Return to dmapi_sysent.c CVS log

Up to [Development] / linux-2.6-xfs / fs / dmapi

set MOD_INC_USE_COUNT, and do not unset it unless dm_uninit gives an okay.
Also, deregister our device.

/*
 * Copyright (c) 2000 Silicon Graphics, Inc.  All Rights Reserved.
 * 
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 * 
 * This program is distributed in the hope that it would be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * 
 * Further, this software is distributed without any warranty that it is
 * free of the rightful claim of any third person regarding infringement
 * or the like.  Any license provided herein, whether implied or
 * otherwise, applies only to this software file.  Patent licenses, if
 * any, provided herein do not apply to combinations of this program with
 * other software, or any other product whatsoever.
 * 
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write the Free Software Foundation, Inc., 59
 * Temple Place - Suite 330, Boston MA 02111-1307, USA.
 * 
 * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
 * Mountain View, CA  94043, or:
 * 
 * http://www.sgi.com 
 * 
 * For further information regarding this notice, see: 
 * 
 * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
 */

/* Data Migration API (DMAPI)
 */


/* We're using MISC_MAJOR / DMAPI_MINOR. */
/*  mknod /dev/dmapi c 10 140  */

#include <linux/kernel.h>
#include <linux/miscdevice.h>
#include <linux/init.h>

#include <asm/uaccess.h>

#include "dmapi_private.h"

void dm_init(void);
int dm_uninit(void);

static int
dmapi_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
	    unsigned long arg)
{
	sys_dmapi_args_t kargs;
	sys_dmapi_args_t *uap = &kargs;
	int error = 0;
	int rvp = -ENOSYS;
	int use_rvp = 0;

	if (!capable(CAP_MKNOD))
		return(-EPERM);

	if( copy_from_user( &kargs, (sys_dmapi_args_t*)arg,
			   sizeof(sys_dmapi_args_t) ) )
		return -EFAULT;

