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1442 lines
33 KiB
1442 lines
33 KiB
// SPDX-License-Identifier: GPL-2.0-only |
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/* |
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* slip.c This module implements the SLIP protocol for kernel-based |
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* devices like TTY. It interfaces between a raw TTY, and the |
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* kernel's INET protocol layers. |
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* |
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* Version: @(#)slip.c 0.8.3 12/24/94 |
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* |
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* Authors: Laurence Culhane, <[email protected]> |
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* Fred N. van Kempen, <[email protected]> |
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* |
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* Fixes: |
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* Alan Cox : Sanity checks and avoid tx overruns. |
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* Has a new sl->mtu field. |
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* Alan Cox : Found cause of overrun. ifconfig sl0 |
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* mtu upwards. Driver now spots this |
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* and grows/shrinks its buffers(hack!). |
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* Memory leak if you run out of memory |
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* setting up a slip driver fixed. |
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* Matt Dillon : Printable slip (borrowed from NET2E) |
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* Pauline Middelink : Slip driver fixes. |
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* Alan Cox : Honours the old SL_COMPRESSED flag |
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* Alan Cox : KISS AX.25 and AXUI IP support |
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* Michael Riepe : Automatic CSLIP recognition added |
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* Charles Hedrick : CSLIP header length problem fix. |
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* Alan Cox : Corrected non-IP cases of the above. |
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* Alan Cox : Now uses hardware type as per FvK. |
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* Alan Cox : Default to 192.168.0.0 (RFC 1597) |
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* A.N.Kuznetsov : dev_tint() recursion fix. |
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* Dmitry Gorodchanin : SLIP memory leaks |
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* Dmitry Gorodchanin : Code cleanup. Reduce tty driver |
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* buffering from 4096 to 256 bytes. |
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* Improving SLIP response time. |
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* CONFIG_SLIP_MODE_SLIP6. |
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* ifconfig sl? up & down now works |
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* correctly. |
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* Modularization. |
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* Alan Cox : Oops - fix AX.25 buffer lengths |
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* Dmitry Gorodchanin : Even more cleanups. Preserve CSLIP |
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* statistics. Include CSLIP code only |
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* if it really needed. |
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* Alan Cox : Free slhc buffers in the right place. |
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* Alan Cox : Allow for digipeated IP over AX.25 |
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* Matti Aarnio : Dynamic SLIP devices, with ideas taken |
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* from Jim Freeman's <[email protected]> |
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* dynamic PPP devices. We do NOT kfree() |
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* device entries, just reg./unreg. them |
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* as they are needed. We kfree() them |
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* at module cleanup. |
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* With MODULE-loading ``insmod'', user |
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* can issue parameter: slip_maxdev=1024 |
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* (Or how much he/she wants.. Default |
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* is 256) |
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* Stanislav Voronyi : Slip line checking, with ideas taken |
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* from multislip BSDI driver which was |
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* written by Igor Chechik, RELCOM Corp. |
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* Only algorithms have been ported to |
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* Linux SLIP driver. |
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* Vitaly E. Lavrov : Sane behaviour on tty hangup. |
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* Alexey Kuznetsov : Cleanup interfaces to tty & netdevice |
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* modules. |
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*/ |
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|
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#define SL_CHECK_TRANSMIT |
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#include <linux/compat.h> |
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#include <linux/module.h> |
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#include <linux/moduleparam.h> |
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|
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#include <linux/uaccess.h> |
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#include <linux/bitops.h> |
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#include <linux/sched/signal.h> |
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#include <linux/string.h> |
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#include <linux/mm.h> |
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#include <linux/interrupt.h> |
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#include <linux/in.h> |
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#include <linux/tty.h> |
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#include <linux/errno.h> |
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#include <linux/netdevice.h> |
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#include <linux/etherdevice.h> |
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#include <linux/skbuff.h> |
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#include <linux/rtnetlink.h> |
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#include <linux/if_arp.h> |
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#include <linux/if_slip.h> |
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#include <linux/delay.h> |
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#include <linux/init.h> |
