* [PATCH] 2nd 6pack patch for 2.6.4
@ 2004-03-15 18:42 Ralf Baechle DO1GRB
0 siblings, 0 replies; only message in thread
From: Ralf Baechle DO1GRB @ 2004-03-15 18:42 UTC (permalink / raw)
To: linux-hams
Hi,
below is the second 6pack patch. A few more cleanups and most important,
it now actually tries to get the locking of the tty right, so the potencial
of crashes on shutdown should now hopefully be fixed.
As before reports will be appreciated. I don't have 6pack hardware so I'm
limited to test this with a TNC simulator which is only a few hours old,
so beware ...
73 de DO1GRB op Ralf
--
Loc. JN47BS / CQ 14 / ITU 28 / DOK A21
Index: drivers/net/hamradio/6pack.c
===================================================================
RCS file: /home/cvs/linux/drivers/net/hamradio/6pack.c,v
retrieving revision 1.20
diff -u -r1.20 6pack.c
--- drivers/net/hamradio/6pack.c 11 Mar 2004 16:46:51 -0000 1.20
+++ drivers/net/hamradio/6pack.c 15 Mar 2004 18:29:03 -0000
@@ -3,15 +3,13 @@
* devices like TTY. It interfaces between a raw TTY and the
* kernel's AX.25 protocol layers.
*
- * Version: @(#)6pack.c 0.3.0 04/07/98
- *
* Authors: Andreas Könsgen <ajk@iehk.rwth-aachen.de>
+ * Ralf Baechle DO1GRB <ralf@linux-mips.org>
*
- * Quite a lot of stuff "stolen" by Jörg Reuter from slip.c, written by
+ * Quite a lot of stuff "stolen" by Joerg Reuter from slip.c, written by
*
* Laurence Culhane, <loz@holmes.demon.co.uk>
* Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org>
- *
*/
#include <linux/config.h>
@@ -31,20 +29,23 @@
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/rtnetlink.h>
+#include <linux/spinlock.h>
#include <linux/if_arp.h>
#include <linux/init.h>
#include <linux/ip.h>
#include <linux/tcp.h>
+#include <asm/semaphore.h>
+#include <asm/atomic.h>
#define SIXPACK_VERSION "Revision: 0.3.0"
/* sixpack priority commands */
-#define SIXP_SEOF 0x40 /* start and end of a 6pack frame */
-#define SIXP_TX_URUN 0x48 /* transmit overrun */
-#define SIXP_RX_ORUN 0x50 /* receive overrun */
-#define SIXP_RX_BUF_OVL 0x58 /* receive buffer overflow */
+#define SIXP_SEOF 0x40 /* start and end of a 6pack frame */
+#define SIXP_TX_URUN 0x48 /* transmit overrun */
+#define SIXP_RX_ORUN 0x50 /* receive overrun */
+#define SIXP_RX_BUF_OVL 0x58 /* receive buffer overflow */
-#define SIXP_CHKSUM 0xFF /* valid checksum of a 6pack frame */
+#define SIXP_CHKSUM 0xFF /* valid checksum of a 6pack frame */
/* masks to get certain bits out of the status bytes sent by the TNC */
@@ -78,23 +79,20 @@
#define SIXP_MTU 256 /* Default MTU */
enum sixpack_flags {
- SIXPF_INUSE, /* Channel in use */
SIXPF_ERROR, /* Parity, etc. error */
};
struct sixpack {
- int magic;
-
/* Various fields. */
- struct tty_struct *tty; /* ptr to TTY structure */
- struct net_device *dev; /* easy for intr handling */
+ struct tty_struct *tty; /* ptr to TTY structure */
+ struct net_device *dev; /* easy for intr handling */
/* These are pointers to the malloc()ed frame buffers. */
- unsigned char *rbuff; /* receiver buffer */
- int rcount; /* received chars counter */
- unsigned char *xbuff; /* transmitter buffer */
- unsigned char *xhead; /* pointer to next byte to XMIT */
- int xleft; /* bytes left in XMIT queue */
+ unsigned char *rbuff; /* receiver buffer */
+ int rcount; /* received chars counter */
+ unsigned char *xbuff; /* transmitter buffer */
+ unsigned char *xhead; /* next byte to XMIT */
+ int xleft; /* bytes left in XMIT queue */
unsigned char raw_buf[4];
unsigned char cooked_buf[400];
@@ -105,11 +103,11 @@
/* 6pack interface statistics. */
struct net_device_stats stats;
- int mtu; /* Our mtu (to spot changes!) */
- int buffsize; /* Max buffers sizes */
+ int mtu; /* Our mtu (to spot changes!) */
+ int buffsize; /* Max buffers sizes */
- unsigned long flags; /* Flag values/ mode etc */
- unsigned char mode; /* 6pack mode */
+ unsigned long flags; /* Flag values/ mode etc */
+ unsigned char mode; /* 6pack mode */
/* 6pack stuff */
unsigned char tx_delay;
@@ -125,112 +123,293 @@
struct timer_list tx_t;
struct timer_list resync_t;
+
+ atomic_t refcnt;
+ struct semaphore dead_sem;
+ spinlock_t lock;
};
#define AX25_6PACK_HEADER_LEN 0
-#define SIXPACK_MAGIC 0x5304
-
-typedef struct sixpack_ctrl {
- struct sixpack ctrl; /* 6pack things */
- struct net_device dev; /* the device */
-} sixpack_ctrl_t;
-static sixpack_ctrl_t **sixpack_ctrls;
-
-int sixpack_maxdev = SIXP_NRUNIT; /* Can be overridden with insmod! */
-MODULE_PARM(sixpack_maxdev, "i");
-MODULE_PARM_DESC(sixpack_maxdev, "number of 6PACK devices");
static void sp_start_tx_timer(struct sixpack *);
-static void sp_xmit_on_air(unsigned long);
-static void resync_tnc(unsigned long);
static void sixpack_decode(struct sixpack *, unsigned char[], int);
static int encode_sixpack(unsigned char *, unsigned char *, int, unsigned char);
static int sixpack_init(struct net_device *dev);
-static void decode_prio_command(unsigned char, struct sixpack *);
-static void decode_std_command(unsigned char, struct sixpack *);
-static void decode_data(unsigned char, struct sixpack *);
+/*
+ * perform the persistence/slottime algorithm for CSMA access. If the
+ * persistence check was successful, write the data to the serial driver.
+ * Note that in case of DAMA operation, the data is not sent here.