	switch (cmd) {
	case DM_CLEAR_INHERIT:
		error = dm_clear_inherit(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(dm_attrname_t *) uap->arg5);	/* attrnamep */
		break;
	case DM_CREATE_BY_HANDLE:
		error = dm_create_by_handle(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* dirhanp */
				(size_t)	uap->arg3,	/* dirhlen */
				(dm_token_t)	uap->arg4,	/* token */
				(void *)	uap->arg5,	/* hanp */
				(size_t)	uap->arg6,	/* hlen */
				(char *)	uap->arg7);	/* cname */
		break;
	case DM_CREATE_SESSION:
		error = dm_create_session(
				(dm_sessid_t)	uap->arg1,	/* oldsid */
				(char *)	uap->arg2,	/* sessinfop */
				(dm_sessid_t *)	uap->arg3);	/* newsidp */
		break;
	case DM_CREATE_USEREVENT:
		error = dm_create_userevent(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(size_t)	uap->arg2,	/* msglen */
				(void *)	uap->arg3,	/* msgdatap */
				(dm_token_t *)	uap->arg4);	/* tokenp */
		break;
	case DM_DESTROY_SESSION:
		error = dm_destroy_session(
				(dm_sessid_t)	uap->arg1);	/* sid */
		break;
	case DM_DOWNGRADE_RIGHT:
		error = dm_downgrade_right(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4);	/* token */
		break;
	case DM_FD_TO_HANDLE:
		error = dm_fd_to_hdl(
				(int)		uap->arg1,	/* fd */
				(void *)	uap->arg2,	/* hanp */
				(size_t *)	uap->arg3);	/* hlenp */
		break;
	case DM_FIND_EVENTMSG:
		error = dm_find_eventmsg(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(dm_token_t)	uap->arg2,	/* token */
				(size_t)	uap->arg3,	/* buflen */
				(void *)	uap->arg4,	/* bufp */
				(size_t *)	uap->arg5);	/* rlenp */
		break;
	case DM_GET_ALLOCINFO:
		use_rvp = 1;
		error = dm_get_allocinfo_rvp(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(dm_off_t *)	uap->arg5,	/* offp */
				(u_int)		uap->arg6,	/* nelem */
				(dm_extent_t *)	uap->arg7,	/* extentp */
				(u_int *)	uap->arg8,	/* nelemp */
						&rvp);
		break;
	case DM_GET_BULKALL:
		use_rvp = 1;
		error = dm_get_bulkall_rvp(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(u_int)		uap->arg5,	/* mask */
				(dm_attrname_t *) uap->arg6,	/* attrnamep */
				(dm_attrloc_t *) uap->arg7,	/* locp */
				(size_t)	uap->arg8,	/* buflen */
				(void *)	uap->arg9,	/* bufp */
				(size_t *)	uap->arg10,	/* rlenp */
						&rvp);
		break;
	case DM_GET_BULKATTR:
		use_rvp = 1;
		error = dm_get_bulkattr_rvp(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(u_int)		uap->arg5,	/* mask */
				(dm_attrloc_t *)uap->arg6,	/* locp */
				(size_t)	uap->arg7,	/* buflen */
				(void *)	uap->arg8,	/* bufp */
				(size_t *)	uap->arg9,	/* rlenp */
						&rvp);
		break;
	case DM_GET_CONFIG:
		error = dm_get_config(
				(void *)	uap->arg1,	/* hanp */
				(size_t)	uap->arg2,	/* hlen */
				(dm_config_t)	uap->arg3,	/* flagname */
				(dm_size_t *)	uap->arg4);	/* retvalp */
		break;
	case DM_GET_CONFIG_EVENTS:
		error = dm_get_config_events(
				(void *)	uap->arg1,	/* hanp */
				(size_t)	uap->arg2,	/* hlen */
				(u_int)		uap->arg3,	/* nelem */
				(dm_eventset_t *) uap->arg4,	/* eventsetp */
				(u_int *)	uap->arg5);	/* nelemp */
		break;
	case DM_GET_DIOINFO:
		error = dm_get_dioinfo(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(dm_dioinfo_t *)uap->arg5);	/* diop */
		break;
	case DM_GET_DIRATTRS:
		use_rvp = 1;
		error = dm_get_dirattrs_rvp(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(u_int)		uap->arg5,	/* mask */
				(dm_attrloc_t *)uap->arg6,	/* locp */
				(size_t)	uap->arg7,	/* buflen */
				(void *)	uap->arg8,	/* bufp */
				(size_t *)	uap->arg9,	/* rlenp */
						&rvp);
		break;
	case DM_GET_DMATTR:
		error = dm_get_dmattr(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(dm_attrname_t *) uap->arg5,	/* attrnamep */
				(size_t)	uap->arg6,	/* buflen */
				(void *)	uap->arg7,	/* bufp */
				(size_t *)	uap->arg8);	/* rlenp */