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#include <linux/slab.h> |
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#include <linux/workqueue.h> |
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#include "slip.h" |
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#ifdef CONFIG_INET |
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#include <linux/ip.h> |
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#include <linux/tcp.h> |
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#include <net/slhc_vj.h> |
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#endif |
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|
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#define SLIP_VERSION "0.8.4-NET3.019-NEWTTY" |
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|
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static struct net_device **slip_devs; |
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|
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static int slip_maxdev = SL_NRUNIT; |
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module_param(slip_maxdev, int, 0); |
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MODULE_PARM_DESC(slip_maxdev, "Maximum number of slip devices"); |
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|
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static int slip_esc(unsigned char *p, unsigned char *d, int len); |
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static void slip_unesc(struct slip *sl, unsigned char c); |
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#ifdef CONFIG_SLIP_MODE_SLIP6 |
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static int slip_esc6(unsigned char *p, unsigned char *d, int len); |
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static void slip_unesc6(struct slip *sl, unsigned char c); |
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#endif |
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#ifdef CONFIG_SLIP_SMART |
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static void sl_keepalive(struct timer_list *t); |
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static void sl_outfill(struct timer_list *t); |
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static int sl_siocdevprivate(struct net_device *dev, struct ifreq *rq, void __user *data, int cmd); |
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#endif |
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|
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/******************************** |
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* Buffer administration routines: |
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* sl_alloc_bufs() |
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* sl_free_bufs() |
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* sl_realloc_bufs() |
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* |
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* NOTE: sl_realloc_bufs != sl_free_bufs + sl_alloc_bufs, because |
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* sl_realloc_bufs provides strong atomicity and reallocation |
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* on actively running device. |
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*********************************/ |
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|
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/* |
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Allocate channel buffers. |
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*/ |
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|
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static int sl_alloc_bufs(struct slip *sl, int mtu) |
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{ |
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int err = -ENOBUFS; |
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unsigned long len; |
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char *rbuff = NULL; |
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char *xbuff = NULL; |
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#ifdef SL_INCLUDE_CSLIP |
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char *cbuff = NULL; |
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struct slcompress *slcomp = NULL; |
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#endif |
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|
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/* |
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* Allocate the SLIP frame buffers: |
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* |
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* rbuff Receive buffer. |
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* xbuff Transmit buffer. |
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* cbuff Temporary compression buffer. |
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*/ |
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len = mtu * 2; |
|
|
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/* |
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* allow for arrival of larger UDP packets, even if we say not to |
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* also fixes a bug in which SunOS sends 512-byte packets even with |
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* an MSS of 128 |
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*/ |
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if (len < 576 * 2) |
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len = 576 * 2; |
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rbuff = kmalloc(len + 4, GFP_KERNEL); |
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if (rbuff == NULL) |
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goto err_exit; |
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xbuff = kmalloc(len + 4, GFP_KERNEL); |
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if (xbuff == NULL) |
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goto err_exit; |
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#ifdef SL_INCLUDE_CSLIP |
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cbuff = kmalloc(len + 4, GFP_KERNEL); |
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if (cbuff == NULL) |
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goto err_exit; |
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slcomp = slhc_init(16, 16); |
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if (IS_ERR(slcomp)) |
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goto err_exit; |
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#endif |
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spin_lock_bh(&sl->lock); |
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if (sl->tty == NULL) { |
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spin_unlock_bh(&sl->lock); |
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err = -ENODEV; |
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goto err_exit; |
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} |
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sl->mtu = mtu; |
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sl->buffsize = len; |
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sl->rcount = 0; |
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sl->xleft = 0; |
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rbuff = xchg(&sl->rbuff, rbuff); |
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xbuff = xchg(&sl->xbuff, xbuff); |
