+++ /dev/null
-// SPDX-License-Identifier: GPL-1.0+
-/* r3964 linediscipline for linux
- *
- * -----------------------------------------------------------
- * Copyright by
- * Philips Automation Projects
- * Kassel (Germany)
- * -----------------------------------------------------------
- * Author:
- * L. Haag
- *
- * $Log: n_r3964.c,v $
- * Revision 1.10 2001/03/18 13:02:24 dwmw2
- * Fix timer usage, use spinlocks properly.
- *
- * Revision 1.9 2001/03/18 12:52:14 dwmw2
- * Merge changes in 2.4.2
- *
- * Revision 1.8 2000/03/23 14:14:54 dwmw2
- * Fix race in sleeping in r3964_read()
- *
- * Revision 1.7 1999/28/08 11:41:50 dwmw2
- * Port to 2.3 kernel
- *
- * Revision 1.6 1998/09/30 00:40:40 dwmw2
- * Fixed compilation on 2.0.x kernels
- * Updated to newly registered tty-ldisc number 9
- *
- * Revision 1.5 1998/09/04 21:57:36 dwmw2
- * Signal handling bug fixes, port to 2.1.x.
- *
- * Revision 1.4 1998/04/02 20:26:59 lhaag
- * select, blocking, ...
- *
- * Revision 1.3 1998/02/12 18:58:43 root
- * fixed some memory leaks
- * calculation of checksum characters
- *
- * Revision 1.2 1998/02/07 13:03:34 root
- * ioctl read_telegram
- *
- * Revision 1.1 1998/02/06 19:21:03 root
- * Initial revision
- *
- *
- */
-
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/sched.h>
-#include <linux/types.h>
-#include <linux/fcntl.h>
-#include <linux/interrupt.h>
-#include <linux/ptrace.h>
-#include <linux/ioport.h>
-#include <linux/in.h>
-#include <linux/slab.h>
-#include <linux/tty.h>
-#include <linux/errno.h>
-#include <linux/string.h> /* used in new tty drivers */
-#include <linux/signal.h> /* used in new tty drivers */
-#include <linux/ioctl.h>
-#include <linux/n_r3964.h>
-#include <linux/poll.h>
-#include <linux/init.h>
-#include <linux/uaccess.h>
-
-/*#define DEBUG_QUEUE*/
-
-/* Log successful handshake and protocol operations */
-/*#define DEBUG_PROTO_S*/
-
-/* Log handshake and protocol errors: */
-/*#define DEBUG_PROTO_E*/
-
-/* Log Linediscipline operations (open, close, read, write...): */
-/*#define DEBUG_LDISC*/
-
-/* Log module and memory operations (init, cleanup; kmalloc, kfree): */
-/*#define DEBUG_MODUL*/
-
-/* Macro helpers for debug output: */
-#define TRACE(format, args...) printk("r3964: " format "\n" , ## args)
-
-#ifdef DEBUG_MODUL
-#define TRACE_M(format, args...) printk("r3964: " format "\n" , ## args)
-#else
-#define TRACE_M(fmt, arg...) do {} while (0)
-#endif
-#ifdef DEBUG_PROTO_S
-#define TRACE_PS(format, args...) printk("r3964: " format "\n" , ## args)
-#else
-#define TRACE_PS(fmt, arg...) do {} while (0)
-#endif
-#ifdef DEBUG_PROTO_E
-#define TRACE_PE(format, args...) printk("r3964: " format "\n" , ## args)
-#else
-#define TRACE_PE(fmt, arg...) do {} while (0)
-#endif
-#ifdef DEBUG_LDISC
-#define TRACE_L(format, args...) printk("r3964: " format "\n" , ## args)
-#else
-#define TRACE_L(fmt, arg...) do {} while (0)
-#endif
-#ifdef DEBUG_QUEUE
-#define TRACE_Q(format, args...) printk("r3964: " format "\n" , ## args)
-#else
-#define TRACE_Q(fmt, arg...) do {} while (0)
-#endif
-static void add_tx_queue(struct r3964_info *, struct r3964_block_header *);
-static void remove_from_tx_queue(struct r3964_info *pInfo, int error_code);
-static void put_char(struct r3964_info *pInfo, unsigned char ch);
-static void trigger_transmit(struct r3964_info *pInfo);
-static void retry_transmit(struct r3964_info *pInfo);
-static void transmit_block(struct r3964_info *pInfo);
-static void receive_char(struct r3964_info *pInfo, const unsigned char c);
-static void receive_error(struct r3964_info *pInfo, const char flag);
-static void on_timeout(struct timer_list *t);
-static int enable_signals(struct r3964_info *pInfo, struct pid *pid, int arg);
-static int read_telegram(struct r3964_info *pInfo, struct pid *pid,
- unsigned char __user * buf);
-static void add_msg(struct r3964_client_info *pClient, int msg_id, int arg,
- int error_code, struct r3964_block_header *pBlock);
-static struct r3964_message *remove_msg(struct r3964_info *pInfo,
- struct r3964_client_info *pClient);
-static void remove_client_block(struct r3964_info *pInfo,
- struct r3964_client_info *pClient);
