[net-next-2.6.git] / drivers / isdn / hysdn / hysdn_proclog.c

/* $Id: hysdn_proclog.c,v 1.9.6.3 2001/09/23 22:24:54 kai Exp $
 *
 * Linux driver for HYSDN cards, /proc/net filesystem log functions.
 *
 * Author    Werner Cornelius (werner@titro.de) for Hypercope GmbH
 * Copyright 1999 by Werner Cornelius (werner@titro.de)
 *
 * This software may be used and distributed according to the terms
 * of the GNU General Public License, incorporated herein by reference.
 *
 */

#include <linux/module.h>
#include <linux/poll.h>
#include <linux/proc_fs.h>
#include <linux/sched.h>
#include <linux/smp_lock.h>

#include "hysdn_defs.h"

/* the proc subdir for the interface is defined in the procconf module */
extern struct proc_dir_entry *hysdn_proc_entry;

static void put_log_buffer(hysdn_card * card, char *cp);

/*************************************************/
/* structure keeping ascii log for device output */
/*************************************************/
struct log_data {
	struct log_data *next;
	unsigned long usage_cnt;/* number of files still to work */
	void *proc_ctrl;	/* pointer to own control procdata structure */
	char log_start[2];	/* log string start (final len aligned by size) */
};

/**********************************************/
/* structure holding proc entrys for one card */
/**********************************************/
struct procdata {
	struct proc_dir_entry *log;	/* log entry */
	char log_name[15];	/* log filename */
	struct log_data *log_head, *log_tail;	/* head and tail for queue */
	int if_used;		/* open count for interface */
	int volatile del_lock;	/* lock for delete operations */
	unsigned char logtmp[LOG_MAX_LINELEN];
	wait_queue_head_t rd_queue;
};


/**********************************************/
/* log function for cards error log interface */
/**********************************************/
void
hysdn_card_errlog(hysdn_card * card, tErrLogEntry * logp, int maxsize)
{
	char buf[ERRLOG_TEXT_SIZE + 40];

	sprintf(buf, "LOG 0x%08lX 0x%08lX : %s\n", logp->ulErrType, logp->ulErrSubtype, logp->ucText);
	put_log_buffer(card, buf);	/* output the string */
}				/* hysdn_card_errlog */

/***************************************************/
/* Log function using format specifiers for output */
/***************************************************/
void
hysdn_addlog(hysdn_card * card, char *fmt,...)
{
	struct procdata *pd = card->proclog;
	char *cp;
	va_list args;

	if (!pd)
		return;		/* log structure non existent */

	cp = pd->logtmp;
	cp += sprintf(cp, "HYSDN: card %d ", card->myid);

	va_start(args, fmt);
	cp += vsprintf(cp, fmt, args);
	va_end(args);
	*cp++ = '\n';
	*cp = 0;

	if (card->debug_flags & DEB_OUT_SYSLOG)
		printk(KERN_INFO "%s", pd->logtmp);
	else
		put_log_buffer(card, pd->logtmp);

}				/* hysdn_addlog */

/********************************************/
/* put an log buffer into the log queue.    */
/* This buffer will be kept until all files */
/* opened for read got the contents.        */
/* Flushes buffers not longer in use.       */
/********************************************/
static void
put_log_buffer(hysdn_card * card, char *cp)
{
	struct log_data *ib;
	struct procdata *pd = card->proclog;
	int i;
	unsigned long flags;

	if (!pd)
		return;
	if (!cp)
		return;
	if (!*cp)
		return;
	if (pd->if_used <= 0)
		return;		/* no open file for read */

	if (!(ib = kmalloc(sizeof(struct log_data) + strlen(cp), GFP_ATOMIC)))
		 return;	/* no memory */
	strcpy(ib->log_start, cp);	/* set output string */
	ib->next = NULL;
	ib->proc_ctrl = pd;	/* point to own control structure */
	spin_lock_irqsave(&card->hysdn_lock, flags);
	ib->usage_cnt = pd->if_used;
	if (!pd->log_head)
		pd->log_head = ib;	/* new head */
	else
		pd->log_tail->next = ib;	/* follows existing messages */
	pd->log_tail = ib;	/* new tail */
	i = pd->del_lock++;	/* get lock state */
	spin_unlock_irqrestore(&card->hysdn_lock, flags);