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#ifdef SL_INCLUDE_CSLIP |
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cbuff = xchg(&sl->cbuff, cbuff); |
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slcomp = xchg(&sl->slcomp, slcomp); |
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#endif |
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#ifdef CONFIG_SLIP_MODE_SLIP6 |
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sl->xdata = 0; |
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sl->xbits = 0; |
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#endif |
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spin_unlock_bh(&sl->lock); |
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err = 0; |
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|
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/* Cleanup */ |
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err_exit: |
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#ifdef SL_INCLUDE_CSLIP |
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kfree(cbuff); |
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slhc_free(slcomp); |
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#endif |
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kfree(xbuff); |
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kfree(rbuff); |
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return err; |
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} |
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|
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/* Free a SLIP channel buffers. */ |
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static void sl_free_bufs(struct slip *sl) |
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{ |
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/* Free all SLIP frame buffers. */ |
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kfree(xchg(&sl->rbuff, NULL)); |
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kfree(xchg(&sl->xbuff, NULL)); |
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#ifdef SL_INCLUDE_CSLIP |
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kfree(xchg(&sl->cbuff, NULL)); |
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slhc_free(xchg(&sl->slcomp, NULL)); |
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#endif |
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} |
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|
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/* |
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Reallocate slip channel buffers. |
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*/ |
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|
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static int sl_realloc_bufs(struct slip *sl, int mtu) |
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{ |
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int err = 0; |
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struct net_device *dev = sl->dev; |
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unsigned char *xbuff, *rbuff; |
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#ifdef SL_INCLUDE_CSLIP |
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unsigned char *cbuff; |
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#endif |
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int len = mtu * 2; |
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|
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/* |
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* allow for arrival of larger UDP packets, even if we say not to |
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* also fixes a bug in which SunOS sends 512-byte packets even with |
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* an MSS of 128 |
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*/ |
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if (len < 576 * 2) |
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len = 576 * 2; |
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|
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xbuff = kmalloc(len + 4, GFP_ATOMIC); |
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rbuff = kmalloc(len + 4, GFP_ATOMIC); |
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#ifdef SL_INCLUDE_CSLIP |
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cbuff = kmalloc(len + 4, GFP_ATOMIC); |
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#endif |
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|
|
|
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#ifdef SL_INCLUDE_CSLIP |
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if (xbuff == NULL || rbuff == NULL || cbuff == NULL) { |
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#else |
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if (xbuff == NULL || rbuff == NULL) { |
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#endif |
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if (mtu > sl->mtu) { |
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printk(KERN_WARNING "%s: unable to grow slip buffers, MTU change cancelled.\n", |
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dev->name); |
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err = -ENOBUFS; |
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} |
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goto done; |
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} |
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spin_lock_bh(&sl->lock); |
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|
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err = -ENODEV; |
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if (sl->tty == NULL) |
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goto done_on_bh; |
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|
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xbuff = xchg(&sl->xbuff, xbuff); |
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rbuff = xchg(&sl->rbuff, rbuff); |
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#ifdef SL_INCLUDE_CSLIP |
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cbuff = xchg(&sl->cbuff, cbuff); |
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#endif |
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if (sl->xleft) { |
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if (sl->xleft <= len) { |
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memcpy(sl->xbuff, sl->xhead, sl->xleft); |
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} else { |
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sl->xleft = 0; |
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dev->stats.tx_dropped++; |
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} |
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} |
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sl->xhead = sl->xbuff; |
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|
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if (sl->rcount) { |
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if (sl->rcount <= len) { |
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memcpy(sl->rbuff, rbuff, sl->rcount); |
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} else { |
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sl->rcount = 0; |
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dev->stats.rx_over_errors++; |