		break;
	case DM_GET_EVENTLIST:
		error = dm_get_eventlist(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(u_int)		uap->arg5,	/* nelem */
				(dm_eventset_t *) uap->arg6,	/* eventsetp */
				(u_int *)	uap->arg7);	/* nelemp */
		break;
	case DM_GET_EVENTS:
		error = dm_get_events(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(u_int)		uap->arg2,	/* maxmsgs */
				(u_int)		uap->arg3,	/* flags */
				(size_t)	uap->arg4,	/* buflen */
				(void *)	uap->arg5,	/* bufp */
				(size_t *)	uap->arg6);	/* rlenp */
		break;
	case DM_GET_FILEATTR:
		error = dm_get_fileattr(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(u_int)		uap->arg5,	/* mask */
				(dm_stat_t *)	uap->arg6);	/* statp */
		break;
	case DM_GET_MOUNTINFO:
		error = dm_get_mountinfo(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(size_t)	uap->arg5,	/* buflen */
				(void *)	uap->arg6,	/* bufp */
				(size_t *)	uap->arg7);	/* rlenp */
		break;
	case DM_GET_REGION:
		error = dm_get_region(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(u_int)		uap->arg5,	/* nelem */
				(dm_region_t *)	uap->arg6,	/* regbufp */
				(u_int *)	uap->arg7);	/* nelemp */
		break;
	case DM_GETALL_DISP:
		error = dm_getall_disp(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(size_t)	uap->arg2,	/* buflen */
				(void *)	uap->arg3,	/* bufp */
				(size_t *)	uap->arg4);	/* rlenp */
		break;
	case DM_GETALL_DMATTR:
		error = dm_getall_dmattr(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(size_t)	uap->arg5,	/* buflen */
				(void *)	uap->arg6,	/* bufp */
				(size_t *)	uap->arg7);	/* rlenp */
		break;
	case DM_GETALL_INHERIT:
		error = dm_getall_inherit(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(u_int)		uap->arg5,	/* nelem */
				(dm_inherit_t *)uap->arg6,	/* inheritbufp*/
				(u_int *)	uap->arg7);	/* nelemp */
		break;
	case DM_GETALL_SESSIONS:
		error = dm_getall_sessions(
				(u_int)		uap->arg1,	/* nelem */
				(dm_sessid_t *)	uap->arg2,	/* sidbufp */
				(u_int *)	uap->arg3);	/* nelemp */
		break;
	case DM_GETALL_TOKENS:
		error = dm_getall_tokens(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(u_int)		uap->arg2,	/* nelem */
				(dm_token_t *)	uap->arg3,	/* tokenbufp */
				(u_int *)	uap->arg4);	/* nelemp */
		break;
	case DM_INIT_ATTRLOC:
		error = dm_init_attrloc(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(dm_attrloc_t *) uap->arg5);	/* locp */
		break;
	case DM_MKDIR_BY_HANDLE:
		error = dm_mkdir_by_handle(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* dirhanp */
				(size_t)	uap->arg3,	/* dirhlen */
				(dm_token_t)	uap->arg4,	/* token */
				(void *)	uap->arg5,	/* hanp */
				(size_t)	uap->arg6,	/* hlen */
				(char *)	uap->arg7);	/* cname */
		break;
	case DM_MOVE_EVENT:
		error = dm_move_event(
				(dm_sessid_t)	uap->arg1,	/* srcsid */
				(dm_token_t)	uap->arg2,	/* token */
				(dm_sessid_t)	uap->arg3,	/* targetsid */
				(dm_token_t *)	uap->arg4);	/* rtokenp */
		break;
	case DM_OBJ_REF_HOLD:
		error = dm_obj_ref_hold(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(dm_token_t)	uap->arg2,	/* token */
				(void *)	uap->arg3,	/* hanp */
				(size_t)	uap->arg4);	/* hlen */
		break;
	case DM_OBJ_REF_QUERY:
		use_rvp = 1;
		error = dm_obj_ref_query_rvp(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(dm_token_t)	uap->arg2,	/* token */
				(void *)	uap->arg3,	/* hanp */
				(size_t)	uap->arg4,	/* hlen */
						&rvp);
		break;
	case DM_OBJ_REF_RELE:
		error = dm_obj_ref_rele(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(dm_token_t)	uap->arg2,	/* token */
				(void *)	uap->arg3,	/* hanp */
				(size_t)	uap->arg4);	/* hlen */
		break;
	case DM_PATH_TO_FSHANDLE:
		error = dm_path_to_fshdl(
				(char *)	uap->arg1,	/* path */
				(void *)	uap->arg2,	/* hanp */
				(size_t *)	uap->arg3);	/* hlenp */
		break;
	case DM_PATH_TO_HANDLE:
		error = dm_path_to_hdl(
				(char *)	uap->arg1,	/* path */
				(void *)	uap->arg2,	/* hanp */
				(size_t *)	uap->arg3);	/* hlenp */
		break;
	case DM_PENDING:
		error = dm_pending(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(dm_token_t)	uap->arg2,	/* token */
				(dm_timestruct_t *) uap->arg3);	/* delay */
		break;
	case DM_PROBE_HOLE:
		error = dm_probe_hole(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(dm_off_t)	uap->arg5,	/* off */
				(dm_size_t)	uap->arg6,	/* len */
				(dm_off_t *)	uap->arg7,	/* roffp */
				(dm_size_t *)	uap->arg8);	/* rlenp */
		break;
	case DM_PUNCH_HOLE:
