[SCSI] dc395x: atomic_kmap for PIO
[firewire-audio.git] / net / netrom / nr_in.c
blob64b81a7969077c706353e76309a67698380f2095
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.
7 * Copyright Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
8 * Copyright Darryl Miles G7LED (dlm@g7led.demon.co.uk)
9 */
10 #include <linux/errno.h>
11 #include <linux/types.h>
12 #include <linux/socket.h>
13 #include <linux/in.h>
14 #include <linux/kernel.h>
15 #include <linux/sched.h>
16 #include <linux/timer.h>
17 #include <linux/string.h>
18 #include <linux/sockios.h>
19 #include <linux/net.h>
20 #include <net/ax25.h>
21 #include <linux/inet.h>
22 #include <linux/netdevice.h>
23 #include <linux/skbuff.h>
24 #include <net/sock.h>
25 #include <net/tcp_states.h>
26 #include <asm/uaccess.h>
27 #include <asm/system.h>
28 #include <linux/fcntl.h>
29 #include <linux/mm.h>
30 #include <linux/interrupt.h>
31 #include <net/netrom.h>
33 static int nr_queue_rx_frame(struct sock *sk, struct sk_buff *skb, int more)
35 struct sk_buff *skbo, *skbn = skb;
36 struct nr_sock *nr = nr_sk(sk);
38 skb_pull(skb, NR_NETWORK_LEN + NR_TRANSPORT_LEN);
40 nr_start_idletimer(sk);
42 if (more) {
43 nr->fraglen += skb->len;
44 skb_queue_tail(&nr->frag_queue, skb);
45 return 0;
48 if (!more && nr->fraglen > 0) { /* End of fragment */
49 nr->fraglen += skb->len;
50 skb_queue_tail(&nr->frag_queue, skb);
52 if ((skbn = alloc_skb(nr->fraglen, GFP_ATOMIC)) == NULL)
53 return 1;
55 skbn->h.raw = skbn->data;
57 while ((skbo = skb_dequeue(&nr->frag_queue)) != NULL) {
58 memcpy(skb_put(skbn, skbo->len), skbo->data, skbo->len);
59 kfree_skb(skbo);
62 nr->fraglen = 0;
65 return sock_queue_rcv_skb(sk, skbn);
69 * State machine for state 1, Awaiting Connection State.
70 * The handling of the timer(s) is in file nr_timer.c.
71 * Handling of state 0 and connection release is in netrom.c.
73 static int nr_state1_machine(struct sock *sk, struct sk_buff *skb,
74 int frametype)
76 switch (frametype) {
77 case NR_CONNACK: {
78 struct nr_sock *nr = nr_sk(sk);
80 nr_stop_t1timer(sk);
81 nr_start_idletimer(sk);
82 nr->your_index = skb->data[17];
83 nr->your_id = skb->data[18];
84 nr->vs = 0;
85 nr->va = 0;
86 nr->vr = 0;
87 nr->vl = 0;
88 nr->state = NR_STATE_3;
89 nr->n2count = 0;
90 nr->window = skb->data[20];
91 sk->sk_state = TCP_ESTABLISHED;
92 if (!sock_flag(sk, SOCK_DEAD))
93 sk->sk_state_change(sk);
94 break;
97 case NR_CONNACK | NR_CHOKE_FLAG:
98 nr_disconnect(sk, ECONNREFUSED);
99 break;
101 default:
102 break;
104 return 0;
108 * State machine for state 2, Awaiting Release State.
109 * The handling of the timer(s) is in file nr_timer.c
110 * Handling of state 0 and connection release is in netrom.c.
112 static int nr_state2_machine(struct sock *sk, struct sk_buff *skb,
113 int frametype)
115 switch (frametype) {
116 case NR_CONNACK | NR_CHOKE_FLAG:
117 nr_disconnect(sk, ECONNRESET);
118 break;
120 case NR_DISCREQ:
121 nr_write_internal(sk, NR_DISCACK);
123 case NR_DISCACK:
124 nr_disconnect(sk, 0);
125 break;
127 default:
128 break;
130 return 0;
134 * State machine for state 3, Connected State.
135 * The handling of the timer(s) is in file nr_timer.c
136 * Handling of state 0 and connection release is in netrom.c.