+ */
-static int tnc_init(struct sixpack *);
+static void sp_xmit_on_air(unsigned long channel)
+{
+ struct sixpack *sp = (struct sixpack *) channel;
+ int actual;
+ static unsigned char random;
-/* Find a free 6pack channel, and link in this `tty' line. */
-static inline struct sixpack *sp_alloc(void)
+ random = random * 17 + 41;
+
+ if (((sp->status1 & SIXP_DCD_MASK) == 0) && (random < sp->persistence)) {
+ sp->led_state = 0x70;
+ sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
+ sp->tx_enable = 1;
+ actual = sp->tty->driver->write(sp->tty, 0, sp->xbuff, sp->status2);
+ sp->xleft -= actual;
+ sp->xhead += actual;
+ sp->led_state = 0x60;
+ sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
+ sp->status2 = 0;
+ } else
+ sp_start_tx_timer(sp);
+}
+
+/* ----> 6pack timer interrupt handler and friends. <---- */
+static void sp_start_tx_timer(struct sixpack *sp)
+{
+ int when = sp->slottime;
+
+ del_timer(&sp->tx_t);
+ sp->tx_t.data = (unsigned long) sp;
+ sp->tx_t.function = sp_xmit_on_air;
+ sp->tx_t.expires = jiffies + ((when + 1) * HZ) / 100;
+ add_timer(&sp->tx_t);
+}
+
+/* Encapsulate one AX.25 frame and stuff into a TTY queue. */
+static void sp_encaps(struct sixpack *sp, unsigned char *icp, int len)
{
- sixpack_ctrl_t *spp = NULL;
- int i;
+ unsigned char *msg, *p = icp;
+ int actual, count;
- for (i = 0; i < sixpack_maxdev; i++) {
- spp = sixpack_ctrls[i];
+ if (len > sp->mtu) { /* sp->mtu = AX25_MTU = max. PACLEN = 256 */
+ msg = "oversized transmit packet!";
+ goto out_drop;
+ }
- if (spp == NULL)
- break;
+ if (p[0] > 5) {
+ msg = "invalid KISS command";
+ goto out_drop;
+ }
- if (!test_and_set_bit(SIXPF_INUSE, &spp->ctrl.flags))
- break;
+ if ((p[0] != 0) && (len > 2)) {
+ msg = "KISS control packet too long";
+ goto out_drop;
}
- /* Too many devices... */
- if (i >= sixpack_maxdev)
- return NULL;
+ if ((p[0] == 0) && (len < 15)) {
+ msg = "bad AX.25 packet to transmit";
+ goto out_drop;
+ }
- /* If no channels are available, allocate one */
- if (!spp &&
- (sixpack_ctrls[i] = (sixpack_ctrl_t *)kmalloc(sizeof(sixpack_ctrl_t),
- GFP_KERNEL)) != NULL) {
- spp = sixpack_ctrls[i];
+ count = encode_sixpack(p, sp->xbuff, len, sp->tx_delay);
+ set_bit(TTY_DO_WRITE_WAKEUP, &sp->tty->flags);
+
+ switch (p[0]) {
+ case 1: sp->tx_delay = p[1];
+ return;
+ case 2: sp->persistence = p[1];
+ return;
+ case 3: sp->slottime = p[1];
+ return;
+ case 4: /* ignored */
+ return;
+ case 5: sp->duplex = p[1];
+ return;
}
- memset(spp, 0, sizeof(sixpack_ctrl_t));
- /* Initialize channel control data */
- set_bit(SIXPF_INUSE, &spp->ctrl.flags);
- spp->ctrl.tty = NULL;
- sprintf(spp->dev.name, "sp%d", i);
- spp->dev.base_addr = i;
- spp->dev.priv = (void *) &spp->ctrl;
- spp->dev.next = NULL;
- spp->dev.init = sixpack_init;
-
- if (spp != NULL) {
- /* register device so that it can be ifconfig'ed */
- /* sixpack_init() will be called as a side-effect */
- /* SIDE-EFFECT WARNING: sixpack_init() CLEARS spp->ctrl ! */
-
- if (register_netdev(&spp->dev) == 0) {
- set_bit(SIXPF_INUSE, &spp->ctrl.flags);
- spp->ctrl.dev = &spp->dev;
- spp->dev.priv = (void *) &spp->ctrl;
- SET_MODULE_OWNER(&spp->dev);
- return &spp->ctrl;
- } else {
- clear_bit(SIXPF_INUSE, &spp->ctrl.flags);
- printk(KERN_WARNING "sp_alloc() - register_netdev() failure.\n");
- }
+ if (p[0] != 0)
+ return;
+
+ /*
+ * In case of fullduplex or DAMA operation, we don't take care about the
+ * state of the DCD or of any timers, as the determination of the
+ * correct time to send is the job of the AX.25 layer. We send
+ * immediately after data has arrived.
