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authorRalf Baechle <ralf@linux-mips.org>1997-04-29 21:13:14 +0000
committer <ralf@linux-mips.org>1997-04-29 21:13:14 +0000
commit19c9bba94152148523ba0f7ef7cffe3d45656b11 (patch)
tree40b1cb534496a7f1ca0f5c314a523c69f1fee464 /net/lapb/lapb_out.c
parent7206675c40394c78a90e74812bbdbf8cf3cca1be (diff)
Import of Linux/MIPS 2.1.36
Diffstat (limited to 'net/lapb/lapb_out.c')
-rw-r--r--net/lapb/lapb_out.c233
1 files changed, 233 insertions, 0 deletions
diff --git a/net/lapb/lapb_out.c b/net/lapb/lapb_out.c
new file mode 100644
index 000000000..1256e3a3c
--- /dev/null
+++ b/net/lapb/lapb_out.c
@@ -0,0 +1,233 @@
+/*
+ * LAPB release 001
+ *
+ * This is ALPHA test software. This code may break your machine, randomly fail to work with new
+ * releases, misbehave and/or generally screw up. It might even work.
+ *
+ * This code REQUIRES 2.1.15 or higher/ NET3.038
+ *
+ * This module:
+ * This module 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.
+ *
+ * History
+ * LAPB 001 Jonathan Naylor Started Coding
+ */
+
+#include <linux/config.h>
+#if defined(CONFIG_LAPB) || defined(CONFIG_LAPB_MODULE)
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/in.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/timer.h>
+#include <linux/string.h>
+#include <linux/sockios.h>
+#include <linux/net.h>
+#include <linux/inet.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <linux/fcntl.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <net/lapb.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 lapb_send_iframe(lapb_cb *lapb, struct sk_buff *skb, int poll_bit)
+{
+ unsigned char *frame;
+
+ if (skb == NULL)
+ return;
+
+ if (lapb->mode & LAPB_EXTENDED) {
+ frame = skb_push(skb, 2);
+
+ frame[0] = LAPB_I;
+ frame[0] |= (lapb->vs << 1);
+ frame[1] = (poll_bit) ? LAPB_EPF : 0;
+ frame[1] |= (lapb->vr << 1);
+ } else {
+ frame = skb_push(skb, 1);
+
+ *frame = LAPB_I;
+ *frame |= (poll_bit) ? LAPB_SPF : 0;
+ *frame |= (lapb->vr << 5);
+ *frame |= (lapb->vs << 1);
+ }
+
+#if LAPB_DEBUG > 1
+ printk(KERN_DEBUG "lapb: (%p) S%d TX I(%d) S%d R%d\n", lapb->token, lapb->state, poll_bit, lapb->vs, lapb->vr);
+#endif
+
+ lapb_transmit_buffer(lapb, skb, LAPB_COMMAND);
+}
+
+void lapb_kick(lapb_cb *lapb)
+{
+ struct sk_buff *skb, *skbn;
+ unsigned short modulus, start, end;
+
+ del_timer(&lapb->timer);
+
+ modulus = (lapb->mode & LAPB_EXTENDED) ? LAPB_EMODULUS : LAPB_SMODULUS;
+
+ start = (skb_peek(&lapb->ack_queue) == NULL) ? lapb->va : lapb->vs;
+ end = (lapb->va + lapb->window) % modulus;
+
+ if (!(lapb->condition & LAPB_PEER_RX_BUSY_CONDITION) &&
+ start != end &&
+ skb_peek(&lapb->write_queue) != NULL) {
+
+ lapb->vs = start;
+
+ /*
+ * Dequeue the frame and copy it.
+ */
+ skb = skb_dequeue(&lapb->write_queue);
+
+ do {
+ if ((skbn = skb_clone(skb, GFP_ATOMIC)) == NULL) {
+ skb_queue_head(&lapb->write_queue, skb);
+ break;
+ }
+
+ if (skb->sk != NULL)
+ skb_set_owner_w(skbn, skb->sk);
+
+ /*
+ * Transmit the frame copy.
+ */
+ lapb_send_iframe(lapb, skbn, LAPB_POLLOFF);
+
+ lapb->vs = (lapb->vs + 1) % modulus;
+
+ /*
+ * Requeue the original data frame.