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set_bit(SLF_ERROR, &sl->flags); |
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} |
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} |
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sl->mtu = mtu; |
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dev->mtu = mtu; |
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sl->buffsize = len; |
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err = 0; |
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|
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done_on_bh: |
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spin_unlock_bh(&sl->lock); |
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|
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done: |
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kfree(xbuff); |
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kfree(rbuff); |
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#ifdef SL_INCLUDE_CSLIP |
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kfree(cbuff); |
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#endif |
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return err; |
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} |
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|
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/* Set the "sending" flag. This must be atomic hence the set_bit. */ |
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static inline void sl_lock(struct slip *sl) |
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{ |
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netif_stop_queue(sl->dev); |
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} |
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|
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|
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/* Clear the "sending" flag. This must be atomic, hence the ASM. */ |
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static inline void sl_unlock(struct slip *sl) |
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{ |
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netif_wake_queue(sl->dev); |
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} |
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|
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/* Send one completely decapsulated IP datagram to the IP layer. */ |
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static void sl_bump(struct slip *sl) |
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{ |
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struct net_device *dev = sl->dev; |
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struct sk_buff *skb; |
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int count; |
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|
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count = sl->rcount; |
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#ifdef SL_INCLUDE_CSLIP |
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if (sl->mode & (SL_MODE_ADAPTIVE | SL_MODE_CSLIP)) { |
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unsigned char c = sl->rbuff[0]; |
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if (c & SL_TYPE_COMPRESSED_TCP) { |
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/* ignore compressed packets when CSLIP is off */ |
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if (!(sl->mode & SL_MODE_CSLIP)) { |
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printk(KERN_WARNING "%s: compressed packet ignored\n", dev->name); |
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return; |
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} |
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/* make sure we've reserved enough space for uncompress |
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to use */ |
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if (count + 80 > sl->buffsize) { |
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dev->stats.rx_over_errors++; |
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return; |
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} |
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count = slhc_uncompress(sl->slcomp, sl->rbuff, count); |
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if (count <= 0) |
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return; |
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} else if (c >= SL_TYPE_UNCOMPRESSED_TCP) { |
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if (!(sl->mode & SL_MODE_CSLIP)) { |
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/* turn on header compression */ |
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sl->mode |= SL_MODE_CSLIP; |
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sl->mode &= ~SL_MODE_ADAPTIVE; |
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printk(KERN_INFO "%s: header compression turned on\n", dev->name); |
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} |
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sl->rbuff[0] &= 0x4f; |
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if (slhc_remember(sl->slcomp, sl->rbuff, count) <= 0) |
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return; |
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} |
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} |
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#endif /* SL_INCLUDE_CSLIP */ |
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|
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dev->stats.rx_bytes += count; |
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|
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skb = dev_alloc_skb(count); |
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if (skb == NULL) { |
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printk(KERN_WARNING "%s: memory squeeze, dropping packet.\n", dev->name); |
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dev->stats.rx_dropped++; |
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return; |
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} |
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skb->dev = dev; |
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skb_put_data(skb, sl->rbuff, count); |
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skb_reset_mac_header(skb); |
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skb->protocol = htons(ETH_P_IP); |
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netif_rx_ni(skb); |
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dev->stats.rx_packets++; |
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} |
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|
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/* Encapsulate one IP datagram and stuff into a TTY queue. */ |
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static void sl_encaps(struct slip *sl, unsigned char *icp, int len) |
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{ |
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unsigned char *p; |
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int actual, count; |
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|
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if (len > sl->mtu) { /* Sigh, shouldn't occur BUT ... */ |
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printk(KERN_WARNING "%s: truncating oversized transmit packet!\n", sl->dev->name); |
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sl->dev->stats.tx_dropped++; |
