示例#1
0
static Chan*
sdattach(char* spec)
{
	Chan *c;
	char *p;
	SDev *sdev;
	int idno, subno;

	if(*spec == '\0'){
		c = devattach(sddevtab.dc, spec);
		mkqid(&c->qid, QID(0, 0, 0, Qtopdir), 0, QTDIR);
		return c;
	}

	if(spec[0] != 's' || spec[1] != 'd')
		error(Ebadspec);
	idno = spec[2];
	subno = strtol(&spec[3], &p, 0);
	if(p == &spec[3])
		error(Ebadspec);

	if((sdev=sdgetdev(idno)) == nil)
		error(Enonexist);
	if(sdgetunit(sdev, subno) == nil){
		decref(&sdev->r);
		error(Enonexist);
	}

	c = devattach(sddevtab.dc, spec);
	mkqid(&c->qid, QID(sdev->idno, subno, 0, Qunitdir), 0, QTDIR);
	c->dev = (sdev->idno << UnitLOG) + subno;
	decref(&sdev->r);
	return c;
}
示例#2
0
文件: devsd.c 项目: Akheon23/nix-os
static SDunit*
sdindex2unit(int index)
{
	SDev *sdev;

	/*
	 * Associate a unit with a given index into the top-level
	 * device directory.
	 * The device will be probed if it has not already been
	 * successfully accessed.
	 */
	for(sdev = sdlist; sdev != nil; sdev = sdev->next){
		if(index >= sdev->index && index < sdev->index+sdev->nunit)
			return sdgetunit(sdev, index-sdev->index);
	}

	return nil;
}
示例#3
0
static int
sdgen(Chan* c, char*, Dirtab*, int, int s, Dir* dp)
{
	Qid q;
	uvlong l;
	int i, r;
	SDpart *pp;
	SDunit *unit;
	SDev *sdev;

	switch(TYPE(c->qid)){
	case Qtopdir:
		if(s == DEVDOTDOT){
			mkqid(&q, QID(0, 0, 0, Qtopdir), 0, QTDIR);
			snprint(up->genbuf, sizeof up->genbuf, "#%C",
				sddevtab.dc);
			devdir(c, q, up->genbuf, 0, eve, 0555, dp);
			return 1;
		}

		if(s+Qtopbase < Qunitdir)
			return sd1gen(c, s+Qtopbase, dp);
		s -= (Qunitdir-Qtopbase);

		qlock(&devslock);
		for(i=0; i<nelem(devs); i++){
			if(devs[i]){
				if(s < devs[i]->nunit)
					break;
				s -= devs[i]->nunit;
			}
		}

		if(i == nelem(devs)){
			/* Run off the end of the list */
			qunlock(&devslock);
			return -1;
		}

		if((sdev = devs[i]) == nil){
			qunlock(&devslock);
			return 0;
		}

		incref(&sdev->r);
		qunlock(&devslock);

		if((unit = sdev->unit[s]) == nil)
			if((unit = sdgetunit(sdev, s)) == nil){
				decref(&sdev->r);
				return 0;
			}

		mkqid(&q, QID(sdev->idno, s, 0, Qunitdir), 0, QTDIR);
		if(emptystr(unit->user))
			kstrdup(&unit->user, eve);
		devdir(c, q, unit->name, 0, unit->user, unit->perm, dp);
		decref(&sdev->r);
		return 1;

	case Qunitdir:
		if(s == DEVDOTDOT){
			mkqid(&q, QID(0, 0, 0, Qtopdir), 0, QTDIR);
			snprint(up->genbuf, sizeof up->genbuf, "#%C",
				sddevtab.dc);
			devdir(c, q, up->genbuf, 0, eve, 0555, dp);
			return 1;
		}

		if((sdev = sdgetdev(DEV(c->qid))) == nil){
			devdir(c, c->qid, "unavailable", 0, eve, 0, dp);
			return 1;
		}

		unit = sdev->unit[UNIT(c->qid)];
		qlock(&unit->ctl);

		/*
		 * Check for media change.
		 * If one has already been detected, sectors will be zero.
		 * If there is one waiting to be detected, online
		 * will return > 1.
		 * Online is a bit of a large hammer but does the job.
		 */
		if(unit->sectors == 0
		|| (unit->dev->ifc->online && unit->dev->ifc->online(unit) > 1))
			sdinitpart(unit);

		i = s+Qunitbase;
		if(i < Qpart){
			r = sd2gen(c, i, dp);
			qunlock(&unit->ctl);
			decref(&sdev->r);
			return r;
		}
		i -= Qpart;
		if(unit->part == nil || i >= unit->npart){
			qunlock(&unit->ctl);
			decref(&sdev->r);
			break;
		}
		pp = &unit->part[i];
		if(!pp->valid){
			qunlock(&unit->ctl);
			decref(&sdev->r);
			return 0;
		}
		l = (pp->end - pp->start) * unit->secsize;
		mkqid(&q, QID(DEV(c->qid), UNIT(c->qid), i, Qpart),
			unit->vers+pp->vers, QTFILE);
		if(emptystr(pp->user))
			kstrdup(&pp->user, eve);
		devdir(c, q, pp->name, l, pp->user, pp->perm, dp);
		qunlock(&unit->ctl);
		decref(&sdev->r);
		return 1;
	case Qraw:
	case Qctl:
	case Qpart:
		if((sdev = sdgetdev(DEV(c->qid))) == nil){
			devdir(c, q, "unavailable", 0, eve, 0, dp);
			return 1;
		}
		unit = sdev->unit[UNIT(c->qid)];
		qlock(&unit->ctl);
		r = sd2gen(c, TYPE(c->qid), dp);
		qunlock(&unit->ctl);
		decref(&sdev->r);
		return r;
	case Qtopctl:
		return sd1gen(c, TYPE(c->qid), dp);
	default:
		break;
	}

	return -1;
}