alistair23-linux/net/lapb/lapb_subr.c
Tim Schmielau cd354f1ae7 [PATCH] remove many unneeded #includes of sched.h
After Al Viro (finally) succeeded in removing the sched.h #include in module.h
recently, it makes sense again to remove other superfluous sched.h includes.
There are quite a lot of files which include it but don't actually need
anything defined in there.  Presumably these includes were once needed for
macros that used to live in sched.h, but moved to other header files in the
course of cleaning it up.

To ease the pain, this time I did not fiddle with any header files and only
removed #includes from .c-files, which tend to cause less trouble.

Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha,
arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig,
allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all
configs in arch/arm/configs on arm.  I also checked that no new warnings were
introduced by the patch (actually, some warnings are removed that were emitted
by unnecessarily included header files).

Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-14 08:09:54 -08:00

313 lines
7.8 KiB
C

/*
* 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
*/
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/kernel.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 routine purges all the queues of frames.
*/
void lapb_clear_queues(struct lapb_cb *lapb)
{
skb_queue_purge(&lapb->write_queue);
skb_queue_purge(&lapb->ack_queue);
}
/*
* This routine purges the input queue of those frames that have been
* acknowledged. This replaces the boxes labelled "V(a) <- N(r)" on the
* SDL diagram.
*/
void lapb_frames_acked(struct lapb_cb *lapb, unsigned short nr)
{
struct sk_buff *skb;
int modulus;
modulus = (lapb->mode & LAPB_EXTENDED) ? LAPB_EMODULUS : LAPB_SMODULUS;
/*
* Remove all the ack-ed frames from the ack queue.
*/
if (lapb->va != nr)
while (skb_peek(&lapb->ack_queue) && lapb->va != nr) {
skb = skb_dequeue(&lapb->ack_queue);
kfree_skb(skb);
lapb->va = (lapb->va + 1) % modulus;
}
}
void lapb_requeue_frames(struct lapb_cb *lapb)
{
struct sk_buff *skb, *skb_prev = NULL;
/*
* Requeue all the un-ack-ed frames on the output queue to be picked
* up by lapb_kick called from the timer. This arrangement handles the
* possibility of an empty output queue.
*/
while ((skb = skb_dequeue(&lapb->ack_queue)) != NULL) {
if (!skb_prev)
skb_queue_head(&lapb->write_queue, skb);
else
skb_append(skb_prev, skb, &lapb->write_queue);
skb_prev = skb;
}
}
/*
* Validate that the value of nr is between va and vs. Return true or
* false for testing.
*/
int lapb_validate_nr(struct lapb_cb *lapb, unsigned short nr)
{
unsigned short vc = lapb->va;
int modulus;
modulus = (lapb->mode & LAPB_EXTENDED) ? LAPB_EMODULUS : LAPB_SMODULUS;
while (vc != lapb->vs) {
if (nr == vc)
return 1;
vc = (vc + 1) % modulus;
}
return nr == lapb->vs;
}
/*
* This routine is the centralised routine for parsing the control
* information for the different frame formats.
*/
int lapb_decode(struct lapb_cb *lapb, struct sk_buff *skb,
struct lapb_frame *frame)
{
frame->type = LAPB_ILLEGAL;
#if LAPB_DEBUG > 2
printk(KERN_DEBUG "lapb: (%p) S%d RX %02X %02X %02X\n",
lapb->dev, lapb->state,
skb->data[0], skb->data[1], skb->data[2]);
#endif
/* We always need to look at 2 bytes, sometimes we need
* to look at 3 and those cases are handled below.
*/
if (!pskb_may_pull(skb, 2))
return -1;
if (lapb->mode & LAPB_MLP) {
if (lapb->mode & LAPB_DCE) {
if (skb->data[0] == LAPB_ADDR_D)
frame->cr = LAPB_COMMAND;
if (skb->data[0] == LAPB_ADDR_C)
frame->cr = LAPB_RESPONSE;
} else {
if (skb->data[0] == LAPB_ADDR_C)
frame->cr = LAPB_COMMAND;
if (skb->data[0] == LAPB_ADDR_D)
frame->cr = LAPB_RESPONSE;
}
} else {
if (lapb->mode & LAPB_DCE) {
if (skb->data[0] == LAPB_ADDR_B)
frame->cr = LAPB_COMMAND;
if (skb->data[0] == LAPB_ADDR_A)
frame->cr = LAPB_RESPONSE;
} else {
