File /code/strss7/drivers/dl/dl.c

#ident "@(#) $RCSfile: dl.c,v $ $Name:  $($Revision: 0.8.2.9 $) $Date: 2003/06/25 09:38:21 $"

static char const ident[] = "$RCSfile: dl.c,v $ $Name:  $($Revision: 0.8.2.9 $) $Date: 2003/06/25 09:38:21 $";

#include <linux/config.h>
#include <linux/version.h>
#ifdef MODVERSIONS
#include <linux/modversions.h>
#endif
#include <linux/module.h>

#include <sys/stream.h>
#include <sys/stropts.h>
#include <sys/cmn_err.h>
#include <sys/dki.h>
#include <sys/ddi.h>
#include <sys/osif.h>

#include "../debug.h"

#define DL_DESCRIP	"Data Link (DL) STREAMS MULTIPLEXING DRIVER ($Revision: 0.8.2.9 $)"
#define DL_COPYRIGHT	"Copyright (c) 1997-2003  OpenSS7 Corporation.  All Rights Reserved."
#define DL_DEVICE	"OpenSS7 CDI Devices."
#define DL_CONTACT	"Brian Bidulock <bidulock@openss7.org>"
#define DL_LICENSE	"GPL"
#define DL_BANNER	DL_DESCRIP	"\n" \
			DL_COPYRIGHT	"\n" \
			DL_DEVICE	"\n" \
			DL_CONTACT

MODULE_AUTHOR(DL_CONTACT);
MODULE_DESCRIPTION(DL_DESCRIP);
MODULE_SUPPORTED_DEVICE(DL_DEVICE);
#ifdef MODULE_LICENSE
MODULE_LICENSE(DL_LICENSE);
#endif

/*
 *  =========================================================================
 *
 *  STREAMS Definitions
 *
 *  =========================================================================
 */

#define DL_DRV_ID	'd'
#define DL_DRV_NAME	"dl"

STATIC struct module_info dl_xinfo = {
	mi_idnum:DL_DRV_ID,			/* Module ID number */
	mi_idname:DL_DRV_NAME,			/* Module ID name */
	mi_minpsz:(0),				/* Min packet size accepted */
	mi_maxpsz:INFPSZ,			/* Max packet size accepted */
	mi_hiwat:(1),				/* Hi water mark */
	mi_lowat:(0),				/* Lo water mark */
};

STATIC int dl_open(queue_t *, dev_t *, int, int, cred_t *);
STATIC int dl_close(queue_t *, int, cred_t *);

STATIC struct qinit dl_xinit = {
	qi_qopen:dl_open,			/* Each open */
	qi_qclose:dl_close,			/* Last close */
	qi_minfo:&dl_xinfo,			/* Information */
};

STATIC struct streamtab dl_info = {
	st_rdinit:&dl_xinit,			/* Upper read queue */
	st_wrinit:&dl_xinit,			/* Upper write queue */
};

/*
 *  =========================================================================
 *
 *  OPEN AND CLOSE
 *
 *  =========================================================================
 */
STATIC char drvname[LIS_NAMESZ+9];
STATIC int dl_majors[256];
STATIC const char *dl_modules[256] = {
	"dl",
	"dl-dua",
	"dl-gr303",
	"dl-gr303ua",
	"dl-gsma",
	"dl-h225",
	"dl-iua",
	"dl-lapb",
	"dl-lapd",
	"dl-lapf",
	"dl-v52",
	"dl-v5ua",
};


/*
 *  =========================================================================
 *
 *  OPEN AND CLOSE
 *
 *  =========================================================================
 */
STATIC int dl_find_strdev(const char *devname)
{
	int i;
	for (i = 0; i < MAX_STRDEV; i++)
		if (lis_fstr_sw[i].f_str)
			if (strncmp(devname, lis_fstr_sw[i].f_name, LIS_NAMESZ) == 0)
				return (i);
	return (-1);
}

/*
 *  Open
 *  -------------------------------------------------------------------------
 *  This open function automatically loads the appropriate kernel modules and
 *  calls the appropriate driver for the minor device number opened.  Note
 *  that we do an lis_setq and call the actual driver's open function, so we
 *  should never return here.
 */
STATIC int dl_open(queue_t *q, dev_t *devp, int flag, int sflag, cred_t *crp)
{
	uchar cmajor;
	uchar cminor = getminor(*devp);
	const char *devname;
	struct streamtab *stab = NULL;
	int err;
	if (cminor == 0)
		return (ENOENT);	/* would loop */
	if ((cmajor = dl_majors[cminor])) {
		if (!(stab = lis_find_strdev(dl_majors[cminor])))
			cmajor = dl_majors[cminor] = 0;
		else if (strncmp(dl_modules[cminor], lis_fstr_sw[cmajor].f_name, LIS_NAMESZ) != 0) {
			/* name changed */
			stab = NULL;
			cmajor = dl_majors[cminor] = 0;
		}
	}
	if (!cmajor) {
		if (!(devname = dl_modules[cminor]))
			return (ENOENT);
		if ((err = dl_find_strdev(devname)) < 0) {
			sprintf(drvname, "streams-%s", devname);
			if ((err = request_module(drvname)))
				return (err < 0 ? -err : err);
			if ((err = dl_find_strdev(devname)) < 0)
				return (ENOENT);
		}
		cmajor = err;
	}
	if (!(stab = lis_find_strdev(cmajor)))
		return (ENOENT);
	lis_setq(q, stab->st_rdinit, stab->st_wrinit);
	if (!q->q_qinfo->qi_qopen) {
		swerr();
		return (EIO);
	}
	return (*q->q_qinfo->qi_qopen) (q, devp, flag, CLONEOPEN, crp);
}

/*
 *  Close
 *  -------------------------------------------------------------------------
 */
STATIC int dl_close(queue_t *q, int flag, cred_t *crp)
{
	(void) q;
	(void) flag;
	(void) crp;
	swerr();
	return (EIO);
}

/*
 *  =========================================================================
 *
 *  LIS MODULE INITIALIZATION
 *
 *  =========================================================================
 */
#define MODULE_STATIC STATIC
STATIC int dl_initialized = 0;
MODULE_STATIC void dl_init(void)
{
	int rtn;
	unless(dl_initialized, return);
	cmn_err(CE_NOTE, DL_BANNER);	/* console splash */
	if ((rtn = lis_register_strdev(dl_majors[0], &dl_info, 255, DL_DRV_NAME)) <= 0) {
		cmn_err(CE_PANIC, "%s: Cannot register major %d", DL_DRV_NAME, dl_majors[0]);
		dl_initialized = rtn;
		return;
	}
	dl_majors[0] = rtn;
	LIS_DEVFLAGS(rtn) |= LIS_MODFLG_CLONE;
	dl_initialized = 1;
	return;
}
MODULE_STATIC void dl_terminate(void)
{
	int rtn;
	if (dl_majors[0]) {
		if ((rtn = lis_unregister_strdev(dl_majors[0])))
			cmn_err(CE_PANIC, "%s: Cannot unregister major %d\n", DL_DRV_NAME, dl_majors[0]);
		dl_majors[0] = 0;
	}
	return;
}

/*
 *  =========================================================================
 *
 *  LINUX MODULE INITIALIZATION
 *
 *  =========================================================================
 */
int init_module(void)
{
	dl_init();
	if (dl_initialized < 0)
		return dl_initialized;
	return (0);
}
void cleanup_module(void)
{
	dl_terminate();
}