	/* delete old entrys */
	if (!i)
		while (pd->log_head->next) {
			if ((pd->log_head->usage_cnt <= 0) &&
			    (pd->log_head->next->usage_cnt <= 0)) {
				ib = pd->log_head;
				pd->log_head = pd->log_head->next;
				kfree(ib);
			} else
				break;
		}		/* pd->log_head->next */
	pd->del_lock--;		/* release lock level */
	wake_up_interruptible(&(pd->rd_queue));		/* announce new entry */
}				/* put_log_buffer */


/******************************/
/* file operations and tables */
/******************************/

/****************************************/
/* write log file -> set log level bits */
/****************************************/
static ssize_t
hysdn_log_write(struct file *file, const char __user *buf, size_t count, loff_t * off)
{
	unsigned long u = 0;
	int found = 0;
	unsigned char *cp, valbuf[128];
	long base = 10;
	hysdn_card *card = (hysdn_card *) file->private_data;

	if (count > (sizeof(valbuf) - 1))
		count = sizeof(valbuf) - 1;	/* limit length */
	if (copy_from_user(valbuf, buf, count))
		return (-EFAULT);	/* copy failed */

	valbuf[count] = 0;	/* terminating 0 */
	cp = valbuf;
	if ((count > 2) && (valbuf[0] == '0') && (valbuf[1] == 'x')) {
		cp += 2;	/* pointer after hex modifier */
		base = 16;
	}
	/* scan the input for debug flags */
	while (*cp) {
		if ((*cp >= '0') && (*cp <= '9')) {
			found = 1;
			u *= base;	/* adjust to next digit */
			u += *cp++ - '0';
			continue;
		}
		if (base != 16)
			break;	/* end of number */

		if ((*cp >= 'a') && (*cp <= 'f')) {
			found = 1;
			u *= base;	/* adjust to next digit */
			u += *cp++ - 'a' + 10;
			continue;
		}
		break;		/* terminated */
	}

	if (found) {
		card->debug_flags = u;	/* remember debug flags */
		hysdn_addlog(card, "debug set to 0x%lx", card->debug_flags);
	}
	return (count);
}				/* hysdn_log_write */

/******************/
/* read log file */
/******************/
static ssize_t
hysdn_log_read(struct file *file, char __user *buf, size_t count, loff_t * off)
{
	struct log_data *inf;
	int len;
	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
	struct procdata *pd = NULL;
	hysdn_card *card;

	if (!*((struct log_data **) file->private_data)) {
		if (file->f_flags & O_NONBLOCK)
			return (-EAGAIN);

		/* sorry, but we need to search the card */
		card = card_root;
		while (card) {
			pd = card->proclog;
			if (pd->log == pde)
				break;
			card = card->next;	/* search next entry */
		}
		if (card)
			interruptible_sleep_on(&(pd->rd_queue));
		else
			return (-EAGAIN);

	}
	if (!(inf = *((struct log_data **) file->private_data)))
		return (0);

	inf->usage_cnt--;	/* new usage count */
	file->private_data = &inf->next;	/* next structure */
	if ((len = strlen(inf->log_start)) <= count) {
		if (copy_to_user(buf, inf->log_start, len))
			return -EFAULT;
		*off += len;
		return (len);
	}
	return (0);
}				/* hysdn_log_read */

/******************/
/* open log file */
/******************/
static int
hysdn_log_open(struct inode *ino, struct file *filep)
{
	hysdn_card *card;
	struct procdata *pd = NULL;
	unsigned long flags;

	lock_kernel();
	card = card_root;
	while (card) {
		pd = card->proclog;
		if (pd->log == PDE(ino))
			break;
		card = card->next;	/* search next entry */
	}
	if (!card) {
		unlock_kernel();
		return (-ENODEV);	/* device is unknown/invalid */
	}
	filep->private_data = card;	/* remember our own card */

	if ((filep->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_WRITE) {
		/* write only access -> write log level only */
	} else if ((filep->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) {