		error = dm_punch_hole(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(dm_off_t)	uap->arg5,	/* off */
				(dm_size_t)	uap->arg6);	/* len */
		break;
	case DM_QUERY_RIGHT:
		error = dm_query_right(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(dm_right_t *)	uap->arg5);	/* rightp */
		break;
	case DM_QUERY_SESSION:
		error = dm_query_session(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(size_t)	uap->arg2,	/* buflen */
				(void *)	uap->arg3,	/* bufp */
				(size_t *)	uap->arg4);	/* rlenp */
		break;
	case DM_READ_INVIS:
		use_rvp = 1;
		error = dm_read_invis_rvp(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(dm_off_t)	uap->arg5,	/* off */
				(dm_size_t)	uap->arg6,	/* len */
				(void *)	uap->arg7,	/* bufp */
						&rvp);
		break;
	case DM_RELEASE_RIGHT:
		error = dm_release_right(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4);	/* token */
		break;
	case DM_REMOVE_DMATTR:
		error = dm_remove_dmattr(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(int)		uap->arg5,	/* setdtime */
				(dm_attrname_t *) uap->arg6);	/* attrnamep */
		break;
	case DM_REQUEST_RIGHT:
		error = dm_request_right(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(u_int)		uap->arg5,	/* flags */
				(dm_right_t)	uap->arg6);	/* right */
		break;
	case DM_RESPOND_EVENT:
		error = dm_respond_event(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(dm_token_t)	uap->arg2,	/* token */
				(dm_response_t)	uap->arg3,	/* response */
				(int)		uap->arg4,	/* reterror */
				(size_t)	uap->arg5,	/* buflen */
				(void *)	uap->arg6);	/* respbufp */
		break;
	case DM_SEND_MSG:
		error = dm_send_msg(
				(dm_sessid_t)	uap->arg1,	/* targetsid */
				(dm_msgtype_t)	uap->arg2,	/* msgtype */
				(size_t)	uap->arg3,	/* buflen */
				(void *)	uap->arg4);	/* bufp */
		break;
	case DM_SET_DISP:
		error = dm_set_disp(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(dm_eventset_t *) uap->arg5,	/* eventsetp */
				(u_int)		uap->arg6);	/* maxevent */
		break;
	case DM_SET_DMATTR:
		error = dm_set_dmattr(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(dm_attrname_t *) uap->arg5,	/* attrnamep */
				(int)		uap->arg6,	/* setdtime */
				(size_t)	uap->arg7,	/* buflen */
				(void *)	uap->arg8);	/* bufp */
		break;
	case DM_SET_EVENTLIST:
		error = dm_set_eventlist(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(dm_eventset_t *) uap->arg5,	/* eventsetp */
				(u_int)		uap->arg6);	/* maxevent */
		break;
	case DM_SET_FILEATTR:
		error = dm_set_fileattr(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(u_int)		uap->arg5,	/* mask */
				(dm_fileattr_t *)uap->arg6);	/* attrp */
		break;
	case DM_SET_INHERIT:
		error = dm_set_inherit(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(dm_attrname_t *)uap->arg5,	/* attrnamep */
				(mode_t)	uap->arg6);	/* mode */
		break;
	case DM_SET_REGION:
		error = dm_set_region(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(u_int)		uap->arg5,	/* nelem */
				(dm_region_t *)	uap->arg6,	/* regbufp */
				(dm_boolean_t *) uap->arg7);	/* exactflagp */
		break;
	case DM_SET_RETURN_ON_DESTROY:
		error = dm_set_return_on_destroy(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(dm_attrname_t *) uap->arg5,	/* attrnamep */
				(dm_boolean_t)	uap->arg6);	/* enable */
		break;
	case DM_SYMLINK_BY_HANDLE:
		error = dm_symlink_by_handle(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* dirhanp */
				(size_t)	uap->arg3,	/* dirhlen */
				(dm_token_t)	uap->arg4,	/* token */
				(void *)	uap->arg5,	/* hanp */
				(size_t)	uap->arg6,	/* hlen */
				(char *)	uap->arg7,	/* cname */
				(char *)	uap->arg8);	/* path */
		break;
	case DM_SYNC_BY_HANDLE:
		error = dm_sync_by_handle(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4);	/* token */
		break;
	case DM_UPGRADE_RIGHT:
		error = dm_upgrade_right(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4);	/* token */
		break;
	case DM_WRITE_INVIS:
		use_rvp = 1;
		error = dm_write_invis_rvp(
				(dm_sessid_t)	uap->arg1,	/* sid */
				(void *)	uap->arg2,	/* hanp */
				(size_t)	uap->arg3,	/* hlen */
				(dm_token_t)	uap->arg4,	/* token */
				(int)		uap->arg5,	/* flags */
				(dm_off_t)	uap->arg6,	/* off */
				(dm_size_t)	uap->arg7,	/* len */
				(void *)	uap->arg8,	/* bufp */
						&rvp);
		break;
	default:
		error = ENOSYS;
		break;
	}
	/* If it was an *_rvp() function, then
		if error==0, return |rvp|
	*/
	if( use_rvp && (error == 0) )
		return rvp;
	else
		return -error;
}