+ */
+ if (sp->duplex == 1) {
+ sp->led_state = 0x70;
+ sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
+ sp->tx_enable = 1;
+ actual = sp->tty->driver->write(sp->tty, 0, sp->xbuff, count);
+ sp->xleft = count - actual;
+ sp->xhead = sp->xbuff + actual;
+ sp->led_state = 0x60;
+ sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
+ } else {
+ sp->xleft = count;
+ sp->xhead = sp->xbuff;
+ sp->status2 = count;
+ if (sp->duplex == 0)
+ sp_start_tx_timer(sp);
}
- return NULL;
+ return;
+
+out_drop:
+ sp->stats.tx_dropped++;
+ netif_start_queue(sp->dev);
+ printk(KERN_DEBUG "%s: %s - dropped.\n", sp->dev->name, msg);
+ return;
+}
+
+/* Encapsulate an IP datagram and kick it into a TTY queue. */
+
+static int sp_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+ struct sixpack *sp = netdev_priv(dev);
+
+ spin_lock_bh(&sp->lock);
+ /* We were not busy, so we are now... :-) */
+ netif_stop_queue(dev);
+ sp->stats.tx_bytes += skb->len;
+ sp_encaps(sp, skb->data, skb->len);
+ spin_unlock_bh(&sp->lock);
+
+ dev_kfree_skb(skb);
+
+ return 0;
+}
+
+static int sp_open_dev(struct net_device *dev)
+{
+ struct sixpack *sp = netdev_priv(dev);
+
+ if (sp->tty == NULL)
+ return -ENODEV;
+ return 0;
+}
+
+/* Close the low-level part of the 6pack channel. */
+static int sp_close(struct net_device *dev)
+{
+ struct sixpack *sp = netdev_priv(dev);
+
+ spin_lock_bh(&sp->lock);
+ if (sp->tty) {
+ /* TTY discipline is running. */
+ clear_bit(TTY_DO_WRITE_WAKEUP, &sp->tty->flags);
+ }
+ netif_stop_queue(dev);
+ spin_unlock_bh(&sp->lock);
+
+ return 0;
+}
+
+/* Return the frame type ID */
+static int sp_header(struct sk_buff *skb, struct net_device *dev,
+ unsigned short type, void *daddr, void *saddr, unsigned len)
+{
+#ifdef CONFIG_INET
+ if (type != htons(ETH_P_AX25))
+ return ax25_encapsulate(skb, dev, type, daddr, saddr, len);
+#endif
+ return 0;
+}
+
+static struct net_device_stats *sp_get_stats(struct net_device *dev)
+{
+ struct sixpack *sp = netdev_priv(dev);
+ return &sp->stats;
+}
+
+static int sp_set_dev_mac_address(struct net_device *dev, void *addr)
+{
+ struct sockaddr *sa = addr;
+ memcpy(dev->dev_addr, sa->sa_data, AX25_ADDR_LEN);
+ return 0;
+}
+
+static int sp_rebuild_header(struct sk_buff *skb)
+{
+#ifdef CONFIG_INET
+ return ax25_rebuild_header(skb);
+#else
+ return 0;
+#endif
+}
+
+static void sp_setup(struct net_device *dev)
+{
+ static char ax25_bcast[AX25_ADDR_LEN] =
+ {'Q'<<1,'S'<<1,'T'<<1,' '<<1,' '<<1,' '<<1,'0'<<1};
+ static char ax25_test[AX25_ADDR_LEN] =
+ {'L'<<1,'I'<<1,'N'<<1,'U'<<1,'X'<<1,' '<<1,'1'<<1};
+
+ /* Finish setting up the DEVICE info. */
+ dev->init = sixpack_init;
+ dev->mtu = SIXP_MTU;
+ dev->hard_start_xmit = sp_xmit;
+ dev->open = sp_open_dev;
+ dev->destructor = free_netdev;
+ dev->stop = sp_close;
+ dev->hard_header = sp_header;
+ dev->get_stats = sp_get_stats;
+ dev->set_mac_address = sp_set_dev_mac_address;
+ dev->hard_header_len = AX25_MAX_HEADER_LEN;
+ dev->addr_len = AX25_ADDR_LEN;
+ dev->type = ARPHRD_AX25;
+ dev->tx_queue_len = 10;
+ dev->rebuild_header = sp_rebuild_header;
+ dev->tx_timeout = NULL;
+
+ /* Only activated in AX.25 mode */
+ memcpy(dev->broadcast, ax25_bcast, AX25_ADDR_LEN);
+ memcpy(dev->dev_addr, ax25_test, AX25_ADDR_LEN);
+
+ SET_MODULE_OWNER(dev);
+
+ /* New-style flags. */
+ dev->flags = 0;
}
+/* Find a free 6pack channel, and link in this `tty' line. */
+static inline struct sixpack *sp_alloc(void)
+{
+ struct sixpack *sp = NULL;
+ struct net_device *dev = NULL;
+
+ dev = alloc_netdev(sizeof(struct sixpack), "sp%d", sp_setup);
+ if (!dev)
+ return NULL;
+
+ sp = netdev_priv(dev);
+ sp->dev = dev;
+
+ spin_lock_init(&sp->lock);
+
+ if (register_netdev(dev))
+ goto out_free;
+
+ return sp;
+
+out_free:
+ printk(KERN_WARNING "sp_alloc() - register_netdev() failure.\n");
+
+ free_netdev(dev);
+
+ return NULL;
+}
/* Free a 6pack channel. */
static inline void sp_free(struct sixpack *sp)
{
- /* Free all 6pack frame buffers. */
- if (sp->rbuff)
- kfree(sp->rbuff);
- sp->rbuff = NULL;
- if (sp->xbuff)
- kfree(sp->xbuff);
- sp->xbuff = NULL;
+ void * tmp;
- if (!test_and_clear_bit(SIXPF_INUSE, &sp->flags))
- printk(KERN_WARNING "%s: sp_free for already free unit.\n", sp->dev->name);
+ /* Free all 6pack frame buffers. */
+ if ((tmp = xchg(&sp->rbuff, NULL)) != NULL)
+ kfree(tmp);
+ if ((tmp = xchg(&sp->xbuff, NULL)) != NULL)
+ kfree(tmp);
}
/* Send one completely decapsulated IP datagram to the IP layer. */
-/* This is the routine that sends the received data to the kernel AX.25.
- 'cmd' is the KISS command. For AX.25 data, it is zero. */
+/*
+ * This is the routine that sends the received data to the kernel AX.25.
+ * 'cmd' is the KISS command. For AX.25 data, it is zero.
+ */
static void sp_bump(struct sixpack *sp, char cmd)
{
@@ -238,98 +417,60 @@
int count;
unsigned char *ptr;
- count = sp->rcount+1;
+ count = sp->rcount + 1;
sp->stats.rx_bytes += count;
- if ((skb = dev_alloc_skb(count)) == NULL) {
- printk(KERN_DEBUG "%s: memory squeeze, dropping packet.\n", sp->dev->name);
- sp->stats.rx_dropped++;
- return;
- }
+ if ((skb = dev_alloc_skb(count)) == NULL)
+ goto out_mem;
skb->dev = sp->dev;
ptr = skb_put(skb, count);
*ptr++ = cmd; /* KISS command */
- memcpy(ptr, (sp->cooked_buf)+1, count);
+ memcpy(ptr, sp->cooked_buf + 1, count);
skb->mac.raw = skb->data;
skb->protocol = htons(ETH_P_AX25);
netif_rx(skb);
sp->dev->last_rx = jiffies;
sp->stats.rx_packets++;
+
+ return;
+
+out_mem:
+ sp->stats.rx_dropped++;
}
/* ----------------------------------------------------------------------- */
-/* Encapsulate one AX.25 frame and stuff into a TTY queue. */
-static void sp_encaps(struct sixpack *sp, unsigned char *icp, int len)
+/*
+ * We have a potential race on dereferencing tty->disc_data, because the tty
+ * layer provides no locking at all - thus one cpu could be running
+ * sixpack_receive_buf while another calls sixpack_close, which zeroes
+ * tty->disc_data and frees the memory that sixpack_receive_buf is using. The
+ * best way to fix this is to use a rwlock in the tty struct, but for now we
+ * use a single global rwlock for all ttys in ppp line discipline.
