linux-hardened/include/linux/n_r3964.h
Eric W. Biederman 3cec556a84 [PATCH] n_r3964: Use struct pid to track user space clients
Currently this driver tracks user space clients it should send signals to.  In
the presenct of file descriptor passing this is appears susceptible to
confusion from pid wrap around issues.

Replacing this with a struct pid prevents us from getting confused, and
prepares for a pid namespace implementation.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-13 09:05:53 -08:00

232 lines
5.2 KiB
C

/* r3964 linediscipline for linux
*
* -----------------------------------------------------------
* Copyright by
* Philips Automation Projects
* Kassel (Germany)
* http://www.pap-philips.de
* -----------------------------------------------------------
* This software may be used and distributed according to the terms of
* the GNU General Public License, incorporated herein by reference.
*
* Author:
* L. Haag
*
* $Log: r3964.h,v $
* Revision 1.4 2005/12/21 19:54:24 Kurt Huwig <kurt huwig de>
* Fixed HZ usage on 2.6 kernels
* Removed unnecessary include
*
* Revision 1.3 2001/03/18 13:02:24 dwmw2
* Fix timer usage, use spinlocks properly.
*
* Revision 1.2 2001/03/18 12:53:15 dwmw2
* Merge changes in 2.4.2
*
* Revision 1.1.1.1 1998/10/13 16:43:14 dwmw2
* This'll screw the version control
*
* Revision 1.6 1998/09/30 00:40:38 dwmw2
* Updated to use kernel's N_R3964 if available
*
* Revision 1.4 1998/04/02 20:29:44 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 13:03:17 root
* ioctl read_telegram
*
* Revision 1.1 1998/02/06 19:19:43 root
* Initial revision
*
*
*/
#ifndef __LINUX_N_R3964_H__
#define __LINUX_N_R3964_H__
/* line disciplines for r3964 protocol */
#ifdef __KERNEL__
#include <linux/param.h>
/*
* Common ascii handshake characters:
*/
#define STX 0x02
#define ETX 0x03
#define DLE 0x10
#define NAK 0x15
/*
* Timeouts (from milliseconds to jiffies)
*/
#define R3964_TO_QVZ ((550)*HZ/1000)
#define R3964_TO_ZVZ ((220)*HZ/1000)
#define R3964_TO_NO_BUF ((400)*HZ/1000)
#define R3964_NO_TX_ROOM ((100)*HZ/1000)
#define R3964_TO_RX_PANIC ((4000)*HZ/1000)
#define R3964_MAX_RETRIES 5
#endif
/*
* Ioctl-commands
*/
#define R3964_ENABLE_SIGNALS 0x5301
#define R3964_SETPRIORITY 0x5302
#define R3964_USE_BCC 0x5303
#define R3964_READ_TELEGRAM 0x5304
/* Options for R3964_SETPRIORITY */
#define R3964_MASTER 0
#define R3964_SLAVE 1
/* Options for R3964_ENABLE_SIGNALS */
#define R3964_SIG_ACK 0x0001
#define R3964_SIG_DATA 0x0002
#define R3964_SIG_ALL 0x000f
#define R3964_SIG_NONE 0x0000
#define R3964_USE_SIGIO 0x1000
/*
* r3964 operation states:
*/
#ifdef __KERNEL__
enum { R3964_IDLE,
R3964_TX_REQUEST, R3964_TRANSMITTING,
R3964_WAIT_ZVZ_BEFORE_TX_RETRY, R3964_WAIT_FOR_TX_ACK,
R3964_WAIT_FOR_RX_BUF,
R3964_RECEIVING, R3964_WAIT_FOR_BCC, R3964_WAIT_FOR_RX_REPEAT
};
/*
* All open file-handles are 'clients' and are stored in a linked list:
*/
struct r3964_message;
struct r3964_client_info {
spinlock_t lock;
struct pid *pid;
unsigned int sig_flags;
struct r3964_client_info *next;
struct r3964_message *first_msg;
struct r3964_message *last_msg;
struct r3964_block_header *next_block_to_read;
int msg_count;
};
#endif
/* types for msg_id: */
enum {R3964_MSG_ACK=1, R3964_MSG_DATA };
#define R3964_MAX_MSG_COUNT 32
/* error codes for client messages */
#define R3964_OK 0 /* no error. */
#define R3964_TX_FAIL -1 /* transmission error, block NOT sent */
#define R3964_OVERFLOW -2 /* msg queue overflow */
/* the client gets this struct when calling read(fd,...): */
struct r3964_client_message {
int msg_id;
int arg;
int error_code;
};
#define R3964_MTU 256
#ifdef __KERNEL__
struct r3964_block_header;
/* internal version of client_message: */
struct r3964_message {
int msg_id;
int arg;
int error_code;
struct r3964_block_header *block;
struct r3964_message *next;
};
/*
* Header of received block in rx_buf/tx_buf:
*/
struct r3964_block_header
{
unsigned int length; /* length in chars without header */
unsigned char *data; /* usually data is located
immediately behind this struct */
unsigned int locks; /* only used in rx_buffer */
struct r3964_block_header *next;
struct r3964_client_info *owner; /* =NULL in rx_buffer */
};
/*
* If rx_buf hasn't enough space to store R3964_MTU chars,
* we will reject all incoming STX-requests by sending NAK.
*/
#define RX_BUF_SIZE 4000
#define TX_BUF_SIZE 4000
#define R3964_MAX_BLOCKS_IN_RX_QUEUE 100
#define R3964_PARITY 0x0001
#define R3964_FRAME 0x0002
#define R3964_OVERRUN 0x0004
#define R3964_UNKNOWN 0x0008
#define R3964_BREAK 0x0010
#define R3964_CHECKSUM 0x0020
#define R3964_ERROR 0x003f
#define R3964_BCC 0x4000
#define R3964_DEBUG 0x8000
struct r3964_info {
spinlock_t lock;
struct tty_struct *tty;
unsigned char priority;
unsigned char *rx_buf; /* ring buffer */
unsigned char *tx_buf;
wait_queue_head_t read_wait;
//struct wait_queue *read_wait;
struct r3964_block_header *rx_first;
struct r3964_block_header *rx_last;
struct r3964_block_header *tx_first;
struct r3964_block_header *tx_last;
unsigned int tx_position;
unsigned int rx_position;
unsigned char last_rx;
unsigned char bcc;
unsigned int blocks_in_rx_queue;
struct r3964_client_info *firstClient;
unsigned int state;
unsigned int flags;
struct timer_list tmr;
int nRetry;
};
#endif
#endif