		/* read access -> log/debug read */
		spin_lock_irqsave(&card->hysdn_lock, flags);
		pd->if_used++;
		if (pd->log_head)
			filep->private_data = &pd->log_tail->next;
		else
			filep->private_data = &pd->log_head;
		spin_unlock_irqrestore(&card->hysdn_lock, flags);
	} else {		/* simultaneous read/write access forbidden ! */
		unlock_kernel();
		return (-EPERM);	/* no permission this time */
	}
	unlock_kernel();
	return nonseekable_open(ino, filep);
}				/* hysdn_log_open */

/*******************************************************************************/
/* close a cardlog file. If the file has been opened for exclusive write it is */
/* assumed as pof data input and the pof loader is noticed about.              */
/* Otherwise file is handled as log output. In this case the interface usage   */
/* count is decremented and all buffers are noticed of closing. If this file   */
/* was the last one to be closed, all buffers are freed.                       */
/*******************************************************************************/
static int
hysdn_log_close(struct inode *ino, struct file *filep)
{
	struct log_data *inf;
	struct procdata *pd;
	hysdn_card *card;
	int retval = 0;

	lock_kernel();
	if ((filep->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_WRITE) {
		/* write only access -> write debug level written */
		retval = 0;	/* success */
	} else {
		/* read access -> log/debug read, mark one further file as closed */

		pd = NULL;
		inf = *((struct log_data **) filep->private_data);	/* get first log entry */
		if (inf)
			pd = (struct procdata *) inf->proc_ctrl;	/* still entries there */
		else {
			/* no info available -> search card */
			card = card_root;
			while (card) {
				pd = card->proclog;
				if (pd->log == PDE(ino))
					break;
				card = card->next;	/* search next entry */
			}
			if (card)
				pd = card->proclog;	/* pointer to procfs log */
		}
		if (pd)
			pd->if_used--;	/* decrement interface usage count by one */

		while (inf) {
			inf->usage_cnt--;	/* decrement usage count for buffers */
			inf = inf->next;
		}

		if (pd)
			if (pd->if_used <= 0)	/* delete buffers if last file closed */
				while (pd->log_head) {
					inf = pd->log_head;
					pd->log_head = pd->log_head->next;
					kfree(inf);
				}
	}			/* read access */
	unlock_kernel();

	return (retval);
}				/* hysdn_log_close */

/*************************************************/
/* select/poll routine to be able using select() */
/*************************************************/
static unsigned int
hysdn_log_poll(struct file *file, poll_table * wait)
{
	unsigned int mask = 0;
	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
	hysdn_card *card;
	struct procdata *pd = NULL;

	if ((file->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_WRITE)
		return (mask);	/* no polling for write supported */

	/* we need to search the card */
	card = card_root;
	while (card) {
		pd = card->proclog;
		if (pd->log == pde)
			break;
		card = card->next;	/* search next entry */
	}
	if (!card)
		return (mask);	/* card not found */

	poll_wait(file, &(pd->rd_queue), wait);

	if (*((struct log_data **) file->private_data))
		mask |= POLLIN | POLLRDNORM;

	return mask;
}				/* hysdn_log_poll */

/**************************************************/
/* table for log filesystem functions defined above. */
/**************************************************/
static const struct file_operations log_fops =
{
	.owner		= THIS_MODULE,
	.llseek         = no_llseek,
	.read           = hysdn_log_read,
	.write          = hysdn_log_write,
	.poll           = hysdn_log_poll,
	.open           = hysdn_log_open,
	.release        = hysdn_log_close,                                        
};


/***********************************************************************************/
/* hysdn_proclog_init is called when the module is loaded after creating the cards */
/* conf files.                                                                     */
/***********************************************************************************/
int
hysdn_proclog_init(hysdn_card * card)
{
	struct procdata *pd;

	/* create a cardlog proc entry */

	if ((pd = kzalloc(sizeof(struct procdata), GFP_KERNEL)) != NULL) {
		sprintf(pd->log_name, "%s%d", PROC_LOG_BASENAME, card->myid);
		pd->log = proc_create(pd->log_name,
				S_IFREG | S_IRUGO | S_IWUSR, hysdn_proc_entry,
				&log_fops);

		init_waitqueue_head(&(pd->rd_queue));

		card->proclog = (void *) pd;	/* remember procfs structure */
	}
	return (0);
}				/* hysdn_proclog_init */