-
-static int r3964_open(struct tty_struct *tty);
-static void r3964_close(struct tty_struct *tty);
-static ssize_t r3964_read(struct tty_struct *tty, struct file *file,
- void *cookie, unsigned char *buf, size_t nr);
-static ssize_t r3964_write(struct tty_struct *tty, struct file *file,
- const unsigned char *buf, size_t nr);
-static int r3964_ioctl(struct tty_struct *tty, struct file *file,
- unsigned int cmd, unsigned long arg);
-#ifdef CONFIG_COMPAT
-static int r3964_compat_ioctl(struct tty_struct *tty, struct file *file,
- unsigned int cmd, unsigned long arg);
-#endif
-static void r3964_set_termios(struct tty_struct *tty, struct ktermios *old);
-static __poll_t r3964_poll(struct tty_struct *tty, struct file *file,
- struct poll_table_struct *wait);
-static void r3964_receive_buf(struct tty_struct *tty, const unsigned char *cp,
- char *fp, int count);
-
-static struct tty_ldisc_ops tty_ldisc_N_R3964 = {
- .owner = THIS_MODULE,
- .name = "R3964",
- .open = r3964_open,
- .close = r3964_close,
- .read = r3964_read,
- .write = r3964_write,
- .ioctl = r3964_ioctl,
-#ifdef CONFIG_COMPAT
- .compat_ioctl = r3964_compat_ioctl,
-#endif
- .set_termios = r3964_set_termios,
- .poll = r3964_poll,
- .receive_buf = r3964_receive_buf,
-};
-
-static void dump_block(const unsigned char *block, unsigned int length)
-{
- unsigned int i, j;
- char linebuf[16 * 3 + 1];
-
- for (i = 0; i < length; i += 16) {
- for (j = 0; (j < 16) && (j + i < length); j++) {
- sprintf(linebuf + 3 * j, "%02x ", block[i + j]);
- }
- linebuf[3 * j] = '\0';
- TRACE_PS("%s", linebuf);
- }
-}
-
-/*************************************************************
- * Driver initialisation
- *************************************************************/
-
-/*************************************************************
- * Module support routines
- *************************************************************/
-
-static void __exit r3964_exit(void)
-{
- int status;
-
- TRACE_M("cleanup_module()");
-
- status = tty_unregister_ldisc(N_R3964);
-
- if (status != 0) {
- printk(KERN_ERR "r3964: error unregistering linediscipline: "
- "%d\n", status);
- } else {
- TRACE_L("linediscipline successfully unregistered");
- }
-}
-
-static int __init r3964_init(void)
-{
- int status;
-
- printk("r3964: Philips r3964 Driver $Revision: 1.10 $\n");
-
- /*
- * Register the tty line discipline
- */
-
- status = tty_register_ldisc(N_R3964, &tty_ldisc_N_R3964);
- if (status == 0) {
- TRACE_L("line discipline %d registered", N_R3964);
- TRACE_L("flags=%x num=%x", tty_ldisc_N_R3964.flags,
- tty_ldisc_N_R3964.num);
- TRACE_L("open=%p", tty_ldisc_N_R3964.open);
- TRACE_L("tty_ldisc_N_R3964 = %p", &tty_ldisc_N_R3964);
- } else {
- printk(KERN_ERR "r3964: error registering line discipline: "
- "%d\n", status);
- }
- return status;
-}
-
-module_init(r3964_init);
-module_exit(r3964_exit);
-
-/*************************************************************
- * Protocol implementation routines
- *************************************************************/
-
-static void add_tx_queue(struct r3964_info *pInfo,
- struct r3964_block_header *pHeader)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&pInfo->lock, flags);
-
- pHeader->next = NULL;
-
- if (pInfo->tx_last == NULL) {
- pInfo->tx_first = pInfo->tx_last = pHeader;
- } else {
- pInfo->tx_last->next = pHeader;
- pInfo->tx_last = pHeader;
- }
-
- spin_unlock_irqrestore(&pInfo->lock, flags);
-
- TRACE_Q("add_tx_queue %p, length %d, tx_first = %p",
- pHeader, pHeader->length, pInfo->tx_first);
-}
-
-static void remove_from_tx_queue(struct r3964_info *pInfo, int error_code)
-{
- struct r3964_block_header *pHeader;
- unsigned long flags;
-#ifdef DEBUG_QUEUE
- struct r3964_block_header *pDump;
-#endif
-
- pHeader = pInfo->tx_first;
-
- if (pHeader == NULL)
- return;
-
-#ifdef DEBUG_QUEUE
- printk("r3964: remove_from_tx_queue: %p, length %u - ",
- pHeader, pHeader->length);
- for (pDump = pHeader; pDump; pDump = pDump->next)
- printk("%p ", pDump);
- printk("\n");
-#endif
-
- if (pHeader->owner) {
- if (error_code) {
- add_msg(pHeader->owner, R3964_MSG_ACK, 0,
- error_code, NULL);
