/*
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
 */
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/kernel.h>
#include <linux/timer.h>
#include <linux/string.h>
#include <linux/sockios.h>
#include <linux/net.h>
#include <linux/gfp.h>
#include <net/ax25.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <linux/fcntl.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <net/rose.h>

/*
 *	This procedure is passed a buffer descriptor for an iframe. It builds
 *	the rest of the control part of the frame and then writes it out.
 */
static void rose_send_iframe(struct sock *sk, struct sk_buff *skb)
{
	struct rose_sock *rose = rose_sk(sk);

	if (skb == NULL)
		return;

	skb->data[2] |= (rose->vr << 5) & 0xE0;
	skb->data[2] |= (rose->vs << 1) & 0x0E;

	rose_start_idletimer(sk);

	rose_transmit_link(skb, rose->neighbour);
}

void rose_kick(struct sock *sk)
{
	struct rose_sock *rose = rose_sk(sk);
	struct sk_buff *skb, *skbn;
	unsigned short start, end;

	if (rose->state != ROSE_STATE_3)
		return;

	if (rose->condition & ROSE_COND_PEER_RX_BUSY)
		return;

	if (!skb_peek(&sk->sk_write_queue))
		return;

	start = (skb_peek(&rose->ack_queue) == NULL) ? rose->va : rose->vs;
	end   = (rose->va + sysctl_rose_window_size) % ROSE_MODULUS;

	if (start == end)
		return;

	rose->vs = start;

	/*
	 * Transmit data until either we're out of data to send or
	 * the window is full.
	 */

	skb  = skb_dequeue(&sk->sk_write_queue);

	do {
		if ((skbn = skb_clone(skb, GFP_ATOMIC)) == NULL) {
			skb_queue_head(&sk->sk_write_queue, skb);
			break;
		}

		skb_set_owner_w(skbn, sk);

		/*
		 * Transmit the frame copy.
		 */
		rose_send_iframe(sk, skbn);

		rose->vs = (rose->vs + 1) % ROSE_MODULUS;

		/*
		 * Requeue the original data frame.
		 */
		skb_queue_tail(&rose->ack_queue, skb);

	} while (rose->vs != end &&
		 (skb = skb_dequeue(&sk->sk_write_queue)) != NULL);

	rose->vl         = rose->vr;
	rose->condition &= ~ROSE_COND_ACK_PENDING;

	rose_stop_timer(sk);
}

/*
 * The following routines are taken from page 170 of the 7th ARRL Computer
 * Networking Conference paper, as is the whole state machine.
 */

void rose_enquiry_response(struct sock *sk)
{
	struct rose_sock *rose = rose_sk(sk);

	if (rose->condition & ROSE_COND_OWN_RX_BUSY)
		rose_write_internal(sk, ROSE_RNR);
	else
		rose_write_internal(sk, ROSE_RR);

	rose->vl         = rose->vr;
	rose->condition &= ~ROSE_COND_ACK_PENDING;

	rose_stop_timer(sk);
}
mit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/cgit.cgi/linux/net-next.git/log/?h=nds-private-remove&amp;id=3e03d7ccf4418c87a134bbfa79c05090296767f7'>root</a>/<a href='/cgit.cgi/linux/net-next.git/log/include?h=nds-private-remove&amp;id=3e03d7ccf4418c87a134bbfa79c05090296767f7'>include</a>/<a href='/cgit.cgi/linux/net-next.git/log/include/uapi?h=nds-private-remove&amp;id=3e03d7ccf4418c87a134bbfa79c05090296767f7'>uapi</a>/<a href='/cgit.cgi/linux/net-next.git/log/include/uapi/asm-generic?h=nds-private-remove&amp;id=3e03d7ccf4418c87a134bbfa79c05090296767f7'>asm-generic</a>/<a href='/cgit.cgi/linux/net-next.git/log/include/uapi/asm-generic/ioctl.h?h=nds-private-remove&amp;id=3e03d7ccf4418c87a134bbfa79c05090296767f7'>ioctl.h</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/cgit.cgi/linux/net-next.git/log/include/uapi/asm-generic/ioctl.h?h=nds-private-remove&amp;id=3e03d7ccf4418c87a134bbfa79c05090296767f7&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th><th class='left'>Files</th><th class='left'>Lines</th></tr>
h></tr>
>-0</span>/<span class='insertions'>+106</span></td></tr>
<tr class='nohover-highlight'><td/><td colspan='5' class='logmsg'>
Request Parameter

This patch is to implement Sender-Side Procedures for the Add
Outgoing and Incoming Streams Request Parameter described in
rfc6525 section 5.1.5-5.1.6.