+ */
+static rwlock_t disc_data_lock = RW_LOCK_UNLOCKED;
+
+static struct sixpack *sp_get(struct tty_struct *tty)
{
- unsigned char *p;
- int actual, count;
-
- if (len > sp->mtu) { /* sp->mtu = AX25_MTU = max. PACLEN = 256 */
- printk(KERN_DEBUG "%s: truncating oversized transmit packet!\n", sp->dev->name);
- sp->stats.tx_dropped++;
- netif_start_queue(sp->dev);
- return;
- }
+ struct sixpack *sp;
- p = icp;
+ read_lock(&disc_data_lock);
+ sp = tty->disc_data;
+ if (sp)
+ atomic_inc(&sp->refcnt);
+ read_unlock(&disc_data_lock);
- if (p[0] > 5) {
- printk(KERN_DEBUG "%s: invalid KISS command -- dropped\n", sp->dev->name);
- netif_start_queue(sp->dev);
- return;
- }
-
- if ((p[0] != 0) && (len > 2)) {
- printk(KERN_DEBUG "%s: KISS control packet too long -- dropped\n", sp->dev->name);
- netif_start_queue(sp->dev);
- return;
- }
-
- if ((p[0] == 0) && (len < 15)) {
- printk(KERN_DEBUG "%s: bad AX.25 packet to transmit -- dropped\n", sp->dev->name);
- netif_start_queue(sp->dev);
- sp->stats.tx_dropped++;
- return;
- }
-
- count = encode_sixpack(p, (unsigned char *) sp->xbuff, len, sp->tx_delay);
- sp->tty->flags |= (1 << TTY_DO_WRITE_WAKEUP);
-
- switch (p[0]) {
- case 1: sp->tx_delay = p[1]; return;
- case 2: sp->persistence = p[1]; return;
- case 3: sp->slottime = p[1]; return;
- case 4: /* ignored */ return;
- case 5: sp->duplex = p[1]; return;
- }
+ return sp;
+}
- if (p[0] == 0) {
- /* in case of fullduplex or DAMA operation, we don't take care
- about the state of the DCD or of any timers, as the determination
- of the correct time to send is the job of the AX.25 layer. We send
- immediately after data has arrived. */
- if (sp->duplex == 1) {
- sp->led_state = 0x70;
- sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
- sp->tx_enable = 1;
- actual = sp->tty->driver->write(sp->tty, 0, sp->xbuff, count);
- sp->xleft = count - actual;
- sp->xhead = sp->xbuff + actual;
- sp->led_state = 0x60;
- sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
- } else {
- sp->xleft = count;
- sp->xhead = sp->xbuff;
- sp->status2 = count;
- if (sp->duplex == 0)
- sp_start_tx_timer(sp);
- }
- }
+static void sp_put(struct sixpack *sp)
+{
+ if (atomic_dec_and_test(&sp->refcnt))
+ up(&sp->dead_sem);
}
/*
@@ -338,22 +479,17 @@
*/
static void sixpack_write_wakeup(struct tty_struct *tty)
{
+ struct sixpack *sp = sp_get(tty);
int actual;
- struct sixpack *sp = (struct sixpack *) tty->disc_data;
-
- /* First make sure we're connected. */
- if (!sp || sp->magic != SIXPACK_MAGIC ||
- !netif_running(sp->dev))
- return;
if (sp->xleft <= 0) {
/* Now serial buffer is almost free & we can start
* transmission of another packet */
sp->stats.tx_packets++;
- tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP);
+ clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
sp->tx_enable = 0;
netif_wake_queue(sp->dev);
- return;
+ goto out;
}
if (sp->tx_enable == 1) {
@@ -361,79 +497,34 @@
sp->xleft -= actual;
sp->xhead += actual;
}
-}
-
-/* ----------------------------------------------------------------------- */
-
-/* Encapsulate an IP datagram and kick it into a TTY queue. */
-
-static int sp_xmit(struct sk_buff *skb, struct net_device *dev)
-{
- struct sixpack *sp = (struct sixpack *) dev->priv;
- /* We were not busy, so we are now... :-) */
- netif_stop_queue(dev);
- sp->stats.tx_bytes += skb->len;
- sp_encaps(sp, skb->data, skb->len);
- dev_kfree_skb(skb);
- return 0;
+out:
+ sp_put(sp);
}
+/* ----------------------------------------------------------------------- */
-/* perform the persistence/slottime algorithm for CSMA access. If the persistence
- check was successful, write the data to the serial driver. Note that in case
- of DAMA operation, the data is not sent here. */
-
-static void sp_xmit_on_air(unsigned long channel)
-{
- struct sixpack *sp = (struct sixpack *) channel;
- int actual;
- static unsigned char random;
-
- random = random * 17 + 41;
-
- if (((sp->status1 & SIXP_DCD_MASK) == 0) && (random < sp->persistence)) {
- sp->led_state = 0x70;
- sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
- sp->tx_enable = 1;
- actual = sp->tty->driver->write(sp->tty, 0, sp->xbuff, sp->status2);
- sp->xleft -= actual;
- sp->xhead += actual;
- sp->led_state = 0x60;
- sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
- sp->status2 = 0;
- } else
- sp_start_tx_timer(sp);
-}
-
-
-/* Return the frame type ID */
-static int sp_header(struct sk_buff *skb, struct net_device *dev, unsigned short type,
- void *daddr, void *saddr, unsigned len)
+/* Open the low-level part of the 6pack channel. */
+static int sp_open(struct net_device *dev)
{
-#ifdef CONFIG_INET
- if (type != htons(ETH_P_AX25))
- return ax25_encapsulate(skb, dev, type, daddr, saddr, len);
-#endif
- return 0;
-}
+ struct sixpack *sp = netdev_priv(dev);
+ char *rbuff, *xbuff = NULL;
+ int err = -ENOBUFS;
+ unsigned long len;
+ /* !!! length of the buffers. MTU is IP MTU, not PACLEN! */
-static int sp_rebuild_header(struct sk_buff *skb)
-{
-#ifdef CONFIG_INET
- return ax25_rebuild_header(skb);
-#else
- return 0;
-#endif
-}
+ len = dev->mtu * 2;
+ rbuff = kmalloc(len + 4, GFP_KERNEL);
+ if (rbuff == NULL)
+ goto err_exit;
+
+ xbuff = kmalloc(len + 4, GFP_KERNEL);
+ if (xbuff == NULL)
+ goto err_exit;
-/* Open the low-level part of the 6pack channel. */
-static int sp_open(struct net_device *dev)
-{
- struct sixpack *sp = (struct sixpack *) dev->priv;
- unsigned long len;
+ spin_lock_bh(&sp->lock);
if (sp->tty == NULL)
return -ENODEV;
@@ -445,18 +536,8 @@
* xbuff Transmit buffer.
