net/ppp/ppp_generic.c

263 static void ppp_channel_push(struct channel *pch);
265 			      struct channel *pch);
272 				struct channel *pch);
287 static int ppp_connect_channel(struct channel *pch, int unit);
288 static int ppp_disconnect_channel(struct channel *pch);
289 static void ppp_destroy_channel(struct channel *pch);
626 static int ppp_bridge_channels(struct channel *pch, struct channel *pchb)
628 	write_lock_bh(&pch->upl);
629 	if (pch->ppp ||
630 	    rcu_dereference_protected(pch->bridge, lockdep_is_held(&pch->upl))) {
631 		write_unlock_bh(&pch->upl);
635 	rcu_assign_pointer(pch->bridge, pchb);
636 	write_unlock_bh(&pch->upl);
644 	refcount_inc(&pch->file.refcnt);
645 	rcu_assign_pointer(pchb->bridge, pch);
651 	write_lock_bh(&pch->upl);
652 	/* Re-read pch->bridge with upl held in case it was modified concurrently */
653 	pchb = rcu_dereference_protected(pch->bridge, lockdep_is_held(&pch->upl));
654 	RCU_INIT_POINTER(pch->bridge, NULL);
655 	write_unlock_bh(&pch->upl);
665 static int ppp_unbridge_channels(struct channel *pch)
669 	write_lock_bh(&pch->upl);
670 	pchb = rcu_dereference_protected(pch->bridge, lockdep_is_held(&pch->upl));
672 		write_unlock_bh(&pch->upl);
675 	RCU_INIT_POINTER(pch->bridge, NULL);
676 	write_unlock_bh(&pch->upl);
678 	/* Only modify pchb if phcb->bridge points back to pch.
685 	if (pchbb == pch)
691 	if (pchbb == pch)
692 		if (refcount_dec_and_test(&pch->file.refcnt))
693 			ppp_destroy_channel(pch);
736 		struct channel *pch, *pchb;
740 		pch = PF_TO_CHANNEL(pf);
746 			err = ppp_connect_channel(pch, unit);
750 			err = ppp_disconnect_channel(pch);
768 			err = ppp_bridge_channels(pch, pchb);
775 			err = ppp_unbridge_channels(pch);
779 			down_read(&pch->chan_sem);
780 			chan = pch->chan;
784 			up_read(&pch->chan_sem);
1585 	struct channel *pch;
1593 	pch = list_first_entry(&ppp->channels, struct channel, clist);
1594 	chan = pch->chan;
1862 	struct channel *pch;
1879 		pch = list_entry(list, struct channel, clist);
1881 		spin_lock(&pch->downl);
1882 		if (pch->chan) {
1883 			if (pch->chan->ops->start_xmit(pch->chan, skb))
1890 		spin_unlock(&pch->downl);
1926 	struct channel *pch;
1940 	list_for_each_entry(pch, &ppp->channels, clist) {
1941 		if (pch->chan) {
1942 			pch->avail = 1;
1944 			pch->speed = pch->chan->speed;
1946 			pch->avail = 0;
1948 		if (pch->avail) {
1949 			if (skb_queue_empty(&pch->file.xq) ||
1950 				!pch->had_frag) {
1951 					if (pch->speed == 0)
1954 						totspeed += pch->speed;
1956 					pch->avail = 2;
1960 			if (!pch->had_frag && i < ppp->nxchan)
2003 		pch = list_entry(list, struct channel, clist);
2005 		if (!pch->avail)
2012 		if (pch->avail == 1) {
2016 			pch->avail = 1;
2020 		spin_lock(&pch->downl);
2021 		if (pch->chan == NULL) {
2023 			if (pch->speed == 0)
2026 				totspeed -= pch->speed;
