xref: /csrg-svn/sys/miscfs/specfs/specdev.h (revision 44523)
140654Smckusick /*
240654Smckusick  * Copyright (c) 1990 The Regents of the University of California.
340654Smckusick  * All rights reserved.
440654Smckusick  *
5*44523Sbostic  * %sccs.include.redist.c%
640654Smckusick  *
7*44523Sbostic  *	@(#)specdev.h	7.2 (Berkeley) 06/28/90
840654Smckusick  */
940654Smckusick 
1040654Smckusick /*
1140654Smckusick  * This structure defines the information maintained about
1240654Smckusick  * special devices. It is allocated in checkalias and freed
1340654Smckusick  * in vgone.
1440654Smckusick  */
1540654Smckusick struct specinfo {
1640654Smckusick 	struct	vnode **si_hashchain;
1740654Smckusick 	struct	vnode *si_specnext;
1840654Smckusick 	long	si_flags;
1940654Smckusick 	dev_t	si_rdev;
2040654Smckusick };
2140654Smckusick /*
2240654Smckusick  * Exported shorthand
2340654Smckusick  */
2440654Smckusick #define v_rdev v_specinfo->si_rdev
2540654Smckusick #define v_hashchain v_specinfo->si_hashchain
2640654Smckusick #define v_specnext v_specinfo->si_specnext
2740654Smckusick #define v_specflags v_specinfo->si_flags
2840654Smckusick 
2940654Smckusick /*
3040654Smckusick  * Flags for specinfo
3140654Smckusick  */
3240654Smckusick #define	SI_MOUNTEDON	0x0001	/* block special device is mounted on */
3340654Smckusick 
3440654Smckusick /*
3540654Smckusick  * Special device management
3640654Smckusick  */
3740654Smckusick #define	SPECHSZ	64
3840654Smckusick #if	((SPECHSZ&(SPECHSZ-1)) == 0)
3940654Smckusick #define	SPECHASH(rdev)	(((rdev>>5)+(rdev))&(SPECHSZ-1))
4040654Smckusick #else
4140654Smckusick #define	SPECHASH(rdev)	(((unsigned)((rdev>>5)+(rdev)))%SPECHSZ)
4240654Smckusick #endif
4340654Smckusick 
4440654Smckusick struct vnode *speclisth[SPECHSZ];
45