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sl_unlock(sl); |
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return; |
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} |
|
|
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p = icp; |
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#ifdef SL_INCLUDE_CSLIP |
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if (sl->mode & SL_MODE_CSLIP) |
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len = slhc_compress(sl->slcomp, p, len, sl->cbuff, &p, 1); |
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#endif |
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#ifdef CONFIG_SLIP_MODE_SLIP6 |
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if (sl->mode & SL_MODE_SLIP6) |
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count = slip_esc6(p, sl->xbuff, len); |
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else |
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#endif |
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count = slip_esc(p, sl->xbuff, len); |
|
|
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/* Order of next two lines is *very* important. |
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* When we are sending a little amount of data, |
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* the transfer may be completed inside the ops->write() |
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* routine, because it's running with interrupts enabled. |
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* In this case we *never* got WRITE_WAKEUP event, |
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* if we did not request it before write operation. |
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* 14 Oct 1994 Dmitry Gorodchanin. |
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*/ |
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set_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags); |
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actual = sl->tty->ops->write(sl->tty, sl->xbuff, count); |
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#ifdef SL_CHECK_TRANSMIT |
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netif_trans_update(sl->dev); |
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#endif |
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sl->xleft = count - actual; |
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sl->xhead = sl->xbuff + actual; |
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#ifdef CONFIG_SLIP_SMART |
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/* VSV */ |
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clear_bit(SLF_OUTWAIT, &sl->flags); /* reset outfill flag */ |
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#endif |
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} |
|
|
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/* Write out any remaining transmit buffer. Scheduled when tty is writable */ |
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static void slip_transmit(struct work_struct *work) |
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{ |
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struct slip *sl = container_of(work, struct slip, tx_work); |
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int actual; |
|
|
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spin_lock_bh(&sl->lock); |
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/* First make sure we're connected. */ |
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if (!sl->tty || sl->magic != SLIP_MAGIC || !netif_running(sl->dev)) { |
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spin_unlock_bh(&sl->lock); |
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return; |
|
} |
|
|
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if (sl->xleft <= 0) { |
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/* Now serial buffer is almost free & we can start |
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* transmission of another packet */ |
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sl->dev->stats.tx_packets++; |
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clear_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags); |
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spin_unlock_bh(&sl->lock); |
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sl_unlock(sl); |
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return; |
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} |
|
|
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actual = sl->tty->ops->write(sl->tty, sl->xhead, sl->xleft); |
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sl->xleft -= actual; |
|
sl->xhead += actual; |
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spin_unlock_bh(&sl->lock); |
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} |
|
|
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/* |
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* Called by the driver when there's room for more data. |
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* Schedule the transmit. |
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*/ |
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static void slip_write_wakeup(struct tty_struct *tty) |
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{ |
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struct slip *sl; |
|
|
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rcu_read_lock(); |
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sl = rcu_dereference(tty->disc_data); |
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if (sl) |
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schedule_work(&sl->tx_work); |
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rcu_read_unlock(); |
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} |
|
|
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static void sl_tx_timeout(struct net_device *dev, unsigned int txqueue) |
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{ |
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struct slip *sl = netdev_priv(dev); |
|
|
|
spin_lock(&sl->lock); |
|
|
|
if (netif_queue_stopped(dev)) { |
|
if (!netif_running(dev)) |
|
goto out; |
|
|
|
/* May be we must check transmitter timeout here ? |
|
* 14 Oct 1994 Dmitry Gorodchanin. |
|
*/ |
|
#ifdef SL_CHECK_TRANSMIT |
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if (time_before(jiffies, dev_trans_start(dev) + 20 * HZ)) { |
|
/* 20 sec timeout not reached */ |
|
goto out; |
|
} |
|
printk(KERN_WARNING "%s: transmit timed out, %s?\n", |
|
dev->name, |
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(tty_chars_in_buffer(sl->tty) || sl->xleft) ? |
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"bad line quality" : "driver error"); |
|
sl->xleft = 0; |
|
clear_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags); |
|
sl_unlock(sl); |
|
#endif |
|
} |
|
out: |
|
spin_unlock(&sl->lock); |
|
} |
|
|
|
|
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/* Encapsulate an IP datagram and kick it into a TTY queue. */ |
|
static netdev_tx_t |
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sl_xmit(struct sk_buff *skb, struct net_device *dev) |
|
{ |
|
struct slip *sl = netdev_priv(dev); |
|
|
|
spin_lock(&sl->lock); |
|
if (!netif_running(dev)) { |
|
spin_unlock(&sl->lock); |
|
printk(KERN_WARNING "%s: xmit call when iface is down\n", dev->name); |
|
dev_kfree_skb(skb); |
|