/************************************************************************************/
/* hysdn_proclog_release is called when the module is unloaded and before the cards */
/* conf file is released                                                            */
/* The module counter is assumed to be 0 !                                          */
/************************************************************************************/
void
hysdn_proclog_release(hysdn_card * card)
{
	struct procdata *pd;

	if ((pd = (struct procdata *) card->proclog) != NULL) {
		if (pd->log)
			remove_proc_entry(pd->log_name, hysdn_proc_entry);
		kfree(pd);	/* release memory */
		card->proclog = NULL;
	}
}				/* hysdn_proclog_release */
Commit	Line	Data
1da177e4 LT	1	/* $Id: hysdn_proclog.c,v 1.9.6.3 2001/09/23 22:24:54 kai Exp $
	2	*
	3	* Linux driver for HYSDN cards, /proc/net filesystem log functions.
	4	*
	5	* Author Werner Cornelius (werner@titro.de) for Hypercope GmbH
	6	* Copyright 1999 by Werner Cornelius (werner@titro.de)
	7	*
	8	* This software may be used and distributed according to the terms
	9	* of the GNU General Public License, incorporated herein by reference.
	10	*
	11	*/
	12
	13	#include <linux/module.h>
1da177e4 LT	14	#include <linux/poll.h>
1da177e4 LT	15	#include <linux/proc_fs.h>
d43c36dc	16	#include <linux/sched.h>
1da177e4 LT	17	#include <linux/smp_lock.h>
	18
	19	#include "hysdn_defs.h"
	20
	21	/* the proc subdir for the interface is defined in the procconf module */
	22	extern struct proc_dir_entry *hysdn_proc_entry;
	23
aade0e82 AB	24	static void put_log_buffer(hysdn_card * card, char *cp);
aade0e82 AB	25
1da177e4 LT	26	/*************************************************/
	27	/* structure keeping ascii log for device output */
	28	/*************************************************/
	29	struct log_data {
	30	struct log_data *next;
c721bcce	31	unsigned long usage_cnt;/* number of files still to work */
1da177e4 LT	32	void proc_ctrl; / pointer to own control procdata structure */
	33	char log_start[2]; /* log string start (final len aligned by size) */
	34	};
	35
	36	/**********************************************/
	37	/* structure holding proc entrys for one card */
	38	/**********************************************/
	39	struct procdata {
	40	struct proc_dir_entry log; / log entry */
	41	char log_name[15]; /* log filename */
	42	struct log_data log_head, log_tail; /* head and tail for queue */
	43	int if_used; /* open count for interface */
	44	int volatile del_lock; /* lock for delete operations */
c721bcce	45	unsigned char logtmp[LOG_MAX_LINELEN];
1da177e4 LT	46	wait_queue_head_t rd_queue;
	47	};
	48
	49
	50	/**********************************************/
	51	/* log function for cards error log interface */
	52	/**********************************************/
	53	void
	54	hysdn_card_errlog(hysdn_card * card, tErrLogEntry * logp, int maxsize)
	55	{
	56	char buf[ERRLOG_TEXT_SIZE + 40];
	57
	58	sprintf(buf, "LOG 0x%08lX 0x%08lX : %s\n", logp->ulErrType, logp->ulErrSubtype, logp->ucText);
	59	put_log_buffer(card, buf); /* output the string */
	60	} /* hysdn_card_errlog */
	61
	62	/***************************************************/
	63	/* Log function using format specifiers for output */
	64	/***************************************************/
	65	void
	66	hysdn_addlog(hysdn_card * card, char *fmt,...)
	67	{
	68	struct procdata *pd = card->proclog;
	69	char *cp;
	70	va_list args;
	71
	72	if (!pd)
	73	return; /* log structure non existent */
	74
	75	cp = pd->logtmp;
	76	cp += sprintf(cp, "HYSDN: card %d ", card->myid);
	77
	78	va_start(args, fmt);
	79	cp += vsprintf(cp, fmt, args);
	80	va_end(args);
	81	*cp++ = '\n';
	82	*cp = 0;
	83
	84	if (card->debug_flags & DEB_OUT_SYSLOG)