It is also to add sockopt SCTP_ADD_STREAMS in rfc6525 section
6.3.4 for users.

Signed-off-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Acked-by: Marcelo Ricardo Leitner &lt;marcelo.leitner@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;


</td></tr>
<tr class='logheader'><td><span title='2017-02-09 16:57:38 -0500'>2017-02-09</span></td><td class='logsubject'><a href='/cgit.cgi/linux/net-next.git/commit/net/sctp?h=nds-private-remove&amp;id=78098117f8bfad4f2104c3f7b6b69071af95a246'>sctp: add support for generating stream reconf add incoming/outgoing streams ↵</a></td><td>Xin Long</td><td>1</td><td><span class='deletions'>-0</span>/<span class='insertions'>+46</span></td></tr>
<tr class='nohover-highlight'><td/><td colspan='5' class='logmsg'>
request chunk

This patch is to define Add Incoming/Outgoing Streams Request
Parameter described in rfc6525 section 4.5 and 4.6. They can
be in one same chunk trunk as rfc6525 section 3.1-7 describes,
so make them in one function.

Signed-off-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Acked-by: Marcelo Ricardo Leitner &lt;marcelo.leitner@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;


</td></tr>
<tr class='logheader'><td><span title='2017-02-09 16:57:38 -0500'>2017-02-09</span></td><td class='logsubject'><a href='/cgit.cgi/linux/net-next.git/commit/net/sctp?h=nds-private-remove&amp;id=a92ce1a42dde1caaee4afae67531e3e7acecf6e4'>sctp: implement sender-side procedures for SSN/TSN Reset Request Parameter</a></td><td>Xin Long</td><td>2</td><td><span class='deletions'>-0</span>/<span class='insertions'>+69</span></td></tr>
<tr class='nohover-highlight'><td/><td colspan='5' class='logmsg'>
This patch is to implement Sender-Side Procedures for the SSN/TSN
Reset Request Parameter descibed in rfc6525 section 5.1.4.

It is also to add sockopt SCTP_RESET_ASSOC in rfc6525 section 6.3.3
for users.

Signed-off-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Acked-by: Marcelo Ricardo Leitner &lt;marcelo.leitner@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;


</td></tr>
<tr class='logheader'><td><span title='2017-02-09 16:57:38 -0500'>2017-02-09</span></td><td class='logsubject'><a href='/cgit.cgi/linux/net-next.git/commit/net/sctp?h=nds-private-remove&amp;id=c56480a1e90261842f54f3a5a9ebc12d827f0c3e'>sctp: add support for generating stream reconf ssn/tsn reset request chunk</a></td><td>Xin Long</td><td>1</td><td><span class='deletions'>-0</span>/<span class='insertions'>+29</span></td></tr>
<tr class='nohover-highlight'><td/><td colspan='5' class='logmsg'>
This patch is to define SSN/TSN Reset Request Parameter described
in rfc6525 section 4.3.

Signed-off-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;


</td></tr>
<tr class='logheader'><td><span title='2017-02-09 16:57:38 -0500'>2017-02-09</span></td><td class='logsubject'><a href='/cgit.cgi/linux/net-next.git/commit/net/sctp?h=nds-private-remove&amp;id=119aecbae57e6f10b85b7cd5e070eef006dbcd74'>sctp: streams should be recovered when it fails to send request.</a></td><td>Xin Long</td><td>1</td><td><span class='deletions'>-2</span>/<span class='insertions'>+17</span></td></tr>
<tr class='nohover-highlight'><td/><td colspan='5' class='logmsg'>
Now when sending stream reset request, it closes the streams to
block further xmit of data until this request is completed, then
calls sctp_send_reconf to send the chunk.

But if sctp_send_reconf returns err, and it doesn't recover the
streams' states back,  which means the request chunk would not be
queued and sent, so the asoc will get stuck, streams are closed
and no packet is even queued.

This patch is to fix it by recovering the streams' states when
it fails to send the request, it is also to fix a return value.

Fixes: 7f9d68ac944e ("sctp: implement sender-side procedures for SSN Reset Request Parameter")
Signed-off-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Acked-by: Marcelo Ricardo Leitner &lt;marcelo.leitner@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;


</td></tr>
<tr class='logheader'><td><span title='2017-02-07 16:29:30 -0500'>2017-02-07</span></td><td class='logsubject'><a href='/cgit.cgi/linux/net-next.git/commit/net/sctp?h=nds-private-remove&amp;id=3efa70d78f218e4c9276b0bac0545e5184c1c47b'>Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net</a></td><td>David S. Miller