xref: /freebsd-10-stable/sys/sys/disk.h

/*-
 * ----------------------------------------------------------------------------
 * "THE BEER-WARE LICENSE" (Revision 42):
 * <phk@FreeBSD.ORG> wrote this file.  As long as you retain this notice you
 * can do whatever you want with this stuff. If we meet some day, and you think
 * this stuff is worth it, you can buy me a beer in return.   Poul-Henning Kamp
 * ----------------------------------------------------------------------------
 *
 * $FreeBSD: head/sys/sys/disk.h 210226 2010-07-18 20:57:53Z trasz $
 *
 */

#ifndef _SYS_DISK_H_
#define	_SYS_DISK_H_

#include <sys/ioccom.h>

#ifdef _KERNEL

#ifndef _SYS_CONF_H_
#include <sys/conf.h>	/* XXX: temporary to avoid breakage */
#endif

void disk_err(struct bio *bp, const char *what, int blkdone, int nl);

#endif

#define DIOCGSECTORSIZE	_IOR('d', 128, u_int)
	/*-
	 * Get the sectorsize of the device in bytes.  The sectorsize is the
	 * smallest unit of data which can be transfered from this device.
	 * Usually this is a power of two but it may not be. (ie: CDROM audio)
	 */

#define DIOCGMEDIASIZE	_IOR('d', 129, off_t)	/* Get media size in bytes */
	/*-
	 * Get the size of the entire device in bytes.  This should be a
	 * multiple of the sectorsize.
	 */

#define DIOCGFWSECTORS	_IOR('d', 130, u_int)	/* Get firmware sectorcount */
	/*-
	 * Get the firmwares notion of number of sectors per track.  This
	 * value is mostly used for compatibility with various ill designed
	 * disk label formats.  Don't use it unless you have to.
	 */

#define DIOCGFWHEADS	_IOR('d', 131, u_int)	/* Get firmware headcount */
	/*-
	 * Get the firmwares notion of number of heads per cylinder.  This
	 * value is mostly used for compatibility with various ill designed
	 * disk label formats.  Don't use it unless you have to.
	 */

#define DIOCSKERNELDUMP _IOW('d', 133, u_int)	/* Set/Clear kernel dumps */
	/*-
	 * Enable/Disable (the argument is boolean) the device for kernel
	 * core dumps.
	 */

#define DIOCGFRONTSTUFF _IOR('d', 134, off_t)
	/*-
	 * Many disk formats have some amount of space reserved at the
	 * start of the disk to hold bootblocks, various disklabels and
	 * similar stuff.  This ioctl returns the number of such bytes
	 * which may apply to the device.
	 */

#define	DIOCGFLUSH _IO('d', 135)		/* Flush write cache */
	/*-
	 * Flush write cache of the device.
	 */

#define	DIOCGDELETE _IOW('d', 136, off_t[2])	/* Delete data */
	/*-
	 * Mark data on the device as unused.
	 */

#define	DISK_IDENT_SIZE	256
#define	DIOCGIDENT _IOR('d', 137, char[DISK_IDENT_SIZE])
	/*-
	 * Get the ident of the given provider. Ident is (most of the time)
	 * a uniqe and fixed provider's identifier. Ident's properties are as
	 * follow:
	 * - ident value is preserved between reboots,
	 * - provider can be detached/attached and ident is preserved,
	 * - provider's name can change - ident can't,
	 * - ident value should not be based on on-disk metadata; in other
	 *   words copying whole data from one disk to another should not
	 *   yield the same ident for the other disk,
	 * - there could be more than one provider with the same ident, but
	 *   only if they point at exactly the same physical storage, this is
	 *   the case for multipathing for example,
	 * - GEOM classes that consumes single providers and provide single
	 *   providers, like geli, gbde, should just attach class name to the
	 *   ident of the underlying provider,
	 * - ident is an ASCII string (is printable),
	 * - ident is optional and applications can't relay on its presence.
	 */

#define DIOCGPROVIDERNAME _IOR('d', 138, char[MAXPATHLEN])
	/*-
	 * Store the provider name, given a device path, in a buffer. The buffer
	 * must be at least MAXPATHLEN bytes long.
	 */

#define DIOCGSTRIPESIZE	_IOR('d', 139, off_t)	/* Get stripe size in bytes */
	/*-
	 * Get the size of the device's optimal access block in bytes.
	 * This should be a multiple of the sectorsize.
	 */

#define DIOCGSTRIPEOFFSET _IOR('d', 140, off_t)	/* Get stripe offset in bytes */
	/*-
	 * Get the offset of the first device's optimal access block in bytes.
	 * This should be a multiple of the sectorsize.
	 */

#endif /* _SYS_DISK_H_ */