- } else {
- add_msg(pHeader->owner, R3964_MSG_ACK, pHeader->length,
- error_code, NULL);
- }
- wake_up_interruptible(&pInfo->tty->read_wait);
- }
-
- spin_lock_irqsave(&pInfo->lock, flags);
-
- pInfo->tx_first = pHeader->next;
- if (pInfo->tx_first == NULL) {
- pInfo->tx_last = NULL;
- }
-
- spin_unlock_irqrestore(&pInfo->lock, flags);
-
- kfree(pHeader);
- TRACE_M("remove_from_tx_queue - kfree %p", pHeader);
-
- TRACE_Q("remove_from_tx_queue: tx_first = %p, tx_last = %p",
- pInfo->tx_first, pInfo->tx_last);
-}
-
-static void add_rx_queue(struct r3964_info *pInfo,
- struct r3964_block_header *pHeader)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&pInfo->lock, flags);
-
- pHeader->next = NULL;
-
- if (pInfo->rx_last == NULL) {
- pInfo->rx_first = pInfo->rx_last = pHeader;
- } else {
- pInfo->rx_last->next = pHeader;
- pInfo->rx_last = pHeader;
- }
- pInfo->blocks_in_rx_queue++;
-
- spin_unlock_irqrestore(&pInfo->lock, flags);
-
- TRACE_Q("add_rx_queue: %p, length = %d, rx_first = %p, count = %d",
- pHeader, pHeader->length,
- pInfo->rx_first, pInfo->blocks_in_rx_queue);
-}
-
-static void remove_from_rx_queue(struct r3964_info *pInfo,
- struct r3964_block_header *pHeader)
-{
- unsigned long flags;
- struct r3964_block_header *pFind;
-
- if (pHeader == NULL)
- return;
-
- TRACE_Q("remove_from_rx_queue: rx_first = %p, rx_last = %p, count = %d",
- pInfo->rx_first, pInfo->rx_last, pInfo->blocks_in_rx_queue);
- TRACE_Q("remove_from_rx_queue: %p, length %u",
- pHeader, pHeader->length);
-
- spin_lock_irqsave(&pInfo->lock, flags);
-
- if (pInfo->rx_first == pHeader) {
- /* Remove the first block in the linked list: */
- pInfo->rx_first = pHeader->next;
-
- if (pInfo->rx_first == NULL) {
- pInfo->rx_last = NULL;
- }
- pInfo->blocks_in_rx_queue--;
- } else {
- /* Find block to remove: */
- for (pFind = pInfo->rx_first; pFind; pFind = pFind->next) {
- if (pFind->next == pHeader) {
- /* Got it. */
- pFind->next = pHeader->next;
- pInfo->blocks_in_rx_queue--;
- if (pFind->next == NULL) {
- /* Oh, removed the last one! */
- pInfo->rx_last = pFind;
- }
- break;
- }
- }
- }
-
- spin_unlock_irqrestore(&pInfo->lock, flags);
-
- kfree(pHeader);
- TRACE_M("remove_from_rx_queue - kfree %p", pHeader);
-
- TRACE_Q("remove_from_rx_queue: rx_first = %p, rx_last = %p, count = %d",
- pInfo->rx_first, pInfo->rx_last, pInfo->blocks_in_rx_queue);
-}
-
-static void put_char(struct r3964_info *pInfo, unsigned char ch)
-{
- struct tty_struct *tty = pInfo->tty;
- /* FIXME: put_char should not be called from an IRQ */
- tty_put_char(tty, ch);
- pInfo->bcc ^= ch;
-}
-
-static void flush(struct r3964_info *pInfo)
-{
- struct tty_struct *tty = pInfo->tty;
-
- if (tty == NULL || tty->ops->flush_chars == NULL)
- return;
- tty->ops->flush_chars(tty);
-}
-
-static void trigger_transmit(struct r3964_info *pInfo)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&pInfo->lock, flags);
-
- if ((pInfo->state == R3964_IDLE) && (pInfo->tx_first != NULL)) {
- pInfo->state = R3964_TX_REQUEST;
- pInfo->nRetry = 0;
- pInfo->flags &= ~R3964_ERROR;
- mod_timer(&pInfo->tmr, jiffies + R3964_TO_QVZ);
-
- spin_unlock_irqrestore(&pInfo->lock, flags);
-
- TRACE_PS("trigger_transmit - sent STX");
-
- put_char(pInfo, STX);
- flush(pInfo);
-
- pInfo->bcc = 0;
- } else {
- spin_unlock_irqrestore(&pInfo->lock, flags);
- }
-}
-
-static void retry_transmit(struct r3964_info *pInfo)
-{
- if (pInfo->nRetry < R3964_MAX_RETRIES) {
- TRACE_PE("transmission failed. Retry #%d", pInfo->nRetry);
- pInfo->bcc = 0;
- put_char(pInfo, STX);
- flush(pInfo);
- pInfo->state = R3964_TX_REQUEST;
- pInfo->nRetry++;
- mod_timer(&pInfo->tmr, jiffies + R3964_TO_QVZ);
- } else {
- TRACE_PE("transmission failed after %d retries",
- R3964_MAX_RETRIES);
-
- remove_from_tx_queue(pInfo, R3964_TX_FAIL);
-
- put_char(pInfo, NAK);
- flush(pInfo);
- pInfo->state = R3964_IDLE;
-
- trigger_transmit(pInfo);
- }
-}
-
-static void transmit_block(struct r3964_info *pInfo)
-{
- struct tty_struct *tty = pInfo->tty;
- struct r3964_block_header *pBlock = pInfo->tx_first;
- int room = 0;
-
- if (tty == NULL || pBlock == NULL) {
- return;
- }
-
