/*  * This file is part of the UCB release of Plan 9. It is subject to the license * terms in the LICENSE file found in the top-level directory of this * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No * part of the UCB release of Plan 9, including this file, may be copied, * modified, propagated, or distributed except according to the terms contained * in the LICENSE file. */ #include	"all.h" Dentry*getdir(Iobuf *p, int slot){	Dentry *d; 	if(!p)		return 0;	d = (Dentry*)p->iobuf + slot%DIRPERBUF;	return d;} voidaccessdir(Iobuf *p, Dentry *d, int f){	long t; 	if(p && !isro(p->dev)) {		if(!(f & (FWRITE|FWSTAT)) && noatime)			return;		t = time(nil);		if(f & (FREAD|FWRITE|FWSTAT)){			d->atime = t;			p->flags |= Bmod;		}		if(f & FWRITE) {			d->mtime = t;			d->qid.version++;			p->flags |= Bmod;		}	}} voiddbufread(Iobuf *p, Dentry *d, long a){	USED(p, d, a);} longrel2abs(Iobuf *p, Dentry *d, long a, int tag, int putb){	long addr, qpath;	Device dev; 	if(a < 0) {		print("dnodebuf: neg\n");		return 0;	}	qpath = d->qid.path;	dev = p->dev;	if(a < NDBLOCK) {		addr = d->dblock[a];		if(!addr && tag) {			addr = balloc(dev, tag, qpath);			d->dblock[a] = addr;			p->flags |= Bmod|Bimm;		}		if(putb)			putbuf(p);		return addr;	}	a -= NDBLOCK;	if(a < INDPERBUF) {		addr = d->iblock;		if(!addr && tag) {			addr = balloc(dev, Tind1, qpath);			d->iblock = addr;			p->flags |= Bmod|Bimm;		}		if(putb)			putbuf(p);		addr = indfetch(p, d, addr, a, Tind1, tag);		return addr;	}	a -= INDPERBUF;	if(a < INDPERBUF2) {		addr = d->diblock;		if(!addr && tag) {			addr = balloc(dev, Tind2, qpath);			d->diblock = addr;			p->flags |= Bmod|Bimm;		}		if(putb)			putbuf(p);		addr = indfetch(p, d, addr, a/INDPERBUF, Tind2, Tind1);		addr = indfetch(p, d, addr, a%INDPERBUF, Tind1, tag);		return addr;	}	if(putb)		putbuf(p);	print("dnodebuf: trip indirect\n");	return 0;} Iobuf*dnodebuf(Iobuf *p, Dentry *d, long a, int tag){	long addr; 	addr = rel2abs(p, d, a, tag, 0);	if(addr)		return getbuf(p->dev, addr, Bread);	return 0;} /* * same as dnodebuf but it calls putpuf(p) * to reduce interference. */Iobuf*dnodebuf1(Iobuf *p, Dentry *d, long a, int tag){	long addr;	Device dev; 	dev = p->dev;	addr = rel2abs(p, d, a, tag, 1);	if(addr)		return getbuf(dev, addr, Bread);	return 0; } longindfetch(Iobuf *p, Dentry *d, long addr, long a, int itag, int tag){	Iobuf *bp; 	if(!addr)		return 0;	bp = getbuf(p->dev, addr, Bread);	if(!bp || checktag(bp, itag, d->qid.path)) {		if(!bp) {			print("ind fetch bp = 0\n");			return 0;		}		print("ind fetch tag\n");		putbuf(bp);		return 0;	}	addr = ((long*)bp->iobuf)[a];	if(!addr && tag) {		addr = balloc(p->dev, tag, d->qid.path);		if(addr) {			((long*)bp->iobuf)[a] = addr;			bp->flags |= Bmod;			if(localfs || tag == Tdir)				bp->flags |= Bimm;			settag(bp, itag, d->qid.path);		}	}	putbuf(bp);	return addr;} voiddtrunc(Iobuf *p, Dentry *d){	int i; 	bfree(p->dev, d->diblock, 2);	d->diblock = 0;	bfree(p->dev, d->iblock, 1);	d->iblock = 0;	for(i=NDBLOCK-1; i>=0; i--) {		bfree(p->dev, d->dblock[i], 0);		d->dblock[i] = 0;	}	d->size = 0;	p->flags |= Bmod|Bimm;	accessdir(p, d, FWRITE);}