2028 			spin_unlock(&pch->downl);
2029 			pch->avail = 0;
2046 			if (pch->speed == 0) {
2054 					((totspeed*totfree)/pch->speed)) - hdrlen;
2056 					flen += ((totfree - nzero)*pch->speed)/totspeed;
2057 					nbigger -= ((totfree - nzero)*pch->speed)/
2078 			pch->avail = 2;
2079 			spin_unlock(&pch->downl);
2088 		mtu = pch->chan->mtu - (hdrlen - 2);
2115 		chan = pch->chan;
2116 		if (!skb_queue_empty(&pch->file.xq) ||
2118 			skb_queue_tail(&pch->file.xq, frag);
2119 		pch->had_frag = 1;
2124 		spin_unlock(&pch->downl);
2131 	spin_unlock(&pch->downl);
2141 static void __ppp_channel_push(struct channel *pch)
2146 	spin_lock(&pch->downl);
2147 	if (pch->chan) {
2148 		while (!skb_queue_empty(&pch->file.xq)) {
2149 			skb = skb_dequeue(&pch->file.xq);
2150 			if (!pch->chan->ops->start_xmit(pch->chan, skb)) {
2152 				skb_queue_head(&pch->file.xq, skb);
2158 		skb_queue_purge(&pch->file.xq);
2160 	spin_unlock(&pch->downl);
2162 	if (skb_queue_empty(&pch->file.xq)) {
2163 		ppp = pch->ppp;
2169 static void ppp_channel_push(struct channel *pch)
2171 	read_lock_bh(&pch->upl);
2172 	if (pch->ppp) {
2173 		(*this_cpu_ptr(pch->ppp->xmit_recursion))++;
2174 		__ppp_channel_push(pch);
2175 		(*this_cpu_ptr(pch->ppp->xmit_recursion))--;
2177 		__ppp_channel_push(pch);
2179 	read_unlock_bh(&pch->upl);
2193 ppp_do_recv(struct ppp *ppp, struct sk_buff *skb, struct channel *pch)
2197 		ppp_receive_frame(ppp, skb, pch);
2248 static bool ppp_channel_bridge_input(struct channel *pch, struct sk_buff *skb)
2253 	pchb = rcu_dereference(pch->bridge);
2264 	skb_scrub_packet(skb, !net_eq(pch->chan_net, pchb->chan_net));
2280 	struct channel *pch = chan->ppp;
2283 	if (!pch) {
2289 	if (ppp_channel_bridge_input(pch, skb))
2292 	read_lock_bh(&pch->upl);
2295 		if (pch->ppp) {
2296 			++pch->ppp->dev->stats.rx_length_errors;
2297 			ppp_receive_error(pch->ppp);
2303 	if (!pch->ppp || proto >= 0xc000 || proto == PPP_CCPFRAG) {
2305 		skb_queue_tail(&pch->file.rq, skb);
2307 		while (pch->file.rq.qlen > PPP_MAX_RQLEN &&
2308 		       (skb = skb_dequeue(&pch->file.rq)))
2310 		wake_up_interruptible(&pch->file.rwait);
2312 		ppp_do_recv(pch->ppp, skb, pch);
2316 	read_unlock_bh(&pch->upl);
2323 	struct channel *pch = chan->ppp;
2326 	if (!pch)
2329 	read_lock_bh(&pch->upl);
2330 	if (pch->ppp) {
2335 			ppp_do_recv(pch->ppp, skb, pch);
2338 	read_unlock_bh(&pch->upl);
2346 ppp_receive_frame(struct ppp *ppp, struct sk_buff *skb, struct channel *pch)
2354 			ppp_receive_mp_frame(ppp, skb, pch);
2590 ppp_receive_mp_frame(struct ppp *ppp, struct sk_buff *skb, struct channel *pch)
2628 	pch->lastseq = seq;
2879 	struct channel *pch;
2882 	pch = kzalloc(sizeof(struct channel), GFP_KERNEL);
2883 	if (!pch)
2888 	pch->ppp = NULL;
2889 	pch->chan = chan;
2890 	pch->chan_net = get_net_track(net, &pch->ns_tracker, GFP_KERNEL);