	85	printk(KERN_INFO "%s", pd->logtmp);
	86	else
	87	put_log_buffer(card, pd->logtmp);
	88
	89	} /* hysdn_addlog */
	90
	91	/********************************************/
	92	/* put an log buffer into the log queue. */
	93	/* This buffer will be kept until all files */
	94	/* opened for read got the contents. */
	95	/* Flushes buffers not longer in use. */
	96	/********************************************/
aade0e82	97	static void
1da177e4 LT	98	put_log_buffer(hysdn_card * card, char *cp)
	99	{
	100	struct log_data *ib;
	101	struct procdata *pd = card->proclog;
	102	int i;
	103	unsigned long flags;
	104
	105	if (!pd)
	106	return;
	107	if (!cp)
	108	return;
	109	if (!*cp)
	110	return;
	111	if (pd->if_used <= 0)
	112	return; /* no open file for read */
	113
5cbded58	114	if (!(ib = kmalloc(sizeof(struct log_data) + strlen(cp), GFP_ATOMIC)))
1da177e4 LT	115	return; /* no memory */
	116	strcpy(ib->log_start, cp); /* set output string */
	117	ib->next = NULL;
	118	ib->proc_ctrl = pd; /* point to own control structure */
0d9ba869	119	spin_lock_irqsave(&card->hysdn_lock, flags);
1da177e4 LT	120	ib->usage_cnt = pd->if_used;
	121	if (!pd->log_head)
	122	pd->log_head = ib; /* new head */
	123	else
	124	pd->log_tail->next = ib; /* follows existing messages */
	125	pd->log_tail = ib; /* new tail */
	126	i = pd->del_lock++; /* get lock state */
0d9ba869	127	spin_unlock_irqrestore(&card->hysdn_lock, flags);
1da177e4 LT	128
	129	/* delete old entrys */
	130	if (!i)
	131	while (pd->log_head->next) {
	132	if ((pd->log_head->usage_cnt <= 0) &&
	133	(pd->log_head->next->usage_cnt <= 0)) {
	134	ib = pd->log_head;
	135	pd->log_head = pd->log_head->next;
	136	kfree(ib);
	137	} else
	138	break;
	139	} /* pd->log_head->next */
	140	pd->del_lock--; /* release lock level */
	141	wake_up_interruptible(&(pd->rd_queue)); /* announce new entry */
	142	} /* put_log_buffer */
	143
	144
	145	/******************************/
	146	/* file operations and tables */
	147	/******************************/
	148
	149	/****************************************/
	150	/* write log file -> set log level bits */
	151	/****************************************/
	152	static ssize_t
	153	hysdn_log_write(struct file file, const char __user buf, size_t count, loff_t * off)
	154	{
c721bcce	155	unsigned long u = 0;
1da177e4	156	int found = 0;
c721bcce	157	unsigned char *cp, valbuf[128];
1da177e4 LT	158	long base = 10;
	159	hysdn_card card = (hysdn_card ) file->private_data;
	160
	161	if (count > (sizeof(valbuf) - 1))
	162	count = sizeof(valbuf) - 1; /* limit length */
	163	if (copy_from_user(valbuf, buf, count))
	164	return (-EFAULT); /* copy failed */
	165
	166	valbuf[count] = 0; /* terminating 0 */
	167	cp = valbuf;
	168	if ((count > 2) && (valbuf[0] == '0') && (valbuf[1] == 'x')) {
	169	cp += 2; /* pointer after hex modifier */
	170	base = 16;
	171	}
	172	/* scan the input for debug flags */
	173	while (*cp) {
	174	if ((cp >= '0') && (cp <= '9')) {
	175	found = 1;
	176	u = base; / adjust to next digit */
	177	u += *cp++ - '0';
	178	continue;
	179	}
	180	if (base != 16)
	181	break; /* end of number */
	182
	183	if ((cp >= 'a') && (cp <= 'f')) {
	184	found = 1;
	185	u = base; / adjust to next digit */
	186	u += *cp++ - 'a' + 10;
	187	continue;
	188	}
	189	break; /* terminated */
	190	}
	191
	192	if (found) {
	193	card->debug_flags = u; /* remember debug flags */
	194	hysdn_addlog(card, "debug set to 0x%lx", card->debug_flags);
	195	}
	196	return (count);
	197	} /* hysdn_log_write */
	198
	199	/******************/
	200	/* read log file */
	201	/******************/
	202	static ssize_t
	203	hysdn_log_read(struct file file, char __user buf, size_t count, loff_t * off)
	204	{
	205	struct log_data *inf;
	206	int len;
