1 files changed, 224 insertions, 0 deletions

diff --git a/net/lapb/lapb_out.c b/net/lapb/lapb_out.c
new file mode 100644
index 000000000000..49a761bd9314
--- /dev/null
+++ b/net/lapb/lapb_out.c
@@ -0,0 +1,224 @@
+/*
+ *      LAPB release 002
+ *
+ *      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
+ *      LAPB 002        Jonathan Naylor New timer architecture.
+ */
+
+#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(struct lapb_cb *lapb, struct sk_buff *skb, int poll_bit)
+{
+        unsigned char *frame;
+
+        if (!skb)
+                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->dev, lapb->state, poll_bit, lapb->vs, lapb->vr);
+#endif
+
+        lapb_transmit_buffer(lapb, skb, LAPB_COMMAND);  
+}
+
+void lapb_kick(struct lapb_cb *lapb)
+{
+        struct sk_buff *skb, *skbn;
+        unsigned short modulus, start, end;
+
+        modulus = (lapb->mode & LAPB_EXTENDED) ? LAPB_EMODULUS : LAPB_SMODULUS;
+        start = !skb_peek(&lapb->ack_queue) ? 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)) {
+                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)
+                                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_running(lapb))
+                        lapb_start_t1timer(lapb);
+        }
+}
+
+void lapb_transmit_buffer(struct 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->dev, lapb->state,
+               skb->data[0], skb->data[1], skb->data[2]);
+#endif
+
+        if (!lapb_data_transmit(lapb, skb))
+                kfree_skb(skb);
+}
+
+void lapb_establish_data_link(struct 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->dev, 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->dev, lapb->state);
+#endif
+                lapb_send_control(lapb, LAPB_SABM, LAPB_POLLON, LAPB_COMMAND);
+        }
+
+        lapb_start_t1timer(lapb);
+        lapb_stop_t2timer(lapb);
+}
+
+void lapb_enquiry_response(struct lapb_cb *lapb)
+{
+#if LAPB_DEBUG > 1
+        printk(KERN_DEBUG "lapb: (%p) S%d TX RR(1) R%d\n",
+               lapb->dev, 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(struct lapb_cb *lapb)
+{
+#if LAPB_DEBUG > 1
+        printk(KERN_DEBUG "lapb: (%p) S%d TX RR(0) R%d\n",
+               lapb->dev, 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(struct lapb_cb *lapb, unsigned short nr)
+{
+        if (lapb->vs == nr) {
+                lapb_frames_acked(lapb, nr);
+                lapb_stop_t1timer(lapb);
+                lapb->n2count = 0;
+        } else if (lapb->va != nr) {
+                lapb_frames_acked(lapb, nr);
+                lapb_start_t1timer(lapb);
+        }
+}
+
+void lapb_check_need_response(struct lapb_cb *lapb, int type, int pf)
+{
+        if (type == LAPB_COMMAND && pf)
+                lapb_enquiry_response(lapb);
+}