2891 	chan->ppp = pch;
2892 	init_ppp_file(&pch->file, CHANNEL);
2893 	pch->file.hdrlen = chan->hdrlen;
2895 	pch->lastseq = -1;
2897 	init_rwsem(&pch->chan_sem);
2898 	spin_lock_init(&pch->downl);
2899 	rwlock_init(&pch->upl);
2902 	pch->file.index = ++pn->last_channel_index;
2903 	list_add(&pch->list, &pn->new_channels);
2915 	struct channel *pch = chan->ppp;
2917 	if (pch)
2918 		return pch->file.index;
2927 	struct channel *pch = chan->ppp;
2930 	if (pch) {
2931 		read_lock_bh(&pch->upl);
2932 		if (pch->ppp)
2933 			unit = pch->ppp->file.index;
2934 		read_unlock_bh(&pch->upl);
2944 	struct channel *pch = chan->ppp;
2947 	if (pch) {
2948 		read_lock_bh(&pch->upl);
2949 		if (pch->ppp && pch->ppp->dev)
2950 			name = pch->ppp->dev->name;
2951 		read_unlock_bh(&pch->upl);
2964 	struct channel *pch = chan->ppp;
2967 	if (!pch)
2976 	down_write(&pch->chan_sem);
2977 	spin_lock_bh(&pch->downl);
2978 	pch->chan = NULL;
2979 	spin_unlock_bh(&pch->downl);
2980 	up_write(&pch->chan_sem);
2981 	ppp_disconnect_channel(pch);
2983 	pn = ppp_pernet(pch->chan_net);
2985 	list_del(&pch->list);
2988 	ppp_unbridge_channels(pch);
2990 	pch->file.dead = 1;
2991 	wake_up_interruptible(&pch->file.rwait);
2993 	if (refcount_dec_and_test(&pch->file.refcnt))
2994 		ppp_destroy_channel(pch);
3004 	struct channel *pch = chan->ppp;
3006 	if (!pch)
3008 	ppp_channel_push(pch);
3429 	struct channel *pch;
3431 	list_for_each_entry(pch, &pn->new_channels, list) {
3432 		if (pch->file.index == unit) {
3433 			list_move(&pch->list, &pn->all_channels);
3434 			return pch;
3438 	list_for_each_entry(pch, &pn->all_channels, list) {
3439 		if (pch->file.index == unit)
3440 			return pch;
3450 ppp_connect_channel(struct channel *pch, int unit)
3457 	pn = ppp_pernet(pch->chan_net);
3463 	write_lock_bh(&pch->upl);
3465 	if (pch->ppp ||
3466 	    rcu_dereference_protected(pch->bridge, lockdep_is_held(&pch->upl)))
3470 	spin_lock_bh(&pch->downl);
3471 	if (!pch->chan) {
3473 		spin_unlock_bh(&pch->downl);
3478 	spin_unlock_bh(&pch->downl);
3479 	if (pch->file.hdrlen > ppp->file.hdrlen)
3480 		ppp->file.hdrlen = pch->file.hdrlen;
3481 	hdrlen = pch->file.hdrlen + 2;	/* for protocol bytes */
3484 	list_add_tail(&pch->clist, &ppp->channels);
3486 	pch->ppp = ppp;
3492 	write_unlock_bh(&pch->upl);
3502 ppp_disconnect_channel(struct channel *pch)
3507 	write_lock_bh(&pch->upl);
3508 	ppp = pch->ppp;
3509 	pch->ppp = NULL;
3510 	write_unlock_bh(&pch->upl);
3514 		list_del(&pch->clist);
3528 static void ppp_destroy_channel(struct channel *pch)
3530 	put_net_track(pch->chan_net, &pch->ns_tracker);
3531 	pch->chan_net = NULL;
3535 	if (!pch->file.dead) {
3537 		pr_err("ppp: destroying undead channel %p !\n", pch);
3540 	skb_queue_purge(&pch->file.xq);
3541 	skb_queue_purge(&pch->file.rq);
3542 	kfree(pch);