- room = tty_write_room(tty);
-
- TRACE_PS("transmit_block %p, room %d, length %d",
- pBlock, room, pBlock->length);
-
- while (pInfo->tx_position < pBlock->length) {
- if (room < 2)
- break;
-
- if (pBlock->data[pInfo->tx_position] == DLE) {
- /* send additional DLE char: */
- put_char(pInfo, DLE);
- }
- put_char(pInfo, pBlock->data[pInfo->tx_position++]);
-
- room--;
- }
-
- if ((pInfo->tx_position == pBlock->length) && (room >= 3)) {
- put_char(pInfo, DLE);
- put_char(pInfo, ETX);
- if (pInfo->flags & R3964_BCC) {
- put_char(pInfo, pInfo->bcc);
- }
- pInfo->state = R3964_WAIT_FOR_TX_ACK;
- mod_timer(&pInfo->tmr, jiffies + R3964_TO_QVZ);
- }
- flush(pInfo);
-}
-
-static void on_receive_block(struct r3964_info *pInfo)
-{
- unsigned int length;
- struct r3964_client_info *pClient;
- struct r3964_block_header *pBlock;
-
- length = pInfo->rx_position;
-
- /* compare byte checksum characters: */
- if (pInfo->flags & R3964_BCC) {
- if (pInfo->bcc != pInfo->last_rx) {
- TRACE_PE("checksum error - got %x but expected %x",
- pInfo->last_rx, pInfo->bcc);
- pInfo->flags |= R3964_CHECKSUM;
- }
- }
-
- /* check for errors (parity, overrun,...): */
- if (pInfo->flags & R3964_ERROR) {
- TRACE_PE("on_receive_block - transmission failed error %x",
- pInfo->flags & R3964_ERROR);
-
- put_char(pInfo, NAK);
- flush(pInfo);
- if (pInfo->nRetry < R3964_MAX_RETRIES) {
- pInfo->state = R3964_WAIT_FOR_RX_REPEAT;
- pInfo->nRetry++;
- mod_timer(&pInfo->tmr, jiffies + R3964_TO_RX_PANIC);
- } else {
- TRACE_PE("on_receive_block - failed after max retries");
- pInfo->state = R3964_IDLE;
- }
- return;
- }
-
- /* received block; submit DLE: */
- put_char(pInfo, DLE);
- flush(pInfo);
- del_timer_sync(&pInfo->tmr);
- TRACE_PS(" rx success: got %d chars", length);
-
- /* prepare struct r3964_block_header: */
- pBlock = kmalloc(length + sizeof(struct r3964_block_header),
- GFP_KERNEL);
- TRACE_M("on_receive_block - kmalloc %p", pBlock);
-
- if (pBlock == NULL)
- return;
-
- pBlock->length = length;
- pBlock->data = ((unsigned char *)pBlock) +
- sizeof(struct r3964_block_header);
- pBlock->locks = 0;
- pBlock->next = NULL;
- pBlock->owner = NULL;
-
- memcpy(pBlock->data, pInfo->rx_buf, length);
-
- /* queue block into rx_queue: */
- add_rx_queue(pInfo, pBlock);
-
- /* notify attached client processes: */
- for (pClient = pInfo->firstClient; pClient; pClient = pClient->next) {
- if (pClient->sig_flags & R3964_SIG_DATA) {
- add_msg(pClient, R3964_MSG_DATA, length, R3964_OK,
- pBlock);
- }
- }
- wake_up_interruptible(&pInfo->tty->read_wait);
-
- pInfo->state = R3964_IDLE;
-
- trigger_transmit(pInfo);
-}
-
-static void receive_char(struct r3964_info *pInfo, const unsigned char c)
-{
- switch (pInfo->state) {
- case R3964_TX_REQUEST:
- if (c == DLE) {
- TRACE_PS("TX_REQUEST - got DLE");
-
- pInfo->state = R3964_TRANSMITTING;
- pInfo->tx_position = 0;
-
- transmit_block(pInfo);
- } else if (c == STX) {
- if (pInfo->nRetry == 0) {
- TRACE_PE("TX_REQUEST - init conflict");
- if (pInfo->priority == R3964_SLAVE) {
- goto start_receiving;
- }
- } else {
- TRACE_PE("TX_REQUEST - secondary init "
- "conflict!? Switching to SLAVE mode "
- "for next rx.");
- goto start_receiving;
- }
- } else {
- TRACE_PE("TX_REQUEST - char != DLE: %x", c);
- retry_transmit(pInfo);
- }
- break;
- case R3964_TRANSMITTING:
- if (c == NAK) {
- TRACE_PE("TRANSMITTING - got NAK");
- retry_transmit(pInfo);
- } else {
- TRACE_PE("TRANSMITTING - got invalid char");
-
- pInfo->state = R3964_WAIT_ZVZ_BEFORE_TX_RETRY;
- mod_timer(&pInfo->tmr, jiffies + R3964_TO_ZVZ);
- }
- break;
- case R3964_WAIT_FOR_TX_ACK:
- if (c == DLE) {
- TRACE_PS("WAIT_FOR_TX_ACK - got DLE");
- remove_from_tx_queue(pInfo, R3964_OK);
-
- pInfo->state = R3964_IDLE;
- trigger_transmit(pInfo);
- } else {
- retry_transmit(pInfo);
- }
- break;
- case R3964_WAIT_FOR_RX_REPEAT:
- case R3964_IDLE:
- if (c == STX) {
- /* Prevent rx_queue from overflow: */
- if (pInfo->blocks_in_rx_queue >=
- R3964_MAX_BLOCKS_IN_RX_QUEUE) {
- TRACE_PE("IDLE - got STX but no space in "
- "rx_queue!");
- pInfo->state = R3964_WAIT_FOR_RX_BUF;
- mod_timer(&pInfo->tmr,
- jiffies + R3964_TO_NO_BUF);
- break;
