/*  * 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 <u.h>#include <libc.h>#include <thread.h>#include <fcall.h>#include "usb.h"#include "usbfs.h" typedef struct Rpc Rpc; enum{	Incr = 3,	/* increments for fs array */	Dtop = 0,	/* high 32 bits for / 	*/	Qdir = 0,	/* low 32 bits for /devdir */}; QLock fslck;static Usbfs** fs;static int nfs;static int fsused;static int exitonclose = 1; voidusbfsexits(int y){	exitonclose = y;} static intqiddev(uvlong path){	return (int)(path>>32) & 0xFF;} static intqidfile(uvlong path){	return (int)(path & 0xFFFFFFFFULL);} static uvlongmkqid(int qd, int qf){	return ((uvlong)qd << 32) | (uvlong)qf;} voidusbfsdirdump(void){	int i; 	qlock(&fslck);	fprint(2, "%s: fs list: (%d used %d total)\n", argv0, fsused, nfs);	for(i = 1; i < nfs; i++)		if(fs[i] != nil)			if(fs[i]->dev != nil)				fprint(2, "%s\t%s dev %#p refs %ld\n",					argv0, fs[i]->name, fs[i]->dev, fs[i]->dev->ref);			else				fprint(2, "%s:\t%s\n", argv0, fs[i]->name);	qunlock(&fslck);} voidusbfsadd(Usbfs *dfs){	int i, j; 	dprint(2, "%s: fsadd %s\n", argv0, dfs->name);	qlock(&fslck);	for(i = 1; i < nfs; i++)		if(fs[i] == nil)			break;	if(i >= nfs){		if((nfs%Incr) == 0){			fs = realloc(fs, sizeof(Usbfs*) * (nfs+Incr));			if(fs == nil)				sysfatal("realloc: %r");			for(j = nfs; j < nfs+Incr; j++)				fs[j] = nil;		}		if(nfs == 0)	/* do not use entry 0 */			nfs++;		fs[nfs++] = dfs;	}else		fs[i] = dfs;	dfs->qid = mkqid(i, 0);	fsused++;	qunlock(&fslck);} static voidusbfsdelnth(int i){	if(fs[i] != nil){		dprint(2, "%s: fsdel %s", argv0, fs[i]->name);		if(fs[i]->dev != nil){			dprint(2, " dev %#p ref %ld\n",				fs[i]->dev, fs[i]->dev->ref);		}else			dprint(2, "no dev\n");		if(fs[i]->end != nil)			fs[i]->end(fs[i]);		closedev(fs[i]->dev);		fsused--;	}	fs[i] = nil;	if(fsused == 0 && exitonclose != 0){		fprint(2, "%s: all file systems gone: exiting\n", argv0);		threadexitsall(nil);	}} voidusbfsdel(Usbfs *dfs){	int i; 	qlock(&fslck);	for(i = 0; i < nfs; i++)		if(dfs == nil || fs[i] == dfs){			usbfsdelnth(i);			if(dfs != nil)				break;		}	qunlock(&fslck);} static voidfsend(Usbfs*){	dprint(2, "%s: fsend\n", argv0);	usbfsdel(nil);} voidusbfsgone(char *dir){	int i; 	qlock(&fslck);	/* devices may have more than one fs */	for(i = 0; i < nfs; i++)		if(fs[i] != nil && fs[i]->dev != nil)		if(strcmp(fs[i]->dev->dir, dir) == 0)			usbfsdelnth(i);	qunlock(&fslck);} static voidfsclone(Usbfs*, Fid *o, Fid *n){	int qd;	Dev *dev;	void (*xfsclone)(Usbfs *fs, Fid *of, Fid *nf); 	xfsclone = nil;	dev = nil;	qd = qiddev(o->qid.path);	qlock(&fslck);	if(qd != Dtop && fs[qd] != nil && fs[qd]->clone != nil){		dev = fs[qd]->dev;		if(dev != nil)			incref(dev);		xfsclone = fs[qd]->clone;	}	qunlock(&fslck);	if(xfsclone != nil){		xfsclone(fs[qd], o, n);	}	if(dev != nil)		closedev(dev);} static intfswalk(Usbfs*, Fid *fid, char *name){	Qid q;	int qd, qf;	int i;	int rc;	Dev *dev;	Dir d;	int (*xfswalk)(Usbfs *fs, Fid *f, char *name); 	q = fid->qid;	qd = qiddev(q.path);	qf = qidfile(q.path); 	q.type = QTDIR;	q.vers = 0;	if(strcmp(name, "..") == 0)		if(qd == Dtop || qf == Qdir){			q.path = mkqid(Dtop, Qdir);			fid->qid = q;			return 0;		}	if(qd != 0){		qlock(&fslck);		if(fs[qd] == nil){			qunlock(&fslck);			werrstr(Eio);			return -1;		}		dev = fs[qd]->dev;		if(dev != nil)			incref(dev);		xfswalk = fs[qd]->walk;		qunlock(&fslck);		