*/
- /* !!! length of the buffers. MTU is IP MTU, not PACLEN!
- */
-
- len = dev->mtu * 2;
-
- if ((sp->rbuff = kmalloc(len + 4, GFP_KERNEL)) == NULL)
- return -ENOMEM;
-
- if ((sp->xbuff = kmalloc(len + 4, GFP_KERNEL)) == NULL) {
- kfree(sp->rbuff);
- return -ENOMEM;
- }
+ rbuff = xchg(&sp->rbuff, rbuff);
+ xbuff = xchg(&sp->xbuff, xbuff);
sp->mtu = AX25_MTU + 73;
sp->buffsize = len;
@@ -465,7 +546,7 @@
sp->rx_count_cooked = 0;
sp->xleft = 0;
- sp->flags &= (1 << SIXPF_INUSE); /* Clear ESCAPE & ERROR flags */
+ sp->flags = 0; /* Clear ESCAPE & ERROR flags */
sp->duplex = 0;
sp->tx_delay = SIXP_TXDELAY;
@@ -482,49 +563,47 @@
init_timer(&sp->tx_t);
init_timer(&sp->resync_t);
- return 0;
-}
-
-/* Close the low-level part of the 6pack channel. */
-static int sp_close(struct net_device *dev)
-{
- struct sixpack *sp = (struct sixpack *) dev->priv;
+ spin_unlock_bh(&sp->lock);
- if (sp->tty == NULL)
- return -EBUSY;
+ err = 0;
- sp->tty->flags &= ~(1 << TTY_DO_WRITE_WAKEUP);
+err_exit:
+ if (xbuff)
+ kfree(xbuff);
+ if (rbuff)
+ kfree(rbuff);
- netif_stop_queue(dev);
- return 0;
+ return err;
}
+
static int sixpack_receive_room(struct tty_struct *tty)
{
return 65536; /* We can handle an infinite amount of data. :-) */
}
-/* !!! receive state machine */
-
/*
* Handle the 'receiver data ready' interrupt.
* This function is called by the 'tty_io' module in the kernel when
* a block of 6pack data has been received, which can now be decapsulated
* and sent on to some IP layer for further processing.
*/
-static void sixpack_receive_buf(struct tty_struct *tty, const unsigned char *cp, char *fp, int count)
+static void sixpack_receive_buf(struct tty_struct *tty,
+ const unsigned char *cp, char *fp, int count)
{
+ struct sixpack *sp;
unsigned char buf[512];
int count1;
- struct sixpack *sp = (struct sixpack *) tty->disc_data;
+ if (!count)
+ return;
- if (!sp || sp->magic != SIXPACK_MAGIC ||
- !netif_running(sp->dev) || !count)
+ sp = sp_get(tty);
+ if (!sp)
return;
- memcpy(buf, cp, count<sizeof(buf)? count:sizeof(buf));
+ memcpy(buf, cp, count < sizeof(buf) ? count : sizeof(buf));
/* Read the characters out of the buffer */
@@ -538,6 +617,67 @@
}
}
sixpack_decode(sp, buf, count1);
+
+ sp_put(sp);
+ if (test_and_clear_bit(TTY_THROTTLED, &tty->flags)
+ && tty->driver->unthrottle)
+ tty->driver->unthrottle(tty);
+}
+
+/*
+ * Try to resync the TNC. Called by the resync timer defined in
+ * decode_prio_command
+ */
+
+static void resync_tnc(unsigned long channel)
+{
+ struct sixpack *sp = (struct sixpack *) channel;
+ struct net_device *dev = sp->dev;
+ static char resync_cmd = 0xe8;
+
+ printk(KERN_INFO "%s: resyncing TNC\n", dev->name);
+
+ /* clear any data that might have been received */
+
+ sp->rx_count = 0;
+ sp->rx_count_cooked = 0;
+
+ /* reset state machine */
+
+ sp->status = 1;
+ sp->status1 = 1;
+ sp->status2 = 0;
+ sp->tnc_ok = 0;
+
+ /* resync the TNC */
+
+ sp->led_state = 0x60;
+ sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
+ sp->tty->driver->write(sp->tty, 0, &resync_cmd, 1);
+
+
+ /* Start resync timer again -- the TNC might be still absent */
+
+ del_timer(&sp->resync_t);
+ sp->resync_t.data = (unsigned long) sp;
+ sp->resync_t.function = resync_tnc;
+ sp->resync_t.expires = jiffies + SIXP_RESYNC_TIMEOUT;
+ add_timer(&sp->resync_t);
+}
+
+static inline int tnc_init(struct sixpack *sp)
+{
+ unsigned char inbyte = 0xe8;
+
+ sp->tty->driver->write(sp->tty, 0, &inbyte, 1);
+
+ del_timer(&sp->resync_t);
+ sp->resync_t.data = (unsigned long) sp;
+ sp->resync_t.function = resync_tnc;
+ sp->resync_t.expires = jiffies + SIXP_RESYNC_TIMEOUT;
+ add_timer(&sp->resync_t);
+
+ return 0;
}
/*
@@ -549,37 +689,33 @@
*/
static int sixpack_open(struct tty_struct *tty)
{
- struct sixpack *sp = (struct sixpack *) tty->disc_data;
- int err;
+ struct sixpack *sp;
+ int err = 0;
- /* First make sure we're not already connected. */
+ if (!capable(CAP_NET_ADMIN))
+ return -EPERM;
- if (sp && sp->magic == SIXPACK_MAGIC)
- return -EEXIST;
+ sp = sp_alloc();
+ if (!sp) {
+ err = -ENOMEM;
+ goto out;
+ }
- /* OK. Find a free 6pack channel to use. */
- if ((sp = sp_alloc()) == NULL)
- return -ENFILE;
sp->tty = tty;
- tty->disc_data = sp;
- if (tty->driver->flush_buffer)
- tty->driver->flush_buffer(tty);
-
- if (tty->ldisc.flush_buffer)
- tty->ldisc.flush_buffer(tty);
-
- /* Restore default settings */
- sp->dev->type = ARPHRD_AX25;
+ atomic_set(&sp->refcnt, 1);
+ init_MUTEX_LOCKED(&sp->dead_sem);
/* Perform the low-level 6pack initialization. */
if ((err = sp_open(sp->dev)))
- return err;
+ goto out;
/* Done. We have linked the TTY line to a channel. */
+ tty->disc_data = sp;
tnc_init(sp);
- return sp->dev->base_addr;
+out:
+ return err;
}
@@ -593,102 +729,93 @@
{
struct sixpack *sp = (struct sixpack *) tty->disc_data;
- /* First make sure we're connected. */
- if (!sp || sp->magic != SIXPACK_MAGIC)
+ write_lock(&disc_data_lock);
+ sp = tty->disc_data;
+ tty->disc_data = 0;
+ write_unlock(&disc_data_lock);
+ if (sp == 0)
return;
- rtnl_lock();
- dev_close(sp->dev);
+ /*
+ * We have now ensured that nobody can start using ap from now on, but
+ * we have to wait for all existing users to finish.