4482dfad	207	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
1da177e4 LT	208	struct procdata *pd = NULL;
	209	hysdn_card *card;
	210
	211	if (!((struct log_data *) file->private_data)) {
	212	if (file->f_flags & O_NONBLOCK)
	213	return (-EAGAIN);
	214
	215	/* sorry, but we need to search the card */
	216	card = card_root;
	217	while (card) {
	218	pd = card->proclog;
	219	if (pd->log == pde)
	220	break;
	221	card = card->next; /* search next entry */
	222	}
	223	if (card)
	224	interruptible_sleep_on(&(pd->rd_queue));
	225	else
	226	return (-EAGAIN);
	227
	228	}
	229	if (!(inf = ((struct log_data *) file->private_data)))
	230	return (0);
	231
	232	inf->usage_cnt--; /* new usage count */
	233	file->private_data = &inf->next; /* next structure */
	234	if ((len = strlen(inf->log_start)) <= count) {
	235	if (copy_to_user(buf, inf->log_start, len))
	236	return -EFAULT;
	237	*off += len;
	238	return (len);
	239	}
	240	return (0);
	241	} /* hysdn_log_read */
	242
	243	/******************/
	244	/* open log file */
	245	/******************/
	246	static int
	247	hysdn_log_open(struct inode ino, struct file filep)
	248	{
	249	hysdn_card *card;
	250	struct procdata *pd = NULL;
c721bcce	251	unsigned long flags;
1da177e4 LT	252
	253	lock_kernel();
	254	card = card_root;
	255	while (card) {
	256	pd = card->proclog;
	257	if (pd->log == PDE(ino))
	258	break;
	259	card = card->next; /* search next entry */
	260	}
	261	if (!card) {
	262	unlock_kernel();
	263	return (-ENODEV); /* device is unknown/invalid */
	264	}
	265	filep->private_data = card; /* remember our own card */
	266
	267	if ((filep->f_mode & (FMODE_READ \| FMODE_WRITE)) == FMODE_WRITE) {
	268	/* write only access -> write log level only */
	269	} else if ((filep->f_mode & (FMODE_READ \| FMODE_WRITE)) == FMODE_READ) {
	270
	271	/* read access -> log/debug read */
0d9ba869	272	spin_lock_irqsave(&card->hysdn_lock, flags);
1da177e4 LT	273	pd->if_used++;
	274	if (pd->log_head)
	275	filep->private_data = &pd->log_tail->next;
	276	else
	277	filep->private_data = &pd->log_head;
0d9ba869	278	spin_unlock_irqrestore(&card->hysdn_lock, flags);
1da177e4 LT	279	} else { /* simultaneous read/write access forbidden ! */
	280	unlock_kernel();
	281	return (-EPERM); /* no permission this time */
	282	}
	283	unlock_kernel();
	284	return nonseekable_open(ino, filep);
	285	} /* hysdn_log_open */
	286
	287	/*******************************************************************************/
	288	/* close a cardlog file. If the file has been opened for exclusive write it is */
	289	/* assumed as pof data input and the pof loader is noticed about. */
	290	/* Otherwise file is handled as log output. In this case the interface usage */
	291	/* count is decremented and all buffers are noticed of closing. If this file */
	292	/* was the last one to be closed, all buffers are freed. */
	293	/*******************************************************************************/
	294	static int
	295	hysdn_log_close(struct inode ino, struct file filep)
	296	{
	297	struct log_data *inf;
	298	struct procdata *pd;
	299	hysdn_card *card;
	300	int retval = 0;
1da177e4 LT	301
	302	lock_kernel();
	303	if ((filep->f_mode & (FMODE_READ \| FMODE_WRITE)) == FMODE_WRITE) {
	304	/* write only access -> write debug level written */
	305	retval = 0; /* success */
	306	} else {
	307	/* read access -> log/debug read, mark one further file as closed */
	308
	309	pd = NULL;
1da177e4 LT	310	inf = ((struct log_data ) filep->private_data); / get first log entry */
	311	if (inf)
	312	pd = (struct procdata ) inf->proc_ctrl; / still entries there */
	313	else {
	314	/* no info available -> search card */
	315	card = card_root;
	316	while (card) {
	317	pd = card->proclog;
	318	if (pd->log == PDE(ino))
	319	break;