rc = xfswalk(fs[qd], fid, name);		if(dev != nil)			closedev(dev);		return rc;	}	qlock(&fslck);	for(i = 0; i < nfs; i++)		if(fs[i] != nil && strcmp(name, fs[i]->name) == 0){			q.path = mkqid(i, Qdir);			fs[i]->stat(fs[i], q, &d); /* may be a file */			fid->qid = d.qid;			qunlock(&fslck);			return 0;		}	qunlock(&fslck);	werrstr(Enotfound);	return -1;} static intfsopen(Usbfs*, Fid *fid, int mode){	int qd;	int rc;	Dev *dev;	int (*xfsopen)(Usbfs *fs, Fid *f, int mode); 	qd = qiddev(fid->qid.path);	if(qd == Dtop)		return 0;	qlock(&fslck);	if(fs[qd] == nil){		qunlock(&fslck);		werrstr(Eio);		return -1;	}	dev = fs[qd]->dev;	if(dev != nil)		incref(dev);	xfsopen = fs[qd]->open;	qunlock(&fslck);	if(xfsopen != nil)		rc = xfsopen(fs[qd], fid, mode);	else		rc = 0;	if(dev != nil)		closedev(dev);	return rc;} static intdirgen(Usbfs*, Qid, int n, Dir *d, void *){	int i;	Dev *dev;	char *nm; 	qlock(&fslck);	for(i = 0; i < nfs; i++)		if(fs[i] != nil && n-- == 0){			d->qid.type = QTDIR;			d->qid.path = mkqid(i, Qdir);			d->qid.vers = 0;			dev = fs[i]->dev;			if(dev != nil)				incref(dev);			nm = d->name;			fs[i]->stat(fs[i], d->qid, d);			d->name = nm;			strncpy(d->name, fs[i]->name, Namesz);			if(dev != nil)				closedev(dev);			qunlock(&fslck);			return 0;		}	qunlock(&fslck);	return -1;} static longfsread(Usbfs*, Fid *fid, void *data, long cnt, vlong off){	int qd;	int rc;	Dev *dev;	Qid q;	long (*xfsread)(Usbfs *fs, Fid *f, void *data, long count, vlong ); 	q = fid->qid;	qd = qiddev(q.path);	if(qd == Dtop)		return usbdirread(nil, q, data, cnt, off, dirgen, nil);	qlock(&fslck);	if(fs[qd] == nil){		qunlock(&fslck);		werrstr(Eio);		return -1;	}	dev = fs[qd]->dev;	if(dev != nil)		incref(dev);	xfsread = fs[qd]->read;	qunlock(&fslck);	rc = xfsread(fs[qd], fid, data, cnt, off);	if(dev != nil)		closedev(dev);	return rc;} static longfswrite(Usbfs*, Fid *fid, void *data, long cnt, vlong off){	int qd;	int rc;	Dev *dev;	long (*xfswrite)(Usbfs *fs, Fid *f, void *data, long count, vlong ); 	qd = qiddev(fid->qid.path);	if(qd == Dtop)		sysfatal("fswrite: not for usbd /");	qlock(&fslck);	if(fs[qd] == nil){		qunlock(&fslck);		werrstr(Eio);		return -1;	}	dev = fs[qd]->dev;	if(dev != nil)		incref(dev);	xfswrite = fs[qd]->write;	qunlock(&fslck);	rc = xfswrite(fs[qd], fid, data, cnt, off);	if(dev != nil)		closedev(dev);	return rc;}  static voidfsclunk(Usbfs*, Fid* fid){	int qd;	Dev *dev;	void (*xfsclunk)(Usbfs *fs, Fid *f); 	dev = nil;	qd = qiddev(fid->qid.path);	qlock(&fslck);	if(qd != Dtop && fs[qd] != nil){		dev=fs[qd]->dev;		if(dev != nil)			incref(dev);		xfsclunk = fs[qd]->clunk;	}else		xfsclunk = nil;	qunlock(&fslck);	if(xfsclunk != nil){		xfsclunk(fs[qd], fid);	}	if(dev != nil)		closedev(dev);} static intfsstat(Usbfs*, Qid qid, Dir *d){	int qd;	int rc;	Dev *dev;	int (*xfsstat)(Usbfs *fs, Qid q, Dir *d); 	qd = qiddev(qid.path);	if(qd == Dtop){		d->qid = qid;		d->name = "usb";		d->length = 0;		d->mode = 0555|DMDIR;		return 0;	}	qlock(&fslck);	if(fs[qd] == nil){		qunlock(&fslck);		werrstr(Eio);		return -1;	}	xfsstat = fs[qd]->stat;	dev = fs[qd]->dev;	if(dev != nil)		incref(dev);	qunlock(&fslck);	rc = xfsstat(fs[qd], qid, d);	if(dev != nil)		closedev(dev);	return rc;} Usbfs usbdirfs ={	.walk = fswalk,	.clone = fsclone,	.clunk = fsclunk,	.open = fsopen,	.read = fsread,	.write = fswrite,	.stat = fsstat,	.end = fsend,};