1 // SPDX-License-Identifier: GPL-2.0-or-later <<
2 /* 1 /*
>> 2 * This program is free software; you can redistribute it and/or modify
>> 3 * it under the terms of the GNU General Public License as published by
>> 4 * the Free Software Foundation; either version 2 of the License, or
>> 5 * (at your option) any later version.
3 * 6 *
4 * Copyright (C) Jonathan Naylor G4KLX (g4klx@ 7 * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
5 */ 8 */
6 #include <linux/errno.h> 9 #include <linux/errno.h>
7 #include <linux/types.h> 10 #include <linux/types.h>
8 #include <linux/socket.h> 11 #include <linux/socket.h>
9 #include <linux/in.h> 12 #include <linux/in.h>
10 #include <linux/kernel.h> 13 #include <linux/kernel.h>
11 #include <linux/timer.h> 14 #include <linux/timer.h>
12 #include <linux/string.h> 15 #include <linux/string.h>
13 #include <linux/sockios.h> 16 #include <linux/sockios.h>
14 #include <linux/net.h> 17 #include <linux/net.h>
15 #include <linux/gfp.h> 18 #include <linux/gfp.h>
16 #include <net/ax25.h> 19 #include <net/ax25.h>
17 #include <linux/inet.h> 20 #include <linux/inet.h>
18 #include <linux/netdevice.h> 21 #include <linux/netdevice.h>
19 #include <linux/skbuff.h> 22 #include <linux/skbuff.h>
20 #include <net/sock.h> 23 #include <net/sock.h>
21 #include <linux/fcntl.h> 24 #include <linux/fcntl.h>
22 #include <linux/mm.h> 25 #include <linux/mm.h>
23 #include <linux/interrupt.h> 26 #include <linux/interrupt.h>
24 #include <net/rose.h> 27 #include <net/rose.h>
25 28
26 /* 29 /*
27 * This procedure is passed a buffer desc 30 * This procedure is passed a buffer descriptor for an iframe. It builds
28 * the rest of the control part of the fr 31 * the rest of the control part of the frame and then writes it out.
29 */ 32 */
30 static void rose_send_iframe(struct sock *sk, 33 static void rose_send_iframe(struct sock *sk, struct sk_buff *skb)
31 { 34 {
32 struct rose_sock *rose = rose_sk(sk); 35 struct rose_sock *rose = rose_sk(sk);
33 36
34 if (skb == NULL) 37 if (skb == NULL)
35 return; 38 return;
36 39
37 skb->data[2] |= (rose->vr << 5) & 0xE0 40 skb->data[2] |= (rose->vr << 5) & 0xE0;
38 skb->data[2] |= (rose->vs << 1) & 0x0E 41 skb->data[2] |= (rose->vs << 1) & 0x0E;
39 42
40 rose_start_idletimer(sk); 43 rose_start_idletimer(sk);
41 44
42 rose_transmit_link(skb, rose->neighbou 45 rose_transmit_link(skb, rose->neighbour);
43 } 46 }
44 47
45 void rose_kick(struct sock *sk) 48 void rose_kick(struct sock *sk)
46 { 49 {
47 struct rose_sock *rose = rose_sk(sk); 50 struct rose_sock *rose = rose_sk(sk);
48 struct sk_buff *skb, *skbn; 51 struct sk_buff *skb, *skbn;
49 unsigned short start, end; 52 unsigned short start, end;
50 53
51 if (rose->state != ROSE_STATE_3) 54 if (rose->state != ROSE_STATE_3)
52 return; 55 return;
53 56
54 if (rose->condition & ROSE_COND_PEER_R 57 if (rose->condition & ROSE_COND_PEER_RX_BUSY)
55 return; 58 return;
56 59
57 if (!skb_peek(&sk->sk_write_queue)) 60 if (!skb_peek(&sk->sk_write_queue))
58 return; 61 return;
59 62
60 start = (skb_peek(&rose->ack_queue) == 63 start = (skb_peek(&rose->ack_queue) == NULL) ? rose->va : rose->vs;
61 end = (rose->va + sysctl_rose_window 64 end = (rose->va + sysctl_rose_window_size) % ROSE_MODULUS;
62 65
63 if (start == end) 66 if (start == end)
64 return; 67 return;
65 68
66 rose->vs = start; 69 rose->vs = start;
67 70
68 /* 71 /*
69 * Transmit data until either we're ou 72 * Transmit data until either we're out of data to send or
70 * the window is full. 73 * the window is full.
71 */ 74 */
72 75
73 skb = skb_dequeue(&sk->sk_write_queue 76 skb = skb_dequeue(&sk->sk_write_queue);
74 77
75 do { 78 do {
76 if ((skbn = skb_clone(skb, GFP 79 if ((skbn = skb_clone(skb, GFP_ATOMIC)) == NULL) {
77 skb_queue_head(&sk->sk 80 skb_queue_head(&sk->sk_write_queue, skb);
78 break; 81 break;
79 } 82 }
80 83
81 skb_set_owner_w(skbn, sk); 84 skb_set_owner_w(skbn, sk);
82 85
83 /* 86 /*
84 * Transmit the frame copy. 87 * Transmit the frame copy.
85 */ 88 */
86 rose_send_iframe(sk, skbn); 89 rose_send_iframe(sk, skbn);
87 90
88 rose->vs = (rose->vs + 1) % RO 91 rose->vs = (rose->vs + 1) % ROSE_MODULUS;
89 92
90 /* 93 /*
91 * Requeue the original data f 94 * Requeue the original data frame.
92 */ 95 */
93 skb_queue_tail(&rose->ack_queu 96 skb_queue_tail(&rose->ack_queue, skb);
94 97
95 } while (rose->vs != end && 98 } while (rose->vs != end &&
96 (skb = skb_dequeue(&sk->sk_wr 99 (skb = skb_dequeue(&sk->sk_write_queue)) != NULL);
97 100
98 rose->vl = rose->vr; 101 rose->vl = rose->vr;
99 rose->condition &= ~ROSE_COND_ACK_PEND 102 rose->condition &= ~ROSE_COND_ACK_PENDING;
100 103
101 rose_stop_timer(sk); 104 rose_stop_timer(sk);
102 } 105 }
103 106
104 /* 107 /*
105 * The following routines are taken from page 108 * The following routines are taken from page 170 of the 7th ARRL Computer
106 * Networking Conference paper, as is the whol 109 * Networking Conference paper, as is the whole state machine.
107 */ 110 */
108 111
109 void rose_enquiry_response(struct sock *sk) 112 void rose_enquiry_response(struct sock *sk)
110 { 113 {
111 struct rose_sock *rose = rose_sk(sk); 114 struct rose_sock *rose = rose_sk(sk);
112 115
113 if (rose->condition & ROSE_COND_OWN_RX 116 if (rose->condition & ROSE_COND_OWN_RX_BUSY)
114 rose_write_internal(sk, ROSE_R 117 rose_write_internal(sk, ROSE_RNR);
115 else 118 else
116 rose_write_internal(sk, ROSE_R 119 rose_write_internal(sk, ROSE_RR);
117 120
118 rose->vl = rose->vr; 121 rose->vl = rose->vr;
119 rose->condition &= ~ROSE_COND_ACK_PEND 122 rose->condition &= ~ROSE_COND_ACK_PENDING;
120 123
121 rose_stop_timer(sk); 124 rose_stop_timer(sk);
122 } 125 }
123 126
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.