- }
-start_receiving:
- /* Ok, start receiving: */
- TRACE_PS("IDLE - got STX");
- pInfo->rx_position = 0;
- pInfo->last_rx = 0;
- pInfo->flags &= ~R3964_ERROR;
- pInfo->state = R3964_RECEIVING;
- mod_timer(&pInfo->tmr, jiffies + R3964_TO_ZVZ);
- pInfo->nRetry = 0;
- put_char(pInfo, DLE);
- flush(pInfo);
- pInfo->bcc = 0;
- }
- break;
- case R3964_RECEIVING:
- if (pInfo->rx_position < RX_BUF_SIZE) {
- pInfo->bcc ^= c;
-
- if (c == DLE) {
- if (pInfo->last_rx == DLE) {
- pInfo->last_rx = 0;
- goto char_to_buf;
- }
- pInfo->last_rx = DLE;
- break;
- } else if ((c == ETX) && (pInfo->last_rx == DLE)) {
- if (pInfo->flags & R3964_BCC) {
- pInfo->state = R3964_WAIT_FOR_BCC;
- mod_timer(&pInfo->tmr,
- jiffies + R3964_TO_ZVZ);
- } else {
- on_receive_block(pInfo);
- }
- } else {
- pInfo->last_rx = c;
-char_to_buf:
- pInfo->rx_buf[pInfo->rx_position++] = c;
- mod_timer(&pInfo->tmr, jiffies + R3964_TO_ZVZ);
- }
- }
- /* else: overflow-msg? BUF_SIZE>MTU; should not happen? */
- break;
- case R3964_WAIT_FOR_BCC:
- pInfo->last_rx = c;
- on_receive_block(pInfo);
- break;
- }
-}
-
-static void receive_error(struct r3964_info *pInfo, const char flag)
-{
- switch (flag) {
- case TTY_NORMAL:
- break;
- case TTY_BREAK:
- TRACE_PE("received break");
- pInfo->flags |= R3964_BREAK;
- break;
- case TTY_PARITY:
- TRACE_PE("parity error");
- pInfo->flags |= R3964_PARITY;
- break;
- case TTY_FRAME:
- TRACE_PE("frame error");
- pInfo->flags |= R3964_FRAME;
- break;
- case TTY_OVERRUN:
- TRACE_PE("frame overrun");
- pInfo->flags |= R3964_OVERRUN;
- break;
- default:
- TRACE_PE("receive_error - unknown flag %d", flag);
- pInfo->flags |= R3964_UNKNOWN;
- break;
- }
-}
-
-static void on_timeout(struct timer_list *t)
-{
- struct r3964_info *pInfo = from_timer(pInfo, t, tmr);
-
- switch (pInfo->state) {
- case R3964_TX_REQUEST:
- TRACE_PE("TX_REQUEST - timeout");
- retry_transmit(pInfo);
- break;
- case R3964_WAIT_ZVZ_BEFORE_TX_RETRY:
- put_char(pInfo, NAK);
- flush(pInfo);
- retry_transmit(pInfo);
- break;
- case R3964_WAIT_FOR_TX_ACK:
- TRACE_PE("WAIT_FOR_TX_ACK - timeout");
- retry_transmit(pInfo);
- break;
- case R3964_WAIT_FOR_RX_BUF:
- TRACE_PE("WAIT_FOR_RX_BUF - timeout");
- put_char(pInfo, NAK);
- flush(pInfo);
- pInfo->state = R3964_IDLE;
- break;
- case R3964_RECEIVING:
- TRACE_PE("RECEIVING - timeout after %d chars",
- pInfo->rx_position);
- put_char(pInfo, NAK);
- flush(pInfo);
- pInfo->state = R3964_IDLE;
- break;
- case R3964_WAIT_FOR_RX_REPEAT:
- TRACE_PE("WAIT_FOR_RX_REPEAT - timeout");
- pInfo->state = R3964_IDLE;
- break;
- case R3964_WAIT_FOR_BCC:
- TRACE_PE("WAIT_FOR_BCC - timeout");
- put_char(pInfo, NAK);
- flush(pInfo);
- pInfo->state = R3964_IDLE;
- break;
- }
-}
-
-static struct r3964_client_info *findClient(struct r3964_info *pInfo,
- struct pid *pid)
-{
- struct r3964_client_info *pClient;
-
- for (pClient = pInfo->firstClient; pClient; pClient = pClient->next) {
- if (pClient->pid == pid) {
- return pClient;
- }
- }
- return NULL;
-}
-
-static int enable_signals(struct r3964_info *pInfo, struct pid *pid, int arg)
-{
- struct r3964_client_info *pClient;
- struct r3964_client_info **ppClient;
- struct r3964_message *pMsg;
-
- if ((arg & R3964_SIG_ALL) == 0) {
- /* Remove client from client list */
- for (ppClient = &pInfo->firstClient; *ppClient;
- ppClient = &(*ppClient)->next) {
- pClient = *ppClient;
-
- if (pClient->pid == pid) {
- TRACE_PS("removing client %d from client list",
- pid_nr(pid));
- *ppClient = pClient->next;
- while (pClient->msg_count) {
- pMsg = remove_msg(pInfo, pClient);
- if (pMsg) {
- kfree(pMsg);
- TRACE_M("enable_signals - msg "
- "kfree %p", pMsg);
- }
- }
- put_pid(pClient->pid);
- kfree(pClient);
- TRACE_M("enable_signals - kfree %p", pClient);
- return 0;
- }
- }
- return -EINVAL;
- } else {
- pClient = findClient(pInfo, pid);
- if (pClient) {
- /* update signal options */
- pClient->sig_flags = arg;
- } else {
- /* add client to client list */
- pClient = kmalloc(sizeof(struct r3964_client_info),
- GFP_KERNEL);
- TRACE_M("enable_signals - kmalloc %p", pClient);
- if (pClient == NULL)
- return -ENOMEM;
-
- TRACE_PS("add client %d to client list", pid_nr(pid));