return NETDEV_TX_OK; |
|
} |
|
if (sl->tty == NULL) { |
|
spin_unlock(&sl->lock); |
|
dev_kfree_skb(skb); |
|
return NETDEV_TX_OK; |
|
} |
|
|
|
sl_lock(sl); |
|
dev->stats.tx_bytes += skb->len; |
|
sl_encaps(sl, skb->data, skb->len); |
|
spin_unlock(&sl->lock); |
|
|
|
dev_kfree_skb(skb); |
|
return NETDEV_TX_OK; |
|
} |
|
|
|
|
|
/****************************************** |
|
* Routines looking at netdevice side. |
|
******************************************/ |
|
|
|
/* Netdevice UP -> DOWN routine */ |
|
|
|
static int |
|
sl_close(struct net_device *dev) |
|
{ |
|
struct slip *sl = netdev_priv(dev); |
|
|
|
spin_lock_bh(&sl->lock); |
|
if (sl->tty) |
|
/* TTY discipline is running. */ |
|
clear_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags); |
|
netif_stop_queue(dev); |
|
sl->rcount = 0; |
|
sl->xleft = 0; |
|
spin_unlock_bh(&sl->lock); |
|
|
|
return 0; |
|
} |
|
|
|
/* Netdevice DOWN -> UP routine */ |
|
|
|
static int sl_open(struct net_device *dev) |
|
{ |
|
struct slip *sl = netdev_priv(dev); |
|
|
|
if (sl->tty == NULL) |
|
return -ENODEV; |
|
|
|
sl->flags &= (1 << SLF_INUSE); |
|
netif_start_queue(dev); |
|
return 0; |
|
} |
|
|
|
/* Netdevice change MTU request */ |
|
|
|
static int sl_change_mtu(struct net_device *dev, int new_mtu) |
|
{ |
|
struct slip *sl = netdev_priv(dev); |
|
|
|
return sl_realloc_bufs(sl, new_mtu); |
|
} |
|
|
|
/* Netdevice get statistics request */ |
|
|
|
static void |
|
sl_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats) |
|
{ |
|
struct net_device_stats *devstats = &dev->stats; |
|
#ifdef SL_INCLUDE_CSLIP |
|
struct slip *sl = netdev_priv(dev); |
|
struct slcompress *comp = sl->slcomp; |
|
#endif |
|
stats->rx_packets = devstats->rx_packets; |
|
stats->tx_packets = devstats->tx_packets; |
|
stats->rx_bytes = devstats->rx_bytes; |
|
stats->tx_bytes = devstats->tx_bytes; |
|
stats->rx_dropped = devstats->rx_dropped; |
|
stats->tx_dropped = devstats->tx_dropped; |
|
stats->tx_errors = devstats->tx_errors; |
|
stats->rx_errors = devstats->rx_errors; |
|
stats->rx_over_errors = devstats->rx_over_errors; |
|
|
|
#ifdef SL_INCLUDE_CSLIP |
|
if (comp) { |
|
/* Generic compressed statistics */ |
|
stats->rx_compressed = comp->sls_i_compressed; |
|
stats->tx_compressed = comp->sls_o_compressed; |
|
|
|
/* Are we really still needs this? */ |
|
stats->rx_fifo_errors += comp->sls_i_compressed; |
|
stats->rx_dropped += comp->sls_i_tossed; |
|
stats->tx_fifo_errors += comp->sls_o_compressed; |
|
stats->collisions += comp->sls_o_misses; |
|
} |
|
#endif |
|
} |
|
|
|
/* Netdevice register callback */ |
|
|
|
static int sl_init(struct net_device *dev) |
|
{ |
|
struct slip *sl = netdev_priv(dev); |
|
|
|
/* |
|
* Finish setting up the DEVICE info. |
|
*/ |
|
|
|
dev->mtu = sl->mtu; |
|
dev->type = ARPHRD_SLIP + sl->mode; |
|
#ifdef SL_CHECK_TRANSMIT |
|
dev->watchdog_timeo = 20*HZ; |
|
#endif |
|
return 0; |
|
} |
|
|
|
|
|
static void sl_uninit(struct net_device *dev) |
|
{ |
|
struct slip *sl = netdev_priv(dev); |
|
|
|
sl_free_bufs(sl); |
|
} |
|
|
|
/* Hook the destructor so we can free slip devices at the right point in time */ |
|
static void sl_free_netdev(struct net_device *dev) |
|
{ |
|
int i = dev->base_addr; |
|
|
|
slip_devs[i] = NULL; |
|
} |
|
|
|
static const struct net_device_ops sl_netdev_ops = { |
|
.ndo_init = sl_init, |
|
.ndo_uninit = sl_uninit, |
|
.ndo_open = sl_open, |
|
.ndo_stop = sl_close, |
|
.ndo_start_xmit = sl_xmit, |
|
.ndo_get_stats64 = sl_get_stats64, |
|
.ndo_change_mtu = sl_change_mtu, |
|
.ndo_tx_timeout = sl_tx_timeout, |
|
#ifdef CONFIG_SLIP_SMART |
|
.ndo_siocdevprivate = sl_siocdevprivate, |
|
#endif |
|
}; |
|
|
|
|
|
static void sl_setup(struct net_device *dev) |
|
{ |
|
dev->netdev_ops = &sl_netdev_ops; |
|
dev->needs_free_netdev = true; |
|
dev->priv_destructor = sl_free_netdev; |
|
|
|
dev->hard_header_len = 0; |
|
dev->addr_len = 0; |
|
dev->tx_queue_len = 10; |
|
|
|
/* MTU range: 68 - 65534 */ |
|
dev->min_mtu = 68; |
|
dev->max_mtu = 65534; |
|
|
|
/* New-style flags. */ |
|
dev->flags = IFF_NOARP|IFF_POINTOPOINT|IFF_MULTICAST; |
|
} |
|
|
|
/****************************************** |
|
Routines looking at TTY side. |
|
******************************************/ |
|
|
|
|
|
/* |
|
* Handle the 'receiver data ready' interrupt. |
|
* This function is called by the 'tty_io' module in the kernel when |
|
* a block of SLIP data has been received, which can now be decapsulated |
|
* and sent on to some IP layer for further processing. This will not |
|
* be re-entered while running but other ldisc functions may be called |
|
* in parallel |
|
*/ |
|
|
|
static void slip_receive_buf(struct tty_struct *tty, const unsigned char *cp, |
|
const char *fp, int count) |
|
{ |
|
struct slip *sl = tty->disc_data; |
|
|
|
if (!sl || sl->magic != SLIP_MAGIC || !netif_running(sl->dev)) |
|
return; |
|
|
|
/* Read the characters out of the buffer */ |
|
while (count--) { |
|
if (fp && *fp++) { |
|
if (!test_and_set_bit(SLF_ERROR, &sl->flags)) |
|
sl->dev->stats.rx_errors++; |
|
cp++; |
|
continue; |
|
} |
|
#ifdef CONFIG_SLIP_MODE_SLIP6 |
|
if (sl->mode & SL_MODE_SLIP6) |
|
slip_unesc6(sl, *cp++); |
|
else |
|
#endif |
|
slip_unesc(sl, *cp++); |
|
} |
|
} |
|
|
|
/************************************ |
|
* slip_open helper routines. |
|
************************************/ |
|
|
|
/* Collect hanged up channels */ |
|
static void sl_sync(void) |
|
{ |
|
int i; |
|
struct net_device *dev; |
|
struct slip *sl; |
|
|
|
for (i = 0; i < slip_maxdev; i++) { |
|
dev = slip_devs[i]; |
|
if (dev == NULL) |
|
break; |
|
|
|
sl = netdev_priv(dev); |
|
if (sl->tty || sl->leased) |
|
continue; |
|
if (dev->flags & IFF_UP) |
|
dev_close(dev); |
|
} |
|
} |
|
|
|
|
|
/* Find a free SLIP channel, and link in this `tty' line. */ |
|
static struct slip *sl_alloc(void) |
|
{ |
|
int i; |
|
char name[IFNAMSIZ]; |
|
struct net_device *dev = NULL; |
|
struct slip *sl; |
|
|
|
for (i = 0; i < slip_maxdev; i++) { |
|
dev = slip_devs[i]; |
|
if (dev == NULL) |
|
break; |
|
} |
|
/* Sorry, too many, all slots in use */ |
|
if (i >= slip_maxdev) |
|
return NULL; |
|
|
|
sprintf(name, "sl%d", i); |
|
dev = alloc_netdev(sizeof(*sl), name, NET_NAME_UNKNOWN, sl_setup); |
|
if (!dev) |
|
return NULL; |
|
|
|
dev->base_addr = i; |
|
sl = netdev_priv(dev); |
|
|
|
/* Initialize channel control data */ |
|
sl->magic = SLIP_MAGIC; |
|
sl->dev = dev; |
|
spin_lock_init(&sl->lock); |
|
INIT_WORK(&sl->tx_work, slip_transmit); |
|
sl->mode = SL_MODE_DEFAULT; |
|
#ifdef CONFIG_SLIP_SMART |
|
/* initialize timer_list struct */ |
|
timer_setup(&sl->keepalive_timer, sl_keepalive, 0); |
|
timer_setup(&sl->outfill_timer, sl_outfill, 0); |
|
#endif |
|
slip_devs[i] = dev; |
|
return sl; |
|
} |
|
|
|
/* |
|
* Open the high-level part of the SLIP channel. |
|
* This function is called by the TTY module when the |
|
* SLIP line discipline is called for. Because we are |
|
* sure the tty line exists, we only have to link it to |
|
* a free SLIP channel... |
|
* |
|
* Called in process context serialized from other ldisc calls. |
|
*/ |
|
|
|
static int slip_open(struct tty_struct *tty) |
|
{ |
|
struct slip *sl; |
|
int err; |
|
|
|
if (!capable(CAP_NET_ADMIN)) |
|
return -EPERM; |
|
|
|
if (tty->ops->write == NULL) |
|
return -EOPNOTSUPP; |
|
|
|
/* RTnetlink lock is misused here to serialize concurrent |
|
opens of slip channels. There are better ways, but it is |
|
the simplest one. |
|
*/ |
|
rtnl_lock(); |
|
|
|
/* Collect hanged up channels. */ |
|
sl_sync(); |
|
|
|
sl = tty->disc_data; |
|
|
|
err = -EEXIST; |
