/* $NetBSD: blist.h,v 1.8 2013/12/09 09:35:17 wiz Exp $ */ /*- * Copyright (c) 1998 Matthew Dillon. All Rights Reserved. * 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. * 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 AUTHOR ``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 AUTHOR 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. */ /* * Implements bitmap resource lists. * * Usage: * blist = blist_create(blocks) * (void) blist_destroy(blist) * blkno = blist_alloc(blist, count) * (void) blist_free(blist, blkno, count) * nblks = blist_fill(blist, blkno, count) * (void) blist_resize(&blist, count, freeextra) * * * Notes: * on creation, the entire list is marked reserved. You should * first blist_free() the sections you want to make available * for allocation before doing general blist_alloc()/free() * ops. * * BLIST_NONE is returned on failure. This module is typically * capable of managing up to (2^31) blocks per blist, though * the memory utilization would be insane if you actually did * that. Managing something like 512MB worth of 4K blocks * eats around 32 KBytes of memory. * * $FreeBSD: src/sys/sys/blist.h,v 1.9 2005/01/07 02:29:23 imp Exp $ */ #ifndef _SYS_BLIST_H_ #define _SYS_BLIST_H_ /* * for space efficiency, sizeof(blist_bitmap_t) should be * greater than or equal to sizeof(blist_blkno_t). */ typedef uint32_t blist_bitmap_t; typedef uint32_t blist_blkno_t; /* * note: currently use BLIST_NONE as an absolute value rather than * a flag bit. */ #define BLIST_NONE ((blist_blkno_t)-1) typedef struct blist *blist_t; #define BLIST_BMAP_RADIX (sizeof(blist_bitmap_t)*8) #define BLIST_MAX_ALLOC BLIST_BMAP_RADIX extern blist_t blist_create(blist_blkno_t blocks); extern void blist_destroy(blist_t blist); extern blist_blkno_t blist_alloc(blist_t blist, blist_blkno_t count); extern void blist_free(blist_t blist, blist_blkno_t blkno, blist_blkno_t count); extern blist_blkno_t blist_fill(blist_t bl, blist_blkno_t blkno, blist_blkno_t count); extern void blist_print(blist_t blist); extern void blist_resize(blist_t *pblist, blist_blkno_t count, int freenew); #endif /* _SYS_BLIST_H_ */ |