	320	card = card->next; /* search next entry */
	321	}
	322	if (card)
	323	pd = card->proclog; /* pointer to procfs log */
	324	}
	325	if (pd)
	326	pd->if_used--; /* decrement interface usage count by one */
	327
	328	while (inf) {
	329	inf->usage_cnt--; /* decrement usage count for buffers */
	330	inf = inf->next;
	331	}
1da177e4 LT	332
	333	if (pd)
	334	if (pd->if_used <= 0) /* delete buffers if last file closed */
	335	while (pd->log_head) {
	336	inf = pd->log_head;
	337	pd->log_head = pd->log_head->next;
	338	kfree(inf);
	339	}
	340	} /* read access */
	341	unlock_kernel();
	342
	343	return (retval);
	344	} /* hysdn_log_close */
	345
	346	/*************************************************/
	347	/* select/poll routine to be able using select() */
	348	/*************************************************/
	349	static unsigned int
	350	hysdn_log_poll(struct file file, poll_table wait)
	351	{
	352	unsigned int mask = 0;
4482dfad	353	struct proc_dir_entry *pde = PDE(file->f_path.dentry->d_inode);
1da177e4 LT	354	hysdn_card *card;
	355	struct procdata *pd = NULL;
	356
	357	if ((file->f_mode & (FMODE_READ \| FMODE_WRITE)) == FMODE_WRITE)
	358	return (mask); /* no polling for write supported */
	359
	360	/* we need to search the card */
	361	card = card_root;
	362	while (card) {
	363	pd = card->proclog;
	364	if (pd->log == pde)
	365	break;
	366	card = card->next; /* search next entry */
	367	}
	368	if (!card)
	369	return (mask); /* card not found */
	370
	371	poll_wait(file, &(pd->rd_queue), wait);
	372
	373	if (((struct log_data *) file->private_data))
	374	mask \|= POLLIN \| POLLRDNORM;
	375
	376	return mask;
	377	} /* hysdn_log_poll */
	378
	379	/**************************************************/
	380	/* table for log filesystem functions defined above. */
	381	/**************************************************/
2b8693c0	382	static const struct file_operations log_fops =
1da177e4	383	{
ac41cfd1	384	.owner = THIS_MODULE,
1da177e4 LT	385	.llseek = no_llseek,
	386	.read = hysdn_log_read,
	387	.write = hysdn_log_write,
	388	.poll = hysdn_log_poll,
	389	.open = hysdn_log_open,
	390	.release = hysdn_log_close,
	391	};
	392
	393
	394	/***********************************************************************************/
	395	/* hysdn_proclog_init is called when the module is loaded after creating the cards */
	396	/* conf files. */
	397	/***********************************************************************************/
	398	int
	399	hysdn_proclog_init(hysdn_card * card)
	400	{
	401	struct procdata *pd;
	402
	403	/* create a cardlog proc entry */
	404
41f96935	405	if ((pd = kzalloc(sizeof(struct procdata), GFP_KERNEL)) != NULL) {
1da177e4	406	sprintf(pd->log_name, "%s%d", PROC_LOG_BASENAME, card->myid);
ac41cfd1 DL	407	pd->log = proc_create(pd->log_name,
	408	S_IFREG \| S_IRUGO \| S_IWUSR, hysdn_proc_entry,
	409	&log_fops);
1da177e4 LT	410
	411	init_waitqueue_head(&(pd->rd_queue));
	412
	413	card->proclog = (void ) pd; / remember procfs structure */
	414	}
	415	return (0);
	416	} /* hysdn_proclog_init */
	417
	418	/************************************************************************************/
	419	/* hysdn_proclog_release is called when the module is unloaded and before the cards */
	420	/* conf file is released */
	421	/* The module counter is assumed to be 0 ! */
	422	/************************************************************************************/
	423	void
	424	hysdn_proclog_release(hysdn_card * card)
	425	{
	426	struct procdata *pd;
	427
	428	if ((pd = (struct procdata *) card->proclog) != NULL) {
	429	if (pd->log)
	430	remove_proc_entry(pd->log_name, hysdn_proc_entry);
	431	kfree(pd); /* release memory */
	432	card->proclog = NULL;
	433	}
	434	} /* hysdn_proclog_release */