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