if (skb->data[0] == LAPB_ADDR_A)
frame->cr = LAPB_COMMAND;
if (skb->data[0] == LAPB_ADDR_B)
frame->cr = LAPB_RESPONSE;
}
}
skb_pull(skb, 1);
if (lapb->mode & LAPB_EXTENDED) {
if (!(skb->data[0] & LAPB_S)) {
if (!pskb_may_pull(skb, 2))
return -1;
/*
* I frame - carries NR/NS/PF
*/
frame->type = LAPB_I;
frame->ns = (skb->data[0] >> 1) & 0x7F;
frame->nr = (skb->data[1] >> 1) & 0x7F;
frame->pf = skb->data[1] & LAPB_EPF;
frame->control[0] = skb->data[0];
frame->control[1] = skb->data[1];
skb_pull(skb, 2);
} else if ((skb->data[0] & LAPB_U) == 1) {
if (!pskb_may_pull(skb, 2))
return -1;
/*
* S frame - take out PF/NR
*/
frame->type = skb->data[0] & 0x0F;
frame->nr = (skb->data[1] >> 1) & 0x7F;
frame->pf = skb->data[1] & LAPB_EPF;
frame->control[0] = skb->data[0];
frame->control[1] = skb->data[1];
skb_pull(skb, 2);
} else if ((skb->data[0] & LAPB_U) == 3) {
/*
* U frame - take out PF
*/
frame->type = skb->data[0] & ~LAPB_SPF;
frame->pf = skb->data[0] & LAPB_SPF;
frame->control[0] = skb->data[0];
frame->control[1] = 0x00;
skb_pull(skb, 1);
}
} else {
if (!(skb->data[0] & LAPB_S)) {
/*
* I frame - carries NR/NS/PF
*/
frame->type = LAPB_I;
frame->ns = (skb->data[0] >> 1) & 0x07;
frame->nr = (skb->data[0] >> 5) & 0x07;
frame->pf = skb->data[0] & LAPB_SPF;
} else if ((skb->data[0] & LAPB_U) == 1) {
/*
* S frame - take out PF/NR
*/
frame->type = skb->data[0] & 0x0F;
frame->nr = (skb->data[0] >> 5) & 0x07;
frame->pf = skb->data[0] & LAPB_SPF;
} else if ((skb->data[0] & LAPB_U) == 3) {
/*
* U frame - take out PF
*/
frame->type = skb->data[0] & ~LAPB_SPF;
frame->pf = skb->data[0] & LAPB_SPF;
}
frame->control[0] = skb->data[0];
skb_pull(skb, 1);
}
return 0;
}
/*
* This routine is called when the HDLC layer internally generates a
* command or response for the remote machine ( eg. RR, UA etc. ).
* Only supervisory or unnumbered frames are processed, FRMRs are handled
* by lapb_transmit_frmr below.
*/
void lapb_send_control(struct lapb_cb *lapb, int frametype,
int poll_bit, int type)
{
struct sk_buff *skb;
unsigned char *dptr;
if ((skb = alloc_skb(LAPB_HEADER_LEN + 3, GFP_ATOMIC)) == NULL)
return;
skb_reserve(skb, LAPB_HEADER_LEN + 1);
if (lapb->mode & LAPB_EXTENDED) {
if ((frametype & LAPB_U) == LAPB_U) {
dptr = skb_put(skb, 1);
*dptr = frametype;
*dptr |= poll_bit ? LAPB_SPF : 0;
} else {
dptr = skb_put(skb, 2);
dptr[0] = frametype;
dptr[1] = (lapb->vr << 1);
dptr[1] |= poll_bit ? LAPB_EPF : 0;
}
} else {
dptr = skb_put(skb, 1);
*dptr = frametype;
*dptr |= poll_bit ? LAPB_SPF : 0;
if ((frametype & LAPB_U) == LAPB_S) /* S frames carry NR */
*dptr |= (lapb->vr << 5);
}
lapb_transmit_buffer(lapb, skb, type);
}
/*
* This routine generates FRMRs based on information previously stored in
* the LAPB control block.
*/
void lapb_transmit_frmr(struct lapb_cb *lapb)
{
struct sk_buff *skb;
unsigned char *dptr;
if ((skb = alloc_skb(LAPB_HEADER_LEN + 7, GFP_ATOMIC)) == NULL)
return;
skb_reserve(skb, LAPB_HEADER_LEN + 1);
if (lapb->mode & LAPB_EXTENDED) {
dptr = skb_put(skb, 6);
*dptr++ = LAPB_FRMR;
*dptr++ = lapb->frmr_data.control[0];
*dptr++ = lapb->frmr_data.control[1];
*dptr++ = (lapb->vs << 1) & 0xFE;
*dptr = (lapb->vr << 1) & 0xFE;
if (lapb->frmr_data.cr == LAPB_RESPONSE)
*dptr |= 0x01;
dptr++;
*dptr++ = lapb->frmr_type;
#if LAPB_DEBUG > 1
printk(KERN_DEBUG "lapb: (%p) S%d TX FRMR %02X %02X %02X %02X %02X\n",
lapb->dev, lapb->state,
skb->data[1], skb->data[2], skb->data[3],
skb->data[4], skb->data[5]);
#endif
} else {
dptr = skb_put(skb, 4);
*dptr++ = LAPB_FRMR;
*dptr++ = lapb->frmr_data.control[0];
*dptr = (lapb->vs << 1) & 0x0E;
*dptr |= (lapb->vr << 5) & 0xE0;
if (lapb->frmr_data.cr == LAPB_RESPONSE)
*dptr |= 0x10;
dptr++;
*dptr++ = lapb->frmr_type;
#if LAPB_DEBUG > 1
printk(KERN_DEBUG "lapb: (%p) S%d TX FRMR %02X %02X %02X\n",
lapb->dev, lapb->state, skb->data[1],
skb->data[2], skb->data[3]);
#endif
}
lapb_transmit_buffer(lapb, skb, LAPB_RESPONSE);
}