+ */
+ if (!atomic_dec_and_test(&sp->refcnt))
+ down(&sp->dead_sem);
del_timer(&sp->tx_t);
del_timer(&sp->resync_t);
- tty->disc_data = 0;
- sp->tty = NULL;
-
sp_free(sp);
- unregister_netdevice(sp->dev);
- rtnl_unlock();
-}
-
-
-static struct net_device_stats *sp_get_stats(struct net_device *dev)
-{
- struct sixpack *sp = (struct sixpack *) dev->priv;
- return &sp->stats;
+ unregister_netdev(sp->dev);
}
-
static int sp_set_mac_address(struct net_device *dev, void *addr)
{
return copy_from_user(dev->dev_addr, addr, AX25_ADDR_LEN) ? -EFAULT : 0;
}
-static int sp_set_dev_mac_address(struct net_device *dev, void *addr)
-{
- struct sockaddr *sa = addr;
- memcpy(dev->dev_addr, sa->sa_data, AX25_ADDR_LEN);
- return 0;
-}
-
-
/* Perform I/O control on an active 6pack channel. */
-static int sixpack_ioctl(struct tty_struct *tty, void *file, int cmd, void *arg)
+static int sixpack_ioctl(struct tty_struct *tty, struct file *file,
+ unsigned int cmd, unsigned long arg)
{
- struct sixpack *sp = (struct sixpack *) tty->disc_data;
- unsigned int tmp;
+ struct sixpack *sp = sp_get(tty);
+ unsigned int tmp, err;
- /* First make sure we're connected. */
- if (!sp || sp->magic != SIXPACK_MAGIC)
- return -EINVAL;
+ if (!sp)
+ return -ENXIO;
switch(cmd) {
case SIOCGIFNAME:
- return copy_to_user(arg, sp->dev->name, strlen(sp->dev->name) + 1) ? -EFAULT : 0;
+ err = copy_to_user((void *) arg, sp->dev->name,
+ strlen(sp->dev->name) + 1) ? -EFAULT : 0;
+ break;
case SIOCGIFENCAP:
- return put_user(0, (int *)arg);
+ err = put_user(0, (int *)arg);
+ break;
case SIOCSIFENCAP:
- if (get_user(tmp, (int *) arg))
- return -EFAULT;
+ if (get_user(tmp, (int *) arg)) {
+ err = -EFAULT;
+ break;
+ }
sp->mode = tmp;
sp->dev->addr_len = AX25_ADDR_LEN; /* sizeof an AX.25 addr */
sp->dev->hard_header_len = AX25_KISS_HEADER_LEN + AX25_MAX_HEADER_LEN + 3;
sp->dev->type = ARPHRD_AX25;
- return 0;
+ err = 0;
+ break;
case SIOCSIFHWADDR:
- return sp_set_mac_address(sp->dev, arg);
+ err = sp_set_mac_address(sp->dev, (void *) arg);
+ break;
/* Allow stty to read, but not set, the serial port */
case TCGETS:
case TCGETA:
- return n_tty_ioctl(tty, (struct file *) file, cmd, (unsigned long) arg);
+ err = n_tty_ioctl(tty, (struct file *) file, cmd, arg);
+ break;
default:
return -ENOIOCTLCMD;
}
-}
-static int sp_open_dev(struct net_device *dev)
-{
- struct sixpack *sp = (struct sixpack *) dev->priv;
- if (sp->tty == NULL)
- return -ENODEV;
- return 0;
+ sp_put(sp);
+
+ return err;
}
/* Fill in our line protocol discipline */
static struct tty_ldisc sp_ldisc = {
- .magic = TTY_LDISC_MAGIC,
+ .owner = THIS_MODULE,
+ .magic = TTY_LDISC_MAGIC,
.name = "6pack",
.open = sixpack_open,
- .close = sixpack_close,
- .ioctl = (int (*)(struct tty_struct *, struct file *,
- unsigned int, unsigned long)) sixpack_ioctl,
+ .close = sixpack_close,
+ .ioctl = sixpack_ioctl,
.receive_buf = sixpack_receive_buf,
.receive_room = sixpack_receive_room,
.write_wakeup = sixpack_write_wakeup,
@@ -696,34 +823,18 @@
/* Initialize 6pack control device -- register 6pack line discipline */
-static char msg_banner[] __initdata = KERN_INFO "AX.25: 6pack driver, " SIXPACK_VERSION " (dynamic channels, max=%d)\n";
-static char msg_nomem[] __initdata = KERN_ERR "6pack: can't allocate sixpack_ctrls[] array! No 6pack available.\n";
+static char msg_banner[] __initdata = KERN_INFO "AX.25: 6pack driver, " SIXPACK_VERSION "\n";
static char msg_regfail[] __initdata = KERN_ERR "6pack: can't register line discipline (err = %d)\n";
static int __init sixpack_init_driver(void)
{
int status;
- /* Do sanity checks on maximum device parameter. */
- if (sixpack_maxdev < 4)
- sixpack_maxdev = 4;
-
- printk(msg_banner, sixpack_maxdev);
-
- sixpack_ctrls = (sixpack_ctrl_t **) kmalloc(sizeof(void*)*sixpack_maxdev, GFP_KERNEL);
- if (sixpack_ctrls == NULL) {
- printk(msg_nomem);
- return -ENOMEM;
- }
-
- /* Clear the pointer array, we allocate devices when we need them */
- memset(sixpack_ctrls, 0, sizeof(void*)*sixpack_maxdev); /* Pointers */
+ printk(msg_banner);
/* Register the provided line protocol discipline */
- if ((status = tty_register_ldisc(N_6PACK, &sp_ldisc)) != 0) {
+ if ((status = tty_register_ldisc(N_6PACK, &sp_ldisc)) != 0)
printk(msg_regfail, status);
- kfree(sixpack_ctrls);
- }
return status;
}
@@ -732,36 +843,16 @@
static void __exit sixpack_exit_driver(void)
{
- int i;
-
- if ((i = tty_register_ldisc(N_6PACK, NULL)))
- printk(msg_unregfail, i);
+ int ret;
- for (i = 0; i < sixpack_maxdev; i++) {
- if (sixpack_ctrls[i]) {
- /*
- * VSV = if dev->start==0, then device
- * unregistered while close proc.