- spin_lock_init(&pClient->lock);
- pClient->sig_flags = arg;
- pClient->pid = get_pid(pid);
- pClient->next = pInfo->firstClient;
- pClient->first_msg = NULL;
- pClient->last_msg = NULL;
- pClient->next_block_to_read = NULL;
- pClient->msg_count = 0;
- pInfo->firstClient = pClient;
- }
- }
-
- return 0;
-}
-
-static int read_telegram(struct r3964_info *pInfo, struct pid *pid,
- unsigned char __user * buf)
-{
- struct r3964_client_info *pClient;
- struct r3964_block_header *block;
-
- if (!buf) {
- return -EINVAL;
- }
-
- pClient = findClient(pInfo, pid);
- if (pClient == NULL) {
- return -EINVAL;
- }
-
- block = pClient->next_block_to_read;
- if (!block) {
- return 0;
- } else {
- if (copy_to_user(buf, block->data, block->length))
- return -EFAULT;
-
- remove_client_block(pInfo, pClient);
- return block->length;
- }
-
- return -EINVAL;
-}
-
-static void add_msg(struct r3964_client_info *pClient, int msg_id, int arg,
- int error_code, struct r3964_block_header *pBlock)
-{
- struct r3964_message *pMsg;
- unsigned long flags;
-
- if (pClient->msg_count < R3964_MAX_MSG_COUNT - 1) {
-queue_the_message:
-
- pMsg = kmalloc(sizeof(struct r3964_message),
- error_code ? GFP_ATOMIC : GFP_KERNEL);
- TRACE_M("add_msg - kmalloc %p", pMsg);
- if (pMsg == NULL) {
- return;
- }
-
- spin_lock_irqsave(&pClient->lock, flags);
-
- pMsg->msg_id = msg_id;
- pMsg->arg = arg;
- pMsg->error_code = error_code;
- pMsg->block = pBlock;
- pMsg->next = NULL;
-
- if (pClient->last_msg == NULL) {
- pClient->first_msg = pClient->last_msg = pMsg;
- } else {
- pClient->last_msg->next = pMsg;
- pClient->last_msg = pMsg;
- }
-
- pClient->msg_count++;
-
- if (pBlock != NULL) {
- pBlock->locks++;
- }
- spin_unlock_irqrestore(&pClient->lock, flags);
- } else {
- if ((pClient->last_msg->msg_id == R3964_MSG_ACK)
- && (pClient->last_msg->error_code == R3964_OVERFLOW)) {
- pClient->last_msg->arg++;
- TRACE_PE("add_msg - inc prev OVERFLOW-msg");
- } else {
- msg_id = R3964_MSG_ACK;
- arg = 0;
- error_code = R3964_OVERFLOW;
- pBlock = NULL;
- TRACE_PE("add_msg - queue OVERFLOW-msg");
- goto queue_the_message;
- }
- }
- /* Send SIGIO signal to client process: */
- if (pClient->sig_flags & R3964_USE_SIGIO) {
- kill_pid(pClient->pid, SIGIO, 1);
- }
-}
-
-static struct r3964_message *remove_msg(struct r3964_info *pInfo,
- struct r3964_client_info *pClient)
-{
- struct r3964_message *pMsg = NULL;
- unsigned long flags;
-
- if (pClient->first_msg) {
- spin_lock_irqsave(&pClient->lock, flags);
-
- pMsg = pClient->first_msg;
- pClient->first_msg = pMsg->next;
- if (pClient->first_msg == NULL) {
- pClient->last_msg = NULL;
- }
-
- pClient->msg_count--;
- if (pMsg->block) {
- remove_client_block(pInfo, pClient);
- pClient->next_block_to_read = pMsg->block;
- }
- spin_unlock_irqrestore(&pClient->lock, flags);
- }
- return pMsg;
-}
-
-static void remove_client_block(struct r3964_info *pInfo,
- struct r3964_client_info *pClient)
-{
- struct r3964_block_header *block;
-
- TRACE_PS("remove_client_block PID %d", pid_nr(pClient->pid));
-
- block = pClient->next_block_to_read;
- if (block) {
- block->locks--;
- if (block->locks == 0) {
- remove_from_rx_queue(pInfo, block);
- }
- }
- pClient->next_block_to_read = NULL;
-}
-
-/*************************************************************
- * Line discipline routines
- *************************************************************/
-
-static int r3964_open(struct tty_struct *tty)
-{
- struct r3964_info *pInfo;
-
- TRACE_L("open");
- TRACE_L("tty=%p, PID=%d, disc_data=%p",
- tty, current->pid, tty->disc_data);
-
- pInfo = kmalloc(sizeof(struct r3964_info), GFP_KERNEL);
- TRACE_M("r3964_open - info kmalloc %p", pInfo);
-
- if (!pInfo) {
- printk(KERN_ERR "r3964: failed to alloc info structure\n");
- return -ENOMEM;
- }
-
- pInfo->rx_buf = kmalloc(RX_BUF_SIZE, GFP_KERNEL);
- TRACE_M("r3964_open - rx_buf kmalloc %p", pInfo->rx_buf);
-
- if (!pInfo->rx_buf) {
- printk(KERN_ERR "r3964: failed to alloc receive buffer\n");
- kfree(pInfo);
- TRACE_M("r3964_open - info kfree %p", pInfo);
- return -ENOMEM;
- }
-
- pInfo->tx_buf = kmalloc(TX_BUF_SIZE, GFP_KERNEL);