|
/* First make sure we're not already connected. */ |
|
if (sl && sl->magic == SLIP_MAGIC) |
|
goto err_exit; |
|
|
|
/* OK. Find a free SLIP channel to use. */ |
|
err = -ENFILE; |
|
sl = sl_alloc(); |
|
if (sl == NULL) |
|
goto err_exit; |
|
|
|
sl->tty = tty; |
|
tty->disc_data = sl; |
|
sl->pid = current->pid; |
|
|
|
if (!test_bit(SLF_INUSE, &sl->flags)) { |
|
/* Perform the low-level SLIP initialization. */ |
|
err = sl_alloc_bufs(sl, SL_MTU); |
|
if (err) |
|
goto err_free_chan; |
|
|
|
set_bit(SLF_INUSE, &sl->flags); |
|
|
|
err = register_netdevice(sl->dev); |
|
if (err) |
|
goto err_free_bufs; |
|
} |
|
|
|
#ifdef CONFIG_SLIP_SMART |
|
if (sl->keepalive) { |
|
sl->keepalive_timer.expires = jiffies + sl->keepalive * HZ; |
|
add_timer(&sl->keepalive_timer); |
|
} |
|
if (sl->outfill) { |
|
sl->outfill_timer.expires = jiffies + sl->outfill * HZ; |
|
add_timer(&sl->outfill_timer); |
|
} |
|
#endif |
|
|
|
/* Done. We have linked the TTY line to a channel. */ |
|
rtnl_unlock(); |
|
tty->receive_room = 65536; /* We don't flow control */ |
|
|
|
/* TTY layer expects 0 on success */ |
|
return 0; |
|
|
|
err_free_bufs: |
|
sl_free_bufs(sl); |
|
|
|
err_free_chan: |
|
sl->tty = NULL; |
|
tty->disc_data = NULL; |
|
clear_bit(SLF_INUSE, &sl->flags); |
|
sl_free_netdev(sl->dev); |
|
/* do not call free_netdev before rtnl_unlock */ |
|
rtnl_unlock(); |
|
free_netdev(sl->dev); |
|
return err; |
|
|
|
err_exit: |
|
rtnl_unlock(); |
|
|
|
/* Count references from TTY module */ |
|
return err; |
|
} |
|
|
|
/* |
|
* Close down a SLIP channel. |
|
* This means flushing out any pending queues, and then returning. This |
|
* call is serialized against other ldisc functions. |
|
* |
|
* We also use this method fo a hangup event |
|
*/ |
|
|
|
static void slip_close(struct tty_struct *tty) |
|
{ |
|
struct slip *sl = tty->disc_data; |
|
|
|
/* First make sure we're connected. */ |
|
if (!sl || sl->magic != SLIP_MAGIC || sl->tty != tty) |
|
return; |
|
|
|
spin_lock_bh(&sl->lock); |
|
rcu_assign_pointer(tty->disc_data, NULL); |
|
sl->tty = NULL; |
|
spin_unlock_bh(&sl->lock); |
|
|
|
synchronize_rcu(); |
|
flush_work(&sl->tx_work); |
|
|
|
/* VSV = very important to remove timers */ |
|
#ifdef CONFIG_SLIP_SMART |
|
del_timer_sync(&sl->keepalive_timer); |
|
del_timer_sync(&sl->outfill_timer); |
|
#endif |
|
/* Flush network side */ |
|
unregister_netdev(sl->dev); |
|
/* This will complete via sl_free_netdev */ |
|
} |
|
|
|
static int slip_hangup(struct tty_struct *tty) |
|
{ |
|
slip_close(tty); |
|
return 0; |
|
} |
|
/************************************************************************ |
|
* STANDARD SLIP ENCAPSULATION * |
|
************************************************************************/ |
|
|
|
static int slip_esc(unsigned char *s, unsigned char *d, int len) |
|
{ |
|
unsigned char *ptr = d; |
|
unsigned char c; |
|
|
|
/* |
|
* Send an initial END character to flush out any |
|
* data that may have accumulated in the receiver |
|
* due to line noise. |
|
*/ |
|
|
|
*ptr++ = END; |
|
|
|
/* |
|
* For each byte in the packet, send the appropriate |
|
* character sequence, according to the SLIP protocol. |
|
*/ |
|
|
|
while (len-- > 0) { |
|
switch (c = *s++) { |
|
case END: |
|
*ptr++ = ESC; |
|
*ptr++ = ESC_END; |
|
break; |
|
case ESC: |
|
*ptr++ = ESC; |
|
*ptr++ = ESC_ESC; |
|
break; |
|
default: |
|
*ptr++ = c; |
|
break; |
|
} |
|
} |
|
*ptr++ = END; |
|
return ptr - d; |
|
} |
|
|
|
static void slip_unesc(struct slip *sl, unsigned char s) |
|
{ |
|
|
|
switch (s) { |
|
case END: |
|
#ifdef CONFIG_SLIP_SMART |
|
/* drop keeptest bit = VSV */ |
|
if (test_bit(SLF_KEEPTEST, &sl->flags)) |
|
clear_bit(SLF_KEEPTEST, &sl->flags); |
|
#endif |
|
|
|
if (!test_and_clear_bit(SLF_ERROR, &sl->flags) && |
|
(sl->rcount > 2)) |
|
sl_bump(sl); |
|
clear_bit(SLF_ESCAPE, &sl->flags); |
|
sl->rcount = 0; |
|
return; |
|
|
|
case ESC: |
|
set_bit(SLF_ESCAPE, &sl->flags); |
|
return; |
|
case ESC_ESC: |
|
if (test_and_clear_bit(SLF_ESCAPE, &sl->flags)) |
|
s = ESC; |
|
break; |
|
case ESC_END: |
|
if (test_and_clear_bit(SLF_ESCAPE, &sl->flags)) |
|
s = END; |
|
break; |
|
} |
|
if (!test_bit(SLF_ERROR, &sl->flags)) { |
|
if (sl->rcount < sl->buffsize) { |
|
sl->rbuff[sl->rcount++] = s; |
|
return; |
|
} |
|
sl->dev->stats.rx_over_errors++; |
|
set_bit(SLF_ERROR, &sl->flags); |
|
} |
|
} |
|
|
|
|
|
#ifdef CONFIG_SLIP_MODE_SLIP6 |
|
/************************************************************************ |
|
* 6 BIT SLIP ENCAPSULATION * |
|
************************************************************************/ |
|
|
|
static int slip_esc6(unsigned char *s, unsigned char *d, int len) |
|
{ |
|
unsigned char *ptr = d; |
|
unsigned char c; |
|
int i; |
|
unsigned short v = 0; |
|
short bits = 0; |
|
|
|
/* |
|
* Send an initial END character to flush out any |
|
* data that may have accumulated in the receiver |
|
* due to line noise. |
|
*/ |
|
|
|
*ptr++ = 0x70; |
|
|
|
/* |
|
* Encode the packet into printable ascii characters |
|
*/ |
|
|
|
for (i = 0; i < len; ++i) { |
|
v = (v << 8) | s[i]; |
|
bits += 8; |
|
while (bits >= 6) { |
|
bits -= 6; |
|
c = 0x30 + ((v >> bits) & 0x3F); |
|
*ptr++ = c; |
|
} |
|
} |
|
if (bits) { |
|
c = 0x30 + ((v << (6 - bits)) & 0x3F); |
|
*ptr++ = c; |
|
} |
|
*ptr++ = 0x70; |
|
return ptr - d; |
|
} |
|
|
|
static void slip_unesc6(struct slip *sl, unsigned char s) |
|
{ |
|
unsigned char c; |
|
|
|
if (s == 0x70) { |
|
#ifdef CONFIG_SLIP_SMART |
|
/* drop keeptest bit = VSV */ |
|
if (test_bit(SLF_KEEPTEST, &sl->flags)) |
|
clear_bit(SLF_KEEPTEST, &sl->flags); |
|
#endif |
|
|
|
if (!test_and_clear_bit(SLF_ERROR, &sl->flags) && |
|
(sl->rcount > 2)) |
|
sl_bump(sl); |
|
sl->rcount = 0; |
|
sl->xbits = 0; |
|
sl->xdata = 0; |
|
} else if (s >= 0x30 && s < 0x70) { |
|
sl->xdata = (sl->xdata << 6) | ((s - 0x30) & 0x3F); |
|
sl->xbits += 6; |
|
if (sl->xbits >= 8) { |
|
sl->xbits -= 8; |
|
c = (unsigned char)(sl->xdata >> sl->xbits); |
|
if (!test_bit(SLF_ERROR, &sl->flags)) { |
|
if (sl->rcount < sl->buffsize) { |
|
sl->rbuff[sl->rcount++] = c; |
|
return; |
|
} |
|
sl->dev->stats.rx_over_errors++; |
|
set_bit(SLF_ERROR, &sl->flags); |
|
} |
|
} |
|
} |
|
} |
|
#endif /* CONFIG_SLIP_MODE_SLIP6 */ |
|
|
|
/* Perform I/O control on an active SLIP channel. */ |
|
static int slip_ioctl(struct tty_struct *tty, struct file *file, |
|
unsigned int cmd, unsigned long arg) |
|
{ |
|
struct slip *sl = tty->disc_data; |
|
unsigned int tmp; |
|
int __user *p = (int __user *)arg; |
|
|
|
/* First make sure we're connected. */ |
|
if (!sl || sl->magic != SLIP_MAGIC) |
|
return -EINVAL; |
|
|
|
switch (cmd) { |
|
case SIOCGIFNAME: |
|
tmp = strlen(sl->dev->name) + 1; |
|
if (copy_to_user((void __user *)arg, sl->dev->name, tmp)) |
|
return -EFAULT; |
|
return 0; |
|
|
|
case SIOCGIFENCAP: |
|
if (put_user(sl->mode, p)) |
|
return -EFAULT; |
|
return 0; |
|
|
|
case SIOCSIFENCAP: |
|
if (get_user(tmp, p)) |
|
return -EFAULT; |
|
#ifndef SL_INCLUDE_CSLIP |
|
if (tmp & (SL_MODE_CSLIP|SL_MODE_ADAPTIVE)) |
|
return -EINVAL; |
|
#else |
|
if ((tmp & (SL_MODE_ADAPTIVE | SL_MODE_CSLIP)) == |
|
(SL_MODE_ADAPTIVE | SL_MODE_CSLIP)) |
|
/* return -EINVAL; */ |
|
tmp &= ~SL_MODE_ADAPTIVE; |
|
#endif |
|
#ifndef CONFIG_SLIP_MODE_SLIP6 |
|
if (tmp & SL_MODE_SLIP6) |
|
return -EINVAL; |
|
#endif |
|
sl->mode = tmp; |
|
sl->dev->type = ARPHRD_SLIP + sl->mode; |
|
return 0; |
|
|
|
case SIOCSIFHWADDR: |
|
return -EINVAL; |
|
|
|
#ifdef CONFIG_SLIP_SMART |
|
/* VSV changes start here */ |
|
case SIOCSKEEPALIVE: |
|
if (get_user(tmp, p)) |
|