- */
- if (netif_running(&sixpack_ctrls[i]->dev))
- unregister_netdev(&sixpack_ctrls[i]->dev);
-
- kfree(sixpack_ctrls[i]);
- }
- }
- kfree(sixpack_ctrls);
+ if ((ret = tty_register_ldisc(N_6PACK, NULL)))
+ printk(msg_unregfail, ret);
}
-
/* Initialize the 6pack driver. Called by DDI. */
static int sixpack_init(struct net_device *dev)
{
- struct sixpack *sp = (struct sixpack *) dev->priv;
-
- static char ax25_bcast[AX25_ADDR_LEN] =
- {'Q'<<1,'S'<<1,'T'<<1,' '<<1,' '<<1,' '<<1,'0'<<1};
- static char ax25_test[AX25_ADDR_LEN] =
- {'L'<<1,'I'<<1,'N'<<1,'U'<<1,'X'<<1,' '<<1,'1'<<1};
+ struct sixpack *sp = netdev_priv(dev);
if (sp == NULL) /* Allocation failed ?? */
return -ENODEV;
@@ -769,52 +860,15 @@
/* Set up the "6pack Control Block". (And clear statistics) */
memset(sp, 0, sizeof (struct sixpack));
- sp->magic = SIXPACK_MAGIC;
sp->dev = dev;
- /* Finish setting up the DEVICE info. */
- dev->mtu = SIXP_MTU;
- dev->hard_start_xmit = sp_xmit;
- dev->open = sp_open_dev;
- dev->stop = sp_close;
- dev->hard_header = sp_header;
- dev->get_stats = sp_get_stats;
- dev->set_mac_address = sp_set_dev_mac_address;
- dev->hard_header_len = AX25_MAX_HEADER_LEN;
- dev->addr_len = AX25_ADDR_LEN;
- dev->type = ARPHRD_AX25;
- dev->tx_queue_len = 10;
- dev->rebuild_header = sp_rebuild_header;
- dev->tx_timeout = NULL;
-
- memcpy(dev->broadcast, ax25_bcast, AX25_ADDR_LEN); /* Only activated in AX.25 mode */
- memcpy(dev->dev_addr, ax25_test, AX25_ADDR_LEN); /* "" "" "" "" */
-
- /* New-style flags. */
- dev->flags = 0;
-
return 0;
}
-
-
-
-/* ----> 6pack timer interrupt handler and friends. <---- */
-static void sp_start_tx_timer(struct sixpack *sp)
-{
- int when = sp->slottime;
-
- del_timer(&sp->tx_t);
- sp->tx_t.data = (unsigned long) sp;
- sp->tx_t.function = sp_xmit_on_air;
- sp->tx_t.expires = jiffies + ((when+1)*HZ)/100;
- add_timer(&sp->tx_t);
-}
-
-
/* encode an AX.25 packet into 6pack */
-static int encode_sixpack(unsigned char *tx_buf, unsigned char *tx_buf_raw, int length, unsigned char tx_delay)
+static int encode_sixpack(unsigned char *tx_buf, unsigned char *tx_buf_raw,
+ int length, unsigned char tx_delay)
{
int count = 0;
unsigned char checksum = 0, buf[400];
@@ -849,47 +903,28 @@
return raw_count;
}
+/* decode 4 sixpack-encoded bytes into 3 data bytes */
-/* decode a 6pack packet */
-
-static void
-sixpack_decode(struct sixpack *sp, unsigned char pre_rbuff[], int count)
-{
- unsigned char inbyte;
- int count1;
-
- for (count1 = 0; count1 < count; count1++) {
- inbyte = pre_rbuff[count1];
- if (inbyte == SIXP_FOUND_TNC) {
- printk(KERN_INFO "6pack: TNC found.\n");
- sp->tnc_ok = 1;
- del_timer(&sp->resync_t);
- }
- if ((inbyte & SIXP_PRIO_CMD_MASK) != 0)
- decode_prio_command(inbyte, sp);
- else if ((inbyte & SIXP_STD_CMD_MASK) != 0)
- decode_std_command(inbyte, sp);
- else if ((sp->status & SIXP_RX_DCD_MASK) == SIXP_RX_DCD_MASK)
- decode_data(inbyte, sp);
- }
-}
-
-static int tnc_init(struct sixpack *sp)
+static void decode_data(unsigned char inbyte, struct sixpack *sp)
{
- unsigned char inbyte = 0xe8;
+ unsigned char *buf;
- sp->tty->driver->write(sp->tty, 0, &inbyte, 1);
+ if (sp->rx_count != 3) {
+ sp->raw_buf[sp->rx_count++] = inbyte;
- del_timer(&sp->resync_t);
- sp->resync_t.data = (unsigned long) sp;
- sp->resync_t.function = resync_tnc;
- sp->resync_t.expires = jiffies + SIXP_RESYNC_TIMEOUT;
- add_timer(&sp->resync_t);
+ return;
+ }
- return 0;
+ buf = sp->raw_buf;
+ sp->cooked_buf[sp->rx_count_cooked++] =
+ buf[0] | ((buf[1] << 2) & 0xc0);
+ sp->cooked_buf[sp->rx_count_cooked++] =
+ (buf[1] & 0x0f) | ((buf[2] << 2) & 0xf0);
+ sp->cooked_buf[sp->rx_count_cooked++] =
+ (buf[2] & 0x03) | (inbyte << 2);
+ sp->rx_count = 0;
}
-
/* identify and execute a 6pack priority command byte */
static void decode_prio_command(unsigned char cmd, struct sixpack *sp)
@@ -916,8 +951,7 @@
cmd &= !SIXP_RX_DCD_MASK;
}
sp->status = cmd & SIXP_PRIO_DATA_MASK;
- }
- else { /* output watchdog char if idle */
+ } else { /* output watchdog char if idle */
if ((sp->status2 != 0) && (sp->duplex == 1)) {
sp->led_state = 0x70;
sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
@@ -948,46 +982,6 @@
sp->status1 = cmd & SIXP_PRIO_DATA_MASK;
}
-/* try to resync the TNC. Called by the resync timer defined in
- decode_prio_command */
-
-static void resync_tnc(unsigned long channel)
-{
- static char resync_cmd = 0xe8;
- struct sixpack *sp = (struct sixpack *) channel;
-
- printk(KERN_INFO "6pack: resyncing TNC\n");