- TRACE_M("r3964_open - tx_buf kmalloc %p", pInfo->tx_buf);
-
- if (!pInfo->tx_buf) {
- printk(KERN_ERR "r3964: failed to alloc transmit buffer\n");
- kfree(pInfo->rx_buf);
- TRACE_M("r3964_open - rx_buf kfree %p", pInfo->rx_buf);
- kfree(pInfo);
- TRACE_M("r3964_open - info kfree %p", pInfo);
- return -ENOMEM;
- }
-
- spin_lock_init(&pInfo->lock);
- mutex_init(&pInfo->read_lock);
- pInfo->tty = tty;
- pInfo->priority = R3964_MASTER;
- pInfo->rx_first = pInfo->rx_last = NULL;
- pInfo->tx_first = pInfo->tx_last = NULL;
- pInfo->rx_position = 0;
- pInfo->tx_position = 0;
- pInfo->last_rx = 0;
- pInfo->blocks_in_rx_queue = 0;
- pInfo->firstClient = NULL;
- pInfo->state = R3964_IDLE;
- pInfo->flags = R3964_DEBUG;
- pInfo->nRetry = 0;
-
- tty->disc_data = pInfo;
- tty->receive_room = 65536;
-
- timer_setup(&pInfo->tmr, on_timeout, 0);
-
- return 0;
-}
-
-static void r3964_close(struct tty_struct *tty)
-{
- struct r3964_info *pInfo = tty->disc_data;
- struct r3964_client_info *pClient, *pNext;
- struct r3964_message *pMsg;
- struct r3964_block_header *pHeader, *pNextHeader;
- unsigned long flags;
-
- TRACE_L("close");
-
- /*
- * Make sure that our task queue isn't activated. If it
- * is, take it out of the linked list.
- */
- del_timer_sync(&pInfo->tmr);
-
- /* Remove client-structs and message queues: */
- pClient = pInfo->firstClient;
- while (pClient) {
- pNext = pClient->next;
- while (pClient->msg_count) {
- pMsg = remove_msg(pInfo, pClient);
- if (pMsg) {
- kfree(pMsg);
- TRACE_M("r3964_close - msg kfree %p", pMsg);
- }
- }
- put_pid(pClient->pid);
- kfree(pClient);
- TRACE_M("r3964_close - client kfree %p", pClient);
- pClient = pNext;
- }
- /* Remove jobs from tx_queue: */
- spin_lock_irqsave(&pInfo->lock, flags);
- pHeader = pInfo->tx_first;
- pInfo->tx_first = pInfo->tx_last = NULL;
- spin_unlock_irqrestore(&pInfo->lock, flags);
-
- while (pHeader) {
- pNextHeader = pHeader->next;
- kfree(pHeader);
- pHeader = pNextHeader;
- }
-
- /* Free buffers: */
- kfree(pInfo->rx_buf);
- TRACE_M("r3964_close - rx_buf kfree %p", pInfo->rx_buf);
- kfree(pInfo->tx_buf);
- TRACE_M("r3964_close - tx_buf kfree %p", pInfo->tx_buf);
- kfree(pInfo);
- TRACE_M("r3964_close - info kfree %p", pInfo);
-}
-
-static ssize_t r3964_read(struct tty_struct *tty, struct file *file,
- unsigned char *kbuf, size_t nr,
- void **cookie, unsigned long offset)
-{
- struct r3964_info *pInfo = tty->disc_data;
- struct r3964_client_info *pClient;
- struct r3964_message *pMsg;
- struct r3964_client_message theMsg;
- int ret;
-
- TRACE_L("read()");
-
- /*
- * Internal serialization of reads.
- */
- if (file->f_flags & O_NONBLOCK) {
- if (!mutex_trylock(&pInfo->read_lock))
- return -EAGAIN;
- } else {
- if (mutex_lock_interruptible(&pInfo->read_lock))
- return -ERESTARTSYS;
- }
-
- pClient = findClient(pInfo, task_pid(current));
- if (pClient) {
- pMsg = remove_msg(pInfo, pClient);
- if (pMsg == NULL) {
- /* no messages available. */
- if (tty_io_nonblock(tty, file)) {
- ret = -EAGAIN;
- goto unlock;
- }
- /* block until there is a message: */
- wait_event_interruptible(tty->read_wait,
- (pMsg = remove_msg(pInfo, pClient)));
- }
-
- /* If we still haven't got a message, we must have been signalled */
-
- if (!pMsg) {
- ret = -EINTR;
- goto unlock;
- }
-
- /* deliver msg to client process: */
- theMsg.msg_id = pMsg->msg_id;
- theMsg.arg = pMsg->arg;
- theMsg.error_code = pMsg->error_code;
- ret = sizeof(struct r3964_client_message);
-
- kfree(pMsg);
- TRACE_M("r3964_read - msg kfree %p", pMsg);
-
- memcpy(kbuf, &theMsg, ret);
-
- TRACE_PS("read - return %d", ret);
- goto unlock;
- }
- ret = -EPERM;
-unlock:
- mutex_unlock(&pInfo->read_lock);
- return ret;
-}
-
-static ssize_t r3964_write(struct tty_struct *tty, struct file *file,
- const unsigned char *data, size_t count)
-{
- struct r3964_info *pInfo = tty->disc_data;
- struct r3964_block_header *pHeader;
- struct r3964_client_info *pClient;
- unsigned char *new_data;
-
- TRACE_L("write request, %d characters", count);
-/*
- * Verify the pointers
- */
-
- if (!pInfo)
- return -EIO;
-
-/*
- * Ensure that the caller does not wish to send too much.