138 static int nr_state3_machine(struct sock *sk, struct sk_buff *skb, int frametype)
140 struct nr_sock *nrom = nr_sk(sk);
141 struct sk_buff_head temp_queue;
142 struct sk_buff *skbn;
143 unsigned short save_vr;
144 unsigned short nr, ns;
145 int queued = 0;
147 nr = skb->data[18];
148 ns = skb->data[17];
150 switch (frametype) {
151 case NR_CONNREQ:
152 nr_write_internal(sk, NR_CONNACK);
153 break;
155 case NR_DISCREQ:
156 nr_write_internal(sk, NR_DISCACK);
157 nr_disconnect(sk, 0);
158 break;
160 case NR_CONNACK | NR_CHOKE_FLAG:
161 case NR_DISCACK:
162 nr_disconnect(sk, ECONNRESET);
163 break;
165 case NR_INFOACK:
166 case NR_INFOACK | NR_CHOKE_FLAG:
167 case NR_INFOACK | NR_NAK_FLAG:
168 case NR_INFOACK | NR_NAK_FLAG | NR_CHOKE_FLAG:
169 if (frametype & NR_CHOKE_FLAG) {
170 nrom->condition |= NR_COND_PEER_RX_BUSY;
171 nr_start_t4timer(sk);
172 } else {
173 nrom->condition &= ~NR_COND_PEER_RX_BUSY;
174 nr_stop_t4timer(sk);
176 if (!nr_validate_nr(sk, nr)) {
177 break;
179 if (frametype & NR_NAK_FLAG) {
180 nr_frames_acked(sk, nr);
181 nr_send_nak_frame(sk);
182 } else {
183 if (nrom->condition & NR_COND_PEER_RX_BUSY) {
184 nr_frames_acked(sk, nr);
185 } else {
186 nr_check_iframes_acked(sk, nr);
189 break;
191 case NR_INFO:
192 case NR_INFO | NR_NAK_FLAG:
193 case NR_INFO | NR_CHOKE_FLAG:
194 case NR_INFO | NR_MORE_FLAG:
195 case NR_INFO | NR_NAK_FLAG | NR_CHOKE_FLAG:
196 case NR_INFO | NR_CHOKE_FLAG | NR_MORE_FLAG:
197 case NR_INFO | NR_NAK_FLAG | NR_MORE_FLAG:
198 case NR_INFO | NR_NAK_FLAG | NR_CHOKE_FLAG | NR_MORE_FLAG:
199 if (frametype & NR_CHOKE_FLAG) {
200 nrom->condition |= NR_COND_PEER_RX_BUSY;
201 nr_start_t4timer(sk);
202 } else {
203 nrom->condition &= ~NR_COND_PEER_RX_BUSY;
204 nr_stop_t4timer(sk);
206 if (nr_validate_nr(sk, nr)) {
207 if (frametype & NR_NAK_FLAG) {
208 nr_frames_acked(sk, nr);
209 nr_send_nak_frame(sk);
210 } else {
211 if (nrom->condition & NR_COND_PEER_RX_BUSY) {
212 nr_frames_acked(sk, nr);
213 } else {
214 nr_check_iframes_acked(sk, nr);
218 queued = 1;
219 skb_queue_head(&nrom->reseq_queue, skb);
220 if (nrom->condition & NR_COND_OWN_RX_BUSY)
221 break;
222 skb_queue_head_init(&temp_queue);
223 do {
224 save_vr = nrom->vr;
225 while ((skbn = skb_dequeue(&nrom->reseq_queue)) != NULL) {
226 ns = skbn->data[17];
227 if (ns == nrom->vr) {
228 if (nr_queue_rx_frame(sk, skbn, frametype & NR_MORE_FLAG) == 0) {
229 nrom->vr = (nrom->vr + 1) % NR_MODULUS;
230 } else {
231 nrom->condition |= NR_COND_OWN_RX_BUSY;
232 skb_queue_tail(&temp_queue, skbn);
234 } else if (nr_in_rx_window(sk, ns)) {
235 skb_queue_tail(&temp_queue, skbn);
236 } else {
237 kfree_skb(skbn);
240 while ((skbn = skb_dequeue(&temp_queue)) != NULL) {
241 skb_queue_tail(&nrom->reseq_queue, skbn);
243 } while (save_vr != nrom->vr);
245 * Window is full, ack it immediately.
247 if (((nrom->vl + nrom->window) % NR_MODULUS) == nrom->vr) {
248 nr_enquiry_response(sk);
249 } else {
250 if (!(nrom->condition & NR_COND_ACK_PENDING)) {
251 nrom->condition |= NR_COND_ACK_PENDING;
252 nr_start_t2timer(sk);
255 break;
257 default:
258 break;
260 return queued;
263 /* Higher level upcall for a LAPB frame - called with sk locked */
264 int nr_process_rx_frame(struct sock *sk, struct sk_buff *skb)
266 struct nr_sock *nr = nr_sk(sk);
267 int queued = 0, frametype;
269 if (nr->state == NR_STATE_0)
270 return 0;
272 frametype = skb->data[19];
274 switch (nr->state) {
275 case NR_STATE_1:
276 queued = nr_state1_machine(sk, skb, frametype);
277 break;
278 case NR_STATE_2:
279 queued = nr_state2_machine(sk, skb, frametype);
280 break;
281 case NR_STATE_3:
282 queued = nr_state3_machine(sk, skb, frametype);
283 break;
286 nr_kick(sk);
288 return queued;