return -EFAULT; |
|
if (tmp > 255) /* max for unchar */ |
|
return -EINVAL; |
|
|
|
spin_lock_bh(&sl->lock); |
|
if (!sl->tty) { |
|
spin_unlock_bh(&sl->lock); |
|
return -ENODEV; |
|
} |
|
sl->keepalive = (u8)tmp; |
|
if (sl->keepalive != 0) { |
|
mod_timer(&sl->keepalive_timer, |
|
jiffies + sl->keepalive * HZ); |
|
set_bit(SLF_KEEPTEST, &sl->flags); |
|
} else |
|
del_timer(&sl->keepalive_timer); |
|
spin_unlock_bh(&sl->lock); |
|
return 0; |
|
|
|
case SIOCGKEEPALIVE: |
|
if (put_user(sl->keepalive, p)) |
|
return -EFAULT; |
|
return 0; |
|
|
|
case SIOCSOUTFILL: |
|
if (get_user(tmp, p)) |
|
return -EFAULT; |
|
if (tmp > 255) /* max for unchar */ |
|
return -EINVAL; |
|
spin_lock_bh(&sl->lock); |
|
if (!sl->tty) { |
|
spin_unlock_bh(&sl->lock); |
|
return -ENODEV; |
|
} |
|
sl->outfill = (u8)tmp; |
|
if (sl->outfill != 0) { |
|
mod_timer(&sl->outfill_timer, |
|
jiffies + sl->outfill * HZ); |
|
set_bit(SLF_OUTWAIT, &sl->flags); |
|
} else |
|
del_timer(&sl->outfill_timer); |
|
spin_unlock_bh(&sl->lock); |
|
return 0; |
|
|
|
case SIOCGOUTFILL: |
|
if (put_user(sl->outfill, p)) |
|
return -EFAULT; |
|
return 0; |
|
/* VSV changes end */ |
|
#endif |
|
default: |
|
return tty_mode_ioctl(tty, file, cmd, arg); |
|
} |
|
} |
|
|
|
/* VSV changes start here */ |
|
#ifdef CONFIG_SLIP_SMART |
|
/* function sl_siocdevprivate called from net/core/dev.c |
|
to allow get/set outfill/keepalive parameter |
|
by ifconfig */ |
|
|
|
static int sl_siocdevprivate(struct net_device *dev, struct ifreq *rq, |
|
void __user *data, int cmd) |
|
{ |
|
struct slip *sl = netdev_priv(dev); |
|
unsigned long *p = (unsigned long *)&rq->ifr_ifru; |
|
|
|
if (sl == NULL) /* Allocation failed ?? */ |
|
return -ENODEV; |
|
|
|
if (in_compat_syscall()) |
|
return -EOPNOTSUPP; |
|
|
|
spin_lock_bh(&sl->lock); |
|
|
|
if (!sl->tty) { |
|
spin_unlock_bh(&sl->lock); |
|
return -ENODEV; |
|
} |
|
|
|
switch (cmd) { |
|
case SIOCSKEEPALIVE: |
|
/* max for unchar */ |
|
if ((unsigned)*p > 255) { |
|
spin_unlock_bh(&sl->lock); |
|
return -EINVAL; |
|
} |
|
sl->keepalive = (u8)*p; |
|
if (sl->keepalive != 0) { |
|
sl->keepalive_timer.expires = |
|
jiffies + sl->keepalive * HZ; |
|
mod_timer(&sl->keepalive_timer, |
|
jiffies + sl->keepalive * HZ); |
|
set_bit(SLF_KEEPTEST, &sl->flags); |
|
} else |
|
del_timer(&sl->keepalive_timer); |
|
break; |
|
|
|
case SIOCGKEEPALIVE: |
|
*p = sl->keepalive; |
|
break; |
|
|
|
case SIOCSOUTFILL: |
|
if ((unsigned)*p > 255) { /* max for unchar */ |
|
spin_unlock_bh(&sl->lock); |
|
return -EINVAL; |
|
} |
|
sl->outfill = (u8)*p; |
|
if (sl->outfill != 0) { |
|
mod_timer(&sl->outfill_timer, |
|
jiffies + sl->outfill * HZ); |
|
set_bit(SLF_OUTWAIT, &sl->flags); |
|
} else |
|
del_timer(&sl->outfill_timer); |
|
break; |
|
|
|
case SIOCGOUTFILL: |
|
*p = sl->outfill; |
|
break; |
|
|
|
case SIOCSLEASE: |
|
/* Resolve race condition, when ioctl'ing hanged up |
|
and opened by another process device. |
|
*/ |
|
if (sl->tty != current->signal->tty && |
|
sl->pid != current->pid) { |
|
spin_unlock_bh(&sl->lock); |
|
return -EPERM; |
|
} |
|
sl->leased = 0; |
|
if (*p) |
|
sl->leased = 1; |
|
break; |
|
|
|
case SIOCGLEASE: |
|
*p = sl->leased; |
|
} |
|
spin_unlock_bh(&sl->lock); |
|
return 0; |
|
} |
|
#endif |
|
/* VSV changes end */ |
|
|
|
static struct tty_ldisc_ops sl_ldisc = { |
|
.owner = THIS_MODULE, |
|
.num = N_SLIP, |
|
.name = "slip", |
|
.open = slip_open, |
|
.close = slip_close, |
|
.hangup = slip_hangup, |
|
.ioctl = slip_ioctl, |
|
.receive_buf = slip_receive_buf, |
|
.write_wakeup = slip_write_wakeup, |
|
}; |
|
|
|
static int __init slip_init(void) |
|
{ |
|
int status; |
|
|
|
if (slip_maxdev < 4) |
|
slip_maxdev = 4; /* Sanity */ |
|
|
|
printk(KERN_INFO "SLIP: version %s (dynamic channels, max=%d)" |
|
#ifdef CONFIG_SLIP_MODE_SLIP6 |
|
" (6 bit encapsulation enabled)" |
|
#endif |
|
".\n", |
|
SLIP_VERSION, slip_maxdev); |
|
#if defined(SL_INCLUDE_CSLIP) |
|
printk(KERN_INFO "CSLIP: code copyright 1989 Regents of the University of California.\n"); |
|
#endif |
|
#ifdef CONFIG_SLIP_SMART |
|
printk(KERN_INFO "SLIP linefill/keepalive option.\n"); |
|
#endif |
|
|
|
slip_devs = kcalloc(slip_maxdev, sizeof(struct net_device *), |
|
GFP_KERNEL); |
|
if (!slip_devs) |
|
return -ENOMEM; |
|
|
|
/* Fill in our line protocol discipline, and register it */ |
|
status = tty_register_ldisc(&sl_ldisc); |
|
if (status != 0) { |
|
printk(KERN_ERR "SLIP: can't register line discipline (err = %d)\n", status); |
|
kfree(slip_devs); |
|
} |
|
return status; |
|
} |
|
|
|
static void __exit slip_exit(void) |
|
{ |
|
int i; |
|
struct net_device *dev; |
|
struct slip *sl; |
|
unsigned long timeout = jiffies + HZ; |
|
int busy = 0; |
|
|
|
if (slip_devs == NULL) |
|
return; |
|
|
|
/* First of all: check for active disciplines and hangup them. |
|
*/ |
|
do { |
|
if (busy) |
|
msleep_interruptible(100); |
|
|
|
busy = 0; |
|
for (i = 0; i < slip_maxdev; i++) { |
|
dev = slip_devs[i]; |
|
if (!dev) |
|
continue; |
|
sl = netdev_priv(dev); |
|
spin_lock_bh(&sl->lock); |
|
if (sl->tty) { |
|
busy++; |
|
tty_hangup(sl->tty); |
|
} |
|
spin_unlock_bh(&sl->lock); |
|
} |
|
} while (busy && time_before(jiffies, timeout)); |
|
|
|
/* FIXME: hangup is async so we should wait when doing this second |
|
phase */ |
|
|
|
for (i = 0; i < slip_maxdev; i++) { |
|
dev = slip_devs[i]; |
|
if (!dev) |
|
continue; |
|
slip_devs[i] = NULL; |
|
|
|
sl = netdev_priv(dev); |
|
if (sl->tty) { |
|
printk(KERN_ERR "%s: tty discipline still running\n", |
|
dev->name); |
|
} |
|
|
|
unregister_netdev(dev); |
|
} |
|
|
|
kfree(slip_devs); |
|
slip_devs = NULL; |
|
|
|
tty_unregister_ldisc(&sl_ldisc); |
|
} |
|
|
|
module_init(slip_init); |
|
module_exit(slip_exit); |
|
|
|
#ifdef CONFIG_SLIP_SMART |
|
/* |
|
* This is start of the code for multislip style line checking |
|
* added by Stanislav Voronyi. All changes before marked VSV |
|
*/ |
|
|
|
static void sl_outfill(struct timer_list *t) |
|
{ |
|
struct slip *sl = from_timer(sl, t, outfill_timer); |
|
|
|
spin_lock(&sl->lock); |
|
|
|
if (sl->tty == NULL) |
|
goto out; |
|
|
|
if (sl->outfill) { |
|
if (test_bit(SLF_OUTWAIT, &sl->flags)) { |
|
/* no packets were transmitted, do outfill */ |
|
#ifdef CONFIG_SLIP_MODE_SLIP6 |
|
unsigned char s = (sl->mode & SL_MODE_SLIP6)?0x70:END; |
|
#else |
|
unsigned char s = END; |
|
#endif |
|
/* put END into tty queue. Is it right ??? */ |
|
if (!netif_queue_stopped(sl->dev)) { |
|
/* if device busy no outfill */ |
|
sl->tty->ops->write(sl->tty, &s, 1); |
|
} |
|
} else |
|
set_bit(SLF_OUTWAIT, &sl->flags); |
|
|
|
mod_timer(&sl->outfill_timer, jiffies+sl->outfill*HZ); |
|
} |
|
out: |
|
spin_unlock(&sl->lock); |
|
} |
|
|
|
static void sl_keepalive(struct timer_list *t) |
|
{ |
|
struct slip *sl = from_timer(sl, t, keepalive_timer); |
|
|
|
spin_lock(&sl->lock); |
|
|
|
if (sl->tty == NULL) |
|
goto out; |
|
|
|
if (sl->keepalive) { |
|
if (test_bit(SLF_KEEPTEST, &sl->flags)) { |
|
/* keepalive still high :(, we must hangup */ |
|
if (sl->outfill) |
|
/* outfill timer must be deleted too */ |
|
(void)del_timer(&sl->outfill_timer); |
|
printk(KERN_DEBUG "%s: no packets received during keepalive timeout, hangup.\n", sl->dev->name); |
|
/* this must hangup tty & close slip */ |
|
tty_hangup(sl->tty); |
|
/* I think we need not something else */ |
|
goto out; |
|
} else |
|
set_bit(SLF_KEEPTEST, &sl->flags); |
|
|
|
mod_timer(&sl->keepalive_timer, jiffies+sl->keepalive*HZ); |
|
} |
|
out: |
|
spin_unlock(&sl->lock); |
|
} |
|
|
|
#endif |
|
MODULE_LICENSE("GPL"); |
|
MODULE_ALIAS_LDISC(N_SLIP);
|
|
|