- */
- if (count > R3964_MTU) {
- if (pInfo->flags & R3964_DEBUG) {
- TRACE_L(KERN_WARNING "r3964_write: truncating user "
- "packet from %u to mtu %d", count, R3964_MTU);
- }
- count = R3964_MTU;
- }
-/*
- * Allocate a buffer for the data and copy it from the buffer with header prepended
- */
- new_data = kmalloc(count + sizeof(struct r3964_block_header),
- GFP_KERNEL);
- TRACE_M("r3964_write - kmalloc %p", new_data);
- if (new_data == NULL) {
- if (pInfo->flags & R3964_DEBUG) {
- printk(KERN_ERR "r3964_write: no memory\n");
- }
- return -ENOSPC;
- }
-
- pHeader = (struct r3964_block_header *)new_data;
- pHeader->data = new_data + sizeof(struct r3964_block_header);
- pHeader->length = count;
- pHeader->locks = 0;
- pHeader->owner = NULL;
-
- pClient = findClient(pInfo, task_pid(current));
- if (pClient) {
- pHeader->owner = pClient;
- }
-
- memcpy(pHeader->data, data, count); /* We already verified this */
-
- if (pInfo->flags & R3964_DEBUG) {
- dump_block(pHeader->data, count);
- }
-
-/*
- * Add buffer to transmit-queue:
- */
- add_tx_queue(pInfo, pHeader);
- trigger_transmit(pInfo);
-
- return 0;
-}
-
-static int r3964_ioctl(struct tty_struct *tty, struct file *file,
- unsigned int cmd, unsigned long arg)
-{
- struct r3964_info *pInfo = tty->disc_data;
- if (pInfo == NULL)
- return -EINVAL;
- switch (cmd) {
- case R3964_ENABLE_SIGNALS:
- return enable_signals(pInfo, task_pid(current), arg);
- case R3964_SETPRIORITY:
- if (arg < R3964_MASTER || arg > R3964_SLAVE)
- return -EINVAL;
- pInfo->priority = arg & 0xff;
- return 0;
- case R3964_USE_BCC:
- if (arg)
- pInfo->flags |= R3964_BCC;
- else
- pInfo->flags &= ~R3964_BCC;
- return 0;
- case R3964_READ_TELEGRAM:
- return read_telegram(pInfo, task_pid(current),
- (unsigned char __user *)arg);
- default:
- return -ENOIOCTLCMD;
- }
-}
-
-#ifdef CONFIG_COMPAT
-static int r3964_compat_ioctl(struct tty_struct *tty, struct file *file,
- unsigned int cmd, unsigned long arg)
-{
- switch (cmd) {
- case R3964_ENABLE_SIGNALS:
- case R3964_SETPRIORITY:
- case R3964_USE_BCC:
- return r3964_ioctl(tty, file, cmd, arg);
- default:
- return -ENOIOCTLCMD;
- }
-}
-#endif
-
-static void r3964_set_termios(struct tty_struct *tty, struct ktermios *old)
-{
- TRACE_L("set_termios");
-}
-
-/* Called without the kernel lock held - fine */
-static __poll_t r3964_poll(struct tty_struct *tty, struct file *file,
- struct poll_table_struct *wait)
-{
- struct r3964_info *pInfo = tty->disc_data;
- struct r3964_client_info *pClient;
- struct r3964_message *pMsg = NULL;
- unsigned long flags;
- __poll_t result = EPOLLOUT;
-
- TRACE_L("POLL");
-
- pClient = findClient(pInfo, task_pid(current));
- if (pClient) {
- poll_wait(file, &tty->read_wait, wait);
- spin_lock_irqsave(&pInfo->lock, flags);
- pMsg = pClient->first_msg;
- spin_unlock_irqrestore(&pInfo->lock, flags);
- if (pMsg)
- result |= EPOLLIN | EPOLLRDNORM;
- } else {
- result = -EINVAL;
- }
- return result;
-}
-
-static void r3964_receive_buf(struct tty_struct *tty, const unsigned char *cp,
- char *fp, int count)
-{
- struct r3964_info *pInfo = tty->disc_data;
- const unsigned char *p;
- char *f, flags = TTY_NORMAL;
- int i;
-
- for (i = count, p = cp, f = fp; i; i--, p++) {
- if (f)
- flags = *f++;
- if (flags == TTY_NORMAL) {
- receive_char(pInfo, *p);
- } else {
- receive_error(pInfo, flags);
- }
-
- }
-}
-
-MODULE_LICENSE("GPL");
-MODULE_ALIAS_LDISC(N_R3964);
git.samba.org / sfrench / cifs-2.6.git / commitdiff