm));
457 		if (put_user(ap->mru, p))
470 		ap->mru = val;
488 	struct asyncppp *ap = from_tasklet(ap, t, tsk);
492 	while ((skb = skb_dequeue(&ap->rqueue)) != NULL) {
494 			ppp_input_error(&ap->chan, 0);
495 		ppp_input(&ap->chan, skb);
499 	if (test_bit(XMIT_WAKEUP, &ap->xmit_flags) && ppp_async_push(ap))
500 		ppp_output_wakeup(&ap->chan);
511  * Assumes ap->tpkt != 0 on entry.
515 #define PUT_BYTE(ap, buf, c, islcp)	do {		\
516 	if ((islcp && c < 0x20) || (ap->xaccm[c >> 5] & (1 << (c & 0x1f)))) {\
524 ppp_async_encode(struct asyncppp *ap)
531 	buf = ap->obuf;
532 	ap->olim = buf;
533 	ap->optr = buf;
534 	i = ap->tpkt_pos;
535 	data = ap->tpkt->data;
536 	count = ap->tpkt->len;
537 	fcs = ap->tfcs;
549 			async_lcp_peek(ap, data, count, 0);
556 		    time_after_eq(jiffies, ap->last_xmit + flag_time))
558 		ap->last_xmit = jiffies;
564 		if ((ap->flags & SC_COMP_AC) == 0 || islcp) {
565 			PUT_BYTE(ap, buf, 0xff, islcp);
567 			PUT_BYTE(ap, buf, 0x03, islcp);
577 	buflim = ap->obuf + OBUFSIZE - 6;
580 		if (i == 1 && c == 0 && (ap->flags & SC_COMP_PROT))
583 		PUT_BYTE(ap, buf, c, islcp);
590 		ap->olim = buf;
591 		ap->tpkt_pos = i;
592 		ap->tfcs = fcs;
601 	PUT_BYTE(ap, buf, c, islcp);
603 	PUT_BYTE(ap, buf, c, islcp);
605 	ap->olim = buf;
607 	consume_skb(ap->tpkt);
608 	ap->tpkt = NULL;
625 	struct asyncppp *ap = chan->private;
627 	ppp_async_push(ap);
629 	if (test_and_set_bit(XMIT_FULL, &ap->xmit_flags))
631 	ap->tpkt = skb;
632 	ap->tpkt_pos = 0;
634 	ppp_async_push(ap);
642 ppp_async_push(struct asyncppp *ap)
645 	struct tty_struct *tty = ap->tty;
657 	if (test_and_set_bit(XMIT_BUSY, &ap->xmit_flags))
659 	spin_lock_bh(&ap->xmit_lock);
661 		if (test_and_clear_bit(XMIT_WAKEUP, &ap->xmit_flags))
663 		if (!tty_stuffed && ap->optr < ap->olim) {
664 			avail = ap->olim - ap->optr;
666 			sent = tty->ops->write(tty, ap->optr, avail);
669 			ap->optr += sent;
674 		if (ap->optr >= ap->olim && ap->tpkt) {
675 			if (ppp_async_encode(ap)) {
676 				/* finished processing ap->tpkt */
677 				clear_bit(XMIT_FULL, &ap->xmit_flags);
691 		clear_bit(XMIT_BUSY, &ap->xmit_flags);
693 		if (!(test_bit(XMIT_WAKEUP, &ap->xmit_flags) ||
694 		      (!tty_stuffed && ap->tpkt)))
697 		if (test_and_set_bit(XMIT_BUSY, &ap->xmit_flags))
700 	spin_unlock_bh(&ap->xmit_lock);
704 	clear_bit(XMIT_BUSY, &ap->xmit_flags);
705 	if (ap->tpkt) {
706 		kfree_skb(ap->tpkt);
707 		ap->tpkt = NULL;
708 		clear_bit(XMIT_FULL, &ap->xmit_flags);
711 	ap->optr = ap->olim;
712 	spin_unlock_bh(&ap->xmit_lock);
722 ppp_async_flush_output(struct asyncppp *ap)
726 	spin_lock_bh(&ap->xmit_lock);
727 	ap->optr = ap->olim;
728 	if (ap->tpkt != NULL) {
729 		kfree_skb(ap->tpkt);
730 		ap->tpkt = NULL;
731 		clear_bit(XMIT_FULL, &ap->xmit_flags);
734 	spin_unlock_bh(&ap->xmit_lock);
736 		ppp_output_wakeup(&ap->chan);
745 scan_ordinary(struct asyncppp *ap, const unsigned char *buf, int count)
752 		    (c < 0x20 && (ap->raccm & (1 << c)) != 0))
760 process_input_packet(struct asyncppp *ap)
766 	skb = ap->rpkt;
767 	if (ap->state & (SC_TOSS | SC_ESCAPE))
802 			async_lcp_peek(ap, p, skb->len, 1);
806 	skb->cb[0] = ap->state;
807 	skb_queue_tail(&ap->rqueue, skb);
808 	ap->rpkt = NULL;
809 	ap->state = 0;
814 	ap->state = SC_PREV_ERROR;
826 ppp_async_input(struct asyncppp *ap, const u8 *buf, const u8 *flags, int count)
833 	if (~ap->rbits & SC_RCV_BITS) {
843 		ap->rbits |= s;
848 		if ((ap->state & SC_ESCAPE) && buf[0] == PPP_ESCAPE)
851 			n = scan_ordinary(ap, buf, count);
854 		if (flags && (ap->state & SC_TOSS) == 0) {
862 			ap->state |= SC_TOSS;
864 		} else if (n > 0 && (ap->state & SC_TOSS) == 0) {
866 			skb = ap->rpkt;
868 				skb = dev_alloc_skb(ap->mru + PPP_HDRLEN + 2);
871 				ap->rpkt = skb;
885 				ap->state |= SC_TOSS;
888 				if (ap->state & SC_ESCAPE) {
890 					ap->state &= ~SC_ESCAPE;
900 			ap->state |= SC_TOSS;
902 			process_input_packet(ap);
904 			ap->state |= SC_ESCAPE;
905 		} else if (I_IXON(ap->tty)) {
906 			if (c == START_CHAR(ap->tty))
907 				start_tty(ap->tty);
908 			else if (c == STOP_CHAR(ap->tty))
909 				stop_tty(ap->tty);
923 	ap->state |= SC_TOSS;
944 static void async_lcp_peek(struct asyncppp *ap, unsigned char *data,
972 			ap->lcp_fcs = fcs;
977 		fcs ^= ap->lcp_fcs;
978 		ap->lcp_fcs = -1;
993 				ap->mru = val;
995 				ap->chan.mtu = val;
1000 				ap->raccm = val;
1002 				ap->xaccm[0] = val;