-
- /* clear any data that might have been received */
-
- sp->rx_count = 0;
- sp->rx_count_cooked = 0;
-
- /* reset state machine */
-
- sp->status = 1;
- sp->status1 = 1;
- sp->status2 = 0;
- sp->tnc_ok = 0;
-
- /* resync the TNC */
-
- sp->led_state = 0x60;
- sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
- sp->tty->driver->write(sp->tty, 0, &resync_cmd, 1);
-
-
- /* Start resync timer again -- the TNC might be still absent */
-
- del_timer(&sp->resync_t);
- sp->resync_t.data = (unsigned long) sp;
- sp->resync_t.function = resync_tnc;
- sp->resync_t.expires = jiffies + SIXP_RESYNC_TIMEOUT;
- add_timer(&sp->resync_t);
-}
-
-
-
/* identify and execute a standard 6pack command byte */
static void decode_std_command(unsigned char cmd, struct sixpack *sp)
@@ -997,67 +991,70 @@
channel = cmd & SIXP_CHN_MASK;
switch (cmd & SIXP_CMD_MASK) { /* normal command */
- case SIXP_SEOF:
- if ((sp->rx_count == 0) && (sp->rx_count_cooked == 0)) {
- if ((sp->status & SIXP_RX_DCD_MASK) ==
- SIXP_RX_DCD_MASK) {
- sp->led_state = 0x68;
- sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
- }
- } else {
- sp->led_state = 0x60;
- /* fill trailing bytes with zeroes */
+ case SIXP_SEOF:
+ if ((sp->rx_count == 0) && (sp->rx_count_cooked == 0)) {
+ if ((sp->status & SIXP_RX_DCD_MASK) ==
+ SIXP_RX_DCD_MASK) {
+ sp->led_state = 0x68;
sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
- rest = sp->rx_count;
- if (rest != 0)
- for (i = rest; i <= 3; i++)
- decode_data(0, sp);
- if (rest == 2)
- sp->rx_count_cooked -= 2;
- else if (rest == 3)
- sp->rx_count_cooked -= 1;
- for (i = 0; i < sp->rx_count_cooked; i++)
- checksum += sp->cooked_buf[i];
- if (checksum != SIXP_CHKSUM) {
- printk(KERN_DEBUG "6pack: bad checksum %2.2x\n", checksum);
- } else {
- sp->rcount = sp->rx_count_cooked-2;
- sp_bump(sp, 0);
- }
- sp->rx_count_cooked = 0;
}
- break;
- case SIXP_TX_URUN: printk(KERN_DEBUG "6pack: TX underrun\n");
- break;
- case SIXP_RX_ORUN: printk(KERN_DEBUG "6pack: RX overrun\n");
- break;
- case SIXP_RX_BUF_OVL:
- printk(KERN_DEBUG "6pack: RX buffer overflow\n");
+ } else {
+ sp->led_state = 0x60;
+ /* fill trailing bytes with zeroes */
+ sp->tty->driver->write(sp->tty, 0, &sp->led_state, 1);
+ rest = sp->rx_count;
+ if (rest != 0)
+ for (i = rest; i <= 3; i++)
+ decode_data(0, sp);
+ if (rest == 2)
+ sp->rx_count_cooked -= 2;
+ else if (rest == 3)
+ sp->rx_count_cooked -= 1;
+ for (i = 0; i < sp->rx_count_cooked; i++)
+ checksum += sp->cooked_buf[i];
+ if (checksum != SIXP_CHKSUM) {
+ printk(KERN_DEBUG "6pack: bad checksum %2.2x\n", checksum);
+ } else {
+ sp->rcount = sp->rx_count_cooked-2;
+ sp_bump(sp, 0);
+ }
+ sp->rx_count_cooked = 0;
+ }
+ break;
+ case SIXP_TX_URUN: printk(KERN_DEBUG "6pack: TX underrun\n");
+ break;
+ case SIXP_RX_ORUN: printk(KERN_DEBUG "6pack: RX overrun\n");
+ break;
+ case SIXP_RX_BUF_OVL:
+ printk(KERN_DEBUG "6pack: RX buffer overflow\n");
}
}
-/* decode 4 sixpack-encoded bytes into 3 data bytes */
+/* decode a 6pack packet */
-static void decode_data(unsigned char inbyte, struct sixpack *sp)
+static void
+sixpack_decode(struct sixpack *sp, unsigned char pre_rbuff[], int count)
{
- unsigned char *buf;
+ unsigned char inbyte;
+ int count1;
- if (sp->rx_count != 3)
- sp->raw_buf[sp->rx_count++] = inbyte;
- else {
- buf = sp->raw_buf;
- sp->cooked_buf[sp->rx_count_cooked++] =
- buf[0] | ((buf[1] << 2) & 0xc0);
- sp->cooked_buf[sp->rx_count_cooked++] =
- (buf[1] & 0x0f) | ((buf[2] << 2) & 0xf0);
- sp->cooked_buf[sp->rx_count_cooked++] =
- (buf[2] & 0x03) | (inbyte << 2);
- sp->rx_count = 0;
+ for (count1 = 0; count1 < count; count1++) {
+ inbyte = pre_rbuff[count1];
+ if (inbyte == SIXP_FOUND_TNC) {
+ printk(KERN_INFO "6pack: TNC found.\n");
+ sp->tnc_ok = 1;
+ del_timer(&sp->resync_t);
+ }
+ if ((inbyte & SIXP_PRIO_CMD_MASK) != 0)
+ decode_prio_command(inbyte, sp);
+ else if ((inbyte & SIXP_STD_CMD_MASK) != 0)
+ decode_std_command(inbyte, sp);
+ else if ((sp->status & SIXP_RX_DCD_MASK) == SIXP_RX_DCD_MASK)
+ decode_data(inbyte, sp);
}
}
-
-MODULE_AUTHOR("Andreas Könsgen <ajk@ccac.rwth-aachen.de>");
+MODULE_AUTHOR("Ralf Baechle DO1GRB <ralf@linux-mips.org>");
MODULE_DESCRIPTION("6pack driver for AX.25");
MODULE_LICENSE("GPL");
MODULE_ALIAS_LDISC(N_6PACK);
-
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2004-03-15 18:42 [PATCH] 2nd 6pack patch for 2.6.4 Ralf Baechle DO1GRB
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