Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 226 insertions, 0 deletions

diff --git a/net/x25/x25_out.c b/net/x25/x25_out.c
new file mode 100644
index 000000000000..a2e62cea819a
--- /dev/null
+++ b/net/x25/x25_out.c
@@ -0,0 +1,226 @@
+/*
+ *      X.25 Packet Layer release 002
+ *
+ *      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
+ *
+ *      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
+ *      X.25 001        Jonathan Naylor Started coding.
+ *      X.25 002        Jonathan Naylor New timer architecture.
+ *      2000-09-04      Henner Eisen    Prevented x25_output() skb leakage.
+ *      2000-10-27      Henner Eisen    MSG_DONTWAIT for fragment allocation.
+ *      2000-11-10      Henner Eisen    x25_send_iframe(): re-queued frames
+ *                                      needed cleaned seq-number fields.
+ */
+
+#include <linux/socket.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <net/x25.h>
+
+static int x25_pacsize_to_bytes(unsigned int pacsize)
+{
+        int bytes = 1;
+
+        if (!pacsize)
+                return 128;
+
+        while (pacsize-- > 0)
+                bytes *= 2;
+
+        return bytes;
+}
+
+/*
+ *      This is where all X.25 information frames pass.
+ *
+ *      Returns the amount of user data bytes sent on success
+ *      or a negative error code on failure.
+ */
+int x25_output(struct sock *sk, struct sk_buff *skb)
+{
+        struct sk_buff *skbn;
+        unsigned char header[X25_EXT_MIN_LEN];
+        int err, frontlen, len;
+        int sent=0, noblock = X25_SKB_CB(skb)->flags & MSG_DONTWAIT;
+        struct x25_sock *x25 = x25_sk(sk);
+        int header_len = x25->neighbour->extended ? X25_EXT_MIN_LEN :
+                                                    X25_STD_MIN_LEN;
+        int max_len = x25_pacsize_to_bytes(x25->facilities.pacsize_out);
+
+        if (skb->len - header_len > max_len) {
+                /* Save a copy of the Header */
+                memcpy(header, skb->data, header_len);
+                skb_pull(skb, header_len);
+
+                frontlen = skb_headroom(skb);
+
+                while (skb->len > 0) {
+                        if ((skbn = sock_alloc_send_skb(sk, frontlen + max_len,
+                                                        noblock, &err)) == NULL){
+                                if (err == -EWOULDBLOCK && noblock){
+                                        kfree_skb(skb);
+                                        return sent;
+                                }
+                                SOCK_DEBUG(sk, "x25_output: fragment alloc"
+                                               " failed, err=%d, %d bytes "
+                                               "sent\n", err, sent);
+                                return err;
+                        }
+                                
+                        skb_reserve(skbn, frontlen);
+
+                        len = max_len > skb->len ? skb->len : max_len;
+
+                        /* Copy the user data */
+                        memcpy(skb_put(skbn, len), skb->data, len);
+                        skb_pull(skb, len);
+
+                        /* Duplicate the Header */
+                        skb_push(skbn, header_len);
+                        memcpy(skbn->data, header, header_len);
+
+                        if (skb->len > 0) {
+                                if (x25->neighbour->extended)
+                                        skbn->data[3] |= X25_EXT_M_BIT;
+                                else
+                                        skbn->data[2] |= X25_STD_M_BIT;
+                        }
+
+                        skb_queue_tail(&sk->sk_write_queue, skbn);
+                        sent += len;
+                }
+                
+                kfree_skb(skb);
+        } else {
+                skb_queue_tail(&sk->sk_write_queue, skb);
+                sent = skb->len - header_len;
+        }
+        return sent;
+}
+
+/* 
+ *      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 x25_send_iframe(struct sock *sk, struct sk_buff *skb)
+{
+        struct x25_sock *x25 = x25_sk(sk);
+
+        if (!skb)
+                return;
+
+        if (x25->neighbour->extended) {
+                skb->data[2]  = (x25->vs << 1) & 0xFE;
+                skb->data[3] &= X25_EXT_M_BIT;
+                skb->data[3] |= (x25->vr << 1) & 0xFE;
+        } else {
+                skb->data[2] &= X25_STD_M_BIT;
+                skb->data[2] |= (x25->vs << 1) & 0x0E;
+                skb->data[2] |= (x25->vr << 5) & 0xE0;
+        }
+
+        x25_transmit_link(skb, x25->neighbour); 
+}
+
+void x25_kick(struct sock *sk)
+{
+        struct sk_buff *skb, *skbn;
+        unsigned short start, end;
+        int modulus;
+        struct x25_sock *x25 = x25_sk(sk);
+
+        if (x25->state != X25_STATE_3)
+                return;
+
+        /*
+         *      Transmit interrupt data.
+         */
+        if (!x25->intflag && skb_peek(&x25->interrupt_out_queue) != NULL) {
+                x25->intflag = 1;
+                skb = skb_dequeue(&x25->interrupt_out_queue);
+                x25_transmit_link(skb, x25->neighbour);
+        }
+
+        if (x25->condition & X25_COND_PEER_RX_BUSY)
+                return;
+
+        if (!skb_peek(&sk->sk_write_queue))
+                return;
+
+        modulus = x25->neighbour->extended ? X25_EMODULUS : X25_SMODULUS;
+
+        start   = skb_peek(&x25->ack_queue) ? x25->vs : x25->va;
+        end     = (x25->va + x25->facilities.winsize_out) % modulus;
+
+        if (start == end)
+                return;
+
+        x25->vs = start;
+
+        /*
+         * Transmit data until either we're out of data to send or
+         * the window is full.
+         */
+
+        skb = skb_dequeue(&sk->sk_write_queue);
+
+        do {
+                if ((skbn = skb_clone(skb, GFP_ATOMIC)) == NULL) {
+                        skb_queue_head(&sk->sk_write_queue, skb);
+                        break;
+                }
+
+                skb_set_owner_w(skbn, sk);
+
+                /*
+                 * Transmit the frame copy.
+                 */
+                x25_send_iframe(sk, skbn);
+
+                x25->vs = (x25->vs + 1) % modulus;
+
+                /*
+                 * Requeue the original data frame.
+                 */
+                skb_queue_tail(&x25->ack_queue, skb);
+
+        } while (x25->vs != end &&
+                 (skb = skb_dequeue(&sk->sk_write_queue)) != NULL);
+
+        x25->vl         = x25->vr;
+        x25->condition &= ~X25_COND_ACK_PENDING;
+
+        x25_stop_timer(sk);
+}
+
+/*
+ * The following routines are taken from page 170 of the 7th ARRL Computer
+ * Networking Conference paper, as is the whole state machine.
+ */
+
+void x25_enquiry_response(struct sock *sk)
+{
+        struct x25_sock *x25 = x25_sk(sk);
+
+        if (x25->condition & X25_COND_OWN_RX_BUSY)
+                x25_write_internal(sk, X25_RNR);
+        else
+                x25_write_internal(sk, X25_RR);
+
+        x25->vl         = x25->vr;
+        x25->condition &= ~X25_COND_ACK_PENDING;
+
+        x25_stop_timer(sk);
+}