/* XXX a debugging tool */
/* use 'cat /dev/dmapi' to get dump of info */
static ssize_t
dmapi_dump(struct file *file, char *buf, size_t count, loff_t *ppos)
{
	char tmp[1024];
	int l, len;

	extern u_int dm_sessions_active;
	extern dm_sessid_t dm_next_sessid;
	extern dm_token_t dm_next_token;
	extern dm_sequence_t dm_next_sequence;
	extern int dm_fsys_cnt;

	if( *ppos == 0 ){
		l = sprintf( tmp, "# " DM_VER_STR_CONTENTS "\n"
			    "dm_sessions_active=%u\n"
			    "dm_next_sessid=%d\n"
			    "dm_next_token=%d\n"
			    "dm_next_sequence=%u\n"
			    "dm_fsys_cnt=%d\n",
				dm_sessions_active,
				(int)dm_next_sessid,
				(int)dm_next_token,
				(u_int)dm_next_sequence,
				dm_fsys_cnt );
	}
	else {
		return 0;
	}
#define min(a,b) (((a)<(b))?(a):(b))
	len = min(l,count);
#undef min

	if( copy_to_user(buf, tmp, len) )
		return -EFAULT;
	*ppos += 1;
	return len;
}


static int
dmapi_open(struct inode *inode, struct file *file)
{
	return 0;
}


static int
dmapi_release(struct inode *inode, struct file *file)
{
	return 0;
}


static struct file_operations dmapi_fops = {
	open:		dmapi_open,
	ioctl:		dmapi_ioctl,
	read:		dmapi_dump,
	release:	dmapi_release
};

static struct miscdevice dmapi_dev = {
	minor:	DMAPI_MINOR,
	name:	"dmapi",
	fops:	&dmapi_fops
};

void dmapi_init(void)
{
	int ret;

	ret = misc_register(&dmapi_dev);
	if( ret != 0 )
		printk(KERN_ERR "dmapi_init: misc_register returned %d\n", ret);
	MOD_INC_USE_COUNT;
	dm_init();
}

void dmapi_uninit(void)
{
	if( dm_uninit() == 0 ){
		MOD_DEC_USE_COUNT;
		misc_deregister(&dmapi_dev);
	}
}