freebsd-skq/sys/sys/mdioctl.h
Matthew Dillon 447deba3da Fix a bug in the block number calculation for VN disks with a sector
size != 512 that are configured without a label.  The bug should only
    have effected swap-backed VN mounts without a label.

    Add several major features to VN.  In the kernel we add a swap
    pre-reservation capability, which can be used to guarentee seek
    consistency for swap-backed VN nodes.  This also incidently allows
    a swap-backed VN filesystem to be recovered after a crash in some
    cases (if the same swap blocks happen to be reserved).

    We also add a number of new options to vnconfig which do the work
    of pre-zeroing or creating/truncating/extending a file which greatly
    simplifies using VN in a file-backed configuration.

    Add FreeBSD CVS label to sys/sys/vnioctl.h, as well as a new ioctl
    flag for the swap pre-reservation feature.

Reviewed by:	Alan Cox <alc@cs.rice.edu>, David Greenman <dg@root.com>
1999-09-17 05:34:00 +00:00

80 lines
3.3 KiB
C

/*
* Copyright (c) 1988 University of Utah.
* Copyright (c) 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* the Systems Programming Group of the University of Utah Computer
* Science Department.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* from: Utah $Hdr: fdioctl.h 1.1 90/07/09$
*
* @(#)vnioctl.h 8.1 (Berkeley) 6/10/93
*
* $FreeBSD$
*/
#ifndef _SYS_VNIOCTL_H_
#define _SYS_VNIOCTL_H_
/*
* Ioctl definitions for file (vnode) disk pseudo-device.
*/
#define _PATH_VNTAB "/etc/vntab" /* default config file */
struct vn_ioctl {
char *vn_file; /* pathname of file to mount */
int vn_size; /* (returned) size of disk */
};
/*
* Before you can use a unit, it must be configured with VNIOCSET.
* The configuration persists across opens and closes of the device;
* an VNIOCCLR must be used to reset a configuration. An attempt to
* VNIOCSET an already active unit will return EBUSY.
*/
#define VNIOCATTACH _IOWR('F', 0, struct vn_ioctl) /* attach file */
#define VNIOCDETACH _IOWR('F', 1, struct vn_ioctl) /* detach disk */
#define VNIOCGSET _IOWR('F', 2, u_long ) /* set global option */
#define VNIOCGCLEAR _IOWR('F', 3, u_long ) /* reset --//-- */
#define VNIOCUSET _IOWR('F', 4, u_long ) /* set unit option */
#define VNIOCUCLEAR _IOWR('F', 5, u_long ) /* reset --//-- */
#define VN_LABELS 0x1 /* Use disk(/slice) labels */
#define VN_FOLLOW 0x2 /* Debug flow in vn driver */
#define VN_DEBUG 0x4 /* Debug data in vn driver */
#define VN_IO 0x8 /* Debug I/O in vn driver */
#define VN_DONTCLUSTER 0x10 /* Don't cluster */
#define VN_RESERVE 0x20 /* Pre-reserve swap */
#endif /* _SYS_VNIOCTL_H_*/