+ */
+ skb_queue_tail(&lapb->ack_queue, skb);
+
+ } while (lapb->vs != end && (skb = skb_dequeue(&lapb->write_queue)) != NULL);
+
+ lapb->condition &= ~LAPB_ACK_PENDING_CONDITION;
+
+ if (lapb->t1timer == 0)
+ lapb->t1timer = lapb->t1;
+ }
+
+ lapb_set_timer(lapb);
+}
+
+void lapb_transmit_buffer(lapb_cb *lapb, struct sk_buff *skb, int type)
+{
+ unsigned char *ptr;
+
+ ptr = skb_push(skb, 1);
+
+ if (lapb->mode & LAPB_MLP) {
+ if (lapb->mode & LAPB_DCE) {
+ if (type == LAPB_COMMAND)
+ *ptr = LAPB_ADDR_C;
+ if (type == LAPB_RESPONSE)
+ *ptr = LAPB_ADDR_D;
+ } else {
+ if (type == LAPB_COMMAND)
+ *ptr = LAPB_ADDR_D;
+ if (type == LAPB_RESPONSE)
+ *ptr = LAPB_ADDR_C;
+ }
+ } else {
+ if (lapb->mode & LAPB_DCE) {
+ if (type == LAPB_COMMAND)
+ *ptr = LAPB_ADDR_A;
+ if (type == LAPB_RESPONSE)
+ *ptr = LAPB_ADDR_B;
+ } else {
+ if (type == LAPB_COMMAND)
+ *ptr = LAPB_ADDR_B;
+ if (type == LAPB_RESPONSE)
+ *ptr = LAPB_ADDR_A;
+ }
+ }
+
+#if LAPB_DEBUG > 2
+ printk(KERN_DEBUG "lapb: (%p) S%d TX %02X %02X %02X\n", lapb->token, lapb->state, skb->data[0], skb->data[1], skb->data[2]);
+#endif
+
+ if (!lapb_data_transmit(lapb, skb))
+ kfree_skb(skb, FREE_WRITE);
+}
+
+void lapb_establish_data_link(lapb_cb *lapb)
+{
+ lapb->condition = 0x00;
+ lapb->n2count = 0;
+
+ if (lapb->mode & LAPB_EXTENDED) {
+#if LAPB_DEBUG > 1
+ printk(KERN_DEBUG "lapb: (%p) S%d TX SABME(1)\n", lapb->token, lapb->state);
+#endif
+ lapb_send_control(lapb, LAPB_SABME, LAPB_POLLON, LAPB_COMMAND);
+ } else {
+#if LAPB_DEBUG > 1
+ printk(KERN_DEBUG "lapb: (%p) S%d TX SABM(1)\n", lapb->token, lapb->state);
+#endif
+ lapb_send_control(lapb, LAPB_SABM, LAPB_POLLON, LAPB_COMMAND);
+ }
+
+ lapb->t2timer = 0;
+ lapb->t1timer = lapb->t1;
+}
+
+void lapb_enquiry_response(lapb_cb *lapb)
+{
+#if LAPB_DEBUG > 1
+ printk(KERN_DEBUG "lapb: (%p) S%d TX RR(1) R%d\n", lapb->token, lapb->state, lapb->vr);
+#endif
+
+ lapb_send_control(lapb, LAPB_RR, LAPB_POLLON, LAPB_RESPONSE);
+
+ lapb->condition &= ~LAPB_ACK_PENDING_CONDITION;
+}
+
+void lapb_timeout_response(lapb_cb *lapb)
+{
+#if LAPB_DEBUG > 1
+ printk(KERN_DEBUG "lapb: (%p) S%d TX RR(0) R%d\n", lapb->token, lapb->state, lapb->vr);
+#endif
+
+ lapb_send_control(lapb, LAPB_RR, LAPB_POLLOFF, LAPB_RESPONSE);
+
+ lapb->condition &= ~LAPB_ACK_PENDING_CONDITION;
+}
+
+void lapb_check_iframes_acked(lapb_cb *lapb, unsigned short nr)
+{
+ if (lapb->vs == nr) {
+ lapb_frames_acked(lapb, nr);
+ lapb->t1timer = 0;
+ lapb->n2count = 0;
+ } else {
+ if (lapb->va != nr) {
+ lapb_frames_acked(lapb, nr);
+ lapb->t1timer = lapb->t1;
+ }
+ }
+}
+
+void lapb_check_need_response(lapb_cb *lapb, int type, int pf)
+{
+ if (type == LAPB_COMMAND && pf)
+ lapb_enquiry_response(lapb);
+}
+
+#endif